[thirdparty/cups.git] / backend / runloop.c

/*
 * "$Id: runloop.c 9565 2011-02-23 00:08:08Z mike $"
 *
 *   Common run loop APIs for CUPS backends.
 *
 *   Copyright 2007-2011 by Apple Inc.
 *   Copyright 2006-2007 by Easy Software Products, all rights reserved.
 *
 *   These coded instructions, statements, and computer programs are the
 *   property of Apple Inc. and are protected by Federal copyright
 *   law.  Distribution and use rights are outlined in the file "LICENSE.txt"
 *   "LICENSE" which should have been included with this file.  If this
 *   file is missing or damaged, see the license at "http://www.cups.org/".
 *
 *   This file is subject to the Apple OS-Developed Software exception.
 *
 * Contents:
 *
 *   backendDrainOutput() - Drain pending print data to the device.
 *   backendRunLoop()     - Read and write print and back-channel data.
 *   backendWaitLoop()    - Wait for input from stdin while handling
 *                          side-channel queries.
 */

/*
 * Include necessary headers.
 */

#include "backend-private.h"
#include <limits.h>
#ifdef __hpux
#  include <sys/time.h>
#else
#  include <sys/select.h>
#endif /* __hpux */


/*
 * 'backendDrainOutput()' - Drain pending print data to the device.
 */

int					/* O - 0 on success, -1 on error */
backendDrainOutput(int print_fd,	/* I - Print file descriptor */
                   int device_fd)	/* I - Device file descriptor */
{
  int		nfds;			/* Maximum file descriptor value + 1 */
  fd_set	input;			/* Input set for reading */
  ssize_t	print_bytes,		/* Print bytes read */
		bytes;			/* Bytes written */
  char		print_buffer[8192],	/* Print data buffer */
		*print_ptr;		/* Pointer into print data buffer */
  struct timeval timeout;		/* Timeout for read... */


  fprintf(stderr, "DEBUG: backendDrainOutput(print_fd=%d, device_fd=%d)\n",
          print_fd, device_fd);

 /*
  * Figure out the maximum file descriptor value to use with select()...
  */

  nfds = (print_fd > device_fd ? print_fd : device_fd) + 1;

 /*
  * Now loop until we are out of data from print_fd...
  */

  for (;;)
  {
   /*
    * Use select() to determine whether we have data to copy around...
    */

    FD_ZERO(&input);
    FD_SET(print_fd, &input);

    timeout.tv_sec  = 0;
    timeout.tv_usec = 0;

    if (select(nfds, &input, NULL, NULL, &timeout) < 0)
      return (-1);

    if (!FD_ISSET(print_fd, &input))
      return (0);

    if ((print_bytes = read(print_fd, print_buffer,
			    sizeof(print_buffer))) < 0)
    {
     /*
      * Read error - bail if we don't see EAGAIN or EINTR...
      */

      if (errno != EAGAIN || errno != EINTR)
      {
        _cupsLangPrintError("ERROR", _("Unable to read print data"));
	return (-1);
      }

      print_bytes = 0;
    }
    else if (print_bytes == 0)
    {
     /*
      * End of file, return...
      */

      return (0);
    }

    fprintf(stderr, "DEBUG: Read %d bytes of print data...\n",
	    (int)print_bytes);

    for (print_ptr = print_buffer; print_bytes > 0;)
    {
      if ((bytes = write(device_fd, print_ptr, print_bytes)) < 0)
      {
       /*
        * Write error - bail if we don't see an error we can retry...
	*/

        if (errno != ENOSPC && errno != ENXIO && errno != EAGAIN &&
	    errno != EINTR && errno != ENOTTY)
	{
	  _cupsLangPrintError("ERROR", _("Unable to write print data"));
	  return (-1);
	}
      }
      else
      {
        fprintf(stderr, "DEBUG: Wrote %d bytes of print data...\n", (int)bytes);

        print_bytes -= bytes;
	print_ptr   += bytes;
      }
    }
  }
}


/*
 * 'backendRunLoop()' - Read and write print and back-channel data.
 */

ssize_t					/* O - Total bytes on success, -1 on error */
backendRunLoop(
    int          print_fd,		/* I - Print file descriptor */
    int          device_fd,		/* I - Device file descriptor */
    int          snmp_fd,		/* I - SNMP socket or -1 if none */
    http_addr_t  *addr,			/* I - Address of device */
    int          use_bc,		/* I - Use back-channel? */
    int          update_state,		/* I - Update printer-state-reasons? */
    _cups_sccb_t side_cb)		/* I - Side-channel callback */
{
  int		nfds;			/* Maximum file descriptor value + 1 */
  fd_set	input,			/* Input set for reading */
		output;			/* Output set for writing */
  ssize_t	print_bytes,		/* Print bytes read */
		bc_bytes,		/* Backchannel bytes read */
		total_bytes,		/* Total bytes written */
		bytes;			/* Bytes written */
  int		paperout;		/* "Paper out" status */
  int		offline;		/* "Off-line" status */
  char		print_buffer[8192],	/* Print data buffer */
		*print_ptr,		/* Pointer into print data buffer */
		bc_buffer[1024];	/* Back-channel data buffer */
  struct timeval timeout;		/* Timeout for select() */
  time_t	curtime,		/* Current time */
		snmp_update = 0;
#if defined(HAVE_SIGACTION) && !defined(HAVE_SIGSET)
  struct sigaction action;		/* Actions for POSIX signals */
#endif /* HAVE_SIGACTION && !HAVE_SIGSET */


  fprintf(stderr,
          "DEBUG: backendRunLoop(print_fd=%d, device_fd=%d, snmp_fd=%d, "
	  "addr=%p, use_bc=%d, side_cb=%p)\n",
          print_fd, device_fd, snmp_fd, addr, use_bc, side_cb);

 /*
  * If we are printing data from a print driver on stdin, ignore SIGTERM
  * so that the driver can finish out any page data, e.g. to eject the
  * current page.  We only do this for stdin printing as otherwise there
  * is no way to cancel a raw print job...
  */

  if (!print_fd)
  {
#ifdef HAVE_SIGSET /* Use System V signals over POSIX to avoid bugs */
    sigset(SIGTERM, SIG_IGN);
#elif defined(HAVE_SIGACTION)
    memset(&action, 0, sizeof(action));

    sigemptyset(&action.sa_mask);
    action.sa_handler = SIG_IGN;
    sigaction(SIGTERM, &action, NULL);
#else
    signal(SIGTERM, SIG_IGN);
#endif /* HAVE_SIGSET */
  }
  else if (print_fd < 0)
  {
   /*
    * Copy print data from stdin, but don't mess with the signal handlers...
    */

    print_fd = 0;
  }

 /*
  * Figure out the maximum file descriptor value to use with select()...
  */

  nfds = (print_fd > device_fd ? print_fd : device_fd) + 1;

 /*
  * Now loop until we are out of data from print_fd...
  */

  for (print_bytes = 0, print_ptr = print_buffer, offline = -1,
           paperout = -1, total_bytes = 0;;)
  {
   /*
    * Use select() to determine whether we have data to copy around...
    */

    FD_ZERO(&input);
    if (!print_bytes)
      FD_SET(print_fd, &input);
    if (use_bc)
      FD_SET(device_fd, &input);
    if (!print_bytes && side_cb)
      FD_SET(CUPS_SC_FD, &input);

    FD_ZERO(&output);
    if (print_bytes || (!use_bc && !side_cb))
      FD_SET(device_fd, &output);

    if (use_bc || side_cb)
    {
      timeout.tv_sec  = 5;
      timeout.tv_usec = 0;

      if (select(nfds, &input, &output, NULL, &timeout) < 0)
      {
       /*
	* Pause printing to clear any pending errors...
	*/

	if (errno == ENXIO && offline != 1 && update_state)
	{
	  fputs("STATE: +offline-report\n", stderr);
	  _cupsLangPrintFilter(stderr, "INFO",
	                       _("Printer is not currently connected."));
	  offline = 1;
	}
	else if (errno == EINTR && total_bytes == 0)
	{
	  fputs("DEBUG: Received an interrupt before any bytes were "
	        "written, aborting.\n", stderr);
          return (0);
	}

	sleep(1);
	continue;
      }
    }

   /*
    * Check if we have a side-channel request ready...
    */

    if (side_cb && FD_ISSET(CUPS_SC_FD, &input))
    {
     /*
      * Do the side-channel request, then start back over in the select
      * loop since it may have read from print_fd...
      */

      if ((*side_cb)(print_fd, device_fd, snmp_fd, addr, use_bc))
        side_cb = NULL;
      continue;
    }

   /*
    * Check if we have back-channel data ready...
    */

    if (FD_ISSET(device_fd, &input))
    {
      if ((bc_bytes = read(device_fd, bc_buffer, sizeof(bc_buffer))) > 0)
      {
	fprintf(stderr,
	        "DEBUG: Received " CUPS_LLFMT " bytes of back-channel data\n",
	        CUPS_LLCAST bc_bytes);
        cupsBackChannelWrite(bc_buffer, bc_bytes, 1.0);
      }
      else if (bc_bytes < 0 && errno != EAGAIN && errno != EINTR)
      {
        fprintf(stderr, "DEBUG: Error reading back-channel data: %s\n",
	        strerror(errno));
	use_bc = 0;
      }
      else if (bc_bytes == 0)
        use_bc = 0;
    }

   /*
    * Check if we have print data ready...
    */

    if (FD_ISSET(print_fd, &input))
    {
      if ((print_bytes = read(print_fd, print_buffer,
                              sizeof(print_buffer))) < 0)
      {
       /*
        * Read error - bail if we don't see EAGAIN or EINTR...
	*/

	if (errno != EAGAIN || errno != EINTR)
	{
	  _cupsLangPrintError("ERROR", _("Unable to read print data"));
	  return (-1);
	}

        print_bytes = 0;
      }
      else if (print_bytes == 0)
      {
       /*
        * End of file, break out of the loop...
	*/

        break;
      }

      print_ptr = print_buffer;

      fprintf(stderr, "DEBUG: Read %d bytes of print data...\n",
              (int)print_bytes);
    }

   /*
    * Check if the device is ready to receive data and we have data to
    * send...
    */

    if (print_bytes && FD_ISSET(device_fd, &output))
    {
      if ((bytes = write(device_fd, print_ptr, print_bytes)) < 0)
      {
       /*
        * Write error - bail if we don't see an error we can retry...
	*/

        if (errno == ENOSPC)
	{
	  if (paperout != 1 && update_state)
	  {
	    fputs("STATE: +media-empty-warning\n", stderr);
	    fputs("DEBUG: Out of paper\n", stderr);
	    paperout = 1;
	  }
        }
	else if (errno == ENXIO)
	{
	  if (offline != 1 && update_state)
	  {
	    fputs("STATE: +offline-report\n", stderr);
	    _cupsLangPrintFilter(stderr, "INFO",
	                         _("Printer is not currently connected."));
	    offline = 1;
	  }
	}
	else if (errno != EAGAIN && errno != EINTR && errno != ENOTTY)
	{
	  _cupsLangPrintError("ERROR", _("Unable to write print data"));
	  return (-1);
	}
      }
      else
      {
        if (paperout && update_state)
	{
	  fputs("STATE: -media-empty-warning\n", stderr);
	  paperout = 0;
	}

	if (offline && update_state)
	{
	  fputs("STATE: -offline-report\n", stderr);
	  _cupsLangPrintFilter(stderr, "INFO", _("Printer is now connected."));
	  offline = 0;
	}

        fprintf(stderr, "DEBUG: Wrote %d bytes of print data...\n", (int)bytes);

        print_bytes -= bytes;
	print_ptr   += bytes;
	total_bytes += bytes;
      }
    }

   /*
    * Do SNMP updates periodically...
    */

    if (snmp_fd >= 0 && time(&curtime) >= snmp_update)
    {
      if (backendSNMPSupplies(snmp_fd, addr, NULL, NULL))
        snmp_update = INT_MAX;
      else
        snmp_update = curtime + 5;
    }
  }

 /*
  * Return with success...
  */

  return (total_bytes);
}


/*
 * 'backendWaitLoop()' - Wait for input from stdin while handling side-channel
 *                       queries.
 */

int					/* O - 1 if data is ready, 0 if not */
backendWaitLoop(
    int          snmp_fd,		/* I - SNMP socket or -1 if none */
    http_addr_t  *addr,			/* I - Address of device */
    int          use_bc,		/* I - Use back-channel? */
    _cups_sccb_t side_cb)		/* I - Side-channel callback */
{
  fd_set	input;			/* Input set for reading */
  time_t	curtime,		/* Current time */
		snmp_update = 0;	/* Last SNMP status update */


  fprintf(stderr, "DEBUG: backendWaitLoop(snmp_fd=%d, addr=%p, side_cb=%p)\n",
	  snmp_fd, addr, side_cb);

 /*
  * Now loop until we receive data from stdin...
  */

  for (;;)
  {
   /*
    * Use select() to determine whether we have data to copy around...
    */

    FD_ZERO(&input);
    FD_SET(0, &input);
    if (side_cb)
      FD_SET(CUPS_SC_FD, &input);

    if (select(CUPS_SC_FD + 1, &input, NULL, NULL, NULL) < 0)
    {
     /*
      * Pause printing to clear any pending errors...
      */

      if (errno == EINTR)
      {
	fputs("DEBUG: Received an interrupt before any bytes were "
	      "written, aborting.\n", stderr);
	return (0);
      }

      sleep(1);
      continue;
    }

   /*
    * Check for input on stdin...
    */

    if (FD_ISSET(0, &input))
      break;

   /*
    * Check if we have a side-channel request ready...
    */

    if (side_cb && FD_ISSET(CUPS_SC_FD, &input))
    {
     /*
      * Do the side-channel request, then start back over in the select
      * loop since it may have read from print_fd...
      */

      if ((*side_cb)(0, -1, snmp_fd, addr, use_bc))
        side_cb = NULL;
      continue;
    }

   /*
    * Do SNMP updates periodically...
    */

    if (snmp_fd >= 0 && time(&curtime) >= snmp_update)
    {
      if (backendSNMPSupplies(snmp_fd, addr, NULL, NULL))
        snmp_update = INT_MAX;
      else
        snmp_update = curtime + 5;
    }
  }

 /*
  * Return with success...
  */

  return (1);
}


/*
 * End of "$Id: runloop.c 9565 2011-02-23 00:08:08Z mike $".
 */
Commit	Line	Data
ed486911	1	/*
c8fef167	2	* "$Id: runloop.c 9565 2011-02-23 00:08:08Z mike $"
ed486911	3	*
c8fef167	4	* Common run loop APIs for CUPS backends.
ed486911	5	*
c8fef167	6	* Copyright 2007-2011 by Apple Inc.
f7deaa1a	7	* Copyright 2006-2007 by Easy Software Products, all rights reserved.
ed486911	8	*
ed486911	9	* These coded instructions, statements, and computer programs are the
bc44d920	10	* property of Apple Inc. and are protected by Federal copyright
bc44d920	11	* law. Distribution and use rights are outlined in the file "LICENSE.txt"
ed486911	12	* "LICENSE" which should have been included with this file. If this
bc44d920	13	* file is missing or damaged, see the license at "http://www.cups.org/".
ed486911	14	*
	15	* This file is subject to the Apple OS-Developed Software exception.
	16	*
	17	* Contents:
	18	*
09a101d6	19	* backendDrainOutput() - Drain pending print data to the device.
09a101d6	20	* backendRunLoop() - Read and write print and back-channel data.
c8fef167 MS	21	* backendWaitLoop() - Wait for input from stdin while handling
c8fef167 MS	22	* side-channel queries.
ed486911	23	*/
	24
	25	/*
	26	* Include necessary headers.
	27	*/
	28
	29	#include "backend-private.h"
568fa3fa	30	#include <limits.h>
d09495fa	31	#ifdef __hpux
	32	# include <sys/time.h>
	33	#else
	34	# include <sys/select.h>
	35	#endif /* __hpux */
ed486911	36
ed486911	37
09a101d6	38	/*
	39	* 'backendDrainOutput()' - Drain pending print data to the device.
	40	*/
	41
	42	int /* O - 0 on success, -1 on error */
	43	backendDrainOutput(int print_fd, /* I - Print file descriptor */
	44	int device_fd) /* I - Device file descriptor */
	45	{
	46	int nfds; /* Maximum file descriptor value + 1 */
	47	fd_set input; /* Input set for reading */
	48	ssize_t print_bytes, /* Print bytes read */
	49	bytes; /* Bytes written */
	50	char print_buffer[8192], /* Print data buffer */
	51	print_ptr; / Pointer into print data buffer */
	52	struct timeval timeout; /* Timeout for read... */
	53
	54
	55	fprintf(stderr, "DEBUG: backendDrainOutput(print_fd=%d, device_fd=%d)\n",
	56	print_fd, device_fd);
	57
	58	/*
	59	* Figure out the maximum file descriptor value to use with select()...
	60	*/
	61
	62	nfds = (print_fd > device_fd ? print_fd : device_fd) + 1;
	63
	64	/*
	65	* Now loop until we are out of data from print_fd...
	66	*/
	67
	68	for (;;)
	69	{
	70	/*
	71	* Use select() to determine whether we have data to copy around...
	72	*/
	73
	74	FD_ZERO(&input);
	75	FD_SET(print_fd, &input);
	76
	77	timeout.tv_sec = 0;
	78	timeout.tv_usec = 0;
	79
	80	if (select(nfds, &input, NULL, NULL, &timeout) < 0)
	81	return (-1);
	82
	83	if (!FD_ISSET(print_fd, &input))
	84	return (0);
	85
	86	if ((print_bytes = read(print_fd, print_buffer,
	87	sizeof(print_buffer))) < 0)
	88	{
	89	/*
	90	* Read error - bail if we don't see EAGAIN or EINTR...
	91	*/
	92
	93	if (errno != EAGAIN \|\| errno != EINTR)
	94	{
0837b7e8	95	_cupsLangPrintError("ERROR", _("Unable to read print data"));
09a101d6	96	return (-1);
	97	}
	98
	99	print_bytes = 0;
	100	}
	101	else if (print_bytes == 0)
	102	{
	103	/*
	104	* End of file, return...
	105	*/
	106
	107	return (0);
	108	}
	109
	110	fprintf(stderr, "DEBUG: Read %d bytes of print data...\n",
	111	(int)print_bytes);
	112
	113	for (print_ptr = print_buffer; print_bytes > 0;)
	114	{
	115	if ((bytes = write(device_fd, print_ptr, print_bytes)) < 0)
	116	{
	117	/*
	118	* Write error - bail if we don't see an error we can retry...
	119	*/
	120
	121	if (errno != ENOSPC && errno != ENXIO && errno != EAGAIN &&
	122	errno != EINTR && errno != ENOTTY)
	123	{
0837b7e8	124	_cupsLangPrintError("ERROR", _("Unable to write print data"));
09a101d6	125	return (-1);
	126	}
	127	}
	128	else
	129	{
	130	fprintf(stderr, "DEBUG: Wrote %d bytes of print data...\n", (int)bytes);
	131
	132	print_bytes -= bytes;
	133	print_ptr += bytes;
	134	}
	135	}
	136	}
	137	}
	138
	139
ed486911	140	/*
	141	* 'backendRunLoop()' - Read and write print and back-channel data.
	142	*/
	143
	144	ssize_t /* O - Total bytes on success, -1 on error */
f7deaa1a	145	backendRunLoop(
c8fef167 MS	146	int print_fd, /* I - Print file descriptor */
	147	int device_fd, /* I - Device file descriptor */
	148	int snmp_fd, /* I - SNMP socket or -1 if none */
	149	http_addr_t addr, / I - Address of device */
	150	int use_bc, /* I - Use back-channel? */
	151	int update_state, /* I - Update printer-state-reasons? */
	152	_cups_sccb_t side_cb) /* I - Side-channel callback */
ed486911	153	{
	154	int nfds; /* Maximum file descriptor value + 1 */
	155	fd_set input, /* Input set for reading */
	156	output; /* Output set for writing */
	157	ssize_t print_bytes, /* Print bytes read */
	158	bc_bytes, /* Backchannel bytes read */
	159	total_bytes, /* Total bytes written */
	160	bytes; /* Bytes written */
	161	int paperout; /* "Paper out" status */
8ca02f3c	162	int offline; /* "Off-line" status */
ed486911	163	char print_buffer[8192], /* Print data buffer */
	164	print_ptr, / Pointer into print data buffer */
	165	bc_buffer[1024]; /* Back-channel data buffer */
568fa3fa MS	166	struct timeval timeout; /* Timeout for select() */
	167	time_t curtime, /* Current time */
	168	snmp_update = 0;
ed486911	169	#if defined(HAVE_SIGACTION) && !defined(HAVE_SIGSET)
	170	struct sigaction action; /* Actions for POSIX signals */
	171	#endif /* HAVE_SIGACTION && !HAVE_SIGSET */
	172
	173
c0e1af83	174	fprintf(stderr,
568fa3fa MS	175	"DEBUG: backendRunLoop(print_fd=%d, device_fd=%d, snmp_fd=%d, "
	176	"addr=%p, use_bc=%d, side_cb=%p)\n",
	177	print_fd, device_fd, snmp_fd, addr, use_bc, side_cb);
8ca02f3c	178
ed486911	179	/*
	180	* If we are printing data from a print driver on stdin, ignore SIGTERM
	181	* so that the driver can finish out any page data, e.g. to eject the
	182	* current page. We only do this for stdin printing as otherwise there
	183	* is no way to cancel a raw print job...
	184	*/
	185
	186	if (!print_fd)
	187	{
	188	#ifdef HAVE_SIGSET /* Use System V signals over POSIX to avoid bugs */
	189	sigset(SIGTERM, SIG_IGN);
	190	#elif defined(HAVE_SIGACTION)
	191	memset(&action, 0, sizeof(action));
	192
	193	sigemptyset(&action.sa_mask);
	194	action.sa_handler = SIG_IGN;
	195	sigaction(SIGTERM, &action, NULL);
	196	#else
	197	signal(SIGTERM, SIG_IGN);
	198	#endif /* HAVE_SIGSET */
	199	}
4e6f60f0 MS	200	else if (print_fd < 0)
	201	{
	202	/*
	203	* Copy print data from stdin, but don't mess with the signal handlers...
	204	*/
	205
	206	print_fd = 0;
	207	}
ed486911	208
	209	/*
	210	* Figure out the maximum file descriptor value to use with select()...
	211	*/
	212
	213	nfds = (print_fd > device_fd ? print_fd : device_fd) + 1;
	214
	215	/*
	216	* Now loop until we are out of data from print_fd...
	217	*/
	218
b94498cf	219	for (print_bytes = 0, print_ptr = print_buffer, offline = -1,
b94498cf	220	paperout = -1, total_bytes = 0;;)
ed486911	221	{
	222	/*
	223	* Use select() to determine whether we have data to copy around...
	224	*/
	225
	226	FD_ZERO(&input);
	227	if (!print_bytes)
	228	FD_SET(print_fd, &input);
	229	if (use_bc)
	230	FD_SET(device_fd, &input);
dd1abb6b	231	if (!print_bytes && side_cb)
f7deaa1a	232	FD_SET(CUPS_SC_FD, &input);
ed486911	233
ed486911	234	FD_ZERO(&output);
91c84a35	235	if (print_bytes \|\| (!use_bc && !side_cb))
ed486911	236	FD_SET(device_fd, &output);
ed486911	237
f7deaa1a	238	if (use_bc \|\| side_cb)
8ca02f3c	239	{
568fa3fa MS	240	timeout.tv_sec = 5;
	241	timeout.tv_usec = 0;
	242
	243	if (select(nfds, &input, &output, NULL, &timeout) < 0)
8ca02f3c	244	{
	245	/*
	246	* Pause printing to clear any pending errors...
	247	*/
	248
ef55b745	249	if (errno == ENXIO && offline != 1 && update_state)
8ca02f3c	250	{
c5571a1d	251	fputs("STATE: +offline-report\n", stderr);
0837b7e8 MS	252	_cupsLangPrintFilter(stderr, "INFO",
0837b7e8 MS	253	_("Printer is not currently connected."));
8ca02f3c	254	offline = 1;
8ca02f3c	255	}
b94498cf	256	else if (errno == EINTR && total_bytes == 0)
	257	{
	258	fputs("DEBUG: Received an interrupt before any bytes were "
c8fef167	259	"written, aborting.\n", stderr);
b94498cf	260	return (0);
b94498cf	261	}
8ca02f3c	262
	263	sleep(1);
	264	continue;
	265	}
	266	}
ed486911	267
f7deaa1a	268	/*
	269	* Check if we have a side-channel request ready...
	270	*/
	271
	272	if (side_cb && FD_ISSET(CUPS_SC_FD, &input))
dd1abb6b MS	273	{
	274	/*
	275	* Do the side-channel request, then start back over in the select
	276	* loop since it may have read from print_fd...
	277	*/
	278
18ecb428 MS	279	if ((*side_cb)(print_fd, device_fd, snmp_fd, addr, use_bc))
18ecb428 MS	280	side_cb = NULL;
dd1abb6b MS	281	continue;
dd1abb6b MS	282	}
f7deaa1a	283
ed486911	284	/*
	285	* Check if we have back-channel data ready...
	286	*/
	287
	288	if (FD_ISSET(device_fd, &input))
	289	{
	290	if ((bc_bytes = read(device_fd, bc_buffer, sizeof(bc_buffer))) > 0)
	291	{
	292	fprintf(stderr,
4d301e69	293	"DEBUG: Received " CUPS_LLFMT " bytes of back-channel data\n",
ed486911	294	CUPS_LLCAST bc_bytes);
	295	cupsBackChannelWrite(bc_buffer, bc_bytes, 1.0);
	296	}
4b3f67ff MS	297	else if (bc_bytes < 0 && errno != EAGAIN && errno != EINTR)
	298	{
	299	fprintf(stderr, "DEBUG: Error reading back-channel data: %s\n",
	300	strerror(errno));
	301	use_bc = 0;
	302	}
7cf5915e MS	303	else if (bc_bytes == 0)
7cf5915e MS	304	use_bc = 0;
ed486911	305	}
	306
	307	/*
	308	* Check if we have print data ready...
	309	*/
	310
	311	if (FD_ISSET(print_fd, &input))
	312	{
	313	if ((print_bytes = read(print_fd, print_buffer,
	314	sizeof(print_buffer))) < 0)
	315	{
	316	/*
	317	* Read error - bail if we don't see EAGAIN or EINTR...
	318	*/
	319
	320	if (errno != EAGAIN \|\| errno != EINTR)
	321	{
0837b7e8	322	_cupsLangPrintError("ERROR", _("Unable to read print data"));
ed486911	323	return (-1);
	324	}
	325
	326	print_bytes = 0;
	327	}
	328	else if (print_bytes == 0)
	329	{
	330	/*
	331	* End of file, break out of the loop...
	332	*/
	333
	334	break;
	335	}
	336
	337	print_ptr = print_buffer;
8ca02f3c	338
	339	fprintf(stderr, "DEBUG: Read %d bytes of print data...\n",
	340	(int)print_bytes);
ed486911	341	}
	342
	343	/*
	344	* Check if the device is ready to receive data and we have data to
	345	* send...
	346	*/
	347
	348	if (print_bytes && FD_ISSET(device_fd, &output))
	349	{
	350	if ((bytes = write(device_fd, print_ptr, print_bytes)) < 0)
	351	{
	352	/*
	353	* Write error - bail if we don't see an error we can retry...
	354	*/
	355
	356	if (errno == ENOSPC)
	357	{
ef55b745	358	if (paperout != 1 && update_state)
ed486911	359	{
c5571a1d	360	fputs("STATE: +media-empty-warning\n", stderr);
0837b7e8	361	fputs("DEBUG: Out of paper\n", stderr);
ed486911	362	paperout = 1;
	363	}
	364	}
8ca02f3c	365	else if (errno == ENXIO)
8ca02f3c	366	{
ef55b745	367	if (offline != 1 && update_state)
8ca02f3c	368	{
c5571a1d	369	fputs("STATE: +offline-report\n", stderr);
0837b7e8 MS	370	_cupsLangPrintFilter(stderr, "INFO",
0837b7e8 MS	371	_("Printer is not currently connected."));
8ca02f3c	372	offline = 1;
	373	}
	374	}
ed486911	375	else if (errno != EAGAIN && errno != EINTR && errno != ENOTTY)
ed486911	376	{
0837b7e8	377	_cupsLangPrintError("ERROR", _("Unable to write print data"));
ed486911	378	return (-1);
	379	}
	380	}
	381	else
	382	{
ef55b745	383	if (paperout && update_state)
ed486911	384	{
c5571a1d	385	fputs("STATE: -media-empty-warning\n", stderr);
ed486911	386	paperout = 0;
	387	}
	388
ef55b745	389	if (offline && update_state)
8ca02f3c	390	{
c5571a1d	391	fputs("STATE: -offline-report\n", stderr);
0837b7e8	392	_cupsLangPrintFilter(stderr, "INFO", _("Printer is now connected."));
8ca02f3c	393	offline = 0;
	394	}
	395
	396	fprintf(stderr, "DEBUG: Wrote %d bytes of print data...\n", (int)bytes);
ed486911	397
	398	print_bytes -= bytes;
	399	print_ptr += bytes;
	400	total_bytes += bytes;
	401	}
	402	}
568fa3fa MS	403
	404	/*
	405	* Do SNMP updates periodically...
	406	*/
	407
	408	if (snmp_fd >= 0 && time(&curtime) >= snmp_update)
	409	{
	410	if (backendSNMPSupplies(snmp_fd, addr, NULL, NULL))
	411	snmp_update = INT_MAX;
	412	else
	413	snmp_update = curtime + 5;
	414	}
ed486911	415	}
	416
	417	/*
	418	* Return with success...
	419	*/
	420
	421	return (total_bytes);
	422	}
	423
	424
	425	/*
c8fef167 MS	426	* 'backendWaitLoop()' - Wait for input from stdin while handling side-channel
	427	* queries.
	428	*/
	429
	430	int /* O - 1 if data is ready, 0 if not */
	431	backendWaitLoop(
	432	int snmp_fd, /* I - SNMP socket or -1 if none */
	433	http_addr_t addr, / I - Address of device */
f14324a7	434	int use_bc, /* I - Use back-channel? */
c8fef167 MS	435	_cups_sccb_t side_cb) /* I - Side-channel callback */
	436	{
	437	fd_set input; /* Input set for reading */
	438	time_t curtime, /* Current time */
f99f3698	439	snmp_update = 0; /* Last SNMP status update */
c8fef167 MS	440
	441
	442	fprintf(stderr, "DEBUG: backendWaitLoop(snmp_fd=%d, addr=%p, side_cb=%p)\n",
	443	snmp_fd, addr, side_cb);
	444
	445	/*
	446	* Now loop until we receive data from stdin...
	447	*/
	448
	449	for (;;)
	450	{
	451	/*
	452	* Use select() to determine whether we have data to copy around...
	453	*/
	454
	455	FD_ZERO(&input);
	456	FD_SET(0, &input);
	457	if (side_cb)
	458	FD_SET(CUPS_SC_FD, &input);
	459
	460	if (select(CUPS_SC_FD + 1, &input, NULL, NULL, NULL) < 0)
	461	{
	462	/*
	463	* Pause printing to clear any pending errors...
	464	*/
	465
	466	if (errno == EINTR)
	467	{
	468	fputs("DEBUG: Received an interrupt before any bytes were "
	469	"written, aborting.\n", stderr);
	470	return (0);
	471	}
	472
	473	sleep(1);
	474	continue;
	475	}
	476
	477	/*
	478	* Check for input on stdin...
	479	*/
	480
	481	if (FD_ISSET(0, &input))
	482	break;
	483
	484	/*
	485	* Check if we have a side-channel request ready...
	486	*/
	487
	488	if (side_cb && FD_ISSET(CUPS_SC_FD, &input))
	489	{
	490	/*
	491	* Do the side-channel request, then start back over in the select
	492	* loop since it may have read from print_fd...
	493	*/
	494
f14324a7	495	if ((*side_cb)(0, -1, snmp_fd, addr, use_bc))
c8fef167 MS	496	side_cb = NULL;
	497	continue;
	498	}
	499
	500	/*
	501	* Do SNMP updates periodically...
	502	*/
	503
	504	if (snmp_fd >= 0 && time(&curtime) >= snmp_update)
	505	{
	506	if (backendSNMPSupplies(snmp_fd, addr, NULL, NULL))
	507	snmp_update = INT_MAX;
	508	else
	509	snmp_update = curtime + 5;
	510	}
	511	}
	512
	513	/*
	514	* Return with success...
	515	*/
	516
	517	return (1);
	518	}
	519
	520
	521	/*
	522	* End of "$Id: runloop.c 9565 2011-02-23 00:08:08Z mike $".
ed486911	523	*/