base/scoped_native_library.h

   1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef BASE_SCOPED_NATIVE_LIBRARY_H_
   6 #define BASE_SCOPED_NATIVE_LIBRARY_H_
   7
   8 #include "base/base_export.h"
   9 #include "base/native_library.h"
  10
  11 namespace base {
  12
  13 class FilePath;
  14
  15 // A class which encapsulates a base::NativeLibrary object available only in a
  16 // scope.
  17 // This class automatically unloads the loaded library in its destructor.
  18 class BASE_EXPORT ScopedNativeLibrary {
  19  public:
  20   // Initializes with a NULL library.
  21   ScopedNativeLibrary();
  22
  23   // Takes ownership of the given library handle.
  24   explicit ScopedNativeLibrary(NativeLibrary library);
  25
  26   // Opens the given library and manages its lifetime.
  27   explicit ScopedNativeLibrary(const FilePath& library_path);
  28
  29   ~ScopedNativeLibrary();
  30
  31   // Returns true if there's a valid library loaded.
  32   bool is_valid() const { return !!library_; }
  33
  34   void* GetFunctionPointer(const char* function_name) const;
  35
  36   // Takes ownership of the given library handle. Any existing handle will
  37   // be freed.
  38   void Reset(NativeLibrary library);
  39
  40   // Returns the native library handle and removes it from this object. The
  41   // caller must manage the lifetime of the handle.
  42   NativeLibrary Release();
  43
  44  private:
  45   NativeLibrary library_;
  46
  47   DISALLOW_COPY_AND_ASSIGN(ScopedNativeLibrary);
  48 };
  49
  50 }  // namespace base
  51
  52 #endif  // BASE_SCOPED_NATIVE_LIBRARY_H_