File 0218-inets-improve-httpd-do-1-callback-docs-and-spec.patch of Package erlang

From af352b83a233528c7e05064e0d4580dfc2979207 Mon Sep 17 00:00:00 2001
From: Konrad Pietrzak <konrad@erlang.org>
Date: Wed, 28 Jan 2026 15:44:11 +0100
Subject: [PATCH] `inets` improve httpd `do/1` callback docs and spec

---
 lib/inets/src/http_server/httpd.erl | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/lib/inets/src/http_server/httpd.erl b/lib/inets/src/http_server/httpd.erl
index b467329afe..d3486a8e67 100644
--- a/lib/inets/src/http_server/httpd.erl
+++ b/lib/inets/src/http_server/httpd.erl
@@ -865,17 +865,29 @@ that the fun either returns a list `(Body)` that is an HTTP response, or the
 atom `sent` if the HTTP response is sent back to the client. If `close` is
 returned from the fun, something has gone wrong and the server signals this to
 the client by closing the connection.
+
+> #### Note {: .info }
+>
+> It is strongly advised to use NewDataFormat in the return value of `do/1`
+> as it relies on a newer mechanism for parsing and sending headers,
+> provides more accurate status codes, and supports a wider range of Body formats.
+>
+
 """.
 -doc(#{title => <<"ERLANG WEB SERVER API CALLBACK FUNCTIONS">>}).
 -callback do(ModData) -> {proceed, OldData} | {proceed, NewData} | {break, NewData} | done when
       ModData :: [{data,NewData} | {'Body', Body} | {'Head',Head}],
       OldData :: list(),
-      NewData :: [{response, {StatusCode, Body}}],
+      NewData :: [{response, NewDataCompatFormat}] | [{response, NewDataFormat}],
+      NewDataCompatFormat :: {StatusCode, Body},
+      NewDataFormat :: {response, Head, Body} | {already_sent, StatusCode, Size},
       StatusCode :: integer(),
+      Size :: non_neg_integer(),
       Body :: iolist() | nobody | {Fun, FunArg},
-      Head :: [HeaderOption],
+      Head :: [HeaderOption] | {Key, Value},
       HeaderOption :: {Option, Value} | {code, StatusCode},
       Option :: accept_ranges | allow,
+      Key :: atom() | string(),
       Value :: string(),
       FunArg :: [term()],
       Fun :: fun((FunArg) -> sent | close | Body).
-- 
2.51.0