直接C指针转换

Question

我有这个 C 代码：

uint8_t *data[BUF_SIZE];

data = ...;

// extern void goReadData(uint8_t *data, int bufferSize);

goReadData(data, BUF_SIZE)

在 GO 代码中，我试图将data指针用作 GO 数组或切片，我想从 *C.uint8_t 中检索一个 []uint8。我知道尺寸data

//export goReadData

func goReadData(data *C.uint8_t, bufferSize C.int) {

    fmt.Printf("Data type %v\n", reflect.TypeOf(data))

    // print 1: Data type *main._Ctype_uchar

    // Solution 1: GoBytes

    // works but really slow (memory copy I think)

    goBytes := C.GoBytes(unsafe.Pointer(data), bufferSize)

    fmt.Printf("goBytes type %v\n", reflect.TypeOf(goBytes))

    // print 2: goBytes type []uint8

    // Solution 2: direct pointer

    // Really fast, but wrong type at the end

    // unsafe.Pointer to the C array

    unsafePtr := unsafe.Pointer(data)

    // convert unsafePtr to a pointer of the type *[1 << 30]C.uint8_t

    arrayPtr := (*[1 << 30]C.uint8_t)(unsafePtr)

    // slice the array into a Go slice, with the same backing array

    // as data, making sure to specify the capacity as well as

    // the length.

    length := int(bufferSize)

    slice := arrayPtr[0:length:length]

    fmt.Printf("Direct slice type %v\n", reflect.TypeOf(slice))

    //Print 3: Direct type []main._Ctype_uchar

}

我该怎么做才能[]uint8用第二种解决方案恢复 an 而不是 []main._Ctype_uchar？或者您是否有另一种解决方案可以在没有字节副本的情况下做到这一点？

Answer 1

抱歉，我发现了自己的错误：//&nbsp;convert&nbsp;unsafePtr&nbsp;to&nbsp;a&nbsp;pointer&nbsp;of&nbsp;the&nbsp;type&nbsp;*[1&nbsp;<<&nbsp;30]C.uint8_t arrayPtr&nbsp;:=&nbsp;(*[1&nbsp;<<&nbsp;30]C.uint8_t)(unsafePtr)==>到//&nbsp;convert&nbsp;unsafePtr&nbsp;to&nbsp;a&nbsp;pointer&nbsp;of&nbsp;the&nbsp;type&nbsp;*[1&nbsp;<<&nbsp;30]uint8 arrayPtr&nbsp;:=&nbsp;(*[1&nbsp;<<&nbsp;30]uint8)(unsafePtr)问题解决了！谢谢 ;）