Commit | Line | Data |
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60250e8b AC |
1 | /* Exception (throw catch) mechanism, for GDB, the GNU debugger. |
2 | ||
6aba47ca DJ |
3 | Copyright (C) 1986, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, |
4 | 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 | |
7b871fab | 5 | Free Software Foundation, Inc. |
60250e8b AC |
6 | |
7 | This file is part of GDB. | |
8 | ||
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 | |
a9762ec7 | 11 | the Free Software Foundation; either version 3 of the License, or |
60250e8b AC |
12 | (at your option) any later version. |
13 | ||
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. | |
18 | ||
19 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 20 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
60250e8b AC |
21 | |
22 | #include "defs.h" | |
23 | #include "exceptions.h" | |
60250e8b AC |
24 | #include "breakpoint.h" |
25 | #include "target.h" | |
26 | #include "inferior.h" | |
27 | #include "annotate.h" | |
28 | #include "ui-out.h" | |
29 | #include "gdb_assert.h" | |
db5f402d | 30 | #include "gdb_string.h" |
e06e2353 | 31 | #include "serial.h" |
60250e8b | 32 | |
7b871fab | 33 | const struct gdb_exception exception_none = { 0, GDB_NO_ERROR, NULL }; |
c1043fc2 | 34 | |
db5f402d AC |
35 | /* Possible catcher states. */ |
36 | enum catcher_state { | |
37 | /* Initial state, a new catcher has just been created. */ | |
38 | CATCHER_CREATED, | |
39 | /* The catch code is running. */ | |
40 | CATCHER_RUNNING, | |
41 | CATCHER_RUNNING_1, | |
42 | /* The catch code threw an exception. */ | |
43 | CATCHER_ABORTING | |
44 | }; | |
45 | ||
46 | /* Possible catcher actions. */ | |
47 | enum catcher_action { | |
48 | CATCH_ITER, | |
49 | CATCH_ITER_1, | |
50 | CATCH_THROWING | |
51 | }; | |
52 | ||
53 | struct catcher | |
54 | { | |
55 | enum catcher_state state; | |
2a78bfb5 | 56 | /* Jump buffer pointing back at the exception handler. */ |
6941d02a | 57 | EXCEPTIONS_SIGJMP_BUF buf; |
8a076db9 | 58 | /* Status buffer belonging to the exception handler. */ |
71fff37b | 59 | volatile struct gdb_exception *exception; |
db5f402d AC |
60 | /* Saved/current state. */ |
61 | int mask; | |
db5f402d AC |
62 | struct ui_out *saved_uiout; |
63 | struct cleanup *saved_cleanup_chain; | |
db5f402d AC |
64 | /* Back link. */ |
65 | struct catcher *prev; | |
66 | }; | |
67 | ||
60250e8b | 68 | /* Where to go for throw_exception(). */ |
db5f402d AC |
69 | static struct catcher *current_catcher; |
70 | ||
6941d02a AC |
71 | EXCEPTIONS_SIGJMP_BUF * |
72 | exceptions_state_mc_init (struct ui_out *func_uiout, | |
71fff37b | 73 | volatile struct gdb_exception *exception, |
6941d02a | 74 | return_mask mask) |
db5f402d AC |
75 | { |
76 | struct catcher *new_catcher = XZALLOC (struct catcher); | |
77 | ||
2a78bfb5 AC |
78 | /* Start with no exception, save it's address. */ |
79 | exception->reason = 0; | |
7b871fab | 80 | exception->error = GDB_NO_ERROR; |
2a78bfb5 AC |
81 | exception->message = NULL; |
82 | new_catcher->exception = exception; | |
83 | ||
db5f402d AC |
84 | new_catcher->mask = mask; |
85 | ||
db5f402d AC |
86 | /* Override the global ``struct ui_out'' builder. */ |
87 | new_catcher->saved_uiout = uiout; | |
88 | uiout = func_uiout; | |
89 | ||
90 | /* Prevent error/quit during FUNC from calling cleanups established | |
91 | prior to here. */ | |
92 | new_catcher->saved_cleanup_chain = save_cleanups (); | |
93 | ||
94 | /* Push this new catcher on the top. */ | |
95 | new_catcher->prev = current_catcher; | |
96 | current_catcher = new_catcher; | |
97 | new_catcher->state = CATCHER_CREATED; | |
98 | ||
99 | return &new_catcher->buf; | |
100 | } | |
101 | ||
102 | static void | |
103 | catcher_pop (void) | |
104 | { | |
105 | struct catcher *old_catcher = current_catcher; | |
106 | current_catcher = old_catcher->prev; | |
107 | ||
108 | /* Restore the cleanup chain, the error/quit messages, and the uiout | |
109 | builder, to their original states. */ | |
110 | ||
111 | restore_cleanups (old_catcher->saved_cleanup_chain); | |
112 | ||
113 | uiout = old_catcher->saved_uiout; | |
114 | ||
db5f402d AC |
115 | xfree (old_catcher); |
116 | } | |
117 | ||
118 | /* Catcher state machine. Returns non-zero if the m/c should be run | |
119 | again, zero if it should abort. */ | |
120 | ||
6941d02a AC |
121 | static int |
122 | exceptions_state_mc (enum catcher_action action) | |
db5f402d AC |
123 | { |
124 | switch (current_catcher->state) | |
125 | { | |
126 | case CATCHER_CREATED: | |
127 | switch (action) | |
128 | { | |
129 | case CATCH_ITER: | |
130 | /* Allow the code to run the catcher. */ | |
131 | current_catcher->state = CATCHER_RUNNING; | |
132 | return 1; | |
133 | default: | |
e2e0b3e5 | 134 | internal_error (__FILE__, __LINE__, _("bad state")); |
db5f402d AC |
135 | } |
136 | case CATCHER_RUNNING: | |
137 | switch (action) | |
138 | { | |
139 | case CATCH_ITER: | |
140 | /* No error/quit has occured. Just clean up. */ | |
141 | catcher_pop (); | |
142 | return 0; | |
143 | case CATCH_ITER_1: | |
144 | current_catcher->state = CATCHER_RUNNING_1; | |
145 | return 1; | |
146 | case CATCH_THROWING: | |
147 | current_catcher->state = CATCHER_ABORTING; | |
148 | /* See also throw_exception. */ | |
149 | return 1; | |
150 | default: | |
e2e0b3e5 | 151 | internal_error (__FILE__, __LINE__, _("bad switch")); |
db5f402d AC |
152 | } |
153 | case CATCHER_RUNNING_1: | |
154 | switch (action) | |
155 | { | |
156 | case CATCH_ITER: | |
157 | /* The did a "break" from the inner while loop. */ | |
158 | catcher_pop (); | |
159 | return 0; | |
160 | case CATCH_ITER_1: | |
161 | current_catcher->state = CATCHER_RUNNING; | |
162 | return 0; | |
163 | case CATCH_THROWING: | |
164 | current_catcher->state = CATCHER_ABORTING; | |
165 | /* See also throw_exception. */ | |
166 | return 1; | |
167 | default: | |
e2e0b3e5 | 168 | internal_error (__FILE__, __LINE__, _("bad switch")); |
db5f402d AC |
169 | } |
170 | case CATCHER_ABORTING: | |
171 | switch (action) | |
172 | { | |
173 | case CATCH_ITER: | |
174 | { | |
71fff37b | 175 | struct gdb_exception exception = *current_catcher->exception; |
2a78bfb5 | 176 | if (current_catcher->mask & RETURN_MASK (exception.reason)) |
db5f402d AC |
177 | { |
178 | /* Exit normally if this catcher can handle this | |
179 | exception. The caller analyses the func return | |
180 | values. */ | |
181 | catcher_pop (); | |
182 | return 0; | |
183 | } | |
184 | /* The caller didn't request that the event be caught, | |
185 | relay the event to the next containing | |
186 | catch_errors(). */ | |
187 | catcher_pop (); | |
2a78bfb5 | 188 | throw_exception (exception); |
db5f402d AC |
189 | } |
190 | default: | |
e2e0b3e5 | 191 | internal_error (__FILE__, __LINE__, _("bad state")); |
db5f402d AC |
192 | } |
193 | default: | |
e2e0b3e5 | 194 | internal_error (__FILE__, __LINE__, _("bad switch")); |
db5f402d AC |
195 | } |
196 | } | |
60250e8b | 197 | |
6941d02a AC |
198 | int |
199 | exceptions_state_mc_action_iter (void) | |
200 | { | |
201 | return exceptions_state_mc (CATCH_ITER); | |
202 | } | |
203 | ||
204 | int | |
205 | exceptions_state_mc_action_iter_1 (void) | |
206 | { | |
207 | return exceptions_state_mc (CATCH_ITER_1); | |
208 | } | |
209 | ||
2a78bfb5 | 210 | /* Return EXCEPTION to the nearest containing catch_errors(). */ |
60250e8b AC |
211 | |
212 | NORETURN void | |
71fff37b | 213 | throw_exception (struct gdb_exception exception) |
60250e8b AC |
214 | { |
215 | quit_flag = 0; | |
216 | immediate_quit = 0; | |
217 | ||
218 | /* Perhaps it would be cleaner to do this via the cleanup chain (not sure | |
219 | I can think of a reason why that is vital, though). */ | |
220 | bpstat_clear_actions (stop_bpstat); /* Clear queued breakpoint commands */ | |
221 | ||
222 | disable_current_display (); | |
223 | do_cleanups (ALL_CLEANUPS); | |
224 | if (target_can_async_p () && !target_executing) | |
225 | do_exec_cleanups (ALL_CLEANUPS); | |
226 | if (sync_execution) | |
227 | do_exec_error_cleanups (ALL_CLEANUPS); | |
228 | ||
60250e8b AC |
229 | /* Jump to the containing catch_errors() call, communicating REASON |
230 | to that call via setjmp's return value. Note that REASON can't | |
231 | be zero, by definition in defs.h. */ | |
6941d02a | 232 | exceptions_state_mc (CATCH_THROWING); |
2a78bfb5 | 233 | *current_catcher->exception = exception; |
6941d02a | 234 | EXCEPTIONS_SIGLONGJMP (current_catcher->buf, exception.reason); |
2a78bfb5 AC |
235 | } |
236 | ||
6b1b7650 AC |
237 | static char *last_message; |
238 | ||
2a78bfb5 | 239 | NORETURN void |
315a522e | 240 | deprecated_throw_reason (enum return_reason reason) |
2a78bfb5 | 241 | { |
71fff37b | 242 | struct gdb_exception exception; |
2a78bfb5 AC |
243 | memset (&exception, 0, sizeof exception); |
244 | ||
245 | exception.reason = reason; | |
246 | switch (reason) | |
247 | { | |
248 | case RETURN_QUIT: | |
249 | break; | |
250 | case RETURN_ERROR: | |
251 | exception.error = GENERIC_ERROR; | |
2a78bfb5 AC |
252 | break; |
253 | default: | |
e2e0b3e5 | 254 | internal_error (__FILE__, __LINE__, _("bad switch")); |
2a78bfb5 AC |
255 | } |
256 | ||
257 | throw_exception (exception); | |
60250e8b AC |
258 | } |
259 | ||
6b1b7650 | 260 | static void |
c6da7a6d | 261 | print_flush (void) |
6b1b7650 | 262 | { |
e06e2353 AC |
263 | struct serial *gdb_stdout_serial; |
264 | ||
c6da7a6d AC |
265 | if (deprecated_error_begin_hook) |
266 | deprecated_error_begin_hook (); | |
267 | target_terminal_ours (); | |
e06e2353 AC |
268 | |
269 | /* We want all output to appear now, before we print the error. We | |
270 | have 3 levels of buffering we have to flush (it's possible that | |
271 | some of these should be changed to flush the lower-level ones | |
272 | too): */ | |
273 | ||
274 | /* 1. The _filtered buffer. */ | |
275 | wrap_here (""); | |
276 | ||
277 | /* 2. The stdio buffer. */ | |
c6da7a6d | 278 | gdb_flush (gdb_stdout); |
e06e2353 AC |
279 | gdb_flush (gdb_stderr); |
280 | ||
281 | /* 3. The system-level buffer. */ | |
282 | gdb_stdout_serial = serial_fdopen (1); | |
cade9e54 PB |
283 | if (gdb_stdout_serial) |
284 | { | |
285 | serial_drain_output (gdb_stdout_serial); | |
286 | serial_un_fdopen (gdb_stdout_serial); | |
287 | } | |
e06e2353 | 288 | |
c6da7a6d | 289 | annotate_error_begin (); |
6b1b7650 AC |
290 | } |
291 | ||
9cbc821d | 292 | static void |
71fff37b | 293 | print_exception (struct ui_file *file, struct gdb_exception e) |
9cbc821d AC |
294 | { |
295 | /* KLUGE: cagney/2005-01-13: Write the string out one line at a time | |
296 | as that way the MI's behavior is preserved. */ | |
297 | const char *start; | |
298 | const char *end; | |
299 | for (start = e.message; start != NULL; start = end) | |
300 | { | |
301 | end = strchr (start, '\n'); | |
302 | if (end == NULL) | |
303 | fputs_filtered (start, file); | |
304 | else | |
305 | { | |
306 | end++; | |
307 | ui_file_write (file, start, end - start); | |
308 | } | |
309 | } | |
c6da7a6d | 310 | fprintf_filtered (file, "\n"); |
e48f5bee AC |
311 | |
312 | /* Now append the annotation. */ | |
313 | switch (e.reason) | |
314 | { | |
315 | case RETURN_QUIT: | |
316 | annotate_quit (); | |
317 | break; | |
318 | case RETURN_ERROR: | |
319 | /* Assume that these are all errors. */ | |
320 | annotate_error (); | |
321 | break; | |
322 | default: | |
323 | internal_error (__FILE__, __LINE__, _("Bad switch.")); | |
324 | } | |
9cbc821d AC |
325 | } |
326 | ||
8a076db9 | 327 | void |
71fff37b | 328 | exception_print (struct ui_file *file, struct gdb_exception e) |
8a076db9 AC |
329 | { |
330 | if (e.reason < 0 && e.message != NULL) | |
331 | { | |
c6da7a6d | 332 | print_flush (); |
9cbc821d | 333 | print_exception (file, e); |
9cbc821d AC |
334 | } |
335 | } | |
8a076db9 | 336 | |
9cbc821d | 337 | void |
71fff37b | 338 | exception_fprintf (struct ui_file *file, struct gdb_exception e, |
9cbc821d AC |
339 | const char *prefix, ...) |
340 | { | |
341 | if (e.reason < 0 && e.message != NULL) | |
342 | { | |
343 | va_list args; | |
c6da7a6d AC |
344 | |
345 | print_flush (); | |
9cbc821d AC |
346 | |
347 | /* Print the prefix. */ | |
348 | va_start (args, prefix); | |
349 | vfprintf_filtered (file, prefix, args); | |
350 | va_end (args); | |
351 | ||
352 | print_exception (file, e); | |
8a076db9 AC |
353 | } |
354 | } | |
355 | ||
e48f5bee AC |
356 | void |
357 | print_any_exception (struct ui_file *file, const char *prefix, | |
71fff37b | 358 | struct gdb_exception e) |
e48f5bee AC |
359 | { |
360 | if (e.reason < 0 && e.message != NULL) | |
361 | { | |
362 | target_terminal_ours (); | |
363 | wrap_here (""); /* Force out any buffered output */ | |
364 | gdb_flush (gdb_stdout); | |
365 | annotate_error_begin (); | |
366 | ||
367 | /* Print the prefix. */ | |
368 | if (prefix != NULL && prefix[0] != '\0') | |
369 | fputs_filtered (prefix, file); | |
370 | print_exception (file, e); | |
371 | } | |
372 | } | |
373 | ||
bee0189a | 374 | NORETURN static void ATTR_NORETURN ATTR_FORMAT (printf, 3, 0) |
3af1e0e3 AC |
375 | throw_it (enum return_reason reason, enum errors error, const char *fmt, |
376 | va_list ap) | |
6b1b7650 | 377 | { |
71fff37b | 378 | struct gdb_exception e; |
17d92a02 | 379 | char *new_message; |
6b1b7650 | 380 | |
17d92a02 AC |
381 | /* Save the message. Create the new message before deleting the |
382 | old, the new message may include the old message text. */ | |
383 | new_message = xstrvprintf (fmt, ap); | |
6b1b7650 | 384 | xfree (last_message); |
17d92a02 | 385 | last_message = new_message; |
c6da7a6d AC |
386 | |
387 | /* Create the exception. */ | |
388 | e.reason = reason; | |
389 | e.error = error; | |
390 | e.message = last_message; | |
6b1b7650 | 391 | |
6b1b7650 | 392 | /* Throw the exception. */ |
6b1b7650 AC |
393 | throw_exception (e); |
394 | } | |
395 | ||
396 | NORETURN void | |
397 | throw_verror (enum errors error, const char *fmt, va_list ap) | |
398 | { | |
3af1e0e3 | 399 | throw_it (RETURN_ERROR, error, fmt, ap); |
6b1b7650 AC |
400 | } |
401 | ||
402 | NORETURN void | |
403 | throw_vfatal (const char *fmt, va_list ap) | |
404 | { | |
7b871fab | 405 | throw_it (RETURN_QUIT, GDB_NO_ERROR, fmt, ap); |
6b1b7650 AC |
406 | } |
407 | ||
408 | NORETURN void | |
05ff989b | 409 | throw_error (enum errors error, const char *fmt, ...) |
6b1b7650 | 410 | { |
05ff989b AC |
411 | va_list args; |
412 | va_start (args, fmt); | |
3af1e0e3 | 413 | throw_it (RETURN_ERROR, error, fmt, args); |
05ff989b | 414 | va_end (args); |
6b1b7650 AC |
415 | } |
416 | ||
60250e8b AC |
417 | /* Call FUNC() with args FUNC_UIOUT and FUNC_ARGS, catching any |
418 | errors. Set FUNC_CAUGHT to an ``enum return_reason'' if the | |
419 | function is aborted (using throw_exception() or zero if the | |
420 | function returns normally. Set FUNC_VAL to the value returned by | |
421 | the function or 0 if the function was aborted. | |
422 | ||
423 | Must not be called with immediate_quit in effect (bad things might | |
424 | happen, say we got a signal in the middle of a memcpy to quit_return). | |
425 | This is an OK restriction; with very few exceptions immediate_quit can | |
426 | be replaced by judicious use of QUIT. | |
427 | ||
428 | MASK specifies what to catch; it is normally set to | |
429 | RETURN_MASK_ALL, if for no other reason than that the code which | |
430 | calls catch_errors might not be set up to deal with a quit which | |
431 | isn't caught. But if the code can deal with it, it generally | |
432 | should be RETURN_MASK_ERROR, unless for some reason it is more | |
433 | useful to abort only the portion of the operation inside the | |
434 | catch_errors. Note that quit should return to the command line | |
435 | fairly quickly, even if some further processing is being done. */ | |
436 | ||
437 | /* MAYBE: cagney/1999-11-05: catch_errors() in conjunction with | |
438 | error() et.al. could maintain a set of flags that indicate the the | |
439 | current state of each of the longjmp buffers. This would give the | |
440 | longjmp code the chance to detect a longjmp botch (before it gets | |
441 | to longjmperror()). Prior to 1999-11-05 this wasn't possible as | |
442 | code also randomly used a SET_TOP_LEVEL macro that directly | |
443 | initialize the longjmp buffers. */ | |
444 | ||
445 | /* MAYBE: cagney/1999-11-05: Should the catch_errors and cleanups code | |
446 | be consolidated into a single file instead of being distributed | |
447 | between utils.c and top.c? */ | |
448 | ||
60250e8b AC |
449 | int |
450 | catch_exceptions (struct ui_out *uiout, | |
451 | catch_exceptions_ftype *func, | |
452 | void *func_args, | |
60250e8b AC |
453 | return_mask mask) |
454 | { | |
1c3c7ee7 | 455 | return catch_exceptions_with_msg (uiout, func, func_args, NULL, mask); |
60250e8b AC |
456 | } |
457 | ||
71fff37b | 458 | struct gdb_exception |
2a78bfb5 AC |
459 | catch_exception (struct ui_out *uiout, |
460 | catch_exception_ftype *func, | |
461 | void *func_args, | |
462 | return_mask mask) | |
463 | { | |
71fff37b | 464 | volatile struct gdb_exception exception; |
6941d02a AC |
465 | TRY_CATCH (exception, mask) |
466 | { | |
467 | (*func) (uiout, func_args); | |
468 | } | |
2a78bfb5 AC |
469 | return exception; |
470 | } | |
471 | ||
60250e8b AC |
472 | int |
473 | catch_exceptions_with_msg (struct ui_out *uiout, | |
474 | catch_exceptions_ftype *func, | |
475 | void *func_args, | |
60250e8b AC |
476 | char **gdberrmsg, |
477 | return_mask mask) | |
478 | { | |
71fff37b | 479 | volatile struct gdb_exception exception; |
2a78bfb5 | 480 | volatile int val = 0; |
6941d02a AC |
481 | TRY_CATCH (exception, mask) |
482 | { | |
483 | val = (*func) (uiout, func_args); | |
484 | } | |
e48f5bee | 485 | print_any_exception (gdb_stderr, NULL, exception); |
60250e8b | 486 | gdb_assert (val >= 0); |
2a78bfb5 AC |
487 | gdb_assert (exception.reason <= 0); |
488 | if (exception.reason < 0) | |
489 | { | |
490 | /* If caller wants a copy of the low-level error message, make | |
491 | one. This is used in the case of a silent error whereby the | |
492 | caller may optionally want to issue the message. */ | |
493 | if (gdberrmsg != NULL) | |
6b1b7650 AC |
494 | { |
495 | if (exception.message != NULL) | |
496 | *gdberrmsg = xstrdup (exception.message); | |
497 | else | |
498 | *gdberrmsg = NULL; | |
499 | } | |
2a78bfb5 AC |
500 | return exception.reason; |
501 | } | |
60250e8b AC |
502 | return val; |
503 | } | |
504 | ||
60250e8b AC |
505 | int |
506 | catch_errors (catch_errors_ftype *func, void *func_args, char *errstring, | |
507 | return_mask mask) | |
508 | { | |
2a78bfb5 | 509 | volatile int val = 0; |
71fff37b | 510 | volatile struct gdb_exception exception; |
6941d02a AC |
511 | TRY_CATCH (exception, mask) |
512 | { | |
513 | val = func (func_args); | |
514 | } | |
e48f5bee | 515 | print_any_exception (gdb_stderr, errstring, exception); |
2a78bfb5 | 516 | if (exception.reason != 0) |
60250e8b AC |
517 | return 0; |
518 | return val; | |
519 | } | |
520 | ||
60250e8b AC |
521 | int |
522 | catch_command_errors (catch_command_errors_ftype * command, | |
523 | char *arg, int from_tty, return_mask mask) | |
524 | { | |
71fff37b | 525 | volatile struct gdb_exception e; |
6941d02a AC |
526 | TRY_CATCH (e, mask) |
527 | { | |
528 | command (arg, from_tty); | |
529 | } | |
5a14cc1a AC |
530 | print_any_exception (gdb_stderr, NULL, e); |
531 | if (e.reason < 0) | |
532 | return 0; | |
533 | return 1; | |
60250e8b | 534 | } |