// 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.
package runtime
import "unsafe"
type mOS struct {
machport uint32 // return address for mach ipc
waitsema uint32 // semaphore for parking on locks
}
var darwinVersion int
func bsdthread_create(stk, arg unsafe.Pointer, fn uintptr) int32
func bsdthread_register() int32
//go:noescape
func mach_msg_trap(h unsafe.Pointer, op int32, send_size, rcv_size, rcv_name, timeout, notify uint32) int32
func mach_reply_port() uint32
func mach_task_self() uint32
func mach_thread_self() uint32
//go:noescape
func sysctl(mib *uint32, miblen uint32, out *byte, size *uintptr, dst *byte, ndst uintptr) int32
func unimplemented(name string) {
println(name, "not implemented")
*(*int)(unsafe.Pointer(uintptr(1231))) = 1231
}
//go:nosplit
func semawakeup(mp *m) {
mach_semrelease(mp.waitsema)
}
//go:nosplit
func semacreate(mp *m) {
if mp.waitsema != 0 {
return
}
systemstack(func() {
mp.waitsema = mach_semcreate()
})
}
// BSD interface for threading.
func osinit() {
// bsdthread_register delayed until end of goenvs so that we
// can look at the environment first.
ncpu = getncpu()
physPageSize = getPageSize()
darwinVersion = getDarwinVersion()
}
const (
_CTL_KERN = 1
_CTL_HW = 6
_KERN_OSRELEASE = 2
_HW_NCPU = 3
_HW_PAGESIZE = 7
)
func getDarwinVersion() int {
// Use sysctl to fetch kern.osrelease
mib := [2]uint32{_CTL_KERN, _KERN_OSRELEASE}
var out [32]byte
nout := unsafe.Sizeof(out)
ret := sysctl(&mib[0], 2, (*byte)(unsafe.Pointer(&out)), &nout, nil, 0)
if ret >= 0 {
ver := 0
for i := 0; i < int(nout) && out[i] >= '0' && out[i] <= '9'; i++ {
ver *= 10
ver += int(out[i] - '0')
}
return ver
}
return 17 // should not happen: default to a newish version
}
func getncpu() int32 {
// Use sysctl to fetch hw.ncpu.
mib := [2]uint32{_CTL_HW, _HW_NCPU}
out := uint32(0)
nout := unsafe.Sizeof(out)
ret := sysctl(&mib[0], 2, (*byte)(unsafe.Pointer(&out)), &nout, nil, 0)
if ret >= 0 && int32(out) > 0 {
return int32(out)
}
return 1
}
func getPageSize() uintptr {
// Use sysctl to fetch hw.pagesize.
mib := [2]uint32{_CTL_HW, _HW_PAGESIZE}
out := uint32(0)
nout := unsafe.Sizeof(out)
ret := sysctl(&mib[0], 2, (*byte)(unsafe.Pointer(&out)), &nout, nil, 0)
if ret >= 0 && int32(out) > 0 {
return uintptr(out)
}
return 0
}
var urandom_dev = []byte("/dev/urandom\x00")
//go:nosplit
func getRandomData(r []byte) {
fd := open(&urandom_dev[0], 0 /* O_RDONLY */, 0)
n := read(fd, unsafe.Pointer(&r[0]), int32(len(r)))
closefd(fd)
extendRandom(r, int(n))
}
func goenvs() {
goenvs_unix()
// Register our thread-creation callback (see sys_darwin_{amd64,386}.s)
// but only if we're not using cgo. If we are using cgo we need
// to let the C pthread library install its own thread-creation callback.
if !iscgo {
if bsdthread_register() != 0 {
if gogetenv("DYLD_INSERT_LIBRARIES") != "" {
throw("runtime: bsdthread_register error (unset DYLD_INSERT_LIBRARIES)")
}
throw("runtime: bsdthread_register error")
}
}
}
// May run with m.p==nil, so write barriers are not allowed.
//go:nowritebarrier
func newosproc(mp *m, stk unsafe.Pointer) {
if false {
print("newosproc stk=", stk, " m=", mp, " g=", mp.g0, " id=", mp.id, " ostk=", &mp, "\n")
}
var oset sigset
sigprocmask(_SIG_SETMASK, &sigset_all, &oset)
errno := bsdthread_create(stk, unsafe.Pointer(mp), funcPC(mstart))
sigprocmask(_SIG_SETMASK, &oset, nil)
if errno < 0 {
print("runtime: failed to create new OS thread (have ", mcount(), " already; errno=", -errno, ")\n")
throw("runtime.newosproc")
}
}
// newosproc0 is a version of newosproc that can be called before the runtime
// is initialized.
//
// As Go uses bsdthread_register when running without cgo, this function is
// not safe to use after initialization as it does not pass an M as fnarg.
//
//go:nosplit
func newosproc0(stacksize uintptr, fn uintptr) {
stack := sysAlloc(stacksize, &memstats.stacks_sys)
if stack == nil {
write(2, unsafe.Pointer(&failallocatestack[0]), int32(len(failallocatestack)))
exit(1)
}
stk := unsafe.Pointer(uintptr(stack) + stacksize)
var oset sigset
sigprocmask(_SIG_SETMASK, &sigset_all, &oset)
errno := bsdthread_create(stk, nil, fn)
sigprocmask(_SIG_SETMASK, &oset, nil)
if errno < 0 {
write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate)))
exit(1)
}
}
var failallocatestack = []byte("runtime: failed to allocate stack for the new OS thread\n")
var failthreadcreate = []byte("runtime: failed to create new OS thread\n")
// Called to do synchronous initialization of Go code built with
// -buildmode=c-archive or -buildmode=c-shared.
// None of the Go runtime is initialized.
//go:nosplit
//go:nowritebarrierrec
func libpreinit() {
initsig(true)
}
// Called to initialize a new m (including the bootstrap m).
// Called on the parent thread (main thread in case of bootstrap), can allocate memory.
func mpreinit(mp *m) {
mp.gsignal = malg(32 * 1024) // OS X wants >= 8K
mp.gsignal.m = mp
}
// Called to initialize a new m (including the bootstrap m).
// Called on the new thread, cannot allocate memory.
func minit() {
// The alternate signal stack is buggy on arm and arm64.
// The signal handler handles it directly.
// The sigaltstack assembly function does nothing.
if GOARCH != "arm" && GOARCH != "arm64" {
minitSignalStack()
}
minitSignalMask()
}
// Called from dropm to undo the effect of an minit.
//go:nosplit
func unminit() {
// The alternate signal stack is buggy on arm and arm64.
// See minit.
if GOARCH != "arm" && GOARCH != "arm64" {
unminitSignals()
}
}
// Mach IPC, to get at semaphores
// Definitions are in /usr/include/mach on a Mac.
func macherror(r int32, fn string) {
print("mach error ", fn, ": ", r, "\n")
throw("mach error")
}
const _DebugMach = false
var zerondr machndr
func mach_msgh_bits(a, b uint32) uint32 {
return a | b<<8
}
func mach_msg(h *machheader, op int32, send_size, rcv_size, rcv_name, timeout, notify uint32) int32 {
// TODO: Loop on interrupt.
return mach_msg_trap(unsafe.Pointer(h), op, send_size, rcv_size, rcv_name, timeout, notify)
}
// Mach RPC (MIG)
const (
_MinMachMsg = 48
_MachReply = 100
)
type codemsg struct {
h machheader
ndr machndr
code int32
}
func machcall(h *machheader, maxsize int32, rxsize int32) int32 {
_g_ := getg()
port := _g_.m.machport
if port == 0 {
port = mach_reply_port()
_g_.m.machport = port
}
h.msgh_bits |= mach_msgh_bits(_MACH_MSG_TYPE_COPY_SEND, _MACH_MSG_TYPE_MAKE_SEND_ONCE)
h.msgh_local_port = port
h.msgh_reserved = 0
id := h.msgh_id
if _DebugMach {
p := (*[10000]unsafe.Pointer)(unsafe.Pointer(h))
print("send:\t")
var i uint32
for i = 0; i < h.msgh_size/uint32(unsafe.Sizeof(p[0])); i++ {
print(" ", p[i])
if i%8 == 7 {
print("\n\t")
}
}
if i%8 != 0 {
print("\n")
}
}
ret := mach_msg(h, _MACH_SEND_MSG|_MACH_RCV_MSG, h.msgh_size, uint32(maxsize), port, 0, 0)
if ret != 0 {
if _DebugMach {
print("mach_msg error ", ret, "\n")
}
return ret
}
if _DebugMach {
p := (*[10000]unsafe.Pointer)(unsafe.Pointer(h))
var i uint32
for i = 0; i < h.msgh_size/uint32(unsafe.Sizeof(p[0])); i++ {
print(" ", p[i])
if i%8 == 7 {
print("\n\t")
}
}
if i%8 != 0 {
print("\n")
}
}
if h.msgh_id != id+_MachReply {
if _DebugMach {
print("mach_msg _MachReply id mismatch ", h.msgh_id, " != ", id+_MachReply, "\n")
}
return -303 // MIG_REPLY_MISMATCH
}
// Look for a response giving the return value.
// Any call can send this back with an error,
// and some calls only have return values so they
// send it back on success too. I don't quite see how
// you know it's one of these and not the full response
// format, so just look if the message is right.
c := (*codemsg)(unsafe.Pointer(h))
if uintptr(h.msgh_size) == unsafe.Sizeof(*c) && h.msgh_bits&_MACH_MSGH_BITS_COMPLEX == 0 {
if _DebugMach {
print("mig result ", c.code, "\n")
}
return c.code
}
if h.msgh_size != uint32(rxsize) {
if _DebugMach {
print("mach_msg _MachReply size mismatch ", h.msgh_size, " != ", rxsize, "\n")
}
return -307 // MIG_ARRAY_TOO_LARGE
}
return 0
}
// Semaphores!
const (
tmach_semcreate = 3418
rmach_semcreate = tmach_semcreate + _MachReply
tmach_semdestroy = 3419
rmach_semdestroy = tmach_semdestroy + _MachReply
_KERN_ABORTED = 14
_KERN_OPERATION_TIMED_OUT = 49
)
type tmach_semcreatemsg struct {
h machheader
ndr machndr
policy int32
value int32
}
type rmach_semcreatemsg struct {
h machheader
body machbody
semaphore machport
}
type tmach_semdestroymsg struct {
h machheader
body machbody
semaphore machport
}
func mach_semcreate() uint32 {
var m [256]uint8
tx := (*tmach_semcreatemsg)(unsafe.Pointer(&m))
rx := (*rmach_semcreatemsg)(unsafe.Pointer(&m))
tx.h.msgh_bits = 0
tx.h.msgh_size = uint32(unsafe.Sizeof(*tx))
tx.h.msgh_remote_port = mach_task_self()
tx.h.msgh_id = tmach_semcreate
tx.ndr = zerondr
tx.policy = 0 // 0 = SYNC_POLICY_FIFO
tx.value = 0
for {
r := machcall(&tx.h, int32(unsafe.Sizeof(m)), int32(unsafe.Sizeof(*rx)))
if r == 0 {
break
}
if r == _KERN_ABORTED { // interrupted
continue
}
macherror(r, "semaphore_create")
}
if rx.body.msgh_descriptor_count != 1 {
unimplemented("mach_semcreate desc count")
}
return rx.semaphore.name
}
func mach_semdestroy(sem uint32) {
var m [256]uint8
tx := (*tmach_semdestroymsg)(unsafe.Pointer(&m))
tx.h.msgh_bits = _MACH_MSGH_BITS_COMPLEX
tx.h.msgh_size = uint32(unsafe.Sizeof(*tx))
tx.h.msgh_remote_port = mach_task_self()
tx.h.msgh_id = tmach_semdestroy
tx.body.msgh_descriptor_count = 1
tx.semaphore.name = sem
tx.semaphore.disposition = _MACH_MSG_TYPE_MOVE_SEND
tx.semaphore._type = 0
for {
r := machcall(&tx.h, int32(unsafe.Sizeof(m)), 0)
if r == 0 {
break
}
if r == _KERN_ABORTED { // interrupted
continue
}
macherror(r, "semaphore_destroy")
}
}
// The other calls have simple system call traps in sys_darwin_{amd64,386}.s
func mach_semaphore_wait(sema uint32) int32
func mach_semaphore_timedwait(sema, sec, nsec uint32) int32
func mach_semaphore_signal(sema uint32) int32
func mach_semaphore_signal_all(sema uint32) int32
func semasleep1(ns int64) int32 {
_g_ := getg()
if ns >= 0 {
var nsecs int32
secs := timediv(ns, 1000000000, &nsecs)
r := mach_semaphore_timedwait(_g_.m.waitsema, uint32(secs), uint32(nsecs))
if r == _KERN_ABORTED || r == _KERN_OPERATION_TIMED_OUT {
return -1
}
if r != 0 {
macherror(r, "semaphore_wait")
}
return 0
}
for {
r := mach_semaphore_wait(_g_.m.waitsema)
if r == 0 {
break
}
// Note: We don't know how this call (with no timeout) can get _KERN_OPERATION_TIMED_OUT,
// but it does reliably, though at a very low rate, on OS X 10.8, 10.9, 10.10, and 10.11.
// See golang.org/issue/17161.
if r == _KERN_ABORTED || r == _KERN_OPERATION_TIMED_OUT { // interrupted
continue
}
macherror(r, "semaphore_wait")
}
return 0
}
//go:nosplit
func semasleep(ns int64) int32 {
var r int32
systemstack(func() {
r = semasleep1(ns)
})
return r
}
//go:nosplit
func mach_semrelease(sem uint32) {
for {
r := mach_semaphore_signal(sem)
if r == 0 {
break
}
if r == _KERN_ABORTED { // interrupted
continue
}
// mach_semrelease must be completely nosplit,
// because it is called from Go code.
// If we're going to die, start that process on the system stack
// to avoid a Go stack split.
systemstack(func() { macherror(r, "semaphore_signal") })
}
}
//go:nosplit
func osyield() {
usleep(1)
}
func memlimit() uintptr {
// NOTE(rsc): Could use getrlimit here,
// like on FreeBSD or Linux, but Darwin doesn't enforce
// ulimit -v, so it's unclear why we'd try to stay within
// the limit.
return 0
}
const (
_NSIG = 32
_SI_USER = 0 /* empirically true, but not what headers say */
_SIG_BLOCK = 1
_SIG_UNBLOCK = 2
_SIG_SETMASK = 3
_SS_DISABLE = 4
)
//go:noescape
func sigprocmask(how int32, new, old *sigset)
//go:noescape
func sigaction(mode uint32, new *sigactiont, old *usigactiont)
//go:noescape
func sigaltstack(new, old *stackt)
// darwin/arm64 uses registers instead of stack-based arguments.
// TODO: does this matter?
func sigtramp(fn uintptr, infostyle, sig uint32, info *siginfo, ctx unsafe.Pointer)
//go:noescape
func setitimer(mode int32, new, old *itimerval)
func raise(sig uint32)
func raiseproc(sig uint32)
//extern SigTabTT runtime·sigtab[];
type sigset uint32
var sigset_all = ^sigset(0)
//go:nosplit
//go:nowritebarrierrec
func setsig(i uint32, fn uintptr) {
var sa sigactiont
sa.sa_flags = _SA_SIGINFO | _SA_ONSTACK | _SA_RESTART
sa.sa_mask = ^uint32(0)
sa.sa_tramp = unsafe.Pointer(funcPC(sigtramp)) // runtime·sigtramp's job is to call into real handler
*(*uintptr)(unsafe.Pointer(&sa.__sigaction_u)) = fn
sigaction(i, &sa, nil)
}
//go:nosplit
//go:nowritebarrierrec
func setsigstack(i uint32) {
var osa usigactiont
sigaction(i, nil, &osa)
handler := *(*uintptr)(unsafe.Pointer(&osa.__sigaction_u))
if osa.sa_flags&_SA_ONSTACK != 0 {
return
}
var sa sigactiont
*(*uintptr)(unsafe.Pointer(&sa.__sigaction_u)) = handler
sa.sa_tramp = unsafe.Pointer(funcPC(sigtramp))
sa.sa_mask = osa.sa_mask
sa.sa_flags = osa.sa_flags | _SA_ONSTACK
sigaction(i, &sa, nil)
}
//go:nosplit
//go:nowritebarrierrec
func getsig(i uint32) uintptr {
var sa usigactiont
sigaction(i, nil, &sa)
return *(*uintptr)(unsafe.Pointer(&sa.__sigaction_u))
}
// setSignaltstackSP sets the ss_sp field of a stackt.
//go:nosplit
func setSignalstackSP(s *stackt, sp uintptr) {
*(*uintptr)(unsafe.Pointer(&s.ss_sp)) = sp
}
//go:nosplit
//go:nowritebarrierrec
func sigaddset(mask *sigset, i int) {
*mask |= 1 << (uint32(i) - 1)
}
func sigdelset(mask *sigset, i int) {
*mask &^= 1 << (uint32(i) - 1)
}
//go:linkname executablePath os.executablePath
var executablePath string
func sysargs(argc int32, argv **byte) {
// skip over argv, envv and the first string will be the path
n := argc + 1
for argv_index(argv, n) != nil {
n++
}
executablePath = gostringnocopy(argv_index(argv, n+1))
// strip "executable_path=" prefix if available, it's added after OS X 10.11.
const prefix = "executable_path="
if len(executablePath) > len(prefix) && executablePath[:len(prefix)] == prefix {
executablePath = executablePath[len(prefix):]
}
}