scheduler/listen.c

   1 /*
   2  * "$Id: listen.c,v 1.8 2001/01/22 15:04:00 mike Exp $"
   3  *
   4  *   Server listening routines for the Common UNIX Printing System (CUPS)
   5  *   scheduler.
   6  *
   7  *   Copyright 1997-2001 by Easy Software Products, all rights reserved.
   8  *
   9  *   These coded instructions, statements, and computer programs are the
  10  *   property of Easy Software Products and are protected by Federal
  11  *   copyright law.  Distribution and use rights are outlined in the file
  12  *   "LICENSE.txt" which should have been included with this file.  If this
  13  *   file is missing or damaged please contact Easy Software Products
  14  *   at:
  15  *
  16  *       Attn: CUPS Licensing Information
  17  *       Easy Software Products
  18  *       44141 Airport View Drive, Suite 204
  19  *       Hollywood, Maryland 20636-3111 USA
  20  *
  21  *       Voice: (301) 373-9603
  22  *       EMail: cups-info@cups.org
  23  *         WWW: http://www.cups.org
  24  *
  25  * Contents:
  26  *
  27  *   PauseListening()  - Clear input polling on all listening sockets...
  28  *   ResumeListening() - Set input polling on all listening sockets...
  29  *   StartListening()  - Create all listening sockets...
  30  *   StopListening()   - Close all listening sockets...
  31  */
  32
  33 /*
  34  * Include necessary headers...
  35  */
  36
  37 #include "cupsd.h"
  38
  39
  40 /*
  41  * 'PauseListening()' - Clear input polling on all listening sockets...
  42  */
  43
  44 void
  45 PauseListening(void)
  46 {
  47   int           i;              /* Looping var */
  48   listener_t    *lis;           /* Current listening socket */
  49
  50
  51   if (!FD_ISSET(Listeners[0].fd, &InputSet))
  52     return;
  53
  54   if (NumClients == MaxClients)
  55     LogMessage(L_WARN, "Max clients reached, holding new connections...");
  56
  57   LogMessage(L_DEBUG, "PauseListening: clearing input bits...");
  58
  59   for (i = NumListeners, lis = Listeners; i > 0; i --, lis ++)
  60     FD_CLR(lis->fd, &InputSet);
  61 }
  62
  63
  64 /*
  65  * 'ResumeListening()' - Set input polling on all listening sockets...
  66  */
  67
  68 void
  69 ResumeListening(void)
  70 {
  71   int           i;              /* Looping var */
  72   listener_t    *lis;           /* Current listening socket */
  73
  74
  75   if (FD_ISSET(Listeners[0].fd, &InputSet))
  76     return;
  77
  78   if (NumClients >= (MaxClients - 1))
  79     LogMessage(L_WARN, "Resuming new connection processing...");
  80
  81   LogMessage(L_DEBUG, "ResumeListening: setting input bits...");
  82
  83   for (i = NumListeners, lis = Listeners; i > 0; i --, lis ++)
  84     FD_SET(lis->fd, &InputSet);
  85 }
  86
  87
  88 /*
  89  * 'StartListening()' - Create all listening sockets...
  90  */
  91
  92 void
  93 StartListening(void)
  94 {
  95   int           i,              /* Looping var */
  96                 val;            /* Parameter value */
  97   listener_t    *lis;           /* Current listening socket */
  98   struct hostent *host;         /* Host entry for server address */
  99
 100
 101   LogMessage(L_DEBUG, "StartListening: NumListeners=%d", NumListeners);
 102
 103  /*
 104   * Get the server's IP address...
 105   */
 106
 107   memset(&ServerAddr, 0, sizeof(ServerAddr));
 108
 109   if ((host = gethostbyname(ServerName)) != NULL)
 110   {
 111    /*
 112     * Found the server's address!
 113     */
 114
 115     memcpy((char *)&(ServerAddr.sin_addr), host->h_addr, host->h_length);
 116     ServerAddr.sin_family = host->h_addrtype;
 117   }
 118   else
 119   {
 120    /*
 121     * Didn't find it!  Use an address of 0...
 122     */
 123
 124     LogMessage(L_ERROR, "StartListening: Unable to find IP address for server name \"%s\"!\n",
 125                ServerName);
 126
 127     ServerAddr.sin_family = AF_INET;
 128   }
 129
 130  /*
 131   * Setup socket listeners...
 132   */
 133
 134   for (i = NumListeners, lis = Listeners; i > 0; i --, lis ++)
 135   {
 136     LogMessage(L_DEBUG, "StartListening: address=%08x port=%d",
 137                ntohl(lis->address.sin_addr.s_addr),
 138                ntohs(lis->address.sin_port));
 139
 140     if ((lis->fd = socket(AF_INET, SOCK_STREAM, 0)) == -1)
 141     {
 142       LogMessage(L_ERROR, "StartListening: Unable to open listen socket - %s.",
 143                  strerror(errno));
 144       exit(errno);
 145     }
 146
 147     fcntl(lis->fd, F_SETFD, fcntl(lis->fd, F_GETFD) | FD_CLOEXEC);
 148
 149    /*
 150     * Set things up to reuse the local address for this port.
 151     */
 152
 153     val = 1;
 154 #ifdef __sun
 155     setsockopt(lis->fd, SOL_SOCKET, SO_REUSEADDR, (char *)&val, sizeof(val));
 156 #else
 157     setsockopt(lis->fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
 158 #endif /* __sun */
 159
 160    /*
 161     * Bind to the port we found...
 162     */
 163
 164     if (bind(lis->fd, (struct sockaddr *)&(lis->address), sizeof(lis->address)) < 0)
 165     {
 166       LogMessage(L_ERROR, "StartListening: Unable to bind socket - %s.", strerror(errno));
 167       exit(errno);
 168     }
 169
 170    /*
 171     * Listen for new clients.
 172     */
 173
 174     if (listen(lis->fd, SOMAXCONN) < 0)
 175     {
 176       LogMessage(L_ERROR, "StartListening: Unable to listen for clients - %s.",
 177                  strerror(errno));
 178       exit(errno);
 179     }
 180   }
 181
 182   ResumeListening();
 183 }
 184
 185
 186 /*
 187  * 'StopListening()' - Close all listening sockets...
 188  */
 189
 190 void
 191 StopListening(void)
 192 {
 193   int           i;              /* Looping var */
 194   listener_t    *lis;           /* Current listening socket */
 195
 196
 197   LogMessage(L_DEBUG, "StopListening: closing all listen sockets.");
 198
 199   PauseListening();
 200
 201   for (i = NumListeners, lis = Listeners; i > 0; i --, lis ++)
 202 #if defined(WIN32) || defined(__EMX__)
 203     closesocket(lis->fd);
 204 #else
 205     close(lis->fd);
 206 #endif /* WIN32 || __EMX__ */
 207 }
 208
 209
 210 /*
 211  * End of "$Id: listen.c,v 1.8 2001/01/22 15:04:00 mike Exp $".
 212  */