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  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, or (at your option)
  10 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; see the file COPYING.  If not, write to
  19 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  20 Boston, MA 02110-1301, USA.  */
  21
  22 \f
  23 /* Miscellanea.   */
  24
  25 struct glyph;
  26 struct frame;
  27 \f
  28
  29 enum scroll_bar_part {
  30   scroll_bar_above_handle,
  31   scroll_bar_handle,
  32   scroll_bar_below_handle,
  33   scroll_bar_up_arrow,
  34   scroll_bar_down_arrow,
  35   scroll_bar_to_top,
  36   scroll_bar_to_bottom,
  37   scroll_bar_end_scroll,
  38   scroll_bar_move_ratio
  39 };
  40
  41 /* If the value of the frame parameter changed, whis hook is called.
  42    For example, if going from fullscreen to not fullscreen this hook
  43    may do something OS dependent, like extended window manager hints on X11.  */
  44 extern void (*fullscreen_hook) P_ ((struct frame *f));
  45
  46 \f
  47 /* Input queue declarations and hooks.  */
  48
  49 /* Expedient hack: only provide the below definitions to files that
  50    are prepared to handle lispy things.  CONSP is defined if lisp.h
  51    has been included before this file.  */
  52 #ifdef CONSP
  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 #if defined (WINDOWSNT) || defined (MAC_OS)
 111   LANGUAGE_CHANGE_EVENT,        /* A LANGUAGE_CHANGE_EVENT is
 112                                    generated on WINDOWSNT or 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 MAC_OS
 182   /* Generated when an Apple event, a HICommand event, or a Services
 183      menu event is received and the corresponding handler is
 184      registered.  Members `x' and `y' are for the event class and ID
 185      symbols, respectively.  Member `arg' is a Lisp object converted
 186      from the received Apple event.  Parameters for non-Apple events
 187      are converted to those in Apple events.  */
 188   , MAC_APPLE_EVENT
 189 #endif
 190
 191 #ifdef HAVE_GPM
 192   , GPM_CLICK_EVENT
 193 #endif
 194
 195 #ifdef HAVE_DBUS
 196   , DBUS_EVENT
 197 #endif
 198
 199 #ifdef WINDOWSNT
 200   /* Generated when an APPCOMMAND event is received, in response to
 201      Multimedia or Internet buttons on some keyboards.
 202      Such keys are available as normal function keys on X through the
 203      Xkeyboard extension.
 204      On Windows, some of them get mapped to normal function key events,
 205      but others need to be handled by APPCOMMAND. Handling them all as
 206      APPCOMMAND events means they can be disabled
 207      (w32-pass-multimedia-buttons-to-system), important on Windows since
 208      the system never sees these keys if Emacs claims to handle them.
 209      On X, the window manager seems to grab the keys it wants
 210      first, so this is not a problem there.  */
 211   , MULTIMEDIA_KEY_EVENT
 212 #endif
 213 };
 214
 215 /* If a struct input_event has a kind which is SELECTION_REQUEST_EVENT
 216    or SELECTION_CLEAR_EVENT, then its contents are really described
 217    by `struct selection_input_event'; see xterm.h.  */
 218
 219 /* The keyboard input buffer is an array of these structures.  Each one
 220    represents some sort of input event - a keystroke, a mouse click, or
 221    a window system event.  These get turned into their lispy forms when
 222    they are removed from the event queue.  */
 223
 224 struct input_event
 225 {
 226   /* What kind of event was this?  */
 227   enum event_kind kind;
 228
 229   /* For an ASCII_KEYSTROKE_EVENT and MULTIBYTE_CHAR_KEYSTROKE_EVENT,
 230      this is the character.
 231      For a NON_ASCII_KEYSTROKE_EVENT, this is the keysym code.
 232      For a mouse event, this is the button number.  */
 233   /* In WindowsNT, for a mouse wheel event, this is the delta.  */
 234   int code;
 235   enum scroll_bar_part part;
 236
 237   int modifiers;                /* See enum below for interpretation.  */
 238
 239   Lisp_Object x, y;
 240   unsigned long timestamp;
 241
 242   /* This is padding just to put the frame_or_window field
 243      past the size of struct selection_input_event.  */
 244   int *padding[2];
 245
 246   /* This field is copied into a vector while the event is in the queue,
 247      so that garbage collections won't kill it.  */
 248   /* In a menu_bar_event, this is a cons cell whose car is the frame
 249      and whose cdr is the Lisp object that is the event's value.  */
 250   /* This field is last so that struct selection_input_event
 251      does not overlap with it.  */
 252   Lisp_Object frame_or_window;
 253
 254   /* Additional event argument.  This is used for TOOL_BAR_EVENTs and
 255      HELP_EVENTs and avoids calling Fcons during signal handling.  */
 256   Lisp_Object arg;
 257 };
 258
 259 #define EVENT_INIT(event) bzero (&(event), sizeof (struct input_event))
 260
 261 /* Bits in the modifiers member of the input_event structure.
 262    Note that reorder_modifiers assumes that the bits are in canonical
 263    order.
 264
 265    The modifiers applied to mouse clicks are rather ornate.  The
 266    window-system-specific code should store mouse clicks with
 267    up_modifier or down_modifier set.  Having an explicit down modifier
 268    simplifies some of window-system-independent code; without it, the
 269    code would have to recognize down events by checking if the event
 270    is a mouse click lacking the click and drag modifiers.
 271
 272    The window-system independent code turns all up_modifier events
 273    bits into drag_modifier, click_modifier, double_modifier, or
 274    triple_modifier events.  The click_modifier has no written
 275    representation in the names of the symbols used as event heads,
 276    but it does appear in the Qevent_symbol_components property of the
 277    event heads.  */
 278 enum {
 279   up_modifier   =   1,          /* Only used on mouse buttons - always
 280                                    turned into a click or a drag modifier
 281                                    before lisp code sees the event.  */
 282   down_modifier =   2,          /* Only used on mouse buttons.  */
 283   drag_modifier =   4,          /* This is never used in the event
 284                                    queue; it's only used internally by
 285                                    the window-system-independent code.  */
 286   click_modifier=   8,          /* See drag_modifier.  */
 287   double_modifier= 16,          /* See drag_modifier.  */
 288   triple_modifier= 32,          /* See drag_modifier.  */
 289
 290   /* The next four modifier bits are used also in keyboard events at
 291      the Lisp level.
 292
 293      It's probably not the greatest idea to use the 2^23 bit for any
 294      modifier.  It may or may not be the sign bit, depending on
 295      VALBITS, so using it to represent a modifier key means that
 296      characters thus modified have different integer equivalents
 297      depending on the architecture they're running on.  Oh, and
 298      applying XINT to a character whose 2^23 bit is set sign-extends
 299      it, so you get a bunch of bits in the mask you didn't want.
 300
 301      The CHAR_ macros are defined in lisp.h.  */
 302   alt_modifier  =  CHAR_ALT,    /* Under X, the XK_Alt_[LR] keysyms.  */
 303   super_modifier=  CHAR_SUPER,  /* Under X, the XK_Super_[LR] keysyms.  */
 304   hyper_modifier=  CHAR_HYPER,  /* Under X, the XK_Hyper_[LR] keysyms.  */
 305   shift_modifier=  CHAR_SHIFT,
 306   ctrl_modifier =  CHAR_CTL,
 307   meta_modifier =  CHAR_META    /* Under X, the XK_Meta_[LR] keysyms.  */
 308 };
 309
 310 #ifdef HAVE_GPM
 311 #include <gpm.h>
 312 extern int handle_one_term_event (struct tty_display_info *, Gpm_Event *, struct input_event *);
 313 extern void term_mouse_moveto (int, int);
 314
 315 /* The device for which we have enabled gpm support.  */
 316 extern struct tty_display_info *gpm_tty;
 317 #endif
 318
 319 #endif /* CONSP */
 320
 321 \f
 322 struct mac_display_info;
 323 struct w32_display_info;
 324
 325 /* Terminal-local parameters. */
 326 struct terminal
 327 {
 328   /* The first two fields are really the header of a vector */
 329   /* The terminal code does not refer to them.  */
 330   EMACS_UINT size;
 331   struct Lisp_Vector *vec_next;
 332
 333   /* Parameter alist of this terminal.  */
 334   Lisp_Object param_alist;
 335
 336   /* All fields before `next_terminal' should be Lisp_Object and are traced
 337      by the GC.  All fields afterwards are ignored by the GC.  */
 338
 339   /* Chain of all terminal devices. */
 340   struct terminal *next_terminal;
 341
 342   /* Unique id for this terminal device. */
 343   int id;
 344
 345   /* The number of frames that are on this terminal. */
 346   int reference_count;
 347
 348   /* The type of the terminal device. */
 349   enum output_method type;
 350
 351   /* The name of the terminal device.  Do not use this to uniquely
 352      identify a terminal; the same device may be opened multiple
 353      times. */
 354   char *name;
 355
 356 #ifdef MULTI_KBOARD
 357   /* The terminal's keyboard object. */
 358   struct kboard *kboard;
 359 #endif
 360
 361 #ifdef HAVE_WINDOW_SYSTEM
 362   /* Cache of images.  */
 363   struct image_cache *image_cache;
 364 #endif /* HAVE_WINDOW_SYSTEM */
 365
 366   /* Device-type dependent data shared amongst all frames on this terminal. */
 367   union display_info
 368   {
 369     struct tty_display_info *tty;     /* termchar.h */
 370     struct x_display_info *x;         /* xterm.h */
 371     struct w32_display_info *w32;     /* w32term.h */
 372     struct mac_display_info *mac;     /* macterm.h */
 373   } display_info;
 374
 375 \f
 376   /* Coding-system to be used for encoding terminal output.  This
 377      structure contains information of a coding-system specified by
 378      the function `set-terminal-coding-system'.  Also see
 379      `safe_terminal_coding' in coding.h.  */
 380   struct coding_system *terminal_coding;
 381
 382   /* Coding-system of what is sent from terminal keyboard.  This
 383      structure contains information of a coding-system specified by
 384      the function `set-keyboard-coding-system'.  */
 385   struct coding_system *keyboard_coding;
 386
 387   /* Terminal characteristics. */
 388   /* XXX Are these really used on non-termcap displays? */
 389
 390   int must_write_spaces;        /* Nonzero means spaces in the text must
 391                                    actually be output; can't just skip over
 392                                    some columns to leave them blank.  */
 393   int fast_clear_end_of_line;   /* Nonzero means terminal has a `ce' string */
 394
 395   int line_ins_del_ok;          /* Terminal can insert and delete lines */
 396   int char_ins_del_ok;          /* Terminal can insert and delete chars */
 397   int scroll_region_ok;         /* Terminal supports setting the scroll
 398                                    window */
 399   int scroll_region_cost;       /* Cost of setting the scroll window,
 400                                    measured in characters. */
 401   int memory_below_frame;       /* Terminal remembers lines scrolled
 402                                    off bottom */
 403
 404 #if 0  /* These are not used anywhere. */
 405   /* EMACS_INT baud_rate; */    /* Output speed in baud */
 406   int min_padding_speed;        /* Speed below which no padding necessary. */
 407   int dont_calculate_costs;     /* Nonzero means don't bother computing
 408                                    various cost tables; we won't use them. */
 409 #endif
 410
 411 \f
 412   /* Window-based redisplay interface for this device (0 for tty
 413      devices). */
 414   struct redisplay_interface *rif;
 415
 416   /* Frame-based redisplay interface. */
 417
 418   /* Text display hooks.  */
 419
 420   void (*cursor_to_hook) P_ ((struct frame *f, int vpos, int hpos));
 421   void (*raw_cursor_to_hook) P_ ((struct frame *, int, int));
 422
 423   void (*clear_to_end_hook) P_ ((struct frame *));
 424   void (*clear_frame_hook) P_ ((struct frame *));
 425   void (*clear_end_of_line_hook) P_ ((struct frame *, int));
 426
 427   void (*ins_del_lines_hook) P_ ((struct frame *f, int, int));
 428
 429   void (*insert_glyphs_hook) P_ ((struct frame *f, struct glyph *s, int n));
 430   void (*write_glyphs_hook) P_ ((struct frame *f, struct glyph *s, int n));
 431   void (*delete_glyphs_hook) P_ ((struct frame *, int));
 432
 433   void (*ring_bell_hook) P_ ((struct frame *f));
 434
 435   void (*reset_terminal_modes_hook) P_ ((struct terminal *));
 436   void (*set_terminal_modes_hook) P_ ((struct terminal *));
 437
 438   void (*update_begin_hook) P_ ((struct frame *));
 439   void (*update_end_hook) P_ ((struct frame *));
 440   void (*set_terminal_window_hook) P_ ((struct frame *, int));
 441
 442   /* Multi-frame and mouse support hooks.  */
 443
 444   /* Return the current position of the mouse.
 445
 446      Set *f to the frame the mouse is in, or zero if the mouse is in no
 447      Emacs frame.  If it is set to zero, all the other arguments are
 448      garbage.
 449
 450      If the motion started in a scroll bar, set *bar_window to the
 451      scroll bar's window, *part to the part the mouse is currently over,
 452      *x to the position of the mouse along the scroll bar, and *y to the
 453      overall length of the scroll bar.
 454
 455      Otherwise, set *bar_window to Qnil, and *x and *y to the column and
 456      row of the character cell the mouse is over.
 457
 458      Set *time to the time the mouse was at the returned position.
 459
 460      This should clear mouse_moved until the next motion
 461      event arrives.  */
 462   void (*mouse_position_hook) P_ ((struct frame **f, int,
 463                                    Lisp_Object *bar_window,
 464                                    enum scroll_bar_part *part,
 465                                    Lisp_Object *x,
 466                                    Lisp_Object *y,
 467                                    unsigned long *time));
 468
 469   /* The window system handling code should set this if the mouse has
 470      moved since the last call to the mouse_position_hook.  Calling that
 471      hook should clear this.  */
 472   int mouse_moved;
 473
 474   /* When a frame's focus redirection is changed, this hook tells the
 475      window system code to re-decide where to put the highlight.  Under
 476      X, this means that Emacs lies about where the focus is.  */
 477   void (*frame_rehighlight_hook) P_ ((struct frame *));
 478
 479   /* If we're displaying frames using a window system that can stack
 480      frames on top of each other, this hook allows you to bring a frame
 481      to the front, or bury it behind all the other windows.  If this
 482      hook is zero, that means the terminal we're displaying on doesn't
 483      support overlapping frames, so there's no need to raise or lower
 484      anything.
 485
 486      If RAISE is non-zero, F is brought to the front, before all other
 487      windows.  If RAISE is zero, F is sent to the back, behind all other
 488      windows.  */
 489   void (*frame_raise_lower_hook) P_ ((struct frame *f, int raise));
 490
 491   /* If the value of the frame parameter changed, whis hook is called.
 492      For example, if going from fullscreen to not fullscreen this hook
 493      may do something OS dependent, like extended window manager hints on X11.  */
 494   void (*fullscreen_hook) P_ ((struct frame *f));
 495
 496   \f
 497   /* Scroll bar hooks.  */
 498
 499   /* The representation of scroll bars is determined by the code which
 500      implements them, except for one thing: they must be represented by
 501      lisp objects.  This allows us to place references to them in
 502      Lisp_Windows without worrying about those references becoming
 503      dangling references when the scroll bar is destroyed.
 504
 505      The window-system-independent portion of Emacs just refers to
 506      scroll bars via their windows, and never looks inside the scroll bar
 507      representation; it always uses hook functions to do all the
 508      scroll bar manipulation it needs.
 509
 510      The `vertical_scroll_bar' field of a Lisp_Window refers to that
 511      window's scroll bar, or is nil if the window doesn't have a
 512      scroll bar.
 513
 514      The `scroll_bars' and `condemned_scroll_bars' fields of a Lisp_Frame
 515      are free for use by the scroll bar implementation in any way it sees
 516      fit.  They are marked by the garbage collector.  */
 517
 518
 519   /* Set the vertical scroll bar for WINDOW to have its upper left corner
 520      at (TOP, LEFT), and be LENGTH rows high.  Set its handle to
 521      indicate that we are displaying PORTION characters out of a total
 522      of WHOLE characters, starting at POSITION.  If WINDOW doesn't yet
 523      have a scroll bar, create one for it.  */
 524   void (*set_vertical_scroll_bar_hook) P_ ((struct window *window,
 525                                             int portion, int whole,
 526                                             int position));
 527
 528
 529   /* The following three hooks are used when we're doing a thorough
 530      redisplay of the frame.  We don't explicitly know which scroll bars
 531      are going to be deleted, because keeping track of when windows go
 532      away is a real pain - can you say set-window-configuration?
 533      Instead, we just assert at the beginning of redisplay that *all*
 534      scroll bars are to be removed, and then save scroll bars from the
 535      fiery pit when we actually redisplay their window.  */
 536
 537   /* Arrange for all scroll bars on FRAME to be removed at the next call
 538      to `*judge_scroll_bars_hook'.  A scroll bar may be spared if
 539      `*redeem_scroll_bar_hook' is applied to its window before the judgement.
 540
 541      This should be applied to each frame each time its window tree is
 542      redisplayed, even if it is not displaying scroll bars at the moment;
 543      if the HAS_SCROLL_BARS flag has just been turned off, only calling
 544      this and the judge_scroll_bars_hook will get rid of them.
 545
 546      If non-zero, this hook should be safe to apply to any frame,
 547      whether or not it can support scroll bars, and whether or not it is
 548      currently displaying them.  */
 549   void (*condemn_scroll_bars_hook) P_ ((struct frame *frame));
 550
 551   /* Unmark WINDOW's scroll bar for deletion in this judgement cycle.
 552      Note that it's okay to redeem a scroll bar that is not condemned.  */
 553   void (*redeem_scroll_bar_hook) P_ ((struct window *window));
 554
 555   /* Remove all scroll bars on FRAME that haven't been saved since the
 556      last call to `*condemn_scroll_bars_hook'.
 557
 558      This should be applied to each frame after each time its window
 559      tree is redisplayed, even if it is not displaying scroll bars at the
 560      moment; if the HAS_SCROLL_BARS flag has just been turned off, only
 561      calling this and condemn_scroll_bars_hook will get rid of them.
 562
 563      If non-zero, this hook should be safe to apply to any frame,
 564      whether or not it can support scroll bars, and whether or not it is
 565      currently displaying them.  */
 566   void (*judge_scroll_bars_hook) P_ ((struct frame *FRAME));
 567
 568 \f
 569   /* Called to read input events.
 570
 571      TERMINAL indicates which terminal device to read from.  Input
 572      events should be read into BUF, the size of which is given in
 573      SIZE.  EXPECTED is non-zero if the caller suspects that new input
 574      is available.
 575
 576      A positive return value indicates that that many input events
 577      where read into BUF.
 578      Zero means no events were immediately available.
 579      A value of -1 means a transient read error, while -2 indicates
 580      that the device was closed (hangup), and it should be deleted.
 581
 582      XXX Please note that a non-zero value of EXPECTED only means that
 583      there is available input on at least one of the currently opened
 584      terminal devices -- but not necessarily on this device.
 585      Therefore, in most cases EXPECTED should be simply ignored.
 586
 587      XXX This documentation needs to be updated.  */
 588   int (*read_socket_hook) P_ ((struct terminal *terminal,
 589                                int expected,
 590                                struct input_event *hold_quit));
 591
 592   /* Called when a frame's display becomes entirely up to date.  */
 593   void (*frame_up_to_date_hook) P_ ((struct frame *));
 594
 595 \f
 596   /* Called to delete the device-specific portions of a frame that is
 597      on this terminal device. */
 598   void (*delete_frame_hook) P_ ((struct frame *));
 599
 600   /* Called after the last frame on this terminal is deleted, or when
 601      the display device was closed (hangup).
 602
 603      If this is NULL, then the generic delete_terminal is called
 604      instead.  Otherwise the hook must call delete_terminal itself.
 605
 606      The hook must check for and close any live frames that are still
 607      on the terminal.  Fdelete_frame ensures that there are no live
 608      frames on the terminal when it calls this hook, so infinite
 609      recursion is prevented.  */
 610   void (*delete_terminal_hook) P_ ((struct terminal *));
 611 };
 612
 613
 614 /* Chain of all terminal devices currently in use. */
 615 extern struct terminal *terminal_list;
 616
 617 #define FRAME_MUST_WRITE_SPACES(f) ((f)->terminal->must_write_spaces)
 618 #define FRAME_FAST_CLEAR_END_OF_LINE(f) ((f)->terminal->fast_clear_end_of_line)
 619 #define FRAME_LINE_INS_DEL_OK(f) ((f)->terminal->line_ins_del_ok)
 620 #define FRAME_CHAR_INS_DEL_OK(f) ((f)->terminal->char_ins_del_ok)
 621 #define FRAME_SCROLL_REGION_OK(f) ((f)->terminal->scroll_region_ok)
 622 #define FRAME_SCROLL_REGION_COST(f) ((f)->terminal->scroll_region_cost)
 623 #define FRAME_MEMORY_BELOW_FRAME(f) ((f)->terminal->memory_below_frame)
 624
 625 #define FRAME_TERMINAL_CODING(f) ((f)->terminal->terminal_coding)
 626 #define FRAME_KEYBOARD_CODING(f) ((f)->terminal->keyboard_coding)
 627
 628 #define TERMINAL_TERMINAL_CODING(d) ((d)->terminal_coding)
 629 #define TERMINAL_KEYBOARD_CODING(d) ((d)->keyboard_coding)
 630
 631 #define FRAME_RIF(f) ((f)->terminal->rif)
 632
 633 #define FRAME_TERMINAL(f) ((f)->terminal)
 634
 635 /* FRAME_WINDOW_P tests whether the frame is a window, and is
 636    defined to be the predicate for the window system being used.  */
 637
 638 #ifdef HAVE_X_WINDOWS
 639 #define FRAME_WINDOW_P(f) FRAME_X_P (f)
 640 #endif
 641 #ifdef HAVE_NTGUI
 642 #define FRAME_WINDOW_P(f) FRAME_W32_P (f)
 643 #endif
 644 #ifdef MAC_OS
 645 #define FRAME_WINDOW_P(f) FRAME_MAC_P (f)
 646 #endif
 647 #ifndef FRAME_WINDOW_P
 648 #define FRAME_WINDOW_P(f) (0)
 649 #endif
 650
 651 /* Return true if the terminal device is not suspended. */
 652 #define TERMINAL_ACTIVE_P(d) ((d)->type != output_termcap || (d)->display_info.tty->input)
 653
 654 extern Lisp_Object get_terminal_param P_ ((struct terminal *, Lisp_Object));
 655 extern struct terminal *get_terminal P_ ((Lisp_Object terminal, int));
 656 extern struct terminal *create_terminal P_ ((void));
 657 extern void delete_terminal P_ ((struct terminal *));
 658
 659 /* The initial terminal device, created by initial_term_init. */
 660 extern struct terminal *initial_terminal;
 661
 662 /* arch-tag: 33a00ecc-52b5-4186-a410-8801ac9f087d
 663    (do not change this comment) */