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[PATCH v2 15/19] hashmap: use *_entry APIs for iteration

From
EWEric Wong <e@80x24.org>
Date
Sep 24, 2019, 01:03 UTC
Message-ID
<20190924010324.22619-16-e@80x24.org>
In-Reply-To
<20190924010324.22619-1-e@80x24.org>

Inspired by list_for_each_entry in the Linux kernel. Once again, these are somewhat compromised usability-wise by compilers lacking __typeof__ support.

Signed-off-by: Eric Wong <e@80x24.org>
---
 attr.c                              |  5 +++--
 blame.c                             | 10 ++++++----
 builtin/describe.c                  |  4 ++--
 builtin/difftool.c                  |  8 ++++----
 config.c                            |  5 +++--
 hashmap.c                           |  2 +-
 hashmap.h                           | 15 +++++++++++++--
 merge-recursive.c                   | 25 +++++++++++++++----------
 oidmap.h                            |  6 ++++--
 revision.c                          | 10 ++++++----
 submodule-config.c                  |  8 +++++---
 t/helper/test-hashmap.c             |  7 ++++---
 t/helper/test-lazy-init-name-hash.c | 12 ++++--------
 13 files changed, 70 insertions(+), 47 deletions(-)
diff --git a/attr.c b/attr.c
index 6053481610..ca8be46e8e 100644
--- a/attr.c
+++ b/attr.c
@@ -163,12 +163,13 @@ static void all_attrs_init(struct attr_hashmap *map, struct attr_check *check)
 	if (size != check->all_attrs_nr) {
 		struct attr_hash_entry *e;
 		struct hashmap_iter iter;
-		hashmap_iter_init(&map->map, &iter);
 
 		REALLOC_ARRAY(check->all_attrs, size);
 		check->all_attrs_nr = size;
 
-		while ((e = hashmap_iter_next(&iter))) {
+		hashmap_for_each_entry(&map->map, &iter, e,
+					struct attr_hash_entry,
+					ent /* member name */) {
 			const struct git_attr *a = e->value;
 			check->all_attrs[a->attr_nr].attr = a;
 		}
diff --git a/blame.c b/blame.c
index aa46c7ec52..3d8accf902 100644
--- a/blame.c
+++ b/blame.c
@@ -450,9 +450,9 @@ static int fingerprint_similarity(struct fingerprint *a, struct fingerprint *b)
 	struct hashmap_iter iter;
 	const struct fingerprint_entry *entry_a, *entry_b;
 
-	hashmap_iter_init(&b->map, &iter);
-
-	while ((entry_b = hashmap_iter_next(&iter))) {
+	hashmap_for_each_entry(&b->map, &iter, entry_b,
+				const struct fingerprint_entry,
+				entry /* member name */) {
 		entry_a = hashmap_get_entry(&a->map, entry_b, NULL,
 					struct fingerprint_entry, entry);
 		if (entry_a) {
@@ -473,7 +473,9 @@ static void fingerprint_subtract(struct fingerprint *a, struct fingerprint *b)
 
 	hashmap_iter_init(&b->map, &iter);
 
-	while ((entry_b = hashmap_iter_next(&iter))) {
+	hashmap_for_each_entry(&b->map, &iter, entry_b,
+				const struct fingerprint_entry,
+				entry /* member name */) {
 		entry_a = hashmap_get_entry(&a->map, entry_b, NULL,
 					struct fingerprint_entry, entry);
 		if (entry_a) {
diff --git a/builtin/describe.c b/builtin/describe.c
index e9267b5c9c..8cf2cd992d 100644
--- a/builtin/describe.c
+++ b/builtin/describe.c
@@ -333,8 +333,8 @@ static void describe_commit(struct object_id *oid, struct strbuf *dst)
 		struct commit_name *n;
 
 		init_commit_names(&commit_names);
-		n = hashmap_iter_first(&names, &iter);
-		for (; n; n = hashmap_iter_next(&iter)) {
+		hashmap_for_each_entry(&names, &iter, n, struct commit_name,
+					entry /* member name */) {
 			c = lookup_commit_reference_gently(the_repository,
 							   &n->peeled, 1);
 			if (c)
diff --git a/builtin/difftool.c b/builtin/difftool.c
index 4a37b3edee..dd94179b68 100644
--- a/builtin/difftool.c
+++ b/builtin/difftool.c
@@ -538,8 +538,8 @@ static int run_dir_diff(const char *extcmd, int symlinks, const char *prefix,
 	 * temporary file to both the left and right directories to show the
 	 * change in the recorded SHA1 for the submodule.
 	 */
-	hashmap_iter_init(&submodules, &iter);
-	while ((entry = hashmap_iter_next(&iter))) {
+	hashmap_for_each_entry(&submodules, &iter, entry,
+				struct pair_entry, entry /* member name */) {
 		if (*entry->left) {
 			add_path(&ldir, ldir_len, entry->path);
 			ensure_leading_directories(ldir.buf);
@@ -557,8 +557,8 @@ static int run_dir_diff(const char *extcmd, int symlinks, const char *prefix,
 	 * shows only the link itself, not the contents of the link target.
 	 * This loop replicates that behavior.
 	 */
-	hashmap_iter_init(&symlinks2, &iter);
-	while ((entry = hashmap_iter_next(&iter))) {
+	hashmap_for_each_entry(&symlinks2, &iter, entry,
+				struct pair_entry, entry /* member name */) {
 		if (*entry->left) {
 			add_path(&ldir, ldir_len, entry->path);
 			ensure_leading_directories(ldir.buf);
diff --git a/config.c b/config.c
index 33043ee73c..8433f74371 100644
--- a/config.c
+++ b/config.c
@@ -1942,8 +1942,9 @@ void git_configset_clear(struct config_set *cs)
 	if (!cs->hash_initialized)
 		return;
 
-	hashmap_iter_init(&cs->config_hash, &iter);
-	while ((entry = hashmap_iter_next(&iter))) {
+	hashmap_for_each_entry(&cs->config_hash, &iter, entry,
+				struct config_set_element,
+				ent /* member name */) {
 		free(entry->key);
 		string_list_clear(&entry->value_list, 1);
 	}
diff --git a/hashmap.c b/hashmap.c
index 47934161aa..fd81a389dd 100644
--- a/hashmap.c
+++ b/hashmap.c
@@ -256,7 +256,7 @@ void hashmap_iter_init(struct hashmap *map, struct hashmap_iter *iter)
 	iter->next = NULL;
 }
 
-void *hashmap_iter_next(struct hashmap_iter *iter)
+struct hashmap_entry *hashmap_iter_next(struct hashmap_iter *iter)
 {
 	struct hashmap_entry *current = iter->next;
 	for (;;) {
diff --git a/hashmap.h b/hashmap.h
index a657ab0050..46837ba436 100644
--- a/hashmap.h
+++ b/hashmap.h
@@ -382,16 +382,27 @@ struct hashmap_iter {
 void hashmap_iter_init(struct hashmap *map, struct hashmap_iter *iter);
 
 /* Returns the next hashmap_entry, or NULL if there are no more entries. */
-void *hashmap_iter_next(struct hashmap_iter *iter);
+struct hashmap_entry *hashmap_iter_next(struct hashmap_iter *iter);
 
 /* Initializes the iterator and returns the first entry, if any. */
-static inline void *hashmap_iter_first(struct hashmap *map,
+static inline struct hashmap_entry *hashmap_iter_first(struct hashmap *map,
 		struct hashmap_iter *iter)
 {
 	hashmap_iter_init(map, iter);
 	return hashmap_iter_next(iter);
 }
 
+#define hashmap_iter_next_entry(iter, type, member) \
+	container_of_or_null(hashmap_iter_next(iter), type, member)
+
+#define hashmap_iter_first_entry(map, iter, type, member) \
+	container_of_or_null(hashmap_iter_first(map, iter), type, member)
+
+#define hashmap_for_each_entry(map, iter, var, type, member) \
+	for (var = hashmap_iter_first_entry(map, iter, type, member); \
+		var; \
+		var = hashmap_iter_next_entry(iter, type, member))
+
 /*
  * returns a @pointer of @type matching @keyvar, or NULL if nothing found.
  * @keyvar is a pointer of @type
diff --git a/merge-recursive.c b/merge-recursive.c
index b06e9f7f0b..73c7750448 100644
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -2135,8 +2135,9 @@ static void handle_directory_level_conflicts(struct merge_options *opt,
 	struct string_list remove_from_head = STRING_LIST_INIT_NODUP;
 	struct string_list remove_from_merge = STRING_LIST_INIT_NODUP;
 
-	hashmap_iter_init(dir_re_head, &iter);
-	while ((head_ent = hashmap_iter_next(&iter))) {
+	hashmap_for_each_entry(dir_re_head, &iter, head_ent,
+				struct dir_rename_entry,
+				ent /* member name */) {
 		merge_ent = dir_rename_find_entry(dir_re_merge, head_ent->dir);
 		if (merge_ent &&
 		    !head_ent->non_unique_new_dir &&
@@ -2160,8 +2161,9 @@ static void handle_directory_level_conflicts(struct merge_options *opt,
 	remove_hashmap_entries(dir_re_head, &remove_from_head);
 	remove_hashmap_entries(dir_re_merge, &remove_from_merge);
 
-	hashmap_iter_init(dir_re_merge, &iter);
-	while ((merge_ent = hashmap_iter_next(&iter))) {
+	hashmap_for_each_entry(dir_re_merge, &iter, merge_ent,
+				struct dir_rename_entry,
+				ent /* member name */) {
 		head_ent = dir_rename_find_entry(dir_re_head, merge_ent->dir);
 		if (tree_has_path(opt->repo, merge, merge_ent->dir)) {
 			/* 2. This wasn't a directory rename after all */
@@ -2265,8 +2267,9 @@ static struct hashmap *get_directory_renames(struct diff_queue_struct *pairs)
 	 * we set non_unique_new_dir.  Once we've determined the winner (or
 	 * that there is no winner), we no longer need possible_new_dirs.
 	 */
-	hashmap_iter_init(dir_renames, &iter);
-	while ((entry = hashmap_iter_next(&iter))) {
+	hashmap_for_each_entry(dir_renames, &iter, entry,
+				struct dir_rename_entry,
+				ent /* member name */) {
 		int max = 0;
 		int bad_max = 0;
 		char *best = NULL;
@@ -2624,8 +2627,9 @@ static struct string_list *get_renames(struct merge_options *opt,
 							     entries);
 	}
 
-	hashmap_iter_init(&collisions, &iter);
-	while ((e = hashmap_iter_next(&iter))) {
+	hashmap_for_each_entry(&collisions, &iter, e,
+				struct collision_entry,
+				ent /* member name */) {
 		free(e->target_file);
 		string_list_clear(&e->source_files, 0);
 	}
@@ -2842,8 +2846,9 @@ static void initial_cleanup_rename(struct diff_queue_struct *pairs,
 	struct hashmap_iter iter;
 	struct dir_rename_entry *e;
 
-	hashmap_iter_init(dir_renames, &iter);
-	while ((e = hashmap_iter_next(&iter))) {
+	hashmap_for_each_entry(dir_renames, &iter, e,
+				struct dir_rename_entry,
+				ent /* member name */) {
 		free(e->dir);
 		strbuf_release(&e->new_dir);
 		/* possible_new_dirs already cleared in get_directory_renames */
diff --git a/oidmap.h b/oidmap.h
index 7a939461ff..c66a83ab1d 100644
--- a/oidmap.h
+++ b/oidmap.h
@@ -78,14 +78,16 @@ static inline void oidmap_iter_init(struct oidmap *map, struct oidmap_iter *iter
 
 static inline void *oidmap_iter_next(struct oidmap_iter *iter)
 {
-	return hashmap_iter_next(&iter->h_iter);
+	/* TODO: this API could be reworked to do compile-time type checks */
+	return (void *)hashmap_iter_next(&iter->h_iter);
 }
 
 static inline void *oidmap_iter_first(struct oidmap *map,
 				      struct oidmap_iter *iter)
 {
 	oidmap_iter_init(map, iter);
-	return oidmap_iter_next(iter);
+	/* TODO: this API could be reworked to do compile-time type checks */
+	return (void *)oidmap_iter_next(iter);
 }
 
 #endif
diff --git a/revision.c b/revision.c
index f32fbc5e2e..f28cbe5de8 100644
--- a/revision.c
+++ b/revision.c
@@ -128,9 +128,10 @@ static void paths_and_oids_clear(struct hashmap *map)
 {
 	struct hashmap_iter iter;
 	struct path_and_oids_entry *entry;
-	hashmap_iter_init(map, &iter);
 
-	while ((entry = (struct path_and_oids_entry *)hashmap_iter_next(&iter))) {
+	hashmap_for_each_entry(map, &iter, entry,
+				struct path_and_oids_entry,
+				ent /* member name */) {
 		oidset_clear(&entry->trees);
 		free(entry->path);
 	}
@@ -242,8 +243,9 @@ void mark_trees_uninteresting_sparse(struct repository *r,
 		add_children_by_path(r, tree, &map);
 	}
 
-	hashmap_iter_init(&map, &map_iter);
-	while ((entry = hashmap_iter_next(&map_iter)))
+	hashmap_for_each_entry(&map, &map_iter, entry,
+				struct path_and_oids_entry,
+				ent /* member name */)
 		mark_trees_uninteresting_sparse(r, &entry->trees);
 
 	paths_and_oids_clear(&map);
diff --git a/submodule-config.c b/submodule-config.c
index 5463729ab8..5319933e1d 100644
--- a/submodule-config.c
+++ b/submodule-config.c
@@ -99,8 +99,8 @@ static void submodule_cache_clear(struct submodule_cache *cache)
 	 * allocation of struct submodule entries. Each is allocated by
 	 * their .gitmodules blob sha1 and submodule name.
 	 */
-	hashmap_iter_init(&cache->for_name, &iter);
-	while ((entry = hashmap_iter_next(&iter)))
+	hashmap_for_each_entry(&cache->for_name, &iter, entry,
+				struct submodule_entry, ent /* member name */)
 		free_one_config(entry);
 
 	hashmap_free(&cache->for_path, 1);
@@ -556,7 +556,9 @@ static const struct submodule *config_from(struct submodule_cache *cache,
 		struct hashmap_iter iter;
 		struct submodule_entry *entry;
 
-		entry = hashmap_iter_first(&cache->for_name, &iter);
+		entry = hashmap_iter_first_entry(&cache->for_name, &iter,
+						struct submodule_entry,
+						ent /* member name */);
 		if (!entry)
 			return NULL;
 		return entry->config;
diff --git a/t/helper/test-hashmap.c b/t/helper/test-hashmap.c
index 56846da64c..4ec5e11556 100644
--- a/t/helper/test-hashmap.c
+++ b/t/helper/test-hashmap.c
@@ -222,10 +222,11 @@ int cmd__hashmap(int argc, const char **argv)
 			free(entry);
 
 		} else if (!strcmp("iterate", cmd)) {
-
 			struct hashmap_iter iter;
-			hashmap_iter_init(&map, &iter);
-			while ((entry = hashmap_iter_next(&iter)))
+
+			hashmap_for_each_entry(&map, &iter, entry,
+						struct test_entry,
+						ent /* member name */)
 				printf("%s %s\n", entry->key, get_value(entry));
 
 		} else if (!strcmp("size", cmd)) {
diff --git a/t/helper/test-lazy-init-name-hash.c b/t/helper/test-lazy-init-name-hash.c
index b99a37080d..9d4664d6a4 100644
--- a/t/helper/test-lazy-init-name-hash.c
+++ b/t/helper/test-lazy-init-name-hash.c
@@ -41,17 +41,13 @@ static void dump_run(void)
 			die("non-threaded code path used");
 	}
 
-	dir = hashmap_iter_first(&the_index.dir_hash, &iter_dir);
-	while (dir) {
+	hashmap_for_each_entry(&the_index.dir_hash, &iter_dir, dir,
+				struct dir_entry, ent /* member name */)
 		printf("dir %08x %7d %s\n", dir->ent.hash, dir->nr, dir->name);
-		dir = hashmap_iter_next(&iter_dir);
-	}
 
-	ce = hashmap_iter_first(&the_index.name_hash, &iter_cache);
-	while (ce) {
+	hashmap_for_each_entry(&the_index.name_hash, &iter_cache, ce,
+				struct cache_entry, ent /* member name */)
 		printf("name %08x %s\n", ce->ent.hash, ce->name);
-		ce = hashmap_iter_next(&iter_cache);
-	}
 
 	discard_cache();
 }
Previous: Eric WongNext: Eric Wong
Message 55 of 71 in “hashmap: bugfixes, safety fixes, and WIP improvements”
  1. 00/11 hashmap: bugfixes, safety fixes, and WIP improvementsEric Wong, Aug 26, 2019
  2. 01/11 diff: use hashmap_entry_init on moved_entry.entEric Wong, Aug 26, 2019
  3. Derrick StoleeAug 27, 2019
  4. 02/11 packfile: use hashmap_entry in delta_base_cache_entryEric Wong, Aug 26, 2019
  5. 03/11 hashmap_entry_init takes "struct hashmap_entry *"Eric Wong, Aug 26, 2019
  6. Derrick StoleeAug 27, 2019
  7. Johannes SchindelinAug 28, 2019
  8. Eric WongAug 30, 2019
  9. Johannes SchindelinSep 2, 2019
  10. 04/11 hashmap_entry: detect improper initializationEric Wong, Aug 26, 2019
  11. Johannes SchindelinAug 27, 2019
  12. Eric WongAug 27, 2019
  13. Junio C HamanoAug 27, 2019
  14. Johannes SchindelinAug 28, 2019
  15. Phillip WoodAug 28, 2019
  16. Eric WongAug 30, 2019
  17. 04/11 coccicheck: detect hashmap_entry.hash assignmentEric Wong, Sep 8, 2019
  18. Junio C HamanoSep 9, 2019
  19. 05/11 hashmap_get_next takes "const struct hashmap_entry *"Eric Wong, Aug 26, 2019
  20. 06/11 hashmap_add takes "struct hashmap_entry *"Eric Wong, Aug 26, 2019
  21. 07/11 hashmap_get takes "const struct hashmap_entry *"Eric Wong, Aug 26, 2019
  22. 08/11 hashmap_remove takes "const struct hashmap_entry *"Eric Wong, Aug 26, 2019
  23. 09/11 hashmap_put takes "struct hashmap_entry *"Eric Wong, Aug 26, 2019
  24. 10/11 introduce container_of macroEric Wong, Aug 26, 2019
  25. Derrick StoleeAug 27, 2019
  26. Phillip WoodAug 28, 2019
  27. Eric WongAug 30, 2019
  28. 11/11 hashmap_get_next returns "struct hashmap_entry *"Eric Wong, Aug 26, 2019
  29. Derrick StoleeAug 27, 2019
  30. Eric WongAug 30, 2019
  31. 00/19 hashmap bug/safety/ease-of-use fixesEric Wong, Sep 24, 2019
  32. 01/19 diff: use hashmap_entry_init on moved_entry.entEric Wong, Sep 24, 2019
  33. 02/19 coccicheck: detect hashmap_entry.hash assignmentEric Wong, Sep 24, 2019
  34. Derrick StoleeSep 25, 2019
  35. 03/19 packfile: use hashmap_entry in delta_base_cache_entryEric Wong, Sep 24, 2019
  36. 04/19 hashmap_entry_init takes "struct hashmap_entry *"Eric Wong, Sep 24, 2019
  37. Derrick StoleeSep 25, 2019
  38. 05/19 hashmap_get_next takes "const struct hashmap_entry *"Eric Wong, Sep 24, 2019
  39. 06/19 hashmap_add takes "struct hashmap_entry *"Eric Wong, Sep 24, 2019
  40. 07/19 hashmap_get takes "const struct hashmap_entry *"Eric Wong, Sep 24, 2019
  41. Derrick StoleeSep 25, 2019
  42. Eric WongSep 30, 2019
  43. 08/19 hashmap_remove takes "const struct hashmap_entry *"Eric Wong, Sep 24, 2019
  44. Derrick StoleeSep 25, 2019
  45. 09/19 hashmap_put takes "struct hashmap_entry *"Eric Wong, Sep 24, 2019
  46. 10/19 introduce container_of macroEric Wong, Sep 24, 2019
  47. Derrick StoleeSep 25, 2019
  48. Eric WongSep 30, 2019
  49. 11/19 hashmap_get_next returns "struct hashmap_entry *"Eric Wong, Sep 24, 2019
  50. Derrick StoleeSep 25, 2019
  51. 12/19 hashmap: use *_entry APIs to wrap container_ofEric Wong, Sep 24, 2019
  52. Derrick StoleeSep 25, 2019
  53. 13/19 hashmap_get{,_from_hash} return "struct hashmap_entry *"Eric Wong, Sep 24, 2019
  54. 14/19 hashmap_cmp_fn takes hashmap_entry paramsEric Wong, Sep 24, 2019
  55. 15/19 hashmap: use *_entry APIs for iterationEric Wong, Sep 24, 2019
  56. 16/19 hashmap: hashmap_{put,remove} return hashmap_entry *Eric Wong, Sep 24, 2019
  57. 17/19 hashmap: introduce hashmap_free_entriesEric Wong, Sep 24, 2019
  58. 18/19 OFFSETOF_VAR macro to simplify hashmap iteratorsEric Wong, Sep 24, 2019
  59. Junio C HamanoSep 30, 2019
  60. Junio C HamanoOct 4, 2019
  61. Eric WongOct 4, 2019
  62. Junio C HamanoOct 4, 2019
  63. Eric WongOct 4, 2019
  64. Junio C HamanoOct 6, 2019
  65. 19/19 hashmap: remove type arg from hashmap_{get,put,remove}_entryEric Wong, Sep 24, 2019
  66. Derrick StoleeSep 25, 2019
  67. Derrick StoleeSep 25, 2019
  68. Johannes SchindelinSep 26, 2019
  69. Eric WongSep 30, 2019
  70. Phillip WoodSep 26, 2019
  71. Junio C HamanoSep 29, 2019

Read the whole thread, see it on lore, or plain text.

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