Submodule ref backend that mirrors superproject

index bb531e0e5..ce511180e 100644
@@ -1977,16 +1977,24 @@ void absorb_git_dir_into_superproject(const char *prefix,
 	}
 }
 
-const char *get_superproject_working_tree(void)
+/*
+ * Get the full filename of the gitlink entry corresponding to the
+ * superproject having this repo as a submodule.
+ *
+ * full_name will point to an internal buffer upon success.
+ *
+ * Return 0 if successful, 1 if not (for example, if the parent
+ * directory is not a repo or an unrelated one).
+ */
+int get_superproject_entry(const char **full_name)
 {
+	static struct strbuf sb = STRBUF_INIT;
+
 	struct child_process cp = CHILD_PROCESS_INIT;
-	struct strbuf sb = STRBUF_INIT;
 	const char *one_up = real_path_if_valid("../");
 	const char *cwd = xgetcwd();
-	const char *ret = NULL;
 	const char *subpath;
 	int code;
-	ssize_t len;
 
 	if (!is_inside_work_tree())
 		/*

@@ -1994,11 +2002,15 @@ const char *get_superproject_working_tree(void)
 		 * We might have a superproject, but it is harder
 		 * to determine.
 		 */
-		return NULL;
+		return 1;
 
 	if (!one_up)
-		return NULL;
+		return 1;
 
+	/*
+	 * No need to reset sb, since relative_path() will do it if
+	 * necessary.
+	 */
 	subpath = relative_path(cwd, one_up, &sb);
 
 	prepare_submodule_repo_env(&cp.env_array);

@@ -2017,45 +2029,49 @@ const char *get_superproject_working_tree(void)
 	if (start_command(&cp))
 		die(_("could not start ls-files in .."));
 
-	len = strbuf_read(&sb, cp.out, PATH_MAX);
+	strbuf_read(&sb, cp.out, PATH_MAX);
 	close(cp.out);
 
-	if (starts_with(sb.buf, "160000")) {
-		int super_sub_len;
-		int cwd_len = strlen(cwd);
-		char *super_sub, *super_wt;
+	code = finish_command(&cp);
 
+	if (starts_with(sb.buf, "160000")) {
 		/*
 		 * There is a superproject having this repo as a submodule.
 		 * The format is <mode> SP <hash> SP <stage> TAB <full name> \0,
 		 * We're only interested in the name after the tab.
 		 */
-		super_sub = strchr(sb.buf, '\t') + 1;
-		super_sub_len = sb.buf + sb.len - super_sub - 1;
-
-		if (super_sub_len > cwd_len ||
-		    strcmp(&cwd[cwd_len - super_sub_len], super_sub))
-			die (_("BUG: returned path string doesn't match cwd?"));
-
-		super_wt = xstrdup(cwd);
-		super_wt[cwd_len - super_sub_len] = '\0';
-
-		ret = real_path(super_wt);
-		free(super_wt);
+		char *tab = strchr(sb.buf, '\t');
+		if (!tab)
+			die("BUG: ls-files returned line with no tab");
+		*full_name = tab + 1;
+		return 0;
 	}
-	strbuf_release(&sb);
-
-	code = finish_command(&cp);
 
 	if (code == 128)
 		/* '../' is not a git repository */
-		return NULL;
-	if (code == 0 && len == 0)
+		return 1;
+	if (code == 0)
 		/* There is an unrelated git repository at '../' */
+		return 1;
+	die(_("ls-tree returned unexpected return code %d"), code);
+}
+
+const char *get_superproject_working_tree(void)
+{
+	const char *full_name;
+	char *super_wt;
+	size_t len;
+	const char *ret;
+
+	if (get_superproject_entry(&full_name))
 		return NULL;
-	if (code)
-		die(_("ls-tree returned unexpected return code %d"), code);
 
+	super_wt = xstrdup(xgetcwd());
+	if (!strip_suffix(super_wt, full_name, &len))
+		die("BUG: returned path string doesn't match cwd?");
+	super_wt[len] = '\0';
+	ret = real_path(super_wt);
+	free(super_wt);
 	return ret;
 }
 

index f0da0277a..29ab302cc 100644
@@ -134,6 +134,9 @@ extern void absorb_git_dir_into_superproject(const char *prefix,
  * Return the absolute path of the working tree of the superproject, which this
  * project is a submodule of. If this repository is not a submodule of
  * another repository, return NULL.
+ *
+ * The return value, if not NULL, points to the same shared buffer as the one
+ * returned by real_path().
  */
 extern const char *get_superproject_working_tree(void);
 

index 339d4318e..1f7922733 100644
@@ -1575,12 +1575,17 @@ static struct ref_store *lookup_ref_store_map(struct hashmap *map,
 static struct ref_store *ref_store_init(const char *gitdir,
 					unsigned int flags)
 {
-	const char *be_name = "files";
-	struct ref_storage_be *be = find_ref_storage_backend(be_name);
+	struct ref_storage_be *be;
 	struct ref_store *refs;
 
+	if (getenv("USE_SP")) {
+		be = &refs_be_sp;
+	} else {
+		be = &refs_be_files;
+	}
+
 	if (!be)
-		die("BUG: reference backend %s is unknown", be_name);
+		die("BUG: reference backend %s is unknown", "files");
 
 	refs = be->init(gitdir, flags);
 	return refs;

index dd834314b..a8ec03d90 100644
@@ -651,6 +651,7 @@ struct ref_storage_be {
 
 extern struct ref_storage_be refs_be_files;
 extern struct ref_storage_be refs_be_packed;
+extern struct ref_storage_be refs_be_sp;
 
 /*
  * A representation of the reference store for the main repository or

261 lines not on this page · raw message

80 lines not on this page · raw message

index 29ab302cc..3a836beab 100644
@@ -140,4 +140,6 @@ extern void absorb_git_dir_into_superproject(const char *prefix,
  */
 extern const char *get_superproject_working_tree(void);
 
+extern int get_superproject_gitlink_oid(const char *ref, struct object_id *oid);
+
 #endif