Allow primary builder to change working directory

Bug: 146437378
Test: pathtools/fs_test.go
Change-Id: I513ceb9b8b0b4f18223bc34ecad9846fe220709b

bootstrap/bootstrap.go

@@ -691,7 +691,7 @@ func (s *singleton) GenerateBuildActions(ctx blueprint.SingletonContext) {
 
 	if s.config.stage == StagePrimary {
 		mainNinjaFile := filepath.Join("$buildDir", "build.ninja")
-		primaryBuilderNinjaGlobFile := filepath.Join(BuildDir, bootstrapSubDir, "build-globs.ninja")
+		primaryBuilderNinjaGlobFile := absolutePath(filepath.Join(BuildDir, bootstrapSubDir, "build-globs.ninja"))
 
 		if _, err := os.Stat(primaryBuilderNinjaGlobFile); os.IsNotExist(err) {
 			err = ioutil.WriteFile(primaryBuilderNinjaGlobFile, nil, 0666)

bootstrap/cleanup.go

@@ -70,7 +70,7 @@ func removeAbandonedFilesUnder(ctx *blueprint.Context, config *Config,
 	for _, filePath := range filePaths {
 		isTarget := targets[filePath]
 		if !isTarget {
-			err = removeFileAndEmptyDirs(filePath)
+			err = removeFileAndEmptyDirs(absolutePath(filePath))
 			if err != nil {
 				return err
 			}

bootstrap/command.go

@@ -47,6 +47,8 @@ var (
 	BuildDir      string
 	NinjaBuildDir string
 	SrcDir        string
+
+	absSrcDir string
 )
 
 func init() {
@@ -76,8 +78,10 @@ func Main(ctx *blueprint.Context, config interface{}, extraNinjaFileDeps ...stri
 		debug.SetGCPercent(-1)
 	}
 
+	absSrcDir = ctx.SrcDir()
+
 	if cpuprofile != "" {
-		f, err := os.Create(cpuprofile)
+		f, err := os.Create(absolutePath(cpuprofile))
 		if err != nil {
 			fatalf("error opening cpuprofile: %s", err)
 		}
@@ -87,7 +91,7 @@ func Main(ctx *blueprint.Context, config interface{}, extraNinjaFileDeps ...stri
 	}
 
 	if traceFile != "" {
-		f, err := os.Create(traceFile)
+		f, err := os.Create(absolutePath(traceFile))
 		if err != nil {
 			fatalf("error opening trace: %s", err)
 		}
@@ -155,7 +159,7 @@ func Main(ctx *blueprint.Context, config interface{}, extraNinjaFileDeps ...stri
 	deps = append(deps, extraDeps...)
 
 	if docFile != "" {
-		err := writeDocs(ctx, docFile)
+		err := writeDocs(ctx, absolutePath(docFile))
 		if err != nil {
 			fatalErrors([]error{err})
 		}
@@ -180,7 +184,7 @@ func Main(ctx *blueprint.Context, config interface{}, extraNinjaFileDeps ...stri
 	var buf *bufio.Writer
 
 	if stage != StageMain || !emptyNinjaFile {
-		f, err = os.OpenFile(outFile, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, outFilePermissions)
+		f, err = os.OpenFile(absolutePath(outFile), os.O_WRONLY|os.O_CREATE|os.O_TRUNC, outFilePermissions)
 		if err != nil {
 			fatalf("error opening Ninja file: %s", err)
 		}
@@ -215,14 +219,14 @@ func Main(ctx *blueprint.Context, config interface{}, extraNinjaFileDeps ...stri
 			fatalErrors(errs)
 		}
 
-		err = ioutil.WriteFile(globFile, buffer, outFilePermissions)
+		err = ioutil.WriteFile(absolutePath(globFile), buffer, outFilePermissions)
 		if err != nil {
-			fatalf("error writing %s: %s", outFile, err)
+			fatalf("error writing %s: %s", globFile, err)
 		}
 	}
 
 	if depFile != "" {
-		err := deptools.WriteDepFile(depFile, outFile, deps)
+		err := deptools.WriteDepFile(absolutePath(depFile), outFile, deps)
 		if err != nil {
 			fatalf("error writing depfile: %s", err)
 		}
@@ -237,7 +241,7 @@ func Main(ctx *blueprint.Context, config interface{}, extraNinjaFileDeps ...stri
 	}
 
 	if memprofile != "" {
-		f, err := os.Create(memprofile)
+		f, err := os.Create(absolutePath(memprofile))
 		if err != nil {
 			fatalf("error opening memprofile: %s", err)
 		}
@@ -268,3 +272,10 @@ func fatalErrors(errs []error) {
 	}
 	os.Exit(1)
 }
+
+func absolutePath(path string) string {
+	if filepath.IsAbs(path) {
+		return path
+	}
+	return filepath.Join(absSrcDir, path)
+}

bootstrap/config.go

@@ -30,7 +30,7 @@ func bootstrapVariable(name string, value func() string) blueprint.Variable {
 }
 
 var (
-	// These variables are the only configuration needed by the boostrap
+	// These variables are the only configuration needed by the bootstrap
 	// modules.
 	srcDir = bootstrapVariable("srcDir", func() string {
 		return SrcDir

context.go

@@ -114,6 +114,7 @@ type Context struct {
 	globs    map[string]GlobPath
 	globLock sync.Mutex
 
+	srcDir         string
 	fs             pathtools.FileSystem
 	moduleListFile string
 }
@@ -448,6 +449,15 @@ func (c *Context) SetNameInterface(i NameInterface) {
 	c.nameInterface = i
 }
 
+func (c *Context) SetSrcDir(path string) {
+	c.srcDir = path
+	c.fs = pathtools.NewOsFs(path)
+}
+
+func (c *Context) SrcDir() string {
+	return c.srcDir
+}
+
 func singletonPkgPath(singleton Singleton) string {
 	typ := reflect.TypeOf(singleton)
 	for typ.Kind() == reflect.Ptr {

pathtools/fs.go

@@ -36,7 +36,7 @@ const (
 	DontFollowSymlinks = ShouldFollowSymlinks(false)
 )
 
-var OsFs FileSystem = osFs{}
+var OsFs FileSystem = &osFs{}
 
 func MockFs(files map[string][]byte) FileSystem {
 	fs := &mockFs{
@@ -123,11 +123,45 @@ type FileSystem interface {
 }
 
 // osFs implements FileSystem using the local disk.
-type osFs struct{}
+type osFs struct {
+	srcDir string
+}
 
-func (osFs) Open(name string) (ReaderAtSeekerCloser, error) { return os.Open(name) }
+func NewOsFs(path string) FileSystem {
-func (osFs) Exists(name string) (bool, bool, error) {
+	return &osFs{srcDir: path}
-	stat, err := os.Stat(name)
+}
+
+func (fs *osFs) removeSrcDirPrefix(path string) string {
+	if fs.srcDir == "" {
+		return path
+	}
+	rel, err := filepath.Rel(fs.srcDir, path)
+	if err != nil {
+		panic(fmt.Errorf("unexpected failure in removeSrcDirPrefix filepath.Rel(%s, %s): %s",
+			fs.srcDir, path, err))
+	}
+	if strings.HasPrefix(rel, "../") {
+		panic(fmt.Errorf("unexpected relative path outside directory in removeSrcDirPrefix filepath.Rel(%s, %s): %s",
+			fs.srcDir, path, rel))
+	}
+	return rel
+}
+
+func (fs *osFs) removeSrcDirPrefixes(paths []string) []string {
+	if fs.srcDir != "" {
+		for i, path := range paths {
+			paths[i] = fs.removeSrcDirPrefix(path)
+		}
+	}
+	return paths
+}
+
+func (fs *osFs) Open(name string) (ReaderAtSeekerCloser, error) {
+	return os.Open(filepath.Join(fs.srcDir, name))
+}
+
+func (fs *osFs) Exists(name string) (bool, bool, error) {
+	stat, err := os.Stat(filepath.Join(fs.srcDir, name))
 	if err == nil {
 		return true, stat.IsDir(), nil
 	} else if os.IsNotExist(err) {
@@ -137,45 +171,47 @@ func (osFs) Exists(name string) (bool, bool, error) {
 	}
 }
 
-func (osFs) IsDir(name string) (bool, error) {
+func (fs *osFs) IsDir(name string) (bool, error) {
-	info, err := os.Stat(name)
+	info, err := os.Stat(filepath.Join(fs.srcDir, name))
 	if err != nil {
 		return false, err
 	}
 	return info.IsDir(), nil
 }
 
-func (osFs) IsSymlink(name string) (bool, error) {
+func (fs *osFs) IsSymlink(name string) (bool, error) {
-	if info, err := os.Lstat(name); err != nil {
+	if info, err := os.Lstat(filepath.Join(fs.srcDir, name)); err != nil {
 		return false, err
 	} else {
 		return info.Mode()&os.ModeSymlink != 0, nil
 	}
 }
 
-func (fs osFs) Glob(pattern string, excludes []string, follow ShouldFollowSymlinks) (matches, dirs []string, err error) {
+func (fs *osFs) Glob(pattern string, excludes []string, follow ShouldFollowSymlinks) (matches, dirs []string, err error) {
 	return startGlob(fs, pattern, excludes, follow)
 }
 
-func (osFs) glob(pattern string) ([]string, error) {
+func (fs *osFs) glob(pattern string) ([]string, error) {
-	return filepath.Glob(pattern)
+	paths, err := filepath.Glob(filepath.Join(fs.srcDir, pattern))
+	fs.removeSrcDirPrefixes(paths)
+	return paths, err
 }
 
-func (osFs) Lstat(path string) (stats os.FileInfo, err error) {
+func (fs *osFs) Lstat(path string) (stats os.FileInfo, err error) {
-	return os.Lstat(path)
+	return os.Lstat(filepath.Join(fs.srcDir, path))
 }
 
-func (osFs) Stat(path string) (stats os.FileInfo, err error) {
+func (fs *osFs) Stat(path string) (stats os.FileInfo, err error) {
-	return os.Stat(path)
+	return os.Stat(filepath.Join(fs.srcDir, path))
 }
 
 // Returns a list of all directories under dir
-func (osFs) ListDirsRecursive(name string, follow ShouldFollowSymlinks) (dirs []string, err error) {
+func (fs *osFs) ListDirsRecursive(name string, follow ShouldFollowSymlinks) (dirs []string, err error) {
-	return listDirsRecursive(OsFs, name, follow)
+	return listDirsRecursive(fs, name, follow)
 }
 
-func (osFs) ReadDirNames(name string) ([]string, error) {
+func (fs *osFs) ReadDirNames(name string) ([]string, error) {
-	dir, err := os.Open(name)
+	dir, err := os.Open(filepath.Join(fs.srcDir, name))
 	if err != nil {
 		return nil, err
 	}
@@ -190,8 +226,8 @@ func (osFs) ReadDirNames(name string) ([]string, error) {
 	return contents, nil
 }
 
-func (osFs) Readlink(name string) (string, error) {
+func (fs *osFs) Readlink(name string) (string, error) {
-	return os.Readlink(name)
+	return os.Readlink(filepath.Join(fs.srcDir, name))
 }
 
 type mockFs struct {

pathtools/fs_test.go

@@ -22,6 +22,8 @@ import (
 	"testing"
 )
 
+const testdataDir = "testdata/dangling"
+
 func symlinkMockFs() *mockFs {
 	files := []string{
 		"a/a/a",
@@ -149,14 +151,8 @@ func TestFs_IsDir(t *testing.T) {
 	}
 
 	mock := symlinkMockFs()
-	fsList := []FileSystem{mock, OsFs}
-	names := []string{"mock", "os"}
 
-	os.Chdir("testdata/dangling")
+	run := func(t *testing.T, fs FileSystem) {
-	defer os.Chdir("../..")
-
-	for i, fs := range fsList {
-		t.Run(names[i], func(t *testing.T) {
 		for _, test := range testCases {
 			t.Run(test.name, func(t *testing.T) {
 				got, err := fs.IsDir(test.name)
@@ -166,8 +162,26 @@ func TestFs_IsDir(t *testing.T) {
 				}
 			})
 		}
-		})
 	}
+
+	t.Run("mock", func(t *testing.T) {
+		run(t, mock)
+	})
+
+	t.Run("os", func(t *testing.T) {
+		os.Chdir("testdata/dangling")
+		defer os.Chdir("../..")
+		run(t, OsFs)
+	})
+
+	t.Run("os relative srcDir", func(t *testing.T) {
+		run(t, NewOsFs(testdataDir))
+	})
+
+	t.Run("os absolute srcDir", func(t *testing.T) {
+		wd, _ := os.Getwd()
+		run(t, NewOsFs(filepath.Join(wd, testdataDir)))
+	})
 }
 
 func TestFs_ListDirsRecursiveFollowSymlinks(t *testing.T) {
@@ -200,15 +214,8 @@ func TestFs_ListDirsRecursiveFollowSymlinks(t *testing.T) {
 	}
 
 	mock := symlinkMockFs()
-	fsList := []FileSystem{mock, OsFs}
-	names := []string{"mock", "os"}
-
-	os.Chdir("testdata/dangling")
-	defer os.Chdir("../..")
-
-	for i, fs := range fsList {
-		t.Run(names[i], func(t *testing.T) {
 
+	run := func(t *testing.T, fs FileSystem) {
 		for _, test := range testCases {
 			t.Run(test.name, func(t *testing.T) {
 				got, err := fs.ListDirsRecursive(test.name, FollowSymlinks)
@@ -218,8 +225,26 @@ func TestFs_ListDirsRecursiveFollowSymlinks(t *testing.T) {
 				}
 			})
 		}
-		})
 	}
+
+	t.Run("mock", func(t *testing.T) {
+		run(t, mock)
+	})
+
+	t.Run("os", func(t *testing.T) {
+		os.Chdir("testdata/dangling")
+		defer os.Chdir("../..")
+		run(t, OsFs)
+	})
+
+	t.Run("os relative srcDir", func(t *testing.T) {
+		run(t, NewOsFs(testdataDir))
+	})
+
+	t.Run("os absolute srcDir", func(t *testing.T) {
+		wd, _ := os.Getwd()
+		run(t, NewOsFs(filepath.Join(wd, testdataDir)))
+	})
 }
 
 func TestFs_ListDirsRecursiveDontFollowSymlinks(t *testing.T) {
@@ -252,15 +277,8 @@ func TestFs_ListDirsRecursiveDontFollowSymlinks(t *testing.T) {
 	}
 
 	mock := symlinkMockFs()
-	fsList := []FileSystem{mock, OsFs}
-	names := []string{"mock", "os"}
-
-	os.Chdir("testdata/dangling")
-	defer os.Chdir("../..")
-
-	for i, fs := range fsList {
-		t.Run(names[i], func(t *testing.T) {
 
+	run := func(t *testing.T, fs FileSystem) {
 		for _, test := range testCases {
 			t.Run(test.name, func(t *testing.T) {
 				got, err := fs.ListDirsRecursive(test.name, DontFollowSymlinks)
@@ -270,8 +288,26 @@ func TestFs_ListDirsRecursiveDontFollowSymlinks(t *testing.T) {
 				}
 			})
 		}
-		})
 	}
+
+	t.Run("mock", func(t *testing.T) {
+		run(t, mock)
+	})
+
+	t.Run("os", func(t *testing.T) {
+		os.Chdir("testdata/dangling")
+		defer os.Chdir("../..")
+		run(t, OsFs)
+	})
+
+	t.Run("os relative srcDir", func(t *testing.T) {
+		run(t, NewOsFs(testdataDir))
+	})
+
+	t.Run("os absolute srcDir", func(t *testing.T) {
+		wd, _ := os.Getwd()
+		run(t, NewOsFs(filepath.Join(wd, testdataDir)))
+	})
 }
 
 func TestFs_Readlink(t *testing.T) {
@@ -321,15 +357,8 @@ func TestFs_Readlink(t *testing.T) {
 	}
 
 	mock := symlinkMockFs()
-	fsList := []FileSystem{mock, OsFs}
-	names := []string{"mock", "os"}
-
-	os.Chdir("testdata/dangling")
-	defer os.Chdir("../..")
-
-	for i, fs := range fsList {
-		t.Run(names[i], func(t *testing.T) {
 
+	run := func(t *testing.T, fs FileSystem) {
 		for _, test := range testCases {
 			t.Run(test.from, func(t *testing.T) {
 				got, err := fs.Readlink(test.from)
@@ -339,8 +368,26 @@ func TestFs_Readlink(t *testing.T) {
 				}
 			})
 		}
-		})
 	}
+
+	t.Run("mock", func(t *testing.T) {
+		run(t, mock)
+	})
+
+	t.Run("os", func(t *testing.T) {
+		os.Chdir("testdata/dangling")
+		defer os.Chdir("../..")
+		run(t, OsFs)
+	})
+
+	t.Run("os relative srcDir", func(t *testing.T) {
+		run(t, NewOsFs(testdataDir))
+	})
+
+	t.Run("os absolute srcDir", func(t *testing.T) {
+		wd, _ := os.Getwd()
+		run(t, NewOsFs(filepath.Join(wd, testdataDir)))
+	})
 }
 
 func TestFs_Lstat(t *testing.T) {
@@ -392,15 +439,8 @@ func TestFs_Lstat(t *testing.T) {
 	}
 
 	mock := symlinkMockFs()
-	fsList := []FileSystem{mock, OsFs}
-	names := []string{"mock", "os"}
-
-	os.Chdir("testdata/dangling")
-	defer os.Chdir("../..")
-
-	for i, fs := range fsList {
-		t.Run(names[i], func(t *testing.T) {
 
+	run := func(t *testing.T, fs FileSystem) {
 		for _, test := range testCases {
 			t.Run(test.name, func(t *testing.T) {
 				got, err := fs.Lstat(test.name)
@@ -417,8 +457,26 @@ func TestFs_Lstat(t *testing.T) {
 				}
 			})
 		}
-		})
 	}
+
+	t.Run("mock", func(t *testing.T) {
+		run(t, mock)
+	})
+
+	t.Run("os", func(t *testing.T) {
+		os.Chdir("testdata/dangling")
+		defer os.Chdir("../..")
+		run(t, OsFs)
+	})
+
+	t.Run("os relative srcDir", func(t *testing.T) {
+		run(t, NewOsFs(testdataDir))
+	})
+
+	t.Run("os absolute srcDir", func(t *testing.T) {
+		wd, _ := os.Getwd()
+		run(t, NewOsFs(filepath.Join(wd, testdataDir)))
+	})
 }
 
 func TestFs_Stat(t *testing.T) {
@@ -470,15 +528,8 @@ func TestFs_Stat(t *testing.T) {
 	}
 
 	mock := symlinkMockFs()
-	fsList := []FileSystem{mock, OsFs}
-	names := []string{"mock", "os"}
-
-	os.Chdir("testdata/dangling")
-	defer os.Chdir("../..")
-
-	for i, fs := range fsList {
-		t.Run(names[i], func(t *testing.T) {
 
+	run := func(t *testing.T, fs FileSystem) {
 		for _, test := range testCases {
 			t.Run(test.name, func(t *testing.T) {
 				got, err := fs.Stat(test.name)
@@ -495,8 +546,26 @@ func TestFs_Stat(t *testing.T) {
 				}
 			})
 		}
-		})
 	}
+
+	t.Run("mock", func(t *testing.T) {
+		run(t, mock)
+	})
+
+	t.Run("os", func(t *testing.T) {
+		os.Chdir("testdata/dangling")
+		defer os.Chdir("../..")
+		run(t, OsFs)
+	})
+
+	t.Run("os relative srcDir", func(t *testing.T) {
+		run(t, NewOsFs(testdataDir))
+	})
+
+	t.Run("os absolute srcDir", func(t *testing.T) {
+		wd, _ := os.Getwd()
+		run(t, NewOsFs(filepath.Join(wd, testdataDir)))
+	})
 }
 
 func TestMockFs_glob(t *testing.T) {
@@ -538,14 +607,8 @@ func TestMockFs_glob(t *testing.T) {
 	}
 
 	mock := symlinkMockFs()
-	fsList := []FileSystem{mock, OsFs}
-	names := []string{"mock", "os"}
 
-	os.Chdir("testdata/dangling")
+	run := func(t *testing.T, fs FileSystem) {
-	defer os.Chdir("../..")
-
-	for i, fs := range fsList {
-		t.Run(names[i], func(t *testing.T) {
 		for _, test := range testCases {
 			t.Run(test.pattern, func(t *testing.T) {
 				got, err := fs.glob(test.pattern)
@@ -557,8 +620,26 @@ func TestMockFs_glob(t *testing.T) {
 				}
 			})
 		}
-		})
 	}
+
+	t.Run("mock", func(t *testing.T) {
+		run(t, mock)
+	})
+
+	t.Run("os", func(t *testing.T) {
+		os.Chdir("testdata/dangling")
+		defer os.Chdir("../..")
+		run(t, OsFs)
+	})
+
+	t.Run("os relative srcDir", func(t *testing.T) {
+		run(t, NewOsFs(testdataDir))
+	})
+
+	t.Run("os absolute srcDir", func(t *testing.T) {
+		wd, _ := os.Getwd()
+		run(t, NewOsFs(filepath.Join(wd, testdataDir)))
+	})
 }
 
 func syscallError(err error) error {