keyboard.c 369 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, 1999-2011  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>
21
#include <signal.h>
Jim Blandy's avatar
Jim Blandy committed
22
#include <stdio.h>
23
#include <setjmp.h>
24
#include "lisp.h"
Jim Blandy's avatar
Jim Blandy committed
25 26
#include "termchar.h"
#include "termopts.h"
27
#include "frame.h"
Jim Blandy's avatar
Jim Blandy committed
28 29
#include "termhooks.h"
#include "macros.h"
30
#include "keyboard.h"
Jim Blandy's avatar
Jim Blandy committed
31 32 33
#include "window.h"
#include "commands.h"
#include "buffer.h"
34
#include "character.h"
Jim Blandy's avatar
Jim Blandy committed
35
#include "disptab.h"
36
#include "dispextern.h"
Richard M. Stallman's avatar
Richard M. Stallman committed
37
#include "syntax.h"
Richard M. Stallman's avatar
Richard M. Stallman committed
38
#include "intervals.h"
Stefan Monnier's avatar
Stefan Monnier committed
39
#include "keymap.h"
40
#include "blockinput.h"
41
#include "puresize.h"
42 43
#include "systime.h"
#include "atimer.h"
44
#include "process.h"
Jim Blandy's avatar
Jim Blandy committed
45 46
#include <errno.h>

47 48 49
#ifdef HAVE_GTK_AND_PTHREAD
#include <pthread.h>
#endif
50 51 52 53
#ifdef MSDOS
#include "msdos.h"
#include <time.h>
#else /* not MSDOS */
Jim Blandy's avatar
Jim Blandy committed
54
#include <sys/ioctl.h>
55
#endif /* not MSDOS */
Jim Blandy's avatar
Jim Blandy committed
56

Jim Blandy's avatar
Jim Blandy committed
57 58
#include "syssignal.h"

59 60
#include <sys/types.h>
#include <unistd.h>
61 62
#include <fcntl.h>

63 64 65 66 67
/* This is to get the definitions of the XK_ symbols.  */
#ifdef HAVE_X_WINDOWS
#include "xterm.h"
#endif

68 69 70 71
#ifdef HAVE_NTGUI
#include "w32term.h"
#endif /* HAVE_NTGUI */

72 73 74 75
#ifdef HAVE_NS
#include "nsterm.h"
#endif

76 77 78
/* Variables for blockinput.h: */

/* Non-zero if interrupt input is blocked right now.  */
79
volatile int interrupt_input_blocked;
80 81 82

/* Nonzero means an input interrupt has arrived
   during the current critical section.  */
83
int interrupt_input_pending;
84

Chong Yidong's avatar
Chong Yidong committed
85 86 87 88 89
/* 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.  */
90
#ifdef SYNC_INPUT
Chong Yidong's avatar
Chong Yidong committed
91
int pending_signals;
92
#endif
Chong Yidong's avatar
Chong Yidong committed
93

94
#define KBD_BUFFER_SIZE 4096
Jim Blandy's avatar
Jim Blandy committed
95

96 97 98
KBOARD *initial_kboard;
KBOARD *current_kboard;
KBOARD *all_kboards;
99
int single_kboard;
100

Jim Blandy's avatar
Jim Blandy committed
101
/* Non-nil disable property on a command means
102 103
   do not execute it; call disabled-command-function's value instead.  */
Lisp_Object Qdisabled, Qdisabled_command_function;
Jim Blandy's avatar
Jim Blandy committed
104

105
#define NUM_RECENT_KEYS (300)
Jim Blandy's avatar
Jim Blandy committed
106 107
int recent_keys_index;	/* Index for storing next element into recent_keys */
int total_keys;		/* Total number of elements stored into recent_keys */
108
Lisp_Object recent_keys; /* Vector holds the last NUM_RECENT_KEYS keystrokes */
Jim Blandy's avatar
Jim Blandy committed
109

110 111 112 113 114 115 116
/* 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;
int this_command_key_count;
Jim Blandy's avatar
Jim Blandy committed
117

118 119 120 121
/* 1 after calling Freset_this_command_lengths.
   Usually it is 0.  */
int this_command_key_count_reset;

122 123 124 125 126 127
/* This vector is used as a buffer to record the events that were actually read
   by read_key_sequence.  */
Lisp_Object raw_keybuf;
int raw_keybuf_count;

#define GROW_RAW_KEYBUF							\
128
 if (raw_keybuf_count == XVECTOR (raw_keybuf)->size)			\
129
   raw_keybuf = larger_vector (raw_keybuf, raw_keybuf_count * 2, Qnil)  \
130

131 132 133 134
/* Number of elements of this_command_keys
   that precede this key sequence.  */
int this_single_command_key_start;

135 136 137 138 139
/* Record values of this_command_key_count and echo_length ()
   before this command was read.  */
static int before_command_key_count;
static int before_command_echo_length;

Jim Blandy's avatar
Jim Blandy committed
140
/* For longjmp to where kbd input is being done.  */
141

Jim Blandy's avatar
Jim Blandy committed
142 143 144 145 146 147
static jmp_buf getcjmp;

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

/* True while displaying for echoing.   Delays C-g throwing.  */
148

149
int echoing;
Jim Blandy's avatar
Jim Blandy committed
150

151 152 153 154 155
/* 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;

156 157 158 159
/* 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.  */
160

161
struct kboard *echo_kboard;
162

163 164 165
/* The buffer used for echoing.  Set in echo_now, reset in
   cancel_echoing.  */

166
Lisp_Object echo_message_buffer;
167

168
/* Nonzero means C-g should cause immediate error-signal.  */
Jim Blandy's avatar
Jim Blandy committed
169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191
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.  */
int command_loop_level;

192 193
/* 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
194
   next command input, after any unread_command_events.
195 196 197 198 199

   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;
200

Jim Blandy's avatar
Jim Blandy committed
201
/* Last size recorded for a current buffer which is not a minibuffer.  */
202
static EMACS_INT last_non_minibuf_size;
Jim Blandy's avatar
Jim Blandy committed
203

204 205
/* Total number of times read_char has returned, modulo SIZE_MAX + 1.  */
size_t num_input_events;
Jim Blandy's avatar
Jim Blandy committed
206

207
/* Value of num_nonmacro_input_events as of last auto save.  */
Jim Blandy's avatar
Jim Blandy committed
208 209 210

int last_auto_save;

211 212
/* This is like Vthis_command, except that commands never set it.  */
Lisp_Object real_this_command;
Jim Blandy's avatar
Jim Blandy committed
213

214
/* The value of point when the last command was started.  */
215
EMACS_INT last_point_position;
216

217 218 219
/* The buffer that was current when the last command was started.  */
Lisp_Object last_point_position_buffer;

220 221 222
/* The window that was selected when the last command was started.  */
Lisp_Object last_point_position_window;

223 224 225 226 227 228 229
/* 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
230 231
/* The timestamp of the last input event we received from the X server.
   X Windows wants this for selection ownership.  */
Jim Blandy's avatar
Jim Blandy committed
232 233
unsigned long last_event_timestamp;

234
Lisp_Object Qx_set_selection, QPRIMARY, Qhandle_switch_frame;
235

Jim Blandy's avatar
Jim Blandy committed
236 237 238
Lisp_Object Qself_insert_command;
Lisp_Object Qforward_char;
Lisp_Object Qbackward_char;
239
Lisp_Object Qundefined;
240
Lisp_Object Qtimer_event_handler;
Jim Blandy's avatar
Jim Blandy committed
241 242 243 244 245

/* read_key_sequence stores here the command definition of the
   key sequence that it reads.  */
Lisp_Object read_key_sequence_cmd;

246 247
Lisp_Object Qinput_method_function;

Stefan Monnier's avatar
Stefan Monnier committed
248
Lisp_Object Qdeactivate_mark;
249

250 251
Lisp_Object Qrecompute_lucid_menubar, Qactivate_menubar_hook;

252
Lisp_Object Qecho_area_clear_hook;
253

254
/* Hooks to run before and after each command.  */
255 256
Lisp_Object Qpre_command_hook;
Lisp_Object Qpost_command_hook;
257

258
Lisp_Object Qdeferred_action_function;
259

260 261 262
Lisp_Object Qinput_method_exit_on_first_char;
Lisp_Object Qinput_method_use_echo_area;

263 264
Lisp_Object Qhelp_form_show;

Jim Blandy's avatar
Jim Blandy committed
265 266 267 268 269 270
/* File in which we write all commands we read.  */
FILE *dribble;

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

271
/* Circular buffer for pre-read keyboard input.  */
272

273 274 275 276
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.
277
   This may be kbd_buffer + KBD_BUFFER_SIZE, meaning that the
278 279 280 281 282 283
   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].  */
284
static struct input_event * volatile kbd_store_ptr;
285 286 287 288

/* 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
289
   there is input available if the two pointers are not equal.
290 291 292 293 294

   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
295 296
/* Symbols to head events.  */
Lisp_Object Qmouse_movement;
297
Lisp_Object Qscroll_bar_movement;
298
Lisp_Object Qswitch_frame;
299
Lisp_Object Qdelete_frame;
300 301
Lisp_Object Qiconify_frame;
Lisp_Object Qmake_frame_visible;
Pavel Janík's avatar
Pavel Janík committed
302
Lisp_Object Qselect_window;
303
Lisp_Object Qhelp_echo;
304

Nick Roberts's avatar
Nick Roberts committed
305
#if defined (HAVE_MOUSE) || defined (HAVE_GPM)
306 307 308
Lisp_Object Qmouse_fixup_help_message;
#endif

Jim Blandy's avatar
Jim Blandy committed
309 310 311
/* Symbols to denote kinds of events.  */
Lisp_Object Qfunction_key;
Lisp_Object Qmouse_click;
312
#if defined (WINDOWSNT)
313
Lisp_Object Qlanguage_change;
314
#endif
315
Lisp_Object Qdrag_n_drop;
316
Lisp_Object Qsave_session;
317 318 319
#ifdef HAVE_DBUS
Lisp_Object Qdbus_event;
#endif
320 321
Lisp_Object Qconfig_changed_event;

Jim Blandy's avatar
Jim Blandy committed
322 323 324 325
/* Lisp_Object Qmouse_movement; - also an event header */

/* Properties of event headers.  */
Lisp_Object Qevent_kind;
326
Lisp_Object Qevent_symbol_elements;
Jim Blandy's avatar
Jim Blandy committed
327

328
/* menu and tool bar item parts */
329
Lisp_Object Qmenu_enable;
330
Lisp_Object QCenable, QCvisible, QChelp, QCfilter, QCkeys, QCkey_sequence;
331
Lisp_Object QCbutton, QCtoggle, QCradio, QClabel, QCvert_only;
332

333 334 335 336 337 338 339 340 341 342 343 344 345
/* 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.  */
Lisp_Object Qmodifier_cache;

346
/* Symbols to use for parts of windows.  */
Jim Blandy's avatar
Jim Blandy committed
347
Lisp_Object Qmode_line;
Jim Blandy's avatar
Jim Blandy committed
348
Lisp_Object Qvertical_line;
349
Lisp_Object Qvertical_scroll_bar;
350 351
Lisp_Object Qmenu_bar;

352
Lisp_Object recursive_edit_unwind (Lisp_Object buffer), command_loop (void);
353
Lisp_Object Qextended_command_history;
354
EMACS_TIME timer_check (void);
Jim Blandy's avatar
Jim Blandy committed
355

356 357
static void record_menu_key (Lisp_Object c);
static int echo_length (void);
358

359 360
Lisp_Object Qpolling_period;

361 362 363
/* Incremented whenever a timer is run.  */
int timers_run;

Jim Blandy's avatar
Jim Blandy committed
364 365 366
/* 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
367 368 369 370 371 372 373 374 375 376 377 378 379 380 381

/* 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;

/* Allow m- file to inhibit use of FIONREAD.  */
#ifdef BROKEN_FIONREAD
#undef FIONREAD
#endif

/* We are unable to use interrupts if FIONREAD is not available,
   so flush SIGIO so we won't try.  */
Steven Tamm's avatar
Steven Tamm committed
382
#if !defined (FIONREAD)
Jim Blandy's avatar
Jim Blandy committed
383 384 385 386 387
#ifdef SIGIO
#undef SIGIO
#endif
#endif

388
/* If we support a window system, turn on the code to poll periodically
389
   to detect C-g.  It isn't actually used when doing interrupt input.  */
Andrew Choi's avatar
In src:  
Andrew Choi committed
390
#if defined(HAVE_WINDOW_SYSTEM) && !defined(USE_ASYNC_EVENTS)
Jim Blandy's avatar
Jim Blandy committed
391 392
#define POLL_FOR_INPUT
#endif
393

394 395 396 397
/* The time when Emacs started being idle.  */

static EMACS_TIME timer_idleness_start_time;

398 399 400 401 402
/* 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
403 404 405

/* Global variable declarations.  */

406 407 408 409 410
/* 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
411
/* Function for init_keyboard to call with no args (if nonzero).  */
412
void (*keyboard_init_hook) (void);
Jim Blandy's avatar
Jim Blandy committed
413

414 415 416 417 418 419 420 421
static int read_avail_input (int);
static void get_input_pending (int *, int);
static int readable_events (int);
static Lisp_Object read_char_x_menu_prompt (int, Lisp_Object *,
                                            Lisp_Object, int *);
static Lisp_Object read_char_minibuf_menu_prompt (int, int,
                                                  Lisp_Object *);
static Lisp_Object make_lispy_event (struct input_event *);
Nick Roberts's avatar
Nick Roberts committed
422
#if defined (HAVE_MOUSE) || defined (HAVE_GPM)
423 424 425 426
static Lisp_Object make_lispy_movement (struct frame *, Lisp_Object,
                                        enum scroll_bar_part,
                                        Lisp_Object, Lisp_Object,
                                        unsigned long);
427
#endif
428
static Lisp_Object modify_event_symbol (EMACS_INT, unsigned, Lisp_Object,
429
                                        Lisp_Object, const char *const *,
430 431 432 433 434 435 436
                                        Lisp_Object *, unsigned);
static Lisp_Object make_lispy_switch_frame (Lisp_Object);
static void save_getcjmp (jmp_buf);
static void restore_getcjmp (jmp_buf);
static Lisp_Object apply_modifiers (int, Lisp_Object);
static void clear_event (struct input_event *);
static Lisp_Object restore_kboard_configuration (Lisp_Object);
437
static void interrupt_signal (int signalnum);
438
#ifdef SIGIO
439
static void input_available_signal (int signo);
440
#endif
441
INFUN (Fcommand_execute, 4);
442 443 444 445
static void handle_interrupt (void);
static void timer_start_idle (void);
static void timer_stop_idle (void);
static void timer_resume_idle (void);
446
static void handle_user_signal (int);
447 448
static char *find_user_signal_name (int);
static int store_user_signal_events (void);
Jim Blandy's avatar
Jim Blandy committed
449

450

451
/* Add C to the echo string, if echoing is going on.
Jim Blandy's avatar
Jim Blandy committed
452 453 454
   C can be a character, which is printed prettily ("M-C-x" and all that
   jazz), or a symbol, whose name is printed.  */

455
static void
456
echo_char (Lisp_Object c)
Jim Blandy's avatar
Jim Blandy committed
457
{
458
  if (current_kboard->immediate_echo)
Jim Blandy's avatar
Jim Blandy committed
459
    {
460 461 462 463
      int size = KEY_DESCRIPTION_SIZE + 100;
      char *buffer = (char *) alloca (size);
      char *ptr = buffer;
      Lisp_Object echo_string;
Jim Blandy's avatar
Jim Blandy committed
464

465
      echo_string = KVAR (current_kboard, echo_string);
Juanma Barranquero's avatar
Juanma Barranquero committed
466

Jim Blandy's avatar
Jim Blandy committed
467
      /* If someone has passed us a composite event, use its head symbol.  */
468
      c = EVENT_HEAD (c);
Jim Blandy's avatar
Jim Blandy committed
469

470
      if (INTEGERP (c))
Jim Blandy's avatar
Jim Blandy committed
471
	{
472
	  ptr = push_key_description (XINT (c), ptr, 1);
Jim Blandy's avatar
Jim Blandy committed
473
	}
474
      else if (SYMBOLP (c))
Jim Blandy's avatar
Jim Blandy committed
475
	{
476 477
	  Lisp_Object name = SYMBOL_NAME (c);
	  int nbytes = SBYTES (name);
Juanma Barranquero's avatar
Juanma Barranquero committed
478

479
	  if (size - (ptr - buffer) < nbytes)
480 481
	    {
	      int offset = ptr - buffer;
482
	      size = max (2 * size, size + nbytes);
483 484 485 486
	      buffer = (char *) alloca (size);
	      ptr = buffer + offset;
	    }

487
	  ptr += copy_text (SDATA (name), (unsigned char *) ptr, nbytes,
488
			    STRING_MULTIBYTE (name), 1);
Jim Blandy's avatar
Jim Blandy committed
489 490
	}

491
      if ((NILP (echo_string) || SCHARS (echo_string) == 0)
Karl Heuer's avatar
Karl Heuer committed
492
	  && help_char_p (c))
Jim Blandy's avatar
Jim Blandy committed
493
	{
494 495
	  const char *text = " (Type ? for further options)";
	  int len = strlen (text);
Juanma Barranquero's avatar
Juanma Barranquero committed
496

497 498 499 500 501 502 503 504
	  if (size - (ptr - buffer) < len)
	    {
	      int offset = ptr - buffer;
	      size += len;
	      buffer = (char *) alloca (size);
	      ptr = buffer + offset;
	    }

505
	  memcpy (ptr, text, len);
506
	  ptr += len;
Jim Blandy's avatar
Jim Blandy committed
507 508
	}

509 510
      /* Replace a dash from echo_dash with a space, otherwise
	 add a space at the end as a separator between keys.  */
511
      if (STRINGP (echo_string)
512
	  && SCHARS (echo_string) > 1)
513
	{
514 515 516 517
	  Lisp_Object last_char, prev_char, idx;

	  idx = make_number (SCHARS (echo_string) - 2);
	  prev_char = Faref (echo_string, idx);
518 519 520 521

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

522 523 524
	  /* We test PREV_CHAR to make sure this isn't the echoing
	     of a minus-sign.  */
	  if (XINT (last_char) == '-' && XINT (prev_char) != ' ')
525 526 527 528
	    Faset (echo_string, idx, make_number (' '));
	  else
	    echo_string = concat2 (echo_string, build_string (" "));
	}
529 530
      else if (STRINGP (echo_string))
	echo_string = concat2 (echo_string, build_string (" "));
531

532
      KVAR (current_kboard, echo_string)
533
	= concat2 (echo_string, make_string (buffer, ptr - buffer));
Jim Blandy's avatar
Jim Blandy committed
534

535
      echo_now ();
Jim Blandy's avatar
Jim Blandy committed
536 537 538 539 540 541
    }
}

/* 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.  */

542
static void
543
echo_dash (void)
Jim Blandy's avatar
Jim Blandy committed
544
{
545
  /* Do nothing if not echoing at all.  */
546
  if (NILP (KVAR (current_kboard, echo_string)))
547 548
    return;

549 550 551
  if (this_command_key_count == 0)
    return;

552
  if (!current_kboard->immediate_echo
553
      && SCHARS (KVAR (current_kboard, echo_string)) == 0)
Jim Blandy's avatar
Jim Blandy committed
554
    return;
Juanma Barranquero's avatar
Juanma Barranquero committed
555

556
  /* Do nothing if we just printed a prompt.  */
557
  if (current_kboard->echo_after_prompt
558
      == SCHARS (KVAR (current_kboard, echo_string)))
559
    return;
Juanma Barranquero's avatar
Juanma Barranquero committed
560

561
  /* Do nothing if we have already put a dash at the end.  */
562
  if (SCHARS (KVAR (current_kboard, echo_string)) > 1)
563
    {
564
      Lisp_Object last_char, prev_char, idx;
565

566 567
      idx = make_number (SCHARS (KVAR (current_kboard, echo_string)) - 2);
      prev_char = Faref (KVAR (current_kboard, echo_string), idx);
568

569 570
      idx = make_number (SCHARS (KVAR (current_kboard, echo_string)) - 1);
      last_char = Faref (KVAR (current_kboard, echo_string), idx);
571

572 573
      if (XINT (last_char) == '-' && XINT (prev_char) != ' ')
	return;
574 575
    }

Jim Blandy's avatar
Jim Blandy committed
576 577
  /* Put a dash at the end of the buffer temporarily,
     but make it go away when the next character is added.  */
578
  KVAR (current_kboard, echo_string) = concat2 (KVAR (current_kboard, echo_string),
579
					 build_string ("-"));
580
  echo_now ();
Jim Blandy's avatar
Jim Blandy committed
581 582 583 584 585
}

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

586
void
587
echo_now (void)
Jim Blandy's avatar
Jim Blandy committed
588
{
589
  if (!current_kboard->immediate_echo)
Jim Blandy's avatar
Jim Blandy committed
590 591
    {
      int i;
592
      current_kboard->immediate_echo = 1;
Jim Blandy's avatar
Jim Blandy committed
593 594

      for (i = 0; i < this_command_key_count; i++)
595 596
	{
	  Lisp_Object c;
597 598 599 600 601 602 603

	  /* 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 ();

604 605 606 607 608
	  c = XVECTOR (this_command_keys)->contents[i];
	  if (! (EVENT_HAS_PARAMETERS (c)
		 && EQ (EVENT_HEAD_KIND (EVENT_HEAD (c)), Qmouse_movement)))
	    echo_char (c);
	}
609 610 611 612 613 614 615 616

      /* 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
617 618 619 620
      echo_dash ();
    }

  echoing = 1;
621 622 623
  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
624 625
  echoing = 0;

626 627 628 629
  /* 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
630 631 632 633 634 635
  if (waiting_for_input && !NILP (Vquit_flag))
    quit_throw_to_read_char ();
}

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

Andreas Schwab's avatar
Andreas Schwab committed
636
void
637
cancel_echoing (void)
Jim Blandy's avatar
Jim Blandy committed
638
{
639 640
  current_kboard->immediate_echo = 0;
  current_kboard->echo_after_prompt = -1;
641
  KVAR (current_kboard, echo_string) = Qnil;
642 643 644
  ok_to_echo_at_next_pause = NULL;
  echo_kboard = NULL;
  echo_message_buffer = Qnil;
Jim Blandy's avatar
Jim Blandy committed
645 646 647 648 649
}

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

static int
650
echo_length (void)
Jim Blandy's avatar
Jim Blandy committed
651
{
652 653
  return (STRINGP (KVAR (current_kboard, echo_string))
	  ? SCHARS (KVAR (current_kboard, echo_string))
654
	  : 0);
Jim Blandy's avatar
Jim Blandy committed
655 656 657 658
}

/* 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
659
   switches frames while entering a key sequence.  */
Jim Blandy's avatar
Jim Blandy committed
660 661

static void
662
echo_truncate (EMACS_INT nchars)
663
{
664 665 666
  if (STRINGP (KVAR (current_kboard, echo_string)))
    KVAR (current_kboard, echo_string)
      = Fsubstring (KVAR (current_kboard, echo_string),
667 668
		    make_number (0), make_number (nchars));
  truncate_echo_area (nchars);
Jim Blandy's avatar
Jim Blandy committed
669 670 671 672 673
}


/* Functions for manipulating this_command_keys.  */
static void
674
add_command_key (Lisp_Object key)
Jim Blandy's avatar
Jim Blandy committed
675
{
676 677
#if 0 /* Not needed after we made Freset_this_command_lengths
	 do the job immediately.  */
678 679 680 681 682
  /* 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;
683 684
      if (this_command_key_count < this_single_command_key_start)
	this_single_command_key_start = this_command_key_count;
685 686 687
      echo_truncate (before_command_echo_length_1);
      before_command_restore_flag = 0;
    }
688
#endif
689

690 691 692 693
  if (this_command_key_count >= ASIZE (this_command_keys))
    this_command_keys = larger_vector (this_command_keys,
				       2 * ASIZE (this_command_keys),
				       Qnil);
694

695
  ASET (this_command_keys, this_command_key_count, key);
696
  ++this_command_key_count;
Jim Blandy's avatar
Jim Blandy committed
697
}
698

Jim Blandy's avatar
Jim Blandy committed
699 700

Lisp_Object
701
recursive_edit_1 (void)
Jim Blandy's avatar
Jim Blandy committed
702
{
Juanma Barranquero's avatar
Juanma Barranquero committed
703
  int count = SPECPDL_INDEX ();
Jim Blandy's avatar
Jim Blandy committed
704 705 706 707 708 709 710 711
  Lisp_Object val;

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

712
#ifdef HAVE_WINDOW_SYSTEM
713
  /* The command loop has started an hourglass timer, so we have to
714
     cancel it here, otherwise it will fire because the recursive edit
715 716
     can take some time.  Do not check for display_hourglass_p here,
     because it could already be nil.  */
717
    cancel_hourglass ();
718 719
#endif

720 721 722 723 724 725 726 727 728 729 730 731
  /* 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
732 733 734
  val = command_loop ();
  if (EQ (val, Qt))
    Fsignal (Qquit, Qnil);
735 736 737
  /* Handle throw from read_minibuf when using minibuffer
     while it's active but we're in another window.  */
  if (STRINGP (val))
738
    xsignal1 (Qerror, val);
Jim Blandy's avatar
Jim Blandy committed
739

740
  return unbind_to (count, Qnil);
Jim Blandy's avatar
Jim Blandy committed
741 742 743
}

/* When an auto-save happens, record the "time", and don't do again soon.  */
744

745
void
746
record_auto_save (void)
Jim Blandy's avatar
Jim Blandy committed
747
{
748
  last_auto_save = num_nonmacro_input_events;
Jim Blandy's avatar
Jim Blandy committed
749
}
750 751 752

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

Andreas Schwab's avatar
Andreas Schwab committed
753
void
754
force_auto_save_soon (void)
755 756
{
  last_auto_save = - auto_save_interval - 1;
757 758

  record_asynch_buffer_change ();
759
}
Jim Blandy's avatar
Jim Blandy committed
760

761
DEFUE ("recursive-edit", Frecursive_edit, Srecursive_edit, 0, 0, "",
762 763 764
       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.
765
Alternatively, `(throw 'exit t)' makes this function signal an error.
766
This function is called by the editor initialization to begin editing.  */)
Dan Nicolaescu's avatar
Dan Nicolaescu committed
767
  (void)
Jim Blandy's avatar
Jim Blandy committed
768
{
Juanma Barranquero's avatar
Juanma Barranquero committed
769
  int count = SPECPDL_INDEX ();
770
  Lisp_Object buffer;
Jim Blandy's avatar
Jim Blandy committed
771

772 773 774 775 776
  /* 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
777 778 779
  command_loop_level++;
  update_mode_lines = 1;

780 781 782 783 784 785 786 787 788 789
  if (command_loop_level
      && current_buffer != XBUFFER (XWINDOW (selected_window)->buffer))
    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.  */
790 791
  if (command_loop_level > 0)
    temporarily_switch_to_single_kboard (SELECTED_FRAME ());
792
  record_unwind_protect (recursive_edit_unwind, buffer);
793

Jim Blandy's avatar
Jim Blandy committed
794 795 796 797 798
  recursive_edit_1 ();
  return unbind_to (count, Qnil);
}

Lisp_Object
799
recursive_edit_unwind (Lisp_Object buffer)
Jim Blandy's avatar
Jim Blandy committed
800
{
801 802
  if (BUFFERP (buffer))
    Fset_buffer (buffer);
Juanma Barranquero's avatar
Juanma Barranquero committed
803

Jim Blandy's avatar
Jim Blandy committed
804 805 806 807
  command_loop_level--;
  update_mode_lines = 1;
  return Qnil;
}
808

Jim Blandy's avatar
Jim Blandy committed
809

810 811
#if 0  /* These two functions are now replaced with
          temporarily_switch_to_single_kboard. */
Karl Heuer's avatar
Karl Heuer committed
812
static void
813
any_kboard_state ()
Karl Heuer's avatar
Karl Heuer committed
814
{
815 816 817 818
#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
819
  if (CONSP (Vunread_command_events))
820
    {
821 822 823
      current_kboard->kbd_queue
	= nconc2 (Vunread_command_events, current_kboard->kbd_queue);
      current_kboard->kbd_queue_has_data = 1;
824
    }
Karl Heuer's avatar
Karl Heuer committed
825
  Vunread_command_events = Qnil;
826 827
#endif
  single_kboard = 0;
Karl Heuer's avatar
Karl Heuer committed
828
}
829 830 831 832 833 834 835 836 837

/* 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;
}
838
#endif
839

840 841 842 843
/* If we're in single_kboard state for kboard KBOARD,
   get out of it.  */

void
844
not_single_kboard_state (KBOARD *kboard)
845 846 847 848 849
{
  if (kboard == current_kboard)
    single_kboard = 0;
}

850 851 852 853 854 855 856 857 858 859 860 861 862
/* Maintain a stack of kboards, so other parts of Emacs
   can switch temporarily to the kboard of a given frame
   and then revert to the previous status.  */

struct kboard_stack
{
  KBOARD *kboard;
  struct kboard_stack *next;
};

static struct kboard_stack *kboard_stack;

void
863
push_kboard (struct kboard *k)
864 865 866 867 868 869 870 871
{
  struct kboard_stack *p
    = (struct kboard_stack *) xmalloc (sizeof (struct kboard_stack));

  p->next = kboard_stack;
  p->kboard = current_kboard;
  kboard_stack = p;

872
  current_kboard = k;
873 874 875
}

void
876
pop_kboard (void)
877
{
878
  struct terminal *t;
879
  struct kboard_stack *p = kboard_stack;
880
  int found = 0;
881
  for (t = terminal_list; t; t = t->next_terminal)
882
    {
883
      if (t->kboard == p->kboard)
884 885
        {
          current_kboard = p->kboard;
886
          found = 1;
887 888 889
          break;
        }
    }
890
  if (!found)
891
    {
892
      /* The terminal we remembered has been deleted.  */
893
      current_kboard = FRAME_KBOARD (SELECTED_FRAME ());
894
      single_kboard = 0;
895
    }
896 897 898
  kboard_stack = p->next;
  xfree (p);
}
899

900 901 902 903 904 905 906 907 908
/* Switch to single_kboard mode, making current_kboard the only KBOARD
  from which further input is accepted.  If F is non-nil, set its
  KBOARD as the current keyboard.

  This function uses record_unwind_protect to return to the previous
  state later.

  If Emacs is already in single_kboard mode, and F's keyboard is
  locked, then this function will throw an errow.  */
909 910

void
911
temporarily_switch_to_single_kboard (struct frame *f)
912 913
{
  int was_locked = single_kboard;