When logging to a file, redirect fd1 to the log file as well.

[libucw.git] / lib / hashfunc.h

diff --git a/lib/hashfunc.h b/lib/hashfunc.h
index 8e49e4ca3f699d36ede9afb394a59af44a5695fe..cc799476a87938e6349e786c6b6f4d72de9c2df1 100644 (file)
--- a/lib/hashfunc.h
+++ b/lib/hashfunc.h
@@ -1,15 +1,45 @@
 /*
 /*

- *     Sherlock Library -- Hash Functions
+ *     Hyper-super-meta-alt-control-shift extra fast str_len() and hash_*()
+ *     routines

  *
  *

- *     (c) 2002 Martin Mares <mj@ucw.cz>
+ *     (c) 2002, Robert Spalek <robert@ucw.cz>
+ *
+ *     This software may be freely distributed and used according to the terms
+ *     of the GNU Lesser General Public License.

  */
 
 #ifndef _SHERLOCK_HASHFUNC_H
 #define _SHERLOCK_HASHFUNC_H
 
  */
 
 #ifndef _SHERLOCK_HASHFUNC_H
 #define _SHERLOCK_HASHFUNC_H
 

-uns hash_string(byte *x);
-uns hash_string_nocase(byte *x);
-static inline uns hash_int(uns x) { return 6442450967*x; }
-uns hash_block(byte *x, uns len);
+#include "lib/lib.h"
+
+/* An equivalent of the Intel's rol instruction.  */
+#define        ROL(x, bits)    (((x) << (bits)) | ((x) >> (sizeof(uns)*8 - (bits))))
+
+/* The following functions need str to be aligned to uns.  */
+uns str_len_aligned(const byte *str) CONST;
+uns hash_string_aligned(const byte *str) CONST;
+uns hash_block_aligned(const byte *str, uns len) CONST;
+
+#ifdef CPU_ALLOW_UNALIGNED
+#define        str_len(str)            str_len_aligned(str)
+#define        hash_string(str)        hash_string_aligned(str)
+#define        hash_block(str, len)    hash_block_aligned(str, len)
+#else
+uns str_len(const byte *str) CONST;
+uns hash_string(const byte *str) CONST;
+uns hash_block(const byte *str, uns len) CONST;
+#endif
+
+uns hash_string_nocase(const byte *str) CONST;
+
+/*
+ *  We hash integers by multiplying by a reasonably large prime with
+ *  few ones in its binary form (to gave the compiler the possibility
+ *  of using shifts and adds on architectures where multiplication
+ *  instructions are slow).
+ */
+static inline uns CONST hash_int(uns x) { return 0x01008041*x; }
+static inline uns CONST hash_pointer(void *x) { return hash_int((uns)x); }

 
 #endif
 
 #endif