(Fget_buffer_create): Disallow empty string.
[emacs.git] / src / termhooks.h
blobe20a8fea5ed1493938d0d5e05c27f9e2c0ea461a
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.
5 This file is part of GNU Emacs.
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.
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.
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. */
22 /* Miscellanea. */
24 /* If nonzero, send all terminal output characters to this stream also. */
25 extern FILE *termscript;
28 /* Text display hooks. */
30 extern int (*cursor_to_hook) ();
31 extern int (*raw_cursor_to_hook) ();
33 extern int (*clear_to_end_hook) ();
34 extern int (*clear_frame_hook) ();
35 extern int (*clear_end_of_line_hook) ();
37 extern int (*ins_del_lines_hook) ();
39 extern int (*change_line_highlight_hook) ();
40 extern int (*reassert_line_highlight_hook) ();
42 extern int (*insert_glyphs_hook) ();
43 extern int (*write_glyphs_hook) ();
44 extern int (*delete_glyphs_hook) ();
46 extern int (*ring_bell_hook) ();
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) ();
56 /* Multi-frame and mouse support hooks. */
58 enum scroll_bar_part {
59 scroll_bar_above_handle,
60 scroll_bar_handle,
61 scroll_bar_below_handle
64 /* Return the current position of the mouse.
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.
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.
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.
78 Set *time to the time the mouse was at the returned position.
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 */ );
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;
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 */ );
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.
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 */ );
112 /* Scroll bar hooks. */
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.
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.
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.
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. */
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 */ );
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. */
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.
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.
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 */ );
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 */ );
170 /* Remove all scroll bars on FRAME that haven't been saved since the
171 last call to `*condemn_scroll_bars_hook'.
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.
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 */ );
184 /* Input queue declarations and hooks. */
186 /* Called to read input events. */
187 extern int (*read_socket_hook) ();
189 /* Called when a frame's display becomes entirely up to date. */
190 extern int (*frame_up_to_date_hook) ();
192 /* Expedient hack: only provide the below definitions to files that
193 are prepared to handle lispy things. XINT is defined iff lisp.h
194 has been included before this file. */
195 #ifdef CONSP
197 enum event_kind
199 no_event, /* nothing happened. This should never
200 actually appear in the event queue. */
202 ascii_keystroke, /* The ASCII code is in .code, perhaps
203 with modifiers applied.
204 .modifiers holds the state of the
205 modifier keys.
206 .frame_or_window is the frame in
207 which the key was typed.
208 .timestamp gives a timestamp (in
209 milliseconds) for the keystroke. */
210 non_ascii_keystroke, /* .code is a number identifying the
211 function key. A code N represents
212 a key whose name is
213 function_key_names[N]; function_key_names
214 is a table in keyboard.c to which you
215 should feel free to add missing keys.
216 .modifiers holds the state of the
217 modifier keys.
218 .frame_or_window is the frame in
219 which the key was typed.
220 .timestamp gives a timestamp (in
221 milliseconds) for the keystroke. */
222 mouse_click, /* The button number is in .code; it must
223 be >= 0 and < NUM_MOUSE_BUTTONS, defined
224 below.
225 .modifiers holds the state of the
226 modifier keys.
227 .x and .y give the mouse position,
228 in characters, within the window.
229 .frame_or_window gives the frame
230 the mouse click occurred in.
231 .timestamp gives a timestamp (in
232 milliseconds) for the click. */
233 scroll_bar_click, /* .code gives the number of the mouse button
234 that was clicked.
235 .modifiers holds the state of the modifier
236 keys.
237 .part is a lisp symbol indicating which
238 part of the scroll bar got clicked.
239 .x gives the distance from the start of the
240 scroll bar of the click; .y gives the total
241 length of the scroll bar.
242 .frame_or_window gives the window
243 whose scroll bar was clicked in.
244 .timestamp gives a timestamp (in
245 milliseconds) for the click. */
246 selection_request_event, /* Another X client wants a selection from us.
247 See `struct selection_event'. */
248 selection_clear_event, /* Another X client cleared our selection. */
249 delete_window_event /* An X client said "delete this window". */
252 /* If a struct input_event has a kind which is selection_request_event
253 or selection_clear_event, then its contents are really described
254 by `struct selection_event'; see xterm.h. */
256 /* The keyboard input buffer is an array of these structures. Each one
257 represents some sort of input event - a keystroke, a mouse click, or
258 a window system event. These get turned into their lispy forms when
259 they are removed from the event queue. */
261 struct input_event {
263 /* What kind of event was this? */
264 enum event_kind kind;
266 /* For an ascii_keystroke, this is the character.
267 For a non_ascii_keystroke, this is the keysym code.
268 For a mouse event, this is the button number. */
269 int code;
270 enum scroll_bar_part part;
272 /* This field is copied into a vector while the event is in the queue,
273 so that garbage collections won't kill it. */
274 Lisp_Object frame_or_window;
276 int modifiers; /* See enum below for interpretation. */
278 Lisp_Object x, y;
279 unsigned long timestamp;
282 /* This is used in keyboard.c, to tell how many buttons we will need
283 to track the positions of. */
284 #define NUM_MOUSE_BUTTONS (5)
286 /* Bits in the modifiers member of the input_event structure.
287 Note that reorder_modifiers assumes that the bits are in canonical
288 order.
290 The modifiers applied to mouse clicks are rather ornate. The
291 window-system-specific code should store mouse clicks with
292 up_modifier or down_modifier set. Having an explicit down modifier
293 simplifies some of window-system-independent code; without it, the
294 code would have to recognize down events by checking if the event
295 is a mouse click lacking the click and drag modifiers.
297 The window-system independent code turns all up_modifier events
298 bits into drag_modifier, click_modifier, double_modifier, or
299 triple_modifier events. The click_modifier has no written
300 representation in the names of the symbols used as event heads,
301 but it does appear in the Qevent_symbol_components property of the
302 event heads. */
303 enum {
304 up_modifier = 1, /* Only used on mouse buttons - always
305 turned into a click or a drag modifier
306 before lisp code sees the event. */
307 down_modifier = 2, /* Only used on mouse buttons. */
308 drag_modifier = 4, /* This is never used in the event
309 queue; it's only used internally by
310 the window-system-independent code. */
311 click_modifier= 8, /* See drag_modifier. */
312 double_modifier= 16, /* See drag_modifier. */
313 triple_modifier= 32, /* See drag_modifier. */
315 /* The next four modifier bits are used also in keyboard events at
316 the Lisp level.
318 It's probably not the greatest idea to use the 2^23 bit for any
319 modifier. It may or may not be the sign bit, depending on
320 VALBITS, so using it to represent a modifier key means that
321 characters thus modified have different integer equivalents
322 depending on the architecture they're running on. Oh, and
323 applying XINT to a character whose 2^23 bit is set sign-extends
324 it, so you get a bunch of bits in the mask you didn't want.
326 The CHAR_ macros are defined in lisp.h. */
327 alt_modifier = CHAR_ALT, /* Under X, the XK_Alt_[LR] keysyms. */
328 super_modifier= CHAR_SUPER, /* Under X, the XK_Super_[LR] keysyms. */
329 hyper_modifier= CHAR_HYPER, /* Under X, the XK_Hyper_[LR] keysyms. */
330 shift_modifier= CHAR_SHIFT,
331 ctrl_modifier = CHAR_CTL,
332 meta_modifier = CHAR_META /* Under X, the XK_Meta_[LR] keysyms. */
335 #endif