xdr.h

unxi下共享内存的使用

/*
 * include/linux/sunrpc/xdr.h
 *
 * Copyright (C) 1995-1997 Olaf Kirch <[e-mail]>
 */

#ifndef _SUNRPC_XDR_H_
#define _SUNRPC_XDR_H_

#ifdef __KERNEL__

#include <linux/uio.h>

/*
 * Buffer adjustment
 */
#define XDR_QUADLEN(l)		(((l) + 3) >> 2)

/*
 * Generic opaque `network object.' At the kernel level, this type
 * is used only by lockd.
 */
#define XDR_MAX_NETOBJ		1024
struct xdr_netobj {
	unsigned int		len;
	u8 *			data;
};

/*
 * This is the generic XDR function. rqstp is either a rpc_rqst (client
 * side) or svc_rqst pointer (server side).
 * Encode functions always assume there's enough room in the buffer.
 */
typedef int	(*kxdrproc_t)(void *rqstp, u32 *data, void *obj);

/*
 * pre-xdr'ed macros.
 */

#define	xdr_zero	__constant_htonl(0)
#define	xdr_one		__constant_htonl(1)
#define	xdr_two		__constant_htonl(2)

#define	rpc_success		__constant_htonl(RPC_SUCCESS)
#define	rpc_prog_unavail	__constant_htonl(RPC_PROG_UNAVAIL)
#define	rpc_prog_mismatch	__constant_htonl(RPC_PROG_MISMATCH)
#define	rpc_proc_unavail	__constant_htonl(RPC_PROC_UNAVAIL)
#define	rpc_garbage_args	__constant_htonl(RPC_GARBAGE_ARGS)
#define	rpc_system_err		__constant_htonl(RPC_SYSTEM_ERR)

#define	rpc_auth_ok		__constant_htonl(RPC_AUTH_OK)
#define	rpc_autherr_badcred	__constant_htonl(RPC_AUTH_BADCRED)
#define	rpc_autherr_rejectedcred __constant_htonl(RPC_AUTH_REJECTEDCRED)
#define	rpc_autherr_badverf	__constant_htonl(RPC_AUTH_BADVERF)
#define	rpc_autherr_rejectedverf __constant_htonl(RPC_AUTH_REJECTEDVERF)
#define	rpc_autherr_tooweak	__constant_htonl(RPC_AUTH_TOOWEAK)


/*
 * Miscellaneous XDR helper functions
 */
u32 *	xdr_encode_array(u32 *p, const char *s, unsigned int len);
u32 *	xdr_encode_string(u32 *p, const char *s);
u32 *	xdr_decode_string(u32 *p, char **sp, int *lenp, int maxlen);
u32 *	xdr_decode_string_inplace(u32 *p, char **sp, int *lenp, int maxlen);
u32 *	xdr_encode_netobj(u32 *p, const struct xdr_netobj *);
u32 *	xdr_decode_netobj(u32 *p, struct xdr_netobj *);
u32 *	xdr_decode_netobj_fixed(u32 *p, void *obj, unsigned int len);

/*
 * Decode 64bit quantities (NFSv3 support)
 */
static inline u32 *
xdr_encode_hyper(u32 *p, __u64 val)
{
	*p++ = htonl(val >> 32);
	*p++ = htonl(val & 0xFFFFFFFF);
	return p;
}

static inline u32 *
xdr_decode_hyper(u32 *p, __u64 *valp)
{
	*valp  = ((__u64) ntohl(*p++)) << 32;
	*valp |= ntohl(*p++);
	return p;
}

/*
 * Adjust iovec to reflect end of xdr'ed data (RPC client XDR)
 */
static inline int
xdr_adjust_iovec(struct iovec *iov, u32 *p)
{
	return iov->iov_len = ((u8 *) p - (u8 *) iov->iov_base);
}

void xdr_shift_iovec(struct iovec *, int, size_t);
void xdr_zero_iovec(struct iovec *, int, size_t);

#endif /* __KERNEL__ */

#endif /* _SUNRPC_XDR_H_ */