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#include "stdafx.h"

#ifdef LOG_ENABLED
extern TCHAR tszLogPath[];

void logA(const char *format, ...)
{
	FILE *out = _tfopen(tszLogPath, _T("a+"));
	if (out) {
		va_list args;
		va_start(args, format);
		vfprintf(out, format, args);
		va_end(args);
		fclose(out);
	}
}
#endif

///////////////////////////////////////////////////////////////////////////////

UINT murmur_hash(const char *str)
{
	size_t len = mir_strlen(str);

	// 'm' and 'r' are mixing constants generated offline.
	// They're not really 'magic', they just happen to work well.
	const unsigned int m = 0x5bd1e995;
	const int r = 24;

	// Initialize the hash to a 'random' value
	unsigned int h = (unsigned)len;

	// Mix 4 bytes at a time into the hash
	const unsigned char *data = (const unsigned char*)str;

	while (len >= 4) {
		unsigned int k = *(unsigned int*)data;

		k *= m;
		k ^= k >> r;
		k *= m;

		h *= m;
		h ^= k;

		data += 4;
		len -= 4;
	}

	// Handle the last few bytes of the input array
	switch(len) {
	case 3: h ^= data[2] << 16;
	case 2: h ^= data[1] << 8;
	case 1: h ^= data[0];
			h *= m;
	}

	// Do a few final mixes of the hash to ensure the last few
	// bytes are well-incorporated.
	h ^= h >> 13;
	h *= m;
	h ^= h >> 15;

	return h;
}