/*
 * In this module we implement the function that locates a USB device
 * by bus and device number/filename strings.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <usb.h>
#include "find_dev.h"
#include "prelim_init.h"

struct usb_device *
find_usbdev_by_busdev(const char *bus_dev_spec)
{
	const char *slash;
	unsigned bus_name_len;
	struct usb_bus *bus;
	struct usb_device *dev;

	slash = index(bus_dev_spec, '/');
	if (!slash) {
		fprintf(stderr,
			"error: bus/dev path expected, but no slash found\n");
		exit(1);
	}
	bus_name_len = slash - bus_dev_spec;
	libusb_prelim_init();
	for (bus = usb_get_busses(); bus; bus = bus->next) {
		if (strlen(bus->dirname) != bus_name_len)
			continue;
		if (strncmp(bus->dirname, bus_dev_spec, bus_name_len))
			continue;
		for (dev = bus->devices; dev; dev = dev->next) {
			if (!strcmp(dev->filename, slash + 1))
				return dev;
		}
	}
	return 0;
}