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diff --git a/gdb/inflow.c b/gdb/inflow.c
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+/* Low level interface to ptrace, for GDB when running under Unix.
+ Copyright 1986-87, 1989, 1991-92, 1995, 1998 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 2 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, write to the Free Software
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+
+#include "defs.h"
+#include "frame.h"
+#include "inferior.h"
+#include "command.h"
+#include "signals.h"
+#include "serial.h"
+#include "terminal.h"
+#include "target.h"
+#include "gdbthread.h"
+
+#include "gdb_string.h"
+#include <signal.h>
+#include <fcntl.h>
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#ifdef HAVE_TERMIOS
+#define PROCESS_GROUP_TYPE pid_t
+#endif
+
+#ifdef HAVE_TERMIO
+#define PROCESS_GROUP_TYPE int
+#endif
+
+#ifdef HAVE_SGTTY
+#ifdef SHORT_PGRP
+/* This is only used for the ultra. Does it have pid_t? */
+#define PROCESS_GROUP_TYPE short
+#else
+#define PROCESS_GROUP_TYPE int
+#endif
+#endif /* sgtty */
+
+#if defined (SIGIO) && defined (FASYNC) && defined (FD_SET) && defined (F_SETOWN)
+static void
+handle_sigio PARAMS ((int));
+#endif
+
+static void
+pass_signal PARAMS ((int));
+
+static void
+kill_command PARAMS ((char *, int));
+
+static void
+terminal_ours_1 PARAMS ((int));
+
+/* Record terminal status separately for debugger and inferior. */
+
+static serial_t stdin_serial;
+
+/* TTY state for the inferior. We save it whenever the inferior stops, and
+ restore it when it resumes. */
+static serial_ttystate inferior_ttystate;
+
+/* Our own tty state, which we restore every time we need to deal with the
+ terminal. We only set it once, when GDB first starts. The settings of
+ flags which readline saves and restores and unimportant. */
+static serial_ttystate our_ttystate;
+
+/* fcntl flags for us and the inferior. Saved and restored just like
+ {our,inferior}_ttystate. */
+static int tflags_inferior;
+static int tflags_ours;
+
+#ifdef PROCESS_GROUP_TYPE
+/* Process group for us and the inferior. Saved and restored just like
+ {our,inferior}_ttystate. */
+PROCESS_GROUP_TYPE our_process_group;
+PROCESS_GROUP_TYPE inferior_process_group;
+#endif
+
+/* 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 void (*sigint_ours) ();
+static void (*sigquit_ours) ();
+
+/* The name of the tty (from the `tty' command) that we gave to the inferior
+ when it was last started. */
+
+static char *inferior_thisrun_terminal;
+
+/* Nonzero if our terminal settings are in effect. Zero if the
+ inferior's settings are in effect. Ignored if !gdb_has_a_terminal
+ (). */
+
+int terminal_is_ours;
+
+enum {yes, no, have_not_checked} gdb_has_a_terminal_flag = have_not_checked;
+
+/* Does GDB have a terminal (on stdin)? */
+int
+gdb_has_a_terminal ()
+{
+ switch (gdb_has_a_terminal_flag)
+ {
+ case yes:
+ return 1;
+ case no:
+ return 0;
+ case have_not_checked:
+ /* Get all the current tty settings (including whether we have a tty at
+ all!). Can't do this in _initialize_inflow because SERIAL_FDOPEN
+ won't work until the serial_ops_list is initialized. */
+
+#ifdef F_GETFL
+ tflags_ours = fcntl (0, F_GETFL, 0);
+#endif
+
+ gdb_has_a_terminal_flag = no;
+ stdin_serial = SERIAL_FDOPEN (0);
+ if (stdin_serial != NULL)
+ {
+ our_ttystate = SERIAL_GET_TTY_STATE (stdin_serial);
+
+ if (our_ttystate != NULL)
+ {
+ gdb_has_a_terminal_flag = yes;
+#ifdef HAVE_TERMIOS
+ our_process_group = tcgetpgrp (0);
+#endif
+#ifdef HAVE_TERMIO
+ our_process_group = getpgrp ();
+#endif
+#ifdef HAVE_SGTTY
+ ioctl (0, TIOCGPGRP, &our_process_group);
+#endif
+ }
+ }
+
+ return gdb_has_a_terminal_flag == yes;
+ default:
+ /* "Can't happen". */
+ return 0;
+ }
+}
+
+/* Macro for printing errors from ioctl operations */
+
+#define OOPSY(what) \
+ if (result == -1) \
+ fprintf_unfiltered(gdb_stderr, "[%s failed in terminal_inferior: %s]\n", \
+ what, strerror (errno))
+
+static void terminal_ours_1 PARAMS ((int));
+
+/* Initialize the terminal settings we record for the inferior,
+ before we actually run the inferior. */
+
+void
+terminal_init_inferior_with_pgrp (pgrp)
+ int pgrp;
+{
+ if (gdb_has_a_terminal ())
+ {
+ /* We could just as well copy our_ttystate (if we felt like adding
+ a new function SERIAL_COPY_TTY_STATE). */
+ if (inferior_ttystate)
+ free (inferior_ttystate);
+ inferior_ttystate = SERIAL_GET_TTY_STATE (stdin_serial);
+
+#ifdef PROCESS_GROUP_TYPE
+ inferior_process_group = pgrp;
+#endif
+
+ /* Make sure that next time we call terminal_inferior (which will be
+ before the program runs, as it needs to be), we install the new
+ process group. */
+ terminal_is_ours = 1;
+ }
+}
+
+void
+terminal_init_inferior ()
+{
+#ifdef PROCESS_GROUP_TYPE
+ /* This is for Lynx, and should be cleaned up by having Lynx be a separate
+ debugging target with a version of target_terminal_init_inferior which
+ passes in the process group to a generic routine which does all the work
+ (and the non-threaded child_terminal_init_inferior can just pass in
+ inferior_pid to the same routine). */
+ /* We assume INFERIOR_PID is also the child's process group. */
+ terminal_init_inferior_with_pgrp (PIDGET (inferior_pid));
+#endif /* PROCESS_GROUP_TYPE */
+}
+
+/* Put the inferior's terminal settings into effect.
+ This is preparation for starting or resuming the inferior. */
+
+void
+terminal_inferior ()
+{
+ if (gdb_has_a_terminal () && terminal_is_ours
+ && inferior_thisrun_terminal == 0)
+ {
+ int result;
+
+#ifdef F_GETFL
+ /* Is there a reason this is being done twice? It happens both
+ places we use F_SETFL, so I'm inclined to think perhaps there
+ is some reason, however perverse. Perhaps not though... */
+ result = fcntl (0, F_SETFL, tflags_inferior);
+ result = fcntl (0, F_SETFL, tflags_inferior);
+ OOPSY ("fcntl F_SETFL");
+#endif
+
+ /* Because we were careful to not change in or out of raw mode in
+ terminal_ours, we will not change in our out of raw mode with
+ this call, so we don't flush any input. */
+ result = SERIAL_SET_TTY_STATE (stdin_serial, inferior_ttystate);
+ OOPSY ("setting tty state");
+
+ if (!job_control)
+ {
+ sigint_ours = (void (*) ()) signal (SIGINT, SIG_IGN);
+#ifdef SIGQUIT
+ sigquit_ours = (void (*) ()) signal (SIGQUIT, SIG_IGN);
+#endif
+ }
+
+ /* If attach_flag is set, we don't 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, I think (but perhaps this is not
+ `sharing' in the sense that we need to save and restore tty
+ state)). I don't know if there is any way to tell whether we
+ are sharing a terminal. So what we do is to go through all
+ the saving and restoring of the tty state, but ignore errors
+ setting the process group, which will happen if we are not
+ sharing a terminal). */
+
+ if (job_control)
+ {
+#ifdef HAVE_TERMIOS
+ result = tcsetpgrp (0, inferior_process_group);
+ if (!attach_flag)
+ OOPSY ("tcsetpgrp");
+#endif
+
+#ifdef HAVE_SGTTY
+ result = ioctl (0, TIOCSPGRP, &inferior_process_group);
+ if (!attach_flag)
+ OOPSY ("TIOCSPGRP");
+#endif
+ }
+
+ }
+ terminal_is_ours = 0;
+}
+
+/* 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. */
+
+void
+terminal_ours_for_output ()
+{
+ terminal_ours_1 (1);
+}
+
+/* Put our terminal settings into effect.
+ First record the inferior's terminal settings
+ so they can be restored properly later. */
+
+void
+terminal_ours ()
+{
+ terminal_ours_1 (0);
+}
+
+/* output_only is not used, and should not be used unless we introduce
+ separate terminal_is_ours and terminal_is_ours_for_output
+ flags. */
+
+static void
+terminal_ours_1 (output_only)
+ int output_only;
+{
+ /* Checking inferior_thisrun_terminal is necessary so that
+ if GDB is running in the background, it won't block trying
+ to do the ioctl()'s below. Checking gdb_has_a_terminal
+ avoids attempting all the ioctl's when running in batch. */
+ if (inferior_thisrun_terminal != 0 || gdb_has_a_terminal () == 0)
+ return;
+
+ if (!terminal_is_ours)
+ {
+ /* Ignore this signal since it will happen when we try to set the
+ pgrp. */
+ void (*osigttou) ();
+ int result;
+
+ terminal_is_ours = 1;
+
+#ifdef SIGTTOU
+ if (job_control)
+ osigttou = (void (*) ()) signal (SIGTTOU, SIG_IGN);
+#endif
+
+ if (inferior_ttystate)
+ free (inferior_ttystate);
+ inferior_ttystate = SERIAL_GET_TTY_STATE (stdin_serial);
+#ifdef HAVE_TERMIOS
+ inferior_process_group = tcgetpgrp (0);
+#endif
+#ifdef HAVE_TERMIO
+ inferior_process_group = getpgrp ();
+#endif
+#ifdef HAVE_SGTTY
+ ioctl (0, TIOCGPGRP, &inferior_process_group);
+#endif
+
+ /* Here we used to set ICANON in our ttystate, but I believe this
+ was an artifact from before when we used readline. Readline sets
+ the tty state when it needs to.
+ FIXME-maybe: However, query() expects non-raw mode and doesn't
+ use readline. Maybe query should use readline (on the other hand,
+ this only matters for HAVE_SGTTY, not termio or termios, I think). */
+
+ /* Set tty state to our_ttystate. We don't change in our out of raw
+ mode, to avoid flushing input. We need to do the same thing
+ regardless of output_only, because we don't have separate
+ terminal_is_ours and terminal_is_ours_for_output flags. It's OK,
+ though, since readline will deal with raw mode when/if it needs to.
+ */
+
+ SERIAL_NOFLUSH_SET_TTY_STATE (stdin_serial, our_ttystate,
+ inferior_ttystate);
+
+ if (job_control)
+ {
+#ifdef HAVE_TERMIOS
+ result = tcsetpgrp (0, our_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 terminal_ours: %s]\n",
+ strerror (errno));
+#endif
+#endif /* termios */
+
+#ifdef HAVE_SGTTY
+ result = ioctl (0, TIOCSPGRP, &our_process_group);
+#endif
+ }
+
+#ifdef SIGTTOU
+ if (job_control)
+ signal (SIGTTOU, osigttou);
+#endif
+
+ if (!job_control)
+ {
+ signal (SIGINT, sigint_ours);
+#ifdef SIGQUIT
+ signal (SIGQUIT, sigquit_ours);
+#endif
+ }
+
+#ifdef F_GETFL
+ tflags_inferior = fcntl (0, F_GETFL, 0);
+
+ /* Is there a reason this is being done twice? It happens both
+ places we use F_SETFL, so I'm inclined to think perhaps there
+ is some reason, however perverse. Perhaps not though... */
+ result = fcntl (0, F_SETFL, tflags_ours);
+ result = fcntl (0, F_SETFL, tflags_ours);
+#endif
+
+ result = result; /* lint */
+ }
+}
+
+/* ARGSUSED */
+void
+term_info (arg, from_tty)
+ char *arg;
+ int from_tty;
+{
+ target_terminal_info (arg, from_tty);
+}
+
+/* ARGSUSED */
+void
+child_terminal_info (args, from_tty)
+ char *args;
+ int from_tty;
+{
+ if (!gdb_has_a_terminal ())
+ {
+ printf_filtered ("This GDB does not control a terminal.\n");
+ return;
+ }
+
+ printf_filtered ("Inferior's terminal status (currently saved by GDB):\n");
+
+ /* First the fcntl flags. */
+ {
+ int flags;
+
+ flags = tflags_inferior;
+
+ printf_filtered ("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: 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 (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
+
+ 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
+
+ if (flags)
+ printf_filtered (" | 0x%x", flags);
+ printf_filtered ("\n");
+ }
+
+#ifdef PROCESS_GROUP_TYPE
+ printf_filtered ("Process group = %d\n", inferior_process_group);
+#endif
+
+ SERIAL_PRINT_TTY_STATE (stdin_serial, inferior_ttystate);
+}
+
+/* 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 (ttyname)
+ char *ttyname;
+{
+ /* Save the name for later, for determining whether we and the child
+ are sharing a tty. */
+ inferior_thisrun_terminal = ttyname;
+}
+
+void
+new_tty ()
+{
+ register int tty;
+
+ if (inferior_thisrun_terminal == 0)
+ return;
+#if !defined(__GO32__) && !defined(_WIN32)
+#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)
+ {
+ void (*osigttou) ();
+
+ osigttou = (void (*)()) signal(SIGTTOU, SIG_IGN);
+ ioctl(tty, TIOCNOTTY, 0);
+ close(tty);
+ signal(SIGTTOU, osigttou);
+ }
+#endif
+
+ /* Now open the specified new terminal. */
+
+#ifdef USE_O_NOCTTY
+ tty = open(inferior_thisrun_terminal, O_RDWR | O_NOCTTY);
+#else
+ tty = open(inferior_thisrun_terminal, O_RDWR);
+#endif
+ if (tty == -1)
+ {
+ print_sys_errmsg (inferior_thisrun_terminal, errno);
+ _exit(1);
+ }
+
+ /* Avoid use of dup2; doesn't exist on all systems. */
+ if (tty != 0)
+ { close (0); dup (tty); }
+ if (tty != 1)
+ { close (1); dup (tty); }
+ if (tty != 2)
+ { close (2); dup (tty); }
+ if (tty > 2)
+ close(tty);
+#endif /* !go32 && !win32*/
+}
+
+/* Kill the inferior process. Make us have no inferior. */
+
+/* ARGSUSED */
+static void
+kill_command (arg, from_tty)
+ char *arg;
+ int from_tty;
+{
+ /* FIXME: This should not really be inferior_pid (or target_has_execution).
+ It should be a distinct flag that indicates that a target is active, cuz
+ some targets don't have processes! */
+
+ if (inferior_pid == 0)
+ error ("The program is not being run.");
+ if (!query ("Kill the program being debugged? "))
+ error ("Not confirmed.");
+ target_kill ();
+
+ init_thread_list(); /* Destroy thread info */
+
+ /* Killing off the inferior can leave us with a core file. If so,
+ print the state we are left in. */
+ if (target_has_stack) {
+ printf_filtered ("In %s,\n", target_longname);
+ if (selected_frame == NULL)
+ fputs_filtered ("No selected stack frame.\n", gdb_stdout);
+ else
+ print_stack_frame (selected_frame, selected_frame_level, 1);
+ }
+}
+
+/* Call set_sigint_trap when you need to pass a signal on to an attached
+ process when handling SIGINT */
+
+/* ARGSUSED */
+static void
+pass_signal (signo)
+ int signo;
+{
+#ifndef _WIN32
+ kill (PIDGET (inferior_pid), SIGINT);
+#endif
+}
+
+static void (*osig)();
+
+void
+set_sigint_trap()
+{
+ if (attach_flag || inferior_thisrun_terminal)
+ {
+ osig = (void (*) ()) signal (SIGINT, pass_signal);
+ }
+}
+
+void
+clear_sigint_trap()
+{
+ if (attach_flag || inferior_thisrun_terminal)
+ {
+ signal (SIGINT, osig);
+ }
+}
+
+#if defined (SIGIO) && defined (FASYNC) && defined (FD_SET) && defined (F_SETOWN)
+static void (*old_sigio) ();
+
+static void
+handle_sigio (signo)
+ int signo;
+{
+ int numfds;
+ fd_set readfds;
+
+ signal (SIGIO, handle_sigio);
+
+ FD_ZERO (&readfds);
+ FD_SET (target_activity_fd, &readfds);
+ numfds = select (target_activity_fd + 1, &readfds, NULL, NULL, NULL);
+ if (numfds >= 0 && FD_ISSET (target_activity_fd, &readfds))
+ {
+#ifndef _WIN32
+ if ((*target_activity_function) ())
+ kill (inferior_pid, SIGINT);
+#endif
+ }
+}
+
+static int old_fcntl_flags;
+
+void
+set_sigio_trap ()
+{
+ if (target_activity_function)
+ {
+ old_sigio = (void (*) ()) signal (SIGIO, handle_sigio);
+ fcntl (target_activity_fd, F_SETOWN, getpid());
+ old_fcntl_flags = fcntl (target_activity_fd, F_GETFL, 0);
+ fcntl (target_activity_fd, F_SETFL, old_fcntl_flags | FASYNC);
+ }
+}
+
+void
+clear_sigio_trap ()
+{
+ if (target_activity_function)
+ {
+ signal (SIGIO, old_sigio);
+ fcntl (target_activity_fd, F_SETFL, old_fcntl_flags);
+ }
+}
+#else /* No SIGIO. */
+void
+set_sigio_trap ()
+{
+ if (target_activity_function)
+ abort ();
+}
+
+void
+clear_sigio_trap ()
+{
+ if (target_activity_function)
+ abort ();
+}
+#endif /* No SIGIO. */
+
+
+/* This is here because this is where we figure out whether we (probably)
+ have job control. Just using job_control only does part of it because
+ setpgid or setpgrp might not exist on a system without job control.
+ It might be considered misplaced (on the other hand, process groups and
+ job control are closely related to ttys).
+
+ For a more clean implementation, in libiberty, put a setpgid which merely
+ calls setpgrp and a setpgrp which does nothing (any system with job control
+ will have one or the other). */
+int
+gdb_setpgid ()
+{
+ int retval = 0;
+
+ if (job_control)
+ {
+#if defined (NEED_POSIX_SETPGID) || (defined (HAVE_TERMIOS) && defined (HAVE_SETPGID))
+ /* setpgid (0, 0) is supposed to work and mean the same thing as
+ this, but on Ultrix 4.2A it fails with EPERM (and
+ setpgid (getpid (), getpid ()) succeeds). */
+ retval = setpgid (getpid (), getpid ());
+#else
+#if defined (TIOCGPGRP)
+#if defined(USG) && !defined(SETPGRP_ARGS)
+ retval = setpgrp ();
+#else
+ retval = setpgrp (getpid (), getpid ());
+#endif /* USG */
+#endif /* TIOCGPGRP. */
+#endif /* NEED_POSIX_SETPGID */
+ }
+ return retval;
+}
+
+void
+_initialize_inflow ()
+{
+ add_info ("terminal", term_info,
+ "Print inferior's saved terminal status.");
+
+ add_com ("kill", class_run, kill_command,
+ "Kill execution of program being debugged.");
+
+ inferior_pid = 0;
+
+ terminal_is_ours = 1;
+
+ /* OK, figure out whether we have job control. If neither termios nor
+ sgtty (i.e. termio or go32), leave job_control 0. */
+
+#if defined (HAVE_TERMIOS)
+ /* Do all systems with termios have the POSIX way of identifying job
+ control? I hope so. */
+#ifdef _POSIX_JOB_CONTROL
+ job_control = 1;
+#else
+#ifdef _SC_JOB_CONTROL
+ job_control = sysconf (_SC_JOB_CONTROL);
+#else
+ job_control = 0; /* have to assume the worst */
+#endif /* _SC_JOB_CONTROL */
+#endif /* _POSIX_JOB_CONTROL */
+#endif /* HAVE_TERMIOS */
+
+#ifdef HAVE_SGTTY
+#ifdef TIOCGPGRP
+ job_control = 1;
+#else
+ job_control = 0;
+#endif /* TIOCGPGRP */
+#endif /* sgtty */
+}