src/Windows/main_windows.cpp

/*
 *  main_windows.cpp - Emulation core, Windows implementation
 *
 *  SheepShaver (C) 1997-2008 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
 */

#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <SDL.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"
#include "util_windows.h"
#include "kernel_windows.h"

#define DEBUG 0
#include "debug.h"

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


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

const uintptr ROM_BASE = 0x40800000;            // Base address of ROM

const uint32 SIG_STACK_SIZE = 0x10000;          // Size of signal stack


// Global variables (exported)
uint32 RAMBase;                 // Base address of Mac RAM
uint32 RAMSize;                 // Size of Mac RAM
uint32 ROMBase;                 // Base address of Mac ROM
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)
DWORD win_os;                   // Windows OS id
DWORD win_os_major;             // Windows OS version major


// Global variables
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 HANDLE nvram_thread = NULL;                      // NVRAM watchdog
static bool tick_thread_active = false;         // Flag: MacOS thread installed
static volatile bool tick_thread_cancel;        // Flag: Cancel 60Hz thread
static HANDLE tick_thread = NULL;                       // 60Hz thread
static HANDLE emul_thread = NULL;                       // MacOS thread
static uintptr sig_stack = 0;                           // Stack for PowerPC interrupt routine

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 DWORD WINAPI nvram_func(void *arg);
static DWORD WINAPI tick_func(void *arg);

static void jump_to_rom(uint32 entry);
extern void emul_ppc(uint32 start);
extern void init_emul_ppc(void);
extern void exit_emul_ppc(void);
sigsegv_return_t sigsegv_handler(sigsegv_info_t *sip);


/*
 *  Return signal stack base
 */

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


/*
 *  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];
        int16 i16;
        HANDLE rom_fh;
        const char *rom_path;
        uint32 rom_size;
        DWORD actual;
        uint8 *rom_tmp;

        // Initialize variables
        RAMBase = 0;

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

        // Read preferences
        PrefsInit(NULL, argc, argv);

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

        // Check we are using a Windows NT kernel >= 4.0
        OSVERSIONINFO osvi;
        ZeroMemory(&osvi, sizeof(OSVERSIONINFO));
        osvi.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
        if (!GetVersionEx(&osvi)) {
                ErrorAlert("Could not determine OS type");
                QuitEmulator();
        }
        win_os = osvi.dwPlatformId;
        win_os_major = osvi.dwMajorVersion;
        if (win_os != VER_PLATFORM_WIN32_NT || win_os_major < 4) {
                ErrorAlert(GetString(STR_NO_WIN32_NT_4));
                QuitEmulator();
        }

        // Check that drivers are installed
        if (!check_drivers())
                QuitEmulator();

        // Load win32 libraries
        KernelInit();

        // FIXME: default to DIB driver
        if (getenv("SDL_VIDEODRIVER") == NULL)
            putenv("SDL_VIDEODRIVER=windib");

        // 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);

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

        // 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;
        }

        // Initialize VM system
        vm_init();

        // Get system info
        PVR = 0x00040000;                       // Default: 604
        CPUClockSpeed = 100000000;      // Default: 100MHz
        BusClockSpeed = 100000000;      // Default: 100MHz
        TimebaseSpeed =  25000000;      // Default:  25MHz
        PVR = 0x000c0000;                       // Default: 7400 (with AltiVec)
        D(bug("PVR: %08x (assumed)\n", PVR));

        // Init system routines
        SysInit();

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

        // 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;
        DRCacheAddr = (uint32)Mac2HostAddr(DR_CACHE_BASE);
        D(bug("DR Cache at %p (%08x)\n", DRCacheAddr, DR_CACHE_BASE));

        // 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;
        }
        ROMBase = ROM_BASE;
        ROMBaseHost = Mac2HostAddr(ROMBase);
        rom_area_mapped = true;
        D(bug("ROM area at %p (%08x)\n", ROMBaseHost, ROMBase));

        // Create area for Mac RAM
        RAMSize = PrefsFindInt32("ramsize");
        if (RAMSize < 8*1024*1024) {
                WarningAlert(GetString(STR_SMALL_RAM_WARN));
                RAMSize = 8*1024*1024;
        }
        RAMBase = 0;
        if (vm_mac_acquire(RAMBase, RAMSize) < 0) {
                sprintf(str, GetString(STR_RAM_MMAP_ERR), strerror(errno));
                ErrorAlert(str);
                goto quit;
        }
        RAMBaseHost = Mac2HostAddr(RAMBase);
        ram_area_mapped = true;
        D(bug("RAM area at %p (%08x)\n", RAMBaseHost, RAMBase));

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

        // Load Mac ROM
        rom_path = PrefsFindString("rom");
        rom_fh = CreateFile(rom_path ? rom_path : ROM_FILE_NAME,
                                                GENERIC_READ, 0, NULL, OPEN_EXISTING,
                                                FILE_ATTRIBUTE_NORMAL, NULL);

        if (rom_fh == INVALID_HANDLE_VALUE) {
                rom_fh = CreateFile(rom_path ? rom_path : ROM_FILE_NAME2,
                                                        GENERIC_READ, 0, NULL, OPEN_EXISTING,
                                                        FILE_ATTRIBUTE_NORMAL, NULL);

                if (rom_fh == INVALID_HANDLE_VALUE) {
                        ErrorAlert(GetString(STR_NO_ROM_FILE_ERR));
                        goto quit;
                }
        }
        printf(GetString(STR_READING_ROM_FILE));
        rom_size = GetFileSize(rom_fh, NULL);
        rom_tmp = new uint8[ROM_SIZE];
        ReadFile(rom_fh, (void *)rom_tmp, ROM_SIZE, &actual, NULL);
        CloseHandle(rom_fh);
        
        // 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 native timers
        timer_init();

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

        // Write protect ROM
        vm_protect(ROMBaseHost, ROM_AREA_SIZE, VM_PAGE_READ);

        // Start 60Hz thread
        tick_thread_cancel = false;
        tick_thread_active = ((tick_thread = create_thread(tick_func)) != NULL);
        SetThreadPriority(tick_thread, THREAD_PRIORITY_ABOVE_NORMAL);
        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 = ((nvram_thread = create_thread(nvram_func, NULL)) != NULL);
        SetThreadPriority(nvram_thread, THREAD_PRIORITY_BELOW_NORMAL);
        D(bug("NVRAM thread installed (%ld)\n", nvram_thread));

        // Get my thread ID and jump to ROM boot routine
        emul_thread = GetCurrentThread();
        D(bug("Jumping to ROM\n"));
        jump_to_rom(ROMBase + 0x310000);
        D(bug("Returned from ROM\n"));

quit:
        Quit();
        return 0;
}


/*
 *  Cleanup and quit
 */

static void Quit(void)
{
        // Exit PowerPC emulation
        exit_emul_ppc();

        // Stop 60Hz thread
        if (tick_thread_active) {
                tick_thread_cancel = true;
                wait_thread(tick_thread);
        }

        // Stop NVRAM watchdog thread
        if (nvram_thread_active) {
                nvram_thread_cancel = true;
                wait_thread(nvram_thread);
        }

        // Deinitialize everything
        ExitAll();

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

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

        // Delete ROM area
        if (rom_area_mapped)
                vm_mac_release(ROMBase, 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();

        // Exit system routines
        SysExit();

        // Exit preferences
        PrefsExit();

        // Release win32 libraries
        KernelExit();

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

        exit(0);
}


/*
 *  Initialize Kernel Data segments
 */

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

static bool kernel_data_init(void)
{
        char str[256];
        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;
        }
        return true;
}


/*
 *  Deallocate Kernel Data segments
 */

static void kernel_data_exit(void)
{
        if (kernel_handle) {
                UnmapViewOfFile(Mac2HostAddr(KERNEL_DATA_BASE & -allocation_granule));
                UnmapViewOfFile(Mac2HostAddr(KERNEL_DATA2_BASE & -allocation_granule));
                CloseHandle(kernel_handle);
        }
}


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

void jump_to_rom(uint32 entry)
{
        init_emul_ppc();
        emul_ppc(entry);
}


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

void QuitEmulator(void)
{
        Quit();
}


/*
 *  Pause/resume emulator
 */

void PauseEmulator(void)
{
        SuspendThread(emul_thread);
}

void ResumeEmulator(void)
{
        ResumeThread(emul_thread);
}


/*
 *  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 >= ROMBase) && (start < (ROMBase + ROM_SIZE)))
                return;
        FlushCodeCache(start, start + length);
}


/*
 *  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 DWORD 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 0;
}


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

static DWORD 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++;

                // 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("%lu ticks in %lu usec = %f ticks/sec\n", (unsigned long)ticks, (unsigned long)(end - start), ticks * 1000000.0 / (end - start)));
        return 0;
}


/*
 *  Mutexes
 */

struct B2_mutex {
        mutex_t m;
};

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

void B2_lock_mutex(B2_mutex *mutex)
{
        mutex->m.lock();
}

void B2_unlock_mutex(B2_mutex *mutex)
{
        mutex->m.unlock();
}

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


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

volatile uint32 InterruptFlags = 0;
static mutex_t intflags_mutex;

void SetInterruptFlag(uint32 flag)
{
        intflags_mutex.lock();
        InterruptFlags |= flag;
        intflags_mutex.unlock();
}

void ClearInterruptFlag(uint32 flag)
{
        intflags_mutex.lock();
        InterruptFlags &= ~flag;
        intflags_mutex.unlock();
}


/*
 *  Disable interrupts
 */

void DisableInterrupt(void)
{
        WriteMacInt32(XLM_IRQ_NEST, int32(ReadMacInt32(XLM_IRQ_NEST)) + 1);
}


/*
 *  Enable interrupts
 */

void EnableInterrupt(void)
{
        WriteMacInt32(XLM_IRQ_NEST, int32(ReadMacInt32(XLM_IRQ_NEST)) - 1);
}


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

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

        // 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;

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

        data = base + size;
        return true;
}

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

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


/*
 *  Get the main window handle
 */

#ifdef USE_SDL_VIDEO
#include <SDL_syswm.h>
HWND GetMainWindowHandle(void)
{
        SDL_SysWMinfo wmInfo;
        SDL_VERSION(&wmInfo.version);
        return SDL_GetWMInfo(&wmInfo) ? wmInfo.window : NULL;
}
#endif


/*
 *  Display alert
 */

static void display_alert(int title_id, const char *text, int flags)
{
        HWND hMainWnd = GetMainWindowHandle();
        MessageBox(hMainWnd, text, GetString(title_id), MB_OK | flags);
}


/*
 *  Display error alert
 */

void ErrorAlert(const char *text)
{
        if (PrefsFindBool("nogui"))
                return;

        VideoQuitFullScreen();
        display_alert(STR_ERROR_ALERT_TITLE, text, MB_ICONSTOP);
}


/*
 *  Display warning alert
 */

void WarningAlert(const char *text)
{
        if (PrefsFindBool("nogui"))
                return;

        display_alert(STR_WARNING_ALERT_TITLE, text, MB_ICONINFORMATION);
}


/*
 *  Display choice alert
 */

bool ChoiceAlert(const char *text, const char *pos, const char *neg)
{
        printf(GetString(STR_SHELL_WARNING_PREFIX), text);
        return false;   //!!
}
Revision:	1.17
Committed:	2009-08-18T18:26:11Z (15 years, 3 months ago) by asvitkine
Branch:	MAIN
Changes since 1.16:	+10 -6 lines
Log Message:	[Michael Schmitt] Attached is a patch to SheepShaver to fix memory allocation problems when OS X 10.5 is the host. It also relaxes the 512 MB RAM limit on OS X hosts. Problem ------- Some users have been unable to run SheepShaver on OS X 10.5 (Leopard) hosts. The symptom is error "ERROR: Cannot map RAM: File already exists". SheepShaver allocates RAM at fixed addresses. If it is running in "Real" addressing mode, and can't allocate at address 0, then it was hard-coded to allocate the RAM area at 0x20000000. The ROM area as allocated at 0x40800000. The normal configuration is for SheepShaver to run under SDL, which is a Cocoa wrapper. By the time SheepShaver does its memory allocations, the Cocoa application has already started. The result is the SheepShaver memory address space already contains libraries, fonts, Input Managers, and IOKit areas. On Leopard hosts these areas can land on the same addresses SheepShaver needs, so SheepShaver's memory allocation fails. Solution -------- The approach is to change SheepShaver (on Unix & OS X hosts) to allocate the RAM area anywhere it can find the space, rather than at a fixed address. This could result in the RAM allocated higher than the ROM area, which causes a crash. To prevent this from occurring, the RAM and ROM areas are allocated contiguously. Previously the ROM starting address was a constant ROM_BASE, which was used throughout the source files. The ROM start address is now a variable ROMBase. ROMBase is allocated and set by main_.cpp just like RAMBase. A side-effect of this change is that it lifts the 512 MB RAM limit for OS X hosts. The limit was because the fixed RAM and ROM addresses were such that the RAM could only be 512 MB before it overlapped the ROM area. Impact ------ The change to make ROMBase a variable is throughout all hosts & addressing modes. The RAM and ROM areas will only shift when run on Unix & OS X hosts, otherwise the same fixed allocation address is used as before. This change is limited to "Real" addressing mode. Unlike Basilisk II, SheepShaver pre-calculates* the offset for "Direct" addressing mode; the offset is compiled into the program. If the RAM address were allowed to shift, it could result in the RAM area wrapping around address 0. Changes to main_unix.cpp ------------------------ 1. Real addressing mode no longer defines a RAM_BASE constant. 2. The base address of the Mac ROM (ROMBase) is defined and exported by this program. 3. Memory management helper vm_mac_acquire is renamed to vm_mac_acquire_fixed. Added a new memory management helper vm_mac_acquire, which allocates memory at any address. 4. Changed and rearranged the allocation of RAM and ROM areas. Before it worked like this: - Allocate ROM area - If can, attempt to allocate RAM at address zero - If RAM not allocated at 0, allocate at fixed address We still want to try allocating the RAM at zero, and if using DIRECT addressing we're still going to use the fixed addresses. So we don't know where the ROM should be until after we do the RAM. The new logic is: - If can, attempt to allocate RAM at address zero - If RAM not allocated at 0 if REAL addressing allocate RAM and ROM together. The ROM address is aligned to a 1 MB boundary else (direct addressing) allocate RAM at fixed address - If ROM hasn't been allocated yet, allocate at fixed address 5. Calculate ROMBase and ROMBaseHost based on where the ROM was loaded. 6. There is a crash if the RAM is allocated too high. To try and catch this, check if it was allocated higher than the kernel data address. 7. Change subsequent code from using constant ROM_BASE to variable ROMBase. Changes to Other Programs ------------------------- emul_op.cpp, main.cpp, name_registery.cpp, rom_patches.cpp, rsrc_patches.cpp, emul_ppc.cpp, sheepshaver_glue.cpp, ppc-translate-cpp: Change from constant ROM_BASE to variable ROMBase. ppc_asm.S: It was setting register to a hard-coded literal address: 0x40b0d000. Changed to set it to ROMBase + 0x30d000. ppc_asm.tmpl: It defined a macro ASM_LO16 but it assumed that the macro would always be used with operands that included a register specification. This is not true. Moved the register specification from the macro to the macro invocations. main_beos.cpp, main_windows.cpp: Since the subprograms are all expecting a variable ROMBase, all the main_.cpp pgrams have to define and export it. The ROM_BASE constant is moved here for consistency. The mains for beos and windows just allocate the ROM at the same fixed address as before, set ROMBaseHost and ROMBase to that address, and then use ROMBase for the subsequent code. cpu_emulation.h: removed ROM_BASE constant. This value is moved to the main_.cpp modules, to be consistent with RAM_BASE. user_strings_unix.cpp, user_strings_unix.h: Added new error messages related to errors that occur when the RAM and ROM are allocated anywhere.