src/xterm.h

   1 /* Definitions and headers for communication with X protocol.
   2    Copyright (C) 1989, 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, Inc., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21 #include <X11/Xlib.h>
  22 #include <X11/cursorfont.h>
  23 #include <X11/Xutil.h>
  24 #include <X11/keysym.h>
  25 #include <X11/Xatom.h>
  26 #include <X11/Xresource.h>
  27
  28 #ifdef USE_X_TOOLKIT
  29 #include <X11/StringDefs.h>
  30 #include <X11/IntrinsicP.h>     /* CoreP.h needs this */
  31 #include <X11/CoreP.h>          /* foul, but we need this to use our own
  32                                    window inside a widget instead of one
  33                                    that Xt creates... */
  34 #include <X11/StringDefs.h>
  35 #endif
  36
  37 /* The class of this X application.  */
  38 #define EMACS_CLASS "Emacs"
  39 \f
  40 /* Bookkeeping to distinguish X versions.  */
  41
  42 /* HAVE_X11R4 is defined if we have the features of X11R4.  It should
  43    be defined when we're using X11R5, since X11R5 has the features of
  44    X11R4.  If, in the future, we find we need more of these flags
  45    (HAVE_X11R5, for example), code should always be written to test
  46    the most recent flag first:
  47
  48       #ifdef HAVE_X11R5
  49         ...
  50       #elif HAVE_X11R4
  51         ...
  52       #elif HAVE_X11
  53         ...
  54       #endif
  55
  56    If you ever find yourself writing a "#ifdef HAVE_FOO" clause that
  57    looks a lot like another one, consider moving the text into a macro
  58    whose definition is configuration-dependent, but whose usage is
  59    universal - like the stuff in systime.h.
  60
  61    It turns out that we can auto-detect whether we're being compiled
  62    with X11R3 or X11R4 by looking for the flag macros for R4 structure
  63    members that R3 doesn't have.  */
  64 #ifdef PBaseSize
  65 /* AIX 3.1's X is somewhere between X11R3 and X11R4.  It has
  66    PBaseSize, but not XWithdrawWindow, XSetWMName, XSetWMNormalHints,
  67    XSetWMIconName.
  68    AIX 3.2 is at least X11R4.  */
  69 #if (!defined AIX) || (defined AIX3_2)
  70 #define HAVE_X11R4
  71 #endif
  72 #endif
  73
  74 #ifdef HAVE_X11R5
  75 /* In case someone has X11R5 on AIX 3.1,
  76    make sure HAVE_X11R4 is defined as well as HAVE_X11R5.  */
  77 #define HAVE_X11R4
  78 #endif
  79
  80 #ifdef HAVE_X11R5
  81 #define HAVE_X_I18N
  82 #include <X11/Xlocale.h>
  83 #endif
  84 \f
  85 #define BLACK_PIX_DEFAULT(f) BlackPixel (FRAME_X_DISPLAY (f), \
  86                                          XScreenNumberOfScreen (FRAME_X_SCREEN (f)))
  87 #define WHITE_PIX_DEFAULT(f) WhitePixel (FRAME_X_DISPLAY (f), \
  88                                          XScreenNumberOfScreen (FRAME_X_SCREEN (f)))
  89
  90 #define FONT_WIDTH(f)   ((f)->max_bounds.width)
  91 #define FONT_HEIGHT(f)  ((f)->ascent + (f)->descent)
  92 #define FONT_BASE(f)    ((f)->ascent)
  93
  94 /* The mask of events that text windows always want to receive.  This
  95    includes mouse movement events, since handling the mouse-font text property
  96    means that we must track mouse motion all the time.  */
  97
  98 #define STANDARD_EVENT_SET      \
  99   (KeyPressMask                 \
 100    | ExposureMask               \
 101    | ButtonPressMask            \
 102    | ButtonReleaseMask          \
 103    | PointerMotionMask          \
 104    | StructureNotifyMask        \
 105    | FocusChangeMask            \
 106    | LeaveWindowMask            \
 107    | EnterWindowMask            \
 108    | VisibilityChangeMask)
 109
 110 /* This checks to make sure we have a display.  */
 111 extern void check_x ();
 112
 113 extern struct frame *x_window_to_frame ();
 114
 115 #ifdef USE_X_TOOLKIT
 116 extern struct frame *x_any_window_to_frame ();
 117 extern struct frame *x_non_menubar_window_to_frame ();
 118 extern struct frame *x_top_window_to_frame ();
 119 #endif
 120
 121 extern Visual *select_visual ();
 122
 123 enum text_cursor_kinds {
 124   filled_box_cursor, hollow_box_cursor, bar_cursor
 125 };
 126
 127 /* Structure recording X pixmap and reference count.
 128    If REFCOUNT is 0 then this record is free to be reused.  */
 129
 130 struct x_bitmap_record
 131 {
 132   Pixmap pixmap;
 133   char *file;
 134   int refcount;
 135   /* Record some info about this pixmap.  */
 136   int height, width, depth;
 137 };
 138 \f
 139 /* For each X display, we have a structure that records
 140    information about it.  */
 141
 142 struct x_display_info
 143 {
 144   /* Chain of all x_display_info structures.  */
 145   struct x_display_info *next;
 146   /* Connection number (normally a file descriptor number).  */
 147   int connection;
 148   /* This says how to access this display in Xlib.  */
 149   Display *display;
 150   /* This is a cons cell of the form (NAME . FONT-LIST-CACHE).
 151      The same cons cell also appears in x_display_name_list.  */
 152   Lisp_Object name_list_element;
 153   /* Number of frames that are on this display.  */
 154   int reference_count;
 155   /* The Screen this connection is connected to.  */
 156   Screen *screen;
 157   /* The Visual being used for this display.  */
 158   Visual *visual;
 159   /* Number of panes on this screen.  */
 160   int n_planes;
 161   /* Dimensions of this screen.  */
 162   int height, width;
 163   /* Mask of things that cause the mouse to be grabbed.  */
 164   int grabbed;
 165   /* Emacs bitmap-id of the default icon bitmap for this frame.
 166      Or -1 if none has been allocated yet.  */
 167   int icon_bitmap_id;
 168   /* The root window of this screen.  */
 169   Window root_window;
 170   /* The cursor to use for vertical scroll bars.  */
 171   Cursor vertical_scroll_bar_cursor;
 172   /* X Resource data base */
 173   XrmDatabase xrdb;
 174
 175   /* A table of all the fonts we have already loaded.  */
 176   struct font_info *font_table;
 177
 178   /* The current capacity of x_font_table.  */
 179   int font_table_size;
 180
 181   /* Reusable Graphics Context for drawing a cursor in a non-default face. */
 182   GC scratch_cursor_gc;
 183
 184   /* These variables describe the range of text currently shown
 185      in its mouse-face, together with the window they apply to.
 186      As long as the mouse stays within this range, we need not
 187      redraw anything on its account.  */
 188   int mouse_face_beg_row, mouse_face_beg_col;
 189   int mouse_face_end_row, mouse_face_end_col;
 190   int mouse_face_past_end;
 191   Lisp_Object mouse_face_window;
 192   int mouse_face_face_id;
 193
 194   /* 1 if a mouse motion event came and we didn't handle it right away because
 195      gc was in progress.  */
 196   int mouse_face_deferred_gc;
 197
 198   /* FRAME and X, Y position of mouse when last checked for
 199      highlighting.  X and Y can be negative or out of range for the frame.  */
 200   struct frame *mouse_face_mouse_frame;
 201   int mouse_face_mouse_x, mouse_face_mouse_y;
 202
 203   /* Nonzero means defer mouse-motion highlighting.  */
 204   int mouse_face_defer;
 205
 206   char *x_id_name;
 207
 208   /* The number of fonts actually stored in x_font_table.
 209      font_table[n] is used and valid iff 0 <= n < n_fonts.
 210      0 <= n_fonts <= font_table_size.  */
 211   int n_fonts;
 212
 213   /* Pointer to bitmap records.  */
 214   struct x_bitmap_record *bitmaps;
 215
 216   /* Allocated size of bitmaps field.  */
 217   int bitmaps_size;
 218
 219   /* Last used bitmap index.  */
 220   int bitmaps_last;
 221
 222   /* Which modifier keys are on which modifier bits?
 223
 224      With each keystroke, X returns eight bits indicating which modifier
 225      keys were held down when the key was pressed.  The interpretation
 226      of the top five modifier bits depends on what keys are attached
 227      to them.  If the Meta_L and Meta_R keysyms are on mod5, then mod5
 228      is the meta bit.
 229
 230      meta_mod_mask is a mask containing the bits used for the meta key.
 231      It may have more than one bit set, if more than one modifier bit
 232      has meta keys on it.  Basically, if EVENT is a KeyPress event,
 233      the meta key is pressed if (EVENT.state & meta_mod_mask) != 0.
 234
 235      shift_lock_mask is LockMask if the XK_Shift_Lock keysym is on the
 236      lock modifier bit, or zero otherwise.  Non-alphabetic keys should
 237      only be affected by the lock modifier bit if XK_Shift_Lock is in
 238      use; XK_Caps_Lock should only affect alphabetic keys.  With this
 239      arrangement, the lock modifier should shift the character if
 240      (EVENT.state & shift_lock_mask) != 0.  */
 241   int meta_mod_mask, shift_lock_mask;
 242
 243   /* These are like meta_mod_mask, but for different modifiers.  */
 244   int alt_mod_mask, super_mod_mask, hyper_mod_mask;
 245
 246   /* Communication with window managers.  */
 247   Atom Xatom_wm_protocols;
 248   /* Kinds of protocol things we may receive.  */
 249   Atom Xatom_wm_take_focus;
 250   Atom Xatom_wm_save_yourself;
 251   Atom Xatom_wm_delete_window;
 252   /* Atom for indicating window state to the window manager.  */
 253   Atom Xatom_wm_change_state;
 254   /* Other WM communication */
 255   Atom Xatom_wm_configure_denied; /* When our config request is denied */
 256   Atom Xatom_wm_window_moved;     /* When the WM moves us.  */
 257   /* EditRes protocol */
 258   Atom Xatom_editres;
 259
 260   /* More atoms, which are selection types.  */
 261   Atom Xatom_CLIPBOARD, Xatom_TIMESTAMP, Xatom_TEXT, Xatom_DELETE,
 262   Xatom_COMPOUND_TEXT,
 263   Xatom_MULTIPLE, Xatom_INCR, Xatom_EMACS_TMP, Xatom_TARGETS, Xatom_NULL,
 264   Xatom_ATOM_PAIR;
 265
 266   /* More atoms for font properties.  The last three are private
 267      properties, see the comments in src/fontset.h.  */
 268   Atom Xatom_PIXEL_SIZE,
 269   Xatom_MULE_BASELINE_OFFSET, Xatom_MULE_RELATIVE_COMPOSE,
 270   Xatom_MULE_DEFAULT_ASCENT;
 271
 272 #ifdef MULTI_KBOARD
 273   struct kboard *kboard;
 274 #endif
 275   int cut_buffers_initialized; /* Whether we're sure they all exist */
 276
 277   /* The frame (if any) which has the X window that has keyboard focus.
 278      Zero if none.  This is examined by Ffocus_frame in xfns.c.  Note
 279      that a mere EnterNotify event can set this; if you need to know the
 280      last frame specified in a FocusIn or FocusOut event, use
 281      x_focus_event_frame.  */
 282   struct frame *x_focus_frame;
 283
 284   /* The last frame mentioned in a FocusIn or FocusOut event.  This is
 285      separate from x_focus_frame, because whether or not LeaveNotify
 286      events cause us to lose focus depends on whether or not we have
 287      received a FocusIn event for it.  */
 288   struct frame *x_focus_event_frame;
 289
 290   /* The frame which currently has the visual highlight, and should get
 291      keyboard input (other sorts of input have the frame encoded in the
 292      event).  It points to the X focus frame's selected window's
 293      frame.  It differs from x_focus_frame when we're using a global
 294      minibuffer.  */
 295   struct frame *x_highlight_frame;
 296
 297   /* The null pixel used for filling a character background with
 298      background color of a gc.  */
 299   Pixmap null_pixel;
 300 };
 301
 302 /* This is a chain of structures for all the X displays currently in use.  */
 303 extern struct x_display_info *x_display_list;
 304
 305 /* This is a list of cons cells, each of the form (NAME . FONT-LIST-CACHE),
 306    one for each element of x_display_list and in the same order.
 307    NAME is the name of the frame.
 308    FONT-LIST-CACHE records previous values returned by x-list-fonts.  */
 309 extern Lisp_Object x_display_name_list;
 310
 311 /* Regexp matching a font name whose width is the same as `PIXEL_SIZE'.  */
 312 extern Lisp_Object Vx_pixel_size_width_font_regexp;
 313
 314 extern struct x_display_info *x_display_info_for_display ();
 315 extern struct x_display_info *x_display_info_for_name ();
 316
 317 extern struct x_display_info *x_term_init ();
 318
 319 extern Lisp_Object x_list_fonts ();
 320 extern struct font_info *x_get_font_info(), *x_load_font (), *x_query_font ();
 321 \f
 322 /* Each X frame object points to its own struct x_output object
 323    in the output_data.x field.  The x_output structure contains
 324    the information that is specific to X windows.  */
 325
 326 struct x_output
 327 {
 328   /* Position of the X window (x and y offsets in root window).  */
 329   int left_pos;
 330   int top_pos;
 331
 332   /* Border width of the X window as known by the X window system.  */
 333   int border_width;
 334
 335   /* Size of the X window in pixels.  */
 336   int pixel_height, pixel_width;
 337
 338   /* Height of menu bar widget, in pixels.
 339      Zero if not using the X toolkit.
 340      When using the toolkit, this value is not meaningful
 341      if the menubar is turned off.  */
 342   int menubar_height;
 343
 344   /* Height of a line, in pixels.  */
 345   int line_height;
 346
 347   /* The tiled border used when the mouse is out of the frame.  */
 348   Pixmap border_tile;
 349
 350   /* Here are the Graphics Contexts for the default font.  */
 351   GC normal_gc;                         /* Normal video */
 352   GC reverse_gc;                        /* Reverse video */
 353   GC cursor_gc;                         /* cursor drawing */
 354
 355   /* Width of the internal border.  This is a line of background color
 356      just inside the window's border.  When the frame is selected,
 357      a highlighting is displayed inside the internal border.  */
 358   int internal_border_width;
 359
 360   /* The X window used for this frame.
 361      May be zero while the frame object is being created
 362      and the X window has not yet been created.  */
 363   Window window_desc;
 364
 365   /* The X window used for the bitmap icon;
 366      or 0 if we don't have a bitmap icon.  */
 367   Window icon_desc;
 368
 369   /* The X window that is the parent of this X window.
 370      Usually this is a window that was made by the window manager,
 371      but it can be the root window, and it can be explicitly specified
 372      (see the explicit_parent field, below).  */
 373   Window parent_desc;
 374
 375 #ifdef USE_X_TOOLKIT
 376   /* The widget of this screen.  This is the window of a "shell" widget.  */
 377   Widget widget;
 378   /* The XmPanedWindows...  */
 379   Widget column_widget;
 380   /* The widget of the edit portion of this screen; the window in
 381      "window_desc" is inside of this.  */
 382   Widget edit_widget;
 383
 384   Widget menubar_widget;
 385 #endif
 386
 387   /* If >=0, a bitmap index.  The indicated bitmap is used for the
 388      icon. */
 389   int icon_bitmap;
 390
 391   /* Default ASCII font of this frame.  */
 392   XFontStruct *font;
 393
 394   /* The baseline position of the default ASCII font.  */
 395   int font_baseline;
 396
 397   /* If a fontset is specified for this frame instead of font, this
 398      value contains an ID of the fontset, else -1.  */
 399   int fontset;
 400
 401   /* Pixel values used for various purposes.
 402      border_pixel may be -1 meaning use a gray tile.  */
 403   unsigned long background_pixel;
 404   unsigned long foreground_pixel;
 405   unsigned long cursor_pixel;
 406   unsigned long border_pixel;
 407   unsigned long mouse_pixel;
 408   unsigned long cursor_foreground_pixel;
 409
 410   /* Descriptor for the cursor in use for this window.  */
 411   Cursor text_cursor;
 412   Cursor nontext_cursor;
 413   Cursor modeline_cursor;
 414   Cursor cross_cursor;
 415
 416   /* Flag to set when the X window needs to be completely repainted.  */
 417   int needs_exposure;
 418
 419   /* What kind of text cursor is drawn in this window right now?
 420      (If there is no cursor (phys_cursor_x < 0), then this means nothing.)  */
 421   enum text_cursor_kinds current_cursor;
 422
 423   /* What kind of text cursor should we draw in the future?
 424      This should always be filled_box_cursor or bar_cursor.  */
 425   enum text_cursor_kinds desired_cursor;
 426
 427   /* Width of bar cursor (if we are using that).  */
 428   int cursor_width;
 429
 430   /* These are the current window manager hints.  It seems that
 431      XSetWMHints, when presented with an unset bit in the `flags'
 432      member of the hints structure, does not leave the corresponding
 433      attribute unchanged; rather, it resets that attribute to its
 434      default value.  For example, unless you set the `icon_pixmap'
 435      field and the `IconPixmapHint' bit, XSetWMHints will forget what
 436      your icon pixmap was.  This is rather troublesome, since some of
 437      the members (for example, `input' and `icon_pixmap') want to stay
 438      the same throughout the execution of Emacs.  So, we keep this
 439      structure around, just leaving values in it and adding new bits
 440      to the mask as we go.  */
 441   XWMHints wm_hints;
 442
 443   /* The size of the extra width currently allotted for vertical
 444      scroll bars, in pixels.  */
 445   int vertical_scroll_bar_extra;
 446
 447   /* Table of parameter faces for this frame.  Any X resources (pixel
 448      values, fonts) referred to here have been allocated explicitly
 449      for this face, and should be freed if we change the face.  */
 450   struct face **param_faces;
 451   int n_param_faces;
 452
 453   /* Table of computed faces for this frame.  These are the faces
 454      whose indexes go into the upper bits of a glyph, computed by
 455      combining the parameter faces specified by overlays, text
 456      properties, and what have you.  The X resources mentioned here
 457      are all shared with parameter faces.  */
 458   struct face **computed_faces;
 459   int n_computed_faces;         /* How many are valid */
 460   int size_computed_faces;      /* How many are allocated */
 461
 462   /* This is the gravity value for the specified window position.  */
 463   int win_gravity;
 464
 465   /* The geometry flags for this window.  */
 466   int size_hint_flags;
 467
 468   /* This is the Emacs structure for the X display this frame is on.  */
 469   struct x_display_info *display_info;
 470
 471   /* This is a button event that wants to activate the menubar.
 472      We save it here until the command loop gets to think about it.  */
 473   XEvent *saved_menu_event;
 474
 475   /* This is the widget id used for this frame's menubar in lwlib.  */
 476 #ifdef USE_X_TOOLKIT
 477   int id;
 478 #endif
 479
 480   /* Nonzero means our parent is another application's window
 481      and was explicitly specified.  */
 482   char explicit_parent;
 483
 484   /* Nonzero means tried already to make this frame visible.  */
 485   char asked_for_visible;
 486
 487   /* Nonzero if this frame was ever previously visible.  */
 488   char has_been_visible;
 489
 490 #ifdef HAVE_X_I18N
 491   /* Input method. */
 492   XIM xim;
 493   /* Input context (currently, this means Compose key handler setup).  */
 494   XIC xic;
 495 #endif
 496 };
 497
 498 /* Get at the computed faces of an X window frame.  */
 499 #define FRAME_PARAM_FACES(f) ((f)->output_data.x->param_faces)
 500 #define FRAME_N_PARAM_FACES(f) ((f)->output_data.x->n_param_faces)
 501 #define FRAME_DEFAULT_PARAM_FACE(f) (FRAME_PARAM_FACES (f)[0])
 502 #define FRAME_MODE_LINE_PARAM_FACE(f) (FRAME_PARAM_FACES (f)[1])
 503
 504 #define FRAME_COMPUTED_FACES(f) ((f)->output_data.x->computed_faces)
 505 #define FRAME_N_COMPUTED_FACES(f) ((f)->output_data.x->n_computed_faces)
 506 #define FRAME_SIZE_COMPUTED_FACES(f) ((f)->output_data.x->size_computed_faces)
 507 #define FRAME_DEFAULT_FACE(f) ((f)->output_data.x->computed_faces[0])
 508 #define FRAME_MODE_LINE_FACE(f) ((f)->output_data.x->computed_faces[1])
 509
 510 /* Return the window associated with the frame F.  */
 511 #define FRAME_X_WINDOW(f) ((f)->output_data.x->window_desc)
 512
 513 #define FRAME_FOREGROUND_PIXEL(f) ((f)->output_data.x->foreground_pixel)
 514 #define FRAME_BACKGROUND_PIXEL(f) ((f)->output_data.x->background_pixel)
 515 #define FRAME_FONT(f) ((f)->output_data.x->font)
 516 #define FRAME_FONTSET(f) ((f)->output_data.x->fontset)
 517 #define FRAME_INTERNAL_BORDER_WIDTH(f) ((f)->output_data.x->internal_border_width)
 518 #define FRAME_LINE_HEIGHT(f) ((f)->output_data.x->line_height)
 519
 520 /* This gives the x_display_info structure for the display F is on.  */
 521 #define FRAME_X_DISPLAY_INFO(f) ((f)->output_data.x->display_info)
 522
 523 /* This is the `Display *' which frame F is on.  */
 524 #define FRAME_X_DISPLAY(f) (FRAME_X_DISPLAY_INFO (f)->display)
 525
 526 /* This is the `Screen *' which frame F is on.  */
 527 #define FRAME_X_SCREEN(f) (FRAME_X_DISPLAY_INFO (f)->screen)
 528
 529 /* This is the 'font_info *' which frame F has.  */
 530 #define FRAME_X_FONT_TABLE(f) (FRAME_X_DISPLAY_INFO (f)->font_table)
 531
 532 /* These two really ought to be called FRAME_PIXEL_{WIDTH,HEIGHT}.  */
 533 #define PIXEL_WIDTH(f) ((f)->output_data.x->pixel_width)
 534 #define PIXEL_HEIGHT(f) ((f)->output_data.x->pixel_height)
 535
 536 #define FRAME_DESIRED_CURSOR(f) ((f)->output_data.x->desired_cursor)
 537
 538 #define FRAME_XIM(f) ((f)->output_data.x->xim)
 539 #define FRAME_XIC(f) ((f)->output_data.x->xic)
 540 \f
 541 /* X-specific scroll bar stuff.  */
 542
 543 /* We represent scroll bars as lisp vectors.  This allows us to place
 544    references to them in windows without worrying about whether we'll
 545    end up with windows referring to dead scroll bars; the garbage
 546    collector will free it when its time comes.
 547
 548    We use struct scroll_bar as a template for accessing fields of the
 549    vector.  */
 550
 551 struct scroll_bar {
 552
 553   /* These fields are shared by all vectors.  */
 554   EMACS_INT size_from_Lisp_Vector_struct;
 555   struct Lisp_Vector *next_from_Lisp_Vector_struct;
 556
 557   /* The window we're a scroll bar for.  */
 558   Lisp_Object window;
 559
 560   /* The next and previous in the chain of scroll bars in this frame.  */
 561   Lisp_Object next, prev;
 562
 563   /* The X window representing this scroll bar.  Since this is a full
 564      32-bit quantity, we store it split into two 32-bit values.  */
 565   Lisp_Object x_window_low, x_window_high;
 566
 567   /* The position and size of the scroll bar in pixels, relative to the
 568      frame.  */
 569   Lisp_Object top, left, width, height;
 570
 571   /* The starting and ending positions of the handle, relative to the
 572      handle area (i.e. zero is the top position, not
 573      SCROLL_BAR_TOP_BORDER).  If they're equal, that means the handle
 574      hasn't been drawn yet.
 575
 576      These are not actually the locations where the beginning and end
 577      are drawn; in order to keep handles from becoming invisible when
 578      editing large files, we establish a minimum height by always
 579      drawing handle bottoms VERTICAL_SCROLL_BAR_MIN_HANDLE pixels below
 580      where they would be normally; the bottom and top are in a
 581      different co-ordinate system.  */
 582   Lisp_Object start, end;
 583
 584   /* If the scroll bar handle is currently being dragged by the user,
 585      this is the number of pixels from the top of the handle to the
 586      place where the user grabbed it.  If the handle isn't currently
 587      being dragged, this is Qnil.  */
 588   Lisp_Object dragging;
 589 };
 590
 591 /* The number of elements a vector holding a struct scroll_bar needs.  */
 592 #define SCROLL_BAR_VEC_SIZE                                     \
 593   ((sizeof (struct scroll_bar)                                  \
 594     - sizeof (EMACS_INT) - sizeof (struct Lisp_Vector *))       \
 595    / sizeof (Lisp_Object))
 596
 597 /* Turning a lisp vector value into a pointer to a struct scroll_bar.  */
 598 #define XSCROLL_BAR(vec) ((struct scroll_bar *) XVECTOR (vec))
 599
 600
 601 /* Building a 32-bit C integer from two 16-bit lisp integers.  */
 602 #define SCROLL_BAR_PACK(low, high) (XINT (high) << 16 | XINT (low))
 603
 604 /* Setting two lisp integers to the low and high words of a 32-bit C int.  */
 605 #define SCROLL_BAR_UNPACK(low, high, int32) \
 606   (XSETINT ((low),   (int32)        & 0xffff), \
 607    XSETINT ((high), ((int32) >> 16) & 0xffff))
 608
 609
 610 /* Extract the X window id of the scroll bar from a struct scroll_bar.  */
 611 #define SCROLL_BAR_X_WINDOW(ptr) \
 612   ((Window) SCROLL_BAR_PACK ((ptr)->x_window_low, (ptr)->x_window_high))
 613
 614 /* Store a window id in a struct scroll_bar.  */
 615 #define SET_SCROLL_BAR_X_WINDOW(ptr, id) \
 616   (SCROLL_BAR_UNPACK ((ptr)->x_window_low, (ptr)->x_window_high, (int) id))
 617
 618
 619 /* Return the outside pixel height for a vertical scroll bar HEIGHT
 620    rows high on frame F.  */
 621 #define VERTICAL_SCROLL_BAR_PIXEL_HEIGHT(f, height) \
 622   ((height) * (f)->output_data.x->line_height)
 623
 624 /* Return the inside width of a vertical scroll bar, given the outside
 625    width.  */
 626 #define VERTICAL_SCROLL_BAR_INSIDE_WIDTH(f, width) \
 627   ((width) \
 628    - VERTICAL_SCROLL_BAR_LEFT_BORDER \
 629    - VERTICAL_SCROLL_BAR_RIGHT_BORDER \
 630    - VERTICAL_SCROLL_BAR_WIDTH_TRIM * 2)
 631
 632 /* Return the length of the rectangle within which the top of the
 633    handle must stay.  This isn't equivalent to the inside height,
 634    because the scroll bar handle has a minimum height.
 635
 636    This is the real range of motion for the scroll bar, so when we're
 637    scaling buffer positions to scroll bar positions, we use this, not
 638    VERTICAL_SCROLL_BAR_INSIDE_HEIGHT.  */
 639 #define VERTICAL_SCROLL_BAR_TOP_RANGE(f, height) \
 640   (VERTICAL_SCROLL_BAR_INSIDE_HEIGHT (f, height) - VERTICAL_SCROLL_BAR_MIN_HANDLE)
 641
 642 /* Return the inside height of vertical scroll bar, given the outside
 643    height.  See VERTICAL_SCROLL_BAR_TOP_RANGE too.  */
 644 #define VERTICAL_SCROLL_BAR_INSIDE_HEIGHT(f, height) \
 645   ((height) - VERTICAL_SCROLL_BAR_TOP_BORDER - VERTICAL_SCROLL_BAR_BOTTOM_BORDER)
 646
 647
 648 /* Border widths for scroll bars.
 649
 650    Scroll bar windows don't have any X borders; their border width is
 651    set to zero, and we redraw borders ourselves.  This makes the code
 652    a bit cleaner, since we don't have to convert between outside width
 653    (used when relating to the rest of the screen) and inside width
 654    (used when sizing and drawing the scroll bar window itself).
 655
 656    The handle moves up and down/back and forth in a rectangle inset
 657    from the edges of the scroll bar.  These are widths by which we
 658    inset the handle boundaries from the scroll bar edges.  */
 659 #define VERTICAL_SCROLL_BAR_LEFT_BORDER (2)
 660 #define VERTICAL_SCROLL_BAR_RIGHT_BORDER (2)
 661 #define VERTICAL_SCROLL_BAR_TOP_BORDER (2)
 662 #define VERTICAL_SCROLL_BAR_BOTTOM_BORDER (2)
 663
 664 /* Minimum lengths for scroll bar handles, in pixels.  */
 665 #define VERTICAL_SCROLL_BAR_MIN_HANDLE (5)
 666
 667 /* Trimming off a few pixels from each side prevents
 668    text from glomming up against the scroll bar */
 669 #define VERTICAL_SCROLL_BAR_WIDTH_TRIM (2)
 670
 671 \f
 672 /* Manipulating pixel sizes and character sizes.
 673    Knowledge of which factors affect the overall size of the window should
 674    be hidden in these macros, if that's possible.
 675
 676    Return the upper/left pixel position of the character cell on frame F
 677    at ROW/COL.  */
 678 #define CHAR_TO_PIXEL_ROW(f, row) \
 679   ((f)->output_data.x->internal_border_width \
 680    + (row) * (f)->output_data.x->line_height)
 681 #define CHAR_TO_PIXEL_COL(f, col) \
 682   ((f)->output_data.x->internal_border_width \
 683    + (col) * FONT_WIDTH ((f)->output_data.x->font))
 684
 685 /* Return the pixel width/height of frame F if it has
 686    WIDTH columns/HEIGHT rows.  */
 687 #define CHAR_TO_PIXEL_WIDTH(f, width) \
 688   (CHAR_TO_PIXEL_COL (f, width) \
 689    + (f)->output_data.x->vertical_scroll_bar_extra \
 690    + (f)->output_data.x->internal_border_width)
 691 #define CHAR_TO_PIXEL_HEIGHT(f, height) \
 692   (CHAR_TO_PIXEL_ROW (f, height) \
 693    + (f)->output_data.x->internal_border_width)
 694
 695
 696 /* Return the row/column (zero-based) of the character cell containing
 697    the pixel on FRAME at ROW/COL.  */
 698 #define PIXEL_TO_CHAR_ROW(f, row) \
 699   (((row) - (f)->output_data.x->internal_border_width) \
 700    / (f)->output_data.x->line_height)
 701 #define PIXEL_TO_CHAR_COL(f, col) \
 702   (((col) - (f)->output_data.x->internal_border_width) \
 703    / FONT_WIDTH ((f)->output_data.x->font))
 704
 705 /* How many columns/rows of text can we fit in WIDTH/HEIGHT pixels on
 706    frame F?  */
 707 #define PIXEL_TO_CHAR_WIDTH(f, width) \
 708   (PIXEL_TO_CHAR_COL (f, ((width) \
 709                           - (f)->output_data.x->internal_border_width \
 710                           - (f)->output_data.x->vertical_scroll_bar_extra)))
 711 #define PIXEL_TO_CHAR_HEIGHT(f, height) \
 712   (PIXEL_TO_CHAR_ROW (f, ((height) \
 713                           - (f)->output_data.x->internal_border_width)))
 714 \f
 715 /* If a struct input_event has a kind which is selection_request_event
 716    or selection_clear_event, then its contents are really described
 717    by this structure.  */
 718
 719 /* For an event of kind selection_request_event,
 720    this structure really describes the contents.
 721    **Don't make this struct longer!**
 722    If it overlaps the frame_or_window field of struct input_event,
 723    that will cause GC to crash.  */
 724 struct selection_input_event
 725 {
 726   int kind;
 727   Display *display;
 728   /* We spell it with an "o" here because X does.  */
 729   Window requestor;
 730   Atom selection, target, property;
 731   Time time;
 732 };
 733
 734 #define SELECTION_EVENT_DISPLAY(eventp) \
 735   (((struct selection_input_event *) (eventp))->display)
 736 /* We spell it with an "o" here because X does.  */
 737 #define SELECTION_EVENT_REQUESTOR(eventp)       \
 738   (((struct selection_input_event *) (eventp))->requestor)
 739 #define SELECTION_EVENT_SELECTION(eventp)       \
 740   (((struct selection_input_event *) (eventp))->selection)
 741 #define SELECTION_EVENT_TARGET(eventp)  \
 742   (((struct selection_input_event *) (eventp))->target)
 743 #define SELECTION_EVENT_PROPERTY(eventp)        \
 744   (((struct selection_input_event *) (eventp))->property)
 745 #define SELECTION_EVENT_TIME(eventp)    \
 746   (((struct selection_input_event *) (eventp))->time)
 747
 748 \f
 749 /* Interface to the face code functions.  */
 750
 751 /* Create the first two computed faces for a frame -- the ones that
 752    have GC's.  */
 753 extern void init_frame_faces (/* FRAME_PTR */);
 754
 755 /* Free the resources for the faces associated with a frame.  */
 756 extern void free_frame_faces (/* FRAME_PTR */);
 757
 758 /* Given a computed face, find or make an equivalent display face
 759    in face_vector, and return a pointer to it.  */
 760 extern struct face *intern_face (/* FRAME_PTR, struct face * */);
 761
 762 /* Given a frame and a face name, return the face's ID number, or
 763    zero if it isn't a recognized face name.  */
 764 extern int face_name_id_number (/* FRAME_PTR, Lisp_Object */);
 765
 766 /* Return non-zero if FONT1 and FONT2 have the same size bounding box.
 767    We assume that they're both character-cell fonts.  */
 768 extern int same_size_fonts (/* XFontStruct *, XFontStruct * */);
 769
 770 /* Recompute the GC's for the default and modeline faces.
 771    We call this after changing frame parameters on which those GC's
 772    depend.  */
 773 extern void recompute_basic_faces (/* FRAME_PTR */);
 774
 775 /* Return the face ID associated with a buffer position POS.  Store
 776    into *ENDPTR the next position at which a different face is
 777    needed.  This does not take account of glyphs that specify their
 778    own face codes.  F is the frame in use for display, and W is a
 779    window displaying the current buffer.
 780
 781    REGION_BEG, REGION_END delimit the region, so it can be highlighted.  */
 782 extern int compute_char_face (/* FRAME_PTR frame,
 783                                  struct window *w,
 784                                  int pos,
 785                                  int region_beg, int region_end,
 786                                  int *endptr */);
 787 /* Return the face ID to use to display a special glyph which selects
 788    FACE_CODE as the face ID, assuming that ordinarily the face would
 789    be BASIC_FACE.  F is the frame.  */
 790 extern int compute_glyph_face (/* FRAME_PTR, int */);