lib/strutil/replace.c

   1 /*
   2    Functions for replacing substrings in strings.
   3
   4    Copyright (C) 2013-2016
   5    Free Software Foundation, Inc.
   6
   7    Written by:
   8    Slava Zanko <slavazanko@gmail.com>, 2013;
   9
  10    This file is part of the Midnight Commander.
  11
  12    The Midnight Commander is free software: you can redistribute it
  13    and/or modify it under the terms of the GNU General Public License as
  14    published by the Free Software Foundation, either version 3 of the License,
  15    or (at your option) any later version.
  16
  17    The Midnight Commander is distributed in the hope that it will be useful,
  18    but WITHOUT ANY WARRANTY; without even the implied warranty of
  19    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20    GNU General Public License for more details.
  21
  22    You should have received a copy of the GNU General Public License
  23    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  24  */
  25
  26 #include <config.h>
  27
  28 #include "lib/global.h"
  29 #include "lib/strescape.h"
  30 #include "lib/strutil.h"
  31
  32 /*** global variables ****************************************************************************/
  33
  34 /*** file scope macro definitions ****************************************************************/
  35
  36 /*** file scope type declarations ****************************************************************/
  37
  38 /*** file scope variables ************************************************************************/
  39
  40 /* --------------------------------------------------------------------------------------------- */
  41 /*** file scope functions ************************************************************************/
  42 /* --------------------------------------------------------------------------------------------- */
  43
  44 static char *
  45 str_ptr_array_join (GPtrArray * str_splints)
  46 {
  47     GString *return_str;
  48     guint i;
  49
  50     return_str = g_string_sized_new (32);
  51     for (i = 0; i < str_splints->len; i++)
  52         g_string_append (return_str, g_ptr_array_index (str_splints, i));
  53
  54     return g_string_free (return_str, FALSE);
  55 }
  56
  57 /* --------------------------------------------------------------------------------------------- */
  58 /*** public functions ****************************************************************************/
  59 /* --------------------------------------------------------------------------------------------- */
  60 /**
  61  * Replace all substrings 'needle' in string 'haystack' by 'replacement'.
  62  * If the 'needle' in the 'haystack' will be escaped by backslash,
  63  * then this occurrence isn't be replaced.
  64  *
  65  * @param haystack    string contains substrings for replacement
  66  * @param needle      string for search
  67  * @param replacement string for replace
  68  * @return newly allocated string with replaced substrings
  69  */
  70
  71 char *
  72 str_replace_all (const char *haystack, const char *needle, const char *replacement)
  73 {
  74     size_t needle_len;
  75     GPtrArray *str_splints;
  76     char *return_str;
  77
  78     needle_len = strlen (needle);
  79
  80     str_splints = g_ptr_array_new ();
  81
  82     while (TRUE)
  83     {
  84         char *needle_in_str;
  85
  86         needle_in_str = strstr (haystack, needle);
  87         if (needle_in_str == NULL)
  88         {
  89             if (*haystack != '\0')
  90                 g_ptr_array_add (str_splints, g_strdup (haystack));
  91             break;
  92         }
  93
  94         if (strutils_is_char_escaped (haystack, needle_in_str))
  95         {
  96             char *backslash = needle_in_str - 1;
  97
  98             if (haystack != backslash)
  99                 g_ptr_array_add (str_splints, g_strndup (haystack, backslash - haystack));
 100
 101             g_ptr_array_add (str_splints, g_strndup (backslash + 1, needle_in_str - backslash));
 102             haystack = needle_in_str + 1;
 103             continue;
 104         }
 105         if (needle_in_str - haystack > 0)
 106             g_ptr_array_add (str_splints, g_strndup (haystack, needle_in_str - haystack));
 107         g_ptr_array_add (str_splints, g_strdup (replacement));
 108         haystack = needle_in_str + needle_len;
 109     }
 110     return_str = str_ptr_array_join (str_splints);
 111
 112     g_ptr_array_foreach (str_splints, (GFunc) g_free, NULL);
 113     g_ptr_array_free (str_splints, TRUE);
 114
 115     return return_str;
 116 }
 117
 118 /* --------------------------------------------------------------------------------------------- */