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Diffstat (limited to 'ace/SV_Semaphore_Complex.h')
-rw-r--r-- | ace/SV_Semaphore_Complex.h | 156 |
1 files changed, 0 insertions, 156 deletions
diff --git a/ace/SV_Semaphore_Complex.h b/ace/SV_Semaphore_Complex.h deleted file mode 100644 index a5f114545a5..00000000000 --- a/ace/SV_Semaphore_Complex.h +++ /dev/null @@ -1,156 +0,0 @@ -/* -*- C++ -*- */ - -//============================================================================= -/** - * @file SV_Semaphore_Complex.h - * - * $Id$ - * - * @author Doug Schmidt - */ -//============================================================================= - - -#ifndef ACE_SV_SEMAPHORE_COMPLEX_H -#define ACE_SV_SEMAPHORE_COMPLEX_H -#include "ace/pre.h" - -#include "ace/SV_Semaphore_Simple.h" - -#if !defined (ACE_LACKS_PRAGMA_ONCE) -# pragma once -#endif /* ACE_LACKS_PRAGMA_ONCE */ - -/** - * @class ACE_SV_Semaphore_Complex - * - * @brief This is a more complex semaphore wrapper that handles race - * conditions for initialization correctly... - * - * This code is a port to C++, inspired by: W. Richard Stevens - * from his book: UNIX Network Programming (Prentice Hall, ISBN - * 0-13-949876-1 - 1990). We provide a simpler and easier to - * understand interface to the System V Semaphore system calls. - * We create and use a 2 + n-member set for the requested - * <ACE_SV_Semaphore_Complex>. The first member, [0], is a - * counter used to know when all processes have finished with - * the <ACE_SV_Semaphore_Complex>. The counter is initialized - * to a large number, decremented on every create or open and - * incremented on every close. This way we can use the "adjust" - * feature provided by System V so that any process that exit's - * without calling <close> is accounted for. It doesn't help us - * if the last process does this (as we have no way of getting - * control to remove the <ACE_SV_Semaphore_Complex>) but it - * will work if any process other than the last does an exit - * (intentional or unintentional). - * The second member, [1], of the semaphore is used as a lock - * variable to avoid any race conditions in the <create> and - * <close> functions. - * The members beyond [1] are actual semaphore values in the - * array of semaphores, which may be sized by the user in the - * constructor. - */ -class ACE_Export ACE_SV_Semaphore_Complex : private ACE_SV_Semaphore_Simple -{ -public: - enum - { - ACE_CREATE = IPC_CREAT, - ACE_OPEN = 0 - }; - - // = Initialization and termination methods. - ACE_SV_Semaphore_Complex (void); - ACE_SV_Semaphore_Complex (key_t key, - int create = ACE_SV_Semaphore_Complex::ACE_CREATE, - int initial_value = 1, - u_short nsems = 1, - int perms = ACE_DEFAULT_FILE_PERMS); - ACE_SV_Semaphore_Complex (const char *name, - int create = ACE_SV_Semaphore_Complex::ACE_CREATE, - int initial_value = 1, - u_short nsems = 1, - int perms = ACE_DEFAULT_FILE_PERMS); - ~ACE_SV_Semaphore_Complex (void); - - /// Open or create an array of SV_Semaphores. We return 0 if all is - /// OK, else -1. - int open (const char *name, - int flags = ACE_SV_Semaphore_Simple::ACE_CREATE, - int initial_value = 1, - u_short nsems = 1, - int perms = ACE_DEFAULT_FILE_PERMS); - - /// Open or create an array of SV_Semaphores. We return 0 if all is - /// OK, else -1. - int open (key_t key, - int flags = ACE_SV_Semaphore_Simple::ACE_CREATE, - int initial_value = 1, - u_short nsems = 1, - int perms = ACE_DEFAULT_FILE_PERMS); - - /** - * Close an ACE_SV_Semaphore. Unlike the <remove> method, this - * method is for a process to call before it exits, when it is done - * with the ACE_SV_Semaphore. We "decrement" the counter of - * processes using the ACE_SV_Semaphore, and if this was the last - * one, we can remove the ACE_SV_Semaphore. - */ - int close (void); - - // = Semaphore acquire and release methods. - - /// Acquire the semaphore. - int acquire (u_short n = 0, int flags = 0) const; - - /// Acquire a semaphore for reading. - int acquire_read (u_short n = 0, int flags = 0) const; - - /// Acquire a semaphore for writing - int acquire_write (u_short n = 0, int flags = 0) const; - - /// Try to acquire the semaphore. - int tryacquire (u_short n = 0, int flags = 0) const; - - /// Try to acquire the semaphore for reading. - int tryacquire_read (u_short n = 0, int flags = 0) const; - - /// Try to acquire the semaphore for writing. - int tryacquire_write (u_short n = 0, int flags = 0) const; - - /// Release the semaphore. - int release (u_short n = 0, int flags = 0) const; - - // = Semaphore operation methods. - int op (int val, u_short n = 0, int flags = 0) const; - int op (sembuf op_vec[], u_short n) const; - - // = Semaphore control methods. - int control (int cmd, semun arg, u_short n = 0) const; - int control (int cmd, int value = 0, u_short n = 0) const; - - // = Upgrade access control... - ACE_USING ACE_SV_Semaphore_Simple::get_id; - ACE_USING ACE_SV_Semaphore_Simple::remove; - - /// Dump the state of an object. - void dump (void) const; - - /// Declare the dynamic allocation hooks. - ACE_ALLOC_HOOK_DECLARE; - -private: - static const int BIGCOUNT_; - static sembuf op_lock_[2]; - static sembuf op_endcreate_[2]; - static sembuf op_open_[1]; - static sembuf op_close_[3]; - static sembuf op_unlock_[1]; -}; - -#if !defined (ACE_LACKS_INLINE_FUNCTIONS) -#include "ace/SV_Semaphore_Complex.i" -#endif - -#include "ace/post.h" -#endif /* ACE_SV_SEMAPHORE_COMPLEX_H */ |