| // 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_FILES_FILE_UTIL_H_ |
| #define BASE_FILES_FILE_UTIL_H_ |
| |
| #include <stddef.h> |
| #include <stdint.h> |
| #include <stdio.h> |
| |
| #include <set> |
| #include <string> |
| #include <vector> |
| |
| #if defined(OS_POSIX) || defined(OS_FUCHSIA) |
| #include <sys/stat.h> |
| #include <unistd.h> |
| #endif |
| |
| #include "base/files/file.h" |
| #include "base/files/file_path.h" |
| #include "util/build_config.h" |
| |
| #if defined(OS_WIN) |
| #include <windows.h> |
| #elif defined(OS_POSIX) || defined(OS_FUCHSIA) |
| #include "base/logging.h" |
| #include "base/posix/eintr_wrapper.h" |
| #endif |
| |
| namespace base { |
| |
| class Environment; |
| |
| //----------------------------------------------------------------------------- |
| // 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. |
| 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. |
| int64_t 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. |
| 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. |
| bool DeleteFileAfterReboot(const FilePath& path); |
| #endif |
| |
| // 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. |
| bool ReplaceFile(const FilePath& from_path, |
| const FilePath& to_path, |
| File::Error* error); |
| |
| // Returns true if the given path exists on the local filesystem, |
| // false otherwise. |
| bool PathExists(const FilePath& path); |
| |
| // Returns true if the given path is writable by the user, false otherwise. |
| bool PathIsWritable(const FilePath& path); |
| |
| // Returns true if the given path exists and is a directory, false otherwise. |
| 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. |
| 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. |
| bool TextContentsEqual(const FilePath& filename1, const FilePath& filename2); |
| |
| // Reads the file at |path| into |contents| and returns true on success and |
| // false on error. For security reasons, a |path| containing path traversal |
| // components ('..') is treated as a read error and |contents| is set to empty. |
| // In case of I/O error, |contents| holds the data that could be read from the |
| // file before the error occurred. |
| // |contents| may be NULL, in which case this function is useful for its side |
| // effect of priming the disk cache (could be used for unit tests). |
| bool ReadFileToString(const FilePath& path, std::string* contents); |
| |
| // Reads the file at |path| into |contents| and returns true on success and |
| // false on error. For security reasons, a |path| containing path traversal |
| // components ('..') is treated as a read error and |contents| is set to empty. |
| // In case of I/O error, |contents| holds the data that could be read from the |
| // file before the error occurred. When the file size exceeds |max_size|, the |
| // function returns false with |contents| holding the file truncated to |
| // |max_size|. |
| // |contents| may be NULL, in which case this function is useful for its side |
| // effect of priming the disk cache (could be used for unit tests). |
| bool ReadFileToStringWithMaxSize(const FilePath& path, |
| std::string* contents, |
| size_t max_size); |
| |
| #if defined(OS_POSIX) |
| |
| // Creates a symbolic link at |symlink| pointing to |target|. Returns |
| // false on failure. |
| bool CreateSymbolicLink(const FilePath& target, const FilePath& symlink); |
| |
| // Reads the given |symlink| and returns where it points to in |target|. |
| // Returns false upon failure. |
| bool ReadSymbolicLink(const FilePath& symlink, FilePath* target); |
| |
| // Bits and 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. |
| 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. |
| bool SetPosixFilePermissions(const FilePath& path, int mode); |
| |
| // Returns true iff |executable| can be found in any directory specified by the |
| // environment variable in |env|. |
| bool ExecutableExistsInPath(Environment* env, |
| const FilePath::StringType& executable); |
| |
| #endif // OS_POSIX |
| |
| // Returns true if the given directory is empty |
| bool IsDirectoryEmpty(const FilePath& dir_path); |
| |
| // Get the temporary directory provided by the system. |
| bool GetTempDir(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. |
| bool CreateNewTempDirectory(const FilePath::StringType& prefix, |
| 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. |
| bool CreateTemporaryDirInDir(const FilePath& base_dir, |
| const FilePath::StringType& prefix, |
| 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. |
| bool CreateDirectoryAndGetError(const FilePath& full_path, File::Error* error); |
| |
| // Backward-compatible convenience method for the above. |
| bool CreateDirectory(const FilePath& full_path); |
| |
| // Returns the file size. Returns true on success. |
| bool GetFileSize(const FilePath& file_path, int64_t* 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. |
| bool NormalizeFilePath(const FilePath& path, 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. |
| bool DevicePathToDriveLetterPath(const FilePath& device_path, |
| 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. |
| bool NormalizeToNativeFilePath(const FilePath& path, FilePath* nt_path); |
| #endif |
| |
| // This function will return if the given file is a symlink or not. |
| bool IsLink(const FilePath& file_path); |
| |
| // Returns information about the given file path. |
| bool GetFileInfo(const FilePath& file_path, File::Info* info); |
| |
| // Wrapper for fopen-like calls. Returns non-NULL FILE* on success. The |
| // underlying file descriptor (POSIX) or handle (Windows) is unconditionally |
| // configured to not be propagated to child processes. |
| FILE* OpenFile(const FilePath& filename, const char* mode); |
| |
| // Closes file opened by OpenFile. Returns true on success. |
| bool CloseFile(FILE* file); |
| |
| // Associates a standard FILE stream with an existing File. Note that this |
| // functions take ownership of the existing File. |
| FILE* FileToFILE(File file, const char* mode); |
| |
| // Truncates an open file to end at the location of the current file pointer. |
| // This is a cross-platform analog to Windows' SetEndOfFile() function. |
| bool TruncateFile(FILE* file); |
| |
| // Reads at most the given number of bytes from the file into the buffer. |
| // Returns the number of read bytes, or -1 on error. |
| int ReadFile(const FilePath& filename, char* data, int max_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. |
| int WriteFile(const FilePath& filename, const char* data, int size); |
| |
| #if defined(OS_POSIX) || defined(OS_FUCHSIA) |
| // Appends |data| to |fd|. Does not close |fd| when done. Returns true iff |
| // |size| bytes of |data| were written to |fd|. |
| bool WriteFileDescriptor(const int fd, const char* data, int size); |
| #endif |
| |
| // Appends |data| to |filename|. Returns true iff |size| bytes of |data| were |
| // written to |filename|. |
| bool AppendToFile(const FilePath& filename, const char* data, int size); |
| |
| // Gets the current working directory for the process. |
| bool GetCurrentDirectory(FilePath* path); |
| |
| // Sets the current working directory for the process. |
| bool SetCurrentDirectory(const 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. |
| int GetUniquePathNumber(const FilePath& path, |
| const FilePath::StringType& suffix); |
| |
| // Sets the given |fd| to non-blocking mode. |
| // Returns true if it was able to set it in the non-blocking mode, otherwise |
| // false. |
| bool SetNonBlocking(int fd); |
| |
| #if defined(OS_POSIX) || defined(OS_FUCHSIA) |
| // Creates a non-blocking, close-on-exec pipe. |
| // This creates a non-blocking pipe that is not intended to be shared with any |
| // child process. This will be done atomically if the operating system supports |
| // it. Returns true if it was able to create the pipe, otherwise false. |
| bool CreateLocalNonBlockingPipe(int fds[2]); |
| |
| // Sets the given |fd| to close-on-exec mode. |
| // Returns true if it was able to set it in the close-on-exec mode, otherwise |
| // false. |
| bool SetCloseOnExec(int fd); |
| |
| // 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|. |
| 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) || defined(OS_FUCHSIA) |
| |
| #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. |
| 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. |
| int GetMaximumPathComponentLength(const base::FilePath& path); |
| |
| #if defined(OS_LINUX) || defined(OS_AIX) || defined(OS_BSD) |
| // 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. |
| bool GetFileSystemType(const FilePath& path, FileSystemType* type); |
| #endif |
| |
| } // namespace base |
| |
| #endif // BASE_FILES_FILE_UTIL_H_ |