1 files changed, 427 insertions, 0 deletions
diff --git a/src/syscall/syscall_plan9.go b/src/syscall/syscall_plan9.go
new file mode 100644
index 0000000..d16cad4
--- /dev/null
+++ b/src/syscall/syscall_plan9.go
@@ -0,0 +1,427 @@
+// Copyright 2011 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.
+
+// Plan 9 system calls.
+// This file is compiled as ordinary Go code,
+// but it is also input to mksyscall,
+// which parses the //sys lines and generates system call stubs.
+// Note that sometimes we use a lowercase //sys name and
+// wrap it in our own nicer implementation.
+
+package syscall
+
+import (
+	"internal/oserror"
+	"unsafe"
+)
+
+const ImplementsGetwd = true
+const bitSize16 = 2
+
+// ErrorString implements Error's String method by returning itself.
+//
+// ErrorString values can be tested against error values from the os package
+// using errors.Is. For example:
+//
+//	_, _, err := syscall.Syscall(...)
+//	if errors.Is(err, fs.ErrNotExist) ...
+type ErrorString string
+
+func (e ErrorString) Error() string { return string(e) }
+
+// NewError converts s to an ErrorString, which satisfies the Error interface.
+func NewError(s string) error { return ErrorString(s) }
+
+func (e ErrorString) Is(target error) bool {
+	switch target {
+	case oserror.ErrPermission:
+		return checkErrMessageContent(e, "permission denied")
+	case oserror.ErrExist:
+		return checkErrMessageContent(e, "exists", "is a directory")
+	case oserror.ErrNotExist:
+		return checkErrMessageContent(e, "does not exist", "not found",
+			"has been removed", "no parent")
+	}
+	return false
+}
+
+// checkErrMessageContent checks if err message contains one of msgs.
+func checkErrMessageContent(e ErrorString, msgs ...string) bool {
+	for _, msg := range msgs {
+		if contains(string(e), msg) {
+			return true
+		}
+	}
+	return false
+}
+
+// contains is a local version of strings.Contains. It knows len(sep) > 1.
+func contains(s, sep string) bool {
+	n := len(sep)
+	c := sep[0]
+	for i := 0; i+n <= len(s); i++ {
+		if s[i] == c && s[i:i+n] == sep {
+			return true
+		}
+	}
+	return false
+}
+
+func (e ErrorString) Temporary() bool {
+	return e == EINTR || e == EMFILE || e.Timeout()
+}
+
+func (e ErrorString) Timeout() bool {
+	return e == EBUSY || e == ETIMEDOUT
+}
+
+var emptystring string
+
+// A Note is a string describing a process note.
+// It implements the os.Signal interface.
+type Note string
+
+func (n Note) Signal() {}
+
+func (n Note) String() string {
+	return string(n)
+}
+
+var (
+	Stdin  = 0
+	Stdout = 1
+	Stderr = 2
+)
+
+// For testing: clients can set this flag to force
+// creation of IPv6 sockets to return EAFNOSUPPORT.
+var SocketDisableIPv6 bool
+
+func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err ErrorString)
+func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err ErrorString)
+func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2, err uintptr)
+func RawSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr)
+
+//go:nosplit
+func atoi(b []byte) (n uint) {
+	n = 0
+	for i := 0; i < len(b); i++ {
+		n = n*10 + uint(b[i]-'0')
+	}
+	return
+}
+
+func cstring(s []byte) string {
+	for i := range s {
+		if s[i] == 0 {
+			return string(s[0:i])
+		}
+	}
+	return string(s)
+}
+
+func errstr() string {
+	var buf [ERRMAX]byte
+
+	RawSyscall(SYS_ERRSTR, uintptr(unsafe.Pointer(&buf[0])), uintptr(len(buf)), 0)
+
+	buf[len(buf)-1] = 0
+	return cstring(buf[:])
+}
+
+func readnum(path string) (uint, error) {
+	var b [12]byte
+
+	fd, e := Open(path, O_RDONLY)
+	if e != nil {
+		return 0, e
+	}
+	defer Close(fd)
+
+	n, e := Pread(fd, b[:], 0)
+
+	if e != nil {
+		return 0, e
+	}
+
+	m := 0
+	for ; m < n && b[m] == ' '; m++ {
+	}
+
+	return atoi(b[m : n-1]), nil
+}
+
+func Getpid() (pid int) {
+	n, _ := readnum("#c/pid")
+	return int(n)
+}
+
+func Getppid() (ppid int) {
+	n, _ := readnum("#c/ppid")
+	return int(n)
+}
+
+func Read(fd int, p []byte) (n int, err error) {
+	return Pread(fd, p, -1)
+}
+
+func Write(fd int, p []byte) (n int, err error) {
+	if faketime && (fd == 1 || fd == 2) {
+		n = faketimeWrite(fd, p)
+		if n < 0 {
+			return 0, ErrorString("error")
+		}
+		return n, nil
+	}
+
+	return Pwrite(fd, p, -1)
+}
+
+var ioSync int64
+
+//sys	fd2path(fd int, buf []byte) (err error)
+func Fd2path(fd int) (path string, err error) {
+	var buf [512]byte
+
+	e := fd2path(fd, buf[:])
+	if e != nil {
+		return "", e
+	}
+	return cstring(buf[:]), nil
+}
+
+//sys	pipe(p *[2]int32) (err error)
+func Pipe(p []int) (err error) {
+	if len(p) != 2 {
+		return NewError("bad arg in system call")
+	}
+	var pp [2]int32
+	err = pipe(&pp)
+	p[0] = int(pp[0])
+	p[1] = int(pp[1])
+	return
+}
+
+// Underlying system call writes to newoffset via pointer.
+// Implemented in assembly to avoid allocation.
+func seek(placeholder uintptr, fd int, offset int64, whence int) (newoffset int64, err string)
+
+func Seek(fd int, offset int64, whence int) (newoffset int64, err error) {
+	newoffset, e := seek(0, fd, offset, whence)
+
+	if newoffset == -1 {
+		err = NewError(e)
+	}
+	return
+}
+
+func Mkdir(path string, mode uint32) (err error) {
+	// If path exists and is not a directory, Create will fail silently.
+	// Work around this by rejecting Mkdir if path exists.
+	statbuf := make([]byte, bitSize16)
+	// Remove any trailing slashes from path, otherwise the Stat will
+	// fail with ENOTDIR.
+	n := len(path)
+	for n > 1 && path[n-1] == '/' {
+		n--
+	}
+	_, err = Stat(path[0:n], statbuf)
+	if err == nil {
+		return EEXIST
+	}
+
+	fd, err := Create(path, O_RDONLY, DMDIR|mode)
+
+	if fd != -1 {
+		Close(fd)
+	}
+
+	return
+}
+
+type Waitmsg struct {
+	Pid  int
+	Time [3]uint32
+	Msg  string
+}
+
+func (w Waitmsg) Exited() bool   { return true }
+func (w Waitmsg) Signaled() bool { return false }
+
+func (w Waitmsg) ExitStatus() int {
+	if len(w.Msg) == 0 {
+		// a normal exit returns no message
+		return 0
+	}
+	return 1
+}
+
+//sys	await(s []byte) (n int, err error)
+func Await(w *Waitmsg) (err error) {
+	var buf [512]byte
+	var f [5][]byte
+
+	n, err := await(buf[:])
+
+	if err != nil || w == nil {
+		return
+	}
+
+	nf := 0
+	p := 0
+	for i := 0; i < n && nf < len(f)-1; i++ {
+		if buf[i] == ' ' {
+			f[nf] = buf[p:i]
+			p = i + 1
+			nf++
+		}
+	}
+	f[nf] = buf[p:]
+	nf++
+
+	if nf != len(f) {
+		return NewError("invalid wait message")
+	}
+	w.Pid = int(atoi(f[0]))
+	w.Time[0] = uint32(atoi(f[1]))
+	w.Time[1] = uint32(atoi(f[2]))
+	w.Time[2] = uint32(atoi(f[3]))
+	w.Msg = cstring(f[4])
+	if w.Msg == "''" {
+		// await() returns '' for no error
+		w.Msg = ""
+	}
+	return
+}
+
+func Unmount(name, old string) (err error) {
+	fixwd(name, old)
+	oldp, err := BytePtrFromString(old)
+	if err != nil {
+		return err
+	}
+	oldptr := uintptr(unsafe.Pointer(oldp))
+
+	var r0 uintptr
+	var e ErrorString
+
+	// bind(2) man page: If name is zero, everything bound or mounted upon old is unbound or unmounted.
+	if name == "" {
+		r0, _, e = Syscall(SYS_UNMOUNT, _zero, oldptr, 0)
+	} else {
+		namep, err := BytePtrFromString(name)
+		if err != nil {
+			return err
+		}
+		r0, _, e = Syscall(SYS_UNMOUNT, uintptr(unsafe.Pointer(namep)), oldptr, 0)
+	}
+
+	if int32(r0) == -1 {
+		err = e
+	}
+	return
+}
+
+func Fchdir(fd int) (err error) {
+	path, err := Fd2path(fd)
+
+	if err != nil {
+		return
+	}
+
+	return Chdir(path)
+}
+
+type Timespec struct {
+	Sec  int32
+	Nsec int32
+}
+
+type Timeval struct {
+	Sec  int32
+	Usec int32
+}
+
+func NsecToTimeval(nsec int64) (tv Timeval) {
+	nsec += 999 // round up to microsecond
+	tv.Usec = int32(nsec % 1e9 / 1e3)
+	tv.Sec = int32(nsec / 1e9)
+	return
+}
+
+func nsec() int64 {
+	var scratch int64
+
+	r0, _, _ := Syscall(SYS_NSEC, uintptr(unsafe.Pointer(&scratch)), 0, 0)
+	// TODO(aram): remove hack after I fix _nsec in the pc64 kernel.
+	if r0 == 0 {
+		return scratch
+	}
+	return int64(r0)
+}
+
+func Gettimeofday(tv *Timeval) error {
+	nsec := nsec()
+	*tv = NsecToTimeval(nsec)
+	return nil
+}
+
+func Getegid() (egid int) { return -1 }
+func Geteuid() (euid int) { return -1 }
+func Getgid() (gid int)   { return -1 }
+func Getuid() (uid int)   { return -1 }
+
+func Getgroups() (gids []int, err error) {
+	return make([]int, 0), nil
+}
+
+//sys	open(path string, mode int) (fd int, err error)
+func Open(path string, mode int) (fd int, err error) {
+	fixwd(path)
+	return open(path, mode)
+}
+
+//sys	create(path string, mode int, perm uint32) (fd int, err error)
+func Create(path string, mode int, perm uint32) (fd int, err error) {
+	fixwd(path)
+	return create(path, mode, perm)
+}
+
+//sys	remove(path string) (err error)
+func Remove(path string) error {
+	fixwd(path)
+	return remove(path)
+}
+
+//sys	stat(path string, edir []byte) (n int, err error)
+func Stat(path string, edir []byte) (n int, err error) {
+	fixwd(path)
+	return stat(path, edir)
+}
+
+//sys	bind(name string, old string, flag int) (err error)
+func Bind(name string, old string, flag int) (err error) {
+	fixwd(name, old)
+	return bind(name, old, flag)
+}
+
+//sys	mount(fd int, afd int, old string, flag int, aname string) (err error)
+func Mount(fd int, afd int, old string, flag int, aname string) (err error) {
+	fixwd(old)
+	return mount(fd, afd, old, flag, aname)
+}
+
+//sys	wstat(path string, edir []byte) (err error)
+func Wstat(path string, edir []byte) (err error) {
+	fixwd(path)
+	return wstat(path, edir)
+}
+
+//sys	chdir(path string) (err error)
+//sys	Dup(oldfd int, newfd int) (fd int, err error)
+//sys	Pread(fd int, p []byte, offset int64) (n int, err error)
+//sys	Pwrite(fd int, p []byte, offset int64) (n int, err error)
+//sys	Close(fd int) (err error)
+//sys	Fstat(fd int, edir []byte) (n int, err error)
+//sys	Fwstat(fd int, edir []byte) (err error)