如何分配SP

如何分配SP_DEVICE_INTERFACE_DETAIL_DATA？(How to allocate SP_DEVICE_INTERFACE_DETAIL_DATA?)

SP_DEVICE_INTERFACE_DETAIL_DATA是一个可变长度结构，从包含其大小的字段开始，后跟一个数组（不是指向一个数组的指针）。

分配具有所需数组长度的结构的便捷方法是什么？

SP_DEVICE_INTERFACE_DETAIL_DATA is a variable-length structure, beginning with a field containing its size followed by an array (not a pointer to one).

What is a convenient way to allocate this structure with a desired array length?

最满意答案

我像MSalters建议的那样做了：

std::vector<char> rawbuf(sizeof (SP_DEVICE_INTERFACE_DETAIL_DATA) + bufferlen); SP_DEVICE_INTERFACE_DETAIL_DATA* pDIDD = reinterpret_cast<SP_DEVICE_INTERFACE_DETAIL_DATA*>(&rawbuf[0]);

编辑：

按照Raymond Chen的例子（也在他的博客上讨论过），我可以按如下方式分配SP_DEVICE_INTERFACE_DETAIL_DATA结构：

PSP_DEVICE_INTERFACE_DETAIL_DATA pDIDD = malloc(FIELD_OFFSET(SP_DEVICE_INTERFACE_DETAIL_DATA, DevicePath[bufferlen]));

I did it like MSalters suggested:

std::vector<char> rawbuf(sizeof (SP_DEVICE_INTERFACE_DETAIL_DATA) + bufferlen); SP_DEVICE_INTERFACE_DETAIL_DATA* pDIDD = reinterpret_cast<SP_DEVICE_INTERFACE_DETAIL_DATA*>(&rawbuf[0]);

Edit:

Following Raymond Chen's example (as also discussed on his blog) I could allocate the SP_DEVICE_INTERFACE_DETAIL_DATA structure as follows:

PSP_DEVICE_INTERFACE_DETAIL_DATA pDIDD = malloc(FIELD_OFFSET(SP_DEVICE_INTERFACE_DETAIL_DATA, DevicePath[bufferlen]));