Mercurial > hg > svcore
view data/fileio/BZipFileDevice.cpp @ 1591:6e68bd92ee21 bqaudiostream
Add flac metadata example
author | Chris Cannam |
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date | Mon, 21 Jan 2019 11:45:51 +0000 |
parents | 48e9f538e6e9 |
children | 70e172e6cc59 |
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/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */ /* Sonic Visualiser An audio file viewer and annotation editor. Centre for Digital Music, Queen Mary, University of London. This file copyright 2006 Chris Cannam. 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 2 of the License, or (at your option) any later version. See the file COPYING included with this distribution for more information. */ #include "BZipFileDevice.h" #include <bzlib.h> #include <iostream> #include "base/Debug.h" // for dup: #ifdef _MSC_VER #include <io.h> #else #include <unistd.h> #endif BZipFileDevice::BZipFileDevice(QString fileName) : m_fileName(fileName), m_qfile(fileName), m_file(0), m_bzFile(0), m_atEnd(true), m_ok(true) { } BZipFileDevice::~BZipFileDevice() { // SVDEBUG << "BZipFileDevice::~BZipFileDevice(" << m_fileName << ")" << endl; if (m_bzFile) close(); } bool BZipFileDevice::isOK() const { return m_ok; } bool BZipFileDevice::open(OpenMode mode) { setErrorString(""); if (m_bzFile) { setErrorString(tr("File is already open")); return false; } if (mode & Append) { setErrorString(tr("Append mode not supported")); m_ok = false; return false; } if ((mode & (ReadOnly | WriteOnly)) == 0) { setErrorString(tr("File access mode not specified")); m_ok = false; return false; } if ((mode & ReadOnly) && (mode & WriteOnly)) { setErrorString(tr("Read and write modes both specified")); m_ok = false; return false; } // This is all going to be a bit silly. // // We open the file with QFile so as not to have to worry about locale // support ourselves (especially on Windows). Then we get a fd from // QFile and "convert" it to a FILE* using fdopen because that is what // the bz2 library needs for reading and writing an already-open file. // // fdopen takes over the fd it is given, and will close it when fclose // is called. (We must call fclose, because it's needed to avoid // leaking the file stream structure.) // // But QFile will also close its fd, either when we call QFile::close // or on destruction -- there doesn't seem to be a way to avoid that // for a file that QFile opened. // // So we have to add an extra dup() in to the fdopen to avoid a double // close. // // Note that bz2 will *not* fclose the FILE* it was passed, so we // don't have a problem with calling both bzWriteClose and fclose. if (mode & WriteOnly) { if (!m_qfile.open(QIODevice::WriteOnly)) { setErrorString(tr("Failed to open file for writing")); m_ok = false; return false; } m_file = fdopen(dup(m_qfile.handle()), "wb"); if (!m_file) { setErrorString(tr("Failed to open file handle for writing")); m_qfile.close(); m_ok = false; return false; } int bzError = BZ_OK; m_bzFile = BZ2_bzWriteOpen(&bzError, m_file, 9, 0, 0); if (!m_bzFile) { fclose(m_file); m_file = 0; m_qfile.close(); setErrorString(tr("Failed to open bzip2 stream for writing")); m_ok = false; return false; } // cerr << "BZipFileDevice: opened \"" << m_fileName << "\" for writing" << endl; setErrorString(QString()); setOpenMode(mode); return true; } if (mode & ReadOnly) { if (!m_qfile.open(QIODevice::ReadOnly)) { setErrorString(tr("Failed to open file for reading")); m_ok = false; return false; } m_file = fdopen(dup(m_qfile.handle()), "rb"); if (!m_file) { setErrorString(tr("Failed to open file handle for reading")); m_ok = false; return false; } int bzError = BZ_OK; m_bzFile = BZ2_bzReadOpen(&bzError, m_file, 0, 0, NULL, 0); if (!m_bzFile) { fclose(m_file); m_file = 0; m_qfile.close(); setErrorString(tr("Failed to open bzip2 stream for reading")); m_ok = false; return false; } // cerr << "BZipFileDevice: opened \"" << m_fileName << "\" for reading" << endl; m_atEnd = false; setErrorString(QString()); setOpenMode(mode); return true; } setErrorString(tr("Internal error (open for neither read nor write)")); m_ok = false; return false; } void BZipFileDevice::close() { if (!m_bzFile) { setErrorString(tr("File not open")); m_ok = false; return; } int bzError = BZ_OK; if (openMode() & WriteOnly) { unsigned int in = 0, out = 0; BZ2_bzWriteClose(&bzError, m_bzFile, 0, &in, &out); // cerr << "Wrote bzip2 stream (in=" << in << ", out=" << out << ")" << endl; if (bzError != BZ_OK) { setErrorString(tr("bzip2 stream write close error")); } fclose(m_file); m_qfile.close(); m_bzFile = 0; m_file = 0; m_ok = false; return; } if (openMode() & ReadOnly) { BZ2_bzReadClose(&bzError, m_bzFile); if (bzError != BZ_OK) { setErrorString(tr("bzip2 stream read close error")); } fclose(m_file); m_qfile.close(); m_bzFile = 0; m_file = 0; m_ok = false; return; } setErrorString(tr("Internal error (close for neither read nor write)")); return; } qint64 BZipFileDevice::readData(char *data, qint64 maxSize) { if (m_atEnd) return 0; int bzError = BZ_OK; int read = BZ2_bzRead(&bzError, m_bzFile, data, int(maxSize)); // SVDEBUG << "BZipFileDevice::readData: requested " << maxSize << ", read " << read << endl; if (bzError != BZ_OK) { if (bzError != BZ_STREAM_END) { cerr << "BZipFileDevice::readData: error condition" << endl; setErrorString(tr("bzip2 stream read error")); m_ok = false; return -1; } else { // SVDEBUG << "BZipFileDevice::readData: reached end of file" << endl; m_atEnd = true; } } return read; } qint64 BZipFileDevice::writeData(const char *data, qint64 maxSize) { int bzError = BZ_OK; BZ2_bzWrite(&bzError, m_bzFile, (void *)data, int(maxSize)); // SVDEBUG << "BZipFileDevice::writeData: " << maxSize << " to write" << endl; if (bzError != BZ_OK) { cerr << "BZipFileDevice::writeData: error condition" << endl; setErrorString("bzip2 stream write error"); m_ok = false; return -1; } // SVDEBUG << "BZipFileDevice::writeData: wrote " << maxSize << endl; return maxSize; }