Merge from trunk.

10 files changed, 1210 insertions, 1846 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 1222c04d091..fa9ed02614a 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,4 +1,4 @@
-2011-06-09  Paul Eggert  <eggert@cs.ucla.edu>
+2011-06-10  Paul Eggert  <eggert@cs.ucla.edu>
 
         * xmenu.c (dialog_selection_callback) [!USE_GTK]: Cast to intptr_t,
         not to EMACS_INT, to avoid GCC warning.
@@ -14,8 +14,6 @@
 
         * data.c (Qcompiled_function): Now static.
 
-2011-06-08  Paul Eggert  <eggert@cs.ucla.edu>
-
         * window.c (window_body_lines): Now static.
 
         * image.c (gif_load): Rename local to avoid shadowing.
@@ -72,6 +70,111 @@
 
         * alloc.c (Fmake_string): Check for out-of-range init.
 
+2011-06-10  Chong Yidong  <cyd@stupidchicken.com>
+
+        * image.c (gif_load): Fix omitted cast error introduced by
+        2011-06-06 change.
+
+2011-06-10  Martin Rudalics  <rudalics@gmx.at>
+
+        * window.h (resize_proportionally, orig_total_lines)
+        (orig_top_line): Remove from window structure.
+        (set_window_height, set_window_width, change_window_heights)
+        (Fdelete_window): Remove prototypes.
+        (resize_frame_windows): Remove duplicate declaration.
+
+2011-06-10  Eli Zaretskii  <eliz@gnu.org>
+
+        * window.h (resize_frame_windows, resize_window_check)
+        (delete_deletable_window, resize_root_window)
+        (resize_frame_windows): Declare prototypes.
+
+        * window.c (resize_window_apply): Make definition be "static" to
+        match the prototype.
+
+2011-06-10  Martin Rudalics  <rudalics@gmx.at>
+
+        * window.c: Remove declarations of Qwindow_size_fixed,
+        window_min_size_1, window_min_size_2, window_min_size,
+        size_window, window_fixed_size_p, enlarge_window, delete_window.
+        Remove static from declaration of Qdelete_window, it's
+        temporarily needed by Fbury_buffer.
+        (replace_window): Don't assign orig_top_line and
+        orig_total_lines.
+        (Fdelete_window, delete_window): Remove.  Window deletion is
+        handled by window.el.
+        (window_loop): Remove DELETE_OTHER_WINDOWS case.  Replace
+        Fdelete_window calls with calls to Qdelete_window.
+        (Fdelete_other_windows): Remove.  Deleting other windows is
+        handled by window.el.
+        (window_fixed_size_p): Remove.  Fixed-sizeness of windows is
+        handled in window.el.
+        (window_min_size_2, window_min_size_1, window_min_size): Remove.
+        Window minimum sizes are handled in window.el.
+        (shrink_windows, size_window, set_window_height)
+        (set_window_width, change_window_heights, window_height)
+        (window_width, CURBEG, CURSIZE, enlarge_window)
+        (adjust_window_trailing_edge, Fadjust_window_trailing_edge)
+        (Fenlarge_window, Fshrink_window): Remove.  Window resizing is
+        handled in window.el.
+        (make_dummy_parent): Rename to make_parent_window and give it a
+        second argument horflag.
+        (make_window): Don't set resize_proportionally any more.
+        (Fsplit_window): Remove.  Windows are split in window.el.
+        (save_restore_action, save_restore_orig_size)
+        (shrink_window_lowest_first, save_restore_orig_size): Remove.
+        Resize mini windows in window.el.
+        (grow_mini_window, shrink_mini_window): Implement by calling
+        Qresize_root_window_vertically, resize_window_check and
+        resize_window_apply.
+        (saved_window, Fset_window_configuration, save_window_save): Do
+        not handle orig_top_line, orig_total_lines, and
+        resize_proportionally.
+        (window_min_height, window_min_width): Move to window.el.
+        (keys_of_window): Move bindings for delete-other-windows,
+        split-window, delete-window and enlarge-window to window.el.
+
+        * buffer.c: Temporarily extern Qdelete_window.
+        (Fbury_buffer): Temporarily call Qdelete_window instead of
+        Fdelete_window (Fbury_buffer will move to window.el soon).
+
+        * frame.c (set_menu_bar_lines_1): Remove code handling
+        orig_top_line and orig_total_lines.
+
+        * dispnew.c (adjust_frame_glyphs_initially): Don't use
+        set_window_height but set heights directly.
+        (change_frame_size_1): Use resize_frame_windows.
+
+        * xdisp.c (init_xdisp): Don't use set_window_height but set
+        heights directly.
+
+        * xfns.c (x_set_menu_bar_lines, x_set_tool_bar_lines): Use
+        resize_frame_windows instead of change_window_heights and run
+        run_window_configuration_change_hook.
+
+        * w32fns.c (x_set_tool_bar_lines): Use resize_frame_windows
+        instead of change_window_heights and run
+        run_window_configuration_change_hook.
+
+2011-06-09  Martin Rudalics  <rudalics@gmx.at>
+
+        * window.c (replace_window): Rename second argument REPLACEMENT to
+        NEW.  New third argument SETFLAG.  Rewrite.
+        (delete_window, make_dummy_parent): Call replace_window with
+        third argument 1.
+        (window_list_1): Move down in code.
+        (run_window_configuration_change_hook): Move set_buffer part
+        before select_frame_norecord part in order to unwind correctly.
+        Rename count1 to count.
+        (recombine_windows, delete_deletable_window, resize_root_window)
+        (Fdelete_other_windows_internal)
+        (Frun_window_configuration_change_hook, make_parent_window)
+        (resize_window_check, resize_window_apply, Fresize_window_apply)
+        (resize_frame_windows, Fsplit_window_internal)
+        (Fdelete_window_internal, Fresize_mini_window_internal): New
+        functions.
+        (syms_of_window): New variables Vwindow_splits and Vwindow_nest.
+
 2011-06-08  Martin Rudalics  <rudalics@gmx.at>
 
         * window.h (window): Add some new members to window structure -
diff --git a/src/buffer.c b/src/buffer.c
index 8fdd094a20d..0c4cdb544a5 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -1938,6 +1938,8 @@ DEFUN ("barf-if-buffer-read-only", Fbarf_if_buffer_read_only,
   return Qnil;
 }
 
+extern Lisp_Object Qdelete_window;
+
 DEFUN ("bury-buffer", Fbury_buffer, Sbury_buffer, 0, 1, "",
        doc: /* Put BUFFER-OR-NAME at the end of the list of all buffers.
 There it is the least likely candidate for `other-buffer' to return;
@@ -1969,7 +1971,7 @@ its frame, iconify that frame.  */)
           else if (NILP (XWINDOW (selected_window)->parent))
             Ficonify_frame (Fwindow_frame (selected_window));
           else
-            Fdelete_window (selected_window);
+            call1 (Qdelete_window, selected_window);
         }
     }
   else
diff --git a/src/dispnew.c b/src/dispnew.c
index 501dc4ffd80..2dffc0dce25 100644
--- a/src/dispnew.c
+++ b/src/dispnew.c
@@ -1933,13 +1933,13 @@ adjust_frame_glyphs_initially (void)
 
   /* Do it for the root window.  */
   XSETFASTINT (root->top_line, top_margin);
+  XSETFASTINT (root->total_lines, frame_lines - 1 - top_margin);
   XSETFASTINT (root->total_cols, frame_cols);
-  set_window_height (sf->root_window, frame_lines - 1 - top_margin, 0);
 
   /* Do it for the mini-buffer window.  */
   XSETFASTINT (mini->top_line, frame_lines - 1);
+  XSETFASTINT (mini->total_lines, 1);
   XSETFASTINT (mini->total_cols, frame_cols);
-  set_window_height (root->next, 1, 0);
 
   adjust_frame_glyphs (sf);
   glyphs_initialized_initially_p = 1;
@@ -5715,24 +5715,7 @@ change_frame_size_1 (register struct frame *f, int newheight, int newwidth, int
 
   if (newheight != FRAME_LINES (f))
     {
-      if (FRAME_HAS_MINIBUF_P (f) && !FRAME_MINIBUF_ONLY_P (f))
-        {
-          /* Frame has both root and mini-buffer.  */
-          XSETFASTINT (XWINDOW (FRAME_ROOT_WINDOW (f))->top_line,
-                       FRAME_TOP_MARGIN (f));
-          set_window_height (FRAME_ROOT_WINDOW (f),
-                             (newheight
-                              - 1
-                              - FRAME_TOP_MARGIN (f)),
-                             2);
-          XSETFASTINT (XWINDOW (FRAME_MINIBUF_WINDOW (f))->top_line,
-                       newheight - 1);
-          set_window_height (FRAME_MINIBUF_WINDOW (f), 1, 0);
-        }
-      else
-        /* Frame has just one top-level window.  */
-        set_window_height (FRAME_ROOT_WINDOW (f),
-                           newheight - FRAME_TOP_MARGIN (f), 2);
+      resize_frame_windows (f, newheight, 0);
 
       /* MSDOS frames cannot PRETEND, as they change frame size by
          manipulating video hardware.  */
@@ -5742,9 +5725,7 @@ change_frame_size_1 (register struct frame *f, int newheight, int newwidth, int
 
   if (new_frame_total_cols != FRAME_TOTAL_COLS (f))
     {
-      set_window_width (FRAME_ROOT_WINDOW (f), new_frame_total_cols, 2);
-      if (FRAME_HAS_MINIBUF_P (f))
-        set_window_width (FRAME_MINIBUF_WINDOW (f), new_frame_total_cols, 0);
+      resize_frame_windows (f, new_frame_total_cols, 1);
 
       /* MSDOS frames cannot PRETEND, as they change frame size by
          manipulating video hardware.  */
diff --git a/src/frame.c b/src/frame.c
index 71881265b44..6baf2d0e671 100644
--- a/src/frame.c
+++ b/src/frame.c
@@ -135,11 +135,6 @@ set_menu_bar_lines_1 (Lisp_Object window, int n)
   XSETFASTINT (w->top_line, XFASTINT (w->top_line) + n);
   XSETFASTINT (w->total_lines, XFASTINT (w->total_lines) - n);
 
-  if (INTEGERP (w->orig_top_line))
-    XSETFASTINT (w->orig_top_line, XFASTINT (w->orig_top_line) + n);
-  if (INTEGERP (w->orig_total_lines))
-    XSETFASTINT (w->orig_total_lines, XFASTINT (w->orig_total_lines) - n);
-
   /* Handle just the top child in a vertical split.  */
   if (!NILP (w->vchild))
     set_menu_bar_lines_1 (w->vchild, n);
diff --git a/src/image.c b/src/image.c
index 31b3f01c17d..7d15a4725c5 100644
--- a/src/image.c
+++ b/src/image.c
@@ -7238,7 +7238,7 @@ gif_load (struct frame *f, struct image *img)
               /* From gif89a spec: 1 = "keep in place", 2 = "restore
                  to background".  Treat any other value like 2.  */
               disposal = (extblock->Bytes[0] >> 2) & 7;
-              transparency_color_index = extblock->Bytes[3];
+              transparency_color_index = (unsigned char) extblock->Bytes[3];
               break;
             }
         }
diff --git a/src/w32fns.c b/src/w32fns.c
index bdf9dce9411..823dbe3567e 100644
--- a/src/w32fns.c
+++ b/src/w32fns.c
@@ -1596,7 +1596,7 @@ x_set_tool_bar_lines (struct frame *f, Lisp_Object value, Lisp_Object oldval)
     }
 
   FRAME_TOOL_BAR_LINES (f) = nlines;
-  change_window_heights (root_window, delta);
+  resize_frame_windows (f, FRAME_LINES (f), 0);
   adjust_glyphs (f);
 
   /* We also have to make sure that the internal border at the top of
@@ -1631,6 +1631,9 @@ x_set_tool_bar_lines (struct frame *f, Lisp_Object value, Lisp_Object oldval)
       if (WINDOWP (f->tool_bar_window))
         clear_glyph_matrix (XWINDOW (f->tool_bar_window)->current_matrix);
     }
+
+  run_window_configuration_change_hook (f);
+
 }
 
 
@@ -5822,8 +5825,6 @@ Value is t if tooltip was open, nil otherwise.  */)
   UNGCPRO;
   return unbind_to (count, deleted);
 }
-
-
 
 /***********************************************************************
                         File selection dialog
diff --git a/src/window.c b/src/window.c
index 493972c7545..31a25286bcc 100644
--- a/src/window.c
+++ b/src/window.c
@@ -50,17 +50,15 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include "nsterm.h"
 #endif
 
-Lisp_Object Qwindowp, Qwindow_live_p;
+Lisp_Object Qwindowp, Qwindow_live_p, Qdelete_window;
 static Lisp_Object Qwindow_configuration_p, Qrecord_window_buffer;
-static Lisp_Object Qwindow_deletable_p, Qdelete_window, Qdisplay_buffer;
+static Lisp_Object Qwindow_deletable_p, Qdisplay_buffer;
 static Lisp_Object Qreplace_buffer_in_windows, Qget_mru_window;
 static Lisp_Object Qresize_root_window, Qresize_root_window_vertically;
 static Lisp_Object Qscroll_up, Qscroll_down, Qscroll_command;
 static Lisp_Object Qsafe, Qabove, Qbelow;
 static Lisp_Object Qauto_buffer_name;
 
-static Lisp_Object Qwindow_size_fixed;
-
 static int displayed_window_lines (struct window *);
 static struct window *decode_window (Lisp_Object);
 static int count_windows (struct window *);
@@ -68,13 +66,7 @@ static int get_leaf_windows (struct window *, struct window **, int);
 static void window_scroll (Lisp_Object, int, int, int);
 static void window_scroll_pixel_based (Lisp_Object, int, int, int);
 static void window_scroll_line_based (Lisp_Object, int, int, int);
-static int window_min_size_1 (struct window *, int, int);
-static int window_min_size_2 (struct window *, int, int);
-static int window_min_size (struct window *, int, int, int, int *);
-static void size_window (Lisp_Object, int, int, int, int, int);
 static int freeze_window_start (struct window *, void *);
-static int window_fixed_size_p (struct window *, int, int);
-static void enlarge_window (Lisp_Object, int, int);
 static Lisp_Object window_list (void);
 static int add_window_to_list (struct window *, void *);
 static int candidate_window_p (Lisp_Object, Lisp_Object, Lisp_Object,
@@ -90,6 +82,7 @@ static int foreach_window_1 (struct window *,
                              int (* fn) (struct window *, void *),
                              void *);
 static Lisp_Object window_list_1 (Lisp_Object, Lisp_Object, Lisp_Object);
+static void resize_window_apply (struct window *, int);
 static Lisp_Object select_window (Lisp_Object, Lisp_Object, int);
 
 /* This is the window in which the terminal's cursor should
@@ -1802,9 +1795,7 @@ DEFUN ("set-window-display-table", Fset_window_display_table, Sset_window_displa
   return table;
 }
 
-static void delete_window (Lisp_Object);
-
-/* Record info on buffer window w is displaying
+/* Record info on buffer window W is displaying
    when it is about to cease to display that buffer.  */
 static void
 unshow_buffer (register struct window *w)
@@ -1853,285 +1844,144 @@ unshow_buffer (register struct window *w)
     BVAR (b, last_selected_window) = Qnil;
 }
 
-/* Put replacement into the window structure in place of old. */
+/* Put NEW into the window structure in place of OLD.  SETFLAG zero
+   means change window structure only.  Otherwise store geometry and
+   other settings as well.  */
 static void
-replace_window (Lisp_Object old, Lisp_Object replacement)
+replace_window (Lisp_Object old, Lisp_Object new, int setflag)
 {
   register Lisp_Object tem;
-  register struct window *o = XWINDOW (old), *p = XWINDOW (replacement);
-
-  /* If OLD is its frame's root_window, then replacement is the new
-     root_window for that frame.  */
+  register struct window *o = XWINDOW (old), *n = XWINDOW (new);
 
+  /* If OLD is its frame's root window, then NEW is the new
+     root window for that frame.  */
   if (EQ (old, FRAME_ROOT_WINDOW (XFRAME (o->frame))))
-    FRAME_ROOT_WINDOW (XFRAME (o->frame)) = replacement;
-
-  p->left_col = o->left_col;
-  p->top_line = o->top_line;
-  p->total_cols = o->total_cols;
-  p->total_lines = o->total_lines;
-  p->desired_matrix = p->current_matrix = 0;
-  p->vscroll = 0;
-  memset (&p->cursor, 0, sizeof (p->cursor));
-  memset (&p->last_cursor, 0, sizeof (p->last_cursor));
-  memset (&p->phys_cursor, 0, sizeof (p->phys_cursor));
-  p->phys_cursor_type = -1;
-  p->phys_cursor_width = -1;
-  p->must_be_updated_p = 0;
-  p->pseudo_window_p = 0;
-  XSETFASTINT (p->window_end_vpos, 0);
-  XSETFASTINT (p->window_end_pos, 0);
-  p->window_end_valid = Qnil;
-  p->frozen_window_start_p = 0;
-  p->orig_top_line = p->orig_total_lines = Qnil;
-
-  p->next = tem = o->next;
+    FRAME_ROOT_WINDOW (XFRAME (o->frame)) = new;
+
+  if (setflag)
+    {
+      n->left_col = o->left_col;
+      n->top_line = o->top_line;
+      n->total_cols = o->total_cols;
+      n->total_lines = o->total_lines;
+      n->normal_cols = o->normal_cols;
+      o->normal_cols = make_float (1.0);
+      n->normal_lines = o->normal_lines;
+      o->normal_lines = make_float (1.0);
+      n->desired_matrix = n->current_matrix = 0;
+      n->vscroll = 0;
+      memset (&n->cursor, 0, sizeof (n->cursor));
+      memset (&n->last_cursor, 0, sizeof (n->last_cursor));
+      memset (&n->phys_cursor, 0, sizeof (n->phys_cursor));
+      n->phys_cursor_type = -1;
+      n->phys_cursor_width = -1;
+      n->must_be_updated_p = 0;
+      n->pseudo_window_p = 0;
+      XSETFASTINT (n->window_end_vpos, 0);
+      XSETFASTINT (n->window_end_pos, 0);
+      n->window_end_valid = Qnil;
+      n->frozen_window_start_p = 0;
+    }
+
+  n->next = tem = o->next;
   if (!NILP (tem))
-    XWINDOW (tem)->prev = replacement;
+    XWINDOW (tem)->prev = new;
 
-  p->prev = tem = o->prev;
+  n->prev = tem = o->prev;
   if (!NILP (tem))
-    XWINDOW (tem)->next = replacement;
+    XWINDOW (tem)->next = new;
 
-  p->parent = tem = o->parent;
+  n->parent = tem = o->parent;
   if (!NILP (tem))
     {
       if (EQ (XWINDOW (tem)->vchild, old))
-        XWINDOW (tem)->vchild = replacement;
+        XWINDOW (tem)->vchild = new;
       if (EQ (XWINDOW (tem)->hchild, old))
-        XWINDOW (tem)->hchild = replacement;
+        XWINDOW (tem)->hchild = new;
     }
-
-/*** Here, if replacement is a vertical combination
-and so is its new parent, we should make replacement's
-children be children of that parent instead.  ***/
 }
 
-DEFUN ("delete-window", Fdelete_window, Sdelete_window, 0, 1, "",
-       doc: /* Remove WINDOW from its frame.
-WINDOW defaults to the selected window.  Return nil.
-Signal an error when WINDOW is the only window on its frame.  */)
-  (register Lisp_Object window)
-{
-  struct frame *f;
-  if (NILP (window))
-    window = selected_window;
-  else
-    CHECK_LIVE_WINDOW (window);
-
-  f = XFRAME (WINDOW_FRAME (XWINDOW (window)));
-  delete_window (window);
-
-  run_window_configuration_change_hook (f);
-
-  return Qnil;
-}
+/* If window WINDOW and its parent window are iso-combined, merge
+   WINDOW's children into those of its parent window and mark WINDOW as
+   deleted.  */
 
 static void
-delete_window (register Lisp_Object window)
+recombine_windows (Lisp_Object window)
 {
-  register Lisp_Object tem, parent, sib;
-  register struct window *p;
-  register struct window *par;
-  struct frame *f;
-
-  /* Because this function is called by other C code on non-leaf
-     windows, the CHECK_LIVE_WINDOW macro would choke inappropriately,
-     so we can't decode_window here.  */
-  CHECK_WINDOW (window);
-  p = XWINDOW (window);
-
-  /* It's a no-op to delete an already-deleted window.  */
-  if (NILP (p->buffer)
-      && NILP (p->hchild)
-      && NILP (p->vchild))
-    return;
-
-  parent = p->parent;
-  if (NILP (parent))
-    error ("Attempt to delete minibuffer or sole ordinary window");
-  par = XWINDOW (parent);
-
-  windows_or_buffers_changed++;
-  Vwindow_list = Qnil;
-  f = XFRAME (WINDOW_FRAME (p));
-  FRAME_WINDOW_SIZES_CHANGED (f) = 1;
-
-  /* Are we trying to delete any frame's selected window?  */
-  {
-    Lisp_Object swindow, pwindow;
-
-    /* See if the frame's selected window is either WINDOW
-       or any subwindow of it, by finding all that window's parents
-       and comparing each one with WINDOW.  */
-    swindow = FRAME_SELECTED_WINDOW (f);
-
-    while (1)
-      {
-        pwindow = swindow;
-        while (!NILP (pwindow))
-          {
-            if (EQ (window, pwindow))
-              break;
-            pwindow = XWINDOW (pwindow)->parent;
-          }
-
-        /* If the window being deleted is not a parent of SWINDOW,
-           then SWINDOW is ok as the new selected window.  */
-        if (!EQ (window, pwindow))
-          break;
-        /* Otherwise, try another window for SWINDOW.  */
-        swindow = Fnext_window (swindow, Qlambda, Qnil);
-
-        /* If we get back to the frame's selected window,
-           it means there was no acceptable alternative,
-           so we cannot delete.  */
-        if (EQ (swindow, FRAME_SELECTED_WINDOW (f)))
-          error ("Cannot delete window");
-      }
-
-    /* If we need to change SWINDOW, do it.  */
-    if (! EQ (swindow, FRAME_SELECTED_WINDOW (f)))
-      {
-        /* If we're about to delete the selected window on the
-           selected frame, then we should use Fselect_window to select
-           the new window.  On the other hand, if we're about to
-           delete the selected window on any other frame, we shouldn't do
-           anything but set the frame's selected_window slot.  */
-        if (EQ (FRAME_SELECTED_WINDOW (f), selected_window))
-          Fselect_window (swindow, Qnil);
-        else
-          FRAME_SELECTED_WINDOW (f) = swindow;
-      }
-  }
-
-  /* Now we know we can delete this one.  */
-  window_deletion_count++;
-
-  tem = p->buffer;
-  /* tem is null for dummy parent windows
-     (which have inferiors but not any contents themselves) */
-  if (!NILP (tem))
-    {
-      unshow_buffer (p);
-      unchain_marker (XMARKER (p->pointm));
-      unchain_marker (XMARKER (p->start));
-    }
-
-  /* Free window glyph matrices.  It is sure that they are allocated
-     again when ADJUST_GLYPHS is called.  Block input so that expose
-     events and other events that access glyph matrices are not
-     processed while we are changing them.  */
-  BLOCK_INPUT;
-  free_window_matrices (XWINDOW (FRAME_ROOT_WINDOW (f)));
-
-  tem = p->next;
-  if (!NILP (tem))
-    XWINDOW (tem)->prev = p->prev;
+  struct window *w, *p, *c;
+  Lisp_Object parent, child;
+  int horflag;
 
-  tem = p->prev;
-  if (!NILP (tem))
-    XWINDOW (tem)->next = p->next;
-
-  if (EQ (window, par->hchild))
-    par->hchild = p->next;
-  if (EQ (window, par->vchild))
-    par->vchild = p->next;
-
-  /* Find one of our siblings to give our space to.  */
-  sib = p->prev;
-  if (NILP (sib))
-    {
-      /* If p gives its space to its next sibling, that sibling needs
-         to have its top/left side pulled back to where p's is.
-         set_window_{height,width} will re-position the sibling's
-         children.  */
-      sib = p->next;
-      XWINDOW (sib)->top_line = p->top_line;
-      XWINDOW (sib)->left_col = p->left_col;
-    }
-
-  /* Stretch that sibling.  */
-  if (!NILP (par->vchild))
-    set_window_height (sib,
-                       XFASTINT (XWINDOW (sib)->total_lines) + XFASTINT (p->total_lines),
-                       1);
-  if (!NILP (par->hchild))
-    set_window_width (sib,
-                      XFASTINT (XWINDOW (sib)->total_cols) + XFASTINT (p->total_cols),
-                      1);
-
-  /* If parent now has only one child,
-     put the child into the parent's place.  */
-  tem = par->hchild;
-  if (NILP (tem))
-    tem = par->vchild;
-  if (NILP (XWINDOW (tem)->next)) {
-    replace_window (parent, tem);
-    par = XWINDOW (tem);
-  }
+  w = XWINDOW (window);
+  parent = w->parent;
+  if (!NILP (parent) && NILP (w->nest))
+    {
+      p = XWINDOW (parent);
+      if (((!NILP (p->vchild) && !NILP (w->vchild))
+           || (!NILP (p->hchild) && !NILP (w->hchild))))
+        /* WINDOW and PARENT are both either a vertical or a horizontal
+           combination.  */
+        {
+          horflag = NILP (w->vchild);
+          child = horflag ? w->hchild : w->vchild;
+          c = XWINDOW (child);
 
-  /* Since we may be deleting combination windows, we must make sure that
-     not only p but all its children have been marked as deleted.  */
-  if (! NILP (p->hchild))
-    delete_all_subwindows (p->hchild);
-  else if (! NILP (p->vchild))
-    delete_all_subwindows (p->vchild);
+          /* Splice WINDOW's children into its parent's children and
+             assign new normal sizes.  */
+          if (NILP (w->prev))
+            if (horflag)
+              p->hchild = child;
+            else
+              p->vchild = child;
+          else
+            {
+              c->prev = w->prev;
+              XWINDOW (w->prev)->next = child;
+            }
 
-  /* Mark this window as deleted.  */
-  p->buffer = p->hchild = p->vchild = Qnil;
+          while (c)
+            {
+              c->parent = parent;
 
-  if (! NILP (par->parent))
-    par = XWINDOW (par->parent);
+              if (horflag)
+                c->normal_cols
+                  = make_float (XFLOATINT (c->total_cols)
+                                / XFLOATINT (p->total_cols));
+              else
+                c->normal_lines
+                  = make_float (XFLOATINT (c->total_lines)
+                                / XFLOATINT (p->total_lines));
 
-  /* Check if we have a v/hchild with a v/hchild.  In that case remove
-     one of them.  */
+              if (NILP (c->next))
+                {
+                  if (!NILP (w->next))
+                    {
+                      c->next = w->next;
+                      XWINDOW (c->next)->prev = child;
+                    }
 
-  if (! NILP (par->vchild) && ! NILP (XWINDOW (par->vchild)->vchild))
-    {
-      p = XWINDOW (par->vchild);
-      par->vchild = p->vchild;
-      tem = p->vchild;
-    }
-  else if (! NILP (par->hchild) && ! NILP (XWINDOW (par->hchild)->hchild))
-    {
-      p = XWINDOW (par->hchild);
-      par->hchild = p->hchild;
-      tem = p->hchild;
-    }
-  else
-    p = 0;
+                  c = 0;
+                }
+              else
+                {
+                  child = c->next;
+                  c = XWINDOW (child);
+                }
+            }
 
-  if (p)
-    {
-      while (! NILP (tem)) {
-        XWINDOW (tem)->parent = p->parent;
-        if (NILP (XWINDOW (tem)->next))
-          break;
-        tem = XWINDOW (tem)->next;
-      }
-      if (! NILP (tem)) {
-        /* The next of the v/hchild we are removing is now the next of the
-           last child for the v/hchild:
-           Before v/hchild -> v/hchild -> next1 -> next2
-                    |
-                     -> next3
-           After:  v/hchild -> next1 -> next2 -> next3
-        */
-        XWINDOW (tem)->next = p->next;
-        if (! NILP (p->next))
-          XWINDOW (p->next)->prev = tem;
-      }
-      p->next = p->prev = p->vchild = p->hchild = p->buffer = Qnil;
+          /* WINDOW can be deleted now.  */
+          w->vchild = w->hchild = Qnil;
+        }
     }
-
-
-  /* Adjust glyph matrices. */
-  adjust_glyphs (f);
-  UNBLOCK_INPUT;
 }
 
-
+/* If WINDOW can be deleted, delete it.  */
+Lisp_Object
+delete_deletable_window (Lisp_Object window)
+{
+  if (!NILP (call1 (Qwindow_deletable_p, window)))
+    call1 (Qdelete_window, window);
+}
 
 /***********************************************************************
                              Window List
@@ -2427,43 +2277,6 @@ reverse order.  */)
 }
 
 
-DEFUN ("window-list-1", Fwindow_list_1, Swindow_list_1, 0, 3, 0,
-       doc: /* Return a list of all live windows.
-WINDOW specifies the first window to list and defaults to the selected
-window.
-
-Optional argument MINIBUF nil or omitted means consider the minibuffer
-window only if the minibuffer is active.  MINIBUF t means consider the
-minibuffer window even if the minibuffer is not active.  Any other value
-means do not consider the minibuffer window even if the minibuffer is
-active.
-
-Optional argument ALL-FRAMES nil or omitted means consider all windows
-on WINDOW's frame, plus the minibuffer window if specified by the
-MINIBUF argument.  If the minibuffer counts, consider all windows on all
-frames that share that minibuffer too.  The following non-nil values of
-ALL-FRAMES have special meanings:
-
-- t means consider all windows on all existing frames.
-
-- `visible' means consider all windows on all visible frames.
-
-- 0 (the number zero) means consider all windows on all visible and
-  iconified frames.
-
-- A frame means consider all windows on that frame only.
-
-Anything else means consider all windows on WINDOW's frame and no
-others.
-
-If WINDOW is not on the list of windows returned, some other window will
-be listed first but no error is signalled.  */)
-  (Lisp_Object window, Lisp_Object minibuf, Lisp_Object all_frames)
-{
-  return window_list_1 (window, minibuf, all_frames);
-}
-
-
 DEFUN ("other-window", Fother_window, Sother_window, 1, 2, "p",
        doc: /* Select another window in cyclic ordering of windows.
 COUNT specifies the number of windows to skip, starting with the
@@ -2547,6 +2360,41 @@ MINIBUF neither nil nor t means never include the minibuffer window.  */)
 }
 
 
+DEFUN ("window-list-1", Fwindow_list_1, Swindow_list_1, 0, 3, 0,
+       doc: /* Return a list of all live windows.
+WINDOW specifies the first window to list and defaults to the selected
+window.
+
+Optional argument MINIBUF nil or omitted means consider the minibuffer
+window only if the minibuffer is active.  MINIBUF t means consider the
+minibuffer window even if the minibuffer is not active.  Any other value
+means do not consider the minibuffer window even if the minibuffer is
+active.
+
+Optional argument ALL-FRAMES nil or omitted means consider all windows
+on WINDOW's frame, plus the minibuffer window if specified by the
+MINIBUF argument.  If the minibuffer counts, consider all windows on all
+frames that share that minibuffer too.  The following non-nil values of
+ALL-FRAMES have special meanings:
+
+- t means consider all windows on all existing frames.
+
+- `visible' means consider all windows on all visible frames.
+
+- 0 (the number zero) means consider all windows on all visible and
+  iconified frames.
+
+- A frame means consider all windows on that frame only.
+
+Anything else means consider all windows on WINDOW's frame and no
+others.
+
+If WINDOW is not on the list of windows returned, some other window will
+be listed first but no error is signalled.  */)
+  (Lisp_Object window, Lisp_Object minibuf, Lisp_Object all_frames)
+{
+  return window_list_1 (window, minibuf, all_frames);
+}
 
 /* Look at all windows, performing an operation specified by TYPE
    with argument OBJ.
@@ -2560,7 +2408,6 @@ enum window_loop
 {
   WINDOW_LOOP_UNUSED,
   GET_BUFFER_WINDOW,            /* Arg is buffer */
-  DELETE_OTHER_WINDOWS,         /* Arg is window not to delete */
   DELETE_BUFFER_WINDOWS,        /* Arg is buffer */
   UNSHOW_BUFFER,                /* Arg is buffer */
   REDISPLAY_BUFFER_WINDOWS,     /* Arg is buffer */
@@ -2644,11 +2491,6 @@ window_loop (enum window_loop type, Lisp_Object obj, int mini, Lisp_Object frame
               }
             break;
 
-          case DELETE_OTHER_WINDOWS:
-            if (!EQ (window, obj))
-              Fdelete_window (window);
-            break;
-
           case DELETE_BUFFER_WINDOWS:
             if (EQ (w->buffer, obj))
               {
@@ -2684,7 +2526,7 @@ window_loop (enum window_loop type, Lisp_Object obj, int mini, Lisp_Object frame
                       Fset_buffer (w->buffer);
                   }
                 else
-                  Fdelete_window (window);
+                  call1 (Qdelete_window, window);
               }
             break;
 
@@ -2719,7 +2561,7 @@ window_loop (enum window_loop type, Lisp_Object obj, int mini, Lisp_Object frame
                     XSETWINDOW (window_to_delete, w);
                     /* If this window is dedicated and not the only window
                        in its frame, then kill it.  */
-                    Fdelete_window (window_to_delete);
+                        call1 (Qdelete_window, window_to_delete);
                   }
                 else
                   {
@@ -2801,68 +2643,248 @@ selected frame and no others.  */)
     return Qnil;
 }
 
-DEFUN ("delete-other-windows", Fdelete_other_windows, Sdelete_other_windows,
-       0, 1, "",
-       doc: /* Make WINDOW (or the selected window) fill its frame.
-Only the frame WINDOW is on is affected.
-This function tries to reduce display jumps by keeping the text
+Lisp_Object
+resize_root_window (Lisp_Object window, Lisp_Object delta, Lisp_Object horizontal, Lisp_Object ignore)
+{
+  return call4 (Qresize_root_window, window, delta, horizontal, ignore);
+}
+
+
+DEFUN ("delete-other-windows-internal", Fdelete_other_windows_internal,
+       Sdelete_other_windows_internal, 0, 2, "",
+       doc: /* Make WINDOW fill its frame.
+Only the frame WINDOW is on is affected.  WINDOW may be any window and
+defaults to the selected one.
+
+Optional argument ROOT, if non-nil, must specify an internal window
+containing WINDOW as a subwindow.  If this is the case, replace ROOT by
+WINDOW and leave alone any windows not contained in ROOT.
+
+When WINDOW is live try to reduce display jumps by keeping the text
 previously visible in WINDOW in the same place on the frame.  Doing this
 depends on the value of (window-start WINDOW), so if calling this
 function in a program gives strange scrolling, make sure the
 window-start value is reasonable when this function is called.  */)
-  (Lisp_Object window)
+     (Lisp_Object window, Lisp_Object root)
 {
-  struct window *w;
+  struct window *w, *r, *s;
+  struct frame *f;
+  Lisp_Object sibling, pwindow, swindow, delta;
   EMACS_INT startpos;
-  int top, new_top;
+  int top, new_top, resize_failed;
 
-  if (NILP (window))
-    window = selected_window;
-  else
-    CHECK_LIVE_WINDOW (window);
-  w = XWINDOW (window);
+  w = decode_any_window (window);
+  XSETWINDOW (window, w);
+  f = XFRAME (w->frame);
 
-  startpos = marker_position (w->start);
-  top = WINDOW_TOP_EDGE_LINE (w) - FRAME_TOP_MARGIN (XFRAME (WINDOW_FRAME (w)));
+  if (NILP (root))
+    /* ROOT is the frame's root window.  */
+    {
+      root = FRAME_ROOT_WINDOW (f);
+      r = XWINDOW (root);
+    }
+  else
+    /* ROOT must be an ancestor of WINDOW.  */
+    {
+      r = decode_any_window (root);
+      pwindow = XWINDOW (window)->parent;
+      while (!NILP (pwindow))
+        if (EQ (pwindow, root))
+          break;
+        else
+          pwindow = XWINDOW (pwindow)->parent;
+      if (!EQ (pwindow, root))
+        error ("Specified root is not an ancestor of specified window");
+    }
 
-  if (MINI_WINDOW_P (w) && top > 0)
+  if (EQ (window, root))
+    /* A noop.  */
+    return Qnil;
+  /* I don't understand the "top > 0" part below.  If we deal with a
+     standalone minibuffer it would have been caught by the preceding
+     test.  */
+  else if (MINI_WINDOW_P (w)) /* && top > 0) */
     error ("Can't expand minibuffer to full frame");
 
-  window_loop (DELETE_OTHER_WINDOWS, window, 0, WINDOW_FRAME (w));
+  if (!NILP (w->buffer))
+    {
+      startpos = marker_position (w->start);
+      top = WINDOW_TOP_EDGE_LINE (w)
+        - FRAME_TOP_MARGIN (XFRAME (WINDOW_FRAME (w)));
+      /* Make sure WINDOW is the frame's selected window.  */
+      if (!EQ (window, FRAME_SELECTED_WINDOW (f)))
+        {
+          if (EQ (selected_frame, w->frame))
+            Fselect_window (window, Qnil);
+          else
+            FRAME_SELECTED_WINDOW (f) = window;
+        }
+    }
+  else
+    {
+      /* See if the frame's selected window is a subwindow of WINDOW, by
+         finding all the selected window's parents and comparing each
+         one with WINDOW.  If it isn't we need a new selected window for
+         this frame.  */
+      swindow = FRAME_SELECTED_WINDOW (f);
+      while (1)
+        {
+          pwindow = swindow;
+          while (!NILP (pwindow) && !EQ (window, pwindow))
+            pwindow = XWINDOW (pwindow)->parent;
+
+          if (EQ (window, pwindow))
+            /* If WINDOW is an ancestor of SWINDOW, then SWINDOW is ok
+               as the new selected window.  */
+            break;
+          else
+            /* Else try the previous window of SWINDOW.  */
+            swindow = Fprevious_window (swindow, Qlambda, Qnil);
+        }
 
-  /* Try to minimize scrolling, by setting the window start to the point
-     will cause the text at the old window start to be at the same place
-     on the frame.  But don't try to do this if the window start is
-     outside the visible portion (as might happen when the display is
-     not current, due to typeahead).  */
-  new_top = WINDOW_TOP_EDGE_LINE (w) - FRAME_TOP_MARGIN (XFRAME (WINDOW_FRAME (w)));
-  if (new_top != top
-      && startpos >= BUF_BEGV (XBUFFER (w->buffer))
-      && startpos <= BUF_ZV (XBUFFER (w->buffer)))
+      if (!EQ (swindow, FRAME_SELECTED_WINDOW (f)))
+        {
+          if (EQ (selected_frame, w->frame))
+            Fselect_window (swindow, Qnil);
+          else
+            FRAME_SELECTED_WINDOW (f) = swindow;
+        }
+    }
+
+  BLOCK_INPUT;
+  free_window_matrices (r);
+
+  windows_or_buffers_changed++;
+  Vwindow_list = Qnil;
+  FRAME_WINDOW_SIZES_CHANGED (f) = 1;
+
+  if (NILP (w->buffer))
     {
-      struct position pos;
-      struct buffer *obuf = current_buffer;
+      resize_failed = 0;
+      /* Resize subwindows vertically.  */
+      XSETINT (delta, XINT (r->total_lines) - XINT (w->total_lines));
+      w->top_line = r->top_line;
+      resize_root_window (window, delta, Qnil, Qnil);
+      if (resize_window_check (w, 0))
+        resize_window_apply (w, 0);
+      else
+        {
+          resize_root_window (window, delta, Qnil, Qt);
+          if (resize_window_check (w, 0))
+            resize_window_apply (w, 0);
+          else
+            resize_failed = 1;
+        }
 
-      Fset_buffer (w->buffer);
-      /* This computation used to temporarily move point, but that can
-         have unwanted side effects due to text properties.  */
-      pos = *vmotion (startpos, -top, w);
+      /* Resize subwindows horizontally.  */
+      if (!resize_failed)
+        {
+          w->left_col = r->left_col;
+          XSETINT (delta, XINT (r->total_cols) - XINT (w->total_cols));
+          w->left_col = r->left_col;
+          resize_root_window (window, delta, Qt, Qnil);
+          if (resize_window_check (w, 1))
+            resize_window_apply (w, 1);
+          else
+            {
+              resize_root_window (window, delta, Qt, Qt);
+              if (resize_window_check (w, 1))
+                resize_window_apply (w, 1);
+              else
+                resize_failed = 1;
+            }
+        }
 
-      set_marker_both (w->start, w->buffer, pos.bufpos, pos.bytepos);
-      w->window_end_valid = Qnil;
-      w->start_at_line_beg = ((pos.bytepos == BEGV_BYTE
-                               || FETCH_BYTE (pos.bytepos - 1) == '\n') ? Qt
-                              : Qnil);
-      /* We need to do this, so that the window-scroll-functions
-         get called.  */
-      w->optional_new_start = Qt;
+      if (resize_failed)
+        /* Play safe, if we still can ...  */
+        {
+          window = swindow;
+          w = XWINDOW (window);
+        }
+    }
 
-      set_buffer_internal (obuf);
+  /* Cleanly unlink WINDOW from window-tree.  */
+  if (!NILP (w->prev))
+    /* Get SIBLING above (on the left of) WINDOW.  */
+    {
+      sibling = w->prev;
+      s = XWINDOW (sibling);
+      s->next = w->next;
+      if (!NILP (s->next))
+        XWINDOW (s->next)->prev = sibling;
+    }
+  else
+    /* Get SIBLING below (on the right of) WINDOW.  */
+    {
+      sibling = w->next;
+      s = XWINDOW (sibling);
+      s->prev = Qnil;
+      if (!NILP (XWINDOW (w->parent)->vchild))
+        XWINDOW (w->parent)->vchild = sibling;
+      else
+        XWINDOW (w->parent)->hchild = sibling;
+    }
+
+  /* Delete ROOT and all subwindows of ROOT.  */
+  if (!NILP (r->vchild))
+    {
+      delete_all_subwindows (r->vchild);
+      r->vchild = Qnil;
+    }
+  else if (!NILP (r->hchild))
+    {
+      delete_all_subwindows (r->hchild);
+      r->hchild = Qnil;
     }
 
+  replace_window (root, window, 1);
+
+  /* Reset WINDOW's splits status.  */
+  w->splits = Qnil;
+
+  /* This must become SWINDOW anyway ....... */
+  if (!NILP (w->buffer) && !resize_failed)
+    {
+      /* Try to minimize scrolling, by setting the window start to the
+         point will cause the text at the old window start to be at the
+         same place on the frame.  But don't try to do this if the
+         window start is outside the visible portion (as might happen
+         when the display is not current, due to typeahead).  */
+      new_top = WINDOW_TOP_EDGE_LINE (w) - FRAME_TOP_MARGIN (XFRAME (WINDOW_FRAME (w)));
+      if (new_top != top
+          && startpos >= BUF_BEGV (XBUFFER (w->buffer))
+          && startpos <= BUF_ZV (XBUFFER (w->buffer)))
+        {
+          struct position pos;
+          struct buffer *obuf = current_buffer;
+
+          Fset_buffer (w->buffer);
+          /* This computation used to temporarily move point, but that
+             can have unwanted side effects due to text properties.  */
+          pos = *vmotion (startpos, -top, w);
+
+          set_marker_both (w->start, w->buffer, pos.bufpos, pos.bytepos);
+          w->window_end_valid = Qnil;
+          w->start_at_line_beg = ((pos.bytepos == BEGV_BYTE
+                                   || FETCH_BYTE (pos.bytepos - 1) == '\n') ? Qt
+                                  : Qnil);
+          /* We need to do this, so that the window-scroll-functions
+             get called.  */
+          w->optional_new_start = Qt;
+
+          set_buffer_internal (obuf);
+        }
+    }
+
+  adjust_glyphs (f);
+  UNBLOCK_INPUT;
+
+  run_window_configuration_change_hook (f);
+
   return Qnil;
 }
 
+
 DEFUN ("delete-windows-on", Fdelete_windows_on, Sdelete_windows_on,
        0, 2, "bDelete windows on (buffer): ",
        doc: /* Delete all windows showing BUFFER-OR-NAME.
@@ -2944,8 +2966,6 @@ replace_buffer_in_all_windows (Lisp_Object buffer)
     window_loop (UNSHOW_BUFFER, buffer, 1, frame);
 }
 
-/* Set the height of WINDOW and all its inferiors.  */
-
 /* If *ROWS or *COLS are too small a size for FRAME, set them to the
    minimum allowable size.  */
 
@@ -2969,243 +2989,6 @@ check_frame_size (FRAME_PTR frame, int *rows, int *cols)
     *cols = MIN_SAFE_WINDOW_WIDTH;
 }
 
-/* Value is non-zero if window W is fixed-size.  WIDTH_P non-zero means
-   check if W's width can be changed, otherwise check W's height.
-   CHECK_SIBLINGS_P non-zero means check resizablity of WINDOW's
-   siblings, too.  If none of the siblings is resizable, WINDOW isn't
-   either.  */
-
-static int
-window_fixed_size_p (struct window *w, int width_p, int check_siblings_p)
-{
-  int fixed_p;
-  struct window *c;
-
-  if (!NILP (w->hchild))
-    {
-      c = XWINDOW (w->hchild);
-
-      if (width_p)
-        {
-          /* A horizontal combination is fixed-width if all of if its
-             children are.  */
-          while (c && window_fixed_size_p (c, width_p, 0))
-            c = WINDOWP (c->next) ? XWINDOW (c->next) : NULL;
-          fixed_p = c == NULL;
-        }
-      else
-        {
-          /* A horizontal combination is fixed-height if one of if its
-             children is.  */
-          while (c && !window_fixed_size_p (c, width_p, 0))
-            c = WINDOWP (c->next) ? XWINDOW (c->next) : NULL;
-          fixed_p = c != NULL;
-        }
-    }
-  else if (!NILP (w->vchild))
-    {
-      c = XWINDOW (w->vchild);
-
-      if (width_p)
-        {
-          /* A vertical combination is fixed-width if one of if its
-             children is.  */
-          while (c && !window_fixed_size_p (c, width_p, 0))
-            c = WINDOWP (c->next) ? XWINDOW (c->next) : NULL;
-          fixed_p = c != NULL;
-        }
-      else
-        {
-          /* A vertical combination is fixed-height if all of if its
-             children are.  */
-          while (c && window_fixed_size_p (c, width_p, 0))
-            c = WINDOWP (c->next) ? XWINDOW (c->next) : NULL;
-          fixed_p = c == NULL;
-        }
-    }
-  else if (BUFFERP (w->buffer))
-    {
-      struct buffer *old = current_buffer;
-      Lisp_Object val;
-
-      current_buffer = XBUFFER (w->buffer);
-      val = find_symbol_value (Qwindow_size_fixed);
-      current_buffer = old;
-
-      fixed_p = 0;
-      if (!EQ (val, Qunbound))
-        {
-          fixed_p = !NILP (val);
-
-          if (fixed_p
-              && ((EQ (val, Qheight) && width_p)
-                  || (EQ (val, Qwidth) && !width_p)))
-            fixed_p = 0;
-        }
-
-      /* Can't tell if this one is resizable without looking at
-         siblings.  If all siblings are fixed-size this one is too.  */
-      if (!fixed_p && check_siblings_p && WINDOWP (w->parent))
-        {
-          Lisp_Object child;
-
-          for (child = w->prev; WINDOWP (child); child = XWINDOW (child)->prev)
-            if (!window_fixed_size_p (XWINDOW (child), width_p, 0))
-              break;
-
-          if (NILP (child))
-            for (child = w->next; WINDOWP (child); child = XWINDOW (child)->next)
-              if (!window_fixed_size_p (XWINDOW (child), width_p, 0))
-                break;
-
-          if (NILP (child))
-            fixed_p = 1;
-        }
-    }
-  else
-    fixed_p = 1;
-
-  return fixed_p;
-}
-
-/* Return minimum size of leaf window W.  WIDTH_P non-zero means return
-   the minimum width of W, WIDTH_P zero means return the minimum height
-   of W.  SAFE_P non-zero means ignore window-min-height|width but just
-   return values that won't crash Emacs and don't hide components like
-   fringes, scrollbars, or modelines.  If WIDTH_P is zero and W is the
-   minibuffer window, always return 1.  */
-
-static int
-window_min_size_2 (struct window *w, int width_p, int safe_p)
-{
-  /* We should consider buffer-local values of window_min_height and
-     window_min_width here.  */
-  if (width_p)
-    {
-      int safe_size = (MIN_SAFE_WINDOW_WIDTH
-                       + WINDOW_FRINGE_COLS (w)
-                       + WINDOW_SCROLL_BAR_COLS (w));
-
-      return safe_p ? safe_size : max (window_min_width, safe_size);
-    }
-  else if (MINI_WINDOW_P (w))
-    return 1;
-  else
-    {
-      int safe_size = (MIN_SAFE_WINDOW_HEIGHT
-                       + ((BUFFERP (w->buffer)
-                           && !NILP (BVAR (XBUFFER (w->buffer), mode_line_format)))
-                          ? 1 : 0));
-
-      return safe_p ? safe_size : max (window_min_height, safe_size);
-    }
-}
-
-/* Return minimum size of window W, not taking fixed-width windows into
-   account.  WIDTH_P non-zero means return the minimum width, otherwise
-   return the minimum height.  SAFE_P non-zero means ignore
-   window-min-height|width but just return values that won't crash Emacs
-   and don't hide components like fringes, scrollbars, or modelines.  If
-   W is a combination window, compute the minimum size from the minimum
-   sizes of W's children.  */
-
-static int
-window_min_size_1 (struct window *w, int width_p, int safe_p)
-{
-  struct window *c;
-  int size;
-
-  if (!NILP (w->hchild))
-    {
-      /* W is a horizontal combination.  */
-      c = XWINDOW (w->hchild);
-      size = 0;
-
-      if (width_p)
-        {
-          /* The minimum width of a horizontal combination is the sum of
-             the minimum widths of its children.  */
-          while (c)
-            {
-              size += window_min_size_1 (c, 1, safe_p);
-              c = WINDOWP (c->next) ? XWINDOW (c->next) : NULL;
-            }
-        }
-      else
-        {
-          /* The minimum height of a horizontal combination is the
-             maximum of the minimum heights of its children.  */
-          while (c)
-            {
-              size = max (window_min_size_1 (c, 0, safe_p), size);
-              c = WINDOWP (c->next) ? XWINDOW (c->next) : NULL;
-            }
-        }
-    }
-  else if (!NILP (w->vchild))
-    {
-      /* W is a vertical combination.  */
-      c = XWINDOW (w->vchild);
-      size = 0;
-
-      if (width_p)
-        {
-          /* The minimum width of a vertical combination is the maximum
-             of the minimum widths of its children.  */
-          while (c)
-            {
-              size = max (window_min_size_1 (c, 1, safe_p), size);
-              c = WINDOWP (c->next) ? XWINDOW (c->next) : NULL;
-            }
-        }
-      else
-        {
-          /* The minimum height of a vertical combination is the sum of
-             the minimum height of its children.  */
-          while (c)
-            {
-              size += window_min_size_1 (c, 0, safe_p);
-              c = WINDOWP (c->next) ? XWINDOW (c->next) : NULL;
-            }
-        }
-    }
-  else
-    /* W is a leaf window.  */
-    size = window_min_size_2 (w, width_p, safe_p);
-
-  return size;
-}
-
-/* Return the minimum size of window W, taking fixed-size windows into
-   account.  WIDTH_P non-zero means return the minimum width, otherwise
-   return the minimum height.  SAFE_P non-zero means ignore
-   window-min-height|width but just return values that won't crash Emacs
-   and don't hide components like fringes, scrollbars, or modelines.
-   IGNORE_FIXED_P non-zero means ignore if W is fixed-size.  Set *FIXED
-   to 1 if W is fixed-size unless FIXED is null.  */
-
-static int
-window_min_size (struct window *w, int width_p, int safe_p, int ignore_fixed_p, int *fixed)
-{
-  int size, fixed_p;
-
-  if (ignore_fixed_p)
-    fixed_p = 0;
-  else
-    fixed_p = window_fixed_size_p (w, width_p, 1);
-
-  if (fixed)
-    *fixed = fixed_p;
-
-  if (fixed_p)
-    size = WINDOW_TOTAL_SIZE (w, width_p);
-  else
-    size = window_min_size_1 (w, width_p, safe_p);
-
-  return size;
-}
-
-
 /* Adjust the margins of window W if text area is too small.
    Return 1 if window width is ok after adjustment; 0 if window
    is still too narrow.  */
@@ -3240,410 +3023,6 @@ adjust_window_margins (struct window *w)
     w->left_margin_cols = make_number (margin_cols);
   return 1;
 }
-
-/* Calculate new sizes for windows in the list FORWARD when their
-   compound size goes from TOTAL to SIZE.  TOTAL must be greater than
-   SIZE.  The number of windows in FORWARD is NCHILDREN, and the number
-   that can shrink is SHRINKABLE.  Fixed-size windows may be shrunk if
-   and only if RESIZE_FIXED_P is non-zero.  WIDTH_P non-zero means
-   shrink columns, otherwise shrink lines.
-
-   SAFE_P zero means windows may be sized down to window-min-height
-   lines (window-min-window columns for WIDTH_P non-zero).  SAFE_P
-   non-zero means windows may be sized down to their minimum safe sizes
-   taking into account the space needed to display modelines, fringes,
-   and scrollbars.
-
-   This function returns an allocated array of new sizes that the caller
-   must free.  A size -1 means the window is fixed and RESIZE_FIXED_P is
-   zero.  A size zero means the window shall be deleted.  Array index 0
-   refers to the first window in FORWARD, 1 to the second, and so on.
-
-   This function resizes windows proportionally to their size.  It also
-   tries to preserve smaller windows by resizing larger windows before
-   resizing any window to zero.  If resize_proportionally is non-nil for
-   a specific window, it will attempt to strictly resize that window
-   proportionally, even at the expense of deleting smaller windows.  */
-static int *
-shrink_windows (int total, int size, int nchildren, int shrinkable,
-                int resize_fixed_p, Lisp_Object forward, int width_p, int safe_p)
-{
-  int available_resize = 0;
-  int *new_sizes, *min_sizes;
-  struct window *c;
-  Lisp_Object child;
-  int smallest = total;
-  int total_removed = 0;
-  int total_shrink = total - size;
-  int i;
-
-  new_sizes = xmalloc (sizeof (*new_sizes) * nchildren);
-  min_sizes = xmalloc (sizeof (*min_sizes) * nchildren);
-
-  for (i = 0, child = forward; !NILP (child); child = c->next, ++i)
-    {
-      int child_size;
-
-      c = XWINDOW (child);
-      child_size = WINDOW_TOTAL_SIZE (c, width_p);
-
-      if (!resize_fixed_p && window_fixed_size_p (c, width_p, 0))
-        new_sizes[i] = -1;
-      else
-        {
-          new_sizes[i] = child_size;
-          min_sizes[i] = window_min_size_1 (c, width_p, safe_p);
-          if (child_size > min_sizes[i]
-              && NILP (c->resize_proportionally))
-            available_resize += child_size - min_sizes[i];
-        }
-    }
-  /* We might need to shrink some windows to zero.  Find the smallest
-     windows and set them to 0 until we can fulfil the new size.  */
-
-  while (shrinkable > 1 && size + available_resize < total)
-    {
-      for (i = 0; i < nchildren; ++i)
-        if (new_sizes[i] > 0 && smallest > new_sizes[i])
-          smallest = new_sizes[i];
-
-      for (i = 0; i < nchildren; ++i)
-        if (new_sizes[i] == smallest)
-          {
-            /* Resize this window down to zero.  */
-            new_sizes[i] = 0;
-            if (smallest > min_sizes[i])
-              available_resize -= smallest - min_sizes[i];
-            available_resize += smallest;
-            --shrinkable;
-            total_removed += smallest;
-
-            /* We don't know what the smallest is now.  */
-            smallest = total;
-
-            /* Out of for, just remove one window at the time and
-               check again if we have enough space.  */
-            break;
-          }
-    }
-
-  /* Now, calculate the new sizes.  Try to shrink each window
-     proportional to its size.  */
-  for (i = 0; i < nchildren; ++i)
-    {
-      if (new_sizes[i] > min_sizes[i])
-        {
-          int to_shrink = total_shrink * new_sizes[i] / total;
-
-          if (new_sizes[i] - to_shrink < min_sizes[i])
-            to_shrink = new_sizes[i] - min_sizes[i];
-          new_sizes[i] -= to_shrink;
-          total_removed += to_shrink;
-        }
-    }
-
-  /* Any reminder due to rounding, we just subtract from windows
-     that are left and still can be shrunk.  */
-  while (total_shrink > total_removed)
-    {
-      int nonzero_sizes = 0;
-
-      for (i = 0; i < nchildren; ++i)
-        if (new_sizes[i] > 0)
-          ++nonzero_sizes;
-
-      for (i = 0; i < nchildren; ++i)
-        if (new_sizes[i] > min_sizes[i])
-          {
-            --new_sizes[i];
-            ++total_removed;
-
-            /* Out of for, just shrink one window at the time and
-               check again if we have enough space.  */
-            break;
-          }
-
-      /* Special case, only one window left.  */
-      if (nonzero_sizes == 1)
-        break;
-    }
-
-  /* Any surplus due to rounding, we add to windows that are left.  */
-  while (total_shrink < total_removed)
-    {
-      for (i = 0; i < nchildren; ++i)
-        {
-          if (new_sizes[i] != 0 && total_shrink < total_removed)
-            {
-              ++new_sizes[i];
-              --total_removed;
-              break;
-            }
-        }
-    }
-
-  xfree (min_sizes);
-
-  return new_sizes;
-}
-
-/* Set WINDOW's height or width to SIZE.  WIDTH_P non-zero means set
-   WINDOW's width.  Resize WINDOW's children, if any, so that they keep
-   their proportionate size relative to WINDOW.
-
-   If FIRST_ONLY is 1, change only the first of WINDOW's children when
-   they are in series.  If LAST_ONLY is 1, change only the last of
-   WINDOW's children when they are in series.
-
-   Propagate WINDOW's top or left edge position to children.  Delete
-   windows that become too small unless NODELETE_P is 1.  When
-   NODELETE_P equals 2 do not honor settings for window-min-height and
-   window-min-width when resizing windows but use safe defaults instead.
-   This should give better behavior when resizing frames.  */
-
-static void
-size_window (Lisp_Object window, int size, int width_p, int nodelete_p, int first_only, int last_only)
-{
-  struct window *w = XWINDOW (window);
-  struct window *c;
-  Lisp_Object child, *forward, *sideward;
-  int old_size = WINDOW_TOTAL_SIZE (w, width_p);
-
-  size = max (0, size);
-
-  /* Delete WINDOW if it's too small.  */
-  if (nodelete_p != 1 && !NILP (w->parent)
-      && size < window_min_size_1 (w, width_p, nodelete_p == 2))
-    {
-      delete_window (window);
-      return;
-    }
-
-  /* Set redisplay hints.  */
-  w->last_modified = make_number (0);
-  w->last_overlay_modified = make_number (0);
-  windows_or_buffers_changed++;
-  FRAME_WINDOW_SIZES_CHANGED (XFRAME (w->frame)) = 1;
-
-  if (width_p)
-    {
-      sideward = &w->vchild;
-      forward = &w->hchild;
-      w->total_cols = make_number (size);
-      adjust_window_margins (w);
-    }
-  else
-    {
-      sideward = &w->hchild;
-      forward = &w->vchild;
-      w->total_lines = make_number (size);
-      w->orig_total_lines = Qnil;
-    }
-
-  if (!NILP (*sideward))
-    {
-      /* We have a chain of parallel siblings whose size should all change.  */
-      for (child = *sideward; !NILP (child); child = c->next)
-        {
-          c = XWINDOW (child);
-          if (width_p)
-            c->left_col = w->left_col;
-          else
-            c->top_line = w->top_line;
-          size_window (child, size, width_p, nodelete_p,
-                       first_only, last_only);
-        }
-    }
-  else if (!NILP (*forward) && last_only)
-    {
-      /* Change the last in a series of siblings.  */
-      Lisp_Object last_child;
-      int child_size;
-
-      child = *forward;
-      do
-        {
-          c = XWINDOW (child);
-          last_child = child;
-          child = c->next;
-        }
-      while (!NILP (child));
-
-      child_size = WINDOW_TOTAL_SIZE (c, width_p);
-      size_window (last_child, size - old_size + child_size,
-                   width_p, nodelete_p, first_only, last_only);
-    }
-  else if (!NILP (*forward) && first_only)
-    {
-      /* Change the first in a series of siblings.  */
-      int child_size;
-
-      child = *forward;
-      c = XWINDOW (child);
-
-      if (width_p)
-        c->left_col = w->left_col;
-      else
-        c->top_line = w->top_line;
-
-      child_size = WINDOW_TOTAL_SIZE (c, width_p);
-      size_window (child, size - old_size + child_size,
-                   width_p, nodelete_p, first_only, last_only);
-    }
-  else if (!NILP (*forward))
-    {
-      int fixed_size, each IF_LINT (= 0), extra IF_LINT (= 0), n;
-      int resize_fixed_p, nfixed;
-      int last_pos, first_pos, nchildren, total;
-      int *new_sizes = NULL;
-
-      /* Determine the fixed-size portion of this window, and the
-         number of child windows.  */
-      fixed_size = nchildren = nfixed = total = 0;
-      for (child = *forward; !NILP (child); child = c->next, ++nchildren)
-        {
-          int child_size;
-
-          c = XWINDOW (child);
-          child_size = WINDOW_TOTAL_SIZE (c, width_p);
-          total += child_size;
-
-          if (window_fixed_size_p (c, width_p, 0))
-            {
-              fixed_size += child_size;
-              ++nfixed;
-            }
-        }
-
-      /* If the new size is smaller than fixed_size, or if there
-         aren't any resizable windows, allow resizing fixed-size
-         windows.  */
-      resize_fixed_p = nfixed == nchildren || size < fixed_size;
-
-      /* Compute how many lines/columns to add/remove to each child.  The
-         value of extra takes care of rounding errors.  */
-      n = resize_fixed_p ? nchildren : nchildren - nfixed;
-      if (size < total && n > 1)
-        new_sizes = shrink_windows (total, size, nchildren, n,
-                                    resize_fixed_p, *forward, width_p,
-                                    nodelete_p == 2);
-      else
-        {
-          each = (size - total) / n;
-          extra = (size - total) - n * each;
-        }
-
-      /* Compute new children heights and edge positions.  */
-      first_pos = width_p ? XINT (w->left_col) : XINT (w->top_line);
-      last_pos = first_pos;
-      for (n = 0, child = *forward; !NILP (child); child = c->next, ++n)
-        {
-          int new_child_size, old_child_size;
-
-          c = XWINDOW (child);
-          old_child_size = WINDOW_TOTAL_SIZE (c, width_p);
-          new_child_size = old_child_size;
-
-          /* The top or left edge position of this child equals the
-             bottom or right edge of its predecessor.  */
-          if (width_p)
-            c->left_col = make_number (last_pos);
-          else
-            c->top_line = make_number (last_pos);
-
-          /* If this child can be resized, do it.  */
-          if (resize_fixed_p || !window_fixed_size_p (c, width_p, 0))
-            {
-              new_child_size =
-                new_sizes ? new_sizes[n] : old_child_size + each + extra;
-              extra = 0;
-            }
-
-          /* Set new size.  Note that size_window also propagates
-             edge positions to children, so it's not a no-op if we
-             didn't change the child's size.  */
-          size_window (child, new_child_size, width_p, 1,
-                       first_only, last_only);
-
-          /* Remember the bottom/right edge position of this child; it
-             will be used to set the top/left edge of the next child.  */
-          last_pos += new_child_size;
-        }
-
-      xfree (new_sizes);
-
-      /* We should have covered the parent exactly with child windows.  */
-      xassert (size == last_pos - first_pos);
-
-      /* Now delete any children that became too small.  */
-      if (nodelete_p != 1)
-        for (child = *forward; !NILP (child); child = c->next)
-          {
-            int child_size;
-
-            c = XWINDOW (child);
-            child_size = WINDOW_TOTAL_SIZE (c, width_p);
-            size_window (child, child_size, width_p, nodelete_p,
-                         first_only, last_only);
-          }
-    }
-}
-
-/* Set WINDOW's height to HEIGHT, and recursively change the height of
-   WINDOW's children.  NODELETE zero means windows that have become
-   smaller than window-min-height in the process may be deleted.
-   NODELETE 1 means never delete windows that become too small in the
-   process.  (The caller should check later and do so if appropriate.)
-   NODELETE 2 means delete only windows that have become too small to be
-   displayed correctly.  */
-
-void
-set_window_height (Lisp_Object window, int height, int nodelete)
-{
-  size_window (window, height, 0, nodelete, 0, 0);
-}
-
-/* Set WINDOW's width to WIDTH, and recursively change the width of
-   WINDOW's children.  NODELETE zero means windows that have become
-   smaller than window-min-width in the process may be deleted.
-   NODELETE 1 means never delete windows that become too small in the
-   process.  (The caller should check later and do so if appropriate.)
-   NODELETE 2 means delete only windows that have become too small to be
-   displayed correctly.  */
-
-void
-set_window_width (Lisp_Object window, int width, int nodelete)
-{
-  size_window (window, width, 1, nodelete, 0, 0);
-}
-
-/* Change window heights in windows rooted in WINDOW by N lines.  */
-
-void
-change_window_heights (Lisp_Object window, int n)
-{
-  struct window *w = XWINDOW (window);
-
-  XSETFASTINT (w->top_line, XFASTINT (w->top_line) + n);
-  XSETFASTINT (w->total_lines, XFASTINT (w->total_lines) - n);
-
-  if (INTEGERP (w->orig_top_line))
-    XSETFASTINT (w->orig_top_line, XFASTINT (w->orig_top_line) + n);
-  if (INTEGERP (w->orig_total_lines))
-    XSETFASTINT (w->orig_total_lines, XFASTINT (w->orig_total_lines) - n);
-
-  /* Handle just the top child in a vertical split.  */
-  if (!NILP (w->vchild))
-    change_window_heights (w->vchild, n);
-
-  /* Adjust all children in a horizontal split.  */
-  for (window = w->hchild; !NILP (window); window = w->next)
-    {
-      w = XWINDOW (window);
-      change_window_heights (window, n);
-    }
-}
-
 
 int window_select_count;
 
@@ -3676,12 +3055,6 @@ run_window_configuration_change_hook (struct frame *f)
   if (NILP (Vrun_hooks))
     return;
 
-  if (SELECTED_FRAME () != f)
-    {
-      record_unwind_protect (select_frame_norecord, Fselected_frame ());
-      Fselect_frame (frame, Qt);
-    }
-
   /* Use the right buffer.  Matters when running the local hooks.  */
   if (current_buffer != XBUFFER (Fwindow_buffer (Qnil)))
     {
@@ -3689,6 +3062,12 @@ run_window_configuration_change_hook (struct frame *f)
       Fset_buffer (Fwindow_buffer (Qnil));
     }
 
+  if (SELECTED_FRAME () != f)
+    {
+      record_unwind_protect (select_frame_norecord, Fselected_frame ());
+      select_frame_norecord (frame);
+    }
+
   /* Look for buffer-local values.  */
   {
     Lisp_Object windows = Fwindow_list (frame, Qlambda, Qnil);
@@ -3699,12 +3078,12 @@ run_window_configuration_change_hook (struct frame *f)
         if (!NILP (Flocal_variable_p (Qwindow_configuration_change_hook,
                                       buffer)))
           {
-            int count1 = SPECPDL_INDEX ();
+            int count = SPECPDL_INDEX ();
             record_unwind_protect (select_window_norecord, Fselected_window ());
             select_window_norecord (window);
             run_funs (Fbuffer_local_value (Qwindow_configuration_change_hook,
                                            buffer));
-            unbind_to (count1, Qnil);
+            unbind_to (count, Qnil);
           }
       }
   }
@@ -3713,6 +3092,16 @@ run_window_configuration_change_hook (struct frame *f)
   unbind_to (count, Qnil);
 }
 
+DEFUN ("run-window-configuration-change-hook", Frun_window_configuration_change_hook,
+       Srun_window_configuration_change_hook, 1, 1, 0,
+       doc: /* Run `window-configuration-change-hook' for FRAME.  */)
+     (Lisp_Object frame)
+{
+  CHECK_LIVE_FRAME (frame);
+  run_window_configuration_change_hook (XFRAME (frame));
+  return Qnil;
+}
+
 /* Make WINDOW display BUFFER as its contents.  RUN_HOOKS_P non-zero
    means it's allowed to run hooks.  See make_frame for a case where
    it's not allowed.  KEEP_MARGINS_P non-zero means that the current
@@ -4000,10 +3389,13 @@ DEFUN ("internal-temp-output-buffer-show",
   return Qnil;
 }
 
+/* Make new window, have it replace WINDOW in window-tree, and make
+   WINDOW its only vertical child (HORFLAG 1 means make WINDOW its only
+   horizontal child).   */
 static void
-make_dummy_parent (Lisp_Object window)
+make_parent_window (Lisp_Object window, int horflag)
 {
-  Lisp_Object new;
+  Lisp_Object parent;
   register struct window *o, *p;
   int i;
 
@@ -4011,30 +3403,27 @@ make_dummy_parent (Lisp_Object window)
   p = allocate_window ();
   for (i = 0; i < VECSIZE (struct window); ++i)
     ((struct Lisp_Vector *) p)->contents[i]
-      = ((struct Lisp_Vector *)o)->contents[i];
-  XSETWINDOW (new, p);
+      = ((struct Lisp_Vector *) o)->contents[i];
+  XSETWINDOW (parent, p);
 
   ++sequence_number;
   XSETFASTINT (p->sequence_number, sequence_number);
   XSETFASTINT (p->clone_number, sequence_number);
 
-  /* Put new into window structure in place of window */
-  replace_window (window, new);
+  replace_window (window, parent, 1);
 
   o->next = Qnil;
   o->prev = Qnil;
-  o->vchild = Qnil;
-  o->hchild = Qnil;
-  o->parent = new;
+  o->parent = parent;
 
+  p->hchild = horflag ? window : Qnil;
+  p->vchild = horflag ? Qnil : window;
   p->start = Qnil;
   p->pointm = Qnil;
   p->buffer = Qnil;
-
   p->splits = Qnil;
   p->nest = Qnil;
   p->window_parameters = Qnil;
-
 }
 
 /* Make new window from scratch.  */
@@ -4096,7 +3485,6 @@ make_window (void)
   w->pseudo_window_p = 0;
   w->frozen_window_start_p = 0;
   w->vscroll = 0;
-  w->resize_proportionally = Qnil;
   /* Reset window_list.  */
   Vwindow_list = Qnil;
   /* Return window.  */
@@ -4138,872 +3526,770 @@ Note: This function does not operate on any subwindows of WINDOW.  */)
   return w->new_normal;
 }
 
-DEFUN ("split-window", Fsplit_window, Ssplit_window, 0, 3, "",
-       doc: /* Split WINDOW, putting SIZE lines in the first of the pair.
-WINDOW defaults to selected one and SIZE to half its size.
-If optional third arg HORIZONTAL is non-nil, split side by side and put
-SIZE columns in the first of the pair.  In that case, SIZE includes that
-window's scroll bar, or the divider column to its right.
-Interactively, all arguments are nil.
-Returns the newly created window (which is the lower or rightmost one).
-The upper or leftmost window is the original one, and remains selected
-if it was selected before.
+/* Return 1 if setting w->total_lines (w->total_cols if HORFLAG is
+   non-zero) to w->new_total would result in correct heights (widths)
+   for window W and recursively all subwindows of W.
 
-See Info node `(elisp)Splitting Windows' for more details and examples.  */)
-  (Lisp_Object window, Lisp_Object size, Lisp_Object horizontal)
+   Note: This function does not check any of `window-fixed-size-p',
+   `window-min-height' or `window-min-width'.  It does check that window
+   sizes do not drop below one line (two columns). */
+int
+resize_window_check (struct window *w, int horflag)
 {
-  register Lisp_Object new;
-  register struct window *o, *p;
-  FRAME_PTR fo;
-  register int size_int;
-
-  if (NILP (window))
-    window = selected_window;
-  else
-    CHECK_LIVE_WINDOW (window);
-
-  o = XWINDOW (window);
-  fo = XFRAME (WINDOW_FRAME (o));
+  struct window *c;
 
-  if (NILP (size))
+  if (!NILP (w->vchild))
+    /* W is a vertical combination.  */
     {
-      if (!NILP (horizontal))
-        /* Calculate the size of the left-hand window, by dividing
-           the usable space in columns by two.
-           We round up, since the left-hand window may include
-           a dividing line, while the right-hand may not.  */
-        size_int = (XFASTINT (o->total_cols) + 1) >> 1;
+      c = XWINDOW (w->vchild);
+      if (horflag)
+        /* All subwindows of W must have the same width as W.  */
+        {
+          while (c)
+            {
+              if ((XINT (c->new_total) != XINT (w->new_total))
+                  || !resize_window_check (c, horflag))
+                return 0;
+              c = NILP (c->next) ? 0 : XWINDOW (c->next);
+            }
+          return 1;
+        }
       else
-        size_int = XFASTINT (o->total_lines) >> 1;
+        /* The sum of the heights of the subwindows of W must equal W's
+           height.  */
+        {
+          int sum_of_sizes = 0;
+          while (c)
+            {
+              if (!resize_window_check (c, horflag))
+                return 0;
+              sum_of_sizes = sum_of_sizes + XINT (c->new_total);
+              c = NILP (c->next) ? 0 : XWINDOW (c->next);
+            }
+          return (sum_of_sizes == XINT (w->new_total));
+        }
     }
-  else
+  else if (!NILP (w->hchild))
+    /* W is a horizontal combination.  */
     {
-      CHECK_NUMBER (size);
-      size_int = XINT (size);
+      c = XWINDOW (w->hchild);
+      if (horflag)
+        /* The sum of the widths of the subwindows of W must equal W's
+           width.  */
+        {
+          int sum_of_sizes = 0;
+          while (c)
+            {
+              if (!resize_window_check (c, horflag))
+                return 0;
+              sum_of_sizes = sum_of_sizes + XINT (c->new_total);
+              c = NILP (c->next) ? 0 : XWINDOW (c->next);
+            }
+          return (sum_of_sizes == XINT (w->new_total));
+        }
+      else
+        /* All subwindows of W must have the same height as W.  */
+        {
+          while (c)
+            {
+              if ((XINT (c->new_total) != XINT (w->new_total))
+                  || !resize_window_check (c, horflag))
+                return 0;
+              c = NILP (c->next) ? 0 : XWINDOW (c->next);
+            }
+          return 1;
+        }
     }
+  else
+    /* A leaf window.  Make sure it's not too small.  The following
+       hardcodes the values of `window-safe-min-width' (2) and
+       `window-safe-min-height' (1) which are defined in window.el.  */
+    return XINT (w->new_total) >= (horflag ? 2 : 1);
+}
 
-  if (MINI_WINDOW_P (o))
-    error ("Attempt to split minibuffer window");
-  else if (window_fixed_size_p (o, !NILP (horizontal), 0))
-    error ("Attempt to split fixed-size window");
+/* Set w->total_lines (w->total_cols if HORIZONTAL is non-zero) to
+   w->new_total for window W and recursively all subwindows of W.  Also
+   calculate and assign the new vertical (horizontal) start positions of
+   each of these windows.
 
-  if (NILP (horizontal))
+   This function does not perform any error checks.  Make sure you have
+   run resize_window_check on W before applying this function.  */
+static void
+resize_window_apply (struct window *w, int horflag)
+{
+  struct window *c, *p;
+  int pos;
+
+  /* Note: Assigning new_normal requires that the new total size of the
+     parent window has been set *before*.  */
+  if (horflag)
     {
-      int window_safe_height = window_min_size_2 (o, 0, 0);
+      w->total_cols = w->new_total;
+      if (NUMBERP (w->new_normal))
+        w->normal_cols = w->new_normal;
 
-      if (size_int < window_safe_height)
-        error ("Window height %d too small (after splitting)", size_int);
-      if (size_int + window_safe_height > XFASTINT (o->total_lines))
-        error ("Window height %d too small (after splitting)",
-               (int) (XFASTINT (o->total_lines) - size_int));
-      if (NILP (o->parent)
-          || NILP (XWINDOW (o->parent)->vchild))
-        {
-          make_dummy_parent (window);
-          new = o->parent;
-          XWINDOW (new)->vchild = window;
-        }
+      pos = XINT (w->left_col);
     }
   else
     {
-      int window_safe_width = window_min_size_2 (o, 1, 0);
+      w->total_lines = w->new_total;
+      if (NUMBERP (w->new_normal))
+        w->normal_lines = w->new_normal;
 
-      if (size_int < window_safe_width)
-        error ("Window width %d too small (after splitting)", size_int);
-      if (size_int + window_safe_width > XFASTINT (o->total_cols))
-        error ("Window width %d too small (after splitting)",
-               (int) (XFASTINT (o->total_cols) - size_int));
-      if (NILP (o->parent)
-          || NILP (XWINDOW (o->parent)->hchild))
-        {
-          make_dummy_parent (window);
-          new = o->parent;
-          XWINDOW (new)->hchild = window;
-        }
+      pos = XINT (w->top_line);
     }
 
-  /* Now we know that window's parent is a vertical combination
-     if we are dividing vertically, or a horizontal combination
-     if we are making side-by-side windows */
-
-  windows_or_buffers_changed++;
-  FRAME_WINDOW_SIZES_CHANGED (fo) = 1;
-  new = make_window ();
-  p = XWINDOW (new);
-
-  p->frame = o->frame;
-  p->next = o->next;
-  if (!NILP (p->next))
-    XWINDOW (p->next)->prev = new;
-  p->prev = window;
-  o->next = new;
-  p->parent = o->parent;
-  p->buffer = Qt;
-  p->window_end_valid = Qnil;
-  memset (&p->last_cursor, 0, sizeof p->last_cursor);
-
-  /* Duplicate special geometry settings.  */
-
-  p->left_margin_cols = o->left_margin_cols;
-  p->right_margin_cols = o->right_margin_cols;
-  p->left_fringe_width = o->left_fringe_width;
-  p->right_fringe_width = o->right_fringe_width;
-  p->fringes_outside_margins = o->fringes_outside_margins;
-  p->scroll_bar_width = o->scroll_bar_width;
-  p->vertical_scroll_bar_type = o->vertical_scroll_bar_type;
-
-  /* Apportion the available frame space among the two new windows */
-
-  if (!NILP (horizontal))
-    {
-      p->total_lines = o->total_lines;
-      p->top_line = o->top_line;
-      XSETFASTINT (p->total_cols, XFASTINT (o->total_cols) - size_int);
-      XSETFASTINT (o->total_cols, size_int);
-      XSETFASTINT (p->left_col, XFASTINT (o->left_col) + size_int);
-      adjust_window_margins (p);
-      adjust_window_margins (o);
+  if (!NILP (w->vchild))
+    /* W is a vertical combination.  */
+    {
+      c = XWINDOW (w->vchild);
+      while (c)
+        {
+          if (horflag)
+            XSETFASTINT (c->left_col, pos);
+          else
+            XSETFASTINT (c->top_line, pos);
+          resize_window_apply (c, horflag);
+          if (!horflag)
+            pos = pos + XINT (c->total_lines);
+          c = NILP (c->next) ? 0 : XWINDOW (c->next);
+        }
     }
-  else
+  else if (!NILP (w->hchild))
+    /* W is a horizontal combination.  */
     {
-      p->left_col = o->left_col;
-      p->total_cols = o->total_cols;
-      XSETFASTINT (p->total_lines, XFASTINT (o->total_lines) - size_int);
-      XSETFASTINT (o->total_lines, size_int);
-      XSETFASTINT (p->top_line, XFASTINT (o->top_line) + size_int);
+      c = XWINDOW (w->hchild);
+      while (c)
+        {
+          if (horflag)
+            XSETFASTINT (c->left_col, pos);
+          else
+            XSETFASTINT (c->top_line, pos);
+          resize_window_apply (c, horflag);
+          if (horflag)
+            pos = pos + XINT (c->total_cols);
+          c = NILP (c->next) ? 0 : XWINDOW (c->next);
+        }
     }
 
-  /* Adjust glyph matrices.  */
-  adjust_glyphs (fo);
-
-  Fset_window_buffer (new, o->buffer, Qt);
-  return new;
-}
-
-DEFUN ("enlarge-window", Fenlarge_window, Senlarge_window, 1, 2, "p",
-       doc: /* Make selected window SIZE lines taller.
-Interactively, if no argument is given, make the selected window one
-line taller.  If optional argument HORIZONTAL is non-nil, make selected
-window wider by SIZE columns.  If SIZE is negative, shrink the window by
--SIZE lines or columns.  Return nil.
-
-This function can delete windows if they get too small.  The size of
-fixed size windows is not altered by this function.  */)
-  (Lisp_Object size, Lisp_Object horizontal)
-{
-  CHECK_NUMBER (size);
-  enlarge_window (selected_window, XINT (size), !NILP (horizontal));
-
-  run_window_configuration_change_hook (SELECTED_FRAME ());
-
-  return Qnil;
+  /* Clear out some redisplay caches.  */
+  XSETFASTINT (w->last_modified, 0);
+  XSETFASTINT (w->last_overlay_modified, 0);
 }
 
-DEFUN ("shrink-window", Fshrink_window, Sshrink_window, 1, 2, "p",
-       doc: /* Make selected window SIZE lines smaller.
-Interactively, if no argument is given, make the selected window one
-line smaller.  If optional argument HORIZONTAL is non-nil, make the
-window narrower by SIZE columns.  If SIZE is negative, enlarge selected
-window by -SIZE lines or columns.  Return nil.
-
-This function can delete windows if they get too small.  The size of
-fixed size windows is not altered by this function. */)
-  (Lisp_Object size, Lisp_Object horizontal)
-{
-  CHECK_NUMBER (size);
-  enlarge_window (selected_window, -XINT (size), !NILP (horizontal));
-
-  run_window_configuration_change_hook (SELECTED_FRAME ());
 
-  return Qnil;
-}
+DEFUN ("resize-window-apply", Fresize_window_apply, Sresize_window_apply, 1, 2, 0,
+       doc: /* Apply requested size values for window-tree of FRAME.
+Optional argument HORIZONTAL omitted or nil means apply requested height
+values.  HORIZONTAL non-nil means apply requested width values.
 
-static int
-window_height (Lisp_Object window)
-{
-  register struct window *p = XWINDOW (window);
-  return WINDOW_TOTAL_LINES (p);
-}
+This function checks whether the requested values sum up to a valid
+window layout, recursively assigns the new sizes of all subwindows and
+calculates and assigns the new start positions of these windows.
 
-static int
-window_width (Lisp_Object window)
+Note: This function does not check any of `window-fixed-size-p',
+`window-min-height' or `window-min-width'.  All these checks have to
+be applied on the Elisp level.  */)
+     (Lisp_Object frame, Lisp_Object horizontal)
 {
-  register struct window *p = XWINDOW (window);
-  return WINDOW_TOTAL_COLS (p);
-}
-
-
-#define CURBEG(w) \
-  *(horiz_flag ? &(XWINDOW (w)->left_col) : &(XWINDOW (w)->top_line))
-
-#define CURSIZE(w) \
-  *(horiz_flag ? &(XWINDOW (w)->total_cols) : &(XWINDOW (w)->total_lines))
-
+  struct frame *f;
+  struct window *r;
+  int horflag = !NILP (horizontal);
 
-/* Enlarge WINDOW by DELTA.  HORIZ_FLAG nonzero means enlarge it
-   horizontally; zero means do it vertically.
+  if (NILP (frame))
+    frame = selected_frame;
+  CHECK_LIVE_FRAME (frame);
 
-   Siblings of the selected window are resized to fulfill the size
-   request.  If they become too small in the process, they may be
-   deleted.  */
+  f = XFRAME (frame);
+  r = XWINDOW (FRAME_ROOT_WINDOW (f));
 
-static void
-enlarge_window (Lisp_Object window, int delta, int horiz_flag)
-{
-  Lisp_Object parent, next, prev;
-  struct window *p;
-  Lisp_Object *sizep;
-  int maximum;
-  int (*sizefun) (Lisp_Object)
-    = horiz_flag ? window_width : window_height;
-  void (*setsizefun) (Lisp_Object, int, int)
-    = (horiz_flag ? set_window_width : set_window_height);
+  if (!resize_window_check (r, horflag)
+      || ! EQ (r->new_total, (horflag ? r->total_cols : r->total_lines)))
+    return Qnil;
 
-  /* Give up if this window cannot be resized.  */
-  if (window_fixed_size_p (XWINDOW (window), horiz_flag, 1))
-    error ("Window is not resizable");
+  BLOCK_INPUT;
+  resize_window_apply (r, horflag);
 
-  /* Find the parent of the selected window.  */
-  while (1)
-    {
-      p = XWINDOW (window);
-      parent = p->parent;
+  windows_or_buffers_changed++;
+  FRAME_WINDOW_SIZES_CHANGED (f) = 1;
 
-      if (NILP (parent))
-        {
-          if (horiz_flag)
-            error ("No other window to side of this one");
-          break;
-        }
+  adjust_glyphs (f);
+  UNBLOCK_INPUT;
 
-      if (horiz_flag
-          ? !NILP (XWINDOW (parent)->hchild)
-          : !NILP (XWINDOW (parent)->vchild))
-        break;
+  run_window_configuration_change_hook (f);
 
-      window = parent;
-    }
+  return Qt;
+}
 
-  sizep = &CURSIZE (window);
 
-  {
-    register int maxdelta;
-
-    /* Compute the maximum size increment this window can have.  */
-
-    maxdelta = (!NILP (parent) ? (*sizefun) (parent) - XINT (*sizep)
-                /* This is a main window followed by a minibuffer.  */
-                : !NILP (p->next) ? ((*sizefun) (p->next)
-                                     - window_min_size (XWINDOW (p->next),
-                                                        horiz_flag, 0, 0, 0))
-                /* This is a minibuffer following a main window.  */
-                : !NILP (p->prev) ? ((*sizefun) (p->prev)
-                                     - window_min_size (XWINDOW (p->prev),
-                                                        horiz_flag, 0, 0, 0))
-                /* This is a frame with only one window, a minibuffer-only
-                   or a minibufferless frame.  */
-                : (delta = 0));
-
-    if (delta > maxdelta)
-      /* This case traps trying to make the minibuffer
-         the full frame, or make the only window aside from the
-         minibuffer the full frame.  */
-      delta = maxdelta;
-  }
+/* Resize frame F's windows when number of lines of F is set to SIZE.
+   HORFLAG 1 means resize windows when number of columns of F is set to
+   SIZE.
 
-  if (XINT (*sizep) + delta < window_min_size (XWINDOW (window),
-                                               horiz_flag, 0, 0, 0))
+   This function can delete all windows but the selected one in order to
+   satisfy the request.  The result will be meaningful if and only if
+   F's windows have meaningful sizes when you call this.  */
+void
+resize_frame_windows (struct frame *f, int size, int horflag)
+{
+  Lisp_Object root = f->root_window;
+  struct window *r = XWINDOW (root);
+  Lisp_Object mini = f->minibuffer_window;
+  struct window *m;
+  /* new_size is the new size of the frame's root window.  */
+  int new_size = (horflag
+                  ? size
+                  : (size
+                     - FRAME_TOP_MARGIN (f)
+                     - ((FRAME_HAS_MINIBUF_P (f) && !FRAME_MINIBUF_ONLY_P (f))
+                        ? 1 : 0)));
+
+  XSETFASTINT (r->top_line, FRAME_TOP_MARGIN (f));
+  if (NILP (r->vchild) && NILP (r->hchild))
+    /* For a leaf root window just set the size.  */
+    if (horflag)
+      XSETFASTINT (r->total_cols, new_size);
+    else
+      XSETFASTINT (r->total_lines, new_size);
+  else
     {
-      delete_window (window);
-      return;
-    }
-
-  if (delta == 0)
-    return;
+      /* old_size is the old size of the frame's root window.  */
+      int old_size = XFASTINT (horflag ? r->total_cols : r->total_lines);
+      Lisp_Object delta;
 
-  /* Find the total we can get from other siblings without deleting them.  */
-  maximum = 0;
-  for (next = p->next; WINDOWP (next); next = XWINDOW (next)->next)
-    maximum += (*sizefun) (next) - window_min_size (XWINDOW (next),
-                                                    horiz_flag, 0, 0, 0);
-  for (prev = p->prev; WINDOWP (prev); prev = XWINDOW (prev)->prev)
-    maximum += (*sizefun) (prev) - window_min_size (XWINDOW (prev),
-                                                    horiz_flag, 0, 0, 0);
-
-  /* If we can get it all from them without deleting them, do so.  */
-  if (delta <= maximum)
-    {
-      Lisp_Object first_unaffected;
-      Lisp_Object first_affected;
-      int fixed_p;
-
-      next = p->next;
-      prev = p->prev;
-      first_affected = window;
-      /* Look at one sibling at a time,
-         moving away from this window in both directions alternately,
-         and take as much as we can get without deleting that sibling.  */
-      while (delta != 0
-             && (!NILP (next) || !NILP (prev)))
+      XSETINT (delta, new_size - old_size);
+      /* Try a "normal" resize first.  */
+      resize_root_window (root, delta, horflag ? Qt : Qnil, Qnil);
+      if (resize_window_check (r, horflag) && new_size == XINT (r->new_total))
+        resize_window_apply (r, horflag);
+      else
         {
-          if (! NILP (next))
-            {
-              int this_one = ((*sizefun) (next)
-                              - window_min_size (XWINDOW (next), horiz_flag,
-                                                 0, 0, &fixed_p));
-              if (!fixed_p)
-                {
-                  if (this_one > delta)
-                    this_one = delta;
-
-                  (*setsizefun) (next, (*sizefun) (next) - this_one, 0);
-                  (*setsizefun) (window, XINT (*sizep) + this_one, 0);
-
-                  delta -= this_one;
-                }
-
-              next = XWINDOW (next)->next;
-            }
-
-          if (delta == 0)
-            break;
-
-          if (! NILP (prev))
+          /* Try with "reasonable" minimum sizes next.  */
+          resize_root_window (root, delta, horflag ? Qt : Qnil, Qt);
+          if (resize_window_check (r, horflag)
+              && new_size == XINT (r->new_total))
+            resize_window_apply (r, horflag);
+          else
             {
-              int this_one = ((*sizefun) (prev)
-                              - window_min_size (XWINDOW (prev), horiz_flag,
-                                                 0, 0, &fixed_p));
-              if (!fixed_p)
+              /* Finally, try with "safe" minimum sizes.  */
+              resize_root_window (root, delta, horflag ? Qt : Qnil, Qsafe);
+              if (resize_window_check (r, horflag)
+                  && new_size == XINT (r->new_total))
+                resize_window_apply (r, horflag);
+              else
                 {
-                  if (this_one > delta)
-                    this_one = delta;
-
-                  first_affected = prev;
-
-                  (*setsizefun) (prev, (*sizefun) (prev) - this_one, 0);
-                  (*setsizefun) (window, XINT (*sizep) + this_one, 0);
-
-                  delta -= this_one;
+                  /* We lost.  Delete all windows but the frame's
+                     selected one.  */
+                  root = f->selected_window;
+                  Fdelete_other_windows_internal (root, Qnil);
+                  if (horflag)
+                    XSETFASTINT (XWINDOW (root)->total_cols, new_size);
+                  else
+                    XSETFASTINT (XWINDOW (root)->total_lines, new_size);
                 }
-
-              prev = XWINDOW (prev)->prev;
             }
         }
-
-      xassert (delta == 0);
-
-      /* Now recalculate the edge positions of all the windows affected,
-         based on the new sizes.  */
-      first_unaffected = next;
-      prev = first_affected;
-      for (next = XWINDOW (prev)->next; ! EQ (next, first_unaffected);
-           prev = next, next = XWINDOW (next)->next)
-        {
-          XSETINT (CURBEG (next), XINT (CURBEG (prev)) + (*sizefun) (prev));
-          /* This does not change size of NEXT,
-             but it propagates the new top edge to its children */
-          (*setsizefun) (next, (*sizefun) (next), 0);
-        }
     }
-  else
-    {
-      register int delta1;
-      register int opht = (*sizefun) (parent);
-
-      if (opht <= XINT (*sizep) + delta)
-        {
-          /* If trying to grow this window to or beyond size of the parent,
-             just delete all the sibling windows.  */
-          Lisp_Object start, tem;
-
-          start = XWINDOW (parent)->vchild;
-          if (NILP (start))
-            start = XWINDOW (parent)->hchild;
 
-          /* Delete any siblings that come after WINDOW.  */
-          tem = XWINDOW (window)->next;
-          while (! NILP (tem))
-            {
-              Lisp_Object next1 = XWINDOW (tem)->next;
-              delete_window (tem);
-              tem = next1;
-            }
-
-          /* Delete any siblings that come after WINDOW.
-             Note that if START is not WINDOW, then WINDOW still
-             has siblings, so WINDOW has not yet replaced its parent.  */
-          tem = start;
-          while (! EQ (tem, window))
-            {
-              Lisp_Object next1 = XWINDOW (tem)->next;
-              delete_window (tem);
-              tem = next1;
-            }
-        }
+  if (FRAME_HAS_MINIBUF_P (f) && !FRAME_MINIBUF_ONLY_P (f))
+    {
+      m = XWINDOW (mini);
+      if (horflag)
+        XSETFASTINT (m->total_cols, size);
       else
         {
-          /* Otherwise, make delta1 just right so that if we add
-             delta1 lines to this window and to the parent, and then
-             shrink the parent back to its original size, the new
-             proportional size of this window will increase by delta.
-
-             The function size_window will compute the new height h'
-             of the window from delta1 as:
-
-             e = delta1/n
-             x = delta1 - delta1/n * n for the 1st resizable child
-             h' = h + e + x
-
-             where n is the number of children that can be resized.
-             We can ignore x by choosing a delta1 that is a multiple of
-             n.  We want the height of this window to come out as
-
-             h' = h + delta
-
-             So, delta1 must be
-
-             h + e = h + delta
-             delta1/n = delta
-             delta1 = n * delta.
-
-             The number of children n equals the number of resizable
-             children of this window + 1 because we know window itself
-             is resizable (otherwise we would have signaled an error).
-
-             This reasoning is not correct when other windows become too
-             small and shrink_windows refuses to delete them.  Below we
-             use resize_proportionally to work around this problem.  */
-
-          struct window *w = XWINDOW (window);
-          Lisp_Object s;
-          int n = 1;
-
-          for (s = w->next; WINDOWP (s); s = XWINDOW (s)->next)
-            if (!window_fixed_size_p (XWINDOW (s), horiz_flag, 0))
-              ++n;
-          for (s = w->prev; WINDOWP (s); s = XWINDOW (s)->prev)
-            if (!window_fixed_size_p (XWINDOW (s), horiz_flag, 0))
-              ++n;
-
-          delta1 = n * delta;
-
-          /* Add delta1 lines or columns to this window, and to the parent,
-             keeping things consistent while not affecting siblings.  */
-          XSETINT (CURSIZE (parent), opht + delta1);
-          (*setsizefun) (window, XINT (*sizep) + delta1, 0);
-
-          /* Squeeze out delta1 lines or columns from our parent,
-             shrinking this window and siblings proportionately.  This
-             brings parent back to correct size.  Delta1 was calculated
-             so this makes this window the desired size, taking it all
-             out of the siblings.
-
-             Temporarily set resize_proportionally to Qt to assure that,
-             if necessary, shrink_windows deletes smaller windows rather
-             than shrink this window.  */
-          w->resize_proportionally = Qt;
-          (*setsizefun) (parent, opht, 0);
-          w->resize_proportionally = Qnil;
+          /* Are we sure we always want 1 line here?  */
+          XSETFASTINT (m->total_lines, 1);
+          XSETFASTINT (m->top_line, XINT (r->top_line) + XINT (r->total_lines));
         }
     }
+}
 
-  XSETFASTINT (p->last_modified, 0);
-  XSETFASTINT (p->last_overlay_modified, 0);
 
-  /* Adjust glyph matrices. */
-  adjust_glyphs (XFRAME (WINDOW_FRAME (XWINDOW (window))));
-}
+DEFUN ("split-window-internal", Fsplit_window_internal, Ssplit_window_internal, 4, 4, 0,
+       doc: /* Split window OLD.
+Second argument TOTAL-SIZE specifies the number of lines or columns of the
+new window.  In any case TOTAL-SIZE must be a positive integer 
 
+Third argument SIDE nil (or `below') specifies that the new window shall
+be located below WINDOW.  SIDE `above' means the new window shall be
+located above WINDOW.  In both cases TOTAL-SIZE specifies the number of
+lines of the new window including space reserved for the mode and/or
+header line.
 
-/* Adjust the size of WINDOW by DELTA, moving only its trailing edge.
-   HORIZ_FLAG nonzero means adjust the width, moving the right edge.
-   zero means adjust the height, moving the bottom edge.
+SIDE t (or `right') specifies that the new window shall be located on
+the right side of WINDOW.  SIDE `left' means the new window shall be
+located on the left of WINDOW.  In both cases TOTAL-SIZE specifies the
+number of columns of the new window including space reserved for fringes
+and the scrollbar or a divider column.
 
-   Following siblings of the selected window are resized to fulfill
-   the size request.  If they become too small in the process, they
-   are not deleted; instead, we signal an error.  */
+Fourth argument NORMAL-SIZE specifies the normal size of the new window
+according to the SIDE argument.
 
-static void
-adjust_window_trailing_edge (Lisp_Object window, int delta, int horiz_flag)
+The new total and normal sizes of all involved windows must have been
+set correctly.  See the code of `split-window' for how this is done.  */)
+  (Lisp_Object old, Lisp_Object total_size, Lisp_Object side, Lisp_Object normal_size)
 {
-  Lisp_Object parent, child;
-  struct window *p;
-  Lisp_Object old_config = Fcurrent_window_configuration (Qnil);
-  int delcount = window_deletion_count;
-
-  CHECK_WINDOW (window);
+  /* OLD (*o) is the window we have to split.  (*p) is either OLD's
+     parent window or an internal window we have to install as OLD's new
+     parent.  REFERENCE (*r) must denote a live window, or is set to OLD
+     provided OLD is a leaf window, or to the frame's selected window.
+     NEW (*n) is the new window created with some parameters taken from
+     REFERENCE (*r).  */
+  register Lisp_Object new, frame, reference;
+  register struct window *o, *p, *n, *r;
+  struct frame *f;
+  int horflag
+    /* HORFLAG is 1 when we split side-by-side, 0 otherwise.  */
+    = EQ (side, Qt) || EQ (side, Qleft) || EQ (side, Qright);
+  int do_nest = 0;
+
+  CHECK_WINDOW (old);
+  o = XWINDOW (old);
+  frame = WINDOW_FRAME (o);
+  f = XFRAME (frame);
 
-  /* Give up if this window cannot be resized.  */
-  if (window_fixed_size_p (XWINDOW (window), horiz_flag, 1))
-    error ("Window is not resizable");
+  CHECK_NUMBER (total_size);
+
+  /* Set do_nest to 1 if we have to make a new parent window.  We do
+     that if either `window-nest' is non-nil, or OLD has no parent, or
+     OLD is ortho-combined.  */
+  do_nest =
+    !NILP (Vwindow_nest)
+    || NILP (o->parent)
+    || NILP (horflag
+             ? (XWINDOW (o->parent)->hchild)
+             : (XWINDOW (o->parent)->vchild));
+
+  /* We need a live reference window to initialize some parameters.  */
+  if (WINDOW_LIVE_P (old))
+    /* OLD is live, use it as reference window.  */
+    reference = old;
+  else
+    /* Use the frame's selected window as reference window.  */
+    reference = FRAME_SELECTED_WINDOW (f);
+  r = XWINDOW (reference);
 
-  while (1)
+  /* The following bugs are caught by `split-window'.  */
+  if (MINI_WINDOW_P (o))
+    error ("Attempt to split minibuffer window");
+  else if (XINT (total_size) < (horflag ? 2 : 1))
+    error ("Size of new window too small (after split)");
+  else if (!do_nest && !NILP (Vwindow_splits))
+    /* `window-splits' non-nil means try to resize OLD's siblings
+       proportionally.  */
+    {
+      p = XWINDOW (o->parent);
+      /* Temporarily pretend we split the parent window.  */
+      XSETINT (p->new_total,
+               XINT (horflag ? p->total_cols : p->total_lines)
+               - XINT (total_size));
+      if (!resize_window_check (p, horflag))
+        error ("Window sizes don't fit");
+      else
+        /* Undo the temporary pretension.  */
+        p->new_total = horflag ? p->total_cols : p->total_lines;
+    }
+  else
     {
-      Lisp_Object first_parallel = Qnil;
-
-      if (NILP (window))
-        {
-          /* This happens if WINDOW on the previous iteration was
-             at top level of the window tree.  */
-          Fset_window_configuration (old_config);
-          error ("Specified window edge is fixed");
-        }
+      if (!resize_window_check (o, horflag))
+        error ("Resizing old window failed");
+      else if (XINT (total_size) + XINT (o->new_total)
+               != XINT (horflag ? o->total_cols : o->total_lines))
+        error ("Sum of sizes of old and new window don't fit");
+    }
+
+  /* This is our point of no return. */
+  if (do_nest)
+    {
+      /* Save the old value of o->normal_cols/lines.  It gets corrupted
+         by make_parent_window and we need it below for assigning it to
+         p->new_normal.  */
+      Lisp_Object new_normal = horflag ? o->normal_cols : o->normal_lines;
+
+      make_parent_window (old, horflag);
+      p = XWINDOW (o->parent);
+      /* Store value of `window-nest' in new parent's nest slot.  */
+      p->nest = Vwindow_nest;
+      /* Have PARENT inherit splits slot value from OLD.  */
+      p->splits = o->splits;
+      /* Store value of `window-splits' in OLD's splits slot.  */
+      o->splits = Vwindow_splits;
+      /* These get applied below.  */
+      p->new_total = horflag ? o->total_cols : o->total_lines;
+      p->new_normal = new_normal;
+    }
+  else
+    p = XWINDOW (o->parent);
 
-      p = XWINDOW (window);
-      parent = p->parent;
+  windows_or_buffers_changed++;
+  FRAME_WINDOW_SIZES_CHANGED (f) = 1;
+  new = make_window ();
+  n = XWINDOW (new);
+  n->frame = frame;
+  n->parent = o->parent;
+  n->vchild = n->hchild = Qnil;
 
-      /* See if this level has windows in parallel in the specified
-         direction.  If so, set FIRST_PARALLEL to the first one.  */
-      if (horiz_flag)
-        {
-          if (! NILP (parent) && !NILP (XWINDOW (parent)->vchild))
-            first_parallel = XWINDOW (parent)->vchild;
-          else if (NILP (parent) && !NILP (p->next))
-            {
-              /* Handle the vertical chain of main window and minibuffer
-                 which has no parent.  */
-              first_parallel = window;
-              while (! NILP (XWINDOW (first_parallel)->prev))
-                first_parallel = XWINDOW (first_parallel)->prev;
-            }
-        }
+  if (EQ (side, Qabove) || EQ (side, Qleft))
+    {
+      n->prev = o->prev;
+      if (NILP (n->prev))
+        if (horflag)
+          p->hchild = new;
+        else
+          p->vchild = new;
       else
-        {
-          if (! NILP (parent) && !NILP (XWINDOW (parent)->hchild))
-            first_parallel = XWINDOW (parent)->hchild;
-        }
-
-      /* If this level's succession is in the desired dimension,
-         and this window is the last one, and there is no higher level,
-         its trailing edge is fixed.  */
-      if (NILP (XWINDOW (window)->next) && NILP (first_parallel)
-          && NILP (parent))
-        {
-          Fset_window_configuration (old_config);
-          error ("Specified window edge is fixed");
-        }
-
-      /* Don't make this window too small.  */
-      if (XINT (CURSIZE (window)) + delta
-          < window_min_size_2 (XWINDOW (window), horiz_flag, 0))
-        {
-          Fset_window_configuration (old_config);
-          error ("Cannot adjust window size as specified");
-        }
+        XWINDOW (n->prev)->next = new;
+      n->next = old;
+      o->prev = new;
+    }
+  else
+    {
+      n->next = o->next;
+      if (!NILP (n->next))
+        XWINDOW (n->next)->prev = new;
+      n->prev = old;
+      o->next = new;
+    }
 
-      /* Clear out some redisplay caches.  */
-      XSETFASTINT (p->last_modified, 0);
-      XSETFASTINT (p->last_overlay_modified, 0);
+  n->buffer = Qt;
+  n->window_end_valid = Qnil;
+  memset (&n->last_cursor, 0, sizeof n->last_cursor);
 
-      /* Adjust this window's edge.  */
-      XSETINT (CURSIZE (window),
-               XINT (CURSIZE (window)) + delta);
+  /* Get special geometry settings from reference window.  */
+  n->left_margin_cols = r->left_margin_cols;
+  n->right_margin_cols = r->right_margin_cols;
+  n->left_fringe_width = r->left_fringe_width;
+  n->right_fringe_width = r->right_fringe_width;
+  n->fringes_outside_margins = r->fringes_outside_margins;
+  n->scroll_bar_width = r->scroll_bar_width;
+  n->vertical_scroll_bar_type = r->vertical_scroll_bar_type;
 
-      /* If this window has following siblings in the desired dimension,
-         make them smaller, and exit the loop.
+  /* Store `window-splits' in NEW's splits slot.  */
+  n->splits = Vwindow_splits;
 
-         (If we reach the top of the tree and can never do this,
-         we will fail and report an error, above.)  */
-      if (NILP (first_parallel))
-        {
-          if (!NILP (p->next))
-            {
-              /* This may happen for the minibuffer.  In that case
-                 the window_deletion_count check below does not work.  */
-              if (XINT (CURSIZE (p->next)) - delta <= 0)
-                {
-                  Fset_window_configuration (old_config);
-                  error ("Cannot adjust window size as specified");
-                }
-
-              XSETINT (CURBEG (p->next),
-                       XINT (CURBEG (p->next)) + delta);
-              size_window (p->next, XINT (CURSIZE (p->next)) - delta,
-                           horiz_flag, 0, 1, 0);
-              break;
-            }
-        }
-      else
-        /* Here we have a chain of parallel siblings, in the other dimension.
-           Change the size of the other siblings.  */
-        for (child = first_parallel;
-             ! NILP (child);
-             child = XWINDOW (child)->next)
-          if (! EQ (child, window))
-            size_window (child, XINT (CURSIZE (child)) + delta,
-                         horiz_flag, 0, 0, 1);
-
-      window = parent;
+  /* Directly assign orthogonal coordinates and sizes.  */
+  if (horflag)
+    {
+      n->top_line = o->top_line;
+      n->total_lines = o->total_lines;
     }
-
-  /* If we made a window so small it got deleted,
-     we failed.  Report failure.  */
-  if (delcount != window_deletion_count)
+  else
     {
-      Fset_window_configuration (old_config);
-      error ("Cannot adjust window size as specified");
+      n->left_col = o->left_col;
+      n->total_cols = o->total_cols;
     }
 
-  /* Adjust glyph matrices. */
-  adjust_glyphs (XFRAME (WINDOW_FRAME (XWINDOW (window))));
-}
-
-#undef CURBEG
-#undef CURSIZE
-
-DEFUN ("adjust-window-trailing-edge", Fadjust_window_trailing_edge,
-       Sadjust_window_trailing_edge, 3, 3, 0,
-       doc: /* Adjust the bottom or right edge of WINDOW by DELTA.
-If HORIZONTAL is non-nil, that means adjust the width, moving the right edge.
-Otherwise, adjust the height, moving the bottom edge.
+  /* Iso-coordinates and sizes are assigned by resize_window_apply,
+     get them ready here.  */
+  n->new_total = total_size;
+  n->new_normal = normal_size;
 
-Following siblings of the selected window are resized to fulfill
-the size request.  If they become too small in the process, they
-are not deleted; instead, we signal an error.  */)
-  (Lisp_Object window, Lisp_Object delta, Lisp_Object horizontal)
-{
-  CHECK_NUMBER (delta);
-  if (NILP (window))
-    window = selected_window;
-  adjust_window_trailing_edge (window, XINT (delta), !NILP (horizontal));
-
-  run_window_configuration_change_hook
-    (XFRAME (WINDOW_FRAME (XWINDOW (window))));
+  BLOCK_INPUT;
+  resize_window_apply (p, horflag);
+  adjust_glyphs (f);
+  /* Set buffer of NEW to buffer of reference window.  Don't run
+     any hooks.  */
+  set_window_buffer (new, r->buffer, 0, 1);
+  UNBLOCK_INPUT;
 
-  return Qnil;
+  /* Maybe we should run the scroll functions in Elisp (which already
+     runs the configuration change hook).  */
+  if (! NILP (Vwindow_scroll_functions))
+    run_hook_with_args_2 (Qwindow_scroll_functions, new,
+                          Fmarker_position (n->start));
+  /* Return NEW.  */
+  return new;
 }
 
 
-
-/***********************************************************************
-                        Resizing Mini-Windows
- ***********************************************************************/
-
-static void shrink_window_lowest_first (struct window *, int);
-
-enum save_restore_action
+DEFUN ("delete-window-internal", Fdelete_window_internal, Sdelete_window_internal, 1, 1, 0,
+       doc: /* Remove WINDOW from its frame.
+WINDOW defaults to the selected window.  Return nil. Signal an error
+when WINDOW is the only window on its frame.  */)
+     (register Lisp_Object window)
 {
-    CHECK_ORIG_SIZES,
-    SAVE_ORIG_SIZES,
-    RESTORE_ORIG_SIZES
-};
-
-static int save_restore_orig_size (struct window *,
-                                   enum save_restore_action);
-
-/* Shrink windows rooted in window W to HEIGHT.  Take the space needed
-   from lowest windows first.  */
+  register Lisp_Object parent, sibling, frame, root;
+  struct window *w, *p, *s, *r;
+  struct frame *f;
+  int horflag;
+  int before_sibling = 0;
 
-static void
-shrink_window_lowest_first (struct window *w, int height)
-{
-  struct window *c;
-  Lisp_Object child;
-  int old_height;
+  w = decode_any_window (window);
+  XSETWINDOW (window, w);
+  if (NILP (w->buffer) && NILP (w->hchild) && NILP (w->vchild))
+    /* It's a no-op to delete an already deleted window.  */
+    return Qnil;
 
-  xassert (!MINI_WINDOW_P (w));
+  parent = w->parent;
+  if (NILP (parent))
+    /* Never delete a minibuffer or frame root window.  */
+    error ("Attempt to delete minibuffer or sole ordinary window");
+  else if (NILP (w->prev) && NILP (w->next))
+    /* Rather bow out here, this case should be handled on the Elisp
+       level.  */
+    error ("Attempt to delete sole window of parent");
 
-  /* Set redisplay hints.  */
-  XSETFASTINT (w->last_modified, 0);
-  XSETFASTINT (w->last_overlay_modified, 0);
-  windows_or_buffers_changed++;
-  FRAME_WINDOW_SIZES_CHANGED (XFRAME (WINDOW_FRAME (w))) = 1;
+  p = XWINDOW (parent);
+  horflag = NILP (p->vchild);
 
-  old_height = XFASTINT (w->total_lines);
-  XSETFASTINT (w->total_lines, height);
+  frame = WINDOW_FRAME (w);
+  f = XFRAME (frame);
 
-  if (!NILP (w->hchild))
+  root = FRAME_ROOT_WINDOW (f);
+  r = XWINDOW (root);
+
+  /* Unlink WINDOW from window tree.  */
+  if (NILP (w->prev))
+    /* Get SIBLING below (on the right of) WINDOW.  */
+    {
+      /* before_sibling 1 means WINDOW is the first child of its
+         parent and thus before the sibling.  */
+      before_sibling = 1;
+      sibling = w->next;
+      s = XWINDOW (sibling);
+      s->prev = Qnil;
+      if (horflag)
+        p->hchild = sibling;
+      else
+        p->vchild = sibling;
+    }
+  else
+    /* Get SIBLING above (on the left of) WINDOW.  */
     {
-      for (child = w->hchild; !NILP (child); child = c->next)
-        {
-          c = XWINDOW (child);
-          c->top_line = w->top_line;
-          shrink_window_lowest_first (c, height);
-        }
+      sibling = w->prev;
+      s = XWINDOW (sibling);
+      s->next = w->next;
+      if (!NILP (s->next))
+        XWINDOW (s->next)->prev = sibling;
     }
-  else if (!NILP (w->vchild))
+
+  if (resize_window_check (r, horflag)
+      && EQ (r->new_total, (horflag ? r->total_cols : r->total_lines)))
+    /* We can delete WINDOW now.  */
     {
-      Lisp_Object last_child;
-      int delta = old_height - height;
-      int last_top;
+      /* Block input.  */
+      BLOCK_INPUT;
+      resize_window_apply (p, horflag);
 
-      last_child = Qnil;
+      windows_or_buffers_changed++;
+      Vwindow_list = Qnil;
+      FRAME_WINDOW_SIZES_CHANGED (f) = 1;
 
-      /* Find the last child.  We are taking space from lowest windows
-         first, so we iterate over children from the last child
-         backwards.  */
-      for (child = w->vchild; WINDOWP (child); child = XWINDOW (child)->next)
-        last_child = child;
+      w->next = Qnil;  /* Don't delete w->next too.  */
+      free_window_matrices (w);
 
-      /* Size children down to their safe heights.  */
-      for (child = last_child; delta && !NILP (child); child = c->prev)
+      if (!NILP (w->vchild))
         {
-          int this_one;
-
-          c = XWINDOW (child);
-          this_one = XFASTINT (c->total_lines) - window_min_size_1 (c, 0, 1);
-
-          if (this_one > delta)
-            this_one = delta;
-
-          shrink_window_lowest_first (c, XFASTINT (c->total_lines) - this_one);
-          delta -= this_one;
+          delete_all_subwindows (w->vchild);
+          w->vchild = Qnil;
         }
-
-      /* Compute new positions.  */
-      last_top = XINT (w->top_line);
-      for (child = w->vchild; !NILP (child); child = c->next)
+      else if (!NILP (w->hchild))
         {
-          c = XWINDOW (child);
-          c->top_line = make_number (last_top);
-          shrink_window_lowest_first (c, XFASTINT (c->total_lines));
-          last_top += XFASTINT (c->total_lines);
+          delete_all_subwindows (w->hchild);
+          w->hchild = Qnil;
+        }
+      else if (!NILP (w->buffer))
+        {
+          unshow_buffer (w);
+          unchain_marker (XMARKER (w->pointm));
+          unchain_marker (XMARKER (w->start));
+          w->buffer = Qnil;
         }
-    }
-}
 
+      if (NILP (s->prev) && NILP (s->next))
+          /* A matrjoshka where SIBLING has become the only child of
+             PARENT.  */
+        {
+          /* Put SIBLING into PARENT's place.  */
+          replace_window (parent, sibling, 0);
+          /* Have SIBLING inherit the following three slot values from
+             PARENT (the nest slot is not inherited).  */
+          s->normal_cols = p->normal_cols;
+          s->normal_lines = p->normal_lines;
+          s->splits = p->splits;
+          /* Mark PARENT as deleted.  */
+          p->vchild = p->hchild = Qnil;
+          /* Try to merge SIBLING into its new parent.  */
+          recombine_windows (sibling);
+        }
 
-/* Save, restore, or check positions and sizes in the window tree
-   rooted at W.  ACTION says what to do.
+      adjust_glyphs (f);
 
-   If ACTION is CHECK_ORIG_SIZES, check if orig_top_line and
-   orig_total_lines members are valid for all windows in the window
-   tree.  Value is non-zero if they are valid.
+      if (!WINDOW_LIVE_P (FRAME_SELECTED_WINDOW (f)))
+        /* We deleted the frame's selected window.  */
+        {
+          /* Use the frame's first window as fallback ...  */
+          Lisp_Object new_selected_window = Fframe_first_window (frame);
+          /* ... but preferably use its most recently used window.  */
+          Lisp_Object mru_window;
+
+          /* `get-mru-window' might fail for some reason so play it safe
+          - promote the first window _without recording it_ first.  */
+          if (EQ (FRAME_SELECTED_WINDOW (f), selected_window))
+            Fselect_window (new_selected_window, Qt);
+          else
+            FRAME_SELECTED_WINDOW (f) = new_selected_window;
 
-   If ACTION is SAVE_ORIG_SIZES, save members top and height in
-   orig_top_line and orig_total_lines for all windows in the tree.
+          UNBLOCK_INPUT;
 
-   If ACTION is RESTORE_ORIG_SIZES, restore top and height from values
-   stored in orig_top_line and orig_total_lines for all windows.  */
+          /* Now look whether `get-mru-window' gets us something.  */
+          mru_window = call1 (Qget_mru_window, frame);
+          if (WINDOW_LIVE_P (mru_window)
+              && EQ (XWINDOW (mru_window)->frame, frame))
+            new_selected_window = mru_window;
 
-static int
-save_restore_orig_size (struct window *w, enum save_restore_action action)
-{
-  int success_p = 1;
+          /* If all ended up well, we now promote the mru window.  */
+          if (EQ (FRAME_SELECTED_WINDOW (f), selected_window))
+            Fselect_window (new_selected_window, Qnil);
+          else
+            FRAME_SELECTED_WINDOW (f) = new_selected_window;
+        }
+      else
+        UNBLOCK_INPUT;
 
-  while (w)
+      /* Must be run by the caller:
+         run_window_configuration_change_hook (f);  */
+    }
+  else
+    /* We failed: Relink WINDOW into window tree.  */
     {
-      if (!NILP (w->hchild))
-        {
-          if (!save_restore_orig_size (XWINDOW (w->hchild), action))
-            success_p = 0;
-        }
-      else if (!NILP (w->vchild))
+      if (before_sibling)
         {
-          if (!save_restore_orig_size (XWINDOW (w->vchild), action))
-            success_p = 0;
+          s->prev = window;
+          if (horflag)
+            p->hchild = window;
+          else
+            p->vchild = window;
         }
-
-      switch (action)
+      else
         {
-        case CHECK_ORIG_SIZES:
-          if (!INTEGERP (w->orig_top_line) || !INTEGERP (w->orig_total_lines))
-            return 0;
-          break;
-
-        case SAVE_ORIG_SIZES:
-          w->orig_top_line = w->top_line;
-          w->orig_total_lines = w->total_lines;
-          XSETFASTINT (w->last_modified, 0);
-          XSETFASTINT (w->last_overlay_modified, 0);
-          break;
-
-        case RESTORE_ORIG_SIZES:
-          xassert (INTEGERP (w->orig_top_line) && INTEGERP (w->orig_total_lines));
-          w->top_line = w->orig_top_line;
-          w->total_lines = w->orig_total_lines;
-          w->orig_total_lines = w->orig_top_line = Qnil;
-          XSETFASTINT (w->last_modified, 0);
-          XSETFASTINT (w->last_overlay_modified, 0);
-          break;
-
-        default:
-          abort ();
+          s->next = window;
+          if (!NILP (w->next))
+            XWINDOW (w->next)->prev = window;
         }
-
-      w = NILP (w->next) ? NULL : XWINDOW (w->next);
+      error ("Deletion failed");
     }
 
-  return success_p;
+  return Qnil;
 }
+
+/***********************************************************************
+                        Resizing Mini-Windows
+ ***********************************************************************/
 
-
-/* Grow mini-window W by DELTA lines, DELTA >= 0, or as much as we can
-   without deleting other windows.  */
-
+/* Grow mini-window W by DELTA lines, DELTA >= 0, or as much as we
+   can.  */
 void
 grow_mini_window (struct window *w, int delta)
 {
   struct frame *f = XFRAME (w->frame);
-  struct window *root;
+  struct window *r;
+  Lisp_Object root, value;
 
   xassert (MINI_WINDOW_P (w));
-  /* Commenting out the following assertion goes against the stated interface
-     of the function, but it currently does not seem to do anything useful.
-     See discussion of this issue in the thread for bug#4534.
-     xassert (delta >= 0); */
+  xassert (delta >= 0);
 
-  /* Compute how much we can enlarge the mini-window without deleting
-     other windows.  */
-  root = XWINDOW (FRAME_ROOT_WINDOW (f));
-  if (delta > 0)
+  root = FRAME_ROOT_WINDOW (f);
+  r = XWINDOW (root);
+  value = call2 (Qresize_root_window_vertically, root, make_number (- delta));
+  if (INTEGERP (value) && resize_window_check (r, 0))
     {
-      int min_height = window_min_size (root, 0, 0, 0, 0);
-      if (XFASTINT (root->total_lines) - delta < min_height)
-        /* Note that the root window may already be smaller than
-           min_height.  */
-        delta = max (0, XFASTINT (root->total_lines) - min_height);
-    }
-
-  if (delta)
-    {
-      /* Save original window sizes and positions, if not already done.  */
-      if (!save_restore_orig_size (root, CHECK_ORIG_SIZES))
-        save_restore_orig_size (root, SAVE_ORIG_SIZES);
-
-      /* Shrink other windows.  */
-      shrink_window_lowest_first (root, XFASTINT (root->total_lines) - delta);
+      BLOCK_INPUT;
+      resize_window_apply (r, 0);
 
       /* Grow the mini-window.  */
-      w->top_line = make_number (XFASTINT (root->top_line) + XFASTINT (root->total_lines));
-      w->total_lines = make_number (XFASTINT (w->total_lines) + delta);
+      XSETFASTINT (w->top_line, XFASTINT (r->top_line) + XFASTINT (r->total_lines));
+      XSETFASTINT (w->total_lines, XFASTINT (w->total_lines) - XINT (value));
       XSETFASTINT (w->last_modified, 0);
       XSETFASTINT (w->last_overlay_modified, 0);
 
       adjust_glyphs (f);
+      UNBLOCK_INPUT;
     }
 }
 
 
-/* Shrink mini-window W.  If there is recorded info about window sizes
-   before a call to grow_mini_window, restore recorded window sizes.
-   Otherwise, if the mini-window is higher than 1 line, resize it to 1
-   line.  */
-
+/* Shrink mini-window W.  */
 void
 shrink_mini_window (struct window *w)
 {
   struct frame *f = XFRAME (w->frame);
-  struct window *root = XWINDOW (FRAME_ROOT_WINDOW (f));
+  struct window *r;
+  Lisp_Object root, value;
+  EMACS_INT size;
 
-  if (save_restore_orig_size (root, CHECK_ORIG_SIZES))
-    {
-      save_restore_orig_size (root, RESTORE_ORIG_SIZES);
-      adjust_glyphs (f);
-      FRAME_WINDOW_SIZES_CHANGED (f) = 1;
-      windows_or_buffers_changed = 1;
-    }
-  else if (XFASTINT (w->total_lines) > 1)
+  xassert (MINI_WINDOW_P (w));
+
+  size = XINT (w->total_lines);
+  if (size > 1)
     {
-      /* Distribute the additional lines of the mini-window
-         among the other windows.  */
-      Lisp_Object window;
-      XSETWINDOW (window, w);
-      enlarge_window (window, 1 - XFASTINT (w->total_lines), 0);
+      root = FRAME_ROOT_WINDOW (f);
+      r = XWINDOW (root);
+      value = call2 (Qresize_root_window_vertically,
+                     root, make_number (size - 1));
+      if (INTEGERP (value) && resize_window_check (r, 0))
+        {
+          BLOCK_INPUT;
+          resize_window_apply (r, 0);
+
+          /* Shrink the mini-window.  */
+          XSETFASTINT (w->top_line, XFASTINT (r->top_line) + XFASTINT (r->total_lines));
+          XSETFASTINT (w->total_lines, 1);
+
+          XSETFASTINT (w->last_modified, 0);
+          XSETFASTINT (w->last_overlay_modified, 0);
+
+          adjust_glyphs (f);
+          UNBLOCK_INPUT;
+        }
+      /* If the above failed for whatever strange reason we must make a
+         one window frame here.  The same routine will be needed when
+         shrinking the frame (and probably when making the initial
+         *scratch* window).  For the moment leave things as they are.  */
     }
 }
 
+DEFUN ("resize-mini-window-internal", Fresize_mini_window_internal, Sresize_mini_window_internal, 1, 1, 0,
+       doc: /* Resize minibuffer window WINDOW.  */)
+     (Lisp_Object window)
+{
+  struct window *w = XWINDOW (window);
+  struct window *r;
+  struct frame *f;
+  int height;
 
+  CHECK_WINDOW (window);
+  f = XFRAME (w->frame);
+
+  if (!EQ (FRAME_MINIBUF_WINDOW (XFRAME (w->frame)), window))
+    error ("Not a valid minibuffer window");
+  else if (FRAME_MINIBUF_ONLY_P (f))
+    error ("Cannot resize a minibuffer-only frame");
+
+  r = XWINDOW (FRAME_ROOT_WINDOW (f));
+  height = XINT (r->total_lines) + XINT (w->total_lines);
+  if (resize_window_check (r, 0)
+      && XINT (w->new_total) > 0
+      && height == XINT (r->new_total) + XINT (w->new_total))
+    {
+      BLOCK_INPUT;
+      resize_window_apply (r, 0);
+
+      w->total_lines = w->new_total;
+      XSETFASTINT (w->top_line, XINT (r->top_line) + XINT (r->total_lines));
+
+      windows_or_buffers_changed++;
+      FRAME_WINDOW_SIZES_CHANGED (f) = 1;
+      adjust_glyphs (f);
+      UNBLOCK_INPUT;
+
+      run_window_configuration_change_hook (f);
+      return Qt;
+    }
+  else error ("Failed to resize minibuffer window");
+}
+
 
 /* Mark window cursors off for all windows in the window tree rooted
    at W by setting their phys_cursor_on_p flag to zero.  Called from
@@ -6190,11 +5476,9 @@ struct saved_window
   Lisp_Object parent, prev;
   Lisp_Object start_at_line_beg;
   Lisp_Object display_table;
-  Lisp_Object orig_top_line, orig_total_lines;
   Lisp_Object left_margin_cols, right_margin_cols;
   Lisp_Object left_fringe_width, right_fringe_width, fringes_outside_margins;
-  Lisp_Object scroll_bar_width, vertical_scroll_bar_type;
-  Lisp_Object dedicated, resize_proportionally;
+  Lisp_Object scroll_bar_width, vertical_scroll_bar_type, dedicated;
   Lisp_Object splits, nest, window_parameters;
 };
 
@@ -6414,8 +5698,6 @@ the return value is nil.  Otherwise the value is t.  */)
           w->hscroll = p->hscroll;
           w->min_hscroll = p->min_hscroll;
           w->display_table = p->display_table;
-          w->orig_top_line = p->orig_top_line;
-          w->orig_total_lines = p->orig_total_lines;
           w->left_margin_cols = p->left_margin_cols;
           w->right_margin_cols = p->right_margin_cols;
           w->left_fringe_width = p->left_fringe_width;
@@ -6427,7 +5709,6 @@ the return value is nil.  Otherwise the value is t.  */)
           w->splits = p->splits;
           w->nest = p->nest;
           w->window_parameters = p->window_parameters;
-          w->resize_proportionally = p->resize_proportionally;
           XSETFASTINT (w->last_modified, 0);
           XSETFASTINT (w->last_overlay_modified, 0);
 
@@ -6556,6 +5837,7 @@ the return value is nil.  Otherwise the value is t.  */)
   return (FRAME_LIVE_P (f) ? Qt : Qnil);
 }
 
+
 /* Delete all subwindows reachable via the next, vchild, and hchild
    slots of WINDOW.  */
 void
@@ -6608,7 +5890,6 @@ count_windows (register struct window *window)
 
 /* Fill vector FLAT with leaf windows under W, starting at index I.
    Value is last index + 1.  */
-
 static int
 get_leaf_windows (struct window *w, struct window **flat, int i)
 {
@@ -6631,7 +5912,6 @@ get_leaf_windows (struct window *w, struct window **flat, int i)
 /* Return a pointer to the glyph W's physical cursor is on.  Value is
    null if W's current matrix is invalid, so that no meaningfull glyph
    can be returned.  */
-
 struct glyph *
 get_phys_cursor_glyph (struct window *w)
 {
@@ -6676,8 +5956,6 @@ save_window_save (Lisp_Object window, struct Lisp_Vector *vector, int i)
       p->hscroll = w->hscroll;
       p->min_hscroll = w->min_hscroll;
       p->display_table = w->display_table;
-      p->orig_top_line = w->orig_top_line;
-      p->orig_total_lines = w->orig_total_lines;
       p->left_margin_cols = w->left_margin_cols;
       p->right_margin_cols = w->right_margin_cols;
       p->left_fringe_width = w->left_fringe_width;
@@ -6688,7 +5966,6 @@ save_window_save (Lisp_Object window, struct Lisp_Vector *vector, int i)
       p->dedicated = w->dedicated;
       p->splits = w->splits;
       p->nest = w->nest;
-      p->resize_proportionally = w->resize_proportionally;
       p->window_parameters = w->window_parameters;
       if (!NILP (w->buffer))
         {
@@ -7382,10 +6659,6 @@ syms_of_window (void)
   Fput (Qscroll_up, Qscroll_command, Qt);
   Fput (Qscroll_down, Qscroll_command, Qt);
 
-  Qwindow_size_fixed = intern_c_string ("window-size-fixed");
-  staticpro (&Qwindow_size_fixed);
-  Fset (Qwindow_size_fixed, Qnil);
-
   staticpro (&Qwindow_configuration_change_hook);
   Qwindow_configuration_change_hook
     = intern_c_string ("window-configuration-change-hook");
@@ -7478,24 +6751,6 @@ is displayed in the `mode-line' face.  */);
               doc: /* *Number of lines of continuity when scrolling by screenfuls.  */);
   next_screen_context_lines = 2;
 
-  DEFVAR_INT ("window-min-height", window_min_height,
-              doc: /* Allow deleting windows less than this tall.
-The value is measured in line units.  If a window wants a modeline it
-is counted as one line.
-
-Emacs honors settings of this variable when enlarging or shrinking
-windows vertically.  A value less than 1 is invalid.  */);
-  window_min_height = 4;
-
-  DEFVAR_INT ("window-min-width", window_min_width,
-              doc: /* Allow deleting windows less than this wide.
-The value is measured in characters and includes any fringes or
-the scrollbar.
-
-Emacs honors settings of this variable when enlarging or shrinking
-windows horizontally.  A value less than 2 is invalid.  */);
-  window_min_width = 10;
-
   DEFVAR_LISP ("scroll-preserve-screen-position",
                Vscroll_preserve_screen_position,
                doc: /* *Controls if scroll commands move point to keep its screen position unchanged.
@@ -7527,6 +6782,41 @@ will redraw the entire frame; the special value `tty' causes the
 frame to be redrawn only if it is a tty frame.  */);
   Vrecenter_redisplay = Qtty;
 
+  DEFVAR_LISP ("window-splits", Vwindow_splits,
+               doc: /* Non-nil means splitting windows is handled specially.
+If this variable is nil, splitting a window gets the entire screen space
+for displaying the new window from the window to split.  If this
+variable is non-nil, splitting a window may resize all windows in the
+same combination.  This also allows to split a window that is otherwise
+too small or of fixed size.
+
+The value of this variable is also assigned to the split status of the
+new window and, provided the old and new window form a new combination,
+to the window that was split as well.  The split status of a window can
+be retrieved with the function `window-splits' and altered by the
+function `set-window-splits'.
+
+If the value of the variable `window-nest' is non-nil, the space for the
+new window is exclusively taken from the window that shall be split, but
+the split status of the window that is split as well as that of the new
+window are still set to the value of this variable.  */);
+  Vwindow_splits = Qnil;
+
+  DEFVAR_LISP ("window-nest", Vwindow_nest,
+               doc: /* Non-nil means splitting a window makes a new parent window.
+If this variable is nil, splitting a window will create a new parent
+window only if the window has no parent window or the window shall
+become a combination orthogonal to the one it it is part of.
+
+If this variable is non-nil, splitting a window always creates a new
+parent window.  If all splits behave this way, each frame's window tree
+is a binary tree and every window but the frame's root window has
+exactly one sibling.
+
+The value of this variable is also assigned to the nest status of the
+new parent window.  The nest status of a window can be retrieved via the
+function `window-nest' and altered by the function `set-window-nest'.  */);
+  Vwindow_nest = Qnil;
 
   defsubr (&Sselected_window);
   defsubr (&Sminibuffer_window);
@@ -7560,6 +6850,7 @@ frame to be redrawn only if it is a tty frame.  */);
   defsubr (&Swindow_new_normal);
   defsubr (&Sset_window_new_total);
   defsubr (&Sset_window_new_normal);
+  defsubr (&Sresize_window_apply);
   defsubr (&Swindow_body_size);
   defsubr (&Swindow_hscroll);
   defsubr (&Sset_window_hscroll);
@@ -7586,19 +6877,18 @@ frame to be redrawn only if it is a tty frame.  */);
   defsubr (&Sprevious_window);
   defsubr (&Sother_window);
   defsubr (&Sget_buffer_window);
-  defsubr (&Sdelete_other_windows);
   defsubr (&Sdelete_windows_on);
   defsubr (&Sreplace_buffer_in_windows);
-  defsubr (&Sdelete_window);
+  defsubr (&Sdelete_other_windows_internal);
+  defsubr (&Sdelete_window_internal);
+  defsubr (&Sresize_mini_window_internal);
   defsubr (&Sset_window_buffer);
   defsubr (&Sset_window_clone_number);
+  defsubr (&Srun_window_configuration_change_hook);
   defsubr (&Sselect_window);
   defsubr (&Sforce_window_update);
   defsubr (&Stemp_output_buffer_show);
-  defsubr (&Ssplit_window);
-  defsubr (&Senlarge_window);
-  defsubr (&Sshrink_window);
-  defsubr (&Sadjust_window_trailing_edge);
+  defsubr (&Ssplit_window_internal);
   defsubr (&Sscroll_up);
   defsubr (&Sscroll_down);
   defsubr (&Sscroll_left);
@@ -7637,11 +6927,7 @@ frame to be redrawn only if it is a tty frame.  */);
 void
 keys_of_window (void)
 {
-  initial_define_key (control_x_map, '1', "delete-other-windows");
-  initial_define_key (control_x_map, '2', "split-window");
-  initial_define_key (control_x_map, '0', "delete-window");
   initial_define_key (control_x_map, 'o', "other-window");
-  initial_define_key (control_x_map, '^', "enlarge-window");
   initial_define_key (control_x_map, '<', "scroll-left");
   initial_define_key (control_x_map, '>', "scroll-right");
 
diff --git a/src/window.h b/src/window.h
index c33179de9ba..236464775d3 100644
--- a/src/window.h
+++ b/src/window.h
@@ -261,12 +261,6 @@ struct window
     /* If redisplay in this window goes beyond this buffer position,
        must run the redisplay-end-trigger-hook.  */
     Lisp_Object redisplay_end_trigger;
-    /* Non-nil means resizing windows will attempt to resize this window
-       proportionally.  */
-    Lisp_Object resize_proportionally;
-
-    /* Original window height and top before mini-window was enlarged. */
-    Lisp_Object orig_total_lines, orig_top_line;
 
     /* Non-nil means deleting or resizing this window distributes
        space among all windows in the same combination.  */
@@ -833,9 +827,6 @@ extern Lisp_Object make_window (void);
 extern Lisp_Object window_from_coordinates (struct frame *, int, int,
                                             enum window_part *, int);
 EXFUN (Fwindow_dedicated_p, 1);
-extern void set_window_height (Lisp_Object, int, int);
-extern void set_window_width (Lisp_Object, int, int);
-extern void change_window_heights (Lisp_Object, int);
 extern void delete_all_subwindows (Lisp_Object);
 extern void freeze_window_starts (struct frame *, int);
 extern void grow_mini_window (struct window *, int);
@@ -918,7 +909,6 @@ EXFUN (Fselected_window, 0);
 EXFUN (Fframe_root_window, 1);
 EXFUN (Fframe_first_window, 1);
 EXFUN (Fset_frame_selected_window, 3);
-EXFUN (Fdelete_window, 1);
 EXFUN (Fset_window_configuration, 1);
 EXFUN (Fcurrent_window_configuration, 1);
 extern int compare_window_configurations (Lisp_Object, Lisp_Object, int);
@@ -933,5 +923,11 @@ extern void init_window_once (void);
 extern void init_window (void);
 extern void syms_of_window (void);
 extern void keys_of_window (void);
+extern void resize_frame_windows (struct frame *, int, int);
+extern int resize_window_check (struct window *, int);
+extern Lisp_Object delete_deletable_window (Lisp_Object);
+extern Lisp_Object resize_root_window (Lisp_Object, Lisp_Object, Lisp_Object,
+                                       Lisp_Object);
+
 
 #endif /* not WINDOW_H_INCLUDED */
diff --git a/src/xdisp.c b/src/xdisp.c
index 02467c7bedd..65f6ddd3889 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -27115,31 +27115,27 @@ Its value should be an ASCII acronym string, `hex-code', `empty-box', or
 void
 init_xdisp (void)
 {
-  Lisp_Object root_window;
-  struct window *mini_w;
-
   current_header_line_height = current_mode_line_height = -1;
 
   CHARPOS (this_line_start_pos) = 0;
 
-  mini_w = XWINDOW (minibuf_window);
-  root_window = FRAME_ROOT_WINDOW (XFRAME (WINDOW_FRAME (mini_w)));
-  echo_area_window = minibuf_window;
-
   if (!noninteractive)
     {
-      struct frame *f = XFRAME (WINDOW_FRAME (XWINDOW (root_window)));
+      struct window *m = XWINDOW (minibuf_window);
+      Lisp_Object frame = m->frame;
+      struct frame *f = XFRAME (frame);
+      Lisp_Object root = FRAME_ROOT_WINDOW (f);
+      struct window *r = XWINDOW (root);
       int i;
 
-      XWINDOW (root_window)->top_line = make_number (FRAME_TOP_MARGIN (f));
-      set_window_height (root_window,
-                         FRAME_LINES (f) - 1 - FRAME_TOP_MARGIN (f),
-                         0);
-      mini_w->top_line = make_number (FRAME_LINES (f) - 1);
-      set_window_height (minibuf_window, 1, 0);
+      echo_area_window = minibuf_window;
 
-      XWINDOW (root_window)->total_cols = make_number (FRAME_COLS (f));
-      mini_w->total_cols = make_number (FRAME_COLS (f));
+      XSETFASTINT (r->top_line, FRAME_TOP_MARGIN (f));
+      XSETFASTINT (r->total_lines, FRAME_LINES (f) - 1 - FRAME_TOP_MARGIN (f));
+      XSETFASTINT (r->total_cols, FRAME_COLS (f));
+      XSETFASTINT (m->top_line, FRAME_LINES (f) - 1);
+      XSETFASTINT (m->total_lines, 1);
+      XSETFASTINT (m->total_cols, FRAME_COLS (f));
 
       scratch_glyph_row.glyphs[TEXT_AREA] = scratch_glyphs;
       scratch_glyph_row.glyphs[TEXT_AREA + 1]
diff --git a/src/xfns.c b/src/xfns.c
index 25fa05c0a6e..8417db7d6e5 100644
--- a/src/xfns.c
+++ b/src/xfns.c
@@ -1227,7 +1227,7 @@ x_set_menu_bar_lines (struct frame *f, Lisp_Object value, Lisp_Object oldval)
     }
 #else /* not USE_X_TOOLKIT && not USE_GTK */
   FRAME_MENU_BAR_LINES (f) = nlines;
-  change_window_heights (f->root_window, nlines - olines);
+  resize_frame_windows (f, FRAME_LINES (f), 0);
 
   /* If the menu bar height gets changed, the internal border below
      the top margin has to be cleared.  Also, if the menu bar gets
@@ -1266,6 +1266,7 @@ x_set_menu_bar_lines (struct frame *f, Lisp_Object value, Lisp_Object oldval)
     }
 #endif /* not USE_X_TOOLKIT && not USE_GTK */
   adjust_glyphs (f);
+  run_window_configuration_change_hook (f);
 }
 
 
@@ -1326,7 +1327,7 @@ x_set_tool_bar_lines (struct frame *f, Lisp_Object value, Lisp_Object oldval)
     }
 
   FRAME_TOOL_BAR_LINES (f) = nlines;
-  change_window_heights (root_window, delta);
+  resize_frame_windows (f, FRAME_LINES (f), 0);
   adjust_glyphs (f);
 
   /* We also have to make sure that the internal border at the top of
@@ -1362,6 +1363,9 @@ x_set_tool_bar_lines (struct frame *f, Lisp_Object value, Lisp_Object oldval)
       if (WINDOWP (f->tool_bar_window))
         clear_glyph_matrix (XWINDOW (f->tool_bar_window)->current_matrix);
     }
+
+    run_window_configuration_change_hook (f);
+
 }