Use a per-process server address for the GLES server

Previously we used a hardcoded address (tcp port, unix pipe path,
etc.) for the OpenGLRender system. Multiple emulators would all try to
listen on the same address, with the system non-deterministically (?)
choosing which one accepted each new connection. This resulted in
frames going to the wrong emulator window, one emulator shutting down
another's OpenGL system, etc.

Now the OpenGLRender server requests an unused tcp port or derives a
path from the pid, and reports the address back to the emulator client
to use for future connections from the guest.

Change-Id: I6af2eac0c7f27670a3b6595772eebc7aa2b24688

1 files changed, 19 insertions, 4 deletions

diff --git a/emulator/opengl/shared/OpenglCodecCommon/TcpStream.cpp b/emulator/opengl/shared/OpenglCodecCommon/TcpStream.cpp
index 4da2cec..8a6e56e 100644
--- a/emulator/opengl/shared/OpenglCodecCommon/TcpStream.cpp
+++ b/emulator/opengl/shared/OpenglCodecCommon/TcpStream.cpp
@@ -28,6 +28,8 @@
 #include <ws2tcpip.h>
 #endif
 
+#define LISTEN_BACKLOG 4
+
 TcpStream::TcpStream(size_t bufSize) :
     SocketStream(bufSize)
 {
@@ -47,10 +49,22 @@ TcpStream::TcpStream(int sock, size_t bufSize) :
     setsockopt( sock, IPPROTO_TCP, TCP_NODELAY, (const char*)&flag, sizeof(flag) );
 }
 
-int TcpStream::listen(unsigned short port)
+int TcpStream::listen(char addrstr[MAX_ADDRSTR_LEN])
 {
-    m_sock = socket_loopback_server(port, SOCK_STREAM);
-    if (!valid()) return int(ERR_INVALID_SOCKET);
+    m_sock = socket_loopback_server(0, SOCK_STREAM);
+    if (!valid())
+        return int(ERR_INVALID_SOCKET);
+
+    /* get the actual port number assigned by the system */
+    struct sockaddr_in addr;
+    socklen_t addrLen = sizeof(addr);
+    memset(&addr, 0, sizeof(addr));
+    if (getsockname(m_sock, (struct sockaddr*)&addr, &addrLen) < 0) {
+        close(m_sock);
+        return int(ERR_INVALID_SOCKET);
+    }
+    snprintf(addrstr, MAX_ADDRSTR_LEN - 1, "%hu", ntohs(addr.sin_port));
+    addrstr[MAX_ADDRSTR_LEN-1] = '\0';
 
     return 0;
 }
@@ -78,8 +92,9 @@ SocketStream * TcpStream::accept()
     return clientStream;
 }
 
-int TcpStream::connect(unsigned short port)
+int TcpStream::connect(const char* addr)
 {
+    int port = atoi(addr);
     return connect("127.0.0.1",port);
 }