Mercurial > hg
view contrib/python-zstandard/zstd.c @ 34648:4889b84b15f2
check-code: suggest pycompat.is(posix|windows|darwin)
Differential Revision: https://phab.mercurial-scm.org/D1037
author | Jun Wu <quark@fb.com> |
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date | Thu, 12 Oct 2017 09:34:58 -0700 |
parents | 39d36c2db68e |
children | b1fb341d8a61 |
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/** * Copyright (c) 2016-present, Gregory Szorc * All rights reserved. * * This software may be modified and distributed under the terms * of the BSD license. See the LICENSE file for details. */ /* A Python C extension for Zstandard. */ #if defined(_WIN32) #define WIN32_LEAN_AND_MEAN #include <Windows.h> #elif defined(__APPLE__) || defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__NetBSD__) || defined(__DragonFly__) #include <sys/types.h> #include <sys/sysctl.h> #endif #include "python-zstandard.h" PyObject *ZstdError; PyDoc_STRVAR(estimate_compression_context_size__doc__, "estimate_compression_context_size(compression_parameters)\n" "\n" "Give the amount of memory allocated for a compression context given a\n" "CompressionParameters instance"); PyDoc_STRVAR(estimate_decompression_context_size__doc__, "estimate_decompression_context_size()\n" "\n" "Estimate the amount of memory allocated to a decompression context.\n" ); static PyObject* estimate_decompression_context_size(PyObject* self) { return PyLong_FromSize_t(ZSTD_estimateDCtxSize()); } PyDoc_STRVAR(get_compression_parameters__doc__, "get_compression_parameters(compression_level[, source_size[, dict_size]])\n" "\n" "Obtains a ``CompressionParameters`` instance from a compression level and\n" "optional input size and dictionary size"); PyDoc_STRVAR(get_frame_parameters__doc__, "get_frame_parameters(data)\n" "\n" "Obtains a ``FrameParameters`` instance by parsing data.\n"); PyDoc_STRVAR(train_dictionary__doc__, "train_dictionary(dict_size, samples)\n" "\n" "Train a dictionary from sample data.\n" "\n" "A compression dictionary of size ``dict_size`` will be created from the\n" "iterable of samples provided by ``samples``.\n" "\n" "The raw dictionary content will be returned\n"); PyDoc_STRVAR(train_cover_dictionary__doc__, "train_cover_dictionary(dict_size, samples, k=None, d=None, notifications=0, dict_id=0, level=0)\n" "\n" "Train a dictionary from sample data using the COVER algorithm.\n" "\n" "This behaves like ``train_dictionary()`` except a different algorithm is\n" "used to create the dictionary. The algorithm has 2 parameters: ``k`` and\n" "``d``. These control the *segment size* and *dmer size*. A reasonable range\n" "for ``k`` is ``[16, 2048+]``. A reasonable range for ``d`` is ``[6, 16]``.\n" "``d`` must be less than or equal to ``k``.\n" ); static char zstd_doc[] = "Interface to zstandard"; static PyMethodDef zstd_methods[] = { /* TODO remove since it is a method on CompressionParameters. */ { "estimate_compression_context_size", (PyCFunction)estimate_compression_context_size, METH_VARARGS, estimate_compression_context_size__doc__ }, { "estimate_decompression_context_size", (PyCFunction)estimate_decompression_context_size, METH_NOARGS, estimate_decompression_context_size__doc__ }, { "get_compression_parameters", (PyCFunction)get_compression_parameters, METH_VARARGS, get_compression_parameters__doc__ }, { "get_frame_parameters", (PyCFunction)get_frame_parameters, METH_VARARGS, get_frame_parameters__doc__ }, { "train_dictionary", (PyCFunction)train_dictionary, METH_VARARGS | METH_KEYWORDS, train_dictionary__doc__ }, { "train_cover_dictionary", (PyCFunction)train_cover_dictionary, METH_VARARGS | METH_KEYWORDS, train_cover_dictionary__doc__ }, { NULL, NULL } }; void bufferutil_module_init(PyObject* mod); void compressobj_module_init(PyObject* mod); void compressor_module_init(PyObject* mod); void compressionparams_module_init(PyObject* mod); void constants_module_init(PyObject* mod); void compressiondict_module_init(PyObject* mod); void compressionwriter_module_init(PyObject* mod); void compressoriterator_module_init(PyObject* mod); void decompressor_module_init(PyObject* mod); void decompressobj_module_init(PyObject* mod); void decompressionwriter_module_init(PyObject* mod); void decompressoriterator_module_init(PyObject* mod); void frameparams_module_init(PyObject* mod); void zstd_module_init(PyObject* m) { /* python-zstandard relies on unstable zstd C API features. This means that changes in zstd may break expectations in python-zstandard. python-zstandard is distributed with a copy of the zstd sources. python-zstandard is only guaranteed to work with the bundled version of zstd. However, downstream redistributors or packagers may unbundle zstd from python-zstandard. This can result in a mismatch between zstd versions and API semantics. This essentially "voids the warranty" of python-zstandard and may cause undefined behavior. We detect this mismatch here and refuse to load the module if this scenario is detected. */ if (ZSTD_VERSION_NUMBER != 10103 || ZSTD_versionNumber() != 10103) { PyErr_SetString(PyExc_ImportError, "zstd C API mismatch; Python bindings not compiled against expected zstd version"); return; } bufferutil_module_init(m); compressionparams_module_init(m); compressiondict_module_init(m); compressobj_module_init(m); compressor_module_init(m); compressionwriter_module_init(m); compressoriterator_module_init(m); constants_module_init(m); decompressor_module_init(m); decompressobj_module_init(m); decompressionwriter_module_init(m); decompressoriterator_module_init(m); frameparams_module_init(m); } #if PY_MAJOR_VERSION >= 3 static struct PyModuleDef zstd_module = { PyModuleDef_HEAD_INIT, "zstd", zstd_doc, -1, zstd_methods }; PyMODINIT_FUNC PyInit_zstd(void) { PyObject *m = PyModule_Create(&zstd_module); if (m) { zstd_module_init(m); if (PyErr_Occurred()) { Py_DECREF(m); m = NULL; } } return m; } #else PyMODINIT_FUNC initzstd(void) { PyObject *m = Py_InitModule3("zstd", zstd_methods, zstd_doc); if (m) { zstd_module_init(m); } } #endif /* Attempt to resolve the number of CPUs in the system. */ int cpu_count() { int count = 0; #if defined(_WIN32) SYSTEM_INFO si; si.dwNumberOfProcessors = 0; GetSystemInfo(&si); count = si.dwNumberOfProcessors; #elif defined(__APPLE__) int num; size_t size = sizeof(int); if (0 == sysctlbyname("hw.logicalcpu", &num, &size, NULL, 0)) { count = num; } #elif defined(__linux__) count = sysconf(_SC_NPROCESSORS_ONLN); #elif defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__NetBSD__) || defined(__DragonFly__) int mib[2]; size_t len = sizeof(count); mib[0] = CTL_HW; mib[1] = HW_NCPU; if (0 != sysctl(mib, 2, &count, &len, NULL, 0)) { count = 0; } #elif defined(__hpux) count = mpctl(MPC_GETNUMSPUS, NULL, NULL); #endif return count; } size_t roundpow2(size_t i) { i--; i |= i >> 1; i |= i >> 2; i |= i >> 4; i |= i >> 8; i |= i >> 16; i++; return i; }