qemu-img.c

qemu虚拟机代码

/*
 * create a COW disk image
 * 
 * Copyright (c) 2003 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"

void *get_mmap_addr(unsigned long size)
{
    return NULL;
}

void qemu_free(void *ptr)
{
    free(ptr);
}

void *qemu_malloc(size_t size)
{
    return malloc(size);
}

void *qemu_mallocz(size_t size)
{
    void *ptr;
    ptr = qemu_malloc(size);
    if (!ptr)
        return NULL;
    memset(ptr, 0, size);
    return ptr;
}

char *qemu_strdup(const char *str)
{
    char *ptr;
    ptr = qemu_malloc(strlen(str) + 1);
    if (!ptr)
        return NULL;
    strcpy(ptr, str);
    return ptr;
}

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;
}

int strstart(const char *str, const char *val, const char **ptr)
{
    const char *p, *q;
    p = str;
    q = val;
    while (*q != '\0') {
        if (*p != *q)
            return 0;
        p++;
        q++;
    }
    if (ptr)
        *ptr = p;
    return 1;
}

void term_printf(const char *fmt, ...)
{
    va_list ap;
    va_start(ap, fmt);
    vprintf(fmt, ap);
    va_end(ap);
}

void __attribute__((noreturn)) error(const char *fmt, ...) 
{
    va_list ap;
    va_start(ap, fmt);
    fprintf(stderr, "qemu-img: ");
    vfprintf(stderr, fmt, ap);
    fprintf(stderr, "\n");
    exit(1);
    va_end(ap);
}

static void format_print(void *opaque, const char *name)
{
    printf(" %s", name);
}

void help(void)
{
    printf("qemu-img version " QEMU_VERSION ", Copyright (c) 2004-2005 Fabrice Bellard\n"
           "usage: qemu-img command [command options]\n"
           "QEMU disk image utility\n"
           "\n"
           "Command syntax:\n"
           "  create [-e] [-b base_image] [-f fmt] filename [size]\n"
           "  commit [-f fmt] filename\n"
           "  convert [-c] [-e] [-f fmt] filename [-O output_fmt] output_filename\n"
           "  info [-f fmt] filename\n"
           "\n"
           "Command parameters:\n"
           "  'filename' is a disk image filename\n"
           "  'base_image' is the read-only disk image which is used as base for a copy on\n"
           "    write image; the copy on write image only stores the modified data\n"
           "  'fmt' is the disk image format. It is guessed automatically in most cases\n"
           "  'size' is the disk image size in kilobytes. Optional suffixes 'M' (megabyte)\n"
           "    and 'G' (gigabyte) are supported\n"
           "  'output_filename' is the destination disk image filename\n"
           "  'output_fmt' is the destination format\n"
           "  '-c' indicates that target image must be compressed (qcow format only)\n"
           "  '-e' indicates that the target image must be encrypted (qcow format only)\n"
           );
    printf("\nSupported format:");
    bdrv_iterate_format(format_print, NULL);
    printf("\n");
    exit(1);
}


#define NB_SUFFIXES 4

static void get_human_readable_size(char *buf, int buf_size, int64_t size)
{
    char suffixes[NB_SUFFIXES] = "KMGT";
    int64_t base;
    int i;

    if (size <= 999) {
        snprintf(buf, buf_size, "%lld", (long long) size);
    } else {
        base = 1024;
        for(i = 0; i < NB_SUFFIXES; i++) {
            if (size < (10 * base)) {
                snprintf(buf, buf_size, "%0.1f%c", 
                         (double)size / base,
                         suffixes[i]);
                break;
            } else if (size < (1000 * base) || i == (NB_SUFFIXES - 1)) {
                snprintf(buf, buf_size, "%lld%c", 
                         (long long) ((size + (base >> 1)) / base),
                         suffixes[i]);
                break;
            }
            base = base * 1024;
        }
    }
}

#if defined(WIN32)
/* XXX: put correct support for win32 */
static int read_password(char *buf, int buf_size)
{
    int c, i;
    printf("Password: ");
    fflush(stdout);
    i = 0;
    for(;;) {
        c = getchar();
        if (c == '\n')
            break;
        if (i < (buf_size - 1))
            buf[i++] = c;
    }
    buf[i] = '\0';
    return 0;
}

#else

#include <termios.h>

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);
    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);
}

int read_password(char *buf, int buf_size)
{
    uint8_t ch;
    int i, ret;

    printf("password: ");
    fflush(stdout);
    term_init();
    i = 0;
    for(;;) {
        ret = read(0, &ch, 1);
        if (ret == -1) {
            if (errno == EAGAIN || errno == EINTR) {
                continue;
            } else {
                ret = -1;
                break;
            }
        } else if (ret == 0) {
            ret = -1;
            break;
        } else {
            if (ch == '\r') {
                ret = 0;
                break;
            }
            if (i < (buf_size - 1))
                buf[i++] = ch;
        }
    }
    term_exit();
    buf[i] = '\0';
    printf("\n");
    return ret;
}
#endif

static BlockDriverState *bdrv_new_open(const char *filename,
                                       const char *fmt)
{
    BlockDriverState *bs;
    BlockDriver *drv;
    char password[256];

    bs = bdrv_new("");
    if (!bs)
        error("Not enough memory");
    if (fmt) {
        drv = bdrv_find_format(fmt);
        if (!drv)
            error("Unknown file format '%s'", fmt);
    } else {
        drv = NULL;
    }
    if (bdrv_open2(bs, filename, 0, drv) < 0) {
        error("Could not open '%s'", filename);
    }
    if (bdrv_is_encrypted(bs)) {
        printf("Disk image '%s' is encrypted.\n", filename);
        if (read_password(password, sizeof(password)) < 0)
            error("No password given");
        if (bdrv_set_key(bs, password) < 0)
            error("invalid password");
    }
    return bs;
}

static int img_create(int argc, char **argv)
{
    int c, ret, encrypted;
    const char *fmt = "raw";
    const char *filename;
    const char *base_filename = NULL;
    int64_t size;
    const char *p;
    BlockDriver *drv;
    
    encrypted = 0;
    for(;;) {
        c = getopt(argc, argv, "b:f:he");
        if (c == -1)
            break;
        switch(c) {
        case 'h':
            help();
            break;
        case 'b':
            base_filename = optarg;
            break;
        case 'f':
            fmt = optarg;
            break;
        case 'e':
            encrypted = 1;
            break;
        }
    }
    if (optind >= argc) 
        help();
    filename = argv[optind++];
    size = 0;
    if (base_filename) {
        BlockDriverState *bs;
        bs = bdrv_new_open(base_filename, NULL);
        bdrv_get_geometry(bs, &size);
        size *= 512;
        bdrv_delete(bs);
    } else {
        if (optind >= argc)
            help();
        p = argv[optind];
        size = strtoul(p, (char **)&p, 0);