BString, HashString: Replace string hashes with hashdjb2.

headers/private/shared/HashString.h

@@ -1,5 +1,5 @@
 /*
- * Copyright 2004-2007, Ingo Weinhold, [email protected]. All rights reserved.
+ * Copyright 2004-2007, Ingo Weinhold <[email protected]>. All rights reserved.
  * Distributed under the terms of the MIT License.
  */
 #ifndef HASH_STRING_H
@@ -7,29 +7,25 @@
 
 #include <SupportDefs.h>
 
-// string_hash
+
-//
+static inline uint32
-// from the Dragon Book: a slightly modified hashpjw()
+string_hash(const char *_string)
-static inline
-uint32
-string_hash(const char *name)
 {
-	uint32 h = 0;
+	const uint8* string = (const uint8*)_string;
-	if (name) {
+	if (string == NULL)
-		for (; *name; name++) {
+		return 0;
-			uint32 g = h & 0xf0000000;
+
-			if (g)
+	uint32 h = 5381;
-				h ^= g >> 24;
+	char c;
-			h = (h << 4) + *name;
+	while ((c = *string++) != 0)
-		}
+		h = (h * 33) + c;
-	}
 	return h;
 }
 
-#ifdef __cplusplus
 
 namespace BPrivate {
 
+
 // HashString
 class HashString {
 public:
@@ -60,10 +56,11 @@ private:
 	char	*fString;
 };
 
+
 }	// namespace BPrivate
 
+
 using BPrivate::HashString;
 
-#endif	// __cplusplus
 
 #endif	// HASH_STRING_H

src/kits/support/String.cpp

@@ -227,19 +227,17 @@ BString::CountBytes(int32 fromCharOffset, int32 charCount) const
 
 
 /*static*/ uint32
-BString::HashValue(const char* string)
+BString::HashValue(const char* _string)
 {
-	// from the Dragon Book: a slightly modified hashpjw()
+	const uint8* string = (const uint8*)_string;
-    uint32 h = 0;
+	if (string == NULL)
-    if (string != NULL) {
+		return 0;
-        for (; *string; string++) {
+
-            uint32 g = h & 0xf0000000;
+	uint32 h = 5381;
-            if (g)
+	char c;
-                h ^= g >> 24;
+	while ((c = *string++) != 0)
-            h = (h << 4) + *string;
+		h = (h * 33) + c;
-        }
+	return h;
-    }
-    return h;
 }