submodule-config.c - pub/scm/git/git - Git at Google

 #include "cache.h"
 #include "submodule-config.h"
 #include "submodule.h"
 #include "strbuf.h"

 /*
  * submodule cache lookup structure
  * There is one shared set of 'struct submodule' entries which can be
  * looked up by their sha1 blob id of the .gitmodule file and either
  * using path or name as key.
  * for_path stores submodule entries with path as key
  * for_name stores submodule entries with name as key
  */
 struct submodule_cache {
 	struct hashmap for_path;
 	struct hashmap for_name;
 };

 /*
  * thin wrapper struct needed to insert 'struct submodule' entries to
  * the hashmap
  */
 struct submodule_entry {
 	struct hashmap_entry ent;
 	struct submodule *config;
 };

 enum lookup_type {
 	lookup_name,
 	lookup_path
 };

 static struct submodule_cache cache;
 static int is_cache_init;

 static int config_path_cmp(const struct submodule_entry *a,
 			   const struct submodule_entry *b,
 			   const void *unused)
 {
 	return strcmp(a->config->path, b->config->path) ||
 	       hashcmp(a->config->gitmodules_sha1, b->config->gitmodules_sha1);
 }

 static int config_name_cmp(const struct submodule_entry *a,
 			   const struct submodule_entry *b,
 			   const void *unused)
 {
 	return strcmp(a->config->name, b->config->name) ||
 	       hashcmp(a->config->gitmodules_sha1, b->config->gitmodules_sha1);
 }

 static void 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);
 }

 static void free_one_config(struct submodule_entry *entry)
 {
 	free((void *) entry->config->path);
 	free((void *) entry->config->name);
 	free(entry->config);
 }

 static void cache_free(struct submodule_cache *cache)
 {
 	struct hashmap_iter iter;
 	struct submodule_entry *entry;

 	/*
 	 * We iterate over the name hash here to be symmetric with the
 	 * allocation of struct submodule entries. Each is allocated by
 	 * their .gitmodule blob sha1 and submodule name.
 	 */
 	hashmap_iter_init(&cache->for_name, &iter);
 	while ((entry = hashmap_iter_next(&iter)))
 		free_one_config(entry);

 	hashmap_free(&cache->for_path, 1);
 	hashmap_free(&cache->for_name, 1);
 }

 static unsigned int hash_sha1_string(const unsigned char *sha1,
 				     const char *string)
 {
 	return memhash(sha1, 20) + strhash(string);
 }

 static void cache_put_path(struct submodule_cache *cache,
 			   struct submodule *submodule)
 {
 	unsigned int hash = hash_sha1_string(submodule->gitmodules_sha1,
 					     submodule->path);
 	struct submodule_entry *e = xmalloc(sizeof(*e));
 	hashmap_entry_init(e, hash);
 	e->config = submodule;
 	hashmap_put(&cache->for_path, e);
 }

 static void cache_remove_path(struct submodule_cache *cache,
 			      struct submodule *submodule)
 {
 	unsigned int hash = hash_sha1_string(submodule->gitmodules_sha1,
 					     submodule->path);
 	struct submodule_entry e;
 	struct submodule_entry *removed;
 	hashmap_entry_init(&e, hash);
 	e.config = submodule;
 	removed = hashmap_remove(&cache->for_path, &e, NULL);
 	free(removed);
 }

 static void cache_add(struct submodule_cache *cache,
 		      struct submodule *submodule)
 {
 	unsigned int hash = hash_sha1_string(submodule->gitmodules_sha1,
 					     submodule->name);
 	struct submodule_entry *e = xmalloc(sizeof(*e));
 	hashmap_entry_init(e, hash);
 	e->config = submodule;
 	hashmap_add(&cache->for_name, e);
 }

 static const struct submodule *cache_lookup_path(struct submodule_cache *cache,
 		const unsigned char *gitmodules_sha1, const char *path)
 {
 	struct submodule_entry *entry;
 	unsigned int hash = hash_sha1_string(gitmodules_sha1, path);
 	struct submodule_entry key;
 	struct submodule key_config;

 	hashcpy(key_config.gitmodules_sha1, gitmodules_sha1);
 	key_config.path = path;

 	hashmap_entry_init(&key, hash);
 	key.config = &key_config;

 	entry = hashmap_get(&cache->for_path, &key, NULL);
 	if (entry)
 		return entry->config;
 	return NULL;
 }

 static struct submodule *cache_lookup_name(struct submodule_cache *cache,
 		const unsigned char *gitmodules_sha1, const char *name)
 {
 	struct submodule_entry *entry;
 	unsigned int hash = hash_sha1_string(gitmodules_sha1, name);
 	struct submodule_entry key;
 	struct submodule key_config;

 	hashcpy(key_config.gitmodules_sha1, gitmodules_sha1);
 	key_config.name = name;

 	hashmap_entry_init(&key, hash);
 	key.config = &key_config;

 	entry = hashmap_get(&cache->for_name, &key, NULL);
 	if (entry)
 		return entry->config;
 	return NULL;
 }

 static int name_and_item_from_var(const char *var, struct strbuf *name,
 				  struct strbuf *item)
 {
 	const char *subsection, *key;
 	int subsection_len, parse;
 	parse = parse_config_key(var, "submodule", &subsection,
 			&subsection_len, &key);
 	if (parse < 0 || !subsection)
 		return 0;

 	strbuf_add(name, subsection, subsection_len);
 	strbuf_addstr(item, key);

 	return 1;
 }

 static struct submodule *lookup_or_create_by_name(struct submodule_cache *cache,
 		const unsigned char *gitmodules_sha1, const char *name)
 {
 	struct submodule *submodule;
 	struct strbuf name_buf = STRBUF_INIT;

 	submodule = cache_lookup_name(cache, gitmodules_sha1, name);
 	if (submodule)
 		return submodule;

 	submodule = xmalloc(sizeof(*submodule));

 	strbuf_addstr(&name_buf, name);
 	submodule->name = strbuf_detach(&name_buf, NULL);

 	submodule->path = NULL;
 	submodule->url = NULL;
 	submodule->fetch_recurse = RECURSE_SUBMODULES_NONE;
 	submodule->ignore = NULL;

 	hashcpy(submodule->gitmodules_sha1, gitmodules_sha1);

 	cache_add(cache, submodule);

 	return submodule;
 }

 static int parse_fetch_recurse(const char *opt, const char *arg,
 			       int die_on_error)
 {
 	switch (git_config_maybe_bool(opt, arg)) {
 	case 1:
 		return RECURSE_SUBMODULES_ON;
 	case 0:
 		return RECURSE_SUBMODULES_OFF;
 	default:
 		if (!strcmp(arg, "on-demand"))
 			return RECURSE_SUBMODULES_ON_DEMAND;

 		if (die_on_error)
 			die("bad %s argument: %s", opt, arg);
 		else
 			return RECURSE_SUBMODULES_ERROR;
 	}
 }

 int parse_fetch_recurse_submodules_arg(const char *opt, const char *arg)
 {
 	return parse_fetch_recurse(opt, arg, 1);
 }

 static void warn_multiple_config(const unsigned char *commit_sha1,
 				 const char *name, const char *option)
 {
 	const char *commit_string = "WORKTREE";
 	if (commit_sha1)
 		commit_string = sha1_to_hex(commit_sha1);
 	warning("%s:.gitmodules, multiple configurations found for "
 			"'submodule.%s.%s'. Skipping second one!",
 			commit_string, name, option);
 }

 struct parse_config_parameter {
 	struct submodule_cache *cache;
 	const unsigned char *commit_sha1;
 	const unsigned char *gitmodules_sha1;
 	int overwrite;
 };

 static int parse_config(const char *var, const char *value, void *data)
 {
 	struct parse_config_parameter *me = data;
 	struct submodule *submodule;
 	struct strbuf name = STRBUF_INIT, item = STRBUF_INIT;
 	int ret = 0;

 	/* this also ensures that we only parse submodule entries */
 	if (!name_and_item_from_var(var, &name, &item))
 		return 0;

 	submodule = lookup_or_create_by_name(me->cache, me->gitmodules_sha1,
 			name.buf);

 	if (!strcmp(item.buf, "path")) {
 		struct strbuf path = STRBUF_INIT;
 		if (!value) {
 			ret = config_error_nonbool(var);
 			goto release_return;
 		}
 		if (!me->overwrite && submodule->path != NULL) {
 			warn_multiple_config(me->commit_sha1, submodule->name,
 					"path");
 			goto release_return;
 		}

 		if (submodule->path)
 			cache_remove_path(me->cache, submodule);
 		free((void *) submodule->path);
 		strbuf_addstr(&path, value);
 		submodule->path = strbuf_detach(&path, NULL);
 		cache_put_path(me->cache, submodule);
 	} else if (!strcmp(item.buf, "fetchrecursesubmodules")) {
 		/* when parsing worktree configurations we can die early */
 		int die_on_error = is_null_sha1(me->gitmodules_sha1);
 		if (!me->overwrite &&
 		    submodule->fetch_recurse != RECURSE_SUBMODULES_NONE) {
 			warn_multiple_config(me->commit_sha1, submodule->name,
 					"fetchrecursesubmodules");
 			goto release_return;
 		}

 		submodule->fetch_recurse = parse_fetch_recurse(var, value,
 								die_on_error);
 	} else if (!strcmp(item.buf, "ignore")) {
 		struct strbuf ignore = STRBUF_INIT;
 		if (!me->overwrite && submodule->ignore != NULL) {
 			warn_multiple_config(me->commit_sha1, submodule->name,
 					"ignore");
 			goto release_return;
 		}
 		if (!value) {
 			ret = config_error_nonbool(var);
 			goto release_return;
 		}
 		if (strcmp(value, "untracked") && strcmp(value, "dirty") &&
 		    strcmp(value, "all") && strcmp(value, "none")) {
 			warning("Invalid parameter '%s' for config option "
 					"'submodule.%s.ignore'", value, var);
 			goto release_return;
 		}

 		free((void *) submodule->ignore);
 		strbuf_addstr(&ignore, value);
 		submodule->ignore = strbuf_detach(&ignore, NULL);
 	} else if (!strcmp(item.buf, "url")) {
 		struct strbuf url = STRBUF_INIT;
 		if (!value) {
 			ret = config_error_nonbool(var);
 			goto release_return;
 		}
 		if (!me->overwrite && submodule->url != NULL) {
 			warn_multiple_config(me->commit_sha1, submodule->name,
 					"url");
 			goto release_return;
 		}

 		free((void *) submodule->url);
 		strbuf_addstr(&url, value);
 		submodule->url = strbuf_detach(&url, NULL);
 	}

 release_return:
 	strbuf_release(&name);
 	strbuf_release(&item);

 	return ret;
 }

 static int gitmodule_sha1_from_commit(const unsigned char *commit_sha1,
 				      unsigned char *gitmodules_sha1)
 {
 	struct strbuf rev = STRBUF_INIT;
 	int ret = 0;

 	if (is_null_sha1(commit_sha1)) {
 		hashcpy(gitmodules_sha1, null_sha1);
 		return 1;
 	}

 	strbuf_addf(&rev, "%s:.gitmodules", sha1_to_hex(commit_sha1));
 	if (get_sha1(rev.buf, gitmodules_sha1) >= 0)
 		ret = 1;

 	strbuf_release(&rev);
 	return ret;
 }

 /* This does a lookup of a submodule configuration by name or by path
  * (key) with on-demand reading of the appropriate .gitmodules from
  * revisions.
  */
 static const struct submodule *config_from(struct submodule_cache *cache,
 		const unsigned char *commit_sha1, const char *key,
 		enum lookup_type lookup_type)
 {
 	struct strbuf rev = STRBUF_INIT;
 	unsigned long config_size;
 	char *config;
 	unsigned char sha1[20];
 	enum object_type type;
 	const struct submodule *submodule = NULL;
 	struct parse_config_parameter parameter;

 	/*
 	 * If any parameter except the cache is a NULL pointer just
 	 * return the first submodule. Can be used to check whether
 	 * there are any submodules parsed.
 	 */
 	if (!commit_sha1 || !key) {
 		struct hashmap_iter iter;
 		struct submodule_entry *entry;

 		hashmap_iter_init(&cache->for_name, &iter);
 		entry = hashmap_iter_next(&iter);
 		if (!entry)
 			return NULL;
 		return entry->config;
 	}

 	if (!gitmodule_sha1_from_commit(commit_sha1, sha1))
 		return NULL;

 	switch (lookup_type) {
 	case lookup_name:
 		submodule = cache_lookup_name(cache, sha1, key);
 		break;
 	case lookup_path:
 		submodule = cache_lookup_path(cache, sha1, key);
 		break;
 	}
 	if (submodule)
 		return submodule;

 	config = read_sha1_file(sha1, &type, &config_size);
 	if (!config)
 		return NULL;

 	if (type != OBJ_BLOB) {
 		free(config);
 		return NULL;
 	}

 	/* fill the submodule config into the cache */
 	parameter.cache = cache;
 	parameter.commit_sha1 = commit_sha1;
 	parameter.gitmodules_sha1 = sha1;
 	parameter.overwrite = 0;
 	git_config_from_buf(parse_config, rev.buf, config, config_size,
 			&parameter);
 	free(config);

 	switch (lookup_type) {
 	case lookup_name:
 		return cache_lookup_name(cache, sha1, key);
 	case lookup_path:
 		return cache_lookup_path(cache, sha1, key);
 	default:
 		return NULL;
 	}
 }

 static const struct submodule *config_from_path(struct submodule_cache *cache,
 		const unsigned char *commit_sha1, const char *path)
 {
 	return config_from(cache, commit_sha1, path, lookup_path);
 }

 static const struct submodule *config_from_name(struct submodule_cache *cache,
 		const unsigned char *commit_sha1, const char *name)
 {
 	return config_from(cache, commit_sha1, name, lookup_name);
 }

 static void ensure_cache_init(void)
 {
 	if (is_cache_init)
 		return;

 	cache_init(&cache);
 	is_cache_init = 1;
 }

 int parse_submodule_config_option(const char *var, const char *value)
 {
 	struct parse_config_parameter parameter;
 	parameter.cache = &cache;
 	parameter.commit_sha1 = NULL;
 	parameter.gitmodules_sha1 = null_sha1;
 	parameter.overwrite = 1;

 	ensure_cache_init();
 	return parse_config(var, value, &parameter);
 }

 const struct submodule *submodule_from_name(const unsigned char *commit_sha1,
 		const char *name)
 {
 	ensure_cache_init();
 	return config_from_name(&cache, commit_sha1, name);
 }

 const struct submodule *submodule_from_path(const unsigned char *commit_sha1,
 		const char *path)
 {
 	ensure_cache_init();
 	return config_from_path(&cache, commit_sha1, path);
 }

 void submodule_free(void)
 {
 	cache_free(&cache);
 	is_cache_init = 0;
 }
	#include "cache.h"
	#include "submodule-config.h"
	#include "submodule.h"
	#include "strbuf.h"

	/*
	* submodule cache lookup structure
	* There is one shared set of 'struct submodule' entries which can be
	* looked up by their sha1 blob id of the .gitmodule file and either
	* using path or name as key.
	* for_path stores submodule entries with path as key
	* for_name stores submodule entries with name as key
	*/
	struct submodule_cache {
	struct hashmap for_path;
	struct hashmap for_name;
	};

	/*
	* thin wrapper struct needed to insert 'struct submodule' entries to
	* the hashmap
	*/
	struct submodule_entry {
	struct hashmap_entry ent;
	struct submodule *config;
	};

	enum lookup_type {
	lookup_name,
	lookup_path
	};

	static struct submodule_cache cache;
	static int is_cache_init;

	static int config_path_cmp(const struct submodule_entry *a,
	const struct submodule_entry *b,
	const void *unused)
	{
	return strcmp(a->config->path, b->config->path) \|\|
	hashcmp(a->config->gitmodules_sha1, b->config->gitmodules_sha1);
	}

	static int config_name_cmp(const struct submodule_entry *a,
	const struct submodule_entry *b,
	const void *unused)
	{
	return strcmp(a->config->name, b->config->name) \|\|
	hashcmp(a->config->gitmodules_sha1, b->config->gitmodules_sha1);
	}

	static void 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);
	}

	static void free_one_config(struct submodule_entry *entry)
	{
	free((void *) entry->config->path);
	free((void *) entry->config->name);
	free(entry->config);
	}

	static void cache_free(struct submodule_cache *cache)
	{
	struct hashmap_iter iter;
	struct submodule_entry *entry;

	/*
	* We iterate over the name hash here to be symmetric with the
	* allocation of struct submodule entries. Each is allocated by
	* their .gitmodule blob sha1 and submodule name.
	*/
	hashmap_iter_init(&cache->for_name, &iter);
	while ((entry = hashmap_iter_next(&iter)))
	free_one_config(entry);

	hashmap_free(&cache->for_path, 1);
	hashmap_free(&cache->for_name, 1);
	}

	static unsigned int hash_sha1_string(const unsigned char *sha1,
	const char *string)
	{
	return memhash(sha1, 20) + strhash(string);
	}

	static void cache_put_path(struct submodule_cache *cache,
	struct submodule *submodule)
	{
	unsigned int hash = hash_sha1_string(submodule->gitmodules_sha1,
	submodule->path);
	struct submodule_entry e = xmalloc(sizeof(e));
	hashmap_entry_init(e, hash);
	e->config = submodule;
	hashmap_put(&cache->for_path, e);
	}

	static void cache_remove_path(struct submodule_cache *cache,
	struct submodule *submodule)
	{
	unsigned int hash = hash_sha1_string(submodule->gitmodules_sha1,
	submodule->path);
	struct submodule_entry e;
	struct submodule_entry *removed;
	hashmap_entry_init(&e, hash);
	e.config = submodule;
	removed = hashmap_remove(&cache->for_path, &e, NULL);
	free(removed);
	}

	static void cache_add(struct submodule_cache *cache,
	struct submodule *submodule)
	{
	unsigned int hash = hash_sha1_string(submodule->gitmodules_sha1,
	submodule->name);
	struct submodule_entry e = xmalloc(sizeof(e));
	hashmap_entry_init(e, hash);
	e->config = submodule;
	hashmap_add(&cache->for_name, e);
	}

	static const struct submodule cache_lookup_path(struct submodule_cache cache,
	const unsigned char gitmodules_sha1, const char path)
	{
	struct submodule_entry *entry;
	unsigned int hash = hash_sha1_string(gitmodules_sha1, path);
	struct submodule_entry key;
	struct submodule key_config;

	hashcpy(key_config.gitmodules_sha1, gitmodules_sha1);
	key_config.path = path;

	hashmap_entry_init(&key, hash);
	key.config = &key_config;

	entry = hashmap_get(&cache->for_path, &key, NULL);
	if (entry)
	return entry->config;
	return NULL;
	}

	static struct submodule cache_lookup_name(struct submodule_cache cache,
	const unsigned char gitmodules_sha1, const char name)
	{
	struct submodule_entry *entry;
	unsigned int hash = hash_sha1_string(gitmodules_sha1, name);
	struct submodule_entry key;
	struct submodule key_config;

	hashcpy(key_config.gitmodules_sha1, gitmodules_sha1);
	key_config.name = name;

	hashmap_entry_init(&key, hash);
	key.config = &key_config;

	entry = hashmap_get(&cache->for_name, &key, NULL);
	if (entry)
	return entry->config;
	return NULL;
	}

	static int name_and_item_from_var(const char var, struct strbuf name,
	struct strbuf *item)
	{
	const char subsection, key;
	int subsection_len, parse;
	parse = parse_config_key(var, "submodule", &subsection,
	&subsection_len, &key);
	if (parse < 0 \|\| !subsection)
	return 0;

	strbuf_add(name, subsection, subsection_len);
	strbuf_addstr(item, key);

	return 1;
	}

	static struct submodule lookup_or_create_by_name(struct submodule_cache cache,
	const unsigned char gitmodules_sha1, const char name)
	{
	struct submodule *submodule;
	struct strbuf name_buf = STRBUF_INIT;

	submodule = cache_lookup_name(cache, gitmodules_sha1, name);
	if (submodule)
	return submodule;

	submodule = xmalloc(sizeof(*submodule));

	strbuf_addstr(&name_buf, name);
	submodule->name = strbuf_detach(&name_buf, NULL);

	submodule->path = NULL;
	submodule->url = NULL;
	submodule->fetch_recurse = RECURSE_SUBMODULES_NONE;
	submodule->ignore = NULL;

	hashcpy(submodule->gitmodules_sha1, gitmodules_sha1);

	cache_add(cache, submodule);

	return submodule;
	}

	static int parse_fetch_recurse(const char opt, const char arg,
	int die_on_error)
	{
	switch (git_config_maybe_bool(opt, arg)) {
	case 1:
	return RECURSE_SUBMODULES_ON;
	case 0:
	return RECURSE_SUBMODULES_OFF;
	default:
	if (!strcmp(arg, "on-demand"))
	return RECURSE_SUBMODULES_ON_DEMAND;

	if (die_on_error)
	die("bad %s argument: %s", opt, arg);
	else
	return RECURSE_SUBMODULES_ERROR;
	}
	}

	int parse_fetch_recurse_submodules_arg(const char opt, const char arg)
	{
	return parse_fetch_recurse(opt, arg, 1);
	}

	static void warn_multiple_config(const unsigned char *commit_sha1,
	const char name, const char option)
	{
	const char *commit_string = "WORKTREE";
	if (commit_sha1)
	commit_string = sha1_to_hex(commit_sha1);
	warning("%s:.gitmodules, multiple configurations found for "
	"'submodule.%s.%s'. Skipping second one!",
	commit_string, name, option);
	}

	struct parse_config_parameter {
	struct submodule_cache *cache;
	const unsigned char *commit_sha1;
	const unsigned char *gitmodules_sha1;
	int overwrite;
	};

	static int parse_config(const char var, const char value, void *data)
	{
	struct parse_config_parameter *me = data;
	struct submodule *submodule;
	struct strbuf name = STRBUF_INIT, item = STRBUF_INIT;
	int ret = 0;

	/* this also ensures that we only parse submodule entries */
	if (!name_and_item_from_var(var, &name, &item))
	return 0;

	submodule = lookup_or_create_by_name(me->cache, me->gitmodules_sha1,
	name.buf);

	if (!strcmp(item.buf, "path")) {
	struct strbuf path = STRBUF_INIT;
	if (!value) {
	ret = config_error_nonbool(var);
	goto release_return;
	}
	if (!me->overwrite && submodule->path != NULL) {
	warn_multiple_config(me->commit_sha1, submodule->name,
	"path");
	goto release_return;
	}

	if (submodule->path)
	cache_remove_path(me->cache, submodule);
	free((void *) submodule->path);
	strbuf_addstr(&path, value);
	submodule->path = strbuf_detach(&path, NULL);
	cache_put_path(me->cache, submodule);
	} else if (!strcmp(item.buf, "fetchrecursesubmodules")) {
	/* when parsing worktree configurations we can die early */
	int die_on_error = is_null_sha1(me->gitmodules_sha1);
	if (!me->overwrite &&
	submodule->fetch_recurse != RECURSE_SUBMODULES_NONE) {
	warn_multiple_config(me->commit_sha1, submodule->name,
	"fetchrecursesubmodules");
	goto release_return;
	}

	submodule->fetch_recurse = parse_fetch_recurse(var, value,
	die_on_error);
	} else if (!strcmp(item.buf, "ignore")) {
	struct strbuf ignore = STRBUF_INIT;
	if (!me->overwrite && submodule->ignore != NULL) {
	warn_multiple_config(me->commit_sha1, submodule->name,
	"ignore");
	goto release_return;
	}
	if (!value) {
	ret = config_error_nonbool(var);
	goto release_return;
	}
	if (strcmp(value, "untracked") && strcmp(value, "dirty") &&
	strcmp(value, "all") && strcmp(value, "none")) {
	warning("Invalid parameter '%s' for config option "
	"'submodule.%s.ignore'", value, var);
	goto release_return;
	}

	free((void *) submodule->ignore);
	strbuf_addstr(&ignore, value);
	submodule->ignore = strbuf_detach(&ignore, NULL);
	} else if (!strcmp(item.buf, "url")) {
	struct strbuf url = STRBUF_INIT;
	if (!value) {
	ret = config_error_nonbool(var);
	goto release_return;
	}
	if (!me->overwrite && submodule->url != NULL) {
	warn_multiple_config(me->commit_sha1, submodule->name,
	"url");
	goto release_return;
	}

	free((void *) submodule->url);
	strbuf_addstr(&url, value);
	submodule->url = strbuf_detach(&url, NULL);
	}

	release_return:
	strbuf_release(&name);
	strbuf_release(&item);

	return ret;
	}

	static int gitmodule_sha1_from_commit(const unsigned char *commit_sha1,
	unsigned char *gitmodules_sha1)
	{
	struct strbuf rev = STRBUF_INIT;
	int ret = 0;

	if (is_null_sha1(commit_sha1)) {
	hashcpy(gitmodules_sha1, null_sha1);
	return 1;
	}

	strbuf_addf(&rev, "%s:.gitmodules", sha1_to_hex(commit_sha1));
	if (get_sha1(rev.buf, gitmodules_sha1) >= 0)
	ret = 1;

	strbuf_release(&rev);
	return ret;
	}

	/* This does a lookup of a submodule configuration by name or by path
	* (key) with on-demand reading of the appropriate .gitmodules from
	* revisions.
	*/
	static const struct submodule config_from(struct submodule_cache cache,
	const unsigned char commit_sha1, const char key,
	enum lookup_type lookup_type)
	{
	struct strbuf rev = STRBUF_INIT;
	unsigned long config_size;
	char *config;
	unsigned char sha1[20];
	enum object_type type;
	const struct submodule *submodule = NULL;
	struct parse_config_parameter parameter;

	/*
	* If any parameter except the cache is a NULL pointer just
	* return the first submodule. Can be used to check whether
	* there are any submodules parsed.
	*/
	if (!commit_sha1 \|\| !key) {
	struct hashmap_iter iter;
	struct submodule_entry *entry;

	hashmap_iter_init(&cache->for_name, &iter);
	entry = hashmap_iter_next(&iter);
	if (!entry)
	return NULL;
	return entry->config;
	}

	if (!gitmodule_sha1_from_commit(commit_sha1, sha1))
	return NULL;

	switch (lookup_type) {
	case lookup_name:
	submodule = cache_lookup_name(cache, sha1, key);
	break;
	case lookup_path:
	submodule = cache_lookup_path(cache, sha1, key);
	break;
	}
	if (submodule)
	return submodule;

	config = read_sha1_file(sha1, &type, &config_size);
	if (!config)
	return NULL;

	if (type != OBJ_BLOB) {
	free(config);
	return NULL;
	}

	/* fill the submodule config into the cache */
	parameter.cache = cache;
	parameter.commit_sha1 = commit_sha1;
	parameter.gitmodules_sha1 = sha1;
	parameter.overwrite = 0;
	git_config_from_buf(parse_config, rev.buf, config, config_size,
	&parameter);
	free(config);

	switch (lookup_type) {
	case lookup_name:
	return cache_lookup_name(cache, sha1, key);
	case lookup_path:
	return cache_lookup_path(cache, sha1, key);
	default:
	return NULL;
	}
	}

	static const struct submodule config_from_path(struct submodule_cache cache,
	const unsigned char commit_sha1, const char path)
	{
	return config_from(cache, commit_sha1, path, lookup_path);
	}

	static const struct submodule config_from_name(struct submodule_cache cache,
	const unsigned char commit_sha1, const char name)
	{
	return config_from(cache, commit_sha1, name, lookup_name);
	}

	static void ensure_cache_init(void)
	{
	if (is_cache_init)
	return;

	cache_init(&cache);
	is_cache_init = 1;
	}

	int parse_submodule_config_option(const char var, const char value)
	{
	struct parse_config_parameter parameter;
	parameter.cache = &cache;
	parameter.commit_sha1 = NULL;
	parameter.gitmodules_sha1 = null_sha1;
	parameter.overwrite = 1;

	ensure_cache_init();
	return parse_config(var, value, &parameter);
	}

	const struct submodule submodule_from_name(const unsigned char commit_sha1,
	const char *name)
	{
	ensure_cache_init();
	return config_from_name(&cache, commit_sha1, name);
	}

	const struct submodule submodule_from_path(const unsigned char commit_sha1,
	const char *path)
	{
	ensure_cache_init();
	return config_from_path(&cache, commit_sha1, path);
	}

	void submodule_free(void)
	{
	cache_free(&cache);
	is_cache_init = 0;
	}