From 5dff2d61cc1c27747ee398e04d8e02843aabb1f8 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Tue, 7 May 2024 04:04:06 +0200 Subject: Adding upstream version 2.4.38. Signed-off-by: Daniel Baumann --- test/test-writev.c | 101 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 101 insertions(+) create mode 100644 test/test-writev.c (limited to 'test/test-writev.c') diff --git a/test/test-writev.c b/test/test-writev.c new file mode 100644 index 0000000..83b6503 --- /dev/null +++ b/test/test-writev.c @@ -0,0 +1,101 @@ +/* Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +/* + test-writev: use this to figure out if your writev() does intelligent + things on the network. Some writev()s when given multiple buffers + will break them up into multiple packets, which is a waste. + + Linux prior to 2.0.31 has this problem. + + Solaris 2.5, 2.5.1 doesn't appear to, 2.6 hasn't been tested. + + IRIX 5.3 doesn't have this problem. + + To use this you want to snoop the wire with tcpdump, and then run + "test-writev a.b.c.d port#" ... against some TCP service on another + box. For example you can run it against port 80 on another server. + You want to look to see how many data packets are sent, you're hoping + only one of size 300 is sent. +*/ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#ifndef INADDR_NONE +#define INADDR_NONE (-1ul) +#endif + +void main( int argc, char **argv ) +{ + struct sockaddr_in server_addr; + int s; + struct iovec vector[3]; + char buf[100]; + int i; + const int just_say_no = 1; + + if( argc != 3 ) { +usage: + fprintf( stderr, "usage: test-writev a.b.c.d port#\n" ); + exit( 1 ); + } + server_addr.sin_family = AF_INET; + server_addr.sin_addr.s_addr = inet_addr( argv[1] ); + if( server_addr.sin_addr.s_addr == INADDR_NONE ) { + fprintf( stderr, "bogus address\n" ); + goto usage; + } + server_addr.sin_port = htons( atoi( argv[2] ) ); + + s = socket( AF_INET, SOCK_STREAM, 0 ); + if( s < 0 ) { + perror("socket"); + exit(1); + } + if( connect( s, (struct sockaddr *)&server_addr, sizeof( server_addr ) ) + != 0 ) { + perror("connect"); + exit(1); + } + + if( setsockopt(s, IPPROTO_TCP, TCP_NODELAY, (char*)&just_say_no, + sizeof(just_say_no)) != 0 ) { + perror( "TCP_NODELAY" ); + exit(1); + } + /* now build up a two part writev and write it out */ + for( i = 0; i < sizeof( buf ); ++i ) { + buf[i] = 'x'; + } + vector[0].iov_base = buf; + vector[0].iov_len = sizeof(buf); + vector[1].iov_base = buf; + vector[1].iov_len = sizeof(buf); + vector[2].iov_base = buf; + vector[2].iov_len = sizeof(buf); + + i = writev( s, &vector[0], 3 ); + fprintf( stdout, "i=%d, errno=%d\n", i, errno ); + exit(0); +} -- cgit v1.2.3