1#include <stdint.h> 2#include <string.h> 3 4static inline uint32_t swapc(uint32_t x, int c) { 5 return c ? x >> 24 | (x >> 8 & 0xff00) | (x << 8 & 0xff0000) | x << 24 : x; 6} 7 8const char* __mo_lookup(const void* p, size_t size, const char* s) { 9 const uint32_t* mo = p; 10 int sw = *mo - 0x950412de; 11 uint32_t b = 0, n = swapc(mo[2], sw); 12 uint32_t o = swapc(mo[3], sw); 13 uint32_t t = swapc(mo[4], sw); 14 if (n >= size / 4 || o >= size - 4 * n || t >= size - 4 * n || ((o | t) % 4)) 15 return 0; 16 o /= 4; 17 t /= 4; 18 for (;;) { 19 uint32_t ol = swapc(mo[o + 2 * (b + n / 2)], sw); 20 uint32_t os = swapc(mo[o + 2 * (b + n / 2) + 1], sw); 21 if (os >= size || ol >= size - os || ((char*)p)[os + ol]) 22 return 0; 23 int sign = strcmp(s, (char*)p + os); 24 if (!sign) { 25 uint32_t tl = swapc(mo[t + 2 * (b + n / 2)], sw); 26 uint32_t ts = swapc(mo[t + 2 * (b + n / 2) + 1], sw); 27 if (ts >= size || tl >= size - ts || ((char*)p)[ts + tl]) 28 return 0; 29 return (char*)p + ts; 30 } else if (n == 1) 31 return 0; 32 else if (sign < 0) 33 n /= 2; 34 else { 35 b += n / 2; 36 n -= n / 2; 37 } 38 } 39 return 0; 40} 41