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Diffstat (limited to 'ace/Local_Tokens.h')
| -rw-r--r-- | ace/Local_Tokens.h | 972 |
1 files changed, 0 insertions, 972 deletions
diff --git a/ace/Local_Tokens.h b/ace/Local_Tokens.h deleted file mode 100644 index e4ebe99a2b6..00000000000 --- a/ace/Local_Tokens.h +++ /dev/null @@ -1,972 +0,0 @@ -/* -*- C++ -*- */ -// $Id$ - -// ============================================================================ -// -// = LIBRARY -// ace -// -// = FILENAME -// Local_Tokens -// -// = AUTHOR -// Karl-Heinz Dorn (kdorn@erlh.siemens.de) -// Douglas C. Schmidt (schmidt@cs.wustl.edu) -// Tim Harrison (harrison@cs.wustl.edu) -// -// = DESCRIPTION -// This file contains definitions for the following classes: -// -// public: -// 7. ACE_Token_Proxy -// 8. ACE_Null_Token : public ACE_Token_Proxy -// 9. ACE_Local_Mutex : public ACE_Token_Proxy -// *. ACE_Local_RLock : public ACE_Local_Mutex -// &. ACE_Local_WLock : public ACE_Local_Mutex -// private: -// 1. ACE_TOKEN_CONST -// 3. ACE_TPQ_Entry -// b. ACE_TSS_TPQ_Entry -// c. ACE_TPQ_Iterator -// 4. ACE_Token_Proxy_Queue -// 5. ACE_Tokens -// 6. ACE_Mutex_Token : public ACE_Tokens -// 12. ACE_RW_Token : public ACE_Tokens -// a. ACE_Token_Name -// -// ============================================================================ - -#if !defined (ACE_LOCAL_MUTEX_H) -#define ACE_LOCAL_MUTEX_H - -#include "ace/Synch.h" -#include "ace/Stack.h" -#include "ace/Synch_Options.h" -#include "ace/Map_Manager.h" - -// 1. -class ACE_Export ACE_TOKEN_CONST -{ - // = TITLE - // Not a public interface. - // - // = DESCRIPTION - // Constant definitions and typdefs for Token library. Mostly, - // this class is necessary to fight the compiler with order of - // declaration errors. -public: -#if defined (ACE_MT_SAFE) - // ACE platform supports some form of threading. - typedef ACE_Condition_Thread_Mutex COND_VAR; - typedef ACE_Thread_Mutex MUTEX; - typedef ACE_Thread_Mutex_Guard GUARD; -#else - typedef ACE_Null_Condition_Mutex COND_VAR; - typedef ACE_Null_Mutex MUTEX; - typedef ACE_Null_Mutex_Guard GUARD; -#endif /* ACE_HAS_THREADS */ -}; - -// Forward decl. -class ACE_Token_Proxy; - -// 3.. -class ACE_Export ACE_TPQ_Entry - // = TITLE - // Not a public interface. - // - // = DESCRIPTION - // Token Proxy Queue entry. - // Used in the ACE_Token_Proxy_Queue -{ -friend class ACE_Token_Manager; -public: - typedef void (*PTVF) (void *); - - ACE_TPQ_Entry (void); - // Null constructor. - - ACE_TPQ_Entry (const ACE_Token_Proxy *proxy, - const char *client_id); - // Construction. - - ACE_TPQ_Entry (const ACE_TPQ_Entry &rhs); - // Copy constructor. - - ~ACE_TPQ_Entry (void); - // Death. - - void operator= (const ACE_TPQ_Entry &rhs); - // Copy operator use by the queue. - - // = Set/get top of the queue. - ACE_Token_Proxy *proxy (void) const; - void proxy (ACE_Token_Proxy *); - - // = Delta/get nesting level of the entry. - int nesting_level (void) const; - void nesting_level (int delta); - - // = Set/get client_id of the entry. - const char *client_id (void) const; - void client_id (const char *); - - int equal_client_id (const char *id); - // Returns 1 if <id> == client id. Does not check for <id> == 0. - - void set (void (*sleep_hook)(void *)); - // One method for arg and sleep_hook. - - // = Set/get sleep hook of the entry. - void sleep_hook (void (*sh)(void *)); - PTVF sleep_hook (void) const; - - void call_sleep_hook (void); - // Call the sleep hook function or method passing arg. - - void dump (void) const; - // Dump the state of the class. - - // = Used to block the thread if an acquire fails with EWOULDBLOCK. - ACE_TOKEN_CONST::COND_VAR cond_var_; - ACE_TOKEN_CONST::MUTEX lock_; - - ACE_TPQ_Entry *next_; - // Pointer to next in list. - - // = Get/set whether this client is blocked waiting for a token. - int waiting (void) const; - void waiting (int w); - -private: - int waiting_; - // This client is waiting for a token. - - ACE_Token_Proxy *proxy_; - // Proxy. - - int nesting_level_; - // Nesting level. - - void *arg_; - // Arg. - - char client_id_[ACE_MAXCLIENTIDLEN]; - // Client id. - - void (*sleep_hook_)(void *); - // Sleep hook. -}; - -// ************************************************************ - -// b.. -#if defined (ACE_NO_TSS_TOKENS) -typedef ACE_TPQ_Entry ACE_TPQ_ENTRY; -#else -typedef ACE_TSS<ACE_TPQ_Entry> ACE_TPQ_ENTRY; -#endif /* ACE_NO_TSS_TOKENS */ - -class ACE_Export ACE_TSS_TPQ_Entry : public ACE_TPQ_ENTRY - // = TITLE - // Not a public interface. - // = DESCRIPTION - // ACE_TSS_TPQ_Entry -{ -public: - ACE_TSS_TPQ_Entry (const ACE_Token_Proxy *proxy, - const char *client_id); - // These are passed to the constructor of ACE_TPQ_Entry in - // make_TSS_TYPE - - virtual ACE_TPQ_Entry *make_TSS_TYPE (void) const; - // Allows us to pass args to the construction of the TSS object. - - operator ACE_TPQ_Entry *(void); - // Operator overloading and inheritence don't mix. - - void dump (void) const; - // Dump the state of the class. - -#if defined (ACE_NO_TSS_TOKENS) - ACE_TSS_TPQ_Entry *operator-> (void) - { - return this; - } -#endif - -private: - // = These are passed to the constructor of ACE_TPQ_Entry in - // make_TSS_TYPE - const ACE_Token_Proxy *proxy_; - // Proxy. - const char *client_id_; - // Client_id. -}; - -// ************************************************************ - -class ACE_Token_Proxy_Queue; - -// c.. -class ACE_Export ACE_TPQ_Iterator - // = TITLE - // Not a public interface. - // - // = DESCRIPTION - // Iterates through ACE_Token_Proxy_Queues. -{ -public: - ACE_TPQ_Iterator (ACE_Token_Proxy_Queue &q); - // Construction. - - int next (ACE_TPQ_Entry *&next_item); - // Pass back the <next_item>. Returns 0 when all items have been - // seen, else 1. - - void advance (void); - // Move forward by one element in the queue. - - void dump (void) const; - // Dump the state of an object. - -private: - ACE_TPQ_Entry *current_; -}; - -// 4.. -class ACE_Export ACE_Token_Proxy_Queue - // = TITLE - // Not a public interface. - // - // = DESCRIPTION - // Token waiter list. - // This queue holds all the token proxies waiting for ownership of - // a token. Along with the proxy reference, it also stores the - // nesting level, client id, and a magic cookie from the proxy. - // This queue stores the ACE_TPQ_Entries by pointer values. It - // DOES NOT make copies. Thus, the user is responsible to ensure - // that the TPQ's stick around. This is motivated by the need to - // reduce dynamic memory allocation. -{ - friend class ACE_TPQ_Iterator; -public: - ACE_Token_Proxy_Queue (void); - // Construction. - - void enqueue (ACE_TPQ_Entry* new_entry, - int position); - // Enqueue a proxy, nesting level, client_id, and a magic cookie at - // the given position in the list. If the position is -1, we - // enqueue at the end of the list (I think). - - const ACE_TPQ_Entry* head (void); - // Top of the queue. - -// int member (const char *id); - // Is this id in the waiter list? - - void dequeue (void); - // Remove the top waiter. - - void remove (const ACE_TPQ_Entry *remove_me); - // Remove the waiter whose proxy ref matches remove_me. - - int size (void); - // The number of waiters. - - void dump (void) const; - // Dump the state of the class. - -protected: - ACE_TPQ_Entry *head_; - // Head. - ACE_TPQ_Entry *tail_; - // Tail. - int size_; - // Size. -}; - -// 5.. -class ACE_Export ACE_Tokens - // = TITLE - // Not a public interface. - // - // = DESCRIPTION - // Abstract representation of ACE tokens. - // Currently, I don't see a reason for providing an abstract - // interface at this level of the library. As of yet, no one uses - // ACE_Tokens derivatives through this abstract interface except - // for Token_Manager. It only uses the statistical methods which - // are shared by all Tokens. For that reason, it still makes - // since to have a common base class. However, acquire, renew, - // and release do not need to have matching interfaces throughout - // all Tokens. - - // = EXTENDING TOKENS - // To add a new type of token (e.g. semaphore), this class must be - // subtyped to define the new semantics. See ACE_Token_Manager - // for details. -{ -public: - - ACE_Tokens (void); - // Null constructor. - - virtual int acquire (ACE_TPQ_Entry *caller, - int ignore_deadlock, - int notify) = 0; - // No implementation. - - virtual int tryacquire (ACE_TPQ_Entry *caller) = 0; - // No implementation. - - virtual int renew (ACE_TPQ_Entry *caller, - int requeue_position) = 0; - // No implementation. - - virtual int release (ACE_TPQ_Entry *caller) = 0; - // No implementation. - - void make_owner (ACE_TPQ_Entry *caller); - // Move the caller to the front of the waiter list. This is for use - // with remote mutexes and shadow mutexes. - - void remove (ACE_TPQ_Entry *caller); - // Remove the caller from the waiter list. - - // = Accessor methods. - - typedef ACE_Unbounded_Stack<ACE_TPQ_Entry *> OWNER_STACK; - // Stack of owners. - - virtual int owners (OWNER_STACK &o, const char *id) = 0; - // Returns a stack of the current owners. Returns -1 on error, 0 on - // success. If <id> is non-zero, returns 1 if id is an owner. - - virtual int is_waiting_for (const char *id) = 0; - // Returns 1 if <id> is waiting for this token. 0 otherwise. - - virtual int is_owner (const char *id) = 0; - // Returns 1 if <id> is an owner of this token. 0 otherwise. - - virtual ACE_Token_Proxy_Queue *waiters (void); - // Return the queue of waiters. - - virtual int no_of_waiters (void); - // Return the number of proxies that are currently waiting to get - // the token. - - const char *owner_id (void); - // The current owner. - - const char* name (void); - // Token name. - - // = Reference counting. These are only called by the - // Token_Manager. - void inc_reference (void); - int dec_reference (void); - - void dump (void) const; - // Dump the state of the class. - - enum TOKEN_TYPES { MUTEX, RWLOCK }; - // These are the Token types supported by the library at ship time. - // There is no restriction on the number of Token types added by - // "3rd parties." These are only necessary for the Token Server. - - virtual int type (void) const = 0; - // Provides a manual RTTI mechanism. This method is used only by - // ACE_Token_Request so that the type of a token can be sent to a - // remote Token Server. - - // = The following methods allow the deadlock detection algorithm to - // check if this token has been visited. - - void visit (int v); - // Mark or unmark the token as visited. - - int visited (void); - // Check if the token has been visited. - - ACE_TPQ_Entry *owner (void); - // All the data of the current owner. - -protected: - - int visited_; - // For the deadlock detection algorithm. - - int reference_count_; - // Reference count. - - ACE_Token_Proxy_Queue waiters_; - // List of client's owning and waiting the token. - - char token_name_[ACE_MAXTOKENNAMELEN]; - // Name of token. -}; - -class ACE_Local_Mutex; - -// 6.. -class ACE_Export ACE_Mutex_Token : public ACE_Tokens - // = TITLE - // Not a public interface. - // - // = DESCRIPTION - // Class that acquires, renews, and releases a process-local - // synchronization token. - // This class is a more general-purpose synchronization mechanism - // than SunOS 5.x mutexes. For example, it implements "recursive - // mutex" semantics, where a thread that owns the token can - // reacquire it without deadlocking. In addition, threads that are - // blocked awaiting the token are serviced in strict FIFO order as - // other threads release the token (SunOS 5.x mutexes don't strictly - // enforce an acquisition order). -{ -public: - ACE_Mutex_Token (const char* name); - // life - - virtual ~ACE_Mutex_Token (void); - // death - - // = Synchronization operations. - // With acquire, renew, and release, the caller must be specified so - // that multiple proxies (e.g. ACE_Local_Mutex) can use the same - // token. - - virtual int acquire (ACE_TPQ_Entry *caller, - int ignore_deadlock, - int notify); - // Returns 0 on success, -1 on failure with ACE_LOG_MSG->errnum() as - // the reason. If errnum == EWOULDBLOCK, and notify == 1, - // ACE_Token_Proxy::sleep_hook() has been called on the current owner - // of the token. If ignore_deadlock is passed as 1 and errnum == - // EDEADLK, then deadlock was detected via ace_token_manager. - - virtual int tryacquire (ACE_TPQ_Entry *caller); - // same as acquire, but fails if would block - - virtual int renew (ACE_TPQ_Entry *caller, - int requeue_position); - // An optimized method that efficiently reacquires the token if no - // other threads are waiting. This is useful for situations where - // you don't want to degrade the quality of service if there are - // other threads waiting to get the token. If <requeue_position> == - // -1 and there are other threads waiting to obtain the token we are - // queued at the end of the list of waiters. If <requeue_position> - // > -1 then it indicates how many entries to skip over before - // inserting our thread into the list of waiters (e.g., - // <requeue_position> == 0 means "insert at front of the queue"). - // Renew has the rather odd semantics such that if there are other - // waiting threads it will give up the token even if the - // nesting_level_ > 1. I'm not sure if this is really the right - // thing to do (since it makes it possible for shared data to be - // changed unexpectedly) so use with caution... - // Returns 0 on success, -1 on failure with ACE_LOG_MSG->errnum() as - // the reason. If errnum == EWOULDBLOCK, and notify == 1, - // ACE_Token_Proxy::sleep_hook() has been called on the current owner - // of the token. - - virtual int release (ACE_TPQ_Entry *caller); - // Relinquish the token. If there are any waiters then the next one - // in line gets it. If the caller is not the owner, caller is - // removed from the waiter list. - - void dump (void) const; - // Dump the state of the class. - - virtual int type (void) const; - // Returns ACE_Tokens::MUTEX. - - virtual int owners (OWNER_STACK &o, const char *id); - // Returns a stack of the current owners. Returns -1 on error, 0 on - // success. If <id> is non-zero, returns 1 if id is an owner. - - virtual int is_waiting_for (const char *id); - // Returns 1 if <id> is waiting for this token. 0 otherwise. - - virtual int is_owner (const char *id); - // Returns 1 if <id> is an owner of this token. 0 otherwise. - -private: - ACE_TOKEN_CONST::MUTEX lock_; - // ACE_Mutex_Token used to lock internal data structures. -}; - -// 12.. -class ACE_Export ACE_RW_Token : public ACE_Tokens - // = TITLE - // Not a public interface. - // - // = DESCRIPTION - // Class that acquires, renews, and releases a process-local - // synchronization token. - // This class is a more general-purpose synchronization mechanism - // than SunOS 5.x mutexes. For example, it implements "recursive - // mutex" semantics, where a thread that owns the token can - // reacquire it without deadlocking. In addition, threads that are - // blocked awaiting the token are serviced in strict FIFO order as - // other threads release the token (SunOS 5.x mutexes don't strictly - // enforce an acquisition order). -{ -public: - ACE_RW_Token (const char* name); - // Life. - - virtual ~ACE_RW_Token (void); - // Death. - - // = Synchronization operations. - // With acquire, renew, and release, the caller must be specified so - // that multiple proxies (e.g. ACE_Local_Mutex) can use the same - // token. - - virtual int acquire (ACE_TPQ_Entry *caller, - int ignore_deadlock, - int notify); - // Returns 0 on success, -1 on failure with ACE_LOG_MSG->errnum() as - // the reason. If errnum == EWOULDBLOCK, and notify == 1, - // ACE_Token_Proxy::sleep_hook() has been called on the current owner - // of the token. If ignore_deadlock is passed as 1 and errnum == - // EDEADLK, then deadlock was detected via ace_token_manager. - - virtual int tryacquire (ACE_TPQ_Entry *caller); - // same as acquire except fails on would block - - virtual int renew (ACE_TPQ_Entry *caller, - int requeue_position); - // An optimized method that efficiently reacquires the token if no - // other threads are waiting. This is useful for situations where - // you don't want to degrade the quality of service if there are - // other threads waiting to get the token. If <requeue_position> == - // -1 and there are other threads waiting to obtain the token we are - // queued at the end of the list of waiters. If <requeue_position> - // > -1 then it indicates how many entries to skip over before - // inserting our thread into the list of waiters (e.g., - // <requeue_position> == 0 means "insert at front of the queue"). - // Renew has the rather odd semantics such that if there are other - // waiting threads it will give up the token even if the - // nesting_level_ > 1. I'm not sure if this is really the right - // thing to do (since it makes it possible for shared data to be - // changed unexpectedly) so use with caution... - // Returns 0 on success, -1 on failure with ACE_LOG_MSG->errnum() as - // the reason. If errnum == EWOULDBLOCK, and notify == 1, - // ACE_Token_Proxy::sleep_hook() has been called on the current owner - // of the token. - - virtual int release (ACE_TPQ_Entry *caller); - // Relinquish the token. If there are any waiters then the next one - // in line gets it. If the caller is not the owner, caller is - // removed from the waiter list. - - void dump (void) const; - // Dump the state of the class. - - enum PROXY_TYPE { READER, WRITER }; - // These are the types that proxies can be. - - virtual int type (void) const; - // Returns READER or WRITER. - - virtual int owners (OWNER_STACK &o, const char *id); - // Returns a stack of the current owners. Returns -1 on error, 0 on - // success. If <id> is non-zero, returns 1 if id is an owner. - - virtual int is_waiting_for (const char *id); - // Returns 1 if <id> is waiting for this token. 0 otherwise. - - virtual int is_owner (const char *id); - // Returns 1 if <id> is an owner of this token. 0 otherwise. - -protected: - int num_writers_; - // the number of waiting writers. - - ACE_TOKEN_CONST::MUTEX lock_; - // ACE_Mutex_Token used to lock internal data structures. - - void notify_new_owner (ACE_TPQ_Entry *caller); - // Sets the new owner. -}; - -// a.. -class ACE_Token_Name - // = TITLE - // Allows Token_Manger to identify tokens. - // - // = DESCRIPTION - // For now, this is just a string. We need a string class anyway - // to use in ACE_Map_Manager. Having this class (instead of - // SString) allows us to easily change if needed. For instance, - // we may choose to identify tokens by name and *type* in the - // future. -{ -public: - ACE_Token_Name (const char *token_name = 0); - // Construction. - - ACE_Token_Name (const ACE_Token_Name &rhs); - // Copy construction. - - virtual ~ACE_Token_Name (void); - // Death. - - void operator= (const ACE_Token_Name &rhs); - // Copy. - - int operator== (const ACE_Token_Name &rhs) const; - // Comparison. - - const char *name (void) const; - // Token name. - - void name (const char *new_name); - // Token name. - - void dump (void) const; - // Dump the state of the class. - -private: - char token_name_[ACE_MAXTOKENNAMELEN]; - // Name of the token. -}; - - -// 7.. -class ACE_Export ACE_Token_Proxy - // = TITLE - // Abstract representation of ACE tokens. - // - // = DESCRIPTION - // Interface for all Tokens in ACE. This class implements the - // synchronization needed for tokens (condition variables etc.) - // The algorithms for the operations (acquire, release, etc.) - // operate on the generic ACE_Tokens interface. Thus, the _type_ - // of token (mutex, rwlock) can be set at construction of - // ACE_Token_Proxy. You can use all Tokens in ACE through the - // ACE_Token_Proxy by passing the proper values at construction. - // Alternatively, there are class definitions which "know" how to - // do this (ACE_Local_Mutex, ACE_Local_RLock, ACE_Local_WLock). - - // = EXTENDING TOKENS - // To add a new type of token (e.g. semaphore), this class is not - // changed. See ACE_Token_Manager for details. - - // = RESTRICTIONS - // Tokens (e.g. ACE_Mutex_Token) assume that it can always call - // ACE_Token_Proxy::token_acquired () on a new token owner. This - // is not a problem for synchronous use of token proxies (that is, - // when acquires block until successful.) However, for - // implementations of the Token Server, which may use asynch - // operations, the proxy can not go away after an acquire until - // the token is acquired. This is not really a problem, but - // should be understood. -{ -friend class ACE_Token_Manager; -friend class ACE_Token_Invariant_Manager; // For testing. -public: - - // Initialization and termination methods. - ACE_Token_Proxy (void); - // Construction. - - virtual ~ACE_Token_Proxy (void); - // Death. - - virtual int open (const char *name, - int ignore_deadlock = 0, - int debug = 0); - // <name> is the string uniquely identifying the token. - // <ignore_deadlock> can be 1 to disable deadlock notifications. - // <debug> prints debug messages. - - // = The following methods have implementations which are - // independent of the token semantics (mutex, rwlock, etc.) They - // forward operations to the underlying token and perform the - // necessary blocking semantics for operations (condition variables - // etc.) This allows reuse of the blocking code as well as having - // multiple proxies to the same token. - - virtual int acquire (int notify = 0, - void (*sleep_hook)(void *) = 0, - ACE_Synch_Options &options = - ACE_Synch_Options::defaults); - // Calls acquire on the token. Blocks the calling thread if would - // block. - - virtual int renew (int requeue_position = -1, - ACE_Synch_Options &options = - ACE_Synch_Options::defaults); - // Calls renew on the token. Blocks the calling thread if would - // block. - - virtual int tryacquire (void (*sleep_hook)(void *) = 0); - // Calls renew on the token. - - virtual int release (ACE_Synch_Options &options = - ACE_Synch_Options::defaults); - // Calls release on the token. - - virtual int remove (ACE_Synch_Options &options = - ACE_Synch_Options::defaults); - // Calls remove on the token. - - // = Utility methods. - - virtual const char *client_id (void) const; - // Get the client id of the proxy. This is implemented as - // thread-specific data. - - virtual void client_id (const char *client_id); - // Set the client_id for the calling thread. I strongly recommend - // that this not be used unless you really know what you're doing. - // I use this in the Token Server, and it caused many headaches. - - virtual const char *name (void) const; - // Return the name of the token. This is important for use within - // the token servers (local and remote) as well as with token - // collections. So, all derivations of ACE_Token_Proxy must be able to - // stringify some name. The name must uniquely identify a token. - // So, for instance, the token within the reactor should probably be - // called "Reactor Token." - - virtual void sleep_hook (void); - // This should really be called someone_waiting (). - // This is called by ACE_Token_xx's when another proxy enters the - // waiting list and requests that the current token holder be notified. - - virtual void token_acquired (ACE_TPQ_Entry *); - // This is called when a queued (waiting) proxy is removed from the - // waiters list and given the token. - - virtual const char *owner_id (void); - // the client id of the current token holder - - virtual ACE_Token_Proxy *clone (void) const = 0; - // Return a dynamically allocated clone of the derived class. - - void dump (void) const; - // Dump the state of the class. - - virtual int type (void) const; - // This method can be used be Tokens (e.g. Readers/Writer Tokens) to - // distinguish between Proxy types. For instance a Reader proxy - // should return a different type value than a Writer proxy. The - // default implementation returns 0. - -protected: - ACE_Token_Proxy (const ACE_Token_Proxy &); - // Duplication. - - int ignore_deadlock_; - // If this is set, we ignore deadlock. - - int debug_; - // Print a bunch of debug messages. - - ACE_Tokens *token_; - // Reference to the actual logical token. Many ACE_Local_Mutex - // proxies can reference the same ACE_Mutex_Token. - - int handle_options (ACE_Synch_Options &options, - ACE_TOKEN_CONST::COND_VAR &cv); - // Handles cond_var waits. - - ACE_TSS_TPQ_Entry waiter_; - // Waiter info used for asynchronous transactions. - - virtual ACE_Tokens *create_token (const char *name) = 0; - // Make the correct type of ACE_Tokens. This is called by the Token - // Manager. -}; - -// 8.. -class ACE_Export ACE_Null_Token : public ACE_Token_Proxy - // = TITLE - // No op class for nonthreaded platform protocols. -{ -public: - ACE_Null_Token (void) {}; - // Construction. - - virtual int acquire (int /* notify */ = 0, - void (* /* sleep_hook */ )(void *) = 0, - ACE_Synch_Options & /* options */ = - ACE_Synch_Options::defaults) { return 0; } - // Acquire. - - virtual int renew (int /* requeue_position */ = -1, - ACE_Synch_Options & /* options */ = - ACE_Synch_Options::defaults) { return 0; } - // Renew. - - virtual int tryacquire (void (* /* sleep_hook */)(void *) = 0) { return 0; } - // Try acquire. - - virtual int release (ACE_Synch_Options & /* options */ = - ACE_Synch_Options::defaults) { return 0; } - // Release. - - virtual int remove (ACE_Synch_Options & /* options */ = - ACE_Synch_Options::defaults) { return 0; } - // Remove. - - virtual ACE_Token_Proxy *clone (void) const { return new ACE_Null_Token; } - // Return a dynamically allocated clone of the derived class. - - void dump (void) const; - // Dump the state of the class. - - virtual ACE_Tokens *create_token (const char *) { return 0; } - // Do not allow the Token Manager to create us. -}; - -// 9.. -class ACE_Export ACE_Local_Mutex : public ACE_Token_Proxy - // = TITLE - // Class that acquires, renews, and releases a synchronization - // token local to the process. - // - // = DESCRIPTION - // This class is a more general-purpose synchronization mechanism - // than SunOS 5.x mutexes. For example, it implements "recursive - // mutex" semantics, where a thread that owns the token can - // reacquire it without deadlocking. In addition, threads that - // are blocked awaiting the token are serviced in strict FIFO - // order as other threads release the token (SunOS 5.x mutexes - // don't strictly enforce an acquisition order). Lastly, - // ACE_Local_Mutex performs deadlock detection on acquire calls. - // - // = Synchronization operations. - // The interfaces for acquire, tryacquire, renew, release, - // etc. are defined in ACE_Token_Proxy. The semantics for - // ACE_Local_Mutex are that of a mutex. -{ -public: - ACE_Local_Mutex (const char *token_name = 0, - int ignore_deadlock = 0, - int debug = 0); - // <token_name> uniquely id's the token. - // <ignore_deadlock> will allow deadlock to occur (useful for - // testing). <debug> prints a bunch of messages. - - void dump (void) const; - // Dump the state of the class. - - virtual ACE_Token_Proxy *clone (void) const; - // Return deep copy. - -protected: - virtual ACE_Tokens *create_token (const char *name); - // Return a new ACE_Local_Mutex. -}; - -// *. -class ACE_Export ACE_Local_RLock : public ACE_Token_Proxy -// = TITLE -// Class that acquires, renews, and releases a readers lock that -// is local to the process. -// -// = DESCRIPTION -// This class implements the reader interface to canonical -// readers/writer locks. Multiple readers can hold the lock -// simultaneously when no writers have the lock. Alternatively, -// when a writer holds the lock, no other participants (readers or -// writers) may hold the lock. This class is a more -// general-purpose synchronization mechanism than SunOS 5.x RLocks. -// For example, it implements "recursive RLock" semantics, where a -// thread that owns the token can reacquire it without deadlocking. -// In addition, threads that are blocked awaiting the token are -// serviced in strict FIFO order as other threads release the token -// (SunOS 5.x RLockes don't strictly enforce an acquisition -// order). -// -// = Synchronization operations. -// The interfaces for acquire, tryacquire, renew, release, etc. are -// defined in ACE_Token_Proxy. The semantics for ACE_Local_RLock -// are that of a readers/writers lock. Acquire for this class -// implies a reader acquisition. That is, multiple clients may -// acquire a lock for read only. -{ -public: - // = Initialization and termination. - - ACE_Local_RLock (const char *token_name = 0, - int ignore_deadlock = 0, - int debug = 0); - // <token_name> uniquely id's the token. - // <ignore_deadlock> will allow deadlock to occur (useful for - // testing). <debug> prints a bunch of messages. - - void dump (void) const; - // Dump the state of the class. - - virtual int type (void) const; - // Returns ACE_RW_Token::RLOCK. - - virtual ACE_Token_Proxy *clone (void) const; - // Return deep copy. - -protected: - virtual ACE_Tokens *create_token (const char *name); - // Return a new ACE_Local_Mutex. -}; - -// *. -class ACE_Export ACE_Local_WLock : public ACE_Token_Proxy -// = TITLE -// Class that acquires, renews, and releases a writer lock that -// is local to the process. -// -// = DESCRIPTION -// This class implements the writer interface to canonical -// readers/writer locks. Multiple readers can hold the lock -// simultaneously when no writers have the lock. Alternatively, -// when a writer holds the lock, no other participants (readers or -// writers) may hold the lock. This class is a more -// general-purpose synchronization mechanism than SunOS 5.x WLock. -// For example, it implements "recursive WLock" semantics, where a -// thread that owns the token can reacquire it without deadlocking. -// In addition, threads that are blocked awaiting the token are -// serviced in strict FIFO order as other threads release the token -// (SunOS 5.x WLocks don't strictly enforce an acquisition order). -// -// = Synchronization operations. -// The interfaces for acquire, tryacquire, renew, release, -// etc. are defined in ACE_Token_Proxy. The semantics for -// ACE_Local_WLock are that of a readers/writers lock. Acquire -// for this class implies a writer acquisition. That is, only one -// client may hold the lock for writing. -{ -public: - // = Initialization and termination. - - ACE_Local_WLock (const char *token_name = 0, - int ignore_deadlock = 0, - int debug = 0); - // <token_name> uniquely id's the token. - // <ignore_deadlock> will allow deadlock to occur (useful for - // testing). <debug> prints a bunch of messages. - - void dump (void) const; - // Dump the state of the class. - - virtual int type (void) const; - // Returns ACE_RW_Token::WLOCK. - - virtual ACE_Token_Proxy *clone (void) const; - // Return deep copy. - -protected: - ACE_Tokens *create_token (const char *name); - // Return a new ACE_Local_Mutex. -}; - -#if defined (__ACE_INLINE__) -#include "ace/Local_Tokens.i" -#endif /* __ACE_INLINE__ */ -#endif /* ACE_LOCAL_MUTEX_H */ |