src/common/impl/memrchr.c


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#include "common/memrchr.h"
#include <stddef.h>
#include <stdint.h>

void* memrchr(const void* s, int c, size_t n) {
    if (n == 0) {
        return NULL;
    }

    const uint8_t uc = (uint8_t) c;

    const uint8_t* p = (const uint8_t*) s + n;

    while (n--) {
        if (*--p == uc) {
            return (void*) p;
        }
    }

    return NULL;
}