| /* Low level interface to ptrace, for GDB when running under Unix. |
| Copyright (C) 1986-2024 Free Software Foundation, Inc. |
| |
| This file is part of GDB. |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 3 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| |
| #include "frame.h" |
| #include "inferior.h" |
| #include "command.h" |
| #include "serial.h" |
| #include "terminal.h" |
| #include "target.h" |
| #include "gdbthread.h" |
| #include "observable.h" |
| #include <signal.h> |
| #include <fcntl.h> |
| #include "gdbsupport/gdb_select.h" |
| |
| #include "cli/cli-cmds.h" |
| #ifdef HAVE_TERMIOS_H |
| #include <termios.h> |
| #endif |
| #include "gdbsupport/job-control.h" |
| #include "gdbsupport/scoped_ignore_sigttou.h" |
| |
| #ifdef HAVE_SYS_IOCTL_H |
| #include <sys/ioctl.h> |
| #endif |
| |
| #ifdef __CYGWIN__ |
| #include <sys/cygwin.h> |
| #endif |
| |
| #ifndef O_NOCTTY |
| #define O_NOCTTY 0 |
| #endif |
| |
| static void pass_signal (int); |
| |
| static void child_terminal_ours_1 (target_terminal_state); |
| |
| /* Record terminal status separately for debugger and inferior. */ |
| |
| static struct serial *stdin_serial; |
| |
| /* 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. */ |
| std::string run_terminal; |
| |
| /* 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 std::optional<sighandler_t> sigint_ours; |
| #ifdef SIGQUIT |
| static std::optional<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 std::string 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 |
| } |
| } |
| |
| /* Does GDB have a terminal (on stdin)? */ |
| |
| 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) \ |
| gdb_printf(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 |
| child_terminal_init (struct target_ops *self) |
| { |
| if (!gdb_has_a_terminal ()) |
| return; |
| |
| inferior *inf = current_inferior (); |
| terminal_info *tinfo = get_inflow_inferior_data (inf); |
| |
| #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 |
| |
| 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); |
| } |
| } |
| |
| /* See inferior.h. */ |
| |
| 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); |
| } |
| |
| /* 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 (inf->pid); |
| |
| 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.empty ()) |
| res = is_gdb_terminal (tinfo->run_terminal.c_str ()); |
| |
| /* 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 |
| child_terminal_inferior (struct target_ops *self) |
| { |
| /* 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; |
| |
| inferior *inf = current_inferior (); |
| terminal_info *tinfo = get_inflow_inferior_data (inf); |
| |
| if (gdb_has_a_terminal () |
| && tinfo->ttystate != NULL |
| && sharing_input_terminal (inf)) |
| { |
| 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"); |
| #endif |
| |
| result = serial_set_tty_state (stdin_serial, tinfo->ttystate); |
| OOPSY ("setting tty state"); |
| |
| if (!job_control) |
| { |
| sigint_ours = install_sigint_handler (SIG_IGN); |
| #ifdef SIGQUIT |
| sigquit_ours = signal (SIGQUIT, SIG_IGN); |
| #endif |
| } |
| |
| 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. */ |
| pid_t pgrp = tinfo->process_group; |
| #ifdef __CYGWIN__ |
| /* The Windows native target uses Win32 routines to run or |
| attach to processes (CreateProcess / DebugActiveProcess), |
| so a Cygwin inferior has a Windows PID, rather than a |
| Cygwin PID. We want to pass the Cygwin PID to Cygwin |
| tcsetpgrp if we have a Cygwin inferior, so try to convert |
| first. If we have a non-Cygwin inferior, we'll end up |
| passing down the WINPID to tcsetpgrp, stored in |
| terminal_state::process_group. tcsetpgrp still succeeds |
| in that case, and it seems preferable to switch the |
| foreground pgrp away from GDB, for consistency. */ |
| pid_t cygpid = cygwin_internal (CW_WINPID_TO_CYGWIN_PID, inf->pid); |
| if (cygpid <= cygwin_internal (CW_MAX_CYGWIN_PID)) |
| pgrp = getpgid (cygpid); |
| #elif defined (HAVE_GETPGID) |
| pgrp = getpgid (inf->pid); |
| #endif |
| result = tcsetpgrp (0, pgrp); |
| 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). */ |
| gdb_printf |
| (gdb_stderr, |
| "[tcsetpgrp failed in child_terminal_inferior: %s]\n", |
| safe_strerror (errno)); |
| #endif |
| } |
| #endif |
| } |
| |
| gdb_tty_state = target_terminal_state::is_inferior; |
| } |
| } |
| |
| /* Put some of our terminal settings into effect, |
| enough to get proper results from our output, |
| but do not change into or out of RAW mode |
| so that no input is discarded. |
| |
| After doing this, either terminal_ours or terminal_inferior |
| should be called to get back to a normal state of affairs. |
| |
| N.B. The implementation is (currently) no different than |
| child_terminal_ours. See child_terminal_ours_1. */ |
| |
| void |
| child_terminal_ours_for_output (struct target_ops *self) |
| { |
| 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. |
| |
| 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 |
| 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 |
| 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 (gdb_tty_state != desired_state) |
| { |
| int result ATTRIBUTE_UNUSED; |
| |
| /* Ignore SIGTTOU since it will happen when we try to set the |
| terminal's pgrp. */ |
| scoped_ignore_sigttou ignore_sigttou; |
| |
| /* Set tty state to our_ttystate. */ |
| serial_set_tty_state (stdin_serial, our_terminal_info.ttystate); |
| |
| /* 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) |
| gdb_printf (gdb_stderr, |
| "[tcsetpgrp failed in child_terminal_ours: %s]\n", |
| safe_strerror (errno)); |
| #endif |
| #endif /* termios */ |
| } |
| |
| if (!job_control && desired_state == target_terminal_state::is_ours) |
| { |
| if (sigint_ours.has_value ()) |
| install_sigint_handler (*sigint_ours); |
| sigint_ours.reset (); |
| #ifdef SIGQUIT |
| if (sigquit_ours.has_value ()) |
| signal (SIGQUIT, *sigquit_ours); |
| sigquit_ours.reset (); |
| #endif |
| } |
| |
| #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. */ |
| |
| 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->has_pending_waitstatus ()) |
| 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 |
| } |
| } |
| |
| /* 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 |
| |
| /* 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 registry<inferior>::key<terminal_info> inflow_inferior_data; |
| |
| terminal_info::~terminal_info () |
| { |
| 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->ttystate); |
| |
| *tinfo_to = *tinfo_from; |
| |
| 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); |
| |
| 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 ()) |
| { |
| gdb_printf (_("This GDB does not control a terminal.\n")); |
| return; |
| } |
| |
| if (inferior_ptid == null_ptid) |
| return; |
| |
| inf = current_inferior (); |
| tinfo = get_inflow_inferior_data (inf); |
| |
| gdb_printf (_("Inferior's terminal status " |
| "(currently saved by GDB):\n")); |
| |
| /* First the fcntl flags. */ |
| { |
| int flags; |
| |
| flags = tinfo->tflags; |
| |
| gdb_printf ("File descriptor flags = "); |
| |
| #ifndef O_ACCMODE |
| #define O_ACCMODE (O_RDONLY | O_WRONLY | O_RDWR) |
| #endif |
| /* (O_ACCMODE) parens are to avoid Ultrix header file bug. */ |
| switch (flags & (O_ACCMODE)) |
| { |
| case O_RDONLY: |
| gdb_printf ("O_RDONLY"); |
| break; |
| case O_WRONLY: |
| gdb_printf ("O_WRONLY"); |
| break; |
| case O_RDWR: |
| gdb_printf ("O_RDWR"); |
| break; |
| } |
| flags &= ~(O_ACCMODE); |
| |
| #ifdef O_NONBLOCK |
| if (flags & O_NONBLOCK) |
| gdb_printf (" | O_NONBLOCK"); |
| flags &= ~O_NONBLOCK; |
| #endif |
| |
| #if defined (O_NDELAY) |
| /* If O_NDELAY and O_NONBLOCK are defined to the same thing, we will |
| print it as O_NONBLOCK, which is good cause that is what POSIX |
| has, and the flag will already be cleared by the time we get here. */ |
| if (flags & O_NDELAY) |
| gdb_printf (" | O_NDELAY"); |
| flags &= ~O_NDELAY; |
| #endif |
| |
| if (flags & O_APPEND) |
| gdb_printf (" | O_APPEND"); |
| flags &= ~O_APPEND; |
| |
| #if defined (O_BINARY) |
| if (flags & O_BINARY) |
| gdb_printf (" | O_BINARY"); |
| flags &= ~O_BINARY; |
| #endif |
| |
| if (flags) |
| gdb_printf (" | 0x%x", flags); |
| gdb_printf ("\n"); |
| } |
| |
| #ifdef HAVE_TERMIOS_H |
| gdb_printf ("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 empty if we are to share the terminal with gdb; |
| otherwise it contains 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 (std::string ttyname) |
| { |
| /* Save the name for later, for determining whether we and the child |
| are sharing a tty. */ |
| inferior_thisrun_terminal = std::move (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 |
| check_syscall (const char *msg, int result) |
| { |
| if (result < 0) |
| { |
| gdb_printf (gdb_stderr, "%s:%s.\n", msg, |
| safe_strerror (errno)); |
| _exit (1); |
| } |
| } |
| #endif |
| |
| void |
| new_tty (void) |
| { |
| if (inferior_thisrun_terminal.empty ()) |
| return; |
| #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); |
| if (tty >= 0) |
| { |
| scoped_ignore_sigttou ignore_sigttou; |
| |
| ioctl (tty, TIOCNOTTY, 0); |
| close (tty); |
| } |
| #endif |
| |
| /* Now open the specified new terminal. */ |
| tty = open (inferior_thisrun_terminal.c_str (), O_RDWR | O_NOCTTY); |
| check_syscall (inferior_thisrun_terminal.c_str (), tty); |
| |
| /* Avoid use of dup2; doesn't exist on all systems. */ |
| if (tty != 0) |
| { |
| close (0); |
| check_syscall ("dup'ing tty into fd 0", dup (tty)); |
| } |
| if (tty != 1) |
| { |
| close (1); |
| check_syscall ("dup'ing tty into fd 1", dup (tty)); |
| } |
| if (tty != 2) |
| { |
| 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 && !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 empty 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. */ |
| |
| struct inferior *inf = current_inferior (); |
| struct terminal_info *tinfo = get_inflow_inferior_data (inf); |
| |
| tinfo->run_terminal = std::move (inferior_thisrun_terminal); |
| inferior_thisrun_terminal.clear (); |
| } |
| |
| |
| /* Call set_sigint_trap when you need to pass a signal on to an attached |
| process when handling SIGINT. */ |
| |
| static void |
| pass_signal (int signo) |
| { |
| #ifndef _WIN32 |
| kill (inferior_ptid.pid (), SIGINT); |
| #endif |
| } |
| |
| static sighandler_t osig; |
| static int osig_set; |
| |
| void |
| set_sigint_trap (void) |
| { |
| struct inferior *inf = current_inferior (); |
| struct terminal_info *tinfo = get_inflow_inferior_data (inf); |
| |
| if (inf->attach_flag || !tinfo->run_terminal.empty ()) |
| { |
| osig = install_sigint_handler (pass_signal); |
| osig_set = 1; |
| } |
| else |
| osig_set = 0; |
| } |
| |
| void |
| clear_sigint_trap (void) |
| { |
| if (osig_set) |
| { |
| install_sigint_handler (osig); |
| osig_set = 0; |
| } |
| } |
| |
| |
| /* 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) |
| { |
| #ifdef HAVE_SETSID |
| pid_t ret; |
| |
| if (!job_control || inferior_thisrun_terminal.empty ()) |
| return 0; |
| |
| ret = setsid (); |
| if (ret == -1) |
| warning (_("Failed to create new terminal session: setsid: %s"), |
| safe_strerror (errno)); |
| |
| return ret; |
| #else |
| return 0; |
| #endif /* HAVE_SETSID */ |
| } |
| |
| /* Get all the current tty settings (including whether we have a |
| tty at all!). We can't do this in _initialize_inflow because |
| serial_fdopen() won't work until the serial_ops_list is |
| initialized, but we don't want to do it lazily either, so |
| that we can guarantee stdin_serial is opened if there is |
| a terminal. */ |
| void |
| initialize_stdin_serial (void) |
| { |
| stdin_serial = serial_fdopen (0); |
| } |
| |
| void _initialize_inflow (); |
| void |
| _initialize_inflow () |
| { |
| add_info ("terminal", info_terminal_command, |
| _("Print inferior's saved terminal status.")); |
| |
| /* OK, figure out whether we have job control. */ |
| have_job_control (); |
| |
| gdb::observers::inferior_exit.attach (inflow_inferior_exit, "inflow"); |
| } |