[ViewVC] Diff of: 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 1.42 by gbeauche, 2004-01-19T16:59:13Z

+ *  Derived from Bruno Haible's work on his SIGSEGV library for clisp
+ *  <http://clisp.sourceforge.net/>
-<
+ *  Basilisk II (C) 1997-2001 Christian Bauer
->
+ *  MacOS X support derived from the post by Timothy J. Wood to the
->
+ *  omnigroup macosx-dev list:
->
+ *    Mach Exception Handlers 101 (Was Re: ptrace, gdb)
->
+ *    tjw@omnigroup.com Sun, 4 Jun 2000
->
+ *    www.omnigroup.com/mailman/archive/macosx-dev/2000-June/002030.html
->
+ *
->
+ *  Basilisk II (C) 1997-2004 Christian Bauer
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+#include "config.h"
+#endif
-+
+#include <list>
-+
+#include <stdio.h>
+#include <signal.h>
+#include "sigsegv.h"
-+
+#ifndef NO_STD_NAMESPACE
-+
+using std::list;
-+
+#endif
-+
+// Return value type of a signal handler (standard type if not defined)
+#ifndef RETSIGTYPE
+#define RETSIGTYPE void
+typedef RETSIGTYPE (*signal_handler)(int);
+// User's SIGSEGV handler
-<
+static sigsegv_handler_t sigsegv_user_handler = 0;
->
+static sigsegv_fault_handler_t sigsegv_fault_handler = 0;
->
->
+// Function called to dump state if we can't handle the fault
->
+static sigsegv_state_dumper_t sigsegv_state_dumper = 0;
+// Actual SIGSEGV handler installer
+static bool sigsegv_do_install_handler(int sig);
+/*
-+
+ *  Instruction decoding aids
-+
+ */
-+
-+
+// Transfer size
-+
+enum transfer_size_t {
-+
+        SIZE_UNKNOWN,
-+
+        SIZE_BYTE,
-+
+        SIZE_WORD, // 2 bytes
-+
+        SIZE_LONG, // 4 bytes
-+
+        SIZE_QUAD, // 8 bytes
-+
+};
-+
-+
+// Transfer type
-+
+typedef sigsegv_transfer_type_t transfer_type_t;
-+
-+
+#if (defined(powerpc) || defined(__powerpc__) || defined(__ppc__))
-+
+// Addressing mode
-+
+enum addressing_mode_t {
-+
+        MODE_UNKNOWN,
-+
+        MODE_NORM,
-+
+        MODE_U,
-+
+        MODE_X,
-+
+        MODE_UX
-+
+};
-+
-+
+// Decoded instruction
-+
+struct instruction_t {
-+
+        transfer_type_t         transfer_type;
-+
+        transfer_size_t         transfer_size;
-+
+        addressing_mode_t       addr_mode;
-+
+        unsigned int            addr;
-+
+        char                            ra, rd;
-+
+};
-+
-+
+static void powerpc_decode_instruction(instruction_t *instruction, unsigned int nip, unsigned int * gpr)
-+
+{
-+
+        // Get opcode and divide into fields
-+
+        unsigned int opcode = *((unsigned int *)nip);
-+
+        unsigned int primop = opcode >> 26;
-+
+        unsigned int exop = (opcode >> 1) & 0x3ff;
-+
+        unsigned int ra = (opcode >> 16) & 0x1f;
-+
+        unsigned int rb = (opcode >> 11) & 0x1f;
-+
+        unsigned int rd = (opcode >> 21) & 0x1f;
-+
+        signed int imm = (signed short)(opcode & 0xffff);
-+
-+
+        // Analyze opcode
-+
+        transfer_type_t transfer_type = SIGSEGV_TRANSFER_UNKNOWN;
-+
+        transfer_size_t transfer_size = SIZE_UNKNOWN;
-+
+        addressing_mode_t addr_mode = MODE_UNKNOWN;
-+
+        switch (primop) {
-+
+        case 31:
-+
+                switch (exop) {
-+
+                case 23:        // lwzx
-+
+                        transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_X; break;
-+
+                case 55:        // lwzux
-+
+                        transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_UX; break;
-+
+                case 87:        // lbzx
-+
+                        transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_X; break;
-+
+                case 119:       // lbzux
-+
+                        transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_UX; break;
-+
+                case 151:       // stwx
-+
+                        transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_X; break;
-+
+                case 183:       // stwux
-+
+                        transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_UX; break;
-+
+                case 215:       // stbx
-+
+                        transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_X; break;
-+
+                case 247:       // stbux
-+
+                        transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_UX; break;
-+
+                case 279:       // lhzx
-+
+                        transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_X; break;
-+
+                case 311:       // lhzux
-+
+                        transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_UX; break;
-+
+                case 343:       // lhax
-+
+                        transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_X; break;
-+
+                case 375:       // lhaux
-+
+                        transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_UX; break;
-+
+                case 407:       // sthx
-+
+                        transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_X; break;
-+
+                case 439:       // sthux
-+
+                        transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_UX; break;
-+
+                }
-+
+                break;
-+
-+
+        case 32:        // lwz
-+
+                transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_NORM; break;
-+
+        case 33:        // lwzu
-+
+                transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_U; break;
-+
+        case 34:        // lbz
-+
+                transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_NORM; break;
-+
+        case 35:        // lbzu
-+
+                transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_U; break;
-+
+        case 36:        // stw
-+
+                transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_NORM; break;
-+
+        case 37:        // stwu
-+
+                transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_U; break;
-+
+        case 38:        // stb
-+
+                transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_NORM; break;
-+
+        case 39:        // stbu
-+
+                transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_U; break;
-+
+        case 40:        // lhz
-+
+                transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_NORM; break;
-+
+        case 41:        // lhzu
-+
+                transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_U; break;
-+
+        case 42:        // lha
-+
+                transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_NORM; break;
-+
+        case 43:        // lhau
-+
+                transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_U; break;
-+
+        case 44:        // sth
-+
+                transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_NORM; break;
-+
+        case 45:        // sthu
-+
+                transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_U; break;
-+
+        }
-+
-+
+        // Calculate effective address
-+
+        unsigned int addr = 0;
-+
+        switch (addr_mode) {
-+
+        case MODE_X:
-+
+        case MODE_UX:
-+
+                if (ra == 0)
-+
+                        addr = gpr[rb];
-+
+                else
-+
+                        addr = gpr[ra] + gpr[rb];
-+
+                break;
-+
+        case MODE_NORM:
-+
+        case MODE_U:
-+
+                if (ra == 0)
-+
+                        addr = (signed int)(signed short)imm;
-+
+                else
-+
+                        addr = gpr[ra] + (signed int)(signed short)imm;
-+
+                break;
-+
+        default:
-+
+                break;
-+
+        }
-+
-+
+        // Commit decoded instruction
-+
+        instruction->addr = addr;
-+
+        instruction->addr_mode = addr_mode;
-+
+        instruction->transfer_type = transfer_type;
-+
+        instruction->transfer_size = transfer_size;
-+
+        instruction->ra = ra;
-+
+        instruction->rd = rd;
-+
+}
-+
+#endif
-+
-+
-+
+/*
+ *  OS-dependant SIGSEGV signals support section
+ */
+#if HAVE_SIGINFO_T
+// Generic extended signal handler
-+
+#if defined(__NetBSD__) || defined(__FreeBSD__)
-+
+#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGBUS)
-+
+#else
+#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGSEGV)
-<
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, siginfo_t *sip, void *
->
+#endif
->
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, siginfo_t *sip, void *scp
->
+#define SIGSEGV_FAULT_HANDLER_ARGLIST_1 siginfo_t *sip, void *scp
->
+#define SIGSEGV_FAULT_HANDLER_ARGS              sip, scp
+#define SIGSEGV_FAULT_ADDRESS                   sip->si_addr
-+
+#if (defined(sgi) || defined(__sgi))
-+
+#include <ucontext.h>
-+
+#define SIGSEGV_CONTEXT_REGS                    (((ucontext_t *)scp)->uc_mcontext.gregs)
-+
+#define SIGSEGV_FAULT_INSTRUCTION               (unsigned long)SIGSEGV_CONTEXT_REGS[CTX_EPC]
-+
+#if (defined(mips) || defined(__mips))
-+
+#define SIGSEGV_REGISTER_FILE                   SIGSEGV_CONTEXT_REGS
-+
+#define SIGSEGV_SKIP_INSTRUCTION                mips_skip_instruction
-+
+#endif
-+
+#endif
-+
+#if defined(__sun__)
-+
+#if (defined(sparc) || defined(__sparc__))
-+
+#include <sys/stack.h>
-+
+#include <sys/regset.h>
-+
+#include <sys/ucontext.h>
-+
+#define SIGSEGV_CONTEXT_REGS                    (((ucontext_t *)scp)->uc_mcontext.gregs)
-+
+#define SIGSEGV_FAULT_INSTRUCTION               SIGSEGV_CONTEXT_REGS[REG_PC]
-+
+#define SIGSEGV_SPARC_GWINDOWS                  (((ucontext_t *)scp)->uc_mcontext.gwins)
-+
+#define SIGSEGV_SPARC_RWINDOW                   (struct rwindow *)((char *)SIGSEGV_CONTEXT_REGS[REG_SP] + STACK_BIAS)
-+
+#define SIGSEGV_REGISTER_FILE                   ((unsigned long *)SIGSEGV_CONTEXT_REGS), SIGSEGV_SPARC_GWINDOWS, SIGSEGV_SPARC_RWINDOW
-+
+#define SIGSEGV_SKIP_INSTRUCTION                sparc_skip_instruction
-+
+#endif
-+
+#endif
-+
+#if defined(__FreeBSD__)
-+
+#if (defined(i386) || defined(__i386__))
-+
+#define SIGSEGV_FAULT_INSTRUCTION               (((struct sigcontext *)scp)->sc_eip)
-+
+#define SIGSEGV_REGISTER_FILE                   ((unsigned long *)&(((struct sigcontext *)scp)->sc_edi)) /* EDI is the first GPR (even below EIP) in sigcontext */
-+
+#define SIGSEGV_SKIP_INSTRUCTION                ix86_skip_instruction
-+
+#endif
-+
+#endif
-+
+#if defined(__linux__)
-+
+#if (defined(i386) || defined(__i386__))
-+
+#include <sys/ucontext.h>
-+
+#define SIGSEGV_CONTEXT_REGS                    (((ucontext_t *)scp)->uc_mcontext.gregs)
-+
+#define SIGSEGV_FAULT_INSTRUCTION               SIGSEGV_CONTEXT_REGS[14] /* should use REG_EIP instead */
-+
+#define SIGSEGV_REGISTER_FILE                   (unsigned long *)SIGSEGV_CONTEXT_REGS
-+
+#define SIGSEGV_SKIP_INSTRUCTION                ix86_skip_instruction
-+
+#endif
-+
+#if (defined(x86_64) || defined(__x86_64__))
-+
+#include <sys/ucontext.h>
-+
+#define SIGSEGV_CONTEXT_REGS                    (((ucontext_t *)scp)->uc_mcontext.gregs)
-+
+#define SIGSEGV_FAULT_INSTRUCTION               SIGSEGV_CONTEXT_REGS[16] /* should use REG_RIP instead */
-+
+#define SIGSEGV_REGISTER_FILE                   (unsigned long *)SIGSEGV_CONTEXT_REGS
-+
+#define SIGSEGV_SKIP_INSTRUCTION                ix86_skip_instruction
-+
+#endif
-+
+#if (defined(ia64) || defined(__ia64__))
-+
+#define SIGSEGV_FAULT_INSTRUCTION               (((struct sigcontext *)scp)->sc_ip & ~0x3ULL) /* slot number is in bits 0 and 1 */
-+
+#endif
-+
+#if (defined(powerpc) || defined(__powerpc__))
-+
+#include <sys/ucontext.h>
-+
+#define SIGSEGV_CONTEXT_REGS                    (((ucontext_t *)scp)->uc_mcontext.regs)
-+
+#define SIGSEGV_FAULT_INSTRUCTION               (SIGSEGV_CONTEXT_REGS->nip)
-+
+#define SIGSEGV_REGISTER_FILE                   (unsigned int *)&SIGSEGV_CONTEXT_REGS->nip, (unsigned int *)(SIGSEGV_CONTEXT_REGS->gpr)
-+
+#define SIGSEGV_SKIP_INSTRUCTION                powerpc_skip_instruction
-+
+#endif
-+
+#if (defined(hppa) || defined(__hppa__))
-+
+#undef  SIGSEGV_FAULT_ADDRESS
-+
+#define SIGSEGV_FAULT_ADDRESS                   sip->si_ptr
-+
+#endif
-+
+#if (defined(arm) || defined(__arm__))
-+
+#include <asm/ucontext.h> /* use kernel structure, glibc may not be in sync */
-+
+#define SIGSEGV_CONTEXT_REGS                    (((struct ucontext *)scp)->uc_mcontext)
-+
+#define SIGSEGV_FAULT_INSTRUCTION               (SIGSEGV_CONTEXT_REGS.arm_pc)
-+
+#endif
-+
+#endif
+#endif
+#if HAVE_SIGCONTEXT_SUBTERFUGE
+#if (defined(i386) || defined(__i386__))
+#include <asm/sigcontext.h>
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, struct sigcontext scs
-<
+#define SIGSEGV_FAULT_ADDRESS                   scs.cr2
-<
+#define SIGSEGV_FAULT_INSTRUCTION               scs.eip
->
+#define SIGSEGV_FAULT_HANDLER_ARGLIST_1 struct sigcontext *scp
->
+#define SIGSEGV_FAULT_HANDLER_ARGS              &scs
->
+#define SIGSEGV_FAULT_ADDRESS                   scp->cr2
->
+#define SIGSEGV_FAULT_INSTRUCTION               scp->eip
->
+#define SIGSEGV_REGISTER_FILE                   (unsigned long *)scp
->
+#define SIGSEGV_SKIP_INSTRUCTION                ix86_skip_instruction
+#endif
+#if (defined(sparc) || defined(__sparc__))
+#include <asm/sigcontext.h>
-<
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext* scp, char* addr
->
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp, char *addr
->
+#define SIGSEGV_FAULT_HANDLER_ARGS              sig, code, scp, addr
+#define SIGSEGV_FAULT_ADDRESS                   addr
+#endif
+#if (defined(powerpc) || defined(__powerpc__))
+#include <asm/sigcontext.h>
-<
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, struct sigcontext* scp
->
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, struct sigcontext *scp
->
+#define SIGSEGV_FAULT_HANDLER_ARGS              sig, scp
+#define SIGSEGV_FAULT_ADDRESS                   scp->regs->dar
+#define SIGSEGV_FAULT_INSTRUCTION               scp->regs->nip
-+
+#define SIGSEGV_REGISTER_FILE                   (unsigned int *)&scp->regs->nip, (unsigned int *)(scp->regs->gpr)
-+
+#define SIGSEGV_SKIP_INSTRUCTION                powerpc_skip_instruction
-+
+#endif
-+
+#if (defined(alpha) || defined(__alpha__))
-+
+#include <asm/sigcontext.h>
-+
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
-+
+#define SIGSEGV_FAULT_HANDLER_ARGS              sig, code, scp
-+
+#define SIGSEGV_FAULT_ADDRESS                   get_fault_address(scp)
-+
+#define SIGSEGV_FAULT_INSTRUCTION               scp->sc_pc
-+
+#endif
-+
+#if (defined(arm) || defined(__arm__))
-+
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int r1, int r2, int r3, struct sigcontext sc
-+
+#define SIGSEGV_FAULT_HANDLER_ARGLIST_1 struct sigcontext *scp
-+
+#define SIGSEGV_FAULT_HANDLER_ARGS              &sc
-+
+#define SIGSEGV_FAULT_ADDRESS                   scp->fault_address
-+
+#define SIGSEGV_FAULT_INSTRUCTION               scp->arm_pc
+#endif
+#endif
+// Irix 5 or 6 on MIPS
-<
+#if (defined(sgi) || defined(__sgi)) && (defined(SYSTYPE_SVR4) || defined(__SYSTYPE_SVR4))
->
+#if (defined(sgi) || defined(__sgi)) && (defined(SYSTYPE_SVR4) || defined(_SYSTYPE_SVR4))
->
+#include <ucontext.h>
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
-<
+#define SIGSEGV_FAULT_ADDRESS                   scp->sc_badvaddr
->
+#define SIGSEGV_FAULT_HANDLER_ARGS              sig, code, scp
->
+#define SIGSEGV_FAULT_ADDRESS                   (unsigned long)scp->sc_badvaddr
->
+#define SIGSEGV_FAULT_INSTRUCTION               (unsigned long)scp->sc_pc
+#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGSEGV)
+#endif
-+
+// HP-UX
-+
+#if (defined(hpux) || defined(__hpux__))
-+
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
-+
+#define SIGSEGV_FAULT_HANDLER_ARGS              sig, code, scp
-+
+#define SIGSEGV_FAULT_ADDRESS                   scp->sc_sl.sl_ss.ss_narrow.ss_cr21
-+
+#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGSEGV) FAULT_HANDLER(SIGBUS)
-+
+#endif
-+
+// OSF/1 on Alpha
+#if defined(__osf__)
-+
+#include <ucontext.h>
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
-+
+#define SIGSEGV_FAULT_HANDLER_ARGS              sig, code, scp
+#define SIGSEGV_FAULT_ADDRESS                   scp->sc_traparg_a0
+#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGSEGV)
+#endif
+// AIX
+#if defined(_AIX)
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
-+
+#define SIGSEGV_FAULT_HANDLER_ARGS              sig, code, scp
+#define SIGSEGV_FAULT_ADDRESS                   scp->sc_jmpbuf.jmp_context.o_vaddr
+#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGSEGV)
+#endif
-<
+// NetBSD or FreeBSD
-<
+#if defined(__NetBSD__) || defined(__FreeBSD__)
->
+// NetBSD
->
+#if defined(__NetBSD__)
+#if (defined(m68k) || defined(__m68k__))
+#include <m68k/frame.h>
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
-<
+#define SIGSEGV_FAULT_ADDRESS                   ({                                                                                                                              \
-<
+        struct sigstate {                                                                                                                                                                       \
-<
+                int ss_flags;                                                                                                                                                                   \
-<
+                struct frame ss_frame;                                                                                                                                                  \
-<
+        };                                                                                                                                                                                                      \
-<
+        struct sigstate *state = (struct sigstate *)scp->sc_ap;                                                                                         \
-<
+        char *fault_addr;                                                                                                                                                                       \
-<
+        switch (state->ss_frame.f_format) {                                                                                                                                     \
-<
+        case 7:         /* 68040 access error */                                                                                                                                \
-<
+                /* "code" is sometimes unreliable (i.e. contains NULL or a bogus address), reason unknown */    \
-<
+                fault_addr = state->ss_frame.f_fmt7.f_fa;                                                                                                               \
-<
+                break;                                                                                                                                                                                  \
-<
+        default:                                                                                                                                                                                        \
-<
+                fault_addr = (char *)code;                                                                                                                                              \
-<
+                break;                                                                                                                                                                                  \
-<
+        }                                                                                                                                                                                                       \
-<
+        fault_addr;                                                                                                                                                                                     \
-<
+})
->
+#define SIGSEGV_FAULT_HANDLER_ARGS              sig, code, scp
->
+#define SIGSEGV_FAULT_ADDRESS                   get_fault_address(scp)
+#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGSEGV)
-<
+#else
-<
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, void *scp, char *addr
->
->
+// Use decoding scheme from BasiliskII/m68k native
->
+static sigsegv_address_t get_fault_address(struct sigcontext *scp)
->
+{
->
+        struct sigstate {
->
+                int ss_flags;
->
+                struct frame ss_frame;
->
+        };
->
+        struct sigstate *state = (struct sigstate *)scp->sc_ap;
->
+        char *fault_addr;
->
+        switch (state->ss_frame.f_format) {
->
+        case 7:         /* 68040 access error */
->
+                /* "code" is sometimes unreliable (i.e. contains NULL or a bogus address), reason unknown */
->
+                fault_addr = state->ss_frame.f_fmt7.f_fa;
->
+                break;
->
+        default:
->
+                fault_addr = (char *)code;
->
+                break;
->
+        }
->
+        return (sigsegv_address_t)fault_addr;
->
+}
->
+#endif
->
+#if (defined(alpha) || defined(__alpha__))
->
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
->
+#define SIGSEGV_FAULT_HANDLER_ARGS              sig, code, scp
->
+#define SIGSEGV_FAULT_ADDRESS                   get_fault_address(scp)
->
+#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGBUS)
->
+#endif
->
+#if (defined(i386) || defined(__i386__))
->
+#error "FIXME: need to decode instruction and compute EA"
->
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
->
+#define SIGSEGV_FAULT_HANDLER_ARGS              sig, code, scp
->
+#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGSEGV)
->
+#endif
->
+#endif
->
+#if defined(__FreeBSD__)
->
+#if (defined(i386) || defined(__i386__))
->
+#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGBUS)
->
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp, char *addr
->
+#define SIGSEGV_FAULT_HANDLER_ARGS              sig, code, scp, addr
+#define SIGSEGV_FAULT_ADDRESS                   addr
-+
+#define SIGSEGV_FAULT_INSTRUCTION               scp->sc_eip
-+
+#define SIGSEGV_REGISTER_FILE                   ((unsigned long *)&scp->sc_edi)
-+
+#define SIGSEGV_SKIP_INSTRUCTION                ix86_skip_instruction
-+
+#endif
-+
+#if (defined(alpha) || defined(__alpha__))
-+
+#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGSEGV)
-+
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, char *addr, struct sigcontext *scp
-+
+#define SIGSEGV_FAULT_HANDLER_ARGS              sig, addr, scp
-+
+#define SIGSEGV_FAULT_ADDRESS                   addr
-+
+#define SIGSEGV_FAULT_INSTRUCTION               scp->sc_pc
-+
+#endif
-+
+#endif
-+
-+
+// Extract fault address out of a sigcontext
-+
+#if (defined(alpha) || defined(__alpha__))
-+
+// From Boehm's GC 6.0alpha8
-+
+static sigsegv_address_t get_fault_address(struct sigcontext *scp)
-+
+{
-+
+        unsigned int instruction = *((unsigned int *)(scp->sc_pc));
-+
+        unsigned long fault_address = scp->sc_regs[(instruction >> 16) & 0x1f];
-+
+        fault_address += (signed long)(signed short)(instruction & 0xffff);
-+
+        return (sigsegv_address_t)fault_address;
-+
+}
-+
+#endif
-+
-+
-+
+// MacOS X, not sure which version this works in. Under 10.1
-+
+// vm_protect does not appear to work from a signal handler. Under
-+
+// 10.2 signal handlers get siginfo type arguments but the si_addr
-+
+// field is the address of the faulting instruction and not the
-+
+// address that caused the SIGBUS. Maybe this works in 10.0? In any
-+
+// case with Mach exception handlers there is a way to do what this
-+
+// was meant to do.
-+
+#ifndef HAVE_MACH_EXCEPTIONS
-+
+#if defined(__APPLE__) && defined(__MACH__)
-+
+#if (defined(ppc) || defined(__ppc__))
-+
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   int sig, int code, struct sigcontext *scp
-+
+#define SIGSEGV_FAULT_HANDLER_ARGS              sig, code, scp
-+
+#define SIGSEGV_FAULT_ADDRESS                   get_fault_address(scp)
-+
+#define SIGSEGV_FAULT_INSTRUCTION               scp->sc_ir
+#define SIGSEGV_ALL_SIGNALS                             FAULT_HANDLER(SIGBUS)
-+
+#define SIGSEGV_REGISTER_FILE                   (unsigned int *)&scp->sc_ir, &((unsigned int *) scp->sc_regs)[2]
-+
+#define SIGSEGV_SKIP_INSTRUCTION                powerpc_skip_instruction
-+
-+
+// Use decoding scheme from SheepShaver
-+
+static sigsegv_address_t get_fault_address(struct sigcontext *scp)
-+
+{
-+
+        unsigned int   nip = (unsigned int) scp->sc_ir;
-+
+        unsigned int * gpr = &((unsigned int *) scp->sc_regs)[2];
-+
+        instruction_t  instr;
-+
-+
+        powerpc_decode_instruction(&instr, nip, gpr);
-+
+        return (sigsegv_address_t)instr.addr;
-+
+}
-+
+#endif
-+
+#endif
+#endif
+#endif
-+
-+
+#if HAVE_MACH_EXCEPTIONS
-+
-+
+// This can easily be extended to other Mach systems, but really who
-+
+// uses HURD (oops GNU/HURD), Darwin/x86, NextStep, Rhapsody, or CMU
-+
+// Mach 2.5/3.0?
-+
+#if defined(__APPLE__) && defined(__MACH__)
-+
-+
+#include <sys/types.h>
-+
+#include <stdlib.h>
-+
+#include <stdio.h>
-+
+#include <pthread.h>
-+
-+
+/*
-+
+ * If you are familiar with MIG then you will understand the frustration
-+
+ * that was necessary to get these embedded into C++ code by hand.
-+
+ */
-+
+extern "C" {
-+
+#include <mach/mach.h>
-+
+#include <mach/mach_error.h>
-+
-+
+extern boolean_t exc_server(mach_msg_header_t *, mach_msg_header_t *);
-+
+extern kern_return_t catch_exception_raise(mach_port_t, mach_port_t,
-+
+        mach_port_t, exception_type_t, exception_data_t, mach_msg_type_number_t);
-+
+extern kern_return_t exception_raise(mach_port_t, mach_port_t, mach_port_t,
-+
+        exception_type_t, exception_data_t, mach_msg_type_number_t);
-+
+extern kern_return_t exception_raise_state(mach_port_t, exception_type_t,
-+
+        exception_data_t, mach_msg_type_number_t, thread_state_flavor_t *,
-+
+        thread_state_t, mach_msg_type_number_t, thread_state_t, mach_msg_type_number_t *);
-+
+extern kern_return_t exception_raise_state_identity(mach_port_t, mach_port_t, mach_port_t,
-+
+        exception_type_t, exception_data_t, mach_msg_type_number_t, thread_state_flavor_t *,
-+
+        thread_state_t, mach_msg_type_number_t, thread_state_t, mach_msg_type_number_t *);
-+
+}
-+
-+
+// Could make this dynamic by looking for a result of MIG_ARRAY_TOO_LARGE
-+
+#define HANDLER_COUNT 64
-+
-+
+// structure to tuck away existing exception handlers
-+
+typedef struct _ExceptionPorts {
-+
+        mach_msg_type_number_t maskCount;
-+
+        exception_mask_t masks[HANDLER_COUNT];
-+
+        exception_handler_t handlers[HANDLER_COUNT];
-+
+        exception_behavior_t behaviors[HANDLER_COUNT];
-+
+        thread_state_flavor_t flavors[HANDLER_COUNT];
-+
+} ExceptionPorts;
-+
-+
+// exception handler thread
-+
+static pthread_t exc_thread;
-+
-+
+// place where old exception handler info is stored
-+
+static ExceptionPorts ports;
-+
-+
+// our exception port
-+
+static mach_port_t _exceptionPort = MACH_PORT_NULL;
-+
-+
+#define MACH_CHECK_ERROR(name,ret) \
-+
+if (ret != KERN_SUCCESS) { \
-+
+        mach_error(#name, ret); \
-+
+        exit (1); \
-+
+}
-+
-+
+#define SIGSEGV_FAULT_ADDRESS                   code[1]
-+
+#define SIGSEGV_FAULT_INSTRUCTION               get_fault_instruction(thread, state)
-+
+#define SIGSEGV_FAULT_HANDLER_INVOKE(ADDR, IP)  ((code[0] == KERN_PROTECTION_FAILURE) ? sigsegv_fault_handler(ADDR, IP) : SIGSEGV_RETURN_FAILURE)
-+
+#define SIGSEGV_FAULT_HANDLER_ARGLIST   mach_port_t thread, exception_data_t code, ppc_thread_state_t *state
-+
+#define SIGSEGV_FAULT_HANDLER_ARGS              thread, code, &state
-+
+#define SIGSEGV_SKIP_INSTRUCTION                powerpc_skip_instruction
-+
+#define SIGSEGV_REGISTER_FILE                   &state->srr0, &state->r0
-+
-+
+// Given a suspended thread, stuff the current instruction and
-+
+// registers into state.
-+
+//
-+
+// It would have been nice to have this be ppc/x86 independant which
-+
+// could have been done easily with a thread_state_t instead of
-+
+// ppc_thread_state_t, but because of the way this is called it is
-+
+// easier to do it this way.
-+
+#if (defined(ppc) || defined(__ppc__))
-+
+static inline sigsegv_address_t get_fault_instruction(mach_port_t thread, ppc_thread_state_t *state)
-+
+{
-+
+        kern_return_t krc;
-+
+        mach_msg_type_number_t count;
-+
-+
+        count = MACHINE_THREAD_STATE_COUNT;
-+
+        krc = thread_get_state(thread, MACHINE_THREAD_STATE, (thread_state_t)state, &count);
-+
+        MACH_CHECK_ERROR (thread_get_state, krc);
-+
-+
+        return (sigsegv_address_t)state->srr0;
-+
+}
-+
+#endif
-+
-+
+// Since there can only be one exception thread running at any time
-+
+// this is not a problem.
-+
+#define MSG_SIZE 512
-+
+static char msgbuf[MSG_SIZE];
-+
+static char replybuf[MSG_SIZE];
-+
-+
+/*
-+
+ * This is the entry point for the exception handler thread. The job
-+
+ * of this thread is to wait for exception messages on the exception
-+
+ * port that was setup beforehand and to pass them on to exc_server.
-+
+ * exc_server is a MIG generated function that is a part of Mach.
-+
+ * Its job is to decide what to do with the exception message. In our
-+
+ * case exc_server calls catch_exception_raise on our behalf. After
-+
+ * exc_server returns, it is our responsibility to send the reply.
-+
+ */
-+
+static void *
-+
+handleExceptions(void *priv)
-+
+{
-+
+        mach_msg_header_t *msg, *reply;
-+
+        kern_return_t krc;
-+
-+
+        msg = (mach_msg_header_t *)msgbuf;
-+
+        reply = (mach_msg_header_t *)replybuf;
-+
-+
+        for (;;) {
-+
+                krc = mach_msg(msg, MACH_RCV_MSG, MSG_SIZE, MSG_SIZE,
-+
+                                _exceptionPort, 0, MACH_PORT_NULL);
-+
+                MACH_CHECK_ERROR(mach_msg, krc);
-+
-+
+                if (!exc_server(msg, reply)) {
-+
+                        fprintf(stderr, "exc_server hated the message\n");
-+
+                        exit(1);
-+
+                }
-+
-+
+                krc = mach_msg(reply, MACH_SEND_MSG, reply->msgh_size, 0,
-+
+                                 msg->msgh_local_port, 0, MACH_PORT_NULL);
-+
+                if (krc != KERN_SUCCESS) {
-+
+                        fprintf(stderr, "Error sending message to original reply port, krc = %d, %s",
-+
+                                krc, mach_error_string(krc));
-+
+                        exit(1);
-+
+                }
-+
+        }
-+
+}
-+
+#endif
-+
+#endif
-+
-+
-+
+/*
-+
+ *  Instruction skipping
-+
+ */
-+
-+
+#ifdef HAVE_SIGSEGV_SKIP_INSTRUCTION
-+
+// Decode and skip X86 instruction
-+
+#if (defined(i386) || defined(__i386__)) || defined(__x86_64__)
-+
+#if defined(__linux__)
-+
+enum {
-+
+#if (defined(i386) || defined(__i386__))
-+
+        X86_REG_EIP = 14,
-+
+        X86_REG_EAX = 11,
-+
+        X86_REG_ECX = 10,
-+
+        X86_REG_EDX = 9,
-+
+        X86_REG_EBX = 8,
-+
+        X86_REG_ESP = 7,
-+
+        X86_REG_EBP = 6,
-+
+        X86_REG_ESI = 5,
-+
+        X86_REG_EDI = 4
-+
+#endif
-+
+#if defined(__x86_64__)
-+
+        X86_REG_R8  = 0,
-+
+        X86_REG_R9  = 1,
-+
+        X86_REG_R10 = 2,
-+
+        X86_REG_R11 = 3,
-+
+        X86_REG_R12 = 4,
-+
+        X86_REG_R13 = 5,
-+
+        X86_REG_R14 = 6,
-+
+        X86_REG_R15 = 7,
-+
+        X86_REG_EDI = 8,
-+
+        X86_REG_ESI = 9,
-+
+        X86_REG_EBP = 10,
-+
+        X86_REG_EBX = 11,
-+
+        X86_REG_EDX = 12,
-+
+        X86_REG_EAX = 13,
-+
+        X86_REG_ECX = 14,
-+
+        X86_REG_ESP = 15,
-+
+        X86_REG_EIP = 16
-+
+#endif
-+
+};
-+
+#endif
-+
+#if defined(__NetBSD__) || defined(__FreeBSD__)
-+
+enum {
-+
+#if (defined(i386) || defined(__i386__))
-+
+        X86_REG_EIP = 10,
-+
+        X86_REG_EAX = 7,
-+
+        X86_REG_ECX = 6,
-+
+        X86_REG_EDX = 5,
-+
+        X86_REG_EBX = 4,
-+
+        X86_REG_ESP = 13,
-+
+        X86_REG_EBP = 2,
-+
+        X86_REG_ESI = 1,
-+
+        X86_REG_EDI = 0
-+
+#endif
-+
+};
-+
+#endif
-+
+// FIXME: this is partly redundant with the instruction decoding phase
-+
+// to discover transfer type and register number
-+
+static inline int ix86_step_over_modrm(unsigned char * p)
-+
+{
-+
+        int mod = (p[0] >> 6) & 3;
-+
+        int rm = p[0] & 7;
-+
+        int offset = 0;
-+
-+
+        // ModR/M Byte
-+
+        switch (mod) {
-+
+        case 0: // [reg]
-+
+                if (rm == 5) return 4; // disp32
-+
+                break;
-+
+        case 1: // disp8[reg]
-+
+                offset = 1;
-+
+                break;
-+
+        case 2: // disp32[reg]
-+
+                offset = 4;
-+
+                break;
-+
+        case 3: // register
-+
+                return 0;
-+
+        }
-+
-+
+        // SIB Byte
-+
+        if (rm == 4) {
-+
+                if (mod == 0 && (p[1] & 7) == 5)
-+
+                        offset = 5; // disp32[index]
-+
+                else
-+
+                        offset++;
-+
+        }
-+
-+
+        return offset;
-+
+}
-+
-+
+static bool ix86_skip_instruction(unsigned long * regs)
-+
+{
-+
+        unsigned char * eip = (unsigned char *)regs[X86_REG_EIP];
-+
-+
+        if (eip == 0)
-+
+                return false;
-+
-+
+        transfer_type_t transfer_type = SIGSEGV_TRANSFER_UNKNOWN;
-+
+        transfer_size_t transfer_size = SIZE_LONG;
-+
-+
+        int reg = -1;
-+
+        int len = 0;
-+
-+
+#if DEBUG
-+
+        printf("IP: %p [%02x %02x %02x %02x...]\n",
-+
+                   eip, eip[0], eip[1], eip[2], eip[3]);
-+
+#endif
-+
-+
+        // Operand size prefix
-+
+        if (*eip == 0x66) {
-+
+                eip++;
-+
+                len++;
-+
+                transfer_size = SIZE_WORD;
-+
+        }
-+
-+
+        // REX prefix
-+
+#if defined(__x86_64__)
-+
+        struct rex_t {
-+
+                unsigned char W;
-+
+                unsigned char R;
-+
+                unsigned char X;
-+
+                unsigned char B;
-+
+        };
-+
+        rex_t rex = { 0, 0, 0, 0 };
-+
+        bool has_rex = false;
-+
+        if ((*eip & 0xf0) == 0x40) {
-+
+                has_rex = true;
-+
+                const unsigned char b = *eip;
-+
+                rex.W = b & (1 << 3);
-+
+                rex.R = b & (1 << 2);
-+
+                rex.X = b & (1 << 1);
-+
+                rex.B = b & (1 << 0);
-+
+#if DEBUG
-+
+                printf("REX: %c,%c,%c,%c\n",
-+
+                           rex.W ? 'W' : '_',
-+
+                           rex.R ? 'R' : '_',
-+
+                           rex.X ? 'X' : '_',
-+
+                           rex.B ? 'B' : '_');
-+
+#endif
-+
+                eip++;
-+
+                len++;
-+
+                if (rex.W)
-+
+                        transfer_size = SIZE_QUAD;
-+
+        }
-+
+#else
-+
+        const bool has_rex = false;
-+
+#endif
-+
-+
+        // Decode instruction
-+
+        switch (eip[0]) {
-+
+        case 0x0f:
-+
+            switch (eip[1]) {
-+
+            case 0xb6: // MOVZX r32, r/m8
-+
+            case 0xb7: // MOVZX r32, r/m16
-+
+                switch (eip[2] & 0xc0) {
-+
+                case 0x80:
-+
+                    reg = (eip[2] >> 3) & 7;
-+
+                    transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+                    break;
-+
+                case 0x40:
-+
+                    reg = (eip[2] >> 3) & 7;
-+
+                    transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+                    break;
-+
+                case 0x00:
-+
+                    reg = (eip[2] >> 3) & 7;
-+
+                    transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+                    break;
-+
+                }
-+
+                len += 3 + ix86_step_over_modrm(eip + 2);
-+
+                break;
-+
+            }
-+
+          break;
-+
+        case 0x8a: // MOV r8, r/m8
-+
+                transfer_size = SIZE_BYTE;
-+
+        case 0x8b: // MOV r32, r/m32 (or 16-bit operation)
-+
+                switch (eip[1] & 0xc0) {
-+
+                case 0x80:
-+
+                        reg = (eip[1] >> 3) & 7;
-+
+                        transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+                        break;
-+
+                case 0x40:
-+
+                        reg = (eip[1] >> 3) & 7;
-+
+                        transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+                        break;
-+
+                case 0x00:
-+
+                        reg = (eip[1] >> 3) & 7;
-+
+                        transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+                        break;
-+
+                }
-+
+                len += 2 + ix86_step_over_modrm(eip + 1);
-+
+                break;
-+
+        case 0x88: // MOV r/m8, r8
-+
+                transfer_size = SIZE_BYTE;
-+
+        case 0x89: // MOV r/m32, r32 (or 16-bit operation)
-+
+                switch (eip[1] & 0xc0) {
-+
+                case 0x80:
-+
+                        reg = (eip[1] >> 3) & 7;
-+
+                        transfer_type = SIGSEGV_TRANSFER_STORE;
-+
+                        break;
-+
+                case 0x40:
-+
+                        reg = (eip[1] >> 3) & 7;
-+
+                        transfer_type = SIGSEGV_TRANSFER_STORE;
-+
+                        break;
-+
+                case 0x00:
-+
+                        reg = (eip[1] >> 3) & 7;
-+
+                        transfer_type = SIGSEGV_TRANSFER_STORE;
-+
+                        break;
-+
+                }
-+
+                len += 2 + ix86_step_over_modrm(eip + 1);
-+
+                break;
-+
+        }
-+
-+
+        if (transfer_type == SIGSEGV_TRANSFER_UNKNOWN) {
-+
+                // Unknown machine code, let it crash. Then patch the decoder
-+
+                return false;
-+
+        }
-+
-+
+#if defined(__x86_64__)
-+
+        if (rex.R)
-+
+                reg += 8;
-+
+#endif
-+
-+
+        if (transfer_type == SIGSEGV_TRANSFER_LOAD && reg != -1) {
-+
+                static const int x86_reg_map[] = {
-+
+                        X86_REG_EAX, X86_REG_ECX, X86_REG_EDX, X86_REG_EBX,
-+
+                        X86_REG_ESP, X86_REG_EBP, X86_REG_ESI, X86_REG_EDI,
-+
+#if defined(__x86_64__)
-+
+                        X86_REG_R8,  X86_REG_R9,  X86_REG_R10, X86_REG_R11,
-+
+                        X86_REG_R12, X86_REG_R13, X86_REG_R14, X86_REG_R15,
-+
+#endif
-+
+                };
-+
-+
+                if (reg < 0 || reg >= (sizeof(x86_reg_map)/sizeof(x86_reg_map[0]) - 1))
-+
+                        return false;
-+
-+
+                // Set 0 to the relevant register part
-+
+                // NOTE: this is only valid for MOV alike instructions
-+
+                int rloc = x86_reg_map[reg];
-+
+                switch (transfer_size) {
-+
+                case SIZE_BYTE:
-+
+                        if (has_rex || reg < 4)
-+
+                                regs[rloc] = (regs[rloc] & ~0x00ffL);
-+
+                        else {
-+
+                                rloc = x86_reg_map[reg - 4];
-+
+                                regs[rloc] = (regs[rloc] & ~0xff00L);
-+
+                        }
-+
+                        break;
-+
+                case SIZE_WORD:
-+
+                        regs[rloc] = (regs[rloc] & ~0xffffL);
-+
+                        break;
-+
+                case SIZE_LONG:
-+
+                case SIZE_QUAD: // zero-extension
-+
+                        regs[rloc] = 0;
-+
+                        break;
-+
+                }
-+
+        }
-+
-+
+#if DEBUG
-+
+        printf("%08x: %s %s access", regs[X86_REG_EIP],
-+
+                   transfer_size == SIZE_BYTE ? "byte" :
-+
+                   transfer_size == SIZE_WORD ? "word" :
-+
+                   transfer_size == SIZE_LONG ? "long" :
-+
+                   transfer_size == SIZE_QUAD ? "quad" : "unknown",
-+
+                   transfer_type == SIGSEGV_TRANSFER_LOAD ? "read" : "write");
-+
-+
+        if (reg != -1) {
-+
+                static const char * x86_byte_reg_str_map[] = {
-+
+                        "al",   "cl",   "dl",   "bl",
-+
+                        "spl",  "bpl",  "sil",  "dil",
-+
+                        "r8b",  "r9b",  "r10b", "r11b",
-+
+                        "r12b", "r13b", "r14b", "r15b",
-+
+                        "ah",   "ch",   "dh",   "bh",
-+
+                };
-+
+                static const char * x86_word_reg_str_map[] = {
-+
+                        "ax",   "cx",   "dx",   "bx",
-+
+                        "sp",   "bp",   "si",   "di",
-+
+                        "r8w",  "r9w",  "r10w", "r11w",
-+
+                        "r12w", "r13w", "r14w", "r15w",
-+
+                };
-+
+                static const char *x86_long_reg_str_map[] = {
-+
+                        "eax",  "ecx",  "edx",  "ebx",
-+
+                        "esp",  "ebp",  "esi",  "edi",
-+
+                        "r8d",  "r9d",  "r10d", "r11d",
-+
+                        "r12d", "r13d", "r14d", "r15d",
-+
+                };
-+
+                static const char *x86_quad_reg_str_map[] = {
-+
+                        "rax", "rcx", "rdx", "rbx",
-+
+                        "rsp", "rbp", "rsi", "rdi",
-+
+                        "r8",  "r9",  "r10", "r11",
-+
+                        "r12", "r13", "r14", "r15",
-+
+                };
-+
+                const char * reg_str = NULL;
-+
+                switch (transfer_size) {
-+
+                case SIZE_BYTE:
-+
+                        reg_str = x86_byte_reg_str_map[(!has_rex && reg >= 4 ? 12 : 0) + reg];
-+
+                        break;
-+
+                case SIZE_WORD: reg_str = x86_word_reg_str_map[reg]; break;
-+
+                case SIZE_LONG: reg_str = x86_long_reg_str_map[reg]; break;
-+
+                case SIZE_QUAD: reg_str = x86_quad_reg_str_map[reg]; break;
-+
+                }
-+
+                if (reg_str)
-+
+                        printf(" %s register %%%s",
-+
+                                   transfer_type == SIGSEGV_TRANSFER_LOAD ? "to" : "from",
-+
+                                   reg_str);
-+
+        }
-+
+        printf(", %d bytes instruction\n", len);
-+
+#endif
-+
-+
+        regs[X86_REG_EIP] += len;
-+
+        return true;
-+
+}
-+
+#endif
-+
-+
+// Decode and skip PPC instruction
-+
+#if (defined(powerpc) || defined(__powerpc__) || defined(__ppc__))
-+
+static bool powerpc_skip_instruction(unsigned int * nip_p, unsigned int * regs)
-+
+{
-+
+        instruction_t instr;
-+
+        powerpc_decode_instruction(&instr, *nip_p, regs);
-+
-+
+        if (instr.transfer_type == SIGSEGV_TRANSFER_UNKNOWN) {
-+
+                // Unknown machine code, let it crash. Then patch the decoder
-+
+                return false;
-+
+        }
-+
-+
+#if DEBUG
-+
+        printf("%08x: %s %s access", *nip_p,
-+
+                   instr.transfer_size == SIZE_BYTE ? "byte" : instr.transfer_size == SIZE_WORD ? "word" : "long",
-+
+                   instr.transfer_type == SIGSEGV_TRANSFER_LOAD ? "read" : "write");
-+
-+
+        if (instr.addr_mode == MODE_U || instr.addr_mode == MODE_UX)
-+
+                printf(" r%d (ra = %08x)\n", instr.ra, instr.addr);
-+
+        if (instr.transfer_type == SIGSEGV_TRANSFER_LOAD)
-+
+                printf(" r%d (rd = 0)\n", instr.rd);
-+
+#endif
-+
-+
+        if (instr.addr_mode == MODE_U || instr.addr_mode == MODE_UX)
-+
+                regs[instr.ra] = instr.addr;
-+
+        if (instr.transfer_type == SIGSEGV_TRANSFER_LOAD)
-+
+                regs[instr.rd] = 0;
-+
-+
+        *nip_p += 4;
-+
+        return true;
-+
+}
-+
+#endif
-+
-+
+// Decode and skip MIPS instruction
-+
+#if (defined(mips) || defined(__mips))
-+
+enum {
-+
+#if (defined(sgi) || defined(__sgi))
-+
+  MIPS_REG_EPC = 35,
-+
+#endif
-+
+};
-+
+static bool mips_skip_instruction(greg_t * regs)
-+
+{
-+
+  unsigned int * epc = (unsigned int *)(unsigned long)regs[MIPS_REG_EPC];
-+
-+
+  if (epc == 0)
-+
+        return false;
-+
-+
+#if DEBUG
-+
+  printf("IP: %p [%08x]\n", epc, epc[0]);
-+
+#endif
-+
-+
+  transfer_type_t transfer_type = SIGSEGV_TRANSFER_UNKNOWN;
-+
+  transfer_size_t transfer_size = SIZE_LONG;
-+
+  int direction = 0;
-+
-+
+  const unsigned int opcode = epc[0];
-+
+  switch (opcode >> 26) {
-+
+  case 32: // Load Byte
-+
+  case 36: // Load Byte Unsigned
-+
+        transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+        transfer_size = SIZE_BYTE;
-+
+        break;
-+
+  case 33: // Load Halfword
-+
+  case 37: // Load Halfword Unsigned
-+
+        transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+        transfer_size = SIZE_WORD;
-+
+        break;
-+
+  case 35: // Load Word
-+
+  case 39: // Load Word Unsigned
-+
+        transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+        transfer_size = SIZE_LONG;
-+
+        break;
-+
+  case 34: // Load Word Left
-+
+        transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+        transfer_size = SIZE_LONG;
-+
+        direction = -1;
-+
+        break;
-+
+  case 38: // Load Word Right
-+
+        transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+        transfer_size = SIZE_LONG;
-+
+        direction = 1;
-+
+        break;
-+
+  case 55: // Load Doubleword
-+
+        transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+        transfer_size = SIZE_QUAD;
-+
+        break;
-+
+  case 26: // Load Doubleword Left
-+
+        transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+        transfer_size = SIZE_QUAD;
-+
+        direction = -1;
-+
+        break;
-+
+  case 27: // Load Doubleword Right
-+
+        transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+        transfer_size = SIZE_QUAD;
-+
+        direction = 1;
-+
+        break;
-+
+  case 40: // Store Byte
-+
+        transfer_type = SIGSEGV_TRANSFER_STORE;
-+
+        transfer_size = SIZE_BYTE;
-+
+        break;
-+
+  case 41: // Store Halfword
-+
+        transfer_type = SIGSEGV_TRANSFER_STORE;
-+
+        transfer_size = SIZE_WORD;
-+
+        break;
-+
+  case 43: // Store Word
-+
+  case 42: // Store Word Left
-+
+  case 46: // Store Word Right
-+
+        transfer_type = SIGSEGV_TRANSFER_STORE;
-+
+        transfer_size = SIZE_LONG;
-+
+        break;
-+
+  case 63: // Store Doubleword
-+
+  case 44: // Store Doubleword Left
-+
+  case 45: // Store Doubleword Right
-+
+        transfer_type = SIGSEGV_TRANSFER_STORE;
-+
+        transfer_size = SIZE_QUAD;
-+
+        break;
-+
+  /* Misc instructions unlikely to be used within CPU emulators */
-+
+  case 48: // Load Linked Word
-+
+        transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+        transfer_size = SIZE_LONG;
-+
+        break;
-+
+  case 52: // Load Linked Doubleword
-+
+        transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+        transfer_size = SIZE_QUAD;
-+
+        break;
-+
+  case 56: // Store Conditional Word
-+
+        transfer_type = SIGSEGV_TRANSFER_STORE;
-+
+        transfer_size = SIZE_LONG;
-+
+        break;
-+
+  case 60: // Store Conditional Doubleword
-+
+        transfer_type = SIGSEGV_TRANSFER_STORE;
-+
+        transfer_size = SIZE_QUAD;
-+
+        break;
-+
+  }
-+
-+
+  if (transfer_type == SIGSEGV_TRANSFER_UNKNOWN) {
-+
+        // Unknown machine code, let it crash. Then patch the decoder
-+
+        return false;
-+
+  }
-+
-+
+  // Zero target register in case of a load operation
-+
+  const int reg = (opcode >> 16) & 0x1f;
-+
+  if (transfer_type == SIGSEGV_TRANSFER_LOAD) {
-+
+        if (direction == 0)
-+
+          regs[reg] = 0;
-+
+        else {
-+
+          // FIXME: untested code
-+
+          unsigned long ea = regs[(opcode >> 21) & 0x1f];
-+
+          ea += (signed long)(signed int)(signed short)(opcode & 0xffff);
-+
+          const int offset = ea & (transfer_size == SIZE_LONG ? 3 : 7);
-+
+          unsigned long value;
-+
+          if (direction > 0) {
-+
+                const unsigned long rmask = ~((1L << ((offset + 1) * 8)) - 1);
-+
+                value = regs[reg] & rmask;
-+
+          }
-+
+          else {
-+
+                const unsigned long lmask = (1L << (offset * 8)) - 1;
-+
+                value = regs[reg] & lmask;
-+
+          }
-+
+          // restore most significant bits
-+
+          if (transfer_size == SIZE_LONG)
-+
+                value = (signed long)(signed int)value;
-+
+          regs[reg] = value;
-+
+        }
-+
+  }
-+
-+
+#if DEBUG
-+
+#if (defined(_ABIN32) || defined(_ABI64))
-+
+  static const char * mips_gpr_names[32] = {
-+
+        "zero", "at",   "v0",   "v1",   "a0",   "a1",   "a2",   "a3",
-+
+        "t0",   "t1",   "t2",   "t3",   "t4",   "t5",   "t6",   "t7",
-+
+        "s0",   "s1",   "s2",   "s3",   "s4",   "s5",   "s6",   "s7",
-+
+        "t8",   "t9",   "k0",   "k1",   "gp",   "sp",   "s8",   "ra"
-+
+  };
-+
+#else
-+
+  static const char * mips_gpr_names[32] = {
-+
+        "zero", "at",   "v0",   "v1",   "a0",   "a1",   "a2",   "a3",
-+
+        "a4",   "a5",   "a6",   "a7",   "t0",   "t1",   "t2",   "t3",
-+
+        "s0",   "s1",   "s2",   "s3",   "s4",   "s5",   "s6",   "s7",
-+
+        "t8",   "t9",   "k0",   "k1",   "gp",   "sp",   "s8",   "ra"
-+
+  };
-+
+#endif
-+
+  printf("%s %s register %s\n",
-+
+                 transfer_size == SIZE_BYTE ? "byte" :
-+
+                 transfer_size == SIZE_WORD ? "word" :
-+
+                 transfer_size == SIZE_LONG ? "long" :
-+
+                 transfer_size == SIZE_QUAD ? "quad" : "unknown",
-+
+                 transfer_type == SIGSEGV_TRANSFER_LOAD ? "load to" : "store from",
-+
+                 mips_gpr_names[reg]);
-+
+#endif
-+
-+
+  regs[MIPS_REG_EPC] += 4;
-+
+  return true;
-+
+}
-+
+#endif
-+
-+
+// Decode and skip SPARC instruction
-+
+#if (defined(sparc) || defined(__sparc__))
-+
+enum {
-+
+#if (defined(__sun__))
-+
+  SPARC_REG_G1 = REG_G1,
-+
+  SPARC_REG_O0 = REG_O0,
-+
+  SPARC_REG_PC = REG_PC,
-+
+#endif
-+
+};
-+
+static bool sparc_skip_instruction(unsigned long * regs, gwindows_t * gwins, struct rwindow * rwin)
-+
+{
-+
+  unsigned int * pc = (unsigned int *)regs[SPARC_REG_PC];
-+
-+
+  if (pc == 0)
-+
+        return false;
-+
-+
+#if DEBUG
-+
+  printf("IP: %p [%08x]\n", pc, pc[0]);
-+
+#endif
-+
-+
+  transfer_type_t transfer_type = SIGSEGV_TRANSFER_UNKNOWN;
-+
+  transfer_size_t transfer_size = SIZE_LONG;
-+
+  bool register_pair = false;
-+
-+
+  const unsigned int opcode = pc[0];
-+
+  if ((opcode >> 30) != 3)
-+
+        return false;
-+
+  switch ((opcode >> 19) & 0x3f) {
-+
+  case 9: // Load Signed Byte
-+
+  case 1: // Load Unsigned Byte
-+
+        transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+        transfer_size = SIZE_BYTE;
-+
+        break;
-+
+  case 10:// Load Signed Halfword
-+
+  case 2: // Load Unsigned Word
-+
+        transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+        transfer_size = SIZE_WORD;
-+
+        break;
-+
+  case 8: // Load Word
-+
+  case 0: // Load Unsigned Word
-+
+        transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+        transfer_size = SIZE_LONG;
-+
+        break;
-+
+  case 11:// Load Extended Word
-+
+        transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+        transfer_size = SIZE_QUAD;
-+
+        break;
-+
+  case 3: // Load Doubleword
-+
+        transfer_type = SIGSEGV_TRANSFER_LOAD;
-+
+        transfer_size = SIZE_LONG;
-+
+        register_pair = true;
-+
+        break;
-+
+  case 5: // Store Byte
-+
+        transfer_type = SIGSEGV_TRANSFER_STORE;
-+
+        transfer_size = SIZE_BYTE;
-+
+        break;
-+
+  case 6: // Store Halfword
-+
+        transfer_type = SIGSEGV_TRANSFER_STORE;
-+
+        transfer_size = SIZE_WORD;
-+
+        break;
-+
+  case 4: // Store Word
-+
+        transfer_type = SIGSEGV_TRANSFER_STORE;
-+
+        transfer_size = SIZE_LONG;
-+
+        break;
-+
+  case 14:// Store Extended Word
-+
+        transfer_type = SIGSEGV_TRANSFER_STORE;
-+
+        transfer_size = SIZE_QUAD;
-+
+        break;
-+
+  case 7: // Store Doubleword
-+
+        transfer_type = SIGSEGV_TRANSFER_STORE;
-+
+        transfer_size = SIZE_WORD;
-+
+        register_pair = true;
-+
+        break;
-+
+  }
-+
-+
+  if (transfer_type == SIGSEGV_TRANSFER_UNKNOWN) {
-+
+        // Unknown machine code, let it crash. Then patch the decoder
-+
+        return false;
-+
+  }
-+
-+
+  // Zero target register in case of a load operation
-+
+  const int reg = (opcode >> 25) & 0x1f;
-+
+  if (transfer_type == SIGSEGV_TRANSFER_LOAD && reg != 0) {
-+
+        // FIXME: code to handle local & input registers is not tested
-+
+        if (reg >= 1 && reg <= 7) {
-+
+          // global registers
-+
+          regs[reg - 1 + SPARC_REG_G1] = 0;
-+
+        }
-+
+        else if (reg >= 8 && reg <= 15) {
-+
+          // output registers
-+
+          regs[reg - 8 + SPARC_REG_O0] = 0;
-+
+        }
-+
+        else if (reg >= 16 && reg <= 23) {
-+
+          // local registers (in register windows)
-+
+          if (gwins)
-+
+                gwins->wbuf->rw_local[reg - 16] = 0;
-+
+          else
-+
+                rwin->rw_local[reg - 16] = 0;
-+
+        }
-+
+        else {
-+
+          // input registers (in register windows)
-+
+          if (gwins)
-+
+                gwins->wbuf->rw_in[reg - 24] = 0;
-+
+          else
-+
+                rwin->rw_in[reg - 24] = 0;
-+
+        }
-+
+  }
-+
-+
+#if DEBUG
-+
+  static const char * reg_names[] = {
-+
+        "g0", "g1", "g2", "g3", "g4", "g5", "g6", "g7",
-+
+        "o0", "o1", "o2", "o3", "o4", "o5", "sp", "o7",
-+
+        "l0", "l1", "l2", "l3", "l4", "l5", "l6", "l7",
-+
+        "i0", "i1", "i2", "i3", "i4", "i5", "fp", "i7"
-+
+  };
-+
+  printf("%s %s register %s\n",
-+
+                 transfer_size == SIZE_BYTE ? "byte" :
-+
+                 transfer_size == SIZE_WORD ? "word" :
-+
+                 transfer_size == SIZE_LONG ? "long" :
-+
+                 transfer_size == SIZE_QUAD ? "quad" : "unknown",
-+
+                 transfer_type == SIGSEGV_TRANSFER_LOAD ? "load to" : "store from",
-+
+                 reg_names[reg]);
-+
+#endif
-+
-+
+  regs[SPARC_REG_PC] += 4;
-+
+  return true;
-+
+}
-+
+#endif
+#endif
+// Fallbacks
+#ifndef SIGSEGV_FAULT_INSTRUCTION
+#define SIGSEGV_FAULT_INSTRUCTION               SIGSEGV_INVALID_PC
+#endif
-+
+#ifndef SIGSEGV_FAULT_HANDLER_ARGLIST_1
-+
+#define SIGSEGV_FAULT_HANDLER_ARGLIST_1 SIGSEGV_FAULT_HANDLER_ARGLIST
-+
+#endif
-+
+#ifndef SIGSEGV_FAULT_HANDLER_INVOKE
-+
+#define SIGSEGV_FAULT_HANDLER_INVOKE(ADDR, IP)  sigsegv_fault_handler(ADDR, IP)
-+
+#endif
+// SIGSEGV recovery supported ?
+#if defined(SIGSEGV_ALL_SIGNALS) && defined(SIGSEGV_FAULT_HANDLER_ARGLIST) && defined(SIGSEGV_FAULT_ADDRESS)
+ *  SIGSEGV global handler
+ */
-+
+#if defined(HAVE_SIGSEGV_RECOVERY) || defined(HAVE_MACH_EXCEPTIONS)
-+
+// This function handles the badaccess to memory.
-+
+// It is called from the signal handler or the exception handler.
-+
+static bool handle_badaccess(SIGSEGV_FAULT_HANDLER_ARGLIST_1)
-+
+{
-+
+        sigsegv_address_t fault_address = (sigsegv_address_t)SIGSEGV_FAULT_ADDRESS;
-+
+        sigsegv_address_t fault_instruction = (sigsegv_address_t)SIGSEGV_FAULT_INSTRUCTION;
-+
-+
+        // Call user's handler and reinstall the global handler, if required
-+
+        switch (SIGSEGV_FAULT_HANDLER_INVOKE(fault_address, fault_instruction)) {
-+
+        case SIGSEGV_RETURN_SUCCESS:
-+
+                return true;
-+
-+
+#if HAVE_SIGSEGV_SKIP_INSTRUCTION
-+
+        case SIGSEGV_RETURN_SKIP_INSTRUCTION:
-+
+                // Call the instruction skipper with the register file
-+
+                // available
-+
+                if (SIGSEGV_SKIP_INSTRUCTION(SIGSEGV_REGISTER_FILE)) {
-+
+#ifdef HAVE_MACH_EXCEPTIONS
-+
+                        // Unlike UNIX signals where the thread state
-+
+                        // is modified off of the stack, in Mach we
-+
+                        // need to actually call thread_set_state to
-+
+                        // have the register values updated.
-+
+                        kern_return_t krc;
-+
-+
+                        krc = thread_set_state(thread,
-+
+                                                                   MACHINE_THREAD_STATE, (thread_state_t)state,
-+
+                                                                   MACHINE_THREAD_STATE_COUNT);
-+
+                        MACH_CHECK_ERROR (thread_get_state, krc);
-+
+#endif
-+
+                        return true;
-+
+                }
-+
+                break;
-+
+#endif
-+
+        }
-+
-+
+        // We can't do anything with the fault_address, dump state?
-+
+        if (sigsegv_state_dumper != 0)
-+
+                sigsegv_state_dumper(fault_address, fault_instruction);
-+
-+
+        return false;
-+
+}
-+
+#endif
-+
-+
-+
+/*
-+
+ * There are two mechanisms for handling a bad memory access,
-+
+ * Mach exceptions and UNIX signals. The implementation specific
-+
+ * code appears below. Its reponsibility is to call handle_badaccess
-+
+ * which is the routine that handles the fault in an implementation
-+
+ * agnostic manner. The implementation specific code below is then
-+
+ * reponsible for checking whether handle_badaccess was able
-+
+ * to handle the memory access error and perform any implementation
-+
+ * specific tasks necessary afterwards.
-+
+ */
-+
-+
+#ifdef HAVE_MACH_EXCEPTIONS
-+
+/*
-+
+ * We need to forward all exceptions that we do not handle.
-+
+ * This is important, there are many exceptions that may be
-+
+ * handled by other exception handlers. For example debuggers
-+
+ * use exceptions and the exception hander is in another
-+
+ * process in such a case. (Timothy J. Wood states in his
-+
+ * message to the list that he based this code on that from
-+
+ * gdb for Darwin.)
-+
+ */
-+
+static inline kern_return_t
-+
+forward_exception(mach_port_t thread_port,
-+
+                                  mach_port_t task_port,
-+
+                                  exception_type_t exception_type,
-+
+                                  exception_data_t exception_data,
-+
+                                  mach_msg_type_number_t data_count,
-+
+                                  ExceptionPorts *oldExceptionPorts)
-+
+{
-+
+        kern_return_t kret;
-+
+        unsigned int portIndex;
-+
+        mach_port_t port;
-+
+        exception_behavior_t behavior;
-+
+        thread_state_flavor_t flavor;
-+
+        thread_state_t thread_state;
-+
+        mach_msg_type_number_t thread_state_count;
-+
-+
+        for (portIndex = 0; portIndex < oldExceptionPorts->maskCount; portIndex++) {
-+
+                if (oldExceptionPorts->masks[portIndex] & (1 << exception_type)) {
-+
+                        // This handler wants the exception
-+
+                        break;
-+
+                }
-+
+        }
-+
-+
+        if (portIndex >= oldExceptionPorts->maskCount) {
-+
+                fprintf(stderr, "No handler for exception_type = %d. Not fowarding\n", exception_type);
-+
+                return KERN_FAILURE;
-+
+        }
-+
-+
+        port = oldExceptionPorts->handlers[portIndex];
-+
+        behavior = oldExceptionPorts->behaviors[portIndex];
-+
+        flavor = oldExceptionPorts->flavors[portIndex];
-+
-+
+        /*
-+
+         fprintf(stderr, "forwarding exception, port = 0x%x, behaviour = %d, flavor = %d\n", port, behavior, flavor);
-+
+         */
-+
-+
+        if (behavior != EXCEPTION_DEFAULT) {
-+
+                thread_state_count = THREAD_STATE_MAX;
-+
+                kret = thread_get_state (thread_port, flavor, thread_state,
-+
+                                                                 &thread_state_count);
-+
+                MACH_CHECK_ERROR (thread_get_state, kret);
-+
+        }
-+
-+
+        switch (behavior) {
-+
+        case EXCEPTION_DEFAULT:
-+
+          // fprintf(stderr, "forwarding to exception_raise\n");
-+
+          kret = exception_raise(port, thread_port, task_port, exception_type,
-+
+                                                         exception_data, data_count);
-+
+          MACH_CHECK_ERROR (exception_raise, kret);
-+
+          break;
-+
+        case EXCEPTION_STATE:
-+
+          // fprintf(stderr, "forwarding to exception_raise_state\n");
-+
+          kret = exception_raise_state(port, exception_type, exception_data,
-+
+                                                                   data_count, &flavor,
-+
+                                                                   thread_state, thread_state_count,
-+
+                                                                   thread_state, &thread_state_count);
-+
+          MACH_CHECK_ERROR (exception_raise_state, kret);
-+
+          break;
-+
+        case EXCEPTION_STATE_IDENTITY:
-+
+          // fprintf(stderr, "forwarding to exception_raise_state_identity\n");
-+
+          kret = exception_raise_state_identity(port, thread_port, task_port,
-+
+                                                                                        exception_type, exception_data,
-+
+                                                                                        data_count, &flavor,
-+
+                                                                                        thread_state, thread_state_count,
-+
+                                                                                        thread_state, &thread_state_count);
-+
+          MACH_CHECK_ERROR (exception_raise_state_identity, kret);
-+
+          break;
-+
+        default:
-+
+          fprintf(stderr, "forward_exception got unknown behavior\n");
-+
+          break;
-+
+        }
-+
-+
+        if (behavior != EXCEPTION_DEFAULT) {
-+
+                kret = thread_set_state (thread_port, flavor, thread_state,
-+
+                                                                 thread_state_count);
-+
+                MACH_CHECK_ERROR (thread_set_state, kret);
-+
+        }
-+
-+
+        return KERN_SUCCESS;
-+
+}
-+
-+
+/*
-+
+ * This is the code that actually handles the exception.
-+
+ * It is called by exc_server. For Darwin 5 Apple changed
-+
+ * this a bit from how this family of functions worked in
-+
+ * Mach. If you are familiar with that it is a little
-+
+ * different. The main variation that concerns us here is
-+
+ * that code is an array of exception specific codes and
-+
+ * codeCount is a count of the number of codes in the code
-+
+ * array. In typical Mach all exceptions have a code
-+
+ * and sub-code. It happens to be the case that for a
-+
+ * EXC_BAD_ACCESS exception the first entry is the type of
-+
+ * bad access that occurred and the second entry is the
-+
+ * faulting address so these entries correspond exactly to
-+
+ * how the code and sub-code are used on Mach.
-+
+ *
-+
+ * This is a MIG interface. No code in Basilisk II should
-+
+ * call this directley. This has to have external C
-+
+ * linkage because that is what exc_server expects.
-+
+ */
-+
+kern_return_t
-+
+catch_exception_raise(mach_port_t exception_port,
-+
+                                          mach_port_t thread,
-+
+                                          mach_port_t task,
-+
+                                          exception_type_t exception,
-+
+                                          exception_data_t code,
-+
+                                          mach_msg_type_number_t codeCount)
-+
+{
-+
+        ppc_thread_state_t state;
-+
+        kern_return_t krc;
-+
-+
+        if ((exception == EXC_BAD_ACCESS)  && (codeCount >= 2)) {
-+
+                if (handle_badaccess(SIGSEGV_FAULT_HANDLER_ARGS))
-+
+                        return KERN_SUCCESS;
-+
+        }
-+
-+
+        // In Mach we do not need to remove the exception handler.
-+
+        // If we forward the exception, eventually some exception handler
-+
+        // will take care of this exception.
-+
+        krc = forward_exception(thread, task, exception, code, codeCount, &ports);
-+
-+
+        return krc;
-+
+}
-+
+#endif
-+
+#ifdef HAVE_SIGSEGV_RECOVERY
-+
+// Handle bad memory accesses with signal handler
+static void sigsegv_handler(SIGSEGV_FAULT_HANDLER_ARGLIST)
-<
+        // Call user's handler and reinstall the global handler, if required
-<
+        if (sigsegv_user_handler((sigsegv_address_t)SIGSEGV_FAULT_ADDRESS, (sigsegv_address_t)SIGSEGV_FAULT_INSTRUCTION)) {
->
+        // Call handler and reinstall the global handler, if required
->
+        if (handle_badaccess(SIGSEGV_FAULT_HANDLER_ARGS)) {
+#if (defined(HAVE_SIGACTION) ? defined(SIGACTION_NEED_REINSTALL) : defined(SIGNAL_NEED_REINSTALL))
+                sigsegv_do_install_handler(sig);
+#endif
-+
+                return;
-<
+        else {
-<
+                // FAIL: reinstall default handler for "safe" crash
->
->
+        // Failure: reinstall default handler for "safe" crash
+#define FAULT_HANDLER(sig) signal(sig, SIG_DFL);
-<
+                SIGSEGV_ALL_SIGNALS
->
+        SIGSEGV_ALL_SIGNALS
+#undef FAULT_HANDLER
-–
+        }
+#endif
+        // Setup SIGSEGV handler to process writes to frame buffer
+#ifdef HAVE_SIGACTION
-<
+        struct sigaction vosf_sa;
-<
+        sigemptyset(&vosf_sa.sa_mask);
-<
+        vosf_sa.sa_sigaction = sigsegv_handler;
-<
+        vosf_sa.sa_flags = SA_SIGINFO;
-<
+        return (sigaction(sig, &vosf_sa, 0) == 0);
->
+        struct sigaction sigsegv_sa;
->
+        sigemptyset(&sigsegv_sa.sa_mask);
->
+        sigsegv_sa.sa_sigaction = sigsegv_handler;
->
+        sigsegv_sa.sa_flags = SA_SIGINFO;
->
+        return (sigaction(sig, &sigsegv_sa, 0) == 0);
+#else
+        return (signal(sig, (signal_handler)sigsegv_handler) != SIG_ERR);
+#endif
+        // Setup SIGSEGV handler to process writes to frame buffer
+#ifdef HAVE_SIGACTION
-<
+        struct sigaction vosf_sa;
-<
+        sigemptyset(&vosf_sa.sa_mask);
-<
+        vosf_sa.sa_handler = (signal_handler)sigsegv_handler;
->
+        struct sigaction sigsegv_sa;
->
+        sigemptyset(&sigsegv_sa.sa_mask);
->
+        sigsegv_sa.sa_handler = (signal_handler)sigsegv_handler;
->
+        sigsegv_sa.sa_flags = 0;
+#if !EMULATED_68K && defined(__NetBSD__)
-<
+        sigaddset(&vosf_sa.sa_mask, SIGALRM);
-<
+        vosf_sa.sa_flags = SA_ONSTACK;
-<
+#else
-<
+        vosf_sa.sa_flags = 0;
->
+        sigaddset(&sigsegv_sa.sa_mask, SIGALRM);
->
+        sigsegv_sa.sa_flags |= SA_ONSTACK;
+#endif
-<
+        return (sigaction(sig, &vosf_sa, 0) == 0);
->
+        return (sigaction(sig, &sigsegv_sa, 0) == 0);
+#else
+        return (signal(sig, (signal_handler)sigsegv_handler) != SIG_ERR);
+#endif
+#endif
-<
+bool sigsegv_install_handler(sigsegv_handler_t handler)
->
+#if defined(HAVE_MACH_EXCEPTIONS)
->
+static bool sigsegv_do_install_handler(sigsegv_fault_handler_t handler)
-<
+#ifdef HAVE_SIGSEGV_RECOVERY
-<
+        sigsegv_user_handler = handler;
->
+        /*
->
+         * Except for the exception port functions, this should be
->
+         * pretty much stock Mach. If later you choose to support
->
+         * other Mach's besides Darwin, just check for __MACH__
->
+         * here and __APPLE__ where the actual differences are.
->
+         */
->
+#if defined(__APPLE__) && defined(__MACH__)
->
+        if (sigsegv_fault_handler != NULL) {
->
+                sigsegv_fault_handler = handler;
->
+                return true;
->
+        }
->
->
+        kern_return_t krc;
->
->
+        // create the the exception port
->
+        krc = mach_port_allocate(mach_task_self(),
->
+                          MACH_PORT_RIGHT_RECEIVE, &_exceptionPort);
->
+        if (krc != KERN_SUCCESS) {
->
+                mach_error("mach_port_allocate", krc);
->
+                return false;
->
+        }
->
->
+        // add a port send right
->
+        krc = mach_port_insert_right(mach_task_self(),
->
+                              _exceptionPort, _exceptionPort,
->
+                              MACH_MSG_TYPE_MAKE_SEND);
->
+        if (krc != KERN_SUCCESS) {
->
+                mach_error("mach_port_insert_right", krc);
->
+                return false;
->
+        }
->
->
+        // get the old exception ports
->
+        ports.maskCount = sizeof (ports.masks) / sizeof (ports.masks[0]);
->
+        krc = thread_get_exception_ports(mach_thread_self(), EXC_MASK_BAD_ACCESS, ports.masks,
->
+                                &ports.maskCount, ports.handlers, ports.behaviors, ports.flavors);
->
+        if (krc != KERN_SUCCESS) {
->
+                mach_error("thread_get_exception_ports", krc);
->
+                return false;
->
+        }
->
->
+        // set the new exception port
->
+        //
->
+        // We could have used EXCEPTION_STATE_IDENTITY instead of
->
+        // EXCEPTION_DEFAULT to get the thread state in the initial
->
+        // message, but it turns out that in the common case this is not
->
+        // neccessary. If we need it we can later ask for it from the
->
+        // suspended thread.
->
+        //
->
+        // Even with THREAD_STATE_NONE, Darwin provides the program
->
+        // counter in the thread state.  The comments in the header file
->
+        // seem to imply that you can count on the GPR's on an exception
->
+        // as well but just to be safe I use MACHINE_THREAD_STATE because
->
+        // you have to ask for all of the GPR's anyway just to get the
->
+        // program counter. In any case because of update effective
->
+        // address from immediate and update address from effective
->
+        // addresses of ra and rb modes (as good an name as any for these
->
+        // addressing modes) used in PPC instructions, you will need the
->
+        // GPR state anyway.
->
+        krc = thread_set_exception_ports(mach_thread_self(), EXC_MASK_BAD_ACCESS, _exceptionPort,
->
+                                EXCEPTION_DEFAULT, MACHINE_THREAD_STATE);
->
+        if (krc != KERN_SUCCESS) {
->
+                mach_error("thread_set_exception_ports", krc);
->
+                return false;
->
+        }
->
->
+        // create the exception handler thread
->
+        if (pthread_create(&exc_thread, NULL, &handleExceptions, NULL) != 0) {
->
+                (void)fprintf(stderr, "creation of exception thread failed\n");
->
+                return false;
->
+        }
->
->
+        // do not care about the exception thread any longer, let is run standalone
->
+        (void)pthread_detach(exc_thread);
->
->
+        sigsegv_fault_handler = handler;
->
+        return true;
->
+#else
->
+        return false;
->
+#endif
->
+}
->
+#endif
->
->
+bool sigsegv_install_handler(sigsegv_fault_handler_t handler)
->
+{
->
+#if defined(HAVE_SIGSEGV_RECOVERY)
+        bool success = true;
+#define FAULT_HANDLER(sig) success = success && sigsegv_do_install_handler(sig);
+        SIGSEGV_ALL_SIGNALS
+#undef FAULT_HANDLER
-+
+        if (success)
-+
+            sigsegv_fault_handler = handler;
+        return success;
-+
+#elif defined(HAVE_MACH_EXCEPTIONS)
-+
+        return sigsegv_do_install_handler(handler);
+#else
+        // FAIL: no siginfo_t nor sigcontext subterfuge is available
+        return false;
+void sigsegv_deinstall_handler(void)
-+
+  // We do nothing for Mach exceptions, the thread would need to be
-+
+  // suspended if not already so, and we might mess with other
-+
+  // exception handlers that came after we registered ours. There is
-+
+  // no need to remove the exception handler, in fact this function is
-+
+  // not called anywhere in Basilisk II.
+#ifdef HAVE_SIGSEGV_RECOVERY
-<
+        sigsegv_user_handler = 0;
->
+        sigsegv_fault_handler = 0;
+#define FAULT_HANDLER(sig) signal(sig, SIG_DFL);
+        SIGSEGV_ALL_SIGNALS
+#undef FAULT_HANDLER
+#endif
-+
-+
+/*
-+
+ *  Set callback function when we cannot handle the fault
-+
+ */
-+
-+
+void sigsegv_set_dump_state(sigsegv_state_dumper_t handler)
-+
+{
-+
+        sigsegv_state_dumper = handler;
-+
+}
-+
-+
+/*
+ *  Test program used for configure/test
+ */
-<
+#ifdef CONFIGURE_TEST
->
+#ifdef CONFIGURE_TEST_SIGSEGV_RECOVERY
+#include <stdio.h>
+#include <stdlib.h>
-–
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/mman.h>
-+
+#include "vm_alloc.h"
-+
-+
+const int REF_INDEX = 123;
-+
+const int REF_VALUE = 45;
-–
+static caddr_t page = 0;
+static int page_size;
-<
+static int handler_called = 0;
->
+static volatile char * page = 0;
->
+static volatile int handler_called = 0;
-<
+static bool sigsegv_test_handler(sigsegv_address_t fault_address, sigsegv_address_t instruction_address)
->
+#ifdef __GNUC__
->
+// Code range where we expect the fault to come from
->
+static void *b_region, *e_region;
->
+#endif
->
->
+static sigsegv_return_t sigsegv_test_handler(sigsegv_address_t fault_address, sigsegv_address_t instruction_address)
-+
+#if DEBUG
-+
+        printf("sigsegv_test_handler(%p, %p)\n", fault_address, instruction_address);
-+
+        printf("expected fault at %p\n", page + REF_INDEX);
-+
+#ifdef __GNUC__
-+
+        printf("expected instruction address range: %p-%p\n", b_region, e_region);
-+
+#endif
-+
+#endif
+        handler_called++;
-<
+        if ((fault_address - 123) != page)
-<
+                exit(1);
-<
+        if (mprotect((caddr_t)((unsigned long)fault_address & -page_size), page_size, PROT_READ | PROT_WRITE) != 0)
-<
+                exit(1);
->
+        if ((fault_address - REF_INDEX) != page)
->
+                exit(10);
->
+#ifdef __GNUC__
->
+        // Make sure reported fault instruction address falls into
->
+        // expected code range
->
+        if (instruction_address != SIGSEGV_INVALID_PC
->
+                && ((instruction_address <  (sigsegv_address_t)b_region) ||
->
+                        (instruction_address >= (sigsegv_address_t)e_region)))
->
+                exit(11);
->
+#endif
->
+        if (vm_protect((char *)((unsigned long)fault_address & -page_size), page_size, VM_PAGE_READ | VM_PAGE_WRITE) != 0)
->
+                exit(12);
->
+        return SIGSEGV_RETURN_SUCCESS;
->
+}
->
->
+#ifdef HAVE_SIGSEGV_SKIP_INSTRUCTION
->
+static sigsegv_return_t sigsegv_insn_handler(sigsegv_address_t fault_address, sigsegv_address_t instruction_address)
->
+{
->
+        if (((unsigned long)fault_address - (unsigned long)page) < page_size) {
->
+#ifdef __GNUC__
->
+                // Make sure reported fault instruction address falls into
->
+                // expected code range
->
+                if (instruction_address != SIGSEGV_INVALID_PC
->
+                        && ((instruction_address <  (sigsegv_address_t)b_region) ||
->
+                                (instruction_address >= (sigsegv_address_t)e_region)))
->
+                        return SIGSEGV_RETURN_FAILURE;
->
+#endif
->
+                return SIGSEGV_RETURN_SKIP_INSTRUCTION;
->
+        }
->
->
+        return SIGSEGV_RETURN_FAILURE;
->
+}
->
->
+// More sophisticated tests for instruction skipper
->
+static bool arch_insn_skipper_tests()
->
+{
->
+#if (defined(i386) || defined(__i386__)) || defined(__x86_64__)
->
+        static const unsigned char code[] = {
->
+x8a, 0x00,                    // mov    (%eax),%al
->
+x8a, 0x2c, 0x18,              // mov    (%eax,%ebx,1),%ch
->
+x88, 0x20,                    // mov    %ah,(%eax)
->
+x88, 0x08,                    // mov    %cl,(%eax)
->
+x66, 0x8b, 0x00,              // mov    (%eax),%ax
->
+x66, 0x8b, 0x0c, 0x18,        // mov    (%eax,%ebx,1),%cx
->
+x66, 0x89, 0x00,              // mov    %ax,(%eax)
->
+x66, 0x89, 0x0c, 0x18,        // mov    %cx,(%eax,%ebx,1)
->
+x8b, 0x00,                    // mov    (%eax),%eax
->
+x8b, 0x0c, 0x18,              // mov    (%eax,%ebx,1),%ecx
->
+x89, 0x00,                    // mov    %eax,(%eax)
->
+x89, 0x0c, 0x18,              // mov    %ecx,(%eax,%ebx,1)
->
+#if defined(__x86_64__)
->
+x44, 0x8a, 0x00,              // mov    (%rax),%r8b
->
+x44, 0x8a, 0x20,              // mov    (%rax),%r12b
->
+x42, 0x8a, 0x3c, 0x10,        // mov    (%rax,%r10,1),%dil
->
+x44, 0x88, 0x00,              // mov    %r8b,(%rax)
->
+x44, 0x88, 0x20,              // mov    %r12b,(%rax)
->
+x42, 0x88, 0x3c, 0x10,        // mov    %dil,(%rax,%r10,1)
->
+x66, 0x44, 0x8b, 0x00,        // mov    (%rax),%r8w
->
+x66, 0x42, 0x8b, 0x0c, 0x10,  // mov    (%rax,%r10,1),%cx
->
+x66, 0x44, 0x89, 0x00,        // mov    %r8w,(%rax)
->
+x66, 0x42, 0x89, 0x0c, 0x10,  // mov    %cx,(%rax,%r10,1)
->
+x44, 0x8b, 0x00,              // mov    (%rax),%r8d
->
+x42, 0x8b, 0x0c, 0x10,        // mov    (%rax,%r10,1),%ecx
->
+x44, 0x89, 0x00,              // mov    %r8d,(%rax)
->
+x42, 0x89, 0x0c, 0x10,        // mov    %ecx,(%rax,%r10,1)
->
+x48, 0x8b, 0x08,              // mov    (%rax),%rcx
->
+x4c, 0x8b, 0x18,              // mov    (%rax),%r11
->
+x4a, 0x8b, 0x0c, 0x10,        // mov    (%rax,%r10,1),%rcx
->
+x4e, 0x8b, 0x1c, 0x10,        // mov    (%rax,%r10,1),%r11
->
+x48, 0x89, 0x08,              // mov    %rcx,(%rax)
->
+x4c, 0x89, 0x18,              // mov    %r11,(%rax)
->
+x4a, 0x89, 0x0c, 0x10,        // mov    %rcx,(%rax,%r10,1)
->
+x4e, 0x89, 0x1c, 0x10,        // mov    %r11,(%rax,%r10,1)
->
+#endif
->
+                             // end
->
+        };
->
+        const int N_REGS = 20;
->
+        unsigned long regs[N_REGS];
->
+        for (int i = 0; i < N_REGS; i++)
->
+                regs[i] = i;
->
+        const unsigned long start_code = (unsigned long)&code;
->
+        regs[X86_REG_EIP] = start_code;
->
+        while ((regs[X86_REG_EIP] - start_code) < (sizeof(code) - 1)
->
+                   && ix86_skip_instruction(regs))
->
+                ; /* simply iterate */
->
+        return (regs[X86_REG_EIP] - start_code) == (sizeof(code) - 1);
->
+#endif
+        return true;
-+
+#endif
+int main(void)
-<
+        int zero_fd = open("/dev/zero", O_RDWR);
-<
+        if (zero_fd < 0)
->
+        if (vm_init() < 0)
+                return 1;
+        page_size = getpagesize();
-<
+        page = (caddr_t)mmap(0, page_size, PROT_READ, MAP_PRIVATE, zero_fd, 0);
-<
+        if (page == MAP_FAILED)
-<
+                return 1;
->
+        if ((page = (char *)vm_acquire(page_size)) == VM_MAP_FAILED)
->
+                return 2;
-<
+        if (!sigsegv_install_handler(sigsegv_test_handler))
-<
+                return 1;
->
+        memset((void *)page, 0, page_size);
->
+        if (vm_protect((char *)page, page_size, VM_PAGE_READ) < 0)
->
+                return 3;
-<
+        page[123] = 45;
-<
+        page[123] = 45;
->
+        if (!sigsegv_install_handler(sigsegv_test_handler))
->
+                return 4;
-+
+#ifdef __GNUC__
-+
+        b_region = &&L_b_region1;
-+
+        e_region = &&L_e_region1;
-+
+#endif
-+
+ L_b_region1:
-+
+        page[REF_INDEX] = REF_VALUE;
-+
+        if (page[REF_INDEX] != REF_VALUE)
-+
+          exit(20);
-+
+        page[REF_INDEX] = REF_VALUE;
-+
+ L_e_region1:
-+
+        if (handler_called != 1)
-<
+                return 1;
->
+                return 5;
->
->
+#ifdef HAVE_SIGSEGV_SKIP_INSTRUCTION
->
+        if (!sigsegv_install_handler(sigsegv_insn_handler))
->
+                return 6;
->
->
+        if (vm_protect((char *)page, page_size, VM_PAGE_READ | VM_PAGE_WRITE) < 0)
->
+                return 7;
->
->
+        for (int i = 0; i < page_size; i++)
->
+                page[i] = (i + 1) % page_size;
->
->
+        if (vm_protect((char *)page, page_size, VM_PAGE_NOACCESS) < 0)
->
+                return 8;
->
->
+#define TEST_SKIP_INSTRUCTION(TYPE) do {                                \
->
+                const unsigned long TAG = 0x12345678 |                  \
->
+                (sizeof(long) == 8 ? 0x9abcdef0UL << 31 : 0);   \
->
+                TYPE data = *((TYPE *)(page + sizeof(TYPE)));   \
->
+                volatile unsigned long effect = data + TAG;             \
->
+                if (effect != TAG)                                                              \
->
+                        return 9;                                                                       \
->
+        } while (0)
->
->
+#ifdef __GNUC__
->
+        b_region = &&L_b_region2;
->
+        e_region = &&L_e_region2;
->
+#endif
->
+ L_b_region2:
->
+        TEST_SKIP_INSTRUCTION(unsigned char);
->
+        TEST_SKIP_INSTRUCTION(unsigned short);
->
+        TEST_SKIP_INSTRUCTION(unsigned int);
->
+        TEST_SKIP_INSTRUCTION(unsigned long);
->
+ L_e_region2:
->
->
+        if (!arch_insn_skipper_tests())
->
+                return 20;
->
+#endif
-+
+        vm_exit();
+        return 0;
+#endif

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+Removed lines
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+Changed lines

Comparing BasiliskII/src/Unix/sigsegv.cpp (file contents): Revision 1.2 by gbeauche, 2001-05-21T03:21:54Z vs. Revision 1.42 by gbeauche, 2004-01-19T16:59:13Z

Diff Legend

Comparing BasiliskII/src/Unix/sigsegv.cpp (file contents):
Revision 1.2 by gbeauche, 2001-05-21T03:21:54Z vs.
Revision 1.42 by gbeauche, 2004-01-19T16:59:13Z