2 * interrupt-handling magic
6 * This software is part of the SBCL system. See the README file for
9 * This software is derived from the CMU CL system, which was
10 * written at Carnegie Mellon University and released into the
11 * public domain. The software is in the public domain and is
12 * provided with absolutely no warranty. See the COPYING and CREDITS
13 * files for more information.
17 /* As far as I can tell, what's going on here is:
19 * In the case of most signals, when Lisp asks us to handle the
20 * signal, the outermost handler (the one actually passed to UNIX) is
21 * either interrupt_handle_now(..) or maybe_now_maybe_later(..).
22 * In that case, the Lisp-level handler is stored in interrupt_handlers[..]
23 * and interrupt_low_level_handlers[..] is cleared.
25 * However, some signals need special handling, e.g.
27 * o the SIGSEGV (for e.g. Linux) or SIGBUS (for e.g. FreeBSD) used by the
28 * garbage collector to detect violations of write protection,
29 * because some cases of such signals (e.g. GC-related violations of
30 * write protection) are handled at C level and never passed on to
31 * Lisp. For such signals, we still store any Lisp-level handler
32 * in interrupt_handlers[..], but for the outermost handle we use
33 * the value from interrupt_low_level_handlers[..], instead of the
34 * ordinary interrupt_handle_now(..) or interrupt_handle_later(..).
36 * o the SIGTRAP (Linux/Alpha) which Lisp code uses to handle breakpoints,
37 * pseudo-atomic sections, and some classes of error (e.g. "function
38 * not defined"). This never goes anywhere near the Lisp handlers at all.
39 * See runtime/alpha-arch.c and code/signal.lisp
41 * - WHN 20000728, dan 20010128 */
49 #include <sys/types.h>
50 #ifndef LISP_FEATURE_WIN32
58 #include "interrupt.h"
66 #include "pseudo-atomic.h"
67 #include "genesis/fdefn.h"
68 #include "genesis/simple-fun.h"
69 #include "genesis/cons.h"
71 static void run_deferred_handler(struct interrupt_data *data, void *v_context);
72 #ifndef LISP_FEATURE_WIN32
73 static void store_signal_data_for_later (struct interrupt_data *data,
74 void *handler, int signal,
76 os_context_t *context);
79 fill_current_sigmask(sigset_t *sigset)
81 /* Get the current sigmask, by blocking the empty set. */
84 thread_sigmask(SIG_BLOCK, &empty, sigset);
88 sigaddset_deferrable(sigset_t *s)
92 sigaddset(s, SIGTERM);
93 sigaddset(s, SIGQUIT);
94 sigaddset(s, SIGPIPE);
95 sigaddset(s, SIGALRM);
97 sigaddset(s, SIGTSTP);
98 sigaddset(s, SIGCHLD);
100 #ifndef LISP_FEATURE_HPUX
101 sigaddset(s, SIGXCPU);
102 sigaddset(s, SIGXFSZ);
104 sigaddset(s, SIGVTALRM);
105 sigaddset(s, SIGPROF);
106 sigaddset(s, SIGWINCH);
108 #if !((defined(LISP_FEATURE_DARWIN) || defined(LISP_FEATURE_FREEBSD)) && defined(LISP_FEATURE_SB_THREAD))
109 sigaddset(s, SIGUSR1);
110 sigaddset(s, SIGUSR2);
113 #ifdef LISP_FEATURE_SB_THREAD
114 sigaddset(s, SIG_INTERRUPT_THREAD);
119 sigaddset_blockable(sigset_t *s)
121 sigaddset_deferrable(s);
122 #ifdef LISP_FEATURE_SB_THREAD
123 #ifdef SIG_RESUME_FROM_GC
124 sigaddset(s, SIG_RESUME_FROM_GC);
126 sigaddset(s, SIG_STOP_FOR_GC);
130 /* initialized in interrupt_init */
131 sigset_t deferrable_sigset;
132 sigset_t blockable_sigset;
136 check_deferrables_blocked_in_sigset_or_lose(sigset_t *sigset)
138 #if !defined(LISP_FEATURE_WIN32)
140 for(i = 1; i < NSIG; i++) {
141 if (sigismember(&deferrable_sigset, i) && !sigismember(sigset, i))
142 lose("deferrable signal %d not blocked\n",i);
148 check_deferrables_blocked_or_lose(void)
150 #if !defined(LISP_FEATURE_WIN32)
152 fill_current_sigmask(¤t);
153 check_deferrables_blocked_in_sigset_or_lose(¤t);
158 check_blockables_blocked_or_lose(void)
160 #if !defined(LISP_FEATURE_WIN32)
161 /* Get the current sigmask, by blocking the empty set. */
162 sigset_t empty,current;
165 thread_sigmask(SIG_BLOCK, &empty, ¤t);
166 for(i = 1; i < NSIG; i++) {
167 if (sigismember(&blockable_sigset, i) && !sigismember(¤t, i))
168 lose("blockable signal %d not blocked\n",i);
174 unblock_gc_signals(void)
176 #ifdef LISP_FEATURE_SB_THREAD
179 #if defined(SIG_RESUME_FROM_GC)
180 sigaddset(&new,SIG_RESUME_FROM_GC);
182 sigaddset(&new,SIG_STOP_FOR_GC);
183 thread_sigmask(SIG_UNBLOCK,&new,0);
188 check_interrupts_enabled_or_lose(os_context_t *context)
190 struct thread *thread=arch_os_get_current_thread();
191 if (SymbolValue(INTERRUPTS_ENABLED,thread) == NIL)
192 lose("interrupts not enabled\n");
193 if (arch_pseudo_atomic_atomic(context))
194 lose ("in pseudo atomic section\n");
197 /* When we catch an internal error, should we pass it back to Lisp to
198 * be handled in a high-level way? (Early in cold init, the answer is
199 * 'no', because Lisp is still too brain-dead to handle anything.
200 * After sufficient initialization has been completed, the answer
202 boolean internal_errors_enabled = 0;
204 #ifndef LISP_FEATURE_WIN32
205 static void (*interrupt_low_level_handlers[NSIG]) (int, siginfo_t*, void*);
207 union interrupt_handler interrupt_handlers[NSIG];
210 block_blockable_signals(void)
212 #ifndef LISP_FEATURE_WIN32
213 thread_sigmask(SIG_BLOCK, &blockable_sigset, 0);
218 block_deferrable_signals(void)
220 #ifndef LISP_FEATURE_WIN32
221 thread_sigmask(SIG_BLOCK, &deferrable_sigset, 0);
226 unblock_deferrable_signals(void)
228 #ifndef LISP_FEATURE_WIN32
229 thread_sigmask(SIG_UNBLOCK, &deferrable_sigset, 0);
235 * utility routines used by various signal handlers
239 build_fake_control_stack_frames(struct thread *th,os_context_t *context)
241 #ifndef LISP_FEATURE_C_STACK_IS_CONTROL_STACK
245 /* Build a fake stack frame or frames */
247 current_control_frame_pointer =
248 (lispobj *)(unsigned long)
249 (*os_context_register_addr(context, reg_CSP));
250 if ((lispobj *)(unsigned long)
251 (*os_context_register_addr(context, reg_CFP))
252 == current_control_frame_pointer) {
253 /* There is a small window during call where the callee's
254 * frame isn't built yet. */
255 if (lowtag_of(*os_context_register_addr(context, reg_CODE))
256 == FUN_POINTER_LOWTAG) {
257 /* We have called, but not built the new frame, so
258 * build it for them. */
259 current_control_frame_pointer[0] =
260 *os_context_register_addr(context, reg_OCFP);
261 current_control_frame_pointer[1] =
262 *os_context_register_addr(context, reg_LRA);
263 current_control_frame_pointer += 8;
264 /* Build our frame on top of it. */
265 oldcont = (lispobj)(*os_context_register_addr(context, reg_CFP));
268 /* We haven't yet called, build our frame as if the
269 * partial frame wasn't there. */
270 oldcont = (lispobj)(*os_context_register_addr(context, reg_OCFP));
273 /* We can't tell whether we are still in the caller if it had to
274 * allocate a stack frame due to stack arguments. */
275 /* This observation provoked some past CMUCL maintainer to ask
276 * "Can anything strange happen during return?" */
279 oldcont = (lispobj)(*os_context_register_addr(context, reg_CFP));
282 current_control_stack_pointer = current_control_frame_pointer + 8;
284 current_control_frame_pointer[0] = oldcont;
285 current_control_frame_pointer[1] = NIL;
286 current_control_frame_pointer[2] =
287 (lispobj)(*os_context_register_addr(context, reg_CODE));
291 /* Stores the context for gc to scavange and builds fake stack
294 fake_foreign_function_call(os_context_t *context)
297 struct thread *thread=arch_os_get_current_thread();
299 /* context_index incrementing must not be interrupted */
300 check_blockables_blocked_or_lose();
302 /* Get current Lisp state from context. */
304 dynamic_space_free_pointer =
305 (lispobj *)(unsigned long)
306 (*os_context_register_addr(context, reg_ALLOC));
307 /* fprintf(stderr,"dynamic_space_free_pointer: %p\n", */
308 /* dynamic_space_free_pointer); */
309 #if defined(LISP_FEATURE_ALPHA) || defined(LISP_FEATURE_MIPS)
310 if ((long)dynamic_space_free_pointer & 1) {
311 lose("dead in fake_foreign_function_call, context = %x\n", context);
314 /* why doesnt PPC and SPARC do something like this: */
315 #if defined(LISP_FEATURE_HPPA)
316 if ((long)dynamic_space_free_pointer & 4) {
317 lose("dead in fake_foreign_function_call, context = %x, d_s_f_p = %x\n", context, dynamic_space_free_pointer);
322 current_binding_stack_pointer =
323 (lispobj *)(unsigned long)
324 (*os_context_register_addr(context, reg_BSP));
327 build_fake_control_stack_frames(thread,context);
329 /* Do dynamic binding of the active interrupt context index
330 * and save the context in the context array. */
332 fixnum_value(SymbolValue(FREE_INTERRUPT_CONTEXT_INDEX,thread));
334 if (context_index >= MAX_INTERRUPTS) {
335 lose("maximum interrupt nesting depth (%d) exceeded\n", MAX_INTERRUPTS);
338 bind_variable(FREE_INTERRUPT_CONTEXT_INDEX,
339 make_fixnum(context_index + 1),thread);
341 thread->interrupt_contexts[context_index] = context;
343 #ifdef FOREIGN_FUNCTION_CALL_FLAG
344 foreign_function_call_active = 1;
348 /* blocks all blockable signals. If you are calling from a signal handler,
349 * the usual signal mask will be restored from the context when the handler
350 * finishes. Otherwise, be careful */
352 undo_fake_foreign_function_call(os_context_t *context)
354 struct thread *thread=arch_os_get_current_thread();
355 /* Block all blockable signals. */
356 block_blockable_signals();
358 #ifdef FOREIGN_FUNCTION_CALL_FLAG
359 foreign_function_call_active = 0;
362 /* Undo dynamic binding of FREE_INTERRUPT_CONTEXT_INDEX */
366 /* Put the dynamic space free pointer back into the context. */
367 *os_context_register_addr(context, reg_ALLOC) =
368 (unsigned long) dynamic_space_free_pointer
369 | (*os_context_register_addr(context, reg_ALLOC)
372 ((unsigned long)(*os_context_register_addr(context, reg_ALLOC))
374 | ((unsigned long) dynamic_space_free_pointer & LOWTAG_MASK);
379 /* a handler for the signal caused by execution of a trap opcode
380 * signalling an internal error */
382 interrupt_internal_error(os_context_t *context, boolean continuable)
386 fake_foreign_function_call(context);
388 if (!internal_errors_enabled) {
389 describe_internal_error(context);
390 /* There's no good way to recover from an internal error
391 * before the Lisp error handling mechanism is set up. */
392 lose("internal error too early in init, can't recover\n");
395 /* Allocate the SAP object while the interrupts are still
397 context_sap = alloc_sap(context);
399 #ifndef LISP_FEATURE_WIN32
400 thread_sigmask(SIG_SETMASK, os_context_sigmask_addr(context), 0);
403 #if defined(LISP_FEATURE_LINUX) && defined(LISP_FEATURE_MIPS)
404 /* Workaround for blocked SIGTRAP. */
407 sigemptyset(&newset);
408 sigaddset(&newset, SIGTRAP);
409 thread_sigmask(SIG_UNBLOCK, &newset, 0);
413 SHOW("in interrupt_internal_error");
415 /* Display some rudimentary debugging information about the
416 * error, so that even if the Lisp error handler gets badly
417 * confused, we have a chance to determine what's going on. */
418 describe_internal_error(context);
420 funcall2(StaticSymbolFunction(INTERNAL_ERROR), context_sap,
421 continuable ? T : NIL);
423 undo_fake_foreign_function_call(context); /* blocks signals again */
425 arch_skip_instruction(context);
429 interrupt_handle_pending(os_context_t *context)
431 /* There are three ways we can get here. First, if an interrupt
432 * occurs within pseudo-atomic, it will be deferred, and we'll
433 * trap to here at the end of the pseudo-atomic block. Second, if
434 * the GC (in alloc()) decides that a GC is required, it will set
435 * *GC-PENDING* and pseudo-atomic-interrupted if not *GC-INHIBIT*,
436 * and alloc() is always called from within pseudo-atomic, and
437 * thus we end up here again. Third, when calling GC-ON or at the
438 * end of a WITHOUT-GCING, MAYBE-HANDLE-PENDING-GC will trap to
439 * here if there is a pending GC. Fourth, ahem, at the end of
440 * WITHOUT-INTERRUPTS (bar complications with nesting). */
442 /* Win32 only needs to handle the GC cases (for now?) */
444 struct thread *thread;
446 if (arch_pseudo_atomic_atomic(context)) {
447 lose("Handling pending interrupt in pseduo atomic.");
450 thread = arch_os_get_current_thread();
452 FSHOW_SIGNAL((stderr, "/entering interrupt_handle_pending\n"));
454 check_blockables_blocked_or_lose();
456 /* If pseudo_atomic_interrupted is set then the interrupt is going
457 * to be handled now, ergo it's safe to clear it. */
458 arch_clear_pseudo_atomic_interrupted(context);
460 if (SymbolValue(GC_INHIBIT,thread)==NIL) {
461 #ifdef LISP_FEATURE_SB_THREAD
462 if (SymbolValue(STOP_FOR_GC_PENDING,thread) != NIL) {
463 /* STOP_FOR_GC_PENDING and GC_PENDING are cleared by
464 * the signal handler if it actually stops us. */
465 sig_stop_for_gc_handler(SIG_STOP_FOR_GC,NULL,context);
468 if (SymbolValue(GC_PENDING,thread) != NIL) {
469 /* GC_PENDING is cleared in SUB-GC, or if another thread
470 * is doing a gc already we will get a SIG_STOP_FOR_GC and
471 * that will clear it. */
474 check_blockables_blocked_or_lose();
477 #ifndef LISP_FEATURE_WIN32
478 /* we may be here only to do the gc stuff, if interrupts are
479 * enabled run the pending handler */
480 if (SymbolValue(INTERRUPTS_ENABLED,thread) != NIL) {
481 struct interrupt_data *data = thread->interrupt_data;
483 /* There may be no pending handler, because it was only a gc
484 * that had to be executed or because pseudo atomic triggered
485 * twice for a single interrupt. For the interested reader,
486 * that may happen if an interrupt hits after the interrupted
487 * flag is cleared but before pseudo-atomic is set and a
488 * pseudo atomic is interrupted in that interrupt. */
489 if (data->pending_handler) {
491 /* If we're here as the result of a pseudo-atomic as opposed
492 * to WITHOUT-INTERRUPTS, then INTERRUPT_PENDING is already
493 * NIL, because maybe_defer_handler sets
494 * PSEUDO_ATOMIC_INTERRUPTED only if interrupts are enabled.*/
495 SetSymbolValue(INTERRUPT_PENDING, NIL, thread);
497 /* restore the saved signal mask from the original signal (the
498 * one that interrupted us during the critical section) into the
499 * os_context for the signal we're currently in the handler for.
500 * This should ensure that when we return from the handler the
501 * blocked signals are unblocked */
502 sigcopyset(os_context_sigmask_addr(context), &data->pending_mask);
504 /* This will break on sparc linux: the deferred handler really wants
505 * to be called with a void_context */
506 run_deferred_handler(data,(void *)context);
513 * the two main signal handlers:
514 * interrupt_handle_now(..)
515 * maybe_now_maybe_later(..)
517 * to which we have added interrupt_handle_now_handler(..). Why?
518 * Well, mostly because the SPARC/Linux platform doesn't quite do
519 * signals the way we want them done. The third argument in the
520 * handler isn't filled in by the kernel properly, so we fix it up
521 * ourselves in the arch_os_get_context(..) function; however, we only
522 * want to do this when we first hit the handler, and not when
523 * interrupt_handle_now(..) is being called from some other handler
524 * (when the fixup will already have been done). -- CSR, 2002-07-23
528 interrupt_handle_now(int signal, siginfo_t *info, os_context_t *context)
530 #ifdef FOREIGN_FUNCTION_CALL_FLAG
531 boolean were_in_lisp;
533 union interrupt_handler handler;
535 check_blockables_blocked_or_lose();
537 #ifndef LISP_FEATURE_WIN32
538 if (sigismember(&deferrable_sigset,signal))
539 check_interrupts_enabled_or_lose(context);
542 #if defined(LISP_FEATURE_LINUX) || defined(RESTORE_FP_CONTROL_FROM_CONTEXT)
543 /* Under Linux on some architectures, we appear to have to restore
544 the FPU control word from the context, as after the signal is
545 delivered we appear to have a null FPU control word. */
546 os_restore_fp_control(context);
549 handler = interrupt_handlers[signal];
551 if (ARE_SAME_HANDLER(handler.c, SIG_IGN)) {
555 #ifdef FOREIGN_FUNCTION_CALL_FLAG
556 were_in_lisp = !foreign_function_call_active;
560 fake_foreign_function_call(context);
563 FSHOW_SIGNAL((stderr,
564 "/entering interrupt_handle_now(%d, info, context)\n",
567 if (ARE_SAME_HANDLER(handler.c, SIG_DFL)) {
569 /* This can happen if someone tries to ignore or default one
570 * of the signals we need for runtime support, and the runtime
571 * support decides to pass on it. */
572 lose("no handler for signal %d in interrupt_handle_now(..)\n", signal);
574 } else if (lowtag_of(handler.lisp) == FUN_POINTER_LOWTAG) {
575 /* Once we've decided what to do about contexts in a
576 * return-elsewhere world (the original context will no longer
577 * be available; should we copy it or was nobody using it anyway?)
578 * then we should convert this to return-elsewhere */
580 /* CMUCL comment said "Allocate the SAPs while the interrupts
581 * are still disabled.". I (dan, 2003.08.21) assume this is
582 * because we're not in pseudoatomic and allocation shouldn't
583 * be interrupted. In which case it's no longer an issue as
584 * all our allocation from C now goes through a PA wrapper,
585 * but still, doesn't hurt.
587 * Yeah, but non-gencgc platforms don't really wrap allocation
588 * in PA. MG - 2005-08-29 */
590 lispobj info_sap,context_sap = alloc_sap(context);
591 info_sap = alloc_sap(info);
592 /* Leave deferrable signals blocked, the handler itself will
593 * allow signals again when it sees fit. */
594 #ifdef LISP_FEATURE_SB_THREAD
597 sigemptyset(&unblock);
598 sigaddset(&unblock, SIG_STOP_FOR_GC);
599 #ifdef SIG_RESUME_FROM_GC
600 sigaddset(&unblock, SIG_RESUME_FROM_GC);
602 thread_sigmask(SIG_UNBLOCK, &unblock, 0);
606 FSHOW_SIGNAL((stderr,"/calling Lisp-level handler\n"));
608 funcall3(handler.lisp,
614 FSHOW_SIGNAL((stderr,"/calling C-level handler\n"));
616 #ifndef LISP_FEATURE_WIN32
617 /* Allow signals again. */
618 thread_sigmask(SIG_SETMASK, os_context_sigmask_addr(context), 0);
620 (*handler.c)(signal, info, context);
623 #ifdef FOREIGN_FUNCTION_CALL_FLAG
627 undo_fake_foreign_function_call(context); /* block signals again */
630 FSHOW_SIGNAL((stderr,
631 "/returning from interrupt_handle_now(%d, info, context)\n",
635 /* This is called at the end of a critical section if the indications
636 * are that some signal was deferred during the section. Note that as
637 * far as C or the kernel is concerned we dealt with the signal
638 * already; we're just doing the Lisp-level processing now that we
641 run_deferred_handler(struct interrupt_data *data, void *v_context)
643 /* The pending_handler may enable interrupts and then another
644 * interrupt may hit, overwrite interrupt_data, so reset the
645 * pending handler before calling it. Trust the handler to finish
646 * with the siginfo before enabling interrupts. */
647 void (*pending_handler) (int, siginfo_t*, void*)=data->pending_handler;
649 data->pending_handler=0;
650 (*pending_handler)(data->pending_signal,&(data->pending_info), v_context);
653 #ifndef LISP_FEATURE_WIN32
655 maybe_defer_handler(void *handler, struct interrupt_data *data,
656 int signal, siginfo_t *info, os_context_t *context)
658 struct thread *thread=arch_os_get_current_thread();
660 check_blockables_blocked_or_lose();
662 if (SymbolValue(INTERRUPT_PENDING,thread) != NIL)
663 lose("interrupt already pending\n");
664 /* If interrupts are disabled then INTERRUPT_PENDING is set and
665 * not PSEDUO_ATOMIC_INTERRUPTED. This is important for a pseudo
666 * atomic section inside a WITHOUT-INTERRUPTS.
668 if (SymbolValue(INTERRUPTS_ENABLED,thread) == NIL) {
669 store_signal_data_for_later(data,handler,signal,info,context);
670 SetSymbolValue(INTERRUPT_PENDING, T,thread);
671 FSHOW_SIGNAL((stderr,
672 "/maybe_defer_handler(%x,%d): deferred\n",
673 (unsigned int)handler,signal));
676 /* a slightly confusing test. arch_pseudo_atomic_atomic() doesn't
677 * actually use its argument for anything on x86, so this branch
678 * may succeed even when context is null (gencgc alloc()) */
679 if (arch_pseudo_atomic_atomic(context)) {
680 store_signal_data_for_later(data,handler,signal,info,context);
681 arch_set_pseudo_atomic_interrupted(context);
682 FSHOW_SIGNAL((stderr,
683 "/maybe_defer_handler(%x,%d): deferred(PA)\n",
684 (unsigned int)handler,signal));
687 FSHOW_SIGNAL((stderr,
688 "/maybe_defer_handler(%x,%d): not deferred\n",
689 (unsigned int)handler,signal));
694 store_signal_data_for_later (struct interrupt_data *data, void *handler,
696 siginfo_t *info, os_context_t *context)
698 if (data->pending_handler)
699 lose("tried to overwrite pending interrupt handler %x with %x\n",
700 data->pending_handler, handler);
702 lose("tried to defer null interrupt handler\n");
703 data->pending_handler = handler;
704 data->pending_signal = signal;
706 memcpy(&(data->pending_info), info, sizeof(siginfo_t));
708 FSHOW_SIGNAL((stderr, "/store_signal_data_for_later: signal: %d\n",
712 /* the signal mask in the context (from before we were
713 * interrupted) is copied to be restored when
714 * run_deferred_handler happens. Then the usually-blocked
715 * signals are added to the mask in the context so that we are
716 * running with blocked signals when the handler returns */
717 sigcopyset(&(data->pending_mask),os_context_sigmask_addr(context));
718 sigaddset_deferrable(os_context_sigmask_addr(context));
723 maybe_now_maybe_later(int signal, siginfo_t *info, void *void_context)
725 os_context_t *context = arch_os_get_context(&void_context);
726 struct thread *thread = arch_os_get_current_thread();
727 struct interrupt_data *data = thread->interrupt_data;
729 #if defined(LISP_FEATURE_LINUX) || defined(RESTORE_FP_CONTROL_FROM_CONTEXT)
730 os_restore_fp_control(context);
733 if(!maybe_defer_handler(interrupt_handle_now,data,signal,info,context))
734 interrupt_handle_now(signal, info, context);
738 low_level_interrupt_handle_now(int signal, siginfo_t *info,
739 os_context_t *context)
741 /* No FP control fixage needed, caller has done that. */
742 check_blockables_blocked_or_lose();
743 check_interrupts_enabled_or_lose(context);
744 (*interrupt_low_level_handlers[signal])(signal, info, context);
745 /* No Darwin context fixage needed, caller does that. */
749 low_level_maybe_now_maybe_later(int signal, siginfo_t *info, void *void_context)
751 os_context_t *context = arch_os_get_context(&void_context);
752 struct thread *thread = arch_os_get_current_thread();
753 struct interrupt_data *data = thread->interrupt_data;
755 #if defined(LISP_FEATURE_LINUX) || defined(RESTORE_FP_CONTROL_FROM_CONTEXT)
756 os_restore_fp_control(context);
759 if(!maybe_defer_handler(low_level_interrupt_handle_now,data,
760 signal,info,context))
761 low_level_interrupt_handle_now(signal, info, context);
765 #ifdef LISP_FEATURE_SB_THREAD
768 sig_stop_for_gc_handler(int signal, siginfo_t *info, void *void_context)
770 os_context_t *context = arch_os_get_context(&void_context);
772 struct thread *thread=arch_os_get_current_thread();
775 /* Test for GC_INHIBIT _first_, else we'd trap on every single
776 * pseudo atomic until gc is finally allowed. */
777 if (SymbolValue(GC_INHIBIT,thread) != NIL) {
778 SetSymbolValue(STOP_FOR_GC_PENDING,T,thread);
779 FSHOW_SIGNAL((stderr, "sig_stop_for_gc deferred (*GC-INHIBIT*)\n"));
781 } else if (arch_pseudo_atomic_atomic(context)) {
782 SetSymbolValue(STOP_FOR_GC_PENDING,T,thread);
783 arch_set_pseudo_atomic_interrupted(context);
784 FSHOW_SIGNAL((stderr,"sig_stop_for_gc deferred (PA)\n"));
788 /* Not PA and GC not inhibited -- we can stop now. */
790 /* need the context stored so it can have registers scavenged */
791 fake_foreign_function_call(context);
793 /* Block everything. */
795 thread_sigmask(SIG_BLOCK,&ss,0);
797 /* Not pending anymore. */
798 SetSymbolValue(GC_PENDING,NIL,thread);
799 SetSymbolValue(STOP_FOR_GC_PENDING,NIL,thread);
801 if(thread->state!=STATE_RUNNING) {
802 lose("sig_stop_for_gc_handler: wrong thread state: %ld\n",
803 fixnum_value(thread->state));
806 thread->state=STATE_SUSPENDED;
807 FSHOW_SIGNAL((stderr,"suspended\n"));
810 #if defined(SIG_RESUME_FROM_GC)
811 sigaddset(&ss,SIG_RESUME_FROM_GC);
813 sigaddset(&ss,SIG_STOP_FOR_GC);
816 /* It is possible to get SIGCONT (and probably other non-blockable
818 #ifdef SIG_RESUME_FROM_GC
821 do { sigwait(&ss, &sigret); }
822 while (sigret != SIG_RESUME_FROM_GC);
825 while (sigwaitinfo(&ss,0) != SIG_STOP_FOR_GC);
828 FSHOW_SIGNAL((stderr,"resumed\n"));
829 if(thread->state!=STATE_RUNNING) {
830 lose("sig_stop_for_gc_handler: wrong thread state on wakeup: %ld\n",
831 fixnum_value(thread->state));
834 undo_fake_foreign_function_call(context);
839 interrupt_handle_now_handler(int signal, siginfo_t *info, void *void_context)
841 os_context_t *context = arch_os_get_context(&void_context);
842 #if defined(LISP_FEATURE_LINUX) || defined(RESTORE_FP_CONTROL_FROM_CONTEXT)
843 os_restore_fp_control(context);
844 #ifndef LISP_FEATURE_WIN32
845 if ((signal == SIGILL) || (signal == SIGBUS)
846 #ifndef LISP_FEATURE_LINUX
847 || (signal == SIGEMT)
850 corruption_warning_and_maybe_lose("Signal %d recieved", signal);
853 interrupt_handle_now(signal, info, context);
856 /* manipulate the signal context and stack such that when the handler
857 * returns, it will call function instead of whatever it was doing
861 #if (defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64))
862 extern int *context_eflags_addr(os_context_t *context);
865 extern lispobj call_into_lisp(lispobj fun, lispobj *args, int nargs);
866 extern void post_signal_tramp(void);
867 extern void call_into_lisp_tramp(void);
869 arrange_return_to_lisp_function(os_context_t *context, lispobj function)
871 #if !(defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64))
872 void * fun=native_pointer(function);
873 void *code = &(((struct simple_fun *) fun)->code);
876 /* Build a stack frame showing `interrupted' so that the
877 * user's backtrace makes (as much) sense (as usual) */
879 /* FIXME: what about restoring fp state? */
880 /* FIXME: what about restoring errno? */
881 #ifdef LISP_FEATURE_X86
882 /* Suppose the existence of some function that saved all
883 * registers, called call_into_lisp, then restored GP registers and
884 * returned. It would look something like this:
892 pushl {address of function to call}
893 call 0x8058db0 <call_into_lisp>
900 * What we do here is set up the stack that call_into_lisp would
901 * expect to see if it had been called by this code, and frob the
902 * signal context so that signal return goes directly to call_into_lisp,
903 * and when that function (and the lisp function it invoked) returns,
904 * it returns to the second half of this imaginary function which
905 * restores all registers and returns to C
907 * For this to work, the latter part of the imaginary function
908 * must obviously exist in reality. That would be post_signal_tramp
911 u32 *sp=(u32 *)*os_context_register_addr(context,reg_ESP);
913 #if defined(LISP_FEATURE_DARWIN)
914 u32 *register_save_area = (u32 *)os_validate(0, 0x40);
916 FSHOW_SIGNAL((stderr, "/arrange_return_to_lisp_function: preparing to go to function %x, sp: %x\n", function, sp));
917 FSHOW_SIGNAL((stderr, "/arrange_return_to_lisp_function: context: %x, &context %x\n", context, &context));
919 /* 1. os_validate (malloc/mmap) register_save_block
920 * 2. copy register state into register_save_block
921 * 3. put a pointer to register_save_block in a register in the context
922 * 4. set the context's EIP to point to a trampoline which:
923 * a. builds the fake stack frame from the block
925 * c. calls the function
928 *register_save_area = *os_context_pc_addr(context);
929 *(register_save_area + 1) = function;
930 *(register_save_area + 2) = *os_context_register_addr(context,reg_EDI);
931 *(register_save_area + 3) = *os_context_register_addr(context,reg_ESI);
932 *(register_save_area + 4) = *os_context_register_addr(context,reg_EDX);
933 *(register_save_area + 5) = *os_context_register_addr(context,reg_ECX);
934 *(register_save_area + 6) = *os_context_register_addr(context,reg_EBX);
935 *(register_save_area + 7) = *os_context_register_addr(context,reg_EAX);
936 *(register_save_area + 8) = *context_eflags_addr(context);
938 *os_context_pc_addr(context) =
939 (os_context_register_t) call_into_lisp_tramp;
940 *os_context_register_addr(context,reg_ECX) =
941 (os_context_register_t) register_save_area;
944 /* return address for call_into_lisp: */
945 *(sp-15) = (u32)post_signal_tramp;
946 *(sp-14) = function; /* args for call_into_lisp : function*/
947 *(sp-13) = 0; /* arg array */
948 *(sp-12) = 0; /* no. args */
949 /* this order matches that used in POPAD */
950 *(sp-11)=*os_context_register_addr(context,reg_EDI);
951 *(sp-10)=*os_context_register_addr(context,reg_ESI);
953 *(sp-9)=*os_context_register_addr(context,reg_ESP)-8;
954 /* POPAD ignores the value of ESP: */
956 *(sp-7)=*os_context_register_addr(context,reg_EBX);
958 *(sp-6)=*os_context_register_addr(context,reg_EDX);
959 *(sp-5)=*os_context_register_addr(context,reg_ECX);
960 *(sp-4)=*os_context_register_addr(context,reg_EAX);
961 *(sp-3)=*context_eflags_addr(context);
962 *(sp-2)=*os_context_register_addr(context,reg_EBP);
963 *(sp-1)=*os_context_pc_addr(context);
967 #elif defined(LISP_FEATURE_X86_64)
968 u64 *sp=(u64 *)*os_context_register_addr(context,reg_RSP);
970 /* return address for call_into_lisp: */
971 *(sp-18) = (u64)post_signal_tramp;
973 *(sp-17)=*os_context_register_addr(context,reg_R15);
974 *(sp-16)=*os_context_register_addr(context,reg_R14);
975 *(sp-15)=*os_context_register_addr(context,reg_R13);
976 *(sp-14)=*os_context_register_addr(context,reg_R12);
977 *(sp-13)=*os_context_register_addr(context,reg_R11);
978 *(sp-12)=*os_context_register_addr(context,reg_R10);
979 *(sp-11)=*os_context_register_addr(context,reg_R9);
980 *(sp-10)=*os_context_register_addr(context,reg_R8);
981 *(sp-9)=*os_context_register_addr(context,reg_RDI);
982 *(sp-8)=*os_context_register_addr(context,reg_RSI);
983 /* skip RBP and RSP */
984 *(sp-7)=*os_context_register_addr(context,reg_RBX);
985 *(sp-6)=*os_context_register_addr(context,reg_RDX);
986 *(sp-5)=*os_context_register_addr(context,reg_RCX);
987 *(sp-4)=*os_context_register_addr(context,reg_RAX);
988 *(sp-3)=*context_eflags_addr(context);
989 *(sp-2)=*os_context_register_addr(context,reg_RBP);
990 *(sp-1)=*os_context_pc_addr(context);
992 *os_context_register_addr(context,reg_RDI) =
993 (os_context_register_t)function; /* function */
994 *os_context_register_addr(context,reg_RSI) = 0; /* arg. array */
995 *os_context_register_addr(context,reg_RDX) = 0; /* no. args */
997 struct thread *th=arch_os_get_current_thread();
998 build_fake_control_stack_frames(th,context);
1001 #ifdef LISP_FEATURE_X86
1003 #if !defined(LISP_FEATURE_DARWIN)
1004 *os_context_pc_addr(context) = (os_context_register_t)call_into_lisp;
1005 *os_context_register_addr(context,reg_ECX) = 0;
1006 *os_context_register_addr(context,reg_EBP) = (os_context_register_t)(sp-2);
1008 *os_context_register_addr(context,reg_UESP) =
1009 (os_context_register_t)(sp-15);
1011 *os_context_register_addr(context,reg_ESP) = (os_context_register_t)(sp-15);
1012 #endif /* __NETBSD__ */
1013 #endif /* LISP_FEATURE_DARWIN */
1015 #elif defined(LISP_FEATURE_X86_64)
1016 *os_context_pc_addr(context) = (os_context_register_t)call_into_lisp;
1017 *os_context_register_addr(context,reg_RCX) = 0;
1018 *os_context_register_addr(context,reg_RBP) = (os_context_register_t)(sp-2);
1019 *os_context_register_addr(context,reg_RSP) = (os_context_register_t)(sp-18);
1021 /* this much of the calling convention is common to all
1023 *os_context_pc_addr(context) = (os_context_register_t)(unsigned long)code;
1024 *os_context_register_addr(context,reg_NARGS) = 0;
1025 *os_context_register_addr(context,reg_LIP) =
1026 (os_context_register_t)(unsigned long)code;
1027 *os_context_register_addr(context,reg_CFP) =
1028 (os_context_register_t)(unsigned long)current_control_frame_pointer;
1030 #ifdef ARCH_HAS_NPC_REGISTER
1031 *os_context_npc_addr(context) =
1032 4 + *os_context_pc_addr(context);
1034 #ifdef LISP_FEATURE_SPARC
1035 *os_context_register_addr(context,reg_CODE) =
1036 (os_context_register_t)(fun + FUN_POINTER_LOWTAG);
1038 FSHOW((stderr, "/arranged return to Lisp function (0x%lx)\n",
1042 #ifdef LISP_FEATURE_SB_THREAD
1044 /* FIXME: this function can go away when all lisp handlers are invoked
1045 * via arrange_return_to_lisp_function. */
1047 interrupt_thread_handler(int num, siginfo_t *info, void *v_context)
1049 os_context_t *context = (os_context_t*)arch_os_get_context(&v_context);
1051 FSHOW_SIGNAL((stderr,"/interrupt_thread_handler\n"));
1052 check_blockables_blocked_or_lose();
1054 /* let the handler enable interrupts again when it sees fit */
1055 sigaddset_deferrable(os_context_sigmask_addr(context));
1056 arrange_return_to_lisp_function(context,
1057 StaticSymbolFunction(RUN_INTERRUPTION));
1062 /* KLUDGE: Theoretically the approach we use for undefined alien
1063 * variables should work for functions as well, but on PPC/Darwin
1064 * we get bus error at bogus addresses instead, hence this workaround,
1065 * that has the added benefit of automatically discriminating between
1066 * functions and variables.
1069 undefined_alien_function(void)
1071 funcall0(StaticSymbolFunction(UNDEFINED_ALIEN_FUNCTION_ERROR));
1075 handle_guard_page_triggered(os_context_t *context,os_vm_address_t addr)
1077 struct thread *th=arch_os_get_current_thread();
1079 /* note the os_context hackery here. When the signal handler returns,
1080 * it won't go back to what it was doing ... */
1081 if(addr >= CONTROL_STACK_GUARD_PAGE(th) &&
1082 addr < CONTROL_STACK_GUARD_PAGE(th) + os_vm_page_size) {
1083 /* We hit the end of the control stack: disable guard page
1084 * protection so the error handler has some headroom, protect the
1085 * previous page so that we can catch returns from the guard page
1086 * and restore it. */
1087 corruption_warning_and_maybe_lose("Control stack exhausted");
1088 protect_control_stack_guard_page(0);
1089 protect_control_stack_return_guard_page(1);
1091 arrange_return_to_lisp_function
1092 (context, StaticSymbolFunction(CONTROL_STACK_EXHAUSTED_ERROR));
1095 else if(addr >= CONTROL_STACK_RETURN_GUARD_PAGE(th) &&
1096 addr < CONTROL_STACK_RETURN_GUARD_PAGE(th) + os_vm_page_size) {
1097 /* We're returning from the guard page: reprotect it, and
1098 * unprotect this one. This works even if we somehow missed
1099 * the return-guard-page, and hit it on our way to new
1100 * exhaustion instead. */
1101 protect_control_stack_guard_page(1);
1102 protect_control_stack_return_guard_page(0);
1105 else if (addr >= undefined_alien_address &&
1106 addr < undefined_alien_address + os_vm_page_size) {
1107 arrange_return_to_lisp_function
1108 (context, StaticSymbolFunction(UNDEFINED_ALIEN_VARIABLE_ERROR));
1115 * noise to install handlers
1118 #ifndef LISP_FEATURE_WIN32
1119 /* In Linux 2.4 synchronous signals (sigtrap & co) can be delivered if
1120 * they are blocked, in Linux 2.6 the default handler is invoked
1121 * instead that usually coredumps. One might hastily think that adding
1122 * SA_NODEFER helps, but until ~2.6.13 if SA_NODEFER is specified then
1123 * the whole sa_mask is ignored and instead of not adding the signal
1124 * in question to the mask. That means if it's not blockable the
1125 * signal must be unblocked at the beginning of signal handlers.
1127 * It turns out that NetBSD's SA_NODEFER doesn't DTRT in a different
1128 * way: if SA_NODEFER is set and the signal is in sa_mask, the signal
1129 * will be unblocked in the sigmask during the signal handler. -- RMK
1132 static volatile int sigaction_nodefer_works = -1;
1134 #define SA_NODEFER_TEST_BLOCK_SIGNAL SIGABRT
1135 #define SA_NODEFER_TEST_KILL_SIGNAL SIGUSR1
1138 sigaction_nodefer_test_handler(int signal, siginfo_t *info, void *void_context)
1140 sigset_t empty, current;
1142 sigemptyset(&empty);
1143 thread_sigmask(SIG_BLOCK, &empty, ¤t);
1144 /* There should be exactly two blocked signals: the two we added
1145 * to sa_mask when setting up the handler. NetBSD doesn't block
1146 * the signal we're handling when SA_NODEFER is set; Linux before
1147 * 2.6.13 or so also doesn't block the other signal when
1148 * SA_NODEFER is set. */
1149 for(i = 1; i < NSIG; i++)
1150 if (sigismember(¤t, i) !=
1151 (((i == SA_NODEFER_TEST_BLOCK_SIGNAL) || (i == signal)) ? 1 : 0)) {
1152 FSHOW_SIGNAL((stderr, "SA_NODEFER doesn't work, signal %d\n", i));
1153 sigaction_nodefer_works = 0;
1155 if (sigaction_nodefer_works == -1)
1156 sigaction_nodefer_works = 1;
1160 see_if_sigaction_nodefer_works(void)
1162 struct sigaction sa, old_sa;
1164 sa.sa_flags = SA_SIGINFO | SA_NODEFER;
1165 sa.sa_sigaction = sigaction_nodefer_test_handler;
1166 sigemptyset(&sa.sa_mask);
1167 sigaddset(&sa.sa_mask, SA_NODEFER_TEST_BLOCK_SIGNAL);
1168 sigaddset(&sa.sa_mask, SA_NODEFER_TEST_KILL_SIGNAL);
1169 sigaction(SA_NODEFER_TEST_KILL_SIGNAL, &sa, &old_sa);
1170 /* Make sure no signals are blocked. */
1173 sigemptyset(&empty);
1174 thread_sigmask(SIG_SETMASK, &empty, 0);
1176 kill(getpid(), SA_NODEFER_TEST_KILL_SIGNAL);
1177 while (sigaction_nodefer_works == -1);
1178 sigaction(SA_NODEFER_TEST_KILL_SIGNAL, &old_sa, NULL);
1181 #undef SA_NODEFER_TEST_BLOCK_SIGNAL
1182 #undef SA_NODEFER_TEST_KILL_SIGNAL
1185 unblock_me_trampoline(int signal, siginfo_t *info, void *void_context)
1189 sigemptyset(&unblock);
1190 sigaddset(&unblock, signal);
1191 thread_sigmask(SIG_UNBLOCK, &unblock, 0);
1192 interrupt_handle_now_handler(signal, info, void_context);
1196 low_level_unblock_me_trampoline(int signal, siginfo_t *info, void *void_context)
1200 sigemptyset(&unblock);
1201 sigaddset(&unblock, signal);
1202 thread_sigmask(SIG_UNBLOCK, &unblock, 0);
1203 (*interrupt_low_level_handlers[signal])(signal, info, void_context);
1207 undoably_install_low_level_interrupt_handler (int signal,
1208 interrupt_handler_t handler)
1210 struct sigaction sa;
1212 if (0 > signal || signal >= NSIG) {
1213 lose("bad signal number %d\n", signal);
1216 if (ARE_SAME_HANDLER(handler, SIG_DFL))
1217 sa.sa_sigaction = handler;
1218 else if (sigismember(&deferrable_sigset,signal))
1219 sa.sa_sigaction = low_level_maybe_now_maybe_later;
1220 /* The use of a trampoline appears to break the
1221 arch_os_get_context() workaround for SPARC/Linux. For now,
1222 don't use the trampoline (and so be vulnerable to the problems
1223 that SA_NODEFER is meant to solve. */
1224 #if !(defined(LISP_FEATURE_SPARC) && defined(LISP_FEATURE_LINUX))
1225 else if (!sigaction_nodefer_works &&
1226 !sigismember(&blockable_sigset, signal))
1227 sa.sa_sigaction = low_level_unblock_me_trampoline;
1230 sa.sa_sigaction = handler;
1232 sigcopyset(&sa.sa_mask, &blockable_sigset);
1233 sa.sa_flags = SA_SIGINFO | SA_RESTART
1234 | (sigaction_nodefer_works ? SA_NODEFER : 0);
1235 #ifdef LISP_FEATURE_C_STACK_IS_CONTROL_STACK
1236 if((signal==SIG_MEMORY_FAULT)
1237 #ifdef SIG_INTERRUPT_THREAD
1238 || (signal==SIG_INTERRUPT_THREAD)
1241 sa.sa_flags |= SA_ONSTACK;
1244 sigaction(signal, &sa, NULL);
1245 interrupt_low_level_handlers[signal] =
1246 (ARE_SAME_HANDLER(handler, SIG_DFL) ? 0 : handler);
1250 /* This is called from Lisp. */
1252 install_handler(int signal, void handler(int, siginfo_t*, void*))
1254 #ifndef LISP_FEATURE_WIN32
1255 struct sigaction sa;
1257 union interrupt_handler oldhandler;
1259 FSHOW((stderr, "/entering POSIX install_handler(%d, ..)\n", signal));
1262 sigaddset(&new, signal);
1263 thread_sigmask(SIG_BLOCK, &new, &old);
1265 FSHOW((stderr, "/interrupt_low_level_handlers[signal]=%x\n",
1266 (unsigned int)interrupt_low_level_handlers[signal]));
1267 if (interrupt_low_level_handlers[signal]==0) {
1268 if (ARE_SAME_HANDLER(handler, SIG_DFL) ||
1269 ARE_SAME_HANDLER(handler, SIG_IGN))
1270 sa.sa_sigaction = handler;
1271 else if (sigismember(&deferrable_sigset, signal))
1272 sa.sa_sigaction = maybe_now_maybe_later;
1273 else if (!sigaction_nodefer_works &&
1274 !sigismember(&blockable_sigset, signal))
1275 sa.sa_sigaction = unblock_me_trampoline;
1277 sa.sa_sigaction = interrupt_handle_now_handler;
1279 sigcopyset(&sa.sa_mask, &blockable_sigset);
1280 sa.sa_flags = SA_SIGINFO | SA_RESTART |
1281 (sigaction_nodefer_works ? SA_NODEFER : 0);
1282 sigaction(signal, &sa, NULL);
1285 oldhandler = interrupt_handlers[signal];
1286 interrupt_handlers[signal].c = handler;
1288 thread_sigmask(SIG_SETMASK, &old, 0);
1290 FSHOW((stderr, "/leaving POSIX install_handler(%d, ..)\n", signal));
1292 return (unsigned long)oldhandler.lisp;
1294 /* Probably-wrong Win32 hack */
1299 /* This must not go through lisp as it's allowed anytime, even when on
1302 sigabrt_handler(int signal, siginfo_t *info, void *void_context)
1304 lose("SIGABRT received.\n");
1308 interrupt_init(void)
1310 #ifndef LISP_FEATURE_WIN32
1312 SHOW("entering interrupt_init()");
1313 see_if_sigaction_nodefer_works();
1314 sigemptyset(&deferrable_sigset);
1315 sigemptyset(&blockable_sigset);
1316 sigaddset_deferrable(&deferrable_sigset);
1317 sigaddset_blockable(&blockable_sigset);
1319 /* Set up high level handler information. */
1320 for (i = 0; i < NSIG; i++) {
1321 interrupt_handlers[i].c =
1322 /* (The cast here blasts away the distinction between
1323 * SA_SIGACTION-style three-argument handlers and
1324 * signal(..)-style one-argument handlers, which is OK
1325 * because it works to call the 1-argument form where the
1326 * 3-argument form is expected.) */
1327 (void (*)(int, siginfo_t*, void*))SIG_DFL;
1329 undoably_install_low_level_interrupt_handler(SIGABRT, sigabrt_handler);
1330 SHOW("returning from interrupt_init()");
1334 #ifndef LISP_FEATURE_WIN32
1336 siginfo_code(siginfo_t *info)
1338 return info->si_code;
1340 os_vm_address_t current_memory_fault_address;
1343 lisp_memory_fault_error(os_context_t *context, os_vm_address_t addr)
1345 /* FIXME: This is lossy: if we get another memory fault (eg. from
1346 * another thread) before lisp has read this, we lose the information.
1347 * However, since this is mostly informative, we'll live with that for
1348 * now -- some address is better then no address in this case.
1350 current_memory_fault_address = addr;
1351 /* To allow debugging memory faults in signal handlers and such. */
1352 corruption_warning_and_maybe_lose("Memory fault");
1353 arrange_return_to_lisp_function(context,
1354 StaticSymbolFunction(MEMORY_FAULT_ERROR));
1359 unhandled_trap_error(os_context_t *context)
1361 lispobj context_sap;
1362 fake_foreign_function_call(context);
1363 context_sap = alloc_sap(context);
1364 #ifndef LISP_FEATURE_WIN32
1365 thread_sigmask(SIG_SETMASK, os_context_sigmask_addr(context), 0);
1367 funcall1(StaticSymbolFunction(UNHANDLED_TRAP_ERROR), context_sap);
1368 lose("UNHANDLED-TRAP-ERROR fell through");
1371 /* Common logic for trapping instructions. How we actually handle each
1372 * case is highly architecture dependent, but the overall shape is
1375 handle_trap(os_context_t *context, int trap)
1378 case trap_PendingInterrupt:
1379 FSHOW((stderr, "/<trap pending interrupt>\n"));
1380 arch_skip_instruction(context);
1381 interrupt_handle_pending(context);
1385 FSHOW((stderr, "/<trap error/cerror %d>\n", trap));
1386 interrupt_internal_error(context, trap==trap_Cerror);
1388 case trap_Breakpoint:
1389 arch_handle_breakpoint(context);
1391 case trap_FunEndBreakpoint:
1392 arch_handle_fun_end_breakpoint(context);
1394 #ifdef trap_AfterBreakpoint
1395 case trap_AfterBreakpoint:
1396 arch_handle_after_breakpoint(context);
1399 #ifdef trap_SingleStepAround
1400 case trap_SingleStepAround:
1401 case trap_SingleStepBefore:
1402 arch_handle_single_step_trap(context, trap);
1406 fake_foreign_function_call(context);
1407 lose("%%PRIMITIVE HALT called; the party is over.\n");
1409 unhandled_trap_error(context);