Merge pull request #102 from mogenson/libusb_package

Load libusb-1.0 shared library from libusb_package wheel

apps/usb_probe.py

@@ -31,6 +31,7 @@ import logging
 import sys
 import click
 import usb1
+from bumble.transport.usb import load_libusb
 from colors import color
 
 
@@ -169,6 +170,7 @@ def is_bluetooth_hci(device):
 def main(verbose):
     logging.basicConfig(level=os.environ.get('BUMBLE_LOGLEVEL', 'WARNING').upper())
 
+    load_libusb()
     with usb1.USBContext() as context:
         bluetooth_device_count = 0
         devices = {}

bumble/transport/pyusb.py

@@ -17,6 +17,7 @@
 # -----------------------------------------------------------------------------
 import asyncio
 import logging
+import libusb_package
 import usb.core
 import usb.util
 import threading
@@ -203,13 +204,13 @@ async def open_pyusb_transport(spec):
     # Find the device according to the spec moniker
     if ':' in spec:
         vendor_id, product_id = spec.split(':')
-        device = usb.core.find(
+        device = libusb_package.find(
             idVendor=int(vendor_id, 16), idProduct=int(product_id, 16)
         )
     else:
         device_index = int(spec)
         devices = list(
-            usb.core.find(
+            libusb_package.find(
                 find_all=1,
                 bDeviceClass=USB_DEVICE_CLASS_WIRELESS_CONTROLLER,
                 bDeviceSubClass=USB_DEVICE_SUBCLASS_RF_CONTROLLER,

bumble/transport/usb.py

@@ -17,9 +17,12 @@
 # -----------------------------------------------------------------------------
 import asyncio
 import logging
+import libusb_package
 import usb1
 import threading
 import collections
+import ctypes
+import platform
 from colors import color
 
 from .common import Transport, ParserSource
@@ -33,6 +36,19 @@ logger = logging.getLogger(__name__)
 
 
 # -----------------------------------------------------------------------------
+def load_libusb():
+    '''
+    Attempt to load the libusb-1.0 C library from libusb_package in site-packages.
+    If library exists, we create a DLL object and initialize the usb1 backend.
+    This only needs to be done once, but bufore a usb1.USBContext is created.
+    If library does not exists, do nothing and usb1 will search default system paths
+    when usb1.USBContext is created.
+    '''
+    if libusb_path := libusb_package.get_library_path():
+        dll_loader = ctypes.WinDLL if platform.system() == 'Windows' else ctypes.CDLL
+        libusb_dll = dll_loader(libusb_path, use_errno=True, use_last_error=True)
+        usb1.loadLibrary(libusb_dll)
+
 async def open_usb_transport(spec):
     '''
     Open a USB transport.
@@ -305,6 +321,7 @@ async def open_usb_transport(spec):
             self.context.close()
 
     # Find the device according to the spec moniker
+    load_libusb()
     context = usb1.USBContext()
     context.open()
     try:

docs/mkdocs/src/transports/usb.md

@@ -42,6 +42,11 @@ This may be useful for some devices that use a custom class/subclass but may non
 The library includes two different implementations of the USB transport, implemented using different python bindings for `libusb`.
 Using the transport prefix `pyusb:` instead of `usb:` selects the implementation based on  [PyUSB](https://pypi.org/project/pyusb/), using the synchronous API of `libusb`, whereas the default implementation is based on [libusb1](https://pypi.org/project/libusb1/), using the asynchronous API of `libusb`. In order to use the alternative PyUSB-based implementation, you need to ensure that you have installed that python module, as it isn't installed by default as a dependency of Bumble.
 
+## Libusb
+
+The `libusb-1.0` shared library is required to use both `usb` and `pyusb` transports. This library should be installed automatically with Bumble, as part of the `libusb_package` Python package.
+If your OS or architecture is not supported by `libusb_package`, you can install a system-wide library with `brew install libusb` for Mac or `apt install libusb-1.0-0` for Linux.
+
 ## Listing Available USB Devices
 
 ### With `usb_probe`

setup.cfg

@@ -37,6 +37,7 @@ install_requires =
     cryptography == 35; platform_system!='Emscripten'
     grpcio >= 1.46; platform_system!='Emscripten'
     libusb1 >= 2.0.1; platform_system!='Emscripten'
+    libusb-package == 1.0.26.0; platform_system!='Emscripten'
     prompt_toolkit >= 3.0.16; platform_system!='Emscripten'
     protobuf >= 3.12.4
     pyee >= 8.2.2