/* Low level interface to ptrace, for GDB when running under Unix.
- Copyright 1986, 1987, 1989, 1991, 1992 Free Software Foundation, Inc.
+ Copyright (C) 1986-2019 Free Software Foundation, Inc.
-This file is part of GDB.
+ 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 2 of the License, or
-(at your option) any later version.
+ 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.
+ 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, write to the Free Software
-Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+ 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 "signals.h"
+#include "serial.h"
#include "terminal.h"
#include "target.h"
-
-#ifdef USG
-#include <sys/types.h>
-#endif
-
-/* Some USG-esque systems (some of which are BSD-esque enough so that USG
- is not defined) want this header, and it won't do any harm. */
-#include <fcntl.h>
-
-#include <sys/param.h>
+#include "gdbthread.h"
+#include "observable.h"
#include <signal.h>
+#include <fcntl.h>
+#include "gdb_select.h"
-static void
-kill_command PARAMS ((char *, int));
-
-static void
-terminal_ours_1 PARAMS ((int));
+#include "inflow.h"
+#include "gdbcmd.h"
+#ifdef HAVE_TERMIOS_H
+#include <termios.h>
+#endif
+#include "gdbsupport/job-control.h"
-extern struct target_ops child_ops;
+#ifdef HAVE_SYS_IOCTL_H
+#include <sys/ioctl.h>
+#endif
-/* Nonzero if we are debugging an attached outside process
- rather than an inferior. */
+#ifndef O_NOCTTY
+#define O_NOCTTY 0
+#endif
-int attach_flag;
+static void pass_signal (int);
+static void child_terminal_ours_1 (target_terminal_state);
\f
/* Record terminal status separately for debugger and inferior. */
-/* Does GDB have a terminal (on stdin)? */
-int gdb_has_a_terminal;
-#if !defined(__GO32__)
-static TERMINAL sg_inferior;
-static TERMINAL sg_ours;
-#endif
-static int tflags_inferior;
-static int tflags_ours;
-
-#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN)
-static struct tchars tc_inferior;
-static struct tchars tc_ours;
-#endif
+static struct serial *stdin_serial;
-#if defined(TIOCGLTC) && !defined(TIOCGLTC_BROKEN)
-static struct ltchars ltc_inferior;
-static struct ltchars ltc_ours;
-#endif
-
-#ifdef TIOCLGET
-static int lmode_inferior;
-static int lmode_ours;
-#endif
+/* Terminal related info we need to keep track of. Each inferior
+ holds an instance of this structure --- we save it whenever the
+ corresponding inferior stops, and restore it to the terminal when
+ the inferior is resumed in the foreground. */
+struct terminal_info
+{
+ terminal_info () = default;
+ ~terminal_info ();
+
+ terminal_info &operator= (const terminal_info &) = default;
+
+ /* The name of the tty (from the `tty' command) that we gave to the
+ inferior when it was started. */
+ char *run_terminal = nullptr;
+
+ /* TTY state. We save it whenever the inferior stops, and restore
+ it when it resumes in the foreground. */
+ serial_ttystate ttystate {};
+
+#ifdef HAVE_TERMIOS_H
+ /* The terminal's foreground process group. Saved whenever the
+ inferior stops. This is the pgrp displayed by "info terminal".
+ Note that this may be not the inferior's actual process group,
+ since each inferior that we spawn has its own process group, and
+ only one can be in the foreground at a time. When the inferior
+ resumes, if we can determine the inferior's actual pgrp, then we
+ make that the foreground pgrp instead of what was saved here.
+ While it's a bit arbitrary which inferior's pgrp ends up in the
+ foreground when we resume several inferiors, this at least makes
+ 'resume inf1+inf2' + 'stop all' + 'resume inf2' end up with
+ inf2's pgrp in the foreground instead of inf1's (which would be
+ problematic since it would be left stopped: Ctrl-C wouldn't work,
+ for example). */
+ pid_t process_group = 0;
+#endif
+
+ /* fcntl flags. Saved and restored just like ttystate. */
+ int tflags = 0;
+};
+
+/* Our own tty state, which we restore every time we need to deal with
+ the terminal. This is set once, when GDB first starts, and then
+ whenever we enter/leave TUI mode (gdb_save_tty_state). The
+ settings of flags which readline saves and restores are
+ unimportant. */
+static struct terminal_info our_terminal_info;
+
+/* Snapshot of the initial tty state taken during initialization of
+ GDB, before readline/ncurses have had a chance to change it. This
+ is used as the initial tty state given to each new spawned
+ inferior. Unlike our_terminal_info, this is only ever set
+ once. */
+static serial_ttystate initial_gdb_ttystate;
+
+static struct terminal_info *get_inflow_inferior_data (struct inferior *);
+
+/* 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 sighandler_t sigint_ours;
+#ifdef SIGQUIT
+static sighandler_t sigquit_ours;
+#endif
+
+/* The name of the tty (from the `tty' command) that we're giving to
+ the inferior when starting it up. This is only (and should only
+ be) used as a transient global by new_tty_prefork,
+ create_tty_session, new_tty and new_tty_postfork, all called from
+ fork_inferior, while forking a new child. */
+static const char *inferior_thisrun_terminal;
+
+/* Track who owns GDB's terminal (is it GDB or some inferior?). While
+ target_terminal::is_ours() etc. tracks the core's intention and is
+ independent of the target backend, this tracks the actual state of
+ GDB's own tty. So for example,
+
+ (target_terminal::is_inferior () && gdb_tty_state == terminal_is_ours)
+
+ is true when the (native) inferior is not sharing a terminal with
+ GDB (e.g., because we attached to an inferior that is running on a
+ different terminal). */
+static target_terminal_state gdb_tty_state = target_terminal_state::is_ours;
+
+/* See terminal.h. */
-#ifdef TIOCGPGRP
-# ifdef SHORT_PGRP
-static short pgrp_inferior;
-static short pgrp_ours;
-# else /* not def SHORT_PGRP */
-static int pgrp_inferior;
-static int pgrp_ours;
-# endif /* not def SHORT_PGRP */
-#else /* not def TIOCGPGRP */
-static void (*sigint_ours) ();
-static void (*sigquit_ours) ();
-#endif /* TIOCGPGRP */
+void
+set_initial_gdb_ttystate (void)
+{
+ /* Note we can't do any of this in _initialize_inflow because at
+ that point stdin_serial has not been created yet. */
-/* The name of the tty (from the `tty' command) that we gave to the inferior
- when it was last started. */
+ initial_gdb_ttystate = serial_get_tty_state (stdin_serial);
-static char *inferior_thisrun_terminal;
+ if (initial_gdb_ttystate != NULL)
+ {
+ our_terminal_info.ttystate
+ = serial_copy_tty_state (stdin_serial, initial_gdb_ttystate);
+#ifdef F_GETFL
+ our_terminal_info.tflags = fcntl (0, F_GETFL, 0);
+#endif
+#ifdef HAVE_TERMIOS_H
+ our_terminal_info.process_group = tcgetpgrp (0);
+#endif
+ }
+}
-/* Nonzero if our terminal settings are in effect.
- Zero if the inferior's settings are in effect. */
+/* Does GDB have a terminal (on stdin)? */
-static int terminal_is_ours;
+static int
+gdb_has_a_terminal (void)
+{
+ return initial_gdb_ttystate != NULL;
+}
/* Macro for printing errors from ioctl operations */
#define OOPSY(what) \
if (result == -1) \
- fprintf(stderr, "[%s failed in terminal_inferior: %s]\n", \
- what, strerror (errno))
-
-static void terminal_ours_1 ();
+ fprintf_unfiltered(gdb_stderr, "[%s failed in terminal_inferior: %s]\n", \
+ what, safe_strerror (errno))
/* Initialize the terminal settings we record for the inferior,
before we actually run the inferior. */
void
-terminal_init_inferior ()
+child_terminal_init (struct target_ops *self)
{
-#if !defined(__GO32__)
- sg_inferior = sg_ours;
- tflags_inferior = tflags_ours;
+ if (!gdb_has_a_terminal ())
+ return;
-#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN)
- tc_inferior = tc_ours;
-#endif
+ inferior *inf = current_inferior ();
+ terminal_info *tinfo = get_inflow_inferior_data (inf);
-#if defined(TIOCGLTC) && !defined(TIOCGLTC_BROKEN)
- ltc_inferior = ltc_ours;
+#ifdef HAVE_TERMIOS_H
+ /* A child we spawn should be a process group leader (PGID==PID) at
+ this point, though that may not be true if we're attaching to an
+ existing process. */
+ tinfo->process_group = inf->pid;
#endif
-#ifdef TIOCLGET
- lmode_inferior = lmode_ours;
-#endif
+ xfree (tinfo->ttystate);
+ tinfo->ttystate = serial_copy_tty_state (stdin_serial, initial_gdb_ttystate);
+}
+
+/* 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
+gdb_save_tty_state (void)
+{
+ if (gdb_has_a_terminal ())
+ {
+ xfree (our_terminal_info.ttystate);
+ our_terminal_info.ttystate = serial_get_tty_state (stdin_serial);
+ }
+}
+
+/* Try to determine whether TTY is GDB's input terminal. Returns
+ TRIBOOL_UNKNOWN if we can't tell. */
+
+static tribool
+is_gdb_terminal (const char *tty)
+{
+ struct stat gdb_tty;
+ struct stat other_tty;
+ int res;
+
+ res = stat (tty, &other_tty);
+ if (res == -1)
+ return TRIBOOL_UNKNOWN;
+
+ res = fstat (STDIN_FILENO, &gdb_tty);
+ if (res == -1)
+ return TRIBOOL_UNKNOWN;
+
+ return ((gdb_tty.st_dev == other_tty.st_dev
+ && gdb_tty.st_ino == other_tty.st_ino)
+ ? TRIBOOL_TRUE
+ : TRIBOOL_FALSE);
+}
-#ifdef TIOCGPGRP
- pgrp_inferior = inferior_pid;
-#endif /* TIOCGPGRP */
+/* Helper for sharing_input_terminal. Try to determine whether
+ inferior INF is using the same TTY for input as GDB is. Returns
+ TRIBOOL_UNKNOWN if we can't tell. */
+
+static tribool
+sharing_input_terminal_1 (inferior *inf)
+{
+ /* Using host-dependent code here is fine, because the
+ child_terminal_foo functions are meant to be used by child/native
+ targets. */
+#if defined (__linux__) || defined (__sun__)
+ char buf[100];
+
+ xsnprintf (buf, sizeof (buf), "/proc/%d/fd/0", inf->pid);
+ return is_gdb_terminal (buf);
+#else
+ return TRIBOOL_UNKNOWN;
#endif
- terminal_is_ours = 1;
}
-/* Put the inferior's terminal settings into effect.
- This is preparation for starting or resuming the inferior. */
+/* Return true if the inferior is using the same TTY for input as GDB
+ is. If this is true, then we save/restore terminal flags/state.
+
+ This is necessary because if inf->attach_flag is set, we don't
+ offhand 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.
+
+ If we can't determine, we assume the TTY is being shared. This
+ works OK if you're only debugging one inferior. However, if you're
+ debugging more than one inferior, and e.g., one is spawned by GDB
+ with "run" (sharing terminal with GDB), and another is attached to
+ (and running on a different terminal, as is most common), then it
+ matters, because we can only restore the terminal settings of one
+ of the inferiors, and in that scenario, we want to restore the
+ settings of the "run"'ed inferior.
+
+ Note, this is not the same as determining whether GDB and the
+ inferior are in the same session / connected to the same
+ controlling tty. An inferior (fork child) may call setsid,
+ disconnecting itself from the ctty, while still leaving
+ stdin/stdout/stderr associated with the original terminal. If
+ we're debugging that process, we should also save/restore terminal
+ settings. */
+
+static bool
+sharing_input_terminal (inferior *inf)
+{
+ terminal_info *tinfo = get_inflow_inferior_data (inf);
+
+ tribool res = sharing_input_terminal_1 (inf);
+
+ if (res == TRIBOOL_UNKNOWN)
+ {
+ /* As fallback, if we can't determine by stat'ing the inferior's
+ tty directly (because it's not supported on this host) and
+ the child was spawned, check whether run_terminal is our tty.
+ This isn't ideal, since this is checking the child's
+ controlling terminal, not the input terminal (which may have
+ been redirected), but is still better than nothing. A false
+ positive ("set inferior-tty" points to our terminal, but I/O
+ was redirected) is much more likely than a false negative
+ ("set inferior-tty" points to some other terminal, and then
+ output was redirected to our terminal), and with a false
+ positive we just end up trying to save/restore terminal
+ settings when we didn't need to or we actually can't. */
+ if (tinfo->run_terminal != NULL)
+ res = is_gdb_terminal (tinfo->run_terminal);
+
+ /* If we still can't determine, assume yes. */
+ if (res == TRIBOOL_UNKNOWN)
+ return true;
+ }
+
+ return res == TRIBOOL_TRUE;
+}
+
+/* Put the inferior's terminal settings into effect. This is
+ preparation for starting or resuming the inferior. */
void
-terminal_inferior ()
+child_terminal_inferior (struct target_ops *self)
{
-#if !defined(__GO32__)
- int result;
+ /* If we resume more than one inferior in the foreground on GDB's
+ terminal, then the first inferior's terminal settings "win".
+ Note that every child process is put in its own process group, so
+ the first process that ends up resumed ends up determining which
+ process group the kernel forwards Ctrl-C/Ctrl-Z (SIGINT/SIGTTOU)
+ to. */
+ if (gdb_tty_state == target_terminal_state::is_inferior)
+ return;
- if (gdb_has_a_terminal && terminal_is_ours && inferior_thisrun_terminal == 0)
+ inferior *inf = current_inferior ();
+ terminal_info *tinfo = get_inflow_inferior_data (inf);
+
+ if (gdb_has_a_terminal ()
+ && tinfo->ttystate != NULL
+ && sharing_input_terminal (inf))
{
- result = fcntl (0, F_SETFL, tflags_inferior);
- result = fcntl (0, F_SETFL, tflags_inferior);
+ int result;
+
+ /* Ignore SIGTTOU since it will happen when we try to set the
+ terminal's state (if gdb_tty_state is currently
+ ours_for_output). */
+ scoped_ignore_sigttou ignore_sigttou;
+
+#ifdef F_GETFL
+ result = fcntl (0, F_SETFL, tinfo->tflags);
OOPSY ("fcntl F_SETFL");
- result = ioctl (0, TIOCSETN, &sg_inferior);
- OOPSY ("ioctl TIOCSETN");
+#endif
+
+ result = serial_set_tty_state (stdin_serial, tinfo->ttystate);
+ OOPSY ("setting tty state");
-#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN)
- result = ioctl (0, TIOCSETC, &tc_inferior);
- OOPSY ("ioctl TIOCSETC");
+ if (!job_control)
+ {
+ sigint_ours = signal (SIGINT, SIG_IGN);
+#ifdef SIGQUIT
+ sigquit_ours = signal (SIGQUIT, SIG_IGN);
#endif
-#if defined(TIOCGLTC) && !defined(TIOCGLTC_BROKEN)
- result = ioctl (0, TIOCSLTC, <c_inferior);
- OOPSY ("ioctl TIOCSLTC");
+ }
+
+ if (job_control)
+ {
+#ifdef HAVE_TERMIOS_H
+ /* If we can't tell the inferior's actual process group,
+ then restore whatever was the foreground pgrp the last
+ time the inferior was running. See also comments
+ describing terminal_state::process_group. */
+#ifdef HAVE_GETPGID
+ result = tcsetpgrp (0, getpgid (inf->pid));
+#else
+ result = tcsetpgrp (0, tinfo->process_group);
#endif
-#ifdef TIOCLGET
- result = ioctl (0, TIOCLSET, &lmode_inferior);
- OOPSY ("ioctl TIOCLSET");
+ if (result == -1)
+ {
+#if 0
+ /* This fails if either GDB has no controlling terminal,
+ e.g., running under 'setsid(1)', or if the inferior
+ is not attached to GDB's controlling terminal. E.g.,
+ if it called setsid to create a new session or used
+ the TIOCNOTTY ioctl, or simply if we've attached to a
+ process running on another terminal and we couldn't
+ tell whether it was sharing GDB's terminal (and so
+ assumed yes). */
+ fprintf_unfiltered
+ (gdb_stderr,
+ "[tcsetpgrp failed in child_terminal_inferior: %s]\n",
+ safe_strerror (errno));
+#endif
+ }
#endif
+ }
-#ifdef TIOCGPGRP
- result = ioctl (0, TIOCSPGRP, &pgrp_inferior);
- /* If we attached to the process, we might or might not be sharing
- a terminal. Avoid printing error msg if we are unable to set our
- terminal's process group to his process group ID. */
- if (!attach_flag) {
- OOPSY ("ioctl TIOCSPGRP");
- }
-#else
- sigint_ours = (void (*) ()) signal (SIGINT, SIG_IGN);
- sigquit_ours = (void (*) ()) signal (SIGQUIT, SIG_IGN);
-#endif /* TIOCGPGRP */
+ gdb_tty_state = target_terminal_state::is_inferior;
}
-#endif
- terminal_is_ours = 0;
}
/* Put some of our terminal settings into effect,
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. */
+ should be called to get back to a normal state of affairs.
+
+ N.B. The implementation is (currently) no different than
+ child_terminal_ours. See child_terminal_ours_1. */
void
-terminal_ours_for_output ()
+child_terminal_ours_for_output (struct target_ops *self)
{
- terminal_ours_1 (1);
+ child_terminal_ours_1 (target_terminal_state::is_ours_for_output);
}
/* Put our terminal settings into effect.
First record the inferior's terminal settings
- so they can be restored properly later. */
+ so they can be restored properly later.
+
+ N.B. Targets that want to use this with async support must build that
+ support on top of this (e.g., the caller still needs to add stdin to the
+ event loop). E.g., see linux_nat_terminal_ours. */
void
-terminal_ours ()
+child_terminal_ours (struct target_ops *self)
{
- terminal_ours_1 (0);
+ child_terminal_ours_1 (target_terminal_state::is_ours);
}
+/* Save the current terminal settings in the inferior's terminal_info
+ cache. */
+
+void
+child_terminal_save_inferior (struct target_ops *self)
+{
+ /* Avoid attempting all the ioctl's when running in batch. */
+ if (!gdb_has_a_terminal ())
+ return;
+
+ inferior *inf = current_inferior ();
+ terminal_info *tinfo = get_inflow_inferior_data (inf);
+
+ /* No need to save/restore if the inferior is not sharing GDB's
+ tty. */
+ if (!sharing_input_terminal (inf))
+ return;
+
+ xfree (tinfo->ttystate);
+ tinfo->ttystate = serial_get_tty_state (stdin_serial);
+
+#ifdef HAVE_TERMIOS_H
+ tinfo->process_group = tcgetpgrp (0);
+#endif
+
+#ifdef F_GETFL
+ tinfo->tflags = fcntl (0, F_GETFL, 0);
+#endif
+}
+
+/* Switch terminal state to DESIRED_STATE, either is_ours, or
+ is_ours_for_output. */
+
static void
-terminal_ours_1 (output_only)
- int output_only;
-{
-#if !defined(__GO32__)
- int result;
-#ifdef TIOCGPGRP
- /* Ignore this signal since it will happen when we try to set the pgrp. */
- void (*osigttou) ();
-#endif /* TIOCGPGRP */
-
- /* 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)
+child_terminal_ours_1 (target_terminal_state desired_state)
+{
+ gdb_assert (desired_state != target_terminal_state::is_inferior);
+
+ /* Avoid attempting all the ioctl's when running in batch. */
+ if (!gdb_has_a_terminal ())
return;
- if (!terminal_is_ours)
+ if (gdb_tty_state != desired_state)
{
- terminal_is_ours = 1;
+ int result ATTRIBUTE_UNUSED;
-#ifdef TIOCGPGRP
- osigttou = (void (*) ()) signal (SIGTTOU, SIG_IGN);
+ /* Ignore SIGTTOU since it will happen when we try to set the
+ terminal's pgrp. */
+ scoped_ignore_sigttou ignore_sigttou;
- result = ioctl (0, TIOCGPGRP, &pgrp_inferior);
- result = ioctl (0, TIOCSPGRP, &pgrp_ours);
+ /* Set tty state to our_ttystate. */
+ serial_set_tty_state (stdin_serial, our_terminal_info.ttystate);
- signal (SIGTTOU, osigttou);
-#else
- signal (SIGINT, sigint_ours);
- signal (SIGQUIT, sigquit_ours);
-#endif /* TIOCGPGRP */
-
- tflags_inferior = fcntl (0, F_GETFL, 0);
- result = ioctl (0, TIOCGETP, &sg_inferior);
+ /* If we only want output, then leave the inferior's pgrp in the
+ foreground, so that Ctrl-C/Ctrl-Z reach the inferior
+ directly. */
+ if (job_control && desired_state == target_terminal_state::is_ours)
+ {
+#ifdef HAVE_TERMIOS_H
+ result = tcsetpgrp (0, our_terminal_info.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 child_terminal_ours: %s]\n",
+ safe_strerror (errno));
+#endif
+#endif /* termios */
+ }
-#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN)
- result = ioctl (0, TIOCGETC, &tc_inferior);
-#endif
-#if defined(TIOCGLTC) && !defined(TIOCGLTC_BROKEN)
- result = ioctl (0, TIOCGLTC, <c_inferior);
+ if (!job_control && desired_state == target_terminal_state::is_ours)
+ {
+ signal (SIGINT, sigint_ours);
+#ifdef SIGQUIT
+ signal (SIGQUIT, sigquit_ours);
#endif
-#ifdef TIOCLGET
- result = ioctl (0, TIOCLGET, &lmode_inferior);
+ }
+
+#ifdef F_GETFL
+ result = fcntl (0, F_SETFL, our_terminal_info.tflags);
#endif
+
+ gdb_tty_state = desired_state;
}
+}
-#ifdef HAVE_TERMIO
- sg_ours.c_lflag |= ICANON;
- if (output_only && !(sg_inferior.c_lflag & ICANON))
- sg_ours.c_lflag &= ~ICANON;
-#else /* not HAVE_TERMIO */
- sg_ours.sg_flags &= ~RAW & ~CBREAK;
- if (output_only)
- sg_ours.sg_flags |= (RAW | CBREAK) & sg_inferior.sg_flags;
-#endif /* not HAVE_TERMIO */
-
- result = fcntl (0, F_SETFL, tflags_ours);
- result = fcntl (0, F_SETFL, tflags_ours);
- result = ioctl (0, TIOCSETN, &sg_ours);
-
-#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN)
- result = ioctl (0, TIOCSETC, &tc_ours);
-#endif
-#if defined(TIOCGLTC) && !defined(TIOCGLTC_BROKEN)
- result = ioctl (0, TIOCSLTC, <c_ours);
+/* Interrupt the inferior. Implementation of target_interrupt for
+ child/native targets. */
+
+void
+child_interrupt (struct target_ops *self)
+{
+ /* Interrupt the first inferior that has a resumed thread. */
+ thread_info *resumed = NULL;
+ for (thread_info *thr : all_non_exited_threads ())
+ {
+ if (thr->executing)
+ {
+ resumed = thr;
+ break;
+ }
+ if (thr->suspend.waitstatus_pending_p)
+ resumed = thr;
+ }
+
+ if (resumed != NULL)
+ {
+ /* Note that unlike pressing Ctrl-C on the controlling terminal,
+ here we only interrupt one process, not the whole process
+ group. This is because interrupting a process group (with
+ either Ctrl-C or with kill(3) with negative PID) sends a
+ SIGINT to each process in the process group, and we may not
+ be debugging all processes in the process group. */
+#ifndef _WIN32
+ kill (resumed->inf->pid, SIGINT);
#endif
-#ifdef TIOCLGET
- result = ioctl (0, TIOCLSET, &lmode_ours);
+ }
+}
+
+/* Pass a Ctrl-C to the inferior as-if a Ctrl-C was pressed while the
+ inferior was in the foreground. Implementation of
+ target_pass_ctrlc for child/native targets. */
+
+void
+child_pass_ctrlc (struct target_ops *self)
+{
+ gdb_assert (!target_terminal::is_ours ());
+
+#ifdef HAVE_TERMIOS_H
+ if (job_control)
+ {
+ pid_t term_pgrp = tcgetpgrp (0);
+
+ /* If there's any inferior sharing our terminal, pass the SIGINT
+ to the terminal's foreground process group. This acts just
+ like the user typed a ^C on the terminal while the inferior
+ was in the foreground. Note that using a negative process
+ number in kill() is a System V-ism. The proper BSD interface
+ is killpg(). However, all modern BSDs support the System V
+ interface too. */
+
+ if (term_pgrp != -1 && term_pgrp != our_terminal_info.process_group)
+ {
+ kill (-term_pgrp, SIGINT);
+ return;
+ }
+ }
#endif
-#ifdef HAVE_TERMIO
- sg_ours.c_lflag |= ICANON;
-#else /* not HAVE_TERMIO */
- sg_ours.sg_flags &= ~RAW & ~CBREAK;
-#endif /* not HAVE_TERMIO */
+ /* Otherwise, pass the Ctrl-C to the first inferior that was resumed
+ in the foreground. */
+ for (inferior *inf : all_inferiors ())
+ {
+ if (inf->terminal_state != target_terminal_state::is_ours)
+ {
+ gdb_assert (inf->pid != 0);
- result = result; /* lint */
+#ifndef _WIN32
+ kill (inf->pid, SIGINT);
#endif
+ return;
+ }
+ }
+
+ /* If no inferior was resumed in the foreground, then how did the
+ !is_ours assert above pass? */
+ gdb_assert_not_reached ("no inferior resumed in the fg found");
+}
+
+/* Per-inferior data key. */
+static const struct inferior_key<terminal_info> inflow_inferior_data;
+
+terminal_info::~terminal_info ()
+{
+ xfree (run_terminal);
+ xfree (ttystate);
+}
+
+/* Get the current svr4 data. If none is found yet, add it now. This
+ function always returns a valid object. */
+
+static struct terminal_info *
+get_inflow_inferior_data (struct inferior *inf)
+{
+ struct terminal_info *info;
+
+ info = inflow_inferior_data.get (inf);
+ if (info == NULL)
+ info = inflow_inferior_data.emplace (inf);
+
+ return info;
+}
+
+/* This is a "inferior_exit" observer. Releases the TERMINAL_INFO member
+ of the inferior structure. This field is private to inflow.c, and
+ its type is opaque to the rest of GDB. PID is the target pid of
+ the inferior that is about to be removed from the inferior
+ list. */
+
+static void
+inflow_inferior_exit (struct inferior *inf)
+{
+ inf->terminal_state = target_terminal_state::is_ours;
+ inflow_inferior_data.clear (inf);
}
-/* ARGSUSED */
void
-term_info (arg, from_tty)
- char *arg;
- int from_tty;
+copy_terminal_info (struct inferior *to, struct inferior *from)
{
- target_terminal_info (arg, from_tty);
+ struct terminal_info *tinfo_to, *tinfo_from;
+
+ tinfo_to = get_inflow_inferior_data (to);
+ tinfo_from = get_inflow_inferior_data (from);
+
+ xfree (tinfo_to->run_terminal);
+ xfree (tinfo_to->ttystate);
+
+ *tinfo_to = *tinfo_from;
+
+ if (tinfo_from->run_terminal)
+ tinfo_to->run_terminal
+ = xstrdup (tinfo_from->run_terminal);
+
+ if (tinfo_from->ttystate)
+ tinfo_to->ttystate
+ = serial_copy_tty_state (stdin_serial, tinfo_from->ttystate);
+
+ to->terminal_state = from->terminal_state;
}
-/* ARGSUSED */
+/* See terminal.h. */
+
void
-child_terminal_info (args, from_tty)
- char *args;
- int from_tty;
+swap_terminal_info (inferior *a, inferior *b)
{
- register int i;
+ terminal_info *info_a = inflow_inferior_data.get (a);
+ terminal_info *info_b = inflow_inferior_data.get (b);
- if (!gdb_has_a_terminal) {
- printf_filtered ("This GDB does not control a terminal.\n");
+ inflow_inferior_data.set (a, info_b);
+ inflow_inferior_data.set (b, info_a);
+
+ std::swap (a->terminal_state, b->terminal_state);
+}
+
+static void
+info_terminal_command (const char *arg, int from_tty)
+{
+ target_terminal::info (arg, from_tty);
+}
+
+void
+child_terminal_info (struct target_ops *self, const char *args, int from_tty)
+{
+ struct inferior *inf;
+ struct terminal_info *tinfo;
+
+ if (!gdb_has_a_terminal ())
+ {
+ printf_filtered (_("This GDB does not control a terminal.\n"));
+ return;
+ }
+
+ if (inferior_ptid == null_ptid)
return;
- }
-#if !defined(__GO32__)
-#ifdef TIOCGPGRP
- printf_filtered ("Inferior's terminal status (currently saved by GDB):\n");
- printf_filtered ("owner pgrp = %d, fcntl flags = 0x%x.\n",
- pgrp_inferior, tflags_inferior);
-#endif /* TIOCGPGRP */
+ inf = current_inferior ();
+ tinfo = get_inflow_inferior_data (inf);
-#ifdef HAVE_TERMIO
+ printf_filtered (_("Inferior's terminal status "
+ "(currently saved by GDB):\n"));
- printf_filtered ("c_iflag = 0x%x, c_oflag = 0x%x,\n",
- sg_inferior.c_iflag, sg_inferior.c_oflag);
- printf_filtered ("c_cflag = 0x%x, c_lflag = 0x%x, c_line = 0x%x.\n",
- sg_inferior.c_cflag, sg_inferior.c_lflag, sg_inferior.c_line);
- printf_filtered ("c_cc: ");
- for (i = 0; (i < NCC); i += 1)
- printf_filtered ("0x%x ", sg_inferior.c_cc[i]);
- printf_filtered ("\n");
+ /* First the fcntl flags. */
+ {
+ int flags;
-#else /* not HAVE_TERMIO */
+ flags = tinfo->tflags;
- printf_filtered ("sgttyb.sg_flags = 0x%x.\n", sg_inferior.sg_flags);
+ printf_filtered ("File descriptor flags = ");
-#endif /* not HAVE_TERMIO */
+#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);
-#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN)
- printf_filtered ("tchars: ");
- for (i = 0; i < (int)sizeof (struct tchars); i++)
- printf_filtered ("0x%x ", ((unsigned char *)&tc_inferior)[i]);
- printf_filtered ("\n");
+#ifdef O_NONBLOCK
+ if (flags & O_NONBLOCK)
+ printf_filtered (" | O_NONBLOCK");
+ flags &= ~O_NONBLOCK;
#endif
-#if defined(TIOCGLTC) && !defined(TIOCGLTC_BROKEN)
- printf_filtered ("ltchars: ");
- for (i = 0; i < (int)sizeof (struct ltchars); i++)
- printf_filtered ("0x%x ", ((unsigned char *)<c_inferior)[i]);
- printf_filtered ("\n");
+#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
-
-#ifdef TIOCLGET
- printf_filtered ("lmode: 0x%x\n", lmode_inferior);
+
+ 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
-#else
- printf_filtered("This is a DOS machine; there is no terminal state\n");
+
+ if (flags)
+ printf_filtered (" | 0x%x", flags);
+ printf_filtered ("\n");
+ }
+
+#ifdef HAVE_TERMIOS_H
+ printf_filtered ("Process group = %d\n", (int) tinfo->process_group);
#endif
+ serial_print_tty_state (stdin_serial, tinfo->ttystate, gdb_stdout);
}
\f
/* NEW_TTY_PREFORK is called before forking a new child process,
the terminal specified in the NEW_TTY_PREFORK call. */
void
-new_tty_prefork (ttyname)
- char *ttyname;
+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 ()
+#if !defined(__GO32__) && !defined(_WIN32)
+/* If RESULT, assumed to be the return value from a system call, is
+ negative, print the error message indicated by errno and exit.
+ MSG should identify the operation that failed. */
+static void
+check_syscall (const char *msg, int result)
{
- register int tty;
- void (*osigttou) ();
+ if (result < 0)
+ {
+ print_sys_errmsg (msg, errno);
+ _exit (1);
+ }
+}
+#endif
+void
+new_tty (void)
+{
if (inferior_thisrun_terminal == 0)
return;
-#if !defined(__GO32__)
+#if !defined(__GO32__) && !defined(_WIN32)
+ int tty;
+
#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);
+ ignore SIGTTOU. */
+ tty = open ("/dev/tty", O_RDWR);
if (tty > 0)
{
- osigttou = (void (*)()) signal(SIGTTOU, SIG_IGN);
- ioctl(tty, TIOCNOTTY, 0);
- close(tty);
- (void) signal(SIGTTOU, osigttou);
+ scoped_ignore_sigttou ignore_sigttou;
+
+ ioctl (tty, TIOCNOTTY, 0);
+ close (tty);
}
#endif
/* Now open the specified new terminal. */
-
-#ifdef USE_O_NOCTTY
- tty = open(inferior_thisrun_terminal, O_RDWR | O_NOCTTY);
-#else
- tty = open(inferior_thisrun_terminal, O_RDWR);
-#endif
- if (tty == -1)
- {
- print_sys_errmsg (inferior_thisrun_terminal, errno);
- _exit(1);
- }
+ tty = open (inferior_thisrun_terminal, O_RDWR | O_NOCTTY);
+ check_syscall (inferior_thisrun_terminal, tty);
/* Avoid use of dup2; doesn't exist on all systems. */
if (tty != 0)
- { close (0); dup (tty); }
+ {
+ close (0);
+ check_syscall ("dup'ing tty into fd 0", dup (tty));
+ }
if (tty != 1)
- { close (1); dup (tty); }
+ {
+ close (1);
+ check_syscall ("dup'ing tty into fd 1", dup (tty));
+ }
if (tty != 2)
- { close (2); dup (tty); }
+ {
+ close (2);
+ check_syscall ("dup'ing tty into fd 2", dup (tty));
+ }
+
+#ifdef TIOCSCTTY
+ /* Make tty our new controlling terminal. */
+ if (ioctl (tty, TIOCSCTTY, 0) == -1)
+ /* Mention GDB in warning because it will appear in the inferior's
+ terminal instead of GDB's. */
+ warning (_("GDB: Failed to set controlling terminal: %s"),
+ safe_strerror (errno));
+#endif
+
if (tty > 2)
- close(tty);
-#endif /* !go32*/o
+ close (tty);
+#endif /* !go32 && !win32 */
}
+
+/* NEW_TTY_POSTFORK is called after forking a new child process, and
+ adding it to the inferior table, to store the TTYNAME being used by
+ the child, or null if it sharing the terminal with gdb. */
+
+void
+new_tty_postfork (void)
+{
+ /* Save the name for later, for determining whether we and the child
+ are sharing a tty. */
+
+ if (inferior_thisrun_terminal)
+ {
+ struct inferior *inf = current_inferior ();
+ struct terminal_info *tinfo = get_inflow_inferior_data (inf);
+
+ tinfo->run_terminal = xstrdup (inferior_thisrun_terminal);
+ }
+
+ inferior_thisrun_terminal = NULL;
+}
+
\f
-/* Kill the inferior process. Make us have no inferior. */
+/* Call set_sigint_trap when you need to pass a signal on to an attached
+ process when handling SIGINT. */
-/* ARGSUSED */
static void
-kill_command (arg, from_tty)
- char *arg;
- int from_tty;
-{
- if (inferior_pid == 0)
- error ("The program is not being run.");
- if (!query ("Kill the inferior process? "))
- error ("Not confirmed.");
- target_kill ();
-
- /* 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", current_target->to_longname);
- if (selected_frame == NULL)
- fputs_filtered ("No selected stack frame.\n", stdout);
- else
- print_stack_frame (selected_frame, selected_frame_level, 1);
- }
+pass_signal (int signo)
+{
+#ifndef _WIN32
+ kill (inferior_ptid.pid (), SIGINT);
+#endif
}
-/* The inferior process has died. Long live the inferior! */
+static sighandler_t osig;
+static int osig_set;
void
-generic_mourn_inferior ()
+set_sigint_trap (void)
{
- inferior_pid = 0;
- attach_flag = 0;
- mark_breakpoints_out ();
- registers_changed ();
-
-#ifdef CLEAR_DEFERRED_STORES
- /* Delete any pending stores to the inferior... */
- CLEAR_DEFERRED_STORES;
-#endif
+ struct inferior *inf = current_inferior ();
+ struct terminal_info *tinfo = get_inflow_inferior_data (inf);
- reopen_exec_file ();
- if (target_has_stack) {
- set_current_frame ( create_new_frame (read_register (FP_REGNUM),
- read_pc ()));
- select_frame (get_current_frame (), 0);
- } else {
- set_current_frame (0);
- select_frame ((FRAME) 0, -1);
- }
- /* It is confusing to the user for ignore counts to stick around
- from previous runs of the inferior. So clear them. */
- breakpoint_clear_ignore_counts ();
+ if (inf->attach_flag || tinfo->run_terminal)
+ {
+ osig = signal (SIGINT, pass_signal);
+ osig_set = 1;
+ }
+ else
+ osig_set = 0;
}
void
-child_mourn_inferior ()
+clear_sigint_trap (void)
{
- unpush_target (&child_ops);
- generic_mourn_inferior ();
-}
-\f
-#if 0
-/* This function is just for testing, and on some systems (Sony NewsOS
- 3.2) <sys/user.h> also includes <sys/time.h> which leads to errors
- (since on this system at least sys/time.h is not protected against
- multiple inclusion). */
-/* ARGSUSED */
-static void
-try_writing_regs_command (arg, from_tty)
- char *arg;
- int from_tty;
-{
- register int i;
- register int value;
-
- if (inferior_pid == 0)
- error ("There is no inferior process now.");
-
- /* A Sun 3/50 or 3/60 (at least) running SunOS 4.0.3 will have a
- kernel panic if we try to write past the end of the user area.
- Presumably Sun will fix this bug (it has been reported), but it
- is tacky to crash the system, so at least on SunOS4 we need to
- stop writing when we hit the end of the user area. */
- for (i = 0; i < sizeof (struct user); i += 2)
+ if (osig_set)
{
- QUIT;
- errno = 0;
- value = call_ptrace (3, inferior_pid, (PTRACE_ARG3_TYPE) i, 0);
- call_ptrace (6, inferior_pid, (PTRACE_ARG3_TYPE) i, value);
- if (errno == 0)
- {
- printf (" Succeeded with address 0x%x; value 0x%x (%d).\n",
- i, value, value);
- }
- else if ((i & 0377) == 0)
- printf (" Failed at 0x%x.\n", i);
+ signal (SIGINT, osig);
+ osig_set = 0;
}
}
-#endif
\f
-void
-_initialize_inflow ()
-{
- int result;
- add_info ("terminal", term_info,
- "Print inferior's saved terminal status.");
+/* Create a new session if the inferior will run in a different tty.
+ A session is UNIX's way of grouping processes that share a controlling
+ terminal, so a new one is needed if the inferior terminal will be
+ different from GDB's.
-#if 0
- add_com ("try-writing-regs", class_obscure, try_writing_regs_command,
- "Try writing all locations in inferior's system block.\n\
-Report which ones can be written.");
-#endif
+ Returns the session id of the new session, 0 if no session was created
+ or -1 if an error occurred. */
+pid_t
+create_tty_session (void)
+{
+#ifdef HAVE_SETSID
+ pid_t ret;
- add_com ("kill", class_run, kill_command,
- "Kill execution of program being debugged.");
+ if (!job_control || inferior_thisrun_terminal == 0)
+ return 0;
- inferior_pid = 0;
+ ret = setsid ();
+ if (ret == -1)
+ warning (_("Failed to create new terminal session: setsid: %s"),
+ safe_strerror (errno));
- /* Get all the current tty settings (including whether we have a tty at
- all!). */
+ return ret;
+#else
+ return 0;
+#endif /* HAVE_SETSID */
+}
-#if !defined(__GO32__)
- tflags_ours = fcntl (0, F_GETFL, 0);
+/* 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);
+}
- result = ioctl (0, TIOCGETP, &sg_ours);
- if (result == 0) {
- gdb_has_a_terminal = 1;
- /* Get the rest of the tty settings, then... */
-#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN)
- ioctl (0, TIOCGETC, &tc_ours);
-#endif
-#if defined(TIOCGLTC) && !defined(TIOCGLTC_BROKEN)
- ioctl (0, TIOCGLTC, <c_ours);
-#endif
-#ifdef TIOCLGET
- ioctl (0, TIOCLGET, &lmode_ours);
-#endif
-#ifdef TIOCGPGRP
- ioctl (0, TIOCGPGRP, &pgrp_ours);
-#endif /* TIOCGPGRP */
- } else {
- gdb_has_a_terminal = 0;
- }
-#else
- gdb_has_a_terminal = 0;
-#endif
+void
+_initialize_inflow (void)
+{
+ add_info ("terminal", info_terminal_command,
+ _("Print inferior's saved terminal status."));
+ /* OK, figure out whether we have job control. */
+ have_job_control ();
- terminal_is_ours = 1;
+ gdb::observers::inferior_exit.attach (inflow_inferior_exit);
}