1 files changed, 73 insertions, 0 deletions
diff --git a/include/lldb/Host/LockFileBase.h b/include/lldb/Host/LockFileBase.h
new file mode 100644
index 000000000000..35dd7d817c59
--- /dev/null
+++ b/include/lldb/Host/LockFileBase.h
@@ -0,0 +1,73 @@
+//===-- LockFileBase.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_Host_LockFileBase_h_
+#define liblldb_Host_LockFileBase_h_
+
+#include "lldb/Core/Error.h"
+
+#include <functional>
+
+namespace lldb_private
+{
+
+class LockFileBase
+{
+public:
+    virtual ~LockFileBase () = default;
+
+    bool
+    IsLocked () const;
+
+    Error
+    WriteLock (const uint64_t start, const uint64_t len);
+    Error
+    TryWriteLock (const uint64_t start, const uint64_t len);
+
+    Error
+    ReadLock (const uint64_t start, const uint64_t len);
+    Error
+    TryReadLock (const uint64_t start, const uint64_t len);
+
+    Error
+    Unlock ();
+
+protected:
+    using Locker = std::function<Error (const uint64_t, const uint64_t)>;
+
+    LockFileBase (int fd);
+
+    virtual bool
+    IsValidFile () const;
+
+    virtual Error
+    DoWriteLock (const uint64_t start, const uint64_t len) = 0;
+    virtual Error
+    DoTryWriteLock (const uint64_t start, const uint64_t len) = 0;
+
+    virtual Error
+    DoReadLock (const uint64_t start, const uint64_t len) = 0;
+    virtual Error
+    DoTryReadLock (const uint64_t start, const uint64_t len) = 0;
+
+    virtual Error
+    DoUnlock () = 0;
+
+    Error
+    DoLock (const Locker &locker, const uint64_t start, const uint64_t len);
+
+    int m_fd;  // not owned.
+    bool m_locked;
+    uint64_t m_start;
+    uint64_t m_len;
+};
+
+}
+
+#endif