diff --git a/hashtable.c b/hashtable.c
index 244b453..a48c7b2 100644
--- a/hashtable.c
+++ b/hashtable.c
@@ -4,6 +4,19 @@
 #include "sdbm.h"
 #include "hashtable.h"
 
+bool streq(char* str1, size_t len1, char* str2, size_t len2) {
+	if        (len1 == 0 && len2 == 0) {
+		return !strcmp(str1, str2);
+	} else if (len1 == len2) {
+		return !memcmp(str1, str2, len1);
+	} else if (len1 == 0) {
+		return !memcmp(str1, str2, len2);
+	} else if (len2 == 0) {
+		return !memcmp(str1, str2, len1);
+	}
+	return true;
+}
+
 bool hashtable_recreate(hashtable* table) {
 	size_t oldcapacity = table->capacity;
 	hashtable_item* olditems = table->items;
@@ -17,7 +30,7 @@ bool hashtable_recreate(hashtable* table) {
 	for (size_t i = 0; i < oldcapacity; i++) {
 		if (olditems[i].name == NULL || olditems[i].name == (void*)1)
 			continue;
-		size_t_optional index = hashtable_insert(&temptable, olditems[i].name);
+		size_t_optional index = hashtable_insert(&temptable, olditems[i].name, olditems[i].size);
 		if (!index.exists) {
 			hashtable_item* array = temptable.items;
 			for (size_t i = 0; i < temptable.capacity; i++)
@@ -42,21 +55,29 @@ hashtable* hashtable_create(void) {
 	return table;
 }
 
-size_t_optional hashtable_key(hashtable* table, char* name) {
-	size_t index = sdbm(name) & (table->capacity - 1);
+size_t_optional hashtable_key(hashtable* table, char* name, size_t size) {
+	size_t index;
+	if (size)
+		index = sdbm_clean(name, size) & (table->capacity - 1);
+	else
+		index = sdbm(name) & (table->capacity - 1);
 	hashtable_item* array = table->items;
 	while (1) {
 		if (array[index].name == NULL) 
 			return (size_t_optional) { false, 0 }; 
 		if (array[index].name != (void*)(1))
-			if (!strcmp(name, array[index].name))
+			if (streq(name, size, array[index].name, array[index].size))
 				return (size_t_optional) { true, index };
 		index = (index + 1) & (table->capacity - 1);
 	}
 }
 
-size_t_optional hashtable_insert(hashtable* table, char* name) {
-	size_t index = sdbm(name) & (table->capacity - 1);
+size_t_optional hashtable_insert(hashtable* table, char* name, size_t size) {
+	size_t index;
+	if (size)
+		index = sdbm_clean(name, size) & (table->capacity - 1);
+	else
+		index = sdbm(name) & (table->capacity - 1);
 	hashtable_item* array = table->items;
 	if ((table->capacity >> 2) * 3 < table->filled) {
 		hashtable_recreate(table);
@@ -64,12 +85,16 @@ size_t_optional hashtable_insert(hashtable* table, char* name) {
 	while (1) {
 		if (array[index].name == NULL || array[index].name == (void*)1) {
 			array[index].name = malloc(strlen(name) + sizeof(name));
-			strcpy(array[index].name, name);
+			array[index].size = size;
+			if (size)
+				memcpy(array[index].name, name, size);
+			else
+				strcpy(array[index].name, name);
 			table->filled++;
 			return (size_t_optional) {true, index};
 		}
 		else
-			if (!strcmp(array[index].name, name))
+			if (streq(array[index].name, array[index].size, name, size))
 				return (size_t_optional) {true, index};
 			else
 				index = (index + 1) & (table->capacity - 1);
@@ -83,21 +108,21 @@ void hashtable_destroy(hashtable* table) {
 	free(table);
 }
 
-void* hashtable_get(hashtable* table, char* name) {
-	size_t_optional index = hashtable_key(table, name);
+void* hashtable_get(hashtable* table, char* name, size_t size) {
+	size_t_optional index = hashtable_key(table, name, size);
 	if (!index.exists)
 		return NULL;
 	return table->items[index.sizet].data;
 }
 
-void hashtable_set(hashtable* table, char* name, void* data) {
-	size_t_optional index = hashtable_insert(table, name);
+void hashtable_set(hashtable* table, char* name, size_t size, void* data) {
+	size_t_optional index = hashtable_insert(table, name, size);
 	if (index.exists)
 		table->items[index.sizet].data = data;
 }
 
-bool hashtable_delete(hashtable* table, char* name) {
-	size_t_optional index = hashtable_key(table, name);
+bool hashtable_delete(hashtable* table, char* name, size_t size) {
+	size_t_optional index = hashtable_key(table, name, size);
 	if (index.exists) {
 		table->items[index.sizet].name = (void*)1;
 		table->filled--;
@@ -106,9 +131,9 @@ bool hashtable_delete(hashtable* table, char* name) {
 		return false;
 }
 
-void hashtable_forall(hashtable* table, void (*callback)(char*, void*, void*), void* userdata) {
+void hashtable_forall(hashtable* table, void (*callback)(char*, size_t, void*, void*), void* userdata) {
 	size_t capacity = table->capacity;
 	hashtable_item* items = table->items;
 	for (size_t i = 0; i < capacity; i++)
-		callback(items[i].name, items[i].data, userdata);
+		callback(items[i].name, items[i].size, items[i].data, userdata);
 }
diff --git a/hashtable.h b/hashtable.h
index b866665..ac7405a 100644
--- a/hashtable.h
+++ b/hashtable.h
@@ -1,12 +1,16 @@
 #include <stdlib.h>
 #include <stdbool.h>
 
+#ifndef HASHTABLE_H
+#define HASHTABLE_H
+
 typedef struct {
 	bool exists;
 	size_t sizet;
 } size_t_optional;
 
 typedef struct {
+	size_t size;
 	char* name;
 	void* data;
 } hashtable_item;
@@ -23,14 +27,16 @@ hashtable* hashtable_create(void);
 
 void hashtable_destroy(hashtable*);
 
-size_t_optional hashtable_key(hashtable*, char*);
+size_t_optional hashtable_key(hashtable*, char*, size_t);
 
-size_t_optional hashtable_insert(hashtable*, char*);
+size_t_optional hashtable_insert(hashtable*, char*, size_t);
 
-void* hashtable_get(hashtable* table, char* name);
+void* hashtable_get(hashtable* table, char* name, size_t);
 
-void hashtable_set(hashtable* table, char* name, void* data);
+void hashtable_set(hashtable* table, char* name, size_t, void* data);
 
-bool hashtable_delete(hashtable*, char*);
+bool hashtable_delete(hashtable*, char*, size_t);
 
-void hashtable_forall(hashtable*, void (*)(char*, void*, void*), void*);
+void hashtable_forall(hashtable*, void (*)(char*, size_t, void*, void*), void*);
+
+#endif
diff --git a/sdbm.c b/sdbm.c
deleted file mode 100644
index 3715a0f..0000000
--- a/sdbm.c
+++ /dev/null
@@ -1,8 +0,0 @@
-unsigned long sdbm(char *str) {
-    unsigned long hash = 0;
-
-    for (int c = *str; c != 0; c = *str++)
-        hash = c + (hash << 6) + (hash << 16) - hash;
-
-    return hash;
-}
diff --git a/sdbm.h b/sdbm.h
index bfe3187..71f27de 100644
--- a/sdbm.h
+++ b/sdbm.h
@@ -1 +1,23 @@
-unsigned long sdbm(char *str);
+#include <stdlib.h>
+#ifndef SDBM_H
+#define SDBM_H
+#include <stdlib.h>
+
+static unsigned long sdbm(char *str) {
+    unsigned long hash = 0;
+
+    for (int c = *str; c != 0; c = *str++)
+        hash = c + (hash << 6) + (hash << 16) - hash;
+
+    return hash;
+}
+
+static unsigned long sdbm_clean(char *str, size_t size) {
+    unsigned long hash = 0;
+
+    for (size_t i = 0; i < size + 1; i++)
+        hash = *str + (hash << 6) + (hash << 16) - hash;
+
+    return hash;
+}
+#endif