SDL  2.0
hidapi.h
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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 */
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. */
84 
85  /** Additional information about the USB interface.
86  Valid on libusb and Android implementations. */
90 
91  /** Pointer to the next device */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
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  */
332 
333  /** @brief Close a HID device.
334 
335  @ingroup API
336  @param device A device handle returned from hid_open().
337  */
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  */
399 
400 #if defined(__cplusplus) && !defined(NAMESPACE)
401 }
402 #endif
403 #ifdef NAMESPACE
404 }
405 #endif
406 
407 #endif
408 
hid_device_info::interface_subclass
int interface_subclass
Definition: hidapi.h:88
hid_device_info::interface_number
int interface_number
Definition: hidapi.h:83
hid_write
int HID_API_EXPORT HID_API_CALL hid_write(hid_device *device, const unsigned char *data, size_t length)
Write an Output report to a HID device.
hid_send_feature_report
int HID_API_EXPORT HID_API_CALL hid_send_feature_report(hid_device *device, const unsigned char *data, size_t length)
Send a Feature report to the device.
hid_exit
int HID_API_EXPORT HID_API_CALL hid_exit(void)
Finalize the HIDAPI library.
hid_close
void HID_API_EXPORT HID_API_CALL hid_close(hid_device *device)
Close a HID device.
hid_free_enumeration
void HID_API_EXPORT HID_API_CALL hid_free_enumeration(struct hid_device_info *devs)
Free an enumeration Linked List.
hid_init
int HID_API_EXPORT HID_API_CALL hid_init(void)
Initialize the HIDAPI library.
HID_API_EXPORT_CALL
#define HID_API_EXPORT_CALL
Definition: hidapi.h:44
hid_get_indexed_string
int HID_API_EXPORT_CALL hid_get_indexed_string(hid_device *device, int string_index, wchar_t *string, size_t maxlen)
Get a string from a HID device, based on its string index.
path
GLsizei const GLchar *const * path
Definition: SDL_opengl_glext.h:3733
hid_device_info::manufacturer_string
wchar_t * manufacturer_string
Definition: hidapi.h:70
length
GLuint GLsizei GLsizei * length
Definition: SDL_opengl_glext.h:672
hid_open
HID_API_EXPORT hid_device *HID_API_CALL hid_open(unsigned short vendor_id, unsigned short product_id, const wchar_t *serial_number)
Open a HID device using a Vendor ID (VID), Product ID (PID) and optionally a serial number.
data
GLint GLenum GLsizei GLsizei GLsizei GLint GLsizei const GLvoid * data
Definition: SDL_opengl.h:1974
hid_device_info::next
struct hid_device_info * next
Definition: hidapi.h:92
hid_device_info
Definition: hidapi.h:57
hid_enumerate
struct hid_device_info HID_API_EXPORT *HID_API_CALL hid_enumerate(unsigned short vendor_id, unsigned short product_id)
Enumerate the HID Devices.
hid_device_info::product_id
unsigned short product_id
Definition: hidapi.h:63
hid_read_timeout
int HID_API_EXPORT HID_API_CALL hid_read_timeout(hid_device *device, unsigned char *data, size_t length, int milliseconds)
Read an Input report from a HID device with timeout.
hid_device_info::interface_class
int interface_class
Definition: hidapi.h:87
hid_device_info::serial_number
wchar_t * serial_number
Definition: hidapi.h:65
hid_device_info::release_number
unsigned short release_number
Definition: hidapi.h:68
hid_open_path
HID_API_EXPORT hid_device *HID_API_CALL hid_open_path(const char *path, int bExclusive)
Open a HID device by its path name.
hid_device_info::usage
unsigned short usage
Definition: hidapi.h:78
hid_device_info::interface_protocol
int interface_protocol
Definition: hidapi.h:89
hid_get_serial_number_string
int HID_API_EXPORT_CALL hid_get_serial_number_string(hid_device *device, wchar_t *string, size_t maxlen)
Get The Serial Number String from a HID device.
HID_API_CALL
#define HID_API_CALL
Definition: hidapi.h:40
hid_device_info::usage_page
unsigned short usage_page
Definition: hidapi.h:75
hid_get_feature_report
int HID_API_EXPORT HID_API_CALL hid_get_feature_report(hid_device *device, unsigned char *data, size_t length)
Get a feature report from a HID device.
hid_error
HID_API_EXPORT const wchar_t *HID_API_CALL hid_error(hid_device *device)
Get a string describing the last error which occurred.
hid_set_nonblocking
int HID_API_EXPORT HID_API_CALL hid_set_nonblocking(hid_device *device, int nonblock)
Set the device handle to be non-blocking.
hid_read
int HID_API_EXPORT HID_API_CALL hid_read(hid_device *device, unsigned char *data, size_t length)
Read an Input report from a HID device.
hid_get_product_string
int HID_API_EXPORT_CALL hid_get_product_string(hid_device *device, wchar_t *string, size_t maxlen)
Get The Product String from a HID device.
hid_device
struct hid_device_ hid_device
Definition: hidapi.h:54
NAMESPACE
#define NAMESPACE
Definition: hidusb.cpp:2
hid_device_info::path
char * path
Definition: hidapi.h:59
device
static SDL_AudioDeviceID device
Definition: loopwave.c:37
hid_get_manufacturer_string
int HID_API_EXPORT_CALL hid_get_manufacturer_string(hid_device *device, wchar_t *string, size_t maxlen)
Get The Manufacturer String from a HID device.
hid_device_info::vendor_id
unsigned short vendor_id
Definition: hidapi.h:61
hid_device_info::product_string
wchar_t * product_string
Definition: hidapi.h:72
HID_API_EXPORT
#define HID_API_EXPORT
Definition: hidapi.h:37