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

Comparing BasiliskII/src/Unix/sigsegv.cpp (file contents):
Revision 1.21 by gbeauche, 2002-10-03T15:49:14Z vs.
Revision 1.29 by gbeauche, 2003-10-13T19:43:09Z

#	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 29 \| Line 35
35		#include "config.h"
36		#endif
37
38	+	#include <list>
39		#include <signal.h>
40		#include "sigsegv.h"
41
42	+	#ifndef NO_STD_NAMESPACE
43	+	using std::list;
44	+	#endif
45	+
46		// Return value type of a signal handler (standard type if not defined)
47		#ifndef RETSIGTYPE
48		#define RETSIGTYPE void
#	Line 40 \| Line 51
51		// Type of the system signal handler
52		typedef RETSIGTYPE (*signal_handler)(int);
53
43	–	// Is the fault to be ignored?
44	–	static bool sigsegv_ignore_fault = false;
45	–
54		// User's SIGSEGV handler
55		static sigsegv_fault_handler_t sigsegv_fault_handler = 0;
56
#	Line 57 \| Line 65 \| static bool sigsegv_do_install_handler(i
65		* Instruction decoding aids
66		*/
67
60	–	// Transfer type
61	–	enum transfer_type_t {
62	–	TYPE_UNKNOWN,
63	–	TYPE_LOAD,
64	–	TYPE_STORE
65	–	};
66	–
68		// Transfer size
69		enum transfer_size_t {
70		SIZE_UNKNOWN,
#	Line 72 \| Line 73 \| enum transfer_size_t {
73		SIZE_LONG
74		};
75
76	+	// Transfer type
77	+	typedef sigsegv_transfer_type_t transfer_type_t;
78	+
79		#if (defined(powerpc) \|\| defined(__powerpc__) \|\| defined(__ppc__))
80		// Addressing mode
81		enum addressing_mode_t {
#	Line 103 \| Line 107 \| static void powerpc_decode_instruction(i
107		signed int imm = (signed short)(opcode & 0xffff);
108
109		// Analyze opcode
110	<	transfer_type_t transfer_type = TYPE_UNKNOWN;
110	>	transfer_type_t transfer_type = SIGSEGV_TRANSFER_UNKNOWN;
111		transfer_size_t transfer_size = SIZE_UNKNOWN;
112		addressing_mode_t addr_mode = MODE_UNKNOWN;
113		switch (primop) {
114		case 31:
115		switch (exop) {
116		case 23: // lwzx
117	<	transfer_type = TYPE_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_X; break;
117	>	transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_X; break;
118		case 55: // lwzux
119	<	transfer_type = TYPE_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_UX; break;
119	>	transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_UX; break;
120		case 87: // lbzx
121	<	transfer_type = TYPE_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_X; break;
121	>	transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_X; break;
122		case 119: // lbzux
123	<	transfer_type = TYPE_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_UX; break;
123	>	transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_UX; break;
124		case 151: // stwx
125	<	transfer_type = TYPE_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_X; break;
125	>	transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_X; break;
126		case 183: // stwux
127	<	transfer_type = TYPE_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_UX; break;
127	>	transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_UX; break;
128		case 215: // stbx
129	<	transfer_type = TYPE_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_X; break;
129	>	transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_X; break;
130		case 247: // stbux
131	<	transfer_type = TYPE_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_UX; break;
131	>	transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_UX; break;
132		case 279: // lhzx
133	<	transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_X; break;
133	>	transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_X; break;
134		case 311: // lhzux
135	<	transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_UX; break;
135	>	transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_UX; break;
136		case 343: // lhax
137	<	transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_X; break;
137	>	transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_X; break;
138		case 375: // lhaux
139	<	transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_UX; break;
139	>	transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_UX; break;
140		case 407: // sthx
141	<	transfer_type = TYPE_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_X; break;
141	>	transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_X; break;
142		case 439: // sthux
143	<	transfer_type = TYPE_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_UX; break;
143	>	transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_UX; break;
144		}
145		break;
146
147		case 32: // lwz
148	<	transfer_type = TYPE_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_NORM; break;
148	>	transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_NORM; break;
149		case 33: // lwzu
150	<	transfer_type = TYPE_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_U; break;
150	>	transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_U; break;
151		case 34: // lbz
152	<	transfer_type = TYPE_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_NORM; break;
152	>	transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_NORM; break;
153		case 35: // lbzu
154	<	transfer_type = TYPE_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_U; break;
154	>	transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_U; break;
155		case 36: // stw
156	<	transfer_type = TYPE_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_NORM; break;
156	>	transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_NORM; break;
157		case 37: // stwu
158	<	transfer_type = TYPE_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_U; break;
158	>	transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_U; break;
159		case 38: // stb
160	<	transfer_type = TYPE_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_NORM; break;
160	>	transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_NORM; break;
161		case 39: // stbu
162	<	transfer_type = TYPE_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_U; break;
162	>	transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_U; break;
163		case 40: // lhz
164	<	transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_NORM; break;
164	>	transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_NORM; break;
165		case 41: // lhzu
166	<	transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_U; break;
166	>	transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_U; break;
167		case 42: // lha
168	<	transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_NORM; break;
168	>	transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_NORM; break;
169		case 43: // lhau
170	<	transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_U; break;
170	>	transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_U; break;
171		case 44: // sth
172	<	transfer_type = TYPE_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_NORM; break;
172	>	transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_NORM; break;
173		case 45: // sthu
174	<	transfer_type = TYPE_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_U; break;
174	>	transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_U; break;
175		}
176
177		// Calculate effective address
#	Line 208 \| Line 212 \| static void powerpc_decode_instruction(i
212
213		#if HAVE_SIGINFO_T
214		// Generic extended signal handler
215	+	#define SIGSEGV_FAULT_HANDLER sigsegv_fault_handler
216		#if defined(__NetBSD__) \|\| defined(__FreeBSD__)
217		#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGBUS)
218		#else
219		#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV)
220		#endif
221		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, siginfo_t sip, void scp
222	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, sip, scp
223		#define SIGSEGV_FAULT_ADDRESS sip->si_addr
224		#if defined(__NetBSD__) \|\| defined(__FreeBSD__)
225		#if (defined(i386) \|\| defined(__i386__))
#	Line 250 \| Line 256 \| static void powerpc_decode_instruction(i
256		#endif
257
258		#if HAVE_SIGCONTEXT_SUBTERFUGE
259	+	#define SIGSEGV_FAULT_HANDLER sigsegv_fault_handler
260		// Linux kernels prior to 2.4 ?
261		#if defined(__linux__)
262		#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV)
263		#if (defined(i386) \|\| defined(__i386__))
264		#include <asm/sigcontext.h>
265		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, struct sigcontext scs
266	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, scs
267		#define SIGSEGV_FAULT_ADDRESS scs.cr2
268		#define SIGSEGV_FAULT_INSTRUCTION scs.eip
269		#define SIGSEGV_REGISTER_FILE (unsigned int *)(&scs)
#	Line 264 \| Line 272 \| static void powerpc_decode_instruction(i
272		#if (defined(sparc) \|\| defined(__sparc__))
273		#include <asm/sigcontext.h>
274		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext scp, char addr
275	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp, addr
276		#define SIGSEGV_FAULT_ADDRESS addr
277		#endif
278		#if (defined(powerpc) \|\| defined(__powerpc__))
279		#include <asm/sigcontext.h>
280		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, struct sigcontext *scp
281	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, scp
282		#define SIGSEGV_FAULT_ADDRESS scp->regs->dar
283		#define SIGSEGV_FAULT_INSTRUCTION scp->regs->nip
284		#define SIGSEGV_REGISTER_FILE (unsigned int )&scp->regs->nip, (unsigned int )(scp->regs->gpr)
#	Line 277 \| Line 287 \| static void powerpc_decode_instruction(i
287		#if (defined(alpha) \|\| defined(__alpha__))
288		#include <asm/sigcontext.h>
289		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp
290	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp
291		#define SIGSEGV_FAULT_ADDRESS get_fault_address(scp)
292		#define SIGSEGV_FAULT_INSTRUCTION scp->sc_pc
293
#	Line 295 \| Line 306 \| static sigsegv_address_t get_fault_addre
306		#if (defined(sgi) \|\| defined(__sgi)) && (defined(SYSTYPE_SVR4) \|\| defined(__SYSTYPE_SVR4))
307		#include <ucontext.h>
308		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp
309	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp
310		#define SIGSEGV_FAULT_ADDRESS scp->sc_badvaddr
311		#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV)
312		#endif
#	Line 302 \| Line 314 \| static sigsegv_address_t get_fault_addre
314		// HP-UX
315		#if (defined(hpux) \|\| defined(__hpux__))
316		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp
317	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp
318		#define SIGSEGV_FAULT_ADDRESS scp->sc_sl.sl_ss.ss_narrow.ss_cr21
319		#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV) FAULT_HANDLER(SIGBUS)
320		#endif
#	Line 310 \| Line 323 \| static sigsegv_address_t get_fault_addre
323		#if defined(__osf__)
324		#include <ucontext.h>
325		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp
326	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp
327		#define SIGSEGV_FAULT_ADDRESS scp->sc_traparg_a0
328		#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV)
329		#endif
#	Line 317 \| Line 331 \| static sigsegv_address_t get_fault_addre
331		// AIX
332		#if defined(_AIX)
333		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp
334	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp
335		#define SIGSEGV_FAULT_ADDRESS scp->sc_jmpbuf.jmp_context.o_vaddr
336		#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV)
337		#endif
#	Line 326 \| Line 341 \| static sigsegv_address_t get_fault_addre
341		#if (defined(m68k) \|\| defined(__m68k__))
342		#include <m68k/frame.h>
343		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp
344	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp
345		#define SIGSEGV_FAULT_ADDRESS get_fault_address(scp)
346		#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV)
347
#	Line 351 \| Line 367 \| static sigsegv_address_t get_fault_addre
367		}
368		#else
369		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, void scp, char addr
370	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp, addr
371		#define SIGSEGV_FAULT_ADDRESS addr
372		#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGBUS)
373		#endif
374		#endif
375
376	<	// MacOS X
376	>	// MacOS X, not sure which version this works in. Under 10.1
377	>	// vm_protect does not appear to work from a signal handler. Under
378	>	// 10.2 signal handlers get siginfo type arguments but the si_addr
379	>	// field is the address of the faulting instruction and not the
380	>	// address that caused the SIGBUS. Maybe this works in 10.0? In any
381	>	// case with Mach exception handlers there is a way to do what this
382	>	// was meant to do.
383	>	#ifndef HAVE_MACH_EXCEPTIONS
384		#if defined(__APPLE__) && defined(__MACH__)
385		#if (defined(ppc) \|\| defined(__ppc__))
386		#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp
387	+	#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp
388		#define SIGSEGV_FAULT_ADDRESS get_fault_address(scp)
389		#define SIGSEGV_FAULT_INSTRUCTION scp->sc_ir
390		#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGBUS)
#	Line 379 \| Line 404 \| static sigsegv_address_t get_fault_addre
404		#endif
405		#endif
406		#endif
407	+	#endif
408	+
409	+	#if HAVE_MACH_EXCEPTIONS
410	+
411	+	// This can easily be extended to other Mach systems, but really who
412	+	// uses HURD (oops GNU/HURD), Darwin/x86, NextStep, Rhapsody, or CMU
413	+	// Mach 2.5/3.0?
414	+	#if defined(__APPLE__) && defined(__MACH__)
415	+
416	+	#include <sys/types.h>
417	+	#include <stdlib.h>
418	+	#include <stdio.h>
419	+	#include <pthread.h>
420	+
421	+	/*
422	+	* If you are familiar with MIG then you will understand the frustration
423	+	* that was necessary to get these embedded into C++ code by hand.
424	+	*/
425	+	extern "C" {
426	+	#include <mach/mach.h>
427	+	#include <mach/mach_error.h>
428	+
429	+	extern boolean_t exc_server(mach_msg_header_t , mach_msg_header_t );
430	+	extern kern_return_t catch_exception_raise(mach_port_t, mach_port_t,
431	+	mach_port_t, exception_type_t, exception_data_t, mach_msg_type_number_t);
432	+	extern kern_return_t exception_raise(mach_port_t, mach_port_t, mach_port_t,
433	+	exception_type_t, exception_data_t, mach_msg_type_number_t);
434	+	extern kern_return_t exception_raise_state(mach_port_t, exception_type_t,
435	+	exception_data_t, mach_msg_type_number_t, thread_state_flavor_t *,
436	+	thread_state_t, mach_msg_type_number_t, thread_state_t, mach_msg_type_number_t *);
437	+	extern kern_return_t exception_raise_state_identity(mach_port_t, mach_port_t, mach_port_t,
438	+	exception_type_t, exception_data_t, mach_msg_type_number_t, thread_state_flavor_t *,
439	+	thread_state_t, mach_msg_type_number_t, thread_state_t, mach_msg_type_number_t *);
440	+	}
441	+
442	+	// Could make this dynamic by looking for a result of MIG_ARRAY_TOO_LARGE
443	+	#define HANDLER_COUNT 64
444	+
445	+	// structure to tuck away existing exception handlers
446	+	typedef struct _ExceptionPorts {
447	+	mach_msg_type_number_t maskCount;
448	+	exception_mask_t masks[HANDLER_COUNT];
449	+	exception_handler_t handlers[HANDLER_COUNT];
450	+	exception_behavior_t behaviors[HANDLER_COUNT];
451	+	thread_state_flavor_t flavors[HANDLER_COUNT];
452	+	} ExceptionPorts;
453	+
454	+	// exception handler thread
455	+	static pthread_t exc_thread;
456	+
457	+	// place where old exception handler info is stored
458	+	static ExceptionPorts ports;
459	+
460	+	// our exception port
461	+	static mach_port_t _exceptionPort = MACH_PORT_NULL;
462	+
463	+	#define MACH_CHECK_ERROR(name,ret) \
464	+	if (ret != KERN_SUCCESS) { \
465	+	mach_error(#name, ret); \
466	+	exit (1); \
467	+	}
468	+
469	+	#define SIGSEGV_FAULT_ADDRESS code[1]
470	+	#define SIGSEGV_FAULT_INSTRUCTION get_fault_instruction(thread, state)
471	+	#define SIGSEGV_FAULT_HANDLER (code[0] == KERN_PROTECTION_FAILURE) && sigsegv_fault_handler
472	+	#define SIGSEGV_FAULT_HANDLER_ARGLIST mach_port_t thread, exception_data_t code, ppc_thread_state_t *state
473	+	#define SIGSEGV_FAULT_HANDLER_ARGS thread, code, &state
474	+	#define SIGSEGV_SKIP_INSTRUCTION powerpc_skip_instruction
475	+	#define SIGSEGV_REGISTER_FILE &state->srr0, &state->r0
476	+
477	+	// Given a suspended thread, stuff the current instruction and
478	+	// registers into state.
479	+	//
480	+	// It would have been nice to have this be ppc/x86 independant which
481	+	// could have been done easily with a thread_state_t instead of
482	+	// ppc_thread_state_t, but because of the way this is called it is
483	+	// easier to do it this way.
484	+	#if (defined(ppc) \|\| defined(__ppc__))
485	+	static inline sigsegv_address_t get_fault_instruction(mach_port_t thread, ppc_thread_state_t *state)
486	+	{
487	+	kern_return_t krc;
488	+	mach_msg_type_number_t count;
489	+
490	+	count = MACHINE_THREAD_STATE_COUNT;
491	+	krc = thread_get_state(thread, MACHINE_THREAD_STATE, (thread_state_t)state, &count);
492	+	MACH_CHECK_ERROR (thread_get_state, krc);
493	+
494	+	return (sigsegv_address_t)state->srr0;
495	+	}
496	+	#endif
497	+
498	+	// Since there can only be one exception thread running at any time
499	+	// this is not a problem.
500	+	#define MSG_SIZE 512
501	+	static char msgbuf[MSG_SIZE];
502	+	static char replybuf[MSG_SIZE];
503	+
504	+	/*
505	+	* This is the entry point for the exception handler thread. The job
506	+	* of this thread is to wait for exception messages on the exception
507	+	* port that was setup beforehand and to pass them on to exc_server.
508	+	* exc_server is a MIG generated function that is a part of Mach.
509	+	* Its job is to decide what to do with the exception message. In our
510	+	* case exc_server calls catch_exception_raise on our behalf. After
511	+	* exc_server returns, it is our responsibility to send the reply.
512	+	*/
513	+	static void *
514	+	handleExceptions(void *priv)
515	+	{
516	+	mach_msg_header_t msg, reply;
517	+	kern_return_t krc;
518	+
519	+	msg = (mach_msg_header_t *)msgbuf;
520	+	reply = (mach_msg_header_t *)replybuf;
521	+
522	+	for (;;) {
523	+	krc = mach_msg(msg, MACH_RCV_MSG, MSG_SIZE, MSG_SIZE,
524	+	_exceptionPort, 0, MACH_PORT_NULL);
525	+	MACH_CHECK_ERROR(mach_msg, krc);
526	+
527	+	if (!exc_server(msg, reply)) {
528	+	fprintf(stderr, "exc_server hated the message\n");
529	+	exit(1);
530	+	}
531	+
532	+	krc = mach_msg(reply, MACH_SEND_MSG, reply->msgh_size, 0,
533	+	msg->msgh_local_port, 0, MACH_PORT_NULL);
534	+	if (krc != KERN_SUCCESS) {
535	+	fprintf(stderr, "Error sending message to original reply port, krc = %d, %s",
536	+	krc, mach_error_string(krc));
537	+	exit(1);
538	+	}
539	+	}
540	+	}
541	+	#endif
542	+	#endif
543
544
545		/*
#	Line 455 \| Line 616 \| static bool ix86_skip_instruction(unsign
616		if (eip == 0)
617		return false;
618
619	<	transfer_type_t transfer_type = TYPE_UNKNOWN;
619	>	transfer_type_t transfer_type = SIGSEGV_TRANSFER_UNKNOWN;
620		transfer_size_t transfer_size = SIZE_LONG;
621
622		int reg = -1;
#	Line 477 \| Line 638 \| static bool ix86_skip_instruction(unsign
638		switch (eip[2] & 0xc0) {
639		case 0x80:
640		reg = (eip[2] >> 3) & 7;
641	<	transfer_type = TYPE_LOAD;
641	>	transfer_type = SIGSEGV_TRANSFER_LOAD;
642		break;
643		case 0x40:
644		reg = (eip[2] >> 3) & 7;
645	<	transfer_type = TYPE_LOAD;
645	>	transfer_type = SIGSEGV_TRANSFER_LOAD;
646		break;
647		case 0x00:
648		reg = (eip[2] >> 3) & 7;
649	<	transfer_type = TYPE_LOAD;
649	>	transfer_type = SIGSEGV_TRANSFER_LOAD;
650		break;
651		}
652		len += 3 + ix86_step_over_modrm(eip + 2);
#	Line 498 \| Line 659 \| static bool ix86_skip_instruction(unsign
659		switch (eip[1] & 0xc0) {
660		case 0x80:
661		reg = (eip[1] >> 3) & 7;
662	<	transfer_type = TYPE_LOAD;
662	>	transfer_type = SIGSEGV_TRANSFER_LOAD;
663		break;
664		case 0x40:
665		reg = (eip[1] >> 3) & 7;
666	<	transfer_type = TYPE_LOAD;
666	>	transfer_type = SIGSEGV_TRANSFER_LOAD;
667		break;
668		case 0x00:
669		reg = (eip[1] >> 3) & 7;
670	<	transfer_type = TYPE_LOAD;
670	>	transfer_type = SIGSEGV_TRANSFER_LOAD;
671		break;
672		}
673		len += 2 + ix86_step_over_modrm(eip + 1);
#	Line 517 \| Line 678 \| static bool ix86_skip_instruction(unsign
678		switch (eip[1] & 0xc0) {
679		case 0x80:
680		reg = (eip[1] >> 3) & 7;
681	<	transfer_type = TYPE_STORE;
681	>	transfer_type = SIGSEGV_TRANSFER_STORE;
682		break;
683		case 0x40:
684		reg = (eip[1] >> 3) & 7;
685	<	transfer_type = TYPE_STORE;
685	>	transfer_type = SIGSEGV_TRANSFER_STORE;
686		break;
687		case 0x00:
688		reg = (eip[1] >> 3) & 7;
689	<	transfer_type = TYPE_STORE;
689	>	transfer_type = SIGSEGV_TRANSFER_STORE;
690		break;
691		}
692		len += 2 + ix86_step_over_modrm(eip + 1);
693		break;
694		}
695
696	<	if (transfer_type == TYPE_UNKNOWN) {
696	>	if (transfer_type == SIGSEGV_TRANSFER_UNKNOWN) {
697		// Unknown machine code, let it crash. Then patch the decoder
698		return false;
699		}
700
701	<	if (transfer_type == TYPE_LOAD && reg != -1) {
701	>	if (transfer_type == SIGSEGV_TRANSFER_LOAD && reg != -1) {
702		static const int x86_reg_map[8] = {
703		X86_REG_EAX, X86_REG_ECX, X86_REG_EDX, X86_REG_EBX,
704		X86_REG_ESP, X86_REG_EBP, X86_REG_ESI, X86_REG_EDI
#	Line 563 \| Line 724 \| static bool ix86_skip_instruction(unsign
724		#if DEBUG
725		printf("%08x: %s %s access", regs[X86_REG_EIP],
726		transfer_size == SIZE_BYTE ? "byte" : transfer_size == SIZE_WORD ? "word" : "long",
727	<	transfer_type == TYPE_LOAD ? "read" : "write");
727	>	transfer_type == SIGSEGV_TRANSFER_LOAD ? "read" : "write");
728
729		if (reg != -1) {
730		static const char * x86_reg_str_map[8] = {
731		"eax", "ecx", "edx", "ebx",
732		"esp", "ebp", "esi", "edi"
733		};
734	<	printf(" %s register %%%s", transfer_type == TYPE_LOAD ? "to" : "from", x86_reg_str_map[reg]);
734	>	printf(" %s register %%%s", transfer_type == SIGSEGV_TRANSFER_LOAD ? "to" : "from", x86_reg_str_map[reg]);
735		}
736		printf(", %d bytes instruction\n", len);
737		#endif
#	Line 587 \| Line 748 \| static bool powerpc_skip_instruction(uns
748		instruction_t instr;
749		powerpc_decode_instruction(&instr, *nip_p, regs);
750
751	<	if (instr.transfer_type == TYPE_UNKNOWN) {
751	>	if (instr.transfer_type == SIGSEGV_TRANSFER_UNKNOWN) {
752		// Unknown machine code, let it crash. Then patch the decoder
753		return false;
754		}
#	Line 595 \| Line 756 \| static bool powerpc_skip_instruction(uns
756		#if DEBUG
757		printf("%08x: %s %s access", *nip_p,
758		instr.transfer_size == SIZE_BYTE ? "byte" : instr.transfer_size == SIZE_WORD ? "word" : "long",
759	<	instr.transfer_type == TYPE_LOAD ? "read" : "write");
759	>	instr.transfer_type == SIGSEGV_TRANSFER_LOAD ? "read" : "write");
760
761		if (instr.addr_mode == MODE_U \|\| instr.addr_mode == MODE_UX)
762		printf(" r%d (ra = %08x)\n", instr.ra, instr.addr);
763	<	if (instr.transfer_type == TYPE_LOAD)
763	>	if (instr.transfer_type == SIGSEGV_TRANSFER_LOAD)
764		printf(" r%d (rd = 0)\n", instr.rd);
765		#endif
766
767		if (instr.addr_mode == MODE_U \|\| instr.addr_mode == MODE_UX)
768		regs[instr.ra] = instr.addr;
769	<	if (instr.transfer_type == TYPE_LOAD)
769	>	if (instr.transfer_type == SIGSEGV_TRANSFER_LOAD)
770		regs[instr.rd] = 0;
771
772		*nip_p += 4;
#	Line 629 \| Line 790 \| static bool powerpc_skip_instruction(uns
790		* SIGSEGV global handler
791		*/
792
793	<	#ifdef HAVE_SIGSEGV_RECOVERY
794	<	static void sigsegv_handler(SIGSEGV_FAULT_HANDLER_ARGLIST)
793	>	#if defined(HAVE_SIGSEGV_RECOVERY) \|\| defined(HAVE_MACH_EXCEPTIONS)
794	>	// This function handles the badaccess to memory.
795	>	// It is called from the signal handler or the exception handler.
796	>	static bool handle_badaccess(SIGSEGV_FAULT_HANDLER_ARGLIST)
797		{
798		sigsegv_address_t fault_address = (sigsegv_address_t)SIGSEGV_FAULT_ADDRESS;
799		sigsegv_address_t fault_instruction = (sigsegv_address_t)SIGSEGV_FAULT_INSTRUCTION;
637	–	bool fault_recovered = false;
800
801		// Call user's handler and reinstall the global handler, if required
802	<	if (sigsegv_fault_handler(fault_address, fault_instruction)) {
803	<	#if (defined(HAVE_SIGACTION) ? defined(SIGACTION_NEED_REINSTALL) : defined(SIGNAL_NEED_REINSTALL))
804	<	sigsegv_do_install_handler(sig);
802	>	switch (sigsegv_fault_handler(fault_address, fault_instruction)) {
803	>	case SIGSEGV_RETURN_SUCCESS:
804	>	return true;
805	>
806	>	#if HAVE_SIGSEGV_SKIP_INSTRUCTION
807	>	case SIGSEGV_RETURN_SKIP_INSTRUCTION:
808	>	// Call the instruction skipper with the register file
809	>	// available
810	>	if (SIGSEGV_SKIP_INSTRUCTION(SIGSEGV_REGISTER_FILE)) {
811	>	#ifdef HAVE_MACH_EXCEPTIONS
812	>	// Unlike UNIX signals where the thread state
813	>	// is modified off of the stack, in Mach we
814	>	// need to actually call thread_set_state to
815	>	// have the register values updated.
816	>	kern_return_t krc;
817	>
818	>	krc = thread_set_state(thread,
819	>	MACHINE_THREAD_STATE, (thread_state_t)state,
820	>	MACHINE_THREAD_STATE_COUNT);
821	>	MACH_CHECK_ERROR (thread_get_state, krc);
822	>	#endif
823	>	return true;
824	>	}
825	>	break;
826		#endif
644	–	fault_recovered = true;
827		}
828	<	#if HAVE_SIGSEGV_SKIP_INSTRUCTION
829	<	else if (sigsegv_ignore_fault) {
830	<	// Call the instruction skipper with the register file available
831	<	if (SIGSEGV_SKIP_INSTRUCTION(SIGSEGV_REGISTER_FILE))
832	<	fault_recovered = true;
828	>
829	>	// We can't do anything with the fault_address, dump state?
830	>	if (sigsegv_state_dumper != 0)
831	>	sigsegv_state_dumper(fault_address, fault_instruction);
832	>
833	>	return false;
834	>	}
835	>	#endif
836	>
837	>
838	>	/*
839	>	* There are two mechanisms for handling a bad memory access,
840	>	* Mach exceptions and UNIX signals. The implementation specific
841	>	* code appears below. Its reponsibility is to call handle_badaccess
842	>	* which is the routine that handles the fault in an implementation
843	>	* agnostic manner. The implementation specific code below is then
844	>	* reponsible for checking whether handle_badaccess was able
845	>	* to handle the memory access error and perform any implementation
846	>	* specific tasks necessary afterwards.
847	>	*/
848	>
849	>	#ifdef HAVE_MACH_EXCEPTIONS
850	>	/*
851	>	* We need to forward all exceptions that we do not handle.
852	>	* This is important, there are many exceptions that may be
853	>	* handled by other exception handlers. For example debuggers
854	>	* use exceptions and the exception hander is in another
855	>	* process in such a case. (Timothy J. Wood states in his
856	>	* message to the list that he based this code on that from
857	>	* gdb for Darwin.)
858	>	*/
859	>	static inline kern_return_t
860	>	forward_exception(mach_port_t thread_port,
861	>	mach_port_t task_port,
862	>	exception_type_t exception_type,
863	>	exception_data_t exception_data,
864	>	mach_msg_type_number_t data_count,
865	>	ExceptionPorts *oldExceptionPorts)
866	>	{
867	>	kern_return_t kret;
868	>	unsigned int portIndex;
869	>	mach_port_t port;
870	>	exception_behavior_t behavior;
871	>	thread_state_flavor_t flavor;
872	>	thread_state_t thread_state;
873	>	mach_msg_type_number_t thread_state_count;
874	>
875	>	for (portIndex = 0; portIndex < oldExceptionPorts->maskCount; portIndex++) {
876	>	if (oldExceptionPorts->masks[portIndex] & (1 << exception_type)) {
877	>	// This handler wants the exception
878	>	break;
879	>	}
880	>	}
881	>
882	>	if (portIndex >= oldExceptionPorts->maskCount) {
883	>	fprintf(stderr, "No handler for exception_type = %d. Not fowarding\n", exception_type);
884	>	return KERN_FAILURE;
885	>	}
886	>
887	>	port = oldExceptionPorts->handlers[portIndex];
888	>	behavior = oldExceptionPorts->behaviors[portIndex];
889	>	flavor = oldExceptionPorts->flavors[portIndex];
890	>
891	>	/*
892	>	fprintf(stderr, "forwarding exception, port = 0x%x, behaviour = %d, flavor = %d\n", port, behavior, flavor);
893	>	*/
894	>
895	>	if (behavior != EXCEPTION_DEFAULT) {
896	>	thread_state_count = THREAD_STATE_MAX;
897	>	kret = thread_get_state (thread_port, flavor, thread_state,
898	>	&thread_state_count);
899	>	MACH_CHECK_ERROR (thread_get_state, kret);
900		}
901	+
902	+	switch (behavior) {
903	+	case EXCEPTION_DEFAULT:
904	+	// fprintf(stderr, "forwarding to exception_raise\n");
905	+	kret = exception_raise(port, thread_port, task_port, exception_type,
906	+	exception_data, data_count);
907	+	MACH_CHECK_ERROR (exception_raise, kret);
908	+	break;
909	+	case EXCEPTION_STATE:
910	+	// fprintf(stderr, "forwarding to exception_raise_state\n");
911	+	kret = exception_raise_state(port, exception_type, exception_data,
912	+	data_count, &flavor,
913	+	thread_state, thread_state_count,
914	+	thread_state, &thread_state_count);
915	+	MACH_CHECK_ERROR (exception_raise_state, kret);
916	+	break;
917	+	case EXCEPTION_STATE_IDENTITY:
918	+	// fprintf(stderr, "forwarding to exception_raise_state_identity\n");
919	+	kret = exception_raise_state_identity(port, thread_port, task_port,
920	+	exception_type, exception_data,
921	+	data_count, &flavor,
922	+	thread_state, thread_state_count,
923	+	thread_state, &thread_state_count);
924	+	MACH_CHECK_ERROR (exception_raise_state_identity, kret);
925	+	break;
926	+	default:
927	+	fprintf(stderr, "forward_exception got unknown behavior\n");
928	+	break;
929	+	}
930	+
931	+	if (behavior != EXCEPTION_DEFAULT) {
932	+	kret = thread_set_state (thread_port, flavor, thread_state,
933	+	thread_state_count);
934	+	MACH_CHECK_ERROR (thread_set_state, kret);
935	+	}
936	+
937	+	return KERN_SUCCESS;
938	+	}
939	+
940	+	/*
941	+	* This is the code that actually handles the exception.
942	+	* It is called by exc_server. For Darwin 5 Apple changed
943	+	* this a bit from how this family of functions worked in
944	+	* Mach. If you are familiar with that it is a little
945	+	* different. The main variation that concerns us here is
946	+	* that code is an array of exception specific codes and
947	+	* codeCount is a count of the number of codes in the code
948	+	* array. In typical Mach all exceptions have a code
949	+	* and sub-code. It happens to be the case that for a
950	+	* EXC_BAD_ACCESS exception the first entry is the type of
951	+	* bad access that occurred and the second entry is the
952	+	* faulting address so these entries correspond exactly to
953	+	* how the code and sub-code are used on Mach.
954	+	*
955	+	* This is a MIG interface. No code in Basilisk II should
956	+	* call this directley. This has to have external C
957	+	* linkage because that is what exc_server expects.
958	+	*/
959	+	kern_return_t
960	+	catch_exception_raise(mach_port_t exception_port,
961	+	mach_port_t thread,
962	+	mach_port_t task,
963	+	exception_type_t exception,
964	+	exception_data_t code,
965	+	mach_msg_type_number_t codeCount)
966	+	{
967	+	ppc_thread_state_t state;
968	+	kern_return_t krc;
969	+
970	+	if ((exception == EXC_BAD_ACCESS) && (codeCount >= 2)) {
971	+	if (handle_badaccess(SIGSEGV_FAULT_HANDLER_ARGS))
972	+	return KERN_SUCCESS;
973	+	}
974	+
975	+	// In Mach we do not need to remove the exception handler.
976	+	// If we forward the exception, eventually some exception handler
977	+	// will take care of this exception.
978	+	krc = forward_exception(thread, task, exception, code, codeCount, &ports);
979	+
980	+	return krc;
981	+	}
982	+	#endif
983	+
984	+	#ifdef HAVE_SIGSEGV_RECOVERY
985	+	// Handle bad memory accesses with signal handler
986	+	static void sigsegv_handler(SIGSEGV_FAULT_HANDLER_ARGLIST)
987	+	{
988	+	// Call handler and reinstall the global handler, if required
989	+	if (handle_badaccess(SIGSEGV_FAULT_HANDLER_ARGS)) {
990	+	#if (defined(HAVE_SIGACTION) ? defined(SIGACTION_NEED_REINSTALL) : defined(SIGNAL_NEED_REINSTALL))
991	+	sigsegv_do_install_handler(sig);
992		#endif
993	+	return;
994	+	}
995
996	<	if (!fault_recovered) {
655	<	// FAIL: reinstall default handler for "safe" crash
996	>	// Failure: reinstall default handler for "safe" crash
997		#define FAULT_HANDLER(sig) signal(sig, SIG_DFL);
998	<	SIGSEGV_ALL_SIGNALS
998	>	SIGSEGV_ALL_SIGNALS
999		#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	–	}
1000		}
1001		#endif
1002
#	Line 674 \| Line 1010 \| static bool sigsegv_do_install_handler(i
1010		{
1011		// Setup SIGSEGV handler to process writes to frame buffer
1012		#ifdef HAVE_SIGACTION
1013	<	struct sigaction vosf_sa;
1014	<	sigemptyset(&vosf_sa.sa_mask);
1015	<	vosf_sa.sa_sigaction = sigsegv_handler;
1016	<	vosf_sa.sa_flags = SA_SIGINFO;
1017	<	return (sigaction(sig, &vosf_sa, 0) == 0);
1013	>	struct sigaction sigsegv_sa;
1014	>	sigemptyset(&sigsegv_sa.sa_mask);
1015	>	sigsegv_sa.sa_sigaction = sigsegv_handler;
1016	>	sigsegv_sa.sa_flags = SA_SIGINFO;
1017	>	return (sigaction(sig, &sigsegv_sa, 0) == 0);
1018		#else
1019		return (signal(sig, (signal_handler)sigsegv_handler) != SIG_ERR);
1020		#endif
#	Line 690 \| Line 1026 \| static bool sigsegv_do_install_handler(i
1026		{
1027		// Setup SIGSEGV handler to process writes to frame buffer
1028		#ifdef HAVE_SIGACTION
1029	<	struct sigaction vosf_sa;
1030	<	sigemptyset(&vosf_sa.sa_mask);
1031	<	vosf_sa.sa_handler = (signal_handler)sigsegv_handler;
1029	>	struct sigaction sigsegv_sa;
1030	>	sigemptyset(&sigsegv_sa.sa_mask);
1031	>	sigsegv_sa.sa_handler = (signal_handler)sigsegv_handler;
1032	>	sigsegv_sa.sa_flags = 0;
1033		#if !EMULATED_68K && defined(__NetBSD__)
1034	<	sigaddset(&vosf_sa.sa_mask, SIGALRM);
1035	<	vosf_sa.sa_flags = SA_ONSTACK;
699	<	#else
700	<	vosf_sa.sa_flags = 0;
1034	>	sigaddset(&sigsegv_sa.sa_mask, SIGALRM);
1035	>	sigsegv_sa.sa_flags \|= SA_ONSTACK;
1036		#endif
1037	<	return (sigaction(sig, &vosf_sa, 0) == 0);
1037	>	return (sigaction(sig, &sigsegv_sa, 0) == 0);
1038		#else
1039		return (signal(sig, (signal_handler)sigsegv_handler) != SIG_ERR);
1040		#endif
1041		}
1042		#endif
1043
1044	<	bool sigsegv_install_handler(sigsegv_fault_handler_t handler)
1044	>	#if defined(HAVE_MACH_EXCEPTIONS)
1045	>	static bool sigsegv_do_install_handler(sigsegv_fault_handler_t handler)
1046		{
1047	<	#ifdef HAVE_SIGSEGV_RECOVERY
1047	>	/*
1048	>	* Except for the exception port functions, this should be
1049	>	* pretty much stock Mach. If later you choose to support
1050	>	* other Mach's besides Darwin, just check for __MACH__
1051	>	* here and __APPLE__ where the actual differences are.
1052	>	*/
1053	>	#if defined(__APPLE__) && defined(__MACH__)
1054	>	if (sigsegv_fault_handler != NULL) {
1055	>	sigsegv_fault_handler = handler;
1056	>	return true;
1057	>	}
1058	>
1059	>	kern_return_t krc;
1060	>
1061	>	// create the the exception port
1062	>	krc = mach_port_allocate(mach_task_self(),
1063	>	MACH_PORT_RIGHT_RECEIVE, &_exceptionPort);
1064	>	if (krc != KERN_SUCCESS) {
1065	>	mach_error("mach_port_allocate", krc);
1066	>	return false;
1067	>	}
1068	>
1069	>	// add a port send right
1070	>	krc = mach_port_insert_right(mach_task_self(),
1071	>	_exceptionPort, _exceptionPort,
1072	>	MACH_MSG_TYPE_MAKE_SEND);
1073	>	if (krc != KERN_SUCCESS) {
1074	>	mach_error("mach_port_insert_right", krc);
1075	>	return false;
1076	>	}
1077	>
1078	>	// get the old exception ports
1079	>	ports.maskCount = sizeof (ports.masks) / sizeof (ports.masks[0]);
1080	>	krc = thread_get_exception_ports(mach_thread_self(), EXC_MASK_BAD_ACCESS, ports.masks,
1081	>	&ports.maskCount, ports.handlers, ports.behaviors, ports.flavors);
1082	>	if (krc != KERN_SUCCESS) {
1083	>	mach_error("thread_get_exception_ports", krc);
1084	>	return false;
1085	>	}
1086	>
1087	>	// set the new exception port
1088	>	//
1089	>	// We could have used EXCEPTION_STATE_IDENTITY instead of
1090	>	// EXCEPTION_DEFAULT to get the thread state in the initial
1091	>	// message, but it turns out that in the common case this is not
1092	>	// neccessary. If we need it we can later ask for it from the
1093	>	// suspended thread.
1094	>	//
1095	>	// Even with THREAD_STATE_NONE, Darwin provides the program
1096	>	// counter in the thread state. The comments in the header file
1097	>	// seem to imply that you can count on the GPR's on an exception
1098	>	// as well but just to be safe I use MACHINE_THREAD_STATE because
1099	>	// you have to ask for all of the GPR's anyway just to get the
1100	>	// program counter. In any case because of update effective
1101	>	// address from immediate and update address from effective
1102	>	// addresses of ra and rb modes (as good an name as any for these
1103	>	// addressing modes) used in PPC instructions, you will need the
1104	>	// GPR state anyway.
1105	>	krc = thread_set_exception_ports(mach_thread_self(), EXC_MASK_BAD_ACCESS, _exceptionPort,
1106	>	EXCEPTION_DEFAULT, MACHINE_THREAD_STATE);
1107	>	if (krc != KERN_SUCCESS) {
1108	>	mach_error("thread_set_exception_ports", krc);
1109	>	return false;
1110	>	}
1111	>
1112	>	// create the exception handler thread
1113	>	if (pthread_create(&exc_thread, NULL, &handleExceptions, NULL) != 0) {
1114	>	(void)fprintf(stderr, "creation of exception thread failed\n");
1115	>	return false;
1116	>	}
1117	>
1118	>	// do not care about the exception thread any longer, let is run standalone
1119	>	(void)pthread_detach(exc_thread);
1120	>
1121		sigsegv_fault_handler = handler;
1122	+	return true;
1123	+	#else
1124	+	return false;
1125	+	#endif
1126	+	}
1127	+	#endif
1128	+
1129	+	bool sigsegv_install_handler(sigsegv_fault_handler_t handler)
1130	+	{
1131	+	#if defined(HAVE_SIGSEGV_RECOVERY)
1132		bool success = true;
1133		#define FAULT_HANDLER(sig) success = success && sigsegv_do_install_handler(sig);
1134		SIGSEGV_ALL_SIGNALS
1135		#undef FAULT_HANDLER
1136	+	if (success)
1137	+	sigsegv_fault_handler = handler;
1138		return success;
1139	+	#elif defined(HAVE_MACH_EXCEPTIONS)
1140	+	return sigsegv_do_install_handler(handler);
1141		#else
1142		// FAIL: no siginfo_t nor sigcontext subterfuge is available
1143		return false;
#	Line 728 \| Line 1151 \| bool sigsegv_install_handler(sigsegv_fau
1151
1152		void sigsegv_deinstall_handler(void)
1153		{
1154	+	// We do nothing for Mach exceptions, the thread would need to be
1155	+	// suspended if not already so, and we might mess with other
1156	+	// exception handlers that came after we registered ours. There is
1157	+	// no need to remove the exception handler, in fact this function is
1158	+	// not called anywhere in Basilisk II.
1159		#ifdef HAVE_SIGSEGV_RECOVERY
1160		sigsegv_fault_handler = 0;
1161		#define FAULT_HANDLER(sig) signal(sig, SIG_DFL);
#	Line 738 \| Line 1166 \| void sigsegv_deinstall_handler(void)
1166
1167
1168		/*
741	–	* SIGSEGV ignore state modifier
742	–	*/
743	–
744	–	void sigsegv_set_ignore_state(bool ignore_fault)
745	–	{
746	–	sigsegv_ignore_fault = ignore_fault;
747	–	}
748	–
749	–
750	–	/*
1169		* Set callback function when we cannot handle the fault
1170		*/
1171
#	Line 772 \| Line 1190 \| static int page_size;
1190		static volatile char * page = 0;
1191		static volatile int handler_called = 0;
1192
1193	<	static bool sigsegv_test_handler(sigsegv_address_t fault_address, sigsegv_address_t instruction_address)
1193	>	static sigsegv_return_t sigsegv_test_handler(sigsegv_address_t fault_address, sigsegv_address_t instruction_address)
1194		{
1195		handler_called++;
1196		if ((fault_address - 123) != page)
1197	<	exit(1);
1197	>	exit(10);
1198		if (vm_protect((char *)((unsigned long)fault_address & -page_size), page_size, VM_PAGE_READ \| VM_PAGE_WRITE) != 0)
1199	<	exit(1);
1200	<	return true;
1199	>	exit(11);
1200	>	return SIGSEGV_RETURN_SUCCESS;
1201		}
1202
1203		#ifdef HAVE_SIGSEGV_SKIP_INSTRUCTION
1204	<	static bool sigsegv_insn_handler(sigsegv_address_t fault_address, sigsegv_address_t instruction_address)
1204	>	#ifdef __GNUC__
1205	>	// Code range where we expect the fault to come from
1206	>	static void b_region, e_region;
1207	>	#endif
1208	>
1209	>	static sigsegv_return_t sigsegv_insn_handler(sigsegv_address_t fault_address, sigsegv_address_t instruction_address)
1210		{
1211	<	return false;
1211	>	if (((unsigned long)fault_address - (unsigned long)page) < page_size) {
1212	>	#ifdef __GNUC__
1213	>	// Make sure reported fault instruction address falls into
1214	>	// expected code range
1215	>	if (instruction_address != SIGSEGV_INVALID_PC
1216	>	&& ((instruction_address < (sigsegv_address_t)b_region) \|\|
1217	>	(instruction_address >= (sigsegv_address_t)e_region)))
1218	>	return SIGSEGV_RETURN_FAILURE;
1219	>	#endif
1220	>	return SIGSEGV_RETURN_SKIP_INSTRUCTION;
1221	>	}
1222	>
1223	>	return SIGSEGV_RETURN_FAILURE;
1224		}
1225		#endif
1226
#	Line 796 \| Line 1231 \| int main(void)
1231
1232		page_size = getpagesize();
1233		if ((page = (char *)vm_acquire(page_size)) == VM_MAP_FAILED)
1234	<	return 1;
1234	>	return 2;
1235
1236		if (vm_protect((char *)page, page_size, VM_PAGE_READ) < 0)
1237	<	return 1;
1237	>	return 3;
1238
1239		if (!sigsegv_install_handler(sigsegv_test_handler))
1240	<	return 1;
1240	>	return 4;
1241
1242		page[123] = 45;
1243		page[123] = 45;
1244
1245		if (handler_called != 1)
1246	<	return 1;
1246	>	return 5;
1247
1248		#ifdef HAVE_SIGSEGV_SKIP_INSTRUCTION
1249		if (!sigsegv_install_handler(sigsegv_insn_handler))
1250	<	return 1;
1250	>	return 6;
1251
1252		if (vm_protect((char *)page, page_size, VM_PAGE_READ \| VM_PAGE_WRITE) < 0)
1253	<	return 1;
1253	>	return 7;
1254
1255		for (int i = 0; i < page_size; i++)
1256		page[i] = (i + 1) % page_size;
1257
1258		if (vm_protect((char *)page, page_size, VM_PAGE_NOACCESS) < 0)
1259	<	return 1;
1259	>	return 8;
1260
826	–	sigsegv_set_ignore_state(true);
827	–
1261		#define TEST_SKIP_INSTRUCTION(TYPE) do { \
1262		const unsigned int TAG = 0x12345678; \
1263		TYPE data = ((TYPE )(page + sizeof(TYPE))); \
1264		volatile unsigned int effect = data + TAG; \
1265		if (effect != TAG) \
1266	<	return 1; \
1266	>	return 9; \
1267		} while (0)
1268
1269	+	#ifdef __GNUC__
1270	+	b_region = &&L_b_region;
1271	+	e_region = &&L_e_region;
1272	+	#endif
1273	+	L_b_region:
1274		TEST_SKIP_INSTRUCTION(unsigned char);
1275		TEST_SKIP_INSTRUCTION(unsigned short);
1276		TEST_SKIP_INSTRUCTION(unsigned int);
1277	+	L_e_region:
1278		#endif
1279
1280		vm_exit();

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Comparing BasiliskII/src/Unix/sigsegv.cpp (file contents): Revision 1.21 by gbeauche, 2002-10-03T15:49:14Z vs. Revision 1.29 by gbeauche, 2003-10-13T19:43:09Z

Diff Legend

Comparing BasiliskII/src/Unix/sigsegv.cpp (file contents):
Revision 1.21 by gbeauche, 2002-10-03T15:49:14Z vs.
Revision 1.29 by gbeauche, 2003-10-13T19:43:09Z