1 /* Parse arguments from a string and prepend them to an argv. 2 3 Copyright (C) 1999-2002, 2006, 2009-2013, 2015-2018 Free Software 4 Foundation, Inc. 5 6 This program is free software: you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation, either version 3 of the License, or 9 (at your option) any later version. 10 11 This program is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 18 19 /* Written by Paul Eggert <eggert@twinsun.com>. */ 20 21 #include <config.h> 22 23 #include "prepargs.h" 24 #include <string.h> 25 #include <sys/types.h> 26 #include <xalloc.h> 27 28 #include <ctype.h> 29 30 /* IN_CTYPE_DOMAIN (C) is nonzero if the unsigned char C can safely be given 31 as an argument to <ctype.h> macros like "isspace". */ 32 #ifdef STDC_HEADERS 33 # define IN_CTYPE_DOMAIN(c) 1 34 #else 35 # define IN_CTYPE_DOMAIN(c) ((c) <= 0177) 36 #endif 37 38 #define ISSPACE(c) (IN_CTYPE_DOMAIN (c) && isspace (c)) 39 40 /* Find the white-space-separated options specified by OPTIONS, and 41 using BUF to store copies of these options, set ARGV[0], ARGV[1], 42 etc. to the option copies. Return the number N of options found. 43 Do not set ARGV[N]. If ARGV is zero, do not store ARGV[0] etc. 44 Backslash can be used to escape whitespace (and backslashes). */ 45 static int 46 prepend_args (char const *options, char *buf, char **argv) 47 { 48 char const *o = options; 49 char *b = buf; 50 int n = 0; 51 52 for (;;) 53 { 54 while (ISSPACE ((unsigned char) *o)) 55 o++; 56 if (!*o) 57 return n; 58 if (argv) 59 argv[n] = b; 60 n++; 61 62 do 63 if ((*b++ = *o++) == '\\' && *o) 64 b[-1] = *o++; 65 while (*o && ! ISSPACE ((unsigned char) *o)); 66 67 *b++ = '\0'; 68 } 69 } 70 71 /* Prepend the whitespace-separated options in OPTIONS to the argument 72 vector of a main program with argument count *PARGC and argument 73 vector *PARGV. */ 74 void 75 prepend_default_options (char const *options, int *pargc, char ***pargv) 76 { 77 if (options) 78 { 79 char *buf = xmalloc (strlen (options) + 1); 80 int prepended = prepend_args (options, buf, (char **) 0); 81 int argc = *pargc; 82 char * const *argv = *pargv; 83 char **pp = xmalloc ((prepended + argc + 1) * sizeof *pp); 84 *pargc = prepended + argc; 85 *pargv = pp; 86 *pp++ = *argv++; 87 pp += prepend_args (options, buf, pp); 88 while ((*pp++ = *argv++)) 89 continue; 90 } 91 } 92