From b93d483078ba975973c5aaca931af25b06c6aab8 Mon Sep 17 00:00:00 2001
From: Xudong Huang <huangxu008@hotmail.com>
Date: Sat, 29 Jun 2024 19:21:49 +0800
Subject: [PATCH] :pencil: refine err as cold code

---
 src/http_server.rs | 19 ++++++++++++-------
 src/request.rs     |  6 ++++--
 src/response.rs    |  1 +
 3 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/src/http_server.rs b/src/http_server.rs
index 59bf0ce..08b35b5 100644
--- a/src/http_server.rs
+++ b/src/http_server.rs
@@ -73,6 +73,11 @@ pub trait HttpServiceFactory: Send + Sized + 'static {
     }
 }
 
+#[cold]
+pub(crate) fn err<T>(e: io::Error) -> io::Result<T> {
+    Err(e)
+}
+
 #[cfg(unix)]
 #[inline]
 fn nonblock_read(stream: &mut impl Read, req_buf: &mut BytesMut) -> io::Result<usize> {
@@ -82,10 +87,10 @@ fn nonblock_read(stream: &mut impl Read, req_buf: &mut BytesMut) -> io::Result<u
     let mut read_cnt = 0;
     loop {
         match stream.read(unsafe { read_buf.get_unchecked_mut(read_cnt..) }) {
-            Ok(0) => return Err(io::Error::new(io::ErrorKind::BrokenPipe, "read closed")),
+            Ok(0) => return err(io::Error::new(io::ErrorKind::BrokenPipe, "read closed")),
             Ok(n) => read_cnt += n,
-            Err(err) if err.kind() == io::ErrorKind::WouldBlock => break,
-            Err(err) => return Err(err),
+            Err(e) if e.kind() == io::ErrorKind::WouldBlock => break,
+            Err(e) => return err(e),
         }
     }
 
@@ -105,10 +110,10 @@ fn nonblock_write(stream: &mut impl Write, rsp_buf: &mut BytesMut) -> io::Result
     let mut write_cnt = 0;
     while write_cnt < len {
         match stream.write(unsafe { write_buf.get_unchecked(write_cnt..) }) {
-            Ok(0) => return Err(io::Error::new(io::ErrorKind::BrokenPipe, "write closed")),
+            Ok(0) => return err(io::Error::new(io::ErrorKind::BrokenPipe, "write closed")),
             Ok(n) => write_cnt += n,
-            Err(err) if err.kind() == io::ErrorKind::WouldBlock => break,
-            Err(err) => return Err(err),
+            Err(e) if e.kind() == io::ErrorKind::WouldBlock => break,
+            Err(e) => return err(e),
         }
     }
     rsp_buf.advance(write_cnt);
@@ -184,7 +189,7 @@ fn each_connection_loop<T: HttpService>(stream: &mut TcpStream, mut service: T)
         let read_cnt = stream.read(read_buf)?;
         if read_cnt == 0 {
             //connection was closed
-            return Err(io::Error::new(io::ErrorKind::BrokenPipe, "closed"));
+            return err(io::Error::new(io::ErrorKind::BrokenPipe, "closed"));
         }
         unsafe { req_buf.advance_mut(read_cnt) };
 
diff --git a/src/request.rs b/src/request.rs
index 74569ef..3f1efe9 100644
--- a/src/request.rs
+++ b/src/request.rs
@@ -7,6 +7,8 @@ pub(crate) const MAX_HEADERS: usize = 16;
 use bytes::{Buf, BufMut, BytesMut};
 use may::net::TcpStream;
 
+use crate::http_server::err;
+
 pub struct BodyReader<'buf, 'stream> {
     // remaining bytes for body
     req_buf: &'buf mut BytesMut,
@@ -130,9 +132,9 @@ pub fn decode<'header, 'buf, 'stream>(
     let status = match req.parse_with_uninit_headers(buf, headers) {
         Ok(s) => s,
         Err(e) => {
-            eprintln!("failed to parse http request: {e:?}");
             let msg = format!("failed to parse http request: {e:?}");
-            return Err(io::Error::new(io::ErrorKind::Other, msg));
+            eprintln!("{msg}");
+            return err(io::Error::new(io::ErrorKind::Other, msg));
         }
     };
 
diff --git a/src/response.rs b/src/response.rs
index bc556b5..272fdbe 100644
--- a/src/response.rs
+++ b/src/response.rs
@@ -129,6 +129,7 @@ pub(crate) fn encode(mut rsp: Response, buf: &mut BytesMut) {
     buf.extend_from_slice(rsp.get_body());
 }
 
+#[cold]
 pub(crate) fn encode_error(e: io::Error, buf: &mut BytesMut) {
     error!("error in service: err = {:?}", e);
     let msg_string = e.to_string();