1 /* Low level interface to ptrace, for GDB when running under Unix.
2 Copyright 1986, 1987, 1989, 1991, 1992 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
33 #if !defined (HAVE_TERMIOS) && !defined (HAVE_TERMIO) && !defined (HAVE_SGTTY) && !defined (__GO32__)
37 #if defined (HAVE_TERMIOS)
43 #define PROCESS_GROUP_TYPE pid_t
48 /* This is only used for the ultra. Does it have pid_t? */
49 #define PROCESS_GROUP_TYPE short
51 #define PROCESS_GROUP_TYPE int
56 kill_command
PARAMS ((char *, int));
59 terminal_ours_1
PARAMS ((int));
61 /* Nonzero if we have job control. */
65 /* Nonzero if we are debugging an attached outside process
66 rather than an inferior. */
71 /* Record terminal status separately for debugger and inferior. */
73 static serial_t stdin_serial
;
75 /* TTY state for the inferior. We save it whenever the inferior stops, and
76 restore it when it resumes. */
77 static serial_ttystate inferior_ttystate
;
79 /* Our own tty state, which we restore every time we need to deal with the
80 terminal. We only set it once, when GDB first starts. The settings of
81 flags which readline saves and restores and unimportant. */
82 static serial_ttystate our_ttystate
;
84 /* fcntl flags for us and the inferior. Saved and restored just like
85 {our,inferior}_ttystate. */
86 static int tflags_inferior
;
87 static int tflags_ours
;
89 #ifdef PROCESS_GROUP_TYPE
90 /* Process group for us and the inferior. Saved and restored just like
91 {our,inferior}_ttystate. */
92 PROCESS_GROUP_TYPE our_process_group
;
93 PROCESS_GROUP_TYPE inferior_process_group
;
96 /* While the inferior is running, we want SIGINT and SIGQUIT to go to the
97 inferior only. If we have job control, that takes care of it. If not,
98 we save our handlers in these two variables and set SIGINT and SIGQUIT
100 static void (*sigint_ours
) ();
101 static void (*sigquit_ours
) ();
103 /* The name of the tty (from the `tty' command) that we gave to the inferior
104 when it was last started. */
106 static char *inferior_thisrun_terminal
;
108 /* Nonzero if our terminal settings are in effect. Zero if the
109 inferior's settings are in effect. Ignored if !gdb_has_a_terminal
112 static int terminal_is_ours
;
114 enum {yes
, no
, have_not_checked
} gdb_has_a_terminal_flag
= have_not_checked
;
116 /* Does GDB have a terminal (on stdin)? */
118 gdb_has_a_terminal ()
120 switch (gdb_has_a_terminal_flag
)
126 case have_not_checked
:
127 /* Get all the current tty settings (including whether we have a tty at
128 all!). Can't do this in _initialize_inflow because SERIAL_FDOPEN
129 won't work until the serial_ops_list is initialized. */
132 tflags_ours
= fcntl (0, F_GETFL
, 0);
135 gdb_has_a_terminal_flag
= no
;
136 stdin_serial
= SERIAL_FDOPEN (0);
137 if (stdin_serial
!= NULL
)
139 our_ttystate
= SERIAL_GET_TTY_STATE (stdin_serial
);
141 if (our_ttystate
!= NULL
)
143 gdb_has_a_terminal_flag
= yes
;
145 our_process_group
= tcgetpgrp (0);
148 ioctl (0, TIOCGPGRP
, &our_process_group
);
153 return gdb_has_a_terminal_flag
== yes
;
155 /* "Can't happen". */
160 /* Macro for printing errors from ioctl operations */
162 #define OOPSY(what) \
164 fprintf_unfiltered(gdb_stderr, "[%s failed in terminal_inferior: %s]\n", \
165 what, strerror (errno))
167 static void terminal_ours_1
PARAMS ((int));
169 /* Initialize the terminal settings we record for the inferior,
170 before we actually run the inferior. */
173 terminal_init_inferior ()
175 if (gdb_has_a_terminal ())
177 /* We could just as well copy our_ttystate (if we felt like adding
178 a new function SERIAL_COPY_TTY_STATE). */
179 if (inferior_ttystate
)
180 free (inferior_ttystate
);
181 inferior_ttystate
= SERIAL_GET_TTY_STATE (stdin_serial
);
182 #ifdef PROCESS_GROUP_TYPE
184 /* This is for Lynx, and should be cleaned up by having Lynx be
185 a separate debugging target with a version of
186 target_terminal_init_inferior which passes in the process
187 group to a generic routine which does all the work (and the
188 non-threaded child_terminal_init_inferior can just pass in
189 inferior_pid to the same routine). */
190 inferior_process_group
= PIDGET (inferior_pid
);
192 inferior_process_group
= inferior_pid
;
196 /* Make sure that next time we call terminal_inferior (which will be
197 before the program runs, as it needs to be), we install the new
199 terminal_is_ours
= 1;
203 /* Put the inferior's terminal settings into effect.
204 This is preparation for starting or resuming the inferior. */
209 if (gdb_has_a_terminal () && terminal_is_ours
210 && inferior_thisrun_terminal
== 0)
215 /* Is there a reason this is being done twice? It happens both
216 places we use F_SETFL, so I'm inclined to think perhaps there
217 is some reason, however perverse. Perhaps not though... */
218 result
= fcntl (0, F_SETFL
, tflags_inferior
);
219 result
= fcntl (0, F_SETFL
, tflags_inferior
);
220 OOPSY ("fcntl F_SETFL");
223 /* Because we were careful to not change in or out of raw mode in
224 terminal_ours, we will not change in our out of raw mode with
225 this call, so we don't flush any input. */
226 result
= SERIAL_SET_TTY_STATE (stdin_serial
, inferior_ttystate
);
227 OOPSY ("setting tty state");
231 sigint_ours
= (void (*) ()) signal (SIGINT
, SIG_IGN
);
232 sigquit_ours
= (void (*) ()) signal (SIGQUIT
, SIG_IGN
);
235 /* If attach_flag is set, we don't know whether we are sharing a
236 terminal with the inferior or not. (attaching a process
237 without a terminal is one case where we do not; attaching a
238 process which we ran from the same shell as GDB via `&' is
239 one case where we do, I think (but perhaps this is not
240 `sharing' in the sense that we need to save and restore tty
241 state)). I don't know if there is any way to tell whether we
242 are sharing a terminal. So what we do is to go through all
243 the saving and restoring of the tty state, but ignore errors
244 setting the process group, which will happen if we are not
245 sharing a terminal). */
250 result
= tcsetpgrp (0, inferior_process_group
);
256 result
= ioctl (0, TIOCSPGRP
, &inferior_process_group
);
263 terminal_is_ours
= 0;
266 /* Put some of our terminal settings into effect,
267 enough to get proper results from our output,
268 but do not change into or out of RAW mode
269 so that no input is discarded.
271 After doing this, either terminal_ours or terminal_inferior
272 should be called to get back to a normal state of affairs. */
275 terminal_ours_for_output ()
280 /* Put our terminal settings into effect.
281 First record the inferior's terminal settings
282 so they can be restored properly later. */
290 /* output_only is not used, and should not be used unless we introduce
291 separate terminal_is_ours and terminal_is_ours_for_output
295 terminal_ours_1 (output_only
)
298 /* Checking inferior_thisrun_terminal is necessary so that
299 if GDB is running in the background, it won't block trying
300 to do the ioctl()'s below. Checking gdb_has_a_terminal
301 avoids attempting all the ioctl's when running in batch. */
302 if (inferior_thisrun_terminal
!= 0 || gdb_has_a_terminal () == 0)
305 if (!terminal_is_ours
)
307 /* Ignore this signal since it will happen when we try to set the
312 terminal_is_ours
= 1;
316 osigttou
= (void (*) ()) signal (SIGTTOU
, SIG_IGN
);
319 if (inferior_ttystate
)
320 free (inferior_ttystate
);
321 inferior_ttystate
= SERIAL_GET_TTY_STATE (stdin_serial
);
323 inferior_process_group
= tcgetpgrp (0);
326 ioctl (0, TIOCGPGRP
, &inferior_process_group
);
329 /* Here we used to set ICANON in our ttystate, but I believe this
330 was an artifact from before when we used readline. Readline sets
331 the tty state when it needs to.
332 FIXME-maybe: However, query() expects non-raw mode and doesn't
333 use readline. Maybe query should use readline (on the other hand,
334 this only matters for HAVE_SGTTY, not termio or termios, I think). */
336 /* Set tty state to our_ttystate. We don't change in our out of raw
337 mode, to avoid flushing input. We need to do the same thing
338 regardless of output_only, because we don't have separate
339 terminal_is_ours and terminal_is_ours_for_output flags. It's OK,
340 though, since readline will deal with raw mode when/if it needs to.
343 SERIAL_NOFLUSH_SET_TTY_STATE (stdin_serial
, our_ttystate
,
349 result
= tcsetpgrp (0, our_process_group
);
351 /* This fails on Ultrix with EINVAL if you run the testsuite
352 in the background with nohup, and then log out. GDB never
353 used to check for an error here, so perhaps there are other
354 such situations as well. */
356 fprintf_unfiltered (gdb_stderr
, "[tcsetpgrp failed in terminal_ours: %s]\n",
362 result
= ioctl (0, TIOCSPGRP
, &our_process_group
);
368 signal (SIGTTOU
, osigttou
);
373 signal (SIGINT
, sigint_ours
);
374 signal (SIGQUIT
, sigquit_ours
);
378 tflags_inferior
= fcntl (0, F_GETFL
, 0);
380 /* Is there a reason this is being done twice? It happens both
381 places we use F_SETFL, so I'm inclined to think perhaps there
382 is some reason, however perverse. Perhaps not though... */
383 result
= fcntl (0, F_SETFL
, tflags_ours
);
384 result
= fcntl (0, F_SETFL
, tflags_ours
);
387 result
= result
; /* lint */
393 term_info (arg
, from_tty
)
397 target_terminal_info (arg
, from_tty
);
402 child_terminal_info (args
, from_tty
)
406 if (!gdb_has_a_terminal ())
408 printf_filtered ("This GDB does not control a terminal.\n");
412 printf_filtered ("Inferior's terminal status (currently saved by GDB):\n");
414 /* First the fcntl flags. */
418 flags
= tflags_inferior
;
420 printf_filtered ("File descriptor flags = ");
423 #define O_ACCMODE (O_RDONLY | O_WRONLY | O_RDWR)
425 /* (O_ACCMODE) parens are to avoid Ultrix header file bug */
426 switch (flags
& (O_ACCMODE
))
428 case O_RDONLY
: printf_filtered ("O_RDONLY"); break;
429 case O_WRONLY
: printf_filtered ("O_WRONLY"); break;
430 case O_RDWR
: printf_filtered ("O_RDWR"); break;
432 flags
&= ~(O_ACCMODE
);
435 if (flags
& O_NONBLOCK
)
436 printf_filtered (" | O_NONBLOCK");
437 flags
&= ~O_NONBLOCK
;
440 #if defined (O_NDELAY)
441 /* If O_NDELAY and O_NONBLOCK are defined to the same thing, we will
442 print it as O_NONBLOCK, which is good cause that is what POSIX
443 has, and the flag will already be cleared by the time we get here. */
444 if (flags
& O_NDELAY
)
445 printf_filtered (" | O_NDELAY");
449 if (flags
& O_APPEND
)
450 printf_filtered (" | O_APPEND");
453 #if defined (O_BINARY)
454 if (flags
& O_BINARY
)
455 printf_filtered (" | O_BINARY");
460 printf_filtered (" | 0x%x", flags
);
461 printf_filtered ("\n");
464 #ifdef PROCESS_GROUP_TYPE
465 printf_filtered ("Process group = %d\n", inferior_process_group
);
468 SERIAL_PRINT_TTY_STATE (stdin_serial
, inferior_ttystate
);
471 /* NEW_TTY_PREFORK is called before forking a new child process,
472 so we can record the state of ttys in the child to be formed.
473 TTYNAME is null if we are to share the terminal with gdb;
474 or points to a string containing the name of the desired tty.
476 NEW_TTY is called in new child processes under Unix, which will
477 become debugger target processes. This actually switches to
478 the terminal specified in the NEW_TTY_PREFORK call. */
481 new_tty_prefork (ttyname
)
484 /* Save the name for later, for determining whether we and the child
485 are sharing a tty. */
486 inferior_thisrun_terminal
= ttyname
;
494 if (inferior_thisrun_terminal
== 0)
496 #if !defined(__GO32__)
498 /* Disconnect the child process from our controlling terminal. On some
499 systems (SVR4 for example), this may cause a SIGTTOU, so temporarily
501 tty
= open("/dev/tty", O_RDWR
);
506 osigttou
= (void (*)()) signal(SIGTTOU
, SIG_IGN
);
507 ioctl(tty
, TIOCNOTTY
, 0);
509 signal(SIGTTOU
, osigttou
);
513 /* Now open the specified new terminal. */
516 tty
= open(inferior_thisrun_terminal
, O_RDWR
| O_NOCTTY
);
518 tty
= open(inferior_thisrun_terminal
, O_RDWR
);
522 print_sys_errmsg (inferior_thisrun_terminal
, errno
);
526 /* Avoid use of dup2; doesn't exist on all systems. */
528 { close (0); dup (tty
); }
530 { close (1); dup (tty
); }
532 { close (2); dup (tty
); }
538 /* Kill the inferior process. Make us have no inferior. */
542 kill_command (arg
, from_tty
)
546 /* Shouldn't this be target_has_execution? FIXME. */
547 if (inferior_pid
== 0)
548 error ("The program is not being run.");
549 if (!query ("Kill the program being debugged? "))
550 error ("Not confirmed.");
553 init_thread_list(); /* Destroy thread info */
555 /* Killing off the inferior can leave us with a core file. If so,
556 print the state we are left in. */
557 if (target_has_stack
) {
558 printf_filtered ("In %s,\n", current_target
->to_longname
);
559 if (selected_frame
== NULL
)
560 fputs_filtered ("No selected stack frame.\n", gdb_stdout
);
562 print_stack_frame (selected_frame
, selected_frame_level
, 1);
566 /* The inferior process has died. Long live the inferior! */
569 generic_mourn_inferior ()
573 breakpoint_init_inferior ();
574 registers_changed ();
576 #ifdef CLEAR_DEFERRED_STORES
577 /* Delete any pending stores to the inferior... */
578 CLEAR_DEFERRED_STORES
;
582 reinit_frame_cache ();
584 /* It is confusing to the user for ignore counts to stick around
585 from previous runs of the inferior. So clear them. */
586 breakpoint_clear_ignore_counts ();
589 /* Call set_sigint_trap when you need to pass a signal on to an attached
590 process when handling SIGINT */
597 kill (inferior_pid
, SIGINT
);
600 static void (*osig
)();
605 osig
= (void (*) ()) signal (SIGINT
, pass_signal
);
611 signal (SIGINT
, osig
);
615 /* This is here because this is where we figure out whether we (probably)
616 have job control. Just using job_control only does part of it because
617 setpgid or setpgrp might not exist on a system without job control.
618 It might be considered misplaced (on the other hand, process groups and
619 job control are closely related to ttys).
621 For a more clean implementation, in libiberty, put a setpgid which merely
622 calls setpgrp and a setpgrp which does nothing (any system with job control
623 will have one or the other). */
631 #if defined (NEED_POSIX_SETPGID) || defined (HAVE_TERMIOS)
632 /* Do all systems with termios have setpgid? I hope so. */
633 /* setpgid (0, 0) is supposed to work and mean the same thing as
634 this, but on Ultrix 4.2A it fails with EPERM (and
635 setpgid (getpid (), getpid ()) succeeds). */
636 retval
= setpgid (getpid (), getpid ());
638 #if defined (TIOCGPGRP)
639 #if defined(USG) && !defined(SETPGRP_ARGS)
642 retval
= setpgrp (getpid (), getpid ());
644 #endif /* TIOCGPGRP. */
645 #endif /* NEED_POSIX_SETPGID */
651 _initialize_inflow ()
653 add_info ("terminal", term_info
,
654 "Print inferior's saved terminal status.");
656 add_com ("kill", class_run
, kill_command
,
657 "Kill execution of program being debugged.");
661 terminal_is_ours
= 1;
663 /* OK, figure out whether we have job control. If neither termios nor
664 sgtty (i.e. termio or go32), leave job_control 0. */
666 #if defined (HAVE_TERMIOS)
667 /* Do all systems with termios have the POSIX way of identifying job
668 control? I hope so. */
669 #ifdef _POSIX_JOB_CONTROL
672 job_control
= sysconf (_SC_JOB_CONTROL
);
681 #endif /* TIOCGPGRP */