Revert "runtime: use a proper type, sigset, for m.sigmask"

This reverts commit 7db77271.

Change-Id: I6d8855eb05ca331025dc49a5533c6da4d1fa4e84
Reviewed-on: https://go-review.googlesource.com/17030Reviewed-by: Russ Cox <rsc@golang.org>

src/runtime/os1_darwin.go

@@ -8,9 +8,7 @@ import "unsafe"
 
 //extern SigTabTT runtime·sigtab[];
 
-type sigset uint32
-
-var sigset_all = ^sigset(0)
+var sigset_all = ^uint32(0)
 
 func unimplemented(name string) {
 	println(name, "not implemented")
@@ -85,7 +83,7 @@ func newosproc(mp *m, stk unsafe.Pointer) {
 		print("newosproc stk=", stk, " m=", mp, " g=", mp.g0, " id=", mp.id, " ostk=", &mp, "\n")
 	}
 
-	var oset sigset
+	var oset uint32
 	sigprocmask(_SIG_SETMASK, &sigset_all, &oset)
 	errno := bsdthread_create(stk, unsafe.Pointer(mp), funcPC(mstart))
 	sigprocmask(_SIG_SETMASK, &oset, nil)
@@ -111,7 +109,7 @@ func newosproc0(stacksize uintptr, fn unsafe.Pointer, fnarg uintptr) {
 	}
 	stk := unsafe.Pointer(uintptr(stack) + stacksize)
 
-	var oset sigset
+	var oset uint32
 	sigprocmask(_SIG_SETMASK, &sigset_all, &oset)
 	errno := bsdthread_create(stk, fn, fnarg)
 	sigprocmask(_SIG_SETMASK, &oset, nil)
@@ -133,7 +131,11 @@ func mpreinit(mp *m) {
 }
 
 func msigsave(mp *m) {
-	sigprocmask(_SIG_SETMASK, nil, &mp.sigmask)
+	smask := (*uint32)(unsafe.Pointer(&mp.sigmask))
+	if unsafe.Sizeof(*smask) > unsafe.Sizeof(mp.sigmask) {
+		throw("insufficient storage for signal mask")
+	}
+	sigprocmask(_SIG_SETMASK, nil, smask)
 }
 
 // Called to initialize a new m (including the bootstrap m).
@@ -144,7 +146,7 @@ func minit() {
 	signalstack(&_g_.m.gsignal.stack)
 
 	// restore signal mask from m.sigmask and unblock essential signals
-	nmask := _g_.m.sigmask
+	nmask := *(*uint32)(unsafe.Pointer(&_g_.m.sigmask))
 	for i := range sigtable {
 		if sigtable[i].flags&_SigUnblock != 0 {
 			nmask &^= 1 << (uint32(i) - 1)
@@ -156,7 +158,8 @@ func minit() {
 // Called from dropm to undo the effect of an minit.
 func unminit() {
 	_g_ := getg()
-	sigprocmask(_SIG_SETMASK, &_g_.m.sigmask, nil)
+	smask := (*uint32)(unsafe.Pointer(&_g_.m.sigmask))
+	sigprocmask(_SIG_SETMASK, smask, nil)
 	signalstack(nil)
 }
 
@@ -469,11 +472,10 @@ func signalstack(s *stack) {
 }
 
 func updatesigmask(m sigmask) {
-	s := sigset(m[0])
-	sigprocmask(_SIG_SETMASK, &s, nil)
+	sigprocmask(_SIG_SETMASK, &m[0], nil)
 }
 
 func unblocksig(sig int32) {
-	mask := sigset(1) << (uint32(sig) - 1)
+	mask := uint32(1) << (uint32(sig) - 1)
 	sigprocmask(_SIG_UNBLOCK, &mask, nil)
 }

src/runtime/os1_dragonfly.go

@@ -118,7 +118,11 @@ func mpreinit(mp *m) {
 }
 
 func msigsave(mp *m) {
-	sigprocmask(_SIG_SETMASK, nil, &mp.sigmask)
+	smask := (*sigset)(unsafe.Pointer(&mp.sigmask))
+	if unsafe.Sizeof(*smask) > unsafe.Sizeof(mp.sigmask) {
+		throw("insufficient storage for signal mask")
+	}
+	sigprocmask(_SIG_SETMASK, nil, smask)
 }
 
 // Called to initialize a new m (including the bootstrap m).
@@ -133,7 +137,7 @@ func minit() {
 	signalstack(&_g_.m.gsignal.stack)
 
 	// restore signal mask from m.sigmask and unblock essential signals
-	nmask := _g_.m.sigmask
+	nmask := *(*sigset)(unsafe.Pointer(&_g_.m.sigmask))
 	for i := range sigtable {
 		if sigtable[i].flags&_SigUnblock != 0 {
 			nmask.__bits[(i-1)/32] &^= 1 << ((uint32(i) - 1) & 31)
@@ -145,7 +149,8 @@ func minit() {
 // Called from dropm to undo the effect of an minit.
 func unminit() {
 	_g_ := getg()
-	sigprocmask(_SIG_SETMASK, &_g_.m.sigmask, nil)
+	smask := (*sigset)(unsafe.Pointer(&_g_.m.sigmask))
+	sigprocmask(_SIG_SETMASK, smask, nil)
 	signalstack(nil)
 }
 

src/runtime/os1_freebsd.go

@@ -121,7 +121,11 @@ func mpreinit(mp *m) {
 }
 
 func msigsave(mp *m) {
-	sigprocmask(_SIG_SETMASK, nil, &mp.sigmask)
+	smask := (*sigset)(unsafe.Pointer(&mp.sigmask))
+	if unsafe.Sizeof(*smask) > unsafe.Sizeof(mp.sigmask) {
+		throw("insufficient storage for signal mask")
+	}
+	sigprocmask(_SIG_SETMASK, nil, smask)
 }
 
 // Called to initialize a new m (including the bootstrap m).
@@ -139,7 +143,7 @@ func minit() {
 	signalstack(&_g_.m.gsignal.stack)
 
 	// restore signal mask from m.sigmask and unblock essential signals
-	nmask := _g_.m.sigmask
+	nmask := *(*sigset)(unsafe.Pointer(&_g_.m.sigmask))
 	for i := range sigtable {
 		if sigtable[i].flags&_SigUnblock != 0 {
 			nmask.__bits[(i-1)/32] &^= 1 << ((uint32(i) - 1) & 31)
@@ -151,7 +155,8 @@ func minit() {
 // Called from dropm to undo the effect of an minit.
 func unminit() {
 	_g_ := getg()
-	sigprocmask(_SIG_SETMASK, &_g_.m.sigmask, nil)
+	smask := (*sigset)(unsafe.Pointer(&_g_.m.sigmask))
+	sigprocmask(_SIG_SETMASK, smask, nil)
 	signalstack(nil)
 }
 

src/runtime/os1_linux.go

@@ -198,7 +198,10 @@ func mpreinit(mp *m) {
 }
 
 func msigsave(mp *m) {
-	smask := &mp.sigmask
+	smask := (*sigset)(unsafe.Pointer(&mp.sigmask))
+	if unsafe.Sizeof(*smask) > unsafe.Sizeof(mp.sigmask) {
+		throw("insufficient storage for signal mask")
+	}
 	rtsigprocmask(_SIG_SETMASK, nil, smask, int32(unsafe.Sizeof(*smask)))
 }
 
@@ -215,7 +218,7 @@ func minit() {
 	_g_.m.procid = uint64(gettid())
 
 	// restore signal mask from m.sigmask and unblock essential signals
-	nmask := _g_.m.sigmask
+	nmask := *(*sigset)(unsafe.Pointer(&_g_.m.sigmask))
 	for i := range sigtable {
 		if sigtable[i].flags&_SigUnblock != 0 {
 			sigdelset(&nmask, i)
@@ -227,7 +230,7 @@ func minit() {
 // Called from dropm to undo the effect of an minit.
 func unminit() {
 	_g_ := getg()
-	smask := &_g_.m.sigmask
+	smask := (*sigset)(unsafe.Pointer(&_g_.m.sigmask))
 	rtsigprocmask(_SIG_SETMASK, smask, nil, int32(unsafe.Sizeof(*smask)))
 	signalstack(nil)
 }

src/runtime/os1_nacl.go

@@ -6,8 +6,6 @@ package runtime
 
 import "unsafe"
 
-type sigset struct{}
-
 // 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) {

src/runtime/os1_netbsd.go

@@ -139,7 +139,11 @@ func mpreinit(mp *m) {
 }
 
 func msigsave(mp *m) {
-	sigprocmask(_SIG_SETMASK, nil, &mp.sigmask)
+	smask := (*sigset)(unsafe.Pointer(&mp.sigmask))
+	if unsafe.Sizeof(*smask) > unsafe.Sizeof(mp.sigmask) {
+		throw("insufficient storage for signal mask")
+	}
+	sigprocmask(_SIG_SETMASK, nil, smask)
 }
 
 // Called to initialize a new m (including the bootstrap m).
@@ -152,7 +156,7 @@ func minit() {
 	signalstack(&_g_.m.gsignal.stack)
 
 	// restore signal mask from m.sigmask and unblock essential signals
-	nmask := _g_.m.sigmask
+	nmask := *(*sigset)(unsafe.Pointer(&_g_.m.sigmask))
 	for i := range sigtable {
 		if sigtable[i].flags&_SigUnblock != 0 {
 			nmask.__bits[(i-1)/32] &^= 1 << ((uint32(i) - 1) & 31)
@@ -164,7 +168,8 @@ func minit() {
 // Called from dropm to undo the effect of an minit.
 func unminit() {
 	_g_ := getg()
-	sigprocmask(_SIG_SETMASK, &_g_.m.sigmask, nil)
+	smask := (*sigset)(unsafe.Pointer(&_g_.m.sigmask))
+	sigprocmask(_SIG_SETMASK, smask, nil)
 
 	signalstack(nil)
 }

src/runtime/os1_openbsd.go

@@ -22,11 +22,9 @@ const (
 	_CLOCK_MONOTONIC = 3
 )
 
-type sigset uint32
-
 const (
-	sigset_none = sigset(0)
-	sigset_all  = ^sigset(0)
+	sigset_none = uint32(0)
+	sigset_all  = ^uint32(0)
 )
 
 // From OpenBSD's <sys/sysctl.h>
@@ -151,7 +149,11 @@ func mpreinit(mp *m) {
 }
 
 func msigsave(mp *m) {
-	mp.sigmask = sigprocmask(_SIG_BLOCK, 0)
+	smask := (*uint32)(unsafe.Pointer(&mp.sigmask))
+	if unsafe.Sizeof(*smask) > unsafe.Sizeof(mp.sigmask) {
+		throw("insufficient storage for signal mask")
+	}
+	*smask = sigprocmask(_SIG_BLOCK, 0)
 }
 
 // Called to initialize a new m (including the bootstrap m).
@@ -166,7 +168,7 @@ func minit() {
 	signalstack(&_g_.m.gsignal.stack)
 
 	// restore signal mask from m.sigmask and unblock essential signals
-	nmask := _g_.m.sigmask
+	nmask := *(*uint32)(unsafe.Pointer(&_g_.m.sigmask))
 	for i := range sigtable {
 		if sigtable[i].flags&_SigUnblock != 0 {
 			nmask &^= 1 << (uint32(i) - 1)
@@ -178,7 +180,8 @@ func minit() {
 // Called from dropm to undo the effect of an minit.
 func unminit() {
 	_g_ := getg()
-	sigprocmask(_SIG_SETMASK, _g_.m.sigmask)
+	smask := *(*uint32)(unsafe.Pointer(&_g_.m.sigmask))
+	sigprocmask(_SIG_SETMASK, smask)
 	signalstack(nil)
 }
 
@@ -200,7 +203,7 @@ func setsig(i int32, fn uintptr, restart bool) {
 	if restart {
 		sa.sa_flags |= _SA_RESTART
 	}
-	sa.sa_mask = uint32(sigset_all)
+	sa.sa_mask = sigset_all
 	if fn == funcPC(sighandler) {
 		fn = funcPC(sigtramp)
 	}
@@ -234,10 +237,10 @@ func signalstack(s *stack) {
 }
 
 func updatesigmask(m sigmask) {
-	sigprocmask(_SIG_SETMASK, sigset(m[0]))
+	sigprocmask(_SIG_SETMASK, m[0])
 }
 
 func unblocksig(sig int32) {
-	mask := sigset(1) << (uint32(sig) - 1)
+	mask := uint32(1) << (uint32(sig) - 1)
 	sigprocmask(_SIG_UNBLOCK, mask)
 }

src/runtime/os1_plan9.go

@@ -9,8 +9,6 @@ import (
 	"unsafe"
 )
 
-type sigset struct{}
-
 // 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) {

src/runtime/os1_windows.go

@@ -99,8 +99,6 @@ var (
 	_GetQueuedCompletionStatusEx stdFunction
 )
 
-type sigset struct{}
-
 // Call a Windows function with stdcall conventions,
 // and switch to os stack during the call.
 func asmstdcall(fn unsafe.Pointer)

src/runtime/os3_solaris.go

@@ -193,7 +193,11 @@ func mpreinit(mp *m) {
 func miniterrno()
 
 func msigsave(mp *m) {
-	sigprocmask(_SIG_SETMASK, nil, &mp.sigmask)
+	smask := (*sigset)(unsafe.Pointer(&mp.sigmask))
+	if unsafe.Sizeof(*smask) > unsafe.Sizeof(mp.sigmask) {
+		throw("insufficient storage for signal mask")
+	}
+	sigprocmask(_SIG_SETMASK, nil, smask)
 }
 
 // Called to initialize a new m (including the bootstrap m).
@@ -205,7 +209,7 @@ func minit() {
 	signalstack(&_g_.m.gsignal.stack)
 
 	// restore signal mask from m.sigmask and unblock essential signals
-	nmask := _g_.m.sigmask
+	nmask := *(*sigset)(unsafe.Pointer(&_g_.m.sigmask))
 	for i := range sigtable {
 		if sigtable[i].flags&_SigUnblock != 0 {
 			nmask.__sigbits[(i-1)/32] &^= 1 << ((uint32(i) - 1) & 31)
@@ -217,7 +221,8 @@ func minit() {
 // Called from dropm to undo the effect of an minit.
 func unminit() {
 	_g_ := getg()
-	sigprocmask(_SIG_SETMASK, &_g_.m.sigmask, nil)
+	smask := (*sigset)(unsafe.Pointer(&_g_.m.sigmask))
+	sigprocmask(_SIG_SETMASK, smask, nil)
 
 	signalstack(nil)
 }

src/runtime/os_darwin.go

@@ -24,7 +24,7 @@ func mach_thread_self() uint32
 func sysctl(mib *uint32, miblen uint32, out *byte, size *uintptr, dst *byte, ndst uintptr) int32
 
 //go:noescape
-func sigprocmask(how uint32, new, old *sigset)
+func sigprocmask(how uint32, new, old *uint32)
 
 //go:noescape
 func sigaction(mode uint32, new, old *sigactiont)

src/runtime/os_openbsd.go

@@ -18,7 +18,7 @@ func sigaction(sig int32, new, old *sigactiont)
 func sigaltstack(new, old *stackt)
 
 //go:noescape
-func sigprocmask(mode int32, new sigset) sigset
+func sigprocmask(mode int32, new uint32) uint32
 
 //go:noescape
 func sysctl(mib *uint32, miblen uint32, out *byte, size *uintptr, dst *byte, ndst uintptr) int32

src/runtime/runtime2.go

@@ -273,7 +273,7 @@ type m struct {
 	// Fields not known to debuggers.
 	procid        uint64     // for debuggers, but offset not hard-coded
 	gsignal       *g         // signal-handling g
-	sigmask       sigset     // storage for saved signal mask
+	sigmask       [4]uintptr // storage for saved signal mask
 	tls           [6]uintptr // thread-local storage (for x86 extern register)
 	mstartfn      func()
 	curg          *g       // current running goroutine