1 /* Target-struct-independent code to start (run) and stop an inferior process.
2 Copyright 1986, 1987, 1988, 1989, 1991, 1992, 1993
3 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
21 /* Notes on the algorithm used in wait_for_inferior to determine if we
22 just did a subroutine call when stepping. We have the following
23 information at that point:
25 Current and previous (just before this step) pc.
26 Current and previous sp.
27 Current and previous start of current function.
29 If the starts of the functions don't match, then
31 a) We did a subroutine call.
33 In this case, the pc will be at the beginning of a function.
35 b) We did a subroutine return.
41 If we did a longjump, we were doing "nexti", since a next would
42 have attempted to skip over the assembly language routine in which
43 the longjmp is coded and would have simply been the equivalent of a
44 continue. I consider this ok behaivior. We'd like one of two
45 things to happen if we are doing a nexti through the longjmp()
46 routine: 1) It behaves as a stepi, or 2) It acts like a continue as
47 above. Given that this is a special case, and that anybody who
48 thinks that the concept of sub calls is meaningful in the context
49 of a longjmp, I'll take either one. Let's see what happens.
51 Acts like a subroutine return. I can handle that with no problem
54 -->So: If the current and previous beginnings of the current
55 function don't match, *and* the pc is at the start of a function,
56 we've done a subroutine call. If the pc is not at the start of a
57 function, we *didn't* do a subroutine call.
59 -->If the beginnings of the current and previous function do match,
62 a) We just did a recursive call.
64 In this case, we would be at the very beginning of a
65 function and 1) it will have a prologue (don't jump to
66 before prologue, or 2) (we assume here that it doesn't have
67 a prologue) there will have been a change in the stack
68 pointer over the last instruction. (Ie. it's got to put
69 the saved pc somewhere. The stack is the usual place. In
70 a recursive call a register is only an option if there's a
71 prologue to do something with it. This is even true on
72 register window machines; the prologue sets up the new
73 window. It might not be true on a register window machine
74 where the call instruction moved the register window
75 itself. Hmmm. One would hope that the stack pointer would
76 also change. If it doesn't, somebody send me a note, and
77 I'll work out a more general theory.
78 bug-gdb@prep.ai.mit.edu). This is true (albeit slipperly
79 so) on all machines I'm aware of:
81 m68k: Call changes stack pointer. Regular jumps don't.
83 sparc: Recursive calls must have frames and therefor,
86 vax: All calls have frames and hence change the
89 b) We did a return from a recursive call. I don't see that we
90 have either the ability or the need to distinguish this
91 from an ordinary jump. The stack frame will be printed
92 when and if the frame pointer changes; if we are in a
93 function without a frame pointer, it's the users own
96 c) We did a jump within a function. We assume that this is
97 true if we didn't do a recursive call.
99 d) We are in no-man's land ("I see no symbols here"). We
100 don't worry about this; it will make calls look like simple
101 jumps (and the stack frames will be printed when the frame
102 pointer moves), which is a reasonably non-violent response.
110 #include "inferior.h"
111 #include "breakpoint.h"
119 /* unistd.h is needed to #define X_OK */
123 #include <sys/file.h>
126 /* Prototypes for local functions */
129 signals_info PARAMS ((char *, int));
132 handle_command PARAMS ((char *, int));
135 sig_print_info PARAMS ((int));
138 sig_print_header PARAMS ((void));
141 remove_step_breakpoint PARAMS ((void));
144 insert_step_breakpoint PARAMS ((void));
147 resume_cleanups PARAMS ((int));
150 hook_stop_stub PARAMS ((char *));
152 /* GET_LONGJMP_TARGET returns the PC at which longjmp() will resume the
153 program. It needs to examine the jmp_buf argument and extract the PC
154 from it. The return value is non-zero on success, zero otherwise. */
155 #ifndef GET_LONGJMP_TARGET
156 #define GET_LONGJMP_TARGET(PC_ADDR) 0
160 /* Some machines have trampoline code that sits between function callers
161 and the actual functions themselves. If this machine doesn't have
162 such things, disable their processing. */
163 #ifndef SKIP_TRAMPOLINE_CODE
164 #define SKIP_TRAMPOLINE_CODE(pc) 0
167 /* For SVR4 shared libraries, each call goes through a small piece of
168 trampoline code in the ".init" section. IN_SOLIB_TRAMPOLINE evaluates
169 to nonzero if we are current stopped in one of these. */
170 #ifndef IN_SOLIB_TRAMPOLINE
171 #define IN_SOLIB_TRAMPOLINE(pc,name) 0
174 /* On some systems, the PC may be left pointing at an instruction that won't
175 actually be executed. This is usually indicated by a bit in the PSW. If
176 we find ourselves in such a state, then we step the target beyond the
177 nullified instruction before returning control to the user so as to avoid
180 #ifndef INSTRUCTION_NULLIFIED
181 #define INSTRUCTION_NULLIFIED 0
186 int safe_to_init_tdesc_context = 0;
187 extern dc_dcontext_t current_context;
190 /* Tables of how to react to signals; the user sets them. */
192 static unsigned char *signal_stop;
193 static unsigned char *signal_print;
194 static unsigned char *signal_program;
196 #define SET_SIGS(nsigs,sigs,flags) \
198 int signum = (nsigs); \
199 while (signum-- > 0) \
200 if ((sigs)[signum]) \
201 (flags)[signum] = 1; \
204 #define UNSET_SIGS(nsigs,sigs,flags) \
206 int signum = (nsigs); \
207 while (signum-- > 0) \
208 if ((sigs)[signum]) \
209 (flags)[signum] = 0; \
213 /* Command list pointer for the "stop" placeholder. */
215 static struct cmd_list_element *stop_command;
217 /* Nonzero if breakpoints are now inserted in the inferior. */
219 static int breakpoints_inserted;
221 /* Function inferior was in as of last step command. */
223 static struct symbol *step_start_function;
225 /* Nonzero => address for special breakpoint for resuming stepping. */
227 static CORE_ADDR step_resume_break_address;
229 /* Pointer to orig contents of the byte where the special breakpoint is. */
231 static char step_resume_break_shadow[BREAKPOINT_MAX];
233 /* Nonzero means the special breakpoint is a duplicate
234 so it has not itself been inserted. */
236 static int step_resume_break_duplicate;
238 /* Nonzero if we are expecting a trace trap and should proceed from it. */
240 static int trap_expected;
242 /* Nonzero if the next time we try to continue the inferior, it will
243 step one instruction and generate a spurious trace trap.
244 This is used to compensate for a bug in HP-UX. */
246 static int trap_expected_after_continue;
248 /* Nonzero means expecting a trace trap
249 and should stop the inferior and return silently when it happens. */
253 /* Nonzero means expecting a trap and caller will handle it themselves.
254 It is used after attach, due to attaching to a process;
255 when running in the shell before the child program has been exec'd;
256 and when running some kinds of remote stuff (FIXME?). */
258 int stop_soon_quietly;
260 /* Nonzero if pc has been changed by the debugger
261 since the inferior stopped. */
265 /* Nonzero if proceed is being used for a "finish" command or a similar
266 situation when stop_registers should be saved. */
268 int proceed_to_finish;
270 /* Save register contents here when about to pop a stack dummy frame,
271 if-and-only-if proceed_to_finish is set.
272 Thus this contains the return value from the called function (assuming
273 values are returned in a register). */
275 char stop_registers[REGISTER_BYTES];
277 /* Nonzero if program stopped due to error trying to insert breakpoints. */
279 static int breakpoints_failed;
281 /* Nonzero after stop if current stack frame should be printed. */
283 static int stop_print_frame;
285 #ifdef NO_SINGLE_STEP
286 extern int one_stepped; /* From machine dependent code */
287 extern void single_step (); /* Same. */
288 #endif /* NO_SINGLE_STEP */
291 /* Things to clean up if we QUIT out of resume (). */
294 resume_cleanups (arg)
300 /* Resume the inferior, but allow a QUIT. This is useful if the user
301 wants to interrupt some lengthy single-stepping operation
302 (for child processes, the SIGINT goes to the inferior, and so
303 we get a SIGINT random_signal, but for remote debugging and perhaps
304 other targets, that's not true).
306 STEP nonzero if we should step (zero to continue instead).
307 SIG is the signal to give the inferior (zero for none). */
313 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
316 #ifdef NO_SINGLE_STEP
318 single_step(sig); /* Do it the hard way, w/temp breakpoints */
319 step = 0; /* ...and don't ask hardware to do it. */
323 /* Handle any optimized stores to the inferior NOW... */
324 #ifdef DO_DEFERRED_STORES
328 target_resume (step, sig);
329 discard_cleanups (old_cleanups);
333 /* Clear out all variables saying what to do when inferior is continued.
334 First do this, then set the ones you want, then call `proceed'. */
337 clear_proceed_status ()
340 step_range_start = 0;
342 step_frame_address = 0;
343 step_over_calls = -1;
344 step_resume_break_address = 0;
346 stop_soon_quietly = 0;
347 proceed_to_finish = 0;
348 breakpoint_proceeded = 1; /* We're about to proceed... */
350 /* Discard any remaining commands or status from previous stop. */
351 bpstat_clear (&stop_bpstat);
354 /* Basic routine for continuing the program in various fashions.
356 ADDR is the address to resume at, or -1 for resume where stopped.
357 SIGGNAL is the signal to give it, or 0 for none,
358 or -1 for act according to how it stopped.
359 STEP is nonzero if should trap after one instruction.
360 -1 means return after that and print nothing.
361 You should probably set various step_... variables
362 before calling here, if you are stepping.
364 You should call clear_proceed_status before calling proceed. */
367 proceed (addr, siggnal, step)
375 step_start_function = find_pc_function (read_pc ());
379 if (addr == (CORE_ADDR)-1)
381 /* If there is a breakpoint at the address we will resume at,
382 step one instruction before inserting breakpoints
383 so that we do not stop right away. */
385 if (!pc_changed && breakpoint_here_p (read_pc ()))
391 if (trap_expected_after_continue)
393 /* If (step == 0), a trap will be automatically generated after
394 the first instruction is executed. Force step one
395 instruction to clear this condition. This should not occur
396 if step is nonzero, but it is harmless in that case. */
398 trap_expected_after_continue = 0;
402 /* We will get a trace trap after one instruction.
403 Continue it automatically and insert breakpoints then. */
407 int temp = insert_breakpoints ();
410 print_sys_errmsg ("ptrace", temp);
411 error ("Cannot insert breakpoints.\n\
412 The same program may be running in another process.");
414 breakpoints_inserted = 1;
417 /* Install inferior's terminal modes. */
418 target_terminal_inferior ();
421 stop_signal = siggnal;
422 /* If this signal should not be seen by program,
423 give it zero. Used for debugging signals. */
424 else if (stop_signal < NSIG && !signal_program[stop_signal])
427 /* Resume inferior. */
428 resume (oneproc || step || bpstat_should_step (), stop_signal);
430 /* Wait for it to stop (if not standalone)
431 and in any case decode why it stopped, and act accordingly. */
433 wait_for_inferior ();
437 /* Record the pc and sp of the program the last time it stopped.
438 These are just used internally by wait_for_inferior, but need
439 to be preserved over calls to it and cleared when the inferior
441 static CORE_ADDR prev_pc;
442 static CORE_ADDR prev_sp;
443 static CORE_ADDR prev_func_start;
444 static char *prev_func_name;
447 /* Start remote-debugging of a machine over a serial link. */
452 init_wait_for_inferior ();
453 clear_proceed_status ();
454 stop_soon_quietly = 1;
456 wait_for_inferior ();
460 /* Initialize static vars when a new inferior begins. */
463 init_wait_for_inferior ()
465 /* These are meaningless until the first time through wait_for_inferior. */
469 prev_func_name = NULL;
471 trap_expected_after_continue = 0;
472 breakpoints_inserted = 0;
473 mark_breakpoints_out ();
474 stop_signal = 0; /* Don't confuse first call to proceed(). */
479 /* Wait for control to return from inferior to debugger.
480 If inferior gets a signal, we may decide to start it up again
481 instead of returning. That is why there is a loop in this function.
482 When this function actually returns it means the inferior
483 should be left stopped and GDB should read more commands. */
492 CORE_ADDR stop_func_start;
493 char *stop_func_name;
494 CORE_ADDR prologue_pc, tmp;
495 int stop_step_resume_break;
496 struct symtab_and_line sal;
497 int remove_breakpoints_on_following_step = 0;
499 int handling_longjmp = 0; /* FIXME */
500 struct symtab *symtab;
502 sal = find_pc_line(prev_pc, 0);
503 current_line = sal.line;
507 /* Clean up saved state that will become invalid. */
509 flush_cached_frames ();
510 registers_changed ();
514 #ifdef SIGTRAP_STOP_AFTER_LOAD
516 /* Somebody called load(2), and it gave us a "trap signal after load".
517 Ignore it gracefully. */
519 SIGTRAP_STOP_AFTER_LOAD (w);
522 /* See if the process still exists; clean up if it doesn't. */
525 target_terminal_ours (); /* Must do this before mourn anyway */
527 printf_filtered ("\nProgram exited with code 0%o.\n",
528 (unsigned int)WEXITSTATUS (w));
531 printf_filtered ("\nProgram exited normally.\n");
533 target_mourn_inferior ();
534 #ifdef NO_SINGLE_STEP
537 stop_print_frame = 0;
540 else if (!WIFSTOPPED (w))
542 stop_print_frame = 0;
543 stop_signal = WTERMSIG (w);
544 target_terminal_ours (); /* Must do this before mourn anyway */
545 target_kill (); /* kill mourns as well */
546 #ifdef PRINT_RANDOM_SIGNAL
547 printf_filtered ("\nProgram terminated: ");
548 PRINT_RANDOM_SIGNAL (stop_signal);
550 printf_filtered ("\nProgram terminated with signal %d, %s\n",
551 stop_signal, safe_strsignal (stop_signal));
553 printf_filtered ("The inferior process no longer exists.\n");
555 #ifdef NO_SINGLE_STEP
561 #ifdef NO_SINGLE_STEP
563 single_step (0); /* This actually cleans up the ss */
564 #endif /* NO_SINGLE_STEP */
566 /* If PC is pointing at a nullified instruction, then step beyond it so that
567 the user won't be confused when GDB appears to be ready to execute it. */
569 if (INSTRUCTION_NULLIFIED)
575 stop_pc = read_pc ();
576 set_current_frame ( create_new_frame (read_register (FP_REGNUM),
579 stop_frame_address = FRAME_FP (get_current_frame ());
580 stop_sp = read_register (SP_REGNUM);
581 /* XXX - FIXME. Need to figure out a better way to grab the stack seg reg. */
582 #ifdef GDB_TARGET_IS_H8500
583 stop_sp |= read_register (SEG_T_REGNUM) << 16;
587 /* Don't care about return value; stop_func_start and stop_func_name
588 will both be 0 if it doesn't work. */
589 find_pc_partial_function (stop_pc, &stop_func_name, &stop_func_start);
590 stop_func_start += FUNCTION_START_OFFSET;
592 bpstat_clear (&stop_bpstat);
594 stop_stack_dummy = 0;
595 stop_print_frame = 1;
596 stop_step_resume_break = 0;
598 stopped_by_random_signal = 0;
599 breakpoints_failed = 0;
601 /* Look at the cause of the stop, and decide what to do.
602 The alternatives are:
603 1) break; to really stop and return to the debugger,
604 2) drop through to start up again
605 (set another_trap to 1 to single step once)
606 3) set random_signal to 1, and the decision between 1 and 2
607 will be made according to the signal handling tables. */
609 stop_signal = WSTOPSIG (w);
611 /* First, distinguish signals caused by the debugger from signals
612 that have to do with the program's own actions.
613 Note that breakpoint insns may cause SIGTRAP or SIGILL
614 or SIGEMT, depending on the operating system version.
615 Here we detect when a SIGILL or SIGEMT is really a breakpoint
616 and change it to SIGTRAP. */
618 if (stop_signal == SIGTRAP
619 || (breakpoints_inserted &&
620 (stop_signal == SIGILL
622 || stop_signal == SIGEMT
625 || stop_soon_quietly)
627 if (stop_signal == SIGTRAP && stop_after_trap)
629 stop_print_frame = 0;
632 if (stop_soon_quietly)
635 /* Don't even think about breakpoints
636 if just proceeded over a breakpoint.
638 However, if we are trying to proceed over a breakpoint
639 and end up in sigtramp, then step_resume_break_address
640 will be set and we should check whether we've hit the
642 if (stop_signal == SIGTRAP && trap_expected
643 && step_resume_break_address == 0)
644 bpstat_clear (&stop_bpstat);
647 /* See if there is a breakpoint at the current PC. */
648 #if DECR_PC_AFTER_BREAK
649 /* Notice the case of stepping through a jump
650 that lands just after a breakpoint.
651 Don't confuse that with hitting the breakpoint.
652 What we check for is that 1) stepping is going on
653 and 2) the pc before the last insn does not match
654 the address of the breakpoint before the current pc. */
655 if (prev_pc == stop_pc - DECR_PC_AFTER_BREAK
657 || step_resume_break_address
658 || handling_longjmp /* FIXME */)
659 #endif /* DECR_PC_AFTER_BREAK not zero */
661 /* See if we stopped at the special breakpoint for
662 stepping over a subroutine call. If both are zero,
663 this wasn't the reason for the stop. */
664 if (step_resume_break_address
665 && stop_pc - DECR_PC_AFTER_BREAK
666 == step_resume_break_address)
668 stop_step_resume_break = 1;
669 if (DECR_PC_AFTER_BREAK)
671 stop_pc -= DECR_PC_AFTER_BREAK;
678 bpstat_stop_status (&stop_pc, stop_frame_address);
679 /* Following in case break condition called a
681 stop_print_frame = 1;
686 if (stop_signal == SIGTRAP)
688 = !(bpstat_explains_signal (stop_bpstat)
690 || stop_step_resume_break
691 || PC_IN_CALL_DUMMY (stop_pc, stop_sp, stop_frame_address)
692 || (step_range_end && !step_resume_break_address));
696 = !(bpstat_explains_signal (stop_bpstat)
697 || stop_step_resume_break
698 /* End of a stack dummy. Some systems (e.g. Sony
699 news) give another signal besides SIGTRAP,
700 so check here as well as above. */
701 || PC_IN_CALL_DUMMY (stop_pc, stop_sp, stop_frame_address)
704 stop_signal = SIGTRAP;
710 /* For the program's own signals, act according to
711 the signal handling tables. */
715 /* Signal not for debugging purposes. */
718 stopped_by_random_signal = 1;
720 if (stop_signal >= NSIG
721 || signal_print[stop_signal])
724 target_terminal_ours_for_output ();
725 #ifdef PRINT_RANDOM_SIGNAL
726 PRINT_RANDOM_SIGNAL (stop_signal);
728 printf_filtered ("\nProgram received signal %d, %s\n",
729 stop_signal, safe_strsignal (stop_signal));
730 #endif /* PRINT_RANDOM_SIGNAL */
733 if (stop_signal >= NSIG
734 || signal_stop[stop_signal])
736 /* If not going to stop, give terminal back
737 if we took it away. */
739 target_terminal_inferior ();
741 /* Clear the signal if it should not be passed. */
742 if (signal_program[stop_signal] == 0)
745 /* Note that virtually all the code below does `if !random_signal'.
746 Perhaps this code should end with a goto or continue. At least
747 one (now fixed) bug was caused by this -- a !random_signal was
748 missing in one of the tests below. */
751 /* Handle cases caused by hitting a breakpoint. */
755 CORE_ADDR jmp_buf_pc;
756 enum bpstat_what what = bpstat_what (stop_bpstat);
760 case BPSTAT_WHAT_SET_LONGJMP_RESUME:
761 /* If we hit the breakpoint at longjmp, disable it for the
762 duration of this command. Then, install a temporary
763 breakpoint at the target of the jmp_buf. */
764 disable_longjmp_breakpoint();
765 remove_breakpoints ();
766 breakpoints_inserted = 0;
767 if (!GET_LONGJMP_TARGET(&jmp_buf_pc)) goto keep_going;
769 /* Need to blow away step-resume breakpoint, as it
770 interferes with us */
771 remove_step_breakpoint ();
772 step_resume_break_address = 0;
773 stop_step_resume_break = 0;
776 /* FIXME - Need to implement nested temporary breakpoints */
777 if (step_over_calls > 0)
778 set_longjmp_resume_breakpoint(jmp_buf_pc,
779 get_current_frame());
782 set_longjmp_resume_breakpoint(jmp_buf_pc, NULL);
783 handling_longjmp = 1; /* FIXME */
786 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
787 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE:
788 remove_breakpoints ();
789 breakpoints_inserted = 0;
791 /* FIXME - Need to implement nested temporary breakpoints */
793 && (stop_frame_address
794 INNER_THAN step_frame_address))
800 disable_longjmp_breakpoint();
801 handling_longjmp = 0; /* FIXME */
802 if (what == BPSTAT_WHAT_CLEAR_LONGJMP_RESUME)
804 /* else fallthrough */
806 case BPSTAT_WHAT_SINGLE:
807 if (breakpoints_inserted)
808 remove_breakpoints ();
809 remove_step_breakpoint ();
810 breakpoints_inserted = 0;
812 /* Still need to check other stuff, at least the case
813 where we are stepping and step out of the right range. */
816 case BPSTAT_WHAT_STOP_NOISY:
817 stop_print_frame = 1;
820 case BPSTAT_WHAT_STOP_SILENT:
821 stop_print_frame = 0;
824 case BPSTAT_WHAT_KEEP_CHECKING:
828 if (stop_step_resume_break)
830 /* But if we have hit the step-resumption breakpoint,
831 remove it. It has done its job getting us here.
832 The sp test is to make sure that we don't get hung
833 up in recursive calls in functions without frame
834 pointers. If the stack pointer isn't outside of
835 where the breakpoint was set (within a routine to be
836 stepped over), we're in the middle of a recursive
837 call. Not true for reg window machines (sparc)
838 because the must change frames to call things and
839 the stack pointer doesn't have to change if it
840 the bp was set in a routine without a frame (pc can
841 be stored in some other window).
843 The removal of the sp test is to allow calls to
844 alloca. Nasty things were happening. Oh, well,
845 gdb can only handle one level deep of lack of
849 Disable test for step_frame_address match so that we always stop even if the
850 frames don't match. Reason: if we hit the step_resume_breakpoint, there is
851 no way to temporarily disable it so that we can step past it. If we leave
852 the breakpoint in, then we loop forever repeatedly hitting, but never
853 getting past the breakpoint. This change keeps nexting over recursive
854 function calls from hanging gdb.
857 if (* step_frame_address == 0
858 || (step_frame_address == stop_frame_address))
861 remove_step_breakpoint ();
862 step_resume_break_address = 0;
864 /* If were waiting for a trap, hitting the step_resume_break
865 doesn't count as getting it. */
872 /* We come here if we hit a breakpoint but should not
873 stop for it. Possibly we also were stepping
874 and should stop for that. So fall through and
875 test for stepping. But, if not stepping,
878 /* If this is the breakpoint at the end of a stack dummy,
879 just stop silently. */
881 && PC_IN_CALL_DUMMY (stop_pc, stop_sp, stop_frame_address))
883 stop_print_frame = 0;
884 stop_stack_dummy = 1;
886 trap_expected_after_continue = 1;
891 if (step_resume_break_address)
892 /* Having a step-resume breakpoint overrides anything
893 else having to do with stepping commands until
894 that breakpoint is reached. */
896 /* If stepping through a line, keep going if still within it. */
897 else if (!random_signal
899 && stop_pc >= step_range_start
900 && stop_pc < step_range_end
901 /* The step range might include the start of the
902 function, so if we are at the start of the
903 step range and either the stack or frame pointers
904 just changed, we've stepped outside */
905 && !(stop_pc == step_range_start
906 && stop_frame_address
907 && (stop_sp INNER_THAN prev_sp
908 || stop_frame_address != step_frame_address)))
913 /* We stepped out of the stepping range. See if that was due
914 to a subroutine call that we should proceed to the end of. */
915 else if (!random_signal && step_range_end)
917 /* Did we just take a signal? */
918 if (IN_SIGTRAMP (stop_pc, stop_func_name)
919 && !IN_SIGTRAMP (prev_pc, prev_func_name))
921 /* This code is needed at least in the following case:
922 The user types "next" and then a signal arrives (before
923 the "next" is done). */
924 /* We've just taken a signal; go until we are back to
925 the point where we took it and one more. */
926 step_resume_break_address = prev_pc;
927 step_resume_break_duplicate =
928 breakpoint_here_p (step_resume_break_address);
929 if (breakpoints_inserted)
930 insert_step_breakpoint ();
931 /* Make sure that the stepping range gets us past
933 if (step_range_end == 1)
934 step_range_end = (step_range_start = prev_pc) + 1;
935 remove_breakpoints_on_following_step = 1;
941 /* Do this after the IN_SIGTRAMP check; it might give
943 prologue_pc = stop_func_start;
944 SKIP_PROLOGUE (prologue_pc);
947 /* ==> See comments at top of file on this algorithm. <==*/
949 if ((stop_pc == stop_func_start
950 || IN_SOLIB_TRAMPOLINE (stop_pc, stop_func_name))
951 && (stop_func_start != prev_func_start
952 || prologue_pc != stop_func_start
953 || stop_sp != prev_sp))
955 /* It's a subroutine call.
956 (0) If we are not stepping over any calls ("stepi"), we
958 (1) If we're doing a "next", we want to continue through
959 the call ("step over the call").
960 (2) If we are in a function-call trampoline (a stub between
961 the calling routine and the real function), locate
962 the real function and change stop_func_start.
963 (3) If we're doing a "step", and there are no debug symbols
964 at the target of the call, we want to continue through
965 it ("step over the call").
966 (4) Otherwise, we want to stop soon, after the function
967 prologue ("step into the call"). */
969 if (step_over_calls == 0)
971 /* I presume that step_over_calls is only 0 when we're
972 supposed to be stepping at the assembly language level. */
977 if (step_over_calls > 0)
978 goto step_over_function;
980 tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
982 stop_func_start = tmp;
984 symtab = find_pc_symtab (stop_func_start);
985 if (symtab && LINETABLE (symtab))
986 goto step_into_function;
989 /* A subroutine call has happened. */
990 /* Set a special breakpoint after the return */
991 step_resume_break_address =
993 (SAVED_PC_AFTER_CALL (get_current_frame ()));
994 step_resume_break_duplicate
995 = breakpoint_here_p (step_resume_break_address);
996 if (breakpoints_inserted)
997 insert_step_breakpoint ();
1001 /* Subroutine call with source code we should not step over.
1002 Do step to the first line of code in it. */
1003 SKIP_PROLOGUE (stop_func_start);
1004 sal = find_pc_line (stop_func_start, 0);
1005 /* Use the step_resume_break to step until
1006 the end of the prologue, even if that involves jumps
1007 (as it seems to on the vax under 4.2). */
1008 /* If the prologue ends in the middle of a source line,
1009 continue to the end of that source line.
1010 Otherwise, just go to end of prologue. */
1011 #ifdef PROLOGUE_FIRSTLINE_OVERLAP
1012 /* no, don't either. It skips any code that's
1013 legitimately on the first line. */
1015 if (sal.end && sal.pc != stop_func_start)
1016 stop_func_start = sal.end;
1019 if (stop_func_start == stop_pc)
1021 /* We are already there: stop now. */
1026 /* Put the step-breakpoint there and go until there. */
1028 step_resume_break_address = stop_func_start;
1030 step_resume_break_duplicate
1031 = breakpoint_here_p (step_resume_break_address);
1032 if (breakpoints_inserted)
1033 insert_step_breakpoint ();
1034 /* Do not specify what the fp should be when we stop
1035 since on some machines the prologue
1036 is where the new fp value is established. */
1037 step_frame_address = 0;
1038 /* And make sure stepping stops right away then. */
1039 step_range_end = step_range_start;
1044 /* We've wandered out of the step range (but haven't done a
1045 subroutine call or return). */
1047 sal = find_pc_line(stop_pc, 0);
1049 if (step_range_end == 1 || /* stepi or nexti */
1050 sal.line == 0 || /* ...or no line # info */
1051 (stop_pc == sal.pc /* ...or we're at the start */
1052 && current_line != sal.line)) { /* of a different line */
1053 /* Stop because we're done stepping. */
1057 /* We aren't done stepping, and we have line number info for $pc.
1058 Optimize by setting the step_range for the line.
1059 (We might not be in the original line, but if we entered a
1060 new line in mid-statement, we continue stepping. This makes
1061 things like for(;;) statements work better.) */
1062 step_range_start = sal.pc;
1063 step_range_end = sal.end;
1066 /* We never fall through here */
1070 && IN_SIGTRAMP (stop_pc, stop_func_name)
1071 && !IN_SIGTRAMP (prev_pc, prev_func_name))
1073 /* What has happened here is that we have just stepped the inferior
1074 with a signal (because it is a signal which shouldn't make
1075 us stop), thus stepping into sigtramp.
1077 So we need to set a step_resume_break_address breakpoint
1078 and continue until we hit it, and then step. */
1079 step_resume_break_address = prev_pc;
1080 /* Always 1, I think, but it's probably easier to have
1081 the step_resume_break as usual rather than trying to
1082 re-use the breakpoint which is already there. */
1083 step_resume_break_duplicate =
1084 breakpoint_here_p (step_resume_break_address);
1085 if (breakpoints_inserted)
1086 insert_step_breakpoint ();
1087 remove_breakpoints_on_following_step = 1;
1091 /* My apologies to the gods of structured programming. */
1092 /* Come to this label when you need to resume the inferior. It's really much
1093 cleaner at this time to do a goto than to try and figure out what the
1094 if-else chain ought to look like!! */
1099 /* Save the pc before execution, to compare with pc after stop. */
1100 prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */
1101 prev_func_start = stop_func_start; /* Ok, since if DECR_PC_AFTER
1102 BREAK is defined, the
1103 original pc would not have
1104 been at the start of a
1106 prev_func_name = stop_func_name;
1109 /* If we did not do break;, it means we should keep
1110 running the inferior and not return to debugger. */
1112 if (trap_expected && stop_signal != SIGTRAP)
1114 /* We took a signal (which we are supposed to pass through to
1115 the inferior, else we'd have done a break above) and we
1116 haven't yet gotten our trap. Simply continue. */
1117 resume ((step_range_end && !step_resume_break_address)
1118 || (trap_expected && !step_resume_break_address)
1119 || bpstat_should_step (),
1124 /* Either the trap was not expected, but we are continuing
1125 anyway (the user asked that this signal be passed to the
1128 The signal was SIGTRAP, e.g. it was our signal, but we
1129 decided we should resume from it.
1131 We're going to run this baby now!
1133 Insert breakpoints now, unless we are trying
1134 to one-proceed past a breakpoint. */
1135 /* If we've just finished a special step resume and we don't
1136 want to hit a breakpoint, pull em out. */
1137 if (!step_resume_break_address &&
1138 remove_breakpoints_on_following_step)
1140 remove_breakpoints_on_following_step = 0;
1141 remove_breakpoints ();
1142 breakpoints_inserted = 0;
1144 else if (!breakpoints_inserted &&
1145 (step_resume_break_address != 0 || !another_trap))
1147 insert_step_breakpoint ();
1148 breakpoints_failed = insert_breakpoints ();
1149 if (breakpoints_failed)
1151 breakpoints_inserted = 1;
1154 trap_expected = another_trap;
1156 if (stop_signal == SIGTRAP)
1159 #ifdef SHIFT_INST_REGS
1160 /* I'm not sure when this following segment applies. I do know, now,
1161 that we shouldn't rewrite the regs when we were stopped by a
1162 random signal from the inferior process. */
1164 if (!bpstat_explains_signal (stop_bpstat)
1165 && (stop_signal != SIGCLD)
1166 && !stopped_by_random_signal)
1168 CORE_ADDR pc_contents = read_register (PC_REGNUM);
1169 CORE_ADDR npc_contents = read_register (NPC_REGNUM);
1170 if (pc_contents != npc_contents)
1172 write_register (NNPC_REGNUM, npc_contents);
1173 write_register (NPC_REGNUM, pc_contents);
1176 #endif /* SHIFT_INST_REGS */
1178 resume ((!step_resume_break_address
1179 && !handling_longjmp
1182 || bpstat_should_step (),
1188 if (target_has_execution)
1190 /* Assuming the inferior still exists, set these up for next
1191 time, just like we did above if we didn't break out of the
1193 prev_pc = read_pc ();
1194 prev_func_start = stop_func_start;
1195 prev_func_name = stop_func_name;
1200 /* Here to return control to GDB when the inferior stops for real.
1201 Print appropriate messages, remove breakpoints, give terminal our modes.
1203 STOP_PRINT_FRAME nonzero means print the executing frame
1204 (pc, function, args, file, line number and line text).
1205 BREAKPOINTS_FAILED nonzero means stop was due to error
1206 attempting to insert breakpoints. */
1211 /* Make sure that the current_frame's pc is correct. This
1212 is a correction for setting up the frame info before doing
1213 DECR_PC_AFTER_BREAK */
1214 if (target_has_execution)
1215 (get_current_frame ())->pc = read_pc ();
1217 if (breakpoints_failed)
1219 target_terminal_ours_for_output ();
1220 print_sys_errmsg ("ptrace", breakpoints_failed);
1221 printf_filtered ("Stopped; cannot insert breakpoints.\n\
1222 The same program may be running in another process.\n");
1225 if (target_has_execution)
1226 remove_step_breakpoint ();
1228 if (target_has_execution && breakpoints_inserted)
1229 if (remove_breakpoints ())
1231 target_terminal_ours_for_output ();
1232 printf_filtered ("Cannot remove breakpoints because program is no longer writable.\n\
1233 It might be running in another process.\n\
1234 Further execution is probably impossible.\n");
1237 breakpoints_inserted = 0;
1239 /* Delete the breakpoint we stopped at, if it wants to be deleted.
1240 Delete any breakpoint that is to be deleted at the next stop. */
1242 breakpoint_auto_delete (stop_bpstat);
1244 /* If an auto-display called a function and that got a signal,
1245 delete that auto-display to avoid an infinite recursion. */
1247 if (stopped_by_random_signal)
1248 disable_current_display ();
1250 if (step_multi && stop_step)
1253 target_terminal_ours ();
1255 /* Look up the hook_stop and run it if it exists. */
1257 if (stop_command->hook)
1259 catch_errors (hook_stop_stub, (char *)stop_command->hook,
1260 "Error while running hook_stop:\n");
1263 if (!target_has_stack)
1266 /* Select innermost stack frame except on return from a stack dummy routine,
1267 or if the program has exited. Print it without a level number if
1268 we have changed functions or hit a breakpoint. Print source line
1270 if (!stop_stack_dummy)
1272 select_frame (get_current_frame (), 0);
1274 if (stop_print_frame)
1278 source_only = bpstat_print (stop_bpstat);
1279 source_only = source_only ||
1281 && step_frame_address == stop_frame_address
1282 && step_start_function == find_pc_function (stop_pc));
1284 print_stack_frame (selected_frame, -1, source_only? -1: 1);
1286 /* Display the auto-display expressions. */
1291 /* Save the function value return registers, if we care.
1292 We might be about to restore their previous contents. */
1293 if (proceed_to_finish)
1294 read_register_bytes (0, stop_registers, REGISTER_BYTES);
1296 if (stop_stack_dummy)
1298 /* Pop the empty frame that contains the stack dummy.
1299 POP_FRAME ends with a setting of the current frame, so we
1300 can use that next. */
1302 select_frame (get_current_frame (), 0);
1307 hook_stop_stub (cmd)
1310 execute_user_command ((struct cmd_list_element *)cmd, 0);
1316 insert_step_breakpoint ()
1318 if (step_resume_break_address && !step_resume_break_duplicate)
1319 target_insert_breakpoint (step_resume_break_address,
1320 step_resume_break_shadow);
1324 remove_step_breakpoint ()
1326 if (step_resume_break_address && !step_resume_break_duplicate)
1327 target_remove_breakpoint (step_resume_break_address,
1328 step_resume_break_shadow);
1331 int signal_stop_state (signo)
1334 return ((signo >= 0 && signo < NSIG) ? signal_stop[signo] : 0);
1337 int signal_print_state (signo)
1340 return ((signo >= 0 && signo < NSIG) ? signal_print[signo] : 0);
1343 int signal_pass_state (signo)
1346 return ((signo >= 0 && signo < NSIG) ? signal_program[signo] : 0);
1352 printf_filtered ("Signal\t\tStop\tPrint\tPass to program\tDescription\n");
1356 sig_print_info (number)
1361 if ((name = strsigno (number)) == NULL)
1362 printf_filtered ("%d\t\t", number);
1364 printf_filtered ("%s (%d)\t", name, number);
1365 printf_filtered ("%s\t", signal_stop[number] ? "Yes" : "No");
1366 printf_filtered ("%s\t", signal_print[number] ? "Yes" : "No");
1367 printf_filtered ("%s\t\t", signal_program[number] ? "Yes" : "No");
1368 printf_filtered ("%s\n", safe_strsignal (number));
1371 /* Specify how various signals in the inferior should be handled. */
1374 handle_command (args, from_tty)
1379 int digits, wordlen;
1380 int sigfirst, signum, siglast;
1383 unsigned char *sigs;
1384 struct cleanup *old_chain;
1388 error_no_arg ("signal to handle");
1391 /* Allocate and zero an array of flags for which signals to handle. */
1393 nsigs = signo_max () + 1;
1394 sigs = (unsigned char *) alloca (nsigs);
1395 memset (sigs, 0, nsigs);
1397 /* Break the command line up into args. */
1399 argv = buildargv (args);
1404 old_chain = make_cleanup (freeargv, (char *) argv);
1406 /* Walk through the args, looking for signal numbers, signal names, and
1407 actions. Signal numbers and signal names may be interspersed with
1408 actions, with the actions being performed for all signals cumulatively
1409 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
1411 while (*argv != NULL)
1413 wordlen = strlen (*argv);
1414 for (digits = 0; isdigit ((*argv)[digits]); digits++) {;}
1416 sigfirst = siglast = -1;
1418 if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
1420 /* Apply action to all signals except those used by the
1421 debugger. Silently skip those. */
1424 siglast = nsigs - 1;
1426 else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
1428 SET_SIGS (nsigs, sigs, signal_stop);
1429 SET_SIGS (nsigs, sigs, signal_print);
1431 else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
1433 UNSET_SIGS (nsigs, sigs, signal_program);
1435 else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
1437 SET_SIGS (nsigs, sigs, signal_print);
1439 else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
1441 SET_SIGS (nsigs, sigs, signal_program);
1443 else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
1445 UNSET_SIGS (nsigs, sigs, signal_stop);
1447 else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
1449 SET_SIGS (nsigs, sigs, signal_program);
1451 else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
1453 UNSET_SIGS (nsigs, sigs, signal_print);
1454 UNSET_SIGS (nsigs, sigs, signal_stop);
1456 else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
1458 UNSET_SIGS (nsigs, sigs, signal_program);
1460 else if (digits > 0)
1462 sigfirst = siglast = atoi (*argv);
1463 if ((*argv)[digits] == '-')
1465 siglast = atoi ((*argv) + digits + 1);
1467 if (sigfirst > siglast)
1469 /* Bet he didn't figure we'd think of this case... */
1474 if (sigfirst < 0 || sigfirst >= nsigs)
1476 error ("Signal %d not in range 0-%d", sigfirst, nsigs - 1);
1478 if (siglast < 0 || siglast >= nsigs)
1480 error ("Signal %d not in range 0-%d", siglast, nsigs - 1);
1483 else if ((signum = strtosigno (*argv)) != 0)
1485 sigfirst = siglast = signum;
1489 /* Not a number and not a recognized flag word => complain. */
1490 error ("Unrecognized or ambiguous flag word: \"%s\".", *argv);
1493 /* If any signal numbers or symbol names were found, set flags for
1494 which signals to apply actions to. */
1496 for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
1502 if (!allsigs && !sigs[signum])
1504 if (query ("%s is used by the debugger.\nAre you sure you want to change it? ", strsigno (signum)))
1510 printf ("Not confirmed, unchanged.\n");
1524 target_notice_signals();
1528 /* Show the results. */
1529 sig_print_header ();
1530 for (signum = 0; signum < nsigs; signum++)
1534 sig_print_info (signum);
1539 do_cleanups (old_chain);
1542 /* Print current contents of the tables set by the handle command. */
1545 signals_info (signum_exp, from_tty)
1550 sig_print_header ();
1554 /* First see if this is a symbol name. */
1555 i = strtosigno (signum_exp);
1558 /* Nope, maybe it's an address which evaluates to a signal
1560 i = parse_and_eval_address (signum_exp);
1561 if (i >= NSIG || i < 0)
1562 error ("Signal number out of bounds.");
1568 printf_filtered ("\n");
1569 for (i = 0; i < NSIG; i++)
1576 printf_filtered ("\nUse the \"handle\" command to change these tables.\n");
1579 /* Save all of the information associated with the inferior<==>gdb
1580 connection. INF_STATUS is a pointer to a "struct inferior_status"
1581 (defined in inferior.h). */
1584 save_inferior_status (inf_status, restore_stack_info)
1585 struct inferior_status *inf_status;
1586 int restore_stack_info;
1588 inf_status->pc_changed = pc_changed;
1589 inf_status->stop_signal = stop_signal;
1590 inf_status->stop_pc = stop_pc;
1591 inf_status->stop_frame_address = stop_frame_address;
1592 inf_status->stop_step = stop_step;
1593 inf_status->stop_stack_dummy = stop_stack_dummy;
1594 inf_status->stopped_by_random_signal = stopped_by_random_signal;
1595 inf_status->trap_expected = trap_expected;
1596 inf_status->step_range_start = step_range_start;
1597 inf_status->step_range_end = step_range_end;
1598 inf_status->step_frame_address = step_frame_address;
1599 inf_status->step_over_calls = step_over_calls;
1600 inf_status->step_resume_break_address = step_resume_break_address;
1601 inf_status->stop_after_trap = stop_after_trap;
1602 inf_status->stop_soon_quietly = stop_soon_quietly;
1603 /* Save original bpstat chain here; replace it with copy of chain.
1604 If caller's caller is walking the chain, they'll be happier if we
1605 hand them back the original chain when restore_i_s is called. */
1606 inf_status->stop_bpstat = stop_bpstat;
1607 stop_bpstat = bpstat_copy (stop_bpstat);
1608 inf_status->breakpoint_proceeded = breakpoint_proceeded;
1609 inf_status->restore_stack_info = restore_stack_info;
1610 inf_status->proceed_to_finish = proceed_to_finish;
1612 memcpy (inf_status->stop_registers, stop_registers, REGISTER_BYTES);
1614 record_selected_frame (&(inf_status->selected_frame_address),
1615 &(inf_status->selected_level));
1620 restore_inferior_status (inf_status)
1621 struct inferior_status *inf_status;
1624 int level = inf_status->selected_level;
1626 pc_changed = inf_status->pc_changed;
1627 stop_signal = inf_status->stop_signal;
1628 stop_pc = inf_status->stop_pc;
1629 stop_frame_address = inf_status->stop_frame_address;
1630 stop_step = inf_status->stop_step;
1631 stop_stack_dummy = inf_status->stop_stack_dummy;
1632 stopped_by_random_signal = inf_status->stopped_by_random_signal;
1633 trap_expected = inf_status->trap_expected;
1634 step_range_start = inf_status->step_range_start;
1635 step_range_end = inf_status->step_range_end;
1636 step_frame_address = inf_status->step_frame_address;
1637 step_over_calls = inf_status->step_over_calls;
1638 step_resume_break_address = inf_status->step_resume_break_address;
1639 stop_after_trap = inf_status->stop_after_trap;
1640 stop_soon_quietly = inf_status->stop_soon_quietly;
1641 bpstat_clear (&stop_bpstat);
1642 stop_bpstat = inf_status->stop_bpstat;
1643 breakpoint_proceeded = inf_status->breakpoint_proceeded;
1644 proceed_to_finish = inf_status->proceed_to_finish;
1646 memcpy (stop_registers, inf_status->stop_registers, REGISTER_BYTES);
1648 /* The inferior can be gone if the user types "print exit(0)"
1649 (and perhaps other times). */
1650 if (target_has_stack && inf_status->restore_stack_info)
1652 fid = find_relative_frame (get_current_frame (),
1655 /* If inf_status->selected_frame_address is NULL, there was no
1656 previously selected frame. */
1658 FRAME_FP (fid) != inf_status->selected_frame_address ||
1662 /* I'm not sure this error message is a good idea. I have
1663 only seen it occur after "Can't continue previously
1664 requested operation" (we get called from do_cleanups), in
1665 which case it just adds insult to injury (one confusing
1666 error message after another. Besides which, does the
1667 user really care if we can't restore the previously
1669 fprintf (stderr, "Unable to restore previously selected frame.\n");
1671 select_frame (get_current_frame (), 0);
1675 select_frame (fid, inf_status->selected_level);
1681 _initialize_infrun ()
1684 register int numsigs;
1686 add_info ("signals", signals_info,
1687 "What debugger does when program gets various signals.\n\
1688 Specify a signal number as argument to print info on that signal only.");
1689 add_info_alias ("handle", "signals", 0);
1691 add_com ("handle", class_run, handle_command,
1692 "Specify how to handle a signal.\n\
1693 Args are signal numbers and actions to apply to those signals.\n\
1694 Signal numbers may be numeric (ex. 11) or symbolic (ex. SIGSEGV).\n\
1695 Numeric ranges may be specified with the form LOW-HIGH (ex. 14-21).\n\
1696 The special arg \"all\" is recognized to mean all signals except those\n\
1697 used by the debugger, typically SIGTRAP and SIGINT.\n\
1698 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
1699 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
1700 Stop means reenter debugger if this signal happens (implies print).\n\
1701 Print means print a message if this signal happens.\n\
1702 Pass means let program see this signal; otherwise program doesn't know.\n\
1703 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
1704 Pass and Stop may be combined.");
1706 stop_command = add_cmd ("stop", class_obscure, not_just_help_class_command,
1707 "There is no `stop' command, but you can set a hook on `stop'.\n\
1708 This allows you to set a list of commands to be run each time execution\n\
1709 of the inferior program stops.", &cmdlist);
1711 numsigs = signo_max () + 1;
1712 signal_stop = (unsigned char *)
1713 xmalloc (sizeof (signal_stop[0]) * numsigs);
1714 signal_print = (unsigned char *)
1715 xmalloc (sizeof (signal_print[0]) * numsigs);
1716 signal_program = (unsigned char *)
1717 xmalloc (sizeof (signal_program[0]) * numsigs);
1718 for (i = 0; i < numsigs; i++)
1721 signal_print[i] = 1;
1722 signal_program[i] = 1;
1725 /* Signals caused by debugger's own actions
1726 should not be given to the program afterwards. */
1727 signal_program[SIGTRAP] = 0;
1728 signal_program[SIGINT] = 0;
1730 /* Signals that are not errors should not normally enter the debugger. */
1732 signal_stop[SIGALRM] = 0;
1733 signal_print[SIGALRM] = 0;
1734 #endif /* SIGALRM */
1736 signal_stop[SIGVTALRM] = 0;
1737 signal_print[SIGVTALRM] = 0;
1738 #endif /* SIGVTALRM */
1740 signal_stop[SIGPROF] = 0;
1741 signal_print[SIGPROF] = 0;
1742 #endif /* SIGPROF */
1744 signal_stop[SIGCHLD] = 0;
1745 signal_print[SIGCHLD] = 0;
1746 #endif /* SIGCHLD */
1748 signal_stop[SIGCLD] = 0;
1749 signal_print[SIGCLD] = 0;
1752 signal_stop[SIGIO] = 0;
1753 signal_print[SIGIO] = 0;
1756 signal_stop[SIGURG] = 0;
1757 signal_print[SIGURG] = 0;