Add a tryScreenLayout function

This can be used to test if a layout if possible.

4 files changed, 141 insertions, 23 deletions

diff --git a/unix/xserver/hw/vnc/RandrGlue.c b/unix/xserver/hw/vnc/RandrGlue.c
index dc8512bd..82e85524 100644
--- a/unix/xserver/hw/vnc/RandrGlue.c
+++ b/unix/xserver/hw/vnc/RandrGlue.c
@@ -49,9 +49,22 @@ int vncGetScreenHeight(void)
   return screenInfo.screens[scrIdx]->height;
 }
 
+int vncRandRIsValidScreenSize(int width, int height)
+{
+  rrScrPrivPtr rp = rrGetScrPriv(screenInfo.screens[scrIdx]);
+
+  if (width < rp->minWidth || rp->maxWidth < width)
+    return 0;
+  if (height < rp->minHeight || rp->maxHeight < height)
+    return 0;
+
+  return 1;
+}
+
 int vncRandRResizeScreen(int width, int height)
 {
   ScreenPtr pScreen = screenInfo.screens[scrIdx];
+
   /* Try to retain DPI when we resize */
   return RRScreenSizeSet(pScreen, width, height,
                          pScreen->mmWidth * width / pScreen->width,
@@ -183,6 +196,44 @@ int vncRandRIsOutputConnected(int outputIdx)
   return (output->connection == RR_Connected);
 }
 
+static RRModePtr vncRandRGetMatchingMode(int outputIdx, int width, int height)
+{
+  rrScrPrivPtr rp = rrGetScrPriv(screenInfo.screens[scrIdx]);
+
+  RROutputPtr output;
+
+  output = rp->outputs[outputIdx];
+
+  if (output->crtc != NULL) {
+    unsigned int swap;
+    switch (output->crtc->rotation) {
+    case RR_Rotate_90:
+    case RR_Rotate_270:
+      swap = width;
+      width = height;
+      height = swap;
+      break;
+    }
+  }
+
+  for (int i = 0; i < output->numModes; i++) {
+    if ((output->modes[i]->mode.width == width) &&
+        (output->modes[i]->mode.height == height))
+      return output->modes[i];
+  }
+
+  return NULL;
+}
+
+int vncRandRCheckOutputMode(int outputIdx, int width, int height)
+{
+  if (vncRandRGetMatchingMode(outputIdx, width, height) != NULL)
+    return 1;
+  if (vncRandRCanCreateModes())
+    return 1;
+  return 0;
+}
+
 int vncRandRDisableOutput(int outputIdx)
 {
   rrScrPrivPtr rp = rrGetScrPriv(screenInfo.screens[scrIdx]);
@@ -284,7 +335,13 @@ int vncRandRReconfigureOutput(int outputIdx, int x, int y,
   }
 
   /* Make sure we have the mode we want */
-  mode = vncRandRCreatePreferredMode(output, width, height);
+  mode = vncRandRGetMatchingMode(outputIdx, width, height);
+  if (mode == NULL) {
+    mode = vncRandRCreateMode(output, width, height);
+    if (mode == NULL)
+      return 0;
+  }
+  mode = vncRandRSetPreferredMode(output, mode);
   if (mode == NULL)
     return 0;
 
@@ -292,6 +349,11 @@ int vncRandRReconfigureOutput(int outputIdx, int x, int y,
   return RRCrtcSet(crtc, mode, x, y, crtc->rotation, 1, &output);
 }
 
+int vncRandRCanCreateOutputs(int extraOutputs)
+{
+  return vncRandRCanCreateScreenOutputs(scrIdx, extraOutputs);
+}
+
 int vncRandRCreateOutputs(int extraOutputs)
 {
   return vncRandRCreateScreenOutputs(scrIdx, extraOutputs);
diff --git a/unix/xserver/hw/vnc/XorgGlue.h b/unix/xserver/hw/vnc/XorgGlue.h
index 68d66686..5d019493 100644
--- a/unix/xserver/hw/vnc/XorgGlue.h
+++ b/unix/xserver/hw/vnc/XorgGlue.h
@@ -48,7 +48,11 @@ int vncGetScreenY(int scrIdx);
 
 // These hide in xvnc.c or vncModule.c
 void vncClientGone(int fd);
+int vncRandRCanCreateScreenOutputs(int scrIdx, int extraOutputs);
 int vncRandRCreateScreenOutputs(int scrIdx, int extraOutputs);
+int vncRandRCanCreateModes(void);
+void* vncRandRCreateMode(void* output, int width, int height);
+void* vncRandRSetPreferredMode(void* output, void* mode);
 
 #ifdef __cplusplus
 }
diff --git a/unix/xserver/hw/vnc/vncModule.c b/unix/xserver/hw/vnc/vncModule.c
index 2a6e73c9..451f527a 100644
--- a/unix/xserver/hw/vnc/vncModule.c
+++ b/unix/xserver/hw/vnc/vncModule.c
@@ -110,28 +110,31 @@ void vncClientGone(int fd)
 {
 }
 
+int vncRandRCanCreateScreenOutputs(int scrIdx, int extraOutputs)
+{
+  return 0;
+}
+
 int vncRandRCreateScreenOutputs(int scrIdx, int extraOutputs)
 {
   return 0;
 }
 
-void *vncRandRCreatePreferredMode(void *out, int width, int height)
+int vncRandRCanCreateModes(void)
+{
+  return 0;
+}
+
+void* vncRandRCreateMode(void* output, int width, int height)
 {
-  RROutputPtr output;
+  return 0;
+}
 
+void* vncRandRSetPreferredMode(void* output, void* mode)
+{
   /*
-   * We're not going to change which modes are preferred, but let's
-   * see if we can at least find a mode with matching dimensions.
+   * We're not going to change which modes are preferred,
+   * so just return the incoming mode.
    */
-
-  output = out;
-
-  for (int i = 0;i < output->numModes;i++) {
-    if ((output->modes[i]->mode.width == width) &&
-        (output->modes[i]->mode.height == height))
-      return output->modes[i];
-  }
-
-  return NULL;
+  return mode;
 }
-
diff --git a/unix/xserver/hw/vnc/xvnc.c b/unix/xserver/hw/vnc/xvnc.c
index f06e0b15..57152cd5 100644
--- a/unix/xserver/hw/vnc/xvnc.c
+++ b/unix/xserver/hw/vnc/xvnc.c
@@ -1377,6 +1377,12 @@ static RRCrtcPtr vncRandRCrtcCreate(ScreenPtr pScreen)
 }
 
 /* Used from XserverDesktop when it needs more outputs... */
+
+int vncRandRCanCreateScreenOutputs(int scrIdx, int extraOutputs)
+{
+    return 1;
+}
+
 int vncRandRCreateScreenOutputs(int scrIdx, int extraOutputs)
 {
     RRCrtcPtr crtc;
@@ -1391,27 +1397,67 @@ int vncRandRCreateScreenOutputs(int scrIdx, int extraOutputs)
     return 1;
 }
 
-/* Used to create a preferred mode from various places */
-void *vncRandRCreatePreferredMode(void *out, int width, int height)
+/* Creating and modifying modes, used by XserverDesktop and init here */
+
+int vncRandRCanCreateModes()
+{
+    return 1;
+}
+
+void* vncRandRCreateMode(void* out, int width, int height)
 {
     RROutputPtr output;
 
     output = out;
 
+    /* Do we already have the mode? */
+    for (int i = 0; i < output->numModes; i++) {
+        if ((output->modes[i]->mode.width == width) &&
+            (output->modes[i]->mode.height == height))
+            return output->modes[i];
+    }
+
+    /* Just recreate the entire list */
+    vncRandRSetModes(output, width, height);
+
+    /* Find the new mode */
+    for (int i = 0; i < output->numModes; i++) {
+        if ((output->modes[i]->mode.width == width) &&
+            (output->modes[i]->mode.height == height))
+            return output->modes[i];
+    }
+
+    /* Something went horribly wrong */
+    return NULL;
+}
+
+void* vncRandRSetPreferredMode(void* out, void* m)
+{
+    RRModePtr mode;
+    RROutputPtr output;
+    int width, height;
+
+    mode = m;
+    output = out;
+
+    width = mode->mode.width;
+    height = mode->mode.height;
+
     /* Already the preferred mode? */
     if ((output->numModes >= 1) && (output->numPreferred == 1) &&
-        (output->modes[0]->mode.width == width) &&
-        (output->modes[0]->mode.height == height))
-        return output->modes[0];
+        (output->modes[0] == mode))
+        return mode;
 
     /* Recreate the list, with the mode we want as preferred */
     vncRandRSetModes(output, width, height);
 
+    /* Sanity check */
     if ((output->numModes >= 1) && (output->numPreferred == 1) &&
         (output->modes[0]->mode.width == width) &&
         (output->modes[0]->mode.height == height))
         return output->modes[0];
 
+    /* Something went horribly wrong */
     return NULL;
 }
 
@@ -1434,8 +1480,11 @@ static Bool vncRandRInit(ScreenPtr pScreen)
     crtc = vncRandRCrtcCreate(pScreen);
 
     /* Make sure the current screen size is the active mode */
-    mode = vncRandRCreatePreferredMode(crtc->outputs[0],
-                                       pScreen->width, pScreen->height);
+    mode = vncRandRCreateMode(crtc->outputs[0],
+                              pScreen->width, pScreen->height);
+    if (mode == NULL)
+        return FALSE;
+    mode = vncRandRSetPreferredMode(crtc->outputs[0], mode);
     if (mode == NULL)
         return FALSE;