libhmap-c

commit a21f5271c522c5938d96af8218d3f24ff85401d9
parent a7042dfef6c4329776d0523bddb8c8c2288cc92c
Author: Louis Burda <quent.burda@gmail.com>
Date:   Mon, 20 Mar 2023 14:53:06 +0100

Zero-cost immediate storage for types with size < sizeof(void *)

Diffstat:
M
include/hashmap.h
 | 
22
+++++++++++++++++-----
M
src/hashmap.c
 | 
10
++++++----
M
src/test.c
 | 
10
++++------

3 files changed, 27 insertions(+), 15 deletions(-)
diff --git a/include/hashmap.h b/include/hashmap.h
@@ -20,10 +20,20 @@ enum {
 	HMAP_KEY_MISSING,
 };
 
+struct hashmap_val {
+	union {
+		char c;
+		float f;
+		int i;
+		unsigned int u;
+		void *p;
+	};
+};
+
 struct hashmap_link {
 	void *key;
 	size_t keysize;
-	void *value;
+	struct hashmap_val value;
 	struct hashmap_link *next;
 };
 
@@ -59,15 +69,17 @@ struct hashmap_link **hashmap_link_pos(struct hashmap *map,
 struct hashmap_link *hashmap_link_pop(struct hashmap *map,
 	const void *key, size_t size);
 void hashmap_link_set(struct hashmap *map, struct hashmap_link *link,
-	void *key, size_t keysize, void *value);
+	void *key, size_t keysize, struct hashmap_val value);
 int hashmap_link_alloc(struct hashmap *map, struct hashmap_link **out,
-	void *key, size_t keysize, void *value);
+	void *key, size_t keysize, struct hashmap_val value);
 
 struct hashmap_link *hashmap_get(struct hashmap *map,
 	const void *key, size_t size);
 void hashmap_rm(struct hashmap *map, const void *key, size_t size);
-int hashmap_set(struct hashmap *map, void *key, size_t keysize, void *value);
-int hashmap_add(struct hashmap *map, void *key, size_t keysize, void *value);
+int hashmap_set(struct hashmap *map, void *key, size_t keysize,
+	struct hashmap_val value);
+int hashmap_add(struct hashmap *map, void *key, size_t keysize,
+	struct hashmap_val value);
 
 void hashmap_iter_init(struct hashmap_iter *iter);
 bool hashmap_iter_next(const struct hashmap *map, struct hashmap_iter *iter);
diff --git a/src/hashmap.c b/src/hashmap.c
@@ -153,7 +153,7 @@ hashmap_link_pop(struct hashmap *map, const void *key, size_t keysize)
 
 void
 hashmap_link_set(struct hashmap *map, struct hashmap_link *link,
-	void *key, size_t keysize, void *value)
+	void *key, size_t keysize, struct hashmap_val value)
 {
 	link->key = key;
 	link->keysize = keysize;
@@ -162,7 +162,7 @@ hashmap_link_set(struct hashmap *map, struct hashmap_link *link,
 
 int
 hashmap_link_alloc(struct hashmap *map, struct hashmap_link **out,
-	void *key, size_t keysize, void *value)
+	void *key, size_t keysize, struct hashmap_val value)
 {
 	struct hashmap_link *link;
 	int rc;
@@ -199,7 +199,8 @@ hashmap_rm(struct hashmap *map, const void *key, size_t keysize)
 }
 
 int
-hashmap_set(struct hashmap *map, void *key, size_t keysize, void *value)
+hashmap_set(struct hashmap *map, void *key, size_t keysize,
+	struct hashmap_val value)
 {
 	struct hashmap_link **iter;
 
@@ -212,7 +213,8 @@ hashmap_set(struct hashmap *map, void *key, size_t keysize, void *value)
 }
 
 int
-hashmap_add(struct hashmap *map, void *key, size_t keysize, void *value)
+hashmap_add(struct hashmap *map, void *key, size_t keysize,
+	struct hashmap_val value)
 {
 	struct hashmap_link **iter;
 	int rc;
diff --git a/src/test.c b/src/test.c
@@ -12,7 +12,7 @@ main(int argc, const char **argv)
 {
 	struct hashmap hashmap;
 	struct hashmap_iter iter;
-	void *key, *value;
+	void *key;
 	int i, rc;
 
 	rc = hashmap_init(&hashmap, 10, hashmap_str_hasher,
@@ -21,16 +21,14 @@ main(int argc, const char **argv)
 
 	for (i = 1; i < argc; i++) {
 		key = strdup(argv[i]);
-		value = malloc(sizeof(int));
-		memcpy(value, &i, sizeof(int));
-		rc = hashmap_set(&hashmap, key, strlen(key) + 1,
-			value, sizeof(int));
+		rc = hashmap_add(&hashmap, key, strlen(key) + 1,
+			(struct hashmap_val) {.i = i});
 		if (rc) LIBHASHMAP_ERR(rc);
 	}
 
 	for (HASHMAP_ITER(&hashmap, &iter)) {
 		printf("%s: %i\n", (char *)iter.link->key,
-			*(int*)iter.link->value);
+			iter.link->value.i);
 	}
 
 	hashmap_deinit(&hashmap);