Fix rare deadlock when opening a HID controller on Android

Fixes https://github.com/libsdl-org/SDL/issues/6347
This commit is contained in:
Sam Lantinga 2022-10-06 18:23:07 -07:00
parent 689409fd97
commit fc720321b3
1 changed files with 52 additions and 8 deletions

View File

@ -330,8 +330,10 @@ HIDAPI_CleanupDeviceDriver(SDL_HIDAPI_Device *device)
}
static void
HIDAPI_SetupDeviceDriver(SDL_HIDAPI_Device *device)
HIDAPI_SetupDeviceDriver(SDL_HIDAPI_Device *device, SDL_bool *removed)
{
*removed = SDL_FALSE;
if (device->driver) {
SDL_bool enabled;
@ -359,14 +361,44 @@ HIDAPI_SetupDeviceDriver(SDL_HIDAPI_Device *device)
/* Make sure we can open the device and leave it open for the driver */
if (device->num_children == 0) {
device->dev = SDL_hid_open_path(device->path, 0);
if (!device->dev) {
/* On Android we need to leave joysticks unlocked because it calls
* out to the main thread for permissions and the main thread can
* be in the process of handling controller input.
*
* See https://github.com/libsdl-org/SDL/issues/6347 for details
*/
SDL_HIDAPI_Device *curr;
SDL_hid_device *dev;
char *path;
SDL_AssertJoysticksLocked();
path = SDL_strdup(device->path);
SDL_UnlockJoysticks();
dev = SDL_hid_open_path(path, 0);
SDL_LockJoysticks();
SDL_free(path);
/* Make sure the device didn't get removed while opening the HID path */
for (curr = SDL_HIDAPI_devices; curr && curr != device; curr = curr->next) {
continue;
}
if (!curr) {
*removed = SDL_TRUE;
if (dev) {
SDL_hid_close(dev);
}
return;
}
if (!dev) {
SDL_LogDebug(SDL_LOG_CATEGORY_INPUT,
"HIDAPI_SetupDeviceDriver() couldn't open %s: %s\n",
device->path, SDL_GetError());
return;
}
SDL_hid_set_nonblocking(device->dev, 1);
SDL_hid_set_nonblocking(dev, 1);
device->dev = dev;
}
device->driver = HIDAPI_GetDeviceDriver(device);
@ -388,6 +420,7 @@ SDL_HIDAPI_UpdateDrivers(void)
{
int i;
SDL_HIDAPI_Device *device;
SDL_bool removed;
SDL_HIDAPI_numdrivers = 0;
for (i = 0; i < SDL_arraysize(SDL_HIDAPI_drivers); ++i) {
@ -398,10 +431,16 @@ SDL_HIDAPI_UpdateDrivers(void)
}
}
removed = SDL_FALSE;
do {
for (device = SDL_HIDAPI_devices; device; device = device->next) {
HIDAPI_SetupDeviceDriver(device);
HIDAPI_SetupDeviceDriver(device, &removed);
if (removed) {
break;
}
}
} while (removed);
}
static void SDLCALL
SDL_HIDAPIDriverHintChanged(void *userdata, const char *name, const char *oldValue, const char *hint)
@ -685,6 +724,7 @@ HIDAPI_AddDevice(const struct SDL_hid_device_info *info, int num_children, SDL_H
{
SDL_HIDAPI_Device *device;
SDL_HIDAPI_Device *curr, *last = NULL;
SDL_bool removed;
for (curr = SDL_HIDAPI_devices, last = NULL; curr; last = curr, curr = curr->next) {
continue;
@ -762,7 +802,11 @@ HIDAPI_AddDevice(const struct SDL_hid_device_info *info, int num_children, SDL_H
SDL_HIDAPI_devices = device;
}
HIDAPI_SetupDeviceDriver(device);
removed = SDL_FALSE;
HIDAPI_SetupDeviceDriver(device, &removed);
if (removed) {
return NULL;
}
#ifdef DEBUG_HIDAPI
SDL_Log("Added HIDAPI device '%s' VID 0x%.4x, PID 0x%.4x, version %d, serial %s, interface %d, interface_class %d, interface_subclass %d, interface_protocol %d, usage page 0x%.4x, usage 0x%.4x, path = %s, driver = %s (%s)\n", device->name, device->vendor_id, device->product_id, device->version, device->serial ? device->serial : "NONE", device->interface_number, device->interface_class, device->interface_subclass, device->interface_protocol, device->usage_page, device->usage, device->path, device->driver ? device->driver->name : "NONE", device->driver && device->driver->enabled ? "ENABLED" : "DISABLED");