git: 9front

ref: 3ad7388b7424d20f343d12b4f2282fc6d3938e9e
dir: /sys/include/ape/qlock.h/

#ifndef _PLAN9_SOURCE
  This header file is an extension to ANSI/POSIX
#endif

#ifndef __QLOCK_H_
#define __QLOCK_H_
#pragma lib "/$M/lib/ape/lib9.a"

#include <u.h>
#include <lock.h>

typedef struct QLp QLp;
struct QLp
{
	int	inuse;
	int	state;
	QLp	*next;
};

typedef
struct QLock
{
	Lock	lock;
	int	locked;
	QLp	*head;
	QLp 	*tail;
} QLock;

typedef
struct RWLock
{
	Lock	lock;
	int	readers;	/* number of readers */
	int	writer;		/* number of writers */
	QLp	*head;		/* list of waiting processes */
	QLp	*tail;
} RWLock;

#ifdef __cplusplus
extern "C" {
#endif

extern	void	qlock(QLock*);
extern	void	qunlock(QLock*);
extern	int	canqlock(QLock*);

extern	void	rlock(RWLock*);
extern	void	runlock(RWLock*);
extern	int	canrlock(RWLock*);
extern	void	wlock(RWLock*);
extern	void	wunlock(RWLock*);
extern	int	canwlock(RWLock*);

#ifdef __cplusplus
}
#endif

#endif