* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
- * Copyright (C) 1998 - 2018, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
}
/*
+ * We're equivalent to Curl_resolver_cancel() for the c-ares resolver. We
+ * never block.
+ */
+void Curl_resolver_kill(struct connectdata *conn)
+{
+ /* We don't need to check the resolver state because we can be called safely
+ at any time and we always do the same thing. */
+ Curl_resolver_cancel(conn);
+}
+
+/*
* destroy_async_data() cleans up async resolver data.
*/
static void destroy_async_data(struct Curl_async *async)
/*
* Curl_resolver_wait_resolv()
*
- * waits for a resolve to finish. This function should be avoided since using
+ * Waits for a resolve to finish. This function should be avoided since using
* this risk getting the multi interface to "hang".
*
* If 'entry' is non-NULL, make it point to the resolved dns entry
*
- * Returns CURLE_COULDNT_RESOLVE_HOST if the host was not resolved, and
- * CURLE_OPERATION_TIMEDOUT if a time-out occurred.
+ * Returns CURLE_COULDNT_RESOLVE_HOST if the host was not resolved,
+ * CURLE_OPERATION_TIMEDOUT if a time-out occurred, or other errors.
*/
CURLcode Curl_resolver_wait_resolv(struct connectdata *conn,
struct Curl_dns_entry **entry)
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
- * Copyright (C) 1998 - 2018, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
}
/*
+ * Until we gain a way to signal the resolver threads to stop early, we must
+ * simply wait for them and ignore their results.
+ */
+void Curl_resolver_kill(struct connectdata *conn)
+{
+ struct thread_data *td = (struct thread_data*) conn->async.os_specific;
+
+ /* If we're still resolving, we must wait for the threads to fully clean up,
+ unfortunately. Otherwise, we can simply cancel to clean up any resolver
+ data. */
+ if(td && td->thread_hnd != curl_thread_t_null)
+ (void)Curl_resolver_wait_resolv(conn, NULL);
+ else
+ Curl_resolver_cancel(conn);
+}
+
+/*
* Curl_resolver_wait_resolv()
*
- * waits for a resolve to finish. This function should be avoided since using
+ * Waits for a resolve to finish. This function should be avoided since using
* this risk getting the multi interface to "hang".
*
* If 'entry' is non-NULL, make it point to the resolved dns entry
*
+ * Returns CURLE_COULDNT_RESOLVE_HOST if the host was not resolved,
+ * CURLE_OPERATION_TIMEDOUT if a time-out occurred, or other errors.
+ *
* This is the version for resolves-in-a-thread.
*/
CURLcode Curl_resolver_wait_resolv(struct connectdata *conn,
CURLcode result = CURLE_OK;
DEBUGASSERT(conn && td);
+ DEBUGASSERT(td->thread_hnd != curl_thread_t_null);
/* wait for the thread to resolve the name */
if(Curl_thread_join(&td->thread_hnd)) {
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
- * Copyright (C) 1998 - 2011, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
*
* It is called from inside other functions to cancel currently performing
* resolver request. Should also free any temporary resources allocated to
- * perform a request.
+ * perform a request. This never waits for resolver threads to complete.
+ *
+ * It is safe to call this when conn is in any state.
*/
void Curl_resolver_cancel(struct connectdata *conn);
+/*
+ * Curl_resolver_kill().
+ *
+ * This acts like Curl_resolver_cancel() except it will block until any threads
+ * associated with the resolver are complete. This never blocks for resolvers
+ * that do not use threads. This is intended to be the "last chance" function
+ * that cleans up an in-progress resolver completely (before its owner is about
+ * to die).
+ *
+ * It is safe to call this when conn is in any state.
+ */
+void Curl_resolver_kill(struct connectdata *conn);
+
/* Curl_resolver_getsock()
*
* This function is called from the multi_getsock() function. 'sock' is a
/*
* Curl_resolver_wait_resolv()
*
- * waits for a resolve to finish. This function should be avoided since using
+ * Waits for a resolve to finish. This function should be avoided since using
* this risk getting the multi interface to "hang".
*
* If 'entry' is non-NULL, make it point to the resolved dns entry
*
- * Returns CURLE_COULDNT_RESOLVE_HOST if the host was not resolved, and
- * CURLE_OPERATION_TIMEDOUT if a time-out occurred.
-
+ * Returns CURLE_COULDNT_RESOLVE_HOST if the host was not resolved,
+ * CURLE_OPERATION_TIMEDOUT if a time-out occurred, or other errors.
*/
CURLcode Curl_resolver_wait_resolv(struct connectdata *conn,
struct Curl_dns_entry **dnsentry);
#ifndef CURLRES_ASYNCH
/* convert these functions if an asynch resolver isn't used */
#define Curl_resolver_cancel(x) Curl_nop_stmt
+#define Curl_resolver_kill(x) Curl_nop_stmt
#define Curl_resolver_is_resolved(x,y) CURLE_COULDNT_RESOLVE_HOST
#define Curl_resolver_wait_resolv(x,y) CURLE_COULDNT_RESOLVE_HOST
#define Curl_resolver_getsock(x,y,z) 0
/* Stop if multi_done() has already been called */
return CURLE_OK;
- if(data->mstate == CURLM_STATE_WAITRESOLVE) {
- /* still waiting for the resolve to complete */
- (void)Curl_resolver_wait_resolv(conn, NULL);
- }
+ /* Stop the resolver and free its own resources (but not dns_entry yet). */
+ Curl_resolver_kill(conn);
Curl_getoff_all_pipelines(data, conn);
}
data->state.done = TRUE; /* called just now! */
- Curl_resolver_cancel(conn);
if(conn->dns_entry) {
Curl_resolv_unlock(data, conn->dns_entry); /* done with this */
# | (__| |_| | _ <| |___
# \___|\___/|_| \_\_____|
#
-# Copyright (C) 1998 - 2018, Daniel Stenberg, <daniel@haxx.se>, et al.
+# Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@haxx.se>, et al.
#
# This software is licensed as described in the file COPYING, which
# you should have received as part of this distribution. The terms
\
test1560 \
\
-test1590 \
+test1590 test1592 \
+\
test1600 test1601 test1602 test1603 test1604 test1605 test1606 test1607 \
test1608 test1609 test1620 \
\
--- /dev/null
+<testcase>
+<info>
+<keywords>
+HTTP
+multi
+resolve
+speedcheck
+</keywords>
+</info>
+
+# Client-side
+<client>
+<server>
+none
+</server>
+<tool>
+lib1592
+</tool>
+ <name>
+HTTP request, remove handle while resolving, don't block
+ </name>
+
+ <command>
+http://a-site-never-accessed.example.org/1592
+</command>
+</client>
+
+# Verify data after the test has been "shot"
+<verify>
+<valgrind>
+disable
+</valgrind>
+<errorcode>
+0
+</errorcode>
+</verify>
+</testcase>
lib1540 \
lib1550 lib1551 lib1552 lib1553 lib1554 lib1555 lib1556 lib1557 \
lib1560 \
+ lib1592 \
lib1900 \
lib2033
lib1560_SOURCES = lib1560.c $(SUPPORTFILES) $(TESTUTIL) $(WARNLESS)
lib1560_LDADD = $(TESTUTIL_LIBS)
+lib1592_SOURCES = lib1592.c $(SUPPORTFILES) $(TESTUTIL) $(WARNLESS)
+lib1592_LDADD = $(TESTUTIL_LIBS)
+lib1592_CPPFLAGS = $(AM_CPPFLAGS) -DLIB1592
+
lib1900_SOURCES = lib1900.c $(SUPPORTFILES) $(TESTUTIL) $(WARNLESS)
lib1900_LDADD = $(TESTUTIL_LIBS)
lib1900_CPPFLAGS = $(AM_CPPFLAGS)
--- /dev/null
+/***************************************************************************
+ * _ _ ____ _
+ * Project ___| | | | _ \| |
+ * / __| | | | |_) | |
+ * | (__| |_| | _ <| |___
+ * \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@haxx.se>, 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.haxx.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.
+ *
+ ***************************************************************************/
+/*
+ * See https://github.com/curl/curl/issues/3371
+ *
+ * This test case checks whether curl_multi_remove_handle() cancels
+ * asynchronous DNS resolvers without blocking where possible. Obviously, it
+ * only tests whichever resolver cURL is actually built with.
+ */
+
+/* We're willing to wait a very generous two seconds for the removal. This is
+ as low as we can go while still easily supporting SIGALRM timing for the
+ non-threaded blocking resolver. It doesn't matter that much because when
+ the test passes, we never wait this long. */
+#define TEST_HANG_TIMEOUT 2 * 1000
+
+#include "test.h"
+#include "testutil.h"
+
+#include <sys/stat.h>
+
+int test(char *URL)
+{
+ int stillRunning;
+ CURLM *multiHandle = NULL;
+ CURL *curl = NULL;
+ CURLMcode res = CURLM_OK;
+ int timeout;
+
+ global_init(CURL_GLOBAL_ALL);
+
+ multi_init(multiHandle);
+
+ easy_init(curl);
+
+ easy_setopt(curl, CURLOPT_VERBOSE, 1L);
+ easy_setopt(curl, CURLOPT_URL, URL);
+
+ /* Set a DNS server that hopefully will not respond when using c-ares. */
+ if(curl_easy_setopt(curl, CURLOPT_DNS_SERVERS, "0.0.0.0") == CURLE_OK)
+ /* Since we could set the DNS server, presume we are working with a
+ resolver that can be cancelled (i.e. c-ares). Thus,
+ curl_multi_remove_handle() should not block even when the resolver
+ request is outstanding. So, set a request timeout _longer_ than the
+ test hang timeout so we will fail if the handle removal call incorrectly
+ blocks. */
+ timeout = TEST_HANG_TIMEOUT * 2;
+ else {
+ /* If we can't set the DNS server, presume that we are configured to use a
+ resolver that can't be cancelled (i.e. the threaded resolver or the
+ non-threaded blocking resolver). So, we just test that the
+ curl_multi_remove_handle() call does finish well within our test
+ timeout.
+
+ But, it is very unlikely that the resolver request will take any time at
+ all because we haven't been able to configure the resolver to use an
+ non-responsive DNS server. At least we exercise the flow.
+ */
+ fprintf(stderr,
+ "CURLOPT_DNS_SERVERS not supported; "
+ "assuming curl_multi_remove_handle() will block\n");
+ timeout = TEST_HANG_TIMEOUT / 2;
+ }
+
+ /* Setting a timeout on the request should ensure that even if we have to
+ wait for the resolver during curl_multi_remove_handle(), it won't take
+ longer than this, because the resolver request inherits its timeout from
+ this. */
+ easy_setopt(curl, CURLOPT_TIMEOUT_MS, timeout);
+
+ multi_add_handle(multiHandle, curl);
+
+ /* This should move the handle from INIT => CONNECT => WAITRESOLVE. */
+ fprintf(stderr, "curl_multi_perform()...\n");
+ multi_perform(multiHandle, &stillRunning);
+ fprintf(stderr, "curl_multi_perform() succeeded\n");
+
+ /* Start measuring how long it takes to remove the handle. */
+ fprintf(stderr, "curl_multi_remove_handle()...\n");
+ start_test_timing();
+ res = curl_multi_remove_handle(multiHandle, curl);
+ if(res) {
+ fprintf(stderr, "curl_multi_remove_handle() failed, "
+ "with code %d\n", (int)res);
+ goto test_cleanup;
+ }
+ fprintf(stderr, "curl_multi_remove_handle() succeeded\n");
+
+ /* Fail the test if it took too long to remove. This happens after the fact,
+ and says "it seems that it would have run forever", which isn't true, but
+ it's close enough, and simple to do. */
+ abort_on_test_timeout();
+
+test_cleanup:
+ curl_easy_cleanup(curl);
+ curl_multi_cleanup(multiHandle);
+ curl_global_cleanup();
+
+ return (int)res;
+}
projects / platform / upstream / curl.git / commitdiff