zephyr/include/pthread.h

387 lines
8.9 KiB
C

/*
* Copyright (c) 2017 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#ifndef __PTHREAD_H__
#define __PTHREAD_H__
#ifdef CONFIG_NEWLIB_LIBC
#include <time.h>
#else
/* This should probably live somewhere else but Zephyr doesn't
* currently have a stdc layer to provide it
*/
struct timespec {
s32_t tv_sec;
s32_t tv_nsec;
};
#endif
static inline s32_t _ts_to_ms(const struct timespec *to)
{
return (to->tv_sec * 1000) + (to->tv_nsec / 1000000);
}
typedef struct pthread_mutex {
struct k_sem *sem;
} pthread_mutex_t;
typedef struct pthread_mutexattr {
int unused;
} pthread_mutexattr_t;
typedef struct pthread_cond {
_wait_q_t wait_q;
} pthread_cond_t;
typedef struct pthread_condattr {
int unused;
} pthread_condattr_t;
/**
* @brief Declare a pthread condition variable
*
* Declaration API for a pthread condition variable. This is not a
* POSIX API, it's provided to better conform with Zephyr's allocation
* strategies for kernel objects.
*
* @param name Symbol name of the condition variable
*/
#define PTHREAD_COND_DEFINE(name) \
struct pthread_cond name = { \
.wait_q = SYS_DLIST_STATIC_INIT(&name.wait_q), \
}
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*/
static inline int pthread_cond_init(pthread_cond_t *cv,
const pthread_condattr_t *att)
{
ARG_UNUSED(att);
sys_dlist_init(&cv->wait_q);
return 0;
}
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*/
static inline int pthread_cond_destroy(pthread_cond_t *cv)
{
return 0;
}
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*/
int pthread_cond_signal(pthread_cond_t *cv);
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*/
int pthread_cond_broadcast(pthread_cond_t *cv);
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*/
int pthread_cond_wait(pthread_cond_t *cv, pthread_mutex_t *mut);
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*/
int pthread_cond_timedwait(pthread_cond_t *cv, pthread_mutex_t *mut,
const struct timespec *to);
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1.
*
* Note that pthread attribute structs are currently noops in Zephyr.
*/
static inline int pthread_condattr_init(pthread_condattr_t *att)
{
return 0;
}
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*
* Note that pthread attribute structs are currently noops in Zephyr.
*/
static inline int pthread_condattr_destroy(pthread_condattr_t *att)
{
return 0;
}
/**
* @brief Declare a pthread mutex
*
* Declaration API for a pthread mutex. This is not a POSIX API, it's
* provided to better conform with Zephyr's allocation strategies for
* kernel objects.
*
* @param name Symbol name of the mutex
*/
#define PTHREAD_MUTEX_DEFINE(name) \
K_SEM_DEFINE(name##_psem, 1, 1); \
struct pthread_mutex name = { \
.sem = &name##_psem, \
}
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*/
static inline int pthread_mutex_init(pthread_mutex_t *m,
const pthread_mutexattr_t *att)
{
ARG_UNUSED(att);
k_sem_init(m->sem, 1, 1);
return 0;
}
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*/
static inline int pthread_mutex_destroy(pthread_mutex_t *m)
{
ARG_UNUSED(m);
return 0;
}
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*/
static inline int pthread_mutex_lock(pthread_mutex_t *m)
{
return k_sem_take(m->sem, K_FOREVER);
}
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*/
static inline int pthread_mutex_timedlock(pthread_mutex_t *m,
const struct timespec *to)
{
int ret = k_sem_take(m->sem, _ts_to_ms(to));
return ret == -EAGAIN ? -ETIMEDOUT : ret;
}
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*/
int pthread_mutex_trylock(pthread_mutex_t *m);
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*/
static inline int pthread_mutex_unlock(pthread_mutex_t *m)
{
k_sem_give(m->sem);
return 0;
}
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*
* Note that pthread attribute structs are currently noops in Zephyr.
*/
static inline int pthread_mutexattr_init(pthread_mutexattr_t *m)
{
ARG_UNUSED(m);
return 0;
}
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*
* Note that pthread attribute structs are currently noops in Zephyr.
*/
static inline int pthread_mutexattr_destroy(pthread_mutexattr_t *m)
{
ARG_UNUSED(m);
return 0;
}
/* FIXME: these are going to be tricky to implement. Zephyr has (for
* good reason) deprecated its own "initializer" macros in favor of a
* static "declaration" macros instead. Using such a macro inside a
* gcc compound expression to declare and object then reference it
* would work, but gcc limits such expressions to function context
* (because they may need to generate code that runs at assignment
* time) and much real-world use of these initializers is for static
* variables. The best trick I can think of would be to declare it in
* a special section and then initialize that section at runtime
* startup, which sort of defeats the purpose of having these be
* static...
*
* Instead, see the nonstandard PTHREAD_*_DEFINE macros instead, which
* work similarly but conform to Zephyr's paradigms.
*/
/* #define PTHREAD_MUTEX_INITIALIZER */
/* #define PTHREAD_COND_INITIALIZER */
typedef struct pthread_barrier {
_wait_q_t wait_q;
int max;
int count;
} pthread_barrier_t;
typedef struct pthread_barrierattr {
int unused;
} pthread_barrierattr_t;
/**
* @brief Declare a pthread barrier
*
* Declaration API for a pthread barrier. This is not a
* POSIX API, it's provided to better conform with Zephyr's allocation
* strategies for kernel objects.
*
* @param name Symbol name of the barrier
* @param count Thread count, same as the "count" argument to
* pthread_barrier_init()
*/
#define PTHREAD_BARRIER_DEFINE(name, count) \
struct pthread_barrier name = { \
.wait_q = SYS_DLIST_STATIC_INIT(&name.wait_q), \
.max = count, \
}
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*/
int pthread_barrier_wait(pthread_barrier_t *b);
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*/
static inline int pthread_barrier_init(pthread_barrier_t *b,
const pthread_barrierattr_t *attr,
unsigned int count)
{
ARG_UNUSED(attr);
b->max = count;
b->count = 0;
sys_dlist_init(&b->wait_q);
return 0;
}
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*/
static inline int pthread_barrier_destroy(pthread_barrier_t *b)
{
ARG_UNUSED(b);
return 0;
}
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*
* Note that pthread attribute structs are currently noops in Zephyr.
*/
static inline int pthread_barrierattr_init(pthread_barrierattr_t *b)
{
ARG_UNUSED(b);
return 0;
}
/**
* @brief POSIX threading compatibility API
*
* See IEEE 1003.1
*
* Note that pthread attribute structs are currently noops in Zephyr.
*/
static inline int pthread_barrierattr_destroy(pthread_barrierattr_t *b)
{
ARG_UNUSED(b);
return 0;
}
/* Predicates and setters for various pthread attribute values that we
* don't support (or always support: the "process shared" attribute
* can only be true given the way Zephyr implements these
* objects). Leave these undefined for simplicity instead of defining
* stubs to return an error that would have to be logged and
* interpreted just to figure out that we didn't support it in the
* first place. These APIs are very rarely used even in production
* Unix code. Leave the declarations here so they can be easily
* uncommented and implemented as needed.
int pthread_condattr_getclock(const pthread_condattr_t * clockid_t *);
int pthread_condattr_getpshared(const pthread_condattr_t * int *);
int pthread_condattr_setclock(pthread_condattr_t *, clockid_t);
int pthread_condattr_setpshared(pthread_condattr_t *, int);
int pthread_mutex_consistent(pthread_mutex_t *);
int pthread_mutex_getprioceiling(const pthread_mutex_t * int *);
int pthread_mutex_setprioceiling(pthread_mutex_t *, int int *);
int pthread_mutexattr_getprioceiling(const pthread_mutexattr_t *, int *);
int pthread_mutexattr_getprotocol(const pthread_mutexattr_t * int *);
int pthread_mutexattr_getpshared(const pthread_mutexattr_t * int *);
int pthread_mutexattr_getrobust(const pthread_mutexattr_t * int *);
int pthread_mutexattr_gettype(const pthread_mutexattr_t * int *);
int pthread_mutexattr_setprioceiling(pthread_mutexattr_t *, int);
int pthread_mutexattr_setprotocol(pthread_mutexattr_t *, int);
int pthread_mutexattr_setpshared(pthread_mutexattr_t *, int);
int pthread_mutexattr_setrobust(pthread_mutexattr_t *, int);
int pthread_mutexattr_settype(pthread_mutexattr_t *, int);
int pthread_barrierattr_getpshared(const pthread_barrierattr_t *, int *);
int pthread_barrierattr_setpshared(pthread_barrierattr_t *, int);
*/
#endif /* __PTHREAD_H__ */