gpsp/libretro/libretro-common/compat/compat_strcasestr.c

59 lines
2.1 KiB
C

/* Copyright (C) 2010-2020 The RetroArch team
*
* ---------------------------------------------------------------------------------------
* The following license statement only applies to this file (compat_strcasestr.c).
* ---------------------------------------------------------------------------------------
*
* Permission is hereby granted, free of charge,
* to any person obtaining a copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software,
* and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include <ctype.h>
#include <compat/strcasestr.h>
/* Pretty much strncasecmp. */
static int casencmp(const char *a, const char *b, size_t n)
{
size_t i;
for (i = 0; i < n; i++)
{
int a_lower = tolower(a[i]);
int b_lower = tolower(b[i]);
if (a_lower != b_lower)
return a_lower - b_lower;
}
return 0;
}
char *strcasestr_retro__(const char *haystack, const char *needle)
{
size_t i, search_off;
size_t hay_len = strlen(haystack);
size_t needle_len = strlen(needle);
if (needle_len > hay_len)
return NULL;
search_off = hay_len - needle_len;
for (i = 0; i <= search_off; i++)
if (!casencmp(haystack + i, needle, needle_len))
return (char*)haystack + i;
return NULL;
}