Import gdb 7.3 into vendor branch
[dragonfly.git] / contrib / gdb-7 / gdb / event-top.c
CommitLineData
5796c8dc
SS
1/* Top level stuff for GDB, the GNU debugger.
2
c50c785c
JM
3 Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2007, 2008, 2009, 2010,
4 2011 Free Software Foundation, Inc.
5796c8dc
SS
5
6 Written by Elena Zannoni <ezannoni@cygnus.com> of Cygnus Solutions.
7
8 This file is part of GDB.
9
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.
14
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.
19
20 You should have received a copy of the GNU General Public License
c50c785c 21 along with this program. If not, see <http://www.gnu.org/licenses/>. */
5796c8dc
SS
22
23#include "defs.h"
24#include "top.h"
25#include "inferior.h"
26#include "target.h"
27#include "terminal.h" /* for job_control */
28#include "event-loop.h"
29#include "event-top.h"
30#include "interps.h"
31#include <signal.h>
32#include "exceptions.h"
33#include "cli/cli-script.h" /* for reset_command_nest_depth */
34#include "main.h"
35#include "gdbthread.h"
36
c50c785c 37#include "gdbcmd.h" /* for dont_repeat() */
5796c8dc 38
c50c785c 39/* readline include files. */
5796c8dc
SS
40#include "readline/readline.h"
41#include "readline/history.h"
42
43/* readline defines this. */
44#undef savestring
45
46static void rl_callback_read_char_wrapper (gdb_client_data client_data);
47static void command_line_handler (char *rl);
48static void change_line_handler (void);
49static void change_annotation_level (void);
50static void command_handler (char *command);
51
c50c785c 52/* Signal handlers. */
5796c8dc
SS
53#ifdef SIGQUIT
54static void handle_sigquit (int sig);
55#endif
56#ifdef SIGHUP
57static void handle_sighup (int sig);
58#endif
59static void handle_sigfpe (int sig);
60#if defined(SIGWINCH) && defined(SIGWINCH_HANDLER)
61static void handle_sigwinch (int sig);
62#endif
63
64/* Functions to be invoked by the event loop in response to
c50c785c 65 signals. */
5796c8dc
SS
66#if defined (SIGQUIT) || defined (SIGHUP)
67static void async_do_nothing (gdb_client_data);
68#endif
69#ifdef SIGHUP
70static void async_disconnect (gdb_client_data);
71#endif
72static void async_float_handler (gdb_client_data);
73#ifdef STOP_SIGNAL
74static void async_stop_sig (gdb_client_data);
75#endif
76
77/* Readline offers an alternate interface, via callback
c50c785c 78 functions. These are all included in the file callback.c in the
5796c8dc
SS
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
c50c785c 83 there is a new character ready on the input stream. This function
5796c8dc
SS
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
c50c785c 89 of the old command_line_input in gdb. Instead of invoking (and waiting
5796c8dc
SS
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
c50c785c 95 that readline offers as callback to the event_loop. */
5796c8dc
SS
96
97void (*input_handler) (char *);
98void (*call_readline) (gdb_client_data);
99
c50c785c 100/* Important variables for the event loop. */
5796c8dc
SS
101
102/* This is used to determine if GDB is using the readline library or
c50c785c 103 its own simplified form of readline. It is used by the asynchronous
5796c8dc
SS
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
c50c785c 107 loop as default engine, and event-top.c is merged into top.c. */
5796c8dc
SS
108int async_command_editing_p;
109
110/* This variable contains the new prompt that the user sets with the
c50c785c 111 set prompt command. */
5796c8dc
SS
112char *new_async_prompt;
113
114/* This is the annotation suffix that will be used when the
c50c785c 115 annotation_level is 2. */
5796c8dc
SS
116char *async_annotation_suffix;
117
118/* This is used to display the notification of the completion of an
c50c785c 119 asynchronous execution command. */
5796c8dc
SS
120int exec_done_display_p = 0;
121
122/* This is the file descriptor for the input stream that GDB uses to
c50c785c 123 read commands from. */
5796c8dc
SS
124int input_fd;
125
c50c785c 126/* This is the prompt stack. Prompts will be pushed on the stack as
5796c8dc 127 needed by the different 'kinds' of user inputs GDB is asking
c50c785c 128 for. See event-loop.h. */
5796c8dc
SS
129struct prompts the_prompts;
130
c50c785c 131/* Signal handling variables. */
5796c8dc 132/* Each of these is a pointer to a function that the event loop will
c50c785c 133 invoke if the corresponding signal has received. The real signal
5796c8dc 134 handlers mark these functions as ready to be executed and the event
c50c785c
JM
135 loop, in a later iteration, calls them. See the function
136 invoke_async_signal_handler. */
5796c8dc
SS
137void *sigint_token;
138#ifdef SIGHUP
139void *sighup_token;
140#endif
141#ifdef SIGQUIT
142void *sigquit_token;
143#endif
144void *sigfpe_token;
145#if defined(SIGWINCH) && defined(SIGWINCH_HANDLER)
146void *sigwinch_token;
147#endif
148#ifdef STOP_SIGNAL
149void *sigtstp_token;
150#endif
151
152/* Structure to save a partially entered command. This is used when
c50c785c 153 the user types '\' at the end of a command line. This is necessary
5796c8dc
SS
154 because each line of input is handled by a different call to
155 command_line_handler, and normally there is no state retained
c50c785c 156 between different calls. */
5796c8dc
SS
157int more_to_come = 0;
158
159struct readline_input_state
160 {
161 char *linebuffer;
162 char *linebuffer_ptr;
163 }
164readline_input_state;
165
166/* This hook is called by rl_callback_read_char_wrapper after each
167 character is processed. */
c50c785c 168void (*after_char_processing_hook) (void);
5796c8dc
SS
169\f
170
c50c785c
JM
171/* Wrapper function for calling into the readline library. The event
172 loop expects the callback function to have a paramter, while
173 readline expects none. */
5796c8dc
SS
174static void
175rl_callback_read_char_wrapper (gdb_client_data client_data)
176{
177 rl_callback_read_char ();
178 if (after_char_processing_hook)
179 (*after_char_processing_hook) ();
180}
181
182/* Initialize all the necessary variables, start the event loop,
c50c785c 183 register readline, and stdin, start the loop. */
5796c8dc
SS
184void
185cli_command_loop (void)
186{
187 /* If we are using readline, set things up and display the first
c50c785c 188 prompt, otherwise just print the prompt. */
5796c8dc
SS
189 if (async_command_editing_p)
190 {
191 int length;
192 char *a_prompt;
193 char *gdb_prompt = get_prompt ();
194
c50c785c
JM
195 /* Tell readline what the prompt to display is and what function
196 it will need to call after a whole line is read. This also
197 displays the first prompt. */
5796c8dc
SS
198 length = strlen (PREFIX (0))
199 + strlen (gdb_prompt) + strlen (SUFFIX (0)) + 1;
200 a_prompt = (char *) alloca (length);
201 strcpy (a_prompt, PREFIX (0));
202 strcat (a_prompt, gdb_prompt);
203 strcat (a_prompt, SUFFIX (0));
204 rl_callback_handler_install (a_prompt, input_handler);
205 }
206 else
207 display_gdb_prompt (0);
208
c50c785c 209 /* Now it's time to start the event loop. */
5796c8dc
SS
210 start_event_loop ();
211}
212
213/* Change the function to be invoked every time there is a character
c50c785c 214 ready on stdin. This is used when the user sets the editing off,
5796c8dc 215 therefore bypassing readline, and letting gdb handle the input
c50c785c 216 itself, via gdb_readline2. Also it is used in the opposite case in
5796c8dc 217 which the user sets editing on again, by restoring readline
c50c785c 218 handling of the input. */
5796c8dc
SS
219static void
220change_line_handler (void)
221{
c50c785c
JM
222 /* NOTE: this operates on input_fd, not instream. If we are reading
223 commands from a file, instream will point to the file. However in
5796c8dc 224 async mode, we always read commands from a file with editing
c50c785c
JM
225 off. This means that the 'set editing on/off' will have effect
226 only on the interactive session. */
5796c8dc
SS
227
228 if (async_command_editing_p)
229 {
c50c785c 230 /* Turn on editing by using readline. */
5796c8dc
SS
231 call_readline = rl_callback_read_char_wrapper;
232 input_handler = command_line_handler;
233 }
234 else
235 {
c50c785c 236 /* Turn off editing by using gdb_readline2. */
5796c8dc
SS
237 rl_callback_handler_remove ();
238 call_readline = gdb_readline2;
239
240 /* Set up the command handler as well, in case we are called as
c50c785c 241 first thing from .gdbinit. */
5796c8dc
SS
242 input_handler = command_line_handler;
243 }
244}
245
246/* Displays the prompt. The prompt that is displayed is the current
247 top of the prompt stack, if the argument NEW_PROMPT is
c50c785c 248 0. Otherwise, it displays whatever NEW_PROMPT is. This is used
5796c8dc 249 after each gdb command has completed, and in the following cases:
c50c785c 250 1. When the user enters a command line which is ended by '\'
5796c8dc
SS
251 indicating that the command will continue on the next line.
252 In that case the prompt that is displayed is the empty string.
253 2. When the user is entering 'commands' for a breakpoint, or
c50c785c 254 actions for a tracepoint. In this case the prompt will be '>'
5796c8dc 255 3. Other????
c50c785c 256 FIXME: 2. & 3. not implemented yet for async. */
5796c8dc
SS
257void
258display_gdb_prompt (char *new_prompt)
259{
260 int prompt_length = 0;
261 char *gdb_prompt = get_prompt ();
262
263 /* Reset the nesting depth used when trace-commands is set. */
264 reset_command_nest_depth ();
265
266 /* Each interpreter has its own rules on displaying the command
267 prompt. */
268 if (!current_interp_display_prompt_p ())
269 return;
270
271 if (sync_execution && is_running (inferior_ptid))
272 {
273 /* This is to trick readline into not trying to display the
274 prompt. Even though we display the prompt using this
275 function, readline still tries to do its own display if we
276 don't call rl_callback_handler_install and
277 rl_callback_handler_remove (which readline detects because a
c50c785c 278 global variable is not set). If readline did that, it could
5796c8dc
SS
279 mess up gdb signal handlers for SIGINT. Readline assumes
280 that between calls to rl_set_signals and rl_clear_signals gdb
c50c785c 281 doesn't do anything with the signal handlers. Well, that's
5796c8dc 282 not the case, because when the target executes we change the
c50c785c 283 SIGINT signal handler. If we allowed readline to display the
5796c8dc
SS
284 prompt, the signal handler change would happen exactly
285 between the calls to the above two functions.
c50c785c 286 Calling rl_callback_handler_remove(), does the job. */
5796c8dc
SS
287
288 rl_callback_handler_remove ();
289 return;
290 }
291
292 if (!new_prompt)
293 {
c50c785c 294 /* Just use the top of the prompt stack. */
5796c8dc
SS
295 prompt_length = strlen (PREFIX (0)) +
296 strlen (SUFFIX (0)) +
297 strlen (gdb_prompt) + 1;
298
299 new_prompt = (char *) alloca (prompt_length);
300
c50c785c 301 /* Prefix needs to have new line at end. */
5796c8dc
SS
302 strcpy (new_prompt, PREFIX (0));
303 strcat (new_prompt, gdb_prompt);
304 /* Suffix needs to have a new line at end and \032 \032 at
c50c785c 305 beginning. */
5796c8dc
SS
306 strcat (new_prompt, SUFFIX (0));
307 }
308
309 if (async_command_editing_p)
310 {
311 rl_callback_handler_remove ();
312 rl_callback_handler_install (new_prompt, input_handler);
313 }
c50c785c
JM
314 /* new_prompt at this point can be the top of the stack or the one
315 passed in. It can't be NULL. */
316 else
5796c8dc
SS
317 {
318 /* Don't use a _filtered function here. It causes the assumed
319 character position to be off, since the newline we read from
320 the user is not accounted for. */
321 fputs_unfiltered (new_prompt, gdb_stdout);
322 gdb_flush (gdb_stdout);
323 }
324}
325
326/* Used when the user requests a different annotation level, with
c50c785c 327 'set annotate'. It pushes a new prompt (with prefix and suffix) on top
5796c8dc
SS
328 of the prompt stack, if the annotation level desired is 2, otherwise
329 it pops the top of the prompt stack when we want the annotation level
c50c785c 330 to be the normal ones (1 or 0). */
5796c8dc
SS
331static void
332change_annotation_level (void)
333{
334 char *prefix, *suffix;
335
336 if (!PREFIX (0) || !PROMPT (0) || !SUFFIX (0))
337 {
338 /* The prompt stack has not been initialized to "", we are
c50c785c 339 using gdb w/o the --async switch. */
5796c8dc
SS
340 warning (_("Command has same effect as set annotate"));
341 return;
342 }
343
344 if (annotation_level > 1)
345 {
346 if (!strcmp (PREFIX (0), "") && !strcmp (SUFFIX (0), ""))
347 {
c50c785c 348 /* Push a new prompt if the previous annotation_level was not >1. */
5796c8dc
SS
349 prefix = (char *) alloca (strlen (async_annotation_suffix) + 10);
350 strcpy (prefix, "\n\032\032pre-");
351 strcat (prefix, async_annotation_suffix);
352 strcat (prefix, "\n");
353
354 suffix = (char *) alloca (strlen (async_annotation_suffix) + 6);
355 strcpy (suffix, "\n\032\032");
356 strcat (suffix, async_annotation_suffix);
357 strcat (suffix, "\n");
358
359 push_prompt (prefix, (char *) 0, suffix);
360 }
361 }
362 else
363 {
364 if (strcmp (PREFIX (0), "") && strcmp (SUFFIX (0), ""))
365 {
c50c785c 366 /* Pop the top of the stack, we are going back to annotation < 1. */
5796c8dc
SS
367 pop_prompt ();
368 }
369 }
370}
371
c50c785c
JM
372/* Pushes a new prompt on the prompt stack. Each prompt has three
373 parts: prefix, prompt, suffix. Usually prefix and suffix are empty
374 strings, except when the annotation level is 2. Memory is allocated
375 within xstrdup for the new prompt. */
5796c8dc
SS
376void
377push_prompt (char *prefix, char *prompt, char *suffix)
378{
379 the_prompts.top++;
380 PREFIX (0) = xstrdup (prefix);
381
382 /* Note that this function is used by the set annotate 2
c50c785c
JM
383 command. This is why we take care of saving the old prompt
384 in case a new one is not specified. */
5796c8dc
SS
385 if (prompt)
386 PROMPT (0) = xstrdup (prompt);
387 else
388 PROMPT (0) = xstrdup (PROMPT (-1));
389
390 SUFFIX (0) = xstrdup (suffix);
391}
392
c50c785c
JM
393/* Pops the top of the prompt stack, and frees the memory allocated
394 for it. */
5796c8dc
SS
395void
396pop_prompt (void)
397{
398 /* If we are not during a 'synchronous' execution command, in which
c50c785c 399 case, the top prompt would be empty. */
5796c8dc
SS
400 if (strcmp (PROMPT (0), ""))
401 /* This is for the case in which the prompt is set while the
c50c785c 402 annotation level is 2. The top prompt will be changed, but when
5796c8dc 403 we return to annotation level < 2, we want that new prompt to be
c50c785c 404 in effect, until the user does another 'set prompt'. */
5796c8dc
SS
405 if (strcmp (PROMPT (0), PROMPT (-1)))
406 {
407 xfree (PROMPT (-1));
408 PROMPT (-1) = xstrdup (PROMPT (0));
409 }
410
411 xfree (PREFIX (0));
412 xfree (PROMPT (0));
413 xfree (SUFFIX (0));
414 the_prompts.top--;
415}
416
417/* When there is an event ready on the stdin file desriptor, instead
418 of calling readline directly throught the callback function, or
419 instead of calling gdb_readline2, give gdb a chance to detect
c50c785c 420 errors and do something. */
5796c8dc
SS
421void
422stdin_event_handler (int error, gdb_client_data client_data)
423{
424 if (error)
425 {
426 printf_unfiltered (_("error detected on stdin\n"));
427 delete_file_handler (input_fd);
428 discard_all_continuations ();
429 discard_all_intermediate_continuations ();
c50c785c 430 /* If stdin died, we may as well kill gdb. */
5796c8dc
SS
431 quit_command ((char *) 0, stdin == instream);
432 }
433 else
434 (*call_readline) (client_data);
435}
436
437/* Re-enable stdin after the end of an execution command in
438 synchronous mode, or after an error from the target, and we aborted
c50c785c 439 the exec operation. */
5796c8dc
SS
440
441void
442async_enable_stdin (void)
443{
444 if (sync_execution)
445 {
c50c785c 446 /* See NOTE in async_disable_stdin(). */
5796c8dc
SS
447 /* FIXME: cagney/1999-09-27: Call this before clearing
448 sync_execution. Current target_terminal_ours() implementations
c50c785c 449 check for sync_execution before switching the terminal. */
5796c8dc
SS
450 target_terminal_ours ();
451 pop_prompt ();
452 sync_execution = 0;
453 }
454}
455
456/* Disable reads from stdin (the console) marking the command as
c50c785c 457 synchronous. */
5796c8dc
SS
458
459void
460async_disable_stdin (void)
461{
462 if (!sync_execution)
463 {
464 sync_execution = 1;
465 push_prompt ("", "", "");
466 }
467}
468\f
469
c50c785c 470/* Handles a gdb command. This function is called by
5796c8dc 471 command_line_handler, which has processed one or more input lines
c50c785c 472 into COMMAND. */
5796c8dc
SS
473/* NOTE: 1999-04-30 This is the asynchronous version of the command_loop
474 function. The command_loop function will be obsolete when we
c50c785c 475 switch to use the event loop at every execution of gdb. */
5796c8dc
SS
476static void
477command_handler (char *command)
478{
479 int stdin_is_tty = ISATTY (stdin);
cf7f2e2d 480 struct cleanup *stat_chain;
5796c8dc
SS
481
482 quit_flag = 0;
483 if (instream == stdin && stdin_is_tty)
484 reinitialize_more_filter ();
485
c50c785c
JM
486 /* If readline returned a NULL command, it means that the connection
487 with the terminal is gone. This happens at the end of a
488 testsuite run, after Expect has hung up but GDB is still alive.
489 In such a case, we just quit gdb killing the inferior program
490 too. */
5796c8dc
SS
491 if (command == 0)
492 {
493 printf_unfiltered ("quit\n");
494 execute_command ("quit", stdin == instream);
495 }
496
cf7f2e2d 497 stat_chain = make_command_stats_cleanup (1);
5796c8dc
SS
498
499 execute_command (command, instream == stdin);
500
501 /* Do any commands attached to breakpoint we stopped at. */
502 bpstat_do_actions ();
503
cf7f2e2d 504 do_cleanups (stat_chain);
5796c8dc
SS
505}
506
c50c785c
JM
507/* Handle a complete line of input. This is called by the callback
508 mechanism within the readline library. Deal with incomplete
509 commands as well, by saving the partial input in a global
510 buffer. */
5796c8dc
SS
511
512/* NOTE: 1999-04-30 This is the asynchronous version of the
c50c785c 513 command_line_input function; command_line_input will become
5796c8dc 514 obsolete once we use the event loop as the default mechanism in
c50c785c 515 GDB. */
5796c8dc
SS
516static void
517command_line_handler (char *rl)
518{
519 static char *linebuffer = 0;
520 static unsigned linelength = 0;
521 char *p;
522 char *p1;
523 extern char *line;
524 extern int linesize;
525 char *nline;
526 char got_eof = 0;
527
5796c8dc
SS
528 int repeat = (instream == stdin);
529
530 if (annotation_level > 1 && instream == stdin)
531 {
532 printf_unfiltered (("\n\032\032post-"));
533 puts_unfiltered (async_annotation_suffix);
534 printf_unfiltered (("\n"));
535 }
536
537 if (linebuffer == 0)
538 {
539 linelength = 80;
540 linebuffer = (char *) xmalloc (linelength);
541 }
542
543 p = linebuffer;
544
545 if (more_to_come)
546 {
547 strcpy (linebuffer, readline_input_state.linebuffer);
548 p = readline_input_state.linebuffer_ptr;
549 xfree (readline_input_state.linebuffer);
550 more_to_come = 0;
551 pop_prompt ();
552 }
553
554#ifdef STOP_SIGNAL
555 if (job_control)
556 signal (STOP_SIGNAL, handle_stop_sig);
557#endif
558
559 /* Make sure that all output has been output. Some machines may let
c50c785c
JM
560 you get away with leaving out some of the gdb_flush, but not
561 all. */
5796c8dc
SS
562 wrap_here ("");
563 gdb_flush (gdb_stdout);
564 gdb_flush (gdb_stderr);
565
566 if (source_file_name != NULL)
567 ++source_line_number;
568
569 /* If we are in this case, then command_handler will call quit
c50c785c 570 and exit from gdb. */
5796c8dc
SS
571 if (!rl || rl == (char *) EOF)
572 {
573 got_eof = 1;
574 command_handler (0);
c50c785c 575 return; /* Lint. */
5796c8dc
SS
576 }
577 if (strlen (rl) + 1 + (p - linebuffer) > linelength)
578 {
579 linelength = strlen (rl) + 1 + (p - linebuffer);
580 nline = (char *) xrealloc (linebuffer, linelength);
581 p += nline - linebuffer;
582 linebuffer = nline;
583 }
584 p1 = rl;
585 /* Copy line. Don't copy null at end. (Leaves line alone
c50c785c 586 if this was just a newline). */
5796c8dc
SS
587 while (*p1)
588 *p++ = *p1++;
589
590 xfree (rl); /* Allocated in readline. */
591
592 if (p > linebuffer && *(p - 1) == '\\')
593 {
594 *p = '\0';
595 p--; /* Put on top of '\'. */
596
597 readline_input_state.linebuffer = xstrdup (linebuffer);
598 readline_input_state.linebuffer_ptr = p;
599
600 /* We will not invoke a execute_command if there is more
c50c785c
JM
601 input expected to complete the command. So, we need to
602 print an empty prompt here. */
5796c8dc
SS
603 more_to_come = 1;
604 push_prompt ("", "", "");
605 display_gdb_prompt (0);
606 return;
607 }
608
609#ifdef STOP_SIGNAL
610 if (job_control)
611 signal (STOP_SIGNAL, SIG_DFL);
612#endif
613
614#define SERVER_COMMAND_LENGTH 7
615 server_command =
616 (p - linebuffer > SERVER_COMMAND_LENGTH)
617 && strncmp (linebuffer, "server ", SERVER_COMMAND_LENGTH) == 0;
618 if (server_command)
619 {
620 /* Note that we don't set `line'. Between this and the check in
621 dont_repeat, this insures that repeating will still do the
622 right thing. */
623 *p = '\0';
624 command_handler (linebuffer + SERVER_COMMAND_LENGTH);
625 display_gdb_prompt (0);
626 return;
627 }
628
629 /* Do history expansion if that is wished. */
630 if (history_expansion_p && instream == stdin
631 && ISATTY (instream))
632 {
633 char *history_value;
634 int expanded;
635
636 *p = '\0'; /* Insert null now. */
637 expanded = history_expand (linebuffer, &history_value);
638 if (expanded)
639 {
640 /* Print the changes. */
641 printf_unfiltered ("%s\n", history_value);
642
643 /* If there was an error, call this function again. */
644 if (expanded < 0)
645 {
646 xfree (history_value);
647 return;
648 }
649 if (strlen (history_value) > linelength)
650 {
651 linelength = strlen (history_value) + 1;
652 linebuffer = (char *) xrealloc (linebuffer, linelength);
653 }
654 strcpy (linebuffer, history_value);
655 p = linebuffer + strlen (linebuffer);
656 }
657 xfree (history_value);
658 }
659
c50c785c
JM
660 /* If we just got an empty line, and that is supposed to repeat the
661 previous command, return the value in the global buffer. */
5796c8dc
SS
662 if (repeat && p == linebuffer && *p != '\\')
663 {
664 command_handler (line);
665 display_gdb_prompt (0);
666 return;
667 }
668
669 for (p1 = linebuffer; *p1 == ' ' || *p1 == '\t'; p1++);
670 if (repeat && !*p1)
671 {
672 command_handler (line);
673 display_gdb_prompt (0);
674 return;
675 }
676
677 *p = 0;
678
679 /* Add line to history if appropriate. */
680 if (instream == stdin
681 && ISATTY (stdin) && *linebuffer)
682 add_history (linebuffer);
683
684 /* Note: lines consisting solely of comments are added to the command
685 history. This is useful when you type a command, and then
686 realize you don't want to execute it quite yet. You can comment
687 out the command and then later fetch it from the value history
688 and remove the '#'. The kill ring is probably better, but some
689 people are in the habit of commenting things out. */
690 if (*p1 == '#')
c50c785c 691 *p1 = '\0'; /* Found a comment. */
5796c8dc
SS
692
693 /* Save into global buffer if appropriate. */
694 if (repeat)
695 {
696 if (linelength > linesize)
697 {
698 line = xrealloc (line, linelength);
699 linesize = linelength;
700 }
701 strcpy (line, linebuffer);
702 if (!more_to_come)
703 {
704 command_handler (line);
705 display_gdb_prompt (0);
706 }
707 return;
708 }
709
710 command_handler (linebuffer);
711 display_gdb_prompt (0);
712 return;
713}
714
715/* Does reading of input from terminal w/o the editing features
c50c785c 716 provided by the readline library. */
5796c8dc 717
c50c785c 718/* NOTE: 1999-04-30 Asynchronous version of gdb_readline; gdb_readline
5796c8dc 719 will become obsolete when the event loop is made the default
c50c785c 720 execution for gdb. */
5796c8dc
SS
721void
722gdb_readline2 (gdb_client_data client_data)
723{
724 int c;
725 char *result;
726 int input_index = 0;
727 int result_size = 80;
728 static int done_once = 0;
729
730 /* Unbuffer the input stream, so that, later on, the calls to fgetc
c50c785c 731 fetch only one char at the time from the stream. The fgetc's will
5796c8dc 732 get up to the first newline, but there may be more chars in the
c50c785c 733 stream after '\n'. If we buffer the input and fgetc drains the
5796c8dc 734 stream, getting stuff beyond the newline as well, a select, done
c50c785c 735 afterwards will not trigger. */
5796c8dc
SS
736 if (!done_once && !ISATTY (instream))
737 {
738 setbuf (instream, NULL);
739 done_once = 1;
740 }
741
742 result = (char *) xmalloc (result_size);
743
744 /* We still need the while loop here, even though it would seem
745 obvious to invoke gdb_readline2 at every character entered. If
746 not using the readline library, the terminal is in cooked mode,
c50c785c
JM
747 which sends the characters all at once. Poll will notice that the
748 input fd has changed state only after enter is pressed. At this
749 point we still need to fetch all the chars entered. */
5796c8dc
SS
750
751 while (1)
752 {
753 /* Read from stdin if we are executing a user defined command.
754 This is the right thing for prompt_for_continue, at least. */
755 c = fgetc (instream ? instream : stdin);
756
757 if (c == EOF)
758 {
759 if (input_index > 0)
c50c785c
JM
760 /* The last line does not end with a newline. Return it,
761 and if we are called again fgetc will still return EOF
762 and we'll return NULL then. */
5796c8dc
SS
763 break;
764 xfree (result);
765 (*input_handler) (0);
766 return;
767 }
768
769 if (c == '\n')
770 {
771 if (input_index > 0 && result[input_index - 1] == '\r')
772 input_index--;
773 break;
774 }
775
776 result[input_index++] = c;
777 while (input_index >= result_size)
778 {
779 result_size *= 2;
780 result = (char *) xrealloc (result, result_size);
781 }
782 }
783
784 result[input_index++] = '\0';
785 (*input_handler) (result);
786}
787\f
788
789/* Initialization of signal handlers and tokens. There is a function
c50c785c 790 handle_sig* for each of the signals GDB cares about. Specifically:
5796c8dc
SS
791 SIGINT, SIGFPE, SIGQUIT, SIGTSTP, SIGHUP, SIGWINCH. These
792 functions are the actual signal handlers associated to the signals
793 via calls to signal(). The only job for these functions is to
794 enqueue the appropriate event/procedure with the event loop. Such
c50c785c 795 procedures are the old signal handlers. The event loop will take
5796c8dc 796 care of invoking the queued procedures to perform the usual tasks
c50c785c 797 associated with the reception of the signal. */
5796c8dc
SS
798/* NOTE: 1999-04-30 This is the asynchronous version of init_signals.
799 init_signals will become obsolete as we move to have to event loop
c50c785c 800 as the default for gdb. */
5796c8dc
SS
801void
802async_init_signals (void)
803{
804 signal (SIGINT, handle_sigint);
805 sigint_token =
806 create_async_signal_handler (async_request_quit, NULL);
807 signal (SIGTERM, handle_sigterm);
808
809 /* If SIGTRAP was set to SIG_IGN, then the SIG_IGN will get passed
810 to the inferior and breakpoints will be ignored. */
811#ifdef SIGTRAP
812 signal (SIGTRAP, SIG_DFL);
813#endif
814
815#ifdef SIGQUIT
816 /* If we initialize SIGQUIT to SIG_IGN, then the SIG_IGN will get
817 passed to the inferior, which we don't want. It would be
818 possible to do a "signal (SIGQUIT, SIG_DFL)" after we fork, but
819 on BSD4.3 systems using vfork, that can affect the
820 GDB process as well as the inferior (the signal handling tables
821 might be in memory, shared between the two). Since we establish
822 a handler for SIGQUIT, when we call exec it will set the signal
823 to SIG_DFL for us. */
824 signal (SIGQUIT, handle_sigquit);
825 sigquit_token =
826 create_async_signal_handler (async_do_nothing, NULL);
827#endif
828#ifdef SIGHUP
829 if (signal (SIGHUP, handle_sighup) != SIG_IGN)
830 sighup_token =
831 create_async_signal_handler (async_disconnect, NULL);
832 else
833 sighup_token =
834 create_async_signal_handler (async_do_nothing, NULL);
835#endif
836 signal (SIGFPE, handle_sigfpe);
837 sigfpe_token =
838 create_async_signal_handler (async_float_handler, NULL);
839
840#if defined(SIGWINCH) && defined(SIGWINCH_HANDLER)
841 signal (SIGWINCH, handle_sigwinch);
842 sigwinch_token =
843 create_async_signal_handler (SIGWINCH_HANDLER, NULL);
844#endif
845#ifdef STOP_SIGNAL
846 sigtstp_token =
847 create_async_signal_handler (async_stop_sig, NULL);
848#endif
849
850}
851
852void
853mark_async_signal_handler_wrapper (void *token)
854{
855 mark_async_signal_handler ((struct async_signal_handler *) token);
856}
857
c50c785c
JM
858/* Tell the event loop what to do if SIGINT is received.
859 See event-signal.c. */
5796c8dc
SS
860void
861handle_sigint (int sig)
862{
863 signal (sig, handle_sigint);
864
865 /* We could be running in a loop reading in symfiles or something so
866 it may be quite a while before we get back to the event loop. So
c50c785c 867 set quit_flag to 1 here. Then if QUIT is called before we get to
5796c8dc
SS
868 the event loop, we will unwind as expected. */
869
870 quit_flag = 1;
871
872 /* If immediate_quit is set, we go ahead and process the SIGINT right
c50c785c 873 away, even if we usually would defer this to the event loop. The
5796c8dc 874 assumption here is that it is safe to process ^C immediately if
c50c785c 875 immediate_quit is set. If we didn't, SIGINT would be really
5796c8dc
SS
876 processed only the next time through the event loop. To get to
877 that point, though, the command that we want to interrupt needs to
878 finish first, which is unacceptable. If immediate quit is not set,
c50c785c 879 we process SIGINT the next time through the loop, which is fine. */
5796c8dc
SS
880 gdb_call_async_signal_handler (sigint_token, immediate_quit);
881}
882
883/* Quit GDB if SIGTERM is received.
884 GDB would quit anyway, but this way it will clean up properly. */
885void
886handle_sigterm (int sig)
887{
888 signal (sig, handle_sigterm);
889 quit_force ((char *) 0, stdin == instream);
890}
891
c50c785c 892/* Do the quit. All the checks have been done by the caller. */
5796c8dc
SS
893void
894async_request_quit (gdb_client_data arg)
895{
896 /* If the quit_flag has gotten reset back to 0 by the time we get
897 back here, that means that an exception was thrown to unwind the
898 current command before we got back to the event loop. So there
899 is no reason to call quit again here, unless immediate_quit is
c50c785c 900 set. */
5796c8dc
SS
901
902 if (quit_flag || immediate_quit)
903 quit ();
904}
905
906#ifdef SIGQUIT
c50c785c
JM
907/* Tell the event loop what to do if SIGQUIT is received.
908 See event-signal.c. */
5796c8dc
SS
909static void
910handle_sigquit (int sig)
911{
912 mark_async_signal_handler_wrapper (sigquit_token);
913 signal (sig, handle_sigquit);
914}
915#endif
916
917#if defined (SIGQUIT) || defined (SIGHUP)
918/* Called by the event loop in response to a SIGQUIT or an
919 ignored SIGHUP. */
920static void
921async_do_nothing (gdb_client_data arg)
922{
c50c785c 923 /* Empty function body. */
5796c8dc
SS
924}
925#endif
926
927#ifdef SIGHUP
c50c785c
JM
928/* Tell the event loop what to do if SIGHUP is received.
929 See event-signal.c. */
5796c8dc
SS
930static void
931handle_sighup (int sig)
932{
933 mark_async_signal_handler_wrapper (sighup_token);
934 signal (sig, handle_sighup);
935}
936
c50c785c 937/* Called by the event loop to process a SIGHUP. */
5796c8dc
SS
938static void
939async_disconnect (gdb_client_data arg)
940{
941 catch_errors (quit_cover, NULL,
942 "Could not kill the program being debugged",
943 RETURN_MASK_ALL);
c50c785c 944 signal (SIGHUP, SIG_DFL); /*FIXME: ??????????? */
5796c8dc
SS
945 raise (SIGHUP);
946}
947#endif
948
949#ifdef STOP_SIGNAL
950void
951handle_stop_sig (int sig)
952{
953 mark_async_signal_handler_wrapper (sigtstp_token);
954 signal (sig, handle_stop_sig);
955}
956
957static void
958async_stop_sig (gdb_client_data arg)
959{
960 char *prompt = get_prompt ();
cf7f2e2d 961
5796c8dc
SS
962#if STOP_SIGNAL == SIGTSTP
963 signal (SIGTSTP, SIG_DFL);
964#if HAVE_SIGPROCMASK
965 {
966 sigset_t zero;
967
968 sigemptyset (&zero);
969 sigprocmask (SIG_SETMASK, &zero, 0);
970 }
971#elif HAVE_SIGSETMASK
972 sigsetmask (0);
973#endif
974 raise (SIGTSTP);
975 signal (SIGTSTP, handle_stop_sig);
976#else
977 signal (STOP_SIGNAL, handle_stop_sig);
978#endif
979 printf_unfiltered ("%s", prompt);
980 gdb_flush (gdb_stdout);
981
c50c785c
JM
982 /* Forget about any previous command -- null line now will do
983 nothing. */
5796c8dc
SS
984 dont_repeat ();
985}
986#endif /* STOP_SIGNAL */
987
c50c785c
JM
988/* Tell the event loop what to do if SIGFPE is received.
989 See event-signal.c. */
5796c8dc
SS
990static void
991handle_sigfpe (int sig)
992{
993 mark_async_signal_handler_wrapper (sigfpe_token);
994 signal (sig, handle_sigfpe);
995}
996
c50c785c 997/* Event loop will call this functin to process a SIGFPE. */
5796c8dc
SS
998static void
999async_float_handler (gdb_client_data arg)
1000{
c50c785c
JM
1001 /* This message is based on ANSI C, section 4.7. Note that integer
1002 divide by zero causes this, so "float" is a misnomer. */
5796c8dc
SS
1003 error (_("Erroneous arithmetic operation."));
1004}
1005
c50c785c
JM
1006/* Tell the event loop what to do if SIGWINCH is received.
1007 See event-signal.c. */
5796c8dc
SS
1008#if defined(SIGWINCH) && defined(SIGWINCH_HANDLER)
1009static void
1010handle_sigwinch (int sig)
1011{
1012 mark_async_signal_handler_wrapper (sigwinch_token);
1013 signal (sig, handle_sigwinch);
1014}
1015#endif
1016\f
1017
1018/* Called by do_setshow_command. */
1019void
c50c785c
JM
1020set_async_editing_command (char *args, int from_tty,
1021 struct cmd_list_element *c)
5796c8dc
SS
1022{
1023 change_line_handler ();
1024}
1025
1026/* Called by do_setshow_command. */
1027void
c50c785c
JM
1028set_async_annotation_level (char *args, int from_tty,
1029 struct cmd_list_element *c)
5796c8dc
SS
1030{
1031 change_annotation_level ();
1032}
1033
1034/* Called by do_setshow_command. */
1035void
1036set_async_prompt (char *args, int from_tty, struct cmd_list_element *c)
1037{
1038 PROMPT (0) = xstrdup (new_async_prompt);
1039}
1040
1041/* Set things up for readline to be invoked via the alternate
1042 interface, i.e. via a callback function (rl_callback_read_char),
c50c785c 1043 and hook up instream to the event loop. */
5796c8dc
SS
1044void
1045gdb_setup_readline (void)
1046{
1047 /* This function is a noop for the sync case. The assumption is
1048 that the sync setup is ALL done in gdb_init, and we would only
1049 mess it up here. The sync stuff should really go away over
1050 time. */
1051 if (!batch_silent)
1052 gdb_stdout = stdio_fileopen (stdout);
1053 gdb_stderr = stdio_fileopen (stderr);
1054 gdb_stdlog = gdb_stderr; /* for moment */
1055 gdb_stdtarg = gdb_stderr; /* for moment */
c50c785c 1056 gdb_stdtargerr = gdb_stderr; /* for moment */
5796c8dc
SS
1057
1058 /* If the input stream is connected to a terminal, turn on
1059 editing. */
1060 if (ISATTY (instream))
1061 {
c50c785c 1062 /* Tell gdb that we will be using the readline library. This
5796c8dc
SS
1063 could be overwritten by a command in .gdbinit like 'set
1064 editing on' or 'off'. */
1065 async_command_editing_p = 1;
1066
1067 /* When a character is detected on instream by select or poll,
1068 readline will be invoked via this callback function. */
1069 call_readline = rl_callback_read_char_wrapper;
1070 }
1071 else
1072 {
1073 async_command_editing_p = 0;
1074 call_readline = gdb_readline2;
1075 }
1076
1077 /* When readline has read an end-of-line character, it passes the
c50c785c 1078 complete line to gdb for processing; command_line_handler is the
5796c8dc
SS
1079 function that does this. */
1080 input_handler = command_line_handler;
1081
c50c785c 1082 /* Tell readline to use the same input stream that gdb uses. */
5796c8dc
SS
1083 rl_instream = instream;
1084
1085 /* Get a file descriptor for the input stream, so that we can
1086 register it with the event loop. */
1087 input_fd = fileno (instream);
1088
1089 /* Now we need to create the event sources for the input file
1090 descriptor. */
1091 /* At this point in time, this is the only event source that we
c50c785c 1092 register with the even loop. Another source is going to be the
5796c8dc
SS
1093 target program (inferior), but that must be registered only when
1094 it actually exists (I.e. after we say 'run' or after we connect
1095 to a remote target. */
1096 add_file_handler (input_fd, stdin_event_handler, 0);
1097}
1098
1099/* Disable command input through the standard CLI channels. Used in
1100 the suspend proc for interpreters that use the standard gdb readline
1101 interface, like the cli & the mi. */
1102void
1103gdb_disable_readline (void)
1104{
1105 /* FIXME - It is too heavyweight to delete and remake these every
1106 time you run an interpreter that needs readline. It is probably
1107 better to have the interpreters cache these, which in turn means
1108 that this needs to be moved into interpreter specific code. */
1109
1110#if 0
1111 ui_file_delete (gdb_stdout);
1112 ui_file_delete (gdb_stderr);
1113 gdb_stdlog = NULL;
1114 gdb_stdtarg = NULL;
c50c785c 1115 gdb_stdtargerr = NULL;
5796c8dc
SS
1116#endif
1117
1118 rl_callback_handler_remove ();
1119 delete_file_handler (input_fd);
1120}