Continue the move of existing Documentation/technical/* protocol and file-format documentation into our main documentation space. By moving the documentation for the commit-graph format into man section 5 and the new "developerinterfaces" category. This change is split from subsequent commits due to the relatively large amount of ASCIIDOC formatting changes that are required. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx> --- Documentation/Makefile | 1 + Documentation/git-commit-graph.txt | 5 ++ ...-format.txt => gitformat-commit-graph.txt} | 47 +++++++++++++------ Documentation/technical/chunk-format.txt | 4 +- command-list.txt | 2 + 5 files changed, 42 insertions(+), 17 deletions(-) rename Documentation/{technical/commit-graph-format.txt => gitformat-commit-graph.txt} (88%) diff --git a/Documentation/Makefile b/Documentation/Makefile index 1a4a545f44a..e7bd72bb84e 100644 --- a/Documentation/Makefile +++ b/Documentation/Makefile @@ -25,6 +25,7 @@ MAN1_TXT += gitweb.txt # man5 / man7 guides (note: new guides should also be added to command-list.txt) MAN5_TXT += gitattributes.txt MAN5_TXT += gitformat-bundle.txt +MAN5_TXT += gitformat-commit-graph.txt MAN5_TXT += githooks.txt MAN5_TXT += gitignore.txt MAN5_TXT += gitmailmap.txt diff --git a/Documentation/git-commit-graph.txt b/Documentation/git-commit-graph.txt index e1f48c95b3c..047decdb65b 100644 --- a/Documentation/git-commit-graph.txt +++ b/Documentation/git-commit-graph.txt @@ -143,6 +143,11 @@ $ git rev-parse HEAD | git commit-graph write --stdin-commits --append ------------------------------------------------ +FILE FORMAT +----------- + +see linkgit:gitformat-commit-graph[5]. + GIT --- Part of the linkgit:git[1] suite diff --git a/Documentation/technical/commit-graph-format.txt b/Documentation/gitformat-commit-graph.txt similarity index 88% rename from Documentation/technical/commit-graph-format.txt rename to Documentation/gitformat-commit-graph.txt index 484b185ba98..108dc2295c0 100644 --- a/Documentation/technical/commit-graph-format.txt +++ b/Documentation/gitformat-commit-graph.txt @@ -1,5 +1,18 @@ -Git commit graph format -======================= +gitformat-commit-graph(5) +========================= + +NAME +---- +gitformat-commit-graph - Git commit graph format + +SYNOPSIS +-------- +[verse] +$GIT_DIR/objects/info/commit-graph +$GIT_DIR/objects/info/commit-graphs/* + +DESCRIPTION +----------- The Git commit graph stores a list of commit OIDs and some associated metadata, including: @@ -30,7 +43,7 @@ and hash type. All multi-byte numbers are in network byte order. -HEADER: +=== HEADER: 4-byte signature: The signature is: {'C', 'G', 'P', 'H'} @@ -52,7 +65,7 @@ HEADER: We infer the length (H*B) of the Base Graphs chunk from this value. -CHUNK LOOKUP: +=== CHUNK LOOKUP: (C + 1) * 12 bytes listing the table of contents for the chunks: First 4 bytes describe the chunk id. Value 0 is a terminating label. @@ -68,17 +81,17 @@ CHUNK LOOKUP: these chunks may be given in any order. Chunks are required unless otherwise specified. -CHUNK DATA: +=== CHUNK DATA: - OID Fanout (ID: {'O', 'I', 'D', 'F'}) (256 * 4 bytes) +==== OID Fanout (ID: {'O', 'I', 'D', 'F'}) (256 * 4 bytes) The ith entry, F[i], stores the number of OIDs with first byte at most i. Thus F[255] stores the total number of commits (N). - OID Lookup (ID: {'O', 'I', 'D', 'L'}) (N * H bytes) +==== OID Lookup (ID: {'O', 'I', 'D', 'L'}) (N * H bytes) The OIDs for all commits in the graph, sorted in ascending order. - Commit Data (ID: {'C', 'D', 'A', 'T' }) (N * (H + 16) bytes) +==== Commit Data (ID: {'C', 'D', 'A', 'T' }) (N * (H + 16) bytes) * The first H bytes are for the OID of the root tree. * The next 8 bytes are for the positions of the first two parents of the ith commit. Stores value 0x70000000 if no parent in that @@ -93,7 +106,7 @@ CHUNK DATA: 2 bits of the lowest byte, storing the 33rd and 34th bit of the commit time. - Generation Data (ID: {'G', 'D', 'A', '2' }) (N * 4 bytes) [Optional] +==== Generation Data (ID: {'G', 'D', 'A', '2' }) (N * 4 bytes) [Optional] * This list of 4-byte values store corrected commit date offsets for the commits, arranged in the same order as commit data chunk. * If the corrected commit date offset cannot be stored within 31 bits, @@ -104,7 +117,7 @@ CHUNK DATA: by compatible versions of Git and in case of split commit-graph chains, the topmost layer also has Generation Data chunk. - Generation Data Overflow (ID: {'G', 'D', 'O', '2' }) [Optional] +==== Generation Data Overflow (ID: {'G', 'D', 'O', '2' }) [Optional] * This list of 8-byte values stores the corrected commit date offsets for commits with corrected commit date offsets that cannot be stored within 31 bits. @@ -112,7 +125,7 @@ CHUNK DATA: chunk is present and atleast one corrected commit date offset cannot be stored within 31 bits. - Extra Edge List (ID: {'E', 'D', 'G', 'E'}) [Optional] +==== Extra Edge List (ID: {'E', 'D', 'G', 'E'}) [Optional] This list of 4-byte values store the second through nth parents for all octopus merges. The second parent value in the commit data stores an array position within this list along with the most-significant bit @@ -120,14 +133,14 @@ CHUNK DATA: positions for the parents until reaching a value with the most-significant bit on. The other bits correspond to the position of the last parent. - Bloom Filter Index (ID: {'B', 'I', 'D', 'X'}) (N * 4 bytes) [Optional] +==== Bloom Filter Index (ID: {'B', 'I', 'D', 'X'}) (N * 4 bytes) [Optional] * The ith entry, BIDX[i], stores the number of bytes in all Bloom filters from commit 0 to commit i (inclusive) in lexicographic order. The Bloom filter for the i-th commit spans from BIDX[i-1] to BIDX[i] (plus header length), where BIDX[-1] is 0. * The BIDX chunk is ignored if the BDAT chunk is not present. - Bloom Filter Data (ID: {'B', 'D', 'A', 'T'}) [Optional] +==== Bloom Filter Data (ID: {'B', 'D', 'A', 'T'}) [Optional] * It starts with header consisting of three unsigned 32-bit integers: - Version of the hash algorithm being used. We currently only support value 1 which corresponds to the 32-bit version of the murmur3 hash @@ -147,13 +160,13 @@ CHUNK DATA: of length one, with either all bits set to zero or one respectively. * The BDAT chunk is present if and only if BIDX is present. - Base Graphs List (ID: {'B', 'A', 'S', 'E'}) [Optional] +==== Base Graphs List (ID: {'B', 'A', 'S', 'E'}) [Optional] This list of H-byte hashes describe a set of B commit-graph files that form a commit-graph chain. The graph position for the ith commit in this file's OID Lookup chunk is equal to i plus the number of commits in all base graphs. If B is non-zero, this chunk must exist. -TRAILER: +=== TRAILER: H-byte HASH-checksum of all of the above. @@ -164,3 +177,7 @@ the number '2' in their chunk IDs because a previous version of Git wrote possibly erroneous data in these chunks with the IDs "GDAT" and "GDOV". By changing the IDs, newer versions of Git will silently ignore those older chunks and write the new information without trusting the incorrect data. + +GIT +--- +Part of the linkgit:git[1] suite diff --git a/Documentation/technical/chunk-format.txt b/Documentation/technical/chunk-format.txt index 593614fceda..f36ce42f37c 100644 --- a/Documentation/technical/chunk-format.txt +++ b/Documentation/technical/chunk-format.txt @@ -6,7 +6,7 @@ sections of the file. This allows structured access to a large file by scanning a small "table of contents" for the remaining data. This common format is used by the `commit-graph` and `multi-pack-index` files. See link:technical/pack-format.html[the `multi-pack-index` format] and -link:technical/commit-graph-format.html[the `commit-graph` format] for +the `commit-graph` format in linkgit:gitformat-commit-graph[5] for how they use the chunks to describe structured data. A chunk-based file format begins with some header information custom to @@ -108,7 +108,7 @@ for future formats: * *commit-graph:* see `write_commit_graph_file()` and `parse_commit_graph()` in `commit-graph.c` for how the chunk-format API is used to write and parse the commit-graph file format documented in - link:technical/commit-graph-format.html[the commit-graph file format]. + the commit-graph file format in linkgit:gitformat-commit-graph[5]. * *multi-pack-index:* see `write_midx_internal()` and `load_multi_pack_index()` in `midx.c` for how the chunk-format API is used to write and diff --git a/command-list.txt b/command-list.txt index 1950c4ccd9c..44e244a76f6 100644 --- a/command-list.txt +++ b/command-list.txt @@ -210,6 +210,8 @@ gitdiffcore guide giteveryday guide gitfaq guide gitformat-bundle developerinterfaces +gitformat-bundle developerinterfaces +gitformat-commit-graph developerinterfaces gitglossary guide githooks userinterfaces gitignore userinterfaces -- 2.37.1.1095.g64a1e8362fd