More window code related fixes and documentation changes.

* window.c (Fother_window_for_scrolling): Check that
Vother_window_scroll_buffer is a buffer.
* window.el (fit-frame-to-buffer, fit-frame-to-buffer-margins):
Fix doc-strings.
(fit-frame-to-buffer): New argument ONLY.  Remove dependency on
fit-frame-to-buffer variable.  Fix doc-string.
(fit-window-to-buffer): Set ONLY argument in call of
fit-frame-to-buffer.  Fix doc-string.
* frames.texi (Size and Position): Rewrite entries for
`fit-frame-to-buffer' and `fit-frame-to-buffer-margins'.  Add
description for `fit-frame-to-buffer-sizes'.
* windows.texi (Resizing Windows): Add descriptions for
pixelwise resizing.  Add entries for `window-resize-pixelwise'
and `fit-window-to-buffer-horizontally'.  Rewrite
`fit-window-to-buffer' entry.

3 files changed, 112 insertions, 40 deletions

diff --git a/doc/lispref/ChangeLog b/doc/lispref/ChangeLog
index 5dfc5de3ce6..cac66f6e9e1 100644
--- a/doc/lispref/ChangeLog
+++ b/doc/lispref/ChangeLog
@@ -1,3 +1,13 @@
+2014-03-06  Martin Rudalics  <rudalics@gmx.at>
+
+        * frames.texi (Size and Position): Rewrite entries for
+        `fit-frame-to-buffer' and `fit-frame-to-buffer-margins'.  Add
+        description for `fit-frame-to-buffer-sizes'.
+        * windows.texi (Resizing Windows): Add descriptions for
+        pixelwise resizing.  Add entries for `window-resize-pixelwise'
+        and `fit-window-to-buffer-horizontally'.  Rewrite
+        `fit-window-to-buffer' entry.
+
 2014-03-06  Xue Fuqiao  <xfq@gnu.org>
 
         * internals.texi (Window Internals): Remove field `region_showing'.
diff --git a/doc/lispref/frames.texi b/doc/lispref/frames.texi
index 9ebc6c1adc2..166ec6d8dec 100644
--- a/doc/lispref/frames.texi
+++ b/doc/lispref/frames.texi
@@ -1180,19 +1180,48 @@ The argument @var{pretend} has the same meaning as in
 
 @c FIXME?  Belongs more in Emacs manual than here?
 @c But, e.g., fit-window-to-buffer is in this manual.
-@deffn Command fit-frame-to-buffer &optional frame max-height min-height
-This command adjusts the height of @var{frame} (the default is the
-selected frame) to fit its contents.  The optional arguments
-@var{max-height} and @var{min-height} specify the maximum and minimum
-new frame heights, respectively.
-
-@vindex fit-frame-to-buffer-bottom-margin
-The default minimum height corresponds to @code{window-min-height}.
-The default maximum height is the screen height below the current top
-position of the frame, minus any margin specified by the option
-@code{fit-frame-to-buffer-bottom-margin}.
+If you have a frame that displays only one window, you can fit that
+frame to its buffer using the command @code{fit-frame-to-buffer}.
+
+@deffn Command fit-frame-to-buffer &optional frame max-height min-height max-width min-width only
+This command adjusts the size of @var{frame} to display the contents of
+its buffer exactly.  @var{frame} can be any live frame and defaults to
+the selected one.  Fitting is done only if @var{frame}'s root window is
+live.  The arguments @var{max-height}, @var{min-height}, @var{max-width}
+and @var{min-width} specify bounds on the new total size of
+@var{frame}'s root window.  @var{min-height} and @var{min-width} default
+to the values of @code{window-min-height} and @code{window-min-width}
+respectively.
+
+If the optional argument @var{only} is @code{vertically}, this function
+may resize the frame vertically only.  If @var{only} is
+@code{horizontally}, it may resize the frame horizontally only.
 @end deffn
 
+The behavior of @code{fit-frame-to-buffer} can be controlled with the
+help of the two options listed next.
+
+@defopt fit-frame-to-buffer-margins
+This option can be used to specify margins around frames to be fit by
+@code{fit-frame-to-buffer}.  Such margins can be useful to avoid, for
+example, that such frames overlap the taskbar.
+
+It specifies the numbers of pixels to be left free on the left, above,
+the right, and below a frame that shall be fit.  The default specifies
+@code{nil} for each which means to use no margins.  The value specified
+here can be overridden for a specific frame by that frame's
+@code{fit-frame-to-buffer-margins} parameter, if present.
+@end defopt
+
+@defopt fit-frame-to-buffer-sizes
+This option specifies size boundaries for @code{fit-frame-to-buffer}.
+It specifies the total maximum and minimum lines and maximum and minimum
+columns of the root window of any frame that shall be fit to its buffer.
+If any of these values is non-@code{nil}, it overrides the corresponding
+argument of @code{fit-frame-to-buffer}.
+@end defopt
+
+
 @node Geometry
 @subsection Geometry
 
diff --git a/doc/lispref/windows.texi b/doc/lispref/windows.texi
index a0c59afbf28..3fa4117e52c 100644
--- a/doc/lispref/windows.texi
+++ b/doc/lispref/windows.texi
@@ -691,10 +691,9 @@ lines or columns.  If @var{delta} is non-zero, a return value of 0 means
 that the window cannot be resized.
 
 Normally, the variables @code{window-min-height} and
-@code{window-min-width} specify the smallest allowable window size.
-@xref{Change Window,, Deleting and Rearranging Windows, emacs, The GNU
-Emacs Manual}.  However, if the optional argument @var{ignore} is
-non-@code{nil}, this function ignores @code{window-min-height} and
+@code{window-min-width} specify the smallest allowable window size
+(@pxref{Window Sizes}).  However, if the optional argument @var{ignore}
+is non-@code{nil}, this function ignores @code{window-min-height} and
 @code{window-min-width}, as well as @code{window-size-fixed}.  Instead,
 it considers the minimum-height window to be one consisting of a header,
 a mode line and a bottom divider (if any), plus a text area one line
@@ -755,43 +754,73 @@ window is fixed-size), it may resize other windows.
 
 @cindex pixelwise, resizing windows
 @defopt window-resize-pixelwise
-If the value of this user option is non-@code{nil}, window resizing
-operations will be pixelwise.  This currently affects the following
-functions: @code{split-window}, @code{maximize-window},
-@code{minimize-window}, @code{fit-window-to-buffer} and
-@code{fit-frame-to-buffer}, and all functions that symmetrically
-resize a parent window.
+If the value of this option is non-@code{nil}, windows are resized in
+units of pixels.  This currently affects functions like
+@code{split-window} (@pxref{Splitting Windows}), @code{maximize-window},
+@code{minimize-window}, @code{fit-window-to-buffer},
+@code{shrink-window-if-larger-than-buffer} (all listed below) and
+@code{fit-frame-to-buffer} (@pxref{Size and Position}).
 
 Note that when a frame's pixel size is not a multiple of the frame's
 character size, at least one window may get resized pixelwise even if
-this option is nil.  The default value of this user option is
+this option is @code{nil}.  The default value of this option is
 @code{nil}.
 @end defopt
 
   The following commands resize windows in more specific ways.  When
 called interactively, they act on the selected window.
 
-@deffn Command fit-window-to-buffer &optional window max-height min-height override
-This command adjusts the height of @var{window} to fit the text in it.
-It returns non-@code{nil} if it was able to resize @var{window}, and
-@code{nil} otherwise.  If @var{window} is omitted or @code{nil}, it
-defaults to the selected window.  Otherwise, it should be a live
-window.
+@deffn Command fit-window-to-buffer &optional window max-height min-height max-width min-width
+This command adjusts the height or width of @var{window} to fit the text
+in it.  It returns non-@code{nil} if it was able to resize @var{window},
+and @code{nil} otherwise.  If @var{window} is omitted or @code{nil}, it
+defaults to the selected window.  Otherwise, it should be a live window.
+
+If @var{window} is part of a vertical combination, this function adjusts
+@var{window}'s height.  The new height is calculated from the actual
+height of the accessible portion of its buffer.  The optional argument
+@var{max-height}, if non-@code{nil}, specifies the maximum total height
+that this function can give @var{window}.  The optional argument
+@var{min-height}, if non-@code{nil}, specifies the minimum total height
+that it can give, which overrides the variable @code{window-min-height}.
+Both @var{max-height} and @var{min-height} are specified in lines and
+include mode and header line and a bottom divider, if any.
+
+If @var{window} is part of a horizontal combination and the value of the
+option @code{fit-window-to-buffer-horizontally} (see below) is
+non-@code{nil}, this function adjusts @var{window}'s height.  The new
+width of @var{window} is calculated from the maximum length of its
+buffer's lines that follow the current start position of @var{window}.
+The optional argument @var{max-width} specifies a maximum width and
+defaults to the width of @var{window}'s frame.  The optional argument
+@var{min-width} specifies a minimum width and defaults to
+@code{window-min-width}.  Both @var{max-width} and @var{min-width} are
+specified in columns and include fringes, margins and scrollbars, if
+any.
 
-The optional argument @var{max-height}, if non-@code{nil}, specifies
-the maximum total height that this function can give @var{window}.
-The optional argument @var{min-height}, if non-@code{nil}, specifies
-the minimum total height that it can give, which overrides the
-variable @code{window-min-height}.
+If the option @code{fit-frame-to-buffer} (see below) is non-@code{nil},
+this function will try to resize the frame of @var{window} to fit its
+contents by calling @code{fit-frame-to-buffer} (@pxref{Size and
+Position}).
+@end deffn
 
-If the optional argument @var{override} is non-@code{nil}, this
-function ignores any size restrictions imposed by
-@code{window-min-height} and @code{window-min-width}.
+@defopt fit-window-to-buffer-horizontally
+If this is non-@code{nil}, @code{fit-window-to-buffer} can resize
+windows horizontally.  If this is @code{nil} (the default)
+@code{fit-window-to-buffer} never resizes windows horizontally.  If this
+is @code{only}, it can resize windows horizontally only.  Any other
+value means @code{fit-window-to-buffer} can resize windows in both
+dimensions.
+@end defopt
 
-@vindex fit-frame-to-buffer
-If the option @code{fit-frame-to-buffer} is non-@code{nil}, this
-command may resize the frame to fit its contents.
-@end deffn
+@defopt fit-frame-to-buffer
+If this option is non-@code{nil}, @code{fit-window-to-buffer} can fit a
+frame to its buffer.  A frame is fit if and only if its root window is a
+live window and this option is non-@code{nil}.  If this is
+@code{horizontally}, frames are fit horizontally only.  If this is
+@code{vertically}, frames are fit vertically only.  Any other
+non-@code{nil} value means frames can be resized in both dimensions.
+@end defopt
 
 @deffn Command shrink-window-if-larger-than-buffer &optional window
 This command attempts to reduce @var{window}'s height as much as
@@ -804,8 +833,12 @@ it should be a live window.
 This command does nothing if the window is already too short to
 display all of its buffer, or if any of the buffer is scrolled
 off-screen, or if the window is the only live window in its frame.
+
+This command calls @code{fit-window-to-buffer} (see above) to do its
+work.
 @end deffn
 
+
 @cindex balancing window sizes
 @deffn Command balance-windows &optional window-or-frame
 This function balances windows in a way that gives more space to