bc: new applet, throws warning
authorGavin Howard <yzena.tech@gmail.com>
Sat, 3 Nov 2018 17:00:21 +0000 (11:00 -0600)
committerDenys Vlasenko <vda.linux@googlemail.com>
Wed, 5 Dec 2018 14:40:38 +0000 (15:40 +0100)
Signed-off-by: Gavin Howard <yzena.tech@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
miscutils/bc.c [new file with mode: 0644]
miscutils/dc.c

diff --git a/miscutils/bc.c b/miscutils/bc.c
new file mode 100644 (file)
index 0000000..bf0cbc3
--- /dev/null
@@ -0,0 +1,7449 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
+ * Copyright (c) 2018 Gavin D. Howard and contributors.
+ *
+ * ** Automatically generated from https://github.com/gavinhoward/bc **
+ * **        Do not edit unless you know what you are doing.         **
+ */
+//config:config BC
+//config:      bool "bc (45 kb; 49 kb when combined with dc)"
+//config:      default y
+//config:      help
+//config:      bc is a command-line, arbitrary-precision calculator with a
+//config:      Turing-complete language. See the GNU bc manual
+//config:      (https://www.gnu.org/software/bc/manual/bc.html) and bc spec
+//config:      (http://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html)
+//config:      for details.
+//config:
+//config:      This bc has four differences to the GNU bc:
+//config:
+//config:        1) The period (.) can also be used as a shortcut for "last", as in
+//config:           the BSD bc.
+//config:        2) Arrays are copied before being passed as arguments to
+//config:           functions. This behavior is required by the bc spec.
+//config:        3) Arrays can be passed to the builtin "length" function to get
+//config:           the number of elements currently in the array. The following
+//config:           example prints "1":
+//config:
+//config:             a[0] = 0
+//config:             length(a[])
+//config:
+//config:        4) The precedence of the boolean "not" operator (!) is equal to
+//config:           that of the unary minus (-), or negation, operator. This still
+//config:           allows POSIX-compliant scripts to work while somewhat
+//config:           preserving expected behavior (versus C) and making parsing
+//config:           easier.
+//config:
+//config:      Options:
+//config:
+//config:        -i  --interactive  force interactive mode
+//config:        -l  --mathlib      use predefined math routines:
+//config:
+//config:                             s(expr)  =  sine of expr in radians
+//config:                             c(expr)  =  cosine of expr in radians
+//config:                             a(expr)  =  arctangent of expr, returning
+//config:                                         radians
+//config:                             l(expr)  =  natural log of expr
+//config:                             e(expr)  =  raises e to the power of expr
+//config:                             j(n, x)  =  Bessel function of integer order
+//config:                                         n of x
+//config:
+//config:        -q  --quiet        don't print version and copyright.
+//config:        -s  --standard     error if any non-POSIX extensions are used.
+//config:        -w  --warn         warn if any non-POSIX extensions are used.
+//config:        -v  --version      print version and copyright and exit.
+//config:
+//config:      Long options are only available if FEATURE_BC_LONG_OPTIONS is
+//config:      enabled.
+//config:
+//config:config DC
+//config:      bool "dc (38 kb; 49 kb when combined with bc)"
+//config:      default y
+//config:      help
+//config:      dc is a reverse-polish notation command-line calculator which
+//config:      supports unlimited precision arithmetic. See the FreeBSD man page
+//config:      (https://www.unix.com/man-page/FreeBSD/1/dc/) and GNU dc manual
+//config:      (https://www.gnu.org/software/bc/manual/dc-1.05/html_mono/dc.html)
+//config:      for details.
+//config:
+//config:      This dc has a few differences from the two above:
+//config:
+//config:        1) When printing a byte stream (command "P"), this bc follows what
+//config:           the FreeBSD dc does.
+//config:        2) This dc implements the GNU extensions for divmod ("~") and
+//config:           modular exponentiation ("|").
+//config:        3) This dc implements all FreeBSD extensions, except for "J" and
+//config:           "M".
+//config:        4) Like the FreeBSD dc, this dc supports extended registers.
+//config:           However, they are implemented differently. When it encounters
+//config:           whitespace where a register should be, it skips the whitespace.
+//config:           If the character following is not a lowercase letter, an error
+//config:           is issued. Otherwise, the register name is parsed by the
+//config:           following regex:
+//config:
+//config:             [a-z][a-z0-9_]*
+//config:
+//config:           This generally means that register names will be surrounded by
+//config:           whitespace.
+//config:
+//config:           Examples:
+//config:
+//config:             l idx s temp L index S temp2 < do_thing
+//config:
+//config:           Also note that, like the FreeBSD dc, extended registers are not
+//config:           allowed unless the "-x" option is given.
+//config:
+//config:config FEATURE_BC_SIGNALS
+//config:      bool "Enable bc/dc signal handling"
+//config:      default y
+//config:      depends on BC || DC
+//config:      help
+//config:      Enable signal handling for bc and dc.
+//config:
+//config:config FEATURE_BC_LONG_OPTIONS
+//config:      bool "Enable bc/dc long options"
+//config:      default y
+//config:      depends on BC || DC
+//config:      help
+//config:      Enable long options for bc and dc.
+
+//applet:IF_BC(APPLET(bc, BB_DIR_USR_BIN, BB_SUID_DROP))
+//applet:IF_DC(APPLET(dc, BB_DIR_USR_BIN, BB_SUID_DROP))
+
+//kbuild:lib-$(CONFIG_BC) += bc.o
+//kbuild:lib-$(CONFIG_DC) += bc.o
+
+//usage:#define bc_trivial_usage
+//usage:       "EXPRESSION...\n"
+//usage:       "function_definition\n"
+//usage:
+//usage:#define bc_full_usage "\n\n"
+//usage:       "See www.gnu.org/software/bc/manual/bc.html\n"
+//usage:
+//usage:#define bc_example_usage
+//usage:       "3 + 4.129\n"
+//usage:       "1903 - 2893\n"
+//usage:       "-129 * 213.28935\n"
+//usage:       "12 / -1932\n"
+//usage:       "12 % 12\n"
+//usage:       "34 ^ 189\n"
+//usage:       "scale = 13\n"
+//usage:       "ibase = 2\n"
+//usage:       "obase = A\n"
+//usage:
+//usage:#define dc_trivial_usage
+//usage:       "EXPRESSION..."
+//usage:
+//usage:#define dc_full_usage "\n\n"
+//usage:       "Tiny RPN calculator. Operations:\n"
+//usage:       "+, add, -, sub, *, mul, /, div, %, mod, ^, exp, ~, divmod, |, "
+//usage:       "modular exponentiation,\n"
+//usage:       "p - print top of the stack (without popping),\n"
+//usage:       "f - print entire stack,\n"
+//usage:       "k - pop the value and set the precision.\n"
+//usage:       "i - pop the value and set input radix.\n"
+//usage:       "o - pop the value and set output radix.\n"
+//usage:       "Examples: 'dc 2 2 add p' -> 4, 'dc 8 8 mul 2 2 + / p' -> 16"
+//usage:
+//usage:#define dc_example_usage
+//usage:       "$ dc 2 2 + p\n"
+//usage:       "4\n"
+//usage:       "$ dc 8 8 \\* 2 2 + / p\n"
+//usage:       "16\n"
+//usage:       "$ dc 0 1 and p\n"
+//usage:       "0\n"
+//usage:       "$ dc 0 1 or p\n"
+//usage:       "1\n"
+//usage:       "$ echo 72 9 div 8 mul p | dc\n"
+//usage:       "64\n"
+
+#include "libbb.h"
+
+typedef enum BcStatus {
+
+       BC_STATUS_SUCCESS,
+
+       BC_STATUS_ALLOC_ERR,
+       BC_STATUS_IO_ERR,
+       BC_STATUS_BIN_FILE,
+       BC_STATUS_PATH_IS_DIR,
+
+       BC_STATUS_LEX_BAD_CHAR,
+       BC_STATUS_LEX_NO_STRING_END,
+       BC_STATUS_LEX_NO_COMMENT_END,
+       BC_STATUS_LEX_EOF,
+#ifdef ENABLE_DC
+       BC_STATUS_LEX_EXTENDED_REG,
+#endif // ENABLE_DC
+
+       BC_STATUS_PARSE_BAD_TOKEN,
+       BC_STATUS_PARSE_BAD_EXP,
+       BC_STATUS_PARSE_EMPTY_EXP,
+       BC_STATUS_PARSE_BAD_PRINT,
+       BC_STATUS_PARSE_BAD_FUNC,
+       BC_STATUS_PARSE_BAD_ASSIGN,
+       BC_STATUS_PARSE_NO_AUTO,
+       BC_STATUS_PARSE_DUPLICATE_LOCAL,
+       BC_STATUS_PARSE_NO_BLOCK_END,
+
+       BC_STATUS_MATH_NEGATIVE,
+       BC_STATUS_MATH_NON_INTEGER,
+       BC_STATUS_MATH_OVERFLOW,
+       BC_STATUS_MATH_DIVIDE_BY_ZERO,
+       BC_STATUS_MATH_BAD_STRING,
+
+       BC_STATUS_EXEC_FILE_ERR,
+       BC_STATUS_EXEC_MISMATCHED_PARAMS,
+       BC_STATUS_EXEC_UNDEFINED_FUNC,
+       BC_STATUS_EXEC_FILE_NOT_EXECUTABLE,
+       BC_STATUS_EXEC_NUM_LEN,
+       BC_STATUS_EXEC_NAME_LEN,
+       BC_STATUS_EXEC_STRING_LEN,
+       BC_STATUS_EXEC_ARRAY_LEN,
+       BC_STATUS_EXEC_BAD_IBASE,
+       BC_STATUS_EXEC_BAD_SCALE,
+       BC_STATUS_EXEC_BAD_READ_EXPR,
+       BC_STATUS_EXEC_REC_READ,
+       BC_STATUS_EXEC_BAD_TYPE,
+       BC_STATUS_EXEC_BAD_OBASE,
+       BC_STATUS_EXEC_SIGNAL,
+       BC_STATUS_EXEC_STACK,
+
+       BC_STATUS_VEC_OUT_OF_BOUNDS,
+       BC_STATUS_VEC_ITEM_EXISTS,
+
+#ifdef ENABLE_BC
+       BC_STATUS_POSIX_NAME_LEN,
+       BC_STATUS_POSIX_COMMENT,
+       BC_STATUS_POSIX_BAD_KW,
+       BC_STATUS_POSIX_DOT,
+       BC_STATUS_POSIX_RET,
+       BC_STATUS_POSIX_BOOL,
+       BC_STATUS_POSIX_REL_POS,
+       BC_STATUS_POSIX_MULTIREL,
+       BC_STATUS_POSIX_FOR1,
+       BC_STATUS_POSIX_FOR2,
+       BC_STATUS_POSIX_FOR3,
+       BC_STATUS_POSIX_BRACE,
+#endif // ENABLE_BC
+
+       BC_STATUS_QUIT,
+       BC_STATUS_LIMITS,
+
+       BC_STATUS_INVALID_OPTION,
+
+} BcStatus;
+
+#define BC_ERR_IDX_VM (0)
+#define BC_ERR_IDX_LEX (1)
+#define BC_ERR_IDX_PARSE (2)
+#define BC_ERR_IDX_MATH (3)
+#define BC_ERR_IDX_EXEC (4)
+#define BC_ERR_IDX_VEC (5)
+#ifdef ENABLE_BC
+#define BC_ERR_IDX_POSIX (6)
+#endif // ENABLE_BC
+
+#define BC_VEC_INVALID_IDX ((size_t) -1)
+#define BC_VEC_START_CAP (1 << 5)
+
+typedef void (*BcVecFree)(void *);
+typedef int (*BcVecCmp)(const void *, const void *);
+
+typedef struct BcVec {
+       char *v;
+       size_t len;
+       size_t cap;
+       size_t size;
+       BcVecFree dtor;
+} BcVec;
+
+#define bc_vec_pop(v) (bc_vec_npop((v), 1))
+#define bc_vec_top(v) (bc_vec_item_rev((v), 0))
+
+#define bc_map_init(v) (bc_vec_init((v), sizeof(BcId), bc_id_free))
+
+#define BC_READ_BIN_CHAR(c) ((((c) < ' ' && !isspace((c))) || (c) > '~'))
+
+typedef signed char BcDig;
+
+typedef struct BcNum {
+       BcDig *restrict num;
+       size_t rdx;
+       size_t len;
+       size_t cap;
+       bool neg;
+} BcNum;
+
+#define BC_NUM_MIN_BASE ((unsigned long) 2)
+#define BC_NUM_MAX_IBASE ((unsigned long) 16)
+#define BC_NUM_DEF_SIZE (16)
+#define BC_NUM_PRINT_WIDTH (69)
+
+#define BC_NUM_KARATSUBA_LEN (32)
+
+#define BC_NUM_NEG(n, neg) ((((ssize_t)(n)) ^ -((ssize_t)(neg))) + (neg))
+#define BC_NUM_ONE(n) ((n)->len == 1 && (n)->rdx == 0 && (n)->num[0] == 1)
+#define BC_NUM_INT(n) ((n)->len - (n)->rdx)
+#define BC_NUM_AREQ(a, b) \
+       (BC_MAX((a)->rdx, (b)->rdx) + BC_MAX(BC_NUM_INT(a), BC_NUM_INT(b)) + 1)
+#define BC_NUM_MREQ(a, b, scale) \
+       (BC_NUM_INT(a) + BC_NUM_INT(b) + BC_MAX((scale), (a)->rdx + (b)->rdx) + 1)
+
+typedef BcStatus (*BcNumBinaryOp)(BcNum *, BcNum *, BcNum *, size_t);
+typedef void (*BcNumDigitOp)(size_t, size_t, bool, size_t *, size_t);
+
+static void bc_num_init(BcNum *n, size_t req);
+static void bc_num_expand(BcNum *n, size_t req);
+static void bc_num_copy(BcNum *d, BcNum *s);
+static void bc_num_free(void *num);
+
+static BcStatus bc_num_ulong(BcNum *n, unsigned long *result);
+static BcStatus bc_num_ulong2num(BcNum *n, unsigned long val);
+
+static BcStatus bc_num_add(BcNum *a, BcNum *b, BcNum *c, size_t scale);
+static BcStatus bc_num_sub(BcNum *a, BcNum *b, BcNum *c, size_t scale);
+static BcStatus bc_num_mul(BcNum *a, BcNum *b, BcNum *c, size_t scale);
+static BcStatus bc_num_div(BcNum *a, BcNum *b, BcNum *c, size_t scale);
+static BcStatus bc_num_mod(BcNum *a, BcNum *b, BcNum *c, size_t scale);
+static BcStatus bc_num_pow(BcNum *a, BcNum *b, BcNum *c, size_t scale);
+static BcStatus bc_num_sqrt(BcNum *a, BcNum *b, size_t scale);
+static BcStatus bc_num_divmod(BcNum *a, BcNum *b, BcNum *c, BcNum *d,
+                              size_t scale);
+
+typedef enum BcInst {
+
+#ifdef ENABLE_BC
+       BC_INST_INC_PRE,
+       BC_INST_DEC_PRE,
+       BC_INST_INC_POST,
+       BC_INST_DEC_POST,
+#endif // ENABLE_BC
+
+       BC_INST_NEG,
+
+       BC_INST_POWER,
+       BC_INST_MULTIPLY,
+       BC_INST_DIVIDE,
+       BC_INST_MODULUS,
+       BC_INST_PLUS,
+       BC_INST_MINUS,
+
+       BC_INST_REL_EQ,
+       BC_INST_REL_LE,
+       BC_INST_REL_GE,
+       BC_INST_REL_NE,
+       BC_INST_REL_LT,
+       BC_INST_REL_GT,
+
+       BC_INST_BOOL_NOT,
+       BC_INST_BOOL_OR,
+       BC_INST_BOOL_AND,
+
+#ifdef ENABLE_BC
+       BC_INST_ASSIGN_POWER,
+       BC_INST_ASSIGN_MULTIPLY,
+       BC_INST_ASSIGN_DIVIDE,
+       BC_INST_ASSIGN_MODULUS,
+       BC_INST_ASSIGN_PLUS,
+       BC_INST_ASSIGN_MINUS,
+#endif // ENABLE_BC
+       BC_INST_ASSIGN,
+
+       BC_INST_NUM,
+       BC_INST_VAR,
+       BC_INST_ARRAY_ELEM,
+       BC_INST_ARRAY,
+
+       BC_INST_SCALE_FUNC,
+       BC_INST_IBASE,
+       BC_INST_SCALE,
+       BC_INST_LAST,
+       BC_INST_LENGTH,
+       BC_INST_READ,
+       BC_INST_OBASE,
+       BC_INST_SQRT,
+
+       BC_INST_PRINT,
+       BC_INST_PRINT_POP,
+       BC_INST_STR,
+       BC_INST_PRINT_STR,
+
+#ifdef ENABLE_BC
+       BC_INST_JUMP,
+       BC_INST_JUMP_ZERO,
+
+       BC_INST_CALL,
+
+       BC_INST_RET,
+       BC_INST_RET0,
+
+       BC_INST_HALT,
+#endif // ENABLE_BC
+
+       BC_INST_POP,
+       BC_INST_POP_EXEC,
+
+#ifdef ENABLE_DC
+       BC_INST_MODEXP,
+       BC_INST_DIVMOD,
+
+       BC_INST_EXECUTE,
+       BC_INST_EXEC_COND,
+
+       BC_INST_ASCIIFY,
+       BC_INST_PRINT_STREAM,
+
+       BC_INST_PRINT_STACK,
+       BC_INST_CLEAR_STACK,
+       BC_INST_STACK_LEN,
+       BC_INST_DUPLICATE,
+       BC_INST_SWAP,
+
+       BC_INST_LOAD,
+       BC_INST_PUSH_VAR,
+       BC_INST_PUSH_TO_VAR,
+
+       BC_INST_QUIT,
+       BC_INST_NQUIT,
+
+       BC_INST_INVALID = -1,
+#endif // ENABLE_DC
+
+} BcInst;
+
+typedef struct BcId {
+       char *name;
+       size_t idx;
+} BcId;
+
+typedef struct BcFunc {
+       BcVec code;
+       BcVec labels;
+       size_t nparams;
+       BcVec autos;
+} BcFunc;
+
+typedef enum BcResultType {
+
+       BC_RESULT_TEMP,
+
+       BC_RESULT_VAR,
+       BC_RESULT_ARRAY_ELEM,
+       BC_RESULT_ARRAY,
+
+       BC_RESULT_STR,
+
+       BC_RESULT_IBASE,
+       BC_RESULT_SCALE,
+       BC_RESULT_LAST,
+
+       // These are between to calculate ibase, obase, and last from instructions.
+       BC_RESULT_CONSTANT,
+       BC_RESULT_ONE,
+
+       BC_RESULT_OBASE,
+
+} BcResultType;
+
+typedef union BcResultData {
+       BcNum n;
+       BcVec v;
+       BcId id;
+} BcResultData;
+
+typedef struct BcResult {
+       BcResultType t;
+       BcResultData d;
+} BcResult;
+
+typedef struct BcInstPtr {
+       size_t func;
+       size_t idx;
+       size_t len;
+} BcInstPtr;
+
+static void bc_array_expand(BcVec *a, size_t len);
+static int bc_id_cmp(const void *e1, const void *e2);
+
+// BC_LEX_NEG is not used in lexing; it is only for parsing.
+typedef enum BcLexType {
+
+       BC_LEX_EOF,
+       BC_LEX_INVALID,
+
+       BC_LEX_OP_INC,
+       BC_LEX_OP_DEC,
+
+       BC_LEX_NEG,
+
+       BC_LEX_OP_POWER,
+       BC_LEX_OP_MULTIPLY,
+       BC_LEX_OP_DIVIDE,
+       BC_LEX_OP_MODULUS,
+       BC_LEX_OP_PLUS,
+       BC_LEX_OP_MINUS,
+
+       BC_LEX_OP_REL_EQ,
+       BC_LEX_OP_REL_LE,
+       BC_LEX_OP_REL_GE,
+       BC_LEX_OP_REL_NE,
+       BC_LEX_OP_REL_LT,
+       BC_LEX_OP_REL_GT,
+
+       BC_LEX_OP_BOOL_NOT,
+       BC_LEX_OP_BOOL_OR,
+       BC_LEX_OP_BOOL_AND,
+
+       BC_LEX_OP_ASSIGN_POWER,
+       BC_LEX_OP_ASSIGN_MULTIPLY,
+       BC_LEX_OP_ASSIGN_DIVIDE,
+       BC_LEX_OP_ASSIGN_MODULUS,
+       BC_LEX_OP_ASSIGN_PLUS,
+       BC_LEX_OP_ASSIGN_MINUS,
+       BC_LEX_OP_ASSIGN,
+
+       BC_LEX_NLINE,
+       BC_LEX_WHITESPACE,
+
+       BC_LEX_LPAREN,
+       BC_LEX_RPAREN,
+
+       BC_LEX_LBRACKET,
+       BC_LEX_COMMA,
+       BC_LEX_RBRACKET,
+
+       BC_LEX_LBRACE,
+       BC_LEX_SCOLON,
+       BC_LEX_RBRACE,
+
+       BC_LEX_STR,
+       BC_LEX_NAME,
+       BC_LEX_NUMBER,
+
+       BC_LEX_KEY_AUTO,
+       BC_LEX_KEY_BREAK,
+       BC_LEX_KEY_CONTINUE,
+       BC_LEX_KEY_DEFINE,
+       BC_LEX_KEY_ELSE,
+       BC_LEX_KEY_FOR,
+       BC_LEX_KEY_HALT,
+       BC_LEX_KEY_IBASE,
+       BC_LEX_KEY_IF,
+       BC_LEX_KEY_LAST,
+       BC_LEX_KEY_LENGTH,
+       BC_LEX_KEY_LIMITS,
+       BC_LEX_KEY_OBASE,
+       BC_LEX_KEY_PRINT,
+       BC_LEX_KEY_QUIT,
+       BC_LEX_KEY_READ,
+       BC_LEX_KEY_RETURN,
+       BC_LEX_KEY_SCALE,
+       BC_LEX_KEY_SQRT,
+       BC_LEX_KEY_WHILE,
+
+#ifdef ENABLE_DC
+       BC_LEX_EQ_NO_REG,
+       BC_LEX_OP_MODEXP,
+       BC_LEX_OP_DIVMOD,
+
+       BC_LEX_COLON,
+       BC_LEX_ELSE,
+       BC_LEX_EXECUTE,
+       BC_LEX_PRINT_STACK,
+       BC_LEX_CLEAR_STACK,
+       BC_LEX_STACK_LEVEL,
+       BC_LEX_DUPLICATE,
+       BC_LEX_SWAP,
+       BC_LEX_POP,
+
+       BC_LEX_ASCIIFY,
+       BC_LEX_PRINT_STREAM,
+
+       BC_LEX_STORE_IBASE,
+       BC_LEX_STORE_SCALE,
+       BC_LEX_LOAD,
+       BC_LEX_LOAD_POP,
+       BC_LEX_STORE_PUSH,
+       BC_LEX_STORE_OBASE,
+       BC_LEX_PRINT_POP,
+       BC_LEX_NQUIT,
+       BC_LEX_SCALE_FACTOR,
+#endif // ENABLE_DC
+
+} BcLexType;
+
+struct BcLex;
+typedef BcStatus (*BcLexNext)(struct BcLex *);
+
+typedef struct BcLex {
+
+       const char *buf;
+       size_t i;
+       size_t line;
+       const char *f;
+       size_t len;
+       bool newline;
+
+       struct {
+               BcLexType t;
+               BcLexType last;
+               BcVec v;
+       } t;
+
+       BcLexNext next;
+
+} BcLex;
+
+#define BC_PARSE_STREND ((char) UCHAR_MAX)
+
+#define bc_parse_push(p, i) (bc_vec_pushByte(&(p)->func->code, (char) (i)))
+#define bc_parse_updateFunc(p, f) \
+       ((p)->func = bc_vec_item(&(p)->prog->fns, ((p)->fidx = (f))))
+
+#define BC_PARSE_REL (1 << 0)
+#define BC_PARSE_PRINT (1 << 1)
+#define BC_PARSE_NOCALL (1 << 2)
+#define BC_PARSE_NOREAD (1 << 3)
+#define BC_PARSE_ARRAY (1 << 4)
+
+#define BC_PARSE_TOP_FLAG_PTR(parse) ((uint8_t *) bc_vec_top(&(parse)->flags))
+#define BC_PARSE_TOP_FLAG(parse) (*(BC_PARSE_TOP_FLAG_PTR(parse)))
+
+#define BC_PARSE_FLAG_FUNC_INNER (1 << 0)
+#define BC_PARSE_FUNC_INNER(parse) \
+       (BC_PARSE_TOP_FLAG(parse) & BC_PARSE_FLAG_FUNC_INNER)
+
+#define BC_PARSE_FLAG_FUNC (1 << 1)
+#define BC_PARSE_FUNC(parse) (BC_PARSE_TOP_FLAG(parse) & BC_PARSE_FLAG_FUNC)
+
+#define BC_PARSE_FLAG_BODY (1 << 2)
+#define BC_PARSE_BODY(parse) (BC_PARSE_TOP_FLAG(parse) & BC_PARSE_FLAG_BODY)
+
+#define BC_PARSE_FLAG_LOOP (1 << 3)
+#define BC_PARSE_LOOP(parse) (BC_PARSE_TOP_FLAG(parse) & BC_PARSE_FLAG_LOOP)
+
+#define BC_PARSE_FLAG_LOOP_INNER (1 << 4)
+#define BC_PARSE_LOOP_INNER(parse) \
+       (BC_PARSE_TOP_FLAG(parse) & BC_PARSE_FLAG_LOOP_INNER)
+
+#define BC_PARSE_FLAG_IF (1 << 5)
+#define BC_PARSE_IF(parse) (BC_PARSE_TOP_FLAG(parse) & BC_PARSE_FLAG_IF)
+
+#define BC_PARSE_FLAG_ELSE (1 << 6)
+#define BC_PARSE_ELSE(parse) (BC_PARSE_TOP_FLAG(parse) & BC_PARSE_FLAG_ELSE)
+
+#define BC_PARSE_FLAG_IF_END (1 << 7)
+#define BC_PARSE_IF_END(parse) (BC_PARSE_TOP_FLAG(parse) & BC_PARSE_FLAG_IF_END)
+
+#define BC_PARSE_CAN_EXEC(parse)                                             \
+       (!(BC_PARSE_TOP_FLAG(parse) &                                            \
+          (BC_PARSE_FLAG_FUNC_INNER | BC_PARSE_FLAG_FUNC | BC_PARSE_FLAG_BODY | \
+           BC_PARSE_FLAG_LOOP | BC_PARSE_FLAG_LOOP_INNER | BC_PARSE_FLAG_IF |   \
+           BC_PARSE_FLAG_ELSE | BC_PARSE_FLAG_IF_END)))
+
+typedef struct BcOp {
+       char prec;
+       bool left;
+} BcOp;
+
+typedef struct BcParseNext {
+       uint32_t len;
+       BcLexType tokens[4];
+} BcParseNext;
+
+#define BC_PARSE_NEXT_TOKENS(...) .tokens = { __VA_ARGS__ }
+#define BC_PARSE_NEXT(a, ...)                         \
+       {                                                 \
+               .len = (a), BC_PARSE_NEXT_TOKENS(__VA_ARGS__) \
+       }
+
+struct BcParse;
+
+struct BcProgram;
+
+typedef void (*BcParseInit)(struct BcParse *, struct BcProgram *, size_t);
+typedef BcStatus (*BcParseParse)(struct BcParse *);
+typedef BcStatus (*BcParseExpr)(struct BcParse *, uint8_t);
+
+typedef struct BcParse {
+
+       BcParseParse parse;
+
+       BcLex l;
+
+       BcVec flags;
+
+       BcVec exits;
+       BcVec conds;
+
+       BcVec ops;
+
+       struct BcProgram *prog;
+       BcFunc *func;
+       size_t fidx;
+
+       size_t nbraces;
+       bool auto_part;
+
+} BcParse;
+
+#ifdef ENABLE_BC
+
+BcStatus bc_main(int argc, char *argv[]);
+
+typedef struct BcLexKeyword {
+       const char name[9];
+       const char len;
+       const bool posix;
+} BcLexKeyword;
+
+#define BC_LEX_KW_ENTRY(a, b, c)            \
+       {                                       \
+               .name = a, .len = (b), .posix = (c) \
+       }
+
+static BcStatus bc_lex_token(BcLex *l);
+
+#define BC_PARSE_TOP_OP(p) (*((BcLexType *) bc_vec_top(&(p)->ops)))
+#define BC_PARSE_LEAF(p, rparen)                                \
+       (((p) >= BC_INST_NUM && (p) <= BC_INST_SQRT) || (rparen) || \
+        (p) == BC_INST_INC_POST || (p) == BC_INST_DEC_POST)
+
+// We can calculate the conversion between tokens and exprs by subtracting the
+// position of the first operator in the lex enum and adding the position of the
+// first in the expr enum. Note: This only works for binary operators.
+#define BC_PARSE_TOKEN_INST(t) ((char) ((t) -BC_LEX_NEG + BC_INST_NEG))
+
+static BcStatus bc_parse_parse(BcParse *p);
+static BcStatus bc_parse_expr(BcParse *p, uint8_t flags, BcParseNext next);
+
+#endif // ENABLE_BC
+
+#ifdef ENABLE_DC
+
+#define DC_PARSE_BUF_LEN ((int) (sizeof(uint32_t) * CHAR_BIT))
+
+BcStatus dc_main(int argc, char *argv[]);
+
+static BcStatus dc_lex_token(BcLex *l);
+
+static void dc_parse_init(BcParse *p, struct BcProgram *prog, size_t func);
+static BcStatus dc_parse_expr(BcParse *p, uint8_t flags);
+
+#endif // ENABLE_DC
+
+typedef struct BcProgram {
+
+       size_t len;
+       size_t scale;
+
+       BcNum ib;
+       size_t ib_t;
+       BcNum ob;
+       size_t ob_t;
+
+       BcNum hexb;
+
+#ifdef ENABLE_DC
+       BcNum strmb;
+#endif // ENABLE_DC
+
+       BcVec results;
+       BcVec stack;
+
+       BcVec fns;
+       BcVec fn_map;
+
+       BcVec vars;
+       BcVec var_map;
+
+       BcVec arrs;
+       BcVec arr_map;
+
+       BcVec strs;
+       BcVec consts;
+
+       const char *file;
+
+       BcNum last;
+       BcNum zero;
+       BcNum one;
+
+       size_t nchars;
+
+       BcParseInit parse_init;
+       BcParseExpr parse_expr;
+
+} BcProgram;
+
+#define BC_PROG_STACK(s, n) ((s)->len >= ((size_t) n))
+
+#define BC_PROG_MAIN (0)
+#define BC_PROG_READ (1)
+
+#ifdef ENABLE_DC
+#define BC_PROG_REQ_FUNCS (2)
+#endif // ENABLE_DC
+
+#define BC_PROG_STR(n) (!(n)->num && !(n)->cap)
+#define BC_PROG_NUM(r, n) \
+       ((r)->t != BC_RESULT_ARRAY && (r)->t != BC_RESULT_STR && !BC_PROG_STR(n))
+
+typedef unsigned long (*BcProgramBuiltIn)(BcNum *);
+
+static void bc_program_addFunc(BcProgram *p, char *name, size_t *idx);
+static BcStatus bc_program_reset(BcProgram *p, BcStatus s);
+static BcStatus bc_program_exec(BcProgram *p);
+
+#define BC_FLAG_X (1 << 0)
+#define BC_FLAG_W (1 << 1)
+#define BC_FLAG_V (1 << 2)
+#define BC_FLAG_S (1 << 3)
+#define BC_FLAG_Q (1 << 4)
+#define BC_FLAG_L (1 << 5)
+#define BC_FLAG_I (1 << 6)
+
+#define BC_MAX(a, b) ((a) > (b) ? (a) : (b))
+#define BC_MIN(a, b) ((a) < (b) ? (a) : (b))
+
+#define BC_MAX_OBASE ((unsigned long) 999)
+#define BC_MAX_DIM ((unsigned long) INT_MAX)
+#define BC_MAX_SCALE ((unsigned long) UINT_MAX)
+#define BC_MAX_STRING ((unsigned long) UINT_MAX - 1)
+#define BC_MAX_NAME BC_MAX_STRING
+#define BC_MAX_NUM BC_MAX_STRING
+#define BC_MAX_EXP ((unsigned long) LONG_MAX)
+#define BC_MAX_VARS ((unsigned long) SIZE_MAX - 1)
+
+typedef struct BcVmExe {
+       BcParseInit init;
+       BcParseExpr exp;
+       char sbgn;
+       char send;
+} BcVmExe;
+
+typedef struct BcVm {
+
+       BcParse prs;
+       BcProgram prog;
+
+       uint32_t flags;
+       BcVec files;
+
+       char *env_args;
+       BcVmExe exe;
+
+} BcVm;
+
+typedef struct BcGlobals {
+
+       unsigned long sig;
+       unsigned long sigc;
+       unsigned long signe;
+
+       long tty;
+       long ttyin;
+       long posix;
+       long warn;
+       long exreg;
+
+       const char *name;
+#if ENABLE_FEATURE_BC_SIGNALS
+       const char *sig_msg;
+#endif // ENABLE_FEATURE_BC_SIGNALS
+       const char *help;
+       bool bc;
+
+} BcGlobals;
+
+#ifdef ENABLE_BC
+static BcStatus bc_vm_posixError(BcStatus s, const char *file, size_t line,
+                                 const char *msg);
+#endif // ENABLE_BC
+
+static void bc_vm_exit(BcStatus s);
+static void bc_vm_printf(FILE *restrict f, const char *fmt, ...);
+static void bc_vm_puts(const char *str, FILE *restrict f);
+static void bc_vm_putchar(int c);
+static void bc_vm_fflush(FILE *restrict f);
+
+static void bc_vm_info(const char *const help);
+static BcStatus bc_vm_run(int argc, char *argv[], BcVmExe exe,
+                          const char *env_len);
+
+static BcGlobals bcg;
+
+#ifdef ENABLE_BC
+static const char bc_name[] = "bc";
+#if ENABLE_FEATURE_BC_SIGNALS
+static const char bc_sig_msg[] = "\ninterrupt (type \"quit\" to exit)\n";
+#endif // ENABLE_FEATURE_BC_SIGNALS
+#endif // ENABLE_BC
+
+#ifdef ENABLE_DC
+static const char dc_name[] = "dc";
+#if ENABLE_FEATURE_BC_SIGNALS
+static const char dc_sig_msg[] = "\ninterrupt (type \"q\" to exit)\n";
+#endif // ENABLE_FEATURE_BC_SIGNALS
+#endif // ENABLE_DC
+
+static const char bc_copyright[] =
+       "Copyright (c) 2018 Gavin D. Howard and contributors\n"
+       "Report bugs at: https://github.com/gavinhoward/bc\n\n"
+       "This is free software with ABSOLUTELY NO WARRANTY.\n";
+
+static const char* const bc_args_env_name = "BC_ENV_ARGS";
+
+static const char bc_err_fmt[] = "\n%s error: %s\n";
+static const char bc_warn_fmt[] = "\n%s warning: %s\n";
+static const char bc_err_line[] = ":%zu\n\n";
+
+static const char *bc_errs[] = {
+       "VM",
+       "Lex",
+       "Parse",
+       "Math",
+       "Runtime",
+       "Vector",
+#ifdef ENABLE_BC
+       "POSIX",
+#endif // ENABLE_BC
+};
+
+static const uint8_t bc_err_ids[] = {
+       BC_ERR_IDX_VM, BC_ERR_IDX_VM, BC_ERR_IDX_VM, BC_ERR_IDX_VM, BC_ERR_IDX_VM,
+       BC_ERR_IDX_LEX, BC_ERR_IDX_LEX, BC_ERR_IDX_LEX, BC_ERR_IDX_LEX,
+#ifdef ENABLE_DC
+       BC_ERR_IDX_LEX,
+#endif // ENABLE_DC
+       BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE,
+       BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE,
+       BC_ERR_IDX_MATH, BC_ERR_IDX_MATH, BC_ERR_IDX_MATH, BC_ERR_IDX_MATH,
+       BC_ERR_IDX_MATH,
+#ifdef ENABLE_DC
+       BC_ERR_IDX_MATH,
+#endif // ENABLE_DC
+       BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC,
+       BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC,
+       BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC,
+       BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC,
+       BC_ERR_IDX_EXEC,
+       BC_ERR_IDX_VEC, BC_ERR_IDX_VEC,
+#ifdef ENABLE_BC
+       BC_ERR_IDX_POSIX, BC_ERR_IDX_POSIX, BC_ERR_IDX_POSIX, BC_ERR_IDX_POSIX,
+       BC_ERR_IDX_POSIX, BC_ERR_IDX_POSIX, BC_ERR_IDX_POSIX, BC_ERR_IDX_POSIX,
+       BC_ERR_IDX_POSIX, BC_ERR_IDX_POSIX, BC_ERR_IDX_POSIX, BC_ERR_IDX_POSIX,
+#endif // ENABLE_BC
+       BC_ERR_IDX_VM, BC_ERR_IDX_VM, BC_ERR_IDX_VM,
+};
+
+static const char *bc_err_msgs[] = {
+
+       NULL,
+       "memory allocation error",
+       "I/O error",
+       "file is not text:",
+       "path is a directory:",
+
+       "bad character",
+       "string end could not be found",
+       "comment end could not be found",
+       "end of file",
+#ifdef ENABLE_DC
+       "extended register",
+#endif // ENABLE_DC
+
+       "bad token",
+       "bad expression",
+       "empty expression",
+       "bad print statement",
+       "bad function definition",
+       "bad assignment: left side must be scale, ibase, "
+               "obase, last, var, or array element",
+       "no auto variable found",
+       "function parameter or auto var has the same name as another",
+       "block end could not be found",
+
+       "negative number",
+       "non integer number",
+       "overflow",
+       "divide by zero",
+       "bad number string",
+
+       "could not open file:",
+       "mismatched parameters",
+       "undefined function",
+       "file is not executable:",
+       "number too long: must be [1, BC_NUM_MAX]",
+       "name too long: must be [1, BC_NAME_MAX]",
+       "string too long: must be [1, BC_STRING_MAX]",
+       "array too long; must be [1, BC_DIM_MAX]",
+       "bad ibase; must be [2, 16]",
+       "bad scale; must be [0, BC_SCALE_MAX]",
+       "bad read() expression",
+       "read() call inside of a read() call",
+       "variable is wrong type",
+       "bad obase; must be [2, BC_BASE_MAX]",
+       "signal caught and not handled",
+       "stack has too few elements",
+
+       "index is out of bounds",
+       "item already exists",
+
+#ifdef ENABLE_BC
+       "POSIX only allows one character names; the following is bad:",
+       "POSIX does not allow '#' script comments",
+       "POSIX does not allow the following keyword:",
+       "POSIX does not allow a period ('.') as a shortcut for the last result",
+       "POSIX requires parentheses around return expressions",
+       "POSIX does not allow boolean operators; the following is bad:",
+       "POSIX does not allow comparison operators outside if or loops",
+       "POSIX requires exactly one comparison operator per condition",
+       "POSIX does not allow an empty init expression in a for loop",
+       "POSIX does not allow an empty condition expression in a for loop",
+       "POSIX does not allow an empty update expression in a for loop",
+       "POSIX requires the left brace be on the same line as the function header",
+#endif // ENABLE_BC
+
+};
+
+static const char bc_func_main[] = "(main)";
+static const char bc_func_read[] = "(read)";
+
+#ifdef ENABLE_BC
+static const BcLexKeyword bc_lex_kws[20] = {
+       BC_LEX_KW_ENTRY("auto", 4, true),
+       BC_LEX_KW_ENTRY("break", 5, true),
+       BC_LEX_KW_ENTRY("continue", 8, false),
+       BC_LEX_KW_ENTRY("define", 6, true),
+       BC_LEX_KW_ENTRY("else", 4, false),
+       BC_LEX_KW_ENTRY("for", 3, true),
+       BC_LEX_KW_ENTRY("halt", 4, false),
+       BC_LEX_KW_ENTRY("ibase", 5, true),
+       BC_LEX_KW_ENTRY("if", 2, true),
+       BC_LEX_KW_ENTRY("last", 4, false),
+       BC_LEX_KW_ENTRY("length", 6, true),
+       BC_LEX_KW_ENTRY("limits", 6, false),
+       BC_LEX_KW_ENTRY("obase", 5, true),
+       BC_LEX_KW_ENTRY("print", 5, false),
+       BC_LEX_KW_ENTRY("quit", 4, true),
+       BC_LEX_KW_ENTRY("read", 4, false),
+       BC_LEX_KW_ENTRY("return", 6, true),
+       BC_LEX_KW_ENTRY("scale", 5, true),
+       BC_LEX_KW_ENTRY("sqrt", 4, true),
+       BC_LEX_KW_ENTRY("while", 5, true),
+};
+
+// This is an array that corresponds to token types. An entry is
+// true if the token is valid in an expression, false otherwise.
+static const bool bc_parse_exprs[] = {
+       false, false, true, true, true, true, true, true, true, true, true, true,
+       true, true, true, true, true, true, true, true, true, true, true, true,
+       true, true, true, false, false, true, true, false, false, false, false,
+       false, false, false, true, true, false, false, false, false, false, false,
+       false, true, false, true, true, true, true, false, false, true, false, true,
+       true, false,
+};
+
+// This is an array of data for operators that correspond to token types.
+static const BcOp bc_parse_ops[] = {
+       { 0, false }, { 0, false },
+       { 1, false },
+       { 2, false },
+       { 3, true }, { 3, true }, { 3, true },
+       { 4, true }, { 4, true },
+       { 6, true }, { 6, true }, { 6, true }, { 6, true }, { 6, true }, { 6, true },
+       { 1, false },
+       { 7, true }, { 7, true },
+       { 5, false }, { 5, false }, { 5, false }, { 5, false }, { 5, false },
+       { 5, false }, { 5, false },
+};
+
+// These identify what tokens can come after expressions in certain cases.
+static const BcParseNext bc_parse_next_expr =
+       BC_PARSE_NEXT(4, BC_LEX_NLINE, BC_LEX_SCOLON, BC_LEX_RBRACE, BC_LEX_EOF);
+static const BcParseNext bc_parse_next_param =
+       BC_PARSE_NEXT(2, BC_LEX_RPAREN, BC_LEX_COMMA);
+static const BcParseNext bc_parse_next_print =
+       BC_PARSE_NEXT(4, BC_LEX_COMMA, BC_LEX_NLINE, BC_LEX_SCOLON, BC_LEX_EOF);
+static const BcParseNext bc_parse_next_rel = BC_PARSE_NEXT(1, BC_LEX_RPAREN);
+static const BcParseNext bc_parse_next_elem = BC_PARSE_NEXT(1, BC_LEX_RBRACKET);
+static const BcParseNext bc_parse_next_for = BC_PARSE_NEXT(1, BC_LEX_SCOLON);
+static const BcParseNext bc_parse_next_read =
+       BC_PARSE_NEXT(2, BC_LEX_NLINE, BC_LEX_EOF);
+#endif // ENABLE_BC
+
+#ifdef ENABLE_DC
+static const BcLexType dc_lex_regs[] = {
+       BC_LEX_OP_REL_EQ, BC_LEX_OP_REL_LE, BC_LEX_OP_REL_GE, BC_LEX_OP_REL_NE,
+       BC_LEX_OP_REL_LT, BC_LEX_OP_REL_GT, BC_LEX_SCOLON, BC_LEX_COLON,
+       BC_LEX_ELSE, BC_LEX_LOAD, BC_LEX_LOAD_POP, BC_LEX_OP_ASSIGN,
+       BC_LEX_STORE_PUSH,
+};
+
+static const size_t dc_lex_regs_len = sizeof(dc_lex_regs) / sizeof(BcLexType);
+
+static const BcLexType dc_lex_tokens[] = {
+       BC_LEX_OP_MODULUS, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_LPAREN,
+       BC_LEX_INVALID, BC_LEX_OP_MULTIPLY, BC_LEX_OP_PLUS, BC_LEX_INVALID,
+       BC_LEX_OP_MINUS, BC_LEX_INVALID, BC_LEX_OP_DIVIDE,
+       BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID,
+       BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID,
+       BC_LEX_INVALID, BC_LEX_INVALID,
+       BC_LEX_COLON, BC_LEX_SCOLON, BC_LEX_OP_REL_GT, BC_LEX_OP_REL_EQ,
+       BC_LEX_OP_REL_LT, BC_LEX_KEY_READ, BC_LEX_INVALID,
+       BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID,
+       BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_EQ_NO_REG, BC_LEX_INVALID,
+       BC_LEX_KEY_IBASE, BC_LEX_INVALID, BC_LEX_KEY_SCALE, BC_LEX_LOAD_POP,
+       BC_LEX_INVALID, BC_LEX_OP_BOOL_NOT, BC_LEX_KEY_OBASE, BC_LEX_PRINT_STREAM,
+       BC_LEX_NQUIT, BC_LEX_POP, BC_LEX_STORE_PUSH, BC_LEX_INVALID, BC_LEX_INVALID,
+       BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_SCALE_FACTOR, BC_LEX_INVALID,
+       BC_LEX_KEY_LENGTH, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID,
+       BC_LEX_OP_POWER, BC_LEX_NEG, BC_LEX_INVALID,
+       BC_LEX_ASCIIFY, BC_LEX_INVALID, BC_LEX_CLEAR_STACK, BC_LEX_DUPLICATE,
+       BC_LEX_ELSE, BC_LEX_PRINT_STACK, BC_LEX_INVALID, BC_LEX_INVALID,
+       BC_LEX_STORE_IBASE, BC_LEX_INVALID, BC_LEX_STORE_SCALE, BC_LEX_LOAD,
+       BC_LEX_INVALID, BC_LEX_PRINT_POP, BC_LEX_STORE_OBASE, BC_LEX_KEY_PRINT,
+       BC_LEX_KEY_QUIT, BC_LEX_SWAP, BC_LEX_OP_ASSIGN, BC_LEX_INVALID,
+       BC_LEX_INVALID, BC_LEX_KEY_SQRT, BC_LEX_INVALID, BC_LEX_EXECUTE,
+       BC_LEX_INVALID, BC_LEX_STACK_LEVEL,
+       BC_LEX_LBRACE, BC_LEX_OP_MODEXP, BC_LEX_INVALID, BC_LEX_OP_DIVMOD,
+       BC_LEX_INVALID
+};
+
+static const BcInst dc_parse_insts[] = {
+       BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_REL_GE,
+       BC_INST_INVALID, BC_INST_POWER, BC_INST_MULTIPLY, BC_INST_DIVIDE,
+       BC_INST_MODULUS, BC_INST_PLUS, BC_INST_MINUS,
+       BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID,
+       BC_INST_INVALID, BC_INST_INVALID,
+       BC_INST_BOOL_NOT, BC_INST_INVALID, BC_INST_INVALID,
+       BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID,
+       BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID,
+       BC_INST_INVALID, BC_INST_INVALID, BC_INST_REL_GT, BC_INST_INVALID,
+       BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_REL_GE,
+       BC_INST_INVALID, BC_INST_INVALID,
+       BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID,
+       BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID,
+       BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_IBASE,
+       BC_INST_INVALID, BC_INST_INVALID, BC_INST_LENGTH, BC_INST_INVALID,
+       BC_INST_OBASE, BC_INST_PRINT, BC_INST_QUIT, BC_INST_INVALID,
+       BC_INST_INVALID, BC_INST_SCALE, BC_INST_SQRT, BC_INST_INVALID,
+       BC_INST_REL_EQ, BC_INST_MODEXP, BC_INST_DIVMOD, BC_INST_INVALID,
+       BC_INST_INVALID, BC_INST_EXECUTE, BC_INST_PRINT_STACK, BC_INST_CLEAR_STACK,
+       BC_INST_STACK_LEN, BC_INST_DUPLICATE, BC_INST_SWAP, BC_INST_POP,
+       BC_INST_ASCIIFY, BC_INST_PRINT_STREAM, BC_INST_INVALID, BC_INST_INVALID,
+       BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID,
+       BC_INST_PRINT, BC_INST_NQUIT, BC_INST_SCALE_FUNC,
+};
+#endif // ENABLE_DC
+
+static const char bc_num_hex_digits[] = "0123456789ABCDEF";
+
+static const BcNumBinaryOp bc_program_ops[] = {
+       bc_num_pow, bc_num_mul, bc_num_div, bc_num_mod, bc_num_add, bc_num_sub,
+};
+
+static const char bc_program_stdin_name[] = "<stdin>";
+static const char bc_program_ready_msg[] = "ready for more input\n";
+
+#ifdef ENABLE_BC
+static const char *bc_lib_name = "gen/lib.bc";
+
+static const char bc_lib[] = {
+  115,99,97,108,101,61,50,48,10,100,101,102,105,110,101,32,101,40,120,41,123,
+  10,9,97,117,116,111,32,98,44,115,44,110,44,114,44,100,44,105,44,112,44,102,
+  44,118,10,9,98,61,105,98,97,115,101,10,9,105,98,97,115,101,61,65,10,9,105,102,
+  40,120,60,48,41,123,10,9,9,110,61,49,10,9,9,120,61,45,120,10,9,125,10,9,115,
+  61,115,99,97,108,101,10,9,114,61,54,43,115,43,48,46,52,52,42,120,10,9,115,99,
+  97,108,101,61,115,99,97,108,101,40,120,41,43,49,10,9,119,104,105,108,101,40,
+  120,62,49,41,123,10,9,9,100,43,61,49,10,9,9,120,47,61,50,10,9,9,115,99,97,108,
+  101,43,61,49,10,9,125,10,9,115,99,97,108,101,61,114,10,9,114,61,120,43,49,10,
+  9,112,61,120,10,9,102,61,118,61,49,10,9,102,111,114,40,105,61,50,59,118,33,
+  61,48,59,43,43,105,41,123,10,9,9,112,42,61,120,10,9,9,102,42,61,105,10,9,9,
+  118,61,112,47,102,10,9,9,114,43,61,118,10,9,125,10,9,119,104,105,108,101,40,
+  40,100,45,45,41,33,61,48,41,114,42,61,114,10,9,115,99,97,108,101,61,115,10,
+  9,105,98,97,115,101,61,98,10,9,105,102,40,110,33,61,48,41,114,101,116,117,114,
+  110,40,49,47,114,41,10,9,114,101,116,117,114,110,40,114,47,49,41,10,125,10,
+  100,101,102,105,110,101,32,108,40,120,41,123,10,9,97,117,116,111,32,98,44,115,
+  44,114,44,112,44,97,44,113,44,105,44,118,10,9,98,61,105,98,97,115,101,10,9,
+  105,98,97,115,101,61,65,10,9,105,102,40,120,60,61,48,41,123,10,9,9,114,61,40,
+  49,45,49,48,94,115,99,97,108,101,41,47,49,10,9,9,105,98,97,115,101,61,98,10,
+  9,9,114,101,116,117,114,110,40,114,41,10,9,125,10,9,115,61,115,99,97,108,101,
+  10,9,115,99,97,108,101,43,61,54,10,9,112,61,50,10,9,119,104,105,108,101,40,
+  120,62,61,50,41,123,10,9,9,112,42,61,50,10,9,9,120,61,115,113,114,116,40,120,
+  41,10,9,125,10,9,119,104,105,108,101,40,120,60,61,48,46,53,41,123,10,9,9,112,
+  42,61,50,10,9,9,120,61,115,113,114,116,40,120,41,10,9,125,10,9,114,61,97,61,
+  40,120,45,49,41,47,40,120,43,49,41,10,9,113,61,97,42,97,10,9,118,61,49,10,9,
+  102,111,114,40,105,61,51,59,118,33,61,48,59,105,43,61,50,41,123,10,9,9,97,42,
+  61,113,10,9,9,118,61,97,47,105,10,9,9,114,43,61,118,10,9,125,10,9,114,42,61,
+  112,10,9,115,99,97,108,101,61,115,10,9,105,98,97,115,101,61,98,10,9,114,101,
+  116,117,114,110,40,114,47,49,41,10,125,10,100,101,102,105,110,101,32,115,40,
+  120,41,123,10,9,97,117,116,111,32,98,44,115,44,114,44,110,44,97,44,113,44,105,
+  10,9,98,61,105,98,97,115,101,10,9,105,98,97,115,101,61,65,10,9,115,61,115,99,
+  97,108,101,10,9,115,99,97,108,101,61,49,46,49,42,115,43,50,10,9,97,61,97,40,
+  49,41,10,9,105,102,40,120,60,48,41,123,10,9,9,110,61,49,10,9,9,120,61,45,120,
+  10,9,125,10,9,115,99,97,108,101,61,48,10,9,113,61,40,120,47,97,43,50,41,47,
+  52,10,9,120,61,120,45,52,42,113,42,97,10,9,105,102,40,113,37,50,33,61,48,41,
+  120,61,45,120,10,9,115,99,97,108,101,61,115,43,50,10,9,114,61,97,61,120,10,
+  9,113,61,45,120,42,120,10,9,102,111,114,40,105,61,51,59,97,33,61,48,59,105,
+  43,61,50,41,123,10,9,9,97,42,61,113,47,40,105,42,40,105,45,49,41,41,10,9,9,
+  114,43,61,97,10,9,125,10,9,115,99,97,108,101,61,115,10,9,105,98,97,115,101,
+  61,98,10,9,105,102,40,110,33,61,48,41,114,101,116,117,114,110,40,45,114,47,
+  49,41,10,9,114,101,116,117,114,110,40,114,47,49,41,10,125,10,100,101,102,105,
+  110,101,32,99,40,120,41,123,10,9,97,117,116,111,32,98,44,115,10,9,98,61,105,
+  98,97,115,101,10,9,105,98,97,115,101,61,65,10,9,115,61,115,99,97,108,101,10,
+  9,115,99,97,108,101,42,61,49,46,50,10,9,120,61,115,40,50,42,97,40,49,41,43,
+  120,41,10,9,115,99,97,108,101,61,115,10,9,105,98,97,115,101,61,98,10,9,114,
+  101,116,117,114,110,40,120,47,49,41,10,125,10,100,101,102,105,110,101,32,97,
+  40,120,41,123,10,9,97,117,116,111,32,98,44,115,44,114,44,110,44,97,44,109,44,
+  116,44,102,44,105,44,117,10,9,98,61,105,98,97,115,101,10,9,105,98,97,115,101,
+  61,65,10,9,110,61,49,10,9,105,102,40,120,60,48,41,123,10,9,9,110,61,45,49,10,
+  9,9,120,61,45,120,10,9,125,10,9,105,102,40,120,61,61,49,41,123,10,9,9,105,102,
+  40,115,99,97,108,101,60,54,53,41,123,10,9,9,9,114,101,116,117,114,110,40,46,
+  55,56,53,51,57,56,49,54,51,51,57,55,52,52,56,51,48,57,54,49,53,54,54,48,56,
+  52,53,56,49,57,56,55,53,55,50,49,48,52,57,50,57,50,51,52,57,56,52,51,55,55,
+  54,52,53,53,50,52,51,55,51,54,49,52,56,48,47,110,41,10,9,9,125,10,9,125,10,
+  9,105,102,40,120,61,61,46,50,41,123,10,9,9,105,102,40,115,99,97,108,101,60,
+  54,53,41,123,10,9,9,9,114,101,116,117,114,110,40,46,49,57,55,51,57,53,53,53,
+  57,56,52,57,56,56,48,55,53,56,51,55,48,48,52,57,55,54,53,49,57,52,55,57,48,
+  50,57,51,52,52,55,53,56,53,49,48,51,55,56,55,56,53,50,49,48,49,53,49,55,54,
+  56,56,57,52,48,50,47,110,41,10,9,9,125,10,9,125,10,9,115,61,115,99,97,108,101,
+  10,9,105,102,40,120,62,46,50,41,123,10,9,9,115,99,97,108,101,43,61,53,10,9,
+  9,97,61,97,40,46,50,41,10,9,125,10,9,115,99,97,108,101,61,115,43,51,10,9,119,
+  104,105,108,101,40,120,62,46,50,41,123,10,9,9,109,43,61,49,10,9,9,120,61,40,
+  120,45,46,50,41,47,40,49,43,46,50,42,120,41,10,9,125,10,9,114,61,117,61,120,
+  10,9,102,61,45,120,42,120,10,9,116,61,49,10,9,102,111,114,40,105,61,51,59,116,
+  33,61,48,59,105,43,61,50,41,123,10,9,9,117,42,61,102,10,9,9,116,61,117,47,105,
+  10,9,9,114,43,61,116,10,9,125,10,9,115,99,97,108,101,61,115,10,9,105,98,97,
+  115,101,61,98,10,9,114,101,116,117,114,110,40,40,109,42,97,43,114,41,47,110,
+  41,10,125,10,100,101,102,105,110,101,32,106,40,110,44,120,41,123,10,9,97,117,
+  116,111,32,98,44,115,44,111,44,97,44,105,44,118,44,102,10,9,98,61,105,98,97,
+  115,101,10,9,105,98,97,115,101,61,65,10,9,115,61,115,99,97,108,101,10,9,115,
+  99,97,108,101,61,48,10,9,110,47,61,49,10,9,105,102,40,110,60,48,41,123,10,9,
+  9,110,61,45,110,10,9,9,105,102,40,110,37,50,61,61,49,41,111,61,49,10,9,125,
+  10,9,97,61,49,10,9,102,111,114,40,105,61,50,59,105,60,61,110,59,43,43,105,41,
+  97,42,61,105,10,9,115,99,97,108,101,61,49,46,53,42,115,10,9,97,61,40,120,94,
+  110,41,47,50,94,110,47,97,10,9,114,61,118,61,49,10,9,102,61,45,120,42,120,47,
+  52,10,9,115,99,97,108,101,61,115,99,97,108,101,43,108,101,110,103,116,104,40,
+  97,41,45,115,99,97,108,101,40,97,41,10,9,102,111,114,40,105,61,49,59,118,33,
+  61,48,59,43,43,105,41,123,10,9,9,118,61,118,42,102,47,105,47,40,110,43,105,
+  41,10,9,9,114,43,61,118,10,9,125,10,9,115,99,97,108,101,61,115,10,9,105,98,
+  97,115,101,61,98,10,9,105,102,40,111,33,61,48,41,97,61,45,97,10,9,114,101,116,
+  117,114,110,40,97,42,114,47,49,41,10,125,10,0
+};
+#endif // ENABLE_BC
+
+static void bc_vec_grow(BcVec *v, size_t n)
+{
+       size_t cap = v->cap * 2;
+       while (cap < v->len + n) cap *= 2;
+       v->v = xrealloc(v->v, v->size * cap);
+       v->cap = cap;
+}
+
+static void bc_vec_init(BcVec *v, size_t esize, BcVecFree dtor)
+{
+       v->size = esize;
+       v->cap = BC_VEC_START_CAP;
+       v->len = 0;
+       v->dtor = dtor;
+       v->v = xmalloc(esize * BC_VEC_START_CAP);
+}
+
+static void bc_vec_expand(BcVec *v, size_t req)
+{
+       if (v->cap < req) {
+               v->v = xrealloc(v->v, v->size * req);
+               v->cap = req;
+       }
+}
+
+static void bc_vec_npop(BcVec *v, size_t n)
+{
+       if (!v->dtor)
+               v->len -= n;
+       else {
+               size_t len = v->len - n;
+               while (v->len > len) v->dtor(v->v + (v->size * --v->len));
+       }
+}
+
+static void bc_vec_push(BcVec *v, const void *data)
+{
+       if (v->len + 1 > v->cap) bc_vec_grow(v, 1);
+       memmove(v->v + (v->size * v->len), data, v->size);
+       v->len += 1;
+}
+
+static void bc_vec_pushByte(BcVec *v, char data)
+{
+       bc_vec_push(v, &data);
+}
+
+static void bc_vec_pushAt(BcVec *v, const void *data, size_t idx)
+{
+       if (idx == v->len)
+               bc_vec_push(v, data);
+       else {
+
+               char *ptr;
+
+               if (v->len == v->cap) bc_vec_grow(v, 1);
+
+               ptr = v->v + v->size * idx;
+
+               memmove(ptr + v->size, ptr, v->size * (v->len++ - idx));
+               memmove(ptr, data, v->size);
+       }
+}
+
+static void bc_vec_string(BcVec *v, size_t len, const char *str)
+{
+       bc_vec_npop(v, v->len);
+       bc_vec_expand(v, len + 1);
+       memcpy(v->v, str, len);
+       v->len = len;
+
+       bc_vec_pushByte(v, '\0');
+}
+
+static void bc_vec_concat(BcVec *v, const char *str)
+{
+       size_t len;
+
+       if (v->len == 0) bc_vec_pushByte(v, '\0');
+
+       len = v->len + strlen(str);
+
+       if (v->cap < len) bc_vec_grow(v, len - v->len);
+       strcat(v->v, str);
+
+       v->len = len;
+}
+
+static void *bc_vec_item(const BcVec *v, size_t idx)
+{
+       return v->v + v->size * idx;
+}
+
+static void *bc_vec_item_rev(const BcVec *v, size_t idx)
+{
+       return v->v + v->size * (v->len - idx - 1);
+}
+
+static void bc_vec_free(void *vec)
+{
+       BcVec *v = (BcVec *) vec;
+       bc_vec_npop(v, v->len);
+       free(v->v);
+}
+
+static size_t bc_map_find(const BcVec *v, const void *ptr)
+{
+       size_t low = 0, high = v->len;
+
+       while (low < high) {
+
+               size_t mid = (low + high) / 2;
+               BcId *id = bc_vec_item(v, mid);
+               int result = bc_id_cmp(ptr, id);
+
+               if (result == 0)
+                       return mid;
+               else if (result < 0)
+                       high = mid;
+               else
+                       low = mid + 1;
+       }
+
+       return low;
+}
+
+static BcStatus bc_map_insert(BcVec *v, const void *ptr, size_t *i)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+
+       *i = bc_map_find(v, ptr);
+
+       if (*i == v->len)
+               bc_vec_push(v, ptr);
+       else if (!bc_id_cmp(ptr, bc_vec_item(v, *i)))
+               s = BC_STATUS_VEC_ITEM_EXISTS;
+       else
+               bc_vec_pushAt(v, ptr, *i);
+
+       return s;
+}
+
+static size_t bc_map_index(const BcVec *v, const void *ptr)
+{
+       size_t i = bc_map_find(v, ptr);
+       if (i >= v->len) return BC_VEC_INVALID_IDX;
+       return bc_id_cmp(ptr, bc_vec_item(v, i)) ? BC_VEC_INVALID_IDX : i;
+}
+
+static BcStatus bc_read_line(BcVec *vec, const char *prompt)
+{
+       int i;
+       signed char c = 0;
+
+       if (bcg.ttyin && !bcg.posix) {
+               bc_vm_puts(prompt, stderr);
+               bc_vm_fflush(stderr);
+       }
+
+       bc_vec_npop(vec, vec->len);
+
+       while (c != '\n') {
+
+               i = fgetc(stdin);
+
+               if (i == EOF) {
+
+#if ENABLE_FEATURE_BC_SIGNALS
+                       if (errno == EINTR) {
+
+                               bcg.sigc = bcg.sig;
+                               bcg.signe = 0;
+
+                               if (bcg.ttyin) {
+                                       bc_vm_puts(bc_program_ready_msg, stderr);
+                                       if (!bcg.posix) bc_vm_puts(prompt, stderr);
+                                       bc_vm_fflush(stderr);
+                               }
+
+                               continue;
+                       }
+#endif // ENABLE_FEATURE_BC_SIGNALS
+
+                       return BC_STATUS_IO_ERR;
+               }
+
+               c = (signed char) i;
+               if (i > UCHAR_MAX || BC_READ_BIN_CHAR(c)) return BC_STATUS_BIN_FILE;
+               bc_vec_push(vec, &c);
+       }
+
+       bc_vec_pushByte(vec, '\0');
+
+       return BC_STATUS_SUCCESS;
+}
+
+static BcStatus bc_read_file(const char *path, char **buf)
+{
+       BcStatus s = BC_STATUS_BIN_FILE;
+       size_t size = ((size_t) -1), read;
+
+       *buf = xmalloc_open_read_close(path, &size);
+
+       for (read = 0; read < size; ++read) {
+               if (BC_READ_BIN_CHAR((*buf)[read])) goto read_err;
+       }
+
+       return BC_STATUS_SUCCESS;
+
+read_err:
+       free(*buf);
+       return s;
+}
+
+#if ENABLE_FEATURE_BC_LONG_OPTIONS
+static const char bc_args_lopt[] ALIGN1 =
+       "extended-register\0"No_argument"x"
+       "warn\0"No_argument"w"
+       "version\0"No_argument"v"
+       "standard\0"No_argument"s"
+       "quiet\0"No_argument"q"
+       "mathlib\0"No_argument"l"
+       "interactive\0"No_argument"i";
+#endif // ENABLE_FEATURE_BC_LONG_OPTIONS
+
+static const char bc_args_opt[] ALIGN1 = "xwvsqli";
+
+static BcStatus bc_args(int argc, char *argv[], uint32_t *flags, BcVec *files)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       int i;
+       bool do_exit = false;
+
+       i = optind = 0;
+
+#if ENABLE_FEATURE_BC_LONG_OPTIONS
+       *flags = getopt32long(argv, bc_args_opt, bc_args_lopt);
+#else // ENABLE_FEATURE_BC_LONG_OPTIONS
+       *flags = getopt32(argv, bc_args_opt);
+#endif // ENABLE_FEATURE_BC_LONG_OPTIONS
+
+       if ((*flags) & BC_FLAG_V) bc_vm_info(NULL);
+       if (do_exit) exit((int) s);
+       if (argv[optind] && !strcmp(argv[optind], "--")) ++optind;
+
+       for (i = optind; i < argc; ++i) bc_vec_push(files, argv + i);
+
+       return s;
+}
+
+static void bc_num_setToZero(BcNum *n, size_t scale)
+{
+       n->len = 0;
+       n->neg = false;
+       n->rdx = scale;
+}
+
+static void bc_num_zero(BcNum *n)
+{
+       bc_num_setToZero(n, 0);
+}
+
+static void bc_num_one(BcNum *n)
+{
+       bc_num_setToZero(n, 0);
+       n->len = 1;
+       n->num[0] = 1;
+}
+
+static void bc_num_ten(BcNum *n)
+{
+       bc_num_setToZero(n, 0);
+       n->len = 2;
+       n->num[0] = 0;
+       n->num[1] = 1;
+}
+
+static BcStatus bc_num_subArrays(BcDig *restrict a, BcDig *restrict b,
+                                 size_t len)
+{
+       size_t i, j;
+       for (i = 0; !bcg.signe && i < len; ++i) {
+               for (a[i] -= b[i], j = 0; !bcg.signe && a[i + j] < 0;) {
+                       a[i + j++] += 10;
+                       a[i + j] -= 1;
+               }
+       }
+       return bcg.signe ? BC_STATUS_EXEC_SIGNAL : BC_STATUS_SUCCESS;
+}
+
+static ssize_t bc_num_compare(BcDig *restrict a, BcDig *restrict b, size_t len)
+{
+       size_t i;
+       int c = 0;
+       for (i = len - 1; !bcg.signe && i < len && !(c = a[i] - b[i]); --i);
+       return BC_NUM_NEG(i + 1, c < 0);
+}
+
+static ssize_t bc_num_cmp(BcNum *a, BcNum *b)
+{
+       size_t i, min, a_int, b_int, diff;
+       BcDig *max_num, *min_num;
+       bool a_max, neg = false;
+       ssize_t cmp;
+
+       if (a == b) return 0;
+       if (a->len == 0) return BC_NUM_NEG(!!b->len, !b->neg);
+       if (b->len == 0) return BC_NUM_NEG(1, a->neg);
+       if (a->neg) {
+               if (b->neg)
+                       neg = true;
+               else
+                       return -1;
+       }
+       else if (b->neg)
+               return 1;
+
+       a_int = BC_NUM_INT(a);
+       b_int = BC_NUM_INT(b);
+       a_int -= b_int;
+       a_max = (a->rdx > b->rdx);
+
+       if (a_int != 0) return (ssize_t) a_int;
+
+       if (a_max) {
+               min = b->rdx;
+               diff = a->rdx - b->rdx;
+               max_num = a->num + diff;
+               min_num = b->num;
+       }
+       else {
+               min = a->rdx;
+               diff = b->rdx - a->rdx;
+               max_num = b->num + diff;
+               min_num = a->num;
+       }
+
+       cmp = bc_num_compare(max_num, min_num, b_int + min);
+       if (cmp != 0) return BC_NUM_NEG(cmp, (!a_max) != neg);
+
+       for (max_num -= diff, i = diff - 1; !bcg.signe && i < diff; --i) {
+               if (max_num[i]) return BC_NUM_NEG(1, (!a_max) != neg);
+       }
+
+       return 0;
+}
+
+static void bc_num_truncate(BcNum *n, size_t places)
+{
+       if (places == 0) return;
+
+       n->rdx -= places;
+
+       if (n->len != 0) {
+               n->len -= places;
+               memmove(n->num, n->num + places, n->len * sizeof(BcDig));
+       }
+}
+
+static void bc_num_extend(BcNum *n, size_t places)
+{
+       size_t len = n->len + places;
+
+       if (places != 0) {
+
+               if (n->cap < len) bc_num_expand(n, len);
+
+               memmove(n->num + places, n->num, sizeof(BcDig) * n->len);
+               memset(n->num, 0, sizeof(BcDig) * places);
+
+               n->len += places;
+               n->rdx += places;
+       }
+}
+
+static void bc_num_clean(BcNum *n)
+{
+       while (n->len > 0 && n->num[n->len - 1] == 0) --n->len;
+       if (n->len == 0)
+               n->neg = false;
+       else if (n->len < n->rdx)
+               n->len = n->rdx;
+}
+
+static void bc_num_retireMul(BcNum *n, size_t scale, bool neg1, bool neg2)
+{
+       if (n->rdx < scale)
+               bc_num_extend(n, scale - n->rdx);
+       else
+               bc_num_truncate(n, n->rdx - scale);
+
+       bc_num_clean(n);
+       if (n->len != 0) n->neg = !neg1 != !neg2;
+}
+
+static void bc_num_split(BcNum *restrict n, size_t idx, BcNum *restrict a,
+                         BcNum *restrict b)
+{
+       if (idx < n->len) {
+
+               b->len = n->len - idx;
+               a->len = idx;
+               a->rdx = b->rdx = 0;
+
+               memcpy(b->num, n->num + idx, b->len * sizeof(BcDig));
+               memcpy(a->num, n->num, idx * sizeof(BcDig));
+       }
+       else {
+               bc_num_zero(b);
+               bc_num_copy(a, n);
+       }
+
+       bc_num_clean(a);
+       bc_num_clean(b);
+}
+
+static BcStatus bc_num_shift(BcNum *n, size_t places)
+{
+       if (places == 0 || n->len == 0) return BC_STATUS_SUCCESS;
+       if (places + n->len > BC_MAX_NUM) return BC_STATUS_EXEC_NUM_LEN;
+
+       if (n->rdx >= places)
+               n->rdx -= places;
+       else {
+               bc_num_extend(n, places - n->rdx);
+               n->rdx = 0;
+       }
+
+       bc_num_clean(n);
+
+       return BC_STATUS_SUCCESS;
+}
+
+static BcStatus bc_num_inv(BcNum *a, BcNum *b, size_t scale)
+{
+       BcNum one;
+       BcDig num[2];
+
+       one.cap = 2;
+       one.num = num;
+       bc_num_one(&one);
+
+       return bc_num_div(&one, a, b, scale);
+}
+
+static BcStatus bc_num_a(BcNum *a, BcNum *b, BcNum *restrict c, size_t sub)
+{
+       BcDig *ptr, *ptr_a, *ptr_b, *ptr_c;
+       size_t i, max, min_rdx, min_int, diff, a_int, b_int;
+       int carry, in;
+
+       // Because this function doesn't need to use scale (per the bc spec),
+       // I am hijacking it to say whether it's doing an add or a subtract.
+
+       if (a->len == 0) {
+               bc_num_copy(c, b);
+               if (sub && c->len) c->neg = !c->neg;
+               return BC_STATUS_SUCCESS;
+       }
+       else if (b->len == 0) {
+               bc_num_copy(c, a);
+               return BC_STATUS_SUCCESS;
+       }
+
+       c->neg = a->neg;
+       c->rdx = BC_MAX(a->rdx, b->rdx);
+       min_rdx = BC_MIN(a->rdx, b->rdx);
+       c->len = 0;
+
+       if (a->rdx > b->rdx) {
+               diff = a->rdx - b->rdx;
+               ptr = a->num;
+               ptr_a = a->num + diff;
+               ptr_b = b->num;
+       }
+       else {
+               diff = b->rdx - a->rdx;
+               ptr = b->num;
+               ptr_a = a->num;
+               ptr_b = b->num + diff;
+       }
+
+       for (ptr_c = c->num, i = 0; i < diff; ++i, ++c->len) ptr_c[i] = ptr[i];
+
+       ptr_c += diff;
+       a_int = BC_NUM_INT(a);
+       b_int = BC_NUM_INT(b);
+
+       if (a_int > b_int) {
+               min_int = b_int;
+               max = a_int;
+               ptr = ptr_a;
+       }
+       else {
+               min_int = a_int;
+               max = b_int;
+               ptr = ptr_b;
+       }
+
+       for (carry = 0, i = 0; !bcg.signe && i < min_rdx + min_int; ++i, ++c->len) {
+               in = ((int) ptr_a[i]) + ((int) ptr_b[i]) + carry;
+               carry = in / 10;
+               ptr_c[i] = (BcDig)(in % 10);
+       }
+
+       for (; !bcg.signe && i < max + min_rdx; ++i, ++c->len) {
+               in = ((int) ptr[i]) + carry;
+               carry = in / 10;
+               ptr_c[i] = (BcDig)(in % 10);
+       }
+
+       if (carry != 0) c->num[c->len++] = (BcDig) carry;
+
+       return bcg.signe ? BC_STATUS_EXEC_SIGNAL : BC_STATUS_SUCCESS;
+}
+
+static BcStatus bc_num_s(BcNum *a, BcNum *b, BcNum *restrict c, size_t sub)
+{
+       BcStatus s;
+       ssize_t cmp;
+       BcNum *minuend, *subtrahend;
+       size_t start;
+       bool aneg, bneg, neg;
+
+       // Because this function doesn't need to use scale (per the bc spec),
+       // I am hijacking it to say whether it's doing an add or a subtract.
+
+       if (a->len == 0) {
+               bc_num_copy(c, b);
+               if (sub && c->len) c->neg = !c->neg;
+               return BC_STATUS_SUCCESS;
+       }
+       else if (b->len == 0) {
+               bc_num_copy(c, a);
+               return BC_STATUS_SUCCESS;
+       }
+
+       aneg = a->neg;
+       bneg = b->neg;
+       a->neg = b->neg = false;
+
+       cmp = bc_num_cmp(a, b);
+
+       a->neg = aneg;
+       b->neg = bneg;
+
+       if (cmp == 0) {
+               bc_num_setToZero(c, BC_MAX(a->rdx, b->rdx));
+               return BC_STATUS_SUCCESS;
+       }
+       else if (cmp > 0) {
+               neg = a->neg;
+               minuend = a;
+               subtrahend = b;
+       }
+       else {
+               neg = b->neg;
+               if (sub) neg = !neg;
+               minuend = b;
+               subtrahend = a;
+       }
+
+       bc_num_copy(c, minuend);
+       c->neg = neg;
+
+       if (c->rdx < subtrahend->rdx) {
+               bc_num_extend(c, subtrahend->rdx - c->rdx);
+               start = 0;
+       }
+       else
+               start = c->rdx - subtrahend->rdx;
+
+       s = bc_num_subArrays(c->num + start, subtrahend->num, subtrahend->len);
+
+       bc_num_clean(c);
+
+       return s;
+}
+
+static BcStatus bc_num_k(BcNum *restrict a, BcNum *restrict b,
+                         BcNum *restrict c)
+{
+       BcStatus s;
+       int carry;
+       size_t i, j, len, max = BC_MAX(a->len, b->len), max2 = (max + 1) / 2;
+       BcNum l1, h1, l2, h2, m2, m1, z0, z1, z2, temp;
+       bool aone = BC_NUM_ONE(a);
+
+       if (bcg.signe) return BC_STATUS_EXEC_SIGNAL;
+       if (a->len == 0 || b->len == 0) {
+               bc_num_zero(c);
+               return BC_STATUS_SUCCESS;
+       }
+       else if (aone || BC_NUM_ONE(b)) {
+               bc_num_copy(c, aone ? b : a);
+               return BC_STATUS_SUCCESS;
+       }
+
+       if (a->len + b->len < BC_NUM_KARATSUBA_LEN ||
+           a->len < BC_NUM_KARATSUBA_LEN || b->len < BC_NUM_KARATSUBA_LEN)
+       {
+               bc_num_expand(c, a->len + b->len + 1);
+
+               memset(c->num, 0, sizeof(BcDig) * c->cap);
+               c->len = carry = len = 0;
+
+               for (i = 0; !bcg.signe && i < b->len; ++i) {
+
+                       for (j = 0; !bcg.signe && j < a->len; ++j) {
+                               int in = (int) c->num[i + j];
+                               in += ((int) a->num[j]) * ((int) b->num[i]) + carry;
+                               carry = in / 10;
+                               c->num[i + j] = (BcDig)(in % 10);
+                       }
+
+                       c->num[i + j] += (BcDig) carry;
+                       len = BC_MAX(len, i + j + !!carry);
+                       carry = 0;
+               }
+
+               c->len = len;
+
+               return bcg.signe ? BC_STATUS_EXEC_SIGNAL : BC_STATUS_SUCCESS;
+       }
+
+       bc_num_init(&l1, max);
+       bc_num_init(&h1, max);
+       bc_num_init(&l2, max);
+       bc_num_init(&h2, max);
+       bc_num_init(&m1, max);
+       bc_num_init(&m2, max);
+       bc_num_init(&z0, max);
+       bc_num_init(&z1, max);
+       bc_num_init(&z2, max);
+       bc_num_init(&temp, max + max);
+
+       bc_num_split(a, max2, &l1, &h1);
+       bc_num_split(b, max2, &l2, &h2);
+
+       s = bc_num_add(&h1, &l1, &m1, 0);
+       if (s) goto err;
+       s = bc_num_add(&h2, &l2, &m2, 0);
+       if (s) goto err;
+
+       s = bc_num_k(&h1, &h2, &z0);
+       if (s) goto err;
+       s = bc_num_k(&m1, &m2, &z1);
+       if (s) goto err;
+       s = bc_num_k(&l1, &l2, &z2);
+       if (s) goto err;
+
+       s = bc_num_sub(&z1, &z0, &temp, 0);
+       if (s) goto err;
+       s = bc_num_sub(&temp, &z2, &z1, 0);
+       if (s) goto err;
+
+       s = bc_num_shift(&z0, max2 * 2);
+       if (s) goto err;
+       s = bc_num_shift(&z1, max2);
+       if (s) goto err;
+       s = bc_num_add(&z0, &z1, &temp, 0);
+       if (s) goto err;
+       s = bc_num_add(&temp, &z2, c, 0);
+
+err:
+       bc_num_free(&temp);
+       bc_num_free(&z2);
+       bc_num_free(&z1);
+       bc_num_free(&z0);
+       bc_num_free(&m2);
+       bc_num_free(&m1);
+       bc_num_free(&h2);
+       bc_num_free(&l2);
+       bc_num_free(&h1);
+       bc_num_free(&l1);
+       return s;
+}
+
+static BcStatus bc_num_m(BcNum *a, BcNum *b, BcNum *restrict c, size_t scale)
+{
+       BcStatus s;
+       BcNum cpa, cpb;
+       size_t maxrdx = BC_MAX(a->rdx, b->rdx);
+
+       scale = BC_MAX(scale, a->rdx);
+       scale = BC_MAX(scale, b->rdx);
+       scale = BC_MIN(a->rdx + b->rdx, scale);
+       maxrdx = BC_MAX(maxrdx, scale);
+
+       bc_num_init(&cpa, a->len);
+       bc_num_init(&cpb, b->len);
+
+       bc_num_copy(&cpa, a);
+       bc_num_copy(&cpb, b);
+       cpa.neg = cpb.neg = false;
+
+       s = bc_num_shift(&cpa, maxrdx);
+       if (s) goto err;
+       s = bc_num_shift(&cpb, maxrdx);
+       if (s) goto err;
+       s = bc_num_k(&cpa, &cpb, c);
+       if (s) goto err;
+
+       maxrdx += scale;
+       bc_num_expand(c, c->len + maxrdx);
+
+       if (c->len < maxrdx) {
+               memset(c->num + c->len, 0, (c->cap - c->len) * sizeof(BcDig));
+               c->len += maxrdx;
+       }
+
+       c->rdx = maxrdx;
+       bc_num_retireMul(c, scale, a->neg, b->neg);
+
+err:
+       bc_num_free(&cpb);
+       bc_num_free(&cpa);
+       return s;
+}
+
+static BcStatus bc_num_d(BcNum *a, BcNum *b, BcNum *restrict c, size_t scale)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       BcDig *n, *p, q;
+       size_t len, end, i;
+       BcNum cp;
+       bool zero = true;
+
+       if (b->len == 0)
+               return BC_STATUS_MATH_DIVIDE_BY_ZERO;
+       else if (a->len == 0) {
+               bc_num_setToZero(c, scale);
+               return BC_STATUS_SUCCESS;
+       }
+       else if (BC_NUM_ONE(b)) {
+               bc_num_copy(c, a);
+               bc_num_retireMul(c, scale, a->neg, b->neg);
+               return BC_STATUS_SUCCESS;
+       }
+
+       bc_num_init(&cp, BC_NUM_MREQ(a, b, scale));
+       bc_num_copy(&cp, a);
+       len = b->len;
+
+       if (len > cp.len) {
+               bc_num_expand(&cp, len + 2);
+               bc_num_extend(&cp, len - cp.len);
+       }
+
+       if (b->rdx > cp.rdx) bc_num_extend(&cp, b->rdx - cp.rdx);
+       cp.rdx -= b->rdx;
+       if (scale > cp.rdx) bc_num_extend(&cp, scale - cp.rdx);
+
+       if (b->rdx == b->len) {
+               for (i = 0; zero && i < len; ++i) zero = !b->num[len - i - 1];
+               len -= i - 1;
+       }
+
+       if (cp.cap == cp.len) bc_num_expand(&cp, cp.len + 1);
+
+       // We want an extra zero in front to make things simpler.
+       cp.num[cp.len++] = 0;
+       end = cp.len - len;
+
+       bc_num_expand(c, cp.len);
+
+       bc_num_zero(c);
+       memset(c->num + end, 0, (c->cap - end) * sizeof(BcDig));
+       c->rdx = cp.rdx;
+       c->len = cp.len;
+       p = b->num;
+
+       for (i = end - 1; !bcg.signe && !s && i < end; --i) {
+               n = cp.num + i;
+               for (q = 0; (!s && n[len] != 0) || bc_num_compare(n, p, len) >= 0; ++q)
+                       s = bc_num_subArrays(n, p, len);
+               c->num[i] = q;
+       }
+
+       if (!s) bc_num_retireMul(c, scale, a->neg, b->neg);
+       bc_num_free(&cp);
+
+       return s;
+}
+
+static BcStatus bc_num_r(BcNum *a, BcNum *b, BcNum *restrict c,
+                         BcNum *restrict d, size_t scale, size_t ts)
+{
+       BcStatus s;
+       BcNum temp;
+       bool neg;
+
+       if (b->len == 0) return BC_STATUS_MATH_DIVIDE_BY_ZERO;
+
+       if (a->len == 0) {
+               bc_num_setToZero(d, ts);
+               return BC_STATUS_SUCCESS;
+       }
+
+       bc_num_init(&temp, d->cap);
+       bc_num_d(a, b, c, scale);
+
+       if (scale != 0) scale = ts;
+
+       s = bc_num_m(c, b, &temp, scale);
+       if (s) goto err;
+       s = bc_num_sub(a, &temp, d, scale);
+       if (s) goto err;
+
+       if (ts > d->rdx && d->len) bc_num_extend(d, ts - d->rdx);
+
+       neg = d->neg;
+       bc_num_retireMul(d, ts, a->neg, b->neg);
+       d->neg = neg;
+
+err:
+       bc_num_free(&temp);
+       return s;
+}
+
+static BcStatus bc_num_rem(BcNum *a, BcNum *b, BcNum *restrict c, size_t scale)
+{
+       BcStatus s;
+       BcNum c1;
+       size_t ts = BC_MAX(scale + b->rdx, a->rdx), len = BC_NUM_MREQ(a, b, ts);
+
+       bc_num_init(&c1, len);
+       s = bc_num_r(a, b, &c1, c, scale, ts);
+       bc_num_free(&c1);
+
+       return s;
+}
+
+static BcStatus bc_num_p(BcNum *a, BcNum *b, BcNum *restrict c, size_t scale)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       BcNum copy;
+       unsigned long pow;
+       size_t i, powrdx, resrdx;
+       bool neg, zero;
+
+       if (b->rdx) return BC_STATUS_MATH_NON_INTEGER;
+
+       if (b->len == 0) {
+               bc_num_one(c);
+               return BC_STATUS_SUCCESS;
+       }
+       else if (a->len == 0) {
+               bc_num_setToZero(c, scale);
+               return BC_STATUS_SUCCESS;
+       }
+       else if (BC_NUM_ONE(b)) {
+               if (!b->neg)
+                       bc_num_copy(c, a);
+               else
+                       s = bc_num_inv(a, c, scale);
+               return s;
+       }
+
+       neg = b->neg;
+       b->neg = false;
+
+       s = bc_num_ulong(b, &pow);
+       if (s) return s;
+
+       bc_num_init(&copy, a->len);
+       bc_num_copy(&copy, a);
+
+       if (!neg) scale = BC_MIN(a->rdx * pow, BC_MAX(scale, a->rdx));
+
+       b->neg = neg;
+
+       for (powrdx = a->rdx; !bcg.signe && !(pow & 1); pow >>= 1) {
+               powrdx <<= 1;
+               s = bc_num_mul(&copy, &copy, &copy, powrdx);
+               if (s) goto err;
+       }
+
+       if (bcg.signe) {
+               s = BC_STATUS_EXEC_SIGNAL;
+               goto err;
+       }
+
+       bc_num_copy(c, &copy);
+
+       for (resrdx = powrdx, pow >>= 1; !bcg.signe && pow != 0; pow >>= 1) {
+
+               powrdx <<= 1;
+               s = bc_num_mul(&copy, &copy, &copy, powrdx);
+               if (s) goto err;
+
+               if (pow & 1) {
+                       resrdx += powrdx;
+                       s = bc_num_mul(c, &copy, c, resrdx);
+                       if (s) goto err;
+               }
+       }
+
+       if (neg) {
+               s = bc_num_inv(c, c, scale);
+               if (s) goto err;
+       }
+
+       if (bcg.signe) {
+               s = BC_STATUS_EXEC_SIGNAL;
+               goto err;
+       }
+
+       if (c->rdx > scale) bc_num_truncate(c, c->rdx - scale);
+
+       // We can't use bc_num_clean() here.
+       for (zero = true, i = 0; zero && i < c->len; ++i) zero = !c->num[i];
+       if (zero) bc_num_setToZero(c, scale);
+
+err:
+       bc_num_free(&copy);
+       return s;
+}
+
+static BcStatus bc_num_binary(BcNum *a, BcNum *b, BcNum *c, size_t scale,
+                              BcNumBinaryOp op, size_t req)
+{
+       BcStatus s;
+       BcNum num2, *ptr_a, *ptr_b;
+       bool init = false;
+
+       if (c == a) {
+               ptr_a = &num2;
+               memcpy(ptr_a, c, sizeof(BcNum));
+               init = true;
+       }
+       else
+               ptr_a = a;
+
+       if (c == b) {
+               ptr_b = &num2;
+               if (c != a) {
+                       memcpy(ptr_b, c, sizeof(BcNum));
+                       init = true;
+               }
+       }
+       else
+               ptr_b = b;
+
+       if (init)
+               bc_num_init(c, req);
+       else
+               bc_num_expand(c, req);
+
+       s = op(ptr_a, ptr_b, c, scale);
+
+       if (init) bc_num_free(&num2);
+
+       return s;
+}
+
+static bool bc_num_strValid(const char *val, size_t base)
+{
+       BcDig b;
+       bool small, radix = false;
+       size_t i, len = strlen(val);
+
+       if (!len) return true;
+
+       small = base <= 10;
+       b = (BcDig)(small ? base + '0' : base - 10 + 'A');
+
+       for (i = 0; i < len; ++i) {
+
+               BcDig c = val[i];
+
+               if (c == '.') {
+
+                       if (radix) return false;
+
+                       radix = true;
+                       continue;
+               }
+
+               if (c < '0' || (small && c >= b) || (c > '9' && (c < 'A' || c >= b)))
+                       return false;
+       }
+
+       return true;
+}
+
+static void bc_num_parseDecimal(BcNum *n, const char *val)
+{
+       size_t len, i;
+       const char *ptr;
+       bool zero = true;
+
+       for (i = 0; val[i] == '0'; ++i);
+
+       val += i;
+       len = strlen(val);
+       bc_num_zero(n);
+
+       if (len != 0) {
+               for (i = 0; zero && i < len; ++i) zero = val[i] == '0' || val[i] == '.';
+               bc_num_expand(n, len);
+       }
+
+       ptr = strchr(val, '.');
+
+       // Explicitly test for NULL here to produce either a 0 or 1.
+       n->rdx = (size_t)((ptr != NULL) * ((val + len) - (ptr + 1)));
+
+       if (!zero) {
+               for (i = len - 1; i < len; ++n->len, i -= 1 + (i && val[i - 1] == '.'))
+                       n->num[n->len] = val[i] - '0';
+       }
+}
+
+static void bc_num_parseBase(BcNum *n, const char *val, BcNum *base)
+{
+       BcStatus s;
+       BcNum temp, mult, result;
+       BcDig c = '\0';
+       bool zero = true;
+       unsigned long v;
+       size_t i, digits, len = strlen(val);
+
+       bc_num_zero(n);
+
+       for (i = 0; zero && i < len; ++i) zero = (val[i] == '.' || val[i] == '0');
+       if (zero) return;
+
+       bc_num_init(&temp, BC_NUM_DEF_SIZE);
+       bc_num_init(&mult, BC_NUM_DEF_SIZE);
+
+       for (i = 0; i < len; ++i) {
+
+               c = val[i];
+               if (c == '.') break;
+
+               v = (unsigned long) (c <= '9' ? c - '0' : c - 'A' + 10);
+
+               s = bc_num_mul(n, base, &mult, 0);
+               if (s) goto int_err;
+               s = bc_num_ulong2num(&temp, v);
+               if (s) goto int_err;
+               s = bc_num_add(&mult, &temp, n, 0);
+               if (s) goto int_err;
+       }
+
+       if (i == len) {
+               c = val[i];
+               if (c == 0) goto int_err;
+       }
+
+       bc_num_init(&result, base->len);
+       bc_num_zero(&result);
+       bc_num_one(&mult);
+
+       for (i += 1, digits = 0; i < len; ++i, ++digits) {
+
+               c = val[i];
+               if (c == 0) break;
+
+               v = (unsigned long) (c <= '9' ? c - '0' : c - 'A' + 10);
+
+               s = bc_num_mul(&result, base, &result, 0);
+               if (s) goto err;
+               s = bc_num_ulong2num(&temp, v);
+               if (s) goto err;
+               s = bc_num_add(&result, &temp, &result, 0);
+               if (s) goto err;
+               s = bc_num_mul(&mult, base, &mult, 0);
+               if (s) goto err;
+       }
+
+       s = bc_num_div(&result, &mult, &result, digits);
+       if (s) goto err;
+       s = bc_num_add(n, &result, n, digits);
+       if (s) goto err;
+
+       if (n->len != 0) {
+               if (n->rdx < digits) bc_num_extend(n, digits - n->rdx);
+       }
+       else
+               bc_num_zero(n);
+
+err:
+       bc_num_free(&result);
+int_err:
+       bc_num_free(&mult);
+       bc_num_free(&temp);
+}
+
+static void bc_num_printNewline(size_t *nchars, size_t line_len)
+{
+       if (*nchars == line_len - 1) {
+               bc_vm_putchar('\\');
+               bc_vm_putchar('\n');
+               *nchars = 0;
+       }
+}
+
+#ifdef ENABLE_DC
+static void bc_num_printChar(size_t num, size_t width, bool radix,
+                             size_t *nchars, size_t line_len)
+{
+       (void) radix, (void) line_len;
+       bc_vm_putchar((char) num);
+       *nchars = *nchars + width;
+}
+#endif // ENABLE_DC
+
+static void bc_num_printDigits(size_t num, size_t width, bool radix,
+                               size_t *nchars, size_t line_len)
+{
+       size_t exp, pow, div;
+
+       bc_num_printNewline(nchars, line_len);
+       bc_vm_putchar(radix ? '.' : ' ');
+       ++(*nchars);
+
+       bc_num_printNewline(nchars, line_len);
+       for (exp = 0, pow = 1; exp < width - 1; ++exp, pow *= 10);
+
+       for (exp = 0; exp < width; pow /= 10, ++(*nchars), ++exp) {
+               bc_num_printNewline(nchars, line_len);
+               div = num / pow;
+               num -= div * pow;
+               bc_vm_putchar(((char) div) + '0');
+       }
+}
+
+static void bc_num_printHex(size_t num, size_t width, bool radix,
+                            size_t *nchars, size_t line_len)
+{
+       if (radix) {
+               bc_num_printNewline(nchars, line_len);
+               bc_vm_putchar('.');
+               *nchars += 1;
+       }
+
+       bc_num_printNewline(nchars, line_len);
+       bc_vm_putchar(bc_num_hex_digits[num]);
+       *nchars = *nchars + width;
+}
+
+static void bc_num_printDecimal(BcNum *n, size_t *nchars, size_t len)
+{
+       size_t i, rdx = n->rdx - 1;
+
+       if (n->neg) bc_vm_putchar('-');
+       (*nchars) += n->neg;
+
+       for (i = n->len - 1; i < n->len; --i)
+               bc_num_printHex((size_t) n->num[i], 1, i == rdx, nchars, len);
+}
+
+static BcStatus bc_num_printNum(BcNum *n, BcNum *base, size_t width,
+                                size_t *nchars, size_t len, BcNumDigitOp print)
+{
+       BcStatus s;
+       BcVec stack;
+       BcNum intp, fracp, digit, frac_len;
+       unsigned long dig, *ptr;
+       size_t i;
+       bool radix;
+
+       if (n->len == 0) {
+               print(0, width, false, nchars, len);
+               return BC_STATUS_SUCCESS;
+       }
+
+       bc_vec_init(&stack, sizeof(long), NULL);
+       bc_num_init(&intp, n->len);
+       bc_num_init(&fracp, n->rdx);
+       bc_num_init(&digit, width);
+       bc_num_init(&frac_len, BC_NUM_INT(n));
+       bc_num_copy(&intp, n);
+       bc_num_one(&frac_len);
+
+       bc_num_truncate(&intp, intp.rdx);
+       s = bc_num_sub(n, &intp, &fracp, 0);
+       if (s) goto err;
+
+       while (intp.len != 0) {
+               s = bc_num_divmod(&intp, base, &intp, &digit, 0);
+               if (s) goto err;
+               s = bc_num_ulong(&digit, &dig);
+               if (s) goto err;
+               bc_vec_push(&stack, &dig);
+       }
+
+       for (i = 0; i < stack.len; ++i) {
+               ptr = bc_vec_item_rev(&stack, i);
+               print(*ptr, width, false, nchars, len);
+       }
+
+       if (!n->rdx) goto err;
+
+       for (radix = true; frac_len.len <= n->rdx; radix = false) {
+               s = bc_num_mul(&fracp, base, &fracp, n->rdx);
+               if (s) goto err;
+               s = bc_num_ulong(&fracp, &dig);
+               if (s) goto err;
+               s = bc_num_ulong2num(&intp, dig);
+               if (s) goto err;
+               s = bc_num_sub(&fracp, &intp, &fracp, 0);
+               if (s) goto err;
+               print(dig, width, radix, nchars, len);
+               s = bc_num_mul(&frac_len, base, &frac_len, 0);
+               if (s) goto err;
+       }
+
+err:
+       bc_num_free(&frac_len);
+       bc_num_free(&digit);
+       bc_num_free(&fracp);
+       bc_num_free(&intp);
+       bc_vec_free(&stack);
+       return s;
+}
+
+static BcStatus bc_num_printBase(BcNum *n, BcNum *base, size_t base_t,
+                                 size_t *nchars, size_t line_len)
+{
+       BcStatus s;
+       size_t width, i;
+       BcNumDigitOp print;
+       bool neg = n->neg;
+
+       if (neg) bc_vm_putchar('-');
+       (*nchars) += neg;
+
+       n->neg = false;
+
+       if (base_t <= BC_NUM_MAX_IBASE) {
+               width = 1;
+               print = bc_num_printHex;
+       }
+       else {
+               for (i = base_t - 1, width = 0; i != 0; i /= 10, ++width);
+               print = bc_num_printDigits;
+       }
+
+       s = bc_num_printNum(n, base, width, nchars, line_len, print);
+       n->neg = neg;
+
+       return s;
+}
+
+#ifdef ENABLE_DC
+static BcStatus bc_num_stream(BcNum *n, BcNum *base, size_t *nchars, size_t len)
+{
+       return bc_num_printNum(n, base, 1, nchars, len, bc_num_printChar);
+}
+#endif // ENABLE_DC
+
+static void bc_num_init(BcNum *n, size_t req)
+{
+       req = req >= BC_NUM_DEF_SIZE ? req : BC_NUM_DEF_SIZE;
+       memset(n, 0, sizeof(BcNum));
+       n->num = xmalloc(req);
+       n->cap = req;
+}
+
+static void bc_num_expand(BcNum *n, size_t req)
+{
+       req = req >= BC_NUM_DEF_SIZE ? req : BC_NUM_DEF_SIZE;
+       if (req > n->cap) {
+               n->num = xrealloc(n->num, req);
+               n->cap = req;
+       }
+}
+
+static void bc_num_free(void *num)
+{
+       free(((BcNum *) num)->num);
+}
+
+static void bc_num_copy(BcNum *d, BcNum *s)
+{
+       if (d != s) {
+               bc_num_expand(d, s->cap);
+               d->len = s->len;
+               d->neg = s->neg;
+               d->rdx = s->rdx;
+               memcpy(d->num, s->num, sizeof(BcDig) * d->len);
+       }
+}
+
+static BcStatus bc_num_parse(BcNum *n, const char *val, BcNum *base,
+                             size_t base_t)
+{
+       if (!bc_num_strValid(val, base_t)) return BC_STATUS_MATH_BAD_STRING;
+
+       if (base_t == 10)
+               bc_num_parseDecimal(n, val);
+       else
+               bc_num_parseBase(n, val, base);
+
+       return BC_STATUS_SUCCESS;
+}
+
+static BcStatus bc_num_print(BcNum *n, BcNum *base, size_t base_t, bool newline,
+                             size_t *nchars, size_t line_len)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+
+       bc_num_printNewline(nchars, line_len);
+
+       if (n->len == 0) {
+               bc_vm_putchar('0');
+               ++(*nchars);
+       }
+       else if (base_t == 10)
+               bc_num_printDecimal(n, nchars, line_len);
+       else
+               s = bc_num_printBase(n, base, base_t, nchars, line_len);
+
+       if (newline) {
+               bc_vm_putchar('\n');
+               *nchars = 0;
+       }
+
+       return s;
+}
+
+static BcStatus bc_num_ulong(BcNum *n, unsigned long *result)
+{
+       size_t i;
+       unsigned long pow;
+
+       if (n->neg) return BC_STATUS_MATH_NEGATIVE;
+
+       for (*result = 0, pow = 1, i = n->rdx; i < n->len; ++i) {
+
+               unsigned long prev = *result, powprev = pow;
+
+               *result += ((unsigned long) n->num[i]) * pow;
+               pow *= 10;
+
+               if (*result < prev || pow < powprev) return BC_STATUS_MATH_OVERFLOW;
+       }
+
+       return BC_STATUS_SUCCESS;
+}
+
+static BcStatus bc_num_ulong2num(BcNum *n, unsigned long val)
+{
+       size_t len;
+       BcDig *ptr;
+       unsigned long i;
+
+       bc_num_zero(n);
+
+       if (val == 0) return BC_STATUS_SUCCESS;
+
+       for (len = 1, i = ULONG_MAX; i != 0; i /= 10, ++len) bc_num_expand(n, len);
+       for (ptr = n->num, i = 0; val; ++i, ++n->len, val /= 10) ptr[i] = val % 10;
+
+       return BC_STATUS_SUCCESS;
+}
+
+static BcStatus bc_num_add(BcNum *a, BcNum *b, BcNum *c, size_t scale)
+{
+       BcNumBinaryOp op = (!a->neg == !b->neg) ? bc_num_a : bc_num_s;
+       (void) scale;
+       return bc_num_binary(a, b, c, false, op, BC_NUM_AREQ(a, b));
+}
+
+static BcStatus bc_num_sub(BcNum *a, BcNum *b, BcNum *c, size_t scale)
+{
+       BcNumBinaryOp op = (!a->neg == !b->neg) ? bc_num_s : bc_num_a;
+       (void) scale;
+       return bc_num_binary(a, b, c, true, op, BC_NUM_AREQ(a, b));
+}
+
+static BcStatus bc_num_mul(BcNum *a, BcNum *b, BcNum *c, size_t scale)
+{
+       size_t req = BC_NUM_MREQ(a, b, scale);
+       return bc_num_binary(a, b, c, scale, bc_num_m, req);
+}
+
+static BcStatus bc_num_div(BcNum *a, BcNum *b, BcNum *c, size_t scale)
+{
+       size_t req = BC_NUM_MREQ(a, b, scale);
+       return bc_num_binary(a, b, c, scale, bc_num_d, req);
+}
+
+static BcStatus bc_num_mod(BcNum *a, BcNum *b, BcNum *c, size_t scale)
+{
+       size_t req = BC_NUM_MREQ(a, b, scale);
+       return bc_num_binary(a, b, c, scale, bc_num_rem, req);
+}
+
+static BcStatus bc_num_pow(BcNum *a, BcNum *b, BcNum *c, size_t scale)
+{
+       return bc_num_binary(a, b, c, scale, bc_num_p, a->len * b->len + 1);
+}
+
+static BcStatus bc_num_sqrt(BcNum *a, BcNum *restrict b, size_t scale)
+{
+       BcStatus s;
+       BcNum num1, num2, half, f, fprime, *x0, *x1, *temp;
+       size_t pow, len, digs, digs1, resrdx, req, times = 0;
+       ssize_t cmp = 1, cmp1 = SSIZE_MAX, cmp2 = SSIZE_MAX;
+
+       req = BC_MAX(scale, a->rdx) + ((BC_NUM_INT(a) + 1) >> 1) + 1;
+       bc_num_expand(b, req);
+
+       if (a->len == 0) {
+               bc_num_setToZero(b, scale);
+               return BC_STATUS_SUCCESS;
+       }
+       else if (a->neg)
+               return BC_STATUS_MATH_NEGATIVE;
+       else if (BC_NUM_ONE(a)) {
+               bc_num_one(b);
+               bc_num_extend(b, scale);
+               return BC_STATUS_SUCCESS;
+       }
+
+       scale = BC_MAX(scale, a->rdx) + 1;
+       len = a->len + scale;
+
+       bc_num_init(&num1, len);
+       bc_num_init(&num2, len);
+       bc_num_init(&half, BC_NUM_DEF_SIZE);
+
+       bc_num_one(&half);
+       half.num[0] = 5;
+       half.rdx = 1;
+
+       bc_num_init(&f, len);
+       bc_num_init(&fprime, len);
+
+       x0 = &num1;
+       x1 = &num2;
+
+       bc_num_one(x0);
+       pow = BC_NUM_INT(a);
+
+       if (pow) {
+
+               if (pow & 1)
+                       x0->num[0] = 2;
+               else
+                       x0->num[0] = 6;
+
+               pow -= 2 - (pow & 1);
+
+               bc_num_extend(x0, pow);
+
+               // Make sure to move the radix back.
+               x0->rdx -= pow;
+       }
+
+       x0->rdx = digs = digs1 = 0;
+       resrdx = scale + 2;
+       len = BC_NUM_INT(x0) + resrdx - 1;
+
+       while (!bcg.signe && (cmp != 0 || digs < len)) {
+
+               s = bc_num_div(a, x0, &f, resrdx);
+               if (s) goto err;
+               s = bc_num_add(x0, &f, &fprime, resrdx);
+               if (s) goto err;
+               s = bc_num_mul(&fprime, &half, x1, resrdx);
+               if (s) goto err;
+
+               cmp = bc_num_cmp(x1, x0);
+               digs = x1->len - (unsigned long long) llabs(cmp);
+
+               if (cmp == cmp2 && digs == digs1)
+                       times += 1;
+               else
+                       times = 0;
+
+               resrdx += times > 4;
+
+               cmp2 = cmp1;
+               cmp1 = cmp;
+               digs1 = digs;
+
+               temp = x0;
+               x0 = x1;
+               x1 = temp;
+       }
+
+       if (bcg.signe) {
+               s = BC_STATUS_EXEC_SIGNAL;
+               goto err;
+       }
+
+       bc_num_copy(b, x0);
+       scale -= 1;
+       if (b->rdx > scale) bc_num_truncate(b, b->rdx - scale);
+
+err:
+       bc_num_free(&fprime);
+       bc_num_free(&f);
+       bc_num_free(&half);
+       bc_num_free(&num2);
+       bc_num_free(&num1);
+       return s;
+}
+
+static BcStatus bc_num_divmod(BcNum *a, BcNum *b, BcNum *c, BcNum *d,
+                              size_t scale)
+{
+       BcStatus s;
+       BcNum num2, *ptr_a;
+       bool init = false;
+       size_t ts = BC_MAX(scale + b->rdx, a->rdx), len = BC_NUM_MREQ(a, b, ts);
+
+       if (c == a) {
+               memcpy(&num2, c, sizeof(BcNum));
+               ptr_a = &num2;
+               bc_num_init(c, len);
+               init = true;
+       }
+       else {
+               ptr_a = a;
+               bc_num_expand(c, len);
+       }
+
+       s = bc_num_r(ptr_a, b, c, d, scale, ts);
+
+       if (init) bc_num_free(&num2);
+
+       return s;
+}
+
+#ifdef ENABLE_DC
+static BcStatus bc_num_modexp(BcNum *a, BcNum *b, BcNum *c, BcNum *restrict d)
+{
+       BcStatus s;
+       BcNum base, exp, two, temp;
+
+       if (c->len == 0) return BC_STATUS_MATH_DIVIDE_BY_ZERO;
+       if (a->rdx || b->rdx || c->rdx) return BC_STATUS_MATH_NON_INTEGER;
+       if (b->neg) return BC_STATUS_MATH_NEGATIVE;
+
+       bc_num_expand(d, c->len);
+       bc_num_init(&base, c->len);
+       bc_num_init(&exp, b->len);
+       bc_num_init(&two, BC_NUM_DEF_SIZE);
+       bc_num_init(&temp, b->len);
+
+       bc_num_one(&two);
+       two.num[0] = 2;
+       bc_num_one(d);
+
+       s = bc_num_rem(a, c, &base, 0);
+       if (s) goto err;
+       bc_num_copy(&exp, b);
+
+       while (exp.len != 0) {
+
+               s = bc_num_divmod(&exp, &two, &exp, &temp, 0);
+               if (s) goto err;
+
+               if (BC_NUM_ONE(&temp)) {
+                       s = bc_num_mul(d, &base, &temp, 0);
+                       if (s) goto err;
+                       s = bc_num_rem(&temp, c, d, 0);
+                       if (s) goto err;
+               }
+
+               s = bc_num_mul(&base, &base, &temp, 0);
+               if (s) goto err;
+               s = bc_num_rem(&temp, c, &base, 0);
+               if (s) goto err;
+       }
+
+err:
+       bc_num_free(&temp);
+       bc_num_free(&two);
+       bc_num_free(&exp);
+       bc_num_free(&base);
+       return s;
+}
+#endif // ENABLE_DC
+
+static int bc_id_cmp(const void *e1, const void *e2)
+{
+       return strcmp(((const BcId *) e1)->name, ((const BcId *) e2)->name);
+}
+
+static void bc_id_free(void *id)
+{
+       free(((BcId *) id)->name);
+}
+
+static BcStatus bc_func_insert(BcFunc *f, char *name, bool var)
+{
+       BcId a;
+       size_t i;
+
+       for (i = 0; i < f->autos.len; ++i) {
+               if (!strcmp(name, ((BcId *) bc_vec_item(&f->autos, i))->name))
+                       return BC_STATUS_PARSE_DUPLICATE_LOCAL;
+       }
+
+       a.idx = var;
+       a.name = name;
+
+       bc_vec_push(&f->autos, &a);
+
+       return BC_STATUS_SUCCESS;
+}
+
+static void bc_func_init(BcFunc *f)
+{
+       bc_vec_init(&f->code, sizeof(char), NULL);
+       bc_vec_init(&f->autos, sizeof(BcId), bc_id_free);
+       bc_vec_init(&f->labels, sizeof(size_t), NULL);
+       f->nparams = 0;
+}
+
+static void bc_func_free(void *func)
+{
+       BcFunc *f = (BcFunc *) func;
+       bc_vec_free(&f->code);
+       bc_vec_free(&f->autos);
+       bc_vec_free(&f->labels);
+}
+
+static void bc_array_init(BcVec *a, bool nums)
+{
+       if (nums)
+               bc_vec_init(a, sizeof(BcNum), bc_num_free);
+       else
+               bc_vec_init(a, sizeof(BcVec), bc_vec_free);
+       bc_array_expand(a, 1);
+}
+
+static void bc_array_copy(BcVec *d, const BcVec *s)
+{
+       size_t i;
+
+       bc_vec_npop(d, d->len);
+       bc_vec_expand(d, s->cap);
+       d->len = s->len;
+
+       for (i = 0; i < s->len; ++i) {
+               BcNum *dnum = bc_vec_item(d, i), *snum = bc_vec_item(s, i);
+               bc_num_init(dnum, snum->len);
+               bc_num_copy(dnum, snum);
+       }
+}
+
+static void bc_array_expand(BcVec *a, size_t len)
+{
+       BcResultData data;
+
+       if (a->size == sizeof(BcNum) && a->dtor == bc_num_free) {
+               while (len > a->len) {
+                       bc_num_init(&data.n, BC_NUM_DEF_SIZE);
+                       bc_vec_push(a, &data.n);
+               }
+       }
+       else {
+               while (len > a->len) {
+                       bc_array_init(&data.v, true);
+                       bc_vec_push(a, &data.v);
+               }
+       }
+}
+
+static void bc_string_free(void *string)
+{
+       free(*((char **) string));
+}
+
+#ifdef ENABLE_DC
+static void bc_result_copy(BcResult *d, BcResult *src)
+{
+       d->t = src->t;
+
+       switch (d->t) {
+
+               case BC_RESULT_TEMP:
+               case BC_RESULT_IBASE:
+               case BC_RESULT_SCALE:
+               case BC_RESULT_OBASE:
+               {
+                       bc_num_init(&d->d.n, src->d.n.len);
+                       bc_num_copy(&d->d.n, &src->d.n);
+                       break;
+               }
+
+               case BC_RESULT_VAR:
+               case BC_RESULT_ARRAY:
+               case BC_RESULT_ARRAY_ELEM:
+               {
+                       d->d.id.name = xstrdup(src->d.id.name);
+                       break;
+               }
+
+               case BC_RESULT_CONSTANT:
+               case BC_RESULT_LAST:
+               case BC_RESULT_ONE:
+               case BC_RESULT_STR:
+               {
+                       memcpy(&d->d.n, &src->d.n, sizeof(BcNum));
+                       break;
+               }
+       }
+}
+#endif // ENABLE_DC
+
+static void bc_result_free(void *result)
+{
+       BcResult *r = (BcResult *) result;
+
+       switch (r->t) {
+
+               case BC_RESULT_TEMP:
+               case BC_RESULT_IBASE:
+               case BC_RESULT_SCALE:
+               case BC_RESULT_OBASE:
+               {
+                       bc_num_free(&r->d.n);
+                       break;
+               }
+
+               case BC_RESULT_VAR:
+               case BC_RESULT_ARRAY:
+               case BC_RESULT_ARRAY_ELEM:
+               {
+                       free(r->d.id.name);
+                       break;
+               }
+
+               default:
+               {
+                       // Do nothing.
+                       break;
+               }
+       }
+}
+
+static void bc_lex_lineComment(BcLex *l)
+{
+       l->t.t = BC_LEX_WHITESPACE;
+       while (l->i < l->len && l->buf[l->i++] != '\n');
+       --l->i;
+}
+
+static void bc_lex_whitespace(BcLex *l)
+{
+       char c;
+       l->t.t = BC_LEX_WHITESPACE;
+       for (c = l->buf[l->i]; c != '\n' && isspace(c); c = l->buf[++l->i]);
+}
+
+static BcStatus bc_lex_number(BcLex *l, char start)
+{
+       const char *buf = l->buf + l->i;
+       size_t len, hits = 0, bslashes = 0, i = 0, j;
+       char c = buf[i];
+       bool last_pt, pt = start == '.';
+
+       last_pt = pt;
+       l->t.t = BC_LEX_NUMBER;
+
+       while (c != 0 && (isdigit(c) || (c >= 'A' && c <= 'F') ||
+                         (c == '.' && !pt) || (c == '\\' && buf[i + 1] == '\n')))
+       {
+               if (c != '\\') {
+                       last_pt = c == '.';
+                       pt = pt || last_pt;
+               }
+               else {
+                       ++i;
+                       bslashes += 1;
+               }
+
+               c = buf[++i];
+       }
+
+       len = i + 1 * !last_pt - bslashes * 2;
+       if (len > BC_MAX_NUM) return BC_STATUS_EXEC_NUM_LEN;
+
+       bc_vec_npop(&l->t.v, l->t.v.len);
+       bc_vec_expand(&l->t.v, len + 1);
+       bc_vec_push(&l->t.v, &start);
+
+       for (buf -= 1, j = 1; j < len + hits * 2; ++j) {
+
+               c = buf[j];
+
+               // If we have hit a backslash, skip it. We don't have
+               // to check for a newline because it's guaranteed.
+               if (hits < bslashes && c == '\\') {
+                       ++hits;
+                       ++j;
+                       continue;
+               }
+
+               bc_vec_push(&l->t.v, &c);
+       }
+
+       bc_vec_pushByte(&l->t.v, '\0');
+       l->i += i;
+
+       return BC_STATUS_SUCCESS;
+}
+
+static BcStatus bc_lex_name(BcLex *l)
+{
+       size_t i = 0;
+       const char *buf = l->buf + l->i - 1;
+       char c = buf[i];
+
+       l->t.t = BC_LEX_NAME;
+
+       while ((c >= 'a' && c <= 'z') || isdigit(c) || c == '_') c = buf[++i];
+
+       if (i > BC_MAX_STRING) return BC_STATUS_EXEC_NAME_LEN;
+       bc_vec_string(&l->t.v, i, buf);
+
+       // Increment the index. We minus 1 because it has already been incremented.
+       l->i += i - 1;
+
+       return BC_STATUS_SUCCESS;
+}
+
+static void bc_lex_init(BcLex *l, BcLexNext next)
+{
+       l->next = next;
+       bc_vec_init(&l->t.v, sizeof(char), NULL);
+}
+
+static void bc_lex_free(BcLex *l)
+{
+       bc_vec_free(&l->t.v);
+}
+
+static void bc_lex_file(BcLex *l, const char *file)
+{
+       l->line = 1;
+       l->newline = false;
+       l->f = file;
+}
+
+static BcStatus bc_lex_next(BcLex *l)
+{
+       BcStatus s;
+
+       l->t.last = l->t.t;
+       if (l->t.last == BC_LEX_EOF) return BC_STATUS_LEX_EOF;
+
+       l->line += l->newline;
+       l->t.t = BC_LEX_EOF;
+
+       l->newline = (l->i == l->len);
+       if (l->newline) return BC_STATUS_SUCCESS;
+
+       // Loop until failure or we don't have whitespace. This
+       // is so the parser doesn't get inundated with whitespace.
+       do {
+               s = l->next(l);
+       } while (!s && l->t.t == BC_LEX_WHITESPACE);
+
+       return s;
+}
+
+static BcStatus bc_lex_text(BcLex *l, const char *text)
+{
+       l->buf = text;
+       l->i = 0;
+       l->len = strlen(text);
+       l->t.t = l->t.last = BC_LEX_INVALID;
+       return bc_lex_next(l);
+}
+
+#ifdef ENABLE_BC
+static BcStatus bc_lex_identifier(BcLex *l)
+{
+       BcStatus s;
+       size_t i;
+       const char *buf = l->buf + l->i - 1;
+
+       for (i = 0; i < sizeof(bc_lex_kws) / sizeof(bc_lex_kws[0]); ++i) {
+
+               unsigned long len = (unsigned long) bc_lex_kws[i].len;
+
+               if (strncmp(buf, bc_lex_kws[i].name, len) == 0) {
+
+                       l->t.t = BC_LEX_KEY_AUTO + (BcLexType) i;
+
+                       if (!bc_lex_kws[i].posix) {
+                               s = bc_vm_posixError(BC_STATUS_POSIX_BAD_KW, l->f, l->line,
+                                                    bc_lex_kws[i].name);
+                               if (s) return s;
+                       }
+
+                       // We minus 1 because the index has already been incremented.
+                       l->i += len - 1;
+                       return BC_STATUS_SUCCESS;
+               }
+       }
+
+       s = bc_lex_name(l);
+       if (s) return s;
+
+       if (l->t.v.len - 1 > 1)
+               s = bc_vm_posixError(BC_STATUS_POSIX_NAME_LEN, l->f, l->line, buf);
+
+       return s;
+}
+
+static BcStatus bc_lex_string(BcLex *l)
+{
+       size_t len, nls = 0, i = l->i;
+       char c;
+
+       l->t.t = BC_LEX_STR;
+
+       for (c = l->buf[i]; c != 0 && c != '"'; c = l->buf[++i]) nls += (c == '\n');
+
+       if (c == '\0') {
+               l->i = i;
+               return BC_STATUS_LEX_NO_STRING_END;
+       }
+
+       len = i - l->i;
+       if (len > BC_MAX_STRING) return BC_STATUS_EXEC_STRING_LEN;
+       bc_vec_string(&l->t.v, len, l->buf + l->i);
+
+       l->i = i + 1;
+       l->line += nls;
+
+       return BC_STATUS_SUCCESS;
+}
+
+static void bc_lex_assign(BcLex *l, BcLexType with, BcLexType without)
+{
+       if (l->buf[l->i] == '=') {
+               ++l->i;
+               l->t.t = with;
+       }
+       else
+               l->t.t = without;
+}
+
+static BcStatus bc_lex_comment(BcLex *l)
+{
+       size_t i, nls = 0;
+       const char *buf = l->buf;
+       bool end = false;
+       char c;
+
+       l->t.t = BC_LEX_WHITESPACE;
+
+       for (i = ++l->i; !end; i += !end) {
+
+               for (c = buf[i]; c != '*' && c != 0; c = buf[++i]) nls += (c == '\n');
+
+               if (c == 0 || buf[i + 1] == '\0') {
+                       l->i = i;
+                       return BC_STATUS_LEX_NO_COMMENT_END;
+               }
+
+               end = buf[i + 1] == '/';
+       }
+
+       l->i = i + 2;
+       l->line += nls;
+
+       return BC_STATUS_SUCCESS;
+}
+
+static BcStatus bc_lex_token(BcLex *l)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       char c = l->buf[l->i++], c2;
+
+       // This is the workhorse of the lexer.
+       switch (c) {
+
+               case '\0':
+               case '\n':
+               {
+                       l->newline = true;
+                       l->t.t = !c ? BC_LEX_EOF : BC_LEX_NLINE;
+                       break;
+               }
+
+               case '\t':
+               case '\v':
+               case '\f':
+               case '\r':
+               case ' ':
+               {
+                       bc_lex_whitespace(l);
+                       break;
+               }
+
+               case '!':
+               {
+                       bc_lex_assign(l, BC_LEX_OP_REL_NE, BC_LEX_OP_BOOL_NOT);
+
+                       if (l->t.t == BC_LEX_OP_BOOL_NOT) {
+                               s = bc_vm_posixError(BC_STATUS_POSIX_BOOL, l->f, l->line, "!");
+                               if (s) return s;
+                       }
+
+                       break;
+               }
+
+               case '"':
+               {
+                       s = bc_lex_string(l);
+                       break;
+               }
+
+               case '#':
+               {
+                       s = bc_vm_posixError(BC_STATUS_POSIX_COMMENT, l->f, l->line, NULL);
+                       if (s) return s;
+
+                       bc_lex_lineComment(l);
+
+                       break;
+               }
+
+               case '%':
+               {
+                       bc_lex_assign(l, BC_LEX_OP_ASSIGN_MODULUS, BC_LEX_OP_MODULUS);
+                       break;
+               }
+
+               case '&':
+               {
+                       c2 = l->buf[l->i];
+                       if (c2 == '&') {
+
+                               s = bc_vm_posixError(BC_STATUS_POSIX_BOOL, l->f, l->line, "&&");
+                               if (s) return s;
+
+                               ++l->i;
+                               l->t.t = BC_LEX_OP_BOOL_AND;
+                       }
+                       else {
+                               l->t.t = BC_LEX_INVALID;
+                               s = BC_STATUS_LEX_BAD_CHAR;
+                       }
+
+                       break;
+               }
+
+               case '(':
+               case ')':
+               {
+                       l->t.t = (BcLexType)(c - '(' + BC_LEX_LPAREN);
+                       break;
+               }
+
+               case '*':
+               {
+                       bc_lex_assign(l, BC_LEX_OP_ASSIGN_MULTIPLY, BC_LEX_OP_MULTIPLY);
+                       break;
+               }
+
+               case '+':
+               {
+                       c2 = l->buf[l->i];
+                       if (c2 == '+') {
+                               ++l->i;
+                               l->t.t = BC_LEX_OP_INC;
+                       }
+                       else
+                               bc_lex_assign(l, BC_LEX_OP_ASSIGN_PLUS, BC_LEX_OP_PLUS);
+                       break;
+               }
+
+               case ',':
+               {
+                       l->t.t = BC_LEX_COMMA;
+                       break;
+               }
+
+               case '-':
+               {
+                       c2 = l->buf[l->i];
+                       if (c2 == '-') {
+                               ++l->i;
+                               l->t.t = BC_LEX_OP_DEC;
+                       }
+                       else
+                               bc_lex_assign(l, BC_LEX_OP_ASSIGN_MINUS, BC_LEX_OP_MINUS);
+                       break;
+               }
+
+               case '.':
+               {
+                       if (isdigit(l->buf[l->i]))
+                               s = bc_lex_number(l, c);
+                       else {
+                               l->t.t = BC_LEX_KEY_LAST;
+                               s = bc_vm_posixError(BC_STATUS_POSIX_DOT, l->f, l->line, NULL);
+                       }
+                       break;
+               }
+
+               case '/':
+               {
+                       c2 = l->buf[l->i];
+                       if (c2 == '*')
+                               s = bc_lex_comment(l);
+                       else
+                               bc_lex_assign(l, BC_LEX_OP_ASSIGN_DIVIDE, BC_LEX_OP_DIVIDE);
+                       break;
+               }
+
+               case '0':
+               case '1':
+               case '2':
+               case '3':
+               case '4':
+               case '5':
+               case '6':
+               case '7':
+               case '8':
+               case '9':
+               case 'A':
+               case 'B':
+               case 'C':
+               case 'D':
+               case 'E':
+               case 'F':
+               {
+                       s = bc_lex_number(l, c);
+                       break;
+               }
+
+               case ';':
+               {
+                       l->t.t = BC_LEX_SCOLON;
+                       break;
+               }
+
+               case '<':
+               {
+                       bc_lex_assign(l, BC_LEX_OP_REL_LE, BC_LEX_OP_REL_LT);
+                       break;
+               }
+
+               case '=':
+               {
+                       bc_lex_assign(l, BC_LEX_OP_REL_EQ, BC_LEX_OP_ASSIGN);
+                       break;
+               }
+
+               case '>':
+               {
+                       bc_lex_assign(l, BC_LEX_OP_REL_GE, BC_LEX_OP_REL_GT);
+                       break;
+               }
+
+               case '[':
+               case ']':
+               {
+                       l->t.t = (BcLexType)(c - '[' + BC_LEX_LBRACKET);
+                       break;
+               }
+
+               case '\\':
+               {
+                       if (l->buf[l->i] == '\n') {
+                               l->t.t = BC_LEX_WHITESPACE;
+                               ++l->i;
+                       }
+                       else
+                               s = BC_STATUS_LEX_BAD_CHAR;
+                       break;
+               }
+
+               case '^':
+               {
+                       bc_lex_assign(l, BC_LEX_OP_ASSIGN_POWER, BC_LEX_OP_POWER);
+                       break;
+               }
+
+               case 'a':
+               case 'b':
+               case 'c':
+               case 'd':
+               case 'e':
+               case 'f':
+               case 'g':
+               case 'h':
+               case 'i':
+               case 'j':
+               case 'k':
+               case 'l':
+               case 'm':
+               case 'n':
+               case 'o':
+               case 'p':
+               case 'q':
+               case 'r':
+               case 's':
+               case 't':
+               case 'u':
+               case 'v':
+               case 'w':
+               case 'x':
+               case 'y':
+               case 'z':
+               {
+                       s = bc_lex_identifier(l);
+                       break;
+               }
+
+               case '{':
+               case '}':
+               {
+                       l->t.t = (BcLexType)(c - '{' + BC_LEX_LBRACE);
+                       break;
+               }
+
+               case '|':
+               {
+                       c2 = l->buf[l->i];
+
+                       if (c2 == '|') {
+
+                               s = bc_vm_posixError(BC_STATUS_POSIX_BOOL, l->f, l->line, "||");
+                               if (s) return s;
+
+                               ++l->i;
+                               l->t.t = BC_LEX_OP_BOOL_OR;
+                       }
+                       else {
+                               l->t.t = BC_LEX_INVALID;
+                               s = BC_STATUS_LEX_BAD_CHAR;
+                       }
+
+                       break;
+               }
+
+               default:
+               {
+                       l->t.t = BC_LEX_INVALID;
+                       s = BC_STATUS_LEX_BAD_CHAR;
+                       break;
+               }
+       }
+
+       return s;
+}
+#endif // ENABLE_BC
+
+#ifdef ENABLE_DC
+static BcStatus dc_lex_register(BcLex *l)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+
+       if (isspace(l->buf[l->i - 1])) {
+               bc_lex_whitespace(l);
+               ++l->i;
+               if (!bcg.exreg)
+                       s = BC_STATUS_LEX_EXTENDED_REG;
+               else
+                       s = bc_lex_name(l);
+       }
+       else {
+               bc_vec_npop(&l->t.v, l->t.v.len);
+               bc_vec_pushByte(&l->t.v, l->buf[l->i - 1]);
+               bc_vec_pushByte(&l->t.v, '\0');
+               l->t.t = BC_LEX_NAME;
+       }
+
+       return s;
+}
+
+static BcStatus dc_lex_string(BcLex *l)
+{
+       size_t depth = 1, nls = 0, i = l->i;
+       char c;
+
+       l->t.t = BC_LEX_STR;
+       bc_vec_npop(&l->t.v, l->t.v.len);
+
+       for (c = l->buf[i]; c != 0 && depth; c = l->buf[++i]) {
+
+               depth += (c == '[' && (i == l->i || l->buf[i - 1] != '\\'));
+               depth -= (c == ']' && (i == l->i || l->buf[i - 1] != '\\'));
+               nls += (c == '\n');
+
+               if (depth) bc_vec_push(&l->t.v, &c);
+       }
+
+       if (c == '\0') {
+               l->i = i;
+               return BC_STATUS_LEX_NO_STRING_END;
+       }
+
+       bc_vec_pushByte(&l->t.v, '\0');
+       if (i - l->i > BC_MAX_STRING) return BC_STATUS_EXEC_STRING_LEN;
+
+       l->i = i;
+       l->line += nls;
+
+       return BC_STATUS_SUCCESS;
+}
+
+static BcStatus dc_lex_token(BcLex *l)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       char c = l->buf[l->i++], c2;
+       size_t i;
+
+       for (i = 0; i < dc_lex_regs_len; ++i) {
+               if (l->t.last == dc_lex_regs[i]) return dc_lex_register(l);
+       }
+
+       if (c >= '%' && c <= '~' &&
+           (l->t.t = dc_lex_tokens[(c - '%')]) != BC_LEX_INVALID)
+       {
+               return s;
+       }
+
+       // This is the workhorse of the lexer.
+       switch (c) {
+
+               case '\0':
+               {
+                       l->t.t = BC_LEX_EOF;
+                       break;
+               }
+
+               case '\n':
+               case '\t':
+               case '\v':
+               case '\f':
+               case '\r':
+               case ' ':
+               {
+                       l->newline = (c == '\n');
+                       bc_lex_whitespace(l);
+                       break;
+               }
+
+               case '!':
+               {
+                       c2 = l->buf[l->i];
+
+                       if (c2 == '=')
+                               l->t.t = BC_LEX_OP_REL_NE;
+                       else if (c2 == '<')
+                               l->t.t = BC_LEX_OP_REL_LE;
+                       else if (c2 == '>')
+                               l->t.t = BC_LEX_OP_REL_GE;
+                       else
+                               return BC_STATUS_LEX_BAD_CHAR;
+
+                       ++l->i;
+                       break;
+               }
+
+               case '#':
+               {
+                       bc_lex_lineComment(l);
+                       break;
+               }
+
+               case '.':
+               {
+                       if (isdigit(l->buf[l->i]))
+                               s = bc_lex_number(l, c);
+                       else
+                               s = BC_STATUS_LEX_BAD_CHAR;
+                       break;
+               }
+
+               case '0':
+               case '1':
+               case '2':
+               case '3':
+               case '4':
+               case '5':
+               case '6':
+               case '7':
+               case '8':
+               case '9':
+               case 'A':
+               case 'B':
+               case 'C':
+               case 'D':
+               case 'E':
+               case 'F':
+               {
+                       s = bc_lex_number(l, c);
+                       break;
+               }
+
+               case '[':
+               {
+                       s = dc_lex_string(l);
+                       break;
+               }
+
+               default:
+               {
+                       l->t.t = BC_LEX_INVALID;
+                       s = BC_STATUS_LEX_BAD_CHAR;
+                       break;
+               }
+       }
+
+       return s;
+}
+#endif // ENABLE_DC
+
+static void bc_parse_addFunc(BcParse *p, char *name, size_t *idx)
+{
+       bc_program_addFunc(p->prog, name, idx);
+       p->func = bc_vec_item(&p->prog->fns, p->fidx);
+}
+
+static void bc_parse_pushName(BcParse *p, char *name)
+{
+       size_t i = 0, len = strlen(name);
+
+       for (; i < len; ++i) bc_parse_push(p, name[i]);
+       bc_parse_push(p, BC_PARSE_STREND);
+
+       free(name);
+}
+
+static void bc_parse_pushIndex(BcParse *p, size_t idx)
+{
+       unsigned char amt, i, nums[sizeof(size_t)];
+
+       for (amt = 0; idx; ++amt) {
+               nums[amt] = (char) idx;
+               idx = (idx & ((unsigned long) ~(UCHAR_MAX))) >> sizeof(char) * CHAR_BIT;
+       }
+
+       bc_parse_push(p, amt);
+       for (i = 0; i < amt; ++i) bc_parse_push(p, nums[i]);
+}
+
+static void bc_parse_number(BcParse *p, BcInst *prev, size_t *nexs)
+{
+       char *num = xstrdup(p->l.t.v.v);
+       size_t idx = p->prog->consts.len;
+
+       bc_vec_push(&p->prog->consts, &num);
+
+       bc_parse_push(p, BC_INST_NUM);
+       bc_parse_pushIndex(p, idx);
+
+       ++(*nexs);
+       (*prev) = BC_INST_NUM;
+}
+
+static BcStatus bc_parse_text(BcParse *p, const char *text)
+{
+       BcStatus s;
+
+       p->func = bc_vec_item(&p->prog->fns, p->fidx);
+
+       if (!strcmp(text, "") && !BC_PARSE_CAN_EXEC(p)) {
+               p->l.t.t = BC_LEX_INVALID;
+               s = p->parse(p);
+               if (s) return s;
+               if (!BC_PARSE_CAN_EXEC(p)) return BC_STATUS_EXEC_FILE_NOT_EXECUTABLE;
+       }
+
+       return bc_lex_text(&p->l, text);
+}
+
+static BcStatus bc_parse_reset(BcParse *p, BcStatus s)
+{
+       if (p->fidx != BC_PROG_MAIN) {
+
+               p->func->nparams = 0;
+               bc_vec_npop(&p->func->code, p->func->code.len);
+               bc_vec_npop(&p->func->autos, p->func->autos.len);
+               bc_vec_npop(&p->func->labels, p->func->labels.len);
+
+               bc_parse_updateFunc(p, BC_PROG_MAIN);
+       }
+
+       p->l.i = p->l.len;
+       p->l.t.t = BC_LEX_EOF;
+       p->auto_part = (p->nbraces = 0);
+
+       bc_vec_npop(&p->flags, p->flags.len - 1);
+       bc_vec_npop(&p->exits, p->exits.len);
+       bc_vec_npop(&p->conds, p->conds.len);
+       bc_vec_npop(&p->ops, p->ops.len);
+
+       return bc_program_reset(p->prog, s);
+}
+
+static void bc_parse_free(BcParse *p)
+{
+       bc_vec_free(&p->flags);
+       bc_vec_free(&p->exits);
+       bc_vec_free(&p->conds);
+       bc_vec_free(&p->ops);
+       bc_lex_free(&p->l);
+}
+
+static void bc_parse_create(BcParse *p, BcProgram *prog, size_t func,
+                            BcParseParse parse, BcLexNext next)
+{
+       memset(p, 0, sizeof(BcParse));
+
+       bc_lex_init(&p->l, next);
+       bc_vec_init(&p->flags, sizeof(uint8_t), NULL);
+       bc_vec_init(&p->exits, sizeof(BcInstPtr), NULL);
+       bc_vec_init(&p->conds, sizeof(size_t), NULL);
+       bc_vec_pushByte(&p->flags, 0);
+       bc_vec_init(&p->ops, sizeof(BcLexType), NULL);
+
+       p->parse = parse;
+       p->prog = prog;
+       p->auto_part = (p->nbraces = 0);
+       bc_parse_updateFunc(p, func);
+}
+
+#ifdef ENABLE_BC
+static BcStatus bc_parse_else(BcParse *p);
+static BcStatus bc_parse_stmt(BcParse *p);
+
+static BcStatus bc_parse_operator(BcParse *p, BcLexType type, size_t start,
+                                  size_t *nexprs, bool next)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       BcLexType t;
+       char l, r = bc_parse_ops[type - BC_LEX_OP_INC].prec;
+       bool left = bc_parse_ops[type - BC_LEX_OP_INC].left;
+
+       while (p->ops.len > start) {
+
+               t = BC_PARSE_TOP_OP(p);
+               if (t == BC_LEX_LPAREN) break;
+
+               l = bc_parse_ops[t - BC_LEX_OP_INC].prec;
+               if (l >= r && (l != r || !left)) break;
+
+               bc_parse_push(p, BC_PARSE_TOKEN_INST(t));
+               bc_vec_pop(&p->ops);
+               *nexprs -= t != BC_LEX_OP_BOOL_NOT && t != BC_LEX_NEG;
+       }
+
+       bc_vec_push(&p->ops, &type);
+       if (next) s = bc_lex_next(&p->l);
+
+       return s;
+}
+
+static BcStatus bc_parse_rightParen(BcParse *p, size_t ops_bgn, size_t *nexs)
+{
+       BcLexType top;
+
+       if (p->ops.len <= ops_bgn) return BC_STATUS_PARSE_BAD_EXP;
+       top = BC_PARSE_TOP_OP(p);
+
+       while (top != BC_LEX_LPAREN) {
+
+               bc_parse_push(p, BC_PARSE_TOKEN_INST(top));
+
+               bc_vec_pop(&p->ops);
+               *nexs -= top != BC_LEX_OP_BOOL_NOT && top != BC_LEX_NEG;
+
+               if (p->ops.len <= ops_bgn) return BC_STATUS_PARSE_BAD_EXP;
+               top = BC_PARSE_TOP_OP(p);
+       }
+
+       bc_vec_pop(&p->ops);
+
+       return bc_lex_next(&p->l);
+}
+
+static BcStatus bc_parse_params(BcParse *p, uint8_t flags)
+{
+       BcStatus s;
+       bool comma = false;
+       size_t nparams;
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+
+       for (nparams = 0; p->l.t.t != BC_LEX_RPAREN; ++nparams) {
+
+               flags = (flags & ~(BC_PARSE_PRINT | BC_PARSE_REL)) | BC_PARSE_ARRAY;
+               s = bc_parse_expr(p, flags, bc_parse_next_param);
+               if (s) return s;
+
+               comma = p->l.t.t == BC_LEX_COMMA;
+               if (comma) {
+                       s = bc_lex_next(&p->l);
+                       if (s) return s;
+               }
+       }
+
+       if (comma) return BC_STATUS_PARSE_BAD_TOKEN;
+       bc_parse_push(p, BC_INST_CALL);
+       bc_parse_pushIndex(p, nparams);
+
+       return BC_STATUS_SUCCESS;
+}
+
+static BcStatus bc_parse_call(BcParse *p, char *name, uint8_t flags)
+{
+       BcStatus s;
+       BcId entry, *entry_ptr;
+       size_t idx;
+
+       entry.name = name;
+
+       s = bc_parse_params(p, flags);
+       if (s) goto err;
+
+       if (p->l.t.t != BC_LEX_RPAREN) {
+               s = BC_STATUS_PARSE_BAD_TOKEN;
+               goto err;
+       }
+
+       idx = bc_map_index(&p->prog->fn_map, &entry);
+
+       if (idx == BC_VEC_INVALID_IDX) {
+               name = xstrdup(entry.name);
+               bc_parse_addFunc(p, name, &idx);
+               idx = bc_map_index(&p->prog->fn_map, &entry);
+               free(entry.name);
+       }
+       else
+               free(name);
+
+       entry_ptr = bc_vec_item(&p->prog->fn_map, idx);
+       bc_parse_pushIndex(p, entry_ptr->idx);
+
+       return bc_lex_next(&p->l);
+
+err:
+       free(name);
+       return s;
+}
+
+static BcStatus bc_parse_name(BcParse *p, BcInst *type, uint8_t flags)
+{
+       BcStatus s;
+       char *name;
+
+       name = xstrdup(p->l.t.v.v);
+       s = bc_lex_next(&p->l);
+       if (s) goto err;
+
+       if (p->l.t.t == BC_LEX_LBRACKET) {
+
+               s = bc_lex_next(&p->l);
+               if (s) goto err;
+
+               if (p->l.t.t == BC_LEX_RBRACKET) {
+
+                       if (!(flags & BC_PARSE_ARRAY)) {
+                               s = BC_STATUS_PARSE_BAD_EXP;
+                               goto err;
+                       }
+
+                       *type = BC_INST_ARRAY;
+               }
+               else {
+
+                       *type = BC_INST_ARRAY_ELEM;
+
+                       flags &= ~(BC_PARSE_PRINT | BC_PARSE_REL);
+                       s = bc_parse_expr(p, flags, bc_parse_next_elem);
+                       if (s) goto err;
+               }
+
+               s = bc_lex_next(&p->l);
+               if (s) goto err;
+               bc_parse_push(p, *type);
+               bc_parse_pushName(p, name);
+       }
+       else if (p->l.t.t == BC_LEX_LPAREN) {
+
+               if (flags & BC_PARSE_NOCALL) {
+                       s = BC_STATUS_PARSE_BAD_TOKEN;
+                       goto err;
+               }
+
+               *type = BC_INST_CALL;
+               s = bc_parse_call(p, name, flags);
+       }
+       else {
+               *type = BC_INST_VAR;
+               bc_parse_push(p, BC_INST_VAR);
+               bc_parse_pushName(p, name);
+       }
+
+       return s;
+
+err:
+       free(name);
+       return s;
+}
+
+static BcStatus bc_parse_read(BcParse *p)
+{
+       BcStatus s;
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+       if (p->l.t.t != BC_LEX_LPAREN) return BC_STATUS_PARSE_BAD_TOKEN;
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+       if (p->l.t.t != BC_LEX_RPAREN) return BC_STATUS_PARSE_BAD_TOKEN;
+
+       bc_parse_push(p, BC_INST_READ);
+
+       return bc_lex_next(&p->l);
+}
+
+static BcStatus bc_parse_builtin(BcParse *p, BcLexType type, uint8_t flags,
+                                 BcInst *prev)
+{
+       BcStatus s;
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+       if (p->l.t.t != BC_LEX_LPAREN) return BC_STATUS_PARSE_BAD_TOKEN;
+
+       flags = (flags & ~(BC_PARSE_PRINT | BC_PARSE_REL)) | BC_PARSE_ARRAY;
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+
+       s = bc_parse_expr(p, flags, bc_parse_next_rel);
+       if (s) return s;
+
+       if (p->l.t.t != BC_LEX_RPAREN) return BC_STATUS_PARSE_BAD_TOKEN;
+
+       *prev = (type == BC_LEX_KEY_LENGTH) ? BC_INST_LENGTH : BC_INST_SQRT;
+       bc_parse_push(p, *prev);
+
+       return bc_lex_next(&p->l);
+}
+
+static BcStatus bc_parse_scale(BcParse *p, BcInst *type, uint8_t flags)
+{
+       BcStatus s;
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+
+       if (p->l.t.t != BC_LEX_LPAREN) {
+               *type = BC_INST_SCALE;
+               bc_parse_push(p, BC_INST_SCALE);
+               return BC_STATUS_SUCCESS;
+       }
+
+       *type = BC_INST_SCALE_FUNC;
+       flags &= ~(BC_PARSE_PRINT | BC_PARSE_REL);
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+
+       s = bc_parse_expr(p, flags, bc_parse_next_rel);
+       if (s) return s;
+       if (p->l.t.t != BC_LEX_RPAREN) return BC_STATUS_PARSE_BAD_TOKEN;
+       bc_parse_push(p, BC_INST_SCALE_FUNC);
+
+       return bc_lex_next(&p->l);
+}
+
+static BcStatus bc_parse_incdec(BcParse *p, BcInst *prev, bool *paren_expr,
+                                size_t *nexprs, uint8_t flags)
+{
+       BcStatus s;
+       BcLexType type;
+       char inst;
+       BcInst etype = *prev;
+
+       if (etype == BC_INST_VAR || etype == BC_INST_ARRAY_ELEM ||
+           etype == BC_INST_SCALE || etype == BC_INST_LAST ||
+           etype == BC_INST_IBASE || etype == BC_INST_OBASE)
+       {
+               *prev = inst = BC_INST_INC_POST + (p->l.t.t != BC_LEX_OP_INC);
+               bc_parse_push(p, inst);
+               s = bc_lex_next(&p->l);
+       }
+       else {
+
+               *prev = inst = BC_INST_INC_PRE + (p->l.t.t != BC_LEX_OP_INC);
+               *paren_expr = true;
+
+               s = bc_lex_next(&p->l);
+               if (s) return s;
+               type = p->l.t.t;
+
+               // Because we parse the next part of the expression
+               // right here, we need to increment this.
+               *nexprs = *nexprs + 1;
+
+               switch (type) {
+
+                       case BC_LEX_NAME:
+                       {
+                               s = bc_parse_name(p, prev, flags | BC_PARSE_NOCALL);
+                               break;
+                       }
+
+                       case BC_LEX_KEY_IBASE:
+                       case BC_LEX_KEY_LAST:
+                       case BC_LEX_KEY_OBASE:
+                       {
+                               bc_parse_push(p, type - BC_LEX_KEY_IBASE + BC_INST_IBASE);
+                               s = bc_lex_next(&p->l);
+                               break;
+                       }
+
+                       case BC_LEX_KEY_SCALE:
+                       {
+                               s = bc_lex_next(&p->l);
+                               if (s) return s;
+                               if (p->l.t.t == BC_LEX_LPAREN)
+                                       s = BC_STATUS_PARSE_BAD_TOKEN;
+                               else
+                                       bc_parse_push(p, BC_INST_SCALE);
+                               break;
+                       }
+
+                       default:
+                       {
+                               s = BC_STATUS_PARSE_BAD_TOKEN;
+                               break;
+                       }
+               }
+
+               if (!s) bc_parse_push(p, inst);
+       }
+
+       return s;
+}
+
+static BcStatus bc_parse_minus(BcParse *p, BcInst *prev, size_t ops_bgn,
+                               bool rparen, size_t *nexprs)
+{
+       BcStatus s;
+       BcLexType type;
+       BcInst etype = *prev;
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+
+       type = rparen || etype == BC_INST_INC_POST || etype == BC_INST_DEC_POST ||
+                      (etype >= BC_INST_NUM && etype <= BC_INST_SQRT) ?
+                  BC_LEX_OP_MINUS :
+                  BC_LEX_NEG;
+       *prev = BC_PARSE_TOKEN_INST(type);
+
+       // We can just push onto the op stack because this is the largest
+       // precedence operator that gets pushed. Inc/dec does not.
+       if (type != BC_LEX_OP_MINUS)
+               bc_vec_push(&p->ops, &type);
+       else
+               s = bc_parse_operator(p, type, ops_bgn, nexprs, false);
+
+       return s;
+}
+
+static BcStatus bc_parse_string(BcParse *p, char inst)
+{
+       char *str = xstrdup(p->l.t.v.v);
+
+       bc_parse_push(p, BC_INST_STR);
+       bc_parse_pushIndex(p, p->prog->strs.len);
+       bc_vec_push(&p->prog->strs, &str);
+       bc_parse_push(p, inst);
+
+       return bc_lex_next(&p->l);
+}
+
+static BcStatus bc_parse_print(BcParse *p)
+{
+       BcStatus s;
+       BcLexType type;
+       bool comma = false;
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+
+       type = p->l.t.t;
+
+       if (type == BC_LEX_SCOLON || type == BC_LEX_NLINE)
+               return BC_STATUS_PARSE_BAD_PRINT;
+
+       while (!s && type != BC_LEX_SCOLON && type != BC_LEX_NLINE) {
+
+               if (type == BC_LEX_STR)
+                       s = bc_parse_string(p, BC_INST_PRINT_POP);
+               else {
+                       s = bc_parse_expr(p, 0, bc_parse_next_print);
+                       if (s) return s;
+                       bc_parse_push(p, BC_INST_PRINT_POP);
+               }
+
+               if (s) return s;
+
+               comma = p->l.t.t == BC_LEX_COMMA;
+               if (comma) s = bc_lex_next(&p->l);
+               type = p->l.t.t;
+       }
+
+       if (s) return s;
+       if (comma) return BC_STATUS_PARSE_BAD_TOKEN;
+
+       return bc_lex_next(&p->l);
+}
+
+static BcStatus bc_parse_return(BcParse *p)
+{
+       BcStatus s;
+       BcLexType t;
+       bool paren;
+
+       if (!BC_PARSE_FUNC(p)) return BC_STATUS_PARSE_BAD_TOKEN;
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+
+       t = p->l.t.t;
+       paren = t == BC_LEX_LPAREN;
+
+       if (t == BC_LEX_NLINE || t == BC_LEX_SCOLON)
+               bc_parse_push(p, BC_INST_RET0);
+       else {
+
+               s = bc_parse_expr(p, 0, bc_parse_next_expr);
+               if (s && s != BC_STATUS_PARSE_EMPTY_EXP)
+                       return s;
+               else if (s == BC_STATUS_PARSE_EMPTY_EXP) {
+                       bc_parse_push(p, BC_INST_RET0);
+                       s = bc_lex_next(&p->l);
+                       if (s) return s;
+               }
+
+               if (!paren || p->l.t.last != BC_LEX_RPAREN) {
+                       s = bc_vm_posixError(BC_STATUS_POSIX_RET, p->l.f, p->l.line, NULL);
+                       if (s) return s;
+               }
+
+               bc_parse_push(p, BC_INST_RET);
+       }
+
+       return s;
+}
+
+static BcStatus bc_parse_endBody(BcParse *p, bool brace)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+
+       if (p->flags.len <= 1 || (brace && p->nbraces == 0))
+               return BC_STATUS_PARSE_BAD_TOKEN;
+
+       if (brace) {
+
+               if (p->l.t.t == BC_LEX_RBRACE) {
+                       if (!p->nbraces) return BC_STATUS_PARSE_BAD_TOKEN;
+                       --p->nbraces;
+                       s = bc_lex_next(&p->l);
+                       if (s) return s;
+               }
+               else
+                       return BC_STATUS_PARSE_BAD_TOKEN;
+       }
+
+       if (BC_PARSE_IF(p)) {
+
+               uint8_t *flag_ptr;
+
+               while (p->l.t.t == BC_LEX_NLINE) {
+                       s = bc_lex_next(&p->l);
+                       if (s) return s;
+               }
+
+               bc_vec_pop(&p->flags);
+
+               flag_ptr = BC_PARSE_TOP_FLAG_PTR(p);
+               *flag_ptr = (*flag_ptr | BC_PARSE_FLAG_IF_END);
+
+               if (p->l.t.t == BC_LEX_KEY_ELSE) s = bc_parse_else(p);
+       }
+       else if (BC_PARSE_ELSE(p)) {
+
+               BcInstPtr *ip;
+               size_t *label;
+
+               bc_vec_pop(&p->flags);
+
+               ip = bc_vec_top(&p->exits);
+               label = bc_vec_item(&p->func->labels, ip->idx);
+               *label = p->func->code.len;
+
+               bc_vec_pop(&p->exits);
+       }
+       else if (BC_PARSE_FUNC_INNER(p)) {
+               bc_parse_push(p, BC_INST_RET0);
+               bc_parse_updateFunc(p, BC_PROG_MAIN);
+               bc_vec_pop(&p->flags);
+       }
+       else {
+
+               BcInstPtr *ip = bc_vec_top(&p->exits);
+               size_t *label = bc_vec_top(&p->conds);
+
+               bc_parse_push(p, BC_INST_JUMP);
+               bc_parse_pushIndex(p, *label);
+
+               label = bc_vec_item(&p->func->labels, ip->idx);
+               *label = p->func->code.len;
+
+               bc_vec_pop(&p->flags);
+               bc_vec_pop(&p->exits);
+               bc_vec_pop(&p->conds);
+       }
+
+       return s;
+}
+
+static void bc_parse_startBody(BcParse *p, uint8_t flags)
+{
+       uint8_t *flag_ptr = BC_PARSE_TOP_FLAG_PTR(p);
+       flags |= (*flag_ptr & (BC_PARSE_FLAG_FUNC | BC_PARSE_FLAG_LOOP));
+       flags |= BC_PARSE_FLAG_BODY;
+       bc_vec_push(&p->flags, &flags);
+}
+
+static void bc_parse_noElse(BcParse *p)
+{
+       BcInstPtr *ip;
+       size_t *label;
+       uint8_t *flag_ptr = BC_PARSE_TOP_FLAG_PTR(p);
+
+       *flag_ptr = (*flag_ptr & ~(BC_PARSE_FLAG_IF_END));
+
+       ip = bc_vec_top(&p->exits);
+       label = bc_vec_item(&p->func->labels, ip->idx);
+       *label = p->func->code.len;
+
+       bc_vec_pop(&p->exits);
+}
+
+static BcStatus bc_parse_if(BcParse *p)
+{
+       BcStatus s;
+       BcInstPtr ip;
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+       if (p->l.t.t != BC_LEX_LPAREN) return BC_STATUS_PARSE_BAD_TOKEN;
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+       s = bc_parse_expr(p, BC_PARSE_REL, bc_parse_next_rel);
+       if (s) return s;
+       if (p->l.t.t != BC_LEX_RPAREN) return BC_STATUS_PARSE_BAD_TOKEN;
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+       bc_parse_push(p, BC_INST_JUMP_ZERO);
+
+       ip.idx = p->func->labels.len;
+       ip.func = ip.len = 0;
+
+       bc_parse_pushIndex(p, ip.idx);
+       bc_vec_push(&p->exits, &ip);
+       bc_vec_push(&p->func->labels, &ip.idx);
+       bc_parse_startBody(p, BC_PARSE_FLAG_IF);
+
+       return BC_STATUS_SUCCESS;
+}
+
+static BcStatus bc_parse_else(BcParse *p)
+{
+       BcInstPtr ip;
+
+       if (!BC_PARSE_IF_END(p)) return BC_STATUS_PARSE_BAD_TOKEN;
+
+       ip.idx = p->func->labels.len;
+       ip.func = ip.len = 0;
+
+       bc_parse_push(p, BC_INST_JUMP);
+       bc_parse_pushIndex(p, ip.idx);
+
+       bc_parse_noElse(p);
+
+       bc_vec_push(&p->exits, &ip);
+       bc_vec_push(&p->func->labels, &ip.idx);
+       bc_parse_startBody(p, BC_PARSE_FLAG_ELSE);
+
+       return bc_lex_next(&p->l);
+}
+
+static BcStatus bc_parse_while(BcParse *p)
+{
+       BcStatus s;
+       BcInstPtr ip;
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+       if (p->l.t.t != BC_LEX_LPAREN) return BC_STATUS_PARSE_BAD_TOKEN;
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+
+       ip.idx = p->func->labels.len;
+
+       bc_vec_push(&p->func->labels, &p->func->code.len);
+       bc_vec_push(&p->conds, &ip.idx);
+
+       ip.idx = p->func->labels.len;
+       ip.func = 1;
+       ip.len = 0;
+
+       bc_vec_push(&p->exits, &ip);
+       bc_vec_push(&p->func->labels, &ip.idx);
+
+       s = bc_parse_expr(p, BC_PARSE_REL, bc_parse_next_rel);
+       if (s) return s;
+       if (p->l.t.t != BC_LEX_RPAREN) return BC_STATUS_PARSE_BAD_TOKEN;
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+
+       bc_parse_push(p, BC_INST_JUMP_ZERO);
+       bc_parse_pushIndex(p, ip.idx);
+       bc_parse_startBody(p, BC_PARSE_FLAG_LOOP | BC_PARSE_FLAG_LOOP_INNER);
+
+       return BC_STATUS_SUCCESS;
+}
+
+static BcStatus bc_parse_for(BcParse *p)
+{
+       BcStatus s;
+       BcInstPtr ip;
+       size_t cond_idx, exit_idx, body_idx, update_idx;
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+       if (p->l.t.t != BC_LEX_LPAREN) return BC_STATUS_PARSE_BAD_TOKEN;
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+
+       if (p->l.t.t != BC_LEX_SCOLON)
+               s = bc_parse_expr(p, 0, bc_parse_next_for);
+       else
+               s = bc_vm_posixError(BC_STATUS_POSIX_FOR1, p->l.f, p->l.line, NULL);
+
+       if (s) return s;
+       if (p->l.t.t != BC_LEX_SCOLON) return BC_STATUS_PARSE_BAD_TOKEN;
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+
+       cond_idx = p->func->labels.len;
+       update_idx = cond_idx + 1;
+       body_idx = update_idx + 1;
+       exit_idx = body_idx + 1;
+
+       bc_vec_push(&p->func->labels, &p->func->code.len);
+
+       if (p->l.t.t != BC_LEX_SCOLON)
+               s = bc_parse_expr(p, BC_PARSE_REL, bc_parse_next_for);
+       else
+               s = bc_vm_posixError(BC_STATUS_POSIX_FOR2, p->l.f, p->l.line, NULL);
+
+       if (s) return s;
+       if (p->l.t.t != BC_LEX_SCOLON) return BC_STATUS_PARSE_BAD_TOKEN;
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+
+       bc_parse_push(p, BC_INST_JUMP_ZERO);
+       bc_parse_pushIndex(p, exit_idx);
+       bc_parse_push(p, BC_INST_JUMP);
+       bc_parse_pushIndex(p, body_idx);
+
+       ip.idx = p->func->labels.len;
+
+       bc_vec_push(&p->conds, &update_idx);
+       bc_vec_push(&p->func->labels, &p->func->code.len);
+
+       if (p->l.t.t != BC_LEX_RPAREN)
+               s = bc_parse_expr(p, 0, bc_parse_next_rel);
+       else
+               s = bc_vm_posixError(BC_STATUS_POSIX_FOR3, p->l.f, p->l.line, NULL);
+
+       if (s) return s;
+
+       if (p->l.t.t != BC_LEX_RPAREN) return BC_STATUS_PARSE_BAD_TOKEN;
+       bc_parse_push(p, BC_INST_JUMP);
+       bc_parse_pushIndex(p, cond_idx);
+       bc_vec_push(&p->func->labels, &p->func->code.len);
+
+       ip.idx = exit_idx;
+       ip.func = 1;
+       ip.len = 0;
+
+       bc_vec_push(&p->exits, &ip);
+       bc_vec_push(&p->func->labels, &ip.idx);
+       bc_lex_next(&p->l);
+       bc_parse_startBody(p, BC_PARSE_FLAG_LOOP | BC_PARSE_FLAG_LOOP_INNER);
+
+       return BC_STATUS_SUCCESS;
+}
+
+static BcStatus bc_parse_loopExit(BcParse *p, BcLexType type)
+{
+       BcStatus s;
+       size_t i;
+       BcInstPtr *ip;
+
+       if (!BC_PARSE_LOOP(p)) return BC_STATUS_PARSE_BAD_TOKEN;
+
+       if (type == BC_LEX_KEY_BREAK) {
+
+               if (p->exits.len == 0) return BC_STATUS_PARSE_BAD_TOKEN;
+
+               i = p->exits.len - 1;
+               ip = bc_vec_item(&p->exits, i);
+
+               while (!ip->func && i < p->exits.len) ip = bc_vec_item(&p->exits, i--);
+               if (i >= p->exits.len && !ip->func) return BC_STATUS_PARSE_BAD_TOKEN;
+
+               i = ip->idx;
+       }
+       else
+               i = *((size_t *) bc_vec_top(&p->conds));
+
+       bc_parse_push(p, BC_INST_JUMP);
+       bc_parse_pushIndex(p, i);
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+
+       if (p->l.t.t != BC_LEX_SCOLON && p->l.t.t != BC_LEX_NLINE)
+               return BC_STATUS_PARSE_BAD_TOKEN;
+
+       return bc_lex_next(&p->l);
+}
+
+static BcStatus bc_parse_func(BcParse *p)
+{
+       BcStatus s;
+       bool var, comma = false;
+       uint8_t flags;
+       char *name;
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+       if (p->l.t.t != BC_LEX_NAME) return BC_STATUS_PARSE_BAD_FUNC;
+
+       name = xstrdup(p->l.t.v.v);
+       bc_parse_addFunc(p, name, &p->fidx);
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+       if (p->l.t.t != BC_LEX_LPAREN) return BC_STATUS_PARSE_BAD_FUNC;
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+
+       while (p->l.t.t != BC_LEX_RPAREN) {
+
+               if (p->l.t.t != BC_LEX_NAME) return BC_STATUS_PARSE_BAD_FUNC;
+
+               ++p->func->nparams;
+
+               name = xstrdup(p->l.t.v.v);
+               s = bc_lex_next(&p->l);
+               if (s) goto err;
+
+               var = p->l.t.t != BC_LEX_LBRACKET;
+
+               if (!var) {
+
+                       s = bc_lex_next(&p->l);
+                       if (s) goto err;
+
+                       if (p->l.t.t != BC_LEX_RBRACKET) {
+                               s = BC_STATUS_PARSE_BAD_FUNC;
+                               goto err;
+                       }
+
+                       s = bc_lex_next(&p->l);
+                       if (s) goto err;
+               }
+
+               comma = p->l.t.t == BC_LEX_COMMA;
+               if (comma) {
+                       s = bc_lex_next(&p->l);
+                       if (s) goto err;
+               }
+
+               s = bc_func_insert(p->func, name, var);
+               if (s) goto err;
+       }
+
+       if (comma) return BC_STATUS_PARSE_BAD_FUNC;
+
+       flags = BC_PARSE_FLAG_FUNC | BC_PARSE_FLAG_FUNC_INNER | BC_PARSE_FLAG_BODY;
+       bc_parse_startBody(p, flags);
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+
+       if (p->l.t.t != BC_LEX_LBRACE)
+               s = bc_vm_posixError(BC_STATUS_POSIX_BRACE, p->l.f, p->l.line, NULL);
+
+       return s;
+
+err:
+       free(name);
+       return s;
+}
+
+static BcStatus bc_parse_auto(BcParse *p)
+{
+       BcStatus s;
+       bool comma, var, one;
+       char *name;
+
+       if (!p->auto_part) return BC_STATUS_PARSE_BAD_TOKEN;
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+
+       p->auto_part = comma = false;
+       one = p->l.t.t == BC_LEX_NAME;
+
+       while (p->l.t.t == BC_LEX_NAME) {
+
+               name = xstrdup(p->l.t.v.v);
+               s = bc_lex_next(&p->l);
+               if (s) goto err;
+
+               var = p->l.t.t != BC_LEX_LBRACKET;
+               if (!var) {
+
+                       s = bc_lex_next(&p->l);
+                       if (s) goto err;
+
+                       if (p->l.t.t != BC_LEX_RBRACKET) {
+                               s = BC_STATUS_PARSE_BAD_FUNC;
+                               goto err;
+                       }
+
+                       s = bc_lex_next(&p->l);
+                       if (s) goto err;
+               }
+
+               comma = p->l.t.t == BC_LEX_COMMA;
+               if (comma) {
+                       s = bc_lex_next(&p->l);
+                       if (s) goto err;
+               }
+
+               s = bc_func_insert(p->func, name, var);
+               if (s) goto err;
+       }
+
+       if (comma) return BC_STATUS_PARSE_BAD_FUNC;
+       if (!one) return BC_STATUS_PARSE_NO_AUTO;
+
+       if (p->l.t.t != BC_LEX_NLINE && p->l.t.t != BC_LEX_SCOLON)
+               return BC_STATUS_PARSE_BAD_TOKEN;
+
+       return bc_lex_next(&p->l);
+
+err:
+       free(name);
+       return s;
+}
+
+static BcStatus bc_parse_body(BcParse *p, bool brace)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       uint8_t *flag_ptr = bc_vec_top(&p->flags);
+
+       *flag_ptr &= ~(BC_PARSE_FLAG_BODY);
+
+       if (*flag_ptr & BC_PARSE_FLAG_FUNC_INNER) {
+
+               if (!brace) return BC_STATUS_PARSE_BAD_TOKEN;
+               p->auto_part = p->l.t.t != BC_LEX_KEY_AUTO;
+
+               if (!p->auto_part) {
+                       s = bc_parse_auto(p);
+                       if (s) return s;
+               }
+
+               if (p->l.t.t == BC_LEX_NLINE) s = bc_lex_next(&p->l);
+       }
+       else {
+               s = bc_parse_stmt(p);
+               if (!s && !brace) s = bc_parse_endBody(p, false);
+       }
+
+       return s;
+}
+
+static BcStatus bc_parse_stmt(BcParse *p)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+
+       switch (p->l.t.t) {
+
+               case BC_LEX_NLINE:
+               {
+                       return bc_lex_next(&p->l);
+               }
+
+               case BC_LEX_KEY_ELSE:
+               {
+                       p->auto_part = false;
+                       break;
+               }
+
+               case BC_LEX_LBRACE:
+               {
+                       if (!BC_PARSE_BODY(p)) return BC_STATUS_PARSE_BAD_TOKEN;
+
+                       ++p->nbraces;
+                       s = bc_lex_next(&p->l);
+                       if (s) return s;
+
+                       return bc_parse_body(p, true);
+               }
+
+               case BC_LEX_KEY_AUTO:
+               {
+                       return bc_parse_auto(p);
+               }
+
+               default:
+               {
+                       p->auto_part = false;
+
+                       if (BC_PARSE_IF_END(p)) {
+                               bc_parse_noElse(p);
+                               return BC_STATUS_SUCCESS;
+                       }
+                       else if (BC_PARSE_BODY(p))
+                               return bc_parse_body(p, false);
+
+                       break;
+               }
+       }
+
+       switch (p->l.t.t) {
+
+               case BC_LEX_OP_INC:
+               case BC_LEX_OP_DEC:
+               case BC_LEX_OP_MINUS:
+               case BC_LEX_OP_BOOL_NOT:
+               case BC_LEX_LPAREN:
+               case BC_LEX_NAME:
+               case BC_LEX_NUMBER:
+               case BC_LEX_KEY_IBASE:
+               case BC_LEX_KEY_LAST:
+               case BC_LEX_KEY_LENGTH:
+               case BC_LEX_KEY_OBASE:
+               case BC_LEX_KEY_READ:
+               case BC_LEX_KEY_SCALE:
+               case BC_LEX_KEY_SQRT:
+               {
+                       s = bc_parse_expr(p, BC_PARSE_PRINT, bc_parse_next_expr);
+                       break;
+               }
+
+               case BC_LEX_KEY_ELSE:
+               {
+                       s = bc_parse_else(p);
+                       break;
+               }
+
+               case BC_LEX_SCOLON:
+               {
+                       while (!s && p->l.t.t == BC_LEX_SCOLON) s = bc_lex_next(&p->l);
+                       break;
+               }
+
+               case BC_LEX_RBRACE:
+               {
+                       s = bc_parse_endBody(p, true);
+                       break;
+               }
+
+               case BC_LEX_STR:
+               {
+                       s = bc_parse_string(p, BC_INST_PRINT_STR);
+                       break;
+               }
+
+               case BC_LEX_KEY_BREAK:
+               case BC_LEX_KEY_CONTINUE:
+               {
+                       s = bc_parse_loopExit(p, p->l.t.t);
+                       break;
+               }
+
+               case BC_LEX_KEY_FOR:
+               {
+                       s = bc_parse_for(p);
+                       break;
+               }
+
+               case BC_LEX_KEY_HALT:
+               {
+                       bc_parse_push(p, BC_INST_HALT);
+                       s = bc_lex_next(&p->l);
+                       break;
+               }
+
+               case BC_LEX_KEY_IF:
+               {
+                       s = bc_parse_if(p);
+                       break;
+               }
+
+               case BC_LEX_KEY_LIMITS:
+               {
+                       s = bc_lex_next(&p->l);
+                       if (s) return s;
+                       s = BC_STATUS_LIMITS;
+                       break;
+               }
+
+               case BC_LEX_KEY_PRINT:
+               {
+                       s = bc_parse_print(p);
+                       break;
+               }
+
+               case BC_LEX_KEY_QUIT:
+               {
+                       // Quit is a compile-time command. We don't exit directly,
+                       // so the vm can clean up. Limits do the same thing.
+                       s = BC_STATUS_QUIT;
+                       break;
+               }
+
+               case BC_LEX_KEY_RETURN:
+               {
+                       s = bc_parse_return(p);
+                       break;
+               }
+
+               case BC_LEX_KEY_WHILE:
+               {
+                       s = bc_parse_while(p);
+                       break;
+               }
+
+               default:
+               {
+                       s = BC_STATUS_PARSE_BAD_TOKEN;
+                       break;
+               }
+       }
+
+       return s;
+}
+
+static BcStatus bc_parse_parse(BcParse *p)
+{
+       BcStatus s;
+
+       if (p->l.t.t == BC_LEX_EOF)
+               s = p->flags.len > 0 ? BC_STATUS_PARSE_NO_BLOCK_END : BC_STATUS_LEX_EOF;
+       else if (p->l.t.t == BC_LEX_KEY_DEFINE) {
+               if (!BC_PARSE_CAN_EXEC(p)) return BC_STATUS_PARSE_BAD_TOKEN;
+               s = bc_parse_func(p);
+       }
+       else
+               s = bc_parse_stmt(p);
+
+       if ((s && s != BC_STATUS_QUIT && s != BC_STATUS_LIMITS) || bcg.signe)
+               s = bc_parse_reset(p, s);
+
+       return s;
+}
+
+static BcStatus bc_parse_expr(BcParse *p, uint8_t flags, BcParseNext next)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       BcInst prev = BC_INST_PRINT;
+       BcLexType top, t = p->l.t.t;
+       size_t nexprs = 0, ops_bgn = p->ops.len;
+       uint32_t i, nparens, nrelops;
+       bool paren_first, paren_expr, rprn, done, get_token, assign, bin_last;
+
+       paren_first = p->l.t.t == BC_LEX_LPAREN;
+       nparens = nrelops = 0;
+       paren_expr = rprn = done = get_token = assign = false;
+       bin_last = true;
+
+       for (; !bcg.signe && !s && !done && bc_parse_exprs[t]; t = p->l.t.t) {
+               switch (t) {
+
+                       case BC_LEX_OP_INC:
+                       case BC_LEX_OP_DEC:
+                       {
+                               s = bc_parse_incdec(p, &prev, &paren_expr, &nexprs, flags);
+                               rprn = get_token = bin_last = false;
+                               break;
+                       }
+
+                       case BC_LEX_OP_MINUS:
+                       {
+                               s = bc_parse_minus(p, &prev, ops_bgn, rprn, &nexprs);
+                               rprn = get_token = false;
+                               bin_last = prev == BC_INST_MINUS;
+                               break;
+                       }
+
+                       case BC_LEX_OP_ASSIGN_POWER:
+                       case BC_LEX_OP_ASSIGN_MULTIPLY:
+                       case BC_LEX_OP_ASSIGN_DIVIDE:
+                       case BC_LEX_OP_ASSIGN_MODULUS:
+                       case BC_LEX_OP_ASSIGN_PLUS:
+                       case BC_LEX_OP_ASSIGN_MINUS:
+                       case BC_LEX_OP_ASSIGN:
+                       {
+                               if (prev != BC_INST_VAR && prev != BC_INST_ARRAY_ELEM &&
+                                   prev != BC_INST_SCALE && prev != BC_INST_IBASE &&
+                                   prev != BC_INST_OBASE && prev != BC_INST_LAST)
+                               {
+                                       s = BC_STATUS_PARSE_BAD_ASSIGN;
+                                       break;
+                               }
+                       }
+                       // Fallthrough.
+                       case BC_LEX_OP_POWER:
+                       case BC_LEX_OP_MULTIPLY:
+                       case BC_LEX_OP_DIVIDE:
+                       case BC_LEX_OP_MODULUS:
+                       case BC_LEX_OP_PLUS:
+                       case BC_LEX_OP_REL_EQ:
+                       case BC_LEX_OP_REL_LE:
+                       case BC_LEX_OP_REL_GE:
+                       case BC_LEX_OP_REL_NE:
+                       case BC_LEX_OP_REL_LT:
+                       case BC_LEX_OP_REL_GT:
+                       case BC_LEX_OP_BOOL_NOT:
+                       case BC_LEX_OP_BOOL_OR:
+                       case BC_LEX_OP_BOOL_AND:
+                       {
+                               if (((t == BC_LEX_OP_BOOL_NOT) != bin_last) ||
+                                   (t != BC_LEX_OP_BOOL_NOT && prev == BC_INST_BOOL_NOT))
+                               {
+                                       return BC_STATUS_PARSE_BAD_EXP;
+                               }
+
+                               nrelops += t >= BC_LEX_OP_REL_EQ && t <= BC_LEX_OP_REL_GT;
+                               prev = BC_PARSE_TOKEN_INST(t);
+                               s = bc_parse_operator(p, t, ops_bgn, &nexprs, true);
+                               rprn = get_token = false;
+                               bin_last = t != BC_LEX_OP_BOOL_NOT;
+
+                               break;
+                       }
+
+                       case BC_LEX_LPAREN:
+                       {
+                               if (BC_PARSE_LEAF(prev, rprn)) return BC_STATUS_PARSE_BAD_EXP;
+
+                               ++nparens;
+                               paren_expr = rprn = bin_last = false;
+                               get_token = true;
+                               bc_vec_push(&p->ops, &t);
+
+                               break;
+                       }
+
+                       case BC_LEX_RPAREN:
+                       {
+                               if (bin_last || prev == BC_INST_BOOL_NOT)
+                                       return BC_STATUS_PARSE_BAD_EXP;
+
+                               if (nparens == 0) {
+                                       s = BC_STATUS_SUCCESS;
+                                       done = true;
+                                       get_token = false;
+                                       break;
+                               }
+                               else if (!paren_expr)
+                                       return BC_STATUS_PARSE_EMPTY_EXP;
+
+                               --nparens;
+                               paren_expr = rprn = true;
+                               get_token = bin_last = false;
+
+                               s = bc_parse_rightParen(p, ops_bgn, &nexprs);
+
+                               break;
+                       }
+
+                       case BC_LEX_NAME:
+                       {
+                               if (BC_PARSE_LEAF(prev, rprn)) return BC_STATUS_PARSE_BAD_EXP;
+
+                               paren_expr = true;
+                               rprn = get_token = bin_last = false;
+                               s = bc_parse_name(p, &prev, flags & ~BC_PARSE_NOCALL);
+                               ++nexprs;
+
+                               break;
+                       }
+
+                       case BC_LEX_NUMBER:
+                       {
+                               if (BC_PARSE_LEAF(prev, rprn)) return BC_STATUS_PARSE_BAD_EXP;
+
+                               bc_parse_number(p, &prev, &nexprs);
+                               paren_expr = get_token = true;
+                               rprn = bin_last = false;
+
+                               break;
+                       }
+
+                       case BC_LEX_KEY_IBASE:
+                       case BC_LEX_KEY_LAST:
+                       case BC_LEX_KEY_OBASE:
+                       {
+                               if (BC_PARSE_LEAF(prev, rprn)) return BC_STATUS_PARSE_BAD_EXP;
+
+                               prev = (char) (t - BC_LEX_KEY_IBASE + BC_INST_IBASE);
+                               bc_parse_push(p, (char) prev);
+
+                               paren_expr = get_token = true;
+                               rprn = bin_last = false;
+                               ++nexprs;
+
+                               break;
+                       }
+
+                       case BC_LEX_KEY_LENGTH:
+                       case BC_LEX_KEY_SQRT:
+                       {
+                               if (BC_PARSE_LEAF(prev, rprn)) return BC_STATUS_PARSE_BAD_EXP;
+
+                               s = bc_parse_builtin(p, t, flags, &prev);
+                               paren_expr = true;
+                               rprn = get_token = bin_last = false;
+                               ++nexprs;
+
+                               break;
+                       }
+
+                       case BC_LEX_KEY_READ:
+                       {
+                               if (BC_PARSE_LEAF(prev, rprn))
+                                       return BC_STATUS_PARSE_BAD_EXP;
+                               else if (flags & BC_PARSE_NOREAD)
+                                       s = BC_STATUS_EXEC_REC_READ;
+                               else
+                                       s = bc_parse_read(p);
+
+                               paren_expr = true;
+                               rprn = get_token = bin_last = false;
+                               ++nexprs;
+                               prev = BC_INST_READ;
+
+                               break;
+                       }
+
+                       case BC_LEX_KEY_SCALE:
+                       {
+                               if (BC_PARSE_LEAF(prev, rprn)) return BC_STATUS_PARSE_BAD_EXP;
+
+                               s = bc_parse_scale(p, &prev, flags);
+                               paren_expr = true;
+                               rprn = get_token = bin_last = false;
+                               ++nexprs;
+                               prev = BC_INST_SCALE;
+
+                               break;
+                       }
+
+                       default:
+                       {
+                               s = BC_STATUS_PARSE_BAD_TOKEN;
+                               break;
+                       }
+               }
+
+               if (!s && get_token) s = bc_lex_next(&p->l);
+       }
+
+       if (s) return s;
+       if (bcg.signe) return BC_STATUS_EXEC_SIGNAL;
+
+       while (p->ops.len > ops_bgn) {
+
+               top = BC_PARSE_TOP_OP(p);
+               assign = top >= BC_LEX_OP_ASSIGN_POWER && top <= BC_LEX_OP_ASSIGN;
+
+               if (top == BC_LEX_LPAREN || top == BC_LEX_RPAREN)
+                       return BC_STATUS_PARSE_BAD_EXP;
+
+               bc_parse_push(p, BC_PARSE_TOKEN_INST(top));
+
+               nexprs -= top != BC_LEX_OP_BOOL_NOT && top != BC_LEX_NEG;
+               bc_vec_pop(&p->ops);
+       }
+
+       s = BC_STATUS_PARSE_BAD_EXP;
+       if (prev == BC_INST_BOOL_NOT || nexprs != 1) return s;
+
+       for (i = 0; s && i < next.len; ++i) s *= t != next.tokens[i];
+       if (s) return s;
+
+       if (!(flags & BC_PARSE_REL) && nrelops) {
+               s = bc_vm_posixError(BC_STATUS_POSIX_REL_POS, p->l.f, p->l.line, NULL);
+               if (s) return s;
+       }
+       else if ((flags & BC_PARSE_REL) && nrelops > 1) {
+               s = bc_vm_posixError(BC_STATUS_POSIX_MULTIREL, p->l.f, p->l.line, NULL);
+               if (s) return s;
+       }
+
+       if (flags & BC_PARSE_PRINT) {
+               if (paren_first || !assign) bc_parse_push(p, BC_INST_PRINT);
+               bc_parse_push(p, BC_INST_POP);
+       }
+
+       return s;
+}
+
+static void bc_parse_init(BcParse *p, BcProgram *prog, size_t func)
+{
+       bc_parse_create(p, prog, func, bc_parse_parse, bc_lex_token);
+}
+
+static BcStatus bc_parse_expression(BcParse *p, uint8_t flags)
+{
+       return bc_parse_expr(p, flags, bc_parse_next_read);
+}
+#endif // ENABLE_BC
+
+#ifdef ENABLE_DC
+static BcStatus dc_parse_register(BcParse *p)
+{
+       BcStatus s;
+       char *name;
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+       if (p->l.t.t != BC_LEX_NAME) return BC_STATUS_PARSE_BAD_TOKEN;
+
+       name = xstrdup(p->l.t.v.v);
+       bc_parse_pushName(p, name);
+
+       return s;
+}
+
+static BcStatus dc_parse_string(BcParse *p)
+{
+       char *str, *name, b[DC_PARSE_BUF_LEN + 1];
+       size_t idx, len = p->prog->strs.len;
+
+       sprintf(b, "%0*zu", DC_PARSE_BUF_LEN, len);
+       name = xstrdup(b);
+
+       str = xstrdup(p->l.t.v.v);
+       bc_parse_push(p, BC_INST_STR);
+       bc_parse_pushIndex(p, len);
+       bc_vec_push(&p->prog->strs, &str);
+       bc_parse_addFunc(p, name, &idx);
+
+       return bc_lex_next(&p->l);
+}
+
+static BcStatus dc_parse_mem(BcParse *p, uint8_t inst, bool name, bool store)
+{
+       BcStatus s;
+
+       bc_parse_push(p, inst);
+       if (name) {
+               s = dc_parse_register(p);
+               if (s) return s;
+       }
+
+       if (store) {
+               bc_parse_push(p, BC_INST_SWAP);
+               bc_parse_push(p, BC_INST_ASSIGN);
+               bc_parse_push(p, BC_INST_POP);
+       }
+
+       return bc_lex_next(&p->l);
+}
+
+static BcStatus dc_parse_cond(BcParse *p, uint8_t inst)
+{
+       BcStatus s;
+
+       bc_parse_push(p, inst);
+       bc_parse_push(p, BC_INST_EXEC_COND);
+
+       s = dc_parse_register(p);
+       if (s) return s;
+
+       s = bc_lex_next(&p->l);
+       if (s) return s;
+
+       if (p->l.t.t == BC_LEX_ELSE) {
+               s = dc_parse_register(p);
+               if (s) return s;
+               s = bc_lex_next(&p->l);
+       }
+       else
+               bc_parse_push(p, BC_PARSE_STREND);
+
+       return s;
+}
+
+static BcStatus dc_parse_token(BcParse *p, BcLexType t, uint8_t flags)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       BcInst prev;
+       uint8_t inst;
+       bool assign, get_token = false;
+
+       switch (t) {
+
+               case BC_LEX_OP_REL_EQ:
+               case BC_LEX_OP_REL_LE:
+               case BC_LEX_OP_REL_GE:
+               case BC_LEX_OP_REL_NE:
+               case BC_LEX_OP_REL_LT:
+               case BC_LEX_OP_REL_GT:
+               {
+                       s = dc_parse_cond(p, t - BC_LEX_OP_REL_EQ + BC_INST_REL_EQ);
+                       break;
+               }
+
+               case BC_LEX_SCOLON:
+               case BC_LEX_COLON:
+               {
+                       s = dc_parse_mem(p, BC_INST_ARRAY_ELEM, true, t == BC_LEX_COLON);
+                       break;
+               }
+
+               case BC_LEX_STR:
+               {
+                       s = dc_parse_string(p);
+                       break;
+               }
+
+               case BC_LEX_NEG:
+               case BC_LEX_NUMBER:
+               {
+                       if (t == BC_LEX_NEG) {
+                               s = bc_lex_next(&p->l);
+                               if (s) return s;
+                               if (p->l.t.t != BC_LEX_NUMBER) return BC_STATUS_PARSE_BAD_TOKEN;
+                       }
+
+                       bc_parse_number(p, &prev, &p->nbraces);
+
+                       if (t == BC_LEX_NEG) bc_parse_push(p, BC_INST_NEG);
+                       get_token = true;
+
+                       break;
+               }
+
+               case BC_LEX_KEY_READ:
+               {
+                       if (flags & BC_PARSE_NOREAD)
+                               s = BC_STATUS_EXEC_REC_READ;
+                       else
+                               bc_parse_push(p, BC_INST_READ);
+                       get_token = true;
+                       break;
+               }
+
+               case BC_LEX_OP_ASSIGN:
+               case BC_LEX_STORE_PUSH:
+               {
+                       assign = t == BC_LEX_OP_ASSIGN;
+                       inst = assign ? BC_INST_VAR : BC_INST_PUSH_TO_VAR;
+                       s = dc_parse_mem(p, inst, true, assign);
+                       break;
+               }
+
+               case BC_LEX_LOAD:
+               case BC_LEX_LOAD_POP:
+               {
+                       inst = t == BC_LEX_LOAD_POP ? BC_INST_PUSH_VAR : BC_INST_LOAD;
+                       s = dc_parse_mem(p, inst, true, false);
+                       break;
+               }
+
+               case BC_LEX_STORE_IBASE:
+               case BC_LEX_STORE_SCALE:
+               case BC_LEX_STORE_OBASE:
+               {
+                       inst = t - BC_LEX_STORE_IBASE + BC_INST_IBASE;
+                       s = dc_parse_mem(p, inst, false, true);
+                       break;
+               }
+
+               default:
+               {
+                       s = BC_STATUS_PARSE_BAD_TOKEN;
+                       get_token = true;
+                       break;
+               }
+       }
+
+       if (!s && get_token) s = bc_lex_next(&p->l);
+
+       return s;
+}
+
+static BcStatus dc_parse_expr(BcParse *p, uint8_t flags)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       BcInst inst;
+       BcLexType t;
+
+       if (flags & BC_PARSE_NOCALL) p->nbraces = p->prog->results.len;
+
+       for (t = p->l.t.t; !s && t != BC_LEX_EOF; t = p->l.t.t) {
+
+               inst = dc_parse_insts[t];
+
+               if (inst != BC_INST_INVALID) {
+                       bc_parse_push(p, inst);
+                       s = bc_lex_next(&p->l);
+               }
+               else
+                       s = dc_parse_token(p, t, flags);
+       }
+
+       if (!s && p->l.t.t == BC_LEX_EOF && (flags & BC_PARSE_NOCALL))
+               bc_parse_push(p, BC_INST_POP_EXEC);
+
+       return s;
+}
+
+static BcStatus dc_parse_parse(BcParse *p)
+{
+       BcStatus s;
+
+       if (p->l.t.t == BC_LEX_EOF)
+               s = BC_STATUS_LEX_EOF;
+       else
+               s = dc_parse_expr(p, 0);
+
+       if (s || bcg.signe) s = bc_parse_reset(p, s);
+
+       return s;
+}
+
+static void dc_parse_init(BcParse *p, BcProgram *prog, size_t func)
+{
+       bc_parse_create(p, prog, func, dc_parse_parse, dc_lex_token);
+}
+#endif // ENABLE_DC
+
+static void bc_program_search(BcProgram *p, char *id, BcVec **ret, bool var)
+{
+       BcStatus s;
+       BcId e, *ptr;
+       BcVec *v, *map;
+       size_t i;
+       BcResultData data;
+       bool new;
+
+       v = var ? &p->vars : &p->arrs;
+       map = var ? &p->var_map : &p->arr_map;
+
+       e.name = id;
+       e.idx = v->len;
+       s = bc_map_insert(map, &e, &i);
+       new = s != BC_STATUS_VEC_ITEM_EXISTS;
+
+       if (new) {
+               bc_array_init(&data.v, var);
+               bc_vec_push(v, &data.v);
+       }
+
+       ptr = bc_vec_item(map, i);
+       if (new) ptr->name = xstrdup(e.name);
+       *ret = bc_vec_item(v, ptr->idx);
+}
+
+static BcStatus bc_program_num(BcProgram *p, BcResult *r, BcNum **num, bool hex)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+
+       switch (r->t) {
+
+               case BC_RESULT_STR:
+               case BC_RESULT_TEMP:
+               case BC_RESULT_IBASE:
+               case BC_RESULT_SCALE:
+               case BC_RESULT_OBASE:
+               {
+                       *num = &r->d.n;
+                       break;
+               }
+
+               case BC_RESULT_CONSTANT:
+               {
+                       char **str = bc_vec_item(&p->consts, r->d.id.idx);
+                       size_t base_t, len = strlen(*str);
+                       BcNum *base;
+
+                       bc_num_init(&r->d.n, len);
+
+                       hex = hex && len == 1;
+                       base = hex ? &p->hexb : &p->ib;
+                       base_t = hex ? BC_NUM_MAX_IBASE : p->ib_t;
+                       s = bc_num_parse(&r->d.n, *str, base, base_t);
+
+                       if (s) {
+                               bc_num_free(&r->d.n);
+                               return s;
+                       }
+
+                       *num = &r->d.n;
+                       r->t = BC_RESULT_TEMP;
+
+                       break;
+               }
+
+               case BC_RESULT_VAR:
+               case BC_RESULT_ARRAY:
+               case BC_RESULT_ARRAY_ELEM:
+               {
+                       BcVec *v;
+
+                       bc_program_search(p, r->d.id.name, &v, r->t == BC_RESULT_VAR);
+
+                       if (r->t == BC_RESULT_ARRAY_ELEM) {
+                               v = bc_vec_top(v);
+                               if (v->len <= r->d.id.idx) bc_array_expand(v, r->d.id.idx + 1);
+                               *num = bc_vec_item(v, r->d.id.idx);
+                       }
+                       else
+                               *num = bc_vec_top(v);
+
+                       break;
+               }
+
+               case BC_RESULT_LAST:
+               {
+                       *num = &p->last;
+                       break;
+               }
+
+               case BC_RESULT_ONE:
+               {
+                       *num = &p->one;
+                       break;
+               }
+       }
+
+       return s;
+}
+
+static BcStatus bc_program_binOpPrep(BcProgram *p, BcResult **l, BcNum **ln,
+                                     BcResult **r, BcNum **rn, bool assign)
+{
+       BcStatus s;
+       bool hex;
+       BcResultType lt, rt;
+
+       if (!BC_PROG_STACK(&p->results, 2)) return BC_STATUS_EXEC_STACK;
+
+       *r = bc_vec_item_rev(&p->results, 0);
+       *l = bc_vec_item_rev(&p->results, 1);
+
+       lt = (*l)->t;
+       rt = (*r)->t;
+       hex = assign && (lt == BC_RESULT_IBASE || lt == BC_RESULT_OBASE);
+
+       s = bc_program_num(p, *l, ln, false);
+       if (s) return s;
+       s = bc_program_num(p, *r, rn, hex);
+       if (s) return s;
+
+       // We run this again under these conditions in case any vector has been
+       // reallocated out from under the BcNums or arrays we had.
+       if (lt == rt && (lt == BC_RESULT_VAR || lt == BC_RESULT_ARRAY_ELEM)) {
+               s = bc_program_num(p, *l, ln, false);
+               if (s) return s;
+       }
+
+       if (!BC_PROG_NUM((*l), (*ln)) && (!assign || (*l)->t != BC_RESULT_VAR))
+               return BC_STATUS_EXEC_BAD_TYPE;
+       if (!assign && !BC_PROG_NUM((*r), (*ln))) return BC_STATUS_EXEC_BAD_TYPE;
+
+#ifdef ENABLE_DC
+#else // ENABLE_DC
+#endif // ENABLE_DC
+
+       return s;
+}
+
+static void bc_program_binOpRetire(BcProgram *p, BcResult *r)
+{
+       r->t = BC_RESULT_TEMP;
+       bc_vec_pop(&p->results);
+       bc_vec_pop(&p->results);
+       bc_vec_push(&p->results, r);
+}
+
+static BcStatus bc_program_prep(BcProgram *p, BcResult **r, BcNum **n)
+{
+       BcStatus s;
+
+       if (!BC_PROG_STACK(&p->results, 1)) return BC_STATUS_EXEC_STACK;
+       *r = bc_vec_top(&p->results);
+
+       s = bc_program_num(p, *r, n, false);
+       if (s) return s;
+
+#ifdef ENABLE_DC
+#endif // ENABLE_DC
+
+       if (!BC_PROG_NUM((*r), (*n))) return BC_STATUS_EXEC_BAD_TYPE;
+
+       return s;
+}
+
+static void bc_program_retire(BcProgram *p, BcResult *r, BcResultType t)
+{
+       r->t = t;
+       bc_vec_pop(&p->results);
+       bc_vec_push(&p->results, r);
+}
+
+static BcStatus bc_program_op(BcProgram *p, char inst)
+{
+       BcStatus s;
+       BcResult *opd1, *opd2, res;
+       BcNum *n1, *n2 = NULL;
+
+       s = bc_program_binOpPrep(p, &opd1, &n1, &opd2, &n2, false);
+       if (s) return s;
+       bc_num_init(&res.d.n, BC_NUM_DEF_SIZE);
+
+       s = bc_program_ops[inst - BC_INST_POWER](n1, n2, &res.d.n, p->scale);
+       if (s) goto err;
+       bc_program_binOpRetire(p, &res);
+
+       return s;
+
+err:
+       bc_num_free(&res.d.n);
+       return s;
+}
+
+static BcStatus bc_program_read(BcProgram *p)
+{
+       BcStatus s;
+       BcParse parse;
+       BcVec buf;
+       BcInstPtr ip;
+       size_t i;
+       BcFunc *f = bc_vec_item(&p->fns, BC_PROG_READ);
+
+       for (i = 0; i < p->stack.len; ++i) {
+               BcInstPtr *ip_ptr = bc_vec_item(&p->stack, i);
+               if (ip_ptr->func == BC_PROG_READ) return BC_STATUS_EXEC_REC_READ;
+       }
+
+       bc_vec_npop(&f->code, f->code.len);
+       bc_vec_init(&buf, sizeof(char), NULL);
+
+       s = bc_read_line(&buf, "read> ");
+       if (s) goto io_err;
+
+       p->parse_init(&parse, p, BC_PROG_READ);
+       bc_lex_file(&parse.l, bc_program_stdin_name);
+
+       s = bc_parse_text(&parse, buf.v);
+       if (s) goto exec_err;
+       s = p->parse_expr(&parse, BC_PARSE_NOREAD);
+       if (s) goto exec_err;
+
+       if (parse.l.t.t != BC_LEX_NLINE && parse.l.t.t != BC_LEX_EOF) {
+               s = BC_STATUS_EXEC_BAD_READ_EXPR;
+               goto exec_err;
+       }
+
+       ip.func = BC_PROG_READ;
+       ip.idx = 0;
+       ip.len = p->results.len;
+
+       // Update this pointer, just in case.
+       f = bc_vec_item(&p->fns, BC_PROG_READ);
+
+       bc_vec_pushByte(&f->code, BC_INST_POP_EXEC);
+       bc_vec_push(&p->stack, &ip);
+
+exec_err:
+       bc_parse_free(&parse);
+io_err:
+       bc_vec_free(&buf);
+       return s;
+}
+
+static size_t bc_program_index(char *code, size_t *bgn)
+{
+       char amt = code[(*bgn)++], i = 0;
+       size_t res = 0;
+
+       for (; i < amt; ++i, ++(*bgn))
+               res |= (((size_t)((int) code[*bgn]) & UCHAR_MAX) << (i * CHAR_BIT));
+
+       return res;
+}
+
+static char *bc_program_name(char *code, size_t *bgn)
+{
+       size_t i;
+       char c, *s, *str = code + *bgn, *ptr = strchr(str, BC_PARSE_STREND);
+
+       s = xmalloc(ptr - str + 1);
+       c = code[(*bgn)++];
+
+       for (i = 0; c != 0 && c != BC_PARSE_STREND; c = code[(*bgn)++], ++i)
+               s[i] = c;
+
+       s[i] = '\0';
+
+       return s;
+}
+
+static void bc_program_printString(const char *str, size_t *nchars)
+{
+       size_t i, len = strlen(str);
+
+#ifdef ENABLE_DC
+       if (len == 0) {
+               bc_vm_putchar('\0');
+               return;
+       }
+#endif // ENABLE_DC
+
+       for (i = 0; i < len; ++i, ++(*nchars)) {
+
+               int c = str[i];
+
+               if (c != '\\' || i == len - 1)
+                       bc_vm_putchar(c);
+               else {
+
+                       c = str[++i];
+
+                       switch (c) {
+
+                               case 'a':
+                               {
+                                       bc_vm_putchar('\a');
+                                       break;
+                               }
+
+                               case 'b':
+                               {
+                                       bc_vm_putchar('\b');
+                                       break;
+                               }
+
+                               case '\\':
+                               case 'e':
+                               {
+                                       bc_vm_putchar('\\');
+                                       break;
+                               }
+
+                               case 'f':
+                               {
+                                       bc_vm_putchar('\f');
+                                       break;
+                               }
+
+                               case 'n':
+                               {
+                                       bc_vm_putchar('\n');
+                                       *nchars = SIZE_MAX;
+                                       break;
+                               }
+
+                               case 'r':
+                               {
+                                       bc_vm_putchar('\r');
+                                       break;
+                               }
+
+                               case 'q':
+                               {
+                                       bc_vm_putchar('"');
+                                       break;
+                               }
+
+                               case 't':
+                               {
+                                       bc_vm_putchar('\t');
+                                       break;
+                               }
+
+                               default:
+                               {
+                                       // Just print the backslash and following character.
+                                       bc_vm_putchar('\\');
+                                       ++(*nchars);
+                                       bc_vm_putchar(c);
+                                       break;
+                               }
+                       }
+               }
+       }
+}
+
+static BcStatus bc_program_print(BcProgram *p, char inst, size_t idx)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       BcResult *r;
+       size_t len, i;
+       char *str;
+       BcNum *num = NULL;
+       bool pop = inst != BC_INST_PRINT;
+
+       if (!BC_PROG_STACK(&p->results, idx + 1)) return BC_STATUS_EXEC_STACK;
+
+       r = bc_vec_item_rev(&p->results, idx);
+       s = bc_program_num(p, r, &num, false);
+       if (s) return s;
+
+       if (BC_PROG_NUM(r, num)) {
+               s = bc_num_print(num, &p->ob, p->ob_t, !pop, &p->nchars, p->len);
+               if (!s) bc_num_copy(&p->last, num);
+       }
+       else {
+
+               idx = (r->t == BC_RESULT_STR) ? r->d.id.idx : num->rdx;
+               str = *((char **) bc_vec_item(&p->strs, idx));
+
+               if (inst == BC_INST_PRINT_STR) {
+                       for (i = 0, len = strlen(str); i < len; ++i) {
+                               char c = str[i];
+                               bc_vm_putchar(c);
+                               if (c == '\n') p->nchars = SIZE_MAX;
+                               ++p->nchars;
+                       }
+               }
+               else {
+                       bc_program_printString(str, &p->nchars);
+                       if (inst == BC_INST_PRINT) bc_vm_putchar('\n');
+               }
+       }
+
+       if (!s && pop) bc_vec_pop(&p->results);
+
+       return s;
+}
+
+static BcStatus bc_program_negate(BcProgram *p)
+{
+       BcStatus s;
+       BcResult res, *ptr;
+       BcNum *num = NULL;
+
+       s = bc_program_prep(p, &ptr, &num);
+       if (s) return s;
+
+       bc_num_init(&res.d.n, num->len);
+       bc_num_copy(&res.d.n, num);
+       if (res.d.n.len) res.d.n.neg = !res.d.n.neg;
+
+       bc_program_retire(p, &res, BC_RESULT_TEMP);
+
+       return s;
+}
+
+static BcStatus bc_program_logical(BcProgram *p, char inst)
+{
+       BcStatus s;
+       BcResult *opd1, *opd2, res;
+       BcNum *n1, *n2;
+       bool cond = 0;
+       ssize_t cmp;
+
+       s = bc_program_binOpPrep(p, &opd1, &n1, &opd2, &n2, false);
+       if (s) return s;
+       bc_num_init(&res.d.n, BC_NUM_DEF_SIZE);
+
+       if (inst == BC_INST_BOOL_AND)
+               cond = bc_num_cmp(n1, &p->zero) && bc_num_cmp(n2, &p->zero);
+       else if (inst == BC_INST_BOOL_OR)
+               cond = bc_num_cmp(n1, &p->zero) || bc_num_cmp(n2, &p->zero);
+       else {
+
+               cmp = bc_num_cmp(n1, n2);
+
+               switch (inst) {
+
+                       case BC_INST_REL_EQ:
+                       {
+                               cond = cmp == 0;
+                               break;
+                       }
+
+                       case BC_INST_REL_LE:
+                       {
+                               cond = cmp <= 0;
+                               break;
+                       }
+
+                       case BC_INST_REL_GE:
+                       {
+                               cond = cmp >= 0;
+                               break;
+                       }
+
+                       case BC_INST_REL_NE:
+                       {
+                               cond = cmp != 0;
+                               break;
+                       }
+
+                       case BC_INST_REL_LT:
+                       {
+                               cond = cmp < 0;
+                               break;
+                       }
+
+                       case BC_INST_REL_GT:
+                       {
+                               cond = cmp > 0;
+                               break;
+                       }
+               }
+       }
+
+       (cond ? bc_num_one : bc_num_zero)(&res.d.n);
+
+       bc_program_binOpRetire(p, &res);
+
+       return s;
+}
+
+#ifdef ENABLE_DC
+static BcStatus bc_program_assignStr(BcProgram *p, BcResult *r, BcVec *v,
+                                     bool push)
+{
+       BcNum n2;
+       BcResult res;
+
+       memset(&n2, 0, sizeof(BcNum));
+       n2.rdx = res.d.id.idx = r->d.id.idx;
+       res.t = BC_RESULT_STR;
+
+       if (!push) {
+               if (!BC_PROG_STACK(&p->results, 2)) return BC_STATUS_EXEC_STACK;
+               bc_vec_pop(v);
+               bc_vec_pop(&p->results);
+       }
+
+       bc_vec_pop(&p->results);
+
+       bc_vec_push(&p->results, &res);
+       bc_vec_push(v, &n2);
+
+       return BC_STATUS_SUCCESS;
+}
+#endif // ENABLE_DC
+
+static BcStatus bc_program_copyToVar(BcProgram *p, char *name, bool var)
+{
+       BcStatus s;
+       BcResult *ptr, r;
+       BcVec *v;
+       BcNum *n;
+
+       if (!BC_PROG_STACK(&p->results, 1)) return BC_STATUS_EXEC_STACK;
+
+       ptr = bc_vec_top(&p->results);
+       if ((ptr->t == BC_RESULT_ARRAY) != !var) return BC_STATUS_EXEC_BAD_TYPE;
+       bc_program_search(p, name, &v, var);
+
+#ifdef ENABLE_DC
+       if (ptr->t == BC_RESULT_STR && !var) return BC_STATUS_EXEC_BAD_TYPE;
+       if (ptr->t == BC_RESULT_STR) return bc_program_assignStr(p, ptr, v, true);
+#endif // ENABLE_DC
+
+       s = bc_program_num(p, ptr, &n, false);
+       if (s) return s;
+
+       // Do this once more to make sure that pointers were not invalidated.
+       bc_program_search(p, name, &v, var);
+
+       if (var) {
+               bc_num_init(&r.d.n, BC_NUM_DEF_SIZE);
+               bc_num_copy(&r.d.n, n);
+       }
+       else {
+               bc_array_init(&r.d.v, true);
+               bc_array_copy(&r.d.v, (BcVec *) n);
+       }
+
+       bc_vec_push(v, &r.d);
+       bc_vec_pop(&p->results);
+
+       return s;
+}
+
+static BcStatus bc_program_assign(BcProgram *p, char inst)
+{
+       BcStatus s;
+       BcResult *left, *right, res;
+       BcNum *l = NULL, *r = NULL;
+       unsigned long val, max;
+       bool assign = inst == BC_INST_ASSIGN, ib, sc;
+
+       s = bc_program_binOpPrep(p, &left, &l, &right, &r, assign);
+       if (s) return s;
+
+       ib = left->t == BC_RESULT_IBASE;
+       sc = left->t == BC_RESULT_SCALE;
+
+#ifdef ENABLE_DC
+
+       if (right->t == BC_RESULT_STR) {
+
+               BcVec *v;
+
+               if (left->t != BC_RESULT_VAR) return BC_STATUS_EXEC_BAD_TYPE;
+               bc_program_search(p, left->d.id.name, &v, true);
+
+               return bc_program_assignStr(p, right, v, false);
+       }
+#endif // ENABLE_DC
+
+       if (left->t == BC_RESULT_CONSTANT || left->t == BC_RESULT_TEMP)
+               return BC_STATUS_PARSE_BAD_ASSIGN;
+
+#ifdef ENABLE_BC
+       if (inst == BC_INST_ASSIGN_DIVIDE && !bc_num_cmp(r, &p->zero))
+               return BC_STATUS_MATH_DIVIDE_BY_ZERO;
+
+       if (assign)
+               bc_num_copy(l, r);
+       else
+               s = bc_program_ops[inst - BC_INST_ASSIGN_POWER](l, r, l, p->scale);
+
+       if (s) return s;
+#else // ENABLE_BC
+       bc_num_copy(l, r);
+#endif // ENABLE_BC
+
+       if (ib || sc || left->t == BC_RESULT_OBASE) {
+
+               size_t *ptr;
+
+               s = bc_num_ulong(l, &val);
+               if (s) return s;
+               s = left->t - BC_RESULT_IBASE + BC_STATUS_EXEC_BAD_IBASE;
+
+               if (sc) {
+                       max = BC_MAX_SCALE;
+                       ptr = &p->scale;
+               }
+               else {
+                       if (val < BC_NUM_MIN_BASE) return s;
+                       max = ib ? BC_NUM_MAX_IBASE : BC_MAX_OBASE;
+                       ptr = ib ? &p->ib_t : &p->ob_t;
+               }
+
+               if (val > max) return s;
+               if (!sc) bc_num_copy(ib ? &p->ib : &p->ob, l);
+
+               *ptr = (size_t) val;
+               s = BC_STATUS_SUCCESS;
+       }
+
+       bc_num_init(&res.d.n, l->len);
+       bc_num_copy(&res.d.n, l);
+       bc_program_binOpRetire(p, &res);
+
+       return s;
+}
+
+static BcStatus bc_program_pushVar(BcProgram *p, char *code, size_t *bgn,
+                                   bool pop, bool copy)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       BcResult r;
+       char *name = bc_program_name(code, bgn);
+#ifdef ENABLE_DC // Exclude
+       BcNum *num;
+       BcVec *v;
+#else // ENABLE_DC
+       (void) pop, (void) copy;
+#endif // ENABLE_DC Exclude
+
+       r.t = BC_RESULT_VAR;
+       r.d.id.name = name;
+
+#ifdef ENABLE_DC
+       bc_program_search(p, name, &v, true);
+       num = bc_vec_top(v);
+
+       if (pop || copy) {
+
+               if (!BC_PROG_STACK(v, 2 - copy)) {
+                       free(name);
+                       return BC_STATUS_EXEC_STACK;
+               }
+
+               free(name);
+               name = NULL;
+
+               if (!BC_PROG_STR(num)) {
+
+                       r.t = BC_RESULT_TEMP;
+
+                       bc_num_init(&r.d.n, BC_NUM_DEF_SIZE);
+                       bc_num_copy(&r.d.n, num);
+               }
+               else {
+                       r.t = BC_RESULT_STR;
+                       r.d.id.idx = num->rdx;
+               }
+
+               if (!copy) bc_vec_pop(v);
+       }
+#endif // ENABLE_DC
+
+       bc_vec_push(&p->results, &r);
+
+       return s;
+}
+
+static BcStatus bc_program_pushArray(BcProgram *p, char *code, size_t *bgn,
+                                     char inst)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       BcResult r;
+       BcNum *num;
+
+       r.d.id.name = bc_program_name(code, bgn);
+
+       if (inst == BC_INST_ARRAY) {
+               r.t = BC_RESULT_ARRAY;
+               bc_vec_push(&p->results, &r);
+       }
+       else {
+
+               BcResult *operand;
+               unsigned long temp;
+
+               s = bc_program_prep(p, &operand, &num);
+               if (s) goto err;
+               s = bc_num_ulong(num, &temp);
+               if (s) goto err;
+
+               if (temp > BC_MAX_DIM) {
+                       s = BC_STATUS_EXEC_ARRAY_LEN;
+                       goto err;
+               }
+
+               r.d.id.idx = (size_t) temp;
+               bc_program_retire(p, &r, BC_RESULT_ARRAY_ELEM);
+       }
+
+err:
+       if (s) free(r.d.id.name);
+       return s;
+}
+
+#ifdef ENABLE_BC
+static BcStatus bc_program_incdec(BcProgram *p, char inst)
+{
+       BcStatus s;
+       BcResult *ptr, res, copy;
+       BcNum *num = NULL;
+       char inst2 = inst;
+
+       s = bc_program_prep(p, &ptr, &num);
+       if (s) return s;
+
+       if (inst == BC_INST_INC_POST || inst == BC_INST_DEC_POST) {
+               copy.t = BC_RESULT_TEMP;
+               bc_num_init(&copy.d.n, num->len);
+               bc_num_copy(&copy.d.n, num);
+       }
+
+       res.t = BC_RESULT_ONE;
+       inst = inst == BC_INST_INC_PRE || inst == BC_INST_INC_POST ?
+                  BC_INST_ASSIGN_PLUS :
+                  BC_INST_ASSIGN_MINUS;
+
+       bc_vec_push(&p->results, &res);
+       bc_program_assign(p, inst);
+
+       if (inst2 == BC_INST_INC_POST || inst2 == BC_INST_DEC_POST) {
+               bc_vec_pop(&p->results);
+               bc_vec_push(&p->results, &copy);
+       }
+
+       return s;
+}
+
+static BcStatus bc_program_call(BcProgram *p, char *code, size_t *idx)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       BcInstPtr ip;
+       size_t i, nparams = bc_program_index(code, idx);
+       BcFunc *func;
+       BcVec *v;
+       BcId *a;
+       BcResultData param;
+       BcResult *arg;
+
+       ip.idx = 0;
+       ip.func = bc_program_index(code, idx);
+       func = bc_vec_item(&p->fns, ip.func);
+
+       if (func->code.len == 0) return BC_STATUS_EXEC_UNDEFINED_FUNC;
+       if (nparams != func->nparams) return BC_STATUS_EXEC_MISMATCHED_PARAMS;
+       ip.len = p->results.len - nparams;
+
+       for (i = 0; i < nparams; ++i) {
+
+               a = bc_vec_item(&func->autos, nparams - 1 - i);
+               arg = bc_vec_top(&p->results);
+
+               if ((!a->idx) != (arg->t == BC_RESULT_ARRAY) || arg->t == BC_RESULT_STR)
+                       return BC_STATUS_EXEC_BAD_TYPE;
+
+               s = bc_program_copyToVar(p, a->name, a->idx);
+               if (s) return s;
+       }
+
+       for (; i < func->autos.len; ++i) {
+
+               a = bc_vec_item(&func->autos, i);
+               bc_program_search(p, a->name, &v, a->idx);
+
+               if (a->idx) {
+                       bc_num_init(&param.n, BC_NUM_DEF_SIZE);
+                       bc_vec_push(v, &param.n);
+               }
+               else {
+                       bc_array_init(&param.v, true);
+                       bc_vec_push(v, &param.v);
+               }
+       }
+
+       bc_vec_push(&p->stack, &ip);
+
+       return BC_STATUS_SUCCESS;
+}
+
+static BcStatus bc_program_return(BcProgram *p, char inst)
+{
+       BcStatus s;
+       BcResult res;
+       BcFunc *f;
+       size_t i;
+       BcInstPtr *ip = bc_vec_top(&p->stack);
+
+       if (!BC_PROG_STACK(&p->results, ip->len + inst == BC_INST_RET))
+               return BC_STATUS_EXEC_STACK;
+
+       f = bc_vec_item(&p->fns, ip->func);
+       res.t = BC_RESULT_TEMP;
+
+       if (inst == BC_INST_RET) {
+
+               BcNum *num;
+               BcResult *operand = bc_vec_top(&p->results);
+
+               s = bc_program_num(p, operand, &num, false);
+               if (s) return s;
+               bc_num_init(&res.d.n, num->len);
+               bc_num_copy(&res.d.n, num);
+       }
+       else {
+               bc_num_init(&res.d.n, BC_NUM_DEF_SIZE);
+               bc_num_zero(&res.d.n);
+       }
+
+       // We need to pop arguments as well, so this takes that into account.
+       for (i = 0; i < f->autos.len; ++i) {
+
+               BcVec *v;
+               BcId *a = bc_vec_item(&f->autos, i);
+
+               bc_program_search(p, a->name, &v, a->idx);
+               bc_vec_pop(v);
+       }
+
+       bc_vec_npop(&p->results, p->results.len - ip->len);
+       bc_vec_push(&p->results, &res);
+       bc_vec_pop(&p->stack);
+
+       return BC_STATUS_SUCCESS;
+}
+#endif // ENABLE_BC
+
+static unsigned long bc_program_scale(BcNum *n)
+{
+       return (unsigned long) n->rdx;
+}
+
+static unsigned long bc_program_len(BcNum *n)
+{
+       unsigned long len = n->len;
+       size_t i;
+
+       if (n->rdx != n->len) return len;
+       for (i = n->len - 1; i < n->len && n->num[i] == 0; --len, --i);
+
+       return len;
+}
+
+static BcStatus bc_program_builtin(BcProgram *p, char inst)
+{
+       BcStatus s;
+       BcResult *opnd;
+       BcNum *num = NULL;
+       BcResult res;
+       bool len = inst == BC_INST_LENGTH;
+
+       if (!BC_PROG_STACK(&p->results, 1)) return BC_STATUS_EXEC_STACK;
+       opnd = bc_vec_top(&p->results);
+
+       s = bc_program_num(p, opnd, &num, false);
+       if (s) return s;
+
+#ifdef ENABLE_DC
+       if (!BC_PROG_NUM(opnd, num) && !len) return BC_STATUS_EXEC_BAD_TYPE;
+#endif // ENABLE_DC
+
+       bc_num_init(&res.d.n, BC_NUM_DEF_SIZE);
+
+       if (inst == BC_INST_SQRT) s = bc_num_sqrt(num, &res.d.n, p->scale);
+#ifdef ENABLE_BC
+       else if (len != 0 && opnd->t == BC_RESULT_ARRAY) {
+               s = bc_num_ulong2num(&res.d.n, (unsigned long) ((BcVec *) num)->len);
+       }
+#endif // ENABLE_BC
+#ifdef ENABLE_DC
+       else if (len != 0 && !BC_PROG_NUM(opnd, num)) {
+
+               char **str;
+               size_t idx = opnd->t == BC_RESULT_STR ? opnd->d.id.idx : num->rdx;
+
+               str = bc_vec_item(&p->strs, idx);
+               s = bc_num_ulong2num(&res.d.n, strlen(*str));
+               if (s) goto err;
+       }
+#endif // ENABLE_DC
+       else {
+               BcProgramBuiltIn f = len ? bc_program_len : bc_program_scale;
+               s = bc_num_ulong2num(&res.d.n, f(num));
+               if (s) goto err;
+       }
+
+       bc_program_retire(p, &res, BC_RESULT_TEMP);
+
+       return s;
+
+err:
+       bc_num_free(&res.d.n);
+       return s;
+}
+
+#ifdef ENABLE_DC
+static BcStatus bc_program_divmod(BcProgram *p)
+{
+       BcStatus s;
+       BcResult *opd1, *opd2, res, res2;
+       BcNum *n1, *n2 = NULL;
+
+       s = bc_program_binOpPrep(p, &opd1, &n1, &opd2, &n2, false);
+       if (s) return s;
+
+       bc_num_init(&res.d.n, BC_NUM_DEF_SIZE);
+       bc_num_init(&res2.d.n, n2->len);
+
+       s = bc_num_divmod(n1, n2, &res2.d.n, &res.d.n, p->scale);
+       if (s) goto err;
+
+       bc_program_binOpRetire(p, &res2);
+       res.t = BC_RESULT_TEMP;
+       bc_vec_push(&p->results, &res);
+
+       return s;
+
+err:
+       bc_num_free(&res2.d.n);
+       bc_num_free(&res.d.n);
+       return s;
+}
+
+static BcStatus bc_program_modexp(BcProgram *p)
+{
+       BcStatus s;
+       BcResult *r1, *r2, *r3, res;
+       BcNum *n1, *n2, *n3;
+
+       if (!BC_PROG_STACK(&p->results, 3)) return BC_STATUS_EXEC_STACK;
+       s = bc_program_binOpPrep(p, &r2, &n2, &r3, &n3, false);
+       if (s) return s;
+
+       r1 = bc_vec_item_rev(&p->results, 2);
+       s = bc_program_num(p, r1, &n1, false);
+       if (s) return s;
+       if (!BC_PROG_NUM(r1, n1)) return BC_STATUS_EXEC_BAD_TYPE;
+
+       // Make sure that the values have their pointers updated, if necessary.
+       if (r1->t == BC_RESULT_VAR || r1->t == BC_RESULT_ARRAY_ELEM) {
+
+               if (r1->t == r2->t) {
+                       s = bc_program_num(p, r2, &n2, false);
+                       if (s) return s;
+               }
+
+               if (r1->t == r3->t) {
+                       s = bc_program_num(p, r3, &n3, false);
+                       if (s) return s;
+               }
+       }
+
+       bc_num_init(&res.d.n, n3->len);
+       s = bc_num_modexp(n1, n2, n3, &res.d.n);
+       if (s) goto err;
+
+       bc_vec_pop(&p->results);
+       bc_program_binOpRetire(p, &res);
+
+       return s;
+
+err:
+       bc_num_free(&res.d.n);
+       return s;
+}
+
+static BcStatus bc_program_stackLen(BcProgram *p)
+{
+       BcStatus s;
+       BcResult res;
+       size_t len = p->results.len;
+
+       res.t = BC_RESULT_TEMP;
+
+       bc_num_init(&res.d.n, BC_NUM_DEF_SIZE);
+       s = bc_num_ulong2num(&res.d.n, len);
+       if (s) goto err;
+       bc_vec_push(&p->results, &res);
+
+       return s;
+
+err:
+       bc_num_free(&res.d.n);
+       return s;
+}
+
+static BcStatus bc_program_asciify(BcProgram *p)
+{
+       BcStatus s;
+       BcResult *r, res;
+       BcNum *num = NULL, n;
+       char *str, *str2, c;
+       size_t len = p->strs.len, idx;
+       unsigned long val;
+
+       if (!BC_PROG_STACK(&p->results, 1)) return BC_STATUS_EXEC_STACK;
+       r = bc_vec_top(&p->results);
+
+       s = bc_program_num(p, r, &num, false);
+       if (s) return s;
+
+       if (BC_PROG_NUM(r, num)) {
+
+               bc_num_init(&n, BC_NUM_DEF_SIZE);
+               bc_num_copy(&n, num);
+               bc_num_truncate(&n, n.rdx);
+
+               s = bc_num_mod(&n, &p->strmb, &n, 0);
+               if (s) goto num_err;
+               s = bc_num_ulong(&n, &val);
+               if (s) goto num_err;
+
+               c = (char) val;
+
+               bc_num_free(&n);
+       }
+       else {
+               idx = (r->t == BC_RESULT_STR) ? r->d.id.idx : num->rdx;
+               str2 = *((char **) bc_vec_item(&p->strs, idx));
+               c = str2[0];
+       }
+
+       str = xmalloc(2);
+       str[0] = c;
+       str[1] = '\0';
+
+       str2 = xstrdup(str);
+       bc_program_addFunc(p, str2, &idx);
+
+       if (idx != len + BC_PROG_REQ_FUNCS) {
+
+               for (idx = 0; idx < p->strs.len; ++idx) {
+                       if (!strcmp(*((char **) bc_vec_item(&p->strs, idx)), str)) {
+                               len = idx;
+                               break;
+                       }
+               }
+
+               free(str);
+       }
+       else
+               bc_vec_push(&p->strs, &str);
+
+       res.t = BC_RESULT_STR;
+       res.d.id.idx = len;
+       bc_vec_pop(&p->results);
+       bc_vec_push(&p->results, &res);
+
+       return BC_STATUS_SUCCESS;
+
+num_err:
+       bc_num_free(&n);
+       return s;
+}
+
+static BcStatus bc_program_printStream(BcProgram *p)
+{
+       BcStatus s;
+       BcResult *r;
+       BcNum *n = NULL;
+       size_t idx;
+       char *str;
+
+       if (!BC_PROG_STACK(&p->results, 1)) return BC_STATUS_EXEC_STACK;
+       r = bc_vec_top(&p->results);
+
+       s = bc_program_num(p, r, &n, false);
+       if (s) return s;
+
+       if (BC_PROG_NUM(r, n))
+               s = bc_num_stream(n, &p->strmb, &p->nchars, p->len);
+       else {
+               idx = (r->t == BC_RESULT_STR) ? r->d.id.idx : n->rdx;
+               str = *((char **) bc_vec_item(&p->strs, idx));
+               bc_vm_printf(stdout, "%s", str);
+       }
+
+       return s;
+}
+
+static BcStatus bc_program_nquit(BcProgram *p)
+{
+       BcStatus s;
+       BcResult *opnd;
+       BcNum *num = NULL;
+       unsigned long val;
+
+       s = bc_program_prep(p, &opnd, &num);
+       if (s) return s;
+       s = bc_num_ulong(num, &val);
+       if (s) return s;
+
+       bc_vec_pop(&p->results);
+
+       if (p->stack.len < val)
+               return BC_STATUS_EXEC_STACK;
+       else if (p->stack.len == val)
+               return BC_STATUS_QUIT;
+
+       bc_vec_npop(&p->stack, val);
+
+       return s;
+}
+
+static BcStatus bc_program_execStr(BcProgram *p, char *code, size_t *bgn,
+                                   bool cond)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       BcResult *r;
+       char **str;
+       BcFunc *f;
+       BcParse prs;
+       BcInstPtr ip;
+       size_t fidx, sidx;
+       BcNum *n;
+       bool exec;
+
+       if (!BC_PROG_STACK(&p->results, 1)) return BC_STATUS_EXEC_STACK;
+
+       r = bc_vec_top(&p->results);
+
+       if (cond) {
+
+               BcVec *v;
+               char *name, *then_name = bc_program_name(code, bgn), *else_name = NULL;
+
+               if (code[*bgn] == BC_PARSE_STREND)
+                       (*bgn) += 1;
+               else
+                       else_name = bc_program_name(code, bgn);
+
+               exec = r->d.n.len != 0;
+
+               if (exec)
+                       name = then_name;
+               else if (else_name != NULL) {
+                       exec = true;
+                       name = else_name;
+               }
+
+               if (exec) {
+                       bc_program_search(p, name, &v, true);
+                       n = bc_vec_top(v);
+               }
+
+               free(then_name);
+               free(else_name);
+
+               if (!exec) goto exit;
+               if (!BC_PROG_STR(n)) {
+                       s = BC_STATUS_EXEC_BAD_TYPE;
+                       goto exit;
+               }
+
+               sidx = n->rdx;
+       }
+       else {
+
+               if (r->t == BC_RESULT_STR)
+                       sidx = r->d.id.idx;
+               else if (r->t == BC_RESULT_VAR) {
+                       s = bc_program_num(p, r, &n, false);
+                       if (s || !BC_PROG_STR(n)) goto exit;
+                       sidx = n->rdx;
+               }
+               else
+                       goto exit;
+       }
+
+       fidx = sidx + BC_PROG_REQ_FUNCS;
+
+       str = bc_vec_item(&p->strs, sidx);
+       f = bc_vec_item(&p->fns, fidx);
+
+       if (f->code.len == 0) {
+
+               p->parse_init(&prs, p, fidx);
+               s = bc_parse_text(&prs, *str);
+               if (s) goto err;
+               s = p->parse_expr(&prs, BC_PARSE_NOCALL);
+               if (s) goto err;
+
+               if (prs.l.t.t != BC_LEX_EOF) {
+                       s = BC_STATUS_PARSE_BAD_EXP;
+                       goto err;
+               }
+
+               bc_parse_free(&prs);
+       }
+
+       ip.idx = 0;
+       ip.len = p->results.len;
+       ip.func = fidx;
+
+       bc_vec_pop(&p->results);
+       bc_vec_push(&p->stack, &ip);
+
+       return BC_STATUS_SUCCESS;
+
+err:
+       bc_parse_free(&prs);
+       f = bc_vec_item(&p->fns, fidx);
+       bc_vec_npop(&f->code, f->code.len);
+exit:
+       bc_vec_pop(&p->results);
+       return s;
+}
+#endif // ENABLE_DC
+
+static BcStatus bc_program_pushGlobal(BcProgram *p, char inst)
+{
+       BcStatus s;
+       BcResult res;
+       unsigned long val;
+
+       res.t = inst - BC_INST_IBASE + BC_RESULT_IBASE;
+       if (inst == BC_INST_IBASE)
+               val = (unsigned long) p->ib_t;
+       else if (inst == BC_INST_SCALE)
+               val = (unsigned long) p->scale;
+       else
+               val = (unsigned long) p->ob_t;
+
+       bc_num_init(&res.d.n, BC_NUM_DEF_SIZE);
+       s = bc_num_ulong2num(&res.d.n, val);
+       if (s) goto err;
+       bc_vec_push(&p->results, &res);
+
+       return s;
+
+err:
+       bc_num_free(&res.d.n);
+       return s;
+}
+
+static void bc_program_free(BcProgram *p)
+{
+       bc_num_free(&p->ib);
+       bc_num_free(&p->ob);
+       bc_num_free(&p->hexb);
+#ifdef ENABLE_DC
+       bc_num_free(&p->strmb);
+#endif // ENABLE_DC
+       bc_vec_free(&p->fns);
+       bc_vec_free(&p->fn_map);
+       bc_vec_free(&p->vars);
+       bc_vec_free(&p->var_map);
+       bc_vec_free(&p->arrs);
+       bc_vec_free(&p->arr_map);
+       bc_vec_free(&p->strs);
+       bc_vec_free(&p->consts);
+       bc_vec_free(&p->results);
+       bc_vec_free(&p->stack);
+       bc_num_free(&p->last);
+       bc_num_free(&p->zero);
+       bc_num_free(&p->one);
+}
+
+static void bc_program_init(BcProgram *p, size_t line_len, BcParseInit init,
+                            BcParseExpr expr)
+{
+       size_t idx;
+       BcInstPtr ip;
+
+       memset(p, 0, sizeof(BcProgram));
+       memset(&ip, 0, sizeof(BcInstPtr));
+
+       p->nchars = p->scale = 0;
+       p->len = line_len;
+       p->parse_init = init;
+       p->parse_expr = expr;
+
+       bc_num_init(&p->ib, BC_NUM_DEF_SIZE);
+       bc_num_ten(&p->ib);
+       p->ib_t = 10;
+
+       bc_num_init(&p->ob, BC_NUM_DEF_SIZE);
+       bc_num_ten(&p->ob);
+       p->ob_t = 10;
+
+       bc_num_init(&p->hexb, BC_NUM_DEF_SIZE);
+       bc_num_ten(&p->hexb);
+       p->hexb.num[0] = 6;
+
+#ifdef ENABLE_DC
+       bc_num_init(&p->strmb, BC_NUM_DEF_SIZE);
+       bc_num_ulong2num(&p->strmb, UCHAR_MAX + 1);
+#endif // ENABLE_DC
+
+       bc_num_init(&p->last, BC_NUM_DEF_SIZE);
+       bc_num_zero(&p->last);
+
+       bc_num_init(&p->zero, BC_NUM_DEF_SIZE);
+       bc_num_zero(&p->zero);
+
+       bc_num_init(&p->one, BC_NUM_DEF_SIZE);
+       bc_num_one(&p->one);
+
+       bc_vec_init(&p->fns, sizeof(BcFunc), bc_func_free);
+       bc_map_init(&p->fn_map);
+
+       bc_program_addFunc(p, xstrdup(bc_func_main), &idx);
+       bc_program_addFunc(p, xstrdup(bc_func_read), &idx);
+
+       bc_vec_init(&p->vars, sizeof(BcVec), bc_vec_free);
+       bc_map_init(&p->var_map);
+
+       bc_vec_init(&p->arrs, sizeof(BcVec), bc_vec_free);
+       bc_map_init(&p->arr_map);
+
+       bc_vec_init(&p->strs, sizeof(char *), bc_string_free);
+       bc_vec_init(&p->consts, sizeof(char *), bc_string_free);
+       bc_vec_init(&p->results, sizeof(BcResult), bc_result_free);
+       bc_vec_init(&p->stack, sizeof(BcInstPtr), NULL);
+       bc_vec_push(&p->stack, &ip);
+}
+
+static void bc_program_addFunc(BcProgram *p, char *name, size_t *idx)
+{
+       BcStatus s;
+       BcId entry, *entry_ptr;
+       BcFunc f;
+
+       entry.name = name;
+       entry.idx = p->fns.len;
+
+       s = bc_map_insert(&p->fn_map, &entry, idx);
+       if (s) free(name);
+
+       entry_ptr = bc_vec_item(&p->fn_map, *idx);
+       *idx = entry_ptr->idx;
+
+       if (s == BC_STATUS_VEC_ITEM_EXISTS) {
+
+               BcFunc *func = bc_vec_item(&p->fns, entry_ptr->idx);
+
+               // We need to reset these, so the function can be repopulated.
+               func->nparams = 0;
+               bc_vec_npop(&func->autos, func->autos.len);
+               bc_vec_npop(&func->code, func->code.len);
+               bc_vec_npop(&func->labels, func->labels.len);
+       }
+       else {
+               bc_func_init(&f);
+               bc_vec_push(&p->fns, &f);
+       }
+}
+
+static BcStatus bc_program_reset(BcProgram *p, BcStatus s)
+{
+       BcFunc *f;
+       BcInstPtr *ip;
+
+       bc_vec_npop(&p->stack, p->stack.len - 1);
+       bc_vec_npop(&p->results, p->results.len);
+
+       f = bc_vec_item(&p->fns, 0);
+       ip = bc_vec_top(&p->stack);
+       ip->idx = f->code.len;
+
+       if (!s && bcg.signe && !bcg.tty) return BC_STATUS_QUIT;
+
+       bcg.sigc += bcg.signe;
+       bcg.signe = bcg.sig != bcg.sigc;
+
+       if (!s || s == BC_STATUS_EXEC_SIGNAL) {
+               if (bcg.ttyin) {
+                       bc_vm_puts(bc_program_ready_msg, stderr);
+                       bc_vm_fflush(stderr);
+                       s = BC_STATUS_SUCCESS;
+               }
+               else
+                       s = BC_STATUS_QUIT;
+       }
+
+       return s;
+}
+
+static BcStatus bc_program_exec(BcProgram *p)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       size_t idx;
+       BcResult r, *ptr;
+       BcNum *num;
+       BcInstPtr *ip = bc_vec_top(&p->stack);
+       BcFunc *func = bc_vec_item(&p->fns, ip->func);
+       char *code = func->code.v;
+       bool cond = false;
+
+       while (!s && ip->idx < func->code.len) {
+
+               char inst = code[(ip->idx)++];
+
+               switch (inst) {
+
+#ifdef ENABLE_BC
+                       case BC_INST_JUMP_ZERO:
+                       {
+                               s = bc_program_prep(p, &ptr, &num);
+                               if (s) return s;
+                               cond = !bc_num_cmp(num, &p->zero);
+                               bc_vec_pop(&p->results);
+                       }
+                       // Fallthrough.
+                       case BC_INST_JUMP:
+                       {
+                               size_t *addr;
+                               idx = bc_program_index(code, &ip->idx);
+                               addr = bc_vec_item(&func->labels, idx);
+                               if (inst == BC_INST_JUMP || cond) ip->idx = *addr;
+                               break;
+                       }
+
+                       case BC_INST_CALL:
+                       {
+                               s = bc_program_call(p, code, &ip->idx);
+                               break;
+                       }
+
+                       case BC_INST_INC_PRE:
+                       case BC_INST_DEC_PRE:
+                       case BC_INST_INC_POST:
+                       case BC_INST_DEC_POST:
+                       {
+                               s = bc_program_incdec(p, inst);
+                               break;
+                       }
+
+                       case BC_INST_HALT:
+                       {
+                               s = BC_STATUS_QUIT;
+                               break;
+                       }
+
+                       case BC_INST_RET:
+                       case BC_INST_RET0:
+                       {
+                               s = bc_program_return(p, inst);
+                               break;
+                       }
+
+                       case BC_INST_BOOL_OR:
+                       case BC_INST_BOOL_AND:
+#endif // ENABLE_BC
+                       case BC_INST_REL_EQ:
+                       case BC_INST_REL_LE:
+                       case BC_INST_REL_GE:
+                       case BC_INST_REL_NE:
+                       case BC_INST_REL_LT:
+                       case BC_INST_REL_GT:
+                       {
+                               s = bc_program_logical(p, inst);
+                               break;
+                       }
+
+                       case BC_INST_READ:
+                       {
+                               s = bc_program_read(p);
+                               break;
+                       }
+
+                       case BC_INST_VAR:
+                       {
+                               s = bc_program_pushVar(p, code, &ip->idx, false, false);
+                               break;
+                       }
+
+                       case BC_INST_ARRAY_ELEM:
+                       case BC_INST_ARRAY:
+                       {
+                               s = bc_program_pushArray(p, code, &ip->idx, inst);
+                               break;
+                       }
+
+                       case BC_INST_LAST:
+                       {
+                               r.t = BC_RESULT_LAST;
+                               bc_vec_push(&p->results, &r);
+                               break;
+                       }
+
+                       case BC_INST_IBASE:
+                       case BC_INST_SCALE:
+                       case BC_INST_OBASE:
+                       {
+                               s = bc_program_pushGlobal(p, inst);
+                               break;
+                       }
+
+                       case BC_INST_SCALE_FUNC:
+                       case BC_INST_LENGTH:
+                       case BC_INST_SQRT:
+                       {
+                               s = bc_program_builtin(p, inst);
+                               break;
+                       }
+
+                       case BC_INST_NUM:
+                       {
+                               r.t = BC_RESULT_CONSTANT;
+                               r.d.id.idx = bc_program_index(code, &ip->idx);
+                               bc_vec_push(&p->results, &r);
+                               break;
+                       }
+
+                       case BC_INST_POP:
+                       {
+                               if (!BC_PROG_STACK(&p->results, 1))
+                                       s = BC_STATUS_EXEC_STACK;
+                               else
+                                       bc_vec_pop(&p->results);
+                               break;
+                       }
+
+                       case BC_INST_POP_EXEC:
+                       {
+                               bc_vec_pop(&p->stack);
+                               break;
+                       }
+
+                       case BC_INST_PRINT:
+                       case BC_INST_PRINT_POP:
+                       case BC_INST_PRINT_STR:
+                       {
+                               s = bc_program_print(p, inst, 0);
+                               break;
+                       }
+
+                       case BC_INST_STR:
+                       {
+                               r.t = BC_RESULT_STR;
+                               r.d.id.idx = bc_program_index(code, &ip->idx);
+                               bc_vec_push(&p->results, &r);
+                               break;
+                       }
+
+                       case BC_INST_POWER:
+                       case BC_INST_MULTIPLY:
+                       case BC_INST_DIVIDE:
+                       case BC_INST_MODULUS:
+                       case BC_INST_PLUS:
+                       case BC_INST_MINUS:
+                       {
+                               s = bc_program_op(p, inst);
+                               break;
+                       }
+
+                       case BC_INST_BOOL_NOT:
+                       {
+                               s = bc_program_prep(p, &ptr, &num);
+                               if (s) return s;
+
+                               bc_num_init(&r.d.n, BC_NUM_DEF_SIZE);
+                               (!bc_num_cmp(num, &p->zero) ? bc_num_one : bc_num_zero)(&r.d.n);
+                               bc_program_retire(p, &r, BC_RESULT_TEMP);
+
+                               break;
+                       }
+
+                       case BC_INST_NEG:
+                       {
+                               s = bc_program_negate(p);
+                               break;
+                       }
+
+#ifdef ENABLE_BC
+                       case BC_INST_ASSIGN_POWER:
+                       case BC_INST_ASSIGN_MULTIPLY:
+                       case BC_INST_ASSIGN_DIVIDE:
+                       case BC_INST_ASSIGN_MODULUS:
+                       case BC_INST_ASSIGN_PLUS:
+                       case BC_INST_ASSIGN_MINUS:
+#endif // ENABLE_BC
+                       case BC_INST_ASSIGN:
+                       {
+                               s = bc_program_assign(p, inst);
+                               break;
+                       }
+#ifdef ENABLE_DC
+                       case BC_INST_MODEXP:
+                       {
+                               s = bc_program_modexp(p);
+                               break;
+                       }
+
+                       case BC_INST_DIVMOD:
+                       {
+                               s = bc_program_divmod(p);
+                               break;
+                       }
+
+                       case BC_INST_EXECUTE:
+                       case BC_INST_EXEC_COND:
+                       {
+                               cond = inst == BC_INST_EXEC_COND;
+                               s = bc_program_execStr(p, code, &ip->idx, cond);
+                               break;
+                       }
+
+                       case BC_INST_PRINT_STACK:
+                       {
+                               for (idx = 0; !s && idx < p->results.len; ++idx)
+                                       s = bc_program_print(p, BC_INST_PRINT, idx);
+                               break;
+                       }
+
+                       case BC_INST_CLEAR_STACK:
+                       {
+                               bc_vec_npop(&p->results, p->results.len);
+                               break;
+                       }
+
+                       case BC_INST_STACK_LEN:
+                       {
+                               s = bc_program_stackLen(p);
+                               break;
+                       }
+
+                       case BC_INST_DUPLICATE:
+                       {
+                               if (!BC_PROG_STACK(&p->results, 1)) return BC_STATUS_EXEC_STACK;
+                               ptr = bc_vec_top(&p->results);
+                               bc_result_copy(&r, ptr);
+                               bc_vec_push(&p->results, &r);
+                               break;
+                       }
+
+                       case BC_INST_SWAP:
+                       {
+                               BcResult *ptr2;
+
+                               if (!BC_PROG_STACK(&p->results, 2)) return BC_STATUS_EXEC_STACK;
+
+                               ptr = bc_vec_item_rev(&p->results, 0);
+                               ptr2 = bc_vec_item_rev(&p->results, 1);
+                               memcpy(&r, ptr, sizeof(BcResult));
+                               memcpy(ptr, ptr2, sizeof(BcResult));
+                               memcpy(ptr2, &r, sizeof(BcResult));
+
+                               break;
+                       }
+
+                       case BC_INST_ASCIIFY:
+                       {
+                               s = bc_program_asciify(p);
+                               break;
+                       }
+
+                       case BC_INST_PRINT_STREAM:
+                       {
+                               s = bc_program_printStream(p);
+                               break;
+                       }
+
+                       case BC_INST_LOAD:
+                       case BC_INST_PUSH_VAR:
+                       {
+                               bool copy = inst == BC_INST_LOAD;
+                               s = bc_program_pushVar(p, code, &ip->idx, true, copy);
+                               break;
+                       }
+
+                       case BC_INST_PUSH_TO_VAR:
+                       {
+                               char *name = bc_program_name(code, &ip->idx);
+                               s = bc_program_copyToVar(p, name, true);
+                               free(name);
+                               break;
+                       }
+
+                       case BC_INST_QUIT:
+                       {
+                               if (p->stack.len <= 2)
+                                       s = BC_STATUS_QUIT;
+                               else
+                                       bc_vec_npop(&p->stack, 2);
+                               break;
+                       }
+
+                       case BC_INST_NQUIT:
+                       {
+                               s = bc_program_nquit(p);
+                               break;
+                       }
+#endif // ENABLE_DC
+               }
+
+               if ((s && s != BC_STATUS_QUIT) || bcg.signe) s = bc_program_reset(p, s);
+
+               // If the stack has changed, pointers may be invalid.
+               ip = bc_vec_top(&p->stack);
+               func = bc_vec_item(&p->fns, ip->func);
+               code = func->code.v;
+       }
+
+       return s;
+}
+
+#if ENABLE_FEATURE_BC_SIGNALS
+static void bc_vm_sig(int sig)
+{
+       int err = errno;
+       size_t len = strlen(bcg.sig_msg);
+       if (sig == SIGINT && write(2, bcg.sig_msg, len) == (ssize_t) len) {
+               bcg.signe = bcg.sig == bcg.sigc;
+               bcg.sig += bcg.signe;
+       }
+       errno = err;
+}
+#endif // ENABLE_FEATURE_BC_SIGNALS
+
+static void bc_vm_info(const char *const help)
+{
+       bc_vm_printf(stdout, "%s %s\n", bcg.name, "1.1");
+       bc_vm_puts(bc_copyright, stdout);
+       if (help) bc_vm_printf(stdout, help, bcg.name);
+}
+
+static BcStatus bc_vm_error(BcStatus s, const char *file, size_t line)
+{
+       if (!s || s > BC_STATUS_VEC_ITEM_EXISTS) return s;
+
+       bc_vm_printf(stderr, bc_err_fmt, bc_errs[bc_err_ids[s]], bc_err_msgs[s]);
+       bc_vm_printf(stderr, "    %s", file);
+       bc_vm_printf(stderr, bc_err_line + 4 * !line, line);
+
+       return s * (!bcg.ttyin || !!strcmp(file, bc_program_stdin_name));
+}
+
+#ifdef ENABLE_BC
+static BcStatus bc_vm_posixError(BcStatus s, const char *file, size_t line,
+                                 const char *msg)
+{
+       int p = (int) bcg.posix, w = (int) bcg.warn;
+       const char *const fmt = p ? bc_err_fmt : bc_warn_fmt;
+
+       if (!(p || w) || s < BC_STATUS_POSIX_NAME_LEN) return BC_STATUS_SUCCESS;
+
+       bc_vm_printf(stderr, fmt, bc_errs[bc_err_ids[s]], bc_err_msgs[s]);
+       if (msg) bc_vm_printf(stderr, "    %s\n", msg);
+       bc_vm_printf(stderr, "    %s", file);
+       bc_vm_printf(stderr, bc_err_line + 4 * !line, line);
+
+       return s * (!bcg.ttyin && !!p);
+}
+
+static BcStatus bc_vm_envArgs(BcVm *vm)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       BcVec v;
+       char *env_args = getenv(bc_args_env_name), *buf;
+
+       if (!env_args) return s;
+
+       vm->env_args = xstrdup(env_args);
+       buf = vm->env_args;
+
+       bc_vec_init(&v, sizeof(char *), NULL);
+       bc_vec_push(&v, &bc_args_env_name);
+
+       while (*buf != 0) {
+               if (!isspace(*buf)) {
+                       bc_vec_push(&v, &buf);
+                       while (*buf != 0 && !isspace(*buf)) ++buf;
+                       if (*buf != 0) (*(buf++)) = '\0';
+               }
+               else
+                       ++buf;
+       }
+
+       s = bc_args((int) v.len, (char **) v.v, &vm->flags, &vm->files);
+
+       bc_vec_free(&v);
+
+       return s;
+}
+#endif // ENABLE_BC
+
+static size_t bc_vm_envLen(const char *var)
+{
+       char *lenv = getenv(var);
+       size_t i, len = BC_NUM_PRINT_WIDTH;
+       int num;
+
+       if (!lenv) return len;
+
+       len = strlen(lenv);
+
+       for (num = 1, i = 0; num && i < len; ++i) num = isdigit(lenv[i]);
+       if (num) {
+               len = (size_t) atoi(lenv) - 1;
+               if (len < 2 || len >= INT32_MAX) len = BC_NUM_PRINT_WIDTH;
+       }
+       else
+               len = BC_NUM_PRINT_WIDTH;
+
+       return len;
+}
+
+static void bc_vm_exit(BcStatus s)
+{
+       bc_vm_printf(stderr, bc_err_fmt, bc_errs[bc_err_ids[s]], bc_err_msgs[s]);
+       exit((int) s);
+}
+
+static void bc_vm_printf(FILE *restrict f, const char *fmt, ...)
+{
+       va_list args;
+       bool bad;
+
+       va_start(args, fmt);
+       bad = vfprintf(f, fmt, args) < 0;
+       va_end(args);
+
+       if (bad) bc_vm_exit(BC_STATUS_IO_ERR);
+}
+
+static void bc_vm_puts(const char *str, FILE *restrict f)
+{
+       if (fputs(str, f) == EOF) bc_vm_exit(BC_STATUS_IO_ERR);
+}
+
+static void bc_vm_putchar(int c)
+{
+       if (putchar(c) == EOF) bc_vm_exit(BC_STATUS_IO_ERR);
+}
+
+static void bc_vm_fflush(FILE *restrict f)
+{
+       if (fflush(f) == EOF) bc_vm_exit(BC_STATUS_IO_ERR);
+}
+
+static BcStatus bc_vm_process(BcVm *vm, const char *text)
+{
+       BcStatus s = bc_parse_text(&vm->prs, text);
+
+       s = bc_vm_error(s, vm->prs.l.f, vm->prs.l.line);
+       if (s) return s;
+
+       while (vm->prs.l.t.t != BC_LEX_EOF) {
+
+               s = vm->prs.parse(&vm->prs);
+
+               if (s == BC_STATUS_LIMITS) {
+
+                       bc_vm_putchar('\n');
+                       bc_vm_printf(stdout, "BC_BASE_MAX     = %lu\n", BC_MAX_OBASE);
+                       bc_vm_printf(stdout, "BC_DIM_MAX      = %lu\n", BC_MAX_DIM);
+                       bc_vm_printf(stdout, "BC_SCALE_MAX    = %lu\n", BC_MAX_SCALE);
+                       bc_vm_printf(stdout, "BC_STRING_MAX   = %lu\n", BC_MAX_STRING);
+                       bc_vm_printf(stdout, "BC_NAME_MAX     = %lu\n", BC_MAX_NAME);
+                       bc_vm_printf(stdout, "BC_NUM_MAX      = %lu\n", BC_MAX_NUM);
+                       bc_vm_printf(stdout, "Max Exponent    = %lu\n", BC_MAX_EXP);
+                       bc_vm_printf(stdout, "Number of Vars  = %lu\n", BC_MAX_VARS);
+                       bc_vm_putchar('\n');
+
+                       s = BC_STATUS_SUCCESS;
+               }
+               else {
+                       if (s == BC_STATUS_QUIT) return s;
+                       s = bc_vm_error(s, vm->prs.l.f, vm->prs.l.line);
+                       if (s) return s;
+               }
+       }
+
+       if (BC_PARSE_CAN_EXEC(&vm->prs)) {
+               s = bc_program_exec(&vm->prog);
+               if (!s && bcg.tty) bc_vm_fflush(stdout);
+               if (s && s != BC_STATUS_QUIT)
+                       s = bc_vm_error(bc_program_reset(&vm->prog, s), vm->prs.l.f, 0);
+       }
+
+       return s;
+}
+
+static BcStatus bc_vm_file(BcVm *vm, const char *file)
+{
+       BcStatus s;
+       char *data;
+       BcFunc *main_func;
+       BcInstPtr *ip;
+
+       vm->prog.file = file;
+       s = bc_read_file(file, &data);
+       if (s) return bc_vm_error(s, file, 0);
+
+       bc_lex_file(&vm->prs.l, file);
+       s = bc_vm_process(vm, data);
+       if (s) goto err;
+
+       main_func = bc_vec_item(&vm->prog.fns, BC_PROG_MAIN);
+       ip = bc_vec_item(&vm->prog.stack, 0);
+
+       if (main_func->code.len < ip->idx) s = BC_STATUS_EXEC_FILE_NOT_EXECUTABLE;
+
+err:
+       free(data);
+       return s;
+}
+
+static BcStatus bc_vm_stdin(BcVm *vm)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       BcVec buf, buffer;
+       char c;
+       size_t len, i, str = 0;
+       bool comment = false, notend;
+
+       vm->prog.file = bc_program_stdin_name;
+       bc_lex_file(&vm->prs.l, bc_program_stdin_name);
+
+       bc_vec_init(&buffer, sizeof(char), NULL);
+       bc_vec_init(&buf, sizeof(char), NULL);
+       bc_vec_pushByte(&buffer, '\0');
+
+       // This loop is complex because the vm tries not to send any lines that end
+       // with a backslash to the parser. The reason for that is because the parser
+       // treats a backslash+newline combo as whitespace, per the bc spec. In that
+       // case, and for strings and comments, the parser will expect more stuff.
+       for (s = bc_read_line(&buf, ">>> "); !s; s = bc_read_line(&buf, ">>> ")) {
+
+               char *string = buf.v;
+
+               len = buf.len - 1;
+
+               if (len == 1) {
+                       if (str && buf.v[0] == vm->exe.send)
+                               str -= 1;
+                       else if (buf.v[0] == vm->exe.sbgn)
+                               str += 1;
+               }
+               else if (len > 1 || comment) {
+
+                       for (i = 0; i < len; ++i) {
+
+                               notend = len > i + 1;
+                               c = string[i];
+
+                               if (i - 1 > len || string[i - 1] != '\\') {
+                                       if (vm->exe.sbgn == vm->exe.send)
+                                               str ^= c == vm->exe.sbgn;
+                                       else if (c == vm->exe.send)
+                                               str -= 1;
+                                       else if (c == vm->exe.sbgn)
+                                               str += 1;
+                               }
+
+                               if (c == '/' && notend && !comment && string[i + 1] == '*') {
+                                       comment = true;
+                                       break;
+                               }
+                               else if (c == '*' && notend && comment && string[i + 1] == '/')
+                                       comment = false;
+                       }
+
+                       if (str || comment || string[len - 2] == '\\') {
+                               bc_vec_concat(&buffer, buf.v);
+                               continue;
+                       }
+               }
+
+               bc_vec_concat(&buffer, buf.v);
+               s = bc_vm_process(vm, buffer.v);
+               if (s) goto err;
+
+               bc_vec_npop(&buffer, buffer.len);
+       }
+
+       if (s == BC_STATUS_BIN_FILE) s = bc_vm_error(s, vm->prs.l.f, 0);
+
+       // I/O error will always happen when stdin is
+       // closed. It's not a problem in that case.
+       s = s == BC_STATUS_IO_ERR || s == BC_STATUS_QUIT ? BC_STATUS_SUCCESS : s;
+
+       if (str)
+               s = bc_vm_error(BC_STATUS_LEX_NO_STRING_END, vm->prs.l.f,
+                               vm->prs.l.line);
+       else if (comment)
+               s = bc_vm_error(BC_STATUS_LEX_NO_COMMENT_END, vm->prs.l.f,
+                               vm->prs.l.line);
+
+err:
+       bc_vec_free(&buf);
+       bc_vec_free(&buffer);
+       return s;
+}
+
+static BcStatus bc_vm_exec(BcVm *vm)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       size_t i;
+
+#ifdef ENABLE_BC
+       if (vm->flags & BC_FLAG_L) {
+
+               bc_lex_file(&vm->prs.l, bc_lib_name);
+               s = bc_parse_text(&vm->prs, bc_lib);
+
+               while (!s && vm->prs.l.t.t != BC_LEX_EOF) s = vm->prs.parse(&vm->prs);
+
+               if (s) return s;
+               s = bc_program_exec(&vm->prog);
+               if (s) return s;
+       }
+#endif // ENABLE_BC
+
+       for (i = 0; !s && i < vm->files.len; ++i)
+               s = bc_vm_file(vm, *((char **) bc_vec_item(&vm->files, i)));
+       if (s && s != BC_STATUS_QUIT) return s;
+
+       if (bcg.bc || !vm->files.len) s = bc_vm_stdin(vm);
+       if (!s && !BC_PARSE_CAN_EXEC(&vm->prs)) s = bc_vm_process(vm, "");
+
+       return s == BC_STATUS_QUIT ? BC_STATUS_SUCCESS : s;
+}
+
+static void bc_vm_free(BcVm *vm)
+{
+       bc_vec_free(&vm->files);
+       bc_program_free(&vm->prog);
+       bc_parse_free(&vm->prs);
+       free(vm->env_args);
+}
+
+static BcStatus bc_vm_init(BcVm *vm, BcVmExe exe, const char *env_len)
+{
+       BcStatus s = BC_STATUS_SUCCESS;
+       size_t len = bc_vm_envLen(env_len);
+#if ENABLE_FEATURE_BC_SIGNALS
+       struct sigaction sa;
+
+       sigemptyset(&sa.sa_mask);
+       sa.sa_handler = bc_vm_sig;
+       sa.sa_flags = 0;
+       sigaction(SIGINT, &sa, NULL);
+#endif // ENABLE_FEATURE_BC_SIGNALS
+
+       memset(vm, 0, sizeof(BcVm));
+
+       vm->exe = exe;
+       vm->flags = 0;
+       vm->env_args = NULL;
+
+       bc_vec_init(&vm->files, sizeof(char *), NULL);
+
+#ifdef ENABLE_BC
+       vm->flags |= BC_FLAG_S * bcg.bc * (getenv("POSIXLY_CORRECT") != NULL);
+       if (bcg.bc) s = bc_vm_envArgs(vm);
+#endif // ENABLE_BC
+
+       bc_program_init(&vm->prog, len, exe.init, exe.exp);
+       exe.init(&vm->prs, &vm->prog, BC_PROG_MAIN);
+
+       return s;
+}
+
+static BcStatus bc_vm_run(int argc, char *argv[], BcVmExe exe,
+                          const char *env_len)
+{
+       BcStatus st;
+       BcVm vm;
+
+       st = bc_vm_init(&vm, exe, env_len);
+       if (st) goto exit;
+       st = bc_args(argc, argv, &vm.flags, &vm.files);
+       if (st) goto exit;
+
+       bcg.ttyin = isatty(0);
+       bcg.tty = bcg.ttyin || (vm.flags & BC_FLAG_I) || isatty(1);
+
+#ifdef ENABLE_BC
+       bcg.posix = vm.flags & BC_FLAG_S;
+       bcg.warn = vm.flags & BC_FLAG_W;
+#endif // ENABLE_BC
+#ifdef ENABLE_DC
+       bcg.exreg = vm.flags & BC_FLAG_X;
+#endif // ENABLE_DC
+
+       if (bcg.ttyin && !(vm.flags & BC_FLAG_Q)) bc_vm_info(NULL);
+       st = bc_vm_exec(&vm);
+
+exit:
+       bc_vm_free(&vm);
+       return st;
+}
+
+#ifdef ENABLE_BC
+BcStatus bc_main(int argc, char *argv[])
+{
+       BcVmExe exec;
+
+       bcg.bc = true;
+       bcg.name = bc_name;
+#if ENABLE_FEATURE_BC_SIGNALS
+       bcg.sig_msg = bc_sig_msg;
+#endif // ENABLE_FEATURE_BC_SIGNALS
+
+       exec.init = bc_parse_init;
+       exec.exp = bc_parse_expression;
+       exec.sbgn = exec.send = '"';
+
+       return bc_vm_run(argc, argv, exec, "BC_LINE_LENGTH");
+}
+#endif // ENABLE_BC
+
+#ifdef ENABLE_DC
+BcStatus dc_main(int argc, char *argv[])
+{
+       BcVmExe exec;
+
+       bcg.bc = false;
+       bcg.name = dc_name;
+#if ENABLE_FEATURE_BC_SIGNALS
+       bcg.sig_msg = dc_sig_msg;
+#endif // ENABLE_FEATURE_BC_SIGNALS
+
+       exec.init = dc_parse_init;
+       exec.exp = dc_parse_expr;
+       exec.sbgn = '[';
+       exec.send = ']';
+
+       return bc_vm_run(argc, argv, exec, "DC_LINE_LENGTH");
+}
+#endif // ENABLE_DC
index b922a7184d7d2fe2934662fca61b7ad50dd5cef6..d58f97e91d344f2f6f378a9f050d90aab689673d 100644 (file)
@@ -1,48 +1,49 @@
+#if 0 //TODO: use if bc is not selected
 /* vi: set sw=4 ts=4: */
 /*
  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
-//config:config DC
-//config:      bool "dc (4.2 kb)"
-//config:      default y
-//config:      help
-//config:      Dc is a reverse-polish desk calculator which supports unlimited
-//config:      precision arithmetic.
-//config:
-//config:config FEATURE_DC_LIBM
-//config:      bool "Enable power and exp functions (requires libm)"
-//config:      default y
-//config:      depends on DC
-//config:      help
-//config:      Enable power and exp functions.
-//config:      NOTE: This will require libm to be present for linking.
-
-//applet:IF_DC(APPLET(dc, BB_DIR_USR_BIN, BB_SUID_DROP))
-
-//kbuild:lib-$(CONFIG_DC) += dc.o
-
-//usage:#define dc_trivial_usage
-//usage:       "EXPRESSION..."
-//usage:
-//usage:#define dc_full_usage "\n\n"
-//usage:       "Tiny RPN calculator. Operations:\n"
-//usage:       "+, add, -, sub, *, mul, /, div, %, mod, "IF_FEATURE_DC_LIBM("**, exp, ")"and, or, not, xor,\n"
-//usage:       "p - print top of the stack (without popping),\n"
-//usage:       "f - print entire stack,\n"
-//usage:       "o - pop the value and set output radix (must be 10, 16, 8 or 2).\n"
-//usage:       "Examples: 'dc 2 2 add p' -> 4, 'dc 8 8 mul 2 2 + / p' -> 16"
-//usage:
-//usage:#define dc_example_usage
-//usage:       "$ dc 2 2 + p\n"
-//usage:       "4\n"
-//usage:       "$ dc 8 8 \\* 2 2 + / p\n"
-//usage:       "16\n"
-//usage:       "$ dc 0 1 and p\n"
-//usage:       "0\n"
-//usage:       "$ dc 0 1 or p\n"
-//usage:       "1\n"
-//usage:       "$ echo 72 9 div 8 mul p | dc\n"
-//usage:       "64\n"
+       //config:config DC
+       //config:       bool "dc (4.2 kb)"
+       //config:       default y
+       //config:       help
+       //config:       Dc is a reverse-polish desk calculator which supports unlimited
+       //config:       precision arithmetic.
+       //config:
+       //config:config FEATURE_DC_LIBM
+       //config:       bool "Enable power and exp functions (requires libm)"
+       //config:       default y
+       //config:       depends on DC
+       //config:       help
+       //config:       Enable power and exp functions.
+       //config:       NOTE: This will require libm to be present for linking.
+
+       //applet:IF_DC(APPLET(dc, BB_DIR_USR_BIN, BB_SUID_DROP))
+
+       //kbuild:lib-$(CONFIG_DC) += dc.o
+
+       //usage:#define dc_trivial_usage
+       //usage:       "EXPRESSION..."
+       //usage:
+       //usage:#define dc_full_usage "\n\n"
+       //usage:       "Tiny RPN calculator. Operations:\n"
+       //usage:       "+, add, -, sub, *, mul, /, div, %, mod, "IF_FEATURE_DC_LIBM("**, exp, ")"and, or, not, xor,\n"
+       //usage:       "p - print top of the stack (without popping),\n"
+       //usage:       "f - print entire stack,\n"
+       //usage:       "o - pop the value and set output radix (must be 10, 16, 8 or 2).\n"
+       //usage:       "Examples: 'dc 2 2 add p' -> 4, 'dc 8 8 mul 2 2 + / p' -> 16"
+       //usage:
+       //usage:#define dc_example_usage
+       //usage:       "$ dc 2 2 + p\n"
+       //usage:       "4\n"
+       //usage:       "$ dc 8 8 \\* 2 2 + / p\n"
+       //usage:       "16\n"
+       //usage:       "$ dc 0 1 and p\n"
+       //usage:       "0\n"
+       //usage:       "$ dc 0 1 or p\n"
+       //usage:       "1\n"
+       //usage:       "$ echo 72 9 div 8 mul p | dc\n"
+       //usage:       "64\n"
 
 #include "libbb.h"
 #include "common_bufsiz.h"
@@ -302,3 +303,4 @@ int dc_main(int argc UNUSED_PARAM, char **argv)
        }
        return EXIT_SUCCESS;
 }
+#endif