Server Capability Encodings

rfbEncodingSupportedEncodings - What encodings are supported?
rfbEncodingSupportedMessages  - What message types are supported?
rfbEncodingServerIdentity     - What is the servers version string?
ie: "x11vnc: 0.8.1 lastmod: 2006-04-25 (LibVNCServer 0.9pre)"

ChangeLog

+2006-05-04  Steven Carr <scarr@jsa-usa.com>
+	* rfbEncodingSupportedEncodings - What encodings are supported?
+	* rfbEncodingSupportedMessages - What message types are supported?
+	  This way a client can identify if a particular server supports a
+	  specific message types.
+	* rfbEncodingServerIdentity - What is the servers version string?
+	  ie: "x11vnc: 0.8.1 lastmod: 2006-04-25 (LibVNCServer 0.9pre)"
+
 2006-05-03  Steven Carr <scarr@jsa-usa.com>
 	* Server Side Scaling is now supported in libvncserver
 	  Both PalmVNC and UltraVNC SetScale messages are supported

libvncclient/rfbproto.c

@@ -532,25 +532,6 @@ SetFormatAndEncodings(rfbClient* client)
       encs[se->nEncodings++] = rfbClientSwap32IfLE(client->appData.qualityLevel +
 					  rfbEncodingQualityLevel0);
     }
-
-
-    if (client->appData.useRemoteCursor) {
-      if (se->nEncodings < MAX_ENCODINGS)
-	encs[se->nEncodings++] = rfbClientSwap32IfLE(rfbEncodingXCursor);
-      if (se->nEncodings < MAX_ENCODINGS)
-	encs[se->nEncodings++] = rfbClientSwap32IfLE(rfbEncodingRichCursor);
-      if (se->nEncodings < MAX_ENCODINGS)
-	encs[se->nEncodings++] = rfbClientSwap32IfLE(rfbEncodingPointerPos);
-    }
-
-    /* Let's receive keyboard state encoding if available */
-    if (se->nEncodings < MAX_ENCODINGS) {
-        encs[se->nEncodings++] = rfbClientSwap32IfLE(rfbEncodingKeyboardLedState);
-    }
-
-    if (se->nEncodings < MAX_ENCODINGS && requestLastRectEncoding) {
-      encs[se->nEncodings++] = rfbClientSwap32IfLE(rfbEncodingLastRect);
-    }
   }
   else {
     if (SameMachine(client->sock)) {
@@ -570,6 +551,7 @@ SetFormatAndEncodings(rfbClient* client)
 #ifdef LIBVNCSERVER_HAVE_LIBZ
 #ifdef LIBVNCSERVER_HAVE_LIBJPEG
     encs[se->nEncodings++] = rfbClientSwap32IfLE(rfbEncodingTight);
+    requestLastRectEncoding = TRUE;
 #endif
 #endif
     encs[se->nEncodings++] = rfbClientSwap32IfLE(rfbEncodingHextile);
@@ -599,24 +581,42 @@ SetFormatAndEncodings(rfbClient* client)
       encs[se->nEncodings++] = rfbClientSwap32IfLE(client->appData.qualityLevel +
 					  rfbEncodingQualityLevel0);
     }
+  }
 
-    if (client->appData.useRemoteCursor) {
+
+
+  /* Remote Cursor Support (local to viewer) */
+  if (client->appData.useRemoteCursor) {
+    if (se->nEncodings < MAX_ENCODINGS)
       encs[se->nEncodings++] = rfbClientSwap32IfLE(rfbEncodingXCursor);
+    if (se->nEncodings < MAX_ENCODINGS)
       encs[se->nEncodings++] = rfbClientSwap32IfLE(rfbEncodingRichCursor);
-      encs[se->nEncodings++] = rfbClientSwap32IfLE(rfbEncodingPointerPos);
-    }
-
     if (se->nEncodings < MAX_ENCODINGS)
-      encs[se->nEncodings++] = rfbClientSwap32IfLE(rfbEncodingLastRect);
+      encs[se->nEncodings++] = rfbClientSwap32IfLE(rfbEncodingPointerPos);
   }
 
   /* Keyboard State Encodings */
   if (se->nEncodings < MAX_ENCODINGS)
     encs[se->nEncodings++] = rfbClientSwap32IfLE(rfbEncodingKeyboardLedState);
 
+  /* New Frame Buffer Size */
   if (se->nEncodings < MAX_ENCODINGS && client->canHandleNewFBSize)
     encs[se->nEncodings++] = rfbClientSwap32IfLE(rfbEncodingNewFBSize);
 
+  /* Last Rect */
+  if (se->nEncodings < MAX_ENCODINGS && requestLastRectEncoding)
+    encs[se->nEncodings++] = rfbClientSwap32IfLE(rfbEncodingLastRect);
+
+  /* Server Capabilities */
+  if (se->nEncodings < MAX_ENCODINGS)
+    encs[se->nEncodings++] = rfbClientSwap32IfLE(rfbEncodingSupportedMessages);
+  if (se->nEncodings < MAX_ENCODINGS)
+    encs[se->nEncodings++] = rfbClientSwap32IfLE(rfbEncodingSupportedEncodings);
+  if (se->nEncodings < MAX_ENCODINGS)
+    encs[se->nEncodings++] = rfbClientSwap32IfLE(rfbEncodingServerIdentity);
+
+
+  /* client extensions */
   for(e = rfbClientExtensions; e; e = e->next)
     if(e->encodings) {
       int* enc;
@@ -856,6 +856,65 @@ HandleRFBServerMessage(rfbClient* client)
 	continue;
       }
 
+      /* rect.r.w=byte count */
+      if (rect.encoding == rfbEncodingSupportedMessages) {
+          rfbSupportedMessages msgs;
+          int loop;
+          if (!ReadFromRFBServer(client, (char *)&msgs, sz_rfbSupportedMessages))
+              return FALSE;
+
+          /* msgs is two sets of bit flags of supported messages client2server[] and server2client[] */
+          /* currently ignored by this library */
+
+          rfbClientLog("client2server supported messages (bit flags)\n");
+          for (loop=0;loop<32;loop+=8)
+            rfbClientLog("%02X: %04x %04x %04x %04x - %04x %04x %04x %04x\n", loop,
+                msgs.client2server[loop],   msgs.client2server[loop+1],
+                msgs.client2server[loop+2], msgs.client2server[loop+3],
+                msgs.client2server[loop+4], msgs.client2server[loop+5],
+                msgs.client2server[loop+6], msgs.client2server[loop+7]);
+
+          rfbClientLog("server2client supported messages (bit flags)\n");
+          for (loop=0;loop<32;loop+=8)
+            rfbClientLog("%02X: %04x %04x %04x %04x - %04x %04x %04x %04x\n", loop,
+                msgs.server2client[loop],   msgs.server2client[loop+1],
+                msgs.server2client[loop+2], msgs.server2client[loop+3],
+                msgs.server2client[loop+4], msgs.server2client[loop+5],
+                msgs.server2client[loop+6], msgs.server2client[loop+7]);
+          continue;
+      }
+
+      /* rect.r.w=byte count, rect.r.h=# of encodings */
+      if (rect.encoding == rfbEncodingSupportedEncodings) {
+          char *buffer;
+          buffer = malloc(rect.r.w);
+          if (!ReadFromRFBServer(client, buffer, rect.r.w))
+          {
+              free(buffer);
+              return FALSE;
+          }
+
+          /* buffer now contains rect.r.h # of uint32_t encodings that the server supports */
+          /* currently ignored by this library */
+          free(buffer);
+          continue;
+      }
+
+      /* rect.r.w=byte count */
+      if (rect.encoding == rfbEncodingServerIdentity) {
+          char *buffer;
+          buffer = malloc(rect.r.w+1);
+          if (!ReadFromRFBServer(client, buffer, rect.r.w))
+          {
+              free(buffer);
+              return FALSE;
+          }
+          buffer[rect.r.w]=0; /* null terminate, just in case */
+          rfbClientLog("Connected to Server \"%s\"\n", buffer);
+          free(buffer);
+          continue;
+      }
+
       /* rfbEncodingUltraZip is a collection of subrects.   x = # of subrects, and h is always 0 */
       if (rect.encoding != rfbEncodingUltraZip)
       {

rfb/rfb.h

@@ -323,6 +323,9 @@ typedef struct _rfbScreenInfo
 
     /* handle as many input events as possible (default off) */
     rfbBool handleEventsEagerly;
+
+    /* rfbEncodingServerIdentity */
+    char *versionString;
 } rfbScreenInfo, *rfbScreenInfoPtr;
 
 
@@ -501,6 +504,9 @@ typedef struct _rfbClientRec {
 
 
     int     lastKeyboardLedState;     /* keep track of last value so we can send *change* events */
+    rfbBool enableSupportedMessages;  /* client supports SupportedMessages encoding */
+    rfbBool enableSupportedEncodings; /* client supports SupportedEncodings encoding */
+    rfbBool enableServerIdentity;     /* client supports ServerIdentity encoding */
     rfbBool enableKeyboardLedState;   /* client supports KeyboardState encoding */
     rfbBool enableLastRectEncoding;   /* client supports LastRect encoding */
     rfbBool enableCursorShapeUpdates; /* client supports cursor shape updates */
@@ -852,6 +858,7 @@ extern void rfbNewFramebuffer(rfbScreenInfoPtr rfbScreen,char *framebuffer,
  int bytesPerPixel);
 
 extern void rfbScreenCleanup(rfbScreenInfoPtr screenInfo);
+extern void rfbSetServerVersionIdentity(rfbScreenInfoPtr screen, char *fmt, ...);
 
 /* functions to accept/refuse a client that has been put on hold
    by a NewClientHookPtr function. Must not be called in other

rfb/rfbproto.h

@@ -401,8 +401,8 @@ typedef struct {
 #define rfbEncodingZlib 6
 #define rfbEncodingTight 7
 #define rfbEncodingZlibHex 8
-#define rfbEncodingUltra 9
 #endif
+#define rfbEncodingUltra 9
 #ifdef LIBVNCSERVER_HAVE_LIBZ
 #define rfbEncodingZRLE 16
 #endif
@@ -446,9 +446,12 @@ typedef struct {
 #define rfbEncodingRichCursor      0xFFFFFF11
 #define rfbEncodingPointerPos      0xFFFFFF18
 
-#define rfbEncodingLastRect        0xFFFFFF20
-#define rfbEncodingNewFBSize       0xFFFFFF21
-#define rfbEncodingKeyboardLedState 0xFFFFFF22
+#define rfbEncodingLastRect           0xFFFFFF20
+#define rfbEncodingNewFBSize          0xFFFFFF21
+#define rfbEncodingKeyboardLedState   0xFFFFFF22
+#define rfbEncodingSupportedMessages  0xFFFFFF23
+#define rfbEncodingSupportedEncodings 0xFFFFFF24
+#define rfbEncodingServerIdentity     0xFFFFFF25
 
 #define rfbEncodingQualityLevel0   0xFFFFFFE0
 #define rfbEncodingQualityLevel1   0xFFFFFFE1
@@ -514,6 +517,34 @@ typedef struct {
 
 #define sz_rfbFramebufferUpdateRectHeader (sz_rfbRectangle + 4)
 
+/*- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+ * Supported Messages Encoding.  This encoding does not contain any pixel data.
+ * Instead, it contains 2 sets of bitflags.  These bitflags indicate what messages
+ * are supported by the server.
+ * rect->w contains byte count
+ */
+
+typedef struct {
+  uint8_t client2server[32]; /* maximum of 256 message types (256/8)=32 */
+  uint8_t server2client[32]; /* maximum of 256 message types (256/8)=32 */
+} rfbSupportedMessages;
+
+#define sz_rfbSupportedMessages 64
+
+/*- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+ * Supported Encodings Encoding.  This encoding does not contain any pixel data.
+ * Instead, it contains a list of (uint32_t) Encodings supported by this server.
+ * rect->w contains byte count
+ * rect->h contains encoding count
+ */
+
+/*- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+ * Server Identity Encoding.  This encoding does not contain any pixel data.
+ * Instead, it contains a text string containing information about the server.
+ * ie: "x11vnc: 0.8.1 lastmod: 2006-04-25 (libvncserver 0.9pre)\0"
+ * rect->w contains byte count
+ */
+
 
 /*- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  * Raw Encoding.  Pixels are sent in top-to-bottom scanline order,
@@ -1244,7 +1275,7 @@ typedef struct _rfbSetScaleMsg {
  * client buffer.
  */
 typedef struct {
-    uint8_t type;			/* always rfbSetScaleFactor */
+    uint8_t type;			/* always rfbPalmVNCSetScaleFactor */
 
     uint8_t scale;		/* Scale factor (positive non-zero integer) */
     uint16_t pad2;

x11vnc/screen.c

@@ -1966,6 +1966,8 @@ void initialize_screen(int *argc, char **argv, XImage *fb) {
 		screen->deferUpdateTime = defer_update;
 	}
 
+	rfbSetServerVersionIdentity(screen, "x11vnc: %s", lastmod);
+
 	rfbInitServer(screen);
 
 	if (use_openssl) {