32 lines
752 B
C
32 lines
752 B
C
#include "../git-compat-util.h"
|
|
|
|
void *gitmemmem(const void *haystack, size_t haystack_len,
|
|
const void *needle, size_t needle_len)
|
|
{
|
|
const char *begin = haystack;
|
|
const char *last_possible = begin + haystack_len - needle_len;
|
|
const char *tail = needle;
|
|
char point;
|
|
|
|
/*
|
|
* The first occurrence of the empty string is deemed to occur at
|
|
* the beginning of the string.
|
|
*/
|
|
if (needle_len == 0)
|
|
return (void *)begin;
|
|
|
|
/*
|
|
* Sanity check, otherwise the loop might search through the whole
|
|
* memory.
|
|
*/
|
|
if (haystack_len < needle_len)
|
|
return NULL;
|
|
|
|
point = *tail++;
|
|
for (; begin <= last_possible; begin++) {
|
|
if (*begin == point && !memcmp(begin + 1, tail, needle_len - 1))
|
|
return (void *)begin;
|
|
}
|
|
|
|
return NULL;
|
|
}
|