package vk

// #include <stdlib.h>

import "C"

import (

"runtime"

"unsafe"

"honnef.co/go/safeish"

)

type allocator struct {

allocs []unsafe.Pointer

pinner runtime.Pinner

}

func (a *allocator) free() {

for _, alloc := range a.allocs {

C.free(alloc)

}

a.allocs = nil

a.pinner.Unpin()

}

func pinAsCastedPtr[Dst ~*DstE, Src ~*SrcE, DstE, SrcE any](a *allocator, s Src) Dst {

ptr := safeish.Cast[Dst](s)

a.pinner.Pin(ptr)

return ptr

}

func pinSlice[Src ~[]SrcE, SrcE any](a *allocator, s Src) *SrcE {

if cap(s) == 0 {

return nil

}

ptr := unsafe.SliceData(s)

a.pinner.Pin(ptr)

return ptr

}

func pinSliceAsCastedPtr[Dst ~*DstE, Src ~[]SrcE, DstE, SrcE any](a *allocator, s Src) Dst {

ptr := safeish.SliceCastPtr[Dst](s)

a.pinner.Pin(ptr)

return ptr

}

func alloc[T any](a *allocator) *T {

return allocn[T](a, 1)

}

func allocn[T any](a *allocator, nmemb int) *T {

if nmemb == 0 {

return nil

}

m := (*T)(C.calloc(C.size_t(nmemb), C.size_t(unsafe.Sizeof(*new(T)))))

a.allocs = append(a.allocs, unsafe.Pointer(m))

return m

}