我一直在研究GLFW绑定,我想通过glfw.SetUserPointer(...)将Queue结构传递给它,
这样,我就这样传递了它:
type CircularQueue struct {
Values []interface{}
Front, Rear int32
Capacity int32
}
func newCircularQueue(capacity int32) *CircularQueue {
if capacity < 1 {
log.Fatal("Capacity of Circular Queue Zero or Negative")
}
queue := &CircularQueue{Capacity: capacity}
queue.Values = make([]interface{}, capacity)
return queue
}
...
events := newCircularQueue(16)
window.SetUserPointer(unsafe.Pointer(events))
但是我遇到了运行时错误
panic: runtime error: cgo argument has Go pointer to Go pointer
我进行了一些挖掘,似乎...并且我引用:
Go code may pass a Go pointer to C provided the Go memory to which it
points does not contain any Go pointers. The C code must preserve this
property: it must not store any Go pointers in Go memory, even temporarily.
When passing a pointer to a field in a struct, the Go memory in question is
the memory occupied by the field, not the entire struct. When passing a
pointer to an element in an array or slice, the Go memory in question is the
entire array or the entire backing array of the slice.
但是,我的结构中没有指针,我很困惑:(
答案 0 :(得分:2)
解决方案非常简单。您必须弄平提供给C代码的内容。而不是传递循环队列,而是传递数据。
//C
int mysterious_c_func(const char* values, front int32_t, back int32_t, capacity int32_t);
// Go
type CircularQueue struct {
Values []char //this can't possibly work with interface.
Front, Rear int32
Capacity int32
}
...
var q CircularQueue
data := (*C.char)(unsafe.Pointer(q.values))
C.mysterious_c_func(data, C.int(queue.Front), C.int(queue.Rear), C.int(queue.Capacity))
但是真正的问题是您试图部分地在C中,部分在Go中实现复杂的数据结构。要么实现循环缓冲区