123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250 |
- // 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 aix || darwin || dragonfly || freebsd || hurd || (js && wasm) || linux || netbsd || openbsd || solaris || 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
- }
- }
- }
|