/**
  ******************************************************************************
  * @file    macros.h
  * @author  MCD Application Team
  * @version V3.0.0
  * @date    05-June-2015
  * @brief   Support Macros for functions of the Cryptolib 
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; COPYRIGHT 2015 STMicroelectronics</center></h2>
  *
  * Licensed under MCD-ST Image SW License Agreement V2, (the "License");
  * You may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
  *
  *        http://www.st.com/software_license_agreement_liberty_v2
  *
  * Unless required by applicable law or agreed to in writing, software 
  * distributed under the License is distributed on an "AS IS" BASIS, 
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  *
  ******************************************************************************
  */

/* Define to prevent recursive inclusion -------------------------------------*/
#ifndef __CRL_MACROS_H__
#define __CRL_MACROS_H__

#ifdef __cplusplus
 extern "C" {
#endif

/* Includes ------------------------------------------------------------------*/
/* Exported types --------------------------------------------------------*/  
/* Exported constants --------------------------------------------------------*/  
/* Exported macro ------------------------------------------------------------*/
/** @addtogroup InternalAPI Internal functions
  * @{
  */

/** @addtogroup Macros Macros
  * @{
  */
  
/**
  * @brief  This macro returns the number of 32-bit words required
  *                    to store a variable whose byte size is passed in input
  * @param  b Number of bytes
  * @retval Number of words required to store a variable of size b
  */
#define WORD_COUNT(b) ((int32_t) ((uint32_t) b + 3u) / 4u)

/**
  * @brief  This macro returns the maximum value between two inputs,
  *                    the evaluation is done with the ">" operator
  * @param  a  First input
  * @param  b  Second input  
  * @retval Max(a,b)
  */
#define MAX(a,b)        ((((uint32_t)(a)) > ((uint32_t)(b)))  ? (a)  : (b))

/**
  * @brief  This macro returns the minumum value between two inputs,
  *                     the evaluation is done with the ">" operator
  * @param  a  First input
  * @param  b  Second input  
  * @retval Min(a,b)
  */
#define MIN(a,b)        ((((uint32_t)(a)) > ((uint32_t)(b)))  ? (b)  : (a))


/**
  * @brief  This macro is used to rotate left a 32bit variable by bits bits
  * @param  value The 32 bit value to rotate left
  * @param  bits  The number of bits to rotate left
  * @retval Roteted 32 bit value
  */
#ifdef CL_ON_STM32
#define ROL(value, bits) (uint32_t) __ROR((value),32 - (bits))
#else
#define ROL(value, bits) (uint32_t) (((value) << (bits)) | ((value) >> (32 - (bits))))
#endif

/**
  * @brief  This macro is used to rotate right a 32bit variable by bits bits
  * @param  value The 32 bit value to rotate right
  * @param  bits  The number of bits to rotate right
  * @retval Roteted 32 bit value
  */
#ifdef CL_ON_STM32
#define ROR(value, bits) (uint32_t) __ROR((value),(bits))
#else
#define ROR(value, bits) (uint32_t) (((value) >> (bits)) | ((value) << (32 - (bits))))
#endif

/**
  * @brief  This macro returns the least significant byte from an int32_t
  * @param  P_word The 32-bit from which the least significant byte is taken
  * @retval Least significant byte of P_word
  */
#define BYTE_3(P_word) (uint8_t) (P_word & 0xFFu)

/**
  * @brief  This macro returns the second least significant byte from an int32_t
  * @param  P_word The 32-bit from which the second least significant byte is taken
  * @retval Second least significant byte of P_word
  */
#define BYTE_2(P_word) (uint8_t) ((P_word >> 8) & 0xFFu)

/**
  * @brief  This macro returns the second most significant byte from an int32_t
  * @param  P_word The 32-bit from which the second most significant byte is taken
  * @retval Second most significant byte of P_word
  */
#define BYTE_1(P_word) (uint8_t) ((P_word >> 16) & 0xFFu)

/**
  * @brief  This macro returns the most significant byte from an int32_t
  * @param  P_word The 32-bit from which the most significant byte is taken
  * @retval Most significant byte of x
  */
#define BYTE_0(P_word) (uint8_t) ((P_word >> 24) & 0xFFu)

/**
  * @brief  This macro returns a byte within an word
  * @param   P_word The 32-bit from which the byte
  * @param   P_n The index of the byte to be taken, 0 = MSB, 3 = LSB   
  * @retval  Selected P_n byte from P_word
  */
#define BYTE_X(P_word, P_n) (uint8_t) ((P_word >> (24 - (8 * (P_n)))) & 0xFFu)


/**
  * @brief   This macro outputs the 4 octects that form the input 32bit integer
  * @param   [in]    P_x The input 32bit integer
  * @param   [out]   P_a The least significant byte of P_x   
  * @param   [out]   P_b The second least significant byte of P_x
  * @param   [out]   P_c The second most significant byte of P_x
  * @param   P_d The most significant byte of P_x       
  * @retval  none
  */
#define WORD32_TO_WORD8(P_x,P_a,P_b,P_c,P_d) P_a=(uint8_t)BYTE_3(P_x),P_b=(uint8_t)BYTE_2(P_x),P_c=(uint8_t)BYTE_1(P_x),P_d=(uint8_t)BYTE_0(P_x)


/**
  * @brief   This macro returns an integer from 4 octects
  * @param   P_b0 The most significant byte of the resulting integer
  * @param   P_b1 The second most byte of the resulting integer   
  * @param   P_b2 The second least byte of the resulting integer
  * @param   P_b3 The least byte of the resulting integer       
  * @retval  The resulting 32bit integer formed by P_b0 || P_b1 || P_b2 || P_b3
  */
#define WORD8_TO_WORD32(P_b0, P_b1, P_b2, P_b3) (uint32_t) ((uint32_t)(P_b0) << 24 | (uint32_t)(P_b1) << 16 | (uint32_t)(P_b2) << 8 | (P_b3))

#if CRL_ENDIANNESS==1

/**
  * @brief   This macro is used on little endian cpus to convert a
  *                        4 byte array into a 32 bit integer or viceversa.
  * @param   VariableToConvert The 32 bits value to be converted      
  * @retval  The converted 32 bits value
  */
#ifdef CL_ON_STM32
#define LE_CONVERT_W32(VariableToConvert) (uint32_t) (__REV(VariableToConvert))
#else
#define LE_CONVERT_W32(VariableToConvert) (uint32_t) ((ROL( (uint32_t) VariableToConvert,24) & 0xFF00FF00u ) | (ROL( (uint32_t) VariableToConvert,8) & 0x00FF00FFu ))
#endif

#elif CRL_ENDIANNESS==2

/**
  * @brief   This macro doesn't do anything. It exist for compatibility with
  *                        little endian cpus.
  * @param   VariableToConvert The 32 bit value to be converted      
  * @retval  VariableToConvert as it was passed
  * @note This macro simply returns its argument as it is.  
  */
#define LE_CONVERT_W32(VariableToConvert) (VariableToConvert)
#else  /* CRL_ENDIANNESS NOT SET */
#error "Please select endianness in config.h"
#endif /* #if CRL_ENDIANNESS */


/* Support macro for rand.c for big endian cpus */
#if CRL_ENDIANNESS==2

/**
  * @brief   This macro is used on big endian cpus to convert a
  *                        a 32 bit integer into a little endian array of 4 bytes.
  * @param   VariableToConvert The 32 bits value to be converted      
  * @retval  The converted 32 bits value  
  */
#define BE_CONVERT_W32(VariableToConvert) ((ROL(VariableToConvert,24)&0xFF00FF00) | (ROL(VariableToConvert,8)&0x00FF00FF))
#endif

#ifdef CRL_CPU_SUPPORT_MISALIGNED

/**
  * @brief   This macro is used to read a 4 bytes from a byte array and return
  *                        it as a 32-bit word, taking care of system endianness
  * @param   P_pInputBuffer Pointer to the input byte buffer
  * @param   P_index        Index of P_pInputBuffer where the reading should start         
  * @retval  The 32 bits value
  * @note    This macro is for systems where unaligned reading is allowed    
  */
#define BUFFER_2_W32(P_pInputBuffer,P_index)   (LE_CONVERT_W32(*((const uint32_t *) ((P_pInputBuffer)+(P_index)))))
/**
* @brief   This macro is used to read a 4 bytes from a byte array and return
*                        it as a 32-bit word with reversed endiannes
* @param   P_pInputBuffer Pointer to the input byte buffer
* @param   P_index        Index of P_pInputBuffer where the reading should start
* @retval  The 32 bits value
* @note    This macro is for systems where unaligned reading is allowed
*/
#define BUFFER_2_LEW32(P_pInputBuffer,P_index)   ((*((const uint32_t *) ((P_pInputBuffer)+(P_index)))))

/**
  * @brief   This macro is used to write a 32bit integer into a byte buffer,
  *                        taking care of system endianness
  * @param   [out]   P_pOutputBuffer Pointer to the output byte buffer
  * @param   [in]    P_index         Index of P_pOutputBuffer where the writing should start
  * @param   [in]    P_word          The 32-bit word that will be written           
  * @retval  none
  * @note    This macro is for systems where unaligned writing is allowed    
  */
  
#define W32_2_BUFFER(P_pOutputBuffer,P_index,P_word) *((uint32_t*)(P_pOutputBuffer+(P_index)))=LE_CONVERT_W32(P_word)
/**
* @brief   This macro is used to write a 32bit integer into a byte buffer,
*                        with reversed endiannes
* @param   [out]   P_pOutputBuffer Pointer to the output byte buffer
* @param   [in]    P_index         Index of P_pOutputBuffer where the writing should start
* @param   [in]    P_word          The 32-bit word that will be written           
* @retval  none
* @note    This macro is for systems where unaligned writing is allowed    
*/
#define LEW32_2_BUFFER(P_pOutputBuffer,P_index,P_word) *((uint32_t*)(P_pOutputBuffer+(P_index)))=(P_word)
#else

/**
  * @brief   This macro is used to read a 4 bytes from a byte array and return
  *                        it as a 32-bit word
  * @param   P_pInputBuffer Pointer to the input byte buffer
  * @param   P_index        Index of P_pInputBuffer where the reading should start           
  * @retval  The 32 bits value
  * @note    This macro is for systems where unaligned reading is \b not allowed    
  */
#define BUFFER_2_W32(P_pInputBuffer,P_index)   (WORD8_TO_WORD32(P_pInputBuffer[(P_index)],P_pInputBuffer[(P_index)+1],P_pInputBuffer[(P_index)+2],P_pInputBuffer[(P_index)+3]))

/**
* @brief   This macro is used to read a 4 bytes from a byte array and return
*                        it as a 32-bit word with reversed endiannes
* @param   P_pInputBuffer Pointer to the input byte buffer
* @param   P_index        Index of P_pInputBuffer where the reading should start
* @retval  The 32 bits value
* @note    This macro is for systems where unaligned reading is \b not allowed
*/
#define BUFFER_2_LEW32(P_pInputBuffer,P_index)   (WORD8_TO_WORD32((P_pInputBuffer)[(P_index)+3],(P_pInputBuffer)[(P_index)+2],(P_pInputBuffer)[(P_index)+1],(P_pInputBuffer)[(P_index)]))

/**
  * @brief   This macro is used to write a 32bit integer into a byte buffer,
  *                        taking care of system endianness
  * @param   [out]   P_pOutputBuffer Pointer to the output byte buffer
  * @param   [in]    P_index         Index of P_pOutputBuffer where the writing should start
  * @param   [in]    P_word          The 32-bit word that will be written             
  * @retval  none
  * @note    This macro is for systems where unaligned writing is \b  not allowed    
  */
#define W32_2_BUFFER(P_pOutputBuffer,P_index,P_word) WORD32_TO_WORD8((P_word),P_pOutputBuffer[(P_index)+3],P_pOutputBuffer[(P_index)+2],P_pOutputBuffer[(P_index)+1],P_pOutputBuffer[(P_index)])

/**
* @brief   This macro is used to write a 32bit integer into a byte buffer,
*                        with reversed endiannes
* @param   [out]   P_pOutputBuffer Pointer to the output byte buffer
* @param   [in]    P_index         Index of P_pOutputBuffer where the writing should start
* @param   [in]    P_word          The 32-bit word that will be written
* @retval  none
* @note    This macro is for systems where unaligned writing is \b  not allowed
*/
#define LEW32_2_BUFFER(P_pOutputBuffer,P_index,P_word) WORD32_TO_WORD8((P_word),(P_pOutputBuffer)[(P_index)],(P_pOutputBuffer)[(P_index)+1],(P_pOutputBuffer)[(P_index)+2],(P_pOutputBuffer)[(P_index)+3])
   

#endif

/**
  * @}
  */

/**
  * @}
  */
  
#ifdef __cplusplus
}
#endif
/* Exported functions ------------------------------------------------------- */

#endif /*__CRL_MACROS_H__*/

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/