From 30402430427854b61e9836850d6163554c4c667d Mon Sep 17 00:00:00 2001
From: Martin Holst Swende <martin@swende.se>
Date: Tue, 15 Aug 2017 11:31:36 +0200
Subject: [PATCH] cmd/evm: add --receiver, support code from stdin (#14873)

---
 cmd/evm/main.go   |  7 +++++-
 cmd/evm/runner.go | 59 ++++++++++++++++++++++++++---------------------
 2 files changed, 39 insertions(+), 27 deletions(-)

diff --git a/cmd/evm/main.go b/cmd/evm/main.go
index 1892ae3d31..a2e3b048e7 100644
--- a/cmd/evm/main.go
+++ b/cmd/evm/main.go
@@ -53,7 +53,7 @@ var (
 	}
 	CodeFileFlag = cli.StringFlag{
 		Name:  "codefile",
-		Usage: "file containing EVM code",
+		Usage: "File containing EVM code. If '-' is specified, code is read from stdin ",
 	}
 	GasFlag = cli.Uint64Flag{
 		Name:  "gas",
@@ -102,6 +102,10 @@ var (
 		Name:  "sender",
 		Usage: "The transaction origin",
 	}
+	ReceiverFlag = cli.StringFlag{
+		Name:  "receiver",
+		Usage: "The transaction receiver (execution context)",
+	}
 	DisableMemoryFlag = cli.BoolFlag{
 		Name:  "nomemory",
 		Usage: "disable memory output",
@@ -131,6 +135,7 @@ func init() {
 		GenesisFlag,
 		MachineFlag,
 		SenderFlag,
+		ReceiverFlag,
 		DisableMemoryFlag,
 		DisableStackFlag,
 	}
diff --git a/cmd/evm/runner.go b/cmd/evm/runner.go
index 3f95a0c93a..ae56781103 100644
--- a/cmd/evm/runner.go
+++ b/cmd/evm/runner.go
@@ -84,6 +84,7 @@ func runCmd(ctx *cli.Context) error {
 		statedb     *state.StateDB
 		chainConfig *params.ChainConfig
 		sender      = common.StringToAddress("sender")
+		receiver    = common.StringToAddress("receiver")
 	)
 	if ctx.GlobalBool(MachineFlag.Name) {
 		tracer = NewJSONLogger(logconfig, os.Stdout)
@@ -104,46 +105,52 @@ func runCmd(ctx *cli.Context) error {
 	if ctx.GlobalString(SenderFlag.Name) != "" {
 		sender = common.HexToAddress(ctx.GlobalString(SenderFlag.Name))
 	}
-
 	statedb.CreateAccount(sender)
 
+	if ctx.GlobalString(ReceiverFlag.Name) != "" {
+		receiver = common.HexToAddress(ctx.GlobalString(ReceiverFlag.Name))
+	}
+
 	var (
 		code []byte
 		ret  []byte
 		err  error
 	)
-	if fn := ctx.Args().First(); len(fn) > 0 {
+	// The '--code' or '--codefile' flag overrides code in state
+	if ctx.GlobalString(CodeFileFlag.Name) != "" {
+		var hexcode []byte
+		var err error
+		// If - is specified, it means that code comes from stdin
+		if ctx.GlobalString(CodeFileFlag.Name) == "-" {
+			//Try reading from stdin
+			if hexcode, err = ioutil.ReadAll(os.Stdin); err != nil {
+				fmt.Printf("Could not load code from stdin: %v\n", err)
+				os.Exit(1)
+			}
+		} else {
+			// Codefile with hex assembly
+			if hexcode, err = ioutil.ReadFile(ctx.GlobalString(CodeFileFlag.Name)); err != nil {
+				fmt.Printf("Could not load code from file: %v\n", err)
+				os.Exit(1)
+			}
+		}
+		code = common.Hex2Bytes(string(bytes.TrimRight(hexcode, "\n")))
+
+	} else if ctx.GlobalString(CodeFlag.Name) != "" {
+		code = common.Hex2Bytes(ctx.GlobalString(CodeFlag.Name))
+	} else if fn := ctx.Args().First(); len(fn) > 0 {
+		// EASM-file to compile
 		src, err := ioutil.ReadFile(fn)
 		if err != nil {
 			return err
 		}
-
 		bin, err := compiler.Compile(fn, src, false)
 		if err != nil {
 			return err
 		}
 		code = common.Hex2Bytes(bin)
-	} else if ctx.GlobalString(CodeFlag.Name) != "" {
-		code = common.Hex2Bytes(ctx.GlobalString(CodeFlag.Name))
-	} else {
-		var hexcode []byte
-		if ctx.GlobalString(CodeFileFlag.Name) != "" {
-			var err error
-			hexcode, err = ioutil.ReadFile(ctx.GlobalString(CodeFileFlag.Name))
-			if err != nil {
-				fmt.Printf("Could not load code from file: %v\n", err)
-				os.Exit(1)
-			}
-		} else {
-			var err error
-			hexcode, err = ioutil.ReadAll(os.Stdin)
-			if err != nil {
-				fmt.Printf("Could not load code from stdin: %v\n", err)
-				os.Exit(1)
-			}
-		}
-		code = common.Hex2Bytes(string(bytes.TrimRight(hexcode, "\n")))
 	}
+
 	initialGas := ctx.GlobalUint64(GasFlag.Name)
 	runtimeConfig := runtime.Config{
 		Origin:   sender,
@@ -180,9 +187,9 @@ func runCmd(ctx *cli.Context) error {
 		input := append(code, common.Hex2Bytes(ctx.GlobalString(InputFlag.Name))...)
 		ret, _, leftOverGas, err = runtime.Create(input, &runtimeConfig)
 	} else {
-		receiver := common.StringToAddress("receiver")
-		statedb.SetCode(receiver, code)
-
+		if len(code) > 0 {
+			statedb.SetCode(receiver, code)
+		}
 		ret, leftOverGas, err = runtime.Call(receiver, common.Hex2Bytes(ctx.GlobalString(InputFlag.Name)), &runtimeConfig)
 	}
 	execTime := time.Since(tstart)