ACE/ace/os_include/os_semaphore.h

   1 // -*- C++ -*-
   2
   3 //=============================================================================
   4 /**
   5  *  @file    os_semaphore.h
   6  *
   7  *  semaphores (REALTIME)
   8  *
   9  *  @author Don Hinton <dhinton@dresystems.com>
  10  *  @author This code was originally in various places including ace/OS.h.
  11  */
  12 //=============================================================================
  13
  14 #ifndef ACE_OS_INCLUDE_OS_SEMAPHORE_H
  15 #define ACE_OS_INCLUDE_OS_SEMAPHORE_H
  16
  17 #include /**/ "ace/pre.h"
  18
  19 #include /**/ "ace/config-all.h"
  20
  21 #if !defined (ACE_LACKS_PRAGMA_ONCE)
  22 # pragma once
  23 #endif /* ACE_LACKS_PRAGMA_ONCE */
  24
  25 #include "ace/os_include/os_time.h"
  26
  27 #if !defined (ACE_LACKS_SEMAPHORE_H)
  28 # include /**/ <semaphore.h>
  29 #endif /* !ACE_LACKS_SEMAPHORE_H */
  30
  31 // Place all additions (especially function declarations) within extern "C" {}
  32 #ifdef __cplusplus
  33 extern "C"
  34 {
  35 #endif /* __cplusplus */
  36
  37 #if defined (ACE_HAS_POSIX_SEM)
  38 #  if !defined (SEM_FAILED) && !defined (ACE_LACKS_NAMED_POSIX_SEM)
  39 #    define SEM_FAILED ((sem_t *) -1)
  40 #  endif  /* !SEM_FAILED */
  41
  42    typedef struct
  43    {
  44      /// Pointer to semaphore handle.  This is allocated by ACE if we are
  45      /// working with an unnamed POSIX semaphore or by the OS if we are
  46      /// working with a named POSIX semaphore.
  47      sem_t *sema_;
  48
  49      /// Name of the semaphore (if this is non-NULL then this is a named
  50      /// POSIX semaphore, else its an unnamed POSIX semaphore).
  51      char *name_;
  52
  53      /// Do not unlink the named semaphore.  This lets the logical entity
  54      /// of the semaphore outlive any one process that opens it.  The semaphore
  55      /// must be manually unlinked with ACE_OS::sema_unlink().
  56      bool avoid_unlink_;
  57
  58 #  if defined (ACE_LACKS_NAMED_POSIX_SEM)
  59      /// this->sema_ doesn't always get created dynamically if a platform
  60      /// doesn't support named posix semaphores.  We use this flag to
  61      /// remember if we need to delete <sema_> or not.
  62      bool new_sema_;
  63 #  endif /* ACE_LACKS_NAMED_POSIX_SEM */
  64
  65 #  if !defined (ACE_HAS_POSIX_SEM_TIMEOUT) && !defined (ACE_DISABLE_POSIX_SEM_TIMEOUT_EMULATION)
  66      /// Serialize access to internal state.
  67      ACE_mutex_t lock_;
  68
  69      /// Block until there are no waiters.
  70      ACE_cond_t count_nonzero_;
  71 #  endif /* !ACE_HAS_POSIX_SEM_TIMEOUT && !ACE_DISABLE_POSIX_SEM_TIMEOUT_EMULATION */
  72    } ACE_sema_t;
  73 #endif /* ACE_HAS_POSIX_SEM */
  74
  75 #ifdef __cplusplus
  76 }
  77 #endif /* __cplusplus */
  78
  79 #include /**/ "ace/post.h"
  80 #endif /* ACE_OS_INCLUDE_OS_SEMAPHORE_H */