X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=gdb%2Finflow.c;h=c8661796645a5069064cf20bfdad8b6c41491d65;hb=8aaaf7577f070c91086533d959ac36a15d1d604f;hp=5062643f82f8013144cab358c6284a8e4fe5939f;hpb=7a67dd45ca1c191a0220697a3ec9fa92993caf8c;p=deliverable%2Fbinutils-gdb.git diff --git a/gdb/inflow.c b/gdb/inflow.c index 5062643f82..c866179664 100644 --- a/gdb/inflow.c +++ b/gdb/inflow.c @@ -1,174 +1,398 @@ /* Low level interface to ptrace, for GDB when running under Unix. - Copyright (C) 1986, 1987, 1989 Free Software Foundation, Inc. + Copyright (C) 1986-2019 Free Software Foundation, Inc. -This file is part of GDB. + This file is part of GDB. -GDB 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 1, 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. -GDB 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 GDB; see the file COPYING. If not, write to -the Free Software Foundation, 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 . */ -#include #include "defs.h" -#include "param.h" #include "frame.h" #include "inferior.h" - -#ifdef USG -#include -#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 "command.h" +#include "serial.h" +#include "terminal.h" +#include "target.h" +#include "gdbthread.h" +#include "observable.h" +#include #include +#include "gdb_select.h" -#include -#include -#include +#include "inflow.h" +#include "gdbcmd.h" +#ifdef HAVE_TERMIOS_H +#include +#endif +#include "gdbsupport/job-control.h" -#ifdef HAVE_TERMIO -#include -#undef TIOCGETP -#define TIOCGETP TCGETA -#undef TIOCSETN -#define TIOCSETN TCSETA -#undef TIOCSETP -#define TIOCSETP TCSETAF -#define TERMINAL struct termio -#else +#ifdef HAVE_SYS_IOCTL_H #include -#include -#include -#define TERMINAL struct sgttyb #endif -#ifdef SET_STACK_LIMIT_HUGE -#include -#include -extern int original_stack_limit; -#endif /* SET_STACK_LIMIT_HUGE */ - -extern int errno; - -/* 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); /* Record terminal status separately for debugger and inferior. */ -static TERMINAL sg_inferior; -static TERMINAL sg_ours; - -static int tflags_inferior; -static int tflags_ours; +static struct serial *stdin_serial; -#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN) -static struct tchars tc_inferior; -static struct tchars tc_ours; +/* 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 -#ifdef TIOCGLTC -static struct ltchars ltc_inferior; -static struct ltchars ltc_ours; + /* 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 -#ifdef TIOCLGET -static int lmode_inferior; -static int lmode_ours; +/* 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. */ + +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. */ + + initial_gdb_ttystate = serial_get_tty_state (stdin_serial); + + 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 + } +} -#ifdef TIOCGPGRP -static int pgrp_inferior; -static int pgrp_ours; -#else -static int (*sigint_ours) (); -static int (*sigquit_ours) (); -#endif /* TIOCGPGRP */ +/* Does GDB have a terminal (on stdin)? */ -/* Copy of inferior_io_terminal when inferior was last started. */ -static char *inferior_thisrun_terminal; +static int +gdb_has_a_terminal (void) +{ + return initial_gdb_ttystate != NULL; +} -static void terminal_ours_1 (); +/* Macro for printing errors from ioctl operations */ -/* Nonzero if our terminal settings are in effect. - Zero if the inferior's settings are in effect. */ -static int terminal_is_ours; +#define OOPSY(what) \ + if (result == -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 (remote_debugging) + if (!gdb_has_a_terminal ()) return; - sg_inferior = sg_ours; - tflags_inferior = tflags_ours; + inferior *inf = current_inferior (); + terminal_info *tinfo = get_inflow_inferior_data (inf); -#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN) - tc_inferior = tc_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 TIOCGLTC - ltc_inferior = ltc_ours; -#endif + xfree (tinfo->ttystate); + tinfo->ttystate = serial_copy_tty_state (stdin_serial, initial_gdb_ttystate); +} -#ifdef TIOCLGET - lmode_inferior = lmode_ours; +/* 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); +} + +/* 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 +} -#ifdef TIOCGPGRP - pgrp_inferior = inferior_pid; -#endif /* TIOCGPGRP */ +/* 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); - terminal_is_ours = 1; + 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. */ +/* 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 (remote_debugging) + /* 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 (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)) { - fcntl (0, F_SETFL, tflags_inferior); - fcntl (0, F_SETFL, tflags_inferior); - ioctl (0, TIOCSETN, &sg_inferior); + int result; -#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN) - ioctl (0, TIOCSETC, &tc_inferior); -#endif -#ifdef TIOCGLTC - ioctl (0, TIOCSLTC, <c_inferior); + /* 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"); #endif -#ifdef TIOCLGET - ioctl (0, TIOCLSET, &lmode_inferior); + + result = serial_set_tty_state (stdin_serial, tinfo->ttystate); + OOPSY ("setting tty state"); + + if (!job_control) + { + sigint_ours = signal (SIGINT, SIG_IGN); +#ifdef SIGQUIT + sigquit_ours = signal (SIGQUIT, SIG_IGN); #endif + } -#ifdef TIOCGPGRP - ioctl (0, TIOCSPGRP, &pgrp_inferior); + 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 - sigint_ours = (int (*) ()) signal (SIGINT, SIG_IGN); - sigquit_ours = (int (*) ()) signal (SIGQUIT, SIG_IGN); -#endif /* TIOCGPGRP */ + result = tcsetpgrp (0, tinfo->process_group); +#endif + 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 + } + + gdb_tty_state = target_terminal_state::is_inferior; } - terminal_is_ours = 0; } /* Put some of our terminal settings into effect, @@ -177,373 +401,566 @@ terminal_inferior () 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) { - if (remote_debugging) - return; - - 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 +child_terminal_ours (struct target_ops *self) +{ + child_terminal_ours_1 (target_terminal_state::is_ours); +} + +/* Save the current terminal settings in the inferior's terminal_info + cache. */ void -terminal_ours () +child_terminal_save_inferior (struct target_ops *self) { - if (remote_debugging) + /* Avoid attempting all the ioctl's when running in batch. */ + if (!gdb_has_a_terminal ()) return; - terminal_ours_1 (0); + 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; +child_terminal_ours_1 (target_terminal_state desired_state) { -#ifdef TIOCGPGRP - /* Ignore this signal since it will happen when we try to set the pgrp. */ - int (*osigttou) (); -#endif /* TIOCGPGRP */ + gdb_assert (desired_state != target_terminal_state::is_inferior); - if (!terminal_is_ours) /* && inferior_thisrun_terminal == 0) */ - { - terminal_is_ours = 1; + /* Avoid attempting all the ioctl's when running in batch. */ + if (!gdb_has_a_terminal ()) + return; -#ifdef TIOCGPGRP - osigttou = (int (*) ()) signal (SIGTTOU, SIG_IGN); + if (gdb_tty_state != desired_state) + { + int result ATTRIBUTE_UNUSED; - ioctl (0, TIOCGPGRP, &pgrp_inferior); - ioctl (0, TIOCSPGRP, &pgrp_ours); + /* Ignore SIGTTOU since it will happen when we try to set the + terminal's pgrp. */ + scoped_ignore_sigttou ignore_sigttou; - signal (SIGTTOU, osigttou); -#else - signal (SIGINT, sigint_ours); - signal (SIGQUIT, sigquit_ours); -#endif /* TIOCGPGRP */ + /* Set tty state to our_ttystate. */ + serial_set_tty_state (stdin_serial, our_terminal_info.ttystate); - tflags_inferior = fcntl (0, F_GETFL, 0); - ioctl (0, TIOCGETP, &sg_inferior); - -#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN) - ioctl (0, TIOCGETC, &tc_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 -#ifdef TIOCGLTC - ioctl (0, TIOCGLTC, <c_inferior); +#endif /* termios */ + } + + if (!job_control && desired_state == target_terminal_state::is_ours) + { + signal (SIGINT, sigint_ours); +#ifdef SIGQUIT + signal (SIGQUIT, sigquit_ours); #endif -#ifdef TIOCLGET - ioctl (0, TIOCLGET, &lmode_inferior); + } + +#ifdef F_GETFL + result = fcntl (0, F_SETFL, our_terminal_info.tflags); #endif + + gdb_tty_state = desired_state; } +} + +/* Interrupt the inferior. Implementation of target_interrupt for + child/native targets. */ -#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 */ - - fcntl (0, F_SETFL, tflags_ours); - fcntl (0, F_SETFL, tflags_ours); - ioctl (0, TIOCSETN, &sg_ours); - -#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN) - ioctl (0, TIOCSETC, &tc_ours); +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 TIOCGLTC - ioctl (0, TIOCSLTC, <c_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 TIOCLGET - ioctl (0, TIOCLSET, &lmode_ours); + + /* 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); + +#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 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); +} + +void +copy_terminal_info (struct inferior *to, struct inferior *from) +{ + 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; +} + +/* See terminal.h. */ + +void +swap_terminal_info (inferior *a, inferior *b) +{ + terminal_info *info_a = inflow_inferior_data.get (a); + terminal_info *info_b = inflow_inferior_data.get (b); + + inflow_inferior_data.set (a, info_b); + inflow_inferior_data.set (b, info_a); -#ifdef HAVE_TERMIO - sg_ours.c_lflag |= ICANON; -#else /* not HAVE_TERMIO */ - sg_ours.sg_flags &= ~RAW & ~CBREAK; -#endif /* not HAVE_TERMIO */ + std::swap (a->terminal_state, b->terminal_state); } static void -term_status_command () +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) { - register int i; + struct inferior *inf; + struct terminal_info *tinfo; - if (remote_debugging) + if (!gdb_has_a_terminal ()) { - printf_filtered ("No terminal status when remote debugging.\n"); + printf_filtered (_("This GDB does not control a terminal.\n")); return; } - printf_filtered ("Inferior's terminal status (currently saved by GDB):\n"); + if (inferior_ptid == null_ptid) + return; + + 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 ("fcntl flags = 0x%x, c_iflag = 0x%x, c_oflag = 0x%x,\n", - tflags_inferior, 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 ("fcntl flags = 0x%x, sgttyb.sg_flags = 0x%x, owner pid = %d.\n", - tflags_inferior, sg_inferior.sg_flags, pgrp_inferior); + 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); + +#ifdef O_NONBLOCK + if (flags & O_NONBLOCK) + printf_filtered (" | O_NONBLOCK"); + flags &= ~O_NONBLOCK; +#endif -#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN) - printf_filtered ("tchars: "); - for (i = 0; i < sizeof (struct tchars); i++) - printf_filtered ("0x%x ", ((char *)&tc_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 TIOCGLTC - printf_filtered ("ltchars: "); - for (i = 0; i < sizeof (struct ltchars); i++) - printf_filtered ("0x%x ", ((char *)<c_inferior)[i]); - printf_filtered ("\n"); - ioctl (0, TIOCSLTC, <c_ours); + 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 - -#ifdef TIOCLGET - printf_filtered ("lmode: %x\n", lmode_inferior); + + 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); } +/* 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; +} + +#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 -new_tty (ttyname) - char *ttyname; +check_syscall (const char *msg, int result) { - register int tty; - register int fd; + if (result < 0) + { + print_sys_errmsg (msg, errno); + _exit (1); + } +} +#endif + +void +new_tty (void) +{ + if (inferior_thisrun_terminal == 0) + return; +#if !defined(__GO32__) && !defined(_WIN32) + int tty; #ifdef TIOCNOTTY - /* Disconnect the child process from our controlling terminal. */ - tty = open("/dev/tty", O_RDWR); + /* 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) { - ioctl(tty, TIOCNOTTY, 0); - close(tty); + scoped_ignore_sigttou ignore_sigttou; + + ioctl (tty, TIOCNOTTY, 0); + close (tty); } #endif /* Now open the specified new terminal. */ - - tty = open(ttyname, O_RDWR); - if (tty == -1) - _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); } - if (tty > 2) - close(tty); -} - -/* Start an inferior process and returns its pid. - ALLARGS is a string containing shell command to run the program. - ENV is the environment vector to pass. */ + { + close (2); + check_syscall ("dup'ing tty into fd 2", dup (tty)); + } -#ifndef SHELL_FILE -#define SHELL_FILE "/bin/sh" +#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 -int -create_inferior (allargs, env) - char *allargs; - char **env; -{ - int pid; - char *shell_command; - extern int sys_nerr; - extern char *sys_errlist[]; - extern int errno; - - /* If desired, concat something onto the front of ALLARGS. - SHELL_COMMAND is the result. */ -#ifdef SHELL_COMMAND_CONCAT - shell_command = (char *) alloca (strlen (SHELL_COMMAND_CONCAT) + strlen (allargs) + 1); - strcpy (shell_command, SHELL_COMMAND_CONCAT); - strcat (shell_command, allargs); -#else - shell_command = allargs; -#endif + if (tty > 2) + close (tty); +#endif /* !go32 && !win32 */ +} - /* exec is said to fail if the executable is open. */ - close_exec_file (); +/* 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. */ -#if defined(USG) && !defined(HAVE_VFORK) - pid = fork (); -#else - pid = vfork (); -#endif - - if (pid < 0) - perror_with_name ("vfork"); +void +new_tty_postfork (void) +{ + /* Save the name for later, for determining whether we and the child + are sharing a tty. */ - if (pid == 0) + if (inferior_thisrun_terminal) { -#ifdef TIOCGPGRP - /* Run inferior in a separate process group. */ - setpgrp (getpid (), getpid ()); -#endif /* TIOCGPGRP */ - -#ifdef SET_STACK_LIMIT_HUGE - /* Reset the stack limit back to what it was. */ - { - struct rlimit rlim; - - getrlimit (RLIMIT_STACK, &rlim); - rlim.rlim_cur = original_stack_limit; - setrlimit (RLIMIT_STACK, &rlim); - } -#endif /* SET_STACK_LIMIT_HUGE */ + struct inferior *inf = current_inferior (); + struct terminal_info *tinfo = get_inflow_inferior_data (inf); - - inferior_thisrun_terminal = inferior_io_terminal; - if (inferior_io_terminal != 0) - new_tty (inferior_io_terminal); - -/* It seems that changing the signal handlers for the inferior after - a vfork also changes them for the superior. See comments in - initialize_signals for how we get the right signal handlers - for the inferior. */ -/* Not needed on Sun, at least, and loses there - because it clobbers the superior. */ -/*??? signal (SIGQUIT, SIG_DFL); - signal (SIGINT, SIG_DFL); */ - - call_ptrace (0); - execle (SHELL_FILE, "sh", "-c", shell_command, 0, env); - - fprintf (stderr, "Cannot exec %s: %s.\n", SHELL_FILE, - errno < sys_nerr ? sys_errlist[errno] : "unknown error"); - fflush (stderr); - _exit (0177); + tinfo->run_terminal = xstrdup (inferior_thisrun_terminal); } -#ifdef CREATE_INFERIOR_HOOK - CREATE_INFERIOR_HOOK (pid); -#endif - return pid; + inferior_thisrun_terminal = NULL; } -/* 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. */ static void -kill_command () +pass_signal (int signo) { - if (remote_debugging) - return; - if (inferior_pid == 0) - error ("The program is not being run."); - if (!query ("Kill the inferior process? ")) - error ("Not confirmed."); - kill_inferior (); +#ifndef _WIN32 + kill (inferior_ptid.pid (), SIGINT); +#endif } +static sighandler_t osig; +static int osig_set; + void -inferior_died () -{ - inferior_pid = 0; - attach_flag = 0; - mark_breakpoints_out (); - select_frame ((FRAME) 0, -1); - reopen_exec_file (); - if (have_core_file_p ()) - set_current_frame ( create_new_frame (read_register (FP_REGNUM), - read_pc ())); - else - set_current_frame (0); -} - -#if 0 -/* This function is just for testing, and on some systems (Sony NewsOS - 3.2) also includes which leads to errors - (since on this system at least sys/time.h is not protected against - multiple inclusion). */ -static void -try_writing_regs_command () +set_sigint_trap (void) { - register int i; - register int value; - extern int errno; + struct inferior *inf = current_inferior (); + struct terminal_info *tinfo = get_inflow_inferior_data (inf); - if (inferior_pid == 0) - error ("There is no inferior process now."); + if (inf->attach_flag || tinfo->run_terminal) + { + osig = signal (SIGINT, pass_signal); + osig_set = 1; + } + else + osig_set = 0; +} - /* 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) +void +clear_sigint_trap (void) +{ + if (osig_set) { - QUIT; - errno = 0; - value = call_ptrace (3, inferior_pid, i, 0); - call_ptrace (6, inferior_pid, 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 -void -_initialize_inflow () + +/* 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. + + 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) { - add_com ("term-status", class_obscure, term_status_command, - "Print info on inferior's saved terminal status."); +#ifdef HAVE_SETSID + pid_t ret; -#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 + if (!job_control || inferior_thisrun_terminal == 0) + return 0; - add_com ("kill", class_run, kill_command, - "Kill execution of program being debugged."); + ret = setsid (); + if (ret == -1) + warning (_("Failed to create new terminal session: setsid: %s"), + safe_strerror (errno)); - inferior_pid = 0; + return ret; +#else + return 0; +#endif /* HAVE_SETSID */ +} - ioctl (0, TIOCGETP, &sg_ours); - fcntl (0, F_GETFL, tflags_ours); +/* 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); +} -#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN) - ioctl (0, TIOCGETC, &tc_ours); -#endif -#ifdef TIOCGLTC - ioctl (0, TIOCGLTC, <c_ours); -#endif -#ifdef TIOCLGET - ioctl (0, TIOCLGET, &lmode_ours); -#endif +void +_initialize_inflow (void) +{ + add_info ("terminal", info_terminal_command, + _("Print inferior's saved terminal status.")); -#ifdef TIOCGPGRP - ioctl (0, TIOCGPGRP, &pgrp_ours); -#endif /* TIOCGPGRP */ + /* OK, figure out whether we have job control. */ + have_job_control (); - terminal_is_ours = 1; + gdb::observers::inferior_exit.attach (inflow_inferior_exit); } -