44 lines
828 B
Go
44 lines
828 B
Go
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package main
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import (
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"github.com/conformal/btcwire"
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"log"
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"net"
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"sync"
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)
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func GetSeedsFromDNS(dnsSeeds []string) []string {
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wait := sync.WaitGroup{}
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results := make(chan []net.IP)
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for _, address := range dnsSeeds {
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wait.Add(1)
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go func() {
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defer wait.Done()
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ips, err := net.LookupIP(address)
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if err != nil {
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log.Printf("Failed to resolve %s: %v", address, err)
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return
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}
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results <- ips
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}()
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}
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go func() {
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wait.Wait()
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close(results)
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}()
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seeds := []string{}
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for ips := range results {
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for _, ip := range ips {
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seeds = append(seeds, net.JoinHostPort(ip.String(), btcwire.MainPort))
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}
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}
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log.Printf("Resolved %d seed nodes from %d DNS seeds.", len(seeds), len(dnsSeeds))
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// Note that this will likely include duplicate seeds. The crawler deduplicates them.
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return seeds
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}
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