contrib/python-zstandard/c-ext/decompressobj.c
changeset 30435 b86a448a2965
child 30895 c32454d69b85
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/contrib/python-zstandard/c-ext/decompressobj.c	Thu Nov 10 22:15:58 2016 -0800
@@ -0,0 +1,170 @@
+/**
+* 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;
+
+PyDoc_STRVAR(DecompressionObj__doc__,
+"Perform decompression using a standard library compatible API.\n"
+);
+
+static void DecompressionObj_dealloc(ZstdDecompressionObj* self) {
+	if (self->dstream) {
+		ZSTD_freeDStream(self->dstream);
+		self->dstream = NULL;
+	}
+
+	Py_XDECREF(self->decompressor);
+
+	PyObject_Del(self);
+}
+
+static PyObject* DecompressionObj_decompress(ZstdDecompressionObj* self, PyObject* args) {
+	const char* source;
+	Py_ssize_t sourceSize;
+	size_t zresult;
+	ZSTD_inBuffer input;
+	ZSTD_outBuffer output;
+	size_t outSize = ZSTD_DStreamOutSize();
+	PyObject* result = NULL;
+	Py_ssize_t resultSize = 0;
+
+	if (self->finished) {
+		PyErr_SetString(ZstdError, "cannot use a decompressobj multiple times");
+		return NULL;
+	}
+
+#if PY_MAJOR_VERSION >= 3
+	if (!PyArg_ParseTuple(args, "y#",
+#else
+	if (!PyArg_ParseTuple(args, "s#",
+#endif
+		&source, &sourceSize)) {
+		return NULL;
+	}
+
+	input.src = source;
+	input.size = sourceSize;
+	input.pos = 0;
+
+	output.dst = PyMem_Malloc(outSize);
+	if (!output.dst) {
+		PyErr_NoMemory();
+		return NULL;
+	}
+	output.size = outSize;
+	output.pos = 0;
+
+	/* Read input until exhausted. */
+	while (input.pos < input.size) {
+		Py_BEGIN_ALLOW_THREADS
+		zresult = ZSTD_decompressStream(self->dstream, &output, &input);
+		Py_END_ALLOW_THREADS
+
+		if (ZSTD_isError(zresult)) {
+			PyErr_Format(ZstdError, "zstd decompressor error: %s",
+				ZSTD_getErrorName(zresult));
+			result = NULL;
+			goto finally;
+		}
+
+		if (0 == zresult) {
+			self->finished = 1;
+		}
+
+		if (output.pos) {
+			if (result) {
+				resultSize = PyBytes_GET_SIZE(result);
+				if (-1 == _PyBytes_Resize(&result, resultSize + output.pos)) {
+					goto except;
+				}
+
+				memcpy(PyBytes_AS_STRING(result) + resultSize,
+					output.dst, output.pos);
+			}
+			else {
+				result = PyBytes_FromStringAndSize(output.dst, output.pos);
+				if (!result) {
+					goto except;
+				}
+			}
+
+			output.pos = 0;
+		}
+	}
+
+	if (!result) {
+		result = PyBytes_FromString("");
+	}
+
+	goto finally;
+
+except:
+	Py_DecRef(result);
+	result = NULL;
+
+finally:
+	PyMem_Free(output.dst);
+
+	return result;
+}
+
+static PyMethodDef DecompressionObj_methods[] = {
+	{ "decompress", (PyCFunction)DecompressionObj_decompress,
+	  METH_VARARGS, PyDoc_STR("decompress data") },
+	{ NULL, NULL }
+};
+
+PyTypeObject ZstdDecompressionObjType = {
+	PyVarObject_HEAD_INIT(NULL, 0)
+	"zstd.ZstdDecompressionObj",    /* tp_name */
+	sizeof(ZstdDecompressionObj),   /* tp_basicsize */
+	0,                              /* tp_itemsize */
+	(destructor)DecompressionObj_dealloc, /* tp_dealloc */
+	0,                              /* tp_print */
+	0,                              /* tp_getattr */
+	0,                              /* tp_setattr */
+	0,                              /* tp_compare */
+	0,                              /* tp_repr */
+	0,                              /* tp_as_number */
+	0,                              /* tp_as_sequence */
+	0,                              /* tp_as_mapping */
+	0,                              /* tp_hash */
+	0,                              /* tp_call */
+	0,                              /* tp_str */
+	0,                              /* tp_getattro */
+	0,                              /* tp_setattro */
+	0,                              /* tp_as_buffer */
+	Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /* tp_flags */
+	DecompressionObj__doc__,        /* tp_doc */
+	0,                              /* tp_traverse */
+	0,                              /* tp_clear */
+	0,                              /* tp_richcompare */
+	0,                              /* tp_weaklistoffset */
+	0,                              /* tp_iter */
+	0,                              /* tp_iternext */
+	DecompressionObj_methods,       /* tp_methods */
+	0,                              /* tp_members */
+	0,                              /* tp_getset */
+	0,                              /* tp_base */
+	0,                              /* tp_dict */
+	0,                              /* tp_descr_get */
+	0,                              /* tp_descr_set */
+	0,                              /* tp_dictoffset */
+	0,                              /* tp_init */
+	0,                              /* tp_alloc */
+	PyType_GenericNew,              /* tp_new */
+};
+
+void decompressobj_module_init(PyObject* module) {
+	Py_TYPE(&ZstdDecompressionObjType) = &PyType_Type;
+	if (PyType_Ready(&ZstdDecompressionObjType) < 0) {
+		return;
+	}
+}