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-rw-r--r--ctr-std/src/sys/horizon/fd.rs265
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diff --git a/ctr-std/src/sys/horizon/fd.rs b/ctr-std/src/sys/horizon/fd.rs
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+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![unstable(reason = "not public", issue = "0", feature = "fd")]
+
+use cmp;
+use io::{self, Read};
+use libc::{self, c_int, c_void, ssize_t};
+use mem;
+use sync::atomic::{AtomicBool, Ordering};
+use sys::cvt;
+use sys_common::AsInner;
+
+#[derive(Debug)]
+pub struct FileDesc {
+ fd: c_int,
+}
+
+fn max_len() -> usize {
+ // The maximum read limit on most posix-like systems is `SSIZE_MAX`,
+ // with the man page quoting that if the count of bytes to read is
+ // greater than `SSIZE_MAX` the result is "unspecified".
+ //
+ // On macOS, however, apparently the 64-bit libc is either buggy or
+ // intentionally showing odd behavior by rejecting any read with a size
+ // larger than or equal to INT_MAX. To handle both of these the read
+ // size is capped on both platforms.
+ if cfg!(target_os = "macos") {
+ <c_int>::max_value() as usize - 1
+ } else {
+ <ssize_t>::max_value() as usize
+ }
+}
+
+impl FileDesc {
+ pub fn new(fd: c_int) -> FileDesc {
+ FileDesc { fd: fd }
+ }
+
+ pub fn raw(&self) -> c_int { self.fd }
+
+ /// Extracts the actual filedescriptor without closing it.
+ pub fn into_raw(self) -> c_int {
+ let fd = self.fd;
+ mem::forget(self);
+ fd
+ }
+
+ pub fn read(&self, buf: &mut [u8]) -> io::Result<usize> {
+ let ret = cvt(unsafe {
+ libc::read(self.fd,
+ buf.as_mut_ptr() as *mut c_void,
+ cmp::min(buf.len(), max_len()))
+ })?;
+ Ok(ret as usize)
+ }
+
+ pub fn read_to_end(&self, buf: &mut Vec<u8>) -> io::Result<usize> {
+ let mut me = self;
+ (&mut me).read_to_end(buf)
+ }
+
+ pub fn read_at(&self, buf: &mut [u8], offset: u64) -> io::Result<usize> {
+ #[cfg(target_os = "android")]
+ use super::android::cvt_pread64;
+
+ #[cfg(target_os = "emscripten")]
+ unsafe fn cvt_pread64(fd: c_int, buf: *mut c_void, count: usize, offset: i64)
+ -> io::Result<isize>
+ {
+ use convert::TryInto;
+ use libc::pread64;
+ // pread64 on emscripten actually takes a 32 bit offset
+ if let Ok(o) = offset.try_into() {
+ cvt(pread64(fd, buf, count, o))
+ } else {
+ Err(io::Error::new(io::ErrorKind::InvalidInput,
+ "cannot pread >2GB"))
+ }
+ }
+
+ #[cfg(not(any(target_os = "android", target_os = "emscripten")))]
+ unsafe fn cvt_pread64(fd: c_int, buf: *mut c_void, count: usize, offset: i64)
+ -> io::Result<isize>
+ {
+ #[cfg(target_os = "linux")]
+ use libc::pread64;
+ #[cfg(not(target_os = "linux"))]
+ use libc::pread as pread64;
+ cvt(pread64(fd, buf, count, offset))
+ }
+
+ unsafe {
+ cvt_pread64(self.fd,
+ buf.as_mut_ptr() as *mut c_void,
+ cmp::min(buf.len(), max_len()),
+ offset as i64)
+ .map(|n| n as usize)
+ }
+ }
+
+ pub fn write(&self, buf: &[u8]) -> io::Result<usize> {
+ let ret = cvt(unsafe {
+ libc::write(self.fd,
+ buf.as_ptr() as *const c_void,
+ cmp::min(buf.len(), max_len()))
+ })?;
+ Ok(ret as usize)
+ }
+
+ pub fn write_at(&self, buf: &[u8], offset: u64) -> io::Result<usize> {
+ #[cfg(target_os = "android")]
+ use super::android::cvt_pwrite64;
+
+ #[cfg(target_os = "emscripten")]
+ unsafe fn cvt_pwrite64(fd: c_int, buf: *const c_void, count: usize, offset: i64)
+ -> io::Result<isize>
+ {
+ use convert::TryInto;
+ use libc::pwrite64;
+ // pwrite64 on emscripten actually takes a 32 bit offset
+ if let Ok(o) = offset.try_into() {
+ cvt(pwrite64(fd, buf, count, o))
+ } else {
+ Err(io::Error::new(io::ErrorKind::InvalidInput,
+ "cannot pwrite >2GB"))
+ }
+ }
+
+ #[cfg(not(any(target_os = "android", target_os = "emscripten")))]
+ unsafe fn cvt_pwrite64(fd: c_int, buf: *const c_void, count: usize, offset: i64)
+ -> io::Result<isize>
+ {
+ #[cfg(target_os = "linux")]
+ use libc::pwrite64;
+ #[cfg(not(target_os = "linux"))]
+ use libc::pwrite as pwrite64;
+ cvt(pwrite64(fd, buf, count, offset))
+ }
+
+ unsafe {
+ cvt_pwrite64(self.fd,
+ buf.as_ptr() as *const c_void,
+ cmp::min(buf.len(), max_len()),
+ offset as i64)
+ .map(|n| n as usize)
+ }
+ }
+
+ // We don't have fork/exec on the 3DS, so this shouldn't need to do anything
+ #[cfg(target_os = "horizon")]
+ pub fn set_cloexec(&self) -> io::Result<()> {
+ Ok(())
+ }
+
+ #[cfg(target_os = "linux")]
+ pub fn get_cloexec(&self) -> io::Result<bool> {
+ unsafe {
+ Ok((cvt(libc::fcntl(self.fd, libc::F_GETFD))? & libc::FD_CLOEXEC) != 0)
+ }
+ }
+
+ #[cfg(target_os = "linux")]
+ pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> {
+ unsafe {
+ let v = nonblocking as c_int;
+ cvt(libc::ioctl(self.fd, libc::FIONBIO, &v))?;
+ Ok(())
+ }
+ }
+
+ #[cfg(not(target_os = "linux"))]
+ pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> {
+ unsafe {
+ let previous = cvt(libc::fcntl(self.fd, libc::F_GETFL))?;
+ let new = if nonblocking {
+ previous | libc::O_NONBLOCK
+ } else {
+ previous & !libc::O_NONBLOCK
+ };
+ if new != previous {
+ cvt(libc::fcntl(self.fd, libc::F_SETFL, new))?;
+ }
+ Ok(())
+ }
+ }
+
+ pub fn duplicate(&self) -> io::Result<FileDesc> {
+ // We want to atomically duplicate this file descriptor and set the
+ // CLOEXEC flag, and currently that's done via F_DUPFD_CLOEXEC. This
+ // flag, however, isn't supported on older Linux kernels (earlier than
+ // 2.6.24).
+ //
+ // To detect this and ensure that CLOEXEC is still set, we
+ // follow a strategy similar to musl [1] where if passing
+ // F_DUPFD_CLOEXEC causes `fcntl` to return EINVAL it means it's not
+ // supported (the third parameter, 0, is always valid), so we stop
+ // trying that.
+ //
+ // Also note that Android doesn't have F_DUPFD_CLOEXEC, but get it to
+ // resolve so we at least compile this.
+ //
+ // [1]: http://comments.gmane.org/gmane.linux.lib.musl.general/2963
+ #[cfg(any(target_os = "android", target_os = "haiku"))]
+ use libc::F_DUPFD as F_DUPFD_CLOEXEC;
+ #[cfg(not(any(target_os = "android", target_os="haiku")))]
+ use libc::F_DUPFD_CLOEXEC;
+
+ let make_filedesc = |fd| {
+ let fd = FileDesc::new(fd);
+ fd.set_cloexec()?;
+ Ok(fd)
+ };
+ static TRY_CLOEXEC: AtomicBool =
+ AtomicBool::new(!cfg!(target_os = "android"));
+ let fd = self.raw();
+ if TRY_CLOEXEC.load(Ordering::Relaxed) {
+ match cvt(unsafe { libc::fcntl(fd, F_DUPFD_CLOEXEC, 0) }) {
+ // We *still* call the `set_cloexec` method as apparently some
+ // linux kernel at some point stopped setting CLOEXEC even
+ // though it reported doing so on F_DUPFD_CLOEXEC.
+ Ok(fd) => {
+ return Ok(if cfg!(target_os = "linux") {
+ make_filedesc(fd)?
+ } else {
+ FileDesc::new(fd)
+ })
+ }
+ Err(ref e) if e.raw_os_error() == Some(libc::EINVAL) => {
+ TRY_CLOEXEC.store(false, Ordering::Relaxed);
+ }
+ Err(e) => return Err(e),
+ }
+ }
+ cvt(unsafe { libc::fcntl(fd, libc::F_DUPFD, 0) }).and_then(make_filedesc)
+ }
+}
+
+impl<'a> Read for &'a FileDesc {
+ fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+ (**self).read(buf)
+ }
+}
+
+impl AsInner<c_int> for FileDesc {
+ fn as_inner(&self) -> &c_int { &self.fd }
+}
+
+impl Drop for FileDesc {
+ fn drop(&mut self) {
+ // Note that errors are ignored when closing a file descriptor. The
+ // reason for this is that if an error occurs we don't actually know if
+ // the file descriptor was closed or not, and if we retried (for
+ // something like EINTR), we might close another valid file descriptor
+ // (opened after we closed ours.
+ let _ = unsafe { libc::close(self.fd) };
+ }
+}
generated by cgit v1.2.3 (git 2.25.1) at 2026-04-21 16:34:47 +0000