public inbox for pbs-devel@lists.proxmox.com
 help / color / mirror / Atom feed
From: Wolfgang Bumiller <w.bumiller@proxmox.com>
To: Gabriel Goller <g.goller@proxmox.com>
Cc: pbs-devel@lists.proxmox.com
Subject: Re: [pbs-devel] [PATCH proxmox-backup v3] client: mount: wait for child to return before exiting
Date: Tue, 18 Jun 2024 15:44:47 +0200	[thread overview]
Message-ID: <lzfzyjzp73cyknbado5ompdgiokbexdkbbp6dgnyb7vkbsilfo@exije6apc43f> (raw)
In-Reply-To: <20240618133558.290048-1-g.goller@proxmox.com>

On Tue, Jun 18, 2024 at 03:35:56PM GMT, Gabriel Goller wrote:
> When using the `proxmox-backup-client mount` command, the parent sometimes
> exits before we can print any error message. Most notably this happens
> when no PBS_REPOSITORY is passed, as this is the first option checked.
> If the underlying file descriptor has been closed, wait for the client
> to complete and return the error message.
> 
> Reported-by: Friedrich Weber <f.weber@proxmox.com>
> Suggested-by: Christian Ebner <c.ebner@proxmox.com>
> Signed-off-by: Gabriel Goller <g.goller@proxmox.com>
> ---
> 
> v3, thanks @Christian, @Friedrich:
>  - Removed stdout/stderr flush (which didn't solve the problem)
>  - Wait for child to finish
> 
> v2, thanks @Christian:
>  - Removed unneeded pw.try_clone()
> 
>  proxmox-backup-client/src/mount.rs | 14 ++++++++++++--
>  1 file changed, 12 insertions(+), 2 deletions(-)
> 
> diff --git a/proxmox-backup-client/src/mount.rs b/proxmox-backup-client/src/mount.rs
> index b69e7e80..966ea1f9 100644
> --- a/proxmox-backup-client/src/mount.rs
> +++ b/proxmox-backup-client/src/mount.rs
> @@ -183,7 +183,17 @@ fn mount(
>          Ok(ForkResult::Parent { .. }) => {
>              drop(pw);
>              // Blocks the parent process until we are ready to go in the child
> -            let _res = nix::unistd::read(pr.as_raw_fd(), &mut [0]).unwrap();
> +            let mut buffer: Vec<u8> = vec![0];

No need to use a `Vec` here, just use `let mut buffer = [0u8];`

> +            nix::unistd::read(pr.as_raw_fd(), &mut buffer).unwrap();
> +
> +            // Read buffer didn't change, which indicates that nothing has been read and the file
> +            // descriptor has probably been closed. This means that there was an error in the child
> +            // process and it did not daemonize correctly.
> +            if buffer[0] == 0 {
> +                // Wait for the child process to finish, so it can return a nice error.
> +                nix::sys::wait::wait().unwrap();
> +            }
> +
>              Ok(Value::Null)
>          }
>          Ok(ForkResult::Child) => {
> @@ -264,7 +274,7 @@ async fn mount_do(param: Value, pipe: Option<OwnedFd>) -> Result<Value, Error> {
>              }
>              // Signal the parent process that we are done with the setup and it can
>              // terminate.
> -            nix::unistd::write(pipe.as_raw_fd(), &[0u8])?;
> +            nix::unistd::write(pipe.as_raw_fd(), &[1u8])?;
>              let _: OwnedFd = pipe;
>          }
>  
> -- 
> 2.43.0


_______________________________________________
pbs-devel mailing list
pbs-devel@lists.proxmox.com
https://lists.proxmox.com/cgi-bin/mailman/listinfo/pbs-devel


  reply	other threads:[~2024-06-18 13:45 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-06-18 13:35 Gabriel Goller
2024-06-18 13:44 ` Wolfgang Bumiller [this message]
2024-06-18 14:03   ` Gabriel Goller

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=lzfzyjzp73cyknbado5ompdgiokbexdkbbp6dgnyb7vkbsilfo@exije6apc43f \
    --to=w.bumiller@proxmox.com \
    --cc=g.goller@proxmox.com \
    --cc=pbs-devel@lists.proxmox.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
Service provided by Proxmox Server Solutions GmbH | Privacy | Legal