| // 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. |
| |
| // Waiting for FDs via kqueue/kevent. |
| |
| package net |
| |
| import ( |
| "os" |
| "syscall" |
| ) |
| |
| type pollster struct { |
| kq int |
| eventbuf [10]syscall.Kevent_t |
| events []syscall.Kevent_t |
| } |
| |
| func newpollster() (p *pollster, err os.Error) { |
| p = new(pollster) |
| var e int |
| if p.kq, e = syscall.Kqueue(); e != 0 { |
| return nil, os.NewSyscallError("kqueue", e) |
| } |
| p.events = p.eventbuf[0:0] |
| return p, nil |
| } |
| |
| func (p *pollster) AddFD(fd int, mode int, repeat bool) os.Error { |
| var kmode int |
| if mode == 'r' { |
| kmode = syscall.EVFILT_READ |
| } else { |
| kmode = syscall.EVFILT_WRITE |
| } |
| var events [1]syscall.Kevent_t |
| ev := &events[0] |
| // EV_ADD - add event to kqueue list |
| // EV_ONESHOT - delete the event the first time it triggers |
| flags := syscall.EV_ADD |
| if !repeat { |
| flags |= syscall.EV_ONESHOT |
| } |
| syscall.SetKevent(ev, fd, kmode, flags) |
| |
| n, e := syscall.Kevent(p.kq, events[:], nil, nil) |
| if e != 0 { |
| return os.NewSyscallError("kevent", e) |
| } |
| if n != 1 || (ev.Flags&syscall.EV_ERROR) == 0 || int(ev.Ident) != fd || int(ev.Filter) != kmode { |
| return os.NewSyscallError("kqueue phase error", e) |
| } |
| if ev.Data != 0 { |
| return os.Errno(int(ev.Data)) |
| } |
| return nil |
| } |
| |
| func (p *pollster) DelFD(fd int, mode int) { |
| var kmode int |
| if mode == 'r' { |
| kmode = syscall.EVFILT_READ |
| } else { |
| kmode = syscall.EVFILT_WRITE |
| } |
| var events [1]syscall.Kevent_t |
| ev := &events[0] |
| // EV_DELETE - delete event from kqueue list |
| syscall.SetKevent(ev, fd, kmode, syscall.EV_DELETE) |
| syscall.Kevent(p.kq, events[:], nil, nil) |
| } |
| |
| func (p *pollster) WaitFD(nsec int64) (fd int, mode int, err os.Error) { |
| var t *syscall.Timespec |
| for len(p.events) == 0 { |
| if nsec > 0 { |
| if t == nil { |
| t = new(syscall.Timespec) |
| } |
| *t = syscall.NsecToTimespec(nsec) |
| } |
| nn, e := syscall.Kevent(p.kq, nil, p.eventbuf[:], t) |
| if e != 0 { |
| if e == syscall.EINTR { |
| continue |
| } |
| return -1, 0, os.NewSyscallError("kevent", e) |
| } |
| if nn == 0 { |
| return -1, 0, nil |
| } |
| p.events = p.eventbuf[0:nn] |
| } |
| ev := &p.events[0] |
| p.events = p.events[1:] |
| fd = int(ev.Ident) |
| if ev.Filter == syscall.EVFILT_READ { |
| mode = 'r' |
| } else { |
| mode = 'w' |
| } |
| return fd, mode, nil |
| } |
| |
| func (p *pollster) Close() os.Error { return os.NewSyscallError("close", syscall.Close(p.kq)) } |