[PATCH net-next 2/2] vsock/test: Expand linger test to ensure close() does not misbehave

[Michal Luczaj]

Add a check to alert on close() lingering when it should not.

Signed-off-by: Michal Luczaj <m...@rbox.co>
---
 tools/testing/vsock/vsock_test.c | 30 +++++++++++++++++++++++++++---
 1 file changed, 27 insertions(+), 3 deletions(-)

diff --git a/tools/testing/vsock/vsock_test.c b/tools/testing/vsock/vsock_test.c
index 
d0f6d253ac72d08a957cb81a3c38fcc72bec5a53..82d0bc20dfa75041f04eada1b4310be2f7c3a0c1
 100644
--- a/tools/testing/vsock/vsock_test.c
+++ b/tools/testing/vsock/vsock_test.c
@@ -1788,13 +1788,16 @@ static void test_stream_connect_retry_server(const 
struct test_opts *opts)
        close(fd);
 }
 
+#define        LINGER_TIMEOUT  1       /* seconds */
+
 static void test_stream_linger_client(const struct test_opts *opts)
 {
        struct linger optval = {
                .l_onoff = 1,
-               .l_linger = 1
+               .l_linger = LINGER_TIMEOUT
        };
-       int fd;
+       int bytes_unsent, fd;
+       time_t ts;
 
        fd = vsock_stream_connect(opts->peer_cid, opts->peer_port);
        if (fd < 0) {
@@ -1807,7 +1810,28 @@ static void test_stream_linger_client(const struct 
test_opts *opts)
                exit(EXIT_FAILURE);
        }
 
+       /* Byte left unread to expose any incorrect behaviour. */
+       send_byte(fd, 1, 0);
+
+       /* Reuse LINGER_TIMEOUT to wait for bytes_unsent == 0. */
+       timeout_begin(LINGER_TIMEOUT);
+       do {
+               if (ioctl(fd, SIOCOUTQ, &bytes_unsent) < 0) {
+                       perror("ioctl(SIOCOUTQ)");
+                       exit(EXIT_FAILURE);
+               }
+               timeout_check("ioctl(SIOCOUTQ) == 0");
+       } while (bytes_unsent != 0);
+       timeout_end();
+
+       ts = current_nsec();
        close(fd);
+       if ((current_nsec() - ts) / NSEC_PER_SEC > 0) {
+               fprintf(stderr, "Unexpected lingering on close()\n");
+               exit(EXIT_FAILURE);
+       }
+
+       control_writeln("DONE");
 }
 
 static void test_stream_linger_server(const struct test_opts *opts)
@@ -1820,7 +1844,7 @@ static void test_stream_linger_server(const struct 
test_opts *opts)
                exit(EXIT_FAILURE);
        }
 
-       vsock_wait_remote_close(fd);
+       control_expectln("DONE");
        close(fd);
 }
 

-- 
2.49.0