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7e7ee16dd3

Stefan Eissing

2026-08-21

SUCCESS Duration: 408s

Subject

ws: fix write callback error handling

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

lib/ws.c +4 -2 tests/http/test_20_websockets.py +14 -1 tests/libtest/Makefile.inc +1 -0 tests/libtest/cli_ws_write_err.c +136 -0

lib/ws.c+4 -2

@@ -754,7 +754,8 @@ static CURLcode ws_cw_write(struct Curl_easy *data,
	}
	else if(result) {
	failf(data, "[WS] decode payload error %d", (int)result);
-	return result;
+	Curl_bufq_reset(&ctx->buf);
+	goto out;
	}
	}

@@ -812,7 +813,8 @@ static CURLcode ws_cw_flush(struct Curl_easy *data,
	}
	else if(result) {
	failf(data, "[WS] decode payload error %d", (int)result);
-	return result;
+	Curl_bufq_reset(&ctx->buf);
+	goto out;
	}
	}
	}

tests/http/test_20_websockets.py+14 -1

@@ -296,7 +296,10 @@ class TestWebsockets:
	except OSError as e:
	st["err"] = e

-	curl = CurlClient(env=env)
+	run_env = os.environ.copy()
+	if 'CURL_DEBUG' in run_env:
+	del run_env['CURL_DEBUG']
+	curl = CurlClient(env=env, run_env=run_env)
	send_rounds = 2
	threading.Thread(target=srv, daemon=True).start()
	while "p" not in st and "err" not in st:
@@ -344,3 +347,13 @@ class TestWebsockets:
	url = f'ws://localhost:{ws_4frames.port}/large'
	r = client.run(args=[url, payload])
	r.check_exit_code(0)
+
+	# test handling of write callback errors
+	def test_20_14_write_err(self, env: Env, ws_4frames):
+	payload = 127 * "x"
+	client = LocalClient(env=env, name='cli_ws_write_err')
+	if not client.exists():
+	pytest.skip(f'example client not built: {client.name}')
+	url = f'ws://localhost:{ws_4frames.port}/small'
+	r = client.run(args=[url, payload])
+	r.check_exit_code(0)

tests/libtest/Makefile.inc+1 -0

@@ -66,6 +66,7 @@ TESTS_C = \
	cli_ws_data.c \
	cli_ws_pause.c \
	cli_ws_pingpong.c \
+	cli_ws_write_err.c \
	\
	lib500.c lib501.c lib502.c lib503.c lib504.c lib505.c lib506.c lib507.c \
	lib508.c lib509.c lib510.c lib511.c lib512.c lib513.c lib514.c lib515.c \

tests/libtest/cli_ws_write_err.c+136 -0

@@ -0,0 +1,136 @@
+	/***************************************************************************
+	* _ _ ____ _
+	* Project ___\| \| \| \| _ \\| \|
+	* / __\| \| \| \| \|_) \| \|
+	* \| (__\| \|_\| \| _ <\| \|___
+	* \___\|\___/\|_\| \_\_____\|
+	*
+	* Copyright (C) Daniel Stenberg, <[email protected]>, et al.
+	*
+	* This software is licensed as described in the file COPYING, which
+	* you should have received as part of this distribution. The terms
+	* are also available at https://curl.se/docs/copyright.html.
+	*
+	* You may opt to use, copy, modify, merge, publish, distribute and/or sell
+	* copies of the Software, and permit persons to whom the Software is
+	* furnished to do so, under the terms of the COPYING file.
+	*
+	* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+	* KIND, either express or implied.
+	*
+	* SPDX-License-Identifier: curl
+	*
+	***************************************************************************/
+	#include "first.h"
+
+	#include "testtrace.h"
+
+	#ifndef CURL_DISABLE_WEBSOCKETS
+
+	struct test_ws_write_err_ctx {
+	CURL *easy;
+	int callback_count;
+	int errors;
+	int closed;
+	};
+
+	static size_t test_ws_write_err_write_cb(char *ptr, size_t size, size_t nmemb,
+	void *userdata)
+	{
+	struct test_ws_write_err_ctx *ctx = userdata;
+	size_t nbytes = size * nmemb;
+	const struct curl_ws_frame *meta = curl_ws_meta(ctx->easy);
+
+	(void)ptr;
+	ctx->callback_count++;
+	if(!meta) {
+	curl_mfprintf(stderr, "write_cb: ERROR call #%d with meta=NULL\n",
+	ctx->callback_count);
+	++ctx->errors;
+	return CURL_WRITEFUNC_ERROR;
+	}
+	if(ctx->callback_count > 2) {
+	ctx->errors++;
+	curl_mfprintf(stderr, "write_cb: call #%d should not happen\n",
+	ctx->callback_count);
+	return 0;
+	}
+	if(ctx->callback_count > 1) {
+	curl_mfprintf(stderr, "write_cb: call #%d return error\n",
+	ctx->callback_count);
+	return 0;
+	}
+	return nbytes;
+	}
+	#endif /* CURL_DISABLE_WEBSOCKETS */
+
+	static CURLcode test_cli_ws_write_err(const char *URL)
+	{
+	#ifndef CURL_DISABLE_WEBSOCKETS
+	struct test_ws_write_err_ctx ctx;
+	CURLM *multi;
+	int still_running = 0;
+	int msgs_left = 0;
+	int done = 0;
+
+	memset(&ctx, 0, sizeof(ctx));
+	setbuf(stdout, NULL);
+
+	curl_global_init(CURL_GLOBAL_ALL);
+
+	ctx.easy = curl_easy_init();
+	multi = curl_multi_init();
+	if(!ctx.easy \|\| !multi) {
+	curl_mfprintf(stderr, "main: ERROR creating easy/multi\n");
+	ctx.errors = 1;
+	goto out;
+	}
+
+	curl_easy_setopt(ctx.easy, CURLOPT_URL, URL);
+	curl_easy_setopt(ctx.easy, CURLOPT_WRITEFUNCTION,
+	test_ws_write_err_write_cb);
+	curl_easy_setopt(ctx.easy, CURLOPT_WRITEDATA, &ctx);
+	curl_easy_setopt(ctx.easy, CURLOPT_VERBOSE, 1L);
+
+	curl_multi_add_handle(multi, ctx.easy);
+	curl_multi_perform(multi, &still_running);
+
+	while(still_running && !ctx.closed && !ctx.errors) {
+
+	curl_mfprintf(stderr, "main: poll\n");
+	curl_multi_poll(multi, NULL, 0, 100, NULL);
+	curl_mfprintf(stderr, "main: perform\n");
+	curl_multi_perform(multi, &still_running);
+
+	while(!done) {
+	CURLMsg *msg = curl_multi_info_read(multi, &msgs_left);
+	if(!msg)
+	break;
+	if(msg->msg == CURLMSG_DONE) {
+	curl_mfprintf(stderr, "main: done result=%d (%s)\n",
+	(int)msg->data.result,
+	curl_easy_strerror(msg->data.result));
+	done = 1;
+	}
+	}
+	}
+
+	out:
+	if(ctx.easy) {
+	if(multi)
+	curl_multi_remove_handle(multi, ctx.easy);
+	curl_easy_cleanup(ctx.easy);
+	}
+	if(multi)
+	curl_multi_cleanup(multi);
+	curl_global_cleanup();
+
+	return (ctx.errors \|\| (ctx.callback_count != 2)) ?
+	CURLE_WRITE_ERROR : CURLE_OK;
+
+	#else /* !CURL_DISABLE_WEBSOCKETS */
+	(void)URL;
+	curl_mfprintf(stderr, "WebSockets not enabled in libcurl\n");
+	return (CURLcode)1;
+	#endif /* CURL_DISABLE_WEBSOCKETS */
+	}