Mercurial > hg
view contrib/python-zstandard/c-ext/decompressoriterator.c @ 42822:0f5652f17325
bundlerepo: drop the `baserevision` hack
It is not used anywhere anymore, so we can safely drop it.
author | Pierre-Yves David <pierre-yves.david@octobus.net> |
---|---|
date | Fri, 30 Aug 2019 17:46:47 +0200 |
parents | 675775c33ab6 |
children | e92ca942ddca |
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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. */ #include "python-zstandard.h" #define min(a, b) (((a) < (b)) ? (a) : (b)) extern PyObject* ZstdError; PyDoc_STRVAR(ZstdDecompressorIterator__doc__, "Represents an iterator of decompressed data.\n" ); static void ZstdDecompressorIterator_dealloc(ZstdDecompressorIterator* self) { Py_XDECREF(self->decompressor); Py_XDECREF(self->reader); if (self->buffer.buf) { PyBuffer_Release(&self->buffer); memset(&self->buffer, 0, sizeof(self->buffer)); } if (self->input.src) { PyMem_Free((void*)self->input.src); self->input.src = NULL; } PyObject_Del(self); } static PyObject* ZstdDecompressorIterator_iter(PyObject* self) { Py_INCREF(self); return self; } static DecompressorIteratorResult read_decompressor_iterator(ZstdDecompressorIterator* self) { size_t zresult; PyObject* chunk; DecompressorIteratorResult result; size_t oldInputPos = self->input.pos; result.chunk = NULL; chunk = PyBytes_FromStringAndSize(NULL, self->outSize); if (!chunk) { result.errored = 1; return result; } self->output.dst = PyBytes_AsString(chunk); self->output.size = self->outSize; self->output.pos = 0; Py_BEGIN_ALLOW_THREADS zresult = ZSTD_decompressStream(self->decompressor->dctx, &self->output, &self->input); Py_END_ALLOW_THREADS /* We're done with the pointer. Nullify to prevent anyone from getting a handle on a Python object. */ self->output.dst = NULL; if (ZSTD_isError(zresult)) { Py_DECREF(chunk); PyErr_Format(ZstdError, "zstd decompress error: %s", ZSTD_getErrorName(zresult)); result.errored = 1; return result; } self->readCount += self->input.pos - oldInputPos; /* Frame is fully decoded. Input exhausted and output sitting in buffer. */ if (0 == zresult) { self->finishedInput = 1; self->finishedOutput = 1; } /* If it produced output data, return it. */ if (self->output.pos) { if (self->output.pos < self->outSize) { if (safe_pybytes_resize(&chunk, self->output.pos)) { Py_XDECREF(chunk); result.errored = 1; return result; } } } else { Py_DECREF(chunk); chunk = NULL; } result.errored = 0; result.chunk = chunk; return result; } static PyObject* ZstdDecompressorIterator_iternext(ZstdDecompressorIterator* self) { PyObject* readResult = NULL; char* readBuffer; Py_ssize_t readSize; Py_ssize_t bufferRemaining; DecompressorIteratorResult result; if (self->finishedOutput) { PyErr_SetString(PyExc_StopIteration, "output flushed"); return NULL; } /* If we have data left in the input, consume it. */ if (self->input.pos < self->input.size) { result = read_decompressor_iterator(self); if (result.chunk || result.errored) { return result.chunk; } /* Else fall through to get more data from input. */ } read_from_source: if (!self->finishedInput) { if (self->reader) { readResult = PyObject_CallMethod(self->reader, "read", "I", self->inSize); if (!readResult) { return NULL; } PyBytes_AsStringAndSize(readResult, &readBuffer, &readSize); } else { assert(self->buffer.buf); /* Only support contiguous C arrays for now */ assert(self->buffer.strides == NULL && self->buffer.suboffsets == NULL); assert(self->buffer.itemsize == 1); /* TODO avoid memcpy() below */ readBuffer = (char *)self->buffer.buf + self->bufferOffset; bufferRemaining = self->buffer.len - self->bufferOffset; readSize = min(bufferRemaining, (Py_ssize_t)self->inSize); self->bufferOffset += readSize; } if (readSize) { if (!self->readCount && self->skipBytes) { assert(self->skipBytes < self->inSize); if ((Py_ssize_t)self->skipBytes >= readSize) { PyErr_SetString(PyExc_ValueError, "skip_bytes larger than first input chunk; " "this scenario is currently unsupported"); Py_XDECREF(readResult); return NULL; } readBuffer = readBuffer + self->skipBytes; readSize -= self->skipBytes; } /* Copy input into previously allocated buffer because it can live longer than a single function call and we don't want to keep a ref to a Python object around. This could be changed... */ memcpy((void*)self->input.src, readBuffer, readSize); self->input.size = readSize; self->input.pos = 0; } /* No bytes on first read must mean an empty input stream. */ else if (!self->readCount) { self->finishedInput = 1; self->finishedOutput = 1; Py_XDECREF(readResult); PyErr_SetString(PyExc_StopIteration, "empty input"); return NULL; } else { self->finishedInput = 1; } /* We've copied the data managed by memory. Discard the Python object. */ Py_XDECREF(readResult); } result = read_decompressor_iterator(self); if (result.errored || result.chunk) { return result.chunk; } /* No new output data. Try again unless we know there is no more data. */ if (!self->finishedInput) { goto read_from_source; } PyErr_SetString(PyExc_StopIteration, "input exhausted"); return NULL; } PyTypeObject ZstdDecompressorIteratorType = { PyVarObject_HEAD_INIT(NULL, 0) "zstd.ZstdDecompressorIterator", /* tp_name */ sizeof(ZstdDecompressorIterator), /* tp_basicsize */ 0, /* tp_itemsize */ (destructor)ZstdDecompressorIterator_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 */ ZstdDecompressorIterator__doc__, /* tp_doc */ 0, /* tp_traverse */ 0, /* tp_clear */ 0, /* tp_richcompare */ 0, /* tp_weaklistoffset */ ZstdDecompressorIterator_iter, /* tp_iter */ (iternextfunc)ZstdDecompressorIterator_iternext, /* tp_iternext */ 0, /* 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 decompressoriterator_module_init(PyObject* mod) { Py_TYPE(&ZstdDecompressorIteratorType) = &PyType_Type; if (PyType_Ready(&ZstdDecompressorIteratorType) < 0) { return; } }