src/frame.h

   1 /* Define frame-object for GNU Emacs.
   2    Copyright (C) 1993, 1994 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Emacs.
   5
   6 GNU Emacs is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Emacs is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Emacs; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20 \f
  21 /* Miscellanea.  */
  22
  23 /* Nonzero means don't assume anything about current
  24    contents of actual terminal frame */
  25 extern int frame_garbaged;
  26
  27 /* Nonzero means FRAME_MESSAGE_BUF (selected_frame) is being used by
  28    print.  */
  29 extern int message_buf_print;
  30
  31 \f
  32 /* The structure representing a frame.
  33
  34    We declare this even if MULTI_FRAME is not defined, because when
  35    we lack multi-frame support, we use one instance of this structure
  36    to represent the one frame we support.  This is cleaner than
  37    having miscellaneous random variables scattered about.  */
  38
  39 enum output_method
  40 { output_termcap, output_x_window, output_msdos_raw };
  41
  42 struct frame
  43 {
  44   EMACS_INT size;
  45   struct Lisp_Vector *next;
  46
  47   /* All Lisp_Object components must come first.
  48      Only EMACS_INT values can be intermixed with them.
  49      That ensures they are all aligned normally.  */
  50
  51   /* Name of this frame: a Lisp string.  See also `explicit_name'
  52      and `namebuf'.  */
  53   Lisp_Object name;
  54
  55   /* The name to use for the icon, the last time
  56      it was refreshed.  nil means not explicitly specified.  */
  57   Lisp_Object icon_name;
  58
  59   /* The frame which should receive keystrokes that occur in this
  60      frame, or nil if they should go to the frame itself.  This is
  61      usually nil, but if the frame is minibufferless, we can use this
  62      to redirect keystrokes to a surrogate minibuffer frame when
  63      needed.
  64
  65      Note that a value of nil is different than having the field point
  66      to the frame itself.  Whenever the Fselect_frame function is used
  67      to shift from one frame to the other, any redirections to the
  68      original frame are shifted to the newly selected frame; if
  69      focus_frame is nil, Fselect_frame will leave it alone.  */
  70   Lisp_Object focus_frame;
  71
  72   /* This frame's root window.  Every frame has one.
  73      If the frame has only a minibuffer window, this is it.
  74      Otherwise, if the frame has a minibuffer window, this is its sibling.  */
  75   Lisp_Object root_window;
  76
  77   /* This frame's selected window.
  78      Each frame has its own window hierarchy
  79      and one of the windows in it is selected within the frame.
  80      The selected window of the selected frame is Emacs's selected window.  */
  81   Lisp_Object selected_window;
  82
  83   /* This frame's minibuffer window.
  84      Most frames have their own minibuffer windows,
  85      but only the selected frame's minibuffer window
  86      can actually appear to exist.  */
  87   Lisp_Object minibuffer_window;
  88
  89   /* Parameter alist of this frame.
  90      These are the parameters specified when creating the frame
  91      or modified with modify-frame-parameters.  */
  92   Lisp_Object param_alist;
  93
  94   /* List of scroll bars on this frame.
  95      Actually, we don't specify exactly what is stored here at all; the
  96      scroll bar implementation code can use it to store anything it likes.
  97      This field is marked by the garbage collector.  It is here
  98      instead of in the `display' structure so that the garbage
  99      collector doesn't need to look inside the window-system-dependent
 100      structure.  */
 101   Lisp_Object scroll_bars;
 102   Lisp_Object condemned_scroll_bars;
 103
 104   /* List of elements to display in the menu bar.
 105      The elements have the form (KEY STRING . nil) to start;
 106      when they are displayed, the hpos of the left edge goes in the cddr.  */
 107   Lisp_Object menu_bar_items;
 108
 109   /* Alist of elements (FACE-NAME . FACE-VECTOR-DATA).  */
 110   Lisp_Object face_alist;
 111
 112   /* A vector that records the entire structure of this frame's menu bar.
 113      For the format of the data, see extensive comments in xmenu.c.
 114      Only the X toolkit version uses this.  */
 115   Lisp_Object menu_bar_vector;
 116   /* Number of elements in the vector that have meaningful data.  */
 117   EMACS_INT menu_bar_items_used;
 118
 119   /* Predicate for selecting buffers for other-buffer.  */
 120   Lisp_Object buffer_predicate;
 121
 122   /* Beyond here, there should be no more Lisp_Object components.  */
 123
 124
 125   /* A buffer to hold the frame's name.  We can't use the Lisp string's
 126      pointer (`name', above) because it might get relocated.  */
 127   char *namebuf;
 128
 129   /* glyphs as they appear on the frame */
 130   struct frame_glyphs *current_glyphs;
 131
 132   /* glyphs we'd like to appear on the frame */
 133   struct frame_glyphs *desired_glyphs;
 134
 135   /* See do_line_insertion_deletion_costs for info on these arrays. */
 136   /* Cost of inserting 1 line on this frame */
 137   int *insert_line_cost;
 138   /* Cost of deleting 1 line on this frame */
 139   int *delete_line_cost;
 140   /* Cost of inserting n lines on this frame */
 141   int *insert_n_lines_cost;
 142   /* Cost of deleting n lines on this frame */
 143   int *delete_n_lines_cost;
 144
 145   /* glyphs for the mode line */
 146   struct frame_glyphs *temp_glyphs;
 147
 148   /* Intended cursor position of this frame.
 149      Measured in characters, counting from upper left corner
 150      within the frame.  */
 151   int cursor_x;
 152   int cursor_y;
 153
 154   /* Actual cursor position of this frame, and the character under it.
 155      (Not used for terminal frames.)  */
 156   int phys_cursor_x;
 157   int phys_cursor_y;
 158   /* This is handy for undrawing the cursor, because current_glyphs is
 159      not always accurate when in do_scrolling.  */
 160   GLYPH phys_cursor_glyph;
 161
 162   /* Size of this frame, in units of characters.  */
 163   EMACS_INT height;
 164   EMACS_INT width;
 165
 166   /* New height and width for pending size change.  0 if no change pending.  */
 167   int new_height, new_width;
 168
 169   /* The output method says how the contents of this frame
 170      are displayed.  It could be using termcap, or using an X window.  */
 171   enum output_method output_method;
 172
 173   /* A structure of auxiliary data used for displaying the contents.
 174      struct x_output is used for X window frames;
 175      it is defined in xterm.h.  */
 176   union output_data { struct x_output *x; int nothing; } output_data;
 177
 178 #ifdef MULTI_KBOARD
 179   /* A pointer to the kboard structure associated with this frame.
 180      For termcap frames, this points to initial_kboard.  For X frames,
 181      it will be the same as display.x->display_info->kboard.  */
 182   struct kboard *kboard;
 183 #endif
 184
 185   /* Number of lines of menu bar.  */
 186   int menu_bar_lines;
 187
 188 #ifdef USE_X_TOOLKIT
 189   /* Nonzero means using a menu bar that comes from the X toolkit.  */
 190   int external_menu_bar;
 191 #endif
 192
 193   /* Nonzero if last attempt at redisplay on this frame was preempted.  */
 194   char display_preempted;
 195
 196   /* visible is nonzero if the frame is currently displayed; we check
 197      it to see if we should bother updating the frame's contents.
 198      DON'T SET IT DIRECTLY; instead, use FRAME_SET_VISIBLE.
 199
 200      Note that, since invisible frames aren't updated, whenever a
 201      frame becomes visible again, it must be marked as garbaged.  The
 202      FRAME_SAMPLE_VISIBILITY macro takes care of this.
 203
 204      iconified is nonzero if the frame is currently iconified.
 205
 206      Asynchronous input handlers should NOT change these directly;
 207      instead, they should change async_visible or async_iconified, and
 208      let the FRAME_SAMPLE_VISIBILITY macro set visible and iconified
 209      at the next redisplay.
 210
 211      These should probably be considered read-only by everyone except
 212      FRAME_SAMPLE_VISIBILITY.
 213
 214      These two are mutually exclusive.  They might both be zero, if the
 215      frame has been made invisible without an icon.  */
 216   char visible, iconified;
 217
 218   /* Asynchronous input handlers change these, and
 219      FRAME_SAMPLE_VISIBILITY copies them into visible and iconified.
 220      See FRAME_SAMPLE_VISIBILITY, below.  */
 221 #ifdef __STDC__
 222   volatile
 223 #endif
 224   char async_visible, async_iconified;
 225
 226   /* Nonzero if this frame should be redrawn.  */
 227 #ifdef __STDC__
 228   volatile
 229 #endif
 230   char garbaged;
 231
 232   /* True if frame actually has a minibuffer window on it.
 233      0 if using a minibuffer window that isn't on this frame.  */
 234   char has_minibuffer;
 235
 236   /* 0 means, if this frame has just one window,
 237      show no modeline for that window.  */
 238   char wants_modeline;
 239
 240   /* Non-zero if the hardware device this frame is displaying on can
 241      support scroll bars.  */
 242   char can_have_scroll_bars;
 243
 244   /* If can_have_scroll_bars is non-zero, this is non-zero if we should
 245      actually display them on this frame.  */
 246   char has_vertical_scroll_bars;
 247
 248   /* Non-0 means raise this frame to the top of the heap when selected.  */
 249   char auto_raise;
 250
 251   /* Non-0 means lower this frame to the bottom of the stack when left.  */
 252   char auto_lower;
 253
 254   /* True if frame's root window can't be split.  */
 255   char no_split;
 256
 257   /* If this is set, then Emacs won't change the frame name to indicate
 258      the current buffer, etcetera.  If the user explicitly sets the frame
 259      name, this gets set.  If the user sets the name to Qnil, this is
 260      cleared.  */
 261   char explicit_name;
 262
 263   /* Nonzero if size of some window on this frame has changed.  */
 264   char window_sizes_changed;
 265
 266   /* Storage for messages to this frame. */
 267   char *message_buf;
 268
 269   /* Nonnegative if current redisplay should not do scroll computation
 270      for lines beyond a certain vpos.  This is the vpos.  */
 271   int scroll_bottom_vpos;
 272
 273   /* Width of the scroll bar, in pixels and in characters.
 274      scroll_bar_cols tracks scroll_bar_pixel_width if the latter is positive;
 275      a zero value in scroll_bar_pixel_width means to compute the actual width
 276      on the fly, using scroll_bar_cols and the current font width.  */
 277   int scroll_bar_pixel_width;
 278   int scroll_bar_cols;
 279
 280   /* The baud rate that was used to calculate costs for this frame.  */
 281   int cost_calculation_baud_rate;
 282
 283   /* Nonzero if the mouse has moved on this display
 284      since the last time we checked.  */
 285   char mouse_moved;
 286 };
 287
 288 #ifdef MULTI_KBOARD  /* Note that MULTI_KBOARD implies MULTI_FRAME */
 289 #define FRAME_KBOARD(f) ((f)->kboard)
 290 #else
 291 #define FRAME_KBOARD(f) (&the_only_kboard)
 292 #endif
 293
 294 #ifdef MULTI_FRAME
 295
 296 typedef struct frame *FRAME_PTR;
 297
 298 #define XFRAME(p) ((struct frame *) XPNTR (p))
 299 #define XSETFRAME(a, b) (XSETPSEUDOVECTOR (a, b, PVEC_FRAME))
 300
 301 #define WINDOW_FRAME(w) (w)->frame
 302
 303 #define FRAME_LIVE_P(f) ((f)->output_data.nothing != 0)
 304 #define FRAME_TERMCAP_P(f) ((f)->output_method == output_termcap)
 305 #define FRAME_X_P(f) ((f)->output_method == output_x_window)
 306 #define FRAME_MINIBUF_ONLY_P(f) \
 307   EQ (FRAME_ROOT_WINDOW (f), FRAME_MINIBUF_WINDOW (f))
 308 #define FRAME_HAS_MINIBUF_P(f) ((f)->has_minibuffer)
 309 #define FRAME_CURRENT_GLYPHS(f) (f)->current_glyphs
 310 #define FRAME_DESIRED_GLYPHS(f) (f)->desired_glyphs
 311 #define FRAME_TEMP_GLYPHS(f) (f)->temp_glyphs
 312 #define FRAME_HEIGHT(f) (f)->height
 313 #define FRAME_WIDTH(f) (f)->width
 314 #define FRAME_NEW_HEIGHT(f) (f)->new_height
 315 #define FRAME_NEW_WIDTH(f) (f)->new_width
 316 #define FRAME_MENU_BAR_LINES(f) (f)->menu_bar_lines
 317 #ifdef USE_X_TOOLKIT
 318 #define FRAME_EXTERNAL_MENU_BAR(f) (f)->external_menu_bar
 319 #else
 320 #define FRAME_EXTERNAL_MENU_BAR(f) 0
 321 #endif
 322 #define FRAME_CURSOR_X(f) (f)->cursor_x
 323 #define FRAME_CURSOR_Y(f) (f)->cursor_y
 324 #define FRAME_VISIBLE_P(f) ((f)->visible != 0)
 325 #define FRAME_SET_VISIBLE(f,p) \
 326   ((f)->async_visible = (p), FRAME_SAMPLE_VISIBILITY (f))
 327 #define SET_FRAME_GARBAGED(f) (frame_garbaged = 1, f->garbaged = 1)
 328 #define FRAME_GARBAGED_P(f) (f)->garbaged
 329 #define FRAME_NO_SPLIT_P(f) (f)->no_split
 330 #define FRAME_WANTS_MODELINE_P(f) (f)->wants_modeline
 331 #define FRAME_ICONIFIED_P(f) (f)->iconified
 332 #define FRAME_WINDOW_SIZES_CHANGED(f) (f)->window_sizes_changed
 333 #define FRAME_MINIBUF_WINDOW(f) (f)->minibuffer_window
 334 #define FRAME_ROOT_WINDOW(f) (f)->root_window
 335 #define FRAME_SELECTED_WINDOW(f) (f)->selected_window
 336 #define SET_GLYPHS_FRAME(glyphs,frame) ((glyphs)->frame = (frame))
 337 #define FRAME_INSERT_COST(f) (f)->insert_line_cost
 338 #define FRAME_DELETE_COST(f) (f)->delete_line_cost
 339 #define FRAME_INSERTN_COST(f) (f)->insert_n_lines_cost
 340 #define FRAME_DELETEN_COST(f) (f)->delete_n_lines_cost
 341 #define FRAME_MESSAGE_BUF(f) (f)->message_buf
 342 #define FRAME_SCROLL_BOTTOM_VPOS(f) (f)->scroll_bottom_vpos
 343 #define FRAME_FOCUS_FRAME(f) (f)->focus_frame
 344 #define FRAME_CAN_HAVE_SCROLL_BARS(f) ((f)->can_have_scroll_bars)
 345 #define FRAME_HAS_VERTICAL_SCROLL_BARS(f) ((f)->has_vertical_scroll_bars)
 346 #define FRAME_SCROLL_BAR_PIXEL_WIDTH(f) ((f)->scroll_bar_pixel_width)
 347 #define FRAME_SCROLL_BAR_COLS(f) ((f)->scroll_bar_cols)
 348 #define FRAME_SCROLL_BARS(f) ((f)->scroll_bars)
 349 #define FRAME_CONDEMNED_SCROLL_BARS(f) ((f)->condemned_scroll_bars)
 350 #define FRAME_MENU_BAR_ITEMS(f) ((f)->menu_bar_items)
 351 #define FRAME_COST_BAUD_RATE(f) ((f)->cost_calculation_baud_rate)
 352
 353 /* Emacs's redisplay code could become confused if a frame's
 354    visibility changes at arbitrary times.  For example, if a frame is
 355    visible while the desired glyphs are being built, but becomes
 356    invisible before they are updated, then some rows of the
 357    desired_glyphs will be left marked as enabled after redisplay is
 358    complete, which should never happen.  The next time the frame
 359    becomes visible, redisplay will probably barf.
 360
 361    Currently, there are no similar situations involving iconified, but
 362    the principle is the same.
 363
 364    So instead of having asynchronous input handlers directly set and
 365    clear the frame's visibility and iconification flags, they just set
 366    the async_visible and async_iconified flags; the redisplay code
 367    calls the FRAME_SAMPLE_VISIBILITY macro before doing any redisplay,
 368    which sets visible and iconified from their asynchronous
 369    counterparts.
 370
 371    Synchronous code must use the FRAME_SET_VISIBLE macro.
 372
 373    Also, if a frame used to be invisible, but has just become visible,
 374    it must be marked as garbaged, since redisplay hasn't been keeping
 375    up its contents.  */
 376 #define FRAME_SAMPLE_VISIBILITY(f) \
 377   (((f)->async_visible && ! (f)->visible) ? SET_FRAME_GARBAGED (f) : 0, \
 378    (f)->visible = (f)->async_visible, \
 379    (f)->iconified = (f)->async_iconified)
 380
 381 #define CHECK_FRAME(x, i)                               \
 382   {                                                     \
 383     if (! FRAMEP (x))                                   \
 384       x = wrong_type_argument (Qframep, (x));           \
 385   }
 386
 387 #define CHECK_LIVE_FRAME(x, i)                          \
 388   {                                                     \
 389     if (! FRAMEP (x)                                    \
 390         || ! FRAME_LIVE_P (XFRAME (x)))         \
 391       x = wrong_type_argument (Qframe_live_p, (x));     \
 392   }
 393
 394 /* FOR_EACH_FRAME (LIST_VAR, FRAME_VAR) followed by a statement is a
 395    `for' loop which iterates over the elements of Vframe_list.  The
 396    loop will set FRAME_VAR, a Lisp_Object, to each frame in
 397    Vframe_list in succession and execute the statement.  LIST_VAR
 398    should be a Lisp_Object too; it is used to iterate through the
 399    Vframe_list.
 400
 401    If MULTI_FRAME isn't defined, then this loop expands to something which
 402    executes the statement once.  */
 403 #define FOR_EACH_FRAME(list_var, frame_var)                     \
 404   for ((list_var) = Vframe_list;                                \
 405        (CONSP (list_var)                                        \
 406         && (frame_var = XCONS (list_var)->car, 1));             \
 407        list_var = XCONS (list_var)->cdr)
 408
 409
 410 extern Lisp_Object Qframep, Qframe_live_p, Qicon;
 411
 412 extern struct frame *selected_frame;
 413 extern struct frame *last_nonminibuf_frame;
 414
 415 extern struct frame *make_terminal_frame ();
 416 extern struct frame *make_frame ();
 417 extern struct frame *make_minibuffer_frame ();
 418 extern struct frame *make_frame_without_minibuffer ();
 419
 420 extern Lisp_Object Vframe_list;
 421 extern Lisp_Object Vdefault_frame_alist;
 422
 423 extern Lisp_Object Vterminal_frame;
 424 \f
 425 #else /* not MULTI_FRAME */
 426
 427 /* These definitions are used in a single-frame version of Emacs.  */
 428
 429 /* A frame we use to store all the data concerning the screen when we
 430    don't have multiple frames.  Remember, if you store any data in it
 431    which needs to be protected from GC, you should staticpro that
 432    element explicitly.  */
 433 extern struct frame the_only_frame;
 434
 435 typedef struct frame *FRAME_PTR;
 436 #ifdef __GNUC__
 437 /* A function call for always getting 0 is overkill, so... */
 438 #define WINDOW_FRAME(w) ({ Lisp_Object tem; XSETFASTINT (tem, 0); tem; })
 439 #else
 440 #define WINDOW_FRAME(w) (Fselected_frame ())
 441 #endif
 442 #define XSETFRAME(p, v) (p = WINDOW_FRAME (***bogus***))
 443 #define XFRAME(frame) (&the_only_frame)
 444
 445 extern FRAME_PTR selected_frame;
 446 extern FRAME_PTR last_nonminibuf_frame;
 447
 448 #define FRAME_LIVE_P(f) 1
 449 #ifdef MSDOS
 450 /* The following definitions could also be used in the non-MSDOS case,
 451    but the constants below lead to better code.  */
 452 #define FRAME_TERMCAP_P(f) (the_only_frame.output_method == output_termcap)
 453 #define FRAME_X_P(f) (the_only_frame.output_method != output_termcap)
 454 #else
 455 #define FRAME_TERMCAP_P(f) 1
 456 #define FRAME_X_P(f) 0
 457 #endif
 458 #define FRAME_MINIBUF_ONLY_P(f) 0
 459 #define FRAME_HAS_MINIBUF_P(f) 1
 460 #define FRAME_CURRENT_GLYPHS(f) (the_only_frame.current_glyphs)
 461 #define FRAME_DESIRED_GLYPHS(f) (the_only_frame.desired_glyphs)
 462 #define FRAME_TEMP_GLYPHS(f) (the_only_frame.temp_glyphs)
 463 #define FRAME_HEIGHT(f) (the_only_frame.height)
 464 #define FRAME_WIDTH(f) (the_only_frame.width)
 465 #define FRAME_NEW_HEIGHT(f) (the_only_frame.new_height)
 466 #define FRAME_NEW_WIDTH(f) (the_only_frame.new_width)
 467 #define FRAME_MENU_BAR_LINES(f) (the_only_frame.menu_bar_lines)
 468 #define FRAME_CURSOR_X(f) (the_only_frame.cursor_x)
 469 #define FRAME_CURSOR_Y(f) (the_only_frame.cursor_y)
 470 #define FRAME_SET_VISIBLE(f,p) (p)
 471 #define FRAME_VISIBLE_P(f) 1
 472 #define SET_FRAME_GARBAGED(f) (frame_garbaged = 1)
 473 #define FRAME_GARBAGED_P(f) (frame_garbaged)
 474 #define FRAME_NO_SPLIT_P(f) 0
 475 #define FRAME_WANTS_MODELINE_P(f) 1
 476 #define FRAME_ICONIFIED_P(f) 0
 477 #define FRAME_WINDOW_SIZES_CHANGED(f) the_only_frame.window_sizes_changed
 478 #define FRAME_MINIBUF_WINDOW(f) (minibuf_window)
 479 #define FRAME_ROOT_WINDOW(f) (the_only_frame.root_window)
 480 #define FRAME_SELECTED_WINDOW(f) (selected_window)
 481 #define SET_GLYPHS_FRAME(glyphs,frame) do ; while (0)
 482 #define FRAME_INSERT_COST(frame)  (the_only_frame.insert_line_cost)
 483 #define FRAME_DELETE_COST(frame)  (the_only_frame.delete_line_cost)
 484 #define FRAME_INSERTN_COST(frame) (the_only_frame.insert_n_lines_cost)
 485 #define FRAME_DELETEN_COST(frame) (the_only_frame.delete_n_lines_cost)
 486 #define FRAME_MESSAGE_BUF(f) (the_only_frame.message_buf)
 487 #define FRAME_SCROLL_BOTTOM_VPOS(f) (the_only_frame.scroll_bottom_vpos)
 488 #define FRAME_FOCUS_FRAME(f) (Qnil)
 489 #define FRAME_CAN_HAVE_SCROLL_BARS(f) (the_only_frame.can_have_scroll_bars)
 490 #define FRAME_HAS_VERTICAL_SCROLL_BARS(f) \
 491   (the_only_frame.has_vertical_scroll_bars)
 492 #define FRAME_SCROLL_BAR_PIXEL_WIDTH(f) (the_only_frame.scroll_bar_pixel_width)
 493 #define FRAME_SCROLL_BAR_COLS(f) (the_only_frame.scroll_bar_cols)
 494 #define FRAME_SCROLL_BARS(f) (the_only_frame.scroll_bars)
 495 #define FRAME_CONDEMNED_SCROLL_BARS(f) (the_only_frame.condemned_scroll_bars)
 496 #define FRAME_MENU_BAR_ITEMS(f) (the_only_frame.menu_bar_items)
 497 #define FRAME_COST_BAUD_RATE(f) (the_only_frame.cost_calculation_baud_rate)
 498
 499 /* See comments in definition above.  */
 500 #define FRAME_SAMPLE_VISIBILITY(f) (0)
 501
 502 #define CHECK_FRAME(x, i) do; while (0)
 503 #define CHECK_LIVE_FRAME(x, y) do; while (0)
 504
 505 /* FOR_EACH_FRAME (LIST_VAR, FRAME_VAR) followed by a statement is a
 506    `for' loop which iterates over the elements of Vframe_list.  The
 507    loop will set FRAME_VAR, a Lisp_Object, to each frame in
 508    Vframe_list in succession and execute the statement.  LIST_VAR
 509    should be a Lisp_Object too; it is used to iterate through the
 510    Vframe_list.
 511
 512    If MULTI_FRAME _is_ defined, then this loop expands to a real
 513    `for' loop which traverses Vframe_list using LIST_VAR and
 514    FRAME_VAR.  */
 515 #define FOR_EACH_FRAME(list_var, frame_var)                     \
 516   for (list_var = Qt; frame_var = WINDOW_FRAME (***bogus***), ! NILP (list_var); list_var = Qnil)
 517
 518 #endif /* not MULTI_FRAME */
 519
 520 \f
 521 /* Device- and MULTI_FRAME-independent scroll bar stuff.  */
 522
 523 /* Return the starting column (zero-based) of the vertical scroll bar
 524    for window W.  The column before this one is the last column we can
 525    use for text.  If the window touches the right edge of the frame,
 526    we have extra space allocated for it.  Otherwise, the scroll bar
 527    takes over the window's rightmost columns.  */
 528 #define WINDOW_VERTICAL_SCROLL_BAR_COLUMN(w) \
 529   (((XINT ((w)->left) + XINT ((w)->width)) \
 530     < FRAME_WIDTH (XFRAME (WINDOW_FRAME (w)))) \
 531    ? (XINT ((w)->left) + XINT ((w)->width) \
 532       - FRAME_SCROLL_BAR_COLS (XFRAME (WINDOW_FRAME (w)))) \
 533    : FRAME_WIDTH (XFRAME (WINDOW_FRAME (w))))
 534
 535 /* Return the height in lines of the vertical scroll bar in w.  If the
 536    window has a mode line, don't make the scroll bar extend that far.  */
 537 #define WINDOW_VERTICAL_SCROLL_BAR_HEIGHT(w) (window_internal_height (w))