vl.c

/*
 * QEMU System Emulator
 * 
 * Copyright (c) 2003-2004 Fabrice Bellard
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
#include "vl.h"

#include <getopt.h>
#include <unistd.h>
#include <fcntl.h>
#include <signal.h>
#include <time.h>
#include <malloc.h>
#include <errno.h>
#include <sys/time.h>

#ifndef _WIN32
#include <sys/times.h>
#include <sys/wait.h>
#include <pty.h>
#include <termios.h>
#include <sys/poll.h>
#include <sys/mman.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <linux/if.h>
#include <linux/if_tun.h>
#include <linux/rtc.h>
#endif

#if defined(CONFIG_SLIRP)
#include "libslirp.h"
#endif

#ifdef _WIN32
#include <sys/timeb.h>
#include <windows.h>
#define getopt_long_only getopt_long
#define memalign(align, size) malloc(size)
#endif

#ifdef CONFIG_SDL
/* SDL use the pthreads and they modify sigaction. We don't
   want that. */
#if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 2)
extern void __libc_sigaction();
#define sigaction(sig, act, oact) __libc_sigaction(sig, act, oact)
#else
extern void __sigaction();
#define sigaction(sig, act, oact) __sigaction(sig, act, oact)
#endif
#endif /* CONFIG_SDL */

#include "disas.h"

#include "exec-all.h"

//#define DO_TB_FLUSH

#define DEFAULT_NETWORK_SCRIPT "/etc/qemu-ifup"

//#define DEBUG_UNUSED_IOPORT
//#define DEBUG_IOPORT

#if !defined(CONFIG_SOFTMMU)
#define PHYS_RAM_MAX_SIZE (256 * 1024 * 1024)
#else
#define PHYS_RAM_MAX_SIZE (2047 * 1024 * 1024)
#endif

/* in ms */
#define GUI_REFRESH_INTERVAL 30

/* XXX: use a two level table to limit memory usage */
#define MAX_IOPORTS 65536

const char *bios_dir = CONFIG_QEMU_SHAREDIR;
char phys_ram_file[1024];
CPUState *global_env;
CPUState *cpu_single_env;
void *ioport_opaque[MAX_IOPORTS];
IOPortReadFunc *ioport_read_table[3][MAX_IOPORTS];
IOPortWriteFunc *ioport_write_table[3][MAX_IOPORTS];
BlockDriverState *bs_table[MAX_DISKS], *fd_table[MAX_FD];
int vga_ram_size;
static DisplayState display_state;
int nographic;
int64_t ticks_per_sec;
int boot_device = 'c';
static int ram_size;
static char network_script[1024];
int pit_min_timer_count = 0;
int nb_nics;
NetDriverState nd_table[MAX_NICS];
SerialState *serial_console;
QEMUTimer *gui_timer;
int vm_running;
int audio_enabled = 0;

/***********************************************************/
/* x86 ISA bus support */

target_phys_addr_t isa_mem_base = 0;

uint32_t default_ioport_readb(void *opaque, uint32_t address)
{
#ifdef DEBUG_UNUSED_IOPORT
    fprintf(stderr, "inb: port=0x%04x\n", address);
#endif
    return 0xff;
}

void default_ioport_writeb(void *opaque, uint32_t address, uint32_t data)
{
#ifdef DEBUG_UNUSED_IOPORT
    fprintf(stderr, "outb: port=0x%04x data=0x%02x\n", address, data);
#endif
}

/* default is to make two byte accesses */
uint32_t default_ioport_readw(void *opaque, uint32_t address)
{
    uint32_t data;
    data = ioport_read_table[0][address & (MAX_IOPORTS - 1)](opaque, address);
    data |= ioport_read_table[0][(address + 1) & (MAX_IOPORTS - 1)](opaque, address + 1) << 8;
    return data;
}

void default_ioport_writew(void *opaque, uint32_t address, uint32_t data)
{
    ioport_write_table[0][address & (MAX_IOPORTS - 1)](opaque, address, data & 0xff);
    ioport_write_table[0][(address + 1) & (MAX_IOPORTS - 1)](opaque, address + 1, (data >> 8) & 0xff);
}

uint32_t default_ioport_readl(void *opaque, uint32_t address)
{
#ifdef DEBUG_UNUSED_IOPORT
    fprintf(stderr, "inl: port=0x%04x\n", address);
#endif
    return 0xffffffff;
}

void default_ioport_writel(void *opaque, uint32_t address, uint32_t data)
{
#ifdef DEBUG_UNUSED_IOPORT
    fprintf(stderr, "outl: port=0x%04x data=0x%02x\n", address, data);
#endif
}

void init_ioports(void)
{
    int i;

    for(i = 0; i < MAX_IOPORTS; i++) {
        ioport_read_table[0][i] = default_ioport_readb;
        ioport_write_table[0][i] = default_ioport_writeb;
        ioport_read_table[1][i] = default_ioport_readw;
        ioport_write_table[1][i] = default_ioport_writew;
        ioport_read_table[2][i] = default_ioport_readl;
        ioport_write_table[2][i] = default_ioport_writel;
    }
}

/* size is the word size in byte */
int register_ioport_read(int start, int length, int size, 
                         IOPortReadFunc *func, void *opaque)
{
    int i, bsize;

    if (size == 1) {
        bsize = 0;
    } else if (size == 2) {
        bsize = 1;
    } else if (size == 4) {
        bsize = 2;
    } else {
        hw_error("register_ioport_read: invalid size");
        return -1;
    }
    for(i = start; i < start + length; i += size) {
        ioport_read_table[bsize][i] = func;
        if (ioport_opaque[i] != NULL && ioport_opaque[i] != opaque)
            hw_error("register_ioport_read: invalid opaque");
        ioport_opaque[i] = opaque;
    }
    return 0;
}

/* size is the word size in byte */
int register_ioport_write(int start, int length, int size, 
                          IOPortWriteFunc *func, void *opaque)
{
    int i, bsize;

    if (size == 1) {
        bsize = 0;
    } else if (size == 2) {
        bsize = 1;
    } else if (size == 4) {
        bsize = 2;
    } else {
        hw_error("register_ioport_write: invalid size");
        return -1;
    }
    for(i = start; i < start + length; i += size) {
        ioport_write_table[bsize][i] = func;
        if (ioport_opaque[i] != NULL && ioport_opaque[i] != opaque)
            hw_error("register_ioport_read: invalid opaque");
        ioport_opaque[i] = opaque;
    }
    return 0;
}

void pstrcpy(char *buf, int buf_size, const char *str)
{
    int c;
    char *q = buf;

    if (buf_size <= 0)
        return;

    for(;;) {
        c = *str++;
        if (c == 0 || q >= buf + buf_size - 1)
            break;
        *q++ = c;
    }
    *q = '\0';
}

/* strcat and truncate. */
char *pstrcat(char *buf, int buf_size, const char *s)
{
    int len;
    len = strlen(buf);
    if (len < buf_size) 
        pstrcpy(buf + len, buf_size - len, s);
    return buf;
}

/* return the size or -1 if error */
int load_image(const char *filename, uint8_t *addr)
{
    int fd, size;
    fd = open(filename, O_RDONLY | O_BINARY);
    if (fd < 0)
        return -1;
    size = lseek(fd, 0, SEEK_END);
    lseek(fd, 0, SEEK_SET);
    if (read(fd, addr, size) != size) {
        close(fd);
        return -1;
    }
    close(fd);
    return size;
}

void cpu_outb(CPUState *env, int addr, int val)
{
    addr &= (MAX_IOPORTS - 1);
#ifdef DEBUG_IOPORT
    if (loglevel & CPU_LOG_IOPORT)
        fprintf(logfile, "outb: %04x %02x\n", addr, val);
#endif    
    ioport_write_table[0][addr](ioport_opaque[addr], addr, val);
}

void cpu_outw(CPUState *env, int addr, int val)
{
    addr &= (MAX_IOPORTS - 1);
#ifdef DEBUG_IOPORT
    if (loglevel & CPU_LOG_IOPORT)
        fprintf(logfile, "outw: %04x %04x\n", addr, val);
#endif    
    ioport_write_table[1][addr](ioport_opaque[addr], addr, val);
}

void cpu_outl(CPUState *env, int addr, int val)
{
    addr &= (MAX_IOPORTS - 1);
#ifdef DEBUG_IOPORT
    if (loglevel & CPU_LOG_IOPORT)
        fprintf(logfile, "outl: %04x %08x\n", addr, val);
#endif
    ioport_write_table[2][addr](ioport_opaque[addr], addr, val);
}

int cpu_inb(CPUState *env, int addr)
{
    int val;
    addr &= (MAX_IOPORTS - 1);
    val = ioport_read_table[0][addr](ioport_opaque[addr], addr);
#ifdef DEBUG_IOPORT
    if (loglevel & CPU_LOG_IOPORT)
        fprintf(logfile, "inb : %04x %02x\n", addr, val);
#endif
    return val;
}

int cpu_inw(CPUState *env, int addr)
{
    int val;
    addr &= (MAX_IOPORTS - 1);
    val = ioport_read_table[1][addr](ioport_opaque[addr], addr);
#ifdef DEBUG_IOPORT
    if (loglevel & CPU_LOG_IOPORT)
        fprintf(logfile, "inw : %04x %04x\n", addr, val);
#endif
    return val;
}

int cpu_inl(CPUState *env, int addr)
{
    int val;
    addr &= (MAX_IOPORTS - 1);
    val = ioport_read_table[2][addr](ioport_opaque[addr], addr);
#ifdef DEBUG_IOPORT
    if (loglevel & CPU_LOG_IOPORT)
        fprintf(logfile, "inl : %04x %08x\n", addr, val);
#endif
    return val;
}

/***********************************************************/
void hw_error(const char *fmt, ...)
{
    va_list ap;

    va_start(ap, fmt);
    fprintf(stderr, "qemu: hardware error: ");
    vfprintf(stderr, fmt, ap);
    fprintf(stderr, "\n");
#ifdef TARGET_I386
    cpu_x86_dump_state(global_env, stderr, X86_DUMP_FPU | X86_DUMP_CCOP);
#else
    cpu_dump_state(global_env, stderr, 0);
#endif
    va_end(ap);
    abort();
}

/***********************************************************/
/* timers */

#if defined(__powerpc__)

static inline uint32_t get_tbl(void) 
{
    uint32_t tbl;
    asm volatile("mftb %0" : "=r" (tbl));
    return tbl;
}

static inline uint32_t get_tbu(void) 
{
	uint32_t tbl;
	asm volatile("mftbu %0" : "=r" (tbl));
	return tbl;
}

int64_t cpu_get_real_ticks(void)
{
    uint32_t l, h, h1;
    /* NOTE: we test if wrapping has occurred */
    do {
        h = get_tbu();
        l = get_tbl();
        h1 = get_tbu();
    } while (h != h1);
    return ((int64_t)h << 32) | l;
}

#elif defined(__i386__)

int64_t cpu_get_real_ticks(void)
{
    int64_t val;
    asm volatile ("rdtsc" : "=A" (val));
    return val;
}

#elif defined(__x86_64__)

int64_t cpu_get_real_ticks(void)
{
    uint32_t low,high;
    int64_t val;
    asm volatile("rdtsc" : "=a" (low), "=d" (high));
    val = high;
    val <<= 32;
    val |= low;
    return val;
}

#else
#error unsupported CPU
#endif

static int64_t cpu_ticks_offset;
static int cpu_ticks_enabled;

static inline int64_t cpu_get_ticks(void)
{
    if (!cpu_ticks_enabled) {
        return cpu_ticks_offset;
    } else {
        return cpu_get_real_ticks() + cpu_ticks_offset;
    }
}

/* enable cpu_get_ticks() */
void cpu_enable_ticks(void)
{
    if (!cpu_ticks_enabled) {
        cpu_ticks_offset -= cpu_get_real_ticks();
        cpu_ticks_enabled = 1;
    }
}

/* disable cpu_get_ticks() : the clock is stopped. You must not call
   cpu_get_ticks() after that.  */
void cpu_disable_ticks(void)
{
    if (cpu_ticks_enabled) {
        cpu_ticks_offset = cpu_get_ticks();
        cpu_ticks_enabled = 0;
    }
}

static int64_t get_clock(void)
{
#ifdef _WIN32
    struct _timeb tb;
    _ftime(&tb);
    return ((int64_t)tb.time * 1000 + (int64_t)tb.millitm) * 1000;
#else
    struct timeval tv;
    gettimeofday(&tv, NULL);
    return tv.tv_sec * 1000000LL + tv.tv_usec;
#endif
}

void cpu_calibrate_ticks(void)
{
    int64_t usec, ticks;

    usec = get_clock();
    ticks = cpu_get_real_ticks();
#ifdef _WIN32
    Sleep(50);
#else
    usleep(50 * 1000);
#endif
    usec = get_clock() - usec;
    ticks = cpu_get_real_ticks() - ticks;
    ticks_per_sec = (ticks * 1000000LL + (usec >> 1)) / usec;
}

/* compute with 96 bit intermediate result: (a*b)/c */
uint64_t muldiv64(uint64_t a, uint32_t b, uint32_t c)
{
    union {
        uint64_t ll;
        struct {
#ifdef WORDS_BIGENDIAN
            uint32_t high, low;
#else
            uint32_t low, high;
#endif            
        } l;
    } u, res;
    uint64_t rl, rh;

    u.ll = a;
    rl = (uint64_t)u.l.low * (uint64_t)b;
    rh = (uint64_t)u.l.high * (uint64_t)b;
    rh += (rl >> 32);
    res.l.high = rh / c;
    res.l.low = (((rh % c) << 32) + (rl & 0xffffffff)) / c;
    return res.ll;
}

#define QEMU_TIMER_REALTIME 0
#define QEMU_TIMER_VIRTUAL  1

struct QEMUClock {
    int type;
    /* XXX: add frequency */
};

struct QEMUTimer {
    QEMUClock *clock;
    int64_t expire_time;
    QEMUTimerCB *cb;
    void *opaque;
    struct QEMUTimer *next;
};

QEMUClock *rt_clock;
QEMUClock *vm_clock;

static QEMUTimer *active_timers[2];
#ifdef _WIN32
static MMRESULT timerID;
#else
/* frequency of the times() clock tick */
static int timer_freq;
#endif

QEMUClock *qemu_new_clock(int type)
{
    QEMUClock *clock;
    clock = qemu_mallocz(sizeof(QEMUClock));
    if (!clock)
        return NULL;
    clock->type = type;
    return clock;
}

QEMUTimer *qemu_new_timer(QEMUClock *clock, QEMUTimerCB *cb, void *opaque)
{
    QEMUTimer *ts;

    ts = qemu_mallocz(sizeof(QEMUTimer));
    ts->clock = clock;
    ts->cb = cb;
    ts->opaque = opaque;
    return ts;
}

void qemu_free_timer(QEMUTimer *ts)
{
    qemu_free(ts);
}

/* stop a timer, but do not dealloc it */
void qemu_del_timer(QEMUTimer *ts)
{
    QEMUTimer **pt, *t;

    /* NOTE: this code must be signal safe because
       qemu_timer_expired() can be called from a signal. */
    pt = &active_timers[ts->clock->type];
    for(;;) {
        t = *pt;
        if (!t)
            break;
        if (t == ts) {
            *pt = t->next;
            break;
        }
        pt = &t->next;
    }
}

/* modify the current timer so that it will be fired when current_time
   >= expire_time. The corresponding callback will be called. */
void qemu_mod_timer(QEMUTimer *ts, int64_t expire_time)
{
    QEMUTimer **pt, *t;

    qemu_del_timer(ts);

    /* add the timer in the sorted list */
    /* NOTE: this code must be signal safe because
       qemu_timer_expired() can be called from a signal. */
    pt = &active_timers[ts->clock->type];
    for(;;) {
        t = *pt;
        if (!t)
            break;
        if (t->expire_time > expire_time) 
            break;
        pt = &t->next;
    }
    ts->expire_time = expire_time;
    ts->next = *pt;
    *pt = ts;
}

int qemu_timer_pending(QEMUTimer *ts)
{
    QEMUTimer *t;
    for(t = active_timers[ts->clock->type]; t != NULL; t = t->next) {
        if (t == ts)
            return 1;
    }
    return 0;
}

static inline int qemu_timer_expired(QEMUTimer *timer_head, int64_t current_time)
{
    if (!timer_head)
        return 0;
    return (timer_head->expire_time <= current_time);
}

static void qemu_run_timers(QEMUTimer **ptimer_head, int64_t current_time)
{
    QEMUTimer *ts;
    
    for(;;) {
        ts = *ptimer_head;
        if (ts->expire_time > current_time)
            break;
        /* remove timer from the list before calling the callback */
        *ptimer_head = ts->next;
        ts->next = NULL;
        
        /* run the callback (the timer list can be modified) */
        ts->cb(ts->opaque);
    }
}

int64_t qemu_get_clock(QEMUClock *clock)
{
    switch(clock->type) {
    case QEMU_TIMER_REALTIME:
#ifdef _WIN32
        return GetTickCount();
#else
        /* XXX: portability among Linux hosts */
        if (timer_freq == 100) {
            return times(NULL) * 10;
        } else {
            return ((int64_t)times(NULL) * 1000) / timer_freq;
        }
#endif
    default:
    case QEMU_TIMER_VIRTUAL:
        return cpu_get_ticks();
    }
}

/* save a timer */
void qemu_put_timer(QEMUFile *f, QEMUTimer *ts)
{
    uint64_t expire_time;

    if (qemu_timer_pending(ts)) {
        expire_time = ts->expire_time;
    } else {
        expire_time = -1;
    }
    qemu_put_be64(f, expire_time);
}

void qemu_get_timer(QEMUFile *f, QEMUTimer *ts)
{
    uint64_t expire_time;

    expire_time = qemu_get_be64(f);
    if (expire_time != -1) {
        qemu_mod_timer(ts, expire_time);
    } else {
        qemu_del_timer(ts);
    }
}

static void timer_save(QEMUFile *f, void *opaque)
{
    if (cpu_ticks_enabled) {
        hw_error("cannot save state if virtual timers are running");
    }
    qemu_put_be64s(f, &cpu_ticks_offset);
    qemu_put_be64s(f, &ticks_per_sec);
}

static int timer_load(QEMUFile *f, void *opaque, int version_id)
{
    if (version_id != 1)
        return -EINVAL;
    if (cpu_ticks_enabled) {
        return -EINVAL;
    }
    qemu_get_be64s(f, &cpu_ticks_offset);
    qemu_get_be64s(f, &ticks_per_sec);
    return 0;
}

#ifdef _WIN32
void CALLBACK host_alarm_handler(UINT uTimerID, UINT uMsg, 
                                 DWORD_PTR dwUser, DWORD_PTR dw1, DWORD_PTR dw2)
#else
static void host_alarm_handler(int host_signum)
#endif
{
    if (qemu_timer_expired(active_timers[QEMU_TIMER_VIRTUAL],
                           qemu_get_clock(vm_clock)) ||
        qemu_timer_expired(active_timers[QEMU_TIMER_REALTIME],
                           qemu_get_clock(rt_clock))) {
        /* stop the cpu because a timer occured */
        cpu_interrupt(global_env, CPU_INTERRUPT_EXIT);
    }
}

#ifndef _WIN32

#define RTC_FREQ 1024

static int rtc_fd;
    
static int start_rtc_timer(void)
{
    rtc_fd = open("/dev/rtc", O_RDONLY);
    if (rtc_fd < 0)
        return -1;
    if (ioctl(rtc_fd, RTC_IRQP_SET, RTC_FREQ) < 0) {
        fprintf(stderr, "Could not configure '/dev/rtc' to have a 1024 Hz timer. This is not a fatal\n"
                "error, but for better emulation accuracy either use a 2.6 host Linux kernel or\n"
                "type 'echo 1024 > /proc/sys/dev/rtc/max-user-freq' as root.\n");
        goto fail;
    }
    if (ioctl(rtc_fd, RTC_PIE_ON, 0) < 0) {
    fail:
        close(rtc_fd);
        return -1;
    }
    pit_min_timer_count = PIT_FREQ / RTC_FREQ;
    return 0;
}

#endif

static void init_timers(void)
{
    rt_clock = qemu_new_clock(QEMU_TIMER_REALTIME);
    vm_clock = qemu_new_clock(QEMU_TIMER_VIRTUAL);

#ifdef _WIN32
    {
        int count=0;
        timerID = timeSetEvent(10,    // interval (ms)
                               0,     // resolution
                               host_alarm_handler, // function
                               (DWORD)&count,  // user parameter
                               TIME_PERIODIC | TIME_CALLBACK_FUNCTION);
 	if( !timerID ) {
            perror("failed timer alarm");
            exit(1);
 	}
    }
    pit_min_timer_count = ((uint64_t)10000 * PIT_FREQ) / 1000000;
#else
    {
        struct sigaction act;
        struct itimerval itv;
        
        /* get times() syscall frequency */
        timer_freq = sysconf(_SC_CLK_TCK);
        
        /* timer signal */
        sigfillset(&act.sa_mask);
        act.sa_flags = 0;
#if defined (TARGET_I386) && defined(USE_CODE_COPY)
        act.sa_flags |= SA_ONSTACK;
#endif
        act.sa_handler = host_alarm_handler;
        sigaction(SIGALRM, &act, NULL);

        itv.it_interval.tv_sec = 0;
        itv.it_interval.tv_usec = 1000;
        itv.it_value.tv_sec = 0;
        itv.it_value.tv_usec = 10 * 1000;
        setitimer(ITIMER_REAL, &itv, NULL);
        /* we probe the tick duration of the kernel to inform the user if
           the emulated kernel requested a too high timer frequency */
        getitimer(ITIMER_REAL, &itv);

        if (itv.it_interval.tv_usec > 1000) {
            /* try to use /dev/rtc to have a faster timer */
            if (start_rtc_timer() < 0)
                goto use_itimer;
            /* disable itimer */
            itv.it_interval.tv_sec = 0;
            itv.it_interval.tv_usec = 0;
            itv.it_value.tv_sec = 0;
            itv.it_value.tv_usec = 0;
            setitimer(ITIMER_REAL, &itv, NULL);

            /* use the RTC */
            sigaction(SIGIO, &act, NULL);
            fcntl(rtc_fd, F_SETFL, O_ASYNC);
            fcntl(rtc_fd, F_SETOWN, getpid());
        } else {
        use_itimer:
            pit_min_timer_count = ((uint64_t)itv.it_interval.tv_usec * 
                                   PIT_FREQ) / 1000000;
        }
    }
#endif
}

void quit_timers(void)
{
#ifdef _WIN32
    timeKillEvent(timerID);
#endif
}

/***********************************************************/
/* serial device */

#ifdef _WIN32

int serial_open_device(void)
{
    return -1;
}

#else

int serial_open_device(void)
{
    char slave_name[1024];
    int master_fd, slave_fd;

    if (serial_console == NULL && nographic) {
        /* use console for serial port */
        return 0;
    } else {
        if (openpty(&master_fd, &slave_fd, slave_name, NULL, NULL) < 0) {
            fprintf(stderr, "warning: could not create pseudo terminal for serial port\n");
            return -1;
        }
        fprintf(stderr, "Serial port redirected to %s\n", slave_name);
        return master_fd;
    }
}

#endif

/***********************************************************/
/* Linux network device redirectors */

void hex_dump(FILE *f, const uint8_t *buf, int size)
{
    int len, i, j, c;

    for(i=0;i<size;i+=16) {
        len = size - i;
        if (len > 16)
            len = 16;
        fprintf(f, "%08x ", i);
        for(j=0;j<16;j++) {
            if (j < len)
                fprintf(f, " %02x", buf[i+j]);
            else
                fprintf(f, "   ");
        }
        fprintf(f, " ");
        for(j=0;j<len;j++) {
            c = buf[i+j];
            if (c < ' ' || c > '~')
                c = '.';
            fprintf(f, "%c", c);
        }
        fprintf(f, "\n");
    }
}

void qemu_send_packet(NetDriverState *nd, const uint8_t *buf, int size)
{
    nd->send_packet(nd, buf, size);
}

void qemu_add_read_packet(NetDriverState *nd, IOCanRWHandler *fd_can_read, 
                          IOReadHandler *fd_read, void *opaque)
{
    nd->add_read_packet(nd, fd_can_read, fd_read, opaque);
}

/* dummy network adapter */

static void dummy_send_packet(NetDriverState *nd, const uint8_t *buf, int size)
{
}

static void dummy_add_read_packet(NetDriverState *nd, 
                                  IOCanRWHandler *fd_can_read, 
                                  IOReadHandler *fd_read, void *opaque)
{
}

static int net_dummy_init(NetDriverState *nd)
{
    nd->send_packet = dummy_send_packet;
    nd->add_read_packet = dummy_add_read_packet;
    pstrcpy(nd->ifname, sizeof(nd->ifname), "dummy");
    return 0;
}

#if defined(CONFIG_SLIRP)

/* slirp network adapter */

static void *slirp_fd_opaque;
static IOCanRWHandler *slirp_fd_can_read;
static IOReadHandler *slirp_fd_read;
static int slirp_inited;

int slirp_can_output(void)
{
    return slirp_fd_can_read(slirp_fd_opaque);
}

void slirp_output(const uint8_t *pkt, int pkt_len)
{
#if 0
    printf("output:\n");
    hex_dump(stdout, pkt, pkt_len);
#endif
    slirp_fd_read(slirp_fd_opaque, pkt, pkt_len);
}

static void slirp_send_packet(NetDriverState *nd, const uint8_t *buf, int size)
{
#if 0
    printf("input:\n");
    hex_dump(stdout, buf, size);
#endif
    slirp_input(buf, size);
}

static void slirp_add_read_packet(NetDriverState *nd, 
                                  IOCanRWHandler *fd_can_read, 
                                  IOReadHandler *fd_read, void *opaque)
{
    slirp_fd_opaque = opaque;
    slirp_fd_can_read = fd_can_read;
    slirp_fd_read = fd_read;
}

static int net_slirp_init(NetDriverState *nd)
{
    if (!slirp_inited) {
        slirp_inited = 1;
        slirp_init();
    }
    nd->send_packet = slirp_send_packet;
    nd->add_read_packet = slirp_add_read_packet;
    pstrcpy(nd->ifname, sizeof(nd->ifname), "slirp");
    return 0;
}

#endif /* CONFIG_SLIRP */

#if !defined(_WIN32)

static int tun_open(char *ifname, int ifname_size)
{
    struct ifreq ifr;
    int fd, ret;
    
    fd = open("/dev/net/tun", O_RDWR);
    if (fd < 0) {
        fprintf(stderr, "warning: could not open /dev/net/tun: no virtual network emulation\n");
        return -1;
    }
    memset(&ifr, 0, sizeof(ifr));
    ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
    pstrcpy(ifr.ifr_name, IFNAMSIZ, "tun%d");
    ret = ioctl(fd, TUNSETIFF, (void *) &ifr);
    if (ret != 0) {
        fprintf(stderr, "warning: could not configure /dev/net/tun: no virtual network emulation\n");
        close(fd);
        return -1;
    }
    printf("Connected to host network interface: %s\n", ifr.ifr_name);
    pstrcpy(ifname, ifname_size, ifr.ifr_name);
    fcntl(fd, F_SETFL, O_NONBLOCK);
    return fd;
}

static void tun_send_packet(NetDriverState *nd, const uint8_t *buf, int size)
{
    write(nd->fd, buf, size);
}

static void tun_add_read_packet(NetDriverState *nd, 
                                IOCanRWHandler *fd_can_read, 
                                IOReadHandler *fd_read, void *opaque)
{
    qemu_add_fd_read_handler(nd->fd, fd_can_read, fd_read, opaque);
}

static int net_tun_init(NetDriverState *nd)
{
    int pid, status;
    char *args[3];
    char **parg;

    nd->fd = tun_open(nd->ifname, sizeof(nd->ifname));
    if (nd->fd < 0)
        return -1;

    /* try to launch network init script */
    pid = fork();
    if (pid >= 0) {
        if (pid == 0) {
            parg = args;
            *parg++ = network_script;
            *parg++ = nd->ifname;
            *parg++ = NULL;
            execv(network_script, args);
            exit(1);
        }
        while (waitpid(pid, &status, 0) != pid);
        if (!WIFEXITED(status) ||
            WEXITSTATUS(status) != 0) {
            fprintf(stderr, "%s: could not launch network script\n",
                    network_script);
        }
    }
    nd->send_packet = tun_send_packet;
    nd->add_read_packet = tun_add_read_packet;
    return 0;
}

static int net_fd_init(NetDriverState *nd, int fd)
{
    nd->fd = fd;
    nd->send_packet = tun_send_packet;
    nd->add_read_packet = tun_add_read_packet;
    pstrcpy(nd->ifname, sizeof(nd->ifname), "tunfd");
    return 0;
}

#endif /* !_WIN32 */

/***********************************************************/
/* dumb display */

#ifdef _WIN32

static void term_exit(void)
{
}

static void term_init(void)
{
}

#else

/* init terminal so that we can grab keys */
static struct termios oldtty;

static void term_exit(void)
{
    tcsetattr (0, TCSANOW, &oldtty);
}

static void term_init(void)
{
    struct termios tty;

    tcgetattr (0, &tty);
    oldtty = tty;

    tty.c_iflag &= ~(IGNBRK|BRKINT|PARMRK|ISTRIP
                          |INLCR|IGNCR|ICRNL|IXON);
    tty.c_oflag |= OPOST;
    tty.c_lflag &= ~(ECHO|ECHONL|ICANON|IEXTEN);
    /* if graphical mode, we allow Ctrl-C handling */
    if (nographic)
        tty.c_lflag &= ~ISIG;
    tty.c_cflag &= ~(CSIZE|PARENB);
    tty.c_cflag |= CS8;
    tty.c_cc[VMIN] = 1;
    tty.c_cc[VTIME] = 0;
    
    tcsetattr (0, TCSANOW, &tty);

    atexit(term_exit);

    fcntl(0, F_SETFL, O_NONBLOCK);
}

#endif

static void dumb_update(DisplayState *ds, int x, int y, int w, int h)
{
}

static void dumb_resize(DisplayState *ds, int w, int h)
{
}

static void dumb_refresh(DisplayState *ds)
{
    vga_update_display();
}

void dumb_display_init(DisplayState *ds)
{
    ds->data = NULL;
    ds->linesize = 0;
    ds->depth = 0;
    ds->dpy_update = dumb_update;
    ds->dpy_resize = dumb_resize;
    ds->dpy_refresh = dumb_refresh;
}

#if !defined(CONFIG_SOFTMMU)
/***********************************************************/
/* cpu signal handler */
static void host_segv_handler(int host_signum, siginfo_t *info, 
                              void *puc)
{
    if (cpu_signal_handler(host_signum, info, puc))
        return;
    term_exit();
    abort();
}
#endif

/***********************************************************/
/* I/O handling */

#define MAX_IO_HANDLERS 64

typedef struct IOHandlerRecord {
    int fd;
    IOCanRWHandler *fd_can_read;
    IOReadHandler *fd_read;
    void *opaque;
    /* temporary data */
    struct pollfd *ufd;
    int max_size;
    struct IOHandlerRecord *next;
} IOHandlerRecord;

static IOHandlerRecord *first_io_handler;

int qemu_add_fd_read_handler(int fd, IOCanRWHandler *fd_can_read, 
                             IOReadHandler *fd_read, void *opaque)
{
    IOHandlerRecord *ioh;

    ioh = qemu_mallocz(sizeof(IOHandlerRecord));
    if (!ioh)
        return -1;
    ioh->fd = fd;
    ioh->fd_can_read = fd_can_read;
    ioh->fd_read = fd_read;
    ioh->opaque = opaque;
    ioh->next = first_io_handler;
    first_io_handler = ioh;
    return 0;
}

void qemu_del_fd_read_handler(int fd)
{
    IOHandlerRecord **pioh, *ioh;

    pioh = &first_io_handler;
    for(;;) {
        ioh = *pioh;
        if (ioh == NULL)
            break;
        if (ioh->fd == fd) {
            *pioh = ioh->next;
            break;
        }
        pioh = &ioh->next;
    }
}

/***********************************************************/
/* savevm/loadvm support */

void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size)
{
    fwrite(buf, 1, size, f);
}

void qemu_put_byte(QEMUFile *f, int v)
{
    fputc(v, f);
}

void qemu_put_be16(QEMUFile *f, unsigned int v)
{
    qemu_put_byte(f, v >> 8);
    qemu_put_byte(f, v);
}

voi