src/Unix/main_unix.cpp

/*
 *  main_unix.cpp - Emulation core, Unix implementation
 *
 *  SheepShaver (C) 1997-2005 Christian Bauer and Marc Hellwig
 *
 *  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
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

/*
 *  NOTES:
 *
 *  See main_beos.cpp for a description of the three operating modes.
 *
 *  In addition to that, we have to handle the fact that the MacOS ABI
 *  is slightly different from the SysV ABI used by Linux:
 *    - Stack frames are different (e.g. LR is stored in 8(r1) under
 *      MacOS, but in 4(r1) under Linux)
 *    - There is a pointer to Thread Local Storage (TLS) under Linux with
 *      recent enough glibc. This is r2 in 32-bit mode and r13 in
 *      64-bit mode (PowerOpen/AIX ABI)
 *    - r13 is used as a small data pointer under Linux (but appearently
 *      it is not used this way? To be sure, we specify -msdata=none
 *      in the Makefile)
 *    - There are no TVECTs under Linux; function pointers point
 *      directly to the function code
 *  The Execute*() functions have to account for this. Additionally, we
 *  cannot simply call MacOS functions by getting their TVECT and jumping
 *  to it. Such calls are done via the call_macos*() functions in
 *  asm_linux.S that create a MacOS stack frame, load the TOC pointer
 *  and put the arguments into the right registers.
 *
 *  As on the BeOS, we have to specify an alternate signal stack because
 *  interrupts (and, under Linux, Low Memory accesses) may occur when r1
 *  is pointing to the Kernel Data or to Low Memory. There is one
 *  problem, however, due to the alternate signal stack being global to
 *  all signal handlers. Consider the following scenario:
 *    - The main thread is executing some native PPC MacOS code in
 *      MODE_NATIVE, running on the MacOS stack (somewhere in the Mac RAM).
 *    - A SIGUSR2 interrupt occurs. The kernel switches to the signal
 *      stack and starts executing the SIGUSR2 signal handler.
 *    - The signal handler sees the MODE_NATIVE and calls ppc_interrupt()
 *      to handle a native interrupt.
 *    - ppc_interrupt() sets r1 to point to the Kernel Data and jumps to
 *      the nanokernel.
 *    - The nanokernel accesses a Low Memory global (most likely one of
 *      the XLMs), a SIGSEGV occurs.
 *    - The kernel sees that r1 does not point to the signal stack and
 *      switches to the signal stack again, thus overwriting the data that
 *      the SIGUSR2 handler put there.
 *  The same problem arises when calling ExecutePPC() inside the MODE_EMUL_OP
 *  interrupt handler.
 *
 *  The solution is to set the signal stack to a second, "extra" stack
 *  inside the SIGUSR2 handler before entering the Nanokernel or calling
 *  ExecutePPC (or any function that might cause a mode switch). The signal
 *  stack is restored before exiting the SIGUSR2 handler.
 *
 *  Note that POSIX standard says you can't modify the alternate
 *  signal stack while the process is executing on it. There is a
 *  hackaround though: we install a trampoline SIGUSR2 handler that
 *  sets up an alternate stack itself and calls the real handler.
 *  Then, when we call sigaltstack() there, we no longer get an EPERM,
 *  i.e. it now works.
 *
 *  TODO:
 *    check if SIGSEGV handler works for all registers (including FP!)
 */

#include <unistd.h>
#include <fcntl.h>
#include <time.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <pthread.h>
#include <sys/mman.h>
#include <sys/ipc.h>
#include <sys/shm.h>
#include <signal.h>

#include "sysdeps.h"
#include "main.h"
#include "version.h"
#include "prefs.h"
#include "prefs_editor.h"
#include "cpu_emulation.h"
#include "emul_op.h"
#include "xlowmem.h"
#include "xpram.h"
#include "timer.h"
#include "adb.h"
#include "video.h"
#include "sys.h"
#include "macos_util.h"
#include "rom_patches.h"
#include "user_strings.h"
#include "vm_alloc.h"
#include "sigsegv.h"

#define DEBUG 0
#include "debug.h"


#ifdef HAVE_DIRENT_H
#include <dirent.h>
#endif

#ifdef USE_SDL
#include <SDL.h>
#endif

#ifndef USE_SDL_VIDEO
#include <X11/Xlib.h>
#endif

#ifdef ENABLE_GTK
#include <gtk/gtk.h>
#endif

#ifdef ENABLE_XF86_DGA
#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <X11/extensions/xf86dga.h>
#endif

#ifdef ENABLE_MON
#include "mon.h"
#endif


// Enable emulation of unaligned lmw/stmw?
#define EMULATE_UNALIGNED_LOADSTORE_MULTIPLE 1

// Enable Execute68k() safety checks?
#define SAFE_EXEC_68K 0

// Interrupts in EMUL_OP mode?
#define INTERRUPTS_IN_EMUL_OP_MODE 1

// Interrupts in native mode?
#define INTERRUPTS_IN_NATIVE_MODE 1


// Constants
const char ROM_FILE_NAME[] = "ROM";
const char ROM_FILE_NAME2[] = "Mac OS ROM";

#if REAL_ADDRESSING
const uintptr RAM_BASE = 0x20000000;            // Base address of RAM
#else
// FIXME: needs to be >= 0x04000000
const uintptr RAM_BASE = 0x10000000;            // Base address of RAM
#endif
const uint32 SIG_STACK_SIZE = 0x10000;          // Size of signal stack


#if !EMULATED_PPC
struct sigregs {
        uint32 nip;
        uint32 link;
        uint32 ctr;
        uint32 msr;
        uint32 xer;
        uint32 ccr;
        uint32 gpr[32];
};

#if defined(__linux__)
#include <sys/ucontext.h>
#define MACHINE_REGISTERS(scp)  ((machine_regs *)(((ucontext_t *)scp)->uc_mcontext.regs))

struct machine_regs : public pt_regs
{
        u_long & cr()                           { return pt_regs::ccr; }
        uint32 cr() const                       { return pt_regs::ccr; }
        uint32 lr() const                       { return pt_regs::link; }
        uint32 ctr() const                      { return pt_regs::ctr; }
        uint32 xer() const                      { return pt_regs::xer; }
        uint32 msr() const                      { return pt_regs::msr; }
        uint32 dar() const                      { return pt_regs::dar; }
        u_long & pc()                           { return pt_regs::nip; }
        uint32 pc() const                       { return pt_regs::nip; }
        u_long & gpr(int i)                     { return pt_regs::gpr[i]; }
        uint32 gpr(int i) const         { return pt_regs::gpr[i]; }
};
#endif

#if defined(__NetBSD__)
#include <sys/ucontext.h>
#define MACHINE_REGISTERS(scp)  ((machine_regs *)&(((ucontext_t *)scp)->uc_mcontext))

struct machine_regs : public mcontext_t
{
        long & cr()                                     { return __gregs[_REG_CR]; }
        uint32 cr() const                       { return __gregs[_REG_CR]; }
        uint32 lr() const                       { return __gregs[_REG_LR]; }
        uint32 ctr() const                      { return __gregs[_REG_CTR]; }
        uint32 xer() const                      { return __gregs[_REG_XER]; }
        uint32 msr() const                      { return __gregs[_REG_MSR]; }
        uint32 dar() const                      { return (uint32)(((siginfo_t *)(((unsigned long)this) - offsetof(ucontext_t, uc_mcontext))) - 1)->si_addr; } /* HACK */
        long & pc()                                     { return __gregs[_REG_PC]; }
        uint32 pc() const                       { return __gregs[_REG_PC]; }
        long & gpr(int i)                       { return __gregs[_REG_R0 + i]; }
        uint32 gpr(int i) const         { return __gregs[_REG_R0 + i]; }
};
#endif

#if defined(__APPLE__) && defined(__MACH__)
#include <sys/signal.h>
extern "C" int sigaltstack(const struct sigaltstack *ss, struct sigaltstack *oss);

#include <sys/ucontext.h>
#define MACHINE_REGISTERS(scp)  ((machine_regs *)(((ucontext_t *)scp)->uc_mcontext))

struct machine_regs : public mcontext
{
        uint32 & cr()                           { return ss.cr; }
        uint32 cr() const                       { return ss.cr; }
        uint32 lr() const                       { return ss.lr; }
        uint32 ctr() const                      { return ss.ctr; }
        uint32 xer() const                      { return ss.xer; }
        uint32 msr() const                      { return ss.srr1; }
        uint32 dar() const                      { return es.dar; }
        uint32 & pc()                           { return ss.srr0; }
        uint32 pc() const                       { return ss.srr0; }
        uint32 & gpr(int i)                     { return (&ss.r0)[i]; }
        uint32 gpr(int i) const         { return (&ss.r0)[i]; }
};
#endif

static void build_sigregs(sigregs *srp, machine_regs *mrp)
{
        srp->nip = mrp->pc();
        srp->link = mrp->lr();
        srp->ctr = mrp->ctr();
        srp->msr = mrp->msr();
        srp->xer = mrp->xer();
        srp->ccr = mrp->cr();
        for (int i = 0; i < 32; i++)
                srp->gpr[i] = mrp->gpr(i);
}
#endif


// Global variables (exported)
#if !EMULATED_PPC
void *TOC = NULL;                       // Pointer to Thread Local Storage (r2)
void *R13 = NULL;                       // Pointer to .sdata section (r13 under Linux)
#endif
uint32 RAMBase;                 // Base address of Mac RAM
uint32 RAMSize;                 // Size of Mac RAM
uint32 KernelDataAddr;  // Address of Kernel Data
uint32 BootGlobsAddr;   // Address of BootGlobs structure at top of Mac RAM
uint32 DRCacheAddr;             // Address of DR Cache
uint32 PVR;                             // Theoretical PVR
int64 CPUClockSpeed;    // Processor clock speed (Hz)
int64 BusClockSpeed;    // Bus clock speed (Hz)
int64 TimebaseSpeed;    // Timebase clock speed (Hz)
uint8 *RAMBaseHost;             // Base address of Mac RAM (host address space)
uint8 *ROMBaseHost;             // Base address of Mac ROM (host address space)


// Global variables
#ifndef USE_SDL_VIDEO
char *x_display_name = NULL;                            // X11 display name
Display *x_display = NULL;                                      // X11 display handle
#ifdef X11_LOCK_TYPE
X11_LOCK_TYPE x_display_lock = X11_LOCK_INIT; // X11 display lock
#endif
#endif

static int zero_fd = 0;                                         // FD of /dev/zero
static bool lm_area_mapped = false;                     // Flag: Low Memory area mmap()ped
static int kernel_area = -1;                            // SHM ID of Kernel Data area
static bool rom_area_mapped = false;            // Flag: Mac ROM mmap()ped
static bool ram_area_mapped = false;            // Flag: Mac RAM mmap()ped
static bool dr_cache_area_mapped = false;       // Flag: Mac DR Cache mmap()ped
static bool dr_emulator_area_mapped = false;// Flag: Mac DR Emulator mmap()ped
static KernelData *kernel_data;                         // Pointer to Kernel Data
static EmulatorData *emulator_data;

static uint8 last_xpram[XPRAM_SIZE];            // Buffer for monitoring XPRAM changes

static bool nvram_thread_active = false;        // Flag: NVRAM watchdog installed
static volatile bool nvram_thread_cancel;       // Flag: Cancel NVRAM thread
static pthread_t nvram_thread;                          // NVRAM watchdog
static bool tick_thread_active = false;         // Flag: MacOS thread installed
static volatile bool tick_thread_cancel;        // Flag: Cancel 60Hz thread
static pthread_t tick_thread;                           // 60Hz thread
static pthread_t emul_thread;                           // MacOS thread

static bool ready_for_signals = false;          // Handler installed, signals can be sent
static int64 num_segv = 0;                                      // Number of handled SEGV signals

static struct sigaction sigusr2_action;         // Interrupt signal (of emulator thread)
#if EMULATED_PPC
static uintptr sig_stack = 0;                           // Stack for PowerPC interrupt routine
#else
static struct sigaction sigsegv_action;         // Data access exception signal (of emulator thread)
static struct sigaction sigill_action;          // Illegal instruction signal (of emulator thread)
static struct sigaltstack sig_stack;            // Stack for signal handlers
static struct sigaltstack extra_stack;          // Stack for SIGSEGV inside interrupt handler
static bool emul_thread_fatal = false;          // Flag: MacOS thread crashed, tick thread shall dump debug output
static sigregs sigsegv_regs;                            // Register dump when crashed
static const char *crash_reason = NULL;         // Reason of the crash (SIGSEGV, SIGBUS, SIGILL)
#endif

uint32  SheepMem::page_size;                            // Size of a native page
uintptr SheepMem::zero_page = 0;                        // Address of ro page filled in with zeros
uintptr SheepMem::base = 0x60000000;            // Address of SheepShaver data
uintptr SheepMem::proc;                                         // Bottom address of SheepShave procedures
uintptr SheepMem::data;                                         // Top of SheepShaver data (stack like storage)


// Prototypes
static bool kernel_data_init(void);
static void kernel_data_exit(void);
static void Quit(void);
static void *emul_func(void *arg);
static void *nvram_func(void *arg);
static void *tick_func(void *arg);
#if EMULATED_PPC
extern void emul_ppc(uint32 start);
extern void init_emul_ppc(void);
extern void exit_emul_ppc(void);
sigsegv_return_t sigsegv_handler(sigsegv_address_t, sigsegv_address_t);
#else
extern "C" void sigusr2_handler_init(int sig, siginfo_t *sip, void *scp);
extern "C" void sigusr2_handler(int sig, siginfo_t *sip, void *scp);
static void sigsegv_handler(int sig, siginfo_t *sip, void *scp);
static void sigill_handler(int sig, siginfo_t *sip, void *scp);
#endif


// From asm_linux.S
#if !EMULATED_PPC
extern "C" void *get_sp(void);
extern "C" void *get_r2(void);
extern "C" void set_r2(void *);
extern "C" void *get_r13(void);
extern "C" void set_r13(void *);
extern "C" void flush_icache_range(uint32 start, uint32 end);
extern "C" void jump_to_rom(uint32 entry, uint32 context);
extern "C" void quit_emulator(void);
extern "C" void execute_68k(uint32 pc, M68kRegisters *r);
extern "C" void ppc_interrupt(uint32 entry, uint32 kernel_data);
extern "C" int atomic_add(int *var, int v);
extern "C" int atomic_and(int *var, int v);
extern "C" int atomic_or(int *var, int v);
extern void paranoia_check(void);
#endif


#if EMULATED_PPC
/*
 *  Return signal stack base
 */

uintptr SignalStackBase(void)
{
        return sig_stack + SIG_STACK_SIZE;
}


/*
 *  Atomic operations
 */

#if HAVE_SPINLOCKS
static spinlock_t atomic_ops_lock = SPIN_LOCK_UNLOCKED;
#else
#define spin_lock(LOCK)
#define spin_unlock(LOCK)
#endif

int atomic_add(int *var, int v)
{
        spin_lock(&atomic_ops_lock);
        int ret = *var;
        *var += v;
        spin_unlock(&atomic_ops_lock);
        return ret;
}

int atomic_and(int *var, int v)
{
        spin_lock(&atomic_ops_lock);
        int ret = *var;
        *var &= v;
        spin_unlock(&atomic_ops_lock);
        return ret;
}

int atomic_or(int *var, int v)
{
        spin_lock(&atomic_ops_lock);
        int ret = *var;
        *var |= v;
        spin_unlock(&atomic_ops_lock);
        return ret;
}
#endif


/*
 *  Memory management helpers
 */

static inline int vm_mac_acquire(uint32 addr, uint32 size)
{
        return vm_acquire_fixed(Mac2HostAddr(addr), size);
}

static inline int vm_mac_release(uint32 addr, uint32 size)
{
        return vm_release(Mac2HostAddr(addr), size);
}


/*
 *  Main program
 */

static void usage(const char *prg_name)
{
        printf("Usage: %s [OPTION...]\n", prg_name);
        printf("\nUnix options:\n");
        printf("  --display STRING\n    X display to use\n");
        PrefsPrintUsage();
        exit(0);
}

int main(int argc, char **argv)
{
        char str[256];
        int rom_fd;
        FILE *proc_file;
        const char *rom_path;
        uint32 rom_size, actual;
        uint8 *rom_tmp;
        time_t now, expire;

        // Initialize variables
        RAMBase = 0;
        tzset();

        // Print some info
        printf(GetString(STR_ABOUT_TEXT1), VERSION_MAJOR, VERSION_MINOR);
        printf(" %s\n", GetString(STR_ABOUT_TEXT2));

#if !EMULATED_PPC
#ifdef SYSTEM_CLOBBERS_R2
        // Get TOC pointer
        TOC = get_r2();
#endif
#ifdef SYSTEM_CLOBBERS_R13
        // Get r13 register
        R13 = get_r13();
#endif
#endif

#ifdef ENABLE_GTK
        // Init GTK
        gtk_set_locale();
        gtk_init(&argc, &argv);
#endif

        // Read preferences
        PrefsInit(argc, argv);

        // Parse command line arguments
        for (int i=1; i<argc; i++) {
                if (strcmp(argv[i], "--help") == 0) {
                        usage(argv[0]);
#ifndef USE_SDL_VIDEO
                } else if (strcmp(argv[i], "--display") == 0) {
                        i++;
                        if (i < argc)
                                x_display_name = strdup(argv[i]);
#endif
                } else if (argv[i][0] == '-') {
                        fprintf(stderr, "Unrecognized option '%s'\n", argv[i]);
                        usage(argv[0]);
                }
        }

#ifdef USE_SDL
        // Initialize SDL system
        int sdl_flags = 0;
#ifdef USE_SDL_VIDEO
        sdl_flags |= SDL_INIT_VIDEO;
#endif
#ifdef USE_SDL_AUDIO
        sdl_flags |= SDL_INIT_AUDIO;
#endif
        assert(sdl_flags != 0);
        if (SDL_Init(sdl_flags) == -1) {
                char str[256];
                sprintf(str, "Could not initialize SDL: %s.\n", SDL_GetError());
                ErrorAlert(str);
                goto quit;
        }
        atexit(SDL_Quit);
#endif

#ifndef USE_SDL_VIDEO
        // Open display
        x_display = XOpenDisplay(x_display_name);
        if (x_display == NULL) {
                char str[256];
                sprintf(str, GetString(STR_NO_XSERVER_ERR), XDisplayName(x_display_name));
                ErrorAlert(str);
                goto quit;
        }

#if defined(ENABLE_XF86_DGA) && !defined(ENABLE_MON)
        // Fork out, so we can return from fullscreen mode when things get ugly
        XF86DGAForkApp(DefaultScreen(x_display));
#endif
#endif

#ifdef ENABLE_MON
        // Initialize mon
        mon_init();
#endif

#if !EMULATED_PPC
        // Create and install stacks for signal handlers
        sig_stack.ss_sp = malloc(SIG_STACK_SIZE);
        D(bug("Signal stack at %p\n", sig_stack.ss_sp));
        if (sig_stack.ss_sp == NULL) {
                ErrorAlert(GetString(STR_NOT_ENOUGH_MEMORY_ERR));
                goto quit;
        }
        sig_stack.ss_flags = 0;
        sig_stack.ss_size = SIG_STACK_SIZE;
        if (sigaltstack(&sig_stack, NULL) < 0) {
                sprintf(str, GetString(STR_SIGALTSTACK_ERR), strerror(errno));
                ErrorAlert(str);
                goto quit;
        }
        extra_stack.ss_sp = malloc(SIG_STACK_SIZE);
        D(bug("Extra stack at %p\n", extra_stack.ss_sp));
        if (extra_stack.ss_sp == NULL) {
                ErrorAlert(GetString(STR_NOT_ENOUGH_MEMORY_ERR));
                goto quit;
        }
        extra_stack.ss_flags = 0;
        extra_stack.ss_size = SIG_STACK_SIZE;
#endif

#if !EMULATED_PPC
        // Install SIGSEGV and SIGBUS handlers
        sigemptyset(&sigsegv_action.sa_mask);   // Block interrupts during SEGV handling
        sigaddset(&sigsegv_action.sa_mask, SIGUSR2);
        sigsegv_action.sa_sigaction = sigsegv_handler;
        sigsegv_action.sa_flags = SA_ONSTACK | SA_SIGINFO;
#ifdef HAVE_SIGNAL_SA_RESTORER
        sigsegv_action.sa_restorer = NULL;
#endif
        if (sigaction(SIGSEGV, &sigsegv_action, NULL) < 0) {
                sprintf(str, GetString(STR_SIGSEGV_INSTALL_ERR), strerror(errno));
                ErrorAlert(str);
                goto quit;
        }
        if (sigaction(SIGBUS, &sigsegv_action, NULL) < 0) {
                sprintf(str, GetString(STR_SIGSEGV_INSTALL_ERR), strerror(errno));
                ErrorAlert(str);
                goto quit;
        }
#else
        // Install SIGSEGV handler for CPU emulator
        if (!sigsegv_install_handler(sigsegv_handler)) {
                sprintf(str, GetString(STR_SIGSEGV_INSTALL_ERR), strerror(errno));
                ErrorAlert(str);
                goto quit;
        }
#endif

        // Initialize VM system
        vm_init();

        // Get system info
        PVR = 0x00040000;                       // Default: 604
        CPUClockSpeed = 100000000;      // Default: 100MHz
        BusClockSpeed = 100000000;      // Default: 100MHz
        TimebaseSpeed =  25000000;      // Default:  25MHz
#if EMULATED_PPC
        PVR = 0x000c0000;                       // Default: 7400 (with AltiVec)
#elif defined(__APPLE__) && defined(__MACH__)
        proc_file = popen("ioreg -c IOPlatformDevice", "r");
        if (proc_file) {
                char line[256];
                bool powerpc_node = false;
                while (fgets(line, sizeof(line) - 1, proc_file)) {
                        // Read line
                        int len = strlen(line);
                        if (len == 0)
                                continue;
                        line[len - 1] = 0;

                        // Parse line
                        if (strstr(line, "o PowerPC,"))
                                powerpc_node = true;
                        else if (powerpc_node) {
                                uint32 value;
                                char head[256];
                                if (sscanf(line, "%[ |]\"cpu-version\" = <%x>", head, &value) == 2)
                                        PVR = value;
                                else if (sscanf(line, "%[ |]\"clock-frequency\" = <%x>", head, &value) == 2)
                                        CPUClockSpeed = value;
                                else if (sscanf(line, "%[ |]\"bus-frequency\" = <%x>", head, &value) == 2)
                                        BusClockSpeed = value;
                                else if (sscanf(line, "%[ |]\"timebase-frequency\" = <%x>", head, &value) == 2)
                                        TimebaseSpeed = value;
                                else if (strchr(line, '}'))
                                        powerpc_node = false;
                        }
                }
                fclose(proc_file);
        } else {
                sprintf(str, GetString(STR_PROC_CPUINFO_WARN), strerror(errno));
                WarningAlert(str);
        }
#else
        proc_file = fopen("/proc/cpuinfo", "r");
        if (proc_file) {
                // CPU specs from Linux kernel
                // TODO: make it more generic with features (e.g. AltiVec) and
                // cache information and friends for NameRegistry
                static const struct {
                        uint32 pvr_mask;
                        uint32 pvr_value;
                        const char *cpu_name;
                }
                cpu_specs[] = {
                        { 0xffff0000, 0x00010000, "601" },
                        { 0xffff0000, 0x00030000, "603" },
                        { 0xffff0000, 0x00060000, "603e" },
                        { 0xffff0000, 0x00070000, "603ev" },
                        { 0xffff0000, 0x00040000, "604" },
                        { 0xfffff000, 0x00090000, "604e" },
                        { 0xffff0000, 0x00090000, "604r" },
                        { 0xffff0000, 0x000a0000, "604ev" },
                        { 0xffffffff, 0x00084202, "740/750" },
                        { 0xfffff000, 0x00083000, "745/755" },
                        { 0xfffffff0, 0x00080100, "750CX" },
                        { 0xfffffff0, 0x00082200, "750CX" },
                        { 0xfffffff0, 0x00082210, "750CXe" },
                        { 0xffffff00, 0x70000100, "750FX" },
                        { 0xffffffff, 0x70000200, "750FX" },
                        { 0xffff0000, 0x70000000, "750FX" },
                        { 0xffff0000, 0x70020000, "750GX" },
                        { 0xffff0000, 0x00080000, "740/750" },
                        { 0xffffffff, 0x000c1101, "7400 (1.1)" },
                        { 0xffff0000, 0x000c0000, "7400" },
                        { 0xffff0000, 0x800c0000, "7410" },
                        { 0xffffffff, 0x80000200, "7450" },
                        { 0xffffffff, 0x80000201, "7450" },
                        { 0xffff0000, 0x80000000, "7450" },
                        { 0xffffff00, 0x80010100, "7455" },
                        { 0xffffffff, 0x80010200, "7455" },
                        { 0xffff0000, 0x80010000, "7455" },
                        { 0xffff0000, 0x80020000, "7457" },
                        { 0xffff0000, 0x80030000, "7447A" },
                        { 0x7fff0000, 0x00810000, "82xx" },
                        { 0x7fff0000, 0x00820000, "8280" },
                        { 0xffff0000, 0x00400000, "Power3 (630)" },
                        { 0xffff0000, 0x00410000, "Power3 (630+)" },
                        { 0xffff0000, 0x00360000, "I-star" },
                        { 0xffff0000, 0x00370000, "S-star" },
                        { 0xffff0000, 0x00350000, "Power4" },
                        { 0xffff0000, 0x00390000, "PPC970" },
                        { 0xffff0000, 0x003a0000, "POWER5" },
                        { 0, 0, 0 }
                };

                char line[256];
                while(fgets(line, 255, proc_file)) {
                        // Read line
                        int len = strlen(line);
                        if (len == 0)
                                continue;
                        line[len-1] = 0;

                        // Parse line
                        int i;
                        char value[256];
                        if (sscanf(line, "cpu : %[0-9A-Za-a]", value) == 1) {
                                // Search by name
                                const char *cpu_name = NULL;
                                for (int i = 0; cpu_specs[i].pvr_mask != 0; i++) {
                                        if (strcmp(cpu_specs[i].cpu_name, value) == 0) {
                                                cpu_name = cpu_specs[i].cpu_name;
                                                PVR = cpu_specs[i].pvr_value;
                                                break;
                                        }
                                }
                                if (cpu_name == NULL)
                                        printf("WARNING: Unknown CPU type '%s', assuming 604\n", value);
                                else
                                        printf("Found a PowerPC %s processor\n", cpu_name);
                        }
                        if (sscanf(line, "clock : %dMHz", &i) == 1)
                                CPUClockSpeed = BusClockSpeed = i * 1000000;
                }
                fclose(proc_file);
        } else {
                sprintf(str, GetString(STR_PROC_CPUINFO_WARN), strerror(errno));
                WarningAlert(str);
        }

        // Get actual bus frequency
        proc_file = fopen("/proc/device-tree/clock-frequency", "r");
        if (proc_file) {
                union { uint8 b[4]; uint32 l; } value;
                if (fread(value.b, sizeof(value), 1, proc_file) == 1)
                        BusClockSpeed = value.l;
                fclose(proc_file);
        }

        // Get actual timebase frequency
        TimebaseSpeed = BusClockSpeed / 4;
        DIR *cpus_dir;
        if ((cpus_dir = opendir("/proc/device-tree/cpus")) != NULL) {
                struct dirent *cpu_entry;
                while ((cpu_entry = readdir(cpus_dir)) != NULL) {
                        if (strstr(cpu_entry->d_name, "PowerPC,") == cpu_entry->d_name) {
                                char timebase_freq_node[256];
                                sprintf(timebase_freq_node, "/proc/device-tree/cpus/%s/timebase-frequency", cpu_entry->d_name);
                                proc_file = fopen(timebase_freq_node, "r");
                                if (proc_file) {
                                        union { uint8 b[4]; uint32 l; } value;
                                        if (fread(value.b, sizeof(value), 1, proc_file) == 1)
                                                TimebaseSpeed = value.l;
                                        fclose(proc_file);
                                }
                        }
                }
                closedir(cpus_dir);
        }
#endif
        // Remap any newer G4/G5 processor to plain G4 for compatibility
        switch (PVR >> 16) {
        case 0x8000:                            // 7450
        case 0x8001:                            // 7455
        case 0x8002:                            // 7457
        case 0x0039:                            //  970
                PVR = 0x000c0000;               // 7400
                break;
        }
        D(bug("PVR: %08x (assumed)\n", PVR));

        // Init system routines
        SysInit();

        // Show preferences editor
        if (!PrefsFindBool("nogui"))
                if (!PrefsEditor())
                        goto quit;

#if !EMULATED_PPC
        // Check some things
        paranoia_check();
#endif

        // Open /dev/zero
        zero_fd = open("/dev/zero", O_RDWR);
        if (zero_fd < 0) {
                sprintf(str, GetString(STR_NO_DEV_ZERO_ERR), strerror(errno));
                ErrorAlert(str);
                goto quit;
        }

#ifndef PAGEZERO_HACK
        // Create Low Memory area (0x0000..0x3000)
        if (vm_mac_acquire(0, 0x3000) < 0) {
                sprintf(str, GetString(STR_LOW_MEM_MMAP_ERR), strerror(errno));
                ErrorAlert(str);
                goto quit;
        }
        lm_area_mapped = true;
#endif

        // Create areas for Kernel Data
        if (!kernel_data_init())
                goto quit;
        kernel_data = (KernelData *)Mac2HostAddr(KERNEL_DATA_BASE);
        emulator_data = &kernel_data->ed;
        KernelDataAddr = KERNEL_DATA_BASE;
        D(bug("Kernel Data at %p (%08x)\n", kernel_data, KERNEL_DATA_BASE));
        D(bug("Emulator Data at %p (%08x)\n", emulator_data, KERNEL_DATA_BASE + offsetof(KernelData, ed)));

        // Create area for DR Cache
        if (vm_mac_acquire(DR_EMULATOR_BASE, DR_EMULATOR_SIZE) < 0) {
                sprintf(str, GetString(STR_DR_EMULATOR_MMAP_ERR), strerror(errno));
                ErrorAlert(str);
                goto quit;
        }
        dr_emulator_area_mapped = true;
        if (vm_mac_acquire(DR_CACHE_BASE, DR_CACHE_SIZE) < 0) {
                sprintf(str, GetString(STR_DR_CACHE_MMAP_ERR), strerror(errno));
                ErrorAlert(str);
                goto quit;
        }
        dr_cache_area_mapped = true;
#if !EMULATED_PPC
        if (vm_protect((char *)DR_CACHE_BASE, DR_CACHE_SIZE, VM_PAGE_READ | VM_PAGE_WRITE | VM_PAGE_EXECUTE) < 0) {
                sprintf(str, GetString(STR_DR_CACHE_MMAP_ERR), strerror(errno));
                ErrorAlert(str);
                goto quit;
        }
#endif
        DRCacheAddr = DR_CACHE_BASE;
        D(bug("DR Cache at %p\n", DRCacheAddr));

        // Create area for SheepShaver data
        if (!SheepMem::Init()) {
                sprintf(str, GetString(STR_SHEEP_MEM_MMAP_ERR), strerror(errno));
                ErrorAlert(str);
                goto quit;
        }

        // Create area for Mac ROM
        if (vm_mac_acquire(ROM_BASE, ROM_AREA_SIZE) < 0) {
                sprintf(str, GetString(STR_ROM_MMAP_ERR), strerror(errno));
                ErrorAlert(str);
                goto quit;
        }
        ROMBaseHost = Mac2HostAddr(ROM_BASE);
#if !EMULATED_PPC
        if (vm_protect(ROMBaseHost, ROM_AREA_SIZE, VM_PAGE_READ | VM_PAGE_WRITE | VM_PAGE_EXECUTE) < 0) {
                sprintf(str, GetString(STR_ROM_MMAP_ERR), strerror(errno));
                ErrorAlert(str);
                goto quit;
        }
#endif
        rom_area_mapped = true;
        D(bug("ROM area at %p (%08x)\n", ROMBaseHost, ROM_BASE));

        // Create area for Mac RAM
        RAMSize = PrefsFindInt32("ramsize");
        if (RAMSize < 8*1024*1024) {
                WarningAlert(GetString(STR_SMALL_RAM_WARN));
                RAMSize = 8*1024*1024;
        }

        if (vm_mac_acquire(RAM_BASE, RAMSize) < 0) {
                sprintf(str, GetString(STR_RAM_MMAP_ERR), strerror(errno));
                ErrorAlert(str);
                goto quit;
        }
        RAMBaseHost = Mac2HostAddr(RAM_BASE);
#if !EMULATED_PPC
        if (vm_protect(RAMBaseHost, RAMSize, VM_PAGE_READ | VM_PAGE_WRITE | VM_PAGE_EXECUTE) < 0) {
                sprintf(str, GetString(STR_RAM_MMAP_ERR), strerror(errno));
                ErrorAlert(str);
                goto quit;
        }
#endif
        RAMBase = RAM_BASE;
        ram_area_mapped = true;
        D(bug("RAM area at %p (%08x)\n", RAMBaseHost, RAMBase));

        if (RAMBase > ROM_BASE) {
                ErrorAlert(GetString(STR_RAM_HIGHER_THAN_ROM_ERR));
                goto quit;
        }

        // Load Mac ROM
        rom_path = PrefsFindString("rom");
        rom_fd = open(rom_path ? rom_path : ROM_FILE_NAME, O_RDONLY);
        if (rom_fd < 0) {
                rom_fd = open(rom_path ? rom_path : ROM_FILE_NAME2, O_RDONLY);
                if (rom_fd < 0) {
                        ErrorAlert(GetString(STR_NO_ROM_FILE_ERR));
                        goto quit;
                }
        }
        printf(GetString(STR_READING_ROM_FILE));
        rom_size = lseek(rom_fd, 0, SEEK_END);
        lseek(rom_fd, 0, SEEK_SET);
        rom_tmp = new uint8[ROM_SIZE];
        actual = read(rom_fd, (void *)rom_tmp, ROM_SIZE);
        close(rom_fd);
        
        // Decode Mac ROM
        if (!DecodeROM(rom_tmp, actual)) {
                if (rom_size != 4*1024*1024) {
                        ErrorAlert(GetString(STR_ROM_SIZE_ERR));
                        goto quit;
                } else {
                        ErrorAlert(GetString(STR_ROM_FILE_READ_ERR));
                        goto quit;
                }
        }
        delete[] rom_tmp;

        // Initialize everything
        if (!InitAll())
                goto quit;
        D(bug("Initialization complete\n"));

        // Clear caches (as we loaded and patched code) and write protect ROM
#if !EMULATED_PPC
        flush_icache_range(ROM_BASE, ROM_BASE + ROM_AREA_SIZE);
#endif
        vm_protect(ROMBaseHost, ROM_AREA_SIZE, VM_PAGE_READ | VM_PAGE_EXECUTE);

        // Start 60Hz thread
        tick_thread_cancel = false;
        tick_thread_active = (pthread_create(&tick_thread, NULL, tick_func, NULL) == 0);
        D(bug("Tick thread installed (%ld)\n", tick_thread));

        // Start NVRAM watchdog thread
        memcpy(last_xpram, XPRAM, XPRAM_SIZE);
        nvram_thread_cancel = false;
        nvram_thread_active = (pthread_create(&nvram_thread, NULL, nvram_func, NULL) == 0);
        D(bug("NVRAM thread installed (%ld)\n", nvram_thread));

#if !EMULATED_PPC
        // Install SIGILL handler
        sigemptyset(&sigill_action.sa_mask);    // Block interrupts during ILL handling
        sigaddset(&sigill_action.sa_mask, SIGUSR2);
        sigill_action.sa_sigaction = sigill_handler;
        sigill_action.sa_flags = SA_ONSTACK | SA_SIGINFO;
#ifdef HAVE_SIGNAL_SA_RESTORER
        sigill_action.sa_restorer = NULL;
#endif
        if (sigaction(SIGILL, &sigill_action, NULL) < 0) {
                sprintf(str, GetString(STR_SIGILL_INSTALL_ERR), strerror(errno));
                ErrorAlert(str);
                goto quit;
        }
#endif

#if !EMULATED_PPC
        // Install interrupt signal handler
        sigemptyset(&sigusr2_action.sa_mask);
        sigusr2_action.sa_sigaction = sigusr2_handler_init;
        sigusr2_action.sa_flags = SA_ONSTACK | SA_RESTART | SA_SIGINFO;
#ifdef HAVE_SIGNAL_SA_RESTORER
        sigusr2_action.sa_restorer = NULL;
#endif
        if (sigaction(SIGUSR2, &sigusr2_action, NULL) < 0) {
                sprintf(str, GetString(STR_SIGUSR2_INSTALL_ERR), strerror(errno));
                ErrorAlert(str);
                goto quit;
        }
#endif

        // Get my thread ID and execute MacOS thread function
        emul_thread = pthread_self();
        D(bug("MacOS thread is %ld\n", emul_thread));
        emul_func(NULL);

quit:
        Quit();
        return 0;
}


/*
 *  Cleanup and quit
 */

static void Quit(void)
{
#if EMULATED_PPC
        // Exit PowerPC emulation
        exit_emul_ppc();
#endif

        // Stop 60Hz thread
        if (tick_thread_active) {
                tick_thread_cancel = true;
                pthread_cancel(tick_thread);
                pthread_join(tick_thread, NULL);
        }

        // Stop NVRAM watchdog thread
        if (nvram_thread_active) {
                nvram_thread_cancel = true;
                pthread_cancel(nvram_thread);
                pthread_join(nvram_thread, NULL);
        }

#if !EMULATED_PPC
        // Uninstall SIGSEGV and SIGBUS handlers
        sigemptyset(&sigsegv_action.sa_mask);
        sigsegv_action.sa_handler = SIG_DFL;
        sigsegv_action.sa_flags = 0;
        sigaction(SIGSEGV, &sigsegv_action, NULL);
        sigaction(SIGBUS, &sigsegv_action, NULL);

        // Uninstall SIGILL handler
        sigemptyset(&sigill_action.sa_mask);
        sigill_action.sa_handler = SIG_DFL;
        sigill_action.sa_flags = 0;
        sigaction(SIGILL, &sigill_action, NULL);

        // Delete stacks for signal handlers
        if (sig_stack.ss_sp)
                free(sig_stack.ss_sp);
        if (extra_stack.ss_sp)
                free(extra_stack.ss_sp);
#endif

        // Deinitialize everything
        ExitAll();

        // Delete SheepShaver globals
        SheepMem::Exit();

        // Delete RAM area
        if (ram_area_mapped)
                vm_mac_release(RAM_BASE, RAMSize);

        // Delete ROM area
        if (rom_area_mapped)
                vm_mac_release(ROM_BASE, ROM_AREA_SIZE);

        // Delete DR cache areas
        if (dr_emulator_area_mapped)
                vm_mac_release(DR_EMULATOR_BASE, DR_EMULATOR_SIZE);
        if (dr_cache_area_mapped)
                vm_mac_release(DR_CACHE_BASE, DR_CACHE_SIZE);

        // Delete Kernel Data area
        kernel_data_exit();

        // Delete Low Memory area
        if (lm_area_mapped)
                vm_mac_release(0, 0x3000);

        // Close /dev/zero
        if (zero_fd > 0)
                close(zero_fd);

        // Exit system routines
        SysExit();

        // Exit preferences
        PrefsExit();

#ifdef ENABLE_MON
        // Exit mon
        mon_exit();
#endif

        // Close X11 server connection
#ifndef USE_SDL_VIDEO
        if (x_display)
                XCloseDisplay(x_display);
#endif

        exit(0);
}


/*
 *  Initialize Kernel Data segments
 */

#if defined(__CYGWIN__)
#define WIN32_LEAN_AND_MEAN
#include <windows.h>

static HANDLE kernel_handle;                            // Shared memory handle for Kernel Data
static DWORD allocation_granule;                        // Minimum size of allocateable are (64K)
static DWORD kernel_area_size;                          // Size of Kernel Data area
#endif

static bool kernel_data_init(void)
{
        char str[256];
#ifdef _WIN32
        SYSTEM_INFO si;
        GetSystemInfo(&si);
        allocation_granule = si.dwAllocationGranularity;
        kernel_area_size = (KERNEL_AREA_SIZE + allocation_granule - 1) & -allocation_granule;

        char rcs[10];
        LPVOID kernel_addr;
        kernel_handle = CreateFileMapping(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0, kernel_area_size, NULL);
        if (kernel_handle == NULL) {
                sprintf(rcs, "%d", GetLastError());
                sprintf(str, GetString(STR_KD_SHMGET_ERR), rcs);
                ErrorAlert(str);
                return false;
        }
        kernel_addr = (LPVOID)Mac2HostAddr(KERNEL_DATA_BASE & -allocation_granule);
        if (MapViewOfFileEx(kernel_handle, FILE_MAP_READ | FILE_MAP_WRITE, 0, 0, kernel_area_size, kernel_addr) != kernel_addr) {
                sprintf(rcs, "%d", GetLastError());
                sprintf(str, GetString(STR_KD_SHMAT_ERR), rcs);
                ErrorAlert(str);
                return false;
        }
        kernel_addr = (LPVOID)Mac2HostAddr(KERNEL_DATA2_BASE & -allocation_granule);
        if (MapViewOfFileEx(kernel_handle, FILE_MAP_READ | FILE_MAP_WRITE, 0, 0, kernel_area_size, kernel_addr) != kernel_addr) {
                sprintf(rcs, "%d", GetLastError());
                sprintf(str, GetString(STR_KD2_SHMAT_ERR), rcs);
                ErrorAlert(str);
                return false;
        }
#else
        kernel_area = shmget(IPC_PRIVATE, KERNEL_AREA_SIZE, 0600);
        if (kernel_area == -1) {
                sprintf(str, GetString(STR_KD_SHMGET_ERR), strerror(errno));
                ErrorAlert(str);
                return false;
        }
        if (shmat(kernel_area, Mac2HostAddr(KERNEL_DATA_BASE), 0) < 0) {
                sprintf(str, GetString(STR_KD_SHMAT_ERR), strerror(errno));
                ErrorAlert(str);
                return false;
        }
        if (shmat(kernel_area, Mac2HostAddr(KERNEL_DATA2_BASE), 0) < 0) {
                sprintf(str, GetString(STR_KD2_SHMAT_ERR), strerror(errno));
                ErrorAlert(str);
                return false;
        }
#endif
        return true;
}


/*
 *  Deallocate Kernel Data segments
 */

static void kernel_data_exit(void)
{
#ifdef _WIN32
        if (kernel_handle) {
                UnmapViewOfFile(Mac2HostAddr(KERNEL_DATA_BASE & -allocation_granule));
                UnmapViewOfFile(Mac2HostAddr(KERNEL_DATA2_BASE & -allocation_granule));
                CloseHandle(kernel_handle);
        }
#else
        if (kernel_area >= 0) {
                shmdt(Mac2HostAddr(KERNEL_DATA_BASE));
                shmdt(Mac2HostAddr(KERNEL_DATA2_BASE));
                shmctl(kernel_area, IPC_RMID, NULL);
        }
#endif
}


/*
 *  Jump into Mac ROM, start 680x0 emulator
 */

#if EMULATED_PPC
void jump_to_rom(uint32 entry)
{
        init_emul_ppc();
        emul_ppc(entry);
}
#endif


/*
 *  Emulator thread function
 */

static void *emul_func(void *arg)
{
        // We're now ready to receive signals
        ready_for_signals = true;

        // Decrease priority, so more time-critical things like audio will work better
        nice(1);

        // Jump to ROM boot routine
        D(bug("Jumping to ROM\n"));
#if EMULATED_PPC
        jump_to_rom(ROM_BASE + 0x310000);
#else
        jump_to_rom(ROM_BASE + 0x310000, (uint32)emulator_data);
#endif
        D(bug("Returned from ROM\n"));

        // We're no longer ready to receive signals
        ready_for_signals = false;
        return NULL;
}


#if !EMULATED_PPC
/*
 *  Execute 68k subroutine (must be ended with RTS)
 *  This must only be called by the emul_thread when in EMUL_OP mode
 *  r->a[7] is unused, the routine runs on the caller's stack
 */

void Execute68k(uint32 pc, M68kRegisters *r)
{
#if SAFE_EXEC_68K
        if (ReadMacInt32(XLM_RUN_MODE) != MODE_EMUL_OP)
                printf("FATAL: Execute68k() not called from EMUL_OP mode\n");
        if (!pthread_equal(pthread_self(), emul_thread))
                printf("FATAL: Execute68k() not called from emul_thread\n");
#endif
        execute_68k(pc, r);
}


/*
 *  Execute 68k A-Trap from EMUL_OP routine
 *  r->a[7] is unused, the routine runs on the caller's stack
 */

void Execute68kTrap(uint16 trap, M68kRegisters *r)
{
        uint16 proc[2] = {trap, M68K_RTS};
        Execute68k((uint32)proc, r);
}
#endif


/*
 *  Quit emulator (cause return from jump_to_rom)
 */

void QuitEmulator(void)
{
#if EMULATED_PPC
        Quit();
#else
        quit_emulator();
#endif
}


/*
 *  Dump 68k registers
 */

void Dump68kRegs(M68kRegisters *r)
{
        // Display 68k registers
        for (int i=0; i<8; i++) {
                printf("d%d: %08x", i, r->d[i]);
                if (i == 3 || i == 7)
                        printf("\n");
                else
                        printf(", ");
        }
        for (int i=0; i<8; i++) {
                printf("a%d: %08x", i, r->a[i]);
                if (i == 3 || i == 7)
                        printf("\n");
                else
                        printf(", ");
        }
}


/*
 *  Make code executable
 */

void MakeExecutable(int dummy, uint32 start, uint32 length)
{
        if ((start >= ROM_BASE) && (start < (ROM_BASE + ROM_SIZE)))
                return;
#if EMULATED_PPC
        FlushCodeCache(start, start + length);
#else
        flush_icache_range(start, start + length);
#endif
}


/*
 *  NVRAM watchdog thread (saves NVRAM every minute)
 */

static void nvram_watchdog(void)
{
        if (memcmp(last_xpram, XPRAM, XPRAM_SIZE)) {
                memcpy(last_xpram, XPRAM, XPRAM_SIZE);
                SaveXPRAM();
        }
}

static void *nvram_func(void *arg)
{
        while (!nvram_thread_cancel) {
                for (int i=0; i<60 && !nvram_thread_cancel; i++)
                        Delay_usec(999999);             // Only wait 1 second so we quit promptly when nvram_thread_cancel becomes true
                nvram_watchdog();
        }
        return NULL;
}


/*
 *  60Hz thread (really 60.15Hz)
 */

static void *tick_func(void *arg)
{
        int tick_counter = 0;
        uint64 start = GetTicks_usec();
        int64 ticks = 0;
        uint64 next = GetTicks_usec();

        while (!tick_thread_cancel) {

                // Wait
                next += 16625;
                int64 delay = next - GetTicks_usec();
                if (delay > 0)
                        Delay_usec(delay);
                else if (delay < -16625)
                        next = GetTicks_usec();
                ticks++;

#if !EMULATED_PPC
                // Did we crash?
                if (emul_thread_fatal) {

                        // Yes, dump registers
                        sigregs *r = &sigsegv_regs;
                        char str[256];
                        if (crash_reason == NULL)
                                crash_reason = "SIGSEGV";
                        sprintf(str, "%s\n"
                                "   pc %08lx     lr %08lx    ctr %08lx    msr %08lx\n"
                                "  xer %08lx     cr %08lx  \n"
                                "   r0 %08lx     r1 %08lx     r2 %08lx     r3 %08lx\n"
                                "   r4 %08lx     r5 %08lx     r6 %08lx     r7 %08lx\n"
                                "   r8 %08lx     r9 %08lx    r10 %08lx    r11 %08lx\n"
                                "  r12 %08lx    r13 %08lx    r14 %08lx    r15 %08lx\n"
                                "  r16 %08lx    r17 %08lx    r18 %08lx    r19 %08lx\n"
                                "  r20 %08lx    r21 %08lx    r22 %08lx    r23 %08lx\n"
                                "  r24 %08lx    r25 %08lx    r26 %08lx    r27 %08lx\n"
                                "  r28 %08lx    r29 %08lx    r30 %08lx    r31 %08lx\n",
                                crash_reason,
                                r->nip, r->link, r->ctr, r->msr,
                                r->xer, r->ccr,
                                r->gpr[0], r->gpr[1], r->gpr[2], r->gpr[3],
                                r->gpr[4], r->gpr[5], r->gpr[6], r->gpr[7],
                                r->gpr[8], r->gpr[9], r->gpr[10], r->gpr[11],
                                r->gpr[12], r->gpr[13], r->gpr[14], r->gpr[15],
                                r->gpr[16], r->gpr[17], r->gpr[18], r->gpr[19],
                                r->gpr[20], r->gpr[21], r->gpr[22], r->gpr[23],
                                r->gpr[24], r->gpr[25], r->gpr[26], r->gpr[27],
                                r->gpr[28], r->gpr[29], r->gpr[30], r->gpr[31]);
                        printf(str);
                        VideoQuitFullScreen();

#ifdef ENABLE_MON
                        // Start up mon in real-mode
                        printf("Welcome to the sheep factory.\n");
                        char *arg[4] = {"mon", "-m", "-r", NULL};
                        mon(3, arg);
#endif
                        return NULL;
                }
#endif

                // Pseudo Mac 1Hz interrupt, update local time
                if (++tick_counter > 60) {
                        tick_counter = 0;
                        WriteMacInt32(0x20c, TimerDateTime());
                }

                // Trigger 60Hz interrupt
                if (ReadMacInt32(XLM_IRQ_NEST) == 0) {
                        SetInterruptFlag(INTFLAG_VIA);
                        TriggerInterrupt();
                }
        }

        uint64 end = GetTicks_usec();
        D(bug("%Ld ticks in %Ld usec = %f ticks/sec\n", ticks, end - start, ticks * 1000000.0 / (end - start)));
        return NULL;
}


/*
 *  Pthread configuration
 */

void Set_pthread_attr(pthread_attr_t *attr, int priority)
{
#ifdef HAVE_PTHREADS
        pthread_attr_init(attr);
#if defined(_POSIX_THREAD_PRIORITY_SCHEDULING)
        // Some of these only work for superuser
        if (geteuid() == 0) {
                pthread_attr_setinheritsched(attr, PTHREAD_EXPLICIT_SCHED);
                pthread_attr_setschedpolicy(attr, SCHED_FIFO);
                struct sched_param fifo_param;
                fifo_param.sched_priority = ((sched_get_priority_min(SCHED_FIFO) + 
                                              sched_get_priority_max(SCHED_FIFO)) / 2 +
                                             priority);
                pthread_attr_setschedparam(attr, &fifo_param);
        }
        if (pthread_attr_setscope(attr, PTHREAD_SCOPE_SYSTEM) != 0) {
#ifdef PTHREAD_SCOPE_BOUND_NP
            // If system scope is not available (eg. we're not running
            // with CAP_SCHED_MGT capability on an SGI box), try bound
            // scope.  It exposes pthread scheduling to the kernel,
            // without setting realtime priority.
            pthread_attr_setscope(attr, PTHREAD_SCOPE_BOUND_NP);
#endif
        }
#endif
#endif
}


/*
 *  Mutexes
 */

#ifdef HAVE_PTHREADS

struct B2_mutex {
        B2_mutex() { 
            pthread_mutexattr_t attr;
            pthread_mutexattr_init(&attr);
            // Initialize the mutex for priority inheritance --
            // required for accurate timing.
#if defined(HAVE_PTHREAD_MUTEXATTR_SETPROTOCOL) && !defined(__CYGWIN__)
            pthread_mutexattr_setprotocol(&attr, PTHREAD_PRIO_INHERIT);
#endif
#if defined(HAVE_PTHREAD_MUTEXATTR_SETTYPE) && defined(PTHREAD_MUTEX_NORMAL)
            pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_NORMAL);
#endif
#ifdef HAVE_PTHREAD_MUTEXATTR_SETPSHARED
            pthread_mutexattr_setpshared(&attr, PTHREAD_PROCESS_PRIVATE);
#endif
            pthread_mutex_init(&m, &attr);
            pthread_mutexattr_destroy(&attr);
        }
        ~B2_mutex() { 
            pthread_mutex_trylock(&m); // Make sure it's locked before
            pthread_mutex_unlock(&m);  // unlocking it.
            pthread_mutex_destroy(&m);
        }
        pthread_mutex_t m;
};

B2_mutex *B2_create_mutex(void)
{
        return new B2_mutex;
}

void B2_lock_mutex(B2_mutex *mutex)
{
        pthread_mutex_lock(&mutex->m);
}

void B2_unlock_mutex(B2_mutex *mutex)
{
        pthread_mutex_unlock(&mutex->m);
}

void B2_delete_mutex(B2_mutex *mutex)
{
        delete mutex;
}

#else

struct B2_mutex {
        int dummy;
};

B2_mutex *B2_create_mutex(void)
{
        return new B2_mutex;
}

void B2_lock_mutex(B2_mutex *mutex)
{
}

void B2_unlock_mutex(B2_mutex *mutex)
{
}

void B2_delete_mutex(B2_mutex *mutex)
{
        delete mutex;
}

#endif


/*
 *  Trigger signal USR2 from another thread
 */

#if !EMULATED_PPC
void TriggerInterrupt(void)
{
        if (ready_for_signals)
                pthread_kill(emul_thread, SIGUSR2);
}
#endif


/*
 *  Interrupt flags (must be handled atomically!)
 */

volatile uint32 InterruptFlags = 0;

void SetInterruptFlag(uint32 flag)
{
        atomic_or((int *)&InterruptFlags, flag);
}

void ClearInterruptFlag(uint32 flag)
{
        atomic_and((int *)&InterruptFlags, ~flag);
}


/*
 *  Disable interrupts
 */

void DisableInterrupt(void)
{
#if EMULATED_PPC
        WriteMacInt32(XLM_IRQ_NEST, int32(ReadMacInt32(XLM_IRQ_NEST)) + 1);
#else
        atomic_add((int *)XLM_IRQ_NEST, 1);
#endif
}


/*
 *  Enable interrupts
 */

void EnableInterrupt(void)
{
#if EMULATED_PPC
        WriteMacInt32(XLM_IRQ_NEST, int32(ReadMacInt32(XLM_IRQ_NEST)) - 1);
#else
        atomic_add((int *)XLM_IRQ_NEST, -1);
#endif
}


/*
 *  USR2 handler
 */

#if !EMULATED_PPC
void sigusr2_handler(int sig, siginfo_t *sip, void *scp)
{
        machine_regs *r = MACHINE_REGISTERS(scp);

#ifdef USE_SDL_VIDEO
        // We must fill in the events queue in the same thread that did call SDL_SetVideoMode()
        SDL_PumpEvents();
#endif

        // Do nothing if interrupts are disabled
        if (*(int32 *)XLM_IRQ_NEST > 0)
                return;

#ifdef SYSTEM_CLOBBERS_R2
        // Restore pointer to Thread Local Storage
        set_r2(TOC);
#endif
#ifdef SYSTEM_CLOBBERS_R13
        // Restore pointer to .sdata section
        set_r13(R13);
#endif

        // Disable MacOS stack sniffer
        WriteMacInt32(0x110, 0);

        // Interrupt action depends on current run mode
        switch (ReadMacInt32(XLM_RUN_MODE)) {
                case MODE_68K:
                        // 68k emulator active, trigger 68k interrupt level 1
                        WriteMacInt16(ntohl(kernel_data->v[0x67c >> 2]), 1);
                        r->cr() |= ntohl(kernel_data->v[0x674 >> 2]);
                        break;

#if INTERRUPTS_IN_NATIVE_MODE
                case MODE_NATIVE:
                        // 68k emulator inactive, in nanokernel?
                        if (r->gpr(1) != KernelDataAddr) {

                                // Set extra stack for SIGSEGV handler
                                sigaltstack(&extra_stack, NULL);
                                
                                // Prepare for 68k interrupt level 1
                                WriteMacInt16(ntohl(kernel_data->v[0x67c >> 2]), 1);
                                WriteMacInt32(ntohl(kernel_data->v[0x658 >> 2]) + 0xdc, ReadMacInt32(ntohl(kernel_data->v[0x658 >> 2]) + 0xdc) | ntohl(kernel_data->v[0x674 >> 2]));

                                // Execute nanokernel interrupt routine (this will activate the 68k emulator)
                                DisableInterrupt();
                                if (ROMType == ROMTYPE_NEWWORLD)
                                        ppc_interrupt(ROM_BASE + 0x312b1c, KernelDataAddr);
                                else
                                        ppc_interrupt(ROM_BASE + 0x312a3c, KernelDataAddr);

                                // Reset normal stack
                                sigaltstack(&sig_stack, NULL);
                        }
                        break;
#endif

#if INTERRUPTS_IN_EMUL_OP_MODE
                case MODE_EMUL_OP:
                        // 68k emulator active, within EMUL_OP routine, execute 68k interrupt routine directly when interrupt level is 0
                        if ((ReadMacInt32(XLM_68K_R25) & 7) == 0) {

                                // Set extra stack for SIGSEGV handler
                                sigaltstack(&extra_stack, NULL);
#if 1
                                // Execute full 68k interrupt routine
                                M68kRegisters r;
                                uint32 old_r25 = ReadMacInt32(XLM_68K_R25);     // Save interrupt level
                                WriteMacInt32(XLM_68K_R25, 0x21);                       // Execute with interrupt level 1
                                static const uint16 proc[] = {
                                        0x3f3c, 0x0000,         // move.w       #$0000,-(sp)    (fake format word)
                                        0x487a, 0x000a,         // pea          @1(pc)                  (return address)
                                        0x40e7,                         // move         sr,-(sp)                (saved SR)
                                        0x2078, 0x0064,         // move.l       $64,a0
                                        0x4ed0,                         // jmp          (a0)
                                        M68K_RTS                        // @1
                                };
                                Execute68k((uint32)proc, &r);
                                WriteMacInt32(XLM_68K_R25, old_r25);            // Restore interrupt level
#else
                                // Only update cursor
                                if (HasMacStarted()) {
                                        if (InterruptFlags & INTFLAG_VIA) {
                                                ClearInterruptFlag(INTFLAG_VIA);
                                                ADBInterrupt();
                                                ExecuteNative(NATIVE_VIDEO_VBL);
                                        }
                                }
#endif
                                // Reset normal stack
                                sigaltstack(&sig_stack, NULL);
                        }
                        break;
#endif
        }
}
#endif


/*
 *  SIGSEGV handler
 */

#if !EMULATED_PPC
static void sigsegv_handler(int sig, siginfo_t *sip, void *scp)
{
        machine_regs *r = MACHINE_REGISTERS(scp);

        // Get effective address
        uint32 addr = r->dar();
        
#ifdef SYSTEM_CLOBBERS_R2
        // Restore pointer to Thread Local Storage
        set_r2(TOC);
#endif
#ifdef SYSTEM_CLOBBERS_R13
        // Restore pointer to .sdata section
        set_r13(R13);
#endif

#if ENABLE_VOSF
        // Handle screen fault.
        extern bool Screen_fault_handler(sigsegv_address_t fault_address, sigsegv_address_t fault_instruction);
        if (Screen_fault_handler((sigsegv_address_t)addr, (sigsegv_address_t)r->pc()))
                return;
#endif

        num_segv++;

        // Fault in Mac ROM or RAM or DR Cache?
        bool mac_fault = (r->pc() >= ROM_BASE) && (r->pc() < (ROM_BASE + ROM_AREA_SIZE)) || (r->pc() >= RAMBase) && (r->pc() < (RAMBase + RAMSize)) || (r->pc() >= DR_CACHE_BASE && r->pc() < (DR_CACHE_BASE + DR_CACHE_SIZE));
        if (mac_fault) {

                // "VM settings" during MacOS 8 installation
                if (r->pc() == ROM_BASE + 0x488160 && r->gpr(20) == 0xf8000000) {
                        r->pc() += 4;
                        r->gpr(8) = 0;
                        return;
        
                // MacOS 8.5 installation
                } else if (r->pc() == ROM_BASE + 0x488140 && r->gpr(16) == 0xf8000000) {
                        r->pc() += 4;
                        r->gpr(8) = 0;
                        return;
        
                // MacOS 8 serial drivers on startup
                } else if (r->pc() == ROM_BASE + 0x48e080 && (r->gpr(8) == 0xf3012002 || r->gpr(8) == 0xf3012000)) {
                        r->pc() += 4;
                        r->gpr(8) = 0;
                        return;
        
                // MacOS 8.1 serial drivers on startup
                } else if (r->pc() == ROM_BASE + 0x48c5e0 && (r->gpr(20) == 0xf3012002 || r->gpr(20) == 0xf3012000)) {
                        r->pc() += 4;
                        return;
                } else if (r->pc() == ROM_BASE + 0x4a10a0 && (r->gpr(20) == 0xf3012002 || r->gpr(20) == 0xf3012000)) {
                        r->pc() += 4;
                        return;
        
                // MacOS 8.6 serial drivers on startup (with DR Cache and OldWorld ROM)
                } else if ((r->pc() - DR_CACHE_BASE) < DR_CACHE_SIZE && (r->gpr(16) == 0xf3012002 || r->gpr(16) == 0xf3012000)) {
                        r->pc() += 4;
                        return;
                } else if ((r->pc() - DR_CACHE_BASE) < DR_CACHE_SIZE && (r->gpr(20) == 0xf3012002 || r->gpr(20) == 0xf3012000)) {
                        r->pc() += 4;
                        return;
                }

                // Get opcode and divide into fields
                uint32 opcode = *((uint32 *)r->pc());
                uint32 primop = opcode >> 26;
                uint32 exop = (opcode >> 1) & 0x3ff;
                uint32 ra = (opcode >> 16) & 0x1f;
                uint32 rb = (opcode >> 11) & 0x1f;
                uint32 rd = (opcode >> 21) & 0x1f;
                int32 imm = (int16)(opcode & 0xffff);

                // Analyze opcode
                enum {
                        TYPE_UNKNOWN,
                        TYPE_LOAD,
                        TYPE_STORE
                } transfer_type = TYPE_UNKNOWN;
                enum {
                        SIZE_UNKNOWN,
                        SIZE_BYTE,
                        SIZE_HALFWORD,
                        SIZE_WORD
                } transfer_size = SIZE_UNKNOWN;
                enum {
                        MODE_UNKNOWN,
                        MODE_NORM,
                        MODE_U,
                        MODE_X,
                        MODE_UX
                } addr_mode = MODE_UNKNOWN;
                switch (primop) {
                        case 31:
                                switch (exop) {
                                        case 23:        // lwzx
                                                transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_X; break;
                                        case 55:        // lwzux
                                                transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_UX; break;
                                        case 87:        // lbzx
                                                transfer_type = TYPE_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_X; break;
                                        case 119:       // lbzux
                                                transfer_type = TYPE_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_UX; break;
                                        case 151:       // stwx
                                                transfer_type = TYPE_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_X; break;
                                        case 183:       // stwux
                                                transfer_type = TYPE_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_UX; break;
                                        case 215:       // stbx
                                                transfer_type = TYPE_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_X; break;
                                        case 247:       // stbux
                                                transfer_type = TYPE_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_UX; break;
                                        case 279:       // lhzx
                                                transfer_type = TYPE_LOAD; transfer_size = SIZE_HALFWORD; addr_mode = MODE_X; break;
                                        case 311:       // lhzux
                                                transfer_type = TYPE_LOAD; transfer_size = SIZE_HALFWORD; addr_mode = MODE_UX; break;
                                        case 343:       // lhax
                                                transfer_type = TYPE_LOAD; transfer_size = SIZE_HALFWORD; addr_mode = MODE_X; break;
                                        case 375:       // lhaux
                                                transfer_type = TYPE_LOAD; transfer_size = SIZE_HALFWORD; addr_mode = MODE_UX; break;
                                        case 407:       // sthx
                                                transfer_type = TYPE_STORE; transfer_size = SIZE_HALFWORD; addr_mode = MODE_X; break;
                                        case 439:       // sthux
                                                transfer_type = TYPE_STORE; transfer_size = SIZE_HALFWORD; addr_mode = MODE_UX; break;
                                }
                                break;
        
                        case 32:        // lwz
                                transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_NORM; break;
                        case 33:        // lwzu
                                transfer_type = TYPE_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_U; break;
                        case 34:        // lbz
                                transfer_type = TYPE_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_NORM; break;
                        case 35:        // lbzu
                                transfer_type = TYPE_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_U; break;
                        case 36:        // stw
                                transfer_type = TYPE_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_NORM; break;
                        case 37:        // stwu
                                transfer_type = TYPE_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_U; break;
                        case 38:        // stb
                                transfer_type = TYPE_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_NORM; break;
                        case 39:        // stbu
                                transfer_type = TYPE_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_U; break;
                        case 40:        // lhz
                                transfer_type = TYPE_LOAD; transfer_size = SIZE_HALFWORD; addr_mode = MODE_NORM; break;
                        case 41:        // lhzu
                                transfer_type = TYPE_LOAD; transfer_size = SIZE_HALFWORD; addr_mode = MODE_U; break;
                        case 42:        // lha
                                transfer_type = TYPE_LOAD; transfer_size = SIZE_HALFWORD; addr_mode = MODE_NORM; break;
                        case 43:        // lhau
                                transfer_type = TYPE_LOAD; transfer_size = SIZE_HALFWORD; addr_mode = MODE_U; break;
                        case 44:        // sth
                                transfer_type = TYPE_STORE; transfer_size = SIZE_HALFWORD; addr_mode = MODE_NORM; break;
                        case 45:        // sthu
                                transfer_type = TYPE_STORE; transfer_size = SIZE_HALFWORD; addr_mode = MODE_U; break;
#if EMULATE_UNALIGNED_LOADSTORE_MULTIPLE
                        case 46:        // lmw
                                if ((addr % 4) != 0) {
                                        uint32 ea = addr;
                                        D(bug("WARNING: unaligned lmw to EA=%08x from IP=%08x\n", ea, r->pc()));
                                        for (int i = rd; i <= 31; i++) {
                                                r->gpr(i) = ReadMacInt32(ea);
                                                ea += 4;
                                        }
                                        r->pc() += 4;
                                        goto rti;
                                }
                                break;
                        case 47:        // stmw
                                if ((addr % 4) != 0) {
                                        uint32 ea = addr;
                                        D(bug("WARNING: unaligned stmw to EA=%08x from IP=%08x\n", ea, r->pc()));
                                        for (int i = rd; i <= 31; i++) {
                                                WriteMacInt32(ea, r->gpr(i));
                                                ea += 4;
                                        }
                                        r->pc() += 4;
                                        goto rti;
                                }
                                break;
#endif
                }
        
                // Ignore ROM writes (including to the zero page, which is read-only)
                if (transfer_type == TYPE_STORE &&
                        ((addr >= ROM_BASE && addr < ROM_BASE + ROM_SIZE) ||
                         (addr >= SheepMem::ZeroPage() && addr < SheepMem::ZeroPage() + SheepMem::PageSize()))) {
//                      D(bug("WARNING: %s write access to ROM at %08lx, pc %08lx\n", transfer_size == SIZE_BYTE ? "Byte" : transfer_size == SIZE_HALFWORD ? "Halfword" : "Word", addr, r->pc()));
                        if (addr_mode == MODE_U || addr_mode == MODE_UX)
                                r->gpr(ra) = addr;
                        r->pc() += 4;
                        goto rti;
                }

                // Ignore illegal memory accesses?
                if (PrefsFindBool("ignoresegv")) {
                        if (addr_mode == MODE_U || addr_mode == MODE_UX)
                                r->gpr(ra) = addr;
                        if (transfer_type == TYPE_LOAD)
                                r->gpr(rd) = 0;
                        r->pc() += 4;
                        goto rti;
                }

                // In GUI mode, show error alert
                if (!PrefsFindBool("nogui")) {
                        char str[256];
                        if (transfer_type == TYPE_LOAD || transfer_type == TYPE_STORE)
                                sprintf(str, GetString(STR_MEM_ACCESS_ERR), transfer_size == SIZE_BYTE ? "byte" : transfer_size == SIZE_HALFWORD ? "halfword" : "word", transfer_type == TYPE_LOAD ? GetString(STR_MEM_ACCESS_READ) : GetString(STR_MEM_ACCESS_WRITE), addr, r->pc(), r->gpr(24), r->gpr(1));
                        else
                                sprintf(str, GetString(STR_UNKNOWN_SEGV_ERR), r->pc(), r->gpr(24), r->gpr(1), opcode);
                        ErrorAlert(str);
                        QuitEmulator();
                        return;
                }
        }

        // For all other errors, jump into debugger (sort of...)
        crash_reason = (sig == SIGBUS) ? "SIGBUS" : "SIGSEGV";
        if (!ready_for_signals) {
                printf("%s\n");
                printf(" sigcontext %p, machine_regs %p\n", scp, r);
                printf(
                        "   pc %08lx     lr %08lx    ctr %08lx    msr %08lx\n"
                        "  xer %08lx     cr %08lx  \n"
                        "   r0 %08lx     r1 %08lx     r2 %08lx     r3 %08lx\n"
                        "   r4 %08lx     r5 %08lx     r6 %08lx     r7 %08lx\n"
                        "   r8 %08lx     r9 %08lx    r10 %08lx    r11 %08lx\n"
                        "  r12 %08lx    r13 %08lx    r14 %08lx    r15 %08lx\n"
                        "  r16 %08lx    r17 %08lx    r18 %08lx    r19 %08lx\n"
                        "  r20 %08lx    r21 %08lx    r22 %08lx    r23 %08lx\n"
                        "  r24 %08lx    r25 %08lx    r26 %08lx    r27 %08lx\n"
                        "  r28 %08lx    r29 %08lx    r30 %08lx    r31 %08lx\n",
                        crash_reason,
                        r->pc(), r->lr(), r->ctr(), r->msr(),
                        r->xer(), r->cr(),
                        r->gpr(0), r->gpr(1), r->gpr(2), r->gpr(3),
                        r->gpr(4), r->gpr(5), r->gpr(6), r->gpr(7),
                        r->gpr(8), r->gpr(9), r->gpr(10), r->gpr(11),
                        r->gpr(12), r->gpr(13), r->gpr(14), r->gpr(15),
                        r->gpr(16), r->gpr(17), r->gpr(18), r->gpr(19),
                        r->gpr(20), r->gpr(21), r->gpr(22), r->gpr(23),
                        r->gpr(24), r->gpr(25), r->gpr(26), r->gpr(27),
                        r->gpr(28), r->gpr(29), r->gpr(30), r->gpr(31));
                exit(1);
                QuitEmulator();
                return;
        } else {
                // We crashed. Save registers, tell tick thread and loop forever
                build_sigregs(&sigsegv_regs, r);
                emul_thread_fatal = true;
                for (;;) ;
        }
rti:;
}


/*
 *  SIGILL handler
 */

static void sigill_handler(int sig, siginfo_t *sip, void *scp)
{
        machine_regs *r = MACHINE_REGISTERS(scp);
        char str[256];

#ifdef SYSTEM_CLOBBERS_R2
        // Restore pointer to Thread Local Storage
        set_r2(TOC);
#endif
#ifdef SYSTEM_CLOBBERS_R13
        // Restore pointer to .sdata section
        set_r13(R13);
#endif

        // Fault in Mac ROM or RAM?
        bool mac_fault = (r->pc() >= ROM_BASE) && (r->pc() < (ROM_BASE + ROM_AREA_SIZE)) || (r->pc() >= RAMBase) && (r->pc() < (RAMBase + RAMSize));
        if (mac_fault) {

                // Get opcode and divide into fields
                uint32 opcode = *((uint32 *)r->pc());
                uint32 primop = opcode >> 26;
                uint32 exop = (opcode >> 1) & 0x3ff;
                uint32 ra = (opcode >> 16) & 0x1f;
                uint32 rb = (opcode >> 11) & 0x1f;
                uint32 rd = (opcode >> 21) & 0x1f;
                int32 imm = (int16)(opcode & 0xffff);

                switch (primop) {
                        case 9:         // POWER instructions
                        case 22:
power_inst:             sprintf(str, GetString(STR_POWER_INSTRUCTION_ERR), r->pc(), r->gpr(1), opcode);
                                ErrorAlert(str);
                                QuitEmulator();
                                return;

                        case 31:
                                switch (exop) {
                                        case 83:        // mfmsr
                                                r->gpr(rd) = 0xf072;
                                                r->pc() += 4;
                                                goto rti;

                                        case 210:       // mtsr
                                        case 242:       // mtsrin
                                        case 306:       // tlbie
                                                r->pc() += 4;
                                                goto rti;

                                        case 339: {     // mfspr
                                                int spr = ra | (rb << 5);
                                                switch (spr) {
                                                        case 0:         // MQ
                                                        case 22:        // DEC
                                                        case 952:       // MMCR0
                                                        case 953:       // PMC1
                                                        case 954:       // PMC2
                                                        case 955:       // SIA
                                                        case 956:       // MMCR1
                                                        case 957:       // PMC3
                                                        case 958:       // PMC4
                                                        case 959:       // SDA
                                                                r->pc() += 4;
                                                                goto rti;
                                                        case 25:        // SDR1
                                                                r->gpr(rd) = 0xdead001f;
                                                                r->pc() += 4;
                                                                goto rti;
                                                        case 287:       // PVR
                                                                r->gpr(rd) = PVR;
                                                                r->pc() += 4;
                                                                goto rti;
                                                }
                                                break;
                                        }

                                        case 467: {     // mtspr
                                                int spr = ra | (rb << 5);
                                                switch (spr) {
                                                        case 0:         // MQ
                                                        case 22:        // DEC
                                                        case 275:       // SPRG3
                                                        case 528:       // IBAT0U
                                                        case 529:       // IBAT0L
                                                        case 530:       // IBAT1U
                                                        case 531:       // IBAT1L
                                                        case 532:       // IBAT2U
                                                        case 533:       // IBAT2L
                                                        case 534:       // IBAT3U
                                                        case 535:       // IBAT3L
                                                        case 536:       // DBAT0U
                                                        case 537:       // DBAT0L
                                                        case 538:       // DBAT1U
                                                        case 539:       // DBAT1L
                                                        case 540:       // DBAT2U
                                                        case 541:       // DBAT2L
                                                        case 542:       // DBAT3U
                                                        case 543:       // DBAT3L
                                                        case 952:       // MMCR0
                                                        case 953:       // PMC1
                                                        case 954:       // PMC2
                                                        case 955:       // SIA
                                                        case 956:       // MMCR1
                                                        case 957:       // PMC3
                                                        case 958:       // PMC4
                                                        case 959:       // SDA
                                                                r->pc() += 4;
                                                                goto rti;
                                                }
                                                break;
                                        }

                                        case 29: case 107: case 152: case 153:  // POWER instructions
                                        case 184: case 216: case 217: case 248:
                                        case 264: case 277: case 331: case 360:
                                        case 363: case 488: case 531: case 537:
                                        case 541: case 664: case 665: case 696:
                                        case 728: case 729: case 760: case 920:
                                        case 921: case 952:
                                                goto power_inst;
                                }
                }

                // In GUI mode, show error alert
                if (!PrefsFindBool("nogui")) {
                        sprintf(str, GetString(STR_UNKNOWN_SEGV_ERR), r->pc(), r->gpr(24), r->gpr(1), opcode);
                        ErrorAlert(str);
                        QuitEmulator();
                        return;
                }
        }

        // For all other errors, jump into debugger (sort of...)
        crash_reason = "SIGILL";
        if (!ready_for_signals) {
                printf("%s\n");
                printf(" sigcontext %p, machine_regs %p\n", scp, r);
                printf(
                        "   pc %08lx     lr %08lx    ctr %08lx    msr %08lx\n"
                        "  xer %08lx     cr %08lx  \n"
                        "   r0 %08lx     r1 %08lx     r2 %08lx     r3 %08lx\n"
                        "   r4 %08lx     r5 %08lx     r6 %08lx     r7 %08lx\n"
                        "   r8 %08lx     r9 %08lx    r10 %08lx    r11 %08lx\n"
                        "  r12 %08lx    r13 %08lx    r14 %08lx    r15 %08lx\n"
                        "  r16 %08lx    r17 %08lx    r18 %08lx    r19 %08lx\n"
                        "  r20 %08lx    r21 %08lx    r22 %08lx    r23 %08lx\n"
                        "  r24 %08lx    r25 %08lx    r26 %08lx    r27 %08lx\n"
                        "  r28 %08lx    r29 %08lx    r30 %08lx    r31 %08lx\n",
                        crash_reason,
                        r->pc(), r->lr(), r->ctr(), r->msr(),
                        r->xer(), r->cr(),
                        r->gpr(0), r->gpr(1), r->gpr(2), r->gpr(3),
                        r->gpr(4), r->gpr(5), r->gpr(6), r->gpr(7),
                        r->gpr(8), r->gpr(9), r->gpr(10), r->gpr(11),
                        r->gpr(12), r->gpr(13), r->gpr(14), r->gpr(15),
                        r->gpr(16), r->gpr(17), r->gpr(18), r->gpr(19),
                        r->gpr(20), r->gpr(21), r->gpr(22), r->gpr(23),
                        r->gpr(24), r->gpr(25), r->gpr(26), r->gpr(27),
                        r->gpr(28), r->gpr(29), r->gpr(30), r->gpr(31));
                exit(1);
                QuitEmulator();
                return;
        } else {
                // We crashed. Save registers, tell tick thread and loop forever
                build_sigregs(&sigsegv_regs, r);
                emul_thread_fatal = true;
                for (;;) ;
        }
rti:;
}
#endif


/*
 *  Helpers to share 32-bit addressable data with MacOS
 */

bool SheepMem::Init(void)
{
        // Size of a native page
        page_size = getpagesize();

        // Allocate SheepShaver globals
        proc = base;
        if (vm_mac_acquire(base, size) < 0)
                return false;

        // Allocate page with all bits set to 0, right in the middle
        // This is also used to catch undesired overlaps between proc and data areas
        zero_page = proc + (size / 2);
        Mac_memset(zero_page, 0, page_size);
        if (vm_protect(Mac2HostAddr(zero_page), page_size, VM_PAGE_READ) < 0)
                return false;

#if EMULATED_PPC
        // Allocate alternate stack for PowerPC interrupt routine
        sig_stack = base + size;
        if (vm_mac_acquire(sig_stack, SIG_STACK_SIZE) < 0)
                return false;
#endif

        data = base + size;
        return true;
}

void SheepMem::Exit(void)
{
        if (data) {
                // Delete SheepShaver globals
                vm_mac_release(base, size);

#if EMULATED_PPC
                // Delete alternate stack for PowerPC interrupt routine
                vm_mac_release(sig_stack, SIG_STACK_SIZE);
#endif
        }
}


/*
 *  Display alert
 */

#ifdef ENABLE_GTK
static void dl_destroyed(void)
{
        gtk_main_quit();
}

static void dl_quit(GtkWidget *dialog)
{
        gtk_widget_destroy(dialog);
}

void display_alert(int title_id, int prefix_id, int button_id, const char *text)
{
        char str[256];
        sprintf(str, GetString(prefix_id), text);

        GtkWidget *dialog = gtk_dialog_new();
        gtk_window_set_title(GTK_WINDOW(dialog), GetString(title_id));
        gtk_container_border_width(GTK_CONTAINER(dialog), 5);
        gtk_widget_set_uposition(GTK_WIDGET(dialog), 100, 150);
        gtk_signal_connect(GTK_OBJECT(dialog), "destroy", GTK_SIGNAL_FUNC(dl_destroyed), NULL);

        GtkWidget *label = gtk_label_new(str);
        gtk_widget_show(label);
        gtk_box_pack_start(GTK_BOX(GTK_DIALOG(dialog)->vbox), label, TRUE, TRUE, 0);

        GtkWidget *button = gtk_button_new_with_label(GetString(button_id));
        gtk_widget_show(button);
        gtk_signal_connect_object(GTK_OBJECT(button), "clicked", GTK_SIGNAL_FUNC(dl_quit), GTK_OBJECT(dialog));
        gtk_box_pack_start(GTK_BOX(GTK_DIALOG(dialog)->action_area), button, FALSE, FALSE, 0);
        GTK_WIDGET_SET_FLAGS(button, GTK_CAN_DEFAULT);
        gtk_widget_grab_default(button);
        gtk_widget_show(dialog);

        gtk_main();
}
#endif


/*
 *  Display error alert
 */

void ErrorAlert(const char *text)
{
#if defined(ENABLE_GTK) && !defined(USE_SDL_VIDEO)
        if (PrefsFindBool("nogui") || x_display == NULL) {
                printf(GetString(STR_SHELL_ERROR_PREFIX), text);
                return;
        }
        VideoQuitFullScreen();
        display_alert(STR_ERROR_ALERT_TITLE, STR_GUI_ERROR_PREFIX, STR_QUIT_BUTTON, text);
#else
        printf(GetString(STR_SHELL_ERROR_PREFIX), text);
#endif
}


/*
 *  Display warning alert
 */

void WarningAlert(const char *text)
{
#if defined(ENABLE_GTK) && !defined(USE_SDL_VIDEO)
        if (PrefsFindBool("nogui") || x_display == NULL) {
                printf(GetString(STR_SHELL_WARNING_PREFIX), text);
                return;
        }
        display_alert(STR_WARNING_ALERT_TITLE, STR_GUI_WARNING_PREFIX, STR_OK_BUTTON, text);
#else
        printf(GetString(STR_SHELL_WARNING_PREFIX), text);
#endif
}


/*
 *  Display choice alert
 */

bool ChoiceAlert(const char *text, const char *pos, const char *neg)
{
        printf(GetString(STR_SHELL_WARNING_PREFIX), text);
        return false;   //!!
}
Revision:	1.65
Committed:	2005-06-28T16:47:32Z (19 years, 4 months ago) by gbeauche
Branch:	MAIN
Changes since 1.64:	+39 -61 lines
Log Message:	The alternate stack trick never worked as you can't modify an active stack. i.e. it returned EPERM and ran into stack corruption to eventually crash the emulator. This is noticeable in !hw_mac_cursor_accl mode (e.g. fullscreen DGA). In order to the sigalstack() to be effective, we must kludge the kernel to think it's running on another stack. In practise, we provide another stack for the SIGUSR2 handler. sigusr2_handler_init() fulfills that purpose. I hope this fixes remaining issues forever. At some point, I had multiple *_init() handlers in case this is necessary.