73 lines
1.5 KiB
Go
73 lines
1.5 KiB
Go
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package packer
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import (
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"context"
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"errors"
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)
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type Server struct {
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ctx context.Context
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newConns chan *Conn
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data []byte
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dataReady chan struct{}
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}
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func (s *Server) Accept() (*Conn, error) {
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select {
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case <-s.ctx.Done():
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return nil, errors.New("TODO: ErrClosed")
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case conn := <-s.newConns:
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return conn, nil
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}
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}
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// Read packs transforms local responses into wrapped data for the tunnel
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func (s *Server) Read(b []byte) (int, error) {
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select {
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case <-s.ctx.Done():
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return 0, errors.New("TODO: EOF / ErrClosed")
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case <-s.dataReady:
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if 0 == len(s.data) {
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return s.Read(b)
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}
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return s.read(b)
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}
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}
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func (s *Server) read(b []byte) (int, error) {
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// TODO mutex data while reading, against writing?
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c := len(b) // capacity
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a := len(s.data) // available
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n := c
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// see if the available data is smaller than the receiving buffer
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if a < c {
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n = a
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}
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// copy available data up to capacity
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for i := 0; i < n; i++ {
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b[i] = s.data[i]
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}
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// shrink the data slice by amount read
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s.data = s.data[n:]
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// if there's data left over, flag as ready to read again
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// otherwise... flag as ready to write?
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if len(b) > 0 {
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s.dataReady <- struct{}{}
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} else {
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//p.writeReady <- struct{}{}
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}
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// Note a read error should not be possible here
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// as all traffic (including errors) can be wrapped
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return n, nil
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}
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// Close (TODO) should politely close all connections, if possible (set Read() to io.EOF, or use ErrClosed?)
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func (s *Server) Close() error {
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return errors.New("not implemented")
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}
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