summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorMasaya Suzuki <masayasuzuki@google.com>2020-02-07 20:42:25 (GMT)
committerJunio C Hamano <gitster@pobox.com>2020-02-07 20:47:02 (GMT)
commit7378ec90e1c59610dfcac8a4bce7a9d29681380d (patch)
treeb3db8133ba16d098ea1b5b749535653ece0dacb6
parentb6d4d82bd5a49197d5d2f4f81c08da0d461cfcf1 (diff)
downloadgit-7378ec90e1c59610dfcac8a4bce7a9d29681380d.zip
git-7378ec90e1c59610dfcac8a4bce7a9d29681380d.tar.gz
git-7378ec90e1c59610dfcac8a4bce7a9d29681380d.tar.bz2
doc: describe Git bundle format
The bundle format was not documented. Describe the format with ABNF and explain the meaning of each part. Signed-off-by: Masaya Suzuki <masayasuzuki@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
-rw-r--r--Documentation/technical/bundle-format.txt48
1 files changed, 48 insertions, 0 deletions
diff --git a/Documentation/technical/bundle-format.txt b/Documentation/technical/bundle-format.txt
new file mode 100644
index 0000000..0e82815
--- /dev/null
+++ b/Documentation/technical/bundle-format.txt
@@ -0,0 +1,48 @@
+= Git bundle v2 format
+
+The Git bundle format is a format that represents both refs and Git objects.
+
+== Format
+
+We will use ABNF notation to define the Git bundle format. See
+protocol-common.txt for the details.
+
+----
+bundle = signature *prerequisite *reference LF pack
+signature = "# v2 git bundle" LF
+
+prerequisite = "-" obj-id SP comment LF
+comment = *CHAR
+reference = obj-id SP refname LF
+
+pack = ... ; packfile
+----
+
+== Semantics
+
+A Git bundle consists of three parts.
+
+* "Prerequisites" lists the objects that are NOT included in the bundle and the
+ reader of the bundle MUST already have, in order to use the data in the
+ bundle. The objects stored in the bundle may refer to prerequisite objects and
+ anything reachable from them (e.g. a tree object in the bundle can reference
+ a blob that is reachable from a prerequisite) and/or expressed as a delta
+ against prerequisite objects.
+
+* "References" record the tips of the history graph, iow, what the reader of the
+ bundle CAN "git fetch" from it.
+
+* "Pack" is the pack data stream "git fetch" would send, if you fetch from a
+ repository that has the references recorded in the "References" above into a
+ repository that has references pointing at the objects listed in
+ "Prerequisites" above.
+
+In the bundle format, there can be a comment following a prerequisite obj-id.
+This is a comment and it has no specific meaning. The writer of the bundle MAY
+put any string here. The reader of the bundle MUST ignore the comment.
+
+=== Note on the shallow clone and a Git bundle
+
+Note that the prerequisites does not represent a shallow-clone boundary. The
+semantics of the prerequisites and the shallow-clone boundaries are different,
+and the Git bundle v2 format cannot represent a shallow clone repository.