Handy macros for byte operations as well as set and get bits

gistfile1.c

/**************************************************************************************************
 * Filename:       hal_defs.h
 * Description:    This file contains useful macros and data types
 *
 *
 * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com/ 
 * 
 * 
 *  Redistribution and use in source and binary forms, with or without 
 *  modification, are permitted provided that the following conditions 
 *  are met:
 *
 *    Redistributions of source code must retain the above copyright 
 *    notice, this list of conditions and the following disclaimer.
 *
 *    Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the 
 *    documentation and/or other materials provided with the   
 *    distribution.
 *
 *    Neither the name of Texas Instruments Incorporated nor the names of
 *    its contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
 *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
 *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 *  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 
 *  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
 *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
 *  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
 *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
 *  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */
#ifndef HAL_DEFS_H
#define HAL_DEFS_H

#include <stdint.h>
/* ------------------------------------------------------------------------------------------------
 *                                             Macros
 * ------------------------------------------------------------------------------------------------
 */

#ifndef BV
#define BV(n)      (1 << (n))
#endif

#ifndef BF
#define BF(x,b,s)  (((x) & (b)) >> (s))
#endif

#ifndef MIN
#define MIN(n,m)   (((n) < (m)) ? (n) : (m))
#endif

#ifndef MAX
#define MAX(n,m)   (((n) < (m)) ? (m) : (n))
#endif

#ifndef ABS
#define ABS(n)     (((n) < 0) ? -(n) : (n))
#endif


/* takes a byte out of a uint32_t : var - uint32_t,  ByteNum - byte to take out (0 - 3) */
#define BREAK_UINT32( var, ByteNum ) \
          (uint8_t)((uint32_t)(((var) >>((ByteNum) * 8)) & 0x00FF))

#define BUILD_UINT32(Byte0, Byte1, Byte2, Byte3) \
          ((uint32_t)((uint32_t)((Byte0) & 0x00FF) \
          + ((uint32_t)((Byte1) & 0x00FF) << 8) \
          + ((uint32_t)((Byte2) & 0x00FF) << 16) \
          + ((uint32_t)((Byte3) & 0x00FF) << 24)))

#define BUILD_UINT16(loByte, hiByte) \
          ((uint16_t)(((loByte) & 0x00FF) + (((hiByte) & 0x00FF) << 8)))

#define HI_UINT16(a) (((a) >> 8) & 0xFF)
#define LO_UINT16(a) ((a) & 0xFF)

#define BUILD_UINT8(hiByte, loByte) \
          ((uint8_t)(((loByte) & 0x0F) + (((hiByte) & 0x0F) << 4)))

#define HI_UINT8(a) (((a) >> 4) & 0x0F)
#define LO_UINT8(a) ((a) & 0x0F)

#ifndef GET_BIT
#define GET_BIT(DISCS, IDX)  (((DISCS)[((IDX) / 8)] & BV((IDX) % 8)) ? TRUE : FALSE)
#endif
#ifndef SET_BIT
#define SET_BIT(DISCS, IDX)  (((DISCS)[((IDX) / 8)] |= BV((IDX) % 8)))
#endif
#ifndef CLR_BIT
#define CLR_BIT(DISCS, IDX)  (((DISCS)[((IDX) / 8)] &= (BV((IDX) % 8) ^ 0xFF)))
#endif

/*
 *  This macro is for use by other macros to form a fully valid C statement.
 *  Without this, the if/else conditionals could show unexpected behavior.
 *
 *  For example, use...
 *    #define SET_REGS()  st( ioreg1 = 0; ioreg2 = 0; )
 *  instead of ...
 *    #define SET_REGS()  { ioreg1 = 0; ioreg2 = 0; }
 *  or
 *    #define  SET_REGS()    ioreg1 = 0; ioreg2 = 0;
 *  The last macro would not behave as expected in the if/else construct.
 *  The second to last macro will cause a compiler error in certain uses
 *  of if/else construct
 *
 *  It is not necessary, or recommended, to use this macro where there is
 *  already a valid C statement.  For example, the following is redundant...
 *    #define CALL_FUNC()   st(  func();  )
 *  This should simply be...
 *    #define CALL_FUNC()   func()
 *
 * (The while condition below evaluates false without generating a
 *  constant-controlling-loop type of warning on most compilers.)
 */
#define st(x)      do { x } while (__LINE__ == -1)

/* This macro is used to define asm NOP instruction with
 * different compiler/assembler
 */
#ifdef ccs
#define ASM_NOP    asm(" NOP")
#elif defined rvmdk
#define ASM_NOP   __nop()
#else
#define ASM_NOP    asm("NOP")
#endif

/**************************************************************************************************
 */
#endif