From 57b33aec01a86c28b30797ecbae394a2f07ddd42 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Thu, 25 May 2023 12:43:09 -0700
Subject: [PATCH] hidapi/libusb: allow building on Windows, using the SDL C
runtime
Signed-off-by: Sam Lantinga <slouken@libsdl.org>
---
src/hidapi/SDL_hidapi_libusb.h | 202 +++++++++++++++++++++++++++++++++
src/hidapi/libusb/hid.c | 200 ++++++++++++++++++++++----------
2 files changed, 344 insertions(+), 58 deletions(-)
diff --git a/src/hidapi/SDL_hidapi_libusb.h b/src/hidapi/SDL_hidapi_libusb.h
index ead421ba06cc..e0a124833834 100644
--- a/src/hidapi/SDL_hidapi_libusb.h
+++ b/src/hidapi/SDL_hidapi_libusb.h
@@ -19,6 +19,28 @@
3. This notice may not be removed or altered from any source distribution.
*/
+/* Define standard library functions in terms of SDL */
+#define HIDAPI_USING_SDL_RUNTIME
+#define free SDL_free
+#define iconv_t SDL_iconv_t
+#define ICONV_CONST
+#define iconv(a,b,c,d,e) SDL_iconv(a, (const char **)b, c, d, e)
+#define iconv_open SDL_iconv_open
+#define iconv_close SDL_iconv_close
+#define malloc SDL_malloc
+#define realloc SDL_realloc
+#define setlocale(X, Y) NULL
+#define snprintf SDL_snprintf
+#define strcmp SDL_strcmp
+#define strdup SDL_strdup
+#define strncpy SDL_strlcpy
+#ifdef tolower
+#undef tolower
+#endif
+#define tolower SDL_tolower
+#define wcsdup SDL_wcsdup
+
+
#ifndef __FreeBSD__
/* this is awkwardly inlined, so we need to re-implement it here
* so we can override the libusb_control_transfer call */
@@ -32,5 +54,185 @@ static int SDL_libusb_get_string_descriptor(libusb_device_handle *dev,
#define libusb_get_string_descriptor SDL_libusb_get_string_descriptor
#endif /* __FreeBSD__ */
+#define HIDAPI_THREAD_STATE_DEFINED
+
+/* Barrier implementation because Android/Bionic don't have pthread_barrier.
+ This implementation came from Brent Priddy and was posted on
+ StackOverflow. It is used with his permission. */
+
+typedef struct _SDL_ThreadBarrier
+{
+ SDL_Mutex *mutex;
+ SDL_Condition *cond;
+ Uint32 count;
+ Uint32 trip_count;
+} SDL_ThreadBarrier;
+
+static int SDL_CreateThreadBarrier(SDL_ThreadBarrier *barrier, Uint32 count)
+{
+ SDL_assert(barrier != NULL);
+ SDL_assert(count != 0);
+
+ barrier->mutex = SDL_CreateMutex();
+ if (barrier->mutex == NULL) {
+ return -1; /* Error set by CreateMutex */
+ }
+ barrier->cond = SDL_CreateCondition();
+ if (barrier->cond == NULL) {
+ return -1; /* Error set by CreateCond */
+ }
+
+ barrier->trip_count = count;
+ barrier->count = 0;
+
+ return 0;
+}
+
+static void SDL_DestroyThreadBarrier(SDL_ThreadBarrier *barrier)
+{
+ SDL_DestroyCondition(barrier->cond);
+ SDL_DestroyMutex(barrier->mutex);
+}
+
+static int SDL_WaitThreadBarrier(SDL_ThreadBarrier *barrier)
+{
+ SDL_LockMutex(barrier->mutex);
+ barrier->count += 1;
+ if (barrier->count >= barrier->trip_count) {
+ barrier->count = 0;
+ SDL_BroadcastCondition(barrier->cond);
+ SDL_UnlockMutex(barrier->mutex);
+ return 1;
+ }
+ SDL_WaitCondition(barrier->cond, barrier->mutex);
+ SDL_UnlockMutex(barrier->mutex);
+ return 0;
+}
+
+#include "../thread/SDL_systhread.h"
+
+#define THREAD_STATE_WAIT_TIMED_OUT SDL_MUTEX_TIMEDOUT
+
+typedef struct
+{
+ SDL_Thread *thread;
+ SDL_Mutex *mutex; /* Protects input_reports */
+ SDL_Condition *condition;
+ SDL_ThreadBarrier barrier; /* Ensures correct startup sequence */
+
+} hid_device_thread_state;
+
+static void thread_state_init(hid_device_thread_state *state)
+{
+ state->mutex = SDL_CreateMutex();
+ state->condition = SDL_CreateCondition();
+ SDL_CreateThreadBarrier(&state->barrier, 2);
+}
+
+static void thread_state_free(hid_device_thread_state *state)
+{
+ SDL_DestroyThreadBarrier(&state->barrier);
+ SDL_DestroyCondition(state->condition);
+ SDL_DestroyMutex(state->mutex);
+}
+
+static void thread_state_push_cleanup(void (*routine)(void *), void *arg)
+{
+ /* There isn't an equivalent in SDL, and it's only useful for threads calling hid_read_timeout() */
+}
+
+static void thread_state_pop_cleanup(int execute)
+{
+}
+
+static void thread_state_lock(hid_device_thread_state *state)
+{
+ SDL_LockMutex(state->mutex);
+}
+
+static void thread_state_unlock(hid_device_thread_state *state)
+{
+ SDL_UnlockMutex(state->mutex);
+}
+
+static void thread_state_wait_condition(hid_device_thread_state *state)
+{
+ SDL_WaitCondition(state->condition, state->mutex);
+}
+
+static int thread_state_wait_condition_timeout(hid_device_thread_state *state, struct timespec *ts)
+{
+ Uint64 end_time;
+ Sint64 timeout_ns;
+ Sint32 timeout_ms;
+
+ end_time = ts->tv_sec;
+ end_time *= 1000000000L;
+ end_time += ts->tv_nsec;
+ timeout_ns = (Sint64)(end_time - SDL_GetTicksNS());
+ if (timeout_ns <= 0) {
+ timeout_ms = 0;
+ } else {
+ timeout_ms = (Sint32)SDL_NS_TO_MS(timeout_ns);
+ }
+ return SDL_WaitConditionTimeout(state->condition, state->mutex, timeout_ms);
+}
+
+static void thread_state_signal_condition(hid_device_thread_state *state)
+{
+ SDL_SignalCondition(state->condition);
+}
+
+static void thread_state_broadcast_condition(hid_device_thread_state *state)
+{
+ SDL_BroadcastCondition(state->condition);
+}
+
+static void thread_state_wait_barrier(hid_device_thread_state *state)
+{
+ SDL_WaitThreadBarrier(&state->barrier);
+}
+
+typedef struct
+{
+ void *(*func)(void*);
+ void *func_arg;
+
+} RunInputThreadParam;
+
+static int RunInputThread(void *param)
+{
+ RunInputThreadParam *data = (RunInputThreadParam *)param;
+ void *(*func)(void*) = data->func;
+ void *func_arg = data->func_arg;
+ SDL_free(data);
+ func(func_arg);
+ return 0;
+}
+
+static void thread_state_create_thread(hid_device_thread_state *state, void *(*func)(void*), void *func_arg)
+{
+ RunInputThreadParam *param = (RunInputThreadParam *)malloc(sizeof(*param));
+ /* Note that the hidapi code didn't check for thread creation failure.
+ * We'll crash if malloc() fails
+ */
+ param->func = func;
+ param->func_arg = func_arg;
+ state->thread = SDL_CreateThreadInternal(RunInputThread, "libusb", 0, param);
+}
+
+static void thread_state_join_thread(hid_device_thread_state *state)
+{
+ SDL_WaitThread(state->thread, NULL);
+}
+
+static void thread_state_get_current_time(struct timespec *ts)
+{
+ Uint64 ns = SDL_GetTicksNS();
+
+ ts->tv_sec = ns / 1000000000L;
+ ts->tv_nsec = ns % 1000000000L;
+}
+
#undef HIDAPI_H__
#include "libusb/hid.c"
diff --git a/src/hidapi/libusb/hid.c b/src/hidapi/libusb/hid.c
index 05b393f65176..47a3e3e1bf3f 100644
--- a/src/hidapi/libusb/hid.c
+++ b/src/hidapi/libusb/hid.c
@@ -20,6 +20,7 @@
https://github.com/libusb/hidapi .
********************************************************/
+#ifndef HIDAPI_USING_SDL_RUNTIME
#define _GNU_SOURCE /* needed for wcsdup() before glibc 2.10 */
/* C */
@@ -37,7 +38,6 @@
#include <sys/ioctl.h>
#include <sys/utsname.h>
#include <fcntl.h>
-#include <pthread.h>
#include <wchar.h>
/* GNU / LibUSB */
@@ -48,9 +48,43 @@
#define ICONV_CONST
#endif
#endif
+#endif /* HIDAPI_USING_SDL_RUNTIME */
#include "hidapi_libusb.h"
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef DEBUG_PRINTF
+#define LOG(...) fprintf(stderr, __VA_ARGS__)
+#else
+#define LOG(...) do {} while (0)
+#endif
+
+#ifndef __FreeBSD__
+#define DETACH_KERNEL_DRIVER
+#endif
+
+/* Uncomment to enable the retrieval of Usage and Usage Page in
+hid_enumerate(). Warning, on platforms different from FreeBSD
+this is very invasive as it requires the detach
+and re-attach of the kernel driver. See comments inside hid_enumerate().
+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;
+};
+
+#ifndef HIDAPI_THREAD_STATE_DEFINED
+
+#include <pthread.h>
+
#if defined(__ANDROID__) && __ANDROID_API__ < __ANDROID_API_N__
/* Barrier implementation because Android/Bionic don't have pthread_barrier.
@@ -112,35 +146,92 @@ static int pthread_barrier_wait(pthread_barrier_t *barrier)
#endif
-#ifdef __cplusplus
-extern "C" {
-#endif
+#define THREAD_STATE_WAIT_TIMED_OUT ETIMEDOUT
-#ifdef DEBUG_PRINTF
-#define LOG(...) fprintf(stderr, __VA_ARGS__)
-#else
-#define LOG(...) do {} while (0)
-#endif
+typdef struct
+{
+ pthread_t thread;
+ pthread_mutex_t mutex; /* Protects input_reports */
+ pthread_cond_t condition;
+ pthread_barrier_t barrier; /* Ensures correct startup sequence */
-#ifndef __FreeBSD__
-#define DETACH_KERNEL_DRIVER
-#endif
+} hid_device_thread_state;
-/* Uncomment to enable the retrieval of Usage and Usage Page in
-hid_enumerate(). Warning, on platforms different from FreeBSD
-this is very invasive as it requires the detach
-and re-attach of the kernel driver. See comments inside hid_enumerate().
-libusb HIDAPI programs are encouraged to use the interface number
-instead to differentiate between interfaces on a composite HID device. */
-/*#define INVASIVE_GET_USAGE*/
+static void thread_state_init(hid_device_thread_state *state)
+{
+ pthread_mutex_init(&state->mutex, NULL);
+ pthread_cond_init(&state->condition, NULL);
+ pthread_barrier_init(&state->barrier, NULL, 2);
+}
-/* Linked List of input reports received from the device. */
-struct input_report {
- uint8_t *data;
- size_t len;
- struct input_report *next;
-};
+static void thread_state_free(hid_device_thread_state *state)
+{
+ pthread_barrier_destroy(&state->barrier);
+ pthread_cond_destroy(&state->condition);
+ pthread_mutex_destroy(&state->mutex);
+}
+
+static void thread_state_push_cleanup(void (*routine)(void *), void *arg)
+{
+ pthread_cleanup_push(&cleanup_mutex, dev);
+}
+
+static void thread_state_pop_cleanup(int execute)
+{
+ pthread_cleanup_pop(execute);
+}
+
+static void thread_state_lock(hid_device_thread_state *state)
+{
+ pthread_mutex_lock(&state->mutex);
+}
+
+static void thread_state_unlock(hid_device_thread_state *state)
+{
+ pthread_mutex_unlock(&state->mutex);
+}
+
+static void thread_state_wait_condition(hid_device_thread_state *state)
+{
+ pthread_cond_wait(&state->condition, &state->mutex);
+}
+
+static int thread_state_wait_condition_timeout(hid_device_thread_state *state, struct timespec *ts)
+{
+ return pthread_cond_timedwait(&state->condition, &state->mutex, ts);
+}
+
+static void thread_state_signal_condition(hid_device_thread_state *state)
+{
+ pthread_cond_signal(&state->condition);
+}
+static void thread_state_broadcast_condition(hid_device_thread_state *state)
+{
+ pthread_cond_broadcast(&state->condition);
+}
+
+static void thread_state_wait_barrier(hid_device_thread_state *state)
+{
+ pthread_barrier_wait(&state->barrier);
+}
+
+static void thread_state_create_thread(hid_device_thread_state *state, void *(*func)(void*), void *func_arg)
+{
+ pthread_create(&dev->thread, NULL, func, param);
+}
+
+static void thread_state_join_thread(hid_device_thread_state *state)
+{
+ pthread_join(state->thread, NULL);
+}
+
+static void thread_state_get_current_time(struct timespec *ts)
+{
+ clock_gettime(CLOCK_REALTIME, ts);
+}
+
+#endif /* !HIDAPI_THREAD_STATE_DEFINED */
struct hid_device_ {
/* Handle to the actual device. */
@@ -171,10 +262,7 @@ struct hid_device_ {
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 */
+ hid_device_thread_state thread_state;
int shutdown_thread;
int transfer_loop_finished;
struct libusb_transfer *transfer;
@@ -208,9 +296,7 @@ static hid_device *new_hid_device(void)
hid_device *dev = (hid_device*) calloc(1, sizeof(hid_device));
dev->blocking = 1;
- pthread_mutex_init(&dev->mutex, NULL);
- pthread_cond_init(&dev->condition, NULL);
- pthread_barrier_init(&dev->barrier, NULL, 2);
+ thread_state_init(&dev->thread_state);
return dev;
}
@@ -218,9 +304,7 @@ static hid_device *new_hid_device(void)
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);
+ thread_state_free(&dev->thread_state);
hid_free_enumeration(dev->device_info);
@@ -1143,13 +1227,13 @@ static void LIBUSB_CALL read_callback(struct libusb_transfer *transfer)
rpt->len = transfer->actual_length;
rpt->next = NULL;
- pthread_mutex_lock(&dev->mutex);
+ thread_state_lock(&dev->thread_state);
/* 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);
+ thread_state_signal_condition(&dev->thread_state);
}
else {
/* Find the end of the list and attach. */
@@ -1168,7 +1252,7 @@ static void LIBUSB_CALL read_callback(struct libusb_transfer *transfer)
return_data(dev, NULL, 0);
}
}
- pthread_mutex_unlock(&dev->mutex);
+ thread_state_unlock(&dev->thread_state);
}
else if (transfer->status == LIBUSB_TRANSFER_CANCELLED) {
dev->shutdown_thread = 1;
@@ -1227,7 +1311,7 @@ static void *read_thread(void *param)
}
/* Notify the main thread that the read thread is up and running. */
- pthread_barrier_wait(&dev->barrier);
+ thread_state_wait_barrier(&dev->thread_state);
/* Handle all the events. */
while (!dev->shutdown_thread) {
@@ -1259,15 +1343,15 @@ static void *read_thread(void *param)
make sure that a thread which is about to go to sleep waiting on
the condition actually will go to sleep before the condition is
signaled. */
- pthread_mutex_lock(&dev->mutex);
- pthread_cond_broadcast(&dev->condition);
- pthread_mutex_unlock(&dev->mutex);
+ thread_state_lock(&dev->thread_state);
+ thread_state_broadcast_condition(&dev->thread_state);
+ thread_state_unlock(&dev->thread_state);
/* 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
+ cleaned up after the call to thread_state_join() (in hid_close()), but
since hid_close() calls libusb_cancel_transfer(), on these objects,
they can not be cleaned up here. */
@@ -1445,15 +1529,15 @@ static int hidapi_initialize_device(hid_device *dev, int config_number, const st
calculate_device_quirks(dev, desc.idVendor, desc.idProduct);
- pthread_create(&dev->thread, NULL, read_thread, dev);
+ thread_state_create_thread(&dev->thread_state, read_thread, dev);
/* Wait here for the read thread to be initialized. */
- pthread_barrier_wait(&dev->barrier);
+ thread_state_wait_barrier(&dev->thread_state);
return 1;
}
-hid_device * HID_API_EXPORT hid_open_path(const char *path)
+HID_API_EXPORT hid_device *hid_open_path(const char *path)
{
hid_device *dev = NULL;
@@ -1673,7 +1757,7 @@ static int return_data(hid_device *dev, unsigned char *data, size_t length)
static void cleanup_mutex(void *param)
{
hid_device *dev = param;
- pthread_mutex_unlock(&dev->mutex);
+ thread_state_unlock(&dev->thread_state);
}
@@ -1689,8 +1773,8 @@ int HID_API_EXPORT hid_read_timeout(hid_device *dev, unsigned char *data, size_t
/* error: variable ‘bytes_read’ might be clobbered by ‘longjmp’ or ‘vfork’ [-Werror=clobbered] */
int bytes_read; /* = -1; */
- pthread_mutex_lock(&dev->mutex);
- pthread_cleanup_push(&cleanup_mutex, dev);
+ thread_state_lock(&dev->thread_state);
+ thread_state_push_cleanup(cleanup_mutex, dev);
bytes_read = -1;
@@ -1711,7 +1795,7 @@ int HID_API_EXPORT hid_read_timeout(hid_device *dev, unsigned char *data, size_t
if (milliseconds == -1) {
/* Blocking */
while (!dev->input_reports && !dev->shutdown_thread) {
- pthread_cond_wait(&dev->condition, &dev->mutex);
+ thread_state_wait_condition(&dev->thread_state);
}
if (dev->input_reports) {
bytes_read = return_data(dev, data, length);
@@ -1721,7 +1805,7 @@ int HID_API_EXPORT hid_read_timeout(hid_device *dev, unsigned char *data, size_t
/* Non-blocking, but called with timeout. */
int res;
struct timespec ts;
- clock_gettime(CLOCK_REALTIME, &ts);
+ thread_state_get_current_time(&ts);
ts.tv_sec += milliseconds / 1000;
ts.tv_nsec += (milliseconds % 1000) * 1000000;
if (ts.tv_nsec >= 1000000000L) {
@@ -1730,7 +1814,7 @@ int HID_API_EXPORT hid_read_timeout(hid_device *dev, unsigned char *data, size_t
}
while (!dev->input_reports && !dev->shutdown_thread) {
- res = pthread_cond_timedwait(&dev->condition, &dev->mutex, &ts);
+ res = thread_state_wait_condition_timeout(&dev->thread_state, &ts);
if (res == 0) {
if (dev->input_reports) {
bytes_read = return_data(dev, data, length);
@@ -1741,7 +1825,7 @@ int HID_API_EXPORT hid_read_timeout(hid_device *dev, unsigned char *data, size_t
or the read thread was shutdown. Run the
loop again (ie: don't break). */
}
- else if (res == ETIMEDOUT) {
+ else if (res == THREAD_STATE_WAIT_TIMED_OUT) {
/* Timed out. */
bytes_read = 0;
break;
@@ -1759,8 +1843,8 @@ int HID_API_EXPORT hid_read_timeout(hid_device *dev, unsigned char *data, size_t
}
ret:
- pthread_mutex_unlock(&dev->mutex);
- pthread_cleanup_pop(0);
+ thread_state_unlock(&dev->thread_state);
+ thread_state_pop_cleanup(0);
return bytes_read;
}
@@ -1878,7 +1962,7 @@ void HID_API_EXPORT hid_close(hid_device *dev)
libusb_cancel_transfer(dev->transfer);
/* Wait for read_thread() to end. */
- pthread_join(dev->thread, NULL);
+ thread_state_join_thread(&dev->thread_state);
/* Clean up the Transfer objects allocated in read_thread(). */
free(dev->transfer->buffer);
@@ -1901,11 +1985,11 @@ void HID_API_EXPORT hid_close(hid_device *dev)
libusb_close(dev->device_handle);
/* Clear out the queue of received reports. */
- pthread_mutex_lock(&dev->mutex);
+ thread_state_lock(&dev->thread_state);
while (dev->input_reports) {
return_data(dev, NULL, 0);
}
- pthread_mutex_unlock(&dev->mutex);
+ thread_state_unlock(&dev->thread_state);
free_hid_device(dev);
}