1// Copyright 2009 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5//go:build darwin || dragonfly || freebsd || netbsd || openbsd
6
7// BSD system call wrappers shared by *BSD based systems
8// including OS X (Darwin) and FreeBSD.  Like the other
9// syscall_*.go files it is compiled as Go code but also
10// used as input to mksyscall which parses the //sys
11// lines and generates system call stubs.
12
13package syscall
14
15import (
16	"runtime"
17	"unsafe"
18)
19
20const ImplementsGetwd = true
21
22func Getwd() (string, error) {
23	var buf [pathMax]byte
24	_, err := getcwd(buf[:])
25	if err != nil {
26		return "", err
27	}
28	n := clen(buf[:])
29	if n < 1 {
30		return "", EINVAL
31	}
32	return string(buf[:n]), nil
33}
34
35/*
36 * Wrapped
37 */
38
39//sysnb	getgroups(ngid int, gid *_Gid_t) (n int, err error)
40//sysnb	setgroups(ngid int, gid *_Gid_t) (err error)
41
42func Getgroups() (gids []int, err error) {
43	n, err := getgroups(0, nil)
44	if err != nil {
45		return nil, err
46	}
47	if n == 0 {
48		return nil, nil
49	}
50
51	// Sanity check group count. Max is 16 on BSD.
52	if n < 0 || n > 1000 {
53		return nil, EINVAL
54	}
55
56	a := make([]_Gid_t, n)
57	n, err = getgroups(n, &a[0])
58	if err != nil {
59		return nil, err
60	}
61	gids = make([]int, n)
62	for i, v := range a[0:n] {
63		gids[i] = int(v)
64	}
65	return
66}
67
68func Setgroups(gids []int) (err error) {
69	if len(gids) == 0 {
70		return setgroups(0, nil)
71	}
72
73	a := make([]_Gid_t, len(gids))
74	for i, v := range gids {
75		a[i] = _Gid_t(v)
76	}
77	return setgroups(len(a), &a[0])
78}
79
80func ReadDirent(fd int, buf []byte) (n int, err error) {
81	// Final argument is (basep *uintptr) and the syscall doesn't take nil.
82	// 64 bits should be enough. (32 bits isn't even on 386). Since the
83	// actual system call is getdirentries64, 64 is a good guess.
84	// TODO(rsc): Can we use a single global basep for all calls?
85	var base = (*uintptr)(unsafe.Pointer(new(uint64)))
86	return Getdirentries(fd, buf, base)
87}
88
89// Wait status is 7 bits at bottom, either 0 (exited),
90// 0x7F (stopped), or a signal number that caused an exit.
91// The 0x80 bit is whether there was a core dump.
92// An extra number (exit code, signal causing a stop)
93// is in the high bits.
94
95type WaitStatus uint32
96
97const (
98	mask  = 0x7F
99	core  = 0x80
100	shift = 8
101
102	exited  = 0
103	stopped = 0x7F
104)
105
106func (w WaitStatus) Exited() bool { return w&mask == exited }
107
108func (w WaitStatus) ExitStatus() int {
109	if w&mask != exited {
110		return -1
111	}
112	return int(w >> shift)
113}
114
115func (w WaitStatus) Signaled() bool { return w&mask != stopped && w&mask != 0 }
116
117func (w WaitStatus) Signal() Signal {
118	sig := Signal(w & mask)
119	if sig == stopped || sig == 0 {
120		return -1
121	}
122	return sig
123}
124
125func (w WaitStatus) CoreDump() bool { return w.Signaled() && w&core != 0 }
126
127func (w WaitStatus) Stopped() bool { return w&mask == stopped && Signal(w>>shift) != SIGSTOP }
128
129func (w WaitStatus) Continued() bool { return w&mask == stopped && Signal(w>>shift) == SIGSTOP }
130
131func (w WaitStatus) StopSignal() Signal {
132	if !w.Stopped() {
133		return -1
134	}
135	return Signal(w>>shift) & 0xFF
136}
137
138func (w WaitStatus) TrapCause() int { return -1 }
139
140//sys	wait4(pid int, wstatus *_C_int, options int, rusage *Rusage) (wpid int, err error)
141
142func Wait4(pid int, wstatus *WaitStatus, options int, rusage *Rusage) (wpid int, err error) {
143	var status _C_int
144	wpid, err = wait4(pid, &status, options, rusage)
145	if wstatus != nil {
146		*wstatus = WaitStatus(status)
147	}
148	return
149}
150
151//sys	accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, err error)
152//sys	bind(s int, addr unsafe.Pointer, addrlen _Socklen) (err error)
153//sys	connect(s int, addr unsafe.Pointer, addrlen _Socklen) (err error)
154//sysnb	socket(domain int, typ int, proto int) (fd int, err error)
155//sys	getsockopt(s int, level int, name int, val unsafe.Pointer, vallen *_Socklen) (err error)
156//sys	setsockopt(s int, level int, name int, val unsafe.Pointer, vallen uintptr) (err error)
157//sysnb	getpeername(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error)
158//sysnb	getsockname(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error)
159//sys	Shutdown(s int, how int) (err error)
160
161func (sa *SockaddrInet4) sockaddr() (unsafe.Pointer, _Socklen, error) {
162	if sa.Port < 0 || sa.Port > 0xFFFF {
163		return nil, 0, EINVAL
164	}
165	sa.raw.Len = SizeofSockaddrInet4
166	sa.raw.Family = AF_INET
167	p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port))
168	p[0] = byte(sa.Port >> 8)
169	p[1] = byte(sa.Port)
170	sa.raw.Addr = sa.Addr
171	return unsafe.Pointer(&sa.raw), _Socklen(sa.raw.Len), nil
172}
173
174func (sa *SockaddrInet6) sockaddr() (unsafe.Pointer, _Socklen, error) {
175	if sa.Port < 0 || sa.Port > 0xFFFF {
176		return nil, 0, EINVAL
177	}
178	sa.raw.Len = SizeofSockaddrInet6
179	sa.raw.Family = AF_INET6
180	p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port))
181	p[0] = byte(sa.Port >> 8)
182	p[1] = byte(sa.Port)
183	sa.raw.Scope_id = sa.ZoneId
184	sa.raw.Addr = sa.Addr
185	return unsafe.Pointer(&sa.raw), _Socklen(sa.raw.Len), nil
186}
187
188func (sa *SockaddrUnix) sockaddr() (unsafe.Pointer, _Socklen, error) {
189	name := sa.Name
190	n := len(name)
191	if n >= len(sa.raw.Path) || n == 0 {
192		return nil, 0, EINVAL
193	}
194	sa.raw.Len = byte(3 + n) // 2 for Family, Len; 1 for NUL
195	sa.raw.Family = AF_UNIX
196	for i := 0; i < n; i++ {
197		sa.raw.Path[i] = int8(name[i])
198	}
199	return unsafe.Pointer(&sa.raw), _Socklen(sa.raw.Len), nil
200}
201
202func (sa *SockaddrDatalink) sockaddr() (unsafe.Pointer, _Socklen, error) {
203	if sa.Index == 0 {
204		return nil, 0, EINVAL
205	}
206	sa.raw.Len = sa.Len
207	sa.raw.Family = AF_LINK
208	sa.raw.Index = sa.Index
209	sa.raw.Type = sa.Type
210	sa.raw.Nlen = sa.Nlen
211	sa.raw.Alen = sa.Alen
212	sa.raw.Slen = sa.Slen
213	sa.raw.Data = sa.Data
214	return unsafe.Pointer(&sa.raw), SizeofSockaddrDatalink, nil
215}
216
217func anyToSockaddr(rsa *RawSockaddrAny) (Sockaddr, error) {
218	switch rsa.Addr.Family {
219	case AF_LINK:
220		pp := (*RawSockaddrDatalink)(unsafe.Pointer(rsa))
221		sa := new(SockaddrDatalink)
222		sa.Len = pp.Len
223		sa.Family = pp.Family
224		sa.Index = pp.Index
225		sa.Type = pp.Type
226		sa.Nlen = pp.Nlen
227		sa.Alen = pp.Alen
228		sa.Slen = pp.Slen
229		sa.Data = pp.Data
230		return sa, nil
231
232	case AF_UNIX:
233		pp := (*RawSockaddrUnix)(unsafe.Pointer(rsa))
234		if pp.Len < 2 || pp.Len > SizeofSockaddrUnix {
235			return nil, EINVAL
236		}
237		sa := new(SockaddrUnix)
238
239		// Some BSDs include the trailing NUL in the length, whereas
240		// others do not. Work around this by subtracting the leading
241		// family and len. The path is then scanned to see if a NUL
242		// terminator still exists within the length.
243		n := int(pp.Len) - 2 // subtract leading Family, Len
244		for i := 0; i < n; i++ {
245			if pp.Path[i] == 0 {
246				// found early NUL; assume Len included the NUL
247				// or was overestimating.
248				n = i
249				break
250			}
251		}
252		sa.Name = string(unsafe.Slice((*byte)(unsafe.Pointer(&pp.Path[0])), n))
253		return sa, nil
254
255	case AF_INET:
256		pp := (*RawSockaddrInet4)(unsafe.Pointer(rsa))
257		sa := new(SockaddrInet4)
258		p := (*[2]byte)(unsafe.Pointer(&pp.Port))
259		sa.Port = int(p[0])<<8 + int(p[1])
260		sa.Addr = pp.Addr
261		return sa, nil
262
263	case AF_INET6:
264		pp := (*RawSockaddrInet6)(unsafe.Pointer(rsa))
265		sa := new(SockaddrInet6)
266		p := (*[2]byte)(unsafe.Pointer(&pp.Port))
267		sa.Port = int(p[0])<<8 + int(p[1])
268		sa.ZoneId = pp.Scope_id
269		sa.Addr = pp.Addr
270		return sa, nil
271	}
272	return nil, EAFNOSUPPORT
273}
274
275func Accept(fd int) (nfd int, sa Sockaddr, err error) {
276	var rsa RawSockaddrAny
277	var len _Socklen = SizeofSockaddrAny
278	nfd, err = accept(fd, &rsa, &len)
279	if err != nil {
280		return
281	}
282	if (runtime.GOOS == "darwin" || runtime.GOOS == "ios") && len == 0 {
283		// Accepted socket has no address.
284		// This is likely due to a bug in xnu kernels,
285		// where instead of ECONNABORTED error socket
286		// is accepted, but has no address.
287		Close(nfd)
288		return 0, nil, ECONNABORTED
289	}
290	sa, err = anyToSockaddr(&rsa)
291	if err != nil {
292		Close(nfd)
293		nfd = 0
294	}
295	return
296}
297
298func Getsockname(fd int) (sa Sockaddr, err error) {
299	var rsa RawSockaddrAny
300	var len _Socklen = SizeofSockaddrAny
301	if err = getsockname(fd, &rsa, &len); err != nil {
302		return
303	}
304	// TODO(jsing): DragonFly has a "bug" (see issue 3349), which should be
305	// reported upstream.
306	if runtime.GOOS == "dragonfly" && rsa.Addr.Family == AF_UNSPEC && rsa.Addr.Len == 0 {
307		rsa.Addr.Family = AF_UNIX
308		rsa.Addr.Len = SizeofSockaddrUnix
309	}
310	return anyToSockaddr(&rsa)
311}
312
313//sysnb socketpair(domain int, typ int, proto int, fd *[2]int32) (err error)
314
315func GetsockoptByte(fd, level, opt int) (value byte, err error) {
316	var n byte
317	vallen := _Socklen(1)
318	err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen)
319	return n, err
320}
321
322func GetsockoptInet4Addr(fd, level, opt int) (value [4]byte, err error) {
323	vallen := _Socklen(4)
324	err = getsockopt(fd, level, opt, unsafe.Pointer(&value[0]), &vallen)
325	return value, err
326}
327
328func GetsockoptIPMreq(fd, level, opt int) (*IPMreq, error) {
329	var value IPMreq
330	vallen := _Socklen(SizeofIPMreq)
331	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
332	return &value, err
333}
334
335func GetsockoptIPv6Mreq(fd, level, opt int) (*IPv6Mreq, error) {
336	var value IPv6Mreq
337	vallen := _Socklen(SizeofIPv6Mreq)
338	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
339	return &value, err
340}
341
342func GetsockoptIPv6MTUInfo(fd, level, opt int) (*IPv6MTUInfo, error) {
343	var value IPv6MTUInfo
344	vallen := _Socklen(SizeofIPv6MTUInfo)
345	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
346	return &value, err
347}
348
349func GetsockoptICMPv6Filter(fd, level, opt int) (*ICMPv6Filter, error) {
350	var value ICMPv6Filter
351	vallen := _Socklen(SizeofICMPv6Filter)
352	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
353	return &value, err
354}
355
356//sys   recvfrom(fd int, p []byte, flags int, from *RawSockaddrAny, fromlen *_Socklen) (n int, err error)
357//sys   sendto(s int, buf []byte, flags int, to unsafe.Pointer, addrlen _Socklen) (err error)
358//sys	recvmsg(s int, msg *Msghdr, flags int) (n int, err error)
359
360func recvmsgRaw(fd int, p, oob []byte, flags int, rsa *RawSockaddrAny) (n, oobn int, recvflags int, err error) {
361	var msg Msghdr
362	msg.Name = (*byte)(unsafe.Pointer(rsa))
363	msg.Namelen = uint32(SizeofSockaddrAny)
364	var iov Iovec
365	if len(p) > 0 {
366		iov.Base = &p[0]
367		iov.SetLen(len(p))
368	}
369	var dummy byte
370	if len(oob) > 0 {
371		// receive at least one normal byte
372		if len(p) == 0 {
373			iov.Base = &dummy
374			iov.SetLen(1)
375		}
376		msg.Control = &oob[0]
377		msg.SetControllen(len(oob))
378	}
379	msg.Iov = &iov
380	msg.Iovlen = 1
381	if n, err = recvmsg(fd, &msg, flags); err != nil {
382		return
383	}
384	oobn = int(msg.Controllen)
385	recvflags = int(msg.Flags)
386	return
387}
388
389//sys	sendmsg(s int, msg *Msghdr, flags int) (n int, err error)
390
391func sendmsgN(fd int, p, oob []byte, ptr unsafe.Pointer, salen _Socklen, flags int) (n int, err error) {
392	var msg Msghdr
393	msg.Name = (*byte)(ptr)
394	msg.Namelen = uint32(salen)
395	var iov Iovec
396	if len(p) > 0 {
397		iov.Base = &p[0]
398		iov.SetLen(len(p))
399	}
400	var dummy byte
401	if len(oob) > 0 {
402		// send at least one normal byte
403		if len(p) == 0 {
404			iov.Base = &dummy
405			iov.SetLen(1)
406		}
407		msg.Control = &oob[0]
408		msg.SetControllen(len(oob))
409	}
410	msg.Iov = &iov
411	msg.Iovlen = 1
412	if n, err = sendmsg(fd, &msg, flags); err != nil {
413		return 0, err
414	}
415	if len(oob) > 0 && len(p) == 0 {
416		n = 0
417	}
418	return n, nil
419}
420
421//sys	kevent(kq int, change unsafe.Pointer, nchange int, event unsafe.Pointer, nevent int, timeout *Timespec) (n int, err error)
422
423func Kevent(kq int, changes, events []Kevent_t, timeout *Timespec) (n int, err error) {
424	var change, event unsafe.Pointer
425	if len(changes) > 0 {
426		change = unsafe.Pointer(&changes[0])
427	}
428	if len(events) > 0 {
429		event = unsafe.Pointer(&events[0])
430	}
431	return kevent(kq, change, len(changes), event, len(events), timeout)
432}
433
434func Sysctl(name string) (value string, err error) {
435	// Translate name to mib number.
436	mib, err := nametomib(name)
437	if err != nil {
438		return "", err
439	}
440
441	// Find size.
442	n := uintptr(0)
443	if err = sysctl(mib, nil, &n, nil, 0); err != nil {
444		return "", err
445	}
446	if n == 0 {
447		return "", nil
448	}
449
450	// Read into buffer of that size.
451	buf := make([]byte, n)
452	if err = sysctl(mib, &buf[0], &n, nil, 0); err != nil {
453		return "", err
454	}
455
456	// Throw away terminating NUL.
457	if n > 0 && buf[n-1] == '\x00' {
458		n--
459	}
460	return string(buf[0:n]), nil
461}
462
463func SysctlUint32(name string) (value uint32, err error) {
464	// Translate name to mib number.
465	mib, err := nametomib(name)
466	if err != nil {
467		return 0, err
468	}
469
470	// Read into buffer of that size.
471	n := uintptr(4)
472	buf := make([]byte, 4)
473	if err = sysctl(mib, &buf[0], &n, nil, 0); err != nil {
474		return 0, err
475	}
476	if n != 4 {
477		return 0, EIO
478	}
479	return *(*uint32)(unsafe.Pointer(&buf[0])), nil
480}
481
482//sys	utimes(path string, timeval *[2]Timeval) (err error)
483
484func Utimes(path string, tv []Timeval) (err error) {
485	if len(tv) != 2 {
486		return EINVAL
487	}
488	return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
489}
490
491func UtimesNano(path string, ts []Timespec) error {
492	if len(ts) != 2 {
493		return EINVAL
494	}
495	err := utimensat(_AT_FDCWD, path, (*[2]Timespec)(unsafe.Pointer(&ts[0])), 0)
496	if err != ENOSYS {
497		return err
498	}
499	// Not as efficient as it could be because Timespec and
500	// Timeval have different types in the different OSes
501	tv := [2]Timeval{
502		NsecToTimeval(TimespecToNsec(ts[0])),
503		NsecToTimeval(TimespecToNsec(ts[1])),
504	}
505	return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
506}
507
508//sys	futimes(fd int, timeval *[2]Timeval) (err error)
509
510func Futimes(fd int, tv []Timeval) (err error) {
511	if len(tv) != 2 {
512		return EINVAL
513	}
514	return futimes(fd, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
515}
516
517//sys	fcntl(fd int, cmd int, arg int) (val int, err error)
518//sys	fcntlPtr(fd int, cmd int, arg unsafe.Pointer) (val int, err error) = SYS_FCNTL
519//sysnb ioctl(fd int, req int, arg int) (err error)
520//sysnb ioctlPtr(fd int, req uint, arg unsafe.Pointer) (err error) = SYS_IOCTL
521
522var mapper = &mmapper{
523	active: make(map[*byte][]byte),
524	mmap:   mmap,
525	munmap: munmap,
526}
527
528func Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) {
529	return mapper.Mmap(fd, offset, length, prot, flags)
530}
531
532func Munmap(b []byte) (err error) {
533	return mapper.Munmap(b)
534}
535