opengles emulator: fixed renderer termination flow

Handling clean exit of the renderer when stopOpenGLRenderer
is called. This is done by openning a connection to the renderer
and flag that it should exit. Added 'clientFlags' field which must
be send after every connection is made to the renderer for this purpose.
The server will wait for running rendering threads to exit and then will
close all EGL/GL resources and will exit. The stopOpenGLRenderer will
return only when the renderer has exited.

Change-Id: I8272b8ea59d5fc78453bb7bd2d25908068869fa7

tools/emulator/opengl/host/libs/libOpenglRender/RenderServer.cpp

@@ -16,10 +16,14 @@
 #include "RenderServer.h"
 #include "TcpStream.h"
 #include "RenderThread.h"
+#include "FrameBuffer.h"
+#include <set>
+
+typedef std::set<RenderThread *> RenderThreadsSet;
 
 RenderServer::RenderServer() :
     m_listenSock(NULL),
-    m_exit(false)
+    m_exiting(false)
 {
 }
 
@@ -42,16 +46,26 @@ RenderServer *RenderServer::create(int port)
 
 int RenderServer::Main()
 {
-    while(!m_exit) {
+    RenderThreadsSet threads;
+
+    while(1) {
         TcpStream *stream = m_listenSock->accept();
         if (!stream) {
             fprintf(stderr,"Error accepting connection, aborting\n");
             break;
         }
 
+        unsigned int clientFlags;
+        if (!stream->readFully(&clientFlags, sizeof(unsigned int))) {
+            fprintf(stderr,"Error reading clientFlags\n");
+            delete stream;
+            continue;
+        }
+
         DBG("\n\n\n\n Got new stream!!!! \n\n\n\n\n");
         // check if we have been requested to exit while waiting on accept
-        if (m_exit) {
+        if ((clientFlags & IOSTREAM_CLIENT_EXIT_SERVER) != 0) {
+            m_exiting = true;
             break;
         }
 
@@ -64,10 +78,49 @@ int RenderServer::Main()
         if (!rt->start()) {
             fprintf(stderr,"Failed to start RenderThread\n");
             delete stream;
+            delete rt;
         }
 
+        //
+        // remove from the threads list threads which are
+        // no longer running
+        //
+        for (RenderThreadsSet::iterator n,t = threads.begin();
+             t != threads.end();
+             t = n) {
+            // first find next iterator
+            n = t;
+            n++;
+
+            // delete and erase the current iterator
+            // if thread is no longer running
+            if ((*t)->isFinished()) {
+                delete (*t);
+                threads.erase(t);
+            }
+        }
+
+        // insert the added thread to the list
+        threads.insert(rt);
+
         printf("Started new RenderThread\n");
     }
 
+    //
+    // Wait for all threads to finish
+    //
+    for (RenderThreadsSet::iterator t = threads.begin();
+         t != threads.end();
+         t++) {
+        int exitStatus;
+        (*t)->wait(&exitStatus);
+        delete (*t);
+    }
+    threads.clear();
+
+    //
+    // de-initialize the FrameBuffer object
+    //
+    FrameBuffer::finalize();
     return 0;
 }