mc/lib/strutil/replace.c

104 lines
3.9 KiB
C

/*
Functions for replacing substrings in strings.
Copyright (C) 2013-2024
Free Software Foundation, Inc.
Written by:
Slava Zanko <slavazanko@gmail.com>, 2013;
This file is part of the Midnight Commander.
The Midnight Commander is free software: you can redistribute it
and/or modify it under the terms of the GNU General Public License as
published by the Free Software Foundation, either version 3 of the License,
or (at your option) any later version.
The Midnight Commander is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <config.h>
#include "lib/global.h"
#include "lib/strutil.h"
/*** global variables ****************************************************************************/
/*** file scope macro definitions ****************************************************************/
/*** file scope type declarations ****************************************************************/
/*** forward declarations (file scope functions) *************************************************/
/*** file scope variables ************************************************************************/
/* --------------------------------------------------------------------------------------------- */
/*** file scope functions ************************************************************************/
/* --------------------------------------------------------------------------------------------- */
/* --------------------------------------------------------------------------------------------- */
/*** public functions ****************************************************************************/
/* --------------------------------------------------------------------------------------------- */
/**
* Replace all substrings 'needle' in string 'haystack' by 'replacement'.
* If the 'needle' in the 'haystack' is escaped by backslash,
* then this occurrence isn't be replaced.
*
* @param haystack string contains substrings for replacement. Cannot be NULL.
* @param needle string for search. Cannot be NULL.
* @param replacement string for replace. Cannot be NULL.
* @return newly allocated string with replaced substrings or NULL if @haystack is empty.
*/
char *
str_replace_all (const char *haystack, const char *needle, const char *replacement)
{
size_t needle_len, replacement_len;
GString *return_str = NULL;
char *needle_in_str;
needle_len = strlen (needle);
replacement_len = strlen (replacement);
while ((needle_in_str = strstr (haystack, needle)) != NULL)
{
if (return_str == NULL)
return_str = g_string_sized_new (32);
if (str_is_char_escaped (haystack, needle_in_str))
{
char *backslash = needle_in_str - 1;
if (haystack != backslash)
g_string_append_len (return_str, haystack, backslash - haystack);
g_string_append_len (return_str, needle_in_str, needle_in_str - backslash);
haystack = needle_in_str + 1;
}
else
{
if (needle_in_str != haystack)
g_string_append_len (return_str, haystack, needle_in_str - haystack);
g_string_append_len (return_str, replacement, replacement_len);
haystack = needle_in_str + needle_len;
}
}
if (*haystack != '\0')
{
if (return_str == NULL)
return strdup (haystack);
g_string_append (return_str, haystack);
}
return (return_str != NULL ? g_string_free (return_str, FALSE) : NULL);
}
/* --------------------------------------------------------------------------------------------- */