mbed-os/mbed-client-libservice/ns_types.h

406 lines
13 KiB
C

/*
* Copyright (c) 2014-2015 ARM Limited. All rights reserved.
* 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.
*/
/*
* ns_types.h - Basic compiler and type setup for Nanostack libraries.
*/
#ifndef NS_TYPES_H_
#define NS_TYPES_H_
/** \file
* \brief Basic compiler and type setup
*
* We currently assume C99 or later.
*
* C99 features being relied on:
*
* - <inttypes.h> and <stdbool.h>
* - inline (with C99 semantics, not C++ as per default GCC);
* - designated initialisers;
* - compound literals;
* - restrict;
* - [static N] in array parameters;
* - declarations in for statements;
* - mixing declarations and statements
*
* Compilers should be set to C99 or later mode when building Nanomesh source.
* For GCC this means "-std=gnu99" (C99 with usual GNU extensions).
*
* Also, a little extra care is required for public header files that could be
* included from C++, especially as C++ lacks some C99 features.
*
* (TODO: as this is exposed to API users, do we need a predefine to distinguish
* internal and external use, for finer control? Not yet, but maybe...)
*/
/* Make sure <stdint.h> defines its macros if C++ */
#ifndef __STDC_LIMIT_MACROS
#define __STDC_LIMIT_MACROS
#endif
#ifndef __STDC_CONSTANT_MACROS
#define __STDC_CONSTANT_MACROS
#endif
#include <stddef.h>
#include <inttypes.h> // includes <stdint.h>; debugf() users need PRIu32 etc
#include <stdbool.h>
/*
* Create the optional <stdint.h> 24-bit types if they don't exist (worth trying
* to use them, as they could exist and be more efficient than 32-bit on 8-bit
* systems...)
*/
#ifndef UINT_LEAST24_MAX
typedef uint_least32_t uint_least24_t;
#define UINT_LEAST24_MAX UINT_LEAST32_MAX
#define UINT24_C(x) UINT32_C(x)
#define PRIoLEAST24 PRIoLEAST32
#define PRIuLEAST24 PRIuLEAST32
#define PRIxLEAST24 PRIxLEAST32
#define PRIXLEAST24 PRIXLEAST32
#endif
#ifndef INT_LEAST24_MAX
typedef int_least32_t int_least24_t;
#define INT_LEAST24_MIN INT_LEAST32_MIN
#define INT_LEAST24_MAX INT_LEAST32_MAX
#define INT24_C(x) INT32_C(x)
#define PRIdLEAST24 PRIdLEAST32
#define PRIiLEAST24 PRIiLEAST32
#endif
#ifndef UINT_FAST24_MAX
typedef uint_fast32_t uint_fast24_t;
#define UINT_FAST24_MAX UINT_FAST32_MAX
#define PRIoFAST24 PRIoFAST32
#define PRIuFAST24 PRIuFAST32
#define PRIxFAST24 PRIxFAST32
#define PRIXFAST24 PRIXFAST32
#endif
#ifndef INT_FAST24_MAX
typedef int_fast32_t int_fast24_t;
#define INT_FAST24_MIN INT_FAST32_MIN
#define INT_FAST24_MAX INT_FAST32_MAX
#define PRIdFAST24 PRIdFAST32
#define PRIiFAST24 PRIiFAST32
#endif
/* Function attribute - C11 "noreturn" or C++11 "[[noreturn]]" */
#ifndef NS_NORETURN
#if defined __cplusplus && __cplusplus >= 201103L
#define NS_NORETURN [[noreturn]]
#elif !defined __cplusplus && __STDC_VERSION__ >= 201112L
#define NS_NORETURN _Noreturn
#elif defined __GNUC__
#define NS_NORETURN __attribute__((__noreturn__))
#elif defined __IAR_SYSTEMS_ICC__
#define NS_NORETURN __noreturn
#else
#define NS_NORETURN
#endif
#endif
/* C11's "alignas" macro, emulated for integer expressions if necessary */
#ifndef __alignas_is_defined
#if defined __TASKING__
#define alignas(n) __align(n)
#define __alignas_is_defined 1
#elif (defined __STDC_VERSION__ && __STDC_VERSION__ >= 201112L) || (defined __cplusplus && __cplusplus >= 201103L)
# if defined __ARMCC_VERSION && __ARMCC_VERSION < 6120000
/* Workaround for Arm Compiler versions prior to 6.12 */
# if !defined __cplusplus
# define alignas _Alignas
# endif
# define __alignas_is_defined 1
# else
# include <stdalign.h>
# endif
#elif defined __GNUC__
#define alignas(n) __attribute__((__aligned__(n)))
#define __alignas_is_defined 1
#elif defined __IAR_SYSTEMS_ICC__
/* Does this really just apply to the next variable? */
#define alignas(n) __Alignas(data_alignment=n)
#define __Alignas(x) _Pragma(#x)
#define __alignas_is_defined 1
#endif
#endif
/**
* Marker for functions or objects that may be unused, suppressing warnings.
* Place after the identifier:
* ~~~
* static int X MAYBE_UNUSED = 3;
* static int foo(void) MAYBE_UNUSED;
* ~~~
*/
#if defined __GNUC__
#define MAYBE_UNUSED __attribute__((unused))
#else
#define MAYBE_UNUSED
#endif
/*
* C++ (even C++11) doesn't provide restrict: define away or provide
* alternative.
*/
#ifdef __cplusplus
#ifdef __GNUC__
#define restrict __restrict
#else
#define restrict
#endif
#endif /* __cplusplus */
/**
* C++ doesn't allow "static" in function parameter types: ie
* ~~~
* entry_t *find_entry(const uint8_t address[static 16])
* ~~~
* If a header file may be included from C++, use this __static define instead.
*
* (Syntax introduced in C99 - `uint8_t address[16]` in a prototype was always
* equivalent to `uint8_t *address`, but the C99 addition of static tells the
* compiler that address is never NULL, and always points to at least 16
* elements. This adds no new type-checking, but the information could aid
* compiler optimisation, and it can serve as documentation).
*/
#ifdef __cplusplus
#define __static
#else
#define __static static
#endif
#ifdef __GNUC__
#define NS_GCC_VERSION (__GNUC__ * 10000 \
+ __GNUC_MINOR__ * 100 \
+ __GNUC_PATCHLEVEL__)
#endif
/** \brief Compile-time assertion
*
* C11 provides _Static_assert, as does GCC even in C99 mode (and
* as a freestanding implementation, we can't rely on <assert.h> to get
* the static_assert macro).
* C++11 provides static_assert as a keyword, as does G++ in C++0x mode.
*
* The assertion acts as a declaration that can be placed at file scope, in a
* code block (except after a label), or as a member of a struct/union. It
* produces a compiler error if "test" evaluates to 0.
*
* Note that this *includes* the required semicolon when defined, else it
* is totally empty, permitting use in structs. (If the user provided the `;`,
* it would leave an illegal stray `;` if unavailable).
*/
#ifdef __cplusplus
# if __cplusplus >= 201103L || __cpp_static_assert >= 200410
# define NS_STATIC_ASSERT(test, str) static_assert(test, str);
# elif defined __GXX_EXPERIMENTAL_CXX0X__ && NS_GCC_VERSION >= 40300
# define NS_STATIC_ASSERT(test, str) __extension__ static_assert(test, str);
# else
# define NS_STATIC_ASSERT(test, str)
# endif
#else /* C */
# if __STDC_VERSION__ >= 201112L
# define NS_STATIC_ASSERT(test, str) _Static_assert(test, str);
# elif defined __GNUC__ && NS_GCC_VERSION >= 40600
# ifdef _Static_assert
/*
* Some versions of glibc cdefs.h (which comes in via <stdint.h> above)
* attempt to define their own _Static_assert (if GCC < 4.6 or
* __STRICT_ANSI__) using an extern declaration, which doesn't work in a
* struct/union.
*
* For GCC >= 4.6 and __STRICT_ANSI__, we can do better - just use
* the built-in _Static_assert with __extension__. We have to do this, as
* ns_list.h needs to use it in a union. No way to get at it though, without
* overriding their define.
*/
# undef _Static_assert
# define _Static_assert(x, y) __extension__ _Static_assert(x, y)
# endif
# define NS_STATIC_ASSERT(test, str) __extension__ _Static_assert(test, str);
# else
# define NS_STATIC_ASSERT(test, str)
#endif
#endif
/** \brief Pragma to suppress warnings about unusual pointer values.
*
* Useful if using "poison" values.
*/
#ifdef __IAR_SYSTEMS_ICC__
#define NS_FUNNY_INTPTR_OK _Pragma("diag_suppress=Pe1053")
#define NS_FUNNY_INTPTR_RESTORE _Pragma("diag_default=Pe1053")
#else
#define NS_FUNNY_INTPTR_OK
#define NS_FUNNY_INTPTR_RESTORE
#endif
/** \brief Pragma to suppress warnings about always true/false comparisons
*/
#if defined __GNUC__ && NS_GCC_VERSION >= 40600
#define NS_FUNNY_COMPARE_OK _Pragma("GCC diagnostic push") \
_Pragma("GCC diagnostic ignored \"-Wtype-limits\"")
#define NS_FUNNY_COMPARE_RESTORE _Pragma("GCC diagnostic pop")
#else
#define NS_FUNNY_COMPARE_OK
#define NS_FUNNY_COMPARE_RESTORE
#endif
/** \brief Pragma to suppress warnings arising from dummy definitions.
*
* Useful when you have function-like macros that returning constants
* in cut-down builds. Can be fairly cavalier about disabling as we
* do not expect every build to use this macro. Generic builds of
* components should ensure this is not included by only using it in
* a ifdef blocks providing dummy definitions.
*/
#if defined __IAR_SYSTEMS_ICC__
// controlling expression is constant
#define NS_DUMMY_DEFINITIONS_OK _Pragma("diag_suppress=Pe236")
#else
#define NS_DUMMY_DEFINITIONS_OK
#endif
/** \brief Convert pointer to member to pointer to containing structure */
#define NS_CONTAINER_OF(ptr, type, member) \
((type *) ((char *) (ptr) - offsetof(type, member)))
/*
* Inlining could cause problems when mixing with C++; provide a mechanism to
* disable it. This could also be turned off for other reasons (although
* this can usually be done through a compiler flag, eg -O0 on gcc).
*/
#ifndef __cplusplus
#define NS_ALLOW_INLINING
#endif
/* There is inlining problem in GCC version 4.1.x and we know it works in 4.6.3 */
#if defined __GNUC__ && NS_GCC_VERSION < 40600
#undef NS_ALLOW_INLINING
#endif
/** \brief Mark a potentially-inlineable function.
*
* We follow C99 semantics, which requires precisely one external definition.
* To also allow inlining to be totally bypassed under control of
* NS_ALLOW_INLINING, code can be structured as per the example of ns_list:
*
* foo.h
* -----
* ~~~
* NS_INLINE int my_func(int);
*
* #if defined NS_ALLOW_INLINING || defined FOO_FN
* #ifndef FOO_FN
* #define FOO_FN NS_INLINE
* #endif
* FOO_FN int my_func(int a)
* {
* definition;
* }
* #endif
* ~~~
* foo.c
* -----
* ~~~
* #define FOO_FN extern
* #include "foo.h"
* ~~~
* Which generates:
* ~~~
* NS_ALLOW_INLINING set NS_ALLOW_INLINING unset
* ===================== =======================
* Include foo.h Include foo.h
* ------------- -------------
* inline int my_func(int); int my_func(int);
*
* // inline definition
* inline int my_func(int a)
* {
* definition;
* }
*
* Compile foo.c Compile foo.c
* ------------- -------------
* (from .h) inline int my_func(int); int my_func(int);
*
* // external definition
* // because of no "inline" // normal external definition
* extern int my_func(int a) extern int my_func(int a)
* { {
* definition; definition;
* } }
* ~~~
*
* Note that even with inline keywords, whether the compiler inlines or not is
* up to it. For example, gcc at "-O0" will not inline at all, and will always
* call the real functions in foo.o, just as if NS_ALLOW_INLINING was unset.
* At "-O2", gcc could potentially inline everything, meaning that foo.o is not
* referenced at all.
*
* Alternatively, you could use "static inline", which gives every caller its
* own internal definition. This is compatible with C++ inlining (which expects
* the linker to eliminate duplicates), but in C it's less efficient if the code
* ends up non-inlined, and it's harder to breakpoint. I don't recommend it
* except for the most trivial functions (which could then probably be macros).
*/
#ifdef NS_ALLOW_INLINING
#define NS_INLINE inline
#else
#define NS_INLINE
#endif
#if defined __SDCC_mcs51 || defined __ICC8051__ || defined __C51__
/* The 8051 environments: SDCC (historic), IAR (current), Keil (future?) */
#define NS_LARGE __xdata
#define NS_LARGE_PTR __xdata
#ifdef __ICC8051__
#define NS_REENTRANT
#define NS_REENTRANT_PREFIX __idata_reentrant
#else
#define NS_REENTRANT __reentrant
#define NS_REENTRANT_PREFIX
#endif
#define NS_NEAR_FUNC __near_func
#else
/* "Normal" systems. Define it all away. */
#define NS_LARGE
#define NS_LARGE_PTR
#define NS_REENTRANT
#define NS_REENTRANT_PREFIX
#define NS_NEAR_FUNC
#endif
/** \brief Scatter-gather descriptor
*
* Slightly optimised for small platforms - we assume we won't need any
* element bigger than 64K.
*/
typedef struct ns_iovec {
void *iov_base;
uint_fast16_t iov_len;
} ns_iovec_t;
#endif /* NS_TYPES_H */