diff options
author | Mikail Bagishov <bagishov.mikail@yandex.ru> | 2020-04-23 21:19:56 +0300 |
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committer | GitHub <noreply@github.com> | 2020-04-23 20:19:56 +0200 |
commit | 236629d1be7208612cbe5388e7ffebf85b73c157 (patch) | |
tree | 73ca0d102a5220d7693c4cacbdc0523fe7d1b1aa /tokio | |
parent | f83f6388c42aa62c2096073b1dd80459189d7ea9 (diff) |
stream: fix panic in Merge and Chain size_hint (#2430)
Diffstat (limited to 'tokio')
-rw-r--r-- | tokio/src/stream/chain.rs | 10 | ||||
-rw-r--r-- | tokio/src/stream/merge.rs | 10 | ||||
-rw-r--r-- | tokio/src/stream/mod.rs | 13 | ||||
-rw-r--r-- | tokio/tests/stream_chain.rs | 24 | ||||
-rw-r--r-- | tokio/tests/stream_merge.rs | 24 |
5 files changed, 63 insertions, 18 deletions
diff --git a/tokio/src/stream/chain.rs b/tokio/src/stream/chain.rs index 5f0324a4..6124c91e 100644 --- a/tokio/src/stream/chain.rs +++ b/tokio/src/stream/chain.rs @@ -44,14 +44,6 @@ where } fn size_hint(&self) -> (usize, Option<usize>) { - let (a_lower, a_upper) = self.a.size_hint(); - let (b_lower, b_upper) = self.b.size_hint(); - - let upper = match (a_upper, b_upper) { - (Some(a_upper), Some(b_upper)) => Some(a_upper + b_upper), - _ => None, - }; - - (a_lower + b_lower, upper) + super::merge_size_hints(self.a.size_hint(), self.b.size_hint()) } } diff --git a/tokio/src/stream/merge.rs b/tokio/src/stream/merge.rs index 4850cd40..50ba518c 100644 --- a/tokio/src/stream/merge.rs +++ b/tokio/src/stream/merge.rs @@ -52,15 +52,7 @@ where } fn size_hint(&self) -> (usize, Option<usize>) { - let (a_lower, a_upper) = self.a.size_hint(); - let (b_lower, b_upper) = self.b.size_hint(); - - let upper = match (a_upper, b_upper) { - (Some(a_upper), Some(b_upper)) => Some(a_upper + b_upper), - _ => None, - }; - - (a_lower + b_lower, upper) + super::merge_size_hints(self.a.size_hint(), self.b.size_hint()) } } diff --git a/tokio/src/stream/mod.rs b/tokio/src/stream/mod.rs index 307ead5f..a59bdfcd 100644 --- a/tokio/src/stream/mod.rs +++ b/tokio/src/stream/mod.rs @@ -817,3 +817,16 @@ pub trait StreamExt: Stream { } impl<St: ?Sized> StreamExt for St where St: Stream {} + +/// Merge the size hints from two streams. +fn merge_size_hints( + (left_low, left_high): (usize, Option<usize>), + (right_low, right_hign): (usize, Option<usize>), +) -> (usize, Option<usize>) { + let low = left_low.saturating_add(right_low); + let high = match (left_high, right_hign) { + (Some(h1), Some(h2)) => h1.checked_add(h2), + _ => None, + }; + (low, high) +} diff --git a/tokio/tests/stream_chain.rs b/tokio/tests/stream_chain.rs index 0e14618b..98461a8c 100644 --- a/tokio/tests/stream_chain.rs +++ b/tokio/tests/stream_chain.rs @@ -69,3 +69,27 @@ async fn pending_first() { assert_eq!(stream.size_hint(), (0, None)); assert_eq!(None, assert_ready!(stream.poll_next())); } + +#[test] +fn size_overflow() { + struct Monster; + + impl tokio::stream::Stream for Monster { + type Item = (); + fn poll_next( + self: std::pin::Pin<&mut Self>, + _cx: &mut std::task::Context<'_>, + ) -> std::task::Poll<Option<()>> { + panic!() + } + + fn size_hint(&self) -> (usize, Option<usize>) { + (usize::max_value(), Some(usize::max_value())) + } + } + + let m1 = Monster; + let m2 = Monster; + let m = m1.chain(m2); + assert_eq!(m.size_hint(), (usize::max_value(), None)); +} diff --git a/tokio/tests/stream_merge.rs b/tokio/tests/stream_merge.rs index f0168d72..45ecdcb6 100644 --- a/tokio/tests/stream_merge.rs +++ b/tokio/tests/stream_merge.rs @@ -52,3 +52,27 @@ async fn merge_async_streams() { assert!(rx.is_woken()); assert_eq!(None, assert_ready!(rx.poll_next())); } + +#[test] +fn size_overflow() { + struct Monster; + + impl tokio::stream::Stream for Monster { + type Item = (); + fn poll_next( + self: std::pin::Pin<&mut Self>, + _cx: &mut std::task::Context<'_>, + ) -> std::task::Poll<Option<()>> { + panic!() + } + + fn size_hint(&self) -> (usize, Option<usize>) { + (usize::max_value(), Some(usize::max_value())) + } + } + + let m1 = Monster; + let m2 = Monster; + let m = m1.merge(m2); + assert_eq!(m.size_hint(), (usize::max_value(), None)); +} |