Merge branch 'gr-fcd'

1 files changed, 1386 insertions, 0 deletions

diff --git a/gr-fcd/lib/hid/hid-libusb.c b/gr-fcd/lib/hid/hid-libusb.c
new file mode 100644
index 000000000..7069f50d0
--- /dev/null
+++ b/gr-fcd/lib/hid/hid-libusb.c
@@ -0,0 +1,1386 @@
+/*******************************************************
+ HIDAPI - Multi-Platform library for
+ communication with HID devices.
+
+ Alan Ott
+ Signal 11 Software
+
+ 8/22/2009
+ Linux Version - 6/2/2010
+ Libusb Version - 8/13/2010
+
+ Copyright 2009, All Rights Reserved.
+ 
+ At the discretion of the user of this library,
+ this software may be licensed under the terms of the
+ GNU Public License v3, a BSD-Style license, or the
+ original HIDAPI license as outlined in the LICENSE.txt,
+ LICENSE-gpl3.txt, LICENSE-bsd.txt, and LICENSE-orig.txt
+ files located at the root of the source distribution.
+ These files may also be found in the public source
+ code repository located at:
+        http://github.com/signal11/hidapi .
+********************************************************/
+
+#define _GNU_SOURCE // needed for wcsdup() before glibc 2.10
+
+/* C */
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <locale.h>
+#include <errno.h>
+
+/* Unix */
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <sys/utsname.h>
+#include <fcntl.h>
+#include <pthread.h>
+#include <wchar.h>
+
+/* GNU / LibUSB */
+#include "libusb.h"
+#include "iconv.h"
+
+#include "hidapi.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef DEBUG_PRINTF
+#define LOG(...) fprintf(stderr, __VA_ARGS__)
+#else
+#define LOG(...) do {} while (0)
+#endif
+
+
+/* Uncomment to enable the retrieval of Usage and Usage Page in
+hid_enumerate(). Warning, this is very invasive as it requires the detach
+and re-attach of the kernel driver. See comments inside hid_enumerate().
+Linux/libusb HIDAPI programs are encouraged to use the interface number
+instead to differentiate between interfaces on a composite HID device. */
+/*#define INVASIVE_GET_USAGE*/
+
+/* Linked List of input reports received from the device. */
+struct input_report {
+	uint8_t *data;
+	size_t len;
+	struct input_report *next;
+};
+
+
+struct hid_device_ {
+	/* Handle to the actual device. */
+	libusb_device_handle *device_handle;
+	
+	/* Endpoint information */
+	int input_endpoint;
+	int output_endpoint;
+	int input_ep_max_packet_size;
+
+	/* The interface number of the HID */	
+	int interface;
+	
+	/* Indexes of Strings */
+	int manufacturer_index;
+	int product_index;
+	int serial_index;
+	
+	/* Whether blocking reads are used */
+	int blocking; /* boolean */
+	
+	/* Read thread objects */
+	pthread_t thread;
+	pthread_mutex_t mutex; /* Protects input_reports */
+	pthread_cond_t condition;
+	pthread_barrier_t barrier; /* Ensures correct startup sequence */
+	int shutdown_thread;
+	struct libusb_transfer *transfer;
+
+	/* List of received input reports. */
+	struct input_report *input_reports;
+};
+
+static int initialized = 0;
+
+uint16_t get_usb_code_for_current_locale(void);
+static int return_data(hid_device *dev, unsigned char *data, size_t length);
+
+static hid_device *new_hid_device(void)
+{
+	hid_device *dev = calloc(1, sizeof(hid_device));
+	dev->device_handle = NULL;
+	dev->input_endpoint = 0;
+	dev->output_endpoint = 0;
+	dev->input_ep_max_packet_size = 0;
+	dev->interface = 0;
+	dev->manufacturer_index = 0;
+	dev->product_index = 0;
+	dev->serial_index = 0;
+	dev->blocking = 1;
+	dev->shutdown_thread = 0;
+	dev->transfer = NULL;
+	dev->input_reports = NULL;
+	
+	pthread_mutex_init(&dev->mutex, NULL);
+	pthread_cond_init(&dev->condition, NULL);
+	pthread_barrier_init(&dev->barrier, NULL, 2);
+	
+	return dev;
+}
+
+static void free_hid_device(hid_device *dev)
+{
+	/* Clean up the thread objects */
+	pthread_barrier_destroy(&dev->barrier);
+	pthread_cond_destroy(&dev->condition);
+	pthread_mutex_destroy(&dev->mutex);
+
+	/* Free the device itself */
+	free(dev);
+}
+
+#if 0
+//TODO: Implement this funciton on Linux.
+static void register_error(hid_device *device, const char *op)
+{
+
+}
+#endif
+
+#ifdef INVASIVE_GET_USAGE
+/* Get bytes from a HID Report Descriptor.
+   Only call with a num_bytes of 0, 1, 2, or 4. */
+static uint32_t get_bytes(uint8_t *rpt, size_t len, size_t num_bytes, size_t cur)
+{
+	/* Return if there aren't enough bytes. */
+	if (cur + num_bytes >= len)
+		return 0;
+
+	if (num_bytes == 0)
+		return 0;
+	else if (num_bytes == 1) {
+		return rpt[cur+1];
+	}
+	else if (num_bytes == 2) {
+		return (rpt[cur+2] * 256 + rpt[cur+1]);
+	}
+	else if (num_bytes == 4) {
+		return (rpt[cur+4] * 0x01000000 +
+		        rpt[cur+3] * 0x00010000 +
+		        rpt[cur+2] * 0x00000100 +
+		        rpt[cur+1] * 0x00000001);
+	}
+	else
+		return 0;
+}
+
+/* Retrieves the device's Usage Page and Usage from the report
+   descriptor. The algorithm is simple, as it just returns the first
+   Usage and Usage Page that it finds in the descriptor.
+   The return value is 0 on success and -1 on failure. */
+static int get_usage(uint8_t *report_descriptor, size_t size,
+                     unsigned short *usage_page, unsigned short *usage)
+{
+	int i = 0;
+	int size_code;
+	int data_len, key_size;
+	int usage_found = 0, usage_page_found = 0;
+	
+	while (i < size) {
+		int key = report_descriptor[i];
+		int key_cmd = key & 0xfc;
+
+		//printf("key: %02hhx\n", key);
+		
+		if ((key & 0xf0) == 0xf0) {
+			/* This is a Long Item. The next byte contains the
+			   length of the data section (value) for this key.
+			   See the HID specification, version 1.11, section
+			   6.2.2.3, titled "Long Items." */
+			if (i+1 < size)
+				data_len = report_descriptor[i+1];
+			else
+				data_len = 0; /* malformed report */
+			key_size = 3;
+		}
+		else {
+			/* This is a Short Item. The bottom two bits of the
+			   key contain the size code for the data section
+			   (value) for this key.  Refer to the HID
+			   specification, version 1.11, section 6.2.2.2,
+			   titled "Short Items." */
+			size_code = key & 0x3;
+			switch (size_code) {
+			case 0:
+			case 1:
+			case 2:
+				data_len = size_code;
+				break;
+			case 3:
+				data_len = 4;
+				break;
+			default:
+				/* Can't ever happen since size_code is & 0x3 */
+				data_len = 0;
+				break;
+			};
+			key_size = 1;
+		}
+		
+		if (key_cmd == 0x4) {
+			*usage_page  = get_bytes(report_descriptor, size, data_len, i);
+			usage_page_found = 1;
+			//printf("Usage Page: %x\n", (uint32_t)*usage_page);
+		}
+		if (key_cmd == 0x8) {
+			*usage = get_bytes(report_descriptor, size, data_len, i);
+			usage_found = 1;
+			//printf("Usage: %x\n", (uint32_t)*usage);
+		}
+
+		if (usage_page_found && usage_found)
+			return 0; /* success */
+		
+		/* Skip over this key and it's associated data */
+		i += data_len + key_size;
+	}
+	
+	return -1; /* failure */
+}
+#endif // INVASIVE_GET_USAGE
+
+
+/* Get the first language the device says it reports. This comes from
+   USB string #0. */
+static uint16_t get_first_language(libusb_device_handle *dev)
+{
+	uint16_t buf[32];
+	int len;
+	
+	/* Get the string from libusb. */
+	len = libusb_get_string_descriptor(dev,
+			0x0, /* String ID */
+			0x0, /* Language */
+			(unsigned char*)buf,
+			sizeof(buf));
+	if (len < 4)
+		return 0x0;
+	
+	return buf[1]; // First two bytes are len and descriptor type.
+}
+
+static int is_language_supported(libusb_device_handle *dev, uint16_t lang)
+{
+	uint16_t buf[32];
+	int len;
+	int i;
+	
+	/* Get the string from libusb. */
+	len = libusb_get_string_descriptor(dev,
+			0x0, /* String ID */
+			0x0, /* Language */
+			(unsigned char*)buf,
+			sizeof(buf));
+	if (len < 4)
+		return 0x0;
+	
+	
+	len /= 2; /* language IDs are two-bytes each. */
+	/* Start at index 1 because there are two bytes of protocol data. */
+	for (i = 1; i < len; i++) {
+		if (buf[i] == lang)
+			return 1;
+	}
+
+	return 0;
+}
+
+
+/* This function returns a newly allocated wide string containing the USB
+   device string numbered by the index. The returned string must be freed
+   by using free(). */
+static wchar_t *get_usb_string(libusb_device_handle *dev, uint8_t idx)
+{
+	char buf[512];
+	unsigned int len;
+	wchar_t *str = NULL;
+	wchar_t wbuf[256];
+
+	/* iconv variables */
+	iconv_t ic;
+	size_t inbytes;
+	size_t outbytes;
+	size_t res;
+	char *inptr;
+	char *outptr;
+
+	/* Determine which language to use. */
+	uint16_t lang;
+	lang = get_usb_code_for_current_locale();
+	if (!is_language_supported(dev, lang))
+		lang = get_first_language(dev);
+		
+	/* Get the string from libusb. */
+	len = libusb_get_string_descriptor(dev,
+			idx,
+			lang,
+			(unsigned char*)buf,
+			sizeof(buf));
+	if (len < 0)
+		return NULL;
+	
+	buf[sizeof(buf)-1] = '\0';
+	
+	if (len+1 < sizeof(buf))
+		buf[len+1] = '\0';
+	
+	/* Initialize iconv. */
+	ic = iconv_open("UTF-32", "UTF-16");
+	if (ic == (iconv_t)-1)
+		return NULL;
+	
+	/* Convert to UTF-32 (wchar_t on glibc systems).
+	   Skip the first character (2-bytes). */
+	inptr = buf+2;
+	inbytes = len-2;
+	outptr = (char*) wbuf;
+	outbytes = sizeof(wbuf);
+	res = iconv(ic, &inptr, &inbytes, &outptr, &outbytes);
+	if (res == (size_t)-1)
+		goto err;
+
+	/* Write the terminating NULL. */
+	wbuf[sizeof(wbuf)/sizeof(wbuf[0])-1] = 0x00000000;
+	if (outbytes >= sizeof(wbuf[0]))
+		*((wchar_t*)outptr) = 0x00000000;
+	
+	/* Allocate and copy the string. */
+	str = wcsdup(wbuf+1);
+
+err:
+	iconv_close(ic);
+	
+	return str;
+}
+
+static char *make_path(libusb_device *dev, int interface_number)
+{
+	char str[64];
+	snprintf(str, sizeof(str), "%04x:%04x:%02x",
+		libusb_get_bus_number(dev),
+		libusb_get_device_address(dev),
+		interface_number);
+	str[sizeof(str)-1] = '\0';
+	
+	return strdup(str);
+}
+
+
+int HID_API_EXPORT hid_init(void)
+{
+	if (!initialized) {
+		if (libusb_init(NULL))
+			return -1;
+		initialized = 1;
+	}
+
+	return 0;
+}
+
+int HID_API_EXPORT hid_exit(void)
+{
+	if (initialized) {
+		libusb_exit(NULL);
+		initialized = 0;
+	}
+
+	return 0;
+}
+
+struct hid_device_info  HID_API_EXPORT *hid_enumerate(unsigned short vendor_id, unsigned short product_id)
+{
+	libusb_device **devs;
+	libusb_device *dev;
+	libusb_device_handle *handle;
+	ssize_t num_devs;
+	int i = 0;
+	
+	struct hid_device_info *root = NULL; // return object
+	struct hid_device_info *cur_dev = NULL;
+	
+	setlocale(LC_ALL,"");
+	
+	if (!initialized)
+		hid_init();
+
+	num_devs = libusb_get_device_list(NULL, &devs);
+	if (num_devs < 0)
+		return NULL;
+	while ((dev = devs[i++]) != NULL) {
+		struct libusb_device_descriptor desc;
+		struct libusb_config_descriptor *conf_desc = NULL;
+		int j, k;
+		int interface_num = 0;
+
+		int res = libusb_get_device_descriptor(dev, &desc);
+		unsigned short dev_vid = desc.idVendor;
+		unsigned short dev_pid = desc.idProduct;
+		
+		/* HID's are defined at the interface level. */
+		if (desc.bDeviceClass != LIBUSB_CLASS_PER_INTERFACE)
+			continue;
+
+		res = libusb_get_active_config_descriptor(dev, &conf_desc);
+		if (res < 0)
+			libusb_get_config_descriptor(dev, 0, &conf_desc);
+		if (conf_desc) {
+			for (j = 0; j < conf_desc->bNumInterfaces; j++) {
+				const struct libusb_interface *intf = &conf_desc->interface[j];
+				for (k = 0; k < intf->num_altsetting; k++) {
+					const struct libusb_interface_descriptor *intf_desc;
+					intf_desc = &intf->altsetting[k];
+					if (intf_desc->bInterfaceClass == LIBUSB_CLASS_HID) {
+						interface_num = intf_desc->bInterfaceNumber;
+
+						/* Check the VID/PID against the arguments */
+						if ((vendor_id == 0x0 && product_id == 0x0) ||
+						    (vendor_id == dev_vid && product_id == dev_pid)) {
+							struct hid_device_info *tmp;
+
+							/* VID/PID match. Create the record. */
+							tmp = calloc(1, sizeof(struct hid_device_info));
+							if (cur_dev) {
+								cur_dev->next = tmp;
+							}
+							else {
+								root = tmp;
+							}
+							cur_dev = tmp;
+							
+							/* Fill out the record */
+							cur_dev->next = NULL;
+							cur_dev->path = make_path(dev, interface_num);
+							
+							res = libusb_open(dev, &handle);
+
+							if (res >= 0) {
+								/* Serial Number */
+								if (desc.iSerialNumber > 0)
+									cur_dev->serial_number =
+										get_usb_string(handle, desc.iSerialNumber);
+
+								/* Manufacturer and Product strings */
+								if (desc.iManufacturer > 0)
+									cur_dev->manufacturer_string =
+										get_usb_string(handle, desc.iManufacturer);
+								if (desc.iProduct > 0)
+									cur_dev->product_string =
+										get_usb_string(handle, desc.iProduct);
+
+#ifdef INVASIVE_GET_USAGE
+							/*
+							This section is removed because it is too
+							invasive on the system. Getting a Usage Page
+							and Usage requires parsing the HID Report
+							descriptor. Getting a HID Report descriptor
+							involves claiming the interface. Claiming the
+							interface involves detaching the kernel driver.
+							Detaching the kernel driver is hard on the system
+							because it will unclaim interfaces (if another
+							app has them claimed) and the re-attachment of
+							the driver will sometimes change /dev entry names.
+							It is for these reasons that this section is
+							#if 0. For composite devices, use the interface
+							field in the hid_device_info struct to distinguish
+							between interfaces. */
+								int detached = 0;
+								unsigned char data[256];
+							
+								/* Usage Page and Usage */
+								res = libusb_kernel_driver_active(handle, interface_num);
+								if (res == 1) {
+									res = libusb_detach_kernel_driver(handle, interface_num);
+									if (res < 0)
+										LOG("Couldn't detach kernel driver, even though a kernel driver was attached.");
+									else
+										detached = 1;
+								}
+								res = libusb_claim_interface(handle, interface_num);
+								if (res >= 0) {
+									/* Get the HID Report Descriptor. */
+									res = libusb_control_transfer(handle, LIBUSB_ENDPOINT_IN|LIBUSB_RECIPIENT_INTERFACE, LIBUSB_REQUEST_GET_DESCRIPTOR, (LIBUSB_DT_REPORT << 8)|interface_num, 0, data, sizeof(data), 5000);
+									if (res >= 0) {
+										unsigned short page=0, usage=0;
+										/* Parse the usage and usage page
+										   out of the report descriptor. */
+										get_usage(data, res,  &page, &usage);
+										cur_dev->usage_page = page;
+										cur_dev->usage = usage;
+									}
+									else
+										LOG("libusb_control_transfer() for getting the HID report failed with %d\n", res);
+
+									/* Release the interface */
+									res = libusb_release_interface(handle, interface_num);
+									if (res < 0)
+										LOG("Can't release the interface.\n");
+								}
+								else
+									LOG("Can't claim interface %d\n", res);
+
+								/* Re-attach kernel driver if necessary. */
+								if (detached) {
+									res = libusb_attach_kernel_driver(handle, interface_num);
+									if (res < 0)
+										LOG("Couldn't re-attach kernel driver.\n");
+								}
+#endif /*******************/
+
+								libusb_close(handle);
+							}
+							/* VID/PID */
+							cur_dev->vendor_id = dev_vid;
+							cur_dev->product_id = dev_pid;
+
+							/* Release Number */
+							cur_dev->release_number = desc.bcdDevice;
+							
+							/* Interface Number */
+							cur_dev->interface_number = interface_num;
+						}
+					}
+				} /* altsettings */
+			} /* interfaces */
+			libusb_free_config_descriptor(conf_desc);
+		}
+	}
+
+	libusb_free_device_list(devs, 1);
+
+	return root;
+}
+
+void  HID_API_EXPORT hid_free_enumeration(struct hid_device_info *devs)
+{
+	struct hid_device_info *d = devs;
+	while (d) {
+		struct hid_device_info *next = d->next;
+		free(d->path);
+		free(d->serial_number);
+		free(d->manufacturer_string);
+		free(d->product_string);
+		free(d);
+		d = next;
+	}
+}
+
+hid_device * hid_open(unsigned short vendor_id, unsigned short product_id, wchar_t *serial_number)
+{
+	struct hid_device_info *devs, *cur_dev;
+	const char *path_to_open = NULL;
+	hid_device *handle = NULL;
+	
+	devs = hid_enumerate(vendor_id, product_id);
+	cur_dev = devs;
+	while (cur_dev) {
+		if (cur_dev->vendor_id == vendor_id &&
+		    cur_dev->product_id == product_id) {
+			if (serial_number) {
+				if (wcscmp(serial_number, cur_dev->serial_number) == 0) {
+					path_to_open = cur_dev->path;
+					break;
+				}
+			}
+			else {
+				path_to_open = cur_dev->path;
+				break;
+			}
+		}
+		cur_dev = cur_dev->next;
+	}
+
+	if (path_to_open) {
+		/* Open the device */
+		handle = hid_open_path(path_to_open);
+	}
+
+	hid_free_enumeration(devs);
+	
+	return handle;
+}
+
+static void read_callback(struct libusb_transfer *transfer)
+{
+	hid_device *dev = transfer->user_data;
+	
+	if (transfer->status == LIBUSB_TRANSFER_COMPLETED) {
+
+		struct input_report *rpt = malloc(sizeof(*rpt));
+		rpt->data = malloc(transfer->actual_length);
+		memcpy(rpt->data, transfer->buffer, transfer->actual_length);
+		rpt->len = transfer->actual_length;
+		rpt->next = NULL;
+
+		pthread_mutex_lock(&dev->mutex);
+
+		/* Attach the new report object to the end of the list. */
+		if (dev->input_reports == NULL) {
+			/* The list is empty. Put it at the root. */
+			dev->input_reports = rpt;
+			pthread_cond_signal(&dev->condition);
+		}
+		else {
+			/* Find the end of the list and attach. */
+			struct input_report *cur = dev->input_reports;
+			int num_queued = 0;
+			while (cur->next != NULL) {
+				cur = cur->next;
+				num_queued++;
+			}
+			cur->next = rpt;
+			
+			/* Pop one off if we've reached 30 in the queue. This
+			   way we don't grow forever if the user never reads
+			   anything from the device. */
+			if (num_queued > 30) {
+				return_data(dev, NULL, 0);
+			}			
+		}
+		pthread_mutex_unlock(&dev->mutex);
+	}
+	else if (transfer->status == LIBUSB_TRANSFER_CANCELLED) {
+		dev->shutdown_thread = 1;
+		return;
+	}
+	else if (transfer->status == LIBUSB_TRANSFER_NO_DEVICE) {
+		dev->shutdown_thread = 1;
+		return;
+	}
+	else if (transfer->status == LIBUSB_TRANSFER_TIMED_OUT) {
+		//LOG("Timeout (normal)\n");
+	}
+	else {
+		LOG("Unknown transfer code: %d\n", transfer->status);
+	}
+	
+	/* Re-submit the transfer object. */
+	libusb_submit_transfer(transfer);
+}
+
+
+static void *read_thread(void *param)
+{
+	hid_device *dev = param;
+	unsigned char *buf;
+	const size_t length = dev->input_ep_max_packet_size;
+
+	/* Set up the transfer object. */
+	buf = malloc(length);
+	dev->transfer = libusb_alloc_transfer(0);
+	libusb_fill_interrupt_transfer(dev->transfer,
+		dev->device_handle,
+		dev->input_endpoint,
+		buf,
+		length,
+		read_callback,
+		dev,
+		5000/*timeout*/);
+	
+	/* Make the first submission. Further submissions are made
+	   from inside read_callback() */
+	libusb_submit_transfer(dev->transfer);
+
+	// Notify the main thread that the read thread is up and running.
+	pthread_barrier_wait(&dev->barrier);
+	
+	/* Handle all the events. */
+	while (!dev->shutdown_thread) {
+		int res;
+		res = libusb_handle_events(NULL);
+		if (res < 0) {
+			/* There was an error. Break out of this loop. */
+			break;
+		}
+	}
+	
+	/* Cancel any transfer that may be pending. This call will fail
+	   if no transfers are pending, but that's OK. */
+	if (libusb_cancel_transfer(dev->transfer) == 0) {
+		/* The transfer was cancelled, so wait for its completion. */
+		libusb_handle_events(NULL);
+	}
+	
+	/* Now that the read thread is stopping, Wake any threads which are
+	   waiting on data (in hid_read_timeout()). Do this under a mutex to
+	   make sure that a thread which is about to go to sleep waiting on
+	   the condition acutally will go to sleep before the condition is
+	   signaled. */
+	pthread_mutex_lock(&dev->mutex);
+	pthread_cond_broadcast(&dev->condition);
+	pthread_mutex_unlock(&dev->mutex);
+
+	/* The dev->transfer->buffer and dev->transfer objects are cleaned up
+	   in hid_close(). They are not cleaned up here because this thread
+	   could end either due to a disconnect or due to a user
+	   call to hid_close(). In both cases the objects can be safely
+	   cleaned up after the call to pthread_join() (in hid_close()), but
+	   since hid_close() calls libusb_cancel_transfer(), on these objects,
+	   they can not be cleaned up here. */
+	
+	return NULL;
+}
+
+
+hid_device * HID_API_EXPORT hid_open_path(const char *path)
+{
+	hid_device *dev = NULL;
+
+	dev = new_hid_device();
+
+	libusb_device **devs;
+	libusb_device *usb_dev;
+	ssize_t num_devs;
+	int res;
+	int d = 0;
+	int good_open = 0;
+	
+	setlocale(LC_ALL,"");
+	
+	if (!initialized)
+		hid_init();
+
+	num_devs = libusb_get_device_list(NULL, &devs);
+	while ((usb_dev = devs[d++]) != NULL) {
+		struct libusb_device_descriptor desc;
+		struct libusb_config_descriptor *conf_desc = NULL;
+		int i,j,k;
+		libusb_get_device_descriptor(usb_dev, &desc);
+
+		if (libusb_get_active_config_descriptor(usb_dev, &conf_desc) < 0)
+			continue;
+		for (j = 0; j < conf_desc->bNumInterfaces; j++) {
+			const struct libusb_interface *intf = &conf_desc->interface[j];
+			for (k = 0; k < intf->num_altsetting; k++) {
+				const struct libusb_interface_descriptor *intf_desc;
+				intf_desc = &intf->altsetting[k];
+				if (intf_desc->bInterfaceClass == LIBUSB_CLASS_HID) {
+					char *dev_path = make_path(usb_dev, intf_desc->bInterfaceNumber);
+					if (!strcmp(dev_path, path)) {
+						/* Matched Paths. Open this device */
+
+						// OPEN HERE //
+						res = libusb_open(usb_dev, &dev->device_handle);
+						if (res < 0) {
+							LOG("can't open device\n");
+							free(dev_path);
+ 							break;
+						}
+						good_open = 1;
+						
+						/* Detach the kernel driver, but only if the
+						   device is managed by the kernel */
+						if (libusb_kernel_driver_active(dev->device_handle, intf_desc->bInterfaceNumber) == 1) {
+							res = libusb_detach_kernel_driver(dev->device_handle, intf_desc->bInterfaceNumber);
+							if (res < 0) {
+								libusb_close(dev->device_handle);
+								LOG("Unable to detach Kernel Driver\n");
+								free(dev_path);
+								good_open = 0;
+								break;
+							}
+						}
+						
+						res = libusb_claim_interface(dev->device_handle, intf_desc->bInterfaceNumber);
+						if (res < 0) {
+							LOG("can't claim interface %d: %d\n", intf_desc->bInterfaceNumber, res);
+							free(dev_path);
+							libusb_close(dev->device_handle);
+							good_open = 0;
+							break;
+						}
+
+						/* Store off the string descriptor indexes */
+						dev->manufacturer_index = desc.iManufacturer;
+						dev->product_index      = desc.iProduct;
+						dev->serial_index       = desc.iSerialNumber;
+
+						/* Store off the interface number */
+						dev->interface = intf_desc->bInterfaceNumber;
+												
+						/* Find the INPUT and OUTPUT endpoints. An
+						   OUTPUT endpoint is not required. */
+						for (i = 0; i < intf_desc->bNumEndpoints; i++) {
+							const struct libusb_endpoint_descriptor *ep
+								= &intf_desc->endpoint[i];
+
+							/* Determine the type and direction of this
+							   endpoint. */
+							int is_interrupt =
+								(ep->bmAttributes & LIBUSB_TRANSFER_TYPE_MASK)
+							      == LIBUSB_TRANSFER_TYPE_INTERRUPT;
+							int is_output = 
+								(ep->bEndpointAddress & LIBUSB_ENDPOINT_DIR_MASK)
+							      == LIBUSB_ENDPOINT_OUT;
+							int is_input = 
+								(ep->bEndpointAddress & LIBUSB_ENDPOINT_DIR_MASK)
+							      == LIBUSB_ENDPOINT_IN;
+
+							/* Decide whether to use it for intput or output. */
+							if (dev->input_endpoint == 0 &&
+							    is_interrupt && is_input) {
+								/* Use this endpoint for INPUT */
+								dev->input_endpoint = ep->bEndpointAddress;
+								dev->input_ep_max_packet_size = ep->wMaxPacketSize;
+							}
+							if (dev->output_endpoint == 0 &&
+							    is_interrupt && is_output) {
+								/* Use this endpoint for OUTPUT */
+								dev->output_endpoint = ep->bEndpointAddress;
+							}
+						}
+						
+						pthread_create(&dev->thread, NULL, read_thread, dev);
+						
+						// Wait here for the read thread to be initialized.
+						pthread_barrier_wait(&dev->barrier);
+						
+					}
+					free(dev_path);
+				}
+			}
+		}
+		libusb_free_config_descriptor(conf_desc);
+
+	}
+
+	libusb_free_device_list(devs, 1);
+	
+	// If we have a good handle, return it.
+	if (good_open) {
+		return dev;
+	}
+	else {
+		// Unable to open any devices.
+		free_hid_device(dev);
+		return NULL;
+	}
+}
+
+
+int HID_API_EXPORT hid_write(hid_device *dev, const unsigned char *data, size_t length)
+{
+	int res;
+	int report_number = data[0];
+	int skipped_report_id = 0;
+
+	if (report_number == 0x0) {
+		data++;
+		length--;
+		skipped_report_id = 1;
+	}
+
+
+	if (dev->output_endpoint <= 0) {
+		/* No interrput out endpoint. Use the Control Endpoint */
+		res = libusb_control_transfer(dev->device_handle,
+			LIBUSB_REQUEST_TYPE_CLASS|LIBUSB_RECIPIENT_INTERFACE|LIBUSB_ENDPOINT_OUT,
+			0x09/*HID Set_Report*/,
+			(2/*HID output*/ << 8) | report_number,
+			dev->interface,
+			(unsigned char *)data, length,
+			1000/*timeout millis*/);
+		
+		if (res < 0)
+			return -1;
+		
+		if (skipped_report_id)
+			length++;
+		
+		return length;
+	}
+	else {
+		/* Use the interrupt out endpoint */
+		int actual_length;
+		res = libusb_interrupt_transfer(dev->device_handle,
+			dev->output_endpoint,
+			(unsigned char*)data,
+			length,
+			&actual_length, 1000);
+		
+		if (res < 0)
+			return -1;
+		
+		if (skipped_report_id)
+			actual_length++;
+		
+		return actual_length;
+	}
+}
+
+/* Helper function, to simplify hid_read().
+   This should be called with dev->mutex locked. */
+static int return_data(hid_device *dev, unsigned char *data, size_t length)
+{
+	/* Copy the data out of the linked list item (rpt) into the
+	   return buffer (data), and delete the liked list item. */
+	struct input_report *rpt = dev->input_reports;
+	size_t len = (length < rpt->len)? length: rpt->len;
+	if (len > 0)
+		memcpy(data, rpt->data, len);
+	dev->input_reports = rpt->next;
+	free(rpt->data);
+	free(rpt);
+	return len;
+}
+
+static void cleanup_mutex(void *param)
+{
+	hid_device *dev = param;
+	pthread_mutex_unlock(&dev->mutex);
+}
+
+
+int HID_API_EXPORT hid_read_timeout(hid_device *dev, unsigned char *data, size_t length, int milliseconds)
+{
+	int bytes_read = -1;
+
+#if 0
+	int transferred;
+	int res = libusb_interrupt_transfer(dev->device_handle, dev->input_endpoint, data, length, &transferred, 5000);
+	LOG("transferred: %d\n", transferred);
+	return transferred;
+#endif
+
+	pthread_mutex_lock(&dev->mutex);
+	pthread_cleanup_push(&cleanup_mutex, dev);
+
+	/* There's an input report queued up. Return it. */
+	if (dev->input_reports) {
+		/* Return the first one */
+		bytes_read = return_data(dev, data, length);
+		goto ret;
+	}
+	
+	if (dev->shutdown_thread) {
+		/* This means the device has been disconnected.
+		   An error code of -1 should be returned. */
+		bytes_read = -1;
+		goto ret;
+	}
+	
+	if (milliseconds == -1) {
+		/* Blocking */
+		while (!dev->input_reports && !dev->shutdown_thread) {
+			pthread_cond_wait(&dev->condition, &dev->mutex);
+		}
+		if (dev->input_reports) {
+			bytes_read = return_data(dev, data, length);
+		}
+	}
+	else if (milliseconds > 0) {
+		/* Non-blocking, but called with timeout. */
+		int res;
+		struct timespec ts;
+		clock_gettime(CLOCK_REALTIME, &ts);
+		ts.tv_sec += milliseconds / 1000;
+		ts.tv_nsec += (milliseconds % 1000) * 1000000;
+		if (ts.tv_nsec >= 1000000000L) {
+			ts.tv_sec++;
+			ts.tv_nsec -= 1000000000L;
+		}
+		
+		while (!dev->input_reports && !dev->shutdown_thread) {
+			res = pthread_cond_timedwait(&dev->condition, &dev->mutex, &ts);
+			if (res == 0) {
+				if (dev->input_reports) {
+					bytes_read = return_data(dev, data, length);
+					break;
+				}
+				
+				/* If we're here, there was a spurious wake up
+				   or the read thread was shutdown. Run the
+				   loop again (ie: don't break). */
+			}
+			else if (res == ETIMEDOUT) {
+				/* Timed out. */
+				bytes_read = 0;
+				break;
+			}
+			else {
+				/* Error. */
+				bytes_read = -1;
+				break;
+			}
+		}
+	}
+	else {
+		/* Purely non-blocking */
+		bytes_read = 0;
+	}
+
+ret:
+	pthread_mutex_unlock(&dev->mutex);
+	pthread_cleanup_pop(0);
+
+	return bytes_read;
+}
+
+int HID_API_EXPORT hid_read(hid_device *dev, unsigned char *data, size_t length)
+{
+	return hid_read_timeout(dev, data, length, dev->blocking ? -1 : 0);
+}
+
+int HID_API_EXPORT hid_set_nonblocking(hid_device *dev, int nonblock)
+{
+	dev->blocking = !nonblock;
+	
+	return 0;
+}
+
+
+int HID_API_EXPORT hid_send_feature_report(hid_device *dev, const unsigned char *data, size_t length)
+{
+	int res = -1;
+	int skipped_report_id = 0;
+	int report_number = data[0];
+
+	if (report_number == 0x0) {
+		data++;
+		length--;
+		skipped_report_id = 1;
+	}
+
+	res = libusb_control_transfer(dev->device_handle,
+		LIBUSB_REQUEST_TYPE_CLASS|LIBUSB_RECIPIENT_INTERFACE|LIBUSB_ENDPOINT_OUT,
+		0x09/*HID set_report*/,
+		(3/*HID feature*/ << 8) | report_number,
+		dev->interface,
+		(unsigned char *)data, length,
+		1000/*timeout millis*/);
+	
+	if (res < 0)
+		return -1;
+	
+	/* Account for the report ID */
+	if (skipped_report_id)
+		length++;
+	
+	return length;
+}
+
+int HID_API_EXPORT hid_get_feature_report(hid_device *dev, unsigned char *data, size_t length)
+{
+	int res = -1;
+	int skipped_report_id = 0;
+	int report_number = data[0];
+
+	if (report_number == 0x0) {
+		/* Offset the return buffer by 1, so that the report ID
+		   will remain in byte 0. */
+		data++;
+		length--;
+		skipped_report_id = 1;
+	}
+	res = libusb_control_transfer(dev->device_handle,
+		LIBUSB_REQUEST_TYPE_CLASS|LIBUSB_RECIPIENT_INTERFACE|LIBUSB_ENDPOINT_IN,
+		0x01/*HID get_report*/,
+		(3/*HID feature*/ << 8) | report_number,
+		dev->interface,
+		(unsigned char *)data, length,
+		1000/*timeout millis*/);
+	
+	if (res < 0)
+		return -1;
+
+	if (skipped_report_id)
+		res++;
+	
+	return res;
+}
+
+
+void HID_API_EXPORT hid_close(hid_device *dev)
+{
+	if (!dev)
+		return;
+	
+	/* Cause read_thread() to stop. */
+	dev->shutdown_thread = 1;
+	libusb_cancel_transfer(dev->transfer);
+
+	/* Wait for read_thread() to end. */
+	pthread_join(dev->thread, NULL);
+	
+	/* Clean up the Transfer objects allocated in read_thread(). */
+	free(dev->transfer->buffer);
+	libusb_free_transfer(dev->transfer);
+	
+	/* release the interface */
+	libusb_release_interface(dev->device_handle, dev->interface);
+	
+	/* Close the handle */
+	libusb_close(dev->device_handle);
+	
+	/* Clear out the queue of received reports. */
+	pthread_mutex_lock(&dev->mutex);
+	while (dev->input_reports) {
+		return_data(dev, NULL, 0);
+	}
+	pthread_mutex_unlock(&dev->mutex);
+	
+	free_hid_device(dev);
+}
+
+
+int HID_API_EXPORT_CALL hid_get_manufacturer_string(hid_device *dev, wchar_t *string, size_t maxlen)
+{
+	return hid_get_indexed_string(dev, dev->manufacturer_index, string, maxlen);
+}
+
+int HID_API_EXPORT_CALL hid_get_product_string(hid_device *dev, wchar_t *string, size_t maxlen)
+{
+	return hid_get_indexed_string(dev, dev->product_index, string, maxlen);
+}
+
+int HID_API_EXPORT_CALL hid_get_serial_number_string(hid_device *dev, wchar_t *string, size_t maxlen)
+{
+	return hid_get_indexed_string(dev, dev->serial_index, string, maxlen);
+}
+
+int HID_API_EXPORT_CALL hid_get_indexed_string(hid_device *dev, int string_index, wchar_t *string, size_t maxlen)
+{
+	wchar_t *str;
+
+	str = get_usb_string(dev->device_handle, string_index);
+	if (str) {
+		wcsncpy(string, str, maxlen);
+		string[maxlen-1] = L'\0';
+		free(str);
+		return 0;
+	}
+	else
+		return -1;
+}
+
+
+HID_API_EXPORT const wchar_t * HID_API_CALL  hid_error(hid_device *dev)
+{
+	return NULL;
+}
+
+
+struct lang_map_entry {
+	const char *name;
+	const char *string_code;
+	uint16_t usb_code;
+};
+
+#define LANG(name,code,usb_code) { name, code, usb_code }
+static struct lang_map_entry lang_map[] = {
+	LANG("Afrikaans", "af", 0x0436),
+	LANG("Albanian", "sq", 0x041C),
+	LANG("Arabic - United Arab Emirates", "ar_ae", 0x3801),
+	LANG("Arabic - Bahrain", "ar_bh", 0x3C01),
+	LANG("Arabic - Algeria", "ar_dz", 0x1401),
+	LANG("Arabic - Egypt", "ar_eg", 0x0C01),
+	LANG("Arabic - Iraq", "ar_iq", 0x0801),
+	LANG("Arabic - Jordan", "ar_jo", 0x2C01),
+	LANG("Arabic - Kuwait", "ar_kw", 0x3401),
+	LANG("Arabic - Lebanon", "ar_lb", 0x3001),
+	LANG("Arabic - Libya", "ar_ly", 0x1001),
+	LANG("Arabic - Morocco", "ar_ma", 0x1801),
+	LANG("Arabic - Oman", "ar_om", 0x2001),
+	LANG("Arabic - Qatar", "ar_qa", 0x4001),
+	LANG("Arabic - Saudi Arabia", "ar_sa", 0x0401),
+	LANG("Arabic - Syria", "ar_sy", 0x2801),
+	LANG("Arabic - Tunisia", "ar_tn", 0x1C01),
+	LANG("Arabic - Yemen", "ar_ye", 0x2401),
+	LANG("Armenian", "hy", 0x042B),
+	LANG("Azeri - Latin", "az_az", 0x042C),
+	LANG("Azeri - Cyrillic", "az_az", 0x082C),
+	LANG("Basque", "eu", 0x042D),
+	LANG("Belarusian", "be", 0x0423),
+	LANG("Bulgarian", "bg", 0x0402),
+	LANG("Catalan", "ca", 0x0403),
+	LANG("Chinese - China", "zh_cn", 0x0804),
+	LANG("Chinese - Hong Kong SAR", "zh_hk", 0x0C04),
+	LANG("Chinese - Macau SAR", "zh_mo", 0x1404),
+	LANG("Chinese - Singapore", "zh_sg", 0x1004),
+	LANG("Chinese - Taiwan", "zh_tw", 0x0404),
+	LANG("Croatian", "hr", 0x041A),
+	LANG("Czech", "cs", 0x0405),
+	LANG("Danish", "da", 0x0406),
+	LANG("Dutch - Netherlands", "nl_nl", 0x0413),
+	LANG("Dutch - Belgium", "nl_be", 0x0813),
+	LANG("English - Australia", "en_au", 0x0C09),
+	LANG("English - Belize", "en_bz", 0x2809),
+	LANG("English - Canada", "en_ca", 0x1009),
+	LANG("English - Caribbean", "en_cb", 0x2409),
+	LANG("English - Ireland", "en_ie", 0x1809),
+	LANG("English - Jamaica", "en_jm", 0x2009),
+	LANG("English - New Zealand", "en_nz", 0x1409),
+	LANG("English - Phillippines", "en_ph", 0x3409),
+	LANG("English - Southern Africa", "en_za", 0x1C09),
+	LANG("English - Trinidad", "en_tt", 0x2C09),
+	LANG("English - Great Britain", "en_gb", 0x0809),
+	LANG("English - United States", "en_us", 0x0409),
+	LANG("Estonian", "et", 0x0425),
+	LANG("Farsi", "fa", 0x0429),
+	LANG("Finnish", "fi", 0x040B),
+	LANG("Faroese", "fo", 0x0438),
+	LANG("French - France", "fr_fr", 0x040C),
+	LANG("French - Belgium", "fr_be", 0x080C),
+	LANG("French - Canada", "fr_ca", 0x0C0C),
+	LANG("French - Luxembourg", "fr_lu", 0x140C),
+	LANG("French - Switzerland", "fr_ch", 0x100C),
+	LANG("Gaelic - Ireland", "gd_ie", 0x083C),
+	LANG("Gaelic - Scotland", "gd", 0x043C),
+	LANG("German - Germany", "de_de", 0x0407),
+	LANG("German - Austria", "de_at", 0x0C07),
+	LANG("German - Liechtenstein", "de_li", 0x1407),
+	LANG("German - Luxembourg", "de_lu", 0x1007),
+	LANG("German - Switzerland", "de_ch", 0x0807),
+	LANG("Greek", "el", 0x0408),
+	LANG("Hebrew", "he", 0x040D),
+	LANG("Hindi", "hi", 0x0439),
+	LANG("Hungarian", "hu", 0x040E),
+	LANG("Icelandic", "is", 0x040F),
+	LANG("Indonesian", "id", 0x0421),
+	LANG("Italian - Italy", "it_it", 0x0410),
+	LANG("Italian - Switzerland", "it_ch", 0x0810),
+	LANG("Japanese", "ja", 0x0411),
+	LANG("Korean", "ko", 0x0412),
+	LANG("Latvian", "lv", 0x0426),
+	LANG("Lithuanian", "lt", 0x0427),
+	LANG("F.Y.R.O. Macedonia", "mk", 0x042F),
+	LANG("Malay - Malaysia", "ms_my", 0x043E),
+	LANG("Malay – Brunei", "ms_bn", 0x083E),
+	LANG("Maltese", "mt", 0x043A),
+	LANG("Marathi", "mr", 0x044E),
+	LANG("Norwegian - Bokml", "no_no", 0x0414),
+	LANG("Norwegian - Nynorsk", "no_no", 0x0814),
+	LANG("Polish", "pl", 0x0415),
+	LANG("Portuguese - Portugal", "pt_pt", 0x0816),
+	LANG("Portuguese - Brazil", "pt_br", 0x0416),
+	LANG("Raeto-Romance", "rm", 0x0417),
+	LANG("Romanian - Romania", "ro", 0x0418),
+	LANG("Romanian - Republic of Moldova", "ro_mo", 0x0818),
+	LANG("Russian", "ru", 0x0419),
+	LANG("Russian - Republic of Moldova", "ru_mo", 0x0819),
+	LANG("Sanskrit", "sa", 0x044F),
+	LANG("Serbian - Cyrillic", "sr_sp", 0x0C1A),
+	LANG("Serbian - Latin", "sr_sp", 0x081A),
+	LANG("Setsuana", "tn", 0x0432),
+	LANG("Slovenian", "sl", 0x0424),
+	LANG("Slovak", "sk", 0x041B),
+	LANG("Sorbian", "sb", 0x042E),
+	LANG("Spanish - Spain (Traditional)", "es_es", 0x040A),
+	LANG("Spanish - Argentina", "es_ar", 0x2C0A),
+	LANG("Spanish - Bolivia", "es_bo", 0x400A),
+	LANG("Spanish - Chile", "es_cl", 0x340A),
+	LANG("Spanish - Colombia", "es_co", 0x240A),
+	LANG("Spanish - Costa Rica", "es_cr", 0x140A),
+	LANG("Spanish - Dominican Republic", "es_do", 0x1C0A),
+	LANG("Spanish - Ecuador", "es_ec", 0x300A),
+	LANG("Spanish - Guatemala", "es_gt", 0x100A),
+	LANG("Spanish - Honduras", "es_hn", 0x480A),
+	LANG("Spanish - Mexico", "es_mx", 0x080A),
+	LANG("Spanish - Nicaragua", "es_ni", 0x4C0A),
+	LANG("Spanish - Panama", "es_pa", 0x180A),
+	LANG("Spanish - Peru", "es_pe", 0x280A),
+	LANG("Spanish - Puerto Rico", "es_pr", 0x500A),
+	LANG("Spanish - Paraguay", "es_py", 0x3C0A),
+	LANG("Spanish - El Salvador", "es_sv", 0x440A),
+	LANG("Spanish - Uruguay", "es_uy", 0x380A),
+	LANG("Spanish - Venezuela", "es_ve", 0x200A),
+	LANG("Southern Sotho", "st", 0x0430),
+	LANG("Swahili", "sw", 0x0441),
+	LANG("Swedish - Sweden", "sv_se", 0x041D),
+	LANG("Swedish - Finland", "sv_fi", 0x081D),
+	LANG("Tamil", "ta", 0x0449),
+	LANG("Tatar", "tt", 0X0444),
+	LANG("Thai", "th", 0x041E),
+	LANG("Turkish", "tr", 0x041F),
+	LANG("Tsonga", "ts", 0x0431),
+	LANG("Ukrainian", "uk", 0x0422),
+	LANG("Urdu", "ur", 0x0420),
+	LANG("Uzbek - Cyrillic", "uz_uz", 0x0843),
+	LANG("Uzbek – Latin", "uz_uz", 0x0443),
+	LANG("Vietnamese", "vi", 0x042A),
+	LANG("Xhosa", "xh", 0x0434),
+	LANG("Yiddish", "yi", 0x043D),
+	LANG("Zulu", "zu", 0x0435),
+	LANG(NULL, NULL, 0x0),	
+};
+
+uint16_t get_usb_code_for_current_locale(void)
+{
+	char *locale;
+	char search_string[64];
+	char *ptr;
+	
+	/* Get the current locale. */
+	locale = setlocale(0, NULL);
+	if (!locale)
+		return 0x0;
+	
+	/* Make a copy of the current locale string. */
+	strncpy(search_string, locale, sizeof(search_string));
+	search_string[sizeof(search_string)-1] = '\0';
+	
+	/* Chop off the encoding part, and make it lower case. */
+	ptr = search_string;
+	while (*ptr) {
+		*ptr = tolower(*ptr);
+		if (*ptr == '.') {
+			*ptr = '\0';
+			break;
+		}
+		ptr++;
+	}
+
+	/* Find the entry which matches the string code of our locale. */
+	struct lang_map_entry *lang = lang_map;
+	while (lang->string_code) {
+		if (!strcmp(lang->string_code, search_string)) {
+			return lang->usb_code;
+		}	
+		lang++;
+	}
+	
+	/* There was no match. Find with just the language only. */
+	/* Chop off the variant. Chop it off at the '_'. */
+	ptr = search_string;
+	while (*ptr) {
+		*ptr = tolower(*ptr);
+		if (*ptr == '_') {
+			*ptr = '\0';
+			break;
+		}
+		ptr++;
+	}
+	
+#if 0 // TODO: Do we need this?
+	/* Find the entry which matches the string code of our language. */
+	lang = lang_map;
+	while (lang->string_code) {
+		if (!strcmp(lang->string_code, search_string)) {
+			return lang->usb_code;
+		}	
+		lang++;
+	}
+#endif
+	
+	/* Found nothing. */
+	return 0x0;
+}
+
+#ifdef __cplusplus
+}
+#endif