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 #include "base/native_library.h"
6
7 #include <windows.h>
8
9 #include "base/file_util.h"
10 #include "base/threading/thread_restrictions.h"
11 #include "base/utf_string_conversions.h"
12
13 namespace base {
14
15 typedef HMODULE (WINAPI* LoadLibraryFunction)(const wchar_t* file_name);
16
LoadNativeLibraryHelper(const FilePath & library_path,LoadLibraryFunction load_library_api)17 NativeLibrary LoadNativeLibraryHelper(const FilePath& library_path,
18 LoadLibraryFunction load_library_api) {
19 // LoadLibrary() opens the file off disk.
20 base::ThreadRestrictions::AssertIOAllowed();
21
22 // Switch the current directory to the library directory as the library
23 // may have dependencies on DLLs in this directory.
24 bool restore_directory = false;
25 FilePath current_directory;
26 if (file_util::GetCurrentDirectory(¤t_directory)) {
27 FilePath plugin_path = library_path.DirName();
28 if (!plugin_path.empty()) {
29 file_util::SetCurrentDirectory(plugin_path);
30 restore_directory = true;
31 }
32 }
33
34 HMODULE module = (*load_library_api)(library_path.value().c_str());
35 if (restore_directory)
36 file_util::SetCurrentDirectory(current_directory);
37
38 return module;
39 }
40
41 // static
LoadNativeLibrary(const FilePath & library_path,std::string * error)42 NativeLibrary LoadNativeLibrary(const FilePath& library_path,
43 std::string* error) {
44 return LoadNativeLibraryHelper(library_path, LoadLibraryW);
45 }
46
LoadNativeLibraryDynamically(const FilePath & library_path)47 NativeLibrary LoadNativeLibraryDynamically(const FilePath& library_path) {
48 typedef HMODULE (WINAPI* LoadLibraryFunction)(const wchar_t* file_name);
49
50 LoadLibraryFunction load_library;
51 load_library = reinterpret_cast<LoadLibraryFunction>(
52 GetProcAddress(GetModuleHandle(L"kernel32.dll"), "LoadLibraryW"));
53
54 return LoadNativeLibraryHelper(library_path, load_library);
55 }
56
57 // static
UnloadNativeLibrary(NativeLibrary library)58 void UnloadNativeLibrary(NativeLibrary library) {
59 FreeLibrary(library);
60 }
61
62 // static
GetFunctionPointerFromNativeLibrary(NativeLibrary library,const char * name)63 void* GetFunctionPointerFromNativeLibrary(NativeLibrary library,
64 const char* name) {
65 return GetProcAddress(library, name);
66 }
67
68 // static
GetNativeLibraryName(const string16 & name)69 string16 GetNativeLibraryName(const string16& name) {
70 return name + ASCIIToUTF16(".dll");
71 }
72
73 } // namespace base
74