1 files changed, 165 insertions, 0 deletions
diff --git a/include/lldb/Host/ProcessRunLock.h b/include/lldb/Host/ProcessRunLock.h
new file mode 100644
index 0000000..f563be73
--- /dev/null
+++ b/include/lldb/Host/ProcessRunLock.h
@@ -0,0 +1,165 @@
+//===-- ProcessRunLock.h ----------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef liblldb_ProcessRunLock_h_
+#define liblldb_ProcessRunLock_h_
+#if defined(__cplusplus)
+
+#include "lldb/Host/Mutex.h"
+#include "lldb/Host/Condition.h"
+#include <pthread.h>
+#include <stdint.h>
+#include <time.h>
+
+//----------------------------------------------------------------------
+/// Enumerations for broadcasting.
+//----------------------------------------------------------------------
+namespace lldb_private {
+
+//----------------------------------------------------------------------
+/// @class ProcessRunLock ProcessRunLock.h "lldb/Host/ProcessRunLock.h"
+/// @brief A class used to prevent the process from starting while other
+/// threads are accessing its data, and prevent access to its data while
+/// it is running.
+//----------------------------------------------------------------------
+    
+class ProcessRunLock
+{
+public:
+    ProcessRunLock () :
+        m_rwlock(),
+        m_running(false)
+    {
+        int err = ::pthread_rwlock_init(&m_rwlock, NULL); (void)err;
+//#if LLDB_CONFIGURATION_DEBUG
+//        assert(err == 0);
+//#endif
+    }
+
+    ~ProcessRunLock ()
+    {
+        int err = ::pthread_rwlock_destroy (&m_rwlock); (void)err;
+//#if LLDB_CONFIGURATION_DEBUG
+//        assert(err == 0);
+//#endif
+    }
+
+    bool
+    ReadTryLock ()
+    {
+        ::pthread_rwlock_rdlock (&m_rwlock);
+        if (m_running == false)
+        {
+            return true;
+        }
+        ::pthread_rwlock_unlock (&m_rwlock);
+        return false;
+    }
+
+    bool
+    ReadUnlock ()
+    {
+        return ::pthread_rwlock_unlock (&m_rwlock) == 0;
+    }
+    
+    bool
+    SetRunning()
+    {
+        ::pthread_rwlock_wrlock (&m_rwlock);
+        m_running = true;
+        ::pthread_rwlock_unlock (&m_rwlock);
+        return true;
+    }
+    
+    bool
+    TrySetRunning()
+    {
+        bool r;
+
+        if (::pthread_rwlock_trywrlock (&m_rwlock) == 0)
+        {
+            r = !m_running;
+            m_running = true;
+            ::pthread_rwlock_unlock (&m_rwlock);
+            return r;
+        }
+        return false;
+    }
+    
+    bool
+    SetStopped ()
+    {
+        ::pthread_rwlock_wrlock (&m_rwlock);
+        m_running = false;
+        ::pthread_rwlock_unlock (&m_rwlock);
+        return true;
+    }
+
+    class ProcessRunLocker
+    {
+    public:
+        ProcessRunLocker () :
+            m_lock (NULL)
+        {
+        }
+
+        ~ProcessRunLocker()
+        {
+            Unlock();
+        }
+
+        // Try to lock the read lock, but only do so if there are no writers.
+        bool
+        TryLock (ProcessRunLock *lock)
+        {
+            if (m_lock)
+            {
+                if (m_lock == lock)
+                    return true; // We already have this lock locked
+                else
+                    Unlock();
+            }
+            if (lock)
+            {
+                if (lock->ReadTryLock())
+                {
+                    m_lock = lock;
+                    return true;
+                }
+            }
+            return false;
+        }
+
+    protected:
+        void
+        Unlock ()
+        {
+            if (m_lock)
+            {
+                m_lock->ReadUnlock();
+                m_lock = NULL;
+            }
+        }
+        
+        ProcessRunLock *m_lock;
+    private:
+        DISALLOW_COPY_AND_ASSIGN(ProcessRunLocker);
+    };
+
+protected:
+    pthread_rwlock_t m_rwlock;
+    bool m_running;
+private:
+    DISALLOW_COPY_AND_ASSIGN(ProcessRunLock);
+};
+
+} // namespace lldb_private
+
+#endif  // #if defined(__cplusplus)
+#endif // #ifndef liblldb_ProcessRunLock_h_