1 files changed, 100 insertions, 13 deletions
diff --git a/libgo/go/os/file.go b/libgo/go/os/file.go
index a2b71cb..416bc0e 100644
--- a/libgo/go/os/file.go
+++ b/libgo/go/os/file.go
@@ -45,6 +45,7 @@ import (
 	"internal/poll"
 	"internal/testlog"
 	"io"
+	"io/fs"
 	"runtime"
 	"syscall"
 	"time"
@@ -127,7 +128,7 @@ func (f *File) ReadAt(b []byte, off int64) (n int, err error) {
 	}
 
 	if off < 0 {
-		return 0, &PathError{"readat", f.name, errors.New("negative offset")}
+		return 0, &PathError{Op: "readat", Path: f.name, Err: errors.New("negative offset")}
 	}
 
 	for len(b) > 0 {
@@ -203,7 +204,7 @@ func (f *File) WriteAt(b []byte, off int64) (n int, err error) {
 	}
 
 	if off < 0 {
-		return 0, &PathError{"writeat", f.name, errors.New("negative offset")}
+		return 0, &PathError{Op: "writeat", Path: f.name, Err: errors.New("negative offset")}
 	}
 
 	for len(b) > 0 {
@@ -253,12 +254,15 @@ func (f *File) WriteString(s string) (n int, err error) {
 // If there is an error, it will be of type *PathError.
 func Mkdir(name string, perm FileMode) error {
 	if runtime.GOOS == "windows" && isWindowsNulName(name) {
-		return &PathError{"mkdir", name, syscall.ENOTDIR}
+		return &PathError{Op: "mkdir", Path: name, Err: syscall.ENOTDIR}
 	}
-	e := syscall.Mkdir(fixLongPath(name), syscallMode(perm))
+	longName := fixLongPath(name)
+	e := ignoringEINTR(func() error {
+		return syscall.Mkdir(longName, syscallMode(perm))
+	})
 
 	if e != nil {
-		return &PathError{"mkdir", name, e}
+		return &PathError{Op: "mkdir", Path: name, Err: e}
 	}
 
 	// mkdir(2) itself won't handle the sticky bit on *BSD and Solaris
@@ -288,7 +292,7 @@ func setStickyBit(name string) error {
 func Chdir(dir string) error {
 	if e := syscall.Chdir(dir); e != nil {
 		testlog.Open(dir) // observe likely non-existent directory
-		return &PathError{"chdir", dir, e}
+		return &PathError{Op: "chdir", Path: dir, Err: e}
 	}
 	if log := testlog.Logger(); log != nil {
 		wd, err := Getwd()
@@ -363,7 +367,7 @@ func (f *File) wrapErr(op string, err error) error {
 	if err == poll.ErrFileClosing {
 		err = ErrClosed
 	}
-	return &PathError{op, f.name, err}
+	return &PathError{Op: op, Path: f.name, Err: err}
 }
 
 // TempDir returns the default directory to use for temporary files.
@@ -402,7 +406,7 @@ func UserCacheDir() (string, error) {
 			return "", errors.New("%LocalAppData% is not defined")
 		}
 
-	case "darwin":
+	case "darwin", "ios":
 		dir = Getenv("HOME")
 		if dir == "" {
 			return "", errors.New("$HOME is not defined")
@@ -453,7 +457,7 @@ func UserConfigDir() (string, error) {
 			return "", errors.New("%AppData% is not defined")
 		}
 
-	case "darwin":
+	case "darwin", "ios":
 		dir = Getenv("HOME")
 		if dir == "" {
 			return "", errors.New("$HOME is not defined")
@@ -501,10 +505,8 @@ func UserHomeDir() (string, error) {
 	switch runtime.GOOS {
 	case "android":
 		return "/sdcard", nil
-	case "darwin":
-		if runtime.GOARCH == "arm64" {
-			return "/", nil
-		}
+	case "ios":
+		return "/", nil
 	}
 	return "", errors.New(enverr + " is not defined")
 }
@@ -605,3 +607,88 @@ func isWindowsNulName(name string) bool {
 	}
 	return true
 }
+
+// DirFS returns a file system (an fs.FS) for the tree of files rooted at the directory dir.
+//
+// Note that DirFS("/prefix") only guarantees that the Open calls it makes to the
+// operating system will begin with "/prefix": DirFS("/prefix").Open("file") is the
+// same as os.Open("/prefix/file"). So if /prefix/file is a symbolic link pointing outside
+// the /prefix tree, then using DirFS does not stop the access any more than using
+// os.Open does. DirFS is therefore not a general substitute for a chroot-style security
+// mechanism when the directory tree contains arbitrary content.
+func DirFS(dir string) fs.FS {
+	return dirFS(dir)
+}
+
+type dirFS string
+
+func (dir dirFS) Open(name string) (fs.File, error) {
+	if !fs.ValidPath(name) {
+		return nil, &PathError{Op: "open", Path: name, Err: ErrInvalid}
+	}
+	f, err := Open(string(dir) + "/" + name)
+	if err != nil {
+		return nil, err // nil fs.File
+	}
+	return f, nil
+}
+
+// ReadFile reads the named file and returns the contents.
+// A successful call returns err == nil, not err == EOF.
+// Because ReadFile reads the whole file, it does not treat an EOF from Read
+// as an error to be reported.
+func ReadFile(name string) ([]byte, error) {
+	f, err := Open(name)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	var size int
+	if info, err := f.Stat(); err == nil {
+		size64 := info.Size()
+		if int64(int(size64)) == size64 {
+			size = int(size64)
+		}
+	}
+	size++ // one byte for final read at EOF
+
+	// If a file claims a small size, read at least 512 bytes.
+	// In particular, files in Linux's /proc claim size 0 but
+	// then do not work right if read in small pieces,
+	// so an initial read of 1 byte would not work correctly.
+	if size < 512 {
+		size = 512
+	}
+
+	data := make([]byte, 0, size)
+	for {
+		if len(data) >= cap(data) {
+			d := append(data[:cap(data)], 0)
+			data = d[:len(data)]
+		}
+		n, err := f.Read(data[len(data):cap(data)])
+		data = data[:len(data)+n]
+		if err != nil {
+			if err == io.EOF {
+				err = nil
+			}
+			return data, err
+		}
+	}
+}
+
+// WriteFile writes data to the named file, creating it if necessary.
+// If the file does not exist, WriteFile creates it with permissions perm (before umask);
+// otherwise WriteFile truncates it before writing, without changing permissions.
+func WriteFile(name string, data []byte, perm FileMode) error {
+	f, err := OpenFile(name, O_WRONLY|O_CREATE|O_TRUNC, perm)
+	if err != nil {
+		return err
+	}
+	_, err = f.Write(data)
+	if err1 := f.Close(); err1 != nil && err == nil {
+		err = err1
+	}
+	return err
+}