From d1ca974b9f785b928db7758c9985a004bcca7f7e Mon Sep 17 00:00:00 2001
From: Andy Green <andy@warmcat.com>
Date: Sat, 16 Jun 2018 13:24:26 +0800
Subject: [PATCH] http: defer transaction completed if partial pending

This is only helpful for http/1... the real solution is cut up
sending large things.
---
 lib/core/output.c              | 12 ++++++++++++
 lib/roles/h1/ops-h1.c          | 10 ++++++++++
 lib/roles/http/private.h       |  1 +
 lib/roles/http/server/server.c | 15 +++++++++++++++
 4 files changed, 38 insertions(+)

diff --git a/lib/core/output.c b/lib/core/output.c
index e2ff18ef2..11965a06b 100644
--- a/lib/core/output.c
+++ b/lib/core/output.c
@@ -126,6 +126,18 @@ int lws_issue_raw(struct lws *wsi, unsigned char *buf, size_t len)
 				lwsl_info("** %p signalling to close now\n", wsi);
 				return -1; /* retry closing now */
 			}
+
+#if defined(LWS_ROLE_H1) || defined(LWS_ROLE_H2)
+#if !defined(LWS_WITHOUT_SERVER)
+			if (wsi->http.deferred_transaction_completed) {
+				lwsl_notice("%s: partial completed, doing "
+					    "deferred transaction completed\n",
+					    __func__);
+				wsi->http.deferred_transaction_completed = 0;
+				return lws_http_transaction_completed(wsi);
+			}
+#endif
+#endif
 		}
 		/* always callback on writeable */
 		lws_callback_on_writable(wsi);
diff --git a/lib/roles/h1/ops-h1.c b/lib/roles/h1/ops-h1.c
index 8e7294799..9001c864e 100644
--- a/lib/roles/h1/ops-h1.c
+++ b/lib/roles/h1/ops-h1.c
@@ -445,6 +445,16 @@ try_pollout:
 
 	if (lwsi_state(wsi) != LRS_ISSUING_FILE) {
 
+		if (wsi->trunc_len) {
+			//lwsl_notice("%s: completing partial\n", __func__);
+			if (lws_issue_raw(wsi, wsi->trunc_alloc + wsi->trunc_offset,
+					  wsi->trunc_len) < 0) {
+				lwsl_info("%s signalling to close\n", __func__);
+				goto fail;
+			}
+			return LWS_HPI_RET_HANDLED;
+		}
+
 		lws_stats_atomic_bump(wsi->context, pt,
 					LWSSTATS_C_WRITEABLE_CB, 1);
 #if defined(LWS_WITH_STATS)
diff --git a/lib/roles/http/private.h b/lib/roles/http/private.h
index 2aa7a92f7..569991474 100644
--- a/lib/roles/http/private.h
+++ b/lib/roles/http/private.h
@@ -227,6 +227,7 @@ struct _lws_http_mode_related {
 #if defined(LWS_WITH_HTTP_PROXY)
 	unsigned int perform_rewrite:1;
 #endif
+	unsigned int deferred_transaction_completed:1;
 };
 
 
diff --git a/lib/roles/http/server/server.c b/lib/roles/http/server/server.c
index 350af3cd7..9356dbb05 100644
--- a/lib/roles/http/server/server.c
+++ b/lib/roles/http/server/server.c
@@ -1714,6 +1714,21 @@ lws_http_transaction_completed(struct lws *wsi)
 {
 	int n = NO_PENDING_TIMEOUT;
 
+	if (wsi->trunc_len) {
+		/*
+		 * ...so he tried to send something large as the http reply,
+		 * it went as a partial, but he immediately said the
+		 * transaction was completed.
+		 *
+		 * Defer the transaction completed until the last part of the
+		 * partial is sent.
+		 */
+		lwsl_notice("%s: deferring due to partial\n", __func__);
+		wsi->http.deferred_transaction_completed = 1;
+
+		return 0;
+	}
+
 	lwsl_info("%s: wsi %p\n", __func__, wsi);
 
 	lws_access_log(wsi);