backend/scsi-linux.c

   1 /*
   2  * "$Id: scsi-linux.c 6649 2007-07-11 21:46:42Z mike $"
   3  *
   4  *   Linux SCSI printer support for the Common UNIX Printing System (CUPS).
   5  *
   6  *   Copyright 2007 by Apple Inc.
   7  *   Copyright 2003-2005 by Easy Software Products, all rights reserved.
   8  *
   9  *   Redistribution and use in source and binary forms, with or
  10  *   without modification, are permitted provided that the
  11  *   following conditions are met:
  12  *
  13  *     1. Redistributions of source code must retain the above
  14  *        copyright notice, this list of conditions and the
  15  *        following disclaimer.
  16  *
  17  *     2. Redistributions in binary form must reproduce the
  18  *        above copyright notice, this list of conditions and
  19  *        the following disclaimer in the documentation and/or
  20  *        other materials provided with the distribution.
  21  *
  22  *     3. All advertising materials mentioning features or use
  23  *        of this software must display the following
  24  *        acknowledgement:
  25  *
  26  *          This product includes software developed by Easy
  27  *          Software Products.
  28  *
  29  *     4. The name of Easy Software Products may not be used to
  30  *        endorse or promote products derived from this software
  31  *        without specific prior written permission.
  32  *
  33  *   THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS
  34  *   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
  35  *   BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  36  *   MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  37  *   DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS
  38  *   BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  39  *   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  40  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  41  *   LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  42  *   HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  43  *   CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
  44  *   OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  45  *   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
  46  *   DAMAGE.
  47  *
  48  * Contents:
  49  *
  50  *   list_devices() - List the available SCSI printer devices.
  51  *   print_device() - Print a file to a SCSI device.
  52  */
  53
  54 /*
  55  * Include necessary headers.
  56  */
  57
  58 #include <scsi/sg.h>
  59 #include <cups/i18n.h>
  60
  61
  62 /*
  63  * We currently only support the Linux 2.4 generic SCSI interface.
  64  */
  65
  66 #ifndef SG_DXFER_TO_DEV
  67 /*
  68  * Dummy functions that do nothing on unsupported platforms...
  69  */
  70 void    list_devices(void) {}
  71 int     print_device(const char *resource, int fd, int copies) { return (1); }
  72 #else
  73
  74
  75 /*
  76  * 'list_devices()' - List the available SCSI printer devices.
  77  */
  78
  79 void
  80 list_devices(void)
  81 {
  82   puts("direct scsi \"Unknown\" \"SCSI Printer\"");
  83 }
  84
  85
  86 /*
  87  * 'print_device()' - Print a file to a SCSI device.
  88  */
  89
  90 int                                     /* O - Print status */
  91 print_device(const char *resource,      /* I - SCSI device */
  92              int        fd,             /* I - File to print */
  93              int        copies)         /* I - Number of copies to print */
  94 {
  95   int           scsi_fd;                /* SCSI file descriptor */
  96   char          buffer[8192];           /* Data buffer */
  97   int           bytes;                  /* Number of bytes */
  98   int           try;                    /* Current try */
  99   sg_io_hdr_t   scsi_req;               /* SCSI request */
 100   unsigned char scsi_cmd[6],            /* SCSI command data */
 101                 scsi_sense[32];         /* SCSI sense data */
 102 #  if defined(HAVE_SIGACTION) && !defined(HAVE_SIGSET)
 103   struct sigaction action;              /* Actions for POSIX signals */
 104 #  endif /* HAVE_SIGACTION && !HAVE_SIGSET */
 105
 106
 107  /*
 108   * Make sure we have a valid resource name...
 109   */
 110
 111   if (strncmp(resource, "/dev/sg", 7) != 0)
 112   {
 113     fprintf(stderr, _("ERROR: Bad SCSI device file \"%s\"!\n"), resource);
 114     return (CUPS_BACKEND_STOP);
 115   }
 116
 117  /*
 118   * Open the SCSI device file...
 119   */
 120
 121   fputs("STATE: +connecting-to-device\n", stderr);
 122
 123   do
 124   {
 125     if ((scsi_fd = open(resource, O_RDWR | O_EXCL)) == -1)
 126     {
 127       if (getenv("CLASS") != NULL)
 128       {
 129        /*
 130         * If the CLASS environment variable is set, the job was submitted
 131         * to a class and not to a specific queue.  In this case, we want
 132         * to abort immediately so that the job can be requeued on the next
 133         * available printer in the class.
 134         */
 135
 136         _cupsLangPuts(stderr,
 137                       _("INFO: Unable to contact printer, queuing on next "
 138                         "printer in class...\n"));
 139
 140        /*
 141         * Sleep 5 seconds to keep the job from requeuing too rapidly...
 142         */
 143
 144         sleep(5);
 145
 146         return (CUPS_BACKEND_FAILED);
 147       }
 148
 149       if (errno != EAGAIN && errno != EBUSY)
 150       {
 151         fprintf(stderr, _("ERROR: Unable to open device file \"%s\": %s\n"),
 152                 resource, strerror(errno));
 153         return (CUPS_BACKEND_FAILED);
 154       }
 155       else
 156       {
 157         fputs(_("INFO: Printer busy; will retry in 30 seconds...\n"), stderr);
 158         sleep(30);
 159       }
 160     }
 161   }
 162   while (scsi_fd == -1);
 163
 164   fputs("STATE: -connecting-to-device\n", stderr);
 165
 166  /*
 167   * Now that we are "connected" to the port, ignore SIGTERM so that we
 168   * can finish out any page data the driver sends (e.g. to eject the
 169   * current page...  Only ignore SIGTERM if we are printing data from
 170   * stdin (otherwise you can't cancel raw jobs...)
 171   */
 172
 173   if (fd != 0)
 174   {
 175 #  ifdef HAVE_SIGSET /* Use System V signals over POSIX to avoid bugs */
 176     sigset(SIGTERM, SIG_IGN);
 177 #  elif defined(HAVE_SIGACTION)
 178     memset(&action, 0, sizeof(action));
 179
 180     sigemptyset(&action.sa_mask);
 181     action.sa_handler = SIG_IGN;
 182     sigaction(SIGTERM, &action, NULL);
 183 #  else
 184     signal(SIGTERM, SIG_IGN);
 185 #  endif /* HAVE_SIGSET */
 186   }
 187
 188  /*
 189   * Copy the print file to the device...
 190   */
 191
 192   while (copies > 0)
 193   {
 194     if (fd != 0)
 195       lseek(fd, 0, SEEK_SET);
 196
 197     while ((bytes = read(fd, buffer, sizeof(buffer))) > 0)
 198     {
 199       memset(&scsi_req, 0, sizeof(scsi_req));
 200
 201       scsi_req.interface_id    = 'S';
 202       scsi_req.dxfer_direction = SG_DXFER_TO_DEV;
 203       scsi_req.cmd_len         = 6;
 204       scsi_req.mx_sb_len       = sizeof(scsi_sense);
 205       scsi_req.iovec_count     = 0;
 206       scsi_req.dxfer_len       = bytes;
 207       scsi_req.dxferp          = buffer;
 208       scsi_req.cmdp            = scsi_cmd;
 209       scsi_req.sbp             = scsi_sense;
 210       scsi_req.timeout         = 60 * 1000;
 211
 212       scsi_cmd[0] = 0x0a;       /* Group 0 print command */
 213       scsi_cmd[1] = 0x00;
 214       scsi_cmd[2] = bytes / 65536;
 215       scsi_cmd[3] = bytes / 256;
 216       scsi_cmd[4] = bytes;
 217       scsi_cmd[5] = 0x00;
 218
 219       for (try = 0; try < 10; try ++)
 220         if (ioctl(scsi_fd, SG_IO, &scsi_req) < 0 ||
 221             scsi_req.status != 0)
 222         {
 223           fprintf(stderr,
 224                   _("WARNING: SCSI command timed out (%d); retrying...\n"),
 225                   scsi_req.status);
 226           sleep(try + 1);
 227         }
 228         else
 229           break;
 230
 231       if (try >= 10)
 232       {
 233         fprintf(stderr, _("ERROR: Unable to send print data (%d)\n"),
 234                 scsi_req.status);
 235         close(scsi_fd);
 236         return (CUPS_BACKEND_FAILED);
 237       }
 238     }
 239
 240     copies --;
 241   }
 242
 243  /*
 244   * Close the device and return...
 245   */
 246
 247   close(fd);
 248
 249   return (CUPS_BACKEND_OK);
 250 }
 251 #endif /* !SG_DXFER_TO_DEV */
 252
 253
 254 /*
 255  * End of "$Id: scsi-linux.c 6649 2007-07-11 21:46:42Z mike $".
 256  */