From 8fb0c4b53d355681da4eed2e299bfe4a06929b0a Mon Sep 17 00:00:00 2001
From: Guillaume Ballet <gballet@gmail.com>
Date: Sun, 21 Oct 2018 15:44:32 +0200
Subject: [PATCH] cmd/ewasm: Tweak the way wasm files are executed

This can now be used to test code metering
by running the sentinel contract
---
 cmd/ewasm/main.go | 40 ++++++++++++++++++++++++++++++----------
 1 file changed, 30 insertions(+), 10 deletions(-)

diff --git a/cmd/ewasm/main.go b/cmd/ewasm/main.go
index 5440c57ff2..e67de3f526 100644
--- a/cmd/ewasm/main.go
+++ b/cmd/ewasm/main.go
@@ -25,6 +25,7 @@ import (
 	"os"
 	"strconv"
 
+	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/params"
 
 	"github.com/ethereum/go-ethereum/cmd/utils"
@@ -59,12 +60,30 @@ func runCmd(ctx *cli.Context) error {
 
 	if args.Present() {
 		filename := args.First()
-		input := args.Get(1)
+		inputStr := args.Get(1)
 		gas, err := strconv.ParseUint(args.Get(2), 10, 64)
 		if err != nil {
 			return fmt.Errorf("Error parsing gas number: %v", err)
 		}
 
+		// Convert the input
+		input := []byte{}
+		if inputStr[0:2] != "0x" {
+			return fmt.Errorf("Invalid input, it should be a hexadecimal number starting with 0x")
+		}
+		inputStr = inputStr[2:]
+		if len(inputStr)%2 == 1 {
+			inputStr = "0" + inputStr
+		}
+		for inputStr != "" {
+			x, err := strconv.ParseUint(inputStr[0:2], 16, 8)
+			if err != nil {
+				return fmt.Errorf("Invalid byte in input")
+			}
+			input = append(input, byte(x))
+			inputStr = inputStr[2:]
+		}
+
 		if fd, err := os.Open(filename); err == nil {
 
 			fi, _ := fd.Stat()
@@ -84,16 +103,17 @@ func runCmd(ctx *cli.Context) error {
 
 			contract := coreVM.NewContract(coreVM.AccountRef(callerAddr), coreVM.AccountRef(contractAddr), big.NewInt(100), gas)
 			contract.Code = code
+			contract.Input = input
+
+			permissiveContext := coreVM.Context{
+				CanTransfer: core.CanTransfer,
+				Transfer:    core.Transfer,
+			}
+
+			evm := coreVM.NewEVM(permissiveContext, statedb, &params.ChainConfig{}, coreVM.Config{})
+
+			evm.StateDB.SetCode(contractAddr, code)
 
-			evm := coreVM.NewEVM(coreVM.Context{}, statedb, &params.ChainConfig{}, coreVM.Config{})
-			// &ewasm.Contract{
-			// 	StateDB:  statedb,
-			// 	Gas:      100,
-			// 	Address:  &contractAddr,
-			// 	CodeAddr: &codeAddr,
-			// 	Module:   m,
-			// 	VM:       vm,
-			// }
 
 			output, leftOver, err := evm.Call(coreVM.AccountRef(callerAddr), contractAddr, input, gas, big.NewInt(0))