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        This is used in Fdelete_other_windows to force a call to
 131        Vwindow_scroll_functions.  */
 132     Lisp_Object optional_new_start;
 133     /* Number of columns display within the window is scrolled to the left.  */
 134     Lisp_Object hscroll;
 135     /* Number saying how recently window was selected */
 136     Lisp_Object use_time;
 137     /* Unique number of window assigned when it was created */
 138     Lisp_Object sequence_number;
 139     /* No permanent meaning; used by save-window-excursion's bookkeeping */
 140     Lisp_Object temslot;
 141     /* text.modified of displayed buffer as of last time display completed */
 142     Lisp_Object last_modified;
 143     /* BUF_OVERLAY_MODIFIED of displayed buffer as of last complete update.  */
 144     Lisp_Object last_overlay_modified;
 145     /* Value of point at that time */
 146     Lisp_Object last_point;
 147     /* Non-nil if the buffer was "modified" when the window
 148        was last updated.  */
 149     Lisp_Object last_had_star;
 150     /* This window's vertical scroll bar.  This field is only for use
 151        by the window-system-dependent code which implements the
 152        scroll bars; it can store anything it likes here.  If this
 153        window is newly created and we haven't displayed a scroll bar in
 154        it yet, or if the frame doesn't have any scroll bars, this is nil.  */
 155     Lisp_Object vertical_scroll_bar;
 156
 157     /* Width of left and right marginal areas.  A value of nil means
 158        no margin.  */
 159     Lisp_Object left_margin_width;
 160     Lisp_Object right_margin_width;
 161
 162 /* The rest are currently not used or only half used */
 163     /* Frame coords of mark as of last time display completed */
 164     /* May be nil if mark does not exist or was not on frame */
 165     Lisp_Object last_mark_x;
 166     Lisp_Object last_mark_y;
 167     /* Z - the buffer position of the last glyph in the current matrix
 168        of W.  Only valid if WINDOW_END_VALID is not nil.  */
 169     Lisp_Object window_end_pos;
 170     /* Glyph matrix row of the last glyph in the current matrix
 171        of W.  Only valid if WINDOW_END_VALID is not nil.  */
 172     Lisp_Object window_end_vpos;
 173     /* t if window_end_pos is truly valid.
 174        This is nil if nontrivial redisplay is preempted
 175        since in that case the frame image that window_end_pos
 176        did not get onto the frame.  */
 177     Lisp_Object window_end_valid;
 178     /* Non-nil means must regenerate mode line of this window */
 179     Lisp_Object update_mode_line;
 180     /* Non-nil means current value of `start'
 181        was the beginning of a line when it was chosen.  */
 182     Lisp_Object start_at_line_beg;
 183     /* Display-table to use for displaying chars in this window.
 184        Nil means use the buffer's own display-table.  */
 185     Lisp_Object display_table;
 186     /* Non-nil means window is marked as dedicated.  */
 187     Lisp_Object dedicated;
 188     /* Line number and position of a line somewhere above the
 189        top of the screen.  */
 190     /* If this field is nil, it means we don't have a base line.  */
 191     Lisp_Object base_line_number;
 192     /* If this field is nil, it means we don't have a base line.
 193        If it is a buffer, it means don't display the line number
 194        as long as the window shows that buffer.  */
 195     Lisp_Object base_line_pos;
 196     /* If we have highlighted the region (or any part of it),
 197        this is the mark position that we used, as an integer.  */
 198     Lisp_Object region_showing;
 199     /* The column number currently displayed in this window's mode line,
 200        or nil if column numbers are not being displayed.  */
 201     Lisp_Object column_number_displayed;
 202     /* If redisplay in this window goes beyond this buffer position,
 203        must run the redisplay-end-trigger-hook.  */
 204     Lisp_Object redisplay_end_trigger;
 205     /* Non-nil means don't delete this window for becoming "too small".  */
 206     Lisp_Object too_small_ok;
 207
 208     /* Original window height and top before mini-window was
 209        enlarged. */
 210     Lisp_Object orig_height, orig_top;
 211
 212     /* No Lisp data may follow below this point without changing
 213        mark_object in alloc.c.  The member current_matrix must be the
 214        first non-Lisp member.  */
 215
 216     /* Glyph matrices.  */
 217     struct glyph_matrix *current_matrix;
 218     struct glyph_matrix *desired_matrix;
 219
 220     /* Cursor position as of last update that completed without
 221        pause.  This is the position of last_point.  */
 222     struct cursor_pos last_cursor;
 223
 224     /* Intended cursor position.   This is a position within the
 225        glyph matrix.  */
 226     struct cursor_pos cursor;
 227
 228     /* Where the cursor actually is.  */
 229     struct cursor_pos phys_cursor;
 230
 231     /* Cursor type last drawn on the window.  Used for X frames; -1
 232        initially.  */
 233     int phys_cursor_type;
 234
 235     /* This is handy for undrawing the cursor.  */
 236     int phys_cursor_ascent, phys_cursor_height;
 237
 238     /* Non-zero means the cursor is currently displayed.  This can be
 239        set to zero by functions overpainting the cursor image.  */
 240     unsigned phys_cursor_on_p : 1;
 241
 242     /* 0 means cursor is logically on, 1 means it's off.  Used for
 243        blinking cursor.  */
 244     unsigned cursor_off_p : 1;
 245
 246     /* Value of cursor_off_p as of the last redisplay.  */
 247     unsigned last_cursor_off_p : 1;
 248
 249     /* 1 means desired matrix has been build and window must be
 250        updated in update_frame.  */
 251     unsigned must_be_updated_p : 1;
 252
 253     /* Flag indicating that this window is not a real one.
 254        Currently only used for menu bar windows of frames.  */
 255     unsigned pseudo_window_p : 1;
 256
 257     /* Amount by which lines of this window are scrolled in
 258        y-direction (smooth scrolling).  */
 259     int vscroll;
 260
 261     /* Z_BYTE - the buffer position of the last glyph in the current matrix
 262        of W.  Only valid if WINDOW_END_VALID is not nil.  */
 263     int window_end_bytepos;
 264
 265     /* 1 means the window start of this window is frozen and may not
 266        be changed during redisplay.  If point is not in the window,
 267        accept that.  */
 268     unsigned frozen_window_start_p : 1;
 269
 270     /* 1 means that this window's height is temporarily fixed.  Used
 271        in resize_mini_window to precent resizing selected_window, if
 272        possible.  */
 273     unsigned height_fixed_p : 1;
 274 };
 275
 276 /* 1 if W is a minibuffer window.  */
 277
 278 #define MINI_WINDOW_P(W)        (!EQ ((W)->mini_p, Qnil))
 279
 280 /* Return the window column at which the text in window W starts.
 281    This is different from the `left' field because it does not include
 282    a left-hand scroll bar if any.  */
 283
 284 #define WINDOW_LEFT_MARGIN(W) \
 285      (XFASTINT ((W)->left) \
 286       + FRAME_LEFT_SCROLL_BAR_WIDTH (XFRAME (WINDOW_FRAME (W))))
 287
 288 /* Return the window column before which window W ends.
 289    This includes a right-hand scroll bar, if any.  */
 290
 291 #define WINDOW_RIGHT_EDGE(W) \
 292      (XFASTINT ((W)->left) + XFASTINT ((W)->width))
 293
 294 /* Return the window column before which the text in window W ends.
 295    This is different from WINDOW_RIGHT_EDGE because it does not include
 296    a scroll bar or window-separating line on the right edge.  */
 297
 298 #define WINDOW_RIGHT_MARGIN(W) \
 299      (WINDOW_RIGHT_EDGE (W) \
 300       - (FRAME_HAS_VERTICAL_SCROLL_BARS_ON_RIGHT (XFRAME (WINDOW_FRAME (W))) \
 301          ? FRAME_SCROLL_BAR_COLS (XFRAME (WINDOW_FRAME (W))) \
 302          : 0))
 303
 304 /* 1 if window W takes up the full width of its frame.  */
 305
 306 #define WINDOW_FULL_WIDTH_P(W) \
 307      (XFASTINT ((W)->width) == FRAME_WINDOW_WIDTH (XFRAME (WINDOW_FRAME (W))))
 308
 309 /* 1 if window W's has no other windows to its right in its frame.  */
 310
 311 #define WINDOW_RIGHTMOST_P(W) \
 312      (WINDOW_RIGHT_EDGE (W) == FRAME_WINDOW_WIDTH (XFRAME (WINDOW_FRAME (W))))
 313
 314
 315 /* This is the window in which the terminal's cursor should
 316    be left when nothing is being done with it.  This must
 317    always be a leaf window, and its buffer is selected by
 318    the top level editing loop at the end of each command.
 319
 320    This value is always the same as
 321     FRAME_SELECTED_WINDOW (selected_frame).  */
 322
 323 extern Lisp_Object selected_window;
 324
 325 /* This is a time stamp for window selection, so we can find the least
 326    recently used window.  Its only users are Fselect_window,
 327    init_window_once, and make_frame.  */
 328
 329 extern int window_select_count;
 330
 331 /* The minibuffer window of the selected frame.
 332    Note that you cannot test for minibufferness of an arbitrary window
 333    by comparing against this; use the MINI_WINDOW_P macro instead.  */
 334
 335 extern Lisp_Object minibuf_window;
 336
 337 /* Non-nil => window to for C-M-v to scroll when the minibuffer is
 338    selected.  */
 339
 340 extern Lisp_Object Vminibuf_scroll_window;
 341
 342 /* Nil or a symbol naming the window system under which emacs is
 343    running ('x is the only current possibility) */
 344
 345 extern Lisp_Object Vwindow_system;
 346
 347 /* Version number of X windows: 10, 11 or nil.  */
 348
 349 extern Lisp_Object Vwindow_system_version;
 350
 351 /* Window that the mouse is over (nil if no mouse support).  */
 352
 353 extern Lisp_Object Vmouse_window;
 354
 355 /* Last mouse-click event (nil if no mouse support).  */
 356
 357 extern Lisp_Object Vmouse_event;
 358
 359 EXFUN (Fnext_window, 3);
 360 EXFUN (Fselect_window, 1);
 361 EXFUN (Fdisplay_buffer, 3);
 362 EXFUN (Fset_window_buffer, 2);
 363 EXFUN (Fset_window_hscroll, 2);
 364 EXFUN (Fwindow_hscroll, 1);
 365 EXFUN (Fset_window_vscroll, 2);
 366 EXFUN (Fwindow_vscroll, 1);
 367 EXFUN (Fset_window_margins, 3);
 368 extern Lisp_Object make_window P_ ((void));
 369 extern void delete_window P_ ((Lisp_Object));
 370 extern Lisp_Object window_from_coordinates P_ ((struct frame *, int, int, int *, int));
 371 EXFUN (Fwindow_dedicated_p, 1);
 372 extern int window_height P_ ((Lisp_Object));
 373 extern int window_width P_ ((Lisp_Object));
 374 extern void set_window_height P_ ((Lisp_Object, int, int));
 375 extern void set_window_width P_ ((Lisp_Object, int, int));
 376 extern void delete_all_subwindows P_ ((struct window *));
 377 extern void freeze_window_starts P_ ((struct frame *, int));
 378 extern void foreach_window P_ ((struct frame *,
 379                                 int (* fn) (struct window *, void *),
 380                                 void *));
 381 extern void grow_mini_window P_ ((struct window *, int));
 382 extern void shrink_mini_window P_ ((struct window *));
 383
 384
 385 /* Make WINDOW display BUFFER as its contents.  RUN_HOOKS_P non-zero
 386    means it's allowed to run hooks.  See make_frame for a case where
 387    it's not allowed.  */
 388
 389 void set_window_buffer P_ ((Lisp_Object window, Lisp_Object buffer,
 390                             int run_hooks_p));
 391
 392 /* Prompt to display in front of the minibuffer contents.  */
 393
 394 extern Lisp_Object minibuf_prompt;
 395
 396 /* The visual width of the above.  */
 397
 398 extern int minibuf_prompt_width;
 399
 400 /* This is the window where the echo area message was displayed.  It
 401    is always a minibuffer window, but it may not be the same window
 402    currently active as a minibuffer.  */
 403
 404 extern Lisp_Object echo_area_window;
 405
 406 /* Depth in recursive edits.  */
 407
 408 extern int command_loop_level;
 409
 410 /* Depth in minibuffer invocations.  */
 411
 412 extern int minibuf_level;
 413
 414 /* true iff we should redraw the mode lines on the next redisplay.  */
 415
 416 extern int update_mode_lines;
 417
 418 /* Nonzero if BEGV - BEG or Z - ZV of current buffer has changed since
 419    last redisplay that finished.  */
 420
 421 extern int clip_changed;
 422
 423 /* Nonzero if window sizes or contents have changed since last
 424    redisplay that finished */
 425
 426 extern int windows_or_buffers_changed;
 427
 428 /* Number of windows displaying the selected buffer.  Normally this is
 429    1, but it can be more.  */
 430
 431 extern int buffer_shared;
 432
 433 /* If *ROWS or *COLS are too small a size for FRAME, set them to the
 434    minimum allowable size.  */
 435
 436 extern void check_frame_size P_ ((struct frame *frame, int *rows, int *cols));
 437
 438 /* Return a pointer to the glyph W's physical cursor is on.  Value is
 439    null if W's current matrix is invalid, so that no meaningfull glyph
 440    can be returned.  */
 441
 442 struct glyph *get_phys_cursor_glyph P_ ((struct window *w));
 443
 444 #endif /* not WINDOW_H_INCLUDED */