contrib/python-zstandard/c-ext/compressionparams.c
changeset 30435 b86a448a2965
child 30498 d7a05d8351d0
equal deleted inserted replaced
30434:2e484bdea8c4 30435:b86a448a2965
       
     1 /**
       
     2 * Copyright (c) 2016-present, Gregory Szorc
       
     3 * All rights reserved.
       
     4 *
       
     5 * This software may be modified and distributed under the terms
       
     6 * of the BSD license. See the LICENSE file for details.
       
     7 */
       
     8 
       
     9 #include "python-zstandard.h"
       
    10 
       
    11 void ztopy_compression_parameters(CompressionParametersObject* params, ZSTD_compressionParameters* zparams) {
       
    12 	zparams->windowLog = params->windowLog;
       
    13 	zparams->chainLog = params->chainLog;
       
    14 	zparams->hashLog = params->hashLog;
       
    15 	zparams->searchLog = params->searchLog;
       
    16 	zparams->searchLength = params->searchLength;
       
    17 	zparams->targetLength = params->targetLength;
       
    18 	zparams->strategy = params->strategy;
       
    19 }
       
    20 
       
    21 CompressionParametersObject* get_compression_parameters(PyObject* self, PyObject* args) {
       
    22 	int compressionLevel;
       
    23 	unsigned PY_LONG_LONG sourceSize = 0;
       
    24 	Py_ssize_t dictSize = 0;
       
    25 	ZSTD_compressionParameters params;
       
    26 	CompressionParametersObject* result;
       
    27 
       
    28 	if (!PyArg_ParseTuple(args, "i|Kn", &compressionLevel, &sourceSize, &dictSize)) {
       
    29 		return NULL;
       
    30 	}
       
    31 
       
    32 	params = ZSTD_getCParams(compressionLevel, sourceSize, dictSize);
       
    33 
       
    34 	result = PyObject_New(CompressionParametersObject, &CompressionParametersType);
       
    35 	if (!result) {
       
    36 		return NULL;
       
    37 	}
       
    38 
       
    39 	result->windowLog = params.windowLog;
       
    40 	result->chainLog = params.chainLog;
       
    41 	result->hashLog = params.hashLog;
       
    42 	result->searchLog = params.searchLog;
       
    43 	result->searchLength = params.searchLength;
       
    44 	result->targetLength = params.targetLength;
       
    45 	result->strategy = params.strategy;
       
    46 
       
    47 	return result;
       
    48 }
       
    49 
       
    50 PyObject* estimate_compression_context_size(PyObject* self, PyObject* args) {
       
    51 	CompressionParametersObject* params;
       
    52 	ZSTD_compressionParameters zparams;
       
    53 	PyObject* result;
       
    54 
       
    55 	if (!PyArg_ParseTuple(args, "O!", &CompressionParametersType, &params)) {
       
    56 		return NULL;
       
    57 	}
       
    58 
       
    59 	ztopy_compression_parameters(params, &zparams);
       
    60 	result = PyLong_FromSize_t(ZSTD_estimateCCtxSize(zparams));
       
    61 	return result;
       
    62 }
       
    63 
       
    64 PyDoc_STRVAR(CompressionParameters__doc__,
       
    65 "CompressionParameters: low-level control over zstd compression");
       
    66 
       
    67 static PyObject* CompressionParameters_new(PyTypeObject* subtype, PyObject* args, PyObject* kwargs) {
       
    68 	CompressionParametersObject* self;
       
    69 	unsigned windowLog;
       
    70 	unsigned chainLog;
       
    71 	unsigned hashLog;
       
    72 	unsigned searchLog;
       
    73 	unsigned searchLength;
       
    74 	unsigned targetLength;
       
    75 	unsigned strategy;
       
    76 
       
    77 	if (!PyArg_ParseTuple(args, "IIIIIII", &windowLog, &chainLog, &hashLog, &searchLog,
       
    78 		&searchLength, &targetLength, &strategy)) {
       
    79 		return NULL;
       
    80 	}
       
    81 
       
    82 	if (windowLog < ZSTD_WINDOWLOG_MIN || windowLog > ZSTD_WINDOWLOG_MAX) {
       
    83 		PyErr_SetString(PyExc_ValueError, "invalid window log value");
       
    84 		return NULL;
       
    85 	}
       
    86 
       
    87 	if (chainLog < ZSTD_CHAINLOG_MIN || chainLog > ZSTD_CHAINLOG_MAX) {
       
    88 		PyErr_SetString(PyExc_ValueError, "invalid chain log value");
       
    89 		return NULL;
       
    90 	}
       
    91 
       
    92 	if (hashLog < ZSTD_HASHLOG_MIN || hashLog > ZSTD_HASHLOG_MAX) {
       
    93 		PyErr_SetString(PyExc_ValueError, "invalid hash log value");
       
    94 		return NULL;
       
    95 	}
       
    96 
       
    97 	if (searchLog < ZSTD_SEARCHLOG_MIN || searchLog > ZSTD_SEARCHLOG_MAX) {
       
    98 		PyErr_SetString(PyExc_ValueError, "invalid search log value");
       
    99 		return NULL;
       
   100 	}
       
   101 
       
   102 	if (searchLength < ZSTD_SEARCHLENGTH_MIN || searchLength > ZSTD_SEARCHLENGTH_MAX) {
       
   103 		PyErr_SetString(PyExc_ValueError, "invalid search length value");
       
   104 		return NULL;
       
   105 	}
       
   106 
       
   107 	if (targetLength < ZSTD_TARGETLENGTH_MIN || targetLength > ZSTD_TARGETLENGTH_MAX) {
       
   108 		PyErr_SetString(PyExc_ValueError, "invalid target length value");
       
   109 		return NULL;
       
   110 	}
       
   111 
       
   112 	if (strategy < ZSTD_fast || strategy > ZSTD_btopt) {
       
   113 		PyErr_SetString(PyExc_ValueError, "invalid strategy value");
       
   114 		return NULL;
       
   115 	}
       
   116 
       
   117 	self = (CompressionParametersObject*)subtype->tp_alloc(subtype, 1);
       
   118 	if (!self) {
       
   119 		return NULL;
       
   120 	}
       
   121 
       
   122 	self->windowLog = windowLog;
       
   123 	self->chainLog = chainLog;
       
   124 	self->hashLog = hashLog;
       
   125 	self->searchLog = searchLog;
       
   126 	self->searchLength = searchLength;
       
   127 	self->targetLength = targetLength;
       
   128 	self->strategy = strategy;
       
   129 
       
   130 	return (PyObject*)self;
       
   131 }
       
   132 
       
   133 static void CompressionParameters_dealloc(PyObject* self) {
       
   134 	PyObject_Del(self);
       
   135 }
       
   136 
       
   137 static Py_ssize_t CompressionParameters_length(PyObject* self) {
       
   138 	return 7;
       
   139 };
       
   140 
       
   141 static PyObject* CompressionParameters_item(PyObject* o, Py_ssize_t i) {
       
   142 	CompressionParametersObject* self = (CompressionParametersObject*)o;
       
   143 
       
   144 	switch (i) {
       
   145 	case 0:
       
   146 		return PyLong_FromLong(self->windowLog);
       
   147 	case 1:
       
   148 		return PyLong_FromLong(self->chainLog);
       
   149 	case 2:
       
   150 		return PyLong_FromLong(self->hashLog);
       
   151 	case 3:
       
   152 		return PyLong_FromLong(self->searchLog);
       
   153 	case 4:
       
   154 		return PyLong_FromLong(self->searchLength);
       
   155 	case 5:
       
   156 		return PyLong_FromLong(self->targetLength);
       
   157 	case 6:
       
   158 		return PyLong_FromLong(self->strategy);
       
   159 	default:
       
   160 		PyErr_SetString(PyExc_IndexError, "index out of range");
       
   161 		return NULL;
       
   162 	}
       
   163 }
       
   164 
       
   165 static PySequenceMethods CompressionParameters_sq = {
       
   166 	CompressionParameters_length, /* sq_length */
       
   167 	0,							  /* sq_concat */
       
   168 	0,                            /* sq_repeat */
       
   169 	CompressionParameters_item,   /* sq_item */
       
   170 	0,                            /* sq_ass_item */
       
   171 	0,                            /* sq_contains */
       
   172 	0,                            /* sq_inplace_concat */
       
   173 	0                             /* sq_inplace_repeat */
       
   174 };
       
   175 
       
   176 PyTypeObject CompressionParametersType = {
       
   177 	PyVarObject_HEAD_INIT(NULL, 0)
       
   178 	"CompressionParameters", /* tp_name */
       
   179 	sizeof(CompressionParametersObject), /* tp_basicsize */
       
   180 	0,                         /* tp_itemsize */
       
   181 	(destructor)CompressionParameters_dealloc, /* tp_dealloc */
       
   182 	0,                         /* tp_print */
       
   183 	0,                         /* tp_getattr */
       
   184 	0,                         /* tp_setattr */
       
   185 	0,                         /* tp_compare */
       
   186 	0,                         /* tp_repr */
       
   187 	0,                         /* tp_as_number */
       
   188 	&CompressionParameters_sq, /* tp_as_sequence */
       
   189 	0,                         /* tp_as_mapping */
       
   190 	0,                         /* tp_hash  */
       
   191 	0,                         /* tp_call */
       
   192 	0,                         /* tp_str */
       
   193 	0,                         /* tp_getattro */
       
   194 	0,                         /* tp_setattro */
       
   195 	0,                         /* tp_as_buffer */
       
   196 	Py_TPFLAGS_DEFAULT,        /* tp_flags */
       
   197 	CompressionParameters__doc__, /* tp_doc */
       
   198 	0,                         /* tp_traverse */
       
   199 	0,                         /* tp_clear */
       
   200 	0,                         /* tp_richcompare */
       
   201 	0,                         /* tp_weaklistoffset */
       
   202 	0,                         /* tp_iter */
       
   203 	0,                         /* tp_iternext */
       
   204 	0,                         /* tp_methods */
       
   205 	0,                         /* tp_members */
       
   206 	0,                         /* tp_getset */
       
   207 	0,                         /* tp_base */
       
   208 	0,                         /* tp_dict */
       
   209 	0,                         /* tp_descr_get */
       
   210 	0,                         /* tp_descr_set */
       
   211 	0,                         /* tp_dictoffset */
       
   212 	0,                         /* tp_init */
       
   213 	0,                         /* tp_alloc */
       
   214 	CompressionParameters_new, /* tp_new */
       
   215 };
       
   216 
       
   217 void compressionparams_module_init(PyObject* mod) {
       
   218 	Py_TYPE(&CompressionParametersType) = &PyType_Type;
       
   219 	if (PyType_Ready(&CompressionParametersType) < 0) {
       
   220 		return;
       
   221 	}
       
   222 
       
   223 	Py_IncRef((PyObject*)&CompressionParametersType);
       
   224 	PyModule_AddObject(mod, "CompressionParameters",
       
   225 		(PyObject*)&CompressionParametersType);
       
   226 }