Repository navigation
Expand file tree
/
Copy pathcrt_fd.rs
More file actions
414 lines (356 loc) · 9.65 KB
/
Copy pathcrt_fd.rs
File metadata and controls
414 lines (356 loc) · 9.65 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
//! A module implementing an io type backed by the C runtime's file descriptors, i.e. what's
//! returned from libc::open, even on windows.
use alloc::fmt;
use core::cmp;
use std::{ffi, io};
#[cfg(unix)]
use std::os::fd::AsFd;
#[cfg(not(windows))]
use std::os::fd::{AsRawFd, BorrowedFd, FromRawFd, IntoRawFd, OwnedFd, RawFd};
#[cfg(windows)]
use std::os::windows::io::BorrowedHandle;
mod c {
pub(super) use libc::*;
#[cfg(windows)]
pub(super) use libc::commit as fsync;
#[cfg(windows)]
unsafe extern "C" {
#[link_name = "_chsize_s"]
pub(super) fn ftruncate(fd: i32, len: i64) -> i32;
}
}
// this is basically what CPython has for Py_off_t; windows uses long long
// for offsets, other platforms just use off_t
pub type Offset = cfg_select! {
windows => c::c_longlong,
_ => c::off_t,
};
pub type Raw = cfg_select! {
windows => i32,
_ => RawFd,
};
#[inline]
fn cvt<I: num_traits::PrimInt>(ret: I) -> io::Result<I> {
if ret < I::zero() {
// CRT functions set errno, not GetLastError(), so use errno_io_error
Err(crate::os::errno_io_error())
} else {
Ok(ret)
}
}
fn cvt_fd(ret: Raw) -> io::Result<Owned> {
cvt(ret).map(|fd| unsafe { Owned::from_raw(fd) })
}
const MAX_RW: usize = if cfg!(any(windows, target_vendor = "apple")) {
i32::MAX as usize
} else {
isize::MAX as usize
};
#[cfg(not(windows))]
type OwnedInner = OwnedFd;
#[cfg(not(windows))]
type BorrowedInner<'fd> = BorrowedFd<'fd>;
#[cfg(windows)]
mod win {
use super::*;
use core::marker::PhantomData;
use core::mem::ManuallyDrop;
#[repr(transparent)]
pub(super) struct OwnedInner(i32);
impl OwnedInner {
#[inline]
pub unsafe fn from_raw_fd(fd: Raw) -> Self {
Self(fd)
}
#[inline]
pub fn as_raw_fd(&self) -> Raw {
self.0
}
#[inline]
pub fn into_raw_fd(self) -> Raw {
let me = ManuallyDrop::new(self);
me.0
}
}
impl Drop for OwnedInner {
#[inline]
fn drop(&mut self) {
let _ = _close(self.0);
}
}
#[derive(Copy, Clone)]
#[repr(transparent)]
pub(super) struct BorrowedInner<'fd> {
fd: Raw,
_marker: PhantomData<&'fd Owned>,
}
impl BorrowedInner<'_> {
#[inline]
pub const unsafe fn borrow_raw(fd: Raw) -> Self {
Self {
fd,
_marker: PhantomData,
}
}
#[inline]
pub fn as_raw_fd(&self) -> Raw {
self.fd
}
}
}
#[cfg(windows)]
use self::win::{BorrowedInner, OwnedInner};
#[repr(transparent)]
pub struct Owned {
inner: OwnedInner,
}
impl fmt::Debug for Owned {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_tuple("crt_fd::Owned")
.field(&self.as_raw())
.finish()
}
}
#[derive(Copy, Clone)]
#[repr(transparent)]
pub struct Borrowed<'fd> {
inner: BorrowedInner<'fd>,
}
impl<'fd> PartialEq for Borrowed<'fd> {
fn eq(&self, other: &Self) -> bool {
self.as_raw() == other.as_raw()
}
}
impl<'fd> Eq for Borrowed<'fd> {}
impl fmt::Debug for Borrowed<'_> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_tuple("crt_fd::Borrowed")
.field(&self.as_raw())
.finish()
}
}
impl Owned {
/// Create a `crt_fd::Owned` from a raw file descriptor.
///
/// # Safety
///
/// `fd` must be a valid file descriptor.
#[inline]
pub unsafe fn from_raw(fd: Raw) -> Self {
let inner = unsafe { OwnedInner::from_raw_fd(fd) };
Self { inner }
}
/// Create a `crt_fd::Owned` from a raw file descriptor.
///
/// Returns an error if `fd` is -1.
///
/// # Safety
///
/// `fd` must be a valid file descriptor.
#[inline]
pub unsafe fn try_from_raw(fd: Raw) -> io::Result<Self> {
if fd == -1 {
Err(ebadf())
} else {
Ok(unsafe { Self::from_raw(fd) })
}
}
#[inline]
pub fn borrow(&self) -> Borrowed<'_> {
unsafe { Borrowed::borrow_raw(self.as_raw()) }
}
#[inline]
pub fn as_raw(&self) -> Raw {
self.inner.as_raw_fd()
}
#[inline]
pub fn into_raw(self) -> Raw {
self.inner.into_raw_fd()
}
pub fn leak<'fd>(self) -> Borrowed<'fd> {
unsafe { Borrowed::borrow_raw(self.into_raw()) }
}
}
#[cfg(unix)]
impl From<Owned> for OwnedFd {
fn from(fd: Owned) -> Self {
fd.inner
}
}
#[cfg(unix)]
impl From<OwnedFd> for Owned {
fn from(fd: OwnedFd) -> Self {
Self { inner: fd }
}
}
#[cfg(unix)]
impl AsFd for Owned {
fn as_fd(&self) -> BorrowedFd<'_> {
self.inner.as_fd()
}
}
#[cfg(unix)]
impl AsRawFd for Owned {
fn as_raw_fd(&self) -> RawFd {
self.as_raw()
}
}
#[cfg(unix)]
impl FromRawFd for Owned {
unsafe fn from_raw_fd(fd: RawFd) -> Self {
unsafe { Self::from_raw(fd) }
}
}
#[cfg(unix)]
impl IntoRawFd for Owned {
fn into_raw_fd(self) -> RawFd {
self.into_raw()
}
}
impl<'fd> Borrowed<'fd> {
/// Create a `crt_fd::Borrowed` from a raw file descriptor.
///
/// # Safety
///
/// `fd` must be a valid file descriptor.
#[inline]
pub const unsafe fn borrow_raw(fd: Raw) -> Self {
let inner = unsafe { BorrowedInner::borrow_raw(fd) };
Self { inner }
}
/// Create a `crt_fd::Borrowed` from a raw file descriptor.
///
/// Returns an error if `fd` is -1.
///
/// # Safety
///
/// `fd` must be a valid file descriptor.
#[inline]
pub unsafe fn try_borrow_raw(fd: Raw) -> io::Result<Self> {
if fd == -1 {
Err(ebadf())
} else {
Ok(unsafe { Self::borrow_raw(fd) })
}
}
#[inline]
pub fn as_raw(self) -> Raw {
self.inner.as_raw_fd()
}
}
#[cfg(unix)]
impl<'fd> From<Borrowed<'fd>> for BorrowedFd<'fd> {
fn from(fd: Borrowed<'fd>) -> Self {
fd.inner
}
}
#[cfg(unix)]
impl<'fd> From<BorrowedFd<'fd>> for Borrowed<'fd> {
fn from(fd: BorrowedFd<'fd>) -> Self {
Self { inner: fd }
}
}
#[cfg(unix)]
impl AsFd for Borrowed<'_> {
fn as_fd(&self) -> BorrowedFd<'_> {
self.inner.as_fd()
}
}
#[cfg(unix)]
impl AsRawFd for Borrowed<'_> {
fn as_raw_fd(&self) -> RawFd {
self.as_raw()
}
}
#[inline]
fn ebadf() -> io::Error {
io::Error::from_raw_os_error(c::EBADF)
}
pub fn open(path: &ffi::CStr, flags: i32, mode: i32) -> io::Result<Owned> {
cvt_fd(unsafe { c::open(path.as_ptr(), flags, mode) })
}
#[cfg(windows)]
pub fn wopen(path: &widestring::WideCStr, flags: i32, mode: i32) -> io::Result<Owned> {
cvt_fd(unsafe { suppress_iph!(c::wopen(path.as_ptr(), flags, mode)) })
}
#[cfg(all(any(unix, target_os = "wasi"), not(target_os = "redox")))]
pub fn openat(dir: Borrowed<'_>, path: &ffi::CStr, flags: i32, mode: i32) -> io::Result<Owned> {
cvt_fd(unsafe { c::openat(dir.as_raw(), path.as_ptr(), flags, mode) })
}
pub fn fsync(fd: Borrowed<'_>) -> io::Result<()> {
cvt(unsafe { suppress_iph!(c::fsync(fd.as_raw())) })?;
Ok(())
}
fn _close(fd: Raw) -> io::Result<()> {
cvt(unsafe { suppress_iph!(c::close(fd)) })?;
Ok(())
}
pub fn close(fd: Owned) -> io::Result<()> {
_close(fd.into_raw())
}
pub fn ftruncate(fd: Borrowed<'_>, len: Offset) -> io::Result<()> {
let ret = unsafe { suppress_iph!(c::ftruncate(fd.as_raw(), len)) };
// On Windows, _chsize_s returns 0 on success, or a positive error code (errno value) on failure.
// On other platforms, ftruncate returns 0 on success, or -1 on failure with errno set.
cfg_select! {
windows => {
if ret != 0 {
// _chsize_s returns errno directly, convert to Windows error code
let winerror = crate::os::errno_to_winerror(ret);
return Err(io::Error::from_raw_os_error(winerror));
}
}
_ => cvt(ret)?,
};
Ok(())
}
#[cfg(windows)]
pub fn as_handle(fd: Borrowed<'_>) -> io::Result<BorrowedHandle<'_>> {
use windows_sys::Win32::Foundation::{HANDLE, INVALID_HANDLE_VALUE};
unsafe extern "C" {
fn _get_osfhandle(fd: Borrowed<'_>) -> c::intptr_t;
}
let handle = unsafe { suppress_iph!(_get_osfhandle(fd)) };
if handle as HANDLE == INVALID_HANDLE_VALUE {
// _get_osfhandle is a CRT function that sets errno, not GetLastError()
Err(crate::os::errno_io_error())
} else {
Ok(unsafe { BorrowedHandle::borrow_raw(handle as _) })
}
}
fn _write(fd: Raw, buf: &[u8]) -> io::Result<usize> {
let count = cmp::min(buf.len(), MAX_RW);
let n = cvt(unsafe { suppress_iph!(c::write(fd, buf.as_ptr() as _, count as _)) })?;
Ok(n as usize)
}
fn _read(fd: Raw, buf: &mut [u8]) -> io::Result<usize> {
let count = cmp::min(buf.len(), MAX_RW);
let n = cvt(unsafe { suppress_iph!(libc::read(fd, buf.as_mut_ptr() as _, count as _)) })?;
Ok(n as usize)
}
pub fn write(fd: Borrowed<'_>, buf: &[u8]) -> io::Result<usize> {
_write(fd.as_raw(), buf)
}
pub fn read(fd: Borrowed<'_>, buf: &mut [u8]) -> io::Result<usize> {
_read(fd.as_raw(), buf)
}
macro_rules! impl_rw {
($t:ty) => {
impl io::Write for $t {
fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
_write(self.as_raw(), buf)
}
#[inline]
fn flush(&mut self) -> io::Result<()> {
Ok(())
}
}
impl io::Read for $t {
fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
_read(self.as_raw(), buf)
}
}
};
}
impl_rw!(Owned);
impl_rw!(Borrowed<'_>);