Archipelago » qemu

/*

 * QEMU disk image utility

 *

 * Copyright (c) 2003-2008 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 "qemu-common.h"

#include "qemu-option.h"

#include "qemu-error.h"

#include "osdep.h"

#include "sysemu.h"

#include "block_int.h"

#include <stdio.h>

#ifdef _WIN32

#include <windows.h>

#endif

typedef struct img_cmd_t {

    const char *name;

    int (*handler)(int argc, char **argv);

} img_cmd_t;

/* Default to cache=writeback as data integrity is not important for qemu-tcg. */

#define BDRV_O_FLAGS BDRV_O_CACHE_WB

static void format_print(void *opaque, const char *name)

{

    printf(" %s", name);

}

/* Please keep in synch with qemu-img.texi */

static void help(void)

{

    const char *help_msg =

           "qemu-img version " QEMU_VERSION ", Copyright (c) 2004-2008 Fabrice Bellard\n"

           "usage: qemu-img command [command options]\n"

           "QEMU disk image utility\n"

           "\n"

           "Command syntax:\n"

#define DEF(option, callback, arg_string)        \

           "  " arg_string "\n"

#include "qemu-img-cmds.h"

#undef DEF

#undef GEN_DOCS

           "\n"

           "Command parameters:\n"

           "  'filename' is a disk image filename\n"

           "  'fmt' is the disk image format. It is guessed automatically in most cases\n"

           "  'size' is the disk image size in bytes. Optional suffixes\n"

           "    'k' or 'K' (kilobyte, 1024), 'M' (megabyte, 1024k), 'G' (gigabyte, 1024M)\n"

           "    and T (terabyte, 1024G) are supported. 'b' is ignored.\n"

           "  'output_filename' is the destination disk image filename\n"

           "  'output_fmt' is the destination format\n"

           "  'options' is a comma separated list of format specific options in a\n"

           "    name=value format. Use -o ? for an overview of the options supported by the\n"

           "    used format\n"

           "  '-c' indicates that target image must be compressed (qcow format only)\n"

           "  '-u' enables unsafe rebasing. It is assumed that old and new backing file\n"

           "       match exactly. The image doesn't need a working backing file before\n"

           "       rebasing in this case (useful for renaming the backing file)\n"

           "  '-h' with or without a command shows this help and lists the supported formats\n"

           "\n"

           "Parameters to snapshot subcommand:\n"

           "  'snapshot' is the name of the snapshot to create, apply or delete\n"

           "  '-a' applies a snapshot (revert disk to saved state)\n"

           "  '-c' creates a snapshot\n"

           "  '-d' deletes a snapshot\n"

           "  '-l' lists all snapshots in the given image\n";

    printf("%s\nSupported formats:", help_msg);

    bdrv_iterate_format(format_print, NULL);

    printf("\n");

    exit(1);

}

#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);

}

static 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 int print_block_option_help(const char *filename, const char *fmt)

{

    BlockDriver *drv, *proto_drv;

    QEMUOptionParameter *create_options = NULL;

    /* Find driver and parse its options */

    drv = bdrv_find_format(fmt);

    if (!drv) {

        error_report("Unknown file format '%s'", fmt);

        return 1;

    }

    proto_drv = bdrv_find_protocol(filename);

    if (!proto_drv) {

        error_report("Unknown protocol '%s'", filename);

        return 1;

    }

    create_options = append_option_parameters(create_options,

                                              drv->create_options);

    create_options = append_option_parameters(create_options,

                                              proto_drv->create_options);

    print_option_help(create_options);

    free_option_parameters(create_options);

    return 0;

}

static BlockDriverState *bdrv_new_open(const char *filename,

                                       const char *fmt,

                                       int flags)

{

    BlockDriverState *bs;

    BlockDriver *drv;

    char password[256];

    bs = bdrv_new("");

    if (fmt) {

        drv = bdrv_find_format(fmt);

        if (!drv) {

            error_report("Unknown file format '%s'", fmt);

            goto fail;

        }

    } else {

        drv = NULL;

    }

    if (bdrv_open(bs, filename, flags, drv) < 0) {

        error_report("Could not open '%s'", filename);

        goto fail;

    }

    if (bdrv_is_encrypted(bs)) {

        printf("Disk image '%s' is encrypted.\n", filename);

        if (read_password(password, sizeof(password)) < 0) {

            error_report("No password given");

            goto fail;

        }

        if (bdrv_set_key(bs, password) < 0) {

            error_report("invalid password");

            goto fail;

        }

    }

    return bs;

fail:

    if (bs) {

        bdrv_delete(bs);

    }

    return NULL;

}

static int add_old_style_options(const char *fmt, QEMUOptionParameter *list,

                                 const char *base_filename,

                                 const char *base_fmt)

{

    if (base_filename) {

        if (set_option_parameter(list, BLOCK_OPT_BACKING_FILE, base_filename)) {

            error_report("Backing file not supported for file format '%s'",

                         fmt);

            return -1;

        }

    }

    if (base_fmt) {

        if (set_option_parameter(list, BLOCK_OPT_BACKING_FMT, base_fmt)) {

            error_report("Backing file format not supported for file "

                         "format '%s'", fmt);

            return -1;

        }

    }

    return 0;

}

static int img_create(int argc, char **argv)

{

    int c, ret = 0;

    uint64_t img_size = -1;

    const char *fmt = "raw";

    const char *base_fmt = NULL;

    const char *filename;

    const char *base_filename = NULL;

    char *options = NULL;

    for(;;) {

        c = getopt(argc, argv, "F:b:f:he6o:");

        if (c == -1) {

            break;

        }

        switch(c) {

        case '?':

        case 'h':

            help();

            break;

        case 'F':

            base_fmt = optarg;

            break;

        case 'b':

            base_filename = optarg;

            break;

        case 'f':

            fmt = optarg;

            break;

        case 'e':

            error_report("qemu-img: option -e is deprecated, please use \'-o "

                  "encryption\' instead!");

            return 1;

        case '6':

            error_report("qemu-img: option -6 is deprecated, please use \'-o "

                  "compat6\' instead!");

            return 1;

        case 'o':

            options = optarg;

            break;

        }

    }

    /* Get the filename */

    if (optind >= argc) {

        help();

    }

    filename = argv[optind++];

    /* Get image size, if specified */

    if (optind < argc) {

        ssize_t sval;

        sval = strtosz_suffix(argv[optind++], NULL, STRTOSZ_DEFSUFFIX_B);

        if (sval < 0) {

            error_report("Invalid image size specified! You may use k, M, G or "

                  "T suffixes for ");

            error_report("kilobytes, megabytes, gigabytes and terabytes.");

            ret = -1;

            goto out;

        }

        img_size = (uint64_t)sval;

    }

    if (options && !strcmp(options, "?")) {

        ret = print_block_option_help(filename, fmt);

        goto out;

    }

    ret = bdrv_img_create(filename, fmt, base_filename, base_fmt,

                          options, img_size, BDRV_O_FLAGS);

out:

    if (ret) {

        return 1;

    }

    return 0;

}

/*

 * Checks an image for consistency. Exit codes:

 *

 * 0 - Check completed, image is good

 * 1 - Check not completed because of internal errors

 * 2 - Check completed, image is corrupted

 * 3 - Check completed, image has leaked clusters, but is good otherwise

 */

static int img_check(int argc, char **argv)

{

    int c, ret;

    const char *filename, *fmt;

    BlockDriverState *bs;

    BdrvCheckResult result;

    fmt = NULL;

    for(;;) {

        c = getopt(argc, argv, "f:h");

        if (c == -1) {

            break;

        }

        switch(c) {

        case '?':

        case 'h':

            help();

            break;

        case 'f':

            fmt = optarg;

            break;

        }

    }

    if (optind >= argc) {

        help();

    }

    filename = argv[optind++];

    bs = bdrv_new_open(filename, fmt, BDRV_O_FLAGS);

    if (!bs) {

        return 1;

    }

    ret = bdrv_check(bs, &result);

    if (ret == -ENOTSUP) {

        error_report("This image format does not support checks");

        bdrv_delete(bs);

        return 1;

    }

    if (!(result.corruptions || result.leaks || result.check_errors)) {

        printf("No errors were found on the image.\n");

    } else {

        if (result.corruptions) {

            printf("\n%d errors were found on the image.\n"

                "Data may be corrupted, or further writes to the image "

                "may corrupt it.\n",

                result.corruptions);

        }

        if (result.leaks) {

            printf("\n%d leaked clusters were found on the image.\n"

                "This means waste of disk space, but no harm to data.\n",

                result.leaks);

        }

        if (result.check_errors) {

            printf("\n%d internal errors have occurred during the check.\n",

                result.check_errors);

        }

    }

    bdrv_delete(bs);

    if (ret < 0 || result.check_errors) {

        printf("\nAn error has occurred during the check: %s\n"

            "The check is not complete and may have missed error.\n",

            strerror(-ret));

        return 1;

    }

    if (result.corruptions) {

        return 2;

    } else if (result.leaks) {

        return 3;

    } else {

        return 0;

    }

}

static int img_commit(int argc, char **argv)

{

    int c, ret;

    const char *filename, *fmt;

    BlockDriverState *bs;

    fmt = NULL;

    for(;;) {

        c = getopt(argc, argv, "f:h");

        if (c == -1) {

            break;

        }

        switch(c) {

        case '?':

        case 'h':

            help();

            break;

        case 'f':

            fmt = optarg;

            break;

        }

    }

    if (optind >= argc) {

        help();

    }

    filename = argv[optind++];

    bs = bdrv_new_open(filename, fmt, BDRV_O_FLAGS | BDRV_O_RDWR);

    if (!bs) {

        return 1;

    }

    ret = bdrv_commit(bs);

    switch(ret) {

    case 0:

        printf("Image committed.\n");

        break;

    case -ENOENT:

        error_report("No disk inserted");

        break;

    case -EACCES:

        error_report("Image is read-only");

        break;

    case -ENOTSUP:

        error_report("Image is already committed");

        break;

    default:

        error_report("Error while committing image");

        break;

    }

    bdrv_delete(bs);

    if (ret) {

        return 1;

    }

    return 0;

}

static int is_not_zero(const uint8_t *sector, int len)

{

    int i;

    len >>= 2;

    for(i = 0;i < len; i++) {

        if (((uint32_t *)sector)[i] != 0)

            return 1;

    }

    return 0;

}

/*

 * Returns true iff the first sector pointed to by 'buf' contains at least

 * a non-NUL byte.

 *

 * 'pnum' is set to the number of sectors (including and immediately following

 * the first one) that are known to be in the same allocated/unallocated state.

 */

static int is_allocated_sectors(const uint8_t *buf, int n, int *pnum)

{

    int v, i;

    if (n <= 0) {

        *pnum = 0;

        return 0;

    }

    v = is_not_zero(buf, 512);

    for(i = 1; i < n; i++) {

        buf += 512;

        if (v != is_not_zero(buf, 512))

            break;

    }

    *pnum = i;

    return v;

}

/*

 * Compares two buffers sector by sector. Returns 0 if the first sector of both

 * buffers matches, non-zero otherwise.

 *

 * pnum is set to the number of sectors (including and immediately following

 * the first one) that are known to have the same comparison result

 */

static int compare_sectors(const uint8_t *buf1, const uint8_t *buf2, int n,

    int *pnum)

{

    int res, i;

    if (n <= 0) {

        *pnum = 0;

        return 0;

    }

    res = !!memcmp(buf1, buf2, 512);

    for(i = 1; i < n; i++) {

        buf1 += 512;

        buf2 += 512;

        if (!!memcmp(buf1, buf2, 512) != res) {

            break;

        }

    }

    *pnum = i;

    return res;

}

#define IO_BUF_SIZE (2 * 1024 * 1024)

static int img_convert(int argc, char **argv)

{

    int c, ret = 0, n, n1, bs_n, bs_i, compress, cluster_size, cluster_sectors;

    const char *fmt, *out_fmt, *out_baseimg, *out_filename;

    BlockDriver *drv, *proto_drv;

    BlockDriverState **bs = NULL, *out_bs = NULL;

    int64_t total_sectors, nb_sectors, sector_num, bs_offset;

    uint64_t bs_sectors;

    uint8_t * buf = NULL;

    const uint8_t *buf1;

    BlockDriverInfo bdi;

    QEMUOptionParameter *param = NULL, *create_options = NULL;

    QEMUOptionParameter *out_baseimg_param;

    char *options = NULL;

    const char *snapshot_name = NULL;

    fmt = NULL;

    out_fmt = "raw";

    out_baseimg = NULL;

    compress = 0;

    for(;;) {

        c = getopt(argc, argv, "f:O:B:s:hce6o:");

        if (c == -1) {

            break;

        }

        switch(c) {

        case '?':

        case 'h':

            help();

            break;

        case 'f':

            fmt = optarg;

            break;

        case 'O':

            out_fmt = optarg;

            break;

        case 'B':

            out_baseimg = optarg;

            break;

        case 'c':

            compress = 1;

            break;

        case 'e':

            error_report("qemu-img: option -e is deprecated, please use \'-o "

                  "encryption\' instead!");

            return 1;

        case '6':

            error_report("qemu-img: option -6 is deprecated, please use \'-o "

                  "compat6\' instead!");

            return 1;

        case 'o':

            options = optarg;

            break;

        case 's':

            snapshot_name = optarg;

            break;

        }

    }

    bs_n = argc - optind - 1;

    if (bs_n < 1) {

        help();

    }

    out_filename = argv[argc - 1];

    if (options && !strcmp(options, "?")) {

        ret = print_block_option_help(out_filename, out_fmt);

        goto out;

    }

    if (bs_n > 1 && out_baseimg) {

        error_report("-B makes no sense when concatenating multiple input "

                     "images");

        ret = -1;

        goto out;

    }

    bs = qemu_mallocz(bs_n * sizeof(BlockDriverState *));

    total_sectors = 0;

    for (bs_i = 0; bs_i < bs_n; bs_i++) {

        bs[bs_i] = bdrv_new_open(argv[optind + bs_i], fmt, BDRV_O_FLAGS);

        if (!bs[bs_i]) {

            error_report("Could not open '%s'", argv[optind + bs_i]);

            ret = -1;

            goto out;

        }

        bdrv_get_geometry(bs[bs_i], &bs_sectors);

        total_sectors += bs_sectors;

    }

    if (snapshot_name != NULL) {

        if (bs_n > 1) {

            error_report("No support for concatenating multiple snapshot\n");

            ret = -1;

            goto out;

        }

        if (bdrv_snapshot_load_tmp(bs[0], snapshot_name) < 0) {

            error_report("Failed to load snapshot\n");

            ret = -1;

            goto out;

        }

    }

    /* Find driver and parse its options */

    drv = bdrv_find_format(out_fmt);

    if (!drv) {

        error_report("Unknown file format '%s'", out_fmt);

        ret = -1;

        goto out;

    }

    proto_drv = bdrv_find_protocol(out_filename);

    if (!proto_drv) {

        error_report("Unknown protocol '%s'", out_filename);

        ret = -1;

        goto out;

    }

    create_options = append_option_parameters(create_options,

                                              drv->create_options);

    create_options = append_option_parameters(create_options,

                                              proto_drv->create_options);

    if (options) {

        param = parse_option_parameters(options, create_options, param);

        if (param == NULL) {

            error_report("Invalid options for file format '%s'.", out_fmt);

            ret = -1;

            goto out;

        }

    } else {

        param = parse_option_parameters("", create_options, param);

    }

    set_option_parameter_int(param, BLOCK_OPT_SIZE, total_sectors * 512);

    ret = add_old_style_options(out_fmt, param, out_baseimg, NULL);

    if (ret < 0) {

        goto out;

    }

    /* Get backing file name if -o backing_file was used */

    out_baseimg_param = get_option_parameter(param, BLOCK_OPT_BACKING_FILE);

    if (out_baseimg_param) {

        out_baseimg = out_baseimg_param->value.s;

    }

    /* Check if compression is supported */

    if (compress) {

        QEMUOptionParameter *encryption =

            get_option_parameter(param, BLOCK_OPT_ENCRYPT);

        if (!drv->bdrv_write_compressed) {

            error_report("Compression not supported for this file format");

            ret = -1;

            goto out;

        }

        if (encryption && encryption->value.n) {

            error_report("Compression and encryption not supported at "

                         "the same time");

            ret = -1;

            goto out;

        }

    }

    /* Create the new image */

    ret = bdrv_create(drv, out_filename, param);

    if (ret < 0) {

        if (ret == -ENOTSUP) {

            error_report("Formatting not supported for file format '%s'",

                         out_fmt);

        } else if (ret == -EFBIG) {

            error_report("The image size is too large for file format '%s'",

                         out_fmt);

        } else {

            error_report("%s: error while converting %s: %s",

                         out_filename, out_fmt, strerror(-ret));

        }

        goto out;

    }

    out_bs = bdrv_new_open(out_filename, out_fmt,

        BDRV_O_FLAGS | BDRV_O_RDWR | BDRV_O_NO_FLUSH);

    if (!out_bs) {

        ret = -1;

        goto out;

    }

    bs_i = 0;

    bs_offset = 0;

    bdrv_get_geometry(bs[0], &bs_sectors);

    buf = qemu_malloc(IO_BUF_SIZE);

    if (compress) {

        ret = bdrv_get_info(out_bs, &bdi);

        if (ret < 0) {

            error_report("could not get block driver info");

            goto out;

        }

        cluster_size = bdi.cluster_size;

        if (cluster_size <= 0 || cluster_size > IO_BUF_SIZE) {

            error_report("invalid cluster size");

            ret = -1;

            goto out;

        }

        cluster_sectors = cluster_size >> 9;

        sector_num = 0;

        for(;;) {

            int64_t bs_num;

            int remainder;

            uint8_t *buf2;

            nb_sectors = total_sectors - sector_num;

            if (nb_sectors <= 0)

                break;

            if (nb_sectors >= cluster_sectors)

                n = cluster_sectors;

            else

                n = nb_sectors;

            bs_num = sector_num - bs_offset;

            assert (bs_num >= 0);

            remainder = n;

            buf2 = buf;

            while (remainder > 0) {

                int nlow;

                while (bs_num == bs_sectors) {

                    bs_i++;

                    assert (bs_i < bs_n);

                    bs_offset += bs_sectors;

                    bdrv_get_geometry(bs[bs_i], &bs_sectors);

                    bs_num = 0;

                    /* printf("changing part: sector_num=%" PRId64 ", "

                       "bs_i=%d, bs_offset=%" PRId64 ", bs_sectors=%" PRId64

                       "\n", sector_num, bs_i, bs_offset, bs_sectors); */

                }

                assert (bs_num < bs_sectors);

                nlow = (remainder > bs_sectors - bs_num) ? bs_sectors - bs_num : remainder;

                ret = bdrv_read(bs[bs_i], bs_num, buf2, nlow);

                if (ret < 0) {

                    error_report("error while reading");

                    goto out;

                }

                buf2 += nlow * 512;

                bs_num += nlow;

                remainder -= nlow;

            }

            assert (remainder == 0);

            if (n < cluster_sectors) {

                memset(buf + n * 512, 0, cluster_size - n * 512);

            }

            if (is_not_zero(buf, cluster_size)) {

                ret = bdrv_write_compressed(out_bs, sector_num, buf,

                                            cluster_sectors);

                if (ret != 0) {

                    error_report("error while compressing sector %" PRId64,

                          sector_num);

                    goto out;

                }

            }

            sector_num += n;

        }

        /* signal EOF to align */

        bdrv_write_compressed(out_bs, 0, NULL, 0);

    } else {

        int has_zero_init = bdrv_has_zero_init(out_bs);

        sector_num = 0; // total number of sectors converted so far

        for(;;) {

            nb_sectors = total_sectors - sector_num;

            if (nb_sectors <= 0) {

                break;

            }

            if (nb_sectors >= (IO_BUF_SIZE / 512)) {

                n = (IO_BUF_SIZE / 512);

            } else {

                n = nb_sectors;

            }

            while (sector_num - bs_offset >= bs_sectors) {

                bs_i ++;

                assert (bs_i < bs_n);

                bs_offset += bs_sectors;

                bdrv_get_geometry(bs[bs_i], &bs_sectors);

                /* printf("changing part: sector_num=%" PRId64 ", bs_i=%d, "

                  "bs_offset=%" PRId64 ", bs_sectors=%" PRId64 "\n",

                   sector_num, bs_i, bs_offset, bs_sectors); */

            }

            if (n > bs_offset + bs_sectors - sector_num) {

                n = bs_offset + bs_sectors - sector_num;

            }

            if (has_zero_init) {

                /* If the output image is being created as a copy on write image,

                   assume that sectors which are unallocated in the input image

                   are present in both the output's and input's base images (no

                   need to copy them). */

                if (out_baseimg) {

                    if (!bdrv_is_allocated(bs[bs_i], sector_num - bs_offset,

                                           n, &n1)) {

                        sector_num += n1;

                        continue;

                    }

                    /* The next 'n1' sectors are allocated in the input image. Copy

                       only those as they may be followed by unallocated sectors. */

                    n = n1;

                }

            } else {

                n1 = n;

            }

            ret = bdrv_read(bs[bs_i], sector_num - bs_offset, buf, n);

            if (ret < 0) {

                error_report("error while reading");

                goto out;

            }

            /* NOTE: at the same time we convert, we do not write zero

               sectors to have a chance to compress the image. Ideally, we

               should add a specific call to have the info to go faster */

            buf1 = buf;

            while (n > 0) {

                /* If the output image is being created as a copy on write image,

                   copy all sectors even the ones containing only NUL bytes,

                   because they may differ from the sectors in the base image.

                   If the output is to a host device, we also write out

                   sectors that are entirely 0, since whatever data was

                   already there is garbage, not 0s. */

                if (!has_zero_init || out_baseimg ||

                    is_allocated_sectors(buf1, n, &n1)) {

                    ret = bdrv_write(out_bs, sector_num, buf1, n1);

                    if (ret < 0) {

                        error_report("error while writing");

                        goto out;

                    }

                }

                sector_num += n1;

                n -= n1;

                buf1 += n1 * 512;

            }

        }

    }

out:

    free_option_parameters(create_options);

    free_option_parameters(param);

    qemu_free(buf);

    if (out_bs) {

        bdrv_delete(out_bs);

    }

    if (bs) {

        for (bs_i = 0; bs_i < bs_n; bs_i++) {

            if (bs[bs_i]) {

                bdrv_delete(bs[bs_i]);

            }

        }

        qemu_free(bs);

    }

    if (ret) {

        return 1;

    }

    return 0;

}

#ifdef _WIN32

static int64_t get_allocated_file_size(const char *filename)

{

    typedef DWORD (WINAPI * get_compressed_t)(const char *filename, DWORD *high);

    get_compressed_t get_compressed;

    struct _stati64 st;

    /* WinNT support GetCompressedFileSize to determine allocate size */

    get_compressed = (get_compressed_t) GetProcAddress(GetModuleHandle("kernel32"), "GetCompressedFileSizeA");

    if (get_compressed) {

            DWORD high, low;

            low = get_compressed(filename, &high);

            if (low != 0xFFFFFFFFlu || GetLastError() == NO_ERROR)

            return (((int64_t) high) << 32) + low;

    }

    if (_stati64(filename, &st) < 0)

        return -1;

    return st.st_size;

}

#else

static int64_t get_allocated_file_size(const char *filename)

{

    struct stat st;

    if (stat(filename, &st) < 0)

        return -1;

    return (int64_t)st.st_blocks * 512;

}

#endif

static void dump_snapshots(BlockDriverState *bs)

{

    QEMUSnapshotInfo *sn_tab, *sn;

    int nb_sns, i;

    char buf[256];

    nb_sns = bdrv_snapshot_list(bs, &sn_tab);

    if (nb_sns <= 0)

        return;

    printf("Snapshot list:\n");

    printf("%s\n", bdrv_snapshot_dump(buf, sizeof(buf), NULL));

    for(i = 0; i < nb_sns; i++) {

        sn = &sn_tab[i];

        printf("%s\n", bdrv_snapshot_dump(buf, sizeof(buf), sn));

    }

    qemu_free(sn_tab);

}

static int img_info(int argc, char **argv)

{

    int c;

    const char *filename, *fmt;

    BlockDriverState *bs;

    char fmt_name[128], size_buf[128], dsize_buf[128];

    uint64_t total_sectors;

    int64_t allocated_size;

    char backing_filename[1024];

    char backing_filename2[1024];

    BlockDriverInfo bdi;

    fmt = NULL;

    for(;;) {

        c = getopt(argc, argv, "f:h");

        if (c == -1) {

            break;

        }

        switch(c) {

        case '?':

        case 'h':

            help();

            break;

        case 'f':

            fmt = optarg;

            break;

        }

    }

    if (optind >= argc) {

        help();

    }

    filename = argv[optind++];

    bs = bdrv_new_open(filename, fmt, BDRV_O_FLAGS | BDRV_O_NO_BACKING);

    if (!bs) {

        return 1;

    }

    bdrv_get_format(bs, fmt_name, sizeof(fmt_name));

    bdrv_get_geometry(bs, &total_sectors);

    get_human_readable_size(size_buf, sizeof(size_buf), total_sectors * 512);

    allocated_size = get_allocated_file_size(filename);

    if (allocated_size < 0) {

        snprintf(dsize_buf, sizeof(dsize_buf), "unavailable");

    } else {

        get_human_readable_size(dsize_buf, sizeof(dsize_buf),

                                allocated_size);

    }

    printf("image: %s\n"

           "file format: %s\n"

           "virtual size: %s (%" PRId64 " bytes)\n"

           "disk size: %s\n",

           filename, fmt_name, size_buf,

           (total_sectors * 512),

           dsize_buf);

    if (bdrv_is_encrypted(bs)) {

        printf("encrypted: yes\n");

    }

    if (bdrv_get_info(bs, &bdi) >= 0) {

        if (bdi.cluster_size != 0) {

            printf("cluster_size: %d\n", bdi.cluster_size);

        }

    }

    bdrv_get_backing_filename(bs, backing_filename, sizeof(backing_filename));

    if (backing_filename[0] != '\0') {

        path_combine(backing_filename2, sizeof(backing_filename2),

                     filename, backing_filename);

        printf("backing file: %s (actual path: %s)\n",

               backing_filename,

               backing_filename2);

    }

    dump_snapshots(bs);

    bdrv_delete(bs);

    return 0;

}

#define SNAPSHOT_LIST   1

#define SNAPSHOT_CREATE 2

#define SNAPSHOT_APPLY  3

#define SNAPSHOT_DELETE 4

static int img_snapshot(int argc, char **argv)

{

    BlockDriverState *bs;

    QEMUSnapshotInfo sn;

    char *filename, *snapshot_name = NULL;

    int c, ret = 0, bdrv_oflags;

    int action = 0;

    qemu_timeval tv;

    bdrv_oflags = BDRV_O_RDWR;

    /* Parse commandline parameters */

    for(;;) {

        c = getopt(argc, argv, "la:c:d:h");

        if (c == -1) {

            break;

        }

        switch(c) {

        case '?':

        case 'h':

            help();

            return 0;

        case 'l':

            if (action) {

                help();

                return 0;

            }

            action = SNAPSHOT_LIST;

            bdrv_oflags &= ~BDRV_O_RDWR; /* no need for RW */

            break;

        case 'a':

            if (action) {

                help();

                return 0;

            }

            action = SNAPSHOT_APPLY;

            snapshot_name = optarg;

            break;

        case 'c':

            if (action) {

                help();

                return 0;

            }

            action = SNAPSHOT_CREATE;

            snapshot_name = optarg;

            break;

        case 'd':

            if (action) {

                help();

                return 0;

            }

            action = SNAPSHOT_DELETE;

            snapshot_name = optarg;

            break;

        }

    }

    if (optind >= argc) {

        help();

    }

    filename = argv[optind++];

    /* Open the image */

    bs = bdrv_new_open(filename, NULL, bdrv_oflags);

    if (!bs) {

        return 1;

    }

    /* Perform the requested action */

    switch(action) {

    case SNAPSHOT_LIST:

        dump_snapshots(bs);

        break;

    case SNAPSHOT_CREATE:

        memset(&sn, 0, sizeof(sn));

        pstrcpy(sn.name, sizeof(sn.name), snapshot_name);

        qemu_gettimeofday(&tv);

        sn.date_sec = tv.tv_sec;

        sn.date_nsec = tv.tv_usec * 1000;

        ret = bdrv_snapshot_create(bs, &sn);

        if (ret) {

            error_report("Could not create snapshot '%s': %d (%s)",

                snapshot_name, ret, strerror(-ret));

        }

        break;

    case SNAPSHOT_APPLY:

        ret = bdrv_snapshot_goto(bs, snapshot_name);

        if (ret) {

            error_report("Could not apply snapshot '%s': %d (%s)",

                snapshot_name, ret, strerror(-ret));

        }

        break;

    case SNAPSHOT_DELETE:

        ret = bdrv_snapshot_delete(bs, snapshot_name);

        if (ret) {

            error_report("Could not delete snapshot '%s': %d (%s)",

                snapshot_name, ret, strerror(-ret));

        }

        break;

    }

    /* Cleanup */

    bdrv_delete(bs);

    if (ret) {

        return 1;

    }

    return 0;

}

static int img_rebase(int argc, char **argv)

{

    BlockDriverState *bs, *bs_old_backing = NULL, *bs_new_backing = NULL;

    BlockDriver *old_backing_drv, *new_backing_drv;

    char *filename;

    const char *fmt, *out_basefmt, *out_baseimg;

    int c, flags, ret;

    int unsafe = 0;

    /* Parse commandline parameters */

    fmt = NULL;

    out_baseimg = NULL;

    out_basefmt = NULL;

    for(;;) {

        c = getopt(argc, argv, "uhf:F:b:");

        if (c == -1) {

            break;

        }

        switch(c) {

        case '?':

        case 'h':

            help();

            return 0;

        case 'f':

            fmt = optarg;

            break;

        case 'F':

            out_basefmt = optarg;

            break;

        case 'b':

            out_baseimg = optarg;

            break;

        case 'u':

            unsafe = 1;

            break;

        }

    }

    if ((optind >= argc) || !out_baseimg) {

        help();

    }

    filename = argv[optind++];

    /*

     * Open the images.

     *

     * Ignore the old backing file for unsafe rebase in case we want to correct

     * the reference to a renamed or moved backing file.

     */

    flags = BDRV_O_FLAGS | BDRV_O_RDWR | (unsafe ? BDRV_O_NO_BACKING : 0);

    bs = bdrv_new_open(filename, fmt, flags);

    if (!bs) {

        return 1;

    }

    /* Find the right drivers for the backing files */

    old_backing_drv = NULL;

    new_backing_drv = NULL;

    if (!unsafe && bs->backing_format[0] != '\0') {

        old_backing_drv = bdrv_find_format(bs->backing_format);

        if (old_backing_drv == NULL) {

            error_report("Invalid format name: '%s'", bs->backing_format);

            ret = -1;

            goto out;

        }

    }

    if (out_basefmt != NULL) {

        new_backing_drv = bdrv_find_format(out_basefmt);

        if (new_backing_drv == NULL) {

            error_report("Invalid format name: '%s'", out_basefmt);

            ret = -1;

            goto out;

        }

    }

    /* For safe rebasing we need to compare old and new backing file */

    if (unsafe) {

        /* Make the compiler happy */

        bs_old_backing = NULL;

        bs_new_backing = NULL;

    } else {

        char backing_name[1024];

        bs_old_backing = bdrv_new("old_backing");

        bdrv_get_backing_filename(bs, backing_name, sizeof(backing_name));

        ret = bdrv_open(bs_old_backing, backing_name, BDRV_O_FLAGS,

                        old_backing_drv);

        if (ret) {

            error_report("Could not open old backing file '%s'", backing_name);

            goto out;

        }

        bs_new_backing = bdrv_new("new_backing");

        ret = bdrv_open(bs_new_backing, out_baseimg, BDRV_O_FLAGS,

                        new_backing_drv);

        if (ret) {

            error_report("Could not open new backing file '%s'", out_baseimg);

            goto out;

        }

    }

    /*

     * Check each unallocated cluster in the COW file. If it is unallocated,

     * accesses go to the backing file. We must therefore compare this cluster

     * in the old and new backing file, and if they differ we need to copy it

     * from the old backing file into the COW file.