annotate contrib/python-zstandard/c-ext/constants.c @ 46374:e92ca942ddca

cext: add Python 3.10 support

* Replace "Py_TYPE(obj) = type;" with "Py_SET_TYPE(obj, type);"
* Add pythoncapi_compat.h header file to get Py_SET_TYPE() on Python
  2.7-3.8. Header file added to mercurial/ and
  contrib/python-zstandard/zstd/common/.

In Python 3.10, Py_TYPE(obj) must not longer be used as an l-value.

pythoncapi_compat.h comes from:
https://github.com/pythoncapi/pythoncapi_compat

Differential Revision: https://phab.mercurial-scm.org/D9825

/**
* 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.
*/

#include "python-zstandard.h"

extern PyObject* ZstdError;

static char frame_header[] = {
	'\x28',
	'\xb5',
	'\x2f',
	'\xfd',
};

void constants_module_init(PyObject* mod) {
	PyObject* version;
	PyObject* zstdVersion;
	PyObject* frameHeader;

#if PY_MAJOR_VERSION >= 3
	version = PyUnicode_FromString(PYTHON_ZSTANDARD_VERSION);
#else
	version = PyString_FromString(PYTHON_ZSTANDARD_VERSION);
#endif
	PyModule_AddObject(mod, "__version__", version);

	ZstdError = PyErr_NewException("zstd.ZstdError", NULL, NULL);
	PyModule_AddObject(mod, "ZstdError", ZstdError);

	PyModule_AddIntConstant(mod, "FLUSH_BLOCK", 0);
	PyModule_AddIntConstant(mod, "FLUSH_FRAME", 1);

	PyModule_AddIntConstant(mod, "COMPRESSOBJ_FLUSH_FINISH", compressorobj_flush_finish);
	PyModule_AddIntConstant(mod, "COMPRESSOBJ_FLUSH_BLOCK", compressorobj_flush_block);

	/* For now, the version is a simple tuple instead of a dedicated type. */
	zstdVersion = PyTuple_New(3);
	PyTuple_SetItem(zstdVersion, 0, PyLong_FromLong(ZSTD_VERSION_MAJOR));
	PyTuple_SetItem(zstdVersion, 1, PyLong_FromLong(ZSTD_VERSION_MINOR));
	PyTuple_SetItem(zstdVersion, 2, PyLong_FromLong(ZSTD_VERSION_RELEASE));
	PyModule_AddObject(mod, "ZSTD_VERSION", zstdVersion);

	frameHeader = PyBytes_FromStringAndSize(frame_header, sizeof(frame_header));
	if (frameHeader) {
		PyModule_AddObject(mod, "FRAME_HEADER", frameHeader);
	}
	else {
		PyErr_Format(PyExc_ValueError, "could not create frame header object");
	}

	PyModule_AddObject(mod, "CONTENTSIZE_UNKNOWN",
		PyLong_FromUnsignedLongLong(ZSTD_CONTENTSIZE_UNKNOWN));
	PyModule_AddObject(mod, "CONTENTSIZE_ERROR",
		PyLong_FromUnsignedLongLong(ZSTD_CONTENTSIZE_ERROR));

	PyModule_AddIntConstant(mod, "MAX_COMPRESSION_LEVEL", ZSTD_maxCLevel());
	PyModule_AddIntConstant(mod, "COMPRESSION_RECOMMENDED_INPUT_SIZE",
		(long)ZSTD_CStreamInSize());
	PyModule_AddIntConstant(mod, "COMPRESSION_RECOMMENDED_OUTPUT_SIZE",
		(long)ZSTD_CStreamOutSize());
	PyModule_AddIntConstant(mod, "DECOMPRESSION_RECOMMENDED_INPUT_SIZE",
		(long)ZSTD_DStreamInSize());
	PyModule_AddIntConstant(mod, "DECOMPRESSION_RECOMMENDED_OUTPUT_SIZE",
		(long)ZSTD_DStreamOutSize());

	PyModule_AddIntConstant(mod, "MAGIC_NUMBER", ZSTD_MAGICNUMBER);
	PyModule_AddIntConstant(mod, "BLOCKSIZELOG_MAX", ZSTD_BLOCKSIZELOG_MAX);
	PyModule_AddIntConstant(mod, "BLOCKSIZE_MAX", ZSTD_BLOCKSIZE_MAX);
	PyModule_AddIntConstant(mod, "WINDOWLOG_MIN", ZSTD_WINDOWLOG_MIN);
	PyModule_AddIntConstant(mod, "WINDOWLOG_MAX", ZSTD_WINDOWLOG_MAX);
	PyModule_AddIntConstant(mod, "CHAINLOG_MIN", ZSTD_CHAINLOG_MIN);
	PyModule_AddIntConstant(mod, "CHAINLOG_MAX", ZSTD_CHAINLOG_MAX);
	PyModule_AddIntConstant(mod, "HASHLOG_MIN", ZSTD_HASHLOG_MIN);
	PyModule_AddIntConstant(mod, "HASHLOG_MAX", ZSTD_HASHLOG_MAX);
	PyModule_AddIntConstant(mod, "HASHLOG3_MAX", ZSTD_HASHLOG3_MAX);
	PyModule_AddIntConstant(mod, "SEARCHLOG_MIN", ZSTD_SEARCHLOG_MIN);
	PyModule_AddIntConstant(mod, "SEARCHLOG_MAX", ZSTD_SEARCHLOG_MAX);
	PyModule_AddIntConstant(mod, "MINMATCH_MIN", ZSTD_MINMATCH_MIN);
	PyModule_AddIntConstant(mod, "MINMATCH_MAX", ZSTD_MINMATCH_MAX);
	/* TODO SEARCHLENGTH_* is deprecated. */
	PyModule_AddIntConstant(mod, "SEARCHLENGTH_MIN", ZSTD_MINMATCH_MIN);
	PyModule_AddIntConstant(mod, "SEARCHLENGTH_MAX", ZSTD_MINMATCH_MAX);
	PyModule_AddIntConstant(mod, "TARGETLENGTH_MIN", ZSTD_TARGETLENGTH_MIN);
	PyModule_AddIntConstant(mod, "TARGETLENGTH_MAX", ZSTD_TARGETLENGTH_MAX);
	PyModule_AddIntConstant(mod, "LDM_MINMATCH_MIN", ZSTD_LDM_MINMATCH_MIN);
	PyModule_AddIntConstant(mod, "LDM_MINMATCH_MAX", ZSTD_LDM_MINMATCH_MAX);
	PyModule_AddIntConstant(mod, "LDM_BUCKETSIZELOG_MAX", ZSTD_LDM_BUCKETSIZELOG_MAX);

	PyModule_AddIntConstant(mod, "STRATEGY_FAST", ZSTD_fast);
	PyModule_AddIntConstant(mod, "STRATEGY_DFAST", ZSTD_dfast);
	PyModule_AddIntConstant(mod, "STRATEGY_GREEDY", ZSTD_greedy);
	PyModule_AddIntConstant(mod, "STRATEGY_LAZY", ZSTD_lazy);
	PyModule_AddIntConstant(mod, "STRATEGY_LAZY2", ZSTD_lazy2);
	PyModule_AddIntConstant(mod, "STRATEGY_BTLAZY2", ZSTD_btlazy2);
	PyModule_AddIntConstant(mod, "STRATEGY_BTOPT", ZSTD_btopt);
	PyModule_AddIntConstant(mod, "STRATEGY_BTULTRA", ZSTD_btultra);
	PyModule_AddIntConstant(mod, "STRATEGY_BTULTRA2", ZSTD_btultra2);

	PyModule_AddIntConstant(mod, "DICT_TYPE_AUTO", ZSTD_dct_auto);
	PyModule_AddIntConstant(mod, "DICT_TYPE_RAWCONTENT", ZSTD_dct_rawContent);
	PyModule_AddIntConstant(mod, "DICT_TYPE_FULLDICT", ZSTD_dct_fullDict);

	PyModule_AddIntConstant(mod, "FORMAT_ZSTD1", ZSTD_f_zstd1);
	PyModule_AddIntConstant(mod, "FORMAT_ZSTD1_MAGICLESS", ZSTD_f_zstd1_magicless);
}