#include "revision.h"
#include "sha1-lookup.h"
#include "commit-graph.h"
+#include "object-store.h"
#define GRAPH_SIGNATURE 0x43475048 /* "CGPH" */
#define GRAPH_CHUNKID_OIDFANOUT 0x4f494446 /* "OIDF" */
#define GRAPH_MIN_SIZE (5 * GRAPH_CHUNKLOOKUP_WIDTH + GRAPH_FANOUT_SIZE + \
GRAPH_OID_LEN + 8)
-
-static char *get_commit_graph_filename(const char *obj_dir)
+char *get_commit_graph_filename(const char *obj_dir)
{
return xstrfmt("%s/info/commit-graph", obj_dir);
}
+static struct commit_graph *alloc_commit_graph(void)
+{
+ struct commit_graph *g = xcalloc(1, sizeof(*g));
+ g->graph_fd = -1;
+
+ return g;
+}
+
+struct commit_graph *load_commit_graph_one(const char *graph_file)
+{
+ void *graph_map;
+ const unsigned char *data, *chunk_lookup;
+ size_t graph_size;
+ struct stat st;
+ uint32_t i;
+ struct commit_graph *graph;
+ int fd = git_open(graph_file);
+ uint64_t last_chunk_offset;
+ uint32_t last_chunk_id;
+ uint32_t graph_signature;
+ unsigned char graph_version, hash_version;
+
+ if (fd < 0)
+ return NULL;
+ if (fstat(fd, &st)) {
+ close(fd);
+ return NULL;
+ }
+ graph_size = xsize_t(st.st_size);
+
+ if (graph_size < GRAPH_MIN_SIZE) {
+ close(fd);
+ die("graph file %s is too small", graph_file);
+ }
+ graph_map = xmmap(NULL, graph_size, PROT_READ, MAP_PRIVATE, fd, 0);
+ data = (const unsigned char *)graph_map;
+
+ graph_signature = get_be32(data);
+ if (graph_signature != GRAPH_SIGNATURE) {
+ error("graph signature %X does not match signature %X",
+ graph_signature, GRAPH_SIGNATURE);
+ goto cleanup_fail;
+ }
+
+ graph_version = *(unsigned char*)(data + 4);
+ if (graph_version != GRAPH_VERSION) {
+ error("graph version %X does not match version %X",
+ graph_version, GRAPH_VERSION);
+ goto cleanup_fail;
+ }
+
+ hash_version = *(unsigned char*)(data + 5);
+ if (hash_version != GRAPH_OID_VERSION) {
+ error("hash version %X does not match version %X",
+ hash_version, GRAPH_OID_VERSION);
+ goto cleanup_fail;
+ }
+
+ graph = alloc_commit_graph();
+
+ graph->hash_len = GRAPH_OID_LEN;
+ graph->num_chunks = *(unsigned char*)(data + 6);
+ graph->graph_fd = fd;
+ graph->data = graph_map;
+ graph->data_len = graph_size;
+
+ last_chunk_id = 0;
+ last_chunk_offset = 8;
+ chunk_lookup = data + 8;
+ for (i = 0; i < graph->num_chunks; i++) {
+ uint32_t chunk_id = get_be32(chunk_lookup + 0);
+ uint64_t chunk_offset = get_be64(chunk_lookup + 4);
+ int chunk_repeated = 0;
+
+ chunk_lookup += GRAPH_CHUNKLOOKUP_WIDTH;
+
+ if (chunk_offset > graph_size - GIT_MAX_RAWSZ) {
+ error("improper chunk offset %08x%08x", (uint32_t)(chunk_offset >> 32),
+ (uint32_t)chunk_offset);
+ goto cleanup_fail;
+ }
+
+ switch (chunk_id) {
+ case GRAPH_CHUNKID_OIDFANOUT:
+ if (graph->chunk_oid_fanout)
+ chunk_repeated = 1;
+ else
+ graph->chunk_oid_fanout = (uint32_t*)(data + chunk_offset);
+ break;
+
+ case GRAPH_CHUNKID_OIDLOOKUP:
+ if (graph->chunk_oid_lookup)
+ chunk_repeated = 1;
+ else
+ graph->chunk_oid_lookup = data + chunk_offset;
+ break;
+
+ case GRAPH_CHUNKID_DATA:
+ if (graph->chunk_commit_data)
+ chunk_repeated = 1;
+ else
+ graph->chunk_commit_data = data + chunk_offset;
+ break;
+
+ case GRAPH_CHUNKID_LARGEEDGES:
+ if (graph->chunk_large_edges)
+ chunk_repeated = 1;
+ else
+ graph->chunk_large_edges = data + chunk_offset;
+ break;
+ }
+
+ if (chunk_repeated) {
+ error("chunk id %08x appears multiple times", chunk_id);
+ goto cleanup_fail;
+ }
+
+ if (last_chunk_id == GRAPH_CHUNKID_OIDLOOKUP)
+ {
+ graph->num_commits = (chunk_offset - last_chunk_offset)
+ / graph->hash_len;
+ }
+
+ last_chunk_id = chunk_id;
+ last_chunk_offset = chunk_offset;
+ }
+
+ return graph;
+
+cleanup_fail:
+ munmap(graph_map, graph_size);
+ close(fd);
+ exit(1);
+}
+
+/* global storage */
+static struct commit_graph *commit_graph = NULL;
+
+static void prepare_commit_graph_one(const char *obj_dir)
+{
+ char *graph_name;
+
+ if (commit_graph)
+ return;
+
+ graph_name = get_commit_graph_filename(obj_dir);
+ commit_graph = load_commit_graph_one(graph_name);
+
+ FREE_AND_NULL(graph_name);
+}
+
+static int prepare_commit_graph_run_once = 0;
+static void prepare_commit_graph(void)
+{
+ struct alternate_object_database *alt;
+ char *obj_dir;
+
+ if (prepare_commit_graph_run_once)
+ return;
+ prepare_commit_graph_run_once = 1;
+
+ obj_dir = get_object_directory();
+ prepare_commit_graph_one(obj_dir);
+ prepare_alt_odb(the_repository);
+ for (alt = the_repository->objects->alt_odb_list;
+ !commit_graph && alt;
+ alt = alt->next)
+ prepare_commit_graph_one(alt->path);
+}
+
+static void close_commit_graph(void)
+{
+ if (!commit_graph)
+ return;
+
+ if (commit_graph->graph_fd >= 0) {
+ munmap((void *)commit_graph->data, commit_graph->data_len);
+ commit_graph->data = NULL;
+ close(commit_graph->graph_fd);
+ }
+
+ FREE_AND_NULL(commit_graph);
+}
+
+static int bsearch_graph(struct commit_graph *g, struct object_id *oid, uint32_t *pos)
+{
+ return bsearch_hash(oid->hash, g->chunk_oid_fanout,
+ g->chunk_oid_lookup, g->hash_len, pos);
+}
+
+static struct commit_list **insert_parent_or_die(struct commit_graph *g,
+ uint64_t pos,
+ struct commit_list **pptr)
+{
+ struct commit *c;
+ struct object_id oid;
+ hashcpy(oid.hash, g->chunk_oid_lookup + g->hash_len * pos);
+ c = lookup_commit(&oid);
+ if (!c)
+ die("could not find commit %s", oid_to_hex(&oid));
+ c->graph_pos = pos;
+ return &commit_list_insert(c, pptr)->next;
+}
+
+static int fill_commit_in_graph(struct commit *item, struct commit_graph *g, uint32_t pos)
+{
+ struct object_id oid;
+ uint32_t edge_value;
+ uint32_t *parent_data_ptr;
+ uint64_t date_low, date_high;
+ struct commit_list **pptr;
+ const unsigned char *commit_data = g->chunk_commit_data + (g->hash_len + 16) * pos;
+
+ item->object.parsed = 1;
+ item->graph_pos = pos;
+
+ hashcpy(oid.hash, commit_data);
+ item->tree = lookup_tree(&oid);
+
+ date_high = get_be32(commit_data + g->hash_len + 8) & 0x3;
+ date_low = get_be32(commit_data + g->hash_len + 12);
+ item->date = (timestamp_t)((date_high << 32) | date_low);
+
+ pptr = &item->parents;
+
+ edge_value = get_be32(commit_data + g->hash_len);
+ if (edge_value == GRAPH_PARENT_NONE)
+ return 1;
+ pptr = insert_parent_or_die(g, edge_value, pptr);
+
+ edge_value = get_be32(commit_data + g->hash_len + 4);
+ if (edge_value == GRAPH_PARENT_NONE)
+ return 1;
+ if (!(edge_value & GRAPH_OCTOPUS_EDGES_NEEDED)) {
+ pptr = insert_parent_or_die(g, edge_value, pptr);
+ return 1;
+ }
+
+ parent_data_ptr = (uint32_t*)(g->chunk_large_edges +
+ 4 * (uint64_t)(edge_value & GRAPH_EDGE_LAST_MASK));
+ do {
+ edge_value = get_be32(parent_data_ptr);
+ pptr = insert_parent_or_die(g,
+ edge_value & GRAPH_EDGE_LAST_MASK,
+ pptr);
+ parent_data_ptr++;
+ } while (!(edge_value & GRAPH_LAST_EDGE));
+
+ return 1;
+}
+
+int parse_commit_in_graph(struct commit *item)
+{
+ if (!core_commit_graph)
+ return 0;
+ if (item->object.parsed)
+ return 1;
+
+ prepare_commit_graph();
+ if (commit_graph) {
+ uint32_t pos;
+ int found;
+ if (item->graph_pos != COMMIT_NOT_FROM_GRAPH) {
+ pos = item->graph_pos;
+ found = 1;
+ } else {
+ found = bsearch_graph(commit_graph, &(item->object.oid), &pos);
+ }
+
+ if (found)
+ return fill_commit_in_graph(item, commit_graph, pos);
+ }
+
+ return 0;
+}
+
static void write_graph_chunk_fanout(struct hashfile *f,
struct commit **commits,
int nr_commits)
return 0;
}
-void write_commit_graph(const char *obj_dir)
+static void add_missing_parents(struct packed_oid_list *oids, struct commit *commit)
+{
+ struct commit_list *parent;
+ for (parent = commit->parents; parent; parent = parent->next) {
+ if (!(parent->item->object.flags & UNINTERESTING)) {
+ ALLOC_GROW(oids->list, oids->nr + 1, oids->alloc);
+ oidcpy(&oids->list[oids->nr], &(parent->item->object.oid));
+ oids->nr++;
+ parent->item->object.flags |= UNINTERESTING;
+ }
+ }
+}
+
+static void close_reachable(struct packed_oid_list *oids)
+{
+ int i;
+ struct commit *commit;
+
+ for (i = 0; i < oids->nr; i++) {
+ commit = lookup_commit(&oids->list[i]);
+ if (commit)
+ commit->object.flags |= UNINTERESTING;
+ }
+
+ /*
+ * As this loop runs, oids->nr may grow, but not more
+ * than the number of missing commits in the reachable
+ * closure.
+ */
+ for (i = 0; i < oids->nr; i++) {
+ commit = lookup_commit(&oids->list[i]);
+
+ if (commit && !parse_commit(commit))
+ add_missing_parents(oids, commit);
+ }
+
+ for (i = 0; i < oids->nr; i++) {
+ commit = lookup_commit(&oids->list[i]);
+
+ if (commit)
+ commit->object.flags &= ~UNINTERESTING;
+ }
+}
+
+void write_commit_graph(const char *obj_dir,
+ const char **pack_indexes,
+ int nr_packs,
+ const char **commit_hex,
+ int nr_commits,
+ int append)
{
struct packed_oid_list oids;
struct packed_commit_list commits;
oids.nr = 0;
oids.alloc = approximate_object_count() / 4;
+ if (append) {
+ prepare_commit_graph_one(obj_dir);
+ if (commit_graph)
+ oids.alloc += commit_graph->num_commits;
+ }
+
if (oids.alloc < 1024)
oids.alloc = 1024;
ALLOC_ARRAY(oids.list, oids.alloc);
- for_each_packed_object(add_packed_commits, &oids, 0);
+ if (append && commit_graph) {
+ for (i = 0; i < commit_graph->num_commits; i++) {
+ const unsigned char *hash = commit_graph->chunk_oid_lookup +
+ commit_graph->hash_len * i;
+ hashcpy(oids.list[oids.nr++].hash, hash);
+ }
+ }
+
+ if (pack_indexes) {
+ struct strbuf packname = STRBUF_INIT;
+ int dirlen;
+ strbuf_addf(&packname, "%s/pack/", obj_dir);
+ dirlen = packname.len;
+ for (i = 0; i < nr_packs; i++) {
+ struct packed_git *p;
+ strbuf_setlen(&packname, dirlen);
+ strbuf_addstr(&packname, pack_indexes[i]);
+ p = add_packed_git(packname.buf, packname.len, 1);
+ if (!p)
+ die("error adding pack %s", packname.buf);
+ if (open_pack_index(p))
+ die("error opening index for %s", packname.buf);
+ for_each_object_in_pack(p, add_packed_commits, &oids);
+ close_pack(p);
+ }
+ strbuf_release(&packname);
+ }
+
+ if (commit_hex) {
+ for (i = 0; i < nr_commits; i++) {
+ const char *end;
+ struct object_id oid;
+ struct commit *result;
+
+ if (commit_hex[i] && parse_oid_hex(commit_hex[i], &oid, &end))
+ continue;
+
+ result = lookup_commit_reference_gently(&oid, 1);
+
+ if (result) {
+ ALLOC_GROW(oids.list, oids.nr + 1, oids.alloc);
+ oidcpy(&oids.list[oids.nr], &(result->object.oid));
+ oids.nr++;
+ }
+ }
+ }
+
+ if (!pack_indexes && !commit_hex)
+ for_each_packed_object(add_packed_commits, &oids, 0);
+
+ close_reachable(&oids);
QSORT(oids.list, oids.nr, commit_compare);
write_graph_chunk_data(f, GRAPH_OID_LEN, commits.list, commits.nr);
write_graph_chunk_large_edges(f, commits.list, commits.nr);
+ close_commit_graph();
finalize_hashfile(f, NULL, CSUM_HASH_IN_STREAM | CSUM_FSYNC);
commit_lock_file(&lk);