Add hashing.

src/Makefile

@@ -9,6 +9,7 @@ SRCS = array.c	\
        string.c
 
 INCLUDES = ${SRCS:.c=.h}	\
-	   corefw.h
+	   corefw.h		\
+	   hash.h
 
 include ../buildsys.mk

src/array.c

@@ -29,6 +29,7 @@
 
 #include "object.h"
 #include "array.h"
+#include "hash.h"
 
 struct CFWArray {
 	CFWObject obj;
@@ -88,6 +89,23 @@ equal(void *ptr1, void *ptr2)
 	return true;
 }
 
+static uint32_t
+hash(void *ptr)
+{
+	CFWArray *array = ptr;
+	size_t i;
+	uint32_t hash;
+
+	CFW_HASH_INIT(hash);
+
+	for (i = 0; i < array->size; i++)
+		CFW_HASH_ADD_HASH(hash, cfw_hash(array->data[i]));
+
+	CFW_HASH_FINALIZE(hash);
+
+	return hash;
+}
+
 static void*
 copy(void *ptr)
 {
@@ -258,6 +276,7 @@ static CFWClass class = {
 	.ctor = ctor,
 	.dtor = dtor,
 	.equal = equal,
+	.hash = hash,
 	.copy = copy
 };
 CFWClass *cfw_array = &class;

src/class.h

@@ -29,6 +29,7 @@
 
 #include <stddef.h>
 #include <stdbool.h>
+#include <stdint.h>
 #include <stdarg.h>
 
 typedef struct CFWClass {
@@ -37,6 +38,7 @@ typedef struct CFWClass {
 	bool (*ctor)(void*, va_list args);
 	void (*dtor)(void*);
 	bool (*equal)(void*, void*);
+	uint32_t (*hash)(void*);
 	void* (*copy)(void*);
 } CFWClass;
 

src/hash.h

@@ -0,0 +1,52 @@
+/*
+ * Copyright (c) 2012, Jonathan Schleifer <js@webkeks.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __COREFW_HASH_H__
+#define __COREFW_HASH_H__
+
+#define CFW_HASH_INIT(hash) hash = 0
+#define CFW_HASH_ADD(hash, byte)	\
+	{				\
+		hash += (uint8_t)byte;	\
+		hash += (hash << 10);	\
+		hash ^= (hash >> 6);	\
+	}
+#define CFW_HASH_FINALIZE(hash)		\
+	{				\
+		hash += (hash << 3);	\
+		hash ^= (hash >> 11);	\
+		hash += (hash << 15);	\
+	}
+#define CFW_HASH_ADD_HASH(hash, other_)				\
+	{							\
+		uint32_t other = other_;			\
+		CFW_HASH_ADD(hash, (other >> 24) & 0xFF);	\
+		CFW_HASH_ADD(hash, (other >> 16) & 0xFF);	\
+		CFW_HASH_ADD(hash, (other >>  8) & 0xFF);	\
+		CFW_HASH_ADD(hash, other & 0xFF);		\
+	}
+
+#endif

src/object.c

@@ -95,6 +95,17 @@ cfw_equal(void *ptr1, void *ptr2)
 		return (obj1 == obj2);
 }
 
+uint32_t
+cfw_hash(void *ptr)
+{
+	CFWObject *obj = ptr;
+
+	if (obj->cls->hash != NULL)
+		return obj->cls->hash(obj);
+
+	return (uint32_t)(uintptr_t)ptr;
+}
+
 void*
 cfw_copy(void *ptr)
 {
@@ -102,7 +113,7 @@ cfw_copy(void *ptr)
 
 	if (obj->cls->copy != NULL)
 		return obj->cls->copy(obj);
-	else
+
 	return NULL;
 }
 

src/object.h

@@ -40,6 +40,7 @@ extern void* cfw_ref(void*);
 extern void cfw_unref(void*);
 extern void cfw_free(void*);
 extern bool cfw_equal(void*, void*);
+extern uint32_t cfw_hash(void*);
 extern void* cfw_copy(void*);
 
 #endif

src/string.c

@@ -30,6 +30,7 @@
 
 #include "object.h"
 #include "string.h"
+#include "hash.h"
 
 struct CFWString {
 	CFWObject obj;
@@ -83,6 +84,23 @@ equal(void *ptr1, void *ptr2)
 	return !memcmp(str1->data, str2->data, str1->len);
 }
 
+static uint32_t
+hash(void *ptr)
+{
+	CFWString *str = ptr;
+	size_t i;
+	uint32_t hash;
+
+	CFW_HASH_INIT(hash);
+
+	for (i = 0; i < str->len; i++)
+		CFW_HASH_ADD(hash, str->data[i]);
+
+	CFW_HASH_FINALIZE(hash);
+
+	return hash;
+}
+
 static void*
 copy(void *ptr)
 {
@@ -177,6 +195,7 @@ static CFWClass class = {
 	.ctor = ctor,
 	.dtor = dtor,
 	.equal = equal,
+	.hash = hash,
 	.copy = copy
 };
 CFWClass *cfw_string = &class;