Golang Uint256.Equal Examples

Example #1

File: fetchtx.go Project: piotrnar/gocoin

// Download raw transaction from a web server (try one after another)
func GetTxFromWeb(txid *btc.Uint256) (raw []byte) {
	raw = GetTxFromExplorer(txid)
	if raw != nil && txid.Equal(btc.NewSha2Hash(raw)) {
		println("GetTxFromExplorer - OK")
		return
	}

	raw = GetTxFromWebBTC(txid)
	if raw != nil && txid.Equal(btc.NewSha2Hash(raw)) {
		println("GetTxFromWebBTC - OK")
		return
	}

	raw = GetTxFromBlockrIo(txid)
	if raw != nil && txid.Equal(btc.NewSha2Hash(raw)) {
		println("GetTxFromBlockrIo - OK")
		return
	}

	raw = GetTxFromBlockchainInfo(txid)
	if raw != nil && txid.Equal(btc.NewSha2Hash(raw)) {
		println("GetTxFromBlockchainInfo - OK")
		return
	}

	return
}

Example #2

File: bootdat_qt.go Project: liudch/gocoin

func main() {
	if len(os.Args) < 2 {
		fmt.Println("Specify a path to folder containig blockchain.dat and blockchain.new")
		fmt.Println("Output bootstrap.dat file will be written in the current folder.")
		return
	}

	blks := chain.NewBlockDB(os.Args[1])
	if blks == nil {
		return
	}
	fmt.Println("Loading block index...")
	bidx = make(map[[32]byte]*chain.BlockTreeNode, 300e3)
	blks.LoadBlockIndex(nil, walk)

	var tail, nd *chain.BlockTreeNode
	var genesis_block_hash *btc.Uint256
	for _, v := range bidx {
		if v == tail {
			// skip root block (should be only one)
			continue
		}

		par_hash := btc.NewUint256(v.BlockHeader[4:36])
		par, ok := bidx[par_hash.Hash]
		if !ok {
			genesis_block_hash = par_hash
		} else {
			v.Parent = par
			if tail == nil || v.Height > tail.Height {
				tail = v
			}
		}
	}

	if genesis_block_hash == nil {
		println("genesis_block_hash not found")
		return
	}

	var magic []byte

	gen_bin, _ := hex.DecodeString(GenesisBitcoin)
	tmp := btc.NewSha2Hash(gen_bin[:80])
	if genesis_block_hash.Equal(tmp) {
		println("Bitcoin genesis block")
		magic = []byte{0xF9, 0xBE, 0xB4, 0xD9}
	}

	if magic == nil {
		gen_bin, _ := hex.DecodeString(GenesisTestnet)
		tmp = btc.NewSha2Hash(gen_bin[:80])
		if genesis_block_hash.Equal(tmp) {
			println("Testnet3 genesis block")
			magic = []byte{0x0B, 0x11, 0x09, 0x07}
		}
	}

	if magic == nil {
		println("Unknow genesis block", genesis_block_hash.String())
		println("Aborting since cannot figure out the magic bytes")
		return
	}

	var total_data, curr_data int64

	for nd = tail; nd.Parent != nil; {
		nd.Parent.Childs = []*chain.BlockTreeNode{nd}
		total_data += int64(nd.BlockSize)
		nd = nd.Parent
	}
	fmt.Println("Writting bootstrap.dat, height", tail.Height, "  magic", hex.EncodeToString(magic))
	f, _ := os.Create("bootstrap.dat")
	f.Write(magic)
	binary.Write(f, binary.LittleEndian, uint32(len(gen_bin)))
	f.Write(gen_bin)
	for {
		bl, _, _ := blks.BlockGet(nd.BlockHash)
		f.Write(magic)
		binary.Write(f, binary.LittleEndian, uint32(len(bl)))
		f.Write(bl)
		curr_data += int64(nd.BlockSize)
		if (nd.Height & 0xfff) == 0 {
			fmt.Printf("\r%.1f%%...", 100*float64(curr_data)/float64(total_data))
		}
		if len(nd.Childs) == 0 {
			break
		}
		nd = nd.Childs[0]
	}
	fmt.Println("\rDone           ")
}