| // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| // This file contains utility functions for dealing with the local |
| // filesystem. |
| |
| #ifndef BASE_FILE_UTIL_H_ |
| #define BASE_FILE_UTIL_H_ |
| |
| #include "build/build_config.h" |
| |
| #if defined(OS_WIN) |
| #include <windows.h> |
| #elif defined(OS_POSIX) |
| #include <sys/stat.h> |
| #include <unistd.h> |
| #endif |
| |
| #include <stdio.h> |
| |
| #include <set> |
| #include <string> |
| #include <vector> |
| |
| #include "base/base_export.h" |
| #include "base/basictypes.h" |
| #include "base/files/file_path.h" |
| #include "base/memory/scoped_ptr.h" |
| #include "base/platform_file.h" |
| #include "base/strings/string16.h" |
| |
| #if defined(OS_POSIX) |
| #include "base/file_descriptor_posix.h" |
| #include "base/logging.h" |
| #include "base/posix/eintr_wrapper.h" |
| #endif |
| |
| namespace base { |
| |
| class Time; |
| |
| //----------------------------------------------------------------------------- |
| // Functions that involve filesystem access or modification: |
| |
| // Returns an absolute version of a relative path. Returns an empty path on |
| // error. On POSIX, this function fails if the path does not exist. This |
| // function can result in I/O so it can be slow. |
| BASE_EXPORT FilePath MakeAbsoluteFilePath(const FilePath& input); |
| |
| // Returns the total number of bytes used by all the files under |root_path|. |
| // If the path does not exist the function returns 0. |
| // |
| // This function is implemented using the FileEnumerator class so it is not |
| // particularly speedy in any platform. |
| BASE_EXPORT int64 ComputeDirectorySize(const FilePath& root_path); |
| |
| // Deletes the given path, whether it's a file or a directory. |
| // If it's a directory, it's perfectly happy to delete all of the |
| // directory's contents. Passing true to recursive deletes |
| // subdirectories and their contents as well. |
| // Returns true if successful, false otherwise. It is considered successful |
| // to attempt to delete a file that does not exist. |
| // |
| // In posix environment and if |path| is a symbolic link, this deletes only |
| // the symlink. (even if the symlink points to a non-existent file) |
| // |
| // WARNING: USING THIS WITH recursive==true IS EQUIVALENT |
| // TO "rm -rf", SO USE WITH CAUTION. |
| BASE_EXPORT bool DeleteFile(const FilePath& path, bool recursive); |
| |
| #if defined(OS_WIN) |
| // Schedules to delete the given path, whether it's a file or a directory, until |
| // the operating system is restarted. |
| // Note: |
| // 1) The file/directory to be deleted should exist in a temp folder. |
| // 2) The directory to be deleted must be empty. |
| BASE_EXPORT bool DeleteFileAfterReboot(const FilePath& path); |
| #endif |
| |
| // Moves the given path, whether it's a file or a directory. |
| // If a simple rename is not possible, such as in the case where the paths are |
| // on different volumes, this will attempt to copy and delete. Returns |
| // true for success. |
| // This function fails if either path contains traversal components ('..'). |
| BASE_EXPORT bool Move(const FilePath& from_path, const FilePath& to_path); |
| |
| // Renames file |from_path| to |to_path|. Both paths must be on the same |
| // volume, or the function will fail. Destination file will be created |
| // if it doesn't exist. Prefer this function over Move when dealing with |
| // temporary files. On Windows it preserves attributes of the target file. |
| // Returns true on success, leaving *error unchanged. |
| // Returns false on failure and sets *error appropriately, if it is non-NULL. |
| BASE_EXPORT bool ReplaceFile(const FilePath& from_path, |
| const FilePath& to_path, |
| PlatformFileError* error); |
| |
| // Copies a single file. Use CopyDirectory to copy directories. |
| // This function fails if either path contains traversal components ('..'). |
| BASE_EXPORT bool CopyFile(const FilePath& from_path, const FilePath& to_path); |
| |
| // Copies the given path, and optionally all subdirectories and their contents |
| // as well. |
| // |
| // If there are files existing under to_path, always overwrite. Returns true |
| // if successful, false otherwise. Wildcards on the names are not supported. |
| // |
| // If you only need to copy a file use CopyFile, it's faster. |
| BASE_EXPORT bool CopyDirectory(const FilePath& from_path, |
| const FilePath& to_path, |
| bool recursive); |
| |
| // Returns true if the given path exists on the local filesystem, |
| // false otherwise. |
| BASE_EXPORT bool PathExists(const FilePath& path); |
| |
| // Returns true if the given path is writable by the user, false otherwise. |
| BASE_EXPORT bool PathIsWritable(const FilePath& path); |
| |
| // Returns true if the given path exists and is a directory, false otherwise. |
| BASE_EXPORT bool DirectoryExists(const FilePath& path); |
| |
| // Returns true if the contents of the two files given are equal, false |
| // otherwise. If either file can't be read, returns false. |
| BASE_EXPORT bool ContentsEqual(const FilePath& filename1, |
| const FilePath& filename2); |
| |
| // Returns true if the contents of the two text files given are equal, false |
| // otherwise. This routine treats "\r\n" and "\n" as equivalent. |
| BASE_EXPORT bool TextContentsEqual(const FilePath& filename1, |
| const FilePath& filename2); |
| |
| // Read the file at |path| into |contents|, returning true on success. |
| // This function fails if the |path| contains path traversal components ('..'). |
| // |contents| may be NULL, in which case this function is useful for its |
| // side effect of priming the disk cache. |
| // Useful for unit tests. |
| BASE_EXPORT bool ReadFileToString(const FilePath& path, std::string* contents); |
| |
| #if defined(OS_POSIX) |
| |
| // Read exactly |bytes| bytes from file descriptor |fd|, storing the result |
| // in |buffer|. This function is protected against EINTR and partial reads. |
| // Returns true iff |bytes| bytes have been successfully read from |fd|. |
| BASE_EXPORT bool ReadFromFD(int fd, char* buffer, size_t bytes); |
| |
| // Creates a symbolic link at |symlink| pointing to |target|. Returns |
| // false on failure. |
| BASE_EXPORT bool CreateSymbolicLink(const FilePath& target, |
| const FilePath& symlink); |
| |
| // Reads the given |symlink| and returns where it points to in |target|. |
| // Returns false upon failure. |
| BASE_EXPORT bool ReadSymbolicLink(const FilePath& symlink, FilePath* target); |
| |
| // Bits ans masks of the file permission. |
| enum FilePermissionBits { |
| FILE_PERMISSION_MASK = S_IRWXU | S_IRWXG | S_IRWXO, |
| FILE_PERMISSION_USER_MASK = S_IRWXU, |
| FILE_PERMISSION_GROUP_MASK = S_IRWXG, |
| FILE_PERMISSION_OTHERS_MASK = S_IRWXO, |
| |
| FILE_PERMISSION_READ_BY_USER = S_IRUSR, |
| FILE_PERMISSION_WRITE_BY_USER = S_IWUSR, |
| FILE_PERMISSION_EXECUTE_BY_USER = S_IXUSR, |
| FILE_PERMISSION_READ_BY_GROUP = S_IRGRP, |
| FILE_PERMISSION_WRITE_BY_GROUP = S_IWGRP, |
| FILE_PERMISSION_EXECUTE_BY_GROUP = S_IXGRP, |
| FILE_PERMISSION_READ_BY_OTHERS = S_IROTH, |
| FILE_PERMISSION_WRITE_BY_OTHERS = S_IWOTH, |
| FILE_PERMISSION_EXECUTE_BY_OTHERS = S_IXOTH, |
| }; |
| |
| // Reads the permission of the given |path|, storing the file permission |
| // bits in |mode|. If |path| is symbolic link, |mode| is the permission of |
| // a file which the symlink points to. |
| BASE_EXPORT bool GetPosixFilePermissions(const FilePath& path, int* mode); |
| // Sets the permission of the given |path|. If |path| is symbolic link, sets |
| // the permission of a file which the symlink points to. |
| BASE_EXPORT bool SetPosixFilePermissions(const FilePath& path, int mode); |
| |
| #endif // OS_POSIX |
| |
| // Returns true if the given directory is empty |
| BASE_EXPORT bool IsDirectoryEmpty(const FilePath& dir_path); |
| |
| // Get the temporary directory provided by the system. |
| // |
| // WARNING: In general, you should use CreateTemporaryFile variants below |
| // instead of this function. Those variants will ensure that the proper |
| // permissions are set so that other users on the system can't edit them while |
| // they're open (which can lead to security issues). |
| BASE_EXPORT bool GetTempDir(FilePath* path); |
| |
| // Get a temporary directory for shared memory files. The directory may depend |
| // on whether the destination is intended for executable files, which in turn |
| // depends on how /dev/shmem was mounted. As a result, you must supply whether |
| // you intend to create executable shmem segments so this function can find |
| // an appropriate location. |
| // |
| // Only useful on POSIX; redirects to GetTempDir() on Windows. |
| BASE_EXPORT bool GetShmemTempDir(bool executable, FilePath* path); |
| |
| #if defined(OS_POSIX) |
| // Get the home directory. This is more complicated than just getenv("HOME") |
| // as it knows to fall back on getpwent() etc. |
| // |
| // This function is not currently implemented on Windows or Mac because we |
| // don't use it. Generally you would use one of PathService's APP_DATA |
| // directories on those platforms. If we need it, this could be implemented |
| // there to return the appropriate directory. |
| BASE_EXPORT FilePath GetHomeDir(); |
| #endif // OS_POSIX |
| |
| } // namespace base |
| |
| // ----------------------------------------------------------------------------- |
| |
| namespace file_util { |
| |
| // Creates a temporary file. The full path is placed in |path|, and the |
| // function returns true if was successful in creating the file. The file will |
| // be empty and all handles closed after this function returns. |
| BASE_EXPORT bool CreateTemporaryFile(base::FilePath* path); |
| |
| // Same as CreateTemporaryFile but the file is created in |dir|. |
| BASE_EXPORT bool CreateTemporaryFileInDir(const base::FilePath& dir, |
| base::FilePath* temp_file); |
| |
| // Create and open a temporary file. File is opened for read/write. |
| // The full path is placed in |path|. |
| // Returns a handle to the opened file or NULL if an error occurred. |
| BASE_EXPORT FILE* CreateAndOpenTemporaryFile(base::FilePath* path); |
| // Like above but for shmem files. Only useful for POSIX. |
| // The executable flag says the file needs to support using |
| // mprotect with PROT_EXEC after mapping. |
| BASE_EXPORT FILE* CreateAndOpenTemporaryShmemFile(base::FilePath* path, |
| bool executable); |
| // Similar to CreateAndOpenTemporaryFile, but the file is created in |dir|. |
| BASE_EXPORT FILE* CreateAndOpenTemporaryFileInDir(const base::FilePath& dir, |
| base::FilePath* path); |
| |
| // Create a new directory. If prefix is provided, the new directory name is in |
| // the format of prefixyyyy. |
| // NOTE: prefix is ignored in the POSIX implementation. |
| // If success, return true and output the full path of the directory created. |
| BASE_EXPORT bool CreateNewTempDirectory( |
| const base::FilePath::StringType& prefix, |
| base::FilePath* new_temp_path); |
| |
| // Create a directory within another directory. |
| // Extra characters will be appended to |prefix| to ensure that the |
| // new directory does not have the same name as an existing directory. |
| BASE_EXPORT bool CreateTemporaryDirInDir( |
| const base::FilePath& base_dir, |
| const base::FilePath::StringType& prefix, |
| base::FilePath* new_dir); |
| |
| // Creates a directory, as well as creating any parent directories, if they |
| // don't exist. Returns 'true' on successful creation, or if the directory |
| // already exists. The directory is only readable by the current user. |
| // Returns true on success, leaving *error unchanged. |
| // Returns false on failure and sets *error appropriately, if it is non-NULL. |
| BASE_EXPORT bool CreateDirectoryAndGetError(const base::FilePath& full_path, |
| base::PlatformFileError* error); |
| |
| // Backward-compatible convenience method for the above. |
| BASE_EXPORT bool CreateDirectory(const base::FilePath& full_path); |
| |
| // Returns the file size. Returns true on success. |
| BASE_EXPORT bool GetFileSize(const base::FilePath& file_path, int64* file_size); |
| |
| // Sets |real_path| to |path| with symbolic links and junctions expanded. |
| // On windows, make sure the path starts with a lettered drive. |
| // |path| must reference a file. Function will fail if |path| points to |
| // a directory or to a nonexistent path. On windows, this function will |
| // fail if |path| is a junction or symlink that points to an empty file, |
| // or if |real_path| would be longer than MAX_PATH characters. |
| BASE_EXPORT bool NormalizeFilePath(const base::FilePath& path, |
| base::FilePath* real_path); |
| |
| #if defined(OS_WIN) |
| |
| // Given a path in NT native form ("\Device\HarddiskVolumeXX\..."), |
| // return in |drive_letter_path| the equivalent path that starts with |
| // a drive letter ("C:\..."). Return false if no such path exists. |
| BASE_EXPORT bool DevicePathToDriveLetterPath(const base::FilePath& device_path, |
| base::FilePath* drive_letter_path); |
| |
| // Given an existing file in |path|, set |real_path| to the path |
| // in native NT format, of the form "\Device\HarddiskVolumeXX\..". |
| // Returns false if the path can not be found. Empty files cannot |
| // be resolved with this function. |
| BASE_EXPORT bool NormalizeToNativeFilePath(const base::FilePath& path, |
| base::FilePath* nt_path); |
| #endif |
| |
| // This function will return if the given file is a symlink or not. |
| BASE_EXPORT bool IsLink(const base::FilePath& file_path); |
| |
| // Returns information about the given file path. |
| BASE_EXPORT bool GetFileInfo(const base::FilePath& file_path, |
| base::PlatformFileInfo* info); |
| |
| // Sets the time of the last access and the time of the last modification. |
| BASE_EXPORT bool TouchFile(const base::FilePath& path, |
| const base::Time& last_accessed, |
| const base::Time& last_modified); |
| |
| // Set the time of the last modification. Useful for unit tests. |
| BASE_EXPORT bool SetLastModifiedTime(const base::FilePath& path, |
| const base::Time& last_modified); |
| |
| #if defined(OS_POSIX) |
| // Store inode number of |path| in |inode|. Return true on success. |
| BASE_EXPORT bool GetInode(const base::FilePath& path, ino_t* inode); |
| #endif |
| |
| // Wrapper for fopen-like calls. Returns non-NULL FILE* on success. |
| BASE_EXPORT FILE* OpenFile(const base::FilePath& filename, const char* mode); |
| |
| // Closes file opened by OpenFile. Returns true on success. |
| BASE_EXPORT bool CloseFile(FILE* file); |
| |
| // Truncates an open file to end at the location of the current file pointer. |
| // This is a cross-platform analog to Windows' SetEndOfFile() function. |
| BASE_EXPORT bool TruncateFile(FILE* file); |
| |
| // Reads the given number of bytes from the file into the buffer. Returns |
| // the number of read bytes, or -1 on error. |
| BASE_EXPORT int ReadFile(const base::FilePath& filename, char* data, int size); |
| |
| // Writes the given buffer into the file, overwriting any data that was |
| // previously there. Returns the number of bytes written, or -1 on error. |
| BASE_EXPORT int WriteFile(const base::FilePath& filename, const char* data, |
| int size); |
| #if defined(OS_POSIX) |
| // Append the data to |fd|. Does not close |fd| when done. |
| BASE_EXPORT int WriteFileDescriptor(const int fd, const char* data, int size); |
| #endif |
| // Append the given buffer into the file. Returns the number of bytes written, |
| // or -1 on error. |
| BASE_EXPORT int AppendToFile(const base::FilePath& filename, |
| const char* data, int size); |
| |
| // Gets the current working directory for the process. |
| BASE_EXPORT bool GetCurrentDirectory(base::FilePath* path); |
| |
| // Sets the current working directory for the process. |
| BASE_EXPORT bool SetCurrentDirectory(const base::FilePath& path); |
| |
| // Attempts to find a number that can be appended to the |path| to make it |
| // unique. If |path| does not exist, 0 is returned. If it fails to find such |
| // a number, -1 is returned. If |suffix| is not empty, also checks the |
| // existence of it with the given suffix. |
| BASE_EXPORT int GetUniquePathNumber(const base::FilePath& path, |
| const base::FilePath::StringType& suffix); |
| |
| #if defined(OS_POSIX) |
| // Creates a directory with a guaranteed unique name based on |path|, returning |
| // the pathname if successful, or an empty path if there was an error creating |
| // the directory. Does not create parent directories. |
| BASE_EXPORT base::FilePath MakeUniqueDirectory(const base::FilePath& path); |
| #endif |
| |
| #if defined(OS_POSIX) |
| // Test that |path| can only be changed by a given user and members of |
| // a given set of groups. |
| // Specifically, test that all parts of |path| under (and including) |base|: |
| // * Exist. |
| // * Are owned by a specific user. |
| // * Are not writable by all users. |
| // * Are owned by a member of a given set of groups, or are not writable by |
| // their group. |
| // * Are not symbolic links. |
| // This is useful for checking that a config file is administrator-controlled. |
| // |base| must contain |path|. |
| BASE_EXPORT bool VerifyPathControlledByUser(const base::FilePath& base, |
| const base::FilePath& path, |
| uid_t owner_uid, |
| const std::set<gid_t>& group_gids); |
| #endif // defined(OS_POSIX) |
| |
| #if defined(OS_MACOSX) && !defined(OS_IOS) |
| // Is |path| writable only by a user with administrator privileges? |
| // This function uses Mac OS conventions. The super user is assumed to have |
| // uid 0, and the administrator group is assumed to be named "admin". |
| // Testing that |path|, and every parent directory including the root of |
| // the filesystem, are owned by the superuser, controlled by the group |
| // "admin", are not writable by all users, and contain no symbolic links. |
| // Will return false if |path| does not exist. |
| BASE_EXPORT bool VerifyPathControlledByAdmin(const base::FilePath& path); |
| #endif // defined(OS_MACOSX) && !defined(OS_IOS) |
| |
| // Returns the maximum length of path component on the volume containing |
| // the directory |path|, in the number of FilePath::CharType, or -1 on failure. |
| BASE_EXPORT int GetMaximumPathComponentLength(const base::FilePath& path); |
| |
| // A class to handle auto-closing of FILE*'s. |
| class ScopedFILEClose { |
| public: |
| inline void operator()(FILE* x) const { |
| if (x) { |
| fclose(x); |
| } |
| } |
| }; |
| |
| typedef scoped_ptr_malloc<FILE, ScopedFILEClose> ScopedFILE; |
| |
| #if defined(OS_POSIX) |
| // A class to handle auto-closing of FDs. |
| class ScopedFDClose { |
| public: |
| inline void operator()(int* x) const { |
| if (x && *x >= 0) { |
| if (IGNORE_EINTR(close(*x)) < 0) |
| DPLOG(ERROR) << "close"; |
| } |
| } |
| }; |
| |
| typedef scoped_ptr_malloc<int, ScopedFDClose> ScopedFD; |
| #endif // OS_POSIX |
| |
| #if defined(OS_LINUX) |
| // Broad categories of file systems as returned by statfs() on Linux. |
| enum FileSystemType { |
| FILE_SYSTEM_UNKNOWN, // statfs failed. |
| FILE_SYSTEM_0, // statfs.f_type == 0 means unknown, may indicate AFS. |
| FILE_SYSTEM_ORDINARY, // on-disk filesystem like ext2 |
| FILE_SYSTEM_NFS, |
| FILE_SYSTEM_SMB, |
| FILE_SYSTEM_CODA, |
| FILE_SYSTEM_MEMORY, // in-memory file system |
| FILE_SYSTEM_CGROUP, // cgroup control. |
| FILE_SYSTEM_OTHER, // any other value. |
| FILE_SYSTEM_TYPE_COUNT |
| }; |
| |
| // Attempts determine the FileSystemType for |path|. |
| // Returns false if |path| doesn't exist. |
| BASE_EXPORT bool GetFileSystemType(const base::FilePath& path, |
| FileSystemType* type); |
| #endif |
| |
| } // namespace file_util |
| |
| // Internal -------------------------------------------------------------------- |
| |
| namespace base { |
| namespace internal { |
| |
| // Same as Move but allows paths with traversal components. |
| // Use only with extreme care. |
| BASE_EXPORT bool MoveUnsafe(const FilePath& from_path, |
| const FilePath& to_path); |
| |
| // Same as CopyFile but allows paths with traversal components. |
| // Use only with extreme care. |
| BASE_EXPORT bool CopyFileUnsafe(const FilePath& from_path, |
| const FilePath& to_path); |
| |
| #if defined(OS_WIN) |
| // Copy from_path to to_path recursively and then delete from_path recursively. |
| // Returns true if all operations succeed. |
| // This function simulates Move(), but unlike Move() it works across volumes. |
| // This function is not transactional. |
| BASE_EXPORT bool CopyAndDeleteDirectory(const FilePath& from_path, |
| const FilePath& to_path); |
| #endif // defined(OS_WIN) |
| |
| } // namespace internal |
| } // namespace base |
| |
| #endif // BASE_FILE_UTIL_H_ |