Merge pull request #16302 from iosabi/lwip_test

lwip_sock: Make sock_tcp_read return more data if available and test it

pkg/lwip/contrib/sock/tcp/lwip_sock_tcp.c

@@ -353,7 +353,12 @@ ssize_t sock_tcp_read(sock_tcp_t *sock, void *data, size_t max_len,
             sock->last_buf = NULL;
             sock->last_offset = 0;
             pbuf_free(buf);
-            break;
+            /* Exit the loop only when there's no more data available in the
+             * connection. This allows to copy more data in a single read if
+             * available. */
+            if (!mbox_avail(&sock->base.conn->recvmbox.mbox)) {
+                break;
+            }
         }
     }
     if (offset > 0) {

tests/lwip/tests/01-run.py

@@ -275,6 +275,55 @@ def test_tcpv6_send(board_group, application, env=None):
         client.expect_exact(u"could not send")
 
 
+def test_tcpv6_large_send(board_group, application, env=None):
+    """Test that the TCP server can receive a large packet in multiple reads"""
+    if any(b.name != "native" for b in board_group.boards):
+        # run test only with native
+        print("SKIP_TEST INFO found non-native board")
+        return
+    env_server = os.environ.copy()
+    if env is not None:
+        env_server.update(env)
+    env_server.update(board_group.boards[1].to_env())
+    with pexpect.spawnu(MAKE, ["-C", application, "term"], env=env_server,
+                        timeout=DEFAULT_TIMEOUT) as server:
+        port = random.randint(0x0000, 0xffff)
+        server_ip = get_ipv6_address(server)
+
+        try:
+            connect_addr = socket.getaddrinfo(
+                "%s%%tapbr0" % server_ip, port)[0][4]
+        except socket.gaierror as e:
+            print("SKIP_TEST INFO", e)
+            return
+
+        server.sendline(u"tcp server start %d" % port)
+        # wait for neighbor discovery to be done
+        time.sleep(5)
+
+        # Send large amount of data to verify multiple reads.
+        with socket.socket(socket.AF_INET6) as sock:
+            sock.connect(connect_addr)
+            server.expect(u"TCP client \\[[0-9a-f:]+\\]:[0-9]+ connected")
+            # Default read size in tcp.c SOCK_INBUF_SIZE (256 bytes), so this
+            # is at least 3 reads.
+            data = bytearray(random.randint(0, 255) for i in range(608))
+            sock.send(data)
+
+            def data_line(i):
+                return u'  '.join(u'%.2X' % data[i + j] for j in range(16))
+            # We expect three consecutive reads of 256 byte buffer to print the
+            # data at positions 0, 256 and 512.
+            server.expect(u"00000000  %s" % data_line(0))
+            server.expect(u"00000000  %s" % data_line(256))
+            server.expect(u"00000000  %s" % data_line(512))
+            # Last line of the message should be on the third read call,
+            # together with the rest of the third read.
+            server.expect(u"00000050  %s" % data_line(len(data) - 16))
+            sock.close()
+            server.expect(u"TCP connection to \\[[0-9a-f:]+\\]:[0-9]+ reset")
+
+
 def test_tcpv6_multiconnect(board_group, application, env=None):
     if any(b.name != "native" for b in board_group.boards):
         # run test only with native
@@ -366,4 +415,5 @@ if __name__ == "__main__":
     TestStrategy().execute([BoardGroup((Board("native", "tap0"),
                             Board("native", "tap1")))],
                            [test_ipv6_send, test_udpv6_send, test_tcpv6_send,
-                            test_tcpv6_multiconnect, test_triple_send])
+                            test_tcpv6_large_send, test_tcpv6_multiconnect,
+                            test_triple_send])