com32/lib/strreplace.c

   1 /* ----------------------------------------------------------------------- *
   2  *
   3  *   Copyright 2011 Erwan Velu - All Rights Reserved
   4  *
   5  *   Permission is hereby granted, free of charge, to any person
   6  *   obtaining a copy of this software and associated documentation
   7  *   files (the "Software"), to deal in the Software without
   8  *   restriction, including without limitation the rights to use,
   9  *   copy, modify, merge, publish, distribute, sublicense, and/or
  10  *   sell copies of the Software, and to permit persons to whom
  11  *   the Software is furnished to do so, subject to the following
  12  *   conditions:
  13  *
  14  *   The above copyright notice and this permission notice shall
  15  *   be included in all copies or substantial portions of the Software.
  16  *
  17  *   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  18  *   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
  19  *   OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  20  *   NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  21  *   HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  22  *   WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  23  *   FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  24  *   OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  * -----------------------------------------------------------------------
  27  */
  28
  29 #include <string.h>
  30 #include <stdlib.h>
  31
  32 char *strreplace(const char *string, const char *string_to_replace,
  33                  const char *string_to_insert)
  34 {
  35     char *token = NULL;
  36     char *out = NULL;
  37
  38     size_t slen, srlen, silen;
  39
  40     token = strstr(string, string_to_replace);
  41     if (!token)
  42         return strdup(string);
  43
  44     slen  = strlen(string);
  45     srlen = strlen(string_to_replace);
  46     silen = strlen(string_to_insert);
  47
  48     out = malloc(slen - srlen + silen + 1);
  49     if (!out)
  50         return NULL;
  51
  52     memcpy(out, string, token - string);
  53     memcpy(out + (token - string), string_to_insert, silen);
  54     memcpy(out + (token - string) + silen, token + srlen,
  55            slen - srlen - (token - string) + 1);
  56
  57     return out;
  58 }