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root/cebix/BasiliskII/src/Unix/sigsegv.cpp

Comparing BasiliskII/src/Unix/sigsegv.cpp (file contents):
Revision 1.2 by gbeauche, 2001-05-21T03:21:54Z vs.
Revision 1.18 by gbeauche, 2002-05-20T18:12:01Z

#	Line 4 | Line 4
4		*  Derived from Bruno Haible's work on his SIGSEGV library for clisp
5		*  <http://clisp.sourceforge.net/>
6		*
7	<	*  Basilisk II (C) 1997-2001 Christian Bauer
7	>	*  Basilisk II (C) 1997-2002 Christian Bauer
8		*
9		*  This program is free software; you can redistribute it and/or modify
10		*  it under the terms of the GNU General Public License as published by
#	Line 40 | Line 40
40		// Type of the system signal handler
41		typedef RETSIGTYPE (*signal_handler)(int);
42
43	+	// Is the fault to be ignored?
44	+	static bool sigsegv_ignore_fault = false;
45	+
46		// User's SIGSEGV handler
47	<	static sigsegv_handler_t sigsegv_user_handler = 0;
47	>	static sigsegv_fault_handler_t sigsegv_fault_handler = 0;
48	>
49	>	// Function called to dump state if we can't handle the fault
50	>	static sigsegv_state_dumper_t sigsegv_state_dumper = 0;
51
52		// Actual SIGSEGV handler installer
53		static bool sigsegv_do_install_handler(int sig);
54
55
56		/*
57	+	*  Instruction decoding aids
58	+	*/
59	+
60	+	// Transfer type
61	+	enum transfer_type_t {
62	+	TYPE_UNKNOWN,
63	+	TYPE_LOAD,
64	+	TYPE_STORE
65	+	};
66	+
67	+	// Transfer size
68	+	enum transfer_size_t {
69	+	SIZE_UNKNOWN,
70	+	SIZE_BYTE,
71	+	SIZE_WORD,
72	+	SIZE_LONG
73	+	};
74	+
75	+	#if (defined(powerpc) || defined(__powerpc__) || defined(__ppc__))
76	+	// Addressing mode
77	+	enum addressing_mode_t {
78	+	MODE_UNKNOWN,
79	+	MODE_NORM,
80	+	MODE_U,
81	+	MODE_X,
82	+	MODE_UX
83	+	};
84	+
85	+	// Decoded instruction
86	+	struct instruction_t {
87	+	transfer_type_t         transfer_type;
88	+	transfer_size_t         transfer_size;
89	+	addressing_mode_t       addr_mode;
90	+	unsigned int            addr;
91	+	char                            ra, rd;
92	+	};
93	+
94	+	static void powerpc_decode_instruction(instruction_t *instruction, unsigned int nip, unsigned int * gpr)
95	+	{
96	+	// Get opcode and divide into fields
97	+	unsigned int opcode = *((unsigned int *)nip);
98	+	unsigned int primop = opcode >> 26;
99	+	unsigned int exop = (opcode >> 1) & 0x3ff;
100	+	unsigned int ra = (opcode >> 16) & 0x1f;
101	+	unsigned int rb = (opcode >> 11) & 0x1f;
102	+	unsigned int rd = (opcode >> 21) & 0x1f;
103	+	signed int imm = (signed short)(opcode & 0xffff);
104	+
105	+	// Analyze opcode
106	+	transfer_type_t transfer_type = TYPE_UNKNOWN;
107	+	transfer_size_t transfer_size = SIZE_UNKNOWN;
108	+	addressing_mode_t addr_mode = MODE_UNKNOWN;
109	+	switch (primop) {
110	+	case 31:
111	+	switch (exop) {
112	+	case 23:        // lwzx
113	+	transfer_type = TYPE_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_X; break;
114	+	case 55:        // lwzux
115	+	transfer_type = TYPE_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_UX; break;
116	+	case 87:        // lbzx
117	+	transfer_type = TYPE_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_X; break;
118	+	case 119:       // lbzux
119	+	transfer_type = TYPE_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_UX; break;
120	+	case 151:       // stwx
121	+	transfer_type = TYPE_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_X; break;
122	+	case 183:       // stwux
123	+	transfer_type = TYPE_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_UX; break;
124	+	case 215:       // stbx
125	+	transfer_type = TYPE_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_X; break;
126	+	case 247:       // stbux
127	+	transfer_type = TYPE_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_UX; break;
128	+	case 279:       // lhzx
129	+	transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_X; break;
130	+	case 311:       // lhzux
131	+	transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_UX; break;
132	+	case 343:       // lhax
133	+	transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_X; break;
134	+	case 375:       // lhaux
135	+	transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_UX; break;
136	+	case 407:       // sthx
137	+	transfer_type = TYPE_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_X; break;
138	+	case 439:       // sthux
139	+	transfer_type = TYPE_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_UX; break;
140	+	}
141	+	break;
142	+
143	+	case 32:        // lwz
144	+	transfer_type = TYPE_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_NORM; break;
145	+	case 33:        // lwzu
146	+	transfer_type = TYPE_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_U; break;
147	+	case 34:        // lbz
148	+	transfer_type = TYPE_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_NORM; break;
149	+	case 35:        // lbzu
150	+	transfer_type = TYPE_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_U; break;
151	+	case 36:        // stw
152	+	transfer_type = TYPE_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_NORM; break;
153	+	case 37:        // stwu
154	+	transfer_type = TYPE_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_U; break;
155	+	case 38:        // stb
156	+	transfer_type = TYPE_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_NORM; break;
157	+	case 39:        // stbu
158	+	transfer_type = TYPE_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_U; break;
159	+	case 40:        // lhz
160	+	transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_NORM; break;
161	+	case 41:        // lhzu
162	+	transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_U; break;
163	+	case 42:        // lha
164	+	transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_NORM; break;
165	+	case 43:        // lhau
166	+	transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_U; break;
167	+	case 44:        // sth
168	+	transfer_type = TYPE_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_NORM; break;
169	+	case 45:        // sthu
170	+	transfer_type = TYPE_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_U; break;
171	+	}
172	+
173	+	// Calculate effective address
174	+	unsigned int addr = 0;
175	+	switch (addr_mode) {
176	+	case MODE_X:
177	+	case MODE_UX:
178	+	if (ra == 0)
179	+	addr = gpr[rb];
180	+	else
181	+	addr = gpr[ra] + gpr[rb];
182	+	break;
183	+	case MODE_NORM:
184	+	case MODE_U:
185	+	if (ra == 0)
186	+	addr = (signed int)(signed short)imm;
187	+	else
188	+	addr = gpr[ra] + (signed int)(signed short)imm;
189	+	break;
190	+	default:
191	+	break;
192	+	}
193	+
194	+	// Commit decoded instruction
195	+	instruction->addr = addr;
196	+	instruction->addr_mode = addr_mode;
197	+	instruction->transfer_type = transfer_type;
198	+	instruction->transfer_size = transfer_size;
199	+	instruction->ra = ra;
200	+	instruction->rd = rd;
201	+	}
202	+	#endif
203	+
204	+
205	+	/*
206		*  OS-dependant SIGSEGV signals support section
207		*/
208
209		#if HAVE_SIGINFO_T
210		// Generic extended signal handler
211	+	#if defined(__NetBSD__) || defined(__FreeBSD__)
212	+	#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGBUS)
213	+	#else
214		#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGSEGV)
215	<	#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, siginfo_t *sip, void *
215	>	#endif
216	>	#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, siginfo_t *sip, void *scp
217		#define SIGSEGV_FAULT_ADDRESS                   sip->si_addr
218	+	#if (defined(i386) || defined(__i386__))
219	+	#define SIGSEGV_FAULT_INSTRUCTION               (((struct sigcontext *)scp)->sc_eip)
220	+	#define SIGSEGV_REGISTER_FILE                   ((unsigned int *)&(((struct sigcontext *)scp)->sc_edi)) /* EDI is the first GPR (even below EIP) in sigcontext */
221	+	/* (gb) Disable because this would hang configure script for some reason
222	+	* though standalone testing gets it right. Any idea why?
223	+	#define SIGSEGV_SKIP_INSTRUCTION                ix86_skip_instruction
224	+	*/
225	+	#endif
226	+	#if defined(__linux__)
227	+	#if (defined(i386) || defined(__i386__))
228	+	#include <sys/ucontext.h>
229	+	#define SIGSEGV_CONTEXT_REGS                    (((ucontext_t *)scp)->uc_mcontext.gregs)
230	+	#define SIGSEGV_FAULT_INSTRUCTION               SIGSEGV_CONTEXT_REGS[14] /* should use REG_EIP instead */
231	+	#define SIGSEGV_REGISTER_FILE                   (unsigned int *)SIGSEGV_CONTEXT_REGS
232	+	#define SIGSEGV_SKIP_INSTRUCTION                ix86_skip_instruction
233	+	#endif
234	+	#if (defined(ia64) || defined(__ia64__))
235	+	#define SIGSEGV_FAULT_INSTRUCTION               (((struct sigcontext *)scp)->sc_ip & ~0x3ULL) /* slot number is in bits 0 and 1 */
236	+	#endif
237	+	#if (defined(powerpc) || defined(__powerpc__))
238	+	#include <sys/ucontext.h>
239	+	#define SIGSEGV_CONTEXT_REGS                    (((ucontext_t *)scp)->uc_mcontext.regs)
240	+	#define SIGSEGV_FAULT_INSTRUCTION               (SIGSEGV_CONTEXT_REGS->nip)
241	+	#define SIGSEGV_REGISTER_FILE                   (unsigned int *)&SIGSEGV_CONTEXT_REGS->nip, (unsigned int *)(SIGSEGV_CONTEXT_REGS->gpr)
242	+	#define SIGSEGV_SKIP_INSTRUCTION                powerpc_skip_instruction
243	+	#endif
244	+	#endif
245		#endif
246
247		#if HAVE_SIGCONTEXT_SUBTERFUGE
#	Line 67 | Line 253 | static bool sigsegv_do_install_handler(i
253		#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, struct sigcontext scs
254		#define SIGSEGV_FAULT_ADDRESS                   scs.cr2
255		#define SIGSEGV_FAULT_INSTRUCTION               scs.eip
256	+	#define SIGSEGV_REGISTER_FILE                   (unsigned int *)(&scs)
257	+	#define SIGSEGV_SKIP_INSTRUCTION                ix86_skip_instruction
258		#endif
259		#if (defined(sparc) || defined(__sparc__))
260		#include <asm/sigcontext.h>
261	<	#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext* scp, char* addr
261	>	#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp, char *addr
262		#define SIGSEGV_FAULT_ADDRESS                   addr
263		#endif
264		#if (defined(powerpc) || defined(__powerpc__))
265		#include <asm/sigcontext.h>
266	<	#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, struct sigcontext* scp
266	>	#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, struct sigcontext *scp
267		#define SIGSEGV_FAULT_ADDRESS                   scp->regs->dar
268		#define SIGSEGV_FAULT_INSTRUCTION               scp->regs->nip
269	+	#define SIGSEGV_REGISTER_FILE                   (unsigned int *)&scp->regs->nip, (unsigned int *)(scp->regs->gpr)
270	+	#define SIGSEGV_SKIP_INSTRUCTION                powerpc_skip_instruction
271	+	#endif
272	+	#if (defined(alpha) || defined(__alpha__))
273	+	#include <asm/sigcontext.h>
274	+	#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
275	+	#define SIGSEGV_FAULT_ADDRESS                   get_fault_address(scp)
276	+	#define SIGSEGV_FAULT_INSTRUCTION               scp->sc_pc
277	+
278	+	// From Boehm's GC 6.0alpha8
279	+	static sigsegv_address_t get_fault_address(struct sigcontext *scp)
280	+	{
281	+	unsigned int instruction = *((unsigned int *)(scp->sc_pc));
282	+	unsigned long fault_address = scp->sc_regs[(instruction >> 16) & 0x1f];
283	+	fault_address += (signed long)(signed short)(instruction & 0xffff);
284	+	return (sigsegv_address_t)fault_address;
285	+	}
286		#endif
287		#endif
288
289		// Irix 5 or 6 on MIPS
290		#if (defined(sgi) || defined(__sgi)) && (defined(SYSTYPE_SVR4) || defined(__SYSTYPE_SVR4))
291	+	#include <ucontext.h>
292		#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
293		#define SIGSEGV_FAULT_ADDRESS                   scp->sc_badvaddr
294		#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGSEGV)
295		#endif
296
297	+	// HP-UX
298	+	#if (defined(hpux) || defined(__hpux__))
299	+	#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
300	+	#define SIGSEGV_FAULT_ADDRESS                   scp->sc_sl.sl_ss.ss_narrow.ss_cr21
301	+	#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGSEGV) FAULT_HANDLER(SIGBUS)
302	+	#endif
303	+
304		// OSF/1 on Alpha
305		#if defined(__osf__)
306	+	#include <ucontext.h>
307		#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
308		#define SIGSEGV_FAULT_ADDRESS                   scp->sc_traparg_a0
309		#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGSEGV)
#	Line 107 | Line 321 | static bool sigsegv_do_install_handler(i
321		#if (defined(m68k) || defined(__m68k__))
322		#include <m68k/frame.h>
323		#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
324	<	#define SIGSEGV_FAULT_ADDRESS                   ({                                                                                                                              \
111	<	struct sigstate {                                                                                                                                                                       \
112	<	int ss_flags;                                                                                                                                                                   \
113	<	struct frame ss_frame;                                                                                                                                                  \
114	<	};                                                                                                                                                                                                      \
115	<	struct sigstate *state = (struct sigstate *)scp->sc_ap;                                                                                         \
116	<	char *fault_addr;                                                                                                                                                                       \
117	<	switch (state->ss_frame.f_format) {                                                                                                                                     \
118	<	case 7:         /* 68040 access error */                                                                                                                                \
119	<	/* "code" is sometimes unreliable (i.e. contains NULL or a bogus address), reason unknown */    \
120	<	fault_addr = state->ss_frame.f_fmt7.f_fa;                                                                                                               \
121	<	break;                                                                                                                                                                                  \
122	<	default:                                                                                                                                                                                        \
123	<	fault_addr = (char *)code;                                                                                                                                              \
124	<	break;                                                                                                                                                                                  \
125	<	}                                                                                                                                                                                                       \
126	<	fault_addr;                                                                                                                                                                                     \
127	<	})
324	>	#define SIGSEGV_FAULT_ADDRESS                   get_fault_address(scp)
325		#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGSEGV)
326	+
327	+	// Use decoding scheme from BasiliskII/m68k native
328	+	static sigsegv_address_t get_fault_address(struct sigcontext *scp)
329	+	{
330	+	struct sigstate {
331	+	int ss_flags;
332	+	struct frame ss_frame;
333	+	};
334	+	struct sigstate *state = (struct sigstate *)scp->sc_ap;
335	+	char *fault_addr;
336	+	switch (state->ss_frame.f_format) {
337	+	case 7:         /* 68040 access error */
338	+	/* "code" is sometimes unreliable (i.e. contains NULL or a bogus address), reason unknown */
339	+	fault_addr = state->ss_frame.f_fmt7.f_fa;
340	+	break;
341	+	default:
342	+	fault_addr = (char *)code;
343	+	break;
344	+	}
345	+	return (sigsegv_address_t)fault_addr;
346	+	}
347		#else
348		#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, void *scp, char *addr
349		#define SIGSEGV_FAULT_ADDRESS                   addr
350		#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGBUS)
351		#endif
352		#endif
353	+
354	+	// MacOS X
355	+	#if defined(__APPLE__) && defined(__MACH__)
356	+	#if (defined(ppc) || defined(__ppc__))
357	+	#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
358	+	#define SIGSEGV_FAULT_ADDRESS                   get_fault_address(scp)
359	+	#define SIGSEGV_FAULT_INSTRUCTION               scp->sc_ir
360	+	#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGBUS)
361	+	#define SIGSEGV_REGISTER_FILE                   (unsigned int *)&scp->sc_ir, &((unsigned int *) scp->sc_regs)[2]
362	+	#define SIGSEGV_SKIP_INSTRUCTION                powerpc_skip_instruction
363	+
364	+	// Use decoding scheme from SheepShaver
365	+	static sigsegv_address_t get_fault_address(struct sigcontext *scp)
366	+	{
367	+	unsigned int   nip = (unsigned int) scp->sc_ir;
368	+	unsigned int * gpr = &((unsigned int *) scp->sc_regs)[2];
369	+	instruction_t  instr;
370	+
371	+	powerpc_decode_instruction(&instr, nip, gpr);
372	+	return (sigsegv_address_t)instr.addr;
373	+	}
374	+	#endif
375	+	#endif
376	+	#endif
377	+
378	+
379	+	/*
380	+	*  Instruction skipping
381	+	*/
382	+
383	+	#ifdef HAVE_SIGSEGV_SKIP_INSTRUCTION
384	+	// Decode and skip X86 instruction
385	+	#if (defined(i386) || defined(__i386__))
386	+	#if defined(__linux__)
387	+	enum {
388	+	X86_REG_EIP = 14,
389	+	X86_REG_EAX = 11,
390	+	X86_REG_ECX = 10,
391	+	X86_REG_EDX = 9,
392	+	X86_REG_EBX = 8,
393	+	X86_REG_ESP = 7,
394	+	X86_REG_EBP = 6,
395	+	X86_REG_ESI = 5,
396	+	X86_REG_EDI = 4
397	+	};
398	+	#endif
399	+	#if defined(__NetBSD__) || defined(__FreeBSD__)
400	+	enum {
401	+	X86_REG_EIP = 10,
402	+	X86_REG_EAX = 7,
403	+	X86_REG_ECX = 6,
404	+	X86_REG_EDX = 5,
405	+	X86_REG_EBX = 4,
406	+	X86_REG_ESP = 13,
407	+	X86_REG_EBP = 2,
408	+	X86_REG_ESI = 1,
409	+	X86_REG_EDI = 0
410	+	};
411	+	#endif
412	+	// FIXME: this is partly redundant with the instruction decoding phase
413	+	// to discover transfer type and register number
414	+	static inline int ix86_step_over_modrm(unsigned char * p)
415	+	{
416	+	int mod = (p[0] >> 6) & 3;
417	+	int rm = p[0] & 7;
418	+	int offset = 0;
419	+
420	+	// ModR/M Byte
421	+	switch (mod) {
422	+	case 0: // [reg]
423	+	if (rm == 5) return 4; // disp32
424	+	break;
425	+	case 1: // disp8[reg]
426	+	offset = 1;
427	+	break;
428	+	case 2: // disp32[reg]
429	+	offset = 4;
430	+	break;
431	+	case 3: // register
432	+	return 0;
433	+	}
434	+
435	+	// SIB Byte
436	+	if (rm == 4) {
437	+	if (mod == 0 && (p[1] & 7) == 5)
438	+	offset = 5; // disp32[index]
439	+	else
440	+	offset++;
441	+	}
442	+
443	+	return offset;
444	+	}
445	+
446	+	static bool ix86_skip_instruction(unsigned int * regs)
447	+	{
448	+	unsigned char * eip = (unsigned char *)regs[X86_REG_EIP];
449	+
450	+	if (eip == 0)
451	+	return false;
452	+
453	+	transfer_type_t transfer_type = TYPE_UNKNOWN;
454	+	transfer_size_t transfer_size = SIZE_LONG;
455	+
456	+	int reg = -1;
457	+	int len = 0;
458	+
459	+	// Operand size prefix
460	+	if (*eip == 0x66) {
461	+	eip++;
462	+	len++;
463	+	transfer_size = SIZE_WORD;
464	+	}
465	+
466	+	// Decode instruction
467	+	switch (eip[0]) {
468	+	case 0x0f:
469	+	switch (eip[1]) {
470	+	case 0xb6: // MOVZX r32, r/m8
471	+	case 0xb7: // MOVZX r32, r/m16
472	+	switch (eip[2] & 0xc0) {
473	+	case 0x80:
474	+	reg = (eip[2] >> 3) & 7;
475	+	transfer_type = TYPE_LOAD;
476	+	break;
477	+	case 0x40:
478	+	reg = (eip[2] >> 3) & 7;
479	+	transfer_type = TYPE_LOAD;
480	+	break;
481	+	case 0x00:
482	+	reg = (eip[2] >> 3) & 7;
483	+	transfer_type = TYPE_LOAD;
484	+	break;
485	+	}
486	+	len += 3 + ix86_step_over_modrm(eip + 2);
487	+	break;
488	+	}
489	+	break;
490	+	case 0x8a: // MOV r8, r/m8
491	+	transfer_size = SIZE_BYTE;
492	+	case 0x8b: // MOV r32, r/m32 (or 16-bit operation)
493	+	switch (eip[1] & 0xc0) {
494	+	case 0x80:
495	+	reg = (eip[1] >> 3) & 7;
496	+	transfer_type = TYPE_LOAD;
497	+	break;
498	+	case 0x40:
499	+	reg = (eip[1] >> 3) & 7;
500	+	transfer_type = TYPE_LOAD;
501	+	break;
502	+	case 0x00:
503	+	reg = (eip[1] >> 3) & 7;
504	+	transfer_type = TYPE_LOAD;
505	+	break;
506	+	}
507	+	len += 2 + ix86_step_over_modrm(eip + 1);
508	+	break;
509	+	case 0x88: // MOV r/m8, r8
510	+	transfer_size = SIZE_BYTE;
511	+	case 0x89: // MOV r/m32, r32 (or 16-bit operation)
512	+	switch (eip[1] & 0xc0) {
513	+	case 0x80:
514	+	reg = (eip[1] >> 3) & 7;
515	+	transfer_type = TYPE_STORE;
516	+	break;
517	+	case 0x40:
518	+	reg = (eip[1] >> 3) & 7;
519	+	transfer_type = TYPE_STORE;
520	+	break;
521	+	case 0x00:
522	+	reg = (eip[1] >> 3) & 7;
523	+	transfer_type = TYPE_STORE;
524	+	break;
525	+	}
526	+	len += 2 + ix86_step_over_modrm(eip + 1);
527	+	break;
528	+	}
529	+
530	+	if (transfer_type == TYPE_UNKNOWN) {
531	+	// Unknown machine code, let it crash. Then patch the decoder
532	+	return false;
533	+	}
534	+
535	+	if (transfer_type == TYPE_LOAD && reg != -1) {
536	+	static const int x86_reg_map[8] = {
537	+	X86_REG_EAX, X86_REG_ECX, X86_REG_EDX, X86_REG_EBX,
538	+	X86_REG_ESP, X86_REG_EBP, X86_REG_ESI, X86_REG_EDI
539	+	};
540	+
541	+	if (reg < 0 || reg >= 8)
542	+	return false;
543	+
544	+	int rloc = x86_reg_map[reg];
545	+	switch (transfer_size) {
546	+	case SIZE_BYTE:
547	+	regs[rloc] = (regs[rloc] & ~0xff);
548	+	break;
549	+	case SIZE_WORD:
550	+	regs[rloc] = (regs[rloc] & ~0xffff);
551	+	break;
552	+	case SIZE_LONG:
553	+	regs[rloc] = 0;
554	+	break;
555	+	}
556	+	}
557	+
558	+	#if DEBUG
559	+	printf("%08x: %s %s access", regs[X86_REG_EIP],
560	+	transfer_size == SIZE_BYTE ? "byte" : transfer_size == SIZE_WORD ? "word" : "long",
561	+	transfer_type == TYPE_LOAD ? "read" : "write");
562	+
563	+	if (reg != -1) {
564	+	static const char * x86_reg_str_map[8] = {
565	+	"eax", "ecx", "edx", "ebx",
566	+	"esp", "ebp", "esi", "edi"
567	+	};
568	+	printf(" %s register %%%s", transfer_type == TYPE_LOAD ? "to" : "from", x86_reg_str_map[reg]);
569	+	}
570	+	printf(", %d bytes instruction\n", len);
571	+	#endif
572	+
573	+	regs[X86_REG_EIP] += len;
574	+	return true;
575	+	}
576	+	#endif
577	+
578	+	// Decode and skip PPC instruction
579	+	#if (defined(powerpc) || defined(__powerpc__) || defined(__ppc__))
580	+	static bool powerpc_skip_instruction(unsigned int * nip_p, unsigned int * regs)
581	+	{
582	+	instruction_t instr;
583	+	powerpc_decode_instruction(&instr, *nip_p, regs);
584	+
585	+	if (instr.transfer_type == TYPE_UNKNOWN) {
586	+	// Unknown machine code, let it crash. Then patch the decoder
587	+	return false;
588	+	}
589	+
590	+	#if DEBUG
591	+	printf("%08x: %s %s access", *nip_p,
592	+	instr.transfer_size == SIZE_BYTE ? "byte" : instr.transfer_size == SIZE_WORD ? "word" : "long",
593	+	instr.transfer_type == TYPE_LOAD ? "read" : "write");
594	+
595	+	if (instr.addr_mode == MODE_U || instr.addr_mode == MODE_UX)
596	+	printf(" r%d (ra = %08x)\n", instr.ra, instr.addr);
597	+	if (instr.transfer_type == TYPE_LOAD)
598	+	printf(" r%d (rd = 0)\n", instr.rd);
599	+	#endif
600	+
601	+	if (instr.addr_mode == MODE_U || instr.addr_mode == MODE_UX)
602	+	regs[instr.ra] = instr.addr;
603	+	if (instr.transfer_type == TYPE_LOAD)
604	+	regs[instr.rd] = 0;
605	+
606	+	*nip_p += 4;
607	+	return true;
608	+	}
609	+	#endif
610		#endif
611
612		// Fallbacks
#	Line 152 | Line 627 | static bool sigsegv_do_install_handler(i
627		#ifdef HAVE_SIGSEGV_RECOVERY
628		static void sigsegv_handler(SIGSEGV_FAULT_HANDLER_ARGLIST)
629		{
630	+	sigsegv_address_t fault_address = (sigsegv_address_t)SIGSEGV_FAULT_ADDRESS;
631	+	sigsegv_address_t fault_instruction = (sigsegv_address_t)SIGSEGV_FAULT_INSTRUCTION;
632	+	bool fault_recovered = false;
633	+
634		// Call user's handler and reinstall the global handler, if required
635	<	if (sigsegv_user_handler((sigsegv_address_t)SIGSEGV_FAULT_ADDRESS, (sigsegv_address_t)SIGSEGV_FAULT_INSTRUCTION)) {
635	>	if (sigsegv_fault_handler(fault_address, fault_instruction)) {
636		#if (defined(HAVE_SIGACTION) ? defined(SIGACTION_NEED_REINSTALL) : defined(SIGNAL_NEED_REINSTALL))
637		sigsegv_do_install_handler(sig);
638		#endif
639	+	fault_recovered = true;
640	+	}
641	+	#if HAVE_SIGSEGV_SKIP_INSTRUCTION
642	+	else if (sigsegv_ignore_fault) {
643	+	// Call the instruction skipper with the register file available
644	+	if (SIGSEGV_SKIP_INSTRUCTION(SIGSEGV_REGISTER_FILE))
645	+	fault_recovered = true;
646		}
647	<	else {
647	>	#endif
648	>
649	>	if (!fault_recovered) {
650		// FAIL: reinstall default handler for "safe" crash
651		#define FAULT_HANDLER(sig) signal(sig, SIG_DFL);
652		SIGSEGV_ALL_SIGNALS
653		#undef FAULT_HANDLER
654	+
655	+	// We can't do anything with the fault_address, dump state?
656	+	if (sigsegv_state_dumper != 0)
657	+	sigsegv_state_dumper(fault_address, fault_instruction);
658		}
659		}
660		#endif
#	Line 209 | Line 701 | static bool sigsegv_do_install_handler(i
701		}
702		#endif
703
704	<	bool sigsegv_install_handler(sigsegv_handler_t handler)
704	>	bool sigsegv_install_handler(sigsegv_fault_handler_t handler)
705		{
706		#ifdef HAVE_SIGSEGV_RECOVERY
707	<	sigsegv_user_handler = handler;
707	>	sigsegv_fault_handler = handler;
708		bool success = true;
709		#define FAULT_HANDLER(sig) success = success && sigsegv_do_install_handler(sig);
710		SIGSEGV_ALL_SIGNALS
#	Line 232 | Line 724 | bool sigsegv_install_handler(sigsegv_han
724		void sigsegv_deinstall_handler(void)
725		{
726		#ifdef HAVE_SIGSEGV_RECOVERY
727	<	sigsegv_user_handler = 0;
727	>	sigsegv_fault_handler = 0;
728		#define FAULT_HANDLER(sig) signal(sig, SIG_DFL);
729		SIGSEGV_ALL_SIGNALS
730		#undef FAULT_HANDLER
731		#endif
732		}
733
734	+
735	+	/*
736	+	*  SIGSEGV ignore state modifier
737	+	*/
738	+
739	+	void sigsegv_set_ignore_state(bool ignore_fault)
740	+	{
741	+	sigsegv_ignore_fault = ignore_fault;
742	+	}
743	+
744	+
745	+	/*
746	+	*  Set callback function when we cannot handle the fault
747	+	*/
748	+
749	+	void sigsegv_set_dump_state(sigsegv_state_dumper_t handler)
750	+	{
751	+	sigsegv_state_dumper = handler;
752	+	}
753	+
754	+
755		/*
756		*  Test program used for configure/test
757		*/
758
759	<	#ifdef CONFIGURE_TEST
759	>	#ifdef CONFIGURE_TEST_SIGSEGV_RECOVERY
760		#include <stdio.h>
761		#include <stdlib.h>
249	–	#include <unistd.h>
762		#include <fcntl.h>
763		#include <sys/mman.h>
764	+	#include "vm_alloc.h"
765
253	–	static caddr_t page = 0;
766		static int page_size;
767	<	static int handler_called = 0;
767	>	static volatile char * page = 0;
768	>	static volatile int handler_called = 0;
769
770		static bool sigsegv_test_handler(sigsegv_address_t fault_address, sigsegv_address_t instruction_address)
771		{
772		handler_called++;
773		if ((fault_address - 123) != page)
774		exit(1);
775	<	if (mprotect((caddr_t)((unsigned long)fault_address & -page_size), page_size, PROT_READ | PROT_WRITE) != 0)
775	>	if (vm_protect((char *)((unsigned long)fault_address & -page_size), page_size, VM_PAGE_READ | VM_PAGE_WRITE) != 0)
776		exit(1);
777		return true;
778		}
779
780	+	#ifdef HAVE_SIGSEGV_SKIP_INSTRUCTION
781	+	static bool sigsegv_insn_handler(sigsegv_address_t fault_address, sigsegv_address_t instruction_address)
782	+	{
783	+	return false;
784	+	}
785	+	#endif
786	+
787		int main(void)
788		{
789	<	int zero_fd = open("/dev/zero", O_RDWR);
270	<	if (zero_fd < 0)
789	>	if (vm_init() < 0)
790		return 1;
791
792		page_size = getpagesize();
793	<	page = (caddr_t)mmap(0, page_size, PROT_READ, MAP_PRIVATE, zero_fd, 0);
794	<	if (page == MAP_FAILED)
793	>	if ((page = (char *)vm_acquire(page_size)) == VM_MAP_FAILED)
794	>	return 1;
795	>
796	>	if (vm_protect((char *)page, page_size, VM_PAGE_READ) < 0)
797		return 1;
798
799		if (!sigsegv_install_handler(sigsegv_test_handler))
#	Line 284 | Line 805 | int main(void)
805		if (handler_called != 1)
806		return 1;
807
808	+	#ifdef HAVE_SIGSEGV_SKIP_INSTRUCTION
809	+	if (!sigsegv_install_handler(sigsegv_insn_handler))
810	+	return 1;
811	+
812	+	if (vm_protect((char *)page, page_size, VM_PAGE_READ | VM_PAGE_WRITE) < 0)
813	+	return 1;
814	+
815	+	for (int i = 0; i < page_size; i++)
816	+	page[i] = (i + 1) % page_size;
817	+
818	+	if (vm_protect((char *)page, page_size, VM_PAGE_NOACCESS) < 0)
819	+	return 1;
820	+
821	+	sigsegv_set_ignore_state(true);
822	+
823	+	#define TEST_SKIP_INSTRUCTION(TYPE) do {                                \
824	+	const unsigned int TAG = 0x12345678;                    \
825	+	TYPE data = *((TYPE *)(page + sizeof(TYPE)));   \
826	+	volatile unsigned int effect = data + TAG;              \
827	+	if (effect != TAG)                                                              \
828	+	return 1;                                                                       \
829	+	} while (0)
830	+
831	+	TEST_SKIP_INSTRUCTION(unsigned char);
832	+	TEST_SKIP_INSTRUCTION(unsigned short);
833	+	TEST_SKIP_INSTRUCTION(unsigned int);
834	+	#endif
835	+
836	+	vm_exit();
837		return 0;
838		}
839		#endif

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