mirror of
https://gitlab.com/spaceti-app/integrations/common/server-sdk.git
synced 2026-07-12 14:00:40 +02:00
114 lines
2.7 KiB
C++
114 lines
2.7 KiB
C++
#include "compression.h"
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#include <QFileInfo>
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#include <QDir>
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#include <zlib.h> // gzip decompress
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namespace core {
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/**
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* @brief Decompress gzip data
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* @param compressed gzip data
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* @return decompressed data
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*/
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QByteArray Compression::decompress(const QByteArray &compressed)
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{
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if (compressed.size() <= 4) {
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qWarning("gUncompress: Input data is truncated");
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return QByteArray();
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}
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QByteArray result;
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int ret;
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z_stream strm;
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static const int CHUNK_SIZE = 1024;
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char out[CHUNK_SIZE];
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/* allocate inflate state */
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strm.zalloc = Z_NULL;
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strm.zfree = Z_NULL;
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strm.opaque = Z_NULL;
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strm.avail_in = compressed.size();
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strm.next_in = (Bytef*)(compressed.data());
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ret = inflateInit2(&strm, 15 + 32); // gzip decoding
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if (ret != Z_OK)
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return QByteArray();
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// run inflate()
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do {
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strm.avail_out = CHUNK_SIZE;
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strm.next_out = (Bytef*)(out);
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ret = inflate(&strm, Z_NO_FLUSH);
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Q_ASSERT(ret != Z_STREAM_ERROR); // state not clobbered
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switch (ret) {
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case Z_NEED_DICT:
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return QByteArray();
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case Z_DATA_ERROR:
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case Z_MEM_ERROR:
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(void)inflateEnd(&strm);
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return QByteArray();
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}
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result.append(out, CHUNK_SIZE - strm.avail_out);
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} while (strm.avail_out == 0);
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// clean up and return
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inflateEnd(&strm);
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// Calculate compression ratio
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// original :200
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// compressed :100
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// ratio = 0.5
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float ratio = (float)compressed.count() / (float)result.count();
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float compression = ratio * 100.0;
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qCInfo(sdkcompress) << "compress data:" << compressed.count()
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<< "uncompressed data:" << result.count()
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<< "compression:" << compression;
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return result;
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}
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/**
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* @brief Return path to source directory
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* @param subpath ( e.g. test/data )
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* @return absolute path to desired subpath in source folder
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*/
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QString Compression::sourcePath(const QString &subpath)
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{
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QDir dir(__FILE__);
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dir.cdUp();
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dir.cdUp();
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dir.cdUp();
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return dir.absoluteFilePath(subpath);
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}
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/**
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* @brief Return data from source directory
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* @param subpath ( e.g. test/data/gizp.src )
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* @return data of file - QByteArray
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*/
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QByteArray Compression::sourceData(const QString &subpath)
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{
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// Get data from file
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QString filePath = sourcePath(subpath);
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if (! QFileInfo::exists(filePath)) {
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qCWarning(sdkcompress) << "path does not exists:" << filePath;
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return QByteArray();
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}
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QFile file(filePath);
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if ( file.open(QIODevice::ReadOnly) )
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return file.readAll();
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return QByteArray();
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}
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} // namespace core
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