scanwin32.py

   1 import ctypes
   2 import re
   3
   4 def ValidHandle(value):
   5     if value == 0:
   6         raise ctypes.WinError()
   7     return value
   8
   9 NULL = 0
  10 HDEVINFO = ctypes.c_int
  11 BOOL = ctypes.c_int
  12 CHAR = ctypes.c_char
  13 PCTSTR = ctypes.c_char_p
  14 HWND = ctypes.c_uint
  15 DWORD = ctypes.c_ulong
  16 PDWORD = ctypes.POINTER(DWORD)
  17 ULONG = ctypes.c_ulong
  18 ULONG_PTR = ctypes.POINTER(ULONG)
  19 #~ PBYTE = ctypes.c_char_p
  20 PBYTE = ctypes.c_void_p
  21
  22 class GUID(ctypes.Structure):
  23     _fields_ = [
  24         ('Data1', ctypes.c_ulong),
  25         ('Data2', ctypes.c_ushort),
  26         ('Data3', ctypes.c_ushort),
  27         ('Data4', ctypes.c_ubyte*8),
  28     ]
  29     def __str__(self):
  30         return "{%08x-%04x-%04x-%s-%s}" % (
  31             self.Data1,
  32             self.Data2,
  33             self.Data3,
  34             ''.join(["%02x" % d for d in self.Data4[:2]]),
  35             ''.join(["%02x" % d for d in self.Data4[2:]]),
  36         )
  37
  38 class SP_DEVINFO_DATA(ctypes.Structure):
  39     _fields_ = [
  40         ('cbSize', DWORD),
  41         ('ClassGuid', GUID),
  42         ('DevInst', DWORD),
  43         ('Reserved', ULONG_PTR),
  44     ]
  45     def __str__(self):
  46         return "ClassGuid:%s DevInst:%s" % (self.ClassGuid, self.DevInst)
  47 PSP_DEVINFO_DATA = ctypes.POINTER(SP_DEVINFO_DATA)
  48
  49 class SP_DEVICE_INTERFACE_DATA(ctypes.Structure):
  50     _fields_ = [
  51         ('cbSize', DWORD),
  52         ('InterfaceClassGuid', GUID),
  53         ('Flags', DWORD),
  54         ('Reserved', ULONG_PTR),
  55     ]
  56     def __str__(self):
  57         return "InterfaceClassGuid:%s Flags:%s" % (self.InterfaceClassGuid, self.Flags)
  58 PSP_DEVICE_INTERFACE_DATA = ctypes.POINTER(SP_DEVICE_INTERFACE_DATA)
  59
  60 PSP_DEVICE_INTERFACE_DETAIL_DATA = ctypes.c_void_p
  61
  62 SetupDiDestroyDeviceInfoList = ctypes.windll.setupapi.SetupDiDestroyDeviceInfoList
  63 SetupDiDestroyDeviceInfoList.argtypes = [HDEVINFO]
  64 SetupDiDestroyDeviceInfoList.restype = BOOL
  65
  66 SetupDiGetClassDevs = ctypes.windll.setupapi.SetupDiGetClassDevsA
  67 SetupDiGetClassDevs.argtypes = [ctypes.POINTER(GUID), PCTSTR, HWND, DWORD]
  68 SetupDiGetClassDevs.restype = ValidHandle #HDEVINFO
  69
  70 SetupDiEnumDeviceInterfaces = ctypes.windll.setupapi.SetupDiEnumDeviceInterfaces
  71 SetupDiEnumDeviceInterfaces.argtypes = [HDEVINFO, PSP_DEVINFO_DATA, ctypes.POINTER(GUID), DWORD, PSP_DEVICE_INTERFACE_DATA]
  72 SetupDiEnumDeviceInterfaces.restype = BOOL
  73
  74 SetupDiGetDeviceInterfaceDetail = ctypes.windll.setupapi.SetupDiGetDeviceInterfaceDetailA
  75 SetupDiGetDeviceInterfaceDetail.argtypes = [HDEVINFO, PSP_DEVICE_INTERFACE_DATA, PSP_DEVICE_INTERFACE_DETAIL_DATA, DWORD, PDWORD, PSP_DEVINFO_DATA]
  76 SetupDiGetDeviceInterfaceDetail.restype = BOOL
  77
  78 SetupDiGetDeviceRegistryProperty = ctypes.windll.setupapi.SetupDiGetDeviceRegistryPropertyA
  79 SetupDiGetDeviceRegistryProperty.argtypes = [HDEVINFO, PSP_DEVINFO_DATA, DWORD, PDWORD, PBYTE, DWORD, PDWORD]
  80 SetupDiGetDeviceRegistryProperty.restype = BOOL
  81
  82
  83 GUID_CLASS_COMPORT = GUID(0x86e0d1e0L, 0x8089, 0x11d0,
  84     (ctypes.c_ubyte*8)(0x9c, 0xe4, 0x08, 0x00, 0x3e, 0x30, 0x1f, 0x73))
  85
  86 DIGCF_PRESENT = 2
  87 DIGCF_DEVICEINTERFACE = 16
  88 INVALID_HANDLE_VALUE = 0
  89 ERROR_INSUFFICIENT_BUFFER = 122
  90 SPDRP_HARDWAREID = 1
  91 SPDRP_FRIENDLYNAME = 12
  92 ERROR_NO_MORE_ITEMS = 259
  93
  94 def comports(available_only=True):
  95     """This generator scans the device registry for com ports and yields port, desc, hwid.
  96        If available_only is true only return currently existing ports."""
  97     flags = DIGCF_DEVICEINTERFACE
  98     if available_only:
  99         flags |= DIGCF_PRESENT
 100     g_hdi = SetupDiGetClassDevs(ctypes.byref(GUID_CLASS_COMPORT), None, NULL, flags);
 101     #~ for i in range(256):
 102     for dwIndex in range(256):
 103         did = SP_DEVICE_INTERFACE_DATA()
 104         did.cbSize = ctypes.sizeof(did)
 105
 106         if not SetupDiEnumDeviceInterfaces(
 107             g_hdi,
 108             None,
 109             ctypes.byref(GUID_CLASS_COMPORT),
 110             dwIndex,
 111             ctypes.byref(did)
 112         ):
 113             if ctypes.GetLastError() != ERROR_NO_MORE_ITEMS:
 114                 raise ctypes.WinError()
 115             break
 116
 117         dwNeeded = DWORD()
 118         # get the size
 119         if not SetupDiGetDeviceInterfaceDetail(
 120             g_hdi,
 121             ctypes.byref(did),
 122             None, 0, ctypes.byref(dwNeeded),
 123             None
 124         ):
 125             # Ignore ERROR_INSUFFICIENT_BUFFER
 126             if ctypes.GetLastError() != ERROR_INSUFFICIENT_BUFFER:
 127                 raise ctypes.WinError()
 128         # allocate buffer
 129         class SP_DEVICE_INTERFACE_DETAIL_DATA_A(ctypes.Structure):
 130             _fields_ = [
 131                 ('cbSize', DWORD),
 132                 ('DevicePath', CHAR*(dwNeeded.value - ctypes.sizeof(DWORD))),
 133             ]
 134             def __str__(self):
 135                 return "DevicePath:%s" % (self.DevicePath,)
 136         idd = SP_DEVICE_INTERFACE_DETAIL_DATA_A()
 137         idd.cbSize = 5
 138         devinfo = SP_DEVINFO_DATA()
 139         devinfo.cbSize = ctypes.sizeof(devinfo)
 140         if not SetupDiGetDeviceInterfaceDetail(
 141             g_hdi,
 142             ctypes.byref(did),
 143             ctypes.byref(idd), dwNeeded, None,
 144             ctypes.byref(devinfo)
 145         ):
 146             raise ctypes.WinError()
 147
 148         # hardware ID
 149         szHardwareID = ctypes.create_string_buffer('\0' * 250)
 150         if not SetupDiGetDeviceRegistryProperty(
 151             g_hdi,
 152             ctypes.byref(devinfo),
 153             SPDRP_HARDWAREID,
 154             None,
 155             ctypes.byref(szHardwareID), ctypes.sizeof(szHardwareID) - 1,
 156             None
 157         ):
 158             # Ignore ERROR_INSUFFICIENT_BUFFER
 159             if ctypes.GetLastError() != ERROR_INSUFFICIENT_BUFFER:
 160                 raise ctypes.WinError()
 161
 162         # friendly name
 163         szFriendlyName = ctypes.create_string_buffer('\0' * 250)
 164         if not SetupDiGetDeviceRegistryProperty(
 165             g_hdi,
 166             ctypes.byref(devinfo),
 167             SPDRP_FRIENDLYNAME,
 168             None,
 169             ctypes.byref(szFriendlyName), ctypes.sizeof(szFriendlyName) - 1,
 170             None
 171         ):
 172             # Ignore ERROR_INSUFFICIENT_BUFFER
 173             if ctypes.GetLastError() != ERROR_INSUFFICIENT_BUFFER:
 174                 raise ctypes.WinError()
 175         port_name = re.search(r"\((.*)\)", szFriendlyName.value).group(1)
 176         if len(port_name) > 4:
 177             port_name = '\\\\.\\'+port_name
 178         yield port_name, szFriendlyName.value, szHardwareID.value
 179
 180     SetupDiDestroyDeviceInfoList(g_hdi)
 181
 182
 183 if __name__ == '__main__':
 184     import serial
 185     for port, desc, hwid in comports():
 186         print "%s: %s (%s)" % (port, desc, hwid)
 187         print " "*10, serial.Serial(port) #test open
 188
 189     # list of all ports the system knows
 190     print "-"*60
 191     for port, desc, hwid in comports(False):
 192         print "%-10s: %s (%s)" % (port, desc, hwid)