src/termhooks.h

   1 /* Parameters and display hooks for terminal devices.
   2
   3 Copyright (C) 1985-1986, 1993-1994, 2001-2017 Free Software Foundation,
   4 Inc.
   5
   6 This file is part of GNU Emacs.
   7
   8 GNU Emacs is free software: you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation, either version 3 of the License, or (at
  11 your option) any later version.
  12
  13 GNU Emacs is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
  20
  21 #ifndef EMACS_TERMHOOKS_H
  22 #define EMACS_TERMHOOKS_H
  23
  24 /* Miscellanea.   */
  25
  26 #include "lisp.h"
  27 #include "systime.h" /* for Time */
  28
  29 struct glyph;
  30
  31 INLINE_HEADER_BEGIN
  32
  33 enum scroll_bar_part {
  34   scroll_bar_nowhere,
  35   scroll_bar_above_handle,
  36   scroll_bar_handle,
  37   scroll_bar_below_handle,
  38   scroll_bar_up_arrow,
  39   scroll_bar_down_arrow,
  40   scroll_bar_to_top,
  41   scroll_bar_to_bottom,
  42   scroll_bar_end_scroll,
  43   scroll_bar_move_ratio,
  44   scroll_bar_before_handle,
  45   scroll_bar_horizontal_handle,
  46   scroll_bar_after_handle,
  47   scroll_bar_left_arrow,
  48   scroll_bar_right_arrow,
  49   scroll_bar_to_leftmost,
  50   scroll_bar_to_rightmost
  51 };
  52
  53 /* Output method of a terminal (and frames on this terminal, respectively).  */
  54
  55 enum output_method
  56 {
  57   output_initial,
  58   output_termcap,
  59   output_x_window,
  60   output_msdos_raw,
  61   output_w32,
  62   output_ns
  63 };
  64
  65 /* Input queue declarations and hooks.  */
  66
  67 enum event_kind
  68 {
  69   NO_EVENT,                     /* nothing happened.  This should never
  70                                    actually appear in the event queue.  */
  71
  72   ASCII_KEYSTROKE_EVENT,        /* The ASCII code is in .code, perhaps
  73                                    with modifiers applied.
  74                                    .modifiers holds the state of the
  75                                    modifier keys.
  76                                    .frame_or_window is the frame in
  77                                    which the key was typed.
  78                                    .timestamp gives a timestamp (in
  79                                    milliseconds) for the keystroke.  */
  80   MULTIBYTE_CHAR_KEYSTROKE_EVENT,       /* The multibyte char code is in .code,
  81                                    perhaps with modifiers applied.
  82                                    The others are the same as
  83                                    ASCII_KEYSTROKE_EVENT.  */
  84   NON_ASCII_KEYSTROKE_EVENT,    /* .code is a number identifying the
  85                                    function key.  A code N represents
  86                                    a key whose name is
  87                                    function_key_names[N]; function_key_names
  88                                    is a table in keyboard.c to which you
  89                                    should feel free to add missing keys.
  90                                    .modifiers holds the state of the
  91                                    modifier keys.
  92                                    .frame_or_window is the frame in
  93                                    which the key was typed.
  94                                    .timestamp gives a timestamp (in
  95                                    milliseconds) for the keystroke.  */
  96   TIMER_EVENT,                  /* A timer fired.  */
  97   MOUSE_CLICK_EVENT,            /* The button number is in .code; it must
  98                                    be >= 0 and < NUM_MOUSE_BUTTONS, defined
  99                                    below.
 100                                    .modifiers holds the state of the
 101                                    modifier keys.
 102                                    .x and .y give the mouse position,
 103                                    in characters, within the window.
 104                                    .frame_or_window gives the frame
 105                                    the mouse click occurred in.
 106                                    .timestamp gives a timestamp (in
 107                                    milliseconds) for the click.  */
 108   WHEEL_EVENT,                  /* A wheel event is generated by a
 109                                    wheel on a mouse (e.g., MS
 110                                    Intellimouse).
 111                                    .modifiers holds the rotate
 112                                    direction (up or down), and the
 113                                    state of the modifier keys.
 114                                    .x and .y give the mouse position,
 115                                    in characters, within the window.
 116                                    .frame_or_window gives the frame
 117                                    the wheel event occurred in.
 118                                    .timestamp gives a timestamp (in
 119                                    milliseconds) for the event.
 120                                    .arg may contain the number of
 121                                    lines to scroll.  */
 122   HORIZ_WHEEL_EVENT,            /* A wheel event generated by a second
 123                                    horizontal wheel that is present on some
 124                                    mice. See WHEEL_EVENT.  */
 125 #ifdef HAVE_NTGUI
 126   LANGUAGE_CHANGE_EVENT,        /* A LANGUAGE_CHANGE_EVENT is
 127                                    generated when HAVE_NTGUI or on Mac OS
 128                                    when the keyboard layout or input
 129                                    language is changed by the
 130                                    user.  */
 131 #endif
 132   SCROLL_BAR_CLICK_EVENT,       /* .code gives the number of the mouse button
 133                                    that was clicked.
 134                                    .modifiers holds the state of the modifier
 135                                    keys.
 136                                    .part is a lisp symbol indicating which
 137                                    part of the scroll bar got clicked.
 138                                    .x gives the distance from the start of the
 139                                    scroll bar of the click; .y gives the total
 140                                    length of the scroll bar.
 141                                    .frame_or_window gives the window
 142                                    whose scroll bar was clicked in.
 143                                    .timestamp gives a timestamp (in
 144                                    milliseconds) for the click.  */
 145   HORIZONTAL_SCROLL_BAR_CLICK_EVENT,    /* .code gives the number of the mouse button
 146                                    that was clicked.
 147                                    .modifiers holds the state of the modifier
 148                                    keys.
 149                                    .part is a lisp symbol indicating which
 150                                    part of the scroll bar got clicked.
 151                                    .x gives the distance from the start of the
 152                                    scroll bar of the click; .y gives the total
 153                                    length of the scroll bar.
 154                                    .frame_or_window gives the window
 155                                    whose scroll bar was clicked in.
 156                                    .timestamp gives a timestamp (in
 157                                    milliseconds) for the click.  */
 158   SELECTION_REQUEST_EVENT,      /* Another X client wants a selection from us.
 159                                    See `struct selection_input_event'.  */
 160   SELECTION_CLEAR_EVENT,        /* Another X client cleared our selection.  */
 161   BUFFER_SWITCH_EVENT,          /* A process filter has switched buffers.  */
 162   DELETE_WINDOW_EVENT,          /* An X client said "delete this window".  */
 163 #ifdef HAVE_NTGUI
 164   END_SESSION_EVENT,            /* The user is logging out or shutting down.  */
 165 #endif
 166   MENU_BAR_EVENT,               /* An event generated by the menu bar.
 167                                    The frame_or_window field's cdr holds the
 168                                    Lisp-level event value.
 169                                    (Only the toolkit version uses these.)  */
 170   ICONIFY_EVENT,                /* An X client iconified this window.  */
 171   DEICONIFY_EVENT,              /* An X client deiconified this window.  */
 172   MENU_BAR_ACTIVATE_EVENT,      /* A button press in the menu bar
 173                                    (toolkit version only).  */
 174   DRAG_N_DROP_EVENT,            /* A drag-n-drop event is generated when
 175                                    files selected outside of Emacs are dropped
 176                                    onto an Emacs window.
 177                                    .modifiers holds the state of the
 178                                    modifier keys.
 179                                    .x and .y give the mouse position,
 180                                    in characters, within the window.
 181                                    .frame_or_window is the frame in
 182                                    which the drop was made.
 183                                    .arg is a platform-dependent
 184                                    representation of the dropped items.
 185                                    .timestamp gives a timestamp (in
 186                                    milliseconds) for the click.  */
 187   USER_SIGNAL_EVENT,            /* A user signal.
 188                                    code is a number identifying it,
 189                                    index into lispy_user_signals.  */
 190
 191   /* Help events.  Member `frame_or_window' of the input_event is the
 192      frame on which the event occurred, and member `arg' contains
 193      the help to show.  */
 194   HELP_EVENT,
 195
 196   /* An event from a tool-bar.  Member `arg' of the input event
 197      contains the tool-bar item selected.  If `frame_or_window'
 198      and `arg' are equal, this is a prefix event.  */
 199   TOOL_BAR_EVENT,
 200
 201   /* Queued from XTread_socket on FocusIn events.  Translated into
 202      `switch-frame' events in kbd_buffer_get_event, if necessary.  */
 203   FOCUS_IN_EVENT,
 204
 205   FOCUS_OUT_EVENT,
 206
 207   /* Generated when a frame is moved.  */
 208   MOVE_FRAME_EVENT,
 209
 210   /* Generated when mouse moves over window not currently selected.  */
 211   SELECT_WINDOW_EVENT,
 212
 213   /* Queued from XTread_socket when session manager sends
 214      save yourself before shutdown. */
 215   SAVE_SESSION_EVENT
 216
 217 #ifdef HAVE_GPM
 218   , GPM_CLICK_EVENT
 219 #endif
 220
 221 #ifdef HAVE_DBUS
 222   , DBUS_EVENT
 223 #endif
 224
 225   , CONFIG_CHANGED_EVENT
 226
 227 #ifdef HAVE_NTGUI
 228   /* Generated when an APPCOMMAND event is received, in response to
 229      Multimedia or Internet buttons on some keyboards.
 230      Such keys are available as normal function keys on X through the
 231      Xkeyboard extension.
 232      On Windows, some of them get mapped to normal function key events,
 233      but others need to be handled by APPCOMMAND. Handling them all as
 234      APPCOMMAND events means they can be disabled
 235      (w32-pass-multimedia-buttons-to-system), important on Windows since
 236      the system never sees these keys if Emacs claims to handle them.
 237      On X, the window manager seems to grab the keys it wants
 238      first, so this is not a problem there.  */
 239   , MULTIMEDIA_KEY_EVENT
 240 #endif
 241
 242 #ifdef HAVE_NS
 243   /* Generated when native multi-keystroke input method is used to modify
 244      tentative or indicative text display. */
 245   , NS_TEXT_EVENT
 246   /* Non-key system events (e.g. application menu events) */
 247   , NS_NONKEY_EVENT
 248 #endif
 249
 250 #ifdef HAVE_XWIDGETS
 251   /* events generated by xwidgets*/
 252    , XWIDGET_EVENT
 253 #endif
 254
 255 #ifdef USE_FILE_NOTIFY
 256   /* File or directory was changed.  */
 257   , FILE_NOTIFY_EVENT
 258 #endif
 259
 260 };
 261
 262 /* Bit width of an enum event_kind tag at the start of structs and unions.  */
 263 enum { EVENT_KIND_WIDTH = 16 };
 264
 265 /* If a struct input_event has a kind which is SELECTION_REQUEST_EVENT
 266    or SELECTION_CLEAR_EVENT, then its contents are really described
 267    by `struct selection_input_event'; see xterm.h.  */
 268
 269 /* The keyboard input buffer is an array of these structures.  Each one
 270    represents some sort of input event - a keystroke, a mouse click, or
 271    a window system event.  These get turned into their lispy forms when
 272    they are removed from the event queue.  */
 273
 274 struct input_event
 275 {
 276   /* What kind of event was this?  */
 277   ENUM_BF (event_kind) kind : EVENT_KIND_WIDTH;
 278
 279   /* Used in scroll back click events.  */
 280   ENUM_BF (scroll_bar_part) part : 16;
 281
 282   /* For an ASCII_KEYSTROKE_EVENT and MULTIBYTE_CHAR_KEYSTROKE_EVENT,
 283      this is the character.
 284      For a NON_ASCII_KEYSTROKE_EVENT, this is the keysym code.
 285      For a mouse event, this is the button number.  */
 286   unsigned code;
 287
 288   /* See enum below for interpretation.  */
 289   unsigned modifiers;
 290
 291   /* One would prefer C integers, but HELP_EVENT uses these to
 292      record frame or window object and a help form, respectively.  */
 293   Lisp_Object x, y;
 294
 295   /* Usually a time as reported by window system-specific event loop.
 296      For a HELP_EVENT, this is the position within the object (stored
 297      in ARG below) where the help was found.  */
 298   Time timestamp;
 299
 300   /* This field is copied into a vector while the event is in
 301      the queue, so that garbage collections won't kill it.  */
 302   Lisp_Object frame_or_window;
 303
 304   /* This additional argument is used in attempt to avoid extra consing
 305      when building events.  Unfortunately some events have to pass much
 306      more data than it's reasonable to pack directly into this structure.  */
 307   Lisp_Object arg;
 308 };
 309
 310 #define EVENT_INIT(event) memset (&(event), 0, sizeof (struct input_event))
 311
 312 /* Bits in the modifiers member of the input_event structure.
 313    Note that reorder_modifiers assumes that the bits are in canonical
 314    order.
 315
 316    The modifiers applied to mouse clicks are rather ornate.  The
 317    window-system-specific code should store mouse clicks with
 318    up_modifier or down_modifier set.  Having an explicit down modifier
 319    simplifies some of window-system-independent code; without it, the
 320    code would have to recognize down events by checking if the event
 321    is a mouse click lacking the click and drag modifiers.
 322
 323    The window-system independent code turns all up_modifier events
 324    bits into drag_modifier, click_modifier, double_modifier, or
 325    triple_modifier events.  The click_modifier has no written
 326    representation in the names of the symbols used as event heads,
 327    but it does appear in the Qevent_symbol_components property of the
 328    event heads.  */
 329 enum {
 330   up_modifier   =   1,          /* Only used on mouse buttons - always
 331                                    turned into a click or a drag modifier
 332                                    before lisp code sees the event.  */
 333   down_modifier =   2,          /* Only used on mouse buttons.  */
 334   drag_modifier =   4,          /* This is never used in the event
 335                                    queue; it's only used internally by
 336                                    the window-system-independent code.  */
 337   click_modifier=   8,          /* See drag_modifier.  */
 338   double_modifier= 16,          /* See drag_modifier.  */
 339   triple_modifier= 32,          /* See drag_modifier.  */
 340
 341   /* The next four modifier bits are used also in keyboard events at
 342      the Lisp level.
 343
 344      It's probably not the greatest idea to use the 2^28 bit for any
 345      modifier.  It may or may not be the sign bit, depending on
 346      FIXNUM_BITS, so using it to represent a modifier key means that
 347      characters thus modified have different integer equivalents
 348      depending on the architecture they're running on.  Oh, and
 349      applying XINT to a character whose 2^28 bit is set might sign-extend
 350      it, so you get a bunch of bits in the mask you didn't want.
 351
 352      The CHAR_ macros are defined in lisp.h.  */
 353   alt_modifier  =  CHAR_ALT,    /* Under X, the XK_Alt_[LR] keysyms.  */
 354   super_modifier=  CHAR_SUPER,  /* Under X, the XK_Super_[LR] keysyms.  */
 355   hyper_modifier=  CHAR_HYPER,  /* Under X, the XK_Hyper_[LR] keysyms.  */
 356   shift_modifier=  CHAR_SHIFT,
 357   ctrl_modifier =  CHAR_CTL,
 358   meta_modifier =  CHAR_META    /* Under X, the XK_Meta_[LR] keysyms.  */
 359 };
 360
 361 #ifdef HAVE_GPM
 362 #include <gpm.h>
 363 extern int handle_one_term_event (struct tty_display_info *, Gpm_Event *, struct input_event *);
 364 #ifndef HAVE_WINDOW_SYSTEM
 365 extern void term_mouse_moveto (int, int);
 366 #endif
 367
 368 /* The device for which we have enabled gpm support.  */
 369 extern struct tty_display_info *gpm_tty;
 370 #endif
 371
 372 /* Terminal-local parameters. */
 373 struct terminal
 374 {
 375   /* This is for Lisp; the terminal code does not refer to it.  */
 376   struct vectorlike_header header;
 377
 378   /* Parameter alist of this terminal.  */
 379   Lisp_Object param_alist;
 380
 381   /* List of charsets supported by the terminal.  It is set by
 382      Fset_terminal_coding_system_internal along with
 383      the member terminal_coding.  */
 384   Lisp_Object charset_list;
 385
 386   /* This is an association list containing the X selections that
 387      Emacs might own on this terminal.  Each element has the form
 388        (SELECTION-NAME SELECTION-VALUE SELECTION-TIMESTAMP FRAME)
 389      SELECTION-NAME is a lisp symbol, whose name is the name of an X Atom.
 390      SELECTION-VALUE is the value that emacs owns for that selection.
 391       It may be any kind of Lisp object.
 392      SELECTION-TIMESTAMP is the time at which emacs began owning this
 393       selection, as a cons of two 16-bit numbers (making a 32 bit
 394       time.)
 395      FRAME is the frame for which we made the selection.  If there is
 396       an entry in this alist, then it can be assumed that Emacs owns
 397       that selection.
 398      The only (eq) parts of this list that are visible from Lisp are
 399     the selection-values.  */
 400   Lisp_Object Vselection_alist;
 401
 402   /* If a char-table, this maps characters to terminal glyph codes.
 403      If t, the mapping is not available.  If nil, it is not known
 404      whether the mapping is available.  */
 405   Lisp_Object glyph_code_table;
 406
 407   /* All fields before `next_terminal' should be Lisp_Object and are traced
 408      by the GC.  All fields afterwards are ignored by the GC.  */
 409
 410   /* Chain of all terminal devices. */
 411   struct terminal *next_terminal;
 412
 413   /* Unique id for this terminal device. */
 414   int id;
 415
 416   /* The number of frames that are on this terminal. */
 417   int reference_count;
 418
 419   /* The type of the terminal device. */
 420   enum output_method type;
 421
 422   /* The name of the terminal device.  Do not use this to uniquely
 423      identify a terminal; the same device may be opened multiple
 424      times. */
 425   char *name;
 426
 427   /* The terminal's keyboard object. */
 428   struct kboard *kboard;
 429
 430 #ifdef HAVE_WINDOW_SYSTEM
 431   /* Cache of images.  */
 432   struct image_cache *image_cache;
 433 #endif /* HAVE_WINDOW_SYSTEM */
 434
 435   /* Device-type dependent data shared amongst all frames on this terminal.  */
 436   union display_info
 437   {
 438     struct tty_display_info *tty;     /* termchar.h */
 439     struct x_display_info *x;         /* xterm.h */
 440     struct w32_display_info *w32;     /* w32term.h */
 441     struct ns_display_info *ns;       /* nsterm.h */
 442   } display_info;
 443
 444 \f
 445   /* Coding-system to be used for encoding terminal output.  This
 446      structure contains information of a coding-system specified by
 447      the function `set-terminal-coding-system'.  Also see
 448      `safe_terminal_coding' in coding.h.  */
 449   struct coding_system *terminal_coding;
 450
 451   /* Coding-system of what is sent from terminal keyboard.  This
 452      structure contains information of a coding-system specified by
 453      the function `set-keyboard-coding-system'.  */
 454   struct coding_system *keyboard_coding;
 455
 456   /* Window-based redisplay interface for this device (0 for tty
 457      devices). */
 458   struct redisplay_interface *rif;
 459
 460   /* Frame-based redisplay interface. */
 461
 462   /* Text display hooks.  */
 463
 464   void (*cursor_to_hook) (struct frame *f, int vpos, int hpos);
 465   void (*raw_cursor_to_hook) (struct frame *, int, int);
 466
 467   void (*clear_to_end_hook) (struct frame *);
 468   void (*clear_frame_hook) (struct frame *);
 469   void (*clear_end_of_line_hook) (struct frame *, int);
 470
 471   void (*ins_del_lines_hook) (struct frame *f, int, int);
 472
 473   void (*insert_glyphs_hook) (struct frame *f, struct glyph *s, int n);
 474   void (*write_glyphs_hook) (struct frame *f, struct glyph *s, int n);
 475   void (*delete_glyphs_hook) (struct frame *, int);
 476
 477   void (*ring_bell_hook) (struct frame *f);
 478   void (*toggle_invisible_pointer_hook) (struct frame *f, bool invisible);
 479
 480   void (*reset_terminal_modes_hook) (struct terminal *);
 481   void (*set_terminal_modes_hook) (struct terminal *);
 482
 483   void (*update_begin_hook) (struct frame *);
 484   void (*update_end_hook) (struct frame *);
 485   void (*set_terminal_window_hook) (struct frame *, int);
 486
 487   /* Multi-frame and mouse support hooks.  */
 488
 489   /* Return the current position of the mouse.
 490
 491      Set *f to the frame the mouse is in, or zero if the mouse is in no
 492      Emacs frame.  If it is set to zero, all the other arguments are
 493      garbage.
 494
 495      If the motion started in a scroll bar, set *bar_window to the
 496      scroll bar's window, *part to the part the mouse is currently over,
 497      *x to the position of the mouse along the scroll bar, and *y to the
 498      overall length of the scroll bar.
 499
 500      Otherwise, set *bar_window to Qnil, and *x and *y to the column and
 501      row of the character cell the mouse is over.
 502
 503      Set *time to the time the mouse was at the returned position.  */
 504   void (*mouse_position_hook) (struct frame **f, int,
 505                                Lisp_Object *bar_window,
 506                                enum scroll_bar_part *part,
 507                                Lisp_Object *x,
 508                                Lisp_Object *y,
 509                                Time *);
 510
 511   /* When a frame's focus redirection is changed, this hook tells the
 512      window system code to re-decide where to put the highlight.  Under
 513      X, this means that Emacs lies about where the focus is.  */
 514   void (*frame_rehighlight_hook) (struct frame *);
 515
 516   /* If we're displaying frames using a window system that can stack
 517      frames on top of each other, this hook allows you to bring a frame
 518      to the front, or bury it behind all the other windows.  If this
 519      hook is zero, that means the terminal we're displaying on doesn't
 520      support overlapping frames, so there's no need to raise or lower
 521      anything.
 522
 523      If RAISE_FLAG, F is brought to the front, before all other
 524      windows.  If !RAISE_FLAG, F is sent to the back, behind all other
 525      windows.  */
 526   void (*frame_raise_lower_hook) (struct frame *f, bool raise_flag);
 527
 528   /* If the value of the frame parameter changed, this hook is called.
 529      For example, if going from fullscreen to not fullscreen this hook
 530      may do something OS dependent, like extended window manager hints on X11.  */
 531   void (*fullscreen_hook) (struct frame *f);
 532
 533   /* This hook is called to display menus.  */
 534   Lisp_Object (*menu_show_hook) (struct frame *f, int x, int y, int menuflags,
 535                                  Lisp_Object title, const char **error_name);
 536
 537   /* This hook is called to display popup dialog.  */
 538   Lisp_Object (*popup_dialog_hook) (struct frame *f, Lisp_Object header,
 539                                     Lisp_Object contents);
 540
 541   /* Scroll bar hooks.  */
 542
 543   /* The representation of scroll bars is determined by the code which
 544      implements them, except for one thing: they must be represented by
 545      lisp objects.  This allows us to place references to them in
 546      Lisp_Windows without worrying about those references becoming
 547      dangling references when the scroll bar is destroyed.
 548
 549      The window-system-independent portion of Emacs just refers to
 550      scroll bars via their windows, and never looks inside the scroll bar
 551      representation; it always uses hook functions to do all the
 552      scroll bar manipulation it needs.
 553
 554      The `vertical_scroll_bar' field of a Lisp_Window refers to that
 555      window's scroll bar, or is nil if the window doesn't have a
 556      scroll bar.
 557
 558      The `scroll_bars' and `condemned_scroll_bars' fields of a Lisp_Frame
 559      are free for use by the scroll bar implementation in any way it sees
 560      fit.  They are marked by the garbage collector.  */
 561
 562
 563   /* Set the vertical scroll bar for WINDOW to have its upper left corner
 564      at (TOP, LEFT), and be LENGTH rows high.  Set its handle to
 565      indicate that we are displaying PORTION characters out of a total
 566      of WHOLE characters, starting at POSITION.  If WINDOW doesn't yet
 567      have a scroll bar, create one for it.  */
 568   void (*set_vertical_scroll_bar_hook) (struct window *window,
 569                                         int portion, int whole,
 570                                         int position);
 571
 572
 573   /* Set the horizontal scroll bar for WINDOW to have its upper left
 574      corner at (TOP, LEFT), and be LENGTH rows high.  Set its handle to
 575      indicate that we are displaying PORTION characters out of a total
 576      of WHOLE characters, starting at POSITION.  If WINDOW doesn't yet
 577      have a scroll bar, create one for it.  */
 578   void (*set_horizontal_scroll_bar_hook) (struct window *window,
 579                                           int portion, int whole,
 580                                           int position);
 581
 582
 583   /* The following three hooks are used when we're doing a thorough
 584      redisplay of the frame.  We don't explicitly know which scroll bars
 585      are going to be deleted, because keeping track of when windows go
 586      away is a real pain - can you say set-window-configuration?
 587      Instead, we just assert at the beginning of redisplay that *all*
 588      scroll bars are to be removed, and then save scroll bars from the
 589      fiery pit when we actually redisplay their window.  */
 590
 591   /* Arrange for all scroll bars on FRAME to be removed at the next call
 592      to `*judge_scroll_bars_hook'.  A scroll bar may be spared if
 593      `*redeem_scroll_bar_hook' is applied to its window before the judgment.
 594
 595      This should be applied to each frame each time its window tree is
 596      redisplayed, even if it is not displaying scroll bars at the moment;
 597      if the HAS_SCROLL_BARS flag has just been turned off, only calling
 598      this and the judge_scroll_bars_hook will get rid of them.
 599
 600      If non-zero, this hook should be safe to apply to any frame,
 601      whether or not it can support scroll bars, and whether or not it is
 602      currently displaying them.  */
 603   void (*condemn_scroll_bars_hook) (struct frame *frame);
 604
 605   /* Unmark WINDOW's scroll bar for deletion in this judgment cycle.
 606      Note that it's okay to redeem a scroll bar that is not condemned.  */
 607   void (*redeem_scroll_bar_hook) (struct window *window);
 608
 609   /* Remove all scroll bars on FRAME that haven't been saved since the
 610      last call to `*condemn_scroll_bars_hook'.
 611
 612      This should be applied to each frame after each time its window
 613      tree is redisplayed, even if it is not displaying scroll bars at the
 614      moment; if the HAS_SCROLL_BARS flag has just been turned off, only
 615      calling this and condemn_scroll_bars_hook will get rid of them.
 616
 617      If non-zero, this hook should be safe to apply to any frame,
 618      whether or not it can support scroll bars, and whether or not it is
 619      currently displaying them.  */
 620   void (*judge_scroll_bars_hook) (struct frame *FRAME);
 621
 622 \f
 623   /* Called to read input events.
 624
 625      TERMINAL indicates which terminal device to read from.  Input
 626      events should be read into HOLD_QUIT.
 627
 628      A positive return value N indicates that N input events
 629      were read into BUF.
 630      Zero means no events were immediately available.
 631      A value of -1 means a transient read error, while -2 indicates
 632      that the device was closed (hangup), and it should be deleted.  */
 633   int (*read_socket_hook) (struct terminal *terminal,
 634                            struct input_event *hold_quit);
 635
 636   /* Called when a frame's display becomes entirely up to date.  */
 637   void (*frame_up_to_date_hook) (struct frame *);
 638
 639   /* Called when buffer flipping becomes unblocked after having
 640      previously been blocked.  Redisplay always blocks buffer flips
 641      while it runs.  */
 642   void (*buffer_flipping_unblocked_hook) (struct frame *);
 643
 644 \f
 645   /* Called to delete the device-specific portions of a frame that is
 646      on this terminal device. */
 647   void (*delete_frame_hook) (struct frame *);
 648
 649   /* Called after the last frame on this terminal is deleted, or when
 650      the display device was closed (hangup).
 651
 652      If this is NULL, then the generic delete_terminal is called
 653      instead.  Otherwise the hook must call delete_terminal itself.
 654
 655      The hook must check for and close any live frames that are still
 656      on the terminal.  delete_frame ensures that there are no live
 657      frames on the terminal when it calls this hook, so infinite
 658      recursion is prevented.  */
 659   void (*delete_terminal_hook) (struct terminal *);
 660 };
 661
 662 INLINE bool
 663 TERMINALP (Lisp_Object a)
 664 {
 665   return PSEUDOVECTORP (a, PVEC_TERMINAL);
 666 }
 667
 668 INLINE struct terminal *
 669 XTERMINAL (Lisp_Object a)
 670 {
 671   eassert (TERMINALP (a));
 672   return XUNTAG (a, Lisp_Vectorlike);
 673 }
 674
 675 /* Most code should use these functions to set Lisp fields in struct
 676    terminal.  */
 677 INLINE void
 678 tset_charset_list (struct terminal *t, Lisp_Object val)
 679 {
 680   t->charset_list = val;
 681 }
 682 INLINE void
 683 tset_selection_alist (struct terminal *t, Lisp_Object val)
 684 {
 685   t->Vselection_alist = val;
 686 }
 687
 688 /* Chain of all terminal devices currently in use.  */
 689 extern struct terminal *terminal_list;
 690
 691 #define FRAME_MUST_WRITE_SPACES(f) (FRAME_TTY (f)->must_write_spaces)
 692 #define FRAME_LINE_INS_DEL_OK(f) (FRAME_TTY (f)->line_ins_del_ok)
 693 #define FRAME_CHAR_INS_DEL_OK(f) (FRAME_TTY (f)->char_ins_del_ok)
 694 #define FRAME_SCROLL_REGION_OK(f) (FRAME_TTY (f)->scroll_region_ok)
 695 #define FRAME_SCROLL_REGION_COST(f) (FRAME_TTY (f)->scroll_region_cost)
 696 #define FRAME_MEMORY_BELOW_FRAME(f) (FRAME_TTY (f)->memory_below_frame)
 697
 698 #define FRAME_TERMINAL_CODING(f) ((f)->terminal->terminal_coding)
 699 #define FRAME_KEYBOARD_CODING(f) ((f)->terminal->keyboard_coding)
 700
 701 #define TERMINAL_TERMINAL_CODING(d) ((d)->terminal_coding)
 702 #define TERMINAL_KEYBOARD_CODING(d) ((d)->keyboard_coding)
 703
 704 #define FRAME_RIF(f) ((f)->terminal->rif)
 705
 706 #define FRAME_TERMINAL(f) ((f)->terminal)
 707
 708 /* Return true if the terminal device is not suspended.  */
 709 #define TERMINAL_ACTIVE_P(d)                                            \
 710   (((d)->type != output_termcap && (d)->type != output_msdos_raw)       \
 711    || (d)->display_info.tty->input)
 712
 713 /* Return font cache data for the specified terminal.  The historical
 714    name is grossly misleading, actually it is (NAME . FONT-LIST-CACHE).  */
 715 #if defined (HAVE_X_WINDOWS)
 716 #define TERMINAL_FONT_CACHE(t)                                          \
 717   (t->type == output_x_window ? t->display_info.x->name_list_element : Qnil)
 718 #elif defined (HAVE_NTGUI)
 719 #define TERMINAL_FONT_CACHE(t)                                          \
 720   (t->type == output_w32 ? t->display_info.w32->name_list_element : Qnil)
 721 #elif defined (HAVE_NS)
 722 #define TERMINAL_FONT_CACHE(t)                                          \
 723   (t->type == output_ns ? t->display_info.ns->name_list_element : Qnil)
 724 #endif
 725
 726 extern struct terminal *decode_live_terminal (Lisp_Object);
 727 extern struct terminal *decode_tty_terminal (Lisp_Object);
 728 extern struct terminal *get_named_terminal (const char *);
 729 extern struct terminal *create_terminal (enum output_method,
 730                                          struct redisplay_interface *);
 731 extern void delete_terminal (struct terminal *);
 732 extern Lisp_Object terminal_glyph_code (struct terminal *, int);
 733
 734 /* The initial terminal device, created by initial_term_init.  */
 735 extern struct terminal *initial_terminal;
 736
 737 extern unsigned char *encode_terminal_code (struct glyph *, int,
 738                                             struct coding_system *);
 739
 740 #ifdef HAVE_GPM
 741 extern void close_gpm (int gpm_fd);
 742 #endif
 743
 744 #ifdef WINDOWSNT
 745 extern int cursorX (struct tty_display_info *);
 746 extern int cursorY (struct tty_display_info *);
 747 #else
 748 #define cursorX(t)  curX(t)
 749 #define cursorY(t)  curY(t)
 750 #endif
 751
 752 INLINE_HEADER_END
 753
 754 #endif /* EMACS_TERMHOOKS_H */