1 /*******************************************************
2  HIDAPI - Multi-Platform library for
3  communication with HID devices.
4 
5  Alan Ott
6  Signal 11 Software
7 
8  8/22/2009
9 
10  Copyright 2009, All Rights Reserved.
11 
12  At the discretion of the user of this library,
13  this software may be licensed under the terms of the
14  GNU General Public License v3, a BSD-Style license, or the
15  original HIDAPI license as outlined in the LICENSE.txt,
16  LICENSE-gpl3.txt, LICENSE-bsd.txt, and LICENSE-orig.txt
17  files located at the root of the source distribution.
18  These files may also be found in the public source
19  code repository located at:
20         https://github.com/libusb/hidapi .
21 ********************************************************/
22 
23 /** @file
24  * @defgroup API hidapi API
25  */
26 
27 #ifndef HIDAPI_H__
28 #define HIDAPI_H__
29 
30 #include <wchar.h>
31 
32 #if defined(_WIN32) && !defined(NAMESPACE) && (0) /* SDL: don't export hidapi syms */
33       #define HID_API_EXPORT __declspec(dllexport)
34       #define HID_API_CALL
35 #else
36 #ifndef HID_API_EXPORT
37       #define HID_API_EXPORT /**< API export macro */
38 #endif
39 #ifndef HID_API_CALL
40       #define HID_API_CALL /**< API call macro */
41 #endif
42 #endif
43 
44 #define HID_API_EXPORT_CALL HID_API_EXPORT HID_API_CALL /**< API export and call macro*/
45 
46 #if defined(__cplusplus) && !defined(NAMESPACE)
47 extern "C" {
48 #endif
49 #ifdef NAMESPACE
50 namespace NAMESPACE {
51 #endif
52 
53 		struct hid_device_;
54 		typedef struct hid_device_ hid_device; /**< opaque hidapi structure */
55 
56 		/** hidapi info structure */
57 		struct hid_device_info {
58 			/** Platform-specific device path */
59 			char *path;
60 			/** Device Vendor ID */
61 			unsigned short vendor_id;
62 			/** Device Product ID */
63 			unsigned short product_id;
64 			/** Serial Number */
65 			wchar_t *serial_number;
66 			/** Device Release Number in binary-coded decimal,
67 			    also known as Device Version Number */
68 			unsigned short release_number;
69 			/** Manufacturer String */
70 			wchar_t *manufacturer_string;
71 			/** Product string */
72 			wchar_t *product_string;
73 			/** Usage Page for this Device/Interface
74 			    (Windows/Mac only). */
75 			unsigned short usage_page;
76 			/** Usage for this Device/Interface
77 			    (Windows/Mac only).*/
78 			unsigned short usage;
79 			/** The USB interface which this logical device
80 			    represents. Valid on both Linux implementations
81 			    in all cases, and valid on the Windows implementation
82 			    only if the device contains more than one interface. */
83 			int interface_number;
84 
85 			/** Additional information about the USB interface.
86 			    Valid on libusb and Android implementations. */
87 			int interface_class;
88 			int interface_subclass;
89 			int interface_protocol;
90 
91 			/** Pointer to the next device */
92 			struct hid_device_info *next;
93 		};
94 
95 
96 		/** @brief Initialize the HIDAPI library.
97 
98 			This function initializes the HIDAPI library. Calling it is not
99 			strictly necessary, as it will be called automatically by
100 			hid_enumerate() and any of the hid_open_*() functions if it is
101 			needed.  This function should be called at the beginning of
102 			execution however, if there is a chance of HIDAPI handles
103 			being opened by different threads simultaneously.
104 
105 			@ingroup API
106 
107 			@returns
108 				This function returns 0 on success and -1 on error.
109 		*/
110 		int HID_API_EXPORT HID_API_CALL hid_init(void);
111 
112 		/** @brief Finalize the HIDAPI library.
113 
114 			This function frees all of the static data associated with
115 			HIDAPI. It should be called at the end of execution to avoid
116 			memory leaks.
117 
118 			@ingroup API
119 
120 		    @returns
121 				This function returns 0 on success and -1 on error.
122 		*/
123 		int HID_API_EXPORT HID_API_CALL hid_exit(void);
124 
125 		/** @brief Enumerate the HID Devices.
126 
127 			This function returns a linked list of all the HID devices
128 			attached to the system which match vendor_id and product_id.
129 			If @p vendor_id is set to 0 then any vendor matches.
130 			If @p product_id is set to 0 then any product matches.
131 			If @p vendor_id and @p product_id are both set to 0, then
132 			all HID devices will be returned.
133 
134 			@ingroup API
135 			@param vendor_id The Vendor ID (VID) of the types of device
136 				to open.
137 			@param product_id The Product ID (PID) of the types of
138 				device to open.
139 
140 		    @returns
141 		    	This function returns a pointer to a linked list of type
142 		    	struct #hid_device, containing information about the HID devices
143 		    	attached to the system, or NULL in the case of failure. Free
144 		    	this linked list by calling hid_free_enumeration().
145 		*/
146 		struct hid_device_info HID_API_EXPORT * HID_API_CALL hid_enumerate(unsigned short vendor_id, unsigned short product_id);
147 
148 		/** @brief Free an enumeration Linked List
149 
150 		    This function frees a linked list created by hid_enumerate().
151 
152 			@ingroup API
153 		    @param devs Pointer to a list of struct_device returned from
154 		    	      hid_enumerate().
155 		*/
156 		void  HID_API_EXPORT HID_API_CALL hid_free_enumeration(struct hid_device_info *devs);
157 
158 		/** @brief Open a HID device using a Vendor ID (VID), Product ID
159 			(PID) and optionally a serial number.
160 
161 			If @p serial_number is NULL, the first device with the
162 			specified VID and PID is opened.
163 
164 			@ingroup API
165 			@param vendor_id The Vendor ID (VID) of the device to open.
166 			@param product_id The Product ID (PID) of the device to open.
167 			@param serial_number The Serial Number of the device to open
168 				               (Optionally NULL).
169 
170 			@returns
171 				This function returns a pointer to a #hid_device object on
172 				success or NULL on failure.
173 		*/
174 		HID_API_EXPORT hid_device * HID_API_CALL hid_open(unsigned short vendor_id, unsigned short product_id, const wchar_t *serial_number);
175 
176 		/** @brief Open a HID device by its path name.
177 
178 			The path name be determined by calling hid_enumerate(), or a
179 			platform-specific path name can be used (eg: /dev/hidraw0 on
180 			Linux).
181 
182 			@ingroup API
183 		    @param path The path name of the device to open
184 
185 			@returns
186 				This function returns a pointer to a #hid_device object on
187 				success or NULL on failure.
188 		*/
189 		HID_API_EXPORT hid_device * HID_API_CALL hid_open_path(const char *path, int bExclusive /* = false */);
190 
191 		/** @brief Write an Output report to a HID device.
192 
193 			The first byte of @p data[] must contain the Report ID. For
194 			devices which only support a single report, this must be set
195 			to 0x0. The remaining bytes contain the report data. Since
196 			the Report ID is mandatory, calls to hid_write() will always
197 			contain one more byte than the report contains. For example,
198 			if a hid report is 16 bytes long, 17 bytes must be passed to
199 			hid_write(), the Report ID (or 0x0, for devices with a
200 			single report), followed by the report data (16 bytes). In
201 			this example, the length passed in would be 17.
202 
203 			hid_write() will send the data on the first OUT endpoint, if
204 			one exists. If it does not, it will send the data through
205 			the Control Endpoint (Endpoint 0).
206 
207 			@ingroup API
208 			@param device A device handle returned from hid_open().
209 			@param data The data to send, including the report number as
210 				the first byte.
211 			@param length The length in bytes of the data to send.
212 
213 			@returns
214 				This function returns the actual number of bytes written and
215 				-1 on error.
216 		*/
217 		int  HID_API_EXPORT HID_API_CALL hid_write(hid_device *device, const unsigned char *data, size_t length);
218 
219 		/** @brief Read an Input report from a HID device with timeout.
220 
221 			Input reports are returned
222 			to the host through the INTERRUPT IN endpoint. The first byte will
223 			contain the Report number if the device uses numbered reports.
224 
225 			@ingroup API
226 			@param device A device handle returned from hid_open().
227 			@param data A buffer to put the read data into.
228 			@param length The number of bytes to read. For devices with
229 				multiple reports, make sure to read an extra byte for
230 				the report number.
231 			@param milliseconds timeout in milliseconds or -1 for blocking wait.
232 
233 			@returns
234 				This function returns the actual number of bytes read and
235 				-1 on error. If no packet was available to be read within
236 				the timeout period, this function returns 0.
237 		*/
238 		int HID_API_EXPORT HID_API_CALL hid_read_timeout(hid_device *device, unsigned char *data, size_t length, int milliseconds);
239 
240 		/** @brief Read an Input report from a HID device.
241 
242 			Input reports are returned
243 		    to the host through the INTERRUPT IN endpoint. The first byte will
244 			contain the Report number if the device uses numbered reports.
245 
246 			@ingroup API
247 			@param device A device handle returned from hid_open().
248 			@param data A buffer to put the read data into.
249 			@param length The number of bytes to read. For devices with
250 				multiple reports, make sure to read an extra byte for
251 				the report number.
252 
253 			@returns
254 				This function returns the actual number of bytes read and
255 				-1 on error. If no packet was available to be read and
256 				the handle is in non-blocking mode, this function returns 0.
257 		*/
258 		int  HID_API_EXPORT HID_API_CALL hid_read(hid_device *device, unsigned char *data, size_t length);
259 
260 		/** @brief Set the device handle to be non-blocking.
261 
262 			In non-blocking mode calls to hid_read() will return
263 			immediately with a value of 0 if there is no data to be
264 			read. In blocking mode, hid_read() will wait (block) until
265 			there is data to read before returning.
266 
267 			Nonblocking can be turned on and off at any time.
268 
269 			@ingroup API
270 			@param device A device handle returned from hid_open().
271 			@param nonblock enable or not the nonblocking reads
272 			 - 1 to enable nonblocking
273 			 - 0 to disable nonblocking.
274 
275 			@returns
276 				This function returns 0 on success and -1 on error.
277 		*/
278 		int  HID_API_EXPORT HID_API_CALL hid_set_nonblocking(hid_device *device, int nonblock);
279 
280 		/** @brief Send a Feature report to the device.
281 
282 			Feature reports are sent over the Control endpoint as a
283 			Set_Report transfer.  The first byte of @p data[] must
284 			contain the Report ID. For devices which only support a
285 			single report, this must be set to 0x0. The remaining bytes
286 			contain the report data. Since the Report ID is mandatory,
287 			calls to hid_send_feature_report() will always contain one
288 			more byte than the report contains. For example, if a hid
289 			report is 16 bytes long, 17 bytes must be passed to
290 			hid_send_feature_report(): the Report ID (or 0x0, for
291 			devices which do not use numbered reports), followed by the
292 			report data (16 bytes). In this example, the length passed
293 			in would be 17.
294 
295 			@ingroup API
296 			@param device A device handle returned from hid_open().
297 			@param data The data to send, including the report number as
298 				the first byte.
299 			@param length The length in bytes of the data to send, including
300 				the report number.
301 
302 			@returns
303 				This function returns the actual number of bytes written and
304 				-1 on error.
305 		*/
306 		int HID_API_EXPORT HID_API_CALL hid_send_feature_report(hid_device *device, const unsigned char *data, size_t length);
307 
308 		/** @brief Get a feature report from a HID device.
309 
310 			Set the first byte of @p data[] to the Report ID of the
311 			report to be read.  Make sure to allow space for this
312 			extra byte in @p data[]. Upon return, the first byte will
313 			still contain the Report ID, and the report data will
314 			start in data[1].
315 
316 			@ingroup API
317 			@param device A device handle returned from hid_open().
318 			@param data A buffer to put the read data into, including
319 				the Report ID. Set the first byte of @p data[] to the
320 				Report ID of the report to be read, or set it to zero
321 				if your device does not use numbered reports.
322 			@param length The number of bytes to read, including an
323 				extra byte for the report ID. The buffer can be longer
324 				than the actual report.
325 
326 			@returns
327 				This function returns the number of bytes read plus
328 				one for the report ID (which is still in the first
329 				byte), or -1 on error.
330 		*/
331 		int HID_API_EXPORT HID_API_CALL hid_get_feature_report(hid_device *device, unsigned char *data, size_t length);
332 
333 		/** @brief Close a HID device.
334 
335 			@ingroup API
336 			@param device A device handle returned from hid_open().
337 		*/
338 		void HID_API_EXPORT HID_API_CALL hid_close(hid_device *device);
339 
340 		/** @brief Get The Manufacturer String from a HID device.
341 
342 			@ingroup API
343 			@param device A device handle returned from hid_open().
344 			@param string A wide string buffer to put the data into.
345 			@param maxlen The length of the buffer in multiples of wchar_t.
346 
347 			@returns
348 				This function returns 0 on success and -1 on error.
349 		*/
350 		int HID_API_EXPORT_CALL hid_get_manufacturer_string(hid_device *device, wchar_t *string, size_t maxlen);
351 
352 		/** @brief Get The Product String from a HID device.
353 
354 			@ingroup API
355 			@param device A device handle returned from hid_open().
356 			@param string A wide string buffer to put the data into.
357 			@param maxlen The length of the buffer in multiples of wchar_t.
358 
359 			@returns
360 				This function returns 0 on success and -1 on error.
361 		*/
362 		int HID_API_EXPORT_CALL hid_get_product_string(hid_device *device, wchar_t *string, size_t maxlen);
363 
364 		/** @brief Get The Serial Number String from a HID device.
365 
366 			@ingroup API
367 			@param device A device handle returned from hid_open().
368 			@param string A wide string buffer to put the data into.
369 			@param maxlen The length of the buffer in multiples of wchar_t.
370 
371 			@returns
372 				This function returns 0 on success and -1 on error.
373 		*/
374 		int HID_API_EXPORT_CALL hid_get_serial_number_string(hid_device *device, wchar_t *string, size_t maxlen);
375 
376 		/** @brief Get a string from a HID device, based on its string index.
377 
378 			@ingroup API
379 			@param device A device handle returned from hid_open().
380 			@param string_index The index of the string to get.
381 			@param string A wide string buffer to put the data into.
382 			@param maxlen The length of the buffer in multiples of wchar_t.
383 
384 			@returns
385 				This function returns 0 on success and -1 on error.
386 		*/
387 		int HID_API_EXPORT_CALL hid_get_indexed_string(hid_device *device, int string_index, wchar_t *string, size_t maxlen);
388 
389 		/** @brief Get a string describing the last error which occurred.
390 
391 			@ingroup API
392 			@param device A device handle returned from hid_open().
393 
394 			@returns
395 				This function returns a string containing the last error
396 				which occurred or NULL if none has occurred.
397 		*/
398 		HID_API_EXPORT const wchar_t* HID_API_CALL hid_error(hid_device *device);
399 
400 #if defined(__cplusplus) && !defined(NAMESPACE)
401 }
402 #endif
403 #ifdef NAMESPACE
404 }
405 #endif
406 
407 #endif
408 
409