lib: Add delta calculation with wrapping operations to avoid overflows

vpetrigo · Nov 9, 2022 · e140d06 · e140d06
1 parent 58fa630
commit e140d06
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Showing 2 changed files with 5 additions and 3 deletions.
diff --git a/Cargo.toml b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "sntpc"
-version = "0.3.1"
+version = "0.3.2"
 description = "Library for making SNTP requests"
 homepage = "https://github.com/vpetrigo/sntpc"
 repository = "https://github.com/vpetrigo/sntpc"

diff --git a/src/lib.rs b/src/lib.rs
@@ -1003,7 +1003,7 @@ fn roundtrip_calculate(
     t4: u64,
     units: Units,
 ) -> u64 {
-    let delta = (t4 - t1) - (t3 - t2);
+    let delta = t4.wrapping_sub(t1).wrapping_sub(t3.wrapping_sub(t2));
     let delta_sec = (delta & SECONDS_MASK) >> 32;
     let delta_sec_fraction = delta & SECONDS_FRAC_MASK;
 
@@ -1018,7 +1018,9 @@ fn roundtrip_calculate(
 }
 
 fn offset_calculate(t1: u64, t2: u64, t3: u64, t4: u64, units: Units) -> i64 {
-    let theta = (t2.wrapping_sub(t1) as i64).wrapping_add(t3.wrapping_sub(t4) as i64) / 2;
+    let theta = (t2.wrapping_sub(t1) as i64)
+        .wrapping_add(t3.wrapping_sub(t4) as i64)
+        / 2;
     let theta_sec = (theta.abs() as u64 & SECONDS_MASK) >> 32;
     let theta_sec_fraction = theta.abs() as u64 & SECONDS_FRAC_MASK;