------------------------------------------------------------------------------ -- -- -- GNU ADA RUNTIME LIBRARY (GNARL) COMPONENTS -- -- -- -- S Y S T E M . B I T _ O P S -- -- -- -- S p e c -- -- -- -- Copyright (C) 1992-2004, Free Software Foundation, Inc. -- -- -- -- GNAT is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- -- ware Foundation; either version 2, or (at your option) any later ver- -- -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- -- for more details. You should have received a copy of the GNU General -- -- Public License distributed with GNAT; see file COPYING. If not, write -- -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- -- MA 02111-1307, USA. -- -- -- -- As a special exception, if other files instantiate generics from this -- -- unit, or you link this unit with other files to produce an executable, -- -- this unit does not by itself cause the resulting executable to be -- -- covered by the GNU General Public License. This exception does not -- -- however invalidate any other reasons why the executable file might be -- -- covered by the GNU Public License. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ -- Operations on packed bit strings with System; package System.Bit_Ops is -- Note: in all the following routines, the System.Address parameters -- represent the address of the first byte of an array used to represent -- a packed array (of type System.Unsigned_Types.Packed_Bytes{1,2,4}) -- The length in bits is passed as a separate parameter. procedure Bit_And (Left : System.Address; Llen : Natural; Right : System.Address; Rlen : Natural; Result : System.Address); -- Bitwise "and" of given bit string with result being placed in Result. -- The and operation is allowed to destroy unused bits in the last byte, -- i.e. to leave them set in an undefined manner. Note that Left, Right -- and Result always have the same length in bits (Len). function Bit_Eq (Left : System.Address; Llen : Natural; Right : System.Address; Rlen : Natural) return Boolean; -- Left and Right are the addresses of two bit packed arrays with Llen -- and Rlen being the respective length in bits. The routine compares the -- two bit strings for equality, being careful not to include the unused -- bits in the final byte. Note that the result is always False if Rlen -- is not equal to Llen. procedure Bit_Not (Opnd : System.Address; Len : Natural; Result : System.Address); -- Bitwise "not" of given bit string with result being placed in Result. -- The not operation is allowed to destroy unused bits in the last byte, -- i.e. to leave them set in an undefined manner. Note that Result and -- Opnd always have the same length in bits (Len). procedure Bit_Or (Left : System.Address; Llen : Natural; Right : System.Address; Rlen : Natural; Result : System.Address); -- Bitwise "or" of given bit string with result being placed in Result. -- The or operation is allowed to destroy unused bits in the last byte, -- i.e. to leave them set in an undefined manner. Note that Left, Right -- and Result always have the same length in bits (Len). procedure Bit_Xor (Left : System.Address; Llen : Natural; Right : System.Address; Rlen : Natural; Result : System.Address); -- Bitwise "xor" of given bit string with result being placed in Result. -- The xor operation is allowed to destroy unused bits in the last byte, -- i.e. to leave them set in an undefined manner. Note that Left, Right -- and Result always have the same length in bits (Len). end System.Bit_Ops;