Auto merge of #30872 - pitdicker:expand_open_options, r=alexcrichton

Tracking issue: #30014

This implements the RFC and makes a few other changes.
I have added a few extra tests, and made the Windows and
Unix code as similar as possible.

Part of the RFC mentions the unstable OpenOptionsExt trait
on Windows (see #27720). I have added a few extra methods
to future-proof it for CreateFile2.
This commit is contained in:
bors 2016-01-20 17:19:21 +00:00
commit 292af75f8d
6 changed files with 471 additions and 168 deletions

View File

@ -375,7 +375,7 @@ impl<'a> Seek for &'a File {
}
impl OpenOptions {
/// Creates a blank net set of options ready for configuration.
/// Creates a blank new set of options ready for configuration.
///
/// All options are initially set to `false`.
///
@ -384,7 +384,8 @@ impl OpenOptions {
/// ```no_run
/// use std::fs::OpenOptions;
///
/// let file = OpenOptions::new().open("foo.txt");
/// let mut options = OpenOptions::new();
/// let file = options.read(true).open("foo.txt");
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn new() -> OpenOptions {
@ -413,6 +414,9 @@ impl OpenOptions {
/// This option, when true, will indicate that the file should be
/// `write`-able if opened.
///
/// If a file already exist, any write calls on the file will overwrite its
/// contents, without truncating it.
///
/// # Examples
///
/// ```no_run
@ -429,13 +433,30 @@ impl OpenOptions {
///
/// 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 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 the the file in one operation. This
/// can be done by concatenating strings before passing them to `write()`,
/// or using a buffered writer (with a more than adequately sized buffer)
/// 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.
///
/// # Examples
///
/// ```no_run
/// use std::fs::OpenOptions;
///
/// let file = OpenOptions::new().write(true).append(true).open("foo.txt");
/// let file = OpenOptions::new().append(true).open("foo.txt");
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
pub fn append(&mut self, append: bool) -> &mut OpenOptions {
@ -447,6 +468,8 @@ impl OpenOptions {
/// 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
@ -464,18 +487,54 @@ impl OpenOptions {
/// This option indicates whether a new file will be created if the file
/// does not yet already exist.
///
/// The file must be opened with write or append access in order to create
/// a new file.
///
/// # Examples
///
/// ```no_run
/// use std::fs::OpenOptions;
///
/// let file = OpenOptions::new().create(true).open("foo.txt");
/// 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 OpenOptions {
self.0.create(create); self
}
/// Sets the option to always create a new file.
///
/// This option indicates whether a new file will be created.
/// No file is allowed to exist at the target location, also no (dangling)
/// symlink.
///
/// This option is usefull because it as 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.
///
/// # Examples
///
/// ```no_run
/// #![feature(expand_open_options)]
/// use std::fs::OpenOptions;
///
/// let file = OpenOptions::new().write(true)
/// .create_new(true)
/// .open("foo.txt");
/// ```
#[unstable(feature = "expand_open_options",
reason = "recently added",
issue = "30014")]
pub fn create_new(&mut self, create_new: bool) -> &mut OpenOptions {
self.0.create_new(create_new); self
}
/// Opens a file at `path` with the options specified by `self`.
///
/// # Errors
@ -483,10 +542,13 @@ impl OpenOptions {
/// This function will return an error under a number of different
/// circumstances, to include but not limited to:
///
/// * Opening a file that does not exist with read access.
/// * Opening a file that does not exist without setting `create` or
/// `create_new`.
/// * Attempting to open a file with access that the user lacks
/// permissions for
/// * Filesystem-level errors (full disk, etc)
/// * Invalid combinations of open options (truncate without write access,
/// no access mode set, etc)
///
/// # Examples
///
@ -2098,61 +2160,114 @@ mod tests {
let mut r = OO::new(); r.read(true);
let mut w = OO::new(); w.write(true);
let mut rw = OO::new(); rw.write(true).read(true);
let mut rw = OO::new(); rw.read(true).write(true);
let mut a = OO::new(); a.append(true);
let mut ra = OO::new(); ra.read(true).append(true);
match r.open(&tmpdir.join("a")) {
Ok(..) => panic!(), Err(..) => {}
}
let invalid_options = if cfg!(windows) { "The parameter is incorrect" }
else { "Invalid argument" };
// Perform each one twice to make sure that it succeeds the second time
// (where the file exists)
check!(c(&w).create(true).open(&tmpdir.join("b")));
assert!(tmpdir.join("b").exists());
check!(c(&w).create(true).open(&tmpdir.join("b")));
check!(w.open(&tmpdir.join("b")));
// Test various combinations of creation modes and access modes.
//
// Allowed:
// creation mode | read | write | read-write | append | read-append |
// :-----------------------|:-----:|:-----:|:----------:|:------:|:-----------:|
// not set (open existing) | X | X | X | X | X |
// create | | X | X | X | X |
// truncate | | X | X | | |
// create and truncate | | X | X | | |
// create_new | | X | X | X | X |
//
// tested in reverse order, so 'create_new' creates the file, and 'open existing' opens it.
// write-only
check!(c(&w).create_new(true).open(&tmpdir.join("a")));
check!(c(&w).create(true).truncate(true).open(&tmpdir.join("a")));
check!(c(&w).truncate(true).open(&tmpdir.join("a")));
check!(c(&w).create(true).open(&tmpdir.join("a")));
check!(c(&w).open(&tmpdir.join("a")));
// read-only
error!(c(&r).create_new(true).open(&tmpdir.join("b")), invalid_options);
error!(c(&r).create(true).truncate(true).open(&tmpdir.join("b")), invalid_options);
error!(c(&r).truncate(true).open(&tmpdir.join("b")), invalid_options);
error!(c(&r).create(true).open(&tmpdir.join("b")), invalid_options);
check!(c(&r).open(&tmpdir.join("a"))); // try opening the file created with write_only
// read-write
check!(c(&rw).create_new(true).open(&tmpdir.join("c")));
check!(c(&rw).create(true).truncate(true).open(&tmpdir.join("c")));
check!(c(&rw).truncate(true).open(&tmpdir.join("c")));
check!(c(&rw).create(true).open(&tmpdir.join("c")));
assert!(tmpdir.join("c").exists());
check!(c(&rw).create(true).open(&tmpdir.join("c")));
check!(rw.open(&tmpdir.join("c")));
check!(c(&rw).open(&tmpdir.join("c")));
check!(c(&w).append(true).create(true).open(&tmpdir.join("d")));
assert!(tmpdir.join("d").exists());
check!(c(&w).append(true).create(true).open(&tmpdir.join("d")));
check!(c(&w).append(true).open(&tmpdir.join("d")));
// append
check!(c(&a).create_new(true).open(&tmpdir.join("d")));
error!(c(&a).create(true).truncate(true).open(&tmpdir.join("d")), invalid_options);
error!(c(&a).truncate(true).open(&tmpdir.join("d")), invalid_options);
check!(c(&a).create(true).open(&tmpdir.join("d")));
check!(c(&a).open(&tmpdir.join("d")));
check!(c(&rw).append(true).create(true).open(&tmpdir.join("e")));
assert!(tmpdir.join("e").exists());
check!(c(&rw).append(true).create(true).open(&tmpdir.join("e")));
check!(c(&rw).append(true).open(&tmpdir.join("e")));
// read-append
check!(c(&ra).create_new(true).open(&tmpdir.join("e")));
error!(c(&ra).create(true).truncate(true).open(&tmpdir.join("e")), invalid_options);
error!(c(&ra).truncate(true).open(&tmpdir.join("e")), invalid_options);
check!(c(&ra).create(true).open(&tmpdir.join("e")));
check!(c(&ra).open(&tmpdir.join("e")));
check!(c(&w).truncate(true).create(true).open(&tmpdir.join("f")));
assert!(tmpdir.join("f").exists());
check!(c(&w).truncate(true).create(true).open(&tmpdir.join("f")));
check!(c(&w).truncate(true).open(&tmpdir.join("f")));
// Test opening a file without setting an access mode
let mut blank = OO::new();
error!(blank.create(true).open(&tmpdir.join("f")), invalid_options);
check!(c(&rw).truncate(true).create(true).open(&tmpdir.join("g")));
assert!(tmpdir.join("g").exists());
check!(c(&rw).truncate(true).create(true).open(&tmpdir.join("g")));
check!(c(&rw).truncate(true).open(&tmpdir.join("g")));
// Test write works
check!(check!(File::create(&tmpdir.join("h"))).write("foobar".as_bytes()));
check!(check!(File::create(&tmpdir.join("h"))).write("foo".as_bytes()));
// Test write fails for read-only
check!(r.open(&tmpdir.join("h")));
{
let mut f = check!(r.open(&tmpdir.join("h")));
assert!(f.write("wut".as_bytes()).is_err());
}
// Test write overwrites
{
let mut f = check!(c(&w).open(&tmpdir.join("h")));
check!(f.write("baz".as_bytes()));
}
{
let mut f = check!(c(&r).open(&tmpdir.join("h")));
let mut b = vec![0; 6];
check!(f.read(&mut b));
assert_eq!(b, "bazbar".as_bytes());
}
// Test truncate works
{
let mut f = check!(c(&w).truncate(true).open(&tmpdir.join("h")));
check!(f.write("foo".as_bytes()));
}
assert_eq!(check!(fs::metadata(&tmpdir.join("h"))).len(), 3);
// Test append works
assert_eq!(check!(fs::metadata(&tmpdir.join("h"))).len(), 3);
{
let mut f = check!(c(&w).append(true).open(&tmpdir.join("h")));
let mut f = check!(c(&a).open(&tmpdir.join("h")));
check!(f.write("bar".as_bytes()));
}
assert_eq!(check!(fs::metadata(&tmpdir.join("h"))).len(), 6);
// Test .append(true) equals .write(true).append(true)
{
let mut f = check!(c(&w).truncate(true).open(&tmpdir.join("h")));
check!(f.write("bar".as_bytes()));
let mut f = check!(c(&w).append(true).open(&tmpdir.join("h")));
check!(f.write("baz".as_bytes()));
}
assert_eq!(check!(fs::metadata(&tmpdir.join("h"))).len(), 3);
assert_eq!(check!(fs::metadata(&tmpdir.join("h"))).len(), 9);
}
#[test]
fn _assert_send_sync() {
fn _assert_send_sync<T: Send + Sync>() {}
_assert_send_sync::<OpenOptions>();
}
#[test]

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@ -118,8 +118,38 @@ pub trait OpenOptionsExt {
///
/// If a new file is created as part of a `File::open_opts` call then this
/// specified `mode` will be used as the permission bits for the new file.
/// If no `mode` is set, the default of `0o666` will be used.
/// The operating system masks out bits with the systems `umask`, to produce
/// the final permissions.
#[stable(feature = "fs_ext", since = "1.1.0")]
fn mode(&mut self, mode: raw::mode_t) -> &mut Self;
/// Pass custom flags to the `flags` agument of `open`.
///
/// The bits that define the access mode are masked out with `O_ACCMODE`, to
/// ensure they do not interfere with the access mode set by Rusts options.
///
/// Custom flags can only set flags, not remove flags set by Rusts options.
/// This options overwrites any previously set custom flags.
///
/// # Examples
///
/// ```rust,ignore
/// extern crate libc;
/// use std::fs::OpenOptions;
/// use std::os::unix::fs::OpenOptionsExt;
///
/// let mut options = OpenOptions::new();
/// options.write(true);
/// if cfg!(unix) {
/// options.custom_flags(libc::O_NOFOLLOW);
/// }
/// let file = options.open("foo.txt");
/// ```
#[unstable(feature = "expand_open_options",
reason = "recently added",
issue = "30014")]
fn custom_flags(&mut self, flags: i32) -> &mut Self;
}
#[stable(feature = "fs_ext", since = "1.1.0")]
@ -127,6 +157,10 @@ impl OpenOptionsExt for OpenOptions {
fn mode(&mut self, mode: raw::mode_t) -> &mut OpenOptions {
self.as_inner_mut().mode(mode); self
}
fn custom_flags(&mut self, flags: i32) -> &mut OpenOptions {
self.as_inner_mut().custom_flags(flags); self
}
}
// Hm, why are there casts here to the returned type, shouldn't the types always
@ -281,4 +315,3 @@ impl DirBuilderExt for fs::DirBuilder {
self
}
}

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@ -50,9 +50,15 @@ pub struct DirEntry {
#[derive(Clone)]
pub struct OpenOptions {
flags: c_int,
// generic
read: bool,
write: bool,
append: bool,
truncate: bool,
create: bool,
create_new: bool,
// system-specific
custom_flags: i32,
mode: mode_t,
}
@ -233,44 +239,61 @@ impl DirEntry {
impl OpenOptions {
pub fn new() -> OpenOptions {
OpenOptions {
flags: libc::O_CLOEXEC,
// generic
read: false,
write: false,
append: false,
truncate: false,
create: false,
create_new: false,
// system-specific
custom_flags: 0,
mode: 0o666,
}
}
pub fn read(&mut self, read: bool) {
self.read = read;
}
pub fn read(&mut self, read: bool) { self.read = read; }
pub fn write(&mut self, write: bool) { self.write = write; }
pub fn append(&mut self, append: bool) { self.append = append; }
pub fn truncate(&mut self, truncate: bool) { self.truncate = truncate; }
pub fn create(&mut self, create: bool) { self.create = create; }
pub fn create_new(&mut self, create_new: bool) { self.create_new = create_new; }
pub fn write(&mut self, write: bool) {
self.write = write;
}
pub fn custom_flags(&mut self, flags: i32) { self.custom_flags = flags; }
pub fn mode(&mut self, mode: raw::mode_t) { self.mode = mode as mode_t; }
pub fn append(&mut self, append: bool) {
self.flag(libc::O_APPEND, append);
}
pub fn truncate(&mut self, truncate: bool) {
self.flag(libc::O_TRUNC, truncate);
}
pub fn create(&mut self, create: bool) {
self.flag(libc::O_CREAT, create);
}
pub fn mode(&mut self, mode: raw::mode_t) {
self.mode = mode as mode_t;
}
fn flag(&mut self, bit: c_int, on: bool) {
if on {
self.flags |= bit;
} else {
self.flags &= !bit;
fn get_access_mode(&self) -> io::Result<c_int> {
match (self.read, self.write, self.append) {
(true, false, false) => Ok(libc::O_RDONLY),
(false, true, false) => Ok(libc::O_WRONLY),
(true, true, false) => Ok(libc::O_RDWR),
(false, _, true) => Ok(libc::O_WRONLY | libc::O_APPEND),
(true, _, true) => Ok(libc::O_RDWR | libc::O_APPEND),
(false, false, false) => Err(Error::from_raw_os_error(libc::EINVAL)),
}
}
fn get_creation_mode(&self) -> io::Result<c_int> {
match (self.write, self.append) {
(true, false) => {}
(false, false) =>
if self.truncate || self.create || self.create_new {
return Err(Error::from_raw_os_error(libc::EINVAL));
},
(_, true) =>
if self.truncate && !self.create_new {
return Err(Error::from_raw_os_error(libc::EINVAL));
},
}
Ok(match (self.create, self.truncate, self.create_new) {
(false, false, false) => 0,
(true, false, false) => libc::O_CREAT,
(false, true, false) => libc::O_TRUNC,
(true, true, false) => libc::O_CREAT | libc::O_TRUNC,
(_, _, true) => libc::O_CREAT | libc::O_EXCL,
})
}
}
impl File {
@ -280,12 +303,10 @@ impl File {
}
pub fn open_c(path: &CStr, opts: &OpenOptions) -> io::Result<File> {
let flags = opts.flags | match (opts.read, opts.write) {
(true, true) => libc::O_RDWR,
(false, true) => libc::O_WRONLY,
(true, false) |
(false, false) => libc::O_RDONLY,
};
let flags = libc::O_CLOEXEC |
try!(opts.get_access_mode()) |
try!(opts.get_creation_mode()) |
(opts.custom_flags as c_int & !libc::O_ACCMODE);
let fd = try!(cvt_r(|| unsafe {
libc::open(path.as_ptr(), flags, opts.mode as c_int)
}));

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@ -93,16 +93,30 @@ pub const CREATE_NEW: DWORD = 1;
pub const OPEN_ALWAYS: DWORD = 4;
pub const OPEN_EXISTING: DWORD = 3;
pub const TRUNCATE_EXISTING: DWORD = 5;
pub const FILE_APPEND_DATA: DWORD = 0x00000004;
pub const FILE_READ_DATA: DWORD = 0x00000001;
pub const FILE_WRITE_DATA: DWORD = 0x00000002;
pub const STANDARD_RIGHTS_READ: DWORD = 0x20000;
pub const STANDARD_RIGHTS_WRITE: DWORD = 0x20000;
pub const FILE_WRITE_EA: DWORD = 0x00000010;
pub const FILE_APPEND_DATA: DWORD = 0x00000004;
pub const FILE_READ_EA: DWORD = 0x00000008;
pub const SYNCHRONIZE: DWORD = 0x00100000;
pub const FILE_WRITE_ATTRIBUTES: DWORD = 0x00000100;
pub const FILE_WRITE_EA: DWORD = 0x00000010;
pub const FILE_EXECUTE: DWORD = 0x00000020;
pub const FILE_READ_ATTRIBUTES: DWORD = 0x00000080;
pub const FILE_WRITE_ATTRIBUTES: DWORD = 0x00000100;
pub const DELETE: DWORD = 0x00008000;
pub const READ_CONTROL: DWORD = 0x00020000;
pub const WRITE_DAC: DWORD = 0x00040000;
pub const WRITE_OWNER: DWORD = 0x00080000;
pub const SYNCHRONIZE: DWORD = 0x00100000;
pub const GENERIC_READ: DWORD = 0x80000000;
pub const GENERIC_WRITE: DWORD = 0x40000000;
pub const GENERIC_EXECUTE: DWORD = 0x20000000;
pub const GENERIC_ALL: DWORD = 0x10000000;
pub const STANDARD_RIGHTS_READ: DWORD = READ_CONTROL;
pub const STANDARD_RIGHTS_WRITE: DWORD = READ_CONTROL;
pub const STANDARD_RIGHTS_EXECUTE: DWORD = READ_CONTROL;
pub const FILE_GENERIC_READ: DWORD = STANDARD_RIGHTS_READ | FILE_READ_DATA |
FILE_READ_ATTRIBUTES |
FILE_READ_EA |
@ -113,6 +127,14 @@ pub const FILE_GENERIC_WRITE: DWORD = STANDARD_RIGHTS_WRITE | FILE_WRITE_DATA |
FILE_APPEND_DATA |
SYNCHRONIZE;
pub const SECURITY_ANONYMOUS: DWORD = 0 << 16;
pub const SECURITY_IDENTIFICATION: DWORD = 1 << 16;
pub const SECURITY_IMPERSONATION: DWORD = 2 << 16;
pub const SECURITY_DELEGATION: DWORD = 3 << 16;
pub const SECURITY_CONTEXT_TRACKING: DWORD = 0x00040000;
pub const SECURITY_EFFECTIVE_ONLY: DWORD = 0x00080000;
pub const SECURITY_SQOS_PRESENT: DWORD = 0x00100000;
#[repr(C)]
#[derive(Copy)]
pub struct WIN32_FIND_DATAW {

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@ -25,45 +25,131 @@ use sys_common::{AsInnerMut, AsInner};
pub trait OpenOptionsExt {
/// Overrides the `dwDesiredAccess` argument to the call to `CreateFile`
/// with the specified value.
fn desired_access(&mut self, access: u32) -> &mut Self;
/// Overrides the `dwCreationDisposition` argument to the call to
/// `CreateFile` with the specified value.
///
/// This will override any values of the standard `create` flags, for
/// example.
fn creation_disposition(&mut self, val: u32) -> &mut Self;
/// Overrides the `dwFlagsAndAttributes` argument to the call to
/// `CreateFile` with the specified value.
/// This will override the `read`, `write`, and `append` flags on the
/// `OpenOptions` structure. This method provides fine-grained control over
/// the permissions to read, write and append data, attributes (like hidden
/// and system) and extended attributes.
///
/// This will override any values of the standard flags on the
/// `OpenOptions` structure.
fn flags_and_attributes(&mut self, val: u32) -> &mut Self;
/// # Examples
///
/// ```no_run
/// #![feature(open_options_ext)]
/// use std::fs::OpenOptions;
/// use std::os::windows::fs::OpenOptionsExt;
///
/// // Open without read and write permission, for example if you only need
/// // to call `stat()` on the file
/// let file = OpenOptions::new().access_mode(0).open("foo.txt");
/// ```
fn access_mode(&mut self, access: u32) -> &mut Self;
/// Overrides the `dwShareMode` argument to the call to `CreateFile` with
/// the specified value.
///
/// This will override any values of the standard flags on the
/// `OpenOptions` structure.
/// By default `share_mode` is set to
/// `FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE`. Specifying
/// less permissions denies others to read from, write to and/or delete the
/// file while it is open.
///
/// # Examples
///
/// ```no_run
/// #![feature(open_options_ext)]
/// use std::fs::OpenOptions;
/// use std::os::windows::fs::OpenOptionsExt;
///
/// // Do not allow others to read or modify this file while we have it open
/// // for writing
/// let file = OpenOptions::new().write(true)
/// .share_mode(0)
/// .open("foo.txt");
/// ```
fn share_mode(&mut self, val: u32) -> &mut Self;
/// Sets extra flags for the `dwFileFlags` argument to the call to
/// `CreateFile2` (or combines it with `attributes` and `security_qos_flags`
/// to set the `dwFlagsAndAttributes` for `CreateFile`).
///
/// Custom flags can only set flags, not remove flags set by Rusts options.
/// This options overwrites any previously set custom flags.
///
/// # Examples
///
/// ```rust,ignore
/// extern crate winapi;
/// use std::fs::OpenOptions;
/// use std::os::windows::fs::OpenOptionsExt;
///
/// let mut options = OpenOptions::new();
/// options.create(true).write(true);
/// if cfg!(windows) {
/// options.custom_flags(winapi::FILE_FLAG_DELETE_ON_CLOSE);
/// }
/// let file = options.open("foo.txt");
/// ```
#[unstable(feature = "expand_open_options",
reason = "recently added",
issue = "30014")]
fn custom_flags(&mut self, flags: u32) -> &mut Self;
/// Sets the `dwFileAttributes` argument to the call to `CreateFile2` to
/// the specified value (or combines it with `custom_flags` and
/// `security_qos_flags` to set the `dwFlagsAndAttributes` for
/// `CreateFile`).
///
/// If a _new_ file is created because it does not yet exist and
///`.create(true)` or `.create_new(true)` are specified, the new file is
/// given the attributes declared with `.attributes()`.
///
/// If an _existing_ file is opened with `.create(true).truncate(true)`, its
/// existing attributes are preserved and combined with the ones declared
/// with `.attributes()`.
///
/// In all other cases the attributes get ignored.
///
/// # Examples
///
/// ```rust,ignore
/// #![feature(open_options_ext)]
/// extern crate winapi;
/// use std::fs::OpenOptions;
/// use std::os::windows::fs::OpenOptionsExt;
///
/// let file = OpenOptions::new().write(true).create(true)
/// .attributes(winapi::FILE_ATTRIBUTE_HIDDEN)
/// .open("foo.txt");
/// ```
fn attributes(&mut self, val: u32) -> &mut Self;
/// Sets the `dwSecurityQosFlags` argument to the call to `CreateFile2` to
/// the specified value (or combines it with `custom_flags` and `attributes`
/// to set the `dwFlagsAndAttributes` for `CreateFile`).
fn security_qos_flags(&mut self, flags: u32) -> &mut OpenOptions;
}
#[unstable(feature = "open_options_ext",
reason = "may require more thought/methods",
issue = "27720")]
impl OpenOptionsExt for OpenOptions {
fn desired_access(&mut self, access: u32) -> &mut OpenOptions {
self.as_inner_mut().desired_access(access); self
fn access_mode(&mut self, access: u32) -> &mut OpenOptions {
self.as_inner_mut().access_mode(access); self
}
fn creation_disposition(&mut self, access: u32) -> &mut OpenOptions {
self.as_inner_mut().creation_disposition(access); self
fn share_mode(&mut self, share: u32) -> &mut OpenOptions {
self.as_inner_mut().share_mode(share); self
}
fn flags_and_attributes(&mut self, access: u32) -> &mut OpenOptions {
self.as_inner_mut().flags_and_attributes(access); self
fn custom_flags(&mut self, flags: u32) -> &mut OpenOptions {
self.as_inner_mut().custom_flags(flags); self
}
fn share_mode(&mut self, access: u32) -> &mut OpenOptions {
self.as_inner_mut().share_mode(access); self
fn attributes(&mut self, attributes: u32) -> &mut OpenOptions {
self.as_inner_mut().attributes(attributes); self
}
fn security_qos_flags(&mut self, flags: u32) -> &mut OpenOptions {
self.as_inner_mut().security_qos_flags(flags); self
}
}

View File

@ -54,18 +54,22 @@ pub struct DirEntry {
data: c::WIN32_FIND_DATAW,
}
#[derive(Clone, Default)]
#[derive(Clone)]
pub struct OpenOptions {
create: bool,
append: bool,
// generic
read: bool,
write: bool,
append: bool,
truncate: bool,
desired_access: Option<c::DWORD>,
share_mode: Option<c::DWORD>,
creation_disposition: Option<c::DWORD>,
flags_and_attributes: Option<c::DWORD>,
security_attributes: usize, // *mut T doesn't have a Default impl
create: bool,
create_new: bool,
// system-specific
custom_flags: u32,
access_mode: Option<c::DWORD>,
attributes: c::DWORD,
share_mode: c::DWORD,
security_qos_flags: c::DWORD,
security_attributes: usize, // FIXME: should be a reference
}
#[derive(Clone, PartialEq, Eq, Debug)]
@ -151,68 +155,86 @@ impl DirEntry {
}
impl OpenOptions {
pub fn new() -> OpenOptions { Default::default() }
pub fn new() -> OpenOptions {
OpenOptions {
// generic
read: false,
write: false,
append: false,
truncate: false,
create: false,
create_new: false,
// system-specific
custom_flags: 0,
access_mode: None,
share_mode: c::FILE_SHARE_READ | c::FILE_SHARE_WRITE | c::FILE_SHARE_DELETE,
attributes: 0,
security_qos_flags: 0,
security_attributes: 0,
}
}
pub fn read(&mut self, read: bool) { self.read = read; }
pub fn write(&mut self, write: bool) { self.write = write; }
pub fn append(&mut self, append: bool) { self.append = append; }
pub fn create(&mut self, create: bool) { self.create = create; }
pub fn truncate(&mut self, truncate: bool) { self.truncate = truncate; }
pub fn creation_disposition(&mut self, val: u32) {
self.creation_disposition = Some(val);
}
pub fn flags_and_attributes(&mut self, val: u32) {
self.flags_and_attributes = Some(val);
}
pub fn desired_access(&mut self, val: u32) {
self.desired_access = Some(val);
}
pub fn share_mode(&mut self, val: u32) {
self.share_mode = Some(val);
}
pub fn create(&mut self, create: bool) { self.create = create; }
pub fn create_new(&mut self, create_new: bool) { self.create_new = create_new; }
pub fn custom_flags(&mut self, flags: u32) { self.custom_flags = flags; }
pub fn access_mode(&mut self, access_mode: u32) { self.access_mode = Some(access_mode); }
pub fn share_mode(&mut self, share_mode: u32) { self.share_mode = share_mode; }
pub fn attributes(&mut self, attrs: u32) { self.attributes = attrs; }
pub fn security_qos_flags(&mut self, flags: u32) { self.security_qos_flags = flags; }
pub fn security_attributes(&mut self, attrs: c::LPSECURITY_ATTRIBUTES) {
self.security_attributes = attrs as usize;
}
fn get_desired_access(&self) -> c::DWORD {
self.desired_access.unwrap_or({
let mut base = if self.read {c::FILE_GENERIC_READ} else {0} |
if self.write {c::FILE_GENERIC_WRITE} else {0};
if self.append {
base &= !c::FILE_WRITE_DATA;
base |= c::FILE_APPEND_DATA;
}
base
})
fn get_access_mode(&self) -> io::Result<c::DWORD> {
const ERROR_INVALID_PARAMETER: i32 = 87;
match (self.read, self.write, self.append, self.access_mode) {
(_, _, _, Some(mode)) => Ok(mode),
(true, false, false, None) => Ok(c::GENERIC_READ),
(false, true, false, None) => Ok(c::GENERIC_WRITE),
(true, true, false, None) => Ok(c::GENERIC_READ | c::GENERIC_WRITE),
(false, _, true, None) => Ok(c::FILE_GENERIC_WRITE & !c::FILE_WRITE_DATA),
(true, _, true, None) => Ok(c::GENERIC_READ |
(c::FILE_GENERIC_WRITE & !c::FILE_WRITE_DATA)),
(false, false, false, None) => Err(Error::from_raw_os_error(ERROR_INVALID_PARAMETER)),
}
}
fn get_share_mode(&self) -> c::DWORD {
// libuv has a good comment about this, but the basic idea is that
// we try to emulate unix semantics by enabling all sharing by
// allowing things such as deleting a file while it's still open.
self.share_mode.unwrap_or(c::FILE_SHARE_READ |
c::FILE_SHARE_WRITE |
c::FILE_SHARE_DELETE)
}
fn get_creation_mode(&self) -> io::Result<c::DWORD> {
const ERROR_INVALID_PARAMETER: i32 = 87;
fn get_creation_disposition(&self) -> c::DWORD {
self.creation_disposition.unwrap_or({
match (self.create, self.truncate) {
(true, true) => c::CREATE_ALWAYS,
(true, false) => c::OPEN_ALWAYS,
(false, false) => c::OPEN_EXISTING,
(false, true) => {
if self.write && !self.append {
c::CREATE_ALWAYS
} else {
c::TRUNCATE_EXISTING
}
}
}
})
match (self.write, self.append) {
(true, false) => {}
(false, false) =>
if self.truncate || self.create || self.create_new {
return Err(Error::from_raw_os_error(ERROR_INVALID_PARAMETER));
},
(_, true) =>
if self.truncate && !self.create_new {
return Err(Error::from_raw_os_error(ERROR_INVALID_PARAMETER));
},
}
Ok(match (self.create, self.truncate, self.create_new) {
(false, false, false) => c::OPEN_EXISTING,
(true, false, false) => c::OPEN_ALWAYS,
(false, true, false) => c::TRUNCATE_EXISTING,
(true, true, false) => c::CREATE_ALWAYS,
(_, _, true) => c::CREATE_NEW,
})
}
fn get_flags_and_attributes(&self) -> c::DWORD {
self.flags_and_attributes.unwrap_or(c::FILE_ATTRIBUTE_NORMAL)
self.custom_flags |
self.attributes |
self.security_qos_flags |
if self.security_qos_flags != 0 { c::SECURITY_SQOS_PRESENT } else { 0 } |
if self.create_new { c::FILE_FLAG_OPEN_REPARSE_POINT } else { 0 }
}
}
@ -221,8 +243,8 @@ impl File {
let mut opts = OpenOptions::new();
opts.read(!write);
opts.write(write);
opts.flags_and_attributes(c::FILE_FLAG_OPEN_REPARSE_POINT |
c::FILE_FLAG_BACKUP_SEMANTICS);
opts.custom_flags(c::FILE_FLAG_OPEN_REPARSE_POINT |
c::FILE_FLAG_BACKUP_SEMANTICS);
File::open(path, &opts)
}
@ -230,10 +252,10 @@ impl File {
let path = try!(to_u16s(path));
let handle = unsafe {
c::CreateFileW(path.as_ptr(),
opts.get_desired_access(),
opts.get_share_mode(),
try!(opts.get_access_mode()),
opts.share_mode,
opts.security_attributes as *mut _,
opts.get_creation_disposition(),
try!(opts.get_creation_mode()),
opts.get_flags_and_attributes(),
ptr::null_mut())
};
@ -533,7 +555,10 @@ pub fn stat(p: &Path) -> io::Result<FileAttr> {
// metadata information is.
if attr.is_reparse_point() {
let mut opts = OpenOptions::new();
opts.flags_and_attributes(c::FILE_FLAG_BACKUP_SEMANTICS);
// No read or write permissions are necessary
opts.access_mode(0);
// This flag is so we can open directories too
opts.custom_flags(c::FILE_FLAG_BACKUP_SEMANTICS);
let file = try!(File::open(p, &opts));
file.file_attr()
} else {
@ -577,9 +602,10 @@ fn get_path(f: &File) -> io::Result<PathBuf> {
pub fn canonicalize(p: &Path) -> io::Result<PathBuf> {
let mut opts = OpenOptions::new();
opts.read(true);
// No read or write permissions are necessary
opts.access_mode(0);
// This flag is so we can open directories too
opts.flags_and_attributes(c::FILE_FLAG_BACKUP_SEMANTICS);
opts.custom_flags(c::FILE_FLAG_BACKUP_SEMANTICS);
let f = try!(File::open(p, &opts));
get_path(&f)
}