44 lines
1.4 KiB
C
44 lines
1.4 KiB
C
/*
|
|
* Copyright (c) 2013 Jonas 'Sortie' Termansen.
|
|
*
|
|
* Permission to use, copy, modify, and distribute this software for any
|
|
* purpose with or without fee is hereby granted, provided that the above
|
|
* copyright notice and this permission notice appear in all copies.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
|
|
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
|
|
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
|
|
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
|
|
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
|
|
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
|
|
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
|
|
*
|
|
* wchar/wcsstr.c
|
|
* Locate a wide substring.
|
|
*/
|
|
|
|
#include <stdbool.h>
|
|
#include <wchar.h>
|
|
|
|
// TODO: This simple and hacky implementation runs in O(N^2) even though this
|
|
// problem can be solved in O(N).
|
|
wchar_t* wcsstr(const wchar_t* restrict haystack,
|
|
const wchar_t* restrict needle)
|
|
{
|
|
if ( !needle[0] )
|
|
return (wchar_t*) haystack;
|
|
for ( size_t i = 0; haystack[i]; i++ )
|
|
{
|
|
bool diff = false;
|
|
for ( size_t j = 0; needle[j]; j++ )
|
|
{
|
|
if ( (diff = haystack[i+j] != needle[j]) )
|
|
break;
|
|
}
|
|
if ( diff )
|
|
continue;
|
|
return (wchar_t*) haystack + i;
|
|
}
|
|
return NULL;
|
|
}
|