patch: os.File

README.md

@@ -213,8 +213,12 @@ Here are the Go packages that can be imported correctly:
 * [sync/atomic](https://pkg.go.dev/sync/atomic)
 * [sync](https://pkg.go.dev/sync) (partially)
 * [syscall](https://pkg.go.dev/syscall) (partially)
+* [errors](https://pkg.go.dev/errors) (partially)
+* [io](https://pkg.go.dev/io) (partially)
+* [io/fs](https://pkg.go.dev/io/fs) (partially)
 * [os](https://pkg.go.dev/os) (partially)
 * [reflect](https://pkg.go.dev/reflect) (partially)
+* [time](https://pkg.go.dev/time) (partially)
 
 
 ## Dependencies

internal/lib/fmt/print.go

@@ -7,9 +7,6 @@ package fmt
 import (
 	"io"
 	"os"
-	"reflect"
-	"strconv"
-	"sync"
 	"unicode/utf8"
 )
 
@@ -32,6 +29,7 @@ const (
 	invReflectString  = "<invalid reflect.Value>"
 )
 
+/* TODO(xsw):
 // State represents the printer state passed to custom formatters.
 // It provides access to the io.Writer interface plus information about
 // the flags and options for the operand's format specifier.
@@ -53,6 +51,7 @@ type State interface {
 type Formatter interface {
 	Format(f State, verb rune)
 }
+*/
 
 // Stringer is implemented by any value that has a String method,
 // which defines the “native” format for that value.
@@ -71,6 +70,7 @@ type GoStringer interface {
 	GoString() string
 }
 
+/* TODO(xsw):
 // FormatString returns a string representing the fully qualified formatting
 // directive captured by the State, followed by the argument verb. (State does not
 // itself contain the verb.) The result has a leading percent sign followed by any
@@ -95,6 +95,7 @@ func FormatString(state State, verb rune) string {
 	b = utf8.AppendRune(b, verb)
 	return string(b)
 }
+*/
 
 // Use simple []byte instead of bytes.Buffer to avoid large dependency.
 type buffer []byte
@@ -123,7 +124,8 @@ type pp struct {
 	arg any
 
 	// value is used instead of arg for reflect values.
-	value reflect.Value
+	// TODO(xsw):
+	// value reflect.Value
 
 	// fmt is used to format basic items such as integers or strings.
 	fmt fmt
@@ -142,13 +144,17 @@ type pp struct {
 	wrappedErrs []int
 }
 
+/* TODO(xsw):
 var ppFree = sync.Pool{
 	New: func() any { return new(pp) },
 }
+*/
 
 // newPrinter allocates a new pp struct or grabs a cached one.
 func newPrinter() *pp {
-	p := ppFree.Get().(*pp)
+	// TODO(xsw):
+	// p := ppFree.Get().(*pp)
+	p := &pp{}
 	p.panicking = false
 	p.erroring = false
 	p.wrapErrs = false
@@ -175,9 +181,11 @@ func (p *pp) free() {
 	}
 
 	p.arg = nil
-	p.value = reflect.Value{}
+	// TODO(xsw):
+	// p.value = reflect.Value{}
 	p.wrappedErrs = p.wrappedErrs[:0]
-	ppFree.Put(p)
+	// TODO(xsw):
+	// ppFree.Put(p)
 }
 
 func (p *pp) Width() (wid int, ok bool) { return p.fmt.wid, p.fmt.widPresent }
@@ -214,6 +222,7 @@ func (p *pp) WriteString(s string) (ret int, err error) {
 	return len(s), nil
 }
 
+/* TODO(xsw):
 // These routines end in 'f' and take a format string.
 
 // Fprintf formats according to a format specifier and writes to w.
@@ -250,6 +259,7 @@ func Appendf(b []byte, format string, a ...any) []byte {
 	p.free()
 	return b
 }
+*/
 
 // These routines do not take a format string
 
@@ -334,6 +344,7 @@ func Appendln(b []byte, a ...any) []byte {
 	return b
 }
 
+/* TODO(xsw):
 // getField gets the i'th field of the struct value.
 // If the field is itself is an interface, return a value for
 // the thing inside the interface, not the interface itself.
@@ -376,28 +387,33 @@ func (p *pp) unknownType(v reflect.Value) {
 	p.buf.writeString(v.Type().String())
 	p.buf.writeByte('?')
 }
+*/
 
 func (p *pp) badVerb(verb rune) {
-	p.erroring = true
+	/*
-	p.buf.writeString(percentBangString)
+		p.erroring = true
-	p.buf.writeRune(verb)
+		p.buf.writeString(percentBangString)
-	p.buf.writeByte('(')
+		p.buf.writeRune(verb)
-	switch {
+		p.buf.writeByte('(')
-	case p.arg != nil:
+		switch {
-		p.buf.writeString(reflect.TypeOf(p.arg).String())
+		case p.arg != nil:
-		p.buf.writeByte('=')
+			p.buf.writeString(reflect.TypeOf(p.arg).String())
-		p.printArg(p.arg, 'v')
+			p.buf.writeByte('=')
-	case p.value.IsValid():
+			p.printArg(p.arg, 'v')
-		p.buf.writeString(p.value.Type().String())
+		case p.value.IsValid():
-		p.buf.writeByte('=')
+			p.buf.writeString(p.value.Type().String())
-		p.printValue(p.value, 'v', 0)
+			p.buf.writeByte('=')
-	default:
+			p.printValue(p.value, 'v', 0)
-		p.buf.writeString(nilAngleString)
+		default:
-	}
+			p.buf.writeString(nilAngleString)
-	p.buf.writeByte(')')
+		}
-	p.erroring = false
+		p.buf.writeByte(')')
+		p.erroring = false
+	*/
+	panic("todo: fmt.(*pp).badVerb")
 }
 
+/* TODO(xsw):
 func (p *pp) fmtBool(v bool, verb rune) {
 	switch verb {
 	case 't', 'v':
@@ -483,6 +499,7 @@ func (p *pp) fmtComplex(v complex128, size int, verb rune) {
 		p.badVerb(verb)
 	}
 }
+*/
 
 func (p *pp) fmtString(v string, verb rune) {
 	switch verb {
@@ -505,6 +522,7 @@ func (p *pp) fmtString(v string, verb rune) {
 	}
 }
 
+/* TODO(xsw):
 func (p *pp) fmtBytes(v []byte, verb rune, typeString string) {
 	switch verb {
 	case 'v', 'd':
@@ -541,10 +559,12 @@ func (p *pp) fmtBytes(v []byte, verb rune, typeString string) {
 	case 'q':
 		p.fmt.fmtQ(string(v))
 	default:
-		p.printValue(reflect.ValueOf(v), verb, 0)
+		// p.printValue(reflect.ValueOf(v), verb, 0)
+		panic("todo: fmt.(*pp).fmtBytes")
 	}
 }
 
+/* TODO(xsw):
 func (p *pp) fmtPointer(value reflect.Value, verb rune) {
 	var u uintptr
 	switch value.Kind() {
@@ -676,10 +696,12 @@ func (p *pp) handleMethods(verb rune) (handled bool) {
 	}
 	return false
 }
+*/
 
 func (p *pp) printArg(arg any, verb rune) {
 	p.arg = arg
-	p.value = reflect.Value{}
+	// TODO(xsw):
+	// p.value = reflect.Value{}
 
 	if arg == nil {
 		switch verb {
@@ -695,49 +717,54 @@ func (p *pp) printArg(arg any, verb rune) {
 	// %T (the value's type) and %p (its address) are special; we always do them first.
 	switch verb {
 	case 'T':
-		p.fmt.fmtS(reflect.TypeOf(arg).String())
+		// p.fmt.fmtS(reflect.TypeOf(arg).String())
-		return
+		// return
+		panic("todo: fmt.(*pp).printArg")
 	case 'p':
-		p.fmtPointer(reflect.ValueOf(arg), 'p')
+		// p.fmtPointer(reflect.ValueOf(arg), 'p')
-		return
+		// return
+		panic("todo: fmt.(*pp).printArg")
 	}
 
 	// Some types can be done without reflection.
 	switch f := arg.(type) {
-	case bool:
+	/*
-		p.fmtBool(f, verb)
+		case bool:
-	case float32:
+			p.fmtBool(f, verb)
-		p.fmtFloat(float64(f), 32, verb)
+		case float32:
-	case float64:
+			p.fmtFloat(float64(f), 32, verb)
-		p.fmtFloat(f, 64, verb)
+		case float64:
-	case complex64:
+			p.fmtFloat(f, 64, verb)
-		p.fmtComplex(complex128(f), 64, verb)
+		case complex64:
-	case complex128:
+			p.fmtComplex(complex128(f), 64, verb)
-		p.fmtComplex(f, 128, verb)
+		case complex128:
-	case int:
+			p.fmtComplex(f, 128, verb)
-		p.fmtInteger(uint64(f), signed, verb)
+		case int:
-	case int8:
+			p.fmtInteger(uint64(f), signed, verb)
-		p.fmtInteger(uint64(f), signed, verb)
+		case int8:
-	case int16:
+			p.fmtInteger(uint64(f), signed, verb)
-		p.fmtInteger(uint64(f), signed, verb)
+		case int16:
-	case int32:
+			p.fmtInteger(uint64(f), signed, verb)
-		p.fmtInteger(uint64(f), signed, verb)
+		case int32:
-	case int64:
+			p.fmtInteger(uint64(f), signed, verb)
-		p.fmtInteger(uint64(f), signed, verb)
+		case int64:
-	case uint:
+			p.fmtInteger(uint64(f), signed, verb)
-		p.fmtInteger(uint64(f), unsigned, verb)
+		case uint:
-	case uint8:
+			p.fmtInteger(uint64(f), unsigned, verb)
-		p.fmtInteger(uint64(f), unsigned, verb)
+		case uint8:
-	case uint16:
+			p.fmtInteger(uint64(f), unsigned, verb)
-		p.fmtInteger(uint64(f), unsigned, verb)
+		case uint16:
-	case uint32:
+			p.fmtInteger(uint64(f), unsigned, verb)
-		p.fmtInteger(uint64(f), unsigned, verb)
+		case uint32:
-	case uint64:
+			p.fmtInteger(uint64(f), unsigned, verb)
-		p.fmtInteger(f, unsigned, verb)
+		case uint64:
-	case uintptr:
+			p.fmtInteger(f, unsigned, verb)
-		p.fmtInteger(uint64(f), unsigned, verb)
+		case uintptr:
+			p.fmtInteger(uint64(f), unsigned, verb)
+	*/
 	case string:
 		p.fmtString(f, verb)
+	/* TODO(xsw):
 	case []byte:
 		p.fmtBytes(f, verb, "[]byte")
 	case reflect.Value:
@@ -750,16 +777,21 @@ func (p *pp) printArg(arg any, verb rune) {
 			}
 		}
 		p.printValue(f, verb, 0)
+	*/
 	default:
-		// If the type is not simple, it might have methods.
+		/*
-		if !p.handleMethods(verb) {
+			// If the type is not simple, it might have methods.
-			// Need to use reflection, since the type had no
+			if !p.handleMethods(verb) {
-			// interface methods that could be used for formatting.
+				// Need to use reflection, since the type had no
-			p.printValue(reflect.ValueOf(f), verb, 0)
+				// interface methods that could be used for formatting.
-		}
+				p.printValue(reflect.ValueOf(f), verb, 0)
+			}
+		*/
+		panic("todo: fmt.(*pp).printArg")
 	}
 }
 
+/*
 // printValue is similar to printArg but starts with a reflect value, not an interface{} value.
 // It does not handle 'p' and 'T' verbs because these should have been already handled by printArg.
 func (p *pp) printValue(value reflect.Value, verb rune, depth int) {
@@ -802,37 +834,34 @@ func (p *pp) printValue(value reflect.Value, verb rune, depth int) {
 	case reflect.String:
 		p.fmtString(f.String(), verb)
 	case reflect.Map:
-		/*
+		if p.fmt.sharpV {
-			if p.fmt.sharpV {
+			p.buf.writeString(f.Type().String())
-				p.buf.writeString(f.Type().String())
+			if f.IsNil() {
-				if f.IsNil() {
+				p.buf.writeString(nilParenString)
-					p.buf.writeString(nilParenString)
+				return
-					return
+			}
+			p.buf.writeByte('{')
+		} else {
+			p.buf.writeString(mapString)
+		}
+		sorted := fmtsort.Sort(f)
+		for i, key := range sorted.Key {
+			if i > 0 {
+				if p.fmt.sharpV {
+					p.buf.writeString(commaSpaceString)
+				} else {
+					p.buf.writeByte(' ')
 				}
-				p.buf.writeByte('{')
-			} else {
-				p.buf.writeString(mapString)
 			}
-			sorted := fmtsort.Sort(f)
+			p.printValue(key, verb, depth+1)
-			for i, key := range sorted.Key {
+			p.buf.writeByte(':')
-				if i > 0 {
+			p.printValue(sorted.Value[i], verb, depth+1)
-					if p.fmt.sharpV {
+		}
-						p.buf.writeString(commaSpaceString)
+		if p.fmt.sharpV {
-					} else {
+			p.buf.writeByte('}')
-						p.buf.writeByte(' ')
+		} else {
-					}
+			p.buf.writeByte(']')
-				}
+		}
-				p.printValue(key, verb, depth+1)
-				p.buf.writeByte(':')
-				p.printValue(sorted.Value[i], verb, depth+1)
-			}
-			if p.fmt.sharpV {
-				p.buf.writeByte('}')
-			} else {
-				p.buf.writeByte(']')
-			}
-		*/
-		panic("todo")
 	case reflect.Struct:
 		if p.fmt.sharpV {
 			p.buf.writeString(f.Type().String())
@@ -934,6 +963,7 @@ func (p *pp) printValue(value reflect.Value, verb rune, depth int) {
 	}
 }
 
+/* TODO(xsw):
 // intFromArg gets the argNumth element of a. On return, isInt reports whether the argument has integer type.
 func intFromArg(a []any, argNum int) (num int, isInt bool, newArgNum int) {
 	newArgNum = argNum
@@ -1201,18 +1231,22 @@ formatLoop:
 		p.buf.writeByte(')')
 	}
 }
+*/
 
 func (p *pp) doPrint(a []any) {
-	prevString := false
+	/*
-	for argNum, arg := range a {
+		prevString := false
-		isString := arg != nil && reflect.TypeOf(arg).Kind() == reflect.String
+		for argNum, arg := range a {
-		// Add a space between two non-string arguments.
+			isString := arg != nil && reflect.TypeOf(arg).Kind() == reflect.String
-		if argNum > 0 && !isString && !prevString {
+			// Add a space between two non-string arguments.
-			p.buf.writeByte(' ')
+			if argNum > 0 && !isString && !prevString {
+				p.buf.writeByte(' ')
+			}
+			p.printArg(arg, 'v')
+			prevString = isString
 		}
-		p.printArg(arg, 'v')
+	*/
-		prevString = isString
+	panic("todo: fmt.(*pp).doPrint")
-	}
 }
 
 // doPrintln is like doPrint but always adds a space between arguments

internal/lib/os/file.go

@@ -8,6 +8,7 @@ import (
 	"errors"
 	"io"
 	"syscall"
+	"time"
 )
 
 // Name returns the name of the file as presented to Open.
@@ -172,36 +173,42 @@ func (f *File) WriteAt(b []byte, off int64) (n int, err error) {
 		}
 		return
 	*/
-	panic("todo")
+	panic("todo: os.(*File).WriteAt")
 }
 
-/*
 // Seek sets the offset for the next Read or Write on file to offset, interpreted
 // according to whence: 0 means relative to the origin of the file, 1 means
 // relative to the current offset, and 2 means relative to the end.
 // It returns the new offset and an error, if any.
 // The behavior of Seek on a file opened with O_APPEND is not specified.
 func (f *File) Seek(offset int64, whence int) (ret int64, err error) {
-	if err := f.checkValid("seek"); err != nil {
+	/*
-		return 0, err
+		if err := f.checkValid("seek"); err != nil {
-	}
+			return 0, err
-	r, e := f.seek(offset, whence)
+		}
-	if e == nil && f.dirinfo != nil && r != 0 {
+		r, e := f.seek(offset, whence)
-		e = syscall.EISDIR
+		if e == nil && f.dirinfo != nil && r != 0 {
-	}
+			e = syscall.EISDIR
-	if e != nil {
+		}
-		return 0, f.wrapErr("seek", e)
+		if e != nil {
-	}
+			return 0, f.wrapErr("seek", e)
-	return r, nil
+		}
+		return r, nil
+	*/
+	panic("todo: os.(*File).Seek")
 }
 
 // WriteString is like Write, but writes the contents of string s rather than
 // a slice of bytes.
 func (f *File) WriteString(s string) (n int, err error) {
-	b := unsafe.Slice(unsafe.StringData(s), len(s))
+	/*
-	return f.Write(b)
+		b := unsafe.Slice(unsafe.StringData(s), len(s))
+		return f.Write(b)
+	*/
+	panic("todo: os.(*File).WriteString")
 }
 
+/*
 // setStickyBit adds ModeSticky to the permission bits of path, non atomic.
 func setStickyBit(name string) error {
 	fi, err := Stat(name)
@@ -293,6 +300,7 @@ func (f *File) wrapErr(op string, err error) error {
 func TempDir() string {
 	return tempDir()
 }
+*/
 
 // Chmod changes the mode of the file to mode.
 // If there is an error, it will be of type *PathError.
@@ -347,12 +355,16 @@ func (f *File) SetWriteDeadline(t time.Time) error {
 // SyscallConn returns a raw file.
 // This implements the syscall.Conn interface.
 func (f *File) SyscallConn() (syscall.RawConn, error) {
-	if err := f.checkValid("SyscallConn"); err != nil {
+	/*
-		return nil, err
+		if err := f.checkValid("SyscallConn"); err != nil {
-	}
+			return nil, err
-	return newRawConn(f)
+		}
+		return newRawConn(f)
+	*/
+	panic("todo: os.(*File).SyscallConn")
 }
 
+/* TODO(xsw):
 // 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

internal/lib/os/file_posix.go

@@ -0,0 +1,243 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm) || wasip1 || windows
+
+package os
+
+import (
+	"syscall"
+	"time"
+)
+
+// Close closes the File, rendering it unusable for I/O.
+// On files that support SetDeadline, any pending I/O operations will
+// be canceled and return immediately with an ErrClosed error.
+// Close will return an error if it has already been called.
+func (f *File) Close() error {
+	/*
+		if f == nil {
+			return ErrInvalid
+		}
+		return f.file.close()
+	*/
+	panic("todo: os.(*File).Close")
+}
+
+// pread reads len(b) bytes from the File starting at byte offset off.
+// It returns the number of bytes read and the error, if any.
+// EOF is signaled by a zero count with err set to nil.
+func (f *File) pread(b []byte, off int64) (n int, err error) {
+	/*
+		n, err = f.pfd.Pread(b, off)
+		runtime.KeepAlive(f)
+		return n, err
+	*/
+	panic("todo: os.(*File).pread")
+}
+
+// pwrite writes len(b) bytes to the File starting at byte offset off.
+// It returns the number of bytes written and an error, if any.
+func (f *File) pwrite(b []byte, off int64) (n int, err error) {
+	/*
+		n, err = f.pfd.Pwrite(b, off)
+		runtime.KeepAlive(f)
+		return n, err
+	*/
+	panic("todo: os.(*File).pwrite")
+}
+
+/*
+// syscallMode returns the syscall-specific mode bits from Go's portable mode bits.
+func syscallMode(i FileMode) (o uint32) {
+	o |= uint32(i.Perm())
+	if i&ModeSetuid != 0 {
+		o |= syscall.S_ISUID
+	}
+	if i&ModeSetgid != 0 {
+		o |= syscall.S_ISGID
+	}
+	if i&ModeSticky != 0 {
+		o |= syscall.S_ISVTX
+	}
+	// No mapping for Go's ModeTemporary (plan9 only).
+	return
+}
+
+// See docs in file.go:Chmod.
+func chmod(name string, mode FileMode) error {
+	longName := fixLongPath(name)
+	e := ignoringEINTR(func() error {
+		return syscall.Chmod(longName, syscallMode(mode))
+	})
+	if e != nil {
+		return &PathError{Op: "chmod", Path: name, Err: e}
+	}
+	return nil
+}
+*/
+
+// See docs in file.go:(*File).Chmod.
+func (f *File) chmod(mode FileMode) error {
+	/*
+		if err := f.checkValid("chmod"); err != nil {
+			return err
+		}
+		if e := f.pfd.Fchmod(syscallMode(mode)); e != nil {
+			return f.wrapErr("chmod", e)
+		}
+		return nil
+	*/
+	panic("todo: os.(*File).chmod")
+}
+
+// Chown changes the numeric uid and gid of the named file.
+// If there is an error, it will be of type *PathError.
+//
+// On Windows, it always returns the syscall.EWINDOWS error, wrapped
+// in *PathError.
+func (f *File) Chown(uid, gid int) error {
+	/*
+		if err := f.checkValid("chown"); err != nil {
+			return err
+		}
+		if e := f.pfd.Fchown(uid, gid); e != nil {
+			return f.wrapErr("chown", e)
+		}
+		return nil
+	*/
+	panic("todo: os.(*File).Chown")
+}
+
+// Truncate changes the size of the file.
+// It does not change the I/O offset.
+// If there is an error, it will be of type *PathError.
+func (f *File) Truncate(size int64) error {
+	/*
+		if err := f.checkValid("truncate"); err != nil {
+			return err
+		}
+		if e := f.pfd.Ftruncate(size); e != nil {
+			return f.wrapErr("truncate", e)
+		}
+		return nil
+	*/
+	panic("todo: os.(*File).Truncate")
+}
+
+// Sync commits the current contents of the file to stable storage.
+// Typically, this means flushing the file system's in-memory copy
+// of recently written data to disk.
+func (f *File) Sync() error {
+	/*
+		if err := f.checkValid("sync"); err != nil {
+			return err
+		}
+		if e := f.pfd.Fsync(); e != nil {
+			return f.wrapErr("sync", e)
+		}
+		return nil
+	*/
+	panic("todo: os.(*File).Sync")
+}
+
+/*
+// Chtimes changes the access and modification times of the named
+// file, similar to the Unix utime() or utimes() functions.
+// A zero time.Time value will leave the corresponding file time unchanged.
+//
+// The underlying filesystem may truncate or round the values to a
+// less precise time unit.
+// If there is an error, it will be of type *PathError.
+func Chtimes(name string, atime time.Time, mtime time.Time) error {
+	var utimes [2]syscall.Timespec
+	set := func(i int, t time.Time) {
+		if t.IsZero() {
+			utimes[i] = syscall.Timespec{Sec: _UTIME_OMIT, Nsec: _UTIME_OMIT}
+		} else {
+			utimes[i] = syscall.NsecToTimespec(t.UnixNano())
+		}
+	}
+	set(0, atime)
+	set(1, mtime)
+	if e := syscall.UtimesNano(fixLongPath(name), utimes[0:]); e != nil {
+		return &PathError{Op: "chtimes", Path: name, Err: e}
+	}
+	return nil
+}
+*/
+
+// Chdir changes the current working directory to the file,
+// which must be a directory.
+// If there is an error, it will be of type *PathError.
+func (f *File) Chdir() error {
+	/*
+		if err := f.checkValid("chdir"); err != nil {
+			return err
+		}
+		if e := f.pfd.Fchdir(); e != nil {
+			return f.wrapErr("chdir", e)
+		}
+		return nil
+	*/
+	panic("todo: os.(*File).Chdir")
+}
+
+// setDeadline sets the read and write deadline.
+func (f *File) setDeadline(t time.Time) error {
+	/*
+		if err := f.checkValid("SetDeadline"); err != nil {
+			return err
+		}
+		return f.pfd.SetDeadline(t)
+	*/
+	panic("todo: os.(*File).setDeadline")
+}
+
+// setReadDeadline sets the read deadline.
+func (f *File) setReadDeadline(t time.Time) error {
+	/*
+		if err := f.checkValid("SetReadDeadline"); err != nil {
+			return err
+		}
+		return f.pfd.SetReadDeadline(t)
+	*/
+	panic("todo: os.(*File).setReadDeadline")
+}
+
+// setWriteDeadline sets the write deadline.
+func (f *File) setWriteDeadline(t time.Time) error {
+	/*
+		if err := f.checkValid("SetWriteDeadline"); err != nil {
+			return err
+		}
+		return f.pfd.SetWriteDeadline(t)
+	*/
+	panic("todo: os.(*File).setWriteDeadline")
+}
+
+// checkValid checks whether f is valid for use.
+// If not, it returns an appropriate error, perhaps incorporating the operation name op.
+func (f *File) checkValid(op string) error {
+	if f == nil {
+		return ErrInvalid
+	}
+	return nil
+}
+
+// ignoringEINTR makes a function call and repeats it if it returns an
+// EINTR error. This appears to be required even though we install all
+// signal handlers with SA_RESTART: see #22838, #38033, #38836, #40846.
+// Also #20400 and #36644 are issues in which a signal handler is
+// installed without setting SA_RESTART. None of these are the common case,
+// but there are enough of them that it seems that we can't avoid
+// an EINTR loop.
+func ignoringEINTR(fn func() error) error {
+	for {
+		err := fn()
+		if err != syscall.EINTR {
+			return err
+		}
+	}
+}

internal/lib/os/os.go

@@ -120,6 +120,25 @@ func Chown(name string, uid, gid int) error {
 	return toPathErr("chown", name, ret)
 }
 
+/* TODO(xsw):
+// Chown changes the numeric uid and gid of the named file.
+// If the file is a symbolic link, it changes the uid and gid of the link's target.
+// A uid or gid of -1 means to not change that value.
+// If there is an error, it will be of type *PathError.
+//
+// On Windows or Plan 9, Chown always returns the syscall.EWINDOWS or
+// EPLAN9 error, wrapped in *PathError.
+func Chown(name string, uid, gid int) error {
+	e := ignoringEINTR(func() error {
+		return syscall.Chown(name, uid, gid)
+	})
+	if e != nil {
+		return &PathError{Op: "chown", Path: name, Err: e}
+	}
+	return nil
+}
+*/
+
 // TODO(xsw):
 // func Chtimes(name string, atime time.Time, mtime time.Time) error
 
@@ -195,6 +214,24 @@ func Lchown(name string, uid, gid int) error {
 	return toPathErr("lchown", name, ret)
 }
 
+/* TODO(xsw):
+// Lchown changes the numeric uid and gid of the named file.
+// If the file is a symbolic link, it changes the uid and gid of the link itself.
+// If there is an error, it will be of type *PathError.
+//
+// On Windows, it always returns the syscall.EWINDOWS error, wrapped
+// in *PathError.
+func Lchown(name string, uid, gid int) error {
+	e := ignoringEINTR(func() error {
+		return syscall.Lchown(name, uid, gid)
+	})
+	if e != nil {
+		return &PathError{Op: "lchown", Path: name, Err: e}
+	}
+	return nil
+}
+*/
+
 func Link(oldname, newname string) error {
 	ret := os.Link(c.AllocaCStr(oldname), c.AllocaCStr(newname))
 	if ret == 0 {

internal/lib/os/types.go

@@ -47,6 +47,16 @@ func (f *File) write(b []byte) (int, error) {
 	return 0, syscall.Errno(os.Errno)
 }
 
+/* TODO(xsw):
+// write writes len(b) bytes to the File.
+// It returns the number of bytes written and an error, if any.
+func (f *File) write(b []byte) (n int, err error) {
+	n, err = f.pfd.Write(b)
+	runtime.KeepAlive(f)
+	return n, err
+}
+*/
+
 // read reads up to len(b) bytes from the File.
 // It returns the number of bytes read and an error, if any.
 func (f *File) read(b []byte) (int, error) {
@@ -60,14 +70,15 @@ func (f *File) read(b []byte) (int, error) {
 	return 0, syscall.Errno(os.Errno)
 }
 
-// checkValid checks whether f is valid for use.
+/* TODO(xsw):
-// If not, it returns an appropriate error, perhaps incorporating the operation name op.
+// read reads up to len(b) bytes from the File.
-func (f *File) checkValid(op string) error {
+// It returns the number of bytes read and an error, if any.
-	if f == nil {
+func (f *File) read(b []byte) (n int, err error) {
-		return ErrInvalid
+	n, err = f.pfd.Read(b)
-	}
+	runtime.KeepAlive(f)
-	return nil
+	return n, err
 }
+*/
 
 // A FileInfo describes a file and is returned by Stat and Lstat.
 type FileInfo = fs.FileInfo