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.
6 // This file is compiled as ordinary Go code,
7 // but it is also input to mksyscall,
8 // which parses the //sys lines and generates system call stubs.
9 // Note that sometimes we use a lowercase //sys name and
10 // wrap it in our own nicer implementation.
20 // N.B. RawSyscall6 is provided via linkname by runtime/internal/syscall.
22 // Errno is uintptr and thus compatible with the runtime/internal/syscall
25 func RawSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
27 // Pull in entersyscall/exitsyscall for Syscall/Syscall6.
29 // Note that this can't be a push linkname because the runtime already has a
30 // nameless linkname to export to assembly here and in x/sys. Additionally,
31 // entersyscall fetches the caller PC and SP and thus can't have a wrapper
34 //go:linkname runtime_entersyscall runtime.entersyscall
35 func runtime_entersyscall()
37 //go:linkname runtime_exitsyscall runtime.exitsyscall
38 func runtime_exitsyscall()
40 // N.B. For the Syscall functions below:
42 // //go:uintptrkeepalive because the uintptr argument may be converted pointers
43 // that need to be kept alive in the caller (this is implied for RawSyscall6
44 // since it has no body).
46 // //go:nosplit because stack copying does not account for uintptrkeepalive, so
47 // the stack must not grow. Stack copying cannot blindly assume that all
48 // uintptr arguments are pointers, because some values may look like pointers,
49 // but not really be pointers, and adjusting their value would break the call.
51 // //go:norace, on RawSyscall, to avoid race instrumentation if RawSyscall is
52 // called after fork, or from a signal handler.
54 // //go:linkname to ensure ABI wrappers are generated for external callers
55 // (notably x/sys/unix assembly).
60 //go:linkname RawSyscall
61 func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno) {
62 return RawSyscall6(trap, a1, a2, a3, 0, 0, 0)
68 func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno) {
69 runtime_entersyscall()
70 // N.B. Calling RawSyscall here is unsafe with atomic coverage
71 // instrumentation and race mode.
73 // Coverage instrumentation will add a sync/atomic call to RawSyscall.
74 // Race mode will add race instrumentation to sync/atomic. Race
75 // instrumentation requires a P, which we no longer have.
77 // RawSyscall6 is fine because it is implemented in assembly and thus
78 // has no coverage instrumentation.
80 // This is typically not a problem in the runtime because cmd/go avoids
81 // adding coverage instrumentation to the runtime in race mode.
82 r1, r2, err = RawSyscall6(trap, a1, a2, a3, 0, 0, 0)
89 //go:linkname Syscall6
90 func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno) {
91 runtime_entersyscall()
92 r1, r2, err = RawSyscall6(trap, a1, a2, a3, a4, a5, a6)
97 func rawSyscallNoError(trap, a1, a2, a3 uintptr) (r1, r2 uintptr)
98 func rawVforkSyscall(trap, a1, a2, a3 uintptr) (r1 uintptr, err Errno)
104 func Access(path string, mode uint32) (err error) {
105 return Faccessat(_AT_FDCWD, path, mode, 0)
108 func Chmod(path string, mode uint32) (err error) {
109 return Fchmodat(_AT_FDCWD, path, mode, 0)
112 func Chown(path string, uid int, gid int) (err error) {
113 return Fchownat(_AT_FDCWD, path, uid, gid, 0)
116 func Creat(path string, mode uint32) (fd int, err error) {
117 return Open(path, O_CREAT|O_WRONLY|O_TRUNC, mode)
120 func EpollCreate(size int) (fd int, err error) {
124 return EpollCreate1(0)
127 func isGroupMember(gid int) bool {
128 groups, err := Getgroups()
133 for _, g := range groups {
141 func isCapDacOverrideSet() bool {
142 const _CAP_DAC_OVERRIDE = 1
144 c.hdr.version = _LINUX_CAPABILITY_VERSION_3
146 _, _, err := RawSyscall(SYS_CAPGET, uintptr(unsafe.Pointer(&c.hdr)), uintptr(unsafe.Pointer(&c.data[0])), 0)
148 return err == 0 && c.data[0].effective&capToMask(_CAP_DAC_OVERRIDE) != 0
151 //sys faccessat(dirfd int, path string, mode uint32) (err error)
152 //sys faccessat2(dirfd int, path string, mode uint32, flags int) (err error) = _SYS_faccessat2
154 func Faccessat(dirfd int, path string, mode uint32, flags int) (err error) {
156 return faccessat(dirfd, path, mode)
159 // Attempt to use the newer faccessat2, which supports flags directly,
160 // falling back if it doesn't exist.
162 // Don't attempt on Android, which does not allow faccessat2 through
163 // its seccomp policy [1] on any version of Android as of 2022-12-20.
165 // [1] https://cs.android.com/android/platform/superproject/+/master:bionic/libc/SECCOMP_BLOCKLIST_APP.TXT;l=4;drc=dbb8670dfdcc677f7e3b9262e93800fa14c4e417
166 if runtime.GOOS != "android" {
167 if err := faccessat2(dirfd, path, mode, flags); err != ENOSYS && err != EPERM {
172 // The Linux kernel faccessat system call does not take any flags.
173 // The glibc faccessat implements the flags itself; see
174 // https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/unix/sysv/linux/faccessat.c;hb=HEAD
175 // Because people naturally expect syscall.Faccessat to act
176 // like C faccessat, we do the same.
178 if flags & ^(_AT_SYMLINK_NOFOLLOW|_AT_EACCESS) != 0 {
183 if err := fstatat(dirfd, path, &st, flags&_AT_SYMLINK_NOFOLLOW); err != nil {
192 // Fallback to checking permission bits.
194 if flags&_AT_EACCESS != 0 {
196 if uid != 0 && isCapDacOverrideSet() {
197 // If CAP_DAC_OVERRIDE is set, file access check is
198 // done by the kernel in the same way as for root
199 // (see generic_permission() in the Linux sources).
208 // Root can read and write any file.
211 if st.Mode&0111 != 0 {
212 // Root can execute any file that anybody can execute.
219 if uint32(uid) == st.Uid {
220 fmode = (st.Mode >> 6) & 7
223 if flags&_AT_EACCESS != 0 {
229 if uint32(gid) == st.Gid || isGroupMember(int(st.Gid)) {
230 fmode = (st.Mode >> 3) & 7
236 if fmode&mode == mode {
243 //sys fchmodat(dirfd int, path string, mode uint32) (err error)
244 //sys fchmodat2(dirfd int, path string, mode uint32, flags int) (err error) = _SYS_fchmodat2
246 func Fchmodat(dirfd int, path string, mode uint32, flags int) error {
247 // Linux fchmodat doesn't support the flags parameter, but fchmodat2 does.
248 // Try fchmodat2 if flags are specified.
250 err := fchmodat2(dirfd, path, mode, flags)
252 // fchmodat2 isn't available. If the flags are known to be valid,
253 // return EOPNOTSUPP to indicate that fchmodat doesn't support them.
254 if flags&^(_AT_SYMLINK_NOFOLLOW|_AT_EMPTY_PATH) != 0 {
256 } else if flags&(_AT_SYMLINK_NOFOLLOW|_AT_EMPTY_PATH) != 0 {
262 return fchmodat(dirfd, path, mode)
265 //sys linkat(olddirfd int, oldpath string, newdirfd int, newpath string, flags int) (err error)
267 func Link(oldpath string, newpath string) (err error) {
268 return linkat(_AT_FDCWD, oldpath, _AT_FDCWD, newpath, 0)
271 func Mkdir(path string, mode uint32) (err error) {
272 return Mkdirat(_AT_FDCWD, path, mode)
275 func Mknod(path string, mode uint32, dev int) (err error) {
276 return Mknodat(_AT_FDCWD, path, mode, dev)
279 func Open(path string, mode int, perm uint32) (fd int, err error) {
280 return openat(_AT_FDCWD, path, mode|O_LARGEFILE, perm)
283 //sys openat(dirfd int, path string, flags int, mode uint32) (fd int, err error)
285 func Openat(dirfd int, path string, flags int, mode uint32) (fd int, err error) {
286 return openat(dirfd, path, flags|O_LARGEFILE, mode)
289 func Pipe(p []int) error {
293 //sysnb pipe2(p *[2]_C_int, flags int) (err error)
295 func Pipe2(p []int, flags int) error {
300 err := pipe2(&pp, flags)
308 //sys readlinkat(dirfd int, path string, buf []byte) (n int, err error)
310 func Readlink(path string, buf []byte) (n int, err error) {
311 return readlinkat(_AT_FDCWD, path, buf)
314 func Rename(oldpath string, newpath string) (err error) {
315 return Renameat(_AT_FDCWD, oldpath, _AT_FDCWD, newpath)
318 func Rmdir(path string) error {
319 return unlinkat(_AT_FDCWD, path, _AT_REMOVEDIR)
322 //sys symlinkat(oldpath string, newdirfd int, newpath string) (err error)
324 func Symlink(oldpath string, newpath string) (err error) {
325 return symlinkat(oldpath, _AT_FDCWD, newpath)
328 func Unlink(path string) error {
329 return unlinkat(_AT_FDCWD, path, 0)
332 //sys unlinkat(dirfd int, path string, flags int) (err error)
334 func Unlinkat(dirfd int, path string) error {
335 return unlinkat(dirfd, path, 0)
338 func Utimes(path string, tv []Timeval) (err error) {
342 return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
345 //sys utimensat(dirfd int, path string, times *[2]Timespec, flag int) (err error)
347 func UtimesNano(path string, ts []Timespec) (err error) {
351 return utimensat(_AT_FDCWD, path, (*[2]Timespec)(unsafe.Pointer(&ts[0])), 0)
354 func Futimesat(dirfd int, path string, tv []Timeval) (err error) {
358 return futimesat(dirfd, path, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
361 func Futimes(fd int, tv []Timeval) (err error) {
362 // Believe it or not, this is the best we can do on Linux
363 // (and is what glibc does).
364 return Utimes("/proc/self/fd/"+itoa.Itoa(fd), tv)
367 const ImplementsGetwd = true
369 //sys Getcwd(buf []byte) (n int, err error)
371 func Getwd() (wd string, err error) {
372 var buf [PathMax]byte
373 n, err := Getcwd(buf[0:])
377 // Getcwd returns the number of bytes written to buf, including the NUL.
378 if n < 1 || n > len(buf) || buf[n-1] != 0 {
381 // In some cases, Linux can return a path that starts with the
382 // "(unreachable)" prefix, which can potentially be a valid relative
383 // path. To work around that, return ENOENT if path is not absolute.
388 return string(buf[0 : n-1]), nil
391 func Getgroups() (gids []int, err error) {
392 n, err := getgroups(0, nil)
400 // Sanity check group count. Max is 1<<16 on Linux.
401 if n < 0 || n > 1<<20 {
405 a := make([]_Gid_t, n)
406 n, err = getgroups(n, &a[0])
410 gids = make([]int, n)
411 for i, v := range a[0:n] {
417 var cgo_libc_setgroups unsafe.Pointer // non-nil if cgo linked.
419 func Setgroups(gids []int) (err error) {
420 n := uintptr(len(gids))
422 if cgo_libc_setgroups == nil {
423 if _, _, e1 := AllThreadsSyscall(_SYS_setgroups, 0, 0, 0); e1 != 0 {
428 if ret := cgocaller(cgo_libc_setgroups, 0, 0); ret != 0 {
429 err = errnoErr(Errno(ret))
434 a := make([]_Gid_t, len(gids))
435 for i, v := range gids {
438 if cgo_libc_setgroups == nil {
439 if _, _, e1 := AllThreadsSyscall(_SYS_setgroups, n, uintptr(unsafe.Pointer(&a[0])), 0); e1 != 0 {
444 if ret := cgocaller(cgo_libc_setgroups, n, uintptr(unsafe.Pointer(&a[0]))); ret != 0 {
445 err = errnoErr(Errno(ret))
450 type WaitStatus uint32
452 // Wait status is 7 bits at bottom, either 0 (exited),
453 // 0x7F (stopped), or a signal number that caused an exit.
454 // The 0x80 bit is whether there was a core dump.
455 // An extra number (exit code, signal causing a stop)
456 // is in the high bits. At least that's the idea.
457 // There are various irregularities. For example, the
458 // "continued" status is 0xFFFF, distinguishing itself
459 // from stopped via the core dump bit.
469 func (w WaitStatus) Exited() bool { return w&mask == exited }
471 func (w WaitStatus) Signaled() bool { return w&mask != stopped && w&mask != exited }
473 func (w WaitStatus) Stopped() bool { return w&0xFF == stopped }
475 func (w WaitStatus) Continued() bool { return w == 0xFFFF }
477 func (w WaitStatus) CoreDump() bool { return w.Signaled() && w&core != 0 }
479 func (w WaitStatus) ExitStatus() int {
483 return int(w>>shift) & 0xFF
486 func (w WaitStatus) Signal() Signal {
490 return Signal(w & mask)
493 func (w WaitStatus) StopSignal() Signal {
497 return Signal(w>>shift) & 0xFF
500 func (w WaitStatus) TrapCause() int {
501 if w.StopSignal() != SIGTRAP {
504 return int(w>>shift) >> 8
507 //sys wait4(pid int, wstatus *_C_int, options int, rusage *Rusage) (wpid int, err error)
509 func Wait4(pid int, wstatus *WaitStatus, options int, rusage *Rusage) (wpid int, err error) {
511 wpid, err = wait4(pid, &status, options, rusage)
513 *wstatus = WaitStatus(status)
518 func Mkfifo(path string, mode uint32) (err error) {
519 return Mknod(path, mode|S_IFIFO, 0)
522 func (sa *SockaddrInet4) sockaddr() (unsafe.Pointer, _Socklen, error) {
523 if sa.Port < 0 || sa.Port > 0xFFFF {
524 return nil, 0, EINVAL
526 sa.raw.Family = AF_INET
527 p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port))
528 p[0] = byte(sa.Port >> 8)
530 sa.raw.Addr = sa.Addr
531 return unsafe.Pointer(&sa.raw), SizeofSockaddrInet4, nil
534 func (sa *SockaddrInet6) sockaddr() (unsafe.Pointer, _Socklen, error) {
535 if sa.Port < 0 || sa.Port > 0xFFFF {
536 return nil, 0, EINVAL
538 sa.raw.Family = AF_INET6
539 p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port))
540 p[0] = byte(sa.Port >> 8)
542 sa.raw.Scope_id = sa.ZoneId
543 sa.raw.Addr = sa.Addr
544 return unsafe.Pointer(&sa.raw), SizeofSockaddrInet6, nil
547 func (sa *SockaddrUnix) sockaddr() (unsafe.Pointer, _Socklen, error) {
550 if n > len(sa.raw.Path) {
551 return nil, 0, EINVAL
553 if n == len(sa.raw.Path) && name[0] != '@' {
554 return nil, 0, EINVAL
556 sa.raw.Family = AF_UNIX
557 for i := 0; i < n; i++ {
558 sa.raw.Path[i] = int8(name[i])
560 // length is family (uint16), name, NUL.
563 sl += _Socklen(n) + 1
565 if sa.raw.Path[0] == '@' || (sa.raw.Path[0] == 0 && sl > 3) {
566 // Check sl > 3 so we don't change unnamed socket behavior.
568 // Don't count trailing NUL for abstract address.
572 return unsafe.Pointer(&sa.raw), sl, nil
575 type SockaddrLinklayer struct {
582 raw RawSockaddrLinklayer
585 func (sa *SockaddrLinklayer) sockaddr() (unsafe.Pointer, _Socklen, error) {
586 if sa.Ifindex < 0 || sa.Ifindex > 0x7fffffff {
587 return nil, 0, EINVAL
589 sa.raw.Family = AF_PACKET
590 sa.raw.Protocol = sa.Protocol
591 sa.raw.Ifindex = int32(sa.Ifindex)
592 sa.raw.Hatype = sa.Hatype
593 sa.raw.Pkttype = sa.Pkttype
594 sa.raw.Halen = sa.Halen
595 sa.raw.Addr = sa.Addr
596 return unsafe.Pointer(&sa.raw), SizeofSockaddrLinklayer, nil
599 type SockaddrNetlink struct {
604 raw RawSockaddrNetlink
607 func (sa *SockaddrNetlink) sockaddr() (unsafe.Pointer, _Socklen, error) {
608 sa.raw.Family = AF_NETLINK
611 sa.raw.Groups = sa.Groups
612 return unsafe.Pointer(&sa.raw), SizeofSockaddrNetlink, nil
615 func anyToSockaddr(rsa *RawSockaddrAny) (Sockaddr, error) {
616 switch rsa.Addr.Family {
618 pp := (*RawSockaddrNetlink)(unsafe.Pointer(rsa))
619 sa := new(SockaddrNetlink)
620 sa.Family = pp.Family
623 sa.Groups = pp.Groups
627 pp := (*RawSockaddrLinklayer)(unsafe.Pointer(rsa))
628 sa := new(SockaddrLinklayer)
629 sa.Protocol = pp.Protocol
630 sa.Ifindex = int(pp.Ifindex)
631 sa.Hatype = pp.Hatype
632 sa.Pkttype = pp.Pkttype
638 pp := (*RawSockaddrUnix)(unsafe.Pointer(rsa))
639 sa := new(SockaddrUnix)
641 // "Abstract" Unix domain socket.
642 // Rewrite leading NUL as @ for textual display.
643 // (This is the standard convention.)
644 // Not friendly to overwrite in place,
645 // but the callers below don't care.
649 // Assume path ends at NUL.
650 // This is not technically the Linux semantics for
651 // abstract Unix domain sockets--they are supposed
652 // to be uninterpreted fixed-size binary blobs--but
653 // everyone uses this convention.
655 for n < len(pp.Path) && pp.Path[n] != 0 {
658 sa.Name = string(unsafe.Slice((*byte)(unsafe.Pointer(&pp.Path[0])), n))
662 pp := (*RawSockaddrInet4)(unsafe.Pointer(rsa))
663 sa := new(SockaddrInet4)
664 p := (*[2]byte)(unsafe.Pointer(&pp.Port))
665 sa.Port = int(p[0])<<8 + int(p[1])
670 pp := (*RawSockaddrInet6)(unsafe.Pointer(rsa))
671 sa := new(SockaddrInet6)
672 p := (*[2]byte)(unsafe.Pointer(&pp.Port))
673 sa.Port = int(p[0])<<8 + int(p[1])
674 sa.ZoneId = pp.Scope_id
678 return nil, EAFNOSUPPORT
681 func Accept4(fd int, flags int) (nfd int, sa Sockaddr, err error) {
682 var rsa RawSockaddrAny
683 var len _Socklen = SizeofSockaddrAny
684 nfd, err = accept4(fd, &rsa, &len, flags)
688 if len > SizeofSockaddrAny {
689 panic("RawSockaddrAny too small")
691 sa, err = anyToSockaddr(&rsa)
699 func Getsockname(fd int) (sa Sockaddr, err error) {
700 var rsa RawSockaddrAny
701 var len _Socklen = SizeofSockaddrAny
702 if err = getsockname(fd, &rsa, &len); err != nil {
705 return anyToSockaddr(&rsa)
708 func GetsockoptInet4Addr(fd, level, opt int) (value [4]byte, err error) {
709 vallen := _Socklen(4)
710 err = getsockopt(fd, level, opt, unsafe.Pointer(&value[0]), &vallen)
714 func GetsockoptIPMreq(fd, level, opt int) (*IPMreq, error) {
716 vallen := _Socklen(SizeofIPMreq)
717 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
721 func GetsockoptIPMreqn(fd, level, opt int) (*IPMreqn, error) {
723 vallen := _Socklen(SizeofIPMreqn)
724 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
728 func GetsockoptIPv6Mreq(fd, level, opt int) (*IPv6Mreq, error) {
730 vallen := _Socklen(SizeofIPv6Mreq)
731 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
735 func GetsockoptIPv6MTUInfo(fd, level, opt int) (*IPv6MTUInfo, error) {
736 var value IPv6MTUInfo
737 vallen := _Socklen(SizeofIPv6MTUInfo)
738 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
742 func GetsockoptICMPv6Filter(fd, level, opt int) (*ICMPv6Filter, error) {
743 var value ICMPv6Filter
744 vallen := _Socklen(SizeofICMPv6Filter)
745 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
749 func GetsockoptUcred(fd, level, opt int) (*Ucred, error) {
751 vallen := _Socklen(SizeofUcred)
752 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
756 func SetsockoptIPMreqn(fd, level, opt int, mreq *IPMreqn) (err error) {
757 return setsockopt(fd, level, opt, unsafe.Pointer(mreq), unsafe.Sizeof(*mreq))
760 func recvmsgRaw(fd int, p, oob []byte, flags int, rsa *RawSockaddrAny) (n, oobn int, recvflags int, err error) {
762 msg.Name = (*byte)(unsafe.Pointer(rsa))
763 msg.Namelen = uint32(SizeofSockaddrAny)
773 sockType, err = GetsockoptInt(fd, SOL_SOCKET, SO_TYPE)
777 // receive at least one normal byte
778 if sockType != SOCK_DGRAM {
783 msg.Control = &oob[0]
784 msg.SetControllen(len(oob))
788 if n, err = recvmsg(fd, &msg, flags); err != nil {
791 oobn = int(msg.Controllen)
792 recvflags = int(msg.Flags)
796 func sendmsgN(fd int, p, oob []byte, ptr unsafe.Pointer, salen _Socklen, flags int) (n int, err error) {
798 msg.Name = (*byte)(ptr)
799 msg.Namelen = uint32(salen)
809 sockType, err = GetsockoptInt(fd, SOL_SOCKET, SO_TYPE)
813 // send at least one normal byte
814 if sockType != SOCK_DGRAM {
819 msg.Control = &oob[0]
820 msg.SetControllen(len(oob))
824 if n, err = sendmsg(fd, &msg, flags); err != nil {
827 if len(oob) > 0 && len(p) == 0 {
833 // BindToDevice binds the socket associated with fd to device.
834 func BindToDevice(fd int, device string) (err error) {
835 return SetsockoptString(fd, SOL_SOCKET, SO_BINDTODEVICE, device)
838 //sys ptrace(request int, pid int, addr uintptr, data uintptr) (err error)
839 //sys ptracePtr(request int, pid int, addr uintptr, data unsafe.Pointer) (err error) = SYS_PTRACE
841 func ptracePeek(req int, pid int, addr uintptr, out []byte) (count int, err error) {
842 // The peek requests are machine-size oriented, so we wrap it
843 // to retrieve arbitrary-length data.
845 // The ptrace syscall differs from glibc's ptrace.
846 // Peeks returns the word in *data, not as the return value.
848 var buf [sizeofPtr]byte
850 // Leading edge. PEEKTEXT/PEEKDATA don't require aligned
851 // access (PEEKUSER warns that it might), but if we don't
852 // align our reads, we might straddle an unmapped page
853 // boundary and not get the bytes leading up to the page
856 if addr%sizeofPtr != 0 {
857 err = ptracePtr(req, pid, addr-addr%sizeofPtr, unsafe.Pointer(&buf[0]))
861 n += copy(out, buf[addr%sizeofPtr:])
867 // We use an internal buffer to guarantee alignment.
868 // It's not documented if this is necessary, but we're paranoid.
869 err = ptracePtr(req, pid, addr+uintptr(n), unsafe.Pointer(&buf[0]))
873 copied := copy(out, buf[0:])
881 func PtracePeekText(pid int, addr uintptr, out []byte) (count int, err error) {
882 return ptracePeek(PTRACE_PEEKTEXT, pid, addr, out)
885 func PtracePeekData(pid int, addr uintptr, out []byte) (count int, err error) {
886 return ptracePeek(PTRACE_PEEKDATA, pid, addr, out)
889 func ptracePoke(pokeReq int, peekReq int, pid int, addr uintptr, data []byte) (count int, err error) {
890 // As for ptracePeek, we need to align our accesses to deal
891 // with the possibility of straddling an invalid page.
895 if addr%sizeofPtr != 0 {
896 var buf [sizeofPtr]byte
897 err = ptracePtr(peekReq, pid, addr-addr%sizeofPtr, unsafe.Pointer(&buf[0]))
901 n += copy(buf[addr%sizeofPtr:], data)
902 word := *((*uintptr)(unsafe.Pointer(&buf[0])))
903 err = ptrace(pokeReq, pid, addr-addr%sizeofPtr, word)
911 for len(data) > sizeofPtr {
912 word := *((*uintptr)(unsafe.Pointer(&data[0])))
913 err = ptrace(pokeReq, pid, addr+uintptr(n), word)
918 data = data[sizeofPtr:]
923 var buf [sizeofPtr]byte
924 err = ptracePtr(peekReq, pid, addr+uintptr(n), unsafe.Pointer(&buf[0]))
929 word := *((*uintptr)(unsafe.Pointer(&buf[0])))
930 err = ptrace(pokeReq, pid, addr+uintptr(n), word)
940 func PtracePokeText(pid int, addr uintptr, data []byte) (count int, err error) {
941 return ptracePoke(PTRACE_POKETEXT, PTRACE_PEEKTEXT, pid, addr, data)
944 func PtracePokeData(pid int, addr uintptr, data []byte) (count int, err error) {
945 return ptracePoke(PTRACE_POKEDATA, PTRACE_PEEKDATA, pid, addr, data)
952 func PtraceGetRegs(pid int, regsout *PtraceRegs) (err error) {
954 iov.Base = (*byte)(unsafe.Pointer(regsout))
955 iov.SetLen(int(unsafe.Sizeof(*regsout)))
956 return ptracePtr(PTRACE_GETREGSET, pid, uintptr(_NT_PRSTATUS), unsafe.Pointer(&iov))
959 func PtraceSetRegs(pid int, regs *PtraceRegs) (err error) {
961 iov.Base = (*byte)(unsafe.Pointer(regs))
962 iov.SetLen(int(unsafe.Sizeof(*regs)))
963 return ptracePtr(PTRACE_SETREGSET, pid, uintptr(_NT_PRSTATUS), unsafe.Pointer(&iov))
966 func PtraceSetOptions(pid int, options int) (err error) {
967 return ptrace(PTRACE_SETOPTIONS, pid, 0, uintptr(options))
970 func PtraceGetEventMsg(pid int) (msg uint, err error) {
972 err = ptracePtr(PTRACE_GETEVENTMSG, pid, 0, unsafe.Pointer(&data))
977 func PtraceCont(pid int, signal int) (err error) {
978 return ptrace(PTRACE_CONT, pid, 0, uintptr(signal))
981 func PtraceSyscall(pid int, signal int) (err error) {
982 return ptrace(PTRACE_SYSCALL, pid, 0, uintptr(signal))
985 func PtraceSingleStep(pid int) (err error) { return ptrace(PTRACE_SINGLESTEP, pid, 0, 0) }
987 func PtraceAttach(pid int) (err error) { return ptrace(PTRACE_ATTACH, pid, 0, 0) }
989 func PtraceDetach(pid int) (err error) { return ptrace(PTRACE_DETACH, pid, 0, 0) }
991 //sys reboot(magic1 uint, magic2 uint, cmd int, arg string) (err error)
993 func Reboot(cmd int) (err error) {
994 return reboot(LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, cmd, "")
997 func ReadDirent(fd int, buf []byte) (n int, err error) {
998 return Getdents(fd, buf)
1001 func direntIno(buf []byte) (uint64, bool) {
1002 return readInt(buf, unsafe.Offsetof(Dirent{}.Ino), unsafe.Sizeof(Dirent{}.Ino))
1005 func direntReclen(buf []byte) (uint64, bool) {
1006 return readInt(buf, unsafe.Offsetof(Dirent{}.Reclen), unsafe.Sizeof(Dirent{}.Reclen))
1009 func direntNamlen(buf []byte) (uint64, bool) {
1010 reclen, ok := direntReclen(buf)
1014 return reclen - uint64(unsafe.Offsetof(Dirent{}.Name)), true
1017 //sys mount(source string, target string, fstype string, flags uintptr, data *byte) (err error)
1019 func Mount(source string, target string, fstype string, flags uintptr, data string) (err error) {
1020 // Certain file systems get rather angry and EINVAL if you give
1021 // them an empty string of data, rather than NULL.
1023 return mount(source, target, fstype, flags, nil)
1025 datap, err := BytePtrFromString(data)
1029 return mount(source, target, fstype, flags, datap)
1039 //sys Acct(path string) (err error)
1040 //sys Adjtimex(buf *Timex) (state int, err error)
1041 //sys Chdir(path string) (err error)
1042 //sys Chroot(path string) (err error)
1043 //sys Close(fd int) (err error)
1044 //sys Dup(oldfd int) (fd int, err error)
1045 //sys Dup3(oldfd int, newfd int, flags int) (err error)
1046 //sysnb EpollCreate1(flag int) (fd int, err error)
1047 //sysnb EpollCtl(epfd int, op int, fd int, event *EpollEvent) (err error)
1048 //sys Fallocate(fd int, mode uint32, off int64, len int64) (err error)
1049 //sys Fchdir(fd int) (err error)
1050 //sys Fchmod(fd int, mode uint32) (err error)
1051 //sys Fchownat(dirfd int, path string, uid int, gid int, flags int) (err error)
1052 //sys fcntl(fd int, cmd int, arg int) (val int, err error)
1053 //sys Fdatasync(fd int) (err error)
1054 //sys Flock(fd int, how int) (err error)
1055 //sys Fsync(fd int) (err error)
1056 //sys Getdents(fd int, buf []byte) (n int, err error) = SYS_GETDENTS64
1057 //sysnb Getpgid(pid int) (pgid int, err error)
1059 func Getpgrp() (pid int) {
1064 //sysnb Getpid() (pid int)
1065 //sysnb Getppid() (ppid int)
1066 //sys Getpriority(which int, who int) (prio int, err error)
1067 //sysnb Getrusage(who int, rusage *Rusage) (err error)
1068 //sysnb Gettid() (tid int)
1069 //sys Getxattr(path string, attr string, dest []byte) (sz int, err error)
1070 //sys InotifyAddWatch(fd int, pathname string, mask uint32) (watchdesc int, err error)
1071 //sysnb InotifyInit1(flags int) (fd int, err error)
1072 //sysnb InotifyRmWatch(fd int, watchdesc uint32) (success int, err error)
1073 //sysnb Kill(pid int, sig Signal) (err error)
1074 //sys Klogctl(typ int, buf []byte) (n int, err error) = SYS_SYSLOG
1075 //sys Listxattr(path string, dest []byte) (sz int, err error)
1076 //sys Mkdirat(dirfd int, path string, mode uint32) (err error)
1077 //sys Mknodat(dirfd int, path string, mode uint32, dev int) (err error)
1078 //sys Nanosleep(time *Timespec, leftover *Timespec) (err error)
1079 //sys PivotRoot(newroot string, putold string) (err error) = SYS_PIVOT_ROOT
1080 //sysnb prlimit1(pid int, resource int, newlimit *Rlimit, old *Rlimit) (err error) = SYS_PRLIMIT64
1081 //sys read(fd int, p []byte) (n int, err error)
1082 //sys Removexattr(path string, attr string) (err error)
1083 //sys Setdomainname(p []byte) (err error)
1084 //sys Sethostname(p []byte) (err error)
1085 //sysnb Setpgid(pid int, pgid int) (err error)
1086 //sysnb Setsid() (pid int, err error)
1087 //sysnb Settimeofday(tv *Timeval) (err error)
1089 // Provided by runtime.syscall_runtime_doAllThreadsSyscall which stops the
1090 // world and invokes the syscall on each OS thread. Once this function returns,
1091 // all threads are in sync.
1094 func runtime_doAllThreadsSyscall(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr)
1096 // AllThreadsSyscall performs a syscall on each OS thread of the Go
1097 // runtime. It first invokes the syscall on one thread. Should that
1098 // invocation fail, it returns immediately with the error status.
1099 // Otherwise, it invokes the syscall on all of the remaining threads
1100 // in parallel. It will terminate the program if it observes any
1101 // invoked syscall's return value differs from that of the first
1104 // AllThreadsSyscall is intended for emulating simultaneous
1105 // process-wide state changes that require consistently modifying
1106 // per-thread state of the Go runtime.
1108 // AllThreadsSyscall is unaware of any threads that are launched
1109 // explicitly by cgo linked code, so the function always returns
1110 // ENOTSUP in binaries that use cgo.
1113 func AllThreadsSyscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno) {
1114 if cgo_libc_setegid != nil {
1115 return minus1, minus1, ENOTSUP
1117 r1, r2, errno := runtime_doAllThreadsSyscall(trap, a1, a2, a3, 0, 0, 0)
1118 return r1, r2, Errno(errno)
1121 // AllThreadsSyscall6 is like AllThreadsSyscall, but extended to six
1125 func AllThreadsSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno) {
1126 if cgo_libc_setegid != nil {
1127 return minus1, minus1, ENOTSUP
1129 r1, r2, errno := runtime_doAllThreadsSyscall(trap, a1, a2, a3, a4, a5, a6)
1130 return r1, r2, Errno(errno)
1133 // linked by runtime.cgocall.go
1136 func cgocaller(unsafe.Pointer, ...uintptr) uintptr
1138 var cgo_libc_setegid unsafe.Pointer // non-nil if cgo linked.
1140 const minus1 = ^uintptr(0)
1142 func Setegid(egid int) (err error) {
1143 if cgo_libc_setegid == nil {
1144 if _, _, e1 := AllThreadsSyscall(SYS_SETRESGID, minus1, uintptr(egid), minus1); e1 != 0 {
1147 } else if ret := cgocaller(cgo_libc_setegid, uintptr(egid)); ret != 0 {
1148 err = errnoErr(Errno(ret))
1153 var cgo_libc_seteuid unsafe.Pointer // non-nil if cgo linked.
1155 func Seteuid(euid int) (err error) {
1156 if cgo_libc_seteuid == nil {
1157 if _, _, e1 := AllThreadsSyscall(SYS_SETRESUID, minus1, uintptr(euid), minus1); e1 != 0 {
1160 } else if ret := cgocaller(cgo_libc_seteuid, uintptr(euid)); ret != 0 {
1161 err = errnoErr(Errno(ret))
1166 var cgo_libc_setgid unsafe.Pointer // non-nil if cgo linked.
1168 func Setgid(gid int) (err error) {
1169 if cgo_libc_setgid == nil {
1170 if _, _, e1 := AllThreadsSyscall(sys_SETGID, uintptr(gid), 0, 0); e1 != 0 {
1173 } else if ret := cgocaller(cgo_libc_setgid, uintptr(gid)); ret != 0 {
1174 err = errnoErr(Errno(ret))
1179 var cgo_libc_setregid unsafe.Pointer // non-nil if cgo linked.
1181 func Setregid(rgid, egid int) (err error) {
1182 if cgo_libc_setregid == nil {
1183 if _, _, e1 := AllThreadsSyscall(sys_SETREGID, uintptr(rgid), uintptr(egid), 0); e1 != 0 {
1186 } else if ret := cgocaller(cgo_libc_setregid, uintptr(rgid), uintptr(egid)); ret != 0 {
1187 err = errnoErr(Errno(ret))
1192 var cgo_libc_setresgid unsafe.Pointer // non-nil if cgo linked.
1194 func Setresgid(rgid, egid, sgid int) (err error) {
1195 if cgo_libc_setresgid == nil {
1196 if _, _, e1 := AllThreadsSyscall(sys_SETRESGID, uintptr(rgid), uintptr(egid), uintptr(sgid)); e1 != 0 {
1199 } else if ret := cgocaller(cgo_libc_setresgid, uintptr(rgid), uintptr(egid), uintptr(sgid)); ret != 0 {
1200 err = errnoErr(Errno(ret))
1205 var cgo_libc_setresuid unsafe.Pointer // non-nil if cgo linked.
1207 func Setresuid(ruid, euid, suid int) (err error) {
1208 if cgo_libc_setresuid == nil {
1209 if _, _, e1 := AllThreadsSyscall(sys_SETRESUID, uintptr(ruid), uintptr(euid), uintptr(suid)); e1 != 0 {
1212 } else if ret := cgocaller(cgo_libc_setresuid, uintptr(ruid), uintptr(euid), uintptr(suid)); ret != 0 {
1213 err = errnoErr(Errno(ret))
1218 var cgo_libc_setreuid unsafe.Pointer // non-nil if cgo linked.
1220 func Setreuid(ruid, euid int) (err error) {
1221 if cgo_libc_setreuid == nil {
1222 if _, _, e1 := AllThreadsSyscall(sys_SETREUID, uintptr(ruid), uintptr(euid), 0); e1 != 0 {
1225 } else if ret := cgocaller(cgo_libc_setreuid, uintptr(ruid), uintptr(euid)); ret != 0 {
1226 err = errnoErr(Errno(ret))
1231 var cgo_libc_setuid unsafe.Pointer // non-nil if cgo linked.
1233 func Setuid(uid int) (err error) {
1234 if cgo_libc_setuid == nil {
1235 if _, _, e1 := AllThreadsSyscall(sys_SETUID, uintptr(uid), 0, 0); e1 != 0 {
1238 } else if ret := cgocaller(cgo_libc_setuid, uintptr(uid)); ret != 0 {
1239 err = errnoErr(Errno(ret))
1244 //sys Setpriority(which int, who int, prio int) (err error)
1245 //sys Setxattr(path string, attr string, data []byte, flags int) (err error)
1247 //sysnb Sysinfo(info *Sysinfo_t) (err error)
1248 //sys Tee(rfd int, wfd int, len int, flags int) (n int64, err error)
1249 //sysnb Tgkill(tgid int, tid int, sig Signal) (err error)
1250 //sysnb Times(tms *Tms) (ticks uintptr, err error)
1251 //sysnb Umask(mask int) (oldmask int)
1252 //sysnb Uname(buf *Utsname) (err error)
1253 //sys Unmount(target string, flags int) (err error) = SYS_UMOUNT2
1254 //sys Unshare(flags int) (err error)
1255 //sys write(fd int, p []byte) (n int, err error)
1256 //sys exitThread(code int) (err error) = SYS_EXIT
1257 //sys readlen(fd int, p *byte, np int) (n int, err error) = SYS_READ
1259 // mmap varies by architecture; see syscall_linux_*.go.
1260 //sys munmap(addr uintptr, length uintptr) (err error)
1262 var mapper = &mmapper{
1263 active: make(map[*byte][]byte),
1268 func Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) {
1269 return mapper.Mmap(fd, offset, length, prot, flags)
1272 func Munmap(b []byte) (err error) {
1273 return mapper.Munmap(b)
1276 //sys Madvise(b []byte, advice int) (err error)
1277 //sys Mprotect(b []byte, prot int) (err error)
1278 //sys Mlock(b []byte) (err error)
1279 //sys Munlock(b []byte) (err error)
1280 //sys Mlockall(flags int) (err error)
1281 //sys Munlockall() (err error)
1283 // prlimit changes a resource limit. We use a single definition so that
1284 // we can tell StartProcess to not restore the original NOFILE limit.
1285 // This is unexported but can be called from x/sys/unix.
1286 func prlimit(pid int, resource int, newlimit *Rlimit, old *Rlimit) (err error) {
1287 err = prlimit1(pid, resource, newlimit, old)
1288 if err == nil && newlimit != nil && resource == RLIMIT_NOFILE {
1289 origRlimitNofile.Store(nil)