1 files changed, 250 insertions, 0 deletions
diff --git a/src/os/file_posix.go b/src/os/file_posix.go
new file mode 100644
index 0000000..c6d18ff
--- /dev/null
+++ b/src/os/file_posix.go
@@ -0,0 +1,250 @@
+// 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) || windows
+
+package os
+
+import (
+	"runtime"
+	"syscall"
+	"time"
+)
+
+func sigpipe() // implemented in package runtime
+
+// 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()
+}
+
+// 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) (n int, err error) {
+	n, err = f.pfd.Read(b)
+	runtime.KeepAlive(f)
+	return n, err
+}
+
+// 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
+}
+
+// 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
+}
+
+// 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
+}
+
+// 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
+}
+
+// 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
+}
+
+// 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
+}
+
+// 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
+}
+
+// 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
+}
+
+// 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
+}
+
+// Chtimes changes the access and modification times of the named
+// file, similar to the Unix utime() or utimes() functions.
+//
+// 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
+	utimes[0] = syscall.NsecToTimespec(atime.UnixNano())
+	utimes[1] = syscall.NsecToTimespec(mtime.UnixNano())
+	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
+}
+
+// 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)
+}
+
+// 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)
+}
+
+// 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)
+}
+
+// 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
+		}
+	}
+}