re PR go/48312 (http, rpc, websocket tests hang on Solaris 2/x86)

	PR go/48312
Fix fd_select.go for changes in FD handling.

We have to wake up the goroutine waiting in select each time
we change the set of descriptors we are waiting for, unlike
epoll.

From-SVN: r171623

libgo/go/net/fd.go

@@ -122,9 +122,13 @@ func (s *pollServer) AddFD(fd *netFD, mode int) {
 		doWakeup = true
 	}
 
-	if err := s.poll.AddFD(intfd, mode, false); err != nil {
+	wake, err := s.poll.AddFD(intfd, mode, false)
+	if err != nil {
 		panic("pollServer AddFD " + err.String())
 	}
+	if wake {
+		doWakeup = true
+	}
 
 	s.Unlock()
 

libgo/go/net/fd_linux.go

@@ -47,7 +47,7 @@ func newpollster() (p *pollster, err os.Error) {
 	return p, nil
 }
 
-func (p *pollster) AddFD(fd int, mode int, repeat bool) os.Error {
+func (p *pollster) AddFD(fd int, mode int, repeat bool) (bool, os.Error) {
 	// pollServer is locked.
 
 	var already bool
@@ -69,10 +69,10 @@ func (p *pollster) AddFD(fd int, mode int, repeat bool) os.Error {
 		op = syscall.EPOLL_CTL_ADD
 	}
 	if e := syscall.EpollCtl(p.epfd, op, fd, &p.ctlEvent); e != 0 {
-		return os.NewSyscallError("epoll_ctl", e)
+		return false, os.NewSyscallError("epoll_ctl", e)
 	}
 	p.events[fd] = p.ctlEvent.Events
-	return nil
+	return false, nil
 }
 
 func (p *pollster) StopWaiting(fd int, bits uint) {

libgo/go/net/fd_select.go

@@ -32,7 +32,9 @@ func newpollster() (p *pollster, err os.Error) {
 	return p, nil
 }
 
-func (p *pollster) AddFD(fd int, mode int, repeat bool) os.Error {
+func (p *pollster) AddFD(fd int, mode int, repeat bool) (bool, os.Error) {
+	// pollServer is locked.
+
 	if mode == 'r' {
 		syscall.FDSet(fd, p.readFds)
 	} else {
@@ -47,10 +49,12 @@ func (p *pollster) AddFD(fd int, mode int, repeat bool) os.Error {
 		p.maxFd = fd
 	}
 
-	return nil
+	return true, nil
 }
 
 func (p *pollster) DelFD(fd int, mode int) {
+	// pollServer is locked.
+
 	if mode == 'r' {
 		if !syscall.FDIsSet(fd, p.readFds) {
 			print("Select unexpected fd=", fd, " for read\n")
@@ -71,7 +75,7 @@ func (p *pollster) DelFD(fd int, mode int) {
 	// We don't worry about maxFd here.
 }
 
-func (p *pollster) WaitFD(nsec int64) (fd int, mode int, err os.Error) {
+func (p *pollster) WaitFD(s *pollServer, nsec int64) (fd int, mode int, err os.Error) {
 	if p.nReady == 0 {
 		var timeout *syscall.Timeval
 		var tv syscall.Timeval
@@ -89,7 +93,10 @@ func (p *pollster) WaitFD(nsec int64) (fd int, mode int, err os.Error) {
 			tmpReadFds = *p.readFds
 			tmpWriteFds = *p.writeFds
 
+			s.Unlock()
 			n, e = syscall.Select(p.maxFd + 1, &tmpReadFds, &tmpWriteFds, nil, timeout)
+			s.Lock()
+
 			if e != syscall.EINTR {
 				break
 			}

libgo/go/net/newpollserver.go

@@ -31,7 +31,7 @@ func newPollServer() (s *pollServer, err os.Error) {
 	if s.poll, err = newpollster(); err != nil {
 		goto Error
 	}
-	if err = s.poll.AddFD(s.pr.Fd(), 'r', true); err != nil {
+	if _, err = s.poll.AddFD(s.pr.Fd(), 'r', true); err != nil {
 		s.poll.Close()
 		goto Error
 	}

libgo/go/net/newpollserver_rtems.go

@@ -68,7 +68,7 @@ func newPollServer() (s *pollServer, err os.Error) {
 	if s.poll, err = newpollster(); err != nil {
 		goto Error
 	}
-	if err = s.poll.AddFD(s.pr.Fd(), 'r', true); err != nil {
+	if _, err = s.poll.AddFD(s.pr.Fd(), 'r', true); err != nil {
 		s.poll.Close()
 		goto Error
 	}