[Libguestfs] [PATCH 1/2] New API: btrfs-image

[Richard W.M. Jones]

On Tue, Mar 03, 2015 at 03:48:02AM -0500, Chen Hanxiao wrote:
> Signed-off-by: Chen Hanxiao <chenhanxiao at cn.fujitsu.com>
> +  if (compresslevel >= 0) {
> +    snprintf (compresslevel_s, sizeof compresslevel_s, "%d", compresslevel);
> +    ADD_ARG (argv, i, "-c");
> +    ADD_ARG (argv, i, compresslevel_s);
> +  }

Because compresslevel is an optional parameter, you can't just use it
directly like this.  You have to check optargs_bitmask.  The condition
should be something like:

  if ((optargs_bitmask & GUESTFS_BTRFS_IMAGE_COMPRESSLEVEL_BITMASK) &&
      compresslevel >= 0) {
    ...
  }

> +  if (numthreads) {

I would prefer not to expose the -t parameter, since it's essentially
an implementation detail.

If btrfs-image doesn't do the right thing, then you could pass
`sysconf (_SC_NPROCESSORS_ONLN)' here (see builder/pxzcat-c.c for an
example).

> +This used to create an image of a btrfs filesystem.

     ^ This is used ...

> +All data will be zeroed, but metadata and the like is preserved." };

This is fine with the corrections above.

Rich.

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