[pbs-devel] [PATCH proxmox-backup] rrd: use saturating_sub to avoid underflow

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

Without this, the tests fail in debug mode.
Also having start (u64) underflow to a value greater than end does
not really make sense

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
---
 proxmox-rrd/src/rrd.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/proxmox-rrd/src/rrd.rs b/proxmox-rrd/src/rrd.rs
index 20bf6ae3..2fab9df3 100644
--- a/proxmox-rrd/src/rrd.rs
+++ b/proxmox-rrd/src/rrd.rs
@@ -469,7 +469,7 @@ impl RRD {
         match rra {
             Some(rra) => {
                 let end = end.unwrap_or_else(|| proxmox_time::epoch_f64() as u64);
-                let start = start.unwrap_or(end - 10*rra.resolution);
+                let start = start.unwrap_or(end.saturating_sub(10*rra.resolution));
                 Ok(rra.extract_data(start, end, self.source.last_update))
             }
             None => bail!("unable to find RRA suitable ({:?}:{})", cf, resolution),
-- 
2.30.2