diff --git a/windows/hid.c b/windows/hid.c index ad6417a13..cb70ca0da 100644 --- a/windows/hid.c +++ b/windows/hid.c @@ -69,6 +69,15 @@ typedef LONG NTSTATUS; /* BLUETOOTH_DEVICE_NAME_SIZE from bluetoothapis.h is 256 */ #define MAX_STRING_WCHARS 256 +/* For certain USB devices, using a buffer larger or equal to 127 wchars results + in successful completion of HID API functions, but a broken string is stored + in the output buffer. This behaviour persists even if HID API is bypassed and + HID IOCTLs are passed to the HID driver directly. Therefore, for USB devices, + the buffer MUST NOT exceed 126 WCHARs. +*/ + +#define MAX_STRING_WCHARS_USB 126 + static struct hid_api_version api_version = { .major = HID_API_VERSION_MAJOR, .minor = HID_API_VERSION_MINOR, @@ -590,11 +599,22 @@ static void hid_internal_get_ble_info(struct hid_device_info* dev, DEVINST dev_n } } -static void hid_internal_get_info(const wchar_t* interface_path, struct hid_device_info* dev) +/* Unfortunately, HID_API_BUS_xxx constants alone aren't enough to distinguish between BLUETOOTH and BLE */ + +#define HID_API_BUS_FLAG_BLE 0x01 + +typedef struct hid_internal_detect_bus_type_result_ { + DEVINST dev_node; + hid_bus_type bus_type; + unsigned int bus_flags; +} hid_internal_detect_bus_type_result; + +static hid_internal_detect_bus_type_result hid_internal_detect_bus_type(const wchar_t* interface_path) { wchar_t *device_id = NULL, *compatible_ids = NULL; CONFIGRET cr; DEVINST dev_node; + hid_internal_detect_bus_type_result result = { 0 }; /* Get the device id from interface path */ device_id = hid_internal_get_device_interface_property(interface_path, &DEVPKEY_Device_InstanceId, DEVPROP_TYPE_STRING); @@ -625,42 +645,45 @@ static void hid_internal_get_info(const wchar_t* interface_path, struct hid_devi https://docs.microsoft.com/windows-hardware/drivers/hid/plug-and-play-support https://docs.microsoft.com/windows-hardware/drivers/install/standard-usb-identifiers */ if (wcsstr(compatible_id, L"USB") != NULL) { - dev->bus_type = HID_API_BUS_USB; - hid_internal_get_usb_info(dev, dev_node); + result.bus_type = HID_API_BUS_USB; break; } /* Bluetooth devices https://docs.microsoft.com/windows-hardware/drivers/bluetooth/installing-a-bluetooth-device */ if (wcsstr(compatible_id, L"BTHENUM") != NULL) { - dev->bus_type = HID_API_BUS_BLUETOOTH; + result.bus_type = HID_API_BUS_BLUETOOTH; break; } /* Bluetooth LE devices */ if (wcsstr(compatible_id, L"BTHLEDEVICE") != NULL) { - dev->bus_type = HID_API_BUS_BLUETOOTH; - hid_internal_get_ble_info(dev, dev_node); + result.bus_type = HID_API_BUS_BLUETOOTH; + result.bus_flags |= HID_API_BUS_FLAG_BLE; break; } /* I2C devices https://docs.microsoft.com/windows-hardware/drivers/hid/plug-and-play-support-and-power-management */ if (wcsstr(compatible_id, L"PNP0C50") != NULL) { - dev->bus_type = HID_API_BUS_I2C; + result.bus_type = HID_API_BUS_I2C; break; } /* SPI devices https://docs.microsoft.com/windows-hardware/drivers/hid/plug-and-play-for-spi */ if (wcsstr(compatible_id, L"PNP0C51") != NULL) { - dev->bus_type = HID_API_BUS_SPI; + result.bus_type = HID_API_BUS_SPI; break; } } + + result.dev_node = dev_node; + end: free(device_id); free(compatible_ids); + return result; } static char *hid_internal_UTF16toUTF8(const wchar_t *src) @@ -699,7 +722,10 @@ static struct hid_device_info *hid_internal_get_device_info(const wchar_t *path, HIDD_ATTRIBUTES attrib; PHIDP_PREPARSED_DATA pp_data = NULL; HIDP_CAPS caps; - wchar_t string[MAX_STRING_WCHARS]; + wchar_t string[MAX_STRING_WCHARS + 1]; + ULONG len; + ULONG size; + hid_internal_detect_bus_type_result detect_bus_type_result; /* Create the record. */ dev = (struct hid_device_info*)calloc(1, sizeof(struct hid_device_info)); @@ -733,25 +759,46 @@ static struct hid_device_info *hid_internal_get_device_info(const wchar_t *path, HidD_FreePreparsedData(pp_data); } + /* detect bus type before reading string descriptors */ + detect_bus_type_result = hid_internal_detect_bus_type(path); + dev->bus_type = detect_bus_type_result.bus_type; + + len = dev->bus_type == HID_API_BUS_USB ? MAX_STRING_WCHARS_USB : MAX_STRING_WCHARS; + string[len] = L'\0'; + size = len * sizeof(wchar_t); + /* Serial Number */ string[0] = L'\0'; - HidD_GetSerialNumberString(handle, string, sizeof(string)); - string[MAX_STRING_WCHARS - 1] = L'\0'; + HidD_GetSerialNumberString(handle, string, size); dev->serial_number = _wcsdup(string); /* Manufacturer String */ string[0] = L'\0'; - HidD_GetManufacturerString(handle, string, sizeof(string)); - string[MAX_STRING_WCHARS - 1] = L'\0'; + HidD_GetManufacturerString(handle, string, size); dev->manufacturer_string = _wcsdup(string); /* Product String */ string[0] = L'\0'; - HidD_GetProductString(handle, string, sizeof(string)); - string[MAX_STRING_WCHARS - 1] = L'\0'; + HidD_GetProductString(handle, string, size); dev->product_string = _wcsdup(string); - hid_internal_get_info(path, dev); + /* now, the portion that depends on string descriptors */ + switch (dev->bus_type) { + case HID_API_BUS_USB: + hid_internal_get_usb_info(dev, detect_bus_type_result.dev_node); + break; + + case HID_API_BUS_BLUETOOTH: + if (detect_bus_type_result.bus_flags & HID_API_BUS_FLAG_BLE) + hid_internal_get_ble_info(dev, detect_bus_type_result.dev_node); + break; + + case HID_API_BUS_UNKNOWN: + case HID_API_BUS_SPI: + case HID_API_BUS_I2C: + /* shut down -Wswitch */ + break; + } return dev; } @@ -1356,7 +1403,12 @@ int HID_API_EXPORT_CALL HID_API_CALL hid_get_indexed_string(hid_device *dev, int { BOOL res; - res = HidD_GetIndexedString(dev->device_handle, string_index, string, sizeof(wchar_t) * (DWORD) MIN(maxlen, MAX_STRING_WCHARS)); + if (dev->device_info && dev->device_info->bus_type == HID_API_BUS_USB && maxlen > MAX_STRING_WCHARS_USB) { + string[MAX_STRING_WCHARS_USB] = L'\0'; + maxlen = MAX_STRING_WCHARS_USB; + } + + res = HidD_GetIndexedString(dev->device_handle, string_index, string, (ULONG)maxlen * sizeof(wchar_t)); if (!res) { register_winapi_error(dev, L"HidD_GetIndexedString"); return -1;