| /* Fork a Unix child process, and set up to debug it, for GDB. |
| |
| Copyright (C) 1990-2021 Free Software Foundation, Inc. |
| |
| Contributed by Cygnus Support. |
| |
| 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 "defs.h" |
| #include "inferior.h" |
| #include "gdbcmd.h" |
| #include "terminal.h" |
| #include "gdbthread.h" |
| #include "top.h" |
| #include "gdbsupport/job-control.h" |
| #include "gdbsupport/filestuff.h" |
| #include "nat/fork-inferior.h" |
| #include "gdbsupport/common-inferior.h" |
| |
| /* The exec-wrapper, if any, that will be used when starting the |
| inferior. */ |
| |
| static std::string exec_wrapper; |
| |
| /* See gdbsupport/common-inferior.h. */ |
| |
| const char * |
| get_exec_wrapper () |
| { |
| return !exec_wrapper.empty () ? exec_wrapper.c_str () : nullptr; |
| } |
| |
| /* See nat/fork-inferior.h. */ |
| |
| void |
| gdb_flush_out_err () |
| { |
| gdb_flush (main_ui->m_gdb_stdout); |
| gdb_flush (main_ui->m_gdb_stderr); |
| } |
| |
| /* The ui structure that will be saved on 'prefork_hook' and |
| restored on 'postfork_hook'. */ |
| static struct ui *saved_ui = NULL; |
| |
| /* See nat/fork-inferior.h. */ |
| |
| void |
| prefork_hook (const char *args) |
| { |
| gdb_assert (saved_ui == NULL); |
| /* Retain a copy of our UI, since the child will replace this value |
| and if we're vforked, we have to restore it. */ |
| saved_ui = current_ui; |
| |
| /* Tell the terminal handling subsystem what tty we plan to run on; |
| it will just record the information for later. */ |
| new_tty_prefork (current_inferior ()->tty ()); |
| } |
| |
| /* See nat/fork-inferior.h. */ |
| |
| void |
| postfork_hook (pid_t pid) |
| { |
| inferior *inf = current_inferior (); |
| |
| inferior_appeared (inf, pid); |
| |
| gdb_assert (saved_ui != NULL); |
| current_ui = saved_ui; |
| saved_ui = NULL; |
| |
| new_tty_postfork (); |
| } |
| |
| /* See nat/fork-inferior.h. */ |
| |
| void |
| postfork_child_hook () |
| { |
| /* This is set to the result of setpgrp, which if vforked, will be |
| visible to you in the parent process. It's only used by humans |
| for debugging. */ |
| static int debug_setpgrp = 657473; |
| |
| /* Make sure we switch to main_ui here in order to be able to |
| use the fprintf_unfiltered/warning/error functions. */ |
| current_ui = main_ui; |
| |
| /* Create a new session for the inferior process, if necessary. |
| It will also place the inferior in a separate process group. */ |
| if (create_tty_session () <= 0) |
| { |
| /* No session was created, but we still want to run the inferior |
| in a separate process group. */ |
| debug_setpgrp = gdb_setpgid (); |
| if (debug_setpgrp == -1) |
| perror (_("setpgrp failed in child")); |
| } |
| |
| /* Ask the tty subsystem to switch to the one we specified |
| earlier (or to share the current terminal, if none was |
| specified). */ |
| new_tty (); |
| } |
| |
| /* See inferior.h. */ |
| |
| ptid_t |
| gdb_startup_inferior (pid_t pid, int num_traps) |
| { |
| inferior *inf = current_inferior (); |
| process_stratum_target *proc_target = inf->process_target (); |
| |
| ptid_t ptid = startup_inferior (proc_target, pid, num_traps, NULL, NULL); |
| |
| /* Mark all threads non-executing. */ |
| set_executing (proc_target, ptid, false); |
| |
| return ptid; |
| } |
| |
| /* Implement the "unset exec-wrapper" command. */ |
| |
| static void |
| unset_exec_wrapper_command (const char *args, int from_tty) |
| { |
| exec_wrapper.clear (); |
| } |
| |
| static void |
| show_startup_with_shell (struct ui_file *file, int from_tty, |
| struct cmd_list_element *c, const char *value) |
| { |
| fprintf_filtered (file, |
| _("Use of shell to start subprocesses is %s.\n"), |
| value); |
| } |
| |
| void _initialize_fork_child (); |
| void |
| _initialize_fork_child () |
| { |
| add_setshow_filename_cmd ("exec-wrapper", class_run, &exec_wrapper, _("\ |
| Set a wrapper for running programs.\n\ |
| The wrapper prepares the system and environment for the new program."), |
| _("\ |
| Show the wrapper for running programs."), NULL, |
| NULL, NULL, |
| &setlist, &showlist); |
| |
| add_cmd ("exec-wrapper", class_run, unset_exec_wrapper_command, |
| _("Disable use of an execution wrapper."), |
| &unsetlist); |
| |
| add_setshow_boolean_cmd ("startup-with-shell", class_support, |
| &startup_with_shell, _("\ |
| Set use of shell to start subprocesses. The default is on."), _("\ |
| Show use of shell to start subprocesses."), NULL, |
| NULL, |
| show_startup_with_shell, |
| &setlist, &showlist); |
| } |