base/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_NATIVE_LIBRARY_H_
   6 #define BASE_NATIVE_LIBRARY_H_
   7
   8 // This file defines a cross-platform "NativeLibrary" type which represents
   9 // a loadable module.
  10
  11 #include <string>
  12
  13 #include "base/base_export.h"
  14 #include "base/compiler_specific.h"
  15 #include "base/strings/string16.h"
  16 #include "build/build_config.h"
  17
  18 #if defined(OS_WIN)
  19 #include <windows.h>
  20 #elif defined(OS_MACOSX)
  21 #import <CoreFoundation/CoreFoundation.h>
  22 #endif  // OS_*
  23
  24 namespace base {
  25
  26 class FilePath;
  27
  28 #if defined(OS_WIN)
  29 typedef HMODULE NativeLibrary;
  30 #elif defined(OS_MACOSX)
  31 enum NativeLibraryType {
  32   BUNDLE,
  33   DYNAMIC_LIB
  34 };
  35 enum NativeLibraryObjCStatus {
  36   OBJC_UNKNOWN,
  37   OBJC_PRESENT,
  38   OBJC_NOT_PRESENT,
  39 };
  40 struct NativeLibraryStruct {
  41   NativeLibraryType type;
  42   CFBundleRefNum bundle_resource_ref;
  43   NativeLibraryObjCStatus objc_status;
  44   union {
  45     CFBundleRef bundle;
  46     void* dylib;
  47   };
  48 };
  49 typedef NativeLibraryStruct* NativeLibrary;
  50 #elif defined(OS_POSIX)
  51 typedef void* NativeLibrary;
  52 #endif  // OS_*
  53
  54 struct BASE_EXPORT NativeLibraryLoadError {
  55 #if defined(OS_WIN)
  56   NativeLibraryLoadError() : code(0) {}
  57 #endif  // OS_WIN
  58
  59   // Returns a string representation of the load error.
  60   std::string ToString() const;
  61
  62 #if defined(OS_WIN)
  63   DWORD code;
  64 #else
  65   std::string message;
  66 #endif  // OS_WIN
  67 };
  68
  69 // Loads a native library from disk.  Release it with UnloadNativeLibrary when
  70 // you're done.  Returns NULL on failure.
  71 // If |error| is not NULL, it may be filled in on load error.
  72 BASE_EXPORT NativeLibrary LoadNativeLibrary(const FilePath& library_path,
  73                                             NativeLibraryLoadError* error);
  74
  75 #if defined(OS_WIN)
  76 // Loads a native library from disk.  Release it with UnloadNativeLibrary when
  77 // you're done.
  78 // This function retrieves the LoadLibrary function exported from kernel32.dll
  79 // and calls it instead of directly calling the LoadLibrary function via the
  80 // import table.
  81 BASE_EXPORT NativeLibrary LoadNativeLibraryDynamically(
  82     const FilePath& library_path);
  83 #endif  // OS_WIN
  84
  85 // Unloads a native library.
  86 BASE_EXPORT void UnloadNativeLibrary(NativeLibrary library);
  87
  88 // Gets a function pointer from a native library.
  89 BASE_EXPORT void* GetFunctionPointerFromNativeLibrary(NativeLibrary library,
  90                                                       const char* name);
  91
  92 // Returns the full platform specific name for a native library.
  93 // For example:
  94 // "mylib" returns "mylib.dll" on Windows, "libmylib.so" on Linux,
  95 // "mylib.dylib" on Mac.
  96 BASE_EXPORT string16 GetNativeLibraryName(const string16& name);
  97
  98 }  // namespace base
  99
 100 #endif  // BASE_NATIVE_LIBRARY_H_