ui: refactor code for determining if an update should be sent to the client

[mirror_qemu.git] / ui / vnc.c

diff --git a/ui/vnc.c b/ui/vnc.c
index 869c75bbcfac6f0e9e21c713d2321a60db12b1ab..6ae002cd36157557cabb8c7c9e3f7c4989fae836 100644 (file)
--- a/ui/vnc.c
+++ b/ui/vnc.c
@@ -961,76 +961,92 @@ static int find_and_clear_dirty_height(VncState *vs,
     return h;
 }
 
+static bool vnc_should_update(VncState *vs)
+{
+    switch (vs->update) {
+    case VNC_STATE_UPDATE_NONE:
+        break;
+    case VNC_STATE_UPDATE_INCREMENTAL:
+        /* Only allow incremental updates if the output buffer
+         * is empty, or if audio capture is enabled.
+         */
+        if (!vs->output.offset || vs->audio_cap) {
+            return true;
+        }
+        break;
+    case VNC_STATE_UPDATE_FORCE:
+        return true;
+    }
+    return false;
+}
+
 static int vnc_update_client(VncState *vs, int has_dirty)
 {
+    VncDisplay *vd = vs->vd;
+    VncJob *job;
+    int y;
+    int height, width;
+    int n = 0;
+
     if (vs->disconnecting) {
         vnc_disconnect_finish(vs);
         return 0;
     }
 
     vs->has_dirty += has_dirty;
-    if (vs->need_update) {
-        VncDisplay *vd = vs->vd;
-        VncJob *job;
-        int y;
-        int height, width;
-        int n = 0;
-
-        if (vs->output.offset && !vs->audio_cap && !vs->force_update)
-            /* kernel send buffers are full -> drop frames to throttle */
-            return 0;
+    if (!vnc_should_update(vs)) {
+        return 0;
+    }
 
-        if (!vs->has_dirty && !vs->audio_cap && !vs->force_update)
-            return 0;
+    if (!vs->has_dirty && vs->update != VNC_STATE_UPDATE_FORCE) {
+        return 0;
+    }
 
-        /*
-         * Send screen updates to the vnc client using the server
-         * surface and server dirty map.  guest surface updates
-         * happening in parallel don't disturb us, the next pass will
-         * send them to the client.
-         */
-        job = vnc_job_new(vs);
-
-        height = pixman_image_get_height(vd->server);
-        width = pixman_image_get_width(vd->server);
-
-        y = 0;
-        for (;;) {
-            int x, h;
-            unsigned long x2;
-            unsigned long offset = find_next_bit((unsigned long *) &vs->dirty,
-                                                 height * VNC_DIRTY_BPL(vs),
-                                                 y * VNC_DIRTY_BPL(vs));
-            if (offset == height * VNC_DIRTY_BPL(vs)) {
-                /* no more dirty bits */
+    /*
+     * Send screen updates to the vnc client using the server
+     * surface and server dirty map.  guest surface updates
+     * happening in parallel don't disturb us, the next pass will
+     * send them to the client.
+     */
+    job = vnc_job_new(vs);
+
+    height = pixman_image_get_height(vd->server);
+    width = pixman_image_get_width(vd->server);
+
+    y = 0;
+    for (;;) {
+        int x, h;
+        unsigned long x2;
+        unsigned long offset = find_next_bit((unsigned long *) &vs->dirty,
+                                             height * VNC_DIRTY_BPL(vs),
+                                             y * VNC_DIRTY_BPL(vs));
+        if (offset == height * VNC_DIRTY_BPL(vs)) {
+            /* no more dirty bits */
+            break;
+        }
+        y = offset / VNC_DIRTY_BPL(vs);
+        x = offset % VNC_DIRTY_BPL(vs);
+        x2 = find_next_zero_bit((unsigned long *) &vs->dirty[y],
+                                VNC_DIRTY_BPL(vs), x);
+        bitmap_clear(vs->dirty[y], x, x2 - x);
+        h = find_and_clear_dirty_height(vs, y, x, x2, height);
+        x2 = MIN(x2, width / VNC_DIRTY_PIXELS_PER_BIT);
+        if (x2 > x) {
+            n += vnc_job_add_rect(job, x * VNC_DIRTY_PIXELS_PER_BIT, y,
+                                  (x2 - x) * VNC_DIRTY_PIXELS_PER_BIT, h);
+        }
+        if (!x && x2 == width / VNC_DIRTY_PIXELS_PER_BIT) {
+            y += h;
+            if (y == height) {
                 break;
             }
-            y = offset / VNC_DIRTY_BPL(vs);
-            x = offset % VNC_DIRTY_BPL(vs);
-            x2 = find_next_zero_bit((unsigned long *) &vs->dirty[y],
-                                    VNC_DIRTY_BPL(vs), x);
-            bitmap_clear(vs->dirty[y], x, x2 - x);
-            h = find_and_clear_dirty_height(vs, y, x, x2, height);
-            x2 = MIN(x2, width / VNC_DIRTY_PIXELS_PER_BIT);
-            if (x2 > x) {
-                n += vnc_job_add_rect(job, x * VNC_DIRTY_PIXELS_PER_BIT, y,
-                                      (x2 - x) * VNC_DIRTY_PIXELS_PER_BIT, h);
-            }
-            if (!x && x2 == width / VNC_DIRTY_PIXELS_PER_BIT) {
-                y += h;
-                if (y == height) {
-                    break;
-                }
-            }
         }
-
-        vnc_job_push(job);
-        vs->force_update = 0;
-        vs->has_dirty = 0;
-        return n;
     }
 
-    return 0;
+    vnc_job_push(job);
+    vs->update = VNC_STATE_UPDATE_NONE;
+    vs->has_dirty = 0;
+    return n;
 }
 
 /* audio */
@@ -1867,14 +1883,14 @@ static void ext_key_event(VncState *vs, int down,
 static void framebuffer_update_request(VncState *vs, int incremental,
                                        int x, int y, int w, int h)
 {
-    vs->need_update = 1;
-
     if (incremental) {
-        return;
+        if (vs->update != VNC_STATE_UPDATE_FORCE) {
+            vs->update = VNC_STATE_UPDATE_INCREMENTAL;
+        }
+    } else {
+        vs->update = VNC_STATE_UPDATE_FORCE;
+        vnc_set_area_dirty(vs->dirty, vs->vd, x, y, w, h);
     }
-
-    vs->force_update = 1;
-    vnc_set_area_dirty(vs->dirty, vs->vd, x, y, w, h);
 }
 
 static void send_ext_key_event_ack(VncState *vs)