1 // Copyright 2012 The Chromium Authors
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 "net/base/platform_mime_util.h"
6
7 #include <windows.h>
8
9 #include <string>
10
11 #include "base/strings/utf_string_conversions.h"
12 #include "base/win/registry.h"
13
14 namespace net {
15
GetPlatformMimeTypeFromExtension(const base::FilePath::StringType & ext,std::string * result) const16 bool PlatformMimeUtil::GetPlatformMimeTypeFromExtension(
17 const base::FilePath::StringType& ext, std::string* result) const {
18 // check windows registry for file extension's mime type (registry key
19 // names are not case-sensitive).
20 base::FilePath::StringType value, key = FILE_PATH_LITERAL(".") + ext;
21 base::win::RegKey(HKEY_CLASSES_ROOT, key.c_str(), KEY_READ)
22 .ReadValue(L"Content Type", &value);
23 if (!value.empty()) {
24 *result = base::WideToUTF8(value);
25 return true;
26 }
27 return false;
28 }
29
GetPlatformPreferredExtensionForMimeType(const std::string & mime_type,base::FilePath::StringType * ext) const30 bool PlatformMimeUtil::GetPlatformPreferredExtensionForMimeType(
31 const std::string& mime_type,
32 base::FilePath::StringType* ext) const {
33 base::FilePath::StringType key =
34 L"MIME\\Database\\Content Type\\" + base::UTF8ToWide(mime_type);
35 if (base::win::RegKey(HKEY_CLASSES_ROOT, key.c_str(), KEY_READ)
36 .ReadValue(L"Extension", ext) != ERROR_SUCCESS) {
37 return false;
38 }
39 // Strip off the leading dot, this should always be the case.
40 if (!ext->empty() && ext->front() == '.')
41 ext->erase(ext->begin());
42
43 return true;
44 }
45
GetPlatformExtensionsForMimeType(const std::string & mime_type,std::unordered_set<base::FilePath::StringType> * extensions) const46 void PlatformMimeUtil::GetPlatformExtensionsForMimeType(
47 const std::string& mime_type,
48 std::unordered_set<base::FilePath::StringType>* extensions) const {
49 // Multiple extensions could have the given mime type specified as their types
50 // in their 'HKCR\.<extension>\Content Type' keys. Iterating all the HKCR
51 // entries, though, is wildly impractical. Cheat by returning just the
52 // preferred extension.
53 base::FilePath::StringType ext;
54 if (GetPlatformPreferredExtensionForMimeType(mime_type, &ext))
55 extensions->insert(ext);
56 }
57
58 } // namespace net
59