1 /* Top level stuff for GDB, the GNU debugger.
3 Copyright (C) 1999-2002, 2004-2005, 2007-2012 Free Software
6 Written by Elena Zannoni <ezannoni@cygnus.com> of Cygnus Solutions.
8 This file is part of GDB.
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3 of the License, or
13 (at your option) any later version.
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 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 "exceptions.h"
33 #include "cli/cli-script.h" /* for reset_command_nest_depth */
35 #include "gdbthread.h"
37 #include "continuations.h"
38 #include "gdbcmd.h" /* for dont_repeat() */
40 /* readline include files. */
41 #include "readline/readline.h"
42 #include "readline/history.h"
44 /* readline defines this. */
47 static void rl_callback_read_char_wrapper (gdb_client_data client_data);
48 static void command_line_handler (char *rl);
49 static void change_line_handler (void);
50 static void command_handler (char *command);
51 static char *top_level_prompt (void);
53 /* Signal handlers. */
55 static void handle_sigquit (int sig);
58 static void handle_sighup (int sig);
60 static void handle_sigfpe (int sig);
62 /* Functions to be invoked by the event loop in response to
64 #if defined (SIGQUIT) || defined (SIGHUP)
65 static void async_do_nothing (gdb_client_data);
68 static void async_disconnect (gdb_client_data);
70 static void async_float_handler (gdb_client_data);
72 static void async_stop_sig (gdb_client_data);
75 /* Readline offers an alternate interface, via callback
76 functions. These are all included in the file callback.c in the
77 readline distribution. This file provides (mainly) a function, which
78 the event loop uses as callback (i.e. event handler) whenever an event
79 is detected on the standard input file descriptor.
80 readline_callback_read_char is called (by the GDB event loop) whenever
81 there is a new character ready on the input stream. This function
82 incrementally builds a buffer internal to readline where it
83 accumulates the line read up to the point of invocation. In the
84 special case in which the character read is newline, the function
85 invokes a GDB supplied callback routine, which does the processing of
86 a full command line. This latter routine is the asynchronous analog
87 of the old command_line_input in gdb. Instead of invoking (and waiting
88 for) readline to read the command line and pass it back to
89 command_loop for processing, the new command_line_handler function has
90 the command line already available as its parameter. INPUT_HANDLER is
91 to be set to the function that readline will invoke when a complete
92 line of input is ready. CALL_READLINE is to be set to the function
93 that readline offers as callback to the event_loop. */
95 void (*input_handler) (char *);
96 void (*call_readline) (gdb_client_data);
98 /* Important variables for the event loop. */
100 /* This is used to determine if GDB is using the readline library or
101 its own simplified form of readline. It is used by the asynchronous
102 form of the set editing command.
103 ezannoni: as of 1999-04-29 I expect that this
104 variable will not be used after gdb is changed to use the event
105 loop as default engine, and event-top.c is merged into top.c. */
106 int async_command_editing_p;
108 /* This is the annotation suffix that will be used when the
109 annotation_level is 2. */
110 char *async_annotation_suffix;
112 /* This is used to display the notification of the completion of an
113 asynchronous execution command. */
114 int exec_done_display_p = 0;
116 /* This is the file descriptor for the input stream that GDB uses to
117 read commands from. */
120 /* Signal handling variables. */
121 /* Each of these is a pointer to a function that the event loop will
122 invoke if the corresponding signal has received. The real signal
123 handlers mark these functions as ready to be executed and the event
124 loop, in a later iteration, calls them. See the function
125 invoke_async_signal_handler. */
126 static struct async_signal_handler *sigint_token;
128 static struct async_signal_handler *sighup_token;
131 static struct async_signal_handler *sigquit_token;
133 static struct async_signal_handler *sigfpe_token;
135 static struct async_signal_handler *sigtstp_token;
138 /* Structure to save a partially entered command. This is used when
139 the user types '\' at the end of a command line. This is necessary
140 because each line of input is handled by a different call to
141 command_line_handler, and normally there is no state retained
142 between different calls. */
143 static int more_to_come = 0;
145 struct readline_input_state
148 char *linebuffer_ptr;
150 readline_input_state;
152 /* This hook is called by rl_callback_read_char_wrapper after each
153 character is processed. */
154 void (*after_char_processing_hook) (void);
157 /* Wrapper function for calling into the readline library. The event
158 loop expects the callback function to have a paramter, while
159 readline expects none. */
161 rl_callback_read_char_wrapper (gdb_client_data client_data)
163 rl_callback_read_char ();
164 if (after_char_processing_hook)
165 (*after_char_processing_hook) ();
168 /* Initialize all the necessary variables, start the event loop,
169 register readline, and stdin, start the loop. */
171 cli_command_loop (void)
173 display_gdb_prompt (0);
175 /* Now it's time to start the event loop. */
179 /* Change the function to be invoked every time there is a character
180 ready on stdin. This is used when the user sets the editing off,
181 therefore bypassing readline, and letting gdb handle the input
182 itself, via gdb_readline2. Also it is used in the opposite case in
183 which the user sets editing on again, by restoring readline
184 handling of the input. */
186 change_line_handler (void)
188 /* NOTE: this operates on input_fd, not instream. If we are reading
189 commands from a file, instream will point to the file. However in
190 async mode, we always read commands from a file with editing
191 off. This means that the 'set editing on/off' will have effect
192 only on the interactive session. */
194 if (async_command_editing_p)
196 /* Turn on editing by using readline. */
197 call_readline = rl_callback_read_char_wrapper;
198 input_handler = command_line_handler;
202 /* Turn off editing by using gdb_readline2. */
203 rl_callback_handler_remove ();
204 call_readline = gdb_readline2;
206 /* Set up the command handler as well, in case we are called as
207 first thing from .gdbinit. */
208 input_handler = command_line_handler;
212 /* Displays the prompt. If the argument NEW_PROMPT is NULL, the
213 prompt that is displayed is the current top level prompt.
214 Otherwise, it displays whatever NEW_PROMPT is as a local/secondary
217 This is used after each gdb command has completed, and in the
220 1. When the user enters a command line which is ended by '\'
221 indicating that the command will continue on the next line. In
222 that case the prompt that is displayed is the empty string.
224 2. When the user is entering 'commands' for a breakpoint, or
225 actions for a tracepoint. In this case the prompt will be '>'
227 3. On prompting for pagination. */
230 display_gdb_prompt (char *new_prompt)
232 char *actual_gdb_prompt = NULL;
233 struct cleanup *old_chain;
235 /* Reset the nesting depth used when trace-commands is set. */
236 reset_command_nest_depth ();
238 /* Each interpreter has its own rules on displaying the command
240 if (!current_interp_display_prompt_p ())
243 old_chain = make_cleanup (free_current_contents, &actual_gdb_prompt);
245 /* Do not call the python hook on an explicit prompt change as
246 passed to this function, as this forms a secondary/local prompt,
247 IE, displayed but not set. */
252 /* This is to trick readline into not trying to display the
253 prompt. Even though we display the prompt using this
254 function, readline still tries to do its own display if
255 we don't call rl_callback_handler_install and
256 rl_callback_handler_remove (which readline detects
257 because a global variable is not set). If readline did
258 that, it could mess up gdb signal handlers for SIGINT.
259 Readline assumes that between calls to rl_set_signals and
260 rl_clear_signals gdb doesn't do anything with the signal
261 handlers. Well, that's not the case, because when the
262 target executes we change the SIGINT signal handler. If
263 we allowed readline to display the prompt, the signal
264 handler change would happen exactly between the calls to
265 the above two functions. Calling
266 rl_callback_handler_remove(), does the job. */
268 rl_callback_handler_remove ();
273 /* Display the top level prompt. */
274 actual_gdb_prompt = top_level_prompt ();
278 actual_gdb_prompt = xstrdup (new_prompt);
280 if (async_command_editing_p)
282 rl_callback_handler_remove ();
283 rl_callback_handler_install (actual_gdb_prompt, input_handler);
285 /* new_prompt at this point can be the top of the stack or the one
286 passed in. It can't be NULL. */
289 /* Don't use a _filtered function here. It causes the assumed
290 character position to be off, since the newline we read from
291 the user is not accounted for. */
292 fputs_unfiltered (actual_gdb_prompt, gdb_stdout);
293 gdb_flush (gdb_stdout);
296 do_cleanups (old_chain);
299 /* Return the top level prompt, as specified by "set prompt", possibly
300 overriden by the python gdb.prompt_hook hook, and then composed
301 with the prompt prefix and suffix (annotations). The caller is
302 responsible for freeing the returned string. */
305 top_level_prompt (void)
310 char *composed_prompt;
311 size_t prompt_length;
313 /* Give observers a chance of changing the prompt. E.g., the python
314 `gdb.prompt_hook' is installed as an observer. */
315 observer_notify_before_prompt (get_prompt ());
317 prompt = xstrdup (get_prompt ());
319 if (annotation_level >= 2)
321 /* Prefix needs to have new line at end. */
322 prefix = (char *) alloca (strlen (async_annotation_suffix) + 10);
323 strcpy (prefix, "\n\032\032pre-");
324 strcat (prefix, async_annotation_suffix);
325 strcat (prefix, "\n");
327 /* Suffix needs to have a new line at end and \032 \032 at
329 suffix = (char *) alloca (strlen (async_annotation_suffix) + 6);
330 strcpy (suffix, "\n\032\032");
331 strcat (suffix, async_annotation_suffix);
332 strcat (suffix, "\n");
340 prompt_length = strlen (prefix) + strlen (prompt) + strlen (suffix);
341 composed_prompt = xmalloc (prompt_length + 1);
343 strcpy (composed_prompt, prefix);
344 strcat (composed_prompt, prompt);
345 strcat (composed_prompt, suffix);
349 return composed_prompt;
352 /* When there is an event ready on the stdin file desriptor, instead
353 of calling readline directly throught the callback function, or
354 instead of calling gdb_readline2, give gdb a chance to detect
355 errors and do something. */
357 stdin_event_handler (int error, gdb_client_data client_data)
361 printf_unfiltered (_("error detected on stdin\n"));
362 delete_file_handler (input_fd);
363 discard_all_continuations ();
364 discard_all_intermediate_continuations ();
365 /* If stdin died, we may as well kill gdb. */
366 quit_command ((char *) 0, stdin == instream);
369 (*call_readline) (client_data);
372 /* Re-enable stdin after the end of an execution command in
373 synchronous mode, or after an error from the target, and we aborted
374 the exec operation. */
377 async_enable_stdin (void)
381 /* See NOTE in async_disable_stdin(). */
382 /* FIXME: cagney/1999-09-27: Call this before clearing
383 sync_execution. Current target_terminal_ours() implementations
384 check for sync_execution before switching the terminal. */
385 target_terminal_ours ();
390 /* Disable reads from stdin (the console) marking the command as
394 async_disable_stdin (void)
400 /* Handles a gdb command. This function is called by
401 command_line_handler, which has processed one or more input lines
403 /* NOTE: 1999-04-30 This is the asynchronous version of the command_loop
404 function. The command_loop function will be obsolete when we
405 switch to use the event loop at every execution of gdb. */
407 command_handler (char *command)
409 int stdin_is_tty = ISATTY (stdin);
410 struct cleanup *stat_chain;
413 if (instream == stdin && stdin_is_tty)
414 reinitialize_more_filter ();
416 /* If readline returned a NULL command, it means that the connection
417 with the terminal is gone. This happens at the end of a
418 testsuite run, after Expect has hung up but GDB is still alive.
419 In such a case, we just quit gdb killing the inferior program
423 printf_unfiltered ("quit\n");
424 execute_command ("quit", stdin == instream);
427 stat_chain = make_command_stats_cleanup (1);
429 execute_command (command, instream == stdin);
431 /* Do any commands attached to breakpoint we stopped at. */
432 bpstat_do_actions ();
434 do_cleanups (stat_chain);
437 /* Handle a complete line of input. This is called by the callback
438 mechanism within the readline library. Deal with incomplete
439 commands as well, by saving the partial input in a global
442 /* NOTE: 1999-04-30 This is the asynchronous version of the
443 command_line_input function; command_line_input will become
444 obsolete once we use the event loop as the default mechanism in
447 command_line_handler (char *rl)
449 static char *linebuffer = 0;
450 static unsigned linelength = 0;
456 int repeat = (instream == stdin);
458 if (annotation_level > 1 && instream == stdin)
460 printf_unfiltered (("\n\032\032post-"));
461 puts_unfiltered (async_annotation_suffix);
462 printf_unfiltered (("\n"));
468 linebuffer = (char *) xmalloc (linelength);
475 strcpy (linebuffer, readline_input_state.linebuffer);
476 p = readline_input_state.linebuffer_ptr;
477 xfree (readline_input_state.linebuffer);
483 signal (STOP_SIGNAL, handle_stop_sig);
486 /* Make sure that all output has been output. Some machines may let
487 you get away with leaving out some of the gdb_flush, but not
490 gdb_flush (gdb_stdout);
491 gdb_flush (gdb_stderr);
493 if (source_file_name != NULL)
494 ++source_line_number;
496 /* If we are in this case, then command_handler will call quit
497 and exit from gdb. */
498 if (!rl || rl == (char *) EOF)
504 if (strlen (rl) + 1 + (p - linebuffer) > linelength)
506 linelength = strlen (rl) + 1 + (p - linebuffer);
507 nline = (char *) xrealloc (linebuffer, linelength);
508 p += nline - linebuffer;
512 /* Copy line. Don't copy null at end. (Leaves line alone
513 if this was just a newline). */
517 xfree (rl); /* Allocated in readline. */
519 if (p > linebuffer && *(p - 1) == '\\')
522 p--; /* Put on top of '\'. */
524 readline_input_state.linebuffer = xstrdup (linebuffer);
525 readline_input_state.linebuffer_ptr = p;
527 /* We will not invoke a execute_command if there is more
528 input expected to complete the command. So, we need to
529 print an empty prompt here. */
531 display_gdb_prompt ("");
537 signal (STOP_SIGNAL, SIG_DFL);
540 #define SERVER_COMMAND_LENGTH 7
542 (p - linebuffer > SERVER_COMMAND_LENGTH)
543 && strncmp (linebuffer, "server ", SERVER_COMMAND_LENGTH) == 0;
546 /* Note that we don't set `line'. Between this and the check in
547 dont_repeat, this insures that repeating will still do the
550 command_handler (linebuffer + SERVER_COMMAND_LENGTH);
551 display_gdb_prompt (0);
555 /* Do history expansion if that is wished. */
556 if (history_expansion_p && instream == stdin
557 && ISATTY (instream))
562 *p = '\0'; /* Insert null now. */
563 expanded = history_expand (linebuffer, &history_value);
566 /* Print the changes. */
567 printf_unfiltered ("%s\n", history_value);
569 /* If there was an error, call this function again. */
572 xfree (history_value);
575 if (strlen (history_value) > linelength)
577 linelength = strlen (history_value) + 1;
578 linebuffer = (char *) xrealloc (linebuffer, linelength);
580 strcpy (linebuffer, history_value);
581 p = linebuffer + strlen (linebuffer);
583 xfree (history_value);
586 /* If we just got an empty line, and that is supposed to repeat the
587 previous command, return the value in the global buffer. */
588 if (repeat && p == linebuffer && *p != '\\')
590 command_handler (saved_command_line);
591 display_gdb_prompt (0);
595 for (p1 = linebuffer; *p1 == ' ' || *p1 == '\t'; p1++);
598 command_handler (saved_command_line);
599 display_gdb_prompt (0);
605 /* Add line to history if appropriate. */
606 if (instream == stdin
607 && ISATTY (stdin) && *linebuffer)
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 /* If SIGTRAP was set to SIG_IGN, then the SIG_IGN will get passed
736 to the inferior and breakpoints will be ignored. */
738 signal (SIGTRAP, SIG_DFL);
742 /* If we initialize SIGQUIT to SIG_IGN, then the SIG_IGN will get
743 passed to the inferior, which we don't want. It would be
744 possible to do a "signal (SIGQUIT, SIG_DFL)" after we fork, but
745 on BSD4.3 systems using vfork, that can affect the
746 GDB process as well as the inferior (the signal handling tables
747 might be in memory, shared between the two). Since we establish
748 a handler for SIGQUIT, when we call exec it will set the signal
749 to SIG_DFL for us. */
750 signal (SIGQUIT, handle_sigquit);
752 create_async_signal_handler (async_do_nothing, NULL);
755 if (signal (SIGHUP, handle_sighup) != SIG_IGN)
757 create_async_signal_handler (async_disconnect, NULL);
760 create_async_signal_handler (async_do_nothing, NULL);
762 signal (SIGFPE, handle_sigfpe);
764 create_async_signal_handler (async_float_handler, NULL);
768 create_async_signal_handler (async_stop_sig, NULL);
774 mark_async_signal_handler_wrapper (void *token)
776 mark_async_signal_handler ((struct async_signal_handler *) token);
779 /* Tell the event loop what to do if SIGINT is received.
780 See event-signal.c. */
782 handle_sigint (int sig)
784 signal (sig, handle_sigint);
786 /* We could be running in a loop reading in symfiles or something so
787 it may be quite a while before we get back to the event loop. So
788 set quit_flag to 1 here. Then if QUIT is called before we get to
789 the event loop, we will unwind as expected. */
793 /* If immediate_quit is set, we go ahead and process the SIGINT right
794 away, even if we usually would defer this to the event loop. The
795 assumption here is that it is safe to process ^C immediately if
796 immediate_quit is set. If we didn't, SIGINT would be really
797 processed only the next time through the event loop. To get to
798 that point, though, the command that we want to interrupt needs to
799 finish first, which is unacceptable. If immediate quit is not set,
800 we process SIGINT the next time through the loop, which is fine. */
801 gdb_call_async_signal_handler (sigint_token, immediate_quit);
804 /* Quit GDB if SIGTERM is received.
805 GDB would quit anyway, but this way it will clean up properly. */
807 handle_sigterm (int sig)
809 signal (sig, handle_sigterm);
810 quit_force ((char *) 0, stdin == instream);
813 /* Do the quit. All the checks have been done by the caller. */
815 async_request_quit (gdb_client_data arg)
817 /* If the quit_flag has gotten reset back to 0 by the time we get
818 back here, that means that an exception was thrown to unwind the
819 current command before we got back to the event loop. So there
820 is no reason to call quit again here. */
822 if (check_quit_flag ())
827 /* Tell the event loop what to do if SIGQUIT is received.
828 See event-signal.c. */
830 handle_sigquit (int sig)
832 mark_async_signal_handler_wrapper (sigquit_token);
833 signal (sig, handle_sigquit);
837 #if defined (SIGQUIT) || defined (SIGHUP)
838 /* Called by the event loop in response to a SIGQUIT or an
841 async_do_nothing (gdb_client_data arg)
843 /* Empty function body. */
848 /* Tell the event loop what to do if SIGHUP is received.
849 See event-signal.c. */
851 handle_sighup (int sig)
853 mark_async_signal_handler_wrapper (sighup_token);
854 signal (sig, handle_sighup);
857 /* Called by the event loop to process a SIGHUP. */
859 async_disconnect (gdb_client_data arg)
861 volatile struct gdb_exception exception;
863 TRY_CATCH (exception, RETURN_MASK_ALL)
868 if (exception.reason < 0)
870 fputs_filtered ("Could not kill the program being debugged",
872 exception_print (gdb_stderr, exception);
875 TRY_CATCH (exception, RETURN_MASK_ALL)
880 signal (SIGHUP, SIG_DFL); /*FIXME: ??????????? */
887 handle_stop_sig (int sig)
889 mark_async_signal_handler_wrapper (sigtstp_token);
890 signal (sig, handle_stop_sig);
894 async_stop_sig (gdb_client_data arg)
896 char *prompt = get_prompt ();
898 #if STOP_SIGNAL == SIGTSTP
899 signal (SIGTSTP, SIG_DFL);
905 sigprocmask (SIG_SETMASK, &zero, 0);
907 #elif HAVE_SIGSETMASK
911 signal (SIGTSTP, handle_stop_sig);
913 signal (STOP_SIGNAL, handle_stop_sig);
915 printf_unfiltered ("%s", prompt);
916 gdb_flush (gdb_stdout);
918 /* Forget about any previous command -- null line now will do
922 #endif /* STOP_SIGNAL */
924 /* Tell the event loop what to do if SIGFPE is received.
925 See event-signal.c. */
927 handle_sigfpe (int sig)
929 mark_async_signal_handler_wrapper (sigfpe_token);
930 signal (sig, handle_sigfpe);
933 /* Event loop will call this functin to process a SIGFPE. */
935 async_float_handler (gdb_client_data arg)
937 /* This message is based on ANSI C, section 4.7. Note that integer
938 divide by zero causes this, so "float" is a misnomer. */
939 error (_("Erroneous arithmetic operation."));
943 /* Called by do_setshow_command. */
945 set_async_editing_command (char *args, int from_tty,
946 struct cmd_list_element *c)
948 change_line_handler ();
951 /* Set things up for readline to be invoked via the alternate
952 interface, i.e. via a callback function (rl_callback_read_char),
953 and hook up instream to the event loop. */
955 gdb_setup_readline (void)
957 /* This function is a noop for the sync case. The assumption is
958 that the sync setup is ALL done in gdb_init, and we would only
959 mess it up here. The sync stuff should really go away over
962 gdb_stdout = stdio_fileopen (stdout);
963 gdb_stderr = stdio_fileopen (stderr);
964 gdb_stdlog = gdb_stderr; /* for moment */
965 gdb_stdtarg = gdb_stderr; /* for moment */
966 gdb_stdtargerr = gdb_stderr; /* for moment */
968 /* If the input stream is connected to a terminal, turn on
970 if (ISATTY (instream))
972 /* Tell gdb that we will be using the readline library. This
973 could be overwritten by a command in .gdbinit like 'set
974 editing on' or 'off'. */
975 async_command_editing_p = 1;
977 /* When a character is detected on instream by select or poll,
978 readline will be invoked via this callback function. */
979 call_readline = rl_callback_read_char_wrapper;
983 async_command_editing_p = 0;
984 call_readline = gdb_readline2;
987 /* When readline has read an end-of-line character, it passes the
988 complete line to gdb for processing; command_line_handler is the
989 function that does this. */
990 input_handler = command_line_handler;
992 /* Tell readline to use the same input stream that gdb uses. */
993 rl_instream = instream;
995 /* Get a file descriptor for the input stream, so that we can
996 register it with the event loop. */
997 input_fd = fileno (instream);
999 /* Now we need to create the event sources for the input file
1001 /* At this point in time, this is the only event source that we
1002 register with the even loop. Another source is going to be the
1003 target program (inferior), but that must be registered only when
1004 it actually exists (I.e. after we say 'run' or after we connect
1005 to a remote target. */
1006 add_file_handler (input_fd, stdin_event_handler, 0);
1009 /* Disable command input through the standard CLI channels. Used in
1010 the suspend proc for interpreters that use the standard gdb readline
1011 interface, like the cli & the mi. */
1013 gdb_disable_readline (void)
1015 /* FIXME - It is too heavyweight to delete and remake these every
1016 time you run an interpreter that needs readline. It is probably
1017 better to have the interpreters cache these, which in turn means
1018 that this needs to be moved into interpreter specific code. */
1021 ui_file_delete (gdb_stdout);
1022 ui_file_delete (gdb_stderr);
1025 gdb_stdtargerr = NULL;
1028 rl_callback_handler_remove ();
1029 delete_file_handler (input_fd);