diff options
| -rw-r--r-- | posts/signify-cgit.md | 50 |
1 files changed, 36 insertions, 14 deletions
diff --git a/posts/signify-cgit.md b/posts/signify-cgit.md index 7cbacba..ceea88c 100644 --- a/posts/signify-cgit.md +++ b/posts/signify-cgit.md @@ -27,24 +27,46 @@ Internally, Git stores the contents of a note as a saved to the object database and referred to by its hash. But Git must also store which commit a note belongs to. For this it uses a [tree](https://git-scm.com/book/en/v2/Git-Internals-Git-Objects#_tree_objects). -Normally, a tree maps blobs (or other trees) to paths in the repository. The -tree object that links notes, however, uses the commit blob as a "path". In the -following tree printed by -[`git-cat-file(1)`](https://git-scm.com/docs/git-cat-file), the note blobs are -on the left side whilst the commit blobs are on the right: +A tree is Git's way of encoding a directory: it contains a list of paths, and +maps them to blobs (files) or other trees (subdirectories). We can look at those +trees using [`git-cat-file(1)`](https://git-scm.com/docs/git-cat-file). For +example, the following is the tree for [this +commit](https://git.oriole.systems/quarg/commit/?id=7cd07362c4c13bfd01afa85a4666c491a020f330): ``` -100644 blob 6e3356af25efc1012279eb5e4c1bc5a31be16c31 22b910ba4985c6f1d91eaf9ac6c88e6fcb555115 -100644 blob c2daf0183bca1757216a792e9f770e8637db0d1b 36e553d961cc114c2f676108bdc28c7473a81fdc -100644 blob bc82006e27fc0c79b282976703d97f78fbf4ebef ebdc5a9bc9d5e303c08fb4a2126de02946b80d08 -100644 blob fc26da013cd8da9e95dd65433b9c8e423c20fbea f5121f6db3a18421f857d84c1e85bbc7c45cbd24 +$ git cat-file -p 6a81213f2e88a33835f2fb94015bda5dc04a397c +100644 blob 3feb78adc667d7bf4ad2cec4fb780b29ced25302 .gitignore +100644 blob 2149bd82c51e65c34d8aee87f96c4f1c1af8f6c1 LICENSE +100644 blob d397eaf5a75d0d30c4d9d2ffcd1007b44acc842a quarg.1 +040000 tree eee3c892c769bad3b7d883f0a162500406f67c3b quarg +100644 blob 1a861ec51a39cbefa0f5027995c358af2224ebbb setup.py ``` -The tree itself is then linked in a normal commit object that a special -[ref](https://git-scm.com/book/en/v2/Git-Internals-Git-References) points -to. By default, that is `refs/notes/commits`. One may think of that ref as -pointing to a special branch holding all the information on notes "published" to -that branch. +The tree object that links notes, however, uses the commit blob itself as a +"path". In the following tree (for +[this](https://git.oriole.systems/quarg/commit/?h=refs/notes/signatures/tar.gz&id=f12709c0843a89b5be37fe499b9928a8c11cbcd9) +commit) the note blob is on the left side whilst the commit blob ("path") is on +the right: + +``` +$ git cat-file -p 3a5fd837cae7e478b9a230f6c301c93efda7c1e2 +100644 blob 5c7ec832f83342aa460bb27b0b75e12695a98a53 43c9fb13e063cebfd08e741b67b9ec2317aed4b9 +``` + +Let's see which commit that is: + +``` +$ git show -s --pretty=oneline 43c9fb13e063cebfd08e741b67b9ec2317aed4b9 +43c9fb13e063cebfd08e741b67b9ec2317aed4b9 (tag: 0.1.2) Prepare for release of 0.1.2 +``` + +The note tree is then linked in a normal [commit +object](https://git.oriole.systems/quarg/commit/?h=refs/notes/signatures/tar.gz&id=f12709c0843a89b5be37fe499b9928a8c11cbcd9) +that a special +[ref](https://git-scm.com/book/en/v2/Git-Internals-Git-References) points to. By +default, that is `refs/notes/commits`. One may think of that ref as pointing to +a special branch holding all the information on notes "published" to that +branch. Instead of that default location, cgit looks in `refs/notes/signatures/<format>` for any signatures. For example, signatures for a gzip-compressed tarball are |