linux/include/pipe_fs_i.H




#ifndef _LINUX_PIPE_FS_I_H
#define _LINUX_PIPE_FS_I_H

struct pipe_inode_info {
struct wait_queue * wait;
char * base;
unsigned int start;
unsigned int len;
unsigned int lock;
unsigned int rd_openers;
unsigned int wr_openers;
unsigned int readers;
unsigned int writers;
};

#define PIPE_WAIT(inode) ((inode).u.pipe_i.wait)
#define PIPE_BASE(inode) ((inode).u.pipe_i.base)
#define PIPE_START(inode) ((inode).u.pipe_i.start)
#define PIPE_LEN(inode) ((inode).u.pipe_i.len)
#define PIPE_RD_OPENERS(inode) ((inode).u.pipe_i.rd_openers)
#define PIPE_WR_OPENERS(inode) ((inode).u.pipe_i.wr_openers)
#define PIPE_READERS(inode) ((inode).u.pipe_i.readers)
#define PIPE_WRITERS(inode) ((inode).u.pipe_i.writers)
#define PIPE_LOCK(inode) ((inode).u.pipe_i.lock)
#define PIPE_SIZE(inode) PIPE_LEN(inode)

#define PIPE_EMPTY(inode) (PIPE_SIZE(inode)==0)
#define PIPE_FULL(inode) (PIPE_SIZE(inode)==PIPE_BUF)
#define PIPE_FREE(inode) (PIPE_BUF - PIPE_LEN(inode))


#define PIPE_END(inode) ((PIPE_START(inode)+PIPE_LEN(inode))&\
(PIPE_BUF-1))
#define PIPE_MAX_RCHUNK(inode) (PIPE_BUF - PIPE_START(inode))
#define PIPE_MAX_WCHUNK(inode) (PIPE_BUF - PIPE_END(inode))

#endif