python如何调用CM_Get_Device_Interface_ListW

在Python中直接调用Windows API函数`CM_Get_Device_Interface_ListW`通常需要使用一些外部库，如`ctypes`库来桥接C语言与Python之间的数据类型和系统调用。这个API函数用于获取设备接口列表，通常是在处理硬件设备管理时会用到。

首先，你需要安装`ctypes`库，如果你还没有安装，可以使用pip进行安装：

pip install ctypes

然后，你可以按照以下步骤调用`CM_Get_Device_Interface_ListW`：

import ctypes
from ctypes.wintypes import *

# 定义必要的结构体和常量
windll.kernel32 = ctypes.windll.kernel32
GUID = ctypes.c_wchar_p
DEVICE_INTERFACE_DATA = ctypes.Structure([
    (ctypes.c_char * 16, GUID),
    (ctypes.c_ulong, DWORD),   # ClassGuid
    (ctypes.c_ulong, DWORD),   # ReferredInterface
    (ctypes.c_ulong, ULONG_PTR),  # InterfaceIndex
    (ctypes.c_char * 128, LPWSTR),  # DevicePath
])

class DEVICE_INFO_DATA(ctypes.Structure):
    _fields_ = [
        ('cbSize', DWORD),
        ('interfaceClassGuid', GUID),
        ('deviceInstanceID', LPWSTR)
    ]

CM_Get_Device_Interface_ListW = windll.kernel32.CM_Get_Device_Interface_ListW
CM_Get_Device_Interface_ListW.argtypes = [POINTER(DEVICE_INFO_DATA), POINTER(DWORD), DWORD, DWORD]

def get_device_interface_list():
    buffer_size = DWORD()
    devices = (DEVICE_INFO_DATA * 1)()
    result = CM_Get_Device_Interface_ListW(None, ctypes.byref(buffer_size), GIMME_ALL, GMCI_ENUMERATE)
    
    if result == ERROR_INSUFFICIENT_BUFFER:
        # 如果返回ERROR_INSUFFICIENT_BUFFER，说明缓冲区太小，需要动态分配更大的内存
        devices = (DEVICE_INFO_DATA * buffer_size.value)()
        result = CM_Get_Device_Interface_ListW(devices, ctypes.byref(buffer_size), GIMME_ALL, GMCI_ENUMERATE)

    if result != 0:
        print(f"Error calling CM_Get_Device_Interface_ListW: {result}")
        return

    print(f"Found {buffer_size.value} device interfaces:")
    for i in range(buffer_size.value):
        device = devices[i]
        print(f"- Class: {device.interfaceClassGuid.value}, Instance ID: {device.deviceInstanceID.decode()}")
        
get_device_interface_list()

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