Logo Search packages:      
Sourcecode: scanbuttond version File versions

snapscan.c

// snapscan.c: Snapscan device backend
// This file is part of scanbuttond.
// Copyleft )c( 2005-2006 by Bernhard Stiftner
// Thanks to J. Javier Maestro for sniffing the button codes ;-)
//
// 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., 675 Mass Ave, Cambridge, MA 02139, USA.

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <syslog.h>
#include "scanbuttond/scanbuttond.h"
#include "scanbuttond/libusbi.h"
#include "snapscan.h"

static char* backend_name = "Snapscan USB";

#define NUM_SUPPORTED_USB_DEVICES 3

static int supported_usb_devices[NUM_SUPPORTED_USB_DEVICES][3] = {
      { 0x04b8, 0x0121, 4 },  // Epson Perfection 2480
      { 0x04b8, 0x011f, 4 },  // Epson Perfection 1670
      { 0x04b8, 0x0122, 4 }   // Epson Perfection 3490
};

// TODO: check if this backend really works on the Epson 2580 too...
static char* usb_device_descriptions[NUM_SUPPORTED_USB_DEVICES][2] = {
         { "Epson", "Perfection 2480 / 2580" },
         { "Epson", "Perfection 1670" },
         { "Epson", "Perfection 3490" }
};


libusb_handle_t* libusb_handle;
scanner_t* snapscan_scanners = NULL;


// returns -1 if the scanner is unsupported, or the index of the
// corresponding vendor-product pair in the supported_usb_devices array.
int snapscan_match_libusb_scanner(libusb_device_t* device)
{
      int index;
      for (index = 0; index < NUM_SUPPORTED_USB_DEVICES; index++) {
            if (supported_usb_devices[index][0] == device->vendorID &&
                          supported_usb_devices[index][1] == device->productID) {
                  break;
            }
      }
      if (index >= NUM_SUPPORTED_USB_DEVICES) return -1;
      return index;
}


void snapscan_attach_libusb_scanner(libusb_device_t* device)
{
      const char* descriptor_prefix = "snapscan:libusb:";
      int index = snapscan_match_libusb_scanner(device);
      if (index < 0) return; // unsupported
      scanner_t* scanner = (scanner_t*)malloc(sizeof(scanner_t));
      scanner->vendor = usb_device_descriptions[index][0];
      scanner->product = usb_device_descriptions[index][1];
      scanner->connection = CONNECTION_LIBUSB;
      scanner->internal_dev_ptr = (void*)device;
      scanner->lastbutton = 0;
      scanner->sane_device = (char*)malloc(strlen(device->location) + 
            strlen(descriptor_prefix) + 1);
      strcpy(scanner->sane_device, descriptor_prefix);
      strcat(scanner->sane_device, device->location);
      scanner->num_buttons = supported_usb_devices[index][2];
      scanner->is_open = 0;
      scanner->next = snapscan_scanners;
      snapscan_scanners = scanner;
}


void snapscan_detach_scanners(void)
{
      scanner_t* next;
      while (snapscan_scanners != NULL) {
            next = snapscan_scanners->next;
            free(snapscan_scanners->sane_device);
            free(snapscan_scanners);
            snapscan_scanners = next;
      }
}


void snapscan_scan_devices(libusb_device_t* devices)
{
      int index;
      libusb_device_t* device = devices;
      while (device != NULL) {
            index = snapscan_match_libusb_scanner(device);
            if (index >= 0) 
                  snapscan_attach_libusb_scanner(device);
            device = device->next;
      }
}


int snapscan_init_libusb(void)
{
      libusb_device_t* devices;

      libusb_handle = libusb_init();
      devices = libusb_get_devices(libusb_handle);
      snapscan_scan_devices(devices);
      return 0;
}


const char* scanbtnd_get_backend_name(void)
{
      return backend_name;
}


int scanbtnd_init(void)
{
      snapscan_scanners = NULL;

      syslog(LOG_INFO, "snapscan-backend: init");
      return snapscan_init_libusb();
}


int scanbtnd_rescan(void)
{
      libusb_device_t* devices;

      snapscan_detach_scanners();
      snapscan_scanners = NULL;
      libusb_rescan(libusb_handle);
      devices = libusb_get_devices(libusb_handle);
      snapscan_scan_devices(devices);
      return 0;
}


const scanner_t* scanbtnd_get_supported_devices(void)
{
      return snapscan_scanners;
}


int scanbtnd_open(scanner_t* scanner)
{
      int result = -ENOSYS;
      if (scanner->is_open)
            return -EINVAL;
      switch (scanner->connection) {
            case CONNECTION_LIBUSB:
                  // if devices have been added/removed, return -ENODEV to
                  // make scanbuttond update its device list
                  if (libusb_get_changed_device_count() != 0)
                        return -ENODEV;
                  result = libusb_open((libusb_device_t*)scanner->internal_dev_ptr);
                  break;
      }
      if (result == 0)
            scanner->is_open = 1;
      return result;
}


int scanbtnd_close(scanner_t* scanner)
{
      int result = -ENOSYS;
      if (!scanner->is_open)
            return -EINVAL;
      switch (scanner->connection) {
            case CONNECTION_LIBUSB:
                  result = libusb_close((libusb_device_t*)scanner->internal_dev_ptr);
                  break;
      }
      if (result == 0)
            scanner->is_open = 0;
      return result;
}


int snapscan_read(scanner_t* scanner, void* buffer, int bytecount)
{
      switch (scanner->connection) {
            case CONNECTION_LIBUSB:
                  return libusb_read((libusb_device_t*)scanner->internal_dev_ptr, 
                        buffer, bytecount);
                  break;
      }
      return -1;
}


int snapscan_write(scanner_t* scanner, void* buffer, int bytecount)
{
      switch (scanner->connection) {
            case CONNECTION_LIBUSB:
                  return libusb_write((libusb_device_t*)scanner->internal_dev_ptr, 
                        buffer, bytecount);
                  break;
      }
      return -1;
}

void snapscan_flush(scanner_t* scanner)
{
      switch (scanner->connection) {
            case CONNECTION_LIBUSB:
                  libusb_flush((libusb_device_t*)scanner->internal_dev_ptr);
                  break;
      }
}



int scanbtnd_get_button(scanner_t* scanner)
{
      unsigned char bytes[255];
      int num_bytes;
      int button = 0;

      bytes[0] = 0x03;
      bytes[1] = 0x00;
      bytes[2] = 0x00;
      bytes[3] = 0x00;
      bytes[4] = 0x14;
      bytes[5] = 0x00;

      if (!scanner->is_open)
            return -EINVAL;

      num_bytes = snapscan_write(scanner, (void*)bytes, 6);
      if (num_bytes != 6) {
            snapscan_flush(scanner);
            return 0;
      }

      num_bytes = snapscan_read(scanner, (void*)bytes, 8);
      if (num_bytes != 8 || bytes[0] != 0xF9) {
            snapscan_flush(scanner);
            return 0;
      }

      num_bytes = snapscan_read(scanner, (void*)bytes, 20);
      if (num_bytes != 20 || bytes[0] != 0xF0) {
            snapscan_flush(scanner); 
            return 0;
      }
      if (bytes[2] == 0x06) {
            switch (bytes[18] & 0xF0) {
                  case 0x10: button = 1; break;
                  case 0x20: button = 2; break;
                  case 0x40: button = 3; break;
                  case 0x80: button = 4; break;
                  default: button = 0; break;
            }
      }

      num_bytes = snapscan_read(scanner, (void*)bytes, 8);
      if (num_bytes != 8 || bytes[0] != 0xFB) {
            snapscan_flush(scanner);
            return 0;
      }

      return button;
}


const char* scanbtnd_get_sane_device_descriptor(scanner_t* scanner)
{
      return scanner->sane_device;
}


int scanbtnd_exit(void)
{
      syslog(LOG_INFO, "snapscan-backend: exit");
      snapscan_detach_scanners();
      libusb_exit(libusb_handle);
      return 0;
}


Generated by  Doxygen 1.6.0   Back to index