ardupilot/libraries/AP_Common/AP_Common.h

168 lines
5.7 KiB
C++

/*
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT 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
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
///
/// @file AP_Common.h
/// @brief Common definitions and utility routines for the ArduPilot
/// libraries.
///
#pragma once
#include <stdint.h>
#include <stdlib.h>
#include <type_traits>
// used to pack structures
#define PACKED __attribute__((__packed__))
// used to weaken symbols
#define WEAK __attribute__((__weak__))
// used to mark a function that may be unused in some builds
#define UNUSED_FUNCTION __attribute__((unused))
// this can be used to optimize individual functions
#define OPTIMIZE(level) __attribute__((optimize(level)))
// sometimes we need to prevent inlining to prevent large stack usage
#define NOINLINE __attribute__((noinline))
// used to ignore results for functions marked as warn unused
#define IGNORE_RETURN(x) do {if (x) {}} while(0)
#define FMT_PRINTF(a,b) __attribute__((format(printf, a, b)))
#define FMT_SCANF(a,b) __attribute__((format(scanf, a, b)))
// used to forbid copy of objects
#define CLASS_NO_COPY(c) c(const c &other) = delete; c &operator=(const c&) = delete
#ifdef __has_cpp_attribute
# if __has_cpp_attribute(fallthrough)
# define FALLTHROUGH [[fallthrough]]
# elif __has_cpp_attribute(gnu::fallthrough)
# define FALLTHROUGH [[gnu::fallthrough]]
# endif
#endif
#ifndef FALLTHROUGH
# define FALLTHROUGH
#endif
#ifdef __GNUC__
#define WARN_IF_UNUSED __attribute__ ((warn_unused_result))
#else
#define WARN_IF_UNUSED
#endif
#define NORETURN __attribute__ ((noreturn))
#define ToRad(x) radians(x) // *pi/180
#define ToDeg(x) degrees(x) // *180/pi
/* Declare and implement const and non-const versions of the array subscript
* operator. The object is treated as an array of type_ values. */
#define DEFINE_BYTE_ARRAY_METHODS \
inline uint8_t &operator[](size_t i) { return reinterpret_cast<uint8_t *>(this)[i]; } \
inline uint8_t operator[](size_t i) const { return reinterpret_cast<const uint8_t *>(this)[i]; }
/*
check if bit bitnumber is set in value, returned as a
bool. Bitnumber starts at 0 for the first bit
*/
#define BIT_IS_SET(value, bitnumber) (((value) & (1U<<(bitnumber))) != 0)
// get high or low bytes from 2 byte integer
#define LOWBYTE(i) ((uint8_t)(i))
#define HIGHBYTE(i) ((uint8_t)(((uint16_t)(i))>>8))
#define ARRAY_SIZE(_arr) (sizeof(_arr) / sizeof(_arr[0]))
#define UINT16_VALUE(hbyte, lbyte) (static_cast<uint16_t>(((hbyte)<<8)|(lbyte)))
#define UINT32_VALUE(b3, b2, b1, b0) (static_cast<uint32_t>(((b3)<<23)|((b2)<<16)|((b1)<<8)|(b0)))
/*
* See UNUSED_RESULT. The difference is that it receives @uniq_ as the name to
* be used for its internal variable.
*
* @uniq_: a unique name to use for variable name
* @expr_: the expression to be evaluated
*/
#define _UNUSED_RESULT(uniq_, expr_) \
do { \
decltype(expr_) uniq_ __attribute__((unused)); \
uniq_ = expr_; \
} while (0)
/*
* Allow to call a function annotated with warn_unused_result attribute
* without getting a warning, because sometimes this is what we want to do.
*
* @expr_: the expression to be evaluated
*/
#define UNUSED_RESULT(expr_) _UNUSED_RESULT(__unique_name_##__COUNTER__, expr_)
// @}
// assert_storage_size template: assert that the memory used to store an
// item is of a specific size.
// example invocation:
// assert_storage_size<class Location, 16> _assert_storage_size_Location;
// templates are used for this because the compiler's output will
// usually contain details of the template instantiation so you can
// see how the actual size differs from the expected size.
template<typename s, size_t s_size, size_t t> struct _assert_storage_size {
static_assert(s_size == t, "wrong size");
};
template<typename s, size_t t> struct assert_storage_size {
_assert_storage_size<s, sizeof(s), t> _member;
};
////////////////////////////////////////////////////////////////////////////////
/// @name Conversions
///
/// Conversion macros and factors.
///
//@{
/*
Return true if value is between lower and upper bound inclusive.
False otherwise.
*/
bool is_bounded_int32(int32_t value, int32_t lower_bound, int32_t upper_bound);
bool hex_to_uint8(uint8_t a, uint8_t &res); // return the uint8 value of an ascii hex character
/*
strncpy without the warning for not leaving room for nul termination
*/
void strncpy_noterm(char *dest, const char *src, size_t n);
// return the numeric value of an ascii hex character
int16_t char_to_hex(char a);
/*
Bit manipulation
*/
//#define BIT_SET(value, bitnumber) ((value) |= (((typeof(value))1U) << (bitnumber)))
template <typename T> void BIT_SET (T& value, uint8_t bitnumber) noexcept {
static_assert(std::is_integral<T>::value, "Integral required.");
((value) |= ((T)(1U) << (bitnumber)));
}
//#define BIT_CLEAR(value, bitnumber) ((value) &= ~(((typeof(value))1U) << (bitnumber)))
template <typename T> void BIT_CLEAR (T& value, uint8_t bitnumber) noexcept {
static_assert(std::is_integral<T>::value, "Integral required.");
((value) &= ~((T)(1U) << (bitnumber)));
}