1 files changed, 265 insertions, 0 deletions
diff --git a/src/runtime/os1_netbsd.go b/src/runtime/os1_netbsd.go
new file mode 100644
index 000000000..493be30fa
--- /dev/null
+++ b/src/runtime/os1_netbsd.go
@@ -0,0 +1,265 @@
+// Copyright 2011 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"
+
+const (
+	_ESRCH   = 3
+	_ENOTSUP = 91
+
+	// From NetBSD's <sys/time.h>
+	_CLOCK_REALTIME  = 0
+	_CLOCK_VIRTUAL   = 1
+	_CLOCK_PROF      = 2
+	_CLOCK_MONOTONIC = 3
+)
+
+var sigset_none = sigset{}
+var sigset_all = sigset{[4]uint32{^uint32(0), ^uint32(0), ^uint32(0), ^uint32(0)}}
+
+// From NetBSD's <sys/sysctl.h>
+const (
+	_CTL_HW  = 6
+	_HW_NCPU = 3
+)
+
+func getncpu() int32 {
+	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 {
+		return int32(out)
+	}
+	return 1
+}
+
+//go:nosplit
+func semacreate() uintptr {
+	return 1
+}
+
+//go:nosplit
+func semasleep(ns int64) int32 {
+	_g_ := getg()
+
+	// spin-mutex lock
+	for {
+		if xchg(&_g_.m.waitsemalock, 1) == 0 {
+			break
+		}
+		osyield()
+	}
+
+	for {
+		// lock held
+		if _g_.m.waitsemacount == 0 {
+			// sleep until semaphore != 0 or timeout.
+			// thrsleep unlocks m.waitsemalock.
+			if ns < 0 {
+				// TODO(jsing) - potential deadlock!
+				//
+				// There is a potential deadlock here since we
+				// have to release the waitsemalock mutex
+				// before we call lwp_park() to suspend the
+				// thread. This allows another thread to
+				// release the lock and call lwp_unpark()
+				// before the thread is actually suspended.
+				// If this occurs the current thread will end
+				// up sleeping indefinitely. Unfortunately
+				// the NetBSD kernel does not appear to provide
+				// a mechanism for unlocking the userspace
+				// mutex once the thread is actually parked.
+				atomicstore(&_g_.m.waitsemalock, 0)
+				lwp_park(nil, 0, unsafe.Pointer(&_g_.m.waitsemacount), nil)
+			} else {
+				var ts timespec
+				var nsec int32
+				ns += nanotime()
+				ts.set_sec(timediv(ns, 1000000000, &nsec))
+				ts.set_nsec(nsec)
+				// TODO(jsing) - potential deadlock!
+				// See above for details.
+				atomicstore(&_g_.m.waitsemalock, 0)
+				lwp_park(&ts, 0, unsafe.Pointer(&_g_.m.waitsemacount), nil)
+			}
+			// reacquire lock
+			for {
+				if xchg(&_g_.m.waitsemalock, 1) == 0 {
+					break
+				}
+				osyield()
+			}
+		}
+
+		// lock held (again)
+		if _g_.m.waitsemacount != 0 {
+			// semaphore is available.
+			_g_.m.waitsemacount--
+			// spin-mutex unlock
+			atomicstore(&_g_.m.waitsemalock, 0)
+			return 0
+		}
+
+		// semaphore not available.
+		// if there is a timeout, stop now.
+		// otherwise keep trying.
+		if ns >= 0 {
+			break
+		}
+	}
+
+	// lock held but giving up
+	// spin-mutex unlock
+	atomicstore(&_g_.m.waitsemalock, 0)
+	return -1
+}
+
+//go:nosplit
+func semawakeup(mp *m) {
+	// spin-mutex lock
+	for {
+		if xchg(&mp.waitsemalock, 1) == 0 {
+			break
+		}
+		osyield()
+	}
+
+	mp.waitsemacount++
+	// TODO(jsing) - potential deadlock, see semasleep() for details.
+	// Confirm that LWP is parked before unparking...
+	ret := lwp_unpark(int32(mp.procid), unsafe.Pointer(&mp.waitsemacount))
+	if ret != 0 && ret != _ESRCH {
+		// semawakeup can be called on signal stack.
+		systemstack(func() {
+			print("thrwakeup addr=", &mp.waitsemacount, " sem=", mp.waitsemacount, " ret=", ret, "\n")
+		})
+	}
+
+	// spin-mutex unlock
+	atomicstore(&mp.waitsemalock, 0)
+}
+
+func newosproc(mp *m, stk unsafe.Pointer) {
+	if false {
+		print("newosproc stk=", stk, " m=", mp, " g=", mp.g0, " id=", mp.id, "/", int32(mp.tls[0]), " ostk=", &mp, "\n")
+	}
+
+	mp.tls[0] = uintptr(mp.id) // so 386 asm can find it
+
+	var uc ucontextt
+	getcontext(unsafe.Pointer(&uc))
+
+	uc.uc_flags = _UC_SIGMASK | _UC_CPU
+	uc.uc_link = nil
+	uc.uc_sigmask = sigset_all
+
+	lwp_mcontext_init(&uc.uc_mcontext, stk, mp, mp.g0, funcPC(mstart))
+
+	ret := lwp_create(unsafe.Pointer(&uc), 0, unsafe.Pointer(&mp.procid))
+	if ret < 0 {
+		print("runtime: failed to create new OS thread (have ", mcount()-1, " already; errno=", -ret, ")\n")
+		gothrow("runtime.newosproc")
+	}
+}
+
+func osinit() {
+	ncpu = getncpu()
+}
+
+var urandom_data [_HashRandomBytes]byte
+var urandom_dev = []byte("/dev/urandom\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()
+}
+
+// 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)
+	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() {
+	_g_ := getg()
+	_g_.m.procid = uint64(lwp_self())
+
+	// Initialize signal handling
+	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)
+}
+
+func memlimit() uintptr {
+	return 0
+}
+
+func sigtramp()
+
+type sigactiont struct {
+	sa_sigaction uintptr
+	sa_mask      sigset
+	sa_flags     int32
+}
+
+func setsig(i int32, fn uintptr, restart bool) {
+	var sa sigactiont
+	sa.sa_flags = _SA_SIGINFO | _SA_ONSTACK
+	if restart {
+		sa.sa_flags |= _SA_RESTART
+	}
+	sa.sa_mask = sigset_all
+	if fn == funcPC(sighandler) {
+		fn = funcPC(sigtramp)
+	}
+	sa.sa_sigaction = fn
+	sigaction(i, &sa, nil)
+}
+
+func getsig(i int32) uintptr {
+	var sa sigactiont
+	sigaction(i, nil, &sa)
+	if sa.sa_sigaction == funcPC(sigtramp) {
+		return funcPC(sighandler)
+	}
+	return sa.sa_sigaction
+}
+
+func signalstack(p *byte, n int32) {
+	var st sigaltstackt
+
+	st.ss_sp = uintptr(unsafe.Pointer(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)
+}