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// +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 unix 14 15import ( 16 "runtime" 17 "syscall" 18 "unsafe" 19) 20 21/* 22 * Wrapped 23 */ 24 25//sysnb getgroups(ngid int, gid *_Gid_t) (n int, err error) 26//sysnb setgroups(ngid int, gid *_Gid_t) (err error) 27 28func Getgroups() (gids []int, err error) { 29 n, err := getgroups(0, nil) 30 if err != nil { 31 return nil, err 32 } 33 if n == 0 { 34 return nil, nil 35 } 36 37 // Sanity check group count. Max is 16 on BSD. 38 if n < 0 || n > 1000 { 39 return nil, EINVAL 40 } 41 42 a := make([]_Gid_t, n) 43 n, err = getgroups(n, &a[0]) 44 if err != nil { 45 return nil, err 46 } 47 gids = make([]int, n) 48 for i, v := range a[0:n] { 49 gids[i] = int(v) 50 } 51 return 52} 53 54func Setgroups(gids []int) (err error) { 55 if len(gids) == 0 { 56 return setgroups(0, nil) 57 } 58 59 a := make([]_Gid_t, len(gids)) 60 for i, v := range gids { 61 a[i] = _Gid_t(v) 62 } 63 return setgroups(len(a), &a[0]) 64} 65 66func ReadDirent(fd int, buf []byte) (n int, err error) { 67 // Final argument is (basep *uintptr) and the syscall doesn't take nil. 68 // 64 bits should be enough. (32 bits isn't even on 386). Since the 69 // actual system call is getdirentries64, 64 is a good guess. 70 // TODO(rsc): Can we use a single global basep for all calls? 71 var base = (*uintptr)(unsafe.Pointer(new(uint64))) 72 return Getdirentries(fd, buf, base) 73} 74 75// Wait status is 7 bits at bottom, either 0 (exited), 76// 0x7F (stopped), or a signal number that caused an exit. 77// The 0x80 bit is whether there was a core dump. 78// An extra number (exit code, signal causing a stop) 79// is in the high bits. 80 81type WaitStatus uint32 82 83const ( 84 mask = 0x7F 85 core = 0x80 86 shift = 8 87 88 exited = 0 89 stopped = 0x7F 90) 91 92func (w WaitStatus) Exited() bool { return w&mask == exited } 93 94func (w WaitStatus) ExitStatus() int { 95 if w&mask != exited { 96 return -1 97 } 98 return int(w >> shift) 99} 100 101func (w WaitStatus) Signaled() bool { return w&mask != stopped && w&mask != 0 } 102 103func (w WaitStatus) Signal() syscall.Signal { 104 sig := syscall.Signal(w & mask) 105 if sig == stopped || sig == 0 { 106 return -1 107 } 108 return sig 109} 110 111func (w WaitStatus) CoreDump() bool { return w.Signaled() && w&core != 0 } 112 113func (w WaitStatus) Stopped() bool { return w&mask == stopped && syscall.Signal(w>>shift) != SIGSTOP } 114 115func (w WaitStatus) Continued() bool { return w&mask == stopped && syscall.Signal(w>>shift) == SIGSTOP } 116 117func (w WaitStatus) StopSignal() syscall.Signal { 118 if !w.Stopped() { 119 return -1 120 } 121 return syscall.Signal(w>>shift) & 0xFF 122} 123 124func (w WaitStatus) TrapCause() int { return -1 } 125 126//sys wait4(pid int, wstatus *_C_int, options int, rusage *Rusage) (wpid int, err error) 127 128func Wait4(pid int, wstatus *WaitStatus, options int, rusage *Rusage) (wpid int, err error) { 129 var status _C_int 130 wpid, err = wait4(pid, &status, options, rusage) 131 if wstatus != nil { 132 *wstatus = WaitStatus(status) 133 } 134 return 135} 136 137//sys accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, err error) 138//sys bind(s int, addr unsafe.Pointer, addrlen _Socklen) (err error) 139//sys connect(s int, addr unsafe.Pointer, addrlen _Socklen) (err error) 140//sysnb socket(domain int, typ int, proto int) (fd int, err error) 141//sys getsockopt(s int, level int, name int, val unsafe.Pointer, vallen *_Socklen) (err error) 142//sys setsockopt(s int, level int, name int, val unsafe.Pointer, vallen uintptr) (err error) 143//sysnb getpeername(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error) 144//sysnb getsockname(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error) 145//sys Shutdown(s int, how int) (err error) 146 147func (sa *SockaddrInet4) sockaddr() (unsafe.Pointer, _Socklen, error) { 148 if sa.Port < 0 || sa.Port > 0xFFFF { 149 return nil, 0, EINVAL 150 } 151 sa.raw.Len = SizeofSockaddrInet4 152 sa.raw.Family = AF_INET 153 p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port)) 154 p[0] = byte(sa.Port >> 8) 155 p[1] = byte(sa.Port) 156 for i := 0; i < len(sa.Addr); i++ { 157 sa.raw.Addr[i] = sa.Addr[i] 158 } 159 return unsafe.Pointer(&sa.raw), _Socklen(sa.raw.Len), nil 160} 161 162func (sa *SockaddrInet6) sockaddr() (unsafe.Pointer, _Socklen, error) { 163 if sa.Port < 0 || sa.Port > 0xFFFF { 164 return nil, 0, EINVAL 165 } 166 sa.raw.Len = SizeofSockaddrInet6 167 sa.raw.Family = AF_INET6 168 p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port)) 169 p[0] = byte(sa.Port >> 8) 170 p[1] = byte(sa.Port) 171 sa.raw.Scope_id = sa.ZoneId 172 for i := 0; i < len(sa.Addr); i++ { 173 sa.raw.Addr[i] = sa.Addr[i] 174 } 175 return unsafe.Pointer(&sa.raw), _Socklen(sa.raw.Len), nil 176} 177 178func (sa *SockaddrUnix) sockaddr() (unsafe.Pointer, _Socklen, error) { 179 name := sa.Name 180 n := len(name) 181 if n >= len(sa.raw.Path) || n == 0 { 182 return nil, 0, EINVAL 183 } 184 sa.raw.Len = byte(3 + n) // 2 for Family, Len; 1 for NUL 185 sa.raw.Family = AF_UNIX 186 for i := 0; i < n; i++ { 187 sa.raw.Path[i] = int8(name[i]) 188 } 189 return unsafe.Pointer(&sa.raw), _Socklen(sa.raw.Len), nil 190} 191 192func (sa *SockaddrDatalink) sockaddr() (unsafe.Pointer, _Socklen, error) { 193 if sa.Index == 0 { 194 return nil, 0, EINVAL 195 } 196 sa.raw.Len = sa.Len 197 sa.raw.Family = AF_LINK 198 sa.raw.Index = sa.Index 199 sa.raw.Type = sa.Type 200 sa.raw.Nlen = sa.Nlen 201 sa.raw.Alen = sa.Alen 202 sa.raw.Slen = sa.Slen 203 for i := 0; i < len(sa.raw.Data); i++ { 204 sa.raw.Data[i] = sa.Data[i] 205 } 206 return unsafe.Pointer(&sa.raw), SizeofSockaddrDatalink, nil 207} 208 209func anyToSockaddr(fd int, rsa *RawSockaddrAny) (Sockaddr, error) { 210 switch rsa.Addr.Family { 211 case AF_LINK: 212 pp := (*RawSockaddrDatalink)(unsafe.Pointer(rsa)) 213 sa := new(SockaddrDatalink) 214 sa.Len = pp.Len 215 sa.Family = pp.Family 216 sa.Index = pp.Index 217 sa.Type = pp.Type 218 sa.Nlen = pp.Nlen 219 sa.Alen = pp.Alen 220 sa.Slen = pp.Slen 221 for i := 0; i < len(sa.Data); i++ { 222 sa.Data[i] = pp.Data[i] 223 } 224 return sa, nil 225 226 case AF_UNIX: 227 pp := (*RawSockaddrUnix)(unsafe.Pointer(rsa)) 228 if pp.Len < 2 || pp.Len > SizeofSockaddrUnix { 229 return nil, EINVAL 230 } 231 sa := new(SockaddrUnix) 232 233 // Some BSDs include the trailing NUL in the length, whereas 234 // others do not. Work around this by subtracting the leading 235 // family and len. The path is then scanned to see if a NUL 236 // terminator still exists within the length. 237 n := int(pp.Len) - 2 // subtract leading Family, Len 238 for i := 0; i < n; i++ { 239 if pp.Path[i] == 0 { 240 // found early NUL; assume Len included the NUL 241 // or was overestimating. 242 n = i 243 break 244 } 245 } 246 bytes := (*[10000]byte)(unsafe.Pointer(&pp.Path[0]))[0:n] 247 sa.Name = string(bytes) 248 return sa, nil 249 250 case AF_INET: 251 pp := (*RawSockaddrInet4)(unsafe.Pointer(rsa)) 252 sa := new(SockaddrInet4) 253 p := (*[2]byte)(unsafe.Pointer(&pp.Port)) 254 sa.Port = int(p[0])<<8 + int(p[1]) 255 for i := 0; i < len(sa.Addr); i++ { 256 sa.Addr[i] = pp.Addr[i] 257 } 258 return sa, nil 259 260 case AF_INET6: 261 pp := (*RawSockaddrInet6)(unsafe.Pointer(rsa)) 262 sa := new(SockaddrInet6) 263 p := (*[2]byte)(unsafe.Pointer(&pp.Port)) 264 sa.Port = int(p[0])<<8 + int(p[1]) 265 sa.ZoneId = pp.Scope_id 266 for i := 0; i < len(sa.Addr); i++ { 267 sa.Addr[i] = pp.Addr[i] 268 } 269 return sa, nil 270 } 271 return nil, EAFNOSUPPORT 272} 273 274func Accept(fd int) (nfd int, sa Sockaddr, err error) { 275 var rsa RawSockaddrAny 276 var len _Socklen = SizeofSockaddrAny 277 nfd, err = accept(fd, &rsa, &len) 278 if err != nil { 279 return 280 } 281 if runtime.GOOS == "darwin" && len == 0 { 282 // Accepted socket has no address. 283 // This is likely due to a bug in xnu kernels, 284 // where instead of ECONNABORTED error socket 285 // is accepted, but has no address. 286 Close(nfd) 287 return 0, nil, ECONNABORTED 288 } 289 sa, err = anyToSockaddr(fd, &rsa) 290 if err != nil { 291 Close(nfd) 292 nfd = 0 293 } 294 return 295} 296 297func Getsockname(fd int) (sa Sockaddr, err error) { 298 var rsa RawSockaddrAny 299 var len _Socklen = SizeofSockaddrAny 300 if err = getsockname(fd, &rsa, &len); err != nil { 301 return 302 } 303 // TODO(jsing): DragonFly has a "bug" (see issue 3349), which should be 304 // reported upstream. 305 if runtime.GOOS == "dragonfly" && rsa.Addr.Family == AF_UNSPEC && rsa.Addr.Len == 0 { 306 rsa.Addr.Family = AF_UNIX 307 rsa.Addr.Len = SizeofSockaddrUnix 308 } 309 return anyToSockaddr(fd, &rsa) 310} 311 312//sysnb socketpair(domain int, typ int, proto int, fd *[2]int32) (err error) 313 314// GetsockoptString returns the string value of the socket option opt for the 315// socket associated with fd at the given socket level. 316func GetsockoptString(fd, level, opt int) (string, error) { 317 buf := make([]byte, 256) 318 vallen := _Socklen(len(buf)) 319 err := getsockopt(fd, level, opt, unsafe.Pointer(&buf[0]), &vallen) 320 if err != nil { 321 return "", err 322 } 323 return string(buf[:vallen-1]), nil 324} 325 326//sys recvfrom(fd int, p []byte, flags int, from *RawSockaddrAny, fromlen *_Socklen) (n int, err error) 327//sys sendto(s int, buf []byte, flags int, to unsafe.Pointer, addrlen _Socklen) (err error) 328//sys recvmsg(s int, msg *Msghdr, flags int) (n int, err error) 329 330func Recvmsg(fd int, p, oob []byte, flags int) (n, oobn int, recvflags int, from Sockaddr, err error) { 331 var msg Msghdr 332 var rsa RawSockaddrAny 333 msg.Name = (*byte)(unsafe.Pointer(&rsa)) 334 msg.Namelen = uint32(SizeofSockaddrAny) 335 var iov Iovec 336 if len(p) > 0 { 337 iov.Base = (*byte)(unsafe.Pointer(&p[0])) 338 iov.SetLen(len(p)) 339 } 340 var dummy byte 341 if len(oob) > 0 { 342 // receive at least one normal byte 343 if len(p) == 0 { 344 iov.Base = &dummy 345 iov.SetLen(1) 346 } 347 msg.Control = (*byte)(unsafe.Pointer(&oob[0])) 348 msg.SetControllen(len(oob)) 349 } 350 msg.Iov = &iov 351 msg.Iovlen = 1 352 if n, err = recvmsg(fd, &msg, flags); err != nil { 353 return 354 } 355 oobn = int(msg.Controllen) 356 recvflags = int(msg.Flags) 357 // source address is only specified if the socket is unconnected 358 if rsa.Addr.Family != AF_UNSPEC { 359 from, err = anyToSockaddr(fd, &rsa) 360 } 361 return 362} 363 364//sys sendmsg(s int, msg *Msghdr, flags int) (n int, err error) 365 366func Sendmsg(fd int, p, oob []byte, to Sockaddr, flags int) (err error) { 367 _, err = SendmsgN(fd, p, oob, to, flags) 368 return 369} 370 371func SendmsgN(fd int, p, oob []byte, to Sockaddr, flags int) (n int, err error) { 372 var ptr unsafe.Pointer 373 var salen _Socklen 374 if to != nil { 375 ptr, salen, err = to.sockaddr() 376 if err != nil { 377 return 0, err 378 } 379 } 380 var msg Msghdr 381 msg.Name = (*byte)(unsafe.Pointer(ptr)) 382 msg.Namelen = uint32(salen) 383 var iov Iovec 384 if len(p) > 0 { 385 iov.Base = (*byte)(unsafe.Pointer(&p[0])) 386 iov.SetLen(len(p)) 387 } 388 var dummy byte 389 if len(oob) > 0 { 390 // send at least one normal byte 391 if len(p) == 0 { 392 iov.Base = &dummy 393 iov.SetLen(1) 394 } 395 msg.Control = (*byte)(unsafe.Pointer(&oob[0])) 396 msg.SetControllen(len(oob)) 397 } 398 msg.Iov = &iov 399 msg.Iovlen = 1 400 if n, err = sendmsg(fd, &msg, flags); err != nil { 401 return 0, err 402 } 403 if len(oob) > 0 && len(p) == 0 { 404 n = 0 405 } 406 return n, nil 407} 408 409//sys kevent(kq int, change unsafe.Pointer, nchange int, event unsafe.Pointer, nevent int, timeout *Timespec) (n int, err error) 410 411func Kevent(kq int, changes, events []Kevent_t, timeout *Timespec) (n int, err error) { 412 var change, event unsafe.Pointer 413 if len(changes) > 0 { 414 change = unsafe.Pointer(&changes[0]) 415 } 416 if len(events) > 0 { 417 event = unsafe.Pointer(&events[0]) 418 } 419 return kevent(kq, change, len(changes), event, len(events), timeout) 420} 421 422//sys sysctl(mib []_C_int, old *byte, oldlen *uintptr, new *byte, newlen uintptr) (err error) = SYS___SYSCTL 423 424// sysctlmib translates name to mib number and appends any additional args. 425func sysctlmib(name string, args ...int) ([]_C_int, error) { 426 // Translate name to mib number. 427 mib, err := nametomib(name) 428 if err != nil { 429 return nil, err 430 } 431 432 for _, a := range args { 433 mib = append(mib, _C_int(a)) 434 } 435 436 return mib, nil 437} 438 439func Sysctl(name string) (string, error) { 440 return SysctlArgs(name) 441} 442 443func SysctlArgs(name string, args ...int) (string, error) { 444 buf, err := SysctlRaw(name, args...) 445 if err != nil { 446 return "", err 447 } 448 n := len(buf) 449 450 // Throw away terminating NUL. 451 if n > 0 && buf[n-1] == '\x00' { 452 n-- 453 } 454 return string(buf[0:n]), nil 455} 456 457func SysctlUint32(name string) (uint32, error) { 458 return SysctlUint32Args(name) 459} 460 461func SysctlUint32Args(name string, args ...int) (uint32, error) { 462 mib, err := sysctlmib(name, args...) 463 if err != nil { 464 return 0, err 465 } 466 467 n := uintptr(4) 468 buf := make([]byte, 4) 469 if err := sysctl(mib, &buf[0], &n, nil, 0); err != nil { 470 return 0, err 471 } 472 if n != 4 { 473 return 0, EIO 474 } 475 return *(*uint32)(unsafe.Pointer(&buf[0])), nil 476} 477 478func SysctlUint64(name string, args ...int) (uint64, error) { 479 mib, err := sysctlmib(name, args...) 480 if err != nil { 481 return 0, err 482 } 483 484 n := uintptr(8) 485 buf := make([]byte, 8) 486 if err := sysctl(mib, &buf[0], &n, nil, 0); err != nil { 487 return 0, err 488 } 489 if n != 8 { 490 return 0, EIO 491 } 492 return *(*uint64)(unsafe.Pointer(&buf[0])), nil 493} 494 495func SysctlRaw(name string, args ...int) ([]byte, error) { 496 mib, err := sysctlmib(name, args...) 497 if err != nil { 498 return nil, err 499 } 500 501 // Find size. 502 n := uintptr(0) 503 if err := sysctl(mib, nil, &n, nil, 0); err != nil { 504 return nil, err 505 } 506 if n == 0 { 507 return nil, nil 508 } 509 510 // Read into buffer of that size. 511 buf := make([]byte, n) 512 if err := sysctl(mib, &buf[0], &n, nil, 0); err != nil { 513 return nil, err 514 } 515 516 // The actual call may return less than the original reported required 517 // size so ensure we deal with that. 518 return buf[:n], nil 519} 520 521//sys utimes(path string, timeval *[2]Timeval) (err error) 522 523func Utimes(path string, tv []Timeval) error { 524 if tv == nil { 525 return utimes(path, nil) 526 } 527 if len(tv) != 2 { 528 return EINVAL 529 } 530 return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0]))) 531} 532 533func UtimesNano(path string, ts []Timespec) error { 534 if ts == nil { 535 err := utimensat(AT_FDCWD, path, nil, 0) 536 if err != ENOSYS { 537 return err 538 } 539 return utimes(path, nil) 540 } 541 if len(ts) != 2 { 542 return EINVAL 543 } 544 // Darwin setattrlist can set nanosecond timestamps 545 err := setattrlistTimes(path, ts, 0) 546 if err != ENOSYS { 547 return err 548 } 549 err = utimensat(AT_FDCWD, path, (*[2]Timespec)(unsafe.Pointer(&ts[0])), 0) 550 if err != ENOSYS { 551 return err 552 } 553 // Not as efficient as it could be because Timespec and 554 // Timeval have different types in the different OSes 555 tv := [2]Timeval{ 556 NsecToTimeval(TimespecToNsec(ts[0])), 557 NsecToTimeval(TimespecToNsec(ts[1])), 558 } 559 return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0]))) 560} 561 562func UtimesNanoAt(dirfd int, path string, ts []Timespec, flags int) error { 563 if ts == nil { 564 return utimensat(dirfd, path, nil, flags) 565 } 566 if len(ts) != 2 { 567 return EINVAL 568 } 569 err := setattrlistTimes(path, ts, flags) 570 if err != ENOSYS { 571 return err 572 } 573 return utimensat(dirfd, path, (*[2]Timespec)(unsafe.Pointer(&ts[0])), flags) 574} 575 576//sys futimes(fd int, timeval *[2]Timeval) (err error) 577 578func Futimes(fd int, tv []Timeval) error { 579 if tv == nil { 580 return futimes(fd, nil) 581 } 582 if len(tv) != 2 { 583 return EINVAL 584 } 585 return futimes(fd, (*[2]Timeval)(unsafe.Pointer(&tv[0]))) 586} 587 588//sys fcntl(fd int, cmd int, arg int) (val int, err error) 589 590//sys poll(fds *PollFd, nfds int, timeout int) (n int, err error) 591 592func Poll(fds []PollFd, timeout int) (n int, err error) { 593 if len(fds) == 0 { 594 return poll(nil, 0, timeout) 595 } 596 return poll(&fds[0], len(fds), timeout) 597} 598 599// TODO: wrap 600// Acct(name nil-string) (err error) 601// Gethostuuid(uuid *byte, timeout *Timespec) (err error) 602// Ptrace(req int, pid int, addr uintptr, data int) (ret uintptr, err error) 603 604var mapper = &mmapper{ 605 active: make(map[*byte][]byte), 606 mmap: mmap, 607 munmap: munmap, 608} 609 610func Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) { 611 return mapper.Mmap(fd, offset, length, prot, flags) 612} 613 614func Munmap(b []byte) (err error) { 615 return mapper.Munmap(b) 616} 617 618//sys Madvise(b []byte, behav int) (err error) 619//sys Mlock(b []byte) (err error) 620//sys Mlockall(flags int) (err error) 621//sys Mprotect(b []byte, prot int) (err error) 622//sys Msync(b []byte, flags int) (err error) 623//sys Munlock(b []byte) (err error) 624//sys Munlockall() (err error) 625