Re: [pbs-devel] [RFC pxar 7/20] fix #3174: encoder: add helper to incr encoder pos

[Wolfgang Bumiller <w.bumiller@proxmox.com>]

'incr' :S

On Fri, Sep 22, 2023 at 09:16:08AM +0200, Christian Ebner wrote:
> Adds a helper to allow to increase the encoder position by a given
> size. This is used to increase the position when adding an appendix
> section to the pxar stream, as these bytes are never encoded directly
> but rather referenced by already existing chunks.

Exposing this seems like a weird choice to me. Why exactly is this
needed? Why don't we instead expose methods to actually write the
appendix section instead?

> 
> Signed-off-by: Christian Ebner <c.ebner@proxmox.com>
> ---
>  src/encoder/aio.rs  | 5 +++++
>  src/encoder/mod.rs  | 6 ++++++
>  src/encoder/sync.rs | 5 +++++
>  3 files changed, 16 insertions(+)
> 
> diff --git a/src/encoder/aio.rs b/src/encoder/aio.rs
> index 3b6c900..3587f65 100644
> --- a/src/encoder/aio.rs
> +++ b/src/encoder/aio.rs
> @@ -112,6 +112,11 @@ impl<'a, T: SeqWrite + 'a> Encoder<'a, T> {
>          self.inner.finish().await
>      }
>  
> +    /// Add size to encoders position and return new position.
> +    pub fn position_add(&mut self, size: u64) -> u64 {
> +        self.inner.position_add(size)
> +    }
> +
>      /// Add reference to archive appendix
>      pub async fn add_appendix_ref<PF: AsRef<Path>>(
>          &mut self,
> diff --git a/src/encoder/mod.rs b/src/encoder/mod.rs
> index a513ce6..abe21f2 100644
> --- a/src/encoder/mod.rs
> +++ b/src/encoder/mod.rs
> @@ -626,6 +626,12 @@ impl<'a, T: SeqWrite + 'a> EncoderImpl<'a, T> {
>          self.state.write_position
>      }
>  
> +    #[inline]
> +    pub fn position_add(&mut self, size: u64) -> u64 {
> +        self.state.write_position += size;
> +        self.state.write_position
> +    }
> +
>      pub async fn create_directory(
>          &mut self,
>          file_name: &Path,
> diff --git a/src/encoder/sync.rs b/src/encoder/sync.rs
> index 372ca12..b3d7c44 100644
> --- a/src/encoder/sync.rs
> +++ b/src/encoder/sync.rs
> @@ -110,6 +110,11 @@ impl<'a, T: SeqWrite + 'a> Encoder<'a, T> {
>          poll_result_once(self.inner.finish())
>      }
>  
> +    /// Add size to encoders position and return new position.
> +    pub fn position_add(&mut self, size: u64) -> u64 {
> +        self.inner.position_add(size)
> +    }
> +
>      /// Add reference to archive appendix
>      pub async fn add_appendix_ref<PF: AsRef<Path>>(
>          &mut self,
> -- 
> 2.39.2