Use interface for $(location) values in genrules

Use an interface instead of a string to retrieve the value for
$(location) or $(locations) expansions in genrules to allow
delaying the evaluation until the RuleBuilderCommand is available.
This allows using helpers like RuleBuilderCommand.PathForInputs
to properly rewrite the values for sandboxing.

Also remove the standalone SboxPathFor* methods that don't operate
on a specific RuleBuilderCommand that are now unnecessary.

Test: genrule_test.go
Change-Id: I8bb2647332ef118204a216cead23d062517e2b8c

android/rule_builder.go

@@ -793,13 +793,6 @@ func (c *RuleBuilderCommand) PathForOutput(path WritablePath) string {
 	return path.String()
 }
 
-// SboxPathForTool takes a path to a tool, which may be an output file or a source file, and returns
-// the corresponding path for the tool in the sbox sandbox.  It assumes that sandboxing and tool
-// sandboxing are enabled.
-func SboxPathForTool(ctx BuilderContext, path Path) string {
-	return filepath.Join(sboxSandboxBaseDir, sboxPathForToolRel(ctx, path))
-}
-
 func sboxPathForToolRel(ctx BuilderContext, path Path) string {
 	// Errors will be handled in RuleBuilder.Build where we have a context to report them
 	relOut, isRelOut, _ := maybeRelErr(PathForOutput(ctx, "host", ctx.Config().PrebuiltOS()).String(), path.String())
@@ -842,17 +835,21 @@ func (r *RuleBuilder) sboxPathsForInputsRel(paths Paths) []string {
 	return ret
 }
 
-// SboxPathForPackagedTool takes a PackageSpec for a tool and returns the corresponding path for the
-// tool after copying it into the sandbox.  This can be used  on the RuleBuilder command line to
-// reference the tool.
-func SboxPathForPackagedTool(spec PackagingSpec) string {
-	return filepath.Join(sboxSandboxBaseDir, sboxPathForPackagedToolRel(spec))
-}
-
 func sboxPathForPackagedToolRel(spec PackagingSpec) string {
 	return filepath.Join(sboxToolsSubDir, "out", spec.relPathInPackage)
 }
 
+// PathForPackagedTool takes a PackageSpec for a tool and returns the corresponding path for the
+// tool after copying it into the sandbox.  This can be used  on the RuleBuilder command line to
+// reference the tool.
+func (c *RuleBuilderCommand) PathForPackagedTool(spec PackagingSpec) string {
+	if !c.rule.sboxTools {
+		panic("PathForPackagedTool() requires SandboxTools()")
+	}
+
+	return filepath.Join(sboxSandboxBaseDir, sboxPathForPackagedToolRel(spec))
+}
+
 // PathForTool takes a path to a tool, which may be an output file or a source file, and returns
 // the corresponding path for the tool in the sbox sandbox if sbox is enabled, or the original path
 // if it is not.  This can be used  on the RuleBuilder command line to reference the tool.
@@ -863,6 +860,20 @@ func (c *RuleBuilderCommand) PathForTool(path Path) string {
 	return path.String()
 }
 
+// PathsForTools takes a list of paths to tools, which may be output files or source files, and
+// returns the corresponding paths for the tools in the sbox sandbox if sbox is enabled, or the
+// original paths if it is not.  This can be used  on the RuleBuilder command line to reference the tool.
+func (c *RuleBuilderCommand) PathsForTools(paths Paths) []string {
+	if c.rule.sbox && c.rule.sboxTools {
+		var ret []string
+		for _, path := range paths {
+			ret = append(ret, filepath.Join(sboxSandboxBaseDir, sboxPathForToolRel(c.rule.ctx, path)))
+		}
+		return ret
+	}
+	return paths.Strings()
+}
+
 // PackagedTool adds the specified tool path to the command line.  It can only be used with tool
 // sandboxing enabled by SandboxTools(), and will copy the tool into the sandbox.
 func (c *RuleBuilderCommand) PackagedTool(spec PackagingSpec) *RuleBuilderCommand {

genrule/Android.bp

@@ -16,6 +16,7 @@ bootstrap_go_package {
     ],
     srcs: [
         "genrule.go",
+        "locations.go",
     ],
     testSrcs: [
         "genrule_test.go",

genrule/genrule.go

@@ -91,7 +91,6 @@ var (
 
 func init() {
 	pctx.Import("android/soong/android")
-	pctx.HostBinToolVariable("sboxCmd", "sbox")
 
 	pctx.HostBinToolVariable("soongZip", "soong_zip")
 	pctx.HostBinToolVariable("zipSync", "zipsync")
@@ -254,18 +253,18 @@ func (g *Module) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 		g.exportedIncludeDirs = append(g.exportedIncludeDirs, android.PathForModuleGen(ctx, g.subDir))
 	}
 
-	locationLabels := map[string][]string{}
+	locationLabels := map[string]location{}
 	firstLabel := ""
 
-	addLocationLabel := func(label string, paths []string) {
+	addLocationLabel := func(label string, loc location) {
 		if firstLabel == "" {
 			firstLabel = label
 		}
 		if _, exists := locationLabels[label]; !exists {
-			locationLabels[label] = paths
+			locationLabels[label] = loc
 		} else {
 			ctx.ModuleErrorf("multiple labels for %q, %q and %q",
-				label, strings.Join(locationLabels[label], " "), strings.Join(paths, " "))
+				label, locationLabels[label], loc)
 		}
 	}
 
@@ -303,17 +302,17 @@ func (g *Module) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 						// sandbox.
 						packagedTools = append(packagedTools, specs...)
 						// Assume that the first PackagingSpec of the module is the tool.
-						addLocationLabel(tag.label, []string{android.SboxPathForPackagedTool(specs[0])})
+						addLocationLabel(tag.label, packagedToolLocation{specs[0]})
 					} else {
 						tools = append(tools, path.Path())
-						addLocationLabel(tag.label, []string{android.SboxPathForTool(ctx, path.Path())})
+						addLocationLabel(tag.label, toolLocation{android.Paths{path.Path()}})
 					}
 				case bootstrap.GoBinaryTool:
 					// A GoBinaryTool provides the install path to a tool, which will be copied.
 					if s, err := filepath.Rel(android.PathForOutput(ctx).String(), t.InstallPath()); err == nil {
 						toolPath := android.PathForOutput(ctx, s)
 						tools = append(tools, toolPath)
-						addLocationLabel(tag.label, []string{android.SboxPathForTool(ctx, toolPath)})
+						addLocationLabel(tag.label, toolLocation{android.Paths{toolPath}})
 					} else {
 						ctx.ModuleErrorf("cannot find path for %q: %v", tool, err)
 						return
@@ -335,7 +334,7 @@ func (g *Module) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 		if ctx.Config().AllowMissingDependencies() {
 			for _, tool := range g.properties.Tools {
 				if !seenTools[tool] {
-					addLocationLabel(tool, []string{"***missing tool " + tool + "***"})
+					addLocationLabel(tool, errorLocation{"***missing tool " + tool + "***"})
 				}
 			}
 		}
@@ -348,11 +347,7 @@ func (g *Module) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	for _, toolFile := range g.properties.Tool_files {
 		paths := android.PathsForModuleSrc(ctx, []string{toolFile})
 		tools = append(tools, paths...)
-		var sandboxPaths []string
+		addLocationLabel(toolFile, toolLocation{paths})
-		for _, path := range paths {
-			sandboxPaths = append(sandboxPaths, android.SboxPathForTool(ctx, path))
-		}
-		addLocationLabel(toolFile, sandboxPaths)
 	}
 
 	var srcFiles android.Paths
@@ -370,10 +365,10 @@ func (g *Module) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 			// The command that uses this placeholder file will never be executed because the rule will be
 			// replaced with an android.Error rule reporting the missing dependencies.
 			ctx.AddMissingDependencies(missingDeps)
-			addLocationLabel(in, []string{"***missing srcs " + in + "***"})
+			addLocationLabel(in, errorLocation{"***missing srcs " + in + "***"})
 		} else {
 			srcFiles = append(srcFiles, paths...)
-			addLocationLabel(in, paths.Strings())
+			addLocationLabel(in, inputLocation{paths})
 		}
 	}
 
@@ -408,7 +403,7 @@ func (g *Module) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 		cmd := rule.Command()
 
 		for _, out := range task.out {
-			addLocationLabel(out.Rel(), []string{cmd.PathForOutput(out)})
+			addLocationLabel(out.Rel(), outputLocation{out})
 		}
 
 		referencedDepfile := false
@@ -426,16 +421,17 @@ func (g *Module) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 				if len(g.properties.Tools) == 0 && len(g.properties.Tool_files) == 0 {
 					return reportError("at least one `tools` or `tool_files` is required if $(location) is used")
 				}
-				paths := locationLabels[firstLabel]
+				loc := locationLabels[firstLabel]
+				paths := loc.Paths(cmd)
 				if len(paths) == 0 {
 					return reportError("default label %q has no files", firstLabel)
 				} else if len(paths) > 1 {
 					return reportError("default label %q has multiple files, use $(locations %s) to reference it",
 						firstLabel, firstLabel)
 				}
-				return locationLabels[firstLabel][0], nil
+				return paths[0], nil
 			case "in":
-				return strings.Join(srcFiles.Strings(), " "), nil
+				return strings.Join(cmd.PathsForInputs(srcFiles), " "), nil
 			case "out":
 				var sandboxOuts []string
 				for _, out := range task.out {
@@ -453,7 +449,8 @@ func (g *Module) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 			default:
 				if strings.HasPrefix(name, "location ") {
 					label := strings.TrimSpace(strings.TrimPrefix(name, "location "))
-					if paths, ok := locationLabels[label]; ok {
+					if loc, ok := locationLabels[label]; ok {
+						paths := loc.Paths(cmd)
 						if len(paths) == 0 {
 							return reportError("label %q has no files", label)
 						} else if len(paths) > 1 {
@@ -466,7 +463,8 @@ func (g *Module) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 					}
 				} else if strings.HasPrefix(name, "locations ") {
 					label := strings.TrimSpace(strings.TrimPrefix(name, "locations "))
-					if paths, ok := locationLabels[label]; ok {
+					if loc, ok := locationLabels[label]; ok {
+						paths := loc.Paths(cmd)
 						if len(paths) == 0 {
 							return reportError("label %q has no files", label)
 						}
@@ -719,7 +717,7 @@ func NewGenSrcs() *Module {
 				outputDepfile = android.PathForModuleGen(ctx, genSubDir, "gensrcs.d")
 				depFixerTool := ctx.Config().HostToolPath(ctx, "dep_fixer")
 				fullCommand += fmt.Sprintf(" && %s -o $(depfile) %s",
-					android.SboxPathForTool(ctx, depFixerTool),
+					rule.Command().PathForTool(depFixerTool),
 					strings.Join(commandDepFiles, " "))
 				extraTools = append(extraTools, depFixerTool)
 			}

genrule/locations.go

@@ -0,0 +1,104 @@
+// 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 genrule
+
+import (
+	"strings"
+
+	"android/soong/android"
+)
+
+// location is used to service $(location) and $(locations) entries in genrule commands.
+type location interface {
+	Paths(cmd *android.RuleBuilderCommand) []string
+	String() string
+}
+
+// inputLocation is a $(location) result for an entry in the srcs property.
+type inputLocation struct {
+	paths android.Paths
+}
+
+func (l inputLocation) String() string {
+	return strings.Join(l.paths.Strings(), " ")
+}
+
+func (l inputLocation) Paths(cmd *android.RuleBuilderCommand) []string {
+	return cmd.PathsForInputs(l.paths)
+}
+
+var _ location = inputLocation{}
+
+// outputLocation is a $(location) result for an entry in the out property.
+type outputLocation struct {
+	path android.WritablePath
+}
+
+func (l outputLocation) String() string {
+	return l.path.String()
+}
+
+func (l outputLocation) Paths(cmd *android.RuleBuilderCommand) []string {
+	return []string{cmd.PathForOutput(l.path)}
+}
+
+var _ location = outputLocation{}
+
+// toolLocation is a $(location) result for an entry in the tools or tool_files property.
+type toolLocation struct {
+	paths android.Paths
+}
+
+func (l toolLocation) String() string {
+	return strings.Join(l.paths.Strings(), " ")
+}
+
+func (l toolLocation) Paths(cmd *android.RuleBuilderCommand) []string {
+	return cmd.PathsForTools(l.paths)
+}
+
+var _ location = toolLocation{}
+
+// packagedToolLocation is a $(location) result for an entry in the tools or tool_files property
+// that has PackagingSpecs.
+type packagedToolLocation struct {
+	spec android.PackagingSpec
+}
+
+func (l packagedToolLocation) String() string {
+	return l.spec.FileName()
+}
+
+func (l packagedToolLocation) Paths(cmd *android.RuleBuilderCommand) []string {
+	return []string{cmd.PathForPackagedTool(l.spec)}
+}
+
+var _ location = packagedToolLocation{}
+
+// errorLocation is a placeholder for a $(location) result that returns garbage to break the command
+// when error reporting is delayed by ALLOW_MISSING_DEPENDENCIES=true.
+type errorLocation struct {
+	err string
+}
+
+func (l errorLocation) String() string {
+	return l.err
+}
+
+func (l errorLocation) Paths(cmd *android.RuleBuilderCommand) []string {
+	return []string{l.err}
+}
+
+var _ location = errorLocation{}