7b4ac7e1 |
1 | /* Start and stop the inferior process, for GDB. |
632ea0cc |
2 | Copyright (C) 1986, 1987, 1988 Free Software Foundation, Inc. |
7b4ac7e1 |
3 | |
4 | GDB is distributed in the hope that it will be useful, but WITHOUT ANY |
5 | WARRANTY. No author or distributor accepts responsibility to anyone |
6 | for the consequences of using it or for whether it serves any |
7 | particular purpose or works at all, unless he says so in writing. |
8 | Refer to the GDB General Public License for full details. |
9 | |
10 | Everyone is granted permission to copy, modify and redistribute GDB, |
11 | but only under the conditions described in the GDB General Public |
12 | License. A copy of this license is supposed to have been given to you |
13 | along with GDB so you can know your rights and responsibilities. It |
14 | should be in a file named COPYING. Among other things, the copyright |
15 | notice and this notice must be preserved on all copies. |
16 | |
17 | In other words, go ahead and share GDB, but don't try to stop |
18 | anyone else from sharing it farther. Help stamp out software hoarding! |
19 | */ |
20 | |
21 | #include "defs.h" |
22 | #include "initialize.h" |
23 | #include "param.h" |
24 | #include "symtab.h" |
25 | #include "frame.h" |
26 | #include "inferior.h" |
27 | #include "wait.h" |
28 | |
29 | #include <stdio.h> |
30 | #include <signal.h> |
31 | #include <a.out.h> |
32 | |
33 | #ifdef UMAX_PTRACE |
34 | #include <sys/param.h> |
35 | #include <sys/ptrace.h> |
36 | #endif UMAX_PTRACE |
37 | |
38 | extern char *sys_siglist[]; |
39 | extern int errno; |
40 | |
41 | /* Tables of how to react to signals; the user sets them. */ |
42 | |
43 | static char signal_stop[NSIG]; |
44 | static char signal_print[NSIG]; |
45 | static char signal_program[NSIG]; |
46 | |
47 | /* Nonzero if breakpoints are now inserted in the inferior. */ |
48 | |
49 | static int breakpoints_inserted; |
50 | |
51 | /* Function inferior was in as of last step command. */ |
52 | |
53 | static struct symbol *step_start_function; |
54 | |
55 | /* This is the sequence of bytes we insert for a breakpoint. */ |
56 | |
57 | static char break_insn[] = BREAKPOINT; |
58 | |
59 | /* Nonzero => address for special breakpoint for resuming stepping. */ |
60 | |
61 | static CORE_ADDR step_resume_break_address; |
62 | |
63 | /* Original contents of the byte where the special breakpoint is. */ |
64 | |
65 | static char step_resume_break_shadow[sizeof break_insn]; |
66 | |
67 | /* Nonzero means the special breakpoint is a duplicate |
68 | so it has not itself been inserted. */ |
69 | |
70 | static int step_resume_break_duplicate; |
71 | |
72 | /* Nonzero if we are expecting a trace trap and should proceed from it. |
73 | 2 means expecting 2 trace traps and should continue both times. |
74 | That occurs when we tell sh to exec the program: we will get |
75 | a trap after the exec of sh and a second when the program is exec'd. */ |
76 | |
77 | static int trap_expected; |
78 | |
79 | /* Nonzero means expecting a trace trap |
80 | and should stop the inferior and return silently when it happens. */ |
81 | |
82 | static int stop_after_trap; |
83 | |
84 | /* Nonzero means expecting a trace trap due to attaching to a process. */ |
85 | |
86 | static int stop_after_attach; |
87 | |
88 | /* Nonzero if pc has been changed by the debugger |
89 | since the inferior stopped. */ |
90 | |
91 | int pc_changed; |
92 | |
632ea0cc |
93 | /* Nonzero if debugging a remote machine via a serial link or ethernet. */ |
94 | |
95 | int remote_debugging; |
96 | |
7b4ac7e1 |
97 | /* Save register contents here when about to pop a stack dummy frame. */ |
98 | |
99 | char stop_registers[REGISTER_BYTES]; |
100 | |
101 | /* Nonzero if program stopped due to error trying to insert breakpoints. */ |
102 | |
103 | static int breakpoints_failed; |
104 | |
105 | /* Nonzero if inferior is in sh before our program got exec'd. */ |
106 | |
107 | static int running_in_shell; |
108 | |
109 | /* Nonzero after stop if current stack frame should be printed. */ |
110 | |
111 | static int stop_print_frame; |
112 | |
113 | static void insert_step_breakpoint (); |
114 | static void remove_step_breakpoint (); |
115 | static void wait_for_inferior (); |
116 | static void normal_stop (); |
117 | |
118 | START_FILE |
119 | \f |
120 | /* Clear out all variables saying what to do when inferior is continued. |
121 | First do this, then set the ones you want, then call `proceed'. */ |
122 | |
123 | void |
124 | clear_proceed_status () |
125 | { |
126 | trap_expected = 0; |
127 | step_range_start = 0; |
128 | step_range_end = 0; |
129 | step_frame = 0; |
130 | step_over_calls = -1; |
131 | step_resume_break_address = 0; |
132 | stop_after_trap = 0; |
133 | stop_after_attach = 0; |
134 | |
135 | /* Discard any remaining commands left by breakpoint we had stopped at. */ |
136 | clear_breakpoint_commands (); |
137 | } |
138 | |
139 | /* Basic routine for continuing the program in various fashions. |
140 | |
141 | ADDR is the address to resume at, or -1 for resume where stopped. |
142 | SIGNAL is the signal to give it, or 0 for none, |
143 | or -1 for act according to how it stopped. |
144 | STEP is nonzero if should trap after one instruction. |
145 | -1 means return after that and print nothing. |
146 | You should probably set various step_... variables |
147 | before calling here, if you are stepping. |
148 | |
149 | You should call clear_proceed_status before calling proceed. */ |
150 | |
151 | void |
152 | proceed (addr, signal, step) |
153 | CORE_ADDR addr; |
154 | int signal; |
155 | int step; |
156 | { |
157 | int oneproc = 0; |
158 | |
159 | if (step > 0) |
160 | step_start_function = find_pc_function (read_pc ()); |
161 | if (step < 0) |
162 | stop_after_trap = 1; |
163 | |
164 | if (addr == -1) |
165 | { |
166 | /* If there is a breakpoint at the address we will resume at, |
167 | step one instruction before inserting breakpoints |
168 | so that we do not stop right away. */ |
169 | |
170 | if (!pc_changed && breakpoint_here_p (read_pc ())) |
171 | { |
172 | oneproc = 1; |
173 | /* We will get a trace trap after one instruction. |
174 | Continue it automatically and insert breakpoints then. */ |
175 | trap_expected = 1; |
176 | } |
177 | } |
178 | else |
179 | write_register (PC_REGNUM, addr); |
180 | |
181 | if (!oneproc) |
182 | { |
183 | int temp = insert_breakpoints (); |
184 | if (temp) |
185 | { |
186 | print_sys_errmsg ("ptrace", temp); |
187 | error ("Cannot insert breakpoints.\n\ |
188 | The same program may be running in another process."); |
189 | } |
190 | breakpoints_inserted = 1; |
191 | } |
192 | |
193 | /* Install inferior's terminal modes. */ |
194 | terminal_inferior (); |
195 | |
196 | if (signal >= 0) |
197 | stop_signal = signal; |
198 | /* If this signal should not be seen by program, |
199 | give it zero. Used for debugging signals. */ |
200 | else if (stop_signal < NSIG && !signal_program[stop_signal]) |
201 | stop_signal= 0; |
202 | |
203 | /* Resume inferior. */ |
204 | resume (oneproc || step, stop_signal); |
205 | |
206 | /* Wait for it to stop (if not standalone) |
207 | and in any case decode why it stopped, and act accordingly. */ |
208 | |
209 | wait_for_inferior (); |
210 | normal_stop (); |
211 | } |
212 | |
213 | /* Writing the inferior pc as a register calls this function |
214 | to inform infrun that the pc has been set in the debugger. */ |
215 | |
216 | writing_pc (val) |
217 | CORE_ADDR val; |
218 | { |
219 | stop_pc = val; |
220 | pc_changed = 1; |
221 | } |
222 | |
223 | /* Start an inferior process for the first time. |
224 | Actually it was started by the fork that created it, |
225 | but it will have stopped one instruction after execing sh. |
226 | Here we must get it up to actual execution of the real program. */ |
227 | |
228 | start_inferior () |
229 | { |
230 | /* We will get a trace trap after one instruction. |
231 | Continue it automatically. Eventually (after shell does an exec) |
232 | it will get another trace trap. Then insert breakpoints and continue. */ |
233 | trap_expected = 2; |
234 | running_in_shell = 0; /* Set to 1 at first SIGTRAP, 0 at second. */ |
235 | breakpoints_inserted = 0; |
236 | mark_breakpoints_out (); |
237 | |
238 | /* Set up the "saved terminal modes" of the inferior |
239 | based on what modes we are starting it with. */ |
240 | terminal_init_inferior (); |
241 | |
242 | /* Install inferior's terminal modes. */ |
243 | terminal_inferior (); |
244 | |
632ea0cc |
245 | if (remote_debugging) |
246 | { |
247 | trap_expected = 0; |
248 | fetch_inferior_registers(); |
249 | set_current_frame (read_register(FP_REGNUM)); |
250 | stop_frame = get_current_frame(); |
251 | inferior_pid = 3; |
252 | if (insert_breakpoints()) |
253 | fatal("Can't insert breakpoints"); |
254 | breakpoints_inserted = 1; |
255 | proceed(-1, -1, 0); |
256 | } |
257 | else |
258 | { |
259 | wait_for_inferior (); |
260 | normal_stop (); |
261 | } |
262 | } |
263 | |
264 | /* Start remote-debugging of a machine over a serial link. */ |
265 | |
266 | void |
267 | start_remote () |
268 | { |
269 | clear_proceed_status (); |
270 | running_in_shell = 0; |
271 | trap_expected = 0; |
272 | inferior_pid = 3; |
273 | breakpoints_inserted = 0; |
274 | mark_breakpoints_out (); |
7b4ac7e1 |
275 | wait_for_inferior (); |
632ea0cc |
276 | normal_stop(); |
7b4ac7e1 |
277 | } |
278 | |
279 | #ifdef ATTACH_DETACH |
280 | |
281 | /* Attach to process PID, then initialize for debugging it |
282 | and wait for the trace-trap that results from attaching. */ |
283 | |
284 | void |
285 | attach_program (pid) |
286 | int pid; |
287 | { |
288 | attach (pid); |
289 | inferior_pid = pid; |
290 | |
291 | mark_breakpoints_out (); |
292 | terminal_init_inferior (); |
293 | clear_proceed_status (); |
294 | stop_after_attach = 1; |
295 | /*proceed (-1, 0, -2);*/ |
296 | wait_for_inferior (); |
297 | normal_stop (); |
298 | } |
299 | #endif /* ATTACH_DETACH */ |
300 | \f |
301 | /* Wait for control to return from inferior to debugger. |
302 | If inferior gets a signal, we may decide to start it up again |
303 | instead of returning. That is why there is a loop in this function. |
304 | When this function actually returns it means the inferior |
305 | should be left stopped and GDB should read more commands. */ |
306 | |
307 | static void |
308 | wait_for_inferior () |
309 | { |
310 | register int pid; |
311 | WAITTYPE w; |
312 | CORE_ADDR pc; |
313 | int tem; |
314 | int another_trap; |
315 | int random_signal; |
316 | CORE_ADDR stop_sp; |
317 | int stop_step_resume_break; |
318 | int newmisc; |
319 | int newfun_pc; |
320 | struct symbol *newfun; |
321 | struct symtab_and_line sal; |
322 | int prev_pc; |
323 | |
324 | while (1) |
325 | { |
326 | prev_pc = read_pc (); |
632ea0cc |
327 | |
328 | if (remote_debugging) |
329 | remote_wait (&w); |
330 | else |
331 | { |
332 | pid = wait (&w); |
333 | if (pid != inferior_pid) |
334 | continue; |
335 | } |
336 | |
7b4ac7e1 |
337 | pc_changed = 0; |
338 | fetch_inferior_registers (); |
339 | stop_pc = read_pc (); |
340 | set_current_frame (read_register (FP_REGNUM)); |
341 | stop_frame = get_current_frame (); |
342 | stop_sp = read_register (SP_REGNUM); |
343 | another_trap = 0; |
344 | stop_breakpoint = 0; |
345 | stop_step = 0; |
346 | stop_stack_dummy = 0; |
347 | stop_print_frame = 1; |
348 | stop_step_resume_break = 0; |
349 | random_signal = 0; |
350 | breakpoints_failed = 0; |
351 | |
352 | /* Look at the cause of the stop, and decide what to do. |
353 | The alternatives are: |
354 | 1) break; to really stop and return to the debugger, |
355 | 2) drop through to start up again |
356 | (set another_trap to 1 to single step once) |
357 | 3) set random_signal to 1, and the decision between 1 and 2 |
358 | will be made according to the signal handling tables. */ |
359 | |
360 | if (WIFEXITED (w)) |
361 | { |
362 | terminal_ours_for_output (); |
363 | if (WRETCODE (w)) |
364 | printf ("\nProgram exited with code 0%o.\n", WRETCODE (w)); |
365 | else |
366 | printf ("\nProgram exited normally.\n"); |
367 | fflush (stdout); |
368 | inferior_died (); |
369 | stop_print_frame = 0; |
370 | break; |
371 | } |
372 | else if (!WIFSTOPPED (w)) |
373 | { |
374 | kill_inferior (); |
375 | stop_print_frame = 0; |
376 | stop_signal = WTERMSIG (w); |
377 | terminal_ours_for_output (); |
378 | printf ("\nProgram terminated with signal %d, %s\n", |
379 | stop_signal, |
380 | stop_signal < NSIG |
381 | ? sys_siglist[stop_signal] |
382 | : "(undocumented)"); |
383 | printf ("The inferior process no longer exists.\n"); |
384 | fflush (stdout); |
385 | break; |
386 | } |
387 | else |
388 | { |
389 | stop_signal = WSTOPSIG (w); |
390 | |
391 | /* First, distinguish signals caused by the debugger from signals |
392 | that have to do with the program's own actions. |
393 | Note that breakpoint insns may cause SIGTRAP or SIGILL |
394 | or SIGEMT, depending on the operating system version. |
395 | Here we detect when a SIGILL or SIGEMT is really a breakpoint |
396 | and change it to SIGTRAP. */ |
397 | |
398 | if (stop_signal == SIGTRAP |
399 | || (breakpoints_inserted && |
400 | (stop_signal == SIGILL |
401 | || stop_signal == SIGEMT)) |
402 | || stop_after_attach) |
403 | { |
404 | if (stop_signal == SIGTRAP && stop_after_trap) |
405 | { |
406 | stop_print_frame = 0; |
407 | break; |
408 | } |
409 | if (stop_after_attach) |
410 | break; |
411 | /* Don't even think about breakpoints |
412 | if still running the shell that will exec the program |
413 | or if just proceeded over a breakpoint. */ |
414 | if (stop_signal == SIGTRAP && trap_expected) |
415 | stop_breakpoint = 0; |
416 | else |
417 | /* See if there is a breakpoint at the current PC. */ |
418 | #if DECR_PC_AFTER_BREAK |
419 | /* Notice the case of stepping through a jump |
420 | that leads just after a breakpoint. |
421 | Don't confuse that with hitting the breakpoint. |
422 | What we check for is that 1) stepping is going on |
423 | and 2) the pc before the last insn does not match |
424 | the address of the breakpoint before the current pc. */ |
425 | if (!(prev_pc != stop_pc - DECR_PC_AFTER_BREAK |
426 | && step_range_end && !step_resume_break_address)) |
427 | #endif /* DECR_PC_AFTER_BREAK not zero */ |
428 | { |
429 | select_frame (stop_frame, 0); /* For condition exprs. */ |
430 | stop_breakpoint = breakpoint_stop_status (stop_pc, stop_frame); |
431 | /* Following in case break condition called a function. */ |
432 | stop_print_frame = 1; |
433 | if (stop_breakpoint && DECR_PC_AFTER_BREAK) |
434 | { |
435 | stop_pc -= DECR_PC_AFTER_BREAK; |
436 | write_register (PC_REGNUM, stop_pc); |
437 | pc_changed = 0; |
438 | } |
439 | } |
440 | /* See if we stopped at the special breakpoint for |
441 | stepping over a subroutine call. */ |
442 | if (stop_pc - DECR_PC_AFTER_BREAK == step_resume_break_address) |
443 | { |
444 | stop_step_resume_break = 1; |
445 | if (DECR_PC_AFTER_BREAK) |
446 | { |
447 | stop_pc -= DECR_PC_AFTER_BREAK; |
448 | write_register (PC_REGNUM, stop_pc); |
449 | pc_changed = 0; |
450 | } |
451 | } |
452 | |
453 | if (stop_signal == SIGTRAP) |
454 | random_signal |
455 | = !(stop_breakpoint || trap_expected |
456 | || stop_step_resume_break |
457 | || (stop_sp INNER_THAN stop_pc && stop_pc INNER_THAN stop_frame) |
458 | || (step_range_end && !step_resume_break_address)); |
459 | else |
460 | { |
461 | random_signal |
462 | = !(stop_breakpoint || stop_step_resume_break); |
463 | if (!random_signal) |
464 | stop_signal = SIGTRAP; |
465 | } |
466 | } |
467 | else |
468 | random_signal = 1; |
469 | |
470 | /* For the program's own signals, act according to |
471 | the signal handling tables. */ |
472 | |
473 | if (random_signal |
474 | && !(running_in_shell && stop_signal == SIGSEGV)) |
475 | { |
476 | /* Signal not for debugging purposes. */ |
477 | int printed = 0; |
478 | |
479 | if (stop_signal >= NSIG |
480 | || signal_print[stop_signal]) |
481 | { |
482 | printed = 1; |
483 | terminal_ours_for_output (); |
484 | printf ("\nProgram received signal %d, %s\n", |
485 | stop_signal, |
486 | stop_signal < NSIG |
487 | ? sys_siglist[stop_signal] |
488 | : "(undocumented)"); |
489 | fflush (stdout); |
490 | } |
491 | if (stop_signal >= NSIG |
492 | || signal_stop[stop_signal]) |
493 | break; |
494 | /* If not going to stop, give terminal back |
495 | if we took it away. */ |
496 | else if (printed) |
497 | terminal_inferior (); |
498 | } |
499 | |
500 | /* Handle cases caused by hitting a breakpoint. */ |
501 | |
502 | if (!random_signal |
503 | && (stop_breakpoint || stop_step_resume_break)) |
504 | { |
505 | /* Does a breakpoint want us to stop? */ |
506 | if (stop_breakpoint && stop_breakpoint != -1) |
507 | { |
508 | /* 0x1000000 is set in stop_breakpoint as returned by |
509 | breakpoint_status_p to indicate a silent breakpoint. */ |
510 | if (stop_breakpoint > 0 && stop_breakpoint & 0x1000000) |
511 | { |
512 | stop_breakpoint &= ~0x1000000; |
513 | stop_print_frame = 0; |
514 | } |
515 | break; |
516 | } |
517 | /* But if we have hit the step-resumption breakpoint, |
518 | remove it. It has done its job getting us here. */ |
519 | if (stop_step_resume_break |
520 | && (step_frame == 0 || stop_frame == step_frame)) |
521 | { |
522 | remove_step_breakpoint (); |
523 | step_resume_break_address = 0; |
524 | } |
525 | /* Otherwise, must remove breakpoints and single-step |
526 | to get us past the one we hit. */ |
527 | else |
528 | { |
529 | remove_breakpoints (); |
530 | remove_step_breakpoint (); |
531 | breakpoints_inserted = 0; |
532 | another_trap = 1; |
533 | } |
534 | |
535 | /* We come here if we hit a breakpoint but should not |
536 | stop for it. Possibly we also were stepping |
537 | and should stop for that. So fall through and |
538 | test for stepping. But, if not stepping, |
539 | do not stop. */ |
540 | } |
541 | |
542 | /* If this is the breakpoint at the end of a stack dummy, |
543 | just stop silently. */ |
544 | if (stop_sp INNER_THAN stop_pc && stop_pc INNER_THAN stop_frame) |
545 | { |
546 | stop_print_frame = 0; |
547 | stop_stack_dummy = 1; |
548 | break; |
549 | } |
550 | |
551 | if (step_resume_break_address) |
552 | /* Having a step-resume breakpoint overrides anything |
553 | else having to do with stepping commands until |
554 | that breakpoint is reached. */ |
555 | ; |
556 | /* If stepping through a line, keep going if still within it. */ |
557 | else if (!random_signal |
558 | && step_range_end |
559 | && stop_pc >= step_range_start |
560 | && stop_pc < step_range_end) |
561 | { |
562 | /* Don't step through the return from a function |
563 | unless that is the first instruction stepped through. */ |
564 | if (ABOUT_TO_RETURN (stop_pc)) |
565 | { |
566 | stop_step = 1; |
567 | break; |
568 | } |
569 | } |
570 | |
571 | /* We stepped out of the stepping range. See if that was due |
572 | to a subroutine call that we should proceed to the end of. */ |
573 | else if (!random_signal && step_range_end) |
574 | { |
575 | newfun = find_pc_function (stop_pc); |
632ea0cc |
576 | newmisc = -1; |
7b4ac7e1 |
577 | if (newfun) |
578 | { |
579 | newfun_pc = BLOCK_START (SYMBOL_BLOCK_VALUE (newfun)) |
580 | + FUNCTION_START_OFFSET; |
581 | } |
582 | else |
583 | { |
584 | newmisc = find_pc_misc_function (stop_pc); |
585 | if (newmisc >= 0) |
586 | newfun_pc = misc_function_vector[newmisc].address |
587 | + FUNCTION_START_OFFSET; |
588 | else newfun_pc = 0; |
589 | } |
590 | if (stop_pc == newfun_pc |
591 | && (step_over_calls > 0 || (step_over_calls && newfun == 0))) |
592 | { |
593 | /* A subroutine call has happened. */ |
594 | /* Set a special breakpoint after the return */ |
595 | step_resume_break_address = SAVED_PC_AFTER_CALL (stop_frame); |
596 | step_resume_break_duplicate |
597 | = breakpoint_here_p (step_resume_break_address); |
598 | if (breakpoints_inserted) |
599 | insert_step_breakpoint (); |
600 | } |
601 | /* Subroutine call with source code we should not step over. |
602 | Do step to the first line of code in it. */ |
603 | else if (stop_pc == newfun_pc && step_over_calls) |
604 | { |
605 | SKIP_PROLOGUE (newfun_pc); |
606 | sal = find_pc_line (newfun_pc, 0); |
607 | /* Use the step_resume_break to step until |
608 | the end of the prologue, even if that involves jumps |
609 | (as it seems to on the vax under 4.2). */ |
610 | /* If the prologue ends in the middle of a source line, |
611 | continue to the end of that source line. |
612 | Otherwise, just go to end of prologue. */ |
613 | if (sal.end && sal.pc != newfun_pc) |
614 | step_resume_break_address = sal.end; |
615 | else |
616 | step_resume_break_address = newfun_pc; |
617 | |
618 | step_resume_break_duplicate |
619 | = breakpoint_here_p (step_resume_break_address); |
620 | if (breakpoints_inserted) |
621 | insert_step_breakpoint (); |
622 | /* Do not specify what the fp should be when we stop |
623 | since on some machines the prologue |
624 | is where the new fp value is established. */ |
625 | step_frame = 0; |
626 | /* And make sure stepping stops right away then. */ |
627 | step_range_end = step_range_start; |
628 | } |
629 | /* No subroutince call; stop now. */ |
630 | else |
631 | { |
632 | stop_step = 1; |
633 | break; |
634 | } |
635 | } |
636 | } |
637 | |
638 | /* If we did not do break;, it means we should keep |
639 | running the inferior and not return to debugger. */ |
640 | |
641 | /* If trap_expected is 2, it means continue once more |
642 | and insert breakpoints at the next trap. |
643 | If trap_expected is 1 and the signal was SIGSEGV, it means |
644 | the shell is doing some memory allocation--just resume it |
645 | with SIGSEGV. |
646 | Otherwise insert breakpoints now, and possibly single step. */ |
647 | |
648 | if (trap_expected > 1) |
649 | { |
650 | trap_expected--; |
651 | running_in_shell = 1; |
652 | resume (0, 0); |
653 | } |
654 | else if (running_in_shell && stop_signal == SIGSEGV) |
655 | { |
656 | resume (0, SIGSEGV); |
657 | } |
658 | else |
659 | { |
660 | /* Here, we are not awaiting another exec to get |
661 | the program we really want to debug. |
662 | Insert breakpoints now, unless we are trying |
663 | to one-proceed past a breakpoint. */ |
664 | running_in_shell = 0; |
665 | if (!breakpoints_inserted && !another_trap) |
666 | { |
667 | insert_step_breakpoint (); |
668 | breakpoints_failed = insert_breakpoints (); |
669 | if (breakpoints_failed) |
670 | break; |
671 | breakpoints_inserted = 1; |
672 | } |
673 | |
674 | trap_expected = another_trap; |
675 | |
676 | if (stop_signal == SIGTRAP) |
677 | stop_signal = 0; |
678 | |
679 | resume ((step_range_end && !step_resume_break_address) |
680 | || trap_expected, |
681 | stop_signal); |
682 | } |
683 | } |
684 | } |
685 | \f |
686 | /* Here to return control to GDB when the inferior stops for real. |
687 | Print appropriate messages, remove breakpoints, give terminal our modes. |
688 | |
689 | RUNNING_IN_SHELL nonzero means the shell got a signal before |
690 | exec'ing the program we wanted to run. |
691 | STOP_PRINT_FRAME nonzero means print the executing frame |
692 | (pc, function, args, file, line number and line text). |
693 | BREAKPOINTS_FAILED nonzero means stop was due to error |
694 | attempting to insert breakpoints. */ |
695 | |
696 | static void |
697 | normal_stop () |
698 | { |
699 | if (breakpoints_failed) |
700 | { |
701 | terminal_ours_for_output (); |
702 | print_sys_errmsg ("ptrace", breakpoints_failed); |
703 | printf ("Stopped; cannot insert breakpoints.\n\ |
704 | The same program may be running in another process.\n"); |
705 | } |
706 | |
707 | if (inferior_pid) |
708 | remove_step_breakpoint (); |
709 | |
710 | if (inferior_pid && breakpoints_inserted) |
711 | if (remove_breakpoints ()) |
712 | { |
713 | terminal_ours_for_output (); |
714 | printf ("Cannot remove breakpoints because program is no longer writable.\n\ |
715 | It must be running in another process.\n\ |
716 | Further execution is probably impossible.\n"); |
717 | } |
718 | |
719 | breakpoints_inserted = 0; |
720 | |
721 | /* Delete the breakpoint we stopped at, if it wants to be deleted. |
722 | Delete any breakpoint that is to be deleted at the next stop. */ |
723 | |
724 | breakpoint_auto_delete (stop_breakpoint); |
725 | |
726 | if (step_multi && stop_step) |
727 | return; |
728 | |
729 | terminal_ours (); |
730 | |
731 | if (running_in_shell) |
732 | { |
733 | if (stop_signal == SIGSEGV) |
734 | printf ("\ |
735 | You have just encountered a bug in \"sh\". GDB starts your program\n\ |
736 | by running \"sh\" with a command to exec your program.\n\ |
737 | This is so that \"sh\" will process wildcards and I/O redirection.\n\ |
738 | This time, \"sh\" crashed.\n\ |
739 | \n\ |
740 | One known bug in \"sh\" bites when the environment takes up a lot of space.\n\ |
741 | Try \"info env\" to see the environment; then use \"unset-env\" to kill\n\ |
742 | some variables whose values are large; then do \"run\" again.\n\ |
743 | \n\ |
744 | If that works, you might want to put those \"unset-env\" commands\n\ |
745 | into a \".gdbinit\" file in this directory so they will happen every time.\n"); |
746 | /* Don't confuse user with his program's symbols on sh's data. */ |
747 | stop_print_frame = 0; |
748 | } |
749 | |
750 | if (inferior_pid == 0) |
751 | return; |
752 | |
753 | /* Select innermost stack frame except on return from a stack dummy routine, |
754 | or if the program has exited. */ |
755 | if (!stop_stack_dummy) |
756 | { |
757 | select_frame (stop_frame, 0); |
758 | |
759 | if (stop_print_frame) |
760 | { |
761 | if (stop_breakpoint > 0) |
762 | printf ("\nBpt %d, ", stop_breakpoint); |
763 | print_sel_frame (stop_step |
764 | && step_frame == stop_frame |
765 | && step_start_function == find_pc_function (stop_pc)); |
766 | /* Display the auto-display expressions. */ |
767 | do_displays (); |
768 | } |
769 | } |
770 | |
771 | /* Save the function value return registers |
772 | We might be about to restore their previous contents. */ |
773 | read_register_bytes (0, stop_registers, REGISTER_BYTES); |
774 | |
775 | if (stop_stack_dummy) |
776 | { |
777 | /* Pop the empty frame that contains the stack dummy. */ |
778 | POP_FRAME; |
779 | select_frame (read_register (FP_REGNUM), 0); |
780 | } |
781 | } |
782 | \f |
783 | static void |
784 | insert_step_breakpoint () |
785 | { |
786 | if (step_resume_break_address && !step_resume_break_duplicate) |
787 | { |
788 | read_memory (step_resume_break_address, |
789 | step_resume_break_shadow, sizeof break_insn); |
790 | write_memory (step_resume_break_address, |
791 | break_insn, sizeof break_insn); |
792 | } |
793 | } |
794 | |
795 | static void |
796 | remove_step_breakpoint () |
797 | { |
798 | if (step_resume_break_address && !step_resume_break_duplicate) |
799 | write_memory (step_resume_break_address, step_resume_break_shadow, |
800 | sizeof break_insn); |
801 | } |
802 | \f |
803 | /* Specify how various signals in the inferior should be handled. */ |
804 | |
805 | static void |
806 | handle_command (args, from_tty) |
807 | char *args; |
808 | int from_tty; |
809 | { |
810 | register char *p = args; |
811 | int signum; |
812 | register int digits, wordlen; |
813 | |
814 | if (!args) |
815 | error_no_arg ("signal to handle"); |
816 | |
817 | while (*p) |
818 | { |
819 | /* Find the end of the next word in the args. */ |
820 | for (wordlen = 0; p[wordlen] && p[wordlen] != ' ' && p[wordlen] != '\t'; |
821 | wordlen++); |
822 | for (digits = 0; p[digits] >= '0' && p[digits] <= '9'; digits++); |
823 | |
824 | /* If it is all digits, it is signal number to operate on. */ |
825 | if (digits == wordlen) |
826 | { |
827 | signum = atoi (p); |
828 | if (signum == SIGTRAP || signum == SIGINT) |
829 | { |
830 | if (!query ("Signal %d is used by the debugger.\nAre you sure you want to change it? ", signum)) |
831 | error ("Not confirmed."); |
832 | } |
833 | } |
834 | else if (signum == 0) |
835 | error ("First argument is not a signal number."); |
836 | |
837 | /* Else, if already got a signal number, look for flag words |
838 | saying what to do for it. */ |
839 | else if (!strncmp (p, "stop", wordlen)) |
840 | { |
841 | signal_stop[signum] = 1; |
842 | signal_print[signum] = 1; |
843 | } |
844 | else if (wordlen >= 2 && !strncmp (p, "print", wordlen)) |
845 | signal_print[signum] = 1; |
846 | else if (wordlen >= 2 && !strncmp (p, "pass", wordlen)) |
847 | signal_program[signum] = 1; |
848 | else if (!strncmp (p, "ignore", wordlen)) |
849 | signal_program[signum] = 0; |
850 | else if (wordlen >= 3 && !strncmp (p, "nostop", wordlen)) |
851 | signal_stop[signum] = 0; |
852 | else if (wordlen >= 4 && !strncmp (p, "noprint", wordlen)) |
853 | { |
854 | signal_print[signum] = 0; |
855 | signal_stop[signum] = 0; |
856 | } |
857 | else if (wordlen >= 4 && !strncmp (p, "nopass", wordlen)) |
858 | signal_program[signum] = 0; |
859 | else if (wordlen >= 3 && !strncmp (p, "noignore", wordlen)) |
860 | signal_program[signum] = 1; |
861 | /* Not a number and not a recognized flag word => complain. */ |
862 | else |
863 | { |
864 | p[wordlen] = 0; |
865 | error ("Unrecognized flag word: \"%s\".", p); |
866 | } |
867 | |
868 | /* Find start of next word. */ |
869 | p += wordlen; |
870 | while (*p == ' ' || *p == '\t') p++; |
871 | } |
872 | |
873 | if (from_tty) |
874 | { |
875 | /* Show the results. */ |
876 | printf ("Number\tStop\tPrint\tPass to program\tDescription\n"); |
877 | printf ("%d\t", signum); |
878 | printf ("%s\t", signal_stop[signum] ? "Yes" : "No"); |
879 | printf ("%s\t", signal_print[signum] ? "Yes" : "No"); |
880 | printf ("%s\t\t", signal_program[signum] ? "Yes" : "No"); |
881 | printf ("%s\n", sys_siglist[signum]); |
882 | } |
883 | } |
884 | |
885 | /* Print current contents of the tables set by the handle command. */ |
886 | |
887 | static void |
888 | signals_info (signum_exp) |
889 | char *signum_exp; |
890 | { |
891 | register int i; |
892 | printf ("Number\tStop\tPrint\tPass to program\tDescription\n"); |
893 | |
894 | if (signum_exp) |
895 | { |
896 | i = parse_and_eval_address (signum_exp); |
897 | printf ("%d\t", i); |
898 | printf ("%s\t", signal_stop[i] ? "Yes" : "No"); |
899 | printf ("%s\t", signal_print[i] ? "Yes" : "No"); |
900 | printf ("%s\t\t", signal_program[i] ? "Yes" : "No"); |
901 | printf ("%s\n", sys_siglist[i]); |
902 | return; |
903 | } |
904 | |
905 | printf ("\n"); |
906 | for (i = 0; i < NSIG; i++) |
907 | { |
908 | QUIT; |
909 | if (i > 0 && i % 16 == 0) |
910 | { |
911 | printf ("[Type Return to see more]"); |
912 | fflush (stdout); |
913 | read_line (); |
914 | } |
915 | printf ("%d\t", i); |
916 | printf ("%s\t", signal_stop[i] ? "Yes" : "No"); |
917 | printf ("%s\t", signal_print[i] ? "Yes" : "No"); |
918 | printf ("%s\t\t", signal_program[i] ? "Yes" : "No"); |
919 | printf ("%s\n", sys_siglist[i]); |
920 | } |
921 | |
922 | printf ("\nUse the \"handle\" command to change these tables.\n"); |
923 | } |
924 | \f |
925 | static |
926 | initialize () |
927 | { |
928 | register int i; |
929 | |
930 | add_info ("signals", signals_info, |
931 | "What debugger does when program gets various signals.\n\ |
932 | Specify a signal number as argument to print info on that signal only."); |
933 | |
934 | add_com ("handle", class_run, handle_command, |
935 | "Specify how to handle a signal.\n\ |
936 | Args are signal number followed by flags.\n\ |
937 | Flags allowed are \"stop\", \"print\", \"pass\",\n\ |
938 | \"nostop\", \"noprint\" or \"nopass\".\n\ |
939 | Print means print a message if this signal happens.\n\ |
940 | Stop means reenter debugger if this signal happens (implies print).\n\ |
941 | Pass means let program see this signal; otherwise program doesn't know.\n\ |
942 | Pass and Stop may be combined."); |
943 | |
944 | for (i = 0; i < NSIG; i++) |
945 | { |
946 | signal_stop[i] = 1; |
947 | signal_print[i] = 1; |
948 | signal_program[i] = 1; |
949 | } |
950 | |
951 | /* Signals caused by debugger's own actions |
952 | should not be given to the program afterwards. */ |
953 | signal_program[SIGTRAP] = 0; |
954 | signal_program[SIGINT] = 0; |
955 | |
956 | /* Signals that are not errors should not normally enter the debugger. */ |
957 | #ifdef SIGALRM |
958 | signal_stop[SIGALRM] = 0; |
959 | signal_print[SIGALRM] = 0; |
960 | #endif /* SIGALRM */ |
961 | #ifdef SIGVTALRM |
962 | signal_stop[SIGVTALRM] = 0; |
963 | signal_print[SIGVTALRM] = 0; |
964 | #endif /* SIGVTALRM */ |
965 | #ifdef SIGPROF |
966 | signal_stop[SIGPROF] = 0; |
967 | signal_print[SIGPROF] = 0; |
968 | #endif /* SIGPROF */ |
969 | #ifdef SIGCHLD |
970 | signal_stop[SIGCHLD] = 0; |
971 | signal_print[SIGCHLD] = 0; |
972 | #endif /* SIGCHLD */ |
973 | #ifdef SIGCLD |
974 | signal_stop[SIGCLD] = 0; |
975 | signal_print[SIGCLD] = 0; |
976 | #endif /* SIGCLD */ |
977 | #ifdef SIGIO |
978 | signal_stop[SIGIO] = 0; |
979 | signal_print[SIGIO] = 0; |
980 | #endif /* SIGIO */ |
981 | #ifdef SIGURG |
982 | signal_stop[SIGURG] = 0; |
983 | signal_print[SIGURG] = 0; |
984 | #endif /* SIGURG */ |
985 | } |
986 | |
987 | END_FILE |