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
);
416 /* Re-enable stdin after the end of an execution command in
417 synchronous mode, or after an error from the target, and we aborted
418 the exec operation. */
421 async_enable_stdin (void *dummy
)
423 /* See NOTE in async_disable_stdin() */
424 /* FIXME: cagney/1999-09-27: Call this before clearing
425 sync_execution. Current target_terminal_ours() implementations
426 check for sync_execution before switching the terminal. */
427 target_terminal_ours ();
432 /* Disable reads from stdin (the console) marking the command as
436 async_disable_stdin (void)
439 push_prompt ("", "", "");
440 /* FIXME: cagney/1999-09-27: At present this call is technically
441 redundant since infcmd.c and infrun.c both already call
442 target_terminal_inferior(). As the terminal handling (in
443 sync/async mode) is refined, the duplicate calls can be
444 eliminated (Here or in infcmd.c/infrun.c). */
445 target_terminal_inferior ();
446 make_exec_cleanup (async_enable_stdin
, NULL
);
447 make_exec_error_cleanup (async_enable_stdin
, NULL
);
451 /* Handles a gdb command. This function is called by
452 command_line_handler, which has processed one or more input lines
454 /* NOTE: 1999-04-30 This is the asynchronous version of the command_loop
455 function. The command_loop function will be obsolete when we
456 switch to use the event loop at every execution of gdb. */
458 command_handler (char *command
)
460 struct cleanup
*old_chain
;
461 int stdin_is_tty
= ISATTY (stdin
);
462 struct continuation_arg
*arg1
;
463 struct continuation_arg
*arg2
;
464 long time_at_cmd_start
;
466 long space_at_cmd_start
= 0;
468 extern int display_time
;
469 extern int display_space
;
472 extern int insert_mode
;
476 if (instream
== stdin
&& stdin_is_tty
)
477 reinitialize_more_filter ();
478 old_chain
= make_cleanup ((make_cleanup_func
) command_loop_marker
, 0);
483 /* If readline returned a NULL command, it means that the
484 connection with the terminal is gone. This happens at the
485 end of a testsuite run, after Expect has hung up
486 but GDB is still alive. In such a case, we just quit gdb
487 killing the inferior program too. */
489 quit_command ((char *) 0, stdin
== instream
);
491 time_at_cmd_start
= get_run_time ();
496 extern char **environ
;
497 char *lim
= (char *) sbrk (0);
499 space_at_cmd_start
= (long) (lim
- (char *) &environ
);
503 execute_command (command
, instream
== stdin
);
505 /* Set things up for this function to be compete later, once the
506 executin has completed, if we are doing an execution command,
507 otherwise, just go ahead and finish. */
508 if (target_can_async_p () && target_executing
)
511 (struct continuation_arg
*) xmalloc (sizeof (struct continuation_arg
));
513 (struct continuation_arg
*) xmalloc (sizeof (struct continuation_arg
));
516 arg1
->data
= (PTR
) time_at_cmd_start
;
517 arg2
->data
= (PTR
) space_at_cmd_start
;
518 add_continuation (command_line_handler_continuation
, arg1
);
521 /* Do any commands attached to breakpoint we stopped at. Only if we
522 are always running synchronously. Or if we have just executed a
523 command that doesn't start the target. */
524 if (!target_can_async_p () || !target_executing
)
526 bpstat_do_actions (&stop_bpstat
);
527 do_cleanups (old_chain
);
531 long cmd_time
= get_run_time () - time_at_cmd_start
;
533 printf_unfiltered ("Command execution time: %ld.%06ld\n",
534 cmd_time
/ 1000000, cmd_time
% 1000000);
540 extern char **environ
;
541 char *lim
= (char *) sbrk (0);
542 long space_now
= lim
- (char *) &environ
;
543 long space_diff
= space_now
- space_at_cmd_start
;
545 printf_unfiltered ("Space used: %ld (%c%ld for this command)\n",
547 (space_diff
>= 0 ? '+' : '-'),
554 /* Do any commands attached to breakpoint we stopped at. Only if we
555 are always running synchronously. Or if we have just executed a
556 command that doesn't start the target. */
558 command_line_handler_continuation (struct continuation_arg
*arg
)
560 extern int display_time
;
561 extern int display_space
;
563 long time_at_cmd_start
= (long) arg
->data
;
564 long space_at_cmd_start
= (long) arg
->next
->data
;
566 bpstat_do_actions (&stop_bpstat
);
567 /*do_cleanups (old_chain); *//*?????FIXME????? */
571 long cmd_time
= get_run_time () - time_at_cmd_start
;
573 printf_unfiltered ("Command execution time: %ld.%06ld\n",
574 cmd_time
/ 1000000, cmd_time
% 1000000);
579 extern char **environ
;
580 char *lim
= (char *) sbrk (0);
581 long space_now
= lim
- (char *) &environ
;
582 long space_diff
= space_now
- space_at_cmd_start
;
584 printf_unfiltered ("Space used: %ld (%c%ld for this command)\n",
586 (space_diff
>= 0 ? '+' : '-'),
592 /* Handle a complete line of input. This is called by the callback
593 mechanism within the readline library. Deal with incomplete commands
594 as well, by saving the partial input in a global buffer. */
596 /* NOTE: 1999-04-30 This is the asynchronous version of the
597 command_line_input function. command_line_input will become
598 obsolete once we use the event loop as the default mechanism in
601 command_line_handler (char *rl
)
603 static char *linebuffer
= 0;
604 static unsigned linelength
= 0;
613 int repeat
= (instream
== stdin
);
615 if (annotation_level
> 1 && instream
== stdin
)
617 printf_unfiltered ("\n\032\032post-");
618 printf_unfiltered (async_annotation_suffix
);
619 printf_unfiltered ("\n");
625 linebuffer
= (char *) xmalloc (linelength
);
632 strcpy (linebuffer
, readline_input_state
.linebuffer
);
633 p
= readline_input_state
.linebuffer_ptr
;
634 free (readline_input_state
.linebuffer
);
641 signal (STOP_SIGNAL
, handle_stop_sig
);
644 /* Make sure that all output has been output. Some machines may let
645 you get away with leaving out some of the gdb_flush, but not all. */
647 gdb_flush (gdb_stdout
);
648 gdb_flush (gdb_stderr
);
650 if (source_file_name
!= NULL
)
652 ++source_line_number
;
653 sprintf (source_error
,
654 "%s%s:%d: Error in sourced command file:\n",
658 error_pre_print
= source_error
;
661 /* If we are in this case, then command_handler will call quit
662 and exit from gdb. */
663 if (!rl
|| rl
== (char *) EOF
)
668 if (strlen (rl
) + 1 + (p
- linebuffer
) > linelength
)
670 linelength
= strlen (rl
) + 1 + (p
- linebuffer
);
671 nline
= (char *) xrealloc (linebuffer
, linelength
);
672 p
+= nline
- linebuffer
;
676 /* Copy line. Don't copy null at end. (Leaves line alone
677 if this was just a newline) */
681 free (rl
); /* Allocated in readline. */
683 if (*(p
- 1) == '\\')
685 p
--; /* Put on top of '\'. */
689 readline_input_state
.linebuffer
= savestring (linebuffer
,
690 strlen (linebuffer
));
691 readline_input_state
.linebuffer_ptr
= p
;
693 /* We will not invoke a execute_command if there is more
694 input expected to complete the command. So, we need to
695 print an empty prompt here. */
697 push_prompt ("", "", "");
698 display_gdb_prompt (0);
705 signal (STOP_SIGNAL
, SIG_DFL
);
708 #define SERVER_COMMAND_LENGTH 7
710 (p
- linebuffer
> SERVER_COMMAND_LENGTH
)
711 && STREQN (linebuffer
, "server ", SERVER_COMMAND_LENGTH
);
714 /* Note that we don't set `line'. Between this and the check in
715 dont_repeat, this insures that repeating will still do the
718 command_handler (linebuffer
+ SERVER_COMMAND_LENGTH
);
719 display_gdb_prompt (0);
723 /* Do history expansion if that is wished. */
724 if (history_expansion_p
&& instream
== stdin
725 && ISATTY (instream
))
730 *p
= '\0'; /* Insert null now. */
731 expanded
= history_expand (linebuffer
, &history_value
);
734 /* Print the changes. */
735 printf_unfiltered ("%s\n", history_value
);
737 /* If there was an error, call this function again. */
740 free (history_value
);
743 if (strlen (history_value
) > linelength
)
745 linelength
= strlen (history_value
) + 1;
746 linebuffer
= (char *) xrealloc (linebuffer
, linelength
);
748 strcpy (linebuffer
, history_value
);
749 p
= linebuffer
+ strlen (linebuffer
);
750 free (history_value
);
754 /* If we just got an empty line, and that is supposed
755 to repeat the previous command, return the value in the
757 if (repeat
&& p
== linebuffer
&& *p
!= '\\')
759 command_handler (line
);
760 display_gdb_prompt (0);
764 for (p1
= linebuffer
; *p1
== ' ' || *p1
== '\t'; p1
++);
767 command_handler (line
);
768 display_gdb_prompt (0);
774 /* Add line to history if appropriate. */
775 if (instream
== stdin
776 && ISATTY (stdin
) && *linebuffer
)
777 add_history (linebuffer
);
779 /* Note: lines consisting solely of comments are added to the command
780 history. This is useful when you type a command, and then
781 realize you don't want to execute it quite yet. You can comment
782 out the command and then later fetch it from the value history
783 and remove the '#'. The kill ring is probably better, but some
784 people are in the habit of commenting things out. */
786 *p1
= '\0'; /* Found a comment. */
788 /* Save into global buffer if appropriate. */
791 if (linelength
> linesize
)
793 line
= xrealloc (line
, linelength
);
794 linesize
= linelength
;
796 strcpy (line
, linebuffer
);
799 command_handler (line
);
800 display_gdb_prompt (0);
805 command_handler (linebuffer
);
806 display_gdb_prompt (0);
810 /* Does reading of input from terminal w/o the editing features
811 provided by the readline library. */
813 /* NOTE: 1999-04-30 Asynchronous version of gdb_readline. gdb_readline
814 will become obsolete when the event loop is made the default
815 execution for gdb. */
817 gdb_readline2 (gdb_client_data client_data
)
822 int result_size
= 80;
823 static int done_once
= 0;
825 /* Unbuffer the input stream, so that, later on, the calls to fgetc
826 fetch only one char at the time from the stream. The fgetc's will
827 get up to the first newline, but there may be more chars in the
828 stream after '\n'. If we buffer the input and fgetc drains the
829 stream, getting stuff beyond the newline as well, a select, done
830 afterwards will not trigger. */
831 if (!done_once
&& !ISATTY (instream
))
833 setbuf (instream
, NULL
);
837 result
= (char *) xmalloc (result_size
);
839 /* We still need the while loop here, even though it would seem
840 obvious to invoke gdb_readline2 at every character entered. If
841 not using the readline library, the terminal is in cooked mode,
842 which sends the characters all at once. Poll will notice that the
843 input fd has changed state only after enter is pressed. At this
844 point we still need to fetch all the chars entered. */
848 /* Read from stdin if we are executing a user defined command.
849 This is the right thing for prompt_for_continue, at least. */
850 c
= fgetc (instream
? instream
: stdin
);
855 /* The last line does not end with a newline. Return it, and
856 if we are called again fgetc will still return EOF and
857 we'll return NULL then. */
860 (*input_handler
) (0);
864 #ifndef CRLF_SOURCE_FILES
868 if (input_index
> 0 && result
[input_index
- 1] == '\r')
874 result
[input_index
++] = c
;
875 while (input_index
>= result_size
)
878 result
= (char *) xrealloc (result
, result_size
);
882 result
[input_index
++] = '\0';
883 (*input_handler
) (result
);
887 /* Initialization of signal handlers and tokens. There is a function
888 handle_sig* for each of the signals GDB cares about. Specifically:
889 SIGINT, SIGFPE, SIGQUIT, SIGTSTP, SIGHUP, SIGWINCH. These
890 functions are the actual signal handlers associated to the signals
891 via calls to signal(). The only job for these functions is to
892 enqueue the appropriate event/procedure with the event loop. Such
893 procedures are the old signal handlers. The event loop will take
894 care of invoking the queued procedures to perform the usual tasks
895 associated with the reception of the signal. */
896 /* NOTE: 1999-04-30 This is the asynchronous version of init_signals.
897 init_signals will become obsolete as we move to have to event loop
898 as the default for gdb. */
900 async_init_signals (void)
902 signal (SIGINT
, handle_sigint
);
904 create_async_signal_handler (async_request_quit
, NULL
);
906 /* If SIGTRAP was set to SIG_IGN, then the SIG_IGN will get passed
907 to the inferior and breakpoints will be ignored. */
909 signal (SIGTRAP
, SIG_DFL
);
912 /* If we initialize SIGQUIT to SIG_IGN, then the SIG_IGN will get
913 passed to the inferior, which we don't want. It would be
914 possible to do a "signal (SIGQUIT, SIG_DFL)" after we fork, but
915 on BSD4.3 systems using vfork, that can affect the
916 GDB process as well as the inferior (the signal handling tables
917 might be in memory, shared between the two). Since we establish
918 a handler for SIGQUIT, when we call exec it will set the signal
919 to SIG_DFL for us. */
920 signal (SIGQUIT
, handle_sigquit
);
922 create_async_signal_handler (async_do_nothing
, NULL
);
924 if (signal (SIGHUP
, handle_sighup
) != SIG_IGN
)
926 create_async_signal_handler (async_disconnect
, NULL
);
929 create_async_signal_handler (async_do_nothing
, NULL
);
931 signal (SIGFPE
, handle_sigfpe
);
933 create_async_signal_handler (async_float_handler
, NULL
);
935 #if defined(SIGWINCH) && defined(SIGWINCH_HANDLER)
936 signal (SIGWINCH
, handle_sigwinch
);
938 create_async_signal_handler (SIGWINCH_HANDLER
, NULL
);
942 create_async_signal_handler (async_stop_sig
, NULL
);
948 mark_async_signal_handler_wrapper (PTR token
)
950 mark_async_signal_handler ((struct async_signal_handler
*) token
);
953 /* Tell the event loop what to do if SIGINT is received.
954 See event-signal.c. */
956 handle_sigint (int sig
)
958 signal (sig
, handle_sigint
);
960 /* If immediate_quit is set, we go ahead and process the SIGINT right
961 away, even if we usually would defer this to the event loop. The
962 assumption here is that it is safe to process ^C immediately if
963 immediate_quit is set. If we didn't, SIGINT would be really
964 processed only the next time through the event loop. To get to
965 that point, though, the command that we want to interrupt needs to
966 finish first, which is unacceptable. */
968 async_request_quit (0);
970 /* If immediate quit is not set, we process SIGINT the next time
971 through the loop, which is fine. */
972 mark_async_signal_handler_wrapper (sigint_token
);
975 /* Do the quit. All the checks have been done by the caller. */
977 async_request_quit (gdb_client_data arg
)
987 /* Tell the event loop what to do if SIGQUIT is received.
988 See event-signal.c. */
990 handle_sigquit (int sig
)
992 mark_async_signal_handler_wrapper (sigquit_token
);
993 signal (sig
, handle_sigquit
);
996 /* Called by the event loop in response to a SIGQUIT. */
998 async_do_nothing (gdb_client_data arg
)
1000 /* Empty function body. */
1004 /* Tell the event loop what to do if SIGHUP is received.
1005 See event-signal.c. */
1010 mark_async_signal_handler_wrapper (sighup_token
);
1011 signal (sig
, handle_sighup
);
1014 /* Called by the event loop to process a SIGHUP */
1016 async_disconnect (gdb_client_data arg
)
1018 catch_errors (quit_cover
, NULL
,
1019 "Could not kill the program being debugged",
1021 signal (SIGHUP
, SIG_DFL
); /*FIXME: ??????????? */
1022 kill (getpid (), SIGHUP
);
1028 handle_stop_sig (int sig
)
1030 mark_async_signal_handler_wrapper (sigtstp_token
);
1031 signal (sig
, handle_stop_sig
);
1035 async_stop_sig (gdb_client_data arg
)
1037 char *prompt
= get_prompt ();
1038 #if STOP_SIGNAL == SIGTSTP
1039 signal (SIGTSTP
, SIG_DFL
);
1041 kill (getpid (), SIGTSTP
);
1042 signal (SIGTSTP
, handle_stop_sig
);
1044 signal (STOP_SIGNAL
, handle_stop_sig
);
1046 printf_unfiltered ("%s", prompt
);
1047 gdb_flush (gdb_stdout
);
1049 /* Forget about any previous command -- null line now will do nothing. */
1052 #endif /* STOP_SIGNAL */
1054 /* Tell the event loop what to do if SIGFPE is received.
1055 See event-signal.c. */
1057 handle_sigfpe (int sig
)
1059 mark_async_signal_handler_wrapper (sigfpe_token
);
1060 signal (sig
, handle_sigfpe
);
1063 /* Event loop will call this functin to process a SIGFPE. */
1065 async_float_handler (gdb_client_data arg
)
1067 /* This message is based on ANSI C, section 4.7. Note that integer
1068 divide by zero causes this, so "float" is a misnomer. */
1069 error ("Erroneous arithmetic operation.");
1072 /* Tell the event loop what to do if SIGWINCH is received.
1073 See event-signal.c. */
1074 #if defined(SIGWINCH) && defined(SIGWINCH_HANDLER)
1076 handle_sigwinch (int sig
)
1078 mark_async_signal_handler_wrapper (sigwinch_token
);
1079 signal (sig
, handle_sigwinch
);
1084 /* Called by do_setshow_command. */
1087 set_async_editing_command (char *args
, int from_tty
, struct cmd_list_element
*c
)
1089 change_line_handler ();
1092 /* Called by do_setshow_command. */
1095 set_async_annotation_level (char *args
, int from_tty
, struct cmd_list_element
*c
)
1097 change_annotation_level ();
1100 /* Called by do_setshow_command. */
1103 set_async_prompt (char *args
, int from_tty
, struct cmd_list_element
*c
)
1105 PROMPT (0) = savestring (new_async_prompt
, strlen (new_async_prompt
));
1108 /* Set things up for readline to be invoked via the alternate
1109 interface, i.e. via a callback function (rl_callback_read_char),
1110 and hook up instream to the event loop. */
1112 _initialize_event_loop (void)
1116 /* When a character is detected on instream by select or poll,
1117 readline will be invoked via this callback function. */
1118 call_readline
= rl_callback_read_char_wrapper
;
1120 /* When readline has read an end-of-line character, it passes
1121 the complete line to gdb for processing. command_line_handler
1122 is the function that does this. */
1123 input_handler
= command_line_handler
;
1125 /* Tell readline to use the same input stream that gdb uses. */
1126 rl_instream
= instream
;
1128 /* Get a file descriptor for the input stream, so that we can
1129 register it with the event loop. */
1130 input_fd
= fileno (instream
);
1132 /* Tell gdb to use the cli_command_loop as the main loop. */
1133 command_loop_hook
= cli_command_loop
;
1135 /* Now we need to create the event sources for the input file
1137 /* At this point in time, this is the only event source that we
1138 register with the even loop. Another source is going to be
1139 the target program (inferior), but that must be registered
1140 only when it actually exists (I.e. after we say 'run' or
1141 after we connect to a remote target. */
1142 add_file_handler (input_fd
, stdin_event_handler
, 0);
1144 /* Tell gdb that we will be using the readline library. This
1145 could be overwritten by a command in .gdbinit like 'set
1146 editing on' or 'off'. */
1147 async_command_editing_p
= 1;