Chris@95: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
Chris@95: 
Chris@95: /*
Chris@95:     Sonic Visualiser
Chris@95:     An audio file viewer and annotation editor.
Chris@95:     Centre for Digital Music, Queen Mary, University of London.
Chris@95:     This file copyright 2006 Chris Cannam.
Chris@95:     
Chris@95:     This program is free software; you can redistribute it and/or
Chris@95:     modify it under the terms of the GNU General Public License as
Chris@95:     published by the Free Software Foundation; either version 2 of the
Chris@95:     License, or (at your option) any later version.  See the file
Chris@95:     COPYING included with this distribution for more information.
Chris@95: */
Chris@95: 
Chris@95: #ifndef _FILE_READ_THREAD_H_
Chris@95: #define _FILE_READ_THREAD_H_
Chris@95: 
Chris@95: #include <QThread>
Chris@95: #include <QMutex>
Chris@95: #include <QWaitCondition>
Chris@95: 
Chris@95: #include <map>
Chris@95: #include <set>
Chris@95: 
Chris@95: #include <stdint.h>
Chris@95: 
Chris@95: class FileReadThread : public QThread
Chris@95: {
Chris@95:     Q_OBJECT
Chris@95: 
Chris@95: public:
Chris@95:     FileReadThread();
Chris@95: 
Chris@95:     virtual void run();
Chris@95:     virtual void finish();
Chris@95: 
Chris@95:     struct Request {
Chris@95:         int fd;
Chris@95:         QMutex *mutex; // used to synchronise access to fd; may be null
Chris@95:         off_t start;
Chris@95:         size_t size;
Chris@95:         char *data; // caller is responsible for allocating and deallocating
Chris@95:     };
Chris@95:     
Chris@95:     virtual int request(const Request &request);
Chris@95:     virtual void cancel(int token);
Chris@95: 
Chris@95:     virtual bool isReady(int token);
Chris@95:     virtual bool isCancelled(int token); // and safe to delete
Chris@95:     virtual bool getRequest(int token, Request &request);
Chris@95:     virtual void done(int token);
Chris@95: 
Chris@95: signals:
Chris@95:     void ready(int token, bool successful); 
Chris@95:     void cancelled(int token);
Chris@95:     
Chris@95: protected:
Chris@95:     int m_nextToken;
Chris@95:     bool m_exiting;
Chris@95:     
Chris@95:     typedef std::map<int, Request> RequestQueue;
Chris@95:     RequestQueue m_queue;
Chris@95:     RequestQueue m_cancelledRequests;
Chris@95:     RequestQueue m_readyRequests;
Chris@95:     std::set<int> m_newlyCancelled;
Chris@95: 
Chris@95:     QMutex m_mutex;
Chris@95:     QWaitCondition m_condition;
Chris@95: 
Chris@95:     void process();
Chris@95:     void notifyCancelled();
Chris@95: };
Chris@95: 
Chris@95: #endif