Initial checkin from CRI-O repo

Signed-off-by: Matthew Heon <matthew.heon@gmail.com>

1 files changed, 137 insertions, 0 deletions

diff --git a/vendor/github.com/vbatts/tar-split/README.md b/vendor/github.com/vbatts/tar-split/README.md
new file mode 100644
index 000000000..4c544d823
--- /dev/null
+++ b/vendor/github.com/vbatts/tar-split/README.md
@@ -0,0 +1,137 @@
+# tar-split
+
+[![Build Status](https://travis-ci.org/vbatts/tar-split.svg?branch=master)](https://travis-ci.org/vbatts/tar-split)
+
+Pristinely disassembling a tar archive, and stashing needed raw bytes and offsets to reassemble a validating original archive.
+
+## Docs
+
+Code API for libraries provided by `tar-split`:
+
+* https://godoc.org/github.com/vbatts/tar-split/tar/asm
+* https://godoc.org/github.com/vbatts/tar-split/tar/storage
+* https://godoc.org/github.com/vbatts/tar-split/archive/tar
+
+## Install
+
+The command line utilitiy is installable via:
+
+```bash
+go get github.com/vbatts/tar-split/cmd/tar-split
+```
+
+## Usage
+
+For cli usage, see its [README.md](cmd/tar-split/README.md).
+For the library see the [docs](#docs)
+
+## Demo
+
+### Basic disassembly and assembly
+
+This demonstrates the `tar-split` command and how to assemble a tar archive from the `tar-data.json.gz`
+
+
+![basic cmd demo thumbnail](https://i.ytimg.com/vi/vh5wyjIOBtc/2.jpg?time=1445027151805)
+[youtube video of basic command demo](https://youtu.be/vh5wyjIOBtc)
+
+### Docker layer preservation
+
+This demonstrates the tar-split integration for docker-1.8. Providing consistent tar archives for the image layer content.
+
+![docker tar-split demo](https://i.ytimg.com/vi_webp/vh5wyjIOBtc/default.webp)
+[youtube vide of docker layer checksums](https://youtu.be/tV_Dia8E8xw)
+
+## Caveat
+
+Eventually this should detect TARs that this is not possible with.
+
+For example stored sparse files that have "holes" in them, will be read as a
+contiguous file, though the archive contents may be recorded in sparse format.
+Therefore when adding the file payload to a reassembled tar, to achieve
+identical output, the file payload would need be precisely re-sparsified. This
+is not something I seek to fix imediately, but would rather have an alert that
+precise reassembly is not possible.
+(see more http://www.gnu.org/software/tar/manual/html_node/Sparse-Formats.html)
+
+
+Other caveat, while tar archives support having multiple file entries for the
+same path, we will not support this feature. If there are more than one entries
+with the same path, expect an err (like `ErrDuplicatePath`) or a resulting tar
+stream that does not validate your original checksum/signature.
+
+## Contract
+
+Do not break the API of stdlib `archive/tar` in our fork (ideally find an upstream mergeable solution).
+
+## Std Version
+
+The version of golang stdlib `archive/tar` is from go1.6
+It is minimally extended to expose the raw bytes of the TAR, rather than just the marshalled headers and file stream.
+
+
+## Design
+
+See the [design](concept/DESIGN.md).
+
+## Stored Metadata
+
+Since the raw bytes of the headers and padding are stored, you may be wondering
+what the size implications are. The headers are at least 512 bytes per
+file (sometimes more), at least 1024 null bytes on the end, and then various
+padding. This makes for a constant linear growth in the stored metadata, with a
+naive storage implementation.
+
+First we'll get an archive to work with. For repeatability, we'll make an
+archive from what you've just cloned:
+
+```bash
+git archive --format=tar -o tar-split.tar HEAD .
+```
+
+```bash
+$ go get github.com/vbatts/tar-split/cmd/tar-split
+$ tar-split checksize ./tar-split.tar
+inspecting "tar-split.tar" (size 210k)
+ -- number of files: 50
+ -- size of metadata uncompressed: 53k
+ -- size of gzip compressed metadata: 3k
+```
+
+So assuming you've managed the extraction of the archive yourself, for reuse of
+the file payloads from a relative path, then the only additional storage
+implications are as little as 3kb.
+
+But let's look at a larger archive, with many files.
+
+```bash
+$ ls -sh ./d.tar
+1.4G ./d.tar
+$ tar-split checksize ~/d.tar 
+inspecting "/home/vbatts/d.tar" (size 1420749k)
+ -- number of files: 38718
+ -- size of metadata uncompressed: 43261k
+ -- size of gzip compressed metadata: 2251k
+```
+
+Here, an archive with 38,718 files has a compressed footprint of about 2mb.
+
+Rolling the null bytes on the end of the archive, we will assume a
+bytes-per-file rate for the storage implications.
+
+| uncompressed | compressed |
+| :----------: | :--------: |
+| ~ 1kb per/file | 0.06kb per/file |
+
+
+## What's Next?
+
+* More implementations of storage Packer and Unpacker
+* More implementations of FileGetter and FilePutter
+* would be interesting to have an assembler stream that implements `io.Seeker`
+
+
+## License
+
+See [LICENSE](LICENSE)
+