Re: [pmg-devel] [PATCH log-tracker 1/2] add support for bookworm syslog time format

[Dominik Csapak <d.csapak@proxmox.com>]

One nit inline, but aside from that consider these two patches:

Reviewed-by: Dominik Csapak <d.csapak@proxmox.com>
Tested-by: Dominik Csapak <d.csapak@proxmox.com>

On 6/26/23 12:41, Mira Limbeck wrote:
> Adds `proxmox-time` as dependency to parse the timestamp
> 
> Since parse_rfc3339 can't handle microseconds, we try to remove the dot
> followed by 6 digits of microseconds before passing it to parse_rfc3339.
> 
> A fallback to the previous format is used when when it fails to parse
> the new format.
> 
> Signed-off-by: Mira Limbeck <m.limbeck@proxmox.com>
> ---
>   Cargo.toml  |  1 +
>   src/main.rs | 36 ++++++++++++++++++++++++++++++++++++
>   2 files changed, 37 insertions(+)
> 
> diff --git a/Cargo.toml b/Cargo.toml
> index b484137..6d92253 100644
> --- a/Cargo.toml
> +++ b/Cargo.toml
> @@ -14,3 +14,4 @@ anyhow = "1"
>   clap = { version = "3.2.23", features = ["cargo"] }
>   flate2 = "1.0"
>   libc = "0.2"
> +proxmox-time = "1.1"
> diff --git a/src/main.rs b/src/main.rs
> index 20d8404..e7bffd8 100644
> --- a/src/main.rs
> +++ b/src/main.rs
> @@ -2236,6 +2236,42 @@ fn parse_number(data: &[u8], max_digits: usize) -> Option<(usize, &[u8])> {
>   
>   /// Parse time. Returns a tuple of (parsed_time, remaining_text) or None.
>   fn parse_time(data: &'_ [u8], cur_year: i64, cur_month: i64) -> Option<(time_t, &'_ [u8])> {
> +    parse_time_with_year(data).or_else(|| parse_time_no_year(data, cur_year, cur_month))
> +}
> +
> +fn parse_time_with_year(data: &'_ [u8]) -> Option<(time_t, &'_ [u8])> {
> +    let mut timestamp_buffer = [0u8; 25];
> +
> +    let count = data.iter().take_while(|b| **b != b' ').count();

nit: wouldn't also a '.position(" ")' work?
could be a bit faster, since rust would not have to create another iterator?
(or maybe rust is smart enough to compile it out anyway?)

> +    if count != 27 && count != 32 {
> +        return None;
> +    }
> +    let (timestamp, data) = data.split_at(count);
> +    // remove whitespace
> +    let data = &data[1..];
> +
> +    // microseconds: .123456 -> 7 bytes
> +    let microseconds_idx = timestamp.iter().take_while(|b| **b != b'.').count();
> +
> +    // YYYY-MM-DDTHH:MM:SS
> +    let year_time = &timestamp[0..microseconds_idx];
> +    let year_time_len = year_time.len();
> +    // Z | +HH:MM | -HH:MM
> +    let timezone = &timestamp[microseconds_idx + 7..];
> +    let timezone_len = timezone.len();
> +    let timestamp_len = year_time_len + timezone_len;
> +    timestamp_buffer[0..year_time_len].copy_from_slice(year_time);
> +    timestamp_buffer[year_time_len..timestamp_len].copy_from_slice(timezone);
> +
> +    match proxmox_time::parse_rfc3339(unsafe {
> +        std::str::from_utf8_unchecked(&timestamp_buffer[0..timestamp_len])
> +    }) {
> +        Ok(ltime) => Some((ltime, data)),
> +        Err(_err) => None,
> +    }
> +}
> +
> +fn parse_time_no_year(data: &'_ [u8], cur_year: i64, cur_month: i64) -> Option<(time_t, &'_ [u8])> {
>       if data.len() < 15 {
>           return None;
>       }