// gold-threads.h -- thread support for gold -*- C++ -*-
-// Copyright 2006, 2007 Free Software Foundation, Inc.
+// Copyright 2006, 2007, 2008 Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.
// This file is part of gold.
{
class Condvar;
+class Initialize_lock_once;
// The interface for the implementation of a Lock.
Lock& lock_;
};
+class Hold_optional_lock
+{
+ public:
+ Hold_optional_lock(Lock* lock)
+ : lock_(lock)
+ {
+ if (this->lock_ != NULL)
+ this->lock_->acquire();
+ }
+
+ ~Hold_optional_lock()
+ {
+ if (this->lock_ != NULL)
+ this->lock_->release();
+ }
+
+ private:
+ Hold_optional_lock(const Hold_optional_lock&);
+ Hold_optional_lock& operator=(const Hold_optional_lock&);
+
+ Lock* lock_;
+};
+
// The interface for the implementation of a condition variable.
class Condvar_impl
Condvar_impl* condvar_;
};
+// A class used to initialize a lock exactly once, after the options
+// have been read. This is needed because the implementation of locks
+// depends on whether we've seen the --threads option. Before the
+// options have been read, we know we are single-threaded, so we can
+// get by without using a lock. This class should be an instance
+// variable of the class which has a lock which needs to be
+// initialized.
+
+class Initialize_lock
+{
+ public:
+ // The class which uses this will have a pointer to a lock. This
+ // must be constructed with a pointer to that pointer.
+ Initialize_lock(Lock** pplock);
+
+ // Initialize the lock. Return true if the lock is now initialized,
+ // false if it is not (because the options have not yet been read).
+ bool
+ initialize();
+
+ private:
+ // A pointer to the lock pointer which must be initialized.
+ Lock** const pplock_;
+ // If needed, a pointer to a pthread_once_t structure.
+ Initialize_lock_once* once_;
+};
+
} // End namespace gold.
#endif // !defined(GOLD_THREADS_H)