aboutsummaryrefslogtreecommitdiff
path: root/gdb/inflow.c
blob: 99cc955d04fb7860db00a44861d222dbc1ede525 (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
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
/* Low level interface to ptrace, for GDB when running under Unix.
   Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
   1996, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
   Free Software Foundation, Inc.

   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 "frame.h"
#include "inferior.h"
#include "command.h"
#include "serial.h"
#include "terminal.h"
#include "target.h"
#include "gdbthread.h"

#include "gdb_string.h"
#include <signal.h>
#include <fcntl.h>
#include "gdb_select.h"

#include "inflow.h"

#ifdef HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif

#ifndef O_NOCTTY
#define O_NOCTTY 0
#endif

#if defined (SIGIO) && defined (FASYNC) && defined (FD_SET) && defined (F_SETOWN)
static void handle_sigio (int);
#endif

extern void _initialize_inflow (void);

static void pass_signal (int);

static void kill_command (char *, int);

static void terminal_ours_1 (int);

/* Record terminal status separately for debugger and inferior.  */

static struct serial *stdin_serial;

/* TTY state for the inferior.  We save it whenever the inferior stops, and
   restore it when it resumes.  */
static serial_ttystate inferior_ttystate;

/* Our own tty state, which we restore every time we need to deal with the
   terminal.  We only set it once, when GDB first starts.  The settings of
   flags which readline saves and restores and unimportant.  */
static serial_ttystate our_ttystate;

/* fcntl flags for us and the inferior.  Saved and restored just like
   {our,inferior}_ttystate.  */
static int tflags_inferior;
static int tflags_ours;

#ifdef PROCESS_GROUP_TYPE
/* Process group for us and the inferior.  Saved and restored just like
   {our,inferior}_ttystate.  */
PROCESS_GROUP_TYPE our_process_group;
PROCESS_GROUP_TYPE inferior_process_group;
#endif

/* While the inferior is running, we want SIGINT and SIGQUIT to go to the
   inferior only.  If we have job control, that takes care of it.  If not,
   we save our handlers in these two variables and set SIGINT and SIGQUIT
   to SIG_IGN.  */

static void (*sigint_ours) ();
static void (*sigquit_ours) ();

/* The name of the tty (from the `tty' command) that we gave to the inferior
   when it was last started.  */

static const char *inferior_thisrun_terminal;

/* Nonzero if our terminal settings are in effect.  Zero if the
   inferior's settings are in effect.  Ignored if !gdb_has_a_terminal
   ().  */

int terminal_is_ours;

enum
  {
    yes, no, have_not_checked
  }
gdb_has_a_terminal_flag = have_not_checked;

/* Does GDB have a terminal (on stdin)?  */
int
gdb_has_a_terminal (void)
{
  switch (gdb_has_a_terminal_flag)
    {
    case yes:
      return 1;
    case no:
      return 0;
    case have_not_checked:
      /* Get all the current tty settings (including whether we have a
         tty at all!).  Can't do this in _initialize_inflow because
         serial_fdopen() won't work until the serial_ops_list is
         initialized.  */

#ifdef F_GETFL
      tflags_ours = fcntl (0, F_GETFL, 0);
#endif

      gdb_has_a_terminal_flag = no;
      if (stdin_serial != NULL)
	{
	  our_ttystate = serial_get_tty_state (stdin_serial);

	  if (our_ttystate != NULL)
	    {
	      gdb_has_a_terminal_flag = yes;
#ifdef HAVE_TERMIOS
	      our_process_group = tcgetpgrp (0);
#endif
#ifdef HAVE_TERMIO
	      our_process_group = getpgrp ();
#endif
#ifdef HAVE_SGTTY
	      ioctl (0, TIOCGPGRP, &our_process_group);
#endif
	    }
	}

      return gdb_has_a_terminal_flag == yes;
    default:
      /* "Can't happen".  */
      return 0;
    }
}

/* Macro for printing errors from ioctl operations */

#define	OOPSY(what)	\
  if (result == -1)	\
    fprintf_unfiltered(gdb_stderr, "[%s failed in terminal_inferior: %s]\n", \
	    what, safe_strerror (errno))

static void terminal_ours_1 (int);

/* Initialize the terminal settings we record for the inferior,
   before we actually run the inferior.  */

void
terminal_init_inferior_with_pgrp (int pgrp)
{
  if (gdb_has_a_terminal ())
    {
      /* We could just as well copy our_ttystate (if we felt like
         adding a new function serial_copy_tty_state()).  */
      if (inferior_ttystate)
	xfree (inferior_ttystate);
      inferior_ttystate = serial_get_tty_state (stdin_serial);

#ifdef PROCESS_GROUP_TYPE
      inferior_process_group = pgrp;
#endif

      /* Make sure that next time we call terminal_inferior (which will be
         before the program runs, as it needs to be), we install the new
         process group.  */
      terminal_is_ours = 1;
    }
}

/* Save the terminal settings again.  This is necessary for the TUI
   when it switches to TUI or non-TUI mode;  curses changes the terminal
   and gdb must be able to restore it correctly.  */

void
terminal_save_ours (void)
{
  if (gdb_has_a_terminal ())
    {
      /* We could just as well copy our_ttystate (if we felt like adding
         a new function serial_copy_tty_state).  */
      if (our_ttystate)
        xfree (our_ttystate);
      our_ttystate = serial_get_tty_state (stdin_serial);
    }
}

void
terminal_init_inferior (void)
{
#ifdef PROCESS_GROUP_TYPE
  /* This is for Lynx, and should be cleaned up by having Lynx be a separate
     debugging target with a version of target_terminal_init_inferior which
     passes in the process group to a generic routine which does all the work
     (and the non-threaded child_terminal_init_inferior can just pass in
     inferior_ptid to the same routine).  */
  /* We assume INFERIOR_PID is also the child's process group.  */
  terminal_init_inferior_with_pgrp (PIDGET (inferior_ptid));
#endif /* PROCESS_GROUP_TYPE */
}

/* Put the inferior's terminal settings into effect.
   This is preparation for starting or resuming the inferior.  */

void
terminal_inferior (void)
{
  if (gdb_has_a_terminal () && terminal_is_ours
      && inferior_ttystate != NULL
      && inferior_thisrun_terminal == 0)
    {
      int result;

#ifdef F_GETFL
      /* Is there a reason this is being done twice?  It happens both
         places we use F_SETFL, so I'm inclined to think perhaps there
         is some reason, however perverse.  Perhaps not though...  */
      result = fcntl (0, F_SETFL, tflags_inferior);
      result = fcntl (0, F_SETFL, tflags_inferior);
      OOPSY ("fcntl F_SETFL");
#endif

      /* Because we were careful to not change in or out of raw mode in
         terminal_ours, we will not change in our out of raw mode with
         this call, so we don't flush any input.  */
      result = serial_set_tty_state (stdin_serial, inferior_ttystate);
      OOPSY ("setting tty state");

      if (!job_control)
	{
	  sigint_ours = (void (*)()) signal (SIGINT, SIG_IGN);
#ifdef SIGQUIT
	  sigquit_ours = (void (*)()) signal (SIGQUIT, SIG_IGN);
#endif
	}

      /* If attach_flag is set, we don't know whether we are sharing a
         terminal with the inferior or not.  (attaching a process
         without a terminal is one case where we do not; attaching a
         process which we ran from the same shell as GDB via `&' is
         one case where we do, I think (but perhaps this is not
         `sharing' in the sense that we need to save and restore tty
         state)).  I don't know if there is any way to tell whether we
         are sharing a terminal.  So what we do is to go through all
         the saving and restoring of the tty state, but ignore errors
         setting the process group, which will happen if we are not
         sharing a terminal).  */

      if (job_control)
	{
#ifdef HAVE_TERMIOS
	  result = tcsetpgrp (0, inferior_process_group);
	  if (!attach_flag)
	    OOPSY ("tcsetpgrp");
#endif

#ifdef HAVE_SGTTY
	  result = ioctl (0, TIOCSPGRP, &inferior_process_group);
	  if (!attach_flag)
	    OOPSY ("TIOCSPGRP");
#endif
	}

    }
  terminal_is_ours = 0;
}

/* Put some of our terminal settings into effect,
   enough to get proper results from our output,
   but do not change into or out of RAW mode
   so that no input is discarded.

   After doing this, either terminal_ours or terminal_inferior
   should be called to get back to a normal state of affairs.  */

void
terminal_ours_for_output (void)
{
  terminal_ours_1 (1);
}

/* Put our terminal settings into effect.
   First record the inferior's terminal settings
   so they can be restored properly later.  */

void
terminal_ours (void)
{
  terminal_ours_1 (0);
}

/* output_only is not used, and should not be used unless we introduce
   separate terminal_is_ours and terminal_is_ours_for_output
   flags.  */

static void
terminal_ours_1 (int output_only)
{
  /* Checking inferior_thisrun_terminal is necessary so that
     if GDB is running in the background, it won't block trying
     to do the ioctl()'s below.  Checking gdb_has_a_terminal
     avoids attempting all the ioctl's when running in batch.  */
  if (inferior_thisrun_terminal != 0 || gdb_has_a_terminal () == 0)
    return;

  if (!terminal_is_ours)
    {
#ifdef SIGTTOU
      /* Ignore this signal since it will happen when we try to set the
         pgrp.  */
      void (*osigttou) () = NULL;
#endif
      int result;

      terminal_is_ours = 1;

#ifdef SIGTTOU
      if (job_control)
	osigttou = (void (*)()) signal (SIGTTOU, SIG_IGN);
#endif

      if (inferior_ttystate)
	xfree (inferior_ttystate);
      inferior_ttystate = serial_get_tty_state (stdin_serial);
#ifdef HAVE_TERMIOS
      inferior_process_group = tcgetpgrp (0);
#endif
#ifdef HAVE_TERMIO
      inferior_process_group = getpgrp ();
#endif
#ifdef HAVE_SGTTY
      ioctl (0, TIOCGPGRP, &inferior_process_group);
#endif

      /* Here we used to set ICANON in our ttystate, but I believe this
         was an artifact from before when we used readline.  Readline sets
         the tty state when it needs to.
         FIXME-maybe: However, query() expects non-raw mode and doesn't
         use readline.  Maybe query should use readline (on the other hand,
         this only matters for HAVE_SGTTY, not termio or termios, I think).  */

      /* Set tty state to our_ttystate.  We don't change in our out of raw
         mode, to avoid flushing input.  We need to do the same thing
         regardless of output_only, because we don't have separate
         terminal_is_ours and terminal_is_ours_for_output flags.  It's OK,
         though, since readline will deal with raw mode when/if it needs to.
       */

      serial_noflush_set_tty_state (stdin_serial, our_ttystate,
				    inferior_ttystate);

      if (job_control)
	{
#ifdef HAVE_TERMIOS
	  result = tcsetpgrp (0, our_process_group);
#if 0
	  /* This fails on Ultrix with EINVAL if you run the testsuite
	     in the background with nohup, and then log out.  GDB never
	     used to check for an error here, so perhaps there are other
	     such situations as well.  */
	  if (result == -1)
	    fprintf_unfiltered (gdb_stderr, "[tcsetpgrp failed in terminal_ours: %s]\n",
				safe_strerror (errno));
#endif
#endif /* termios */

#ifdef HAVE_SGTTY
	  result = ioctl (0, TIOCSPGRP, &our_process_group);
#endif
	}

#ifdef SIGTTOU
      if (job_control)
	signal (SIGTTOU, osigttou);
#endif

      if (!job_control)
	{
	  signal (SIGINT, sigint_ours);
#ifdef SIGQUIT
	  signal (SIGQUIT, sigquit_ours);
#endif
	}

#ifdef F_GETFL
      tflags_inferior = fcntl (0, F_GETFL, 0);

      /* Is there a reason this is being done twice?  It happens both
         places we use F_SETFL, so I'm inclined to think perhaps there
         is some reason, however perverse.  Perhaps not though...  */
      result = fcntl (0, F_SETFL, tflags_ours);
      result = fcntl (0, F_SETFL, tflags_ours);
#endif
    }
}

void
term_info (char *arg, int from_tty)
{
  target_terminal_info (arg, from_tty);
}

void
child_terminal_info (char *args, int from_tty)
{
  if (!gdb_has_a_terminal ())
    {
      printf_filtered (_("This GDB does not control a terminal.\n"));
      return;
    }

  printf_filtered (_("Inferior's terminal status (currently saved by GDB):\n"));

  /* First the fcntl flags.  */
  {
    int flags;

    flags = tflags_inferior;

    printf_filtered ("File descriptor flags = ");

#ifndef O_ACCMODE
#define O_ACCMODE (O_RDONLY | O_WRONLY | O_RDWR)
#endif
    /* (O_ACCMODE) parens are to avoid Ultrix header file bug */
    switch (flags & (O_ACCMODE))
      {
      case O_RDONLY:
	printf_filtered ("O_RDONLY");
	break;
      case O_WRONLY:
	printf_filtered ("O_WRONLY");
	break;
      case O_RDWR:
	printf_filtered ("O_RDWR");
	break;
      }
    flags &= ~(O_ACCMODE);

#ifdef O_NONBLOCK
    if (flags & O_NONBLOCK)
      printf_filtered (" | O_NONBLOCK");
    flags &= ~O_NONBLOCK;
#endif

#if defined (O_NDELAY)
    /* If O_NDELAY and O_NONBLOCK are defined to the same thing, we will
       print it as O_NONBLOCK, which is good cause that is what POSIX
       has, and the flag will already be cleared by the time we get here.  */
    if (flags & O_NDELAY)
      printf_filtered (" | O_NDELAY");
    flags &= ~O_NDELAY;
#endif

    if (flags & O_APPEND)
      printf_filtered (" | O_APPEND");
    flags &= ~O_APPEND;

#if defined (O_BINARY)
    if (flags & O_BINARY)
      printf_filtered (" | O_BINARY");
    flags &= ~O_BINARY;
#endif

    if (flags)
      printf_filtered (" | 0x%x", flags);
    printf_filtered ("\n");
  }

#ifdef PROCESS_GROUP_TYPE
  printf_filtered ("Process group = %d\n",
		   (int) inferior_process_group);
#endif

  serial_print_tty_state (stdin_serial, inferior_ttystate, gdb_stdout);
}

/* NEW_TTY_PREFORK is called before forking a new child process,
   so we can record the state of ttys in the child to be formed.
   TTYNAME is null if we are to share the terminal with gdb;
   or points to a string containing the name of the desired tty.

   NEW_TTY is called in new child processes under Unix, which will
   become debugger target processes.  This actually switches to
   the terminal specified in the NEW_TTY_PREFORK call.  */

void
new_tty_prefork (const char *ttyname)
{
  /* Save the name for later, for determining whether we and the child
     are sharing a tty.  */
  inferior_thisrun_terminal = ttyname;
}

void
new_tty (void)
{
  int tty;

  if (inferior_thisrun_terminal == 0)
    return;
#if !defined(__GO32__) && !defined(_WIN32)
#ifdef TIOCNOTTY
  /* Disconnect the child process from our controlling terminal.  On some
     systems (SVR4 for example), this may cause a SIGTTOU, so temporarily
     ignore SIGTTOU. */
  tty = open ("/dev/tty", O_RDWR);
  if (tty > 0)
    {
      void (*osigttou) ();

      osigttou = (void (*)()) signal (SIGTTOU, SIG_IGN);
      ioctl (tty, TIOCNOTTY, 0);
      close (tty);
      signal (SIGTTOU, osigttou);
    }
#endif

  /* Now open the specified new terminal.  */
  tty = open (inferior_thisrun_terminal, O_RDWR | O_NOCTTY);
  if (tty == -1)
    {
      print_sys_errmsg (inferior_thisrun_terminal, errno);
      _exit (1);
    }

  /* Avoid use of dup2; doesn't exist on all systems.  */
  if (tty != 0)
    {
      close (0);
      dup (tty);
    }
  if (tty != 1)
    {
      close (1);
      dup (tty);
    }
  if (tty != 2)
    {
      close (2);
      dup (tty);
    }
  if (tty > 2)
    close (tty);
#endif /* !go32 && !win32 */
}

/* Kill the inferior process.  Make us have no inferior.  */

static void
kill_command (char *arg, int from_tty)
{
  /* FIXME:  This should not really be inferior_ptid (or target_has_execution).
     It should be a distinct flag that indicates that a target is active, cuz
     some targets don't have processes! */

  if (ptid_equal (inferior_ptid, null_ptid))
    error (_("The program is not being run."));
  if (!query ("Kill the program being debugged? "))
    error (_("Not confirmed."));
  target_kill ();

  init_thread_list ();		/* Destroy thread info */

  /* Killing off the inferior can leave us with a core file.  If so,
     print the state we are left in.  */
  if (target_has_stack)
    {
      printf_filtered (_("In %s,\n"), target_longname);
      print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC);
    }
  bfd_cache_close_all ();
}

/* Call set_sigint_trap when you need to pass a signal on to an attached
   process when handling SIGINT */

static void
pass_signal (int signo)
{
#ifndef _WIN32
  kill (PIDGET (inferior_ptid), SIGINT);
#endif
}

static void (*osig) ();

void
set_sigint_trap (void)
{
  if (attach_flag || inferior_thisrun_terminal)
    {
      osig = (void (*)()) signal (SIGINT, pass_signal);
    }
}

void
clear_sigint_trap (void)
{
  if (attach_flag || inferior_thisrun_terminal)
    {
      signal (SIGINT, osig);
    }
}

#if defined (SIGIO) && defined (FASYNC) && defined (FD_SET) && defined (F_SETOWN)
static void (*old_sigio) ();

static void
handle_sigio (int signo)
{
  int numfds;
  fd_set readfds;

  signal (SIGIO, handle_sigio);

  FD_ZERO (&readfds);
  FD_SET (target_activity_fd, &readfds);
  numfds = gdb_select (target_activity_fd + 1, &readfds, NULL, NULL, NULL);
  if (numfds >= 0 && FD_ISSET (target_activity_fd, &readfds))
    {
#ifndef _WIN32
      if ((*target_activity_function) ())
	kill (PIDGET (inferior_ptid), SIGINT);
#endif
    }
}

static int old_fcntl_flags;

void
set_sigio_trap (void)
{
  if (target_activity_function)
    {
      old_sigio = (void (*)()) signal (SIGIO, handle_sigio);
      fcntl (target_activity_fd, F_SETOWN, getpid ());
      old_fcntl_flags = fcntl (target_activity_fd, F_GETFL, 0);
      fcntl (target_activity_fd, F_SETFL, old_fcntl_flags | FASYNC);
    }
}

void
clear_sigio_trap (void)
{
  if (target_activity_function)
    {
      signal (SIGIO, old_sigio);
      fcntl (target_activity_fd, F_SETFL, old_fcntl_flags);
    }
}
#else /* No SIGIO.  */
void
set_sigio_trap (void)
{
  if (target_activity_function)
    internal_error (__FILE__, __LINE__, _("failed internal consistency check"));
}

void
clear_sigio_trap (void)
{
  if (target_activity_function)
    internal_error (__FILE__, __LINE__, _("failed internal consistency check"));
}
#endif /* No SIGIO.  */


/* This is here because this is where we figure out whether we (probably)
   have job control.  Just using job_control only does part of it because
   setpgid or setpgrp might not exist on a system without job control.
   It might be considered misplaced (on the other hand, process groups and
   job control are closely related to ttys).

   For a more clean implementation, in libiberty, put a setpgid which merely
   calls setpgrp and a setpgrp which does nothing (any system with job control
   will have one or the other).  */
int
gdb_setpgid (void)
{
  int retval = 0;

  if (job_control)
    {
#if defined (HAVE_TERMIOS) || defined (TIOCGPGRP)
#ifdef HAVE_SETPGID
      /* The call setpgid (0, 0) is supposed to work and mean the same
         thing as this, but on Ultrix 4.2A it fails with EPERM (and
         setpgid (getpid (), getpid ()) succeeds).  */
      retval = setpgid (getpid (), getpid ());
#else
#ifdef HAVE_SETPGRP
#ifdef SETPGRP_VOID 
      retval = setpgrp ();
#else
      retval = setpgrp (getpid (), getpid ());
#endif
#endif /* HAVE_SETPGRP */
#endif /* HAVE_SETPGID */
#endif /* defined (HAVE_TERMIOS) || defined (TIOCGPGRP) */
    }

  return retval;
}

/* Get all the current tty settings (including whether we have a
   tty at all!).  We can't do this in _initialize_inflow because
   serial_fdopen() won't work until the serial_ops_list is
   initialized, but we don't want to do it lazily either, so
   that we can guarantee stdin_serial is opened if there is
   a terminal.  */
void
initialize_stdin_serial (void)
{
  stdin_serial = serial_fdopen (0);
}

void
_initialize_inflow (void)
{
  add_info ("terminal", term_info,
	    _("Print inferior's saved terminal status."));

  add_com ("kill", class_run, kill_command,
	   _("Kill execution of program being debugged."));

  inferior_ptid = null_ptid;

  terminal_is_ours = 1;

  /* OK, figure out whether we have job control.  If neither termios nor
     sgtty (i.e. termio or go32), leave job_control 0.  */

#if defined (HAVE_TERMIOS)
  /* Do all systems with termios have the POSIX way of identifying job
     control?  I hope so.  */
#ifdef _POSIX_JOB_CONTROL
  job_control = 1;
#else
#ifdef _SC_JOB_CONTROL
  job_control = sysconf (_SC_JOB_CONTROL);
#else
  job_control = 0;		/* have to assume the worst */
#endif /* _SC_JOB_CONTROL */
#endif /* _POSIX_JOB_CONTROL */
#endif /* HAVE_TERMIOS */

#ifdef HAVE_SGTTY
#ifdef TIOCGPGRP
  job_control = 1;
#else
  job_control = 0;
#endif /* TIOCGPGRP */
#endif /* sgtty */
}