32 lines
752 B
32 lines
752 B
#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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