Merge branch 'feature/upstream' into develop

1 files changed, 2645 insertions, 0 deletions

diff --git a/backend/pixma/pixma_bjnp.c b/backend/pixma/pixma_bjnp.c
new file mode 100644
index 0000000..34ba918
--- /dev/null
+++ b/backend/pixma/pixma_bjnp.c
@@ -0,0 +1,2645 @@
+/* SANE - Scanner Access Now Easy.
+
+   Copyright (C) 2008  2012 by Louis Lagendijk
+
+   This file is part of the SANE package.
+
+   SANE is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   SANE is distributed in the hope that it will be useful, but WITHOUT
+   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+   or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
+   License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with sane; see the file COPYING.  If not, write to the Free
+   Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+   As a special exception, the authors of SANE give permission for
+   additional uses of the libraries contained in this release of SANE.
+
+   The exception is that, if you link a SANE library with other files
+   to produce an executable, this does not by itself cause the
+   resulting executable to be covered by the GNU General Public
+   License.  Your use of that executable is in no way restricted on
+   account of linking the SANE library code into it.
+
+   This exception does not, however, invalidate any other reasons why
+   the executable file might be covered by the GNU General Public
+   License.
+
+   If you submit changes to SANE to the maintainers to be included in
+   a subsequent release, you agree by submitting the changes that
+   those changes may be distributed with this exception intact.
+
+   If you write modifications of your own for SANE, it is your choice
+   whether to permit this exception to apply to your modifications.
+   If you do not wish that, delete this exception notice.
+*/
+
+#undef BACKEND_NAME
+#define BACKEND_NAME bjnp
+
+#include  "../include/sane/config.h"
+#include  "../include/sane/sane.h"
+
+/*
+ * Standard types etc
+ */
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
+#include <unistd.h>
+#include <stdio.h>
+#ifdef HAVE_STDINT_H
+#include <stdint.h>
+#endif
+#ifdef HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+#ifdef HAVE_SYS_TIME_H
+#include <sys/time.h>
+#endif
+#ifdef HAVE_LIMITS_H
+#include <limits.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+/*
+ * networking stuff
+ */
+#ifdef HAVE_SYS_SOCKET_H
+#include <sys/socket.h>
+#endif
+#ifdef HAVE_NETINET_IN_H
+#include <netinet/in.h>
+#endif
+#include <netinet/tcp.h>
+#include <arpa/inet.h>
+#include <netdb.h>
+#include <net/if.h>
+#ifdef HAVE_IFADDRS_H
+#include <ifaddrs.h>
+#endif
+#ifdef HAVE_SYS_SELECT_H
+#include <sys/select.h>
+#endif
+#ifdef HAVE_PWD_H
+#include <pwd.h>
+#endif
+#include <errno.h>
+#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
+
+#include "pixma_bjnp_private.h"
+#include "pixma_bjnp.h"
+/* #include "pixma_rename.h" */
+#include "pixma.h"
+#include "pixma_common.h"
+
+#ifndef SSIZE_MAX
+# define SSIZE_MAX      LONG_MAX
+#endif
+
+/* static data */
+static bjnp_device_t device[BJNP_NO_DEVICES];
+static int bjnp_no_devices = 0;
+
+/*
+ * Private functions
+ */
+
+static const struct pixma_config_t *lookup_scanner(const char *makemodel,
+                                                   const struct pixma_config_t *const pixma_devices[])
+{
+  int i;
+  const struct pixma_config_t *cfg;
+  char *match;
+
+  for (i = 0; pixma_devices[i]; i++)
+    {
+      /* loop through the device classes (mp150, mp730 etc) */
+      for (cfg = pixma_devices[i]; cfg->name; cfg++)
+        {
+          /* loop through devices in class */
+          PDBG( bjnp_dbg( LOG_DEBUG3, "lookup_scanner: Checking for %s in %s\n", makemodel, cfg->model));
+          if ((match = strcasestr (makemodel, cfg->model)) != NULL)
+            {
+              /* possible match found, make sure it is not a partial match */
+              /* MP600 and MP600R are different models! */
+              /* some models contain ranges, so check for a '-' too */
+
+              if ((match[strlen(cfg->model)] == ' ') ||
+                  (match[strlen(cfg->model)] == '\0') ||
+                  (match[strlen(cfg->model)] == '-'))
+                {
+                  PDBG( bjnp_dbg (LOG_DEBUG, "lookup_scanner: Scanner model found: Name %s(%s) matches %s\n", cfg->model, cfg->name, makemodel));
+                  return cfg;
+                }
+            }
+       }
+    }
+  PDBG( bjnp_dbg (LOG_DEBUG, "lookup_scanner: Scanner model %s not found, giving up!\n", makemodel));
+  return NULL;
+}
+
+static void
+u8tohex (char *string, const uint8_t *value, int len )
+{
+  int i;
+  int x;
+  const char hdigit[16] =
+    { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd',
+    'e', 'f'
+  };
+  for (i = 0; i < len; i++)
+    {
+      x = value[i];
+      string[ 2 * i ] = hdigit[(x >> 4) & 0xf];
+      string[ 2 * i + 1] = hdigit[x & 0xf];
+    }
+  string[2 * len ] = '\0';
+}
+
+static void
+u32tohex (uint32_t x, char *str)
+{
+  uint8_t uint8[4];
+  uint8[0] = (uint8_t)(x >> 24);
+  uint8[1] = (uint8_t)(x >> 16);
+  uint8[2] = (uint8_t)(x >> 8);
+  uint8[3] = (uint8_t)x ;
+  u8tohex(str, uint8, 4);
+}
+
+static void
+bjnp_hexdump (int level, const void *d_, unsigned len)
+{
+  const uint8_t *d = (const uint8_t *) (d_);
+  unsigned ofs, c, plen;
+  char line[100];               /* actually only 1+8+1+8*3+1+8*3+1 = 61 bytes needed */
+
+  if (level > DBG_LEVEL)
+    return;
+  if (level == DBG_LEVEL)
+    /* if debuglevel == exact match and buffer contains more than 3 lines, print 2 lines + .... */
+    plen = (len > 64) ? 32: len;
+  else
+    plen = len;
+  ofs = 0;
+  while (ofs < plen)
+    {
+      char *p;
+      line[0] = ' ';
+      u32tohex (ofs, line + 1);
+      line[9] = ':';
+      p = line + 10;
+      for (c = 0; c != 16 && (ofs + c) < plen; c++)
+        {
+          u8tohex (p, d + ofs + c, 1);
+          p[2] = ' ';
+          p += 3;
+          if (c == 7)
+            {
+              p[0] = ' ';
+              p++;
+            }
+        }
+      p[0] = '\0';
+      bjnp_dbg (level, "%s\n", line);
+      ofs += c;
+    }
+  if (len > plen)
+    bjnp_dbg(level, "......\n");
+}
+
+static int sa_is_equal( const bjnp_sockaddr_t * sa1, const bjnp_sockaddr_t * sa2)
+{
+  if ((sa1 == NULL) || (sa2 == NULL) )
+    return 0;
+
+  if (sa1->addr.sa_family == sa2-> addr.sa_family)
+    {
+      if( sa1 -> addr.sa_family == AF_INET)
+        {
+          if ( (sa1->ipv4.sin_port == sa2->ipv4.sin_port) &&
+               (sa1->ipv4.sin_addr.s_addr == sa2->ipv4.sin_addr.s_addr))
+            {
+            return 1;
+            }
+        }
+#ifdef ENABLE_IPV6
+      else if (sa1 -> addr.sa_family == AF_INET6 )
+        {
+          if ( (sa1-> ipv6.sin6_port == sa2->ipv6.sin6_port) &&
+              (memcmp(&(sa1->ipv6.sin6_addr), &(sa2->ipv6.sin6_addr), sizeof(struct in6_addr)) == 0))
+            {
+              return 1;
+            }
+        }
+#endif
+    }
+    return 0;
+}
+
+static int
+sa_size( const bjnp_sockaddr_t *sa)
+{
+  switch (sa -> addr.sa_family)
+    {
+      case AF_INET:
+        return (sizeof(struct sockaddr_in) );
+#ifdef ENABLE_IPV6
+      case AF_INET6:
+        return (sizeof(struct sockaddr_in6) );
+#endif
+      default:
+        /* should not occur */
+        return sizeof( bjnp_sockaddr_t );
+    }
+}
+
+static int
+get_protocol_family( const bjnp_sockaddr_t *sa)
+{
+  switch (sa -> addr.sa_family)
+    {
+      case AF_INET:
+        return PF_INET;
+        break;
+#ifdef ENABLE_IPV6
+      case AF_INET6:
+        return PF_INET6;
+        break;
+#endif
+      default:
+        /* should not occur */
+        return -1;
+    }
+}
+
+static void
+get_address_info ( const bjnp_sockaddr_t *addr, char * addr_string, int *port)
+{
+  char tmp_addr[BJNP_HOST_MAX];
+  if ( addr->addr.sa_family == AF_INET)
+    {
+      inet_ntop( AF_INET, &(addr -> ipv4.sin_addr.s_addr), addr_string, BJNP_HOST_MAX);
+      *port = ntohs (addr->ipv4.sin_port);
+    }
+#ifdef ENABLE_IPV6
+  else if (addr->addr.sa_family == AF_INET6)
+    {
+      inet_ntop( AF_INET6, addr -> ipv6.sin6_addr.s6_addr, tmp_addr, sizeof(tmp_addr) );
+
+      if (IN6_IS_ADDR_LINKLOCAL( &(addr -> ipv6.sin6_addr) ) )
+          sprintf(addr_string, "[%s%%%d]", tmp_addr, addr -> ipv6.sin6_scope_id);
+
+      *port = ntohs (addr->ipv6.sin6_port);
+    }
+#endif
+  else
+    {
+      /* unknown address family, should not occur */
+      strcpy(addr_string, "Unknown address family");
+      *port = 0;
+    }
+}
+
+static int
+parse_IEEE1284_to_model (char *scanner_id, char *model)
+{
+/*
+ * parses the  IEEE1284  ID of the scanner to retrieve make and model
+ * of the scanner
+ * Returns: 0 = not found
+ *          1 = found, model is set
+ */
+
+  char s[BJNP_IEEE1284_MAX];
+  char *tok;
+  char * model_str;
+
+  strncpy (s, scanner_id, BJNP_IEEE1284_MAX);
+  s[BJNP_IEEE1284_MAX - 1] = '\0';
+  model[0] = '\0';
+
+  tok = strtok (s, ";");
+  while (tok != NULL)
+    {
+      /* MDL contains make and model */
+
+      if (strncmp (tok, "MDL:", strlen("MDL:")) == 0)
+	{
+	  model_str = tok + strlen("MDL:");
+	  strncpy (model, model_str, BJNP_MODEL_MAX);
+	  model[BJNP_MODEL_MAX -1] = '\0';
+	  return 1;
+	}
+      tok = strtok (NULL, ";");
+    }
+  return 0;
+}
+
+static int
+charTo2byte (char *d, const char *s, int len)
+{
+  /*
+   * copy ASCII string to UTF-16 unicode string
+   * len is length of destination buffer
+   * Returns: number of characters copied
+   */
+
+  int done = 0;
+  int copied = 0;
+  int i;
+
+  len = len / 2;
+  for (i = 0; i < len; i++)
+    {
+      d[2 * i] = '\0';
+      if (s[i] == '\0')
+	{
+	  done = 1;
+	}
+      if (done == 0)
+	{
+	  d[2 * i + 1] = s[i];
+	  copied++;
+	}
+      else
+	d[2 * i + 1] = '\0';
+    }
+  return copied;
+}
+
+static bjnp_protocol_defs_t *get_protocol_by_method( char *method)
+{
+  int i = 0;
+  while ( bjnp_protocol_defs[i].method_string != NULL)
+    {
+      if (strcmp(method, bjnp_protocol_defs[i].method_string) == 0)
+        {
+          return &bjnp_protocol_defs[i];
+        }
+      i++;
+    }
+  return NULL;
+}
+
+static bjnp_protocol_defs_t *get_protocol_by_proto_string( char *proto_string)
+{
+  int i = 0;
+  while ( bjnp_protocol_defs[i].proto_string != NULL)
+    {
+      if (strncmp(proto_string, bjnp_protocol_defs[i].proto_string, 4) == 0)
+        {
+          return &bjnp_protocol_defs[i];
+        }
+      i++;
+    }
+  return NULL;
+}
+
+static char *
+getusername (void)
+{
+  static char noname[] = "sane_pixma";
+  struct passwd *pwdent;
+
+#ifdef HAVE_PWD_H
+  if (((pwdent = getpwuid (geteuid ())) != NULL) && (pwdent->pw_name != NULL))
+    return pwdent->pw_name;
+#endif
+  return noname;
+}
+
+
+static char *
+determine_scanner_serial (const char *hostname, const char * mac_address, char *serial)
+{
+  char *dot;
+  char copy[BJNP_HOST_MAX];
+
+  /* determine a "serial number" for the scanner */
+  /* if available we use the hostname or ipv4 address of the printer */
+  /* if we only have a literal ipv6 address, we use the mac-address */
+
+  strcpy(copy, hostname);
+  if (strlen (copy) >= SERIAL_MAX)
+    {
+      /* make the string fit into the serial */
+      /* if this is a FQDN, not an ip-address, remove domain part of the name */
+      if ((dot = strchr (copy, '.')) != NULL)
+        {
+          *dot = '\0';
+        }
+    }
+  /* check if name is still to long. If so use the mac-address */
+  if (strlen(copy) >= SERIAL_MAX)
+    {
+      strcpy(copy, mac_address);
+    }
+  strcpy( serial, copy );
+  return serial;
+}
+
+static int
+bjnp_open_tcp (int devno)
+{
+  int sock;
+  int val;
+  bjnp_sockaddr_t *addr = device[devno].addr;
+  char host[BJNP_HOST_MAX];
+  int port;
+  int connect_timeout = BJNP_TIMEOUT_TCP_CONNECT;
+
+  get_address_info( addr, host, &port);
+  PDBG (bjnp_dbg (LOG_DEBUG, "bjnp_open_tcp: Setting up a TCP socket, dest: %s  port %d\n",
+		   host, port ) );
+
+  if ((sock = socket (get_protocol_family( addr ) , SOCK_STREAM, 0)) < 0)
+    {
+      PDBG (bjnp_dbg (LOG_CRIT, "bjnp_open_tcp: ERROR - Can not create socket: %s\n",
+		       strerror (errno)));
+      return -1;
+    }
+
+  val = 1;
+  setsockopt (sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof (val));
+
+#if 0
+  val = 1;
+  setsockopt (sock, SOL_SOCKET, SO_REUSEPORT, &val, sizeof (val));
+
+  val = 1;
+#endif
+
+  /*
+   * Using TCP_NODELAY improves responsiveness, especially on systems
+   * with a slow loopback interface...
+   */
+
+  val = 1;
+  setsockopt (sock, IPPROTO_TCP, TCP_NODELAY, &val, sizeof (val));
+
+/*
+ * Close this socket when starting another process...
+ */
+
+  fcntl (sock, F_SETFD, FD_CLOEXEC);
+
+  while (connect_timeout > 0)
+    {
+      if (connect
+          (sock, &(addr->addr), sa_size(device[devno].addr)) == 0)
+	    {
+              device[devno].tcp_socket = sock;
+              return 0;
+	    }
+      PDBG (bjnp_dbg( LOG_INFO, "bjnp_open_tcp: INFO - Can not yet connect over TCP to scanner: %s, retrying\n",
+                      strerror(errno)));
+      usleep(BJNP_TCP_CONNECT_INTERVAL * BJNP_USLEEP_MS);
+      connect_timeout = connect_timeout - BJNP_TCP_CONNECT_INTERVAL;
+    }
+  PDBG (bjnp_dbg
+        (LOG_CRIT, "bjnp_open_tcp: ERROR - Can not connect to scanner, giving up!"));
+  return -1;
+}
+
+static int
+split_uri (const char *devname, char *method, char *host, char *port,
+	   char *args)
+{
+  char copy[1024];
+  char *start;
+  char next;
+  int i;
+
+  strncpy (copy, devname, 1024);
+  copy[1023] = '\0';
+  start = copy;
+
+/*
+ * retrieve method
+ */
+  i = 0;
+  while ((start[i] != '\0') && (start[i] != ':'))
+    {
+      i++;
+    }
+
+  if (((strncmp (start + i, "://", 3) != 0)) || (i > BJNP_METHOD_MAX -1 ))
+    {
+      PDBG (bjnp_dbg (LOG_NOTICE, "split_uri: ERROR - Can not find method in %s (offset %d)\n",
+		       devname, i));
+      return -1;
+    }
+
+  start[i] = '\0';
+  strcpy (method, start);
+  start = start + i + 3;
+
+/*
+ * retrieve host
+ */
+
+  if (start[0] == '[')
+    {
+      /* literal IPv6 address */
+
+      char *end_of_address = strchr(start, ']');
+
+      if ( ( end_of_address == NULL) ||
+           ( (end_of_address[1] != ':') && (end_of_address[1] != '/' ) &&  (end_of_address[1] != '\0' )) ||
+           ( (end_of_address - start) >= BJNP_HOST_MAX ) )
+        {
+          PDBG (bjnp_dbg (LOG_NOTICE, "split_uri: ERROR - Can not find hostname or address in %s\n", devname));
+          return -1;
+        }
+      next = end_of_address[1];
+      *end_of_address = '\0';
+      strcpy(host, start + 1);
+      start = end_of_address + 2;
+    }
+  else
+    {
+      i = 0;
+      while ((start[i] != '\0') && (start[i] != '/') && (start[i] != ':'))
+        {
+          i++;
+        }
+      next = start[i];
+      start[i] = '\0';
+      if ((i == 0) || (i >= BJNP_HOST_MAX ) )
+        {
+          PDBG (bjnp_dbg (LOG_NOTICE, "split_uri: ERROR - Can not find hostname or address in %s\n", devname));
+          return -1;
+        }
+      strcpy (host, start);
+      start = start + i +1;
+    }
+
+
+/*
+ * retrieve port number
+ */
+
+  if (next != ':')
+    strcpy(port, "");
+  else
+    {
+      char *end_of_port = strchr(start, '/');
+      if (end_of_port == NULL)
+        {
+          next = '\0';
+        }
+      else
+        {
+          next = *end_of_port;
+          *end_of_port = '\0';
+        }
+      if ((strlen(start) == 0) || (strlen(start) >= BJNP_PORT_MAX ) )
+        {
+          PDBG (bjnp_dbg (LOG_NOTICE, "split_uri: ERROR - Can not find port in %s (have \"%s\")\n", devname, start));
+          return -1;
+        }
+      strcpy(port, start);
+      start = end_of_port + 1;
+    }
+
+/*
+ * Retrieve arguments
+ */
+
+  if (next == '/')
+    {
+    i = strlen(start);
+    if ( i >= BJNP_ARGS_MAX)
+      {
+        PDBG (bjnp_dbg (LOG_NOTICE, "split_uri: ERROR - Argument string too long in %s\n", devname));
+      }
+    strcpy (args, start);
+    }
+  else
+    strcpy (args, "");
+  return 0;
+}
+
+
+
+static void
+set_cmd_from_string (char* protocol_string, struct BJNP_command *cmd, char cmd_code, int payload_len)
+{
+  /*
+   * Set command buffer with command code, session_id and length of payload
+   * Returns: sequence number of command
+   */
+
+  memcpy (cmd->BJNP_id, protocol_string, sizeof (cmd->BJNP_id));
+  cmd->dev_type = BJNP_CMD_SCAN;
+  cmd->cmd_code = cmd_code;
+  cmd->unknown1 = htons (0);
+
+  /* device not yet opened, use 0 for serial and session) */
+  cmd->seq_no = htons (0);
+  cmd->session_id = htons (0);
+  cmd->payload_len = htonl (payload_len);
+}
+
+static void
+set_cmd_for_dev (int devno, struct BJNP_command *cmd, char cmd_code, int payload_len)
+{
+  /*
+   * Set command buffer with command code, session_id and length of payload
+   * Returns: sequence number of command
+   */
+
+  memcpy(cmd->BJNP_id, device[devno].protocol_string, sizeof (cmd->BJNP_id));
+  cmd->dev_type = BJNP_CMD_SCAN;
+  cmd->cmd_code = cmd_code;
+  cmd->unknown1 = htons (0);
+  cmd->seq_no = htons (++(device[devno].serial));
+  cmd->session_id = (cmd_code == CMD_UDP_POLL ) ? 0 : htons (device[devno].session_id);
+  device[devno].last_cmd = cmd_code;
+  cmd->payload_len = htonl (payload_len);
+}
+
+static int
+bjnp_setup_udp_socket ( const int dev_no )
+{
+  /*
+   * Setup a udp socket for the given device
+   * Returns the socket or -1 in case of error
+   */
+
+  int sockfd;
+  char addr_string[256];
+  int port;
+  bjnp_sockaddr_t * addr = device[dev_no].addr;
+
+  get_address_info( addr, addr_string, &port);
+
+  PDBG (bjnp_dbg (LOG_DEBUG, "setup_udp_socket: Setting up a UDP socket, dest: %s  port %d\n",
+		   addr_string, port ) );
+
+  if ((sockfd = socket (get_protocol_family( addr ), SOCK_DGRAM, IPPROTO_UDP)) == -1)
+    {
+      PDBG (bjnp_dbg
+	    (LOG_CRIT, "setup_udp_socket: ERROR - can not open socket - %s\n",
+	     strerror (errno)));
+      return -1;
+    }
+
+  if (connect
+      (sockfd, &(device[dev_no].addr->addr), sa_size(device[dev_no].addr) )!= 0)
+    {
+      PDBG (bjnp_dbg
+	    (LOG_CRIT, "setup_udp_socket: ERROR - connect failed- %s\n",
+	     strerror (errno)));
+      close(sockfd);
+      return -1;
+    }
+  return sockfd;
+}
+
+static int
+udp_command (const int dev_no, char *command, int cmd_len, char *response,
+	     int resp_len)
+{
+  /*
+   * send udp command to given device and recieve the response`
+   * returns: the legth of the response or -1
+   */
+  int sockfd;
+  struct timeval timeout;
+  int result;
+  int try, attempt;
+  int numbytes;
+  fd_set fdset;
+  struct BJNP_command *resp = (struct BJNP_command *) response;
+  struct BJNP_command *cmd = (struct BJNP_command *) command;
+
+  if ( (sockfd = bjnp_setup_udp_socket(dev_no) ) == -1 )
+    {
+      PDBG (bjnp_dbg( LOG_CRIT, "udp_command: ERROR - Can not setup socket\n") );
+      return -1;
+    }
+
+  for (try = 0; try < BJNP_UDP_RETRY_MAX; try++)
+    {
+      if ((numbytes = send (sockfd, command, cmd_len, 0)) != cmd_len)
+	{
+	  PDBG (bjnp_dbg
+		(LOG_NOTICE, "udp_command: ERROR - Sent %d bytes, expected %d\n",
+		 numbytes, cmd_len));
+	  continue;
+	}
+
+      attempt = 0;
+
+      /* wait for data to be received, ignore signals being received */
+      /* skip late udp responses (they have an incorrect sequence number */
+      do
+	{
+	  FD_ZERO (&fdset);
+	  FD_SET (sockfd, &fdset);
+
+	  timeout.tv_sec = device[dev_no].bjnp_ip_timeout /1000;
+	  timeout.tv_usec = device[dev_no].bjnp_ip_timeout %1000;
+	}
+      while (((result =
+	       select (sockfd + 1, &fdset, NULL, NULL, &timeout)) <= 0)
+	     && (errno == EINTR) && (attempt++ < BJNP_MAX_SELECT_ATTEMPTS)
+             && resp-> seq_no != cmd->seq_no);
+
+      if (result <= 0)
+	{
+	  PDBG (bjnp_dbg
+		(LOG_NOTICE, "udp_command: ERROR - select failed: %s\n",
+		 result == 0 ? "timed out" : strerror (errno)));
+	  continue;
+	}
+
+      if ((numbytes = recv (sockfd, response, resp_len, 0)) == -1)
+	{
+	  PDBG (bjnp_dbg
+		(LOG_NOTICE, "udp_command: ERROR - recv failed: %s",
+		 strerror (errno)));
+	  continue;
+	}
+      close(sockfd);
+      return numbytes;
+    }
+
+  /* no response even after retry */
+
+  close(sockfd);
+  PDBG (bjnp_dbg
+        (LOG_CRIT, "udp_command: ERROR - no data received (timeout = %d)\n", device[dev_no].bjnp_ip_timeout ) );
+  return -1;
+}
+
+static int
+get_scanner_id (const int dev_no, char *model)
+{
+  /*
+   * get scanner identity
+   * Sets model (make and model)
+   * Return 0 on success, -1 in case of errors
+   */
+
+  struct BJNP_command cmd;
+  struct IDENTITY *id;
+  char scanner_id[BJNP_IEEE1284_MAX];
+  int resp_len;
+  char resp_buf[BJNP_RESP_MAX];
+  int id_len;
+
+  /* set defaults */
+
+  strcpy (model, "Unidentified scanner");
+
+  set_cmd_for_dev (dev_no, &cmd, CMD_UDP_GET_ID, 0);
+
+  PDBG (bjnp_dbg (LOG_DEBUG2, "get_scanner_id: Get scanner identity\n"));
+  PDBG (bjnp_hexdump (LOG_DEBUG2, (char *) &cmd,
+		       sizeof (struct BJNP_command)));
+
+  if ( ( resp_len =  udp_command (dev_no, (char *) &cmd, sizeof (struct BJNP_command),
+		 resp_buf, BJNP_RESP_MAX) ) < (int)sizeof(struct BJNP_command) )
+    {
+      PDBG (bjnp_dbg (LOG_DEBUG, "get_scanner_id: ERROR - Failed to retrieve scanner identity:\n"));
+      return -1;
+    }
+  PDBG (bjnp_dbg (LOG_DEBUG2, "get_scanner_id: scanner identity:\n"));
+  PDBG (bjnp_hexdump (LOG_DEBUG2, resp_buf, resp_len));
+
+  id = (struct IDENTITY *) resp_buf;
+
+  if (device[dev_no].protocol == PROTOCOL_BJNP)
+    {
+      id_len = MIN(ntohl( id-> cmd.payload_len ) - sizeof(id-> payload.bjnp.id_len), BJNP_IEEE1284_MAX);
+      strncpy(scanner_id, id->payload.bjnp.id, id_len);
+      scanner_id[id_len] = '\0';
+    }
+  else
+    {
+      id_len = MIN(ntohl( id-> cmd.payload_len ), BJNP_IEEE1284_MAX);
+      strncpy(scanner_id, id->payload.mfnp.id, id_len);
+      scanner_id[id_len] = '\0';
+    }
+  PDBG (bjnp_dbg (LOG_INFO, "get_scanner_id: Scanner identity string = %s - length = %d\n", scanner_id, id_len));
+
+  /* get make&model from IEEE1284 id  */
+
+  if (model != NULL)
+  {
+    parse_IEEE1284_to_model (scanner_id, model);
+    PDBG (bjnp_dbg (LOG_INFO, "get_scanner_id: Scanner model = %s\n", model));
+  }
+  return 0;
+}
+
+static int
+get_scanner_name(const bjnp_sockaddr_t *scanner_sa, char *host)
+{
+  /*
+   * Parse identify command responses to ip-address
+   * and hostname. Return qulity of the address
+   */
+
+  struct addrinfo *results;
+  struct addrinfo *result;
+  char ip_address[BJNP_HOST_MAX];
+  int port;
+  int error;
+  int match = 0;
+  int level;
+  char service[64];
+
+#ifdef ENABLE_IPV6
+  if ( ( scanner_sa -> addr.sa_family == AF_INET6 ) &&
+       ( IN6_IS_ADDR_LINKLOCAL( &(scanner_sa -> ipv6.sin6_addr ) ) ) )
+    level = BJNP_ADDRESS_IS_LINK_LOCAL;
+  else
+#endif
+    level = BJNP_ADDRESS_IS_GLOBAL;
+
+  get_address_info( scanner_sa, ip_address, &port );
+
+  /* do reverse name lookup, if hostname can not be found return ip-address */
+
+  if( (error = getnameinfo( &(scanner_sa -> addr) , sa_size( scanner_sa),
+                  host, BJNP_HOST_MAX , NULL, 0, NI_NAMEREQD) ) != 0 )
+    {
+      PDBG (bjnp_dbg(LOG_INFO, "get_scanner_name: Name for %s not found : %s\n",
+                      ip_address, gai_strerror(error) ) );
+      strcpy(host, ip_address);
+      return level;
+    }
+  else
+    {
+      sprintf(service, "%d", port);
+      /* some buggy routers return rubbish if reverse lookup fails, so
+       * we do a forward lookup on the received name to see if the result matches */
+
+      if (getaddrinfo(host , service, NULL, &results) == 0)
+        {
+          result = results;
+
+          while (result != NULL)
+            {
+               if(sa_is_equal( scanner_sa, (bjnp_sockaddr_t *)result-> ai_addr))
+                 {
+                     /* found match, good */
+                     PDBG (bjnp_dbg (LOG_INFO,
+                              "get_scanner_name: Forward lookup for %s succeeded, using as hostname\n", host));
+                    match = 1;
+                    level = BJNP_ADDRESS_HAS_FQDN;
+                    break;
+                 }
+              result = result-> ai_next;
+            }
+          freeaddrinfo(results);
+
+          if (match != 1)
+            {
+              PDBG (bjnp_dbg (LOG_INFO,
+                 "get_scanner_name: Forward lookup for %s succeeded, IP-address does not match, using IP-address %s instead\n",
+                 host, ip_address));
+              strcpy (host, ip_address);
+            }
+         }
+       else
+         {
+           /* forward lookup failed, use ip-address */
+           PDBG ( bjnp_dbg (LOG_INFO, "get_scanner_name: Forward lookup of %s failed, using IP-address", ip_address));
+           strcpy (host, ip_address);
+         }
+    }
+  return level;
+}
+
+static int
+get_port_from_sa(const bjnp_sockaddr_t scanner_sa)
+{
+#ifdef ENABLE_IPV6
+  if ( scanner_sa.addr.sa_family == AF_INET6 )
+    {
+      return ntohs(scanner_sa.ipv6.sin6_port);
+    }
+  else
+#endif
+  if ( scanner_sa.addr.sa_family == AF_INET )
+    {
+      return ntohs(scanner_sa.ipv4.sin_port);
+    }
+  return -1;
+}
+
+static int create_broadcast_socket( const bjnp_sockaddr_t * local_addr )
+{
+  int sockfd = -1;
+  int broadcast = 1;
+  int ipv6_v6only = 1;
+
+
+ if ((sockfd = socket (local_addr-> addr.sa_family, SOCK_DGRAM, 0)) == -1)
+    {
+      PDBG (bjnp_dbg
+            (LOG_CRIT, "create_broadcast_socket: ERROR - can not open socket - %s",
+             strerror (errno)));
+      return -1;
+    }
+
+  /* Set broadcast flag on socket */
+
+  if (setsockopt
+      (sockfd, SOL_SOCKET, SO_BROADCAST, (const char *) &broadcast,
+       sizeof (broadcast)) != 0)
+    {
+      PDBG (bjnp_dbg
+            (LOG_CRIT,
+             "create_broadcast_socket: ERROR - setting socket option SO_BROADCAST failed - %s",
+             strerror (errno)));
+      close (sockfd);
+      return -1;
+    };
+
+  /* For an IPv6 socket, bind to v6 only so a V6 socket can co-exist with a v4 socket */
+  if ( (local_addr -> addr.sa_family == AF_INET6) && ( setsockopt
+      (sockfd, IPPROTO_IPV6, IPV6_V6ONLY, (const char *) &ipv6_v6only,
+       sizeof (ipv6_v6only)) != 0) )
+    {
+      PDBG (bjnp_dbg
+            (LOG_CRIT,
+             "create_broadcast_socket: ERROR - setting socket option IPV6_V6ONLY failed - %s",
+             strerror (errno)));
+      close (sockfd);
+      return -1;
+    };
+
+  if (bind
+      (sockfd, &(local_addr->addr),
+       (socklen_t) sa_size( local_addr)) != 0)
+    {
+      PDBG (bjnp_dbg
+            (LOG_CRIT,
+             "create_broadcast_socket: ERROR - bind socket to local address failed - %s\n",
+             strerror (errno)));
+      close (sockfd);
+      return -1;
+    }
+  return sockfd;
+}
+
+static int
+prepare_socket(const char *if_name, const bjnp_sockaddr_t *local_sa,
+               const bjnp_sockaddr_t *broadcast_sa, bjnp_sockaddr_t * dest_sa)
+{
+  /*
+   * Prepare a socket for broadcast or multicast
+   * Input:
+   * if_name: the name of the interface
+   * local_sa: local address to use
+   * broadcast_sa: broadcast address to use, if NULL we use all hosts
+   * dest_sa: (write) where to return destination address of broadcast
+   * retuns: open socket or -1
+   */
+
+  int socket = -1;
+  bjnp_sockaddr_t local_sa_copy;
+
+  if ( local_sa == NULL )
+    {
+      PDBG (bjnp_dbg (LOG_DEBUG,
+                       "prepare_socket: %s is not a valid IPv4 interface, skipping...\n",
+                       if_name));
+      return -1;
+    }
+
+  memset( &local_sa_copy, 0, sizeof(local_sa_copy) );
+  memcpy( &local_sa_copy, local_sa, sa_size(local_sa) );
+
+  switch( local_sa_copy.addr.sa_family )
+    {
+      case AF_INET:
+        {
+          local_sa_copy.ipv4.sin_port = htons(BJNP_PORT_SCAN);
+
+          if (local_sa_copy.ipv4.sin_addr.s_addr == htonl (INADDR_LOOPBACK) )
+            {
+              /* not a valid interface */
+
+              PDBG (bjnp_dbg (LOG_DEBUG,
+                               "prepare_socket: %s is not a valid IPv4 interface, skipping...\n",
+	                       if_name));
+              return -1;
+            }
+
+
+          /* send broadcasts to the broadcast address of the interface */
+
+          memcpy(dest_sa, broadcast_sa, sa_size(dest_sa) );
+
+	  /* we fill port when we send the broadcast */
+          dest_sa -> ipv4.sin_port = htons(0);
+
+          if ( (socket = create_broadcast_socket( &local_sa_copy) ) != -1)
+            {
+               PDBG (bjnp_dbg (LOG_INFO, "prepare_socket: %s is IPv4 capable, sending broadcast, socket = %d\n",
+                      if_name, socket));
+            }
+          else
+            {
+              PDBG (bjnp_dbg (LOG_INFO, "prepare_socket: ERROR - %s is IPv4 capable, but failed to create a socket.\n",
+                    if_name));
+              return -1;
+            }
+        }
+        break;
+#ifdef ENABLE_IPV6
+      case AF_INET6:
+        {
+          local_sa_copy.ipv6.sin6_port = htons(BJNP_PORT_SCAN);
+
+          if (IN6_IS_ADDR_LOOPBACK( &(local_sa_copy.ipv6.sin6_addr) ) )
+            {
+              /* not a valid interface */
+
+              PDBG (bjnp_dbg (LOG_DEBUG,
+                               "prepare_socket: %s is not a valid IPv6 interface, skipping...\n",
+	                       if_name));
+              return -1;
+            }
+          else
+            {
+              dest_sa -> ipv6.sin6_family = AF_INET6;
+
+              /* We fill port when we send the broadcast */
+              dest_sa -> ipv6.sin6_port = htons(0);
+
+              inet_pton(AF_INET6, "ff02::1", dest_sa -> ipv6.sin6_addr.s6_addr);
+              if ( (socket = create_broadcast_socket( &local_sa_copy ) ) != -1)
+                {
+                   PDBG (bjnp_dbg (LOG_INFO, "prepare_socket: %s is IPv6 capable, sending broadcast, socket = %d\n",
+                          if_name, socket));
+                }
+              else
+                {
+                  PDBG (bjnp_dbg (LOG_INFO, "prepare_socket: ERROR - %s is IPv6 capable, but failed to create a socket.\n",
+                        if_name));
+                  return -1;
+                }
+            }
+          }
+          break;
+#endif
+
+      default:
+        socket = -1;
+    }
+  return socket;
+}
+
+static int
+bjnp_send_broadcast (int sockfd, const bjnp_sockaddr_t * broadcast_addr, int port,
+                     struct BJNP_command cmd, int size)
+{
+  int num_bytes;
+  bjnp_sockaddr_t dest_addr;
+
+  /* set address to send packet to broadcast address of interface, */
+  /* with port set to the destination port */
+
+  memcpy(&dest_addr,  broadcast_addr, sizeof(dest_addr));
+  if( dest_addr.addr.sa_family == AF_INET)
+    {
+      dest_addr.ipv4.sin_port = htons(port);
+    }
+#ifdef ENABLE_IPV6
+  if( dest_addr.addr.sa_family == AF_INET6)
+    {
+      dest_addr.ipv6.sin6_port = htons(port);
+    }
+#endif
+
+  if ((num_bytes = sendto (sockfd, &cmd, size, 0,
+			  &(dest_addr.addr),
+			  sa_size( broadcast_addr)) ) != size)
+    {
+      PDBG (bjnp_dbg (LOG_INFO,
+		       "bjnp_send_broadcast: Socket: %d: ERROR - sent only %x = %d bytes of packet, error = %s\n",
+		       sockfd, num_bytes, num_bytes, strerror (errno)));
+      /* not allowed, skip this interface */
+
+      return -1;
+    }
+  return sockfd;
+}
+
+static void
+bjnp_finish_job (int devno)
+{
+/*
+ * Signal end of scanjob to scanner
+ */
+
+  char resp_buf[BJNP_RESP_MAX];
+  int resp_len;
+  struct BJNP_command cmd;
+
+  set_cmd_for_dev (devno, &cmd, CMD_UDP_CLOSE, 0);
+
+  PDBG (bjnp_dbg (LOG_DEBUG2, "bjnp_finish_job: Finish scanjob\n"));
+  PDBG (bjnp_hexdump
+	(LOG_DEBUG2, (char *) &cmd, sizeof (struct BJNP_command)));
+  resp_len =
+    udp_command (devno, (char *) &cmd, sizeof (struct BJNP_command), resp_buf,
+		 BJNP_RESP_MAX);
+
+  if (resp_len != sizeof (struct BJNP_command))
+    {
+      PDBG (bjnp_dbg
+	    (LOG_INFO,
+	     "bjnp_finish_job: ERROR - Received %d characters on close scanjob command, expected %d\n",
+	     resp_len, (int) sizeof (struct BJNP_command)));
+      return;
+    }
+  PDBG (bjnp_dbg (LOG_DEBUG2, "bjnp_finish_job: Finish scanjob response\n"));
+  PDBG (bjnp_hexdump (LOG_DEBUG2, resp_buf, resp_len));
+
+}
+
+#ifdef PIXMA_BJNP_USE_STATUS
+static int
+bjnp_poll_scanner (int devno, char type,char *hostname, char *user, SANE_Byte *status, int size)
+{
+/*
+ * send details of user to the scanner
+ */
+
+  char cmd_buf[BJNP_CMD_MAX];
+  char resp_buf[BJNP_RESP_MAX];
+  int resp_len;
+  int len = 0;			/* payload length */
+  int buf_len;			/* length of the whole command  buffer */
+  struct POLL_DETAILS *poll;
+  struct POLL_RESPONSE *response;
+  char user_host[256];
+  time_t t;
+  int user_host_len;
+
+  poll = (struct POLL_DETAILS *) cmd_buf;
+  memset( poll, 0, sizeof( struct POLL_DETAILS));
+  memset( &resp_buf, 0, sizeof( resp_buf) );
+
+
+  /* create payload */
+  poll->type = htons(type);
+
+  user_host_len =  sizeof( poll -> extensions.type2.user_host);
+  snprintf(user_host, (user_host_len /2) ,"%s  %s", user, hostname);
+  user_host[ user_host_len /2 + 1] = '\0';
+
+  switch( type) {
+    case 0:
+      len = 80;
+      break;
+    case 1:
+      charTo2byte(poll->extensions.type1.user_host, user_host, user_host_len);
+      len = 80;
+      break;
+    case 2:
+      poll->extensions.type2.dialog = htonl(device[devno].dialog);
+      charTo2byte(poll->extensions.type2.user_host, user_host, user_host_len);
+      poll->extensions.type2.unknown_1 = htonl(0x14);
+      poll->extensions.type2.unknown_2 = htonl(0x10);
+      t = time (NULL);
+      strftime (poll->extensions.type2.ascii_date,
+                sizeof (poll->extensions.type2.ascii_date),
+               "%Y%m%d%H%M%S", localtime (&t));
+      len = 116;
+      break;
+    case 5:
+      poll->extensions.type5.dialog = htonl(device[devno].dialog);
+      charTo2byte(poll->extensions.type5.user_host, user_host, user_host_len);
+      poll->extensions.type5.unknown_1 = htonl(0x14);
+      poll->extensions.type5.key = htonl(device[devno].status_key);
+      len = 100;
+      break;
+    default:
+      PDBG (bjnp_dbg (LOG_INFO, "bjnp_poll_scanner: unknown packet type: %d\n", type));
+      return -1;
+  };
+  /* we can only now set the header as we now know the length of the payload */
+  set_cmd_for_dev (devno, (struct BJNP_command *) cmd_buf, CMD_UDP_POLL,
+	   len);
+
+  buf_len = len + sizeof(struct BJNP_command);
+  PDBG (bjnp_dbg (LOG_DEBUG2, "bjnp_poll_scanner: Poll details (type %d)\n", type));
+  PDBG (bjnp_hexdump (LOG_DEBUG2, cmd_buf,
+		       buf_len));
+
+  resp_len = udp_command (devno, cmd_buf, buf_len,  resp_buf, BJNP_RESP_MAX);
+
+  if (resp_len > 0)
+    {
+      PDBG (bjnp_dbg (LOG_DEBUG2, "bjnp_poll_scanner: Poll details response:\n"));
+      PDBG (bjnp_hexdump (LOG_DEBUG2, resp_buf, resp_len));
+      response = (struct POLL_RESPONSE *) resp_buf;
+
+      device[devno].dialog = ntohl( response -> dialog );
+
+      if ( response -> result[3] == 1 )
+        {
+          return BJNP_RESTART_POLL;
+        }
+      if ( (response -> result[2] & 0x80) != 0)
+        {
+          memcpy( status, response->status, size);
+          PDBG( bjnp_dbg(LOG_INFO, "bjnp_poll_scanner: received button status!\n"));
+	  PDBG (bjnp_hexdump( LOG_DEBUG2, status, size ));
+	  device[devno].status_key = ntohl( response -> key );
+          return  size;
+        }
+    }
+  return 0;
+}
+#endif
+
+static void
+bjnp_send_job_details (int devno, char *hostname, char *user, char *title)
+{
+/*
+ * send details of scanjob to scanner
+ */
+
+  char cmd_buf[BJNP_CMD_MAX];
+  char resp_buf[BJNP_RESP_MAX];
+  int resp_len;
+  struct JOB_DETAILS *job;
+  struct BJNP_command *resp;
+
+  /* send job details command */
+
+  set_cmd_for_dev (devno, (struct BJNP_command *) cmd_buf, CMD_UDP_JOB_DETAILS,
+	   sizeof (*job) - sizeof (struct BJNP_command));
+
+  /* create payload */
+
+  job = (struct JOB_DETAILS *) (cmd_buf);
+  charTo2byte (job->unknown, "", sizeof (job->unknown));
+  charTo2byte (job->hostname, hostname, sizeof (job->hostname));
+  charTo2byte (job->username, user, sizeof (job->username));
+  charTo2byte (job->jobtitle, title, sizeof (job->jobtitle));
+
+  PDBG (bjnp_dbg (LOG_DEBUG2, "bjnp_send_job_details: Job details\n"));
+  PDBG (bjnp_hexdump (LOG_DEBUG2, cmd_buf,
+		       (sizeof (struct BJNP_command) + sizeof (*job))));
+
+  resp_len = udp_command (devno, cmd_buf,
+			  sizeof (struct JOB_DETAILS), resp_buf,
+			  BJNP_RESP_MAX);
+
+  if (resp_len > 0)
+    {
+      PDBG (bjnp_dbg (LOG_DEBUG2, "bjnp_send_job_details: Job details response:\n"));
+      PDBG (bjnp_hexdump (LOG_DEBUG2, resp_buf, resp_len));
+      resp = (struct BJNP_command *) resp_buf;
+      device[devno].session_id = ntohs (resp->session_id);
+    }
+}
+
+static int
+bjnp_get_scanner_mac_address ( int devno, char *mac_address )
+{
+/*
+ * send discover to scanner
+ */
+
+  char cmd_buf[BJNP_CMD_MAX];
+  char resp_buf[BJNP_RESP_MAX];
+  int resp_len;
+  struct DISCOVER_RESPONSE *resp = (struct DISCOVER_RESPONSE * )&resp_buf;;
+
+  /* send job details command */
+
+  set_cmd_for_dev (devno, (struct BJNP_command *) cmd_buf, CMD_UDP_DISCOVER, 0);
+  resp_len = udp_command (devno, cmd_buf,
+			  sizeof (struct BJNP_command), resp_buf,
+			  BJNP_RESP_MAX);
+
+  if (resp_len > 0)
+    {
+      PDBG (bjnp_dbg (LOG_DEBUG2, "bjnp_get_scanner_mac_address: Discover response:\n"));
+      PDBG (bjnp_hexdump (LOG_DEBUG2, resp_buf, resp_len));
+      u8tohex( mac_address, resp -> mac_addr, sizeof( resp -> mac_addr ) );
+      return 0;
+    }
+  return -1;
+}
+
+static int
+bjnp_write (int devno, const SANE_Byte * buf, size_t count)
+{
+/*
+ * This function writes TCP data to the scanner.
+ * Returns: number of bytes written to the scanner
+ */
+  int sent_bytes;
+  int terrno;
+  struct SCAN_BUF bjnp_buf;
+
+  if (device[devno].scanner_data_left)
+    {
+      PDBG (bjnp_dbg
+	    (LOG_CRIT, "bjnp_write: ERROR - scanner data left = 0x%lx = %ld\n",
+	     (unsigned long) device[devno].scanner_data_left,
+	     (unsigned long) device[devno].scanner_data_left));
+    }
+  /* set BJNP command header */
+
+  set_cmd_for_dev (devno, (struct BJNP_command *) &bjnp_buf, CMD_TCP_SEND, count);
+  memcpy (bjnp_buf.scan_data, buf, count);
+  PDBG (bjnp_dbg (LOG_DEBUG, "bjnp_write: sending 0x%lx = %ld bytes\n",
+		   (unsigned long) count, (unsigned long) count);
+	PDBG (bjnp_hexdump (LOG_DEBUG2, (char *) &bjnp_buf,
+			     sizeof (struct BJNP_command) + count)));
+
+  if ((sent_bytes =
+       send (device[devno].tcp_socket, &bjnp_buf,
+	     sizeof (struct BJNP_command) + count, 0)) <
+      (ssize_t) (sizeof (struct BJNP_command) + count))
+    {
+      /* return result from write */
+      terrno = errno;
+      PDBG (bjnp_dbg (LOG_CRIT, "bjnp_write: ERROR - Could not send data!\n"));
+      errno = terrno;
+      return sent_bytes;
+    }
+  /* correct nr of bytes sent for length of command */
+
+  else if (sent_bytes != (int) (sizeof (struct BJNP_command) + count))
+    {
+      errno = EIO;
+      return -1;
+    }
+  return count;
+}
+
+static int
+bjnp_send_read_request (int devno)
+{
+/*
+ * This function reads responses from the scanner.
+ * Returns: 0 on success, else -1
+ *
+ */
+  int sent_bytes;
+  int terrno;
+  struct BJNP_command bjnp_buf;
+
+  if (device[devno].scanner_data_left)
+    PDBG (bjnp_dbg
+	  (LOG_CRIT,
+	   "bjnp_send_read_request: ERROR - scanner data left = 0x%lx = %ld\n",
+	   (unsigned long) device[devno].scanner_data_left,
+	   (unsigned long) device[devno].scanner_data_left));
+
+  /* set BJNP command header */
+
+  set_cmd_for_dev (devno, (struct BJNP_command *) &bjnp_buf, CMD_TCP_REQ, 0);
+
+  PDBG (bjnp_dbg (LOG_DEBUG, "bjnp_send_read_req sending command\n"));
+  PDBG (bjnp_hexdump (LOG_DEBUG2, (char *) &bjnp_buf,
+		       sizeof (struct BJNP_command)));
+
+  if ((sent_bytes =
+       send (device[devno].tcp_socket, &bjnp_buf, sizeof (struct BJNP_command),
+	     0)) < 0)
+    {
+      /* return result from write */
+      terrno = errno;
+      PDBG (bjnp_dbg
+	    (LOG_CRIT, "bjnp_send_read_request: ERROR - Could not send data!\n"));
+      errno = terrno;
+      return -1;
+    }
+  return 0;
+}
+
+static SANE_Status
+bjnp_recv_header (int devno, size_t *payload_size )
+{
+/*
+ * This function receives the response header to bjnp commands.
+ * devno device number
+ * size: return value for data size returned by scanner
+ * Returns:
+ * SANE_STATUS_IO_ERROR when any IO error occurs
+ * SANE_STATUS_GOOD in case no errors were encountered
+ */
+  struct BJNP_command resp_buf;
+  fd_set input;
+  struct timeval timeout;
+  int recv_bytes;
+  int terrno;
+  int result;
+  int fd;
+  int attempt;
+
+  PDBG (bjnp_dbg
+	(LOG_DEBUG, "bjnp_recv_header: receiving response header\n") );
+  fd = device[devno].tcp_socket;
+
+  *payload_size = 0;
+  attempt = 0;
+  do
+    {
+      /* wait for data to be received, ignore signals being received */
+      FD_ZERO (&input);
+      FD_SET (fd, &input);
+
+      timeout.tv_sec = device[devno].bjnp_ip_timeout /1000;
+      timeout.tv_usec = device[devno].bjnp_ip_timeout %1000;
+    }
+  while ( ( (result = select (fd + 1, &input, NULL, NULL, &timeout)) <= 0) &&
+	 (errno == EINTR) && (attempt++ < BJNP_MAX_SELECT_ATTEMPTS));
+
+  if (result < 0)
+    {
+      terrno = errno;
+      PDBG (bjnp_dbg (LOG_CRIT,
+		       "bjnp_recv_header: ERROR - could not read response header (select): %s!\n",
+		       strerror (terrno)));
+      errno = terrno;
+      return SANE_STATUS_IO_ERROR;
+    }
+  else if (result == 0)
+    {
+      terrno = errno;
+      PDBG (bjnp_dbg (LOG_CRIT,
+		"bjnp_recv_header: ERROR - could not read response header (select timed out after %d ms)!\n",
+		device[devno].bjnp_ip_timeout ) );
+      errno = terrno;
+      return SANE_STATUS_IO_ERROR;
+    }
+
+  /* get response header */
+
+  if ((recv_bytes =
+       recv (fd, (char *) &resp_buf,
+	     sizeof (struct BJNP_command),
+	     0)) != sizeof (struct BJNP_command))
+    {
+      terrno = errno;
+      if (recv_bytes == 0)
+        {
+          PDBG (bjnp_dbg (LOG_CRIT,
+          		"bjnp_recv_header: ERROR - (recv) Scanner closed the TCP-connection!\n"));
+        } else {
+          PDBG (bjnp_dbg (LOG_CRIT,
+	      	       "bjnp_recv_header: ERROR - (recv) could not read response header, received %d bytes!\n",
+		       recv_bytes));
+          PDBG (bjnp_dbg
+	  		(LOG_CRIT, "bjnp_recv_header: ERROR - (recv) error: %s!\n",
+	     		strerror (terrno)));
+        }
+      errno = terrno;
+      return SANE_STATUS_IO_ERROR;
+    }
+
+  if (resp_buf.cmd_code != device[devno].last_cmd)
+    {
+      PDBG (bjnp_dbg
+	    (LOG_CRIT,
+	     "bjnp_recv_header: ERROR - Received response has cmd code %d, expected %d\n",
+	     resp_buf.cmd_code, device[devno].last_cmd));
+      return SANE_STATUS_IO_ERROR;
+    }
+
+  if (ntohs (resp_buf.seq_no) != (uint16_t) device[devno].serial)
+    {
+      PDBG (bjnp_dbg
+	    (LOG_CRIT,
+	     "bjnp_recv_header: ERROR - Received response has serial %d, expected %d\n",
+	     (int) ntohs (resp_buf.seq_no), (int) device[devno].serial));
+      return SANE_STATUS_IO_ERROR;
+    }
+
+  /* got response header back, retrieve length of payload */
+
+
+  *payload_size = ntohl (resp_buf.payload_len);
+  PDBG (bjnp_dbg
+	(LOG_DEBUG, "bjnp_recv_header: TCP response header(payload data = %ld bytes):\n",
+	 *payload_size) );
+  PDBG (bjnp_hexdump
+	(LOG_DEBUG2, (char *) &resp_buf, sizeof (struct BJNP_command)));
+  return SANE_STATUS_GOOD;
+}
+
+static int
+bjnp_init_device_structure(int dn, bjnp_sockaddr_t *sa, bjnp_protocol_defs_t *protocol_defs, int ip_timeout)
+{
+  /* initialize device structure */
+
+  char name[BJNP_HOST_MAX];
+
+  device[dn].open = 0;
+#ifdef PIXMA_BJNP_USE_STATUS
+  device[dn].polling_status = BJNP_POLL_STOPPED;
+  device[dn].dialog = 0;
+  device[dn].status_key = 0;
+#endif
+  device[dn].protocol = protocol_defs->protocol_version;
+  device[dn].protocol_string = protocol_defs->proto_string;
+  device[dn].tcp_socket = -1;
+
+  device[dn].addr = (bjnp_sockaddr_t *) malloc(sizeof ( bjnp_sockaddr_t) );
+  memset( device[dn].addr, 0, sizeof( bjnp_sockaddr_t ) );
+  memcpy(device[dn].addr, sa, sa_size((bjnp_sockaddr_t *)sa) );
+  device[dn].address_level = get_scanner_name(sa, name);
+  device[dn].session_id = 0;
+  device[dn].serial = -1;
+  device[dn].bjnp_ip_timeout = ip_timeout;
+  device[dn].bjnp_scanner_timeout = 1000;
+  device[dn].scanner_data_left = 0;
+  device[dn].last_cmd = 0;
+  device[dn].blocksize = BJNP_BLOCKSIZE_START;
+  device[dn].last_block = 0;
+  /* fill mac_address */
+
+  if (bjnp_get_scanner_mac_address(dn, device[dn].mac_address) != 0 )
+    {
+      PDBG (bjnp_dbg
+            (LOG_CRIT, "bjnp_init_device_structure: Cannot read mac address, skipping this scanner\n"  ) );
+            device[dn].open = 0;
+      return -1;
+    }
+  device[dn].open = 1;
+  return 0;
+}
+
+static void
+bjnp_free_device_structure( int dn)
+{
+  if (device[dn].addr != NULL)
+    {
+    free (device[dn].addr );
+    device[dn].addr = NULL;
+    }
+  device[dn].open = 0;
+}
+
+static SANE_Status
+bjnp_recv_data (int devno, SANE_Byte * buffer, size_t start_pos, size_t * len)
+{
+/*
+ * This function receives the payload data.
+ * NOTE: len may not exceed SSIZE_MAX (as that is max for recv)
+ *       len will be restricted to SSIZE_MAX to be sure
+ * Returns: number of bytes of payload received from device
+ */
+
+  fd_set input;
+  struct timeval timeout;
+  ssize_t recv_bytes;
+  int terrno;
+  int result;
+  int fd;
+  int attempt;
+
+  PDBG (bjnp_dbg
+	(LOG_DEBUG, "bjnp_recv_data: read response payload (0x%lx bytes max), buffer: 0x%lx, start_pos: 0x%lx\n",
+	 (long) *len, (long) buffer, (long) start_pos));
+
+
+  if (*len == 0)
+    {
+      /* nothing to do */
+      PDBG (bjnp_dbg
+  	    (LOG_DEBUG, "bjnp_recv_data: Nothing to do (%ld bytes requested)\n",
+	     (long) *len));
+      return SANE_STATUS_GOOD;
+    }
+  else if ( *len > SSIZE_MAX )
+    {
+      PDBG (bjnp_dbg
+    	    (LOG_DEBUG, "bjnp_recv_data: WARNING - requested block size (%ld) exceeds maximum, setting to maximum %ld\n",
+	     (long)*len, SSIZE_MAX));
+      *len = SSIZE_MAX;
+    }
+
+  fd = device[devno].tcp_socket;
+  attempt = 0;
+  do
+    {
+      /* wait for data to be received, retry on a signal being received */
+      FD_ZERO (&input);
+      FD_SET (fd, &input);
+      timeout.tv_sec = device[devno].bjnp_ip_timeout /1000;
+      timeout.tv_usec = device[devno].bjnp_ip_timeout %1000;
+    }
+  while (((result = select (fd + 1, &input, NULL, NULL, &timeout)) <= 0) &&
+	 (errno == EINTR) && (attempt++ < BJNP_MAX_SELECT_ATTEMPTS));
+
+  if (result < 0)
+    {
+      terrno = errno;
+      PDBG (bjnp_dbg (LOG_CRIT,
+		       "bjnp_recv_data: ERROR - could not read response payload (select failed): %s!\n",
+		       strerror (errno)));
+      errno = terrno;
+      *len = 0;
+      return SANE_STATUS_IO_ERROR;
+    }
+  else if (result == 0)
+    {
+      terrno = errno;
+      PDBG (bjnp_dbg (LOG_CRIT,
+		"bjnp_recv_data: ERROR - could not read response payload (select timed out after %d ms)!\n",
+		device[devno].bjnp_ip_timeout) );
+      errno = terrno;
+      *len = 0;
+      return SANE_STATUS_IO_ERROR;
+    }
+
+  if ((recv_bytes = recv (fd, buffer + start_pos, *len, 0)) < 0)
+    {
+      terrno = errno;
+      PDBG (bjnp_dbg (LOG_CRIT,
+		       "bjnp_recv_data: ERROR - could not read response payload (%ld + %ld = %ld) (recv): %s!\n",
+		       (long) buffer, (long) start_pos, (long) buffer + start_pos, strerror (errno)));
+      errno = terrno;
+      *len = 0;
+      return SANE_STATUS_IO_ERROR;
+    }
+  PDBG (bjnp_dbg (LOG_DEBUG2, "bjnp_recv_data: Received TCP response payload (%ld bytes):\n",
+		   (unsigned long) recv_bytes));
+  PDBG (bjnp_hexdump (LOG_DEBUG2, buffer, recv_bytes));
+
+  *len = recv_bytes;
+  return SANE_STATUS_GOOD;
+}
+
+static BJNP_Status
+bjnp_allocate_device (SANE_String_Const devname,
+                      SANE_Int * dn, char *resulting_host)
+{
+  char method[BJNP_METHOD_MAX];
+  char host[BJNP_HOST_MAX];
+  char port[BJNP_PORT_MAX] = "";
+  char args[BJNP_ARGS_MAX];
+  bjnp_protocol_defs_t *protocol_defs;
+  struct addrinfo *res, *cur;
+  struct addrinfo hints;
+  int result;
+  int i;
+  int ip_timeout = BJNP_TIMEOUT_DEFAULT;
+
+  PDBG (bjnp_dbg (LOG_DEBUG, "bjnp_allocate_device(%s) %d\n", devname, bjnp_no_devices));
+
+  if (split_uri (devname, method, host, port, args) != 0)
+    {
+      return BJNP_STATUS_INVAL;
+    }
+
+  if (strlen (args) > 0)
+    {
+      /* get device specific ip timeout if any */
+
+      if (strncmp(args, "timeout=", strlen("timeout=")) == 0)
+        {
+          ip_timeout = atoi(args + strlen("timeout="));
+        } else {
+		PDBG (bjnp_dbg
+	    		(LOG_CRIT,
+				"bjnp_allocate_device: ERROR - Unrecognized argument: %s\n",
+	     			devname));
+
+      return BJNP_STATUS_INVAL;
+        }
+    }
+  if ( (protocol_defs = get_protocol_by_method(method)) == NULL)
+    {
+      PDBG (bjnp_dbg
+		(LOG_CRIT, "bjnp_allocate_device: ERROR - URI %s contains invalid method: %s\n",
+		 devname, method));
+      return BJNP_STATUS_INVAL;
+    }
+
+  if (strlen(port) == 0)
+    {
+      sprintf( port, "%d", protocol_defs->default_port );
+    }
+
+  hints.ai_flags = 0;
+#ifdef ENABLE_IPV6
+  hints.ai_family = AF_UNSPEC;
+#else
+  hints.ai_family = AF_INET;
+#endif
+  hints.ai_socktype = SOCK_DGRAM;
+  hints.ai_protocol = 0;
+  hints.ai_addrlen = 0;
+  hints.ai_addr = NULL;
+  hints.ai_canonname = NULL;
+  hints.ai_next = NULL;
+
+  result = getaddrinfo (host, port, &hints, &res );
+  if (result != 0 )
+    {
+      PDBG (bjnp_dbg (LOG_CRIT, "bjnp_allocate_device: ERROR - Cannot resolve host: %s port %s\n", host, port));
+      return SANE_STATUS_INVAL;
+    }
+
+  /* Check if a device number is already allocated to any of the scanner's addresses */
+
+  cur = res;
+  while( cur != NULL)
+    {
+      /* create a new device structure for this address */
+
+      if (bjnp_no_devices == BJNP_NO_DEVICES)
+        {
+          PDBG (bjnp_dbg
+    	    (LOG_CRIT,
+    	     "bjnp_allocate_device: WARNING - Too many devices, ran out of device structures, cannot add %s\n",
+    	     devname));
+          freeaddrinfo(res);
+          return BJNP_STATUS_INVAL;
+        }
+      if (bjnp_init_device_structure( bjnp_no_devices, (bjnp_sockaddr_t *)cur -> ai_addr,
+                                      protocol_defs, ip_timeout) != 0)
+        {
+          /* giving up on this address, try next one if any */
+          cur = cur->ai_next;
+          continue;
+        }
+      for (i = 0; i < bjnp_no_devices; i++)
+        {
+
+          /* Check if found the scanner before, if so we use the best address
+	   * but still make sure the scanner is listed only once.
+	   * We check for matching addresses as wel as matching mac_addresses as
+           * an IPv6 host can have multiple adresses */
+
+          if ( strcmp( device[i].mac_address, device[bjnp_no_devices].mac_address ) == 0 )
+            {
+              if ( device[i].address_level < device[bjnp_no_devices].address_level )
+                {
+                  /* use the new address instead as it is better */
+                  free (device[i].addr);
+                  device[i].addr = device[bjnp_no_devices].addr;
+                  device[bjnp_no_devices].addr = NULL;
+                  device[i].address_level = device[bjnp_no_devices].address_level;
+                }
+
+	      /* Leave timeout values unchanged, as they were probably specified by the user */
+
+              freeaddrinfo(res);
+              *dn = i;
+              bjnp_free_device_structure( bjnp_no_devices);
+              return BJNP_STATUS_ALREADY_ALLOCATED;
+            }
+        }
+      cur = cur->ai_next;
+    }
+  freeaddrinfo(res);
+
+  if (device[bjnp_no_devices].open == 0)
+    {
+      PDBG (bjnp_dbg(LOG_NOTICE, "bjnp_allocate_device: Cannot access scanner, skipping!"));
+      return BJNP_STATUS_INVAL;
+    }
+
+  PDBG (bjnp_dbg (LOG_INFO, "bjnp_allocate_device: Scanner not yet in our list, added it: %s:%s\n", host, port));
+
+  /* Commit new device structure */
+
+  *dn = bjnp_no_devices;
+  bjnp_no_devices++;
+
+  /* return hostname if required */
+
+  if (resulting_host != NULL)
+    {
+      strcpy (resulting_host, host);
+    }
+
+  return BJNP_STATUS_GOOD;
+}
+
+static void add_scanner(SANE_Int *dev_no,
+                        const char *uri,
+			SANE_Status (*attach_bjnp)
+			              (SANE_String_Const devname,
+			               SANE_String_Const serial,
+			               const struct pixma_config_t *cfg),
+                       const struct pixma_config_t *const pixma_devices[])
+
+{
+  char scanner_host[BJNP_HOST_MAX];
+  char serial[BJNP_SERIAL_MAX];
+  char makemodel[BJNP_MODEL_MAX];
+  const struct pixma_config_t *cfg = NULL;
+
+  /* Allocate device structure for scanner */
+  switch (bjnp_allocate_device (uri, dev_no, scanner_host))
+    {
+      case BJNP_STATUS_GOOD:
+        if (get_scanner_id (*dev_no, makemodel) != 0)
+          {
+            PDBG (bjnp_dbg (LOG_CRIT, "add_scanner: ERROR - Cannot read scanner make & model: %s\n",
+                             uri));
+          }
+        else
+          {
+            /*
+             * fetch scanner configuration
+             */
+            if ((cfg = lookup_scanner(makemodel, pixma_devices)) == (struct pixma_config_t *)NULL)
+              {
+                 PDBG (bjnp_dbg (LOG_CRIT, "add_scanner: Scanner %s is not supported, model is unknown! Please report upstream\n", makemodel));
+                 break;
+              }
+
+            /*
+             * inform caller of found scanner
+             */
+
+             determine_scanner_serial (scanner_host, device[*dev_no].mac_address, serial);
+
+             switch (attach_bjnp (uri, serial, cfg))
+             {
+               case SANE_STATUS_GOOD:
+                 PDBG (bjnp_dbg (LOG_NOTICE, "add_scanner: New scanner added: %s, serial %s, mac address: %s.\n",
+	                         uri, serial, device[*dev_no].mac_address));
+                 break;
+               default:
+                 PDBG (bjnp_dbg (LOG_CRIT, "add_scanner: unexpected error (out of memory?), adding %s\n", makemodel));
+            }
+          }
+
+        break;
+      case BJNP_STATUS_ALREADY_ALLOCATED:
+        PDBG (bjnp_dbg (LOG_NOTICE, "add_scanner: Scanner at %s was added before, good!\n",
+	                 uri));
+        break;
+
+      case BJNP_STATUS_INVAL:
+        PDBG (bjnp_dbg (LOG_NOTICE, "add_scanner: Scanner at %s can not be added\n",
+	                 uri));
+        break;
+    }
+}
+
+int add_timeout_to_uri(char *uri, int timeout, int max_len)
+{
+  char method[BJNP_METHOD_MAX];
+  char host[BJNP_HOST_MAX];
+  char port_str[BJNP_PORT_MAX];
+  char args[BJNP_HOST_MAX];
+  int port;
+  bjnp_protocol_defs_t *proto_struct;
+
+  if (split_uri(uri, method, host, port_str, args ) != 0)
+    {
+      return -1;
+    }
+
+  port = atoi(port_str);
+
+  if (port == 0)
+    {
+      proto_struct = get_protocol_by_method(method);
+      if (proto_struct == NULL)
+        {
+          PDBG (bjnp_dbg (LOG_NOTICE, "uri: %s: Method %s cannot be recognized\n", uri,  method));
+        }
+      else
+        {
+          port = proto_struct-> default_port;
+        }
+    }
+
+  /* add timeout value only if missing in URI */
+
+  if (strstr(args, "timeout=") == NULL)
+    {
+      sprintf(args, "timeout=%d", timeout);
+    }
+
+  snprintf(uri, max_len -1, "%s://%s:%d/%s", method,host, port, args);
+  uri[max_len - 1] = '\0';
+  return 0;
+}
+
+/** Public functions **/
+
+/** Initialize sanei_bjnp.
+ *
+ * Call this before any other sanei_bjnp function.
+ */
+extern void
+sanei_bjnp_init (void)
+{
+  DBG_INIT();
+  bjnp_no_devices = 0;
+}
+
+/**
+ * Find devices that implement the bjnp protocol
+ *
+ * The function attach is called for every device which has been found.
+ *
+ * @param attach attach function
+ *
+ * @return SANE_STATUS_GOOD - on success (even if no scanner was found)
+ */
+extern SANE_Status
+sanei_bjnp_find_devices (const char **conf_devices,
+			 SANE_Status (*attach_bjnp)
+			     (SANE_String_Const devname,
+			      SANE_String_Const serial,
+			      const struct pixma_config_t *cfg),
+			 const struct pixma_config_t *const pixma_devices[])
+{
+  int numbytes = 0;
+  struct BJNP_command cmd;
+  unsigned char resp_buf[2048];
+  struct DISCOVER_RESPONSE *disc_resp = ( struct DISCOVER_RESPONSE *) & resp_buf;
+  int socket_fd[BJNP_SOCK_MAX];
+  int no_sockets;
+  int i;
+  int j;
+  int attempt;
+  int last_socketfd = 0;
+  fd_set fdset;
+  fd_set active_fdset;
+  struct timeval timeout;
+  char scanner_host[HOST_NAME_MAX];
+  char uri[HOST_NAME_MAX + 32];
+  int dev_no;
+  int port;
+  int auto_detect = 1;
+  int timeout_default = BJNP_TIMEOUT_DEFAULT;
+  bjnp_sockaddr_t broadcast_addr[BJNP_SOCK_MAX];
+  bjnp_sockaddr_t scanner_sa;
+  socklen_t socklen;
+  bjnp_protocol_defs_t *protocol_defs;
+
+  memset( broadcast_addr, 0, sizeof( broadcast_addr) );
+  memset( &scanner_sa, 0 ,sizeof( scanner_sa ) );
+  PDBG (bjnp_dbg (LOG_INFO, "sanei_bjnp_find_devices, pixma backend version: %d.%d.%d\n",
+	PIXMA_VERSION_MAJOR, PIXMA_VERSION_MINOR, PIXMA_VERSION_BUILD));
+  bjnp_no_devices = 0;
+
+  for (i=0; i < BJNP_SOCK_MAX; i++)
+    {
+      socket_fd[i] = -1;
+    }
+
+  /* parse config file */
+
+  if (conf_devices[0] != NULL)
+    {
+      if (strcmp(conf_devices[0], "networking=no") == 0)
+        {
+          /* networking=no may only occur on the first non-commented line */
+
+          PDBG (bjnp_dbg( LOG_DEBUG, "sanei_bjnp_find_devices: Networked scanner detection is disabled in configuration file.\n" ) );
+          return SANE_STATUS_GOOD;
+        }
+      /* parse configuration file */
+
+      for (i = 0; conf_devices[i] != NULL; i++)
+        {
+          if (strncmp(conf_devices[i], "bjnp-timeout=", strlen("bjnp-timeout="))== 0)
+            {
+	      timeout_default = atoi(conf_devices[i] + strlen("bjnp-timeout=") );
+	      PDBG ( bjnp_dbg (LOG_DEBUG, "Set new default timeout value: %d ms.", timeout_default));
+	      continue;
+	    }
+	  else if (strncmp(conf_devices[i], "auto_detection=no", strlen("auto_detection=no"))== 0)
+            {
+              auto_detect = 0;
+	      PDBG ( bjnp_dbg (LOG_DEBUG, "sanei_bjnp_find_devices: auto detection of scanners disabled"));
+	      continue;
+	    }
+	  else
+            {
+              PDBG (bjnp_dbg (LOG_DEBUG, "sanei_bjnp_find_devices: Adding scanner from pixma.conf: %s\n", conf_devices[i]));
+              memcpy(uri, conf_devices[i], sizeof(uri));
+              add_timeout_to_uri(uri, timeout_default, sizeof(uri));
+              add_scanner(&dev_no, uri, attach_bjnp, pixma_devices);
+	    }
+        }
+      PDBG (bjnp_dbg (LOG_DEBUG, "sanei_bjnp_find_devices: Added all specified scanners.\n"));
+    }
+  else
+    {
+      PDBG (bjnp_dbg( LOG_DEBUG, "sanei_bjnp_find_devices: Configuration file is empty, No devices specified.\n" ) );
+    }
+
+  if (auto_detect == 0)
+    {
+      return SANE_STATUS_GOOD;
+    }
+  /*
+   * Send UDP DISCOVER to discover scanners and return the list of scanners found
+   */
+
+  PDBG (bjnp_dbg( LOG_DEBUG, "sanei_bjnp_find_devices: Start auto-detection.\n" ) );
+  FD_ZERO (&fdset);
+
+  no_sockets = 0;
+#ifdef HAVE_IFADDRS_H
+  {
+    struct ifaddrs *interfaces = NULL;
+    struct ifaddrs *interface;
+    getifaddrs (&interfaces);
+
+    /* create a socket for each suitable interface */
+
+    interface = interfaces;
+    while ((no_sockets < BJNP_SOCK_MAX) && (interface != NULL))
+      {
+        if ( ! (interface -> ifa_flags & IFF_POINTOPOINT) &&
+            ( (socket_fd[no_sockets] =
+                      prepare_socket( interface -> ifa_name,
+                                      (bjnp_sockaddr_t *) interface -> ifa_addr,
+                                      (bjnp_sockaddr_t *) interface -> ifa_broadaddr,
+                                      &broadcast_addr[no_sockets] ) ) != -1 ) )
+          {
+            /* track highest used socket for later use in select */
+            if (socket_fd[no_sockets] > last_socketfd)
+              {
+                last_socketfd = socket_fd[no_sockets];
+              }
+            FD_SET (socket_fd[no_sockets], &fdset);
+            no_sockets++;
+          }
+        interface = interface->ifa_next;
+      }
+    freeifaddrs (interfaces);
+  }
+#else
+  /* we have no easy way to find interfaces with their broadcast addresses. */
+  /* use global broadcast and all-hosts instead */
+  {
+    bjnp_sockaddr_t local;
+    bjnp_sockaddr_t bc_addr;
+
+    memset( &local, 0, sizeof( local) );
+    local.ipv4.sin_family = AF_INET;
+    local.ipv4.sin_addr.s_addr = htonl (INADDR_ANY);
+
+    bc_addr.ipv4.sin_family = AF_INET;
+    bc_addr.ipv4.sin_port = htons(0);
+    bc_addr.ipv4.sin_addr.s_addr = htonl (INADDR_BROADCAST);
+
+    socket_fd[no_sockets] = prepare_socket( "any_interface",
+                                   &local,
+                                   &bc_addr,
+                                   &broadcast_addr[no_sockets] );
+    if (socket_fd[no_sockets] >= 0)
+      {
+        FD_SET (socket_fd[no_sockets], &fdset);
+        if (socket_fd[no_sockets] > last_socketfd)
+          {
+            last_socketfd = socket_fd[no_sockets];
+          }
+        no_sockets++;
+      }
+#ifdef ENABLE_IPV6
+    local.ipv6.sin6_family = AF_INET6;
+    local.ipv6.sin6_addr = in6addr_any;
+
+    socket_fd[no_sockets] = prepare_socket( "any_interface",
+                                   &local,
+                                   NULL,
+                                   &broadcast_addr[no_sockets] );
+    if (socket_fd[no_sockets] >= 0)
+      {
+        FD_SET (socket_fd[no_sockets], &fdset);
+        if (socket_fd[no_sockets] > last_socketfd)
+          {
+            last_socketfd = socket_fd[no_sockets];
+          }
+        no_sockets++;
+      }
+#endif
+  }
+#endif
+
+  /* send BJNP_MAX_BROADCAST_ATTEMPTS broadcasts on each prepared socket */
+  for (attempt = 0; attempt < BJNP_MAX_BROADCAST_ATTEMPTS; attempt++)
+    {
+      for ( i=0; i < no_sockets; i++)
+        {
+	  j = 0;
+          while(bjnp_protocol_defs[j].protocol_version != PROTOCOL_NONE)
+	    {
+	      set_cmd_from_string (bjnp_protocol_defs[j].proto_string, &cmd, CMD_UDP_DISCOVER, 0);
+              bjnp_send_broadcast ( socket_fd[i], &broadcast_addr[i],
+                                    bjnp_protocol_defs[j].default_port, cmd, sizeof (cmd));
+	      j++;
+	    }
+	}
+      /* wait for some time between broadcast packets */
+      usleep (BJNP_BROADCAST_INTERVAL * BJNP_USLEEP_MS);
+    }
+
+  /* wait for a UDP response */
+
+  timeout.tv_sec = 0;
+  timeout.tv_usec = BJNP_BC_RESPONSE_TIMEOUT * BJNP_USLEEP_MS;
+
+
+  active_fdset = fdset;
+
+  while (select (last_socketfd + 1, &active_fdset, NULL, NULL, &timeout) > 0)
+    {
+      PDBG (bjnp_dbg (LOG_DEBUG, "sanei_bjnp_find_devices: Select returned, time left %d.%d....\n",
+		       (int) timeout.tv_sec, (int) timeout.tv_usec));
+      for (i = 0; i < no_sockets; i++)
+	{
+	  if (FD_ISSET (socket_fd[i], &active_fdset))
+	    {
+              socklen =  sizeof(scanner_sa);
+	      if ((numbytes =
+		   recvfrom (socket_fd[i], resp_buf, sizeof (resp_buf), 0,
+                             &(scanner_sa.addr), &socklen ) ) == -1)
+		{
+		  PDBG (bjnp_dbg
+			(LOG_INFO, "sanei_find_devices: no data received"));
+		  break;
+		}
+	      else
+		{
+		  PDBG (bjnp_dbg (LOG_DEBUG2, "sanei_find_devices: Discover response:\n"));
+		  PDBG (bjnp_hexdump (LOG_DEBUG2, &resp_buf, numbytes));
+
+		  /* check if something sensible is returned */
+		  protocol_defs = get_protocol_by_proto_string(disc_resp-> response.BJNP_id);
+		  if ( (numbytes < (int)sizeof (struct BJNP_command)) ||
+		       (protocol_defs == NULL))
+		    {
+		      /* not a valid response, assume not a scanner  */
+
+                      char bjnp_id[5];
+                      strncpy(bjnp_id,  disc_resp-> response.BJNP_id, 4);
+                      bjnp_id[4] = '\0';
+                      PDBG (bjnp_dbg (LOG_INFO,
+                        "sanei_find_devices: Invalid discover response! Length = %d, Id = %s\n",
+                        numbytes, bjnp_id ) );
+		      break;
+		    }
+                  if ( !(disc_resp -> response.dev_type & 0x80) )
+                    {
+                      /* not a response, a command from somebody else or */
+                      /* a discover command that we generated */
+                      break;
+                    }
+		};
+
+	      port = get_port_from_sa(scanner_sa);
+	      /* scanner found, get IP-address or hostname */
+              get_scanner_name( &scanner_sa, scanner_host);
+
+	      /* construct URI */
+	      sprintf (uri, "%s://%s:%d/timeout=%d", protocol_defs->method_string, scanner_host,
+		           port, timeout_default);
+
+              add_scanner( &dev_no, uri, attach_bjnp, pixma_devices);
+
+	    }
+	}
+      active_fdset = fdset;
+      timeout.tv_sec = 0;
+      timeout.tv_usec = BJNP_BC_RESPONSE_TIMEOUT * BJNP_USLEEP_MS;
+    }
+  PDBG (bjnp_dbg (LOG_DEBUG, "sanei_find_devices: scanner discovery finished...\n"));
+
+  for (i = 0; i < no_sockets; i++)
+    close (socket_fd[i]);
+
+  return SANE_STATUS_GOOD;
+}
+
+/** Open a BJNP device.
+ *
+ * The device is opened by its name devname and the device number is
+ * returned in dn on success.
+ *
+ * Device names consist of an URI
+ * Where:
+ * type = bjnp
+ * hostname = resolvable name or IP-address
+ * port = 8612 for a scanner
+ * An example could look like this: bjnp://host.domain:8612
+ *
+ * @param devname name of the device to open
+ * @param dn device number
+ *
+ * @return
+ * - SANE_STATUS_GOOD - on success
+ * - SANE_STATUS_ACCESS_DENIED - if the file couldn't be accessed due to
+ *   permissions
+ * - SANE_STATUS_INVAL - on every other error
+ */
+
+extern SANE_Status
+sanei_bjnp_open (SANE_String_Const devname, SANE_Int * dn)
+{
+  int result;
+
+  PDBG (bjnp_dbg (LOG_INFO, "sanei_bjnp_open(%s, %d):\n", devname, *dn));
+
+  result = bjnp_allocate_device (devname, dn, NULL);
+  if ( (result != BJNP_STATUS_GOOD) && (result != BJNP_STATUS_ALREADY_ALLOCATED ) ) {
+    return SANE_STATUS_INVAL;
+  }
+  return SANE_STATUS_GOOD;
+}
+
+/** Close a BJNP device.
+ *
+ * @param dn device number
+ */
+
+void
+sanei_bjnp_close (SANE_Int dn)
+{
+  PDBG (bjnp_dbg (LOG_INFO, "sanei_bjnp_close(%d):\n", dn));
+
+  device[dn].open = 0;
+  sanei_bjnp_deactivate(dn);
+}
+
+/** Activate BJNP device connection
+ *
+ * @param dn device number
+ */
+
+SANE_Status
+sanei_bjnp_activate (SANE_Int dn)
+{
+  char hostname[256];
+  char pid_str[64];
+
+  PDBG (bjnp_dbg (LOG_INFO, "sanei_bjnp_activate (%d)\n", dn));
+  gethostname (hostname, 256);
+  hostname[255] = '\0';
+  sprintf (pid_str, "Process ID = %d", getpid ());
+
+  bjnp_send_job_details (dn, hostname, getusername (), pid_str);
+
+  if (bjnp_open_tcp (dn) != 0)
+    {
+      return SANE_STATUS_INVAL;
+    }
+
+  return SANE_STATUS_GOOD;
+}
+
+/** Deactivate BJNP device connection
+ *
+ * @paran dn device number
+ */
+
+SANE_Status
+sanei_bjnp_deactivate (SANE_Int dn)
+{
+  PDBG (bjnp_dbg (LOG_INFO, "sanei_bjnp_deactivate (%d)\n", dn));
+  if ( device[dn].tcp_socket != -1)
+    {
+      bjnp_finish_job (dn);
+      close (device[dn].tcp_socket);
+      device[dn].tcp_socket = -1;
+    }
+  return SANE_STATUS_GOOD;
+}
+
+/** Set the timeout for interrupt reads.
+ *  we do not use it for bulk reads!
+ * @param timeout the new timeout in ms
+ */
+extern void
+sanei_bjnp_set_timeout (SANE_Int devno, SANE_Int timeout)
+{
+  PDBG (bjnp_dbg (LOG_INFO, "bjnp_set_timeout to %d\n",
+        timeout));
+
+  device[devno].bjnp_scanner_timeout = timeout;
+}
+
+/** Initiate a bulk transfer read.
+ *
+ * Read up to size bytes from the device to buffer. After the read, size
+ * contains the number of bytes actually read.
+ *
+ * @param dn device number
+ * @param buffer buffer to store read data in
+ * @param size size of the data
+ *
+ * @return
+ * - SANE_STATUS_GOOD - on succes
+ * - SANE_STATUS_EOF - if zero bytes have been read
+ * - SANE_STATUS_IO_ERROR - if an error occured during the read
+ * - SANE_STATUS_INVAL - on every other error
+ *
+ */
+
+extern SANE_Status
+sanei_bjnp_read_bulk (SANE_Int dn, SANE_Byte * buffer, size_t * size)
+{
+  SANE_Status result;
+  SANE_Status error;
+  size_t recvd;
+  size_t read_size;
+  size_t read_size_max;
+  size_t requested;
+
+  PDBG (bjnp_dbg
+	(LOG_INFO, "bjnp_read_bulk(dn=%d, bufferptr=%lx, 0x%lx = %ld)\n", dn,
+	 (long) buffer, (unsigned long) *size, (unsigned long) *size));
+
+  recvd = 0;
+  requested = *size;
+
+  PDBG (bjnp_dbg
+	(LOG_DEBUG, "bjnp_read_bulk: 0x%lx = %ld bytes available at start\n",
+	 (unsigned long) device[dn].scanner_data_left,
+	 (unsigned long) device[dn].scanner_data_left ) );
+
+  while ( (recvd < requested) && !( device[dn].last_block && (device[dn].scanner_data_left == 0)) )
+    {
+      PDBG (bjnp_dbg
+	    (LOG_DEBUG,
+	     "bjnp_read_bulk: Already received 0x%lx = %ld bytes, backend requested 0x%lx = %ld bytes\n",
+	     (unsigned long) recvd, (unsigned long) recvd,
+	     (unsigned long) requested, (unsigned long)requested ));
+
+      /* Check first if there is data in flight from the scanner */
+
+      if (device[dn].scanner_data_left == 0)
+        {
+	  /* There is no data in flight from the scanner, send new read request */
+
+          PDBG (bjnp_dbg (LOG_DEBUG,
+                          "bjnp_read_bulk: No (more) scanner data available, requesting more( blocksize = %ld = %lx\n",
+                          (long int) device[dn].blocksize, (long int) device[dn].blocksize ));
+
+          if ((error = bjnp_send_read_request (dn)) != SANE_STATUS_GOOD)
+            {
+              *size = recvd;
+              return SANE_STATUS_IO_ERROR;
+            }
+          if ( ( error = bjnp_recv_header (dn, &(device[dn].scanner_data_left) )  ) != SANE_STATUS_GOOD)
+            {
+              *size = recvd;
+              return SANE_STATUS_IO_ERROR;
+            }
+          /* correct blocksize if applicable */
+
+          device[dn].blocksize = MAX (device[dn].blocksize, device[dn].scanner_data_left);
+
+          if ( device[dn].scanner_data_left < device[dn].blocksize)
+            {
+              /* the scanner will not react at all to a read request, when no more data is available */
+              /* we now determine end of data by comparing the payload size to the maximun blocksize */
+              /* this block is shorter than blocksize, so after this block we are done */
+
+              device[dn].last_block = 1;
+            }
+        }
+
+      PDBG (bjnp_dbg (LOG_DEBUG, "bjnp_read_bulk: In flight: 0x%lx = %ld bytes available\n",
+		 (unsigned long) device[dn].scanner_data_left,
+		 (unsigned long) device[dn].scanner_data_left));
+
+       /* read as many bytes as needed and available */
+
+      read_size_max = MIN( device[dn].scanner_data_left, (requested - recvd) );
+      read_size = read_size_max;
+
+      PDBG (bjnp_dbg
+	    (LOG_DEBUG,
+	     "bjnp_read_bulk: Try to read 0x%lx = %ld (of max 0x%lx = %ld) bytes\n",
+	     (unsigned long) read_size_max,
+	     (unsigned long) read_size_max,
+	     (unsigned long) device[dn].scanner_data_left,
+	     (unsigned long) device[dn].scanner_data_left) );
+
+      result = bjnp_recv_data (dn, buffer , recvd, &read_size);
+      if (result != SANE_STATUS_GOOD)
+	{
+	  *size = recvd;
+	  return SANE_STATUS_IO_ERROR;
+	}
+      PDBG (bjnp_dbg (LOG_DEBUG, "bjnp_read_bulk: Expected at most %ld bytes, received this time: %ld\n",
+            read_size_max, read_size) );
+
+      device[dn].scanner_data_left = device[dn].scanner_data_left - read_size;
+      recvd = recvd + read_size;
+    }
+
+  PDBG (bjnp_dbg (LOG_DEBUG, "bjnp_read_bulk: %s: Returning %ld bytes, backend expexts %ld\n",
+        (recvd == *size)? "OK": "NOTICE",recvd, *size ) );
+  *size = recvd;
+  if ( *size == 0 )
+    return SANE_STATUS_EOF;
+  return SANE_STATUS_GOOD;
+}
+
+/** Initiate a bulk transfer write.
+ *
+ * Write up to size bytes from buffer to the device. After the write size
+ * contains the number of bytes actually written.
+ *
+ * @param dn device number
+ * @param buffer buffer to write to device
+ * @param size size of the data
+ *
+ * @return
+ * - SANE_STATUS_GOOD - on succes
+ * - SANE_STATUS_IO_ERROR - if an error occured during the write
+ * - SANE_STATUS_INVAL - on every other error
+ */
+
+extern SANE_Status
+sanei_bjnp_write_bulk (SANE_Int dn, const SANE_Byte * buffer, size_t * size)
+{
+  ssize_t sent;
+  size_t recvd;
+  uint32_t buf;
+  size_t payload_size;
+
+  /* Write received data to scanner */
+
+  sent = bjnp_write (dn, buffer, *size);
+  if (sent < 0)
+    return SANE_STATUS_IO_ERROR;
+  if (sent != (int) *size)
+    {
+      PDBG (bjnp_dbg
+	    (LOG_CRIT, "sanei_bjnp_write_bulk: ERROR - Sent only %ld bytes to scanner, expected %ld!!\n",
+	     (unsigned long) sent, (unsigned long) *size));
+      return SANE_STATUS_IO_ERROR;
+    }
+
+  if (bjnp_recv_header (dn, &payload_size) != SANE_STATUS_GOOD)
+    {
+      PDBG (bjnp_dbg (LOG_CRIT, "sanei_bjnp_write_bulk: ERROR - Could not read response to command!\n"));
+      return SANE_STATUS_IO_ERROR;
+    }
+
+  if (payload_size != 4)
+    {
+      PDBG (bjnp_dbg (LOG_CRIT,
+		       "sanei_bjnp_write_bulk: ERROR - Scanner length of write confirmation = 0x%lx bytes = %ld, expected %d!!\n",
+		       (unsigned long) payload_size,
+		       (unsigned long) payload_size, 4));
+      return SANE_STATUS_IO_ERROR;
+    }
+  recvd = payload_size;
+  if ((bjnp_recv_data (dn, (unsigned char *) &buf, 0, &recvd) !=
+       SANE_STATUS_GOOD) || (recvd != payload_size))
+    {
+      PDBG (bjnp_dbg (LOG_CRIT,
+		       "sanei_bjnp_write_bulk: ERROR - Could not read length of data confirmed by device\n"));
+      return SANE_STATUS_IO_ERROR;
+    }
+  recvd = ntohl (buf);
+  if (recvd != *size)
+    {
+      PDBG (bjnp_dbg
+	    (LOG_CRIT, "sanei_bjnp_write_bulk: ERROR - Scanner confirmed %ld bytes, expected %ld!!\n",
+	     (unsigned long) recvd, (unsigned long) *size));
+      return SANE_STATUS_IO_ERROR;
+    }
+  /* we can expect data from the scanner */
+
+  device[dn].last_block = 0;
+
+  return SANE_STATUS_GOOD;
+}
+
+/** Initiate a interrupt transfer read.
+ *
+ * Read up to size bytes from the interrupt endpoint from the device to
+ * buffer. After the read, size contains the number of bytes actually read.
+ *
+ * @param dn device number
+ * @param buffer buffer to store read data in
+ * @param size size of the data
+ *
+ * @return
+ * - SANE_STATUS_GOOD - on succes
+ * - SANE_STATUS_EOF - if zero bytes have been read
+ * - SANE_STATUS_IO_ERROR - if an error occured during the read
+ * - SANE_STATUS_INVAL - on every other error
+ *
+ */
+
+extern SANE_Status
+sanei_bjnp_read_int (SANE_Int dn, SANE_Byte * buffer, size_t * size)
+{
+#ifndef PIXMA_BJNP_USE_STATUS
+  PDBG (bjnp_dbg
+	(LOG_INFO, "bjnp_read_int(%d, bufferptr, 0x%lx = %ld):\n", dn,
+	 (unsigned long) *size, (unsigned long) *size));
+
+  memset (buffer, 0, *size);
+  sleep (1);
+  return SANE_STATUS_IO_ERROR;
+#else
+
+  char hostname[256];
+  int resp_len;
+  int timeout;
+  int interval;
+
+  PDBG (bjnp_dbg
+	(LOG_INFO, "bjnp_read_int(%d, bufferptr, 0x%lx = %ld):\n", dn,
+	 (unsigned long) *size, (unsigned long) *size));
+
+  memset (buffer, 0, *size);
+
+  gethostname (hostname, 32);
+  hostname[32] = '\0';
+
+
+  switch (device[dn].polling_status)
+    {
+    case BJNP_POLL_STOPPED:
+
+      /* establish dialog */
+
+      if ( (bjnp_poll_scanner (dn, 0, hostname, getusername (), buffer, *size ) != 0) ||
+           (bjnp_poll_scanner (dn, 1, hostname, getusername (), buffer, *size ) != 0) )
+        {
+	  PDBG (bjnp_dbg (LOG_NOTICE, "bjnp_read_int: WARNING - Failed to setup read_intr dialog with device!\n"));
+          device[dn].dialog = 0;
+          device[dn].status_key = 0;
+          return SANE_STATUS_IO_ERROR;
+        }
+      device[dn].polling_status = BJNP_POLL_STARTED;
+
+      /* fall through */
+    case BJNP_POLL_STARTED:
+      /* we use only seonds (rounded up) accuracy between poll attempts */
+      timeout = device[dn].bjnp_scanner_timeout /1000 + 1;
+      if (device[dn].bjnp_scanner_timeout %1000 > 0)
+        {
+	  timeout++;
+
+	}
+      interval = 1;
+      do
+        {
+          if ( (resp_len = bjnp_poll_scanner (dn, 2, hostname, getusername (), buffer, *size ) ) < 0 )
+            {
+              PDBG (bjnp_dbg (LOG_NOTICE, "bjnp_read_int: Poll failed, Restarting polling dialog!\n"));
+              device[dn].polling_status = BJNP_POLL_STOPPED;
+              *size = 0;
+              return SANE_STATUS_EOF;
+            }
+          *size = (size_t) resp_len;
+          if ( resp_len > 0 )
+            {
+              device[dn].polling_status = BJNP_POLL_STATUS_RECEIVED;
+              return SANE_STATUS_GOOD;
+            }
+          timeout = timeout - interval;
+	  if (timeout <= 0)
+	    return SANE_STATUS_EOF;
+          sleep(interval);
+        } while ( timeout > 0 ) ;
+      break;
+    case BJNP_POLL_STATUS_RECEIVED:
+       if ( (resp_len = bjnp_poll_scanner (dn, 5, hostname, getusername (), buffer, *size ) ) < 0 )
+        {
+          PDBG (bjnp_dbg (LOG_NOTICE, "bjnp_read_int: Restarting polling dialog!\n"));
+          device[dn].polling_status = BJNP_POLL_STOPPED;
+          *size = 0;
+          break;
+        }
+    }
+  return SANE_STATUS_EOF;
+#endif
+}