From 0bc540fbb7e46c7e2988aaec468e6682f3349644 Mon Sep 17 00:00:00 2001
From: Jacob Champion <jacob.champion@enterprisedb.com>
Date: Fri, 30 Jan 2026 16:41:26 -0800
Subject: [PATCH v3 1/6] oauth: Report cleanup errors as warnings on stderr

Using conn->errorMessage for these "shouldn't-happen" cases will only
work if the connection itself fails. Our SSL and password callbacks
print WARNINGs when they find themselves in similar situations, so
follow their lead.
---
 src/interfaces/libpq-oauth/oauth-curl.c | 18 ++++++++----------
 1 file changed, 8 insertions(+), 10 deletions(-)

diff --git a/src/interfaces/libpq-oauth/oauth-curl.c b/src/interfaces/libpq-oauth/oauth-curl.c
index 691e7ec1d9f..19024f6aaa7 100644
--- a/src/interfaces/libpq-oauth/oauth-curl.c
+++ b/src/interfaces/libpq-oauth/oauth-curl.c
@@ -293,10 +293,8 @@ free_async_ctx(PGconn *conn, struct async_ctx *actx)
 	 * no bugs above. But if we do hit them, surfacing those errors somehow
 	 * might be the only way to have a chance to debug them.
 	 *
-	 * TODO: At some point it'd be nice to have a standard way to warn about
-	 * teardown failures. Appending to the connection's error message only
-	 * helps if the bug caused a connection failure; otherwise it'll be
-	 * buried...
+	 * Print them as warnings to stderr, following the example of similar
+	 * situations in fe-secure-openssl.c and fe-connect.c.
 	 */
 
 	if (actx->curlm && actx->curl)
@@ -304,9 +302,9 @@ free_async_ctx(PGconn *conn, struct async_ctx *actx)
 		CURLMcode	err = curl_multi_remove_handle(actx->curlm, actx->curl);
 
 		if (err)
-			libpq_append_conn_error(conn,
-									"libcurl easy handle removal failed: %s",
-									curl_multi_strerror(err));
+			fprintf(stderr,
+					libpq_gettext("WARNING: libcurl easy handle removal failed: %s\n"),
+					curl_multi_strerror(err));
 	}
 
 	if (actx->curl)
@@ -324,9 +322,9 @@ free_async_ctx(PGconn *conn, struct async_ctx *actx)
 		CURLMcode	err = curl_multi_cleanup(actx->curlm);
 
 		if (err)
-			libpq_append_conn_error(conn,
-									"libcurl multi handle cleanup failed: %s",
-									curl_multi_strerror(err));
+			fprintf(stderr,
+					libpq_gettext("WARNING: libcurl multi handle cleanup failed: %s\n"),
+					curl_multi_strerror(err));
 	}
 
 	free_provider(&actx->provider);
-- 
2.34.1

