root/anacron/matchrx.c

/*   */

DEFINITIONS

1. match_rx

   1 /*
   2     Anacron - run commands periodically
   3     Copyright (C) 1998  Itai Tzur <itzur@actcom.co.il>
   4     Copyright (C) 1999  Sean 'Shaleh' Perry <shaleh@debian.org>
   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 2 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 along
  17     with this program; if not, write to the Free Software Foundation, Inc.,
  18     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  
  20     The GNU General Public License can also be found in the file
  21     `COPYING' that comes with the Anacron source distribution.
  22 */
  23 
  24 
  25 #include <stdio.h>
  26 #include <regex.h>
  27 #include <stdarg.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include "matchrx.h"
  31 
  32 int
  33 match_rx(const char *rx, char *string, unsigned int n_sub,  /* char **substrings */...)
     /*   */
  34 /* Return 1 if the regular expression "*rx" matches the string "*string",
  35  * 0 if not, -1 on error.
  36  * "Extended" regular expressions are used.
  37  * Additionally, there should be "n_sub" "substrings" arguments.  These,
  38  * if not NULL, and if the match succeeds are set to point to the 
  39  * corresponding substrings of the regexp.
  40  * The original string is changed, and the substrings must not overlap,
  41  * or even be directly adjacent.
  42  * This is not the most efficient, or elegant way of doing this.
  43  */
  44 {
  45         int r, n;
  46         regex_t crx;
  47         va_list va;
  48         char **substring;
  49         regmatch_t *sub_offsets;
  50         sub_offsets = malloc(sizeof(regmatch_t) * (n_sub + 1));
  51         if (sub_offsets == NULL)
  52             return -1;
  53         memset(sub_offsets, 0, sizeof(regmatch_t) * (n_sub + 1));
  54 
  55         if (regcomp(&crx, rx, REG_EXTENDED)) {
  56             free(sub_offsets);
  57             return -1;
  58         }
  59         r = regexec(&crx, string, n_sub + 1, sub_offsets, 0);
  60         if (r != 0 && r != REG_NOMATCH) {
  61            free(sub_offsets);
  62            return -1;
  63         }
  64         regfree(&crx);
  65         if (r == REG_NOMATCH) {
  66             free(sub_offsets);
  67             return 0;
  68         }
  69 
  70         va_start(va, n_sub);
  71         n = 1;
  72         while (n <= n_sub)
  73         {
  74                 substring = va_arg(va, char**);
  75                 if (substring != NULL)
  76                 {
  77                         if (sub_offsets[n].rm_so == -1) {
  78                             va_end(va);
  79                             free(sub_offsets);
  80                             return - 1;
  81                         }
  82                         *substring = string + sub_offsets[n].rm_so;
  83                         *(string + sub_offsets[n].rm_eo) = 0;
  84                 }
  85                 n++;
  86         }
  87         va_end(va);
  88         free(sub_offsets);
  89         return 1;
  90 }

/*   */