1// SPDX-License-Identifier: GPL-2.0 2// Test TCP_INQ and TCP_CM_INQ on the server side. 3 4--mss=1000 5 6`./defaults.sh 7` 8 9// Initialize connection 10 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 11 +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 12 +0 bind(3, ..., ...) = 0 13 +0 listen(3, 1) = 0 14 15 +0 < S 0:0(0) win 32792 <mss 1000,sackOK,nop,nop,nop,wscale 10> 16 +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8> 17 +.01 < . 1:1(0) ack 1 win 514 18 19// Accept the connection and enable TCP_INQ. 20 +0 accept(3, ..., ...) = 4 21 +0 setsockopt(4, SOL_TCP, TCP_INQ, [1], 4) = 0 22 23// Now we have 10K of data ready on the socket. 24 +0 < . 1:10001(10000) ack 1 win 514 25 +0 > . 1:1(0) ack 10001 26 27// We read 2K and we should have 8K ready to read. 28 +0 recvmsg(4, {msg_name(...)=..., 29 msg_iov(1)=[{..., 2000}], 30 msg_flags=0, 31 msg_control=[{cmsg_level=SOL_TCP, 32 cmsg_type=TCP_CM_INQ, 33 cmsg_data=8000}]}, 0) = 2000 34// We read 8K and we should have no further data ready to read. 35 +0 recvmsg(4, {msg_name(...)=..., 36 msg_iov(1)=[{..., 8000}], 37 msg_flags=0, 38 msg_control=[{cmsg_level=SOL_TCP, 39 cmsg_type=TCP_CM_INQ, 40 cmsg_data=0}]}, 0) = 8000 41// Client sends more data and closes the connections. 42 +0 < F. 10001:20001(10000) ack 1 win 514 43 +0 > . 1:1(0) ack 20002 44 45// We read 10K and we should have one "fake" byte because the connection is 46// closed. 47 +0 recvmsg(4, {msg_name(...)=..., 48 msg_iov(1)=[{..., 10000}], 49 msg_flags=0, 50 msg_control=[{cmsg_level=SOL_TCP, 51 cmsg_type=TCP_CM_INQ, 52 cmsg_data=1}]}, 0) = 10000 53// Now, receive error. 54 +0 read(3, ..., 2000) = -1 ENOTCONN (Transport endpoint is not connected) 55