ggstd/os/

file_unix.rs

// Copyright 2023 The rust-ggstd authors.
// 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)

// package os

// import (
// 	"internal/poll"
// 	"internal/syscall/unix"
// 	"runtime"
// 	"syscall"
// 	_ "unsafe" // for go:linkname
// )

/// fix_long_path is a noop on non-Windows platforms.
pub fn fix_long_path(path: &str) -> String {
    path.to_string()
}

// fn rename(oldname, newname string) error {
// 	fi, err := Lstat(newname)
// 	if err == nil && fi.IsDir() {
// 		// There are two independent errors this function can return:
// 		// one for a bad oldname, and one for a bad newname.
// 		// At this point we've determined the newname is bad.
// 		// But just in case oldname is also bad, prioritize returning
// 		// the oldname error because that's what we did historically.
// 		// However, if the old name and new name are not the same, yet
// 		// they refer to the same file, it implies a case-only
// 		// rename on a case-insensitive filesystem, which is ok.
// 		if ofi, err := Lstat(oldname); err != nil {
// 			if pe, ok := err.(*PathError); ok {
// 				err = pe.Err
// 			}
// 			return &LinkError{"rename", oldname, newname, err}
// 		} else if newname == oldname || !SameFile(fi, ofi) {
// 			return &LinkError{"rename", oldname, newname, syscall.EEXIST}
// 		}
// 	}
// 	err = ignoringEINTR(fn() error {
// 		return syscall.Rename(oldname, newname)
// 	})
// 	if err != nil {
// 		return &LinkError{"rename", oldname, newname, err}
// 	}
// 	return nil
// }

// // file is the real representation of *File.
// // The extra level of indirection ensures that no clients of os
// // can overwrite this data, which could cause the finalizer
// // to close the wrong file descriptor.
// type file struct {
// 	pfd         poll.FD
// 	name        string
// 	dirinfo     *dirInfo // nil unless directory being read
// 	nonblock    bool     // whether we set nonblocking mode
// 	stdoutOrErr bool     // whether this is stdout or stderr
// 	appendMode  bool     // whether file is opened for appending
// }

// // Fd returns the integer Unix file descriptor referencing the open file.
// // If f is closed, the file descriptor becomes invalid.
// // If f is garbage collected, a finalizer may close the file descriptor,
// // making it invalid; see runtime.SetFinalizer for more information on when
// // a finalizer might be run. On Unix systems this will cause the SetDeadline
// // methods to stop working.
// // Because file descriptors can be reused, the returned file descriptor may
// // only be closed through the Close method of f, or by its finalizer during
// // garbage collection. Otherwise, during garbage collection the finalizer
// // may close an unrelated file descriptor with the same (reused) number.
// //
// // As an alternative, see the f.SyscallConn method.
// fn (f *File) Fd() uintptr {
// 	if f == nil {
// 		return ^(uintptr(0))
// 	}

// 	// If we put the file descriptor into nonblocking mode,
// 	// then set it to blocking mode before we return it,
// 	// because historically we have always returned a descriptor
// 	// opened in blocking mode. The File will continue to work,
// 	// but any blocking operation will tie up a thread.
// 	if f.nonblock {
// 		f.pfd.SetBlocking()
// 	}

// 	return uintptr(f.pfd.Sysfd)
// }

// // NewFile returns a new File with the given file descriptor and
// // name. The returned value will be nil if fd is not a valid file
// // descriptor. On Unix systems, if the file descriptor is in
// // non-blocking mode, NewFile will attempt to return a pollable File
// // (one for which the SetDeadline methods work).
// //
// // After passing it to NewFile, fd may become invalid under the same
// // conditions described in the comments of the Fd method, and the same
// // constraints apply.
// fn NewFile(fd uintptr, name string) *File {
// 	kind := kindNewFile
// 	if nb, err := unix.IsNonblock(int(fd)); err == nil && nb {
// 		kind = kindNonBlock
// 	}
// 	return newFile(fd, name, kind)
// }

// // net_newUnixFile is a hidden entry point called by net.conn.File.
// // This is used so that a nonblocking network connection will become
// // blocking if code calls the Fd method. We don't want that for direct
// // calls to NewFile: passing a nonblocking descriptor to NewFile should
// // remain nonblocking if you get it back using Fd. But for net.conn.File
// // the call to NewFile is hidden from the user. Historically in that case
// // the Fd method has returned a blocking descriptor, and we want to
// // retain that behavior because existing code expects it and depends on it.
// //
// //go:linkname net_newUnixFile net.newUnixFile
// fn net_newUnixFile(fd uintptr, name string) *File {
// 	f := newFile(fd, name, kindNonBlock)
// 	f.nonblock = true // tell Fd to return blocking descriptor
// 	return f
// }

// // newFileKind describes the kind of file to newFile.
// type newFileKind int

// const (
// 	kindNewFile newFileKind = iota
// 	kindOpenFile
// 	kindPipe
// 	kindNonBlock
// )

// // newFile is like NewFile, but if called from OpenFile or Pipe
// // (as passed in the kind parameter) it tries to add the file to
// // the runtime poller.
// fn newFile(fd uintptr, name string, kind newFileKind) *File {
// 	fdi := int(fd)
// 	if fdi < 0 {
// 		return nil
// 	}
// 	f := &File{&file{
// 		pfd: poll.FD{
// 			Sysfd:         fdi,
// 			IsStream:      true,
// 			ZeroReadIsEOF: true,
// 		},
// 		name:        name,
// 		stdoutOrErr: fdi == 1 || fdi == 2,
// 	}}

// 	pollable := kind == kindOpenFile || kind == kindPipe || kind == kindNonBlock

// 	// If the caller passed a non-blocking filedes (kindNonBlock),
// 	// we assume they know what they are doing so we allow it to be
// 	// used with kqueue.
// 	if kind == kindOpenFile {
// 		switch runtime.GOOS {
// 		case "darwin", "ios", "dragonfly", "freebsd", "netbsd", "openbsd":
// 			var st syscall.Stat_t
// 			err := ignoringEINTR(fn() error {
// 				return syscall.Fstat(fdi, &st)
// 			})
// 			typ := st.Mode & syscall.S_IFMT
// 			// Don't try to use kqueue with regular files on *BSDs.
// 			// On FreeBSD a regular file is always
// 			// reported as ready for writing.
// 			// On Dragonfly, NetBSD and OpenBSD the fd is signaled
// 			// only once as ready (both read and write).
// 			// Issue 19093.
// 			// Also don't add directories to the netpoller.
// 			if err == nil && (typ == syscall.S_IFREG || typ == syscall.S_IFDIR) {
// 				pollable = false
// 			}

// 			// In addition to the behavior described above for regular files,
// 			// on Darwin, kqueue does not work properly with fifos:
// 			// closing the last writer does not cause a kqueue event
// 			// for any readers. See issue #24164.
// 			if (runtime.GOOS == "darwin" || runtime.GOOS == "ios") && typ == syscall.S_IFIFO {
// 				pollable = false
// 			}
// 		}
// 	}

// 	clearNonBlock := false
// 	if pollable {
// 		if kind == kindNonBlock {
// 			// The descriptor is already in non-blocking mode.
// 			// We only set f.nonblock if we put the file into
// 			// non-blocking mode.
// 		} else if err := syscall.SetNonblock(fdi, true); err == nil {
// 			f.nonblock = true
// 			clearNonBlock = true
// 		} else {
// 			pollable = false
// 		}
// 	}

// 	// An error here indicates a failure to register
// 	// with the netpoll system. That can happen for
// 	// a file descriptor that is not supported by
// 	// epoll/kqueue; for example, disk files on
// 	// Linux systems. We assume that any real error
// 	// will show up in later I/O.
// 	// We do restore the blocking behavior if it was set by us.
// 	if pollErr := f.pfd.Init("file", pollable); pollErr != nil && clearNonBlock {
// 		if err := syscall.SetNonblock(fdi, false); err == nil {
// 			f.nonblock = false
// 		}
// 	}

// 	runtime.SetFinalizer(f.file, (*file).close)
// 	return f
// }

// // epipecheck raises SIGPIPE if we get an EPIPE error on standard
// // output or standard error. See the SIGPIPE docs in os/signal, and
// // issue 11845.
// fn epipecheck(file *File, e error) {
// 	if e == syscall.EPIPE && file.stdoutOrErr {
// 		sigpipe()
// 	}
// }

// // DevNull is the name of the operating system's “null device.”
// // On Unix-like systems, it is "/dev/null"; on Windows, "NUL".
// const DevNull = "/dev/null"

// // openFileNolog is the Unix implementation of OpenFile.
// // Changes here should be reflected in openFdAt, if relevant.
// fn openFileNolog(name string, flag int, perm FileMode) (*File, error) {
// 	setSticky := false
// 	if !supportsCreateWithStickyBit && flag&O_CREATE != 0 && perm&ModeSticky != 0 {
// 		if _, err := Stat(name); IsNotExist(err) {
// 			setSticky = true
// 		}
// 	}

// 	var r int
// 	for {
// 		var e error
// 		r, e = syscall.Open(name, flag|syscall.O_CLOEXEC, syscallMode(perm))
// 		if e == nil {
// 			break
// 		}

// 		// We have to check EINTR here, per issues 11180 and 39237.
// 		if e == syscall.EINTR {
// 			continue
// 		}

// 		return nil, &PathError{Op: "open", Path: name, Err: e}
// 	}

// 	// open(2) itself won't handle the sticky bit on *BSD and Solaris
// 	if setSticky {
// 		setStickyBit(name)
// 	}

// 	// There's a race here with fork/exec, which we are
// 	// content to live with. See ../syscall/exec_unix.go.
// 	if !supportsCloseOnExec {
// 		syscall.CloseOnExec(r)
// 	}

// 	kind := kindOpenFile
// 	if unix.HasNonblockFlag(flag) {
// 		kind = kindNonBlock
// 	}

// 	return newFile(uintptr(r), name, kind), nil
// }

// fn (file *file) close() error {
// 	if file == nil {
// 		return syscall.EINVAL
// 	}
// 	if file.dirinfo != nil {
// 		file.dirinfo.close()
// 		file.dirinfo = nil
// 	}
// 	var err error
// 	if e := file.pfd.Close(); e != nil {
// 		if e == poll.ErrFileClosing {
// 			e = ErrClosed
// 		}
// 		err = &PathError{Op: "close", Path: file.name, Err: e}
// 	}

// 	// no need for a finalizer anymore
// 	runtime.SetFinalizer(file, nil)
// 	return err
// }

// // 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.
// fn (f *File) seek(offset int64, whence int) (ret int64, err error) {
// 	if f.dirinfo != nil {
// 		// Free cached dirinfo, so we allocate a new one if we
// 		// access this file as a directory again. See #35767 and #37161.
// 		f.dirinfo.close()
// 		f.dirinfo = nil
// 	}
// 	ret, err = f.pfd.Seek(offset, whence)
// 	runtime.KeepAlive(f)
// 	return ret, err
// }

// // Truncate changes the size of the named file.
// // If the file is a symbolic link, it changes the size of the link's target.
// // If there is an error, it will be of type *PathError.
// fn Truncate(name string, size int64) error {
// 	e := ignoringEINTR(fn() error {
// 		return syscall.Truncate(name, size)
// 	})
// 	if e != nil {
// 		return &PathError{Op: "truncate", Path: name, Err: e}
// 	}
// 	return nil
// }

// // Remove removes the named file or (empty) directory.
// // If there is an error, it will be of type *PathError.
// fn Remove(name string) error {
// 	// System call interface forces us to know
// 	// whether name is a file or directory.
// 	// Try both: it is cheaper on average than
// 	// doing a Stat plus the right one.
// 	e := ignoringEINTR(fn() error {
// 		return syscall.Unlink(name)
// 	})
// 	if e == nil {
// 		return nil
// 	}
// 	e1 := ignoringEINTR(fn() error {
// 		return syscall.Rmdir(name)
// 	})
// 	if e1 == nil {
// 		return nil
// 	}

// 	// Both failed: figure out which error to return.
// 	// OS X and Linux differ on whether unlink(dir)
// 	// returns EISDIR, so can't use that. However,
// 	// both agree that rmdir(file) returns ENOTDIR,
// 	// so we can use that to decide which error is real.
// 	// Rmdir might also return ENOTDIR if given a bad
// 	// file path, like /etc/passwd/foo, but in that case,
// 	// both errors will be ENOTDIR, so it's okay to
// 	// use the error from unlink.
// 	if e1 != syscall.ENOTDIR {
// 		e = e1
// 	}
// 	return &PathError{Op: "remove", Path: name, Err: e}
// }

// fn tempDir() string {
// 	dir := Getenv("TMPDIR")
// 	if dir == "" {
// 		if runtime.GOOS == "android" {
// 			dir = "/data/local/tmp"
// 		} else {
// 			dir = "/tmp"
// 		}
// 	}
// 	return dir
// }

// // Link creates newname as a hard link to the oldname file.
// // If there is an error, it will be of type *LinkError.
// fn Link(oldname, newname string) error {
// 	e := ignoringEINTR(fn() error {
// 		return syscall.Link(oldname, newname)
// 	})
// 	if e != nil {
// 		return &LinkError{"link", oldname, newname, e}
// 	}
// 	return nil
// }

// // Symlink creates newname as a symbolic link to oldname.
// // On Windows, a symlink to a non-existent oldname creates a file symlink;
// // if oldname is later created as a directory the symlink will not work.
// // If there is an error, it will be of type *LinkError.
// fn Symlink(oldname, newname string) error {
// 	e := ignoringEINTR(fn() error {
// 		return syscall.Symlink(oldname, newname)
// 	})
// 	if e != nil {
// 		return &LinkError{"symlink", oldname, newname, e}
// 	}
// 	return nil
// }

// // Readlink returns the destination of the named symbolic link.
// // If there is an error, it will be of type *PathError.
// fn Readlink(name string) (string, error) {
// 	for len := 128; ; len *= 2 {
// 		b := make([]byte, len)
// 		var (
// 			n int
// 			e error
// 		)
// 		for {
// 			n, e = fixCount(syscall.Readlink(name, b))
// 			if e != syscall.EINTR {
// 				break
// 			}
// 		}
// 		// buffer too small
// 		if runtime.GOOS == "aix" && e == syscall.ERANGE {
// 			continue
// 		}
// 		if e != nil {
// 			return "", &PathError{Op: "readlink", Path: name, Err: e}
// 		}
// 		if n < len {
// 			return string(b[0:n]), nil
// 		}
// 	}
// }

// type unixDirent struct {
// 	parent string
// 	name   string
// 	typ    FileMode
// 	info   FileInfo
// }

// fn (d *unixDirent) Name() string   { return d.name }
// fn (d *unixDirent) IsDir() bool    { return d.typ.IsDir() }
// fn (d *unixDirent) Type() FileMode { return d.typ }

// fn (d *unixDirent) Info() (FileInfo, error) {
// 	if d.info != nil {
// 		return d.info, nil
// 	}
// 	return lstat(d.parent + "/" + d.name)
// }

// fn newUnixDirent(parent, name string, typ FileMode) (DirEntry, error) {
// 	ude := &unixDirent{
// 		parent: parent,
// 		name:   name,
// 		typ:    typ,
// 	}
// 	if typ != ^FileMode(0) && !testingForceReadDirLstat {
// 		return ude, nil
// 	}

// 	info, err := lstat(parent + "/" + name)
// 	if err != nil {
// 		return nil, err
// 	}

// 	ude.typ = info.Mode().Type()
// 	ude.info = info
// 	return ude, nil
// }