#ifndef USR_PTHREAD_H
#define USR_PTHREAD_H

/* Includes */

#include <sys/task.h>
#include <sys/hostabi.h>

/* Macros */

// internal macros
#define _INITIALIZED_RWLOCK ( 1 << 17 )

// pthread-specified macros
#define PTHREAD_CREATE_JOINABLE        0
#define PTHREAD_CREATE_DETACHED        1

#define PTHREAD_PRIO_INHERIT           0 /* TODO */
#define PTHREAD_PRIO_NONE              0 /* TODO */
#define PTHREAD_PRIO_PROTECT           0 /* TODO */

enum {
    PTHREAD_SCOPE_SYSTEM,
#define PTHREAD_SCOPE_SYSTEM           PTHREAD_SCOPE_SYSTEM
    PTHREAD_SCOPE_PROCESS
#define PTHREAD_SCOPE_PROCESS          PTHREAD_SCOPE_PROCESS
};

enum {
    PTHREAD_INHERIT_SCHED,
#define PTHREAD_INHERIT_SCHED          PTHREAD_INHERIT_SCHED
    PTHREAD_EXPLICIT_SCHED
#define PTHREAD_EXPLICIT_SCHED         PTHREAD_EXPLICIT_SCHED
};
  /* Single UNIX Specification v. 2  and later */
#define PTHREAD_MUTEX_NORMAL           0
#define PTHREAD_MUTEX_RECURSIVE        1
#define PTHREAD_MUTEX_ERRORCHECK       2
#define PTHREAD_MUTEX_DEFAULT          PTHREAD_MUTEX_NORMAL

  /* for compatibility (prior to SUS v.2) */
#define PTHREAD_MUTEX_TIMED_NP         PTHREAD_MUTEX_NORMAL
#define PTHREAD_MUTEX_RECURSIVE_NP     PTHREAD_MUTEX_RECURSIVE
#define PTHREAD_MUTEX_ERRORCHECK_NP    PTHREAD_MUTEX_ERRORCHECK
#define PTHREAD_MUTEX_FAST_NP          PTHREAD_MUTEX_NORMAL
#define PTHREAD_MUTEX_ADAPTIVE_NP      PTHREAD_MUTEX_FAST_NP

#define PTHREAD_MUTEX_INITIALIZER      { .__owner = NULL, .__bitflags = 0x1 }

#define PTHREAD_COND_INITIALIZER       { .__mutex = NULL, .__counter = 0 }

#define PTHREAD_ONCE_INIT              { .__mtx = { .__bitflags = 0x3 } }

#define PTHREAD_DESTRUCTOR_ITERATIONS  8

#define PTHREAD_CANCELED               ( (void *) -1 )
#define PTHREAD_CANCEL_ENABLE          0
#define PTHREAD_CANCEL_DISABLE         1
#define PTHREAD_CANCEL_DEFERRED        0
#define PTHREAD_CANCEL_ASYNCHRONOUS    1

#define PTHREAD_PROCESS_PRIVATE        0
#define PTHREAD_PROCESS_SHARED         1

#define PTHREAD_RWLOCK_INITIALIZER     { .__wrowner = 0, .__processShared = 0, .__rlocks = NULL }
#define PTHREAD_RWLOCK_WRITER_NONRECURSIVE_INITIALIZER_NP   PTHREAD_RWLOCK_INITIALIZER

#define PTHREAD_BARRIER_SERIAL_THREAD   _HOST_PTHREAD_BARRIER_SERIAL_THREAD

#if __has_attribute( error ) && __has_attribute( warning )
#define _PTHREAD_UNSUPPORTED  __attribute__(( error("this function is not yet implemented") ))
#define _PTHREAD_NO_EFFECT    __attribute__(( warning("this function currently has no effect") ))
#else
#define _PTHREAD_UNSUPPORTED
#define _PTHREAD_NO_EFFECT
#endif

#define _PTHREAD_NOINLINE     __attribute__(( noinline ))
#if defined( __cplusplus ) && __cplusplus >= 201103L
#define _PTHREAD_NOEXCEPT noexcept
#else
#define _PTHREAD_NOEXCEPT __attribute__((nothrow))
#endif

/* Data types */

typedef int pthread_attr_t;

/* Thread in DiOS is defined as a task.
 * All its data and metadata are stored in task local storage.
 *
 * For `pthread_t` the `__dios_tls` holds in `__data` attribute
 * the _PthreadTLS data.
 *
 * Thread metadata are stored in form of _PThread in the _PthreadTLS.
 * */

#if _HOST_pthread_t_size == 4
typedef uint32_t pthread_t;
#elif _HOST_pthread_t_size == 8
typedef uint64_t pthread_t;
#else
#error Host pthread_t is neither 4 nor 8 bytes.
#endif

struct _PThread;

/* Each mutex tracks its owner to detect if another thread wants to unlock it.
 *
 * Attribute __once is used to detect a single execution of a thread
 * subroutine (see pthread_once implementation).
 *
 * Attribute __type stores type of mutex{PTHREAD_MUTEX_INITIALIZER,
 * PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP, PTHREAD_ERRORCHECK_MUTEX_INITIALIZER_NP}
 *
 * Attribute __lockCounter maintains number of thread owners of this mutex {0,1}.
 * */
typedef union
{
    struct
    {
        __dios_task __owner;

        union
        {
            struct
            {
                unsigned short __once:1;
                unsigned short __type:2;
                unsigned int __lockCounter:28; // change _mutex_adjust_count if bitfield size changes
            };

            int32_t __bitflags;
        };
    };

    uint8_t __padding[ _HOST_pthread_mutex_t_size ];
} pthread_mutex_t;

typedef struct {
    unsigned __type; // just 2 bits needed
} pthread_mutexattr_t;

typedef pthread_mutex_t pthread_spinlock_t;

typedef struct {
    pthread_mutex_t *__mutex; // waits on mutex
    unsigned short __counter;
} pthread_cond_t;

typedef int pthread_condattr_t;
typedef struct { pthread_mutex_t __mtx; } pthread_once_t;

typedef int pthread_key_t;

typedef struct _ReadLock {
    struct _PThread *__owner;
    int __count;
    struct _ReadLock *__next;
} _ReadLock;

typedef struct {
    struct _PThread *__wrowner;
    _ReadLock* __rlocks;
    // not bitfield, struct is padded anyway
    char __processShared;
} pthread_rwlock_t;
typedef int pthread_rwlockattr_t;

typedef struct {
    unsigned short __counter;
    unsigned short __nthreads;
} pthread_barrier_t;

typedef int pthread_barrierattr_t;

#include <sched.h> /* sched_param */
#include <sys/types.h> /* pid_t */

/* Function prototypes */

__BEGIN_DECLS

/* Implementation prototypes */
void __pthread_initialize() _PTHREAD_NOEXCEPT;
void __pthread_finalize() _PTHREAD_NOEXCEPT;

int __register_atfork( void( *prepare )( void ), void ( parent )( void ),
                       void( *child )( void ), void * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_atfork( void (*)(void), void (*)(void), void(*)(void) ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;

int pthread_create( pthread_t *, const pthread_attr_t *, void *(*)(void *), void * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
_PDCLIB_noreturn void pthread_exit( void * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_join( pthread_t, void ** ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_detach( pthread_t thread ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_yield(void) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;

int pthread_attr_destroy( pthread_attr_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_attr_init( pthread_attr_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_attr_getdetachstate( const pthread_attr_t *, int * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_attr_getguardsize( const pthread_attr_t *, size_t *) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_attr_getinheritsched( const pthread_attr_t *, int * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_attr_getschedparam( const pthread_attr_t *, struct sched_param * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_attr_getschedpolicy( const pthread_attr_t *, int * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_attr_getscope( const pthread_attr_t *, int * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_attr_getstack( const pthread_attr_t *, void **, size_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_attr_getstackaddr( const pthread_attr_t *, void ** ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_attr_getstacksize( const pthread_attr_t *, size_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_attr_setdetachstate( pthread_attr_t *, int ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_attr_setguardsize( pthread_attr_t *, size_t ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_attr_setinheritsched( pthread_attr_t *, int ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_attr_setschedparam( pthread_attr_t *, const struct sched_param * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_attr_setschedpolicy( pthread_attr_t *, int ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_attr_setscope( pthread_attr_t *, int ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_attr_setstack( pthread_attr_t *, void *, size_t ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_attr_setstackaddr( pthread_attr_t *, void * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_attr_setstacksize( pthread_attr_t *, size_t ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_NO_EFFECT;

int pthread_getconcurrency( void ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_getcpuclockid( pthread_t, clockid_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_getschedparam( pthread_t, int *, struct sched_param * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_setconcurrency( int ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_setschedparam( pthread_t, int, const struct sched_param * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_setschedprio( pthread_t, int ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;

pthread_t pthread_self( void ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_equal( pthread_t, pthread_t ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;

int pthread_mutex_destroy( pthread_mutex_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_mutex_init( pthread_mutex_t *, const pthread_mutexattr_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_mutex_lock( pthread_mutex_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_mutex_trylock( pthread_mutex_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_mutex_unlock( pthread_mutex_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_mutex_getprioceiling( const pthread_mutex_t *, int * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_mutex_setprioceiling( pthread_mutex_t *, int, int * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_mutex_timedlock( pthread_mutex_t *, const struct timespec * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;

int pthread_mutexattr_destroy( pthread_mutexattr_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_mutexattr_init( pthread_mutexattr_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_mutexattr_gettype( const pthread_mutexattr_t *, int * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_mutexattr_getprioceiling( const pthread_mutexattr_t *, int * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_mutexattr_getprotocol( const pthread_mutexattr_t *, int * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_mutexattr_getpshared( const pthread_mutexattr_t *, int * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_mutexattr_settype( pthread_mutexattr_t *, int ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_mutexattr_setprioceiling( pthread_mutexattr_t *, int ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_mutexattr_setprotocol( pthread_mutexattr_t *, int ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_mutexattr_setpshared( pthread_mutexattr_t *, int ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;

int pthread_spin_destroy( pthread_spinlock_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_spin_init( pthread_spinlock_t *, int ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_spin_lock( pthread_spinlock_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_spin_trylock( pthread_spinlock_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_spin_unlock( pthread_spinlock_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;

int pthread_key_create( pthread_key_t *, void (*)(void *) ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_key_delete( pthread_key_t ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_setspecific( pthread_key_t, const void * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
void *pthread_getspecific( pthread_key_t ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;

int pthread_cond_destroy( pthread_cond_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_cond_init( pthread_cond_t *, const pthread_condattr_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_cond_signal( pthread_cond_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_cond_broadcast( pthread_cond_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_cond_wait( pthread_cond_t *, pthread_mutex_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_cond_timedwait( pthread_cond_t *, pthread_mutex_t *, const struct timespec * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;

int pthread_condattr_destroy( pthread_condattr_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_NO_EFFECT;
int pthread_condattr_getclock( const pthread_condattr_t *, clockid_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_condattr_getpshared( const pthread_condattr_t *, int * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_condattr_init( pthread_condattr_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_NO_EFFECT;
int pthread_condattr_setclock( pthread_condattr_t *, clockid_t ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_condattr_setpshared( pthread_condattr_t *, int ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;

int pthread_once( pthread_once_t *, void (*)(void) ) _PTHREAD_NOINLINE;

int pthread_setcancelstate( int, int * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_setcanceltype( int, int * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_NO_EFFECT;
int pthread_cancel( pthread_t ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_NO_EFFECT;
void pthread_testcancel( void ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
void pthread_cleanup_push( void (*)(void *), void * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
void pthread_cleanup_pop( int ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;

int pthread_rwlock_destroy( pthread_rwlock_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_rwlock_init( pthread_rwlock_t *, const pthread_rwlockattr_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_rwlock_rdlock( pthread_rwlock_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_rwlock_wrlock( pthread_rwlock_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_rwlock_tryrdlock( pthread_rwlock_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_rwlock_trywrlock( pthread_rwlock_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_rwlock_unlock( pthread_rwlock_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;

int pthread_rwlockattr_destroy( pthread_rwlockattr_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_rwlockattr_getpshared( const pthread_rwlockattr_t *, int * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_NO_EFFECT;
int pthread_rwlockattr_init( pthread_rwlockattr_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_rwlockattr_setpshared( pthread_rwlockattr_t *, int ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_NO_EFFECT;

int pthread_barrier_destroy( pthread_barrier_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_barrier_init( pthread_barrier_t *, const pthread_barrierattr_t *, unsigned ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;
int pthread_barrier_wait( pthread_barrier_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE;

int pthread_barrierattr_destroy( pthread_barrierattr_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_barrierattr_getpshared( const pthread_barrierattr_t *, int * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_barrierattr_init( pthread_barrierattr_t * ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;
int pthread_barrierattr_setpshared( pthread_barrierattr_t *, int ) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_UNSUPPORTED;

int sched_get_priority_max(int) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_NO_EFFECT;
int sched_get_priority_min(int) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_NO_EFFECT;
int sched_getparam(pid_t, struct sched_param *) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_NO_EFFECT;
int sched_getscheduler(pid_t) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_NO_EFFECT;
int sched_rr_get_interval(pid_t, struct timespec *) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_NO_EFFECT;
int sched_setparam(pid_t, const struct sched_param *) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_NO_EFFECT;
int sched_setscheduler(pid_t, int, const struct sched_param *) _PTHREAD_NOEXCEPT _PTHREAD_NOINLINE _PTHREAD_NO_EFFECT;

__END_DECLS

#endif