base/file_util.cc

   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/file_util.h"
   6
   7 #if defined(OS_WIN)
   8 #include <io.h>
   9 #endif
  10 #include <stdio.h>
  11
  12 #include <fstream>
  13
  14 #include "base/file_path.h"
  15 #include "base/logging.h"
  16 #include "base/string_piece.h"
  17 #include "base/string_util.h"
  18 #include "base/utf_string_conversions.h"
  19
  20 namespace {
  21
  22 const FilePath::CharType kExtensionSeparator = FILE_PATH_LITERAL('.');
  23
  24 }  // namespace
  25
  26 namespace file_util {
  27
  28 bool EndsWithSeparator(const FilePath& path) {
  29   FilePath::StringType value = path.value();
  30   if (value.empty())
  31     return false;
  32
  33   return FilePath::IsSeparator(value[value.size() - 1]);
  34 }
  35
  36 bool EnsureEndsWithSeparator(FilePath* path) {
  37   if (!DirectoryExists(*path))
  38     return false;
  39
  40   if (EndsWithSeparator(*path))
  41     return true;
  42
  43   FilePath::StringType& path_str =
  44       const_cast<FilePath::StringType&>(path->value());
  45   path_str.append(&FilePath::kSeparators[0], 1);
  46
  47   return true;
  48 }
  49
  50 void InsertBeforeExtension(FilePath* path, const FilePath::StringType& suffix) {
  51   FilePath::StringType& value =
  52       const_cast<FilePath::StringType&>(path->value());
  53
  54   const FilePath::StringType::size_type last_dot =
  55       value.rfind(kExtensionSeparator);
  56   const FilePath::StringType::size_type last_separator =
  57       value.find_last_of(FilePath::StringType(FilePath::kSeparators));
  58
  59   if (last_dot == FilePath::StringType::npos ||
  60       (last_separator != std::wstring::npos && last_dot < last_separator)) {
  61     // The path looks something like "C:\pics.old\jojo" or "C:\pics\jojo".
  62     // We should just append the suffix to the entire path.
  63     value.append(suffix);
  64     return;
  65   }
  66
  67   value.insert(last_dot, suffix);
  68 }
  69
  70 bool ContentsEqual(const FilePath& filename1, const FilePath& filename2) {
  71   // We open the file in binary format even if they are text files because
  72   // we are just comparing that bytes are exactly same in both files and not
  73   // doing anything smart with text formatting.
  74   std::ifstream file1(filename1.value().c_str(),
  75                       std::ios::in | std::ios::binary);
  76   std::ifstream file2(filename2.value().c_str(),
  77                       std::ios::in | std::ios::binary);
  78
  79   // Even if both files aren't openable (and thus, in some sense, "equal"),
  80   // any unusable file yields a result of "false".
  81   if (!file1.is_open() || !file2.is_open())
  82     return false;
  83
  84   const int BUFFER_SIZE = 2056;
  85   char buffer1[BUFFER_SIZE], buffer2[BUFFER_SIZE];
  86   do {
  87     file1.read(buffer1, BUFFER_SIZE);
  88     file2.read(buffer2, BUFFER_SIZE);
  89
  90     if ((file1.eof() != file2.eof()) ||
  91         (file1.gcount() != file2.gcount()) ||
  92         (memcmp(buffer1, buffer2, file1.gcount()))) {
  93       file1.close();
  94       file2.close();
  95       return false;
  96     }
  97   } while (!file1.eof() || !file2.eof());
  98
  99   file1.close();
 100   file2.close();
 101   return true;
 102 }
 103
 104 bool TextContentsEqual(const FilePath& filename1, const FilePath& filename2) {
 105   std::ifstream file1(filename1.value().c_str(), std::ios::in);
 106   std::ifstream file2(filename2.value().c_str(), std::ios::in);
 107
 108   // Even if both files aren't openable (and thus, in some sense, "equal"),
 109   // any unusable file yields a result of "false".
 110   if (!file1.is_open() || !file2.is_open())
 111     return false;
 112
 113   do {
 114     std::string line1, line2;
 115     getline(file1, line1);
 116     getline(file2, line2);
 117
 118     // Check for mismatched EOF states, or any error state.
 119     if ((file1.eof() != file2.eof()) ||
 120         file1.bad() || file2.bad()) {
 121       return false;
 122     }
 123
 124     // Trim all '\r' and '\n' characters from the end of the line.
 125     std::string::size_type end1 = line1.find_last_not_of("\r\n");
 126     if (end1 == std::string::npos)
 127       line1.clear();
 128     else if (end1 + 1 < line1.length())
 129       line1.erase(end1 + 1);
 130
 131     std::string::size_type end2 = line2.find_last_not_of("\r\n");
 132     if (end2 == std::string::npos)
 133       line2.clear();
 134     else if (end2 + 1 < line2.length())
 135       line2.erase(end2 + 1);
 136
 137     if (line1 != line2)
 138       return false;
 139   } while (!file1.eof() || !file2.eof());
 140
 141   return true;
 142 }
 143
 144 bool ReadFileToString(const FilePath& path, std::string* contents) {
 145   FILE* file = OpenFile(path, "rb");
 146   if (!file) {
 147     return false;
 148   }
 149
 150   char buf[1 << 16];
 151   size_t len;
 152   while ((len = fread(buf, 1, sizeof(buf), file)) > 0) {
 153     if (contents)
 154       contents->append(buf, len);
 155   }
 156   CloseFile(file);
 157
 158   return true;
 159 }
 160
 161 bool IsDirectoryEmpty(const FilePath& dir_path) {
 162   FileEnumerator files(dir_path, false,
 163       static_cast<FileEnumerator::FileType>(
 164           FileEnumerator::FILES | FileEnumerator::DIRECTORIES));
 165   if (files.Next().value().empty())
 166     return true;
 167   return false;
 168 }
 169
 170 FILE* CreateAndOpenTemporaryFile(FilePath* path) {
 171   FilePath directory;
 172   if (!GetTempDir(&directory))
 173     return NULL;
 174
 175   return CreateAndOpenTemporaryFileInDir(directory, path);
 176 }
 177
 178 bool GetFileSize(const FilePath& file_path, int64* file_size) {
 179   base::PlatformFileInfo info;
 180   if (!GetFileInfo(file_path, &info))
 181     return false;
 182   *file_size = info.size;
 183   return true;
 184 }
 185
 186 bool IsDot(const FilePath& path) {
 187   return FILE_PATH_LITERAL(".") == path.BaseName().value();
 188 }
 189
 190 bool IsDotDot(const FilePath& path) {
 191   return FILE_PATH_LITERAL("..") == path.BaseName().value();
 192 }
 193
 194 bool TouchFile(const FilePath& path,
 195                const base::Time& last_accessed,
 196                const base::Time& last_modified) {
 197   base::PlatformFile file =
 198       base::CreatePlatformFile(path,
 199                                base::PLATFORM_FILE_OPEN |
 200                                base::PLATFORM_FILE_WRITE_ATTRIBUTES,
 201                                NULL, NULL);
 202   if (file != base::kInvalidPlatformFileValue) {
 203     bool result = base::TouchPlatformFile(file, last_accessed, last_modified);
 204     base::ClosePlatformFile(file);
 205     return result;
 206   }
 207
 208   return false;
 209 }
 210
 211 bool SetLastModifiedTime(const FilePath& path,
 212                          const base::Time& last_modified) {
 213   return TouchFile(path, last_modified, last_modified);
 214 }
 215
 216 bool CloseFile(FILE* file) {
 217   if (file == NULL)
 218     return true;
 219   return fclose(file) == 0;
 220 }
 221
 222 bool TruncateFile(FILE* file) {
 223   if (file == NULL)
 224     return false;
 225   long current_offset = ftell(file);
 226   if (current_offset == -1)
 227     return false;
 228 #if defined(OS_WIN)
 229   int fd = _fileno(file);
 230   if (_chsize(fd, current_offset) != 0)
 231     return false;
 232 #else
 233   int fd = fileno(file);
 234   if (ftruncate(fd, current_offset) != 0)
 235     return false;
 236 #endif
 237   return true;
 238 }
 239
 240 bool ContainsPath(const FilePath &parent, const FilePath& child) {
 241   FilePath abs_parent = FilePath(parent);
 242   FilePath abs_child = FilePath(child);
 243
 244   if (!file_util::AbsolutePath(&abs_parent) ||
 245       !file_util::AbsolutePath(&abs_child))
 246     return false;
 247
 248 #if defined(OS_WIN)
 249   // file_util::AbsolutePath() does not flatten case on Windows, so we must do
 250   // a case-insensitive compare.
 251   if (!StartsWith(abs_child.value(), abs_parent.value(), false))
 252 #else
 253   if (!StartsWithASCII(abs_child.value(), abs_parent.value(), true))
 254 #endif
 255     return false;
 256
 257   // file_util::AbsolutePath() normalizes '/' to '\' on Windows, so we only need
 258   // to check kSeparators[0].
 259   if (abs_child.value().length() <= abs_parent.value().length() ||
 260       abs_child.value()[abs_parent.value().length()] !=
 261           FilePath::kSeparators[0])
 262     return false;
 263
 264   return true;
 265 }
 266
 267 int64 ComputeDirectorySize(const FilePath& root_path) {
 268   int64 running_size = 0;
 269   FileEnumerator file_iter(root_path, true, FileEnumerator::FILES);
 270   for (FilePath current = file_iter.Next(); !current.empty();
 271        current = file_iter.Next()) {
 272     FileEnumerator::FindInfo info;
 273     file_iter.GetFindInfo(&info);
 274 #if defined(OS_WIN)
 275     LARGE_INTEGER li = { info.nFileSizeLow, info.nFileSizeHigh };
 276     running_size += li.QuadPart;
 277 #else
 278     running_size += info.stat.st_size;
 279 #endif
 280   }
 281   return running_size;
 282 }
 283
 284 int64 ComputeFilesSize(const FilePath& directory,
 285                        const FilePath::StringType& pattern) {
 286   int64 running_size = 0;
 287   FileEnumerator file_iter(directory, false, FileEnumerator::FILES, pattern);
 288   for (FilePath current = file_iter.Next(); !current.empty();
 289        current = file_iter.Next()) {
 290     FileEnumerator::FindInfo info;
 291     file_iter.GetFindInfo(&info);
 292 #if defined(OS_WIN)
 293     LARGE_INTEGER li = { info.nFileSizeLow, info.nFileSizeHigh };
 294     running_size += li.QuadPart;
 295 #else
 296     running_size += info.stat.st_size;
 297 #endif
 298   }
 299   return running_size;
 300 }
 301
 302 ///////////////////////////////////////////////
 303 // MemoryMappedFile
 304
 305 MemoryMappedFile::~MemoryMappedFile() {
 306   CloseHandles();
 307 }
 308
 309 bool MemoryMappedFile::Initialize(const FilePath& file_name) {
 310   if (IsValid())
 311     return false;
 312
 313   if (!MapFileToMemory(file_name)) {
 314     CloseHandles();
 315     return false;
 316   }
 317
 318   return true;
 319 }
 320
 321 bool MemoryMappedFile::Initialize(base::PlatformFile file) {
 322   if (IsValid())
 323     return false;
 324
 325   file_ = file;
 326
 327   if (!MapFileToMemoryInternal()) {
 328     CloseHandles();
 329     return false;
 330   }
 331
 332   return true;
 333 }
 334
 335 bool MemoryMappedFile::IsValid() const {
 336   return data_ != NULL;
 337 }
 338
 339 bool MemoryMappedFile::MapFileToMemory(const FilePath& file_name) {
 340   file_ = base::CreatePlatformFile(
 341       file_name, base::PLATFORM_FILE_OPEN | base::PLATFORM_FILE_READ,
 342       NULL, NULL);
 343
 344   if (file_ == base::kInvalidPlatformFileValue) {
 345     DLOG(ERROR) << "Couldn't open " << file_name.value();
 346     return false;
 347   }
 348
 349   return MapFileToMemoryInternal();
 350 }
 351
 352 // Deprecated functions ----------------------------------------------------
 353
 354 #if defined(OS_WIN)
 355 void AppendToPath(std::wstring* path, const std::wstring& new_ending) {
 356   if (!path) {
 357     NOTREACHED();
 358     return;  // Don't crash in this function in release builds.
 359   }
 360
 361   if (!EndsWithSeparator(FilePath(*path)))
 362     path->push_back(FilePath::kSeparators[0]);
 363   path->append(new_ending);
 364 }
 365
 366 bool CopyDirectory(const std::wstring& from_path, const std::wstring& to_path,
 367                    bool recursive) {
 368   return CopyDirectory(FilePath::FromWStringHack(from_path),
 369                        FilePath::FromWStringHack(to_path),
 370                        recursive);
 371 }
 372 bool Delete(const std::wstring& path, bool recursive) {
 373   return Delete(FilePath::FromWStringHack(path), recursive);
 374 }
 375 std::wstring GetFileExtensionFromPath(const std::wstring& path) {
 376   std::wstring file_name = FilePath(path).BaseName().value();
 377   const std::wstring::size_type last_dot = file_name.rfind(kExtensionSeparator);
 378   return std::wstring(last_dot == std::wstring::npos ? L""
 379                                                      : file_name, last_dot + 1);
 380 }
 381 FILE* OpenFile(const std::wstring& filename, const char* mode) {
 382   return OpenFile(FilePath::FromWStringHack(filename), mode);
 383 }
 384 int ReadFile(const std::wstring& filename, char* data, int size) {
 385   return ReadFile(FilePath::FromWStringHack(filename), data, size);
 386 }
 387 int WriteFile(const std::wstring& filename, const char* data, int size) {
 388   return WriteFile(FilePath::FromWStringHack(filename), data, size);
 389 }
 390 #endif  // OS_WIN
 391
 392 ///////////////////////////////////////////////
 393 // FileEnumerator
 394 //
 395 // Note: the main logic is in file_util_<platform>.cc
 396
 397 bool FileEnumerator::ShouldSkip(const FilePath& path) {
 398   FilePath::StringType basename = path.BaseName().value();
 399   return IsDot(path) || (IsDotDot(path) && !(INCLUDE_DOT_DOT & file_type_));
 400 }
 401
 402 }  // namespace