backend/scsi-linux.c

   1 /*
   2  * "$Id: scsi-linux.c 6422 2007-03-30 20:49:37Z mike $"
   3  *
   4  *   Linux SCSI printer support for the Common UNIX Printing System (CUPS).
   5  *
   6  *   Copyright 2003-2005 by Easy Software Products, all rights reserved.
   7  *
   8  *   Redistribution and use in source and binary forms, with or
   9  *   without modification, are permitted provided that the
  10  *   following conditions are met:
  11  *
  12  *     1. Redistributions of source code must retain the above
  13  *        copyright notice, this list of conditions and the
  14  *        following disclaimer.
  15  *
  16  *     2. Redistributions in binary form must reproduce the
  17  *        above copyright notice, this list of conditions and
  18  *        the following disclaimer in the documentation and/or
  19  *        other materials provided with the distribution.
  20  *
  21  *     3. All advertising materials mentioning features or use
  22  *        of this software must display the following
  23  *        acknowledgement:
  24  *
  25  *          This product includes software developed by Easy
  26  *          Software Products.
  27  *
  28  *     4. The name of Easy Software Products may not be used to
  29  *        endorse or promote products derived from this software
  30  *        without specific prior written permission.
  31  *
  32  *   THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS
  33  *   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
  34  *   BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  35  *   MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  36  *   DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS
  37  *   BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  38  *   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  39  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  40  *   LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  41  *   HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  42  *   CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
  43  *   OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  44  *   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
  45  *   DAMAGE.
  46  *
  47  * Contents:
  48  *
  49  *   list_devices() - List the available SCSI printer devices.
  50  *   print_device() - Print a file to a SCSI device.
  51  */
  52
  53 /*
  54  * Include necessary headers.
  55  */
  56
  57 #include <scsi/sg.h>
  58 #include <cups/i18n.h>
  59
  60
  61 /*
  62  * We currently only support the Linux 2.4 generic SCSI interface.
  63  */
  64
  65 #ifndef SG_DXFER_TO_DEV
  66 /*
  67  * Dummy functions that do nothing on unsupported platforms...
  68  */
  69 void    list_devices(void) {}
  70 int     print_device(const char *resource, int fd, int copies) { return (1); }
  71 #else
  72
  73
  74 /*
  75  * 'list_devices()' - List the available SCSI printer devices.
  76  */
  77
  78 void
  79 list_devices(void)
  80 {
  81   puts("direct scsi \"Unknown\" \"SCSI Printer\"");
  82 }
  83
  84
  85 /*
  86  * 'print_device()' - Print a file to a SCSI device.
  87  */
  88
  89 int                                     /* O - Print status */
  90 print_device(const char *resource,      /* I - SCSI device */
  91              int        fd,             /* I - File to print */
  92              int        copies)         /* I - Number of copies to print */
  93 {
  94   int           scsi_fd;                /* SCSI file descriptor */
  95   char          buffer[8192];           /* Data buffer */
  96   int           bytes;                  /* Number of bytes */
  97   int           try;                    /* Current try */
  98   sg_io_hdr_t   scsi_req;               /* SCSI request */
  99   unsigned char scsi_cmd[6],            /* SCSI command data */
 100                 scsi_sense[32];         /* SCSI sense data */
 101 #  if defined(HAVE_SIGACTION) && !defined(HAVE_SIGSET)
 102   struct sigaction action;              /* Actions for POSIX signals */
 103 #  endif /* HAVE_SIGACTION && !HAVE_SIGSET */
 104
 105
 106  /*
 107   * Make sure we have a valid resource name...
 108   */
 109
 110   if (strncmp(resource, "/dev/sg", 7) != 0)
 111   {
 112     fprintf(stderr, _("ERROR: Bad SCSI device file \"%s\"!\n"), resource);
 113     return (CUPS_BACKEND_STOP);
 114   }
 115
 116  /*
 117   * Open the SCSI device file...
 118   */
 119
 120   fputs("STATE: +connecting-to-device\n", stderr);
 121
 122   do
 123   {
 124     if ((scsi_fd = open(resource, O_RDWR | O_EXCL)) == -1)
 125     {
 126       if (getenv("CLASS") != NULL)
 127       {
 128        /*
 129         * If the CLASS environment variable is set, the job was submitted
 130         * to a class and not to a specific queue.  In this case, we want
 131         * to abort immediately so that the job can be requeued on the next
 132         * available printer in the class.
 133         */
 134
 135         _cupsLangPuts(stderr,
 136                       _("INFO: Unable to contact printer, queuing on next "
 137                         "printer in class...\n"));
 138
 139        /*
 140         * Sleep 5 seconds to keep the job from requeuing too rapidly...
 141         */
 142
 143         sleep(5);
 144
 145         return (CUPS_BACKEND_FAILED);
 146       }
 147
 148       if (errno != EAGAIN && errno != EBUSY)
 149       {
 150         fprintf(stderr, _("ERROR: Unable to open device file \"%s\": %s\n"),
 151                 resource, strerror(errno));
 152         return (CUPS_BACKEND_FAILED);
 153       }
 154       else
 155       {
 156         fputs(_("INFO: Printer busy; will retry in 30 seconds...\n"), stderr);
 157         sleep(30);
 158       }
 159     }
 160   }
 161   while (scsi_fd == -1);
 162
 163   fputs("STATE: -connecting-to-device\n", stderr);
 164
 165  /*
 166   * Now that we are "connected" to the port, ignore SIGTERM so that we
 167   * can finish out any page data the driver sends (e.g. to eject the
 168   * current page...  Only ignore SIGTERM if we are printing data from
 169   * stdin (otherwise you can't cancel raw jobs...)
 170   */
 171
 172   if (fd != 0)
 173   {
 174 #  ifdef HAVE_SIGSET /* Use System V signals over POSIX to avoid bugs */
 175     sigset(SIGTERM, SIG_IGN);
 176 #  elif defined(HAVE_SIGACTION)
 177     memset(&action, 0, sizeof(action));
 178
 179     sigemptyset(&action.sa_mask);
 180     action.sa_handler = SIG_IGN;
 181     sigaction(SIGTERM, &action, NULL);
 182 #  else
 183     signal(SIGTERM, SIG_IGN);
 184 #  endif /* HAVE_SIGSET */
 185   }
 186
 187  /*
 188   * Copy the print file to the device...
 189   */
 190
 191   while (copies > 0)
 192   {
 193     if (fd != 0)
 194       lseek(fd, 0, SEEK_SET);
 195
 196     while ((bytes = read(fd, buffer, sizeof(buffer))) > 0)
 197     {
 198       memset(&scsi_req, 0, sizeof(scsi_req));
 199
 200       scsi_req.interface_id    = 'S';
 201       scsi_req.dxfer_direction = SG_DXFER_TO_DEV;
 202       scsi_req.cmd_len         = 6;
 203       scsi_req.mx_sb_len       = sizeof(scsi_sense);
 204       scsi_req.iovec_count     = 0;
 205       scsi_req.dxfer_len       = bytes;
 206       scsi_req.dxferp          = buffer;
 207       scsi_req.cmdp            = scsi_cmd;
 208       scsi_req.sbp             = scsi_sense;
 209       scsi_req.timeout         = 60 * 1000;
 210
 211       scsi_cmd[0] = 0x0a;       /* Group 0 print command */
 212       scsi_cmd[1] = 0x00;
 213       scsi_cmd[2] = bytes / 65536;
 214       scsi_cmd[3] = bytes / 256;
 215       scsi_cmd[4] = bytes;
 216       scsi_cmd[5] = 0x00;
 217
 218       for (try = 0; try < 10; try ++)
 219         if (ioctl(scsi_fd, SG_IO, &scsi_req) < 0 ||
 220             scsi_req.status != 0)
 221         {
 222           fprintf(stderr,
 223                   _("WARNING: SCSI command timed out (%d); retrying...\n"),
 224                   scsi_req.status);
 225           sleep(try + 1);
 226         }
 227         else
 228           break;
 229
 230       if (try >= 10)
 231       {
 232         fprintf(stderr, _("ERROR: Unable to send print data (%d)\n"),
 233                 scsi_req.status);
 234         close(scsi_fd);
 235         return (CUPS_BACKEND_FAILED);
 236       }
 237     }
 238
 239     copies --;
 240   }
 241
 242  /*
 243   * Close the device and return...
 244   */
 245
 246   close(fd);
 247
 248   return (CUPS_BACKEND_OK);
 249 }
 250 #endif /* !SG_DXFER_TO_DEV */
 251
 252
 253 /*
 254  * End of "$Id: scsi-linux.c 6422 2007-03-30 20:49:37Z mike $".
 255  */