src/termhooks.h

   1 /* Hooks by which low level terminal operations
   2    can be made to call other routines.
   3    Copyright (C) 1985, 1986, 1993 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 2, or (at your option)
  10 any later version.
  11
  12 GNU Emacs is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU Emacs; see the file COPYING.  If not, write to
  19 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  20
  21 \f
  22 /* Miscellanea.   */
  23
  24 /* If nonzero, send all terminal output characters to this stream also.  */
  25 extern FILE *termscript;
  26
  27 \f
  28 /* Text display hooks.  */
  29
  30 extern int (*cursor_to_hook) ();
  31 extern int (*raw_cursor_to_hook) ();
  32
  33 extern int (*clear_to_end_hook) ();
  34 extern int (*clear_frame_hook) ();
  35 extern int (*clear_end_of_line_hook) ();
  36
  37 extern int (*ins_del_lines_hook) ();
  38
  39 extern int (*change_line_highlight_hook) ();
  40 extern int (*reassert_line_highlight_hook) ();
  41
  42 extern int (*insert_glyphs_hook) ();
  43 extern int (*write_glyphs_hook) ();
  44 extern int (*delete_glyphs_hook) ();
  45
  46 extern int (*ring_bell_hook) ();
  47
  48 extern int (*reset_terminal_modes_hook) ();
  49 extern int (*set_terminal_modes_hook) ();
  50 extern int (*update_begin_hook) ();
  51 extern int (*update_end_hook) ();
  52 extern int (*set_terminal_window_hook) ();
  53
  54
  55 \f
  56 /* Multi-frame and mouse support hooks.  */
  57
  58 enum scroll_bar_part {
  59   scroll_bar_above_handle,
  60   scroll_bar_handle,
  61   scroll_bar_below_handle
  62 };
  63
  64 /* Return the current position of the mouse.
  65
  66    Set *f to the frame the mouse is in, or zero if the mouse is in no
  67    Emacs frame.  If it is set to zero, all the other arguments are
  68    garbage.
  69
  70    If the motion started in a scroll bar, set *bar_window to the
  71    scroll bar's window, *part to the part the mouse is currently over,
  72    *x to the position of the mouse along the scroll bar, and *y to the
  73    overall length of the scroll bar.
  74
  75    Otherwise, set *bar_window to Qnil, and *x and *y to the column and
  76    row of the character cell the mouse is over.
  77
  78    Set *time to the time the mouse was at the returned position.
  79
  80    This should clear mouse_moved until the next motion
  81    event arrives.  */
  82 extern void (*mouse_position_hook) ( /* FRAME_PTR *f,
  83                                         Lisp_Object *bar_window,
  84                                         enum scroll_bar_part *part,
  85                                         Lisp_Object *x,
  86                                         Lisp_Object *y,
  87                                         unsigned long *time */ );
  88
  89 /* The window system handling code should set this if the mouse has
  90    moved since the last call to the mouse_position_hook.  Calling that
  91    hook should clear this.  */
  92 extern int mouse_moved;
  93
  94 /* When a frame's focus redirection is changed, this hook tells the
  95    window system code to re-decide where to put the highlight.  Under
  96    X, this means that Emacs lies about where the focus is.  */
  97 extern void (*frame_rehighlight_hook) ( /* void */ );
  98
  99 /* If we're displaying frames using a window system that can stack
 100    frames on top of each other, this hook allows you to bring a frame
 101    to the front, or bury it behind all the other windows.  If this
 102    hook is zero, that means the device we're displaying on doesn't
 103    support overlapping frames, so there's no need to raise or lower
 104    anything.
 105
 106    If RAISE is non-zero, F is brought to the front, before all other
 107    windows.  If RAISE is zero, F is sent to the back, behind all other
 108    windows.  */
 109 extern void (*frame_raise_lower_hook) ( /* FRAME_PTR f, int raise */ );
 110
 111 \f
 112 /* Scroll bar hooks.  */
 113
 114 /* The representation of scroll bars is determined by the code which
 115    implements them, except for one thing: they must be represented by
 116    lisp objects.  This allows us to place references to them in
 117    Lisp_Windows without worrying about those references becoming
 118    dangling references when the scroll bar is destroyed.
 119
 120    The window-system-independent portion of Emacs just refers to
 121    scroll bars via their windows, and never looks inside the scroll bar
 122    representation; it always uses hook functions to do all the
 123    scroll bar manipulation it needs.
 124
 125    The `vertical_scroll_bar' field of a Lisp_Window refers to that
 126    window's scroll bar, or is nil if the window doesn't have a
 127    scroll bar.
 128
 129    The `scroll_bars' and `condemned_scroll_bars' fields of a Lisp_Frame
 130    are free for use by the scroll bar implementation in any way it sees
 131    fit.  They are marked by the garbage collector.  */
 132
 133
 134 /* Set the vertical scroll bar for WINDOW to have its upper left corner
 135    at (TOP, LEFT), and be LENGTH rows high.  Set its handle to
 136    indicate that we are displaying PORTION characters out of a total
 137    of WHOLE characters, starting at POSITION.  If WINDOW doesn't yet
 138    have a scroll bar, create one for it.  */
 139 extern void (*set_vertical_scroll_bar_hook)
 140             ( /* struct window *window,
 141                  int portion, int whole, int position */ );
 142
 143
 144 /* The following three hooks are used when we're doing a thorough
 145    redisplay of the frame.  We don't explicitly know which scroll bars
 146    are going to be deleted, because keeping track of when windows go
 147    away is a real pain - can you say set-window-configuration?
 148    Instead, we just assert at the beginning of redisplay that *all*
 149    scroll bars are to be removed, and then save scroll bars from the
 150    firey pit when we actually redisplay their window.  */
 151
 152 /* Arrange for all scroll bars on FRAME to be removed at the next call
 153    to `*judge_scroll_bars_hook'.  A scroll bar may be spared if
 154    `*redeem_scroll_bar_hook' is applied to its window before the judgement.
 155
 156    This should be applied to each frame each time its window tree is
 157    redisplayed, even if it is not displaying scroll bars at the moment;
 158    if the HAS_SCROLL_BARS flag has just been turned off, only calling
 159    this and the judge_scroll_bars_hook will get rid of them.
 160
 161    If non-zero, this hook should be safe to apply to any frame,
 162    whether or not it can support scroll bars, and whether or not it is
 163    currently displaying them.  */
 164 extern void (*condemn_scroll_bars_hook)( /* FRAME_PTR *frame */ );
 165
 166 /* Unmark WINDOW's scroll bar for deletion in this judgement cycle.
 167    Note that it's okay to redeem a scroll bar that is not condemned.  */
 168 extern void (*redeem_scroll_bar_hook)( /* struct window *window */ );
 169
 170 /* Remove all scroll bars on FRAME that haven't been saved since the
 171    last call to `*condemn_scroll_bars_hook'.
 172
 173    This should be applied to each frame after each time its window
 174    tree is redisplayed, even if it is not displaying scroll bars at the
 175    moment; if the HAS_SCROLL_BARS flag has just been turned off, only
 176    calling this and condemn_scroll_bars_hook will get rid of them.
 177
 178    If non-zero, this hook should be safe to apply to any frame,
 179    whether or not it can support scroll bars, and whether or not it is
 180    currently displaying them.  */
 181 extern void (*judge_scroll_bars_hook)( /* FRAME_PTR *FRAME */ );
 182
 183 \f
 184 /* Input queue declarations and hooks.  */
 185
 186 extern int (*read_socket_hook) ();
 187
 188 /* Expedient hack: only provide the below definitions to files that
 189    are prepared to handle lispy things.  XINT is defined iff lisp.h
 190    has been included before this file.  */
 191 #ifdef CONSP
 192
 193 enum event_kind
 194 {
 195   no_event,                     /* nothing happened.  This should never
 196                                    actually appear in the event queue.  */
 197   ascii_keystroke,              /* The ASCII code is in .code.
 198                                    .frame_or_window is the frame in
 199                                    which the key was typed.
 200                                    Note that this includes meta-keys, and
 201                                    the modifiers field of the event
 202                                    is unused.
 203                                    .timestamp gives a timestamp (in
 204                                    milliseconds) for the keystroke.  */
 205   non_ascii_keystroke,          /* .code is a number identifying the
 206                                    function key.  A code N represents
 207                                    a key whose name is
 208                                    function_key_names[N]; function_key_names
 209                                    is a table in keyboard.c to which you
 210                                    should feel free to add missing keys.
 211                                    .modifiers holds the state of the
 212                                    modifier keys.
 213                                    .frame_or_window is the frame in
 214                                    which the key was typed.
 215                                    .timestamp gives a timestamp (in
 216                                    milliseconds) for the keystroke.  */
 217   mouse_click,                  /* The button number is in .code; it must
 218                                    be >= 0 and < NUM_MOUSE_BUTTONS, defined
 219                                    below.
 220                                    .modifiers holds the state of the
 221                                    modifier keys.
 222                                    .x and .y give the mouse position,
 223                                    in characters, within the window.
 224                                    .frame_or_window gives the frame
 225                                    the mouse click occurred in.
 226                                    .timestamp gives a timestamp (in
 227                                    milliseconds) for the click.  */
 228   scroll_bar_click,             /* .code gives the number of the mouse button
 229                                    that was clicked.
 230                                    .modifiers holds the state of the modifier
 231                                    keys.
 232                                    .part is a lisp symbol indicating which
 233                                    part of the scroll bar got clicked.
 234                                    .x gives the distance from the start of the
 235                                    scroll bar of the click; .y gives the total
 236                                    length of the scroll bar.
 237                                    .frame_or_window gives the window
 238                                    whose scroll bar was clicked in.
 239                                    .timestamp gives a timestamp (in
 240                                    milliseconds) for the click.  */
 241   selection_request_event,      /* Another X client wants a selection from us.
 242                                    See `struct selection_event'.  */
 243   selection_clear_event         /* Another X client cleared our selection.  */
 244 };
 245
 246 /* If a struct input_event has a kind which is selection_request_event
 247    or selection_clear_event, then its contents are really described
 248    by `struct selection_event'; see xterm.h.  */
 249
 250 /* The keyboard input buffer is an array of these structures.  Each one
 251    represents some sort of input event - a keystroke, a mouse click, or
 252    a window system event.  These get turned into their lispy forms when
 253    they are removed from the event queue.  */
 254
 255 struct input_event {
 256
 257   /* What kind of event was this?  */
 258   enum event_kind kind;
 259
 260   Lisp_Object code;
 261   enum scroll_bar_part part;
 262
 263   /* This field is copied into a vector while the event is in the queue,
 264      so that garbage collections won't kill it.  */
 265   Lisp_Object frame_or_window;
 266
 267   int modifiers;                /* See enum below for interpretation.  */
 268
 269   Lisp_Object x, y;
 270   unsigned long timestamp;
 271 };
 272 \f
 273 /* This is used in keyboard.c, to tell how many buttons we will need
 274    to track the positions of.  */
 275 #define NUM_MOUSE_BUTTONS (5)
 276
 277 /* Bits in the modifiers member of the input_event structure.
 278    Note that reorder_modifiers assumes that the bits are in canonical
 279    order.
 280
 281    The modifiers applied to mouse clicks are rather ornate.  The
 282    window-system-specific code should store mouse clicks with
 283    up_modifier or down_modifier set.  Having an explicit down modifier
 284    simplifies some of window-system-independent code; without it, the
 285    code would have to recognize down events by checking if the event
 286    is a mouse click lacking the click and drag modifiers.
 287
 288    The window-system independent code turns all up_modifier events
 289    bits into drag_modifier, click_modifier, double_modifier, or
 290    triple_modifier events.  The click_modifier has no written
 291    representation in the names of the symbols used as event heads,
 292    but it does appear in the Qevent_symbol_components property of the
 293    event heads.  */
 294 enum {
 295   up_modifier   =   1,          /* Only used on mouse buttons - always
 296                                    turned into a click or a drag modifier
 297                                    before lisp code sees the event.  */
 298   down_modifier =   2,          /* Only used on mouse buttons.  */
 299   drag_modifier =   4,          /* This is never used in the event
 300                                    queue; it's only used internally by
 301                                    the window-system-independent code.  */
 302   click_modifier=   8,          /* See drag_modifier.  */
 303   double_modifier= 16,          /* See drag_modifier.  */
 304   triple_modifier= 32,          /* See drag_modifier.  */
 305
 306   /* The next four modifier bits are used also in keyboard events at
 307      the Lisp level.
 308
 309      It's probably not the greatest idea to use the 2^23 bit for any
 310      modifier.  It may or may not be the sign bit, depending on
 311      VALBITS, so using it to represent a modifier key means that
 312      characters thus modified have different integer equivalents
 313      depending on the architecture they're running on.  Oh, and
 314      applying XINT to a character whose 2^23 bit is set sign-extends
 315      it, so you get a bunch of bits in the mask you didn't want.
 316
 317      The CHAR_ macros are defined in lisp.h.  */
 318   alt_modifier  =  CHAR_ALT,    /* Under X, the XK_Alt_[LR] keysyms.  */
 319   super_modifier=  CHAR_SUPER,  /* Under X, the XK_Super_[LR] keysyms.  */
 320   hyper_modifier=  CHAR_HYPER,  /* Under X, the XK_Hyper_[LR] keysyms.  */
 321   shift_modifier=  CHAR_SHIFT,
 322   ctrl_modifier =  CHAR_CTL,
 323   meta_modifier =  CHAR_META    /* Under X, the XK_Meta_[LR] keysyms.  */
 324 };
 325
 326 #endif