Subversion Repositories openrisc_2011-10-31

/* Top level stuff for GDB, the GNU debugger.

   Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,

   1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,

   2008, 2009, 2010 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 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 "gdbcmd.h"

#include "call-cmds.h"

#include "cli/cli-cmds.h"

#include "cli/cli-script.h"

#include "cli/cli-setshow.h"

#include "cli/cli-decode.h"

#include "symtab.h"

#include "inferior.h"

#include "exceptions.h"

#include <signal.h>

#include "target.h"

#include "breakpoint.h"

#include "gdbtypes.h"

#include "expression.h"

#include "value.h"

#include "language.h"

#include "terminal.h"           /* For job_control.  */

#include "annotate.h"

#include "completer.h"

#include "top.h"

#include "version.h"

#include "serial.h"

#include "doublest.h"

#include "gdb_assert.h"

#include "main.h"

#include "event-loop.h"

#include "gdbthread.h"

/* readline include files */

#include "readline/readline.h"

#include "readline/history.h"

/* readline defines this.  */

#undef savestring

#include <sys/types.h>

#include "event-top.h"

#include "gdb_string.h"

#include "gdb_stat.h"

#include <ctype.h>

#include "ui-out.h"

#include "cli-out.h"

/* Default command line prompt.  This is overriden in some configs. */

#ifndef DEFAULT_PROMPT

#define DEFAULT_PROMPT  "(gdb) "

#endif

/* Initialization file name for gdb.  This is overridden in some configs.  */

#ifndef PATH_MAX

# ifdef FILENAME_MAX

#  define PATH_MAX FILENAME_MAX

# else

#  define PATH_MAX 512

# endif

#endif

#ifndef GDBINIT_FILENAME

#define GDBINIT_FILENAME        ".gdbinit"

#endif

char gdbinit[PATH_MAX + 1] = GDBINIT_FILENAME;

int inhibit_gdbinit = 0;

/* If nonzero, and GDB has been configured to be able to use windows,

   attempt to open them upon startup.  */

int use_windows = 0;

extern char lang_frame_mismatch_warn[];         /* language.c */

/* Flag for whether we want all the "from_tty" gubbish printed.  */

int caution = 1;                /* Default is yes, sigh. */

static void

show_caution (struct ui_file *file, int from_tty,

              struct cmd_list_element *c, const char *value)

{

  fprintf_filtered (file, _("\

Whether to confirm potentially dangerous operations is %s.\n"),

                    value);

}

/* stdio stream that command input is being read from.  Set to stdin normally.

   Set by source_command to the file we are sourcing.  Set to NULL if we are

   executing a user-defined command or interacting via a GUI.  */

FILE *instream;

/* Flag to indicate whether a user defined command is currently running.  */

int in_user_command;

/* Current working directory.  */

char *current_directory;

/* The directory name is actually stored here (usually).  */

char gdb_dirbuf[1024];

/* Function to call before reading a command, if nonzero.

   The function receives two args: an input stream,

   and a prompt string.  */

void (*window_hook) (FILE *, char *);

int epoch_interface;

int xgdb_verbose;

/* Buffer used for reading command lines, and the size

   allocated for it so far.  */

char *line;

int linesize = 100;

/* Nonzero if the current command is modified by "server ".  This

   affects things like recording into the command history, commands

   repeating on RETURN, etc.  This is so a user interface (emacs, GUI,

   whatever) can issue its own commands and also send along commands

   from the user, and have the user not notice that the user interface

   is issuing commands too.  */

int server_command;

/* Baud rate specified for talking to serial target systems.  Default

   is left as -1, so targets can choose their own defaults.  */

/* FIXME: This means that "show remotebaud" and gr_files_info can print -1

   or (unsigned int)-1.  This is a Bad User Interface.  */

int baud_rate = -1;

/* Timeout limit for response from target. */

/* The default value has been changed many times over the years.  It

   was originally 5 seconds.  But that was thought to be a long time

   to sit and wait, so it was changed to 2 seconds.  That was thought

   to be plenty unless the connection was going through some terminal

   server or multiplexer or other form of hairy serial connection.

   In mid-1996, remote_timeout was moved from remote.c to top.c and

   it began being used in other remote-* targets.  It appears that the

   default was changed to 20 seconds at that time, perhaps because the

   Renesas E7000 ICE didn't always respond in a timely manner.

   But if 5 seconds is a long time to sit and wait for retransmissions,

   20 seconds is far worse.  This demonstrates the difficulty of using

   a single variable for all protocol timeouts.

   As remote.c is used much more than remote-e7000.c, it was changed

   back to 2 seconds in 1999. */

int remote_timeout = 2;

/* Non-zero tells remote* modules to output debugging info.  */

int remote_debug = 0;

/* Sbrk location on entry to main.  Used for statistics only.  */

#ifdef HAVE_SBRK

char *lim_at_start;

#endif

/* Hooks for alternate command interfaces.  */

/* Called after most modules have been initialized, but before taking users

   command file.

   If the UI fails to initialize and it wants GDB to continue

   using the default UI, then it should clear this hook before returning. */

void (*deprecated_init_ui_hook) (char *argv0);

/* This hook is called from within gdb's many mini-event loops which could

   steal control from a real user interface's event loop. It returns

   non-zero if the user is requesting a detach, zero otherwise. */

int (*deprecated_ui_loop_hook) (int);

/* Called instead of command_loop at top level.  Can be invoked via

   throw_exception().  */

void (*deprecated_command_loop_hook) (void);

/* Called from print_frame_info to list the line we stopped in.  */

void (*deprecated_print_frame_info_listing_hook) (struct symtab * s, int line,

                                                  int stopline, int noerror);

/* Replaces most of query.  */

int (*deprecated_query_hook) (const char *, va_list);

/* Replaces most of warning.  */

void (*deprecated_warning_hook) (const char *, va_list);

/* These three functions support getting lines of text from the user.

   They are used in sequence.  First deprecated_readline_begin_hook is

   called with a text string that might be (for example) a message for

   the user to type in a sequence of commands to be executed at a

   breakpoint.  If this function calls back to a GUI, it might take

   this opportunity to pop up a text interaction window with this

   message.  Next, deprecated_readline_hook is called with a prompt

   that is emitted prior to collecting the user input.  It can be

   called multiple times.  Finally, deprecated_readline_end_hook is

   called to notify the GUI that we are done with the interaction

   window and it can close it.  */

void (*deprecated_readline_begin_hook) (char *, ...);

char *(*deprecated_readline_hook) (char *);

void (*deprecated_readline_end_hook) (void);

/* Called as appropriate to notify the interface that we have attached

   to or detached from an already running process. */

void (*deprecated_attach_hook) (void);

void (*deprecated_detach_hook) (void);

/* Called during long calculations to allow GUI to repair window damage, and to

   check for stop buttons, etc... */

void (*deprecated_interactive_hook) (void);

/* Tell the GUI someone changed the register REGNO. -1 means

   that the caller does not know which register changed or

   that several registers have changed (see value_assign). */

void (*deprecated_register_changed_hook) (int regno);

/* Called when going to wait for the target.  Usually allows the GUI to run

   while waiting for target events.  */

ptid_t (*deprecated_target_wait_hook) (ptid_t ptid,

                                       struct target_waitstatus *status,

                                       int options);

/* Used by UI as a wrapper around command execution.  May do various things

   like enabling/disabling buttons, etc...  */

void (*deprecated_call_command_hook) (struct cmd_list_element * c, char *cmd,

                                      int from_tty);

/* Called after a `set' command has finished.  Is only run if the

   `set' command succeeded.  */

void (*deprecated_set_hook) (struct cmd_list_element * c);

/* Called when the current thread changes.  Argument is thread id.  */

void (*deprecated_context_hook) (int id);

/* Handler for SIGHUP.  */

#ifdef SIGHUP

/* NOTE 1999-04-29: This function will be static again, once we modify

   gdb to use the event loop as the default command loop and we merge

   event-top.c into this file, top.c */

/* static */ int

quit_cover (void *s)

{

  caution = 0;                   /* Throw caution to the wind -- we're exiting.

                                   This prevents asking the user dumb questions.  */

  quit_command ((char *) 0, 0);

  return 0;

}

#endif /* defined SIGHUP */

/* Line number we are currently in in a file which is being sourced.  */

/* NOTE 1999-04-29: This variable will be static again, once we modify

   gdb to use the event loop as the default command loop and we merge

   event-top.c into this file, top.c */

/* static */ int source_line_number;

/* Name of the file we are sourcing.  */

/* NOTE 1999-04-29: This variable will be static again, once we modify

   gdb to use the event loop as the default command loop and we merge

   event-top.c into this file, top.c */

/* static */ char *source_file_name;

/* Clean up on error during a "source" command (or execution of a

   user-defined command).  */

void

do_restore_instream_cleanup (void *stream)

{

  /* Restore the previous input stream.  */

  instream = stream;

}

/* Read commands from STREAM.  */

void

read_command_file (FILE *stream)

{

  struct cleanup *cleanups;

  cleanups = make_cleanup (do_restore_instream_cleanup, instream);

  instream = stream;

  command_loop ();

  do_cleanups (cleanups);

}

void (*pre_init_ui_hook) (void);

#ifdef __MSDOS__

void

do_chdir_cleanup (void *old_dir)

{

  chdir (old_dir);

  xfree (old_dir);

}

#endif

void

prepare_execute_command (void)

{

  free_all_values ();

  /* With multiple threads running while the one we're examining is stopped,

     the dcache can get stale without us being able to detect it.

     For the duration of the command, though, use the dcache to help

     things like backtrace.  */

  if (non_stop)

    target_dcache_invalidate ();

}

/* Execute the line P as a command, in the current user context.

   Pass FROM_TTY as second argument to the defining function.  */

void

execute_command (char *p, int from_tty)

{

  struct cmd_list_element *c;

  enum language flang;

  static int warned = 0;

  char *line;

  long time_at_cmd_start = 0;

#ifdef HAVE_SBRK

  long space_at_cmd_start = 0;

#endif

  extern int display_time;

  extern int display_space;

  if (target_can_async_p ())

    {

      time_at_cmd_start = get_run_time ();

      if (display_space)

        {

#ifdef HAVE_SBRK

          char *lim = (char *) sbrk (0);

          space_at_cmd_start = lim - lim_at_start;

#endif

        }

    }

  prepare_execute_command ();

  /* Force cleanup of any alloca areas if using C alloca instead of

     a builtin alloca.  */

  alloca (0);

  /* This can happen when command_line_input hits end of file.  */

  if (p == NULL)

    return;

  target_log_command (p);

  while (*p == ' ' || *p == '\t')

    p++;

  if (*p)

    {

      char *arg;

      line = p;

      /* If trace-commands is set then this will print this command.  */

      print_command_trace (p);

      c = lookup_cmd (&p, cmdlist, "", 0, 1);

      /* Pass null arg rather than an empty one.  */

      arg = *p ? p : 0;

      /* FIXME: cagney/2002-02-02: The c->type test is pretty dodgy

         while the is_complete_command(cfunc) test is just plain

         bogus.  They should both be replaced by a test of the form

         c->strip_trailing_white_space_p.  */

      /* NOTE: cagney/2002-02-02: The function.cfunc in the below

         can't be replaced with func.  This is because it is the

         cfunc, and not the func, that has the value that the

         is_complete_command hack is testing for.  */

      /* Clear off trailing whitespace, except for set and complete

         command.  */

      if (arg

          && c->type != set_cmd

          && !is_complete_command (c))

        {

          p = arg + strlen (arg) - 1;

          while (p >= arg && (*p == ' ' || *p == '\t'))

            p--;

          *(p + 1) = '\0';

        }

      /* If this command has been pre-hooked, run the hook first. */

      execute_cmd_pre_hook (c);

      if (c->flags & DEPRECATED_WARN_USER)

        deprecated_cmd_warning (&line);

      if (c->class == class_user)

        execute_user_command (c, arg);

      else if (c->type == set_cmd || c->type == show_cmd)

        do_setshow_command (arg, from_tty & caution, c);

      else if (!cmd_func_p (c))

        error (_("That is not a command, just a help topic."));

      else if (deprecated_call_command_hook)

        deprecated_call_command_hook (c, arg, from_tty & caution);

      else

        cmd_func (c, arg, from_tty & caution);

      /* If this command has been post-hooked, run the hook last. */

      execute_cmd_post_hook (c);

    }

  /* Tell the user if the language has changed (except first time).

     First make sure that a new frame has been selected, in case this

     command or the hooks changed the program state.  */

  deprecated_safe_get_selected_frame ();

  if (current_language != expected_language)

    {

      if (language_mode == language_mode_auto && info_verbose)

        {

          language_info (1);    /* Print what changed.  */

        }

      warned = 0;

    }

  /* Warn the user if the working language does not match the

     language of the current frame.  Only warn the user if we are

     actually running the program, i.e. there is a stack. */

  /* FIXME:  This should be cacheing the frame and only running when

     the frame changes.  */

  if (has_stack_frames ())

    {

      flang = get_frame_language ();

      if (!warned

          && flang != language_unknown

          && flang != current_language->la_language)

        {

          printf_filtered ("%s\n", lang_frame_mismatch_warn);

          warned = 1;

        }

    }

}

/* Read commands from `instream' and execute them

   until end of file or error reading instream.  */

void

command_loop (void)

{

  struct cleanup *old_chain;

  char *command;

  int stdin_is_tty = ISATTY (stdin);

  long time_at_cmd_start;

#ifdef HAVE_SBRK

  long space_at_cmd_start = 0;

#endif

  extern int display_time;

  extern int display_space;

  while (instream && !feof (instream))

    {

      if (window_hook && instream == stdin)

        (*window_hook) (instream, get_prompt ());

      quit_flag = 0;

      if (instream == stdin && stdin_is_tty)

        reinitialize_more_filter ();

      old_chain = make_cleanup (null_cleanup, 0);

      /* Get a command-line. This calls the readline package. */

      command = command_line_input (instream == stdin ?

                                    get_prompt () : (char *) NULL,

                                    instream == stdin, "prompt");

      if (command == 0)

        return;

      time_at_cmd_start = get_run_time ();

      if (display_space)

        {

#ifdef HAVE_SBRK

          char *lim = (char *) sbrk (0);

          space_at_cmd_start = lim - lim_at_start;

#endif

        }

      execute_command (command, instream == stdin);

      /* Do any commands attached to breakpoint we are stopped at.  */

      bpstat_do_actions ();

      do_cleanups (old_chain);

      if (display_time)

        {

          long cmd_time = get_run_time () - time_at_cmd_start;

          printf_unfiltered (_("Command execution time: %ld.%06ld\n"),

                             cmd_time / 1000000, cmd_time % 1000000);

        }

      if (display_space)

        {

#ifdef HAVE_SBRK

          char *lim = (char *) sbrk (0);

          long space_now = lim - lim_at_start;

          long space_diff = space_now - space_at_cmd_start;

          printf_unfiltered (_("Space used: %ld (%s%ld for this command)\n"),

                             space_now,

                             (space_diff >= 0 ? "+" : ""),

                             space_diff);

#endif

        }

    }

}

/* Commands call this if they do not want to be repeated by null lines.  */

void

dont_repeat (void)

{

  if (server_command)

    return;

  /* If we aren't reading from standard input, we are saving the last

     thing read from stdin in line and don't want to delete it.  Null lines

     won't repeat here in any case.  */

  if (instream == stdin)

    *line = 0;

}

/* Read a line from the stream "instream" without command line editing.

   It prints PROMPT_ARG once at the start.

   Action is compatible with "readline", e.g. space for the result is

   malloc'd and should be freed by the caller.

   A NULL return means end of file.  */

char *

gdb_readline (char *prompt_arg)

{

  int c;

  char *result;

  int input_index = 0;

  int result_size = 80;

  if (prompt_arg)

    {

      /* Don't use a _filtered function here.  It causes the assumed

         character position to be off, since the newline we read from

         the user is not accounted for.  */

      fputs_unfiltered (prompt_arg, gdb_stdout);

      gdb_flush (gdb_stdout);

    }

  result = (char *) xmalloc (result_size);

  while (1)

    {

      /* Read from stdin if we are executing a user defined command.

         This is the right thing for prompt_for_continue, at least.  */

      c = fgetc (instream ? instream : stdin);

      if (c == EOF)

        {

          if (input_index > 0)

            /* The last line does not end with a newline.  Return it, and

               if we are called again fgetc will still return EOF and

               we'll return NULL then.  */

            break;

          xfree (result);

          return NULL;

        }

      if (c == '\n')

        {

          if (input_index > 0 && result[input_index - 1] == '\r')

            input_index--;

          break;

        }

      result[input_index++] = c;

      while (input_index >= result_size)

        {

          result_size *= 2;

          result = (char *) xrealloc (result, result_size);

        }

    }

  result[input_index++] = '\0';

  return result;

}

/* Variables which control command line editing and history

   substitution.  These variables are given default values at the end

   of this file.  */

static int command_editing_p;

/* NOTE 1999-04-29: This variable will be static again, once we modify

   gdb to use the event loop as the default command loop and we merge

   event-top.c into this file, top.c */

/* static */ int history_expansion_p;

static int write_history_p;

static void

show_write_history_p (struct ui_file *file, int from_tty,

                      struct cmd_list_element *c, const char *value)

{

  fprintf_filtered (file, _("Saving of the history record on exit is %s.\n"),

                    value);

}

static int history_size;

static void

show_history_size (struct ui_file *file, int from_tty,

                   struct cmd_list_element *c, const char *value)

{

  fprintf_filtered (file, _("The size of the command history is %s.\n"),

                    value);

}

static char *history_filename;

static void

show_history_filename (struct ui_file *file, int from_tty,

                       struct cmd_list_element *c, const char *value)

{

  fprintf_filtered (file, _("\

The filename in which to record the command history is \"%s\".\n"),

                    value);

}

/* This is like readline(), but it has some gdb-specific behavior.

   gdb may want readline in both the synchronous and async modes during

   a single gdb invocation.  At the ordinary top-level prompt we might

   be using the async readline.  That means we can't use

   rl_pre_input_hook, since it doesn't work properly in async mode.

   However, for a secondary prompt (" >", such as occurs during a

   `define'), gdb wants a synchronous response.

   We used to call readline() directly, running it in synchronous

   mode.  But mixing modes this way is not supported, and as of

   readline 5.x it no longer works; the arrow keys come unbound during

   the synchronous call.  So we make a nested call into the event

   loop.  That's what gdb_readline_wrapper is for.  */

/* A flag set as soon as gdb_readline_wrapper_line is called; we can't

   rely on gdb_readline_wrapper_result, which might still be NULL if

   the user types Control-D for EOF.  */

static int gdb_readline_wrapper_done;

/* The result of the current call to gdb_readline_wrapper, once a newline

   is seen.  */

static char *gdb_readline_wrapper_result;

/* Any intercepted hook.  Operate-and-get-next sets this, expecting it

   to be called after the newline is processed (which will redisplay

   the prompt).  But in gdb_readline_wrapper we will not get a new

   prompt until the next call, or until we return to the event loop.

   So we disable this hook around the newline and restore it before we

   return.  */

static void (*saved_after_char_processing_hook) (void);

/* This function is called when readline has seen a complete line of

   text.  */

static void

gdb_readline_wrapper_line (char *line)

{

  gdb_assert (!gdb_readline_wrapper_done);

  gdb_readline_wrapper_result = line;

  gdb_readline_wrapper_done = 1;

  /* Prevent operate-and-get-next from acting too early.  */

  saved_after_char_processing_hook = after_char_processing_hook;

  after_char_processing_hook = NULL;

  /* Prevent parts of the prompt from being redisplayed if annotations

     are enabled, and readline's state getting out of sync.  */

  if (async_command_editing_p)

    rl_callback_handler_remove ();

}

struct gdb_readline_wrapper_cleanup

  {

    void (*handler_orig) (char *);

    int already_prompted_orig;

  };

static void

gdb_readline_wrapper_cleanup (void *arg)

{

  struct gdb_readline_wrapper_cleanup *cleanup = arg;

  rl_already_prompted = cleanup->already_prompted_orig;

  gdb_assert (input_handler == gdb_readline_wrapper_line);

  input_handler = cleanup->handler_orig;

  gdb_readline_wrapper_result = NULL;

  gdb_readline_wrapper_done = 0;

  after_char_processing_hook = saved_after_char_processing_hook;

  saved_after_char_processing_hook = NULL;

  xfree (cleanup);

}

char *

gdb_readline_wrapper (char *prompt)

{