github.com/oweisse/u-root@v0.0.0-20181109060735-d005ad25fef1/cmds/elvish/sys/fdset_notfreebsd.go (about)

     1  // +build !freebsd,!windows,!plan9
     2  
     3  package sys
     4  
     5  import (
     6  	"unsafe"
     7  
     8  	"golang.org/x/sys/unix"
     9  )
    10  
    11  var nFdBits = uint(8 * unsafe.Sizeof(unix.FdSet{}.Bits[0]))
    12  
    13  type FdSet unix.FdSet
    14  
    15  func (fs *FdSet) s() *unix.FdSet {
    16  	return (*unix.FdSet)(fs)
    17  }
    18  
    19  func NewFdSet(fds ...int) *FdSet {
    20  	fs := &FdSet{}
    21  	fs.Set(fds...)
    22  	return fs
    23  }
    24  
    25  func (fs *FdSet) Clear(fds ...int) {
    26  	for _, fd := range fds {
    27  		u := uint(fd)
    28  		fs.Bits[u/nFdBits] &= ^(1 << (u % nFdBits))
    29  	}
    30  }
    31  
    32  func (fs *FdSet) IsSet(fd int) bool {
    33  	u := uint(fd)
    34  	return fs.Bits[u/nFdBits]&(1<<(u%nFdBits)) != 0
    35  }
    36  
    37  func (fs *FdSet) Set(fds ...int) {
    38  	for _, fd := range fds {
    39  		u := uint(fd)
    40  		fs.Bits[u/nFdBits] |= 1 << (u % nFdBits)
    41  	}
    42  }
    43  
    44  func (fs *FdSet) Zero() {
    45  	*fs = FdSet{}
    46  }