keyboard.c 370 KB
Newer Older
Jim Blandy's avatar
Jim Blandy committed
1
/* Keyboard and mouse input; editor command loop.
2

3
Copyright (C) 1985-1989, 1993-1997, 1999-2012  Free Software Foundation, Inc.
Jim Blandy's avatar
Jim Blandy committed
4 5 6

This file is part of GNU Emacs.

7
GNU Emacs is free software: you can redistribute it and/or modify
Jim Blandy's avatar
Jim Blandy committed
8
it under the terms of the GNU General Public License as published by
9 10
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Jim Blandy's avatar
Jim Blandy committed
11 12 13 14 15 16 17

GNU Emacs is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
18
along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
Jim Blandy's avatar
Jim Blandy committed
19

20
#include <config.h>
Paul Eggert's avatar
Paul Eggert committed
21 22 23

#define KEYBOARD_INLINE EXTERN_INLINE

Jim Blandy's avatar
Jim Blandy committed
24
#include <stdio.h>
25

26
#include "lisp.h"
Jim Blandy's avatar
Jim Blandy committed
27 28
#include "termchar.h"
#include "termopts.h"
29
#include "frame.h"
Jim Blandy's avatar
Jim Blandy committed
30 31
#include "termhooks.h"
#include "macros.h"
32
#include "keyboard.h"
Jim Blandy's avatar
Jim Blandy committed
33 34
#include "window.h"
#include "commands.h"
35
#include "character.h"
36
#include "buffer.h"
Jim Blandy's avatar
Jim Blandy committed
37
#include "disptab.h"
38
#include "dispextern.h"
Richard M. Stallman's avatar
Richard M. Stallman committed
39
#include "syntax.h"
Richard M. Stallman's avatar
Richard M. Stallman committed
40
#include "intervals.h"
Stefan Monnier's avatar
Stefan Monnier committed
41
#include "keymap.h"
42
#include "blockinput.h"
43
#include "puresize.h"
44 45
#include "systime.h"
#include "atimer.h"
46
#include "process.h"
Jim Blandy's avatar
Jim Blandy committed
47 48
#include <errno.h>

49
#ifdef HAVE_PTHREAD
50 51
#include <pthread.h>
#endif
52 53 54 55
#ifdef MSDOS
#include "msdos.h"
#include <time.h>
#else /* not MSDOS */
Jim Blandy's avatar
Jim Blandy committed
56
#include <sys/ioctl.h>
57
#endif /* not MSDOS */
Jim Blandy's avatar
Jim Blandy committed
58

Paul Eggert's avatar
Paul Eggert committed
59 60 61 62
#if defined USABLE_FIONREAD && defined USG5_4
# include <sys/filio.h>
#endif

Jim Blandy's avatar
Jim Blandy committed
63 64
#include "syssignal.h"

65 66
#include <sys/types.h>
#include <unistd.h>
67 68
#include <fcntl.h>

69 70 71
#ifdef HAVE_WINDOW_SYSTEM
#include TERM_HEADER
#endif /* HAVE_WINDOW_SYSTEM */
72

73
/* Variables for blockinput.h: */
74 75

/* Non-zero if interrupt input is blocked right now.  */
76
volatile int interrupt_input_blocked;
77 78 79

/* Nonzero means an input interrupt has arrived
   during the current critical section.  */
80
int interrupt_input_pending;
81

Chong Yidong's avatar
Chong Yidong committed
82 83 84 85 86 87 88
/* This var should be (interrupt_input_pending || pending_atimers).
   The QUIT macro checks this instead of interrupt_input_pending and
   pending_atimers separately, to reduce code size.  So, any code that
   changes interrupt_input_pending or pending_atimers should update
   this too.  */
int pending_signals;

89
#define KBD_BUFFER_SIZE 4096
Jim Blandy's avatar
Jim Blandy committed
90

91 92 93
KBOARD *initial_kboard;
KBOARD *current_kboard;
KBOARD *all_kboards;
94 95 96

/* Nonzero in the single-kboard state, 0 in the any-kboard state.  */
static int single_kboard;
97

Jim Blandy's avatar
Jim Blandy committed
98
/* Non-nil disable property on a command means
99
   do not execute it; call disabled-command-function's value instead.  */
100 101
Lisp_Object Qdisabled;
static Lisp_Object Qdisabled_command_function;
Jim Blandy's avatar
Jim Blandy committed
102

103
#define NUM_RECENT_KEYS (300)
104 105 106 107 108 109 110 111 112

/* Index for storing next element into recent_keys.  */
static int recent_keys_index;

/* Total number of elements stored into recent_keys.  */
static int total_keys;

/* This vector holds the last NUM_RECENT_KEYS keystrokes.  */
static Lisp_Object recent_keys;
Jim Blandy's avatar
Jim Blandy committed
113

114 115 116 117 118 119
/* Vector holding the key sequence that invoked the current command.
   It is reused for each command, and it may be longer than the current
   sequence; this_command_key_count indicates how many elements
   actually mean something.
   It's easier to staticpro a single Lisp_Object than an array.  */
Lisp_Object this_command_keys;
120
ptrdiff_t this_command_key_count;
Jim Blandy's avatar
Jim Blandy committed
121

122 123
/* 1 after calling Freset_this_command_lengths.
   Usually it is 0.  */
124
static int this_command_key_count_reset;
125

126 127
/* This vector is used as a buffer to record the events that were actually read
   by read_key_sequence.  */
128 129
static Lisp_Object raw_keybuf;
static int raw_keybuf_count;
130 131

#define GROW_RAW_KEYBUF							\
132
 if (raw_keybuf_count == ASIZE (raw_keybuf))				\
133
   raw_keybuf = larger_vector (raw_keybuf, 1, -1)
134

135 136
/* Number of elements of this_command_keys
   that precede this key sequence.  */
137
static ptrdiff_t this_single_command_key_start;
138

139 140
/* Record values of this_command_key_count and echo_length ()
   before this command was read.  */
141 142
static ptrdiff_t before_command_key_count;
static ptrdiff_t before_command_echo_length;
143

Jim Blandy's avatar
Jim Blandy committed
144
/* For longjmp to where kbd input is being done.  */
145

146
static sys_jmp_buf getcjmp;
Jim Blandy's avatar
Jim Blandy committed
147 148 149 150 151

/* True while doing kbd input.  */
int waiting_for_input;

/* True while displaying for echoing.   Delays C-g throwing.  */
152

153
static int echoing;
Jim Blandy's avatar
Jim Blandy committed
154

155 156 157 158 159
/* Non-null means we can start echoing at the next input pause even
   though there is something in the echo area.  */

static struct kboard *ok_to_echo_at_next_pause;

160 161 162 163
/* The kboard last echoing, or null for none.  Reset to 0 in
   cancel_echoing.  If non-null, and a current echo area message
   exists, and echo_message_buffer is eq to the current message
   buffer, we know that the message comes from echo_kboard.  */
164

165
struct kboard *echo_kboard;
166

167 168 169
/* The buffer used for echoing.  Set in echo_now, reset in
   cancel_echoing.  */

170
Lisp_Object echo_message_buffer;
171

172
/* Nonzero means C-g should cause immediate error-signal.  */
Jim Blandy's avatar
Jim Blandy committed
173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193
int immediate_quit;

/* Character that causes a quit.  Normally C-g.

   If we are running on an ordinary terminal, this must be an ordinary
   ASCII char, since we want to make it our interrupt character.

   If we are not running on an ordinary terminal, it still needs to be
   an ordinary ASCII char.  This character needs to be recognized in
   the input interrupt handler.  At this point, the keystroke is
   represented as a struct input_event, while the desired quit
   character is specified as a lispy event.  The mapping from struct
   input_events to lispy events cannot run in an interrupt handler,
   and the reverse mapping is difficult for anything but ASCII
   keystrokes.

   FOR THESE ELABORATE AND UNSATISFYING REASONS, quit_char must be an
   ASCII character.  */
int quit_char;

/* Current depth in recursive edits.  */
194
EMACS_INT command_loop_level;
Jim Blandy's avatar
Jim Blandy committed
195

196 197
/* If not Qnil, this is a switch-frame event which we decided to put
   off until the end of a key sequence.  This should be read as the
Jim Blandy's avatar
Jim Blandy committed
198
   next command input, after any unread_command_events.
199 200 201 202 203

   read_key_sequence uses this to delay switch-frame events until the
   end of the key sequence; Fread_char uses it to put off switch-frame
   events until a non-ASCII event is acceptable as input.  */
Lisp_Object unread_switch_frame;
204

Jim Blandy's avatar
Jim Blandy committed
205
/* Last size recorded for a current buffer which is not a minibuffer.  */
206
static ptrdiff_t last_non_minibuf_size;
Jim Blandy's avatar
Jim Blandy committed
207

208 209
/* Total number of times read_char has returned, modulo UINTMAX_MAX + 1.  */
uintmax_t num_input_events;
Jim Blandy's avatar
Jim Blandy committed
210

211
/* Value of num_nonmacro_input_events as of last auto save.  */
Jim Blandy's avatar
Jim Blandy committed
212

213
static EMACS_INT last_auto_save;
Jim Blandy's avatar
Jim Blandy committed
214

215
/* The value of point when the last command was started.  */
216
static ptrdiff_t last_point_position;
217

218
/* The buffer that was current when the last command was started.  */
219
static Lisp_Object last_point_position_buffer;
220

221
/* The window that was selected when the last command was started.  */
222
static Lisp_Object last_point_position_window;
223

224 225 226 227 228 229 230
/* The frame in which the last input event occurred, or Qmacro if the
   last event came from a macro.  We use this to determine when to
   generate switch-frame events.  This may be cleared by functions
   like Fselect_frame, to make sure that a switch-frame event is
   generated by the next character.  */
Lisp_Object internal_last_event_frame;

Jim Blandy's avatar
Jim Blandy committed
231 232
/* The timestamp of the last input event we received from the X server.
   X Windows wants this for selection ownership.  */
233
Time last_event_timestamp;
Jim Blandy's avatar
Jim Blandy committed
234

235
static Lisp_Object Qx_set_selection, Qhandle_switch_frame;
236
static Lisp_Object Qhandle_select_window;
237
Lisp_Object QPRIMARY;
238

239 240 241
static Lisp_Object Qself_insert_command;
static Lisp_Object Qforward_char;
static Lisp_Object Qbackward_char;
242
Lisp_Object Qundefined;
243
static Lisp_Object Qtimer_event_handler;
Jim Blandy's avatar
Jim Blandy committed
244 245 246

/* read_key_sequence stores here the command definition of the
   key sequence that it reads.  */
247
static Lisp_Object read_key_sequence_cmd;
248
static Lisp_Object read_key_sequence_remapped;
Jim Blandy's avatar
Jim Blandy committed
249

250
static Lisp_Object Qinput_method_function;
251

252
static Lisp_Object Qdeactivate_mark;
253

254 255
Lisp_Object Qrecompute_lucid_menubar, Qactivate_menubar_hook;

256
static Lisp_Object Qecho_area_clear_hook;
257

258
/* Hooks to run before and after each command.  */
259 260
static Lisp_Object Qpre_command_hook;
static Lisp_Object Qpost_command_hook;
261

262
static Lisp_Object Qdeferred_action_function;
263

264 265
static Lisp_Object Qdelayed_warnings_hook;

266 267
static Lisp_Object Qinput_method_exit_on_first_char;
static Lisp_Object Qinput_method_use_echo_area;
268

269
static Lisp_Object Qhelp_form_show;
270

Jim Blandy's avatar
Jim Blandy committed
271
/* File in which we write all commands we read.  */
272
static FILE *dribble;
Jim Blandy's avatar
Jim Blandy committed
273 274 275 276

/* Nonzero if input is available.  */
int input_pending;

277
/* Circular buffer for pre-read keyboard input.  */
278

279 280 281 282
static struct input_event kbd_buffer[KBD_BUFFER_SIZE];

/* Pointer to next available character in kbd_buffer.
   If kbd_fetch_ptr == kbd_store_ptr, the buffer is empty.
283
   This may be kbd_buffer + KBD_BUFFER_SIZE, meaning that the
284 285 286 287 288 289
   next available char is in kbd_buffer[0].  */
static struct input_event *kbd_fetch_ptr;

/* Pointer to next place to store character in kbd_buffer.  This
   may be kbd_buffer + KBD_BUFFER_SIZE, meaning that the next
   character should go in kbd_buffer[0].  */
290
static struct input_event * volatile kbd_store_ptr;
291 292 293 294

/* The above pair of variables forms a "queue empty" flag.  When we
   enqueue a non-hook event, we increment kbd_store_ptr.  When we
   dequeue a non-hook event, we increment kbd_fetch_ptr.  We say that
Glenn Morris's avatar
Glenn Morris committed
295
   there is input available if the two pointers are not equal.
296 297 298 299 300

   Why not just have a flag set and cleared by the enqueuing and
   dequeuing functions?  Such a flag could be screwed up by interrupts
   at inopportune times.  */

Jim Blandy's avatar
Jim Blandy committed
301
/* Symbols to head events.  */
302 303
static Lisp_Object Qmouse_movement;
static Lisp_Object Qscroll_bar_movement;
304
Lisp_Object Qswitch_frame;
305 306 307 308
static Lisp_Object Qdelete_frame;
static Lisp_Object Qiconify_frame;
static Lisp_Object Qmake_frame_visible;
static Lisp_Object Qselect_window;
309
Lisp_Object Qhelp_echo;
310

Nick Roberts's avatar
Nick Roberts committed
311
#if defined (HAVE_MOUSE) || defined (HAVE_GPM)
312
static Lisp_Object Qmouse_fixup_help_message;
313 314
#endif

Jim Blandy's avatar
Jim Blandy committed
315
/* Symbols to denote kinds of events.  */
316
static Lisp_Object Qfunction_key;
Jim Blandy's avatar
Jim Blandy committed
317
Lisp_Object Qmouse_click;
318
#if defined (WINDOWSNT)
319
Lisp_Object Qlanguage_change;
320
#endif
321 322
static Lisp_Object Qdrag_n_drop;
static Lisp_Object Qsave_session;
323
#ifdef HAVE_DBUS
324
static Lisp_Object Qdbus_event;
325
#endif
326
static Lisp_Object Qconfig_changed_event;
327

Jim Blandy's avatar
Jim Blandy committed
328 329 330 331
/* Lisp_Object Qmouse_movement; - also an event header */

/* Properties of event headers.  */
Lisp_Object Qevent_kind;
332
static Lisp_Object Qevent_symbol_elements;
Jim Blandy's avatar
Jim Blandy committed
333

334
/* Menu and tool bar item parts.  */
335 336 337 338 339 340 341 342 343 344
static Lisp_Object Qmenu_enable;
static Lisp_Object QCenable, QCvisible, QChelp, QCkeys, QCkey_sequence;
Lisp_Object QCfilter;

/* Non-nil disable property on a command means
   do not execute it; call disabled-command-function's value instead.  */
Lisp_Object QCtoggle, QCradio;
static Lisp_Object QCbutton, QClabel;

static Lisp_Object QCvert_only;
345

346 347 348 349 350 351 352 353 354 355 356
/* An event header symbol HEAD may have a property named
   Qevent_symbol_element_mask, which is of the form (BASE MODIFIERS);
   BASE is the base, unmodified version of HEAD, and MODIFIERS is the
   mask of modifiers applied to it.  If present, this is used to help
   speed up parse_modifiers.  */
Lisp_Object Qevent_symbol_element_mask;

/* An unmodified event header BASE may have a property named
   Qmodifier_cache, which is an alist mapping modifier masks onto
   modified versions of BASE.  If present, this helps speed up
   apply_modifiers.  */
357
static Lisp_Object Qmodifier_cache;
358

359
/* Symbols to use for parts of windows.  */
Jim Blandy's avatar
Jim Blandy committed
360
Lisp_Object Qmode_line;
Jim Blandy's avatar
Jim Blandy committed
361
Lisp_Object Qvertical_line;
362
static Lisp_Object Qvertical_scroll_bar;
363 364
Lisp_Object Qmenu_bar;

365 366
static Lisp_Object recursive_edit_unwind (Lisp_Object buffer);
static Lisp_Object command_loop (void);
367
static Lisp_Object Qextended_command_history;
368
EMACS_TIME timer_check (void);
Jim Blandy's avatar
Jim Blandy committed
369

370
static void record_menu_key (Lisp_Object c);
371
static void echo_now (void);
372
static ptrdiff_t echo_length (void);
373

374
static Lisp_Object Qpolling_period;
375

376 377 378
/* Incremented whenever a timer is run.  */
int timers_run;

Jim Blandy's avatar
Jim Blandy committed
379 380 381
/* Address (if not 0) of EMACS_TIME to zero out if a SIGIO interrupt
   happens.  */
EMACS_TIME *input_available_clear_time;
Jim Blandy's avatar
Jim Blandy committed
382 383 384 385 386 387 388 389

/* Nonzero means use SIGIO interrupts; zero means use CBREAK mode.
   Default is 1 if INTERRUPT_INPUT is defined.  */
int interrupt_input;

/* Nonzero while interrupts are temporarily deferred during redisplay.  */
int interrupts_deferred;

390
/* If we support a window system, turn on the code to poll periodically
391
   to detect C-g.  It isn't actually used when doing interrupt input.  */
Juanma Barranquero's avatar
Juanma Barranquero committed
392
#if defined (HAVE_WINDOW_SYSTEM) && !defined (USE_ASYNC_EVENTS)
Jim Blandy's avatar
Jim Blandy committed
393 394
#define POLL_FOR_INPUT
#endif
395

396 397 398 399
/* The time when Emacs started being idle.  */

static EMACS_TIME timer_idleness_start_time;

400 401 402 403 404
/* After Emacs stops being idle, this saves the last value
   of timer_idleness_start_time from when it was idle.  */

static EMACS_TIME timer_last_idleness_start_time;

Jim Blandy's avatar
Jim Blandy committed
405 406 407

/* Global variable declarations.  */

408 409 410 411 412
/* Flags for readable_events.  */
#define READABLE_EVENTS_DO_TIMERS_NOW		(1 << 0)
#define READABLE_EVENTS_FILTER_EVENTS		(1 << 1)
#define READABLE_EVENTS_IGNORE_SQUEEZABLES	(1 << 2)

Jim Blandy's avatar
Jim Blandy committed
413
/* Function for init_keyboard to call with no args (if nonzero).  */
414
static void (*keyboard_init_hook) (void);
Jim Blandy's avatar
Jim Blandy committed
415

416 417 418
static int read_avail_input (int);
static void get_input_pending (int *, int);
static int readable_events (int);
419
static Lisp_Object read_char_x_menu_prompt (ptrdiff_t, Lisp_Object *,
420
                                            Lisp_Object, int *);
421
static Lisp_Object read_char_minibuf_menu_prompt (int, ptrdiff_t,
422 423
                                                  Lisp_Object *);
static Lisp_Object make_lispy_event (struct input_event *);
Nick Roberts's avatar
Nick Roberts committed
424
#if defined (HAVE_MOUSE) || defined (HAVE_GPM)
425 426 427
static Lisp_Object make_lispy_movement (struct frame *, Lisp_Object,
                                        enum scroll_bar_part,
                                        Lisp_Object, Lisp_Object,
428
					Time);
429
#endif
430
static Lisp_Object modify_event_symbol (ptrdiff_t, int, Lisp_Object,
431
                                        Lisp_Object, const char *const *,
432
                                        Lisp_Object *, ptrdiff_t);
433
static Lisp_Object make_lispy_switch_frame (Lisp_Object);
434
static int help_char_p (Lisp_Object);
435 436
static void save_getcjmp (sys_jmp_buf);
static void restore_getcjmp (sys_jmp_buf);
437 438 439
static Lisp_Object apply_modifiers (int, Lisp_Object);
static void clear_event (struct input_event *);
static Lisp_Object restore_kboard_configuration (Lisp_Object);
Paul Eggert's avatar
Paul Eggert committed
440
#ifdef USABLE_SIGIO
441
static void deliver_input_available_signal (int signo);
442
#endif
443
static void handle_interrupt (void);
444
static _Noreturn void quit_throw_to_read_char (int);
445
static void process_special_events (void);
446 447 448
static void timer_start_idle (void);
static void timer_stop_idle (void);
static void timer_resume_idle (void);
449
static void deliver_user_signal (int);
450 451
static char *find_user_signal_name (int);
static int store_user_signal_events (void);
Jim Blandy's avatar
Jim Blandy committed
452

Paul Eggert's avatar
Paul Eggert committed
453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499
/* These setters are used only in this file, so they can be private.  */
static inline void
kset_echo_string (struct kboard *kb, Lisp_Object val)
{
  kb->INTERNAL_FIELD (echo_string) = val;
}
static inline void
kset_kbd_queue (struct kboard *kb, Lisp_Object val)
{
  kb->INTERNAL_FIELD (kbd_queue) = val;
}
static inline void
kset_keyboard_translate_table (struct kboard *kb, Lisp_Object val)
{
  kb->INTERNAL_FIELD (Vkeyboard_translate_table) = val;
}
static inline void
kset_last_prefix_arg (struct kboard *kb, Lisp_Object val)
{
  kb->INTERNAL_FIELD (Vlast_prefix_arg) = val;
}
static inline void
kset_last_repeatable_command (struct kboard *kb, Lisp_Object val)
{
  kb->INTERNAL_FIELD (Vlast_repeatable_command) = val;
}
static inline void
kset_local_function_key_map (struct kboard *kb, Lisp_Object val)
{
  kb->INTERNAL_FIELD (Vlocal_function_key_map) = val;
}
static inline void
kset_overriding_terminal_local_map (struct kboard *kb, Lisp_Object val)
{
  kb->INTERNAL_FIELD (Voverriding_terminal_local_map) = val;
}
static inline void
kset_real_last_command (struct kboard *kb, Lisp_Object val)
{
  kb->INTERNAL_FIELD (Vreal_last_command) = val;
}
static inline void
kset_system_key_syms (struct kboard *kb, Lisp_Object val)
{
  kb->INTERNAL_FIELD (system_key_syms) = val;
}

500

501
/* Add C to the echo string, if echoing is going on.
Jim Blandy's avatar
Jim Blandy committed
502 503 504
   C can be a character, which is printed prettily ("M-C-x" and all that
   jazz), or a symbol, whose name is printed.  */

505
static void
506
echo_char (Lisp_Object c)
Jim Blandy's avatar
Jim Blandy committed
507
{
508
  if (current_kboard->immediate_echo)
Jim Blandy's avatar
Jim Blandy committed
509
    {
510
      int size = KEY_DESCRIPTION_SIZE + 100;
511
      char *buffer = alloca (size);
512 513
      char *ptr = buffer;
      Lisp_Object echo_string;
Jim Blandy's avatar
Jim Blandy committed
514

515
      echo_string = KVAR (current_kboard, echo_string);
Juanma Barranquero's avatar
Juanma Barranquero committed
516

Jim Blandy's avatar
Jim Blandy committed
517
      /* If someone has passed us a composite event, use its head symbol.  */
518
      c = EVENT_HEAD (c);
Jim Blandy's avatar
Jim Blandy committed
519

520
      if (INTEGERP (c))
Jim Blandy's avatar
Jim Blandy committed
521
	{
522
	  ptr = push_key_description (XINT (c), ptr, 1);
Jim Blandy's avatar
Jim Blandy committed
523
	}
524
      else if (SYMBOLP (c))
Jim Blandy's avatar
Jim Blandy committed
525
	{
526 527
	  Lisp_Object name = SYMBOL_NAME (c);
	  int nbytes = SBYTES (name);
Juanma Barranquero's avatar
Juanma Barranquero committed
528

529
	  if (size - (ptr - buffer) < nbytes)
530 531
	    {
	      int offset = ptr - buffer;
532
	      size = max (2 * size, size + nbytes);
533
	      buffer = alloca (size);
534 535 536
	      ptr = buffer + offset;
	    }

537
	  ptr += copy_text (SDATA (name), (unsigned char *) ptr, nbytes,
538
			    STRING_MULTIBYTE (name), 1);
Jim Blandy's avatar
Jim Blandy committed
539 540
	}

541
      if ((NILP (echo_string) || SCHARS (echo_string) == 0)
Karl Heuer's avatar
Karl Heuer committed
542
	  && help_char_p (c))
Jim Blandy's avatar
Jim Blandy committed
543
	{
544 545
	  const char *text = " (Type ? for further options)";
	  int len = strlen (text);
Juanma Barranquero's avatar
Juanma Barranquero committed
546

547 548 549 550
	  if (size - (ptr - buffer) < len)
	    {
	      int offset = ptr - buffer;
	      size += len;
551
	      buffer = alloca (size);
552 553 554
	      ptr = buffer + offset;
	    }

555
	  memcpy (ptr, text, len);
556
	  ptr += len;
Jim Blandy's avatar
Jim Blandy committed
557 558
	}

559 560
      /* Replace a dash from echo_dash with a space, otherwise
	 add a space at the end as a separator between keys.  */
561
      if (STRINGP (echo_string)
562
	  && SCHARS (echo_string) > 1)
563
	{
564 565 566 567
	  Lisp_Object last_char, prev_char, idx;

	  idx = make_number (SCHARS (echo_string) - 2);
	  prev_char = Faref (echo_string, idx);
568 569 570 571

	  idx = make_number (SCHARS (echo_string) - 1);
	  last_char = Faref (echo_string, idx);

572 573 574
	  /* We test PREV_CHAR to make sure this isn't the echoing
	     of a minus-sign.  */
	  if (XINT (last_char) == '-' && XINT (prev_char) != ' ')
575 576 577 578
	    Faset (echo_string, idx, make_number (' '));
	  else
	    echo_string = concat2 (echo_string, build_string (" "));
	}
579 580
      else if (STRINGP (echo_string))
	echo_string = concat2 (echo_string, build_string (" "));
581

Paul Eggert's avatar
Paul Eggert committed
582 583 584
      kset_echo_string
	(current_kboard,
	 concat2 (echo_string, make_string (buffer, ptr - buffer)));
Jim Blandy's avatar
Jim Blandy committed
585

586
      echo_now ();
Jim Blandy's avatar
Jim Blandy committed
587 588 589 590 591 592
    }
}

/* Temporarily add a dash to the end of the echo string if it's not
   empty, so that it serves as a mini-prompt for the very next character.  */

593
static void
594
echo_dash (void)
Jim Blandy's avatar
Jim Blandy committed
595
{
596
  /* Do nothing if not echoing at all.  */
597
  if (NILP (KVAR (current_kboard, echo_string)))
598 599
    return;

600 601 602
  if (this_command_key_count == 0)
    return;

603
  if (!current_kboard->immediate_echo
604
      && SCHARS (KVAR (current_kboard, echo_string)) == 0)
Jim Blandy's avatar
Jim Blandy committed
605
    return;
Juanma Barranquero's avatar
Juanma Barranquero committed
606

607
  /* Do nothing if we just printed a prompt.  */
608
  if (current_kboard->echo_after_prompt
609
      == SCHARS (KVAR (current_kboard, echo_string)))
610
    return;
Juanma Barranquero's avatar
Juanma Barranquero committed
611

612
  /* Do nothing if we have already put a dash at the end.  */
613
  if (SCHARS (KVAR (current_kboard, echo_string)) > 1)
614
    {
615
      Lisp_Object last_char, prev_char, idx;
616

617 618
      idx = make_number (SCHARS (KVAR (current_kboard, echo_string)) - 2);
      prev_char = Faref (KVAR (current_kboard, echo_string), idx);
619

620 621
      idx = make_number (SCHARS (KVAR (current_kboard, echo_string)) - 1);
      last_char = Faref (KVAR (current_kboard, echo_string), idx);
622

623 624
      if (XINT (last_char) == '-' && XINT (prev_char) != ' ')
	return;
625 626
    }

Jim Blandy's avatar
Jim Blandy committed
627 628
  /* Put a dash at the end of the buffer temporarily,
     but make it go away when the next character is added.  */
Paul Eggert's avatar
Paul Eggert committed
629 630 631
  kset_echo_string
    (current_kboard,
     concat2 (KVAR (current_kboard, echo_string), build_string ("-")));
632
  echo_now ();
Jim Blandy's avatar
Jim Blandy committed
633 634 635 636 637
}

/* Display the current echo string, and begin echoing if not already
   doing so.  */

638
static void
639
echo_now (void)
Jim Blandy's avatar
Jim Blandy committed
640
{
641
  if (!current_kboard->immediate_echo)
Jim Blandy's avatar
Jim Blandy committed
642
    {
643
      ptrdiff_t i;
644
      current_kboard->immediate_echo = 1;
Jim Blandy's avatar
Jim Blandy committed
645 646

      for (i = 0; i < this_command_key_count; i++)
647 648
	{
	  Lisp_Object c;
649 650 651 652 653 654 655

	  /* Set before_command_echo_length to the value that would
	     have been saved before the start of this subcommand in
	     command_loop_1, if we had already been echoing then.  */
	  if (i == this_single_command_key_start)
	    before_command_echo_length = echo_length ();

656
	  c = AREF (this_command_keys, i);
657 658 659 660
	  if (! (EVENT_HAS_PARAMETERS (c)
		 && EQ (EVENT_HEAD_KIND (EVENT_HEAD (c)), Qmouse_movement)))
	    echo_char (c);
	}
661 662 663 664 665 666 667 668

      /* Set before_command_echo_length to the value that would
	 have been saved before the start of this subcommand in
	 command_loop_1, if we had already been echoing then.  */
      if (this_command_key_count == this_single_command_key_start)
	before_command_echo_length = echo_length ();

      /* Put a dash at the end to invite the user to type more.  */
Jim Blandy's avatar
Jim Blandy committed
669 670 671 672
      echo_dash ();
    }

  echoing = 1;
673 674 675
  message3_nolog (KVAR (current_kboard, echo_string),
		  SBYTES (KVAR (current_kboard, echo_string)),
		  STRING_MULTIBYTE (KVAR (current_kboard, echo_string)));
Jim Blandy's avatar
Jim Blandy committed
676 677
  echoing = 0;

678 679 680 681
  /* Record in what buffer we echoed, and from which kboard.  */
  echo_message_buffer = echo_area_buffer[0];
  echo_kboard = current_kboard;

Jim Blandy's avatar
Jim Blandy committed
682
  if (waiting_for_input && !NILP (Vquit_flag))
683
    quit_throw_to_read_char (0);
Jim Blandy's avatar
Jim Blandy committed
684 685 686 687
}

/* Turn off echoing, for the start of a new command.  */

Andreas Schwab's avatar
Andreas Schwab committed
688
void
689
cancel_echoing (void)
Jim Blandy's avatar
Jim Blandy committed
690
{
691 692
  current_kboard->immediate_echo = 0;
  current_kboard->echo_after_prompt = -1;
Paul Eggert's avatar
Paul Eggert committed
693
  kset_echo_string (current_kboard, Qnil);
694 695 696
  ok_to_echo_at_next_pause = NULL;
  echo_kboard = NULL;
  echo_message_buffer = Qnil;
Jim Blandy's avatar
Jim Blandy committed
697 698 699 700
}

/* Return the length of the current echo string.  */

701
static ptrdiff_t
702
echo_length (void)
Jim Blandy's avatar
Jim Blandy committed
703
{
704 705
  return (STRINGP (KVAR (current_kboard, echo_string))
	  ? SCHARS (KVAR (current_kboard, echo_string))
706
	  : 0);
Jim Blandy's avatar
Jim Blandy committed
707 708 709 710
}

/* Truncate the current echo message to its first LEN chars.
   This and echo_char get used by read_key_sequence when the user
Jim Blandy's avatar
Jim Blandy committed
711
   switches frames while entering a key sequence.  */
Jim Blandy's avatar
Jim Blandy committed
712 713

static void
714
echo_truncate (ptrdiff_t nchars)
715
{
716
  if (STRINGP (KVAR (current_kboard, echo_string)))
Paul Eggert's avatar
Paul Eggert committed
717 718 719
    kset_echo_string (current_kboard,
		      Fsubstring (KVAR (current_kboard, echo_string),
				  make_number (0), make_number (nchars)));
720
  truncate_echo_area (nchars);
Jim Blandy's avatar
Jim Blandy committed
721 722 723 724 725
}


/* Functions for manipulating this_command_keys.  */
static void
726
add_command_key (Lisp_Object key)
Jim Blandy's avatar
Jim Blandy committed
727
{
728 729
#if 0 /* Not needed after we made Freset_this_command_lengths
	 do the job immediately.  */
730 731 732 733 734
  /* If reset-this-command-length was called recently, obey it now.
     See the doc string of that function for an explanation of why.  */
  if (before_command_restore_flag)
    {
      this_command_key_count = before_command_key_count_1;
735 736
      if (this_command_key_count < this_single_command_key_start)
	this_single_command_key_start = this_command_key_count;
737 738 739
      echo_truncate (before_command_echo_length_1);
      before_command_restore_flag = 0;
    }
740
#endif
741

742
  if (this_command_key_count >= ASIZE (this_command_keys))
743
    this_command_keys = larger_vector (this_command_keys, 1, -1);
744

745
  ASET (this_command_keys, this_command_key_count, key);
746
  ++this_command_key_count;
Jim Blandy's avatar
Jim Blandy committed
747
}
748

Jim Blandy's avatar
Jim Blandy committed
749 750

Lisp_Object
751
recursive_edit_1 (void)
Jim Blandy's avatar
Jim Blandy committed
752
{
753
  ptrdiff_t count = SPECPDL_INDEX ();
Jim Blandy's avatar
Jim Blandy committed
754 755 756 757 758 759 760 761
  Lisp_Object val;

  if (command_loop_level > 0)
    {
      specbind (Qstandard_output, Qt);
      specbind (Qstandard_input, Qt);
    }

762
#ifdef HAVE_WINDOW_SYSTEM
763
  /* The command loop has started an hourglass timer, so we have to
764
     cancel it here, otherwise it will fire because the recursive edit
765 766
     can take some time.  Do not check for display_hourglass_p here,
     because it could already be nil.  */
767
    cancel_hourglass ();
768 769
#endif

770 771 772 773 774 775 776 777 778 779 780 781
  /* This function may have been called from a debugger called from
     within redisplay, for instance by Edebugging a function called
     from fontification-functions.  We want to allow redisplay in
     the debugging session.

     The recursive edit is left with a `(throw exit ...)'.  The `exit'
     tag is not caught anywhere in redisplay, i.e. when we leave the
     recursive edit, the original redisplay leading to the recursive
     edit will be unwound.  The outcome should therefore be safe.  */
  specbind (Qinhibit_redisplay, Qnil);
  redisplaying_p = 0;

Jim Blandy's avatar
Jim Blandy committed
782 783 784
  val = command_loop ();
  if (EQ (val, Qt))
    Fsignal (Qquit, Qnil);
785 786 787
  /* Handle throw from read_minibuf when using minibuffer
     while it's active but we're in another window.  */
  if (STRINGP (val))
788
    xsignal1 (Qerror, val);
Jim Blandy's avatar
Jim Blandy committed
789

790
  return unbind_to (count, Qnil);
Jim Blandy's avatar
Jim Blandy committed
791 792 793
}

/* When an auto-save happens, record the "time", and don't do again soon.  */
794

795
void
796
record_auto_save (void)
Jim Blandy's avatar
Jim Blandy committed
797
{
798
  last_auto_save = num_nonmacro_input_events;
Jim Blandy's avatar
Jim Blandy committed
799
}
800 801 802

/* Make an auto save happen as soon as possible at command level.  */

803
#ifdef SIGDANGER
Andreas Schwab's avatar
Andreas Schwab committed
804
void
805
force_auto_save_soon (void)
806 807
{
  last_auto_save = - auto_save_interval - 1;
808 809

  record_asynch_buffer_change ();
810
}
811
#endif
Jim Blandy's avatar
Jim Blandy committed
812

Paul Eggert's avatar
Paul Eggert committed
813
DEFUN ("recursive-edit", Frecursive_edit, Srecursive_edit, 0, 0, "",
814 815 816
       doc: /* Invoke the editor command loop recursively.
To get out of the recursive edit, a command can do `(throw 'exit nil)';
that tells this function to return.
817
Alternatively, `(throw 'exit t)' makes this function signal an error.
818
This function is called by the editor initialization to begin editing.  */)
Dan Nicolaescu's avatar
Dan Nicolaescu committed
819
  (void)
Jim Blandy's avatar
Jim Blandy committed
820
{
821
  ptrdiff_t count = SPECPDL_INDEX ();
822
  Lisp_Object buffer;
Jim Blandy's avatar
Jim Blandy committed
823

824 825 826 827 828
  /* If we enter while input is blocked, don't lock up here.
     This may happen through the debugger during redisplay.  */
  if (INPUT_BLOCKED_P)
    return Qnil;

Jim Blandy's avatar
Jim Blandy committed
829 830 831
  command_loop_level++;
  update_mode_lines = 1;

832
  if (command_loop_level
833
      && current_buffer != XBUFFER (XWINDOW (selected_window)->buffer))
834 835 836 837 838 839 840 841
    buffer = Fcurrent_buffer ();
  else
    buffer = Qnil;

  /* If we leave recursive_edit_1 below with a `throw' for instance,
     like it is done in the splash screen display, we have to
     make sure that we restore single_kboard as command_loop_1
     would have done if it were left normally.  */
842 843
  if (command_loop_level > 0)
    temporarily_switch_to_single_kboard (SELECTED_FRAME ());
844
  record_unwind_protect (recursive_edit_unwind, buffer);
845

Jim Blandy's avatar
Jim Blandy committed
846 847 848 849 850
  recursive_edit_1 ();
  return unbind_to (count, Qnil);
}

Lisp_Object
851
recursive_edit_unwind (Lisp_Object buffer)
Jim Blandy's avatar
Jim Blandy committed
852
{
853 854
  if (BUFFERP (buffer))
    Fset_buffer (buffer);
Juanma Barranquero's avatar
Juanma Barranquero committed
855

Jim Blandy's avatar
Jim Blandy committed
856 857 858 859
  command_loop_level--;
  update_mode_lines = 1;
  return Qnil;
}
860

Jim Blandy's avatar
Jim Blandy committed
861

862
#if 0  /* These two functions are now replaced with
863
          temporarily_switch_to_single_kboard.  */
Karl Heuer's avatar
Karl Heuer committed
864
static void
865
any_kboard_state ()
Karl Heuer's avatar
Karl Heuer committed
866
{
867 868 869 870
#if 0 /* Theory: if there's anything in Vunread_command_events,
	 it will right away be read by read_key_sequence,
	 and then if we do switch KBOARDS, it will go into the side
	 queue then.  So we don't need to do anything special here -- rms.  */
Karl Heuer's avatar
Karl Heuer committed
871
  if (CONSP (Vunread_command_events))
872
    {
873 874 875
      current_kboard->kbd_queue
	= nconc2 (Vunread_command_events, current_kboard->kbd_queue);
      current_kboard->kbd_queue_has_data = 1;
876
    }
Karl Heuer's avatar
Karl Heuer committed
877
  Vunread_command_events = Qnil;
878 879
#endif
  single_kboard = 0;
Karl Heuer's avatar
Karl Heuer committed
880
}
881 882 883 884 885 886 887 888 889

/* Switch to the single-kboard state, making current_kboard
   the only KBOARD from which further input is accepted.  */

void
single_kboard_state ()
{
  single_kboard = 1;
}
890
#endif
891

892 893 894 895
/* If we're in single_kboard state for kboard KBOARD,
   get out of it.  */

void