libt2n: (gerd) fix client-connection-logic, finish wrappers, all tests are working...
[libt2n] / src / socket_client.cpp
1 /***************************************************************************
2  *   Copyright (C) 2006 by Gerd v. Egidy                                   *
3  *   gve@intra2net.com                                                     *
4  *                                                                         *
5  *   This library is free software; you can redistribute it and/or modify  *
6  *   it under the terms of the GNU Lesser General Public License version   *
7  *   2.1 as published by the Free Software Foundation.                     *
8  *                                                                         *
9  *   This library is distributed in the hope that it will be useful,       *
10  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
12  *   GNU Lesser General Public License for more details.                   *
13  *                                                                         *
14  *   You should have received a copy of the GNU Lesser General Public      *
15  *   License along with this program; if not, write to the                 *
16  *   Free Software Foundation, Inc.,                                       *
17  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
18  ***************************************************************************/
19
20 #include <stdio.h>
21 #include <errno.h>
22 #include <stdlib.h>
23 #include <unistd.h>
24 #include <sys/types.h>
25 #include <sys/socket.h>
26 #include <sys/un.h>
27 #include <sys/time.h>
28 #include <arpa/inet.h>
29 #include <netinet/in.h>
30 #include <netdb.h>
31 #include <fcntl.h>
32 #include <time.h>
33 #include <pwd.h>
34 #include <grp.h>
35
36 #include <sstream>
37
38 #include "socket_client.hxx"
39 #include "t2n_exception.hxx"
40 #include "log.hxx"
41
42 using namespace std;
43
44 namespace libt2n
45 {
46
47 /// returns a closed connection if connection could not be established, call get_last_error_msg() for details
48 socket_client_connection::socket_client_connection(int _port, const std::string& _server, 
49             long long _connect_timeout_usec, int _max_retries,
50             std::ostream *_logstream, log_level_values _log_level)
51     : client_connection(), socket_handler(0,tcp_s)
52 {
53     max_retries=_max_retries;
54     connect_timeout_usec=_connect_timeout_usec;
55
56     server=_server;
57     port=_port;
58
59     set_logging(_logstream,_log_level);
60
61     try
62     {
63         tcp_connect(max_retries);
64     }
65     catch (t2n_communication_error &e)
66     {
67         lastErrorMsg=e.what();
68         LOGSTREAM(debug,"tcp connect error: " << lastErrorMsg);
69         close();
70     }
71
72     if (!connection::is_closed())
73         do_callbacks(new_connection);
74 }
75
76 /// returns a closed connection if connection could not be established, call get_last_error_msg() for details
77 socket_client_connection::socket_client_connection(const std::string& _path,
78             long long _connect_timeout_usec, int _max_retries,
79             std::ostream *_logstream, log_level_values _log_level)
80     : client_connection(), socket_handler(0,unix_s)
81 {
82     max_retries=_max_retries;
83     connect_timeout_usec=_connect_timeout_usec;
84
85     path=_path;
86
87     set_logging(_logstream,_log_level);
88
89     try
90     {
91         unix_connect(max_retries);
92     }
93     catch (t2n_communication_error &e)
94     {
95         lastErrorMsg=e.what();
96         LOGSTREAM(debug,"unix connect error: " << lastErrorMsg);
97         close();
98     }
99
100     if (!connection::is_closed())
101         do_callbacks(new_connection);
102 }
103
104 void socket_client_connection::tcp_connect(int max_retries)
105 {
106     struct sockaddr_in sock_addr;
107
108     sock_addr.sin_family = AF_INET;
109     sock_addr.sin_port = htons(port);
110
111     // find the target ip
112     if (inet_aton(server.c_str(),&sock_addr.sin_addr)==0)
113     {
114         struct hostent *server_hent;
115         server_hent=gethostbyname(server.c_str());
116         if (server_hent == NULL)
117             throw t2n_connect_error(string("can't find server ")+server);
118
119         memcpy(&sock_addr.sin_addr,server_hent->h_addr_list[0],sizeof(sock_addr.sin_addr));
120     }
121
122     sock = socket(PF_INET, SOCK_STREAM, 0);
123     if (!sock)
124         throw t2n_connect_error(string("socket() error: ")+strerror(errno));
125
126     try
127     {
128         connect_with_timeout((struct sockaddr *) &sock_addr,sizeof(sock_addr));
129     }
130     catch (t2n_connect_error &e)
131     {
132         // recurse if retries left
133         if (max_retries > 0)
134         {
135             LOGSTREAM(debug,"retrying connect after connect error");
136             tcp_connect(max_retries-1);
137         }
138         else
139             throw t2n_connect_error("no more retries left after connect error");
140     }
141 }
142
143 void socket_client_connection::unix_connect(int max_retries)
144 {
145     struct sockaddr_un unix_addr;
146
147     unix_addr.sun_family = AF_UNIX;
148     strcpy (unix_addr.sun_path, path.c_str());
149
150     sock = socket(PF_UNIX, SOCK_STREAM, 0);
151     if (!sock)
152         throw t2n_connect_error(string("socket() error: ")+strerror(errno));
153
154     try
155     {
156         connect_with_timeout((struct sockaddr *) &unix_addr, sizeof(unix_addr));
157     }
158     catch (t2n_connect_error &e)
159     {
160         // recurse if retries left
161         if (max_retries > 0)
162         {
163             LOGSTREAM(debug,"retrying connect after connect error");
164             unix_connect(max_retries-1);
165         }
166         else
167             throw t2n_connect_error("no more retries left after connect error");
168     }
169 }
170
171 void socket_client_connection::connect_with_timeout(struct sockaddr *sock_addr,unsigned int sockaddr_size)
172 {
173     set_socket_options(sock);
174
175     LOGSTREAM(debug,"connect_with_timeout()");
176     int ret=::connect(sock,sock_addr, sockaddr_size);
177
178     if (ret < 0)
179     {
180         if (errno==EINPROGRESS)
181         {
182             LOGSTREAM(debug,"connect_with_timeout(): EINPROGRESS");
183
184             /* set timeout */
185             struct timeval tval;
186             struct timeval *timeout_ptr;
187
188             if (connect_timeout_usec == -1)
189                 timeout_ptr = NULL;
190             else
191             {
192                 timeout_ptr = &tval;
193
194                 // convert timeout from long long usec to int sec + int usec
195                 tval.tv_sec = connect_timeout_usec / 1000000;
196                 tval.tv_usec = connect_timeout_usec % 1000000;
197             }
198
199             fd_set connect_socket_set;
200             FD_ZERO(&connect_socket_set);
201             FD_SET(sock,&connect_socket_set);
202
203             int ret;
204             while ((ret=select(FD_SETSIZE, NULL, &connect_socket_set, NULL, timeout_ptr)) &&
205                     ret < 0 && errno==EINTR);
206
207             if (ret < 0)
208                 throw t2n_connect_error(string("connect() error (select): ")+strerror(errno));
209
210             socklen_t sopt=sizeof(int);
211             int valopt;
212             ret=getsockopt(sock, SOL_SOCKET, SO_ERROR, (void*)(&valopt), &sopt);
213             if (ret < 0 || valopt)
214                 throw t2n_connect_error(string("connect() error (getsockopt): ")+strerror(errno));
215         }
216         else
217             throw t2n_connect_error(string("connect() error: ")+strerror(errno));
218     }
219
220     LOGSTREAM(debug,"connect_with_timeout(): success");
221 }
222
223 void socket_client_connection::close()
224 {
225     if (!client_connection::is_closed())
226     {
227         socket_handler::close();
228         client_connection::close();
229     }
230 }
231
232 /** @brief try to reconnect the current connection with the same connection credentials (host and port or path)
233
234     @note will throw an exeption if reconnecting not possible
235 */
236 void socket_client_connection::reconnect()
237 {
238     LOGSTREAM(debug,"reconnect()");
239
240     // close the current connection if still open
241     close();
242
243     socket_type_value type=get_type();
244
245     if (type == tcp_s)
246         tcp_connect(max_retries);
247     else if (type == unix_s)
248         unix_connect(max_retries);
249
250     // connection is open now, otherwise an execption would have been thrown
251     reopen();
252
253     LOGSTREAM(debug,"reconnect() done, client_connection::is_closed() now " << client_connection::is_closed());
254 }
255
256 }