1 // Copyright 2013 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 "base/files/file_enumerator.h"
6
7 #include <stdint.h>
8 #include <string.h>
9
10 #include "base/check.h"
11 #include "base/check_op.h"
12 #include "base/notreached.h"
13 #include "base/strings/string_util.h"
14 #include "base/threading/scoped_blocking_call.h"
15 #include "base/win/shlwapi.h"
16
17 namespace base {
18
19 namespace {
20
BuildSearchFilter(FileEnumerator::FolderSearchPolicy policy,const FilePath & root_path,const FilePath::StringType & pattern)21 FilePath BuildSearchFilter(FileEnumerator::FolderSearchPolicy policy,
22 const FilePath& root_path,
23 const FilePath::StringType& pattern) {
24 // MATCH_ONLY policy filters incoming files by pattern on OS side. ALL policy
25 // collects all files and filters them manually.
26 switch (policy) {
27 case FileEnumerator::FolderSearchPolicy::MATCH_ONLY:
28 return root_path.Append(pattern);
29 case FileEnumerator::FolderSearchPolicy::ALL:
30 return root_path.Append(FILE_PATH_LITERAL("*"));
31 }
32 NOTREACHED();
33 }
34
35 } // namespace
36
37 // FileEnumerator::FileInfo ----------------------------------------------------
38
FileInfo()39 FileEnumerator::FileInfo::FileInfo() {
40 memset(&find_data_, 0, sizeof(find_data_));
41 }
42
IsDirectory() const43 bool FileEnumerator::FileInfo::IsDirectory() const {
44 return (find_data().dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) != 0;
45 }
46
GetName() const47 FilePath FileEnumerator::FileInfo::GetName() const {
48 return FilePath(find_data().cFileName);
49 }
50
GetSize() const51 int64_t FileEnumerator::FileInfo::GetSize() const {
52 ULARGE_INTEGER size;
53 size.HighPart = find_data().nFileSizeHigh;
54 size.LowPart = find_data().nFileSizeLow;
55 DCHECK_LE(size.QuadPart,
56 static_cast<ULONGLONG>(std::numeric_limits<int64_t>::max()));
57 return static_cast<int64_t>(size.QuadPart);
58 }
59
GetLastModifiedTime() const60 Time FileEnumerator::FileInfo::GetLastModifiedTime() const {
61 return Time::FromFileTime(find_data().ftLastWriteTime);
62 }
63
64 // FileEnumerator --------------------------------------------------------------
65
FileEnumerator(const FilePath & root_path,bool recursive,int file_type)66 FileEnumerator::FileEnumerator(const FilePath& root_path,
67 bool recursive,
68 int file_type)
69 : FileEnumerator(root_path,
70 recursive,
71 file_type,
72 FilePath::StringType(),
73 FolderSearchPolicy::MATCH_ONLY) {}
74
FileEnumerator(const FilePath & root_path,bool recursive,int file_type,const FilePath::StringType & pattern)75 FileEnumerator::FileEnumerator(const FilePath& root_path,
76 bool recursive,
77 int file_type,
78 const FilePath::StringType& pattern)
79 : FileEnumerator(root_path,
80 recursive,
81 file_type,
82 pattern,
83 FolderSearchPolicy::MATCH_ONLY) {}
84
FileEnumerator(const FilePath & root_path,bool recursive,int file_type,const FilePath::StringType & pattern,FolderSearchPolicy folder_search_policy)85 FileEnumerator::FileEnumerator(const FilePath& root_path,
86 bool recursive,
87 int file_type,
88 const FilePath::StringType& pattern,
89 FolderSearchPolicy folder_search_policy)
90 : FileEnumerator(root_path,
91 recursive,
92 file_type,
93 pattern,
94 folder_search_policy,
95 ErrorPolicy::IGNORE_ERRORS) {}
96
FileEnumerator(const FilePath & root_path,bool recursive,int file_type,const FilePath::StringType & pattern,FolderSearchPolicy folder_search_policy,ErrorPolicy error_policy)97 FileEnumerator::FileEnumerator(const FilePath& root_path,
98 bool recursive,
99 int file_type,
100 const FilePath::StringType& pattern,
101 FolderSearchPolicy folder_search_policy,
102 ErrorPolicy error_policy)
103 : recursive_(recursive),
104 file_type_(file_type),
105 pattern_(!pattern.empty() ? pattern : FILE_PATH_LITERAL("*")),
106 folder_search_policy_(folder_search_policy),
107 error_policy_(error_policy) {
108 // INCLUDE_DOT_DOT must not be specified if recursive.
109 DCHECK(!(recursive && (INCLUDE_DOT_DOT & file_type_)));
110
111 if (file_type_ & FileType::NAMES_ONLY) {
112 DCHECK(!recursive_);
113 DCHECK_EQ(file_type_ & ~(FileType::NAMES_ONLY | FileType::INCLUDE_DOT_DOT),
114 0);
115 file_type_ |= (FileType::FILES | FileType::DIRECTORIES);
116 }
117
118 memset(&find_data_, 0, sizeof(find_data_));
119 pending_paths_.push(root_path);
120 }
121
~FileEnumerator()122 FileEnumerator::~FileEnumerator() {
123 if (find_handle_ != INVALID_HANDLE_VALUE)
124 FindClose(find_handle_);
125 }
126
GetInfo() const127 FileEnumerator::FileInfo FileEnumerator::GetInfo() const {
128 DCHECK(!(file_type_ & FileType::NAMES_ONLY));
129 CHECK(has_find_data_);
130 FileInfo ret;
131 memcpy(&ret.find_data_, &find_data_, sizeof(find_data_));
132 return ret;
133 }
134
Next()135 FilePath FileEnumerator::Next() {
136 ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
137
138 while (has_find_data_ || !pending_paths_.empty()) {
139 if (!has_find_data_) {
140 // The last find FindFirstFile operation is done, prepare a new one.
141 root_path_ = pending_paths_.top();
142 pending_paths_.pop();
143
144 // Start a new find operation.
145 const FilePath src =
146 BuildSearchFilter(folder_search_policy_, root_path_, pattern_);
147 find_handle_ = FindFirstFileEx(src.value().c_str(),
148 FindExInfoBasic, // Omit short name.
149 ChromeToWindowsType(&find_data_),
150 FindExSearchNameMatch, nullptr,
151 FIND_FIRST_EX_LARGE_FETCH);
152 has_find_data_ = true;
153 } else {
154 // Search for the next file/directory.
155 if (!FindNextFile(find_handle_, ChromeToWindowsType(&find_data_))) {
156 FindClose(find_handle_);
157 find_handle_ = INVALID_HANDLE_VALUE;
158 }
159 }
160
161 DWORD last_error = GetLastError();
162 if (INVALID_HANDLE_VALUE == find_handle_) {
163 has_find_data_ = false;
164
165 // MATCH_ONLY policy clears pattern for matched subfolders. ALL policy
166 // applies pattern for all subfolders.
167 if (folder_search_policy_ == FolderSearchPolicy::MATCH_ONLY) {
168 // This is reached when we have finished a directory and are advancing
169 // to the next one in the queue. We applied the pattern (if any) to the
170 // files in the root search directory, but for those directories which
171 // were matched, we want to enumerate all files inside them. This will
172 // happen when the handle is empty.
173 pattern_ = FILE_PATH_LITERAL("*");
174 }
175
176 if (last_error == ERROR_NO_MORE_FILES ||
177 error_policy_ == ErrorPolicy::IGNORE_ERRORS) {
178 continue;
179 }
180
181 error_ = File::OSErrorToFileError(last_error);
182 return FilePath();
183 }
184
185 const FilePath filename(find_data().cFileName);
186 if (ShouldSkip(filename))
187 continue;
188
189 const bool is_dir =
190 (find_data().dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) != 0;
191 const FilePath abs_path = root_path_.Append(filename);
192
193 // Check if directory should be processed recursive.
194 if (is_dir && recursive_) {
195 // If |cur_file| is a directory, and we are doing recursive searching,
196 // add it to pending_paths_ so we scan it after we finish scanning this
197 // directory. However, don't do recursion through reparse points or we
198 // may end up with an infinite cycle.
199 DWORD attributes = GetFileAttributes(abs_path.value().c_str());
200 if (!(attributes & FILE_ATTRIBUTE_REPARSE_POINT))
201 pending_paths_.push(abs_path);
202 }
203
204 if (IsTypeMatched(is_dir) && IsPatternMatched(filename))
205 return abs_path;
206 }
207 return FilePath();
208 }
209
IsPatternMatched(const FilePath & src) const210 bool FileEnumerator::IsPatternMatched(const FilePath& src) const {
211 switch (folder_search_policy_) {
212 case FolderSearchPolicy::MATCH_ONLY:
213 // MATCH_ONLY policy filters by pattern on search request, so all found
214 // files already fits to pattern.
215 return true;
216 case FolderSearchPolicy::ALL:
217 // ALL policy enumerates all files, we need to check pattern match
218 // manually.
219 return PathMatchSpec(src.value().c_str(), pattern_.c_str()) == TRUE;
220 }
221 NOTREACHED();
222 }
223
224 } // namespace base
225