126 lines
2.5 KiB
Go
126 lines
2.5 KiB
Go
package fifo
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import (
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"fmt"
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"io"
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"net"
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"os"
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"sync"
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"time"
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winio "github.com/Microsoft/go-winio"
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)
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// PipeBufferSize is the size of the input and output buffers for the windows
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// named pipe
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const PipeBufferSize = int32(^uint16(0))
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type winFIFO struct {
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listener net.Listener
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conn net.Conn
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connLock sync.Mutex
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}
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func (f *winFIFO) ensureConn() (net.Conn, error) {
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f.connLock.Lock()
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defer f.connLock.Unlock()
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if f.conn == nil {
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c, err := f.listener.Accept()
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if err != nil {
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return nil, err
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}
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f.conn = c
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}
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return f.conn, nil
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}
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func (f *winFIFO) Read(p []byte) (n int, err error) {
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conn, err := f.ensureConn()
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if err != nil {
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return 0, err
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}
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// If the connection is closed then we need to close the listener
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// to emulate unix fifo behavior
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n, err = conn.Read(p)
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if err == io.EOF {
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f.listener.Close()
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}
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return n, err
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}
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func (f *winFIFO) Write(p []byte) (n int, err error) {
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conn, err := f.ensureConn()
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if err != nil {
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return 0, err
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}
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// If the connection is closed then we need to close the listener
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// to emulate unix fifo behavior
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n, err = conn.Write(p)
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if err == io.EOF {
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conn.Close()
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f.listener.Close()
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}
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return n, err
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}
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func (f *winFIFO) Close() error {
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f.connLock.Lock()
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if f.conn != nil {
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f.conn.Close()
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}
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f.connLock.Unlock()
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return f.listener.Close()
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}
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// CreateAndRead creates a fifo at the given path and returns an io.ReadCloser open for it.
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// The fifo must not already exist
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func CreateAndRead(path string) (func() (io.ReadCloser, error), error) {
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l, err := winio.ListenPipe(path, &winio.PipeConfig{
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InputBufferSize: PipeBufferSize,
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OutputBufferSize: PipeBufferSize,
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})
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if err != nil {
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return nil, fmt.Errorf("failed to create fifo: %v", err)
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}
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return func() (io.ReadCloser, error) {
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return &winFIFO{
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listener: l,
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}, nil
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}, nil
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}
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func OpenReader(path string) (io.ReadCloser, error) {
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l, err := winio.ListenOnlyPipe(path, nil)
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if err != nil {
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return nil, fmt.Errorf("failed to open fifo listener: %v", err)
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}
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return &winFIFO{listener: l}, nil
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}
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// OpenWriter opens a fifo that already exists and returns an io.WriteCloser for it
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func OpenWriter(path string) (io.WriteCloser, error) {
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return winio.DialPipe(path, nil)
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}
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// Remove a fifo that already exists at a given path
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func Remove(path string) error {
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dur := 500 * time.Millisecond
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conn, err := winio.DialPipe(path, &dur)
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if err == nil {
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return conn.Close()
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}
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os.Remove(path)
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return nil
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}
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func IsClosedErr(err error) bool {
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return err == winio.ErrFileClosed
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}
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