// transact calls a method on an Objective-C object instance.
// It blocks until the call is complete.
//
// Code (>0) is the method id assigned by gobind.
// Code -1 is used to instruct Objective-C to decrement the ref count of
// the Objective-Co object.
func transact(ref *seq.Ref, descriptor string, code int, in *seq.Buffer) *seq.Buffer {
var (
res *C.uint8_t = nil
resLen C.size_t = 0
req *C.uint8_t = nil
reqLen C.size_t = 0
)
if len(in.Data) > 0 {
req = (*C.uint8_t)(unsafe.Pointer(&in.Data[0]))
reqLen = C.size_t(len(in.Data))
}
if debug {
fmt.Printf("transact: ref.Num = %d code = %d\n", ref.Num, code)
}
desc := cstrings.get(descriptor)
C.go_seq_recv(C.int32_t(ref.Num), desc, C.int(code), req, reqLen, &res, &resLen)
if resLen > 0 {
goSlice := (*[maxSliceLen]byte)(unsafe.Pointer(res))[:resLen]
out := new(seq.Buffer)
out.Data = make([]byte, int(resLen))
copy(out.Data, goSlice)
C.free(unsafe.Pointer(res))
// TODO: own or copy []bytes whose addresses were passed in.
return out
}
return nil
}
// Send is called by Java to send a request to run a Go function.
//export Send
func Send(descriptor string, code int, req *C.uint8_t, reqlen C.size_t, res **C.uint8_t, reslen *C.size_t) {
fn := seq.Registry[descriptor][code]
in := new(seq.Buffer)
if reqlen > 0 {
in.Data = (*[maxSliceLen]byte)(unsafe.Pointer(req))[:reqlen]
}
out := new(seq.Buffer)
fn(out, in)
seqToBuf(res, reslen, out)
}
// Send is called by Java to send a request to run a Go function.
//export Send
func Send(descriptor string, code int, req *C.uint8_t, reqlen C.size_t, res **C.uint8_t, reslen *C.size_t) {
fn := seq.Registry[descriptor][code]
if fn == nil {
panic(fmt.Sprintf("invalid descriptor(%s) and code(0x%x)", descriptor, code))
}
in := new(seq.Buffer)
if reqlen > 0 {
in.Data = (*[maxSliceLen]byte)(unsafe.Pointer(req))[:reqlen]
}
out := new(seq.Buffer)
fn(out, in)
// BUG(hyangah): the function returning a go byte slice (so fn writes a pointer into 'out') is unsafe.
// After fn is complete here, Go runtime is free to collect or move the pointed byte slice
// contents. (Explicitly calling runtime.GC here will surface the problem?)
// Without pinning support from Go side, it will be hard to fix it without extra copying.
seqToBuf(res, reslen, out)
}