From ab3f8e3a272a4dc8bbe9ec479c20428b73d7bab4 Mon Sep 17 00:00:00 2001
From: Michael Forney <mforney@mforney.org>
Date: Thu, 7 Nov 2019 17:32:45 -0800
Subject: [PATCH] cmd/evm: Allow loading input from file

Some inputs might be too large to pass on the command-line.
---
 cmd/evm/main.go   |  5 +++++
 cmd/evm/runner.go | 14 ++++++++++++--
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/cmd/evm/main.go b/cmd/evm/main.go
index a5159c6b7ee4..5b8b950ab057 100644
--- a/cmd/evm/main.go
+++ b/cmd/evm/main.go
@@ -79,6 +79,10 @@ var (
 		Name:  "input",
 		Usage: "input for the EVM",
 	}
+	InputFileFlag = cli.StringFlag{
+		Name:  "inputfile",
+		Usage: "file containing input for the EVM",
+	}
 	VerbosityFlag = cli.IntFlag{
 		Name:  "verbosity",
 		Usage: "sets the verbosity level",
@@ -130,6 +134,7 @@ func init() {
 		ValueFlag,
 		DumpFlag,
 		InputFlag,
+		InputFileFlag,
 		MemProfileFlag,
 		CPUProfileFlag,
 		StatDumpFlag,
diff --git a/cmd/evm/runner.go b/cmd/evm/runner.go
index 3cbdcad01711..cecbf360639a 100644
--- a/cmd/evm/runner.go
+++ b/cmd/evm/runner.go
@@ -205,14 +205,24 @@ func runCmd(ctx *cli.Context) error {
 	}
 	tstart := time.Now()
 	var leftOverGas uint64
+	var hexInput []byte
+	if inputFileFlag := ctx.GlobalString(InputFileFlag.Name); inputFileFlag != "" {
+		if hexInput, err = ioutil.ReadFile(inputFileFlag); err != nil {
+			fmt.Printf("could not load input from file: %v\n", err)
+			os.Exit(1)
+		}
+	} else {
+		hexInput = []byte(ctx.GlobalString(InputFlag.Name))
+	}
+	input := common.FromHex(string(bytes.TrimSpace(hexInput)))
 	if ctx.GlobalBool(CreateFlag.Name) {
-		input := append(code, common.Hex2Bytes(ctx.GlobalString(InputFlag.Name))...)
+		input = append(code, input...)
 		ret, _, leftOverGas, err = runtime.Create(input, &runtimeConfig)
 	} else {
 		if len(code) > 0 {
 			statedb.SetCode(receiver, code)
 		}
-		ret, leftOverGas, err = runtime.Call(receiver, common.Hex2Bytes(ctx.GlobalString(InputFlag.Name)), &runtimeConfig)
+		ret, leftOverGas, err = runtime.Call(receiver, input, &runtimeConfig)
 	}
 	execTime := time.Since(tstart)