diff options
Diffstat (limited to 'src/commit_graph.c')
| -rw-r--r-- | src/commit_graph.c | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/src/commit_graph.c b/src/commit_graph.c index 71a56e3da..9740418e2 100644 --- a/src/commit_graph.c +++ b/src/commit_graph.c @@ -9,6 +9,7 @@ #include "futils.h" #include "hash.h" +#include "pack.h" #define GIT_COMMIT_GRAPH_MISSING_PARENT 0x70000000 @@ -278,6 +279,142 @@ int git_commit_graph_open(git_commit_graph_file **cgraph_out, const char *path) return 0; } +static int git_commit_graph_entry_get_byindex( + git_commit_graph_entry *e, + const git_commit_graph_file *cgraph, + size_t pos) +{ + const unsigned char *commit_data; + + GIT_ASSERT_ARG(e); + GIT_ASSERT_ARG(cgraph); + + if (pos >= cgraph->num_commits) { + git_error_set(GIT_ERROR_INVALID, "commit index %zu does not exist", pos); + return GIT_ENOTFOUND; + } + + commit_data = cgraph->commit_data + pos * (GIT_OID_RAWSZ + 4 * sizeof(uint32_t)); + git_oid_cpy(&e->tree_oid, (const git_oid *)commit_data); + e->parent_indices[0] = ntohl(*((uint32_t *)(commit_data + GIT_OID_RAWSZ))); + e->parent_indices[1] + = ntohl(*((uint32_t *)(commit_data + GIT_OID_RAWSZ + sizeof(uint32_t)))); + e->parent_count = (e->parent_indices[0] != GIT_COMMIT_GRAPH_MISSING_PARENT) + + (e->parent_indices[1] != GIT_COMMIT_GRAPH_MISSING_PARENT); + e->generation = ntohl(*((uint32_t *)(commit_data + GIT_OID_RAWSZ + 2 * sizeof(uint32_t)))); + e->commit_time = ntohl(*((uint32_t *)(commit_data + GIT_OID_RAWSZ + 3 * sizeof(uint32_t)))); + + e->commit_time |= (e->generation & 0x3ull) << 32ull; + e->generation >>= 2u; + if (e->parent_indices[1] & 0x80000000u) { + uint32_t extra_edge_list_pos = e->parent_indices[1] & 0x7fffffff; + + /* Make sure we're not being sent out of bounds */ + if (extra_edge_list_pos >= cgraph->num_extra_edge_list) { + git_error_set(GIT_ERROR_INVALID, + "commit %u does not exist", + extra_edge_list_pos); + return GIT_ENOTFOUND; + } + + e->extra_parents_index = extra_edge_list_pos; + while (extra_edge_list_pos < cgraph->num_extra_edge_list + && (ntohl(*( + (uint32_t *)(cgraph->extra_edge_list + + extra_edge_list_pos * sizeof(uint32_t)))) + & 0x80000000u) + == 0) { + extra_edge_list_pos++; + e->parent_count++; + } + + } + git_oid_cpy(&e->sha1, &cgraph->oid_lookup[pos]); + return 0; +} + +int git_commit_graph_entry_find( + git_commit_graph_entry *e, + const git_commit_graph_file *cgraph, + const git_oid *short_oid, + size_t len) +{ + int pos, found = 0; + uint32_t hi, lo; + const git_oid *current = NULL; + + GIT_ASSERT_ARG(e); + GIT_ASSERT_ARG(cgraph); + GIT_ASSERT_ARG(short_oid); + + hi = ntohl(cgraph->oid_fanout[(int)short_oid->id[0]]); + lo = ((short_oid->id[0] == 0x0) ? 0 : ntohl(cgraph->oid_fanout[(int)short_oid->id[0] - 1])); + + pos = git_pack__lookup_sha1(cgraph->oid_lookup, GIT_OID_RAWSZ, lo, hi, short_oid->id); + + if (pos >= 0) { + /* An object matching exactly the oid was found */ + found = 1; + current = cgraph->oid_lookup + pos; + } else { + /* No object was found */ + /* pos refers to the object with the "closest" oid to short_oid */ + pos = -1 - pos; + if (pos < (int)cgraph->num_commits) { + current = cgraph->oid_lookup + pos; + + if (!git_oid_ncmp(short_oid, current, len)) + found = 1; + } + } + + if (found && len != GIT_OID_HEXSZ && pos + 1 < (int)cgraph->num_commits) { + /* Check for ambiguousity */ + const git_oid *next = current + 1; + + if (!git_oid_ncmp(short_oid, next, len)) { + found = 2; + } + } + + if (!found) + return git_odb__error_notfound( + "failed to find offset for multi-pack index entry", short_oid, len); + if (found > 1) + return git_odb__error_ambiguous( + "found multiple offsets for multi-pack index entry"); + + return git_commit_graph_entry_get_byindex(e, cgraph, pos); +} + +int git_commit_graph_entry_parent( + git_commit_graph_entry *parent, + const git_commit_graph_file *cgraph, + const git_commit_graph_entry *entry, + size_t n) +{ + GIT_ASSERT_ARG(parent); + GIT_ASSERT_ARG(cgraph); + + if (n >= entry->parent_count) { + git_error_set(GIT_ERROR_INVALID, "parent index %zu does not exist", n); + return GIT_ENOTFOUND; + } + + if (n == 0 || (n == 1 && entry->parent_count == 2)) + return git_commit_graph_entry_get_byindex(parent, cgraph, entry->parent_indices[n]); + + return git_commit_graph_entry_get_byindex( + parent, + cgraph, + ntohl( + *(uint32_t *)(cgraph->extra_edge_list + + (entry->extra_parents_index + n - 1) + * sizeof(uint32_t))) + & 0x7fffffff); +} + + int git_commit_graph_close(git_commit_graph_file *cgraph) { GIT_ASSERT_ARG(cgraph); |