freepascal.compiler/packages/extra/palmunits/netbitutils.pp

{$MACRO ON}

(******************************************************************************
 *
 * Copyright (c) 1997-2000 Palm, Inc. or its subsidiaries.
 * All rights reserved.
 *
 * File: NetBitUtils.h
 *
 * Release: Palm OS SDK 4.0 (63220)
 *
 * Description:
 *   Header file for bit manipulation routines used primarily
 * by wireless network protocols.
 *
 *   These routines live in the NetLib but are broken out here into
 * a separate header so that they can be more easily used by source
 * files that don't need access to the other NetLib functions.
 *
 * History:
 *    6/11/97  Created by Ron Marianetti
 * Name  Date     Description
 * ----  ----     -----------
 * vmk      8/25/98     Defined bitVarIntMaxBits and bitVarIntMaxBytes
 *
 *****************************************************************************)

unit netbitutils;

interface

uses  palmos, netmgr;

// # of bits in a byte
const
  bitsInByte = 8;

// Maximum size of variable-size ints in # of bits and bytes.  This is based on
// the largest variable size int, which is encoded as follows: 1111  Bit[32]
  bitVarIntMaxBits       = 36;

// #define bitVarIntMaxBytes  ((bitVarIntMaxBits + bitsInByte - 1) / bitsInByte)

//=====================================================
// BitXXX Macros
//
// The following macros are handy because they don't require that
//  the source code pass in the NetLib library refnum to every
//  call.
//
// When building server code or other emulation code where th
//   library trap dispatcher is not used, the libRefNUm is unused
//  and can be 0.
//
// When building for the viewer, the libRefNum must be the refNum
//  of the NetLib. For applications, this libRefNum must be put
//  into an application global named 'AppNetRefnum'.
//
//====================================================

(*
#if USE_TRAPS == 0
   #define  netPrvRefnum 0
#else
   #define  netPrvRefnum AppNetRefnum
#endif
*)

(*
#define  BitMove( dstP,  dstBitOffsetP, srcP,  srcBitOffsetP, numBits)  \
   NetLibBitMove(netPrvRefnum, dstP, dstBitOffsetP, srcP, srcBitOffsetP, numBits)

#define  BitPutFixed( dstP,  dstBitOffsetP, value,  numBits)   \
   NetLibBitPutFixed(netPrvRefnum, dstP,  dstBitOffsetP, value,  numBits)

#define  BitGetFixed(srcP, srcBitOffsetP, numBits) \
   NetLibBitGetFixed(netPrvRefnum, srcP, srcBitOffsetP, numBits)

#define  BitPutUIntV(dstP, dstBitOffsetP, value)   \
   NetLibBitPutUIntV(netPrvRefnum, dstP, dstBitOffsetP, value)

#define  BitGetUIntV(srcP, srcBitOffsetP) \
   NetLibBitGetUIntV(netPrvRefnum, srcP, srcBitOffsetP)

#define  BitPutIntV(dstP, dstBitOffsetP,  value) \
   NetLibBitPutIntV(netPrvRefnum, dstP, dstBitOffsetP, value)

#define  BitGetIntV(srcP, srcBitOffsetP)  \
   NetLibBitGetIntV(netPrvRefnum, srcP, srcBitOffsetP)
*)

//=====================================================
// Macros that convert native integers to and from
//  big-endian (network) order which is the order used to store
//  variable length integers by the BitMove utilities.
//====================================================

(*
#if CPU_TYPE == CPU_x86

#define _NetSwap16(x) \
   ((((x) >> 8) & 0xFF) | \
    (((x) & 0xFF) << 8))

#define _NetSwap32(x) \
   ((((x) >> 24) & 0x00FF) | \
    (((x) >>  8) & 0xFF00) | \
    (((x) & 0xFF00) <<  8) | \
    (((x) & 0x00FF) << 24))

#define NetHToNS(x)  _NetSwap16(x)
#define NetHToNL(x)  _NetSwap32(x)
#define NetNToHS(x)  _NetSwap16(x)
#define NetNToHL(x)  _NetSwap32(x)

#elif CPU_TYPE == CPU_68K

#define NetHToNS(x)  (x)
#define NetHToNL(x)  (x)
#define NetNToHS(x)  (x)
#define NetNToHL(x)  (x)

#else
// We'll define these macros for any other architectures needed as we come
// across them.
#endif
*)

//=====================================================
// Functions
//====================================================

//--------------------------------------------------
// Bit Moving functions. For "slim" bit packing protocols
// used over wireless.
//--------------------------------------------------
procedure NetLibBitMove(libRefNum: UInt16; var dstP: UInt8; var dstBitOffsetP: UInt32;
                        var srcP: UInt8; var srcBitOffsetP: UInt32; numBits: UInt32); syscall netLibTrapBitMove;

procedure NetLibBitPutFixed(libRefNum: UInt16; var dstP: UInt8; var dstBitOffsetP: UInt32;
                            value: UInt32; numBits: UInt16); syscall netLibTrapBitPutFixed;

function NetLibBitGetFixed(libRefNum: UInt16; var dstP: UInt8; var dstBitOffsetP: UInt32;
                           numBits: UInt16): UInt32; syscall netLibTrapBitGetFixed;

procedure NetLibBitPutUIntV(libRefNum: UInt16; var dstP: UInt8; var dstBitOffsetP: UInt32;
                            value: UInt32); syscall netLibTrapBitPutUIntV;

function NetLibBitGetUIntV(libRefNum: UInt16; var dstP: UInt8; var dstBitOffsetP: UInt32): UInt32; syscall netLibTrapBitGetUIntV;

procedure NetLibBitPutIntV(libRefNum: UInt16; var dstP: UInt8; var dstBitOffsetP: UInt32;
                           value: Int32); syscall netLibTrapBitPutUIntV;

function NetLibBitGetIntV(libRefNum: UInt16; var dstP: UInt8; var dstBitOffsetP: UInt32): Int32; syscall netLibTrapBitGetUIntV;

implementation

end.