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int open(char *, int, int);
long read(int, unsigned char *, unsigned long);
int printf(char *, ...);
void *malloc(unsigned long);
void exit(int);
void PMurHash32_Process(unsigned int *ph1, unsigned int *pcarry, void *key,
int len) {
unsigned int h1 = *ph1;
unsigned int c = *pcarry;
int n = c & 3;
int i = (4 - n) & 3;
unsigned char *ptr = (unsigned char *)key;
unsigned char *end;
if (i && i <= len) {
do {
int _i = i;
while (_i--) {
c = c >> 8 | *ptr++ << 24;
n++;
len--;
if (n == 4) {
do {
c *= (0xcc9e2d51);
c = (((unsigned int)c << 15) | ((unsigned int)c >> (32 - 15)));
c *= (0x1b873593);
h1 ^= c;
h1 = (((unsigned int)h1 << 13) | ((unsigned int)h1 >> (32 - 13)));
h1 = h1 * 5 + 0xe6546b64;
} while (0);
n = 0;
}
}
} while (0);
}
end = ptr + len / 4 * 4;
for (; ptr < end; ptr += 4) {
unsigned int k1;
k1 = (ptr[0] | ptr[1] << 8 | ptr[2] << 16 | ptr[3] << 24);
do {
k1 *= (0xcc9e2d51);
k1 = (((unsigned int)k1 << 15) | ((unsigned int)k1 >> (32 - 15)));
k1 *= (0x1b873593);
h1 ^= k1;
h1 = (((unsigned int)h1 << 13) | ((unsigned int)h1 >> (32 - 13)));
h1 = h1 * 5 + 0xe6546b64;
} while (0);
}
len -= len / 4 * 4;
do {
int _i = len;
while (_i--) {
c = c >> 8 | *ptr++ << 24;
n++;
len--;
if (n == 4) {
do {
c *= (0xcc9e2d51);
c = (((unsigned int)c << 15) | ((unsigned int)c >> (32 - 15)));
c *= (0x1b873593);
h1 ^= c;
h1 = (((unsigned int)h1 << 13) | ((unsigned int)h1 >> (32 - 13)));
h1 = h1 * 5 + 0xe6546b64;
} while (0);
n = 0;
}
}
} while (0);
*ph1 = h1;
*pcarry = (c & ~0xff) | n;
}
unsigned int PMurHash32_Result(unsigned int h, unsigned int carry,
unsigned int total_length) {
unsigned int k1;
int n = carry & 3;
if (n) {
k1 = carry >> (4 - n) * 8;
k1 *= (0xcc9e2d51);
k1 = (((unsigned int)k1 << 15) | ((unsigned int)k1 >> (32 - 15)));
k1 *= (0x1b873593);
h ^= k1;
}
h ^= total_length;
h ^= h >> 16;
h *= 0x85ebca6b;
h ^= h >> 13;
h *= 0xc2b2ae35;
h ^= h >> 16;
return h;
}
unsigned int PMurHash32(unsigned int seed, void *key, int len) {
unsigned int h1 = seed, carry = 0;
PMurHash32_Process(&h1, &carry, key, len);
return PMurHash32_Result(h1, carry, len);
}
void *read_file(int fd, int *len)
{
int size = 1500 * 1024 * 1024;
unsigned char *arr = malloc(size);
int i;
for (i = 0; ;) {
int rd = read(fd, arr + i, size - i);
if (rd < 0)
exit(2);
if (rd == 0)
break;
i += rd;
}
*len = i;
return arr;
}
int main(int argc, char **argv) {
int fd, len;
char *buf;
fd = open(argv[1], 0, 0);
if (fd == -1)
return 1;
buf = read_file(fd, &len);
printf("len: %d\n", len);
printf("%u\n", PMurHash32(0, buf, len));
return 0;
}
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