src/BeOS/main_beos.cpp

/*
 *  main_beos.cpp - Startup code for BeOS
 *
 *  Basilisk II (C) 1997-1999 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
 *  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
 */

#include <AppKit.h>
#include <InterfaceKit.h>
#include <KernelKit.h>
#include <StorageKit.h>

#include <unistd.h>
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>

#include "sysdeps.h"
#include "cpu_emulation.h"
#include "xpram.h"
#include "timer.h"
#include "sony.h"
#include "disk.h"
#include "cdrom.h"
#include "scsi.h"
#include "audio.h"
#include "video.h"
#include "serial.h"
#include "ether.h"
#include "clip.h"
#include "rom_patches.h"
#include "prefs.h"
#include "prefs_editor.h"
#include "sys.h"
#include "user_strings.h"
#include "version.h"
#include "main.h"

#include "sheep_driver.h"

#define DEBUG 0
#include "debug.h"


// Constants
const char APP_SIGNATURE[] = "application/x-vnd.cebix-BasiliskII";
const char ROM_FILE_NAME[] = "ROM";
const char RAM_AREA_NAME[] = "Macintosh RAM";
const char ROM_AREA_NAME[] = "Macintosh ROM";
const uint32 MSG_START = 'strt';                        // Emulator start message
const uint32 ROM_AREA_SIZE = 0x500000;          // Enough to hold PowerMac ROM (for powerrom_cpu)

// Prototypes
#if __POWERPC__
static void sigsegv_handler(vregs *r);
#endif


// Application object
class BasiliskII : public BApplication {
public:
        BasiliskII() : BApplication(APP_SIGNATURE)
        {
                // Find application directory and cwd to it
                app_info the_info;
                GetAppInfo(&the_info);
                BEntry the_file(&the_info.ref);
                BEntry the_dir;
                the_file.GetParent(&the_dir);
                BPath the_path;
                the_dir.GetPath(&the_path);
                chdir(the_path.Path());

                // Initialize other variables
                rom_area = ram_area = -1;
                xpram_thread = tick_thread = -1;
                xpram_thread_active = true;
                tick_thread_active = true;
                AllowQuitting = true;
        }
        virtual void ReadyToRun(void);
        virtual void MessageReceived(BMessage *msg);
        void StartEmulator(void);
        virtual bool QuitRequested(void);
        virtual void Quit(void);

        thread_id xpram_thread;         // XPRAM watchdog
        thread_id tick_thread;          // 60Hz thread

        volatile bool xpram_thread_active;      // Flag for quitting the XPRAM thread
        volatile bool tick_thread_active;       // Flag for quitting the 60Hz thread

        bool AllowQuitting;                     // Flag: Alt-Q quitting allowed

private:
        static status_t emul_func(void *arg);
        static status_t tick_func(void *arg);
        static status_t xpram_func(void *arg);
        static void sigsegv_invoc(int sig, void *arg, vregs *r);

        void init_rom(void);
        void load_rom(void);

        area_id rom_area;               // ROM area ID
        area_id ram_area;               // RAM area ID

        struct sigaction sigsegv_action;        // Data access exception signal (of emulator thread)

        // Exceptions
        class area_error {};
        class file_open_error {};
        class file_read_error {};
        class rom_size_error {};
};

static BasiliskII *the_app;


// CPU and FPU type, addressing mode
int CPUType;
bool CPUIs68060;
int FPUType;
bool TwentyFourBitAddressing;


// Global variables for PowerROM CPU
thread_id emul_thread = -1;                     // Emulator thread

#if __POWERPC__
int sheep_fd = -1;                                      // fd of sheep driver
#endif


/*
 *  Create application object and start it
 */

int main(int argc, char **argv)
{       
        the_app = new BasiliskII();
        the_app->Run();
        delete the_app;
        return 0;
}


/*
 *  Run application
 */

void BasiliskII::ReadyToRun(void)
{
        // Initialize variables
        RAMBaseHost = NULL;
        ROMBaseHost = NULL;
        srand(real_time_clock());
        tzset();

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

        // Delete old areas
        area_id old_ram_area = find_area(RAM_AREA_NAME);
        if (old_ram_area > 0)
                delete_area(old_ram_area);
        area_id old_rom_area = find_area(ROM_AREA_NAME);
        if (old_rom_area > 0)
                delete_area(old_rom_area);

        // Read preferences
        PrefsInit();

        // Init system routines
        SysInit();

        // Show preferences editor (or start emulator directly)
        if (!PrefsFindBool("nogui"))
                PrefsEditor();
        else
                PostMessage(MSG_START);
}


/*
 *  Message received
 */

void BasiliskII::MessageReceived(BMessage *msg)
{
        switch (msg->what) {
                case MSG_START:
                        StartEmulator();
                        break;
                default:
                        BApplication::MessageReceived(msg);
        }
}


/*
 *  Start emulator
 */

void BasiliskII::StartEmulator(void)
{
        char str[256];

#if REAL_ADDRESSING
        // Open memory mess driver and remap low memory
        sheep_fd = open("/dev/sheep", 0);
        if (sheep_fd < 0) {
                sprintf(str, GetString(STR_NO_SHEEP_DRIVER_ERR), strerror(sheep_fd), sheep_fd);
                ErrorAlert(str);
                PostMessage(B_QUIT_REQUESTED);
                return;
        }
        status_t res = ioctl(sheep_fd, SHEEP_UP);
        if (res < 0) {
                sprintf(str, GetString(STR_SHEEP_UP_ERR), strerror(res), res);
                ErrorAlert(str);
                PostMessage(B_QUIT_REQUESTED);
                return;
        }
#endif

        // Create area for Mac RAM
        RAMSize = PrefsFindInt32("ramsize") & 0xfff00000;       // Round down to 1MB boundary
        if (RAMSize < 1024*1024) {
                WarningAlert(GetString(STR_SMALL_RAM_WARN));
                RAMSize = 1024*1024;
        }

        RAMBaseHost = (uint8 *)0x10000000;
        ram_area = create_area(RAM_AREA_NAME, (void **)&RAMBaseHost, B_BASE_ADDRESS, RAMSize, B_NO_LOCK, B_READ_AREA | B_WRITE_AREA);
        if (ram_area < 0) {
                ErrorAlert(GetString(STR_NO_RAM_AREA_ERR));
                PostMessage(B_QUIT_REQUESTED);
                return;
        }
        D(bug("RAM area %ld at %p\n", ram_area, RAMBaseHost));

        // Create area and load Mac ROM
        try {
                init_rom();
        } catch (area_error) {
                ErrorAlert(GetString(STR_NO_ROM_AREA_ERR));
                PostMessage(B_QUIT_REQUESTED);
                return;
        } catch (file_open_error) {
                ErrorAlert(GetString(STR_NO_ROM_FILE_ERR));
                PostMessage(B_QUIT_REQUESTED);
                return;
        } catch (file_read_error) {
                ErrorAlert(GetString(STR_ROM_FILE_READ_ERR));
                PostMessage(B_QUIT_REQUESTED);
                return;
        } catch (rom_size_error) {
                ErrorAlert(GetString(STR_ROM_SIZE_ERR));
                PostMessage(B_QUIT_REQUESTED);
                return;
        }

        // Check ROM version
        if (!CheckROM()) {
                ErrorAlert(GetString(STR_UNSUPPORTED_ROM_TYPE_ERR));
                PostMessage(B_QUIT_REQUESTED);
                return;
        }

        // Set CPU and FPU type (UAE emulation)
        switch (ROMVersion) {
                case ROM_VERSION_64K:
                case ROM_VERSION_PLUS:
                case ROM_VERSION_CLASSIC:
                        CPUType = 0;
                        FPUType = 0;
                        TwentyFourBitAddressing = true;
                        break;
                case ROM_VERSION_II:
                        CPUType = 2;
                        FPUType = PrefsFindBool("fpu") ? 1 : 0;
                        TwentyFourBitAddressing = true;
                        break;
                case ROM_VERSION_32:
                        CPUType = 3;
                        FPUType = PrefsFindBool("fpu") ? 1 : 0;
                        TwentyFourBitAddressing = false;
                        break;
        }
        CPUIs68060 = false;

        // Load XPRAM
        XPRAMInit();

        // Set boot volume
        int16 i16 = PrefsFindInt16("bootdrive");
        XPRAM[0x78] = i16 >> 8;
        XPRAM[0x79] = i16 & 0xff;
        i16 = PrefsFindInt16("bootdriver");
        XPRAM[0x7a] = i16 >> 8;
        XPRAM[0x7b] = i16 & 0xff;

        // Start XPRAM watchdog thread
        xpram_thread = spawn_thread(xpram_func, "XPRAM Watchdog", B_LOW_PRIORITY, this);
        resume_thread(xpram_thread);

        // Init drivers
        SonyInit();
        DiskInit();
        CDROMInit();
        SCSIInit();

        // Init network
        EtherInit();

        // Init serial ports
        SerialInit();

        // Init Time Manager
        TimerInit();

        // Init clipboard
        ClipInit();

        // Init audio
        AudioInit();

        // Init video
        if (!VideoInit(ROMVersion == ROM_VERSION_64K || ROMVersion == ROM_VERSION_PLUS || ROMVersion == ROM_VERSION_CLASSIC)) {
                PostMessage(B_QUIT_REQUESTED);
                return;
        }

        // Init 680x0 emulation (this also activates the memory system which is needed for PatchROM())
        if (!Init680x0()) {
                PostMessage(B_QUIT_REQUESTED);
                return;
        }

        // Install ROM patches
        if (!PatchROM()) {
                ErrorAlert(GetString(STR_UNSUPPORTED_ROM_TYPE_ERR));
                PostMessage(B_QUIT_REQUESTED);
                return;
        }

        // Write protect ROM
        set_area_protection(rom_area, B_READ_AREA);

        // Disallow quitting with Alt-Q from now on
        AllowQuitting = false;

        // Start 60Hz interrupt
        tick_thread = spawn_thread(tick_func, "60Hz", B_REAL_TIME_PRIORITY, this);
        resume_thread(tick_thread);

        // Start emulator thread
        emul_thread = spawn_thread(emul_func, "MacOS", B_NORMAL_PRIORITY, this);
        resume_thread(emul_thread);
}


/*
 *  Quit emulator
 */

void QuitEmulator(void)
{
        the_app->AllowQuitting = true;
        be_app->PostMessage(B_QUIT_REQUESTED);
        exit_thread(0);
}

bool BasiliskII::QuitRequested(void)
{
        if (AllowQuitting)
                return BApplication::QuitRequested();
        else
                return false;
}

void BasiliskII::Quit(void)
{
        status_t l;

        // Stop 60Hz interrupt
        if (tick_thread > 0) {
                tick_thread_active = false;
                wait_for_thread(tick_thread, &l);
        }

        // Wait for emulator thread to finish
        if (emul_thread > 0)
                wait_for_thread(emul_thread, &l);

        // Exit 680x0 emulation
        Exit680x0();

        // Stop XPRAM watchdog thread
        if (xpram_thread > 0) {
                xpram_thread_active = false;
                suspend_thread(xpram_thread);   // Wake thread up from snooze()
                snooze(1000);
                resume_thread(xpram_thread);
                wait_for_thread(xpram_thread, &l);
        }

        // Save XPRAM
        XPRAMExit();

        // Exit video
        VideoExit();

        // Exit audio
        AudioExit();

        // Exit clipboard
        ClipExit();

        // Exit Time Manager
        TimerExit();

        // Exit serial ports
        SerialExit();

        // Exit network
        EtherExit();

        // Exit drivers
        SCSIExit();
        CDROMExit();
        DiskExit();
        SonyExit();

        // Delete ROM area
        if (rom_area >= 0)
                delete_area(rom_area);

        // Delete RAM area
        if (ram_area >= 0)
                delete_area(ram_area);

#if REAL_ADDRESSING
        // Unmap low memory and close memory mess driver
        if (sheep_fd >= 0) {
                ioctl(sheep_fd, SHEEP_DOWN);
                close(sheep_fd);
        }
#endif

        // Exit system routines
        SysExit();

        // Exit preferences
        PrefsExit();

        BApplication::Quit();
}


/*
 *  Create area for ROM (sets rom_area) and load ROM file
 *
 *  area_error     : Cannot create area
 *  file_open_error: Cannot open ROM file
 *  file_read_error: Cannot read ROM file
 */

void BasiliskII::init_rom(void)
{
        // Create area for ROM
        ROMBaseHost = (uint8 *)0x40800000;
        rom_area = create_area(ROM_AREA_NAME, (void **)&ROMBaseHost, B_BASE_ADDRESS, ROM_AREA_SIZE, B_NO_LOCK, B_READ_AREA | B_WRITE_AREA);
        if (rom_area < 0)
                throw area_error();
        D(bug("ROM area %ld at %p\n", rom_area, ROMBaseHost));

        // Load ROM
        load_rom();
}


/*
 *  Load ROM file
 *
 *  file_open_error: Cannot open ROM file
 *  file_read_error: Cannot read ROM file
 */

void BasiliskII::load_rom(void)
{
        // Get rom file path from preferences
        const char *rom_path = PrefsFindString("rom");

        // Try to open ROM file
        BFile file(rom_path ? rom_path : ROM_FILE_NAME, B_READ_ONLY);
        if (file.InitCheck() != B_NO_ERROR)
                throw file_open_error();

        printf(GetString(STR_READING_ROM_FILE));

        // Is the ROM size correct?
        off_t rom_size = 0;
        file.GetSize(&rom_size);
        if (rom_size != 64*1024 && rom_size != 128*1024 && rom_size != 256*1024 && rom_size != 512*1024 && rom_size != 1024*1024)
                throw rom_size_error();

        uint8 *rom = new uint8[rom_size];       // Reading directly into the area doesn't work
        ssize_t actual = file.Read((void *)rom, rom_size);
        if (actual == rom_size)
                memcpy(ROMBaseHost, rom, rom_size);
        delete[] rom;
        if (actual != rom_size)
                throw file_read_error();
        ROMSize = rom_size;
}


/*
 *  Emulator thread function
 */

status_t BasiliskII::emul_func(void *arg)
{
        BasiliskII *obj = (BasiliskII *)arg;

#if __POWERPC__
        // Install data access signal handler
        sigemptyset(&obj->sigsegv_action.sa_mask);
        obj->sigsegv_action.sa_handler = (__signal_func_ptr)(obj->sigsegv_invoc);
        obj->sigsegv_action.sa_flags = 0;
        obj->sigsegv_action.sa_userdata = arg;
        sigaction(SIGSEGV, &obj->sigsegv_action, NULL);
#endif

        // Exceptions will send signals
        disable_debugger(true);

        // Start 68k and jump to ROM boot routine
        Start680x0();

        // Quit program
        obj->AllowQuitting = true;
        be_app->PostMessage(B_QUIT_REQUESTED);
        return 0;
}


/*
 *  Code was patched, flush caches if neccessary (i.e. when using a real 680x0
 *  or a dynamically recompiling emulator)
 */

void FlushCodeCache(void *start, uint32 size)
{
}


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

uint32 InterruptFlags = 0;

void SetInterruptFlag(uint32 flag)
{
        atomic_or((int32 *)&InterruptFlags, flag);
}

void ClearInterruptFlag(uint32 flag)
{
        atomic_and((int32 *)&InterruptFlags, ~flag);
}


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

status_t BasiliskII::tick_func(void *arg)
{
        BasiliskII *obj = (BasiliskII *)arg;
        int tick_counter = 0;
        bigtime_t current = system_time();

        while (obj->tick_thread_active) {

                // Wait
                current += 16625;
                snooze_until(current, B_SYSTEM_TIMEBASE);

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

                // Trigger 60Hz interrupt
                SetInterruptFlag(INTFLAG_60HZ);
                TriggerInterrupt();
        }
        return 0;
}


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

status_t BasiliskII::xpram_func(void *arg)
{
        uint8 last_xpram[256];
        memcpy(last_xpram, XPRAM, 256);

        while (((BasiliskII *)arg)->xpram_thread_active) {
                snooze(60*1000000);
                if (memcmp(last_xpram, XPRAM, 256)) {
                        memcpy(last_xpram, XPRAM, 256);
                        SaveXPRAM();
                }
        }
        return 0;
}


/*
 *  Display error alert
 */

void ErrorAlert(const char *text)
{
        if (PrefsFindBool("nogui")) {
                printf(GetString(STR_SHELL_ERROR_PREFIX), text);
                return;
        }
        VideoQuitFullScreen();
        char str[256];
        sprintf(str, GetString(STR_GUI_ERROR_PREFIX), text);
        BAlert *alert = new BAlert(GetString(STR_ERROR_ALERT_TITLE), str, GetString(STR_QUIT_BUTTON), NULL, NULL, B_WIDTH_AS_USUAL, B_STOP_ALERT);
        alert->Go();
}


/*
 *  Display warning alert
 */

void WarningAlert(const char *text)
{
        if (PrefsFindBool("nogui")) {
                printf(GetString(STR_SHELL_WARNING_PREFIX), text);
                return;
        }
        char str[256];
        sprintf(str, GetString(STR_GUI_WARNING_PREFIX), text);
        BAlert *alert = new BAlert(GetString(STR_WARNING_ALERT_TITLE), str, GetString(STR_OK_BUTTON), NULL, NULL, B_WIDTH_AS_USUAL, B_INFO_ALERT);
        alert->Go();
}


/*
 *  Display choice alert
 */

bool ChoiceAlert(const char *text, const char *pos, const char *neg)
{
        char str[256];
        sprintf(str, GetString(STR_GUI_WARNING_PREFIX), text);
        BAlert *alert = new BAlert(GetString(STR_WARNING_ALERT_TITLE), str, pos, neg, NULL, B_WIDTH_AS_USUAL, B_INFO_ALERT);
        return alert->Go() == 0;
}


/*
 *  SEGV handler
 */

#if __POWERPC__
static uint32 segv_r[32];

asm void BasiliskII::sigsegv_invoc(register int sig, register void *arg, register vregs *r)
{
        mflr    r0
        stw             r0,8(r1)
        stwu    r1,-56(r1)

        lwz             r3,segv_r(r2)
        stmw    r13,13*4(r3)

        mr              r3,r5
        bl              sigsegv_handler

        lwz             r3,segv_r(r2)
        lmw             r13,13*4(r3)

        lwz             r0,56+8(r1)
        mtlr    r0
        addi    r1,r1,56
        blr
}

static void sigsegv_handler(vregs *r)
{
        // Fetch volatile registers
        segv_r[0] = r->r0;
        segv_r[1] = r->r1;
        segv_r[2] = r->r2;
        segv_r[3] = r->r3;
        segv_r[4] = r->r4;
        segv_r[5] = r->r5;
        segv_r[6] = r->r6;
        segv_r[7] = r->r7;
        segv_r[8] = r->r8;
        segv_r[9] = r->r9;
        segv_r[10] = r->r10;
        segv_r[11] = r->r11;
        segv_r[12] = r->r12;

        // 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;
        uint32 imm = 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;
        }

        // Calculate effective address
        uint32 addr = 0;
        switch (addr_mode) {
                case MODE_X:
                case MODE_UX:
                        if (ra == 0)
                                addr = segv_r[rb];
                        else
                                addr = segv_r[ra] + segv_r[rb];
                        break;
                case MODE_NORM:
                case MODE_U:
                        if (ra == 0)
                                addr = (int32)(int16)imm;
                        else
                                addr = segv_r[ra] + (int32)(int16)imm;
                        break;
        }

        // Ignore ROM writes
        if (transfer_type == TYPE_STORE && addr >= (uint32)ROMBaseHost && addr < (uint32)ROMBaseHost + ROMSize) {
//              D(bug("WARNING: %s write access to ROM at %p, 68k pc %p\n", transfer_size == SIZE_BYTE ? "Byte" : transfer_size == SIZE_HALFWORD ? "Halfword" : "Word", addr, r->pc));
                if (addr_mode == MODE_U || addr_mode == MODE_UX)
                        segv_r[ra] = addr;
                r->pc += 4;
                goto rti;
        }

        // For all other errors, jump into debugger
        char str[256];
        sprintf(str, "SIGSEGV\n"
                "   pc %08lx     lr %08lx    ctr %08lx    msr %08lx\n"
                "  xer %08lx     cr %08lx  fpscr %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",
                r->pc, r->lr, r->ctr, r->msr,
                r->xer, r->cr, r->fpscr,
                r->r0, r->r1, r->r2, r->r3,
                r->r4, r->r5, r->r6, r->r7,
                r->r8, r->r9, r->r10, r->r11,
                r->r12, segv_r[13], segv_r[14], segv_r[15],
                segv_r[16], segv_r[17], segv_r[18], segv_r[19],
                segv_r[20], segv_r[21], segv_r[22], segv_r[23],
                segv_r[24], segv_r[25], segv_r[26], segv_r[27],
                segv_r[28], segv_r[29], segv_r[30], segv_r[31]);
        disable_debugger(false);
        debugger(str);
        QuitEmulator();
        return;

rti:
        // Restore volatile registers
        r->r0 = segv_r[0];
        r->r1 = segv_r[1];
        r->r2 = segv_r[2];
        r->r3 = segv_r[3];
        r->r4 = segv_r[4];
        r->r5 = segv_r[5];
        r->r6 = segv_r[6];
        r->r7 = segv_r[7];
        r->r8 = segv_r[8];
        r->r9 = segv_r[9];
        r->r10 = segv_r[10];
        r->r11 = segv_r[11];
        r->r12 = segv_r[12];
}
#endif
Revision:	1.1
Committed:	1999-10-03T14:16:25Z (25 years, 1 month ago) by cebix
Branch:	MAIN
Branch point for:	cebix
Log Message:	Initial revision