Macro's and functions for manipulation of large file descriptor sets. More...

#include <net-snmp/net-snmp-config.h>
#include <net-snmp/types.h>

Defines
#define	NETSNMP_LARGE_FD_SET(fd, fdset) netsnmp_large_fd_setfd(fd, fdset)
	Add socket fd to the set *fdset if not yet present.
#define	NETSNMP_LARGE_FD_CLR(fd, fdset) netsnmp_large_fd_clr(fd, fdset)
	Remove socket fd from the set *fdset.
#define	NETSNMP_LARGE_FD_ISSET(fd, fdset) netsnmp_large_fd_is_set(fd, fdset)
	Test whether set *fdset contains socket fd.
#define	NETSNMP_FD_MASK_SIZE sizeof(((fd_set*)0)->fds_bits)
	Size of a single element of the array with file descriptor bitmasks.
#define	NETSNMP_BITS_PER_FD_MASK (8 * NETSNMP_FD_MASK_SIZE)
	Number of bits in one element of the fd_set::fds_bits array.
#define	NETSNMP_FD_SET_ELEM_COUNT(setsize) (setsize + NETSNMP_BITS_PER_FD_MASK - 1) / NETSNMP_BITS_PER_FD_MASK
	Number of elements needed for the fds_bits array.
#define	NETSNMP_FD_SET_BYTES(setsize) (NETSNMP_FD_SET_ELEM_COUNT(setsize) * NETSNMP_FD_MASK_SIZE)
	Number of bytes needed to store setsize file descriptors.
#define	NETSNMP_LARGE_FD_ZERO(fdset)
	Remove all file descriptors from the set *fdset.
Functions
void	netsnmp_large_fd_setfd (int fd, netsnmp_large_fd_set *fdset)
void	netsnmp_large_fd_clr (int fd, netsnmp_large_fd_set *fdset)
int	netsnmp_large_fd_is_set (int fd, netsnmp_large_fd_set *fdset)
NETSNMP_IMPORT void	netsnmp_large_fd_set_init (netsnmp_large_fd_set *fdset, int setsize)
	Initialize a netsnmp_large_fd_set structure.
void	netsnmp_large_fd_set_resize (netsnmp_large_fd_set *fdset, int setsize)
	Modify the size of a file descriptor set and preserve the first min(fdset->lfs_setsize, setsize) file descriptors.
NETSNMP_IMPORT int	netsnmp_large_fd_set_select (int numfds, netsnmp_large_fd_set readfds, netsnmp_large_fd_set writefds, netsnmp_large_fd_set exceptfds, struct timeval timeout)
	Synchronous I/O multiplexing for large file descriptor sets.
NETSNMP_IMPORT void	netsnmp_large_fd_set_cleanup (netsnmp_large_fd_set *fdset)
	Deallocate the memory allocated by netsnmp_large_fd_set_init.
void	netsnmp_copy_fd_set_to_large_fd_set (netsnmp_large_fd_set dst, const fd_set src)
	Copy an fd_set to a netsnmp_large_fd_set structure.
int	netsnmp_copy_large_fd_set_to_fd_set (fd_set dst, const netsnmp_large_fd_set src)
	Copy a netsnmp_large_fd_set structure into an fd_set.

Detailed Description

Macro's and functions for manipulation of large file descriptor sets.

Definition in file large_fd_set.h.

Define Documentation

#define NETSNMP_BITS_PER_FD_MASK (8 * NETSNMP_FD_MASK_SIZE)

Number of bits in one element of the fd_set::fds_bits array.

Definition at line 80 of file large_fd_set.h.

#define NETSNMP_FD_MASK_SIZE sizeof(((fd_set*)0)->fds_bits)

Size of a single element of the array with file descriptor bitmasks.

According to SUSv2, this array must have the name fds_bits. See also The Single UNIX Specification, Version 2, <sys/time.h>.

Definition at line 77 of file large_fd_set.h.

#define NETSNMP_FD_SET_BYTES ( setsize ) (NETSNMP_FD_SET_ELEM_COUNT(setsize) * NETSNMP_FD_MASK_SIZE)

Number of bytes needed to store setsize file descriptors.

Definition at line 87 of file large_fd_set.h.

#define NETSNMP_FD_SET_ELEM_COUNT ( setsize ) (setsize + NETSNMP_BITS_PER_FD_MASK - 1) / NETSNMP_BITS_PER_FD_MASK

Number of elements needed for the fds_bits array.

Definition at line 83 of file large_fd_set.h.

#define NETSNMP_LARGE_FD_CLR	(	fd,
		fdset
	)	netsnmp_large_fd_clr(fd, fdset)

Remove socket fd from the set *fdset.

Do nothing if fd is not present in *fdset. Do nothing if fd >= fdset->lfs_setsize.

Definition at line 42 of file large_fd_set.h.

#define NETSNMP_LARGE_FD_ISSET	(	fd,
		fdset
	)	netsnmp_large_fd_is_set(fd, fdset)

Test whether set *fdset contains socket fd.

Do nothing if fd >= fdset->lfs_setsize.

Definition at line 49 of file large_fd_set.h.

#define NETSNMP_LARGE_FD_SET	(	fd,
		fdset
	)	netsnmp_large_fd_setfd(fd, fdset)

Add socket fd to the set *fdset if not yet present.

Enlarges the set if necessary.

Definition at line 34 of file large_fd_set.h.

#define NETSNMP_LARGE_FD_ZERO ( fdset )

Value:

do {                                                     \
    int __i;                                               \
    fd_set *__arr = &(fdset)->lfs_set;                     \
    __i = NETSNMP_FD_SET_ELEM_COUNT((fdset)->lfs_setsize); \
    for ( ; __i > 0; __i--)                                \
      __arr->fds_bits[__i - 1] = 0;                        \
  } while (0)

Remove all file descriptors from the set *fdset.

Definition at line 91 of file large_fd_set.h.

Function Documentation

void netsnmp_copy_fd_set_to_large_fd_set	(	netsnmp_large_fd_set *	dst,
		const fd_set *	src
	)

Copy an fd_set to a netsnmp_large_fd_set structure.

Note:: dst must have been initialized before this function is called.

Definition at line 191 of file large_fd_set.c.

int netsnmp_copy_large_fd_set_to_fd_set	(	fd_set *	dst,
		const netsnmp_large_fd_set *	src
	)

Copy a netsnmp_large_fd_set structure into an fd_set.

Returns:: 0 upon success, -1 when copying fails because *src is too large to fit into *dst.

Definition at line 199 of file large_fd_set.c.

NETSNMP_IMPORT void netsnmp_large_fd_set_cleanup ( netsnmp_large_fd_set * fdset )

Deallocate the memory allocated by netsnmp_large_fd_set_init.

Definition at line 183 of file large_fd_set.c.

NETSNMP_IMPORT void netsnmp_large_fd_set_init	(	netsnmp_large_fd_set *	fdset,
		int	setsize
	)

Initialize a netsnmp_large_fd_set structure.

Note: this function only initializes the lfs_setsize and lfs_setptr members of netsnmp_large_fd_set, not the file descriptor set itself. The file descriptor set must be initialized separately, e.g. via NETSNMP_LARGE_FD_CLR().

Definition at line 113 of file large_fd_set.c.

void netsnmp_large_fd_set_resize	(	netsnmp_large_fd_set *	fdset,
		int	setsize
	)

Modify the size of a file descriptor set and preserve the first min(fdset->lfs_setsize, setsize) file descriptors.

Definition at line 143 of file large_fd_set.c.

NETSNMP_IMPORT int netsnmp_large_fd_set_select	(	int	numfds,
		netsnmp_large_fd_set *	readfds,
		netsnmp_large_fd_set *	writefds,
		netsnmp_large_fd_set *	exceptfds,
		struct timeval *	timeout
	)

Synchronous I/O multiplexing for large file descriptor sets.

On POSIX systems, any file descriptor set with size below numfds will be resized before invoking select().

See also:: See also select(2) for more information.

Definition at line 121 of file large_fd_set.c.

Defines

Functions

Detailed Description

Define Documentation

Function Documentation