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Diffstat (limited to 'nuttx/include/sys/select.h')
-rw-r--r-- | nuttx/include/sys/select.h | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/nuttx/include/sys/select.h b/nuttx/include/sys/select.h new file mode 100644 index 000000000..1ff074b6c --- /dev/null +++ b/nuttx/include/sys/select.h @@ -0,0 +1,121 @@ +/**************************************************************************** + * include/sys/select.h + * + * Copyright (C) 2008-2009, 2011 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 __SELECT_NDESCRIPTORS (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 __SELECT_NDESCRIPTORS <= 32 +# define __SELECT_NUINT32 1 +#elif __SELECT_NDESCRIPTORS <= 64 +# define __SELECT_NUINT32 2 +#elif __SELECT_NDESCRIPTORS <= 96 +# define __SELECT_NUINT32 3 +#elif __SELECT_NDESCRIPTORS <= 128 +# define __SELECT_NUINT32 4 +#elif __SELECT_NDESCRIPTORS <= 160 +# define __SELECT_NUINT32 5 +#elif __SELECT_NDESCRIPTORS <= 192 +# define __SELECT_NUINT32 6 +#elif __SELECT_NDESCRIPTORS <= 224 +# define __SELECT_NUINT32 7 +#elif __SELECT_NDESCRIPTORS <= 256 +# define __SELECT_NUINT32 8 +#else +# warning "Large fd_set needed" +#endif + +/* These macros map a file descripto 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) (((uint32_t*)(set))[_FD_NDX(fd)] &= ~(1 << _FD_BIT(fd))) +#define FD_SET(fd,set) (((uint32_t*)(set))[_FD_NDX(fd)] |= (1 << _FD_BIT(fd))) +#define FD_ISSET(fd,set) ((((uint32_t*)(set))[_FD_NDX(fd)] & (1 << _FD_BIT(fd))) != 0) +#define FD_ZERO(set) memset(set, 0, sizeof(fd_set)) + +/**************************************************************************** + * Type Definitions + ****************************************************************************/ + +typedef uint32_t fd_set[__SELECT_NUINT32]; + +/**************************************************************************** + * Public Function Prototypes + ****************************************************************************/ + +#undef EXTERN +#if defined(__cplusplus) +#define EXTERN extern "C" +extern "C" { +#else +#define EXTERN extern +#endif + +EXTERN 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 */ |