diff --git a/commit-graph.c b/commit-graph.c index a0d01d2e66..9bc110b4bd 100644 --- a/commit-graph.c +++ b/commit-graph.c @@ -38,11 +38,13 @@ void git_test_write_commit_graph_or_die(void) #define GRAPH_CHUNKID_OIDFANOUT 0x4f494446 /* "OIDF" */ #define GRAPH_CHUNKID_OIDLOOKUP 0x4f49444c /* "OIDL" */ #define GRAPH_CHUNKID_DATA 0x43444154 /* "CDAT" */ +#define GRAPH_CHUNKID_GENERATION_DATA 0x47444154 /* "GDAT" */ +#define GRAPH_CHUNKID_GENERATION_DATA_OVERFLOW 0x47444f56 /* "GDOV" */ #define GRAPH_CHUNKID_EXTRAEDGES 0x45444745 /* "EDGE" */ #define GRAPH_CHUNKID_BLOOMINDEXES 0x42494458 /* "BIDX" */ #define GRAPH_CHUNKID_BLOOMDATA 0x42444154 /* "BDAT" */ #define GRAPH_CHUNKID_BASE 0x42415345 /* "BASE" */ -#define MAX_NUM_CHUNKS 7 +#define MAX_NUM_CHUNKS 9 #define GRAPH_DATA_WIDTH (the_hash_algo->rawsz + 16) @@ -61,6 +63,8 @@ void git_test_write_commit_graph_or_die(void) #define GRAPH_MIN_SIZE (GRAPH_HEADER_SIZE + 4 * GRAPH_CHUNKLOOKUP_WIDTH \ + GRAPH_FANOUT_SIZE + the_hash_algo->rawsz) +#define CORRECTED_COMMIT_DATE_OFFSET_OVERFLOW (1ULL << 31) + /* Remember to update object flag allocation in object.h */ #define REACHABLE (1u<<15) @@ -394,6 +398,20 @@ struct commit_graph *parse_commit_graph(struct repository *r, graph->chunk_commit_data = data + chunk_offset; break; + case GRAPH_CHUNKID_GENERATION_DATA: + if (graph->chunk_generation_data) + chunk_repeated = 1; + else + graph->chunk_generation_data = data + chunk_offset; + break; + + case GRAPH_CHUNKID_GENERATION_DATA_OVERFLOW: + if (graph->chunk_generation_data_overflow) + chunk_repeated = 1; + else + graph->chunk_generation_data_overflow = data + chunk_offset; + break; + case GRAPH_CHUNKID_EXTRAEDGES: if (graph->chunk_extra_edges) chunk_repeated = 1; @@ -754,8 +772,8 @@ static void fill_commit_graph_info(struct commit *item, struct commit_graph *g, { const unsigned char *commit_data; struct commit_graph_data *graph_data; - uint32_t lex_index; - uint64_t date_high, date_low; + uint32_t lex_index, offset_pos; + uint64_t date_high, date_low, offset; while (pos < g->num_commits_in_base) g = g->base_graph; @@ -773,7 +791,19 @@ static void fill_commit_graph_info(struct commit *item, struct commit_graph *g, date_low = get_be32(commit_data + g->hash_len + 12); item->date = (timestamp_t)((date_high << 32) | date_low); - graph_data->generation = get_be32(commit_data + g->hash_len + 8) >> 2; + if (g->chunk_generation_data) { + offset = (timestamp_t)get_be32(g->chunk_generation_data + sizeof(uint32_t) * lex_index); + + if (offset & CORRECTED_COMMIT_DATE_OFFSET_OVERFLOW) { + if (!g->chunk_generation_data_overflow) + die(_("commit-graph requires overflow generation data but has none")); + + offset_pos = offset ^ CORRECTED_COMMIT_DATE_OFFSET_OVERFLOW; + graph_data->generation = get_be64(g->chunk_generation_data_overflow + 8 * offset_pos); + } else + graph_data->generation = item->date + offset; + } else + graph_data->generation = get_be32(commit_data + g->hash_len + 8) >> 2; if (g->topo_levels) *topo_level_slab_at(g->topo_levels, item) = get_be32(commit_data + g->hash_len + 8) >> 2; @@ -945,6 +975,7 @@ struct write_commit_graph_context { struct oid_array oids; struct packed_commit_list commits; int num_extra_edges; + int num_generation_data_overflows; unsigned long approx_nr_objects; struct progress *progress; int progress_done; @@ -963,7 +994,8 @@ struct write_commit_graph_context { report_progress:1, split:1, changed_paths:1, - order_by_pack:1; + order_by_pack:1, + write_generation_data:1; struct topo_level_slab *topo_levels; const struct commit_graph_opts *opts; @@ -1123,6 +1155,45 @@ static int write_graph_chunk_data(struct hashfile *f, return 0; } +static int write_graph_chunk_generation_data(struct hashfile *f, + struct write_commit_graph_context *ctx) +{ + int i, num_generation_data_overflows = 0; + + for (i = 0; i < ctx->commits.nr; i++) { + struct commit *c = ctx->commits.list[i]; + timestamp_t offset = commit_graph_data_at(c)->generation - c->date; + display_progress(ctx->progress, ++ctx->progress_cnt); + + if (offset > GENERATION_NUMBER_V2_OFFSET_MAX) { + offset = CORRECTED_COMMIT_DATE_OFFSET_OVERFLOW | num_generation_data_overflows; + num_generation_data_overflows++; + } + + hashwrite_be32(f, offset); + } + + return 0; +} + +static int write_graph_chunk_generation_data_overflow(struct hashfile *f, + struct write_commit_graph_context *ctx) +{ + int i; + for (i = 0; i < ctx->commits.nr; i++) { + struct commit *c = ctx->commits.list[i]; + timestamp_t offset = commit_graph_data_at(c)->generation - c->date; + display_progress(ctx->progress, ++ctx->progress_cnt); + + if (offset > GENERATION_NUMBER_V2_OFFSET_MAX) { + hashwrite_be32(f, offset >> 32); + hashwrite_be32(f, (uint32_t) offset); + } + } + + return 0; +} + static int write_graph_chunk_extra_edges(struct hashfile *f, struct write_commit_graph_context *ctx) { @@ -1386,6 +1457,9 @@ static void compute_generation_numbers(struct write_commit_graph_context *ctx) if (current->date && current->date > max_corrected_commit_date) max_corrected_commit_date = current->date - 1; commit_graph_data_at(current)->generation = max_corrected_commit_date + 1; + + if (commit_graph_data_at(current)->generation - current->date > GENERATION_NUMBER_V2_OFFSET_MAX) + ctx->num_generation_data_overflows++; } } } @@ -1719,6 +1793,21 @@ static int write_commit_graph_file(struct write_commit_graph_context *ctx) chunks[2].id = GRAPH_CHUNKID_DATA; chunks[2].size = (hashsz + 16) * ctx->commits.nr; chunks[2].write_fn = write_graph_chunk_data; + + if (git_env_bool(GIT_TEST_COMMIT_GRAPH_NO_GDAT, 0)) + ctx->write_generation_data = 0; + if (ctx->write_generation_data) { + chunks[num_chunks].id = GRAPH_CHUNKID_GENERATION_DATA; + chunks[num_chunks].size = sizeof(uint32_t) * ctx->commits.nr; + chunks[num_chunks].write_fn = write_graph_chunk_generation_data; + num_chunks++; + } + if (ctx->num_generation_data_overflows) { + chunks[num_chunks].id = GRAPH_CHUNKID_GENERATION_DATA_OVERFLOW; + chunks[num_chunks].size = sizeof(timestamp_t) * ctx->num_generation_data_overflows; + chunks[num_chunks].write_fn = write_graph_chunk_generation_data_overflow; + num_chunks++; + } if (ctx->num_extra_edges) { chunks[num_chunks].id = GRAPH_CHUNKID_EXTRAEDGES; chunks[num_chunks].size = 4 * ctx->num_extra_edges; @@ -2139,6 +2228,8 @@ int write_commit_graph(struct object_directory *odb, ctx->split = flags & COMMIT_GRAPH_WRITE_SPLIT ? 1 : 0; ctx->opts = opts; ctx->total_bloom_filter_data_size = 0; + ctx->write_generation_data = 1; + ctx->num_generation_data_overflows = 0; bloom_settings.bits_per_entry = git_env_ulong("GIT_TEST_BLOOM_SETTINGS_BITS_PER_ENTRY", bloom_settings.bits_per_entry); @@ -2445,16 +2536,17 @@ int verify_commit_graph(struct repository *r, struct commit_graph *g, int flags) continue; /* - * If one of our parents has generation GENERATION_NUMBER_V1_MAX, then - * our generation is also GENERATION_NUMBER_V1_MAX. Decrement to avoid - * extra logic in the following condition. + * If we are using topological level and one of our parents has + * generation GENERATION_NUMBER_V1_MAX, then our generation is + * also GENERATION_NUMBER_V1_MAX. Decrement to avoid extra logic + * in the following condition. */ - if (max_generation == GENERATION_NUMBER_V1_MAX) + if (!g->chunk_generation_data && max_generation == GENERATION_NUMBER_V1_MAX) max_generation--; generation = commit_graph_generation(graph_commit); - if (generation != max_generation + 1) - graph_report(_("commit-graph generation for commit %s is %"PRItime" != %"PRItime), + if (generation < max_generation + 1) + graph_report(_("commit-graph generation for commit %s is %"PRItime" < %"PRItime), oid_to_hex(&cur_oid), generation, max_generation + 1); diff --git a/commit-graph.h b/commit-graph.h index 2e9aa7824e..19a02001fd 100644 --- a/commit-graph.h +++ b/commit-graph.h @@ -6,6 +6,7 @@ #include "oidset.h" #define GIT_TEST_COMMIT_GRAPH "GIT_TEST_COMMIT_GRAPH" +#define GIT_TEST_COMMIT_GRAPH_NO_GDAT "GIT_TEST_COMMIT_GRAPH_NO_GDAT" #define GIT_TEST_COMMIT_GRAPH_DIE_ON_PARSE "GIT_TEST_COMMIT_GRAPH_DIE_ON_PARSE" #define GIT_TEST_COMMIT_GRAPH_CHANGED_PATHS "GIT_TEST_COMMIT_GRAPH_CHANGED_PATHS" @@ -68,6 +69,8 @@ struct commit_graph { const uint32_t *chunk_oid_fanout; const unsigned char *chunk_oid_lookup; const unsigned char *chunk_commit_data; + const unsigned char *chunk_generation_data; + const unsigned char *chunk_generation_data_overflow; const unsigned char *chunk_extra_edges; const unsigned char *chunk_base_graphs; const unsigned char *chunk_bloom_indexes; diff --git a/commit.h b/commit.h index 33c66b2177..251d877fcf 100644 --- a/commit.h +++ b/commit.h @@ -14,6 +14,7 @@ #define GENERATION_NUMBER_INFINITY ((1ULL << 63) - 1) #define GENERATION_NUMBER_V1_MAX 0x3FFFFFFF #define GENERATION_NUMBER_ZERO 0 +#define GENERATION_NUMBER_V2_OFFSET_MAX ((1ULL << 31) - 1) struct commit_list { struct commit *item; diff --git a/t/README b/t/README index c730a70770..8a12148727 100644 --- a/t/README +++ b/t/README @@ -393,6 +393,9 @@ GIT_TEST_COMMIT_GRAPH=, when true, forces the commit-graph to be written after every 'git commit' command, and overrides the 'core.commitGraph' setting to true. +GIT_TEST_COMMIT_GRAPH_NO_GDAT=, when true, forces the +commit-graph to be written without generation data chunk. + GIT_TEST_COMMIT_GRAPH_CHANGED_PATHS=, when true, forces commit-graph write to compute and write changed path Bloom filters for every 'git commit-graph write', as if the `--changed-paths` option was diff --git a/t/helper/test-read-graph.c b/t/helper/test-read-graph.c index 5f585a1725..75927b2c81 100644 --- a/t/helper/test-read-graph.c +++ b/t/helper/test-read-graph.c @@ -33,6 +33,10 @@ int cmd__read_graph(int argc, const char **argv) printf(" oid_lookup"); if (graph->chunk_commit_data) printf(" commit_metadata"); + if (graph->chunk_generation_data) + printf(" generation_data"); + if (graph->chunk_generation_data_overflow) + printf(" generation_data_overflow"); if (graph->chunk_extra_edges) printf(" extra_edges"); if (graph->chunk_bloom_indexes) diff --git a/t/t4216-log-bloom.sh b/t/t4216-log-bloom.sh index d11040ce41..dbde016188 100755 --- a/t/t4216-log-bloom.sh +++ b/t/t4216-log-bloom.sh @@ -40,11 +40,11 @@ test_expect_success 'setup test - repo, commits, commit graph, log outputs' ' ' graph_read_expect () { - NUM_CHUNKS=5 + NUM_CHUNKS=6 cat >expect <<- EOF header: 43475048 1 $(test_oid oid_version) $NUM_CHUNKS 0 num_commits: $1 - chunks: oid_fanout oid_lookup commit_metadata bloom_indexes bloom_data + chunks: oid_fanout oid_lookup commit_metadata generation_data bloom_indexes bloom_data EOF test-tool read-graph >actual && test_cmp expect actual diff --git a/t/t5318-commit-graph.sh b/t/t5318-commit-graph.sh index 2ed0c1544d..fa27df579a 100755 --- a/t/t5318-commit-graph.sh +++ b/t/t5318-commit-graph.sh @@ -76,7 +76,7 @@ graph_git_behavior 'no graph' full commits/3 commits/1 graph_read_expect() { OPTIONAL="" NUM_CHUNKS=3 - if test ! -z $2 + if test ! -z "$2" then OPTIONAL=" $2" NUM_CHUNKS=$((3 + $(echo "$2" | wc -w))) @@ -103,14 +103,14 @@ test_expect_success 'exit with correct error on bad input to --stdin-commits' ' # valid commit and tree OID git rev-parse HEAD HEAD^{tree} >in && git commit-graph write --stdin-commits >commits-in && cat commits-in | git commit-graph write --stdin-commits && test_path_is_file $objdir/info/commit-graph && - graph_read_expect "6" + graph_read_expect "6" "generation_data" ' graph_git_behavior 'graph from commits, commit 8 vs merge 1' full commits/8 merge/1 @@ -297,7 +297,7 @@ test_expect_success 'build graph from commits with append' ' cd "$TRASH_DIRECTORY/full" && git rev-parse merge/3 | git commit-graph write --stdin-commits --append && test_path_is_file $objdir/info/commit-graph && - graph_read_expect "10" "extra_edges" + graph_read_expect "10" "generation_data extra_edges" ' graph_git_behavior 'append graph, commit 8 vs merge 1' full commits/8 merge/1 @@ -307,7 +307,7 @@ test_expect_success 'build graph using --reachable' ' cd "$TRASH_DIRECTORY/full" && git commit-graph write --reachable && test_path_is_file $objdir/info/commit-graph && - graph_read_expect "11" "extra_edges" + graph_read_expect "11" "generation_data extra_edges" ' graph_git_behavior 'append graph, commit 8 vs merge 1' full commits/8 merge/1 @@ -328,7 +328,7 @@ test_expect_success 'write graph in bare repo' ' cd "$TRASH_DIRECTORY/bare" && git commit-graph write && test_path_is_file $baredir/info/commit-graph && - graph_read_expect "11" "extra_edges" + graph_read_expect "11" "generation_data extra_edges" ' graph_git_behavior 'bare repo with graph, commit 8 vs merge 1' bare commits/8 merge/1 @@ -454,8 +454,9 @@ test_expect_success 'warn on improper hash version' ' test_expect_success 'git commit-graph verify' ' cd "$TRASH_DIRECTORY/full" && - git rev-parse commits/8 | git commit-graph write --stdin-commits && - git commit-graph verify >output + git rev-parse commits/8 | GIT_TEST_COMMIT_GRAPH_NO_GDAT=1 git commit-graph write --stdin-commits && + git commit-graph verify >output && + graph_read_expect 9 extra_edges ' NUM_COMMITS=9 @@ -741,4 +742,56 @@ test_expect_success 'corrupt commit-graph write (missing tree)' ' ) ' +# We test the overflow-related code with the following repo history: +# +# 4:F - 5:N - 6:U +# / \ +# 1:U - 2:N - 3:U M:N +# \ / +# 7:N - 8:F - 9:N +# +# Here the commits denoted by U have committer date of zero seconds +# since Unix epoch, the commits denoted by N have committer date +# starting from 1112354055 seconds since Unix epoch (default committer +# date for the test suite), and the commits denoted by F have committer +# date of (2 ^ 31 - 2) seconds since Unix epoch. +# +# The largest offset observed is 2 ^ 31, just large enough to overflow. +# + +test_expect_success 'set up and verify repo with generation data overflow chunk' ' + objdir=".git/objects" && + UNIX_EPOCH_ZERO="@0 +0000" && + FUTURE_DATE="@2147483646 +0000" && + test_oid_cache <<-EOF && + oid_version sha1:1 + oid_version sha256:2 + EOF + cd "$TRASH_DIRECTORY" && + mkdir repo && + cd repo && + git init && + test_commit --date "$UNIX_EPOCH_ZERO" 1 && + test_commit 2 && + test_commit --date "$UNIX_EPOCH_ZERO" 3 && + git commit-graph write --reachable && + graph_read_expect 3 generation_data && + test_commit --date "$FUTURE_DATE" 4 && + test_commit 5 && + test_commit --date "$UNIX_EPOCH_ZERO" 6 && + git branch left && + git reset --hard 3 && + test_commit 7 && + test_commit --date "$FUTURE_DATE" 8 && + test_commit 9 && + git branch right && + git reset --hard 3 && + test_merge M left right && + git commit-graph write --reachable && + graph_read_expect 10 "generation_data generation_data_overflow" && + git commit-graph verify +' + +graph_git_behavior 'generation data overflow chunk repo' repo left right + test_done diff --git a/t/t5324-split-commit-graph.sh b/t/t5324-split-commit-graph.sh index 4d3842b83b..587757b62d 100755 --- a/t/t5324-split-commit-graph.sh +++ b/t/t5324-split-commit-graph.sh @@ -13,11 +13,11 @@ test_expect_success 'setup repo' ' infodir=".git/objects/info" && graphdir="$infodir/commit-graphs" && test_oid_cache <<-EOM - shallow sha1:1760 - shallow sha256:2064 + shallow sha1:2132 + shallow sha256:2436 - base sha1:1376 - base sha256:1496 + base sha1:1408 + base sha256:1528 oid_version sha1:1 oid_version sha256:2 @@ -31,9 +31,9 @@ graph_read_expect() { NUM_BASE=$2 fi cat >expect <<- EOF - header: 43475048 1 $(test_oid oid_version) 3 $NUM_BASE + header: 43475048 1 $(test_oid oid_version) 4 $NUM_BASE num_commits: $1 - chunks: oid_fanout oid_lookup commit_metadata + chunks: oid_fanout oid_lookup commit_metadata generation_data EOF test-tool read-graph >output && test_cmp expect output diff --git a/t/t6600-test-reach.sh b/t/t6600-test-reach.sh index af10f0dc09..e2d33a8a4c 100755 --- a/t/t6600-test-reach.sh +++ b/t/t6600-test-reach.sh @@ -55,6 +55,9 @@ test_expect_success 'setup' ' git show-ref -s commit-5-5 | git commit-graph write --stdin-commits && mv .git/objects/info/commit-graph commit-graph-half && chmod u+w commit-graph-half && + GIT_TEST_COMMIT_GRAPH_NO_GDAT=1 git commit-graph write --reachable && + mv .git/objects/info/commit-graph commit-graph-no-gdat && + chmod u+w commit-graph-no-gdat && git config core.commitGraph true ' @@ -67,6 +70,9 @@ run_all_modes () { test_cmp expect actual && cp commit-graph-half .git/objects/info/commit-graph && "$@" actual && + test_cmp expect actual && + cp commit-graph-no-gdat .git/objects/info/commit-graph && + "$@" actual && test_cmp expect actual } diff --git a/t/test-lib-functions.sh b/t/test-lib-functions.sh index 999982fe4a..3ad712c3ac 100644 --- a/t/test-lib-functions.sh +++ b/t/test-lib-functions.sh @@ -202,6 +202,12 @@ test_commit () { --signoff) signoff="$1" ;; + --date) + notick=yes + GIT_COMMITTER_DATE="$2" + GIT_AUTHOR_DATE="$2" + shift + ;; -C) indir="$2" shift