[ViewVC] Diff of: cebix/BasiliskII/src/Unix/sigsegv.cpp

Comparing BasiliskII/src/Unix/sigsegv.cpp (file contents):
Revision 1.25 by gbeauche, 2003-09-29T08:02:04Z vs.
Revision 1.33 by gbeauche, 2003-10-21T23:10:19Z

#	Line 4 \| Line 4
4		* Derived from Bruno Haible's work on his SIGSEGV library for clisp
5		* <http://clisp.sourceforge.net/>
6		*
7	+	* MacOS X support derived from the post by Timothy J. Wood to the
8	+	* omnigroup macosx-dev list:
9	+	* Mach Exception Handlers 101 (Was Re: ptrace, gdb)
10	+	* tjw@omnigroup.com Sun, 4 Jun 2000
11	+	* www.omnigroup.com/mailman/archive/macosx-dev/2000-June/002030.html
12	+	*
13		* Basilisk II (C) 1997-2002 Christian Bauer
14		*
15		* This program is free software; you can redistribute it and/or modify
#	Line 212 \| Line 218 \| static void powerpc_decode_instruction(i
218		#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV)
219		#endif
220		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, siginfo_t sip, void scp
221	+	#define SIGSEGV_FAULT_HANDLER_ARGLIST_1 siginfo_t sip, void scp
222	+	#define SIGSEGV_FAULT_HANDLER_ARGS sip, scp
223		#define SIGSEGV_FAULT_ADDRESS sip->si_addr
224	<	#if defined(__NetBSD__) \|\| defined(__FreeBSD__)
224	>	#if defined(__sun__)
225	>	#if (defined(sparc) \|\| defined(__sparc__))
226	>	#include <sys/ucontext.h>
227	>	#define SIGSEGV_CONTEXT_REGS (((ucontext_t *)scp)->uc_mcontext.gregs)
228	>	#define SIGSEGV_FAULT_INSTRUCTION SIGSEGV_CONTEXT_REGS[REG_PC]
229	>	#endif
230	>	#endif
231	>	#if defined(__FreeBSD__)
232		#if (defined(i386) \|\| defined(__i386__))
233		#define SIGSEGV_FAULT_INSTRUCTION (((struct sigcontext *)scp)->sc_eip)
234		#define SIGSEGV_REGISTER_FILE ((unsigned int )&(((struct sigcontext )scp)->sc_edi)) /* EDI is the first GPR (even below EIP) in sigcontext */
#	Line 254 \| Line 269 \| static void powerpc_decode_instruction(i
269		#if (defined(i386) \|\| defined(__i386__))
270		#include <asm/sigcontext.h>
271		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, struct sigcontext scs
272	<	#define SIGSEGV_FAULT_ADDRESS scs.cr2
273	<	#define SIGSEGV_FAULT_INSTRUCTION scs.eip
274	<	#define SIGSEGV_REGISTER_FILE (unsigned int *)(&scs)
272	>	#define SIGSEGV_FAULT_HANDLER_ARGLIST_1 struct sigcontext *scp
273	>	#define SIGSEGV_FAULT_HANDLER_ARGS &scs
274	>	#define SIGSEGV_FAULT_ADDRESS scp->cr2
275	>	#define SIGSEGV_FAULT_INSTRUCTION scp->eip
276	>	#define SIGSEGV_REGISTER_FILE (unsigned int *)scp
277		#define SIGSEGV_SKIP_INSTRUCTION ix86_skip_instruction
278		#endif
279		#if (defined(sparc) \|\| defined(__sparc__))
280		#include <asm/sigcontext.h>
281		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext scp, char addr
282	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp, addr
283		#define SIGSEGV_FAULT_ADDRESS addr
284		#endif
285		#if (defined(powerpc) \|\| defined(__powerpc__))
286		#include <asm/sigcontext.h>
287		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, struct sigcontext *scp
288	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, scp
289		#define SIGSEGV_FAULT_ADDRESS scp->regs->dar
290		#define SIGSEGV_FAULT_INSTRUCTION scp->regs->nip
291		#define SIGSEGV_REGISTER_FILE (unsigned int )&scp->regs->nip, (unsigned int )(scp->regs->gpr)
#	Line 275 \| Line 294 \| static void powerpc_decode_instruction(i
294		#if (defined(alpha) \|\| defined(__alpha__))
295		#include <asm/sigcontext.h>
296		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp
297	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp
298		#define SIGSEGV_FAULT_ADDRESS get_fault_address(scp)
299		#define SIGSEGV_FAULT_INSTRUCTION scp->sc_pc
280	–
281	–	// From Boehm's GC 6.0alpha8
282	–	static sigsegv_address_t get_fault_address(struct sigcontext *scp)
283	–	{
284	–	unsigned int instruction = ((unsigned int )(scp->sc_pc));
285	–	unsigned long fault_address = scp->sc_regs[(instruction >> 16) & 0x1f];
286	–	fault_address += (signed long)(signed short)(instruction & 0xffff);
287	–	return (sigsegv_address_t)fault_address;
288	–	}
300		#endif
301		#endif
302
#	Line 293 \| Line 304 \| static sigsegv_address_t get_fault_addre
304		#if (defined(sgi) \|\| defined(__sgi)) && (defined(SYSTYPE_SVR4) \|\| defined(__SYSTYPE_SVR4))
305		#include <ucontext.h>
306		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp
307	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp
308		#define SIGSEGV_FAULT_ADDRESS scp->sc_badvaddr
309		#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV)
310		#endif
#	Line 300 \| Line 312 \| static sigsegv_address_t get_fault_addre
312		// HP-UX
313		#if (defined(hpux) \|\| defined(__hpux__))
314		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp
315	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp
316		#define SIGSEGV_FAULT_ADDRESS scp->sc_sl.sl_ss.ss_narrow.ss_cr21
317		#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV) FAULT_HANDLER(SIGBUS)
318		#endif
#	Line 308 \| Line 321 \| static sigsegv_address_t get_fault_addre
321		#if defined(__osf__)
322		#include <ucontext.h>
323		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp
324	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp
325		#define SIGSEGV_FAULT_ADDRESS scp->sc_traparg_a0
326		#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV)
327		#endif
#	Line 315 \| Line 329 \| static sigsegv_address_t get_fault_addre
329		// AIX
330		#if defined(_AIX)
331		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp
332	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp
333		#define SIGSEGV_FAULT_ADDRESS scp->sc_jmpbuf.jmp_context.o_vaddr
334		#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV)
335		#endif
336
337	<	// NetBSD or FreeBSD
338	<	#if defined(__NetBSD__) \|\| defined(__FreeBSD__)
337	>	// NetBSD
338	>	#if defined(__NetBSD__)
339		#if (defined(m68k) \|\| defined(__m68k__))
340		#include <m68k/frame.h>
341		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp
342	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp
343		#define SIGSEGV_FAULT_ADDRESS get_fault_address(scp)
344		#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV)
345
#	Line 347 \| Line 363 \| static sigsegv_address_t get_fault_addre
363		}
364		return (sigsegv_address_t)fault_addr;
365		}
366	<	#else
367	<	#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, void scp, char addr
368	<	#define SIGSEGV_FAULT_ADDRESS addr
366	>	#endif
367	>	#if (defined(alpha) \|\| defined(__alpha__))
368	>	#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp
369	>	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp
370	>	#define SIGSEGV_FAULT_ADDRESS get_fault_address(scp)
371	>	#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGBUS)
372	>	#endif
373	>	#if (defined(i386) \|\| defined(__i386__))
374	>	#error "FIXME: need to decode instruction and compute EA"
375	>	#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp
376	>	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp
377	>	#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV)
378	>	#endif
379	>	#endif
380	>	#if defined(__FreeBSD__)
381		#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGBUS)
382	+	#if (defined(i386) \|\| defined(__i386__))
383	+	#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext scp, char addr
384	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp, addr
385	+	#define SIGSEGV_FAULT_ADDRESS addr
386	+	#define SIGSEGV_FAULT_INSTRUCTION scp->sc_eip
387	+	#define SIGSEGV_REGISTER_FILE ((unsigned int *)&scp->sc_edi)
388	+	#define SIGSEGV_SKIP_INSTRUCTION ix86_skip_instruction
389	+	#endif
390		#endif
391	+
392	+	// Extract fault address out of a sigcontext
393	+	#if (defined(alpha) \|\| defined(__alpha__))
394	+	// From Boehm's GC 6.0alpha8
395	+	static sigsegv_address_t get_fault_address(struct sigcontext *scp)
396	+	{
397	+	unsigned int instruction = ((unsigned int )(scp->sc_pc));
398	+	unsigned long fault_address = scp->sc_regs[(instruction >> 16) & 0x1f];
399	+	fault_address += (signed long)(signed short)(instruction & 0xffff);
400	+	return (sigsegv_address_t)fault_address;
401	+	}
402		#endif
403
404	<	// MacOS X
404	>
405	>	// MacOS X, not sure which version this works in. Under 10.1
406	>	// vm_protect does not appear to work from a signal handler. Under
407	>	// 10.2 signal handlers get siginfo type arguments but the si_addr
408	>	// field is the address of the faulting instruction and not the
409	>	// address that caused the SIGBUS. Maybe this works in 10.0? In any
410	>	// case with Mach exception handlers there is a way to do what this
411	>	// was meant to do.
412	>	#ifndef HAVE_MACH_EXCEPTIONS
413		#if defined(__APPLE__) && defined(__MACH__)
414		#if (defined(ppc) \|\| defined(__ppc__))
415		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp
416	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp
417		#define SIGSEGV_FAULT_ADDRESS get_fault_address(scp)
418		#define SIGSEGV_FAULT_INSTRUCTION scp->sc_ir
419		#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGBUS)
#	Line 377 \| Line 433 \| static sigsegv_address_t get_fault_addre
433		#endif
434		#endif
435		#endif
436	+	#endif
437	+
438	+	#if HAVE_MACH_EXCEPTIONS
439	+
440	+	// This can easily be extended to other Mach systems, but really who
441	+	// uses HURD (oops GNU/HURD), Darwin/x86, NextStep, Rhapsody, or CMU
442	+	// Mach 2.5/3.0?
443	+	#if defined(__APPLE__) && defined(__MACH__)
444	+
445	+	#include <sys/types.h>
446	+	#include <stdlib.h>
447	+	#include <stdio.h>
448	+	#include <pthread.h>
449	+
450	+	/*
451	+	* If you are familiar with MIG then you will understand the frustration
452	+	* that was necessary to get these embedded into C++ code by hand.
453	+	*/
454	+	extern "C" {
455	+	#include <mach/mach.h>
456	+	#include <mach/mach_error.h>
457	+
458	+	extern boolean_t exc_server(mach_msg_header_t , mach_msg_header_t );
459	+	extern kern_return_t catch_exception_raise(mach_port_t, mach_port_t,
460	+	mach_port_t, exception_type_t, exception_data_t, mach_msg_type_number_t);
461	+	extern kern_return_t exception_raise(mach_port_t, mach_port_t, mach_port_t,
462	+	exception_type_t, exception_data_t, mach_msg_type_number_t);
463	+	extern kern_return_t exception_raise_state(mach_port_t, exception_type_t,
464	+	exception_data_t, mach_msg_type_number_t, thread_state_flavor_t *,
465	+	thread_state_t, mach_msg_type_number_t, thread_state_t, mach_msg_type_number_t *);
466	+	extern kern_return_t exception_raise_state_identity(mach_port_t, mach_port_t, mach_port_t,
467	+	exception_type_t, exception_data_t, mach_msg_type_number_t, thread_state_flavor_t *,
468	+	thread_state_t, mach_msg_type_number_t, thread_state_t, mach_msg_type_number_t *);
469	+	}
470	+
471	+	// Could make this dynamic by looking for a result of MIG_ARRAY_TOO_LARGE
472	+	#define HANDLER_COUNT 64
473	+
474	+	// structure to tuck away existing exception handlers
475	+	typedef struct _ExceptionPorts {
476	+	mach_msg_type_number_t maskCount;
477	+	exception_mask_t masks[HANDLER_COUNT];
478	+	exception_handler_t handlers[HANDLER_COUNT];
479	+	exception_behavior_t behaviors[HANDLER_COUNT];
480	+	thread_state_flavor_t flavors[HANDLER_COUNT];
481	+	} ExceptionPorts;
482	+
483	+	// exception handler thread
484	+	static pthread_t exc_thread;
485	+
486	+	// place where old exception handler info is stored
487	+	static ExceptionPorts ports;
488	+
489	+	// our exception port
490	+	static mach_port_t _exceptionPort = MACH_PORT_NULL;
491	+
492	+	#define MACH_CHECK_ERROR(name,ret) \
493	+	if (ret != KERN_SUCCESS) { \
494	+	mach_error(#name, ret); \
495	+	exit (1); \
496	+	}
497	+
498	+	#define SIGSEGV_FAULT_ADDRESS code[1]
499	+	#define SIGSEGV_FAULT_INSTRUCTION get_fault_instruction(thread, state)
500	+	#define SIGSEGV_FAULT_HANDLER_INVOKE(ADDR, IP) ((code[0] == KERN_PROTECTION_FAILURE) ? sigsegv_fault_handler(ADDR, IP) : SIGSEGV_RETURN_FAILURE)
501	+	#define SIGSEGV_FAULT_HANDLER_ARGLIST mach_port_t thread, exception_data_t code, ppc_thread_state_t *state
502	+	#define SIGSEGV_FAULT_HANDLER_ARGS thread, code, &state
503	+	#define SIGSEGV_SKIP_INSTRUCTION powerpc_skip_instruction
504	+	#define SIGSEGV_REGISTER_FILE &state->srr0, &state->r0
505	+
506	+	// Given a suspended thread, stuff the current instruction and
507	+	// registers into state.
508	+	//
509	+	// It would have been nice to have this be ppc/x86 independant which
510	+	// could have been done easily with a thread_state_t instead of
511	+	// ppc_thread_state_t, but because of the way this is called it is
512	+	// easier to do it this way.
513	+	#if (defined(ppc) \|\| defined(__ppc__))
514	+	static inline sigsegv_address_t get_fault_instruction(mach_port_t thread, ppc_thread_state_t *state)
515	+	{
516	+	kern_return_t krc;
517	+	mach_msg_type_number_t count;
518	+
519	+	count = MACHINE_THREAD_STATE_COUNT;
520	+	krc = thread_get_state(thread, MACHINE_THREAD_STATE, (thread_state_t)state, &count);
521	+	MACH_CHECK_ERROR (thread_get_state, krc);
522	+
523	+	return (sigsegv_address_t)state->srr0;
524	+	}
525	+	#endif
526	+
527	+	// Since there can only be one exception thread running at any time
528	+	// this is not a problem.
529	+	#define MSG_SIZE 512
530	+	static char msgbuf[MSG_SIZE];
531	+	static char replybuf[MSG_SIZE];
532	+
533	+	/*
534	+	* This is the entry point for the exception handler thread. The job
535	+	* of this thread is to wait for exception messages on the exception
536	+	* port that was setup beforehand and to pass them on to exc_server.
537	+	* exc_server is a MIG generated function that is a part of Mach.
538	+	* Its job is to decide what to do with the exception message. In our
539	+	* case exc_server calls catch_exception_raise on our behalf. After
540	+	* exc_server returns, it is our responsibility to send the reply.
541	+	*/
542	+	static void *
543	+	handleExceptions(void *priv)
544	+	{
545	+	mach_msg_header_t msg, reply;
546	+	kern_return_t krc;
547	+
548	+	msg = (mach_msg_header_t *)msgbuf;
549	+	reply = (mach_msg_header_t *)replybuf;
550	+
551	+	for (;;) {
552	+	krc = mach_msg(msg, MACH_RCV_MSG, MSG_SIZE, MSG_SIZE,
553	+	_exceptionPort, 0, MACH_PORT_NULL);
554	+	MACH_CHECK_ERROR(mach_msg, krc);
555	+
556	+	if (!exc_server(msg, reply)) {
557	+	fprintf(stderr, "exc_server hated the message\n");
558	+	exit(1);
559	+	}
560	+
561	+	krc = mach_msg(reply, MACH_SEND_MSG, reply->msgh_size, 0,
562	+	msg->msgh_local_port, 0, MACH_PORT_NULL);
563	+	if (krc != KERN_SUCCESS) {
564	+	fprintf(stderr, "Error sending message to original reply port, krc = %d, %s",
565	+	krc, mach_error_string(krc));
566	+	exit(1);
567	+	}
568	+	}
569	+	}
570	+	#endif
571	+	#endif
572
573
574		/*
#	Line 616 \| Line 808 \| static bool powerpc_skip_instruction(uns
808		#ifndef SIGSEGV_FAULT_INSTRUCTION
809		#define SIGSEGV_FAULT_INSTRUCTION SIGSEGV_INVALID_PC
810		#endif
811	+	#ifndef SIGSEGV_FAULT_HANDLER_ARGLIST_1
812	+	#define SIGSEGV_FAULT_HANDLER_ARGLIST_1 SIGSEGV_FAULT_HANDLER_ARGLIST
813	+	#endif
814	+	#ifndef SIGSEGV_FAULT_HANDLER_INVOKE
815	+	#define SIGSEGV_FAULT_HANDLER_INVOKE(ADDR, IP) sigsegv_fault_handler(ADDR, IP)
816	+	#endif
817
818		// SIGSEGV recovery supported ?
819		#if defined(SIGSEGV_ALL_SIGNALS) && defined(SIGSEGV_FAULT_HANDLER_ARGLIST) && defined(SIGSEGV_FAULT_ADDRESS)
#	Line 627 \| Line 825 \| static bool powerpc_skip_instruction(uns
825		* SIGSEGV global handler
826		*/
827
828	<	#ifdef HAVE_SIGSEGV_RECOVERY
829	<	static void sigsegv_handler(SIGSEGV_FAULT_HANDLER_ARGLIST)
828	>	#if defined(HAVE_SIGSEGV_RECOVERY) \|\| defined(HAVE_MACH_EXCEPTIONS)
829	>	// This function handles the badaccess to memory.
830	>	// It is called from the signal handler or the exception handler.
831	>	static bool handle_badaccess(SIGSEGV_FAULT_HANDLER_ARGLIST_1)
832		{
833		sigsegv_address_t fault_address = (sigsegv_address_t)SIGSEGV_FAULT_ADDRESS;
834		sigsegv_address_t fault_instruction = (sigsegv_address_t)SIGSEGV_FAULT_INSTRUCTION;
635	–	bool fault_recovered = false;
835
836		// Call user's handler and reinstall the global handler, if required
837	<	switch (sigsegv_fault_handler(fault_address, fault_instruction)) {
837	>	switch (SIGSEGV_FAULT_HANDLER_INVOKE(fault_address, fault_instruction)) {
838		case SIGSEGV_RETURN_SUCCESS:
839	<	#if (defined(HAVE_SIGACTION) ? defined(SIGACTION_NEED_REINSTALL) : defined(SIGNAL_NEED_REINSTALL))
840	<	sigsegv_do_install_handler(sig);
642	<	#endif
643	<	fault_recovered = true;
644	<	break;
839	>	return true;
840	>
841		#if HAVE_SIGSEGV_SKIP_INSTRUCTION
842		case SIGSEGV_RETURN_SKIP_INSTRUCTION:
843	<	// Call the instruction skipper with the register file available
844	<	if (SIGSEGV_SKIP_INSTRUCTION(SIGSEGV_REGISTER_FILE))
845	<	fault_recovered = true;
843	>	// Call the instruction skipper with the register file
844	>	// available
845	>	if (SIGSEGV_SKIP_INSTRUCTION(SIGSEGV_REGISTER_FILE)) {
846	>	#ifdef HAVE_MACH_EXCEPTIONS
847	>	// Unlike UNIX signals where the thread state
848	>	// is modified off of the stack, in Mach we
849	>	// need to actually call thread_set_state to
850	>	// have the register values updated.
851	>	kern_return_t krc;
852	>
853	>	krc = thread_set_state(thread,
854	>	MACHINE_THREAD_STATE, (thread_state_t)state,
855	>	MACHINE_THREAD_STATE_COUNT);
856	>	MACH_CHECK_ERROR (thread_get_state, krc);
857	>	#endif
858	>	return true;
859	>	}
860		break;
861		#endif
862		}
863	+
864	+	// We can't do anything with the fault_address, dump state?
865	+	if (sigsegv_state_dumper != 0)
866	+	sigsegv_state_dumper(fault_address, fault_instruction);
867
868	<	if (!fault_recovered) {
869	<	// Failure: reinstall default handler for "safe" crash
868	>	return false;
869	>	}
870	>	#endif
871	>
872	>
873	>	/*
874	>	* There are two mechanisms for handling a bad memory access,
875	>	* Mach exceptions and UNIX signals. The implementation specific
876	>	* code appears below. Its reponsibility is to call handle_badaccess
877	>	* which is the routine that handles the fault in an implementation
878	>	* agnostic manner. The implementation specific code below is then
879	>	* reponsible for checking whether handle_badaccess was able
880	>	* to handle the memory access error and perform any implementation
881	>	* specific tasks necessary afterwards.
882	>	*/
883	>
884	>	#ifdef HAVE_MACH_EXCEPTIONS
885	>	/*
886	>	* We need to forward all exceptions that we do not handle.
887	>	* This is important, there are many exceptions that may be
888	>	* handled by other exception handlers. For example debuggers
889	>	* use exceptions and the exception hander is in another
890	>	* process in such a case. (Timothy J. Wood states in his
891	>	* message to the list that he based this code on that from
892	>	* gdb for Darwin.)
893	>	*/
894	>	static inline kern_return_t
895	>	forward_exception(mach_port_t thread_port,
896	>	mach_port_t task_port,
897	>	exception_type_t exception_type,
898	>	exception_data_t exception_data,
899	>	mach_msg_type_number_t data_count,
900	>	ExceptionPorts *oldExceptionPorts)
901	>	{
902	>	kern_return_t kret;
903	>	unsigned int portIndex;
904	>	mach_port_t port;
905	>	exception_behavior_t behavior;
906	>	thread_state_flavor_t flavor;
907	>	thread_state_t thread_state;
908	>	mach_msg_type_number_t thread_state_count;
909	>
910	>	for (portIndex = 0; portIndex < oldExceptionPorts->maskCount; portIndex++) {
911	>	if (oldExceptionPorts->masks[portIndex] & (1 << exception_type)) {
912	>	// This handler wants the exception
913	>	break;
914	>	}
915	>	}
916	>
917	>	if (portIndex >= oldExceptionPorts->maskCount) {
918	>	fprintf(stderr, "No handler for exception_type = %d. Not fowarding\n", exception_type);
919	>	return KERN_FAILURE;
920	>	}
921	>
922	>	port = oldExceptionPorts->handlers[portIndex];
923	>	behavior = oldExceptionPorts->behaviors[portIndex];
924	>	flavor = oldExceptionPorts->flavors[portIndex];
925	>
926	>	/*
927	>	fprintf(stderr, "forwarding exception, port = 0x%x, behaviour = %d, flavor = %d\n", port, behavior, flavor);
928	>	*/
929	>
930	>	if (behavior != EXCEPTION_DEFAULT) {
931	>	thread_state_count = THREAD_STATE_MAX;
932	>	kret = thread_get_state (thread_port, flavor, thread_state,
933	>	&thread_state_count);
934	>	MACH_CHECK_ERROR (thread_get_state, kret);
935	>	}
936	>
937	>	switch (behavior) {
938	>	case EXCEPTION_DEFAULT:
939	>	// fprintf(stderr, "forwarding to exception_raise\n");
940	>	kret = exception_raise(port, thread_port, task_port, exception_type,
941	>	exception_data, data_count);
942	>	MACH_CHECK_ERROR (exception_raise, kret);
943	>	break;
944	>	case EXCEPTION_STATE:
945	>	// fprintf(stderr, "forwarding to exception_raise_state\n");
946	>	kret = exception_raise_state(port, exception_type, exception_data,
947	>	data_count, &flavor,
948	>	thread_state, thread_state_count,
949	>	thread_state, &thread_state_count);
950	>	MACH_CHECK_ERROR (exception_raise_state, kret);
951	>	break;
952	>	case EXCEPTION_STATE_IDENTITY:
953	>	// fprintf(stderr, "forwarding to exception_raise_state_identity\n");
954	>	kret = exception_raise_state_identity(port, thread_port, task_port,
955	>	exception_type, exception_data,
956	>	data_count, &flavor,
957	>	thread_state, thread_state_count,
958	>	thread_state, &thread_state_count);
959	>	MACH_CHECK_ERROR (exception_raise_state_identity, kret);
960	>	break;
961	>	default:
962	>	fprintf(stderr, "forward_exception got unknown behavior\n");
963	>	break;
964	>	}
965	>
966	>	if (behavior != EXCEPTION_DEFAULT) {
967	>	kret = thread_set_state (thread_port, flavor, thread_state,
968	>	thread_state_count);
969	>	MACH_CHECK_ERROR (thread_set_state, kret);
970	>	}
971	>
972	>	return KERN_SUCCESS;
973	>	}
974	>
975	>	/*
976	>	* This is the code that actually handles the exception.
977	>	* It is called by exc_server. For Darwin 5 Apple changed
978	>	* this a bit from how this family of functions worked in
979	>	* Mach. If you are familiar with that it is a little
980	>	* different. The main variation that concerns us here is
981	>	* that code is an array of exception specific codes and
982	>	* codeCount is a count of the number of codes in the code
983	>	* array. In typical Mach all exceptions have a code
984	>	* and sub-code. It happens to be the case that for a
985	>	* EXC_BAD_ACCESS exception the first entry is the type of
986	>	* bad access that occurred and the second entry is the
987	>	* faulting address so these entries correspond exactly to
988	>	* how the code and sub-code are used on Mach.
989	>	*
990	>	* This is a MIG interface. No code in Basilisk II should
991	>	* call this directley. This has to have external C
992	>	* linkage because that is what exc_server expects.
993	>	*/
994	>	kern_return_t
995	>	catch_exception_raise(mach_port_t exception_port,
996	>	mach_port_t thread,
997	>	mach_port_t task,
998	>	exception_type_t exception,
999	>	exception_data_t code,
1000	>	mach_msg_type_number_t codeCount)
1001	>	{
1002	>	ppc_thread_state_t state;
1003	>	kern_return_t krc;
1004	>
1005	>	if ((exception == EXC_BAD_ACCESS) && (codeCount >= 2)) {
1006	>	if (handle_badaccess(SIGSEGV_FAULT_HANDLER_ARGS))
1007	>	return KERN_SUCCESS;
1008	>	}
1009	>
1010	>	// In Mach we do not need to remove the exception handler.
1011	>	// If we forward the exception, eventually some exception handler
1012	>	// will take care of this exception.
1013	>	krc = forward_exception(thread, task, exception, code, codeCount, &ports);
1014	>
1015	>	return krc;
1016	>	}
1017	>	#endif
1018	>
1019	>	#ifdef HAVE_SIGSEGV_RECOVERY
1020	>	// Handle bad memory accesses with signal handler
1021	>	static void sigsegv_handler(SIGSEGV_FAULT_HANDLER_ARGLIST)
1022	>	{
1023	>	// Call handler and reinstall the global handler, if required
1024	>	if (handle_badaccess(SIGSEGV_FAULT_HANDLER_ARGS)) {
1025	>	#if (defined(HAVE_SIGACTION) ? defined(SIGACTION_NEED_REINSTALL) : defined(SIGNAL_NEED_REINSTALL))
1026	>	sigsegv_do_install_handler(sig);
1027	>	#endif
1028	>	return;
1029	>	}
1030	>
1031	>	// Failure: reinstall default handler for "safe" crash
1032		#define FAULT_HANDLER(sig) signal(sig, SIG_DFL);
1033	<	SIGSEGV_ALL_SIGNALS
1033	>	SIGSEGV_ALL_SIGNALS
1034		#undef FAULT_HANDLER
659	–
660	–	// We can't do anything with the fault_address, dump state?
661	–	if (sigsegv_state_dumper != 0)
662	–	sigsegv_state_dumper(fault_address, fault_instruction);
663	–	}
1035		}
1036		#endif
1037
#	Line 705 \| Line 1076 \| static bool sigsegv_do_install_handler(i
1076		}
1077		#endif
1078
1079	<	bool sigsegv_install_handler(sigsegv_fault_handler_t handler)
1079	>	#if defined(HAVE_MACH_EXCEPTIONS)
1080	>	static bool sigsegv_do_install_handler(sigsegv_fault_handler_t handler)
1081		{
1082	<	#ifdef HAVE_SIGSEGV_RECOVERY
1082	>	/*
1083	>	* Except for the exception port functions, this should be
1084	>	* pretty much stock Mach. If later you choose to support
1085	>	* other Mach's besides Darwin, just check for __MACH__
1086	>	* here and __APPLE__ where the actual differences are.
1087	>	*/
1088	>	#if defined(__APPLE__) && defined(__MACH__)
1089	>	if (sigsegv_fault_handler != NULL) {
1090	>	sigsegv_fault_handler = handler;
1091	>	return true;
1092	>	}
1093	>
1094	>	kern_return_t krc;
1095	>
1096	>	// create the the exception port
1097	>	krc = mach_port_allocate(mach_task_self(),
1098	>	MACH_PORT_RIGHT_RECEIVE, &_exceptionPort);
1099	>	if (krc != KERN_SUCCESS) {
1100	>	mach_error("mach_port_allocate", krc);
1101	>	return false;
1102	>	}
1103	>
1104	>	// add a port send right
1105	>	krc = mach_port_insert_right(mach_task_self(),
1106	>	_exceptionPort, _exceptionPort,
1107	>	MACH_MSG_TYPE_MAKE_SEND);
1108	>	if (krc != KERN_SUCCESS) {
1109	>	mach_error("mach_port_insert_right", krc);
1110	>	return false;
1111	>	}
1112	>
1113	>	// get the old exception ports
1114	>	ports.maskCount = sizeof (ports.masks) / sizeof (ports.masks[0]);
1115	>	krc = thread_get_exception_ports(mach_thread_self(), EXC_MASK_BAD_ACCESS, ports.masks,
1116	>	&ports.maskCount, ports.handlers, ports.behaviors, ports.flavors);
1117	>	if (krc != KERN_SUCCESS) {
1118	>	mach_error("thread_get_exception_ports", krc);
1119	>	return false;
1120	>	}
1121	>
1122	>	// set the new exception port
1123	>	//
1124	>	// We could have used EXCEPTION_STATE_IDENTITY instead of
1125	>	// EXCEPTION_DEFAULT to get the thread state in the initial
1126	>	// message, but it turns out that in the common case this is not
1127	>	// neccessary. If we need it we can later ask for it from the
1128	>	// suspended thread.
1129	>	//
1130	>	// Even with THREAD_STATE_NONE, Darwin provides the program
1131	>	// counter in the thread state. The comments in the header file
1132	>	// seem to imply that you can count on the GPR's on an exception
1133	>	// as well but just to be safe I use MACHINE_THREAD_STATE because
1134	>	// you have to ask for all of the GPR's anyway just to get the
1135	>	// program counter. In any case because of update effective
1136	>	// address from immediate and update address from effective
1137	>	// addresses of ra and rb modes (as good an name as any for these
1138	>	// addressing modes) used in PPC instructions, you will need the
1139	>	// GPR state anyway.
1140	>	krc = thread_set_exception_ports(mach_thread_self(), EXC_MASK_BAD_ACCESS, _exceptionPort,
1141	>	EXCEPTION_DEFAULT, MACHINE_THREAD_STATE);
1142	>	if (krc != KERN_SUCCESS) {
1143	>	mach_error("thread_set_exception_ports", krc);
1144	>	return false;
1145	>	}
1146	>
1147	>	// create the exception handler thread
1148	>	if (pthread_create(&exc_thread, NULL, &handleExceptions, NULL) != 0) {
1149	>	(void)fprintf(stderr, "creation of exception thread failed\n");
1150	>	return false;
1151	>	}
1152	>
1153	>	// do not care about the exception thread any longer, let is run standalone
1154	>	(void)pthread_detach(exc_thread);
1155	>
1156		sigsegv_fault_handler = handler;
1157	+	return true;
1158	+	#else
1159	+	return false;
1160	+	#endif
1161	+	}
1162	+	#endif
1163	+
1164	+	bool sigsegv_install_handler(sigsegv_fault_handler_t handler)
1165	+	{
1166	+	#if defined(HAVE_SIGSEGV_RECOVERY)
1167		bool success = true;
1168		#define FAULT_HANDLER(sig) success = success && sigsegv_do_install_handler(sig);
1169		SIGSEGV_ALL_SIGNALS
1170		#undef FAULT_HANDLER
1171	+	if (success)
1172	+	sigsegv_fault_handler = handler;
1173		return success;
1174	+	#elif defined(HAVE_MACH_EXCEPTIONS)
1175	+	return sigsegv_do_install_handler(handler);
1176		#else
1177		// FAIL: no siginfo_t nor sigcontext subterfuge is available
1178		return false;
#	Line 727 \| Line 1186 \| bool sigsegv_install_handler(sigsegv_fau
1186
1187		void sigsegv_deinstall_handler(void)
1188		{
1189	+	// We do nothing for Mach exceptions, the thread would need to be
1190	+	// suspended if not already so, and we might mess with other
1191	+	// exception handlers that came after we registered ours. There is
1192	+	// no need to remove the exception handler, in fact this function is
1193	+	// not called anywhere in Basilisk II.
1194		#ifdef HAVE_SIGSEGV_RECOVERY
1195		sigsegv_fault_handler = 0;
1196		#define FAULT_HANDLER(sig) signal(sig, SIG_DFL);
#	Line 757 \| Line 1221 \| void sigsegv_set_dump_state(sigsegv_stat
1221		#include <sys/mman.h>
1222		#include "vm_alloc.h"
1223
1224	+	const int REF_INDEX = 123;
1225	+	const int REF_VALUE = 45;
1226	+
1227		static int page_size;
1228		static volatile char * page = 0;
1229		static volatile int handler_called = 0;
1230
1231	+	#ifdef __GNUC__
1232	+	// Code range where we expect the fault to come from
1233	+	static void b_region, e_region;
1234	+	#endif
1235	+
1236		static sigsegv_return_t sigsegv_test_handler(sigsegv_address_t fault_address, sigsegv_address_t instruction_address)
1237		{
1238		handler_called++;
1239	<	if ((fault_address - 123) != page)
1240	<	exit(1);
1239	>	if ((fault_address - REF_INDEX) != page)
1240	>	exit(10);
1241	>	#ifdef __GNUC__
1242	>	// Make sure reported fault instruction address falls into
1243	>	// expected code range
1244	>	if (instruction_address != SIGSEGV_INVALID_PC
1245	>	&& ((instruction_address < (sigsegv_address_t)b_region) \|\|
1246	>	(instruction_address >= (sigsegv_address_t)e_region)))
1247	>	exit(11);
1248	>	#endif
1249		if (vm_protect((char *)((unsigned long)fault_address & -page_size), page_size, VM_PAGE_READ \| VM_PAGE_WRITE) != 0)
1250	<	exit(1);
1250	>	exit(12);
1251		return SIGSEGV_RETURN_SUCCESS;
1252		}
1253
1254		#ifdef HAVE_SIGSEGV_SKIP_INSTRUCTION
1255		static sigsegv_return_t sigsegv_insn_handler(sigsegv_address_t fault_address, sigsegv_address_t instruction_address)
1256		{
1257	<	if (((unsigned long)fault_address - (unsigned long)page) < page_size)
1258	<	return SIGSEGV_RETURN_KIP_INSTRUCTION;
1257	>	if (((unsigned long)fault_address - (unsigned long)page) < page_size) {
1258	>	#ifdef __GNUC__
1259	>	// Make sure reported fault instruction address falls into
1260	>	// expected code range
1261	>	if (instruction_address != SIGSEGV_INVALID_PC
1262	>	&& ((instruction_address < (sigsegv_address_t)b_region) \|\|
1263	>	(instruction_address >= (sigsegv_address_t)e_region)))
1264	>	return SIGSEGV_RETURN_FAILURE;
1265	>	#endif
1266	>	return SIGSEGV_RETURN_SKIP_INSTRUCTION;
1267	>	}
1268	>
1269		return SIGSEGV_RETURN_FAILURE;
1270		}
1271		#endif
#	Line 787 \| Line 1277 \| int main(void)
1277
1278		page_size = getpagesize();
1279		if ((page = (char *)vm_acquire(page_size)) == VM_MAP_FAILED)
1280	<	return 1;
1280	>	return 2;
1281
1282	+	memset((void *)page, 0, page_size);
1283		if (vm_protect((char *)page, page_size, VM_PAGE_READ) < 0)
1284	<	return 1;
1284	>	return 3;
1285
1286		if (!sigsegv_install_handler(sigsegv_test_handler))
1287	<	return 1;
797	<
798	<	page[123] = 45;
799	<	page[123] = 45;
1287	>	return 4;
1288
1289	+	#ifdef __GNUC__
1290	+	b_region = &&L_b_region1;
1291	+	e_region = &&L_e_region1;
1292	+	#endif
1293	+	L_b_region1:
1294	+	page[REF_INDEX] = REF_VALUE;
1295	+	if (page[REF_INDEX] != REF_VALUE)
1296	+	exit(20);
1297	+	page[REF_INDEX] = REF_VALUE;
1298	+	L_e_region1:
1299	+
1300		if (handler_called != 1)
1301	<	return 1;
1301	>	return 5;
1302
1303		#ifdef HAVE_SIGSEGV_SKIP_INSTRUCTION
1304		if (!sigsegv_install_handler(sigsegv_insn_handler))
1305	<	return 1;
1305	>	return 6;
1306
1307		if (vm_protect((char *)page, page_size, VM_PAGE_READ \| VM_PAGE_WRITE) < 0)
1308	<	return 1;
1308	>	return 7;
1309
1310		for (int i = 0; i < page_size; i++)
1311		page[i] = (i + 1) % page_size;
1312
1313		if (vm_protect((char *)page, page_size, VM_PAGE_NOACCESS) < 0)
1314	<	return 1;
1314	>	return 8;
1315
1316		#define TEST_SKIP_INSTRUCTION(TYPE) do { \
1317		const unsigned int TAG = 0x12345678; \
1318		TYPE data = ((TYPE )(page + sizeof(TYPE))); \
1319		volatile unsigned int effect = data + TAG; \
1320		if (effect != TAG) \
1321	<	return 1; \
1321	>	return 9; \
1322		} while (0)
1323
1324	+	#ifdef __GNUC__
1325	+	b_region = &&L_b_region2;
1326	+	e_region = &&L_e_region2;
1327	+	#endif
1328	+	L_b_region2:
1329		TEST_SKIP_INSTRUCTION(unsigned char);
1330		TEST_SKIP_INSTRUCTION(unsigned short);
1331		TEST_SKIP_INSTRUCTION(unsigned int);
1332	+	L_e_region2:
1333		#endif
1334
1335		vm_exit();
1336		return 0;
1337		}
1338		#endif
1339	+
1340	+
1341	+
1342	+
1343	+
1344	+
1345	+
1346	+
1347	+
1348	+
1349	+
1350	+
1351	+
1352	+
1353	+

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+Removed lines
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+Added lines
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+Changed lines
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Comparing BasiliskII/src/Unix/sigsegv.cpp (file contents): Revision 1.25 by gbeauche, 2003-09-29T08:02:04Z vs. Revision 1.33 by gbeauche, 2003-10-21T23:10:19Z

Diff Legend

Comparing BasiliskII/src/Unix/sigsegv.cpp (file contents):
Revision 1.25 by gbeauche, 2003-09-29T08:02:04Z vs.
Revision 1.33 by gbeauche, 2003-10-21T23:10:19Z