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 #pragma once
   8
   9 #include "base/base_export.h"
  10 #include "base/native_library.h"
  11
  12 class FilePath;
  13
  14 namespace base {
  15
  16 // A class which encapsulates a base::NativeLibrary object available only in a
  17 // scope.
  18 // This class automatically unloads the loaded library in its destructor.
  19 class BASE_EXPORT ScopedNativeLibrary {
  20  public:
  21   // Initializes with a NULL library.
  22   ScopedNativeLibrary();
  23
  24   // Takes ownership of the given library handle.
  25   explicit ScopedNativeLibrary(NativeLibrary library);
  26
  27   // Opens the given library and manages its lifetime.
  28   explicit ScopedNativeLibrary(const FilePath& library_path);
  29
  30   ~ScopedNativeLibrary();
  31
  32   // Returns true if there's a valid library loaded.
  33   bool is_valid() const { return !!library_; }
  34
  35   void* GetFunctionPointer(const char* function_name) const;
  36
  37   // Takes ownership of the given library handle. Any existing handle will
  38   // be freed.
  39   void Reset(NativeLibrary library);
  40
  41   // Returns the native library handle and removes it from this object. The
  42   // caller must manage the lifetime of the handle.
  43   NativeLibrary Release();
  44
  45  private:
  46   NativeLibrary library_;
  47
  48   DISALLOW_COPY_AND_ASSIGN(ScopedNativeLibrary);
  49 };
  50
  51 }  // namespace base
  52
  53 #endif  // BASE_MEMORY_NATIVE_LIBRARY_H_