1 // sg_socket.cxx -- Socket I/O routines
3 // Written by Curtis Olson, started November 1999.
5 // Copyright (C) 1999 Curtis L. Olson - http://www.flightgear.org/~curt
7 // This program is free software; you can redistribute it and/or
8 // modify it under the terms of the GNU General Public License as
9 // published by the Free Software Foundation; either version 2 of the
10 // License, or (at your option) any later version.
12 // This program is distributed in the hope that it will be useful, but
13 // WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 // General Public License for more details.
17 // You should have received a copy of the GNU General Public License
18 // along with this program; if not, write to the Free Software
19 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
24 # include <simgear_config.h>
27 #include <simgear/compiler.h>
29 #include <simgear/debug/logstream.hxx>
31 #include "sg_socket_udp.hxx"
34 #include <cstdlib> // for atoi
38 SGSocketUDP::SGSocketUDP( const string& host, const string& port ) :
47 SGSocketUDP::~SGSocketUDP() {
51 // If specified as a server (in direction for now) open the master
52 // listening socket. If specified as a client (out direction), open a
53 // connection to a server.
54 bool SGSocketUDP::open( const SGProtocolDir d ) {
57 if ( ! sock.open( false ) ) { // open a UDP socket
58 SG_LOG( SG_IO, SG_ALERT, "error opening socket" );
62 if ( port_str == "" || port_str == "any" ) {
65 port = atoi( port_str.c_str() );
68 // client_connections.clear();
70 if ( get_dir() == SG_IO_IN ) {
74 if ( sock.bind( hostname.c_str(), port ) == -1 ) {
75 SG_LOG( SG_IO, SG_ALERT, "error binding to port" << port_str );
78 } else if ( get_dir() == SG_IO_OUT ) {
82 if ( sock.connect( hostname.c_str(), port ) == -1 ) {
83 SG_LOG( SG_IO, SG_ALERT,
84 "error connecting to " << hostname << port_str );
88 SG_LOG( SG_IO, SG_ALERT,
89 "Error: bidirection mode not available for UDP sockets." );
99 // read data from socket (server)
100 // read a block of data of specified size
101 int SGSocketUDP::read( char *buf, int length ) {
110 // prevent buffer overflow
111 int maxsize = std::min(length - 1, SG_IO_MAX_MSG_SIZE);
113 if ( (result = sock.recv(buf, maxsize, 0)) >= 0 ) {
115 // printf("msg received = %s\n", buf);
122 // read a line of data, length is max size of input buffer
123 int SGSocketUDP::readline( char *buf, int length ) {
131 // cout << "sock = " << sock << endl;
133 char *buf_ptr = save_buf + save_len;
134 // prevent buffer overflow (size of save_buf is 2 * SG_IO_MAX_MSG_SIZE)
135 int maxsize = save_len < SG_IO_MAX_MSG_SIZE ?
136 SG_IO_MAX_MSG_SIZE : 2 * SG_IO_MAX_MSG_SIZE - save_len;
137 int result = sock.recv(buf_ptr, maxsize, 0);
138 // printf("msg received = %s\n", buf);
141 // look for the end of line in save_buf
143 for ( i = 0; i < save_len && save_buf[i] != '\n'; ++i );
144 if ( save_buf[i] == '\n' ) {
147 // no end of line yet
148 // cout << "no eol found" << endl;
151 // cout << "line length = " << result << endl;
153 // we found an end of line
155 // copy to external buffer
156 // prevent buffer overflow
157 result = std::min(result,length - 1);
158 strncpy( buf, save_buf, result );
160 // cout << "sg_socket line = " << buf << endl;
163 for ( i = result; i < save_len; ++i ) {
164 save_buf[ i - result ] = save_buf[i];
172 // write data to socket (client)
173 int SGSocketUDP::write( const char *buf, const int length ) {
178 if ( sock.send( buf, length, 0 ) < 0 ) {
179 SG_LOG( SG_IO, SG_WARN, "Error writing to socket: " << port );
187 // write null terminated string to socket (server)
188 int SGSocketUDP::writestring( const char *str ) {
193 int length = strlen( str );
194 return write( str, length );
199 bool SGSocketUDP::close() {
210 // configure the socket as non-blocking
211 bool SGSocketUDP::setBlocking( bool value ) {
212 sock.setBlocking( value );