size_t is unsigned, change to ssize_t to handle errors from tight_compress_data()

Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>

ui/vnc-enc-tight.c

diff --git a/ui/vnc-enc-tight.c b/ui/vnc-enc-tight.c
index c4c9c3b..c942bb7 100644
--- a/ui/vnc-enc-tight.c
+++ b/ui/vnc-enc-tight.c
@@ -905,7 +905,7 @@
 static int send_full_color_rect(VncState *vs, int x, int y, int w, int h)
 {
     int stream = 0;
-    size_t bytes;
+    ssize_t bytes;
 
 #ifdef CONFIG_VNC_PNG
     if (tight_can_send_png_rect(vs, w, h)) {
@@ -949,7 +949,7 @@
 static int send_mono_rect(VncState *vs, int x, int y,
                           int w, int h, uint32_t bg, uint32_t fg)
 {
-    size_t bytes;
+    ssize_t bytes;
     int stream = 1;
     int level = tight_conf[vs->tight.compression].mono_zlib_level;
 
@@ -1029,7 +1029,7 @@
 {
     int stream = 3;
     int level = tight_conf[vs->tight.compression].gradient_zlib_level;
-    size_t bytes;
+    ssize_t bytes;
 
     if (vs->clientds.pf.bytes_per_pixel == 1)
         return send_full_color_rect(vs, x, y, w, h);
@@ -1066,7 +1066,7 @@
     int stream = 2;
     int level = tight_conf[vs->tight.compression].idx_zlib_level;
     int colors;
-    size_t bytes;
+    ssize_t bytes;
 
 #ifdef CONFIG_VNC_PNG
     if (tight_can_send_png_rect(vs, w, h)) {