/****************************************************************************
* include/sys/select.h
*
* Copyright (C) 2008-2009, 2011, 2015 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
#ifndef __INCLUDE_SYS_SELECT_H
#define __INCLUDE_SYS_SELECT_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include <time.h>
#if CONFIG_NFILE_DESCRIPTORS > 0 || CONFIG_NSOCKET_DESCRIPTORS > 0
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Get the total number of descriptors that we will have to support */
#define FD_SETSIZE (CONFIG_NFILE_DESCRIPTORS + CONFIG_NSOCKET_DESCRIPTORS)
/* We will use a 32-bit bitsets to represent the set of descriptors. How
* many uint32_t's do we need to span all descriptors?
*/
#if FD_SETSIZE <= 32
# define __SELECT_NUINT32 1
#elif FD_SETSIZE <= 64
# define __SELECT_NUINT32 2
#elif FD_SETSIZE <= 96
# define __SELECT_NUINT32 3
#elif FD_SETSIZE <= 128
# define __SELECT_NUINT32 4
#elif FD_SETSIZE <= 160
# define __SELECT_NUINT32 5
#elif FD_SETSIZE <= 192
# define __SELECT_NUINT32 6
#elif FD_SETSIZE <= 224
# define __SELECT_NUINT32 7
#elif FD_SETSIZE <= 256
# define __SELECT_NUINT32 8
#else
# warning "Larger fd_set needed"
#endif
/* These macros map a file descriptor to an index and bit number */
#define _FD_NDX(fd) ((fd) >> 5)
#define _FD_BIT(fd) ((fd) & 0x1f)
/* Standard helper macros */
#define FD_CLR(fd,set) \
((((fd_set*)(set))->arr)[_FD_NDX(fd)] &= ~(1 << _FD_BIT(fd)))
#define FD_SET(fd,set) \
((((fd_set*)(set))->arr)[_FD_NDX(fd)] |= (1 << _FD_BIT(fd)))
#define FD_ISSET(fd,set) \
(((((fd_set*)(set))->arr)[_FD_NDX(fd)] & (1 << _FD_BIT(fd))) != 0)
#define FD_ZERO(set) \
memset((set), 0, sizeof(fd_set))
/****************************************************************************
* Type Definitions
****************************************************************************/
struct fd_set_s
{
uint32_t arr[__SELECT_NUINT32];
};
typedef struct fd_set_s fd_set;
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
#undef EXTERN
#if defined(__cplusplus)
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
struct timeval;
int select(int nfds, FAR fd_set *readfds, FAR fd_set *writefds,
FAR fd_set *exceptfds, FAR struct timeval *timeout);
#undef EXTERN
#if defined(__cplusplus)
}
#endif
#endif /* CONFIG_NFILE_DESCRIPTORS || CONFIG_NSOCKET_DESCRIPTORS */
#endif /* __INCLUDE_SYS_SELECT_H */
