Go: use cgo.Handle to pass channel pointers to Rust and back to Go

Fixes #3207

Passing uintptr(unsafe.Pointer) to rust and back to Go can break
the cgo pointer passing rules. Use cgo.Handle instead.

Signed-off-by: Rueian <[email protected]>

go/api/base_client.go

@@ -10,13 +10,14 @@ package api
 // #cgo darwin,arm64 LDFLAGS: -L${SRCDIR}/../rustbin/aarch64-apple-darwin
 // #include "../lib.h"
 //
-// void successCallback(void *channelPtr, struct CommandResponse *message);
-// void failureCallback(void *channelPtr, char *errMessage, RequestErrorType errType);
+// void successCallback(uintptr_t channelPtr, struct CommandResponse *message);
+// void failureCallback(uintptr_t channelPtr, char *errMessage, RequestErrorType errType);
 import "C"
 
 import (
 	"fmt"
 	"math"
+	"runtime/cgo"
 	"strconv"
 	"unsafe"
 
@@ -51,17 +52,17 @@ type payload struct {
 }
 
 //export successCallback
-func successCallback(channelPtr unsafe.Pointer, cResponse *C.struct_CommandResponse) {
+func successCallback(channelPtr C.uintptr_t, cResponse *C.struct_CommandResponse) {
 	response := cResponse
-	resultChannel := *(*chan payload)(channelPtr)
+	resultChannel := *(cgo.Handle(channelPtr).Value().(*chan payload))
 	resultChannel <- payload{value: response, error: nil}
 }
 
 //export failureCallback
-func failureCallback(channelPtr unsafe.Pointer, cErrorMessage *C.char, cErrorType C.RequestErrorType) {
+func failureCallback(channelPtr C.uintptr_t, cErrorMessage *C.char, cErrorType C.RequestErrorType) {
 	defer C.free_error_message(cErrorMessage)
 	msg := C.GoString(cErrorMessage)
-	resultChannel := *(*chan payload)(channelPtr)
+	resultChannel := *(cgo.Handle(channelPtr).Value().(*chan payload))
 	resultChannel <- payload{value: nil, error: errors.GoError(uint32(cErrorType), msg)}
 }
 
@@ -209,9 +210,6 @@ func (client *baseClient) executeCommandWithRoute(
 		argLengthsPtr = &argLengths[0]
 	}
 
-	resultChannel := make(chan payload)
-	resultChannelPtr := uintptr(unsafe.Pointer(&resultChannel))
-
 	var routeBytesPtr *C.uchar = nil
 	var routeBytesCount C.uintptr_t = 0
 	if route != nil {
@@ -228,6 +226,9 @@ func (client *baseClient) executeCommandWithRoute(
 		routeBytesPtr = (*C.uchar)(C.CBytes(msg))
 	}
 
+	resultChannel := make(chan payload)
+	resultChannelPtr := cgo.NewHandle(&resultChannel)
+
 	C.command(
 		client.coreClient,
 		C.uintptr_t(resultChannelPtr),
@@ -239,6 +240,7 @@ func (client *baseClient) executeCommandWithRoute(
 		routeBytesCount,
 	)
 	payload := <-resultChannel
+	resultChannelPtr.Delete()
 	if payload.error != nil {
 		return nil, payload.error
 	}