github.com/tidwall/go@v0.0.0-20170415222209-6694a6888b7d/src/internal/poll/fd_poll_nacl.go (about)

     1  // Copyright 2013 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package poll
     6  
     7  import (
     8  	"syscall"
     9  	"time"
    10  )
    11  
    12  type pollDesc struct {
    13  	fd      *FD
    14  	closing bool
    15  }
    16  
    17  func (pd *pollDesc) init(fd *FD) error { pd.fd = fd; return nil }
    18  
    19  func (pd *pollDesc) close() {}
    20  
    21  func (pd *pollDesc) evict() {
    22  	pd.closing = true
    23  	if pd.fd != nil {
    24  		syscall.StopIO(pd.fd.Sysfd)
    25  	}
    26  }
    27  
    28  func (pd *pollDesc) prepare(mode int) error {
    29  	if pd.closing {
    30  		return ErrClosing
    31  	}
    32  	return nil
    33  }
    34  
    35  func (pd *pollDesc) prepareRead() error { return pd.prepare('r') }
    36  
    37  func (pd *pollDesc) prepareWrite() error { return pd.prepare('w') }
    38  
    39  func (pd *pollDesc) wait(mode int) error {
    40  	if pd.closing {
    41  		return ErrClosing
    42  	}
    43  	return ErrTimeout
    44  }
    45  
    46  func (pd *pollDesc) waitRead() error { return pd.wait('r') }
    47  
    48  func (pd *pollDesc) waitWrite() error { return pd.wait('w') }
    49  
    50  func (pd *pollDesc) waitCanceled(mode int) {}
    51  
    52  // SetDeadline sets the read and write deadlines associated with fd.
    53  func (fd *FD) SetDeadline(t time.Time) error {
    54  	return setDeadlineImpl(fd, t, 'r'+'w')
    55  }
    56  
    57  // SetReadDeadline sets the read deadline associated with fd.
    58  func (fd *FD) SetReadDeadline(t time.Time) error {
    59  	return setDeadlineImpl(fd, t, 'r')
    60  }
    61  
    62  // SetWriteDeadline sets the write deadline associated with fd.
    63  func (fd *FD) SetWriteDeadline(t time.Time) error {
    64  	return setDeadlineImpl(fd, t, 'w')
    65  }
    66  
    67  func setDeadlineImpl(fd *FD, t time.Time, mode int) error {
    68  	d := t.UnixNano()
    69  	if t.IsZero() {
    70  		d = 0
    71  	}
    72  	if err := fd.incref(); err != nil {
    73  		return err
    74  	}
    75  	switch mode {
    76  	case 'r':
    77  		syscall.SetReadDeadline(fd.Sysfd, d)
    78  	case 'w':
    79  		syscall.SetWriteDeadline(fd.Sysfd, d)
    80  	case 'r' + 'w':
    81  		syscall.SetReadDeadline(fd.Sysfd, d)
    82  		syscall.SetWriteDeadline(fd.Sysfd, d)
    83  	}
    84  	fd.decref()
    85  	return nil
    86  }
    87  
    88  // PollDescriptor returns the descriptor being used by the poller,
    89  // or ^uintptr(0) if there isn't one. This is only used for testing.
    90  func PollDescriptor() uintptr {
    91  	return ^uintptr(0)
    92  }