Initial import of sane-backends version 1.0.24-1.2

1 files changed, 2255 insertions, 0 deletions

diff --git a/backend/teco3.c b/backend/teco3.c
new file mode 100644
index 0000000..e66d95d
--- /dev/null
+++ b/backend/teco3.c
@@ -0,0 +1,2255 @@
+/* sane - Scanner Access Now Easy.
+
+   Copyright (C) 2002 Frank Zago (sane at zago dot net)
+   
+   This file is part of the SANE package.
+   
+   This program 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.
+   
+   This program 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 this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+   MA 02111-1307, 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. 
+*/
+
+/*
+   $Id$
+   VM3552 (and maybe VM4552 and VM6552)
+*/
+
+/*--------------------------------------------------------------------------*/
+
+#define BUILD 1			/* 2002/08/06 */
+#define BACKEND_NAME teco3
+#define TECO_CONFIG_FILE "teco3.conf"
+
+/*--------------------------------------------------------------------------*/
+
+#include "../include/sane/config.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include "../include/sane/sane.h"
+#include "../include/sane/sanei.h"
+#include "../include/sane/saneopts.h"
+#include "../include/sane/sanei_scsi.h"
+#include "../include/sane/sanei_debug.h"
+#include "../include/sane/sanei_backend.h"
+#include "../include/sane/sanei_config.h"
+#include "../include/lassert.h"
+
+#include "teco3.h"
+
+/*--------------------------------------------------------------------------*/
+
+/* Lists of possible scan modes. */
+static SANE_String_Const scan_mode_list[] = {
+  BLACK_WHITE_STR,
+  GRAY_STR,
+  COLOR_STR,
+  NULL
+};
+
+/*--------------------------------------------------------------------------*/
+
+/* Minimum and maximum width and length supported. */
+static SANE_Range x_range = { SANE_FIX (0), SANE_FIX (8.5 * MM_PER_INCH), 0 };
+static SANE_Range y_range = { SANE_FIX (0), SANE_FIX (14 * MM_PER_INCH), 0 };
+
+/*--------------------------------------------------------------------------*/
+
+/* Gamma range */
+static const SANE_Range gamma_range = {
+  0,				/* minimum */
+  255,				/* maximum */
+  0				/* quantization */
+};
+
+/*--------------------------------------------------------------------------*/
+
+/* List of dithering options. */
+static SANE_String_Const dither_list[] = {
+  "Line art",
+  "2x2",
+  "3x3",
+  "4x4 bayer",
+  "4x4 smooth",
+  "8x8 bayer",
+  "8x8 smooth",
+  "8x8 horizontal",
+  "8x8 vertical",
+  NULL
+};
+static const int dither_val[] = {
+  0x00,
+  0x01,
+  0x02,
+  0x03,
+  0x04,
+  0x05,
+  0x06,
+  0x07,
+  0x08
+};
+
+/*--------------------------------------------------------------------------*/
+
+static const SANE_Range threshold_range = {
+  0,				/* minimum */
+  255,				/* maximum */
+  0				/* quantization */
+};
+
+/*--------------------------------------------------------------------------*/
+
+/* Define the supported scanners and their characteristics. */
+static const struct scanners_supported scanners[] = {
+  {
+   6, "TECO VM3552",
+   TECO_VM3552,
+   "Relisys", "Scorpio",
+   {1, 1200, 1},		/* resolution range */
+   300, 1200			/* max x and Y resolution */
+   }
+};
+
+/*--------------------------------------------------------------------------*/
+
+/* List of scanner attached. */
+static Teco_Scanner *first_dev = NULL;
+static int num_devices = 0;
+static const SANE_Device **devlist = NULL;
+
+
+/* Local functions. */
+
+/* Display a buffer in the log. */
+static void
+hexdump (int level, const char *comment, unsigned char *p, int l)
+{
+  int i;
+  char line[128];
+  char *ptr;
+  char asc_buf[17];
+  char *asc_ptr;
+
+  DBG (level, "%s\n", comment);
+
+  ptr = line;
+  *ptr = '\0';
+  asc_ptr = asc_buf;
+  *asc_ptr = '\0';
+
+  for (i = 0; i < l; i++, p++)
+    {
+      if ((i % 16) == 0)
+	{
+	  if (ptr != line)
+	    {
+	      DBG (level, "%s    %s\n", line, asc_buf);
+	      ptr = line;
+	      *ptr = '\0';
+	      asc_ptr = asc_buf;
+	      *asc_ptr = '\0';
+	    }
+	  sprintf (ptr, "%3.3d:", i);
+	  ptr += 4;
+	}
+      ptr += sprintf (ptr, " %2.2x", *p);
+      if (*p >= 32 && *p <= 127)
+	{
+	  asc_ptr += sprintf (asc_ptr, "%c", *p);
+	}
+      else
+	{
+	  asc_ptr += sprintf (asc_ptr, ".");
+	}
+    }
+  *ptr = '\0';
+  DBG (level, "%s    %s\n", line, asc_buf);
+}
+
+/* Returns the length of the longest string, including the terminating
+ * character. */
+static size_t
+max_string_size (SANE_String_Const strings[])
+{
+  size_t size, max_size = 0;
+  int i;
+
+  for (i = 0; strings[i]; ++i)
+    {
+      size = strlen (strings[i]) + 1;
+      if (size > max_size)
+	{
+	  max_size = size;
+	}
+    }
+
+  return max_size;
+}
+
+/* Lookup a string list from one array and return its index. */
+static int
+get_string_list_index (SANE_String_Const list[], SANE_String_Const name)
+{
+  int index;
+
+  index = 0;
+  while (list[index] != NULL)
+    {
+      if (strcmp (list[index], name) == 0)
+	{
+	  return (index);
+	}
+      index++;
+    }
+
+  DBG (DBG_error, "name %s not found in list\n", name);
+
+  assert (0 == 1);		/* bug in backend, core dump */
+
+  return (-1);
+}
+
+/* Initialize a scanner entry. Return an allocated scanner with some
+ * preset values. */
+static Teco_Scanner *
+teco_init (void)
+{
+  Teco_Scanner *dev;
+
+  DBG (DBG_proc, "teco_init: enter\n");
+
+  /* Allocate a new scanner entry. */
+  dev = malloc (sizeof (Teco_Scanner));
+  if (dev == NULL)
+    {
+      return NULL;
+    }
+
+  memset (dev, 0, sizeof (Teco_Scanner));
+
+  /* Allocate the buffer used to transfer the SCSI data. */
+  dev->buffer_size = 64 * 1024;
+  dev->buffer = malloc (dev->buffer_size);
+  if (dev->buffer == NULL)
+    {
+      free (dev);
+      return NULL;
+    }
+
+  dev->sfd = -1;
+
+  DBG (DBG_proc, "teco_init: exit\n");
+
+  return (dev);
+}
+
+/* Closes an open scanner. */
+static void
+teco_close (Teco_Scanner * dev)
+{
+  DBG (DBG_proc, "teco_close: enter\n");
+
+  if (dev->sfd != -1)
+    {
+      sanei_scsi_close (dev->sfd);
+      dev->sfd = -1;
+    }
+
+  DBG (DBG_proc, "teco_close: exit\n");
+}
+
+/* Frees the memory used by a scanner. */
+static void
+teco_free (Teco_Scanner * dev)
+{
+  int i;
+
+  DBG (DBG_proc, "teco_free: enter\n");
+
+  if (dev == NULL)
+    return;
+
+  teco_close (dev);
+  if (dev->devicename)
+    {
+      free (dev->devicename);
+    }
+  if (dev->buffer)
+    {
+      free (dev->buffer);
+    }
+  if (dev->image)
+    {
+      free (dev->image);
+    }
+  for (i = 1; i < OPT_NUM_OPTIONS; i++)
+    {
+      if (dev->opt[i].type == SANE_TYPE_STRING && dev->val[i].s)
+	{
+	  free (dev->val[i].s);
+	}
+    }
+
+  free (dev);
+
+  DBG (DBG_proc, "teco_free: exit\n");
+}
+
+/* Inquiry a device and returns TRUE if is supported. */
+static int
+teco_identify_scanner (Teco_Scanner * dev)
+{
+  CDB cdb;
+  SANE_Status status;
+  size_t size;
+  int i;
+
+  DBG (DBG_proc, "teco_identify_scanner: enter\n");
+
+  size = 5;
+  MKSCSI_INQUIRY (cdb, size);
+  status = sanei_scsi_cmd2 (dev->sfd, cdb.data, cdb.len,
+			    NULL, 0, dev->buffer, &size);
+
+  if (status)
+    {
+      DBG (DBG_error,
+	   "teco_identify_scanner: inquiry failed with status %s\n",
+	   sane_strstatus (status));
+      return (SANE_FALSE);
+    }
+
+  size = dev->buffer[4] + 5;	/* total length of the inquiry data */
+
+  if (size < 53)
+    {
+      DBG (DBG_error,
+	   "teco_identify_scanner: not enough data to identify device\n");
+      return (SANE_FALSE);
+    }
+
+  MKSCSI_INQUIRY (cdb, size);
+  status = sanei_scsi_cmd2 (dev->sfd, cdb.data, cdb.len,
+			    NULL, 0, dev->buffer, &size);
+
+  if (status)
+    {
+      DBG (DBG_error,
+	   "teco_identify_scanner: inquiry failed with status %s\n",
+	   sane_strstatus (status));
+      return (SANE_FALSE);
+    }
+
+  hexdump (DBG_info2, "inquiry", dev->buffer, size);
+
+  dev->scsi_type = dev->buffer[0] & 0x1f;
+  memcpy (dev->scsi_vendor, dev->buffer + 0x08, 0x08);
+  dev->scsi_vendor[0x08] = 0;
+  memcpy (dev->scsi_product, dev->buffer + 0x10, 0x010);
+  dev->scsi_product[0x10] = 0;
+  memcpy (dev->scsi_version, dev->buffer + 0x20, 0x04);
+  dev->scsi_version[0x04] = 0;
+  memcpy (dev->scsi_teco_name, dev->buffer + 0x2A, 0x0B);
+  dev->scsi_teco_name[0x0B] = 0;
+
+  DBG (DBG_info, "device is \"%s\" \"%s\" \"%s\" \"%s\"\n",
+       dev->scsi_vendor, dev->scsi_product, dev->scsi_version,
+       dev->scsi_teco_name);
+
+  /* Lookup through the supported scanners table to find if this
+   * backend supports that one. */
+  for (i = 0; i < NELEMS (scanners); i++)
+    {
+
+      if (dev->scsi_type == scanners[i].scsi_type &&
+	  strcmp (dev->scsi_teco_name, scanners[i].scsi_teco_name) == 0)
+	{
+
+	  DBG (DBG_error, "teco_identify_scanner: scanner supported\n");
+
+	  dev->def = &(scanners[i]);
+
+	  return (SANE_TRUE);
+	}
+    }
+
+  DBG (DBG_proc, "teco_identify_scanner: exit, device not supported\n");
+
+  return (SANE_FALSE);
+}
+
+/* SCSI sense handler. Callback for SANE.
+ * These scanners never set asc or ascq. */
+static SANE_Status
+teco_sense_handler (int __sane_unused__ scsi_fd, unsigned char *result, void __sane_unused__ *arg)
+{
+  int sensekey;
+  int len;
+
+  DBG (DBG_proc, "teco_sense_handler: enter\n");
+
+  sensekey = get_RS_sense_key (result);
+  len = 7 + get_RS_additional_length (result);
+
+  hexdump (DBG_info2, "sense", result, len);
+
+  if (get_RS_error_code (result) != 0x70)
+    {
+      DBG (DBG_error,
+	   "teco_sense_handler: invalid sense key error code (%d)\n",
+	   get_RS_error_code (result));
+
+      return SANE_STATUS_IO_ERROR;
+    }
+
+  if (len < 14)
+    {
+      DBG (DBG_error, "teco_sense_handler: sense too short, no ASC/ASCQ\n");
+
+      return SANE_STATUS_IO_ERROR;
+    }
+
+  DBG (DBG_sense, "teco_sense_handler: sense=%d\n", sensekey);
+
+  if (sensekey == 0x00)
+    {
+      return SANE_STATUS_GOOD;
+    }
+
+  return SANE_STATUS_IO_ERROR;
+}
+
+/* Set a window. */
+static SANE_Status
+teco_set_window (Teco_Scanner * dev)
+{
+  size_t window_size;
+  CDB cdb;
+  unsigned char window[255];
+  SANE_Status status;
+  int i;
+
+  DBG (DBG_proc, "teco_set_window: enter\n");
+
+  /* size of the whole windows block */
+  switch (dev->def->tecoref)
+    {
+    case TECO_VM3552:
+      window_size = 69;
+      break;
+	default:
+		assert(0);
+    }
+
+
+  MKSCSI_SET_WINDOW (cdb, window_size);
+
+  memset (window, 0, window_size);
+
+  /* size of the windows descriptor block */
+  window[7] = window_size - 8;
+
+  /* X and Y resolution */
+  Ito16 (dev->x_resolution, &window[10]);
+  Ito16 (dev->y_resolution, &window[12]);
+
+  /* Upper Left (X,Y) */
+  Ito32 (dev->x_tl, &window[14]);
+  Ito32 (dev->y_tl, &window[18]);
+
+  /* Width and length */
+  Ito32 (dev->width, &window[22]);
+  Ito32 (dev->length, &window[26]);
+
+  /* Image Composition */
+  switch (dev->scan_mode)
+    {
+    case TECO_BW:
+      window[31] = dev->val[OPT_THRESHOLD].w;
+      window[33] = 0x00;
+      i = get_string_list_index (dither_list, dev->val[OPT_DITHER].s);
+      window[36] = dither_val[i];
+      break;
+    case TECO_GRAYSCALE:
+	  window[31] = 0x80;
+      window[33] = 0x02;
+      break;
+    case TECO_COLOR:
+	  window[31] = 0x80;
+      window[33] = 0x05;
+      break;
+    }
+
+  /* Depth */
+  window[34] = dev->depth;
+
+  /* Unknown - invariants */
+  window[37] = 0x80;
+
+  switch (dev->def->tecoref)
+    {
+    case TECO_VM3552:
+      window[48] = 0x01;
+      window[50] = 0x02;
+      window[53] = 0xff;
+      window[57] = 0xff;
+      window[61] = 0xff;
+      window[65] = 0xff;
+      break;
+    }
+
+  hexdump (DBG_info2, "windows", window, window_size);
+
+  status = sanei_scsi_cmd2 (dev->sfd, cdb.data, cdb.len,
+			    window, window_size, NULL, NULL);
+
+  DBG (DBG_proc, "teco_set_window: exit, status=%d\n", status);
+
+  return status;
+}
+
+/* Park the CCD */
+static SANE_Status
+teco_reset_window (Teco_Scanner * dev)
+{
+  SANE_Status status;
+  CDB cdb;
+
+  DBG (DBG_proc, "teco_reset_window: enter\n");
+
+  MKSCSI_OBJECT_POSITION (cdb, 0);
+
+  hexdump (DBG_info2, "CDB:", cdb.data, cdb.len);
+  status = sanei_scsi_cmd2 (dev->sfd, cdb.data, cdb.len, NULL, 0, NULL, NULL);
+
+  DBG (DBG_proc, "teco_reset_window: leave, status=%d\n", status);
+
+  return status;
+}
+
+/* Return the number of byte that can be read. */
+static SANE_Status
+get_filled_data_length (Teco_Scanner * dev, size_t * to_read)
+{
+  size_t size;
+  CDB cdb;
+  SANE_Status status;
+
+  DBG (DBG_proc, "get_filled_data_length: enter\n");
+
+  *to_read = 0;
+
+  size = 0x12;
+  MKSCSI_GET_DATA_BUFFER_STATUS (cdb, 1, size);
+  status = sanei_scsi_cmd2 (dev->sfd, cdb.data, cdb.len,
+			    NULL, 0, dev->buffer, &size);
+
+  if (size < 0x10)
+    {
+      DBG (DBG_error,
+	   "get_filled_data_length: not enough data returned (%ld)\n",
+	   (long) size);
+    }
+
+  hexdump (DBG_info2, "get_filled_data_length return", dev->buffer, size);
+
+  *to_read = B24TOI (&dev->buffer[9]);
+
+  DBG (DBG_info, "%d %d  -  %d %d\n",
+       dev->params.lines, B16TOI (&dev->buffer[12]),
+       dev->params.bytes_per_line, B16TOI (&dev->buffer[14]));
+
+  if (dev->real_bytes_left == 0)
+    {
+
+      DBG (DBG_error,
+	   "get_filled_data_length: internal scanner buffer size is %d bytes\n",
+	   B24TOI (&dev->buffer[6]));
+
+      /* Beginning of a scan. */
+      dev->params.lines = B16TOI (&dev->buffer[12]);
+      dev->bytes_per_raster = B16TOI (&dev->buffer[14]);
+
+      switch (dev->scan_mode)
+	{
+	case TECO_BW:
+	  dev->params.bytes_per_line = B16TOI (&dev->buffer[14]);
+	  dev->params.pixels_per_line = dev->params.bytes_per_line * 8;
+	  break;
+
+	case TECO_GRAYSCALE:
+	  dev->params.pixels_per_line = B16TOI (&dev->buffer[14]);
+	  dev->params.bytes_per_line = dev->params.pixels_per_line;
+	  break;
+
+	case TECO_COLOR:
+	  dev->params.pixels_per_line = B16TOI (&dev->buffer[14]);
+	  dev->params.bytes_per_line = dev->params.pixels_per_line * 3;
+	  if (dev->buffer[17] == 0x07)
+	    {
+	      /* There is no RAM extension present. The colors will
+	       * be shifted and the backend will need to fix that. 
+	       */
+	      dev->does_color_shift = 1;
+	    }
+	  else
+	    {
+	      dev->does_color_shift = 0;
+	    }
+	  break;
+	}
+    }
+
+  DBG (DBG_info, "get_filled_data_length: to read = %ld\n", (long) *to_read);
+
+  DBG (DBG_proc, "get_filled_data_length: exit, status=%d\n", status);
+
+  return (status);
+}
+
+/* Start a scan. */
+static SANE_Status
+teco_scan (Teco_Scanner * dev)
+{
+  CDB cdb;
+  SANE_Status status;
+
+  DBG (DBG_proc, "teco_scan: enter\n");
+
+  MKSCSI_SCAN (cdb);
+
+  status = sanei_scsi_cmd2 (dev->sfd, cdb.data, cdb.len, NULL, 0, NULL, NULL);
+
+  DBG (DBG_proc, "teco_scan: exit, status=%d\n", status);
+
+  return status;
+}
+
+/* Do some vendor specific stuff. */
+static SANE_Status
+teco_vendor_spec (Teco_Scanner * dev)
+{
+  CDB cdb;
+  SANE_Status status;
+  size_t size;
+
+  DBG (DBG_proc, "teco_vendor_spec: enter\n");
+
+  size = 0x7800;
+
+  cdb.data[0] = 0x09;
+  cdb.data[1] = 0;
+  cdb.data[2] = 0;
+  cdb.data[3] = (size >> 8) & 0xff;
+  cdb.data[4] = (size >> 0) & 0xff;
+  cdb.data[5] = 0;
+  cdb.len = 6;
+
+  status = sanei_scsi_cmd2 (dev->sfd, cdb.data, cdb.len,
+			    NULL, 0, dev->buffer, &size);
+
+  /*hexdump (DBG_info2, "calibration:", dev->buffer, size); */
+
+  cdb.data[0] = 0x0E;
+  cdb.data[1] = 0;
+  cdb.data[2] = 0;
+  cdb.data[3] = 0;
+  cdb.data[4] = 0;
+  cdb.data[5] = 0;
+  cdb.len = 6;
+
+  status = sanei_scsi_cmd2 (dev->sfd, cdb.data, cdb.len, NULL, 0, NULL, NULL);
+
+  return status;
+}
+
+/* Send the gamma */
+static SANE_Status
+teco_send_gamma (Teco_Scanner * dev)
+{
+  CDB cdb;
+  SANE_Status status;
+  struct
+  {
+    unsigned char gamma_R[GAMMA_LENGTH];
+    unsigned char gamma_G[GAMMA_LENGTH];	/* also gray */
+    unsigned char gamma_B[GAMMA_LENGTH];
+    unsigned char gamma_unused[GAMMA_LENGTH];
+  }
+  param;
+  size_t i;
+  size_t size;
+
+  DBG (DBG_proc, "teco_send_gamma: enter\n");
+
+  size = sizeof (param);
+  assert (size == 4 * GAMMA_LENGTH);
+  MKSCSI_SEND_10 (cdb, 0x03, 0x02, size);
+
+  if (dev->val[OPT_CUSTOM_GAMMA].w)
+    {
+      /* Use the custom gamma. */
+      if (dev->scan_mode == TECO_GRAYSCALE)
+	{
+	  /* Gray */
+	  for (i = 0; i < GAMMA_LENGTH; i++)
+	    {
+	      param.gamma_R[i] = 0;
+	      param.gamma_G[i] = dev->gamma_GRAY[i];
+	      param.gamma_B[i] = 0;
+	      param.gamma_unused[i] = 0;
+	    }
+	}
+      else
+	{
+	  /* Color */
+	  for (i = 0; i < GAMMA_LENGTH; i++)
+	    {
+	      param.gamma_R[i] = dev->gamma_R[i];
+	      param.gamma_G[i] = dev->gamma_G[i];
+	      param.gamma_B[i] = dev->gamma_B[i];
+	      param.gamma_unused[i] = 0;
+	    }
+	}
+    }
+  else
+    {
+      for (i = 0; i < GAMMA_LENGTH; i++)
+	{
+	  param.gamma_R[i] = i / 4;
+	  param.gamma_G[i] = i / 4;
+	  param.gamma_B[i] = i / 4;
+	  param.gamma_unused[i] = 0;
+	}
+    }
+
+  hexdump (DBG_info2, "teco_send_gamma:", cdb.data, cdb.len);
+
+  status = sanei_scsi_cmd2 (dev->sfd, cdb.data, cdb.len,
+			    &param, size, NULL, NULL);
+
+  DBG (DBG_proc, "teco_send_gamma: exit, status=%d\n", status);
+
+  return (status);
+}
+
+/* Attach a scanner to this backend. */
+static SANE_Status
+attach_scanner (const char *devicename, Teco_Scanner ** devp)
+{
+  Teco_Scanner *dev;
+  SANE_Status status;
+  int sfd;
+
+  DBG (DBG_sane_proc, "attach_scanner: %s\n", devicename);
+
+  if (devp)
+    *devp = NULL;
+
+  /* Check if we know this device name. */
+  for (dev = first_dev; dev; dev = dev->next)
+    {
+      if (strcmp (dev->sane.name, devicename) == 0)
+	{
+	  if (devp)
+	    {
+	      *devp = dev;
+	    }
+	  DBG (DBG_info, "device is already known\n");
+	  return SANE_STATUS_GOOD;
+	}
+    }
+
+  /* Allocate a new scanner entry. */
+  dev = teco_init ();
+  if (dev == NULL)
+    {
+      DBG (DBG_error, "ERROR: not enough memory\n");
+      return SANE_STATUS_NO_MEM;
+    }
+
+  DBG (DBG_info, "attach_scanner: opening %s\n", devicename);
+
+  status = sanei_scsi_open (devicename, &sfd, teco_sense_handler, dev);
+  if (status != SANE_STATUS_GOOD)
+    {
+      DBG (DBG_error, "ERROR: attach_scanner: open failed (%s)\n",
+	   sane_strstatus (status));
+      teco_free (dev);
+      return SANE_STATUS_INVAL;
+    }
+
+  /* Fill some scanner specific values. */
+  dev->devicename = strdup (devicename);
+  dev->sfd = sfd;
+
+  /* Now, check that it is a scanner we support. */
+  if (teco_identify_scanner (dev) == SANE_FALSE)
+    {
+      DBG (DBG_error,
+	   "ERROR: attach_scanner: scanner-identification failed\n");
+      teco_free (dev);
+      return SANE_STATUS_INVAL;
+    }
+
+  teco_close (dev);
+
+  /* Set the default options for that scanner. */
+  dev->sane.name = dev->devicename;
+  dev->sane.vendor = dev->def->real_vendor;
+  dev->sane.model = dev->def->real_product;
+  dev->sane.type = "flatbed scanner";
+
+  /* Link the scanner with the others. */
+  dev->next = first_dev;
+  first_dev = dev;
+
+  if (devp)
+    {
+      *devp = dev;
+    }
+
+  num_devices++;
+
+  DBG (DBG_proc, "attach_scanner: exit\n");
+
+  return SANE_STATUS_GOOD;
+}
+
+static SANE_Status
+attach_one (const char *dev)
+{
+  attach_scanner (dev, NULL);
+  return SANE_STATUS_GOOD;
+}
+
+/* Reset the options for that scanner. */
+static void
+teco_init_options (Teco_Scanner * dev)
+{
+  int i;
+
+  /* Pre-initialize the options. */
+  memset (dev->opt, 0, sizeof (dev->opt));
+  memset (dev->val, 0, sizeof (dev->val));
+
+  for (i = 0; i < OPT_NUM_OPTIONS; ++i)
+    {
+      dev->opt[i].size = sizeof (SANE_Word);
+      dev->opt[i].cap = SANE_CAP_SOFT_SELECT | SANE_CAP_SOFT_DETECT;
+    }
+
+  /* Number of options. */
+  dev->opt[OPT_NUM_OPTS].name = "";
+  dev->opt[OPT_NUM_OPTS].title = SANE_TITLE_NUM_OPTIONS;
+  dev->opt[OPT_NUM_OPTS].desc = SANE_DESC_NUM_OPTIONS;
+  dev->opt[OPT_NUM_OPTS].type = SANE_TYPE_INT;
+  dev->opt[OPT_NUM_OPTS].cap = SANE_CAP_SOFT_DETECT;
+  dev->val[OPT_NUM_OPTS].w = OPT_NUM_OPTIONS;
+
+  /* Mode group */
+  dev->opt[OPT_MODE_GROUP].title = SANE_TITLE_SCAN_MODE;
+  dev->opt[OPT_MODE_GROUP].desc = "";	/* not valid for a group */
+  dev->opt[OPT_MODE_GROUP].type = SANE_TYPE_GROUP;
+  dev->opt[OPT_MODE_GROUP].cap = 0;
+  dev->opt[OPT_MODE_GROUP].size = 0;
+  dev->opt[OPT_MODE_GROUP].constraint_type = SANE_CONSTRAINT_NONE;
+
+  /* Scanner supported modes */
+  dev->opt[OPT_MODE].name = SANE_NAME_SCAN_MODE;
+  dev->opt[OPT_MODE].title = SANE_TITLE_SCAN_MODE;
+  dev->opt[OPT_MODE].desc = SANE_DESC_SCAN_MODE;
+  dev->opt[OPT_MODE].type = SANE_TYPE_STRING;
+  dev->opt[OPT_MODE].size = max_string_size (scan_mode_list);
+  dev->opt[OPT_MODE].constraint_type = SANE_CONSTRAINT_STRING_LIST;
+  dev->opt[OPT_MODE].constraint.string_list = scan_mode_list;
+  dev->val[OPT_MODE].s = (SANE_Char *) strdup ("");	/* will be set later */
+
+  /* X and Y resolution */
+  dev->opt[OPT_RESOLUTION].name = SANE_NAME_SCAN_RESOLUTION;
+  dev->opt[OPT_RESOLUTION].title = SANE_TITLE_SCAN_RESOLUTION;
+  dev->opt[OPT_RESOLUTION].desc = SANE_DESC_SCAN_RESOLUTION;
+  dev->opt[OPT_RESOLUTION].type = SANE_TYPE_INT;
+  dev->opt[OPT_RESOLUTION].unit = SANE_UNIT_DPI;
+  dev->opt[OPT_RESOLUTION].constraint_type = SANE_CONSTRAINT_RANGE;
+  dev->opt[OPT_RESOLUTION].constraint.range = &dev->def->res_range;
+  dev->val[OPT_RESOLUTION].w = 100;
+
+  /* Geometry group */
+  dev->opt[OPT_GEOMETRY_GROUP].title = SANE_I18N ("Geometry");
+  dev->opt[OPT_GEOMETRY_GROUP].desc = "";	/* not valid for a group */
+  dev->opt[OPT_GEOMETRY_GROUP].type = SANE_TYPE_GROUP;
+  dev->opt[OPT_GEOMETRY_GROUP].cap = 0;
+  dev->opt[OPT_GEOMETRY_GROUP].size = 0;
+  dev->opt[OPT_GEOMETRY_GROUP].constraint_type = SANE_CONSTRAINT_NONE;
+
+  /* Upper left X */
+  dev->opt[OPT_TL_X].name = SANE_NAME_SCAN_TL_X;
+  dev->opt[OPT_TL_X].title = SANE_TITLE_SCAN_TL_X;
+  dev->opt[OPT_TL_X].desc = SANE_DESC_SCAN_TL_X;
+  dev->opt[OPT_TL_X].type = SANE_TYPE_FIXED;
+  dev->opt[OPT_TL_X].unit = SANE_UNIT_MM;
+  dev->opt[OPT_TL_X].constraint_type = SANE_CONSTRAINT_RANGE;
+  dev->opt[OPT_TL_X].constraint.range = &x_range;
+  dev->val[OPT_TL_X].w = x_range.min;
+
+  /* Upper left Y */
+  dev->opt[OPT_TL_Y].name = SANE_NAME_SCAN_TL_Y;
+  dev->opt[OPT_TL_Y].title = SANE_TITLE_SCAN_TL_Y;
+  dev->opt[OPT_TL_Y].desc = SANE_DESC_SCAN_TL_Y;
+  dev->opt[OPT_TL_Y].type = SANE_TYPE_FIXED;
+  dev->opt[OPT_TL_Y].unit = SANE_UNIT_MM;
+  dev->opt[OPT_TL_Y].constraint_type = SANE_CONSTRAINT_RANGE;
+  dev->opt[OPT_TL_Y].constraint.range = &y_range;
+  dev->val[OPT_TL_Y].w = y_range.min;
+
+  /* Bottom-right x */
+  dev->opt[OPT_BR_X].name = SANE_NAME_SCAN_BR_X;
+  dev->opt[OPT_BR_X].title = SANE_TITLE_SCAN_BR_X;
+  dev->opt[OPT_BR_X].desc = SANE_DESC_SCAN_BR_X;
+  dev->opt[OPT_BR_X].type = SANE_TYPE_FIXED;
+  dev->opt[OPT_BR_X].unit = SANE_UNIT_MM;
+  dev->opt[OPT_BR_X].constraint_type = SANE_CONSTRAINT_RANGE;
+  dev->opt[OPT_BR_X].constraint.range = &x_range;
+  dev->val[OPT_BR_X].w = x_range.max;
+
+  /* Bottom-right y */
+  dev->opt[OPT_BR_Y].name = SANE_NAME_SCAN_BR_Y;
+  dev->opt[OPT_BR_Y].title = SANE_TITLE_SCAN_BR_Y;
+  dev->opt[OPT_BR_Y].desc = SANE_DESC_SCAN_BR_Y;
+  dev->opt[OPT_BR_Y].type = SANE_TYPE_FIXED;
+  dev->opt[OPT_BR_Y].unit = SANE_UNIT_MM;
+  dev->opt[OPT_BR_Y].constraint_type = SANE_CONSTRAINT_RANGE;
+  dev->opt[OPT_BR_Y].constraint.range = &y_range;
+  dev->val[OPT_BR_Y].w = y_range.max;
+
+  /* Enhancement group */
+  dev->opt[OPT_ENHANCEMENT_GROUP].title = SANE_I18N ("Enhancement");
+  dev->opt[OPT_ENHANCEMENT_GROUP].desc = "";	/* not valid for a group */
+  dev->opt[OPT_ENHANCEMENT_GROUP].type = SANE_TYPE_GROUP;
+  dev->opt[OPT_ENHANCEMENT_GROUP].cap = SANE_CAP_ADVANCED;
+  dev->opt[OPT_ENHANCEMENT_GROUP].size = 0;
+  dev->opt[OPT_ENHANCEMENT_GROUP].constraint_type = SANE_CONSTRAINT_NONE;
+
+  /* Halftone pattern */
+  dev->opt[OPT_DITHER].name = "dither";
+  dev->opt[OPT_DITHER].title = SANE_I18N ("Dither");
+  dev->opt[OPT_DITHER].desc = SANE_I18N ("Dither");
+  dev->opt[OPT_DITHER].type = SANE_TYPE_STRING;
+  dev->opt[OPT_DITHER].size = max_string_size (dither_list);
+  dev->opt[OPT_DITHER].cap |= SANE_CAP_INACTIVE;
+  dev->opt[OPT_DITHER].constraint_type = SANE_CONSTRAINT_STRING_LIST;
+  dev->opt[OPT_DITHER].constraint.string_list = dither_list;
+  dev->val[OPT_DITHER].s = strdup (dither_list[0]);
+
+  /* custom-gamma table */
+  dev->opt[OPT_CUSTOM_GAMMA].name = SANE_NAME_CUSTOM_GAMMA;
+  dev->opt[OPT_CUSTOM_GAMMA].title = SANE_TITLE_CUSTOM_GAMMA;
+  dev->opt[OPT_CUSTOM_GAMMA].desc = SANE_DESC_CUSTOM_GAMMA;
+  dev->opt[OPT_CUSTOM_GAMMA].type = SANE_TYPE_BOOL;
+  dev->opt[OPT_CUSTOM_GAMMA].cap |= SANE_CAP_INACTIVE;
+  dev->val[OPT_CUSTOM_GAMMA].w = SANE_FALSE;
+
+  /* red gamma vector */
+  dev->opt[OPT_GAMMA_VECTOR_R].name = SANE_NAME_GAMMA_VECTOR_R;
+  dev->opt[OPT_GAMMA_VECTOR_R].title = SANE_TITLE_GAMMA_VECTOR_R;
+  dev->opt[OPT_GAMMA_VECTOR_R].desc = SANE_DESC_GAMMA_VECTOR_R;
+  dev->opt[OPT_GAMMA_VECTOR_R].type = SANE_TYPE_INT;
+  dev->opt[OPT_GAMMA_VECTOR_R].cap |= SANE_CAP_INACTIVE;
+  dev->opt[OPT_GAMMA_VECTOR_R].unit = SANE_UNIT_NONE;
+  dev->opt[OPT_GAMMA_VECTOR_R].size = GAMMA_LENGTH * sizeof (SANE_Word);
+  dev->opt[OPT_GAMMA_VECTOR_R].constraint_type = SANE_CONSTRAINT_RANGE;
+  dev->opt[OPT_GAMMA_VECTOR_R].constraint.range = &gamma_range;
+  dev->val[OPT_GAMMA_VECTOR_R].wa = dev->gamma_R;
+
+  /* green and gamma vector */
+  dev->opt[OPT_GAMMA_VECTOR_G].name = SANE_NAME_GAMMA_VECTOR_G;
+  dev->opt[OPT_GAMMA_VECTOR_G].title = SANE_TITLE_GAMMA_VECTOR_G;
+  dev->opt[OPT_GAMMA_VECTOR_G].desc = SANE_DESC_GAMMA_VECTOR_G;
+  dev->opt[OPT_GAMMA_VECTOR_G].type = SANE_TYPE_INT;
+  dev->opt[OPT_GAMMA_VECTOR_G].cap |= SANE_CAP_INACTIVE;
+  dev->opt[OPT_GAMMA_VECTOR_G].unit = SANE_UNIT_NONE;
+  dev->opt[OPT_GAMMA_VECTOR_G].size = GAMMA_LENGTH * sizeof (SANE_Word);
+  dev->opt[OPT_GAMMA_VECTOR_G].constraint_type = SANE_CONSTRAINT_RANGE;
+  dev->opt[OPT_GAMMA_VECTOR_G].constraint.range = &gamma_range;
+  dev->val[OPT_GAMMA_VECTOR_G].wa = dev->gamma_G;
+
+  /* blue gamma vector */
+  dev->opt[OPT_GAMMA_VECTOR_B].name = SANE_NAME_GAMMA_VECTOR_B;
+  dev->opt[OPT_GAMMA_VECTOR_B].title = SANE_TITLE_GAMMA_VECTOR_B;
+  dev->opt[OPT_GAMMA_VECTOR_B].desc = SANE_DESC_GAMMA_VECTOR_B;
+  dev->opt[OPT_GAMMA_VECTOR_B].type = SANE_TYPE_INT;
+  dev->opt[OPT_GAMMA_VECTOR_B].cap |= SANE_CAP_INACTIVE;
+  dev->opt[OPT_GAMMA_VECTOR_B].unit = SANE_UNIT_NONE;
+  dev->opt[OPT_GAMMA_VECTOR_B].size = GAMMA_LENGTH * sizeof (SANE_Word);
+  dev->opt[OPT_GAMMA_VECTOR_B].constraint_type = SANE_CONSTRAINT_RANGE;
+  dev->opt[OPT_GAMMA_VECTOR_B].constraint.range = &gamma_range;
+  dev->val[OPT_GAMMA_VECTOR_B].wa = dev->gamma_B;
+
+  /* grayscale gamma vector */
+  dev->opt[OPT_GAMMA_VECTOR_GRAY].name = SANE_NAME_GAMMA_VECTOR;
+  dev->opt[OPT_GAMMA_VECTOR_GRAY].title = SANE_TITLE_GAMMA_VECTOR;
+  dev->opt[OPT_GAMMA_VECTOR_GRAY].desc = SANE_DESC_GAMMA_VECTOR;
+  dev->opt[OPT_GAMMA_VECTOR_GRAY].type = SANE_TYPE_INT;
+  dev->opt[OPT_GAMMA_VECTOR_GRAY].cap |= SANE_CAP_INACTIVE;
+  dev->opt[OPT_GAMMA_VECTOR_GRAY].unit = SANE_UNIT_NONE;
+  dev->opt[OPT_GAMMA_VECTOR_GRAY].size = GAMMA_LENGTH * sizeof (SANE_Word);
+  dev->opt[OPT_GAMMA_VECTOR_GRAY].constraint_type = SANE_CONSTRAINT_RANGE;
+  dev->opt[OPT_GAMMA_VECTOR_GRAY].constraint.range = &gamma_range;
+  dev->val[OPT_GAMMA_VECTOR_GRAY].wa = dev->gamma_GRAY;
+
+  /* Threshold */
+  dev->opt[OPT_THRESHOLD].name = SANE_NAME_THRESHOLD;
+  dev->opt[OPT_THRESHOLD].title = SANE_TITLE_THRESHOLD;
+  dev->opt[OPT_THRESHOLD].desc = SANE_DESC_THRESHOLD;
+  dev->opt[OPT_THRESHOLD].type = SANE_TYPE_INT;
+  dev->opt[OPT_THRESHOLD].unit = SANE_UNIT_NONE;
+  dev->opt[OPT_THRESHOLD].size = sizeof (SANE_Int);
+  dev->opt[OPT_THRESHOLD].cap |= SANE_CAP_INACTIVE;
+  dev->opt[OPT_THRESHOLD].constraint_type = SANE_CONSTRAINT_RANGE;
+  dev->opt[OPT_THRESHOLD].constraint.range = &threshold_range;
+  dev->val[OPT_THRESHOLD].w = 128;
+
+  /* preview */
+  dev->opt[OPT_PREVIEW].name = SANE_NAME_PREVIEW;
+  dev->opt[OPT_PREVIEW].title = SANE_TITLE_PREVIEW;
+  dev->opt[OPT_PREVIEW].desc = SANE_DESC_PREVIEW;
+  dev->opt[OPT_PREVIEW].type = SANE_TYPE_BOOL;
+  dev->opt[OPT_PREVIEW].cap = SANE_CAP_SOFT_DETECT | SANE_CAP_SOFT_SELECT;
+  dev->val[OPT_PREVIEW].w = SANE_FALSE;
+
+  /* Lastly, set the default scan mode. This might change some
+   * values previously set here. */
+  sane_control_option (dev, OPT_MODE, SANE_ACTION_SET_VALUE,
+		       (SANE_String_Const *) scan_mode_list[0], NULL);
+}
+
+/* 
+ * Wait until the scanner is ready.
+ */
+static SANE_Status
+teco_wait_scanner (Teco_Scanner * dev)
+{
+  SANE_Status status;
+  int timeout;
+  CDB cdb;
+
+  DBG (DBG_proc, "teco_wait_scanner: enter\n");
+
+  MKSCSI_TEST_UNIT_READY (cdb);
+
+  /* Set the timeout to 60 seconds. */
+  timeout = 60;
+
+  while (timeout > 0)
+    {
+
+      /* test unit ready */
+      status = sanei_scsi_cmd2 (dev->sfd, cdb.data, cdb.len,
+				NULL, 0, NULL, NULL);
+
+      if (status == SANE_STATUS_GOOD)
+	{
+	  return SANE_STATUS_GOOD;
+	}
+
+      sleep (1);
+    };
+
+  DBG (DBG_proc, "teco_wait_scanner: scanner not ready\n");
+  return (SANE_STATUS_IO_ERROR);
+}
+
+/* 
+ * Get the sense
+ */
+static SANE_Status
+teco_query_sense (Teco_Scanner * dev)
+{
+  SANE_Status status;
+  unsigned char buf[255];
+  CDB cdb;
+  size_t size;
+
+  DBG (DBG_proc, "teco_wait_scanner: enter\n");
+
+  size = sizeof (buf);
+  MKSCSI_REQUEST_SENSE (cdb, size);
+
+  status = sanei_scsi_cmd2 (dev->sfd, cdb.data, cdb.len, NULL, 0, buf, &size);
+
+  hexdump (DBG_info2, "sense", buf, size);
+
+  DBG (DBG_error, "teco_query_sense: return (%s)\n", sane_strstatus (status));
+  return (status);
+}
+
+/* 
+ * Adjust the rasters. This function is used during a color scan,
+ * because the scanner does not present a format sane can interpret
+ * directly.
+ *
+ * The scanner sends the colors by rasters (B then G then R), whereas
+ * sane is waiting for a group of 3 bytes per color. To make things
+ * funnier, the rasters are shifted. The format of those raster is: 
+ *   BGR...BGR
+ *
+ * For a proper scan, the first 2 R and 1 G, and the last 1 G and 2 B
+ * must be ignored. (TODO)
+ * 
+ * So this function reorders all that mess. It gets the input from
+ * dev->buffer and write the output in dev->image. size_in the the
+ * length of the valid data in dev->buffer.  */
+
+/* 0=red, 1=green, 2=blue */
+
+#define COLOR_0 2
+#define COLOR_1 1
+#define COLOR_2 0
+#define line_shift ( - dev->color_shift)
+
+static void
+teco_adjust_raster (Teco_Scanner * dev, size_t size_in)
+{
+  int nb_rasters;		/* number of rasters in dev->buffer */
+
+  int raster;			/* current raster number in buffer */
+  int line;			/* line number for that raster */
+  int color = -1;			/* color for that raster */
+  size_t offset;
+
+  DBG (DBG_proc, "teco_adjust_raster: enter\n");
+
+  assert (dev->scan_mode == TECO_COLOR);
+  assert ((size_in % dev->bytes_per_raster) == 0);
+
+  if (size_in == 0)
+    {
+      return;
+    }
+
+  /* 
+   * The color coding is one line for each color (in the RGB order).
+   * Recombine that stuff to create a RGB value for each pixel.
+   */
+
+  nb_rasters = size_in / dev->raster_size;
+
+  for (raster = 0; raster < nb_rasters; raster++)
+    {
+
+      /* 
+       * Find the color to which this raster belongs to.
+       */
+      line = 0;
+      if (dev->raster_num < dev->color_shift)
+	{
+	  color = COLOR_0;
+	  line = dev->raster_num;
+	}
+      else if (dev->raster_num < (3 * dev->color_shift))
+	{
+
+	  if ((dev->raster_num - line_shift) % 2)
+	    {
+	      color = COLOR_1;
+	      line = (dev->raster_num + line_shift) / 2;
+	    }
+	  else
+	    {
+	      color = COLOR_0;
+	      line = (dev->raster_num - line_shift) / 2;
+	    }
+	}
+      else if (dev->raster_num >= dev->raster_real - dev->color_shift)
+	{
+	  color = COLOR_2;
+	  line = dev->line;
+	}
+      else if (dev->raster_num >= dev->raster_real - 3 * dev->color_shift)
+	{
+	  if ((dev->raster_real - dev->raster_num - line_shift) % 2)
+	    {
+	      color = COLOR_2;
+	      line = dev->line;
+	    }
+	  else
+	    {
+	      color = COLOR_1;
+	      line = dev->line - line_shift;
+	    }
+	}
+      else
+	{
+	  switch ((dev->raster_num - 3 * line_shift) % 3)
+	    {
+	    case 0:
+	      color = COLOR_0;
+	      line = (dev->raster_num - 3 * line_shift) / 3;
+	      break;
+	    case 1:
+	      color = COLOR_1;
+	      line = dev->raster_num / 3;
+	      break;
+	    case 2:
+	      color = COLOR_2;
+	      line = (dev->raster_num + 3 * line_shift) / 3;
+	      break;
+	    }
+	}
+
+      /* Adjust the line number relative to the image. */
+      line -= dev->line;
+
+      offset = dev->image_end + line * dev->params.bytes_per_line;
+
+      assert (offset <= (dev->image_size - dev->params.bytes_per_line));
+
+      /* Copy the raster to the temporary image. */
+      {
+	int i;
+	unsigned char *src = dev->buffer + raster * dev->raster_size;
+	unsigned char *dest = dev->image + offset + color;
+
+	for (i = 0; i < dev->raster_size; i++)
+	  {
+	    *dest = *src;
+	    src++;
+	    dest += 3;
+	  }
+
+	assert (dest <= (dev->image + dev->image_size + 2));
+
+      }
+
+      DBG (DBG_info, "raster=%d, line=%d, color=%d\n", dev->raster_num,
+	   dev->line + line, color);
+
+      if (color == COLOR_2)
+	{
+	  /* This raster completes a new line */
+	  dev->line++;
+	  dev->image_end += dev->params.bytes_per_line;
+	}
+
+      dev->raster_num++;
+    }
+
+  DBG (DBG_proc, "teco_adjust_raster: exit\n");
+}
+
+/* Read the image from the scanner and fill the temporary buffer with it. */
+static SANE_Status
+teco_fill_image (Teco_Scanner * dev)
+{
+  SANE_Status status;
+  size_t size;
+  CDB cdb;
+  unsigned char *image;
+
+  DBG (DBG_proc, "teco_fill_image: enter\n");
+
+  assert (dev->image_begin == dev->image_end);
+  assert (dev->real_bytes_left > 0);
+
+  /* Copy the complete lines, plus the incompletes
+   * ones. We don't keep the real end of data used
+   * in image, so we copy the biggest possible. 
+   */
+  if (dev->scan_mode == TECO_COLOR)
+    {
+      memmove (dev->image, dev->image + dev->image_begin, dev->raster_ahead);
+    }
+
+  dev->image_begin = 0;
+  dev->image_end = 0;
+
+  while (dev->real_bytes_left)
+    {
+
+      /* todo: teco2 too */
+      /* Check that we can at least one line. */
+      if (dev->raster_ahead + dev->image_end + dev->params.bytes_per_line >
+	  dev->image_size)
+	{
+	  /* Probably reached the end of the buffer. 
+	   * Check, just in case. */
+	  assert (dev->image_end != 0);
+	  return (SANE_STATUS_GOOD);
+	}
+
+      /* 
+       * Try to read the maximum number of bytes.
+       */
+      size = 0;
+      while (size == 0)
+	{
+	  status = get_filled_data_length (dev, &size);
+	  if (status)
+	    return (status);
+	  if (size == 0)
+	    usleep (100000);	/* sleep 1/10th of second */
+	}
+
+      if (size > dev->real_bytes_left)
+	size = dev->real_bytes_left;
+      if (size > dev->image_size - dev->raster_ahead - dev->image_end)
+	size = dev->image_size - dev->raster_ahead - dev->image_end;
+      if (size > dev->buffer_size)
+	{
+	  size = dev->buffer_size;
+	}
+
+      /* Always read a multiple of a raster. */
+      size = size - (size % dev->bytes_per_raster);
+
+      if (size == 0)
+	{
+	  /* Probably reached the end of the buffer. 
+	   * Check, just in case. */
+	  assert (dev->image_end != 0);
+	  return (SANE_STATUS_GOOD);
+	}
+
+      DBG (DBG_info, "teco_fill_image: to read   = %ld bytes (bpl=%d)\n",
+	   (long) size, dev->params.bytes_per_line);
+
+      MKSCSI_READ_10 (cdb, 0, 0, size);
+
+      hexdump (DBG_info2, "teco_fill_image: READ_10 CDB", cdb.data, 10);
+      DBG (DBG_info, "  image_end=%lu\n", (u_long) dev->image_end);
+
+      if (dev->scan_mode == TECO_COLOR && dev->does_color_shift)
+	{
+	  image = dev->buffer;
+	}
+      else
+	{
+	  image = dev->image + dev->image_end;
+	}
+
+      status = sanei_scsi_cmd2 (dev->sfd, cdb.data, cdb.len,
+				NULL, 0, image, &size);
+
+      if (status != SANE_STATUS_GOOD)
+	{
+	  DBG (DBG_error, "teco_fill_image: cannot read from the scanner\n");
+	  return status;
+	}
+
+      /* The size this scanner returns is always a multiple of a
+       * raster size. */
+      assert ((size % dev->bytes_per_raster) == 0);
+
+      DBG (DBG_info, "teco_fill_image: real bytes left = %ld\n",
+	   (long) dev->real_bytes_left);
+
+      if (dev->scan_mode == TECO_COLOR && dev->does_color_shift)
+	{
+	  teco_adjust_raster (dev, size);
+	}
+      else
+	{
+	  /* Already in dev->image. */
+	  dev->image_end += size;
+	}
+
+      dev->real_bytes_left -= size;
+    }
+
+  return (SANE_STATUS_GOOD);	/* unreachable */
+}
+
+/* Copy from the raw buffer to the buffer given by the backend. 
+ *
+ * len in input is the maximum length available in buf, and, in
+ * output, is the length written into buf.
+ */
+static void
+teco_copy_raw_to_frontend (Teco_Scanner * dev, SANE_Byte * buf, size_t * len)
+{
+  size_t size;
+
+  size = dev->image_end - dev->image_begin;
+  if (size > *len)
+    {
+      size = *len;
+    }
+  *len = size;
+
+  switch (dev->scan_mode)
+    {
+    case TECO_BW:
+      {
+	/* For Black & White, the bits in every bytes are mirrored.
+	 * for instance 11010001 is coded as 10001011 */
+
+	unsigned char *src = dev->image + dev->image_begin;
+	size_t i;
+	unsigned char s;
+	unsigned char d;
+
+	for (i = 0; i < size; i++)
+	  {
+	    s = *src ^ 0xff;
+	    d = 0;
+	    if (s & 0x01)
+	      d |= 0x80;
+	    if (s & 0x02)
+	      d |= 0x40;
+	    if (s & 0x04)
+	      d |= 0x20;
+	    if (s & 0x08)
+	      d |= 0x10;
+	    if (s & 0x10)
+	      d |= 0x08;
+	    if (s & 0x20)
+	      d |= 0x04;
+	    if (s & 0x40)
+	      d |= 0x02;
+	    if (s & 0x80)
+	      d |= 0x01;
+	    *buf = d;
+	    src++;
+	    buf++;
+	  }
+      }
+      break;
+
+    case TECO_GRAYSCALE:
+    case TECO_COLOR:
+      memcpy (buf, dev->image + dev->image_begin, size);
+      break;
+    }
+
+  dev->image_begin += size;
+}
+
+/* Stop a scan. */
+static SANE_Status
+do_cancel (Teco_Scanner * dev)
+{
+  DBG (DBG_sane_proc, "do_cancel enter\n");
+
+  if (dev->scanning == SANE_TRUE)
+    {
+      teco_reset_window (dev);
+      teco_close (dev);
+    }
+
+  dev->scanning = SANE_FALSE;
+
+  DBG (DBG_sane_proc, "do_cancel exit\n");
+
+  return SANE_STATUS_CANCELLED;
+}
+
+/*--------------------------------------------------------------------------*/
+
+/* Sane entry points */
+
+SANE_Status
+sane_init (SANE_Int * version_code, SANE_Auth_Callback __sane_unused__ authorize)
+{
+  FILE *fp;
+  char dev_name[PATH_MAX];
+  size_t len;
+
+  DBG_INIT ();
+
+  DBG (DBG_sane_init, "sane_init\n");
+
+  DBG (DBG_error, "This is sane-teco3 version %d.%d-%d\n", SANE_CURRENT_MAJOR,
+       V_MINOR, BUILD);
+  DBG (DBG_error, "(C) 2002 by Frank Zago\n");
+
+  if (version_code)
+    {
+      *version_code = SANE_VERSION_CODE (SANE_CURRENT_MAJOR, V_MINOR, BUILD);
+    }
+
+  fp = sanei_config_open (TECO_CONFIG_FILE);
+  if (!fp)
+    {
+      /* default to /dev/scanner instead of insisting on config file */
+      attach_scanner ("/dev/scanner", 0);
+      return SANE_STATUS_GOOD;
+    }
+
+  while (sanei_config_read (dev_name, sizeof (dev_name), fp))
+    {
+      if (dev_name[0] == '#')	/* ignore line comments */
+	continue;
+      len = strlen (dev_name);
+
+      if (!len)
+	continue;		/* ignore empty lines */
+
+      sanei_config_attach_matching_devices (dev_name, attach_one);
+    }
+
+  fclose (fp);
+
+  DBG (DBG_proc, "sane_init: leave\n");
+
+  return SANE_STATUS_GOOD;
+}
+
+SANE_Status
+sane_get_devices (const SANE_Device *** device_list, SANE_Bool __sane_unused__ local_only)
+{
+  Teco_Scanner *dev;
+  int i;
+
+  DBG (DBG_proc, "sane_get_devices: enter\n");
+
+  if (devlist)
+    free (devlist);
+
+  devlist = malloc ((num_devices + 1) * sizeof (devlist[0]));
+  if (!devlist)
+    return SANE_STATUS_NO_MEM;
+
+  i = 0;
+  for (dev = first_dev; i < num_devices; dev = dev->next)
+    devlist[i++] = &dev->sane;
+  devlist[i++] = 0;
+
+  *device_list = devlist;
+
+  DBG (DBG_proc, "sane_get_devices: exit\n");
+
+  return SANE_STATUS_GOOD;
+}
+
+SANE_Status
+sane_open (SANE_String_Const devicename, SANE_Handle * handle)
+{
+  Teco_Scanner *dev;
+  SANE_Status status;
+  int i;
+
+  DBG (DBG_proc, "sane_open: enter\n");
+
+  /* search for devicename */
+  if (devicename[0])
+    {
+      DBG (DBG_info, "sane_open: devicename=%s\n", devicename);
+
+      for (dev = first_dev; dev; dev = dev->next)
+	{
+	  if (strcmp (dev->sane.name, devicename) == 0)
+	    {
+	      break;
+	    }
+	}
+
+      if (!dev)
+	{
+	  status = attach_scanner (devicename, &dev);
+	  if (status != SANE_STATUS_GOOD)
+	    {
+	      return status;
+	    }
+	}
+    }
+  else
+    {
+      DBG (DBG_sane_info, "sane_open: no devicename, opening first device\n");
+      dev = first_dev;		/* empty devicename -> use first device */
+    }
+
+  if (!dev)
+    {
+      DBG (DBG_error, "No scanner found\n");
+
+      return SANE_STATUS_INVAL;
+    }
+
+  teco_init_options (dev);
+
+  /* Initialize the gamma table. */
+  for (i = 0; i < GAMMA_LENGTH; i++)
+    {
+      dev->gamma_R[i] = i / 4;
+      dev->gamma_G[i] = i / 4;
+      dev->gamma_B[i] = i / 4;
+      dev->gamma_GRAY[i] = i / 4;
+    }
+
+  *handle = dev;
+
+  DBG (DBG_proc, "sane_open: exit\n");
+
+  return SANE_STATUS_GOOD;
+}
+
+const SANE_Option_Descriptor *
+sane_get_option_descriptor (SANE_Handle handle, SANE_Int option)
+{
+  Teco_Scanner *dev = handle;
+
+  DBG (DBG_proc, "sane_get_option_descriptor: enter, option %d\n", option);
+
+  if ((unsigned) option >= OPT_NUM_OPTIONS)
+    {
+      return NULL;
+    }
+
+  DBG (DBG_proc, "sane_get_option_descriptor: exit\n");
+
+  return dev->opt + option;
+}
+
+SANE_Status
+sane_control_option (SANE_Handle handle, SANE_Int option,
+		     SANE_Action action, void *val, SANE_Int * info)
+{
+  Teco_Scanner *dev = handle;
+  SANE_Status status;
+  SANE_Word cap;
+  SANE_String_Const name;
+
+  DBG (DBG_proc, "sane_control_option: enter, option %d, action %d\n",
+       option, action);
+
+  if (info)
+    {
+      *info = 0;
+    }
+
+  if (dev->scanning)
+    {
+      return SANE_STATUS_DEVICE_BUSY;
+    }
+
+  if (option < 0 || option >= OPT_NUM_OPTIONS)
+    {
+      return SANE_STATUS_INVAL;
+    }
+
+  cap = dev->opt[option].cap;
+  if (!SANE_OPTION_IS_ACTIVE (cap))
+    {
+      return SANE_STATUS_INVAL;
+    }
+
+  name = dev->opt[option].name;
+  if (!name)
+    {
+      name = "(no name)";
+    }
+  if (action == SANE_ACTION_GET_VALUE)
+    {
+
+      switch (option)
+	{
+	  /* word options */
+	case OPT_NUM_OPTS:
+	case OPT_RESOLUTION:
+	case OPT_TL_Y:
+	case OPT_BR_Y:
+	case OPT_TL_X:
+	case OPT_BR_X:
+	case OPT_CUSTOM_GAMMA:
+	case OPT_THRESHOLD:
+	case OPT_PREVIEW:
+	  *(SANE_Word *) val = dev->val[option].w;
+	  return SANE_STATUS_GOOD;
+
+	  /* string options */
+	case OPT_MODE:
+	case OPT_DITHER:
+	  strcpy (val, dev->val[option].s);
+	  return SANE_STATUS_GOOD;
+
+	  /* Gamma */
+	case OPT_GAMMA_VECTOR_R:
+	case OPT_GAMMA_VECTOR_G:
+	case OPT_GAMMA_VECTOR_B:
+	case OPT_GAMMA_VECTOR_GRAY:
+	  memcpy (val, dev->val[option].wa, dev->opt[option].size);
+	  return SANE_STATUS_GOOD;
+
+	default:
+	  return SANE_STATUS_INVAL;
+	}
+    }
+  else if (action == SANE_ACTION_SET_VALUE)
+    {
+
+      if (!SANE_OPTION_IS_SETTABLE (cap))
+	{
+	  DBG (DBG_error, "could not set option, not settable\n");
+	  return SANE_STATUS_INVAL;
+	}
+
+      status = sanei_constrain_value (dev->opt + option, val, info);
+      if (status != SANE_STATUS_GOOD)
+	{
+	  DBG (DBG_error, "could not set option, invalid value\n");
+	  return status;
+	}
+
+      switch (option)
+	{
+
+	  /* Numeric side-effect options */
+	case OPT_TL_Y:
+	case OPT_BR_Y:
+	case OPT_TL_X:
+	case OPT_BR_X:
+	case OPT_THRESHOLD:
+	case OPT_RESOLUTION:
+	  if (info)
+	    {
+	      *info |= SANE_INFO_RELOAD_PARAMS;
+	    }
+	  dev->val[option].w = *(SANE_Word *) val;
+	  return SANE_STATUS_GOOD;
+
+	  /* Numeric side-effect free options */
+	case OPT_PREVIEW:
+	  dev->val[option].w = *(SANE_Word *) val;
+	  return SANE_STATUS_GOOD;
+
+	  /* String side-effect free options */
+	case OPT_DITHER:
+	  free (dev->val[option].s);
+	  dev->val[option].s = (SANE_String) strdup (val);
+	  return SANE_STATUS_GOOD;
+
+	  /* String side-effect options */
+	case OPT_MODE:
+	  if (strcmp (dev->val[option].s, val) == 0)
+	    return SANE_STATUS_GOOD;
+
+	  free (dev->val[OPT_MODE].s);
+	  dev->val[OPT_MODE].s = (SANE_Char *) strdup (val);
+
+	  dev->opt[OPT_DITHER].cap |= SANE_CAP_INACTIVE;
+	  dev->opt[OPT_CUSTOM_GAMMA].cap |= SANE_CAP_INACTIVE;
+	  dev->opt[OPT_GAMMA_VECTOR_R].cap |= SANE_CAP_INACTIVE;
+	  dev->opt[OPT_GAMMA_VECTOR_G].cap |= SANE_CAP_INACTIVE;
+	  dev->opt[OPT_GAMMA_VECTOR_B].cap |= SANE_CAP_INACTIVE;
+	  dev->opt[OPT_GAMMA_VECTOR_GRAY].cap |= SANE_CAP_INACTIVE;
+	  dev->opt[OPT_THRESHOLD].cap |= SANE_CAP_INACTIVE;
+
+	  if (strcmp (dev->val[OPT_MODE].s, BLACK_WHITE_STR) == 0)
+	    {
+	      dev->depth = 8;
+	      dev->scan_mode = TECO_BW;
+	      dev->opt[OPT_DITHER].cap &= ~SANE_CAP_INACTIVE;
+	      dev->opt[OPT_THRESHOLD].cap &= ~SANE_CAP_INACTIVE;
+	    }
+	  else if (strcmp (dev->val[OPT_MODE].s, GRAY_STR) == 0)
+	    {
+	      dev->scan_mode = TECO_GRAYSCALE;
+	      dev->opt[OPT_CUSTOM_GAMMA].cap &= ~SANE_CAP_INACTIVE;
+	      if (dev->val[OPT_CUSTOM_GAMMA].w)
+		{
+		  dev->opt[OPT_GAMMA_VECTOR_GRAY].cap &= ~SANE_CAP_INACTIVE;
+		}
+	      dev->depth = 8;
+	    }
+	  else if (strcmp (dev->val[OPT_MODE].s, COLOR_STR) == 0)
+	    {
+	      dev->scan_mode = TECO_COLOR;
+	      dev->opt[OPT_CUSTOM_GAMMA].cap &= ~SANE_CAP_INACTIVE;
+	      if (dev->val[OPT_CUSTOM_GAMMA].w)
+		{
+		  dev->opt[OPT_GAMMA_VECTOR_R].cap &= ~SANE_CAP_INACTIVE;
+		  dev->opt[OPT_GAMMA_VECTOR_G].cap &= ~SANE_CAP_INACTIVE;
+		  dev->opt[OPT_GAMMA_VECTOR_B].cap &= ~SANE_CAP_INACTIVE;
+		}
+	      dev->depth = 8;
+	    }
+
+	  if (info)
+	    {
+	      *info |= SANE_INFO_RELOAD_OPTIONS | SANE_INFO_RELOAD_PARAMS;
+	    }
+	  return SANE_STATUS_GOOD;
+
+	case OPT_GAMMA_VECTOR_R:
+	case OPT_GAMMA_VECTOR_G:
+	case OPT_GAMMA_VECTOR_B:
+	case OPT_GAMMA_VECTOR_GRAY:
+	  memcpy (dev->val[option].wa, val, dev->opt[option].size);
+	  return SANE_STATUS_GOOD;
+
+	case OPT_CUSTOM_GAMMA:
+	  dev->val[OPT_CUSTOM_GAMMA].w = *(SANE_Word *) val;
+	  if (dev->val[OPT_CUSTOM_GAMMA].w)
+	    {
+	      /* use custom_gamma_table */
+	      if (dev->scan_mode == TECO_GRAYSCALE)
+		{
+		  dev->opt[OPT_GAMMA_VECTOR_GRAY].cap &= ~SANE_CAP_INACTIVE;
+		}
+	      else
+		{
+		  /* color mode */
+		  dev->opt[OPT_GAMMA_VECTOR_R].cap &= ~SANE_CAP_INACTIVE;
+		  dev->opt[OPT_GAMMA_VECTOR_G].cap &= ~SANE_CAP_INACTIVE;
+		  dev->opt[OPT_GAMMA_VECTOR_B].cap &= ~SANE_CAP_INACTIVE;
+		}
+	    }
+	  else
+	    {
+	      dev->opt[OPT_GAMMA_VECTOR_R].cap |= SANE_CAP_INACTIVE;
+	      dev->opt[OPT_GAMMA_VECTOR_G].cap |= SANE_CAP_INACTIVE;
+	      dev->opt[OPT_GAMMA_VECTOR_B].cap |= SANE_CAP_INACTIVE;
+	      dev->opt[OPT_GAMMA_VECTOR_GRAY].cap |= SANE_CAP_INACTIVE;
+	    }
+	  if (info)
+	    {
+	      *info |= SANE_INFO_RELOAD_OPTIONS;
+	    }
+	  return SANE_STATUS_GOOD;
+
+	default:
+	  return SANE_STATUS_INVAL;
+	}
+    }
+
+  DBG (DBG_proc, "sane_control_option: exit, bad\n");
+
+  return SANE_STATUS_UNSUPPORTED;
+}
+
+SANE_Status
+sane_get_parameters (SANE_Handle handle, SANE_Parameters * params)
+{
+  Teco_Scanner *dev = handle;
+
+  DBG (DBG_proc, "sane_get_parameters: enter\n");
+
+  if (!(dev->scanning))
+    {
+
+      /* Setup the parameters for the scan. These values will be re-used
+       * in the SET WINDOWS command. */
+      if (dev->val[OPT_PREVIEW].w == SANE_TRUE)
+	{
+	  dev->x_resolution = 50;
+	  dev->y_resolution = 50;
+	  dev->x_tl = 0;
+	  dev->y_tl = 0;
+	  dev->x_br = mmToIlu (SANE_UNFIX (x_range.max));
+	  dev->y_br = mmToIlu (SANE_UNFIX (y_range.max));
+	}
+      else
+	{
+	  dev->x_resolution = dev->val[OPT_RESOLUTION].w;
+	  dev->y_resolution = dev->val[OPT_RESOLUTION].w;
+	  if (dev->x_resolution > dev->def->x_resolution_max)
+	    {
+	      dev->x_resolution = dev->def->x_resolution_max;
+	    }
+
+	  dev->x_tl = mmToIlu (SANE_UNFIX (dev->val[OPT_TL_X].w));
+	  dev->y_tl = mmToIlu (SANE_UNFIX (dev->val[OPT_TL_Y].w));
+	  dev->x_br = mmToIlu (SANE_UNFIX (dev->val[OPT_BR_X].w));
+	  dev->y_br = mmToIlu (SANE_UNFIX (dev->val[OPT_BR_Y].w));
+	}
+
+      /* Check the corners are OK. */
+      if (dev->x_tl > dev->x_br)
+	{
+	  int s;
+	  s = dev->x_tl;
+	  dev->x_tl = dev->x_br;
+	  dev->x_br = s;
+	}
+      if (dev->y_tl > dev->y_br)
+	{
+	  int s;
+	  s = dev->y_tl;
+	  dev->y_tl = dev->y_br;
+	  dev->y_br = s;
+	}
+
+      dev->width = dev->x_br - dev->x_tl;
+      dev->length = dev->y_br - dev->y_tl;
+
+      /* Prepare the parameters for the caller. */
+      memset (&dev->params, 0, sizeof (SANE_Parameters));
+
+      dev->params.last_frame = SANE_TRUE;
+
+      switch (dev->scan_mode)
+	{
+	case TECO_BW:
+	  dev->params.format = SANE_FRAME_GRAY;
+	  dev->params.pixels_per_line =
+	    ((dev->width * dev->x_resolution) / 300) & ~0x7;
+	  dev->params.bytes_per_line = dev->params.pixels_per_line / 8;
+	  dev->params.depth = 1;
+	  dev->color_shift = 0;
+	  break;
+	case TECO_GRAYSCALE:
+	  dev->params.format = SANE_FRAME_GRAY;
+	  dev->params.pixels_per_line =
+	    ((dev->width * dev->x_resolution) / 300);
+	  dev->params.bytes_per_line = dev->params.pixels_per_line;
+	  dev->params.depth = 8;
+	  dev->color_shift = 0;
+	  break;
+	case TECO_COLOR:
+	  dev->params.format = SANE_FRAME_RGB;
+	  dev->params.pixels_per_line =
+	    ((dev->width * dev->x_resolution) / 300);
+	  dev->params.bytes_per_line = dev->params.pixels_per_line * 3;
+	  dev->params.depth = 8;
+
+	  /* If the scanner does not have enough memory, it will
+	   * send the raw rasters instead of returning a full
+	   * interleaved line. Unfortunatly this does not work well,
+	   * because I don't know how to compute the color
+	   * shifting. So here is the result of some trial and error
+	   * process. This is ignored if the scanner has a RAM
+	   * module.
+	   */
+	  dev->color_shift = dev->x_resolution / 75;
+
+	  break;
+	}
+
+      dev->params.lines = (dev->length * dev->y_resolution) / 300;
+    }
+
+  /* Return the current values. */
+  if (params)
+    {
+      *params = (dev->params);
+    }
+
+  DBG (DBG_proc, "sane_get_parameters: exit\n");
+
+  return SANE_STATUS_GOOD;
+}
+
+SANE_Status
+sane_start (SANE_Handle handle)
+{
+  Teco_Scanner *dev = handle;
+  SANE_Status status;
+  size_t size;
+
+  DBG (DBG_proc, "sane_start: enter\n");
+
+  if (!(dev->scanning))
+    {
+
+      /* Open again the scanner. */
+      if (sanei_scsi_open
+	  (dev->devicename, &(dev->sfd), teco_sense_handler, dev) != 0)
+	{
+	  DBG (DBG_error, "ERROR: sane_start: open failed\n");
+	  return SANE_STATUS_INVAL;
+	}
+
+      /* Set the correct parameters. */
+      sane_get_parameters (dev, NULL);
+
+      /* The scanner must be ready. */
+      status = teco_wait_scanner (dev);
+      if (status)
+	{
+	  teco_close (dev);
+	  return status;
+	}
+
+      teco_query_sense (dev);
+      teco_reset_window (dev);
+
+      status = teco_set_window (dev);
+      if (status)
+	{
+	  teco_close (dev);
+	  return status;
+	}
+
+      dev->real_bytes_left = 0;
+      status = get_filled_data_length (dev, &size);
+      if (status)
+	{
+	  teco_close (dev);
+	  return status;
+	}
+
+      /* Compute the length necessary in image. The first part will store
+       * the complete lines, and the rest is used to stored ahead
+       * rasters.
+       * Align image_size to a multiple of lines. (important)
+       */
+      dev->raster_ahead =
+	(2 * dev->color_shift + 1) * dev->params.bytes_per_line;
+      dev->image_size = dev->buffer_size + dev->raster_ahead;
+      dev->image_size =
+	dev->image_size - (dev->image_size % dev->params.bytes_per_line);
+      dev->image = malloc (dev->image_size);
+      if (dev->image == NULL)
+	{
+	  return SANE_STATUS_NO_MEM;
+	}
+
+      /* Rasters are meaningfull only in color mode. */
+      dev->raster_size = dev->params.pixels_per_line;
+      dev->raster_real = dev->params.lines * 3;
+      dev->raster_num = 0;
+      dev->line = 0;
+
+      teco_vendor_spec (dev);
+      if (status)
+	{
+	  teco_close (dev);
+	  return status;
+	}
+
+      status = teco_send_gamma (dev);
+      if (status)
+	{
+	  teco_close (dev);
+	  return status;
+	}
+
+      status = teco_set_window (dev);
+      if (status)
+	{
+	  teco_close (dev);
+	  return status;
+	}
+
+      status = teco_scan (dev);
+      if (status)
+	{
+	  teco_close (dev);
+	  return status;
+	}
+    }
+
+  dev->image_end = 0;
+  dev->image_begin = 0;
+
+  dev->bytes_left = dev->params.bytes_per_line * dev->params.lines;
+  dev->real_bytes_left = dev->params.bytes_per_line * dev->params.lines;
+
+  dev->scanning = SANE_TRUE;
+
+  DBG (DBG_proc, "sane_start: exit\n");
+
+  return SANE_STATUS_GOOD;
+}
+
+SANE_Status
+sane_read (SANE_Handle handle, SANE_Byte * buf, SANE_Int max_len,
+	   SANE_Int * len)
+{
+  SANE_Status status;
+  Teco_Scanner *dev = handle;
+  size_t size;
+  int buf_offset;		/* offset into buf */
+
+  DBG (DBG_proc, "sane_read: enter\n");
+
+  *len = 0;
+
+  if (!(dev->scanning))
+    {
+      /* OOPS, not scanning */
+      return do_cancel (dev);
+    }
+
+  if (dev->bytes_left <= 0)
+    {
+      return (SANE_STATUS_EOF);
+    }
+
+  buf_offset = 0;
+
+  do
+    {
+      if (dev->image_begin == dev->image_end)
+	{
+	  /* Fill image */
+	  status = teco_fill_image (dev);
+	  if (status != SANE_STATUS_GOOD)
+	    {
+	      return (status);
+	    }
+	}
+
+      /* Something must have been read */
+      if (dev->image_begin == dev->image_end)
+	{
+	  DBG (DBG_info, "sane_read: nothing read\n");
+	  return SANE_STATUS_IO_ERROR;
+	}
+
+      /* Copy the data to the frontend buffer. */
+      size = max_len - buf_offset;
+      if (size > dev->bytes_left)
+	{
+	  size = dev->bytes_left;
+	}
+      teco_copy_raw_to_frontend (dev, buf + buf_offset, &size);
+
+      buf_offset += size;
+
+      dev->bytes_left -= size;
+      *len += size;
+
+    }
+  while ((buf_offset != max_len) && dev->bytes_left);
+
+  DBG (DBG_info, "sane_read: leave, bytes_left=%ld\n",
+       (long) dev->bytes_left);
+
+  return SANE_STATUS_GOOD;
+}
+
+SANE_Status
+sane_set_io_mode (SANE_Handle __sane_unused__ handle, SANE_Bool __sane_unused__ non_blocking)
+{
+  SANE_Status status;
+  Teco_Scanner *dev = handle;
+
+  DBG (DBG_proc, "sane_set_io_mode: enter\n");
+
+  if (dev->scanning == SANE_FALSE)
+    {
+      return SANE_STATUS_INVAL;
+    }
+
+  if (non_blocking == SANE_FALSE)
+    {
+      status = SANE_STATUS_GOOD;
+    }
+  else
+    {
+      status = SANE_STATUS_UNSUPPORTED;
+    }
+
+  DBG (DBG_proc, "sane_set_io_mode: exit\n");
+
+  return status;
+}
+
+SANE_Status
+sane_get_select_fd (SANE_Handle __sane_unused__ handle, SANE_Int __sane_unused__ * fd)
+{
+  DBG (DBG_proc, "sane_get_select_fd: enter\n");
+
+  DBG (DBG_proc, "sane_get_select_fd: exit\n");
+
+  return SANE_STATUS_UNSUPPORTED;
+}
+
+void
+sane_cancel (SANE_Handle handle)
+{
+  Teco_Scanner *dev = handle;
+
+  DBG (DBG_proc, "sane_cancel: enter\n");
+
+  do_cancel (dev);
+
+  DBG (DBG_proc, "sane_cancel: exit\n");
+}
+
+void
+sane_close (SANE_Handle handle)
+{
+  Teco_Scanner *dev = handle;
+  Teco_Scanner *dev_tmp;
+
+  DBG (DBG_proc, "sane_close: enter\n");
+
+  do_cancel (dev);
+  teco_close (dev);
+
+  /* Unlink dev. */
+  if (first_dev == dev)
+    {
+      first_dev = dev->next;
+    }
+  else
+    {
+      dev_tmp = first_dev;
+      while (dev_tmp->next && dev_tmp->next != dev)
+	{
+	  dev_tmp = dev_tmp->next;
+	}
+      if (dev_tmp->next != NULL)
+	{
+	  dev_tmp->next = dev_tmp->next->next;
+	}
+    }
+
+  teco_free (dev);
+  num_devices--;
+
+  DBG (DBG_proc, "sane_close: exit\n");
+}
+
+void
+sane_exit (void)
+{
+  DBG (DBG_proc, "sane_exit: enter\n");
+
+  while (first_dev)
+    {
+      sane_close (first_dev);
+    }
+
+  if (devlist)
+    {
+      free (devlist);
+      devlist = NULL;
+    }
+
+  DBG (DBG_proc, "sane_exit: exit\n");
+}