lbcd/blockchain
Dave Collins 0280fa0264 Convert block heights to int32.
This commit converts all block height references to int32 instead of
int64.  The current target block production rate is 10 mins per block
which means it will take roughly 40,800 years to reach the maximum
height an int32 affords.  Even if the target rate were lowered to one
block per minute, it would still take roughly another 4,080 years to
reach the maximum.

In the mean time, there is no reason to use a larger type which results
in higher memory and disk space usage.  However, for now, in order to
avoid having to reserialize a bunch of database information, the heights
are still serialized to the database as 8-byte uint64s.

This is being mainly being done in preparation for further upcoming
infrastructure changes which will use the smaller and more efficient
4-byte serialization in the database as well.
2015-08-11 11:13:17 -05:00
..
testdata Import btcchain repo into blockchain directory. 2015-01-30 15:49:59 -06:00
accept.go Convert block heights to int32. 2015-08-11 11:13:17 -05:00
bench_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
blocklocator.go Convert block heights to int32. 2015-08-11 11:13:17 -05:00
chain.go Convert block heights to int32. 2015-08-11 11:13:17 -05:00
chain_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
checkpoints.go Convert block heights to int32. 2015-08-11 11:13:17 -05:00
common_test.go Convert block heights to int32. 2015-08-11 11:13:17 -05:00
difficulty.go Convert block heights to int32. 2015-08-11 11:13:17 -05:00
difficulty_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
doc.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
error.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
error_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
example_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
internal_test.go Convert block heights to int32. 2015-08-11 11:13:17 -05:00
log.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
mediantime.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
mediantime_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
merkle.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
merkle_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
notifications.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
process.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
README.md Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
reorganization_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
scriptval.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
scriptval_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
timesorter.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
timesorter_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
txlookup.go Convert block heights to int32. 2015-08-11 11:13:17 -05:00
validate.go Convert block heights to int32. 2015-08-11 11:13:17 -05:00
validate_test.go Convert block heights to int32. 2015-08-11 11:13:17 -05:00

blockchain

[Build Status] (https://travis-ci.org/btcsuite/btcd) ![ISC License] (http://img.shields.io/badge/license-ISC-blue.svg)

Package blockchain implements bitcoin block handling and chain selection rules. The test coverage is currently only around 60%, but will be increasing over time. See test_coverage.txt for the gocov coverage report. Alternatively, if you are running a POSIX OS, you can run the cov_report.sh script for a real-time report. Package blockchain is licensed under the liberal ISC license.

There is an associated blog post about the release of this package here.

This package has intentionally been designed so it can be used as a standalone package for any projects needing to handle processing of blocks into the bitcoin block chain.

Documentation

[GoDoc] (http://godoc.org/github.com/btcsuite/btcd/blockchain)

Full go doc style documentation for the project can be viewed online without installing this package by using the GoDoc site here: http://godoc.org/github.com/btcsuite/btcd/blockchain

You can also view the documentation locally once the package is installed with the godoc tool by running godoc -http=":6060" and pointing your browser to http://localhost:6060/pkg/github.com/btcsuite/btcd/blockchain

Installation

$ go get github.com/btcsuite/btcd/blockchain

Bitcoin Chain Processing Overview

Before a block is allowed into the block chain, it must go through an intensive series of validation rules. The following list serves as a general outline of those rules to provide some intuition into what is going on under the hood, but is by no means exhaustive:

  • Reject duplicate blocks
  • Perform a series of sanity checks on the block and its transactions such as verifying proof of work, timestamps, number and character of transactions, transaction amounts, script complexity, and merkle root calculations
  • Compare the block against predetermined checkpoints for expected timestamps and difficulty based on elapsed time since the checkpoint
  • Save the most recent orphan blocks for a limited time in case their parent blocks become available
  • Stop processing if the block is an orphan as the rest of the processing depends on the block's position within the block chain
  • Perform a series of more thorough checks that depend on the block's position within the block chain such as verifying block difficulties adhere to difficulty retarget rules, timestamps are after the median of the last several blocks, all transactions are finalized, checkpoint blocks match, and block versions are in line with the previous blocks
  • Determine how the block fits into the chain and perform different actions accordingly in order to ensure any side chains which have higher difficulty than the main chain become the new main chain
  • When a block is being connected to the main chain (either through reorganization of a side chain to the main chain or just extending the main chain), perform further checks on the block's transactions such as verifying transaction duplicates, script complexity for the combination of connected scripts, coinbase maturity, double spends, and connected transaction values
  • Run the transaction scripts to verify the spender is allowed to spend the coins
  • Insert the block into the block database

Examples

GPG Verification Key

All official release tags are signed by Conformal so users can ensure the code has not been tampered with and is coming from the btcsuite developers. To verify the signature perform the following:

  • Download the public key from the Conformal website at https://opensource.conformal.com/GIT-GPG-KEY-conformal.txt

  • Import the public key into your GPG keyring:

    gpg --import GIT-GPG-KEY-conformal.txt
    
  • Verify the release tag with the following command where TAG_NAME is a placeholder for the specific tag:

    git tag -v TAG_NAME
    

License

Package blockchain is licensed under the copyfree ISC License.