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-rw-r--r--vendor/miow-0.3.7/src/overlapped.rs92
1 files changed, 92 insertions, 0 deletions
diff --git a/vendor/miow-0.3.7/src/overlapped.rs b/vendor/miow-0.3.7/src/overlapped.rs
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+++ b/vendor/miow-0.3.7/src/overlapped.rs
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+use std::fmt;
+use std::io;
+use std::mem;
+use std::ptr;
+
+use winapi::shared::ntdef::{HANDLE, NULL};
+use winapi::um::minwinbase::*;
+use winapi::um::synchapi::*;
+
+/// A wrapper around `OVERLAPPED` to provide "rustic" accessors and
+/// initializers.
+pub struct Overlapped(OVERLAPPED);
+
+impl fmt::Debug for Overlapped {
+ fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+ write!(f, "OVERLAPPED")
+ }
+}
+
+unsafe impl Send for Overlapped {}
+unsafe impl Sync for Overlapped {}
+
+impl Overlapped {
+ /// Creates a new zeroed out instance of an overlapped I/O tracking state.
+ ///
+ /// This is suitable for passing to methods which will then later get
+ /// notified via an I/O Completion Port.
+ pub fn zero() -> Overlapped {
+ Overlapped(unsafe { mem::zeroed() })
+ }
+
+ /// Creates a new `Overlapped` with an initialized non-null `hEvent`. The caller is
+ /// responsible for calling `CloseHandle` on the `hEvent` field of the returned
+ /// `Overlapped`. The event is created with `bManualReset` set to `FALSE`, meaning after a
+ /// single thread waits on the event, it will be reset.
+ pub fn initialize_with_autoreset_event() -> io::Result<Overlapped> {
+ let event = unsafe { CreateEventW(ptr::null_mut(), 0i32, 0i32, ptr::null()) };
+ if event == NULL {
+ return Err(io::Error::last_os_error());
+ }
+ let mut overlapped = Self::zero();
+ overlapped.set_event(event);
+ Ok(overlapped)
+ }
+
+ /// Creates a new `Overlapped` function pointer from the underlying
+ /// `OVERLAPPED`, wrapping in the "rusty" wrapper for working with
+ /// accessors.
+ ///
+ /// # Unsafety
+ ///
+ /// This function doesn't validate `ptr` nor the lifetime of the returned
+ /// pointer at all, it's recommended to use this method with extreme
+ /// caution.
+ pub unsafe fn from_raw<'a>(ptr: *mut OVERLAPPED) -> &'a mut Overlapped {
+ &mut *(ptr as *mut Overlapped)
+ }
+
+ /// Gain access to the raw underlying data
+ pub fn raw(&self) -> *mut OVERLAPPED {
+ &self.0 as *const _ as *mut _
+ }
+
+ /// Sets the offset inside this overlapped structure.
+ ///
+ /// Note that for I/O operations in general this only has meaning for I/O
+ /// handles that are on a seeking device that supports the concept of an
+ /// offset.
+ pub fn set_offset(&mut self, offset: u64) {
+ let s = unsafe { self.0.u.s_mut() };
+ s.Offset = offset as u32;
+ s.OffsetHigh = (offset >> 32) as u32;
+ }
+
+ /// Reads the offset inside this overlapped structure.
+ pub fn offset(&self) -> u64 {
+ let s = unsafe { self.0.u.s() };
+ (s.Offset as u64) | ((s.OffsetHigh as u64) << 32)
+ }
+
+ /// Sets the `hEvent` field of this structure.
+ ///
+ /// The event specified can be null.
+ pub fn set_event(&mut self, event: HANDLE) {
+ self.0.hEvent = event;
+ }
+
+ /// Reads the `hEvent` field of this structure, may return null.
+ pub fn event(&self) -> HANDLE {
+ self.0.hEvent
+ }
+}