ViewVC Help

View File | Revision Log | Show Annotations | Revision Graph | Root Listing

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 1.21 by gbeauche, 2002-10-03T15:49:14Z

#	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(__NetBSD__) || defined(__FreeBSD__)
219	+	#if (defined(i386) || defined(__i386__))
220	+	#define SIGSEGV_FAULT_INSTRUCTION               (((struct sigcontext *)scp)->sc_eip)
221	+	#define SIGSEGV_REGISTER_FILE                   ((unsigned int *)&(((struct sigcontext *)scp)->sc_edi)) /* EDI is the first GPR (even below EIP) in sigcontext */
222	+	#define SIGSEGV_SKIP_INSTRUCTION                ix86_skip_instruction
223	+	#endif
224	+	#endif
225	+	#if defined(__linux__)
226	+	#if (defined(i386) || defined(__i386__))
227	+	#include <sys/ucontext.h>
228	+	#define SIGSEGV_CONTEXT_REGS                    (((ucontext_t *)scp)->uc_mcontext.gregs)
229	+	#define SIGSEGV_FAULT_INSTRUCTION               SIGSEGV_CONTEXT_REGS[14] /* should use REG_EIP instead */
230	+	#define SIGSEGV_REGISTER_FILE                   (unsigned int *)SIGSEGV_CONTEXT_REGS
231	+	#define SIGSEGV_SKIP_INSTRUCTION                ix86_skip_instruction
232	+	#endif
233	+	#if (defined(x86_64) || defined(__x86_64__))
234	+	#include <sys/ucontext.h>
235	+	#define SIGSEGV_CONTEXT_REGS                    (((ucontext_t *)scp)->uc_mcontext.gregs)
236	+	#define SIGSEGV_FAULT_INSTRUCTION               SIGSEGV_CONTEXT_REGS[16] /* should use REG_RIP instead */
237	+	#define SIGSEGV_REGISTER_FILE                   (unsigned long *)SIGSEGV_CONTEXT_REGS
238	+	#endif
239	+	#if (defined(ia64) || defined(__ia64__))
240	+	#define SIGSEGV_FAULT_INSTRUCTION               (((struct sigcontext *)scp)->sc_ip & ~0x3ULL) /* slot number is in bits 0 and 1 */
241	+	#endif
242	+	#if (defined(powerpc) || defined(__powerpc__))
243	+	#include <sys/ucontext.h>
244	+	#define SIGSEGV_CONTEXT_REGS                    (((ucontext_t *)scp)->uc_mcontext.regs)
245	+	#define SIGSEGV_FAULT_INSTRUCTION               (SIGSEGV_CONTEXT_REGS->nip)
246	+	#define SIGSEGV_REGISTER_FILE                   (unsigned int *)&SIGSEGV_CONTEXT_REGS->nip, (unsigned int *)(SIGSEGV_CONTEXT_REGS->gpr)
247	+	#define SIGSEGV_SKIP_INSTRUCTION                powerpc_skip_instruction
248	+	#endif
249	+	#endif
250		#endif
251
252		#if HAVE_SIGCONTEXT_SUBTERFUGE
#	Line 67 | Line 258 | static bool sigsegv_do_install_handler(i
258		#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, struct sigcontext scs
259		#define SIGSEGV_FAULT_ADDRESS                   scs.cr2
260		#define SIGSEGV_FAULT_INSTRUCTION               scs.eip
261	+	#define SIGSEGV_REGISTER_FILE                   (unsigned int *)(&scs)
262	+	#define SIGSEGV_SKIP_INSTRUCTION                ix86_skip_instruction
263		#endif
264		#if (defined(sparc) || defined(__sparc__))
265		#include <asm/sigcontext.h>
266	<	#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext* scp, char* addr
266	>	#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp, char *addr
267		#define SIGSEGV_FAULT_ADDRESS                   addr
268		#endif
269		#if (defined(powerpc) || defined(__powerpc__))
270		#include <asm/sigcontext.h>
271	<	#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, struct sigcontext* scp
271	>	#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, struct sigcontext *scp
272		#define SIGSEGV_FAULT_ADDRESS                   scp->regs->dar
273		#define SIGSEGV_FAULT_INSTRUCTION               scp->regs->nip
274	+	#define SIGSEGV_REGISTER_FILE                   (unsigned int *)&scp->regs->nip, (unsigned int *)(scp->regs->gpr)
275	+	#define SIGSEGV_SKIP_INSTRUCTION                powerpc_skip_instruction
276	+	#endif
277	+	#if (defined(alpha) || defined(__alpha__))
278	+	#include <asm/sigcontext.h>
279	+	#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
280	+	#define SIGSEGV_FAULT_ADDRESS                   get_fault_address(scp)
281	+	#define SIGSEGV_FAULT_INSTRUCTION               scp->sc_pc
282	+
283	+	// From Boehm's GC 6.0alpha8
284	+	static sigsegv_address_t get_fault_address(struct sigcontext *scp)
285	+	{
286	+	unsigned int instruction = *((unsigned int *)(scp->sc_pc));
287	+	unsigned long fault_address = scp->sc_regs[(instruction >> 16) & 0x1f];
288	+	fault_address += (signed long)(signed short)(instruction & 0xffff);
289	+	return (sigsegv_address_t)fault_address;
290	+	}
291		#endif
292		#endif
293
294		// Irix 5 or 6 on MIPS
295		#if (defined(sgi) || defined(__sgi)) && (defined(SYSTYPE_SVR4) || defined(__SYSTYPE_SVR4))
296	+	#include <ucontext.h>
297		#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
298		#define SIGSEGV_FAULT_ADDRESS                   scp->sc_badvaddr
299		#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGSEGV)
300		#endif
301
302	+	// HP-UX
303	+	#if (defined(hpux) || defined(__hpux__))
304	+	#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
305	+	#define SIGSEGV_FAULT_ADDRESS                   scp->sc_sl.sl_ss.ss_narrow.ss_cr21
306	+	#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGSEGV) FAULT_HANDLER(SIGBUS)
307	+	#endif
308	+
309		// OSF/1 on Alpha
310		#if defined(__osf__)
311	+	#include <ucontext.h>
312		#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
313		#define SIGSEGV_FAULT_ADDRESS                   scp->sc_traparg_a0
314		#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGSEGV)
#	Line 107 | Line 326 | static bool sigsegv_do_install_handler(i
326		#if (defined(m68k) || defined(__m68k__))
327		#include <m68k/frame.h>
328		#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
329	<	#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	<	})
329	>	#define SIGSEGV_FAULT_ADDRESS                   get_fault_address(scp)
330		#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGSEGV)
331	+
332	+	// Use decoding scheme from BasiliskII/m68k native
333	+	static sigsegv_address_t get_fault_address(struct sigcontext *scp)
334	+	{
335	+	struct sigstate {
336	+	int ss_flags;
337	+	struct frame ss_frame;
338	+	};
339	+	struct sigstate *state = (struct sigstate *)scp->sc_ap;
340	+	char *fault_addr;
341	+	switch (state->ss_frame.f_format) {
342	+	case 7:         /* 68040 access error */
343	+	/* "code" is sometimes unreliable (i.e. contains NULL or a bogus address), reason unknown */
344	+	fault_addr = state->ss_frame.f_fmt7.f_fa;
345	+	break;
346	+	default:
347	+	fault_addr = (char *)code;
348	+	break;
349	+	}
350	+	return (sigsegv_address_t)fault_addr;
351	+	}
352		#else
353		#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, void *scp, char *addr
354		#define SIGSEGV_FAULT_ADDRESS                   addr
355		#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGBUS)
356		#endif
357		#endif
358	+
359	+	// MacOS X
360	+	#if defined(__APPLE__) && defined(__MACH__)
361	+	#if (defined(ppc) || defined(__ppc__))
362	+	#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
363	+	#define SIGSEGV_FAULT_ADDRESS                   get_fault_address(scp)
364	+	#define SIGSEGV_FAULT_INSTRUCTION               scp->sc_ir
365	+	#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGBUS)
366	+	#define SIGSEGV_REGISTER_FILE                   (unsigned int *)&scp->sc_ir, &((unsigned int *) scp->sc_regs)[2]
367	+	#define SIGSEGV_SKIP_INSTRUCTION                powerpc_skip_instruction
368	+
369	+	// Use decoding scheme from SheepShaver
370	+	static sigsegv_address_t get_fault_address(struct sigcontext *scp)
371	+	{
372	+	unsigned int   nip = (unsigned int) scp->sc_ir;
373	+	unsigned int * gpr = &((unsigned int *) scp->sc_regs)[2];
374	+	instruction_t  instr;
375	+
376	+	powerpc_decode_instruction(&instr, nip, gpr);
377	+	return (sigsegv_address_t)instr.addr;
378	+	}
379	+	#endif
380	+	#endif
381	+	#endif
382	+
383	+
384	+	/*
385	+	*  Instruction skipping
386	+	*/
387	+
388	+	#ifdef HAVE_SIGSEGV_SKIP_INSTRUCTION
389	+	// Decode and skip X86 instruction
390	+	#if (defined(i386) || defined(__i386__))
391	+	#if defined(__linux__)
392	+	enum {
393	+	X86_REG_EIP = 14,
394	+	X86_REG_EAX = 11,
395	+	X86_REG_ECX = 10,
396	+	X86_REG_EDX = 9,
397	+	X86_REG_EBX = 8,
398	+	X86_REG_ESP = 7,
399	+	X86_REG_EBP = 6,
400	+	X86_REG_ESI = 5,
401	+	X86_REG_EDI = 4
402	+	};
403	+	#endif
404	+	#if defined(__NetBSD__) || defined(__FreeBSD__)
405	+	enum {
406	+	X86_REG_EIP = 10,
407	+	X86_REG_EAX = 7,
408	+	X86_REG_ECX = 6,
409	+	X86_REG_EDX = 5,
410	+	X86_REG_EBX = 4,
411	+	X86_REG_ESP = 13,
412	+	X86_REG_EBP = 2,
413	+	X86_REG_ESI = 1,
414	+	X86_REG_EDI = 0
415	+	};
416	+	#endif
417	+	// FIXME: this is partly redundant with the instruction decoding phase
418	+	// to discover transfer type and register number
419	+	static inline int ix86_step_over_modrm(unsigned char * p)
420	+	{
421	+	int mod = (p[0] >> 6) & 3;
422	+	int rm = p[0] & 7;
423	+	int offset = 0;
424	+
425	+	// ModR/M Byte
426	+	switch (mod) {
427	+	case 0: // [reg]
428	+	if (rm == 5) return 4; // disp32
429	+	break;
430	+	case 1: // disp8[reg]
431	+	offset = 1;
432	+	break;
433	+	case 2: // disp32[reg]
434	+	offset = 4;
435	+	break;
436	+	case 3: // register
437	+	return 0;
438	+	}
439	+
440	+	// SIB Byte
441	+	if (rm == 4) {
442	+	if (mod == 0 && (p[1] & 7) == 5)
443	+	offset = 5; // disp32[index]
444	+	else
445	+	offset++;
446	+	}
447	+
448	+	return offset;
449	+	}
450	+
451	+	static bool ix86_skip_instruction(unsigned int * regs)
452	+	{
453	+	unsigned char * eip = (unsigned char *)regs[X86_REG_EIP];
454	+
455	+	if (eip == 0)
456	+	return false;
457	+
458	+	transfer_type_t transfer_type = TYPE_UNKNOWN;
459	+	transfer_size_t transfer_size = SIZE_LONG;
460	+
461	+	int reg = -1;
462	+	int len = 0;
463	+
464	+	// Operand size prefix
465	+	if (*eip == 0x66) {
466	+	eip++;
467	+	len++;
468	+	transfer_size = SIZE_WORD;
469	+	}
470	+
471	+	// Decode instruction
472	+	switch (eip[0]) {
473	+	case 0x0f:
474	+	switch (eip[1]) {
475	+	case 0xb6: // MOVZX r32, r/m8
476	+	case 0xb7: // MOVZX r32, r/m16
477	+	switch (eip[2] & 0xc0) {
478	+	case 0x80:
479	+	reg = (eip[2] >> 3) & 7;
480	+	transfer_type = TYPE_LOAD;
481	+	break;
482	+	case 0x40:
483	+	reg = (eip[2] >> 3) & 7;
484	+	transfer_type = TYPE_LOAD;
485	+	break;
486	+	case 0x00:
487	+	reg = (eip[2] >> 3) & 7;
488	+	transfer_type = TYPE_LOAD;
489	+	break;
490	+	}
491	+	len += 3 + ix86_step_over_modrm(eip + 2);
492	+	break;
493	+	}
494	+	break;
495	+	case 0x8a: // MOV r8, r/m8
496	+	transfer_size = SIZE_BYTE;
497	+	case 0x8b: // MOV r32, r/m32 (or 16-bit operation)
498	+	switch (eip[1] & 0xc0) {
499	+	case 0x80:
500	+	reg = (eip[1] >> 3) & 7;
501	+	transfer_type = TYPE_LOAD;
502	+	break;
503	+	case 0x40:
504	+	reg = (eip[1] >> 3) & 7;
505	+	transfer_type = TYPE_LOAD;
506	+	break;
507	+	case 0x00:
508	+	reg = (eip[1] >> 3) & 7;
509	+	transfer_type = TYPE_LOAD;
510	+	break;
511	+	}
512	+	len += 2 + ix86_step_over_modrm(eip + 1);
513	+	break;
514	+	case 0x88: // MOV r/m8, r8
515	+	transfer_size = SIZE_BYTE;
516	+	case 0x89: // MOV r/m32, r32 (or 16-bit operation)
517	+	switch (eip[1] & 0xc0) {
518	+	case 0x80:
519	+	reg = (eip[1] >> 3) & 7;
520	+	transfer_type = TYPE_STORE;
521	+	break;
522	+	case 0x40:
523	+	reg = (eip[1] >> 3) & 7;
524	+	transfer_type = TYPE_STORE;
525	+	break;
526	+	case 0x00:
527	+	reg = (eip[1] >> 3) & 7;
528	+	transfer_type = TYPE_STORE;
529	+	break;
530	+	}
531	+	len += 2 + ix86_step_over_modrm(eip + 1);
532	+	break;
533	+	}
534	+
535	+	if (transfer_type == TYPE_UNKNOWN) {
536	+	// Unknown machine code, let it crash. Then patch the decoder
537	+	return false;
538	+	}
539	+
540	+	if (transfer_type == TYPE_LOAD && reg != -1) {
541	+	static const int x86_reg_map[8] = {
542	+	X86_REG_EAX, X86_REG_ECX, X86_REG_EDX, X86_REG_EBX,
543	+	X86_REG_ESP, X86_REG_EBP, X86_REG_ESI, X86_REG_EDI
544	+	};
545	+
546	+	if (reg < 0 || reg >= 8)
547	+	return false;
548	+
549	+	int rloc = x86_reg_map[reg];
550	+	switch (transfer_size) {
551	+	case SIZE_BYTE:
552	+	regs[rloc] = (regs[rloc] & ~0xff);
553	+	break;
554	+	case SIZE_WORD:
555	+	regs[rloc] = (regs[rloc] & ~0xffff);
556	+	break;
557	+	case SIZE_LONG:
558	+	regs[rloc] = 0;
559	+	break;
560	+	}
561	+	}
562	+
563	+	#if DEBUG
564	+	printf("%08x: %s %s access", regs[X86_REG_EIP],
565	+	transfer_size == SIZE_BYTE ? "byte" : transfer_size == SIZE_WORD ? "word" : "long",
566	+	transfer_type == TYPE_LOAD ? "read" : "write");
567	+
568	+	if (reg != -1) {
569	+	static const char * x86_reg_str_map[8] = {
570	+	"eax", "ecx", "edx", "ebx",
571	+	"esp", "ebp", "esi", "edi"
572	+	};
573	+	printf(" %s register %%%s", transfer_type == TYPE_LOAD ? "to" : "from", x86_reg_str_map[reg]);
574	+	}
575	+	printf(", %d bytes instruction\n", len);
576	+	#endif
577	+
578	+	regs[X86_REG_EIP] += len;
579	+	return true;
580	+	}
581	+	#endif
582	+
583	+	// Decode and skip PPC instruction
584	+	#if (defined(powerpc) || defined(__powerpc__) || defined(__ppc__))
585	+	static bool powerpc_skip_instruction(unsigned int * nip_p, unsigned int * regs)
586	+	{
587	+	instruction_t instr;
588	+	powerpc_decode_instruction(&instr, *nip_p, regs);
589	+
590	+	if (instr.transfer_type == TYPE_UNKNOWN) {
591	+	// Unknown machine code, let it crash. Then patch the decoder
592	+	return false;
593	+	}
594	+
595	+	#if DEBUG
596	+	printf("%08x: %s %s access", *nip_p,
597	+	instr.transfer_size == SIZE_BYTE ? "byte" : instr.transfer_size == SIZE_WORD ? "word" : "long",
598	+	instr.transfer_type == TYPE_LOAD ? "read" : "write");
599	+
600	+	if (instr.addr_mode == MODE_U || instr.addr_mode == MODE_UX)
601	+	printf(" r%d (ra = %08x)\n", instr.ra, instr.addr);
602	+	if (instr.transfer_type == TYPE_LOAD)
603	+	printf(" r%d (rd = 0)\n", instr.rd);
604	+	#endif
605	+
606	+	if (instr.addr_mode == MODE_U || instr.addr_mode == MODE_UX)
607	+	regs[instr.ra] = instr.addr;
608	+	if (instr.transfer_type == TYPE_LOAD)
609	+	regs[instr.rd] = 0;
610	+
611	+	*nip_p += 4;
612	+	return true;
613	+	}
614	+	#endif
615		#endif
616
617		// Fallbacks
#	Line 152 | Line 632 | static bool sigsegv_do_install_handler(i
632		#ifdef HAVE_SIGSEGV_RECOVERY
633		static void sigsegv_handler(SIGSEGV_FAULT_HANDLER_ARGLIST)
634		{
635	+	sigsegv_address_t fault_address = (sigsegv_address_t)SIGSEGV_FAULT_ADDRESS;
636	+	sigsegv_address_t fault_instruction = (sigsegv_address_t)SIGSEGV_FAULT_INSTRUCTION;
637	+	bool fault_recovered = false;
638	+
639		// Call user's handler and reinstall the global handler, if required
640	<	if (sigsegv_user_handler((sigsegv_address_t)SIGSEGV_FAULT_ADDRESS, (sigsegv_address_t)SIGSEGV_FAULT_INSTRUCTION)) {
640	>	if (sigsegv_fault_handler(fault_address, fault_instruction)) {
641		#if (defined(HAVE_SIGACTION) ? defined(SIGACTION_NEED_REINSTALL) : defined(SIGNAL_NEED_REINSTALL))
642		sigsegv_do_install_handler(sig);
643		#endif
644	+	fault_recovered = true;
645		}
646	<	else {
646	>	#if HAVE_SIGSEGV_SKIP_INSTRUCTION
647	>	else if (sigsegv_ignore_fault) {
648	>	// Call the instruction skipper with the register file available
649	>	if (SIGSEGV_SKIP_INSTRUCTION(SIGSEGV_REGISTER_FILE))
650	>	fault_recovered = true;
651	>	}
652	>	#endif
653	>
654	>	if (!fault_recovered) {
655		// FAIL: reinstall default handler for "safe" crash
656		#define FAULT_HANDLER(sig) signal(sig, SIG_DFL);
657		SIGSEGV_ALL_SIGNALS
658		#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		}
664		}
665		#endif
#	Line 209 | Line 706 | static bool sigsegv_do_install_handler(i
706		}
707		#endif
708
709	<	bool sigsegv_install_handler(sigsegv_handler_t handler)
709	>	bool sigsegv_install_handler(sigsegv_fault_handler_t handler)
710		{
711		#ifdef HAVE_SIGSEGV_RECOVERY
712	<	sigsegv_user_handler = handler;
712	>	sigsegv_fault_handler = handler;
713		bool success = true;
714		#define FAULT_HANDLER(sig) success = success && sigsegv_do_install_handler(sig);
715		SIGSEGV_ALL_SIGNALS
#	Line 232 | Line 729 | bool sigsegv_install_handler(sigsegv_han
729		void sigsegv_deinstall_handler(void)
730		{
731		#ifdef HAVE_SIGSEGV_RECOVERY
732	<	sigsegv_user_handler = 0;
732	>	sigsegv_fault_handler = 0;
733		#define FAULT_HANDLER(sig) signal(sig, SIG_DFL);
734		SIGSEGV_ALL_SIGNALS
735		#undef FAULT_HANDLER
736		#endif
737		}
738
739	+
740	+	/*
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	+	/*
751	+	*  Set callback function when we cannot handle the fault
752	+	*/
753	+
754	+	void sigsegv_set_dump_state(sigsegv_state_dumper_t handler)
755	+	{
756	+	sigsegv_state_dumper = handler;
757	+	}
758	+
759	+
760		/*
761		*  Test program used for configure/test
762		*/
763
764	<	#ifdef CONFIGURE_TEST
764	>	#ifdef CONFIGURE_TEST_SIGSEGV_RECOVERY
765		#include <stdio.h>
766		#include <stdlib.h>
249	–	#include <unistd.h>
767		#include <fcntl.h>
768		#include <sys/mman.h>
769	+	#include "vm_alloc.h"
770
253	–	static caddr_t page = 0;
771		static int page_size;
772	<	static int handler_called = 0;
772	>	static volatile char * page = 0;
773	>	static volatile int handler_called = 0;
774
775		static bool sigsegv_test_handler(sigsegv_address_t fault_address, sigsegv_address_t instruction_address)
776		{
777		handler_called++;
778		if ((fault_address - 123) != page)
779		exit(1);
780	<	if (mprotect((caddr_t)((unsigned long)fault_address & -page_size), page_size, PROT_READ | PROT_WRITE) != 0)
780	>	if (vm_protect((char *)((unsigned long)fault_address & -page_size), page_size, VM_PAGE_READ | VM_PAGE_WRITE) != 0)
781		exit(1);
782		return true;
783		}
784
785	+	#ifdef HAVE_SIGSEGV_SKIP_INSTRUCTION
786	+	static bool sigsegv_insn_handler(sigsegv_address_t fault_address, sigsegv_address_t instruction_address)
787	+	{
788	+	return false;
789	+	}
790	+	#endif
791	+
792		int main(void)
793		{
794	<	int zero_fd = open("/dev/zero", O_RDWR);
270	<	if (zero_fd < 0)
794	>	if (vm_init() < 0)
795		return 1;
796
797		page_size = getpagesize();
798	<	page = (caddr_t)mmap(0, page_size, PROT_READ, MAP_PRIVATE, zero_fd, 0);
799	<	if (page == MAP_FAILED)
798	>	if ((page = (char *)vm_acquire(page_size)) == VM_MAP_FAILED)
799	>	return 1;
800	>
801	>	if (vm_protect((char *)page, page_size, VM_PAGE_READ) < 0)
802		return 1;
803
804		if (!sigsegv_install_handler(sigsegv_test_handler))
#	Line 284 | Line 810 | int main(void)
810		if (handler_called != 1)
811		return 1;
812
813	+	#ifdef HAVE_SIGSEGV_SKIP_INSTRUCTION
814	+	if (!sigsegv_install_handler(sigsegv_insn_handler))
815	+	return 1;
816	+
817	+	if (vm_protect((char *)page, page_size, VM_PAGE_READ | VM_PAGE_WRITE) < 0)
818	+	return 1;
819	+
820	+	for (int i = 0; i < page_size; i++)
821	+	page[i] = (i + 1) % page_size;
822	+
823	+	if (vm_protect((char *)page, page_size, VM_PAGE_NOACCESS) < 0)
824	+	return 1;
825	+
826	+	sigsegv_set_ignore_state(true);
827	+
828	+	#define TEST_SKIP_INSTRUCTION(TYPE) do {                                \
829	+	const unsigned int TAG = 0x12345678;                    \
830	+	TYPE data = *((TYPE *)(page + sizeof(TYPE)));   \
831	+	volatile unsigned int effect = data + TAG;              \
832	+	if (effect != TAG)                                                              \
833	+	return 1;                                                                       \
834	+	} while (0)
835	+
836	+	TEST_SKIP_INSTRUCTION(unsigned char);
837	+	TEST_SKIP_INSTRUCTION(unsigned short);
838	+	TEST_SKIP_INSTRUCTION(unsigned int);
839	+	#endif
840	+
841	+	vm_exit();
842		return 0;
843		}
844		#endif

Diff Legend

–	Removed lines
+	Added lines
<	Changed lines
>	Changed lines