[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH 3/3] qemu-nbd: Improve error reporting
From: |
Aurelien Jarno |
Subject: |
Re: [Qemu-devel] [PATCH 3/3] qemu-nbd: Improve error reporting |
Date: |
Sat, 27 Mar 2010 14:02:23 +0100 |
User-agent: |
Mutt/1.5.20 (2009-06-14) |
On Sat, Mar 20, 2010 at 03:23:24PM +0900, Ryota Ozaki wrote:
> - use err(3) instead of errx(3) if errno is available
> to report why failed
> - let fail prior to daemon(3) if opening a nbd file
> is likely to fail after daemonizing to avoid silent
> failure exit
>
> Signed-off-by: Ryota Ozaki <address@hidden>
> ---
> qemu-nbd.c | 16 +++++++++++-----
> 1 files changed, 11 insertions(+), 5 deletions(-)
>
> diff --git a/qemu-nbd.c b/qemu-nbd.c
> index 6d854d3..8fb8cc3 100644
> --- a/qemu-nbd.c
> +++ b/qemu-nbd.c
> @@ -316,7 +316,7 @@ int main(int argc, char **argv)
> if (disconnect) {
> fd = open(argv[optind], O_RDWR);
> if (fd == -1)
> - errx(EXIT_FAILURE, "Cannot open %s", argv[optind]);
> + err(EXIT_FAILURE, "Cannot open %s", argv[optind]);
>
> nbd_disconnect(fd);
>
> @@ -333,23 +333,29 @@ int main(int argc, char **argv)
> if (bs == NULL)
> return 1;
>
> - if (bdrv_open(bs, argv[optind], flags) < 0)
> - return 1;
> + if ((ret = bdrv_open(bs, argv[optind], flags)) < 0) {
> + errno = -ret;
> + err(EXIT_FAILURE, "Failed to bdrv_open '%s'", argv[optind]);
> + }
>
> fd_size = bs->total_sectors * 512;
>
> if (partition != -1 &&
> find_partition(bs, partition, &dev_offset, &fd_size))
> - errx(EXIT_FAILURE, "Could not find partition %d", partition);
> + err(EXIT_FAILURE, "Could not find partition %d", partition);
>
> if (device) {
> pid_t pid;
> int sock;
>
> + /* want to fail before daemonizing */
> + if (access(device, R_OK|W_OK) == -1)
> + err(EXIT_FAILURE, "Could not access '%s'", device);
> +
First of all you need to put this line between curly braces. Secondly,
qemu-nbd as a read-only option to export a block device as read-only.
The test has to be improved to also take care of that.
> if (!verbose) {
> /* detach client and server */
> if (daemon(0, 0) == -1) {
> - errx(EXIT_FAILURE, "Failed to daemonize");
> + err(EXIT_FAILURE, "Failed to daemonize");
> }
> }
>
> --
> 1.6.5.2
>
>
>
>
--
Aurelien Jarno GPG: 1024D/F1BCDB73
address@hidden http://www.aurel32.net