mirror of
https://sourceware.org/git/binutils-gdb.git
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08b8a139c9
This rewrites registry.h, removing all the macros and replacing it with relatively ordinary template classes. The result is less code than the previous setup. It replaces large macros with a relatively straightforward C++ class, and now manages its own cleanup. The existing type-safe "key" class is replaced with the equivalent template class. This approach ended up requiring relatively few changes to the users of the registry code in gdb -- code using the key system just required a small change to the key's declaration. All existing users of the old C-like API are now converted to use the type-safe API. This mostly involved changing explicit deletion functions to be an operator() in a deleter class. The old "save/free" two-phase process is removed, and replaced with a single "free" phase. No existing code used both phases. The old "free" callbacks took a parameter for the enclosing container object. However, this wasn't truly needed and is removed here as well.
958 lines
27 KiB
C
958 lines
27 KiB
C
/* Low level interface to ptrace, for GDB when running under Unix.
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Copyright (C) 1986-2022 Free Software Foundation, Inc.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>. */
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#include "defs.h"
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#include "frame.h"
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#include "inferior.h"
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#include "command.h"
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#include "serial.h"
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#include "terminal.h"
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#include "target.h"
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#include "gdbthread.h"
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#include "observable.h"
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#include <signal.h>
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#include <fcntl.h>
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#include "gdbsupport/gdb_select.h"
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#include "gdbcmd.h"
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#ifdef HAVE_TERMIOS_H
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#include <termios.h>
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#endif
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#include "gdbsupport/job-control.h"
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#include "gdbsupport/scoped_ignore_sigttou.h"
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#ifdef HAVE_SYS_IOCTL_H
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#include <sys/ioctl.h>
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#endif
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#ifndef O_NOCTTY
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#define O_NOCTTY 0
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#endif
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static void pass_signal (int);
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static void child_terminal_ours_1 (target_terminal_state);
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/* Record terminal status separately for debugger and inferior. */
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static struct serial *stdin_serial;
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/* Terminal related info we need to keep track of. Each inferior
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holds an instance of this structure --- we save it whenever the
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corresponding inferior stops, and restore it to the terminal when
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the inferior is resumed in the foreground. */
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struct terminal_info
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{
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terminal_info () = default;
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~terminal_info ();
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terminal_info &operator= (const terminal_info &) = default;
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/* The name of the tty (from the `tty' command) that we gave to the
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inferior when it was started. */
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std::string run_terminal;
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/* TTY state. We save it whenever the inferior stops, and restore
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it when it resumes in the foreground. */
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serial_ttystate ttystate {};
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#ifdef HAVE_TERMIOS_H
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/* The terminal's foreground process group. Saved whenever the
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inferior stops. This is the pgrp displayed by "info terminal".
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Note that this may be not the inferior's actual process group,
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since each inferior that we spawn has its own process group, and
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only one can be in the foreground at a time. When the inferior
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resumes, if we can determine the inferior's actual pgrp, then we
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make that the foreground pgrp instead of what was saved here.
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While it's a bit arbitrary which inferior's pgrp ends up in the
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foreground when we resume several inferiors, this at least makes
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'resume inf1+inf2' + 'stop all' + 'resume inf2' end up with
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inf2's pgrp in the foreground instead of inf1's (which would be
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problematic since it would be left stopped: Ctrl-C wouldn't work,
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for example). */
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pid_t process_group = 0;
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#endif
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/* fcntl flags. Saved and restored just like ttystate. */
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int tflags = 0;
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};
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/* Our own tty state, which we restore every time we need to deal with
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the terminal. This is set once, when GDB first starts, and then
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whenever we enter/leave TUI mode (gdb_save_tty_state). The
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settings of flags which readline saves and restores are
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unimportant. */
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static struct terminal_info our_terminal_info;
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/* Snapshot of the initial tty state taken during initialization of
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GDB, before readline/ncurses have had a chance to change it. This
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is used as the initial tty state given to each new spawned
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inferior. Unlike our_terminal_info, this is only ever set
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once. */
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static serial_ttystate initial_gdb_ttystate;
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static struct terminal_info *get_inflow_inferior_data (struct inferior *);
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/* While the inferior is running, we want SIGINT and SIGQUIT to go to the
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inferior only. If we have job control, that takes care of it. If not,
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we save our handlers in these two variables and set SIGINT and SIGQUIT
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to SIG_IGN. */
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static sighandler_t sigint_ours;
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#ifdef SIGQUIT
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static sighandler_t sigquit_ours;
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#endif
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/* The name of the tty (from the `tty' command) that we're giving to
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the inferior when starting it up. This is only (and should only
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be) used as a transient global by new_tty_prefork,
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create_tty_session, new_tty and new_tty_postfork, all called from
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fork_inferior, while forking a new child. */
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static std::string inferior_thisrun_terminal;
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/* Track who owns GDB's terminal (is it GDB or some inferior?). While
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target_terminal::is_ours() etc. tracks the core's intention and is
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independent of the target backend, this tracks the actual state of
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GDB's own tty. So for example,
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(target_terminal::is_inferior () && gdb_tty_state == terminal_is_ours)
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is true when the (native) inferior is not sharing a terminal with
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GDB (e.g., because we attached to an inferior that is running on a
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different terminal). */
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static target_terminal_state gdb_tty_state = target_terminal_state::is_ours;
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/* See terminal.h. */
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void
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set_initial_gdb_ttystate (void)
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{
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/* Note we can't do any of this in _initialize_inflow because at
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that point stdin_serial has not been created yet. */
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initial_gdb_ttystate = serial_get_tty_state (stdin_serial);
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if (initial_gdb_ttystate != NULL)
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{
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our_terminal_info.ttystate
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= serial_copy_tty_state (stdin_serial, initial_gdb_ttystate);
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#ifdef F_GETFL
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our_terminal_info.tflags = fcntl (0, F_GETFL, 0);
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#endif
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#ifdef HAVE_TERMIOS_H
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our_terminal_info.process_group = tcgetpgrp (0);
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#endif
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}
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}
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/* Does GDB have a terminal (on stdin)? */
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static int
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gdb_has_a_terminal (void)
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{
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return initial_gdb_ttystate != NULL;
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}
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/* Macro for printing errors from ioctl operations */
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#define OOPSY(what) \
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if (result == -1) \
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gdb_printf(gdb_stderr, "[%s failed in terminal_inferior: %s]\n", \
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what, safe_strerror (errno))
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/* Initialize the terminal settings we record for the inferior,
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before we actually run the inferior. */
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void
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child_terminal_init (struct target_ops *self)
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{
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if (!gdb_has_a_terminal ())
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return;
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inferior *inf = current_inferior ();
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terminal_info *tinfo = get_inflow_inferior_data (inf);
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#ifdef HAVE_TERMIOS_H
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/* A child we spawn should be a process group leader (PGID==PID) at
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this point, though that may not be true if we're attaching to an
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existing process. */
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tinfo->process_group = inf->pid;
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#endif
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xfree (tinfo->ttystate);
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tinfo->ttystate = serial_copy_tty_state (stdin_serial, initial_gdb_ttystate);
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}
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/* Save the terminal settings again. This is necessary for the TUI
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when it switches to TUI or non-TUI mode; curses changes the terminal
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and gdb must be able to restore it correctly. */
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void
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gdb_save_tty_state (void)
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{
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if (gdb_has_a_terminal ())
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{
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xfree (our_terminal_info.ttystate);
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our_terminal_info.ttystate = serial_get_tty_state (stdin_serial);
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}
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}
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/* Try to determine whether TTY is GDB's input terminal. Returns
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TRIBOOL_UNKNOWN if we can't tell. */
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static tribool
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is_gdb_terminal (const char *tty)
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{
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struct stat gdb_tty;
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struct stat other_tty;
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int res;
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res = stat (tty, &other_tty);
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if (res == -1)
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return TRIBOOL_UNKNOWN;
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res = fstat (STDIN_FILENO, &gdb_tty);
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if (res == -1)
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return TRIBOOL_UNKNOWN;
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return ((gdb_tty.st_dev == other_tty.st_dev
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&& gdb_tty.st_ino == other_tty.st_ino)
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? TRIBOOL_TRUE
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: TRIBOOL_FALSE);
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}
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/* Helper for sharing_input_terminal. Try to determine whether
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inferior INF is using the same TTY for input as GDB is. Returns
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TRIBOOL_UNKNOWN if we can't tell. */
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static tribool
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sharing_input_terminal_1 (inferior *inf)
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{
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/* Using host-dependent code here is fine, because the
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child_terminal_foo functions are meant to be used by child/native
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targets. */
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#if defined (__linux__) || defined (__sun__)
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char buf[100];
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xsnprintf (buf, sizeof (buf), "/proc/%d/fd/0", inf->pid);
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return is_gdb_terminal (buf);
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#else
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return TRIBOOL_UNKNOWN;
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#endif
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}
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/* Return true if the inferior is using the same TTY for input as GDB
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is. If this is true, then we save/restore terminal flags/state.
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This is necessary because if inf->attach_flag is set, we don't
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offhand know whether we are sharing a terminal with the inferior or
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not. Attaching a process without a terminal is one case where we
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do not; attaching a process which we ran from the same shell as GDB
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via `&' is one case where we do.
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If we can't determine, we assume the TTY is being shared. This
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works OK if you're only debugging one inferior. However, if you're
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debugging more than one inferior, and e.g., one is spawned by GDB
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with "run" (sharing terminal with GDB), and another is attached to
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(and running on a different terminal, as is most common), then it
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matters, because we can only restore the terminal settings of one
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of the inferiors, and in that scenario, we want to restore the
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settings of the "run"'ed inferior.
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Note, this is not the same as determining whether GDB and the
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inferior are in the same session / connected to the same
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controlling tty. An inferior (fork child) may call setsid,
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disconnecting itself from the ctty, while still leaving
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stdin/stdout/stderr associated with the original terminal. If
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we're debugging that process, we should also save/restore terminal
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settings. */
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static bool
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sharing_input_terminal (inferior *inf)
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{
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terminal_info *tinfo = get_inflow_inferior_data (inf);
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tribool res = sharing_input_terminal_1 (inf);
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if (res == TRIBOOL_UNKNOWN)
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{
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/* As fallback, if we can't determine by stat'ing the inferior's
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tty directly (because it's not supported on this host) and
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the child was spawned, check whether run_terminal is our tty.
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This isn't ideal, since this is checking the child's
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controlling terminal, not the input terminal (which may have
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been redirected), but is still better than nothing. A false
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positive ("set inferior-tty" points to our terminal, but I/O
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was redirected) is much more likely than a false negative
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("set inferior-tty" points to some other terminal, and then
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output was redirected to our terminal), and with a false
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positive we just end up trying to save/restore terminal
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settings when we didn't need to or we actually can't. */
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if (!tinfo->run_terminal.empty ())
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res = is_gdb_terminal (tinfo->run_terminal.c_str ());
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/* If we still can't determine, assume yes. */
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if (res == TRIBOOL_UNKNOWN)
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return true;
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}
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return res == TRIBOOL_TRUE;
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}
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/* Put the inferior's terminal settings into effect. This is
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preparation for starting or resuming the inferior. */
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void
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child_terminal_inferior (struct target_ops *self)
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{
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/* If we resume more than one inferior in the foreground on GDB's
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terminal, then the first inferior's terminal settings "win".
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Note that every child process is put in its own process group, so
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the first process that ends up resumed ends up determining which
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process group the kernel forwards Ctrl-C/Ctrl-Z (SIGINT/SIGTTOU)
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to. */
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if (gdb_tty_state == target_terminal_state::is_inferior)
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return;
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inferior *inf = current_inferior ();
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terminal_info *tinfo = get_inflow_inferior_data (inf);
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if (gdb_has_a_terminal ()
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&& tinfo->ttystate != NULL
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&& sharing_input_terminal (inf))
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{
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int result;
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/* Ignore SIGTTOU since it will happen when we try to set the
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terminal's state (if gdb_tty_state is currently
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ours_for_output). */
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scoped_ignore_sigttou ignore_sigttou;
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#ifdef F_GETFL
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result = fcntl (0, F_SETFL, tinfo->tflags);
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OOPSY ("fcntl F_SETFL");
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#endif
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result = serial_set_tty_state (stdin_serial, tinfo->ttystate);
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OOPSY ("setting tty state");
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if (!job_control)
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{
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sigint_ours = signal (SIGINT, SIG_IGN);
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#ifdef SIGQUIT
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sigquit_ours = signal (SIGQUIT, SIG_IGN);
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#endif
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}
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if (job_control)
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{
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#ifdef HAVE_TERMIOS_H
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/* If we can't tell the inferior's actual process group,
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then restore whatever was the foreground pgrp the last
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time the inferior was running. See also comments
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describing terminal_state::process_group. */
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#ifdef HAVE_GETPGID
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result = tcsetpgrp (0, getpgid (inf->pid));
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#else
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result = tcsetpgrp (0, tinfo->process_group);
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#endif
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if (result == -1)
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{
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#if 0
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/* This fails if either GDB has no controlling terminal,
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e.g., running under 'setsid(1)', or if the inferior
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is not attached to GDB's controlling terminal. E.g.,
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if it called setsid to create a new session or used
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the TIOCNOTTY ioctl, or simply if we've attached to a
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process running on another terminal and we couldn't
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tell whether it was sharing GDB's terminal (and so
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assumed yes). */
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gdb_printf
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(gdb_stderr,
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"[tcsetpgrp failed in child_terminal_inferior: %s]\n",
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safe_strerror (errno));
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#endif
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}
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#endif
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}
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gdb_tty_state = target_terminal_state::is_inferior;
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}
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}
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/* Put some of our terminal settings into effect,
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enough to get proper results from our output,
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but do not change into or out of RAW mode
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so that no input is discarded.
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After doing this, either terminal_ours or terminal_inferior
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should be called to get back to a normal state of affairs.
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N.B. The implementation is (currently) no different than
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child_terminal_ours. See child_terminal_ours_1. */
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void
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child_terminal_ours_for_output (struct target_ops *self)
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{
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child_terminal_ours_1 (target_terminal_state::is_ours_for_output);
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}
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/* Put our terminal settings into effect.
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First record the inferior's terminal settings
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so they can be restored properly later.
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N.B. Targets that want to use this with async support must build that
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support on top of this (e.g., the caller still needs to add stdin to the
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event loop). E.g., see linux_nat_terminal_ours. */
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void
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child_terminal_ours (struct target_ops *self)
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{
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child_terminal_ours_1 (target_terminal_state::is_ours);
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}
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/* Save the current terminal settings in the inferior's terminal_info
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cache. */
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void
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child_terminal_save_inferior (struct target_ops *self)
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{
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/* Avoid attempting all the ioctl's when running in batch. */
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if (!gdb_has_a_terminal ())
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return;
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inferior *inf = current_inferior ();
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terminal_info *tinfo = get_inflow_inferior_data (inf);
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/* No need to save/restore if the inferior is not sharing GDB's
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tty. */
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if (!sharing_input_terminal (inf))
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return;
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xfree (tinfo->ttystate);
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tinfo->ttystate = serial_get_tty_state (stdin_serial);
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#ifdef HAVE_TERMIOS_H
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tinfo->process_group = tcgetpgrp (0);
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#endif
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#ifdef F_GETFL
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tinfo->tflags = fcntl (0, F_GETFL, 0);
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#endif
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}
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/* Switch terminal state to DESIRED_STATE, either is_ours, or
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is_ours_for_output. */
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static void
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child_terminal_ours_1 (target_terminal_state desired_state)
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{
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gdb_assert (desired_state != target_terminal_state::is_inferior);
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/* Avoid attempting all the ioctl's when running in batch. */
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if (!gdb_has_a_terminal ())
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return;
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if (gdb_tty_state != desired_state)
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{
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int result ATTRIBUTE_UNUSED;
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/* Ignore SIGTTOU since it will happen when we try to set the
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terminal's pgrp. */
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scoped_ignore_sigttou ignore_sigttou;
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/* Set tty state to our_ttystate. */
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serial_set_tty_state (stdin_serial, our_terminal_info.ttystate);
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/* If we only want output, then leave the inferior's pgrp in the
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foreground, so that Ctrl-C/Ctrl-Z reach the inferior
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directly. */
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if (job_control && desired_state == target_terminal_state::is_ours)
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{
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#ifdef HAVE_TERMIOS_H
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result = tcsetpgrp (0, our_terminal_info.process_group);
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#if 0
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/* This fails on Ultrix with EINVAL if you run the testsuite
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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)
|
||
{
|
||
signal (SIGINT, sigint_ours);
|
||
#ifdef SIGQUIT
|
||
signal (SIGQUIT, sigquit_ours);
|
||
#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)
|
||
{
|
||
print_sys_errmsg (msg, 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 = signal (SIGINT, pass_signal);
|
||
osig_set = 1;
|
||
}
|
||
else
|
||
osig_set = 0;
|
||
}
|
||
|
||
void
|
||
clear_sigint_trap (void)
|
||
{
|
||
if (osig_set)
|
||
{
|
||
signal (SIGINT, 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");
|
||
}
|