include/sys/eventfd.h

   1 /*
   2  * This file and its contents are supplied under the terms of the
   3  * Common Development and Distribution License ("CDDL"), version 1.0.
   4  * You may only use this file in accordance with the terms of version
   5  * 1.0 of the CDDL.
   6  *
   7  * A full copy of the text of the CDDL should have accompanied this
   8  * source.  A copy of the CDDL is also available via the Internet at
   9  * http://www.illumos.org/license/CDDL.
  10  */
  11
  12 /*
  13  * Copyright (c) 2015 Joyent, Inc.  All rights reserved.
  14  */
  15
  16 /*
  17  * Header file to support for the eventfd facility.  Note that this facility
  18  * is designed to be binary compatible with the Linux eventfd facility; values
  19  * for constants here should therefore exactly match those found in Linux, and
  20  * this facility shouldn't be extended independently of Linux.
  21  */
  22
  23 #ifndef _SYS_EVENTFD_H
  24 #define _SYS_EVENTFD_H
  25
  26 #include <sys/types.h>
  27
  28 #ifdef  __cplusplus
  29 extern "C" {
  30 #endif
  31
  32 typedef uint64_t eventfd_t;
  33
  34 /*
  35  * To assure binary compatibility with Linux, these values are fixed at their
  36  * Linux equivalents, not their native ones.
  37  */
  38 #define EFD_CLOEXEC             02000000                /* LX_O_CLOEXEC */
  39 #define EFD_NONBLOCK            04000                   /* LX_O_NONBLOCK */
  40 #define EFD_SEMAPHORE           1
  41
  42 /*
  43  * These ioctl values are specific to the native implementation; applications
  44  * shouldn't be using them directly, and they should therefore be safe to
  45  * change without breaking apps.
  46  */
  47 #define EVENTFDIOC              (('e' << 24) | ('f' << 16) | ('d' << 8))
  48 #define EVENTFDIOC_SEMAPHORE    (EVENTFDIOC | 1)        /* toggle sem state */
  49
  50 #ifndef _KERNEL
  51
  52 extern int eventfd(unsigned int, int);
  53 extern int eventfd_read(int, eventfd_t *);
  54 extern int eventfd_write(int, eventfd_t);
  55
  56 #else
  57
  58 #define EVENTFDMNRN_EVENTFD     0
  59 #define EVENTFDMNRN_CLONE       1
  60 #define EVENTFD_VALMAX          (ULLONG_MAX - 1ULL)
  61
  62 #endif /* _KERNEL */
  63
  64 #ifdef  __cplusplus
  65 }
  66 #endif
  67
  68 #endif  /* _SYS_EVENTFD_H */