From c4d25228ebb22a60f1fcb267e19c503bab708cdc Mon Sep 17 00:00:00 2001 From: Derrick Stolee Date: Thu, 12 Jul 2018 15:39:33 -0400 Subject: config: create core.multiPackIndex setting The core.multiPackIndex config setting controls the multi-pack- index (MIDX) feature. If false, the setting will disable all reads from the multi-pack-index file. Read this config setting in the new prepare_multi_pack_index_one() which is called during prepare_packed_git(). This check is run once per repository. Add comparison commands in t5319-multi-pack-index.sh to check typical Git behavior remains the same as the config setting is turned on and off. This currently includes 'git rev-list' and 'git log' commands to trigger several object database reads. Currently, these would only catch an error in the prepare_multi_pack_index_one(), but with later commits will catch errors in object lookups, abbreviations, and approximate object counts. Signed-off-by: Derrick Stolee Signed-off-by: Junio C Hamano --- Documentation/config.txt | 5 +++++ midx.c | 25 ++++++++++++++++++++++ midx.h | 5 +++++ object-store.h | 7 +++++++ packfile.c | 6 +++++- t/t5319-multi-pack-index.sh | 51 +++++++++++++++++++++++++++++++++------------ 6 files changed, 85 insertions(+), 14 deletions(-) diff --git a/Documentation/config.txt b/Documentation/config.txt index ab641bf5a9..25f817ca42 100644 --- a/Documentation/config.txt +++ b/Documentation/config.txt @@ -908,6 +908,11 @@ core.commitGraph:: Enable git commit graph feature. Allows reading from the commit-graph file. +core.multiPackIndex:: + Use the multi-pack-index file to track multiple packfiles using a + single index. See link:technical/multi-pack-index.html[the + multi-pack-index design document]. + core.sparseCheckout:: Enable "sparse checkout" feature. See section "Sparse checkout" in linkgit:git-read-tree[1] for more information. diff --git a/midx.c b/midx.c index e83110ae92..4090cf4ca4 100644 --- a/midx.c +++ b/midx.c @@ -1,4 +1,5 @@ #include "cache.h" +#include "config.h" #include "csum-file.h" #include "dir.h" #include "lockfile.h" @@ -177,6 +178,30 @@ cleanup_fail: return NULL; } +int prepare_multi_pack_index_one(struct repository *r, const char *object_dir) +{ + struct multi_pack_index *m = r->objects->multi_pack_index; + struct multi_pack_index *m_search; + int config_value; + + if (repo_config_get_bool(r, "core.multipackindex", &config_value) || + !config_value) + return 0; + + for (m_search = m; m_search; m_search = m_search->next) + if (!strcmp(object_dir, m_search->object_dir)) + return 1; + + r->objects->multi_pack_index = load_multi_pack_index(object_dir); + + if (r->objects->multi_pack_index) { + r->objects->multi_pack_index->next = m; + return 1; + } + + return 0; +} + static size_t write_midx_header(struct hashfile *f, unsigned char num_chunks, uint32_t num_packs) diff --git a/midx.h b/midx.h index e15966272f..9bcfc82d2e 100644 --- a/midx.h +++ b/midx.h @@ -1,7 +1,11 @@ #ifndef __MIDX_H__ #define __MIDX_H__ +#include "repository.h" + struct multi_pack_index { + struct multi_pack_index *next; + int fd; const unsigned char *data; @@ -25,6 +29,7 @@ struct multi_pack_index { }; struct multi_pack_index *load_multi_pack_index(const char *object_dir); +int prepare_multi_pack_index_one(struct repository *r, const char *object_dir); int write_midx_file(const char *object_dir); diff --git a/object-store.h b/object-store.h index 13a766aea8..c2b162489a 100644 --- a/object-store.h +++ b/object-store.h @@ -105,6 +105,13 @@ struct raw_object_store { */ struct oidmap *replace_map; + /* + * private data + * + * should only be accessed directly by packfile.c and midx.c + */ + struct multi_pack_index *multi_pack_index; + /* * private data * diff --git a/packfile.c b/packfile.c index 3d652212c6..5d4493dbf4 100644 --- a/packfile.c +++ b/packfile.c @@ -15,6 +15,7 @@ #include "tree-walk.h" #include "tree.h" #include "object-store.h" +#include "midx.h" char *odb_pack_name(struct strbuf *buf, const unsigned char *sha1, @@ -935,10 +936,13 @@ static void prepare_packed_git(struct repository *r) if (r->objects->packed_git_initialized) return; + prepare_multi_pack_index_one(r, r->objects->objectdir); prepare_packed_git_one(r, r->objects->objectdir, 1); prepare_alt_odb(r); - for (alt = r->objects->alt_odb_list; alt; alt = alt->next) + for (alt = r->objects->alt_odb_list; alt; alt = alt->next) { + prepare_multi_pack_index_one(r, alt->path); prepare_packed_git_one(r, alt->path, 0); + } rearrange_packed_git(r); prepare_packed_git_mru(r); r->objects->packed_git_initialized = 1; diff --git a/t/t5319-multi-pack-index.sh b/t/t5319-multi-pack-index.sh index 4a4fa26f7a..b9661c7c66 100755 --- a/t/t5319-multi-pack-index.sh +++ b/t/t5319-multi-pack-index.sh @@ -3,6 +3,8 @@ test_description='multi-pack-indexes' . ./test-lib.sh +objdir=.git/objects + midx_read_expect () { NUM_PACKS=$1 NUM_OBJECTS=$2 @@ -76,18 +78,35 @@ test_expect_success 'create objects' ' ' test_expect_success 'write midx with one v1 pack' ' - pack=$(git pack-objects --index-version=1 pack/test expect && + git -c core.multiPackIndex=true $1 >actual && + test_cmp expect actual +} + +compare_results_with_midx () { + MSG=$1 + test_expect_success "check normal git operations: $MSG" ' + midx_git_two_modes "rev-list --objects --all" && + midx_git_two_modes "log --raw" + ' +} + test_expect_success 'write midx with one v2 pack' ' - git pack-objects --index-version=2,0x40 pack/test [] corrupt_data () { file=$1 -- cgit v1.2.3