1 /* Top level stuff for GDB, the GNU debugger.
3 Copyright (C) 1999-2014 Free Software Foundation, Inc.
5 Written by Elena Zannoni <ezannoni@cygnus.com> of Cygnus Solutions.
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 #include "terminal.h" /* for job_control */
28 #include "event-loop.h"
29 #include "event-top.h"
32 #include "cli/cli-script.h" /* for reset_command_nest_depth */
34 #include "gdbthread.h"
36 #include "continuations.h"
37 #include "gdbcmd.h" /* for dont_repeat() */
41 /* readline include files. */
42 #include "readline/readline.h"
43 #include "readline/history.h"
45 /* readline defines this. */
48 static void rl_callback_read_char_wrapper (gdb_client_data client_data);
49 static void command_line_handler (char *rl);
50 static void change_line_handler (void);
51 static void command_handler (char *command);
52 static char *top_level_prompt (void);
54 /* Signal handlers. */
56 static void handle_sigquit (int sig);
59 static void handle_sighup (int sig);
61 static void handle_sigfpe (int sig);
63 /* Functions to be invoked by the event loop in response to
65 #if defined (SIGQUIT) || defined (SIGHUP)
66 static void async_do_nothing (gdb_client_data);
69 static void async_disconnect (gdb_client_data);
71 static void async_float_handler (gdb_client_data);
73 static void async_stop_sig (gdb_client_data);
75 static void async_sigterm_handler (gdb_client_data arg);
77 /* Readline offers an alternate interface, via callback
78 functions. These are all included in the file callback.c in the
79 readline distribution. This file provides (mainly) a function, which
80 the event loop uses as callback (i.e. event handler) whenever an event
81 is detected on the standard input file descriptor.
82 readline_callback_read_char is called (by the GDB event loop) whenever
83 there is a new character ready on the input stream. This function
84 incrementally builds a buffer internal to readline where it
85 accumulates the line read up to the point of invocation. In the
86 special case in which the character read is newline, the function
87 invokes a GDB supplied callback routine, which does the processing of
88 a full command line. This latter routine is the asynchronous analog
89 of the old command_line_input in gdb. Instead of invoking (and waiting
90 for) readline to read the command line and pass it back to
91 command_loop for processing, the new command_line_handler function has
92 the command line already available as its parameter. INPUT_HANDLER is
93 to be set to the function that readline will invoke when a complete
94 line of input is ready. CALL_READLINE is to be set to the function
95 that readline offers as callback to the event_loop. */
97 void (*input_handler) (char *);
98 void (*call_readline) (gdb_client_data);
100 /* Important variables for the event loop. */
102 /* This is used to determine if GDB is using the readline library or
103 its own simplified form of readline. It is used by the asynchronous
104 form of the set editing command.
105 ezannoni: as of 1999-04-29 I expect that this
106 variable will not be used after gdb is changed to use the event
107 loop as default engine, and event-top.c is merged into top.c. */
108 int async_command_editing_p;
110 /* This is the annotation suffix that will be used when the
111 annotation_level is 2. */
112 char *async_annotation_suffix;
114 /* This is used to display the notification of the completion of an
115 asynchronous execution command. */
116 int exec_done_display_p = 0;
118 /* This is the file descriptor for the input stream that GDB uses to
119 read commands from. */
122 /* Signal handling variables. */
123 /* Each of these is a pointer to a function that the event loop will
124 invoke if the corresponding signal has received. The real signal
125 handlers mark these functions as ready to be executed and the event
126 loop, in a later iteration, calls them. See the function
127 invoke_async_signal_handler. */
128 static struct async_signal_handler *sigint_token;
130 static struct async_signal_handler *sighup_token;
133 static struct async_signal_handler *sigquit_token;
135 static struct async_signal_handler *sigfpe_token;
137 static struct async_signal_handler *sigtstp_token;
139 static struct async_signal_handler *async_sigterm_token;
141 /* Structure to save a partially entered command. This is used when
142 the user types '\' at the end of a command line. This is necessary
143 because each line of input is handled by a different call to
144 command_line_handler, and normally there is no state retained
145 between different calls. */
146 static int more_to_come = 0;
148 struct readline_input_state
151 char *linebuffer_ptr;
153 readline_input_state;
155 /* This hook is called by rl_callback_read_char_wrapper after each
156 character is processed. */
157 void (*after_char_processing_hook) (void);
160 /* Wrapper function for calling into the readline library. The event
161 loop expects the callback function to have a paramter, while
162 readline expects none. */
164 rl_callback_read_char_wrapper (gdb_client_data client_data)
166 rl_callback_read_char ();
167 if (after_char_processing_hook)
168 (*after_char_processing_hook) ();
171 /* Initialize all the necessary variables, start the event loop,
172 register readline, and stdin, start the loop. The DATA is the
173 interpreter data cookie, ignored for now. */
176 cli_command_loop (void *data)
178 display_gdb_prompt (0);
180 /* Now it's time to start the event loop. */
184 /* Change the function to be invoked every time there is a character
185 ready on stdin. This is used when the user sets the editing off,
186 therefore bypassing readline, and letting gdb handle the input
187 itself, via gdb_readline2. Also it is used in the opposite case in
188 which the user sets editing on again, by restoring readline
189 handling of the input. */
191 change_line_handler (void)
193 /* NOTE: this operates on input_fd, not instream. If we are reading
194 commands from a file, instream will point to the file. However in
195 async mode, we always read commands from a file with editing
196 off. This means that the 'set editing on/off' will have effect
197 only on the interactive session. */
199 if (async_command_editing_p)
201 /* Turn on editing by using readline. */
202 call_readline = rl_callback_read_char_wrapper;
203 input_handler = command_line_handler;
207 /* Turn off editing by using gdb_readline2. */
208 rl_callback_handler_remove ();
209 call_readline = gdb_readline2;
211 /* Set up the command handler as well, in case we are called as
212 first thing from .gdbinit. */
213 input_handler = command_line_handler;
217 /* Displays the prompt. If the argument NEW_PROMPT is NULL, the
218 prompt that is displayed is the current top level prompt.
219 Otherwise, it displays whatever NEW_PROMPT is as a local/secondary
222 This is used after each gdb command has completed, and in the
225 1. When the user enters a command line which is ended by '\'
226 indicating that the command will continue on the next line. In
227 that case the prompt that is displayed is the empty string.
229 2. When the user is entering 'commands' for a breakpoint, or
230 actions for a tracepoint. In this case the prompt will be '>'
232 3. On prompting for pagination. */
235 display_gdb_prompt (char *new_prompt)
237 char *actual_gdb_prompt = NULL;
238 struct cleanup *old_chain;
240 annotate_display_prompt ();
242 /* Reset the nesting depth used when trace-commands is set. */
243 reset_command_nest_depth ();
245 old_chain = make_cleanup (free_current_contents, &actual_gdb_prompt);
247 /* Do not call the python hook on an explicit prompt change as
248 passed to this function, as this forms a secondary/local prompt,
249 IE, displayed but not set. */
254 /* This is to trick readline into not trying to display the
255 prompt. Even though we display the prompt using this
256 function, readline still tries to do its own display if
257 we don't call rl_callback_handler_install and
258 rl_callback_handler_remove (which readline detects
259 because a global variable is not set). If readline did
260 that, it could mess up gdb signal handlers for SIGINT.
261 Readline assumes that between calls to rl_set_signals and
262 rl_clear_signals gdb doesn't do anything with the signal
263 handlers. Well, that's not the case, because when the
264 target executes we change the SIGINT signal handler. If
265 we allowed readline to display the prompt, the signal
266 handler change would happen exactly between the calls to
267 the above two functions. Calling
268 rl_callback_handler_remove(), does the job. */
270 rl_callback_handler_remove ();
271 do_cleanups (old_chain);
276 /* Display the top level prompt. */
277 actual_gdb_prompt = top_level_prompt ();
281 actual_gdb_prompt = xstrdup (new_prompt);
283 if (async_command_editing_p)
285 rl_callback_handler_remove ();
286 rl_callback_handler_install (actual_gdb_prompt, input_handler);
288 /* new_prompt at this point can be the top of the stack or the one
289 passed in. It can't be NULL. */
292 /* Don't use a _filtered function here. It causes the assumed
293 character position to be off, since the newline we read from
294 the user is not accounted for. */
295 fputs_unfiltered (actual_gdb_prompt, gdb_stdout);
296 gdb_flush (gdb_stdout);
299 do_cleanups (old_chain);
302 /* Return the top level prompt, as specified by "set prompt", possibly
303 overriden by the python gdb.prompt_hook hook, and then composed
304 with the prompt prefix and suffix (annotations). The caller is
305 responsible for freeing the returned string. */
308 top_level_prompt (void)
313 char *composed_prompt;
314 size_t prompt_length;
316 /* Give observers a chance of changing the prompt. E.g., the python
317 `gdb.prompt_hook' is installed as an observer. */
318 observer_notify_before_prompt (get_prompt ());
320 prompt = xstrdup (get_prompt ());
322 if (annotation_level >= 2)
324 /* Prefix needs to have new line at end. */
325 prefix = (char *) alloca (strlen (async_annotation_suffix) + 10);
326 strcpy (prefix, "\n\032\032pre-");
327 strcat (prefix, async_annotation_suffix);
328 strcat (prefix, "\n");
330 /* Suffix needs to have a new line at end and \032 \032 at
332 suffix = (char *) alloca (strlen (async_annotation_suffix) + 6);
333 strcpy (suffix, "\n\032\032");
334 strcat (suffix, async_annotation_suffix);
335 strcat (suffix, "\n");
343 prompt_length = strlen (prefix) + strlen (prompt) + strlen (suffix);
344 composed_prompt = xmalloc (prompt_length + 1);
346 strcpy (composed_prompt, prefix);
347 strcat (composed_prompt, prompt);
348 strcat (composed_prompt, suffix);
352 return composed_prompt;
355 /* When there is an event ready on the stdin file desriptor, instead
356 of calling readline directly throught the callback function, or
357 instead of calling gdb_readline2, give gdb a chance to detect
358 errors and do something. */
360 stdin_event_handler (int error, gdb_client_data client_data)
364 printf_unfiltered (_("error detected on stdin\n"));
365 delete_file_handler (input_fd);
366 discard_all_continuations ();
367 discard_all_intermediate_continuations ();
368 /* If stdin died, we may as well kill gdb. */
369 quit_command ((char *) 0, stdin == instream);
372 (*call_readline) (client_data);
375 /* Re-enable stdin after the end of an execution command in
376 synchronous mode, or after an error from the target, and we aborted
377 the exec operation. */
380 async_enable_stdin (void)
384 /* See NOTE in async_disable_stdin(). */
385 /* FIXME: cagney/1999-09-27: Call this before clearing
386 sync_execution. Current target_terminal_ours() implementations
387 check for sync_execution before switching the terminal. */
388 target_terminal_ours ();
393 /* Disable reads from stdin (the console) marking the command as
397 async_disable_stdin (void)
403 /* Handles a gdb command. This function is called by
404 command_line_handler, which has processed one or more input lines
406 /* NOTE: 1999-04-30 This is the asynchronous version of the command_loop
407 function. The command_loop function will be obsolete when we
408 switch to use the event loop at every execution of gdb. */
410 command_handler (char *command)
412 int stdin_is_tty = ISATTY (stdin);
413 struct cleanup *stat_chain;
416 if (instream == stdin && stdin_is_tty)
417 reinitialize_more_filter ();
419 /* If readline returned a NULL command, it means that the connection
420 with the terminal is gone. This happens at the end of a
421 testsuite run, after Expect has hung up but GDB is still alive.
422 In such a case, we just quit gdb killing the inferior program
426 printf_unfiltered ("quit\n");
427 execute_command ("quit", stdin == instream);
430 stat_chain = make_command_stats_cleanup (1);
432 execute_command (command, instream == stdin);
434 /* Do any commands attached to breakpoint we stopped at. */
435 bpstat_do_actions ();
437 do_cleanups (stat_chain);
440 /* Handle a complete line of input. This is called by the callback
441 mechanism within the readline library. Deal with incomplete
442 commands as well, by saving the partial input in a global
445 /* NOTE: 1999-04-30 This is the asynchronous version of the
446 command_line_input function; command_line_input will become
447 obsolete once we use the event loop as the default mechanism in
450 command_line_handler (char *rl)
452 static char *linebuffer = 0;
453 static unsigned linelength = 0;
457 int repeat = (instream == stdin);
459 if (annotation_level > 1 && instream == stdin)
461 printf_unfiltered (("\n\032\032post-"));
462 puts_unfiltered (async_annotation_suffix);
463 printf_unfiltered (("\n"));
469 linebuffer = (char *) xmalloc (linelength);
470 linebuffer[0] = '\0';
477 strcpy (linebuffer, readline_input_state.linebuffer);
478 p = readline_input_state.linebuffer_ptr;
479 xfree (readline_input_state.linebuffer);
485 signal (STOP_SIGNAL, handle_stop_sig);
488 /* Make sure that all output has been output. Some machines may let
489 you get away with leaving out some of the gdb_flush, but not
492 gdb_flush (gdb_stdout);
493 gdb_flush (gdb_stderr);
495 if (source_file_name != NULL)
496 ++source_line_number;
498 /* If we are in this case, then command_handler will call quit
499 and exit from gdb. */
500 if (!rl || rl == (char *) EOF)
505 if (strlen (rl) + 1 + (p - linebuffer) > linelength)
507 linelength = strlen (rl) + 1 + (p - linebuffer);
508 nline = (char *) xrealloc (linebuffer, linelength);
509 p += nline - linebuffer;
513 /* Copy line. Don't copy null at end. (Leaves line alone
514 if this was just a newline). */
518 xfree (rl); /* Allocated in readline. */
520 if (p > linebuffer && *(p - 1) == '\\')
523 p--; /* Put on top of '\'. */
525 readline_input_state.linebuffer = xstrdup (linebuffer);
526 readline_input_state.linebuffer_ptr = p;
528 /* We will not invoke a execute_command if there is more
529 input expected to complete the command. So, we need to
530 print an empty prompt here. */
532 display_gdb_prompt ("");
538 signal (STOP_SIGNAL, SIG_DFL);
541 #define SERVER_COMMAND_LENGTH 7
543 (p - linebuffer > SERVER_COMMAND_LENGTH)
544 && strncmp (linebuffer, "server ", SERVER_COMMAND_LENGTH) == 0;
547 /* Note that we don't set `line'. Between this and the check in
548 dont_repeat, this insures that repeating will still do the
551 command_handler (linebuffer + SERVER_COMMAND_LENGTH);
552 display_gdb_prompt (0);
556 /* Do history expansion if that is wished. */
557 if (history_expansion_p && instream == stdin
558 && ISATTY (instream))
563 *p = '\0'; /* Insert null now. */
564 expanded = history_expand (linebuffer, &history_value);
567 /* Print the changes. */
568 printf_unfiltered ("%s\n", history_value);
570 /* If there was an error, call this function again. */
573 xfree (history_value);
576 if (strlen (history_value) > linelength)
578 linelength = strlen (history_value) + 1;
579 linebuffer = (char *) xrealloc (linebuffer, linelength);
581 strcpy (linebuffer, history_value);
582 p = linebuffer + strlen (linebuffer);
584 xfree (history_value);
587 /* If we just got an empty line, and that is supposed to repeat the
588 previous command, return the value in the global buffer. */
589 if (repeat && p == linebuffer && *p != '\\')
591 command_handler (saved_command_line);
592 display_gdb_prompt (0);
596 for (p1 = linebuffer; *p1 == ' ' || *p1 == '\t'; p1++);
599 command_handler (saved_command_line);
600 display_gdb_prompt (0);
606 /* Add line to history if appropriate. */
607 if (*linebuffer && input_from_terminal_p ())
608 add_history (linebuffer);
610 /* Note: lines consisting solely of comments are added to the command
611 history. This is useful when you type a command, and then
612 realize you don't want to execute it quite yet. You can comment
613 out the command and then later fetch it from the value history
614 and remove the '#'. The kill ring is probably better, but some
615 people are in the habit of commenting things out. */
617 *p1 = '\0'; /* Found a comment. */
619 /* Save into global buffer if appropriate. */
622 if (linelength > saved_command_line_size)
624 saved_command_line = xrealloc (saved_command_line, linelength);
625 saved_command_line_size = linelength;
627 strcpy (saved_command_line, linebuffer);
630 command_handler (saved_command_line);
631 display_gdb_prompt (0);
636 command_handler (linebuffer);
637 display_gdb_prompt (0);
641 /* Does reading of input from terminal w/o the editing features
642 provided by the readline library. */
644 /* NOTE: 1999-04-30 Asynchronous version of gdb_readline; gdb_readline
645 will become obsolete when the event loop is made the default
646 execution for gdb. */
648 gdb_readline2 (gdb_client_data client_data)
653 int result_size = 80;
654 static int done_once = 0;
656 /* Unbuffer the input stream, so that, later on, the calls to fgetc
657 fetch only one char at the time from the stream. The fgetc's will
658 get up to the first newline, but there may be more chars in the
659 stream after '\n'. If we buffer the input and fgetc drains the
660 stream, getting stuff beyond the newline as well, a select, done
661 afterwards will not trigger. */
662 if (!done_once && !ISATTY (instream))
664 setbuf (instream, NULL);
668 result = (char *) xmalloc (result_size);
670 /* We still need the while loop here, even though it would seem
671 obvious to invoke gdb_readline2 at every character entered. If
672 not using the readline library, the terminal is in cooked mode,
673 which sends the characters all at once. Poll will notice that the
674 input fd has changed state only after enter is pressed. At this
675 point we still need to fetch all the chars entered. */
679 /* Read from stdin if we are executing a user defined command.
680 This is the right thing for prompt_for_continue, at least. */
681 c = fgetc (instream ? instream : stdin);
686 /* The last line does not end with a newline. Return it,
687 and if we are called again fgetc will still return EOF
688 and we'll return NULL then. */
691 (*input_handler) (0);
697 if (input_index > 0 && result[input_index - 1] == '\r')
702 result[input_index++] = c;
703 while (input_index >= result_size)
706 result = (char *) xrealloc (result, result_size);
710 result[input_index++] = '\0';
711 (*input_handler) (result);
715 /* Initialization of signal handlers and tokens. There is a function
716 handle_sig* for each of the signals GDB cares about. Specifically:
717 SIGINT, SIGFPE, SIGQUIT, SIGTSTP, SIGHUP, SIGWINCH. These
718 functions are the actual signal handlers associated to the signals
719 via calls to signal(). The only job for these functions is to
720 enqueue the appropriate event/procedure with the event loop. Such
721 procedures are the old signal handlers. The event loop will take
722 care of invoking the queued procedures to perform the usual tasks
723 associated with the reception of the signal. */
724 /* NOTE: 1999-04-30 This is the asynchronous version of init_signals.
725 init_signals will become obsolete as we move to have to event loop
726 as the default for gdb. */
728 async_init_signals (void)
730 signal (SIGINT, handle_sigint);
732 create_async_signal_handler (async_request_quit, NULL);
733 signal (SIGTERM, handle_sigterm);
735 = create_async_signal_handler (async_sigterm_handler, NULL);
737 /* If SIGTRAP was set to SIG_IGN, then the SIG_IGN will get passed
738 to the inferior and breakpoints will be ignored. */
740 signal (SIGTRAP, SIG_DFL);
744 /* If we initialize SIGQUIT to SIG_IGN, then the SIG_IGN will get
745 passed to the inferior, which we don't want. It would be
746 possible to do a "signal (SIGQUIT, SIG_DFL)" after we fork, but
747 on BSD4.3 systems using vfork, that can affect the
748 GDB process as well as the inferior (the signal handling tables
749 might be in memory, shared between the two). Since we establish
750 a handler for SIGQUIT, when we call exec it will set the signal
751 to SIG_DFL for us. */
752 signal (SIGQUIT, handle_sigquit);
754 create_async_signal_handler (async_do_nothing, NULL);
757 if (signal (SIGHUP, handle_sighup) != SIG_IGN)
759 create_async_signal_handler (async_disconnect, NULL);
762 create_async_signal_handler (async_do_nothing, NULL);
764 signal (SIGFPE, handle_sigfpe);
766 create_async_signal_handler (async_float_handler, NULL);
770 create_async_signal_handler (async_stop_sig, NULL);
774 /* Tell the event loop what to do if SIGINT is received.
775 See event-signal.c. */
777 handle_sigint (int sig)
779 signal (sig, handle_sigint);
781 /* We could be running in a loop reading in symfiles or something so
782 it may be quite a while before we get back to the event loop. So
783 set quit_flag to 1 here. Then if QUIT is called before we get to
784 the event loop, we will unwind as expected. */
788 /* If immediate_quit is set, we go ahead and process the SIGINT right
789 away, even if we usually would defer this to the event loop. The
790 assumption here is that it is safe to process ^C immediately if
791 immediate_quit is set. If we didn't, SIGINT would be really
792 processed only the next time through the event loop. To get to
793 that point, though, the command that we want to interrupt needs to
794 finish first, which is unacceptable. If immediate quit is not set,
795 we process SIGINT the next time through the loop, which is fine. */
796 gdb_call_async_signal_handler (sigint_token, immediate_quit);
799 /* Handle GDB exit upon receiving SIGTERM if target_can_async_p (). */
802 async_sigterm_handler (gdb_client_data arg)
804 quit_force (NULL, stdin == instream);
808 volatile int sync_quit_force_run;
810 /* Quit GDB if SIGTERM is received.
811 GDB would quit anyway, but this way it will clean up properly. */
813 handle_sigterm (int sig)
815 signal (sig, handle_sigterm);
817 /* Call quit_force in a signal safe way.
818 quit_force itself is not signal safe. */
819 if (target_can_async_p ())
820 mark_async_signal_handler (async_sigterm_token);
823 sync_quit_force_run = 1;
828 /* Do the quit. All the checks have been done by the caller. */
830 async_request_quit (gdb_client_data arg)
832 /* If the quit_flag has gotten reset back to 0 by the time we get
833 back here, that means that an exception was thrown to unwind the
834 current command before we got back to the event loop. So there
835 is no reason to call quit again here. */
837 if (check_quit_flag ())
842 /* Tell the event loop what to do if SIGQUIT is received.
843 See event-signal.c. */
845 handle_sigquit (int sig)
847 mark_async_signal_handler (sigquit_token);
848 signal (sig, handle_sigquit);
852 #if defined (SIGQUIT) || defined (SIGHUP)
853 /* Called by the event loop in response to a SIGQUIT or an
856 async_do_nothing (gdb_client_data arg)
858 /* Empty function body. */
863 /* Tell the event loop what to do if SIGHUP is received.
864 See event-signal.c. */
866 handle_sighup (int sig)
868 mark_async_signal_handler (sighup_token);
869 signal (sig, handle_sighup);
872 /* Called by the event loop to process a SIGHUP. */
874 async_disconnect (gdb_client_data arg)
876 volatile struct gdb_exception exception;
878 TRY_CATCH (exception, RETURN_MASK_ALL)
883 if (exception.reason < 0)
885 fputs_filtered ("Could not kill the program being debugged",
887 exception_print (gdb_stderr, exception);
890 TRY_CATCH (exception, RETURN_MASK_ALL)
895 signal (SIGHUP, SIG_DFL); /*FIXME: ??????????? */
902 handle_stop_sig (int sig)
904 mark_async_signal_handler (sigtstp_token);
905 signal (sig, handle_stop_sig);
909 async_stop_sig (gdb_client_data arg)
911 char *prompt = get_prompt ();
913 #if STOP_SIGNAL == SIGTSTP
914 signal (SIGTSTP, SIG_DFL);
920 sigprocmask (SIG_SETMASK, &zero, 0);
922 #elif HAVE_SIGSETMASK
926 signal (SIGTSTP, handle_stop_sig);
928 signal (STOP_SIGNAL, handle_stop_sig);
930 printf_unfiltered ("%s", prompt);
931 gdb_flush (gdb_stdout);
933 /* Forget about any previous command -- null line now will do
937 #endif /* STOP_SIGNAL */
939 /* Tell the event loop what to do if SIGFPE is received.
940 See event-signal.c. */
942 handle_sigfpe (int sig)
944 mark_async_signal_handler (sigfpe_token);
945 signal (sig, handle_sigfpe);
948 /* Event loop will call this functin to process a SIGFPE. */
950 async_float_handler (gdb_client_data arg)
952 /* This message is based on ANSI C, section 4.7. Note that integer
953 divide by zero causes this, so "float" is a misnomer. */
954 error (_("Erroneous arithmetic operation."));
958 /* Called by do_setshow_command. */
960 set_async_editing_command (char *args, int from_tty,
961 struct cmd_list_element *c)
963 change_line_handler ();
966 /* Set things up for readline to be invoked via the alternate
967 interface, i.e. via a callback function (rl_callback_read_char),
968 and hook up instream to the event loop. */
970 gdb_setup_readline (void)
972 /* This function is a noop for the sync case. The assumption is
973 that the sync setup is ALL done in gdb_init, and we would only
974 mess it up here. The sync stuff should really go away over
977 gdb_stdout = stdio_fileopen (stdout);
978 gdb_stderr = stderr_fileopen ();
979 gdb_stdlog = gdb_stderr; /* for moment */
980 gdb_stdtarg = gdb_stderr; /* for moment */
981 gdb_stdtargerr = gdb_stderr; /* for moment */
983 /* If the input stream is connected to a terminal, turn on
985 if (ISATTY (instream))
987 /* Tell gdb that we will be using the readline library. This
988 could be overwritten by a command in .gdbinit like 'set
989 editing on' or 'off'. */
990 async_command_editing_p = 1;
992 /* When a character is detected on instream by select or poll,
993 readline will be invoked via this callback function. */
994 call_readline = rl_callback_read_char_wrapper;
998 async_command_editing_p = 0;
999 call_readline = gdb_readline2;
1002 /* When readline has read an end-of-line character, it passes the
1003 complete line to gdb for processing; command_line_handler is the
1004 function that does this. */
1005 input_handler = command_line_handler;
1007 /* Tell readline to use the same input stream that gdb uses. */
1008 rl_instream = instream;
1010 /* Get a file descriptor for the input stream, so that we can
1011 register it with the event loop. */
1012 input_fd = fileno (instream);
1014 /* Now we need to create the event sources for the input file
1016 /* At this point in time, this is the only event source that we
1017 register with the even loop. Another source is going to be the
1018 target program (inferior), but that must be registered only when
1019 it actually exists (I.e. after we say 'run' or after we connect
1020 to a remote target. */
1021 add_file_handler (input_fd, stdin_event_handler, 0);
1024 /* Disable command input through the standard CLI channels. Used in
1025 the suspend proc for interpreters that use the standard gdb readline
1026 interface, like the cli & the mi. */
1028 gdb_disable_readline (void)
1030 /* FIXME - It is too heavyweight to delete and remake these every
1031 time you run an interpreter that needs readline. It is probably
1032 better to have the interpreters cache these, which in turn means
1033 that this needs to be moved into interpreter specific code. */
1036 ui_file_delete (gdb_stdout);
1037 ui_file_delete (gdb_stderr);
1040 gdb_stdtargerr = NULL;
1043 rl_callback_handler_remove ();
1044 delete_file_handler (input_fd);