Move response file handling to a separate package

sbox is going to need to read and write response files, move ReadRspFile
to its own package.

Test: response_test.go
Change-Id: Iecb5486b4aaeb2531828743ad8ef784df675e18e

cmd/merge_zips/Android.bp

@@ -22,7 +22,7 @@ blueprint_go_binary {
         "android-archive-zip",
         "blueprint-pathtools",
         "soong-jar",
-        "soong-zip",
+        "soong-response",
     ],
     srcs: [
         "merge_zips.go",

cmd/merge_zips/merge_zips.go

@@ -25,12 +25,14 @@ import (
 	"os"
 	"path/filepath"
 	"sort"
+	"strings"
+
+	"android/soong/response"
 
 	"github.com/google/blueprint/pathtools"
 
 	"android/soong/jar"
 	"android/soong/third_party/zip"
-	soongZip "android/soong/zip"
 )
 
 // Input zip: we can open it, close it, and obtain an array of entries
@@ -690,15 +692,20 @@ func main() {
 	inputs := make([]string, 0)
 	for _, input := range args[1:] {
 		if input[0] == '@' {
-			bytes, err := ioutil.ReadFile(input[1:])
+			f, err := os.Open(strings.TrimPrefix(input[1:], "@"))
 			if err != nil {
 				log.Fatal(err)
 			}
-			inputs = append(inputs, soongZip.ReadRespFile(bytes)...)
-			continue
+
+			rspInputs, err := response.ReadRspFile(f)
+			f.Close()
+			if err != nil {
+				log.Fatal(err)
+			}
+			inputs = append(inputs, rspInputs...)
+		} else {
+			inputs = append(inputs, input)
 		}
-		inputs = append(inputs, input)
-		continue
 	}
 
 	log.SetFlags(log.Lshortfile)

response/Android.bp

@@ -0,0 +1,16 @@
+package {
+    default_applicable_licenses: ["Android-Apache-2.0"],
+}
+
+bootstrap_go_package {
+    name: "soong-response",
+    pkgPath: "android/soong/response",
+    deps: [
+    ],
+    srcs: [
+        "response.go",
+    ],
+    testSrcs: [
+        "response_test.go",
+    ],
+}

response/response.go

@@ -0,0 +1,70 @@
+// Copyright 2021 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package response
+
+import (
+	"io"
+	"io/ioutil"
+	"unicode"
+)
+
+const noQuote = '\x00'
+
+// ReadRspFile reads a file in Ninja's response file format and returns its contents.
+func ReadRspFile(r io.Reader) ([]string, error) {
+	var files []string
+	var file []byte
+
+	buf, err := ioutil.ReadAll(r)
+	if err != nil {
+		return nil, err
+	}
+
+	isEscaping := false
+	quotingStart := byte(noQuote)
+	for _, c := range buf {
+		switch {
+		case isEscaping:
+			if quotingStart == '"' {
+				if !(c == '"' || c == '\\') {
+					// '\"' or '\\' will be escaped under double quoting.
+					file = append(file, '\\')
+				}
+			}
+			file = append(file, c)
+			isEscaping = false
+		case c == '\\' && quotingStart != '\'':
+			isEscaping = true
+		case quotingStart == noQuote && (c == '\'' || c == '"'):
+			quotingStart = c
+		case quotingStart != noQuote && c == quotingStart:
+			quotingStart = noQuote
+		case quotingStart == noQuote && unicode.IsSpace(rune(c)):
+			// Current character is a space outside quotes
+			if len(file) != 0 {
+				files = append(files, string(file))
+			}
+			file = file[:0]
+		default:
+			file = append(file, c)
+		}
+	}
+
+	if len(file) != 0 {
+		files = append(files, string(file))
+	}
+
+	return files, nil
+}

response/response_test.go

@@ -0,0 +1,96 @@
+// Copyright 2021 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package response
+
+import (
+	"bytes"
+	"reflect"
+	"testing"
+)
+
+func TestReadRspFile(t *testing.T) {
+	testCases := []struct {
+		name, in string
+		out      []string
+	}{
+		{
+			name: "single quoting test case 1",
+			in:   `./cmd '"'-C`,
+			out:  []string{"./cmd", `"-C`},
+		},
+		{
+			name: "single quoting test case 2",
+			in:   `./cmd '-C`,
+			out:  []string{"./cmd", `-C`},
+		},
+		{
+			name: "single quoting test case 3",
+			in:   `./cmd '\"'-C`,
+			out:  []string{"./cmd", `\"-C`},
+		},
+		{
+			name: "single quoting test case 4",
+			in:   `./cmd '\\'-C`,
+			out:  []string{"./cmd", `\\-C`},
+		},
+		{
+			name: "none quoting test case 1",
+			in:   `./cmd \'-C`,
+			out:  []string{"./cmd", `'-C`},
+		},
+		{
+			name: "none quoting test case 2",
+			in:   `./cmd \\-C`,
+			out:  []string{"./cmd", `\-C`},
+		},
+		{
+			name: "none quoting test case 3",
+			in:   `./cmd \"-C`,
+			out:  []string{"./cmd", `"-C`},
+		},
+		{
+			name: "double quoting test case 1",
+			in:   `./cmd "'"-C`,
+			out:  []string{"./cmd", `'-C`},
+		},
+		{
+			name: "double quoting test case 2",
+			in:   `./cmd "\\"-C`,
+			out:  []string{"./cmd", `\-C`},
+		},
+		{
+			name: "double quoting test case 3",
+			in:   `./cmd "\""-C`,
+			out:  []string{"./cmd", `"-C`},
+		},
+		{
+			name: "ninja rsp file",
+			in:   "'a'\nb\n'@'\n'foo'\\''bar'\n'foo\"bar'",
+			out:  []string{"a", "b", "@", "foo'bar", `foo"bar`},
+		},
+	}
+
+	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+			got, err := ReadRspFile(bytes.NewBuffer([]byte(testCase.in)))
+			if err != nil {
+				t.Errorf("unexpected error: %q", err)
+			}
+			if !reflect.DeepEqual(got, testCase.out) {
+				t.Errorf("expected %q got %q", testCase.out, got)
+			}
+		})
+	}
+}

zip/Android.bp

@@ -25,6 +25,7 @@ bootstrap_go_package {
         "android-archive-zip",
         "blueprint-pathtools",
         "soong-jar",
+        "soong-response",
     ],
     srcs: [
         "zip.go",

zip/cmd/main.go

@@ -24,7 +24,6 @@ package main
 import (
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"runtime"
 	"runtime/pprof"
@@ -32,6 +31,7 @@ import (
 	"strconv"
 	"strings"
 
+	"android/soong/response"
 	"android/soong/zip"
 )
 
@@ -125,12 +125,18 @@ func main() {
 	var expandedArgs []string
 	for _, arg := range os.Args {
 		if strings.HasPrefix(arg, "@") {
-			bytes, err := ioutil.ReadFile(strings.TrimPrefix(arg, "@"))
+			f, err := os.Open(strings.TrimPrefix(arg, "@"))
+			if err != nil {
+				fmt.Fprintln(os.Stderr, err.Error())
+				os.Exit(1)
+			}
+
+			respArgs, err := response.ReadRspFile(f)
+			f.Close()
 			if err != nil {
 				fmt.Fprintln(os.Stderr, err.Error())
 				os.Exit(1)
 			}
-			respArgs := zip.ReadRespFile(bytes)
 			expandedArgs = append(expandedArgs, respArgs...)
 		} else {
 			expandedArgs = append(expandedArgs, arg)

zip/zip.go

@@ -29,7 +29,8 @@ import (
 	"sync"
 	"syscall"
 	"time"
-	"unicode"
+
+	"android/soong/response"
 
 	"github.com/google/blueprint/pathtools"
 
@@ -164,14 +165,12 @@ func (b *FileArgsBuilder) RspFile(name string) *FileArgsBuilder {
 	}
 	defer f.Close()
 
-	list, err := ioutil.ReadAll(f)
+	arg := b.state
+	arg.SourceFiles, err = response.ReadRspFile(f)
 	if err != nil {
 		b.err = err
 		return b
 	}
-
-	arg := b.state
-	arg.SourceFiles = ReadRespFile(list)
 	for i := range arg.SourceFiles {
 		arg.SourceFiles[i] = pathtools.MatchEscape(arg.SourceFiles[i])
 	}
@@ -253,49 +252,6 @@ type ZipArgs struct {
 	Filesystem pathtools.FileSystem
 }
 
-const NOQUOTE = '\x00'
-
-func ReadRespFile(bytes []byte) []string {
-	var args []string
-	var arg []rune
-
-	isEscaping := false
-	quotingStart := NOQUOTE
-	for _, c := range string(bytes) {
-		switch {
-		case isEscaping:
-			if quotingStart == '"' {
-				if !(c == '"' || c == '\\') {
-					// '\"' or '\\' will be escaped under double quoting.
-					arg = append(arg, '\\')
-				}
-			}
-			arg = append(arg, c)
-			isEscaping = false
-		case c == '\\' && quotingStart != '\'':
-			isEscaping = true
-		case quotingStart == NOQUOTE && (c == '\'' || c == '"'):
-			quotingStart = c
-		case quotingStart != NOQUOTE && c == quotingStart:
-			quotingStart = NOQUOTE
-		case quotingStart == NOQUOTE && unicode.IsSpace(c):
-			// Current character is a space outside quotes
-			if len(arg) != 0 {
-				args = append(args, string(arg))
-			}
-			arg = arg[:0]
-		default:
-			arg = append(arg, c)
-		}
-	}
-
-	if len(arg) != 0 {
-		args = append(args, string(arg))
-	}
-
-	return args
-}
-
 func zipTo(args ZipArgs, w io.Writer) error {
 	if args.EmulateJar {
 		args.AddDirectoryEntriesToZip = true

zip/zip_test.go

@@ -535,78 +535,6 @@ func TestZip(t *testing.T) {
 	}
 }
 
-func TestReadRespFile(t *testing.T) {
-	testCases := []struct {
-		name, in string
-		out      []string
-	}{
-		{
-			name: "single quoting test case 1",
-			in:   `./cmd '"'-C`,
-			out:  []string{"./cmd", `"-C`},
-		},
-		{
-			name: "single quoting test case 2",
-			in:   `./cmd '-C`,
-			out:  []string{"./cmd", `-C`},
-		},
-		{
-			name: "single quoting test case 3",
-			in:   `./cmd '\"'-C`,
-			out:  []string{"./cmd", `\"-C`},
-		},
-		{
-			name: "single quoting test case 4",
-			in:   `./cmd '\\'-C`,
-			out:  []string{"./cmd", `\\-C`},
-		},
-		{
-			name: "none quoting test case 1",
-			in:   `./cmd \'-C`,
-			out:  []string{"./cmd", `'-C`},
-		},
-		{
-			name: "none quoting test case 2",
-			in:   `./cmd \\-C`,
-			out:  []string{"./cmd", `\-C`},
-		},
-		{
-			name: "none quoting test case 3",
-			in:   `./cmd \"-C`,
-			out:  []string{"./cmd", `"-C`},
-		},
-		{
-			name: "double quoting test case 1",
-			in:   `./cmd "'"-C`,
-			out:  []string{"./cmd", `'-C`},
-		},
-		{
-			name: "double quoting test case 2",
-			in:   `./cmd "\\"-C`,
-			out:  []string{"./cmd", `\-C`},
-		},
-		{
-			name: "double quoting test case 3",
-			in:   `./cmd "\""-C`,
-			out:  []string{"./cmd", `"-C`},
-		},
-		{
-			name: "ninja rsp file",
-			in:   "'a'\nb\n'@'\n'foo'\\''bar'\n'foo\"bar'",
-			out:  []string{"a", "b", "@", "foo'bar", `foo"bar`},
-		},
-	}
-
-	for _, testCase := range testCases {
-		t.Run(testCase.name, func(t *testing.T) {
-			got := ReadRespFile([]byte(testCase.in))
-			if !reflect.DeepEqual(got, testCase.out) {
-				t.Errorf("expected %q got %q", testCase.out, got)
-			}
-		})
-	}
-}
-
 func TestSrcJar(t *testing.T) {
 	mockFs := pathtools.MockFs(map[string][]byte{
 		"wrong_package.java":       []byte("package foo;"),