diff --git a/backend/Makefile b/backend/Makefile

index 3038682..6642016 100644

--- a/backend/Makefile

+++ b/backend/Makefile

@@ -28,6 +28,7 @@ include ../Makedefs

 RBACKENDS =	\

 		ipp \

 		lpd \

+		failover \

 		$(DNSSD_BACKEND)

 UBACKENDS =	\

 		snmp \

@@ -51,6 +52,7 @@ LIBOBJS	=	\

 OBJS	=	\

 		ipp.o \

 		lpd.o \

+		failover.o \

 		dnssd.o \

 		snmp.o \

 		socket.o \

@@ -275,6 +277,13 @@ lpd:	lpd.o ../cups/$(LIBCUPS) libbackend.a

 	echo Linking $@...

 	$(LD_CC) $(LDFLAGS) -o lpd lpd.o libbackend.a $(LIBS)

+#

+# failover

+#

+

+failover:	failover.o ../cups/$(LIBCUPS) libbackend.a

+	echo Linking $@...

+	$(LD_CC) $(LDFLAGS) -o failover failover.o libbackend.a $(LIBS)

 #

 # snmp

diff --git a/backend/failover.c b/backend/failover.c

new file mode 100644

index 0000000..9affd8f

--- /dev/null

+++ b/backend/failover.c

@@ -0,0 +1,837 @@

+/*

+ * Failover Backend for the Common UNIX Printing System (CUPS).

+ *

+ * Copyright (c) 2014, Red Hat, Inc.

+ * All rights reserved.

+ *

+ * Redistribution and use in source and binary forms, with or without

+ * modification, are permitted provided that the following conditions

+ * are met:

+ *

+ * * Redistributions of source code must retain the above copyright

+ *   notice, this list of conditions and the following disclaimer.

+ * * Redistributions in binary form must reproduce the above copyright

+ *   notice, this list of conditions and the following disclaimer in the

+ *   documentation and/or other materials provided with the distribution.

+ * * Neither the name of Red Hat, Inc. nor the names of its contributors

+ *   may be used to endorse or promote products derived from this software

+ *   without specific prior written permission.

+ *

+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS

+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT,

+ * INC.  BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY

+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE

+ * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH

+ * DAMAGE.

+ *

+ * Original version by Clark Hale, Red Hat, Inc.

+ *

+ * This backend presents a fake printer that will choose the first

+ * available printer from a list of IPP URIs.

+ *

+ * Option failover contains a comma separated list of IPP URIs.  The

+ * URIs are attempted in-order.

+ *

+ * Option failover-retries contains an integer that indicates how many

+ * times to iterate through the failover list before completely

+ * failing.

+ *

+ * Contents:

+ *   main()                   - Checks each printer in a failover list, and

+ *                              sends job data to the first available printer

+ *   move_job()               - Sends and IPP Move-Job request

+ *   check_printer()          - Checks a printer's attributes to see

+ *                              if it's enabled and accepting jobs

+ *   read_config()            - Read the backends configuration from

+ *                              options

+ *   get_printer_attributes() - Sends an IPP Get-Attributes request to

+ *                              a URI

+ *   sigterm_handler()        - Handle SIGTERM that cancels the job

+ *   password_cb()            - Password call back used to disable password

+ *                              prompt

+ */

+#include <stdlib.h>

+#include <stdio.h>

+#include <string.h>

+#include <sys/wait.h>

+#include <cups/http-private.h>

+#include <cups/http.h>

+#include "backend-private.h"

+

+/*

+ * Return Values

+ */

+typedef enum fo_state_e

+{

+  FO_PRINTER_GOOD = 0,

+  FO_PRINTER_BAD,

+  FO_PRINTER_BUSY,

+  FO_AUTH_REQUIRED

+} fo_state_t;

+

+/*

+ * Constants

+ */

+#define FAILOVER_DEFAULT_RETRIES        (3)

+#define FAILOVER_PASSWORD_RETRIES_MAX   (3)

+

+/*

+ * Local Functions

+ */

+static       int   check_printer(const char *device_uri);

+static       int   read_config(cups_array_t *printer_array, int *retries,

+                               const char *options);

+static       int   get_printer_attributes(const char *device_uri,

+                                          ipp_t **attributes);

+static       int   move_job(int jobid, const char *dest);

+static       void  sigterm_handler(int sig);

+static const char *password_cb(const char *);

+

+/*

+ * Global Variables

+ */

+static int         job_canceled = 0;     /* Job canceled */

+static char       *password = NULL;      /* password for device */

+static int         password_retries = 0;

+static const char *auth_info_required = "none";

+

+/*

+ * 'main()' - Checks each printer in a failover list, and

+ *            sends job data to the first available printer

+ * Usage:

+ *    printer-uri job-id user title copies options [file]

+ *

+ *    The printer-uri option is not used, but it still required to fit

+ *    to the backend(7) standards.

+ */

+int

+main(int argc, char *argv[])

+{

+  const char   *selected_uri = NULL;      /* URI of selected printer     */

+  const char   *tmp_device_uri;           /* Device URI to check         */

+  cups_array_t *printer_array;            /* Array of available printers */

+  int           printer_count = 0;        /* current printer array index */

+  int           retry_max = 1;            /* maximum retries before exit */

+  int           retry_count = 0;          /* current retry number        */

+  int           auth_failed_count = 0;    /* auth failures per loop      */

+  int           rc = CUPS_BACKEND_OK;

+#if defined(HAVE_SIGACTION) && !defined(HAVE_SIGSET)

+  struct        sigaction action;       /* Actions for POSIX signals */

+#endif /* HAVE_SIGACTION && !HAVE_SIGSET */

+

+ /*

+  * Check args

+  */

+  if (argc == 1)

+  {

+   /*

+    * print out discovery data

+    */

+    char *backendName;

+

+    if ((backendName = strrchr(argv[0], '/')) != NULL)

+      backendName++;

+    else

+      backendName = argv[0];

+

+    _cupsLangPrintf(stderr,"network %s \"Unknown\" \"%s (%s)\"\n",

+                    backendName,

+                    _cupsLangString(cupsLangDefault(), _("Failover Printer")),

+                    backendName);

+

+    return (CUPS_BACKEND_OK);

+  }

+  else if (argc < 6)

+  {

+    _cupsLangPrintf(stderr,

+                    _("Usage: %s job-id user title copies options [file]"),

+                    argv[0]);

+    return (CUPS_BACKEND_STOP);

+  }

+

+  fprintf(stderr, "DEBUG: Failover backend starting up.\n");

+

+ /*

+  * Don't buffer status messages

+  */

+  setbuf(stderr, NULL);

+

+ /*

+  * Ignore SIGPIPE and catch SIGTERM signals...

+  */

+#ifdef HAVE_SIGSET

+  sigset(SIGPIPE, SIG_IGN);

+  sigset(SIGTERM, sigterm_handler);

+#elif defined(HAVE_SIGACTION)

+  memset(&action, 0, sizeof(action));

+  action.sa_handler = SIG_IGN;

+  sigaction(SIGPIPE, &action, NULL);

+

+  sigemptyset(&action.sa_mask);

+  sigaddset(&action.sa_mask, SIGTERM);

+  action.sa_handler = sigterm_handler;

+  sigaction(SIGTERM, &action, NULL);

+#else

+  signal(SIGPIPE, SIG_IGN);

+  signal(SIGTERM, sigterm_handler);

+#endif /* HAVE_SIGSET */

+

+  printer_array = cupsArrayNew(NULL, NULL);

+

+ /*

+  * Read Configuration

+  */

+  if ((rc = read_config(printer_array, &retry_max,

+                        argv[5])) != CUPS_BACKEND_OK)

+  {

+    fprintf(stderr, "ERROR: Failed to read configuration options!\n");

+    goto cleanup;

+  }

+

+ /*

+  * Main Retry Loop

+  */

+  for (retry_count = 0; retry_count < retry_max; retry_count++)

+  {

+    fprintf(stderr, "DEBUG: Retry loop #%d\n", retry_count + 1);

+

+   /*

+    * Reset Counters

+    */

+    printer_count = 0;

+    auth_failed_count = 0;

+

+    tmp_device_uri = (char *)cupsArrayFirst(printer_array);

+

+    do

+    {

+      if (job_canceled)

+      {

+        fprintf(stderr, "DEBUG: Job Canceled\n");

+        goto cleanup;

+      }

+

+      fprintf(stderr,"DEBUG: Checking printer #%d: %s\n",

+              printer_count+1, tmp_device_uri);

+

+      rc = check_printer(tmp_device_uri);

+

+      // Printer is available and not busy.

+      if ( rc == FO_PRINTER_GOOD )

+      {

+        selected_uri = tmp_device_uri;

+        break;

+      }

+      // Printer is busy

+      else if (rc == FO_PRINTER_BUSY)

+      {

+        fprintf(stderr, "DEBUG: Waiting for job to complete.\n");

+        sleep(2);

+        continue;

+      }

+      // Authorization is required to access the printer.

+      else if (rc == FO_AUTH_REQUIRED)

+      {

+        auth_failed_count++;

+        fprintf(stderr, "DEBUG: auth_failed_count = %d\n", auth_failed_count);

+      }

+      // Printer is stopped or not accepting jobs

+      else

+      {

+        if (!printer_count)

+          fprintf(stderr, "INFO: Primary Printer, %s, not available.  "

+                  "Attempting Failovers...\n",

+                  tmp_device_uri);

+        else

+          fprintf(stderr, "INFO: Failover Printer, %s, not available.  "

+                  "Attempting Failovers..\n",

+                  tmp_device_uri);

+        printer_count++;

+        tmp_device_uri = (char *)cupsArrayNext(printer_array);

+      }

+    } while (tmp_device_uri != NULL);

+

+    if (selected_uri && !printer_count)

+      fprintf(stderr, "STATE: -primary-printer-failed\n");

+    else

+      fprintf(stderr, "STATE: +primary-printer-failed\n");

+

+    if (job_canceled)

+    {

+      fprintf(stderr, "DEBUG: Job Canceled\n");

+      goto cleanup;

+    }

+

+    if (!selected_uri && auth_failed_count == printer_count)

+    {

+      fprintf(stderr, "ERROR:  All failover printers failed with "

+              "authorization issues.\n");

+      rc = CUPS_BACKEND_AUTH_REQUIRED;

+      fprintf(stderr, "ATTR: auth-info-required=%s\n", auth_info_required);

+      goto cleanup;

+    }

+    else if (!selected_uri && retry_count + 1 < retry_max)

+    {

+      fprintf(stderr, "INFO: No suitable printer found...retrying...\n");

+      sleep(2);

+      continue;

+    }

+    else if (selected_uri)

+    {

+      fprintf(stderr, "DEBUG: Using printer, %s.\n", selected_uri);

+      break;

+    }

+  }

+

+  if (!selected_uri)

+  {

+    fprintf(stderr, "ERROR: No suitable printer found.  Aborting print\n");

+    rc = CUPS_BACKEND_FAILED;

+    goto cleanup;

+  }

+

+  rc = move_job(atoi(argv[1]), selected_uri);

+

+  if (job_canceled)

+    rc = CUPS_BACKEND_OK;

+

+cleanup :

+  if (job_canceled)

+    rc = CUPS_BACKEND_OK;

+

+  tmp_device_uri = (char *)cupsArrayFirst(printer_array);

+  do

+  {

+    free((void *)tmp_device_uri);

+  } while ((tmp_device_uri = (char *)cupsArrayNext(printer_array)) != NULL);

+

+  cupsArrayDelete(printer_array);

+  sleep(2);

+  return (rc);

+}

+

+/*

+ * 'check_printer()' - Checks the status of a remote printer and returns

+ *                     back a good/bad/busy status.

+ */

+int

+check_printer(const char *device_uri)

+{

+  ipp_t           *attributes = NULL;     /* attributes for device_uri */

+  ipp_attribute_t *tmp_attribute;         /* for examining attribs     */

+  int              rc = FO_PRINTER_GOOD;  /* return code               */

+  char            *reason;                /* printer state reason */

+  int              i;

+

+  fprintf(stderr, "DEBUG: Checking printer %s\n",device_uri);

+

+  rc = get_printer_attributes(device_uri, &attributes);

+  if ( rc != CUPS_BACKEND_OK )

+  {

+    fprintf(stderr, "DEBUG: Failed to get attributes from printer: %s\n",

+            device_uri);

+    if ( rc == CUPS_BACKEND_AUTH_REQUIRED )

+      return (FO_AUTH_REQUIRED);

+    else

+      return (FO_PRINTER_BAD);

+  }

+

+ /*

+  * Check if printer is accepting jobs

+  */

+  if ((tmp_attribute = ippFindAttribute(attributes,

+                                        "printer-is-accepting-jobs",

+                                        IPP_TAG_BOOLEAN)) != NULL &&

+      !tmp_attribute->values[0].boolean)

+  {

+    fprintf(stderr,

+            "DEBUG: Printer, %s, is not accepting jobs.\n",

+            device_uri);

+

+    rc = FO_PRINTER_BAD;

+  }

+

+ /*

+  * Check if printer is stopped or busy processing

+  */

+  if ((tmp_attribute = ippFindAttribute(attributes,

+                                        "printer-state",

+                                        IPP_TAG_ENUM)) != NULL)

+  {

+    // Printer Stopped

+    if ( tmp_attribute->values[0].integer == IPP_PRINTER_STOPPED )

+    {

+      fprintf(stderr, "DEBUG: Printer, %s, stopped.\n", device_uri);

+      rc = FO_PRINTER_BAD;

+    }

+    // Printer Busy

+    else if ( tmp_attribute->values[0].integer == IPP_PRINTER_PROCESSING )

+    {

+      fprintf(stderr, "DEBUG: Printer %s is busy.\n", device_uri);

+      rc = FO_PRINTER_BUSY;

+    }

+  }

+

+  /*

+   * Parse through the printer-state-reasons

+   */

+  if ((tmp_attribute = ippFindAttribute(attributes, "printer-state-reasons",

+                                        IPP_TAG_KEYWORD)) != NULL)

+  {

+    for (i = 0; i < tmp_attribute->num_values; i++)

+    {

+      reason = tmp_attribute->values[i].string.text;

+      int len = strlen(reason);

+

+      if (len > 8 && !strcmp(reason + len - 8, "-warning"))

+      {

+        fprintf(stderr, "DEBUG: Printer Supply Warning, %s\n", reason);

+        rc = FO_PRINTER_BAD;

+      }

+      else if (len > 6 && !strcmp(reason + len - 6, "-error"))

+      {

+        fprintf(stderr, "DEBUG: Printer Supply Error, %s\n", reason);

+        rc = FO_PRINTER_BAD;

+      }

+    }

+  }

+

+  return (rc);

+}

+

+/*

+ * 'read_config()' - Parses the failover and failover-retries options

+ *

+ */

+static int

+read_config(cups_array_t *printer_array, int *retries, const char *options)

+{

+

+  const char    *tmp;                   /* temporary ptr                     */

+  char          *tok_tmp;               /* temporary ptr for option  parsing */

+  int            jobopts_count = 0;     /* number of options                 */

+  cups_option_t *jobopts = NULL;        /* job options                       */

+

+

+  fprintf(stderr, "DEBUG: Reading Configuration.\n");

+  jobopts_count = cupsParseOptions(options, 0, &jobopts);

+

+  if (!jobopts_count)

+  {

+    fprintf(stderr,

+            "ERROR: No job options!  Cannot find failover options!\n");

+    return (CUPS_BACKEND_STOP);

+  }

+

+ /*

+  * Get attributes from the primary printer

+  */

+  fprintf(stderr, "DEBUG: Searching for failover option.\n");

+

+  if ((tmp = cupsGetOption("failover", jobopts_count, jobopts)) != NULL)

+  {

+    fprintf(stderr, "DEBUG: Failover option contents: %s.\n", tmp);

+

+    tok_tmp = strdup(tmp);

+

+    tmp = strtok(tok_tmp, ",");

+    do

+    {

+      cupsArrayAdd(printer_array, strdup(tmp));

+    } while ((tmp = strtok(NULL,",")) != NULL);

+

+    free(tok_tmp);

+  }

+  else

+  {

+   /*

+    * The queue is misconfigured, so return back CUPS_BACKEND_STOP

+    */

+    fprintf(stderr, "ERROR: failover option not specified!\n");

+    return (CUPS_BACKEND_STOP);

+  }

+

+ /*

+  * Get the failover-retries value, if it exists.

+  */

+  fprintf(stderr, "DEBUG: Searching for failover-retries option.\n");

+

+  if ((tmp = cupsGetOption("failover-retries",

+                           jobopts_count, jobopts)) != NULL)

+  {

+    fprintf(stderr, "DEBUG: failover-retries option contents: %s.\n", tmp);

+    *retries = atoi(tmp);

+  }

+  else

+  {

+    *retries = FAILOVER_DEFAULT_RETRIES;

+    fprintf(stderr, "DEBUG: Failed to get failover-retries option\n");

+    fprintf(stderr, "DEBUG: Defaulted to %d retries\n", *retries);

+  }

+

+  return (CUPS_BACKEND_OK);

+}

+

+/*

+ * 'get_printer_attributes()' - Sends an IPP Get-Attributes request to

+ *                              a URI

+ */

+int

+get_printer_attributes(const char *device_uri, ipp_t **attributes)

+{

+  char               uri[HTTP_MAX_URI];         /* Updated URI without login */

+  int                version;                   /* IPP version */

+  char               scheme[256];               /* Scheme in URI */

+  ipp_status_t       ipp_status;                /* Status of IPP request */

+  char               hostname[1024];            /* Hostname */

+  char               resource[1024];            /* Resource infoo */

+  char               addrname[256];             /* Address name */

+  int                port;                      /* IPP Port number */

+  char               portname[255];             /* Port as string */

+  http_t            *http;                      /* HTTP connection */

+  ipp_t             *request;                   /* IPP request */

+  int                rc = CUPS_BACKEND_OK;      /* Return Code */

+  char               username[256];             /* Username for device URI */

+  char              *option_ptr;                /* for parsing resource opts */

+  const char * const pattrs[] =                 /* Printer attributes wanted */

+    {

+      "printer-is-accepting-jobs",

+      "printer-state",

+      "printer-state-reasons"

+    };

+

+  if (job_canceled)

+    return (CUPS_BACKEND_OK);

+

+  fprintf(stderr, "DEBUG: Getting Printer Attributes.\n");

+  fprintf(stderr, "DEBUG: Device URL %s.\n", device_uri);

+

+ /*

+  * Parse device_uri

+  */

+  if (httpSeparateURI(HTTP_URI_CODING_ALL, device_uri, scheme, sizeof(scheme),

+                     username, sizeof(username), hostname, sizeof(hostname),

+                     &port, resource, sizeof(resource)) != HTTP_URI_OK)

+  {

+    fprintf(stderr, "ERROR: Problem parsing device_uri, %s\n", device_uri);

+    return (CUPS_BACKEND_STOP);

+  }

+

+  if (!port)

+    port = IPP_PORT;

+

+  sprintf(portname, "%d", port);

+

+  fprintf(stderr, "DEBUG: Getting Printer Attributes.\n");

+

+ /*

+  * Configure password

+  */

+  cupsSetPasswordCB(password_cb);

+

+ /*

+  * reset, in case a previous attempt for

+  * another printer left residue

+  */

+  cupsSetUser(NULL);

+  password = NULL;

+  password_retries = 0;

+

+  if (*username)

+  {

+    if ((password = strchr(username, ':')) != NULL)

+    {

+      *password = '\0';

+      password++;

+    }

+

+    cupsSetUser(username);

+  }

+  else if (!getuid())

+  {

+    const char *username_env;

+

+    if ((username_env = getenv("AUTH_USERNAME")) != NULL)

+    {

+      cupsSetUser(username_env);

+      password = getenv("AUTH_PASSWORD");

+    }

+  }

+

+ /*

+  * Try connecting to the remote server...

+  */

+  fprintf(stderr, "DEBUG: Connecting to %s:%d\n", hostname, port);

+  _cupsLangPuts(stderr, _("INFO: Connecting to printer...\n"));

+

+  http = httpConnectEncrypt(hostname, port, cupsEncryption());

+

+ /*

+  * Deal the socket not being open.

+  */

+  if (!http)

+  {

+    int error = errno;          /* Connection error */

+

+    switch (error)

+    {

+    case EHOSTDOWN :

+      _cupsLangPuts(stderr, _("WARNING: "

+                              "The printer may not exist or "

+                              "is unavailable at this time.\n"));

+      break;

+    case EHOSTUNREACH :

+      _cupsLangPuts(stderr, _("WARNING: "

+                              "The printer is unreachable at this "

+                              "time.\n"));

+      break;

+    case ECONNREFUSED :

+      _cupsLangPuts(stderr, _("WARNING: "

+                              "Connection Refused.\n"));

+      break;

+    default :

+      fprintf(stderr, "DEBUG: Connection error: %s\n", strerror(errno));

+      break;

+    }

+

+    rc = CUPS_BACKEND_FAILED;

+    sleep(5);

+    goto prt_available_cleanup;

+  }

+

+

+#ifdef AF_INET6

+  if (http->hostaddr->addr.sa_family == AF_INET6)

+    fprintf(stderr, "DEBUG: Connected to [%s]:%d (IPv6)...\n",

+            httpAddrString(http->hostaddr, addrname, sizeof(addrname)),

+            ntohs(http->hostaddr->ipv6.sin6_port));

+  else

+#endif /* AF_INET6 */

+  if (http->hostaddr->addr.sa_family == AF_INET)

+    fprintf(stderr, "DEBUG: Connected to %s:%d (IPv4)...\n",

+            httpAddrString(http->hostaddr, addrname, sizeof(addrname)),

+            ntohs(http->hostaddr->ipv4.sin_port));

+

+ /*

+  * Search the resource string for options.

+  * We only care about version, for the moment.

+  */

+  version = 11;

+

+  if ((option_ptr = strchr(resource, '?')) != NULL)

+  {

+    *option_ptr++ = '\0';

+

+    if ((option_ptr = strstr(option_ptr, "version="))!=NULL)

+    {

+      int   minor;       /* minor version from URI */

+      int   major;       /* major version from URI */

+      char *version_str; /* ipp version */

+

+      option_ptr += 8;

+      version_str = option_ptr;

+

+      while (*option_ptr && *option_ptr != '&' && *option_ptr != '+')

+        option_ptr++;

+

+      if (*option_ptr)

+        *option_ptr = '\0';

+

+      sscanf(version_str, "%d.%d", &major, &minor);

+

+      version = (major * 10) + minor;

+

+      switch(version)

+      {

+      case 10 :

+      case 11 :

+      case 20 :

+      case 21 :

+        fprintf(stderr,

+                "DEBUG: Set version to %d from URI\n",

+                version);

+        break;

+      default :

+        _cupsLangPrintf(stderr,

+                        _("DEBUG: Invalid version, %d, from URI.  "

+                          "Using default of 1.1 \n"),

+                        version);

+        version = 11;

+      }

+    }

+  }

+

+

+ /*

+  * Build a URI for the printer.  We can't use the URI in argv[0]

+  * because it might contain username:password information...

+  */

+  if (httpAssembleURI(HTTP_URI_CODING_ALL, uri, sizeof(uri), scheme, NULL,

+                      hostname, port, resource) != HTTP_URI_OK)

+  {

+    fprintf(stderr, "ERROR: Problem assembling printer URI from host %s, "

+            "port %d, resource %s\n", hostname, port, resource);