src/termhooks.h

   1 /* Parameters and display hooks for terminal devices.
   2
   3 Copyright (C) 1985-1986, 1993-1994, 2001-2013 Free Software Foundation,
   4 Inc.
   5
   6 This file is part of GNU Emacs.
   7
   8 GNU Emacs is free software: you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation, either version 3 of the License, or
  11 (at your option) any later version.
  12
  13 GNU Emacs is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 \f
  22 /* Miscellanea.   */
  23
  24 #include "systime.h" /* for Time */
  25
  26 INLINE_HEADER_BEGIN
  27 #ifndef TERMHOOKS_INLINE
  28 # define TERMHOOKS_INLINE INLINE
  29 #endif
  30
  31 struct glyph;
  32 struct frame;
  33 \f
  34
  35 enum scroll_bar_part {
  36   scroll_bar_above_handle,
  37   scroll_bar_handle,
  38   scroll_bar_below_handle,
  39   scroll_bar_up_arrow,
  40   scroll_bar_down_arrow,
  41   scroll_bar_to_top,
  42   scroll_bar_to_bottom,
  43   scroll_bar_end_scroll,
  44   scroll_bar_move_ratio
  45 };
  46
  47 /* If the value of the frame parameter changed, whis hook is called.
  48    For example, if going from fullscreen to not fullscreen this hook
  49    may do something OS dependent, like extended window manager hints on X11.  */
  50 extern void (*fullscreen_hook) (struct frame *f);
  51
  52 \f
  53 /* Input queue declarations and hooks.  */
  54
  55 enum event_kind
  56 {
  57   NO_EVENT,                     /* nothing happened.  This should never
  58                                    actually appear in the event queue.  */
  59
  60   ASCII_KEYSTROKE_EVENT,        /* The ASCII code is in .code, perhaps
  61                                    with modifiers applied.
  62                                    .modifiers holds the state of the
  63                                    modifier keys.
  64                                    .frame_or_window is the frame in
  65                                    which the key was typed.
  66                                    .timestamp gives a timestamp (in
  67                                    milliseconds) for the keystroke.  */
  68   MULTIBYTE_CHAR_KEYSTROKE_EVENT,       /* The multibyte char code is in .code,
  69                                    perhaps with modifiers applied.
  70                                    The others are the same as
  71                                    ASCII_KEYSTROKE_EVENT.  */
  72   NON_ASCII_KEYSTROKE_EVENT,    /* .code is a number identifying the
  73                                    function key.  A code N represents
  74                                    a key whose name is
  75                                    function_key_names[N]; function_key_names
  76                                    is a table in keyboard.c to which you
  77                                    should feel free to add missing keys.
  78                                    .modifiers holds the state of the
  79                                    modifier keys.
  80                                    .frame_or_window is the frame in
  81                                    which the key was typed.
  82                                    .timestamp gives a timestamp (in
  83                                    milliseconds) for the keystroke.  */
  84   TIMER_EVENT,                  /* A timer fired.  */
  85   MOUSE_CLICK_EVENT,            /* The button number is in .code; it must
  86                                    be >= 0 and < NUM_MOUSE_BUTTONS, defined
  87                                    below.
  88                                    .modifiers holds the state of the
  89                                    modifier keys.
  90                                    .x and .y give the mouse position,
  91                                    in characters, within the window.
  92                                    .frame_or_window gives the frame
  93                                    the mouse click occurred in.
  94                                    .timestamp gives a timestamp (in
  95                                    milliseconds) for the click.  */
  96   WHEEL_EVENT,                  /* A wheel event is generated by a
  97                                    wheel on a mouse (e.g., MS
  98                                    Intellimouse).
  99                                    .modifiers holds the rotate
 100                                    direction (up or down), and the
 101                                    state of the modifier keys.
 102                                    .x and .y give the mouse position,
 103                                    in characters, within the window.
 104                                    .frame_or_window gives the frame
 105                                    the wheel event occurred in.
 106                                    .timestamp gives a timestamp (in
 107                                    milliseconds) for the event.  */
 108   HORIZ_WHEEL_EVENT,            /* A wheel event generated by a second
 109                                    horizontal wheel that is present on some
 110                                    mice. See WHEEL_EVENT.  */
 111 #ifdef HAVE_NTGUI
 112   LANGUAGE_CHANGE_EVENT,        /* A LANGUAGE_CHANGE_EVENT is
 113                                    generated when HAVE_NTGUI or on Mac OS
 114                                    when the keyboard layout or input
 115                                    language is changed by the
 116                                    user.  */
 117 #endif
 118   SCROLL_BAR_CLICK_EVENT,       /* .code gives the number of the mouse button
 119                                    that was clicked.
 120                                    .modifiers holds the state of the modifier
 121                                    keys.
 122                                    .part is a lisp symbol indicating which
 123                                    part of the scroll bar got clicked.
 124                                    .x gives the distance from the start of the
 125                                    scroll bar of the click; .y gives the total
 126                                    length of the scroll bar.
 127                                    .frame_or_window gives the window
 128                                    whose scroll bar was clicked in.
 129                                    .timestamp gives a timestamp (in
 130                                    milliseconds) for the click.  */
 131   SELECTION_REQUEST_EVENT,      /* Another X client wants a selection from us.
 132                                    See `struct selection_input_event'.  */
 133   SELECTION_CLEAR_EVENT,        /* Another X client cleared our selection.  */
 134   BUFFER_SWITCH_EVENT,          /* A process filter has switched buffers.  */
 135   DELETE_WINDOW_EVENT,          /* An X client said "delete this window".  */
 136   MENU_BAR_EVENT,               /* An event generated by the menu bar.
 137                                    The frame_or_window field's cdr holds the
 138                                    Lisp-level event value.
 139                                    (Only the toolkit version uses these.)  */
 140   ICONIFY_EVENT,                /* An X client iconified this window.  */
 141   DEICONIFY_EVENT,              /* An X client deiconified this window.  */
 142   MENU_BAR_ACTIVATE_EVENT,      /* A button press in the menu bar
 143                                    (toolkit version only).  */
 144   DRAG_N_DROP_EVENT,            /* A drag-n-drop event is generated when
 145                                    files selected outside of Emacs are dropped
 146                                    onto an Emacs window.
 147                                    .modifiers holds the state of the
 148                                    modifier keys.
 149                                    .x and .y give the mouse position,
 150                                    in characters, within the window.
 151                                    .frame_or_window is the frame in
 152                                    which the drop was made.
 153                                    .arg is a platform-dependent
 154                                    representation of the dropped items.
 155                                    .timestamp gives a timestamp (in
 156                                    milliseconds) for the click.  */
 157   USER_SIGNAL_EVENT,            /* A user signal.
 158                                    code is a number identifying it,
 159                                    index into lispy_user_signals.  */
 160
 161   /* Help events.  Member `frame_or_window' of the input_event is the
 162      frame on which the event occurred, and member `arg' contains
 163      the help to show.  */
 164   HELP_EVENT,
 165
 166   /* An event from a tool-bar.  Member `arg' of the input event
 167      contains the tool-bar item selected.  If `frame_or_window'
 168      and `arg' are equal, this is a prefix event.  */
 169   TOOL_BAR_EVENT,
 170
 171   /* Queued from XTread_socket on FocusIn events.  Translated into
 172      `switch-frame' events in kbd_buffer_get_event, if necessary.  */
 173   FOCUS_IN_EVENT,
 174
 175   /* Generated when mouse moves over window not currently selected.  */
 176   SELECT_WINDOW_EVENT,
 177
 178   /* Queued from XTread_socket when session manager sends
 179      save yourself before shutdown. */
 180   SAVE_SESSION_EVENT
 181
 182 #ifdef HAVE_GPM
 183   , GPM_CLICK_EVENT
 184 #endif
 185
 186 #ifdef HAVE_DBUS
 187   , DBUS_EVENT
 188 #endif
 189
 190   , CONFIG_CHANGED_EVENT
 191
 192 #ifdef HAVE_NTGUI
 193   /* Generated when an APPCOMMAND event is received, in response to
 194      Multimedia or Internet buttons on some keyboards.
 195      Such keys are available as normal function keys on X through the
 196      Xkeyboard extension.
 197      On Windows, some of them get mapped to normal function key events,
 198      but others need to be handled by APPCOMMAND. Handling them all as
 199      APPCOMMAND events means they can be disabled
 200      (w32-pass-multimedia-buttons-to-system), important on Windows since
 201      the system never sees these keys if Emacs claims to handle them.
 202      On X, the window manager seems to grab the keys it wants
 203      first, so this is not a problem there.  */
 204   , MULTIMEDIA_KEY_EVENT
 205 #endif
 206
 207 #ifdef HAVE_NS
 208   /* Generated when native multi-keystroke input method is used to modify
 209      tentative or indicative text display. */
 210   , NS_TEXT_EVENT
 211   /* Non-key system events (e.g. application menu events) */
 212   , NS_NONKEY_EVENT
 213 #endif
 214
 215 #if defined (HAVE_INOTIFY) || defined (HAVE_NTGUI)
 216   /* File or directory was changed.  */
 217   , FILE_NOTIFY_EVENT
 218 #endif
 219
 220 };
 221
 222 /* If a struct input_event has a kind which is SELECTION_REQUEST_EVENT
 223    or SELECTION_CLEAR_EVENT, then its contents are really described
 224    by `struct selection_input_event'; see xterm.h.  */
 225
 226 /* The keyboard input buffer is an array of these structures.  Each one
 227    represents some sort of input event - a keystroke, a mouse click, or
 228    a window system event.  These get turned into their lispy forms when
 229    they are removed from the event queue.  */
 230
 231 struct input_event
 232 {
 233   /* What kind of event was this?  */
 234   enum event_kind kind;
 235
 236   /* For an ASCII_KEYSTROKE_EVENT and MULTIBYTE_CHAR_KEYSTROKE_EVENT,
 237      this is the character.
 238      For a NON_ASCII_KEYSTROKE_EVENT, this is the keysym code.
 239      For a mouse event, this is the button number.
 240      For a HELP_EVENT, this is the position within the object
 241       (stored in ARG below) where the help was found.  */
 242   /* In WindowsNT, for a mouse wheel event, this is the delta.  */
 243   ptrdiff_t code;
 244   enum scroll_bar_part part;
 245
 246   int modifiers;                /* See enum below for interpretation.  */
 247
 248   Lisp_Object x, y;
 249   Time timestamp;
 250
 251   /* This field is copied into a vector while the event is in
 252      the queue, so that garbage collections won't kill it.  */
 253   Lisp_Object frame_or_window;
 254
 255   /* Additional event argument.  This is used for TOOL_BAR_EVENTs and
 256      HELP_EVENTs and avoids calling Fcons during signal handling.  */
 257   Lisp_Object arg;
 258 };
 259
 260 #define EVENT_INIT(event) memset (&(event), 0, sizeof (struct input_event))
 261
 262 /* Bits in the modifiers member of the input_event structure.
 263    Note that reorder_modifiers assumes that the bits are in canonical
 264    order.
 265
 266    The modifiers applied to mouse clicks are rather ornate.  The
 267    window-system-specific code should store mouse clicks with
 268    up_modifier or down_modifier set.  Having an explicit down modifier
 269    simplifies some of window-system-independent code; without it, the
 270    code would have to recognize down events by checking if the event
 271    is a mouse click lacking the click and drag modifiers.
 272
 273    The window-system independent code turns all up_modifier events
 274    bits into drag_modifier, click_modifier, double_modifier, or
 275    triple_modifier events.  The click_modifier has no written
 276    representation in the names of the symbols used as event heads,
 277    but it does appear in the Qevent_symbol_components property of the
 278    event heads.  */
 279 enum {
 280   up_modifier   =   1,          /* Only used on mouse buttons - always
 281                                    turned into a click or a drag modifier
 282                                    before lisp code sees the event.  */
 283   down_modifier =   2,          /* Only used on mouse buttons.  */
 284   drag_modifier =   4,          /* This is never used in the event
 285                                    queue; it's only used internally by
 286                                    the window-system-independent code.  */
 287   click_modifier=   8,          /* See drag_modifier.  */
 288   double_modifier= 16,          /* See drag_modifier.  */
 289   triple_modifier= 32,          /* See drag_modifier.  */
 290
 291   /* The next four modifier bits are used also in keyboard events at
 292      the Lisp level.
 293
 294      It's probably not the greatest idea to use the 2^28 bit for any
 295      modifier.  It may or may not be the sign bit, depending on
 296      FIXNUM_BITS, so using it to represent a modifier key means that
 297      characters thus modified have different integer equivalents
 298      depending on the architecture they're running on.  Oh, and
 299      applying XINT to a character whose 2^28 bit is set might sign-extend
 300      it, so you get a bunch of bits in the mask you didn't want.
 301
 302      The CHAR_ macros are defined in lisp.h.  */
 303   alt_modifier  =  CHAR_ALT,    /* Under X, the XK_Alt_[LR] keysyms.  */
 304   super_modifier=  CHAR_SUPER,  /* Under X, the XK_Super_[LR] keysyms.  */
 305   hyper_modifier=  CHAR_HYPER,  /* Under X, the XK_Hyper_[LR] keysyms.  */
 306   shift_modifier=  CHAR_SHIFT,
 307   ctrl_modifier =  CHAR_CTL,
 308   meta_modifier =  CHAR_META    /* Under X, the XK_Meta_[LR] keysyms.  */
 309 };
 310
 311 #ifdef HAVE_GPM
 312 #include <gpm.h>
 313 extern int handle_one_term_event (struct tty_display_info *, Gpm_Event *, struct input_event *);
 314 #ifndef HAVE_WINDOW_SYSTEM
 315 extern void term_mouse_moveto (int, int);
 316 #endif
 317
 318 /* The device for which we have enabled gpm support.  */
 319 extern struct tty_display_info *gpm_tty;
 320 #endif
 321
 322 \f
 323 struct ns_display_info;
 324 struct x_display_info;
 325 struct w32_display_info;
 326
 327 /* Terminal-local parameters. */
 328 struct terminal
 329 {
 330   /* This is for Lisp; the terminal code does not refer to it.  */
 331   struct vectorlike_header header;
 332
 333   /* Parameter alist of this terminal.  */
 334   Lisp_Object param_alist;
 335
 336   /* List of charsets supported by the terminal.  It is set by
 337      Fset_terminal_coding_system_internal along with
 338      the member terminal_coding.  */
 339   Lisp_Object charset_list;
 340
 341   /* This is an association list containing the X selections that
 342      Emacs might own on this terminal.  Each element has the form
 343        (SELECTION-NAME SELECTION-VALUE SELECTION-TIMESTAMP FRAME)
 344      SELECTION-NAME is a lisp symbol, whose name is the name of an X Atom.
 345      SELECTION-VALUE is the value that emacs owns for that selection.
 346       It may be any kind of Lisp object.
 347      SELECTION-TIMESTAMP is the time at which emacs began owning this
 348       selection, as a cons of two 16-bit numbers (making a 32 bit
 349       time.)
 350      FRAME is the frame for which we made the selection.  If there is
 351       an entry in this alist, then it can be assumed that Emacs owns
 352       that selection.
 353      The only (eq) parts of this list that are visible from Lisp are
 354     the selection-values.  */
 355   Lisp_Object Vselection_alist;
 356
 357   /* All fields before `next_terminal' should be Lisp_Object and are traced
 358      by the GC.  All fields afterwards are ignored by the GC.  */
 359
 360   /* Chain of all terminal devices. */
 361   struct terminal *next_terminal;
 362
 363   /* Unique id for this terminal device. */
 364   int id;
 365
 366   /* The number of frames that are on this terminal. */
 367   int reference_count;
 368
 369   /* The type of the terminal device. */
 370   enum output_method type;
 371
 372   /* The name of the terminal device.  Do not use this to uniquely
 373      identify a terminal; the same device may be opened multiple
 374      times. */
 375   char *name;
 376
 377   /* The terminal's keyboard object. */
 378   struct kboard *kboard;
 379
 380 #ifdef HAVE_WINDOW_SYSTEM
 381   /* Cache of images.  */
 382   struct image_cache *image_cache;
 383 #endif /* HAVE_WINDOW_SYSTEM */
 384
 385   /* Device-type dependent data shared amongst all frames on this terminal.  */
 386   union display_info
 387   {
 388     struct tty_display_info *tty;     /* termchar.h */
 389     struct x_display_info *x;         /* xterm.h */
 390     struct w32_display_info *w32;     /* w32term.h */
 391     struct ns_display_info *ns;       /* nsterm.h */
 392   } display_info;
 393
 394 \f
 395   /* Coding-system to be used for encoding terminal output.  This
 396      structure contains information of a coding-system specified by
 397      the function `set-terminal-coding-system'.  Also see
 398      `safe_terminal_coding' in coding.h.  */
 399   struct coding_system *terminal_coding;
 400
 401   /* Coding-system of what is sent from terminal keyboard.  This
 402      structure contains information of a coding-system specified by
 403      the function `set-keyboard-coding-system'.  */
 404   struct coding_system *keyboard_coding;
 405
 406   /* Terminal characteristics.  */
 407   /* XXX Are these really used on non-termcap displays?  */
 408
 409   int must_write_spaces;        /* Nonzero means spaces in the text must
 410                                    actually be output; can't just skip over
 411                                    some columns to leave them blank.  */
 412   int fast_clear_end_of_line;   /* Nonzero means terminal has a `ce' string.  */
 413
 414   int line_ins_del_ok;          /* Terminal can insert and delete lines.  */
 415   int char_ins_del_ok;          /* Terminal can insert and delete chars.  */
 416   int scroll_region_ok;         /* Terminal supports setting the scroll
 417                                    window.  */
 418   int scroll_region_cost;       /* Cost of setting the scroll window,
 419                                    measured in characters.  */
 420   int memory_below_frame;       /* Terminal remembers lines scrolled
 421                                    off bottom.  */
 422
 423   /* Window-based redisplay interface for this device (0 for tty
 424      devices). */
 425   struct redisplay_interface *rif;
 426
 427   /* Frame-based redisplay interface. */
 428
 429   /* Text display hooks.  */
 430
 431   void (*cursor_to_hook) (struct frame *f, int vpos, int hpos);
 432   void (*raw_cursor_to_hook) (struct frame *, int, int);
 433
 434   void (*clear_to_end_hook) (struct frame *);
 435   void (*clear_frame_hook) (struct frame *);
 436   void (*clear_end_of_line_hook) (struct frame *, int);
 437
 438   void (*ins_del_lines_hook) (struct frame *f, int, int);
 439
 440   void (*insert_glyphs_hook) (struct frame *f, struct glyph *s, int n);
 441   void (*write_glyphs_hook) (struct frame *f, struct glyph *s, int n);
 442   void (*delete_glyphs_hook) (struct frame *, int);
 443
 444   void (*ring_bell_hook) (struct frame *f);
 445   void (*toggle_invisible_pointer_hook) (struct frame *f, int invisible);
 446
 447   void (*reset_terminal_modes_hook) (struct terminal *);
 448   void (*set_terminal_modes_hook) (struct terminal *);
 449
 450   void (*update_begin_hook) (struct frame *);
 451   void (*update_end_hook) (struct frame *);
 452   void (*set_terminal_window_hook) (struct frame *, int);
 453
 454   /* Multi-frame and mouse support hooks.  */
 455
 456   /* Return the current position of the mouse.
 457
 458      Set *f to the frame the mouse is in, or zero if the mouse is in no
 459      Emacs frame.  If it is set to zero, all the other arguments are
 460      garbage.
 461
 462      If the motion started in a scroll bar, set *bar_window to the
 463      scroll bar's window, *part to the part the mouse is currently over,
 464      *x to the position of the mouse along the scroll bar, and *y to the
 465      overall length of the scroll bar.
 466
 467      Otherwise, set *bar_window to Qnil, and *x and *y to the column and
 468      row of the character cell the mouse is over.
 469
 470      Set *time to the time the mouse was at the returned position.  */
 471   void (*mouse_position_hook) (struct frame **f, int,
 472                                Lisp_Object *bar_window,
 473                                enum scroll_bar_part *part,
 474                                Lisp_Object *x,
 475                                Lisp_Object *y,
 476                                Time *);
 477
 478   /* When a frame's focus redirection is changed, this hook tells the
 479      window system code to re-decide where to put the highlight.  Under
 480      X, this means that Emacs lies about where the focus is.  */
 481   void (*frame_rehighlight_hook) (struct frame *);
 482
 483   /* If we're displaying frames using a window system that can stack
 484      frames on top of each other, this hook allows you to bring a frame
 485      to the front, or bury it behind all the other windows.  If this
 486      hook is zero, that means the terminal we're displaying on doesn't
 487      support overlapping frames, so there's no need to raise or lower
 488      anything.
 489
 490      If RAISE_FLAG is non-zero, F is brought to the front, before all other
 491      windows.  If RAISE_FLAG is zero, F is sent to the back, behind all other
 492      windows.  */
 493   void (*frame_raise_lower_hook) (struct frame *f, int raise_flag);
 494
 495   /* If the value of the frame parameter changed, whis hook is called.
 496      For example, if going from fullscreen to not fullscreen this hook
 497      may do something OS dependent, like extended window manager hints on X11.  */
 498   void (*fullscreen_hook) (struct frame *f);
 499
 500   \f
 501   /* Scroll bar hooks.  */
 502
 503   /* The representation of scroll bars is determined by the code which
 504      implements them, except for one thing: they must be represented by
 505      lisp objects.  This allows us to place references to them in
 506      Lisp_Windows without worrying about those references becoming
 507      dangling references when the scroll bar is destroyed.
 508
 509      The window-system-independent portion of Emacs just refers to
 510      scroll bars via their windows, and never looks inside the scroll bar
 511      representation; it always uses hook functions to do all the
 512      scroll bar manipulation it needs.
 513
 514      The `vertical_scroll_bar' field of a Lisp_Window refers to that
 515      window's scroll bar, or is nil if the window doesn't have a
 516      scroll bar.
 517
 518      The `scroll_bars' and `condemned_scroll_bars' fields of a Lisp_Frame
 519      are free for use by the scroll bar implementation in any way it sees
 520      fit.  They are marked by the garbage collector.  */
 521
 522
 523   /* Set the vertical scroll bar for WINDOW to have its upper left corner
 524      at (TOP, LEFT), and be LENGTH rows high.  Set its handle to
 525      indicate that we are displaying PORTION characters out of a total
 526      of WHOLE characters, starting at POSITION.  If WINDOW doesn't yet
 527      have a scroll bar, create one for it.  */
 528   void (*set_vertical_scroll_bar_hook) (struct window *window,
 529                                         int portion, int whole,
 530                                         int position);
 531
 532
 533   /* The following three hooks are used when we're doing a thorough
 534      redisplay of the frame.  We don't explicitly know which scroll bars
 535      are going to be deleted, because keeping track of when windows go
 536      away is a real pain - can you say set-window-configuration?
 537      Instead, we just assert at the beginning of redisplay that *all*
 538      scroll bars are to be removed, and then save scroll bars from the
 539      fiery pit when we actually redisplay their window.  */
 540
 541   /* Arrange for all scroll bars on FRAME to be removed at the next call
 542      to `*judge_scroll_bars_hook'.  A scroll bar may be spared if
 543      `*redeem_scroll_bar_hook' is applied to its window before the judgment.
 544
 545      This should be applied to each frame each time its window tree is
 546      redisplayed, even if it is not displaying scroll bars at the moment;
 547      if the HAS_SCROLL_BARS flag has just been turned off, only calling
 548      this and the judge_scroll_bars_hook will get rid of them.
 549
 550      If non-zero, this hook should be safe to apply to any frame,
 551      whether or not it can support scroll bars, and whether or not it is
 552      currently displaying them.  */
 553   void (*condemn_scroll_bars_hook) (struct frame *frame);
 554
 555   /* Unmark WINDOW's scroll bar for deletion in this judgment cycle.
 556      Note that it's okay to redeem a scroll bar that is not condemned.  */
 557   void (*redeem_scroll_bar_hook) (struct window *window);
 558
 559   /* Remove all scroll bars on FRAME that haven't been saved since the
 560      last call to `*condemn_scroll_bars_hook'.
 561
 562      This should be applied to each frame after each time its window
 563      tree is redisplayed, even if it is not displaying scroll bars at the
 564      moment; if the HAS_SCROLL_BARS flag has just been turned off, only
 565      calling this and condemn_scroll_bars_hook will get rid of them.
 566
 567      If non-zero, this hook should be safe to apply to any frame,
 568      whether or not it can support scroll bars, and whether or not it is
 569      currently displaying them.  */
 570   void (*judge_scroll_bars_hook) (struct frame *FRAME);
 571
 572 \f
 573   /* Called to read input events.
 574
 575      TERMINAL indicates which terminal device to read from.  Input
 576      events should be read into HOLD_QUIT.
 577
 578      A positive return value indicates that that many input events
 579      were read into BUF.
 580      Zero means no events were immediately available.
 581      A value of -1 means a transient read error, while -2 indicates
 582      that the device was closed (hangup), and it should be deleted.  */
 583   int (*read_socket_hook) (struct terminal *terminal,
 584                            struct input_event *hold_quit);
 585
 586   /* Called when a frame's display becomes entirely up to date.  */
 587   void (*frame_up_to_date_hook) (struct frame *);
 588
 589 \f
 590   /* Called to delete the device-specific portions of a frame that is
 591      on this terminal device. */
 592   void (*delete_frame_hook) (struct frame *);
 593
 594   /* Called after the last frame on this terminal is deleted, or when
 595      the display device was closed (hangup).
 596
 597      If this is NULL, then the generic delete_terminal is called
 598      instead.  Otherwise the hook must call delete_terminal itself.
 599
 600      The hook must check for and close any live frames that are still
 601      on the terminal.  delete_frame ensures that there are no live
 602      frames on the terminal when it calls this hook, so infinite
 603      recursion is prevented.  */
 604   void (*delete_terminal_hook) (struct terminal *);
 605 };
 606
 607 /* Most code should use these functions to set Lisp fields in struct
 608    terminal.  */
 609 TERMHOOKS_INLINE void
 610 tset_charset_list (struct terminal *t, Lisp_Object val)
 611 {
 612   t->charset_list = val;
 613 }
 614 TERMHOOKS_INLINE void
 615 tset_selection_alist (struct terminal *t, Lisp_Object val)
 616 {
 617   t->Vselection_alist = val;
 618 }
 619
 620 /* Chain of all terminal devices currently in use.  */
 621 extern struct terminal *terminal_list;
 622
 623 #define FRAME_MUST_WRITE_SPACES(f) ((f)->terminal->must_write_spaces)
 624 #define FRAME_FAST_CLEAR_END_OF_LINE(f) ((f)->terminal->fast_clear_end_of_line)
 625 #define FRAME_LINE_INS_DEL_OK(f) ((f)->terminal->line_ins_del_ok)
 626 #define FRAME_CHAR_INS_DEL_OK(f) ((f)->terminal->char_ins_del_ok)
 627 #define FRAME_SCROLL_REGION_OK(f) ((f)->terminal->scroll_region_ok)
 628 #define FRAME_SCROLL_REGION_COST(f) ((f)->terminal->scroll_region_cost)
 629 #define FRAME_MEMORY_BELOW_FRAME(f) ((f)->terminal->memory_below_frame)
 630
 631 #define FRAME_TERMINAL_CODING(f) ((f)->terminal->terminal_coding)
 632 #define FRAME_KEYBOARD_CODING(f) ((f)->terminal->keyboard_coding)
 633
 634 #define TERMINAL_TERMINAL_CODING(d) ((d)->terminal_coding)
 635 #define TERMINAL_KEYBOARD_CODING(d) ((d)->keyboard_coding)
 636
 637 #define FRAME_RIF(f) ((f)->terminal->rif)
 638
 639 #define FRAME_TERMINAL(f) ((f)->terminal)
 640
 641 /* Return true if the terminal device is not suspended.  */
 642 #define TERMINAL_ACTIVE_P(d)                                            \
 643   (((d)->type != output_termcap && (d)->type != output_msdos_raw)       \
 644    || (d)->display_info.tty->input)
 645
 646 extern struct terminal *get_terminal (Lisp_Object terminal, int);
 647 extern struct terminal *create_terminal (void);
 648 extern void delete_terminal (struct terminal *);
 649
 650 /* The initial terminal device, created by initial_term_init.  */
 651 extern struct terminal *initial_terminal;
 652
 653 extern unsigned char *encode_terminal_code (struct glyph *, int,
 654                                             struct coding_system *);
 655
 656 #ifdef HAVE_GPM
 657 extern void close_gpm (int gpm_fd);
 658 #endif
 659
 660 INLINE_HEADER_END