1 /* -*- Mode: C; indent-tabs-mode:t ; c-basic-offset:8 -*- */
2 /*
3  * libusb example program for hotplug API
4  * Copyright © 2012-2013 Nathan Hjelm <hjelmn@mac.com>
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include <stdlib.h>
22 #include <stdio.h>
23 
24 #include "libusb.h"
25 
26 int done = 0;
27 libusb_device_handle *handle = NULL;
28 
hotplug_callback(libusb_context * ctx,libusb_device * dev,libusb_hotplug_event event,void * user_data)29 static int LIBUSB_CALL hotplug_callback(libusb_context *ctx, libusb_device *dev, libusb_hotplug_event event, void *user_data)
30 {
31 	struct libusb_device_descriptor desc;
32 	int rc;
33 
34 	(void)ctx;
35 	(void)dev;
36 	(void)event;
37 	(void)user_data;
38 
39 	rc = libusb_get_device_descriptor(dev, &desc);
40 	if (LIBUSB_SUCCESS != rc) {
41 		fprintf (stderr, "Error getting device descriptor\n");
42 	}
43 
44 	printf ("Device attached: %04x:%04x\n", desc.idVendor, desc.idProduct);
45 
46 	if (handle) {
47 		libusb_close (handle);
48 		handle = NULL;
49 	}
50 
51 	rc = libusb_open (dev, &handle);
52 	if (LIBUSB_SUCCESS != rc) {
53 		fprintf (stderr, "Error opening device\n");
54 	}
55 
56 	done++;
57 
58 	return 0;
59 }
60 
hotplug_callback_detach(libusb_context * ctx,libusb_device * dev,libusb_hotplug_event event,void * user_data)61 static int LIBUSB_CALL hotplug_callback_detach(libusb_context *ctx, libusb_device *dev, libusb_hotplug_event event, void *user_data)
62 {
63 	(void)ctx;
64 	(void)dev;
65 	(void)event;
66 	(void)user_data;
67 
68 	printf ("Device detached\n");
69 
70 	if (handle) {
71 		libusb_close (handle);
72 		handle = NULL;
73 	}
74 
75 	done++;
76 
77 	return 0;
78 }
79 
main(int argc,char * argv[])80 int main(int argc, char *argv[])
81 {
82 	libusb_hotplug_callback_handle hp[2];
83 	int product_id, vendor_id, class_id;
84 	int rc;
85 
86 	vendor_id  = (argc > 1) ? (int)strtol (argv[1], NULL, 0) : 0x045a;
87 	product_id = (argc > 2) ? (int)strtol (argv[2], NULL, 0) : 0x5005;
88 	class_id   = (argc > 3) ? (int)strtol (argv[3], NULL, 0) : LIBUSB_HOTPLUG_MATCH_ANY;
89 
90 	rc = libusb_init (NULL);
91 	if (rc < 0)
92 	{
93 		printf("failed to initialise libusb: %s\n", libusb_error_name(rc));
94 		return EXIT_FAILURE;
95 	}
96 
97 	if (!libusb_has_capability (LIBUSB_CAP_HAS_HOTPLUG)) {
98 		printf ("Hotplug capabilities are not supported on this platform\n");
99 		libusb_exit (NULL);
100 		return EXIT_FAILURE;
101 	}
102 
103 	rc = libusb_hotplug_register_callback (NULL, LIBUSB_HOTPLUG_EVENT_DEVICE_ARRIVED, 0, vendor_id,
104 		product_id, class_id, hotplug_callback, NULL, &hp[0]);
105 	if (LIBUSB_SUCCESS != rc) {
106 		fprintf (stderr, "Error registering callback 0\n");
107 		libusb_exit (NULL);
108 		return EXIT_FAILURE;
109 	}
110 
111 	rc = libusb_hotplug_register_callback (NULL, LIBUSB_HOTPLUG_EVENT_DEVICE_LEFT, 0, vendor_id,
112 		product_id,class_id, hotplug_callback_detach, NULL, &hp[1]);
113 	if (LIBUSB_SUCCESS != rc) {
114 		fprintf (stderr, "Error registering callback 1\n");
115 		libusb_exit (NULL);
116 		return EXIT_FAILURE;
117 	}
118 
119 	while (done < 2) {
120 		rc = libusb_handle_events (NULL);
121 		if (rc < 0)
122 			printf("libusb_handle_events() failed: %s\n", libusb_error_name(rc));
123 	}
124 
125 	if (handle) {
126 		libusb_close (handle);
127 	}
128 
129 	libusb_exit (NULL);
130 
131 	return EXIT_SUCCESS;
132 }
133