From 3eb44ab7bfc1a5af45e0e05cb1b0bc0899c11af8 Mon Sep 17 00:00:00 2001
From: Rob Ede <robjtede@icloud.com>
Date: Fri, 4 Feb 2022 19:43:54 +0000
Subject: [PATCH] expose ServiceConfig::write_date_header

---
 actix-http/CHANGES.md        |  3 ++-
 actix-http/src/config.rs     | 10 +++++++---
 actix-http/src/h1/encoder.rs |  8 ++++----
 actix-web/CHANGES.md         |  4 ++--
 4 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/actix-http/CHANGES.md b/actix-http/CHANGES.md
index 0585f4f20..2e32c62cd 100644
--- a/actix-http/CHANGES.md
+++ b/actix-http/CHANGES.md
@@ -6,12 +6,13 @@
 
 ### Changed
 - `error::DispatcherError` enum is now marked `#[non_exhaustive]`. [#2624]
+- Expose `ServiceConfig::write_date_header`. [#2625]
 
 ### Fixed
 - Issue where handlers that took payload but then dropped without reading it to EOF it would cause keep-alive connections to become stuck. [#2624]
 
 [#2624]: https://github.com/actix/actix-web/pull/2624
-[#????]: https://github.com/actix/actix-web/pull/????
+[#2625]: https://github.com/actix/actix-web/pull/2625
 
 
 ## 3.0.0-rc.1 - 2022-01-31
diff --git a/actix-http/src/config.rs b/actix-http/src/config.rs
index 8045910be..522c5a023 100644
--- a/actix-http/src/config.rs
+++ b/actix-http/src/config.rs
@@ -104,8 +104,12 @@ impl ServiceConfig {
         self.0.date_service.now()
     }
 
-    pub(crate) fn write_date_header(&self, dst: &mut BytesMut, camel_case: bool) {
-        let mut buf: [u8; 39] = [0; 39];
+    /// Writes date header to `dst` buffer.
+    ///
+    /// Low-level method that utilizes the built-in efficient date service, requiring fewer syscalls
+    /// than normal. Note that a CRLF (`\r\n`) is included in what is written.
+    pub fn write_date_header(&self, dst: &mut BytesMut, camel_case: bool) {
+        let mut buf: [u8; 37] = [0; 37];
 
         buf[..6].copy_from_slice(if camel_case { b"Date: " } else { b"date: " });
 
@@ -113,7 +117,7 @@ impl ServiceConfig {
             .date_service
             .with_date(|date| buf[6..35].copy_from_slice(&date.bytes));
 
-        buf[35..].copy_from_slice(b"\r\n\r\n");
+        buf[35..].copy_from_slice(b"\r\n");
         dst.extend_from_slice(&buf);
     }
 
diff --git a/actix-http/src/h1/encoder.rs b/actix-http/src/h1/encoder.rs
index a24ba5911..ba98f4641 100644
--- a/actix-http/src/h1/encoder.rs
+++ b/actix-http/src/h1/encoder.rs
@@ -210,14 +210,14 @@ pub(crate) trait MessageType: Sized {
             dst.advance_mut(pos);
         }
 
-        // optimized date header, set_date writes \r\n
         if !has_date {
+            // optimized date header, write_date_header writes its own \r\n
             config.write_date_header(dst, camel_case);
-        } else {
-            // msg eof
-            dst.extend_from_slice(b"\r\n");
         }
 
+        // end-of-headers marker
+        dst.extend_from_slice(b"\r\n");
+
         Ok(())
     }
 
diff --git a/actix-web/CHANGES.md b/actix-web/CHANGES.md
index 168888bb3..24d3b2b18 100644
--- a/actix-web/CHANGES.md
+++ b/actix-web/CHANGES.md
@@ -2,9 +2,9 @@
 
 ## Unreleased - 2021-xx-xx
 ### Added
-- Implement `Responder` for `Vec<u8>`. [#????]
+- Implement `Responder` for `Vec<u8>`. [#2625]
 
-[#????]: https://github.com/actix/actix-web/pull/????
+[#2625]: https://github.com/actix/actix-web/pull/2625
 
 ## 4.0.0-rc.2 - 2022-02-02
 ### Added