JackMessageBuffer.cpp
/*
* Copyright (C) 2004 Rui Nuno Capela, Steve Harris
* Copyright (C) 2008 Nedko Arnaudov
* Copyright (C) 2008 Grame
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
*/
#include "JackMessageBuffer.h"
#include "JackGlobals.h"
#include "JackError.h"
#include "JackTime.h"
namespace Jack
{
JackMessageBuffer* JackMessageBuffer::fInstance = NULL;
JackMessageBuffer::JackMessageBuffer()
:fInit(NULL),
fInitArg(NULL),
fThread(this),
fGuard(),
fInBuffer(0),
fOutBuffer(0),
fOverruns(0),
fRunning(false)
{}
JackMessageBuffer::~JackMessageBuffer()
{}
bool JackMessageBuffer::Start()
{
// Before StartSync()...
fRunning = true;
if (fThread.StartSync() == 0) {
return true;
} else {
fRunning = false;
return false;
}
}
bool JackMessageBuffer::Stop()
{
if (fOverruns > 0) {
jack_error("WARNING: %d message buffer overruns!", fOverruns);
} else {
jack_log("no message buffer overruns");
}
if (fGuard.Lock()) {
fRunning = false;
fGuard.Signal();
fGuard.Unlock();
fThread.Stop();
} else {
fThread.Kill();
}
Flush();
return true;
}
void JackMessageBuffer::Flush()
{
while (fOutBuffer != fInBuffer) {
jack_log_function(fBuffers[fOutBuffer].level, fBuffers[fOutBuffer].message);
fOutBuffer = MB_NEXT(fOutBuffer);
}
}
void JackMessageBuffer::AddMessage(int level, const char *message)
{
if (fGuard.Trylock()) {
fBuffers[fInBuffer].level = level;
strncpy(fBuffers[fInBuffer].message, message, MB_BUFFERSIZE);
fInBuffer = MB_NEXT(fInBuffer);
fGuard.Signal();
fGuard.Unlock();
} else { /* lock collision */
INC_ATOMIC(&fOverruns);
}
}
bool JackMessageBuffer::Execute()
{
if (fGuard.Lock()) {
while (fRunning) {
fGuard.Wait();
/* the client asked for all threads to run a thread
initialization callback, which includes us.
*/
if (fInit) {
fInit(fInitArg);
fInit = NULL;
/* and we're done */
fGuard.Signal();
}
/* releasing the mutex reduces contention */
fGuard.Unlock();
Flush();
fGuard.Lock();
}
fGuard.Unlock();
} else {
jack_error("JackMessageBuffer::Execute lock cannot be taken");
}
return false;
}
bool JackMessageBuffer::Create()
{
if (fInstance == NULL) {
fInstance = new JackMessageBuffer();
if (!fInstance->Start()) {
jack_error("JackMessageBuffer::Create cannot start thread");
delete fInstance;
fInstance = NULL;
return false;
}
}
return true;
}
bool JackMessageBuffer::Destroy()
{
if (fInstance != NULL) {
fInstance->Stop();
delete fInstance;
fInstance = NULL;
return true;
} else {
return false;
}
}
void JackMessageBufferAdd(int level, const char *message)
{
if (Jack::JackMessageBuffer::fInstance == NULL) {
/* Unable to print message with realtime safety. Complain and print it anyway. */
jack_log_function(LOG_LEVEL_ERROR, "messagebuffer not initialized, skip message");
} else {
Jack::JackMessageBuffer::fInstance->AddMessage(level, message);
}
}
int JackMessageBuffer::SetInitCallback(JackThreadInitCallback callback, void *arg)
{
if (fInstance && callback && fRunning && fGuard.Lock()) {
/* set up the callback */
fInitArg = arg;
fInit = callback;
#ifndef WIN32
// wake msg buffer thread
fGuard.Signal();
// wait for it to be done
fGuard.Wait();
// and we're done
fGuard.Unlock();
#else
/*
The condition variable emulation code does not work reliably on Windows (lost signal).
So use a "hackish" way to signal/wait for the result.
Probaly better in the long term : use pthread-win32 (http://sourceware.org/pthreads-win32/`
*/
fGuard.Unlock();
int count = 0;
while (fInit && ++count < 1000) {
/* wake msg buffer thread */
fGuard.Signal();
JackSleep(1000);
}
if (count == 1000) {
jack_error("JackMessageBuffer::SetInitCallback : signal lost");
return -1;
}
#endif
return 0;
}
jack_error("JackMessageBuffer::SetInitCallback : callback could not be executed");
return -1;
}
};
Jack
Definition: JackAC3Encoder.cpp:30
jack_error
SERVER_EXPORT void jack_error(const char *fmt,...)
Definition: JackError.cpp:92
jack_log
SERVER_EXPORT void jack_log(const char *fmt,...)
Definition: JackError.cpp:108