Skip to content

Commit

Permalink
auto merge of #13897 : aturon/rust/issue-6085, r=bjz
Browse files Browse the repository at this point in the history 
The `std::bitflags::bitflags!` macro did not provide support for
adding attributes to the generates structure, due to limitations in
the parser for macros. This patch works around the parser limitations
by requiring a `flags` keyword in the `bitflags!` invocations:

    bitflags!(
        #[deriving(Hash)]
        #[doc="Three flags"]
        flags Flags: u32 {
            FlagA       = 0x00000001,
            FlagB       = 0x00000010,
            FlagC       = 0x00000100
        }
    )

The intent of `std::bitflags` is to allow building type-safe wrappers
around C-style flags APIs. But in addition to construction these flags
from the Rust side, we need a way to convert them from the C
side. This patch adds a `from_bits` function, which is unsafe since
the bits in question may not represent a valid combination of flags.

Finally, this patch changes `std::io::FilePermissions` from an exposed
`u32` representation to a typesafe representation (that only allows valid
flag combinations) using the `std::bitflags`.

Closes #6085.
  • Loading branch information
@bors
bors committed May 6, 2014
2 parents 1f6db7f + 8d1d7d9 commit cf6857b
Show file tree
Hide file tree
Showing 7 changed files with 101 additions and 69 deletions.
8 changes: 5 additions & 3 deletions src/libnative/io/file_unix.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -335,7 +335,7 @@ pub fn open(path: &CString, fm: io::FileMode, fa: io::FileAccess)

pub fn mkdir(p: &CString, mode: io::FilePermission) -> IoResult<()> {
super::mkerr_libc(retry(|| unsafe {
libc::mkdir(p.with_ref(|p| p), mode as libc::mode_t)
libc::mkdir(p.with_ref(|p| p), mode.bits() as libc::mode_t)
}))
}

Expand Down Expand Up @@ -392,7 +392,7 @@ pub fn rename(old: &CString, new: &CString) -> IoResult<()> {

pub fn chmod(p: &CString, mode: io::FilePermission) -> IoResult<()> {
super::mkerr_libc(retry(|| unsafe {
libc::chmod(p.with_ref(|p| p), mode as libc::mode_t)
libc::chmod(p.with_ref(|p| p), mode.bits() as libc::mode_t)
}))
}

Expand Down Expand Up @@ -470,7 +470,9 @@ fn mkstat(stat: &libc::stat, path: &CString) -> io::FileStat {
path: Path::new(path),
size: stat.st_size as u64,
kind: kind,
perm: (stat.st_mode) as io::FilePermission & io::AllPermissions,
perm: unsafe {
io::FilePermission::from_bits(stat.st_mode as u32) & io::AllPermissions
},
created: mktime(stat.st_ctime as u64, stat.st_ctime_nsec as u64),
modified: mktime(stat.st_mtime as u64, stat.st_mtime_nsec as u64),
accessed: mktime(stat.st_atime as u64, stat.st_atime_nsec as u64),
Expand Down
6 changes: 4 additions & 2 deletions src/libnative/io/file_win32.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -392,7 +392,7 @@ pub fn rename(old: &CString, new: &CString) -> IoResult<()> {

pub fn chmod(p: &CString, mode: io::FilePermission) -> IoResult<()> {
super::mkerr_libc(as_utf16_p(p.as_str().unwrap(), |p| unsafe {
libc::wchmod(p, mode as libc::c_int)
libc::wchmod(p, mode.bits() as libc::c_int)
}))
}

Expand Down Expand Up @@ -471,7 +471,9 @@ fn mkstat(stat: &libc::stat, path: &CString) -> io::FileStat {
path: Path::new(path),
size: stat.st_size as u64,
kind: kind,
perm: (stat.st_mode) as io::FilePermission & io::AllPermissions,
perm: unsafe {
io::FilePermission::from_bits(stat.st_mode as u32) & io::AllPermissions
},
created: stat.st_ctime as u64,
modified: stat.st_mtime as u64,
accessed: stat.st_atime as u64,
Expand Down
4 changes: 3 additions & 1 deletion src/librustuv/file.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -283,7 +283,9 @@ impl FsRequest {
path: path,
size: stat.st_size as u64,
kind: kind,
perm: (stat.st_mode as io::FilePermission) & io::AllPermissions,
perm: unsafe {
io::FilePermission::from_bits(stat.st_mode as u32) & io::AllPermissions
},
created: to_msec(stat.st_birthtim),
modified: to_msec(stat.st_mtim),
accessed: to_msec(stat.st_atim),
Expand Down
4 changes: 2 additions & 2 deletions src/librustuv/uvio.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -224,7 +224,7 @@ impl IoFactory for UvIoFactory {
}
fn fs_mkdir(&mut self, path: &CString,
perm: io::FilePermission) -> Result<(), IoError> {
let r = FsRequest::mkdir(&self.loop_, path, perm as c_int);
let r = FsRequest::mkdir(&self.loop_, path, perm.bits() as c_int);
r.map_err(uv_error_to_io_error)
}
fn fs_rmdir(&mut self, path: &CString) -> Result<(), IoError> {
Expand All @@ -237,7 +237,7 @@ impl IoFactory for UvIoFactory {
}
fn fs_chmod(&mut self, path: &CString,
perm: io::FilePermission) -> Result<(), IoError> {
let r = FsRequest::chmod(&self.loop_, path, perm as c_int);
let r = FsRequest::chmod(&self.loop_, path, perm.bits() as c_int);
r.map_err(uv_error_to_io_error)
}
fn fs_readdir(&mut self, path: &CString, flags: c_int)
Expand Down
71 changes: 46 additions & 25 deletions src/libstd/bitflags.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -17,14 +17,16 @@
//! # Example
//!
//! ~~~rust
//! bitflags!(Flags: u32 {
//! FlagA = 0x00000001,
//! FlagB = 0x00000010,
//! FlagC = 0x00000100,
//! FlagABC = FlagA.bits
//! | FlagB.bits
//! | FlagC.bits
//! })
//! bitflags!(
//! flags Flags: u32 {
//! static FlagA = 0x00000001,
//! static FlagB = 0x00000010,
//! static FlagC = 0x00000100,
//! static FlagABC = FlagA.bits
//! | FlagB.bits
//! | FlagC.bits
//! }
//! )
//!
//! fn main() {
//! let e1 = FlagA | FlagC;
Expand All @@ -40,10 +42,12 @@
//! ~~~rust
//! use std::fmt;
//!
//! bitflags!(Flags: u32 {
//! FlagA = 0x00000001,
//! FlagB = 0x00000010
//! })
//! bitflags!(
//! flags Flags: u32 {
//! static FlagA = 0x00000001,
//! static FlagB = 0x00000010
//! }
//! )
//!
//! impl Flags {
//! pub fn clear(&mut self) {
Expand All @@ -66,10 +70,16 @@
//! }
//! ~~~
//!
//! # Attributes
//!
//! Attributes can be attached to the generated `struct` by placing them
//! before the `flags` keyword.
//!
//! # Derived traits
//!
//! The `Eq`, `TotalEq`, and `Clone` traits are automatically derived for the
//! `struct` using the `deriving` attribute.
//! The `Eq` and `Clone` traits are automatically derived for the `struct` using
//! the `deriving` attribute. Additional traits can be derived by providing an
//! explicit `deriving` attribute on `flags`.
//!
//! # Operators
//!
Expand All @@ -91,17 +101,20 @@
//! - `insert`: inserts the specified flags in-place
//! - `remove`: removes the specified flags in-place
#![macro_escape]

#[macro_export]
macro_rules! bitflags(
($BitFlags:ident: $T:ty {
$($Flag:ident = $value:expr),+
($(#[$attr:meta])* flags $BitFlags:ident: $T:ty {
$($(#[$Flag_attr:meta])* static $Flag:ident = $value:expr),+
}) => (
#[deriving(Eq, TotalEq, Clone)]
$(#[$attr])*
pub struct $BitFlags {
bits: $T,
}

$(pub static $Flag: $BitFlags = $BitFlags { bits: $value };)+
$($(#[$Flag_attr])* pub static $Flag: $BitFlags = $BitFlags { bits: $value };)+

impl $BitFlags {
/// Returns an empty set of flags.
Expand All @@ -114,6 +127,12 @@ macro_rules! bitflags(
self.bits
}

/// Convert from underlying bit representation. Unsafe because the
/// bits are not guaranteed to represent valid flags.
pub unsafe fn from_bits(bits: $T) -> $BitFlags {
$BitFlags { bits: bits }
}

/// Returns `true` if no flags are currently stored.
pub fn is_empty(&self) -> bool {
*self == $BitFlags::empty()
Expand Down Expand Up @@ -170,14 +189,16 @@ macro_rules! bitflags(
mod tests {
use ops::{BitOr, BitAnd, Sub};

bitflags!(Flags: u32 {
FlagA = 0x00000001,
FlagB = 0x00000010,
FlagC = 0x00000100,
FlagABC = FlagA.bits
| FlagB.bits
| FlagC.bits
})
bitflags!(
flags Flags: u32 {
static FlagA = 0x00000001,
static FlagB = 0x00000010,
static FlagC = 0x00000100,
static FlagABC = FlagA.bits
| FlagB.bits
| FlagC.bits
}
)

#[test]
fn test_bits(){
Expand Down
6 changes: 3 additions & 3 deletions src/libstd/io/fs.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1119,7 +1119,7 @@ mod test {
check!(File::create(&input));
check!(chmod(&input, io::UserRead));
check!(copy(&input, &out));
assert!(check!(out.stat()).perm & io::UserWrite == 0);
assert!(!check!(out.stat()).perm.intersects(io::UserWrite));

check!(chmod(&input, io::UserFile));
check!(chmod(&out, io::UserFile));
Expand Down Expand Up @@ -1193,9 +1193,9 @@ mod test {
let file = tmpdir.join("in.txt");

check!(File::create(&file));
assert!(check!(stat(&file)).perm & io::UserWrite == io::UserWrite);
assert!(check!(stat(&file)).perm.contains(io::UserWrite));
check!(chmod(&file, io::UserRead));
assert!(check!(stat(&file)).perm & io::UserWrite == 0);
assert!(!check!(stat(&file)).perm.contains(io::UserWrite));

match chmod(&tmpdir.join("foo"), io::UserRWX) {
Ok(..) => fail!("wanted a failure"),
Expand Down
71 changes: 38 additions & 33 deletions src/libstd/io/mod.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -224,6 +224,7 @@ use fmt;
use int;
use iter::Iterator;
use libc;
use ops::{BitOr, BitAnd, Sub};
use os;
use option::{Option, Some, None};
use path::Path;
Expand Down Expand Up @@ -1558,36 +1559,40 @@ pub struct UnstableFileStat {
pub gen: u64,
}

/// A set of permissions for a file or directory is represented by a set of
/// flags which are or'd together.
pub type FilePermission = u32;

// Each permission bit
pub static UserRead: FilePermission = 0x100;
pub static UserWrite: FilePermission = 0x080;
pub static UserExecute: FilePermission = 0x040;
pub static GroupRead: FilePermission = 0x020;
pub static GroupWrite: FilePermission = 0x010;
pub static GroupExecute: FilePermission = 0x008;
pub static OtherRead: FilePermission = 0x004;
pub static OtherWrite: FilePermission = 0x002;
pub static OtherExecute: FilePermission = 0x001;

// Common combinations of these bits
pub static UserRWX: FilePermission = UserRead | UserWrite | UserExecute;
pub static GroupRWX: FilePermission = GroupRead | GroupWrite | GroupExecute;
pub static OtherRWX: FilePermission = OtherRead | OtherWrite | OtherExecute;

/// A set of permissions for user owned files, this is equivalent to 0644 on
/// unix-like systems.
pub static UserFile: FilePermission = UserRead | UserWrite | GroupRead | OtherRead;
/// A set of permissions for user owned directories, this is equivalent to 0755
/// on unix-like systems.
pub static UserDir: FilePermission = UserRWX | GroupRead | GroupExecute |
OtherRead | OtherExecute;
/// A set of permissions for user owned executables, this is equivalent to 0755
/// on unix-like systems.
pub static UserExec: FilePermission = UserDir;

/// A mask for all possible permission bits
pub static AllPermissions: FilePermission = 0x1ff;
bitflags!(
#[doc="A set of permissions for a file or directory is represented
by a set of flags which are or'd together."]
#[deriving(Hash)]
#[deriving(Show)]
flags FilePermission: u32 {
static UserRead = 0o400,
static UserWrite = 0o200,
static UserExecute = 0o100,
static GroupRead = 0o040,
static GroupWrite = 0o020,
static GroupExecute = 0o010,
static OtherRead = 0o004,
static OtherWrite = 0o002,
static OtherExecute = 0o001,

static UserRWX = UserRead.bits | UserWrite.bits | UserExecute.bits,
static GroupRWX = GroupRead.bits | GroupWrite.bits | GroupExecute.bits,
static OtherRWX = OtherRead.bits | OtherWrite.bits | OtherExecute.bits,

#[doc="Permissions for user owned files, equivalent to 0644 on
unix-like systems."]
static UserFile = UserRead.bits | UserWrite.bits | GroupRead.bits | OtherRead.bits,

#[doc="Permissions for user owned directories, equivalent to 0755 on
unix-like systems."]
static UserDir = UserRWX.bits | GroupRead.bits | GroupExecute.bits |
OtherRead.bits | OtherExecute.bits,

#[doc="Permissions for user owned executables, equivalent to 0755
on unix-like systems."]
static UserExec = UserDir.bits,

#[doc="All possible permissions enabled."]
static AllPermissions = UserRWX.bits | GroupRWX.bits | OtherRWX.bits
}
)

0 comments on commit cf6857b

Please sign in to comment.