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Merge remote-tracking branch 'origin/master' into dependabot/nuget/build/all-dependencies-232486072c

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Adam Hathcock
2026-10-24 12:34:23 +01:00
parent 1fc761d5a5 e65e437c3d
commit bcf245e174
3 changed files with 7 additions and 10 deletions
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2
.agents/skills/zip-format/SKILL.md
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@@ -19,4 +19,4 @@ Use this skill for ZIP container-format work. It provides a local, SharpCompress
2. Open the relevant section in `references/zip-format.md` and use the source-file pointers before changing code.
3. For parsing changes, cross-check sync and async header readers: `ZipHeaderFactory.cs`, `ZipHeaderFactory.Async.cs`, `SeekableZipHeaderFactory.cs`, `StreamingZipHeaderFactory.cs`, `ZipFileEntry.cs`, `LocalEntryHeader.cs`, and `DirectoryEntryHeader.cs`.
4. For writer changes, verify local header, post-data descriptor, central directory, Zip64, and sync/async paths together.
5. For support claims, keep unsupported features explicit: central directory encryption, strong encryption records, XZ writing, non-standard compression methods, broad extra-field semantics, and non-seekable Zip64 writing.
5. For support claims, keep unsupported features explicit: central directory encryption, strong encryption records, XZ writing, non-standard compression methods, and broad extra-field semantics.

13
.agents/skills/zip-format/references/zip-format.md
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@@ -190,8 +190,7 @@ Important SharpCompress behavior:
- `StreamingZipHeaderFactory` reads post-data descriptors after the previous entry stream has been consumed.
- Streaming descriptor parsing has compatibility logic for 32-bit and 64-bit sizes.
- `ZipWriter` writes a descriptor with signature for non-seekable output when Zip64 is not required.
- `ZipWriter` intentionally rejects Zip64 on non-seekable streams.
- `ZipWriter` writes post-data descriptors for non-seekable output; when `ZipWriterOptions.UseZip64` is enabled, it writes the ZIP64 headers and 64-bit descriptors required by that mode.
## General Purpose Bit Flags
@@ -309,7 +308,7 @@ SharpCompress write behavior:
- `ZipWriterOptions.UseZip64` controls whether local headers reserve Zip64 extra data for entries.
- `ZipWriter` emits Zip64 EOCD and locator when entry counts, central directory size, or offsets require them.
- Non-seekable Zip64 writing is rejected because current post-data descriptor handling cannot safely represent the required Zip64 values in all cases.
- Non-seekable output supports Zip64 when `ZipWriterOptions.UseZip64` is enabled before writing entries; the writer emits the required 64-bit data descriptors.
## Names, Comments, And Encoding
@@ -372,8 +371,8 @@ Current ZIP support summary from `docs/FORMATS.md` and implementation:
| Shrink | Yes | No | Legacy method 1 |
| Reduce | Yes | No | Legacy methods 2-5 |
| Implode | Yes | No | Legacy method 6 |
| Zip64 | Yes | Yes | Writing requires seekable stream for Zip64 |
| Data descriptors | Yes | Yes | Writer uses them for non-seekable non-Zip64 output |
| Zip64 | Yes | Yes | Non-seekable writing is supported when enabled with `ZipWriterOptions.UseZip64` |
| Data descriptors | Yes | Yes | Non-seekable output uses descriptors; Zip64 mode uses 64-bit descriptors |
| Traditional PKWARE encryption | Yes | No | Password required |
| WinZip AES | Yes | No | Method 99 + extra field `0x9901` |
| Split/multi-volume ZIP | Yes | No | Use Archive API |
@@ -397,8 +396,7 @@ Important writer rules:
- Local headers are written before payload data.
- Seekable output lets SharpCompress patch CRC and size fields after compression.
- Non-seekable output uses post-data descriptors for non-Zip64 entries.
- Zip64 on non-seekable output is rejected.
- Non-seekable output uses post-data descriptors. Set `ZipWriterOptions.UseZip64` before writing entries that may exceed classic ZIP limits; Zip64 mode emits 64-bit descriptors.
- Zero-byte file entries are normalized to stored/no compression in the central directory.
- Central directory entries are written on `Dispose` / `DisposeAsync`; callers must dispose writers to finalize archives.
@@ -411,7 +409,6 @@ Keep these limitations explicit in code comments, docs, and tests:
- No Deflate64, Shrink, Reduce, or Implode writing.
- No general-purpose central directory encryption support.
- No broad APPNOTE strong encryption record support beyond current traditional PKWARE and WinZip AES read paths.
- No non-seekable Zip64 writing.
- Unknown extra fields are not semantically modeled unless explicitly implemented.
- ZipReader cannot seek across multi-volume/split archive parts; use ZipArchive for split archives.

2
AGENTS.md
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@@ -196,7 +196,7 @@ referenced for every project via `Directory.Packages.props`).
- Tar writing supports uncompressed Tar, GZip, BZip2, and LZip wrappers
### Zip-Specific Considerations
- Supports Zip64 for large files (seekable streams only)
- Supports Zip64 for large files on seekable streams and non-seekable output when `ZipWriterOptions.UseZip64` is enabled before writing entries; non-seekable output uses 64-bit data descriptors.
- Supports PKWare and WinZip AES encryption
- Multiple compression methods: None, Shrink, Reduce, Implode, DEFLATE, Deflate64, BZip2, LZMA, PPMd
- Encrypted LZMA is not supported