#ifndef SPINLOCKS_H
#define SPINLOCKS_H

#define NR_CPUS 4
#define NR_RESOURCES sizeof(resource_mask_t)*8

extern int events;

typedef enum {read_req, write_req} request_type;
typedef enum {waiting, acquired, entitled} request_status;
typedef unsigned long resource_mask_t;

typedef struct request_struct {
    resource_mask_t resources;
    request_status status;
    request_type type;
} request;

typedef struct spinlock_struct {
    unsigned int serving;
    unsigned int next_ticket;
} spinlock_t;

typedef struct rwrnlp_struct {
    resource_mask_t unavailable;
    resource_mask_t wentitled;
    resource_mask_t wlocked;

    int enter[NR_CPUS];
    int leave[NR_CPUS];
    request requests[NR_CPUS][2];
    int curr[NR_CPUS];

    request* wqueue[NR_RESOURCES][NR_CPUS];
    unsigned int whead[NR_RESOURCES];
    unsigned int wtail[NR_RESOURCES];

    spinlock_t *enqueue;
    spinlock_t *state;

} rwrnlp;

void spin_init(spinlock_t *lock);

void spin_lock(spinlock_t *lock);

void spin_unlock(spinlock_t *lock);

void rwrnlp_init(rwrnlp *lock);

long rwrnlp_read_lock(rwrnlp *lock, resource_mask_t resources, int processor);

long rwrnlp_write_lock(rwrnlp *lock, resource_mask_t resources, int processor);

long rwrnlp_read_unlock(rwrnlp *lock, int processor);

long rwrnlp_write_unlock(rwrnlp *lock, int processor);

#endif //SPINLOCKS_H