Initial creation of sourceware repositorygdb-4_18-branchpoint

1 files changed, 751 insertions, 0 deletions

diff --git a/gdb/inflow.c b/gdb/inflow.c
new file mode 100644
index 0000000..9033675
--- /dev/null
+++ b/gdb/inflow.c
@@ -0,0 +1,751 @@
+/* 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 */
+}