diff options
Diffstat (limited to 'crates/fparkan-nres')
| -rw-r--r-- | crates/fparkan-nres/src/lib.rs | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/crates/fparkan-nres/src/lib.rs b/crates/fparkan-nres/src/lib.rs index 778b76b..e82ca08 100644 --- a/crates/fparkan-nres/src/lib.rs +++ b/crates/fparkan-nres/src/lib.rs @@ -479,6 +479,23 @@ impl NresDocument { Ok(&self.bytes[entry.data_range.clone()]) } + /// Returns an owned view of an entry payload without copying its bytes. + /// + /// The returned owner is the immutable archive buffer. Consumers may retain + /// the view after dropping this document. + /// + /// # Errors + /// + /// Returns [`NresError::EntryIdOutOfRange`] when `id` is not present in + /// this document. + pub fn payload_view(&self, id: EntryId) -> Result<(Arc<[u8]>, Range<usize>), NresError> { + let entry = self.entry(id).ok_or_else(|| NresError::EntryIdOutOfRange { + id: id.0, + entry_count: saturating_u32_len(self.entries.len()), + })?; + Ok((Arc::clone(&self.bytes), entry.data_range.clone())) + } + /// Encodes the document according to the selected write profile. #[must_use] pub fn encode(&self, profile: WriteProfile) -> Vec<u8> { @@ -1213,6 +1230,8 @@ mod tests { assert_eq!(entry.data_range().end, HEADER_LEN + 1); assert_eq!(doc.header().directory_offset % 8, 0); assert_eq!(doc.payload(EntryId(0)).expect("payload"), b"x"); + let (owner, range) = doc.payload_view(EntryId(0)).expect("payload view"); + assert_eq!(&owner[range], b"x"); } #[test] |