Only try to build TightPNG stuff when libjpeg is available.

TightPNG replaces the ZLIB stuff int Tight encoding with PNG. It still
uses JPEG rects as well. Theoretically, we could build TightPNG with only
libpng and libjpeg - without zlib - but libpng depends on zlib, so this is
kinda moot.

libvncserver/rfbserver.c

@@ -393,10 +393,8 @@ rfbNewTCPOrUDPClient(rfbScreenInfoPtr rfbScreen,
 
 #if defined(LIBVNCSERVER_HAVE_LIBZ) || defined(LIBVNCSERVER_HAVE_LIBPNG)
       cl->tightQualityLevel = -1;
-#if defined(LIBVNCSERVER_HAVE_LIBJPEG) || defined(LIBVNCSERVER_HAVE_LIBPNG)
-      cl->tightCompressLevel = TIGHT_DEFAULT_COMPRESSION;
-#endif
 #ifdef LIBVNCSERVER_HAVE_LIBJPEG
+      cl->tightCompressLevel = TIGHT_DEFAULT_COMPRESSION;
       cl->turboSubsampLevel = TURBO_DEFAULT_SUBSAMP;
       {
 	int i;
@@ -1983,10 +1981,8 @@ rfbProcessClientNormalMessage(rfbClientPtr cl)
         cl->enableServerIdentity     = FALSE;
 #if defined(LIBVNCSERVER_HAVE_LIBZ) || defined(LIBVNCSERVER_HAVE_LIBPNG)
         cl->tightQualityLevel        = -1;
-#if defined(LIBVNCSERVER_HAVE_LIBJPEG) || defined(LIBVNCSERVER_HAVE_LIBPNG)
-        cl->tightCompressLevel       = TIGHT_DEFAULT_COMPRESSION;
-#endif
 #ifdef LIBVNCSERVER_HAVE_LIBJPEG
+        cl->tightCompressLevel       = TIGHT_DEFAULT_COMPRESSION;
         cl->turboSubsampLevel        = TURBO_DEFAULT_SUBSAMP;
         cl->turboQualityLevel        = -1;
 #endif
@@ -2115,7 +2111,7 @@ rfbProcessClientNormalMessage(rfbClientPtr cl)
 		if ( enc >= (uint32_t)rfbEncodingCompressLevel0 &&
 		     enc <= (uint32_t)rfbEncodingCompressLevel9 ) {
 		    cl->zlibCompressLevel = enc & 0x0F;
-#if defined(LIBVNCSERVER_HAVE_LIBJPEG) || defined(LIBVNCSERVER_HAVE_LIBPNG)
+#ifdef LIBVNCSERVER_HAVE_LIBJPEG
 		    cl->tightCompressLevel = enc & 0x0F;
 		    rfbLog("Using compression level %d for client %s\n",
 			   cl->tightCompressLevel, cl->host);
@@ -2856,7 +2852,7 @@ rfbSendFramebufferUpdate(rfbClientPtr cl,
 	sraRgnReleaseIterator(i); i=NULL;
 #endif
 #endif
-#ifdef LIBVNCSERVER_HAVE_LIBPNG
+#if defined(LIBVNCSERVER_HAVE_LIBJPEG) && defined(LIBVNCSERVER_HAVE_LIBPNG)
     } else if (cl->preferredEncoding == rfbEncodingTightPng) {
 	nUpdateRegionRects = 0;
 
@@ -2988,25 +2984,23 @@ rfbSendFramebufferUpdate(rfbClientPtr cl,
 	    if (!rfbSendRectEncodingZlib(cl, x, y, w, h))
 	        goto updateFailed;
 	    break;
+       case rfbEncodingZRLE:
+       case rfbEncodingZYWRLE:
+           if (!rfbSendRectEncodingZRLE(cl, x, y, w, h))
+	       goto updateFailed;
+           break;
+#endif
 #ifdef LIBVNCSERVER_HAVE_LIBJPEG
 	case rfbEncodingTight:
 	    if (!rfbSendRectEncodingTight(cl, x, y, w, h))
 	        goto updateFailed;
 	    break;
-#endif
-#endif
 #ifdef LIBVNCSERVER_HAVE_LIBPNG
 	case rfbEncodingTightPng:
 	    if (!rfbSendRectEncodingTightPng(cl, x, y, w, h))
 	        goto updateFailed;
 	    break;
 #endif
-#ifdef LIBVNCSERVER_HAVE_LIBZ
-       case rfbEncodingZRLE:
-       case rfbEncodingZYWRLE:
-           if (!rfbSendRectEncodingZRLE(cl, x, y, w, h))
-	       goto updateFailed;
-           break;
 #endif
         }
     }

rfb/rfb.h

@@ -603,8 +603,6 @@ typedef struct _rfbClientRec {
     z_stream zsStruct[4];
     rfbBool zsActive[4];
     int zsLevel[4];
-#endif
-#if defined(LIBVNCSERVER_HAVE_LIBJPEG) || defined(LIBVNCSERVER_HAVE_LIBPNG)
     int tightCompressLevel;
 #endif
 #endif
@@ -880,22 +878,18 @@ extern rfbBool rfbSendRectEncodingUltra(rfbClientPtr cl, int x,int y,int w,int h
 extern rfbBool rfbSendRectEncodingZlib(rfbClientPtr cl, int x, int y, int w,
 				    int h);
 
-#if defined(LIBVNCSERVER_HAVE_LIBJPEG) || defined(LIBVNCSERVER_HAVE_LIBPNG)
+#ifdef LIBVNCSERVER_HAVE_LIBJPEG
 /* tight.c */
 
 #define TIGHT_DEFAULT_COMPRESSION  6
-
-#ifdef LIBVNCSERVER_HAVE_LIBJPEG
 #define TURBO_DEFAULT_SUBSAMP 0
-#endif
 
 extern rfbBool rfbTightDisableGradient;
 
 extern int rfbNumCodedRectsTight(rfbClientPtr cl, int x,int y,int w,int h);
 
-#if defined(LIBVNCSERVER_HAVE_LIBJPEG)
 extern rfbBool rfbSendRectEncodingTight(rfbClientPtr cl, int x,int y,int w,int h);
-#endif
+
 #if defined(LIBVNCSERVER_HAVE_LIBPNG)
 extern rfbBool rfbSendRectEncodingTightPng(rfbClientPtr cl, int x,int y,int w,int h);
 #endif