From 79b1169a9ff0b54ddf3b520a70a79c78ba5c988d Mon Sep 17 00:00:00 2001 From: Determinant Date: Mon, 21 Oct 2019 14:47:51 -0400 Subject: customize Blockchain code --- core/tx_journal.go | 180 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 180 insertions(+) create mode 100644 core/tx_journal.go (limited to 'core/tx_journal.go') diff --git a/core/tx_journal.go b/core/tx_journal.go new file mode 100644 index 0000000..dfd8dab --- /dev/null +++ b/core/tx_journal.go @@ -0,0 +1,180 @@ +// Copyright 2017 The go-ethereum Authors +// This file is part of the go-ethereum library. +// +// The go-ethereum library is free software: you can redistribute it and/or modify +// it under the terms of the GNU Lesser General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// The go-ethereum library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public License +// along with the go-ethereum library. If not, see . + +package core + +import ( + "errors" + "io" + "os" + + "github.com/ava-labs/go-ethereum/common" + "github.com/ava-labs/go-ethereum/core/types" + "github.com/ava-labs/go-ethereum/log" + "github.com/ava-labs/go-ethereum/rlp" +) + +// errNoActiveJournal is returned if a transaction is attempted to be inserted +// into the journal, but no such file is currently open. +var errNoActiveJournal = errors.New("no active journal") + +// devNull is a WriteCloser that just discards anything written into it. Its +// goal is to allow the transaction journal to write into a fake journal when +// loading transactions on startup without printing warnings due to no file +// being read for write. +type devNull struct{} + +func (*devNull) Write(p []byte) (n int, err error) { return len(p), nil } +func (*devNull) Close() error { return nil } + +// txJournal is a rotating log of transactions with the aim of storing locally +// created transactions to allow non-executed ones to survive node restarts. +type txJournal struct { + path string // Filesystem path to store the transactions at + writer io.WriteCloser // Output stream to write new transactions into +} + +// newTxJournal creates a new transaction journal to +func newTxJournal(path string) *txJournal { + return &txJournal{ + path: path, + } +} + +// load parses a transaction journal dump from disk, loading its contents into +// the specified pool. +func (journal *txJournal) load(add func([]*types.Transaction) []error) error { + // Skip the parsing if the journal file doesn't exist at all + if _, err := os.Stat(journal.path); os.IsNotExist(err) { + return nil + } + // Open the journal for loading any past transactions + input, err := os.Open(journal.path) + if err != nil { + return err + } + defer input.Close() + + // Temporarily discard any journal additions (don't double add on load) + journal.writer = new(devNull) + defer func() { journal.writer = nil }() + + // Inject all transactions from the journal into the pool + stream := rlp.NewStream(input, 0) + total, dropped := 0, 0 + + // Create a method to load a limited batch of transactions and bump the + // appropriate progress counters. Then use this method to load all the + // journaled transactions in small-ish batches. + loadBatch := func(txs types.Transactions) { + for _, err := range add(txs) { + if err != nil { + log.Debug("Failed to add journaled transaction", "err", err) + dropped++ + } + } + } + var ( + failure error + batch types.Transactions + ) + for { + // Parse the next transaction and terminate on error + tx := new(types.Transaction) + if err = stream.Decode(tx); err != nil { + if err != io.EOF { + failure = err + } + if batch.Len() > 0 { + loadBatch(batch) + } + break + } + // New transaction parsed, queue up for later, import if threshold is reached + total++ + + if batch = append(batch, tx); batch.Len() > 1024 { + loadBatch(batch) + batch = batch[:0] + } + } + log.Info("Loaded local transaction journal", "transactions", total, "dropped", dropped) + + return failure +} + +// insert adds the specified transaction to the local disk journal. +func (journal *txJournal) insert(tx *types.Transaction) error { + if journal.writer == nil { + return errNoActiveJournal + } + if err := rlp.Encode(journal.writer, tx); err != nil { + return err + } + return nil +} + +// rotate regenerates the transaction journal based on the current contents of +// the transaction pool. +func (journal *txJournal) rotate(all map[common.Address]types.Transactions) error { + // Close the current journal (if any is open) + if journal.writer != nil { + if err := journal.writer.Close(); err != nil { + return err + } + journal.writer = nil + } + // Generate a new journal with the contents of the current pool + replacement, err := os.OpenFile(journal.path+".new", os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0755) + if err != nil { + return err + } + journaled := 0 + for _, txs := range all { + for _, tx := range txs { + if err = rlp.Encode(replacement, tx); err != nil { + replacement.Close() + return err + } + } + journaled += len(txs) + } + replacement.Close() + + // Replace the live journal with the newly generated one + if err = os.Rename(journal.path+".new", journal.path); err != nil { + return err + } + sink, err := os.OpenFile(journal.path, os.O_WRONLY|os.O_APPEND, 0755) + if err != nil { + return err + } + journal.writer = sink + log.Info("Regenerated local transaction journal", "transactions", journaled, "accounts", len(all)) + + return nil +} + +// close flushes the transaction journal contents to disk and closes the file. +func (journal *txJournal) close() error { + var err error + + if journal.writer != nil { + err = journal.writer.Close() + journal.writer = nil + } + return err +} -- cgit v1.2.3