src/termhooks.h

   1 /* Parameters and display hooks for terminal devices.
   2    Copyright (C) 1985, 1986, 1993, 1994, 2001, 2002, 2003, 2004,
   3                  2005, 2006, 2007, 2008, 2009  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 struct glyph;
  24 struct frame;
  25 \f
  26
  27 enum scroll_bar_part {
  28   scroll_bar_above_handle,
  29   scroll_bar_handle,
  30   scroll_bar_below_handle,
  31   scroll_bar_up_arrow,
  32   scroll_bar_down_arrow,
  33   scroll_bar_to_top,
  34   scroll_bar_to_bottom,
  35   scroll_bar_end_scroll,
  36   scroll_bar_move_ratio
  37 };
  38
  39 /* If the value of the frame parameter changed, whis hook is called.
  40    For example, if going from fullscreen to not fullscreen this hook
  41    may do something OS dependent, like extended window manager hints on X11.  */
  42 extern void (*fullscreen_hook) P_ ((struct frame *f));
  43
  44 \f
  45 /* Input queue declarations and hooks.  */
  46
  47 /* Expedient hack: only provide the below definitions to files that
  48    are prepared to handle lispy things.  CONSP is defined if lisp.h
  49    has been included before this file.  */
  50 #ifdef CONSP
  51
  52 enum event_kind
  53 {
  54   NO_EVENT,                     /* nothing happened.  This should never
  55                                    actually appear in the event queue.  */
  56
  57   ASCII_KEYSTROKE_EVENT,        /* The ASCII code is in .code, perhaps
  58                                    with modifiers applied.
  59                                    .modifiers holds the state of the
  60                                    modifier keys.
  61                                    .frame_or_window is the frame in
  62                                    which the key was typed.
  63                                    .timestamp gives a timestamp (in
  64                                    milliseconds) for the keystroke.  */
  65   MULTIBYTE_CHAR_KEYSTROKE_EVENT,       /* The multibyte char code is in .code,
  66                                    perhaps with modifiers applied.
  67                                    The others are the same as
  68                                    ASCII_KEYSTROKE_EVENT.  */
  69   NON_ASCII_KEYSTROKE_EVENT,    /* .code is a number identifying the
  70                                    function key.  A code N represents
  71                                    a key whose name is
  72                                    function_key_names[N]; function_key_names
  73                                    is a table in keyboard.c to which you
  74                                    should feel free to add missing keys.
  75                                    .modifiers holds the state of the
  76                                    modifier keys.
  77                                    .frame_or_window is the frame in
  78                                    which the key was typed.
  79                                    .timestamp gives a timestamp (in
  80                                    milliseconds) for the keystroke.  */
  81   TIMER_EVENT,                  /* A timer fired.  */
  82   MOUSE_CLICK_EVENT,            /* The button number is in .code; it must
  83                                    be >= 0 and < NUM_MOUSE_BUTTONS, defined
  84                                    below.
  85                                    .modifiers holds the state of the
  86                                    modifier keys.
  87                                    .x and .y give the mouse position,
  88                                    in characters, within the window.
  89                                    .frame_or_window gives the frame
  90                                    the mouse click occurred in.
  91                                    .timestamp gives a timestamp (in
  92                                    milliseconds) for the click.  */
  93   WHEEL_EVENT,                  /* A wheel event is generated by a
  94                                    wheel on a mouse (e.g., MS
  95                                    Intellimouse).
  96                                    .modifiers holds the rotate
  97                                    direction (up or down), and the
  98                                    state of the modifier keys.
  99                                    .x and .y give the mouse position,
 100                                    in characters, within the window.
 101                                    .frame_or_window gives the frame
 102                                    the wheel event occurred in.
 103                                    .timestamp gives a timestamp (in
 104                                    milliseconds) for the event.  */
 105   HORIZ_WHEEL_EVENT,            /* A wheel event generated by a second
 106                                    horizontal wheel that is present on some
 107                                    mice. See WHEEL_EVENT.  */
 108 #if defined (WINDOWSNT)
 109   LANGUAGE_CHANGE_EVENT,        /* A LANGUAGE_CHANGE_EVENT is
 110                                    generated on WINDOWSNT or Mac OS
 111                                    when the keyboard layout or input
 112                                    language is changed by the
 113                                    user.  */
 114 #endif
 115   SCROLL_BAR_CLICK_EVENT,       /* .code gives the number of the mouse button
 116                                    that was clicked.
 117                                    .modifiers holds the state of the modifier
 118                                    keys.
 119                                    .part is a lisp symbol indicating which
 120                                    part of the scroll bar got clicked.
 121                                    .x gives the distance from the start of the
 122                                    scroll bar of the click; .y gives the total
 123                                    length of the scroll bar.
 124                                    .frame_or_window gives the window
 125                                    whose scroll bar was clicked in.
 126                                    .timestamp gives a timestamp (in
 127                                    milliseconds) for the click.  */
 128   SELECTION_REQUEST_EVENT,      /* Another X client wants a selection from us.
 129                                    See `struct selection_input_event'.  */
 130   SELECTION_CLEAR_EVENT,        /* Another X client cleared our selection.  */
 131   BUFFER_SWITCH_EVENT,          /* A process filter has switched buffers.  */
 132   DELETE_WINDOW_EVENT,          /* An X client said "delete this window".  */
 133   MENU_BAR_EVENT,               /* An event generated by the menu bar.
 134                                    The frame_or_window field's cdr holds the
 135                                    Lisp-level event value.
 136                                    (Only the toolkit version uses these.)  */
 137   ICONIFY_EVENT,                /* An X client iconified this window.  */
 138   DEICONIFY_EVENT,              /* An X client deiconified this window.  */
 139   MENU_BAR_ACTIVATE_EVENT,      /* A button press in the menu bar
 140                                    (toolkit version only).  */
 141   DRAG_N_DROP_EVENT,            /* A drag-n-drop event is generated when
 142                                    files selected outside of Emacs are dropped
 143                                    onto an Emacs window.
 144                                    .modifiers holds the state of the
 145                                    modifier keys.
 146                                    .x and .y give the mouse position,
 147                                    in characters, within the window.
 148                                    .frame_or_window is the frame in
 149                                    which the drop was made.
 150                                    .arg is a platform-dependent
 151                                    representation of the dropped items.
 152                                    .timestamp gives a timestamp (in
 153                                    milliseconds) for the click.  */
 154   USER_SIGNAL_EVENT,            /* A user signal.
 155                                    code is a number identifying it,
 156                                    index into lispy_user_signals.  */
 157
 158   /* Help events.  Member `frame_or_window' of the input_event is the
 159      frame on which the event occurred, and member `arg' contains
 160      the help to show.  */
 161   HELP_EVENT,
 162
 163   /* An event from a tool-bar.  Member `arg' of the input event
 164      contains the tool-bar item selected.  If `frame_or_window'
 165      and `arg' are equal, this is a prefix event.  */
 166   TOOL_BAR_EVENT,
 167
 168   /* Queued from XTread_socket on FocusIn events.  Translated into
 169      `switch-frame' events in kbd_buffer_get_event, if necessary.  */
 170   FOCUS_IN_EVENT,
 171
 172   /* Generated when mouse moves over window not currently selected.  */
 173   SELECT_WINDOW_EVENT,
 174
 175   /* Queued from XTread_socket when session manager sends
 176      save yourself before shutdown. */
 177   SAVE_SESSION_EVENT
 178
 179 #ifdef HAVE_GPM
 180   , GPM_CLICK_EVENT
 181 #endif
 182
 183 #ifdef HAVE_DBUS
 184   , DBUS_EVENT
 185 #endif
 186
 187 #ifdef WINDOWSNT
 188   /* Generated when an APPCOMMAND event is received, in response to
 189      Multimedia or Internet buttons on some keyboards.
 190      Such keys are available as normal function keys on X through the
 191      Xkeyboard extension.
 192      On Windows, some of them get mapped to normal function key events,
 193      but others need to be handled by APPCOMMAND. Handling them all as
 194      APPCOMMAND events means they can be disabled
 195      (w32-pass-multimedia-buttons-to-system), important on Windows since
 196      the system never sees these keys if Emacs claims to handle them.
 197      On X, the window manager seems to grab the keys it wants
 198      first, so this is not a problem there.  */
 199   , MULTIMEDIA_KEY_EVENT
 200 #endif
 201
 202 #ifdef HAVE_NS
 203   /* Generated when native multi-keystroke input method is used to modify
 204      tentative or indicative text display. */
 205   , NS_TEXT_EVENT
 206   /* Non-key system events (e.g. application menu events) */
 207   , NS_NONKEY_EVENT
 208 #endif
 209
 210 };
 211
 212 /* If a struct input_event has a kind which is SELECTION_REQUEST_EVENT
 213    or SELECTION_CLEAR_EVENT, then its contents are really described
 214    by `struct selection_input_event'; see xterm.h.  */
 215
 216 /* The keyboard input buffer is an array of these structures.  Each one
 217    represents some sort of input event - a keystroke, a mouse click, or
 218    a window system event.  These get turned into their lispy forms when
 219    they are removed from the event queue.  */
 220
 221 struct input_event
 222 {
 223   /* What kind of event was this?  */
 224   enum event_kind kind;
 225
 226   /* For an ASCII_KEYSTROKE_EVENT and MULTIBYTE_CHAR_KEYSTROKE_EVENT,
 227      this is the character.
 228      For a NON_ASCII_KEYSTROKE_EVENT, this is the keysym code.
 229      For a mouse event, this is the button number.  */
 230   /* In WindowsNT, for a mouse wheel event, this is the delta.  */
 231   int code;
 232   enum scroll_bar_part part;
 233
 234   int modifiers;                /* See enum below for interpretation.  */
 235
 236   Lisp_Object x, y;
 237   unsigned long timestamp;
 238
 239   /* This is padding just to put the frame_or_window field
 240      past the size of struct selection_input_event.  */
 241   int *padding[2];
 242
 243   /* This field is copied into a vector while the event is in the queue,
 244      so that garbage collections won't kill it.  */
 245   /* In a menu_bar_event, this is a cons cell whose car is the frame
 246      and whose cdr is the Lisp object that is the event's value.  */
 247   /* This field is last so that struct selection_input_event
 248      does not overlap with it.  */
 249   Lisp_Object frame_or_window;
 250
 251   /* Additional event argument.  This is used for TOOL_BAR_EVENTs and
 252      HELP_EVENTs and avoids calling Fcons during signal handling.  */
 253   Lisp_Object arg;
 254 };
 255
 256 #define EVENT_INIT(event) bzero (&(event), sizeof (struct input_event))
 257
 258 /* Bits in the modifiers member of the input_event structure.
 259    Note that reorder_modifiers assumes that the bits are in canonical
 260    order.
 261
 262    The modifiers applied to mouse clicks are rather ornate.  The
 263    window-system-specific code should store mouse clicks with
 264    up_modifier or down_modifier set.  Having an explicit down modifier
 265    simplifies some of window-system-independent code; without it, the
 266    code would have to recognize down events by checking if the event
 267    is a mouse click lacking the click and drag modifiers.
 268
 269    The window-system independent code turns all up_modifier events
 270    bits into drag_modifier, click_modifier, double_modifier, or
 271    triple_modifier events.  The click_modifier has no written
 272    representation in the names of the symbols used as event heads,
 273    but it does appear in the Qevent_symbol_components property of the
 274    event heads.  */
 275 enum {
 276   up_modifier   =   1,          /* Only used on mouse buttons - always
 277                                    turned into a click or a drag modifier
 278                                    before lisp code sees the event.  */
 279   down_modifier =   2,          /* Only used on mouse buttons.  */
 280   drag_modifier =   4,          /* This is never used in the event
 281                                    queue; it's only used internally by
 282                                    the window-system-independent code.  */
 283   click_modifier=   8,          /* See drag_modifier.  */
 284   double_modifier= 16,          /* See drag_modifier.  */
 285   triple_modifier= 32,          /* See drag_modifier.  */
 286
 287   /* The next four modifier bits are used also in keyboard events at
 288      the Lisp level.
 289
 290      It's probably not the greatest idea to use the 2^23 bit for any
 291      modifier.  It may or may not be the sign bit, depending on
 292      VALBITS, so using it to represent a modifier key means that
 293      characters thus modified have different integer equivalents
 294      depending on the architecture they're running on.  Oh, and
 295      applying XINT to a character whose 2^23 bit is set sign-extends
 296      it, so you get a bunch of bits in the mask you didn't want.
 297
 298      The CHAR_ macros are defined in lisp.h.  */
 299   alt_modifier  =  CHAR_ALT,    /* Under X, the XK_Alt_[LR] keysyms.  */
 300   super_modifier=  CHAR_SUPER,  /* Under X, the XK_Super_[LR] keysyms.  */
 301   hyper_modifier=  CHAR_HYPER,  /* Under X, the XK_Hyper_[LR] keysyms.  */
 302   shift_modifier=  CHAR_SHIFT,
 303   ctrl_modifier =  CHAR_CTL,
 304   meta_modifier =  CHAR_META    /* Under X, the XK_Meta_[LR] keysyms.  */
 305 };
 306
 307 #ifdef HAVE_GPM
 308 #include <gpm.h>
 309 extern int handle_one_term_event (struct tty_display_info *, Gpm_Event *, struct input_event *);
 310 extern void term_mouse_moveto (int, int);
 311
 312 /* The device for which we have enabled gpm support.  */
 313 extern struct tty_display_info *gpm_tty;
 314 #endif
 315
 316 #endif /* CONSP */
 317
 318 \f
 319 struct ns_display_info;
 320 struct x_display_info;
 321 struct w32_display_info;
 322
 323 /* Terminal-local parameters. */
 324 struct terminal
 325 {
 326   /* The first two fields are really the header of a vector */
 327   /* The terminal code does not refer to them.  */
 328   EMACS_UINT size;
 329   struct Lisp_Vector *vec_next;
 330
 331   /* Parameter alist of this terminal.  */
 332   Lisp_Object param_alist;
 333
 334   /* All fields before `next_terminal' should be Lisp_Object and are traced
 335      by the GC.  All fields afterwards are ignored by the GC.  */
 336
 337   /* Chain of all terminal devices. */
 338   struct terminal *next_terminal;
 339
 340   /* Unique id for this terminal device. */
 341   int id;
 342
 343   /* The number of frames that are on this terminal. */
 344   int reference_count;
 345
 346   /* The type of the terminal device. */
 347   enum output_method type;
 348
 349   /* The name of the terminal device.  Do not use this to uniquely
 350      identify a terminal; the same device may be opened multiple
 351      times. */
 352   char *name;
 353
 354   /* The terminal's keyboard object. */
 355   struct kboard *kboard;
 356
 357 #ifdef HAVE_WINDOW_SYSTEM
 358   /* Cache of images.  */
 359   struct image_cache *image_cache;
 360 #endif /* HAVE_WINDOW_SYSTEM */
 361
 362   /* Device-type dependent data shared amongst all frames on this terminal. */
 363   union display_info
 364   {
 365     struct tty_display_info *tty;     /* termchar.h */
 366     struct x_display_info *x;         /* xterm.h */
 367     struct w32_display_info *w32;     /* w32term.h */
 368     struct ns_display_info *ns;       /* nsterm.h */
 369   } display_info;
 370
 371 \f
 372   /* Coding-system to be used for encoding terminal output.  This
 373      structure contains information of a coding-system specified by
 374      the function `set-terminal-coding-system'.  Also see
 375      `safe_terminal_coding' in coding.h.  */
 376   struct coding_system *terminal_coding;
 377
 378   /* Coding-system of what is sent from terminal keyboard.  This
 379      structure contains information of a coding-system specified by
 380      the function `set-keyboard-coding-system'.  */
 381   struct coding_system *keyboard_coding;
 382
 383   /* Terminal characteristics. */
 384   /* XXX Are these really used on non-termcap displays? */
 385
 386   int must_write_spaces;        /* Nonzero means spaces in the text must
 387                                    actually be output; can't just skip over
 388                                    some columns to leave them blank.  */
 389   int fast_clear_end_of_line;   /* Nonzero means terminal has a `ce' string */
 390
 391   int line_ins_del_ok;          /* Terminal can insert and delete lines */
 392   int char_ins_del_ok;          /* Terminal can insert and delete chars */
 393   int scroll_region_ok;         /* Terminal supports setting the scroll
 394                                    window */
 395   int scroll_region_cost;       /* Cost of setting the scroll window,
 396                                    measured in characters. */
 397   int memory_below_frame;       /* Terminal remembers lines scrolled
 398                                    off bottom */
 399
 400 #if 0  /* These are not used anywhere. */
 401   /* EMACS_INT baud_rate; */    /* Output speed in baud */
 402   int min_padding_speed;        /* Speed below which no padding necessary. */
 403   int dont_calculate_costs;     /* Nonzero means don't bother computing
 404                                    various cost tables; we won't use them. */
 405 #endif
 406
 407 \f
 408   /* Window-based redisplay interface for this device (0 for tty
 409      devices). */
 410   struct redisplay_interface *rif;
 411
 412   /* Frame-based redisplay interface. */
 413
 414   /* Text display hooks.  */
 415
 416   void (*cursor_to_hook) P_ ((struct frame *f, int vpos, int hpos));
 417   void (*raw_cursor_to_hook) P_ ((struct frame *, int, int));
 418
 419   void (*clear_to_end_hook) P_ ((struct frame *));
 420   void (*clear_frame_hook) P_ ((struct frame *));
 421   void (*clear_end_of_line_hook) P_ ((struct frame *, int));
 422
 423   void (*ins_del_lines_hook) P_ ((struct frame *f, int, int));
 424
 425   void (*insert_glyphs_hook) P_ ((struct frame *f, struct glyph *s, int n));
 426   void (*write_glyphs_hook) P_ ((struct frame *f, struct glyph *s, int n));
 427   void (*delete_glyphs_hook) P_ ((struct frame *, int));
 428
 429   void (*ring_bell_hook) P_ ((struct frame *f));
 430
 431   void (*reset_terminal_modes_hook) P_ ((struct terminal *));
 432   void (*set_terminal_modes_hook) P_ ((struct terminal *));
 433
 434   void (*update_begin_hook) P_ ((struct frame *));
 435   void (*update_end_hook) P_ ((struct frame *));
 436   void (*set_terminal_window_hook) P_ ((struct frame *, int));
 437
 438   /* Multi-frame and mouse support hooks.  */
 439
 440   /* Return the current position of the mouse.
 441
 442      Set *f to the frame the mouse is in, or zero if the mouse is in no
 443      Emacs frame.  If it is set to zero, all the other arguments are
 444      garbage.
 445
 446      If the motion started in a scroll bar, set *bar_window to the
 447      scroll bar's window, *part to the part the mouse is currently over,
 448      *x to the position of the mouse along the scroll bar, and *y to the
 449      overall length of the scroll bar.
 450
 451      Otherwise, set *bar_window to Qnil, and *x and *y to the column and
 452      row of the character cell the mouse is over.
 453
 454      Set *time to the time the mouse was at the returned position.
 455
 456      This should clear mouse_moved until the next motion
 457      event arrives.  */
 458   void (*mouse_position_hook) P_ ((struct frame **f, int,
 459                                    Lisp_Object *bar_window,
 460                                    enum scroll_bar_part *part,
 461                                    Lisp_Object *x,
 462                                    Lisp_Object *y,
 463                                    unsigned long *time));
 464
 465   /* The window system handling code should set this if the mouse has
 466      moved since the last call to the mouse_position_hook.  Calling that
 467      hook should clear this.  */
 468   int mouse_moved;
 469
 470   /* When a frame's focus redirection is changed, this hook tells the
 471      window system code to re-decide where to put the highlight.  Under
 472      X, this means that Emacs lies about where the focus is.  */
 473   void (*frame_rehighlight_hook) P_ ((struct frame *));
 474
 475   /* If we're displaying frames using a window system that can stack
 476      frames on top of each other, this hook allows you to bring a frame
 477      to the front, or bury it behind all the other windows.  If this
 478      hook is zero, that means the terminal we're displaying on doesn't
 479      support overlapping frames, so there's no need to raise or lower
 480      anything.
 481
 482      If RAISE is non-zero, F is brought to the front, before all other
 483      windows.  If RAISE is zero, F is sent to the back, behind all other
 484      windows.  */
 485   void (*frame_raise_lower_hook) P_ ((struct frame *f, int raise));
 486
 487   /* If the value of the frame parameter changed, whis hook is called.
 488      For example, if going from fullscreen to not fullscreen this hook
 489      may do something OS dependent, like extended window manager hints on X11.  */
 490   void (*fullscreen_hook) P_ ((struct frame *f));
 491
 492   \f
 493   /* Scroll bar hooks.  */
 494
 495   /* The representation of scroll bars is determined by the code which
 496      implements them, except for one thing: they must be represented by
 497      lisp objects.  This allows us to place references to them in
 498      Lisp_Windows without worrying about those references becoming
 499      dangling references when the scroll bar is destroyed.
 500
 501      The window-system-independent portion of Emacs just refers to
 502      scroll bars via their windows, and never looks inside the scroll bar
 503      representation; it always uses hook functions to do all the
 504      scroll bar manipulation it needs.
 505
 506      The `vertical_scroll_bar' field of a Lisp_Window refers to that
 507      window's scroll bar, or is nil if the window doesn't have a
 508      scroll bar.
 509
 510      The `scroll_bars' and `condemned_scroll_bars' fields of a Lisp_Frame
 511      are free for use by the scroll bar implementation in any way it sees
 512      fit.  They are marked by the garbage collector.  */
 513
 514
 515   /* Set the vertical scroll bar for WINDOW to have its upper left corner
 516      at (TOP, LEFT), and be LENGTH rows high.  Set its handle to
 517      indicate that we are displaying PORTION characters out of a total
 518      of WHOLE characters, starting at POSITION.  If WINDOW doesn't yet
 519      have a scroll bar, create one for it.  */
 520   void (*set_vertical_scroll_bar_hook) P_ ((struct window *window,
 521                                             int portion, int whole,
 522                                             int position));
 523
 524
 525   /* The following three hooks are used when we're doing a thorough
 526      redisplay of the frame.  We don't explicitly know which scroll bars
 527      are going to be deleted, because keeping track of when windows go
 528      away is a real pain - can you say set-window-configuration?
 529      Instead, we just assert at the beginning of redisplay that *all*
 530      scroll bars are to be removed, and then save scroll bars from the
 531      fiery pit when we actually redisplay their window.  */
 532
 533   /* Arrange for all scroll bars on FRAME to be removed at the next call
 534      to `*judge_scroll_bars_hook'.  A scroll bar may be spared if
 535      `*redeem_scroll_bar_hook' is applied to its window before the judgement.
 536
 537      This should be applied to each frame each time its window tree is
 538      redisplayed, even if it is not displaying scroll bars at the moment;
 539      if the HAS_SCROLL_BARS flag has just been turned off, only calling
 540      this and the judge_scroll_bars_hook will get rid of them.
 541
 542      If non-zero, this hook should be safe to apply to any frame,
 543      whether or not it can support scroll bars, and whether or not it is
 544      currently displaying them.  */
 545   void (*condemn_scroll_bars_hook) P_ ((struct frame *frame));
 546
 547   /* Unmark WINDOW's scroll bar for deletion in this judgement cycle.
 548      Note that it's okay to redeem a scroll bar that is not condemned.  */
 549   void (*redeem_scroll_bar_hook) P_ ((struct window *window));
 550
 551   /* Remove all scroll bars on FRAME that haven't been saved since the
 552      last call to `*condemn_scroll_bars_hook'.
 553
 554      This should be applied to each frame after each time its window
 555      tree is redisplayed, even if it is not displaying scroll bars at the
 556      moment; if the HAS_SCROLL_BARS flag has just been turned off, only
 557      calling this and condemn_scroll_bars_hook will get rid of them.
 558
 559      If non-zero, this hook should be safe to apply to any frame,
 560      whether or not it can support scroll bars, and whether or not it is
 561      currently displaying them.  */
 562   void (*judge_scroll_bars_hook) P_ ((struct frame *FRAME));
 563
 564 \f
 565   /* Called to read input events.
 566
 567      TERMINAL indicates which terminal device to read from.  Input
 568      events should be read into BUF, the size of which is given in
 569      SIZE.  EXPECTED is non-zero if the caller suspects that new input
 570      is available.
 571
 572      A positive return value indicates that that many input events
 573      where read into BUF.
 574      Zero means no events were immediately available.
 575      A value of -1 means a transient read error, while -2 indicates
 576      that the device was closed (hangup), and it should be deleted.
 577
 578      XXX Please note that a non-zero value of EXPECTED only means that
 579      there is available input on at least one of the currently opened
 580      terminal devices -- but not necessarily on this device.
 581      Therefore, in most cases EXPECTED should be simply ignored.
 582
 583      XXX This documentation needs to be updated.  */
 584   int (*read_socket_hook) P_ ((struct terminal *terminal,
 585                                int expected,
 586                                struct input_event *hold_quit));
 587
 588   /* Called when a frame's display becomes entirely up to date.  */
 589   void (*frame_up_to_date_hook) P_ ((struct frame *));
 590
 591 \f
 592   /* Called to delete the device-specific portions of a frame that is
 593      on this terminal device. */
 594   void (*delete_frame_hook) P_ ((struct frame *));
 595
 596   /* Called after the last frame on this terminal is deleted, or when
 597      the display device was closed (hangup).
 598
 599      If this is NULL, then the generic delete_terminal is called
 600      instead.  Otherwise the hook must call delete_terminal itself.
 601
 602      The hook must check for and close any live frames that are still
 603      on the terminal.  delete_frame ensures that there are no live
 604      frames on the terminal when it calls this hook, so infinite
 605      recursion is prevented.  */
 606   void (*delete_terminal_hook) P_ ((struct terminal *));
 607 };
 608
 609
 610 /* Chain of all terminal devices currently in use. */
 611 extern struct terminal *terminal_list;
 612
 613 #define FRAME_MUST_WRITE_SPACES(f) ((f)->terminal->must_write_spaces)
 614 #define FRAME_FAST_CLEAR_END_OF_LINE(f) ((f)->terminal->fast_clear_end_of_line)
 615 #define FRAME_LINE_INS_DEL_OK(f) ((f)->terminal->line_ins_del_ok)
 616 #define FRAME_CHAR_INS_DEL_OK(f) ((f)->terminal->char_ins_del_ok)
 617 #define FRAME_SCROLL_REGION_OK(f) ((f)->terminal->scroll_region_ok)
 618 #define FRAME_SCROLL_REGION_COST(f) ((f)->terminal->scroll_region_cost)
 619 #define FRAME_MEMORY_BELOW_FRAME(f) ((f)->terminal->memory_below_frame)
 620
 621 #define FRAME_TERMINAL_CODING(f) ((f)->terminal->terminal_coding)
 622 #define FRAME_KEYBOARD_CODING(f) ((f)->terminal->keyboard_coding)
 623
 624 #define TERMINAL_TERMINAL_CODING(d) ((d)->terminal_coding)
 625 #define TERMINAL_KEYBOARD_CODING(d) ((d)->keyboard_coding)
 626
 627 #define FRAME_RIF(f) ((f)->terminal->rif)
 628
 629 #define FRAME_TERMINAL(f) ((f)->terminal)
 630
 631 /* FRAME_WINDOW_P tests whether the frame is a window, and is
 632    defined to be the predicate for the window system being used.  */
 633
 634 #ifdef HAVE_X_WINDOWS
 635 #define FRAME_WINDOW_P(f) FRAME_X_P (f)
 636 #endif
 637 #ifdef HAVE_NTGUI
 638 #define FRAME_WINDOW_P(f) FRAME_W32_P (f)
 639 #endif
 640 #ifndef FRAME_WINDOW_P
 641 #define FRAME_WINDOW_P(f) (0)
 642 #endif
 643
 644 /* Return true if the terminal device is not suspended. */
 645 #define TERMINAL_ACTIVE_P(d) (((d)->type != output_termcap && (d)->type !=output_msdos_raw) || (d)->display_info.tty->input)
 646
 647 extern Lisp_Object get_terminal_param P_ ((struct terminal *, Lisp_Object));
 648 extern struct terminal *get_terminal P_ ((Lisp_Object terminal, int));
 649 extern struct terminal *create_terminal P_ ((void));
 650 extern void delete_terminal P_ ((struct terminal *));
 651
 652 /* The initial terminal device, created by initial_term_init. */
 653 extern struct terminal *initial_terminal;
 654
 655 #ifdef HAVE_GPM
 656 extern void close_gpm (int gpm_fd);
 657 #endif
 658
 659 /* arch-tag: 33a00ecc-52b5-4186-a410-8801ac9f087d
 660    (do not change this comment) */