src/termhooks.h

   1 /* Parameters and display hooks for terminal devices.
   2
   3 Copyright (C) 1985-1986, 1993-1994, 2001-2012  Free Software Foundation, Inc.
   4
   5 This file is part of GNU Emacs.
   6
   7 GNU Emacs is free software: you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation, either version 3 of the License, or
  10 (at your option) any later version.
  11
  12 GNU Emacs is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 \f
  21 /* Miscellanea.   */
  22
  23 #include "systime.h" /* for Time */
  24
  25 INLINE_HEADER_BEGIN
  26 #ifndef TERMHOOKS_INLINE
  27 # define TERMHOOKS_INLINE INLINE
  28 #endif
  29
  30 struct glyph;
  31 struct frame;
  32 \f
  33
  34 enum scroll_bar_part {
  35   scroll_bar_above_handle,
  36   scroll_bar_handle,
  37   scroll_bar_below_handle,
  38   scroll_bar_up_arrow,
  39   scroll_bar_down_arrow,
  40   scroll_bar_to_top,
  41   scroll_bar_to_bottom,
  42   scroll_bar_end_scroll,
  43   scroll_bar_move_ratio
  44 };
  45
  46 /* If the value of the frame parameter changed, whis hook is called.
  47    For example, if going from fullscreen to not fullscreen this hook
  48    may do something OS dependent, like extended window manager hints on X11.  */
  49 extern void (*fullscreen_hook) (struct frame *f);
  50
  51 \f
  52 /* Input queue declarations and hooks.  */
  53
  54 enum event_kind
  55 {
  56   NO_EVENT,                     /* nothing happened.  This should never
  57                                    actually appear in the event queue.  */
  58
  59   ASCII_KEYSTROKE_EVENT,        /* The ASCII code is in .code, perhaps
  60                                    with modifiers applied.
  61                                    .modifiers holds the state of the
  62                                    modifier keys.
  63                                    .frame_or_window is the frame in
  64                                    which the key was typed.
  65                                    .timestamp gives a timestamp (in
  66                                    milliseconds) for the keystroke.  */
  67   MULTIBYTE_CHAR_KEYSTROKE_EVENT,       /* The multibyte char code is in .code,
  68                                    perhaps with modifiers applied.
  69                                    The others are the same as
  70                                    ASCII_KEYSTROKE_EVENT.  */
  71   NON_ASCII_KEYSTROKE_EVENT,    /* .code is a number identifying the
  72                                    function key.  A code N represents
  73                                    a key whose name is
  74                                    function_key_names[N]; function_key_names
  75                                    is a table in keyboard.c to which you
  76                                    should feel free to add missing keys.
  77                                    .modifiers holds the state of the
  78                                    modifier keys.
  79                                    .frame_or_window is the frame in
  80                                    which the key was typed.
  81                                    .timestamp gives a timestamp (in
  82                                    milliseconds) for the keystroke.  */
  83   TIMER_EVENT,                  /* A timer fired.  */
  84   MOUSE_CLICK_EVENT,            /* The button number is in .code; it must
  85                                    be >= 0 and < NUM_MOUSE_BUTTONS, defined
  86                                    below.
  87                                    .modifiers holds the state of the
  88                                    modifier keys.
  89                                    .x and .y give the mouse position,
  90                                    in characters, within the window.
  91                                    .frame_or_window gives the frame
  92                                    the mouse click occurred in.
  93                                    .timestamp gives a timestamp (in
  94                                    milliseconds) for the click.  */
  95   WHEEL_EVENT,                  /* A wheel event is generated by a
  96                                    wheel on a mouse (e.g., MS
  97                                    Intellimouse).
  98                                    .modifiers holds the rotate
  99                                    direction (up or down), and the
 100                                    state of the modifier keys.
 101                                    .x and .y give the mouse position,
 102                                    in characters, within the window.
 103                                    .frame_or_window gives the frame
 104                                    the wheel event occurred in.
 105                                    .timestamp gives a timestamp (in
 106                                    milliseconds) for the event.  */
 107   HORIZ_WHEEL_EVENT,            /* A wheel event generated by a second
 108                                    horizontal wheel that is present on some
 109                                    mice. See WHEEL_EVENT.  */
 110 #ifdef HAVE_NTGUI
 111   LANGUAGE_CHANGE_EVENT,        /* A LANGUAGE_CHANGE_EVENT is
 112                                    generated when HAVE_NTGUI or on Mac OS
 113                                    when the keyboard layout or input
 114                                    language is changed by the
 115                                    user.  */
 116 #endif
 117   SCROLL_BAR_CLICK_EVENT,       /* .code gives the number of the mouse button
 118                                    that was clicked.
 119                                    .modifiers holds the state of the modifier
 120                                    keys.
 121                                    .part is a lisp symbol indicating which
 122                                    part of the scroll bar got clicked.
 123                                    .x gives the distance from the start of the
 124                                    scroll bar of the click; .y gives the total
 125                                    length of the scroll bar.
 126                                    .frame_or_window gives the window
 127                                    whose scroll bar was clicked in.
 128                                    .timestamp gives a timestamp (in
 129                                    milliseconds) for the click.  */
 130   SELECTION_REQUEST_EVENT,      /* Another X client wants a selection from us.
 131                                    See `struct selection_input_event'.  */
 132   SELECTION_CLEAR_EVENT,        /* Another X client cleared our selection.  */
 133   BUFFER_SWITCH_EVENT,          /* A process filter has switched buffers.  */
 134   DELETE_WINDOW_EVENT,          /* An X client said "delete this window".  */
 135   MENU_BAR_EVENT,               /* An event generated by the menu bar.
 136                                    The frame_or_window field's cdr holds the
 137                                    Lisp-level event value.
 138                                    (Only the toolkit version uses these.)  */
 139   ICONIFY_EVENT,                /* An X client iconified this window.  */
 140   DEICONIFY_EVENT,              /* An X client deiconified this window.  */
 141   MENU_BAR_ACTIVATE_EVENT,      /* A button press in the menu bar
 142                                    (toolkit version only).  */
 143   DRAG_N_DROP_EVENT,            /* A drag-n-drop event is generated when
 144                                    files selected outside of Emacs are dropped
 145                                    onto an Emacs window.
 146                                    .modifiers holds the state of the
 147                                    modifier keys.
 148                                    .x and .y give the mouse position,
 149                                    in characters, within the window.
 150                                    .frame_or_window is the frame in
 151                                    which the drop was made.
 152                                    .arg is a platform-dependent
 153                                    representation of the dropped items.
 154                                    .timestamp gives a timestamp (in
 155                                    milliseconds) for the click.  */
 156   USER_SIGNAL_EVENT,            /* A user signal.
 157                                    code is a number identifying it,
 158                                    index into lispy_user_signals.  */
 159
 160   /* Help events.  Member `frame_or_window' of the input_event is the
 161      frame on which the event occurred, and member `arg' contains
 162      the help to show.  */
 163   HELP_EVENT,
 164
 165   /* An event from a tool-bar.  Member `arg' of the input event
 166      contains the tool-bar item selected.  If `frame_or_window'
 167      and `arg' are equal, this is a prefix event.  */
 168   TOOL_BAR_EVENT,
 169
 170   /* Queued from XTread_socket on FocusIn events.  Translated into
 171      `switch-frame' events in kbd_buffer_get_event, if necessary.  */
 172   FOCUS_IN_EVENT,
 173
 174   /* Generated when mouse moves over window not currently selected.  */
 175   SELECT_WINDOW_EVENT,
 176
 177   /* Queued from XTread_socket when session manager sends
 178      save yourself before shutdown. */
 179   SAVE_SESSION_EVENT
 180
 181 #ifdef HAVE_GPM
 182   , GPM_CLICK_EVENT
 183 #endif
 184
 185 #ifdef HAVE_DBUS
 186   , DBUS_EVENT
 187 #endif
 188
 189   , CONFIG_CHANGED_EVENT
 190
 191 #ifdef HAVE_NTGUI
 192   /* Generated when an APPCOMMAND event is received, in response to
 193      Multimedia or Internet buttons on some keyboards.
 194      Such keys are available as normal function keys on X through the
 195      Xkeyboard extension.
 196      On Windows, some of them get mapped to normal function key events,
 197      but others need to be handled by APPCOMMAND. Handling them all as
 198      APPCOMMAND events means they can be disabled
 199      (w32-pass-multimedia-buttons-to-system), important on Windows since
 200      the system never sees these keys if Emacs claims to handle them.
 201      On X, the window manager seems to grab the keys it wants
 202      first, so this is not a problem there.  */
 203   , MULTIMEDIA_KEY_EVENT
 204 #endif
 205
 206 #ifdef HAVE_NS
 207   /* Generated when native multi-keystroke input method is used to modify
 208      tentative or indicative text display. */
 209   , NS_TEXT_EVENT
 210   /* Non-key system events (e.g. application menu events) */
 211   , NS_NONKEY_EVENT
 212 #endif
 213
 214 #if defined (HAVE_INOTIFY) || defined (HAVE_NTGUI)
 215   /* File or directory was changed.  */
 216   , FILE_NOTIFY_EVENT
 217 #endif
 218
 219 };
 220
 221 /* If a struct input_event has a kind which is SELECTION_REQUEST_EVENT
 222    or SELECTION_CLEAR_EVENT, then its contents are really described
 223    by `struct selection_input_event'; see xterm.h.  */
 224
 225 /* The keyboard input buffer is an array of these structures.  Each one
 226    represents some sort of input event - a keystroke, a mouse click, or
 227    a window system event.  These get turned into their lispy forms when
 228    they are removed from the event queue.  */
 229
 230 struct input_event
 231 {
 232   /* What kind of event was this?  */
 233   enum event_kind kind;
 234
 235   /* For an ASCII_KEYSTROKE_EVENT and MULTIBYTE_CHAR_KEYSTROKE_EVENT,
 236      this is the character.
 237      For a NON_ASCII_KEYSTROKE_EVENT, this is the keysym code.
 238      For a mouse event, this is the button number.
 239      For a HELP_EVENT, this is the position within the object
 240       (stored in ARG below) where the help was found.  */
 241   /* In WindowsNT, for a mouse wheel event, this is the delta.  */
 242   ptrdiff_t code;
 243   enum scroll_bar_part part;
 244
 245   int modifiers;                /* See enum below for interpretation.  */
 246
 247   Lisp_Object x, y;
 248   Time timestamp;
 249
 250   /* This field is copied into a vector while the event is in
 251      the queue, so that garbage collections won't kill 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) memset (&(event), 0, 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 2^28 bit for any
 294      modifier.  It may or may not be the sign bit, depending on
 295      FIXNUM_BITS, 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 2^28 bit is set might sign-extend
 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 #ifndef HAVE_WINDOW_SYSTEM
 314 extern void term_mouse_moveto (int, int);
 315 #endif
 316
 317 /* The device for which we have enabled gpm support.  */
 318 extern struct tty_display_info *gpm_tty;
 319 #endif
 320
 321 \f
 322 struct ns_display_info;
 323 struct x_display_info;
 324 struct w32_display_info;
 325
 326 /* Terminal-local parameters. */
 327 struct terminal
 328 {
 329   /* This is for Lisp; the terminal code does not refer to it.  */
 330   struct vectorlike_header header;
 331
 332   /* Parameter alist of this terminal.  */
 333   Lisp_Object param_alist;
 334
 335   /* List of charsets supported by the terminal.  It is set by
 336      Fset_terminal_coding_system_internal along with
 337      the member terminal_coding.  */
 338   Lisp_Object charset_list;
 339
 340   /* This is an association list containing the X selections that
 341      Emacs might own on this terminal.  Each element has the form
 342        (SELECTION-NAME SELECTION-VALUE SELECTION-TIMESTAMP FRAME)
 343      SELECTION-NAME is a lisp symbol, whose name is the name of an X Atom.
 344      SELECTION-VALUE is the value that emacs owns for that selection.
 345       It may be any kind of Lisp object.
 346      SELECTION-TIMESTAMP is the time at which emacs began owning this
 347       selection, as a cons of two 16-bit numbers (making a 32 bit
 348       time.)
 349      FRAME is the frame for which we made the selection.  If there is
 350       an entry in this alist, then it can be assumed that Emacs owns
 351       that selection.
 352      The only (eq) parts of this list that are visible from Lisp are
 353     the selection-values.  */
 354   Lisp_Object Vselection_alist;
 355
 356   /* All fields before `next_terminal' should be Lisp_Object and are traced
 357      by the GC.  All fields afterwards are ignored by the GC.  */
 358
 359   /* Chain of all terminal devices. */
 360   struct terminal *next_terminal;
 361
 362   /* Unique id for this terminal device. */
 363   int id;
 364
 365   /* The number of frames that are on this terminal. */
 366   int reference_count;
 367
 368   /* The type of the terminal device. */
 369   enum output_method type;
 370
 371   /* The name of the terminal device.  Do not use this to uniquely
 372      identify a terminal; the same device may be opened multiple
 373      times. */
 374   char *name;
 375
 376   /* The terminal's keyboard object. */
 377   struct kboard *kboard;
 378
 379 #ifdef HAVE_WINDOW_SYSTEM
 380   /* Cache of images.  */
 381   struct image_cache *image_cache;
 382 #endif /* HAVE_WINDOW_SYSTEM */
 383
 384   /* Device-type dependent data shared amongst all frames on this terminal. */
 385   union display_info
 386   {
 387     struct tty_display_info *tty;     /* termchar.h */
 388     struct x_display_info *x;         /* xterm.h */
 389     struct w32_display_info *w32;     /* w32term.h */
 390     struct ns_display_info *ns;       /* nsterm.h */
 391   } display_info;
 392
 393 \f
 394   /* Coding-system to be used for encoding terminal output.  This
 395      structure contains information of a coding-system specified by
 396      the function `set-terminal-coding-system'.  Also see
 397      `safe_terminal_coding' in coding.h.  */
 398   struct coding_system *terminal_coding;
 399
 400   /* Coding-system of what is sent from terminal keyboard.  This
 401      structure contains information of a coding-system specified by
 402      the function `set-keyboard-coding-system'.  */
 403   struct coding_system *keyboard_coding;
 404
 405   /* Terminal characteristics. */
 406   /* XXX Are these really used on non-termcap displays? */
 407
 408   int must_write_spaces;        /* Nonzero means spaces in the text must
 409                                    actually be output; can't just skip over
 410                                    some columns to leave them blank.  */
 411   int fast_clear_end_of_line;   /* Nonzero means terminal has a `ce' string */
 412
 413   int line_ins_del_ok;          /* Terminal can insert and delete lines */
 414   int char_ins_del_ok;          /* Terminal can insert and delete chars */
 415   int scroll_region_ok;         /* Terminal supports setting the scroll
 416                                    window */
 417   int scroll_region_cost;       /* Cost of setting the scroll window,
 418                                    measured in characters. */
 419   int memory_below_frame;       /* Terminal remembers lines scrolled
 420                                    off bottom */
 421
 422   /* Window-based redisplay interface for this device (0 for tty
 423      devices). */
 424   struct redisplay_interface *rif;
 425
 426   /* Frame-based redisplay interface. */
 427
 428   /* Text display hooks.  */
 429
 430   void (*cursor_to_hook) (struct frame *f, int vpos, int hpos);
 431   void (*raw_cursor_to_hook) (struct frame *, int, int);
 432
 433   void (*clear_to_end_hook) (struct frame *);
 434   void (*clear_frame_hook) (struct frame *);
 435   void (*clear_end_of_line_hook) (struct frame *, int);
 436
 437   void (*ins_del_lines_hook) (struct frame *f, int, int);
 438
 439   void (*insert_glyphs_hook) (struct frame *f, struct glyph *s, int n);
 440   void (*write_glyphs_hook) (struct frame *f, struct glyph *s, int n);
 441   void (*delete_glyphs_hook) (struct frame *, int);
 442
 443   void (*ring_bell_hook) (struct frame *f);
 444   void (*toggle_invisible_pointer_hook) (struct frame *f, int invisible);
 445
 446   void (*reset_terminal_modes_hook) (struct terminal *);
 447   void (*set_terminal_modes_hook) (struct terminal *);
 448
 449   void (*update_begin_hook) (struct frame *);
 450   void (*update_end_hook) (struct frame *);
 451   void (*set_terminal_window_hook) (struct frame *, int);
 452
 453   /* Multi-frame and mouse support hooks.  */
 454
 455   /* Return the current position of the mouse.
 456
 457      Set *f to the frame the mouse is in, or zero if the mouse is in no
 458      Emacs frame.  If it is set to zero, all the other arguments are
 459      garbage.
 460
 461      If the motion started in a scroll bar, set *bar_window to the
 462      scroll bar's window, *part to the part the mouse is currently over,
 463      *x to the position of the mouse along the scroll bar, and *y to the
 464      overall length of the scroll bar.
 465
 466      Otherwise, set *bar_window to Qnil, and *x and *y to the column and
 467      row of the character cell the mouse is over.
 468
 469      Set *time to the time the mouse was at the returned position.  */
 470   void (*mouse_position_hook) (struct frame **f, int,
 471                                Lisp_Object *bar_window,
 472                                enum scroll_bar_part *part,
 473                                Lisp_Object *x,
 474                                Lisp_Object *y,
 475                                Time *);
 476
 477   /* When a frame's focus redirection is changed, this hook tells the
 478      window system code to re-decide where to put the highlight.  Under
 479      X, this means that Emacs lies about where the focus is.  */
 480   void (*frame_rehighlight_hook) (struct frame *);
 481
 482   /* If we're displaying frames using a window system that can stack
 483      frames on top of each other, this hook allows you to bring a frame
 484      to the front, or bury it behind all the other windows.  If this
 485      hook is zero, that means the terminal we're displaying on doesn't
 486      support overlapping frames, so there's no need to raise or lower
 487      anything.
 488
 489      If RAISE_FLAG is non-zero, F is brought to the front, before all other
 490      windows.  If RAISE_FLAG is zero, F is sent to the back, behind all other
 491      windows.  */
 492   void (*frame_raise_lower_hook) (struct frame *f, int raise_flag);
 493
 494   /* If the value of the frame parameter changed, whis hook is called.
 495      For example, if going from fullscreen to not fullscreen this hook
 496      may do something OS dependent, like extended window manager hints on X11.  */
 497   void (*fullscreen_hook) (struct frame *f);
 498
 499   \f
 500   /* Scroll bar hooks.  */
 501
 502   /* The representation of scroll bars is determined by the code which
 503      implements them, except for one thing: they must be represented by
 504      lisp objects.  This allows us to place references to them in
 505      Lisp_Windows without worrying about those references becoming
 506      dangling references when the scroll bar is destroyed.
 507
 508      The window-system-independent portion of Emacs just refers to
 509      scroll bars via their windows, and never looks inside the scroll bar
 510      representation; it always uses hook functions to do all the
 511      scroll bar manipulation it needs.
 512
 513      The `vertical_scroll_bar' field of a Lisp_Window refers to that
 514      window's scroll bar, or is nil if the window doesn't have a
 515      scroll bar.
 516
 517      The `scroll_bars' and `condemned_scroll_bars' fields of a Lisp_Frame
 518      are free for use by the scroll bar implementation in any way it sees
 519      fit.  They are marked by the garbage collector.  */
 520
 521
 522   /* Set the vertical scroll bar for WINDOW to have its upper left corner
 523      at (TOP, LEFT), and be LENGTH rows high.  Set its handle to
 524      indicate that we are displaying PORTION characters out of a total
 525      of WHOLE characters, starting at POSITION.  If WINDOW doesn't yet
 526      have a scroll bar, create one for it.  */
 527   void (*set_vertical_scroll_bar_hook) (struct window *window,
 528                                         int portion, int whole,
 529                                         int position);
 530
 531
 532   /* The following three hooks are used when we're doing a thorough
 533      redisplay of the frame.  We don't explicitly know which scroll bars
 534      are going to be deleted, because keeping track of when windows go
 535      away is a real pain - can you say set-window-configuration?
 536      Instead, we just assert at the beginning of redisplay that *all*
 537      scroll bars are to be removed, and then save scroll bars from the
 538      fiery pit when we actually redisplay their window.  */
 539
 540   /* Arrange for all scroll bars on FRAME to be removed at the next call
 541      to `*judge_scroll_bars_hook'.  A scroll bar may be spared if
 542      `*redeem_scroll_bar_hook' is applied to its window before the judgment.
 543
 544      This should be applied to each frame each time its window tree is
 545      redisplayed, even if it is not displaying scroll bars at the moment;
 546      if the HAS_SCROLL_BARS flag has just been turned off, only calling
 547      this and the judge_scroll_bars_hook will get rid of them.
 548
 549      If non-zero, this hook should be safe to apply to any frame,
 550      whether or not it can support scroll bars, and whether or not it is
 551      currently displaying them.  */
 552   void (*condemn_scroll_bars_hook) (struct frame *frame);
 553
 554   /* Unmark WINDOW's scroll bar for deletion in this judgment cycle.
 555      Note that it's okay to redeem a scroll bar that is not condemned.  */
 556   void (*redeem_scroll_bar_hook) (struct window *window);
 557
 558   /* Remove all scroll bars on FRAME that haven't been saved since the
 559      last call to `*condemn_scroll_bars_hook'.
 560
 561      This should be applied to each frame after each time its window
 562      tree is redisplayed, even if it is not displaying scroll bars at the
 563      moment; if the HAS_SCROLL_BARS flag has just been turned off, only
 564      calling this and condemn_scroll_bars_hook will get rid of them.
 565
 566      If non-zero, this hook should be safe to apply to any frame,
 567      whether or not it can support scroll bars, and whether or not it is
 568      currently displaying them.  */
 569   void (*judge_scroll_bars_hook) (struct frame *FRAME);
 570
 571 \f
 572   /* Called to read input events.
 573
 574      TERMINAL indicates which terminal device to read from.  Input
 575      events should be read into HOLD_QUIT.
 576
 577      A positive return value indicates that that many input events
 578      were read into BUF.
 579      Zero means no events were immediately available.
 580      A value of -1 means a transient read error, while -2 indicates
 581      that the device was closed (hangup), and it should be deleted.  */
 582   int (*read_socket_hook) (struct terminal *terminal,
 583                            struct input_event *hold_quit);
 584
 585   /* Called when a frame's display becomes entirely up to date.  */
 586   void (*frame_up_to_date_hook) (struct frame *);
 587
 588 \f
 589   /* Called to delete the device-specific portions of a frame that is
 590      on this terminal device. */
 591   void (*delete_frame_hook) (struct frame *);
 592
 593   /* Called after the last frame on this terminal is deleted, or when
 594      the display device was closed (hangup).
 595
 596      If this is NULL, then the generic delete_terminal is called
 597      instead.  Otherwise the hook must call delete_terminal itself.
 598
 599      The hook must check for and close any live frames that are still
 600      on the terminal.  delete_frame ensures that there are no live
 601      frames on the terminal when it calls this hook, so infinite
 602      recursion is prevented.  */
 603   void (*delete_terminal_hook) (struct terminal *);
 604 };
 605
 606 /* Most code should use these functions to set Lisp fields in struct
 607    terminal.  */
 608 TERMHOOKS_INLINE void
 609 tset_charset_list (struct terminal *t, Lisp_Object val)
 610 {
 611   t->charset_list = val;
 612 }
 613 TERMHOOKS_INLINE void
 614 tset_selection_alist (struct terminal *t, Lisp_Object val)
 615 {
 616   t->Vselection_alist = val;
 617 }
 618
 619 /* Chain of all terminal devices currently in use. */
 620 extern struct terminal *terminal_list;
 621
 622 #define FRAME_MUST_WRITE_SPACES(f) ((f)->terminal->must_write_spaces)
 623 #define FRAME_FAST_CLEAR_END_OF_LINE(f) ((f)->terminal->fast_clear_end_of_line)
 624 #define FRAME_LINE_INS_DEL_OK(f) ((f)->terminal->line_ins_del_ok)
 625 #define FRAME_CHAR_INS_DEL_OK(f) ((f)->terminal->char_ins_del_ok)
 626 #define FRAME_SCROLL_REGION_OK(f) ((f)->terminal->scroll_region_ok)
 627 #define FRAME_SCROLL_REGION_COST(f) ((f)->terminal->scroll_region_cost)
 628 #define FRAME_MEMORY_BELOW_FRAME(f) ((f)->terminal->memory_below_frame)
 629
 630 #define FRAME_TERMINAL_CODING(f) ((f)->terminal->terminal_coding)
 631 #define FRAME_KEYBOARD_CODING(f) ((f)->terminal->keyboard_coding)
 632
 633 #define TERMINAL_TERMINAL_CODING(d) ((d)->terminal_coding)
 634 #define TERMINAL_KEYBOARD_CODING(d) ((d)->keyboard_coding)
 635
 636 #define FRAME_RIF(f) ((f)->terminal->rif)
 637
 638 #define FRAME_TERMINAL(f) ((f)->terminal)
 639
 640 /* Return true if the terminal device is not suspended. */
 641 #define TERMINAL_ACTIVE_P(d) (((d)->type != output_termcap && (d)->type !=output_msdos_raw) || (d)->display_info.tty->input)
 642
 643 extern struct terminal *get_terminal (Lisp_Object terminal, int);
 644 extern struct terminal *create_terminal (void);
 645 extern void delete_terminal (struct terminal *);
 646
 647 /* The initial terminal device, created by initial_term_init. */
 648 extern struct terminal *initial_terminal;
 649
 650 extern unsigned char *encode_terminal_code (struct glyph *, int,
 651                                             struct coding_system *);
 652
 653 #ifdef HAVE_GPM
 654 extern void close_gpm (int gpm_fd);
 655 #endif
 656
 657 INLINE_HEADER_END