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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 <asm/uaccess.h>
struct poll_table_entry {
struct file * filp;
struct wait_queue wait;
struct wait_queue ** wait_address;
};
typedef struct poll_table_struct {
unsigned int nr;
struct poll_table_entry * entry;
} poll_table;
#define __MAX_POLL_TABLE_ENTRIES (PAGE_SIZE / sizeof (struct poll_table_entry))
extern inline void poll_wait(struct file * filp, struct wait_queue ** wait_address, poll_table *p)
{
struct poll_table_entry * entry;
if (!p || !wait_address)
return;
if (p->nr >= __MAX_POLL_TABLE_ENTRIES)
return;
entry = p->entry + p->nr;
entry->filp = filp;
filp->f_count++;
entry->wait_address = wait_address;
entry->wait.task = current;
entry->wait.next = NULL;
add_wait_queue(wait_address,&entry->wait);
p->nr++;
}
/*
* For the kernel fd_set we use a fixed set-size for allocation purposes.
* This set-size doesn't necessarily bear any relation to the size the user
* uses, but should preferably obviously be larger than any possible user
* size (NR_OPEN bits).
*
* We need 6 bitmaps (in/out/ex for both incoming and outgoing), and we
* allocate one page for all the bitmaps. Thus we have 8*PAGE_SIZE bits,
* to be divided by 6. And we'd better make sure we round to a full
* long-word (in fact, we'll round to 64 bytes).
*/
#define KFDS_64BLOCK ((PAGE_SIZE/(6*64))*64)
#define KFDS_NR (KFDS_64BLOCK*8 > NR_OPEN ? NR_OPEN : KFDS_64BLOCK*8)
typedef unsigned long kernel_fd_set[KFDS_NR/__NFDBITS];
typedef struct {
kernel_fd_set in, out, ex;
kernel_fd_set res_in, res_out, res_ex;
} fd_set_buffer;
/*
* 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)
{
/* round up nr to nearest "unsigned long" */
nr = (nr + 8*sizeof(long) - 1) / (8*sizeof(long)) * sizeof(long);
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) {
nr = (nr + 8*sizeof(long) - 1) / (8*sizeof(long))*sizeof(long);
__copy_to_user(ufdset, fdset, nr);
}
}
static inline
void zero_fd_set(unsigned long nr, unsigned long *fdset)
{
nr = (nr + 8*sizeof(long) - 1) / (8*sizeof(long)) * sizeof(long);
memset(fdset, 0, nr);
}
extern int do_select(int n, fd_set_buffer *fds, long *timeout);
#endif /* KERNEL */
#endif /* _LINUX_POLL_H */
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