add libvncserver

[presencevnc] / libvnc / client_examples / backchannel.c

diff --git a/libvnc/client_examples/backchannel.c b/libvnc/client_examples/backchannel.c
new file mode 100644 (file)
index 0000000..643754e
--- /dev/null
+++ b/libvnc/client_examples/backchannel.c
@@ -0,0 +1,99 @@
+/* A simple example of an RFB client */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include <errno.h>
+#include <rfb/rfbclient.h>
+
+static void HandleRect(rfbClient* client, int x, int y, int w, int h) {
+}
+
+/*
+ * The client part of the back channel extension example.
+ *
+ */
+
+#define rfbBackChannel 155
+
+typedef struct backChannelMsg {
+        uint8_t type;
+        uint8_t pad1;
+        uint16_t pad2;
+        uint32_t size;
+} backChannelMsg;
+
+static void sendMessage(rfbClient* client, char* text)
+{
+       backChannelMsg msg;
+       uint32_t length = strlen(text)+1;
+
+       msg.type = rfbBackChannel;
+       msg.size = rfbClientSwap32IfLE(length);
+       if(!WriteToRFBServer(client, (char*)&msg, sizeof(msg)) ||
+                       !WriteToRFBServer(client, text, length)) {
+               rfbClientLog("enableBackChannel: write error (%d: %s)", errno, strerror(errno));
+       }
+}
+
+static rfbBool handleBackChannelMessage(rfbClient* client,
+       rfbServerToClientMsg* message)
+{
+       backChannelMsg msg;
+       char* text;
+
+       if(message->type != rfbBackChannel)
+               return FALSE;
+
+       rfbClientSetClientData(client, sendMessage, sendMessage);
+
+       if(!ReadFromRFBServer(client, ((char*)&msg)+1, sizeof(msg)-1))
+               return TRUE;
+       msg.size = rfbClientSwap32IfLE(msg.size);
+       text = malloc(msg.size);
+       if(!ReadFromRFBServer(client, text, msg.size)) {
+               free(text);
+               return TRUE;
+       }
+
+       rfbClientLog("got back channel message: %s\n", text);
+       free(text);
+
+       return TRUE;
+}
+
+static int backChannelEncodings[] = { rfbBackChannel, 0 };
+
+static rfbClientProtocolExtension backChannel = {
+       backChannelEncodings,           /* encodings */
+       NULL,                           /* handleEncoding */
+       handleBackChannelMessage,       /* handleMessage */
+       NULL                            /* next extension */
+};
+
+int
+main(int argc, char **argv)
+{
+       rfbClient* client = rfbGetClient(8,3,4);
+
+       client->GotFrameBufferUpdate = HandleRect;
+       rfbClientRegisterExtension(&backChannel);
+
+       if (!rfbInitClient(client,&argc,argv))
+               return 1;
+
+       while (1) {
+               /* After each idle second, send a message */
+               if(WaitForMessage(client,1000000)>0)
+                       HandleRFBServerMessage(client);
+               else if(rfbClientGetClientData(client, sendMessage))
+                       sendMessage(client, "Dear Server,\n"
+                                       "thank you for understanding "
+                                       "back channel messages!");
+       }
+
+       rfbClientCleanup(client);
+
+       return 0;
+}
+