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#ifndef _SGE_LOCK_FIFO_H_
#define _SGE_LOCK_FIFO_H_
#include <pthread.h>
#include "basis_types.h"
#include "uti/sge_lock.h"
typedef struct sge_fifo_elem_t__ {
/*
* is the waiting thread a reader or writer
*/
bool is_reader;
/*
* has this thread already been signaled
*/
bool is_signaled;
/*
* condition to wakeup a waiting thread
*/
pthread_cond_t cond;
} sge_fifo_elem_t;
typedef struct sge_fifo_rw_lock_t__ {
/*
* mutex to guard this structure
*/
pthread_mutex_t mutex;
/*
* condition to wakeup a waiting thread which got not
* no position in the queue of waiting threads
*/
pthread_cond_t cond;
/*
* fifo array where information about waiting threads is stored.
*/
sge_fifo_elem_t *array;
/*
* position of the next thread which gets the lock
*/
int head;
/*
* position in the array where the next thread will be placed which has to wait
*/
int tail;
/*
* maximum array size
*/
int size;
/*
* number of reader threads currently active
*/
int reader_active;
/*
* number of waiting threads in the queue which try to get a read lock
*/
int reader_waiting;
/*
* number of writer threads currently active (maximum is 1)
*/
int writer_active;
/*
* number of waiting threads in the queue which try to get the write lock
*/
int writer_waiting;
/*
* number of threads which do neither get a lock nor get a free position in the array
*/
int waiting;
/*
* number of waiting threads which have been signaled so that they wake up (maximum is 1)
*/
int signaled;
} sge_fifo_rw_lock_t;
bool
sge_fifo_lock_init(sge_fifo_rw_lock_t *lock);
bool
sge_fifo_lock(sge_fifo_rw_lock_t *lock, bool is_reader);
bool
sge_fifo_ulock(sge_fifo_rw_lock_t *lock, bool is_reader);
void
sge_fifo_debug(sge_locktype_t aType);
void
sge_debug_time(sge_locktype_t aType);
#endif
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