Coverity fixes

[sxemacs] / src / ui / frame.c

/* Generic frame functions.
   Copyright (C) 1989, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
   Copyright (C) 1995, 1996 Ben Wing.
   Copyright (C) 1995 Sun Microsystems, Inc.

This file is part of SXEmacs

SXEmacs is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

SXEmacs is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>. */


/* Synched up with: FSF 19.30. */

/* This file has been Mule-ized. */

#include <config.h>
#include "lisp.h"

#include "buffer.h"             /* for Vbuffer_alist */
#include "console.h"
#define INCLUDE_EVENTS_H_PRIVATE_SPHERE
#include "events/events.h"
#include "extents.h"
#include "faces.h"
#include "frame.h"
#include "glyphs.h"
#include "gutter.h"
#include "menubar.h"
#include "redisplay.h"
#include "scrollbar.h"
#include "window.h"

Lisp_Object Vselect_frame_hook, Qselect_frame_hook;
Lisp_Object Vdeselect_frame_hook, Qdeselect_frame_hook;
Lisp_Object Vcreate_frame_hook, Qcreate_frame_hook;
Lisp_Object Vdelete_frame_hook, Qdelete_frame_hook;
Lisp_Object Vmouse_enter_frame_hook, Qmouse_enter_frame_hook;
Lisp_Object Vmouse_leave_frame_hook, Qmouse_leave_frame_hook;
Lisp_Object Vmap_frame_hook, Qmap_frame_hook;
Lisp_Object Vunmap_frame_hook, Qunmap_frame_hook;
int allow_deletion_of_last_visible_frame;
Lisp_Object Vadjust_frame_function;
Lisp_Object Vmouse_motion_handler;
Lisp_Object Vsynchronize_minibuffers;
Lisp_Object Qsynchronize_minibuffers;
Lisp_Object Qbuffer_predicate;
Lisp_Object Qmake_initial_minibuffer_frame;
Lisp_Object Qcustom_initialize_frame;

/* We declare all these frame properties here even though many of them
   are currently only used in frame-x.c, because we should generalize
   them. */

Lisp_Object Qminibuffer;
Lisp_Object Qunsplittable;
Lisp_Object Qinternal_border_width;
Lisp_Object Qtop_toolbar_shadow_color;
Lisp_Object Qbottom_toolbar_shadow_color;
Lisp_Object Qbackground_toolbar_color;
Lisp_Object Qtop_toolbar_shadow_pixmap;
Lisp_Object Qbottom_toolbar_shadow_pixmap;
Lisp_Object Qtoolbar_shadow_thickness;
Lisp_Object Qscrollbar_placement;
Lisp_Object Qinter_line_space;
Lisp_Object Qvisual_bell;
Lisp_Object Qbell_volume;
Lisp_Object Qpointer_background;
Lisp_Object Qpointer_color;
Lisp_Object Qtext_pointer;
Lisp_Object Qspace_pointer;
Lisp_Object Qmodeline_pointer;
Lisp_Object Qgc_pointer;
Lisp_Object Qinitially_unmapped;
Lisp_Object Quse_backing_store;
Lisp_Object Qborder_color;
Lisp_Object Qborder_width;

Lisp_Object Qframep, Qframe_live_p;
Lisp_Object Qdelete_frame;

Lisp_Object Qframe_title_format, Vframe_title_format;
Lisp_Object Qframe_icon_title_format, Vframe_icon_title_format;

Lisp_Object Vdefault_frame_name;
Lisp_Object Vdefault_frame_plist;

Lisp_Object Vframe_icon_glyph;

Lisp_Object Qhidden;

Lisp_Object Qvisible, Qiconic, Qinvisible, Qvisible_iconic, Qinvisible_iconic;
Lisp_Object Qnomini, Qvisible_nomini, Qiconic_nomini, Qinvisible_nomini;
Lisp_Object Qvisible_iconic_nomini, Qinvisible_iconic_nomini;

Lisp_Object Qset_specifier, Qset_face_property;
Lisp_Object Qface_property_instance;

Lisp_Object Qframe_property_alias;

/* If this is non-nil, it is the frame that make-frame is currently
   creating.  We can't set the current frame to this in case the
   debugger goes off because it would try and display to it.  However,
   there are some places which need to reference it which have no
   other way of getting it if it isn't the selected frame. */
Lisp_Object Vframe_being_created;
Lisp_Object Qframe_being_created;

static void store_minibuf_frame_prop(struct frame *f, Lisp_Object val);
static void frame_conversion_internal(struct frame *f, int pixel_to_char,
                                      int *pixel_width, int *pixel_height,
                                      int *char_width, int *char_height,
                                      int real_face);
static struct display_line title_string_display_line;
/* Used by generate_title_string. Global because they get used so much that
   the dynamic allocation time adds up. */
static Emchar_dynarr *title_string_emchar_dynarr;
\f
static Lisp_Object mark_frame(Lisp_Object obj)
{
        struct frame *f = XFRAME(obj);

#define MARKED_SLOT(x) mark_object (f->x)
#include "frameslots.h"

        if (FRAME_LIVE_P(f))    /* device is nil for a dead frame */
                MAYBE_FRAMEMETH(f, mark_frame, (f));

        return Qnil;
}

static void
print_frame(Lisp_Object obj, Lisp_Object printcharfun, int escapeflag)
{
        struct frame *frm = XFRAME(obj);

        if (print_readably)
                error("printing unreadable object #<frame %s 0x%x>",
                      XSTRING_DATA(frm->name), frm->header.uid);

        write_fmt_string(printcharfun, "#<%s-frame ", 
                         (!FRAME_LIVE_P(frm) ? "dead" : FRAME_TYPE_NAME(frm)));
        print_internal(frm->name, printcharfun, 1);
        write_fmt_str(printcharfun, " 0x%x>", frm->header.uid);
}

DEFINE_LRECORD_IMPLEMENTATION("frame", frame,
                              mark_frame, print_frame, 0, 0, 0, 0,
                              struct frame);
\f
static void nuke_all_frame_slots(struct frame *f)
{
#define MARKED_SLOT(x)  f->x = Qnil
#include "frameslots.h"
}

/* Allocate a new frame object and set all its fields to reasonable
   values.  The root window is created but the minibuffer will be done
   later. */

static struct frame *allocate_frame_core(Lisp_Object device)
{
        /* This function can GC */
        Lisp_Object frame;
        Lisp_Object root_window;
        struct frame *f = alloc_lcrecord_type(struct frame, &lrecord_frame);

        zero_lcrecord(f);
        nuke_all_frame_slots(f);
        XSETFRAME(frame, f);

        f->device = device;
        f->framemeths = XDEVICE(device)->devmeths;
        f->buffer_alist = Fcopy_sequence(Vbuffer_alist);

        root_window = allocate_window();
        XWINDOW(root_window)->frame = frame;

        /* 10 is arbitrary,
           Just so that there is "something there."
           Correct size will be set up later with change_frame_size.  */

        f->width = 10;
        f->height = 10;

        XWINDOW(root_window)->pixel_width = 10;
        XWINDOW(root_window)->pixel_height = 9;

        f->root_window = root_window;
        f->selected_window = root_window;
        f->last_nonminibuf_window = root_window;

        /* cache of subwindows visible on frame */
        f->subwindow_instance_cache = make_weak_list(WEAK_LIST_SIMPLE);

        /* associated exposure ignore list */
        f->subwindow_exposures = 0;
        f->subwindow_exposures_tail = 0;

        FRAME_SET_PAGENUMBER(f, 1);

        /* Choose a buffer for the frame's root window.  */
        XWINDOW(root_window)->buffer = Qt;
        {
                Lisp_Object buf = Fcurrent_buffer();
                Lisp_Object tmp = Fbuffer_name(buf);

                /* If buf is a 'hidden' buffer (i.e. one whose name starts with
                   a space), try to find another one.  */
                if (string_char(XSTRING(tmp), 0) == ' ') {
                        buf = Fother_buffer(buf, Qnil, Qnil);
                }
                Fset_window_buffer(root_window, buf, Qnil);
        }

        return f;
}

static void setup_normal_frame(struct frame *f)
{
        Lisp_Object mini_window;
        Lisp_Object frame;

        XSETFRAME(frame, f);

        mini_window = allocate_window();
        XWINDOW(f->root_window)->next = mini_window;
        XWINDOW(mini_window)->prev = f->root_window;
        XWINDOW(mini_window)->mini_p = Qt;
        XWINDOW(mini_window)->frame = frame;
        f->minibuffer_window = mini_window;
        f->has_minibuffer = 1;

        XWINDOW(mini_window)->buffer = Qt;
        Fset_window_buffer(mini_window, Vminibuffer_zero, Qt);
}

/* Make a frame using a separate minibuffer window on another frame.
   MINI_WINDOW is the minibuffer window to use.  nil means use the
   default-minibuffer-frame.  */

static void
setup_frame_without_minibuffer(struct frame *f, Lisp_Object mini_window)
{
        /* This function can GC */
        Lisp_Object device = f->device;

        if (!NILP(mini_window))
                CHECK_LIVE_WINDOW(mini_window);

        if (!NILP(mini_window)
            && !EQ(DEVICE_CONSOLE(XDEVICE(device)),
                   FRAME_CONSOLE(XFRAME(XWINDOW(mini_window)->frame))))
                error("frame and minibuffer must be on the same console");

        /* Do not create a default minibuffer frame on printer devices.  */
        if (NILP(mini_window)
            && DEVICE_DISPLAY_P(XDEVICE(FRAME_DEVICE(f)))) {
                struct console *con = XCONSOLE(FRAME_CONSOLE(f));
                /* Use default-minibuffer-frame if possible.  */
                if (!FRAMEP(con->default_minibuffer_frame)
                    || !FRAME_LIVE_P(XFRAME(con->default_minibuffer_frame))) {
                        /* If there's no minibuffer frame to use, create one.  */
                        con->default_minibuffer_frame
                            = call1(Qmake_initial_minibuffer_frame, device);
                }
                mini_window =
                    XFRAME(con->default_minibuffer_frame)->minibuffer_window;
        }

        /* Install the chosen minibuffer window, with proper buffer.  */
        if (!NILP(mini_window)) {
                store_minibuf_frame_prop(f, mini_window);
                Fset_window_buffer(mini_window, Vminibuffer_zero, Qt);
        } else
                f->minibuffer_window = Qnil;
}

/* Make a frame containing only a minibuffer window.  */

static void setup_minibuffer_frame(struct frame *f)
{
        /* This function can GC */
        /* First make a frame containing just a root window, no minibuffer.  */
        Lisp_Object mini_window;
        Lisp_Object frame;

        XSETFRAME(frame, f);

        f->no_split = 1;
        f->has_minibuffer = 1;

        /* Now label the root window as also being the minibuffer.
           Avoid infinite looping on the window chain by marking next pointer
           as nil. */

        mini_window = f->minibuffer_window = f->root_window;
        XWINDOW(mini_window)->mini_p = Qt;
        XWINDOW(mini_window)->next = Qnil;
        XWINDOW(mini_window)->prev = Qnil;
        XWINDOW(mini_window)->frame = frame;

        /* Put the proper buffer in that window.  */

        Fset_window_buffer(mini_window, Vminibuffer_zero, Qt);
}

static Lisp_Object make_sure_its_a_fresh_plist(Lisp_Object foolist)
{
        Lisp_Object tmp = Fcar(foolist);
        if (CONSP(tmp)) {
                /* looks like an alist to me. */
                foolist = Fcopy_alist(foolist);
                foolist = Fdestructive_alist_to_plist(foolist);
        } else {
                foolist = Fcopy_sequence(foolist);
        }
        return foolist;
}

DEFUN("make-frame", Fmake_frame, 0, 2, "",      /*
Create and return a new frame, displaying the current buffer.
Runs the functions listed in `create-frame-hook' after frame creation.

Optional argument PROPS is a property list (a list of alternating
keyword-value specifications) of properties for the new frame.
\(An alist is accepted for backward compatibility but should not
be passed in.)

See `set-frame-properties', `default-x-frame-plist', and
`default-tty-frame-plist' for the specially-recognized properties.
*/
      (props, device))
{
        struct frame *f;
        struct device *d;
        Lisp_Object frame = Qnil, name = Qnil, minibuf;
        struct gcpro gcpro1, gcpro2, gcpro3;
        int speccount = specpdl_depth();
        int first_frame_on_device = 0;
        int first_frame_on_console = 0;

        d = decode_device(device);
        XSETDEVICE(device, d);

        /* PROPS and NAME may be freshly-created, so make sure to GCPRO. */
        GCPRO3(frame, props, name);

        props = make_sure_its_a_fresh_plist(props);
        if (DEVICE_SPECIFIC_FRAME_PROPS(d))
                /* Put the device-specific props before the more general ones so
                   that they override them. */
                props = nconc2(props,
                               make_sure_its_a_fresh_plist
                               (*DEVICE_SPECIFIC_FRAME_PROPS(d)));
        props =
            nconc2(props, make_sure_its_a_fresh_plist(Vdefault_frame_plist));
        Fcanonicalize_lax_plist(props, Qnil);

        name = Flax_plist_get(props, Qname, Qnil);
        if (!NILP(name))
                CHECK_STRING(name);
        else if (STRINGP(Vdefault_frame_name))
                name = Vdefault_frame_name;
        else
                name = build_string("SXEmacs");

        if (!NILP(Fstring_match(make_string((const Bufbyte *)"\\.", 2), name,
                                Qnil, Qnil)))
                signal_simple_error(". not allowed in frame names", name);

        f = allocate_frame_core(device);
        XSETFRAME(frame, f);

        specbind(Qframe_being_created, name);
        f->name = name;

        FRAMEMETH(f, init_frame_1, (f, props));

        minibuf = Flax_plist_get(props, Qminibuffer, Qunbound);
        if (UNBOUNDP(minibuf)) {
                /* If minibuf is unspecified, then look for a minibuffer X resource. */
                /* #### Not implemented any more.  We need to fix things up so
                   that we search out all X resources and append them to the end of
                   props, above.  This is the only way in general to assure
                   coherent behavior for all frame properties/resources/etc. */
        } else
                props = Flax_plist_remprop(props, Qminibuffer);

        if (EQ(minibuf, Qnone) || NILP(minibuf))
                setup_frame_without_minibuffer(f, Qnil);
        else if (EQ(minibuf, Qonly))
                setup_minibuffer_frame(f);
        else if (WINDOWP(minibuf))
                setup_frame_without_minibuffer(f, minibuf);
        else if (EQ(minibuf, Qt) || UNBOUNDP(minibuf))
                setup_normal_frame(f);
        else
                signal_simple_error("Invalid value for `minibuffer'", minibuf);

        update_frame_window_mirror(f);

        if (initialized && !DEVICE_STREAM_P(d)) {
                if (!NILP(f->minibuffer_window))
                        reset_face_cachels(XWINDOW(f->minibuffer_window));
                reset_face_cachels(XWINDOW(f->root_window));
        }

        /* If no frames on this device formerly existed, say this is the
           first frame.  It kind of assumes that frameless devices don't
           exist, but it shouldn't be too harmful.  */
        if (NILP(DEVICE_FRAME_LIST(d)))
                first_frame_on_device = 1;

        /* This *must* go before the init_*() methods.  Those functions
           call Lisp code, and if any of them causes a warning to be displayed
           and the *Warnings* buffer to be created, it won't get added to
           the frame-specific version of the buffer-alist unless the frame
           is accessible from the device. */

#if 0
        DEVICE_FRAME_LIST(d) = nconc2(DEVICE_FRAME_LIST(d), Fcons(frame, Qnil));
#endif
        DEVICE_FRAME_LIST(d) = Fcons(frame, DEVICE_FRAME_LIST(d));
        RESET_CHANGED_SET_FLAGS;

        /* Now make sure that the initial cached values are set correctly.
           Do this after the init_frame method is called because that may
           do things (e.g. create widgets) that are necessary for the
           specifier value-changed methods to work OK. */
        recompute_all_cached_specifiers_in_frame(f);

        if (!DEVICE_STREAM_P(d)) {
                init_frame_faces(f);

#ifdef HAVE_SCROLLBARS
                /* Finish up resourcing the scrollbars. */
                init_frame_scrollbars(f);
#endif

#ifdef HAVE_TOOLBARS
                /* Create the initial toolbars.  We have to do this after the frame
                   methods are called because it may potentially call some things itself
                   which depend on the normal frame methods having initialized
                   things. */
                init_frame_toolbars(f);
#endif
                reset_face_cachels(XWINDOW(FRAME_SELECTED_WINDOW(f)));
                reset_glyph_cachels(XWINDOW(FRAME_SELECTED_WINDOW(f)));

                change_frame_size(f, f->height, f->width, 0);
        }

        MAYBE_FRAMEMETH(f, init_frame_2, (f, props));
        Fset_frame_properties(frame, props);
        MAYBE_FRAMEMETH(f, init_frame_3, (f));

        /* Hallelujah, praise the lord. */
        f->init_finished = 1;

        /* If this is the first frame on the device, make it the selected one. */
        if (first_frame_on_device && NILP(DEVICE_SELECTED_FRAME(d)))
                set_device_selected_frame(d, frame);

        /* If at startup or if the current console is a stream console
           (usually also at startup), make this console the selected one
           so that messages show up on it. */
        {
                Lisp_Object tmp = Fselected_console();
                if (NILP(tmp) || CONSOLE_STREAM_P(XCONSOLE(tmp))) {
                        Fselect_console(DEVICE_CONSOLE(d));
                }
        }

        first_frame_on_console =
            (first_frame_on_device &&
             XINT(Flength(CONSOLE_DEVICE_LIST(XCONSOLE(DEVICE_CONSOLE(d)))))
             == 1);

        /* #### all this calling of frame methods at various odd times
           is somewhat of a mess.  It's necessary to do it this way due
           to strange console-type-specific things that need to be done. */
        MAYBE_FRAMEMETH(f, after_init_frame, (f, first_frame_on_device,
                                              first_frame_on_console));

        if (!DEVICE_STREAM_P(d)) {
                /* Now initialise the gutters. This won't change the frame size,
                   but is needed as input to the layout that change_frame_size
                   will eventually do. Unfortunately gutter sizing code relies
                   on the frame in question being visible so we can't do this
                   earlier. */
                init_frame_gutters(f);

                change_frame_size(f, f->height, f->width, 0);
        }

        if (first_frame_on_device) {
                if (first_frame_on_console)
                        va_run_hook_with_args(Qcreate_console_hook, 1,
                                              DEVICE_CONSOLE(d));
                va_run_hook_with_args(Qcreate_device_hook, 1, device);
        }
        va_run_hook_with_args(Qcreate_frame_hook, 1, frame);

        /* Initialize custom-specific stuff. */
        if (!UNBOUNDP(symbol_function(XSYMBOL(Qcustom_initialize_frame))))
                call1(Qcustom_initialize_frame, frame);

        unbind_to(speccount, Qnil);

        UNGCPRO;
        return frame;
}
\f
/* this function should be used in most cases when a Lisp function is passed
   a FRAME argument.  Use this unless you don't accept nil == current frame
   (in which case, do a CHECK_LIVE_FRAME() and then an XFRAME()) or you
   allow dead frames.  Note that very few functions should accept dead
   frames.  It could be argued that functions should just do nothing when
   given a dead frame, but the presence of a dead frame usually indicates
   an oversight in the Lisp code that could potentially lead to strange
   results and so it is better to catch the error early.

   If you only accept X frames, use decode_x_frame(), which does what this
   function does but also makes sure the frame is an X frame. */

struct frame *decode_frame(Lisp_Object frame)
{
        if (NILP(frame))
                return selected_frame();

        CHECK_LIVE_FRAME(frame);
        return XFRAME(frame);
}

struct frame *decode_frame_or_selected(Lisp_Object cdf)
{
        if (CONSOLEP(cdf))
                cdf = CONSOLE_SELECTED_DEVICE(decode_console(cdf));
        if (DEVICEP(cdf))
                cdf = DEVICE_SELECTED_FRAME(decode_device(cdf));
        return decode_frame(cdf);
}

Lisp_Object make_frame(struct frame * f)
{
        Lisp_Object frame;
        XSETFRAME(frame, f);
        return frame;
}
\f
/*
 * window size changes are held up during critical regions.  Afterwards,
 * we want to deal with any delayed changes.
 */
void hold_frame_size_changes(void)
{
        in_display = 1;
}

void unhold_one_frame_size_changes(struct frame *f)
{
        in_display = 0;

        if (f->size_change_pending)
                change_frame_size(f, f->new_height, f->new_width, 0);
}

void unhold_frame_size_changes(void)
{
        Lisp_Object frmcons, devcons, concons;

        FRAME_LOOP_NO_BREAK(frmcons, devcons, concons)
            unhold_one_frame_size_changes(XFRAME(XCAR(frmcons)));
}

void invalidate_vertical_divider_cache_in_frame(struct frame *f)
{
        /* Invalidate cached value of needs_vertical_divider_p in
           every and all windows */
        map_windows(f, invalidate_vertical_divider_cache_in_window, 0);
}
\f
/*
 * Frame size may change due to changes in scrollbars, toolbars,
 * default font etc. These changes are applied early in redisplay
 * frame.
 */
void adjust_frame_size(struct frame *f)
{
        int keep_char_size = 0;
        Lisp_Object frame;
        XSETFRAME(frame, f);

        if (!f->size_slipped)
                return;

        /* Don't adjust tty frames. #### May break when TTY have menubars.
           Then, write an Vadjust_frame_function which will return t for TTY
           frames. Another solution is frame_size_fixed_p method for TTYs,
           which always returned yes it's fixed.
         */
        if (!FRAME_WIN_P(f)) {
                CLEAR_FRAME_SIZE_SLIPPED(f);
                return;
        }

        /* frame_size_fixed_p tells that frame size cannot currently
           be changed change due to external conditions */
        if (!FRAMEMETH_OR_GIVEN(f, frame_size_fixed_p, (f), 0)) {
                if (NILP(Vadjust_frame_function))
                        keep_char_size = 1;
                else if (EQ(Vadjust_frame_function, Qt))
                        keep_char_size = 0;
                else
                        keep_char_size =
                            NILP(call1_trapping_errors
                                 ("Error in adjust-frame-function",
                                  Vadjust_frame_function, frame));

                if (keep_char_size)
                        Fset_frame_size(frame, make_int(FRAME_CHARWIDTH(f)),
                                        make_int(FRAME_CHARHEIGHT(f)), Qnil);
        }

        if (!keep_char_size) {
                int height, width;
                pixel_to_char_size(f, FRAME_PIXWIDTH(f), FRAME_PIXHEIGHT(f),
                                   &width, &height);
                change_frame_size(f, height, width, 0);
                CLEAR_FRAME_SIZE_SLIPPED(f);
        }
}

/*
 * This is a "specifier changed in frame" handler for various specifiers
 * changing which causes frame size adjustment
 */
void
frame_size_slipped(Lisp_Object specifier, struct frame *f, Lisp_Object oldval)
{
        MARK_FRAME_SIZE_SLIPPED(f);
}
\f
DEFUN("framep", Fframep, 1, 1, 0,       /*
Return non-nil if OBJECT is a frame.
Also see `frame-live-p'.
Note that FSF Emacs kludgily returns a value indicating what type of
frame this is.  Use the cleaner function `frame-type' for that.
*/
      (object))
{
        return FRAMEP(object) ? Qt : Qnil;
}

DEFUN("frame-live-p", Fframe_live_p, 1, 1, 0,   /*
Return non-nil if OBJECT is a frame which has not been deleted.
*/
      (object))
{
        return FRAMEP(object) && FRAME_LIVE_P(XFRAME(object)) ? Qt : Qnil;
}
\f
DEFUN("focus-frame", Ffocus_frame, 1, 1, 0,     /*
Select FRAME and give it the window system focus.
This function is not affected by the value of `focus-follows-mouse'.
*/
      (frame))
{
        CHECK_LIVE_FRAME(frame);

        MAYBE_DEVMETH(XDEVICE(FRAME_DEVICE(XFRAME(frame))), focus_on_frame,
                      (XFRAME(frame)));
        /* FRAME will be selected by the time we receive the next event.
           However, it is better to select it explicitly now, in case the
           Lisp code depends on frame being selected.  */
        Fselect_frame(frame);
        return Qnil;
}

/* Called from Fselect_window() */
void select_frame_1(Lisp_Object frame)
{
        struct frame *f = XFRAME(frame);
        Lisp_Object old_selected_frame = Fselected_frame(Qnil);

        if (EQ(frame, old_selected_frame))
                return;

        /* now select the frame's device */
        set_device_selected_frame(XDEVICE(FRAME_DEVICE(f)), frame);
        select_device_1(FRAME_DEVICE(f));

        update_frame_window_mirror(f);
}

DEFUN("select-frame", Fselect_frame, 1, 1, 0,   /*
Select the frame FRAME.
Subsequent editing commands apply to its selected window.
The selection of FRAME lasts until the next time the user does
something to select a different frame, or until the next time this
function is called.

Note that this does not actually cause the window-system focus to be
set to this frame, or the `select-frame-hook' or `deselect-frame-hook'
to be run, until the next time that SXEmacs is waiting for an event.

Also note that when focus-follows-mouse is non-nil, the frame
selection is temporary and is reverted when the current command
terminates, much like the buffer selected by `set-buffer'.  In order
to effect a permanent focus change, use `focus-frame'.
*/
      (frame))
{
        CHECK_LIVE_FRAME(frame);

        /* select the frame's selected window.  This will call
           selected_frame_1(). */
        Fselect_window(FRAME_SELECTED_WINDOW(XFRAME(frame)), Qnil);

        /* Nothing should be depending on the return value of this function.
           But, of course, there is stuff out there which is. */
        return frame;
}

/* use this to retrieve the currently selected frame.  You should use
   this in preference to Fselected_frame (Qnil) unless you are prepared
   to handle the possibility of there being no selected frame (this
   happens at some points during startup). */

struct frame *selected_frame(void)
{
        Lisp_Object device = Fselected_device(Qnil);
        Lisp_Object frame = DEVICE_SELECTED_FRAME(XDEVICE(device));
        if (NILP(frame))
                signal_simple_error("No frames exist on device", device);
        return XFRAME(frame);
}

/* use this instead of XFRAME (DEVICE_SELECTED_FRAME (d)) to catch
   the possibility of there being no frames on the device (just created).
   There is no point doing this inside of redisplay because errors
   cause an abort(), indicating a flaw in the logic, and error_check_frame()
   will catch this just as well. */

struct frame *device_selected_frame(struct device *d)
{
        Lisp_Object frame = DEVICE_SELECTED_FRAME(d);
        if (NILP(frame)) {
                Lisp_Object device;
                XSETDEVICE(device, d);
                signal_simple_error("No frames exist on device", device);
        }
        return XFRAME(frame);
}

#if 0                           /* FSFmacs */

xxDEFUN("handle-switch-frame", Fhandle_switch_frame, 1, 2, "e", /*
Handle a switch-frame event EVENT.
Switch-frame events are usually bound to this function.
A switch-frame event tells Emacs that the window manager has requested
that the user's events be directed to the frame mentioned in the event.
This function selects the selected window of the frame of EVENT.

If EVENT is frame object, handle it as if it were a switch-frame event
to that frame.
                                                                 */
        (frame, no_enter))
{
        /* Preserve prefix arg that the command loop just cleared.  */
        XCONSOLE(Vselected_console)->prefix_arg = Vcurrent_prefix_arg;
#if 0                           /* unclean! */
        run_hook(Qmouse_leave_buffer_hook);
#endif
        return do_switch_frame(frame, no_enter, 0);
}

/* A load of garbage. */
xxDEFUN("ignore-event", Fignore_event, 0, 0, "",        /*
Do nothing, but preserve any prefix argument already specified.
This is a suitable binding for iconify-frame and make-frame-visible.
                                                         */
        ())
{
        struct console *c = XCONSOLE(Vselected_console);

        c->prefix_arg = Vcurrent_prefix_arg;
        return Qnil;
}

#endif                          /* 0 */

DEFUN("selected-frame", Fselected_frame, 0, 1, 0,       /*
Return the frame that is now selected on device DEVICE.
If DEVICE is not specified, the selected device will be used.
If no frames exist on the device, nil is returned.
*/
      (device))
{
        if (NILP(device) && NILP(Fselected_device(Qnil)))
                return Qnil;    /* happens early in temacs */
        return DEVICE_SELECTED_FRAME(decode_device(device));
}

Lisp_Object frame_first_window(struct frame * f)
{
        Lisp_Object w = f->root_window;

        while (1) {
                if (!NILP(XWINDOW(w)->hchild))
                        w = XWINDOW(w)->hchild;
                else if (!NILP(XWINDOW(w)->vchild))
                        w = XWINDOW(w)->vchild;
                else
                        break;
        }

        return w;
}

DEFUN("active-minibuffer-window", Factive_minibuffer_window, 0, 0, 0,   /*
Return the currently active minibuffer window, or nil if none.
*/
      ())
{
        return minibuf_level ? minibuf_window : Qnil;
}

DEFUN("last-nonminibuf-frame", Flast_nonminibuf_frame, 0, 1, 0, /*
Return the most-recently-selected non-minibuffer-only frame on CONSOLE.
This will always be the same as (selected-frame device) unless the
selected frame is a minibuffer-only frame.
CONSOLE defaults to the selected console if omitted.
*/
      (console))
{
        Lisp_Object result;

        XSETCONSOLE(console, decode_console(console));
        /* Just in case the machinations in delete_frame_internal() resulted
           in the last-nonminibuf-frame getting out of sync, make sure and
           return the selected frame if it's acceptable. */
        result = Fselected_frame(CONSOLE_SELECTED_DEVICE(XCONSOLE(console)));
        if (!NILP(result) && !FRAME_MINIBUF_ONLY_P(XFRAME(result)))
                return result;
        return CONSOLE_LAST_NONMINIBUF_FRAME(XCONSOLE(console));
}

DEFUN("frame-root-window", Fframe_root_window, 0, 1, 0, /*
Return the root-window of FRAME.
If omitted, FRAME defaults to the currently selected frame.
*/
      (frame))
{
        struct frame *f = decode_frame(frame);
        return FRAME_ROOT_WINDOW(f);
}

DEFUN("frame-selected-window", Fframe_selected_window, 0, 1, 0, /*
Return the selected window of frame object FRAME.
If omitted, FRAME defaults to the currently selected frame.
*/
      (frame))
{
        struct frame *f = decode_frame(frame);
        return FRAME_SELECTED_WINDOW(f);
}

void set_frame_selected_window(struct frame *f, Lisp_Object window)
{
        assert(XFRAME(WINDOW_FRAME(XWINDOW(window))) == f);
        f->selected_window = window;
        if (!MINI_WINDOW_P(XWINDOW(window)) || FRAME_MINIBUF_ONLY_P(f)) {
                if (!EQ(f->last_nonminibuf_window, window)) {
#ifdef HAVE_TOOLBARS
                        MARK_TOOLBAR_CHANGED;
#endif
                        MARK_GUTTER_CHANGED;
                }
                f->last_nonminibuf_window = window;
        }
}

DEFUN("set-frame-selected-window", Fset_frame_selected_window, 2, 2, 0, /*
Set the selected window of FRAME to WINDOW.
If FRAME is nil, the selected frame is used.
If FRAME is the selected frame, this makes WINDOW the selected window.
*/
      (frame, window))
{
        XSETFRAME(frame, decode_frame(frame));
        CHECK_LIVE_WINDOW(window);

        if (!EQ(frame, WINDOW_FRAME(XWINDOW(window))))
                error("In `set-frame-selected-window', WINDOW is not on FRAME");

        if (XFRAME(frame) == selected_frame())
                return Fselect_window(window, Qnil);

        set_frame_selected_window(XFRAME(frame), window);
        return window;
}
\f
DEFUN("frame-device", Fframe_device, 0, 1, 0,   /*
Return the device that FRAME is on.
If omitted, FRAME defaults to the currently selected frame.
*/
      (frame))
{
        return FRAME_DEVICE(decode_frame(frame));
}

int is_surrogate_for_selected_frame(struct frame *f)
{
        struct device *d = XDEVICE(f->device);
        struct frame *dsf = device_selected_frame(d);

        /* Can't be a surrogate for ourselves. */
        if (f == dsf)
                return 0;

        if (!FRAME_HAS_MINIBUF_P(dsf) &&
            f == XFRAME(WINDOW_FRAME(XWINDOW(FRAME_MINIBUF_WINDOW(dsf)))))
                return 1;
        else
                return 0;
}

static int frame_matches_frame_spec(Lisp_Object frame, Lisp_Object type)
{
        struct frame *f = XFRAME(frame);

        if (WINDOWP(type)) {
                CHECK_LIVE_WINDOW(type);

                if (EQ(FRAME_MINIBUF_WINDOW(f), type)
                    /* Check that F either is, or has forwarded
                       its focus to, TYPE's frame.  */
                    && (EQ(WINDOW_FRAME(XWINDOW(type)), frame)
                        || EQ(WINDOW_FRAME(XWINDOW(type)),
                              FRAME_FOCUS_FRAME(f))))
                        return 1;
                else
                        return 0;
        }
#if 0                           /* FSFmacs */
        if (EQ(type, Qvisible) || EQ(type, Qiconic) || EQ(type, Qvisible_iconic)
            || EQ(type, Qvisible_nomini) || EQ(type, Qiconic_nomini)
            || EQ(type, Qvisible_iconic_nomini))
                FRAME_SAMPLE_VISIBILITY(f);
#endif

        if (NILP(type))
                type = Qnomini;
        if (ZEROP(type))
                type = Qvisible_iconic;

        if (EQ(type, Qvisible))
                return FRAME_VISIBLE_P(f);
        if (EQ(type, Qiconic))
                return FRAME_ICONIFIED_P(f);
        if (EQ(type, Qinvisible))
                return !FRAME_VISIBLE_P(f) && !FRAME_ICONIFIED_P(f);
        if (EQ(type, Qvisible_iconic))
                return FRAME_VISIBLE_P(f) || FRAME_ICONIFIED_P(f);
        if (EQ(type, Qinvisible_iconic))
                return !FRAME_VISIBLE_P(f);

        if (EQ(type, Qnomini))
                return !FRAME_MINIBUF_ONLY_P(f);
        if (EQ(type, Qvisible_nomini))
                return FRAME_VISIBLE_P(f) && !FRAME_MINIBUF_ONLY_P(f);
        if (EQ(type, Qiconic_nomini))
                return FRAME_ICONIFIED_P(f) && !FRAME_MINIBUF_ONLY_P(f);
        if (EQ(type, Qinvisible_nomini))
                return !FRAME_VISIBLE_P(f) && !FRAME_ICONIFIED_P(f) &&
                    !FRAME_MINIBUF_ONLY_P(f);
        if (EQ(type, Qvisible_iconic_nomini))
                return ((FRAME_VISIBLE_P(f) || FRAME_ICONIFIED_P(f))
                        && !FRAME_MINIBUF_ONLY_P(f));
        if (EQ(type, Qinvisible_iconic_nomini))
                return !FRAME_VISIBLE_P(f) && !FRAME_MINIBUF_ONLY_P(f);

        return 1;
}

int device_matches_device_spec(Lisp_Object device, Lisp_Object device_spec)
{
        if (EQ(device_spec, Qwindow_system))
                return DEVICE_WIN_P(XDEVICE(device));
        if (DEVICEP(device_spec))
                return EQ(device, device_spec);
        if (CONSOLEP(device_spec))
                return EQ(DEVICE_CONSOLE(XDEVICE(device)), device_spec);
        if (valid_console_type_p(device_spec))
                return EQ(DEVICE_TYPE(XDEVICE(device)), device_spec);
        return 1;
}

/* Return the next frame in the frame list after FRAME.
   WHICH-FRAMES and WHICH-DEVICES control which frames and devices
   are considered; see `next-frame'. */

Lisp_Object
next_frame(Lisp_Object frame, Lisp_Object which_frames,
           Lisp_Object which_devices)
{
        Lisp_Object first = Qnil;
        Lisp_Object devcons, concons;
        int passed = 0;

        CHECK_LIVE_FRAME(frame);

        DEVICE_LOOP_NO_BREAK(devcons, concons) {
                Lisp_Object device = XCAR(devcons);
                Lisp_Object frmcons;

                if (!device_matches_device_spec(device, which_devices)) {
                        if (EQ(device, FRAME_DEVICE(XFRAME(frame))))
                                passed = 1;
                        continue;
                }

                DEVICE_FRAME_LOOP(frmcons, XDEVICE(device)) {
                        Lisp_Object f = XCAR(frmcons);

                        if (passed) {
                                if (frame_matches_frame_spec(f, which_frames))
                                        return f;
                        } else {
                                if (EQ(frame, f)) {
                                        passed = 1;
                                } else {
                                        if (NILP(first)
                                            && frame_matches_frame_spec(f,
                                                                        which_frames))
                                                first = f;
                                }
                        }
                }
        }

        if (NILP(first))
                /* We went through the whole frame list without finding a single
                   acceptable frame.  Return the original frame.  */
                return frame;
        else
                /* There were no acceptable frames in the list after FRAME; otherwise,
                   we would have returned directly from the loop.  Since FIRST is the last
                   acceptable frame in the list, return it.  */
                return first;
}

/* Return the previous frame in the frame list before FRAME.
   WHICH-FRAMES and WHICH-DEVICES control which frames and devices
   are considered; see `next-frame'. */

Lisp_Object
previous_frame(Lisp_Object frame, Lisp_Object which_frames,
               Lisp_Object which_devices)
{
        Lisp_Object devcons, concons;
        Lisp_Object last = Qnil;

        CHECK_LIVE_FRAME(frame);

        DEVICE_LOOP_NO_BREAK(devcons, concons) {
                Lisp_Object device = XCAR(devcons);
                Lisp_Object frmcons;

                if (!device_matches_device_spec(device, which_devices)) {
                        if (EQ(device, FRAME_DEVICE(XFRAME(frame)))
                            && !NILP(last))
                                return last;
                        continue;
                }

                DEVICE_FRAME_LOOP(frmcons, XDEVICE(device)) {
                        Lisp_Object f = XCAR(frmcons);

                        if (EQ(frame, f)) {
                                if (!NILP(last))
                                        return last;
                        } else {
                                if (frame_matches_frame_spec(f, which_frames))
                                        last = f;
                        }
                }
        }

        if (NILP(last))
                /* We went through the whole frame list without finding a single
                   acceptable frame.  Return the original frame.  */
                return frame;
        else
                /* There were no acceptable frames in the list before FRAME; otherwise,
                   we would have returned directly from the loop.  Since LAST is the last
                   acceptable frame in the list, return it.  */
                return last;
}

DEFUN("next-frame", Fnext_frame, 0, 3, 0,       /*
Return the next frame of the right type in the frame list after FRAME.
WHICH-FRAMES controls which frames are eligible to be returned; all
others will be skipped.  Note that if there is only one eligible
frame, then `next-frame' called repeatedly will always return
the same frame, and if there is no eligible frame, then FRAME is
returned.

Possible values for WHICH-FRAMES are

'visible           Consider only frames that are visible.
'iconic                    Consider only frames that are iconic.
'invisible                 Consider only frames that are invisible
(this is different from iconic).
'visible-iconic            Consider frames that are visible or iconic.
'invisible-iconic  Consider frames that are invisible or iconic.
'nomini                    Consider all frames except minibuffer-only ones.
'visible-nomini            Like `visible' but omits minibuffer-only frames.
'iconic-nomini             Like `iconic' but omits minibuffer-only frames.
'invisible-nomini  Like `invisible' but omits minibuffer-only frames.
'visible-iconic-nomini     Like `visible-iconic' but omits minibuffer-only
frames.
'invisible-iconic-nomini Like `invisible-iconic' but omits minibuffer-only
frames.
any other value            Consider all frames.

If WHICH-FRAMES is omitted, 'nomini is used.  A value for WHICH-FRAMES
of 0 (a number) is treated like 'iconic, for backwards compatibility.

If WHICH-FRAMES is a window, include only its own frame and any frame
now using that window as the minibuffer.

The optional third argument WHICH-DEVICES further clarifies on which
devices to search for frames as specified by WHICH-FRAMES.
If nil or omitted, search all devices on FRAME's console.
If a device, only search that device.
If a console, search all devices on that console.
If a device type, search all devices of that type.
If `window-system', search all window-system devices.
Any other non-nil value means search all devices.
*/
      (frame, which_frames, which_devices))
{
        XSETFRAME(frame, decode_frame(frame));

        return next_frame(frame, which_frames, which_devices);
}

DEFUN("previous-frame", Fprevious_frame, 0, 3, 0,       /*
Return the next frame of the right type in the frame list after FRAME.
WHICH-FRAMES controls which frames are eligible to be returned; all
others will be skipped.  Note that if there is only one eligible
frame, then `previous-frame' called repeatedly will always return
the same frame, and if there is no eligible frame, then FRAME is
returned.

See `next-frame' for an explanation of the WHICH-FRAMES and WHICH-DEVICES
arguments.
*/
      (frame, which_frames, which_devices))
{
        XSETFRAME(frame, decode_frame(frame));

        return previous_frame(frame, which_frames, which_devices);
}

/* Return any frame for which PREDICATE is non-zero, or return Qnil
   if there aren't any. */

Lisp_Object
find_some_frame(int (*predicate) (Lisp_Object, void *), void *closure)
{
        Lisp_Object framecons, devcons, concons;

        FRAME_LOOP_NO_BREAK(framecons, devcons, concons) {
                Lisp_Object frame = XCAR(framecons);

                if ((predicate) (frame, closure))
                        return frame;
        }

        return Qnil;
}
\f
/* extern void free_line_insertion_deletion_costs (struct frame *f); */

/* Return 1 if it is ok to delete frame F;
   0 if all frames aside from F are invisible.
   (Exception: if F is a stream frame, it's OK to delete if
   any other frames exist.) */

int other_visible_frames(struct frame *f)
{
        Lisp_Object frame;

        XSETFRAME(frame, f);
        if (FRAME_STREAM_P(f))
                return !EQ(frame, next_frame(frame, Qt, Qt));
        return !EQ(frame, next_frame(frame, Qvisible_iconic_nomini, Qt));
}

/* Delete frame F.

   If FORCE is non-zero, allow deletion of the only frame.

   If CALLED_FROM_DELETE_DEVICE is non-zero, then, if
   deleting the last frame on a device, just delete it,
   instead of calling `delete-device'.

   If FROM_IO_ERROR is non-zero, then the frame is gone due
   to an I/O error.  This affects what happens if we exit
   (we do an emergency exit instead of `save-buffers-kill-emacs'.)
*/

void
delete_frame_internal(struct frame *f, int force,
                      int called_from_delete_device, int from_io_error)
{
        /* This function can GC */
        int minibuffer_selected;
        struct device *d;
        struct console *con;
        Lisp_Object frame;
        Lisp_Object device;
        Lisp_Object console;
        struct gcpro gcpro1;

        /* OK to delete an already deleted frame. */
        if (!FRAME_LIVE_P(f))
                return;

        XSETFRAME(frame, f);
        GCPRO1(frame);

        device = FRAME_DEVICE(f);
        d = XDEVICE(device);
        console = DEVICE_CONSOLE(d);
        con = XCONSOLE(console);

        if (!called_from_delete_device
            && !DEVICE_IMPL_FLAG(d, XDEVIMPF_FRAMELESS_OK)) {
                /* If we're deleting the only non-minibuffer frame on the
                   device, delete the device. */
                if (EQ(frame, next_frame(frame, Qnomini, FRAME_DEVICE(f)))) {
                        delete_device_internal(d, force, 0, from_io_error);
                        UNGCPRO;
                        return;
                }
        }

        /* In FSF, delete-frame will not normally allow you to delete the
           last visible frame.  This was too annoying, so we changed it to the
           only frame.  However, this would let people shoot themselves by
           deleting all frames which were either visible or iconified and thus
           losing any way of communicating with the still running SXEmacs process.
           So we put it back.  */
        if (!force && !allow_deletion_of_last_visible_frame &&
            !other_visible_frames(f))
                error("Attempt to delete the sole visible or iconified frame");

        /* Does this frame have a minibuffer, and is it the surrogate
           minibuffer for any other frame?  */
        if (FRAME_HAS_MINIBUF_P(f)) {
                Lisp_Object frmcons, devcons, concons;

                FRAME_LOOP_NO_BREAK(frmcons, devcons, concons) {
                        Lisp_Object this = XCAR(frmcons);

                        if (!EQ(this, frame)
                            && EQ(frame, (WINDOW_FRAME
                                          (XWINDOW
                                           (FRAME_MINIBUF_WINDOW
                                            (XFRAME(this))))))) {
                                /* We've found another frame whose minibuffer is on
                                   this frame. */
                                signal_simple_error
                                    ("Attempt to delete a surrogate minibuffer frame",
                                     frame);
                        }
                }
        }

        /* Test for popup frames hanging around. */
        /* Deletion of a parent frame with popups is deadly. */
        {
                Lisp_Object frmcons, devcons, concons;

                FRAME_LOOP_NO_BREAK(frmcons, devcons, concons) {
                        Lisp_Object this = XCAR(frmcons);

                        if (!EQ(this, frame)) {
                                struct device *devcons_d =
                                    XDEVICE(XCAR(devcons));
                                if (EQ
                                    (frame,
                                     DEVMETH_OR_GIVEN(devcons_d,
                                                      get_frame_parent,
                                                      (XFRAME(this)), Qnil)))
                                        /* We've found a popup frame whose parent is this frame. */
                                        signal_simple_error
                                            ("Attempt to delete a frame with live popups",
                                             frame);
                        }
                }
        }

        /* Before here, we haven't made any dangerous changes (just checked for
           error conditions).  Now run the delete-frame-hook.  Remember that
           user code there could do any number of dangerous things, including
           signalling an error. */

        va_run_hook_with_args(Qdelete_frame_hook, 1, frame);

        if (!FRAME_LIVE_P(f)) { /* Make sure the delete-frame-hook didn't *//* go ahead and delete anything. */
                UNGCPRO;
                return;
        }

        /* Call the delete-device-hook and delete-console-hook now if
           appropriate, before we do any dangerous things -- they too could
           signal an error. */
        if (XINT(Flength(DEVICE_FRAME_LIST(d))) == 1) {
                va_run_hook_with_args(Qdelete_device_hook, 1, device);
                if (!FRAME_LIVE_P(f)) { /* Make sure the delete-device-hook didn't *//* go ahead and delete anything. */
                        UNGCPRO;
                        return;
                }

                if (XINT(Flength(CONSOLE_DEVICE_LIST(con))) == 1) {
                        va_run_hook_with_args(Qdelete_console_hook, 1, console);
                        if (!FRAME_LIVE_P(f)) { /* Make sure the delete-console-hook didn't *//* go ahead and delete anything. */
                                UNGCPRO;
                                return;
                        }
                }
        }

        minibuffer_selected = EQ(minibuf_window, Fselected_window(Qnil));

        /* If we were focused on this frame, then we're not any more.
           Assume that we lost the focus; that way, the call to
           Fselect_frame() below won't end up making us explicitly
           focus on another frame, which is generally undesirable in
           a point-to-type world.  If our mouse ends up sitting over
           another frame, we will receive a FocusIn event and end up
           making that frame the selected frame.

           #### This may not be an ideal solution in a click-to-type
           world (in that case, we might want to explicitly choose
           another frame to have the focus, rather than relying on
           the WM, which might focus on a frame in a different app
           or focus on nothing at all).  But there's no easy way
           to detect which focus model we're running on, and the
           alternative is more heinous. */

        if (EQ(frame, DEVICE_FRAME_WITH_FOCUS_REAL(d)))
                DEVICE_FRAME_WITH_FOCUS_REAL(d) = Qnil;
        if (EQ(frame, DEVICE_FRAME_WITH_FOCUS_FOR_HOOKS(d)))
                DEVICE_FRAME_WITH_FOCUS_FOR_HOOKS(d) = Qnil;
        if (EQ(frame, DEVICE_FRAME_THAT_OUGHT_TO_HAVE_FOCUS(d)))
                DEVICE_FRAME_THAT_OUGHT_TO_HAVE_FOCUS(d) = Qnil;

        /* Don't allow the deleted frame to remain selected.
           Note that in the former scheme of things, this would
           have caused us to regain the focus.  This no longer
           applies (see above); I think the new behavior is more
           logical.  If someone disagrees, it can always be
           changed (or a new user variable can be introduced, ugh.) */
        if (EQ(frame, DEVICE_SELECTED_FRAME(d))) {
                Lisp_Object next;

                /* If this is a popup frame, select its parent if possible.
                   Otherwise, find another visible frame; if none, just take any frame.
                   First try the same device, then the same console. */

                next = DEVMETH_OR_GIVEN(d, get_frame_parent, (f), Qnil);
                if (NILP(next) || EQ(next, frame)
                    || !FRAME_LIVE_P(XFRAME(next)))
                        next = next_frame(frame, Qvisible, device);
                if (NILP(next) || EQ(next, frame))
                        next = next_frame(frame, Qvisible, console);
                if (NILP(next) || EQ(next, frame))
                        next = next_frame(frame, Qvisible, Qt);
                if (NILP(next) || EQ(next, frame))
                        next = next_frame(frame, Qt, device);
                if (NILP(next) || EQ(next, frame))
                        next = next_frame(frame, Qt, console);
                if (NILP(next) || EQ(next, frame))
                        next = next_frame(frame, Qt, Qt);

                /* if we haven't found another frame at this point
                   then there aren't any. */
                if (NILP(next) || EQ(next, frame)) ;
                else {
                        int did_select = 0;
                        /* if this is the global selected frame, select another one. */
                        if (EQ(frame, Fselected_frame(Qnil))) {
                                Fselect_frame(next);
                                did_select = 1;
                        }
                        /*
                         * If the new frame we just selected is on a different
                         * device then we still need to change DEVICE_SELECTED_FRAME(d)
                         * to a live frame, if there are any left on this device.
                         */
                        if (!EQ(device, FRAME_DEVICE(XFRAME(next)))) {
                                Lisp_Object next_f =
                                    next_frame(frame, Qt, device);
                                if (NILP(next_f) || EQ(next_f, frame))
                                        set_device_selected_frame(d, Qnil);
                                else
                                        set_device_selected_frame(d, next_f);
                        } else if (!did_select)
                                set_device_selected_frame(d, next);

                }
        }

        /* Don't allow minibuf_window to remain on a deleted frame.  */
        if (EQ(f->minibuffer_window, minibuf_window)) {
                struct frame *sel_frame = selected_frame();
                Fset_window_buffer(sel_frame->minibuffer_window,
                                   XWINDOW(minibuf_window)->buffer, Qt);
                minibuf_window = sel_frame->minibuffer_window;

                /* If the dying minibuffer window was selected,
                   select the new one.  */
                if (minibuffer_selected)
                        Fselect_window(minibuf_window, Qnil);
        }

        /* After this point, no errors must be allowed to occur. */

#ifdef HAVE_MENUBARS
        free_frame_menubars(f);
#endif
#ifdef HAVE_SCROLLBARS
        free_frame_scrollbars(f);
#endif
#ifdef HAVE_TOOLBARS
        free_frame_toolbars(f);
#endif
        free_frame_gutters(f);
        /* Unfortunately deleting the frame will also delete the parent of
           all of the subwindow instances current on the frame. I think this
           can lead to bad things when trying to finalize the
           instances. Thus we loop over all instance caches calling the
           finalize method for each instance. */
        free_frame_subwindow_instances(f);

        /* This must be done before the window and window_mirror structures
           are freed.  The scrollbar information is attached to them. */
        MAYBE_FRAMEMETH(f, delete_frame, (f));

        /* Mark all the windows that used to be on FRAME as deleted, and then
           remove the reference to them.  */
        delete_all_subwindows(XWINDOW(f->root_window));
        f->root_window = Qnil;

        /* clear out the cached glyph information */
        f->subwindow_instance_cache = Qnil;

        /* Remove the frame now from the list.  This way, any events generated
           on this frame by the maneuvers below will disperse themselves. */

        /* This used to be Fdelq(), but that will cause a seg fault if the
           QUIT checker happens to get invoked, because the frame list is in
           an inconsistent state. */
        d->frame_list = delq_no_quit(frame, d->frame_list);
        RESET_CHANGED_SET_FLAGS;

        f->dead = 1;
        f->visible = 0;

        free_window_mirror(f->root_mirror);
/*  free_line_insertion_deletion_costs (f); */

        /* If we've deleted the last non-minibuf frame, then try to find
           another one.  */
        if (EQ(frame, CONSOLE_LAST_NONMINIBUF_FRAME(con))) {
                Lisp_Object frmcons, devcons;

                set_console_last_nonminibuf_frame(con, Qnil);

                CONSOLE_FRAME_LOOP_NO_BREAK(frmcons, devcons, con) {
                        Lisp_Object ecran = XCAR(frmcons);
                        if (!FRAME_MINIBUF_ONLY_P(XFRAME(ecran))) {
                                set_console_last_nonminibuf_frame(con, ecran);
                                goto double_break_1;
                        }
                }
        }
      double_break_1:

#if 0
        /* The following test is degenerate FALSE */
        if (called_from_delete_device < 0)
                /* then we're being called from delete-console, and we shouldn't
                   try to find another default-minibuffer frame for the console.
                 */
                con->default_minibuffer_frame = Qnil;
#endif

        /* If we've deleted this console's default_minibuffer_frame, try to
           find another one.  Prefer minibuffer-only frames, but also notice
           frames with other windows.  */
        if (EQ(frame, con->default_minibuffer_frame)) {
                Lisp_Object frmcons, devcons;
                /* The last frame we saw with a minibuffer, minibuffer-only or not.  */
                Lisp_Object frame_with_minibuf;
                /* Some frame we found on the same console, or nil if there are none. */
                Lisp_Object frame_on_same_console;

                frame_on_same_console = Qnil;
                frame_with_minibuf = Qnil;

                set_console_last_nonminibuf_frame(con, Qnil);

                CONSOLE_FRAME_LOOP_NO_BREAK(frmcons, devcons, con) {
                        Lisp_Object this;
                        struct frame *f1;

                        this = XCAR(frmcons);
                        f1 = XFRAME(this);

                        /* Consider only frames on the same console
                           and only those with minibuffers.  */
                        if (FRAME_HAS_MINIBUF_P(f1)) {
                                frame_with_minibuf = this;
                                if (FRAME_MINIBUF_ONLY_P(f1))
                                        goto double_break_2;
                        }

                        frame_on_same_console = this;
                }
              double_break_2:

                if (!NILP(frame_on_same_console)) {
                        /* We know that there must be some frame with a minibuffer out
                           there.  If this were not true, all of the frames present
                           would have to be minibuffer-less, which implies that at some
                           point their minibuffer frames must have been deleted, but
                           that is prohibited at the top; you can't delete surrogate
                           minibuffer frames.  */
                        if (NILP(frame_with_minibuf))
                                abort();

                        con->default_minibuffer_frame = frame_with_minibuf;
                } else
                        /* No frames left on this console--say no minibuffer either.  */
                        con->default_minibuffer_frame = Qnil;
        }

        nuke_all_frame_slots(f);        /* nobody should be accessing the device
                                           or anything else any more, and making
                                           them Qnil allows for better GC'ing
                                           in case a pointer to the dead frame
                                           continues to hang around. */
        f->framemeths = dead_console_methods;
        UNGCPRO;
}

void io_error_delete_frame(Lisp_Object frame)
{
        delete_frame_internal(XFRAME(frame), 1, 0, 1);
}

DEFUN("delete-frame", Fdelete_frame, 0, 2, "",  /*
Delete FRAME, permanently eliminating it from use.
If omitted, FRAME defaults to the selected frame.
A frame may not be deleted if its minibuffer is used by other frames.
Normally, you cannot delete the last non-minibuffer-only frame (you must
use `save-buffers-kill-emacs' or `kill-emacs').  However, if optional
second argument FORCE is non-nil, you can delete the last frame. (This
will automatically call `save-buffers-kill-emacs'.)
*/
      (frame, force))
{
        /* This function can GC */
        struct frame *f;

        if (NILP(frame)) {
                f = selected_frame();
                XSETFRAME(frame, f);
        } else {
                CHECK_FRAME(frame);
                f = XFRAME(frame);
        }

        delete_frame_internal(f, !NILP(force), 0, 0);
        return Qnil;
}
\f
/* Return mouse position in character cell units.  */

static int
mouse_pixel_position_1(struct device *d, Lisp_Object * frame, int *x, int *y)
{
        switch (DEVMETH_OR_GIVEN(d, get_mouse_position, (d, frame, x, y), -1)) {
        case 1:
                return 1;

        case 0:
                *frame = Qnil;
                break;

        case -1:
                *frame = DEVICE_SELECTED_FRAME(d);
                break;

        default:
                abort();        /* method is incorrectly written */
        }

        return 0;
}

DEFUN("mouse-pixel-position", Fmouse_pixel_position, 0, 1, 0,   /*
Return a list (WINDOW X . Y) giving the current mouse window and position.
The position is given in pixel units, where (0, 0) is the upper-left corner
of the