mbedtls/library/common.h
Joe Subbiani 0a65d531c5 Improve common.h macro documentation
Imrpoved the descriptions of the macros and parameters and
changing the name of the MBEDTLS_PUT_UINT... macro parameters
to be more descriptive

Signed-off-by: Joe Subbiani <joe.subbiani@arm.com>
2021-08-03 14:02:31 +01:00

192 lines
7.4 KiB
C

/**
* \file common.h
*
* \brief Utility macros for internal use in the library
*/
/*
* Copyright The Mbed TLS Contributors
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
*
* 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.
*/
#ifndef MBEDTLS_LIBRARY_COMMON_H
#define MBEDTLS_LIBRARY_COMMON_H
#if defined(MBEDTLS_CONFIG_FILE)
#include MBEDTLS_CONFIG_FILE
#else
#include "mbedtls/config.h"
#endif
/** Helper to define a function as static except when building invasive tests.
*
* If a function is only used inside its own source file and should be
* declared `static` to allow the compiler to optimize for code size,
* but that function has unit tests, define it with
* ```
* MBEDTLS_STATIC_TESTABLE int mbedtls_foo(...) { ... }
* ```
* and declare it in a header in the `library/` directory with
* ```
* #if defined(MBEDTLS_TEST_HOOKS)
* int mbedtls_foo(...);
* #endif
* ```
*/
#if defined(MBEDTLS_TEST_HOOKS)
#define MBEDTLS_STATIC_TESTABLE
#else
#define MBEDTLS_STATIC_TESTABLE static
#endif
/** Allow library to access its structs' private members.
*
* Although structs defined in header files are publicly available,
* their members are private and should not be accessed by the user.
*/
#define MBEDTLS_ALLOW_PRIVATE_ACCESS
/** Byte Reading Macros
*
* Obtain the most significant byte of x using 0xff
* Using MBEDTLS_BYTE_a will shift a*8 bits
* to retrieve the next byte of information
*/
#define MBEDTLS_BYTE_0( x ) ( (uint8_t) ( ( x ) & 0xff ) )
#define MBEDTLS_BYTE_1( x ) ( (uint8_t) ( ( ( x ) >> 8 ) & 0xff ) )
#define MBEDTLS_BYTE_2( x ) ( (uint8_t) ( ( ( x ) >> 16 ) & 0xff ) )
#define MBEDTLS_BYTE_3( x ) ( (uint8_t) ( ( ( x ) >> 24 ) & 0xff ) )
#define MBEDTLS_CHAR_0( x ) ( (unsigned char) ( ( x ) & 0xff ) )
#define MBEDTLS_CHAR_1( x ) ( (unsigned char) ( ( ( x ) >> 8 ) & 0xff ) )
#define MBEDTLS_CHAR_2( x ) ( (unsigned char) ( ( ( x ) >> 16 ) & 0xff ) )
#define MBEDTLS_CHAR_3( x ) ( (unsigned char) ( ( ( x ) >> 24 ) & 0xff ) )
#define MBEDTLS_CHAR_4( x ) ( (unsigned char) ( ( ( x ) >> 32 ) & 0xff ) )
#define MBEDTLS_CHAR_5( x ) ( (unsigned char) ( ( ( x ) >> 40 ) & 0xff ) )
#define MBEDTLS_CHAR_6( x ) ( (unsigned char) ( ( ( x ) >> 48 ) & 0xff ) )
#define MBEDTLS_CHAR_7( x ) ( (unsigned char) ( ( ( x ) >> 56 ) & 0xff ) )
/**
* Get the unsigned 32 bits integer corresponding to four bytes in
* big-endian order (MSB first).
*
* \param data Base address of the memory to get the four bytes from.
* \param offset Offset from \p base of the first and most significant
* byte of the four bytes to build the 32 bits unsigned
* integer from.
*/
#ifndef MBEDTLS_GET_UINT32_BE
#define MBEDTLS_GET_UINT32_BE( data , offset ) \
( \
( (uint32_t) ( data )[( offset ) ] << 24 ) \
| ( (uint32_t) ( data )[( offset ) + 1] << 16 ) \
| ( (uint32_t) ( data )[( offset ) + 2] << 8 ) \
| ( (uint32_t) ( data )[( offset ) + 3] ) \
)
#endif
/**
* Put in memory a 32 bits unsigned integer in big-endian order.
*
* \param n 32 bits unsigned integer to put in memory
* \param data Base address of the memory where to put the 32
* bits unsigned integer in.
* \param offset Offset from \p base where to put the most significant
* byte of the 32 bits unsigned integer \p n.
*/
#ifndef MBEDTLS_PUT_UINT32_BE
#define MBEDTLS_PUT_UINT32_BE( n, data, offset ) \
do { \
( data )[( offset ) ] = (unsigned char) ( (n) >> 24 ); \
( data )[( offset ) + 1] = (unsigned char) ( (n) >> 16 ); \
( data )[( offset ) + 2] = (unsigned char) ( (n) >> 8 ); \
( data )[( offset ) + 3] = (unsigned char) ( (n) ); \
} while( 0 )
#endif
/**
* Get the unsigned 32 bits integer corresponding to four bytes in
* little-endian order (LSB first).
*
* \param data Base address of the memory to get the four bytes from.
* \param offset Offset from \p base of the first and least significant
* byte of the four bytes to build the 32 bits unsigned
* integer from.
*/
#ifndef MBEDTLS_GET_UINT32_LE
#define MBEDTLS_GET_UINT32_LE( data, offset ) \
( \
( (uint32_t) ( data )[( offset ) ] ) \
| ( (uint32_t) ( data )[( offset ) + 1] << 8 ) \
| ( (uint32_t) ( data )[( offset ) + 2] << 16 ) \
| ( (uint32_t) ( data )[( offset ) + 3] << 24 ) \
)
#endif
/**
* Put in memory a 32 bits unsigned integer in little-endian order.
*
* \param n 32 bits unsigned integer to put in memory
* \param data Base address of the memory where to put the 32
* bits unsigned integer in.
* \param offset Offset from \p base where to put the least significant
* byte of the 32 bits unsigned integer \p n.
*/
#ifndef MBEDTLS_PUT_UINT32_LE
#define MBEDTLS_PUT_UINT32_LE( n, data, offset ) \
do { \
( data )[( offset ) ] = (unsigned char) ( ( (n) ) & 0xFF ); \
( data )[( offset ) + 1] = (unsigned char) ( ( (n) >> 8 ) & 0xFF ); \
( data )[( offset ) + 2] = (unsigned char) ( ( (n) >> 16 ) & 0xFF ); \
( data )[( offset ) + 3] = (unsigned char) ( ( (n) >> 24 ) & 0xFF ); \
} while( 0 )
#endif
/**
* Get the unsigned 16 bits integer corresponding to four bytes in
* little-endian order (LSB first).
*
* \param data Base address of the memory to get the four bytes from.
* \param offset Offset from \p base of the first and least significant
* byte of the four bytes to build the 16 bits unsigned
* integer from.
*/
#ifndef MBEDTLS_GET_UINT16_LE
#define MBEDTLS_GET_UINT16_LE( data, offset ) \
( \
( (uint16_t) ( data )[( offset ) ] ) \
| ( (uint16_t) ( data )[( offset ) + 1] << 8 ) \
)
#endif
/**
* Put in memory a 16 bits unsigned integer in little-endian order.
*
* \param n 16 bits unsigned integer to put in memory
* \param data Base address of the memory where to put the 16
* bits unsigned integer in.
* \param offset Offset from \p base where to put the least significant
* byte of the 16 bits unsigned integer \p n.
*/
#ifndef MBEDTLS_PUT_UINT16_LE
#define MBEDTLS_PUT_UINT16_LE( n, data, offset ) \
{ \
( data )[( offset ) ] = (unsigned char) ( ( (n) ) & 0xFF ); \
( data )[( offset ) + 1] = (unsigned char) ( ( (n) >> 8 ) & 0xFF ); \
}
#endif
#endif /* MBEDTLS_LIBRARY_COMMON_H */