aboutsummaryrefslogtreecommitdiff
path: root/gdb/tui/tui-io.c
blob: 6f81f0980ff73788fafd5f502b2fcd9dc46d55f0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
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
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
/* TUI support I/O functions.

   Copyright (C) 1998-2015 Free Software Foundation, Inc.

   Contributed by Hewlett-Packard Company.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program 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
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include "defs.h"
#include "target.h"
#include "event-loop.h"
#include "event-top.h"
#include "command.h"
#include "top.h"
#include "tui/tui.h"
#include "tui/tui-data.h"
#include "tui/tui-io.h"
#include "tui/tui-command.h"
#include "tui/tui-win.h"
#include "tui/tui-wingeneral.h"
#include "tui/tui-file.h"
#include "ui-out.h"
#include "cli-out.h"
#include <fcntl.h>
#include <signal.h>
#include "filestuff.h"
#include "completer.h"
#include "gdb_curses.h"

/* This redefines CTRL if it is not already defined, so it must come
   after terminal state releated include files like <term.h> and
   "gdb_curses.h".  */
#include "readline/readline.h"

int
key_is_start_sequence (int ch)
{
  return (ch == 27);
}

int
key_is_end_sequence (int ch)
{
  return (ch == 126);
}

int
key_is_backspace (int ch)
{
  return (ch == 8);
}

/* Use definition from readline 4.3.  */
#undef CTRL_CHAR
#define CTRL_CHAR(c) \
     ((c) < control_character_threshold && (((c) & 0x80) == 0))

/* This file controls the IO interactions between gdb and curses.
   When the TUI is enabled, gdb has two modes a curses and a standard
   mode.

   In curses mode, the gdb outputs are made in a curses command
   window.  For this, the gdb_stdout and gdb_stderr are redirected to
   the specific ui_file implemented by TUI.  The output is handled by
   tui_puts().  The input is also controlled by curses with
   tui_getc().  The readline library uses this function to get its
   input.  Several readline hooks are installed to redirect readline
   output to the TUI (see also the note below).

   In normal mode, the gdb outputs are restored to their origin, that
   is as if TUI is not used.  Readline also uses its original getc()
   function with stdin.

   Note SCz/2001-07-21: the current readline is not clean in its
   management of the output.  Even if we install a redisplay handler,
   it sometimes writes on a stdout file.  It is important to redirect
   every output produced by readline, otherwise the curses window will
   be garbled.  This is implemented with a pipe that TUI reads and
   readline writes to.  A gdb input handler is created so that reading
   the pipe is handled automatically.  This will probably not work on
   non-Unix platforms.  The best fix is to make readline clean enougth
   so that is never write on stdout.

   Note SCz/2002-09-01: we now use more readline hooks and it seems
   that with them we don't need the pipe anymore (verified by creating
   the pipe and closing its end so that write causes a SIGPIPE).  The
   old pipe code is still there and can be conditionally removed by
   #undef TUI_USE_PIPE_FOR_READLINE.  */

/* For gdb 5.3, prefer to continue the pipe hack as a backup wheel.  */
#ifdef HAVE_PIPE
#define TUI_USE_PIPE_FOR_READLINE
#endif
/* #undef TUI_USE_PIPE_FOR_READLINE */

/* TUI output files.  */
static struct ui_file *tui_stdout;
static struct ui_file *tui_stderr;
struct ui_out *tui_out;

/* GDB output files in non-curses mode.  */
static struct ui_file *tui_old_stdout;
static struct ui_file *tui_old_stderr;
struct ui_out *tui_old_uiout;

/* Readline previous hooks.  */
static rl_getc_func_t *tui_old_rl_getc_function;
static rl_voidfunc_t *tui_old_rl_redisplay_function;
static rl_vintfunc_t *tui_old_rl_prep_terminal;
static rl_voidfunc_t *tui_old_rl_deprep_terminal;
static rl_compdisp_func_t *tui_old_rl_display_matches_hook;
static int tui_old_rl_echoing_p;

/* Readline output stream.
   Should be removed when readline is clean.  */
static FILE *tui_rl_outstream;
static FILE *tui_old_rl_outstream;
#ifdef TUI_USE_PIPE_FOR_READLINE
static int tui_readline_pipe[2];
#endif

/* The last gdb prompt that was registered in readline.
   This may be the main gdb prompt or a secondary prompt.  */
static char *tui_rl_saved_prompt;

static void
tui_putc (char c)
{
  char buf[2];

  buf[0] = c;
  buf[1] = 0;
  tui_puts (buf);
}

/* Print the string in the curses command window.
   The output is buffered.  It is up to the caller to refresh the screen
   if necessary.  */

void
tui_puts (const char *string)
{
  static int tui_skip_line = -1;
  char c;
  WINDOW *w;

  w = TUI_CMD_WIN->generic.handle;
  while ((c = *string++) != 0)
    {
      /* Catch annotation and discard them.  We need two \032 and
         discard until a \n is seen.  */
      if (c == '\032')
        {
          tui_skip_line++;
        }
      else if (tui_skip_line != 1)
        {
          tui_skip_line = -1;
	  /* Expand TABs, since ncurses on MS-Windows doesn't.  */
	  if (c == '\t')
	    {
	      int line, col;

	      getyx (w, line, col);
	      do
		{
		  waddch (w, ' ');
		  col++;
		} while ((col % 8) != 0);
	    }
	  else
	    waddch (w, c);
        }
      else if (c == '\n')
        tui_skip_line = -1;
    }
  TUI_CMD_WIN->detail.command_info.start_line = getcury (w);
}

/* Readline callback.
   Redisplay the command line with its prompt after readline has
   changed the edited text.  */
void
tui_redisplay_readline (void)
{
  int prev_col;
  int height;
  int col, line;
  int c_pos;
  int c_line;
  int in;
  WINDOW *w;
  char *prompt;
  int start_line;

  /* Detect when we temporarily left SingleKey and now the readline
     edit buffer is empty, automatically restore the SingleKey
     mode.  The restore must only be done if the command has finished.
     The command could call prompt_for_continue and we must not
     restore SingleKey so that the prompt and normal keymap are used.  */
  if (tui_current_key_mode == TUI_ONE_COMMAND_MODE && rl_end == 0
      && immediate_quit == 0)
    tui_set_key_mode (TUI_SINGLE_KEY_MODE);

  if (tui_current_key_mode == TUI_SINGLE_KEY_MODE)
    prompt = "";
  else
    prompt = tui_rl_saved_prompt;
  
  c_pos = -1;
  c_line = -1;
  w = TUI_CMD_WIN->generic.handle;
  start_line = TUI_CMD_WIN->detail.command_info.start_line;
  wmove (w, start_line, 0);
  prev_col = 0;
  height = 1;
  for (in = 0; prompt && prompt[in]; in++)
    {
      waddch (w, prompt[in]);
      getyx (w, line, col);
      if (col <= prev_col)
        height++;
      prev_col = col;
    }
  for (in = 0; in <= rl_end; in++)
    {
      unsigned char c;
      
      if (in == rl_point)
	{
          getyx (w, c_line, c_pos);
	}

      if (in == rl_end)
        break;

      c = (unsigned char) rl_line_buffer[in];
      if (CTRL_CHAR (c) || c == RUBOUT)
	{
          waddch (w, '^');
          waddch (w, CTRL_CHAR (c) ? UNCTRL (c) : '?');
	}
      else if (c == '\t')
	{
	  /* Expand TABs, since ncurses on MS-Windows doesn't.  */
	  getyx (w, line, col);
	  do
	    {
	      waddch (w, ' ');
	      col++;
	    } while ((col % 8) != 0);
	}
      else
	{
          waddch (w, c);
	}
      if (c == '\n')
	TUI_CMD_WIN->detail.command_info.start_line = getcury (w);
      getyx (w, line, col);
      if (col < prev_col)
        height++;
      prev_col = col;
    }
  wclrtobot (w);
  TUI_CMD_WIN->detail.command_info.start_line = getcury (w);
  if (c_line >= 0)
    wmove (w, c_line, c_pos);
  TUI_CMD_WIN->detail.command_info.start_line -= height - 1;

  wrefresh (w);
  fflush(stdout);
}

/* Readline callback to prepare the terminal.  It is called once each
   time we enter readline.  Terminal is already setup in curses
   mode.  */
static void
tui_prep_terminal (int notused1)
{
  /* Save the prompt registered in readline to correctly display it.
     (we can't use gdb_prompt() due to secondary prompts and can't use
     rl_prompt because it points to an alloca buffer).  */
  xfree (tui_rl_saved_prompt);
  tui_rl_saved_prompt = rl_prompt != NULL ? xstrdup (rl_prompt) : NULL;
}

/* Readline callback to restore the terminal.  It is called once each
   time we leave readline.  There is nothing to do in curses mode.  */
static void
tui_deprep_terminal (void)
{
}

#ifdef TUI_USE_PIPE_FOR_READLINE
/* Read readline output pipe and feed the command window with it.
   Should be removed when readline is clean.  */
static void
tui_readline_output (int error, gdb_client_data data)
{
  int size;
  char buf[256];

  size = read (tui_readline_pipe[0], buf, sizeof (buf) - 1);
  if (size > 0 && tui_active)
    {
      buf[size] = 0;
      tui_puts (buf);
    }
}
#endif

/* TUI version of displayer.crlf.  */

static void
tui_mld_crlf (const struct match_list_displayer *displayer)
{
  tui_putc ('\n');
}

/* TUI version of displayer.putch.  */

static void
tui_mld_putch (const struct match_list_displayer *displayer, int ch)
{
  tui_putc (ch);
}

/* TUI version of displayer.puts.  */

static void
tui_mld_puts (const struct match_list_displayer *displayer, const char *s)
{
  tui_puts (s);
}

/* TUI version of displayer.flush.  */

static void
tui_mld_flush (const struct match_list_displayer *displayer)
{
  wrefresh (TUI_CMD_WIN->generic.handle);
}

/* TUI version of displayer.erase_entire_line.  */

static void
tui_mld_erase_entire_line (const struct match_list_displayer *displayer)
{
  WINDOW *w = TUI_CMD_WIN->generic.handle;
  int cur_y = getcury (w);

  wmove (w, cur_y, 0);
  wclrtoeol (w);
  wmove (w, cur_y, 0);
}

/* TUI version of displayer.beep.  */

static void
tui_mld_beep (const struct match_list_displayer *displayer)
{
  beep ();
}

/* Helper function for tui_mld_read_key.
   This temporarily replaces tui_getc for use during tab-completion
   match list display.  */

static int
tui_mld_getc (FILE *fp)
{
  WINDOW *w = TUI_CMD_WIN->generic.handle;
  int c = wgetch (w);

  return c;
}

/* TUI version of displayer.read_key.  */

static int
tui_mld_read_key (const struct match_list_displayer *displayer)
{
  rl_getc_func_t *prev = rl_getc_function;
  int c;

  /* We can't use tui_getc as we need NEWLINE to not get emitted.  */
  rl_getc_function = tui_mld_getc;
  c = rl_read_key ();
  rl_getc_function = prev;
  return c;
}

/* TUI version of rl_completion_display_matches_hook.
   See gdb_display_match_list for a description of the arguments.  */

static void
tui_rl_display_match_list (char **matches, int len, int max)
{
  struct match_list_displayer displayer;

  rl_get_screen_size (&displayer.height, &displayer.width);
  displayer.crlf = tui_mld_crlf;
  displayer.putch = tui_mld_putch;
  displayer.puts = tui_mld_puts;
  displayer.flush = tui_mld_flush;
  displayer.erase_entire_line = tui_mld_erase_entire_line;
  displayer.beep = tui_mld_beep;
  displayer.read_key = tui_mld_read_key;

  gdb_display_match_list (matches, len, max, &displayer);
}

/* Setup the IO for curses or non-curses mode.
   - In non-curses mode, readline and gdb use the standard input and
   standard output/error directly.
   - In curses mode, the standard output/error is controlled by TUI
   with the tui_stdout and tui_stderr.  The output is redirected in
   the curses command window.  Several readline callbacks are installed
   so that readline asks for its input to the curses command window
   with wgetch().  */
void
tui_setup_io (int mode)
{
  extern int _rl_echoing_p;

  if (mode)
    {
      /* Redirect readline to TUI.  */
      tui_old_rl_redisplay_function = rl_redisplay_function;
      tui_old_rl_deprep_terminal = rl_deprep_term_function;
      tui_old_rl_prep_terminal = rl_prep_term_function;
      tui_old_rl_getc_function = rl_getc_function;
      tui_old_rl_display_matches_hook = rl_completion_display_matches_hook;
      tui_old_rl_outstream = rl_outstream;
      tui_old_rl_echoing_p = _rl_echoing_p;
      rl_redisplay_function = tui_redisplay_readline;
      rl_deprep_term_function = tui_deprep_terminal;
      rl_prep_term_function = tui_prep_terminal;
      rl_getc_function = tui_getc;
      _rl_echoing_p = 0;
      rl_outstream = tui_rl_outstream;
      rl_prompt = 0;
      rl_completion_display_matches_hook = tui_rl_display_match_list;
      rl_already_prompted = 0;

      /* Keep track of previous gdb output.  */
      tui_old_stdout = gdb_stdout;
      tui_old_stderr = gdb_stderr;
      tui_old_uiout = current_uiout;

      /* Reconfigure gdb output.  */
      gdb_stdout = tui_stdout;
      gdb_stderr = tui_stderr;
      gdb_stdlog = gdb_stdout;	/* for moment */
      gdb_stdtarg = gdb_stderr;	/* for moment */
      gdb_stdtargerr = gdb_stderr;	/* for moment */
      current_uiout = tui_out;

      /* Save tty for SIGCONT.  */
      savetty ();
    }
  else
    {
      /* Restore gdb output.  */
      gdb_stdout = tui_old_stdout;
      gdb_stderr = tui_old_stderr;
      gdb_stdlog = gdb_stdout;	/* for moment */
      gdb_stdtarg = gdb_stderr;	/* for moment */
      gdb_stdtargerr = gdb_stderr;	/* for moment */
      current_uiout = tui_old_uiout;

      /* Restore readline.  */
      rl_redisplay_function = tui_old_rl_redisplay_function;
      rl_deprep_term_function = tui_old_rl_deprep_terminal;
      rl_prep_term_function = tui_old_rl_prep_terminal;
      rl_getc_function = tui_old_rl_getc_function;
      rl_completion_display_matches_hook = tui_old_rl_display_matches_hook;
      rl_outstream = tui_old_rl_outstream;
      _rl_echoing_p = tui_old_rl_echoing_p;
      rl_already_prompted = 0;

      /* Save tty for SIGCONT.  */
      savetty ();
    }
}

#ifdef SIGCONT
/* Catch SIGCONT to restore the terminal and refresh the screen.  */
static void
tui_cont_sig (int sig)
{
  if (tui_active)
    {
      /* Restore the terminal setting because another process (shell)
         might have changed it.  */
      resetty ();

      /* Force a refresh of the screen.  */
      tui_refresh_all_win ();

      wrefresh (TUI_CMD_WIN->generic.handle);
    }
  signal (sig, tui_cont_sig);
}
#endif

/* Initialize the IO for gdb in curses mode.  */
void
tui_initialize_io (void)
{
#ifdef SIGCONT
  signal (SIGCONT, tui_cont_sig);
#endif

  /* Create tui output streams.  */
  tui_stdout = tui_fileopen (stdout);
  tui_stderr = tui_fileopen (stderr);
  tui_out = tui_out_new (tui_stdout);

  /* Create the default UI.  */
  tui_old_uiout = cli_out_new (gdb_stdout);

#ifdef TUI_USE_PIPE_FOR_READLINE
  /* Temporary solution for readline writing to stdout: redirect
     readline output in a pipe, read that pipe and output the content
     in the curses command window.  */
  if (gdb_pipe_cloexec (tui_readline_pipe) != 0)
    error (_("Cannot create pipe for readline"));

  tui_rl_outstream = fdopen (tui_readline_pipe[1], "w");
  if (tui_rl_outstream == 0)
    error (_("Cannot redirect readline output"));

  setvbuf (tui_rl_outstream, (char*) NULL, _IOLBF, 0);

#ifdef O_NONBLOCK
  (void) fcntl (tui_readline_pipe[0], F_SETFL, O_NONBLOCK);
#else
#ifdef O_NDELAY
  (void) fcntl (tui_readline_pipe[0], F_SETFL, O_NDELAY);
#endif
#endif
  add_file_handler (tui_readline_pipe[0], tui_readline_output, 0);
#else
  tui_rl_outstream = stdout;
#endif
}

/* Get a character from the command window.  This is called from the
   readline package.  */
int
tui_getc (FILE *fp)
{
  int ch;
  WINDOW *w;

  w = TUI_CMD_WIN->generic.handle;

#ifdef TUI_USE_PIPE_FOR_READLINE
  /* Flush readline output.  */
  tui_readline_output (0, 0);
#endif

  ch = wgetch (w);

  /* The \n must be echoed because it will not be printed by
     readline.  */
  if (ch == '\n')
    {
      /* When hitting return with an empty input, gdb executes the last
         command.  If we emit a newline, this fills up the command window
         with empty lines with gdb prompt at beginning.  Instead of that,
         stay on the same line but provide a visual effect to show the
         user we recognized the command.  */
      if (rl_end == 0 && !gdb_in_secondary_prompt_p ())
        {
	  wmove (w, getcury (w), 0);

          /* Clear the line.  This will blink the gdb prompt since
             it will be redrawn at the same line.  */
          wclrtoeol (w);
          wrefresh (w);
          napms (20);
        }
      else
        {
	  /* Move cursor to the end of the command line before emitting the
	     newline.  We need to do so because when ncurses outputs a newline
	     it truncates any text that appears past the end of the cursor.  */
	  int px, py;
	  getyx (w, py, px);
	  px += rl_end - rl_point;
	  py += px / TUI_CMD_WIN->generic.width;
	  px %= TUI_CMD_WIN->generic.width;
	  wmove (w, py, px);
	  tui_putc ('\n');
        }
    }
  
  /* Handle prev/next/up/down here.  */
  ch = tui_dispatch_ctrl_char (ch);
  
  if (ch == KEY_BACKSPACE)
    return '\b';

  if (async_command_editing_p && key_is_start_sequence (ch))
    {
      int ch_pending;

      nodelay (w, TRUE);
      ch_pending = wgetch (w);
      nodelay (w, FALSE);

      /* If we have pending input following a start sequence, call the stdin
	 event handler again because ncurses may have already read and stored
	 the input into its internal buffer, meaning that we won't get an stdin
	 event for it.  If we don't compensate for this missed stdin event, key
	 sequences as Alt_F (^[f) will not behave promptly.

	 (We only compensates for the missed 2nd byte of a key sequence because
	 2-byte sequences are by far the most commonly used. ncurses may have
	 buffered a larger, 3+-byte key sequence though it remains to be seen
	 whether it is useful to compensate for all the bytes of such
	 sequences.)  */
      if (ch_pending != ERR)
	{
	  ungetch (ch_pending);
	  call_stdin_event_handler_again_p = 1;
	}
    }

  return ch;
}

/* Utility function to expand TABs in a STRING into spaces.  STRING
   will be displayed starting at column COL, and is assumed to include
   no newlines.  The returned expanded string is malloc'ed.  */

char *
tui_expand_tabs (const char *string, int col)
{
  int n_adjust, ncol;
  const char *s;
  char *ret, *q;

  /* 1. How many additional characters do we need?  */
  for (ncol = col, n_adjust = 0, s = string; s; )
    {
      s = strpbrk (s, "\t");
      if (s)
	{
	  ncol += (s - string) + n_adjust;
	  /* Adjustment for the next tab stop, minus one for the TAB
	     we replace with spaces.  */
	  n_adjust += 8 - (ncol % 8) - 1;
	  s++;
	}
    }

  /* Allocate the copy.  */
  ret = q = (char *) xmalloc (strlen (string) + n_adjust + 1);

  /* 2. Copy the original string while replacing TABs with spaces.  */
  for (ncol = col, s = string; s; )
    {
      const char *s1 = strpbrk (s, "\t");
      if (s1)
	{
	  if (s1 > s)
	    {
	      strncpy (q, s, s1 - s);
	      q += s1 - s;
	      ncol += s1 - s;
	    }
	  do {
	    *q++ = ' ';
	    ncol++;
	  } while ((ncol % 8) != 0);
	  s1++;
	}
      else
	strcpy (q, s);
      s = s1;
    }

  return ret;
}