diff options
Diffstat (limited to 'third_party/rust/scroll/src/pwrite.rs')
| -rw-r--r-- | third_party/rust/scroll/src/pwrite.rs | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/third_party/rust/scroll/src/pwrite.rs b/third_party/rust/scroll/src/pwrite.rs index ab6d96157d..7a07f2daba 100644 --- a/third_party/rust/scroll/src/pwrite.rs +++ b/third_party/rust/scroll/src/pwrite.rs @@ -19,6 +19,13 @@ use crate::error; /// with 'read' switched for 'write' and 'From' switched with 'Into' so if you haven't yet you /// should read the documentation of `Pread` first. /// +/// As with `Pread`, note that in the particular case of the implementation of `Pwrite` for `[u8]`, +/// writing it at the length boundary of that slice will cause to write in an empty slice. +/// i.e. we make use of the fact that `&bytes[bytes.len()..]` will return an empty slice, rather +/// than returning an error. In the past, scroll returned an offset error. +/// In this case, this is relevant if you are writing an empty slice inside an empty slice and +/// expected this to work. +/// /// Unless you need to implement your own data store — that is either can't convert to `&[u8]` or /// have a data that does not expose a `&mut [u8]` — you will probably want to implement /// [TryIntoCtx](ctx/trait.TryIntoCtx.html) on your Rust types to be written. @@ -87,7 +94,7 @@ impl<Ctx: Copy, E: From<error::Error>> Pwrite<Ctx, E> for [u8] { offset: usize, ctx: Ctx, ) -> result::Result<usize, E> { - if offset >= self.len() { + if offset > self.len() { return Err(error::Error::BadOffset(offset).into()); } let dst = &mut self[offset..]; |