xref: /dragonfly/contrib/gdb-7/gdb/top.c (revision 279dd846)
1 /* Top level stuff for GDB, the GNU debugger.
2 
3    Copyright (C) 1986-2013 Free Software Foundation, Inc.
4 
5    This file is part of GDB.
6 
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 3 of the License, or
10    (at your option) any later version.
11 
12    This program is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16 
17    You should have received a copy of the GNU General Public License
18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
19 
20 #include "defs.h"
21 #include "gdbcmd.h"
22 #include "cli/cli-cmds.h"
23 #include "cli/cli-script.h"
24 #include "cli/cli-setshow.h"
25 #include "cli/cli-decode.h"
26 #include "symtab.h"
27 #include "inferior.h"
28 #include "exceptions.h"
29 #include <signal.h>
30 #include "target.h"
31 #include "breakpoint.h"
32 #include "gdbtypes.h"
33 #include "expression.h"
34 #include "value.h"
35 #include "language.h"
36 #include "terminal.h"		/* For job_control.  */
37 #include "annotate.h"
38 #include "completer.h"
39 #include "top.h"
40 #include "version.h"
41 #include "serial.h"
42 #include "doublest.h"
43 #include "gdb_assert.h"
44 #include "main.h"
45 #include "event-loop.h"
46 #include "gdbthread.h"
47 #include "python/python.h"
48 #include "interps.h"
49 #include "observer.h"
50 
51 /* readline include files.  */
52 #include "readline/readline.h"
53 #include "readline/history.h"
54 
55 /* readline defines this.  */
56 #undef savestring
57 
58 #include <sys/types.h>
59 
60 #include "event-top.h"
61 #include "gdb_string.h"
62 #include "gdb_stat.h"
63 #include <ctype.h>
64 #include "ui-out.h"
65 #include "cli-out.h"
66 
67 extern void initialize_all_files (void);
68 
69 #define PROMPT(X) the_prompts.prompt_stack[the_prompts.top + X].prompt
70 #define PREFIX(X) the_prompts.prompt_stack[the_prompts.top + X].prefix
71 #define SUFFIX(X) the_prompts.prompt_stack[the_prompts.top + X].suffix
72 
73 /* Default command line prompt.  This is overriden in some configs.  */
74 
75 #ifndef DEFAULT_PROMPT
76 #define DEFAULT_PROMPT	"(gdb) "
77 #endif
78 
79 /* Initialization file name for gdb.  This is overridden in some configs.  */
80 
81 #ifndef PATH_MAX
82 # ifdef FILENAME_MAX
83 #  define PATH_MAX FILENAME_MAX
84 # else
85 #  define PATH_MAX 512
86 # endif
87 #endif
88 
89 #ifndef	GDBINIT_FILENAME
90 #define	GDBINIT_FILENAME	".gdbinit"
91 #endif
92 char gdbinit[PATH_MAX + 1] = GDBINIT_FILENAME;
93 
94 int inhibit_gdbinit = 0;
95 
96 /* If nonzero, and GDB has been configured to be able to use windows,
97    attempt to open them upon startup.  */
98 
99 int use_windows = 0;
100 
101 extern char lang_frame_mismatch_warn[];		/* language.c */
102 
103 /* Flag for whether we want to confirm potentially dangerous
104    operations.  Default is yes.  */
105 
106 int confirm = 1;
107 
108 static void
109 show_confirm (struct ui_file *file, int from_tty,
110 	      struct cmd_list_element *c, const char *value)
111 {
112   fprintf_filtered (file, _("Whether to confirm potentially "
113 			    "dangerous operations is %s.\n"),
114 		    value);
115 }
116 
117 /* stdio stream that command input is being read from.  Set to stdin
118    normally.  Set by source_command to the file we are sourcing.  Set
119    to NULL if we are executing a user-defined command or interacting
120    via a GUI.  */
121 
122 FILE *instream;
123 
124 /* Flag to indicate whether a user defined command is currently running.  */
125 
126 int in_user_command;
127 
128 /* Current working directory.  */
129 
130 char *current_directory;
131 
132 /* The directory name is actually stored here (usually).  */
133 char gdb_dirbuf[1024];
134 
135 /* Function to call before reading a command, if nonzero.
136    The function receives two args: an input stream,
137    and a prompt string.  */
138 
139 void (*window_hook) (FILE *, char *);
140 
141 /* Buffer used for reading command lines, and the size
142    allocated for it so far.  */
143 
144 char *saved_command_line;
145 int saved_command_line_size = 100;
146 
147 /* Nonzero if the current command is modified by "server ".  This
148    affects things like recording into the command history, commands
149    repeating on RETURN, etc.  This is so a user interface (emacs, GUI,
150    whatever) can issue its own commands and also send along commands
151    from the user, and have the user not notice that the user interface
152    is issuing commands too.  */
153 int server_command;
154 
155 /* Baud rate specified for talking to serial target systems.  Default
156    is left as -1, so targets can choose their own defaults.  */
157 /* FIXME: This means that "show remotebaud" and gr_files_info can
158    print -1 or (unsigned int)-1.  This is a Bad User Interface.  */
159 
160 int baud_rate = -1;
161 
162 /* Timeout limit for response from target.  */
163 
164 /* The default value has been changed many times over the years.  It
165    was originally 5 seconds.  But that was thought to be a long time
166    to sit and wait, so it was changed to 2 seconds.  That was thought
167    to be plenty unless the connection was going through some terminal
168    server or multiplexer or other form of hairy serial connection.
169 
170    In mid-1996, remote_timeout was moved from remote.c to top.c and
171    it began being used in other remote-* targets.  It appears that the
172    default was changed to 20 seconds at that time, perhaps because the
173    Renesas E7000 ICE didn't always respond in a timely manner.
174 
175    But if 5 seconds is a long time to sit and wait for retransmissions,
176    20 seconds is far worse.  This demonstrates the difficulty of using
177    a single variable for all protocol timeouts.
178 
179    As remote.c is used much more than remote-e7000.c, it was changed
180    back to 2 seconds in 1999.  */
181 
182 int remote_timeout = 2;
183 
184 /* Non-zero tells remote* modules to output debugging info.  */
185 
186 int remote_debug = 0;
187 
188 /* Sbrk location on entry to main.  Used for statistics only.  */
189 #ifdef HAVE_SBRK
190 char *lim_at_start;
191 #endif
192 
193 /* Hooks for alternate command interfaces.  */
194 
195 /* Called after most modules have been initialized, but before taking
196    users command file.
197 
198    If the UI fails to initialize and it wants GDB to continue using
199    the default UI, then it should clear this hook before returning.  */
200 
201 void (*deprecated_init_ui_hook) (char *argv0);
202 
203 /* This hook is called from within gdb's many mini-event loops which
204    could steal control from a real user interface's event loop.  It
205    returns non-zero if the user is requesting a detach, zero
206    otherwise.  */
207 
208 int (*deprecated_ui_loop_hook) (int);
209 
210 /* Called instead of command_loop at top level.  Can be invoked via
211    throw_exception().  */
212 
213 void (*deprecated_command_loop_hook) (void);
214 
215 
216 /* Called from print_frame_info to list the line we stopped in.  */
217 
218 void (*deprecated_print_frame_info_listing_hook) (struct symtab * s,
219 						  int line,
220 						  int stopline,
221 						  int noerror);
222 /* Replaces most of query.  */
223 
224 int (*deprecated_query_hook) (const char *, va_list);
225 
226 /* Replaces most of warning.  */
227 
228 void (*deprecated_warning_hook) (const char *, va_list);
229 
230 /* These three functions support getting lines of text from the user.
231    They are used in sequence.  First deprecated_readline_begin_hook is
232    called with a text string that might be (for example) a message for
233    the user to type in a sequence of commands to be executed at a
234    breakpoint.  If this function calls back to a GUI, it might take
235    this opportunity to pop up a text interaction window with this
236    message.  Next, deprecated_readline_hook is called with a prompt
237    that is emitted prior to collecting the user input.  It can be
238    called multiple times.  Finally, deprecated_readline_end_hook is
239    called to notify the GUI that we are done with the interaction
240    window and it can close it.  */
241 
242 void (*deprecated_readline_begin_hook) (char *, ...);
243 char *(*deprecated_readline_hook) (char *);
244 void (*deprecated_readline_end_hook) (void);
245 
246 /* Called as appropriate to notify the interface that we have attached
247    to or detached from an already running process.  */
248 
249 void (*deprecated_attach_hook) (void);
250 void (*deprecated_detach_hook) (void);
251 
252 /* Called during long calculations to allow GUI to repair window
253    damage, and to check for stop buttons, etc...  */
254 
255 void (*deprecated_interactive_hook) (void);
256 
257 /* Tell the GUI someone changed the register REGNO.  -1 means
258    that the caller does not know which register changed or
259    that several registers have changed (see value_assign).  */
260 void (*deprecated_register_changed_hook) (int regno);
261 
262 /* Called when going to wait for the target.  Usually allows the GUI
263    to run while waiting for target events.  */
264 
265 ptid_t (*deprecated_target_wait_hook) (ptid_t ptid,
266 				       struct target_waitstatus *status,
267 				       int options);
268 
269 /* Used by UI as a wrapper around command execution.  May do various
270    things like enabling/disabling buttons, etc...  */
271 
272 void (*deprecated_call_command_hook) (struct cmd_list_element * c,
273 				      char *cmd, int from_tty);
274 
275 /* Called after a `set' command has finished.  Is only run if the
276    `set' command succeeded.  */
277 
278 void (*deprecated_set_hook) (struct cmd_list_element * c);
279 
280 /* Called when the current thread changes.  Argument is thread id.  */
281 
282 void (*deprecated_context_hook) (int id);
283 
284 /* Handler for SIGHUP.  */
285 
286 #ifdef SIGHUP
287 /* NOTE 1999-04-29: This function will be static again, once we modify
288    gdb to use the event loop as the default command loop and we merge
289    event-top.c into this file, top.c.  */
290 /* static */ void
291 quit_cover (void)
292 {
293   /* Stop asking user for confirmation --- we're exiting.  This
294      prevents asking the user dumb questions.  */
295   confirm = 0;
296   quit_command ((char *) 0, 0);
297 }
298 #endif /* defined SIGHUP */
299 
300 /* Line number we are currently in, in a file which is being sourced.  */
301 /* NOTE 1999-04-29: This variable will be static again, once we modify
302    gdb to use the event loop as the default command loop and we merge
303    event-top.c into this file, top.c.  */
304 /* static */ int source_line_number;
305 
306 /* Name of the file we are sourcing.  */
307 /* NOTE 1999-04-29: This variable will be static again, once we modify
308    gdb to use the event loop as the default command loop and we merge
309    event-top.c into this file, top.c.  */
310 /* static */ const char *source_file_name;
311 
312 /* Clean up on error during a "source" command (or execution of a
313    user-defined command).  */
314 
315 void
316 do_restore_instream_cleanup (void *stream)
317 {
318   /* Restore the previous input stream.  */
319   instream = stream;
320 }
321 
322 /* Read commands from STREAM.  */
323 void
324 read_command_file (FILE *stream)
325 {
326   struct cleanup *cleanups;
327 
328   cleanups = make_cleanup (do_restore_instream_cleanup, instream);
329   instream = stream;
330   command_loop ();
331   do_cleanups (cleanups);
332 }
333 
334 void (*pre_init_ui_hook) (void);
335 
336 #ifdef __MSDOS__
337 static void
338 do_chdir_cleanup (void *old_dir)
339 {
340   chdir (old_dir);
341   xfree (old_dir);
342 }
343 #endif
344 
345 struct cleanup *
346 prepare_execute_command (void)
347 {
348   struct value *mark;
349   struct cleanup *cleanup;
350 
351   mark = value_mark ();
352   cleanup = make_cleanup_value_free_to_mark (mark);
353 
354   /* With multiple threads running while the one we're examining is
355      stopped, the dcache can get stale without us being able to detect
356      it.  For the duration of the command, though, use the dcache to
357      help things like backtrace.  */
358   if (non_stop)
359     target_dcache_invalidate ();
360 
361   return cleanup;
362 }
363 
364 /* Tell the user if the language has changed (except first time) after
365    executing a command.  */
366 
367 void
368 check_frame_language_change (void)
369 {
370   static int warned = 0;
371 
372   /* First make sure that a new frame has been selected, in case the
373      command or the hooks changed the program state.  */
374   deprecated_safe_get_selected_frame ();
375   if (current_language != expected_language)
376     {
377       if (language_mode == language_mode_auto && info_verbose)
378 	{
379 	  language_info (1);	/* Print what changed.  */
380 	}
381       warned = 0;
382     }
383 
384   /* Warn the user if the working language does not match the language
385      of the current frame.  Only warn the user if we are actually
386      running the program, i.e. there is a stack.  */
387   /* FIXME: This should be cacheing the frame and only running when
388      the frame changes.  */
389 
390   if (has_stack_frames ())
391     {
392       enum language flang;
393 
394       flang = get_frame_language ();
395       if (!warned
396 	  && flang != language_unknown
397 	  && flang != current_language->la_language)
398 	{
399 	  printf_filtered ("%s\n", lang_frame_mismatch_warn);
400 	  warned = 1;
401 	}
402     }
403 }
404 
405 /* Execute the line P as a command, in the current user context.
406    Pass FROM_TTY as second argument to the defining function.  */
407 
408 void
409 execute_command (char *p, int from_tty)
410 {
411   struct cleanup *cleanup_if_error, *cleanup;
412   struct cmd_list_element *c;
413   char *line;
414 
415   cleanup_if_error = make_bpstat_clear_actions_cleanup ();
416   cleanup = prepare_execute_command ();
417 
418   /* Force cleanup of any alloca areas if using C alloca instead of
419      a builtin alloca.  */
420   alloca (0);
421 
422   /* This can happen when command_line_input hits end of file.  */
423   if (p == NULL)
424     {
425       do_cleanups (cleanup);
426       return;
427     }
428 
429   target_log_command (p);
430 
431   while (*p == ' ' || *p == '\t')
432     p++;
433   if (*p)
434     {
435       char *arg;
436       line = p;
437 
438       /* If trace-commands is set then this will print this command.  */
439       print_command_trace (p);
440 
441       c = lookup_cmd (&p, cmdlist, "", 0, 1);
442 
443       /* Pass null arg rather than an empty one.  */
444       arg = *p ? p : 0;
445 
446       /* FIXME: cagney/2002-02-02: The c->type test is pretty dodgy
447          while the is_complete_command(cfunc) test is just plain
448          bogus.  They should both be replaced by a test of the form
449          c->strip_trailing_white_space_p.  */
450       /* NOTE: cagney/2002-02-02: The function.cfunc in the below
451          can't be replaced with func.  This is because it is the
452          cfunc, and not the func, that has the value that the
453          is_complete_command hack is testing for.  */
454       /* Clear off trailing whitespace, except for set and complete
455          command.  */
456       if (arg
457 	  && c->type != set_cmd
458 	  && !is_complete_command (c))
459 	{
460 	  p = arg + strlen (arg) - 1;
461 	  while (p >= arg && (*p == ' ' || *p == '\t'))
462 	    p--;
463 	  *(p + 1) = '\0';
464 	}
465 
466       /* If this command has been pre-hooked, run the hook first.  */
467       execute_cmd_pre_hook (c);
468 
469       if (c->flags & DEPRECATED_WARN_USER)
470 	deprecated_cmd_warning (&line);
471 
472       /* c->user_commands would be NULL in the case of a python command.  */
473       if (c->class == class_user && c->user_commands)
474 	execute_user_command (c, arg);
475       else if (c->type == set_cmd)
476 	do_set_command (arg, from_tty, c);
477       else if (c->type == show_cmd)
478 	do_show_command (arg, from_tty, c);
479       else if (!cmd_func_p (c))
480 	error (_("That is not a command, just a help topic."));
481       else if (deprecated_call_command_hook)
482 	deprecated_call_command_hook (c, arg, from_tty);
483       else
484 	cmd_func (c, arg, from_tty);
485 
486       /* If the interpreter is in sync mode (we're running a user
487 	 command's list, running command hooks or similars), and we
488 	 just ran a synchronous command that started the target, wait
489 	 for that command to end.  */
490       if (!interpreter_async && sync_execution)
491 	{
492 	  while (gdb_do_one_event () >= 0)
493 	    if (!sync_execution)
494 	      break;
495 	}
496 
497       /* If this command has been post-hooked, run the hook last.  */
498       execute_cmd_post_hook (c);
499 
500     }
501 
502   check_frame_language_change ();
503 
504   do_cleanups (cleanup);
505   discard_cleanups (cleanup_if_error);
506 }
507 
508 /* Run execute_command for P and FROM_TTY.  Capture its output into the
509    returned string, do not display it to the screen.  BATCH_FLAG will be
510    temporarily set to true.  */
511 
512 char *
513 execute_command_to_string (char *p, int from_tty)
514 {
515   struct ui_file *str_file;
516   struct cleanup *cleanup;
517   char *retval;
518 
519   /* GDB_STDOUT should be better already restored during these
520      restoration callbacks.  */
521   cleanup = set_batch_flag_and_make_cleanup_restore_page_info ();
522 
523   make_cleanup_restore_integer (&interpreter_async);
524   interpreter_async = 0;
525 
526   str_file = mem_fileopen ();
527 
528   make_cleanup_ui_file_delete (str_file);
529   make_cleanup_restore_ui_file (&gdb_stdout);
530   make_cleanup_restore_ui_file (&gdb_stderr);
531   make_cleanup_restore_ui_file (&gdb_stdlog);
532   make_cleanup_restore_ui_file (&gdb_stdtarg);
533   make_cleanup_restore_ui_file (&gdb_stdtargerr);
534 
535   if (ui_out_redirect (current_uiout, str_file) < 0)
536     warning (_("Current output protocol does not support redirection"));
537   else
538     make_cleanup_ui_out_redirect_pop (current_uiout);
539 
540   gdb_stdout = str_file;
541   gdb_stderr = str_file;
542   gdb_stdlog = str_file;
543   gdb_stdtarg = str_file;
544   gdb_stdtargerr = str_file;
545 
546   execute_command (p, from_tty);
547 
548   retval = ui_file_xstrdup (str_file, NULL);
549 
550   do_cleanups (cleanup);
551 
552   return retval;
553 }
554 
555 /* Read commands from `instream' and execute them
556    until end of file or error reading instream.  */
557 
558 void
559 command_loop (void)
560 {
561   struct cleanup *old_chain;
562   char *command;
563   int stdin_is_tty = ISATTY (stdin);
564 
565   while (instream && !feof (instream))
566     {
567       if (window_hook && instream == stdin)
568 	(*window_hook) (instream, get_prompt ());
569 
570       clear_quit_flag ();
571       if (instream == stdin && stdin_is_tty)
572 	reinitialize_more_filter ();
573       old_chain = make_cleanup (null_cleanup, 0);
574 
575       /* Get a command-line.  This calls the readline package.  */
576       command = command_line_input (instream == stdin ?
577 				    get_prompt () : (char *) NULL,
578 				    instream == stdin, "prompt");
579       if (command == 0)
580 	{
581 	  do_cleanups (old_chain);
582 	  return;
583 	}
584 
585       make_command_stats_cleanup (1);
586 
587       execute_command (command, instream == stdin);
588 
589       /* Do any commands attached to breakpoint we are stopped at.  */
590       bpstat_do_actions ();
591 
592       do_cleanups (old_chain);
593     }
594 }
595 
596 /* When nonzero, cause dont_repeat to do nothing.  This should only be
597    set via prevent_dont_repeat.  */
598 
599 static int suppress_dont_repeat = 0;
600 
601 /* Commands call this if they do not want to be repeated by null lines.  */
602 
603 void
604 dont_repeat (void)
605 {
606   if (suppress_dont_repeat || server_command)
607     return;
608 
609   /* If we aren't reading from standard input, we are saving the last
610      thing read from stdin in line and don't want to delete it.  Null
611      lines won't repeat here in any case.  */
612   if (instream == stdin)
613     *saved_command_line = 0;
614 }
615 
616 /* Prevent dont_repeat from working, and return a cleanup that
617    restores the previous state.  */
618 
619 struct cleanup *
620 prevent_dont_repeat (void)
621 {
622   struct cleanup *result = make_cleanup_restore_integer (&suppress_dont_repeat);
623 
624   suppress_dont_repeat = 1;
625   return result;
626 }
627 
628 
629 /* Read a line from the stream "instream" without command line editing.
630 
631    It prints PROMPT_ARG once at the start.
632    Action is compatible with "readline", e.g. space for the result is
633    malloc'd and should be freed by the caller.
634 
635    A NULL return means end of file.  */
636 char *
637 gdb_readline (char *prompt_arg)
638 {
639   int c;
640   char *result;
641   int input_index = 0;
642   int result_size = 80;
643 
644   if (prompt_arg)
645     {
646       /* Don't use a _filtered function here.  It causes the assumed
647          character position to be off, since the newline we read from
648          the user is not accounted for.  */
649       fputs_unfiltered (prompt_arg, gdb_stdout);
650       gdb_flush (gdb_stdout);
651     }
652 
653   result = (char *) xmalloc (result_size);
654 
655   while (1)
656     {
657       /* Read from stdin if we are executing a user defined command.
658          This is the right thing for prompt_for_continue, at least.  */
659       c = fgetc (instream ? instream : stdin);
660 
661       if (c == EOF)
662 	{
663 	  if (input_index > 0)
664 	    /* The last line does not end with a newline.  Return it, and
665 	       if we are called again fgetc will still return EOF and
666 	       we'll return NULL then.  */
667 	    break;
668 	  xfree (result);
669 	  return NULL;
670 	}
671 
672       if (c == '\n')
673 	{
674 	  if (input_index > 0 && result[input_index - 1] == '\r')
675 	    input_index--;
676 	  break;
677 	}
678 
679       result[input_index++] = c;
680       while (input_index >= result_size)
681 	{
682 	  result_size *= 2;
683 	  result = (char *) xrealloc (result, result_size);
684 	}
685     }
686 
687   result[input_index++] = '\0';
688   return result;
689 }
690 
691 /* Variables which control command line editing and history
692    substitution.  These variables are given default values at the end
693    of this file.  */
694 static int command_editing_p;
695 
696 /* NOTE 1999-04-29: This variable will be static again, once we modify
697    gdb to use the event loop as the default command loop and we merge
698    event-top.c into this file, top.c.  */
699 
700 /* static */ int history_expansion_p;
701 
702 static int write_history_p;
703 static void
704 show_write_history_p (struct ui_file *file, int from_tty,
705 		      struct cmd_list_element *c, const char *value)
706 {
707   fprintf_filtered (file, _("Saving of the history record on exit is %s.\n"),
708 		    value);
709 }
710 
711 /* The variable associated with the "set/show history size"
712    command.  */
713 static unsigned int history_size_setshow_var;
714 
715 static void
716 show_history_size (struct ui_file *file, int from_tty,
717 		   struct cmd_list_element *c, const char *value)
718 {
719   fprintf_filtered (file, _("The size of the command history is %s.\n"),
720 		    value);
721 }
722 
723 static char *history_filename;
724 static void
725 show_history_filename (struct ui_file *file, int from_tty,
726 		       struct cmd_list_element *c, const char *value)
727 {
728   fprintf_filtered (file, _("The filename in which to record "
729 			    "the command history is \"%s\".\n"),
730 		    value);
731 }
732 
733 /* This is like readline(), but it has some gdb-specific behavior.
734    gdb may want readline in both the synchronous and async modes during
735    a single gdb invocation.  At the ordinary top-level prompt we might
736    be using the async readline.  That means we can't use
737    rl_pre_input_hook, since it doesn't work properly in async mode.
738    However, for a secondary prompt (" >", such as occurs during a
739    `define'), gdb wants a synchronous response.
740 
741    We used to call readline() directly, running it in synchronous
742    mode.  But mixing modes this way is not supported, and as of
743    readline 5.x it no longer works; the arrow keys come unbound during
744    the synchronous call.  So we make a nested call into the event
745    loop.  That's what gdb_readline_wrapper is for.  */
746 
747 /* A flag set as soon as gdb_readline_wrapper_line is called; we can't
748    rely on gdb_readline_wrapper_result, which might still be NULL if
749    the user types Control-D for EOF.  */
750 static int gdb_readline_wrapper_done;
751 
752 /* The result of the current call to gdb_readline_wrapper, once a newline
753    is seen.  */
754 static char *gdb_readline_wrapper_result;
755 
756 /* Any intercepted hook.  Operate-and-get-next sets this, expecting it
757    to be called after the newline is processed (which will redisplay
758    the prompt).  But in gdb_readline_wrapper we will not get a new
759    prompt until the next call, or until we return to the event loop.
760    So we disable this hook around the newline and restore it before we
761    return.  */
762 static void (*saved_after_char_processing_hook) (void);
763 
764 /* This function is called when readline has seen a complete line of
765    text.  */
766 
767 static void
768 gdb_readline_wrapper_line (char *line)
769 {
770   gdb_assert (!gdb_readline_wrapper_done);
771   gdb_readline_wrapper_result = line;
772   gdb_readline_wrapper_done = 1;
773 
774   /* Prevent operate-and-get-next from acting too early.  */
775   saved_after_char_processing_hook = after_char_processing_hook;
776   after_char_processing_hook = NULL;
777 
778   /* Prevent parts of the prompt from being redisplayed if annotations
779      are enabled, and readline's state getting out of sync.  */
780   if (async_command_editing_p)
781     rl_callback_handler_remove ();
782 }
783 
784 struct gdb_readline_wrapper_cleanup
785   {
786     void (*handler_orig) (char *);
787     int already_prompted_orig;
788   };
789 
790 static void
791 gdb_readline_wrapper_cleanup (void *arg)
792 {
793   struct gdb_readline_wrapper_cleanup *cleanup = arg;
794 
795   rl_already_prompted = cleanup->already_prompted_orig;
796 
797   gdb_assert (input_handler == gdb_readline_wrapper_line);
798   input_handler = cleanup->handler_orig;
799   gdb_readline_wrapper_result = NULL;
800   gdb_readline_wrapper_done = 0;
801 
802   after_char_processing_hook = saved_after_char_processing_hook;
803   saved_after_char_processing_hook = NULL;
804 
805   xfree (cleanup);
806 }
807 
808 char *
809 gdb_readline_wrapper (char *prompt)
810 {
811   struct cleanup *back_to;
812   struct gdb_readline_wrapper_cleanup *cleanup;
813   char *retval;
814 
815   cleanup = xmalloc (sizeof (*cleanup));
816   cleanup->handler_orig = input_handler;
817   input_handler = gdb_readline_wrapper_line;
818 
819   cleanup->already_prompted_orig = rl_already_prompted;
820 
821   back_to = make_cleanup (gdb_readline_wrapper_cleanup, cleanup);
822 
823   /* Display our prompt and prevent double prompt display.  */
824   display_gdb_prompt (prompt);
825   rl_already_prompted = 1;
826 
827   if (after_char_processing_hook)
828     (*after_char_processing_hook) ();
829   gdb_assert (after_char_processing_hook == NULL);
830 
831   while (gdb_do_one_event () >= 0)
832     if (gdb_readline_wrapper_done)
833       break;
834 
835   retval = gdb_readline_wrapper_result;
836   do_cleanups (back_to);
837   return retval;
838 }
839 
840 
841 /* The current saved history number from operate-and-get-next.
842    This is -1 if not valid.  */
843 static int operate_saved_history = -1;
844 
845 /* This is put on the appropriate hook and helps operate-and-get-next
846    do its work.  */
847 static void
848 gdb_rl_operate_and_get_next_completion (void)
849 {
850   int delta = where_history () - operate_saved_history;
851 
852   /* The `key' argument to rl_get_previous_history is ignored.  */
853   rl_get_previous_history (delta, 0);
854   operate_saved_history = -1;
855 
856   /* readline doesn't automatically update the display for us.  */
857   rl_redisplay ();
858 
859   after_char_processing_hook = NULL;
860   rl_pre_input_hook = NULL;
861 }
862 
863 /* This is a gdb-local readline command handler.  It accepts the
864    current command line (like RET does) and, if this command was taken
865    from the history, arranges for the next command in the history to
866    appear on the command line when the prompt returns.
867    We ignore the arguments.  */
868 static int
869 gdb_rl_operate_and_get_next (int count, int key)
870 {
871   int where;
872 
873   /* Use the async hook.  */
874   after_char_processing_hook = gdb_rl_operate_and_get_next_completion;
875 
876   /* Find the current line, and find the next line to use.  */
877   where = where_history();
878 
879   /* FIXME: kettenis/20020817: max_input_history is renamed into
880      history_max_entries in readline-4.2.  When we do a new readline
881      import, we should probably change it here too, even though
882      readline maintains backwards compatibility for now by still
883      defining max_input_history.  */
884   if ((history_is_stifled () && (history_length >= max_input_history)) ||
885       (where >= history_length - 1))
886     operate_saved_history = where;
887   else
888     operate_saved_history = where + 1;
889 
890   return rl_newline (1, key);
891 }
892 
893 /* Read one line from the command input stream `instream'
894    into the local static buffer `linebuffer' (whose current length
895    is `linelength').
896    The buffer is made bigger as necessary.
897    Returns the address of the start of the line.
898 
899    NULL is returned for end of file.
900 
901    *If* the instream == stdin & stdin is a terminal, the line read
902    is copied into the file line saver (global var char *line,
903    length linesize) so that it can be duplicated.
904 
905    This routine either uses fancy command line editing or
906    simple input as the user has requested.  */
907 
908 char *
909 command_line_input (char *prompt_arg, int repeat, char *annotation_suffix)
910 {
911   static char *linebuffer = 0;
912   static unsigned linelength = 0;
913   char *p;
914   char *p1;
915   char *rl;
916   char *local_prompt = prompt_arg;
917   char *nline;
918   char got_eof = 0;
919 
920   /* The annotation suffix must be non-NULL.  */
921   if (annotation_suffix == NULL)
922     annotation_suffix = "";
923 
924   if (annotation_level > 1 && instream == stdin)
925     {
926       local_prompt = alloca ((prompt_arg == NULL ? 0 : strlen (prompt_arg))
927 			     + strlen (annotation_suffix) + 40);
928       if (prompt_arg == NULL)
929 	local_prompt[0] = '\0';
930       else
931 	strcpy (local_prompt, prompt_arg);
932       strcat (local_prompt, "\n\032\032");
933       strcat (local_prompt, annotation_suffix);
934       strcat (local_prompt, "\n");
935     }
936 
937   if (linebuffer == 0)
938     {
939       linelength = 80;
940       linebuffer = (char *) xmalloc (linelength);
941     }
942 
943   p = linebuffer;
944 
945   /* Control-C quits instantly if typed while in this loop
946      since it should not wait until the user types a newline.  */
947   immediate_quit++;
948   QUIT;
949 #ifdef STOP_SIGNAL
950   if (job_control)
951     signal (STOP_SIGNAL, handle_stop_sig);
952 #endif
953 
954   while (1)
955     {
956       /* Make sure that all output has been output.  Some machines may
957          let you get away with leaving out some of the gdb_flush, but
958          not all.  */
959       wrap_here ("");
960       gdb_flush (gdb_stdout);
961       gdb_flush (gdb_stderr);
962 
963       if (source_file_name != NULL)
964 	++source_line_number;
965 
966       if (annotation_level > 1 && instream == stdin)
967 	{
968 	  puts_unfiltered ("\n\032\032pre-");
969 	  puts_unfiltered (annotation_suffix);
970 	  puts_unfiltered ("\n");
971 	}
972 
973       /* Don't use fancy stuff if not talking to stdin.  */
974       if (deprecated_readline_hook && input_from_terminal_p ())
975 	{
976 	  rl = (*deprecated_readline_hook) (local_prompt);
977 	}
978       else if (command_editing_p && input_from_terminal_p ())
979 	{
980 	  rl = gdb_readline_wrapper (local_prompt);
981 	}
982       else
983 	{
984 	  rl = gdb_readline (local_prompt);
985 	}
986 
987       if (annotation_level > 1 && instream == stdin)
988 	{
989 	  puts_unfiltered ("\n\032\032post-");
990 	  puts_unfiltered (annotation_suffix);
991 	  puts_unfiltered ("\n");
992 	}
993 
994       if (!rl || rl == (char *) EOF)
995 	{
996 	  got_eof = 1;
997 	  break;
998 	}
999       if (strlen (rl) + 1 + (p - linebuffer) > linelength)
1000 	{
1001 	  linelength = strlen (rl) + 1 + (p - linebuffer);
1002 	  nline = (char *) xrealloc (linebuffer, linelength);
1003 	  p += nline - linebuffer;
1004 	  linebuffer = nline;
1005 	}
1006       p1 = rl;
1007       /* Copy line.  Don't copy null at end.  (Leaves line alone
1008          if this was just a newline).  */
1009       while (*p1)
1010 	*p++ = *p1++;
1011 
1012       xfree (rl);		/* Allocated in readline.  */
1013 
1014       if (p == linebuffer || *(p - 1) != '\\')
1015 	break;
1016 
1017       p--;			/* Put on top of '\'.  */
1018       local_prompt = (char *) 0;
1019     }
1020 
1021 #ifdef STOP_SIGNAL
1022   if (job_control)
1023     signal (STOP_SIGNAL, SIG_DFL);
1024 #endif
1025   immediate_quit--;
1026 
1027   if (got_eof)
1028     return NULL;
1029 
1030 #define SERVER_COMMAND_LENGTH 7
1031   server_command =
1032     (p - linebuffer > SERVER_COMMAND_LENGTH)
1033     && strncmp (linebuffer, "server ", SERVER_COMMAND_LENGTH) == 0;
1034   if (server_command)
1035     {
1036       /* Note that we don't set `line'.  Between this and the check in
1037          dont_repeat, this insures that repeating will still do the
1038          right thing.  */
1039       *p = '\0';
1040       return linebuffer + SERVER_COMMAND_LENGTH;
1041     }
1042 
1043   /* Do history expansion if that is wished.  */
1044   if (history_expansion_p && instream == stdin
1045       && ISATTY (instream))
1046     {
1047       char *history_value;
1048       int expanded;
1049 
1050       *p = '\0';		/* Insert null now.  */
1051       expanded = history_expand (linebuffer, &history_value);
1052       if (expanded)
1053 	{
1054 	  /* Print the changes.  */
1055 	  printf_unfiltered ("%s\n", history_value);
1056 
1057 	  /* If there was an error, call this function again.  */
1058 	  if (expanded < 0)
1059 	    {
1060 	      xfree (history_value);
1061 	      return command_line_input (prompt_arg, repeat,
1062 					 annotation_suffix);
1063 	    }
1064 	  if (strlen (history_value) > linelength)
1065 	    {
1066 	      linelength = strlen (history_value) + 1;
1067 	      linebuffer = (char *) xrealloc (linebuffer, linelength);
1068 	    }
1069 	  strcpy (linebuffer, history_value);
1070 	  p = linebuffer + strlen (linebuffer);
1071 	}
1072       xfree (history_value);
1073     }
1074 
1075   /* If we just got an empty line, and that is supposed to repeat the
1076      previous command, return the value in the global buffer.  */
1077   if (repeat && p == linebuffer)
1078     return saved_command_line;
1079   for (p1 = linebuffer; *p1 == ' ' || *p1 == '\t'; p1++);
1080   if (repeat && !*p1)
1081     return saved_command_line;
1082 
1083   *p = 0;
1084 
1085   /* Add line to history if appropriate.  */
1086   if (instream == stdin
1087       && ISATTY (stdin) && *linebuffer)
1088     add_history (linebuffer);
1089 
1090   /* Note: lines consisting solely of comments are added to the command
1091      history.  This is useful when you type a command, and then
1092      realize you don't want to execute it quite yet.  You can comment
1093      out the command and then later fetch it from the value history
1094      and remove the '#'.  The kill ring is probably better, but some
1095      people are in the habit of commenting things out.  */
1096   if (*p1 == '#')
1097     *p1 = '\0';			/* Found a comment.  */
1098 
1099   /* Save into global buffer if appropriate.  */
1100   if (repeat)
1101     {
1102       if (linelength > saved_command_line_size)
1103 	{
1104 	  saved_command_line = xrealloc (saved_command_line, linelength);
1105 	  saved_command_line_size = linelength;
1106 	}
1107       strcpy (saved_command_line, linebuffer);
1108       return saved_command_line;
1109     }
1110 
1111   return linebuffer;
1112 }
1113 
1114 /* Print the GDB banner.  */
1115 void
1116 print_gdb_version (struct ui_file *stream)
1117 {
1118   /* From GNU coding standards, first line is meant to be easy for a
1119      program to parse, and is just canonical program name and version
1120      number, which starts after last space.  */
1121 
1122   fprintf_filtered (stream, "GNU gdb %s%s\n", PKGVERSION, version);
1123 
1124   /* Second line is a copyright notice.  */
1125 
1126   fprintf_filtered (stream,
1127 		    "Copyright (C) 2013 Free Software Foundation, Inc.\n");
1128 
1129   /* Following the copyright is a brief statement that the program is
1130      free software, that users are free to copy and change it on
1131      certain conditions, that it is covered by the GNU GPL, and that
1132      there is no warranty.  */
1133 
1134   fprintf_filtered (stream, "\
1135 License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>\
1136 \nThis is free software: you are free to change and redistribute it.\n\
1137 There is NO WARRANTY, to the extent permitted by law.  Type \"show copying\"\n\
1138 and \"show warranty\" for details.\n");
1139 
1140   /* After the required info we print the configuration information.  */
1141 
1142   fprintf_filtered (stream, "This GDB was configured as \"");
1143   if (strcmp (host_name, target_name) != 0)
1144     {
1145       fprintf_filtered (stream, "--host=%s --target=%s",
1146 			host_name, target_name);
1147     }
1148   else
1149     {
1150       fprintf_filtered (stream, "%s", host_name);
1151     }
1152   fprintf_filtered (stream, "\".");
1153 
1154   if (REPORT_BUGS_TO[0])
1155     {
1156       fprintf_filtered (stream,
1157 			_("\nFor bug reporting instructions, please see:\n"));
1158       fprintf_filtered (stream, "%s.", REPORT_BUGS_TO);
1159     }
1160 }
1161 
1162 
1163 /* The current top level prompt, settable with "set prompt", and/or
1164    with the python `gdb.prompt_hook' hook.  */
1165 static char *top_prompt;
1166 
1167 /* Access method for the GDB prompt string.  */
1168 
1169 char *
1170 get_prompt (void)
1171 {
1172   return top_prompt;
1173 }
1174 
1175 /* Set method for the GDB prompt string.  */
1176 
1177 void
1178 set_prompt (const char *s)
1179 {
1180   char *p = xstrdup (s);
1181 
1182   xfree (top_prompt);
1183   top_prompt = p;
1184 }
1185 
1186 
1187 struct qt_args
1188 {
1189   char *args;
1190   int from_tty;
1191 };
1192 
1193 /* Callback for iterate_over_inferiors.  Kills or detaches the given
1194    inferior, depending on how we originally gained control of it.  */
1195 
1196 static int
1197 kill_or_detach (struct inferior *inf, void *args)
1198 {
1199   struct qt_args *qt = args;
1200   struct thread_info *thread;
1201 
1202   if (inf->pid == 0)
1203     return 0;
1204 
1205   thread = any_thread_of_process (inf->pid);
1206   if (thread != NULL)
1207     {
1208       switch_to_thread (thread->ptid);
1209 
1210       /* Leave core files alone.  */
1211       if (target_has_execution)
1212 	{
1213 	  if (inf->attach_flag)
1214 	    target_detach (qt->args, qt->from_tty);
1215 	  else
1216 	    target_kill ();
1217 	}
1218     }
1219 
1220   return 0;
1221 }
1222 
1223 /* Callback for iterate_over_inferiors.  Prints info about what GDB
1224    will do to each inferior on a "quit".  ARG points to a struct
1225    ui_out where output is to be collected.  */
1226 
1227 static int
1228 print_inferior_quit_action (struct inferior *inf, void *arg)
1229 {
1230   struct ui_file *stb = arg;
1231 
1232   if (inf->pid == 0)
1233     return 0;
1234 
1235   if (inf->attach_flag)
1236     fprintf_filtered (stb,
1237 		      _("\tInferior %d [%s] will be detached.\n"), inf->num,
1238 		      target_pid_to_str (pid_to_ptid (inf->pid)));
1239   else
1240     fprintf_filtered (stb,
1241 		      _("\tInferior %d [%s] will be killed.\n"), inf->num,
1242 		      target_pid_to_str (pid_to_ptid (inf->pid)));
1243 
1244   return 0;
1245 }
1246 
1247 /* If necessary, make the user confirm that we should quit.  Return
1248    non-zero if we should quit, zero if we shouldn't.  */
1249 
1250 int
1251 quit_confirm (void)
1252 {
1253   struct ui_file *stb;
1254   struct cleanup *old_chain;
1255   char *str;
1256   int qr;
1257 
1258   /* Don't even ask if we're only debugging a core file inferior.  */
1259   if (!have_live_inferiors ())
1260     return 1;
1261 
1262   /* Build the query string as a single string.  */
1263   stb = mem_fileopen ();
1264   old_chain = make_cleanup_ui_file_delete (stb);
1265 
1266   /* This is something of a hack.  But there's no reliable way to see
1267      if a GUI is running.  The `use_windows' variable doesn't cut
1268      it.  */
1269   if (deprecated_init_ui_hook)
1270     fprintf_filtered (stb, _("A debugging session is active.\n"
1271 			     "Do you still want to close the debugger?"));
1272   else
1273     {
1274       fprintf_filtered (stb, _("A debugging session is active.\n\n"));
1275       iterate_over_inferiors (print_inferior_quit_action, stb);
1276       fprintf_filtered (stb, _("\nQuit anyway? "));
1277     }
1278 
1279   str = ui_file_xstrdup (stb, NULL);
1280   make_cleanup (xfree, str);
1281 
1282   qr = query ("%s", str);
1283   do_cleanups (old_chain);
1284   return qr;
1285 }
1286 
1287 /* Helper routine for quit_force that requires error handling.  */
1288 
1289 static int
1290 quit_target (void *arg)
1291 {
1292   struct qt_args *qt = (struct qt_args *)arg;
1293 
1294   /* Kill or detach all inferiors.  */
1295   iterate_over_inferiors (kill_or_detach, qt);
1296 
1297   /* Give all pushed targets a chance to do minimal cleanup, and pop
1298      them all out.  */
1299   pop_all_targets (1);
1300 
1301   /* Save the history information if it is appropriate to do so.  */
1302   if (write_history_p && history_filename)
1303     write_history (history_filename);
1304 
1305   do_final_cleanups (all_cleanups ());    /* Do any final cleanups before
1306 					     exiting.  */
1307   return 0;
1308 }
1309 
1310 /* Quit without asking for confirmation.  */
1311 
1312 void
1313 quit_force (char *args, int from_tty)
1314 {
1315   int exit_code = 0;
1316   struct qt_args qt;
1317 
1318   /* An optional expression may be used to cause gdb to terminate with the
1319      value of that expression.  */
1320   if (args)
1321     {
1322       struct value *val = parse_and_eval (args);
1323 
1324       exit_code = (int) value_as_long (val);
1325     }
1326   else if (return_child_result)
1327     exit_code = return_child_result_value;
1328 
1329   qt.args = args;
1330   qt.from_tty = from_tty;
1331 
1332   /* We want to handle any quit errors and exit regardless.  */
1333   catch_errors (quit_target, &qt,
1334 	        "Quitting: ", RETURN_MASK_ALL);
1335 
1336   exit (exit_code);
1337 }
1338 
1339 /* Returns whether GDB is running on a terminal and input is
1340    currently coming from that terminal.  */
1341 
1342 int
1343 input_from_terminal_p (void)
1344 {
1345   if (batch_flag)
1346     return 0;
1347 
1348   if (gdb_has_a_terminal () && instream == stdin)
1349     return 1;
1350 
1351   /* If INSTREAM is unset, and we are not in a user command, we
1352      must be in Insight.  That's like having a terminal, for our
1353      purposes.  */
1354   if (instream == NULL && !in_user_command)
1355     return 1;
1356 
1357   return 0;
1358 }
1359 
1360 static void
1361 dont_repeat_command (char *ignored, int from_tty)
1362 {
1363   /* Can't call dont_repeat here because we're not necessarily reading
1364      from stdin.  */
1365   *saved_command_line = 0;
1366 }
1367 
1368 /* Functions to manipulate command line editing control variables.  */
1369 
1370 /* Number of commands to print in each call to show_commands.  */
1371 #define Hist_print 10
1372 void
1373 show_commands (char *args, int from_tty)
1374 {
1375   /* Index for history commands.  Relative to history_base.  */
1376   int offset;
1377 
1378   /* Number of the history entry which we are planning to display next.
1379      Relative to history_base.  */
1380   static int num = 0;
1381 
1382   /* Print out some of the commands from the command history.  */
1383 
1384   if (args)
1385     {
1386       if (args[0] == '+' && args[1] == '\0')
1387 	/* "info editing +" should print from the stored position.  */
1388 	;
1389       else
1390 	/* "info editing <exp>" should print around command number <exp>.  */
1391 	num = (parse_and_eval_long (args) - history_base) - Hist_print / 2;
1392     }
1393   /* "show commands" means print the last Hist_print commands.  */
1394   else
1395     {
1396       num = history_length - Hist_print;
1397     }
1398 
1399   if (num < 0)
1400     num = 0;
1401 
1402   /* If there are at least Hist_print commands, we want to display the last
1403      Hist_print rather than, say, the last 6.  */
1404   if (history_length - num < Hist_print)
1405     {
1406       num = history_length - Hist_print;
1407       if (num < 0)
1408 	num = 0;
1409     }
1410 
1411   for (offset = num;
1412        offset < num + Hist_print && offset < history_length;
1413        offset++)
1414     {
1415       printf_filtered ("%5d  %s\n", history_base + offset,
1416 		       (history_get (history_base + offset))->line);
1417     }
1418 
1419   /* The next command we want to display is the next one that we haven't
1420      displayed yet.  */
1421   num += Hist_print;
1422 
1423   /* If the user repeats this command with return, it should do what
1424      "show commands +" does.  This is unnecessary if arg is null,
1425      because "show commands +" is not useful after "show commands".  */
1426   if (from_tty && args)
1427     {
1428       args[0] = '+';
1429       args[1] = '\0';
1430     }
1431 }
1432 
1433 /* Called by do_setshow_command.  */
1434 static void
1435 set_history_size_command (char *args, int from_tty, struct cmd_list_element *c)
1436 {
1437   /* Readline's history interface works with 'int', so it can only
1438      handle history sizes up to INT_MAX.  The command itself is
1439      uinteger, so UINT_MAX means "unlimited", but we only get that if
1440      the user does "set history size 0" -- "set history size <UINT_MAX>"
1441      throws out-of-range.  */
1442   if (history_size_setshow_var > INT_MAX
1443       && history_size_setshow_var != UINT_MAX)
1444     {
1445       unsigned int new_value = history_size_setshow_var;
1446 
1447       /* Restore previous value before throwing.  */
1448       if (history_is_stifled ())
1449 	history_size_setshow_var = history_max_entries;
1450       else
1451 	history_size_setshow_var = UINT_MAX;
1452 
1453       error (_("integer %u out of range"), new_value);
1454     }
1455 
1456   /* Commit the new value to readline's history.  */
1457   if (history_size_setshow_var == UINT_MAX)
1458     unstifle_history ();
1459   else
1460     stifle_history (history_size_setshow_var);
1461 }
1462 
1463 void
1464 set_history (char *args, int from_tty)
1465 {
1466   printf_unfiltered (_("\"set history\" must be followed "
1467 		       "by the name of a history subcommand.\n"));
1468   help_list (sethistlist, "set history ", -1, gdb_stdout);
1469 }
1470 
1471 void
1472 show_history (char *args, int from_tty)
1473 {
1474   cmd_show_list (showhistlist, from_tty, "");
1475 }
1476 
1477 int info_verbose = 0;		/* Default verbose msgs off.  */
1478 
1479 /* Called by do_setshow_command.  An elaborate joke.  */
1480 void
1481 set_verbose (char *args, int from_tty, struct cmd_list_element *c)
1482 {
1483   char *cmdname = "verbose";
1484   struct cmd_list_element *showcmd;
1485 
1486   showcmd = lookup_cmd_1 (&cmdname, showlist, NULL, 1);
1487   gdb_assert (showcmd != NULL && showcmd != CMD_LIST_AMBIGUOUS);
1488 
1489   if (info_verbose)
1490     {
1491       c->doc = "Set verbose printing of informational messages.";
1492       showcmd->doc = "Show verbose printing of informational messages.";
1493     }
1494   else
1495     {
1496       c->doc = "Set verbosity.";
1497       showcmd->doc = "Show verbosity.";
1498     }
1499 }
1500 
1501 /* Init the history buffer.  Note that we are called after the init file(s)
1502    have been read so that the user can change the history file via his
1503    .gdbinit file (for instance).  The GDBHISTFILE environment variable
1504    overrides all of this.  */
1505 
1506 void
1507 init_history (void)
1508 {
1509   char *tmpenv;
1510 
1511   tmpenv = getenv ("HISTSIZE");
1512   if (tmpenv)
1513     {
1514       int var;
1515 
1516       var = atoi (tmpenv);
1517       if (var < 0)
1518 	{
1519 	  /* Prefer ending up with no history rather than overflowing
1520 	     readline's history interface, which uses signed 'int'
1521 	     everywhere.  */
1522 	  var = 0;
1523 	}
1524 
1525       history_size_setshow_var = var;
1526     }
1527   /* If the init file hasn't set a size yet, pick the default.  */
1528   else if (history_size_setshow_var == 0)
1529     history_size_setshow_var = 256;
1530 
1531   /* Note that unlike "set history size 0", "HISTSIZE=0" really sets
1532      the history size to 0...  */
1533   stifle_history (history_size_setshow_var);
1534 
1535   tmpenv = getenv ("GDBHISTFILE");
1536   if (tmpenv)
1537     history_filename = xstrdup (tmpenv);
1538   else if (!history_filename)
1539     {
1540       /* We include the current directory so that if the user changes
1541          directories the file written will be the same as the one
1542          that was read.  */
1543 #ifdef __MSDOS__
1544       /* No leading dots in file names are allowed on MSDOS.  */
1545       history_filename = concat (current_directory, "/_gdb_history",
1546 				 (char *)NULL);
1547 #else
1548       history_filename = concat (current_directory, "/.gdb_history",
1549 				 (char *)NULL);
1550 #endif
1551     }
1552   read_history (history_filename);
1553 }
1554 
1555 static void
1556 show_prompt (struct ui_file *file, int from_tty,
1557 	     struct cmd_list_element *c, const char *value)
1558 {
1559   fprintf_filtered (file, _("Gdb's prompt is \"%s\".\n"), value);
1560 }
1561 
1562 static void
1563 show_async_command_editing_p (struct ui_file *file, int from_tty,
1564 			      struct cmd_list_element *c, const char *value)
1565 {
1566   fprintf_filtered (file, _("Editing of command lines as "
1567 			    "they are typed is %s.\n"),
1568 		    value);
1569 }
1570 
1571 static void
1572 show_annotation_level (struct ui_file *file, int from_tty,
1573 		       struct cmd_list_element *c, const char *value)
1574 {
1575   fprintf_filtered (file, _("Annotation_level is %s.\n"), value);
1576 }
1577 
1578 static void
1579 show_exec_done_display_p (struct ui_file *file, int from_tty,
1580 			  struct cmd_list_element *c, const char *value)
1581 {
1582   fprintf_filtered (file, _("Notification of completion for "
1583 			    "asynchronous execution commands is %s.\n"),
1584 		    value);
1585 }
1586 
1587 /* "set" command for the gdb_datadir configuration variable.  */
1588 
1589 static void
1590 set_gdb_datadir (char *args, int from_tty, struct cmd_list_element *c)
1591 {
1592   observer_notify_gdb_datadir_changed ();
1593 }
1594 
1595 static void
1596 init_main (void)
1597 {
1598   /* Initialize the prompt to a simple "(gdb) " prompt or to whatever
1599      the DEFAULT_PROMPT is.  */
1600   set_prompt (DEFAULT_PROMPT);
1601 
1602   /* Set things up for annotation_level > 1, if the user ever decides
1603      to use it.  */
1604   async_annotation_suffix = "prompt";
1605 
1606   /* Set the important stuff up for command editing.  */
1607   command_editing_p = 1;
1608   history_expansion_p = 0;
1609   write_history_p = 0;
1610 
1611   /* Setup important stuff for command line editing.  */
1612   rl_completion_word_break_hook = gdb_completion_word_break_characters;
1613   rl_completion_entry_function = readline_line_completion_function;
1614   rl_completer_word_break_characters = default_word_break_characters ();
1615   rl_completer_quote_characters = get_gdb_completer_quote_characters ();
1616   rl_readline_name = "gdb";
1617   rl_terminal_name = getenv ("TERM");
1618 
1619   /* The name for this defun comes from Bash, where it originated.
1620      15 is Control-o, the same binding this function has in Bash.  */
1621   rl_add_defun ("operate-and-get-next", gdb_rl_operate_and_get_next, 15);
1622 
1623   add_setshow_string_cmd ("prompt", class_support,
1624 			  &top_prompt,
1625 			  _("Set gdb's prompt"),
1626 			  _("Show gdb's prompt"),
1627 			  NULL, NULL,
1628 			  show_prompt,
1629 			  &setlist, &showlist);
1630 
1631   add_com ("dont-repeat", class_support, dont_repeat_command, _("\
1632 Don't repeat this command.\nPrimarily \
1633 used inside of user-defined commands that should not be repeated when\n\
1634 hitting return."));
1635 
1636   add_setshow_boolean_cmd ("editing", class_support,
1637 			   &async_command_editing_p, _("\
1638 Set editing of command lines as they are typed."), _("\
1639 Show editing of command lines as they are typed."), _("\
1640 Use \"on\" to enable the editing, and \"off\" to disable it.\n\
1641 Without an argument, command line editing is enabled.  To edit, use\n\
1642 EMACS-like or VI-like commands like control-P or ESC."),
1643 			   set_async_editing_command,
1644 			   show_async_command_editing_p,
1645 			   &setlist, &showlist);
1646 
1647   add_setshow_boolean_cmd ("save", no_class, &write_history_p, _("\
1648 Set saving of the history record on exit."), _("\
1649 Show saving of the history record on exit."), _("\
1650 Use \"on\" to enable the saving, and \"off\" to disable it.\n\
1651 Without an argument, saving is enabled."),
1652 			   NULL,
1653 			   show_write_history_p,
1654 			   &sethistlist, &showhistlist);
1655 
1656   add_setshow_uinteger_cmd ("size", no_class, &history_size_setshow_var, _("\
1657 Set the size of the command history,"), _("\
1658 Show the size of the command history,"), _("\
1659 ie. the number of previous commands to keep a record of."),
1660 			    set_history_size_command,
1661 			    show_history_size,
1662 			    &sethistlist, &showhistlist);
1663 
1664   add_setshow_filename_cmd ("filename", no_class, &history_filename, _("\
1665 Set the filename in which to record the command history"), _("\
1666 Show the filename in which to record the command history"), _("\
1667 (the list of previous commands of which a record is kept)."),
1668 			    NULL,
1669 			    show_history_filename,
1670 			    &sethistlist, &showhistlist);
1671 
1672   add_setshow_boolean_cmd ("confirm", class_support, &confirm, _("\
1673 Set whether to confirm potentially dangerous operations."), _("\
1674 Show whether to confirm potentially dangerous operations."), NULL,
1675 			   NULL,
1676 			   show_confirm,
1677 			   &setlist, &showlist);
1678 
1679   add_setshow_zinteger_cmd ("annotate", class_obscure, &annotation_level, _("\
1680 Set annotation_level."), _("\
1681 Show annotation_level."), _("\
1682 0 == normal;     1 == fullname (for use when running under emacs)\n\
1683 2 == output annotated suitably for use by programs that control GDB."),
1684 			    NULL,
1685 			    show_annotation_level,
1686 			    &setlist, &showlist);
1687 
1688   add_setshow_boolean_cmd ("exec-done-display", class_support,
1689 			   &exec_done_display_p, _("\
1690 Set notification of completion for asynchronous execution commands."), _("\
1691 Show notification of completion for asynchronous execution commands."), _("\
1692 Use \"on\" to enable the notification, and \"off\" to disable it."),
1693 			   NULL,
1694 			   show_exec_done_display_p,
1695 			   &setlist, &showlist);
1696 
1697   add_setshow_filename_cmd ("data-directory", class_maintenance,
1698                            &gdb_datadir, _("Set GDB's data directory."),
1699                            _("Show GDB's data directory."),
1700                            _("\
1701 When set, GDB uses the specified path to search for data files."),
1702                            set_gdb_datadir, NULL,
1703                            &setlist,
1704                            &showlist);
1705 }
1706 
1707 void
1708 gdb_init (char *argv0)
1709 {
1710   if (pre_init_ui_hook)
1711     pre_init_ui_hook ();
1712 
1713   /* Run the init function of each source file.  */
1714 
1715 #ifdef __MSDOS__
1716   /* Make sure we return to the original directory upon exit, come
1717      what may, since the OS doesn't do that for us.  */
1718   make_final_cleanup (do_chdir_cleanup, xstrdup (current_directory));
1719 #endif
1720 
1721   init_cmd_lists ();	    /* This needs to be done first.  */
1722   initialize_targets ();    /* Setup target_terminal macros for utils.c.  */
1723   initialize_utils ();	    /* Make errors and warnings possible.  */
1724 
1725   /* Here is where we call all the _initialize_foo routines.  */
1726   initialize_all_files ();
1727 
1728   /* This creates the current_program_space.  Do this after all the
1729      _initialize_foo routines have had a chance to install their
1730      per-sspace data keys.  Also do this before
1731      initialize_current_architecture is called, because it accesses
1732      exec_bfd of the current program space.  */
1733   initialize_progspace ();
1734   initialize_inferiors ();
1735   initialize_current_architecture ();
1736   init_cli_cmds();
1737   initialize_event_loop ();
1738   init_main ();			/* But that omits this file!  Do it now.  */
1739 
1740   initialize_stdin_serial ();
1741 
1742   async_init_signals ();
1743 
1744   /* We need a default language for parsing expressions, so simple
1745      things like "set width 0" won't fail if no language is explicitly
1746      set in a config file or implicitly set by reading an executable
1747      during startup.  */
1748   set_language (language_c);
1749   expected_language = current_language;	/* Don't warn about the change.  */
1750 
1751   /* Allow another UI to initialize.  If the UI fails to initialize,
1752      and it wants GDB to revert to the CLI, it should clear
1753      deprecated_init_ui_hook.  */
1754   if (deprecated_init_ui_hook)
1755     deprecated_init_ui_hook (argv0);
1756 
1757 #ifdef HAVE_PYTHON
1758   /* Python initialization can require various commands to be
1759      installed.  For example "info pretty-printer" needs the "info"
1760      prefix to be installed.  Keep things simple and just do final
1761      python initialization here.  */
1762   finish_python_initialization ();
1763 #endif
1764 }
1765