Finished hash table

SLS_C/include/sls/hash_table.h

@@ -11,7 +11,8 @@
 #include "sls/string.h"
 
 typedef struct Bucket {
-    uint32_t key_hash_b;
+    uint32_t hash_a;
+    uint32_t hash_b;
     void *item;
     struct Bucket *next;
 } Bucket;

SLS_C/src/hash_table.c

@@ -16,39 +16,34 @@ static size_t next_power_of_two(size_t n) {
     n |= n >> 4;
     n |= n >> 8;
     n |= n >> 16;
-#if SIZE_MAX > UINT32_MAX
+    #if SIZE_MAX > UINT32_MAX
         n |= n >> 32;
-#endif
+    #endif
     n++;
     return n;
 }
 
 HashTable *init_hash_table(size_t min_buckets_count) {
-    HashTable *ht = (HashTable *)malloc(sizeof(HashTable));
+    size_t buckets_count = next_power_of_two(min_buckets_count);
+    size_t size = sizeof(HashTable) + buckets_count * sizeof(Bucket);
+    HashTable *ht = (HashTable *)malloc(size);
     if (!ht) return NULL;
-
-    ht->buckets_count = next_power_of_two(min_buckets_count);
-
-    ht->buckets = (Bucket **)calloc(ht->buckets_count, sizeof(Bucket *));
-    if (!ht->buckets) {
-        free(ht);
-        return NULL;
-    }
-
+    ht->buckets_count = buckets_count;
+    for (size_t i = 0; i < buckets_count; i++)
+        ht->buckets[i] = NULL;
     return ht;
 }
 
 void del_hash_table(HashTable *ht) {
     for (size_t i = 0; i < ht->buckets_count; i++) {
-        Bucket *next, *head;
-        head = (ht->buckets)+i;
+        Bucket *head = ht->buckets[i];
         while (head) {
-            next = head->next;
+            Bucket *next = head->next;
+            // TODO: Does item need to be freed?
             free(head);
             head = next;
         }
     }
-    free(ht->buckets);
     free(ht);
 }
 
@@ -84,12 +79,13 @@ static inline uint32_t sls_hash_b(SlsStr key) {
         key.len -= 4;
     }
 
-    switch (key.len) {
-        case 3: hash ^= key.str[2] << 16;
-        case 2: hash ^= key.str[1] << 8;
-        case 1: hash ^= key.str[0];
+    if (key.len >= 3)
+        hash ^= key.str[2] << 16;
+    if (key.len >= 2)
+        hash ^= key.str[1] << 8;
+    if (key.len >= 1)
+        hash ^= key.str[0];
     hash *= m;
-    }
 
     hash ^= hash >> 13;
     hash *= m;
@@ -98,12 +94,62 @@ static inline uint32_t sls_hash_b(SlsStr key) {
     return hash;
 }
 
-static inline size_t bucket_index(const HashTable *ht, SlsStr key) {
-    return sls_hash_a(key) & (ht->buckets_count - 1);
+Boolean hash_table_put(HashTable *ht, SlsStr key, void *item) {
+    uint32_t hash_a = sls_hash_a(key);
+    uint32_t hash_b = sls_hash_b(key);
+    size_t bucket_index = hash_a & (ht->buckets_count - 1);
+
+    for (Bucket *node = ht->buckets[bucket_index]; node; node = node->next) {
+        if (node->hash_a == hash_a && node->hash_b == hash_b) {
+            // TODO: Does item need to be freed before being replaced?
+            node->item = item;
+            return TRUE;
+        }
+    }
+
+    Bucket *bucket = (Bucket *)malloc(sizeof(Bucket));
+    if (!bucket)
+        return FALSE;
+    bucket->hash_a = hash_a;
+    bucket->hash_b = hash_b;
+    bucket->item = item;
+    bucket->next = ht->buckets[bucket_index];
+    ht->buckets[bucket_index] = bucket;
+
+    return TRUE;
 }
 
-Boolean hash_table_put(HashTable *ht, SlsStr key, void *item);
+void *hash_table_get(const HashTable *ht, SlsStr key, void *default_item) {
+    uint32_t hash_a = sls_hash_a(key);
+    uint32_t hash_b = sls_hash_b(key);
+    size_t bucket_index = hash_a & (ht->buckets_count - 1);
 
-void *hash_table_get(const HashTable *ht, SlsStr key, void *default_item);
+    for (Bucket *node = ht->buckets[bucket_index]; node; node = node->next)
+        if (node->hash_a == hash_a && node->hash_b == hash_b)
+            return node->item;
 
-Boolean hash_table_del(HashTable *ht, SlsStr key);
+    return default_item;
+}
+
+Boolean hash_table_del(HashTable *ht, SlsStr key) {
+    uint32_t hash_a = sls_hash_a(key);
+    uint32_t hash_b = sls_hash_b(key);
+    size_t bucket_index = hash_a & (ht->buckets_count - 1);
+
+    Bucket *prev = NULL;
+
+    for (Bucket *node = ht->buckets[bucket_index]; node; node = node->next) {
+        if (node->hash_a == hash_a && node->hash_b == hash_b) {
+            if (prev == NULL)
+                ht->buckets[bucket_index] = node->next;
+            else
+                prev->next = node->next;
+            // TODO: Does item need to be freed?
+            free(node);
+            return TRUE;
+        }
+        prev = node;
+    }
+
+    return FALSE;
+}