/* Create and destroy argument vectors (argv's) Copyright (C) 1992 Free Software Foundation, Inc. Written by Fred Fish @ Cygnus Support This file is part of the libiberty library. Libiberty is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. Libiberty is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with libiberty; see the file COPYING.LIB. If not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. $Id: argv.c,v 1.1 1994/01/28 12:42:55 pk Exp $ */ /* Create and destroy argument vectors. An argument vector is simply an array of string pointers, terminated by a NULL pointer. */ /* AIX requires this to be the first thing in the file. */ #ifdef __GNUC__ #define alloca __builtin_alloca #else /* not __GNUC__ */ #ifdef sparc #include extern char *__builtin_alloca(); /* Stupid include file doesn't declare it */ #else #ifdef _AIX #pragma alloca #else char *alloca (); #endif #endif /* sparc */ #endif /* not __GNUC__ */ #define isspace(ch) ((ch) == ' ' || (ch) == '\t') #include "alloca-conf.h" /* Routines imported from standard C runtime libraries. */ #ifdef __STDC__ #include extern void *memcpy (void *s1, const void *s2, size_t n); /* 4.11.2.1 */ extern size_t strlen (const char *s); /* 4.11.6.3 */ extern void *malloc (size_t size); /* 4.10.3.3 */ extern void *realloc (void *ptr, size_t size); /* 4.10.3.4 */ extern void free (void *ptr); /* 4.10.3.2 */ extern char *strdup (const char *s); /* Non-ANSI */ #else /* !__STDC__ */ extern char *memcpy (); /* Copy memory region */ extern int strlen (); /* Count length of string */ extern char *malloc (); /* Standard memory allocater */ extern char *realloc (); /* Standard memory reallocator */ extern void free (); /* Free malloc'd memory */ extern char *strdup (); /* Duplicate a string */ #endif /* __STDC__ */ #ifndef NULL #define NULL 0 #endif #ifndef EOS #define EOS '\0' #endif #define INITIAL_MAXARGC 8 /* Number of args + NULL in initial argv */ /* NAME freeargv -- free an argument vector SYNOPSIS void freeargv (vector) char **vector; DESCRIPTION Free an argument vector that was built using buildargv. Simply scans through the vector, freeing the memory for each argument until the terminating NULL is found, and then frees the vector itself. RETURNS No value. */ void freeargv (vector) char **vector; { register char **scan; if (vector != NULL) { for (scan = vector; *scan != NULL; scan++) { free (*scan); } free (vector); } } /* NAME buildargv -- build an argument vector from a string SYNOPSIS char **buildargv (sp) char *sp; DESCRIPTION Given a pointer to a string, parse the string extracting fields separated by whitespace and optionally enclosed within either single or double quotes (which are stripped off), and build a vector of pointers to copies of the string for each field. The input string remains unchanged. All of the memory for the pointer array and copies of the string is obtained from malloc. All of the memory can be returned to the system with the single function call freeargv, which takes the returned result of buildargv, as it's argument. The memory for the argv array is dynamically expanded as necessary. RETURNS Returns a pointer to the argument vector if successful. Returns NULL if the input string pointer is NULL or if there is insufficient memory to complete building the argument vector. NOTES In order to provide a working buffer for extracting arguments into, with appropriate stripping of quotes and translation of backslash sequences, we allocate a working buffer at least as long as the input string. This ensures that we always have enough space in which to work, since the extracted arg is never larger than the input string. If the input is a null string (as opposed to a NULL pointer), then buildarg returns an argv that has one arg, a null string. Argv is always kept terminated with a NULL arg pointer, so it can be passed to freeargv at any time, or returned, as appropriate. */ char **buildargv (input) char *input; { char *arg; char *copybuf; int squote = 0; int dquote = 0; int bsquote = 0; int argc = 0; int maxargc = 0; char **argv = NULL; char **nargv; if (input != NULL) { copybuf = alloca (strlen (input) + 1); /* Is a do{}while to always execute the loop once. Always return an argv, even for null strings. See NOTES above, test case below. */ do { /* Pick off argv[argc] */ while (isspace (*input)) { input++; } if ((maxargc == 0) || (argc >= (maxargc - 1))) { /* argv needs initialization, or expansion */ if (argv == NULL) { maxargc = INITIAL_MAXARGC; nargv = (char **) malloc (maxargc * sizeof (char *)); } else { maxargc *= 2; nargv = (char **) realloc (argv, maxargc * sizeof (char *)); } if (nargv == NULL) { if (argv != NULL) { freeargv (argv); argv = NULL; } break; } argv = nargv; argv[argc] = NULL; } /* Begin scanning arg */ arg = copybuf; while (*input != EOS) { if (isspace (*input) && !squote && !dquote && !bsquote) { break; } else { if (bsquote) { bsquote = 0; *arg++ = *input; } else if (*input == '\\') { bsquote = 1; } else if (squote) { if (*input == '\'') { squote = 0; } else { *arg++ = *input; } } else if (dquote) { if (*input == '"') { dquote = 0; } else { *arg++ = *input; } } else { if (*input == '\'') { squote = 1; } else if (*input == '"') { dquote = 1; } else { *arg++ = *input; } } input++; } } *arg = EOS; argv[argc] = strdup (copybuf); if (argv[argc] == NULL) { freeargv (argv); argv = NULL; break; } argc++; argv[argc] = NULL; } while (*input != EOS); } return (argv); } #ifdef MAIN /* Simple little test driver. */ static char *tests[] = { "a simple command line", "arg 'foo' is single quoted", "arg \"bar\" is double quoted", "arg \"foo bar\" has embedded whitespace", "arg 'Jack said \\'hi\\'' has single quotes", "arg 'Jack said \\\"hi\\\"' has double quotes", "a b c d e f g h i j k l m n o p q r s t u v w x y z 1 2 3 4 5 6 7 8 9", "", NULL }; main () { char **argv; char **test; char **targs; for (test = tests; *test != NULL; test++) { printf ("buildargv(\"%s\")\n", *test); if ((argv = buildargv (*test)) == NULL) { printf ("failed!\n\n"); } else { for (targs = argv; *targs != NULL; targs++) { printf ("\t\"%s\"\n", *targs); } printf ("\n"); } freeargv (argv); } } #endif /* MAIN */