Esempio n. 1
0
void
startup_inferior (int ntraps)
{
  int pending_execs = ntraps;
  int terminal_initted = 0;
  ptid_t resume_ptid;

  if (target_supports_multi_process ())
    resume_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
  else
    resume_ptid = minus_one_ptid;

  /* The process was started by the fork that created it, but it will
     have stopped one instruction after execing the shell.  Here we
     must get it up to actual execution of the real program.  */

  if (exec_wrapper)
    pending_execs++;

  while (1)
    {
      enum gdb_signal resume_signal = GDB_SIGNAL_0;
      ptid_t event_ptid;

      struct target_waitstatus ws;
      memset (&ws, 0, sizeof (ws));
      event_ptid = target_wait (resume_ptid, &ws, 0);

      if (ws.kind == TARGET_WAITKIND_IGNORE)
	/* The inferior didn't really stop, keep waiting.  */
	continue;

      switch (ws.kind)
	{
	  case TARGET_WAITKIND_SPURIOUS:
	  case TARGET_WAITKIND_LOADED:
	  case TARGET_WAITKIND_FORKED:
	  case TARGET_WAITKIND_VFORKED:
	  case TARGET_WAITKIND_SYSCALL_ENTRY:
	  case TARGET_WAITKIND_SYSCALL_RETURN:
	    /* Ignore gracefully during startup of the inferior.  */
	    switch_to_thread (event_ptid);
	    break;

	  case TARGET_WAITKIND_SIGNALLED:
	    target_terminal_ours ();
	    target_mourn_inferior ();
	    error (_("During startup program terminated with signal %s, %s."),
		   gdb_signal_to_name (ws.value.sig),
		   gdb_signal_to_string (ws.value.sig));
	    return;

	  case TARGET_WAITKIND_EXITED:
	    target_terminal_ours ();
	    target_mourn_inferior ();
	    if (ws.value.integer)
	      error (_("During startup program exited with code %d."),
		     ws.value.integer);
	    else
	      error (_("During startup program exited normally."));
	    return;

	  case TARGET_WAITKIND_EXECD:
	    /* Handle EXEC signals as if they were SIGTRAP signals.  */
	    xfree (ws.value.execd_pathname);
	    resume_signal = GDB_SIGNAL_TRAP;
	    switch_to_thread (event_ptid);
	    break;

	  case TARGET_WAITKIND_STOPPED:
	    resume_signal = ws.value.sig;
	    switch_to_thread (event_ptid);
	    break;
	}

      if (resume_signal != GDB_SIGNAL_TRAP)
	{
	  /* Let shell child handle its own signals in its own way.  */
	  target_resume (resume_ptid, 0, resume_signal);
	}
      else
	{
	  /* We handle SIGTRAP, however; it means child did an exec.  */
	  if (!terminal_initted)
	    {
	      /* Now that the child has exec'd we know it has already
	         set its process group.  On POSIX systems, tcsetpgrp
	         will fail with EPERM if we try it before the child's
	         setpgid.  */

	      /* Set up the "saved terminal modes" of the inferior
	         based on what modes we are starting it with.  */
	      target_terminal_init ();

	      /* Install inferior's terminal modes.  */
	      target_terminal_inferior ();

	      terminal_initted = 1;
	    }

	  if (--pending_execs == 0)
	    break;

	  /* Just make it go on.  */
	  target_resume (resume_ptid, 0, GDB_SIGNAL_0);
	}
    }

  /* Mark all threads non-executing.  */
  set_executing (resume_ptid, 0);
}
Esempio n. 2
0
static void
core_open (char *filename, int from_tty)
{
  const char *p;
  int siggy;
  struct cleanup *old_chain;
  char *temp;
  bfd *temp_bfd;
  int scratch_chan;
  int flags;
  volatile struct gdb_exception except;

  target_preopen (from_tty);
  if (!filename)
    {
      if (core_bfd)
	error (_("No core file specified.  (Use `detach' "
		 "to stop debugging a core file.)"));
      else
	error (_("No core file specified."));
    }

  filename = tilde_expand (filename);
  if (!IS_ABSOLUTE_PATH (filename))
    {
      temp = concat (current_directory, "/",
		     filename, (char *) NULL);
      xfree (filename);
      filename = temp;
    }

  old_chain = make_cleanup (xfree, filename);

  flags = O_BINARY | O_LARGEFILE;
  if (write_files)
    flags |= O_RDWR;
  else
    flags |= O_RDONLY;
  scratch_chan = open (filename, flags, 0);
  if (scratch_chan < 0)
    perror_with_name (filename);

  temp_bfd = bfd_fopen (filename, gnutarget, 
			write_files ? FOPEN_RUB : FOPEN_RB,
			scratch_chan);
  if (temp_bfd == NULL)
    perror_with_name (filename);

  if (!bfd_check_format (temp_bfd, bfd_core)
      && !gdb_check_format (temp_bfd))
    {
      /* Do it after the err msg */
      /* FIXME: should be checking for errors from bfd_close (for one
         thing, on error it does not free all the storage associated
         with the bfd).  */
      make_cleanup_bfd_close (temp_bfd);
      error (_("\"%s\" is not a core dump: %s"),
	     filename, bfd_errmsg (bfd_get_error ()));
    }

  /* Looks semi-reasonable.  Toss the old core file and work on the
     new.  */

  discard_cleanups (old_chain);	/* Don't free filename any more */
  unpush_target (&core_ops);
  core_bfd = temp_bfd;
  old_chain = make_cleanup (core_close_cleanup, 0 /*ignore*/);

  /* FIXME: kettenis/20031023: This is very dangerous.  The
     CORE_GDBARCH that results from this call may very well be
     different from CURRENT_GDBARCH.  However, its methods may only
     work if it is selected as the current architecture, because they
     rely on swapped data (see gdbarch.c).  We should get rid of that
     swapped data.  */
  core_gdbarch = gdbarch_from_bfd (core_bfd);

  /* Find a suitable core file handler to munch on core_bfd */
  core_vec = sniff_core_bfd (core_bfd);

  validate_files ();

  core_data = XZALLOC (struct target_section_table);

  /* Find the data section */
  if (build_section_table (core_bfd,
			   &core_data->sections,
			   &core_data->sections_end))
    error (_("\"%s\": Can't find sections: %s"),
	   bfd_get_filename (core_bfd), bfd_errmsg (bfd_get_error ()));

  /* If we have no exec file, try to set the architecture from the
     core file.  We don't do this unconditionally since an exec file
     typically contains more information that helps us determine the
     architecture than a core file.  */
  if (!exec_bfd)
    set_gdbarch_from_file (core_bfd);

  push_target (&core_ops);
  discard_cleanups (old_chain);

  /* Do this before acknowledging the inferior, so if
     post_create_inferior throws (can happen easilly if you're loading
     a core file with the wrong exec), we aren't left with threads
     from the previous inferior.  */
  init_thread_list ();

  inferior_ptid = null_ptid;

  /* Need to flush the register cache (and the frame cache) from a
     previous debug session.  If inferior_ptid ends up the same as the
     last debug session --- e.g., b foo; run; gcore core1; step; gcore
     core2; core core1; core core2 --- then there's potential for
     get_current_regcache to return the cached regcache of the
     previous session, and the frame cache being stale.  */
  registers_changed ();

  /* Build up thread list from BFD sections, and possibly set the
     current thread to the .reg/NN section matching the .reg
     section.  */
  bfd_map_over_sections (core_bfd, add_to_thread_list,
			 bfd_get_section_by_name (core_bfd, ".reg"));

  if (ptid_equal (inferior_ptid, null_ptid))
    {
      /* Either we found no .reg/NN section, and hence we have a
	 non-threaded core (single-threaded, from gdb's perspective),
	 or for some reason add_to_thread_list couldn't determine
	 which was the "main" thread.  The latter case shouldn't
	 usually happen, but we're dealing with input here, which can
	 always be broken in different ways.  */
      struct thread_info *thread = first_thread_of_process (-1);

      if (thread == NULL)
	{
	  inferior_appeared (current_inferior (), CORELOW_PID);
	  inferior_ptid = pid_to_ptid (CORELOW_PID);
	  add_thread_silent (inferior_ptid);
	}
      else
	switch_to_thread (thread->ptid);
    }

  post_create_inferior (&core_ops, from_tty);

  /* Now go through the target stack looking for threads since there
     may be a thread_stratum target loaded on top of target core by
     now.  The layer above should claim threads found in the BFD
     sections.  */
  TRY_CATCH (except, RETURN_MASK_ERROR)
    {
      target_find_new_threads ();
    }

  if (except.reason < 0)
    exception_print (gdb_stderr, except);

  p = bfd_core_file_failing_command (core_bfd);
  if (p)
    printf_filtered (_("Core was generated by `%s'.\n"), p);

  siggy = bfd_core_file_failing_signal (core_bfd);
  if (siggy > 0)
    {
      /* If we don't have a CORE_GDBARCH to work with, assume a native
	 core (map gdb_signal from host signals).  If we do have
	 CORE_GDBARCH to work with, but no gdb_signal_from_target
	 implementation for that gdbarch, as a fallback measure,
	 assume the host signal mapping.  It'll be correct for native
	 cores, but most likely incorrect for cross-cores.  */
      enum gdb_signal sig = (core_gdbarch != NULL
			     && gdbarch_gdb_signal_from_target_p (core_gdbarch)
			     ? gdbarch_gdb_signal_from_target (core_gdbarch,
							       siggy)
			     : gdb_signal_from_host (siggy));

      printf_filtered (_("Program terminated with signal %d, %s.\n"),
		       siggy, gdb_signal_to_string (sig));
    }

  /* Fetch all registers from core file.  */
  target_fetch_registers (get_current_regcache (), -1);

  /* Now, set up the frame cache, and print the top of stack.  */
  reinit_frame_cache ();
  print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC);
}
Esempio n. 3
0
void
core_target_open (const char *arg, int from_tty)
{
  const char *p;
  int siggy;
  int scratch_chan;
  int flags;

  target_preopen (from_tty);
  if (!arg)
    {
      if (core_bfd)
	error (_("No core file specified.  (Use `detach' "
		 "to stop debugging a core file.)"));
      else
	error (_("No core file specified."));
    }

  gdb::unique_xmalloc_ptr<char> filename (tilde_expand (arg));
  if (!IS_ABSOLUTE_PATH (filename.get ()))
    filename.reset (concat (current_directory, "/",
			    filename.get (), (char *) NULL));

  flags = O_BINARY | O_LARGEFILE;
  if (write_files)
    flags |= O_RDWR;
  else
    flags |= O_RDONLY;
  scratch_chan = gdb_open_cloexec (filename.get (), flags, 0);
  if (scratch_chan < 0)
    perror_with_name (filename.get ());

  gdb_bfd_ref_ptr temp_bfd (gdb_bfd_fopen (filename.get (), gnutarget,
					   write_files ? FOPEN_RUB : FOPEN_RB,
					   scratch_chan));
  if (temp_bfd == NULL)
    perror_with_name (filename.get ());

  if (!bfd_check_format (temp_bfd.get (), bfd_core)
      && !gdb_check_format (temp_bfd.get ()))
    {
      /* Do it after the err msg */
      /* FIXME: should be checking for errors from bfd_close (for one
         thing, on error it does not free all the storage associated
         with the bfd).  */
      error (_("\"%s\" is not a core dump: %s"),
	     filename.get (), bfd_errmsg (bfd_get_error ()));
    }

  current_program_space->cbfd = std::move (temp_bfd);

  core_target *target = new core_target ();

  /* Own the target until it is successfully pushed.  */
  target_ops_up target_holder (target);

  validate_files ();

  /* If we have no exec file, try to set the architecture from the
     core file.  We don't do this unconditionally since an exec file
     typically contains more information that helps us determine the
     architecture than a core file.  */
  if (!exec_bfd)
    set_gdbarch_from_file (core_bfd);

  push_target (std::move (target_holder));

  inferior_ptid = null_ptid;

  /* Need to flush the register cache (and the frame cache) from a
     previous debug session.  If inferior_ptid ends up the same as the
     last debug session --- e.g., b foo; run; gcore core1; step; gcore
     core2; core core1; core core2 --- then there's potential for
     get_current_regcache to return the cached regcache of the
     previous session, and the frame cache being stale.  */
  registers_changed ();

  /* Build up thread list from BFD sections, and possibly set the
     current thread to the .reg/NN section matching the .reg
     section.  */
  bfd_map_over_sections (core_bfd, add_to_thread_list,
			 bfd_get_section_by_name (core_bfd, ".reg"));

  if (inferior_ptid == null_ptid)
    {
      /* Either we found no .reg/NN section, and hence we have a
	 non-threaded core (single-threaded, from gdb's perspective),
	 or for some reason add_to_thread_list couldn't determine
	 which was the "main" thread.  The latter case shouldn't
	 usually happen, but we're dealing with input here, which can
	 always be broken in different ways.  */
      thread_info *thread = first_thread_of_inferior (current_inferior ());

      if (thread == NULL)
	{
	  inferior_appeared (current_inferior (), CORELOW_PID);
	  inferior_ptid = ptid_t (CORELOW_PID);
	  add_thread_silent (inferior_ptid);
	}
      else
	switch_to_thread (thread);
    }

  post_create_inferior (target, from_tty);

  /* Now go through the target stack looking for threads since there
     may be a thread_stratum target loaded on top of target core by
     now.  The layer above should claim threads found in the BFD
     sections.  */
  try
    {
      target_update_thread_list ();
    }

  catch (const gdb_exception_error &except)
    {
      exception_print (gdb_stderr, except);
    }

  p = bfd_core_file_failing_command (core_bfd);
  if (p)
    printf_filtered (_("Core was generated by `%s'.\n"), p);

  /* Clearing any previous state of convenience variables.  */
  clear_exit_convenience_vars ();

  siggy = bfd_core_file_failing_signal (core_bfd);
  if (siggy > 0)
    {
      gdbarch *core_gdbarch = target->core_gdbarch ();

      /* If we don't have a CORE_GDBARCH to work with, assume a native
	 core (map gdb_signal from host signals).  If we do have
	 CORE_GDBARCH to work with, but no gdb_signal_from_target
	 implementation for that gdbarch, as a fallback measure,
	 assume the host signal mapping.  It'll be correct for native
	 cores, but most likely incorrect for cross-cores.  */
      enum gdb_signal sig = (core_gdbarch != NULL
			     && gdbarch_gdb_signal_from_target_p (core_gdbarch)
			     ? gdbarch_gdb_signal_from_target (core_gdbarch,
							       siggy)
			     : gdb_signal_from_host (siggy));

      printf_filtered (_("Program terminated with signal %s, %s.\n"),
		       gdb_signal_to_name (sig), gdb_signal_to_string (sig));

      /* Set the value of the internal variable $_exitsignal,
	 which holds the signal uncaught by the inferior.  */
      set_internalvar_integer (lookup_internalvar ("_exitsignal"),
			       siggy);
    }

  /* Fetch all registers from core file.  */
  target_fetch_registers (get_current_regcache (), -1);

  /* Now, set up the frame cache, and print the top of stack.  */
  reinit_frame_cache ();
  print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC, 1);

  /* Current thread should be NUM 1 but the user does not know that.
     If a program is single threaded gdb in general does not mention
     anything about threads.  That is why the test is >= 2.  */
  if (thread_count () >= 2)
    {
      try
	{
	  thread_command (NULL, from_tty);
	}
      catch (const gdb_exception_error &except)
	{
	  exception_print (gdb_stderr, except);
	}
    }
}