[Libguestfs] [PATCH 1/2] New API: list_md_devices

[Richard W.M. Jones]

On Thu, Nov 10, 2011 at 02:19:11PM +0000, Matthew Booth wrote:
> +    /* Look for directories under /sys/block matching md[0-9]*
> +     * As an additional check, we also make sure they have a md subdirectory */
> +    int err = glob(PREFIX "[0-9]*" SUFFIX, GLOB_ERR, NULL, &mds);
> +    if (err == GLOB_NOSPACE) {
> +        reply_with_error("OOM searching for md devices");
> +        goto error;
> +    } else if (err == GLOB_ABORTED) {
> +        reply_with_error("Read error searching for md devices");
> +        goto error;

Since glob is supposed to set errno on error, I'd prefer:

  reply_with_perror ("glob");

for both of the branches above (combine them into a single branch
if you like).

> +    } else if (err == GLOB_NOMATCH) {
> +        /* This is fine */
> +    }

I think this branch should just be dropped.

> +    for (size_t i = 0; i < mds.gl_pathc; i++) {
> +        size_t len = strlen(mds.gl_pathv[i]) - strlen(PREFIX) - strlen(SUFFIX);
> +
> +#define DEV "/dev/md"
> +        char *dev = malloc(strlen(DEV) + len  + 1);

Need to check the return value from malloc and reply_with_perror /
goto error on failure.

> +# Create a raid1 based on the 2 disks
> +debug sh "/usr/bin/yes | mdadm -C /dev/md/test --level=1 --raid-devices=2 /dev/vda /dev/vdb >/dev/null 2>&1"

I guessed we'd be running the debug backdoor here to create devices.
Is it not worth binding this call too?

> +# Ensure list-md-devices now returns the newly create md device

"created"

Generally looking good.

Rich.

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