scheduler/cups-polld.c

   1 /*
   2  * "$Id: cups-polld.c 5871 2006-08-23 20:55:33Z mike $"
   3  *
   4  *   Polling daemon for the Common UNIX Printing System (CUPS).
   5  *
   6  *   Copyright 1997-2006 by Easy Software Products, all rights reserved.
   7  *
   8  *   These coded instructions, statements, and computer programs are the
   9  *   property of Easy Software Products and are protected by Federal
  10  *   copyright law.  Distribution and use rights are outlined in the file
  11  *   "LICENSE.txt" which should have been included with this file.  If this
  12  *   file is missing or damaged please contact Easy Software Products
  13  *   at:
  14  *
  15  *       Attn: CUPS Licensing Information
  16  *       Easy Software Products
  17  *       44141 Airport View Drive, Suite 204
  18  *       Hollywood, Maryland 20636 USA
  19  *
  20  *       Voice: (301) 373-9600
  21  *       EMail: cups-info@cups.org
  22  *         WWW: http://www.cups.org
  23  *
  24  * Contents:
  25  *
  26  *   main()           - Open sockets and poll until we are killed...
  27  *   dequote()        - Remote quotes from a string.
  28  *   poll_server()    - Poll the server for the given set of printers or
  29  *                      classes.
  30  *   sighup_handler() - Handle 'hangup' signals to restart polling.
  31  */
  32
  33 /*
  34  * Include necessary headers...
  35  */
  36
  37 #include <cups/http-private.h>
  38 #include <cups/cups.h>
  39 #include <stdlib.h>
  40 #include <errno.h>
  41 #include <cups/language.h>
  42 #include <cups/string.h>
  43 #include <signal.h>
  44
  45
  46 /*
  47  * Local globals...
  48  */
  49
  50 static int      restart_polling = 1;
  51
  52
  53 /*
  54  * Local functions...
  55  */
  56
  57 static char     *dequote(char *d, const char *s, int dlen);
  58 static int      poll_server(http_t *http, int sock, int port, int interval,
  59                             const char *prefix);
  60 static void     sighup_handler(int sig);
  61
  62
  63 /*
  64  * 'main()' - Open sockets and poll until we are killed...
  65  */
  66
  67 int                                     /* O - Exit status */
  68 main(int  argc,                         /* I - Number of command-line args */
  69      char *argv[])                      /* I - Command-line arguments */
  70 {
  71   http_t        *http;                  /* HTTP connection */
  72   int           interval;               /* Polling interval */
  73   int           sock;                   /* Browser sock */
  74   int           port;                   /* Browser port */
  75   int           val;                    /* Socket option value */
  76   int           seconds,                /* Seconds left from poll */
  77                 remain;                 /* Total remaining time to sleep */
  78   char          prefix[1024];           /* Prefix for log messages */
  79 #if defined(HAVE_SIGACTION) && !defined(HAVE_SIGSET)
  80   struct sigaction action;              /* Actions for POSIX signals */
  81 #endif /* HAVE_SIGACTION && !HAVE_SIGSET */
  82
  83
  84  /*
  85   * Catch hangup signals for when the network changes...
  86   */
  87
  88 #ifdef HAVE_SIGSET /* Use System V signals over POSIX to avoid bugs */
  89   sigset(SIGHUP, sighup_handler);
  90 #elif defined(HAVE_SIGACTION)
  91   memset(&action, 0, sizeof(action));
  92
  93   sigemptyset(&action.sa_mask);
  94   sigaddset(&action.sa_mask, SIGHUP);
  95   action.sa_handler = sighup_handler;
  96   sigaction(SIGHUP, &action, NULL);
  97 #else
  98   signal(SIGHUP, sighup_handler);
  99 #endif /* HAVE_SIGSET */
 100
 101  /*
 102   * Don't buffer log messages...
 103   */
 104
 105   setbuf(stderr, NULL);
 106
 107  /*
 108   * The command-line must contain the following:
 109   *
 110   *    cups-polld server server-port interval port
 111   */
 112
 113   if (argc != 5)
 114   {
 115     fputs("Usage: cups-polld server server-port interval port\n", stderr);
 116     return (1);
 117   }
 118
 119   interval = atoi(argv[3]);
 120   port     = atoi(argv[4]);
 121
 122   if (interval < 2)
 123     interval = 2;
 124
 125   snprintf(prefix, sizeof(prefix), "[cups-polld %s:%d]", argv[1], atoi(argv[2]));
 126
 127  /*
 128   * Open a broadcast socket...
 129   */
 130
 131   if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
 132   {
 133     fprintf(stderr, "ERROR: %s Unable to open broadcast socket: %s\n", prefix,
 134             strerror(errno));
 135     return (1);
 136   }
 137
 138  /*
 139   * Set the "broadcast" flag...
 140   */
 141
 142   val = 1;
 143   if (setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &val, sizeof(val)))
 144   {
 145     fprintf(stderr, "ERROR: %s Unable to put socket in broadcast mode: %s\n",
 146             prefix, strerror(errno));
 147
 148     close(sock);
 149     return (1);
 150   }
 151
 152  /*
 153   * Loop forever, asking for available printers and classes...
 154   */
 155
 156   for (http = NULL;;)
 157   {
 158    /*
 159     * Open a connection to the server...
 160     */
 161
 162     if (restart_polling || !http)
 163     {
 164       restart_polling = 0;
 165       httpClose(http);
 166
 167       if ((http = httpConnectEncrypt(argv[1], atoi(argv[2]),
 168                                      cupsEncryption())) == NULL)
 169       {
 170         fprintf(stderr, "ERROR: %s Unable to connect to %s on port %s: %s\n",
 171                 prefix, argv[1], argv[2],
 172                 h_errno ? hstrerror(h_errno) : strerror(errno));
 173       }
 174     }
 175
 176    /*
 177     * Get the printers and classes...
 178     */
 179
 180     remain = interval;
 181
 182     if (http && (seconds = poll_server(http, sock, port, interval, prefix)) > 0)
 183       remain -= seconds;
 184
 185    /*
 186     * Sleep for any remaining time...
 187     */
 188
 189     if (remain > 0 && !restart_polling)
 190       sleep(remain);
 191   }
 192 }
 193
 194
 195 /*
 196  * 'dequote()' - Remote quotes from a string.
 197  */
 198
 199 static char *                           /* O - Dequoted string */
 200 dequote(char       *d,                  /* I - Destination string */
 201         const char *s,                  /* I - Source string */
 202         int        dlen)                /* I - Destination length */
 203 {
 204   char  *dptr;                          /* Pointer into destination */
 205
 206
 207   if (s)
 208   {
 209     for (dptr = d, dlen --; *s && dlen > 0; s ++)
 210       if (*s != '\"')
 211       {
 212         *dptr++ = *s;
 213         dlen --;
 214       }
 215
 216     *dptr = '\0';
 217   }
 218   else
 219     *d = '\0';
 220
 221   return (d);
 222 }
 223
 224
 225 /*
 226  * 'poll_server()' - Poll the server for the given set of printers or classes.
 227  */
 228
 229 static int                              /* O - Number of seconds or -1 on error */
 230 poll_server(http_t      *http,          /* I - HTTP connection */
 231             int         sock,           /* I - Broadcast sock */
 232             int         port,           /* I - Broadcast port */
 233             int         interval,       /* I - Polling interval */
 234             const char  *prefix)        /* I - Prefix for log messages */
 235 {
 236   int                   seconds;        /* Number of seconds */
 237   int                   count,          /* Current number of printers/classes */
 238                         max_count;      /* Maximum printers/classes per second */
 239   ipp_t                 *request,       /* Request data */
 240                         *response;      /* Response data */
 241   ipp_attribute_t       *attr;          /* Current attribute */
 242   const char            *uri;           /* printer-uri */
 243   char                  info[1024],     /* printer-info */
 244                         job_sheets[1024],/* job-sheets-default */
 245                         location[1024], /* printer-location */
 246                         make_model[1024];
 247                                         /* printer-make-and-model */
 248   cups_ptype_t          type;           /* printer-type */
 249   ipp_pstate_t          state;          /* printer-state */
 250   int                   accepting;      /* printer-is-accepting-jobs */
 251   struct sockaddr_in    addr;           /* Broadcast address */
 252   char                  packet[1540];   /* Data packet */
 253   static const char * const attrs[] =   /* Requested attributes */
 254                         {
 255                           "job-sheets-default",
 256                           "printer-info",
 257                           "printer-is-accepting-jobs",
 258                           "printer-location",
 259                           "printer-make-and-model",
 260                           "printer-name",
 261                           "printer-state",
 262                           "printer-type",
 263                           "printer-uri-supported"
 264                         };
 265
 266
 267  /*
 268   * Broadcast to 127.0.0.1 (localhost)
 269   */
 270
 271   memset(&addr, 0, sizeof(addr));
 272   addr.sin_addr.s_addr = htonl(0x7f000001);
 273   addr.sin_family      = AF_INET;
 274   addr.sin_port        = htons(port);
 275
 276  /*
 277   * Build a CUPS_GET_PRINTERS request and pass along a list of the
 278   * attributes we are interested in along with the types of printers
 279   * (and classes) we want.
 280   */
 281
 282   request = ippNewRequest(CUPS_GET_PRINTERS);
 283
 284   ippAddStrings(request, IPP_TAG_OPERATION, IPP_TAG_KEYWORD,
 285                "requested-attributes", sizeof(attrs) / sizeof(attrs[0]),
 286                NULL, attrs);
 287
 288   ippAddInteger(request, IPP_TAG_OPERATION, IPP_TAG_ENUM,
 289                 "printer-type", 0);
 290   ippAddInteger(request, IPP_TAG_OPERATION, IPP_TAG_ENUM,
 291                 "printer-type-mask",
 292                 CUPS_PRINTER_REMOTE | CUPS_PRINTER_IMPLICIT |
 293                 CUPS_PRINTER_NOT_SHARED);
 294
 295  /*
 296   * Do the request and get back a response...
 297   */
 298
 299   seconds  = time(NULL);
 300   response = cupsDoRequest(http, request, "/");
 301
 302   if (cupsLastError() > IPP_OK_CONFLICT)
 303   {
 304     fprintf(stderr, "ERROR: %s CUPS-Get-Printers failed: %s\n", prefix,
 305             cupsLastErrorString());
 306     ippDelete(response);
 307     return (-1);
 308   }
 309
 310   if (response)
 311   {
 312    /*
 313     * Figure out how many printers/classes we have...
 314     */
 315
 316     for (attr = ippFindAttribute(response, "printer-name", IPP_TAG_NAME),
 317              max_count = 0;
 318          attr != NULL;
 319          attr = ippFindNextAttribute(response, "printer-name", IPP_TAG_NAME),
 320              max_count ++);
 321
 322     fprintf(stderr, "DEBUG: %s Found %d printers.\n", prefix, max_count);
 323
 324     count     = 0;
 325     max_count = max_count / interval + 1;
 326
 327    /*
 328     * Loop through the printers or classes returned in the list...
 329     */
 330
 331     for (attr = response->attrs; attr; attr = attr->next)
 332     {
 333      /*
 334       * Skip leading attributes until we hit a printer...
 335       */
 336
 337       while (attr && attr->group_tag != IPP_TAG_PRINTER)
 338         attr = attr->next;
 339
 340       if (!attr)
 341         break;
 342
 343      /*
 344       * Pull the needed attributes from this printer...
 345       */
 346
 347       uri           = NULL;
 348       info[0]       = '\0';
 349       job_sheets[0] = '\0';
 350       location[0]   = '\0';
 351       make_model[0] = '\0';
 352       type          = CUPS_PRINTER_REMOTE;
 353       accepting     = 1;
 354       state         = IPP_PRINTER_IDLE;
 355
 356       while (attr != NULL && attr->group_tag == IPP_TAG_PRINTER)
 357       {
 358         if (!strcmp(attr->name, "job-sheets-default") &&
 359             (attr->value_tag == IPP_TAG_NAME ||
 360              attr->value_tag == IPP_TAG_KEYWORD))
 361         {
 362           if (attr->num_values == 1)
 363             snprintf(job_sheets, sizeof(job_sheets), " job-sheets=%s",
 364                      attr->values[0].string.text);
 365           else
 366             snprintf(job_sheets, sizeof(job_sheets), " job-sheets=%s,%s",
 367                      attr->values[0].string.text,
 368                      attr->values[1].string.text);
 369         }
 370         else if (!strcmp(attr->name, "printer-uri-supported") &&
 371                  attr->value_tag == IPP_TAG_URI)
 372           uri = attr->values[0].string.text;
 373         else if (!strcmp(attr->name, "printer-info") &&
 374                  attr->value_tag == IPP_TAG_TEXT)
 375           dequote(info, attr->values[0].string.text, sizeof(info));
 376         else if (!strcmp(attr->name, "printer-is-accepting-jobs") &&
 377                  attr->value_tag == IPP_TAG_BOOLEAN)
 378           accepting = attr->values[0].boolean;
 379         else if (!strcmp(attr->name, "printer-location") &&
 380                  attr->value_tag == IPP_TAG_TEXT)
 381           dequote(location, attr->values[0].string.text, sizeof(location));
 382         else if (!strcmp(attr->name, "printer-make-and-model") &&
 383                  attr->value_tag == IPP_TAG_TEXT)
 384           dequote(make_model, attr->values[0].string.text, sizeof(location));
 385         else if (!strcmp(attr->name, "printer-state") &&
 386                  attr->value_tag == IPP_TAG_ENUM)
 387           state = (ipp_pstate_t)attr->values[0].integer;
 388         else if (!strcmp(attr->name, "printer-type") &&
 389                  attr->value_tag == IPP_TAG_ENUM)
 390           type = (cups_ptype_t)attr->values[0].integer;
 391
 392         attr = attr->next;
 393       }
 394
 395      /*
 396       * See if we have everything needed...
 397       */
 398
 399       if (uri == NULL)
 400       {
 401         if (attr == NULL)
 402           break;
 403         else
 404           continue;
 405       }
 406
 407      /*
 408       * Send the printer information...
 409       */
 410
 411       type |= CUPS_PRINTER_REMOTE;
 412
 413       if (!accepting)
 414         type |= CUPS_PRINTER_REJECTING;
 415
 416       snprintf(packet, sizeof(packet),
 417                "%x %x %s \"%s\" \"%s\" \"%s\" lease-duration=%d%s\n",
 418                type, state, uri, location, info, make_model, interval * 2,
 419                job_sheets);
 420
 421       fprintf(stderr, "DEBUG2: %s Sending %s", prefix, packet);
 422
 423       if (sendto(sock, packet, strlen(packet), 0,
 424                  (struct sockaddr *)&addr, sizeof(addr)) <= 0)
 425       {
 426         ippDelete(response);
 427         perror("cups-polld");
 428         return (-1);
 429       }
 430
 431      /*
 432       * Throttle the local broadcasts as needed so that we don't
 433       * overwhelm the local server...
 434       */
 435
 436       count ++;
 437       if (count >= max_count)
 438       {
 439        /*
 440         * Sleep for a second...
 441         */
 442
 443         count = 0;
 444
 445         sleep(1);
 446       }
 447
 448       if (!attr || restart_polling)
 449         break;
 450     }
 451
 452     ippDelete(response);
 453   }
 454
 455  /*
 456   * Return the number of seconds we used...
 457   */
 458
 459   return (time(NULL) - seconds);
 460 }
 461
 462
 463 /*
 464  * 'sighup_handler()' - Handle 'hangup' signals to restart polling.
 465  */
 466
 467 static void
 468 sighup_handler(int sig)                 /* I - Signal number */
 469 {
 470   (void)sig;
 471
 472   restart_polling = 1;
 473
 474 #if !defined(HAVE_SIGSET) && !defined(HAVE_SIGACTION)
 475   signal(SIGHUP, sighup_handler);
 476 #endif /* !HAVE_SIGSET && !HAVE_SIGACTION */
 477 }
 478
 479
 480 /*
 481  * End of "$Id: cups-polld.c 5871 2006-08-23 20:55:33Z mike $".
 482  */