Function GenerateSoundEntryHash

extensions/sdktools/vsound.cpp:273–317

#define SOUND_ENTRY_HASH_SEED 0x444F5441

uint32 GenerateSoundEntryHash(char const *pSoundEntry)
{
	// First we need to convert the sound entry to lowercase before we calculate the hash
	int nSoundEntryLength = strlen(pSoundEntry);
	char *pSoundEntryLowerCase = (char *)stackalloc(nSoundEntryLength + 1);

	for (int nIndex = 0; nIndex < nSoundEntryLength; nIndex++)
		pSoundEntryLowerCase[nIndex] = tolower(pSoundEntry[nIndex]);

	// Second we need to calculate the hash using the algorithm reconstructed from CS:GO
	const uint32 nMagicNumber = 0x5bd1e995;

	uint32 nSoundHash = SOUND_ENTRY_HASH_SEED ^ nSoundEntryLength;

	unsigned char *pData = (unsigned char *)pSoundEntryLowerCase;

	while (nSoundEntryLength >= 4)
	{
		uint32 nLittleDWord = LittleDWord(*(uint32 *)pData);

		nLittleDWord *= nMagicNumber;
		nLittleDWord ^= nLittleDWord >> 24;
		nLittleDWord *= nMagicNumber;

		nSoundHash *= nMagicNumber;
		nSoundHash ^= nLittleDWord;

		pData += 4;
		nSoundEntryLength -= 4;
	}

	switch (nSoundEntryLength)
	{
		case 3: nSoundHash ^= pData[2] << 16;
		case 2: nSoundHash ^= pData[1] << 8;
		case 1: nSoundHash ^= pData[0];
			nSoundHash *= nMagicNumber;
	};

	nSoundHash ^= nSoundHash >> 13;
	nSoundHash *= nMagicNumber;
	nSoundHash ^= nSoundHash >> 15;

	return nSoundHash;
}
#endif

#if SOURCE_ENGINE == SE_CSGO || SOURCE_ENGINE == SE_BLADE || SOURCE_ENGINE == SE_MCV