Re: [Qemu-devel] [PATCH] qemu-io: New command map

[Stefan Hajnoczi]

On Tue, Sep 21, 2010 at 12:01 PM, Kevin Wolf <address@hidden> wrote:
> The new map command in qemu-io lists all allocated/unallocated areas in an
> image file.
>
> Signed-off-by: Kevin Wolf <address@hidden>
> ---
>  qemu-io.c |   38 ++++++++++++++++++++++++++++++++++++++
>  1 files changed, 38 insertions(+), 0 deletions(-)
>
> diff --git a/qemu-io.c b/qemu-io.c
> index b4e5cc8..169dd51 100644
> --- a/qemu-io.c
> +++ b/qemu-io.c
> @@ -1443,6 +1443,43 @@ static const cmdinfo_t alloc_cmd = {
>  };
>
>  static int
> +map_f(int argc, char **argv)
> +{
> +       int64_t offset;
> +       int nb_sectors;
> +       char s1[64];
> +       int num;
> +       int ret;
> +       const char *retstr;
> +
> +       offset = 0;
> +       nb_sectors = bs->total_sectors;

total_sectors is int64_t but nb_sectors is int.  A >1 TB image with
will have nb_sectors > 0x80000000.  The safest solution is to use
int64_t and cap the nb_sectors argument at INT_MAX per iteration.

Stefan