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// 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
}
//go:noescape
//extern mach_msg_trap
func mach_msg_trap(h unsafe.Pointer, op int32, send_size, rcv_size, rcv_name, timeout, notify uint32) int32
//extern mach_reply_port
func mach_reply_port() uint32
//extern mach_task_self
func mach_task_self() uint32
func unimplemented(name string) {
println(name, "not implemented")
*(*int)(unsafe.Pointer(uintptr(1231))) = 1231
}
//go:nosplit
func semawakeup(mp *m) {
mach_semrelease(mp.mos.waitsema)
}
//go:nosplit
func semacreate(mp *m) {
if mp.mos.waitsema != 0 {
return
}
systemstack(func() {
mp.mos.waitsema = mach_semcreate()
})
}
// 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.mos.machport
if port == 0 {
port = mach_reply_port()
_g_.m.mos.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")
}
}
//extern semaphore_wait
func mach_semaphore_wait(sema uint32) int32
//extern semaphore_timedwait
func mach_semaphore_timedwait(sema, sec, nsec uint32) int32
//extern semaphore_signal
func mach_semaphore_signal(sema uint32) int32
//extern semaphore_signal_all
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.mos.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.mos.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
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") })
}
}
type machheader struct {
msgh_bits uint32
msgh_size uint32
msgh_remote_port uint32
msgh_local_port uint32
msgh_reserved uint32
msgh_id int32
}
type machndr struct {
mig_vers uint8
if_vers uint8
reserved1 uint8
mig_encoding uint8
int_rep uint8
char_rep uint8
float_rep uint8
reserved2 uint8
}
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