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#ifndef _LINUX_POLL_H
#define _LINUX_POLL_H
#include <asm/poll.h>
#ifdef __KERNEL__
#include <linux/wait.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <asm/uaccess.h>
struct poll_table_entry {
struct file * filp;
wait_queue_t wait;
wait_queue_head_t * wait_address;
};
struct poll_table_page {
struct poll_table_page * next;
unsigned int nr;
struct poll_table_entry * entry;
};
typedef struct poll_table_struct {
int error;
struct poll_table_page * table;
} poll_table;
#define __MAX_POLL_TABLE_ENTRIES ((PAGE_SIZE - sizeof (struct poll_table_page)) / sizeof (struct poll_table_entry))
extern void __pollwait(struct file * filp, wait_queue_head_t * wait_address, poll_table *p);
extern inline void poll_wait(struct file * filp, wait_queue_head_t * wait_address, poll_table *p)
{
if (p && wait_address)
__pollwait(filp, wait_address, p);
}
static inline void poll_initwait(poll_table* pt)
{
pt->error = 0;
pt->table = NULL;
}
extern void poll_freewait(poll_table* pt);
/*
* Scaleable version of the fd_set.
*/
typedef struct {
unsigned long *in, *out, *ex;
unsigned long *res_in, *res_out, *res_ex;
} fd_set_bits;
/*
* How many longwords for "nr" bits?
*/
#define FDS_BITPERLONG (8*sizeof(long))
#define FDS_LONGS(nr) (((nr)+FDS_BITPERLONG-1)/FDS_BITPERLONG)
#define FDS_BYTES(nr) (FDS_LONGS(nr)*sizeof(long))
/*
* We do a VERIFY_WRITE here even though we are only reading this time:
* we'll write to it eventually..
*
* Use "unsigned long" accesses to let user-mode fd_set's be long-aligned.
*/
static inline
int get_fd_set(unsigned long nr, void *ufdset, unsigned long *fdset)
{
nr = FDS_BYTES(nr);
if (ufdset) {
int error;
error = verify_area(VERIFY_WRITE, ufdset, nr);
if (!error && __copy_from_user(fdset, ufdset, nr))
error = -EFAULT;
return error;
}
memset(fdset, 0, nr);
return 0;
}
static inline
void set_fd_set(unsigned long nr, void *ufdset, unsigned long *fdset)
{
if (ufdset)
__copy_to_user(ufdset, fdset, FDS_BYTES(nr));
}
static inline
void zero_fd_set(unsigned long nr, unsigned long *fdset)
{
memset(fdset, 0, FDS_BYTES(nr));
}
extern int do_select(int n, fd_set_bits *fds, long *timeout);
#endif /* KERNEL */
#endif /* _LINUX_POLL_H */
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