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