Quelle  pg_pthread.h

/*-------------------------------------------------------------------------
 *
 * Declarations for missing POSIX thread components.
 *
 *   Currently this supplies an implementation of pthread_barrier_t for the
 *   benefit of macOS, which lacks it.  These declarations are not in port.h,
 *   because that'd require <pthread.h> to be included by every translation
 *   unit.
 *
 *-------------------------------------------------------------------------
 */

#ifndef PG_PTHREAD_H
#define PG_PTHREAD_H

#include <pthread.h>   /* IWYU pragma: export */

#ifndef HAVE_PTHREAD_BARRIER_WAIT

#ifndef PTHREAD_BARRIER_SERIAL_THREAD
#define PTHREAD_BARRIER_SERIAL_THREAD (-1)
#endif

typedef struct pg_pthread_barrier
{
 bool  sense;   /* we only need a one bit phase */
 int   count;   /* number of threads expected */
 int   arrived;  /* number of threads that have arrived */
 pthread_mutex_t mutex;
 pthread_cond_t cond;
} pthread_barrier_t;

extern int pthread_barrier_init(pthread_barrier_t *barrier,
         const void *attr,
         int count);
extern int pthread_barrier_wait(pthread_barrier_t *barrier);
extern int pthread_barrier_destroy(pthread_barrier_t *barrier);

#endif

#endif