support ckb.loadTxHash

Author: douyixuan

pkg/ckb/native.cell

@@ -1,6 +1,8 @@
 package ckb
 
 extern (
+	func __slice_get_ptr(s []byte) uintptr
+
 	// reference from ckb_syscall_apis.h
 	func ckb_load_tx_hash(addr uintptr, len uint64, offset uint) int
 	func ckb_load_transaction(addr uintptr, len uint64, offset uint) int
@@ -20,3 +22,7 @@ extern (
 	// todo
 	// func ckb_exec_cell(code_hash *byte, hash_type uint8, offset uint32, length uint8, argc int, argv []*byte) int
 )
+
+const (
+	CKB_SUCCESS = 0
+)

pkg/ckb/syscalls.cell

@@ -0,0 +1,18 @@
+package ckb
+
+import (
+	// "blockchain"
+)
+
+const SIZE_H256 = 32
+
+func loadTxhash() []byte {
+	hash := make([]byte, SIZE_H256, SIZE_H256)
+	ptr := __slice_get_ptr(hash)
+	err := ckb_load_tx_hash(ptr, SIZE_H256, 0)
+	if err != CKB_SUCCESS {
+		return []byte{}
+	}
+	// var a blockchain.Byte32
+	return hash
+}