From: "brian m. carlson" <sandals@xxxxxxxxxxxxxxxxxxxx>
As part of the transition plan, we'd like to add a file in the .git
directory that maps loose objects between SHA-1 and SHA-256. Let's
implement the specification in the transition plan and store this data
on a per-repository basis in struct repository.
****
- split repo_object_map between repo_loose_object_map_oid and
repo_oid_to_algop.
- Verified the loose_map is set in repo_loose_object_map_oid
-- EWB
Signed-off-by: brian m. carlson <sandals@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Eric W. Biederman <ebiederm@xxxxxxxxxxxx>
---
Makefile | 1 +
loose.c | 243 ++++++++++++++++++++++++++++++++++++++++++
loose.h | 20 ++++
object-file-convert.c | 14 ++-
object-store-ll.h | 3 +
object.c | 2 +
repository.c | 6 ++
7 files changed, 288 insertions(+), 1 deletion(-)
create mode 100644 loose.c
create mode 100644 loose.h
diff --git a/Makefile b/Makefile
index f7e824f25cda..3c18664def9a 100644
--- a/Makefile
+++ b/Makefile
@@ -1053,6 +1053,7 @@ LIB_OBJS += list-objects-filter.o
LIB_OBJS += list-objects.o
LIB_OBJS += lockfile.o
LIB_OBJS += log-tree.o
+LIB_OBJS += loose.o
LIB_OBJS += ls-refs.o
LIB_OBJS += mailinfo.o
LIB_OBJS += mailmap.o
diff --git a/loose.c b/loose.c
new file mode 100644
index 000000000000..8ddb7112a541
--- /dev/null
+++ b/loose.c
@@ -0,0 +1,243 @@
+#include "git-compat-util.h"
+#include "hash.h"
+#include "path.h"
+#include "object-store.h"
+#include "hex.h"
+#include "wrapper.h"
+#include "gettext.h"
+#include "loose.h"
+#include "lockfile.h"
+
+static const char *loose_object_header = "# loose-object-idx\n";
+
+static inline int should_use_loose_object_map(struct repository *repo)
+{
+ return repo->compat_hash_algo && repo->gitdir;
+}
+
+void loose_object_map_init(struct loose_object_map **map)
+{
+ struct loose_object_map *m;
+ m = xmalloc(sizeof(**map));
+ m->to_compat = kh_init_oid_map();
+ m->to_storage = kh_init_oid_map();
+ *map = m;
+}
+
+static int insert_oid_pair(kh_oid_map_t *map, const struct object_id *key, const struct object_id *value)
+{
+ khiter_t pos;
+ int ret;
+ struct object_id *stored;
+
+ pos = kh_put_oid_map(map, *key, &ret);
+
+ /* This item already exists in the map. */
+ if (ret == 0)
+ return 0;
+
+ stored = xmalloc(sizeof(*stored));
+ oidcpy(stored, value);
+ kh_value(map, pos) = stored;
+ return 1;
+}
+
+static int load_one_loose_object_map(struct repository *repo, struct object_directory *dir)
+{
+ struct strbuf buf = STRBUF_INIT, path = STRBUF_INIT;
+ FILE *fp;
+
+ if (!dir->loose_map)
+ loose_object_map_init(&dir->loose_map);
+
+ insert_oid_pair(dir->loose_map->to_compat, repo->hash_algo->empty_tree, repo->compat_hash_algo->empty_tree);
+ insert_oid_pair(dir->loose_map->to_storage, repo->compat_hash_algo->empty_tree, repo->hash_algo->empty_tree);
+
+ insert_oid_pair(dir->loose_map->to_compat, repo->hash_algo->empty_blob, repo->compat_hash_algo->empty_blob);
+ insert_oid_pair(dir->loose_map->to_storage, repo->compat_hash_algo->empty_blob, repo->hash_algo->empty_blob);
+
+ insert_oid_pair(dir->loose_map->to_compat, repo->hash_algo->null_oid, repo->compat_hash_algo->null_oid);
+ insert_oid_pair(dir->loose_map->to_storage, repo->compat_hash_algo->null_oid, repo->hash_algo->null_oid);
+
+ strbuf_git_common_path(&path, repo, "objects/loose-object-idx");
+ fp = fopen(path.buf, "rb");
+ if (!fp)
+ return 0;
+
+ errno = 0;
+ if (strbuf_getwholeline(&buf, fp, '\n') || strcmp(buf.buf, loose_object_header))
+ goto err;
+ while (!strbuf_getline_lf(&buf, fp)) {
+ const char *p;
+ struct object_id oid, compat_oid;
+ if (parse_oid_hex_algop(buf.buf, &oid, &p, repo->hash_algo) ||
+ *p++ != ' ' ||
+ parse_oid_hex_algop(p, &compat_oid, &p, repo->compat_hash_algo) ||
+ p != buf.buf + buf.len)
+ goto err;
+ insert_oid_pair(dir->loose_map->to_compat, &oid, &compat_oid);
+ insert_oid_pair(dir->loose_map->to_storage, &compat_oid, &oid);
+ }
+
+ strbuf_release(&buf);
+ strbuf_release(&path);
+ return errno ? -1 : 0;
+err:
+ strbuf_release(&buf);
+ strbuf_release(&path);
+ return -1;
+}
+
+int repo_read_loose_object_map(struct repository *repo)
+{
+ struct object_directory *dir;
+
+ if (!should_use_loose_object_map(repo))
+ return 0;
+
+ prepare_alt_odb(repo);
+
+ for (dir = repo->objects->odb; dir; dir = dir->next) {
+ if (load_one_loose_object_map(repo, dir) < 0) {
+ return -1;
+ }
+ }
+ return 0;
+}
+
+int repo_write_loose_object_map(struct repository *repo)
+{
+ kh_oid_map_t *map = repo->objects->odb->loose_map->to_compat;
+ struct lock_file lock;
+ int fd;
+ khiter_t iter;
+ struct strbuf buf = STRBUF_INIT, path = STRBUF_INIT;
+
+ if (!should_use_loose_object_map(repo))
+ return 0;
+
+ strbuf_git_common_path(&path, repo, "objects/loose-object-idx");
+ fd = hold_lock_file_for_update_timeout(&lock, path.buf, LOCK_DIE_ON_ERROR, -1);
+ iter = kh_begin(map);
+ if (write_in_full(fd, loose_object_header, strlen(loose_object_header)) < 0)
+ goto errout;
+
+ for (; iter != kh_end(map); iter++) {
+ if (kh_exist(map, iter)) {
+ if (oideq(&kh_key(map, iter), the_hash_algo->empty_tree) ||
+ oideq(&kh_key(map, iter), the_hash_algo->empty_blob))
+ continue;
+ strbuf_addf(&buf, "%s %s\n", oid_to_hex(&kh_key(map, iter)), oid_to_hex(kh_value(map, iter)));
+ if (write_in_full(fd, buf.buf, buf.len) < 0)
+ goto errout;
+ strbuf_reset(&buf);
+ }
+ }
+ strbuf_release(&buf);
+ if (commit_lock_file(&lock) < 0) {
+ error_errno(_("could not write loose object index %s"), path.buf);
+ strbuf_release(&path);
+ return -1;
+ }
+ strbuf_release(&path);
+ return 0;
+errout:
+ rollback_lock_file(&lock);
+ strbuf_release(&buf);
+ error_errno(_("failed to write loose object index %s\n"), path.buf);
+ strbuf_release(&path);
+ return -1;
+}
+
+static int write_one_object(struct repository *repo, const struct object_id *oid,
+ const struct object_id *compat_oid)
+{
+ struct lock_file lock;
+ int fd;
+ struct stat st;
+ struct strbuf buf = STRBUF_INIT, path = STRBUF_INIT;
+
+ strbuf_git_common_path(&path, repo, "objects/loose-object-idx");
+ hold_lock_file_for_update_timeout(&lock, path.buf, LOCK_DIE_ON_ERROR, -1);
+
+ fd = open(path.buf, O_WRONLY | O_CREAT | O_APPEND, 0666);
+ if (fd < 0)
+ goto errout;
+ if (fstat(fd, &st) < 0)
+ goto errout;
+ if (!st.st_size && write_in_full(fd, loose_object_header, strlen(loose_object_header)) < 0)
+ goto errout;
+
+ strbuf_addf(&buf, "%s %s\n", oid_to_hex(oid), oid_to_hex(compat_oid));
+ if (write_in_full(fd, buf.buf, buf.len) < 0)
+ goto errout;
+ if (close(fd))
+ goto errout;
+ adjust_shared_perm(path.buf);
+ rollback_lock_file(&lock);
+ strbuf_release(&buf);
+ strbuf_release(&path);
+ return 0;
+errout:
+ error_errno(_("failed to write loose object index %s\n"), path.buf);
+ close(fd);
+ rollback_lock_file(&lock);
+ strbuf_release(&buf);
+ strbuf_release(&path);
+ return -1;
+}
+
+int repo_add_loose_object_map(struct repository *repo, const struct object_id *oid,
+ const struct object_id *compat_oid)
+{
+ int inserted = 0;
+
+ if (!should_use_loose_object_map(repo))
+ return 0;
+
+ inserted |= insert_oid_pair(repo->objects->odb->loose_map->to_compat, oid, compat_oid);
+ inserted |= insert_oid_pair(repo->objects->odb->loose_map->to_storage, compat_oid, oid);
+ if (inserted)
+ return write_one_object(repo, oid, compat_oid);
+ return 0;
+}
+
+int repo_loose_object_map_oid(struct repository *repo, struct object_id *dest,
+ const struct git_hash_algo *to,
+ const struct object_id *src)
+{
+ struct object_directory *dir;
+ kh_oid_map_t *map;
+ khiter_t pos;
+
+ for (dir = repo->objects->odb; dir; dir = dir->next) {
+ struct loose_object_map *loose_map = dir->loose_map;
+ if (!loose_map)
+ continue;
+ map = (to == repo->compat_hash_algo) ?
+ loose_map->to_compat :
+ loose_map->to_storage;
+ pos = kh_get_oid_map(map, *src);
+ if (pos < kh_end(map)) {
+ oidcpy(dest, kh_value(map, pos));
+ return 0;
+ }
+ }
+ return -1;
+}
+
+void loose_object_map_clear(struct loose_object_map **map)
+{
+ struct loose_object_map *m = *map;
+ struct object_id *oid;
+
+ if (!m)
+ return;
+
+ kh_foreach_value(m->to_compat, oid, free(oid));
+ kh_foreach_value(m->to_storage, oid, free(oid));
+ kh_destroy_oid_map(m->to_compat);
+ kh_destroy_oid_map(m->to_storage);
+ free(m);
+ *map = NULL;
+}
diff --git a/loose.h b/loose.h
new file mode 100644
index 000000000000..061c6937aead
--- /dev/null
+++ b/loose.h
@@ -0,0 +1,20 @@
+#ifndef LOOSE_H
+#define LOOSE_H
+
+#include "khash.h"
+
+struct loose_object_map {
+ kh_oid_map_t *to_compat;
+ kh_oid_map_t *to_storage;
+};
+
+void loose_object_map_init(struct loose_object_map **map);
+void loose_object_map_clear(struct loose_object_map **map);
+int repo_loose_object_map_oid(struct repository *repo, struct object_id *dest,
+ const struct git_hash_algo *dest_algo, const struct object_id *src);
+int repo_add_loose_object_map(struct repository *repo, const struct object_id *oid,
+ const struct object_id *compat_oid);
+int repo_read_loose_object_map(struct repository *repo);
+int repo_write_loose_object_map(struct repository *repo);
+
+#endif
diff --git a/object-file-convert.c b/object-file-convert.c
index 9f4d5b354f5f..e7c62434016d 100644
--- a/object-file-convert.c
+++ b/object-file-convert.c
@@ -4,6 +4,7 @@
#include "repository.h"
#include "hash-ll.h"
#include "object.h"
+#include "loose.h"
#include "object-file-convert.h"
int repo_oid_to_algop(struct repository *repo, const struct object_id *src,
@@ -21,7 +22,18 @@ int repo_oid_to_algop(struct repository *repo, const struct object_id *src,
oidcpy(dest, src);
return 0;
}
- return -1;
+ if (repo_loose_object_map_oid(repo, dest, to, src)) {
+ /*
+ * We may have loaded the object map at repo initialization but
+ * another process (perhaps upstream of a pipe from us) may have
+ * written a new object into the map. If the object is missing,
+ * let's reload the map to see if the object has appeared.
+ */
+ repo_read_loose_object_map(repo);
+ if (repo_loose_object_map_oid(repo, dest, to, src))
+ return -1;
+ }
+ return 0;
}
int convert_object_file(struct strbuf *outbuf,
diff --git a/object-store-ll.h b/object-store-ll.h
index 26a3895c821c..bc76d6bec80d 100644
--- a/object-store-ll.h
+++ b/object-store-ll.h
@@ -26,6 +26,9 @@ struct object_directory {
uint32_t loose_objects_subdir_seen[8]; /* 256 bits */
struct oidtree *loose_objects_cache;
+ /* Map between object IDs for loose objects. */
+ struct loose_object_map *loose_map;
+
/*
* This is a temporary object store created by the tmp_objdir
* facility. Disable ref updates since the objects in the store
diff --git a/object.c b/object.c
index 2c61e4c86217..186a0a47c0fb 100644
--- a/object.c
+++ b/object.c
@@ -13,6 +13,7 @@
#include "alloc.h"
#include "packfile.h"
#include "commit-graph.h"
+#include "loose.h"
unsigned int get_max_object_index(void)
{
@@ -540,6 +541,7 @@ void free_object_directory(struct object_directory *odb)
{
free(odb->path);
odb_clear_loose_cache(odb);
+ loose_object_map_clear(&odb->loose_map);
free(odb);
}
diff --git a/repository.c b/repository.c
index de620d82bfc6..4ab44d3b0344 100644
--- a/repository.c
+++ b/repository.c
@@ -14,6 +14,7 @@
#include "read-cache-ll.h"
#include "remote.h"
#include "setup.h"
+#include "loose.h"
#include "submodule-config.h"
#include "sparse-index.h"
#include "trace2.h"
@@ -112,6 +113,8 @@ void repo_enable_compat_map(struct repository *repo, int enable_compat)
GIT_HASH_SHA1];
repo->compat_hash_algo = enable_compat ? other_algo : NULL;
+ if (enable_compat)
+ repo_read_loose_object_map(repo);
}
/*
@@ -204,6 +207,9 @@ int repo_init(struct repository *repo,
if (worktree)
repo_set_worktree(repo, worktree);
+ if (repo->compat_hash_algo)
+ repo_read_loose_object_map(repo);
+
clear_repository_format(&format);
return 0;
--
2.41.0
