lib/strutil/replace.c

   1 /*
   2    Functions for replacing substrings in strings.
   3
   4    Copyright (C) 2013
   5    The 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/strutil.h"
  29 #include "lib/strescape.h"
  30
  31 /*** global variables ****************************************************************************/
  32
  33 /*** file scope macro definitions ****************************************************************/
  34
  35 /*** file scope type declarations ****************************************************************/
  36
  37 /*** file scope variables ************************************************************************/
  38
  39 /* --------------------------------------------------------------------------------------------- */
  40 /*** file scope functions ************************************************************************/
  41 /* --------------------------------------------------------------------------------------------- */
  42
  43 static char *
  44 str_ptr_array_join (GPtrArray * str_splints)
  45 {
  46     GString *return_str;
  47     guint i;
  48
  49     return_str = g_string_sized_new (32);
  50     for (i = 0; i < str_splints->len; i++)
  51         g_string_append (return_str, g_ptr_array_index (str_splints, i));
  52
  53     return g_string_free (return_str, FALSE);
  54 }
  55
  56 /* --------------------------------------------------------------------------------------------- */
  57 /*** public functions ****************************************************************************/
  58 /* --------------------------------------------------------------------------------------------- */
  59 /**
  60  * Replace all substrings 'needle' in string 'haystack' by 'replacement'.
  61  * If the 'needle' in the 'haystack' will be escaped by backslash,
  62  * then this occurence isn't be replaced.
  63  *
  64  * @param haystack    string contains substrings for replacement
  65  * @param needle      string for search
  66  * @param replacement string for replace
  67  * @return newly allocated string with replaced substrings
  68  */
  69
  70 char *
  71 str_replace_all (const char *haystack, const char *needle, const char *replacement)
  72 {
  73     size_t needle_len;
  74     GPtrArray *str_splints;
  75     char *return_str;
  76
  77     needle_len = strlen (needle);
  78
  79     str_splints = g_ptr_array_new ();
  80
  81     while (TRUE)
  82     {
  83         char *needle_in_str;
  84
  85         needle_in_str = strstr (haystack, needle);
  86         if (needle_in_str == NULL)
  87         {
  88             if (*haystack != '\0')
  89                 g_ptr_array_add (str_splints, g_strdup (haystack));
  90             break;
  91         }
  92
  93         if (strutils_is_char_escaped (haystack, needle_in_str))
  94         {
  95             char *backslash = needle_in_str - 1;
  96
  97             if (haystack != backslash)
  98                 g_ptr_array_add (str_splints, g_strndup (haystack, backslash - haystack));
  99
 100             g_ptr_array_add (str_splints, g_strndup (backslash + 1, needle_in_str - backslash));
 101             haystack = needle_in_str + 1;
 102             continue;
 103         }
 104         if (needle_in_str - haystack > 0)
 105             g_ptr_array_add (str_splints, g_strndup (haystack, needle_in_str - haystack));
 106         g_ptr_array_add (str_splints, g_strdup (replacement));
 107         haystack = needle_in_str + needle_len;
 108     }
 109     return_str = str_ptr_array_join (str_splints);
 110
 111     g_ptr_array_foreach (str_splints, (GFunc) g_free, NULL);
 112     g_ptr_array_free (str_splints, TRUE);
 113
 114     return return_str;
 115 }
 116
 117 /* --------------------------------------------------------------------------------------------- */