1 /* vi: set sw=4 ts=4: */
3 * A prototype Bourne shell grammar parser.
4 * Intended to follow the original Thompson and Ritchie
5 * "small and simple is beautiful" philosophy, which
6 * incidentally is a good match to today's BusyBox.
8 * Copyright (C) 2000,2001 Larry Doolittle <larry@doolittle.boa.org>
9 * Copyright (C) 2008,2009 Denys Vlasenko <vda.linux@googlemail.com>
11 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
14 * The parser routines proper are all original material, first
15 * written Dec 2000 and Jan 2001 by Larry Doolittle. The
16 * execution engine, the builtins, and much of the underlying
17 * support has been adapted from busybox-0.49pre's lash, which is
18 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
19 * written by Erik Andersen <andersen@codepoet.org>. That, in turn,
20 * is based in part on ladsh.c, by Michael K. Johnson and Erik W.
21 * Troan, which they placed in the public domain. I don't know
22 * how much of the Johnson/Troan code has survived the repeated
26 * o_addchr derived from similar w_addchar function in glibc-2.2.
27 * parse_redirect, redirect_opt_num, and big chunks of main
28 * and many builtins derived from contributions by Erik Andersen.
29 * Miscellaneous bugfixes from Matt Kraai.
31 * There are two big (and related) architecture differences between
32 * this parser and the lash parser. One is that this version is
33 * actually designed from the ground up to understand nearly all
34 * of the Bourne grammar. The second, consequential change is that
35 * the parser and input reader have been turned inside out. Now,
36 * the parser is in control, and asks for input as needed. The old
37 * way had the input reader in control, and it asked for parsing to
38 * take place as needed. The new way makes it much easier to properly
39 * handle the recursion implicit in the various substitutions, especially
40 * across continuation lines.
43 * grep for "TODO" and fix (some of them are easy)
44 * special variables (done: PWD, PPID, RANDOM)
47 * follow IFS rules more precisely, including update semantics
48 * builtins mandated by standards we don't support:
49 * [un]alias, command, fc, getopts, newgrp, readonly, times
50 * make complex ${var%...} constructs support optional
51 * make here documents optional
54 * redirection of stdout+stderr: &> and >&
55 * reserved words: function select
56 * advanced test: [[ ]]
57 * process substitution: <(list) and >(list)
60 * Each EXPR is an arithmetic expression (ARITHMETIC EVALUATION)
61 * If the last arg evaluates to 0, let returns 1; 0 otherwise.
62 * NB: let `echo 'a=a + 1'` - error (IOW: multi-word expansion is used)
64 * The EXPR is evaluated according to ARITHMETIC EVALUATION.
65 * This is exactly equivalent to let "EXPR".
66 * $[EXPR]: synonym for $((EXPR))
69 * In bash, export builtin is special, its arguments are assignments
70 * and therefore expansion of them should be "one-word" expansion:
71 * $ export i=`echo 'a b'` # export has one arg: "i=a b"
73 * $ ls i=`echo 'a b'` # ls has two args: "i=a" and "b"
74 * ls: cannot access i=a: No such file or directory
75 * ls: cannot access b: No such file or directory
76 * Note1: same applies to local builtin.
77 * Note2: bash 3.2.33(1) does this only if export word itself
79 * $ export i=`echo 'aaa bbb'`; echo "$i"
81 * $ "export" i=`echo 'aaa bbb'`; echo "$i"
84 #if !(defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__NetBSD__) \
85 || defined(__APPLE__) \
87 # include <malloc.h> /* for malloc_trim */
90 /* #include <dmalloc.h> */
94 #include <sys/utsname.h> /* for setting $HOSTNAME */
96 #include "busybox.h" /* for APPLET_IS_NOFORK/NOEXEC */
98 #include "shell_common.h"
101 #if ENABLE_HUSH_RANDOM_SUPPORT
104 # define CLEAR_RANDOM_T(rnd) ((void)0)
107 # define PIPE_BUF 4096 /* amount of buffering in a pipe */
111 //config: bool "hush"
114 //config: hush is a small shell (25k). It handles the normal flow control
115 //config: constructs such as if/then/elif/else/fi, for/in/do/done, while loops,
116 //config: case/esac. Redirections, here documents, $((arithmetic))
117 //config: and functions are supported.
119 //config: It will compile and work on no-mmu systems.
121 //config: It does not handle select, aliases, tilde expansion,
122 //config: &>file and >&file redirection of stdout+stderr.
124 //config:config HUSH_BASH_COMPAT
125 //config: bool "bash-compatible extensions"
127 //config: depends on HUSH
129 //config: Enable bash-compatible extensions.
131 //config:config HUSH_BRACE_EXPANSION
132 //config: bool "Brace expansion"
134 //config: depends on HUSH_BASH_COMPAT
136 //config: Enable {abc,def} extension.
138 //config:config HUSH_HELP
139 //config: bool "help builtin"
141 //config: depends on HUSH
143 //config: Enable help builtin in hush. Code size + ~1 kbyte.
145 //config:config HUSH_INTERACTIVE
146 //config: bool "Interactive mode"
148 //config: depends on HUSH
150 //config: Enable interactive mode (prompt and command editing).
151 //config: Without this, hush simply reads and executes commands
152 //config: from stdin just like a shell script from a file.
153 //config: No prompt, no PS1/PS2 magic shell variables.
155 //config:config HUSH_SAVEHISTORY
156 //config: bool "Save command history to .hush_history"
158 //config: depends on HUSH_INTERACTIVE && FEATURE_EDITING_SAVEHISTORY
160 //config: Enable history saving in hush.
162 //config:config HUSH_JOB
163 //config: bool "Job control"
165 //config: depends on HUSH_INTERACTIVE
167 //config: Enable job control: Ctrl-Z backgrounds, Ctrl-C interrupts current
168 //config: command (not entire shell), fg/bg builtins work. Without this option,
169 //config: "cmd &" still works by simply spawning a process and immediately
170 //config: prompting for next command (or executing next command in a script),
171 //config: but no separate process group is formed.
173 //config:config HUSH_TICK
174 //config: bool "Process substitution"
176 //config: depends on HUSH
178 //config: Enable process substitution `command` and $(command) in hush.
180 //config:config HUSH_IF
181 //config: bool "Support if/then/elif/else/fi"
183 //config: depends on HUSH
185 //config: Enable if/then/elif/else/fi in hush.
187 //config:config HUSH_LOOPS
188 //config: bool "Support for, while and until loops"
190 //config: depends on HUSH
192 //config: Enable for, while and until loops in hush.
194 //config:config HUSH_CASE
195 //config: bool "Support case ... esac statement"
197 //config: depends on HUSH
199 //config: Enable case ... esac statement in hush. +400 bytes.
201 //config:config HUSH_FUNCTIONS
202 //config: bool "Support funcname() { commands; } syntax"
204 //config: depends on HUSH
206 //config: Enable support for shell functions in hush. +800 bytes.
208 //config:config HUSH_LOCAL
209 //config: bool "Support local builtin"
211 //config: depends on HUSH_FUNCTIONS
213 //config: Enable support for local variables in functions.
215 //config:config HUSH_RANDOM_SUPPORT
216 //config: bool "Pseudorandom generator and $RANDOM variable"
218 //config: depends on HUSH
220 //config: Enable pseudorandom generator and dynamic variable "$RANDOM".
221 //config: Each read of "$RANDOM" will generate a new pseudorandom value.
223 //config:config HUSH_EXPORT_N
224 //config: bool "Support 'export -n' option"
226 //config: depends on HUSH
228 //config: export -n unexports variables. It is a bash extension.
230 //config:config HUSH_MODE_X
231 //config: bool "Support 'hush -x' option and 'set -x' command"
233 //config: depends on HUSH
235 //config: This instructs hush to print commands before execution.
236 //config: Adds ~300 bytes.
239 //config: bool "msh (deprecated: aliased to hush)"
241 //config: select HUSH
243 //config: msh is deprecated and will be removed, please migrate to hush.
246 //applet:IF_HUSH(APPLET(hush, BB_DIR_BIN, BB_SUID_DROP))
247 //applet:IF_MSH(APPLET(msh, BB_DIR_BIN, BB_SUID_DROP))
248 //applet:IF_FEATURE_SH_IS_HUSH(APPLET_ODDNAME(sh, hush, BB_DIR_BIN, BB_SUID_DROP, sh))
249 //applet:IF_FEATURE_BASH_IS_HUSH(APPLET_ODDNAME(bash, hush, BB_DIR_BIN, BB_SUID_DROP, bash))
251 //kbuild:lib-$(CONFIG_HUSH) += hush.o match.o shell_common.o
252 //kbuild:lib-$(CONFIG_HUSH_RANDOM_SUPPORT) += random.o
254 /* -i (interactive) and -s (read stdin) are also accepted,
255 * but currently do nothing, therefore aren't shown in help.
256 * NOMMU-specific options are not meant to be used by users,
257 * therefore we don't show them either.
259 //usage:#define hush_trivial_usage
260 //usage: "[-nxl] [-c 'SCRIPT' [ARG0 [ARGS]] / FILE [ARGS]]"
261 //usage:#define hush_full_usage "\n\n"
262 //usage: "Unix shell interpreter"
264 //usage:#define msh_trivial_usage hush_trivial_usage
265 //usage:#define msh_full_usage hush_full_usage
267 //usage:#if ENABLE_FEATURE_SH_IS_HUSH
268 //usage:# define sh_trivial_usage hush_trivial_usage
269 //usage:# define sh_full_usage hush_full_usage
271 //usage:#if ENABLE_FEATURE_BASH_IS_HUSH
272 //usage:# define bash_trivial_usage hush_trivial_usage
273 //usage:# define bash_full_usage hush_full_usage
278 #define LEAK_HUNTING 0
279 #define BUILD_AS_NOMMU 0
280 /* Enable/disable sanity checks. Ok to enable in production,
281 * only adds a bit of bloat. Set to >1 to get non-production level verbosity.
282 * Keeping 1 for now even in released versions.
285 /* Slightly bigger (+200 bytes), but faster hush.
286 * So far it only enables a trick with counting SIGCHLDs and forks,
287 * which allows us to do fewer waitpid's.
288 * (we can detect a case where neither forks were done nor SIGCHLDs happened
289 * and therefore waitpid will return the same result as last time)
291 #define ENABLE_HUSH_FAST 0
292 /* TODO: implement simplified code for users which do not need ${var%...} ops
293 * So far ${var%...} ops are always enabled:
295 #define ENABLE_HUSH_DOLLAR_OPS 1
300 # undef USE_FOR_NOMMU
303 # define USE_FOR_NOMMU(...) __VA_ARGS__
304 # define USE_FOR_MMU(...)
307 #include "NUM_APPLETS.h"
309 /* STANDALONE does not make sense, and won't compile */
310 # undef CONFIG_FEATURE_SH_STANDALONE
311 # undef ENABLE_FEATURE_SH_STANDALONE
312 # undef IF_FEATURE_SH_STANDALONE
313 # undef IF_NOT_FEATURE_SH_STANDALONE
314 # define ENABLE_FEATURE_SH_STANDALONE 0
315 # define IF_FEATURE_SH_STANDALONE(...)
316 # define IF_NOT_FEATURE_SH_STANDALONE(...) __VA_ARGS__
319 #if !ENABLE_HUSH_INTERACTIVE
320 # undef ENABLE_FEATURE_EDITING
321 # define ENABLE_FEATURE_EDITING 0
322 # undef ENABLE_FEATURE_EDITING_FANCY_PROMPT
323 # define ENABLE_FEATURE_EDITING_FANCY_PROMPT 0
324 # undef ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
325 # define ENABLE_FEATURE_EDITING_SAVE_ON_EXIT 0
328 /* Do we support ANY keywords? */
329 #if ENABLE_HUSH_IF || ENABLE_HUSH_LOOPS || ENABLE_HUSH_CASE
330 # define HAS_KEYWORDS 1
331 # define IF_HAS_KEYWORDS(...) __VA_ARGS__
332 # define IF_HAS_NO_KEYWORDS(...)
334 # define HAS_KEYWORDS 0
335 # define IF_HAS_KEYWORDS(...)
336 # define IF_HAS_NO_KEYWORDS(...) __VA_ARGS__
339 /* If you comment out one of these below, it will be #defined later
340 * to perform debug printfs to stderr: */
341 #define debug_printf(...) do {} while (0)
342 /* Finer-grained debug switches */
343 #define debug_printf_parse(...) do {} while (0)
344 #define debug_print_tree(a, b) do {} while (0)
345 #define debug_printf_exec(...) do {} while (0)
346 #define debug_printf_env(...) do {} while (0)
347 #define debug_printf_jobs(...) do {} while (0)
348 #define debug_printf_expand(...) do {} while (0)
349 #define debug_printf_varexp(...) do {} while (0)
350 #define debug_printf_glob(...) do {} while (0)
351 #define debug_printf_list(...) do {} while (0)
352 #define debug_printf_subst(...) do {} while (0)
353 #define debug_printf_clean(...) do {} while (0)
355 #define ERR_PTR ((void*)(long)1)
357 #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
359 #define _SPECIAL_VARS_STR "_*@$!?#"
360 #define SPECIAL_VARS_STR ("_*@$!?#" + 1)
361 #define NUMERIC_SPECVARS_STR ("_*@$!?#" + 3)
362 #if ENABLE_HUSH_BASH_COMPAT
363 /* Support / and // replace ops */
364 /* Note that // is stored as \ in "encoded" string representation */
365 # define VAR_ENCODED_SUBST_OPS "\\/%#:-=+?"
366 # define VAR_SUBST_OPS ("\\/%#:-=+?" + 1)
367 # define MINUS_PLUS_EQUAL_QUESTION ("\\/%#:-=+?" + 5)
369 # define VAR_ENCODED_SUBST_OPS "%#:-=+?"
370 # define VAR_SUBST_OPS "%#:-=+?"
371 # define MINUS_PLUS_EQUAL_QUESTION ("%#:-=+?" + 3)
374 #define SPECIAL_VAR_SYMBOL 3
378 static const char hush_version_str[] ALIGN1 = "HUSH_VERSION="BB_VER;
380 /* This supports saving pointers malloced in vfork child,
381 * to be freed in the parent.
384 typedef struct nommu_save_t {
386 struct variable *old_vars;
388 char **argv_from_re_execing;
401 #if ENABLE_HUSH_LOOPS
408 #if ENABLE_HUSH_LOOPS || ENABLE_HUSH_CASE
413 /* three pseudo-keywords support contrived "case" syntax: */
414 RES_CASE_IN, /* "case ... IN", turns into RES_MATCH when IN is observed */
415 RES_MATCH , /* "word)" */
416 RES_CASE_BODY, /* "this command is inside CASE" */
423 typedef struct o_string {
425 int length; /* position where data is appended */
428 /* At least some part of the string was inside '' or "",
429 * possibly empty one: word"", wo''rd etc. */
430 smallint has_quoted_part;
431 smallint has_empty_slot;
432 smallint o_assignment; /* 0:maybe, 1:yes, 2:no */
435 EXP_FLAG_SINGLEWORD = 0x80, /* must be 0x80 */
437 /* Protect newly added chars against globbing
438 * by prepending \ to *, ?, [, \ */
439 EXP_FLAG_ESC_GLOB_CHARS = 0x1,
442 MAYBE_ASSIGNMENT = 0,
443 DEFINITELY_ASSIGNMENT = 1,
445 /* Not an assigment, but next word may be: "if v=xyz cmd;" */
448 /* Used for initialization: o_string foo = NULL_O_STRING; */
449 #define NULL_O_STRING { NULL }
451 #ifndef debug_printf_parse
452 static const char *const assignment_flag[] = {
454 "DEFINITELY_ASSIGNMENT",
460 typedef struct in_str {
462 /* eof_flag=1: last char in ->p is really an EOF */
463 char eof_flag; /* meaningless if ->p == NULL */
465 #if ENABLE_HUSH_INTERACTIVE
466 smallint promptmode; /* 0: PS1, 1: PS2 */
470 int (*get) (struct in_str *) FAST_FUNC;
471 int (*peek) (struct in_str *) FAST_FUNC;
473 #define i_getch(input) ((input)->get(input))
474 #define i_peek(input) ((input)->peek(input))
476 /* The descrip member of this structure is only used to make
477 * debugging output pretty */
478 static const struct {
480 signed char default_fd;
483 { O_RDONLY, 0, "<" },
484 { O_CREAT|O_TRUNC|O_WRONLY, 1, ">" },
485 { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
486 { O_CREAT|O_RDWR, 1, "<>" },
487 { O_RDONLY, 0, "<<" },
488 /* Should not be needed. Bogus default_fd helps in debugging */
489 /* { O_RDONLY, 77, "<<" }, */
492 struct redir_struct {
493 struct redir_struct *next;
494 char *rd_filename; /* filename */
495 int rd_fd; /* fd to redirect */
496 /* fd to redirect to, or -3 if rd_fd is to be closed (n>&-) */
498 smallint rd_type; /* (enum redir_type) */
499 /* note: for heredocs, rd_filename contains heredoc delimiter,
500 * and subsequently heredoc itself; and rd_dup is a bitmask:
501 * bit 0: do we need to trim leading tabs?
502 * bit 1: is heredoc quoted (<<'delim' syntax) ?
505 typedef enum redir_type {
507 REDIRECT_OVERWRITE = 1,
510 REDIRECT_HEREDOC = 4,
511 REDIRECT_HEREDOC2 = 5, /* REDIRECT_HEREDOC after heredoc is loaded */
514 REDIRFD_SYNTAX_ERR = -2,
515 REDIRFD_TO_FILE = -1,
516 /* otherwise, rd_fd is redirected to rd_dup */
518 HEREDOC_SKIPTABS = 1,
524 pid_t pid; /* 0 if exited */
525 int assignment_cnt; /* how many argv[i] are assignments? */
526 smallint cmd_type; /* CMD_xxx */
528 #define CMD_SUBSHELL 1
529 #if ENABLE_HUSH_BASH_COMPAT
530 /* used for "[[ EXPR ]]" */
531 # define CMD_SINGLEWORD_NOGLOB 2
533 #if ENABLE_HUSH_FUNCTIONS
534 # define CMD_FUNCDEF 3
537 smalluint cmd_exitcode;
538 /* if non-NULL, this "command" is { list }, ( list ), or a compound statement */
541 char *group_as_string;
543 #if ENABLE_HUSH_FUNCTIONS
544 struct function *child_func;
545 /* This field is used to prevent a bug here:
546 * while...do f1() {a;}; f1; f1() {b;}; f1; done
547 * When we execute "f1() {a;}" cmd, we create new function and clear
548 * cmd->group, cmd->group_as_string, cmd->argv[0].
549 * When we execute "f1() {b;}", we notice that f1 exists,
550 * and that its "parent cmd" struct is still "alive",
551 * we put those fields back into cmd->xxx
552 * (struct function has ->parent_cmd ptr to facilitate that).
553 * When we loop back, we can execute "f1() {a;}" again and set f1 correctly.
554 * Without this trick, loop would execute a;b;b;b;...
555 * instead of correct sequence a;b;a;b;...
556 * When command is freed, it severs the link
557 * (sets ->child_func->parent_cmd to NULL).
560 char **argv; /* command name and arguments */
561 /* argv vector may contain variable references (^Cvar^C, ^C0^C etc)
562 * and on execution these are substituted with their values.
563 * Substitution can make _several_ words out of one argv[n]!
564 * Example: argv[0]=='.^C*^C.' here: echo .$*.
565 * References of the form ^C`cmd arg^C are `cmd arg` substitutions.
567 struct redir_struct *redirects; /* I/O redirections */
569 /* Is there anything in this command at all? */
570 #define IS_NULL_CMD(cmd) \
571 (!(cmd)->group && !(cmd)->argv && !(cmd)->redirects)
575 int num_cmds; /* total number of commands in pipe */
576 int alive_cmds; /* number of commands running (not exited) */
577 int stopped_cmds; /* number of commands alive, but stopped */
579 int jobid; /* job number */
580 pid_t pgrp; /* process group ID for the job */
581 char *cmdtext; /* name of job */
583 struct command *cmds; /* array of commands in pipe */
584 smallint followup; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
585 IF_HAS_KEYWORDS(smallint pi_inverted;) /* "! cmd | cmd" */
586 IF_HAS_KEYWORDS(smallint res_word;) /* needed for if, for, while, until... */
588 typedef enum pipe_style {
594 /* Is there anything in this pipe at all? */
595 #define IS_NULL_PIPE(pi) \
596 ((pi)->num_cmds == 0 IF_HAS_KEYWORDS( && (pi)->res_word == RES_NONE))
598 /* This holds pointers to the various results of parsing */
599 struct parse_context {
600 /* linked list of pipes */
601 struct pipe *list_head;
602 /* last pipe (being constructed right now) */
604 /* last command in pipe (being constructed right now) */
605 struct command *command;
606 /* last redirect in command->redirects list */
607 struct redir_struct *pending_redirect;
613 smallint ctx_inverted; /* "! cmd | cmd" */
615 smallint ctx_dsemicolon; /* ";;" seen */
617 /* bitmask of FLAG_xxx, for figuring out valid reserved words */
619 /* group we are enclosed in:
620 * example: "if pipe1; pipe2; then pipe3; fi"
621 * when we see "if" or "then", we malloc and copy current context,
622 * and make ->stack point to it. then we parse pipeN.
623 * when closing "then" / fi" / whatever is found,
624 * we move list_head into ->stack->command->group,
625 * copy ->stack into current context, and delete ->stack.
626 * (parsing of { list } and ( list ) doesn't use this method)
628 struct parse_context *stack;
632 /* On program start, environ points to initial environment.
633 * putenv adds new pointers into it, unsetenv removes them.
634 * Neither of these (de)allocates the strings.
635 * setenv allocates new strings in malloc space and does putenv,
636 * and thus setenv is unusable (leaky) for shell's purposes */
637 #define setenv(...) setenv_is_leaky_dont_use()
639 struct variable *next;
640 char *varstr; /* points to "name=" portion */
641 #if ENABLE_HUSH_LOCAL
642 unsigned func_nest_level;
644 int max_len; /* if > 0, name is part of initial env; else name is malloced */
645 smallint flg_export; /* putenv should be done on this var */
646 smallint flg_read_only;
654 #if ENABLE_HUSH_FUNCTIONS
656 struct function *next;
658 struct command *parent_cmd;
661 char *body_as_string;
667 /* set -/+o OPT support. (TODO: make it optional)
668 * bash supports the following opts:
679 * interactive-comments on
697 static const char o_opt_strings[] ALIGN1 =
700 #if ENABLE_HUSH_MODE_X
707 #if ENABLE_HUSH_MODE_X
714 /* "Globals" within this file */
715 /* Sorted roughly by size (smaller offsets == smaller code) */
717 /* interactive_fd != 0 means we are an interactive shell.
718 * If we are, then saved_tty_pgrp can also be != 0, meaning
719 * that controlling tty is available. With saved_tty_pgrp == 0,
720 * job control still works, but terminal signals
721 * (^C, ^Z, ^Y, ^\) won't work at all, and background
722 * process groups can only be created with "cmd &".
723 * With saved_tty_pgrp != 0, hush will use tcsetpgrp()
724 * to give tty to the foreground process group,
725 * and will take it back when the group is stopped (^Z)
728 #if ENABLE_HUSH_INTERACTIVE
729 /* 'interactive_fd' is a fd# open to ctty, if we have one
730 * _AND_ if we decided to act interactively */
734 # define G_interactive_fd (G.interactive_fd)
736 # define G_interactive_fd 0
738 #if ENABLE_FEATURE_EDITING
739 line_input_t *line_input_state;
744 #if ENABLE_HUSH_RANDOM_SUPPORT
750 pid_t saved_tty_pgrp;
751 struct pipe *job_list;
752 # define G_saved_tty_pgrp (G.saved_tty_pgrp)
754 # define G_saved_tty_pgrp 0
756 char o_opt[NUM_OPT_O];
757 #if ENABLE_HUSH_MODE_X
758 # define G_x_mode (G.o_opt[OPT_O_XTRACE])
762 smallint flag_SIGINT;
763 #if ENABLE_HUSH_LOOPS
764 smallint flag_break_continue;
766 #if ENABLE_HUSH_FUNCTIONS
767 /* 0: outside of a function (or sourced file)
768 * -1: inside of a function, ok to use return builtin
769 * 1: return is invoked, skip all till end of func
771 smallint flag_return_in_progress;
773 smallint exiting; /* used to prevent EXIT trap recursion */
774 /* These four support $?, $#, and $1 */
775 smalluint last_exitcode;
776 /* are global_argv and global_argv[1..n] malloced? (note: not [0]) */
777 smalluint global_args_malloced;
778 /* how many non-NULL argv's we have. NB: $# + 1 */
782 char *argv0_for_re_execing;
784 #if ENABLE_HUSH_LOOPS
785 unsigned depth_break_continue;
786 unsigned depth_of_loop;
790 struct variable *top_var;
791 char **expanded_assignments;
792 #if ENABLE_HUSH_FUNCTIONS
793 struct function *top_func;
794 # if ENABLE_HUSH_LOCAL
795 struct variable **shadowed_vars_pp;
796 unsigned func_nest_level;
799 /* Signal and trap handling */
801 unsigned count_SIGCHLD;
802 unsigned handled_SIGCHLD;
803 smallint we_have_children;
805 /* Which signals have non-DFL handler (even with no traps set)?
806 * Set at the start to:
807 * (SIGQUIT + maybe SPECIAL_INTERACTIVE_SIGS + maybe SPECIAL_JOBSTOP_SIGS)
808 * SPECIAL_INTERACTIVE_SIGS are cleared after fork.
809 * The rest is cleared right before execv syscalls.
810 * Other than these two times, never modified.
812 unsigned special_sig_mask;
814 unsigned fatal_sig_mask;
815 # define G_fatal_sig_mask G.fatal_sig_mask
817 # define G_fatal_sig_mask 0
819 char **traps; /* char *traps[NSIG] */
820 sigset_t pending_set;
822 unsigned long memleak_value;
826 char user_input_buf[ENABLE_FEATURE_EDITING ? CONFIG_FEATURE_EDITING_MAX_LEN : 2];
828 #define G (*ptr_to_globals)
829 /* Not #defining name to G.name - this quickly gets unwieldy
830 * (too many defines). Also, I actually prefer to see when a variable
831 * is global, thus "G." prefix is a useful hint */
832 #define INIT_G() do { \
833 SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
834 /* memset(&G.sa, 0, sizeof(G.sa)); */ \
835 sigfillset(&G.sa.sa_mask); \
836 G.sa.sa_flags = SA_RESTART; \
840 /* Function prototypes for builtins */
841 static int builtin_cd(char **argv) FAST_FUNC;
842 static int builtin_echo(char **argv) FAST_FUNC;
843 static int builtin_eval(char **argv) FAST_FUNC;
844 static int builtin_exec(char **argv) FAST_FUNC;
845 static int builtin_exit(char **argv) FAST_FUNC;
846 static int builtin_export(char **argv) FAST_FUNC;
848 static int builtin_fg_bg(char **argv) FAST_FUNC;
849 static int builtin_jobs(char **argv) FAST_FUNC;
852 static int builtin_help(char **argv) FAST_FUNC;
854 #if MAX_HISTORY && ENABLE_FEATURE_EDITING
855 static int builtin_history(char **argv) FAST_FUNC;
857 #if ENABLE_HUSH_LOCAL
858 static int builtin_local(char **argv) FAST_FUNC;
861 static int builtin_memleak(char **argv) FAST_FUNC;
864 static int builtin_printf(char **argv) FAST_FUNC;
866 static int builtin_pwd(char **argv) FAST_FUNC;
867 static int builtin_read(char **argv) FAST_FUNC;
868 static int builtin_set(char **argv) FAST_FUNC;
869 static int builtin_shift(char **argv) FAST_FUNC;
870 static int builtin_source(char **argv) FAST_FUNC;
871 static int builtin_test(char **argv) FAST_FUNC;
872 static int builtin_trap(char **argv) FAST_FUNC;
873 static int builtin_type(char **argv) FAST_FUNC;
874 static int builtin_true(char **argv) FAST_FUNC;
875 static int builtin_umask(char **argv) FAST_FUNC;
876 static int builtin_unset(char **argv) FAST_FUNC;
877 static int builtin_wait(char **argv) FAST_FUNC;
878 #if ENABLE_HUSH_LOOPS
879 static int builtin_break(char **argv) FAST_FUNC;
880 static int builtin_continue(char **argv) FAST_FUNC;
882 #if ENABLE_HUSH_FUNCTIONS
883 static int builtin_return(char **argv) FAST_FUNC;
886 /* Table of built-in functions. They can be forked or not, depending on
887 * context: within pipes, they fork. As simple commands, they do not.
888 * When used in non-forking context, they can change global variables
889 * in the parent shell process. If forked, of course they cannot.
890 * For example, 'unset foo | whatever' will parse and run, but foo will
891 * still be set at the end. */
892 struct built_in_command {
894 int (*b_function)(char **argv) FAST_FUNC;
897 # define BLTIN(cmd, func, help) { cmd, func, help }
899 # define BLTIN(cmd, func, help) { cmd, func }
903 static const struct built_in_command bltins1[] = {
904 BLTIN("." , builtin_source , "Run commands in a file"),
905 BLTIN(":" , builtin_true , NULL),
907 BLTIN("bg" , builtin_fg_bg , "Resume a job in the background"),
909 #if ENABLE_HUSH_LOOPS
910 BLTIN("break" , builtin_break , "Exit from a loop"),
912 BLTIN("cd" , builtin_cd , "Change directory"),
913 #if ENABLE_HUSH_LOOPS
914 BLTIN("continue" , builtin_continue, "Start new loop iteration"),
916 BLTIN("eval" , builtin_eval , "Construct and run shell command"),
917 BLTIN("exec" , builtin_exec , "Execute command, don't return to shell"),
918 BLTIN("exit" , builtin_exit , "Exit"),
919 BLTIN("export" , builtin_export , "Set environment variables"),
921 BLTIN("fg" , builtin_fg_bg , "Bring job into the foreground"),
924 BLTIN("help" , builtin_help , NULL),
926 #if MAX_HISTORY && ENABLE_FEATURE_EDITING
927 BLTIN("history" , builtin_history , "Show command history"),
930 BLTIN("jobs" , builtin_jobs , "List jobs"),
932 #if ENABLE_HUSH_LOCAL
933 BLTIN("local" , builtin_local , "Set local variables"),
936 BLTIN("memleak" , builtin_memleak , NULL),
938 BLTIN("read" , builtin_read , "Input into variable"),
939 #if ENABLE_HUSH_FUNCTIONS
940 BLTIN("return" , builtin_return , "Return from a function"),
942 BLTIN("set" , builtin_set , "Set/unset positional parameters"),
943 BLTIN("shift" , builtin_shift , "Shift positional parameters"),
944 #if ENABLE_HUSH_BASH_COMPAT
945 BLTIN("source" , builtin_source , "Run commands in a file"),
947 BLTIN("trap" , builtin_trap , "Trap signals"),
948 BLTIN("true" , builtin_true , NULL),
949 BLTIN("type" , builtin_type , "Show command type"),
950 BLTIN("ulimit" , shell_builtin_ulimit , "Control resource limits"),
951 BLTIN("umask" , builtin_umask , "Set file creation mask"),
952 BLTIN("unset" , builtin_unset , "Unset variables"),
953 BLTIN("wait" , builtin_wait , "Wait for process"),
955 /* For now, echo and test are unconditionally enabled.
956 * Maybe make it configurable? */
957 static const struct built_in_command bltins2[] = {
958 BLTIN("[" , builtin_test , NULL),
959 BLTIN("echo" , builtin_echo , NULL),
961 BLTIN("printf" , builtin_printf , NULL),
963 BLTIN("pwd" , builtin_pwd , NULL),
964 BLTIN("test" , builtin_test , NULL),
971 /* prevent disasters with G.debug_indent < 0 */
972 # define indent() fdprintf(2, "%*s", (G.debug_indent * 2) & 0xff, "")
973 # define debug_enter() (G.debug_indent++)
974 # define debug_leave() (G.debug_indent--)
976 # define indent() ((void)0)
977 # define debug_enter() ((void)0)
978 # define debug_leave() ((void)0)
982 # define debug_printf(...) (indent(), fdprintf(2, __VA_ARGS__))
985 #ifndef debug_printf_parse
986 # define debug_printf_parse(...) (indent(), fdprintf(2, __VA_ARGS__))
989 #ifndef debug_printf_exec
990 #define debug_printf_exec(...) (indent(), fdprintf(2, __VA_ARGS__))
993 #ifndef debug_printf_env
994 # define debug_printf_env(...) (indent(), fdprintf(2, __VA_ARGS__))
997 #ifndef debug_printf_jobs
998 # define debug_printf_jobs(...) (indent(), fdprintf(2, __VA_ARGS__))
999 # define DEBUG_JOBS 1
1001 # define DEBUG_JOBS 0
1004 #ifndef debug_printf_expand
1005 # define debug_printf_expand(...) (indent(), fdprintf(2, __VA_ARGS__))
1006 # define DEBUG_EXPAND 1
1008 # define DEBUG_EXPAND 0
1011 #ifndef debug_printf_varexp
1012 # define debug_printf_varexp(...) (indent(), fdprintf(2, __VA_ARGS__))
1015 #ifndef debug_printf_glob
1016 # define debug_printf_glob(...) (indent(), fdprintf(2, __VA_ARGS__))
1017 # define DEBUG_GLOB 1
1019 # define DEBUG_GLOB 0
1022 #ifndef debug_printf_list
1023 # define debug_printf_list(...) (indent(), fdprintf(2, __VA_ARGS__))
1026 #ifndef debug_printf_subst
1027 # define debug_printf_subst(...) (indent(), fdprintf(2, __VA_ARGS__))
1030 #ifndef debug_printf_clean
1031 # define debug_printf_clean(...) (indent(), fdprintf(2, __VA_ARGS__))
1032 # define DEBUG_CLEAN 1
1034 # define DEBUG_CLEAN 0
1038 static void debug_print_strings(const char *prefix, char **vv)
1041 fdprintf(2, "%s:\n", prefix);
1043 fdprintf(2, " '%s'\n", *vv++);
1046 # define debug_print_strings(prefix, vv) ((void)0)
1050 /* Leak hunting. Use hush_leaktool.sh for post-processing.
1053 static void *xxmalloc(int lineno, size_t size)
1055 void *ptr = xmalloc((size + 0xff) & ~0xff);
1056 fdprintf(2, "line %d: malloc %p\n", lineno, ptr);
1059 static void *xxrealloc(int lineno, void *ptr, size_t size)
1061 ptr = xrealloc(ptr, (size + 0xff) & ~0xff);
1062 fdprintf(2, "line %d: realloc %p\n", lineno, ptr);
1065 static char *xxstrdup(int lineno, const char *str)
1067 char *ptr = xstrdup(str);
1068 fdprintf(2, "line %d: strdup %p\n", lineno, ptr);
1071 static void xxfree(void *ptr)
1073 fdprintf(2, "free %p\n", ptr);
1076 # define xmalloc(s) xxmalloc(__LINE__, s)
1077 # define xrealloc(p, s) xxrealloc(__LINE__, p, s)
1078 # define xstrdup(s) xxstrdup(__LINE__, s)
1079 # define free(p) xxfree(p)
1083 /* Syntax and runtime errors. They always abort scripts.
1084 * In interactive use they usually discard unparsed and/or unexecuted commands
1085 * and return to the prompt.
1086 * HUSH_DEBUG >= 2 prints line number in this file where it was detected.
1089 # define die_if_script(lineno, ...) die_if_script(__VA_ARGS__)
1090 # define syntax_error(lineno, msg) syntax_error(msg)
1091 # define syntax_error_at(lineno, msg) syntax_error_at(msg)
1092 # define syntax_error_unterm_ch(lineno, ch) syntax_error_unterm_ch(ch)
1093 # define syntax_error_unterm_str(lineno, s) syntax_error_unterm_str(s)
1094 # define syntax_error_unexpected_ch(lineno, ch) syntax_error_unexpected_ch(ch)
1097 static void die_if_script(unsigned lineno, const char *fmt, ...)
1102 bb_error_msg("hush.c:%u", lineno);
1105 bb_verror_msg(fmt, p, NULL);
1107 if (!G_interactive_fd)
1111 static void syntax_error(unsigned lineno UNUSED_PARAM, const char *msg)
1114 bb_error_msg("syntax error: %s", msg);
1116 bb_error_msg("syntax error");
1119 static void syntax_error_at(unsigned lineno UNUSED_PARAM, const char *msg)
1121 bb_error_msg("syntax error at '%s'", msg);
1124 static void syntax_error_unterm_str(unsigned lineno UNUSED_PARAM, const char *s)
1126 bb_error_msg("syntax error: unterminated %s", s);
1129 static void syntax_error_unterm_ch(unsigned lineno, char ch)
1131 char msg[2] = { ch, '\0' };
1132 syntax_error_unterm_str(lineno, msg);
1135 static void syntax_error_unexpected_ch(unsigned lineno UNUSED_PARAM, int ch)
1140 bb_error_msg("syntax error: unexpected %s", ch == EOF ? "EOF" : msg);
1144 # undef die_if_script
1145 # undef syntax_error
1146 # undef syntax_error_at
1147 # undef syntax_error_unterm_ch
1148 # undef syntax_error_unterm_str
1149 # undef syntax_error_unexpected_ch
1151 # define die_if_script(...) die_if_script(__LINE__, __VA_ARGS__)
1152 # define syntax_error(msg) syntax_error(__LINE__, msg)
1153 # define syntax_error_at(msg) syntax_error_at(__LINE__, msg)
1154 # define syntax_error_unterm_ch(ch) syntax_error_unterm_ch(__LINE__, ch)
1155 # define syntax_error_unterm_str(s) syntax_error_unterm_str(__LINE__, s)
1156 # define syntax_error_unexpected_ch(ch) syntax_error_unexpected_ch(__LINE__, ch)
1160 #if ENABLE_HUSH_INTERACTIVE
1161 static void cmdedit_update_prompt(void);
1163 # define cmdedit_update_prompt() ((void)0)
1167 /* Utility functions
1169 /* Replace each \x with x in place, return ptr past NUL. */
1170 static char *unbackslash(char *src)
1172 char *dst = src = strchrnul(src, '\\');
1176 if ((*dst++ = *src++) == '\0')
1182 static char **add_strings_to_strings(char **strings, char **add, int need_to_dup)
1203 v = xrealloc(strings, (count1 + count2 + 1) * sizeof(char*));
1204 v[count1 + count2] = NULL;
1207 v[count1 + i] = (need_to_dup ? xstrdup(add[i]) : add[i]);
1211 static char **xx_add_strings_to_strings(int lineno, char **strings, char **add, int need_to_dup)
1213 char **ptr = add_strings_to_strings(strings, add, need_to_dup);
1214 fdprintf(2, "line %d: add_strings_to_strings %p\n", lineno, ptr);
1217 #define add_strings_to_strings(strings, add, need_to_dup) \
1218 xx_add_strings_to_strings(__LINE__, strings, add, need_to_dup)
1221 /* Note: takes ownership of "add" ptr (it is not strdup'ed) */
1222 static char **add_string_to_strings(char **strings, char *add)
1227 return add_strings_to_strings(strings, v, /*dup:*/ 0);
1230 static char **xx_add_string_to_strings(int lineno, char **strings, char *add)
1232 char **ptr = add_string_to_strings(strings, add);
1233 fdprintf(2, "line %d: add_string_to_strings %p\n", lineno, ptr);
1236 #define add_string_to_strings(strings, add) \
1237 xx_add_string_to_strings(__LINE__, strings, add)
1240 static void free_strings(char **strings)
1255 /* Helpers for setting new $n and restoring them back
1257 typedef struct save_arg_t {
1261 smallint sv_g_malloced;
1264 static void save_and_replace_G_args(save_arg_t *sv, char **argv)
1268 sv->sv_argv0 = argv[0];
1269 sv->sv_g_argv = G.global_argv;
1270 sv->sv_g_argc = G.global_argc;
1271 sv->sv_g_malloced = G.global_args_malloced;
1273 argv[0] = G.global_argv[0]; /* retain $0 */
1274 G.global_argv = argv;
1275 G.global_args_malloced = 0;
1283 static void restore_G_args(save_arg_t *sv, char **argv)
1287 if (G.global_args_malloced) {
1288 /* someone ran "set -- arg1 arg2 ...", undo */
1290 while (*++pp) /* note: does not free $0 */
1292 free(G.global_argv);
1294 argv[0] = sv->sv_argv0;
1295 G.global_argv = sv->sv_g_argv;
1296 G.global_argc = sv->sv_g_argc;
1297 G.global_args_malloced = sv->sv_g_malloced;
1301 /* Basic theory of signal handling in shell
1302 * ========================================
1303 * This does not describe what hush does, rather, it is current understanding
1304 * what it _should_ do. If it doesn't, it's a bug.
1305 * http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#trap
1307 * Signals are handled only after each pipe ("cmd | cmd | cmd" thing)
1308 * is finished or backgrounded. It is the same in interactive and
1309 * non-interactive shells, and is the same regardless of whether
1310 * a user trap handler is installed or a shell special one is in effect.
1311 * ^C or ^Z from keyboard seems to execute "at once" because it usually
1312 * backgrounds (i.e. stops) or kills all members of currently running
1315 * Wait builtin is interruptible by signals for which user trap is set
1316 * or by SIGINT in interactive shell.
1318 * Trap handlers will execute even within trap handlers. (right?)
1320 * User trap handlers are forgotten when subshell ("(cmd)") is entered,
1321 * except for handlers set to '' (empty string).
1323 * If job control is off, backgrounded commands ("cmd &")
1324 * have SIGINT, SIGQUIT set to SIG_IGN.
1326 * Commands which are run in command substitution ("`cmd`")
1327 * have SIGTTIN, SIGTTOU, SIGTSTP set to SIG_IGN.
1329 * Ordinary commands have signals set to SIG_IGN/DFL as inherited
1330 * by the shell from its parent.
1332 * Signals which differ from SIG_DFL action
1333 * (note: child (i.e., [v]forked) shell is not an interactive shell):
1336 * SIGTERM (interactive): ignore
1337 * SIGHUP (interactive):
1338 * send SIGCONT to stopped jobs, send SIGHUP to all jobs and exit
1339 * SIGTTIN, SIGTTOU, SIGTSTP (if job control is on): ignore
1340 * Note that ^Z is handled not by trapping SIGTSTP, but by seeing
1341 * that all pipe members are stopped. Try this in bash:
1342 * while :; do :; done - ^Z does not background it
1343 * (while :; do :; done) - ^Z backgrounds it
1344 * SIGINT (interactive): wait for last pipe, ignore the rest
1345 * of the command line, show prompt. NB: ^C does not send SIGINT
1346 * to interactive shell while shell is waiting for a pipe,
1347 * since shell is bg'ed (is not in foreground process group).
1348 * Example 1: this waits 5 sec, but does not execute ls:
1349 * "echo $$; sleep 5; ls -l" + "kill -INT <pid>"
1350 * Example 2: this does not wait and does not execute ls:
1351 * "echo $$; sleep 5 & wait; ls -l" + "kill -INT <pid>"
1352 * Example 3: this does not wait 5 sec, but executes ls:
1353 * "sleep 5; ls -l" + press ^C
1354 * Example 4: this does not wait and does not execute ls:
1355 * "sleep 5 & wait; ls -l" + press ^C
1357 * (What happens to signals which are IGN on shell start?)
1358 * (What happens with signal mask on shell start?)
1360 * Old implementation
1361 * ==================
1362 * We use in-kernel pending signal mask to determine which signals were sent.
1363 * We block all signals which we don't want to take action immediately,
1364 * i.e. we block all signals which need to have special handling as described
1365 * above, and all signals which have traps set.
1366 * After each pipe execution, we extract any pending signals via sigtimedwait()
1369 * unsigned special_sig_mask: a mask of such "special" signals
1370 * sigset_t blocked_set: current blocked signal set
1373 * clear bit in blocked_set unless it is also in special_sig_mask
1374 * "trap 'cmd' SIGxxx":
1375 * set bit in blocked_set (even if 'cmd' is '')
1376 * after [v]fork, if we plan to be a shell:
1377 * unblock signals with special interactive handling
1378 * (child shell is not interactive),
1379 * unset all traps except '' (note: regardless of child shell's type - {}, (), etc)
1380 * after [v]fork, if we plan to exec:
1381 * POSIX says fork clears pending signal mask in child - no need to clear it.
1382 * Restore blocked signal set to one inherited by shell just prior to exec.
1384 * Note: as a result, we do not use signal handlers much. The only uses
1385 * are to count SIGCHLDs
1386 * and to restore tty pgrp on signal-induced exit.
1389 * Standard says "When a subshell is entered, traps that are not being ignored
1390 * are set to the default actions". bash interprets it so that traps which
1391 * are set to '' (ignore) are NOT reset to defaults. We do the same.
1393 * Problem: the above approach makes it unwieldy to catch signals while
1394 * we are in read builtin, or while we read commands from stdin:
1395 * masked signals are not visible!
1397 * New implementation
1398 * ==================
1399 * We record each signal we are interested in by installing signal handler
1400 * for them - a bit like emulating kernel pending signal mask in userspace.
1401 * We are interested in: signals which need to have special handling
1402 * as described above, and all signals which have traps set.
1403 * Signals are recorded in pending_set.
1404 * After each pipe execution, we extract any pending signals
1407 * unsigned special_sig_mask: a mask of shell-special signals.
1408 * unsigned fatal_sig_mask: a mask of signals on which we restore tty pgrp.
1409 * char *traps[sig] if trap for sig is set (even if it's '').
1410 * sigset_t pending_set: set of sigs we received.
1413 * if sig is in special_sig_mask, set handler back to:
1414 * record_pending_signo, or to IGN if it's a tty stop signal
1415 * if sig is in fatal_sig_mask, set handler back to sigexit.
1416 * else: set handler back to SIG_DFL
1417 * "trap 'cmd' SIGxxx":
1418 * set handler to record_pending_signo.
1420 * set handler to SIG_IGN.
1421 * after [v]fork, if we plan to be a shell:
1422 * set signals with special interactive handling to SIG_DFL
1423 * (because child shell is not interactive),
1424 * unset all traps except '' (note: regardless of child shell's type - {}, (), etc)
1425 * after [v]fork, if we plan to exec:
1426 * POSIX says fork clears pending signal mask in child - no need to clear it.
1428 * To make wait builtin interruptible, we handle SIGCHLD as special signal,
1429 * otherwise (if we leave it SIG_DFL) sigsuspend in wait builtin will not wake up on it.
1432 * Standard says "When a subshell is entered, traps that are not being ignored
1433 * are set to the default actions". bash interprets it so that traps which
1434 * are set to '' (ignore) are NOT reset to defaults. We do the same.
1437 SPECIAL_INTERACTIVE_SIGS = 0
1442 SPECIAL_JOBSTOP_SIGS = 0
1451 static void record_pending_signo(int sig)
1453 sigaddset(&G.pending_set, sig);
1454 #if ENABLE_HUSH_FAST
1455 if (sig == SIGCHLD) {
1457 //bb_error_msg("[%d] SIGCHLD_handler: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
1462 static sighandler_t install_sighandler(int sig, sighandler_t handler)
1464 struct sigaction old_sa;
1466 /* We could use signal() to install handlers... almost:
1467 * except that we need to mask ALL signals while handlers run.
1468 * I saw signal nesting in strace, race window isn't small.
1469 * SA_RESTART is also needed, but in Linux, signal()
1470 * sets SA_RESTART too.
1472 /* memset(&G.sa, 0, sizeof(G.sa)); - already done */
1473 /* sigfillset(&G.sa.sa_mask); - already done */
1474 /* G.sa.sa_flags = SA_RESTART; - already done */
1475 G.sa.sa_handler = handler;
1476 sigaction(sig, &G.sa, &old_sa);
1477 return old_sa.sa_handler;
1482 /* After [v]fork, in child: do not restore tty pgrp on xfunc death */
1483 # define disable_restore_tty_pgrp_on_exit() (die_sleep = 0)
1484 /* After [v]fork, in parent: restore tty pgrp on xfunc death */
1485 # define enable_restore_tty_pgrp_on_exit() (die_sleep = -1)
1487 /* Restores tty foreground process group, and exits.
1488 * May be called as signal handler for fatal signal
1489 * (will resend signal to itself, producing correct exit state)
1490 * or called directly with -EXITCODE.
1491 * We also call it if xfunc is exiting. */
1492 static void sigexit(int sig) NORETURN;
1493 static void sigexit(int sig)
1495 /* Careful: we can end up here after [v]fork. Do not restore
1496 * tty pgrp then, only top-level shell process does that */
1497 if (G_saved_tty_pgrp && getpid() == G.root_pid) {
1498 /* Disable all signals: job control, SIGPIPE, etc.
1499 * Mostly paranoid measure, to prevent infinite SIGTTOU.
1501 sigprocmask_allsigs(SIG_BLOCK);
1502 tcsetpgrp(G_interactive_fd, G_saved_tty_pgrp);
1505 /* Not a signal, just exit */
1509 kill_myself_with_sig(sig); /* does not return */
1513 # define disable_restore_tty_pgrp_on_exit() ((void)0)
1514 # define enable_restore_tty_pgrp_on_exit() ((void)0)
1518 static sighandler_t pick_sighandler(unsigned sig)
1520 sighandler_t handler = SIG_DFL;
1521 if (sig < sizeof(unsigned)*8) {
1522 unsigned sigmask = (1 << sig);
1526 if (G_fatal_sig_mask & sigmask)
1530 /* sig has special handling? */
1531 if (G.special_sig_mask & sigmask) {
1532 handler = record_pending_signo;
1533 /* TTIN/TTOU/TSTP can't be set to record_pending_signo
1534 * in order to ignore them: they will be raised
1535 * in an endless loop when we try to do some
1536 * terminal ioctls! We do have to _ignore_ these.
1538 if (SPECIAL_JOBSTOP_SIGS & sigmask)
1545 /* Restores tty foreground process group, and exits. */
1546 static void hush_exit(int exitcode) NORETURN;
1547 static void hush_exit(int exitcode)
1549 #if ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
1550 save_history(G.line_input_state);
1554 if (G.exiting <= 0 && G.traps && G.traps[0] && G.traps[0][0]) {
1556 /* argv[0] is unused */
1557 argv[1] = G.traps[0];
1559 G.exiting = 1; /* prevent EXIT trap recursion */
1560 /* Note: G.traps[0] is not cleared!
1561 * "trap" will still show it, if executed
1566 #if ENABLE_FEATURE_CLEAN_UP
1568 struct variable *cur_var;
1569 if (G.cwd != bb_msg_unknown)
1571 cur_var = G.top_var;
1573 struct variable *tmp = cur_var;
1574 if (!cur_var->max_len)
1575 free(cur_var->varstr);
1576 cur_var = cur_var->next;
1584 sigexit(- (exitcode & 0xff));
1591 //TODO: return a mask of ALL handled sigs?
1592 static int check_and_run_traps(void)
1599 if (sigisemptyset(&G.pending_set))
1604 if (sigismember(&G.pending_set, sig)) {
1605 sigdelset(&G.pending_set, sig);
1608 } while (sig < NSIG);
1611 if (G.traps && G.traps[sig]) {
1612 if (G.traps[sig][0]) {
1613 /* We have user-defined handler */
1614 smalluint save_rcode;
1616 /* argv[0] is unused */
1617 argv[1] = G.traps[sig];
1619 save_rcode = G.last_exitcode;
1621 G.last_exitcode = save_rcode;
1623 } /* else: "" trap, ignoring signal */
1626 /* not a trap: special action */
1629 /* Builtin was ^C'ed, make it look prettier: */
1637 /* bash is observed to signal whole process groups,
1638 * not individual processes */
1639 for (job = G.job_list; job; job = job->next) {
1642 debug_printf_exec("HUPing pgrp %d\n", job->pgrp);
1643 if (kill(- job->pgrp, SIGHUP) == 0)
1644 kill(- job->pgrp, SIGCONT);
1649 #if ENABLE_HUSH_FAST
1652 //bb_error_msg("[%d] check_and_run_traps: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
1654 * We dont do 'last_sig = sig' here -> NOT returning this sig.
1655 * This simplifies wait builtin a bit.
1659 default: /* ignored: */
1660 /* SIGTERM, SIGQUIT, SIGTTIN, SIGTTOU, SIGTSTP */
1662 * We dont do 'last_sig = sig' here -> NOT returning this sig.
1663 * Example: wait is not interrupted by TERM
1664 * in interactive shell, because TERM is ignored.
1673 static const char *get_cwd(int force)
1675 if (force || G.cwd == NULL) {
1676 /* xrealloc_getcwd_or_warn(arg) calls free(arg),
1677 * we must not try to free(bb_msg_unknown) */
1678 if (G.cwd == bb_msg_unknown)
1680 G.cwd = xrealloc_getcwd_or_warn((char *)G.cwd);
1682 G.cwd = bb_msg_unknown;
1689 * Shell and environment variable support
1691 static struct variable **get_ptr_to_local_var(const char *name, unsigned len)
1693 struct variable **pp;
1694 struct variable *cur;
1697 while ((cur = *pp) != NULL) {
1698 if (strncmp(cur->varstr, name, len) == 0 && cur->varstr[len] == '=')
1705 static const char* FAST_FUNC get_local_var_value(const char *name)
1707 struct variable **vpp;
1708 unsigned len = strlen(name);
1710 if (G.expanded_assignments) {
1711 char **cpp = G.expanded_assignments;
1714 if (strncmp(cp, name, len) == 0 && cp[len] == '=')
1715 return cp + len + 1;
1720 vpp = get_ptr_to_local_var(name, len);
1722 return (*vpp)->varstr + len + 1;
1724 if (strcmp(name, "PPID") == 0)
1725 return utoa(G.root_ppid);
1726 // bash compat: UID? EUID?
1727 #if ENABLE_HUSH_RANDOM_SUPPORT
1728 if (strcmp(name, "RANDOM") == 0)
1729 return utoa(next_random(&G.random_gen));
1734 /* str holds "NAME=VAL" and is expected to be malloced.
1735 * We take ownership of it.
1737 * 0: do not change export flag
1738 * (if creating new variable, flag will be 0)
1739 * 1: set export flag and putenv the variable
1740 * -1: clear export flag and unsetenv the variable
1741 * flg_read_only is set only when we handle -R var=val
1743 #if !BB_MMU && ENABLE_HUSH_LOCAL
1744 /* all params are used */
1745 #elif BB_MMU && ENABLE_HUSH_LOCAL
1746 #define set_local_var(str, flg_export, local_lvl, flg_read_only) \
1747 set_local_var(str, flg_export, local_lvl)
1748 #elif BB_MMU && !ENABLE_HUSH_LOCAL
1749 #define set_local_var(str, flg_export, local_lvl, flg_read_only) \
1750 set_local_var(str, flg_export)
1751 #elif !BB_MMU && !ENABLE_HUSH_LOCAL
1752 #define set_local_var(str, flg_export, local_lvl, flg_read_only) \
1753 set_local_var(str, flg_export, flg_read_only)
1755 static int set_local_var(char *str, int flg_export, int local_lvl, int flg_read_only)
1757 struct variable **var_pp;
1758 struct variable *cur;
1762 eq_sign = strchr(str, '=');
1763 if (!eq_sign) { /* not expected to ever happen? */
1768 name_len = eq_sign - str + 1; /* including '=' */
1769 var_pp = &G.top_var;
1770 while ((cur = *var_pp) != NULL) {
1771 if (strncmp(cur->varstr, str, name_len) != 0) {
1772 var_pp = &cur->next;
1775 /* We found an existing var with this name */
1776 if (cur->flg_read_only) {
1780 bb_error_msg("%s: readonly variable", str);
1784 if (flg_export == -1) { // "&& cur->flg_export" ?
1785 debug_printf_env("%s: unsetenv '%s'\n", __func__, str);
1790 #if ENABLE_HUSH_LOCAL
1791 if (cur->func_nest_level < local_lvl) {
1792 /* New variable is declared as local,
1793 * and existing one is global, or local
1794 * from enclosing function.
1795 * Remove and save old one: */
1796 *var_pp = cur->next;
1797 cur->next = *G.shadowed_vars_pp;
1798 *G.shadowed_vars_pp = cur;
1799 /* bash 3.2.33(1) and exported vars:
1801 * # f() { local z=a; env | grep ^z; }
1807 if (cur->flg_export)
1812 if (strcmp(cur->varstr + name_len, eq_sign + 1) == 0) {
1817 if (cur->max_len != 0) {
1818 if (cur->max_len >= strlen(str)) {
1819 /* This one is from startup env, reuse space */
1820 strcpy(cur->varstr, str);
1824 /* max_len == 0 signifies "malloced" var, which we can
1825 * (and has to) free */
1829 goto set_str_and_exp;
1832 /* Not found - create new variable struct */
1833 cur = xzalloc(sizeof(*cur));
1834 #if ENABLE_HUSH_LOCAL
1835 cur->func_nest_level = local_lvl;
1837 cur->next = *var_pp;
1843 cur->flg_read_only = flg_read_only;
1846 if (flg_export == 1)
1847 cur->flg_export = 1;
1848 if (name_len == 4 && cur->varstr[0] == 'P' && cur->varstr[1] == 'S')
1849 cmdedit_update_prompt();
1850 if (cur->flg_export) {
1851 if (flg_export == -1) {
1852 cur->flg_export = 0;
1853 /* unsetenv was already done */
1855 debug_printf_env("%s: putenv '%s'\n", __func__, cur->varstr);
1856 return putenv(cur->varstr);
1862 /* Used at startup and after each cd */
1863 static void set_pwd_var(int exp)
1865 set_local_var(xasprintf("PWD=%s", get_cwd(/*force:*/ 1)),
1866 /*exp:*/ exp, /*lvl:*/ 0, /*ro:*/ 0);
1869 static int unset_local_var_len(const char *name, int name_len)
1871 struct variable *cur;
1872 struct variable **var_pp;
1875 return EXIT_SUCCESS;
1876 var_pp = &G.top_var;
1877 while ((cur = *var_pp) != NULL) {
1878 if (strncmp(cur->varstr, name, name_len) == 0 && cur->varstr[name_len] == '=') {
1879 if (cur->flg_read_only) {
1880 bb_error_msg("%s: readonly variable", name);
1881 return EXIT_FAILURE;
1883 *var_pp = cur->next;
1884 debug_printf_env("%s: unsetenv '%s'\n", __func__, cur->varstr);
1885 bb_unsetenv(cur->varstr);
1886 if (name_len == 3 && cur->varstr[0] == 'P' && cur->varstr[1] == 'S')
1887 cmdedit_update_prompt();
1891 return EXIT_SUCCESS;
1893 var_pp = &cur->next;
1895 return EXIT_SUCCESS;
1898 static int unset_local_var(const char *name)
1900 return unset_local_var_len(name, strlen(name));
1903 static void unset_vars(char **strings)
1911 const char *eq = strchrnul(*v, '=');
1912 unset_local_var_len(*v, (int)(eq - *v));
1918 static void FAST_FUNC set_local_var_from_halves(const char *name, const char *val)
1920 char *var = xasprintf("%s=%s", name, val);
1921 set_local_var(var, /*flags:*/ 0, /*lvl:*/ 0, /*ro:*/ 0);
1926 * Helpers for "var1=val1 var2=val2 cmd" feature
1928 static void add_vars(struct variable *var)
1930 struct variable *next;
1934 var->next = G.top_var;
1936 if (var->flg_export) {
1937 debug_printf_env("%s: restoring exported '%s'\n", __func__, var->varstr);
1938 putenv(var->varstr);
1940 debug_printf_env("%s: restoring variable '%s'\n", __func__, var->varstr);
1946 static struct variable *set_vars_and_save_old(char **strings)
1949 struct variable *old = NULL;
1955 struct variable *var_p;
1956 struct variable **var_pp;
1959 eq = strchr(*s, '=');
1961 var_pp = get_ptr_to_local_var(*s, eq - *s);
1963 /* Remove variable from global linked list */
1965 debug_printf_env("%s: removing '%s'\n", __func__, var_p->varstr);
1966 *var_pp = var_p->next;
1967 /* Add it to returned list */
1971 set_local_var(*s, /*exp:*/ 1, /*lvl:*/ 0, /*ro:*/ 0);
1982 static void reinit_unicode_for_hush(void)
1984 /* Unicode support should be activated even if LANG is set
1985 * _during_ shell execution, not only if it was set when
1986 * shell was started. Therefore, re-check LANG every time:
1988 const char *s = get_local_var_value("LC_ALL");
1989 if (!s) s = get_local_var_value("LC_CTYPE");
1990 if (!s) s = get_local_var_value("LANG");
1998 static int FAST_FUNC static_get(struct in_str *i)
2009 static int FAST_FUNC static_peek(struct in_str *i)
2014 #if ENABLE_HUSH_INTERACTIVE
2016 static void cmdedit_update_prompt(void)
2018 if (ENABLE_FEATURE_EDITING_FANCY_PROMPT) {
2019 G.PS1 = get_local_var_value("PS1");
2022 G.PS2 = get_local_var_value("PS2");
2030 static const char *setup_prompt_string(int promptmode)
2032 const char *prompt_str;
2033 debug_printf("setup_prompt_string %d ", promptmode);
2034 if (!ENABLE_FEATURE_EDITING_FANCY_PROMPT) {
2035 /* Set up the prompt */
2036 if (promptmode == 0) { /* PS1 */
2038 /* bash uses $PWD value, even if it is set by user.
2039 * It uses current dir only if PWD is unset.
2040 * We always use current dir. */
2041 G.PS1 = xasprintf("%s %c ", get_cwd(0), (geteuid() != 0) ? '$' : '#');
2046 prompt_str = (promptmode == 0) ? G.PS1 : G.PS2;
2047 debug_printf("result '%s'\n", prompt_str);
2051 static void get_user_input(struct in_str *i)
2054 const char *prompt_str;
2056 prompt_str = setup_prompt_string(i->promptmode);
2057 # if ENABLE_FEATURE_EDITING
2058 /* Enable command line editing only while a command line
2059 * is actually being read */
2061 reinit_unicode_for_hush();
2063 /* buglet: SIGINT will not make new prompt to appear _at once_,
2064 * only after <Enter>. (^C will work) */
2065 r = read_line_input(G.line_input_state, prompt_str, G.user_input_buf, CONFIG_FEATURE_EDITING_MAX_LEN-1, /*timeout*/ -1);
2066 /* catch *SIGINT* etc (^C is handled by read_line_input) */
2067 check_and_run_traps();
2068 } while (r == 0 || G.flag_SIGINT); /* repeat if ^C or SIGINT */
2069 i->eof_flag = (r < 0);
2070 if (i->eof_flag) { /* EOF/error detected */
2071 G.user_input_buf[0] = EOF; /* yes, it will be truncated, it's ok */
2072 G.user_input_buf[1] = '\0';
2077 if (i->last_char == '\0' || i->last_char == '\n') {
2078 /* Why check_and_run_traps here? Try this interactively:
2079 * $ trap 'echo INT' INT; (sleep 2; kill -INT $$) &
2080 * $ <[enter], repeatedly...>
2081 * Without check_and_run_traps, handler never runs.
2083 check_and_run_traps();
2084 fputs(prompt_str, stdout);
2087 G.user_input_buf[0] = r = fgetc(i->file);
2088 /*G.user_input_buf[1] = '\0'; - already is and never changed */
2089 } while (G.flag_SIGINT);
2090 i->eof_flag = (r == EOF);
2092 i->p = G.user_input_buf;
2095 #endif /* INTERACTIVE */
2097 /* This is the magic location that prints prompts
2098 * and gets data back from the user */
2099 static int FAST_FUNC file_get(struct in_str *i)
2103 /* If there is data waiting, eat it up */
2104 if (i->p && *i->p) {
2105 #if ENABLE_HUSH_INTERACTIVE
2109 if (i->eof_flag && !*i->p)
2111 /* note: ch is never NUL */
2113 /* need to double check i->file because we might be doing something
2114 * more complicated by now, like sourcing or substituting. */
2115 #if ENABLE_HUSH_INTERACTIVE
2116 if (G_interactive_fd && i->file == stdin) {
2119 } while (!*i->p); /* need non-empty line */
2120 i->promptmode = 1; /* PS2 */
2124 do ch = fgetc(i->file); while (ch == '\0');
2126 debug_printf("file_get: got '%c' %d\n", ch, ch);
2131 /* All callers guarantee this routine will never
2132 * be used right after a newline, so prompting is not needed.
2134 static int FAST_FUNC file_peek(struct in_str *i)
2137 if (i->p && *i->p) {
2138 if (i->eof_flag && !i->p[1])
2141 /* note: ch is never NUL */
2143 do ch = fgetc(i->file); while (ch == '\0');
2144 i->eof_flag = (ch == EOF);
2145 i->peek_buf[0] = ch;
2146 i->peek_buf[1] = '\0';
2148 debug_printf("file_peek: got '%c' %d\n", ch, ch);
2152 static void setup_file_in_str(struct in_str *i, FILE *f)
2154 memset(i, 0, sizeof(*i));
2155 i->peek = file_peek;
2157 /* i->promptmode = 0; - PS1 (memset did it) */
2162 static void setup_string_in_str(struct in_str *i, const char *s)
2164 memset(i, 0, sizeof(*i));
2165 i->peek = static_peek;
2166 i->get = static_get;
2167 /* i->promptmode = 0; - PS1 (memset did it) */
2169 /* i->eof_flag = 0; */
2176 #define B_CHUNK (32 * sizeof(char*))
2178 static void o_reset_to_empty_unquoted(o_string *o)
2181 o->has_quoted_part = 0;
2186 static void o_free(o_string *o)
2189 memset(o, 0, sizeof(*o));
2192 static ALWAYS_INLINE void o_free_unsafe(o_string *o)
2197 static void o_grow_by(o_string *o, int len)
2199 if (o->length + len > o->maxlen) {
2200 o->maxlen += (2*len > B_CHUNK ? 2*len : B_CHUNK);
2201 o->data = xrealloc(o->data, 1 + o->maxlen);
2205 static void o_addchr(o_string *o, int ch)
2207 debug_printf("o_addchr: '%c' o->length=%d o=%p\n", ch, o->length, o);
2209 o->data[o->length] = ch;
2211 o->data[o->length] = '\0';
2214 static void o_addblock(o_string *o, const char *str, int len)
2217 memcpy(&o->data[o->length], str, len);
2219 o->data[o->length] = '\0';
2222 static void o_addstr(o_string *o, const char *str)
2224 o_addblock(o, str, strlen(str));
2228 static void nommu_addchr(o_string *o, int ch)
2234 # define nommu_addchr(o, str) ((void)0)
2237 static void o_addstr_with_NUL(o_string *o, const char *str)
2239 o_addblock(o, str, strlen(str) + 1);
2243 * HUSH_BRACE_EXPANSION code needs corresponding quoting on variable expansion side.
2244 * Currently, "v='{q,w}'; echo $v" erroneously expands braces in $v.
2245 * Apparently, on unquoted $v bash still does globbing
2246 * ("v='*.txt'; echo $v" prints all .txt files),
2247 * but NOT brace expansion! Thus, there should be TWO independent
2248 * quoting mechanisms on $v expansion side: one protects
2249 * $v from brace expansion, and other additionally protects "$v" against globbing.
2250 * We have only second one.
2253 #if ENABLE_HUSH_BRACE_EXPANSION
2254 # define MAYBE_BRACES "{}"
2256 # define MAYBE_BRACES ""
2259 /* My analysis of quoting semantics tells me that state information
2260 * is associated with a destination, not a source.
2262 static void o_addqchr(o_string *o, int ch)
2265 char *found = strchr("*?[\\" MAYBE_BRACES, ch);
2270 o->data[o->length] = '\\';
2273 o->data[o->length] = ch;
2275 o->data[o->length] = '\0';
2278 static void o_addQchr(o_string *o, int ch)
2281 if ((o->o_expflags & EXP_FLAG_ESC_GLOB_CHARS)
2282 && strchr("*?[\\" MAYBE_BRACES, ch)
2285 o->data[o->length] = '\\';
2289 o->data[o->length] = ch;
2291 o->data[o->length] = '\0';
2294 static void o_addqblock(o_string *o, const char *str, int len)
2299 int ordinary_cnt = strcspn(str, "*?[\\" MAYBE_BRACES);
2300 if (ordinary_cnt > len) /* paranoia */
2302 o_addblock(o, str, ordinary_cnt);
2303 if (ordinary_cnt == len)
2304 return; /* NUL is already added by o_addblock */
2305 str += ordinary_cnt;
2306 len -= ordinary_cnt + 1; /* we are processing + 1 char below */
2310 if (ch) { /* it is necessarily one of "*?[\\" MAYBE_BRACES */
2312 o->data[o->length] = '\\';
2316 o->data[o->length] = ch;
2319 o->data[o->length] = '\0';
2322 static void o_addQblock(o_string *o, const char *str, int len)
2324 if (!(o->o_expflags & EXP_FLAG_ESC_GLOB_CHARS)) {
2325 o_addblock(o, str, len);
2328 o_addqblock(o, str, len);
2331 static void o_addQstr(o_string *o, const char *str)
2333 o_addQblock(o, str, strlen(str));
2336 /* A special kind of o_string for $VAR and `cmd` expansion.
2337 * It contains char* list[] at the beginning, which is grown in 16 element
2338 * increments. Actual string data starts at the next multiple of 16 * (char*).
2339 * list[i] contains an INDEX (int!) into this string data.
2340 * It means that if list[] needs to grow, data needs to be moved higher up
2341 * but list[i]'s need not be modified.
2342 * NB: remembering how many list[i]'s you have there is crucial.
2343 * o_finalize_list() operation post-processes this structure - calculates
2344 * and stores actual char* ptrs in list[]. Oh, it NULL terminates it as well.
2346 #if DEBUG_EXPAND || DEBUG_GLOB
2347 static void debug_print_list(const char *prefix, o_string *o, int n)
2349 char **list = (char**)o->data;
2350 int string_start = ((n + 0xf) & ~0xf) * sizeof(list[0]);
2354 fdprintf(2, "%s: list:%p n:%d string_start:%d length:%d maxlen:%d glob:%d quoted:%d escape:%d\n",
2355 prefix, list, n, string_start, o->length, o->maxlen,
2356 !!(o->o_expflags & EXP_FLAG_GLOB),
2358 !!(o->o_expflags & EXP_FLAG_ESC_GLOB_CHARS));
2361 fdprintf(2, " list[%d]=%d '%s' %p\n", i, (int)(uintptr_t)list[i],
2362 o->data + (int)(uintptr_t)list[i] + string_start,
2363 o->data + (int)(uintptr_t)list[i] + string_start);
2367 const char *p = o->data + (int)(uintptr_t)list[n - 1] + string_start;
2369 fdprintf(2, " total_sz:%ld\n", (long)((p + strlen(p) + 1) - o->data));
2373 # define debug_print_list(prefix, o, n) ((void)0)
2376 /* n = o_save_ptr_helper(str, n) "starts new string" by storing an index value
2377 * in list[n] so that it points past last stored byte so far.
2378 * It returns n+1. */
2379 static int o_save_ptr_helper(o_string *o, int n)
2381 char **list = (char**)o->data;
2385 if (!o->has_empty_slot) {
2386 string_start = ((n + 0xf) & ~0xf) * sizeof(list[0]);
2387 string_len = o->length - string_start;
2388 if (!(n & 0xf)) { /* 0, 0x10, 0x20...? */
2389 debug_printf_list("list[%d]=%d string_start=%d (growing)\n", n, string_len, string_start);
2390 /* list[n] points to string_start, make space for 16 more pointers */
2391 o->maxlen += 0x10 * sizeof(list[0]);
2392 o->data = xrealloc(o->data, o->maxlen + 1);
2393 list = (char**)o->data;
2394 memmove(list + n + 0x10, list + n, string_len);
2395 o->length += 0x10 * sizeof(list[0]);
2397 debug_printf_list("list[%d]=%d string_start=%d\n",
2398 n, string_len, string_start);
2401 /* We have empty slot at list[n], reuse without growth */
2402 string_start = ((n+1 + 0xf) & ~0xf) * sizeof(list[0]); /* NB: n+1! */
2403 string_len = o->length - string_start;
2404 debug_printf_list("list[%d]=%d string_start=%d (empty slot)\n",
2405 n, string_len, string_start);
2406 o->has_empty_slot = 0;
2408 o->has_quoted_part = 0;
2409 list[n] = (char*)(uintptr_t)string_len;
2413 /* "What was our last o_save_ptr'ed position (byte offset relative o->data)?" */
2414 static int o_get_last_ptr(o_string *o, int n)
2416 char **list = (char**)o->data;
2417 int string_start = ((n + 0xf) & ~0xf) * sizeof(list[0]);
2419 return ((int)(uintptr_t)list[n-1]) + string_start;
2422 #if ENABLE_HUSH_BRACE_EXPANSION
2423 /* There in a GNU extension, GLOB_BRACE, but it is not usable:
2424 * first, it processes even {a} (no commas), second,
2425 * I didn't manage to make it return strings when they don't match
2426 * existing files. Need to re-implement it.
2430 static int glob_needed(const char *s)
2439 if (*s == '*' || *s == '[' || *s == '?' || *s == '{')
2445 /* Return pointer to next closing brace or to comma */
2446 static const char *next_brace_sub(const char *cp)
2450 while (*cp != '\0') {
2457 if ((*cp == '}' && depth-- == 0) || (*cp == ',' && depth == 0))
2463 return *cp != '\0' ? cp : NULL;
2465 /* Recursive brace globber. Note: may garble pattern[]. */
2466 static int glob_brace(char *pattern, o_string *o, int n)
2468 char *new_pattern_buf;
2475 debug_printf_glob("glob_brace('%s')\n", pattern);
2481 if (*begin == '{') {
2482 /* Find the first sub-pattern and at the same time
2483 * find the rest after the closing brace */
2484 next = next_brace_sub(begin);
2486 /* An illegal expression */
2490 /* "{abc}" with no commas - illegal
2491 * brace expr, disregard and skip it */
2497 if (*begin == '\\' && begin[1] != '\0')
2501 debug_printf_glob("begin:%s\n", begin);
2502 debug_printf_glob("next:%s\n", next);
2504 /* Now find the end of the whole brace expression */
2506 while (*rest != '}') {
2507 rest = next_brace_sub(rest);
2509 /* An illegal expression */
2512 debug_printf_glob("rest:%s\n", rest);
2514 rest_len = strlen(++rest) + 1;
2516 /* We are sure the brace expression is well-formed */
2518 /* Allocate working buffer large enough for our work */
2519 new_pattern_buf = xmalloc(strlen(pattern));
2521 /* We have a brace expression. BEGIN points to the opening {,
2522 * NEXT points past the terminator of the first element, and REST
2523 * points past the final }. We will accumulate result names from
2524 * recursive runs for each brace alternative in the buffer using
2529 /* Construct the new glob expression */
2532 mempcpy(new_pattern_buf,
2533 /* We know the prefix for all sub-patterns */
2534 pattern, begin - pattern),
2538 /* Note: glob_brace() may garble new_pattern_buf[].
2539 * That's why we re-copy prefix every time (1st memcpy above).
2541 n = glob_brace(new_pattern_buf, o, n);
2543 /* We saw the last entry */
2547 next = next_brace_sub(next);
2549 free(new_pattern_buf);
2557 memset(&globdata, 0, sizeof(globdata));
2558 gr = glob(pattern, 0, NULL, &globdata);
2559 debug_printf_glob("glob('%s'):%d\n", pattern, gr);
2561 if (gr == GLOB_NOMATCH) {
2562 globfree(&globdata);
2563 /* NB: garbles parameter */
2564 unbackslash(pattern);
2565 o_addstr_with_NUL(o, pattern);
2566 debug_printf_glob("glob pattern '%s' is literal\n", pattern);
2567 return o_save_ptr_helper(o, n);
2569 if (gr == GLOB_NOSPACE)
2570 bb_error_msg_and_die(bb_msg_memory_exhausted);
2571 /* GLOB_ABORTED? Only happens with GLOB_ERR flag,
2572 * but we didn't specify it. Paranoia again. */
2573 bb_error_msg_and_die("glob error %d on '%s'", gr, pattern);
2575 if (globdata.gl_pathv && globdata.gl_pathv[0]) {
2576 char **argv = globdata.gl_pathv;
2578 o_addstr_with_NUL(o, *argv);
2579 n = o_save_ptr_helper(o, n);
2585 globfree(&globdata);
2589 /* Performs globbing on last list[],
2590 * saving each result as a new list[].
2592 static int perform_glob(o_string *o, int n)
2594 char *pattern, *copy;
2596 debug_printf_glob("start perform_glob: n:%d o->data:%p\n", n, o->data);
2598 return o_save_ptr_helper(o, n);
2599 pattern = o->data + o_get_last_ptr(o, n);
2600 debug_printf_glob("glob pattern '%s'\n", pattern);
2601 if (!glob_needed(pattern)) {
2602 /* unbackslash last string in o in place, fix length */
2603 o->length = unbackslash(pattern) - o->data;
2604 debug_printf_glob("glob pattern '%s' is literal\n", pattern);
2605 return o_save_ptr_helper(o, n);
2608 copy = xstrdup(pattern);
2609 /* "forget" pattern in o */
2610 o->length = pattern - o->data;
2611 n = glob_brace(copy, o, n);
2614 debug_print_list("perform_glob returning", o, n);
2618 #else /* !HUSH_BRACE_EXPANSION */
2621 static int glob_needed(const char *s)
2630 if (*s == '*' || *s == '[' || *s == '?')
2636 /* Performs globbing on last list[],
2637 * saving each result as a new list[].
2639 static int perform_glob(o_string *o, int n)
2645 debug_printf_glob("start perform_glob: n:%d o->data:%p\n", n, o->data);
2647 return o_save_ptr_helper(o, n);
2648 pattern = o->data + o_get_last_ptr(o, n);
2649 debug_printf_glob("glob pattern '%s'\n", pattern);
2650 if (!glob_needed(pattern)) {
2652 /* unbackslash last string in o in place, fix length */
2653 o->length = unbackslash(pattern) - o->data;
2654 debug_printf_glob("glob pattern '%s' is literal\n", pattern);
2655 return o_save_ptr_helper(o, n);
2658 memset(&globdata, 0, sizeof(globdata));
2659 /* Can't use GLOB_NOCHECK: it does not unescape the string.
2660 * If we glob "*.\*" and don't find anything, we need
2661 * to fall back to using literal "*.*", but GLOB_NOCHECK
2662 * will return "*.\*"!
2664 gr = glob(pattern, 0, NULL, &globdata);
2665 debug_printf_glob("glob('%s'):%d\n", pattern, gr);
2667 if (gr == GLOB_NOMATCH) {
2668 globfree(&globdata);
2671 if (gr == GLOB_NOSPACE)
2672 bb_error_msg_and_die(bb_msg_memory_exhausted);
2673 /* GLOB_ABORTED? Only happens with GLOB_ERR flag,
2674 * but we didn't specify it. Paranoia again. */
2675 bb_error_msg_and_die("glob error %d on '%s'", gr, pattern);
2677 if (globdata.gl_pathv && globdata.gl_pathv[0]) {
2678 char **argv = globdata.gl_pathv;
2679 /* "forget" pattern in o */
2680 o->length = pattern - o->data;
2682 o_addstr_with_NUL(o, *argv);
2683 n = o_save_ptr_helper(o, n);
2689 globfree(&globdata);
2691 debug_print_list("perform_glob returning", o, n);
2695 #endif /* !HUSH_BRACE_EXPANSION */
2697 /* If o->o_expflags & EXP_FLAG_GLOB, glob the string so far remembered.
2698 * Otherwise, just finish current list[] and start new */
2699 static int o_save_ptr(o_string *o, int n)
2701 if (o->o_expflags & EXP_FLAG_GLOB) {
2702 /* If o->has_empty_slot, list[n] was already globbed
2703 * (if it was requested back then when it was filled)
2704 * so don't do that again! */
2705 if (!o->has_empty_slot)
2706 return perform_glob(o, n); /* o_save_ptr_helper is inside */
2708 return o_save_ptr_helper(o, n);
2711 /* "Please convert list[n] to real char* ptrs, and NULL terminate it." */
2712 static char **o_finalize_list(o_string *o, int n)
2717 n = o_save_ptr(o, n); /* force growth for list[n] if necessary */
2719 debug_print_list("finalized", o, n);
2720 debug_printf_expand("finalized n:%d\n", n);
2721 list = (char**)o->data;
2722 string_start = ((n + 0xf) & ~0xf) * sizeof(list[0]);
2726 list[n] = o->data + (int)(uintptr_t)list[n] + string_start;
2731 static void free_pipe_list(struct pipe *pi);
2733 /* Returns pi->next - next pipe in the list */
2734 static struct pipe *free_pipe(struct pipe *pi)
2739 debug_printf_clean("free_pipe (pid %d)\n", getpid());
2740 for (i = 0; i < pi->num_cmds; i++) {
2741 struct command *command;
2742 struct redir_struct *r, *rnext;
2744 command = &pi->cmds[i];
2745 debug_printf_clean(" command %d:\n", i);
2746 if (command->argv) {
2750 for (a = 0, p = command->argv; *p; a++, p++) {
2751 debug_printf_clean(" argv[%d] = %s\n", a, *p);
2754 free_strings(command->argv);
2755 //command->argv = NULL;
2757 /* not "else if": on syntax error, we may have both! */
2758 if (command->group) {
2759 debug_printf_clean(" begin group (cmd_type:%d)\n",
2761 free_pipe_list(command->group);
2762 debug_printf_clean(" end group\n");
2763 //command->group = NULL;
2765 /* else is crucial here.
2766 * If group != NULL, child_func is meaningless */
2767 #if ENABLE_HUSH_FUNCTIONS
2768 else if (command->child_func) {
2769 debug_printf_exec("cmd %p releases child func at %p\n", command, command->child_func);
2770 command->child_func->parent_cmd = NULL;
2774 free(command->group_as_string);
2775 //command->group_as_string = NULL;
2777 for (r = command->redirects; r; r = rnext) {
2778 debug_printf_clean(" redirect %d%s",
2779 r->rd_fd, redir_table[r->rd_type].descrip);
2780 /* guard against the case >$FOO, where foo is unset or blank */
2781 if (r->rd_filename) {
2782 debug_printf_clean(" fname:'%s'\n", r->rd_filename);
2783 free(r->rd_filename);
2784 //r->rd_filename = NULL;
2786 debug_printf_clean(" rd_dup:%d\n", r->rd_dup);
2790 //command->redirects = NULL;
2792 free(pi->cmds); /* children are an array, they get freed all at once */
2796 //pi->cmdtext = NULL;
2804 static void free_pipe_list(struct pipe *pi)
2808 debug_printf_clean("pipe reserved word %d\n", pi->res_word);
2810 debug_printf_clean("pipe followup code %d\n", pi->followup);
2816 /*** Parsing routines ***/
2818 #ifndef debug_print_tree
2819 static void debug_print_tree(struct pipe *pi, int lvl)
2821 static const char *const PIPE[] = {
2827 static const char *RES[] = {
2828 [RES_NONE ] = "NONE" ,
2831 [RES_THEN ] = "THEN" ,
2832 [RES_ELIF ] = "ELIF" ,
2833 [RES_ELSE ] = "ELSE" ,
2836 # if ENABLE_HUSH_LOOPS
2837 [RES_FOR ] = "FOR" ,
2838 [RES_WHILE] = "WHILE",
2839 [RES_UNTIL] = "UNTIL",
2841 [RES_DONE ] = "DONE" ,
2843 # if ENABLE_HUSH_LOOPS || ENABLE_HUSH_CASE
2846 # if ENABLE_HUSH_CASE
2847 [RES_CASE ] = "CASE" ,
2848 [RES_CASE_IN ] = "CASE_IN" ,
2849 [RES_MATCH] = "MATCH",
2850 [RES_CASE_BODY] = "CASE_BODY",
2851 [RES_ESAC ] = "ESAC" ,
2853 [RES_XXXX ] = "XXXX" ,
2854 [RES_SNTX ] = "SNTX" ,
2856 static const char *const CMDTYPE[] = {
2860 # if ENABLE_HUSH_FUNCTIONS
2869 fdprintf(2, "%*spipe %d res_word=%s followup=%d %s\n", lvl*2, "",
2870 pin, RES[pi->res_word], pi->followup, PIPE[pi->followup]);
2872 while (prn < pi->num_cmds) {
2873 struct command *command = &pi->cmds[prn];
2874 char **argv = command->argv;
2876 fdprintf(2, "%*s cmd %d assignment_cnt:%d",
2878 command->assignment_cnt);
2879 if (command->group) {
2880 fdprintf(2, " group %s: (argv=%p)%s%s\n",
2881 CMDTYPE[command->cmd_type],
2884 , " group_as_string:", command->group_as_string
2889 debug_print_tree(command->group, lvl+1);
2893 if (argv) while (*argv) {
2894 fdprintf(2, " '%s'", *argv);
2904 #endif /* debug_print_tree */
2906 static struct pipe *new_pipe(void)
2909 pi = xzalloc(sizeof(struct pipe));
2910 /*pi->followup = 0; - deliberately invalid value */
2911 /*pi->res_word = RES_NONE; - RES_NONE is 0 anyway */
2915 /* Command (member of a pipe) is complete, or we start a new pipe
2916 * if ctx->command is NULL.
2917 * No errors possible here.
2919 static int done_command(struct parse_context *ctx)
2921 /* The command is really already in the pipe structure, so
2922 * advance the pipe counter and make a new, null command. */
2923 struct pipe *pi = ctx->pipe;
2924 struct command *command = ctx->command;
2927 if (IS_NULL_CMD(command)) {
2928 debug_printf_parse("done_command: skipping null cmd, num_cmds=%d\n", pi->num_cmds);
2932 debug_printf_parse("done_command: ++num_cmds=%d\n", pi->num_cmds);
2933 //debug_print_tree(ctx->list_head, 20);
2935 debug_printf_parse("done_command: initializing, num_cmds=%d\n", pi->num_cmds);
2938 /* Only real trickiness here is that the uncommitted
2939 * command structure is not counted in pi->num_cmds. */
2940 pi->cmds = xrealloc(pi->cmds, sizeof(*pi->cmds) * (pi->num_cmds+1));
2941 ctx->command = command = &pi->cmds[pi->num_cmds];
2943 memset(command, 0, sizeof(*command));
2944 return pi->num_cmds; /* used only for 0/nonzero check */
2947 static void done_pipe(struct parse_context *ctx, pipe_style type)
2951 debug_printf_parse("done_pipe entered, followup %d\n", type);
2952 /* Close previous command */
2953 not_null = done_command(ctx);
2954 ctx->pipe->followup = type;
2956 ctx->pipe->pi_inverted = ctx->ctx_inverted;
2957 ctx->ctx_inverted = 0;
2958 ctx->pipe->res_word = ctx->ctx_res_w;
2961 /* Without this check, even just <enter> on command line generates
2962 * tree of three NOPs (!). Which is harmless but annoying.
2963 * IOW: it is safe to do it unconditionally. */
2966 || ctx->ctx_res_w == RES_FI
2968 #if ENABLE_HUSH_LOOPS
2969 || ctx->ctx_res_w == RES_DONE
2970 || ctx->ctx_res_w == RES_FOR
2971 || ctx->ctx_res_w == RES_IN
2973 #if ENABLE_HUSH_CASE
2974 || ctx->ctx_res_w == RES_ESAC
2978 debug_printf_parse("done_pipe: adding new pipe: "
2979 "not_null:%d ctx->ctx_res_w:%d\n",
2980 not_null, ctx->ctx_res_w);
2982 ctx->pipe->next = new_p;
2984 /* RES_THEN, RES_DO etc are "sticky" -
2985 * they remain set for pipes inside if/while.
2986 * This is used to control execution.
2987 * RES_FOR and RES_IN are NOT sticky (needed to support
2988 * cases where variable or value happens to match a keyword):
2990 #if ENABLE_HUSH_LOOPS
2991 if (ctx->ctx_res_w == RES_FOR
2992 || ctx->ctx_res_w == RES_IN)
2993 ctx->ctx_res_w = RES_NONE;
2995 #if ENABLE_HUSH_CASE
2996 if (ctx->ctx_res_w == RES_MATCH)
2997 ctx->ctx_res_w = RES_CASE_BODY;
2998 if (ctx->ctx_res_w == RES_CASE)
2999 ctx->ctx_res_w = RES_CASE_IN;
3001 ctx->command = NULL; /* trick done_command below */
3002 /* Create the memory for command, roughly:
3003 * ctx->pipe->cmds = new struct command;
3004 * ctx->command = &ctx->pipe->cmds[0];
3007 //debug_print_tree(ctx->list_head, 10);
3009 debug_printf_parse("done_pipe return\n");
3012 static void initialize_context(struct parse_context *ctx)
3014 memset(ctx, 0, sizeof(*ctx));
3015 ctx->pipe = ctx->list_head = new_pipe();
3016 /* Create the memory for command, roughly:
3017 * ctx->pipe->cmds = new struct command;
3018 * ctx->command = &ctx->pipe->cmds[0];
3023 /* If a reserved word is found and processed, parse context is modified
3024 * and 1 is returned.
3027 struct reserved_combo {
3030 unsigned char assignment_flag;
3034 FLAG_END = (1 << RES_NONE ),
3036 FLAG_IF = (1 << RES_IF ),
3037 FLAG_THEN = (1 << RES_THEN ),
3038 FLAG_ELIF = (1 << RES_ELIF ),
3039 FLAG_ELSE = (1 << RES_ELSE ),
3040 FLAG_FI = (1 << RES_FI ),
3042 # if ENABLE_HUSH_LOOPS
3043 FLAG_FOR = (1 << RES_FOR ),
3044 FLAG_WHILE = (1 << RES_WHILE),
3045 FLAG_UNTIL = (1 << RES_UNTIL),
3046 FLAG_DO = (1 << RES_DO ),
3047 FLAG_DONE = (1 << RES_DONE ),
3048 FLAG_IN = (1 << RES_IN ),
3050 # if ENABLE_HUSH_CASE
3051 FLAG_MATCH = (1 << RES_MATCH),
3052 FLAG_ESAC = (1 << RES_ESAC ),
3054 FLAG_START = (1 << RES_XXXX ),
3057 static const struct reserved_combo* match_reserved_word(o_string *word)
3059 /* Mostly a list of accepted follow-up reserved words.
3060 * FLAG_END means we are done with the sequence, and are ready
3061 * to turn the compound list into a command.
3062 * FLAG_START means the word must start a new compound list.
3064 static const struct reserved_combo reserved_list[] = {
3066 { "!", RES_NONE, NOT_ASSIGNMENT , 0 },
3067 { "if", RES_IF, MAYBE_ASSIGNMENT, FLAG_THEN | FLAG_START },
3068 { "then", RES_THEN, MAYBE_ASSIGNMENT, FLAG_ELIF | FLAG_ELSE | FLAG_FI },
3069 { "elif", RES_ELIF, MAYBE_ASSIGNMENT, FLAG_THEN },
3070 { "else", RES_ELSE, MAYBE_ASSIGNMENT, FLAG_FI },
3071 { "fi", RES_FI, NOT_ASSIGNMENT , FLAG_END },
3073 # if ENABLE_HUSH_LOOPS
3074 { "for", RES_FOR, NOT_ASSIGNMENT , FLAG_IN | FLAG_DO | FLAG_START },
3075 { "while", RES_WHILE, MAYBE_ASSIGNMENT, FLAG_DO | FLAG_START },
3076 { "until", RES_UNTIL, MAYBE_ASSIGNMENT, FLAG_DO | FLAG_START },
3077 { "in", RES_IN, NOT_ASSIGNMENT , FLAG_DO },
3078 { "do", RES_DO, MAYBE_ASSIGNMENT, FLAG_DONE },
3079 { "done", RES_DONE, NOT_ASSIGNMENT , FLAG_END },
3081 # if ENABLE_HUSH_CASE
3082 { "case", RES_CASE, NOT_ASSIGNMENT , FLAG_MATCH | FLAG_START },
3083 { "esac", RES_ESAC, NOT_ASSIGNMENT , FLAG_END },
3086 const struct reserved_combo *r;
3088 for (r = reserved_list; r < reserved_list + ARRAY_SIZE(reserved_list); r++) {
3089 if (strcmp(word->data, r->literal) == 0)
3094 /* Return 0: not a keyword, 1: keyword
3096 static int reserved_word(o_string *word, struct parse_context *ctx)
3098 # if ENABLE_HUSH_CASE
3099 static const struct reserved_combo reserved_match = {
3100 "", RES_MATCH, NOT_ASSIGNMENT , FLAG_MATCH | FLAG_ESAC
3103 const struct reserved_combo *r;
3105 if (word->has_quoted_part)
3107 r = match_reserved_word(word);
3111 debug_printf("found reserved word %s, res %d\n", r->literal, r->res);
3112 # if ENABLE_HUSH_CASE
3113 if (r->res == RES_IN && ctx->ctx_res_w == RES_CASE_IN) {
3114 /* "case word IN ..." - IN part starts first MATCH part */
3115 r = &reserved_match;
3118 if (r->flag == 0) { /* '!' */
3119 if (ctx->ctx_inverted) { /* bash doesn't accept '! ! true' */
3120 syntax_error("! ! command");
3121 ctx->ctx_res_w = RES_SNTX;
3123 ctx->ctx_inverted = 1;
3126 if (r->flag & FLAG_START) {
3127 struct parse_context *old;
3129 old = xmalloc(sizeof(*old));
3130 debug_printf_parse("push stack %p\n", old);
3131 *old = *ctx; /* physical copy */
3132 initialize_context(ctx);
3134 } else if (/*ctx->ctx_res_w == RES_NONE ||*/ !(ctx->old_flag & (1 << r->res))) {
3135 syntax_error_at(word->data);
3136 ctx->ctx_res_w = RES_SNTX;
3139 /* "{...} fi" is ok. "{...} if" is not
3141 * if { echo foo; } then { echo bar; } fi */
3142 if (ctx->command->group)
3143 done_pipe(ctx, PIPE_SEQ);
3146 ctx->ctx_res_w = r->res;
3147 ctx->old_flag = r->flag;
3148 word->o_assignment = r->assignment_flag;
3149 debug_printf_parse("word->o_assignment='%s'\n", assignment_flag[word->o_assignment]);
3151 if (ctx->old_flag & FLAG_END) {
3152 struct parse_context *old;
3154 done_pipe(ctx, PIPE_SEQ);
3155 debug_printf_parse("pop stack %p\n", ctx->stack);
3157 old->command->group = ctx->list_head;
3158 old->command->cmd_type = CMD_NORMAL;
3160 o_addstr(&old->as_string, ctx->as_string.data);
3161 o_free_unsafe(&ctx->as_string);
3162 old->command->group_as_string = xstrdup(old->as_string.data);
3163 debug_printf_parse("pop, remembering as:'%s'\n",
3164 old->command->group_as_string);
3166 *ctx = *old; /* physical copy */
3171 #endif /* HAS_KEYWORDS */
3173 /* Word is complete, look at it and update parsing context.
3174 * Normal return is 0. Syntax errors return 1.
3175 * Note: on return, word is reset, but not o_free'd!
3177 static int done_word(o_string *word, struct parse_context *ctx)
3179 struct command *command = ctx->command;
3181 debug_printf_parse("done_word entered: '%s' %p\n", word->data, command);
3182 if (word->length == 0 && !word->has_quoted_part) {
3183 debug_printf_parse("done_word return 0: true null, ignored\n");
3187 if (ctx->pending_redirect) {
3188 /* We do not glob in e.g. >*.tmp case. bash seems to glob here
3189 * only if run as "bash", not "sh" */
3190 /* http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html
3192 * ...the word that follows the redirection operator
3193 * shall be subjected to tilde expansion, parameter expansion,
3194 * command substitution, arithmetic expansion, and quote
3195 * removal. Pathname expansion shall not be performed
3196 * on the word by a non-interactive shell; an interactive
3197 * shell may perform it, but shall do so only when
3198 * the expansion would result in one word."
3200 ctx->pending_redirect->rd_filename = xstrdup(word->data);
3201 /* Cater for >\file case:
3202 * >\a creates file a; >\\a, >"\a", >"\\a" create file \a
3203 * Same with heredocs:
3204 * for <<\H delim is H; <<\\H, <<"\H", <<"\\H" - \H
3206 if (ctx->pending_redirect->rd_type == REDIRECT_HEREDOC) {
3207 unbackslash(ctx->pending_redirect->rd_filename);
3208 /* Is it <<"HEREDOC"? */
3209 if (word->has_quoted_part) {
3210 ctx->pending_redirect->rd_dup |= HEREDOC_QUOTED;
3213 debug_printf_parse("word stored in rd_filename: '%s'\n", word->data);
3214 ctx->pending_redirect = NULL;
3217 # if ENABLE_HUSH_CASE
3218 if (ctx->ctx_dsemicolon
3219 && strcmp(word->data, "esac") != 0 /* not "... pattern) cmd;; esac" */
3221 /* already done when ctx_dsemicolon was set to 1: */
3222 /* ctx->ctx_res_w = RES_MATCH; */
3223 ctx->ctx_dsemicolon = 0;
3226 if (!command->argv /* if it's the first word... */
3227 # if ENABLE_HUSH_LOOPS
3228 && ctx->ctx_res_w != RES_FOR /* ...not after FOR or IN */
3229 && ctx->ctx_res_w != RES_IN
3231 # if ENABLE_HUSH_CASE
3232 && ctx->ctx_res_w != RES_CASE
3235 int reserved = reserved_word(word, ctx);
3236 debug_printf_parse("checking for reserved-ness: %d\n", reserved);
3238 o_reset_to_empty_unquoted(word);
3239 debug_printf_parse("done_word return %d\n",
3240 (ctx->ctx_res_w == RES_SNTX));
3241 return (ctx->ctx_res_w == RES_SNTX);
3243 # if ENABLE_HUSH_BASH_COMPAT
3244 if (strcmp(word->data, "[[") == 0) {
3245 command->cmd_type = CMD_SINGLEWORD_NOGLOB;
3251 if (command->group) {
3252 /* "{ echo foo; } echo bar" - bad */
3253 syntax_error_at(word->data);
3254 debug_printf_parse("done_word return 1: syntax error, "
3255 "groups and arglists don't mix\n");
3259 /* If this word wasn't an assignment, next ones definitely
3260 * can't be assignments. Even if they look like ones. */
3261 if (word->o_assignment != DEFINITELY_ASSIGNMENT
3262 && word->o_assignment != WORD_IS_KEYWORD
3264 word->o_assignment = NOT_ASSIGNMENT;
3266 if (word->o_assignment == DEFINITELY_ASSIGNMENT) {
3267 command->assignment_cnt++;
3268 debug_printf_parse("++assignment_cnt=%d\n", command->assignment_cnt);
3270 debug_printf_parse("word->o_assignment was:'%s'\n", assignment_flag[word->o_assignment]);
3271 word->o_assignment = MAYBE_ASSIGNMENT;
3273 debug_printf_parse("word->o_assignment='%s'\n", assignment_flag[word->o_assignment]);
3275 if (word->has_quoted_part
3276 /* optimization: and if it's ("" or '') or ($v... or `cmd`...): */
3277 && (word->data[0] == '\0' || word->data[0] == SPECIAL_VAR_SYMBOL)
3278 /* (otherwise it's known to be not empty and is already safe) */
3280 /* exclude "$@" - it can expand to no word despite "" */
3281 char *p = word->data;
3282 while (p[0] == SPECIAL_VAR_SYMBOL
3283 && (p[1] & 0x7f) == '@'
3284 && p[2] == SPECIAL_VAR_SYMBOL
3289 command->argv = add_string_to_strings(command->argv, xstrdup(word->data));
3290 debug_print_strings("word appended to argv", command->argv);
3293 #if ENABLE_HUSH_LOOPS
3294 if (ctx->ctx_res_w == RES_FOR) {
3295 if (word->has_quoted_part
3296 || !is_well_formed_var_name(command->argv[0], '\0')
3298 /* bash says just "not a valid identifier" */
3299 syntax_error("not a valid identifier in for");
3302 /* Force FOR to have just one word (variable name) */
3303 /* NB: basically, this makes hush see "for v in ..."
3304 * syntax as if it is "for v; in ...". FOR and IN become
3305 * two pipe structs in parse tree. */
3306 done_pipe(ctx, PIPE_SEQ);
3309 #if ENABLE_HUSH_CASE
3310 /* Force CASE to have just one word */
3311 if (ctx->ctx_res_w == RES_CASE) {
3312 done_pipe(ctx, PIPE_SEQ);
3316 o_reset_to_empty_unquoted(word);
3318 debug_printf_parse("done_word return 0\n");
3323 /* Peek ahead in the input to find out if we have a "&n" construct,
3324 * as in "2>&1", that represents duplicating a file descriptor.
3326 * REDIRFD_CLOSE if >&- "close fd" construct is seen,
3327 * REDIRFD_SYNTAX_ERR if syntax error,
3328 * REDIRFD_TO_FILE if no & was seen,
3329 * or the number found.
3332 #define parse_redir_right_fd(as_string, input) \
3333 parse_redir_right_fd(input)
3335 static int parse_redir_right_fd(o_string *as_string, struct in_str *input)
3341 return REDIRFD_TO_FILE;
3343 ch = i_getch(input); /* get the & */
3344 nommu_addchr(as_string, ch);
3347 ch = i_getch(input);
3348 nommu_addchr(as_string, ch);
3349 return REDIRFD_CLOSE;
3353 while (ch != EOF && isdigit(ch)) {
3354 d = d*10 + (ch-'0');
3356 ch = i_getch(input);
3357 nommu_addchr(as_string, ch);
3362 //TODO: this is the place to catch ">&file" bashism (redirect both fd 1 and 2)
3364 bb_error_msg("ambiguous redirect");
3365 return REDIRFD_SYNTAX_ERR;
3368 /* Return code is 0 normal, 1 if a syntax error is detected
3370 static int parse_redirect(struct parse_context *ctx,
3373 struct in_str *input)
3375 struct command *command = ctx->command;
3376 struct redir_struct *redir;
3377 struct redir_struct **redirp;
3380 dup_num = REDIRFD_TO_FILE;
3381 if (style != REDIRECT_HEREDOC) {
3382 /* Check for a '>&1' type redirect */
3383 dup_num = parse_redir_right_fd(&ctx->as_string, input);
3384 if (dup_num == REDIRFD_SYNTAX_ERR)
3387 int ch = i_peek(input);
3388 dup_num = (ch == '-'); /* HEREDOC_SKIPTABS bit is 1 */
3389 if (dup_num) { /* <<-... */
3390 ch = i_getch(input);
3391 nommu_addchr(&ctx->as_string, ch);
3396 if (style == REDIRECT_OVERWRITE && dup_num == REDIRFD_TO_FILE) {
3397 int ch = i_peek(input);
3399 /* >|FILE redirect ("clobbering" >).
3400 * Since we do not support "set -o noclobber" yet,
3401 * >| and > are the same for now. Just eat |.
3403 ch = i_getch(input);
3404 nommu_addchr(&ctx->as_string, ch);
3408 /* Create a new redir_struct and append it to the linked list */
3409 redirp = &command->redirects;
3410 while ((redir = *redirp) != NULL) {
3411 redirp = &(redir->next);
3413 *redirp = redir = xzalloc(sizeof(*redir));
3414 /* redir->next = NULL; */
3415 /* redir->rd_filename = NULL; */
3416 redir->rd_type = style;
3417 redir->rd_fd = (fd == -1) ? redir_table[style].default_fd : fd;
3419 debug_printf_parse("redirect type %d %s\n", redir->rd_fd,
3420 redir_table[style].descrip);
3422 redir->rd_dup = dup_num;
3423 if (style != REDIRECT_HEREDOC && dup_num != REDIRFD_TO_FILE) {
3424 /* Erik had a check here that the file descriptor in question
3425 * is legit; I postpone that to "run time"
3426 * A "-" representation of "close me" shows up as a -3 here */
3427 debug_printf_parse("duplicating redirect '%d>&%d'\n",
3428 redir->rd_fd, redir->rd_dup);
3430 /* Set ctx->pending_redirect, so we know what to do at the
3431 * end of the next parsed word. */
3432 ctx->pending_redirect = redir;
3437 /* If a redirect is immediately preceded by a number, that number is
3438 * supposed to tell which file descriptor to redirect. This routine
3439 * looks for such preceding numbers. In an ideal world this routine
3440 * needs to handle all the following classes of redirects...
3441 * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
3442 * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
3443 * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
3444 * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
3446 * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html
3448 * ... If n is quoted, the number shall not be recognized as part of
3449 * the redirection expression. For example:
3451 * writes the character 2 into file a"
3452 * We are getting it right by setting ->has_quoted_part on any \<char>
3454 * A -1 return means no valid number was found,
3455 * the caller should use the appropriate default for this redirection.
3457 static int redirect_opt_num(o_string *o)
3461 if (o->data == NULL)
3463 num = bb_strtou(o->data, NULL, 10);
3464 if (errno || num < 0)
3466 o_reset_to_empty_unquoted(o);
3471 #define fetch_till_str(as_string, input, word, skip_tabs) \
3472 fetch_till_str(input, word, skip_tabs)
3474 static char *fetch_till_str(o_string *as_string,
3475 struct in_str *input,
3479 o_string heredoc = NULL_O_STRING;
3481 int prev = 0; /* not \ */
3487 ch = i_getch(input);
3489 nommu_addchr(as_string, ch);
3490 if ((ch == '\n' || ch == EOF)
3491 && ((heredoc_flags & HEREDOC_QUOTED) || prev != '\\')
3493 if (strcmp(heredoc.data + past_EOL, word) == 0) {
3494 heredoc.data[past_EOL] = '\0';
3495 debug_printf_parse("parsed heredoc '%s'\n", heredoc.data);
3496 return heredoc.data;
3498 while (ch == '\n') {
3499 o_addchr(&heredoc, ch);
3502 past_EOL = heredoc.length;
3504 ch = i_getch(input);
3506 nommu_addchr(as_string, ch);
3507 } while ((heredoc_flags & HEREDOC_SKIPTABS) && ch == '\t');
3511 o_free_unsafe(&heredoc);
3514 o_addchr(&heredoc, ch);
3515 nommu_addchr(as_string, ch);
3516 if (prev == '\\' && ch == '\\')
3517 /* Correctly handle foo\\<eol> (not a line cont.) */
3518 prev = 0; /* not \ */
3524 /* Look at entire parse tree for not-yet-loaded REDIRECT_HEREDOCs
3525 * and load them all. There should be exactly heredoc_cnt of them.
3527 static int fetch_heredocs(int heredoc_cnt, struct parse_context *ctx, struct in_str *input)
3529 struct pipe *pi = ctx->list_head;
3531 while (pi && heredoc_cnt) {
3533 struct command *cmd = pi->cmds;
3535 debug_printf_parse("fetch_heredocs: num_cmds:%d cmd argv0:'%s'\n",
3537 cmd->argv ? cmd->argv[0] : "NONE");
3538 for (i = 0; i < pi->num_cmds; i++) {
3539 struct redir_struct *redir = cmd->redirects;
3541 debug_printf_parse("fetch_heredocs: %d cmd argv0:'%s'\n",
3542 i, cmd->argv ? cmd->argv[0] : "NONE");
3544 if (redir->rd_type == REDIRECT_HEREDOC) {
3547 redir->rd_type = REDIRECT_HEREDOC2;
3548 /* redir->rd_dup is (ab)used to indicate <<- */
3549 p = fetch_till_str(&ctx->as_string, input,
3550 redir->rd_filename, redir->rd_dup);
3552 syntax_error("unexpected EOF in here document");
3555 free(redir->rd_filename);
3556 redir->rd_filename = p;
3559 redir = redir->next;
3566 /* Should be 0. If it isn't, it's a parse error */
3568 bb_error_msg_and_die("heredoc BUG 2");
3574 static int run_list(struct pipe *pi);
3576 #define parse_stream(pstring, input, end_trigger) \
3577 parse_stream(input, end_trigger)
3579 static struct pipe *parse_stream(char **pstring,
3580 struct in_str *input,
3584 #if !ENABLE_HUSH_FUNCTIONS
3585 #define parse_group(dest, ctx, input, ch) \
3586 parse_group(ctx, input, ch)
3588 static int parse_group(o_string *dest, struct parse_context *ctx,
3589 struct in_str *input, int ch)
3591 /* dest contains characters seen prior to ( or {.
3592 * Typically it's empty, but for function defs,
3593 * it contains function name (without '()'). */
3594 struct pipe *pipe_list;
3596 struct command *command = ctx->command;
3598 debug_printf_parse("parse_group entered\n");
3599 #if ENABLE_HUSH_FUNCTIONS
3600 if (ch == '(' && !dest->has_quoted_part) {
3602 if (done_word(dest, ctx))
3605 goto skip; /* (... */
3606 if (command->argv[1]) { /* word word ... (... */
3607 syntax_error_unexpected_ch('(');
3610 /* it is "word(..." or "word (..." */
3612 ch = i_getch(input);
3613 while (ch == ' ' || ch == '\t');
3615 syntax_error_unexpected_ch(ch);
3618 nommu_addchr(&ctx->as_string, ch);
3620 ch = i_getch(input);
3621 while (ch == ' ' || ch == '\t' || ch == '\n');
3623 syntax_error_unexpected_ch(ch);
3626 nommu_addchr(&ctx->as_string, ch);
3627 command->cmd_type = CMD_FUNCDEF;
3632 #if 0 /* Prevented by caller */
3633 if (command->argv /* word [word]{... */
3634 || dest->length /* word{... */
3635 || dest->has_quoted_part /* ""{... */
3638 debug_printf_parse("parse_group return 1: "
3639 "syntax error, groups and arglists don't mix\n");
3644 #if ENABLE_HUSH_FUNCTIONS
3650 command->cmd_type = CMD_SUBSHELL;
3652 /* bash does not allow "{echo...", requires whitespace */
3653 ch = i_getch(input);
3654 if (ch != ' ' && ch != '\t' && ch != '\n') {
3655 syntax_error_unexpected_ch(ch);
3658 nommu_addchr(&ctx->as_string, ch);
3663 # define as_string NULL
3665 char *as_string = NULL;
3667 pipe_list = parse_stream(&as_string, input, endch);
3670 o_addstr(&ctx->as_string, as_string);
3672 /* empty ()/{} or parse error? */
3673 if (!pipe_list || pipe_list == ERR_PTR) {
3674 /* parse_stream already emitted error msg */
3677 debug_printf_parse("parse_group return 1: "
3678 "parse_stream returned %p\n", pipe_list);
3681 command->group = pipe_list;
3683 as_string[strlen(as_string) - 1] = '\0'; /* plink ')' or '}' */
3684 command->group_as_string = as_string;
3685 debug_printf_parse("end of group, remembering as:'%s'\n",
3686 command->group_as_string);
3690 debug_printf_parse("parse_group return 0\n");
3692 /* command remains "open", available for possible redirects */
3695 #if ENABLE_HUSH_TICK || ENABLE_SH_MATH_SUPPORT || ENABLE_HUSH_DOLLAR_OPS
3696 /* Subroutines for copying $(...) and `...` things */
3697 static int add_till_backquote(o_string *dest, struct in_str *input, int in_dquote);
3699 static int add_till_single_quote(o_string *dest, struct in_str *input)
3702 int ch = i_getch(input);
3704 syntax_error_unterm_ch('\'');
3712 /* "...\"...`..`...." - do we need to handle "...$(..)..." too? */
3713 static int add_till_double_quote(o_string *dest, struct in_str *input)
3716 int ch = i_getch(input);
3718 syntax_error_unterm_ch('"');
3723 if (ch == '\\') { /* \x. Copy both chars. */
3725 ch = i_getch(input);
3729 if (!add_till_backquote(dest, input, /*in_dquote:*/ 1))
3734 //if (ch == '$') ...
3737 /* Process `cmd` - copy contents until "`" is seen. Complicated by
3739 * "Within the backquoted style of command substitution, backslash
3740 * shall retain its literal meaning, except when followed by: '$', '`', or '\'.
3741 * The search for the matching backquote shall be satisfied by the first
3742 * backquote found without a preceding backslash; during this search,
3743 * if a non-escaped backquote is encountered within a shell comment,
3744 * a here-document, an embedded command substitution of the $(command)
3745 * form, or a quoted string, undefined results occur. A single-quoted
3746 * or double-quoted string that begins, but does not end, within the
3747 * "`...`" sequence produces undefined results."
3749 * echo `echo '\'TEST\`echo ZZ\`BEST` \TESTZZBEST
3751 static int add_till_backquote(o_string *dest, struct in_str *input, int in_dquote)
3754 int ch = i_getch(input);
3758 /* \x. Copy both unless it is \`, \$, \\ and maybe \" */
3759 ch = i_getch(input);
3763 && (!in_dquote || ch != '"')
3765 o_addchr(dest, '\\');
3769 syntax_error_unterm_ch('`');
3775 /* Process $(cmd) - copy contents until ")" is seen. Complicated by
3776 * quoting and nested ()s.
3777 * "With the $(command) style of command substitution, all characters
3778 * following the open parenthesis to the matching closing parenthesis
3779 * constitute the command. Any valid shell script can be used for command,
3780 * except a script consisting solely of redirections which produces
3781 * unspecified results."
3783 * echo $(echo '(TEST)' BEST) (TEST) BEST
3784 * echo $(echo 'TEST)' BEST) TEST) BEST
3785 * echo $(echo \(\(TEST\) BEST) ((TEST) BEST
3787 * Also adapted to eat ${var%...} and $((...)) constructs, since ... part
3788 * can contain arbitrary constructs, just like $(cmd).
3789 * In bash compat mode, it needs to also be able to stop on ':' or '/'
3790 * for ${var:N[:M]} and ${var/P[/R]} parsing.
3792 #define DOUBLE_CLOSE_CHAR_FLAG 0x80
3793 static int add_till_closing_bracket(o_string *dest, struct in_str *input, unsigned end_ch)
3796 char dbl = end_ch & DOUBLE_CLOSE_CHAR_FLAG;
3797 # if ENABLE_HUSH_BASH_COMPAT
3798 char end_char2 = end_ch >> 8;
3800 end_ch &= (DOUBLE_CLOSE_CHAR_FLAG - 1);
3803 ch = i_getch(input);
3805 syntax_error_unterm_ch(end_ch);
3808 if (ch == end_ch IF_HUSH_BASH_COMPAT( || ch == end_char2)) {
3811 /* we look for closing )) of $((EXPR)) */
3812 if (i_peek(input) == end_ch) {
3813 i_getch(input); /* eat second ')' */
3818 if (ch == '(' || ch == '{') {
3819 ch = (ch == '(' ? ')' : '}');
3820 if (!add_till_closing_bracket(dest, input, ch))
3826 if (!add_till_single_quote(dest, input))
3832 if (!add_till_double_quote(dest, input))
3838 if (!add_till_backquote(dest, input, /*in_dquote:*/ 0))
3844 /* \x. Copy verbatim. Important for \(, \) */
3845 ch = i_getch(input);
3847 syntax_error_unterm_ch(')');
3856 #endif /* ENABLE_HUSH_TICK || ENABLE_SH_MATH_SUPPORT || ENABLE_HUSH_DOLLAR_OPS */
3858 /* Return code: 0 for OK, 1 for syntax error */
3860 #define parse_dollar(as_string, dest, input, quote_mask) \
3861 parse_dollar(dest, input, quote_mask)
3862 #define as_string NULL
3864 static int parse_dollar(o_string *as_string,
3866 struct in_str *input, unsigned char quote_mask)
3868 int ch = i_peek(input); /* first character after the $ */
3870 debug_printf_parse("parse_dollar entered: ch='%c'\n", ch);
3872 ch = i_getch(input);
3873 nommu_addchr(as_string, ch);
3875 o_addchr(dest, SPECIAL_VAR_SYMBOL);
3877 debug_printf_parse(": '%c'\n", ch);
3878 o_addchr(dest, ch | quote_mask);
3881 if (!isalnum(ch) && ch != '_')
3883 ch = i_getch(input);
3884 nommu_addchr(as_string, ch);
3886 o_addchr(dest, SPECIAL_VAR_SYMBOL);
3887 } else if (isdigit(ch)) {
3889 ch = i_getch(input);
3890 nommu_addchr(as_string, ch);
3891 o_addchr(dest, SPECIAL_VAR_SYMBOL);
3892 debug_printf_parse(": '%c'\n", ch);
3893 o_addchr(dest, ch | quote_mask);
3894 o_addchr(dest, SPECIAL_VAR_SYMBOL);
3895 } else switch (ch) {
3897 case '!': /* last bg pid */
3898 case '?': /* last exit code */
3899 case '#': /* number of args */
3900 case '*': /* args */
3901 case '@': /* args */
3902 goto make_one_char_var;
3904 o_addchr(dest, SPECIAL_VAR_SYMBOL);
3906 ch = i_getch(input); /* eat '{' */
3907 nommu_addchr(as_string, ch);
3909 ch = i_getch(input); /* first char after '{' */
3910 /* It should be ${?}, or ${#var},
3911 * or even ${?+subst} - operator acting on a special variable,
3912 * or the beginning of variable name.
3915 || (!strchr(_SPECIAL_VARS_STR, ch) && !isalnum(ch)) /* not one of those */
3918 syntax_error_unterm_str("${name}");
3919 debug_printf_parse("parse_dollar return 0: unterminated ${name}\n");
3922 nommu_addchr(as_string, ch);
3925 /* It's possible to just call add_till_closing_bracket() at this point.
3926 * However, this regresses some of our testsuite cases
3927 * which check invalid constructs like ${%}.
3928 * Oh well... let's check that the var name part is fine... */
3934 debug_printf_parse(": '%c'\n", ch);
3936 ch = i_getch(input);
3937 nommu_addchr(as_string, ch);
3941 if (!isalnum(ch) && ch != '_') {
3943 unsigned char last_ch;
3944 /* handle parameter expansions
3945 * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_06_02
3947 if (!strchr(VAR_SUBST_OPS, ch)) /* ${var<bad_char>... */
3948 goto bad_dollar_syntax;
3950 /* Eat everything until closing '}' (or ':') */
3952 if (ENABLE_HUSH_BASH_COMPAT
3954 && !strchr(MINUS_PLUS_EQUAL_QUESTION, i_peek(input))
3956 /* It's ${var:N[:M]} thing */
3957 end_ch = '}' * 0x100 + ':';
3959 if (ENABLE_HUSH_BASH_COMPAT
3962 /* It's ${var/[/]pattern[/repl]} thing */
3963 if (i_peek(input) == '/') { /* ${var//pattern[/repl]}? */
3965 nommu_addchr(as_string, '/');
3968 end_ch = '}' * 0x100 + '/';
3974 #if ENABLE_HUSH_DOLLAR_OPS
3975 last_ch = add_till_closing_bracket(dest, input, end_ch);
3976 if (last_ch == 0) /* error? */
3979 #error Simple code to only allow ${var} is not implemented
3982 o_addstr(as_string, dest->data + pos);
3983 o_addchr(as_string, last_ch);
3986 if (ENABLE_HUSH_BASH_COMPAT && (end_ch & 0xff00)) {
3987 /* close the first block: */
3988 o_addchr(dest, SPECIAL_VAR_SYMBOL);
3989 /* while parsing N from ${var:N[:M]}
3990 * or pattern from ${var/[/]pattern[/repl]} */
3991 if ((end_ch & 0xff) == last_ch) {
3992 /* got ':' or '/'- parse the rest */
3997 if (end_ch == '}' * 0x100 + ':') {
3998 /* it's ${var:N} - emulate :999999999 */
3999 o_addstr(dest, "999999999");
4000 } /* else: it's ${var/[/]pattern} */
4005 o_addchr(dest, SPECIAL_VAR_SYMBOL);
4008 #if ENABLE_SH_MATH_SUPPORT || ENABLE_HUSH_TICK
4012 ch = i_getch(input);
4013 nommu_addchr(as_string, ch);
4014 # if ENABLE_SH_MATH_SUPPORT
4015 if (i_peek(input) == '(') {
4016 ch = i_getch(input);
4017 nommu_addchr(as_string, ch);
4018 o_addchr(dest, SPECIAL_VAR_SYMBOL);
4019 o_addchr(dest, /*quote_mask |*/ '+');
4022 if (!add_till_closing_bracket(dest, input, ')' | DOUBLE_CLOSE_CHAR_FLAG))
4023 return 0; /* error */
4025 o_addstr(as_string, dest->data + pos);
4026 o_addchr(as_string, ')');
4027 o_addchr(as_string, ')');
4029 o_addchr(dest, SPECIAL_VAR_SYMBOL);
4033 # if ENABLE_HUSH_TICK
4034 o_addchr(dest, SPECIAL_VAR_SYMBOL);
4035 o_addchr(dest, quote_mask | '`');
4038 if (!add_till_closing_bracket(dest, input, ')'))
4039 return 0; /* error */
4041 o_addstr(as_string, dest->data + pos);
4042 o_addchr(as_string, ')');
4044 o_addchr(dest, SPECIAL_VAR_SYMBOL);
4050 ch = i_getch(input);
4051 nommu_addchr(as_string, ch);
4053 if (isalnum(ch)) { /* it's $_name or $_123 */
4058 /* TODO: $_ and $-: */
4059 /* $_ Shell or shell script name; or last argument of last command
4060 * (if last command wasn't a pipe; if it was, bash sets $_ to "");
4061 * but in command's env, set to full pathname used to invoke it */
4062 /* $- Option flags set by set builtin or shell options (-i etc) */
4064 o_addQchr(dest, '$');
4066 debug_printf_parse("parse_dollar return 1 (ok)\n");
4072 # if ENABLE_HUSH_BASH_COMPAT
4073 #define encode_string(as_string, dest, input, dquote_end, process_bkslash) \
4074 encode_string(dest, input, dquote_end, process_bkslash)
4076 /* only ${var/pattern/repl} (its pattern part) needs additional mode */
4077 #define encode_string(as_string, dest, input, dquote_end, process_bkslash) \
4078 encode_string(dest, input, dquote_end)
4080 #define as_string NULL
4084 # if ENABLE_HUSH_BASH_COMPAT
4085 /* all parameters are needed, no macro tricks */
4087 #define encode_string(as_string, dest, input, dquote_end, process_bkslash) \
4088 encode_string(as_string, dest, input, dquote_end)
4091 static int encode_string(o_string *as_string,
4093 struct in_str *input,
4095 int process_bkslash)
4097 #if !ENABLE_HUSH_BASH_COMPAT
4098 const int process_bkslash = 1;
4104 ch = i_getch(input);
4106 nommu_addchr(as_string, ch);
4107 if (ch == dquote_end) { /* may be only '"' or EOF */
4108 debug_printf_parse("encode_string return 1 (ok)\n");
4111 /* note: can't move it above ch == dquote_end check! */
4113 syntax_error_unterm_ch('"');
4114 return 0; /* error */
4118 next = i_peek(input);
4120 debug_printf_parse("\" ch=%c (%d) escape=%d\n",
4121 ch, ch, !!(dest->o_expflags & EXP_FLAG_ESC_GLOB_CHARS));
4122 if (process_bkslash && ch == '\\') {
4124 syntax_error("\\<eof>");
4128 * "The backslash retains its special meaning [in "..."]
4129 * only when followed by one of the following characters:
4130 * $, `, ", \, or <newline>. A double quote may be quoted
4131 * within double quotes by preceding it with a backslash."
4132 * NB: in (unquoted) heredoc, above does not apply to ",
4133 * therefore we check for it by "next == dquote_end" cond.
4135 if (next == dquote_end || strchr("$`\\\n", next)) {
4136 ch = i_getch(input); /* eat next */
4138 goto again; /* skip \<newline> */
4139 } /* else: ch remains == '\\', and we double it below: */
4140 o_addqchr(dest, ch); /* \c if c is a glob char, else just c */
4141 nommu_addchr(as_string, ch);
4145 if (!parse_dollar(as_string, dest, input, /*quote_mask:*/ 0x80)) {
4146 debug_printf_parse("encode_string return 0: "
4147 "parse_dollar returned 0 (error)\n");
4152 #if ENABLE_HUSH_TICK
4154 //unsigned pos = dest->length;
4155 o_addchr(dest, SPECIAL_VAR_SYMBOL);
4156 o_addchr(dest, 0x80 | '`');
4157 if (!add_till_backquote(dest, input, /*in_dquote:*/ dquote_end == '"'))
4158 return 0; /* error */
4159 o_addchr(dest, SPECIAL_VAR_SYMBOL);
4160 //debug_printf_subst("SUBST RES3 '%s'\n", dest->data + pos);
4164 o_addQchr(dest, ch);
4170 * Scan input until EOF or end_trigger char.
4171 * Return a list of pipes to execute, or NULL on EOF
4172 * or if end_trigger character is met.
4173 * On syntax error, exit if shell is not interactive,
4174 * reset parsing machinery and start parsing anew,
4175 * or return ERR_PTR.
4177 static struct pipe *parse_stream(char **pstring,
4178 struct in_str *input,
4181 struct parse_context ctx;
4182 o_string dest = NULL_O_STRING;
4185 /* Single-quote triggers a bypass of the main loop until its mate is
4186 * found. When recursing, quote state is passed in via dest->o_expflags.
4188 debug_printf_parse("parse_stream entered, end_trigger='%c'\n",
4189 end_trigger ? end_trigger : 'X');
4192 /* If very first arg is "" or '', dest.data may end up NULL.
4193 * Preventing this: */
4194 o_addchr(&dest, '\0');
4197 /* We used to separate words on $IFS here. This was wrong.
4198 * $IFS is used only for word splitting when $var is expanded,
4199 * here we should use blank chars as separators, not $IFS
4202 if (MAYBE_ASSIGNMENT != 0)
4203 dest.o_assignment = MAYBE_ASSIGNMENT;
4204 initialize_context(&ctx);
4207 const char *is_blank;
4208 const char *is_special;
4212 redir_type redir_style;
4214 ch = i_getch(input);
4215 debug_printf_parse(": ch=%c (%d) escape=%d\n",
4216 ch, ch, !!(dest.o_expflags & EXP_FLAG_ESC_GLOB_CHARS));
4221 syntax_error_unterm_str("here document");
4224 /* end_trigger == '}' case errors out earlier,
4225 * checking only ')' */
4226 if (end_trigger == ')') {
4227 syntax_error_unterm_ch('(');
4231 if (done_word(&dest, &ctx)) {
4235 done_pipe(&ctx, PIPE_SEQ);
4237 /* If we got nothing... */
4238 /* (this makes bare "&" cmd a no-op.
4239 * bash says: "syntax error near unexpected token '&'") */
4240 if (pi->num_cmds == 0
4241 IF_HAS_KEYWORDS(&& pi->res_word == RES_NONE)
4247 debug_printf_parse("as_string '%s'\n", ctx.as_string.data);
4249 *pstring = ctx.as_string.data;
4251 o_free_unsafe(&ctx.as_string);
4254 debug_printf_parse("parse_stream return %p\n", pi);
4257 nommu_addchr(&ctx.as_string, ch);
4261 next = i_peek(input);
4263 is_special = "{}<>;&|()#'" /* special outside of "str" */
4264 "\\$\"" IF_HUSH_TICK("`"); /* always special */
4265 /* Are { and } special here? */
4266 if (ctx.command->argv /* word [word]{... - non-special */
4267 || dest.length /* word{... - non-special */
4268 || dest.has_quoted_part /* ""{... - non-special */
4269 || (next != ';' /* }; - special */
4270 && next != ')' /* }) - special */
4271 && next != '&' /* }& and }&& ... - special */
4272 && next != '|' /* }|| ... - special */
4273 && !strchr(defifs, next) /* {word - non-special */
4276 /* They are not special, skip "{}" */
4279 is_special = strchr(is_special, ch);
4280 is_blank = strchr(defifs, ch);
4282 if (!is_special && !is_blank) { /* ordinary char */
4284 o_addQchr(&dest, ch);
4285 if ((dest.o_assignment == MAYBE_ASSIGNMENT
4286 || dest.o_assignment == WORD_IS_KEYWORD)
4288 && is_well_formed_var_name(dest.data, '=')
4290 dest.o_assignment = DEFINITELY_ASSIGNMENT;
4291 debug_printf_parse("dest.o_assignment='%s'\n", assignment_flag[dest.o_assignment]);
4297 if (done_word(&dest, &ctx)) {
4301 /* Is this a case when newline is simply ignored?
4303 * "cmd | <newline> cmd ..."
4304 * "case ... in <newline> word) ..."
4306 if (IS_NULL_CMD(ctx.command)
4307 && dest.length == 0 && !dest.has_quoted_part
4309 /* This newline can be ignored. But...
4310 * Without check #1, interactive shell
4311 * ignores even bare <newline>,
4312 * and shows the continuation prompt:
4313 * ps1_prompt$ <enter>
4314 * ps2> _ <=== wrong, should be ps1
4315 * Without check #2, "cmd & <newline>"
4316 * is similarly mistreated.
4317 * (BTW, this makes "cmd & cmd"
4318 * and "cmd && cmd" non-orthogonal.
4319 * Really, ask yourself, why
4320 * "cmd && <newline>" doesn't start
4321 * cmd but waits for more input?
4324 struct pipe *pi = ctx.list_head;
4325 if (pi->num_cmds != 0 /* check #1 */
4326 && pi->followup != PIPE_BG /* check #2 */
4331 /* Treat newline as a command separator. */
4332 done_pipe(&ctx, PIPE_SEQ);
4333 debug_printf_parse("heredoc_cnt:%d\n", heredoc_cnt);
4335 if (fetch_heredocs(heredoc_cnt, &ctx, input)) {
4340 dest.o_assignment = MAYBE_ASSIGNMENT;
4341 debug_printf_parse("dest.o_assignment='%s'\n", assignment_flag[dest.o_assignment]);
4343 /* note: if (is_blank) continue;
4344 * will still trigger for us */
4348 /* "cmd}" or "cmd }..." without semicolon or &:
4349 * } is an ordinary char in this case, even inside { cmd; }
4350 * Pathological example: { ""}; } should exec "}" cmd
4353 if (!IS_NULL_CMD(ctx.command) /* cmd } */
4354 || dest.length != 0 /* word} */
4355 || dest.has_quoted_part /* ""} */
4359 if (!IS_NULL_PIPE(ctx.pipe)) /* cmd | } */
4360 goto skip_end_trigger;
4361 /* else: } does terminate a group */
4364 if (end_trigger && end_trigger == ch
4365 && (ch != ';' || heredoc_cnt == 0)
4366 #if ENABLE_HUSH_CASE
4368 || ctx.ctx_res_w != RES_MATCH
4369 || (!dest.has_quoted_part && strcmp(dest.data, "esac") == 0)
4374 /* This is technically valid:
4375 * { cat <<HERE; }; echo Ok
4379 * but we don't support this.
4380 * We require heredoc to be in enclosing {}/(),
4383 syntax_error_unterm_str("here document");
4386 if (done_word(&dest, &ctx)) {
4389 done_pipe(&ctx, PIPE_SEQ);
4390 dest.o_assignment = MAYBE_ASSIGNMENT;
4391 debug_printf_parse("dest.o_assignment='%s'\n", assignment_flag[dest.o_assignment]);
4392 /* Do we sit outside of any if's, loops or case's? */
4394 IF_HAS_KEYWORDS(|| (ctx.ctx_res_w == RES_NONE && ctx.old_flag == 0))
4398 debug_printf_parse("as_string '%s'\n", ctx.as_string.data);
4400 *pstring = ctx.as_string.data;
4402 o_free_unsafe(&ctx.as_string);
4405 debug_printf_parse("parse_stream return %p: "
4406 "end_trigger char found\n",
4408 return ctx.list_head;
4415 /* Catch <, > before deciding whether this word is
4416 * an assignment. a=1 2>z b=2: b=2 is still assignment */
4419 redir_fd = redirect_opt_num(&dest);
4420 if (done_word(&dest, &ctx)) {
4423 redir_style = REDIRECT_OVERWRITE;
4425 redir_style = REDIRECT_APPEND;
4426 ch = i_getch(input);
4427 nommu_addchr(&ctx.as_string, ch);
4430 else if (next == '(') {
4431 syntax_error(">(process) not supported");
4435 if (parse_redirect(&ctx, redir_fd, redir_style, input))
4437 continue; /* back to top of while (1) */
4439 redir_fd = redirect_opt_num(&dest);
4440 if (done_word(&dest, &ctx)) {
4443 redir_style = REDIRECT_INPUT;
4445 redir_style = REDIRECT_HEREDOC;
4447 debug_printf_parse("++heredoc_cnt=%d\n", heredoc_cnt);
4448 ch = i_getch(input);
4449 nommu_addchr(&ctx.as_string, ch);
4450 } else if (next == '>') {
4451 redir_style = REDIRECT_IO;
4452 ch = i_getch(input);
4453 nommu_addchr(&ctx.as_string, ch);
4456 else if (next == '(') {
4457 syntax_error("<(process) not supported");
4461 if (parse_redirect(&ctx, redir_fd, redir_style, input))
4463 continue; /* back to top of while (1) */
4465 if (dest.length == 0 && !dest.has_quoted_part) {
4466 /* skip "#comment" */
4469 if (ch == EOF || ch == '\n')
4472 /* note: we do not add it to &ctx.as_string */
4474 nommu_addchr(&ctx.as_string, '\n');
4475 continue; /* back to top of while (1) */
4480 /* It's "\<newline>" */
4482 /* Remove trailing '\' from ctx.as_string */
4483 ctx.as_string.data[--ctx.as_string.length] = '\0';
4485 ch = i_getch(input); /* eat it */
4486 continue; /* back to top of while (1) */
4491 if (dest.o_assignment == MAYBE_ASSIGNMENT
4492 /* check that we are not in word in "a=1 2>word b=1": */
4493 && !ctx.pending_redirect
4495 /* ch is a special char and thus this word
4496 * cannot be an assignment */
4497 dest.o_assignment = NOT_ASSIGNMENT;
4498 debug_printf_parse("dest.o_assignment='%s'\n", assignment_flag[dest.o_assignment]);
4501 /* Note: nommu_addchr(&ctx.as_string, ch) is already done */
4504 case '#': /* non-comment #: "echo a#b" etc */
4505 o_addQchr(&dest, ch);
4509 syntax_error("\\<eof>");
4512 ch = i_getch(input);
4513 /* note: ch != '\n' (that case does not reach this place) */
4514 o_addchr(&dest, '\\');
4515 /*nommu_addchr(&ctx.as_string, '\\'); - already done */
4516 o_addchr(&dest, ch);
4517 nommu_addchr(&ctx.as_string, ch);
4518 /* Example: echo Hello \2>file
4519 * we need to know that word 2 is quoted */
4520 dest.has_quoted_part = 1;
4523 if (!parse_dollar(&ctx.as_string, &dest, input, /*quote_mask:*/ 0)) {
4524 debug_printf_parse("parse_stream parse error: "
4525 "parse_dollar returned 0 (error)\n");
4530 dest.has_quoted_part = 1;
4531 if (next == '\'' && !ctx.pending_redirect) {
4532 insert_empty_quoted_str_marker:
4533 nommu_addchr(&ctx.as_string, next);
4534 i_getch(input); /* eat second ' */
4535 o_addchr(&dest, SPECIAL_VAR_SYMBOL);
4536 o_addchr(&dest, SPECIAL_VAR_SYMBOL);
4539 ch = i_getch(input);
4541 syntax_error_unterm_ch('\'');
4544 nommu_addchr(&ctx.as_string, ch);
4547 o_addqchr(&dest, ch);
4552 dest.has_quoted_part = 1;
4553 if (next == '"' && !ctx.pending_redirect)
4554 goto insert_empty_quoted_str_marker;
4555 if (dest.o_assignment == NOT_ASSIGNMENT)
4556 dest.o_expflags |= EXP_FLAG_ESC_GLOB_CHARS;
4557 if (!encode_string(&ctx.as_string, &dest, input, '"', /*process_bkslash:*/ 1))
4559 dest.o_expflags &= ~EXP_FLAG_ESC_GLOB_CHARS;
4561 #if ENABLE_HUSH_TICK
4563 USE_FOR_NOMMU(unsigned pos;)
4565 o_addchr(&dest, SPECIAL_VAR_SYMBOL);
4566 o_addchr(&dest, '`');
4567 USE_FOR_NOMMU(pos = dest.length;)
4568 if (!add_till_backquote(&dest, input, /*in_dquote:*/ 0))
4571 o_addstr(&ctx.as_string, dest.data + pos);
4572 o_addchr(&ctx.as_string, '`');
4574 o_addchr(&dest, SPECIAL_VAR_SYMBOL);
4575 //debug_printf_subst("SUBST RES3 '%s'\n", dest.data + pos);
4580 #if ENABLE_HUSH_CASE
4583 if (done_word(&dest, &ctx)) {
4586 done_pipe(&ctx, PIPE_SEQ);
4587 #if ENABLE_HUSH_CASE
4588 /* Eat multiple semicolons, detect
4589 * whether it means something special */
4594 ch = i_getch(input);
4595 nommu_addchr(&ctx.as_string, ch);
4596 if (ctx.ctx_res_w == RES_CASE_BODY) {
4597 ctx.ctx_dsemicolon = 1;
4598 ctx.ctx_res_w = RES_MATCH;
4604 /* We just finished a cmd. New one may start
4605 * with an assignment */
4606 dest.o_assignment = MAYBE_ASSIGNMENT;
4607 debug_printf_parse("dest.o_assignment='%s'\n", assignment_flag[dest.o_assignment]);
4610 if (done_word(&dest, &ctx)) {
4614 ch = i_getch(input);
4615 nommu_addchr(&ctx.as_string, ch);
4616 done_pipe(&ctx, PIPE_AND);
4618 done_pipe(&ctx, PIPE_BG);
4622 if (done_word(&dest, &ctx)) {
4625 #if ENABLE_HUSH_CASE
4626 if (ctx.ctx_res_w == RES_MATCH)
4627 break; /* we are in case's "word | word)" */
4629 if (next == '|') { /* || */
4630 ch = i_getch(input);
4631 nommu_addchr(&ctx.as_string, ch);
4632 done_pipe(&ctx, PIPE_OR);
4634 /* we could pick up a file descriptor choice here
4635 * with redirect_opt_num(), but bash doesn't do it.
4636 * "echo foo 2| cat" yields "foo 2". */
4639 o_reset_to_empty_unquoted(&ctx.as_string);
4644 #if ENABLE_HUSH_CASE
4645 /* "case... in [(]word)..." - skip '(' */
4646 if (ctx.ctx_res_w == RES_MATCH
4647 && ctx.command->argv == NULL /* not (word|(... */
4648 && dest.length == 0 /* not word(... */
4649 && dest.has_quoted_part == 0 /* not ""(... */
4655 if (parse_group(&dest, &ctx, input, ch) != 0) {
4660 #if ENABLE_HUSH_CASE
4661 if (ctx.ctx_res_w == RES_MATCH)
4665 /* proper use of this character is caught by end_trigger:
4666 * if we see {, we call parse_group(..., end_trigger='}')
4667 * and it will match } earlier (not here). */
4668 syntax_error_unexpected_ch(ch);
4672 bb_error_msg_and_die("BUG: unexpected %c\n", ch);
4678 struct parse_context *pctx;
4679 IF_HAS_KEYWORDS(struct parse_context *p2;)
4681 /* Clean up allocated tree.
4682 * Sample for finding leaks on syntax error recovery path.
4683 * Run it from interactive shell, watch pmap `pidof hush`.
4684 * while if false; then false; fi; do break; fi
4685 * Samples to catch leaks at execution:
4686 * while if (true | {true;}); then echo ok; fi; do break; done
4687 * while if (true | {true;}); then echo ok; fi; do (if echo ok; break; then :; fi) | cat; break; done
4691 /* Update pipe/command counts,
4692 * otherwise freeing may miss some */
4693 done_pipe(pctx, PIPE_SEQ);
4694 debug_printf_clean("freeing list %p from ctx %p\n",
4695 pctx->list_head, pctx);
4696 debug_print_tree(pctx->list_head, 0);
4697 free_pipe_list(pctx->list_head);
4698 debug_printf_clean("freed list %p\n", pctx->list_head);
4700 o_free_unsafe(&pctx->as_string);
4702 IF_HAS_KEYWORDS(p2 = pctx->stack;)
4706 IF_HAS_KEYWORDS(pctx = p2;)
4707 } while (HAS_KEYWORDS && pctx);
4710 G.last_exitcode = 1;
4721 /*** Execution routines ***/
4723 /* Expansion can recurse, need forward decls: */
4724 #if !ENABLE_HUSH_BASH_COMPAT
4725 /* only ${var/pattern/repl} (its pattern part) needs additional mode */
4726 #define expand_string_to_string(str, do_unbackslash) \
4727 expand_string_to_string(str)
4729 static char *expand_string_to_string(const char *str, int do_unbackslash);
4730 #if ENABLE_HUSH_TICK
4731 static int process_command_subs(o_string *dest, const char *s);
4734 /* expand_strvec_to_strvec() takes a list of strings, expands
4735 * all variable references within and returns a pointer to
4736 * a list of expanded strings, possibly with larger number
4737 * of strings. (Think VAR="a b"; echo $VAR).
4738 * This new list is allocated as a single malloc block.
4739 * NULL-terminated list of char* pointers is at the beginning of it,
4740 * followed by strings themselves.
4741 * Caller can deallocate entire list by single free(list). */
4743 /* A horde of its helpers come first: */
4745 static void o_addblock_duplicate_backslash(o_string *o, const char *str, int len)
4747 while (--len >= 0) {
4750 #if ENABLE_HUSH_BRACE_EXPANSION
4751 if (c == '{' || c == '}') {
4752 /* { -> \{, } -> \} */
4754 /* And now we want to add { or } and continue:
4757 * luckily, just falling throught achieves this.
4763 /* \z -> \\\z; \<eol> -> \\<eol> */
4768 o_addchr(o, *str++);
4774 /* Store given string, finalizing the word and starting new one whenever
4775 * we encounter IFS char(s). This is used for expanding variable values.
4776 * End-of-string does NOT finalize word: think about 'echo -$VAR-'.
4777 * Return in *ended_with_ifs:
4778 * 1 - ended with IFS char, else 0 (this includes case of empty str).
4780 static int expand_on_ifs(int *ended_with_ifs, o_string *output, int n, const char *str)
4782 int last_is_ifs = 0;
4787 if (!*str) /* EOL - do not finalize word */
4789 word_len = strcspn(str, G.ifs);
4791 /* We have WORD_LEN leading non-IFS chars */
4792 if (!(output->o_expflags & EXP_FLAG_GLOB)) {
4793 o_addblock(output, str, word_len);
4795 /* Protect backslashes against globbing up :)
4796 * Example: "v='\*'; echo b$v" prints "b\*"
4797 * (and does not try to glob on "*")
4799 o_addblock_duplicate_backslash(output, str, word_len);
4800 /*/ Why can't we do it easier? */
4801 /*o_addblock(output, str, word_len); - WRONG: "v='\*'; echo Z$v" prints "Z*" instead of "Z\*" */
4802 /*o_addqblock(output, str, word_len); - WRONG: "v='*'; echo Z$v" prints "Z*" instead of Z* files */
4806 if (!*str) /* EOL - do not finalize word */
4810 /* We know str here points to at least one IFS char */
4812 str += strspn(str, G.ifs); /* skip IFS chars */
4813 if (!*str) /* EOL - do not finalize word */
4816 /* Start new word... but not always! */
4817 /* Case "v=' a'; echo ''$v": we do need to finalize empty word: */
4818 if (output->has_quoted_part
4819 /* Case "v=' a'; echo $v":
4820 * here nothing precedes the space in $v expansion,
4821 * therefore we should not finish the word
4822 * (IOW: if there *is* word to finalize, only then do it):
4824 || (n > 0 && output->data[output->length - 1])
4826 o_addchr(output, '\0');
4827 debug_print_list("expand_on_ifs", output, n);
4828 n = o_save_ptr(output, n);
4833 *ended_with_ifs = last_is_ifs;
4834 debug_print_list("expand_on_ifs[1]", output, n);
4838 /* Helper to expand $((...)) and heredoc body. These act as if
4839 * they are in double quotes, with the exception that they are not :).
4840 * Just the rules are similar: "expand only $var and `cmd`"
4842 * Returns malloced string.
4843 * As an optimization, we return NULL if expansion is not needed.
4845 #if !ENABLE_HUSH_BASH_COMPAT
4846 /* only ${var/pattern/repl} (its pattern part) needs additional mode */
4847 #define encode_then_expand_string(str, process_bkslash, do_unbackslash) \
4848 encode_then_expand_string(str)
4850 static char *encode_then_expand_string(const char *str, int process_bkslash, int do_unbackslash)
4853 struct in_str input;
4854 o_string dest = NULL_O_STRING;
4856 if (!strchr(str, '$')
4857 && !strchr(str, '\\')
4858 #if ENABLE_HUSH_TICK
4859 && !strchr(str, '`')
4865 /* We need to expand. Example:
4866 * echo $(($a + `echo 1`)) $((1 + $((2)) ))
4868 setup_string_in_str(&input, str);
4869 encode_string(NULL, &dest, &input, EOF, process_bkslash);
4870 //TODO: error check (encode_string returns 0 on error)?
4871 //bb_error_msg("'%s' -> '%s'", str, dest.data);
4872 exp_str = expand_string_to_string(dest.data, /*unbackslash:*/ do_unbackslash);
4873 //bb_error_msg("'%s' -> '%s'", dest.data, exp_str);
4874 o_free_unsafe(&dest);
4878 #if ENABLE_SH_MATH_SUPPORT
4879 static arith_t expand_and_evaluate_arith(const char *arg, const char **errmsg_p)
4881 arith_state_t math_state;
4885 math_state.lookupvar = get_local_var_value;
4886 math_state.setvar = set_local_var_from_halves;
4887 //math_state.endofname = endofname;
4888 exp_str = encode_then_expand_string(arg, /*process_bkslash:*/ 1, /*unbackslash:*/ 1);
4889 res = arith(&math_state, exp_str ? exp_str : arg);
4892 *errmsg_p = math_state.errmsg;
4893 if (math_state.errmsg)
4894 die_if_script(math_state.errmsg);
4899 #if ENABLE_HUSH_BASH_COMPAT
4900 /* ${var/[/]pattern[/repl]} helpers */
4901 static char *strstr_pattern(char *val, const char *pattern, int *size)
4904 char *end = scan_and_match(val, pattern, SCAN_MOVE_FROM_RIGHT + SCAN_MATCH_LEFT_HALF);
4905 debug_printf_varexp("val:'%s' pattern:'%s' end:'%s'\n", val, pattern, end);
4912 /* Optimization: if "*pat" did not match the start of "string",
4913 * we know that "tring", "ring" etc will not match too:
4915 if (pattern[0] == '*')
4920 static char *replace_pattern(char *val, const char *pattern, const char *repl, char exp_op)
4922 char *result = NULL;
4923 unsigned res_len = 0;
4924 unsigned repl_len = strlen(repl);
4928 char *s = strstr_pattern(val, pattern, &size);
4932 result = xrealloc(result, res_len + (s - val) + repl_len + 1);
4933 memcpy(result + res_len, val, s - val);
4935 strcpy(result + res_len, repl);
4936 res_len += repl_len;
4937 debug_printf_varexp("val:'%s' s:'%s' result:'%s'\n", val, s, result);
4943 if (val[0] && result) {
4944 result = xrealloc(result, res_len + strlen(val) + 1);
4945 strcpy(result + res_len, val);
4946 debug_printf_varexp("val:'%s' result:'%s'\n", val, result);
4948 debug_printf_varexp("result:'%s'\n", result);
4954 * Handles <SPECIAL_VAR_SYMBOL>varname...<SPECIAL_VAR_SYMBOL> construct.
4956 static NOINLINE const char *expand_one_var(char **to_be_freed_pp, char *arg, char **pp)
4958 const char *val = NULL;
4959 char *to_be_freed = NULL;
4964 char exp_save = exp_save; /* for compiler */
4965 char *exp_saveptr; /* points to expansion operator */
4966 char *exp_word = exp_word; /* for compiler */
4969 *p = '\0'; /* replace trailing SPECIAL_VAR_SYMBOL */
4971 exp_saveptr = arg[1] ? strchr(VAR_ENCODED_SUBST_OPS, arg[1]) : NULL;
4973 first_char = arg[0] = arg0 & 0x7f;
4976 if (first_char == '#' /* ${#... */
4977 && arg[1] && !exp_saveptr /* not ${#} and not ${#<op_char>...} */
4979 /* It must be length operator: ${#var} */
4983 /* Maybe handle parameter expansion */
4984 if (exp_saveptr /* if 2nd char is one of expansion operators */
4985 && strchr(NUMERIC_SPECVARS_STR, first_char) /* 1st char is special variable */
4987 /* ${?:0}, ${#[:]%0} etc */
4988 exp_saveptr = var + 1;
4990 /* ${?}, ${var}, ${var:0}, ${var[:]%0} etc */
4991 exp_saveptr = var+1 + strcspn(var+1, VAR_ENCODED_SUBST_OPS);
4993 exp_op = exp_save = *exp_saveptr;
4995 exp_word = exp_saveptr + 1;
4996 if (exp_op == ':') {
4997 exp_op = *exp_word++;
4998 //TODO: try ${var:} and ${var:bogus} in non-bash config
4999 if (ENABLE_HUSH_BASH_COMPAT
5000 && (!exp_op || !strchr(MINUS_PLUS_EQUAL_QUESTION, exp_op))
5002 /* oops... it's ${var:N[:M]}, not ${var:?xxx} or some such */
5007 *exp_saveptr = '\0';
5008 } /* else: it's not an expansion op, but bare ${var} */
5011 /* Look up the variable in question */
5012 if (isdigit(var[0])) {
5013 /* parse_dollar should have vetted var for us */
5014 int n = xatoi_positive(var);
5015 if (n < G.global_argc)
5016 val = G.global_argv[n];
5017 /* else val remains NULL: $N with too big N */
5021 val = utoa(G.root_pid);
5023 case '!': /* bg pid */
5024 val = G.last_bg_pid ? utoa(G.last_bg_pid) : "";
5026 case '?': /* exitcode */
5027 val = utoa(G.last_exitcode);
5029 case '#': /* argc */
5030 val = utoa(G.global_argc ? G.global_argc-1 : 0);
5033 val = get_local_var_value(var);
5037 /* Handle any expansions */
5038 if (exp_op == 'L') {
5039 reinit_unicode_for_hush();
5040 debug_printf_expand("expand: length(%s)=", val);
5041 val = utoa(val ? unicode_strlen(val) : 0);
5042 debug_printf_expand("%s\n", val);
5043 } else if (exp_op) {
5044 if (exp_op == '%' || exp_op == '#') {
5045 /* Standard-mandated substring removal ops:
5046 * ${parameter%word} - remove smallest suffix pattern
5047 * ${parameter%%word} - remove largest suffix pattern
5048 * ${parameter#word} - remove smallest prefix pattern
5049 * ${parameter##word} - remove largest prefix pattern
5051 * Word is expanded to produce a glob pattern.
5052 * Then var's value is matched to it and matching part removed.
5054 if (val && val[0]) {
5058 unsigned scan_flags = pick_scan(exp_op, *exp_word);
5059 if (exp_op == *exp_word) /* ## or %% */
5061 exp_exp_word = encode_then_expand_string(exp_word, /*process_bkslash:*/ 1, /*unbackslash:*/ 1);
5063 exp_word = exp_exp_word;
5064 /* HACK ALERT. We depend here on the fact that
5065 * G.global_argv and results of utoa and get_local_var_value
5066 * are actually in writable memory:
5067 * scan_and_match momentarily stores NULs there. */
5069 loc = scan_and_match(t, exp_word, scan_flags);
5070 //bb_error_msg("op:%c str:'%s' pat:'%s' res:'%s'",
5071 // exp_op, t, exp_word, loc);
5073 if (loc) { /* match was found */
5074 if (scan_flags & SCAN_MATCH_LEFT_HALF) /* #[#] */
5075 val = loc; /* take right part */
5077 val = to_be_freed = xstrndup(val, loc - val); /* left */
5081 #if ENABLE_HUSH_BASH_COMPAT
5082 else if (exp_op == '/' || exp_op == '\\') {
5083 /* It's ${var/[/]pattern[/repl]} thing.
5084 * Note that in encoded form it has TWO parts:
5085 * var/pattern<SPECIAL_VAR_SYMBOL>repl<SPECIAL_VAR_SYMBOL>
5086 * and if // is used, it is encoded as \:
5087 * var\pattern<SPECIAL_VAR_SYMBOL>repl<SPECIAL_VAR_SYMBOL>
5089 /* Empty variable always gives nothing: */
5090 // "v=''; echo ${v/*/w}" prints "", not "w"
5091 if (val && val[0]) {
5092 /* pattern uses non-standard expansion.
5093 * repl should be unbackslashed and globbed
5094 * by the usual expansion rules:
5096 * v='a bz'; echo "${v/a*z/a*z}" prints "a*z"
5097 * v='a bz'; echo "${v/a*z/\z}" prints "\z"
5098 * v='a bz'; echo ${v/a*z/a*z} prints "az"
5099 * v='a bz'; echo ${v/a*z/\z} prints "z"
5100 * (note that a*z _pattern_ is never globbed!)
5102 char *pattern, *repl, *t;
5103 pattern = encode_then_expand_string(exp_word, /*process_bkslash:*/ 0, /*unbackslash:*/ 0);
5105 pattern = xstrdup(exp_word);
5106 debug_printf_varexp("pattern:'%s'->'%s'\n", exp_word, pattern);
5107 *p++ = SPECIAL_VAR_SYMBOL;
5109 p = strchr(p, SPECIAL_VAR_SYMBOL);
5111 repl = encode_then_expand_string(exp_word, /*process_bkslash:*/ arg0 & 0x80, /*unbackslash:*/ 1);
5112 debug_printf_varexp("repl:'%s'->'%s'\n", exp_word, repl);
5113 /* HACK ALERT. We depend here on the fact that
5114 * G.global_argv and results of utoa and get_local_var_value
5115 * are actually in writable memory:
5116 * replace_pattern momentarily stores NULs there. */
5118 to_be_freed = replace_pattern(t,
5120 (repl ? repl : exp_word),
5122 if (to_be_freed) /* at least one replace happened */
5129 else if (exp_op == ':') {
5130 #if ENABLE_HUSH_BASH_COMPAT && ENABLE_SH_MATH_SUPPORT
5131 /* It's ${var:N[:M]} bashism.
5132 * Note that in encoded form it has TWO parts:
5133 * var:N<SPECIAL_VAR_SYMBOL>M<SPECIAL_VAR_SYMBOL>
5138 beg = expand_and_evaluate_arith(exp_word, &errmsg);
5141 debug_printf_varexp("beg:'%s'=%lld\n", exp_word, (long long)beg);
5142 *p++ = SPECIAL_VAR_SYMBOL;
5144 p = strchr(p, SPECIAL_VAR_SYMBOL);
5146 len = expand_and_evaluate_arith(exp_word, &errmsg);
5149 debug_printf_varexp("len:'%s'=%lld\n", exp_word, (long long)len);
5150 if (len >= 0) { /* bash compat: len < 0 is illegal */
5151 if (beg < 0) /* bash compat */
5153 debug_printf_varexp("from val:'%s'\n", val);
5154 if (len == 0 || !val || beg >= strlen(val)) {
5158 /* Paranoia. What if user entered 9999999999999
5159 * which fits in arith_t but not int? */
5162 val = to_be_freed = xstrndup(val + beg, len);
5164 debug_printf_varexp("val:'%s'\n", val);
5168 die_if_script("malformed ${%s:...}", var);
5171 } else { /* one of "-=+?" */
5172 /* Standard-mandated substitution ops:
5173 * ${var?word} - indicate error if unset
5174 * If var is unset, word (or a message indicating it is unset
5175 * if word is null) is written to standard error
5176 * and the shell exits with a non-zero exit status.
5177 * Otherwise, the value of var is substituted.
5178 * ${var-word} - use default value
5179 * If var is unset, word is substituted.
5180 * ${var=word} - assign and use default value
5181 * If var is unset, word is assigned to var.
5182 * In all cases, final value of var is substituted.
5183 * ${var+word} - use alternative value
5184 * If var is unset, null is substituted.
5185 * Otherwise, word is substituted.
5187 * Word is subjected to tilde expansion, parameter expansion,
5188 * command substitution, and arithmetic expansion.
5189 * If word is not needed, it is not expanded.
5191 * Colon forms (${var:-word}, ${var:=word} etc) do the same,
5192 * but also treat null var as if it is unset.
5194 int use_word = (!val || ((exp_save == ':') && !val[0]));
5196 use_word = !use_word;
5197 debug_printf_expand("expand: op:%c (null:%s) test:%i\n", exp_op,
5198 (exp_save == ':') ? "true" : "false", use_word);
5200 to_be_freed = encode_then_expand_string(exp_word, /*process_bkslash:*/ 1, /*unbackslash:*/ 1);
5202 exp_word = to_be_freed;
5203 if (exp_op == '?') {
5204 /* mimic bash message */
5205 die_if_script("%s: %s",
5207 exp_word[0] ? exp_word : "parameter null or not set"
5209 //TODO: how interactive bash aborts expansion mid-command?
5214 if (exp_op == '=') {
5215 /* ${var=[word]} or ${var:=[word]} */
5216 if (isdigit(var[0]) || var[0] == '#') {
5217 /* mimic bash message */
5218 die_if_script("$%s: cannot assign in this way", var);
5221 char *new_var = xasprintf("%s=%s", var, val);
5222 set_local_var(new_var, /*exp:*/ 0, /*lvl:*/ 0, /*ro:*/ 0);
5226 } /* one of "-=+?" */
5228 *exp_saveptr = exp_save;
5234 *to_be_freed_pp = to_be_freed;
5238 /* Expand all variable references in given string, adding words to list[]
5239 * at n, n+1,... positions. Return updated n (so that list[n] is next one
5240 * to be filled). This routine is extremely tricky: has to deal with
5241 * variables/parameters with whitespace, $* and $@, and constructs like
5242 * 'echo -$*-'. If you play here, you must run testsuite afterwards! */
5243 static NOINLINE int expand_vars_to_list(o_string *output, int n, char *arg)
5245 /* output->o_expflags & EXP_FLAG_SINGLEWORD (0x80) if we are in
5246 * expansion of right-hand side of assignment == 1-element expand.
5248 char cant_be_null = 0; /* only bit 0x80 matters */
5249 int ended_in_ifs = 0; /* did last unquoted expansion end with IFS chars? */
5252 debug_printf_expand("expand_vars_to_list: arg:'%s' singleword:%x\n", arg,
5253 !!(output->o_expflags & EXP_FLAG_SINGLEWORD));
5254 debug_print_list("expand_vars_to_list", output, n);
5255 n = o_save_ptr(output, n);
5256 debug_print_list("expand_vars_to_list[0]", output, n);
5258 while ((p = strchr(arg, SPECIAL_VAR_SYMBOL)) != NULL) {
5260 char *to_be_freed = NULL;
5261 const char *val = NULL;
5262 #if ENABLE_HUSH_TICK
5263 o_string subst_result = NULL_O_STRING;
5265 #if ENABLE_SH_MATH_SUPPORT
5266 char arith_buf[sizeof(arith_t)*3 + 2];
5270 o_addchr(output, '\0');
5271 n = o_save_ptr(output, n);
5275 o_addblock(output, arg, p - arg);
5276 debug_print_list("expand_vars_to_list[1]", output, n);
5278 p = strchr(p, SPECIAL_VAR_SYMBOL);
5280 /* Fetch special var name (if it is indeed one of them)
5281 * and quote bit, force the bit on if singleword expansion -
5282 * important for not getting v=$@ expand to many words. */
5283 first_ch = arg[0] | (output->o_expflags & EXP_FLAG_SINGLEWORD);
5285 /* Is this variable quoted and thus expansion can't be null?
5286 * "$@" is special. Even if quoted, it can still
5287 * expand to nothing (not even an empty string),
5288 * thus it is excluded. */
5289 if ((first_ch & 0x7f) != '@')
5290 cant_be_null |= first_ch;
5292 switch (first_ch & 0x7f) {
5293 /* Highest bit in first_ch indicates that var is double-quoted */
5297 if (!G.global_argv[1])
5300 cant_be_null |= first_ch; /* do it for "$@" _now_, when we know it's not empty */
5301 if (!(first_ch & 0x80)) { /* unquoted $* or $@ */
5302 while (G.global_argv[i]) {
5303 n = expand_on_ifs(NULL, output, n, G.global_argv[i]);
5304 debug_printf_expand("expand_vars_to_list: argv %d (last %d)\n", i, G.global_argc - 1);
5305 if (G.global_argv[i++][0] && G.global_argv[i]) {
5306 /* this argv[] is not empty and not last:
5307 * put terminating NUL, start new word */
5308 o_addchr(output, '\0');
5309 debug_print_list("expand_vars_to_list[2]", output, n);
5310 n = o_save_ptr(output, n);
5311 debug_print_list("expand_vars_to_list[3]", output, n);
5315 /* If EXP_FLAG_SINGLEWORD, we handle assignment 'a=....$@.....'
5316 * and in this case should treat it like '$*' - see 'else...' below */
5317 if (first_ch == ('@'|0x80) /* quoted $@ */
5318 && !(output->o_expflags & EXP_FLAG_SINGLEWORD) /* not v="$@" case */
5321 o_addQstr(output, G.global_argv[i]);
5322 if (++i >= G.global_argc)
5324 o_addchr(output, '\0');
5325 debug_print_list("expand_vars_to_list[4]", output, n);
5326 n = o_save_ptr(output, n);
5328 } else { /* quoted $* (or v="$@" case): add as one word */
5330 o_addQstr(output, G.global_argv[i]);
5331 if (!G.global_argv[++i])
5334 o_addchr(output, G.ifs[0]);
5336 output->has_quoted_part = 1;
5340 case SPECIAL_VAR_SYMBOL: /* <SPECIAL_VAR_SYMBOL><SPECIAL_VAR_SYMBOL> */
5341 /* "Empty variable", used to make "" etc to not disappear */
5342 output->has_quoted_part = 1;
5344 cant_be_null = 0x80;
5346 #if ENABLE_HUSH_TICK
5347 case '`': /* <SPECIAL_VAR_SYMBOL>`cmd<SPECIAL_VAR_SYMBOL> */
5348 *p = '\0'; /* replace trailing <SPECIAL_VAR_SYMBOL> */
5350 /* Can't just stuff it into output o_string,
5351 * expanded result may need to be globbed
5352 * and $IFS-splitted */
5353 debug_printf_subst("SUBST '%s' first_ch %x\n", arg, first_ch);
5354 G.last_exitcode = process_command_subs(&subst_result, arg);
5355 debug_printf_subst("SUBST RES:%d '%s'\n", G.last_exitcode, subst_result.data);
5356 val = subst_result.data;
5359 #if ENABLE_SH_MATH_SUPPORT
5360 case '+': { /* <SPECIAL_VAR_SYMBOL>+cmd<SPECIAL_VAR_SYMBOL> */
5363 arg++; /* skip '+' */
5364 *p = '\0'; /* replace trailing <SPECIAL_VAR_SYMBOL> */
5365 debug_printf_subst("ARITH '%s' first_ch %x\n", arg, first_ch);
5366 res = expand_and_evaluate_arith(arg, NULL);
5367 debug_printf_subst("ARITH RES '"ARITH_FMT"'\n", res);
5368 sprintf(arith_buf, ARITH_FMT, res);
5374 val = expand_one_var(&to_be_freed, arg, &p);
5375 IF_HUSH_TICK(store_val:)
5376 if (!(first_ch & 0x80)) { /* unquoted $VAR */
5377 debug_printf_expand("unquoted '%s', output->o_escape:%d\n", val,
5378 !!(output->o_expflags & EXP_FLAG_ESC_GLOB_CHARS));
5379 if (val && val[0]) {
5380 n = expand_on_ifs(&ended_in_ifs, output, n, val);
5383 } else { /* quoted $VAR, val will be appended below */
5384 output->has_quoted_part = 1;
5385 debug_printf_expand("quoted '%s', output->o_escape:%d\n", val,
5386 !!(output->o_expflags & EXP_FLAG_ESC_GLOB_CHARS));
5390 } /* switch (char after <SPECIAL_VAR_SYMBOL>) */
5392 if (val && val[0]) {
5393 o_addQstr(output, val);
5397 /* Restore NULL'ed SPECIAL_VAR_SYMBOL.
5398 * Do the check to avoid writing to a const string. */
5399 if (*p != SPECIAL_VAR_SYMBOL)
5400 *p = SPECIAL_VAR_SYMBOL;
5402 #if ENABLE_HUSH_TICK
5403 o_free(&subst_result);
5406 } /* end of "while (SPECIAL_VAR_SYMBOL is found) ..." */
5410 o_addchr(output, '\0');
5411 n = o_save_ptr(output, n);
5413 debug_print_list("expand_vars_to_list[a]", output, n);
5414 /* this part is literal, and it was already pre-quoted
5415 * if needed (much earlier), do not use o_addQstr here! */
5416 o_addstr_with_NUL(output, arg);
5417 debug_print_list("expand_vars_to_list[b]", output, n);
5418 } else if (output->length == o_get_last_ptr(output, n) /* expansion is empty */
5419 && !(cant_be_null & 0x80) /* and all vars were not quoted. */
5422 /* allow to reuse list[n] later without re-growth */
5423 output->has_empty_slot = 1;
5425 o_addchr(output, '\0');
5431 static char **expand_variables(char **argv, unsigned expflags)
5435 o_string output = NULL_O_STRING;
5437 output.o_expflags = expflags;
5441 n = expand_vars_to_list(&output, n, *argv);
5444 debug_print_list("expand_variables", &output, n);
5446 /* output.data (malloced in one block) gets returned in "list" */
5447 list = o_finalize_list(&output, n);
5448 debug_print_strings("expand_variables[1]", list);
5452 static char **expand_strvec_to_strvec(char **argv)
5454 return expand_variables(argv, EXP_FLAG_GLOB | EXP_FLAG_ESC_GLOB_CHARS);
5457 #if ENABLE_HUSH_BASH_COMPAT
5458 static char **expand_strvec_to_strvec_singleword_noglob(char **argv)
5460 return expand_variables(argv, EXP_FLAG_SINGLEWORD);
5464 /* Used for expansion of right hand of assignments,
5465 * $((...)), heredocs, variable espansion parts.
5467 * NB: should NOT do globbing!
5468 * "export v=/bin/c*; env | grep ^v=" outputs "v=/bin/c*"
5470 static char *expand_string_to_string(const char *str, int do_unbackslash)
5472 #if !ENABLE_HUSH_BASH_COMPAT
5473 const int do_unbackslash = 1;
5475 char *argv[2], **list;
5477 debug_printf_expand("string_to_string<='%s'\n", str);
5478 /* This is generally an optimization, but it also
5479 * handles "", which otherwise trips over !list[0] check below.
5480 * (is this ever happens that we actually get str="" here?)
5482 if (!strchr(str, SPECIAL_VAR_SYMBOL) && !strchr(str, '\\')) {
5483 //TODO: Can use on strings with \ too, just unbackslash() them?
5484 debug_printf_expand("string_to_string(fast)=>'%s'\n", str);
5485 return xstrdup(str);
5488 argv[0] = (char*)str;
5490 list = expand_variables(argv, do_unbackslash
5491 ? EXP_FLAG_ESC_GLOB_CHARS | EXP_FLAG_SINGLEWORD
5492 : EXP_FLAG_SINGLEWORD
5495 if (!list[0] || list[1])
5496 bb_error_msg_and_die("BUG in varexp2");
5497 /* actually, just move string 2*sizeof(char*) bytes back */
5498 overlapping_strcpy((char*)list, list[0]);
5500 unbackslash((char*)list);
5501 debug_printf_expand("string_to_string=>'%s'\n", (char*)list);
5505 /* Used for "eval" builtin */
5506 static char* expand_strvec_to_string(char **argv)
5510 list = expand_variables(argv, EXP_FLAG_SINGLEWORD);
5511 /* Convert all NULs to spaces */
5516 if (list[n-1] + strlen(list[n-1]) + 1 != list[n])
5517 bb_error_msg_and_die("BUG in varexp3");
5518 /* bash uses ' ' regardless of $IFS contents */
5523 overlapping_strcpy((char*)list, list[0]);
5524 debug_printf_expand("strvec_to_string='%s'\n", (char*)list);
5528 static char **expand_assignments(char **argv, int count)
5533 G.expanded_assignments = p = NULL;
5534 /* Expand assignments into one string each */
5535 for (i = 0; i < count; i++) {
5536 G.expanded_assignments = p = add_string_to_strings(p, expand_string_to_string(argv[i], /*unbackslash:*/ 1));
5538 G.expanded_assignments = NULL;
5543 static void switch_off_special_sigs(unsigned mask)
5546 while ((mask >>= 1) != 0) {
5551 if (G.traps[sig] && !G.traps[sig][0])
5552 /* trap is '', has to remain SIG_IGN */
5555 G.traps[sig] = NULL;
5557 /* We are here only if no trap or trap was not '' */
5558 install_sighandler(sig, SIG_DFL);
5564 void re_execute_shell(char ***to_free, const char *s,
5565 char *g_argv0, char **g_argv,
5566 char **builtin_argv) NORETURN;
5568 static void reset_traps_to_defaults(void)
5570 /* This function is always called in a child shell
5571 * after fork (not vfork, NOMMU doesn't use this function).
5576 /* Child shells are not interactive.
5577 * SIGTTIN/SIGTTOU/SIGTSTP should not have special handling.
5578 * Testcase: (while :; do :; done) + ^Z should background.
5579 * Same goes for SIGTERM, SIGHUP, SIGINT.
5581 mask = (G.special_sig_mask & SPECIAL_INTERACTIVE_SIGS) | G_fatal_sig_mask;
5582 if (!G.traps && !mask)
5583 return; /* already no traps and no special sigs */
5585 /* Switch off special sigs */
5586 switch_off_special_sigs(mask);
5588 G_fatal_sig_mask = 0;
5590 G.special_sig_mask &= ~SPECIAL_INTERACTIVE_SIGS;
5591 /* SIGQUIT,SIGCHLD and maybe SPECIAL_JOBSTOP_SIGS
5592 * remain set in G.special_sig_mask */
5597 /* Reset all sigs to default except ones with empty traps */
5598 for (sig = 0; sig < NSIG; sig++) {
5600 continue; /* no trap: nothing to do */
5601 if (!G.traps[sig][0])
5602 continue; /* empty trap: has to remain SIG_IGN */
5603 /* sig has non-empty trap, reset it: */
5605 G.traps[sig] = NULL;
5606 /* There is no signal for trap 0 (EXIT) */
5609 install_sighandler(sig, pick_sighandler(sig));
5615 static void re_execute_shell(char ***to_free, const char *s,
5616 char *g_argv0, char **g_argv,
5617 char **builtin_argv) NORETURN;
5618 static void re_execute_shell(char ***to_free, const char *s,
5619 char *g_argv0, char **g_argv,
5620 char **builtin_argv)
5622 # define NOMMU_HACK_FMT ("-$%x:%x:%x:%x:%x:%llx" IF_HUSH_LOOPS(":%x"))
5623 /* delims + 2 * (number of bytes in printed hex numbers) */
5624 char param_buf[sizeof(NOMMU_HACK_FMT) + 2 * (sizeof(int)*6 + sizeof(long long)*1)];
5625 char *heredoc_argv[4];
5626 struct variable *cur;
5627 # if ENABLE_HUSH_FUNCTIONS
5628 struct function *funcp;
5632 unsigned long long empty_trap_mask;
5634 if (!g_argv0) { /* heredoc */
5635 argv = heredoc_argv;
5636 argv[0] = (char *) G.argv0_for_re_execing;
5637 argv[1] = (char *) "-<";
5638 argv[2] = (char *) s;
5640 pp = &argv[3]; /* used as pointer to empty environment */
5646 if (pp) while (*pp++)
5649 empty_trap_mask = 0;
5652 for (sig = 1; sig < NSIG; sig++) {
5653 if (G.traps[sig] && !G.traps[sig][0])
5654 empty_trap_mask |= 1LL << sig;
5658 sprintf(param_buf, NOMMU_HACK_FMT
5659 , (unsigned) G.root_pid
5660 , (unsigned) G.root_ppid
5661 , (unsigned) G.last_bg_pid
5662 , (unsigned) G.last_exitcode
5665 IF_HUSH_LOOPS(, G.depth_of_loop)
5667 # undef NOMMU_HACK_FMT
5668 /* 1:hush 2:-$<pid>:<pid>:<exitcode>:<etc...> <vars...> <funcs...>
5669 * 3:-c 4:<cmd> 5:<arg0> <argN...> 6:NULL
5672 for (cur = G.top_var; cur; cur = cur->next) {
5673 if (!cur->flg_export || cur->flg_read_only)
5676 # if ENABLE_HUSH_FUNCTIONS
5677 for (funcp = G.top_func; funcp; funcp = funcp->next)
5683 *to_free = argv = pp = xzalloc(sizeof(argv[0]) * cnt);
5684 *pp++ = (char *) G.argv0_for_re_execing;
5686 for (cur = G.top_var; cur; cur = cur->next) {
5687 if (strcmp(cur->varstr, hush_version_str) == 0)
5689 if (cur->flg_read_only) {
5690 *pp++ = (char *) "-R";
5691 *pp++ = cur->varstr;
5692 } else if (!cur->flg_export) {
5693 *pp++ = (char *) "-V";
5694 *pp++ = cur->varstr;
5697 # if ENABLE_HUSH_FUNCTIONS
5698 for (funcp = G.top_func; funcp; funcp = funcp->next) {
5699 *pp++ = (char *) "-F";
5700 *pp++ = funcp->name;
5701 *pp++ = funcp->body_as_string;
5704 /* We can pass activated traps here. Say, -Tnn:trap_string
5706 * However, POSIX says that subshells reset signals with traps
5708 * I tested bash-3.2 and it not only does that with true subshells
5709 * of the form ( list ), but with any forked children shells.
5710 * I set trap "echo W" WINCH; and then tried:
5712 * { echo 1; sleep 20; echo 2; } &
5713 * while true; do echo 1; sleep 20; echo 2; break; done &
5714 * true | { echo 1; sleep 20; echo 2; } | cat
5716 * In all these cases sending SIGWINCH to the child shell
5717 * did not run the trap. If I add trap "echo V" WINCH;
5718 * _inside_ group (just before echo 1), it works.
5720 * I conclude it means we don't need to pass active traps here.
5722 *pp++ = (char *) "-c";
5725 while (*++builtin_argv)
5726 *pp++ = *builtin_argv;
5727 *pp++ = (char *) "";
5732 /* *pp = NULL; - is already there */
5736 debug_printf_exec("re_execute_shell pid:%d cmd:'%s'\n", getpid(), s);
5737 /* Don't propagate SIG_IGN to the child */
5738 if (SPECIAL_JOBSTOP_SIGS != 0)
5739 switch_off_special_sigs(G.special_sig_mask & SPECIAL_JOBSTOP_SIGS);
5740 execve(bb_busybox_exec_path, argv, pp);
5741 /* Fallback. Useful for init=/bin/hush usage etc */
5742 if (argv[0][0] == '/')
5743 execve(argv[0], argv, pp);
5744 xfunc_error_retval = 127;
5745 bb_error_msg_and_die("can't re-execute the shell");
5747 #endif /* !BB_MMU */
5750 static int run_and_free_list(struct pipe *pi);
5752 /* Executing from string: eval, sh -c '...'
5753 * or from file: /etc/profile, . file, sh <script>, sh (intereactive)
5754 * end_trigger controls how often we stop parsing
5755 * NUL: parse all, execute, return
5756 * ';': parse till ';' or newline, execute, repeat till EOF
5758 static void parse_and_run_stream(struct in_str *inp, int end_trigger)
5760 /* Why we need empty flag?
5761 * An obscure corner case "false; ``; echo $?":
5762 * empty command in `` should still set $? to 0.
5763 * But we can't just set $? to 0 at the start,
5764 * this breaks "false; echo `echo $?`" case.
5768 struct pipe *pipe_list;
5770 #if ENABLE_HUSH_INTERACTIVE
5771 if (end_trigger == ';')
5772 inp->promptmode = 0; /* PS1 */
5774 pipe_list = parse_stream(NULL, inp, end_trigger);
5775 if (!pipe_list || pipe_list == ERR_PTR) { /* EOF/error */
5776 /* If we are in "big" script
5777 * (not in `cmd` or something similar)...
5779 if (pipe_list == ERR_PTR && end_trigger == ';') {
5780 /* Discard cached input (rest of line) */
5781 int ch = inp->last_char;
5782 while (ch != EOF && ch != '\n') {
5783 //bb_error_msg("Discarded:'%c'", ch);
5788 /* This stream isn't empty */
5792 if (!pipe_list && empty)
5793 G.last_exitcode = 0;
5796 debug_print_tree(pipe_list, 0);
5797 debug_printf_exec("parse_and_run_stream: run_and_free_list\n");
5798 run_and_free_list(pipe_list);
5800 #if ENABLE_HUSH_FUNCTIONS
5801 if (G.flag_return_in_progress == 1)
5807 static void parse_and_run_string(const char *s)
5809 struct in_str input;
5810 setup_string_in_str(&input, s);
5811 parse_and_run_stream(&input, '\0');
5814 static void parse_and_run_file(FILE *f)
5816 struct in_str input;
5817 setup_file_in_str(&input, f);
5818 parse_and_run_stream(&input, ';');
5821 #if ENABLE_HUSH_TICK
5822 static FILE *generate_stream_from_string(const char *s, pid_t *pid_p)
5827 char **to_free = NULL;
5831 pid = BB_MMU ? xfork() : xvfork();
5832 if (pid == 0) { /* child */
5833 disable_restore_tty_pgrp_on_exit();
5834 /* Process substitution is not considered to be usual
5835 * 'command execution'.
5836 * SUSv3 says ctrl-Z should be ignored, ctrl-C should not.
5843 CLEAR_RANDOM_T(&G.random_gen); /* or else $RANDOM repeats in child */
5844 close(channel[0]); /* NB: close _first_, then move fd! */
5845 xmove_fd(channel[1], 1);
5846 /* Prevent it from trying to handle ctrl-z etc */
5847 IF_HUSH_JOB(G.run_list_level = 1;)
5848 /* Awful hack for `trap` or $(trap).
5850 * http://www.opengroup.org/onlinepubs/009695399/utilities/trap.html
5851 * contains an example where "trap" is executed in a subshell:
5853 * save_traps=$(trap)
5855 * eval "$save_traps"
5857 * Standard does not say that "trap" in subshell shall print
5858 * parent shell's traps. It only says that its output
5859 * must have suitable form, but then, in the above example
5860 * (which is not supposed to be normative), it implies that.
5862 * bash (and probably other shell) does implement it
5863 * (traps are reset to defaults, but "trap" still shows them),
5864 * but as a result, "trap" logic is hopelessly messed up:
5867 * trap -- 'echo Ho' SIGWINCH <--- we have a handler
5868 * # (trap) <--- trap is in subshell - no output (correct, traps are reset)
5869 * # true | trap <--- trap is in subshell - no output (ditto)
5870 * # echo `true | trap` <--- in subshell - output (but traps are reset!)
5871 * trap -- 'echo Ho' SIGWINCH
5872 * # echo `(trap)` <--- in subshell in subshell - output
5873 * trap -- 'echo Ho' SIGWINCH
5874 * # echo `true | (trap)` <--- in subshell in subshell in subshell - output!
5875 * trap -- 'echo Ho' SIGWINCH
5877 * The rules when to forget and when to not forget traps
5878 * get really complex and nonsensical.
5880 * Our solution: ONLY bare $(trap) or `trap` is special.
5882 s = skip_whitespace(s);
5883 if (strncmp(s, "trap", 4) == 0
5884 && skip_whitespace(s + 4)[0] == '\0'
5886 static const char *const argv[] = { NULL, NULL };
5887 builtin_trap((char**)argv);
5888 exit(0); /* not _exit() - we need to fflush */
5891 reset_traps_to_defaults();
5892 parse_and_run_string(s);
5893 _exit(G.last_exitcode);
5895 /* We re-execute after vfork on NOMMU. This makes this script safe:
5896 * yes "0123456789012345678901234567890" | dd bs=32 count=64k >BIG
5897 * huge=`cat BIG` # was blocking here forever
5900 re_execute_shell(&to_free,
5910 # if ENABLE_HUSH_FAST
5912 //bb_error_msg("[%d] fork in generate_stream_from_string:"
5913 // " G.count_SIGCHLD:%d G.handled_SIGCHLD:%d",
5914 // getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
5916 enable_restore_tty_pgrp_on_exit();
5921 close_on_exec_on(channel[0]);
5922 return xfdopen_for_read(channel[0]);
5925 /* Return code is exit status of the process that is run. */
5926 static int process_command_subs(o_string *dest, const char *s)
5929 struct in_str pipe_str;
5931 int status, ch, eol_cnt;
5933 fp = generate_stream_from_string(s, &pid);
5935 /* Now send results of command back into original context */
5936 setup_file_in_str(&pipe_str, fp);
5938 while ((ch = i_getch(&pipe_str)) != EOF) {
5944 o_addchr(dest, '\n');
5947 o_addQchr(dest, ch);
5950 debug_printf("done reading from `cmd` pipe, closing it\n");
5952 /* We need to extract exitcode. Test case
5953 * "true; echo `sleep 1; false` $?"
5955 safe_waitpid(pid, &status, 0);
5956 debug_printf("child exited. returning its exitcode:%d\n", WEXITSTATUS(status));
5957 return WEXITSTATUS(status);
5959 #endif /* ENABLE_HUSH_TICK */
5962 static void setup_heredoc(struct redir_struct *redir)
5964 struct fd_pair pair;
5967 /* the _body_ of heredoc (misleading field name) */
5968 const char *heredoc = redir->rd_filename;
5975 if (!(redir->rd_dup & HEREDOC_QUOTED)) {
5976 expanded = encode_then_expand_string(heredoc, /*process_bkslash:*/ 1, /*unbackslash:*/ 1);
5980 len = strlen(heredoc);
5982 close(redir->rd_fd); /* often saves dup2+close in xmove_fd */
5984 xmove_fd(pair.rd, redir->rd_fd);
5986 /* Try writing without forking. Newer kernels have
5987 * dynamically growing pipes. Must use non-blocking write! */
5990 written = write(pair.wr, heredoc, len);
6001 ndelay_off(pair.wr);
6003 /* Okay, pipe buffer was not big enough */
6004 /* Note: we must not create a stray child (bastard? :)
6005 * for the unsuspecting parent process. Child creates a grandchild
6006 * and exits before parent execs the process which consumes heredoc
6007 * (that exec happens after we return from this function) */
6014 disable_restore_tty_pgrp_on_exit();
6015 pid = BB_MMU ? xfork() : xvfork();
6019 close(redir->rd_fd); /* read side of the pipe */
6021 full_write(pair.wr, heredoc, len); /* may loop or block */
6024 /* Delegate blocking writes to another process */
6025 xmove_fd(pair.wr, STDOUT_FILENO);
6026 re_execute_shell(&to_free, heredoc, NULL, NULL, NULL);
6030 #if ENABLE_HUSH_FAST
6032 //bb_error_msg("[%d] fork in setup_heredoc: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
6034 enable_restore_tty_pgrp_on_exit();
6040 wait(NULL); /* wait till child has died */
6043 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
6044 * and stderr if they are redirected. */
6045 static int setup_redirects(struct command *prog, int squirrel[])
6048 struct redir_struct *redir;
6050 for (redir = prog->redirects; redir; redir = redir->next) {
6051 if (redir->rd_type == REDIRECT_HEREDOC2) {
6052 /* rd_fd<<HERE case */
6053 if (squirrel && redir->rd_fd < 3
6054 && squirrel[redir->rd_fd] < 0
6056 squirrel[redir->rd_fd] = dup(redir->rd_fd);
6058 /* for REDIRECT_HEREDOC2, rd_filename holds _contents_
6060 debug_printf_parse("set heredoc '%s'\n",
6061 redir->rd_filename);
6062 setup_heredoc(redir);
6066 if (redir->rd_dup == REDIRFD_TO_FILE) {
6067 /* rd_fd<*>file case (<*> is <,>,>>,<>) */
6069 if (redir->rd_filename == NULL) {
6070 /* Something went wrong in the parse.
6071 * Pretend it didn't happen */
6072 bb_error_msg("bug in redirect parse");
6075 mode = redir_table[redir->rd_type].mode;
6076 p = expand_string_to_string(redir->rd_filename, /*unbackslash:*/ 1);
6077 openfd = open_or_warn(p, mode);
6080 /* this could get lost if stderr has been redirected, but
6081 * bash and ash both lose it as well (though zsh doesn't!) */
6082 //what the above comment tries to say?
6086 /* rd_fd<*>rd_dup or rd_fd<*>- cases */
6087 openfd = redir->rd_dup;
6090 if (openfd != redir->rd_fd) {
6091 if (squirrel && redir->rd_fd < 3
6092 && squirrel[redir->rd_fd] < 0
6094 squirrel[redir->rd_fd] = dup(redir->rd_fd);
6096 if (openfd == REDIRFD_CLOSE) {
6097 /* "n>-" means "close me" */
6098 close(redir->rd_fd);
6100 xdup2(openfd, redir->rd_fd);
6101 if (redir->rd_dup == REDIRFD_TO_FILE)
6109 static void restore_redirects(int squirrel[])
6112 for (i = 0; i < 3; i++) {
6115 /* We simply die on error */
6121 static char *find_in_path(const char *arg)
6124 const char *PATH = get_local_var_value("PATH");
6130 const char *end = strchrnul(PATH, ':');
6131 int sz = end - PATH; /* must be int! */
6135 ret = xasprintf("%.*s/%s", sz, PATH, arg);
6137 /* We have xxx::yyyy in $PATH,
6138 * it means "use current dir" */
6141 if (access(ret, F_OK) == 0)
6154 static const struct built_in_command *find_builtin_helper(const char *name,
6155 const struct built_in_command *x,
6156 const struct built_in_command *end)
6159 if (strcmp(name, x->b_cmd) != 0) {
6163 debug_printf_exec("found builtin '%s'\n", name);
6168 static const struct built_in_command *find_builtin1(const char *name)
6170 return find_builtin_helper(name, bltins1, &bltins1[ARRAY_SIZE(bltins1)]);
6172 static const struct built_in_command *find_builtin(const char *name)
6174 const struct built_in_command *x = find_builtin1(name);
6177 return find_builtin_helper(name, bltins2, &bltins2[ARRAY_SIZE(bltins2)]);
6180 #if ENABLE_HUSH_FUNCTIONS
6181 static struct function **find_function_slot(const char *name)
6183 struct function **funcpp = &G.top_func;
6185 if (strcmp(name, (*funcpp)->name) == 0) {
6188 funcpp = &(*funcpp)->next;
6193 static const struct function *find_function(const char *name)
6195 const struct function *funcp = *find_function_slot(name);
6197 debug_printf_exec("found function '%s'\n", name);
6201 /* Note: takes ownership on name ptr */
6202 static struct function *new_function(char *name)
6204 struct function **funcpp = find_function_slot(name);
6205 struct function *funcp = *funcpp;
6207 if (funcp != NULL) {
6208 struct command *cmd = funcp->parent_cmd;
6209 debug_printf_exec("func %p parent_cmd %p\n", funcp, cmd);
6211 debug_printf_exec("freeing & replacing function '%s'\n", funcp->name);
6213 /* Note: if !funcp->body, do not free body_as_string!
6214 * This is a special case of "-F name body" function:
6215 * body_as_string was not malloced! */
6217 free_pipe_list(funcp->body);
6219 free(funcp->body_as_string);
6223 debug_printf_exec("reinserting in tree & replacing function '%s'\n", funcp->name);
6224 cmd->argv[0] = funcp->name;
6225 cmd->group = funcp->body;
6227 cmd->group_as_string = funcp->body_as_string;
6231 debug_printf_exec("remembering new function '%s'\n", name);
6232 funcp = *funcpp = xzalloc(sizeof(*funcp));
6233 /*funcp->next = NULL;*/
6240 static void unset_func(const char *name)
6242 struct function **funcpp = find_function_slot(name);
6243 struct function *funcp = *funcpp;
6245 if (funcp != NULL) {
6246 debug_printf_exec("freeing function '%s'\n", funcp->name);
6247 *funcpp = funcp->next;
6248 /* funcp is unlinked now, deleting it.
6249 * Note: if !funcp->body, the function was created by
6250 * "-F name body", do not free ->body_as_string
6251 * and ->name as they were not malloced. */
6253 free_pipe_list(funcp->body);
6256 free(funcp->body_as_string);
6264 #define exec_function(to_free, funcp, argv) \
6265 exec_function(funcp, argv)
6267 static void exec_function(char ***to_free,
6268 const struct function *funcp,
6269 char **argv) NORETURN;
6270 static void exec_function(char ***to_free,
6271 const struct function *funcp,
6277 argv[0] = G.global_argv[0];
6278 G.global_argv = argv;
6282 /* On MMU, funcp->body is always non-NULL */
6283 n = run_list(funcp->body);
6287 re_execute_shell(to_free,
6288 funcp->body_as_string,
6295 static int run_function(const struct function *funcp, char **argv)
6301 save_and_replace_G_args(&sv, argv);
6303 /* "we are in function, ok to use return" */
6304 sv_flg = G.flag_return_in_progress;
6305 G.flag_return_in_progress = -1;
6306 # if ENABLE_HUSH_LOCAL
6307 G.func_nest_level++;
6310 /* On MMU, funcp->body is always non-NULL */
6313 /* Function defined by -F */
6314 parse_and_run_string(funcp->body_as_string);
6315 rc = G.last_exitcode;
6319 rc = run_list(funcp->body);
6322 # if ENABLE_HUSH_LOCAL
6324 struct variable *var;
6325 struct variable **var_pp;
6327 var_pp = &G.top_var;
6328 while ((var = *var_pp) != NULL) {
6329 if (var->func_nest_level < G.func_nest_level) {
6330 var_pp = &var->next;
6334 if (var->flg_export)
6335 bb_unsetenv(var->varstr);
6336 /* Remove from global list */
6337 *var_pp = var->next;
6343 G.func_nest_level--;
6346 G.flag_return_in_progress = sv_flg;
6348 restore_G_args(&sv, argv);
6352 #endif /* ENABLE_HUSH_FUNCTIONS */
6356 #define exec_builtin(to_free, x, argv) \
6357 exec_builtin(x, argv)
6359 #define exec_builtin(to_free, x, argv) \
6360 exec_builtin(to_free, argv)
6362 static void exec_builtin(char ***to_free,
6363 const struct built_in_command *x,
6364 char **argv) NORETURN;
6365 static void exec_builtin(char ***to_free,
6366 const struct built_in_command *x,
6372 rcode = x->b_function(argv);
6377 /* On NOMMU, we must never block!
6378 * Example: { sleep 99 | read line; } & echo Ok
6380 re_execute_shell(to_free,
6389 static void execvp_or_die(char **argv) NORETURN;
6390 static void execvp_or_die(char **argv)
6392 debug_printf_exec("execing '%s'\n", argv[0]);
6393 /* Don't propagate SIG_IGN to the child */
6394 if (SPECIAL_JOBSTOP_SIGS != 0)
6395 switch_off_special_sigs(G.special_sig_mask & SPECIAL_JOBSTOP_SIGS);
6396 execvp(argv[0], argv);
6397 bb_perror_msg("can't execute '%s'", argv[0]);
6398 _exit(127); /* bash compat */
6401 #if ENABLE_HUSH_MODE_X
6402 static void dump_cmd_in_x_mode(char **argv)
6404 if (G_x_mode && argv) {
6405 /* We want to output the line in one write op */
6413 len += strlen(argv[n++]) + 1;
6419 p += sprintf(p, " %s", argv[n++]);
6427 # define dump_cmd_in_x_mode(argv) ((void)0)
6431 #define pseudo_exec_argv(nommu_save, argv, assignment_cnt, argv_expanded) \
6432 pseudo_exec_argv(argv, assignment_cnt, argv_expanded)
6433 #define pseudo_exec(nommu_save, command, argv_expanded) \
6434 pseudo_exec(command, argv_expanded)
6437 /* Called after [v]fork() in run_pipe, or from builtin_exec.
6439 * Don't exit() here. If you don't exec, use _exit instead.
6440 * The at_exit handlers apparently confuse the calling process,
6441 * in particular stdin handling. Not sure why? -- because of vfork! (vda) */
6442 static void pseudo_exec_argv(nommu_save_t *nommu_save,
6443 char **argv, int assignment_cnt,
6444 char **argv_expanded) NORETURN;
6445 static NOINLINE void pseudo_exec_argv(nommu_save_t *nommu_save,
6446 char **argv, int assignment_cnt,
6447 char **argv_expanded)
6451 new_env = expand_assignments(argv, assignment_cnt);
6452 dump_cmd_in_x_mode(new_env);
6454 if (!argv[assignment_cnt]) {
6455 /* Case when we are here: ... | var=val | ...
6456 * (note that we do not exit early, i.e., do not optimize out
6457 * expand_assignments(): think about ... | var=`sleep 1` | ...
6459 free_strings(new_env);
6460 _exit(EXIT_SUCCESS);
6464 set_vars_and_save_old(new_env);
6465 free(new_env); /* optional */
6466 /* we can also destroy set_vars_and_save_old's return value,
6469 nommu_save->new_env = new_env;
6470 nommu_save->old_vars = set_vars_and_save_old(new_env);
6473 if (argv_expanded) {
6474 argv = argv_expanded;
6476 argv = expand_strvec_to_strvec(argv + assignment_cnt);
6478 nommu_save->argv = argv;
6481 dump_cmd_in_x_mode(argv);
6483 #if ENABLE_FEATURE_SH_STANDALONE || BB_MMU
6484 if (strchr(argv[0], '/') != NULL)
6488 /* Check if the command matches any of the builtins.
6489 * Depending on context, this might be redundant. But it's
6490 * easier to waste a few CPU cycles than it is to figure out
6491 * if this is one of those cases.
6494 /* On NOMMU, it is more expensive to re-execute shell
6495 * just in order to run echo or test builtin.
6496 * It's better to skip it here and run corresponding
6497 * non-builtin later. */
6498 const struct built_in_command *x;
6499 x = BB_MMU ? find_builtin(argv[0]) : find_builtin1(argv[0]);
6501 exec_builtin(&nommu_save->argv_from_re_execing, x, argv);
6504 #if ENABLE_HUSH_FUNCTIONS
6505 /* Check if the command matches any functions */
6507 const struct function *funcp = find_function(argv[0]);
6509 exec_function(&nommu_save->argv_from_re_execing, funcp, argv);
6514 #if ENABLE_FEATURE_SH_STANDALONE
6515 /* Check if the command matches any busybox applets */
6517 int a = find_applet_by_name(argv[0]);
6519 # if BB_MMU /* see above why on NOMMU it is not allowed */
6520 if (APPLET_IS_NOEXEC(a)) {
6521 debug_printf_exec("running applet '%s'\n", argv[0]);
6522 run_applet_no_and_exit(a, argv);
6525 /* Re-exec ourselves */
6526 debug_printf_exec("re-execing applet '%s'\n", argv[0]);
6527 /* Don't propagate SIG_IGN to the child */
6528 if (SPECIAL_JOBSTOP_SIGS != 0)
6529 switch_off_special_sigs(G.special_sig_mask & SPECIAL_JOBSTOP_SIGS);
6530 execv(bb_busybox_exec_path, argv);
6531 /* If they called chroot or otherwise made the binary no longer
6532 * executable, fall through */
6537 #if ENABLE_FEATURE_SH_STANDALONE || BB_MMU
6540 execvp_or_die(argv);
6543 /* Called after [v]fork() in run_pipe
6545 static void pseudo_exec(nommu_save_t *nommu_save,
6546 struct command *command,
6547 char **argv_expanded) NORETURN;
6548 static void pseudo_exec(nommu_save_t *nommu_save,
6549 struct command *command,
6550 char **argv_expanded)
6552 if (command->argv) {
6553 pseudo_exec_argv(nommu_save, command->argv,
6554 command->assignment_cnt, argv_expanded);
6557 if (command->group) {
6558 /* Cases when we are here:
6561 * ... | ( list ) | ...
6562 * ... | { list } | ...
6566 debug_printf_exec("pseudo_exec: run_list\n");
6567 reset_traps_to_defaults();
6568 rcode = run_list(command->group);
6569 /* OK to leak memory by not calling free_pipe_list,
6570 * since this process is about to exit */
6573 re_execute_shell(&nommu_save->argv_from_re_execing,
6574 command->group_as_string,
6581 /* Case when we are here: ... | >file */
6582 debug_printf_exec("pseudo_exec'ed null command\n");
6583 _exit(EXIT_SUCCESS);
6587 static const char *get_cmdtext(struct pipe *pi)
6593 /* This is subtle. ->cmdtext is created only on first backgrounding.
6594 * (Think "cat, <ctrl-z>, fg, <ctrl-z>, fg, <ctrl-z>...." here...)
6595 * On subsequent bg argv is trashed, but we won't use it */
6598 argv = pi->cmds[0].argv;
6599 if (!argv || !argv[0]) {
6600 pi->cmdtext = xzalloc(1);
6606 len += strlen(*argv) + 1;
6610 argv = pi->cmds[0].argv;
6612 len = strlen(*argv);
6613 memcpy(p, *argv, len);
6621 static void insert_bg_job(struct pipe *pi)
6623 struct pipe *job, **jobp;
6626 /* Linear search for the ID of the job to use */
6628 for (job = G.job_list; job; job = job->next)
6629 if (job->jobid >= pi->jobid)
6630 pi->jobid = job->jobid + 1;
6632 /* Add job to the list of running jobs */
6634 while ((job = *jobp) != NULL)
6636 job = *jobp = xmalloc(sizeof(*job));
6638 *job = *pi; /* physical copy */
6640 job->cmds = xzalloc(sizeof(pi->cmds[0]) * pi->num_cmds);
6641 /* Cannot copy entire pi->cmds[] vector! This causes double frees */
6642 for (i = 0; i < pi->num_cmds; i++) {
6643 job->cmds[i].pid = pi->cmds[i].pid;
6644 /* all other fields are not used and stay zero */
6646 job->cmdtext = xstrdup(get_cmdtext(pi));
6648 if (G_interactive_fd)
6649 printf("[%d] %d %s\n", job->jobid, job->cmds[0].pid, job->cmdtext);
6650 G.last_jobid = job->jobid;
6653 static void remove_bg_job(struct pipe *pi)
6655 struct pipe *prev_pipe;
6657 if (pi == G.job_list) {
6658 G.job_list = pi->next;
6660 prev_pipe = G.job_list;
6661 while (prev_pipe->next != pi)
6662 prev_pipe = prev_pipe->next;
6663 prev_pipe->next = pi->next;
6666 G.last_jobid = G.job_list->jobid;
6671 /* Remove a backgrounded job */
6672 static void delete_finished_bg_job(struct pipe *pi)
6679 /* Check to see if any processes have exited -- if they
6680 * have, figure out why and see if a job has completed */
6681 static int checkjobs(struct pipe *fg_pipe)
6691 debug_printf_jobs("checkjobs %p\n", fg_pipe);
6693 attributes = WUNTRACED;
6694 if (fg_pipe == NULL)
6695 attributes |= WNOHANG;
6698 #if ENABLE_HUSH_FAST
6699 if (G.handled_SIGCHLD == G.count_SIGCHLD) {
6700 //bb_error_msg("[%d] checkjobs: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d children?:%d fg_pipe:%p",
6701 //getpid(), G.count_SIGCHLD, G.handled_SIGCHLD, G.we_have_children, fg_pipe);
6702 /* There was neither fork nor SIGCHLD since last waitpid */
6703 /* Avoid doing waitpid syscall if possible */
6704 if (!G.we_have_children) {
6708 if (fg_pipe == NULL) { /* is WNOHANG set? */
6709 /* We have children, but they did not exit
6710 * or stop yet (we saw no SIGCHLD) */
6713 /* else: !WNOHANG, waitpid will block, can't short-circuit */
6717 /* Do we do this right?
6718 * bash-3.00# sleep 20 | false
6720 * [3]+ Stopped sleep 20 | false
6721 * bash-3.00# echo $?
6722 * 1 <========== bg pipe is not fully done, but exitcode is already known!
6723 * [hush 1.14.0: yes we do it right]
6730 #if ENABLE_HUSH_FAST
6731 i = G.count_SIGCHLD;
6733 childpid = waitpid(-1, &status, attributes);
6734 if (childpid <= 0) {
6735 if (childpid && errno != ECHILD)
6736 bb_perror_msg("waitpid");
6737 #if ENABLE_HUSH_FAST
6738 else { /* Until next SIGCHLD, waitpid's are useless */
6739 G.we_have_children = (childpid == 0);
6740 G.handled_SIGCHLD = i;
6741 //bb_error_msg("[%d] checkjobs: waitpid returned <= 0, G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
6746 dead = WIFEXITED(status) || WIFSIGNALED(status);
6749 if (WIFSTOPPED(status))
6750 debug_printf_jobs("pid %d stopped by sig %d (exitcode %d)\n",
6751 childpid, WSTOPSIG(status), WEXITSTATUS(status));
6752 if (WIFSIGNALED(status))
6753 debug_printf_jobs("pid %d killed by sig %d (exitcode %d)\n",
6754 childpid, WTERMSIG(status), WEXITSTATUS(status));
6755 if (WIFEXITED(status))
6756 debug_printf_jobs("pid %d exited, exitcode %d\n",
6757 childpid, WEXITSTATUS(status));
6759 /* Were we asked to wait for fg pipe? */
6761 i = fg_pipe->num_cmds;
6763 debug_printf_jobs("check pid %d\n", fg_pipe->cmds[i].pid);
6764 if (fg_pipe->cmds[i].pid != childpid)
6768 fg_pipe->cmds[i].pid = 0;
6769 fg_pipe->alive_cmds--;
6770 ex = WEXITSTATUS(status);
6771 /* bash prints killer signal's name for *last*
6772 * process in pipe (prints just newline for SIGINT/SIGPIPE).
6773 * Mimic this. Example: "sleep 5" + (^\ or kill -QUIT)
6775 if (WIFSIGNALED(status)) {
6776 int sig = WTERMSIG(status);
6777 if (i == fg_pipe->num_cmds-1)
6778 /* TODO: use strsignal() instead for bash compat? but that's bloat... */
6779 printf("%s\n", sig == SIGINT || sig == SIGPIPE ? "" : get_signame(sig));
6780 /* TODO: if (WCOREDUMP(status)) + " (core dumped)"; */
6781 /* TODO: MIPS has 128 sigs (1..128), what if sig==128 here?
6782 * Maybe we need to use sig | 128? */
6785 fg_pipe->cmds[i].cmd_exitcode = ex;
6787 fg_pipe->stopped_cmds++;
6789 debug_printf_jobs("fg_pipe: alive_cmds %d stopped_cmds %d\n",
6790 fg_pipe->alive_cmds, fg_pipe->stopped_cmds);
6791 if (fg_pipe->alive_cmds == fg_pipe->stopped_cmds) {
6792 /* All processes in fg pipe have exited or stopped */
6793 i = fg_pipe->num_cmds;
6795 rcode = fg_pipe->cmds[i].cmd_exitcode;
6796 /* usually last process gives overall exitstatus,
6797 * but with "set -o pipefail", last *failed* process does */
6798 if (G.o_opt[OPT_O_PIPEFAIL] == 0 || rcode != 0)
6801 IF_HAS_KEYWORDS(if (fg_pipe->pi_inverted) rcode = !rcode;)
6802 /* Note: *non-interactive* bash does not continue if all processes in fg pipe
6803 * are stopped. Testcase: "cat | cat" in a script (not on command line!)
6804 * and "killall -STOP cat" */
6805 if (G_interactive_fd) {
6807 if (fg_pipe->alive_cmds != 0)
6808 insert_bg_job(fg_pipe);
6812 if (fg_pipe->alive_cmds == 0)
6815 /* There are still running processes in the fg pipe */
6816 goto wait_more; /* do waitpid again */
6818 /* it wasnt fg_pipe, look for process in bg pipes */
6822 /* We asked to wait for bg or orphaned children */
6823 /* No need to remember exitcode in this case */
6824 for (pi = G.job_list; pi; pi = pi->next) {
6825 for (i = 0; i < pi->num_cmds; i++) {
6826 if (pi->cmds[i].pid == childpid)
6827 goto found_pi_and_prognum;
6830 /* Happens when shell is used as init process (init=/bin/sh) */
6831 debug_printf("checkjobs: pid %d was not in our list!\n", childpid);
6832 continue; /* do waitpid again */
6834 found_pi_and_prognum:
6837 pi->cmds[i].pid = 0;
6839 if (!pi->alive_cmds) {
6840 if (G_interactive_fd)
6841 printf(JOB_STATUS_FORMAT, pi->jobid,
6842 "Done", pi->cmdtext);
6843 delete_finished_bg_job(pi);
6850 } /* while (waitpid succeeds)... */
6856 static int checkjobs_and_fg_shell(struct pipe *fg_pipe)
6859 int rcode = checkjobs(fg_pipe);
6860 if (G_saved_tty_pgrp) {
6861 /* Job finished, move the shell to the foreground */
6862 p = getpgrp(); /* our process group id */
6863 debug_printf_jobs("fg'ing ourself: getpgrp()=%d\n", (int)p);
6864 tcsetpgrp(G_interactive_fd, p);
6870 /* Start all the jobs, but don't wait for anything to finish.
6873 * Return code is normally -1, when the caller has to wait for children
6874 * to finish to determine the exit status of the pipe. If the pipe
6875 * is a simple builtin command, however, the action is done by the
6876 * time run_pipe returns, and the exit code is provided as the
6879 * Returns -1 only if started some children. IOW: we have to
6880 * mask out retvals of builtins etc with 0xff!
6882 * The only case when we do not need to [v]fork is when the pipe
6883 * is single, non-backgrounded, non-subshell command. Examples:
6884 * cmd ; ... { list } ; ...
6885 * cmd && ... { list } && ...
6886 * cmd || ... { list } || ...
6887 * If it is, then we can run cmd as a builtin, NOFORK,
6888 * or (if SH_STANDALONE) an applet, and we can run the { list }
6889 * with run_list. If it isn't one of these, we fork and exec cmd.
6891 * Cases when we must fork:
6892 * non-single: cmd | cmd
6893 * backgrounded: cmd & { list } &
6894 * subshell: ( list ) [&]
6896 #if !ENABLE_HUSH_MODE_X
6897 #define redirect_and_varexp_helper(new_env_p, old_vars_p, command, squirrel, argv_expanded) \
6898 redirect_and_varexp_helper(new_env_p, old_vars_p, command, squirrel)
6900 static int redirect_and_varexp_helper(char ***new_env_p,
6901 struct variable **old_vars_p,
6902 struct command *command,
6904 char **argv_expanded)
6906 /* setup_redirects acts on file descriptors, not FILEs.
6907 * This is perfect for work that comes after exec().
6908 * Is it really safe for inline use? Experimentally,
6909 * things seem to work. */
6910 int rcode = setup_redirects(command, squirrel);
6912 char **new_env = expand_assignments(command->argv, command->assignment_cnt);
6913 *new_env_p = new_env;
6914 dump_cmd_in_x_mode(new_env);
6915 dump_cmd_in_x_mode(argv_expanded);
6917 *old_vars_p = set_vars_and_save_old(new_env);
6921 static NOINLINE int run_pipe(struct pipe *pi)
6923 static const char *const null_ptr = NULL;
6927 struct command *command;
6928 char **argv_expanded;
6930 /* it is not always needed, but we aim to smaller code */
6931 int squirrel[] = { -1, -1, -1 };
6934 debug_printf_exec("run_pipe start: members:%d\n", pi->num_cmds);
6937 /* Testcase: set -- q w e; (IFS='' echo "$*"; IFS=''; echo "$*"); echo "$*"
6938 * Result should be 3 lines: q w e, qwe, q w e
6940 G.ifs = get_local_var_value("IFS");
6944 IF_HUSH_JOB(pi->pgrp = -1;)
6945 pi->stopped_cmds = 0;
6946 command = &pi->cmds[0];
6947 argv_expanded = NULL;
6949 if (pi->num_cmds != 1
6950 || pi->followup == PIPE_BG
6951 || command->cmd_type == CMD_SUBSHELL
6958 debug_printf_exec(": group:%p argv:'%s'\n",
6959 command->group, command->argv ? command->argv[0] : "NONE");
6961 if (command->group) {
6962 #if ENABLE_HUSH_FUNCTIONS
6963 if (command->cmd_type == CMD_FUNCDEF) {
6964 /* "executing" func () { list } */
6965 struct function *funcp;
6967 funcp = new_function(command->argv[0]);
6968 /* funcp->name is already set to argv[0] */
6969 funcp->body = command->group;
6971 funcp->body_as_string = command->group_as_string;
6972 command->group_as_string = NULL;
6974 command->group = NULL;
6975 command->argv[0] = NULL;
6976 debug_printf_exec("cmd %p has child func at %p\n", command, funcp);
6977 funcp->parent_cmd = command;
6978 command->child_func = funcp;
6980 debug_printf_exec("run_pipe: return EXIT_SUCCESS\n");
6982 return EXIT_SUCCESS;
6986 debug_printf("non-subshell group\n");
6987 rcode = 1; /* exitcode if redir failed */
6988 if (setup_redirects(command, squirrel) == 0) {
6989 debug_printf_exec(": run_list\n");
6990 rcode = run_list(command->group) & 0xff;
6992 restore_redirects(squirrel);
6993 IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;)
6995 debug_printf_exec("run_pipe: return %d\n", rcode);
6999 argv = command->argv ? command->argv : (char **) &null_ptr;
7001 const struct built_in_command *x;
7002 #if ENABLE_HUSH_FUNCTIONS
7003 const struct function *funcp;
7007 char **new_env = NULL;
7008 struct variable *old_vars = NULL;
7010 if (argv[command->assignment_cnt] == NULL) {
7011 /* Assignments, but no command */
7012 /* Ensure redirects take effect (that is, create files).
7013 * Try "a=t >file" */
7014 #if 0 /* A few cases in testsuite fail with this code. FIXME */
7015 rcode = redirect_and_varexp_helper(&new_env, /*old_vars:*/ NULL, command, squirrel, /*argv_expanded:*/ NULL);
7016 /* Set shell variables */
7020 set_local_var(*argv, /*exp:*/ 0, /*lvl:*/ 0, /*ro:*/ 0);
7021 /* Do we need to flag set_local_var() errors?
7022 * "assignment to readonly var" and "putenv error"
7027 /* Redirect error sets $? to 1. Otherwise,
7028 * if evaluating assignment value set $?, retain it.
7029 * Try "false; q=`exit 2`; echo $?" - should print 2: */
7031 rcode = G.last_exitcode;
7032 /* Exit, _skipping_ variable restoring code: */
7033 goto clean_up_and_ret0;
7035 #else /* Older, bigger, but more correct code */
7037 rcode = setup_redirects(command, squirrel);
7038 restore_redirects(squirrel);
7039 /* Set shell variables */
7041 bb_putchar_stderr('+');
7043 char *p = expand_string_to_string(*argv, /*unbackslash:*/ 1);
7045 fprintf(stderr, " %s", p);
7046 debug_printf_exec("set shell var:'%s'->'%s'\n",
7048 set_local_var(p, /*exp:*/ 0, /*lvl:*/ 0, /*ro:*/ 0);
7049 /* Do we need to flag set_local_var() errors?
7050 * "assignment to readonly var" and "putenv error"
7055 bb_putchar_stderr('\n');
7056 /* Redirect error sets $? to 1. Otherwise,
7057 * if evaluating assignment value set $?, retain it.
7058 * Try "false; q=`exit 2`; echo $?" - should print 2: */
7060 rcode = G.last_exitcode;
7061 IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;)
7063 debug_printf_exec("run_pipe: return %d\n", rcode);
7068 /* Expand the rest into (possibly) many strings each */
7069 #if ENABLE_HUSH_BASH_COMPAT
7070 if (command->cmd_type == CMD_SINGLEWORD_NOGLOB) {
7071 argv_expanded = expand_strvec_to_strvec_singleword_noglob(argv + command->assignment_cnt);
7075 argv_expanded = expand_strvec_to_strvec(argv + command->assignment_cnt);
7078 /* if someone gives us an empty string: `cmd with empty output` */
7079 if (!argv_expanded[0]) {
7080 free(argv_expanded);
7082 return G.last_exitcode;
7085 x = find_builtin(argv_expanded[0]);
7086 #if ENABLE_HUSH_FUNCTIONS
7089 funcp = find_function(argv_expanded[0]);
7093 if (x->b_function == builtin_exec && argv_expanded[1] == NULL) {
7094 debug_printf("exec with redirects only\n");
7095 rcode = setup_redirects(command, NULL);
7096 goto clean_up_and_ret1;
7099 rcode = redirect_and_varexp_helper(&new_env, &old_vars, command, squirrel, argv_expanded);
7102 debug_printf_exec(": builtin '%s' '%s'...\n",
7103 x->b_cmd, argv_expanded[1]);
7105 rcode = x->b_function(argv_expanded) & 0xff;
7108 #if ENABLE_HUSH_FUNCTIONS
7110 # if ENABLE_HUSH_LOCAL
7111 struct variable **sv;
7112 sv = G.shadowed_vars_pp;
7113 G.shadowed_vars_pp = &old_vars;
7115 debug_printf_exec(": function '%s' '%s'...\n",
7116 funcp->name, argv_expanded[1]);
7117 rcode = run_function(funcp, argv_expanded) & 0xff;
7118 # if ENABLE_HUSH_LOCAL
7119 G.shadowed_vars_pp = sv;
7125 unset_vars(new_env);
7127 /* clean_up_and_ret0: */
7128 restore_redirects(squirrel);
7130 free(argv_expanded);
7131 IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;)
7133 debug_printf_exec("run_pipe return %d\n", rcode);
7137 if (ENABLE_FEATURE_SH_NOFORK) {
7138 int n = find_applet_by_name(argv_expanded[0]);
7139 if (n >= 0 && APPLET_IS_NOFORK(n)) {
7140 rcode = redirect_and_varexp_helper(&new_env, &old_vars, command, squirrel, argv_expanded);
7142 debug_printf_exec(": run_nofork_applet '%s' '%s'...\n",
7143 argv_expanded[0], argv_expanded[1]);
7144 rcode = run_nofork_applet(n, argv_expanded);
7146 goto clean_up_and_ret;
7149 /* It is neither builtin nor applet. We must fork. */
7153 /* NB: argv_expanded may already be created, and that
7154 * might include `cmd` runs! Do not rerun it! We *must*
7155 * use argv_expanded if it's non-NULL */
7157 /* Going to fork a child per each pipe member */
7162 while (cmd_no < pi->num_cmds) {
7163 struct fd_pair pipefds;
7165 volatile nommu_save_t nommu_save;
7166 nommu_save.new_env = NULL;
7167 nommu_save.old_vars = NULL;
7168 nommu_save.argv = NULL;
7169 nommu_save.argv_from_re_execing = NULL;
7171 command = &pi->cmds[cmd_no];
7173 if (command->argv) {
7174 debug_printf_exec(": pipe member '%s' '%s'...\n",
7175 command->argv[0], command->argv[1]);
7177 debug_printf_exec(": pipe member with no argv\n");
7180 /* pipes are inserted between pairs of commands */
7183 if (cmd_no < pi->num_cmds)
7184 xpiped_pair(pipefds);
7186 command->pid = BB_MMU ? fork() : vfork();
7187 if (!command->pid) { /* child */
7189 disable_restore_tty_pgrp_on_exit();
7190 CLEAR_RANDOM_T(&G.random_gen); /* or else $RANDOM repeats in child */
7192 /* Every child adds itself to new process group
7193 * with pgid == pid_of_first_child_in_pipe */
7194 if (G.run_list_level == 1 && G_interactive_fd) {
7197 if (pgrp < 0) /* true for 1st process only */
7199 if (setpgid(0, pgrp) == 0
7200 && pi->followup != PIPE_BG
7201 && G_saved_tty_pgrp /* we have ctty */
7203 /* We do it in *every* child, not just first,
7205 tcsetpgrp(G_interactive_fd, pgrp);
7209 if (pi->alive_cmds == 0 && pi->followup == PIPE_BG) {
7210 /* 1st cmd in backgrounded pipe
7211 * should have its stdin /dev/null'ed */
7213 if (open(bb_dev_null, O_RDONLY))
7214 xopen("/", O_RDONLY);
7216 xmove_fd(next_infd, 0);
7218 xmove_fd(pipefds.wr, 1);
7221 /* Like bash, explicit redirects override pipes,
7222 * and the pipe fd is available for dup'ing. */
7223 if (setup_redirects(command, NULL))
7226 /* Stores to nommu_save list of env vars putenv'ed
7227 * (NOMMU, on MMU we don't need that) */
7228 /* cast away volatility... */
7229 pseudo_exec((nommu_save_t*) &nommu_save, command, argv_expanded);
7230 /* pseudo_exec() does not return */
7233 /* parent or error */
7234 #if ENABLE_HUSH_FAST
7236 //bb_error_msg("[%d] fork in run_pipe: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
7238 enable_restore_tty_pgrp_on_exit();
7240 /* Clean up after vforked child */
7241 free(nommu_save.argv);
7242 free(nommu_save.argv_from_re_execing);
7243 unset_vars(nommu_save.new_env);
7244 add_vars(nommu_save.old_vars);
7246 free(argv_expanded);
7247 argv_expanded = NULL;
7248 if (command->pid < 0) { /* [v]fork failed */
7249 /* Clearly indicate, was it fork or vfork */
7250 bb_perror_msg(BB_MMU ? "vfork"+1 : "vfork");
7254 /* Second and next children need to know pid of first one */
7256 pi->pgrp = command->pid;
7262 if (cmd_no < pi->num_cmds)
7264 /* Pass read (output) pipe end to next iteration */
7265 next_infd = pipefds.rd;
7268 if (!pi->alive_cmds) {
7270 debug_printf_exec("run_pipe return 1 (all forks failed, no children)\n");
7275 debug_printf_exec("run_pipe return -1 (%u children started)\n", pi->alive_cmds);
7279 /* NB: called by pseudo_exec, and therefore must not modify any
7280 * global data until exec/_exit (we can be a child after vfork!) */
7281 static int run_list(struct pipe *pi)
7283 #if ENABLE_HUSH_CASE
7284 char *case_word = NULL;
7286 #if ENABLE_HUSH_LOOPS
7287 struct pipe *loop_top = NULL;
7288 char **for_lcur = NULL;
7289 char **for_list = NULL;
7291 smallint last_followup;
7293 #if ENABLE_HUSH_IF || ENABLE_HUSH_CASE
7294 smalluint cond_code = 0;
7296 enum { cond_code = 0 };
7299 smallint rword; /* RES_foo */
7300 smallint last_rword; /* ditto */
7303 debug_printf_exec("run_list start lvl %d\n", G.run_list_level);
7306 #if ENABLE_HUSH_LOOPS
7307 /* Check syntax for "for" */
7310 for (cpipe = pi; cpipe; cpipe = cpipe->next) {
7311 if (cpipe->res_word != RES_FOR && cpipe->res_word != RES_IN)
7313 /* current word is FOR or IN (BOLD in comments below) */
7314 if (cpipe->next == NULL) {
7315 syntax_error("malformed for");
7317 debug_printf_exec("run_list lvl %d return 1\n", G.run_list_level);
7320 /* "FOR v; do ..." and "for v IN a b; do..." are ok */
7321 if (cpipe->next->res_word == RES_DO)
7323 /* next word is not "do". It must be "in" then ("FOR v in ...") */
7324 if (cpipe->res_word == RES_IN /* "for v IN a b; not_do..."? */
7325 || cpipe->next->res_word != RES_IN /* FOR v not_do_and_not_in..."? */
7327 syntax_error("malformed for");
7329 debug_printf_exec("run_list lvl %d return 1\n", G.run_list_level);
7336 /* Past this point, all code paths should jump to ret: label
7337 * in order to return, no direct "return" statements please.
7338 * This helps to ensure that no memory is leaked. */
7346 last_rword = RES_XXXX;
7348 last_followup = PIPE_SEQ;
7349 rcode = G.last_exitcode;
7351 /* Go through list of pipes, (maybe) executing them. */
7352 for (; pi; pi = IF_HUSH_LOOPS(rword == RES_DONE ? loop_top : ) pi->next) {
7356 IF_HAS_KEYWORDS(rword = pi->res_word;)
7357 debug_printf_exec(": rword=%d cond_code=%d last_rword=%d\n",
7358 rword, cond_code, last_rword);
7359 #if ENABLE_HUSH_LOOPS
7360 if ((rword == RES_WHILE || rword == RES_UNTIL || rword == RES_FOR)
7361 && loop_top == NULL /* avoid bumping G.depth_of_loop twice */
7363 /* start of a loop: remember where loop starts */
7368 /* Still in the same "if...", "then..." or "do..." branch? */
7369 if (IF_HAS_KEYWORDS(rword == last_rword &&) 1) {
7370 if ((rcode == 0 && last_followup == PIPE_OR)
7371 || (rcode != 0 && last_followup == PIPE_AND)
7373 /* It is "<true> || CMD" or "<false> && CMD"
7374 * and we should not execute CMD */
7375 debug_printf_exec("skipped cmd because of || or &&\n");
7376 last_followup = pi->followup;
7377 goto dont_check_jobs_but_continue;
7380 last_followup = pi->followup;
7381 IF_HAS_KEYWORDS(last_rword = rword;)
7384 if (rword == RES_THEN) {
7385 /* if false; then ... fi has exitcode 0! */
7386 G.last_exitcode = rcode = EXIT_SUCCESS;
7387 /* "if <false> THEN cmd": skip cmd */
7391 if (rword == RES_ELSE || rword == RES_ELIF) {
7392 /* "if <true> then ... ELSE/ELIF cmd":
7393 * skip cmd and all following ones */
7398 #if ENABLE_HUSH_LOOPS
7399 if (rword == RES_FOR) { /* && pi->num_cmds - always == 1 */
7401 /* first loop through for */
7403 static const char encoded_dollar_at[] ALIGN1 = {
7404 SPECIAL_VAR_SYMBOL, '@' | 0x80, SPECIAL_VAR_SYMBOL, '\0'
7405 }; /* encoded representation of "$@" */
7406 static const char *const encoded_dollar_at_argv[] = {
7407 encoded_dollar_at, NULL
7408 }; /* argv list with one element: "$@" */
7411 vals = (char**)encoded_dollar_at_argv;
7412 if (pi->next->res_word == RES_IN) {
7413 /* if no variable values after "in" we skip "for" */
7414 if (!pi->next->cmds[0].argv) {
7415 G.last_exitcode = rcode = EXIT_SUCCESS;
7416 debug_printf_exec(": null FOR: exitcode EXIT_SUCCESS\n");
7419 vals = pi->next->cmds[0].argv;
7420 } /* else: "for var; do..." -> assume "$@" list */
7421 /* create list of variable values */
7422 debug_print_strings("for_list made from", vals);
7423 for_list = expand_strvec_to_strvec(vals);
7424 for_lcur = for_list;
7425 debug_print_strings("for_list", for_list);
7428 /* "for" loop is over, clean up */
7434 /* Insert next value from for_lcur */
7435 /* note: *for_lcur already has quotes removed, $var expanded, etc */
7436 set_local_var(xasprintf("%s=%s", pi->cmds[0].argv[0], *for_lcur++), /*exp:*/ 0, /*lvl:*/ 0, /*ro:*/ 0);
7439 if (rword == RES_IN) {
7440 continue; /* "for v IN list;..." - "in" has no cmds anyway */
7442 if (rword == RES_DONE) {
7443 continue; /* "done" has no cmds too */
7446 #if ENABLE_HUSH_CASE
7447 if (rword == RES_CASE) {
7448 case_word = expand_strvec_to_string(pi->cmds->argv);
7451 if (rword == RES_MATCH) {
7454 if (!case_word) /* "case ... matched_word) ... WORD)": we executed selected branch, stop */
7456 /* all prev words didn't match, does this one match? */
7457 argv = pi->cmds->argv;
7459 char *pattern = expand_string_to_string(*argv, /*unbackslash:*/ 1);
7460 /* TODO: which FNM_xxx flags to use? */
7461 cond_code = (fnmatch(pattern, case_word, /*flags:*/ 0) != 0);
7463 if (cond_code == 0) { /* match! we will execute this branch */
7464 free(case_word); /* make future "word)" stop */
7472 if (rword == RES_CASE_BODY) { /* inside of a case branch */
7474 continue; /* not matched yet, skip this pipe */
7477 /* Just pressing <enter> in shell should check for jobs.
7478 * OTOH, in non-interactive shell this is useless
7479 * and only leads to extra job checks */
7480 if (pi->num_cmds == 0) {
7481 if (G_interactive_fd)
7482 goto check_jobs_and_continue;
7486 /* After analyzing all keywords and conditions, we decided
7487 * to execute this pipe. NB: have to do checkjobs(NULL)
7488 * after run_pipe to collect any background children,
7489 * even if list execution is to be stopped. */
7490 debug_printf_exec(": run_pipe with %d members\n", pi->num_cmds);
7493 #if ENABLE_HUSH_LOOPS
7494 G.flag_break_continue = 0;
7496 rcode = r = run_pipe(pi); /* NB: rcode is a smallint */
7498 /* We ran a builtin, function, or group.
7499 * rcode is already known
7500 * and we don't need to wait for anything. */
7501 G.last_exitcode = rcode;
7502 debug_printf_exec(": builtin/func exitcode %d\n", rcode);
7503 check_and_run_traps();
7504 #if ENABLE_HUSH_LOOPS
7505 /* Was it "break" or "continue"? */
7506 if (G.flag_break_continue) {
7507 smallint fbc = G.flag_break_continue;
7508 /* We might fall into outer *loop*,
7509 * don't want to break it too */
7511 G.depth_break_continue--;
7512 if (G.depth_break_continue == 0)
7513 G.flag_break_continue = 0;
7514 /* else: e.g. "continue 2" should *break* once, *then* continue */
7515 } /* else: "while... do... { we are here (innermost list is not a loop!) };...done" */
7516 if (G.depth_break_continue != 0 || fbc == BC_BREAK) {
7520 /* "continue": simulate end of loop */
7525 #if ENABLE_HUSH_FUNCTIONS
7526 if (G.flag_return_in_progress == 1) {
7531 } else if (pi->followup == PIPE_BG) {
7532 /* What does bash do with attempts to background builtins? */
7533 /* even bash 3.2 doesn't do that well with nested bg:
7534 * try "{ { sleep 10; echo DEEP; } & echo HERE; } &".
7535 * I'm NOT treating inner &'s as jobs */
7536 check_and_run_traps();
7538 if (G.run_list_level == 1)
7541 /* Last command's pid goes to $! */
7542 G.last_bg_pid = pi->cmds[pi->num_cmds - 1].pid;
7543 G.last_exitcode = rcode = EXIT_SUCCESS;
7544 debug_printf_exec(": cmd&: exitcode EXIT_SUCCESS\n");
7547 if (G.run_list_level == 1 && G_interactive_fd) {
7548 /* Waits for completion, then fg's main shell */
7549 rcode = checkjobs_and_fg_shell(pi);
7550 debug_printf_exec(": checkjobs_and_fg_shell exitcode %d\n", rcode);
7551 check_and_run_traps();
7554 { /* This one just waits for completion */
7555 rcode = checkjobs(pi);
7556 debug_printf_exec(": checkjobs exitcode %d\n", rcode);
7557 check_and_run_traps();
7559 G.last_exitcode = rcode;
7563 /* Analyze how result affects subsequent commands */
7565 if (rword == RES_IF || rword == RES_ELIF)
7568 check_jobs_and_continue:
7570 dont_check_jobs_but_continue: ;
7571 #if ENABLE_HUSH_LOOPS
7572 /* Beware of "while false; true; do ..."! */
7574 && (pi->next->res_word == RES_DO || pi->next->res_word == RES_DONE)
7575 /* check for RES_DONE is needed for "while ...; do \n done" case */
7577 if (rword == RES_WHILE) {
7579 /* "while false; do...done" - exitcode 0 */
7580 G.last_exitcode = rcode = EXIT_SUCCESS;
7581 debug_printf_exec(": while expr is false: breaking (exitcode:EXIT_SUCCESS)\n");
7585 if (rword == RES_UNTIL) {
7587 debug_printf_exec(": until expr is true: breaking\n");
7598 #if ENABLE_HUSH_LOOPS
7603 #if ENABLE_HUSH_CASE
7607 debug_printf_exec("run_list lvl %d return %d\n", G.run_list_level + 1, rcode);
7611 /* Select which version we will use */
7612 static int run_and_free_list(struct pipe *pi)
7615 debug_printf_exec("run_and_free_list entered\n");
7616 if (!G.o_opt[OPT_O_NOEXEC]) {
7617 debug_printf_exec(": run_list: 1st pipe with %d cmds\n", pi->num_cmds);
7618 rcode = run_list(pi);
7620 /* free_pipe_list has the side effect of clearing memory.
7621 * In the long run that function can be merged with run_list,
7622 * but doing that now would hobble the debugging effort. */
7624 debug_printf_exec("run_and_free_list return %d\n", rcode);
7629 static void install_sighandlers(unsigned mask)
7631 sighandler_t old_handler;
7633 while ((mask >>= 1) != 0) {
7637 old_handler = install_sighandler(sig, pick_sighandler(sig));
7638 /* POSIX allows shell to re-enable SIGCHLD
7639 * even if it was SIG_IGN on entry.
7640 * Therefore we skip IGN check for it:
7644 if (old_handler == SIG_IGN) {
7645 /* oops... restore back to IGN, and record this fact */
7646 install_sighandler(sig, old_handler);
7648 G.traps = xzalloc(sizeof(G.traps[0]) * NSIG);
7650 G.traps[sig] = xzalloc(1); /* == xstrdup(""); */
7655 /* Called a few times only (or even once if "sh -c") */
7656 static void install_special_sighandlers(void)
7660 /* Which signals are shell-special? */
7661 mask = (1 << SIGQUIT) | (1 << SIGCHLD);
7662 if (G_interactive_fd) {
7663 mask |= SPECIAL_INTERACTIVE_SIGS;
7664 if (G_saved_tty_pgrp) /* we have ctty, job control sigs work */
7665 mask |= SPECIAL_JOBSTOP_SIGS;
7667 /* Careful, do not re-install handlers we already installed */
7668 if (G.special_sig_mask != mask) {
7669 unsigned diff = mask & ~G.special_sig_mask;
7670 G.special_sig_mask = mask;
7671 install_sighandlers(diff);
7677 /* Set handlers to restore tty pgrp and exit */
7678 static void install_fatal_sighandlers(void)
7682 /* We will restore tty pgrp on these signals */
7684 + (1 << SIGILL ) * HUSH_DEBUG
7685 + (1 << SIGFPE ) * HUSH_DEBUG
7686 + (1 << SIGBUS ) * HUSH_DEBUG
7687 + (1 << SIGSEGV) * HUSH_DEBUG
7688 + (1 << SIGTRAP) * HUSH_DEBUG
7690 /* bash 3.2 seems to handle these just like 'fatal' ones */
7693 /* if we are interactive, SIGHUP, SIGTERM and SIGINT are special sigs.
7694 * if we aren't interactive... but in this case
7695 * we never want to restore pgrp on exit, and this fn is not called
7697 /*+ (1 << SIGHUP )*/
7698 /*+ (1 << SIGTERM)*/
7699 /*+ (1 << SIGINT )*/
7701 G_fatal_sig_mask = mask;
7703 install_sighandlers(mask);
7707 static int set_mode(int state, char mode, const char *o_opt)
7712 G.o_opt[OPT_O_NOEXEC] = state;
7715 IF_HUSH_MODE_X(G_x_mode = state;)
7719 /* "set -+o" without parameter.
7720 * in bash, set -o produces this output:
7724 * We always use the second form.
7726 const char *p = o_opt_strings;
7729 printf("set %co %s\n", (G.o_opt[idx] ? '-' : '+'), p);
7735 idx = index_in_strings(o_opt_strings, o_opt);
7737 G.o_opt[idx] = state;
7741 return EXIT_FAILURE;
7743 return EXIT_SUCCESS;
7746 int hush_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
7747 int hush_main(int argc, char **argv)
7750 OPT_login = (1 << 0),
7754 unsigned builtin_argc;
7756 struct variable *cur_var;
7757 struct variable *shell_ver;
7760 if (EXIT_SUCCESS != 0) /* if EXIT_SUCCESS == 0, it is already done */
7761 G.last_exitcode = EXIT_SUCCESS;
7762 #if ENABLE_HUSH_FAST
7763 G.count_SIGCHLD++; /* ensure it is != G.handled_SIGCHLD */
7766 G.argv0_for_re_execing = argv[0];
7768 /* Deal with HUSH_VERSION */
7769 shell_ver = xzalloc(sizeof(*shell_ver));
7770 shell_ver->flg_export = 1;
7771 shell_ver->flg_read_only = 1;
7772 /* Code which handles ${var<op>...} needs writable values for all variables,
7773 * therefore we xstrdup: */
7774 shell_ver->varstr = xstrdup(hush_version_str);
7775 /* Create shell local variables from the values
7776 * currently living in the environment */
7777 debug_printf_env("unsetenv '%s'\n", "HUSH_VERSION");
7778 unsetenv("HUSH_VERSION"); /* in case it exists in initial env */
7779 G.top_var = shell_ver;
7780 cur_var = G.top_var;
7783 char *value = strchr(*e, '=');
7784 if (value) { /* paranoia */
7785 cur_var->next = xzalloc(sizeof(*cur_var));
7786 cur_var = cur_var->next;
7787 cur_var->varstr = *e;
7788 cur_var->max_len = strlen(*e);
7789 cur_var->flg_export = 1;
7793 /* (Re)insert HUSH_VERSION into env (AFTER we scanned the env!) */
7794 debug_printf_env("putenv '%s'\n", shell_ver->varstr);
7795 putenv(shell_ver->varstr);
7798 set_pwd_var(/*exp:*/ 1);
7800 #if ENABLE_HUSH_BASH_COMPAT
7801 /* Set (but not export) HOSTNAME unless already set */
7802 if (!get_local_var_value("HOSTNAME")) {
7805 set_local_var_from_halves("HOSTNAME", uts.nodename);
7807 /* bash also exports SHLVL and _,
7808 * and sets (but doesn't export) the following variables:
7810 * BASH_VERSINFO=([0]="3" [1]="2" [2]="0" [3]="1" [4]="release" [5]="i386-pc-linux-gnu")
7811 * BASH_VERSION='3.2.0(1)-release'
7813 * MACHTYPE=i386-pc-linux-gnu
7815 * PPID=<NNNNN> - we also do it elsewhere
7826 * PIPESTATUS=([0]="0")
7827 * HISTFILE=/<xxx>/.bash_history
7831 * PATH=/usr/gnu/bin:/usr/local/bin:/bin:/usr/bin:.
7833 * SHELLOPTS=braceexpand:emacs:hashall:histexpand:history:interactive-comments:monitor
7844 #if ENABLE_FEATURE_EDITING
7845 G.line_input_state = new_line_input_t(FOR_SHELL);
7848 /* Initialize some more globals to non-zero values */
7849 cmdedit_update_prompt();
7851 if (setjmp(die_jmp)) {
7852 /* xfunc has failed! die die die */
7853 /* no EXIT traps, this is an escape hatch! */
7855 hush_exit(xfunc_error_retval);
7858 /* Shell is non-interactive at first. We need to call
7859 * install_special_sighandlers() if we are going to execute "sh <script>",
7860 * "sh -c <cmds>" or login shell's /etc/profile and friends.
7861 * If we later decide that we are interactive, we run install_special_sighandlers()
7862 * in order to intercept (more) signals.
7866 /* http://www.opengroup.org/onlinepubs/9699919799/utilities/sh.html */
7867 flags = (argv[0] && argv[0][0] == '-') ? OPT_login : 0;
7870 opt = getopt(argc, argv, "+c:xinsl"
7873 # if ENABLE_HUSH_FUNCTIONS
7883 * sh ... -c 'script'
7884 * sh ... -c 'script' ARG0 [ARG1...]
7885 * On NOMMU, if builtin_argc != 0,
7886 * sh ... -c 'builtin' BARGV... "" ARG0 [ARG1...]
7887 * "" needs to be replaced with NULL
7888 * and BARGV vector fed to builtin function.
7889 * Note: the form without ARG0 never happens:
7890 * sh ... -c 'builtin' BARGV... ""
7893 G.root_pid = getpid();
7894 G.root_ppid = getppid();
7896 G.global_argv = argv + optind;
7897 G.global_argc = argc - optind;
7899 /* -c 'builtin' [BARGV...] "" ARG0 [ARG1...] */
7900 const struct built_in_command *x;
7902 install_special_sighandlers();
7903 x = find_builtin(optarg);
7904 if (x) { /* paranoia */
7905 G.global_argc -= builtin_argc; /* skip [BARGV...] "" */
7906 G.global_argv += builtin_argc;
7907 G.global_argv[-1] = NULL; /* replace "" */
7909 G.last_exitcode = x->b_function(argv + optind - 1);
7913 if (!G.global_argv[0]) {
7914 /* -c 'script' (no params): prevent empty $0 */
7915 G.global_argv--; /* points to argv[i] of 'script' */
7916 G.global_argv[0] = argv[0];
7918 } /* else -c 'script' ARG0 [ARG1...]: $0 is ARG0 */
7919 install_special_sighandlers();
7920 parse_and_run_string(optarg);
7923 /* Well, we cannot just declare interactiveness,
7924 * we have to have some stuff (ctty, etc) */
7925 /* G_interactive_fd++; */
7928 /* "-s" means "read from stdin", but this is how we always
7929 * operate, so simply do nothing here. */
7935 case '<': /* "big heredoc" support */
7936 full_write1_str(optarg);
7939 unsigned long long empty_trap_mask;
7941 G.root_pid = bb_strtou(optarg, &optarg, 16);
7943 G.root_ppid = bb_strtou(optarg, &optarg, 16);
7945 G.last_bg_pid = bb_strtou(optarg, &optarg, 16);
7947 G.last_exitcode = bb_strtou(optarg, &optarg, 16);
7949 builtin_argc = bb_strtou(optarg, &optarg, 16);
7951 empty_trap_mask = bb_strtoull(optarg, &optarg, 16);
7952 if (empty_trap_mask != 0) {
7954 install_special_sighandlers();
7955 G.traps = xzalloc(sizeof(G.traps[0]) * NSIG);
7956 for (sig = 1; sig < NSIG; sig++) {
7957 if (empty_trap_mask & (1LL << sig)) {
7958 G.traps[sig] = xzalloc(1); /* == xstrdup(""); */
7959 install_sighandler(sig, SIG_IGN);
7963 # if ENABLE_HUSH_LOOPS
7965 G.depth_of_loop = bb_strtou(optarg, &optarg, 16);
7971 set_local_var(xstrdup(optarg), /*exp:*/ 0, /*lvl:*/ 0, /*ro:*/ opt == 'R');
7973 # if ENABLE_HUSH_FUNCTIONS
7975 struct function *funcp = new_function(optarg);
7976 /* funcp->name is already set to optarg */
7977 /* funcp->body is set to NULL. It's a special case. */
7978 funcp->body_as_string = argv[optind];
7986 if (set_mode(1, opt, NULL) == 0) /* no error */
7990 fprintf(stderr, "Usage: sh [FILE]...\n"
7991 " or: sh -c command [args]...\n\n");
7997 } /* option parsing loop */
7999 /* Skip options. Try "hush -l": $1 should not be "-l"! */
8000 G.global_argc = argc - (optind - 1);
8001 G.global_argv = argv + (optind - 1);
8002 G.global_argv[0] = argv[0];
8005 G.root_pid = getpid();
8006 G.root_ppid = getppid();
8009 /* If we are login shell... */
8010 if (flags & OPT_login) {
8012 debug_printf("sourcing /etc/profile\n");
8013 input = fopen_for_read("/etc/profile");
8014 if (input != NULL) {
8015 close_on_exec_on(fileno(input));
8016 install_special_sighandlers();
8017 parse_and_run_file(input);
8020 /* bash: after sourcing /etc/profile,
8021 * tries to source (in the given order):
8022 * ~/.bash_profile, ~/.bash_login, ~/.profile,
8023 * stopping on first found. --noprofile turns this off.
8024 * bash also sources ~/.bash_logout on exit.
8025 * If called as sh, skips .bash_XXX files.
8029 if (G.global_argv[1]) {
8032 * "bash <script>" (which is never interactive (unless -i?))
8033 * sources $BASH_ENV here (without scanning $PATH).
8034 * If called as sh, does the same but with $ENV.
8038 debug_printf("running script '%s'\n", G.global_argv[0]);
8039 input = xfopen_for_read(G.global_argv[0]);
8040 close_on_exec_on(fileno(input));
8041 install_special_sighandlers();
8042 parse_and_run_file(input);
8043 #if ENABLE_FEATURE_CLEAN_UP
8049 /* Up to here, shell was non-interactive. Now it may become one.
8050 * NB: don't forget to (re)run install_special_sighandlers() as needed.
8053 /* A shell is interactive if the '-i' flag was given,
8054 * or if all of the following conditions are met:
8056 * no arguments remaining or the -s flag given
8057 * standard input is a terminal
8058 * standard output is a terminal
8059 * Refer to Posix.2, the description of the 'sh' utility.
8062 if (isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)) {
8063 G_saved_tty_pgrp = tcgetpgrp(STDIN_FILENO);
8064 debug_printf("saved_tty_pgrp:%d\n", G_saved_tty_pgrp);
8065 if (G_saved_tty_pgrp < 0)
8066 G_saved_tty_pgrp = 0;
8068 /* try to dup stdin to high fd#, >= 255 */
8069 G_interactive_fd = fcntl(STDIN_FILENO, F_DUPFD, 255);
8070 if (G_interactive_fd < 0) {
8071 /* try to dup to any fd */
8072 G_interactive_fd = dup(STDIN_FILENO);
8073 if (G_interactive_fd < 0) {
8075 G_interactive_fd = 0;
8076 G_saved_tty_pgrp = 0;
8079 // TODO: track & disallow any attempts of user
8080 // to (inadvertently) close/redirect G_interactive_fd
8082 debug_printf("interactive_fd:%d\n", G_interactive_fd);
8083 if (G_interactive_fd) {
8084 close_on_exec_on(G_interactive_fd);
8086 if (G_saved_tty_pgrp) {
8087 /* If we were run as 'hush &', sleep until we are
8088 * in the foreground (tty pgrp == our pgrp).
8089 * If we get started under a job aware app (like bash),
8090 * make sure we are now in charge so we don't fight over
8091 * who gets the foreground */
8093 pid_t shell_pgrp = getpgrp();
8094 G_saved_tty_pgrp = tcgetpgrp(G_interactive_fd);
8095 if (G_saved_tty_pgrp == shell_pgrp)
8097 /* send TTIN to ourself (should stop us) */
8098 kill(- shell_pgrp, SIGTTIN);
8102 /* Install more signal handlers */
8103 install_special_sighandlers();
8105 if (G_saved_tty_pgrp) {
8106 /* Set other signals to restore saved_tty_pgrp */
8107 install_fatal_sighandlers();
8108 /* Put ourselves in our own process group
8109 * (bash, too, does this only if ctty is available) */
8110 bb_setpgrp(); /* is the same as setpgid(our_pid, our_pid); */
8111 /* Grab control of the terminal */
8112 tcsetpgrp(G_interactive_fd, getpid());
8114 /* -1 is special - makes xfuncs longjmp, not exit
8115 * (we reset die_sleep = 0 whereever we [v]fork) */
8116 enable_restore_tty_pgrp_on_exit(); /* sets die_sleep = -1 */
8118 # if ENABLE_HUSH_SAVEHISTORY && MAX_HISTORY > 0
8120 const char *hp = get_local_var_value("HISTFILE");
8122 hp = get_local_var_value("HOME");
8124 hp = concat_path_file(hp, ".hush_history");
8129 G.line_input_state->hist_file = hp;
8130 //set_local_var(xasprintf("HISTFILE=%s", ...));
8132 # if ENABLE_FEATURE_SH_HISTFILESIZE
8133 hp = get_local_var_value("HISTFILESIZE");
8134 G.line_input_state->max_history = size_from_HISTFILESIZE(hp);
8139 install_special_sighandlers();
8141 #elif ENABLE_HUSH_INTERACTIVE
8142 /* No job control compiled in, only prompt/line editing */
8143 if (isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)) {
8144 G_interactive_fd = fcntl(STDIN_FILENO, F_DUPFD, 255);
8145 if (G_interactive_fd < 0) {
8146 /* try to dup to any fd */
8147 G_interactive_fd = dup(STDIN_FILENO);
8148 if (G_interactive_fd < 0)
8150 G_interactive_fd = 0;
8153 if (G_interactive_fd) {
8154 close_on_exec_on(G_interactive_fd);
8156 install_special_sighandlers();
8158 /* We have interactiveness code disabled */
8159 install_special_sighandlers();
8162 * if interactive but not a login shell, sources ~/.bashrc
8163 * (--norc turns this off, --rcfile <file> overrides)
8166 if (!ENABLE_FEATURE_SH_EXTRA_QUIET && G_interactive_fd) {
8167 /* note: ash and hush share this string */
8168 printf("\n\n%s %s\n"
8169 IF_HUSH_HELP("Enter 'help' for a list of built-in commands.\n")
8172 "hush - the humble shell"
8176 parse_and_run_file(stdin);
8179 hush_exit(G.last_exitcode);
8184 int msh_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
8185 int msh_main(int argc, char **argv)
8187 //bb_error_msg("msh is deprecated, please use hush instead");
8188 return hush_main(argc, argv);
8196 static int FAST_FUNC builtin_true(char **argv UNUSED_PARAM)
8201 static int run_applet_main(char **argv, int (*applet_main_func)(int argc, char **argv))
8208 return applet_main_func(argc, argv - argc);
8211 static int FAST_FUNC builtin_test(char **argv)
8213 return run_applet_main(argv, test_main);
8216 static int FAST_FUNC builtin_echo(char **argv)
8218 return run_applet_main(argv, echo_main);
8222 static int FAST_FUNC builtin_printf(char **argv)
8224 return run_applet_main(argv, printf_main);
8228 static char **skip_dash_dash(char **argv)
8231 if (argv[0] && argv[0][0] == '-' && argv[0][1] == '-' && argv[0][2] == '\0')
8236 static int FAST_FUNC builtin_eval(char **argv)
8238 int rcode = EXIT_SUCCESS;
8240 argv = skip_dash_dash(argv);
8242 char *str = expand_strvec_to_string(argv);
8244 * eval "echo Hi; done" ("done" is syntax error):
8245 * "echo Hi" will not execute too.
8247 parse_and_run_string(str);
8249 rcode = G.last_exitcode;
8254 static int FAST_FUNC builtin_cd(char **argv)
8258 argv = skip_dash_dash(argv);
8260 if (newdir == NULL) {
8261 /* bash does nothing (exitcode 0) if HOME is ""; if it's unset,
8262 * bash says "bash: cd: HOME not set" and does nothing
8265 const char *home = get_local_var_value("HOME");
8266 newdir = home ? home : "/";
8268 if (chdir(newdir)) {
8269 /* Mimic bash message exactly */
8270 bb_perror_msg("cd: %s", newdir);
8271 return EXIT_FAILURE;
8273 /* Read current dir (get_cwd(1) is inside) and set PWD.
8274 * Note: do not enforce exporting. If PWD was unset or unexported,
8275 * set it again, but do not export. bash does the same.
8277 set_pwd_var(/*exp:*/ 0);
8278 return EXIT_SUCCESS;
8281 static int FAST_FUNC builtin_exec(char **argv)
8283 argv = skip_dash_dash(argv);
8284 if (argv[0] == NULL)
8285 return EXIT_SUCCESS; /* bash does this */
8287 /* Careful: we can end up here after [v]fork. Do not restore
8288 * tty pgrp then, only top-level shell process does that */
8289 if (G_saved_tty_pgrp && getpid() == G.root_pid)
8290 tcsetpgrp(G_interactive_fd, G_saved_tty_pgrp);
8292 /* TODO: if exec fails, bash does NOT exit! We do.
8293 * We'll need to undo trap cleanup (it's inside execvp_or_die)
8294 * and tcsetpgrp, and this is inherently racy.
8296 execvp_or_die(argv);
8299 static int FAST_FUNC builtin_exit(char **argv)
8301 debug_printf_exec("%s()\n", __func__);
8303 /* interactive bash:
8304 * # trap "echo EEE" EXIT
8307 * There are stopped jobs.
8308 * (if there are _stopped_ jobs, running ones don't count)
8311 * EEE (then bash exits)
8313 * TODO: we can use G.exiting = -1 as indicator "last cmd was exit"
8316 /* note: EXIT trap is run by hush_exit */
8317 argv = skip_dash_dash(argv);
8318 if (argv[0] == NULL)
8319 hush_exit(G.last_exitcode);
8320 /* mimic bash: exit 123abc == exit 255 + error msg */
8321 xfunc_error_retval = 255;
8322 /* bash: exit -2 == exit 254, no error msg */
8323 hush_exit(xatoi(argv[0]) & 0xff);
8326 static void print_escaped(const char *s)
8331 const char *p = strchrnul(s, '\'');
8332 /* print 'xxxx', possibly just '' */
8333 printf("'%.*s'", (int)(p - s), s);
8338 /* s points to '; print "'''...'''" */
8340 do putchar('\''); while (*++s == '\'');
8345 #if !ENABLE_HUSH_LOCAL
8346 #define helper_export_local(argv, exp, lvl) \
8347 helper_export_local(argv, exp)
8349 static void helper_export_local(char **argv, int exp, int lvl)
8353 char *name_end = strchrnul(name, '=');
8355 /* So far we do not check that name is valid (TODO?) */
8357 if (*name_end == '\0') {
8358 struct variable *var, **vpp;
8360 vpp = get_ptr_to_local_var(name, name_end - name);
8361 var = vpp ? *vpp : NULL;
8363 if (exp == -1) { /* unexporting? */
8364 /* export -n NAME (without =VALUE) */
8366 var->flg_export = 0;
8367 debug_printf_env("%s: unsetenv '%s'\n", __func__, name);
8369 } /* else: export -n NOT_EXISTING_VAR: no-op */
8372 if (exp == 1) { /* exporting? */
8373 /* export NAME (without =VALUE) */
8375 var->flg_export = 1;
8376 debug_printf_env("%s: putenv '%s'\n", __func__, var->varstr);
8377 putenv(var->varstr);
8381 /* Exporting non-existing variable.
8382 * bash does not put it in environment,
8383 * but remembers that it is exported,
8384 * and does put it in env when it is set later.
8385 * We just set it to "" and export. */
8386 /* Or, it's "local NAME" (without =VALUE).
8387 * bash sets the value to "". */
8388 name = xasprintf("%s=", name);
8390 /* (Un)exporting/making local NAME=VALUE */
8391 name = xstrdup(name);
8393 set_local_var(name, /*exp:*/ exp, /*lvl:*/ lvl, /*ro:*/ 0);
8397 static int FAST_FUNC builtin_export(char **argv)
8399 unsigned opt_unexport;
8401 #if ENABLE_HUSH_EXPORT_N
8402 /* "!": do not abort on errors */
8403 opt_unexport = getopt32(argv, "!n");
8404 if (opt_unexport == (uint32_t)-1)
8405 return EXIT_FAILURE;
8412 if (argv[0] == NULL) {
8419 /* ash emits: export VAR='VAL'
8420 * bash: declare -x VAR="VAL"
8421 * we follow ash example */
8422 const char *s = *e++;
8423 const char *p = strchr(s, '=');
8425 if (!p) /* wtf? take next variable */
8428 printf("export %.*s", (int)(p - s) + 1, s);
8429 print_escaped(p + 1);
8433 /*fflush_all(); - done after each builtin anyway */
8435 return EXIT_SUCCESS;
8438 helper_export_local(argv, (opt_unexport ? -1 : 1), 0);
8440 return EXIT_SUCCESS;
8443 #if ENABLE_HUSH_LOCAL
8444 static int FAST_FUNC builtin_local(char **argv)
8446 if (G.func_nest_level == 0) {
8447 bb_error_msg("%s: not in a function", argv[0]);
8448 return EXIT_FAILURE; /* bash compat */
8450 helper_export_local(argv, 0, G.func_nest_level);
8451 return EXIT_SUCCESS;
8455 static int FAST_FUNC builtin_trap(char **argv)
8461 G.traps = xzalloc(sizeof(G.traps[0]) * NSIG);
8466 /* No args: print all trapped */
8467 for (i = 0; i < NSIG; ++i) {
8470 print_escaped(G.traps[i]);
8471 /* note: bash adds "SIG", but only if invoked
8472 * as "bash". If called as "sh", or if set -o posix,
8473 * then it prints short signal names.
8474 * We are printing short names: */
8475 printf(" %s\n", get_signame(i));
8478 /*fflush_all(); - done after each builtin anyway */
8479 return EXIT_SUCCESS;
8483 /* If first arg is a number: reset all specified signals */
8484 sig = bb_strtou(*argv, NULL, 10);
8490 sighandler_t handler;
8492 sig = get_signum(*argv++);
8493 if (sig < 0 || sig >= NSIG) {
8495 /* Mimic bash message exactly */
8496 bb_perror_msg("trap: %s: invalid signal specification", argv[-1]);
8501 G.traps[sig] = xstrdup(new_cmd);
8503 debug_printf("trap: setting SIG%s (%i) to '%s'\n",
8504 get_signame(sig), sig, G.traps[sig]);
8506 /* There is no signal for 0 (EXIT) */
8511 handler = (new_cmd[0] ? record_pending_signo : SIG_IGN);
8513 /* We are removing trap handler */
8514 handler = pick_sighandler(sig);
8515 install_sighandler(sig, handler);
8520 if (!argv[1]) { /* no second arg */
8521 bb_error_msg("trap: invalid arguments");
8522 return EXIT_FAILURE;
8525 /* First arg is "-": reset all specified to default */
8526 /* First arg is "--": skip it, the rest is "handler SIGs..." */
8527 /* Everything else: set arg as signal handler
8528 * (includes "" case, which ignores signal) */
8529 if (argv[0][0] == '-') {
8530 if (argv[0][1] == '\0') { /* "-" */
8531 /* new_cmd remains NULL: "reset these sigs" */
8534 if (argv[0][1] == '-' && argv[0][2] == '\0') { /* "--" */
8537 /* else: "-something", no special meaning */
8542 goto process_sig_list;
8545 /* http://www.opengroup.org/onlinepubs/9699919799/utilities/type.html */
8546 static int FAST_FUNC builtin_type(char **argv)
8548 int ret = EXIT_SUCCESS;
8554 if (0) {} /* make conditional compile easier below */
8555 /*else if (find_alias(*argv))
8556 type = "an alias";*/
8557 #if ENABLE_HUSH_FUNCTIONS
8558 else if (find_function(*argv))
8559 type = "a function";
8561 else if (find_builtin(*argv))
8562 type = "a shell builtin";
8563 else if ((path = find_in_path(*argv)) != NULL)
8566 bb_error_msg("type: %s: not found", *argv);
8571 printf("%s is %s\n", *argv, type);
8579 /* built-in 'fg' and 'bg' handler */
8580 static int FAST_FUNC builtin_fg_bg(char **argv)
8585 if (!G_interactive_fd)
8586 return EXIT_FAILURE;
8588 /* If they gave us no args, assume they want the last backgrounded task */
8590 for (pi = G.job_list; pi; pi = pi->next) {
8591 if (pi->jobid == G.last_jobid) {
8595 bb_error_msg("%s: no current job", argv[0]);
8596 return EXIT_FAILURE;
8598 if (sscanf(argv[1], "%%%d", &jobnum) != 1) {
8599 bb_error_msg("%s: bad argument '%s'", argv[0], argv[1]);
8600 return EXIT_FAILURE;
8602 for (pi = G.job_list; pi; pi = pi->next) {
8603 if (pi->jobid == jobnum) {
8607 bb_error_msg("%s: %d: no such job", argv[0], jobnum);
8608 return EXIT_FAILURE;
8610 /* TODO: bash prints a string representation
8611 * of job being foregrounded (like "sleep 1 | cat") */
8612 if (argv[0][0] == 'f' && G_saved_tty_pgrp) {
8613 /* Put the job into the foreground. */
8614 tcsetpgrp(G_interactive_fd, pi->pgrp);
8617 /* Restart the processes in the job */
8618 debug_printf_jobs("reviving %d procs, pgrp %d\n", pi->num_cmds, pi->pgrp);
8619 for (i = 0; i < pi->num_cmds; i++) {
8620 debug_printf_jobs("reviving pid %d\n", pi->cmds[i].pid);
8622 pi->stopped_cmds = 0;
8624 i = kill(- pi->pgrp, SIGCONT);
8626 if (errno == ESRCH) {
8627 delete_finished_bg_job(pi);
8628 return EXIT_SUCCESS;
8630 bb_perror_msg("kill (SIGCONT)");
8633 if (argv[0][0] == 'f') {
8635 return checkjobs_and_fg_shell(pi);
8637 return EXIT_SUCCESS;
8641 #if ENABLE_HUSH_HELP
8642 static int FAST_FUNC builtin_help(char **argv UNUSED_PARAM)
8644 const struct built_in_command *x;
8647 "Built-in commands:\n"
8648 "------------------\n");
8649 for (x = bltins1; x != &bltins1[ARRAY_SIZE(bltins1)]; x++) {
8651 printf("%-10s%s\n", x->b_cmd, x->b_descr);
8654 return EXIT_SUCCESS;
8658 #if MAX_HISTORY && ENABLE_FEATURE_EDITING
8659 static int FAST_FUNC builtin_history(char **argv UNUSED_PARAM)
8661 show_history(G.line_input_state);
8662 return EXIT_SUCCESS;
8667 static int FAST_FUNC builtin_jobs(char **argv UNUSED_PARAM)
8670 const char *status_string;
8672 for (job = G.job_list; job; job = job->next) {
8673 if (job->alive_cmds == job->stopped_cmds)
8674 status_string = "Stopped";
8676 status_string = "Running";
8678 printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->cmdtext);
8680 return EXIT_SUCCESS;
8685 static int FAST_FUNC builtin_memleak(char **argv UNUSED_PARAM)
8690 # ifdef M_TRIM_THRESHOLD
8691 /* Optional. Reduces probability of false positives */
8694 /* Crude attempt to find where "free memory" starts,
8695 * sans fragmentation. */
8697 l = (unsigned long)p;
8700 if (l < (unsigned long)p) l = (unsigned long)p;
8703 if (!G.memleak_value)
8704 G.memleak_value = l;
8706 l -= G.memleak_value;
8713 /* Exitcode is "how many kilobytes we leaked since 1st call" */
8718 static int FAST_FUNC builtin_pwd(char **argv UNUSED_PARAM)
8721 return EXIT_SUCCESS;
8724 /* Interruptibility of read builtin in bash
8725 * (tested on bash-4.2.8 by sending signals (not by ^C)):
8727 * Empty trap makes read ignore corresponding signal, for any signal.
8730 * - terminates non-interactive shell;
8731 * - interrupts read in interactive shell;
8732 * if it has non-empty trap:
8733 * - executes trap and returns to command prompt in interactive shell;
8734 * - executes trap and returns to read in non-interactive shell;
8736 * - is ignored (does not interrupt) read in interactive shell;
8737 * - terminates non-interactive shell;
8738 * if it has non-empty trap:
8739 * - executes trap and returns to read;
8741 * - terminates shell (regardless of interactivity);
8742 * if it has non-empty trap:
8743 * - executes trap and returns to read;
8745 static int FAST_FUNC builtin_read(char **argv)
8755 /* "!": do not abort on errors.
8756 * Option string must start with "sr" to match BUILTIN_READ_xxx
8758 read_flags = getopt32(argv, "!srn:p:t:u:", &opt_n, &opt_p, &opt_t, &opt_u);
8759 if (read_flags == (uint32_t)-1)
8760 return EXIT_FAILURE;
8762 ifs = get_local_var_value("IFS"); /* can be NULL */
8765 r = shell_builtin_read(set_local_var_from_halves,
8775 if ((uintptr_t)r == 1 && errno == EINTR) {
8776 unsigned sig = check_and_run_traps();
8777 if (sig && sig != SIGINT)
8781 if ((uintptr_t)r > 1) {
8782 bb_error_msg("%s", r);
8783 r = (char*)(uintptr_t)1;
8786 return (uintptr_t)r;
8789 /* http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#set
8790 * built-in 'set' handler
8792 * set [-abCefhmnuvx] [-o option] [argument...]
8793 * set [+abCefhmnuvx] [+o option] [argument...]
8794 * set -- [argument...]
8797 * Implementations shall support the options in both their hyphen and
8798 * plus-sign forms. These options can also be specified as options to sh.
8800 * Write out all variables and their values: set
8801 * Set $1, $2, and $3 and set "$#" to 3: set c a b
8802 * Turn on the -x and -v options: set -xv
8803 * Unset all positional parameters: set --
8804 * Set $1 to the value of x, even if it begins with '-' or '+': set -- "$x"
8805 * Set the positional parameters to the expansion of x, even if x expands
8806 * with a leading '-' or '+': set -- $x
8808 * So far, we only support "set -- [argument...]" and some of the short names.
8810 static int FAST_FUNC builtin_set(char **argv)
8813 char **pp, **g_argv;
8814 char *arg = *++argv;
8818 for (e = G.top_var; e; e = e->next)
8820 return EXIT_SUCCESS;
8824 if (strcmp(arg, "--") == 0) {
8828 if (arg[0] != '+' && arg[0] != '-')
8830 for (n = 1; arg[n]; ++n) {
8831 if (set_mode((arg[0] == '-'), arg[n], argv[1]))
8833 if (arg[n] == 'o' && argv[1])
8836 } while ((arg = *++argv) != NULL);
8837 /* Now argv[0] is 1st argument */
8840 return EXIT_SUCCESS;
8843 /* NB: G.global_argv[0] ($0) is never freed/changed */
8844 g_argv = G.global_argv;
8845 if (G.global_args_malloced) {
8851 G.global_args_malloced = 1;
8852 pp = xzalloc(sizeof(pp[0]) * 2);
8853 pp[0] = g_argv[0]; /* retain $0 */
8856 /* This realloc's G.global_argv */
8857 G.global_argv = pp = add_strings_to_strings(g_argv, argv, /*dup:*/ 1);
8864 return EXIT_SUCCESS;
8866 /* Nothing known, so abort */
8868 bb_error_msg("set: %s: invalid option", arg);
8869 return EXIT_FAILURE;
8872 static int FAST_FUNC builtin_shift(char **argv)
8875 argv = skip_dash_dash(argv);
8879 if (n >= 0 && n < G.global_argc) {
8880 if (G.global_args_malloced) {
8883 free(G.global_argv[m++]);
8886 memmove(&G.global_argv[1], &G.global_argv[n+1],
8887 G.global_argc * sizeof(G.global_argv[0]));
8888 return EXIT_SUCCESS;
8890 return EXIT_FAILURE;
8893 static int FAST_FUNC builtin_source(char **argv)
8895 char *arg_path, *filename;
8898 #if ENABLE_HUSH_FUNCTIONS
8902 argv = skip_dash_dash(argv);
8905 /* bash says: "bash: .: filename argument required" */
8906 return 2; /* bash compat */
8909 if (!strchr(filename, '/')) {
8910 arg_path = find_in_path(filename);
8912 filename = arg_path;
8914 input = fopen_or_warn(filename, "r");
8917 /* bb_perror_msg("%s", *argv); - done by fopen_or_warn */
8918 /* POSIX: non-interactive shell should abort here,
8919 * not merely fail. So far no one complained :)
8921 return EXIT_FAILURE;
8923 close_on_exec_on(fileno(input));
8925 #if ENABLE_HUSH_FUNCTIONS
8926 sv_flg = G.flag_return_in_progress;
8927 /* "we are inside sourced file, ok to use return" */
8928 G.flag_return_in_progress = -1;
8931 save_and_replace_G_args(&sv, argv);
8933 parse_and_run_file(input);
8937 restore_G_args(&sv, argv);
8938 #if ENABLE_HUSH_FUNCTIONS
8939 G.flag_return_in_progress = sv_flg;
8942 return G.last_exitcode;
8945 static int FAST_FUNC builtin_umask(char **argv)
8951 argv = skip_dash_dash(argv);
8953 mode_t old_mask = mask;
8956 rc = bb_parse_mode(argv[0], &mask);
8961 * bash: umask: 'q': invalid symbolic mode operator
8962 * bash: umask: 999: octal number out of range
8964 bb_error_msg("%s: invalid mode '%s'", "umask", argv[0]);
8969 printf("%04o\n", (unsigned) mask);
8970 /* fall through and restore mask which we set to 0 */
8974 return !rc; /* rc != 0 - success */
8977 /* http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#unset */
8978 static int FAST_FUNC builtin_unset(char **argv)
8983 /* "!": do not abort on errors */
8984 /* "+": stop at 1st non-option */
8985 opts = getopt32(argv, "!+vf");
8986 if (opts == (unsigned)-1)
8987 return EXIT_FAILURE;
8989 bb_error_msg("unset: -v and -f are exclusive");
8990 return EXIT_FAILURE;
8996 if (!(opts & 2)) { /* not -f */
8997 if (unset_local_var(*argv)) {
8998 /* unset <nonexistent_var> doesn't fail.
8999 * Error is when one tries to unset RO var.
9000 * Message was printed by unset_local_var. */
9004 #if ENABLE_HUSH_FUNCTIONS
9014 /* http://www.opengroup.org/onlinepubs/9699919799/utilities/wait.html */
9015 static int FAST_FUNC builtin_wait(char **argv)
9017 int ret = EXIT_SUCCESS;
9020 argv = skip_dash_dash(argv);
9021 if (argv[0] == NULL) {
9022 /* Don't care about wait results */
9023 /* Note 1: must wait until there are no more children */
9024 /* Note 2: must be interruptible */
9026 * $ sleep 3 & sleep 6 & wait
9031 * $ sleep 3 & sleep 6 & wait
9035 * ^C <-- after ~4 sec from keyboard
9040 sigset_t oldset, allsigs;
9042 /* waitpid is not interruptible by SA_RESTARTed
9043 * signals which we use. Thus, this ugly dance:
9046 /* Make sure possible SIGCHLD is stored in kernel's
9047 * pending signal mask before we call waitpid.
9048 * Or else we may race with SIGCHLD, lose it,
9049 * and get stuck in sigwaitinfo...
9051 sigfillset(&allsigs);
9052 sigprocmask(SIG_SETMASK, &allsigs, &oldset);
9054 if (!sigisemptyset(&G.pending_set)) {
9055 /* Crap! we raced with some signal! */
9060 checkjobs(NULL); /* waitpid(WNOHANG) inside */
9061 if (errno == ECHILD) {
9062 sigprocmask(SIG_SETMASK, &oldset, NULL);
9066 /* Wait for SIGCHLD or any other signal */
9067 //sig = sigwaitinfo(&allsigs, NULL);
9068 /* It is vitally important for sigsuspend that SIGCHLD has non-DFL handler! */
9069 /* Note: sigsuspend invokes signal handler */
9070 sigsuspend(&oldset);
9072 sigprocmask(SIG_SETMASK, &oldset, NULL);
9074 /* So, did we get a signal? */
9076 // raise(sig); /* run handler */
9077 sig = check_and_run_traps();
9078 if (sig /*&& sig != SIGCHLD - always true */) {
9083 /* SIGCHLD, or no signal, or ignored one, such as SIGQUIT. Repeat */
9088 /* This is probably buggy wrt interruptible-ness */
9090 pid_t pid = bb_strtou(*argv, NULL, 10);
9092 /* mimic bash message */
9093 bb_error_msg("wait: '%s': not a pid or valid job spec", *argv);
9094 return EXIT_FAILURE;
9096 if (waitpid(pid, &status, 0) == pid) {
9097 if (WIFSIGNALED(status))
9098 ret = 128 + WTERMSIG(status);
9099 else if (WIFEXITED(status))
9100 ret = WEXITSTATUS(status);
9104 bb_perror_msg("wait %s", *argv);
9113 #if ENABLE_HUSH_LOOPS || ENABLE_HUSH_FUNCTIONS
9114 static unsigned parse_numeric_argv1(char **argv, unsigned def, unsigned def_min)
9117 def = bb_strtou(argv[1], NULL, 10);
9118 if (errno || def < def_min || argv[2]) {
9119 bb_error_msg("%s: bad arguments", argv[0]);
9127 #if ENABLE_HUSH_LOOPS
9128 static int FAST_FUNC builtin_break(char **argv)
9131 if (G.depth_of_loop == 0) {
9132 bb_error_msg("%s: only meaningful in a loop", argv[0]);
9133 return EXIT_SUCCESS; /* bash compat */
9135 G.flag_break_continue++; /* BC_BREAK = 1 */
9137 G.depth_break_continue = depth = parse_numeric_argv1(argv, 1, 1);
9138 if (depth == UINT_MAX)
9139 G.flag_break_continue = BC_BREAK;
9140 if (G.depth_of_loop < depth)
9141 G.depth_break_continue = G.depth_of_loop;
9143 return EXIT_SUCCESS;
9146 static int FAST_FUNC builtin_continue(char **argv)
9148 G.flag_break_continue = 1; /* BC_CONTINUE = 2 = 1+1 */
9149 return builtin_break(argv);
9153 #if ENABLE_HUSH_FUNCTIONS
9154 static int FAST_FUNC builtin_return(char **argv)
9158 if (G.flag_return_in_progress != -1) {
9159 bb_error_msg("%s: not in a function or sourced script", argv[0]);
9160 return EXIT_FAILURE; /* bash compat */
9163 G.flag_return_in_progress = 1;
9166 * out of range: wraps around at 256, does not error out
9167 * non-numeric param:
9168 * f() { false; return qwe; }; f; echo $?
9169 * bash: return: qwe: numeric argument required <== we do this
9170 * 255 <== we also do this
9172 rc = parse_numeric_argv1(argv, G.last_exitcode, 0);