1 /* Top level stuff for GDB, the GNU debugger.
2 Copyright 1999 Free Software Foundation, Inc.
3 Written by Elena Zannoni <ezannoni@cygnus.com> of Cygnus Solutions.
5 This file is part of GDB.
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 2 of the License, or
10 (at your option) any later version.
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.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
25 #include "terminal.h" /* for job_control */
27 #include "event-loop.h"
28 #include "event-top.h"
30 /* For dont_repeat() */
33 /* readline include files */
34 #include <readline/readline.h>
35 #include <readline/history.h>
37 /* readline defines this. */
40 extern void _initialize_event_loop (void);
42 static void rl_callback_read_char_wrapper (gdb_client_data client_data
);
43 static void command_line_handler (char *rl
);
44 static void command_line_handler_continuation (struct continuation_arg
*arg
);
45 static void change_line_handler (void);
46 static void change_annotation_level (void);
47 static void command_handler (char *command
);
48 void cli_command_loop (void);
49 static void async_do_nothing (gdb_client_data arg
);
50 static void async_disconnect (gdb_client_data arg
);
51 static void async_stop_sig (gdb_client_data arg
);
52 static void async_float_handler (gdb_client_data arg
);
54 /* Signal handlers. */
55 static void handle_sigquit (int sig
);
56 static void handle_sighup (int sig
);
57 static void handle_sigfpe (int sig
);
58 #if defined(SIGWINCH) && defined(SIGWINCH_HANDLER)
59 static void handle_sigwinch (int sig
);
62 /* Functions to be invoked by the event loop in response to
64 static void async_do_nothing (gdb_client_data
);
65 static void async_disconnect (gdb_client_data
);
66 static void async_float_handler (gdb_client_data
);
67 static void async_stop_sig (gdb_client_data
);
69 /* Readline offers an alternate interface, via callback
70 functions. These are all included in the file callback.c in the
71 readline distribution. This file provides (mainly) a function, which
72 the event loop uses as callback (i.e. event handler) whenever an event
73 is detected on the standard input file descriptor.
74 readline_callback_read_char is called (by the GDB event loop) whenever
75 there is a new character ready on the input stream. This function
76 incrementally builds a buffer internal to readline where it
77 accumulates the line read up to the point of invocation. In the
78 special case in which the character read is newline, the function
79 invokes a GDB supplied callback routine, which does the processing of
80 a full command line. This latter routine is the asynchronous analog
81 of the old command_line_input in gdb. Instead of invoking (and waiting
82 for) readline to read the command line and pass it back to
83 command_loop for processing, the new command_line_handler function has
84 the command line already available as its parameter. INPUT_HANDLER is
85 to be set to the function that readline will invoke when a complete
86 line of input is ready. CALL_READLINE is to be set to the function
87 that readline offers as callback to the event_loop. */
89 void (*input_handler
) (char *);
90 void (*call_readline
) (gdb_client_data
);
92 /* Important variables for the event loop. */
94 /* This is used to determine if GDB is using the readline library or
95 its own simplified form of readline. It is used by the asynchronous
96 form of the set editing command.
97 ezannoni: as of 1999-04-29 I expect that this
98 variable will not be used after gdb is changed to use the event
99 loop as default engine, and event-top.c is merged into top.c. */
100 int async_command_editing_p
;
102 /* This variable contains the new prompt that the user sets with the
103 set prompt command. */
104 char *new_async_prompt
;
106 /* This is the annotation suffix that will be used when the
107 annotation_level is 2. */
108 char *async_annotation_suffix
;
110 /* This is used to display the notification of the completion of an
111 asynchronous execution command. */
112 int exec_done_display_p
= 0;
114 /* This is the file descriptor for the input stream that GDB uses to
115 read commands from. */
118 /* This is the prompt stack. Prompts will be pushed on the stack as
119 needed by the different 'kinds' of user inputs GDB is asking
120 for. See event-loop.h. */
121 struct prompts the_prompts
;
123 /* signal handling variables */
124 /* Each of these is a pointer to a function that the event loop will
125 invoke if the corresponding signal has received. The real signal
126 handlers mark these functions as ready to be executed and the event
127 loop, in a later iteration, calls them. See the function
128 invoke_async_signal_handler. */
135 #if defined(SIGWINCH) && defined(SIGWINCH_HANDLER)
142 /* Structure to save a partially entered command. This is used when
143 the user types '\' at the end of a command line. This is necessary
144 because each line of input is handled by a different call to
145 command_line_handler, and normally there is no state retained
146 between different calls. */
147 int more_to_come
= 0;
149 struct readline_input_state
152 char *linebuffer_ptr
;
154 readline_input_state
;
157 /* Wrapper function foe calling into the readline library. The event
158 loop expects the callback function to have a paramter, while readline
161 rl_callback_read_char_wrapper (gdb_client_data client_data
)
163 rl_callback_read_char ();
166 /* Initialize all the necessary variables, start the event loop,
167 register readline, and stdin, start the loop. */
169 cli_command_loop (void)
173 char *gdb_prompt
= get_prompt ();
175 /* If we are using readline, set things up and display the first
176 prompt, otherwise just print the prompt. */
177 if (async_command_editing_p
)
179 /* Tell readline what the prompt to display is and what function it
180 will need to call after a whole line is read. This also displays
182 length
= strlen (PREFIX (0)) + strlen (gdb_prompt
) + strlen (SUFFIX (0)) + 1;
183 a_prompt
= (char *) xmalloc (length
);
184 strcpy (a_prompt
, PREFIX (0));
185 strcat (a_prompt
, gdb_prompt
);
186 strcat (a_prompt
, SUFFIX (0));
187 rl_callback_handler_install (a_prompt
, input_handler
);
190 display_gdb_prompt (0);
192 /* Now it's time to start the event loop. */
196 /* Change the function to be invoked every time there is a character
197 ready on stdin. This is used when the user sets the editing off,
198 therefore bypassing readline, and letting gdb handle the input
199 itself, via gdb_readline2. Also it is used in the opposite case in
200 which the user sets editing on again, by restoring readline
201 handling of the input. */
203 change_line_handler (void)
205 /* NOTE: this operates on input_fd, not instream. If we are reading
206 commands from a file, instream will point to the file. However in
207 async mode, we always read commands from a file with editing
208 off. This means that the 'set editing on/off' will have effect
209 only on the interactive session. */
211 if (async_command_editing_p
)
213 /* Turn on editing by using readline. */
214 call_readline
= rl_callback_read_char_wrapper
;
215 input_handler
= command_line_handler
;
219 /* Turn off editing by using gdb_readline2. */
220 rl_callback_handler_remove ();
221 call_readline
= gdb_readline2
;
223 /* Set up the command handler as well, in case we are called as
224 first thing from .gdbinit. */
225 input_handler
= command_line_handler
;
229 /* Displays the prompt. The prompt that is displayed is the current
230 top of the prompt stack, if the argument NEW_PROMPT is
231 0. Otherwise, it displays whatever NEW_PROMPT is. This is used
232 after each gdb command has completed, and in the following cases:
233 1. when the user enters a command line which is ended by '\'
234 indicating that the command will continue on the next line.
235 In that case the prompt that is displayed is the empty string.
236 2. When the user is entering 'commands' for a breakpoint, or
237 actions for a tracepoint. In this case the prompt will be '>'
239 FIXME: 2. & 3. not implemented yet for async. */
241 display_gdb_prompt (char *new_prompt
)
243 int prompt_length
= 0;
244 char *gdb_prompt
= get_prompt ();
247 if (target_executing
&& sync_execution
)
249 /* This is to trick readline into not trying to display the
250 prompt. Even though we display the prompt using this
251 function, readline still tries to do its own display if we
252 don't call rl_callback_handler_install and
253 rl_callback_handler_remove (which readline detects because a
254 global variable is not set). If readline did that, it could
255 mess up gdb signal handlers for SIGINT. Readline assumes
256 that between calls to rl_set_signals and rl_clear_signals gdb
257 doesn't do anything with the signal handlers. Well, that's
258 not the case, because when the target executes we change the
259 SIGINT signal handler. If we allowed readline to display the
260 prompt, the signal handler change would happen exactly
261 between the calls to the above two functions.
262 Calling rl_callback_handler_remove(), does the job. */
264 rl_callback_handler_remove ();
270 /* Just use the top of the prompt stack. */
271 prompt_length
= strlen (PREFIX (0)) +
272 strlen (SUFFIX (0)) +
273 strlen (gdb_prompt
) + 1;
275 new_prompt
= (char *) alloca (prompt_length
);
277 /* Prefix needs to have new line at end. */
278 strcpy (new_prompt
, PREFIX (0));
279 strcat (new_prompt
, gdb_prompt
);
280 /* Suffix needs to have a new line at end and \032 \032 at
282 strcat (new_prompt
, SUFFIX (0));
285 if (async_command_editing_p
)
287 rl_callback_handler_remove ();
288 rl_callback_handler_install (new_prompt
, input_handler
);
290 /* new_prompt at this point can be the top of the stack or the one passed in */
293 /* Don't use a _filtered function here. It causes the assumed
294 character position to be off, since the newline we read from
295 the user is not accounted for. */
296 fputs_unfiltered (new_prompt
, gdb_stdout
);
299 /* Move to a new line so the entered line doesn't have a prompt
300 on the front of it. */
301 fputs_unfiltered ("\n", gdb_stdout
);
303 gdb_flush (gdb_stdout
);
307 /* Used when the user requests a different annotation level, with
308 'set annotate'. It pushes a new prompt (with prefix and suffix) on top
309 of the prompt stack, if the annotation level desired is 2, otherwise
310 it pops the top of the prompt stack when we want the annotation level
311 to be the normal ones (1 or 0). */
313 change_annotation_level (void)
315 char *prefix
, *suffix
;
317 if (!PREFIX (0) || !PROMPT (0) || !SUFFIX (0))
319 /* The prompt stack has not been initialized to "", we are
320 using gdb w/o the --async switch */
321 warning ("Command has same effect as set annotate");
325 if (annotation_level
> 1)
327 if (!strcmp (PREFIX (0), "") && !strcmp (SUFFIX (0), ""))
329 /* Push a new prompt if the previous annotation_level was not >1. */
330 prefix
= (char *) alloca (strlen (async_annotation_suffix
) + 10);
331 strcpy (prefix
, "\n\032\032pre-");
332 strcat (prefix
, async_annotation_suffix
);
333 strcat (prefix
, "\n");
335 suffix
= (char *) alloca (strlen (async_annotation_suffix
) + 6);
336 strcpy (suffix
, "\n\032\032");
337 strcat (suffix
, async_annotation_suffix
);
338 strcat (suffix
, "\n");
340 push_prompt (prefix
, (char *) 0, suffix
);
345 if (strcmp (PREFIX (0), "") && strcmp (SUFFIX (0), ""))
347 /* Pop the top of the stack, we are going back to annotation < 1. */
353 /* Pushes a new prompt on the prompt stack. Each prompt has three
354 parts: prefix, prompt, suffix. Usually prefix and suffix are empty
355 strings, except when the annotation level is 2. Memory is allocated
356 within savestring for the new prompt. */
358 push_prompt (char *prefix
, char *prompt
, char *suffix
)
361 PREFIX (0) = savestring (prefix
, strlen (prefix
));
363 /* Note that this function is used by the set annotate 2
364 command. This is why we take care of saving the old prompt
365 in case a new one is not specified. */
367 PROMPT (0) = savestring (prompt
, strlen (prompt
));
369 PROMPT (0) = savestring (PROMPT (-1), strlen (PROMPT (-1)));
371 SUFFIX (0) = savestring (suffix
, strlen (suffix
));
374 /* Pops the top of the prompt stack, and frees the memory allocated for it. */
378 /* If we are not during a 'synchronous' execution command, in which
379 case, the top prompt would be empty. */
380 if (strcmp (PROMPT (0), ""))
381 /* This is for the case in which the prompt is set while the
382 annotation level is 2. The top prompt will be changed, but when
383 we return to annotation level < 2, we want that new prompt to be
384 in effect, until the user does another 'set prompt'. */
385 if (strcmp (PROMPT (0), PROMPT (-1)))
388 PROMPT (-1) = savestring (PROMPT (0), strlen (PROMPT (0)));
397 /* When there is an event ready on the stdin file desriptor, instead
398 of calling readline directly throught the callback function, or
399 instead of calling gdb_readline2, give gdb a chance to detect
400 errors and do something. */
402 stdin_event_handler (int error
, int fd
, gdb_client_data client_data
)
406 printf_unfiltered ("error detected on stdin, fd %d\n", fd
);
407 delete_file_handler (fd
);
408 discard_all_continuations ();
409 /* If stdin died, we may as well kill gdb. */
413 (*call_readline
) (client_data
);
417 /* Handles a gdb command. This function is called by
418 command_line_handler, which has processed one or more input lines
420 /* NOTE: 1999-04-30 This is the asynchronous version of the command_loop
421 function. The command_loop function will be obsolete when we
422 switch to use the event loop at every execution of gdb. */
424 command_handler (char *command
)
426 struct cleanup
*old_chain
;
427 int stdin_is_tty
= ISATTY (stdin
);
428 struct continuation_arg
*arg1
;
429 struct continuation_arg
*arg2
;
430 long time_at_cmd_start
;
432 long space_at_cmd_start
= 0;
434 extern int display_time
;
435 extern int display_space
;
438 extern int insert_mode
;
442 if (instream
== stdin
&& stdin_is_tty
)
443 reinitialize_more_filter ();
444 old_chain
= make_cleanup ((make_cleanup_func
) command_loop_marker
, 0);
449 /* If readline returned a NULL command, it means that the
450 connection with the terminal is gone. This happens at the
451 end of a testsuite run, after Expect has hung up
452 but GDB is still alive. In such a case, we just quit gdb
453 killing the inferior program too. */
455 quit_command ((char *) 0, stdin
== instream
);
457 time_at_cmd_start
= get_run_time ();
462 extern char **environ
;
463 char *lim
= (char *) sbrk (0);
465 space_at_cmd_start
= (long) (lim
- (char *) &environ
);
469 execute_command (command
, instream
== stdin
);
471 /* Set things up for this function to be compete later, once the
472 executin has completed, if we are doing an execution command,
473 otherwise, just go ahead and finish. */
474 if (target_has_async
&& target_executing
)
477 (struct continuation_arg
*) xmalloc (sizeof (struct continuation_arg
));
479 (struct continuation_arg
*) xmalloc (sizeof (struct continuation_arg
));
482 arg1
->data
= (PTR
) time_at_cmd_start
;
483 arg2
->data
= (PTR
) space_at_cmd_start
;
484 add_continuation (command_line_handler_continuation
, arg1
);
487 /* Do any commands attached to breakpoint we stopped at. Only if we
488 are always running synchronously. Or if we have just executed a
489 command that doesn't start the target. */
490 if (!target_has_async
|| !target_executing
)
492 bpstat_do_actions (&stop_bpstat
);
493 do_cleanups (old_chain
);
497 long cmd_time
= get_run_time () - time_at_cmd_start
;
499 printf_unfiltered ("Command execution time: %ld.%06ld\n",
500 cmd_time
/ 1000000, cmd_time
% 1000000);
506 extern char **environ
;
507 char *lim
= (char *) sbrk (0);
508 long space_now
= lim
- (char *) &environ
;
509 long space_diff
= space_now
- space_at_cmd_start
;
511 printf_unfiltered ("Space used: %ld (%c%ld for this command)\n",
513 (space_diff
>= 0 ? '+' : '-'),
520 /* Do any commands attached to breakpoint we stopped at. Only if we
521 are always running synchronously. Or if we have just executed a
522 command that doesn't start the target. */
524 command_line_handler_continuation (struct continuation_arg
*arg
)
526 extern int display_time
;
527 extern int display_space
;
529 long time_at_cmd_start
= (long) arg
->data
;
530 long space_at_cmd_start
= (long) arg
->next
->data
;
532 bpstat_do_actions (&stop_bpstat
);
533 /*do_cleanups (old_chain); *//*?????FIXME????? */
537 long cmd_time
= get_run_time () - time_at_cmd_start
;
539 printf_unfiltered ("Command execution time: %ld.%06ld\n",
540 cmd_time
/ 1000000, cmd_time
% 1000000);
545 extern char **environ
;
546 char *lim
= (char *) sbrk (0);
547 long space_now
= lim
- (char *) &environ
;
548 long space_diff
= space_now
- space_at_cmd_start
;
550 printf_unfiltered ("Space used: %ld (%c%ld for this command)\n",
552 (space_diff
>= 0 ? '+' : '-'),
558 /* Handle a complete line of input. This is called by the callback
559 mechanism within the readline library. Deal with incomplete commands
560 as well, by saving the partial input in a global buffer. */
562 /* NOTE: 1999-04-30 This is the asynchronous version of the
563 command_line_input function. command_line_input will become
564 obsolete once we use the event loop as the default mechanism in
567 command_line_handler (char *rl
)
569 static char *linebuffer
= 0;
570 static unsigned linelength
= 0;
579 int repeat
= (instream
== stdin
);
581 if (annotation_level
> 1 && instream
== stdin
)
583 printf_unfiltered ("\n\032\032post-");
584 printf_unfiltered (async_annotation_suffix
);
585 printf_unfiltered ("\n");
591 linebuffer
= (char *) xmalloc (linelength
);
598 strcpy (linebuffer
, readline_input_state
.linebuffer
);
599 p
= readline_input_state
.linebuffer_ptr
;
600 free (readline_input_state
.linebuffer
);
607 signal (STOP_SIGNAL
, handle_stop_sig
);
610 /* Make sure that all output has been output. Some machines may let
611 you get away with leaving out some of the gdb_flush, but not all. */
613 gdb_flush (gdb_stdout
);
614 gdb_flush (gdb_stderr
);
616 if (source_file_name
!= NULL
)
618 ++source_line_number
;
619 sprintf (source_error
,
620 "%s%s:%d: Error in sourced command file:\n",
624 error_pre_print
= source_error
;
627 /* If we are in this case, then command_handler will call quit
628 and exit from gdb. */
629 if (!rl
|| rl
== (char *) EOF
)
634 if (strlen (rl
) + 1 + (p
- linebuffer
) > linelength
)
636 linelength
= strlen (rl
) + 1 + (p
- linebuffer
);
637 nline
= (char *) xrealloc (linebuffer
, linelength
);
638 p
+= nline
- linebuffer
;
642 /* Copy line. Don't copy null at end. (Leaves line alone
643 if this was just a newline) */
647 free (rl
); /* Allocated in readline. */
649 if (*(p
- 1) == '\\')
651 p
--; /* Put on top of '\'. */
655 readline_input_state
.linebuffer
= savestring (linebuffer
,
656 strlen (linebuffer
));
657 readline_input_state
.linebuffer_ptr
= p
;
659 /* We will not invoke a execute_command if there is more
660 input expected to complete the command. So, we need to
661 print an empty prompt here. */
663 push_prompt ("", "", "");
664 display_gdb_prompt (0);
671 signal (STOP_SIGNAL
, SIG_DFL
);
674 #define SERVER_COMMAND_LENGTH 7
676 (p
- linebuffer
> SERVER_COMMAND_LENGTH
)
677 && STREQN (linebuffer
, "server ", SERVER_COMMAND_LENGTH
);
680 /* Note that we don't set `line'. Between this and the check in
681 dont_repeat, this insures that repeating will still do the
684 command_handler (linebuffer
+ SERVER_COMMAND_LENGTH
);
685 display_gdb_prompt (0);
689 /* Do history expansion if that is wished. */
690 if (history_expansion_p
&& instream
== stdin
691 && ISATTY (instream
))
696 *p
= '\0'; /* Insert null now. */
697 expanded
= history_expand (linebuffer
, &history_value
);
700 /* Print the changes. */
701 printf_unfiltered ("%s\n", history_value
);
703 /* If there was an error, call this function again. */
706 free (history_value
);
709 if (strlen (history_value
) > linelength
)
711 linelength
= strlen (history_value
) + 1;
712 linebuffer
= (char *) xrealloc (linebuffer
, linelength
);
714 strcpy (linebuffer
, history_value
);
715 p
= linebuffer
+ strlen (linebuffer
);
716 free (history_value
);
720 /* If we just got an empty line, and that is supposed
721 to repeat the previous command, return the value in the
723 if (repeat
&& p
== linebuffer
&& *p
!= '\\')
725 command_handler (line
);
726 display_gdb_prompt (0);
730 for (p1
= linebuffer
; *p1
== ' ' || *p1
== '\t'; p1
++);
733 command_handler (line
);
734 display_gdb_prompt (0);
740 /* Add line to history if appropriate. */
741 if (instream
== stdin
742 && ISATTY (stdin
) && *linebuffer
)
743 add_history (linebuffer
);
745 /* Note: lines consisting solely of comments are added to the command
746 history. This is useful when you type a command, and then
747 realize you don't want to execute it quite yet. You can comment
748 out the command and then later fetch it from the value history
749 and remove the '#'. The kill ring is probably better, but some
750 people are in the habit of commenting things out. */
752 *p1
= '\0'; /* Found a comment. */
754 /* Save into global buffer if appropriate. */
757 if (linelength
> linesize
)
759 line
= xrealloc (line
, linelength
);
760 linesize
= linelength
;
762 strcpy (line
, linebuffer
);
765 command_handler (line
);
766 display_gdb_prompt (0);
771 command_handler (linebuffer
);
772 display_gdb_prompt (0);
776 /* Does reading of input from terminal w/o the editing features
777 provided by the readline library. */
779 /* NOTE: 1999-04-30 Asynchronous version of gdb_readline. gdb_readline
780 will become obsolete when the event loop is made the default
781 execution for gdb. */
783 gdb_readline2 (gdb_client_data client_data
)
788 int result_size
= 80;
789 static int done_once
= 0;
791 /* Unbuffer the input stream, so that, later on, the calls to fgetc
792 fetch only one char at the time from the stream. The fgetc's will
793 get up to the first newline, but there may be more chars in the
794 stream after '\n'. If we buffer the input and fgetc drains the
795 stream, getting stuff beyond the newline as well, a select, done
796 afterwards will not trigger. */
797 if (!done_once
&& !ISATTY (instream
))
799 setbuf (instream
, NULL
);
803 result
= (char *) xmalloc (result_size
);
805 /* We still need the while loop here, even though it would seem
806 obvious to invoke gdb_readline2 at every character entered. If
807 not using the readline library, the terminal is in cooked mode,
808 which sends the characters all at once. Poll will notice that the
809 input fd has changed state only after enter is pressed. At this
810 point we still need to fetch all the chars entered. */
814 /* Read from stdin if we are executing a user defined command.
815 This is the right thing for prompt_for_continue, at least. */
816 c
= fgetc (instream
? instream
: stdin
);
821 /* The last line does not end with a newline. Return it, and
822 if we are called again fgetc will still return EOF and
823 we'll return NULL then. */
826 (*input_handler
) (0);
830 #ifndef CRLF_SOURCE_FILES
834 if (input_index
> 0 && result
[input_index
- 1] == '\r')
840 result
[input_index
++] = c
;
841 while (input_index
>= result_size
)
844 result
= (char *) xrealloc (result
, result_size
);
848 result
[input_index
++] = '\0';
849 (*input_handler
) (result
);
853 /* Initialization of signal handlers and tokens. There is a function
854 handle_sig* for each of the signals GDB cares about. Specifically:
855 SIGINT, SIGFPE, SIGQUIT, SIGTSTP, SIGHUP, SIGWINCH. These
856 functions are the actual signal handlers associated to the signals
857 via calls to signal(). The only job for these functions is to
858 enqueue the appropriate event/procedure with the event loop. Such
859 procedures are the old signal handlers. The event loop will take
860 care of invoking the queued procedures to perform the usual tasks
861 associated with the reception of the signal. */
862 /* NOTE: 1999-04-30 This is the asynchronous version of init_signals.
863 init_signals will become obsolete as we move to have to event loop
864 as the default for gdb. */
866 async_init_signals (void)
868 signal (SIGINT
, handle_sigint
);
870 create_async_signal_handler (async_request_quit
, NULL
);
872 /* If SIGTRAP was set to SIG_IGN, then the SIG_IGN will get passed
873 to the inferior and breakpoints will be ignored. */
875 signal (SIGTRAP
, SIG_DFL
);
878 /* If we initialize SIGQUIT to SIG_IGN, then the SIG_IGN will get
879 passed to the inferior, which we don't want. It would be
880 possible to do a "signal (SIGQUIT, SIG_DFL)" after we fork, but
881 on BSD4.3 systems using vfork, that can affect the
882 GDB process as well as the inferior (the signal handling tables
883 might be in memory, shared between the two). Since we establish
884 a handler for SIGQUIT, when we call exec it will set the signal
885 to SIG_DFL for us. */
886 signal (SIGQUIT
, handle_sigquit
);
888 create_async_signal_handler (async_do_nothing
, NULL
);
890 if (signal (SIGHUP
, handle_sighup
) != SIG_IGN
)
892 create_async_signal_handler (async_disconnect
, NULL
);
895 create_async_signal_handler (async_do_nothing
, NULL
);
897 signal (SIGFPE
, handle_sigfpe
);
899 create_async_signal_handler (async_float_handler
, NULL
);
901 #if defined(SIGWINCH) && defined(SIGWINCH_HANDLER)
902 signal (SIGWINCH
, handle_sigwinch
);
904 create_async_signal_handler (SIGWINCH_HANDLER
, NULL
);
908 create_async_signal_handler (async_stop_sig
, NULL
);
914 mark_async_signal_handler_wrapper (PTR token
)
916 mark_async_signal_handler ((struct async_signal_handler
*) token
);
919 /* Tell the event loop what to do if SIGINT is received.
920 See event-signal.c. */
922 handle_sigint (int sig
)
924 signal (sig
, handle_sigint
);
926 /* If immediate_quit is set, we go ahead and process the SIGINT right
927 away, even if we usually would defer this to the event loop. The
928 assumption here is that it is safe to process ^C immediately if
929 immediate_quit is set. If we didn't, SIGINT would be really
930 processed only the next time through the event loop. To get to
931 that point, though, the command that we want to interrupt needs to
932 finish first, which is unacceptable. */
934 async_request_quit (0);
936 /* If immediate quit is not set, we process SIGINT the next time
937 through the loop, which is fine. */
938 mark_async_signal_handler_wrapper (sigint_token
);
941 /* Do the quit. All the checks have been done by the caller. */
943 async_request_quit (gdb_client_data arg
)
953 /* Tell the event loop what to do if SIGQUIT is received.
954 See event-signal.c. */
956 handle_sigquit (int sig
)
958 mark_async_signal_handler_wrapper (sigquit_token
);
959 signal (sig
, handle_sigquit
);
962 /* Called by the event loop in response to a SIGQUIT. */
964 async_do_nothing (gdb_client_data arg
)
966 /* Empty function body. */
970 /* Tell the event loop what to do if SIGHUP is received.
971 See event-signal.c. */
976 mark_async_signal_handler_wrapper (sighup_token
);
977 signal (sig
, handle_sighup
);
980 /* Called by the event loop to process a SIGHUP */
982 async_disconnect (gdb_client_data arg
)
984 catch_errors (quit_cover
, NULL
,
985 "Could not kill the program being debugged",
987 signal (SIGHUP
, SIG_DFL
); /*FIXME: ??????????? */
988 kill (getpid (), SIGHUP
);
994 handle_stop_sig (int sig
)
996 mark_async_signal_handler_wrapper (sigtstp_token
);
997 signal (sig
, handle_stop_sig
);
1001 async_stop_sig (gdb_client_data arg
)
1003 char *prompt
= get_prompt ();
1004 #if STOP_SIGNAL == SIGTSTP
1005 signal (SIGTSTP
, SIG_DFL
);
1007 kill (getpid (), SIGTSTP
);
1008 signal (SIGTSTP
, handle_stop_sig
);
1010 signal (STOP_SIGNAL
, handle_stop_sig
);
1012 printf_unfiltered ("%s", prompt
);
1013 gdb_flush (gdb_stdout
);
1015 /* Forget about any previous command -- null line now will do nothing. */
1018 #endif /* STOP_SIGNAL */
1020 /* Tell the event loop what to do if SIGFPE is received.
1021 See event-signal.c. */
1023 handle_sigfpe (int sig
)
1025 mark_async_signal_handler_wrapper (sigfpe_token
);
1026 signal (sig
, handle_sigfpe
);
1029 /* Event loop will call this functin to process a SIGFPE. */
1031 async_float_handler (gdb_client_data arg
)
1033 /* This message is based on ANSI C, section 4.7. Note that integer
1034 divide by zero causes this, so "float" is a misnomer. */
1035 error ("Erroneous arithmetic operation.");
1038 /* Tell the event loop what to do if SIGWINCH is received.
1039 See event-signal.c. */
1040 #if defined(SIGWINCH) && defined(SIGWINCH_HANDLER)
1042 handle_sigwinch (int sig
)
1044 mark_async_signal_handler_wrapper (sigwinch_token
);
1045 signal (sig
, handle_sigwinch
);
1050 /* Called by do_setshow_command. */
1053 set_async_editing_command (char *args
, int from_tty
, struct cmd_list_element
*c
)
1055 change_line_handler ();
1058 /* Called by do_setshow_command. */
1061 set_async_annotation_level (char *args
, int from_tty
, struct cmd_list_element
*c
)
1063 change_annotation_level ();
1066 /* Called by do_setshow_command. */
1069 set_async_prompt (char *args
, int from_tty
, struct cmd_list_element
*c
)
1071 PROMPT (0) = savestring (new_async_prompt
, strlen (new_async_prompt
));
1074 /* Set things up for readline to be invoked via the alternate
1075 interface, i.e. via a callback function (rl_callback_read_char),
1076 and hook up instream to the event loop. */
1078 _initialize_event_loop (void)
1082 /* When a character is detected on instream by select or poll,
1083 readline will be invoked via this callback function. */
1084 call_readline
= rl_callback_read_char_wrapper
;
1086 /* When readline has read an end-of-line character, it passes
1087 the complete line to gdb for processing. command_line_handler
1088 is the function that does this. */
1089 input_handler
= command_line_handler
;
1091 /* Tell readline to use the same input stream that gdb uses. */
1092 rl_instream
= instream
;
1094 /* Get a file descriptor for the input stream, so that we can
1095 register it with the event loop. */
1096 input_fd
= fileno (instream
);
1098 /* Tell gdb to use the cli_command_loop as the main loop. */
1099 command_loop_hook
= cli_command_loop
;
1101 /* Now we need to create the event sources for the input file
1103 /* At this point in time, this is the only event source that we
1104 register with the even loop. Another source is going to be
1105 the target program (inferior), but that must be registered
1106 only when it actually exists (I.e. after we say 'run' or
1107 after we connect to a remote target. */
1108 add_file_handler (input_fd
, stdin_event_handler
, 0);
1110 /* Tell gdb that we will be using the readline library. This
1111 could be overwritten by a command in .gdbinit like 'set
1112 editing on' or 'off'. */
1113 async_command_editing_p
= 1;