Initial checkin1.5.6

1 files changed, 64 insertions, 0 deletions

diff --git a/include/bit_ops.h b/include/bit_ops.h
new file mode 100644
index 000000000..e10b0e810
--- /dev/null
+++ b/include/bit_ops.h
@@ -0,0 +1,64 @@
+/*************************************************
+* Bit/Word Operations Header File                *
+* (C) 1999-2006 The Botan Project                *
+*************************************************/
+
+#ifndef BOTAN_BIT_OPS_H__
+#define BOTAN_BIT_OPS_H__
+
+#include <botan/types.h>
+
+namespace Botan {
+
+/*************************************************
+* Rotation Functions                             *
+*************************************************/
+template<typename T> inline T rotate_left(T input, u32bit rot)
+   { return (T)((input << rot) | (input >> (8*sizeof(T)-rot))); }
+
+template<typename T> inline T rotate_right(T input, u32bit rot)
+   { return (T)((input >> rot) | (input << (8*sizeof(T)-rot))); }
+
+/*************************************************
+* Byte Extraction Function                       *
+*************************************************/
+template<typename T> inline byte get_byte(u32bit byte_num, T input)
+   { return (byte)(input >> ((sizeof(T)-1-(byte_num&(sizeof(T)-1))) << 3)); }
+
+/*************************************************
+* Byte to Word Conversions                       *
+*************************************************/
+inline u16bit make_u16bit(byte input0, byte input1)
+   { return (u16bit)(((u16bit)input0 << 8) | input1); }
+
+inline u32bit make_u32bit(byte input0, byte input1, byte input2, byte input3)
+   { return (u32bit)(((u32bit)input0 << 24) | ((u32bit)input1 << 16) |
+                     ((u32bit)input2 <<  8) | input3); }
+
+inline u64bit make_u64bit(byte input0, byte input1, byte input2, byte input3,
+                          byte input4, byte input5, byte input6, byte input7)
+   {
+   return (u64bit)(((u64bit)input0 << 56) | ((u64bit)input1 << 48) |
+                   ((u64bit)input2 << 40) | ((u64bit)input3 << 32) |
+                   ((u64bit)input4 << 24) | ((u64bit)input5 << 16) |
+                   ((u64bit)input6 <<  8) | input7);
+   }
+
+/*************************************************
+* XOR Functions                                  *
+*************************************************/
+void xor_buf(byte[], const byte[], u32bit);
+void xor_buf(byte[], const byte[], const byte[], u32bit);
+
+/*************************************************
+* Misc Utility Functions                         *
+*************************************************/
+bool power_of_2(u64bit);
+u32bit high_bit(u64bit);
+u32bit low_bit(u64bit);
+u32bit significant_bytes(u64bit);
+u32bit hamming_weight(u64bit);
+
+}
+
+#endif