mirror of
https://github.com/kasmtech/KasmVNC.git
synced 2024-11-25 01:24:04 +01:00
366 lines
9.2 KiB
C++
366 lines
9.2 KiB
C++
/* Copyright 2015 Pierre Ossman for Cendio AB
|
|
*
|
|
* This 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.
|
|
*
|
|
* This software 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 software; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
|
|
* USA.
|
|
*/
|
|
|
|
#include <assert.h>
|
|
#include <string.h>
|
|
|
|
#include <rfb/CConnection.h>
|
|
#include <rfb/DecodeManager.h>
|
|
#include <rfb/Decoder.h>
|
|
#include <rfb/Region.h>
|
|
|
|
#include <rfb/LogWriter.h>
|
|
|
|
#include <rdr/Exception.h>
|
|
#include <rdr/MemOutStream.h>
|
|
|
|
#include <os/Mutex.h>
|
|
|
|
using namespace rfb;
|
|
|
|
static LogWriter vlog("DecodeManager");
|
|
|
|
DecodeManager::DecodeManager(CConnection *conn) :
|
|
conn(conn), threadException(NULL)
|
|
{
|
|
size_t cpuCount;
|
|
|
|
memset(decoders, 0, sizeof(decoders));
|
|
|
|
queueMutex = new os::Mutex();
|
|
producerCond = new os::Condition(queueMutex);
|
|
consumerCond = new os::Condition(queueMutex);
|
|
|
|
cpuCount = os::Thread::getSystemCPUCount();
|
|
if (cpuCount == 0) {
|
|
vlog.error("Unable to determine the number of CPU cores on this system");
|
|
cpuCount = 1;
|
|
} else {
|
|
vlog.info("Detected %d CPU core(s)", (int)cpuCount);
|
|
// No point creating more threads than this, they'll just end up
|
|
// wasting CPU fighting for locks
|
|
if (cpuCount > 4)
|
|
cpuCount = 4;
|
|
// The overhead of threading is small, but not small enough to
|
|
// ignore on single CPU systems
|
|
if (cpuCount == 1)
|
|
vlog.info("Decoding data on main thread");
|
|
else
|
|
vlog.info("Creating %d decoder thread(s)", (int)cpuCount);
|
|
}
|
|
|
|
if (cpuCount == 1) {
|
|
// Threads are not used on single CPU machines
|
|
freeBuffers.push_back(new rdr::MemOutStream());
|
|
return;
|
|
}
|
|
|
|
while (cpuCount--) {
|
|
// Twice as many possible entries in the queue as there
|
|
// are worker threads to make sure they don't stall
|
|
freeBuffers.push_back(new rdr::MemOutStream());
|
|
freeBuffers.push_back(new rdr::MemOutStream());
|
|
|
|
threads.push_back(new DecodeThread(this));
|
|
}
|
|
}
|
|
|
|
DecodeManager::~DecodeManager()
|
|
{
|
|
while (!threads.empty()) {
|
|
delete threads.back();
|
|
threads.pop_back();
|
|
}
|
|
|
|
delete threadException;
|
|
|
|
while (!freeBuffers.empty()) {
|
|
delete freeBuffers.back();
|
|
freeBuffers.pop_back();
|
|
}
|
|
|
|
delete consumerCond;
|
|
delete producerCond;
|
|
delete queueMutex;
|
|
|
|
for (size_t i = 0; i < sizeof(decoders)/sizeof(decoders[0]); i++)
|
|
delete decoders[i];
|
|
}
|
|
|
|
void DecodeManager::decodeRect(const Rect& r, int encoding,
|
|
ModifiablePixelBuffer* pb)
|
|
{
|
|
Decoder *decoder;
|
|
rdr::MemOutStream *bufferStream;
|
|
|
|
QueueEntry *entry;
|
|
|
|
assert(pb != NULL);
|
|
|
|
if (!Decoder::supported(encoding)) {
|
|
vlog.error("Unknown encoding %d", encoding);
|
|
throw rdr::Exception("Unknown encoding");
|
|
}
|
|
|
|
if (!decoders[encoding]) {
|
|
decoders[encoding] = Decoder::createDecoder(encoding);
|
|
if (!decoders[encoding]) {
|
|
vlog.error("Unknown encoding %d", encoding);
|
|
throw rdr::Exception("Unknown encoding");
|
|
}
|
|
}
|
|
|
|
decoder = decoders[encoding];
|
|
|
|
// Fast path for single CPU machines to avoid the context
|
|
// switching overhead
|
|
if (threads.empty()) {
|
|
bufferStream = freeBuffers.front();
|
|
bufferStream->clear();
|
|
decoder->readRect(r, conn->getInStream(), conn->cp, bufferStream);
|
|
decoder->decodeRect(r, bufferStream->data(), bufferStream->length(),
|
|
conn->cp, pb);
|
|
return;
|
|
}
|
|
|
|
// Wait for an available memory buffer
|
|
queueMutex->lock();
|
|
|
|
while (freeBuffers.empty())
|
|
producerCond->wait();
|
|
|
|
// Don't pop the buffer in case we throw an exception
|
|
// whilst reading
|
|
bufferStream = freeBuffers.front();
|
|
|
|
queueMutex->unlock();
|
|
|
|
// First check if any thread has encountered a problem
|
|
throwThreadException();
|
|
|
|
// Read the rect
|
|
bufferStream->clear();
|
|
decoder->readRect(r, conn->getInStream(), conn->cp, bufferStream);
|
|
|
|
// Then try to put it on the queue
|
|
entry = new QueueEntry;
|
|
|
|
entry->active = false;
|
|
entry->rect = r;
|
|
entry->encoding = encoding;
|
|
entry->decoder = decoder;
|
|
entry->cp = &conn->cp;
|
|
entry->pb = pb;
|
|
entry->bufferStream = bufferStream;
|
|
|
|
decoder->getAffectedRegion(r, bufferStream->data(),
|
|
bufferStream->length(), conn->cp,
|
|
&entry->affectedRegion);
|
|
|
|
queueMutex->lock();
|
|
|
|
// The workers add buffers to the end so it's safe to assume
|
|
// the front is still the same buffer
|
|
freeBuffers.pop_front();
|
|
|
|
workQueue.push_back(entry);
|
|
|
|
// We only put a single entry on the queue so waking a single
|
|
// thread is sufficient
|
|
consumerCond->signal();
|
|
|
|
queueMutex->unlock();
|
|
}
|
|
|
|
void DecodeManager::flush()
|
|
{
|
|
queueMutex->lock();
|
|
|
|
while (!workQueue.empty())
|
|
producerCond->wait();
|
|
|
|
queueMutex->unlock();
|
|
|
|
throwThreadException();
|
|
}
|
|
|
|
void DecodeManager::setThreadException(const rdr::Exception& e)
|
|
{
|
|
os::AutoMutex a(queueMutex);
|
|
|
|
if (threadException != NULL)
|
|
return;
|
|
|
|
threadException = new rdr::Exception("Exception on worker thread: %s", e.str());
|
|
}
|
|
|
|
void DecodeManager::throwThreadException()
|
|
{
|
|
os::AutoMutex a(queueMutex);
|
|
|
|
if (threadException == NULL)
|
|
return;
|
|
|
|
rdr::Exception e(*threadException);
|
|
|
|
delete threadException;
|
|
threadException = NULL;
|
|
|
|
throw e;
|
|
}
|
|
|
|
DecodeManager::DecodeThread::DecodeThread(DecodeManager* manager)
|
|
{
|
|
this->manager = manager;
|
|
|
|
stopRequested = false;
|
|
|
|
start();
|
|
}
|
|
|
|
DecodeManager::DecodeThread::~DecodeThread()
|
|
{
|
|
stop();
|
|
wait();
|
|
}
|
|
|
|
void DecodeManager::DecodeThread::stop()
|
|
{
|
|
os::AutoMutex a(manager->queueMutex);
|
|
|
|
if (!isRunning())
|
|
return;
|
|
|
|
stopRequested = true;
|
|
|
|
// We can't wake just this thread, so wake everyone
|
|
manager->consumerCond->broadcast();
|
|
}
|
|
|
|
void DecodeManager::DecodeThread::worker()
|
|
{
|
|
manager->queueMutex->lock();
|
|
|
|
while (!stopRequested) {
|
|
DecodeManager::QueueEntry *entry;
|
|
|
|
// Look for an available entry in the work queue
|
|
entry = findEntry();
|
|
if (entry == NULL) {
|
|
// Wait and try again
|
|
manager->consumerCond->wait();
|
|
continue;
|
|
}
|
|
|
|
// This is ours now
|
|
entry->active = true;
|
|
|
|
manager->queueMutex->unlock();
|
|
|
|
// Do the actual decoding
|
|
try {
|
|
entry->decoder->decodeRect(entry->rect, entry->bufferStream->data(),
|
|
entry->bufferStream->length(),
|
|
*entry->cp, entry->pb);
|
|
} catch (rdr::Exception& e) {
|
|
manager->setThreadException(e);
|
|
} catch(...) {
|
|
assert(false);
|
|
}
|
|
|
|
manager->queueMutex->lock();
|
|
|
|
// Remove the entry from the queue and give back the memory buffer
|
|
manager->freeBuffers.push_back(entry->bufferStream);
|
|
manager->workQueue.remove(entry);
|
|
delete entry;
|
|
|
|
// Wake the main thread in case it is waiting for a memory buffer
|
|
manager->producerCond->signal();
|
|
// This rect might have been blocking multiple other rects, so
|
|
// wake up every worker thread
|
|
if (manager->workQueue.size() > 1)
|
|
manager->consumerCond->broadcast();
|
|
}
|
|
|
|
manager->queueMutex->unlock();
|
|
}
|
|
|
|
DecodeManager::QueueEntry* DecodeManager::DecodeThread::findEntry()
|
|
{
|
|
std::list<DecodeManager::QueueEntry*>::iterator iter;
|
|
Region lockedRegion;
|
|
|
|
if (manager->workQueue.empty())
|
|
return NULL;
|
|
|
|
if (!manager->workQueue.front()->active)
|
|
return manager->workQueue.front();
|
|
|
|
for (iter = manager->workQueue.begin();
|
|
iter != manager->workQueue.end();
|
|
++iter) {
|
|
DecodeManager::QueueEntry* entry;
|
|
|
|
std::list<DecodeManager::QueueEntry*>::iterator iter2;
|
|
|
|
entry = *iter;
|
|
|
|
// Another thread working on this?
|
|
if (entry->active)
|
|
goto next;
|
|
|
|
// If this is an ordered decoder then make sure this is the first
|
|
// rectangle in the queue for that decoder
|
|
if (entry->decoder->flags & DecoderOrdered) {
|
|
for (iter2 = manager->workQueue.begin(); iter2 != iter; ++iter2) {
|
|
if (entry->encoding == (*iter2)->encoding)
|
|
goto next;
|
|
}
|
|
}
|
|
|
|
// For a partially ordered decoder we must ask the decoder for each
|
|
// pair of rectangles.
|
|
if (entry->decoder->flags & DecoderPartiallyOrdered) {
|
|
for (iter2 = manager->workQueue.begin(); iter2 != iter; ++iter2) {
|
|
if (entry->encoding != (*iter2)->encoding)
|
|
continue;
|
|
if (entry->decoder->doRectsConflict(entry->rect,
|
|
entry->bufferStream->data(),
|
|
entry->bufferStream->length(),
|
|
(*iter2)->rect,
|
|
(*iter2)->bufferStream->data(),
|
|
(*iter2)->bufferStream->length(),
|
|
*entry->cp))
|
|
goto next;
|
|
}
|
|
}
|
|
|
|
// Check overlap with earlier rectangles
|
|
if (!lockedRegion.intersect(entry->affectedRegion).is_empty())
|
|
goto next;
|
|
|
|
return entry;
|
|
|
|
next:
|
|
lockedRegion.assign_union(entry->affectedRegion);
|
|
}
|
|
|
|
return NULL;
|
|
}
|