Store named pipe path instead of querying it again

The windows API for querying the named pipe path explicitly mentions that it shouldn't be used with pipes.
To avoid that, store the path of the pipe when binging it, and reuse that value.

Signed-off-by: Jorge Prendes <jorge.prendes@gmail.com>

Author: jprendes

src/asynchronous/transport/windows.rs

@@ -1,17 +1,13 @@
-use std::convert::TryFrom;
-use std::io::{Error as IoError, Result as IoResult};
-use std::mem::{replace, zeroed};
-use std::os::windows::ffi::OsStringExt as _;
+use std::io::Result as IoResult;
+use std::mem::replace;
 use std::time::Duration;
-use std::os::windows::io::AsRawHandle;
 
 use async_stream::stream;
 use tokio::net::windows::named_pipe::{
     ClientOptions, NamedPipeClient, NamedPipeServer, ServerOptions,
 };
 use tokio::time::sleep;
-use windows_sys::Win32::Foundation::{ERROR_MORE_DATA, ERROR_PIPE_BUSY};
-use windows_sys::Win32::Storage::FileSystem::*;
+use windows_sys::Win32::Foundation::ERROR_PIPE_BUSY;
 
 use super::{Listener, Socket};
 
@@ -20,7 +16,7 @@ impl Listener {
         let listener = ServerOptions::new()
             .first_pipe_instance(true)
             .create(addr.as_ref())?;
-        Self::try_from(listener)
+        Ok(Self::from((listener, addr)))
     }
 }
 
@@ -39,19 +35,18 @@ impl Socket {
     }
 }
 
-impl TryFrom<NamedPipeServer> for Listener {
-    type Error = IoError;
-    fn try_from(mut listener: NamedPipeServer) -> IoResult<Self> {
-        let name = get_pipe_name(&listener)?;
-        Ok(Self::new(stream! {
+impl<T: AsRef<str>> From<(NamedPipeServer, T)> for Listener {
+    fn from((mut listener, addr): (NamedPipeServer, T)) -> Self {
+        let addr = addr.as_ref().to_string();
+        Self::new(stream! {
             loop {
                 yield listener
                     .connect()
                     .await
-                    .and_then(|_| ServerOptions::new().create(&name))
+                    .and_then(|_| ServerOptions::new().create(&addr))
                     .map(|l| replace(&mut listener, l));
             }
-        }))
+        })
     }
 }
 
@@ -66,66 +61,3 @@ impl From<NamedPipeClient> for Socket {
         Self::new(socket)
     }
 }
-
-fn get_pipe_name(pipe: &impl AsRawHandle) -> IoResult<std::ffi::OsString> {
-    let mut info: FILE_NAME_INFO = unsafe { zeroed() };
-    let handle = pipe.as_raw_handle();
-
-    let success = unsafe {
-        GetFileInformationByHandleEx(
-            handle as _,
-            FileNameInfo,
-            &mut info as *mut FILE_NAME_INFO as _,
-            size_of::<FILE_NAME_INFO>() as _,
-        )
-    };
-
-    // First call to GetFileInformationByHandleEx should fail with ERROR_MORE_DATA.
-    // This gives us the size we need to allocate to store the data.
-    if success == 0 {
-        let err = IoError::last_os_error();
-        if err.raw_os_error() != Some(ERROR_MORE_DATA as i32) {
-            return Err(err);
-        }
-    }
-
-    // Allocate enough space for a second call to GetFileInformationByHandleEx.
-    let size = size_of::<FILE_NAME_INFO>() + info.FileNameLength as usize;
-    let mut info = vec![0u8; size];
-
-    let success = unsafe {
-        GetFileInformationByHandleEx(handle as _, FileNameInfo, info.as_mut_ptr() as _, size as _)
-    };
-
-    // If the second call fails, bail out.
-    if success == 0 {
-        return Err(IoError::last_os_error());
-    }
-
-    let info = info.as_ptr() as *const FILE_NAME_INFO;
-    let info = unsafe { info.as_ref() }.unwrap();
-
-    let name = unsafe {
-        std::slice::from_raw_parts(info.FileName.as_ptr() as _, (info.FileNameLength / 2) as _)
-    };
-    let name = std::ffi::OsString::from_wide(name);
-    let mut full_name = std::ffi::OsString::from(r"\\.\pipe");
-    full_name.extend([name]);
-
-    Ok(full_name)
-}
-
-#[tokio::test]
-async fn test_get_pipe_name() {
-    let listener = ServerOptions::new()
-        .first_pipe_instance(true)
-        .create(r"\\.\pipe\hello_world")
-        .unwrap();
-
-    let name = get_pipe_name(&listener)
-        .unwrap()
-        .to_string_lossy()
-        .to_string();
-
-    assert_eq!(name, r"\\.\pipe\hello_world");
-}