src/window.h

   1 /* Window definitions for GNU Emacs.
   2    Copyright (C) 1985, 1986, 1993, 1995 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, Inc., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21 #ifndef WINDOW_H_INCLUDED
  22 #define WINDOW_H_INCLUDED
  23
  24 #include "dispextern.h"
  25
  26 /* Windows are allocated as if they were vectors, but then the
  27 Lisp data type is changed to Lisp_Window.  They are garbage
  28 collected along with the vectors.
  29
  30 All windows in use are arranged into a tree, with pointers up and down.
  31
  32 Windows that are leaves of the tree are actually displayed
  33 and show the contents of buffers.  Windows that are not leaves
  34 are used for representing the way groups of leaf windows are
  35 arranged on the frame.  Leaf windows never become non-leaves.
  36 They are deleted only by calling delete-window on them (but
  37 this can be done implicitly).  Combination windows can be created
  38 and deleted at any time.
  39
  40 A leaf window has a non-nil buffer field, and also
  41  has markers in its start and pointm fields.  Non-leaf windows
  42  have nil in these fields.
  43
  44 Non-leaf windows are either vertical or horizontal combinations.
  45
  46 A vertical combination window has children that are arranged on the frame
  47 one above the next.  Its vchild field points to the uppermost child.
  48 The parent field of each of the children points to the vertical
  49 combination window.  The next field of each child points to the
  50 child below it, or is nil for the lowest child.  The prev field
  51 of each child points to the child above it, or is nil for the
  52 highest child.
  53
  54 A horizontal combination window has children that are side by side.
  55 Its hchild field points to the leftmost child.  In each child
  56 the next field points to the child to the right and the prev field
  57 points to the child to the left.
  58
  59 The children of a vertical combination window may be leaf windows
  60 or horizontal combination windows.  The children of a horizontal
  61 combination window may be leaf windows or vertical combination windows.
  62
  63 At the top of the tree are two windows which have nil as parent.
  64 The second of these is minibuf_window.  The first one manages all
  65 the frame area that is not minibuffer, and is called the root window.
  66 Different windows can be the root at different times;
  67 initially the root window is a leaf window, but if more windows
  68 are created then that leaf window ceases to be root and a newly
  69 made combination window becomes root instead.
  70
  71 In any case, on screens which have an ordinary window and a
  72 minibuffer, prev of the minibuf window is the root window and next of
  73 the root window is the minibuf window.  On minibufferless screens or
  74 minibuffer-only screens, the root window and the minibuffer window are
  75 one and the same, so its prev and next members are nil.
  76
  77 A dead window has its buffer, hchild, and vchild windows all nil.  */
  78
  79 struct cursor_pos
  80 {
  81   /* Pixel position.  These are always window relative.  */
  82   int x, y;
  83
  84   /* Glyph matrix position.  */
  85   int hpos, vpos;
  86 };
  87
  88 struct window
  89   {
  90     /* The first two fields are really the header of a vector */
  91     /* The window code does not refer to them.  */
  92     EMACS_INT size;
  93     struct Lisp_Vector *vec_next;
  94     /* The frame this window is on.  */
  95     Lisp_Object frame;
  96     /* t if this window is a minibuffer window.  */
  97     Lisp_Object mini_p;
  98     /* Following child (to right or down) at same level of tree */
  99     Lisp_Object next;
 100     /* Preceding child (to left or up) at same level of tree */
 101     Lisp_Object prev;
 102     /* First child of this window. */
 103     /* vchild is used if this is a vertical combination,
 104        hchild if this is a horizontal combination. */
 105     Lisp_Object hchild, vchild;
 106     /* The window this one is a child of. */
 107     Lisp_Object parent;
 108     /* The upper left corner coordinates of this window,
 109        as integers relative to upper left corner of frame = 0, 0 */
 110     Lisp_Object left;
 111     Lisp_Object top;
 112     /* The size of the window */
 113     Lisp_Object height;
 114     Lisp_Object width;
 115     /* The buffer displayed in this window */
 116     /* Of the fields vchild, hchild and buffer, only one is non-nil.  */
 117     Lisp_Object buffer;
 118     /* A marker pointing to where in the text to start displaying */
 119     Lisp_Object start;
 120     /* A marker pointing to where in the text point is in this window,
 121        used only when the window is not selected.
 122        This exists so that when multiple windows show one buffer
 123        each one can have its own value of point.  */
 124     Lisp_Object pointm;
 125     /* Non-nil means next redisplay must use the value of start
 126        set up for it in advance.  Set by scrolling commands.  */
 127     Lisp_Object force_start;
 128     /* Non-nil means we have explicitly changed the value of start,
 129        but that the next redisplay is not obliged to use the new value.  */
 130     Lisp_Object optional_new_start;
 131     /* Number of columns display within the window is scrolled to the left.  */
 132     Lisp_Object hscroll;
 133     /* Number saying how recently window was selected */
 134     Lisp_Object use_time;
 135     /* Unique number of window assigned when it was created */
 136     Lisp_Object sequence_number;
 137     /* No permanent meaning; used by save-window-excursion's bookkeeping */
 138     Lisp_Object temslot;
 139     /* text.modified of displayed buffer as of last time display completed */
 140     Lisp_Object last_modified;
 141     /* BUF_OVERLAY_MODIFIED of displayed buffer as of last complete update.  */
 142     Lisp_Object last_overlay_modified;
 143     /* Value of point at that time */
 144     Lisp_Object last_point;
 145     /* Non-nil if the buffer was "modified" when the window
 146        was last updated.  */
 147     Lisp_Object last_had_star;
 148     /* This window's vertical scroll bar.  This field is only for use
 149        by the window-system-dependent code which implements the
 150        scroll bars; it can store anything it likes here.  If this
 151        window is newly created and we haven't displayed a scroll bar in
 152        it yet, or if the frame doesn't have any scroll bars, this is nil.  */
 153     Lisp_Object vertical_scroll_bar;
 154
 155     /* Width of left and right marginal areas.  A value of nil means
 156        no margin.  */
 157     Lisp_Object left_margin_width;
 158     Lisp_Object right_margin_width;
 159
 160 /* The rest are currently not used or only half used */
 161     /* Frame coords of mark as of last time display completed */
 162     /* May be nil if mark does not exist or was not on frame */
 163     Lisp_Object last_mark_x;
 164     Lisp_Object last_mark_y;
 165     /* Z - the buffer position of the last glyph in the current matrix
 166        of W.  Only valid if WINDOW_END_VALID is not nil.  */
 167     Lisp_Object window_end_pos;
 168     /* Glyph matrix row of the last glyph in the current matrix
 169        of W.  Only valid if WINDOW_END_VALID is not nil.  */
 170     Lisp_Object window_end_vpos;
 171     /* t if window_end_pos is truly valid.
 172        This is nil if nontrivial redisplay is preempted
 173        since in that case the frame image that window_end_pos
 174        did not get onto the frame.  */
 175     Lisp_Object window_end_valid;
 176     /* Non-nil means must regenerate mode line of this window */
 177     Lisp_Object update_mode_line;
 178     /* Non-nil means current value of `start'
 179        was the beginning of a line when it was chosen.  */
 180     Lisp_Object start_at_line_beg;
 181     /* Display-table to use for displaying chars in this window.
 182        Nil means use the buffer's own display-table.  */
 183     Lisp_Object display_table;
 184     /* Non-nil means window is marked as dedicated.  */
 185     Lisp_Object dedicated;
 186     /* Line number and position of a line somewhere above the
 187        top of the screen.  */
 188     /* If this field is nil, it means we don't have a base line.  */
 189     Lisp_Object base_line_number;
 190     /* If this field is nil, it means we don't have a base line.
 191        If it is a buffer, it means don't display the line number
 192        as long as the window shows that buffer.  */
 193     Lisp_Object base_line_pos;
 194     /* If we have highlighted the region (or any part of it),
 195        this is the mark position that we used, as an integer.  */
 196     Lisp_Object region_showing;
 197     /* The column number currently displayed in this window's mode line,
 198        or nil if column numbers are not being displayed.  */
 199     Lisp_Object column_number_displayed;
 200     /* If redisplay in this window goes beyond this buffer position,
 201        must run the redisplay-end-trigger-hook.  */
 202     Lisp_Object redisplay_end_trigger;
 203     /* Non-nil means don't delete this window for becoming "too small".  */
 204     Lisp_Object too_small_ok;
 205
 206     /* Original window height and top before mini-window was
 207        enlarged. */
 208     Lisp_Object orig_height, orig_top;
 209
 210     /* No Lisp data may follow below this point without changing
 211        mark_object in alloc.c.  The member current_matrix must be the
 212        first non-Lisp member.  */
 213
 214     /* Glyph matrices.  */
 215     struct glyph_matrix *current_matrix;
 216     struct glyph_matrix *desired_matrix;
 217
 218     /* Cursor position as of last update that completed without
 219        pause.  This is the position of last_point.  */
 220     struct cursor_pos last_cursor;
 221
 222     /* Intended cursor position.   This is a position within the
 223        glyph matrix.  */
 224     struct cursor_pos cursor;
 225
 226     /* Where the cursor actually is.  */
 227     struct cursor_pos phys_cursor;
 228
 229     /* Cursor type last drawn on the window.  Used for X frames; -1
 230        initially.  */
 231     int phys_cursor_type;
 232
 233     /* This is handy for undrawing the cursor.  */
 234     int phys_cursor_ascent, phys_cursor_height;
 235
 236     /* Non-zero means the cursor is currently displayed.  This can be
 237        set to zero by functions overpainting the cursor image.  */
 238     unsigned phys_cursor_on_p : 1;
 239
 240     /* 0 means cursor is logically on, 1 means it's off.  Used for
 241        blinking cursor.  */
 242     unsigned cursor_off_p : 1;
 243
 244     /* Value of cursor_off_p as of the last redisplay.  */
 245     unsigned last_cursor_off_p : 1;
 246
 247     /* 1 means desired matrix has been build and window must be
 248        updated in update_frame.  */
 249     unsigned must_be_updated_p : 1;
 250
 251     /* Flag indicating that this window is not a real one.
 252        Currently only used for menu bar windows of frames.  */
 253     unsigned pseudo_window_p : 1;
 254
 255     /* Amount by which lines of this window are scrolled in
 256        y-direction (smooth scrolling).  */
 257     int vscroll;
 258
 259     /* Z_BYTE - the buffer position of the last glyph in the current matrix
 260        of W.  Only valid if WINDOW_END_VALID is not nil.  */
 261     int window_end_bytepos;
 262
 263     /* 1 means the window start of this window is frozen and may not
 264        be changed during redisplay.  If point is not in the window,
 265        accept that.  */
 266     unsigned frozen_window_start_p : 1;
 267
 268     /* 1 means that this window's height is temporarily fixed.  Used
 269        in resize_mini_window to precent resizing selected_window, if
 270        possible.  */
 271     unsigned height_fixed_p : 1;
 272 };
 273
 274 /* 1 if W is a minibuffer window.  */
 275
 276 #define MINI_WINDOW_P(W)        (!EQ ((W)->mini_p, Qnil))
 277
 278 /* Return the window column at which the text in window W starts.
 279    This is different from the `left' field because it does not include
 280    a left-hand scroll bar if any.  */
 281
 282 #define WINDOW_LEFT_MARGIN(W) \
 283      (XFASTINT ((W)->left) \
 284       + FRAME_LEFT_SCROLL_BAR_WIDTH (XFRAME (WINDOW_FRAME (W))))
 285
 286 /* Return the window column before which window W ends.
 287    This includes a right-hand scroll bar, if any.  */
 288
 289 #define WINDOW_RIGHT_EDGE(W) \
 290      (XFASTINT ((W)->left) + XFASTINT ((W)->width))
 291
 292 /* Return the window column before which the text in window W ends.
 293    This is different from WINDOW_RIGHT_EDGE because it does not include
 294    a scroll bar or window-separating line on the right edge.  */
 295
 296 #define WINDOW_RIGHT_MARGIN(W) \
 297      (WINDOW_RIGHT_EDGE (W) \
 298       - (FRAME_HAS_VERTICAL_SCROLL_BARS_ON_RIGHT (XFRAME (WINDOW_FRAME (W))) \
 299          ? FRAME_SCROLL_BAR_COLS (XFRAME (WINDOW_FRAME (W))) \
 300          : 0))
 301
 302 /* 1 if window W takes up the full width of its frame.  */
 303
 304 #define WINDOW_FULL_WIDTH_P(W) \
 305      (XFASTINT ((W)->width) == FRAME_WINDOW_WIDTH (XFRAME (WINDOW_FRAME (W))))
 306
 307 /* 1 if window W's has no other windows to its right in its frame.  */
 308
 309 #define WINDOW_RIGHTMOST_P(W) \
 310      (WINDOW_RIGHT_EDGE (W) == FRAME_WINDOW_WIDTH (XFRAME (WINDOW_FRAME (W))))
 311
 312
 313 /* This is the window in which the terminal's cursor should
 314    be left when nothing is being done with it.  This must
 315    always be a leaf window, and its buffer is selected by
 316    the top level editing loop at the end of each command.
 317
 318    This value is always the same as
 319     FRAME_SELECTED_WINDOW (selected_frame).  */
 320
 321 extern Lisp_Object selected_window;
 322
 323 /* This is a time stamp for window selection, so we can find the least
 324    recently used window.  Its only users are Fselect_window,
 325    init_window_once, and make_frame.  */
 326
 327 extern int window_select_count;
 328
 329 /* The minibuffer window of the selected frame.
 330    Note that you cannot test for minibufferness of an arbitrary window
 331    by comparing against this; use the MINI_WINDOW_P macro instead.  */
 332
 333 extern Lisp_Object minibuf_window;
 334
 335 /* Non-nil => window to for C-M-v to scroll when the minibuffer is
 336    selected.  */
 337
 338 extern Lisp_Object Vminibuf_scroll_window;
 339
 340 /* Nil or a symbol naming the window system under which emacs is
 341    running ('x is the only current possibility) */
 342
 343 extern Lisp_Object Vwindow_system;
 344
 345 /* Version number of X windows: 10, 11 or nil.  */
 346
 347 extern Lisp_Object Vwindow_system_version;
 348
 349 /* Window that the mouse is over (nil if no mouse support).  */
 350
 351 extern Lisp_Object Vmouse_window;
 352
 353 /* Last mouse-click event (nil if no mouse support).  */
 354
 355 extern Lisp_Object Vmouse_event;
 356
 357 EXFUN (Fnext_window, 3);
 358 EXFUN (Fselect_window, 1);
 359 EXFUN (Fdisplay_buffer, 3);
 360 EXFUN (Fset_window_buffer, 2);
 361 EXFUN (Fset_window_hscroll, 2);
 362 EXFUN (Fwindow_hscroll, 1);
 363 EXFUN (Fset_window_vscroll, 2);
 364 EXFUN (Fwindow_vscroll, 1);
 365 EXFUN (Fset_window_margins, 3);
 366 extern Lisp_Object make_window P_ ((void));
 367 extern void delete_window P_ ((Lisp_Object));
 368 extern Lisp_Object window_from_coordinates P_ ((struct frame *, int, int, int *, int));
 369 EXFUN (Fwindow_dedicated_p, 1);
 370 extern int window_height P_ ((Lisp_Object));
 371 extern int window_width P_ ((Lisp_Object));
 372 extern void set_window_height P_ ((Lisp_Object, int, int));
 373 extern void set_window_width P_ ((Lisp_Object, int, int));
 374 extern void delete_all_subwindows P_ ((struct window *));
 375 extern void freeze_window_starts P_ ((struct frame *, int));
 376 extern void foreach_window ();
 377 extern void grow_mini_window P_ ((struct window *, int));
 378 extern void shrink_mini_window P_ ((struct window *));
 379
 380
 381 /* Make WINDOW display BUFFER as its contents.  RUN_HOOKS_P non-zero
 382    means it's allowed to run hooks.  See make_frame for a case where
 383    it's not allowed.  */
 384
 385 void set_window_buffer P_ ((Lisp_Object window, Lisp_Object buffer,
 386                             int run_hooks_p));
 387
 388 /* Prompt to display in front of the minibuffer contents.  */
 389
 390 extern Lisp_Object minibuf_prompt;
 391
 392 /* The visual width of the above.  */
 393
 394 extern int minibuf_prompt_width;
 395
 396 /* This is the window where the echo area message was displayed.  It
 397    is always a minibuffer window, but it may not be the same window
 398    currently active as a minibuffer.  */
 399
 400 extern Lisp_Object echo_area_window;
 401
 402 /* Depth in recursive edits.  */
 403
 404 extern int command_loop_level;
 405
 406 /* Depth in minibuffer invocations.  */
 407
 408 extern int minibuf_level;
 409
 410 /* true iff we should redraw the mode lines on the next redisplay.  */
 411
 412 extern int update_mode_lines;
 413
 414 /* Nonzero if BEGV - BEG or Z - ZV of current buffer has changed since
 415    last redisplay that finished.  */
 416
 417 extern int clip_changed;
 418
 419 /* Nonzero if window sizes or contents have changed since last
 420    redisplay that finished */
 421
 422 extern int windows_or_buffers_changed;
 423
 424 /* Number of windows displaying the selected buffer.  Normally this is
 425    1, but it can be more.  */
 426
 427 extern int buffer_shared;
 428
 429 /* If *ROWS or *COLS are too small a size for FRAME, set them to the
 430    minimum allowable size.  */
 431
 432 extern void check_frame_size P_ ((struct frame *frame, int *rows, int *cols));
 433
 434 /* Return a pointer to the glyph W's physical cursor is on.  Value is
 435    null if W's current matrix is invalid, so that no meaningfull glyph
 436    can be returned.  */
 437
 438 struct glyph *get_phys_cursor_glyph P_ ((struct window *w));
 439
 440 #endif /* not WINDOW_H_INCLUDED */