git/commit-graph.c
Junio C Hamano 6d8f8ebb74 Merge branch 'ds/commit-graph-with-grafts'
The recently introduced commit-graph auxiliary data is incompatible
with mechanisms such as replace & grafts that "breaks" immutable
nature of the object reference relationship.  Disable optimizations
based on its use (and updating existing commit-graph) when these
incompatible features are in use in the repository.

* ds/commit-graph-with-grafts:
  commit-graph: close_commit_graph before shallow walk
  commit-graph: not compatible with uninitialized repo
  commit-graph: not compatible with grafts
  commit-graph: not compatible with replace objects
  test-repository: properly init repo
  commit-graph: update design document
  refs.c: upgrade for_each_replace_ref to be a each_repo_ref_fn callback
  refs.c: migrate internal ref iteration to pass thru repository argument
2018-10-16 16:15:59 +09:00

1142 lines
30 KiB
C

#include "cache.h"
#include "config.h"
#include "dir.h"
#include "git-compat-util.h"
#include "lockfile.h"
#include "pack.h"
#include "packfile.h"
#include "commit.h"
#include "object.h"
#include "refs.h"
#include "revision.h"
#include "sha1-lookup.h"
#include "commit-graph.h"
#include "object-store.h"
#include "alloc.h"
#include "hashmap.h"
#include "replace-object.h"
#include "progress.h"
#define GRAPH_SIGNATURE 0x43475048 /* "CGPH" */
#define GRAPH_CHUNKID_OIDFANOUT 0x4f494446 /* "OIDF" */
#define GRAPH_CHUNKID_OIDLOOKUP 0x4f49444c /* "OIDL" */
#define GRAPH_CHUNKID_DATA 0x43444154 /* "CDAT" */
#define GRAPH_CHUNKID_LARGEEDGES 0x45444745 /* "EDGE" */
#define GRAPH_DATA_WIDTH 36
#define GRAPH_VERSION_1 0x1
#define GRAPH_VERSION GRAPH_VERSION_1
#define GRAPH_OID_VERSION_SHA1 1
#define GRAPH_OID_LEN_SHA1 GIT_SHA1_RAWSZ
#define GRAPH_OID_VERSION GRAPH_OID_VERSION_SHA1
#define GRAPH_OID_LEN GRAPH_OID_LEN_SHA1
#define GRAPH_OCTOPUS_EDGES_NEEDED 0x80000000
#define GRAPH_PARENT_MISSING 0x7fffffff
#define GRAPH_EDGE_LAST_MASK 0x7fffffff
#define GRAPH_PARENT_NONE 0x70000000
#define GRAPH_LAST_EDGE 0x80000000
#define GRAPH_HEADER_SIZE 8
#define GRAPH_FANOUT_SIZE (4 * 256)
#define GRAPH_CHUNKLOOKUP_WIDTH 12
#define GRAPH_MIN_SIZE (GRAPH_HEADER_SIZE + 4 * GRAPH_CHUNKLOOKUP_WIDTH \
+ GRAPH_FANOUT_SIZE + GRAPH_OID_LEN)
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;
}
extern int read_replace_refs;
static int commit_graph_compatible(struct repository *r)
{
if (!r->gitdir)
return 0;
if (read_replace_refs) {
prepare_replace_object(r);
if (hashmap_get_size(&r->objects->replace_map->map))
return 0;
}
prepare_commit_graft(r);
if (r->parsed_objects && r->parsed_objects->grafts_nr)
return 0;
if (is_repository_shallow(r))
return 0;
return 1;
}
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);
}
static void prepare_commit_graph_one(struct repository *r, const char *obj_dir)
{
char *graph_name;
if (r->objects->commit_graph)
return;
graph_name = get_commit_graph_filename(obj_dir);
r->objects->commit_graph =
load_commit_graph_one(graph_name);
FREE_AND_NULL(graph_name);
}
/*
* Return 1 if commit_graph is non-NULL, and 0 otherwise.
*
* On the first invocation, this function attemps to load the commit
* graph if the_repository is configured to have one.
*/
static int prepare_commit_graph(struct repository *r)
{
struct alternate_object_database *alt;
char *obj_dir;
int config_value;
if (r->objects->commit_graph_attempted)
return !!r->objects->commit_graph;
r->objects->commit_graph_attempted = 1;
if (!git_env_bool(GIT_TEST_COMMIT_GRAPH, 0) &&
(repo_config_get_bool(r, "core.commitgraph", &config_value) ||
!config_value))
/*
* This repository is not configured to use commit graphs, so
* do not load one. (But report commit_graph_attempted anyway
* so that commit graph loading is not attempted again for this
* repository.)
*/
return 0;
if (!commit_graph_compatible(r))
return 0;
obj_dir = r->objects->objectdir;
prepare_commit_graph_one(r, obj_dir);
prepare_alt_odb(r);
for (alt = r->objects->alt_odb_list;
!r->objects->commit_graph && alt;
alt = alt->next)
prepare_commit_graph_one(r, alt->path);
return !!r->objects->commit_graph;
}
int generation_numbers_enabled(struct repository *r)
{
uint32_t first_generation;
struct commit_graph *g;
if (!prepare_commit_graph(r))
return 0;
g = r->objects->commit_graph;
if (!g->num_commits)
return 0;
first_generation = get_be32(g->chunk_commit_data +
g->hash_len + 8) >> 2;
return !!first_generation;
}
void close_commit_graph(struct repository *r)
{
free_commit_graph(r->objects->commit_graph);
r->objects->commit_graph = NULL;
}
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;
if (pos >= g->num_commits)
die("invalid parent position %"PRIu64, pos);
hashcpy(oid.hash, g->chunk_oid_lookup + g->hash_len * pos);
c = lookup_commit(the_repository, &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 void fill_commit_graph_info(struct commit *item, struct commit_graph *g, uint32_t pos)
{
const unsigned char *commit_data = g->chunk_commit_data + GRAPH_DATA_WIDTH * pos;
item->graph_pos = pos;
item->generation = get_be32(commit_data + g->hash_len + 8) >> 2;
}
static int fill_commit_in_graph(struct commit *item, struct commit_graph *g, uint32_t pos)
{
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;
item->maybe_tree = NULL;
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);
item->generation = get_be32(commit_data + g->hash_len + 8) >> 2;
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;
}
static int find_commit_in_graph(struct commit *item, struct commit_graph *g, uint32_t *pos)
{
if (item->graph_pos != COMMIT_NOT_FROM_GRAPH) {
*pos = item->graph_pos;
return 1;
} else {
return bsearch_graph(g, &(item->object.oid), pos);
}
}
static int parse_commit_in_graph_one(struct commit_graph *g, struct commit *item)
{
uint32_t pos;
if (item->object.parsed)
return 1;
if (find_commit_in_graph(item, g, &pos))
return fill_commit_in_graph(item, g, pos);
return 0;
}
int parse_commit_in_graph(struct repository *r, struct commit *item)
{
if (!prepare_commit_graph(r))
return 0;
return parse_commit_in_graph_one(r->objects->commit_graph, item);
}
void load_commit_graph_info(struct repository *r, struct commit *item)
{
uint32_t pos;
if (!prepare_commit_graph(r))
return;
if (find_commit_in_graph(item, r->objects->commit_graph, &pos))
fill_commit_graph_info(item, r->objects->commit_graph, pos);
}
static struct tree *load_tree_for_commit(struct commit_graph *g, struct commit *c)
{
struct object_id oid;
const unsigned char *commit_data = g->chunk_commit_data +
GRAPH_DATA_WIDTH * (c->graph_pos);
hashcpy(oid.hash, commit_data);
c->maybe_tree = lookup_tree(the_repository, &oid);
return c->maybe_tree;
}
static struct tree *get_commit_tree_in_graph_one(struct commit_graph *g,
const struct commit *c)
{
if (c->maybe_tree)
return c->maybe_tree;
if (c->graph_pos == COMMIT_NOT_FROM_GRAPH)
BUG("get_commit_tree_in_graph_one called from non-commit-graph commit");
return load_tree_for_commit(g, (struct commit *)c);
}
struct tree *get_commit_tree_in_graph(struct repository *r, const struct commit *c)
{
return get_commit_tree_in_graph_one(r->objects->commit_graph, c);
}
static void write_graph_chunk_fanout(struct hashfile *f,
struct commit **commits,
int nr_commits)
{
int i, count = 0;
struct commit **list = commits;
/*
* Write the first-level table (the list is sorted,
* but we use a 256-entry lookup to be able to avoid
* having to do eight extra binary search iterations).
*/
for (i = 0; i < 256; i++) {
while (count < nr_commits) {
if ((*list)->object.oid.hash[0] != i)
break;
count++;
list++;
}
hashwrite_be32(f, count);
}
}
static void write_graph_chunk_oids(struct hashfile *f, int hash_len,
struct commit **commits, int nr_commits)
{
struct commit **list = commits;
int count;
for (count = 0; count < nr_commits; count++, list++)
hashwrite(f, (*list)->object.oid.hash, (int)hash_len);
}
static const unsigned char *commit_to_sha1(size_t index, void *table)
{
struct commit **commits = table;
return commits[index]->object.oid.hash;
}
static void write_graph_chunk_data(struct hashfile *f, int hash_len,
struct commit **commits, int nr_commits)
{
struct commit **list = commits;
struct commit **last = commits + nr_commits;
uint32_t num_extra_edges = 0;
while (list < last) {
struct commit_list *parent;
int edge_value;
uint32_t packedDate[2];
parse_commit(*list);
hashwrite(f, get_commit_tree_oid(*list)->hash, hash_len);
parent = (*list)->parents;
if (!parent)
edge_value = GRAPH_PARENT_NONE;
else {
edge_value = sha1_pos(parent->item->object.oid.hash,
commits,
nr_commits,
commit_to_sha1);
if (edge_value < 0)
edge_value = GRAPH_PARENT_MISSING;
}
hashwrite_be32(f, edge_value);
if (parent)
parent = parent->next;
if (!parent)
edge_value = GRAPH_PARENT_NONE;
else if (parent->next)
edge_value = GRAPH_OCTOPUS_EDGES_NEEDED | num_extra_edges;
else {
edge_value = sha1_pos(parent->item->object.oid.hash,
commits,
nr_commits,
commit_to_sha1);
if (edge_value < 0)
edge_value = GRAPH_PARENT_MISSING;
}
hashwrite_be32(f, edge_value);
if (edge_value & GRAPH_OCTOPUS_EDGES_NEEDED) {
do {
num_extra_edges++;
parent = parent->next;
} while (parent);
}
if (sizeof((*list)->date) > 4)
packedDate[0] = htonl(((*list)->date >> 32) & 0x3);
else
packedDate[0] = 0;
packedDate[0] |= htonl((*list)->generation << 2);
packedDate[1] = htonl((*list)->date);
hashwrite(f, packedDate, 8);
list++;
}
}
static void write_graph_chunk_large_edges(struct hashfile *f,
struct commit **commits,
int nr_commits)
{
struct commit **list = commits;
struct commit **last = commits + nr_commits;
struct commit_list *parent;
while (list < last) {
int num_parents = 0;
for (parent = (*list)->parents; num_parents < 3 && parent;
parent = parent->next)
num_parents++;
if (num_parents <= 2) {
list++;
continue;
}
/* Since num_parents > 2, this initializer is safe. */
for (parent = (*list)->parents->next; parent; parent = parent->next) {
int edge_value = sha1_pos(parent->item->object.oid.hash,
commits,
nr_commits,
commit_to_sha1);
if (edge_value < 0)
edge_value = GRAPH_PARENT_MISSING;
else if (!parent->next)
edge_value |= GRAPH_LAST_EDGE;
hashwrite_be32(f, edge_value);
}
list++;
}
}
static int commit_compare(const void *_a, const void *_b)
{
const struct object_id *a = (const struct object_id *)_a;
const struct object_id *b = (const struct object_id *)_b;
return oidcmp(a, b);
}
struct packed_commit_list {
struct commit **list;
int nr;
int alloc;
};
struct packed_oid_list {
struct object_id *list;
int nr;
int alloc;
struct progress *progress;
int progress_done;
};
static int add_packed_commits(const struct object_id *oid,
struct packed_git *pack,
uint32_t pos,
void *data)
{
struct packed_oid_list *list = (struct packed_oid_list*)data;
enum object_type type;
off_t offset = nth_packed_object_offset(pack, pos);
struct object_info oi = OBJECT_INFO_INIT;
if (list->progress)
display_progress(list->progress, ++list->progress_done);
oi.typep = &type;
if (packed_object_info(the_repository, pack, offset, &oi) < 0)
die(_("unable to get type of object %s"), oid_to_hex(oid));
if (type != OBJ_COMMIT)
return 0;
ALLOC_GROW(list->list, list->nr + 1, list->alloc);
oidcpy(&(list->list[list->nr]), oid);
list->nr++;
return 0;
}
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 report_progress)
{
int i;
struct commit *commit;
struct progress *progress = NULL;
int j = 0;
if (report_progress)
progress = start_delayed_progress(
_("Annotating commits in commit graph"), 0);
for (i = 0; i < oids->nr; i++) {
display_progress(progress, ++j);
commit = lookup_commit(the_repository, &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++) {
display_progress(progress, ++j);
commit = lookup_commit(the_repository, &oids->list[i]);
if (commit && !parse_commit(commit))
add_missing_parents(oids, commit);
}
for (i = 0; i < oids->nr; i++) {
display_progress(progress, ++j);
commit = lookup_commit(the_repository, &oids->list[i]);
if (commit)
commit->object.flags &= ~UNINTERESTING;
}
stop_progress(&progress);
}
static void compute_generation_numbers(struct packed_commit_list* commits,
int report_progress)
{
int i;
struct commit_list *list = NULL;
struct progress *progress = NULL;
if (report_progress)
progress = start_progress(
_("Computing commit graph generation numbers"),
commits->nr);
for (i = 0; i < commits->nr; i++) {
display_progress(progress, i + 1);
if (commits->list[i]->generation != GENERATION_NUMBER_INFINITY &&
commits->list[i]->generation != GENERATION_NUMBER_ZERO)
continue;
commit_list_insert(commits->list[i], &list);
while (list) {
struct commit *current = list->item;
struct commit_list *parent;
int all_parents_computed = 1;
uint32_t max_generation = 0;
for (parent = current->parents; parent; parent = parent->next) {
if (parent->item->generation == GENERATION_NUMBER_INFINITY ||
parent->item->generation == GENERATION_NUMBER_ZERO) {
all_parents_computed = 0;
commit_list_insert(parent->item, &list);
break;
} else if (parent->item->generation > max_generation) {
max_generation = parent->item->generation;
}
}
if (all_parents_computed) {
current->generation = max_generation + 1;
pop_commit(&list);
if (current->generation > GENERATION_NUMBER_MAX)
current->generation = GENERATION_NUMBER_MAX;
}
}
}
stop_progress(&progress);
}
static int add_ref_to_list(const char *refname,
const struct object_id *oid,
int flags, void *cb_data)
{
struct string_list *list = (struct string_list *)cb_data;
string_list_append(list, oid_to_hex(oid));
return 0;
}
void write_commit_graph_reachable(const char *obj_dir, int append,
int report_progress)
{
struct string_list list;
string_list_init(&list, 1);
for_each_ref(add_ref_to_list, &list);
write_commit_graph(obj_dir, NULL, &list, append, report_progress);
}
void write_commit_graph(const char *obj_dir,
struct string_list *pack_indexes,
struct string_list *commit_hex,
int append, int report_progress)
{
struct packed_oid_list oids;
struct packed_commit_list commits;
struct hashfile *f;
uint32_t i, count_distinct = 0;
char *graph_name;
struct lock_file lk = LOCK_INIT;
uint32_t chunk_ids[5];
uint64_t chunk_offsets[5];
int num_chunks;
int num_extra_edges;
struct commit_list *parent;
struct progress *progress = NULL;
if (!commit_graph_compatible(the_repository))
return;
oids.nr = 0;
oids.alloc = approximate_object_count() / 4;
oids.progress = NULL;
oids.progress_done = 0;
if (append) {
prepare_commit_graph_one(the_repository, obj_dir);
if (the_repository->objects->commit_graph)
oids.alloc += the_repository->objects->commit_graph->num_commits;
}
if (oids.alloc < 1024)
oids.alloc = 1024;
ALLOC_ARRAY(oids.list, oids.alloc);
if (append && the_repository->objects->commit_graph) {
struct commit_graph *commit_graph =
the_repository->objects->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;
if (report_progress) {
oids.progress = start_delayed_progress(
_("Finding commits for commit graph"), 0);
oids.progress_done = 0;
}
for (i = 0; i < pack_indexes->nr; i++) {
struct packed_git *p;
strbuf_setlen(&packname, dirlen);
strbuf_addstr(&packname, pack_indexes->items[i].string);
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, 0);
close_pack(p);
}
stop_progress(&oids.progress);
strbuf_release(&packname);
}
if (commit_hex) {
if (report_progress)
progress = start_delayed_progress(
_("Finding commits for commit graph"),
commit_hex->nr);
for (i = 0; i < commit_hex->nr; i++) {
const char *end;
struct object_id oid;
struct commit *result;
display_progress(progress, i + 1);
if (commit_hex->items[i].string &&
parse_oid_hex(commit_hex->items[i].string, &oid, &end))
continue;
result = lookup_commit_reference_gently(the_repository, &oid, 1);
if (result) {
ALLOC_GROW(oids.list, oids.nr + 1, oids.alloc);
oidcpy(&oids.list[oids.nr], &(result->object.oid));
oids.nr++;
}
}
stop_progress(&progress);
}
if (!pack_indexes && !commit_hex) {
if (report_progress)
oids.progress = start_delayed_progress(
_("Finding commits for commit graph"), 0);
for_each_packed_object(add_packed_commits, &oids, 0);
stop_progress(&oids.progress);
}
close_reachable(&oids, report_progress);
QSORT(oids.list, oids.nr, commit_compare);
count_distinct = 1;
for (i = 1; i < oids.nr; i++) {
if (!oideq(&oids.list[i - 1], &oids.list[i]))
count_distinct++;
}
if (count_distinct >= GRAPH_PARENT_MISSING)
die(_("the commit graph format cannot write %d commits"), count_distinct);
commits.nr = 0;
commits.alloc = count_distinct;
ALLOC_ARRAY(commits.list, commits.alloc);
num_extra_edges = 0;
for (i = 0; i < oids.nr; i++) {
int num_parents = 0;
if (i > 0 && oideq(&oids.list[i - 1], &oids.list[i]))
continue;
commits.list[commits.nr] = lookup_commit(the_repository, &oids.list[i]);
parse_commit(commits.list[commits.nr]);
for (parent = commits.list[commits.nr]->parents;
parent; parent = parent->next)
num_parents++;
if (num_parents > 2)
num_extra_edges += num_parents - 1;
commits.nr++;
}
num_chunks = num_extra_edges ? 4 : 3;
if (commits.nr >= GRAPH_PARENT_MISSING)
die(_("too many commits to write graph"));
compute_generation_numbers(&commits, report_progress);
graph_name = get_commit_graph_filename(obj_dir);
if (safe_create_leading_directories(graph_name))
die_errno(_("unable to create leading directories of %s"),
graph_name);
hold_lock_file_for_update(&lk, graph_name, LOCK_DIE_ON_ERROR);
f = hashfd(lk.tempfile->fd, lk.tempfile->filename.buf);
hashwrite_be32(f, GRAPH_SIGNATURE);
hashwrite_u8(f, GRAPH_VERSION);
hashwrite_u8(f, GRAPH_OID_VERSION);
hashwrite_u8(f, num_chunks);
hashwrite_u8(f, 0); /* unused padding byte */
chunk_ids[0] = GRAPH_CHUNKID_OIDFANOUT;
chunk_ids[1] = GRAPH_CHUNKID_OIDLOOKUP;
chunk_ids[2] = GRAPH_CHUNKID_DATA;
if (num_extra_edges)
chunk_ids[3] = GRAPH_CHUNKID_LARGEEDGES;
else
chunk_ids[3] = 0;
chunk_ids[4] = 0;
chunk_offsets[0] = 8 + (num_chunks + 1) * GRAPH_CHUNKLOOKUP_WIDTH;
chunk_offsets[1] = chunk_offsets[0] + GRAPH_FANOUT_SIZE;
chunk_offsets[2] = chunk_offsets[1] + GRAPH_OID_LEN * commits.nr;
chunk_offsets[3] = chunk_offsets[2] + (GRAPH_OID_LEN + 16) * commits.nr;
chunk_offsets[4] = chunk_offsets[3] + 4 * num_extra_edges;
for (i = 0; i <= num_chunks; i++) {
uint32_t chunk_write[3];
chunk_write[0] = htonl(chunk_ids[i]);
chunk_write[1] = htonl(chunk_offsets[i] >> 32);
chunk_write[2] = htonl(chunk_offsets[i] & 0xffffffff);
hashwrite(f, chunk_write, 12);
}
write_graph_chunk_fanout(f, commits.list, commits.nr);
write_graph_chunk_oids(f, GRAPH_OID_LEN, commits.list, commits.nr);
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(the_repository);
finalize_hashfile(f, NULL, CSUM_HASH_IN_STREAM | CSUM_FSYNC);
commit_lock_file(&lk);
free(oids.list);
oids.alloc = 0;
oids.nr = 0;
}
#define VERIFY_COMMIT_GRAPH_ERROR_HASH 2
static int verify_commit_graph_error;
static void graph_report(const char *fmt, ...)
{
va_list ap;
verify_commit_graph_error = 1;
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
fprintf(stderr, "\n");
va_end(ap);
}
#define GENERATION_ZERO_EXISTS 1
#define GENERATION_NUMBER_EXISTS 2
int verify_commit_graph(struct repository *r, struct commit_graph *g)
{
uint32_t i, cur_fanout_pos = 0;
struct object_id prev_oid, cur_oid, checksum;
int generation_zero = 0;
struct hashfile *f;
int devnull;
struct progress *progress = NULL;
if (!g) {
graph_report("no commit-graph file loaded");
return 1;
}
verify_commit_graph_error = 0;
if (!g->chunk_oid_fanout)
graph_report("commit-graph is missing the OID Fanout chunk");
if (!g->chunk_oid_lookup)
graph_report("commit-graph is missing the OID Lookup chunk");
if (!g->chunk_commit_data)
graph_report("commit-graph is missing the Commit Data chunk");
if (verify_commit_graph_error)
return verify_commit_graph_error;
devnull = open("/dev/null", O_WRONLY);
f = hashfd(devnull, NULL);
hashwrite(f, g->data, g->data_len - g->hash_len);
finalize_hashfile(f, checksum.hash, CSUM_CLOSE);
if (!hasheq(checksum.hash, g->data + g->data_len - g->hash_len)) {
graph_report(_("the commit-graph file has incorrect checksum and is likely corrupt"));
verify_commit_graph_error = VERIFY_COMMIT_GRAPH_ERROR_HASH;
}
for (i = 0; i < g->num_commits; i++) {
struct commit *graph_commit;
hashcpy(cur_oid.hash, g->chunk_oid_lookup + g->hash_len * i);
if (i && oidcmp(&prev_oid, &cur_oid) >= 0)
graph_report("commit-graph has incorrect OID order: %s then %s",
oid_to_hex(&prev_oid),
oid_to_hex(&cur_oid));
oidcpy(&prev_oid, &cur_oid);
while (cur_oid.hash[0] > cur_fanout_pos) {
uint32_t fanout_value = get_be32(g->chunk_oid_fanout + cur_fanout_pos);
if (i != fanout_value)
graph_report("commit-graph has incorrect fanout value: fanout[%d] = %u != %u",
cur_fanout_pos, fanout_value, i);
cur_fanout_pos++;
}
graph_commit = lookup_commit(r, &cur_oid);
if (!parse_commit_in_graph_one(g, graph_commit))
graph_report("failed to parse %s from commit-graph",
oid_to_hex(&cur_oid));
}
while (cur_fanout_pos < 256) {
uint32_t fanout_value = get_be32(g->chunk_oid_fanout + cur_fanout_pos);
if (g->num_commits != fanout_value)
graph_report("commit-graph has incorrect fanout value: fanout[%d] = %u != %u",
cur_fanout_pos, fanout_value, i);
cur_fanout_pos++;
}
if (verify_commit_graph_error & ~VERIFY_COMMIT_GRAPH_ERROR_HASH)
return verify_commit_graph_error;
progress = start_progress(_("Verifying commits in commit graph"),
g->num_commits);
for (i = 0; i < g->num_commits; i++) {
struct commit *graph_commit, *odb_commit;
struct commit_list *graph_parents, *odb_parents;
uint32_t max_generation = 0;
display_progress(progress, i + 1);
hashcpy(cur_oid.hash, g->chunk_oid_lookup + g->hash_len * i);
graph_commit = lookup_commit(r, &cur_oid);
odb_commit = (struct commit *)create_object(r, cur_oid.hash, alloc_commit_node(r));
if (parse_commit_internal(odb_commit, 0, 0)) {
graph_report("failed to parse %s from object database",
oid_to_hex(&cur_oid));
continue;
}
if (!oideq(&get_commit_tree_in_graph_one(g, graph_commit)->object.oid,
get_commit_tree_oid(odb_commit)))
graph_report("root tree OID for commit %s in commit-graph is %s != %s",
oid_to_hex(&cur_oid),
oid_to_hex(get_commit_tree_oid(graph_commit)),
oid_to_hex(get_commit_tree_oid(odb_commit)));
graph_parents = graph_commit->parents;
odb_parents = odb_commit->parents;
while (graph_parents) {
if (odb_parents == NULL) {
graph_report("commit-graph parent list for commit %s is too long",
oid_to_hex(&cur_oid));
break;
}
if (!oideq(&graph_parents->item->object.oid, &odb_parents->item->object.oid))
graph_report("commit-graph parent for %s is %s != %s",
oid_to_hex(&cur_oid),
oid_to_hex(&graph_parents->item->object.oid),
oid_to_hex(&odb_parents->item->object.oid));
if (graph_parents->item->generation > max_generation)
max_generation = graph_parents->item->generation;
graph_parents = graph_parents->next;
odb_parents = odb_parents->next;
}
if (odb_parents != NULL)
graph_report("commit-graph parent list for commit %s terminates early",
oid_to_hex(&cur_oid));
if (!graph_commit->generation) {
if (generation_zero == GENERATION_NUMBER_EXISTS)
graph_report("commit-graph has generation number zero for commit %s, but non-zero elsewhere",
oid_to_hex(&cur_oid));
generation_zero = GENERATION_ZERO_EXISTS;
} else if (generation_zero == GENERATION_ZERO_EXISTS)
graph_report("commit-graph has non-zero generation number for commit %s, but zero elsewhere",
oid_to_hex(&cur_oid));
if (generation_zero == GENERATION_ZERO_EXISTS)
continue;
/*
* If one of our parents has generation GENERATION_NUMBER_MAX, then
* our generation is also GENERATION_NUMBER_MAX. Decrement to avoid
* extra logic in the following condition.
*/
if (max_generation == GENERATION_NUMBER_MAX)
max_generation--;
if (graph_commit->generation != max_generation + 1)
graph_report("commit-graph generation for commit %s is %u != %u",
oid_to_hex(&cur_oid),
graph_commit->generation,
max_generation + 1);
if (graph_commit->date != odb_commit->date)
graph_report("commit date for commit %s in commit-graph is %"PRItime" != %"PRItime,
oid_to_hex(&cur_oid),
graph_commit->date,
odb_commit->date);
}
stop_progress(&progress);
return verify_commit_graph_error;
}
void free_commit_graph(struct commit_graph *g)
{
if (!g)
return;
if (g->graph_fd >= 0) {
munmap((void *)g->data, g->data_len);
g->data = NULL;
close(g->graph_fd);
}
free(g);
}