--- BasiliskII/src/Unix/sigsegv.cpp 2002/05/16 15:48:06 1.12 +++ BasiliskII/src/Unix/sigsegv.cpp 2004/12/02 23:29:52 1.49 @@ -4,7 +4,13 @@ * Derived from Bruno Haible's work on his SIGSEGV library for clisp * * - * Basilisk II (C) 1997-2002 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 @@ -29,9 +35,15 @@ #include "config.h" #endif +#include +#include #include #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 @@ -40,9 +52,6 @@ // Type of the system signal handler typedef RETSIGTYPE (*signal_handler)(int); -// Is the fault to be ignored? -static bool sigsegv_ignore_fault = false; - // User's SIGSEGV handler static sigsegv_fault_handler_t sigsegv_fault_handler = 0; @@ -54,6 +63,164 @@ static bool sigsegv_do_install_handler(i /* + * 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 long * gpr) +{ + // Get opcode and divide into fields + unsigned int opcode = *((unsigned int *)(unsigned long)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; + case 58: // ld, ldu, lwa + transfer_type = SIGSEGV_TRANSFER_LOAD; + transfer_size = SIZE_QUAD; + addr_mode = ((opcode & 3) == 1) ? MODE_U : MODE_NORM; + imm &= ~3; + break; + case 62: // std, stdu, stq + transfer_type = SIGSEGV_TRANSFER_STORE; + transfer_size = SIZE_QUAD; + addr_mode = ((opcode & 3) == 1) ? MODE_U : MODE_NORM; + imm &= ~3; + 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 */ @@ -65,12 +232,51 @@ static bool sigsegv_do_install_handler(i #define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV) #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 +#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 +#include +#include +#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 -#define SIGSEGV_FAULT_INSTRUCTION (((ucontext_t *)scp)->uc_mcontext.gregs[14]) /* should use REG_EIP instead */ -#define SIGSEGV_REGISTER_FILE (unsigned long *)(((ucontext_t *)scp)->uc_mcontext.gregs) +#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 +#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__)) @@ -78,7 +284,21 @@ static bool sigsegv_do_install_handler(i #endif #if (defined(powerpc) || defined(__powerpc__)) #include -#define SIGSEGV_FAULT_INSTRUCTION (((ucontext_t *)scp)->uc_mcontext.regs->nip) +#define SIGSEGV_CONTEXT_REGS (((ucontext_t *)scp)->uc_mcontext.regs) +#define SIGSEGV_FAULT_INSTRUCTION (SIGSEGV_CONTEXT_REGS->nip) +#define SIGSEGV_REGISTER_FILE (unsigned long *)&SIGSEGV_CONTEXT_REGS->nip, (unsigned long *)(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 /* 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) +#define SIGSEGV_REGISTER_FILE (&SIGSEGV_CONTEXT_REGS.arm_r0) +#define SIGSEGV_SKIP_INSTRUCTION arm_skip_instruction #endif #endif #endif @@ -90,50 +310,60 @@ static bool sigsegv_do_install_handler(i #if (defined(i386) || defined(__i386__)) #include #define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, struct sigcontext scs -#define SIGSEGV_FAULT_ADDRESS scs.cr2 -#define SIGSEGV_FAULT_INSTRUCTION scs.eip -#define SIGSEGV_REGISTER_FILE (unsigned long *)(&scs) +#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 #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 #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 long *)&scp->regs->nip, (unsigned long *)(scp->regs->gpr) +#define SIGSEGV_SKIP_INSTRUCTION powerpc_skip_instruction #endif #if (defined(alpha) || defined(__alpha__)) #include #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 - -// 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 +#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 +#define SIGSEGV_REGISTER_FILE &scp->arm_r0 +#define SIGSEGV_SKIP_INSTRUCTION arm_skip_instruction #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 #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 @@ -142,6 +372,7 @@ static sigsegv_address_t get_fault_addre #if defined(__osf__) #include #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 @@ -149,155 +380,279 @@ static sigsegv_address_t get_fault_addre // 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 #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 -#define SIGSEGV_FAULT_ADDRESS 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 +// 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 -// From Boehm's GC 6.0alpha8 -#define EXTRACT_OP1(iw) (((iw) & 0xFC000000) >> 26) -#define EXTRACT_OP2(iw) (((iw) & 0x000007FE) >> 1) -#define EXTRACT_REGA(iw) (((iw) & 0x001F0000) >> 16) -#define EXTRACT_REGB(iw) (((iw) & 0x03E00000) >> 21) -#define EXTRACT_REGC(iw) (((iw) & 0x0000F800) >> 11) -#define EXTRACT_DISP(iw) ((short *) &(iw))[1] - +// Use decoding scheme from SheepShaver static sigsegv_address_t get_fault_address(struct sigcontext *scp) { - unsigned int instr = *((unsigned int *) scp->sc_ir); - unsigned int * regs = &((unsigned int *) scp->sc_regs)[2]; - int disp = 0, tmp; - unsigned int baseA = 0, baseB = 0; - unsigned int addr, alignmask = 0xFFFFFFFF; - - switch(EXTRACT_OP1(instr)) { - case 38: /* stb */ - case 39: /* stbu */ - case 54: /* stfd */ - case 55: /* stfdu */ - case 52: /* stfs */ - case 53: /* stfsu */ - case 44: /* sth */ - case 45: /* sthu */ - case 47: /* stmw */ - case 36: /* stw */ - case 37: /* stwu */ - tmp = EXTRACT_REGA(instr); - if(tmp > 0) - baseA = regs[tmp]; - disp = EXTRACT_DISP(instr); - break; - case 31: - switch(EXTRACT_OP2(instr)) { - case 86: /* dcbf */ - case 54: /* dcbst */ - case 1014: /* dcbz */ - case 247: /* stbux */ - case 215: /* stbx */ - case 759: /* stfdux */ - case 727: /* stfdx */ - case 983: /* stfiwx */ - case 695: /* stfsux */ - case 663: /* stfsx */ - case 918: /* sthbrx */ - case 439: /* sthux */ - case 407: /* sthx */ - case 661: /* stswx */ - case 662: /* stwbrx */ - case 150: /* stwcx. */ - case 183: /* stwux */ - case 151: /* stwx */ - case 135: /* stvebx */ - case 167: /* stvehx */ - case 199: /* stvewx */ - case 231: /* stvx */ - case 487: /* stvxl */ - tmp = EXTRACT_REGA(instr); - if(tmp > 0) - baseA = regs[tmp]; - baseB = regs[EXTRACT_REGC(instr)]; - /* determine Altivec alignment mask */ - switch(EXTRACT_OP2(instr)) { - case 167: /* stvehx */ - alignmask = 0xFFFFFFFE; - break; - case 199: /* stvewx */ - alignmask = 0xFFFFFFFC; - break; - case 231: /* stvx */ - alignmask = 0xFFFFFFF0; - break; - case 487: /* stvxl */ - alignmask = 0xFFFFFFF0; - break; - } - break; - case 725: /* stswi */ - tmp = EXTRACT_REGA(instr); - if(tmp > 0) - baseA = regs[tmp]; - break; - default: /* ignore instruction */ - return 0; - break; + 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_WIN32_EXCEPTIONS +#define WIN32_LEAN_AND_MEAN /* avoid including junk */ +#include +#include + +#define SIGSEGV_FAULT_HANDLER_ARGLIST EXCEPTION_POINTERS *ExceptionInfo +#define SIGSEGV_FAULT_HANDLER_ARGS ExceptionInfo +#define SIGSEGV_FAULT_ADDRESS ExceptionInfo->ExceptionRecord->ExceptionInformation[1] +#define SIGSEGV_CONTEXT_REGS ExceptionInfo->ContextRecord +#define SIGSEGV_FAULT_INSTRUCTION SIGSEGV_CONTEXT_REGS->Eip +#define SIGSEGV_REGISTER_FILE ((unsigned long *)&SIGSEGV_CONTEXT_REGS->Edi) +#define SIGSEGV_SKIP_INSTRUCTION ix86_skip_instruction +#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 +#include +#include +#include + +/* + * 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 +#include + +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); } - break; - default: /* ignore instruction */ - return 0; - break; } - - addr = (baseA + baseB) + disp; - addr &= alignmask; - return (sigsegv_address_t)addr; } #endif #endif -#endif + + +/* + * Instruction skipping + */ #ifdef HAVE_SIGSEGV_SKIP_INSTRUCTION // Decode and skip X86 instruction -#if (defined(i386) || defined(__i386__)) +#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, @@ -307,6 +662,56 @@ enum { 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 +#if defined(_WIN32) +enum { +#if (defined(i386) || defined(__i386__)) + X86_REG_EIP = 7, + X86_REG_EAX = 5, + X86_REG_ECX = 4, + X86_REG_EDX = 3, + X86_REG_EBX = 2, + X86_REG_ESP = 10, + X86_REG_EBP = 6, + X86_REG_ESI = 1, + X86_REG_EDI = 0 +#endif }; #endif // FIXME: this is partly redundant with the instruction decoding phase @@ -343,30 +748,24 @@ static inline int ix86_step_over_modrm(u return offset; } -static bool ix86_skip_instruction(sigsegv_address_t fault_instruction, unsigned long * regs) +static bool ix86_skip_instruction(unsigned long * regs) { - unsigned char * eip = (unsigned char *)fault_instruction; + unsigned char * eip = (unsigned char *)regs[X86_REG_EIP]; if (eip == 0) return false; - // Transfer type - enum { - TYPE_UNKNOWN, - TYPE_LOAD, - TYPE_STORE - } transfer_type = TYPE_UNKNOWN; - - // Transfer size - enum { - SIZE_BYTE, - SIZE_WORD, - SIZE_LONG - } transfer_size = SIZE_LONG; + 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++; @@ -374,23 +773,87 @@ static bool ix86_skip_instruction(sigseg 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 + int target_size = SIZE_UNKNOWN; switch (eip[0]) { + case 0x0f: + target_size = transfer_size; + switch (eip[1]) { + case 0xbe: // MOVSX r32, r/m8 + case 0xb6: // MOVZX r32, r/m8 + transfer_size = SIZE_BYTE; + goto do_mov_extend; + case 0xbf: // MOVSX r32, r/m16 + case 0xb7: // MOVZX r32, r/m16 + transfer_size = SIZE_WORD; + goto do_mov_extend; + do_mov_extend: + 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 = TYPE_LOAD; + transfer_type = SIGSEGV_TRANSFER_LOAD; break; case 0x40: reg = (eip[1] >> 3) & 7; - transfer_type = TYPE_LOAD; + transfer_type = SIGSEGV_TRANSFER_LOAD; break; case 0x00: reg = (eip[1] >> 3) & 7; - transfer_type = TYPE_LOAD; + transfer_type = SIGSEGV_TRANSFER_LOAD; break; } len += 2 + ix86_step_over_modrm(eip + 1); @@ -401,44 +864,63 @@ static bool ix86_skip_instruction(sigseg switch (eip[1] & 0xc0) { case 0x80: reg = (eip[1] >> 3) & 7; - transfer_type = TYPE_STORE; + transfer_type = SIGSEGV_TRANSFER_STORE; break; case 0x40: reg = (eip[1] >> 3) & 7; - transfer_type = TYPE_STORE; + transfer_type = SIGSEGV_TRANSFER_STORE; break; case 0x00: reg = (eip[1] >> 3) & 7; - transfer_type = TYPE_STORE; + transfer_type = SIGSEGV_TRANSFER_STORE; break; } len += 2 + ix86_step_over_modrm(eip + 1); break; } + if (target_size == SIZE_UNKNOWN) + target_size = transfer_size; - if (transfer_type == TYPE_UNKNOWN) { + if (transfer_type == SIGSEGV_TRANSFER_UNKNOWN) { // Unknown machine code, let it crash. Then patch the decoder return false; } - if (transfer_type == TYPE_LOAD && reg != -1) { - static const int x86_reg_map[8] = { +#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 + 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 >= 8) + 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) { + switch (target_size) { case SIZE_BYTE: - regs[rloc] = (regs[rloc] & ~0xff); + 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] & ~0xffff); + regs[rloc] = (regs[rloc] & ~0xffffL); break; case SIZE_LONG: + case SIZE_QUAD: // zero-extension regs[rloc] = 0; break; } @@ -446,15 +928,51 @@ static bool ix86_skip_instruction(sigseg #if DEBUG printf("%08x: %s %s access", regs[X86_REG_EIP], - transfer_size == SIZE_BYTE ? "byte" : transfer_size == SIZE_WORD ? "word" : "long", - transfer_type == TYPE_LOAD ? "read" : "write"); + 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_reg_str_map[8] = { - "eax", "ecx", "edx", "ebx", - "esp", "ebp", "esi", "edi" + 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", }; - printf(" %s register %%%s", transfer_type == TYPE_LOAD ? "to" : "from", x86_reg_str_map[reg]); + 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 (target_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 @@ -463,12 +981,494 @@ static bool ix86_skip_instruction(sigseg return true; } #endif + +// Decode and skip PPC instruction +#if (defined(powerpc) || defined(__powerpc__) || defined(__ppc__)) +static bool powerpc_skip_instruction(unsigned long * nip_p, unsigned long * 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" : + instr.transfer_size == SIZE_LONG ? "long" : "quad", + 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 + +// Decode and skip ARM instruction +#if (defined(arm) || defined(__arm__)) +enum { +#if (defined(__linux__)) + ARM_REG_PC = 15, + ARM_REG_CPSR = 16 +#endif +}; +static bool arm_skip_instruction(unsigned long * regs) +{ + unsigned int * pc = (unsigned int *)regs[ARM_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_UNKNOWN; + enum { op_sdt = 1, op_sdth = 2 }; + int op = 0; + + // Handle load/store instructions only + const unsigned int opcode = pc[0]; + switch ((opcode >> 25) & 7) { + case 0: // Halfword and Signed Data Transfer (LDRH, STRH, LDRSB, LDRSH) + op = op_sdth; + // Determine transfer size (S/H bits) + switch ((opcode >> 5) & 3) { + case 0: // SWP instruction + break; + case 1: // Unsigned halfwords + case 3: // Signed halfwords + transfer_size = SIZE_WORD; + break; + case 2: // Signed byte + transfer_size = SIZE_BYTE; + break; + } + break; + case 2: + case 3: // Single Data Transfer (LDR, STR) + op = op_sdt; + // Determine transfer size (B bit) + if (((opcode >> 22) & 1) == 1) + transfer_size = SIZE_BYTE; + else + transfer_size = SIZE_LONG; + break; + default: + // FIXME: support load/store mutliple? + return false; + } + + // Check for invalid transfer size (SWP instruction?) + if (transfer_size == SIZE_UNKNOWN) + return false; + + // Determine transfer type (L bit) + if (((opcode >> 20) & 1) == 1) + transfer_type = SIGSEGV_TRANSFER_LOAD; + else + transfer_type = SIGSEGV_TRANSFER_STORE; + + // Compute offset + int offset; + if (((opcode >> 25) & 1) == 0) { + if (op == op_sdt) + offset = opcode & 0xfff; + else if (op == op_sdth) { + int rm = opcode & 0xf; + if (((opcode >> 22) & 1) == 0) { + // register offset + offset = regs[rm]; + } + else { + // immediate offset + offset = ((opcode >> 4) & 0xf0) | (opcode & 0x0f); + } + } + } + else { + const int rm = opcode & 0xf; + const int sh = (opcode >> 7) & 0x1f; + if (((opcode >> 4) & 1) == 1) { + // we expect only legal load/store instructions + printf("FATAL: invalid shift operand\n"); + return false; + } + const unsigned int v = regs[rm]; + switch ((opcode >> 5) & 3) { + case 0: // logical shift left + offset = sh ? v << sh : v; + break; + case 1: // logical shift right + offset = sh ? v >> sh : 0; + break; + case 2: // arithmetic shift right + if (sh) + offset = ((signed int)v) >> sh; + else + offset = (v & 0x80000000) ? 0xffffffff : 0; + break; + case 3: // rotate right + if (sh) + offset = (v >> sh) | (v << (32 - sh)); + else + offset = (v >> 1) | ((regs[ARM_REG_CPSR] << 2) & 0x80000000); + break; + } + } + if (((opcode >> 23) & 1) == 0) + offset = -offset; + + int rd = (opcode >> 12) & 0xf; + int rn = (opcode >> 16) & 0xf; +#if DEBUG + static const char * reg_names[] = { + "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", + "r9", "r9", "sl", "fp", "ip", "sp", "lr", "pc" + }; + printf("%s %s register %s\n", + transfer_size == SIZE_BYTE ? "byte" : + transfer_size == SIZE_WORD ? "word" : + transfer_size == SIZE_LONG ? "long" : "unknown", + transfer_type == SIGSEGV_TRANSFER_LOAD ? "load to" : "store from", + reg_names[rd]); +#endif + + unsigned int base = regs[rn]; + if (((opcode >> 24) & 1) == 1) + base += offset; + + if (transfer_type == SIGSEGV_TRANSFER_LOAD) + regs[rd] = 0; + + if (((opcode >> 24) & 1) == 0) // post-index addressing + regs[rn] += offset; + else if (((opcode >> 21) & 1) == 1) // write-back address into base + regs[rn] = base; + + regs[ARM_REG_PC] += 4; + return true; +} #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) @@ -480,38 +1480,213 @@ static bool ix86_skip_instruction(sigseg * SIGSEGV global handler */ -#ifdef HAVE_SIGSEGV_RECOVERY -static void sigsegv_handler(SIGSEGV_FAULT_HANDLER_ARGLIST) +// 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; - bool fault_recovered = false; // Call user's handler and reinstall the global handler, if required - if (sigsegv_fault_handler(fault_address, fault_instruction)) { -#if (defined(HAVE_SIGACTION) ? defined(SIGACTION_NEED_REINSTALL) : defined(SIGNAL_NEED_REINSTALL)) - sigsegv_do_install_handler(sig); + 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 - fault_recovered = true; + return true; + } + break; +#endif + case SIGSEGV_RETURN_FAILURE: + return false; } -#if HAVE_SIGSEGV_SKIP_INSTRUCTION - else if (sigsegv_ignore_fault) { - // Call the instruction skipper with the register file available - if (SIGSEGV_SKIP_INSTRUCTION(fault_instruction, SIGSEGV_REGISTER_FILE)) - fault_recovered = true; + + // 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; +} + + +/* + * 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 - if (!fault_recovered) { - // FAIL: reinstall default handler for "safe" crash +#ifdef HAVE_SIGSEGV_RECOVERY +// Handle bad memory accesses with signal handler +static void sigsegv_handler(SIGSEGV_FAULT_HANDLER_ARGLIST) +{ + // 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; + } + + // Failure: reinstall default handler for "safe" crash #define FAULT_HANDLER(sig) signal(sig, SIG_DFL); - SIGSEGV_ALL_SIGNALS + SIGSEGV_ALL_SIGNALS #undef FAULT_HANDLER - - // We can't do anything with the fault_address, dump state? - if (sigsegv_state_dumper != 0) - sigsegv_state_dumper(fault_address, fault_instruction); - } } #endif @@ -525,11 +1700,11 @@ static bool sigsegv_do_install_handler(i { // 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 @@ -541,31 +1716,207 @@ static bool sigsegv_do_install_handler(i { // 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_fault_handler_t handler) +#if defined(HAVE_MACH_EXCEPTIONS) +static bool sigsegv_do_install_handler(sigsegv_fault_handler_t handler) { -#ifdef HAVE_SIGSEGV_RECOVERY + /* + * 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 + +#ifdef HAVE_WIN32_EXCEPTIONS +static LONG WINAPI main_exception_filter(EXCEPTION_POINTERS *ExceptionInfo) +{ + if (sigsegv_fault_handler != NULL + && ExceptionInfo->ExceptionRecord->ExceptionCode == EXCEPTION_ACCESS_VIOLATION + && ExceptionInfo->ExceptionRecord->NumberParameters == 2 + && handle_badaccess(ExceptionInfo)) + return EXCEPTION_CONTINUE_EXECUTION; + + return EXCEPTION_CONTINUE_SEARCH; +} + +#if defined __CYGWIN__ && defined __i386__ +/* In Cygwin programs, SetUnhandledExceptionFilter has no effect because Cygwin + installs a global exception handler. We have to dig deep in order to install + our main_exception_filter. */ + +/* Data structures for the current thread's exception handler chain. + On the x86 Windows uses register fs, offset 0 to point to the current + exception handler; Cygwin mucks with it, so we must do the same... :-/ */ + +/* Magic taken from winsup/cygwin/include/exceptions.h. */ + +struct exception_list { + struct exception_list *prev; + int (*handler) (EXCEPTION_RECORD *, void *, CONTEXT *, void *); +}; +typedef struct exception_list exception_list; + +/* Magic taken from winsup/cygwin/exceptions.cc. */ + +__asm__ (".equ __except_list,0"); + +extern exception_list *_except_list __asm__ ("%fs:__except_list"); + +/* For debugging. _except_list is not otherwise accessible from gdb. */ +static exception_list * +debug_get_except_list () +{ + return _except_list; +} + +/* Cygwin's original exception handler. */ +static int (*cygwin_exception_handler) (EXCEPTION_RECORD *, void *, CONTEXT *, void *); + +/* Our exception handler. */ +static int +libsigsegv_exception_handler (EXCEPTION_RECORD *exception, void *frame, CONTEXT *context, void *dispatch) +{ + EXCEPTION_POINTERS ExceptionInfo; + ExceptionInfo.ExceptionRecord = exception; + ExceptionInfo.ContextRecord = context; + if (main_exception_filter (&ExceptionInfo) == EXCEPTION_CONTINUE_SEARCH) + return cygwin_exception_handler (exception, frame, context, dispatch); + else + return 0; +} + +static void +do_install_main_exception_filter () +{ + /* We cannot insert any handler into the chain, because such handlers + must lie on the stack (?). Instead, we have to replace(!) Cygwin's + global exception handler. */ + cygwin_exception_handler = _except_list->handler; + _except_list->handler = libsigsegv_exception_handler; +} + +#else + +static void +do_install_main_exception_filter () +{ + SetUnhandledExceptionFilter ((LPTOP_LEVEL_EXCEPTION_FILTER) &main_exception_filter); +} +#endif + +static bool sigsegv_do_install_handler(sigsegv_fault_handler_t handler) +{ + static bool main_exception_filter_installed = false; + if (!main_exception_filter_installed) { + do_install_main_exception_filter(); + main_exception_filter_installed = true; + } + sigsegv_fault_handler = handler; + return true; +} +#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) || defined(HAVE_WIN32_EXCEPTIONS) + return sigsegv_do_install_handler(handler); #else // FAIL: no siginfo_t nor sigcontext subterfuge is available return false; @@ -579,22 +1930,20 @@ bool sigsegv_install_handler(sigsegv_fau 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_fault_handler = 0; #define FAULT_HANDLER(sig) signal(sig, SIG_DFL); SIGSEGV_ALL_SIGNALS #undef FAULT_HANDLER #endif -} - - -/* - * SIGSEGV ignore state modifier - */ - -void sigsegv_set_ignore_state(bool ignore_fault) -{ - sigsegv_ignore_fault = ignore_fault; +#ifdef HAVE_WIN32_EXCEPTIONS + sigsegv_fault_handler = NULL; +#endif } @@ -616,27 +1965,124 @@ void sigsegv_set_dump_state(sigsegv_stat #include #include #include +#ifdef HAVE_SYS_MMAN_H #include +#endif #include "vm_alloc.h" +const int REF_INDEX = 123; +const int REF_VALUE = 45; + static int page_size; 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 ((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(1); - return true; + exit(12); + return SIGSEGV_RETURN_SUCCESS; } #ifdef HAVE_SIGSEGV_SKIP_INSTRUCTION -static bool sigsegv_insn_handler(sigsegv_address_t fault_address, sigsegv_address_t instruction_address) +static sigsegv_return_t sigsegv_insn_handler(sigsegv_address_t fault_address, sigsegv_address_t instruction_address) { - return false; +#if DEBUG + printf("sigsegv_insn_handler(%p, %p)\n", fault_address, instruction_address); +#endif + 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[] = { + 0x8a, 0x00, // mov (%eax),%al + 0x8a, 0x2c, 0x18, // mov (%eax,%ebx,1),%ch + 0x88, 0x20, // mov %ah,(%eax) + 0x88, 0x08, // mov %cl,(%eax) + 0x66, 0x8b, 0x00, // mov (%eax),%ax + 0x66, 0x8b, 0x0c, 0x18, // mov (%eax,%ebx,1),%cx + 0x66, 0x89, 0x00, // mov %ax,(%eax) + 0x66, 0x89, 0x0c, 0x18, // mov %cx,(%eax,%ebx,1) + 0x8b, 0x00, // mov (%eax),%eax + 0x8b, 0x0c, 0x18, // mov (%eax,%ebx,1),%ecx + 0x89, 0x00, // mov %eax,(%eax) + 0x89, 0x0c, 0x18, // mov %ecx,(%eax,%ebx,1) +#if defined(__x86_64__) + 0x44, 0x8a, 0x00, // mov (%rax),%r8b + 0x44, 0x8a, 0x20, // mov (%rax),%r12b + 0x42, 0x8a, 0x3c, 0x10, // mov (%rax,%r10,1),%dil + 0x44, 0x88, 0x00, // mov %r8b,(%rax) + 0x44, 0x88, 0x20, // mov %r12b,(%rax) + 0x42, 0x88, 0x3c, 0x10, // mov %dil,(%rax,%r10,1) + 0x66, 0x44, 0x8b, 0x00, // mov (%rax),%r8w + 0x66, 0x42, 0x8b, 0x0c, 0x10, // mov (%rax,%r10,1),%cx + 0x66, 0x44, 0x89, 0x00, // mov %r8w,(%rax) + 0x66, 0x42, 0x89, 0x0c, 0x10, // mov %cx,(%rax,%r10,1) + 0x44, 0x8b, 0x00, // mov (%rax),%r8d + 0x42, 0x8b, 0x0c, 0x10, // mov (%rax,%r10,1),%ecx + 0x44, 0x89, 0x00, // mov %r8d,(%rax) + 0x42, 0x89, 0x0c, 0x10, // mov %ecx,(%rax,%r10,1) + 0x48, 0x8b, 0x08, // mov (%rax),%rcx + 0x4c, 0x8b, 0x18, // mov (%rax),%r11 + 0x4a, 0x8b, 0x0c, 0x10, // mov (%rax,%r10,1),%rcx + 0x4e, 0x8b, 0x1c, 0x10, // mov (%rax,%r10,1),%r11 + 0x48, 0x89, 0x08, // mov %rcx,(%rax) + 0x4c, 0x89, 0x18, // mov %r11,(%rax) + 0x4a, 0x89, 0x0c, 0x10, // mov %rcx,(%rax,%r10,1) + 0x4e, 0x89, 0x1c, 0x10, // mov %r11,(%rax,%r10,1) +#endif + 0 // 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 @@ -645,48 +2091,74 @@ int main(void) if (vm_init() < 0) return 1; +#ifdef _WIN32 + page_size = 4096; +#else page_size = getpagesize(); +#endif if ((page = (char *)vm_acquire(page_size)) == VM_MAP_FAILED) - return 1; + return 2; + memset((void *)page, 0, page_size); if (vm_protect((char *)page, page_size, VM_PAGE_READ) < 0) - return 1; + return 3; if (!sigsegv_install_handler(sigsegv_test_handler)) - return 1; - - page[123] = 45; - page[123] = 45; + 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 1; + return 6; - if (vm_protect((char *)page, page_size, VM_PAGE_WRITE) < 0) - return 1; + 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 1; + return 8; - sigsegv_set_ignore_state(true); - #define TEST_SKIP_INSTRUCTION(TYPE) do { \ - const unsigned int TAG = 0x12345678; \ + const unsigned long TAG = 0x12345678 | \ + (sizeof(long) == 8 ? 0x9abcdef0UL << 31 : 0); \ TYPE data = *((TYPE *)(page + sizeof(TYPE))); \ - volatile unsigned int effect = data + TAG; \ + volatile unsigned long effect = data + TAG; \ if (effect != TAG) \ - return 1; \ + 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); + TEST_SKIP_INSTRUCTION(signed char); + TEST_SKIP_INSTRUCTION(signed short); + TEST_SKIP_INSTRUCTION(signed int); + TEST_SKIP_INSTRUCTION(signed long); + L_e_region2: + + if (!arch_insn_skipper_tests()) + return 20; #endif vm_exit();