2018-12-05 21:13:29 +08:00
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package dns
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import (
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"context"
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2020-02-09 17:02:48 +08:00
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"github.com/Dreamacro/clash/component/dialer"
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2018-12-05 21:13:29 +08:00
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D "github.com/miekg/dns"
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)
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2019-06-28 12:29:08 +08:00
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type client struct {
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*D.Client
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2018-12-05 21:13:29 +08:00
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Address string
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}
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2019-06-28 12:29:08 +08:00
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func (c *client) Exchange(m *D.Msg) (msg *D.Msg, err error) {
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return c.ExchangeContext(context.Background(), m)
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2018-12-05 21:13:29 +08:00
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}
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2019-06-28 12:29:08 +08:00
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func (c *client) ExchangeContext(ctx context.Context, m *D.Msg) (msg *D.Msg, err error) {
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2020-02-09 17:02:48 +08:00
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c.Client.Dialer = dialer.Dialer()
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2020-02-14 16:36:20 +08:00
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// miekg/dns ExchangeContext doesn't respond to context cancel.
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// this is a workaround
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type result struct {
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msg *D.Msg
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err error
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}
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ch := make(chan result, 1)
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go func() {
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msg, _, err := c.Client.ExchangeContext(ctx, m, c.Address)
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ch <- result{msg, err}
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}()
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select {
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case <-ctx.Done():
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return nil, ctx.Err()
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case ret := <-ch:
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return ret.msg, ret.err
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}
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2018-12-05 21:13:29 +08:00
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}
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