(Fdisplay_buffer): Cope with unsplittable frames and dedicated windows.

diff --git a/src/window.c b/src/window.c
index 37266261c74ca55985fbeead126b1bd18b308243..493e2889537764925a52af6b58da417fa0a40fd7 100644 (file)
--- a/src/window.c
+++ b/src/window.c
@@ -1313,6 +1313,7 @@ window_loop (type, obj, mini, frames)
 DEFUN ("get-lru-window", Fget_lru_window, Sget_lru_window, 0, 1, 0,
   "Return the window least recently selected or used for display.\n\
 If optional argument FRAME is `visible', search all visible frames.\n\
+If FRAME is 0, search all visible and iconified frames.\n\
 If FRAME is t, search all frames.\n\
 If FRAME is nil, search only the selected frame.\n\
 If FRAME is a frame, search only that frame.")
@@ -1331,6 +1332,7 @@ If FRAME is a frame, search only that frame.")
 DEFUN ("get-largest-window", Fget_largest_window, Sget_largest_window, 0, 1, 0,
   "Return the largest window in area.\n\
 If optional argument FRAME is `visible', search all visible frames.\n\
+If FRAME is 0, search all visible and iconified frames.\n\
 If FRAME is t, search all frames.\n\
 If FRAME is nil, search only the selected frame.\n\
 If FRAME is a frame, search only that frame.")
@@ -1806,6 +1808,9 @@ Returns the window displaying BUFFER.")
   if (pop_up_windows
 #ifdef MULTI_FRAME
       || FRAME_MINIBUF_ONLY_P (selected_frame)
+      /* If the current frame is a special display frame,
+        don't try to reuse its windows.  */
+      || !NILP (XWINDOW (FRAME_ROOT_WINDOW (selected_frame))->dedicated)
 #endif
       )
     {
@@ -1820,8 +1825,27 @@ Returns the window displaying BUFFER.")
       if (split_height_threshold < window_min_height << 1)
        split_height_threshold = window_min_height << 1;
 
-      window = Fget_largest_window (frames);
+      /* Note that both Fget_largest_window and Fget_lru_window
+        ignore minibuffers and dedicated windows.
+        This means they can return nil.  */
 
+      /* If the frame we would try to split cannot be split,
+        try other frames.  */
+      if (FRAME_NO_SPLIT_P (NILP (frames) ? selected_frame
+                           : last_nonminibuf_frame))
+       {
+         /* Try visible frames first.  */
+         window = Fget_largest_window (Qvisible);
+         /* If that didn't work, try iconified frames.  */
+         if (NILP (window))
+           window = Fget_largest_window (make_number (0));
+         if (NILP (window))
+           window = Fget_largest_window (Qt);
+       }
+      else
+       window = Fget_largest_window (frames);
+
+      /* If we got a tall enough full-width window, split it.  */
       if (!NILP (window)
          && window_height (window) >= split_height_threshold
          && (XFASTINT (XWINDOW (window)->width)
@@ -1830,10 +1854,31 @@ Returns the window displaying BUFFER.")
       else
        {
          window = Fget_lru_window (frames);
-         if ((EQ (window, selected_window)
-              || EQ (XWINDOW (window)->parent, Qnil))
+         /* If the LRU window is selected, and big enough, split it.  */
+         if (!NILP (window)
+             && (EQ (window, selected_window)
+                 || EQ (XWINDOW (window)->parent, Qnil))
              && window_height (window) >= window_min_height << 1)
            window = Fsplit_window (window, Qnil, Qnil);
+#ifdef MULTI_FRAME
+         /* If Fget_lru_window returned nil, try other approaches.  */
+         /* Try visible frames first.  */
+         if (NILP (window))
+           window = Fget_largest_window (Qvisible);
+         /* If that didn't work, try iconified frames.  */
+         if (NILP (window))
+           window = Fget_largest_window (make_number (0));
+         /* Try invisible frames.  */
+         if (NILP (window))
+           window = Fget_largest_window (Qt);
+         /* As a last resort, make a new frame.  */
+         if (NILP (window))
+           window = Fframe_selected_window (call0 (Vpop_up_frame_function));
+#else
+         /* As a last resort, use a non minibuffer window.  */
+         if (NILP (window))
+           window = Fframe_first_window (Fselected_frame ());
+#endif
        }
     }
   else