openstack/deb-python-cassandra-driver
Code Issues Proposed changes

Add missing cmurmur3.c, update .gitignore

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This commit is contained in:
Adam Holmberg
2015-08-05 17:30:59 -05:00
parent d97562d506
commit bb788957f0
2 changed files with 276 additions and 1 deletions
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2
.gitignore vendored
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@@ -18,7 +18,7 @@ setuptools*.tar.gz
setuptools*.egg
cassandra/*.c
!cassandra/murmur3.c
!cassandra/cmurmur3.c
# OSX
.DS_Store

275
cassandra/cmurmur3.c Normal file
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@@ -0,0 +1,275 @@
/*
* 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 2013 DataStax (Minor modifications to match Cassandra's MM3 hashes)
*
*/
#define PY_SSIZE_T_CLEAN 1
#include <Python.h>
#include <stdio.h>
#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 <stdlib.h>
#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 <stdint.h>
#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
}