xapian-core/net/tcpserver.h

   1 /** @file
   2  *  @brief Generic TCP/IP socket based server base class.
   3  */
   4 /* Copyright (C) 2007,2008,2023 Olly Betts
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation; either version 2 of the
   9  * License, or (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
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  19  */
  20
  21 #ifndef XAPIAN_INCLUDED_TCPSERVER_H
  22 #define XAPIAN_INCLUDED_TCPSERVER_H
  23
  24 #ifdef __WIN32__
  25 # include "socket_utils.h"
  26 # define SOCKET_INITIALIZER_MIXIN : private WinsockInitializer
  27 #else
  28 # define SOCKET_INITIALIZER_MIXIN
  29 #endif
  30
  31 #include <xapian/visibility.h>
  32
  33 #include <string>
  34
  35 /** Generic TCP/IP socket based server base class. */
  36 class XAPIAN_VISIBILITY_DEFAULT TcpServer SOCKET_INITIALIZER_MIXIN {
  37     /// Don't allow assignment.
  38     TcpServer& operator=(const TcpServer&) = delete;
  39
  40     /// Don't allow copying.
  41     TcpServer(const TcpServer&) = delete;
  42
  43     /** The socket we're listening on. */
  44     int listener;
  45
  46   protected:
  47     /** Should we produce output when connections are made or lost? */
  48     bool verbose;
  49
  50     /** Accept a connection and return the file descriptor for it. */
  51     XAPIAN_VISIBILITY_INTERNAL
  52     int accept_connection();
  53
  54   public:
  55     /** Construct a TcpServer and start listening for connections.
  56      *
  57      *  @param host     The hostname or address for the interface to listen on
  58      *                  (or "" to listen on all interfaces).
  59      *  @param port     The TCP port number to listen on.
  60      *  @param tcp_nodelay      If true, enable TCP_NODELAY option.
  61      *  @param verbose  Should we produce output when connections are
  62      *                  made or lost?
  63      */
  64     TcpServer(const std::string& host, int port, bool tcp_nodelay,
  65               bool verbose_);
  66
  67     /** Destructor.
  68      *
  69      *  Note: We don't need a virtual destructor despite having a virtual
  70      *  method as we don't ever delete a subclass using a pointer to the
  71      *  base class.
  72      */
  73     ~TcpServer();
  74
  75     /** Accept connections and service requests indefinitely.
  76      *
  77      *  This method runs the TcpServer as a daemon which accepts a connection
  78      *  and forks itself (or creates a new thread under Windows) to serve the
  79      *  request while continuing to listen for more connections.
  80      */
  81     void run();
  82
  83     /** Accept a single connection, service requests on it, then stop.  */
  84     void run_once();
  85
  86     /// Should we produce output when connections are made or lost?
  87     bool get_verbose() const { return verbose; }
  88
  89     /// Handle a single connection on an already connected socket.
  90     virtual void handle_one_connection(int socket) = 0;
  91 };
  92
  93 #endif // XAPIAN_INCLUDED_TCPSERVER_H