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flightgear/src/Network/jpg-httpd.cxx
Torsten Dreyer 390f6dd32d fix wrong computation of delta-t in jpg-httpd
this lead to a screenshot taken on each frame instead of
the defined interval
2014-03-29 11:22:34 +01:00

568 lines
15 KiB
C++

// jpg-httpd.cxx -- FGFS jpg-http interface
//
// Written by Curtis Olson, started June 2001.
//
// Copyright (C) 2001 Curtis L. Olson - http://www.flightgear.org/~curt
//
// Jpeg Image Support added August 2001
// by Norman Vine - nhv@cape.com
//
// 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.
//
// 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
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
//
// $Id$
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <simgear/compiler.h>
#include <cstdlib> // atoi() atof()
#include <cstring>
#include <osgDB/Registry>
#include <osgDB/ReaderWriter>
#include <osgUtil/SceneView>
#include <osgViewer/Viewer>
#include <simgear/debug/logstream.hxx>
#include <simgear/io/iochannel.hxx>
#include <simgear/math/sg_types.hxx>
#include <simgear/props/props.hxx>
#include <simgear/io/sg_netChat.hxx>
#include <simgear/threads/SGThread.hxx>
#include <simgear/threads/SGGuard.hxx>
#include <Main/fg_props.hxx>
#include <Main/globals.hxx>
#include <Viewer/renderer.hxx>
#include "jpg-httpd.hxx"
#define HTTP_GET_STRING "GET "
#define HTTP_TERMINATOR "\r\n"
using std::string;
//////////////////////////////////////////////////////////////
// class CompressedImageBuffer
//////////////////////////////////////////////////////////////
class CompressedImageBuffer : public SGReferenced
{
public:
CompressedImageBuffer(osg::Image* img) :
_image(img)
{
}
bool compress(const std::string& extension)
{
osgDB::ReaderWriter* writer =
osgDB::Registry::instance()->getReaderWriterForExtension(extension);
std::stringstream outputStream;
osgDB::ReaderWriter::WriteResult wr;
wr = writer->writeImage(*_image,outputStream, NULL);
if(wr.success()) {
_compressedData = outputStream.str();
return true;
} else {
return false;
}
}
size_t size() const
{
return _compressedData.length();
}
const char* data() const
{
return _compressedData.data();
}
private:
osg::ref_ptr<osg::Image> _image;
std::string _compressedData;
};
typedef SGSharedPtr<CompressedImageBuffer> ImageBufferPtr;
//////////////////////////////////////////////////////////////
class HttpdThread : public SGThread, private simgear::NetChannel
{
public:
HttpdThread (int port, int frameHz, const std::string& type) :
_done(false),
_port(port),
_hz(frameHz),
_imageType(type)
{
}
bool init();
void shutdown();
virtual void run();
void setNewFrameImage(osg::Image* frameImage)
{
SGGuard<SGMutex> g(_newFrameLock);
_newFrame = frameImage;
}
int getFrameHz() const
{ return _hz; }
void setDone()
{
_done = true;
}
private:
virtual bool writable (void) { return false; }
virtual void handleAccept (void);
bool _done;
simgear::NetChannelPoller _poller;
int _port, _hz;
std::string _imageType;
SGMutex _newFrameLock;
osg::ref_ptr<osg::Image> _newFrame;
/// current frame we're serving to new connections
ImageBufferPtr _currentFrame;
};
///////////////////////////////////////////////////////////////////////////
class WindowCaptureCallback : public osg::Camera::DrawCallback
{
public:
enum Mode
{
READ_PIXELS,
SINGLE_PBO,
DOUBLE_PBO,
TRIPLE_PBO
};
enum FramePosition
{
START_FRAME,
END_FRAME
};
struct ContextData : public osg::Referenced
{
ContextData(osg::GraphicsContext* gc, Mode mode, GLenum readBuffer, HttpdThread* httpd):
_gc(gc),
_mode(mode),
_readBuffer(readBuffer),
_pixelFormat(GL_RGB),
_type(GL_UNSIGNED_BYTE),
_width(0),
_height(0),
_currentImageIndex(0),
_httpd(httpd)
{
_previousFrameTick = osg::Timer::instance()->tick();
if (gc->getTraits() && gc->getTraits()->alpha) {
_pixelFormat = GL_RGBA;
}
getSize(gc, _width, _height);
// single buffered image
_imageBuffer.push_back(new osg::Image);
}
void getSize(osg::GraphicsContext* gc, int& width, int& height)
{
if (gc->getTraits())
{
width = gc->getTraits()->width;
height = gc->getTraits()->height;
}
}
void readPixels();
typedef std::vector< osg::ref_ptr<osg::Image> > ImageBuffer;
osg::GraphicsContext* _gc;
Mode _mode;
GLenum _readBuffer;
GLenum _pixelFormat;
GLenum _type;
int _width;
int _height;
unsigned int _currentImageIndex;
ImageBuffer _imageBuffer;
osg::Timer_t _previousFrameTick;
HttpdThread* _httpd;
};
WindowCaptureCallback(HttpdThread *thread, Mode mode, FramePosition position, GLenum readBuffer):
_mode(mode),
_position(position),
_readBuffer(readBuffer),
_thread(thread)
{
}
FramePosition getFramePosition() const { return _position; }
ContextData* createContextData(osg::GraphicsContext* gc) const
{
return new ContextData(gc, _mode, _readBuffer, _thread);
}
ContextData* getContextData(osg::GraphicsContext* gc) const
{
OpenThreads::ScopedLock<OpenThreads::Mutex> lock(_mutex);
osg::ref_ptr<ContextData>& data = _contextDataMap[gc];
if (!data) data = createContextData(gc);
return data.get();
}
virtual void operator () (osg::RenderInfo& renderInfo) const
{
glReadBuffer(_readBuffer);
osg::GraphicsContext* gc = renderInfo.getState()->getGraphicsContext();
osg::ref_ptr<ContextData> cd = getContextData(gc);
cd->readPixels();
}
typedef std::map<osg::GraphicsContext*, osg::ref_ptr<ContextData> > ContextDataMap;
Mode _mode;
FramePosition _position;
GLenum _readBuffer;
mutable OpenThreads::Mutex _mutex;
mutable ContextDataMap _contextDataMap;
HttpdThread* _thread;
};
void WindowCaptureCallback::ContextData::readPixels()
{
osg::Timer_t n = osg::Timer::instance()->tick();
double dt = osg::Timer::instance()->delta_s(_previousFrameTick,n);
double frameInterval = 1.0 / _httpd->getFrameHz();
if (dt < frameInterval)
return;
_previousFrameTick = n;
unsigned int nextImageIndex = (_currentImageIndex+1)%_imageBuffer.size();
int width=0, height=0;
getSize(_gc, width, height);
if (width!=_width || _height!=height)
{
_width = width;
_height = height;
}
osg::Image* image = _imageBuffer[_currentImageIndex].get();
image->readPixels(0,0,_width,_height,
_pixelFormat,_type);
_httpd->setNewFrameImage(image);
_currentImageIndex = nextImageIndex;
}
osg::Camera* findLastCamera(osgViewer::ViewerBase& viewer)
{
osgViewer::ViewerBase::Windows windows;
viewer.getWindows(windows);
for(osgViewer::ViewerBase::Windows::iterator itr = windows.begin();
itr != windows.end();
++itr)
{
osgViewer::GraphicsWindow* window = *itr;
osg::GraphicsContext::Cameras& cameras = window->getCameras();
osg::Camera* lastCamera = 0;
for(osg::GraphicsContext::Cameras::iterator cam_itr = cameras.begin();
cam_itr != cameras.end();
++cam_itr)
{
if (lastCamera)
{
if ((*cam_itr)->getRenderOrder() > lastCamera->getRenderOrder())
{
lastCamera = (*cam_itr);
}
if ((*cam_itr)->getRenderOrder() == lastCamera->getRenderOrder() &&
(*cam_itr)->getRenderOrderNum() >= lastCamera->getRenderOrderNum())
{
lastCamera = (*cam_itr);
}
}
else
{
lastCamera = *cam_itr;
}
}
return lastCamera;
}
return NULL;
}
//////////////////////////////////////////////////////////////
// class HttpdImageChannel
//////////////////////////////////////////////////////////////
class HttpdImageChannel : public simgear::NetChannel
{
public:
HttpdImageChannel(SGSharedPtr<CompressedImageBuffer> img) :
_imageData(img),
_bytesToSend(0)
{
}
void setMimeType(const std::string& s)
{
_mimeType = s;
}
virtual void collectIncomingData (const char* s, int n)
{
_request += string(s, n);
}
virtual void handleRead()
{
char data[512];
int num_read = recv(data, 512);
if (num_read > 0) {
_request += std::string(data, num_read);
}
if (_request.find(HTTP_TERMINATOR) != std::string::npos) {
// have complete first line of request
if (_request.find(HTTP_GET_STRING) == 0) {
processRequest();
}
}
}
virtual void handleWrite()
{
sendResponse();
}
private:
void processRequest();
void sendResponse();
std::string _request;
ImageBufferPtr _imageData;
std::string _mimeType;
size_t _bytesToSend;
};
//////////////////////////////////////////////////////////////
// class HttpdThread
//////////////////////////////////////////////////////////////
bool HttpdThread::init()
{
if (!open()) {
SG_LOG( SG_IO, SG_ALERT, "Failed to open HttpdImage port.");
return false;
}
if (0 != bind( "", _port )) {
SG_LOG( SG_IO, SG_ALERT, "Failed to bind HttpdImage port.");
return false;
}
if (0 != listen( 5 )) {
SG_LOG( SG_IO, SG_ALERT, "Failed to listen on HttpdImage port.");
return false;
}
_poller.addChannel(this);
osgViewer::Viewer* v = globals->get_renderer()->getViewer();
osg::Camera* c = findLastCamera(*v);
if (!c) {
return false;
}
c->setFinalDrawCallback(new WindowCaptureCallback(this,
WindowCaptureCallback::READ_PIXELS,
WindowCaptureCallback::END_FRAME,
GL_BACK));
SG_LOG(SG_IO, SG_INFO, "HttpdImage server started on port " << _port);
return true;
}
void HttpdThread::shutdown()
{
setDone();
join();
osgViewer::Viewer* v = globals->get_renderer()->getViewer();
osg::Camera* c = findLastCamera(*v);
c->setFinalDrawCallback(NULL);
SG_LOG(SG_IO, SG_INFO, "HttpdImage server shutdown on port " << _port);
}
void HttpdThread::run()
{
while (!_done) {
_poller.poll(10); // 10msec sleep
// locked section to check for a new raw frame from the callback
osg::ref_ptr<osg::Image> frameToWriteOut;
{
SGGuard<SGMutex> g(_newFrameLock);
if (_newFrame) {
frameToWriteOut = _newFrame;
_newFrame = NULL;
}
} // of locked section
// no locking needed on currentFrame; channels run in this thread
if (frameToWriteOut) {
_currentFrame = ImageBufferPtr(new CompressedImageBuffer(frameToWriteOut));
_currentFrame->compress(_imageType);
}
} // of thread poll loop
}
void HttpdThread::handleAccept (void)
{
simgear::IPAddress addr;
int handle = accept ( &addr );
SG_LOG( SG_IO, SG_DEBUG, "Client " << addr.getHost() << ":" << addr.getPort() << " connected" );
HttpdImageChannel *hc = new HttpdImageChannel(_currentFrame);
hc->setMimeType("image/" + _imageType);
hc->setHandle ( handle );
_poller.addChannel( hc );
}
//////////////////////////////////////////////////////////////
// class FGJpegHttpd
//////////////////////////////////////////////////////////////
FGJpegHttpd::FGJpegHttpd( int p, int hz, const std::string& type )
{
_imageServer.reset(new HttpdThread( p, hz, type ));
}
FGJpegHttpd::~FGJpegHttpd()
{
}
bool FGJpegHttpd::open()
{
if ( is_enabled() ) {
SG_LOG( SG_IO, SG_ALERT, "This shouldn't happen, but the channel "
<< "is already in use, ignoring" );
return false;
}
if (!_imageServer->init()) {
SG_LOG( SG_IO, SG_ALERT, "FGJpegHttpd: failed to init Http sevrer thread");
return false;
}
_imageServer->start();
set_enabled( true );
return true;
}
bool FGJpegHttpd::process()
{
return true;
}
bool FGJpegHttpd::close()
{
_imageServer->shutdown();
return true;
}
void HttpdImageChannel::processRequest()
{
std::ostringstream ss;
_bytesToSend = _imageData->size();
if (_bytesToSend <= 0) {
return;
}
// assemble HTTP 1.1 headers. Connection: close is important since we
// don't attempt pipelining at all
ss << "HTTP/1.1 200 OK" << HTTP_TERMINATOR;
ss << "Content-Type: " << _mimeType << HTTP_TERMINATOR;
ss << "Content-Length: " << _bytesToSend << HTTP_TERMINATOR;
ss << "Connection: close" << HTTP_TERMINATOR;
ss << HTTP_TERMINATOR; // end of headers
if( getHandle() == -1 )
{
SG_LOG( SG_IO, SG_DEBUG, "<<<<<<<<< Invalid socket handle. Ignoring request.\n" );
return;
}
// send headers out
string headersData(ss.str());
if (send(headersData.c_str(), headersData.length()) <= 0 )
{
SG_LOG( SG_IO, SG_DEBUG, "<<<<<<<<< Error to send HTTP response. Ignoring request.\n" );
return;
}
_bytesToSend = _imageData->size();
sendResponse();
}
void HttpdImageChannel::sendResponse()
{
const char* ptr = _imageData->data();
ptr += (_imageData->size() - _bytesToSend);
size_t sent = send(ptr, _bytesToSend);
if (sent <= 0) {
SG_LOG( SG_IO, SG_DEBUG, "<<<<<<<<< Error to send HTTP response. Ignoring request.\n" );
return;
}
_bytesToSend -= sent;
if (_bytesToSend == 0) {
close();
shouldDelete(); // use NetChannelPoller delete mechanism
}
}