[dev.cc] runtime: convert operating system support code from C to Go
The conversion was done with an automated tool and then
modified only as necessary to make it compile and run.
[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]
LGTM=r
R=r
CC=austin, dvyukov, golang-codereviews, iant, khr
https://golang.org/cl/174830044
diff --git a/src/runtime/os1_darwin.go b/src/runtime/os1_darwin.go
new file mode 100644
index 0000000..b30ffbe
--- /dev/null
+++ b/src/runtime/os1_darwin.go
@@ -0,0 +1,423 @@
+// 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"
+
+//extern SigTabTT runtime·sigtab[];
+
+var sigset_none = uint32(0)
+var sigset_all = ^uint32(0)
+
+func unimplemented(name string) {
+ println(name, "not implemented")
+ *(*int)(unsafe.Pointer(uintptr(1231))) = 1231
+}
+
+//go:nosplit
+func semawakeup(mp *m) {
+ mach_semrelease(uint32(mp.waitsema))
+}
+
+//go:nosplit
+func semacreate() uintptr {
+ var x uintptr
+ onM(func() {
+ x = uintptr(mach_semcreate())
+ })
+ return x
+}
+
+// BSD interface for threading.
+func osinit() {
+ // bsdthread_register delayed until end of goenvs so that we
+ // can look at the environment first.
+
+ // Use sysctl to fetch hw.ncpu.
+ mib := [2]uint32{6, 3}
+ out := uint32(0)
+ nout := unsafe.Sizeof(out)
+ ret := sysctl(&mib[0], 2, (*byte)(unsafe.Pointer(&out)), &nout, nil, 0)
+ if ret >= 0 {
+ ncpu = int32(out)
+ }
+}
+
+var urandom_data [_HashRandomBytes]byte
+var urandom_dev = []byte("/dev/random\x00")
+
+//go:nosplit
+func get_random_data(rnd *unsafe.Pointer, rnd_len *int32) {
+ fd := open(&urandom_dev[0], 0 /* O_RDONLY */, 0)
+ if read(fd, unsafe.Pointer(&urandom_data), _HashRandomBytes) == _HashRandomBytes {
+ *rnd = unsafe.Pointer(&urandom_data[0])
+ *rnd_len = _HashRandomBytes
+ } else {
+ *rnd = nil
+ *rnd_len = 0
+ }
+ close(fd)
+}
+
+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") != "" {
+ gothrow("runtime: bsdthread_register error (unset DYLD_INSERT_LIBRARIES)")
+ }
+ gothrow("runtime: bsdthread_register error")
+ }
+ }
+}
+
+func newosproc(mp *m, stk unsafe.Pointer) {
+ mp.tls[0] = uintptr(mp.id) // so 386 asm can find it
+ if false {
+ print("newosproc stk=", stk, " m=", mp, " g=", mp.g0, " id=", mp.id, "/", int(mp.tls[0]), " ostk=", &mp, "\n")
+ }
+
+ var oset uint32
+ sigprocmask(_SIG_SETMASK, &sigset_all, &oset)
+ errno := bsdthread_create(stk, mp, mp.g0, funcPC(mstart))
+ sigprocmask(_SIG_SETMASK, &oset, nil)
+
+ if errno < 0 {
+ print("runtime: failed to create new OS thread (have ", mcount(), " already; errno=", -errno, ")\n")
+ gothrow("runtime.newosproc")
+ }
+}
+
+// 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, can not allocate memory.
+func minit() {
+ // Initialize signal handling.
+ _g_ := getg()
+ signalstack((*byte)(unsafe.Pointer(_g_.m.gsignal.stack.lo)), 32*1024)
+ sigprocmask(_SIG_SETMASK, &sigset_none, nil)
+}
+
+// Called from dropm to undo the effect of an minit.
+func unminit() {
+ signalstack(nil, 0)
+}
+
+// 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")
+ gothrow("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(uint32(_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(uint32(_g_.m.waitsema))
+ if r == 0 {
+ break
+ }
+ if r == _KERN_ABORTED { // interrupted
+ continue
+ }
+ macherror(r, "semaphore_wait")
+ }
+ return 0
+}
+
+//go:nosplit
+func semasleep(ns int64) int32 {
+ var r int32
+ onM(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 m stack
+ // to avoid a Go stack split.
+ onM_signalok(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
+}
+
+func setsig(i int32, fn uintptr, restart bool) {
+ var sa sigactiont
+ memclr(unsafe.Pointer(&sa), unsafe.Sizeof(sa))
+ sa.sa_flags = _SA_SIGINFO | _SA_ONSTACK
+ if restart {
+ sa.sa_flags |= _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(uint32(i), &sa, nil)
+}
+
+func getsig(i int32) uintptr {
+ var sa sigactiont
+ memclr(unsafe.Pointer(&sa), unsafe.Sizeof(sa))
+ sigaction(uint32(i), nil, &sa)
+ return *(*uintptr)(unsafe.Pointer(&sa.__sigaction_u))
+}
+
+func signalstack(p *byte, n int32) {
+ var st stackt
+ st.ss_sp = p
+ st.ss_size = uintptr(n)
+ st.ss_flags = 0
+ if p == nil {
+ st.ss_flags = _SS_DISABLE
+ }
+ sigaltstack(&st, nil)
+}
+
+func unblocksignals() {
+ sigprocmask(_SIG_SETMASK, &sigset_none, nil)
+}
