src/termhooks.h

   1 /* Parameters and display hooks for terminal devices.
   2
   3 Copyright (C) 1985-1986, 1993-1994, 2001-2012  Free Software Foundation, Inc.
   4
   5 This file is part of GNU Emacs.
   6
   7 GNU Emacs is free software: you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation, either version 3 of the License, or
  10 (at your option) any later version.
  11
  12 GNU Emacs is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 \f
  21 /* Miscellanea.   */
  22
  23 #include "systime.h" /* for Time */
  24
  25 INLINE_HEADER_BEGIN
  26 #ifndef TERMHOOKS_INLINE
  27 # define TERMHOOKS_INLINE INLINE
  28 #endif
  29
  30 struct glyph;
  31 struct frame;
  32 \f
  33
  34 enum scroll_bar_part {
  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 };
  45
  46 /* If the value of the frame parameter changed, whis hook is called.
  47    For example, if going from fullscreen to not fullscreen this hook
  48    may do something OS dependent, like extended window manager hints on X11.  */
  49 extern void (*fullscreen_hook) (struct frame *f);
  50
  51 \f
  52 /* Input queue declarations and hooks.  */
  53
  54 enum event_kind
  55 {
  56   NO_EVENT,                     /* nothing happened.  This should never
  57                                    actually appear in the event queue.  */
  58
  59   ASCII_KEYSTROKE_EVENT,        /* The ASCII code is in .code, perhaps
  60                                    with modifiers applied.
  61                                    .modifiers holds the state of the
  62                                    modifier keys.
  63                                    .frame_or_window is the frame in
  64                                    which the key was typed.
  65                                    .timestamp gives a timestamp (in
  66                                    milliseconds) for the keystroke.  */
  67   MULTIBYTE_CHAR_KEYSTROKE_EVENT,       /* The multibyte char code is in .code,
  68                                    perhaps with modifiers applied.
  69                                    The others are the same as
  70                                    ASCII_KEYSTROKE_EVENT.  */
  71   NON_ASCII_KEYSTROKE_EVENT,    /* .code is a number identifying the
  72                                    function key.  A code N represents
  73                                    a key whose name is
  74                                    function_key_names[N]; function_key_names
  75                                    is a table in keyboard.c to which you
  76                                    should feel free to add missing keys.
  77                                    .modifiers holds the state of the
  78                                    modifier keys.
  79                                    .frame_or_window is the frame in
  80                                    which the key was typed.
  81                                    .timestamp gives a timestamp (in
  82                                    milliseconds) for the keystroke.  */
  83   TIMER_EVENT,                  /* A timer fired.  */
  84   MOUSE_CLICK_EVENT,            /* The button number is in .code; it must
  85                                    be >= 0 and < NUM_MOUSE_BUTTONS, defined
  86                                    below.
  87                                    .modifiers holds the state of the
  88                                    modifier keys.
  89                                    .x and .y give the mouse position,
  90                                    in characters, within the window.
  91                                    .frame_or_window gives the frame
  92                                    the mouse click occurred in.
  93                                    .timestamp gives a timestamp (in
  94                                    milliseconds) for the click.  */
  95   WHEEL_EVENT,                  /* A wheel event is generated by a
  96                                    wheel on a mouse (e.g., MS
  97                                    Intellimouse).
  98                                    .modifiers holds the rotate
  99                                    direction (up or down), and the
 100                                    state of the modifier keys.
 101                                    .x and .y give the mouse position,
 102                                    in characters, within the window.
 103                                    .frame_or_window gives the frame
 104                                    the wheel event occurred in.
 105                                    .timestamp gives a timestamp (in
 106                                    milliseconds) for the event.  */
 107   HORIZ_WHEEL_EVENT,            /* A wheel event generated by a second
 108                                    horizontal wheel that is present on some
 109                                    mice. See WHEEL_EVENT.  */
 110 #ifdef HAVE_NTGUI
 111   LANGUAGE_CHANGE_EVENT,        /* A LANGUAGE_CHANGE_EVENT is
 112                                    generated when HAVE_NTGUI or on Mac OS
 113                                    when the keyboard layout or input
 114                                    language is changed by the
 115                                    user.  */
 116 #endif
 117   SCROLL_BAR_CLICK_EVENT,       /* .code gives the number of the mouse button
 118                                    that was clicked.
 119                                    .modifiers holds the state of the modifier
 120                                    keys.
 121                                    .part is a lisp symbol indicating which
 122                                    part of the scroll bar got clicked.
 123                                    .x gives the distance from the start of the
 124                                    scroll bar of the click; .y gives the total
 125                                    length of the scroll bar.
 126                                    .frame_or_window gives the window
 127                                    whose scroll bar was clicked in.
 128                                    .timestamp gives a timestamp (in
 129                                    milliseconds) for the click.  */
 130   SELECTION_REQUEST_EVENT,      /* Another X client wants a selection from us.
 131                                    See `struct selection_input_event'.  */
 132   SELECTION_CLEAR_EVENT,        /* Another X client cleared our selection.  */
 133   BUFFER_SWITCH_EVENT,          /* A process filter has switched buffers.  */
 134   DELETE_WINDOW_EVENT,          /* An X client said "delete this window".  */
 135   MENU_BAR_EVENT,               /* An event generated by the menu bar.
 136                                    The frame_or_window field's cdr holds the
 137                                    Lisp-level event value.
 138                                    (Only the toolkit version uses these.)  */
 139   ICONIFY_EVENT,                /* An X client iconified this window.  */
 140   DEICONIFY_EVENT,              /* An X client deiconified this window.  */
 141   MENU_BAR_ACTIVATE_EVENT,      /* A button press in the menu bar
 142                                    (toolkit version only).  */
 143   DRAG_N_DROP_EVENT,            /* A drag-n-drop event is generated when
 144                                    files selected outside of Emacs are dropped
 145                                    onto an Emacs window.
 146                                    .modifiers holds the state of the
 147                                    modifier keys.
 148                                    .x and .y give the mouse position,
 149                                    in characters, within the window.
 150                                    .frame_or_window is the frame in
 151                                    which the drop was made.
 152                                    .arg is a platform-dependent
 153                                    representation of the dropped items.
 154                                    .timestamp gives a timestamp (in
 155                                    milliseconds) for the click.  */
 156   USER_SIGNAL_EVENT,            /* A user signal.
 157                                    code is a number identifying it,
 158                                    index into lispy_user_signals.  */
 159
 160   /* Help events.  Member `frame_or_window' of the input_event is the
 161      frame on which the event occurred, and member `arg' contains
 162      the help to show.  */
 163   HELP_EVENT,
 164
 165   /* An event from a tool-bar.  Member `arg' of the input event
 166      contains the tool-bar item selected.  If `frame_or_window'
 167      and `arg' are equal, this is a prefix event.  */
 168   TOOL_BAR_EVENT,
 169
 170   /* Queued from XTread_socket on FocusIn events.  Translated into
 171      `switch-frame' events in kbd_buffer_get_event, if necessary.  */
 172   FOCUS_IN_EVENT,
 173
 174   /* Generated when mouse moves over window not currently selected.  */
 175   SELECT_WINDOW_EVENT,
 176
 177   /* Queued from XTread_socket when session manager sends
 178      save yourself before shutdown. */
 179   SAVE_SESSION_EVENT
 180
 181 #ifdef HAVE_GPM
 182   , GPM_CLICK_EVENT
 183 #endif
 184
 185 #ifdef HAVE_DBUS
 186   , DBUS_EVENT
 187 #endif
 188
 189   , CONFIG_CHANGED_EVENT
 190
 191 #ifdef HAVE_NTGUI
 192   /* Generated when an APPCOMMAND event is received, in response to
 193      Multimedia or Internet buttons on some keyboards.
 194      Such keys are available as normal function keys on X through the
 195      Xkeyboard extension.
 196      On Windows, some of them get mapped to normal function key events,
 197      but others need to be handled by APPCOMMAND. Handling them all as
 198      APPCOMMAND events means they can be disabled
 199      (w32-pass-multimedia-buttons-to-system), important on Windows since
 200      the system never sees these keys if Emacs claims to handle them.
 201      On X, the window manager seems to grab the keys it wants
 202      first, so this is not a problem there.  */
 203   , MULTIMEDIA_KEY_EVENT
 204 #endif
 205
 206 #ifdef HAVE_NS
 207   /* Generated when native multi-keystroke input method is used to modify
 208      tentative or indicative text display. */
 209   , NS_TEXT_EVENT
 210   /* Non-key system events (e.g. application menu events) */
 211   , NS_NONKEY_EVENT
 212 #endif
 213
 214 };
 215
 216 /* If a struct input_event has a kind which is SELECTION_REQUEST_EVENT
 217    or SELECTION_CLEAR_EVENT, then its contents are really described
 218    by `struct selection_input_event'; see xterm.h.  */
 219
 220 /* The keyboard input buffer is an array of these structures.  Each one
 221    represents some sort of input event - a keystroke, a mouse click, or
 222    a window system event.  These get turned into their lispy forms when
 223    they are removed from the event queue.  */
 224
 225 struct input_event
 226 {
 227   /* What kind of event was this?  */
 228   enum event_kind kind;
 229
 230   /* For an ASCII_KEYSTROKE_EVENT and MULTIBYTE_CHAR_KEYSTROKE_EVENT,
 231      this is the character.
 232      For a NON_ASCII_KEYSTROKE_EVENT, this is the keysym code.
 233      For a mouse event, this is the button number.
 234      For a HELP_EVENT, this is the position within the object
 235       (stored in ARG below) where the help was found.  */
 236   /* In WindowsNT, for a mouse wheel event, this is the delta.  */
 237   ptrdiff_t code;
 238   enum scroll_bar_part part;
 239
 240   int modifiers;                /* See enum below for interpretation.  */
 241
 242   Lisp_Object x, y;
 243   Time timestamp;
 244
 245   /* This field is copied into a vector while the event is in
 246      the queue, so that garbage collections won't kill it.  */
 247   Lisp_Object frame_or_window;
 248
 249   /* Additional event argument.  This is used for TOOL_BAR_EVENTs and
 250      HELP_EVENTs and avoids calling Fcons during signal handling.  */
 251   Lisp_Object arg;
 252 };
 253
 254 #define EVENT_INIT(event) memset (&(event), 0, sizeof (struct input_event))
 255
 256 /* Bits in the modifiers member of the input_event structure.
 257    Note that reorder_modifiers assumes that the bits are in canonical
 258    order.
 259
 260    The modifiers applied to mouse clicks are rather ornate.  The
 261    window-system-specific code should store mouse clicks with
 262    up_modifier or down_modifier set.  Having an explicit down modifier
 263    simplifies some of window-system-independent code; without it, the
 264    code would have to recognize down events by checking if the event
 265    is a mouse click lacking the click and drag modifiers.
 266
 267    The window-system independent code turns all up_modifier events
 268    bits into drag_modifier, click_modifier, double_modifier, or
 269    triple_modifier events.  The click_modifier has no written
 270    representation in the names of the symbols used as event heads,
 271    but it does appear in the Qevent_symbol_components property of the
 272    event heads.  */
 273 enum {
 274   up_modifier   =   1,          /* Only used on mouse buttons - always
 275                                    turned into a click or a drag modifier
 276                                    before lisp code sees the event.  */
 277   down_modifier =   2,          /* Only used on mouse buttons.  */
 278   drag_modifier =   4,          /* This is never used in the event
 279                                    queue; it's only used internally by
 280                                    the window-system-independent code.  */
 281   click_modifier=   8,          /* See drag_modifier.  */
 282   double_modifier= 16,          /* See drag_modifier.  */
 283   triple_modifier= 32,          /* See drag_modifier.  */
 284
 285   /* The next four modifier bits are used also in keyboard events at
 286      the Lisp level.
 287
 288      It's probably not the greatest idea to use the 2^28 bit for any
 289      modifier.  It may or may not be the sign bit, depending on
 290      FIXNUM_BITS, so using it to represent a modifier key means that
 291      characters thus modified have different integer equivalents
 292      depending on the architecture they're running on.  Oh, and
 293      applying XINT to a character whose 2^28 bit is set might sign-extend
 294      it, so you get a bunch of bits in the mask you didn't want.
 295
 296      The CHAR_ macros are defined in lisp.h.  */
 297   alt_modifier  =  CHAR_ALT,    /* Under X, the XK_Alt_[LR] keysyms.  */
 298   super_modifier=  CHAR_SUPER,  /* Under X, the XK_Super_[LR] keysyms.  */
 299   hyper_modifier=  CHAR_HYPER,  /* Under X, the XK_Hyper_[LR] keysyms.  */
 300   shift_modifier=  CHAR_SHIFT,
 301   ctrl_modifier =  CHAR_CTL,
 302   meta_modifier =  CHAR_META    /* Under X, the XK_Meta_[LR] keysyms.  */
 303 };
 304
 305 #ifdef HAVE_GPM
 306 #include <gpm.h>
 307 extern int handle_one_term_event (struct tty_display_info *, Gpm_Event *, struct input_event *);
 308 #ifndef HAVE_WINDOW_SYSTEM
 309 extern void term_mouse_moveto (int, int);
 310 #endif
 311
 312 /* The device for which we have enabled gpm support.  */
 313 extern struct tty_display_info *gpm_tty;
 314 #endif
 315
 316 \f
 317 struct ns_display_info;
 318 struct x_display_info;
 319 struct w32_display_info;
 320
 321 /* Terminal-local parameters. */
 322 struct terminal
 323 {
 324   /* This is for Lisp; the terminal code does not refer to it.  */
 325   struct vectorlike_header header;
 326
 327   /* Parameter alist of this terminal.  */
 328   Lisp_Object param_alist;
 329
 330   /* List of charsets supported by the terminal.  It is set by
 331      Fset_terminal_coding_system_internal along with
 332      the member terminal_coding.  */
 333   Lisp_Object charset_list;
 334
 335   /* This is an association list containing the X selections that
 336      Emacs might own on this terminal.  Each element has the form
 337        (SELECTION-NAME SELECTION-VALUE SELECTION-TIMESTAMP FRAME)
 338      SELECTION-NAME is a lisp symbol, whose name is the name of an X Atom.
 339      SELECTION-VALUE is the value that emacs owns for that selection.
 340       It may be any kind of Lisp object.
 341      SELECTION-TIMESTAMP is the time at which emacs began owning this
 342       selection, as a cons of two 16-bit numbers (making a 32 bit
 343       time.)
 344      FRAME is the frame for which we made the selection.  If there is
 345       an entry in this alist, then it can be assumed that Emacs owns
 346       that selection.
 347      The only (eq) parts of this list that are visible from Lisp are
 348     the selection-values.  */
 349   Lisp_Object Vselection_alist;
 350
 351   /* All fields before `next_terminal' should be Lisp_Object and are traced
 352      by the GC.  All fields afterwards are ignored by the GC.  */
 353
 354   /* Chain of all terminal devices. */
 355   struct terminal *next_terminal;
 356
 357   /* Unique id for this terminal device. */
 358   int id;
 359
 360   /* The number of frames that are on this terminal. */
 361   int reference_count;
 362
 363   /* The type of the terminal device. */
 364   enum output_method type;
 365
 366   /* The name of the terminal device.  Do not use this to uniquely
 367      identify a terminal; the same device may be opened multiple
 368      times. */
 369   char *name;
 370
 371   /* The terminal's keyboard object. */
 372   struct kboard *kboard;
 373
 374 #ifdef HAVE_WINDOW_SYSTEM
 375   /* Cache of images.  */
 376   struct image_cache *image_cache;
 377 #endif /* HAVE_WINDOW_SYSTEM */
 378
 379   /* Device-type dependent data shared amongst all frames on this terminal. */
 380   union display_info
 381   {
 382     struct tty_display_info *tty;     /* termchar.h */
 383     struct x_display_info *x;         /* xterm.h */
 384     struct w32_display_info *w32;     /* w32term.h */
 385     struct ns_display_info *ns;       /* nsterm.h */
 386   } display_info;
 387
 388 \f
 389   /* Coding-system to be used for encoding terminal output.  This
 390      structure contains information of a coding-system specified by
 391      the function `set-terminal-coding-system'.  Also see
 392      `safe_terminal_coding' in coding.h.  */
 393   struct coding_system *terminal_coding;
 394
 395   /* Coding-system of what is sent from terminal keyboard.  This
 396      structure contains information of a coding-system specified by
 397      the function `set-keyboard-coding-system'.  */
 398   struct coding_system *keyboard_coding;
 399
 400   /* Terminal characteristics. */
 401   /* XXX Are these really used on non-termcap displays? */
 402
 403   int must_write_spaces;        /* Nonzero means spaces in the text must
 404                                    actually be output; can't just skip over
 405                                    some columns to leave them blank.  */
 406   int fast_clear_end_of_line;   /* Nonzero means terminal has a `ce' string */
 407
 408   int line_ins_del_ok;          /* Terminal can insert and delete lines */
 409   int char_ins_del_ok;          /* Terminal can insert and delete chars */
 410   int scroll_region_ok;         /* Terminal supports setting the scroll
 411                                    window */
 412   int scroll_region_cost;       /* Cost of setting the scroll window,
 413                                    measured in characters. */
 414   int memory_below_frame;       /* Terminal remembers lines scrolled
 415                                    off bottom */
 416
 417 #if 0  /* These are not used anywhere. */
 418   /* EMACS_INT baud_rate; */    /* Output speed in baud */
 419   int min_padding_speed;        /* Speed below which no padding necessary. */
 420   int dont_calculate_costs;     /* Nonzero means don't bother computing
 421                                    various cost tables; we won't use them. */
 422 #endif
 423
 424 \f
 425   /* Window-based redisplay interface for this device (0 for tty
 426      devices). */
 427   struct redisplay_interface *rif;
 428
 429   /* Frame-based redisplay interface. */
 430
 431   /* Text display hooks.  */
 432
 433   void (*cursor_to_hook) (struct frame *f, int vpos, int hpos);
 434   void (*raw_cursor_to_hook) (struct frame *, int, int);
 435
 436   void (*clear_to_end_hook) (struct frame *);
 437   void (*clear_frame_hook) (struct frame *);
 438   void (*clear_end_of_line_hook) (struct frame *, int);
 439
 440   void (*ins_del_lines_hook) (struct frame *f, int, int);
 441
 442   void (*insert_glyphs_hook) (struct frame *f, struct glyph *s, int n);
 443   void (*write_glyphs_hook) (struct frame *f, struct glyph *s, int n);
 444   void (*delete_glyphs_hook) (struct frame *, int);
 445
 446   void (*ring_bell_hook) (struct frame *f);
 447   void (*toggle_invisible_pointer_hook) (struct frame *f, int invisible);
 448
 449   void (*reset_terminal_modes_hook) (struct terminal *);
 450   void (*set_terminal_modes_hook) (struct terminal *);
 451
 452   void (*update_begin_hook) (struct frame *);
 453   void (*update_end_hook) (struct frame *);
 454   void (*set_terminal_window_hook) (struct frame *, int);
 455
 456   /* Multi-frame and mouse support hooks.  */
 457
 458   /* Return the current position of the mouse.
 459
 460      Set *f to the frame the mouse is in, or zero if the mouse is in no
 461      Emacs frame.  If it is set to zero, all the other arguments are
 462      garbage.
 463
 464      If the motion started in a scroll bar, set *bar_window to the
 465      scroll bar's window, *part to the part the mouse is currently over,
 466      *x to the position of the mouse along the scroll bar, and *y to the
 467      overall length of the scroll bar.
 468
 469      Otherwise, set *bar_window to Qnil, and *x and *y to the column and
 470      row of the character cell the mouse is over.
 471
 472      Set *time to the time the mouse was at the returned position.
 473
 474      This should clear mouse_moved until the next motion
 475      event arrives.  */
 476   void (*mouse_position_hook) (struct frame **f, int,
 477                                Lisp_Object *bar_window,
 478                                enum scroll_bar_part *part,
 479                                Lisp_Object *x,
 480                                Lisp_Object *y,
 481                                Time *);
 482
 483   /* The window system handling code should set this if the mouse has
 484      moved since the last call to the mouse_position_hook.  Calling that
 485      hook should clear this.  */
 486   int mouse_moved;
 487
 488   /* When a frame's focus redirection is changed, this hook tells the
 489      window system code to re-decide where to put the highlight.  Under
 490      X, this means that Emacs lies about where the focus is.  */
 491   void (*frame_rehighlight_hook) (struct frame *);
 492
 493   /* If we're displaying frames using a window system that can stack
 494      frames on top of each other, this hook allows you to bring a frame
 495      to the front, or bury it behind all the other windows.  If this
 496      hook is zero, that means the terminal we're displaying on doesn't
 497      support overlapping frames, so there's no need to raise or lower
 498      anything.
 499
 500      If RAISE_FLAG is non-zero, F is brought to the front, before all other
 501      windows.  If RAISE_FLAG is zero, F is sent to the back, behind all other
 502      windows.  */
 503   void (*frame_raise_lower_hook) (struct frame *f, int raise_flag);
 504
 505   /* If the value of the frame parameter changed, whis hook is called.
 506      For example, if going from fullscreen to not fullscreen this hook
 507      may do something OS dependent, like extended window manager hints on X11.  */
 508   void (*fullscreen_hook) (struct frame *f);
 509
 510   \f
 511   /* Scroll bar hooks.  */
 512
 513   /* The representation of scroll bars is determined by the code which
 514      implements them, except for one thing: they must be represented by
 515      lisp objects.  This allows us to place references to them in
 516      Lisp_Windows without worrying about those references becoming
 517      dangling references when the scroll bar is destroyed.
 518
 519      The window-system-independent portion of Emacs just refers to
 520      scroll bars via their windows, and never looks inside the scroll bar
 521      representation; it always uses hook functions to do all the
 522      scroll bar manipulation it needs.
 523
 524      The `vertical_scroll_bar' field of a Lisp_Window refers to that
 525      window's scroll bar, or is nil if the window doesn't have a
 526      scroll bar.
 527
 528      The `scroll_bars' and `condemned_scroll_bars' fields of a Lisp_Frame
 529      are free for use by the scroll bar implementation in any way it sees
 530      fit.  They are marked by the garbage collector.  */
 531
 532
 533   /* Set the vertical scroll bar for WINDOW to have its upper left corner
 534      at (TOP, LEFT), and be LENGTH rows high.  Set its handle to
 535      indicate that we are displaying PORTION characters out of a total
 536      of WHOLE characters, starting at POSITION.  If WINDOW doesn't yet
 537      have a scroll bar, create one for it.  */
 538   void (*set_vertical_scroll_bar_hook) (struct window *window,
 539                                         int portion, int whole,
 540                                         int position);
 541
 542
 543   /* The following three hooks are used when we're doing a thorough
 544      redisplay of the frame.  We don't explicitly know which scroll bars
 545      are going to be deleted, because keeping track of when windows go
 546      away is a real pain - can you say set-window-configuration?
 547      Instead, we just assert at the beginning of redisplay that *all*
 548      scroll bars are to be removed, and then save scroll bars from the
 549      fiery pit when we actually redisplay their window.  */
 550
 551   /* Arrange for all scroll bars on FRAME to be removed at the next call
 552      to `*judge_scroll_bars_hook'.  A scroll bar may be spared if
 553      `*redeem_scroll_bar_hook' is applied to its window before the judgment.
 554
 555      This should be applied to each frame each time its window tree is
 556      redisplayed, even if it is not displaying scroll bars at the moment;
 557      if the HAS_SCROLL_BARS flag has just been turned off, only calling
 558      this and the judge_scroll_bars_hook will get rid of them.
 559
 560      If non-zero, this hook should be safe to apply to any frame,
 561      whether or not it can support scroll bars, and whether or not it is
 562      currently displaying them.  */
 563   void (*condemn_scroll_bars_hook) (struct frame *frame);
 564
 565   /* Unmark WINDOW's scroll bar for deletion in this judgment cycle.
 566      Note that it's okay to redeem a scroll bar that is not condemned.  */
 567   void (*redeem_scroll_bar_hook) (struct window *window);
 568
 569   /* Remove all scroll bars on FRAME that haven't been saved since the
 570      last call to `*condemn_scroll_bars_hook'.
 571
 572      This should be applied to each frame after each time its window
 573      tree is redisplayed, even if it is not displaying scroll bars at the
 574      moment; if the HAS_SCROLL_BARS flag has just been turned off, only
 575      calling this and condemn_scroll_bars_hook will get rid of them.
 576
 577      If non-zero, this hook should be safe to apply to any frame,
 578      whether or not it can support scroll bars, and whether or not it is
 579      currently displaying them.  */
 580   void (*judge_scroll_bars_hook) (struct frame *FRAME);
 581
 582 \f
 583   /* Called to read input events.
 584
 585      TERMINAL indicates which terminal device to read from.  Input
 586      events should be read into HOLD_QUIT.
 587
 588      A positive return value indicates that that many input events
 589      were read into BUF.
 590      Zero means no events were immediately available.
 591      A value of -1 means a transient read error, while -2 indicates
 592      that the device was closed (hangup), and it should be deleted.  */
 593   int (*read_socket_hook) (struct terminal *terminal,
 594                            struct input_event *hold_quit);
 595
 596   /* Called when a frame's display becomes entirely up to date.  */
 597   void (*frame_up_to_date_hook) (struct frame *);
 598
 599 \f
 600   /* Called to delete the device-specific portions of a frame that is
 601      on this terminal device. */
 602   void (*delete_frame_hook) (struct frame *);
 603
 604   /* Called after the last frame on this terminal is deleted, or when
 605      the display device was closed (hangup).
 606
 607      If this is NULL, then the generic delete_terminal is called
 608      instead.  Otherwise the hook must call delete_terminal itself.
 609
 610      The hook must check for and close any live frames that are still
 611      on the terminal.  delete_frame ensures that there are no live
 612      frames on the terminal when it calls this hook, so infinite
 613      recursion is prevented.  */
 614   void (*delete_terminal_hook) (struct terminal *);
 615 };
 616
 617 /* Most code should use these functions to set Lisp fields in struct
 618    terminal.  */
 619 TERMHOOKS_INLINE void
 620 tset_charset_list (struct terminal *t, Lisp_Object val)
 621 {
 622   t->charset_list = val;
 623 }
 624 TERMHOOKS_INLINE void
 625 tset_selection_alist (struct terminal *t, Lisp_Object val)
 626 {
 627   t->Vselection_alist = val;
 628 }
 629
 630 /* Chain of all terminal devices currently in use. */
 631 extern struct terminal *terminal_list;
 632
 633 #define FRAME_MUST_WRITE_SPACES(f) ((f)->terminal->must_write_spaces)
 634 #define FRAME_FAST_CLEAR_END_OF_LINE(f) ((f)->terminal->fast_clear_end_of_line)
 635 #define FRAME_LINE_INS_DEL_OK(f) ((f)->terminal->line_ins_del_ok)
 636 #define FRAME_CHAR_INS_DEL_OK(f) ((f)->terminal->char_ins_del_ok)
 637 #define FRAME_SCROLL_REGION_OK(f) ((f)->terminal->scroll_region_ok)
 638 #define FRAME_SCROLL_REGION_COST(f) ((f)->terminal->scroll_region_cost)
 639 #define FRAME_MEMORY_BELOW_FRAME(f) ((f)->terminal->memory_below_frame)
 640
 641 #define FRAME_TERMINAL_CODING(f) ((f)->terminal->terminal_coding)
 642 #define FRAME_KEYBOARD_CODING(f) ((f)->terminal->keyboard_coding)
 643
 644 #define TERMINAL_TERMINAL_CODING(d) ((d)->terminal_coding)
 645 #define TERMINAL_KEYBOARD_CODING(d) ((d)->keyboard_coding)
 646
 647 #define FRAME_RIF(f) ((f)->terminal->rif)
 648
 649 #define FRAME_TERMINAL(f) ((f)->terminal)
 650
 651 /* Return true if the terminal device is not suspended. */
 652 #define TERMINAL_ACTIVE_P(d) (((d)->type != output_termcap && (d)->type !=output_msdos_raw) || (d)->display_info.tty->input)
 653
 654 extern struct terminal *get_terminal (Lisp_Object terminal, int);
 655 extern struct terminal *create_terminal (void);
 656 extern void delete_terminal (struct terminal *);
 657
 658 /* The initial terminal device, created by initial_term_init. */
 659 extern struct terminal *initial_terminal;
 660
 661 extern unsigned char *encode_terminal_code (struct glyph *, int,
 662                                             struct coding_system *);
 663
 664 #ifdef HAVE_GPM
 665 extern void close_gpm (int gpm_fd);
 666 #endif
 667
 668 INLINE_HEADER_END