From 5275aa75403b65db20be5caa8261e9c7fcf3d7c2 Mon Sep 17 00:00:00 2001
From: Christopher Faulet <cfaulet@haproxy.com>
Date: Fri, 17 Jan 2020 16:47:42 +0100
Subject: [PATCH] MINOR: http-rules: Group all processing of early-hint rule in
 its case clause

To know if the 103 response start-line must be added, we test if it is the first
rule of the ruleset or if the previous rule is not an early-hint rule. And at
the end, to know if the 103 response must be terminated, we test if it is the
last rule of the ruleset or if the next rule is not an early-hint rule. This
way, all the code dealing with early-hint rules is grouped in its case clause.
---
 src/http_ana.c | 42 ++++++++++++++++++++++++------------------
 1 file changed, 24 insertions(+), 18 deletions(-)

diff --git a/src/http_ana.c b/src/http_ana.c
index 1002dab4a..9f6c90e0b 100644
--- a/src/http_ana.c
+++ b/src/http_ana.c
@@ -2787,7 +2787,7 @@ static int http_add_early_hint_header(struct stream *s, int early_hints, const s
 		goto fail;
 
 	free_trash_chunk(value);
-	return 1;
+	return 0;
 
   fail:
 	/* If an error occurred during an Early-hint rule, remove the incomplete
@@ -2889,7 +2889,6 @@ static enum rule_result http_req_get_intercept_rule(struct proxy *px, struct lis
 	const char *auth_realm;
 	enum rule_result rule_ret = HTTP_RULE_RES_CONT;
 	int act_opts = 0;
-	int early_hints = 0;
 
 	htx = htxbuf(&s->req.buf);
 
@@ -2926,14 +2925,6 @@ static enum rule_result http_req_get_intercept_rule(struct proxy *px, struct lis
 
 		act_opts |= ACT_OPT_FIRST;
   resume_execution:
-		if (early_hints && rule->action != ACT_HTTP_EARLY_HINT) {
-			early_hints = 0;
-			if (http_reply_103_early_hints(&s->res) == -1) {
-				rule_ret = HTTP_RULE_RES_BADREQ;
-				goto end;
-			}
-		}
-
 		/* Always call the action function if defined */
 		if (rule->action_ptr) {
 			if ((s->req.flags & CF_READ_ERROR) ||
@@ -3037,15 +3028,35 @@ static enum rule_result http_req_get_intercept_rule(struct proxy *px, struct lis
 					http_remove_header(htx, &ctx);
 				break;
 
-			case ACT_HTTP_EARLY_HINT:
+			case ACT_HTTP_EARLY_HINT: {
+				struct act_rule *prev_rule, *next_rule;
+				int early_hints;
+
 				if (!(txn->req.flags & HTTP_MSGF_VER_11))
 					break;
-				early_hints = http_add_early_hint_header(s, early_hints, rule->arg.http.str, &rule->arg.http.fmt);
-				if (early_hints == -1) {
+
+				/* get previous and next rules */
+				prev_rule = LIST_PREV(&rule->list, typeof(rule), list);
+				next_rule = LIST_NEXT(&rule->list, typeof(rule), list);
+
+				/* if no previous rule or previous rule is not early-hint, start a new response. Otherwise,
+				 * continue to add link to a previously started response */
+				early_hints = (&prev_rule->list != rules && prev_rule->action == ACT_HTTP_EARLY_HINT);
+
+				if (http_add_early_hint_header(s, early_hints, rule->arg.http.str, &rule->arg.http.fmt) == -1) {
 					rule_ret = HTTP_RULE_RES_ERROR;
 					goto end;
 				}
+				/* if it is the last rule or the next one is not an early-hint, terminate the current
+				 * response. */
+				if (&next_rule->list == rules || next_rule->action != ACT_HTTP_EARLY_HINT) {
+					if (http_reply_103_early_hints(&s->res) == -1) {
+						rule_ret = HTTP_RULE_RES_ERROR;
+						goto end;
+					}
+				}
 				break;
+			}
 
 			case ACT_ACTION_TRK_SC0 ... ACT_ACTION_TRK_SCMAX:
 				/* Note: only the first valid tracking parameter of each
@@ -3098,11 +3109,6 @@ static enum rule_result http_req_get_intercept_rule(struct proxy *px, struct lis
 	}
 
   end:
-	if (early_hints) {
-		if (http_reply_103_early_hints(&s->res) == -1)
-			rule_ret = HTTP_RULE_RES_ERROR;
-	}
-
 	/* if the ruleset evaluation is finished reset the strict mode */
 	if (rule_ret != HTTP_RULE_RES_YIELD)
 		txn->req.flags &= ~HTTP_MSGF_SOFT_RW;