Merge branch 'bw/repo-object'

Introduce a "repository" object to eventually make it easier to
work in multiple repositories (the primary focus is to work with
the superproject and its submodules) in a single process.

* bw/repo-object:
  ls-files: use repository object
  repository: enable initialization of submodules
  submodule: convert is_submodule_initialized to work on a repository
  submodule: add repo_read_gitmodules
  submodule-config: store the_submodule_cache in the_repository
  repository: add index_state to struct repo
  config: read config from a repository object
  path: add repo_worktree_path and strbuf_repo_worktree_path
  path: add repo_git_path and strbuf_repo_git_path
  path: worktree_git_path() should not use file relocation
  path: convert do_git_path to take a 'struct repository'
  path: convert strbuf_git_common_path to take a 'struct repository'
  path: always pass in commondir to update_common_dir
  path: create path.h
  environment: store worktree in the_repository
  environment: place key repository state in the_repository
  repository: introduce the repository object
  environment: remove namespace_len variable
  setup: add comment indicating a hack
  setup: don't perform lazy initialization of repository state

20 files changed, 972 insertions, 373 deletions

diff --git a/Makefile b/Makefile
index b94cd5633c..9c9c42f8f9 100644
--- a/Makefile
+++ b/Makefile
@@ -840,6 +840,7 @@ LIB_OBJS += refs/ref-cache.o
 LIB_OBJS += ref-filter.o
 LIB_OBJS += remote.o
 LIB_OBJS += replace_object.o
+LIB_OBJS += repository.o
 LIB_OBJS += rerere.o
 LIB_OBJS += resolve-undo.o
 LIB_OBJS += revision.o
diff --git a/builtin/grep.c b/builtin/grep.c
index f752f642ff..fa351c49f4 100644
--- a/builtin/grep.c
+++ b/builtin/grep.c
@@ -4,6 +4,7 @@
  * Copyright (c) 2006 Junio C Hamano
  */
 #include "cache.h"
+#include "repository.h"
 #include "config.h"
 #include "blob.h"
 #include "tree.h"
@@ -643,7 +644,7 @@ static int grep_submodule_launch(struct grep_opt *opt,
 static int grep_submodule(struct grep_opt *opt, const struct object_id *oid,
 			  const char *filename, const char *path)
 {
-	if (!is_submodule_initialized(path))
+	if (!is_submodule_active(the_repository, path))
 		return 0;
 	if (!is_submodule_populated_gently(path, NULL)) {
 		/*
diff --git a/builtin/ls-files.c b/builtin/ls-files.c
index b12d0bb612..b8514a0029 100644
--- a/builtin/ls-files.c
+++ b/builtin/ls-files.c
@@ -5,7 +5,9 @@
  *
  * Copyright (C) Linus Torvalds, 2005
  */
+#define NO_THE_INDEX_COMPATIBILITY_MACROS
 #include "cache.h"
+#include "repository.h"
 #include "config.h"
 #include "quote.h"
 #include "dir.h"
@@ -32,10 +34,8 @@ static int line_terminator = '\n';
 static int debug_mode;
 static int show_eol;
 static int recurse_submodules;
-static struct argv_array submodule_options = ARGV_ARRAY_INIT;
 
 static const char *prefix;
-static const char *super_prefix;
 static int max_prefix_len;
 static int prefix_len;
 static struct pathspec pathspec;
@@ -74,24 +74,11 @@ static void write_eolinfo(const struct index_state *istate,
 static void write_name(const char *name)
 {
 	/*
-	 * Prepend the super_prefix to name to construct the full_name to be
-	 * written.
-	 */
-	struct strbuf full_name = STRBUF_INIT;
-	if (super_prefix) {
-		strbuf_addstr(&full_name, super_prefix);
-		strbuf_addstr(&full_name, name);
-		name = full_name.buf;
-	}
-
-	/*
 	 * With "--full-name", prefix_len=0; this caller needs to pass
 	 * an empty string in that case (a NULL is good for "").
 	 */
 	write_name_quoted_relative(name, prefix_len ? prefix : NULL,
 				   stdout, line_terminator);
-
-	strbuf_release(&full_name);
 }
 
 static const char *get_tag(const struct cache_entry *ce, const char *tag)
@@ -210,83 +197,38 @@ static void show_killed_files(const struct index_state *istate,
 	}
 }
 
-/*
- * Compile an argv_array with all of the options supported by --recurse_submodules
- */
-static void compile_submodule_options(const char **argv,
-				      const struct dir_struct *dir,
-				      int show_tag)
-{
-	if (line_terminator == '\0')
-		argv_array_push(&submodule_options, "-z");
-	if (show_tag)
-		argv_array_push(&submodule_options, "-t");
-	if (show_valid_bit)
-		argv_array_push(&submodule_options, "-v");
-	if (show_cached)
-		argv_array_push(&submodule_options, "--cached");
-	if (show_eol)
-		argv_array_push(&submodule_options, "--eol");
-	if (debug_mode)
-		argv_array_push(&submodule_options, "--debug");
-
-	/* Add Pathspecs */
-	argv_array_push(&submodule_options, "--");
-	for (; *argv; argv++)
-		argv_array_push(&submodule_options, *argv);
-}
+static void show_files(struct repository *repo, struct dir_struct *dir);
 
-/**
- * Recursively call ls-files on a submodule
- */
-static void show_gitlink(const struct cache_entry *ce)
+static void show_submodule(struct repository *superproject,
+			   struct dir_struct *dir, const char *path)
 {
-	struct child_process cp = CHILD_PROCESS_INIT;
-	int status;
-	char *dir;
-
-	prepare_submodule_repo_env(&cp.env_array);
-	argv_array_push(&cp.env_array, GIT_DIR_ENVIRONMENT);
-
-	if (prefix_len)
-		argv_array_pushf(&cp.env_array, "%s=%s",
-				 GIT_TOPLEVEL_PREFIX_ENVIRONMENT,
-				 prefix);
-	argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
-			 super_prefix ? super_prefix : "",
-			 ce->name);
-	argv_array_push(&cp.args, "ls-files");
-	argv_array_push(&cp.args, "--recurse-submodules");
-
-	/* add supported options */
-	argv_array_pushv(&cp.args, submodule_options.argv);
-
-	cp.git_cmd = 1;
-	dir = mkpathdup("%s/%s", get_git_work_tree(), ce->name);
-	cp.dir = dir;
-	status = run_command(&cp);
-	free(dir);
-	if (status)
-		exit(status);
+	struct repository submodule;
+
+	if (repo_submodule_init(&submodule, superproject, path))
+		return;
+
+	if (repo_read_index(&submodule) < 0)
+		die("index file corrupt");
+
+	repo_read_gitmodules(&submodule);
+
+	show_files(&submodule, dir);
+
+	repo_clear(&submodule);
 }
 
-static void show_ce_entry(const struct index_state *istate,
-			  const char *tag, const struct cache_entry *ce)
+static void show_ce(struct repository *repo, struct dir_struct *dir,
+		    const struct cache_entry *ce, const char *fullname,
+		    const char *tag)
 {
-	struct strbuf name = STRBUF_INIT;
-	int len = max_prefix_len;
-	if (super_prefix)
-		strbuf_addstr(&name, super_prefix);
-	strbuf_addstr(&name, ce->name);
-
-	if (len > ce_namelen(ce))
+	if (max_prefix_len > strlen(fullname))
 		die("git ls-files: internal error - cache entry not superset of prefix");
 
 	if (recurse_submodules && S_ISGITLINK(ce->ce_mode) &&
-	    submodule_path_match(&pathspec, name.buf, ps_matched)) {
-		show_gitlink(ce);
-	} else if (match_pathspec(&pathspec, name.buf, name.len,
-				  len, ps_matched,
+	    is_submodule_active(repo, ce->name)) {
+		show_submodule(repo, dir, ce->name);
+	} else if (match_pathspec(&pathspec, fullname, strlen(fullname),
+				  max_prefix_len, ps_matched,
 				  S_ISDIR(ce->ce_mode) ||
 				  S_ISGITLINK(ce->ce_mode))) {
 		tag = get_tag(ce, tag);
@@ -300,12 +242,10 @@ static void show_ce_entry(const struct index_state *istate,
 			       find_unique_abbrev(ce->oid.hash, abbrev),
 			       ce_stage(ce));
 		}
-		write_eolinfo(istate, ce, ce->name);
-		write_name(ce->name);
+		write_eolinfo(repo->index, ce, fullname);
+		write_name(fullname);
 		print_debug(ce);
 	}
-
-	strbuf_release(&name);
 }
 
 static void show_ru_info(const struct index_state *istate)
@@ -338,59 +278,79 @@ static void show_ru_info(const struct index_state *istate)
 }
 
 static int ce_excluded(struct dir_struct *dir, struct index_state *istate,
-		       const struct cache_entry *ce)
+		       const char *fullname, const struct cache_entry *ce)
 {
 	int dtype = ce_to_dtype(ce);
-	return is_excluded(dir, istate, ce->name, &dtype);
+	return is_excluded(dir, istate, fullname, &dtype);
+}
+
+static void construct_fullname(struct strbuf *out, const struct repository *repo,
+			       const struct cache_entry *ce)
+{
+	strbuf_reset(out);
+	if (repo->submodule_prefix)
+		strbuf_addstr(out, repo->submodule_prefix);
+	strbuf_addstr(out, ce->name);
 }
 
-static void show_files(struct index_state *istate, struct dir_struct *dir)
+static void show_files(struct repository *repo, struct dir_struct *dir)
 {
 	int i;
+	struct strbuf fullname = STRBUF_INIT;
 
 	/* For cached/deleted files we don't need to even do the readdir */
 	if (show_others || show_killed) {
 		if (!show_others)
 			dir->flags |= DIR_COLLECT_KILLED_ONLY;
-		fill_directory(dir, istate, &pathspec);
+		fill_directory(dir, repo->index, &pathspec);
 		if (show_others)
-			show_other_files(istate, dir);
+			show_other_files(repo->index, dir);
 		if (show_killed)
-			show_killed_files(istate, dir);
+			show_killed_files(repo->index, dir);
 	}
 	if (show_cached || show_stage) {
-		for (i = 0; i < istate->cache_nr; i++) {
-			const struct cache_entry *ce = istate->cache[i];
+		for (i = 0; i < repo->index->cache_nr; i++) {
+			const struct cache_entry *ce = repo->index->cache[i];
+
+			construct_fullname(&fullname, repo, ce);
+
 			if ((dir->flags & DIR_SHOW_IGNORED) &&
-			    !ce_excluded(dir, istate, ce))
+			    !ce_excluded(dir, repo->index, fullname.buf, ce))
 				continue;
 			if (show_unmerged && !ce_stage(ce))
 				continue;
 			if (ce->ce_flags & CE_UPDATE)
 				continue;
-			show_ce_entry(istate, ce_stage(ce) ? tag_unmerged :
-				(ce_skip_worktree(ce) ? tag_skip_worktree : tag_cached), ce);
+			show_ce(repo, dir, ce, fullname.buf,
+				ce_stage(ce) ? tag_unmerged :
+				(ce_skip_worktree(ce) ? tag_skip_worktree :
+				 tag_cached));
 		}
 	}
 	if (show_deleted || show_modified) {
-		for (i = 0; i < istate->cache_nr; i++) {
-			const struct cache_entry *ce = istate->cache[i];
+		for (i = 0; i < repo->index->cache_nr; i++) {
+			const struct cache_entry *ce = repo->index->cache[i];
 			struct stat st;
 			int err;
+
+			construct_fullname(&fullname, repo, ce);
+
 			if ((dir->flags & DIR_SHOW_IGNORED) &&
-			    !ce_excluded(dir, istate, ce))
+			    !ce_excluded(dir, repo->index, fullname.buf, ce))
 				continue;
 			if (ce->ce_flags & CE_UPDATE)
 				continue;
 			if (ce_skip_worktree(ce))
 				continue;
-			err = lstat(ce->name, &st);
+			err = lstat(fullname.buf, &st);
 			if (show_deleted && err)
-				show_ce_entry(istate, tag_removed, ce);
-			if (show_modified && ie_modified(istate, ce, &st, 0))
-				show_ce_entry(istate, tag_modified, ce);
+				show_ce(repo, dir, ce, fullname.buf, tag_removed);
+			if (show_modified && ie_modified(repo->index, ce, &st, 0))
+				show_ce(repo, dir, ce, fullname.buf, tag_modified);
 		}
 	}
+
+	strbuf_release(&fullname);
 }
 
 /*
@@ -615,10 +575,9 @@ int cmd_ls_files(int argc, const char **argv, const char *cmd_prefix)
 	prefix = cmd_prefix;
 	if (prefix)
 		prefix_len = strlen(prefix);
-	super_prefix = get_super_prefix();
 	git_config(git_default_config, NULL);
 
-	if (read_cache() < 0)
+	if (repo_read_index(the_repository) < 0)
 		die("index file corrupt");
 
 	argc = parse_options(argc, argv, prefix, builtin_ls_files_options,
@@ -652,7 +611,7 @@ int cmd_ls_files(int argc, const char **argv, const char *cmd_prefix)
 		setup_work_tree();
 
 	if (recurse_submodules)
-		compile_submodule_options(argv, &dir, show_tag);
+		repo_read_gitmodules(the_repository);
 
 	if (recurse_submodules &&
 	    (show_stage || show_deleted || show_others || show_unmerged ||
@@ -670,7 +629,10 @@ int cmd_ls_files(int argc, const char **argv, const char *cmd_prefix)
 	/*
 	 * Find common prefix for all pathspec's
 	 * This is used as a performance optimization which unfortunately cannot
-	 * be done when recursing into submodules
+	 * be done when recursing into submodules because when a pathspec is
+	 * given which spans repository boundaries you can't simply remove the
+	 * submodule entry because the pathspec may match something inside the
+	 * submodule.
 	 */
 	if (recurse_submodules)
 		max_prefix = NULL;
@@ -678,7 +640,7 @@ int cmd_ls_files(int argc, const char **argv, const char *cmd_prefix)
 		max_prefix = common_prefix(&pathspec);
 	max_prefix_len = get_common_prefix_len(max_prefix);
 
-	prune_index(&the_index, max_prefix, max_prefix_len);
+	prune_index(the_repository->index, max_prefix, max_prefix_len);
 
 	/* Treat unmatching pathspec elements as errors */
 	if (pathspec.nr && error_unmatch)
@@ -699,11 +661,13 @@ int cmd_ls_files(int argc, const char **argv, const char *cmd_prefix)
 		 */
 		if (show_stage || show_unmerged)
 			die("ls-files --with-tree is incompatible with -s or -u");
-		overlay_tree_on_index(&the_index, with_tree, max_prefix);
+		overlay_tree_on_index(the_repository->index, with_tree, max_prefix);
 	}
-	show_files(&the_index, &dir);
+
+	show_files(the_repository, &dir);
+
 	if (show_resolve_undo)
-		show_ru_info(&the_index);
+		show_ru_info(the_repository->index);
 
 	if (ps_matched) {
 		int bad;
diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 8517032b3e..e1b06c41d8 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -1,4 +1,5 @@
 #include "builtin.h"
+#include "repository.h"
 #include "cache.h"
 #include "config.h"
 #include "parse-options.h"
@@ -280,7 +281,7 @@ static void module_list_active(struct module_list *list)
 	for (i = 0; i < list->nr; i++) {
 		const struct cache_entry *ce = list->entries[i];
 
-		if (!is_submodule_initialized(ce->name))
+		if (!is_submodule_active(the_repository, ce->name))
 			continue;
 
 		ALLOC_GROW(active_modules.entries,
@@ -362,7 +363,7 @@ static void init_submodule(const char *path, const char *prefix, int quiet)
 	 *
 	 * Set active flag for the submodule being initialized
 	 */
-	if (!is_submodule_initialized(path)) {
+	if (!is_submodule_active(the_repository, path)) {
 		strbuf_reset(&sb);
 		strbuf_addf(&sb, "submodule.%s.active", sub->name);
 		git_config_set_gently(sb.buf, "true");
@@ -817,7 +818,7 @@ static int prepare_to_clone_next_submodule(const struct cache_entry *ce,
 	}
 
 	/* Check if the submodule has been initialized. */
-	if (!is_submodule_initialized(ce->name)) {
+	if (!is_submodule_active(the_repository, ce->name)) {
 		next_submodule_warn_missing(suc, out, displaypath);
 		goto cleanup;
 	}
@@ -1193,7 +1194,7 @@ static int is_active(int argc, const char **argv, const char *prefix)
 
 	gitmodules_config();
 
-	return !is_submodule_initialized(argv[1]);
+	return !is_submodule_active(the_repository, argv[1]);
 }
 
 #define SUPPORT_SUPER_PREFIX (1<<0)
diff --git a/cache.h b/cache.h
index 96055c2229..c958fc3ce5 100644
--- a/cache.h
+++ b/cache.h
@@ -11,6 +11,7 @@
 #include "string-list.h"
 #include "pack-revindex.h"
 #include "hash.h"
+#include "path.h"
 
 #ifndef platform_SHA_CTX
 /*
@@ -462,6 +463,8 @@ static inline enum object_type object_type(unsigned int mode)
  */
 extern const char * const local_repo_env[];
 
+extern void setup_git_env(void);
+
 /*
  * Returns true iff we have a configured git repository (either via
  * setup_git_directory, or in the environment via $GIT_DIR).
@@ -769,7 +772,6 @@ extern int core_apply_sparse_checkout;
 extern int precomposed_unicode;
 extern int protect_hfs;
 extern int protect_ntfs;
-extern int git_db_env, git_index_env, git_graft_env, git_common_dir_env;
 
 /*
  * Include broken refs in all ref iterations, which will
@@ -892,64 +894,6 @@ extern void check_repository_format(void);
 #define TYPE_CHANGED    0x0040
 
 /*
- * Return a statically allocated filename, either generically (mkpath), in
- * the repository directory (git_path), or in a submodule's repository
- * directory (git_path_submodule). In all cases, note that the result
- * may be overwritten by another call to _any_ of the functions. Consider
- * using the safer "dup" or "strbuf" formats below (in some cases, the
- * unsafe versions have already been removed).
- */
-extern const char *mkpath(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
-extern const char *git_path(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
-extern const char *git_common_path(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
-
-extern char *mksnpath(char *buf, size_t n, const char *fmt, ...)
-	__attribute__((format (printf, 3, 4)));
-extern void strbuf_git_path(struct strbuf *sb, const char *fmt, ...)
-	__attribute__((format (printf, 2, 3)));
-extern void strbuf_git_common_path(struct strbuf *sb, const char *fmt, ...)
-	__attribute__((format (printf, 2, 3)));
-extern char *git_path_buf(struct strbuf *buf, const char *fmt, ...)
-	__attribute__((format (printf, 2, 3)));
-extern int strbuf_git_path_submodule(struct strbuf *sb, const char *path,
-				     const char *fmt, ...)
-	__attribute__((format (printf, 3, 4)));
-extern char *git_pathdup(const char *fmt, ...)
-	__attribute__((format (printf, 1, 2)));
-extern char *mkpathdup(const char *fmt, ...)
-	__attribute__((format (printf, 1, 2)));
-extern char *git_pathdup_submodule(const char *path, const char *fmt, ...)
-	__attribute__((format (printf, 2, 3)));
-
-extern void report_linked_checkout_garbage(void);
-
-/*
- * You can define a static memoized git path like:
- *
- *    static GIT_PATH_FUNC(git_path_foo, "FOO");
- *
- * or use one of the global ones below.
- */
-#define GIT_PATH_FUNC(func, filename) \
-	const char *func(void) \
-	{ \
-		static char *ret; \
-		if (!ret) \
-			ret = git_pathdup(filename); \
-		return ret; \
-	}
-
-const char *git_path_cherry_pick_head(void);
-const char *git_path_revert_head(void);
-const char *git_path_squash_msg(void);
-const char *git_path_merge_msg(void);
-const char *git_path_merge_rr(void);
-const char *git_path_merge_mode(void);
-const char *git_path_merge_head(void);
-const char *git_path_fetch_head(void);
-const char *git_path_shallow(void);
-
-/*
  * Return the name of the file in the local object database that would
  * be used to store a loose object with the specified sha1.  The
  * return value is a pointer to a statically allocated buffer that is
diff --git a/config.c b/config.c
index 1cd40a5fe6..4638b0696a 100644
--- a/config.c
+++ b/config.c
@@ -7,6 +7,7 @@
  */
 #include "cache.h"
 #include "config.h"
+#include "repository.h"
 #include "lockfile.h"
 #include "exec_cmd.h"
 #include "strbuf.h"
@@ -72,13 +73,6 @@ static int core_compression_seen;
 static int pack_compression_seen;
 static int zlib_compression_seen;
 
-/*
- * Default config_set that contains key-value pairs from the usual set of config
- * config files (i.e repo specific .git/config, user wide ~/.gitconfig, XDG
- * config file and the global /etc/gitconfig)
- */
-static struct config_set the_config_set;
-
 static int config_file_fgetc(struct config_source *conf)
 {
 	return getc_unlocked(conf->u.file);
@@ -1604,31 +1598,6 @@ int config_with_options(config_fn_t fn, void *data,
 	return do_git_config_sequence(opts, fn, data);
 }
 
-static void git_config_raw(config_fn_t fn, void *data)
-{
-	struct config_options opts = {0};
-
-	opts.respect_includes = 1;
-	if (have_git_dir()) {
-		opts.commondir = get_git_common_dir();
-		opts.git_dir = get_git_dir();
-	}
-
-	if (config_with_options(fn, data, NULL, &opts) < 0)
-		/*
-		 * config_with_options() normally returns only
-		 * zero, as most errors are fatal, and
-		 * non-fatal potential errors are guarded by "if"
-		 * statements that are entered only when no error is
-		 * possible.
-		 *
-		 * If we ever encounter a non-fatal error, it means
-		 * something went really wrong and we should stop
-		 * immediately.
-		 */
-		die(_("unknown error occurred while reading the configuration files"));
-}
-
 static void configset_iter(struct config_set *cs, config_fn_t fn, void *data)
 {
 	int i, value_index;
@@ -1682,14 +1651,6 @@ void read_early_config(config_fn_t cb, void *data)
 	strbuf_release(&gitdir);
 }
 
-static void git_config_check_init(void);
-
-void git_config(config_fn_t fn, void *data)
-{
-	git_config_check_init();
-	configset_iter(&the_config_set, fn, data);
-}
-
 static struct config_set_element *configset_find_element(struct config_set *cs, const char *key)
 {
 	struct config_set_element k;
@@ -1899,87 +1860,194 @@ int git_configset_get_pathname(struct config_set *cs, const char *key, const cha
 		return 1;
 }
 
-static void git_config_check_init(void)
+/* Functions use to read configuration from a repository */
+static void repo_read_config(struct repository *repo)
 {
-	if (the_config_set.hash_initialized)
+	struct config_options opts;
+
+	opts.respect_includes = 1;
+	opts.commondir = repo->commondir;
+	opts.git_dir = repo->gitdir;
+
+	if (!repo->config)
+		repo->config = xcalloc(1, sizeof(struct config_set));
+	else
+		git_configset_clear(repo->config);
+
+	git_configset_init(repo->config);
+
+	if (config_with_options(config_set_callback, repo->config, NULL, &opts) < 0)
+		/*
+		 * config_with_options() normally returns only
+		 * zero, as most errors are fatal, and
+		 * non-fatal potential errors are guarded by "if"
+		 * statements that are entered only when no error is
+		 * possible.
+		 *
+		 * If we ever encounter a non-fatal error, it means
+		 * something went really wrong and we should stop
+		 * immediately.
+		 */
+		die(_("unknown error occurred while reading the configuration files"));
+}
+
+static void git_config_check_init(struct repository *repo)
+{
+	if (repo->config && repo->config->hash_initialized)
 		return;
-	git_configset_init(&the_config_set);
-	git_config_raw(config_set_callback, &the_config_set);
+	repo_read_config(repo);
 }
 
-void git_config_clear(void)
+static void repo_config_clear(struct repository *repo)
 {
-	if (!the_config_set.hash_initialized)
+	if (!repo->config || !repo->config->hash_initialized)
 		return;
-	git_configset_clear(&the_config_set);
+	git_configset_clear(repo->config);
 }
 
-int git_config_get_value(const char *key, const char **value)
+void repo_config(struct repository *repo, config_fn_t fn, void *data)
 {
-	git_config_check_init();
-	return git_configset_get_value(&the_config_set, key, value);
+	git_config_check_init(repo);
+	configset_iter(repo->config, fn, data);
 }
 
-const struct string_list *git_config_get_value_multi(const char *key)
+int repo_config_get_value(struct repository *repo,
+			  const char *key, const char **value)
 {
-	git_config_check_init();
-	return git_configset_get_value_multi(&the_config_set, key);
+	git_config_check_init(repo);
+	return git_configset_get_value(repo->config, key, value);
 }
 
-int git_config_get_string_const(const char *key, const char **dest)
+const struct string_list *repo_config_get_value_multi(struct repository *repo,
+						      const char *key)
+{
+	git_config_check_init(repo);
+	return git_configset_get_value_multi(repo->config, key);
+}
+
+int repo_config_get_string_const(struct repository *repo,
+				 const char *key, const char **dest)
+{
+	int ret;
+	git_config_check_init(repo);
+	ret = git_configset_get_string_const(repo->config, key, dest);
+	if (ret < 0)
+		git_die_config(key, NULL);
+	return ret;
+}
+
+int repo_config_get_string(struct repository *repo,
+			   const char *key, char **dest)
+{
+	git_config_check_init(repo);
+	return repo_config_get_string_const(repo, key, (const char **)dest);
+}
+
+int repo_config_get_int(struct repository *repo,
+			const char *key, int *dest)
+{
+	git_config_check_init(repo);
+	return git_configset_get_int(repo->config, key, dest);
+}
+
+int repo_config_get_ulong(struct repository *repo,
+			  const char *key, unsigned long *dest)
+{
+	git_config_check_init(repo);
+	return git_configset_get_ulong(repo->config, key, dest);
+}
+
+int repo_config_get_bool(struct repository *repo,
+			 const char *key, int *dest)
+{
+	git_config_check_init(repo);
+	return git_configset_get_bool(repo->config, key, dest);
+}
+
+int repo_config_get_bool_or_int(struct repository *repo,
+				const char *key, int *is_bool, int *dest)
+{
+	git_config_check_init(repo);
+	return git_configset_get_bool_or_int(repo->config, key, is_bool, dest);
+}
+
+int repo_config_get_maybe_bool(struct repository *repo,
+			       const char *key, int *dest)
+{
+	git_config_check_init(repo);
+	return git_configset_get_maybe_bool(repo->config, key, dest);
+}
+
+int repo_config_get_pathname(struct repository *repo,
+			     const char *key, const char **dest)
 {
 	int ret;
-	git_config_check_init();
-	ret = git_configset_get_string_const(&the_config_set, key, dest);
+	git_config_check_init(repo);
+	ret = git_configset_get_pathname(repo->config, key, dest);
 	if (ret < 0)
 		git_die_config(key, NULL);
 	return ret;
 }
 
+/* Functions used historically to read configuration from 'the_repository' */
+void git_config(config_fn_t fn, void *data)
+{
+	repo_config(the_repository, fn, data);
+}
+
+void git_config_clear(void)
+{
+	repo_config_clear(the_repository);
+}
+
+int git_config_get_value(const char *key, const char **value)
+{
+	return repo_config_get_value(the_repository, key, value);
+}
+
+const struct string_list *git_config_get_value_multi(const char *key)
+{
+	return repo_config_get_value_multi(the_repository, key);
+}
+
+int git_config_get_string_const(const char *key, const char **dest)
+{
+	return repo_config_get_string_const(the_repository, key, dest);
+}
+
 int git_config_get_string(const char *key, char **dest)
 {
-	git_config_check_init();
-	return git_config_get_string_const(key, (const char **)dest);
+	return repo_config_get_string(the_repository, key, dest);
 }
 
 int git_config_get_int(const char *key, int *dest)
 {
-	git_config_check_init();
-	return git_configset_get_int(&the_config_set, key, dest);
+	return repo_config_get_int(the_repository, key, dest);
 }
 
 int git_config_get_ulong(const char *key, unsigned long *dest)
 {
-	git_config_check_init();
-	return git_configset_get_ulong(&the_config_set, key, dest);
+	return repo_config_get_ulong(the_repository, key, dest);
 }
 
 int git_config_get_bool(const char *key, int *dest)
 {
-	git_config_check_init();
-	return git_configset_get_bool(&the_config_set, key, dest);
+	return repo_config_get_bool(the_repository, key, dest);
 }
 
 int git_config_get_bool_or_int(const char *key, int *is_bool, int *dest)
 {
-	git_config_check_init();
-	return git_configset_get_bool_or_int(&the_config_set, key, is_bool, dest);
+	return repo_config_get_bool_or_int(the_repository, key, is_bool, dest);
 }
 
 int git_config_get_maybe_bool(const char *key, int *dest)
 {
-	git_config_check_init();
-	return git_configset_get_maybe_bool(&the_config_set, key, dest);
+	return repo_config_get_maybe_bool(the_repository, key, dest);
 }
 
 int git_config_get_pathname(const char *key, const char **dest)
 {
-	int ret;
-	git_config_check_init();
-	ret = git_configset_get_pathname(&the_config_set, key, dest);
-	if (ret < 0)
-		git_die_config(key, NULL);
-	return ret;
+	return repo_config_get_pathname(the_repository, key, dest);
 }
 
 int git_config_get_expiry(const char *key, const char **output)
diff --git a/config.h b/config.h
index 9e038cce25..0352da117b 100644
--- a/config.h
+++ b/config.h
@@ -163,6 +163,30 @@ extern int git_configset_get_bool_or_int(struct config_set *cs, const char *key,
 extern int git_configset_get_maybe_bool(struct config_set *cs, const char *key, int *dest);
 extern int git_configset_get_pathname(struct config_set *cs, const char *key, const char **dest);
 
+/* Functions for reading a repository's config */
+struct repository;
+extern void repo_config(struct repository *repo, config_fn_t fn, void *data);
+extern int repo_config_get_value(struct repository *repo,
+				 const char *key, const char **value);
+extern const struct string_list *repo_config_get_value_multi(struct repository *repo,
+							     const char *key);
+extern int repo_config_get_string_const(struct repository *repo,
+					const char *key, const char **dest);
+extern int repo_config_get_string(struct repository *repo,
+				  const char *key, char **dest);
+extern int repo_config_get_int(struct repository *repo,
+			       const char *key, int *dest);
+extern int repo_config_get_ulong(struct repository *repo,
+				 const char *key, unsigned long *dest);
+extern int repo_config_get_bool(struct repository *repo,
+				const char *key, int *dest);
+extern int repo_config_get_bool_or_int(struct repository *repo,
+				       const char *key, int *is_bool, int *dest);
+extern int repo_config_get_maybe_bool(struct repository *repo,
+				      const char *key, int *dest);
+extern int repo_config_get_pathname(struct repository *repo,
+				    const char *key, const char **dest);
+
 extern int git_config_get_value(const char *key, const char **value);
 extern const struct string_list *git_config_get_value_multi(const char *key);
 extern void git_config_clear(void);
diff --git a/environment.c b/environment.c
index d40b21fb72..3fd4b10845 100644
--- a/environment.c
+++ b/environment.c
@@ -8,6 +8,7 @@
  * are.
  */
 #include "cache.h"
+#include "repository.h"
 #include "config.h"
 #include "refs.h"
 #include "fmt-merge-msg.h"
@@ -95,17 +96,11 @@ int ignore_untracked_cache_config;
 
 /* This is set by setup_git_dir_gently() and/or git_default_config() */
 char *git_work_tree_cfg;
-static char *work_tree;
 
 static const char *namespace;
-static size_t namespace_len;
 
 static const char *super_prefix;
 
-static const char *git_dir, *git_common_dir;
-static char *git_object_dir, *git_index_file, *git_graft_file;
-int git_db_env, git_index_env, git_graft_env, git_common_dir_env;
-
 /*
  * Repository-local GIT_* environment variables; see cache.h for details.
  */
@@ -149,48 +144,17 @@ static char *expand_namespace(const char *raw_namespace)
 	return strbuf_detach(&buf, NULL);
 }
 
-static char *git_path_from_env(const char *envvar, const char *git_dir,
-			       const char *path, int *fromenv)
+void setup_git_env(void)
 {
-	const char *value = getenv(envvar);
-	if (!value)
-		return xstrfmt("%s/%s", git_dir, path);
-	if (fromenv)
-		*fromenv = 1;
-	return xstrdup(value);
-}
-
-static void setup_git_env(void)
-{
-	struct strbuf sb = STRBUF_INIT;
-	const char *gitfile;
 	const char *shallow_file;
 	const char *replace_ref_base;
 
-	git_dir = getenv(GIT_DIR_ENVIRONMENT);
-	if (!git_dir) {
-		if (!startup_info->have_repository)
-			BUG("setup_git_env called without repository");
-		git_dir = DEFAULT_GIT_DIR_ENVIRONMENT;
-	}
-	gitfile = read_gitfile(git_dir);
-	git_dir = xstrdup(gitfile ? gitfile : git_dir);
-	if (get_common_dir(&sb, git_dir))
-		git_common_dir_env = 1;
-	git_common_dir = strbuf_detach(&sb, NULL);
-	git_object_dir = git_path_from_env(DB_ENVIRONMENT, git_common_dir,
-					   "objects", &git_db_env);
-	git_index_file = git_path_from_env(INDEX_ENVIRONMENT, git_dir,
-					   "index", &git_index_env);
-	git_graft_file = git_path_from_env(GRAFT_ENVIRONMENT, git_common_dir,
-					   "info/grafts", &git_graft_env);
 	if (getenv(NO_REPLACE_OBJECTS_ENVIRONMENT))
 		check_replace_refs = 0;
 	replace_ref_base = getenv(GIT_REPLACE_REF_BASE_ENVIRONMENT);
 	git_replace_ref_base = xstrdup(replace_ref_base ? replace_ref_base
 							  : "refs/replace/");
 	namespace = expand_namespace(getenv(GIT_NAMESPACE_ENVIRONMENT));
-	namespace_len = strlen(namespace);
 	shallow_file = getenv(GIT_SHALLOW_FILE_ENVIRONMENT);
 	if (shallow_file)
 		set_alternate_shallow_file(shallow_file, 0);
@@ -205,36 +169,36 @@ int is_bare_repository(void)
 int have_git_dir(void)
 {
 	return startup_info->have_repository
-		|| git_dir
-		|| getenv(GIT_DIR_ENVIRONMENT);
+		|| the_repository->gitdir;
 }
 
 const char *get_git_dir(void)
 {
-	if (!git_dir)
-		setup_git_env();
-	return git_dir;
+	if (!the_repository->gitdir)
+		BUG("git environment hasn't been setup");
+	return the_repository->gitdir;
 }
 
 const char *get_git_common_dir(void)
 {
-	if (!git_dir)
-		setup_git_env();
-	return git_common_dir;
+	if (!the_repository->commondir)
+		BUG("git environment hasn't been setup");
+	return the_repository->commondir;
 }
 
 const char *get_git_namespace(void)
 {
 	if (!namespace)
-		setup_git_env();
+		BUG("git environment hasn't been setup");
 	return namespace;
 }
 
 const char *strip_namespace(const char *namespaced_ref)
 {
-	if (!starts_with(namespaced_ref, get_git_namespace()))
-		return NULL;
-	return namespaced_ref + namespace_len;
+	const char *out;
+	if (skip_prefix(namespaced_ref, get_git_namespace(), &out))
+		return out;
+	return NULL;
 }
 
 const char *get_super_prefix(void)
@@ -258,26 +222,26 @@ void set_git_work_tree(const char *new_work_tree)
 {
 	if (git_work_tree_initialized) {
 		new_work_tree = real_path(new_work_tree);
-		if (strcmp(new_work_tree, work_tree))
+		if (strcmp(new_work_tree, the_repository->worktree))
 			die("internal error: work tree has already been set\n"
 			    "Current worktree: %s\nNew worktree: %s",
-			    work_tree, new_work_tree);
+			    the_repository->worktree, new_work_tree);
 		return;
 	}
 	git_work_tree_initialized = 1;
-	work_tree = real_pathdup(new_work_tree, 1);
+	repo_set_worktree(the_repository, new_work_tree);
 }
 
 const char *get_git_work_tree(void)
 {
-	return work_tree;
+	return the_repository->worktree;
 }
 
 char *get_object_directory(void)
 {
-	if (!git_object_dir)
-		setup_git_env();
-	return git_object_dir;
+	if (!the_repository->objectdir)
+		BUG("git environment hasn't been setup");
+	return the_repository->objectdir;
 }
 
 int odb_mkstemp(struct strbuf *template, const char *pattern)
@@ -315,22 +279,23 @@ int odb_pack_keep(const char *name)
 
 char *get_index_file(void)
 {
-	if (!git_index_file)
-		setup_git_env();
-	return git_index_file;
+	if (!the_repository->index_file)
+		BUG("git environment hasn't been setup");
+	return the_repository->index_file;
 }
 
 char *get_graft_file(void)
 {
-	if (!git_graft_file)
-		setup_git_env();
-	return git_graft_file;
+	if (!the_repository->graft_file)
+		BUG("git environment hasn't been setup");
+	return the_repository->graft_file;
 }
 
 int set_git_dir(const char *path)
 {
 	if (setenv(GIT_DIR_ENVIRONMENT, path, 1))
 		return error("Could not set GIT_DIR to '%s'", path);
+	repo_set_gitdir(the_repository, path);
 	setup_git_env();
 	return 0;
 }
diff --git a/git.c b/git.c
index 5be27b07e5..489aab4d83 100644
--- a/git.c
+++ b/git.c
@@ -400,7 +400,7 @@ static struct cmd_struct commands[] = {
 	{ "init-db", cmd_init_db },
 	{ "interpret-trailers", cmd_interpret_trailers, RUN_SETUP_GENTLY },
 	{ "log", cmd_log, RUN_SETUP },
-	{ "ls-files", cmd_ls_files, RUN_SETUP | SUPPORT_SUPER_PREFIX },
+	{ "ls-files", cmd_ls_files, RUN_SETUP },
 	{ "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
 	{ "ls-tree", cmd_ls_tree, RUN_SETUP },
 	{ "mailinfo", cmd_mailinfo, RUN_SETUP_GENTLY },
diff --git a/path.c b/path.c
index c1cb1cf627..e485f9f931 100644
--- a/path.c
+++ b/path.c
@@ -2,11 +2,13 @@
  * Utilities for paths and pathnames
  */
 #include "cache.h"
+#include "repository.h"
 #include "strbuf.h"
 #include "string-list.h"
 #include "dir.h"
 #include "worktree.h"
 #include "submodule-config.h"
+#include "path.h"
 
 static int get_st_mode_bits(const char *path, int *mode)
 {
@@ -343,8 +345,6 @@ static void update_common_dir(struct strbuf *buf, int git_dir_len,
 {
 	char *base = buf->buf + git_dir_len;
 	init_common_trie();
-	if (!common_dir)
-		common_dir = get_git_common_dir();
 	if (trie_find(&common_trie, base, check_common, NULL) > 0)
 		replace_dir(buf, git_dir_len, common_dir);
 }
@@ -355,7 +355,7 @@ void report_linked_checkout_garbage(void)
 	const struct common_dir *p;
 	int len;
 
-	if (!git_common_dir_env)
+	if (!the_repository->different_commondir)
 		return;
 	strbuf_addf(&sb, "%s/", get_git_dir());
 	len = sb.len;
@@ -371,42 +371,78 @@ void report_linked_checkout_garbage(void)
 	strbuf_release(&sb);
 }
 
-static void adjust_git_path(struct strbuf *buf, int git_dir_len)
+static void adjust_git_path(const struct repository *repo,
+			    struct strbuf *buf, int git_dir_len)
 {
 	const char *base = buf->buf + git_dir_len;
-	if (git_graft_env && is_dir_file(base, "info", "grafts"))
+	if (is_dir_file(base, "info", "grafts"))
 		strbuf_splice(buf, 0, buf->len,
-			      get_graft_file(), strlen(get_graft_file()));
-	else if (git_index_env && !strcmp(base, "index"))
+			      repo->graft_file, strlen(repo->graft_file));
+	else if (!strcmp(base, "index"))
 		strbuf_splice(buf, 0, buf->len,
-			      get_index_file(), strlen(get_index_file()));
-	else if (git_db_env && dir_prefix(base, "objects"))
-		replace_dir(buf, git_dir_len + 7, get_object_directory());
+			      repo->index_file, strlen(repo->index_file));
+	else if (dir_prefix(base, "objects"))
+		replace_dir(buf, git_dir_len + 7, repo->objectdir);
 	else if (git_hooks_path && dir_prefix(base, "hooks"))
 		replace_dir(buf, git_dir_len + 5, git_hooks_path);
-	else if (git_common_dir_env)
-		update_common_dir(buf, git_dir_len, NULL);
+	else if (repo->different_commondir)
+		update_common_dir(buf, git_dir_len, repo->commondir);
 }
 
-static void do_git_path(const struct worktree *wt, struct strbuf *buf,
+static void strbuf_worktree_gitdir(struct strbuf *buf,
+				   const struct repository *repo,
+				   const struct worktree *wt)
+{
+	if (!wt)
+		strbuf_addstr(buf, repo->gitdir);
+	else if (!wt->id)
+		strbuf_addstr(buf, repo->commondir);
+	else
+		strbuf_git_common_path(buf, repo, "worktrees/%s", wt->id);
+}
+
+static void do_git_path(const struct repository *repo,
+			const struct worktree *wt, struct strbuf *buf,
 			const char *fmt, va_list args)
 {
 	int gitdir_len;
-	strbuf_addstr(buf, get_worktree_git_dir(wt));
+	strbuf_worktree_gitdir(buf, repo, wt);
 	if (buf->len && !is_dir_sep(buf->buf[buf->len - 1]))
 		strbuf_addch(buf, '/');
 	gitdir_len = buf->len;
 	strbuf_vaddf(buf, fmt, args);
-	adjust_git_path(buf, gitdir_len);
+	if (!wt)
+		adjust_git_path(repo, buf, gitdir_len);
 	strbuf_cleanup_path(buf);
 }
 
+char *repo_git_path(const struct repository *repo,
+		    const char *fmt, ...)
+{
+	struct strbuf path = STRBUF_INIT;
+	va_list args;
+	va_start(args, fmt);
+	do_git_path(repo, NULL, &path, fmt, args);
+	va_end(args);
+	return strbuf_detach(&path, NULL);
+}
+
+void strbuf_repo_git_path(struct strbuf *sb,
+			  const struct repository *repo,
+			  const char *fmt, ...)
+{
+	va_list args;
+	va_start(args, fmt);
+	do_git_path(repo, NULL, sb, fmt, args);
+	va_end(args);
+}
+
 char *git_path_buf(struct strbuf *buf, const char *fmt, ...)
 {
 	va_list args;
 	strbuf_reset(buf);
 	va_start(args, fmt);
-	do_git_path(NULL, buf, fmt, args);
+	do_git_path(the_repository, NULL, buf, fmt, args);
 	va_end(args);
 	return buf->buf;
 }
@@ -415,7 +451,7 @@ void strbuf_git_path(struct strbuf *sb, const char *fmt, ...)
 {
 	va_list args;
 	va_start(args, fmt);
-	do_git_path(NULL, sb, fmt, args);
+	do_git_path(the_repository, NULL, sb, fmt, args);
 	va_end(args);
 }
 
@@ -424,7 +460,7 @@ const char *git_path(const char *fmt, ...)
 	struct strbuf *pathname = get_pathname();
 	va_list args;
 	va_start(args, fmt);
-	do_git_path(NULL, pathname, fmt, args);
+	do_git_path(the_repository, NULL, pathname, fmt, args);
 	va_end(args);
 	return pathname->buf;
 }
@@ -434,7 +470,7 @@ char *git_pathdup(const char *fmt, ...)
 	struct strbuf path = STRBUF_INIT;
 	va_list args;
 	va_start(args, fmt);
-	do_git_path(NULL, &path, fmt, args);
+	do_git_path(the_repository, NULL, &path, fmt, args);
 	va_end(args);
 	return strbuf_detach(&path, NULL);
 }
@@ -465,11 +501,52 @@ const char *worktree_git_path(const struct worktree *wt, const char *fmt, ...)
 	struct strbuf *pathname = get_pathname();
 	va_list args;
 	va_start(args, fmt);
-	do_git_path(wt, pathname, fmt, args);
+	do_git_path(the_repository, wt, pathname, fmt, args);
 	va_end(args);
 	return pathname->buf;
 }
 
+static void do_worktree_path(const struct repository *repo,
+			     struct strbuf *buf,
+			     const char *fmt, va_list args)
+{
+	strbuf_addstr(buf, repo->worktree);
+	if(buf->len && !is_dir_sep(buf->buf[buf->len - 1]))
+		strbuf_addch(buf, '/');
+
+	strbuf_vaddf(buf, fmt, args);
+	strbuf_cleanup_path(buf);
+}
+
+char *repo_worktree_path(const struct repository *repo, const char *fmt, ...)
+{
+	struct strbuf path = STRBUF_INIT;
+	va_list args;
+
+	if (!repo->worktree)
+		return NULL;
+
+	va_start(args, fmt);
+	do_worktree_path(repo, &path, fmt, args);
+	va_end(args);
+
+	return strbuf_detach(&path, NULL);
+}
+
+void strbuf_repo_worktree_path(struct strbuf *sb,
+			       const struct repository *repo,
+			       const char *fmt, ...)
+{
+	va_list args;
+
+	if (!repo->worktree)
+		return;
+
+	va_start(args, fmt);
+	do_worktree_path(repo, sb, fmt, args);
+	va_end(args);
+}
+
 /* Returns 0 on success, negative on failure. */
 static int do_submodule_path(struct strbuf *buf, const char *path,
 			     const char *fmt, va_list args)
@@ -524,11 +601,12 @@ int strbuf_git_path_submodule(struct strbuf *buf, const char *path,
 	return err;
 }
 
-static void do_git_common_path(struct strbuf *buf,
+static void do_git_common_path(const struct repository *repo,
+			       struct strbuf *buf,
 			       const char *fmt,
 			       va_list args)
 {
-	strbuf_addstr(buf, get_git_common_dir());
+	strbuf_addstr(buf, repo->commondir);
 	if (buf->len && !is_dir_sep(buf->buf[buf->len - 1]))
 		strbuf_addch(buf, '/');
 	strbuf_vaddf(buf, fmt, args);
@@ -540,16 +618,18 @@ const char *git_common_path(const char *fmt, ...)
 	struct strbuf *pathname = get_pathname();
 	va_list args;
 	va_start(args, fmt);
-	do_git_common_path(pathname, fmt, args);
+	do_git_common_path(the_repository, pathname, fmt, args);
 	va_end(args);
 	return pathname->buf;
 }
 
-void strbuf_git_common_path(struct strbuf *sb, const char *fmt, ...)
+void strbuf_git_common_path(struct strbuf *sb,
+			    const struct repository *repo,
+			    const char *fmt, ...)
 {
 	va_list args;
 	va_start(args, fmt);
-	do_git_common_path(sb, fmt, args);
+	do_git_common_path(repo, sb, fmt, args);
 	va_end(args);
 }
 
diff --git a/path.h b/path.h
new file mode 100644
index 0000000000..9541620c79
--- /dev/null
+++ b/path.h
@@ -0,0 +1,82 @@
+#ifndef PATH_H
+#define PATH_H
+
+struct repository;
+
+/*
+ * Return a statically allocated filename, either generically (mkpath), in
+ * the repository directory (git_path), or in a submodule's repository
+ * directory (git_path_submodule). In all cases, note that the result
+ * may be overwritten by another call to _any_ of the functions. Consider
+ * using the safer "dup" or "strbuf" formats below (in some cases, the
+ * unsafe versions have already been removed).
+ */
+extern const char *mkpath(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
+extern const char *git_path(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
+extern const char *git_common_path(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
+
+extern char *mksnpath(char *buf, size_t n, const char *fmt, ...)
+	__attribute__((format (printf, 3, 4)));
+extern void strbuf_git_path(struct strbuf *sb, const char *fmt, ...)
+	__attribute__((format (printf, 2, 3)));
+extern void strbuf_git_common_path(struct strbuf *sb,
+				   const struct repository *repo,
+				   const char *fmt, ...)
+	__attribute__((format (printf, 3, 4)));
+extern char *git_path_buf(struct strbuf *buf, const char *fmt, ...)
+	__attribute__((format (printf, 2, 3)));
+extern int strbuf_git_path_submodule(struct strbuf *sb, const char *path,
+				     const char *fmt, ...)
+	__attribute__((format (printf, 3, 4)));
+extern char *git_pathdup(const char *fmt, ...)
+	__attribute__((format (printf, 1, 2)));
+extern char *mkpathdup(const char *fmt, ...)
+	__attribute__((format (printf, 1, 2)));
+extern char *git_pathdup_submodule(const char *path, const char *fmt, ...)
+	__attribute__((format (printf, 2, 3)));
+
+extern char *repo_git_path(const struct repository *repo,
+			   const char *fmt, ...)
+	__attribute__((format (printf, 2, 3)));
+extern void strbuf_repo_git_path(struct strbuf *sb,
+				 const struct repository *repo,
+				 const char *fmt, ...)
+	__attribute__((format (printf, 3, 4)));
+
+extern char *repo_worktree_path(const struct repository *repo,
+				const char *fmt, ...)
+	__attribute__((format (printf, 2, 3)));
+extern void strbuf_repo_worktree_path(struct strbuf *sb,
+				      const struct repository *repo,
+				      const char *fmt, ...)
+	__attribute__((format (printf, 3, 4)));
+
+extern void report_linked_checkout_garbage(void);
+
+/*
+ * You can define a static memoized git path like:
+ *
+ *    static GIT_PATH_FUNC(git_path_foo, "FOO");
+ *
+ * or use one of the global ones below.
+ */
+#define GIT_PATH_FUNC(func, filename) \
+	const char *func(void) \
+	{ \
+		static char *ret; \
+		if (!ret) \
+			ret = git_pathdup(filename); \
+		return ret; \
+	}
+
+const char *git_path_cherry_pick_head(void);
+const char *git_path_revert_head(void);
+const char *git_path_squash_msg(void);
+const char *git_path_merge_msg(void);
+const char *git_path_merge_rr(void);
+const char *git_path_merge_mode(void);
+const char *git_path_merge_head(void);
+const char *git_path_fetch_head(void);
+const char *git_path_shallow(void);
+
+#endif /* PATH_H */
diff --git a/repository.c b/repository.c
new file mode 100644
index 0000000000..edca907404
--- /dev/null
+++ b/repository.c
@@ -0,0 +1,242 @@
+#include "cache.h"
+#include "repository.h"
+#include "config.h"
+#include "submodule-config.h"
+
+/* The main repository */
+static struct repository the_repo;
+struct repository *the_repository = &the_repo;
+
+static char *git_path_from_env(const char *envvar, const char *git_dir,
+			       const char *path, int fromenv)
+{
+	if (fromenv) {
+		const char *value = getenv(envvar);
+		if (value)
+			return xstrdup(value);
+	}
+
+	return xstrfmt("%s/%s", git_dir, path);
+}
+
+static int find_common_dir(struct strbuf *sb, const char *gitdir, int fromenv)
+{
+	if (fromenv) {
+		const char *value = getenv(GIT_COMMON_DIR_ENVIRONMENT);
+		if (value) {
+			strbuf_addstr(sb, value);
+			return 1;
+		}
+	}
+
+	return get_common_dir_noenv(sb, gitdir);
+}
+
+static void repo_setup_env(struct repository *repo)
+{
+	struct strbuf sb = STRBUF_INIT;
+
+	repo->different_commondir = find_common_dir(&sb, repo->gitdir,
+						    !repo->ignore_env);
+	repo->commondir = strbuf_detach(&sb, NULL);
+	repo->objectdir = git_path_from_env(DB_ENVIRONMENT, repo->commondir,
+					    "objects", !repo->ignore_env);
+	repo->graft_file = git_path_from_env(GRAFT_ENVIRONMENT, repo->commondir,
+					     "info/grafts", !repo->ignore_env);
+	repo->index_file = git_path_from_env(INDEX_ENVIRONMENT, repo->gitdir,
+					     "index", !repo->ignore_env);
+}
+
+void repo_set_gitdir(struct repository *repo, const char *path)
+{
+	const char *gitfile = read_gitfile(path);
+
+	/*
+	 * NEEDSWORK: Eventually we want to be able to free gitdir and the rest
+	 * of the environment before reinitializing it again, but we have some
+	 * crazy code paths where we try to set gitdir with the current gitdir
+	 * and we don't want to free gitdir before copying the passed in value.
+	 */
+	repo->gitdir = xstrdup(gitfile ? gitfile : path);
+
+	repo_setup_env(repo);
+}
+
+/*
+ * Attempt to resolve and set the provided 'gitdir' for repository 'repo'.
+ * Return 0 upon success and a non-zero value upon failure.
+ */
+static int repo_init_gitdir(struct repository *repo, const char *gitdir)
+{
+	int ret = 0;
+	int error = 0;
+	char *abspath = NULL;
+	const char *resolved_gitdir;
+
+	abspath = real_pathdup(gitdir, 0);
+	if (!abspath) {
+		ret = -1;
+		goto out;
+	}
+
+	/* 'gitdir' must reference the gitdir directly */
+	resolved_gitdir = resolve_gitdir_gently(abspath, &error);
+	if (!resolved_gitdir) {
+		ret = -1;
+		goto out;
+	}
+
+	repo_set_gitdir(repo, resolved_gitdir);
+
+out:
+	free(abspath);
+	return ret;
+}
+
+void repo_set_worktree(struct repository *repo, const char *path)
+{
+	repo->worktree = real_pathdup(path, 1);
+}
+
+static int read_and_verify_repository_format(struct repository_format *format,
+					     const char *commondir)
+{
+	int ret = 0;
+	struct strbuf sb = STRBUF_INIT;
+
+	strbuf_addf(&sb, "%s/config", commondir);
+	read_repository_format(format, sb.buf);
+	strbuf_reset(&sb);
+
+	if (verify_repository_format(format, &sb) < 0) {
+		warning("%s", sb.buf);
+		ret = -1;
+	}
+
+	strbuf_release(&sb);
+	return ret;
+}
+
+/*
+ * Initialize 'repo' based on the provided 'gitdir'.
+ * Return 0 upon success and a non-zero value upon failure.
+ */
+int repo_init(struct repository *repo, const char *gitdir, const char *worktree)
+{
+	struct repository_format format;
+	memset(repo, 0, sizeof(*repo));
+
+	repo->ignore_env = 1;
+
+	if (repo_init_gitdir(repo, gitdir))
+		goto error;
+
+	if (read_and_verify_repository_format(&format, repo->commondir))
+		goto error;
+
+	if (worktree)
+		repo_set_worktree(repo, worktree);
+
+	return 0;
+
+error:
+	repo_clear(repo);
+	return -1;
+}
+
+/*
+ * Initialize 'submodule' as the submodule given by 'path' in parent repository
+ * 'superproject'.
+ * Return 0 upon success and a non-zero value upon failure.
+ */
+int repo_submodule_init(struct repository *submodule,
+			struct repository *superproject,
+			const char *path)
+{
+	const struct submodule *sub;
+	struct strbuf gitdir = STRBUF_INIT;
+	struct strbuf worktree = STRBUF_INIT;
+	int ret = 0;
+
+	sub = submodule_from_cache(superproject, null_sha1, path);
+	if (!sub) {
+		ret = -1;
+		goto out;
+	}
+
+	strbuf_repo_worktree_path(&gitdir, superproject, "%s/.git", path);
+	strbuf_repo_worktree_path(&worktree, superproject, "%s", path);
+
+	if (repo_init(submodule, gitdir.buf, worktree.buf)) {
+		/*
+		 * If initilization fails then it may be due to the submodule
+		 * not being populated in the superproject's worktree.  Instead
+		 * we can try to initilize the submodule by finding it's gitdir
+		 * in the superproject's 'modules' directory.  In this case the
+		 * submodule would not have a worktree.
+		 */
+		strbuf_reset(&gitdir);
+		strbuf_repo_git_path(&gitdir, superproject,
+				     "modules/%s", sub->name);
+
+		if (repo_init(submodule, gitdir.buf, NULL)) {
+			ret = -1;
+			goto out;
+		}
+	}
+
+	submodule->submodule_prefix = xstrfmt("%s%s/",
+					      superproject->submodule_prefix ?
+					      superproject->submodule_prefix :
+					      "", path);
+
+out:
+	strbuf_release(&gitdir);
+	strbuf_release(&worktree);
+	return ret;
+}
+
+void repo_clear(struct repository *repo)
+{
+	free(repo->gitdir);
+	repo->gitdir = NULL;
+	free(repo->commondir);
+	repo->commondir = NULL;
+	free(repo->objectdir);
+	repo->objectdir = NULL;
+	free(repo->graft_file);
+	repo->graft_file = NULL;
+	free(repo->index_file);
+	repo->index_file = NULL;
+	free(repo->worktree);
+	repo->worktree = NULL;
+	free(repo->submodule_prefix);
+	repo->submodule_prefix = NULL;
+
+	if (repo->config) {
+		git_configset_clear(repo->config);
+		free(repo->config);
+		repo->config = NULL;
+	}
+
+	if (repo->submodule_cache) {
+		submodule_cache_free(repo->submodule_cache);
+		repo->submodule_cache = NULL;
+	}
+
+	if (repo->index) {
+		discard_index(repo->index);
+		free(repo->index);
+		repo->index = NULL;
+	}
+}
+
+int repo_read_index(struct repository *repo)
+{
+	if (!repo->index)
+		repo->index = xcalloc(1, sizeof(*repo->index));
+	else
+		discard_index(repo->index);
+
+	return read_index_from(repo->index, repo->index_file);
+}
diff --git a/repository.h b/repository.h
new file mode 100644
index 0000000000..417787f3ef
--- /dev/null
+++ b/repository.h
@@ -0,0 +1,97 @@
+#ifndef REPOSITORY_H
+#define REPOSITORY_H
+
+struct config_set;
+struct index_state;
+struct submodule_cache;
+
+struct repository {
+	/* Environment */
+	/*
+	 * Path to the git directory.
+	 * Cannot be NULL after initialization.
+	 */
+	char *gitdir;
+
+	/*
+	 * Path to the common git directory.
+	 * Cannot be NULL after initialization.
+	 */
+	char *commondir;
+
+	/*
+	 * Path to the repository's object store.
+	 * Cannot be NULL after initialization.
+	 */
+	char *objectdir;
+
+	/*
+	 * Path to the repository's graft file.
+	 * Cannot be NULL after initialization.
+	 */
+	char *graft_file;
+
+	/*
+	 * Path to the current worktree's index file.
+	 * Cannot be NULL after initialization.
+	 */
+	char *index_file;
+
+	/*
+	 * Path to the working directory.
+	 * A NULL value indicates that there is no working directory.
+	 */
+	char *worktree;
+
+	/*
+	 * Path from the root of the top-level superproject down to this
+	 * repository.  This is only non-NULL if the repository is initialized
+	 * as a submodule of another repository.
+	 */
+	char *submodule_prefix;
+
+	/* Subsystems */
+	/*
+	 * Repository's config which contains key-value pairs from the usual
+	 * set of config files (i.e. repo specific .git/config, user wide
+	 * ~/.gitconfig, XDG config file and the global /etc/gitconfig)
+	 */
+	struct config_set *config;
+
+	/* Repository's submodule config as defined by '.gitmodules' */
+	struct submodule_cache *submodule_cache;
+
+	/*
+	 * Repository's in-memory index.
+	 * 'repo_read_index()' can be used to populate 'index'.
+	 */
+	struct index_state *index;
+
+	/* Configurations */
+	/*
+	 * Bit used during initialization to indicate if repository state (like
+	 * the location of the 'objectdir') should be read from the
+	 * environment.  By default this bit will be set at the begining of
+	 * 'repo_init()' so that all repositories will ignore the environment.
+	 * The exception to this is 'the_repository', which doesn't go through
+	 * the normal 'repo_init()' process.
+	 */
+	unsigned ignore_env:1;
+
+	/* Indicate if a repository has a different 'commondir' from 'gitdir' */
+	unsigned different_commondir:1;
+};
+
+extern struct repository *the_repository;
+
+extern void repo_set_gitdir(struct repository *repo, const char *path);
+extern void repo_set_worktree(struct repository *repo, const char *path);
+extern int repo_init(struct repository *repo, const char *gitdir, const char *worktree);
+extern int repo_submodule_init(struct repository *submodule,
+			       struct repository *superproject,
+			       const char *path);
+extern void repo_clear(struct repository *repo);
+
+extern int repo_read_index(struct repository *repo);
+
+#endif /* REPOSITORY_H */
diff --git a/setup.c b/setup.c
index 358fbc2e53..860507e1fd 100644
--- a/setup.c
+++ b/setup.c
@@ -1,4 +1,5 @@
 #include "cache.h"
+#include "repository.h"
 #include "config.h"
 #include "dir.h"
 #include "string-list.h"
@@ -398,6 +399,11 @@ void setup_work_tree(void)
 	if (getenv(GIT_WORK_TREE_ENVIRONMENT))
 		setenv(GIT_WORK_TREE_ENVIRONMENT, ".", 1);
 
+	/*
+	 * NEEDSWORK: this call can essentially be set_git_dir(get_git_dir())
+	 * which can cause some problems when trying to free the old value of
+	 * gitdir.
+	 */
 	set_git_dir(remove_leading_path(git_dir, work_tree));
 	initialized = 1;
 }
@@ -1079,6 +1085,12 @@ const char *setup_git_directory_gently(int *nongit_ok)
 		die("BUG: unhandled setup_git_directory_1() result");
 	}
 
+	/*
+	 * NEEDSWORK: This was a hack in order to get ls-files and grep to have
+	 * properly formated output when recursing submodules.  Once ls-files
+	 * and grep have been changed to perform this recursing in-process this
+	 * needs to be removed.
+	 */
 	env_prefix = getenv(GIT_TOPLEVEL_PREFIX_ENVIRONMENT);
 	if (env_prefix)
 		prefix = env_prefix;
@@ -1091,6 +1103,27 @@ const char *setup_git_directory_gently(int *nongit_ok)
 	startup_info->have_repository = !nongit_ok || !*nongit_ok;
 	startup_info->prefix = prefix;
 
+	/*
+	 * Not all paths through the setup code will call 'set_git_dir()' (which
+	 * directly sets up the environment) so in order to guarantee that the
+	 * environment is in a consistent state after setup, explicitly setup
+	 * the environment if we have a repository.
+	 *
+	 * NEEDSWORK: currently we allow bogus GIT_DIR values to be set in some
+	 * code paths so we also need to explicitly setup the environment if
+	 * the user has set GIT_DIR.  It may be beneficial to disallow bogus
+	 * GIT_DIR values at some point in the future.
+	 */
+	if (startup_info->have_repository || getenv(GIT_DIR_ENVIRONMENT)) {
+		if (!the_repository->gitdir) {
+			const char *gitdir = getenv(GIT_DIR_ENVIRONMENT);
+			if (!gitdir)
+				gitdir = DEFAULT_GIT_DIR_ENVIRONMENT;
+			repo_set_gitdir(the_repository, gitdir);
+			setup_git_env();
+		}
+	}
+
 	strbuf_release(&dir);
 	strbuf_release(&gitdir);
 
diff --git a/submodule-config.c b/submodule-config.c
index d8f8d5ea32..37cfcceb95 100644
--- a/submodule-config.c
+++ b/submodule-config.c
@@ -1,4 +1,5 @@
 #include "cache.h"
+#include "repository.h"
 #include "config.h"
 #include "submodule-config.h"
 #include "submodule.h"
@@ -15,6 +16,7 @@
 struct submodule_cache {
 	struct hashmap for_path;
 	struct hashmap for_name;
+	unsigned initialized:1;
 };
 
 /*
@@ -31,9 +33,6 @@ enum lookup_type {
 	lookup_path
 };
 
-static struct submodule_cache the_submodule_cache;
-static int is_cache_init;
-
 static int config_path_cmp(const struct submodule_entry *a,
 			   const struct submodule_entry *b,
 			   const void *unused)
@@ -50,10 +49,16 @@ static int config_name_cmp(const struct submodule_entry *a,
 	       hashcmp(a->config->gitmodules_sha1, b->config->gitmodules_sha1);
 }
 
-static void cache_init(struct submodule_cache *cache)
+static struct submodule_cache *submodule_cache_alloc(void)
+{
+	return xcalloc(1, sizeof(struct submodule_cache));
+}
+
+static void submodule_cache_init(struct submodule_cache *cache)
 {
 	hashmap_init(&cache->for_path, (hashmap_cmp_fn) config_path_cmp, 0);
 	hashmap_init(&cache->for_name, (hashmap_cmp_fn) config_name_cmp, 0);
+	cache->initialized = 1;
 }
 
 static void free_one_config(struct submodule_entry *entry)
@@ -65,11 +70,14 @@ static void free_one_config(struct submodule_entry *entry)
 	free(entry->config);
 }
 
-static void cache_free(struct submodule_cache *cache)
+static void submodule_cache_clear(struct submodule_cache *cache)
 {
 	struct hashmap_iter iter;
 	struct submodule_entry *entry;
 
+	if (!cache->initialized)
+		return;
+
 	/*
 	 * We iterate over the name hash here to be symmetric with the
 	 * allocation of struct submodule entries. Each is allocated by
@@ -81,6 +89,13 @@ static void cache_free(struct submodule_cache *cache)
 
 	hashmap_free(&cache->for_path, 1);
 	hashmap_free(&cache->for_name, 1);
+	cache->initialized = 0;
+}
+
+void submodule_cache_free(struct submodule_cache *cache)
+{
+	submodule_cache_clear(cache);
+	free(cache);
 }
 
 static unsigned int hash_sha1_string(const unsigned char *sha1,
@@ -494,43 +509,62 @@ out:
 	return submodule;
 }
 
-static void ensure_cache_init(void)
+static void submodule_cache_check_init(struct repository *repo)
 {
-	if (is_cache_init)
+	if (repo->submodule_cache && repo->submodule_cache->initialized)
 		return;
 
-	cache_init(&the_submodule_cache);
-	is_cache_init = 1;
+	if (!repo->submodule_cache)
+		repo->submodule_cache = submodule_cache_alloc();
+
+	submodule_cache_init(repo->submodule_cache);
 }
 
-int parse_submodule_config_option(const char *var, const char *value)
+int submodule_config_option(struct repository *repo,
+			    const char *var, const char *value)
 {
 	struct parse_config_parameter parameter;
-	parameter.cache = &the_submodule_cache;
+
+	submodule_cache_check_init(repo);
+
+	parameter.cache = repo->submodule_cache;
 	parameter.treeish_name = NULL;
 	parameter.gitmodules_sha1 = null_sha1;
 	parameter.overwrite = 1;
 
-	ensure_cache_init();
 	return parse_config(var, value, &parameter);
 }
 
+int parse_submodule_config_option(const char *var, const char *value)
+{
+	return submodule_config_option(the_repository, var, value);
+}
+
 const struct submodule *submodule_from_name(const unsigned char *treeish_name,
 		const char *name)
 {
-	ensure_cache_init();
-	return config_from(&the_submodule_cache, treeish_name, name, lookup_name);
+	submodule_cache_check_init(the_repository);
+	return config_from(the_repository->submodule_cache, treeish_name, name, lookup_name);
 }
 
 const struct submodule *submodule_from_path(const unsigned char *treeish_name,
 		const char *path)
 {
-	ensure_cache_init();
-	return config_from(&the_submodule_cache, treeish_name, path, lookup_path);
+	submodule_cache_check_init(the_repository);
+	return config_from(the_repository->submodule_cache, treeish_name, path, lookup_path);
+}
+
+const struct submodule *submodule_from_cache(struct repository *repo,
+					     const unsigned char *treeish_name,
+					     const char *key)
+{
+	submodule_cache_check_init(repo);
+	return config_from(repo->submodule_cache, treeish_name,
+			   key, lookup_path);
 }
 
 void submodule_free(void)
 {
-	cache_free(&the_submodule_cache);
-	is_cache_init = 0;
+	if (the_repository->submodule_cache)
+		submodule_cache_clear(the_repository->submodule_cache);
 }
diff --git a/submodule-config.h b/submodule-config.h
index d434ecdb45..bc45a25e85 100644
--- a/submodule-config.h
+++ b/submodule-config.h
@@ -22,14 +22,24 @@ struct submodule {
 	int recommend_shallow;
 };
 
+struct submodule_cache;
+struct repository;
+
+extern void submodule_cache_free(struct submodule_cache *cache);
+
 extern int parse_fetch_recurse_submodules_arg(const char *opt, const char *arg);
 extern int parse_update_recurse_submodules_arg(const char *opt, const char *arg);
 extern int parse_push_recurse_submodules_arg(const char *opt, const char *arg);
 extern int parse_submodule_config_option(const char *var, const char *value);
+extern int submodule_config_option(struct repository *repo,
+				   const char *var, const char *value);
 extern const struct submodule *submodule_from_name(
 		const unsigned char *commit_or_tree, const char *name);
 extern const struct submodule *submodule_from_path(
 		const unsigned char *commit_or_tree, const char *path);
+extern const struct submodule *submodule_from_cache(struct repository *repo,
+						    const unsigned char *treeish_name,
+						    const char *key);
 extern int gitmodule_sha1_from_commit(const unsigned char *commit_sha1,
 				      unsigned char *gitmodules_sha1,
 				      struct strbuf *rev);
diff --git a/submodule.c b/submodule.c
index 71e0c5a85b..da2b484879 100644
--- a/submodule.c
+++ b/submodule.c
@@ -1,4 +1,5 @@
 #include "cache.h"
+#include "repository.h"
 #include "config.h"
 #include "submodule-config.h"
 #include "submodule.h"
@@ -255,6 +256,20 @@ void gitmodules_config(void)
 	}
 }
 
+static int gitmodules_cb(const char *var, const char *value, void *data)
+{
+	struct repository *repo = data;
+	return submodule_config_option(repo, var, value);
+}
+
+void repo_read_gitmodules(struct repository *repo)
+{
+	char *gitmodules_path = repo_worktree_path(repo, ".gitmodules");
+
+	git_config_from_file(gitmodules_cb, gitmodules_path, repo);
+	free(gitmodules_path);
+}
+
 void gitmodules_config_sha1(const unsigned char *commit_sha1)
 {
 	struct strbuf rev = STRBUF_INIT;
@@ -268,21 +283,17 @@ void gitmodules_config_sha1(const unsigned char *commit_sha1)
 }
 
 /*
- * NEEDSWORK: With the addition of different configuration options to determine
- * if a submodule is of interests, the validity of this function's name comes
- * into question.  Once the dust has settled and more concrete terminology is
- * decided upon, come up with a more proper name for this function.  One
- * potential candidate could be 'is_submodule_active()'.
- *
  * Determine if a submodule has been initialized at a given 'path'
  */
-int is_submodule_initialized(const char *path)
+int is_submodule_active(struct repository *repo, const char *path)
 {
 	int ret = 0;
 	char *key = NULL;
 	char *value = NULL;
 	const struct string_list *sl;
-	const struct submodule *module = submodule_from_path(null_sha1, path);
+	const struct submodule *module;
+
+	module = submodule_from_cache(repo, null_sha1, path);
 
 	/* early return if there isn't a path->module mapping */
 	if (!module)
@@ -290,14 +301,14 @@ int is_submodule_initialized(const char *path)
 
 	/* submodule.<name>.active is set */
 	key = xstrfmt("submodule.%s.active", module->name);
-	if (!git_config_get_bool(key, &ret)) {
+	if (!repo_config_get_bool(repo, key, &ret)) {
 		free(key);
 		return ret;
 	}
 	free(key);
 
 	/* submodule.active is set */
-	sl = git_config_get_value_multi("submodule.active");
+	sl = repo_config_get_value_multi(repo, "submodule.active");
 	if (sl) {
 		struct pathspec ps;
 		struct argv_array args = ARGV_ARRAY_INIT;
@@ -317,7 +328,7 @@ int is_submodule_initialized(const char *path)
 
 	/* fallback to checking if the URL is set */
 	key = xstrfmt("submodule.%s.url", module->name);
-	ret = !git_config_get_string(key, &value);
+	ret = !repo_config_get_string(repo, key, &value);
 
 	free(value);
 	free(key);
@@ -1517,7 +1528,7 @@ int submodule_move_head(const char *path,
 	const struct submodule *sub;
 	int *error_code_ptr, error_code;
 
-	if (!is_submodule_initialized(path))
+	if (!is_submodule_active(the_repository, path))
 		return 0;
 
 	if (flags & SUBMODULE_MOVE_HEAD_FORCE)
diff --git a/submodule.h b/submodule.h
index cbe5c1726f..623ce6ad77 100644
--- a/submodule.h
+++ b/submodule.h
@@ -1,6 +1,7 @@
 #ifndef SUBMODULE_H
 #define SUBMODULE_H
 
+struct repository;
 struct diff_options;
 struct argv_array;
 struct oid_array;
@@ -46,8 +47,9 @@ int option_parse_recurse_submodules_worktree_updater(const struct option *opt,
 						     const char *arg, int unset);
 void load_submodule_cache(void);
 extern void gitmodules_config(void);
+extern void repo_read_gitmodules(struct repository *repo);
 extern void gitmodules_config_sha1(const unsigned char *commit_sha1);
-extern int is_submodule_initialized(const char *path);
+extern int is_submodule_active(struct repository *repo, const char *path);
 /*
  * Determine if a submodule has been populated at a given 'path' by checking if
  * the <path>/.git resolves to a valid git repository.
diff --git a/t/t3007-ls-files-recurse-submodules.sh b/t/t3007-ls-files-recurse-submodules.sh
index ebb956fd16..318b5bce7e 100755
--- a/t/t3007-ls-files-recurse-submodules.sh
+++ b/t/t3007-ls-files-recurse-submodules.sh
@@ -135,6 +135,45 @@ test_expect_success '--recurse-submodules and pathspecs setup' '
 	test_cmp expect actual
 '
 
+test_expect_success 'inactive submodule' '
+	test_when_finished "git config --bool submodule.submodule.active true" &&
+	test_when_finished "git -C submodule config --bool submodule.subsub.active true" &&
+	git config --bool submodule.submodule.active "false" &&
+
+	cat >expect <<-\EOF &&
+	.gitmodules
+	a
+	b/b
+	h.txt
+	sib/file
+	sub/file
+	submodule
+	EOF
+
+	git ls-files --recurse-submodules >actual &&
+	test_cmp expect actual &&
+
+	git config --bool submodule.submodule.active "true" &&
+	git -C submodule config --bool submodule.subsub.active "false" &&
+
+	cat >expect <<-\EOF &&
+	.gitmodules
+	a
+	b/b
+	h.txt
+	sib/file
+	sub/file
+	submodule/.gitmodules
+	submodule/c
+	submodule/f.TXT
+	submodule/g.txt
+	submodule/subsub
+	EOF
+
+	git ls-files --recurse-submodules >actual &&
+	test_cmp expect actual
+'
+
 test_expect_success '--recurse-submodules and pathspecs' '
 	cat >expect <<-\EOF &&
 	h.txt
diff --git a/worktree.c b/worktree.c
index 2801c6d52b..e28ffbeb09 100644
--- a/worktree.c
+++ b/worktree.c
@@ -1,4 +1,5 @@
 #include "cache.h"
+#include "repository.h"
 #include "refs.h"
 #include "strbuf.h"
 #include "worktree.h"
@@ -76,7 +77,7 @@ static struct worktree *get_linked_worktree(const char *id)
 	if (!id)
 		die("Missing linked worktree name");
 
-	strbuf_git_common_path(&path, "worktrees/%s/gitdir", id);
+	strbuf_git_common_path(&path, the_repository, "worktrees/%s/gitdir", id);
 	if (strbuf_read_file(&worktree_path, path.buf, 0) <= 0)
 		/* invalid gitdir file */
 		goto done;