src/termhooks.h

   1 /* Parameters and display hooks for terminal devices.
   2
   3 Copyright (C) 1985-1986, 1993-1994, 2001-2015 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 #ifndef EMACS_TERMHOOKS_H
  22 #define EMACS_TERMHOOKS_H
  23
  24 /* Miscellanea.   */
  25
  26 #include "systime.h" /* for Time */
  27
  28 INLINE_HEADER_BEGIN
  29
  30 enum scroll_bar_part {
  31   scroll_bar_nowhere,
  32   scroll_bar_above_handle,
  33   scroll_bar_handle,
  34   scroll_bar_below_handle,
  35   scroll_bar_up_arrow,
  36   scroll_bar_down_arrow,
  37   scroll_bar_to_top,
  38   scroll_bar_to_bottom,
  39   scroll_bar_end_scroll,
  40   scroll_bar_move_ratio,
  41   scroll_bar_before_handle,
  42   scroll_bar_horizontal_handle,
  43   scroll_bar_after_handle,
  44   scroll_bar_left_arrow,
  45   scroll_bar_right_arrow,
  46   scroll_bar_to_leftmost,
  47   scroll_bar_to_rightmost
  48 };
  49
  50 /* Output method of a terminal (and frames on this terminal, respectively).  */
  51
  52 enum output_method
  53 {
  54   output_initial,
  55   output_termcap,
  56   output_x_window,
  57   output_msdos_raw,
  58   output_w32,
  59   output_ns
  60 };
  61
  62 /* Input queue declarations and hooks.  */
  63
  64 enum event_kind
  65 {
  66   NO_EVENT,                     /* nothing happened.  This should never
  67                                    actually appear in the event queue.  */
  68
  69   ASCII_KEYSTROKE_EVENT,        /* The ASCII code is in .code, perhaps
  70                                    with modifiers applied.
  71                                    .modifiers holds the state of the
  72                                    modifier keys.
  73                                    .frame_or_window is the frame in
  74                                    which the key was typed.
  75                                    .timestamp gives a timestamp (in
  76                                    milliseconds) for the keystroke.  */
  77   MULTIBYTE_CHAR_KEYSTROKE_EVENT,       /* The multibyte char code is in .code,
  78                                    perhaps with modifiers applied.
  79                                    The others are the same as
  80                                    ASCII_KEYSTROKE_EVENT.  */
  81   NON_ASCII_KEYSTROKE_EVENT,    /* .code is a number identifying the
  82                                    function key.  A code N represents
  83                                    a key whose name is
  84                                    function_key_names[N]; function_key_names
  85                                    is a table in keyboard.c to which you
  86                                    should feel free to add missing keys.
  87                                    .modifiers holds the state of the
  88                                    modifier keys.
  89                                    .frame_or_window is the frame in
  90                                    which the key was typed.
  91                                    .timestamp gives a timestamp (in
  92                                    milliseconds) for the keystroke.  */
  93   TIMER_EVENT,                  /* A timer fired.  */
  94   MOUSE_CLICK_EVENT,            /* The button number is in .code; it must
  95                                    be >= 0 and < NUM_MOUSE_BUTTONS, defined
  96                                    below.
  97                                    .modifiers holds the state of the
  98                                    modifier keys.
  99                                    .x and .y give the mouse position,
 100                                    in characters, within the window.
 101                                    .frame_or_window gives the frame
 102                                    the mouse click occurred in.
 103                                    .timestamp gives a timestamp (in
 104                                    milliseconds) for the click.  */
 105   WHEEL_EVENT,                  /* A wheel event is generated by a
 106                                    wheel on a mouse (e.g., MS
 107                                    Intellimouse).
 108                                    .modifiers holds the rotate
 109                                    direction (up or down), and the
 110                                    state of the modifier keys.
 111                                    .x and .y give the mouse position,
 112                                    in characters, within the window.
 113                                    .frame_or_window gives the frame
 114                                    the wheel event occurred in.
 115                                    .timestamp gives a timestamp (in
 116                                    milliseconds) for the event.  */
 117   HORIZ_WHEEL_EVENT,            /* A wheel event generated by a second
 118                                    horizontal wheel that is present on some
 119                                    mice. See WHEEL_EVENT.  */
 120 #ifdef HAVE_NTGUI
 121   LANGUAGE_CHANGE_EVENT,        /* A LANGUAGE_CHANGE_EVENT is
 122                                    generated when HAVE_NTGUI or on Mac OS
 123                                    when the keyboard layout or input
 124                                    language is changed by the
 125                                    user.  */
 126 #endif
 127   SCROLL_BAR_CLICK_EVENT,       /* .code gives the number of the mouse button
 128                                    that was clicked.
 129                                    .modifiers holds the state of the modifier
 130                                    keys.
 131                                    .part is a lisp symbol indicating which
 132                                    part of the scroll bar got clicked.
 133                                    .x gives the distance from the start of the
 134                                    scroll bar of the click; .y gives the total
 135                                    length of the scroll bar.
 136                                    .frame_or_window gives the window
 137                                    whose scroll bar was clicked in.
 138                                    .timestamp gives a timestamp (in
 139                                    milliseconds) for the click.  */
 140   HORIZONTAL_SCROLL_BAR_CLICK_EVENT,    /* .code gives the number of the mouse button
 141                                    that was clicked.
 142                                    .modifiers holds the state of the modifier
 143                                    keys.
 144                                    .part is a lisp symbol indicating which
 145                                    part of the scroll bar got clicked.
 146                                    .x gives the distance from the start of the
 147                                    scroll bar of the click; .y gives the total
 148                                    length of the scroll bar.
 149                                    .frame_or_window gives the window
 150                                    whose scroll bar was clicked in.
 151                                    .timestamp gives a timestamp (in
 152                                    milliseconds) for the click.  */
 153   SELECTION_REQUEST_EVENT,      /* Another X client wants a selection from us.
 154                                    See `struct selection_input_event'.  */
 155   SELECTION_CLEAR_EVENT,        /* Another X client cleared our selection.  */
 156   BUFFER_SWITCH_EVENT,          /* A process filter has switched buffers.  */
 157   DELETE_WINDOW_EVENT,          /* An X client said "delete this window".  */
 158   MENU_BAR_EVENT,               /* An event generated by the menu bar.
 159                                    The frame_or_window field's cdr holds the
 160                                    Lisp-level event value.
 161                                    (Only the toolkit version uses these.)  */
 162   ICONIFY_EVENT,                /* An X client iconified this window.  */
 163   DEICONIFY_EVENT,              /* An X client deiconified this window.  */
 164   MENU_BAR_ACTIVATE_EVENT,      /* A button press in the menu bar
 165                                    (toolkit version only).  */
 166   DRAG_N_DROP_EVENT,            /* A drag-n-drop event is generated when
 167                                    files selected outside of Emacs are dropped
 168                                    onto an Emacs window.
 169                                    .modifiers holds the state of the
 170                                    modifier keys.
 171                                    .x and .y give the mouse position,
 172                                    in characters, within the window.
 173                                    .frame_or_window is the frame in
 174                                    which the drop was made.
 175                                    .arg is a platform-dependent
 176                                    representation of the dropped items.
 177                                    .timestamp gives a timestamp (in
 178                                    milliseconds) for the click.  */
 179   USER_SIGNAL_EVENT,            /* A user signal.
 180                                    code is a number identifying it,
 181                                    index into lispy_user_signals.  */
 182
 183   /* Help events.  Member `frame_or_window' of the input_event is the
 184      frame on which the event occurred, and member `arg' contains
 185      the help to show.  */
 186   HELP_EVENT,
 187
 188   /* An event from a tool-bar.  Member `arg' of the input event
 189      contains the tool-bar item selected.  If `frame_or_window'
 190      and `arg' are equal, this is a prefix event.  */
 191   TOOL_BAR_EVENT,
 192
 193   /* Queued from XTread_socket on FocusIn events.  Translated into
 194      `switch-frame' events in kbd_buffer_get_event, if necessary.  */
 195   FOCUS_IN_EVENT,
 196
 197   FOCUS_OUT_EVENT,
 198
 199   /* Generated when mouse moves over window not currently selected.  */
 200   SELECT_WINDOW_EVENT,
 201
 202   /* Queued from XTread_socket when session manager sends
 203      save yourself before shutdown. */
 204   SAVE_SESSION_EVENT
 205
 206 #ifdef HAVE_GPM
 207   , GPM_CLICK_EVENT
 208 #endif
 209
 210 #ifdef HAVE_DBUS
 211   , DBUS_EVENT
 212 #endif
 213
 214   , CONFIG_CHANGED_EVENT
 215
 216 #ifdef HAVE_NTGUI
 217   /* Generated when an APPCOMMAND event is received, in response to
 218      Multimedia or Internet buttons on some keyboards.
 219      Such keys are available as normal function keys on X through the
 220      Xkeyboard extension.
 221      On Windows, some of them get mapped to normal function key events,
 222      but others need to be handled by APPCOMMAND. Handling them all as
 223      APPCOMMAND events means they can be disabled
 224      (w32-pass-multimedia-buttons-to-system), important on Windows since
 225      the system never sees these keys if Emacs claims to handle them.
 226      On X, the window manager seems to grab the keys it wants
 227      first, so this is not a problem there.  */
 228   , MULTIMEDIA_KEY_EVENT
 229 #endif
 230
 231 #ifdef HAVE_NS
 232   /* Generated when native multi-keystroke input method is used to modify
 233      tentative or indicative text display. */
 234   , NS_TEXT_EVENT
 235   /* Non-key system events (e.g. application menu events) */
 236   , NS_NONKEY_EVENT
 237 #endif
 238
 239 #ifdef USE_FILE_NOTIFY
 240   /* File or directory was changed.  */
 241   , FILE_NOTIFY_EVENT
 242 #endif
 243
 244 };
 245
 246 /* Bit width of an enum event_kind tag at the start of structs and unions.  */
 247 enum { EVENT_KIND_WIDTH = 16 };
 248
 249 /* If a struct input_event has a kind which is SELECTION_REQUEST_EVENT
 250    or SELECTION_CLEAR_EVENT, then its contents are really described
 251    by `struct selection_input_event'; see xterm.h.  */
 252
 253 /* The keyboard input buffer is an array of these structures.  Each one
 254    represents some sort of input event - a keystroke, a mouse click, or
 255    a window system event.  These get turned into their lispy forms when
 256    they are removed from the event queue.  */
 257
 258 struct input_event
 259 {
 260   /* What kind of event was this?  */
 261   ENUM_BF (event_kind) kind : EVENT_KIND_WIDTH;
 262
 263   /* Used in scroll back click events.  */
 264   ENUM_BF (scroll_bar_part) part : 16;
 265
 266   /* For an ASCII_KEYSTROKE_EVENT and MULTIBYTE_CHAR_KEYSTROKE_EVENT,
 267      this is the character.
 268      For a NON_ASCII_KEYSTROKE_EVENT, this is the keysym code.
 269      For a mouse event, this is the button number.  */
 270   unsigned code;
 271
 272   /* See enum below for interpretation.  */
 273   unsigned modifiers;
 274
 275   /* One would prefer C integers, but HELP_EVENT uses these to
 276      record frame or window object and a help form, respectively.  */
 277   Lisp_Object x, y;
 278
 279   /* Usually a time as reported by window system-specific event loop.
 280      For a HELP_EVENT, this is the position within the object (stored
 281      in ARG below) where the help was found.  */
 282   Time timestamp;
 283
 284   /* This field is copied into a vector while the event is in
 285      the queue, so that garbage collections won't kill it.  */
 286   Lisp_Object frame_or_window;
 287
 288   /* This additional argument is used in attempt to avoid extra consing
 289      when building events.  Unfortunately some events have to pass much
 290      more data than it's reasonable to pack directly into this structure.  */
 291   Lisp_Object arg;
 292 };
 293
 294 #define EVENT_INIT(event) memset (&(event), 0, sizeof (struct input_event))
 295
 296 /* Bits in the modifiers member of the input_event structure.
 297    Note that reorder_modifiers assumes that the bits are in canonical
 298    order.
 299
 300    The modifiers applied to mouse clicks are rather ornate.  The
 301    window-system-specific code should store mouse clicks with
 302    up_modifier or down_modifier set.  Having an explicit down modifier
 303    simplifies some of window-system-independent code; without it, the
 304    code would have to recognize down events by checking if the event
 305    is a mouse click lacking the click and drag modifiers.
 306
 307    The window-system independent code turns all up_modifier events
 308    bits into drag_modifier, click_modifier, double_modifier, or
 309    triple_modifier events.  The click_modifier has no written
 310    representation in the names of the symbols used as event heads,
 311    but it does appear in the Qevent_symbol_components property of the
 312    event heads.  */
 313 enum {
 314   up_modifier   =   1,          /* Only used on mouse buttons - always
 315                                    turned into a click or a drag modifier
 316                                    before lisp code sees the event.  */
 317   down_modifier =   2,          /* Only used on mouse buttons.  */
 318   drag_modifier =   4,          /* This is never used in the event
 319                                    queue; it's only used internally by
 320                                    the window-system-independent code.  */
 321   click_modifier=   8,          /* See drag_modifier.  */
 322   double_modifier= 16,          /* See drag_modifier.  */
 323   triple_modifier= 32,          /* See drag_modifier.  */
 324
 325   /* The next four modifier bits are used also in keyboard events at
 326      the Lisp level.
 327
 328      It's probably not the greatest idea to use the 2^28 bit for any
 329      modifier.  It may or may not be the sign bit, depending on
 330      FIXNUM_BITS, so using it to represent a modifier key means that
 331      characters thus modified have different integer equivalents
 332      depending on the architecture they're running on.  Oh, and
 333      applying XINT to a character whose 2^28 bit is set might sign-extend
 334      it, so you get a bunch of bits in the mask you didn't want.
 335
 336      The CHAR_ macros are defined in lisp.h.  */
 337   alt_modifier  =  CHAR_ALT,    /* Under X, the XK_Alt_[LR] keysyms.  */
 338   super_modifier=  CHAR_SUPER,  /* Under X, the XK_Super_[LR] keysyms.  */
 339   hyper_modifier=  CHAR_HYPER,  /* Under X, the XK_Hyper_[LR] keysyms.  */
 340   shift_modifier=  CHAR_SHIFT,
 341   ctrl_modifier =  CHAR_CTL,
 342   meta_modifier =  CHAR_META    /* Under X, the XK_Meta_[LR] keysyms.  */
 343 };
 344
 345 #ifdef HAVE_GPM
 346 #include <gpm.h>
 347 extern int handle_one_term_event (struct tty_display_info *, Gpm_Event *, struct input_event *);
 348 #ifndef HAVE_WINDOW_SYSTEM
 349 extern void term_mouse_moveto (int, int);
 350 #endif
 351
 352 /* The device for which we have enabled gpm support.  */
 353 extern struct tty_display_info *gpm_tty;
 354 #endif
 355
 356 /* Terminal-local parameters. */
 357 struct terminal
 358 {
 359   /* This is for Lisp; the terminal code does not refer to it.  */
 360   struct vectorlike_header header;
 361
 362   /* Parameter alist of this terminal.  */
 363   Lisp_Object param_alist;
 364
 365   /* List of charsets supported by the terminal.  It is set by
 366      Fset_terminal_coding_system_internal along with
 367      the member terminal_coding.  */
 368   Lisp_Object charset_list;
 369
 370   /* This is an association list containing the X selections that
 371      Emacs might own on this terminal.  Each element has the form
 372        (SELECTION-NAME SELECTION-VALUE SELECTION-TIMESTAMP FRAME)
 373      SELECTION-NAME is a lisp symbol, whose name is the name of an X Atom.
 374      SELECTION-VALUE is the value that emacs owns for that selection.
 375       It may be any kind of Lisp object.
 376      SELECTION-TIMESTAMP is the time at which emacs began owning this
 377       selection, as a cons of two 16-bit numbers (making a 32 bit
 378       time.)
 379      FRAME is the frame for which we made the selection.  If there is
 380       an entry in this alist, then it can be assumed that Emacs owns
 381       that selection.
 382      The only (eq) parts of this list that are visible from Lisp are
 383     the selection-values.  */
 384   Lisp_Object Vselection_alist;
 385
 386   /* If a char-table, this maps characters to terminal glyph codes.
 387      If t, the mapping is not available.  If nil, it is not known
 388      whether the mapping is available.  */
 389   Lisp_Object glyph_code_table;
 390
 391   /* All fields before `next_terminal' should be Lisp_Object and are traced
 392      by the GC.  All fields afterwards are ignored by the GC.  */
 393
 394   /* Chain of all terminal devices. */
 395   struct terminal *next_terminal;
 396
 397   /* Unique id for this terminal device. */
 398   int id;
 399
 400   /* The number of frames that are on this terminal. */
 401   int reference_count;
 402
 403   /* The type of the terminal device. */
 404   enum output_method type;
 405
 406   /* The name of the terminal device.  Do not use this to uniquely
 407      identify a terminal; the same device may be opened multiple
 408      times. */
 409   char *name;
 410
 411   /* The terminal's keyboard object. */
 412   struct kboard *kboard;
 413
 414 #ifdef HAVE_WINDOW_SYSTEM
 415   /* Cache of images.  */
 416   struct image_cache *image_cache;
 417 #endif /* HAVE_WINDOW_SYSTEM */
 418
 419   /* Device-type dependent data shared amongst all frames on this terminal.  */
 420   union display_info
 421   {
 422     struct tty_display_info *tty;     /* termchar.h */
 423     struct x_display_info *x;         /* xterm.h */
 424     struct w32_display_info *w32;     /* w32term.h */
 425     struct ns_display_info *ns;       /* nsterm.h */
 426   } display_info;
 427
 428 \f
 429   /* Coding-system to be used for encoding terminal output.  This
 430      structure contains information of a coding-system specified by
 431      the function `set-terminal-coding-system'.  Also see
 432      `safe_terminal_coding' in coding.h.  */
 433   struct coding_system *terminal_coding;
 434
 435   /* Coding-system of what is sent from terminal keyboard.  This
 436      structure contains information of a coding-system specified by
 437      the function `set-keyboard-coding-system'.  */
 438   struct coding_system *keyboard_coding;
 439
 440   /* Window-based redisplay interface for this device (0 for tty
 441      devices). */
 442   struct redisplay_interface *rif;
 443
 444   /* Frame-based redisplay interface. */
 445
 446   /* Text display hooks.  */
 447
 448   void (*cursor_to_hook) (struct frame *f, int vpos, int hpos);
 449   void (*raw_cursor_to_hook) (struct frame *, int, int);
 450
 451   void (*clear_to_end_hook) (struct frame *);
 452   void (*clear_frame_hook) (struct frame *);
 453   void (*clear_end_of_line_hook) (struct frame *, int);
 454
 455   void (*ins_del_lines_hook) (struct frame *f, int, int);
 456
 457   void (*insert_glyphs_hook) (struct frame *f, struct glyph *s, int n);
 458   void (*write_glyphs_hook) (struct frame *f, struct glyph *s, int n);
 459   void (*delete_glyphs_hook) (struct frame *, int);
 460
 461   void (*ring_bell_hook) (struct frame *f);
 462   void (*toggle_invisible_pointer_hook) (struct frame *f, bool invisible);
 463
 464   void (*reset_terminal_modes_hook) (struct terminal *);
 465   void (*set_terminal_modes_hook) (struct terminal *);
 466
 467   void (*update_begin_hook) (struct frame *);
 468   void (*update_end_hook) (struct frame *);
 469   void (*set_terminal_window_hook) (struct frame *, int);
 470
 471   /* Multi-frame and mouse support hooks.  */
 472
 473   /* Return the current position of the mouse.
 474
 475      Set *f to the frame the mouse is in, or zero if the mouse is in no
 476      Emacs frame.  If it is set to zero, all the other arguments are
 477      garbage.
 478
 479      If the motion started in a scroll bar, set *bar_window to the
 480      scroll bar's window, *part to the part the mouse is currently over,
 481      *x to the position of the mouse along the scroll bar, and *y to the
 482      overall length of the scroll bar.
 483
 484      Otherwise, set *bar_window to Qnil, and *x and *y to the column and
 485      row of the character cell the mouse is over.
 486
 487      Set *time to the time the mouse was at the returned position.  */
 488   void (*mouse_position_hook) (struct frame **f, int,
 489                                Lisp_Object *bar_window,
 490                                enum scroll_bar_part *part,
 491                                Lisp_Object *x,
 492                                Lisp_Object *y,
 493                                Time *);
 494
 495   /* When a frame's focus redirection is changed, this hook tells the
 496      window system code to re-decide where to put the highlight.  Under
 497      X, this means that Emacs lies about where the focus is.  */
 498   void (*frame_rehighlight_hook) (struct frame *);
 499
 500   /* If we're displaying frames using a window system that can stack
 501      frames on top of each other, this hook allows you to bring a frame
 502      to the front, or bury it behind all the other windows.  If this
 503      hook is zero, that means the terminal we're displaying on doesn't
 504      support overlapping frames, so there's no need to raise or lower
 505      anything.
 506
 507      If RAISE_FLAG, F is brought to the front, before all other
 508      windows.  If !RAISE_FLAG, F is sent to the back, behind all other
 509      windows.  */
 510   void (*frame_raise_lower_hook) (struct frame *f, bool raise_flag);
 511
 512   /* If the value of the frame parameter changed, this hook is called.
 513      For example, if going from fullscreen to not fullscreen this hook
 514      may do something OS dependent, like extended window manager hints on X11.  */
 515   void (*fullscreen_hook) (struct frame *f);
 516
 517   /* This hook is called to display menus.  */
 518   Lisp_Object (*menu_show_hook) (struct frame *f, int x, int y, int menuflags,
 519                                  Lisp_Object title, const char **error_name);
 520
 521   /* This hook is called to display popup dialog.  */
 522   Lisp_Object (*popup_dialog_hook) (struct frame *f, Lisp_Object header,
 523                                     Lisp_Object contents);
 524
 525   /* Scroll bar hooks.  */
 526
 527   /* The representation of scroll bars is determined by the code which
 528      implements them, except for one thing: they must be represented by
 529      lisp objects.  This allows us to place references to them in
 530      Lisp_Windows without worrying about those references becoming
 531      dangling references when the scroll bar is destroyed.
 532
 533      The window-system-independent portion of Emacs just refers to
 534      scroll bars via their windows, and never looks inside the scroll bar
 535      representation; it always uses hook functions to do all the
 536      scroll bar manipulation it needs.
 537
 538      The `vertical_scroll_bar' field of a Lisp_Window refers to that
 539      window's scroll bar, or is nil if the window doesn't have a
 540      scroll bar.
 541
 542      The `scroll_bars' and `condemned_scroll_bars' fields of a Lisp_Frame
 543      are free for use by the scroll bar implementation in any way it sees
 544      fit.  They are marked by the garbage collector.  */
 545
 546
 547   /* Set the vertical scroll bar for WINDOW to have its upper left corner
 548      at (TOP, LEFT), and be LENGTH rows high.  Set its handle to
 549      indicate that we are displaying PORTION characters out of a total
 550      of WHOLE characters, starting at POSITION.  If WINDOW doesn't yet
 551      have a scroll bar, create one for it.  */
 552   void (*set_vertical_scroll_bar_hook) (struct window *window,
 553                                         int portion, int whole,
 554                                         int position);
 555
 556
 557   /* Set the horizontal scroll bar for WINDOW to have its upper left
 558      corner at (TOP, LEFT), and be LENGTH rows high.  Set its handle to
 559      indicate that we are displaying PORTION characters out of a total
 560      of WHOLE characters, starting at POSITION.  If WINDOW doesn't yet
 561      have a scroll bar, create one for it.  */
 562   void (*set_horizontal_scroll_bar_hook) (struct window *window,
 563                                           int portion, int whole,
 564                                           int position);
 565
 566
 567   /* The following three hooks are used when we're doing a thorough
 568      redisplay of the frame.  We don't explicitly know which scroll bars
 569      are going to be deleted, because keeping track of when windows go
 570      away is a real pain - can you say set-window-configuration?
 571      Instead, we just assert at the beginning of redisplay that *all*
 572      scroll bars are to be removed, and then save scroll bars from the
 573      fiery pit when we actually redisplay their window.  */
 574
 575   /* Arrange for all scroll bars on FRAME to be removed at the next call
 576      to `*judge_scroll_bars_hook'.  A scroll bar may be spared if
 577      `*redeem_scroll_bar_hook' is applied to its window before the judgment.
 578
 579      This should be applied to each frame each time its window tree is
 580      redisplayed, even if it is not displaying scroll bars at the moment;
 581      if the HAS_SCROLL_BARS flag has just been turned off, only calling
 582      this and the judge_scroll_bars_hook will get rid of them.
 583
 584      If non-zero, this hook should be safe to apply to any frame,
 585      whether or not it can support scroll bars, and whether or not it is
 586      currently displaying them.  */
 587   void (*condemn_scroll_bars_hook) (struct frame *frame);
 588
 589   /* Unmark WINDOW's scroll bar for deletion in this judgment cycle.
 590      Note that it's okay to redeem a scroll bar that is not condemned.  */
 591   void (*redeem_scroll_bar_hook) (struct window *window);
 592
 593   /* Remove all scroll bars on FRAME that haven't been saved since the
 594      last call to `*condemn_scroll_bars_hook'.
 595
 596      This should be applied to each frame after each time its window
 597      tree is redisplayed, even if it is not displaying scroll bars at the
 598      moment; if the HAS_SCROLL_BARS flag has just been turned off, only
 599      calling this and condemn_scroll_bars_hook will get rid of them.
 600
 601      If non-zero, this hook should be safe to apply to any frame,
 602      whether or not it can support scroll bars, and whether or not it is
 603      currently displaying them.  */
 604   void (*judge_scroll_bars_hook) (struct frame *FRAME);
 605
 606 \f
 607   /* Called to read input events.
 608
 609      TERMINAL indicates which terminal device to read from.  Input
 610      events should be read into HOLD_QUIT.
 611
 612      A positive return value indicates that that many input events
 613      were read into BUF.
 614      Zero means no events were immediately available.
 615      A value of -1 means a transient read error, while -2 indicates
 616      that the device was closed (hangup), and it should be deleted.  */
 617   int (*read_socket_hook) (struct terminal *terminal,
 618                            struct input_event *hold_quit);
 619
 620   /* Called when a frame's display becomes entirely up to date.  */
 621   void (*frame_up_to_date_hook) (struct frame *);
 622
 623 \f
 624   /* Called to delete the device-specific portions of a frame that is
 625      on this terminal device. */
 626   void (*delete_frame_hook) (struct frame *);
 627
 628   /* Called after the last frame on this terminal is deleted, or when
 629      the display device was closed (hangup).
 630
 631      If this is NULL, then the generic delete_terminal is called
 632      instead.  Otherwise the hook must call delete_terminal itself.
 633
 634      The hook must check for and close any live frames that are still
 635      on the terminal.  delete_frame ensures that there are no live
 636      frames on the terminal when it calls this hook, so infinite
 637      recursion is prevented.  */
 638   void (*delete_terminal_hook) (struct terminal *);
 639 };
 640
 641 /* Most code should use these functions to set Lisp fields in struct
 642    terminal.  */
 643 INLINE void
 644 tset_charset_list (struct terminal *t, Lisp_Object val)
 645 {
 646   t->charset_list = val;
 647 }
 648 INLINE void
 649 tset_selection_alist (struct terminal *t, Lisp_Object val)
 650 {
 651   t->Vselection_alist = val;
 652 }
 653
 654 /* Chain of all terminal devices currently in use.  */
 655 extern struct terminal *terminal_list;
 656
 657 #define FRAME_MUST_WRITE_SPACES(f) (FRAME_TTY (f)->must_write_spaces)
 658 #define FRAME_LINE_INS_DEL_OK(f) (FRAME_TTY (f)->line_ins_del_ok)
 659 #define FRAME_CHAR_INS_DEL_OK(f) (FRAME_TTY (f)->char_ins_del_ok)
 660 #define FRAME_SCROLL_REGION_OK(f) (FRAME_TTY (f)->scroll_region_ok)
 661 #define FRAME_SCROLL_REGION_COST(f) (FRAME_TTY (f)->scroll_region_cost)
 662 #define FRAME_MEMORY_BELOW_FRAME(f) (FRAME_TTY (f)->memory_below_frame)
 663
 664 #define FRAME_TERMINAL_CODING(f) ((f)->terminal->terminal_coding)
 665 #define FRAME_KEYBOARD_CODING(f) ((f)->terminal->keyboard_coding)
 666
 667 #define TERMINAL_TERMINAL_CODING(d) ((d)->terminal_coding)
 668 #define TERMINAL_KEYBOARD_CODING(d) ((d)->keyboard_coding)
 669
 670 #define FRAME_RIF(f) ((f)->terminal->rif)
 671
 672 #define FRAME_TERMINAL(f) ((f)->terminal)
 673
 674 /* Return true if the terminal device is not suspended.  */
 675 #define TERMINAL_ACTIVE_P(d)                                            \
 676   (((d)->type != output_termcap && (d)->type != output_msdos_raw)       \
 677    || (d)->display_info.tty->input)
 678
 679 /* Return font cache data for the specified terminal.  The historical
 680    name is grossly misleading, actually it is (NAME . FONT-LIST-CACHE).  */
 681 #if defined (HAVE_X_WINDOWS)
 682 #define TERMINAL_FONT_CACHE(t)                                          \
 683   (t->type == output_x_window ? t->display_info.x->name_list_element : Qnil)
 684 #elif defined (HAVE_NTGUI)
 685 #define TERMINAL_FONT_CACHE(t)                                          \
 686   (t->type == output_w32 ? t->display_info.w32->name_list_element : Qnil)
 687 #elif defined (HAVE_NS)
 688 #define TERMINAL_FONT_CACHE(t)                                          \
 689   (t->type == output_ns ? t->display_info.ns->name_list_element : Qnil)
 690 #endif
 691
 692 extern struct terminal *decode_live_terminal (Lisp_Object);
 693 extern struct terminal *decode_tty_terminal (Lisp_Object);
 694 extern struct terminal *get_named_terminal (const char *);
 695 extern struct terminal *create_terminal (enum output_method,
 696                                          struct redisplay_interface *);
 697 extern void delete_terminal (struct terminal *);
 698 extern Lisp_Object terminal_glyph_code (struct terminal *, int);
 699
 700 /* The initial terminal device, created by initial_term_init.  */
 701 extern struct terminal *initial_terminal;
 702
 703 extern unsigned char *encode_terminal_code (struct glyph *, int,
 704                                             struct coding_system *);
 705
 706 #ifdef HAVE_GPM
 707 extern void close_gpm (int gpm_fd);
 708 #endif
 709
 710 #ifdef WINDOWSNT
 711 extern int cursorX (struct tty_display_info *);
 712 extern int cursorY (struct tty_display_info *);
 713 #else
 714 #define cursorX(t)  curX(t)
 715 #define cursorY(t)  curY(t)
 716 #endif
 717
 718 INLINE_HEADER_END
 719
 720 #endif /* EMACS_TERMHOOKS_H */