blob: 4d031cb7a52e4c69253e4239cda3a78e9232e1cc [file] [log] [blame]
// ignore-tidy-filelength
//! Filesystem manipulation operations.
//!
//! This module contains basic methods to manipulate the contents of the local
//! filesystem. All methods in this module represent cross-platform filesystem
//! operations. Extra platform-specific functionality can be found in the
//! extension traits of `std::os::$platform`.
#![stable(feature = "rust1", since = "1.0.0")]
#![deny(unsafe_op_in_unsafe_fn)]
use crate::ffi::OsString;
use crate::fmt;
use crate::io::{self, Initializer, IoSlice, IoSliceMut, Read, Seek, SeekFrom, Write};
use crate::path::{Path, PathBuf};
use crate::sys::fs as fs_imp;
use crate::sys_common::{AsInner, AsInnerMut, FromInner, IntoInner};
use crate::time::SystemTime;
/// A reference to an open file on the filesystem.
///
/// An instance of a `File` can be read and/or written depending on what options
/// it was opened with. Files also implement [`Seek`] to alter the logical cursor
/// that the file contains internally.
///
/// Files are automatically closed when they go out of scope. Errors detected
/// on closing are ignored by the implementation of `Drop`. Use the method
/// [`sync_all`] if these errors must be manually handled.
///
/// # Examples
///
/// Creates a new file and write bytes to it (you can also use [`write`]):
///
/// ```no_run
/// use std::fs::File;
/// use std::io::prelude::*;
///
/// fn main() -> std::io::Result<()> {
/// let mut file = File::create("foo.txt")?;
/// file.write_all(b"Hello, world!")?;
/// Ok(())
/// }
/// ```
///
/// Read the contents of a file into a [`String`] (you can also use [`read`]):
///
/// ```no_run
/// use std::fs::File;
/// use std::io::prelude::*;
///
/// fn main() -> std::io::Result<()> {
/// let mut file = File::open("foo.txt")?;
/// let mut contents = String::new();
/// file.read_to_string(&mut contents)?;
/// assert_eq!(contents, "Hello, world!");
/// Ok(())
/// }
/// ```
///
/// It can be more efficient to read the contents of a file with a buffered
/// [`Read`]er. This can be accomplished with [`BufReader<R>`]:
///
/// ```no_run
/// use std::fs::File;
/// use std::io::BufReader;
/// use std::io::prelude::*;
///
/// fn main() -> std::io::Result<()> {
/// let file = File::open("foo.txt")?;
/// let mut buf_reader = BufReader::new(file);
/// let mut contents = String::new();
/// buf_reader.read_to_string(&mut contents)?;
/// assert_eq!(contents, "Hello, world!");
/// Ok(())
/// }
/// ```
///
/// Note that, although read and write methods require a `&mut File`, because
/// of the interfaces for [`Read`] and [`Write`], the holder of a `&File` can
/// still modify the file, either through methods that take `&File` or by
/// retrieving the underlying OS object and modifying the file that way.
/// Additionally, many operating systems allow concurrent modification of files
/// by different processes. Avoid assuming that holding a `&File` means that the
/// file will not change.
///
/// [`Seek`]: ../io/trait.Seek.html
/// [`String`]: ../string/struct.String.html
/// [`Read`]: ../io/trait.Read.html
/// [`Write`]: ../io/trait.Write.html
/// [`BufReader<R>`]: ../io/struct.BufReader.html
/// [`sync_all`]: struct.File.html#method.sync_all
/// [`read`]: fn.read.html
/// [`write`]: fn.write.html
#[stable(feature = "rust1", since = "1.0.0")]
pub struct File {
inner: fs_imp::File,
}
/// Metadata information about a file.
///
/// This structure is returned from the [`metadata`] or
/// [`symlink_metadata`] function or method and represents known
/// metadata about a file such as its permissions, size, modification
/// times, etc.
///
/// [`metadata`]: fn.metadata.html
/// [`symlink_metadata`]: fn.symlink_metadata.html
#[stable(feature = "rust1", since = "1.0.0")]
#[derive(Clone)]
pub struct Metadata(fs_imp::FileAttr);
/// Iterator over the entries in a directory.
///
/// This iterator is returned from the [`read_dir`] function of this module and
/// will yield instances of [`io::Result`]`<`[`DirEntry`]`>`. Through a [`DirEntry`]
/// information like the entry's path and possibly other metadata can be
/// learned.
///
/// The order in which this iterator returns entries is platform and filesystem
/// dependent.
///
/// # Errors
///
/// This [`io::Result`] will be an [`Err`] if there's some sort of intermittent
/// IO error during iteration.
///
/// [`read_dir`]: fn.read_dir.html
/// [`DirEntry`]: struct.DirEntry.html
/// [`io::Result`]: ../io/type.Result.html
/// [`Err`]: ../result/enum.Result.html#variant.Err
#[stable(feature = "rust1", since = "1.0.0")]
#[derive(Debug)]
pub struct ReadDir(fs_imp::ReadDir);
/// Entries returned by the [`ReadDir`] iterator.
///
/// [`ReadDir`]: struct.ReadDir.html
///
/// An instance of `DirEntry` represents an entry inside of a directory on the
/// filesystem. Each entry can be inspected via methods to learn about the full
/// path or possibly other metadata through per-platform extension traits.
#[stable(feature = "rust1", since = "1.0.0")]
pub struct DirEntry(fs_imp::DirEntry);
/// Options and flags which can be used to configure how a file is opened.
///
/// This builder exposes the ability to configure how a [`File`] is opened and
/// what operations are permitted on the open file. The [`File::open`] and
/// [`File::create`] methods are aliases for commonly used options using this
/// builder.
///
/// [`File`]: struct.File.html
/// [`File::open`]: struct.File.html#method.open
/// [`File::create`]: struct.File.html#method.create
///
/// Generally speaking, when using `OpenOptions`, you'll first call [`new`],
/// then chain calls to methods to set each option, then call [`open`],
/// passing the path of the file you're trying to open. This will give you a
/// [`io::Result`][result] with a [`File`][file] inside that you can further
/// operate on.
///
/// [`new`]: struct.OpenOptions.html#method.new
/// [`open`]: struct.OpenOptions.html#method.open
/// [result]: ../io/type.Result.html
/// [file]: struct.File.html
///
/// # Examples
///
/// Opening a file to read:
///
/// ```no_run
/// use std::fs::OpenOptions;
///
/// let file = OpenOptions::new().read(true).open("foo.txt");
/// ```
///
/// Opening a file for both reading and writing, as well as creating it if it
/// doesn't exist:
///
/// ```no_run
/// use std::fs::OpenOptions;
///
/// let file = OpenOptions::new()
/// .read(true)
/// .write(true)
/// .create(true)
/// .open("foo.txt");
/// ```
#[derive(Clone, Debug)]
#[stable(feature = "rust1", since = "1.0.0")]
pub struct OpenOptions(fs_imp::OpenOptions);
/// Representation of the various permissions on a file.
///
/// This module only currently provides one bit of information, [`readonly`],
/// which is exposed on all currently supported platforms. Unix-specific
/// functionality, such as mode bits, is available through the
/// [`PermissionsExt`] trait.
///
/// [`readonly`]: struct.Permissions.html#method.readonly
/// [`PermissionsExt`]: ../os/unix/fs/trait.PermissionsExt.html
#[derive(Clone, PartialEq, Eq, Debug)]
#[stable(feature = "rust1", since = "1.0.0")]
pub struct Permissions(fs_imp::FilePermissions);
/// A structure representing a type of file with accessors for each file type.
/// It is returned by [`Metadata::file_type`] method.
///
/// [`Metadata::file_type`]: struct.Metadata.html#method.file_type
#[stable(feature = "file_type", since = "1.1.0")]
#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug)]
pub struct FileType(fs_imp::FileType);
/// A builder used to create directories in various manners.
///
/// This builder also supports platform-specific options.
#[stable(feature = "dir_builder", since = "1.6.0")]
#[derive(Debug)]
pub struct DirBuilder {
inner: fs_imp::DirBuilder,
recursive: bool,
}
/// Indicates how large a buffer to pre-allocate before reading the entire file.
fn initial_buffer_size(file: &File) -> usize {
// Allocate one extra byte so the buffer doesn't need to grow before the
// final `read` call at the end of the file. Don't worry about `usize`
// overflow because reading will fail regardless in that case.
file.metadata().map(|m| m.len() as usize + 1).unwrap_or(0)
}
/// Read the entire contents of a file into a bytes vector.
///
/// This is a convenience function for using [`File::open`] and [`read_to_end`]
/// with fewer imports and without an intermediate variable. It pre-allocates a
/// buffer based on the file size when available, so it is generally faster than
/// reading into a vector created with `Vec::new()`.
///
/// [`File::open`]: struct.File.html#method.open
/// [`read_to_end`]: ../io/trait.Read.html#method.read_to_end
///
/// # Errors
///
/// This function will return an error if `path` does not already exist.
/// Other errors may also be returned according to [`OpenOptions::open`].
///
/// [`OpenOptions::open`]: struct.OpenOptions.html#method.open
///
/// It will also return an error if it encounters while reading an error
/// of a kind other than [`ErrorKind::Interrupted`].
///
/// [`ErrorKind::Interrupted`]: ../../std/io/enum.ErrorKind.html#variant.Interrupted
///
/// # Examples
///
/// ```no_run
/// use std::fs;
/// use std::net::SocketAddr;
///
/// fn main() -> Result<(), Box<dyn std::error::Error + 'static>> {
/// let foo: SocketAddr = String::from_utf8_lossy(&fs::read("address.txt")?).parse()?;
/// Ok(())
/// }
/// ```
#[stable(feature = "fs_read_write_bytes", since = "1.26.0")]
pub fn read<P: AsRef<Path>>(path: P) -> io::Result<Vec<u8>> {
fn inner(path: &Path) -> io::Result<Vec<u8>> {
let mut file = File::open(path)?;
let mut bytes = Vec::with_capacity(initial_buffer_size(&file));
file.read_to_end(&mut bytes)?;
Ok(bytes)
}
inner(path.as_ref())
}
/// Read the entire contents of a file into a string.
///
/// This is a convenience function for using [`File::open`] and [`read_to_string`]
/// with fewer imports and without an intermediate variable. It pre-allocates a
/// buffer based on the file size when available, so it is generally faster than
/// reading into a string created with `String::new()`.
///
/// [`File::open`]: struct.File.html#method.open
/// [`read_to_string`]: ../io/trait.Read.html#method.read_to_string
///
/// # Errors
///
/// This function will return an error if `path` does not already exist.
/// Other errors may also be returned according to [`OpenOptions::open`].
///
/// [`OpenOptions::open`]: struct.OpenOptions.html#method.open
///
/// It will also return an error if it encounters while reading an error
/// of a kind other than [`ErrorKind::Interrupted`],
/// or if the contents of the file are not valid UTF-8.
///
/// [`ErrorKind::Interrupted`]: ../../std/io/enum.ErrorKind.html#variant.Interrupted
///
/// # Examples
///
/// ```no_run
/// use std::fs;
/// use std::net::SocketAddr;
///
/// fn main() -> Result<(), Box<dyn std::error::Error + 'static>> {
/// let foo: SocketAddr = fs::read_to_string("address.txt")?.parse()?;
/// Ok(())
/// }
/// ```
#[stable(feature = "fs_read_write", since = "1.26.0")]
pub fn read_to_string<P: AsRef<Path>>(path: P) -> io::Result<String> {
fn inner(path: &Path) -> io::Result<String> {
let mut file = File::open(path)?;
let mut string = String::with_capacity(initial_buffer_size(&file));
file.read_to_string(&mut string)?;
Ok(string)
}
inner(path.as_ref())
}
/// Write a slice as the entire contents of a file.
///
/// This function will create a file if it does not exist,
/// and will entirely replace its contents if it does.
///
/// This is a convenience function for using [`File::create`] and [`write_all`]
/// with fewer imports.
///
/// [`File::create`]: struct.File.html#method.create
/// [`write_all`]: ../io/trait.Write.html#method.write_all
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// fs::write("foo.txt", b"Lorem ipsum")?;
/// fs::write("bar.txt", "dolor sit")?;
/// Ok(())
/// }
/// ```
#[stable(feature = "fs_read_write_bytes", since = "1.26.0")]
pub fn write<P: AsRef<Path>, C: AsRef<[u8]>>(path: P, contents: C) -> io::Result<()> {
fn inner(path: &Path, contents: &[u8]) -> io::Result<()> {
File::create(path)?.write_all(contents)
}
inner(path.as_ref(), contents.as_ref())
}
impl File {
/// Attempts to open a file in read-only mode.
///
/// See the [`OpenOptions::open`] method for more details.
///
/// # Errors
///
/// This function will return an error if `path` does not already exist.
/// Other errors may also be returned according to [`OpenOptions::open`].
///
/// [`OpenOptions::open`]: struct.OpenOptions.html#method.open
///
/// # Examples
///
/// ```no_run
/// use std::fs::File;
///
/// fn main() -> std::io::Result<()> {
/// let mut f = File::open("foo.txt")?;
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn open<P: AsRef<Path>>(path: P) -> io::Result<File> {
OpenOptions::new().read(true).open(path.as_ref())
}
/// Opens a file in write-only mode.
///
/// This function will create a file if it does not exist,
/// and will truncate it if it does.
///
/// See the [`OpenOptions::open`] function for more details.
///
/// [`OpenOptions::open`]: struct.OpenOptions.html#method.open
///
/// # Examples
///
/// ```no_run
/// use std::fs::File;
///
/// fn main() -> std::io::Result<()> {
/// let mut f = File::create("foo.txt")?;
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn create<P: AsRef<Path>>(path: P) -> io::Result<File> {
OpenOptions::new().write(true).create(true).truncate(true).open(path.as_ref())
}
/// Returns a new OpenOptions object.
///
/// This function returns a new OpenOptions object that you can use to
/// open or create a file with specific options if `open()` or `create()`
/// are not appropriate.
///
/// It is equivalent to `OpenOptions::new()` but allows you to write more
/// readable code. Instead of `OpenOptions::new().read(true).open("foo.txt")`
/// you can write `File::with_options().read(true).open("foo.txt")`. This
/// also avoids the need to import `OpenOptions`.
///
/// See the [`OpenOptions::new`] function for more details.
///
/// [`OpenOptions::new`]: struct.OpenOptions.html#method.new
///
/// # Examples
///
/// ```no_run
/// #![feature(with_options)]
/// use std::fs::File;
///
/// fn main() -> std::io::Result<()> {
/// let mut f = File::with_options().read(true).open("foo.txt")?;
/// Ok(())
/// }
/// ```
#[unstable(feature = "with_options", issue = "65439")]
pub fn with_options() -> OpenOptions {
OpenOptions::new()
}
/// Attempts to sync all OS-internal metadata to disk.
///
/// This function will attempt to ensure that all in-memory data reaches the
/// filesystem before returning.
///
/// This can be used to handle errors that would otherwise only be caught
/// when the `File` is closed. Dropping a file will ignore errors in
/// synchronizing this in-memory data.
///
/// # Examples
///
/// ```no_run
/// use std::fs::File;
/// use std::io::prelude::*;
///
/// fn main() -> std::io::Result<()> {
/// let mut f = File::create("foo.txt")?;
/// f.write_all(b"Hello, world!")?;
///
/// f.sync_all()?;
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn sync_all(&self) -> io::Result<()> {
self.inner.fsync()
}
/// This function is similar to [`sync_all`], except that it may not
/// synchronize file metadata to the filesystem.
///
/// This is intended for use cases that must synchronize content, but don't
/// need the metadata on disk. The goal of this method is to reduce disk
/// operations.
///
/// Note that some platforms may simply implement this in terms of
/// [`sync_all`].
///
/// [`sync_all`]: struct.File.html#method.sync_all
///
/// # Examples
///
/// ```no_run
/// use std::fs::File;
/// use std::io::prelude::*;
///
/// fn main() -> std::io::Result<()> {
/// let mut f = File::create("foo.txt")?;
/// f.write_all(b"Hello, world!")?;
///
/// f.sync_data()?;
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn sync_data(&self) -> io::Result<()> {
self.inner.datasync()
}
/// Truncates or extends the underlying file, updating the size of
/// this file to become `size`.
///
/// If the `size` is less than the current file's size, then the file will
/// be shrunk. If it is greater than the current file's size, then the file
/// will be extended to `size` and have all of the intermediate data filled
/// in with 0s.
///
/// The file's cursor isn't changed. In particular, if the cursor was at the
/// end and the file is shrunk using this operation, the cursor will now be
/// past the end.
///
/// # Errors
///
/// This function will return an error if the file is not opened for writing.
/// Also, std::io::ErrorKind::InvalidInput will be returned if the desired
/// length would cause an overflow due to the implementation specifics.
///
/// # Examples
///
/// ```no_run
/// use std::fs::File;
///
/// fn main() -> std::io::Result<()> {
/// let mut f = File::create("foo.txt")?;
/// f.set_len(10)?;
/// Ok(())
/// }
/// ```
///
/// Note that this method alters the content of the underlying file, even
/// though it takes `&self` rather than `&mut self`.
#[stable(feature = "rust1", since = "1.0.0")]
pub fn set_len(&self, size: u64) -> io::Result<()> {
self.inner.truncate(size)
}
/// Queries metadata about the underlying file.
///
/// # Examples
///
/// ```no_run
/// use std::fs::File;
///
/// fn main() -> std::io::Result<()> {
/// let mut f = File::open("foo.txt")?;
/// let metadata = f.metadata()?;
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn metadata(&self) -> io::Result<Metadata> {
self.inner.file_attr().map(Metadata)
}
/// Creates a new `File` instance that shares the same underlying file handle
/// as the existing `File` instance. Reads, writes, and seeks will affect
/// both `File` instances simultaneously.
///
/// # Examples
///
/// Creates two handles for a file named `foo.txt`:
///
/// ```no_run
/// use std::fs::File;
///
/// fn main() -> std::io::Result<()> {
/// let mut file = File::open("foo.txt")?;
/// let file_copy = file.try_clone()?;
/// Ok(())
/// }
/// ```
///
/// Assuming there’s a file named `foo.txt` with contents `abcdef\n`, create
/// two handles, seek one of them, and read the remaining bytes from the
/// other handle:
///
/// ```no_run
/// use std::fs::File;
/// use std::io::SeekFrom;
/// use std::io::prelude::*;
///
/// fn main() -> std::io::Result<()> {
/// let mut file = File::open("foo.txt")?;
/// let mut file_copy = file.try_clone()?;
///
/// file.seek(SeekFrom::Start(3))?;
///
/// let mut contents = vec![];
/// file_copy.read_to_end(&mut contents)?;
/// assert_eq!(contents, b"def\n");
/// Ok(())
/// }
/// ```
#[stable(feature = "file_try_clone", since = "1.9.0")]
pub fn try_clone(&self) -> io::Result<File> {
Ok(File { inner: self.inner.duplicate()? })
}
/// Changes the permissions on the underlying file.
///
/// # Platform-specific behavior
///
/// This function currently corresponds to the `fchmod` function on Unix and
/// the `SetFileInformationByHandle` function on Windows. Note that, this
/// [may change in the future][changes].
///
/// [changes]: ../io/index.html#platform-specific-behavior
///
/// # Errors
///
/// This function will return an error if the user lacks permission change
/// attributes on the underlying file. It may also return an error in other
/// os-specific unspecified cases.
///
/// # Examples
///
/// ```no_run
/// fn main() -> std::io::Result<()> {
/// use std::fs::File;
///
/// let file = File::open("foo.txt")?;
/// let mut perms = file.metadata()?.permissions();
/// perms.set_readonly(true);
/// file.set_permissions(perms)?;
/// Ok(())
/// }
/// ```
///
/// Note that this method alters the permissions of the underlying file,
/// even though it takes `&self` rather than `&mut self`.
#[stable(feature = "set_permissions_atomic", since = "1.16.0")]
pub fn set_permissions(&self, perm: Permissions) -> io::Result<()> {
self.inner.set_permissions(perm.0)
}
}
impl AsInner<fs_imp::File> for File {
fn as_inner(&self) -> &fs_imp::File {
&self.inner
}
}
impl FromInner<fs_imp::File> for File {
fn from_inner(f: fs_imp::File) -> File {
File { inner: f }
}
}
impl IntoInner<fs_imp::File> for File {
fn into_inner(self) -> fs_imp::File {
self.inner
}
}
#[stable(feature = "rust1", since = "1.0.0")]
impl fmt::Debug for File {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
self.inner.fmt(f)
}
}
#[stable(feature = "rust1", since = "1.0.0")]
impl Read for File {
fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
self.inner.read(buf)
}
fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> io::Result<usize> {
self.inner.read_vectored(bufs)
}
#[inline]
fn is_read_vectored(&self) -> bool {
self.inner.is_read_vectored()
}
#[inline]
unsafe fn initializer(&self) -> Initializer {
// SAFETY: Read is guaranteed to work on uninitialized memory
unsafe { Initializer::nop() }
}
}
#[stable(feature = "rust1", since = "1.0.0")]
impl Write for File {
fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
self.inner.write(buf)
}
fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> io::Result<usize> {
self.inner.write_vectored(bufs)
}
#[inline]
fn is_write_vectored(&self) -> bool {
self.inner.is_write_vectored()
}
fn flush(&mut self) -> io::Result<()> {
self.inner.flush()
}
}
#[stable(feature = "rust1", since = "1.0.0")]
impl Seek for File {
fn seek(&mut self, pos: SeekFrom) -> io::Result<u64> {
self.inner.seek(pos)
}
}
#[stable(feature = "rust1", since = "1.0.0")]
impl Read for &File {
fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
self.inner.read(buf)
}
fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> io::Result<usize> {
self.inner.read_vectored(bufs)
}
#[inline]
fn is_read_vectored(&self) -> bool {
self.inner.is_read_vectored()
}
#[inline]
unsafe fn initializer(&self) -> Initializer {
// SAFETY: Read is guaranteed to work on uninitialized memory
unsafe { Initializer::nop() }
}
}
#[stable(feature = "rust1", since = "1.0.0")]
impl Write for &File {
fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
self.inner.write(buf)
}
fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> io::Result<usize> {
self.inner.write_vectored(bufs)
}
#[inline]
fn is_write_vectored(&self) -> bool {
self.inner.is_write_vectored()
}
fn flush(&mut self) -> io::Result<()> {
self.inner.flush()
}
}
#[stable(feature = "rust1", since = "1.0.0")]
impl Seek for &File {
fn seek(&mut self, pos: SeekFrom) -> io::Result<u64> {
self.inner.seek(pos)
}
}
impl OpenOptions {
/// Creates a blank new set of options ready for configuration.
///
/// All options are initially set to `false`.
///
/// # Examples
///
/// ```no_run
/// use std::fs::OpenOptions;
///
/// let mut options = OpenOptions::new();
/// let file = options.read(true).open("foo.txt");
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn new() -> Self {
OpenOptions(fs_imp::OpenOptions::new())
}
/// Sets the option for read access.
///
/// This option, when true, will indicate that the file should be
/// `read`-able if opened.
///
/// # Examples
///
/// ```no_run
/// use std::fs::OpenOptions;
///
/// let file = OpenOptions::new().read(true).open("foo.txt");
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn read(&mut self, read: bool) -> &mut Self {
self.0.read(read);
self
}
/// Sets the option for write access.
///
/// This option, when true, will indicate that the file should be
/// `write`-able if opened.
///
/// If the file already exists, any write calls on it will overwrite its
/// contents, without truncating it.
///
/// # Examples
///
/// ```no_run
/// use std::fs::OpenOptions;
///
/// let file = OpenOptions::new().write(true).open("foo.txt");
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn write(&mut self, write: bool) -> &mut Self {
self.0.write(write);
self
}
/// Sets the option for the append mode.
///
/// This option, when true, means that writes will append to a file instead
/// of overwriting previous contents.
/// Note that setting `.write(true).append(true)` has the same effect as
/// setting only `.append(true)`.
///
/// For most filesystems, the operating system guarantees that all writes are
/// atomic: no writes get mangled because another process writes at the same
/// time.
///
/// One maybe obvious note when using append-mode: make sure that all data
/// that belongs together is written to the file in one operation. This
/// can be done by concatenating strings before passing them to [`write()`],
/// or using a buffered writer (with a buffer of adequate size),
/// and calling [`flush()`] when the message is complete.
///
/// If a file is opened with both read and append access, beware that after
/// opening, and after every write, the position for reading may be set at the
/// end of the file. So, before writing, save the current position (using
/// [`seek`]`(`[`SeekFrom`]`::`[`Current`]`(0))`), and restore it before the next read.
///
/// ## Note
///
/// This function doesn't create the file if it doesn't exist. Use the [`create`]
/// method to do so.
///
/// [`write()`]: ../../std/fs/struct.File.html#method.write
/// [`flush()`]: ../../std/fs/struct.File.html#method.flush
/// [`seek`]: ../../std/fs/struct.File.html#method.seek
/// [`SeekFrom`]: ../../std/io/enum.SeekFrom.html
/// [`Current`]: ../../std/io/enum.SeekFrom.html#variant.Current
/// [`create`]: #method.create
///
/// # Examples
///
/// ```no_run
/// use std::fs::OpenOptions;
///
/// let file = OpenOptions::new().append(true).open("foo.txt");
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn append(&mut self, append: bool) -> &mut Self {
self.0.append(append);
self
}
/// Sets the option for truncating a previous file.
///
/// If a file is successfully opened with this option set it will truncate
/// the file to 0 length if it already exists.
///
/// The file must be opened with write access for truncate to work.
///
/// # Examples
///
/// ```no_run
/// use std::fs::OpenOptions;
///
/// let file = OpenOptions::new().write(true).truncate(true).open("foo.txt");
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn truncate(&mut self, truncate: bool) -> &mut Self {
self.0.truncate(truncate);
self
}
/// Sets the option to create a new file, or open it if it already exists.
///
/// In order for the file to be created, [`write`] or [`append`] access must
/// be used.
///
/// [`write`]: #method.write
/// [`append`]: #method.append
///
/// # Examples
///
/// ```no_run
/// use std::fs::OpenOptions;
///
/// let file = OpenOptions::new().write(true).create(true).open("foo.txt");
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn create(&mut self, create: bool) -> &mut Self {
self.0.create(create);
self
}
/// Sets the option to create a new file, failing if it already exists.
///
/// No file is allowed to exist at the target location, also no (dangling) symlink. In this
/// way, if the call succeeds, the file returned is guaranteed to be new.
///
/// This option is useful because it is atomic. Otherwise between checking
/// whether a file exists and creating a new one, the file may have been
/// created by another process (a TOCTOU race condition / attack).
///
/// If `.create_new(true)` is set, [`.create()`] and [`.truncate()`] are
/// ignored.
///
/// The file must be opened with write or append access in order to create
/// a new file.
///
/// [`.create()`]: #method.create
/// [`.truncate()`]: #method.truncate
///
/// # Examples
///
/// ```no_run
/// use std::fs::OpenOptions;
///
/// let file = OpenOptions::new().write(true)
/// .create_new(true)
/// .open("foo.txt");
/// ```
#[stable(feature = "expand_open_options2", since = "1.9.0")]
pub fn create_new(&mut self, create_new: bool) -> &mut Self {
self.0.create_new(create_new);
self
}
/// Opens a file at `path` with the options specified by `self`.
///
/// # Errors
///
/// This function will return an error under a number of different
/// circumstances. Some of these error conditions are listed here, together
/// with their [`ErrorKind`]. The mapping to [`ErrorKind`]s is not part of
/// the compatibility contract of the function, especially the `Other` kind
/// might change to more specific kinds in the future.
///
/// * [`NotFound`]: The specified file does not exist and neither `create`
/// or `create_new` is set.
/// * [`NotFound`]: One of the directory components of the file path does
/// not exist.
/// * [`PermissionDenied`]: The user lacks permission to get the specified
/// access rights for the file.
/// * [`PermissionDenied`]: The user lacks permission to open one of the
/// directory components of the specified path.
/// * [`AlreadyExists`]: `create_new` was specified and the file already
/// exists.
/// * [`InvalidInput`]: Invalid combinations of open options (truncate
/// without write access, no access mode set, etc.).
/// * [`Other`]: One of the directory components of the specified file path
/// was not, in fact, a directory.
/// * [`Other`]: Filesystem-level errors: full disk, write permission
/// requested on a read-only file system, exceeded disk quota, too many
/// open files, too long filename, too many symbolic links in the
/// specified path (Unix-like systems only), etc.
///
/// # Examples
///
/// ```no_run
/// use std::fs::OpenOptions;
///
/// let file = OpenOptions::new().read(true).open("foo.txt");
/// ```
///
/// [`ErrorKind`]: ../io/enum.ErrorKind.html
/// [`AlreadyExists`]: ../io/enum.ErrorKind.html#variant.AlreadyExists
/// [`InvalidInput`]: ../io/enum.ErrorKind.html#variant.InvalidInput
/// [`NotFound`]: ../io/enum.ErrorKind.html#variant.NotFound
/// [`Other`]: ../io/enum.ErrorKind.html#variant.Other
/// [`PermissionDenied`]: ../io/enum.ErrorKind.html#variant.PermissionDenied
#[stable(feature = "rust1", since = "1.0.0")]
pub fn open<P: AsRef<Path>>(&self, path: P) -> io::Result<File> {
self._open(path.as_ref())
}
fn _open(&self, path: &Path) -> io::Result<File> {
fs_imp::File::open(path, &self.0).map(|inner| File { inner })
}
}
impl AsInner<fs_imp::OpenOptions> for OpenOptions {
fn as_inner(&self) -> &fs_imp::OpenOptions {
&self.0
}
}
impl AsInnerMut<fs_imp::OpenOptions> for OpenOptions {
fn as_inner_mut(&mut self) -> &mut fs_imp::OpenOptions {
&mut self.0
}
}
impl Metadata {
/// Returns the file type for this metadata.
///
/// # Examples
///
/// ```no_run
/// fn main() -> std::io::Result<()> {
/// use std::fs;
///
/// let metadata = fs::metadata("foo.txt")?;
///
/// println!("{:?}", metadata.file_type());
/// Ok(())
/// }
/// ```
#[stable(feature = "file_type", since = "1.1.0")]
pub fn file_type(&self) -> FileType {
FileType(self.0.file_type())
}
/// Returns `true` if this metadata is for a directory. The
/// result is mutually exclusive to the result of
/// [`is_file`], and will be false for symlink metadata
/// obtained from [`symlink_metadata`].
///
/// [`is_file`]: struct.Metadata.html#method.is_file
/// [`symlink_metadata`]: fn.symlink_metadata.html
///
/// # Examples
///
/// ```no_run
/// fn main() -> std::io::Result<()> {
/// use std::fs;
///
/// let metadata = fs::metadata("foo.txt")?;
///
/// assert!(!metadata.is_dir());
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn is_dir(&self) -> bool {
self.file_type().is_dir()
}
/// Returns `true` if this metadata is for a regular file. The
/// result is mutually exclusive to the result of
/// [`is_dir`], and will be false for symlink metadata
/// obtained from [`symlink_metadata`].
///
/// When the goal is simply to read from (or write to) the source, the most
/// reliable way to test the source can be read (or written to) is to open
/// it. Only using `is_file` can break workflows like `diff <( prog_a )` on
/// a Unix-like system for example. See [`File::open`] or
/// [`OpenOptions::open`] for more information.
///
/// [`is_dir`]: struct.Metadata.html#method.is_dir
/// [`symlink_metadata`]: fn.symlink_metadata.html
/// [`File::open`]: struct.File.html#method.open
/// [`OpenOptions::open`]: struct.OpenOptions.html#method.open
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// let metadata = fs::metadata("foo.txt")?;
///
/// assert!(metadata.is_file());
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn is_file(&self) -> bool {
self.file_type().is_file()
}
/// Returns the size of the file, in bytes, this metadata is for.
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// let metadata = fs::metadata("foo.txt")?;
///
/// assert_eq!(0, metadata.len());
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn len(&self) -> u64 {
self.0.size()
}
/// Returns the permissions of the file this metadata is for.
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// let metadata = fs::metadata("foo.txt")?;
///
/// assert!(!metadata.permissions().readonly());
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn permissions(&self) -> Permissions {
Permissions(self.0.perm())
}
/// Returns the last modification time listed in this metadata.
///
/// The returned value corresponds to the `mtime` field of `stat` on Unix
/// platforms and the `ftLastWriteTime` field on Windows platforms.
///
/// # Errors
///
/// This field may not be available on all platforms, and will return an
/// `Err` on platforms where it is not available.
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// let metadata = fs::metadata("foo.txt")?;
///
/// if let Ok(time) = metadata.modified() {
/// println!("{:?}", time);
/// } else {
/// println!("Not supported on this platform");
/// }
/// Ok(())
/// }
/// ```
#[stable(feature = "fs_time", since = "1.10.0")]
pub fn modified(&self) -> io::Result<SystemTime> {
self.0.modified().map(FromInner::from_inner)
}
/// Returns the last access time of this metadata.
///
/// The returned value corresponds to the `atime` field of `stat` on Unix
/// platforms and the `ftLastAccessTime` field on Windows platforms.
///
/// Note that not all platforms will keep this field update in a file's
/// metadata, for example Windows has an option to disable updating this
/// time when files are accessed and Linux similarly has `noatime`.
///
/// # Errors
///
/// This field may not be available on all platforms, and will return an
/// `Err` on platforms where it is not available.
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// let metadata = fs::metadata("foo.txt")?;
///
/// if let Ok(time) = metadata.accessed() {
/// println!("{:?}", time);
/// } else {
/// println!("Not supported on this platform");
/// }
/// Ok(())
/// }
/// ```
#[stable(feature = "fs_time", since = "1.10.0")]
pub fn accessed(&self) -> io::Result<SystemTime> {
self.0.accessed().map(FromInner::from_inner)
}
/// Returns the creation time listed in this metadata.
///
/// The returned value corresponds to the `btime` field of `statx` on
/// Linux kernel starting from to 4.11, the `birthtime` field of `stat` on other
/// Unix platforms, and the `ftCreationTime` field on Windows platforms.
///
/// # Errors
///
/// This field may not be available on all platforms, and will return an
/// `Err` on platforms or filesystems where it is not available.
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// let metadata = fs::metadata("foo.txt")?;
///
/// if let Ok(time) = metadata.created() {
/// println!("{:?}", time);
/// } else {
/// println!("Not supported on this platform or filesystem");
/// }
/// Ok(())
/// }
/// ```
#[stable(feature = "fs_time", since = "1.10.0")]
pub fn created(&self) -> io::Result<SystemTime> {
self.0.created().map(FromInner::from_inner)
}
}
#[stable(feature = "std_debug", since = "1.16.0")]
impl fmt::Debug for Metadata {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_struct("Metadata")
.field("file_type", &self.file_type())
.field("is_dir", &self.is_dir())
.field("is_file", &self.is_file())
.field("permissions", &self.permissions())
.field("modified", &self.modified())
.field("accessed", &self.accessed())
.field("created", &self.created())
.finish()
}
}
impl AsInner<fs_imp::FileAttr> for Metadata {
fn as_inner(&self) -> &fs_imp::FileAttr {
&self.0
}
}
impl FromInner<fs_imp::FileAttr> for Metadata {
fn from_inner(attr: fs_imp::FileAttr) -> Metadata {
Metadata(attr)
}
}
impl Permissions {
/// Returns `true` if these permissions describe a readonly (unwritable) file.
///
/// # Examples
///
/// ```no_run
/// use std::fs::File;
///
/// fn main() -> std::io::Result<()> {
/// let mut f = File::create("foo.txt")?;
/// let metadata = f.metadata()?;
///
/// assert_eq!(false, metadata.permissions().readonly());
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn readonly(&self) -> bool {
self.0.readonly()
}
/// Modifies the readonly flag for this set of permissions. If the
/// `readonly` argument is `true`, using the resulting `Permission` will
/// update file permissions to forbid writing. Conversely, if it's `false`,
/// using the resulting `Permission` will update file permissions to allow
/// writing.
///
/// This operation does **not** modify the filesystem. To modify the
/// filesystem use the [`fs::set_permissions`] function.
///
/// [`fs::set_permissions`]: fn.set_permissions.html
///
/// # Examples
///
/// ```no_run
/// use std::fs::File;
///
/// fn main() -> std::io::Result<()> {
/// let f = File::create("foo.txt")?;
/// let metadata = f.metadata()?;
/// let mut permissions = metadata.permissions();
///
/// permissions.set_readonly(true);
///
/// // filesystem doesn't change
/// assert_eq!(false, metadata.permissions().readonly());
///
/// // just this particular `permissions`.
/// assert_eq!(true, permissions.readonly());
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn set_readonly(&mut self, readonly: bool) {
self.0.set_readonly(readonly)
}
}
impl FileType {
/// Tests whether this file type represents a directory. The
/// result is mutually exclusive to the results of
/// [`is_file`] and [`is_symlink`]; only zero or one of these
/// tests may pass.
///
/// [`is_file`]: struct.FileType.html#method.is_file
/// [`is_symlink`]: struct.FileType.html#method.is_symlink
///
/// # Examples
///
/// ```no_run
/// fn main() -> std::io::Result<()> {
/// use std::fs;
///
/// let metadata = fs::metadata("foo.txt")?;
/// let file_type = metadata.file_type();
///
/// assert_eq!(file_type.is_dir(), false);
/// Ok(())
/// }
/// ```
#[stable(feature = "file_type", since = "1.1.0")]
pub fn is_dir(&self) -> bool {
self.0.is_dir()
}
/// Tests whether this file type represents a regular file.
/// The result is mutually exclusive to the results of
/// [`is_dir`] and [`is_symlink`]; only zero or one of these
/// tests may pass.
///
/// When the goal is simply to read from (or write to) the source, the most
/// reliable way to test the source can be read (or written to) is to open
/// it. Only using `is_file` can break workflows like `diff <( prog_a )` on
/// a Unix-like system for example. See [`File::open`] or
/// [`OpenOptions::open`] for more information.
///
/// [`is_dir`]: struct.FileType.html#method.is_dir
/// [`is_symlink`]: struct.FileType.html#method.is_symlink
/// [`File::open`]: struct.File.html#method.open
/// [`OpenOptions::open`]: struct.OpenOptions.html#method.open
///
/// # Examples
///
/// ```no_run
/// fn main() -> std::io::Result<()> {
/// use std::fs;
///
/// let metadata = fs::metadata("foo.txt")?;
/// let file_type = metadata.file_type();
///
/// assert_eq!(file_type.is_file(), true);
/// Ok(())
/// }
/// ```
#[stable(feature = "file_type", since = "1.1.0")]
pub fn is_file(&self) -> bool {
self.0.is_file()
}
/// Tests whether this file type represents a symbolic link.
/// The result is mutually exclusive to the results of
/// [`is_dir`] and [`is_file`]; only zero or one of these
/// tests may pass.
///
/// The underlying [`Metadata`] struct needs to be retrieved
/// with the [`fs::symlink_metadata`] function and not the
/// [`fs::metadata`] function. The [`fs::metadata`] function
/// follows symbolic links, so [`is_symlink`] would always
/// return `false` for the target file.
///
/// [`Metadata`]: struct.Metadata.html
/// [`fs::metadata`]: fn.metadata.html
/// [`fs::symlink_metadata`]: fn.symlink_metadata.html
/// [`is_dir`]: struct.FileType.html#method.is_dir
/// [`is_file`]: struct.FileType.html#method.is_file
/// [`is_symlink`]: struct.FileType.html#method.is_symlink
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// let metadata = fs::symlink_metadata("foo.txt")?;
/// let file_type = metadata.file_type();
///
/// assert_eq!(file_type.is_symlink(), false);
/// Ok(())
/// }
/// ```
#[stable(feature = "file_type", since = "1.1.0")]
pub fn is_symlink(&self) -> bool {
self.0.is_symlink()
}
}
impl AsInner<fs_imp::FileType> for FileType {
fn as_inner(&self) -> &fs_imp::FileType {
&self.0
}
}
impl FromInner<fs_imp::FilePermissions> for Permissions {
fn from_inner(f: fs_imp::FilePermissions) -> Permissions {
Permissions(f)
}
}
impl AsInner<fs_imp::FilePermissions> for Permissions {
fn as_inner(&self) -> &fs_imp::FilePermissions {
&self.0
}
}
#[stable(feature = "rust1", since = "1.0.0")]
impl Iterator for ReadDir {
type Item = io::Result<DirEntry>;
fn next(&mut self) -> Option<io::Result<DirEntry>> {
self.0.next().map(|entry| entry.map(DirEntry))
}
}
impl DirEntry {
/// Returns the full path to the file that this entry represents.
///
/// The full path is created by joining the original path to `read_dir`
/// with the filename of this entry.
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// for entry in fs::read_dir(".")? {
/// let dir = entry?;
/// println!("{:?}", dir.path());
/// }
/// Ok(())
/// }
/// ```
///
/// This prints output like:
///
/// ```text
/// "./whatever.txt"
/// "./foo.html"
/// "./hello_world.rs"
/// ```
///
/// The exact text, of course, depends on what files you have in `.`.
#[stable(feature = "rust1", since = "1.0.0")]
pub fn path(&self) -> PathBuf {
self.0.path()
}
/// Returns the metadata for the file that this entry points at.
///
/// This function will not traverse symlinks if this entry points at a
/// symlink. To traverse symlinks use [`fs::metadata`] or [`fs::File::metadata`].
///
/// [`fs::metadata`]: fn.metadata.html
/// [`fs::File::metadata`]: struct.File.html#method.metadata
///
/// # Platform-specific behavior
///
/// On Windows this function is cheap to call (no extra system calls
/// needed), but on Unix platforms this function is the equivalent of
/// calling `symlink_metadata` on the path.
///
/// # Examples
///
/// ```
/// use std::fs;
///
/// if let Ok(entries) = fs::read_dir(".") {
/// for entry in entries {
/// if let Ok(entry) = entry {
/// // Here, `entry` is a `DirEntry`.
/// if let Ok(metadata) = entry.metadata() {
/// // Now let's show our entry's permissions!
/// println!("{:?}: {:?}", entry.path(), metadata.permissions());
/// } else {
/// println!("Couldn't get metadata for {:?}", entry.path());
/// }
/// }
/// }
/// }
/// ```
#[stable(feature = "dir_entry_ext", since = "1.1.0")]
pub fn metadata(&self) -> io::Result<Metadata> {
self.0.metadata().map(Metadata)
}
/// Returns the file type for the file that this entry points at.
///
/// This function will not traverse symlinks if this entry points at a
/// symlink.
///
/// # Platform-specific behavior
///
/// On Windows and most Unix platforms this function is free (no extra
/// system calls needed), but some Unix platforms may require the equivalent
/// call to `symlink_metadata` to learn about the target file type.
///
/// # Examples
///
/// ```
/// use std::fs;
///
/// if let Ok(entries) = fs::read_dir(".") {
/// for entry in entries {
/// if let Ok(entry) = entry {
/// // Here, `entry` is a `DirEntry`.
/// if let Ok(file_type) = entry.file_type() {
/// // Now let's show our entry's file type!
/// println!("{:?}: {:?}", entry.path(), file_type);
/// } else {
/// println!("Couldn't get file type for {:?}", entry.path());
/// }
/// }
/// }
/// }
/// ```
#[stable(feature = "dir_entry_ext", since = "1.1.0")]
pub fn file_type(&self) -> io::Result<FileType> {
self.0.file_type().map(FileType)
}
/// Returns the bare file name of this directory entry without any other
/// leading path component.
///
/// # Examples
///
/// ```
/// use std::fs;
///
/// if let Ok(entries) = fs::read_dir(".") {
/// for entry in entries {
/// if let Ok(entry) = entry {
/// // Here, `entry` is a `DirEntry`.
/// println!("{:?}", entry.file_name());
/// }
/// }
/// }
/// ```
#[stable(feature = "dir_entry_ext", since = "1.1.0")]
pub fn file_name(&self) -> OsString {
self.0.file_name()
}
}
#[stable(feature = "dir_entry_debug", since = "1.13.0")]
impl fmt::Debug for DirEntry {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_tuple("DirEntry").field(&self.path()).finish()
}
}
impl AsInner<fs_imp::DirEntry> for DirEntry {
fn as_inner(&self) -> &fs_imp::DirEntry {
&self.0
}
}
/// Removes a file from the filesystem.
///
/// Note that there is no
/// guarantee that the file is immediately deleted (e.g., depending on
/// platform, other open file descriptors may prevent immediate removal).
///
/// # Platform-specific behavior
///
/// This function currently corresponds to the `unlink` function on Unix
/// and the `DeleteFile` function on Windows.
/// Note that, this [may change in the future][changes].
///
/// [changes]: ../io/index.html#platform-specific-behavior
///
/// # Errors
///
/// This function will return an error in the following situations, but is not
/// limited to just these cases:
///
/// * `path` points to a directory.
/// * The user lacks permissions to remove the file.
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// fs::remove_file("a.txt")?;
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn remove_file<P: AsRef<Path>>(path: P) -> io::Result<()> {
fs_imp::unlink(path.as_ref())
}
/// Given a path, query the file system to get information about a file,
/// directory, etc.
///
/// This function will traverse symbolic links to query information about the
/// destination file.
///
/// # Platform-specific behavior
///
/// This function currently corresponds to the `stat` function on Unix
/// and the `GetFileAttributesEx` function on Windows.
/// Note that, this [may change in the future][changes].
///
/// [changes]: ../io/index.html#platform-specific-behavior
///
/// # Errors
///
/// This function will return an error in the following situations, but is not
/// limited to just these cases:
///
/// * The user lacks permissions to perform `metadata` call on `path`.
/// * `path` does not exist.
///
/// # Examples
///
/// ```rust,no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// let attr = fs::metadata("/some/file/path.txt")?;
/// // inspect attr ...
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn metadata<P: AsRef<Path>>(path: P) -> io::Result<Metadata> {
fs_imp::stat(path.as_ref()).map(Metadata)
}
/// Query the metadata about a file without following symlinks.
///
/// # Platform-specific behavior
///
/// This function currently corresponds to the `lstat` function on Unix
/// and the `GetFileAttributesEx` function on Windows.
/// Note that, this [may change in the future][changes].
///
/// [changes]: ../io/index.html#platform-specific-behavior
///
/// # Errors
///
/// This function will return an error in the following situations, but is not
/// limited to just these cases:
///
/// * The user lacks permissions to perform `metadata` call on `path`.
/// * `path` does not exist.
///
/// # Examples
///
/// ```rust,no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// let attr = fs::symlink_metadata("/some/file/path.txt")?;
/// // inspect attr ...
/// Ok(())
/// }
/// ```
#[stable(feature = "symlink_metadata", since = "1.1.0")]
pub fn symlink_metadata<P: AsRef<Path>>(path: P) -> io::Result<Metadata> {
fs_imp::lstat(path.as_ref()).map(Metadata)
}
/// Rename a file or directory to a new name, replacing the original file if
/// `to` already exists.
///
/// This will not work if the new name is on a different mount point.
///
/// # Platform-specific behavior
///
/// This function currently corresponds to the `rename` function on Unix
/// and the `MoveFileEx` function with the `MOVEFILE_REPLACE_EXISTING` flag on Windows.
///
/// Because of this, the behavior when both `from` and `to` exist differs. On
/// Unix, if `from` is a directory, `to` must also be an (empty) directory. If
/// `from` is not a directory, `to` must also be not a directory. In contrast,
/// on Windows, `from` can be anything, but `to` must *not* be a directory.
///
/// Note that, this [may change in the future][changes].
///
/// [changes]: ../io/index.html#platform-specific-behavior
///
/// # Errors
///
/// This function will return an error in the following situations, but is not
/// limited to just these cases:
///
/// * `from` does not exist.
/// * The user lacks permissions to view contents.
/// * `from` and `to` are on separate filesystems.
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// fs::rename("a.txt", "b.txt")?; // Rename a.txt to b.txt
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn rename<P: AsRef<Path>, Q: AsRef<Path>>(from: P, to: Q) -> io::Result<()> {
fs_imp::rename(from.as_ref(), to.as_ref())
}
/// Copies the contents of one file to another. This function will also
/// copy the permission bits of the original file to the destination file.
///
/// This function will **overwrite** the contents of `to`.
///
/// Note that if `from` and `to` both point to the same file, then the file
/// will likely get truncated by this operation.
///
/// On success, the total number of bytes copied is returned and it is equal to
/// the length of the `to` file as reported by `metadata`.
///
/// If you’re wanting to copy the contents of one file to another and you’re
/// working with [`File`]s, see the [`io::copy`] function.
///
/// [`io::copy`]: ../io/fn.copy.html
/// [`File`]: ./struct.File.html
///
/// # Platform-specific behavior
///
/// This function currently corresponds to the `open` function in Unix
/// with `O_RDONLY` for `from` and `O_WRONLY`, `O_CREAT`, and `O_TRUNC` for `to`.
/// `O_CLOEXEC` is set for returned file descriptors.
/// On Windows, this function currently corresponds to `CopyFileEx`. Alternate
/// NTFS streams are copied but only the size of the main stream is returned by
/// this function. On MacOS, this function corresponds to `fclonefileat` and
/// `fcopyfile`.
/// Note that, this [may change in the future][changes].
///
/// [changes]: ../io/index.html#platform-specific-behavior
///
/// # Errors
///
/// This function will return an error in the following situations, but is not
/// limited to just these cases:
///
/// * The `from` path is not a file.
/// * The `from` file does not exist.
/// * The current process does not have the permission rights to access
/// `from` or write `to`.
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// fs::copy("foo.txt", "bar.txt")?; // Copy foo.txt to bar.txt
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn copy<P: AsRef<Path>, Q: AsRef<Path>>(from: P, to: Q) -> io::Result<u64> {
fs_imp::copy(from.as_ref(), to.as_ref())
}
/// Creates a new hard link on the filesystem.
///
/// The `dst` path will be a link pointing to the `src` path. Note that systems
/// often require these two paths to both be located on the same filesystem.
///
/// # Platform-specific behavior
///
/// This function currently corresponds to the `link` function on Unix
/// and the `CreateHardLink` function on Windows.
/// Note that, this [may change in the future][changes].
///
/// [changes]: ../io/index.html#platform-specific-behavior
///
/// # Errors
///
/// This function will return an error in the following situations, but is not
/// limited to just these cases:
///
/// * The `src` path is not a file or doesn't exist.
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// fs::hard_link("a.txt", "b.txt")?; // Hard link a.txt to b.txt
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn hard_link<P: AsRef<Path>, Q: AsRef<Path>>(src: P, dst: Q) -> io::Result<()> {
fs_imp::link(src.as_ref(), dst.as_ref())
}
/// Creates a new symbolic link on the filesystem.
///
/// The `dst` path will be a symbolic link pointing to the `src` path.
/// On Windows, this will be a file symlink, not a directory symlink;
/// for this reason, the platform-specific [`std::os::unix::fs::symlink`]
/// and [`std::os::windows::fs::symlink_file`] or [`symlink_dir`] should be
/// used instead to make the intent explicit.
///
/// [`std::os::unix::fs::symlink`]: ../os/unix/fs/fn.symlink.html
/// [`std::os::windows::fs::symlink_file`]: ../os/windows/fs/fn.symlink_file.html
/// [`symlink_dir`]: ../os/windows/fs/fn.symlink_dir.html
///
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// fs::soft_link("a.txt", "b.txt")?;
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[rustc_deprecated(
since = "1.1.0",
reason = "replaced with std::os::unix::fs::symlink and \
std::os::windows::fs::{symlink_file, symlink_dir}"
)]
pub fn soft_link<P: AsRef<Path>, Q: AsRef<Path>>(src: P, dst: Q) -> io::Result<()> {
fs_imp::symlink(src.as_ref(), dst.as_ref())
}
/// Reads a symbolic link, returning the file that the link points to.
///
/// # Platform-specific behavior
///
/// This function currently corresponds to the `readlink` function on Unix
/// and the `CreateFile` function with `FILE_FLAG_OPEN_REPARSE_POINT` and
/// `FILE_FLAG_BACKUP_SEMANTICS` flags on Windows.
/// Note that, this [may change in the future][changes].
///
/// [changes]: ../io/index.html#platform-specific-behavior
///
/// # Errors
///
/// This function will return an error in the following situations, but is not
/// limited to just these cases:
///
/// * `path` is not a symbolic link.
/// * `path` does not exist.
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// let path = fs::read_link("a.txt")?;
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn read_link<P: AsRef<Path>>(path: P) -> io::Result<PathBuf> {
fs_imp::readlink(path.as_ref())
}
/// Returns the canonical, absolute form of a path with all intermediate
/// components normalized and symbolic links resolved.
///
/// # Platform-specific behavior
///
/// This function currently corresponds to the `realpath` function on Unix
/// and the `CreateFile` and `GetFinalPathNameByHandle` functions on Windows.
/// Note that, this [may change in the future][changes].
///
/// On Windows, this converts the path to use [extended length path][path]
/// syntax, which allows your program to use longer path names, but means you
/// can only join backslash-delimited paths to it, and it may be incompatible
/// with other applications (if passed to the application on the command-line,
/// or written to a file another application may read).
///
/// [changes]: ../io/index.html#platform-specific-behavior
/// [path]: https://docs.microsoft.com/en-us/windows/win32/fileio/naming-a-file
///
/// # Errors
///
/// This function will return an error in the following situations, but is not
/// limited to just these cases:
///
/// * `path` does not exist.
/// * A non-final component in path is not a directory.
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// let path = fs::canonicalize("../a/../foo.txt")?;
/// Ok(())
/// }
/// ```
#[stable(feature = "fs_canonicalize", since = "1.5.0")]
pub fn canonicalize<P: AsRef<Path>>(path: P) -> io::Result<PathBuf> {
fs_imp::canonicalize(path.as_ref())
}
/// Creates a new, empty directory at the provided path
///
/// # Platform-specific behavior
///
/// This function currently corresponds to the `mkdir` function on Unix
/// and the `CreateDirectory` function on Windows.
/// Note that, this [may change in the future][changes].
///
/// [changes]: ../io/index.html#platform-specific-behavior
///
/// **NOTE**: If a parent of the given path doesn't exist, this function will
/// return an error. To create a directory and all its missing parents at the
/// same time, use the [`create_dir_all`] function.
///
/// # Errors
///
/// This function will return an error in the following situations, but is not
/// limited to just these cases:
///
/// * User lacks permissions to create directory at `path`.
/// * A parent of the given path doesn't exist. (To create a directory and all
/// its missing parents at the same time, use the [`create_dir_all`]
/// function.)
/// * `path` already exists.
///
/// [`create_dir_all`]: fn.create_dir_all.html
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// fs::create_dir("/some/dir")?;
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn create_dir<P: AsRef<Path>>(path: P) -> io::Result<()> {
DirBuilder::new().create(path.as_ref())
}
/// Recursively create a directory and all of its parent components if they
/// are missing.
///
/// # Platform-specific behavior
///
/// This function currently corresponds to the `mkdir` function on Unix
/// and the `CreateDirectory` function on Windows.
/// Note that, this [may change in the future][changes].
///
/// [changes]: ../io/index.html#platform-specific-behavior
///
/// # Errors
///
/// This function will return an error in the following situations, but is not
/// limited to just these cases:
///
/// * If any directory in the path specified by `path`
/// does not already exist and it could not be created otherwise. The specific
/// error conditions for when a directory is being created (after it is
/// determined to not exist) are outlined by [`fs::create_dir`].
///
/// Notable exception is made for situations where any of the directories
/// specified in the `path` could not be created as it was being created concurrently.
/// Such cases are considered to be successful. That is, calling `create_dir_all`
/// concurrently from multiple threads or processes is guaranteed not to fail
/// due to a race condition with itself.
///
/// [`fs::create_dir`]: fn.create_dir.html
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// fs::create_dir_all("/some/dir")?;
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn create_dir_all<P: AsRef<Path>>(path: P) -> io::Result<()> {
DirBuilder::new().recursive(true).create(path.as_ref())
}
/// Removes an existing, empty directory.
///
/// # Platform-specific behavior
///
/// This function currently corresponds to the `rmdir` function on Unix
/// and the `RemoveDirectory` function on Windows.
/// Note that, this [may change in the future][changes].
///
/// [changes]: ../io/index.html#platform-specific-behavior
///
/// # Errors
///
/// This function will return an error in the following situations, but is not
/// limited to just these cases:
///
/// * The user lacks permissions to remove the directory at the provided `path`.
/// * The directory isn't empty.
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// fs::remove_dir("/some/dir")?;
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn remove_dir<P: AsRef<Path>>(path: P) -> io::Result<()> {
fs_imp::rmdir(path.as_ref())
}
/// Removes a directory at this path, after removing all its contents. Use
/// carefully!
///
/// This function does **not** follow symbolic links and it will simply remove the
/// symbolic link itself.
///
/// # Platform-specific behavior
///
/// This function currently corresponds to `opendir`, `lstat`, `rm` and `rmdir` functions on Unix
/// and the `FindFirstFile`, `GetFileAttributesEx`, `DeleteFile`, and `RemoveDirectory` functions
/// on Windows.
/// Note that, this [may change in the future][changes].
///
/// [changes]: ../io/index.html#platform-specific-behavior
///
/// # Errors
///
/// See [`fs::remove_file`] and [`fs::remove_dir`].
///
/// [`fs::remove_file`]: fn.remove_file.html
/// [`fs::remove_dir`]: fn.remove_dir.html
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// fs::remove_dir_all("/some/dir")?;
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn remove_dir_all<P: AsRef<Path>>(path: P) -> io::Result<()> {
fs_imp::remove_dir_all(path.as_ref())
}
/// Returns an iterator over the entries within a directory.
///
/// The iterator will yield instances of [`io::Result`]`<`[`DirEntry`]`>`.
/// New errors may be encountered after an iterator is initially constructed.
///
/// [`io::Result`]: ../io/type.Result.html
/// [`DirEntry`]: struct.DirEntry.html
///
/// # Platform-specific behavior
///
/// This function currently corresponds to the `opendir` function on Unix
/// and the `FindFirstFile` function on Windows. Advancing the iterator
/// currently corresponds to `readdir` on Unix and `FindNextFile` on Windows.
/// Note that, this [may change in the future][changes].
///
/// [changes]: ../io/index.html#platform-specific-behavior
///
/// The order in which this iterator returns entries is platform and filesystem
/// dependent.
///
/// # Errors
///
/// This function will return an error in the following situations, but is not
/// limited to just these cases:
///
/// * The provided `path` doesn't exist.
/// * The process lacks permissions to view the contents.
/// * The `path` points at a non-directory file.
///
/// # Examples
///
/// ```
/// use std::io;
/// use std::fs::{self, DirEntry};
/// use std::path::Path;
///
/// // one possible implementation of walking a directory only visiting files
/// fn visit_dirs(dir: &Path, cb: &dyn Fn(&DirEntry)) -> io::Result<()> {
/// if dir.is_dir() {
/// for entry in fs::read_dir(dir)? {
/// let entry = entry?;
/// let path = entry.path();
/// if path.is_dir() {
/// visit_dirs(&path, cb)?;
/// } else {
/// cb(&entry);
/// }
/// }
/// }
/// Ok(())
/// }
/// ```
///
/// ```rust,no_run
/// use std::{fs, io};
///
/// fn main() -> io::Result<()> {
/// let mut entries = fs::read_dir(".")?
/// .map(|res| res.map(|e| e.path()))
/// .collect::<Result<Vec<_>, io::Error>>()?;
///
/// // The order in which `read_dir` returns entries is not guaranteed. If reproducible
/// // ordering is required the entries should be explicitly sorted.
///
/// entries.sort();
///
/// // The entries have now been sorted by their path.
///
/// Ok(())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn read_dir<P: AsRef<Path>>(path: P) -> io::Result<ReadDir> {
fs_imp::readdir(path.as_ref()).map(ReadDir)
}
/// Changes the permissions found on a file or a directory.
///
/// # Platform-specific behavior
///
/// This function currently corresponds to the `chmod` function on Unix
/// and the `SetFileAttributes` function on Windows.
/// Note that, this [may change in the future][changes].
///
/// [changes]: ../io/index.html#platform-specific-behavior
///
/// # Errors
///
/// This function will return an error in the following situations, but is not
/// limited to just these cases:
///
/// * `path` does not exist.
/// * The user lacks the permission to change attributes of the file.
///
/// # Examples
///
/// ```no_run
/// use std::fs;
///
/// fn main() -> std::io::Result<()> {
/// let mut perms = fs::metadata("foo.txt")?.permissions();
/// perms.set_readonly(true);
/// fs::set_permissions("foo.txt", perms)?;
/// Ok(())
/// }
/// ```
#[stable(feature = "set_permissions", since = "1.1.0")]
pub fn set_permissions<P: AsRef<Path>>(path: P, perm: Permissions) -> io::Result<()> {
fs_imp::set_perm(path.as_ref(), perm.0)
}
impl DirBuilder {
/// Creates a new set of options with default mode/security settings for all
/// platforms and also non-recursive.
///
/// # Examples
///
/// ```
/// use std::fs::DirBuilder;
///
/// let builder = DirBuilder::new();
/// ```
#[stable(feature = "dir_builder", since = "1.6.0")]
pub fn new() -> DirBuilder {
DirBuilder { inner: fs_imp::DirBuilder::new(), recursive: false }
}
/// Indicates that directories should be created recursively, creating all
/// parent directories. Parents that do not exist are created with the same
/// security and permissions settings.
///
/// This option defaults to `false`.
///
/// # Examples
///
/// ```
/// use std::fs::DirBuilder;
///
/// let mut builder = DirBuilder::new();
/// builder.recursive(true);
/// ```
#[stable(feature = "dir_builder", since = "1.6.0")]
pub fn recursive(&mut self, recursive: bool) -> &mut Self {
self.recursive = recursive;
self
}
/// Creates the specified directory with the options configured in this
/// builder.
///
/// It is considered an error if the directory already exists unless
/// recursive mode is enabled.
///
/// # Examples
///
/// ```no_run
/// use std::fs::{self, DirBuilder};
///
/// let path = "/tmp/foo/bar/baz";
/// DirBuilder::new()
/// .recursive(true)
/// .create(path).unwrap();
///
/// assert!(fs::metadata(path).unwrap().is_dir());
/// ```
#[stable(feature = "dir_builder", since = "1.6.0")]
pub fn create<P: AsRef<Path>>(&self, path: P) -> io::Result<()> {
self._create(path.as_ref())
}
fn _create(&self, path: &Path) -> io::Result<()> {
if self.recursive { self.create_dir_all(path) } else { self.inner.mkdir(path) }
}
fn create_dir_all(&self, path: &Path) -> io::Result<()> {
if path == Path::new("") {
return Ok(());
}
match self.inner.mkdir(path) {
Ok(()) => return Ok(()),
Err(ref e) if e.kind() == io::ErrorKind::NotFound => {}
Err(_) if path.is_dir() => return Ok(()),
Err(e) => return Err(e),
}
match path.parent() {
Some(p) => self.create_dir_all(p)?,
None => {
return Err(io::Error::new(io::ErrorKind::Other, "failed to create whole tree"));
}
}
match self.inner.mkdir(path) {
Ok(()) => Ok(()),
Err(_) if path.is_dir() => Ok(()),
Err(e) => Err(e),
}
}
}
impl AsInnerMut<fs_imp::DirBuilder> for DirBuilder {
fn as_inner_mut(&mut self) -> &mut fs_imp::DirBuilder {
&mut self.inner
}
}
#[cfg(all(test, not(any(target_os = "cloudabi", target_os = "emscripten", target_env = "sgx"))))]
mod tests {
use crate::io::prelude::*;
use crate::fs::{self, File, OpenOptions};
use crate::io::{ErrorKind, SeekFrom};
use crate::path::Path;
use crate::str;
use crate::sys_common::io::test::{tmpdir, TempDir};
use crate::thread;
use rand::{rngs::StdRng, RngCore, SeedableRng};
#[cfg(unix)]
use crate::os::unix::fs::symlink as symlink_dir;
#[cfg(unix)]
use crate::os::unix::fs::symlink as symlink_file;
#[cfg(unix)]
use crate::os::unix::fs::symlink as symlink_junction;
#[cfg(windows)]
use crate::os::windows::fs::{symlink_dir, symlink_file};
#[cfg(windows)]
use crate::sys::fs::symlink_junction;
macro_rules! check {
($e:expr) => {
match $e {
Ok(t) => t,
Err(e) => panic!("{} failed with: {}", stringify!($e), e),
}
};
}
#[cfg(windows)]
macro_rules! error {
($e:expr, $s:expr) => {
match $e {
Ok(_) => panic!("Unexpected success. Should've been: {:?}", $s),
Err(ref err) => assert!(
err.raw_os_error() == Some($s),
format!("`{}` did not have a code of `{}`", err, $s)
),
}
};
}
#[cfg(unix)]
macro_rules! error {
($e:expr, $s:expr) => {
error_contains!($e, $s)
};
}
macro_rules! error_contains {
($e:expr, $s:expr) => {
match $e {
Ok(_) => panic!("Unexpected success. Should've been: {:?}", $s),
Err(ref err) => assert!(
err.to_string().contains($s),
format!("`{}` did not contain `{}`", err, $s)
),
}
};
}
// Several test fail on windows if the user does not have permission to
// create symlinks (the `SeCreateSymbolicLinkPrivilege`). Instead of
// disabling these test on Windows, use this function to test whether we
// have permission, and return otherwise. This way, we still don't run these
// tests most of the time, but at least we do if the user has the right
// permissions.
pub fn got_symlink_permission(tmpdir: &TempDir) -> bool {
if cfg!(unix) {
return true;
}
let link = tmpdir.join("some_hopefully_unique_link_name");
match symlink_file(r"nonexisting_target", link) {
Ok(_) => true,
// ERROR_PRIVILEGE_NOT_HELD = 1314
Err(ref err) if err.raw_os_error() == Some(1314) => false,
Err(_) => true,
}
}
#[test]
fn file_test_io_smoke_test() {
let message = "it's alright. have a good time";
let tmpdir = tmpdir();
let filename = &tmpdir.join("file_rt_io_file_test.txt");
{
let mut write_stream = check!(File::create(filename));
check!(write_stream.write(message.as_bytes()));
}
{
let mut read_stream = check!(File::open(filename));
let mut read_buf = [0; 1028];
let read_str = match check!(read_stream.read(&mut read_buf)) {
0 => panic!("shouldn't happen"),
n => str::from_utf8(&read_buf[..n]).unwrap().to_string(),
};
assert_eq!(read_str, message);
}
check!(fs::remove_file(filename));
}
#[test]
fn invalid_path_raises() {
let tmpdir = tmpdir();
let filename = &tmpdir.join("file_that_does_not_exist.txt");
let result = File::open(filename);
#[cfg(all(unix, not(target_os = "vxworks")))]
error!(result, "No such file or directory");
#[cfg(target_os = "vxworks")]
error!(result, "no such file or directory");
#[cfg(windows)]
error!(result, 2); // ERROR_FILE_NOT_FOUND
}
#[test]
fn file_test_iounlinking_invalid_path_should_raise_condition() {
let tmpdir = tmpdir();
let filename = &tmpdir.join("file_another_file_that_does_not_exist.txt");
let result = fs::remove_file(filename);
#[cfg(all(unix, not(target_os = "vxworks")))]
error!(result, "No such file or directory");
#[cfg(target_os = "vxworks")]
error!(result, "no such file or directory");
#[cfg(windows)]
error!(result, 2); // ERROR_FILE_NOT_FOUND
}
#[test]
fn file_test_io_non_positional_read() {
let message: &str = "ten-four";
let mut read_mem = [0; 8];
let tmpdir = tmpdir();
let filename = &tmpdir.join("file_rt_io_file_test_positional.txt");
{
let mut rw_stream = check!(File::create(filename));
check!(rw_stream.write(message.as_bytes()));
}
{
let mut read_stream = check!(File::open(filename));
{
let read_buf = &mut read_mem[0..4];
check!(read_stream.read(read_buf));
}
{
let read_buf = &mut read_mem[4..8];
check!(read_stream.read(read_buf));
}
}
check!(fs::remove_file(filename));
let read_str = str::from_utf8(&read_mem).unwrap();
assert_eq!(read_str, message);
}
#[test]
fn file_test_io_seek_and_tell_smoke_test() {
let message = "ten-four";
let mut read_mem = [0; 4];
let set_cursor = 4 as u64;
let tell_pos_pre_read;
let tell_pos_post_read;
let tmpdir = tmpdir();
let filename = &tmpdir.join("file_rt_io_file_test_seeking.txt");
{
let mut rw_stream = check!(File::create(filename));
check!(rw_stream.write(message.as_bytes()));
}
{
let mut read_stream = check!(File::open(filename));
check!(read_stream.seek(SeekFrom::Start(set_cursor)));
tell_pos_pre_read = check!(read_stream.seek(SeekFrom::Current(0)));
check!(read_stream.read(&mut read_mem));
tell_pos_post_read = check!(read_stream.seek(SeekFrom::Current(0)));
}
check!(fs::remove_file(filename));
let read_str = str::from_utf8(&read_mem).unwrap();
assert_eq!(read_str, &message[4..8]);
assert_eq!(tell_pos_pre_read, set_cursor);
assert_eq!(tell_pos_post_read, message.len() as u64);
}
#[test]
fn file_test_io_seek_and_write() {
let initial_msg = "food-is-yummy";
let overwrite_msg = "-the-bar!!";
let final_msg = "foo-the-bar!!";
let seek_idx = 3;
let mut read_mem = [0; 13];
let tmpdir = tmpdir();
let filename = &tmpdir.join("file_rt_io_file_test_seek_and_write.txt");
{
let mut rw_stream = check!(File::create(filename));
check!(rw_stream.write(initial_msg.as_bytes()));
check!(rw_stream.seek(SeekFrom::Start(seek_idx)));
check!(rw_stream.write(overwrite_msg.as_bytes()));
}
{
let mut read_stream = check!(File::open(filename));
check!(read_stream.read(&mut read_mem));
}
check!(fs::remove_file(filename));
let read_str = str::from_utf8(&read_mem).unwrap();
assert!(read_str == final_msg);
}
#[test]
fn file_test_io_seek_shakedown() {
// 01234567890123
let initial_msg = "qwer-asdf-zxcv";
let chunk_one: &str = "qwer";
let chunk_two: &str = "asdf";
let chunk_three: &str = "zxcv";
let mut read_mem = [0; 4];
let tmpdir = tmpdir();
let filename = &tmpdir.join("file_rt_io_file_test_seek_shakedown.txt");
{
let mut rw_stream = check!(File::create(filename));
check!(rw_stream.write(initial_msg.as_bytes()));
}
{
let mut read_stream = check!(File::open(filename));
check!(read_stream.seek(SeekFrom::End(-4)));
check!(read_stream.read(&mut read_mem));
assert_eq!(str::from_utf8(&read_mem).unwrap(), chunk_three);
check!(read_stream.seek(SeekFrom::Current(-9)));
check!(read_stream.read(&mut read_mem));
assert_eq!(str::from_utf8(&read_mem).unwrap(), chunk_two);
check!(read_stream.seek(SeekFrom::Start(0)));
check!(read_stream.read(&mut read_mem));
assert_eq!(str::from_utf8(&read_mem).unwrap(), chunk_one);
}
check!(fs::remove_file(filename));
}
#[test]
fn file_test_io_eof() {
let tmpdir = tmpdir();
let filename = tmpdir.join("file_rt_io_file_test_eof.txt");
let mut buf = [0; 256];
{
let oo = OpenOptions::new().create_new(true).write(true).read(true).clone();
let mut rw = check!(oo.open(&filename));
assert_eq!(check!(rw.read(&mut buf)), 0);
assert_eq!(check!(rw.read(&mut buf)), 0);
}
check!(fs::remove_file(&filename));
}
#[test]
#[cfg(unix)]
fn file_test_io_read_write_at() {
use crate::os::unix::fs::FileExt;
let tmpdir = tmpdir();
let filename = tmpdir.join("file_rt_io_file_test_read_write_at.txt");
let mut buf = [0; 256];
let write1 = "asdf";
let write2 = "qwer-";
let write3 = "-zxcv";
let content = "qwer-asdf-zxcv";
{
let oo = OpenOptions::new().create_new(true).write(true).read(true).clone();
let mut rw = check!(oo.open(&filename));
assert_eq!(check!(rw.write_at(write1.as_bytes(), 5)), write1.len());
assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 0);
assert_eq!(check!(rw.read_at(&mut buf, 5)), write1.len());
assert_eq!(str::from_utf8(&buf[..write1.len()]), Ok(write1));
assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 0);
assert_eq!(check!(rw.read_at(&mut buf[..write2.len()], 0)), write2.len());
assert_eq!(str::from_utf8(&buf[..write2.len()]), Ok("\0\0\0\0\0"));
assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 0);
assert_eq!(check!(rw.write(write2.as_bytes())), write2.len());
assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 5);
assert_eq!(check!(rw.read(&mut buf)), write1.len());
assert_eq!(str::from_utf8(&buf[..write1.len()]), Ok(write1));
assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 9);
assert_eq!(check!(rw.read_at(&mut buf[..write2.len()], 0)), write2.len());
assert_eq!(str::from_utf8(&buf[..write2.len()]), Ok(write2));
assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 9);
assert_eq!(check!(rw.write_at(write3.as_bytes(), 9)), write3.len());
assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 9);
}
{
let mut read = check!(File::open(&filename));
assert_eq!(check!(read.read_at(&mut buf, 0)), content.len());
assert_eq!(str::from_utf8(&buf[..content.len()]), Ok(content));
assert_eq!(check!(read.seek(SeekFrom::Current(0))), 0);
assert_eq!(check!(read.seek(SeekFrom::End(-5))), 9);
assert_eq!(check!(read.read_at(&mut buf, 0)), content.len());
assert_eq!(str::from_utf8(&buf[..content.len()]), Ok(content));
assert_eq!(check!(read.seek(SeekFrom::Current(0))), 9);
assert_eq!(check!(read.read(&mut buf)), write3.len());
assert_eq!(str::from_utf8(&buf[..write3.len()]), Ok(write3));
assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
assert_eq!(check!(read.read_at(&mut buf, 0)), content.len());
assert_eq!(str::from_utf8(&buf[..content.len()]), Ok(content));
assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
assert_eq!(check!(read.read_at(&mut buf, 14)), 0);
assert_eq!(check!(read.read_at(&mut buf, 15)), 0);
assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
}
check!(fs::remove_file(&filename));
}
#[test]
#[cfg(unix)]
fn set_get_unix_permissions() {
use crate::os::unix::fs::PermissionsExt;
let tmpdir = tmpdir();
let filename = &tmpdir.join("set_get_unix_permissions");
check!(fs::create_dir(filename));
let mask = 0o7777;
check!(fs::set_permissions(filename, fs::Permissions::from_mode(0)));
let metadata0 = check!(fs::metadata(filename));
assert_eq!(mask & metadata0.permissions().mode(), 0);
check!(fs::set_permissions(filename, fs::Permissions::from_mode(0o1777)));
let metadata1 = check!(fs::metadata(filename));
#[cfg(all(unix, not(target_os = "vxworks")))]
assert_eq!(mask & metadata1.permissions().mode(), 0o1777);
#[cfg(target_os = "vxworks")]
assert_eq!(mask & metadata1.permissions().mode(), 0o0777);
}
#[test]
#[cfg(windows)]
fn file_test_io_seek_read_write() {
use crate::os::windows::fs::FileExt;
let tmpdir = tmpdir();
let filename = tmpdir.join("file_rt_io_file_test_seek_read_write.txt");
let mut buf = [0; 256];
let write1 = "asdf";
let write2 = "qwer-";
let write3 = "-zxcv";
let content = "qwer-asdf-zxcv";
{
let oo = OpenOptions::new().create_new(true).write(true).read(true).clone();
let mut rw = check!(oo.open(&filename));
assert_eq!(check!(rw.seek_write(write1.as_bytes(), 5)), write1.len());
assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 9);
assert_eq!(check!(rw.seek_read(&mut buf, 5)), write1.len());
assert_eq!(str::from_utf8(&buf[..write1.len()]), Ok(write1));
assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 9);
assert_eq!(check!(rw.seek(SeekFrom::Start(0))), 0);
assert_eq!(check!(rw.write(write2.as_bytes())), write2.len());
assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 5);
assert_eq!(check!(rw.read(&mut buf)), write1.len());
assert_eq!(str::from_utf8(&buf[..write1.len()]), Ok(write1));
assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 9);
assert_eq!(check!(rw.seek_read(&mut buf[..write2.len()], 0)), write2.len());
assert_eq!(str::from_utf8(&buf[..write2.len()]), Ok(write2));
assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 5);
assert_eq!(check!(rw.seek_write(write3.as_bytes(), 9)), write3.len());
assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 14);
}
{
let mut read = check!(File::open(&filename));
assert_eq!(check!(read.seek_read(&mut buf, 0)), content.len());
assert_eq!(str::from_utf8(&buf[..content.len()]), Ok(content));
assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
assert_eq!(check!(read.seek(SeekFrom::End(-5))), 9);
assert_eq!(check!(read.seek_read(&mut buf, 0)), content.len());
assert_eq!(str::from_utf8(&buf[..content.len()]), Ok(content));
assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
assert_eq!(check!(read.seek(SeekFrom::End(-5))), 9);
assert_eq!(check!(read.read(&mut buf)), write3.len());
assert_eq!(str::from_utf8(&buf[..write3.len()]), Ok(write3));
assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
assert_eq!(check!(read.seek_read(&mut buf, 0)), content.len());
assert_eq!(str::from_utf8(&buf[..content.len()]), Ok(content));
assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
assert_eq!(check!(read.seek_read(&mut buf, 14)), 0);
assert_eq!(check!(read.seek_read(&mut buf, 15)), 0);
}
check!(fs::remove_file(&filename));
}
#[test]
fn file_test_stat_is_correct_on_is_file() {
let tmpdir = tmpdir();
let filename = &tmpdir.join("file_stat_correct_on_is_file.txt");
{
let mut opts = OpenOptions::new();
let mut fs = check!(opts.read(true).write(true).create(true).open(filename));
let msg = "hw";
fs.write(msg.as_bytes()).unwrap();
let fstat_res = check!(fs.metadata());
assert!(fstat_res.is_file());
}
let stat_res_fn = check!(fs::metadata(filename));
assert!(stat_res_fn.is_file());
let stat_res_meth = check!(filename.metadata());
assert!(stat_res_meth.is_file());
check!(fs::remove_file(filename));
}
#[test]
fn file_test_stat_is_correct_on_is_dir() {
let tmpdir = tmpdir();
let filename = &tmpdir.join("file_stat_correct_on_is_dir");
check!(fs::create_dir(filename));
let stat_res_fn = check!(fs::metadata(filename));
assert!(stat_res_fn.is_dir());
let stat_res_meth = check!(filename.metadata());
assert!(stat_res_meth.is_dir());
check!(fs::remove_dir(filename));
}
#[test]
fn file_test_fileinfo_false_when_checking_is_file_on_a_directory() {
let tmpdir = tmpdir();
let dir = &tmpdir.join("fileinfo_false_on_dir");
check!(fs::create_dir(dir));
assert!(!dir.is_file());
check!(fs::remove_dir(dir));
}
#[test]
fn file_test_fileinfo_check_exists_before_and_after_file_creation() {
let tmpdir = tmpdir();
let file = &tmpdir.join("fileinfo_check_exists_b_and_a.txt");
check!(check!(File::create(file)).write(b"foo"));
assert!(file.exists());
check!(fs::remove_file(file));
assert!(!file.exists());
}
#[test]
fn file_test_directoryinfo_check_exists_before_and_after_mkdir() {
let tmpdir = tmpdir();
let dir = &tmpdir.join("before_and_after_dir");
assert!(!dir.exists());
check!(fs::create_dir(dir));
assert!(dir.exists());
assert!(dir.is_dir());
check!(fs::remove_dir(dir));
assert!(!dir.exists());
}
#[test]
fn file_test_directoryinfo_readdir() {
let tmpdir = tmpdir();
let dir = &tmpdir.join("di_readdir");
check!(fs::create_dir(dir));
let prefix = "foo";
for n in 0..3 {
let f = dir.join(&format!("{}.txt", n));
let mut w = check!(File::create(&f));
let msg_str = format!("{}{}", prefix, n.to_string());
let msg = msg_str.as_bytes();
check!(w.write(msg));
}
let files = check!(fs::read_dir(dir));
let mut mem = [0; 4];
for f in files {
let f = f.unwrap().path();
{
let n = f.file_stem().unwrap();
check!(check!(File::open(&f)).read(&mut mem));
let read_str = str::from_utf8(&mem).unwrap();
let expected = format!("{}{}", prefix, n.to_str().unwrap());
assert_eq!(expected, read_str);
}
check!(fs::remove_file(&f));
}
check!(fs::remove_dir(dir));
}
#[test]
fn file_create_new_already_exists_error() {
let tmpdir = tmpdir();
let file = &tmpdir.join("file_create_new_error_exists");
check!(fs::File::create(file));
let e = fs::OpenOptions::new().write(true).create_new(true).open(file).unwrap_err();
assert_eq!(e.kind(), ErrorKind::AlreadyExists);
}
#[test]
fn mkdir_path_already_exists_error() {
let tmpdir = tmpdir();
let dir = &tmpdir.join("mkdir_error_twice");
check!(fs::create_dir(dir));
let e = fs::create_dir(dir).unwrap_err();
assert_eq!(e.kind(), ErrorKind::AlreadyExists);
}
#[test]
fn recursive_mkdir() {
let tmpdir = tmpdir();
let dir = tmpdir.join("d1/d2");
check!(fs::create_dir_all(&dir));
assert!(dir.is_dir())
}
#[test]
fn recursive_mkdir_failure() {
let tmpdir = tmpdir();
let dir = tmpdir.join("d1");
let file = dir.join("f1");
check!(fs::create_dir_all(&dir));
check!(File::create(&file));
let result = fs::create_dir_all(&file);
assert!(result.is_err());
}
#[test]
fn concurrent_recursive_mkdir() {
for _ in 0..100 {
let dir = tmpdir();
let mut dir = dir.join("a");
for _ in 0..40 {
dir = dir.join("a");
}
let mut join = vec![];
for _ in 0..8 {
let dir = dir.clone();
join.push(thread::spawn(move || {
check!(fs::create_dir_all(&dir));
}))
}
// No `Display` on result of `join()`
join.drain(..).map(|join| join.join().unwrap()).count();
}
}
#[test]
fn recursive_mkdir_slash() {
check!(fs::create_dir_all(Path::new("/")));
}
#[test]
fn recursive_mkdir_dot() {
check!(fs::create_dir_all(Path::new(".")));
}
#[test]
fn recursive_mkdir_empty() {
check!(fs::create_dir_all(Path::new("")));
}
#[test]
fn recursive_rmdir() {
let tmpdir = tmpdir();
let d1 = tmpdir.join("d1");
let dt = d1.join("t");
let dtt = dt.join("t");
let d2 = tmpdir.join("d2");
let canary = d2.join("do_not_delete");
check!(fs::create_dir_all(&dtt));
check!(fs::create_dir_all(&d2));
check!(check!(File::create(&canary)).write(b"foo"));
check!(symlink_junction(&