code shrink in check_errors_in_children()

[oweals/busybox.git] / miscutils / dc.c

diff --git a/miscutils/dc.c b/miscutils/dc.c
index ebf357281948fdb2ddbcabde39729dc8c1ae0b64..6bcfbe2493a372ff3555e40c173af843567b3ee3 100644 (file)
--- a/miscutils/dc.c
+++ b/miscutils/dc.c
@@ -1,21 +1,21 @@
 /* vi: set sw=4 ts=4: */
 /*
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
 
 #include "libbb.h"
 #include <math.h>
 
 //usage:#define dc_trivial_usage
-//usage:       "expression..."
+//usage:       "EXPRESSION..."
 //usage:
 //usage:#define dc_full_usage "\n\n"
 //usage:       "Tiny RPN calculator. Operations:\n"
-//usage:       "+, add, -, sub, *, mul, /, div, %, mod, **, exp, and, or, not, eor,\n"
+//usage:       "+, add, -, sub, *, mul, /, div, %, mod, "IF_FEATURE_DC_LIBM("**, exp, ")"and, or, not, xor,\n"
 //usage:       "p - print top of the stack (without popping),\n"
-//usage:       "f - print entire stack, o - pop the value and set output radix\n"
-//usage:       "(value must be 10, 16, 8 or 2).\n"
-//usage:       "Examples: 'dc 2 2 add' -> 4, 'dc 8 8 * 2 2 + /' -> 16\n"
+//usage:       "f - print entire stack,\n"
+//usage:       "o - pop the value and set output radix (must be 10, 16, 8 or 2).\n"
+//usage:       "Examples: 'dc 2 2 add p' -> 4, 'dc 8 8 mul 2 2 + / p' -> 16"
 //usage:
 //usage:#define dc_example_usage
 //usage:       "$ dc 2 2 + p\n"
@@ -219,43 +219,30 @@ static const struct op operators[] = {
        {"p", print_no_pop},
        {"f", print_stack_no_pop},
        {"o", set_output_base},
-       { "", NULL }
 };
 
 static void stack_machine(const char *argument)
 {
-       char *endPointer;
+       char *end;
        double d;
-       const struct op *o = operators;
+       const struct op *o;
 
-       d = strtod(argument, &endPointer);
-
-       if (endPointer != argument && *endPointer == '\0') {
+       d = strtod(argument, &end);
+       if (end != argument && *end == '\0') {
                push(d);
                return;
        }
 
-       while (o->function) {
+       o = operators;
+       do {
                if (strcmp(o->name, argument) == 0) {
                        o->function();
                        return;
                }
                o++;
-       }
-       bb_error_msg_and_die("syntax error at '%s'", argument);
-}
+       } while (o != operators + ARRAY_SIZE(operators));
 
-/* return pointer to next token in buffer and set *buffer to one char
- * past the end of the above mentioned token
- */
-static char *get_token(char **buffer)
-{
-       char *current = skip_whitespace(*buffer);
-       if (*current != '\0') {
-               *buffer = skip_non_whitespace(current);
-               return current;
-       }
-       return NULL;
+       bb_error_msg_and_die("syntax error at '%s'", argument);
 }
 
 int dc_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
@@ -272,16 +259,18 @@ int dc_main(int argc UNUSED_PARAM, char **argv)
                while ((line = xmalloc_fgetline(stdin)) != NULL) {
                        cursor = line;
                        while (1) {
-                               token = get_token(&cursor);
-                               if (!token)
+                               token = skip_whitespace(cursor);
+                               if (*token == '\0')
                                        break;
-                               *cursor++ = '\0';
+                               cursor = skip_non_whitespace(token);
+                               if (*cursor != '\0')
+                                       *cursor++ = '\0';
                                stack_machine(token);
                        }
                        free(line);
                }
        } else {
-               // why? it breaks "dc -2 2 * p"
+               // why? it breaks "dc -2 2 + p"
                //if (argv[0][0] == '-')
                //      bb_show_usage();
                do {