Mercurial > hg > orthanc
diff Core/Compression/ZlibCompressor.cpp @ 0:3959d33612cc
initial commit
author | Sebastien Jodogne <s.jodogne@gmail.com> |
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date | Thu, 19 Jul 2012 14:32:22 +0200 |
parents | |
children | a15e90e5d6fc |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/Core/Compression/ZlibCompressor.cpp Thu Jul 19 14:32:22 2012 +0200 @@ -0,0 +1,125 @@ +/** + * Palantir - A Lightweight, RESTful DICOM Store + * Copyright (C) 2012 Medical Physics Department, CHU of Liege, + * Belgium + * + * This program is free software: you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, either version 3 of the + * License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + **/ + + +#include "ZlibCompressor.h" + +#include <stdio.h> +#include <string.h> +#include <zlib.h> +#include "../PalantirException.h" + +namespace Palantir +{ + void ZlibCompressor::SetCompressionLevel(uint8_t level) + { + if (level >= 10) + { + throw PalantirException("Zlib compression level must be between 0 (no compression) and 9 (highest compression"); + } + } + + + void ZlibCompressor::Compress(std::string& compressed, + const void* uncompressed, + size_t uncompressedSize) + { + if (uncompressedSize == 0) + { + compressed.clear(); + return; + } + + uLongf compressedSize = compressBound(uncompressedSize); + compressed.resize(compressedSize + sizeof(size_t)); + + int error = compress2 + (reinterpret_cast<uint8_t*>(&compressed[0]) + sizeof(size_t), + &compressedSize, + const_cast<Bytef *>(static_cast<const Bytef *>(uncompressed)), + uncompressedSize, + compressionLevel_); + + memcpy(&compressed[0], &uncompressedSize, sizeof(size_t)); + + if (error == Z_OK) + { + compressed.resize(compressedSize + sizeof(size_t)); + return; + } + else + { + compressed.clear(); + + switch (error) + { + case Z_MEM_ERROR: + throw PalantirException(ErrorCode_NotEnoughMemory); + + default: + throw PalantirException(ErrorCode_InternalError); + } + } + } + + + void ZlibCompressor::Uncompress(std::string& uncompressed, + const void* compressed, + size_t compressedSize) + { + if (compressedSize == 0) + { + uncompressed.clear(); + return; + } + + if (compressedSize < sizeof(size_t)) + { + throw PalantirException("Zlib: The compressed buffer is ill-formed"); + } + + size_t uncompressedLength; + memcpy(&uncompressedLength, compressed, sizeof(size_t)); + uncompressed.resize(uncompressedLength); + + uLongf tmp = uncompressedLength; + int error = uncompress + (reinterpret_cast<uint8_t*>(&uncompressed[0]), + &tmp, + reinterpret_cast<const uint8_t*>(compressed) + sizeof(size_t), + compressedSize - sizeof(size_t)); + + if (error != Z_OK) + { + uncompressed.clear(); + + switch (error) + { + case Z_DATA_ERROR: + throw PalantirException("Zlib: Corrupted or incomplete compressed buffer"); + + case Z_MEM_ERROR: + throw PalantirException(ErrorCode_NotEnoughMemory); + + default: + throw PalantirException(ErrorCode_InternalError); + } + } + } +}