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-rw-r--r--posts/signify-cgit.md50
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