diff --git a/docs/libcurl/symbols-in-versions b/docs/libcurl/symbols-in-versions
index 4603dd322c..910adc04b4 100644
--- a/docs/libcurl/symbols-in-versions
+++ b/docs/libcurl/symbols-in-versions
@@ -559,6 +559,7 @@ CURLMOPT_MAX_HOST_CONNECTIONS 7.30.0
CURLMOPT_MAX_PIPELINE_LENGTH 7.30.0
CURLMOPT_MAX_TOTAL_CONNECTIONS 7.30.0
CURLMOPT_MAXCONNECTS 7.16.3
+CURLMOPT_NETWORK_CHANGED 8.15.0
CURLMOPT_PIPELINING 7.16.0
CURLMOPT_PIPELINING_SERVER_BL 7.30.0
CURLMOPT_PIPELINING_SITE_BL 7.30.0
diff --git a/include/curl/multi.h b/include/curl/multi.h
index aa1291001f..e39f896940 100644
--- a/include/curl/multi.h
+++ b/include/curl/multi.h
@@ -395,6 +395,9 @@ typedef enum {
/* maximum number of concurrent streams to support on a connection */
CURLOPT(CURLMOPT_MAX_CONCURRENT_STREAMS, CURLOPTTYPE_LONG, 16),
+ /* network has changed, adjust caches/connection reuse */
+ CURLOPT(CURLMOPT_NETWORK_CHANGED, CURLOPTTYPE_LONG, 17),
+
CURLMOPT_LASTENTRY /* the last unused */
} CURLMoption;
diff --git a/lib/conncache.c b/lib/conncache.c
index f77a746874..1393bb565b 100644
--- a/lib/conncache.c
+++ b/lib/conncache.c
@@ -709,7 +709,8 @@ static int cpool_reap_dead_cb(struct Curl_easy *data,
struct connectdata *conn, void *param)
{
struct cpool_reaper_ctx *rctx = param;
- if(Curl_conn_seems_dead(conn, data, &rctx->now)) {
+ if((!CONN_INUSE(conn) && conn->bits.no_reuse) ||
+ Curl_conn_seems_dead(conn, data, &rctx->now)) {
/* stop the iteration here, pass back the connection that was pruned */
Curl_conn_terminate(data, conn, FALSE);
return 1;
@@ -849,6 +850,40 @@ void Curl_cpool_do_locked(struct Curl_easy *data,
cb(conn, data, cbdata);
}
+static int cpool_mark_stale(struct Curl_easy *data,
+ struct connectdata *conn, void *param)
+{
+ (void)data;
+ (void)param;
+ conn->bits.no_reuse = TRUE;
+ return 0;
+}
+
+static int cpool_reap_no_reuse(struct Curl_easy *data,
+ struct connectdata *conn, void *param)
+{
+ (void)data;
+ (void)param;
+ if(!CONN_INUSE(conn) && conn->bits.no_reuse) {
+ Curl_conn_terminate(data, conn, FALSE);
+ return 1;
+ }
+ return 0; /* continue iteration */
+}
+
+void Curl_cpool_nw_changed(struct Curl_easy *data)
+{
+ struct cpool *cpool = cpool_get_instance(data);
+
+ if(cpool) {
+ CPOOL_LOCK(cpool, data);
+ cpool_foreach(data, cpool, NULL, cpool_mark_stale);
+ while(cpool_foreach(data, cpool, NULL, cpool_reap_no_reuse))
+ ;
+ CPOOL_UNLOCK(cpool, data);
+ }
+}
+
#if 0
/* Useful for debugging the connection pool */
void Curl_cpool_print(struct cpool *cpool)
diff --git a/lib/conncache.h b/lib/conncache.h
index ac07111a7d..a5f133344f 100644
--- a/lib/conncache.h
+++ b/lib/conncache.h
@@ -163,4 +163,8 @@ void Curl_cpool_do_locked(struct Curl_easy *data,
struct connectdata *conn,
Curl_cpool_conn_do_cb *cb, void *cbdata);
+/* Close all unused connections, prevent reuse of existing ones. */
+void Curl_cpool_nw_changed(struct Curl_easy *data);
+
+
#endif /* HEADER_CURL_CONNCACHE_H */
diff --git a/lib/easy.c b/lib/easy.c
index e79171a3ae..b526e6cff0 100644
--- a/lib/easy.c
+++ b/lib/easy.c
@@ -1102,6 +1102,7 @@ void curl_easy_reset(CURL *d)
data->progress.hide = TRUE;
data->state.current_speed = -1; /* init to negative == impossible */
data->state.retrycount = 0; /* reset the retry counter */
+ data->state.recent_conn_id = -1; /* clear remembered connection id */
/* zero out authentication data: */
memset(&data->state.authhost, 0, sizeof(struct auth));
diff --git a/lib/hostip.c b/lib/hostip.c
index c1bc3d4633..95c2c62242 100644
--- a/lib/hostip.c
+++ b/lib/hostip.c
@@ -290,6 +290,16 @@ void Curl_dnscache_prune(struct Curl_easy *data)
dnscache_unlock(data, dnscache);
}
+void Curl_dnscache_clear(struct Curl_easy *data)
+{
+ struct Curl_dnscache *dnscache = dnscache_get(data);
+ if(dnscache) {
+ dnscache_lock(data, dnscache);
+ Curl_hash_clean(&dnscache->entries);
+ dnscache_unlock(data, dnscache);
+ }
+}
+
#ifdef USE_ALARM_TIMEOUT
/* Beware this is a global and unique instance. This is used to store the
return address that we can jump back to from inside a signal handler. This
diff --git a/lib/hostip.h b/lib/hostip.h
index cd3d957e1e..56c5e9cad1 100644
--- a/lib/hostip.h
+++ b/lib/hostip.h
@@ -130,6 +130,9 @@ void Curl_dnscache_destroy(struct Curl_dnscache *dns);
/* prune old entries from the DNS cache */
void Curl_dnscache_prune(struct Curl_easy *data);
+/* clear the DNS cache */
+void Curl_dnscache_clear(struct Curl_easy *data);
+
/* IPv4 threadsafe resolve function used for synch and asynch builds */
struct Curl_addrinfo *Curl_ipv4_resolve_r(const char *hostname, int port);
diff --git a/lib/multi.c b/lib/multi.c
index 79d44796ec..f23fc6ec19 100644
--- a/lib/multi.c
+++ b/lib/multi.c
@@ -3235,6 +3235,18 @@ CURLMcode curl_multi_setopt(CURLM *m,
multi->max_concurrent_streams = (unsigned int)streams;
}
break;
+ case CURLMOPT_NETWORK_CHANGED: {
+ long val = va_arg(param, long);
+ if(val >= 2) {
+ /* clear DNS cache */
+ Curl_dnscache_clear(multi->admin);
+ }
+ if(val >= 1) {
+ /* do not reuse existing connections */
+ Curl_cpool_nw_changed(multi->admin);
+ }
+ break;
+ }
default:
res = CURLM_UNKNOWN_OPTION;
break;
diff --git a/lib/url.c b/lib/url.c
index 8a808ef5fd..3a57be4464 100644
--- a/lib/url.c
+++ b/lib/url.c
@@ -843,7 +843,7 @@ static bool url_match_connect_config(struct connectdata *conn,
struct url_conn_match *m)
{
/* connect-only or to-be-closed connections will not be reused */
- if(conn->connect_only || conn->bits.close)
+ if(conn->connect_only || conn->bits.close || conn->bits.no_reuse)
return FALSE;
/* ip_version must match */
diff --git a/lib/urldata.h b/lib/urldata.h
index cae24966eb..8c3a85cdab 100644
--- a/lib/urldata.h
+++ b/lib/urldata.h
@@ -423,6 +423,7 @@ struct ConnectBits {
BIT(parallel_connect); /* set TRUE when a parallel connect attempt has
started (happy eyeballs) */
BIT(aborted); /* connection was aborted, e.g. in unclean state */
+ BIT(no_reuse); /* connection should not be reused */
BIT(shutdown_handler); /* connection shutdown: handler shut down */
BIT(shutdown_filters); /* connection shutdown: filters shut down */
BIT(in_cpool); /* connection is kept in a connection pool */
diff --git a/tests/data/Makefile.am b/tests/data/Makefile.am
index cc3ea533d5..31f61216e6 100644
--- a/tests/data/Makefile.am
+++ b/tests/data/Makefile.am
@@ -273,7 +273,7 @@ test3000 test3001 test3002 test3003 test3004 test3005 test3006 test3007 \
test3008 test3009 test3010 test3011 test3012 test3013 test3014 test3015 \
test3016 test3017 test3018 test3019 test3020 test3021 test3022 test3023 \
test3024 test3025 test3026 test3027 test3028 test3029 test3030 test3031 \
-test3032 \
+test3032 test3033 \
\
test3100 test3101 test3102 test3103 test3104 test3105 \
\
diff --git a/tests/data/test3033 b/tests/data/test3033
new file mode 100644
index 0000000000..8ba008b531
--- /dev/null
+++ b/tests/data/test3033
@@ -0,0 +1,53 @@
+
+
+
+curl_easy_setopt
+connection reuse
+libtest
+
+
+
+#
+# Server-side
+
+
+HTTP/1.1 200 OK
+Content-Length: 6
+
+-foo-
+
+
+[0] no network change
+-foo-
+[1] signal network change
+-foo-
+[2] no network change
+-foo-
+
+
+
+#
+# Client-side
+
+
+http
+
+
+CURLOPT_FRESH_CONNECT=2
+
+
+lib%TESTNUMBER
+
+
+http://%HOSTIP:%HTTPPORT/%TESTNUMBER
+
+
+
+#
+# Verify data after the test has been "shot"
+
+
+0
+
+
+
diff --git a/tests/libtest/Makefile.inc b/tests/libtest/Makefile.inc
index 8878ae85fa..ba402d903b 100644
--- a/tests/libtest/Makefile.inc
+++ b/tests/libtest/Makefile.inc
@@ -93,6 +93,6 @@ TESTS_C = \
lib2402.c lib2404.c lib2405.c \
lib2502.c \
lib2700.c \
- lib3010.c lib3025.c lib3026.c lib3027.c \
+ lib3010.c lib3025.c lib3026.c lib3027.c lib3033.c \
lib3100.c lib3101.c lib3102.c lib3103.c lib3104.c lib3105.c \
lib3207.c lib3208.c
diff --git a/tests/libtest/lib3033.c b/tests/libtest/lib3033.c
new file mode 100644
index 0000000000..6ef25c3de2
--- /dev/null
+++ b/tests/libtest/lib3033.c
@@ -0,0 +1,130 @@
+/***************************************************************************
+ * _ _ ____ _
+ * Project ___| | | | _ \| |
+ * / __| | | | |_) | |
+ * | (__| |_| | _ <| |___
+ * \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) Daniel Stenberg, , 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 "test.h"
+
+#include "testtrace.h"
+#include "testutil.h"
+#include "memdebug.h"
+
+
+static CURLcode t3033_req_test(CURLM *multi, CURL *easy,
+ char *url_3033, int index)
+{
+ CURLMsg *msg = NULL;
+ CURLcode res = CURLE_OK;
+ int still_running = 0;
+
+ if(index == 1) {
+ curl_multi_setopt(multi, CURLMOPT_NETWORK_CHANGED, 1L);
+ curl_mprintf("[1] signal network change\n");
+ }
+ else {
+ curl_mprintf("[%d] no network change\n", index);
+ }
+
+ curl_easy_reset(easy);
+ curl_easy_setopt(easy, CURLOPT_URL, url_3033);
+ easy_setopt(easy, CURLOPT_DEBUGDATA, &libtest_debug_config);
+ easy_setopt(easy, CURLOPT_DEBUGFUNCTION, libtest_debug_cb);
+ easy_setopt(easy, CURLOPT_VERBOSE, 1L);
+
+ curl_multi_add_handle(multi, easy);
+
+ do {
+ CURLMcode mres;
+ int num;
+ curl_multi_perform(multi, &still_running);
+ mres = curl_multi_wait(multi, NULL, 0, TEST_HANG_TIMEOUT, &num);
+ if(mres != CURLM_OK) {
+ curl_mfprintf(stderr, "curl_multi_wait() returned %d\n", mres);
+ res = TEST_ERR_MAJOR_BAD;
+ goto test_cleanup;
+ }
+ } while(still_running);
+
+ do {
+ long num_connects = 0L;
+ msg = curl_multi_info_read(multi, &still_running);
+ if(msg) {
+ if(msg->msg != CURLMSG_DONE)
+ continue;
+
+ res = msg->data.result;
+ if(res != CURLE_OK) {
+ curl_mfprintf(stderr, "curl_multi_info_read() returned %d\n", res);
+ goto test_cleanup;
+ }
+
+ curl_easy_getinfo(easy, CURLINFO_NUM_CONNECTS, &num_connects);
+ if(index == 1 && num_connects == 0) {
+ curl_mprintf("[1] should not reuse connection in pool\n");
+ res = TEST_ERR_MAJOR_BAD;
+ goto test_cleanup;
+ }
+ else if(index == 2 && num_connects) {
+ curl_mprintf("[2] should have reused connection from [1]\n");
+ res = TEST_ERR_MAJOR_BAD;
+ goto test_cleanup;
+ }
+ }
+ } while(msg);
+
+test_cleanup:
+
+ curl_multi_remove_handle(multi, easy);
+
+ return res;
+}
+
+static CURLcode test_lib3033(char *URL)
+{
+ CURL *curl = NULL;
+ CURLM *multi = NULL;
+ CURLcode res = CURLE_OK;
+
+ global_init(CURL_GLOBAL_ALL);
+ multi_init(multi);
+ easy_init(curl);
+
+ libtest_debug_config.nohex = 1;
+ libtest_debug_config.tracetime = 1;
+
+ res = t3033_req_test(multi, curl, URL, 0);
+ if(res != CURLE_OK)
+ goto test_cleanup;
+ res = t3033_req_test(multi, curl, URL, 1);
+ if(res != CURLE_OK)
+ goto test_cleanup;
+ res = t3033_req_test(multi, curl, URL, 2);
+ if(res != CURLE_OK)
+ goto test_cleanup;
+
+test_cleanup:
+
+ curl_easy_cleanup(curl);
+ curl_multi_cleanup(multi);
+ curl_global_cleanup();
+
+ return res; /* return the final return code */
+}