Merge pull request #364 from torque/macos-usb-product-descriptor-fix

macOS: rework list_ports to support unicode product descriptors.

1 files changed, 55 insertions, 22 deletions

diff --git a/serial/tools/list_ports_osx.py b/serial/tools/list_ports_osx.py
index f46a820..34a7f5a 100644
--- a/serial/tools/list_ports_osx.py
+++ b/serial/tools/list_ports_osx.py
@@ -35,25 +35,40 @@ kIOMasterPortDefault = ctypes.c_void_p.in_dll(iokit, "kIOMasterPortDefault")
 kCFAllocatorDefault = ctypes.c_void_p.in_dll(cf, "kCFAllocatorDefault")
 
 kCFStringEncodingMacRoman = 0
+kCFStringEncodingUTF8 = 0x08000100
+
+# defined in `IOKit/usb/USBSpec.h`
+kUSBVendorString = 'USB Vendor Name'
+kUSBSerialNumberString = 'USB Serial Number'
+
+# `io_name_t` defined as `typedef char io_name_t[128];`
+# in `device/device_types.h`
+io_name_size = 128
+
+# defined in `mach/kern_return.h`
+KERN_SUCCESS = 0
+# kern_return_t defined as `typedef int kern_return_t;` in `mach/i386/kern_return.h`
+kern_return_t = ctypes.c_int
 
 iokit.IOServiceMatching.restype = ctypes.c_void_p
 
 iokit.IOServiceGetMatchingServices.argtypes = [ctypes.c_void_p, ctypes.c_void_p, ctypes.c_void_p]
-iokit.IOServiceGetMatchingServices.restype = ctypes.c_void_p
+iokit.IOServiceGetMatchingServices.restype = kern_return_t
 
 iokit.IORegistryEntryGetParentEntry.argtypes = [ctypes.c_void_p, ctypes.c_void_p, ctypes.c_void_p]
+iokit.IOServiceGetMatchingServices.restype = kern_return_t
 
 iokit.IORegistryEntryCreateCFProperty.argtypes = [ctypes.c_void_p, ctypes.c_void_p, ctypes.c_void_p, ctypes.c_uint32]
 iokit.IORegistryEntryCreateCFProperty.restype = ctypes.c_void_p
 
 iokit.IORegistryEntryGetPath.argtypes = [ctypes.c_void_p, ctypes.c_void_p, ctypes.c_void_p]
-iokit.IORegistryEntryGetPath.restype = ctypes.c_void_p
+iokit.IORegistryEntryGetPath.restype = kern_return_t
 
 iokit.IORegistryEntryGetName.argtypes = [ctypes.c_void_p, ctypes.c_void_p]
-iokit.IORegistryEntryGetName.restype = ctypes.c_void_p
+iokit.IORegistryEntryGetName.restype = kern_return_t
 
 iokit.IOObjectGetClass.argtypes = [ctypes.c_void_p, ctypes.c_void_p]
-iokit.IOObjectGetClass.restype = ctypes.c_void_p
+iokit.IOObjectGetClass.restype = kern_return_t
 
 iokit.IOObjectRelease.argtypes = [ctypes.c_void_p]
 
@@ -64,6 +79,9 @@ cf.CFStringCreateWithCString.restype = ctypes.c_void_p
 cf.CFStringGetCStringPtr.argtypes = [ctypes.c_void_p, ctypes.c_uint32]
 cf.CFStringGetCStringPtr.restype = ctypes.c_char_p
 
+cf.CFStringGetCString.argtypes = [ctypes.c_void_p, ctypes.c_void_p, ctypes.c_long, ctypes.c_uint32]
+cf.CFStringGetCString.restype = ctypes.c_bool
+
 cf.CFNumberGetValue.argtypes = [ctypes.c_void_p, ctypes.c_uint32, ctypes.c_void_p]
 cf.CFNumberGetValue.restype = ctypes.c_void_p
 
@@ -88,8 +106,8 @@ def get_string_property(device_type, property):
     """
     key = cf.CFStringCreateWithCString(
             kCFAllocatorDefault,
-            property.encode("mac_roman"),
-            kCFStringEncodingMacRoman)
+            property.encode("utf-8"),
+            kCFStringEncodingUTF8)
 
     CFContainer = iokit.IORegistryEntryCreateCFProperty(
             device_type,
@@ -101,7 +119,12 @@ def get_string_property(device_type, property):
     if CFContainer:
         output = cf.CFStringGetCStringPtr(CFContainer, 0)
         if output is not None:
-            output = output.decode('mac_roman')
+            output = output.decode('utf-8')
+        else:
+            buffer = ctypes.create_string_buffer(io_name_size);
+            success = cf.CFStringGetCString(CFContainer, ctypes.byref(buffer), io_name_size, kCFStringEncodingUTF8)
+            if success:
+                output = buffer.value.decode('utf-8')
         cf.CFRelease(CFContainer)
     return output
 
@@ -118,8 +141,8 @@ def get_int_property(device_type, property, cf_number_type):
     """
     key = cf.CFStringCreateWithCString(
             kCFAllocatorDefault,
-            property.encode("mac_roman"),
-            kCFStringEncodingMacRoman)
+            property.encode("utf-8"),
+            kCFStringEncodingUTF8)
 
     CFContainer = iokit.IORegistryEntryCreateCFProperty(
             device_type,
@@ -137,12 +160,19 @@ def get_int_property(device_type, property, cf_number_type):
         return number.value
     return None
 
-
 def IORegistryEntryGetName(device):
-    pathname = ctypes.create_string_buffer(100)  # TODO: Is this ok?
-    iokit.IOObjectGetClass(device, ctypes.byref(pathname))
-    return pathname.value
-
+    devicename = ctypes.create_string_buffer(io_name_size);
+    res = iokit.IORegistryEntryGetName(device, ctypes.byref(devicename))
+    if res != KERN_SUCCESS:
+        return None
+    # this works in python2 but may not be valid. Also I don't know if
+    # this encoding is guaranteed. It may be dependent on system locale.
+    return devicename.value.decode('utf-8')
+
+def IOObjectGetClass(device):
+    classname = ctypes.create_string_buffer(io_name_size)
+    iokit.IOObjectGetClass(device, ctypes.byref(classname))
+    return classname.value
 
 def GetParentDeviceByType(device, parent_type):
     """ Find the first parent of a device that implements the parent_type
@@ -150,15 +180,15 @@ def GetParentDeviceByType(device, parent_type):
         @return Pointer to the parent type, or None if it was not found.
     """
     # First, try to walk up the IOService tree to find a parent of this device that is a IOUSBDevice.
-    parent_type = parent_type.encode('mac_roman')
-    while IORegistryEntryGetName(device) != parent_type:
+    parent_type = parent_type.encode('utf-8')
+    while IOObjectGetClass(device) != parent_type:
         parent = ctypes.c_void_p()
         response = iokit.IORegistryEntryGetParentEntry(
                 device,
-                "IOService".encode("mac_roman"),
+                "IOService".encode("utf-8"),
                 ctypes.byref(parent))
         # If we weren't able to find a parent for the device, we're done.
-        if response != 0:
+        if response != KERN_SUCCESS:
             return None
         device = parent
     return device
@@ -172,7 +202,7 @@ def GetIOServicesByType(service_type):
 
     iokit.IOServiceGetMatchingServices(
             kIOMasterPortDefault,
-            iokit.IOServiceMatching(service_type.encode('mac_roman')),
+            iokit.IOServiceMatching(service_type.encode('utf-8')),
             ctypes.byref(serial_port_iterator))
 
     services = []
@@ -246,9 +276,12 @@ def comports(include_links=False):
                 # fetch some useful informations from properties
                 info.vid = get_int_property(usb_device, "idVendor", kCFNumberSInt16Type)
                 info.pid = get_int_property(usb_device, "idProduct", kCFNumberSInt16Type)
-                info.serial_number = get_string_property(usb_device, "USB Serial Number")
-                info.product = get_string_property(usb_device, "USB Product Name") or 'n/a'
-                info.manufacturer = get_string_property(usb_device, "USB Vendor Name")
+                info.serial_number = get_string_property(usb_device, kUSBSerialNumberString)
+                # We know this is a usb device, so the
+                # IORegistryEntryName should always be aliased to the
+                # usb product name string descriptor.
+                info.product = IORegistryEntryGetName(usb_device) or 'n/a'
+                info.manufacturer = get_string_property(usb_device, kUSBVendorString)
                 locationID = get_int_property(usb_device, "locationID", kCFNumberSInt32Type)
                 info.location = location_to_string(locationID)
                 info.interface = search_for_locationID_in_interfaces(serial_interfaces, locationID)