On Mon, Aug 20, 2012 at 11:47 AM, Benoît Canet <benoit.ca...@gmail.com> wrote:
> Valid quorum resources look like:
> quorum:threshold/total:path/to/image_1: ... :path/to/image_total
>
> '\' can escape the ':' character.
>
> Signed-off-by: Benoit Canet <ben...@irqsave.net>
> ---
> block/quorum.c | 110
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 110 insertions(+)
>
> diff --git a/block/quorum.c b/block/quorum.c
> index 19a9a44..70e7216 100644
> --- a/block/quorum.c
> +++ b/block/quorum.c
> @@ -52,11 +52,121 @@ struct QuorumAIOCB {
> int vote_ret;
> };
>
> +/* Valid quorum resources look like
> + * quorum:threshold/total:path/to/image_1: ... :path/to/image_total
> + */
> +static int quorum_open(BlockDriverState *bs, const char *filename, int flags)
> +{
> + BDRVQuorumState *s = bs->opaque;
> + int i, j, len, ret = 0;
> + char *a, *b, *names;
> + bool escape;
> +
> + /* Parse the quorum: prefix */
> + if (strncmp(filename, "quorum:", strlen("quorum:"))) {
> + return -EINVAL;
> + }
> +
> + filename += strlen("quorum:");
> +
> + /* Get n */
Here's still 'n' instead of threshold.
> + errno = 0;
> + s->threshold = strtoul(filename, &a, 10);
> + if (*a != '/' || errno) {
> + return -EINVAL;
> + }
> + a++;
> +
> + /* Get m */
Also 'm' here.
> + errno = 0;
> + s->total = strtoul(a, &b, 10);
> + if (*b != ':' || errno) {
> + return -EINVAL;
> + }
> + b++;
> +
> + if (s->threshold < 1 || s->total < 2) {
> + return -EINVAL;
> + }
> +
> + if (s->threshold > s->total) {
> + return -EINVAL;
> + }
> +
> + s->bs = g_malloc0(sizeof(BlockDriverState *) * s->total);
> + /* Two allocations for all filenames: simpler to free */
> + s->filenames = g_malloc0(sizeof(char *) * s->total);
> + names = g_strdup(b);
> +
> + /* Get the filenames pointers */
> + escape = false;
> + s->filenames[0] = names;
> + len = strlen(names);
> + for (i = 0, j = 1; i < len && j < s->total; i++) {
> + if (!escape && names[i] == ':') {
> + names[i] = '\0';
> + s->filenames[j] = names + i + 1;
> + j++;
> + }
> +
> + escape = !escape && names[i] == '\\';
> + }
> +
> + if (j != s->total) {
> + ret = -EINVAL;
> + goto free_exit;
> + }
> +
> + /* Open files */
> + for (i = 0; i < s->total; i++) {
> + s->bs[i] = bdrv_new("");
> + ret = bdrv_open(s->bs[i], s->filenames[i], flags, NULL);
> + if (ret < 0) {
> + goto error_exit;
> + }
> + }
> +
> + goto exit;
> +
> +error_exit:
> + for (; i >= 0; i--) {
> + bdrv_delete(s->bs[i]);
> + s->bs[i] = NULL;
> + }
> +free_exit:
> + g_free(s->filenames[0]);
> + g_free(s->filenames);
> + s->filenames = NULL;
> + g_free(s->bs);
> +exit:
> + return ret;
> +}
> +
> +static void quorum_close(BlockDriverState *bs)
> +{
> + BDRVQuorumState *s = bs->opaque;
> + int i;
> +
> + for (i = 0; i < s->total; i++) {
> + /* Ensure writes reach stable storage */
> + bdrv_flush(s->bs[i]);
> + bdrv_delete(s->bs[i]);
> + }
> +
> + g_free(s->filenames[0]);
> + g_free(s->filenames);
> + s->filenames = NULL;
> + g_free(s->bs);
> +}
> +
> static BlockDriver bdrv_quorum = {
> .format_name = "quorum",
> .protocol_name = "quorum",
>
> .instance_size = sizeof(BDRVQuorumState),
> +
> + .bdrv_file_open = quorum_open,
> + .bdrv_close = quorum_close,
> };
>
> static void bdrv_quorum_init(void)
> --
> 1.7.9.5
>
