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Diffstat (limited to 'ACE/ace/Process_Mutex.h')
-rw-r--r-- | ACE/ace/Process_Mutex.h | 216 |
1 files changed, 0 insertions, 216 deletions
diff --git a/ACE/ace/Process_Mutex.h b/ACE/ace/Process_Mutex.h deleted file mode 100644 index c2fb3c702da..00000000000 --- a/ACE/ace/Process_Mutex.h +++ /dev/null @@ -1,216 +0,0 @@ -// -*- C++ -*- - -//============================================================================= -/** - * @file Process_Mutex.h - * - * $Id$ - * - * A wrapper for mutexes that can be used across processes on the - * same host machine, as well as within a process, of course. - * - * @author Douglas C. Schmidt <schmidt@uci.edu> - */ -//============================================================================= - -#ifndef ACE_PROCESS_MUTEX_H -#define ACE_PROCESS_MUTEX_H - -#include /**/ "ace/pre.h" - -#include /**/ "ace/config-all.h" - -#if !defined (ACE_LACKS_PRAGMA_ONCE) -# pragma once -#endif /* ACE_LACKS_PRAGMA_ONCE */ - -// To make it easier to carry the setting though this file as well as -// Process_Mutex.{cpp inl}, set a private macro here. -#ifdef _ACE_USE_SV_SEM -# undef _ACE_USE_SV_SEM -#endif /* _ACE_USE_SV_SEM */ - -#if defined (ACE_HAS_SYSV_IPC) && !defined (ACE_USES_MUTEX_FOR_PROCESS_MUTEX) -# include "ace/SV_Semaphore_Complex.h" -# define _ACE_USE_SV_SEM -#else -# include "ace/Mutex.h" -#endif /* ACE_HAS_SYSV_IPC && !ACE_USES_MUTEX_FOR_PROCESS_MUTEX */ - -ACE_BEGIN_VERSIONED_NAMESPACE_DECL - -// Forward declarations -class ACE_Time_Value; - -/** - * @class ACE_Process_Mutex - * - * @brief A wrapper for mutexes that can be used across processes on - * the same host machine, as well as within a process, of - * course. - * - * @attention The mechanism upon which @c ACE_Process_Mutex is based - * can be configured at build time to be either @c ACE_SV_Semaphore_Complex - * (on platforms that support it) or @c ACE_Mutex. On platforms that - * require interprocess mutexes be allocated from shared memory (Pthreads - * and UI Threads are examples), @c ACE_SV_Semaphore_Complex provides a - * more reliable mechanism for implementing inter-process mutex than - * @c ACE_Mutex. However, at least on some platforms, - * @c ACE_SV_Semaphore_Complex is limited to a small number of - * objects by the underlying System V IPC kernel parameters. If you - * want to force use of @c ACE_Mutex as the underlying mechanism, set - * @c ACE_USES_MUTEX_FOR_PROCESS_MUTEX in your @c config.h file. - * Also, if you require the ability to do a timed @c acquire(), you must - * set @c ACE_USES_MUTEX_FOR_PROCESS_MUTEX, as timed acquire does not - * work with System V semaphores. - * @attention Currently there is also the operational difference between - * pthreads and semaphores based @c. For semaphore base @c the semaphore - * is destroyed after the last instance of @c in OS. In contrary, pthread based - * @c is destroyed when the owner, namely the process which created the - * first instance of @c destroys the mutex. For protable applications it is better - * to always ensure that the owner of the mutex destroys it after the - * other processes. - */ -class ACE_Export ACE_Process_Mutex -{ -public: - /** - * Create a Process_Mutex, passing in the optional @c name. - * - * @param name optional, null-terminated string containing the name of - * the object. Multiple users of the same @c ACE_Process_Mutex must use - * the same name to access the same object. If not specified, a name - * is generated. - * @param arg optional, attributes to be used to initialize the mutex. - * If using @c ACE_SV_Semaphore_Complex as the underlying mechanism, - * this argument is ignored. - * @param mode optional, the protection mode for either the backing store - * file (for ACE_Mutex use) or the ACE_SV_Semaphore_Complex that's created. - */ - ACE_Process_Mutex (const char *name = 0, - void *arg = 0, - mode_t mode = ACE_DEFAULT_FILE_PERMS); - -#if defined (ACE_HAS_WCHAR) - /** - * Create a Process_Mutex, passing in the optional @c name. (@c wchar_t - * version) - * - * @param name optional, null-terminated string containing the name of - * the object. Multiple users of the same @c ACE_Process_Mutex must use - * the same name to access the same object. If not specified, a name - * is generated. - * @param arg optional, attributes to be used to initialize the mutex. - * If using @c ACE_SV_Semaphore_Complex as the underlying mechanism, - * this argument is ignored. - * @param mode optional, the protection mode for either the backing store - * file (for ACE_Mutex use) or the ACE_SV_Semaphore_Complex that's created. - */ - ACE_Process_Mutex (const wchar_t *name, - void *arg = 0, - mode_t mode = ACE_DEFAULT_FILE_PERMS); -#endif /* ACE_HAS_WCHAR */ - - ~ACE_Process_Mutex (void); - - /** - * Explicitly destroy the mutex. Note that only one thread should - * call this method since it doesn't protect against race - * conditions. - * - * @return 0 on success; -1 on failure. - */ - int remove (void); - - /** - * Acquire lock ownership (wait on queue if necessary). - * - * @return 0 on success; -1 on failure. - */ - int acquire (void); - - /** - * Acquire lock ownership, but timeout if lock if hasn't been - * acquired by given time. - * - * @param tv the absolute time until which the caller is willing to - * wait to acquire the lock. - * - * @return 0 on success; -1 on failure. - */ - int acquire (ACE_Time_Value &tv); - - /** - * Conditionally acquire lock (i.e., don't wait on queue). - * - * @return 0 on success; -1 on failure. If the lock could not be acquired - * because someone else already had the lock, @c errno is set to @c EBUSY. - */ - int tryacquire (void); - - /// Release lock and unblock a thread at head of queue. - int release (void); - - /// Acquire lock ownership (wait on queue if necessary). - int acquire_read (void); - - /// Acquire lock ownership (wait on queue if necessary). - int acquire_write (void); - - /** - * Conditionally acquire a lock (i.e., won't block). Returns -1 on - * failure. If we "failed" because someone else already had the - * lock, @c errno is set to @c EBUSY. - */ - int tryacquire_read (void); - - /** - * Conditionally acquire a lock (i.e., won't block). Returns -1 on - * failure. If we "failed" because someone else already had the - * lock, @c errno is set to @c EBUSY. - */ - int tryacquire_write (void); - - /** - * This is only here for consistency with the other synchronization - * APIs and usability with Lock adapters. Assumes the caller already has - * acquired the mutex and returns 0 in all cases. - */ - int tryacquire_write_upgrade (void); - -#if !defined (_ACE_USE_SV_SEM) - /// Return the underlying mutex. - const ACE_mutex_t &lock (void) const; -#endif /* !_ACE_USE_SV_SEM */ - - /// Dump the state of an object. - void dump (void) const; - - /// Declare the dynamic allocation hooks. - ACE_ALLOC_HOOK_DECLARE; - -private: - /// If the user does not provide a name we generate a unique name in - /// this buffer. - ACE_TCHAR name_[ACE_UNIQUE_NAME_LEN]; - - /// Create and return the unique name. - const ACE_TCHAR *unique_name (void); - -#if defined (_ACE_USE_SV_SEM) - /// We need this to get the right semantics... - ACE_SV_Semaphore_Complex lock_; -#else - ACE_Mutex lock_; -#endif /* _ACE_USE_SV_SEM */ -}; - -ACE_END_VERSIONED_NAMESPACE_DECL - -#if defined (__ACE_INLINE__) -#include "ace/Process_Mutex.inl" -#endif /* __ACE_INLINE__ */ - -#include /**/ "ace/post.h" - -#endif /* ACE_PROCESS_MUTEX_H */ |