src/termhooks.h

   1 /* Parameters and display hooks for terminal devices.
   2
   3 Copyright (C) 1985-1986, 1993-1994, 2001-2016 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 (at
  11 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 "lisp.h"
  27 #include "systime.h" /* for Time */
  28
  29 struct glyph;
  30
  31 INLINE_HEADER_BEGIN
  32
  33 enum scroll_bar_part {
  34   scroll_bar_nowhere,
  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   scroll_bar_before_handle,
  45   scroll_bar_horizontal_handle,
  46   scroll_bar_after_handle,
  47   scroll_bar_left_arrow,
  48   scroll_bar_right_arrow,
  49   scroll_bar_to_leftmost,
  50   scroll_bar_to_rightmost
  51 };
  52
  53 /* Output method of a terminal (and frames on this terminal, respectively).  */
  54
  55 enum output_method
  56 {
  57   output_initial,
  58   output_termcap,
  59   output_x_window,
  60   output_msdos_raw,
  61   output_w32,
  62   output_ns
  63 };
  64
  65 /* Input queue declarations and hooks.  */
  66
  67 enum event_kind
  68 {
  69   NO_EVENT,                     /* nothing happened.  This should never
  70                                    actually appear in the event queue.  */
  71
  72   ASCII_KEYSTROKE_EVENT,        /* The ASCII code is in .code, perhaps
  73                                    with modifiers applied.
  74                                    .modifiers holds the state of the
  75                                    modifier keys.
  76                                    .frame_or_window is the frame in
  77                                    which the key was typed.
  78                                    .timestamp gives a timestamp (in
  79                                    milliseconds) for the keystroke.  */
  80   MULTIBYTE_CHAR_KEYSTROKE_EVENT,       /* The multibyte char code is in .code,
  81                                    perhaps with modifiers applied.
  82                                    The others are the same as
  83                                    ASCII_KEYSTROKE_EVENT.  */
  84   NON_ASCII_KEYSTROKE_EVENT,    /* .code is a number identifying the
  85                                    function key.  A code N represents
  86                                    a key whose name is
  87                                    function_key_names[N]; function_key_names
  88                                    is a table in keyboard.c to which you
  89                                    should feel free to add missing keys.
  90                                    .modifiers holds the state of the
  91                                    modifier keys.
  92                                    .frame_or_window is the frame in
  93                                    which the key was typed.
  94                                    .timestamp gives a timestamp (in
  95                                    milliseconds) for the keystroke.  */
  96   TIMER_EVENT,                  /* A timer fired.  */
  97   MOUSE_CLICK_EVENT,            /* The button number is in .code; it must
  98                                    be >= 0 and < NUM_MOUSE_BUTTONS, defined
  99                                    below.
 100                                    .modifiers holds the state of the
 101                                    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 mouse click occurred in.
 106                                    .timestamp gives a timestamp (in
 107                                    milliseconds) for the click.  */
 108   WHEEL_EVENT,                  /* A wheel event is generated by a
 109                                    wheel on a mouse (e.g., MS
 110                                    Intellimouse).
 111                                    .modifiers holds the rotate
 112                                    direction (up or down), and the
 113                                    state of the modifier keys.
 114                                    .x and .y give the mouse position,
 115                                    in characters, within the window.
 116                                    .frame_or_window gives the frame
 117                                    the wheel event occurred in.
 118                                    .timestamp gives a timestamp (in
 119                                    milliseconds) for the event.  */
 120   HORIZ_WHEEL_EVENT,            /* A wheel event generated by a second
 121                                    horizontal wheel that is present on some
 122                                    mice. See WHEEL_EVENT.  */
 123 #ifdef HAVE_NTGUI
 124   LANGUAGE_CHANGE_EVENT,        /* A LANGUAGE_CHANGE_EVENT is
 125                                    generated when HAVE_NTGUI or on Mac OS
 126                                    when the keyboard layout or input
 127                                    language is changed by the
 128                                    user.  */
 129 #endif
 130   SCROLL_BAR_CLICK_EVENT,       /* .code gives the number of the mouse button
 131                                    that was clicked.
 132                                    .modifiers holds the state of the modifier
 133                                    keys.
 134                                    .part is a lisp symbol indicating which
 135                                    part of the scroll bar got clicked.
 136                                    .x gives the distance from the start of the
 137                                    scroll bar of the click; .y gives the total
 138                                    length of the scroll bar.
 139                                    .frame_or_window gives the window
 140                                    whose scroll bar was clicked in.
 141                                    .timestamp gives a timestamp (in
 142                                    milliseconds) for the click.  */
 143   HORIZONTAL_SCROLL_BAR_CLICK_EVENT,    /* .code gives the number of the mouse button
 144                                    that was clicked.
 145                                    .modifiers holds the state of the modifier
 146                                    keys.
 147                                    .part is a lisp symbol indicating which
 148                                    part of the scroll bar got clicked.
 149                                    .x gives the distance from the start of the
 150                                    scroll bar of the click; .y gives the total
 151                                    length of the scroll bar.
 152                                    .frame_or_window gives the window
 153                                    whose scroll bar was clicked in.
 154                                    .timestamp gives a timestamp (in
 155                                    milliseconds) for the click.  */
 156   SELECTION_REQUEST_EVENT,      /* Another X client wants a selection from us.
 157                                    See `struct selection_input_event'.  */
 158   SELECTION_CLEAR_EVENT,        /* Another X client cleared our selection.  */
 159   BUFFER_SWITCH_EVENT,          /* A process filter has switched buffers.  */
 160   DELETE_WINDOW_EVENT,          /* An X client said "delete this window".  */
 161 #ifdef HAVE_NTGUI
 162   END_SESSION_EVENT,            /* The user is logging out or shutting down.  */
 163 #endif
 164   MENU_BAR_EVENT,               /* An event generated by the menu bar.
 165                                    The frame_or_window field's cdr holds the
 166                                    Lisp-level event value.
 167                                    (Only the toolkit version uses these.)  */
 168   ICONIFY_EVENT,                /* An X client iconified this window.  */
 169   DEICONIFY_EVENT,              /* An X client deiconified this window.  */
 170   MENU_BAR_ACTIVATE_EVENT,      /* A button press in the menu bar
 171                                    (toolkit version only).  */
 172   DRAG_N_DROP_EVENT,            /* A drag-n-drop event is generated when
 173                                    files selected outside of Emacs are dropped
 174                                    onto an Emacs window.
 175                                    .modifiers holds the state of the
 176                                    modifier keys.
 177                                    .x and .y give the mouse position,
 178                                    in characters, within the window.
 179                                    .frame_or_window is the frame in
 180                                    which the drop was made.
 181                                    .arg is a platform-dependent
 182                                    representation of the dropped items.
 183                                    .timestamp gives a timestamp (in
 184                                    milliseconds) for the click.  */
 185   USER_SIGNAL_EVENT,            /* A user signal.
 186                                    code is a number identifying it,
 187                                    index into lispy_user_signals.  */
 188
 189   /* Help events.  Member `frame_or_window' of the input_event is the
 190      frame on which the event occurred, and member `arg' contains
 191      the help to show.  */
 192   HELP_EVENT,
 193
 194   /* An event from a tool-bar.  Member `arg' of the input event
 195      contains the tool-bar item selected.  If `frame_or_window'
 196      and `arg' are equal, this is a prefix event.  */
 197   TOOL_BAR_EVENT,
 198
 199   /* Queued from XTread_socket on FocusIn events.  Translated into
 200      `switch-frame' events in kbd_buffer_get_event, if necessary.  */
 201   FOCUS_IN_EVENT,
 202
 203   FOCUS_OUT_EVENT,
 204
 205   /* Generated when mouse moves over window not currently selected.  */
 206   SELECT_WINDOW_EVENT,
 207
 208   /* Queued from XTread_socket when session manager sends
 209      save yourself before shutdown. */
 210   SAVE_SESSION_EVENT
 211
 212 #ifdef HAVE_GPM
 213   , GPM_CLICK_EVENT
 214 #endif
 215
 216 #ifdef HAVE_DBUS
 217   , DBUS_EVENT
 218 #endif
 219
 220   , CONFIG_CHANGED_EVENT
 221
 222 #ifdef HAVE_NTGUI
 223   /* Generated when an APPCOMMAND event is received, in response to
 224      Multimedia or Internet buttons on some keyboards.
 225      Such keys are available as normal function keys on X through the
 226      Xkeyboard extension.
 227      On Windows, some of them get mapped to normal function key events,
 228      but others need to be handled by APPCOMMAND. Handling them all as
 229      APPCOMMAND events means they can be disabled
 230      (w32-pass-multimedia-buttons-to-system), important on Windows since
 231      the system never sees these keys if Emacs claims to handle them.
 232      On X, the window manager seems to grab the keys it wants
 233      first, so this is not a problem there.  */
 234   , MULTIMEDIA_KEY_EVENT
 235 #endif
 236
 237 #ifdef HAVE_NS
 238   /* Generated when native multi-keystroke input method is used to modify
 239      tentative or indicative text display. */
 240   , NS_TEXT_EVENT
 241   /* Non-key system events (e.g. application menu events) */
 242   , NS_NONKEY_EVENT
 243 #endif
 244
 245 #ifdef HAVE_XWIDGETS
 246   /* events generated by xwidgets*/
 247    , XWIDGET_EVENT
 248 #endif
 249
 250 #ifdef USE_FILE_NOTIFY
 251   /* File or directory was changed.  */
 252   , FILE_NOTIFY_EVENT
 253 #endif
 254
 255 };
 256
 257 /* Bit width of an enum event_kind tag at the start of structs and unions.  */
 258 enum { EVENT_KIND_WIDTH = 16 };
 259
 260 /* If a struct input_event has a kind which is SELECTION_REQUEST_EVENT
 261    or SELECTION_CLEAR_EVENT, then its contents are really described
 262    by `struct selection_input_event'; see xterm.h.  */
 263
 264 /* The keyboard input buffer is an array of these structures.  Each one
 265    represents some sort of input event - a keystroke, a mouse click, or
 266    a window system event.  These get turned into their lispy forms when
 267    they are removed from the event queue.  */
 268
 269 struct input_event
 270 {
 271   /* What kind of event was this?  */
 272   ENUM_BF (event_kind) kind : EVENT_KIND_WIDTH;
 273
 274   /* Used in scroll back click events.  */
 275   ENUM_BF (scroll_bar_part) part : 16;
 276
 277   /* For an ASCII_KEYSTROKE_EVENT and MULTIBYTE_CHAR_KEYSTROKE_EVENT,
 278      this is the character.
 279      For a NON_ASCII_KEYSTROKE_EVENT, this is the keysym code.
 280      For a mouse event, this is the button number.  */
 281   unsigned code;
 282
 283   /* See enum below for interpretation.  */
 284   unsigned modifiers;
 285
 286   /* One would prefer C integers, but HELP_EVENT uses these to
 287      record frame or window object and a help form, respectively.  */
 288   Lisp_Object x, y;
 289
 290   /* Usually a time as reported by window system-specific event loop.
 291      For a HELP_EVENT, this is the position within the object (stored
 292      in ARG below) where the help was found.  */
 293   Time timestamp;
 294
 295   /* This field is copied into a vector while the event is in
 296      the queue, so that garbage collections won't kill it.  */
 297   Lisp_Object frame_or_window;
 298
 299   /* This additional argument is used in attempt to avoid extra consing
 300      when building events.  Unfortunately some events have to pass much
 301      more data than it's reasonable to pack directly into this structure.  */
 302   Lisp_Object arg;
 303 };
 304
 305 #define EVENT_INIT(event) memset (&(event), 0, sizeof (struct input_event))
 306
 307 /* Bits in the modifiers member of the input_event structure.
 308    Note that reorder_modifiers assumes that the bits are in canonical
 309    order.
 310
 311    The modifiers applied to mouse clicks are rather ornate.  The
 312    window-system-specific code should store mouse clicks with
 313    up_modifier or down_modifier set.  Having an explicit down modifier
 314    simplifies some of window-system-independent code; without it, the
 315    code would have to recognize down events by checking if the event
 316    is a mouse click lacking the click and drag modifiers.
 317
 318    The window-system independent code turns all up_modifier events
 319    bits into drag_modifier, click_modifier, double_modifier, or
 320    triple_modifier events.  The click_modifier has no written
 321    representation in the names of the symbols used as event heads,
 322    but it does appear in the Qevent_symbol_components property of the
 323    event heads.  */
 324 enum {
 325   up_modifier   =   1,          /* Only used on mouse buttons - always
 326                                    turned into a click or a drag modifier
 327                                    before lisp code sees the event.  */
 328   down_modifier =   2,          /* Only used on mouse buttons.  */
 329   drag_modifier =   4,          /* This is never used in the event
 330                                    queue; it's only used internally by
 331                                    the window-system-independent code.  */
 332   click_modifier=   8,          /* See drag_modifier.  */
 333   double_modifier= 16,          /* See drag_modifier.  */
 334   triple_modifier= 32,          /* See drag_modifier.  */
 335
 336   /* The next four modifier bits are used also in keyboard events at
 337      the Lisp level.
 338
 339      It's probably not the greatest idea to use the 2^28 bit for any
 340      modifier.  It may or may not be the sign bit, depending on
 341      FIXNUM_BITS, so using it to represent a modifier key means that
 342      characters thus modified have different integer equivalents
 343      depending on the architecture they're running on.  Oh, and
 344      applying XINT to a character whose 2^28 bit is set might sign-extend
 345      it, so you get a bunch of bits in the mask you didn't want.
 346
 347      The CHAR_ macros are defined in lisp.h.  */
 348   alt_modifier  =  CHAR_ALT,    /* Under X, the XK_Alt_[LR] keysyms.  */
 349   super_modifier=  CHAR_SUPER,  /* Under X, the XK_Super_[LR] keysyms.  */
 350   hyper_modifier=  CHAR_HYPER,  /* Under X, the XK_Hyper_[LR] keysyms.  */
 351   shift_modifier=  CHAR_SHIFT,
 352   ctrl_modifier =  CHAR_CTL,
 353   meta_modifier =  CHAR_META    /* Under X, the XK_Meta_[LR] keysyms.  */
 354 };
 355
 356 #ifdef HAVE_GPM
 357 #include <gpm.h>
 358 extern int handle_one_term_event (struct tty_display_info *, Gpm_Event *, struct input_event *);
 359 #ifndef HAVE_WINDOW_SYSTEM
 360 extern void term_mouse_moveto (int, int);
 361 #endif
 362
 363 /* The device for which we have enabled gpm support.  */
 364 extern struct tty_display_info *gpm_tty;
 365 #endif
 366
 367 /* Terminal-local parameters. */
 368 struct terminal
 369 {
 370   /* This is for Lisp; the terminal code does not refer to it.  */
 371   struct vectorlike_header header;
 372
 373   /* Parameter alist of this terminal.  */
 374   Lisp_Object param_alist;
 375
 376   /* List of charsets supported by the terminal.  It is set by
 377      Fset_terminal_coding_system_internal along with
 378      the member terminal_coding.  */
 379   Lisp_Object charset_list;
 380
 381   /* This is an association list containing the X selections that
 382      Emacs might own on this terminal.  Each element has the form
 383        (SELECTION-NAME SELECTION-VALUE SELECTION-TIMESTAMP FRAME)
 384      SELECTION-NAME is a lisp symbol, whose name is the name of an X Atom.
 385      SELECTION-VALUE is the value that emacs owns for that selection.
 386       It may be any kind of Lisp object.
 387      SELECTION-TIMESTAMP is the time at which emacs began owning this
 388       selection, as a cons of two 16-bit numbers (making a 32 bit
 389       time.)
 390      FRAME is the frame for which we made the selection.  If there is
 391       an entry in this alist, then it can be assumed that Emacs owns
 392       that selection.
 393      The only (eq) parts of this list that are visible from Lisp are
 394     the selection-values.  */
 395   Lisp_Object Vselection_alist;
 396
 397   /* If a char-table, this maps characters to terminal glyph codes.
 398      If t, the mapping is not available.  If nil, it is not known
 399      whether the mapping is available.  */
 400   Lisp_Object glyph_code_table;
 401
 402   /* All fields before `next_terminal' should be Lisp_Object and are traced
 403      by the GC.  All fields afterwards are ignored by the GC.  */
 404
 405   /* Chain of all terminal devices. */
 406   struct terminal *next_terminal;
 407
 408   /* Unique id for this terminal device. */
 409   int id;
 410
 411   /* The number of frames that are on this terminal. */
 412   int reference_count;
 413
 414   /* The type of the terminal device. */
 415   enum output_method type;
 416
 417   /* The name of the terminal device.  Do not use this to uniquely
 418      identify a terminal; the same device may be opened multiple
 419      times. */
 420   char *name;
 421
 422   /* The terminal's keyboard object. */
 423   struct kboard *kboard;
 424
 425 #ifdef HAVE_WINDOW_SYSTEM
 426   /* Cache of images.  */
 427   struct image_cache *image_cache;
 428 #endif /* HAVE_WINDOW_SYSTEM */
 429
 430   /* Device-type dependent data shared amongst all frames on this terminal.  */
 431   union display_info
 432   {
 433     struct tty_display_info *tty;     /* termchar.h */
 434     struct x_display_info *x;         /* xterm.h */
 435     struct w32_display_info *w32;     /* w32term.h */
 436     struct ns_display_info *ns;       /* nsterm.h */
 437   } display_info;
 438
 439 \f
 440   /* Coding-system to be used for encoding terminal output.  This
 441      structure contains information of a coding-system specified by
 442      the function `set-terminal-coding-system'.  Also see
 443      `safe_terminal_coding' in coding.h.  */
 444   struct coding_system *terminal_coding;
 445
 446   /* Coding-system of what is sent from terminal keyboard.  This
 447      structure contains information of a coding-system specified by
 448      the function `set-keyboard-coding-system'.  */
 449   struct coding_system *keyboard_coding;
 450
 451   /* Window-based redisplay interface for this device (0 for tty
 452      devices). */
 453   struct redisplay_interface *rif;
 454
 455   /* Frame-based redisplay interface. */
 456
 457   /* Text display hooks.  */
 458
 459   void (*cursor_to_hook) (struct frame *f, int vpos, int hpos);
 460   void (*raw_cursor_to_hook) (struct frame *, int, int);
 461
 462   void (*clear_to_end_hook) (struct frame *);
 463   void (*clear_frame_hook) (struct frame *);
 464   void (*clear_end_of_line_hook) (struct frame *, int);
 465
 466   void (*ins_del_lines_hook) (struct frame *f, int, int);
 467
 468   void (*insert_glyphs_hook) (struct frame *f, struct glyph *s, int n);
 469   void (*write_glyphs_hook) (struct frame *f, struct glyph *s, int n);
 470   void (*delete_glyphs_hook) (struct frame *, int);
 471
 472   void (*ring_bell_hook) (struct frame *f);
 473   void (*toggle_invisible_pointer_hook) (struct frame *f, bool invisible);
 474
 475   void (*reset_terminal_modes_hook) (struct terminal *);
 476   void (*set_terminal_modes_hook) (struct terminal *);
 477
 478   void (*update_begin_hook) (struct frame *);
 479   void (*update_end_hook) (struct frame *);
 480   void (*set_terminal_window_hook) (struct frame *, int);
 481
 482   /* Multi-frame and mouse support hooks.  */
 483
 484   /* Return the current position of the mouse.
 485
 486      Set *f to the frame the mouse is in, or zero if the mouse is in no
 487      Emacs frame.  If it is set to zero, all the other arguments are
 488      garbage.
 489
 490      If the motion started in a scroll bar, set *bar_window to the
 491      scroll bar's window, *part to the part the mouse is currently over,
 492      *x to the position of the mouse along the scroll bar, and *y to the
 493      overall length of the scroll bar.
 494
 495      Otherwise, set *bar_window to Qnil, and *x and *y to the column and
 496      row of the character cell the mouse is over.
 497
 498      Set *time to the time the mouse was at the returned position.  */
 499   void (*mouse_position_hook) (struct frame **f, int,
 500                                Lisp_Object *bar_window,
 501                                enum scroll_bar_part *part,
 502                                Lisp_Object *x,
 503                                Lisp_Object *y,
 504                                Time *);
 505
 506   /* When a frame's focus redirection is changed, this hook tells the
 507      window system code to re-decide where to put the highlight.  Under
 508      X, this means that Emacs lies about where the focus is.  */
 509   void (*frame_rehighlight_hook) (struct frame *);
 510
 511   /* If we're displaying frames using a window system that can stack
 512      frames on top of each other, this hook allows you to bring a frame
 513      to the front, or bury it behind all the other windows.  If this
 514      hook is zero, that means the terminal we're displaying on doesn't
 515      support overlapping frames, so there's no need to raise or lower
 516      anything.
 517
 518      If RAISE_FLAG, F is brought to the front, before all other
 519      windows.  If !RAISE_FLAG, F is sent to the back, behind all other
 520      windows.  */
 521   void (*frame_raise_lower_hook) (struct frame *f, bool raise_flag);
 522
 523   /* If the value of the frame parameter changed, this hook is called.
 524      For example, if going from fullscreen to not fullscreen this hook
 525      may do something OS dependent, like extended window manager hints on X11.  */
 526   void (*fullscreen_hook) (struct frame *f);
 527
 528   /* This hook is called to display menus.  */
 529   Lisp_Object (*menu_show_hook) (struct frame *f, int x, int y, int menuflags,
 530                                  Lisp_Object title, const char **error_name);
 531
 532   /* This hook is called to display popup dialog.  */
 533   Lisp_Object (*popup_dialog_hook) (struct frame *f, Lisp_Object header,
 534                                     Lisp_Object contents);
 535
 536   /* Scroll bar hooks.  */
 537
 538   /* The representation of scroll bars is determined by the code which
 539      implements them, except for one thing: they must be represented by
 540      lisp objects.  This allows us to place references to them in
 541      Lisp_Windows without worrying about those references becoming
 542      dangling references when the scroll bar is destroyed.
 543
 544      The window-system-independent portion of Emacs just refers to
 545      scroll bars via their windows, and never looks inside the scroll bar
 546      representation; it always uses hook functions to do all the
 547      scroll bar manipulation it needs.
 548
 549      The `vertical_scroll_bar' field of a Lisp_Window refers to that
 550      window's scroll bar, or is nil if the window doesn't have a
 551      scroll bar.
 552
 553      The `scroll_bars' and `condemned_scroll_bars' fields of a Lisp_Frame
 554      are free for use by the scroll bar implementation in any way it sees
 555      fit.  They are marked by the garbage collector.  */
 556
 557
 558   /* Set the vertical scroll bar for WINDOW to have its upper left corner
 559      at (TOP, LEFT), and be LENGTH rows high.  Set its handle to
 560      indicate that we are displaying PORTION characters out of a total
 561      of WHOLE characters, starting at POSITION.  If WINDOW doesn't yet
 562      have a scroll bar, create one for it.  */
 563   void (*set_vertical_scroll_bar_hook) (struct window *window,
 564                                         int portion, int whole,
 565                                         int position);
 566
 567
 568   /* Set the horizontal scroll bar for WINDOW to have its upper left
 569      corner at (TOP, LEFT), and be LENGTH rows high.  Set its handle to
 570      indicate that we are displaying PORTION characters out of a total
 571      of WHOLE characters, starting at POSITION.  If WINDOW doesn't yet
 572      have a scroll bar, create one for it.  */
 573   void (*set_horizontal_scroll_bar_hook) (struct window *window,
 574                                           int portion, int whole,
 575                                           int position);
 576
 577
 578   /* The following three hooks are used when we're doing a thorough
 579      redisplay of the frame.  We don't explicitly know which scroll bars
 580      are going to be deleted, because keeping track of when windows go
 581      away is a real pain - can you say set-window-configuration?
 582      Instead, we just assert at the beginning of redisplay that *all*
 583      scroll bars are to be removed, and then save scroll bars from the
 584      fiery pit when we actually redisplay their window.  */
 585
 586   /* Arrange for all scroll bars on FRAME to be removed at the next call
 587      to `*judge_scroll_bars_hook'.  A scroll bar may be spared if
 588      `*redeem_scroll_bar_hook' is applied to its window before the judgment.
 589
 590      This should be applied to each frame each time its window tree is
 591      redisplayed, even if it is not displaying scroll bars at the moment;
 592      if the HAS_SCROLL_BARS flag has just been turned off, only calling
 593      this and the judge_scroll_bars_hook will get rid of them.
 594
 595      If non-zero, this hook should be safe to apply to any frame,
 596      whether or not it can support scroll bars, and whether or not it is
 597      currently displaying them.  */
 598   void (*condemn_scroll_bars_hook) (struct frame *frame);
 599
 600   /* Unmark WINDOW's scroll bar for deletion in this judgment cycle.
 601      Note that it's okay to redeem a scroll bar that is not condemned.  */
 602   void (*redeem_scroll_bar_hook) (struct window *window);
 603
 604   /* Remove all scroll bars on FRAME that haven't been saved since the
 605      last call to `*condemn_scroll_bars_hook'.
 606
 607      This should be applied to each frame after each time its window
 608      tree is redisplayed, even if it is not displaying scroll bars at the
 609      moment; if the HAS_SCROLL_BARS flag has just been turned off, only
 610      calling this and condemn_scroll_bars_hook will get rid of them.
 611
 612      If non-zero, this hook should be safe to apply to any frame,
 613      whether or not it can support scroll bars, and whether or not it is
 614      currently displaying them.  */
 615   void (*judge_scroll_bars_hook) (struct frame *FRAME);
 616
 617 \f
 618   /* Called to read input events.
 619
 620      TERMINAL indicates which terminal device to read from.  Input
 621      events should be read into HOLD_QUIT.
 622
 623      A positive return value indicates that that many input events
 624      were read into BUF.
 625      Zero means no events were immediately available.
 626      A value of -1 means a transient read error, while -2 indicates
 627      that the device was closed (hangup), and it should be deleted.  */
 628   int (*read_socket_hook) (struct terminal *terminal,
 629                            struct input_event *hold_quit);
 630
 631   /* Called when a frame's display becomes entirely up to date.  */
 632   void (*frame_up_to_date_hook) (struct frame *);
 633
 634   /* Called when buffer flipping becomes unblocked after having
 635      previously been blocked.  Redisplay always blocks buffer flips
 636      while it runs.  */
 637   void (*buffer_flipping_unblocked_hook) (struct frame *);
 638
 639 \f
 640   /* Called to delete the device-specific portions of a frame that is
 641      on this terminal device. */
 642   void (*delete_frame_hook) (struct frame *);
 643
 644   /* Called after the last frame on this terminal is deleted, or when
 645      the display device was closed (hangup).
 646
 647      If this is NULL, then the generic delete_terminal is called
 648      instead.  Otherwise the hook must call delete_terminal itself.
 649
 650      The hook must check for and close any live frames that are still
 651      on the terminal.  delete_frame ensures that there are no live
 652      frames on the terminal when it calls this hook, so infinite
 653      recursion is prevented.  */
 654   void (*delete_terminal_hook) (struct terminal *);
 655 };
 656
 657 /* Most code should use these functions to set Lisp fields in struct
 658    terminal.  */
 659 INLINE void
 660 tset_charset_list (struct terminal *t, Lisp_Object val)
 661 {
 662   t->charset_list = val;
 663 }
 664 INLINE void
 665 tset_selection_alist (struct terminal *t, Lisp_Object val)
 666 {
 667   t->Vselection_alist = val;
 668 }
 669
 670 /* Chain of all terminal devices currently in use.  */
 671 extern struct terminal *terminal_list;
 672
 673 #define FRAME_MUST_WRITE_SPACES(f) (FRAME_TTY (f)->must_write_spaces)
 674 #define FRAME_LINE_INS_DEL_OK(f) (FRAME_TTY (f)->line_ins_del_ok)
 675 #define FRAME_CHAR_INS_DEL_OK(f) (FRAME_TTY (f)->char_ins_del_ok)
 676 #define FRAME_SCROLL_REGION_OK(f) (FRAME_TTY (f)->scroll_region_ok)
 677 #define FRAME_SCROLL_REGION_COST(f) (FRAME_TTY (f)->scroll_region_cost)
 678 #define FRAME_MEMORY_BELOW_FRAME(f) (FRAME_TTY (f)->memory_below_frame)
 679
 680 #define FRAME_TERMINAL_CODING(f) ((f)->terminal->terminal_coding)
 681 #define FRAME_KEYBOARD_CODING(f) ((f)->terminal->keyboard_coding)
 682
 683 #define TERMINAL_TERMINAL_CODING(d) ((d)->terminal_coding)
 684 #define TERMINAL_KEYBOARD_CODING(d) ((d)->keyboard_coding)
 685
 686 #define FRAME_RIF(f) ((f)->terminal->rif)
 687
 688 #define FRAME_TERMINAL(f) ((f)->terminal)
 689
 690 /* Return true if the terminal device is not suspended.  */
 691 #define TERMINAL_ACTIVE_P(d)                                            \
 692   (((d)->type != output_termcap && (d)->type != output_msdos_raw)       \
 693    || (d)->display_info.tty->input)
 694
 695 /* Return font cache data for the specified terminal.  The historical
 696    name is grossly misleading, actually it is (NAME . FONT-LIST-CACHE).  */
 697 #if defined (HAVE_X_WINDOWS)
 698 #define TERMINAL_FONT_CACHE(t)                                          \
 699   (t->type == output_x_window ? t->display_info.x->name_list_element : Qnil)
 700 #elif defined (HAVE_NTGUI)
 701 #define TERMINAL_FONT_CACHE(t)                                          \
 702   (t->type == output_w32 ? t->display_info.w32->name_list_element : Qnil)
 703 #elif defined (HAVE_NS)
 704 #define TERMINAL_FONT_CACHE(t)                                          \
 705   (t->type == output_ns ? t->display_info.ns->name_list_element : Qnil)
 706 #endif
 707
 708 extern struct terminal *decode_live_terminal (Lisp_Object);
 709 extern struct terminal *decode_tty_terminal (Lisp_Object);
 710 extern struct terminal *get_named_terminal (const char *);
 711 extern struct terminal *create_terminal (enum output_method,
 712                                          struct redisplay_interface *);
 713 extern void delete_terminal (struct terminal *);
 714 extern Lisp_Object terminal_glyph_code (struct terminal *, int);
 715
 716 /* The initial terminal device, created by initial_term_init.  */
 717 extern struct terminal *initial_terminal;
 718
 719 extern unsigned char *encode_terminal_code (struct glyph *, int,
 720                                             struct coding_system *);
 721
 722 #ifdef HAVE_GPM
 723 extern void close_gpm (int gpm_fd);
 724 #endif
 725
 726 #ifdef WINDOWSNT
 727 extern int cursorX (struct tty_display_info *);
 728 extern int cursorY (struct tty_display_info *);
 729 #else
 730 #define cursorX(t)  curX(t)
 731 #define cursorY(t)  curY(t)
 732 #endif
 733
 734 INLINE_HEADER_END
 735
 736 #endif /* EMACS_TERMHOOKS_H */