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

/*
 * "$Id: runloop.c 6834 2007-08-22 18:29:25Z mike $"
 *
 *   Common run loop APIs for the Common UNIX Printing System (CUPS).
 *
 *   Copyright 2007-2008 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.
 */

/*
 * 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)
      {
	perror("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)
	{
	  _cupsLangPrintf(stderr, _("ERROR: Unable to write print data: %s\n"),
			  strerror(errno));
	  return (-1);
	}
      }
      else
      {
        fprintf(stderr, "DEBUG: Wrote %d bytes of print data...\n", (int)bytes);

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


/*
 * 'backendNetworkSideCB()' - Handle common network side-channel commands.
 */

void
backendNetworkSideCB(
    int         print_fd,		/* I - Print file or -1 */
    int         device_fd,		/* I - Device file or -1 */
    int         snmp_fd,		/* I - SNMP socket */
    http_addr_t *addr,			/* I - Address of device */
    int         use_bc)			/* I - Use back-channel data? */
{
  cups_sc_command_t	command;	/* Request command */
  cups_sc_status_t	status;		/* Request/response status */
  char			data[2048];	/* Request/response data */
  int			datalen;	/* Request/response data size */
  const char		*device_id;	/* 1284DEVICEID env var */


  datalen = sizeof(data);

  if (cupsSideChannelRead(&command, &status, data, &datalen, 1.0))
  {
    _cupsLangPuts(stderr, _("WARNING: Failed to read side-channel request!\n"));
    return;
  }

  switch (command)
  {
    case CUPS_SC_CMD_DRAIN_OUTPUT :
       /*
        * Our sockets disable the Nagle algorithm and data is sent immediately.
	*/

        if (backendDrainOutput(print_fd, device_fd))
	  status = CUPS_SC_STATUS_IO_ERROR;
	else 
          status = CUPS_SC_STATUS_OK;

	datalen = 0;
        break;

    case CUPS_SC_CMD_GET_BIDI :
        data[0] = use_bc;
        datalen = 1;
        break;

    case CUPS_SC_CMD_GET_DEVICE_ID :
        if ((device_id = getenv("1284DEVICEID")) != NULL)
	{
	  strlcpy(data, device_id, sizeof(data));
	  datalen = (int)strlen(data);
	  break;
	}

    default :
        status  = CUPS_SC_STATUS_NOT_IMPLEMENTED;
	datalen = 0;
	break;
  }

  cupsSideChannelWrite(command, status, data, datalen, 1.0);
}


/*
 * '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? */
    void        (*side_cb)(int, int, int, http_addr_t *, int))
					/* 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 */
  }

 /*
  * 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 (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)
	{
	  fputs("STATE: +offline-error\n", stderr);
	  _cupsLangPuts(stderr, _("INFO: Printer is currently offline.\n"));
	  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))
      (*side_cb)(print_fd, device_fd, snmp_fd, addr, use_bc);

   /*
    * 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);
      }
    }

   /*
    * 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)
	{
	  perror("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)
	  {
	    fputs("STATE: +media-empty-error\n", stderr);
	    _cupsLangPuts(stderr, _("ERROR: Out of paper!\n"));
	    paperout = 1;
	  }
        }
	else if (errno == ENXIO)
	{
	  if (offline != 1)
	  {
	    fputs("STATE: +offline-error\n", stderr);
	    _cupsLangPuts(stderr, _("INFO: Printer is currently off-line.\n"));
	    offline = 1;
	  }
	}
	else if (errno != EAGAIN && errno != EINTR && errno != ENOTTY)
	{
	  fprintf(stderr, _("ERROR: Unable to write print data: %s\n"),
	          strerror(errno));
	  return (-1);
	}
      }
      else
      {
        if (paperout)
	{
	  fputs("STATE: -media-empty-error\n", stderr);
	  paperout = 0;
	}

	if (offline)
	{
	  fputs("STATE: -offline-error\n", stderr);
	  _cupsLangPuts(stderr, _("INFO: Printer is now online.\n"));
	  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);
}


/*
 * End of "$Id: runloop.c 6834 2007-08-22 18:29:25Z mike $".
 */
Commit	Line	Data
ed486911	1	/*
2e4ff8af	2	* "$Id: runloop.c 6834 2007-08-22 18:29:25Z mike $"
ed486911	3	*
09a101d6	4	* Common run loop APIs for the Common UNIX Printing System (CUPS).
ed486911	5	*
91c84a35	6	* Copyright 2007-2008 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.
ed486911	21	*/
	22
	23	/*
	24	* Include necessary headers.
	25	*/
	26
	27	#include "backend-private.h"
568fa3fa	28	#include <limits.h>
d09495fa	29	#ifdef __hpux
	30	# include <sys/time.h>
	31	#else
	32	# include <sys/select.h>
	33	#endif /* __hpux */
ed486911	34
ed486911	35
09a101d6	36	/*
	37	* 'backendDrainOutput()' - Drain pending print data to the device.
	38	*/
	39
	40	int /* O - 0 on success, -1 on error */
	41	backendDrainOutput(int print_fd, /* I - Print file descriptor */
	42	int device_fd) /* I - Device file descriptor */
	43	{
	44	int nfds; /* Maximum file descriptor value + 1 */
	45	fd_set input; /* Input set for reading */
	46	ssize_t print_bytes, /* Print bytes read */
	47	bytes; /* Bytes written */
	48	char print_buffer[8192], /* Print data buffer */
	49	print_ptr; / Pointer into print data buffer */
	50	struct timeval timeout; /* Timeout for read... */
	51
	52
	53	fprintf(stderr, "DEBUG: backendDrainOutput(print_fd=%d, device_fd=%d)\n",
	54	print_fd, device_fd);
	55
	56	/*
	57	* Figure out the maximum file descriptor value to use with select()...
	58	*/
	59
	60	nfds = (print_fd > device_fd ? print_fd : device_fd) + 1;
	61
	62	/*
	63	* Now loop until we are out of data from print_fd...
	64	*/
	65
	66	for (;;)
	67	{
	68	/*
	69	* Use select() to determine whether we have data to copy around...
	70	*/
	71
	72	FD_ZERO(&input);
	73	FD_SET(print_fd, &input);
	74
	75	timeout.tv_sec = 0;
	76	timeout.tv_usec = 0;
	77
	78	if (select(nfds, &input, NULL, NULL, &timeout) < 0)
	79	return (-1);
	80
	81	if (!FD_ISSET(print_fd, &input))
	82	return (0);
	83
	84	if ((print_bytes = read(print_fd, print_buffer,
	85	sizeof(print_buffer))) < 0)
	86	{
	87	/*
	88	* Read error - bail if we don't see EAGAIN or EINTR...
	89	*/
	90
	91	if (errno != EAGAIN \|\| errno != EINTR)
	92	{
	93	perror("ERROR: Unable to read print data");
	94	return (-1);
	95	}
	96
	97	print_bytes = 0;
	98	}
	99	else if (print_bytes == 0)
100	{
101	/*
102	* End of file, return...
103	*/
104
105	return (0);
106	}
107
108	fprintf(stderr, "DEBUG: Read %d bytes of print data...\n",
109	(int)print_bytes);
110
111	for (print_ptr = print_buffer; print_bytes > 0;)
112	{
113	if ((bytes = write(device_fd, print_ptr, print_bytes)) < 0)
114	{
115	/*
116	* Write error - bail if we don't see an error we can retry...
117	*/
118
119	if (errno != ENOSPC && errno != ENXIO && errno != EAGAIN &&
120	errno != EINTR && errno != ENOTTY)
121	{
db1f069b MS	122	_cupsLangPrintf(stderr, _("ERROR: Unable to write print data: %s\n"),
db1f069b MS	123	strerror(errno));
09a101d6	124	return (-1);
	125	}
	126	}
	127	else
	128	{
	129	fprintf(stderr, "DEBUG: Wrote %d bytes of print data...\n", (int)bytes);
	130
	131	print_bytes -= bytes;
	132	print_ptr += bytes;
	133	}
	134	}
	135	}
	136	}
	137
	138
568fa3fa MS	139	/*
	140	* 'backendNetworkSideCB()' - Handle common network side-channel commands.
	141	*/
	142
	143	void
	144	backendNetworkSideCB(
	145	int print_fd, /* I - Print file or -1 */
	146	int device_fd, /* I - Device file or -1 */
	147	int snmp_fd, /* I - SNMP socket */
	148	http_addr_t addr, / I - Address of device */
	149	int use_bc) /* I - Use back-channel data? */
	150	{
	151	cups_sc_command_t command; /* Request command */
	152	cups_sc_status_t status; /* Request/response status */
	153	char data[2048]; /* Request/response data */
	154	int datalen; /* Request/response data size */
	155	const char device_id; / 1284DEVICEID env var */
	156
	157
	158	datalen = sizeof(data);
	159
	160	if (cupsSideChannelRead(&command, &status, data, &datalen, 1.0))
	161	{
	162	_cupsLangPuts(stderr, _("WARNING: Failed to read side-channel request!\n"));
	163	return;
	164	}
	165
	166	switch (command)
	167	{
	168	case CUPS_SC_CMD_DRAIN_OUTPUT :
	169	/*
	170	* Our sockets disable the Nagle algorithm and data is sent immediately.
	171	*/
	172
	173	if (backendDrainOutput(print_fd, device_fd))
	174	status = CUPS_SC_STATUS_IO_ERROR;
	175	else
	176	status = CUPS_SC_STATUS_OK;
	177
	178	datalen = 0;
	179	break;
	180
	181	case CUPS_SC_CMD_GET_BIDI :
	182	data[0] = use_bc;
	183	datalen = 1;
	184	break;
	185
	186	case CUPS_SC_CMD_GET_DEVICE_ID :
	187	if ((device_id = getenv("1284DEVICEID")) != NULL)
	188	{
	189	strlcpy(data, device_id, sizeof(data));
	190	datalen = (int)strlen(data);
	191	break;
	192	}
	193
	194	default :
	195	status = CUPS_SC_STATUS_NOT_IMPLEMENTED;
	196	datalen = 0;
	197	break;
	198	}
	199
	200	cupsSideChannelWrite(command, status, data, datalen, 1.0);
	201	}
	202
203
ed486911	204	/*
	205	* 'backendRunLoop()' - Read and write print and back-channel data.
	206	*/
	207
	208	ssize_t /* O - Total bytes on success, -1 on error */
f7deaa1a	209	backendRunLoop(
568fa3fa MS	210	int print_fd, /* I - Print file descriptor */
	211	int device_fd, /* I - Device file descriptor */
	212	int snmp_fd, /* I - SNMP socket or -1 if none */
	213	http_addr_t addr, / I - Address of device */
	214	int use_bc, /* I - Use back-channel? */
	215	void (side_cb)(int, int, int, http_addr_t , int))
	216	/* I - Side-channel callback */
ed486911	217	{
	218	int nfds; /* Maximum file descriptor value + 1 */
	219	fd_set input, /* Input set for reading */
	220	output; /* Output set for writing */
	221	ssize_t print_bytes, /* Print bytes read */
	222	bc_bytes, /* Backchannel bytes read */
	223	total_bytes, /* Total bytes written */
	224	bytes; /* Bytes written */
	225	int paperout; /* "Paper out" status */
8ca02f3c	226	int offline; /* "Off-line" status */
ed486911	227	char print_buffer[8192], /* Print data buffer */
	228	print_ptr, / Pointer into print data buffer */
	229	bc_buffer[1024]; /* Back-channel data buffer */
568fa3fa MS	230	struct timeval timeout; /* Timeout for select() */
	231	time_t curtime, /* Current time */
	232	snmp_update = 0;
ed486911	233	#if defined(HAVE_SIGACTION) && !defined(HAVE_SIGSET)
	234	struct sigaction action; /* Actions for POSIX signals */
	235	#endif /* HAVE_SIGACTION && !HAVE_SIGSET */
	236
	237
c0e1af83	238	fprintf(stderr,
568fa3fa MS	239	"DEBUG: backendRunLoop(print_fd=%d, device_fd=%d, snmp_fd=%d, "
	240	"addr=%p, use_bc=%d, side_cb=%p)\n",
	241	print_fd, device_fd, snmp_fd, addr, use_bc, side_cb);
8ca02f3c	242
ed486911	243	/*
	244	* If we are printing data from a print driver on stdin, ignore SIGTERM
	245	* so that the driver can finish out any page data, e.g. to eject the
	246	* current page. We only do this for stdin printing as otherwise there
	247	* is no way to cancel a raw print job...
	248	*/
	249
	250	if (!print_fd)
	251	{
	252	#ifdef HAVE_SIGSET /* Use System V signals over POSIX to avoid bugs */
	253	sigset(SIGTERM, SIG_IGN);
	254	#elif defined(HAVE_SIGACTION)
	255	memset(&action, 0, sizeof(action));
	256
	257	sigemptyset(&action.sa_mask);
	258	action.sa_handler = SIG_IGN;
	259	sigaction(SIGTERM, &action, NULL);
	260	#else
	261	signal(SIGTERM, SIG_IGN);
	262	#endif /* HAVE_SIGSET */
	263	}
	264
	265	/*
	266	* Figure out the maximum file descriptor value to use with select()...
	267	*/
	268
	269	nfds = (print_fd > device_fd ? print_fd : device_fd) + 1;
	270
	271	/*
	272	* Now loop until we are out of data from print_fd...
	273	*/
	274
b94498cf	275	for (print_bytes = 0, print_ptr = print_buffer, offline = -1,
b94498cf	276	paperout = -1, total_bytes = 0;;)
ed486911	277	{
	278	/*
	279	* Use select() to determine whether we have data to copy around...
	280	*/
	281
	282	FD_ZERO(&input);
	283	if (!print_bytes)
	284	FD_SET(print_fd, &input);
	285	if (use_bc)
	286	FD_SET(device_fd, &input);
f7deaa1a	287	if (side_cb)
f7deaa1a	288	FD_SET(CUPS_SC_FD, &input);
ed486911	289
ed486911	290	FD_ZERO(&output);
91c84a35	291	if (print_bytes \|\| (!use_bc && !side_cb))
ed486911	292	FD_SET(device_fd, &output);
ed486911	293
f7deaa1a	294	if (use_bc \|\| side_cb)
8ca02f3c	295	{
568fa3fa MS	296	timeout.tv_sec = 5;
	297	timeout.tv_usec = 0;
	298
	299	if (select(nfds, &input, &output, NULL, &timeout) < 0)
8ca02f3c	300	{
	301	/*
	302	* Pause printing to clear any pending errors...
	303	*/
	304
b94498cf	305	if (errno == ENXIO && offline != 1)
8ca02f3c	306	{
8ca02f3c	307	fputs("STATE: +offline-error\n", stderr);
080811b1	308	_cupsLangPuts(stderr, _("INFO: Printer is currently offline.\n"));
8ca02f3c	309	offline = 1;
8ca02f3c	310	}
b94498cf	311	else if (errno == EINTR && total_bytes == 0)
	312	{
	313	fputs("DEBUG: Received an interrupt before any bytes were "
	314	"written, aborting!\n", stderr);
	315	return (0);
	316	}
8ca02f3c	317
	318	sleep(1);
	319	continue;
	320	}
	321	}
ed486911	322
f7deaa1a	323	/*
	324	* Check if we have a side-channel request ready...
	325	*/
	326
	327	if (side_cb && FD_ISSET(CUPS_SC_FD, &input))
568fa3fa	328	(*side_cb)(print_fd, device_fd, snmp_fd, addr, use_bc);
f7deaa1a	329
ed486911	330	/*
	331	* Check if we have back-channel data ready...
	332	*/
	333
	334	if (FD_ISSET(device_fd, &input))
	335	{
	336	if ((bc_bytes = read(device_fd, bc_buffer, sizeof(bc_buffer))) > 0)
	337	{
	338	fprintf(stderr,
	339	"DEBUG: Received " CUPS_LLFMT " bytes of back-channel data!\n",
	340	CUPS_LLCAST bc_bytes);
	341	cupsBackChannelWrite(bc_buffer, bc_bytes, 1.0);
	342	}
	343	}
	344
	345	/*
	346	* Check if we have print data ready...
	347	*/
	348
	349	if (FD_ISSET(print_fd, &input))
	350	{
	351	if ((print_bytes = read(print_fd, print_buffer,
	352	sizeof(print_buffer))) < 0)
	353	{
	354	/*
	355	* Read error - bail if we don't see EAGAIN or EINTR...
	356	*/
	357
	358	if (errno != EAGAIN \|\| errno != EINTR)
	359	{
	360	perror("ERROR: Unable to read print data");
	361	return (-1);
	362	}
	363
	364	print_bytes = 0;
	365	}
	366	else if (print_bytes == 0)
	367	{
	368	/*
	369	* End of file, break out of the loop...
	370	*/
	371
	372	break;
	373	}
	374
	375	print_ptr = print_buffer;
8ca02f3c	376
	377	fprintf(stderr, "DEBUG: Read %d bytes of print data...\n",
	378	(int)print_bytes);
ed486911	379	}
	380
	381	/*
	382	* Check if the device is ready to receive data and we have data to
	383	* send...
	384	*/
	385
	386	if (print_bytes && FD_ISSET(device_fd, &output))
	387	{
	388	if ((bytes = write(device_fd, print_ptr, print_bytes)) < 0)
	389	{
	390	/*
	391	* Write error - bail if we don't see an error we can retry...
	392	*/
	393
	394	if (errno == ENOSPC)
	395	{
b94498cf	396	if (paperout != 1)
ed486911	397	{
b86bc4cf	398	fputs("STATE: +media-empty-error\n", stderr);
db1f069b	399	_cupsLangPuts(stderr, _("ERROR: Out of paper!\n"));
ed486911	400	paperout = 1;
	401	}
	402	}
8ca02f3c	403	else if (errno == ENXIO)
8ca02f3c	404	{
b94498cf	405	if (offline != 1)
8ca02f3c	406	{
8ca02f3c	407	fputs("STATE: +offline-error\n", stderr);
db1f069b	408	_cupsLangPuts(stderr, _("INFO: Printer is currently off-line.\n"));
8ca02f3c	409	offline = 1;
	410	}
	411	}
ed486911	412	else if (errno != EAGAIN && errno != EINTR && errno != ENOTTY)
ed486911	413	{
c0e1af83	414	fprintf(stderr, _("ERROR: Unable to write print data: %s\n"),
c0e1af83	415	strerror(errno));
ed486911	416	return (-1);
	417	}
	418	}
	419	else
	420	{
	421	if (paperout)
	422	{
b86bc4cf	423	fputs("STATE: -media-empty-error\n", stderr);
ed486911	424	paperout = 0;
	425	}
	426
8ca02f3c	427	if (offline)
	428	{
	429	fputs("STATE: -offline-error\n", stderr);
080811b1	430	_cupsLangPuts(stderr, _("INFO: Printer is now online.\n"));
8ca02f3c	431	offline = 0;
	432	}
	433
	434	fprintf(stderr, "DEBUG: Wrote %d bytes of print data...\n", (int)bytes);
ed486911	435
	436	print_bytes -= bytes;
	437	print_ptr += bytes;
	438	total_bytes += bytes;
	439	}
	440	}
568fa3fa MS	441
	442	/*
	443	* Do SNMP updates periodically...
	444	*/
	445
	446	if (snmp_fd >= 0 && time(&curtime) >= snmp_update)
	447	{
	448	if (backendSNMPSupplies(snmp_fd, addr, NULL, NULL))
	449	snmp_update = INT_MAX;
	450	else
	451	snmp_update = curtime + 5;
	452	}
ed486911	453	}
	454
	455	/*
	456	* Return with success...
	457	*/
	458
	459	return (total_bytes);
	460	}
	461
	462
	463	/*
2e4ff8af	464	* End of "$Id: runloop.c 6834 2007-08-22 18:29:25Z mike $".
ed486911	465	*/