Line data Source code
1 : // Copyright (c) 2012-2021 Made to Order Software Corp. All Rights Reserved
2 : //
3 : // https://snapwebsites.org/project/eventdispatcher
4 : // contact@m2osw.com
5 : //
6 : // This program is free software; you can redistribute it and/or modify
7 : // it under the terms of the GNU General Public License as published by
8 : // the Free Software Foundation; either version 2 of the License, or
9 : // (at your option) any later version.
10 : //
11 : // This program is distributed in the hope that it will be useful,
12 : // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 : // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 : // GNU General Public License for more details.
15 : //
16 : // You should have received a copy of the GNU General Public License along
17 : // with this program; if not, write to the Free Software Foundation, Inc.,
18 : // 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 :
20 : /** \file
21 : * \brief Implementation of the Snap Communicator class.
22 : *
23 : * This class wraps the C poll() interface in a C++ object with many types
24 : * of objects:
25 : *
26 : * \li Server Connections; for software that want to offer a port to
27 : * which clients can connect to; the server will call accept()
28 : * once a new client connection is ready; this results in a
29 : * Server/Client connection object
30 : * \li Client Connections; for software that want to connect to
31 : * a server; these expect the IP address and port to connect to
32 : * \li Server/Client Connections; for the server when it accepts a new
33 : * connection; in this case the server gets a socket from accept()
34 : * and creates one of these objects to handle the connection
35 : *
36 : * Using the poll() function is the easiest and allows us to listen
37 : * on pretty much any number of sockets (on my server it is limited
38 : * at 16,768 and frankly over 1,000 we probably will start to have
39 : * real slowness issues on small VPN servers.)
40 : */
41 :
42 : // self
43 : //
44 : #include "eventdispatcher/local_stream_server_client_message_connection.h"
45 :
46 : //#include "eventdispatcher/exception.h"
47 :
48 :
49 : // snaplogger lib
50 : //
51 : #include <snaplogger/message.h>
52 :
53 :
54 : // C++ lib
55 : //
56 : //#include <cstring>
57 :
58 :
59 : // C lib
60 : //
61 : //#include <arpa/inet.h>
62 : //#include <sys/socket.h>
63 :
64 :
65 : // last include
66 : //
67 : #include <snapdev/poison.h>
68 :
69 :
70 :
71 : namespace ed
72 : {
73 :
74 :
75 :
76 : /** \brief Initializes a client to read messages from a socket.
77 : *
78 : * This implementation creates a message in/out client.
79 : *
80 : * This is the most useful client on a server in our Snap! environment
81 : * as it directly sends and receives messages.
82 : *
83 : * \param[in] client The client representing the in/out socket.
84 : */
85 1 : local_stream_server_client_message_connection::local_stream_server_client_message_connection(snap::raii_fd_t client)
86 1 : : local_stream_server_client_buffer_connection(std::move(client))
87 : {
88 1 : }
89 :
90 :
91 : /** \brief Process a line (string) just received.
92 : *
93 : * The function parses the line as a message and then calls the
94 : * process_message() function if the line was a valid message.
95 : *
96 : * \param[in] line The line of text that was just read.
97 : */
98 2 : void local_stream_server_client_message_connection::process_line(std::string const & line)
99 : {
100 : // empty lines should not occur, but just in case, just ignore
101 2 : if(line.empty())
102 : {
103 0 : return;
104 : }
105 :
106 4 : message msg;
107 2 : if(msg.from_message(line))
108 : {
109 2 : dispatch_message(msg);
110 : }
111 : else
112 : {
113 : // TODO: what to do here? This could because the version changed
114 : // and the messages are not compatible anymore.
115 : //
116 0 : SNAP_LOG_ERROR
117 0 : << "process_line() was asked to process an invalid message ("
118 : << line
119 : << ")"
120 : << SNAP_LOG_SEND;
121 : }
122 : }
123 :
124 :
125 : /** \brief Send a message.
126 : *
127 : * This function sends a message to the client on the other side
128 : * of this connection.
129 : *
130 : * \exception event_dispatcher_runtime_error
131 : * This function throws this exception if the write() to the pipe
132 : * fails to write the entire message. This should only happen if
133 : * the pipe gets severed.
134 : *
135 : * \param[in] message The message to be processed.
136 : * \param[in] cache Whether to cache the message if there is no connection.
137 : * (Ignore because a client socket has to be there until
138 : * closed and then it can't be reopened by the server.)
139 : *
140 : * \return Always true, although if an error occurs the function throws.
141 : */
142 1 : bool local_stream_server_client_message_connection::send_message(message const & msg, bool cache)
143 : {
144 1 : snap::NOT_USED(cache);
145 :
146 : // transform the message to a string and write to the socket
147 : // the writing is asynchronous so the message is saved in a cache
148 : // and transferred only later when the run() loop is hit again
149 : //
150 2 : std::string buf(msg.to_message());
151 1 : buf += '\n';
152 2 : return write(buf.c_str(), buf.length()) == static_cast<ssize_t>(buf.length());
153 : }
154 :
155 :
156 6 : } // namespace ed
157 : // vim: ts=4 sw=4 et
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