odb: introduce parent pointers

In subsequent commits we'll get rid of our use of `the_repository` in
"odb.c" in favor of explicitly passing in a `struct object_database` or
a `struct odb_source`. In some cases though we'll need access to the
repository, for example to read a config value from it, but we don't
have a way to access the repository owning a specific object database.

Introduce parent pointers for `struct object_database` to its owning
repository as well as for `struct odb_source` to its owning object
database, which will allow us to adapt those use cases.

Note that this change requires us to pass through the object database to
`link_alt_odb_entry()` so that we can set up the parent pointers for any
source there. The callchain is adapted to pass through the object
database accordingly.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/odb.c b/odb.c
index d1025ac182d15110b8a7fd1fe2700d0451211b2b..afb16f4c693e85cc55d5fe2ee1169a9f6e744be8 100644 (file)
--- a/odb.c
+++ b/odb.c
@@ -135,11 +135,15 @@ static int alt_odb_usable(struct object_database *o,
  * of the object ID, an extra slash for the first level indirection, and
  * the terminating NUL.
  */
-static void read_info_alternates(struct repository *r,
+static void read_info_alternates(struct object_database *odb,
                                 const char *relative_base,
                                 int depth);
-static int link_alt_odb_entry(struct repository *r, const struct strbuf *entry,
-       const char *relative_base, int depth, const char *normalized_objdir)
+
+static int link_alt_odb_entry(struct object_database *odb,
+                             const struct strbuf *entry,
+                             const char *relative_base,
+                             int depth,
+                             const char *normalized_objdir)
 {
        struct odb_source *alternate;
        struct strbuf pathbuf = STRBUF_INIT;
@@ -167,22 +171,23 @@ static int link_alt_odb_entry(struct repository *r, const struct strbuf *entry,
        while (pathbuf.len && pathbuf.buf[pathbuf.len - 1] == '/')
                strbuf_setlen(&pathbuf, pathbuf.len - 1);
 
-       if (!alt_odb_usable(r->objects, &pathbuf, normalized_objdir, &pos))
+       if (!alt_odb_usable(odb, &pathbuf, normalized_objdir, &pos))
                goto error;
 
        CALLOC_ARRAY(alternate, 1);
-       /* pathbuf.buf is already in r->objects->source_by_path */
+       alternate->odb = odb;
+       /* pathbuf.buf is already in r->objects->alternate_by_path */
        alternate->path = strbuf_detach(&pathbuf, NULL);
 
        /* add the alternate entry */
-       *r->objects->sources_tail = alternate;
-       r->objects->sources_tail = &(alternate->next);
+       *odb->sources_tail = alternate;
+       odb->sources_tail = &(alternate->next);
        alternate->next = NULL;
-       assert(r->objects->source_by_path);
-       kh_value(r->objects->source_by_path, pos) = alternate;
+       assert(odb->source_by_path);
+       kh_value(odb->source_by_path, pos) = alternate;
 
        /* recursively add alternates */
-       read_info_alternates(r, alternate->path, depth + 1);
+       read_info_alternates(odb, alternate->path, depth + 1);
        ret = 0;
  error:
        strbuf_release(&tmp);
@@ -219,7 +224,7 @@ static const char *parse_alt_odb_entry(const char *string,
        return end;
 }
 
-static void link_alt_odb_entries(struct repository *r, const char *alt,
+static void link_alt_odb_entries(struct object_database *odb, const char *alt,
                                 int sep, const char *relative_base, int depth)
 {
        struct strbuf objdirbuf = STRBUF_INIT;
@@ -234,20 +239,20 @@ static void link_alt_odb_entries(struct repository *r, const char *alt,
                return;
        }
 
-       strbuf_realpath(&objdirbuf, r->objects->sources->path, 1);
+       strbuf_realpath(&objdirbuf, odb->sources->path, 1);
 
        while (*alt) {
                alt = parse_alt_odb_entry(alt, sep, &entry);
                if (!entry.len)
                        continue;
-               link_alt_odb_entry(r, &entry,
+               link_alt_odb_entry(odb, &entry,
                                   relative_base, depth, objdirbuf.buf);
        }
        strbuf_release(&entry);
        strbuf_release(&objdirbuf);
 }
 
-static void read_info_alternates(struct repository *r,
+static void read_info_alternates(struct object_database *odb,
                                 const char *relative_base,
                                 int depth)
 {
@@ -261,7 +266,7 @@ static void read_info_alternates(struct repository *r,
                return;
        }
 
-       link_alt_odb_entries(r, buf.buf, '\n', relative_base, depth);
+       link_alt_odb_entries(odb, buf.buf, '\n', relative_base, depth);
        strbuf_release(&buf);
        free(path);
 }
@@ -303,7 +308,7 @@ void add_to_alternates_file(const char *reference)
                if (commit_lock_file(&lock))
                        die_errno(_("unable to move new alternates file into place"));
                if (the_repository->objects->loaded_alternates)
-                       link_alt_odb_entries(the_repository, reference,
+                       link_alt_odb_entries(the_repository->objects, reference,
                                             '\n', NULL, 0);
        }
        free(alts);
@@ -317,7 +322,7 @@ void add_to_alternates_memory(const char *reference)
         */
        prepare_alt_odb(the_repository);
 
-       link_alt_odb_entries(the_repository, reference,
+       link_alt_odb_entries(the_repository->objects, reference,
                             '\n', NULL, 0);
 }
 
@@ -336,6 +341,7 @@ struct odb_source *set_temporary_primary_odb(const char *dir, int will_destroy)
         * alternate
         */
        source = xcalloc(1, sizeof(*source));
+       source->odb = the_repository->objects;
        source->path = xstrdup(dir);
 
        /*
@@ -580,9 +586,9 @@ void prepare_alt_odb(struct repository *r)
        if (r->objects->loaded_alternates)
                return;
 
-       link_alt_odb_entries(r, r->objects->alternate_db, PATH_SEP, NULL, 0);
+       link_alt_odb_entries(r->objects, r->objects->alternate_db, PATH_SEP, NULL, 0);
 
-       read_info_alternates(r, r->objects->sources->path, 0);
+       read_info_alternates(r->objects, r->objects->sources->path, 0);
        r->objects->loaded_alternates = 1;
 }
 
@@ -950,11 +956,12 @@ void assert_oid_type(const struct object_id *oid, enum object_type expect)
                    type_name(expect));
 }
 
-struct object_database *odb_new(void)
+struct object_database *odb_new(struct repository *repo)
 {
        struct object_database *o = xmalloc(sizeof(*o));
 
        memset(o, 0, sizeof(*o));
+       o->repo = repo;
        INIT_LIST_HEAD(&o->packed_git_mru);
        hashmap_init(&o->pack_map, pack_map_entry_cmp, NULL, 0);
        pthread_mutex_init(&o->replace_mutex, NULL);

diff --git a/odb.h b/odb.h
index 6f56b168e4665ea19009462f2e8ffa17047a3957..c3851e296685cb28ffd86114ca6d07a40515ccb4 100644 (file)
--- a/odb.h
+++ b/odb.h
@@ -28,6 +28,9 @@ struct repository;
 struct odb_source {
        struct odb_source *next;
 
+       /* Object database that owns this object source. */
+       struct object_database *odb;
+
        /*
         * Used to store the results of readdir(3) calls when we are OK
         * sacrificing accuracy due to races for speed. That includes
@@ -105,6 +108,9 @@ struct cached_object_entry;
  * configured via alternates.
  */
 struct object_database {
+       /* Repository that owns this database. */
+       struct repository *repo;
+
        /*
         * Set of all object directories; the main directory is first (and
         * cannot be NULL after initialization). Subsequent directories are
@@ -186,7 +192,7 @@ struct object_database {
        unsigned packed_git_initialized : 1;
 };
 
-struct object_database *odb_new(void);
+struct object_database *odb_new(struct repository *repo);
 void odb_clear(struct object_database *o);
 
 /*

diff --git a/repository.c b/repository.c
index 13426db0f2be268e282d6bf8276018673635f7f5..c606e1153c8b46d89f299ad249f1b5e73ab5b78c 100644 (file)
--- a/repository.c
+++ b/repository.c
@@ -52,7 +52,7 @@ static void set_default_hash_algo(struct repository *repo)
 
 void initialize_repository(struct repository *repo)
 {
-       repo->objects = odb_new();
+       repo->objects = odb_new(repo);
        repo->remote_state = remote_state_new();
        repo->parsed_objects = parsed_object_pool_new(repo);
        ALLOC_ARRAY(repo->index, 1);
@@ -167,6 +167,7 @@ void repo_set_gitdir(struct repository *repo,
 
        if (!repo->objects->sources) {
                CALLOC_ARRAY(repo->objects->sources, 1);
+               repo->objects->sources->odb = repo->objects;
                repo->objects->sources_tail = &repo->objects->sources->next;
        }
        expand_base_dir(&repo->objects->sources->path, o->object_dir,