test_file_util_win.cc revision dc0f95d653279beabeb9817299e2902918ba123e 
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/test/test_file_util.h"
6
7#include <shlwapi.h>
8#include <windows.h>
9
10#include <vector>
11
12#include "base/file_path.h"
13#include "base/file_util.h"
14#include "base/logging.h"
15#include "base/win/scoped_handle.h"
16#include "base/threading/platform_thread.h"
17
18namespace file_util {
19
20static const ptrdiff_t kOneMB = 1024 * 1024;
21
22bool DieFileDie(const FilePath& file, bool recurse) {
23  // It turns out that to not induce flakiness a long timeout is needed.
24  const int kTimeoutMs = 10000;
25
26  if (!file_util::PathExists(file))
27    return true;
28
29  // Sometimes Delete fails, so try a few more times. Divide the timeout
30  // into short chunks, so that if a try succeeds, we won't delay the test
31  // for too long.
32  for (int i = 0; i < 25; ++i) {
33    if (file_util::Delete(file, recurse))
34      return true;
35    base::PlatformThread::Sleep(kTimeoutMs / 25);
36  }
37  return false;
38}
39
40bool EvictFileFromSystemCache(const FilePath& file) {
41  // Request exclusive access to the file and overwrite it with no buffering.
42  base::win::ScopedHandle file_handle(
43      CreateFile(file.value().c_str(), GENERIC_READ | GENERIC_WRITE, 0, NULL,
44                 OPEN_EXISTING, FILE_FLAG_NO_BUFFERING, NULL));
45  if (!file_handle)
46    return false;
47
48  // Get some attributes to restore later.
49  BY_HANDLE_FILE_INFORMATION bhi = {0};
50  CHECK(::GetFileInformationByHandle(file_handle, &bhi));
51
52  // Execute in chunks. It could be optimized. We want to do few of these since
53  // these operations will be slow without the cache.
54
55  // Allocate a buffer for the reads and the writes.
56  char* buffer = reinterpret_cast<char*>(VirtualAlloc(NULL,
57                                                      kOneMB,
58                                                      MEM_COMMIT | MEM_RESERVE,
59                                                      PAGE_READWRITE));
60
61  // If the file size isn't a multiple of kOneMB, we'll need special
62  // processing.
63  bool file_is_aligned = true;
64  int total_bytes = 0;
65  DWORD bytes_read, bytes_written;
66  for (;;) {
67    bytes_read = 0;
68    ::ReadFile(file_handle, buffer, kOneMB, &bytes_read, NULL);
69    if (bytes_read == 0)
70      break;
71
72    if (bytes_read < kOneMB) {
73      // Zero out the remaining part of the buffer.
74      // WriteFile will fail if we provide a buffer size that isn't a
75      // sector multiple, so we'll have to write the entire buffer with
76      // padded zeros and then use SetEndOfFile to truncate the file.
77      ZeroMemory(buffer + bytes_read, kOneMB - bytes_read);
78      file_is_aligned = false;
79    }
80
81    // Move back to the position we just read from.
82    // Note that SetFilePointer will also fail if total_bytes isn't sector
83    // aligned, but that shouldn't happen here.
84    DCHECK((total_bytes % kOneMB) == 0);
85    SetFilePointer(file_handle, total_bytes, NULL, FILE_BEGIN);
86    if (!::WriteFile(file_handle, buffer, kOneMB, &bytes_written, NULL) ||
87        bytes_written != kOneMB) {
88      BOOL freed = VirtualFree(buffer, 0, MEM_RELEASE);
89      DCHECK(freed);
90      NOTREACHED();
91      return false;
92    }
93
94    total_bytes += bytes_read;
95
96    // If this is false, then we just processed the last portion of the file.
97    if (!file_is_aligned)
98      break;
99  }
100
101  BOOL freed = VirtualFree(buffer, 0, MEM_RELEASE);
102  DCHECK(freed);
103
104  if (!file_is_aligned) {
105    // The size of the file isn't a multiple of 1 MB, so we'll have
106    // to open the file again, this time without the FILE_FLAG_NO_BUFFERING
107    // flag and use SetEndOfFile to mark EOF.
108    file_handle.Set(NULL);
109    file_handle.Set(CreateFile(file.value().c_str(), GENERIC_WRITE, 0, NULL,
110                               OPEN_EXISTING, 0, NULL));
111    CHECK_NE(SetFilePointer(file_handle, total_bytes, NULL, FILE_BEGIN),
112             INVALID_SET_FILE_POINTER);
113    CHECK(::SetEndOfFile(file_handle));
114  }
115
116  // Restore the file attributes.
117  CHECK(::SetFileTime(file_handle, &bhi.ftCreationTime, &bhi.ftLastAccessTime,
118                      &bhi.ftLastWriteTime));
119
120  return true;
121}
122
123// Like CopyFileNoCache but recursively copies all files and subdirectories
124// in the given input directory to the output directory.
125bool CopyRecursiveDirNoCache(const FilePath& source_dir,
126                             const FilePath& dest_dir) {
127  // Try to create the directory if it doesn't already exist.
128  if (!CreateDirectory(dest_dir)) {
129    if (GetLastError() != ERROR_ALREADY_EXISTS)
130      return false;
131  }
132
133  std::vector<std::wstring> files_copied;
134
135  std::wstring src(source_dir.value());
136  file_util::AppendToPath(&src, L"*");
137
138  WIN32_FIND_DATA fd;
139  HANDLE fh = FindFirstFile(src.c_str(), &fd);
140  if (fh == INVALID_HANDLE_VALUE)
141    return false;
142
143  do {
144    std::wstring cur_file(fd.cFileName);
145    if (cur_file == L"." || cur_file == L"..")
146      continue;  // Skip these special entries.
147
148    FilePath cur_source_path = source_dir.Append(cur_file);
149    FilePath cur_dest_path = dest_dir.Append(cur_file);
150
151    if (fd.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) {
152      // Recursively copy a subdirectory. We stripped "." and ".." already.
153      if (!CopyRecursiveDirNoCache(cur_source_path, cur_dest_path)) {
154        FindClose(fh);
155        return false;
156      }
157    } else {
158      // Copy the file.
159      if (!::CopyFile(cur_source_path.value().c_str(),
160                      cur_dest_path.value().c_str(), false)) {
161        FindClose(fh);
162        return false;
163      }
164
165      // We don't check for errors from this function, often, we are copying
166      // files that are in the repository, and they will have read-only set.
167      // This will prevent us from evicting from the cache, but these don't
168      // matter anyway.
169      EvictFileFromSystemCache(cur_dest_path);
170    }
171  } while (FindNextFile(fh, &fd));
172
173  FindClose(fh);
174  return true;
175}
176
177// Checks if the volume supports Alternate Data Streams. This is required for
178// the Zone Identifier implementation.
179bool VolumeSupportsADS(const FilePath& path) {
180  wchar_t drive[MAX_PATH] = {0};
181  wcscpy_s(drive, MAX_PATH, path.value().c_str());
182
183  if (!PathStripToRootW(drive))
184    return false;
185
186  DWORD fs_flags = 0;
187  if (!GetVolumeInformationW(drive, NULL, 0, 0, NULL, &fs_flags, NULL, 0))
188    return false;
189
190  if (fs_flags & FILE_NAMED_STREAMS)
191    return true;
192
193  return false;
194}
195
196// Return whether the ZoneIdentifier is correctly set to "Internet" (3)
197// Only returns a valid result when called from same process as the
198// one that (was supposed to have) set the zone identifier.
199bool HasInternetZoneIdentifier(const FilePath& full_path) {
200  FilePath zone_path(full_path.value() + L":Zone.Identifier");
201  std::string zone_path_contents;
202  if (!file_util::ReadFileToString(zone_path, &zone_path_contents))
203    return false;
204
205  static const char kInternetIdentifier[] = "[ZoneTransfer]\nZoneId=3";
206  static const size_t kInternetIdentifierSize =
207      // Don't include null byte in size of identifier.
208      arraysize(kInternetIdentifier) - 1;
209
210  // Our test is that the initial characters match the above, and that
211  // the character after the end of the string is eof, null, or newline; any
212  // of those three will invoke the Window Finder cautionary dialog.
213  return ((zone_path_contents.compare(0, kInternetIdentifierSize,
214                                      kInternetIdentifier) == 0) &&
215          (kInternetIdentifierSize == zone_path_contents.length() ||
216           zone_path_contents[kInternetIdentifierSize] == '\0' ||
217           zone_path_contents[kInternetIdentifierSize] == '\n'));
218}
219
220std::wstring FilePathAsWString(const FilePath& path) {
221  return path.value();
222}
223
224}  // namespace file_util
225