view contrib/python-zstandard/c-ext/decompressobj.c @ 36747:4c71a26a4009

sslutil: some more forcebytes() on some exception messages

At this point, test-https.t no longer dumps tracebacks
everywhere. Instead, we get some results that look like we're not
adequately finding things in hg's configuration, which should be
manageable (if somewhat annoying to find and fix.)

Differential Revision: https://phab.mercurial-scm.org/D2690

/**
* 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) {
	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;

	/* Constructor should ensure stream is populated. */
	assert(self->decompressor->dstream);

	if (self->finished) {
		PyErr_SetString(ZstdError, "cannot use a decompressobj multiple times");
		return NULL;
	}

#if PY_MAJOR_VERSION >= 3
	if (!PyArg_ParseTuple(args, "y#:decompress",
#else
	if (!PyArg_ParseTuple(args, "s#:decompress",
#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->decompressor->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_CLEAR(result);

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;
	}
}