/* * The majority of this code was taken from the python-smhasher library, * which can be found here: https://github.com/phensley/python-smhasher * * That library is under the MIT license with the following copyright: * * Copyright (c) 2011 Austin Appleby (Murmur3 routine) * Copyright (c) 2011 Patrick Hensley (Python wrapper, packaging) * Copyright DataStax (Minor modifications to match Cassandra's MM3 hashes) * */ #define PY_SSIZE_T_CLEAN 1 #include #include #if PY_VERSION_HEX < 0x02050000 typedef int Py_ssize_t; #define PY_SSIZE_T_MAX INT_MAX #define PY_SSIZE_T_MIN INT_MIN #endif #ifdef PYPY_VERSION #define COMPILING_IN_PYPY 1 #define COMPILING_IN_CPYTHON 0 #else #define COMPILING_IN_PYPY 0 #define COMPILING_IN_CPYTHON 1 #endif //----------------------------------------------------------------------------- // Platform-specific functions and macros // Microsoft Visual Studio #if defined(_MSC_VER) typedef unsigned char uint8_t; typedef unsigned long uint32_t; typedef unsigned __int64 uint64_t; typedef char int8_t; typedef long int32_t; typedef __int64 int64_t; #define FORCE_INLINE __forceinline #include #define ROTL32(x,y) _rotl(x,y) #define ROTL64(x,y) _rotl64(x,y) #define BIG_CONSTANT(x) (x) // Other compilers #else // defined(_MSC_VER) #include #define FORCE_INLINE inline __attribute__((always_inline)) inline uint32_t rotl32 ( int32_t x, int8_t r ) { // cast to unsigned for logical right bitshift (to match C* MM3 implementation) return (x << r) | ((int32_t) (((uint32_t) x) >> (32 - r))); } inline int64_t rotl64 ( int64_t x, int8_t r ) { // cast to unsigned for logical right bitshift (to match C* MM3 implementation) return (x << r) | ((int64_t) (((uint64_t) x) >> (64 - r))); } #define ROTL32(x,y) rotl32(x,y) #define ROTL64(x,y) rotl64(x,y) #define BIG_CONSTANT(x) (x##LL) #endif // !defined(_MSC_VER) //----------------------------------------------------------------------------- // Block read - if your platform needs to do endian-swapping or can only // handle aligned reads, do the conversion here // TODO 32bit? FORCE_INLINE int64_t getblock ( const int64_t * p, int i ) { return p[i]; } //----------------------------------------------------------------------------- // Finalization mix - force all bits of a hash block to avalanche FORCE_INLINE int64_t fmix ( int64_t k ) { // cast to unsigned for logical right bitshift (to match C* MM3 implementation) k ^= ((uint64_t) k) >> 33; k *= BIG_CONSTANT(0xff51afd7ed558ccd); k ^= ((uint64_t) k) >> 33; k *= BIG_CONSTANT(0xc4ceb9fe1a85ec53); k ^= ((uint64_t) k) >> 33; return k; } int64_t MurmurHash3_x64_128 (const void * key, const int len, const uint32_t seed) { const int8_t * data = (const int8_t*)key; const int nblocks = len / 16; int64_t h1 = seed; int64_t h2 = seed; int64_t c1 = BIG_CONSTANT(0x87c37b91114253d5); int64_t c2 = BIG_CONSTANT(0x4cf5ad432745937f); int64_t k1 = 0; int64_t k2 = 0; const int64_t * blocks = (const int64_t *)(data); const int8_t * tail = (const int8_t*)(data + nblocks*16); //---------- // body int i; for(i = 0; i < nblocks; i++) { int64_t k1 = getblock(blocks,i*2+0); int64_t k2 = getblock(blocks,i*2+1); k1 *= c1; k1 = ROTL64(k1,31); k1 *= c2; h1 ^= k1; h1 = ROTL64(h1,27); h1 += h2; h1 = h1*5+0x52dce729; k2 *= c2; k2 = ROTL64(k2,33); k2 *= c1; h2 ^= k2; h2 = ROTL64(h2,31); h2 += h1; h2 = h2*5+0x38495ab5; } //---------- // tail switch(len & 15) { case 15: k2 ^= ((int64_t) (tail[14])) << 48; case 14: k2 ^= ((int64_t) (tail[13])) << 40; case 13: k2 ^= ((int64_t) (tail[12])) << 32; case 12: k2 ^= ((int64_t) (tail[11])) << 24; case 11: k2 ^= ((int64_t) (tail[10])) << 16; case 10: k2 ^= ((int64_t) (tail[ 9])) << 8; case 9: k2 ^= ((int64_t) (tail[ 8])) << 0; k2 *= c2; k2 = ROTL64(k2,33); k2 *= c1; h2 ^= k2; case 8: k1 ^= ((int64_t) (tail[ 7])) << 56; case 7: k1 ^= ((int64_t) (tail[ 6])) << 48; case 6: k1 ^= ((int64_t) (tail[ 5])) << 40; case 5: k1 ^= ((int64_t) (tail[ 4])) << 32; case 4: k1 ^= ((int64_t) (tail[ 3])) << 24; case 3: k1 ^= ((int64_t) (tail[ 2])) << 16; case 2: k1 ^= ((int64_t) (tail[ 1])) << 8; case 1: k1 ^= ((int64_t) (tail[ 0])) << 0; k1 *= c1; k1 = ROTL64(k1,31); k1 *= c2; h1 ^= k1; }; //---------- // finalization h1 ^= len; h2 ^= len; h1 += h2; h2 += h1; h1 = fmix(h1); h2 = fmix(h2); h1 += h2; h2 += h1; return h1; } struct module_state { PyObject *error; }; // pypy3 doesn't have GetState yet. #if COMPILING_IN_CPYTHON && PY_MAJOR_VERSION >= 3 #define GETSTATE(m) ((struct module_state*)PyModule_GetState(m)) #else #define GETSTATE(m) (&_state) static struct module_state _state; #endif static PyObject * murmur3(PyObject *self, PyObject *args) { const char *key; Py_ssize_t len; uint32_t seed = 0; int64_t result = 0; if (!PyArg_ParseTuple(args, "s#|I", &key, &len, &seed)) { return NULL; } // TODO handle x86 version? result = MurmurHash3_x64_128((void *)key, len, seed); return (PyObject *) PyLong_FromLongLong(result); } static PyMethodDef cmurmur3_methods[] = { {"murmur3", murmur3, METH_VARARGS, "Make an x64 murmur3 64-bit hash value"}, {NULL, NULL, 0, NULL} }; #if PY_MAJOR_VERSION >= 3 static int cmurmur3_traverse(PyObject *m, visitproc visit, void *arg) { Py_VISIT(GETSTATE(m)->error); return 0; } static int cmurmur3_clear(PyObject *m) { Py_CLEAR(GETSTATE(m)->error); return 0; } static struct PyModuleDef moduledef = { PyModuleDef_HEAD_INIT, "cmurmur3", NULL, sizeof(struct module_state), cmurmur3_methods, NULL, cmurmur3_traverse, cmurmur3_clear, NULL }; #define INITERROR return NULL PyObject * PyInit_cmurmur3(void) #else #define INITERROR return void initcmurmur3(void) #endif { #if PY_MAJOR_VERSION >= 3 PyObject *module = PyModule_Create(&moduledef); #else PyObject *module = Py_InitModule("cmurmur3", cmurmur3_methods); #endif struct module_state *st = NULL; if (module == NULL) INITERROR; st = GETSTATE(module); st->error = PyErr_NewException("cmurmur3.Error", NULL, NULL); if (st->error == NULL) { Py_DECREF(module); INITERROR; } #if PY_MAJOR_VERSION >= 3 return module; #endif }