lbcd/txscript
Dave Collins b6e52fbd93 txscript: Convert to new scriptnum type.
This commit implements a new type, named scriptNum, for handling all
numeric values used in scripts and converts the code over to make use of
it.  This is being done for a few of reasons.

First, the consensus rules for handling numeric values in the scripts
require special handling with subtle semantics.  By encapsulating those
details into a type specifically dedicated to that purpose, it
simplifies the code and generally helps prevent improper usage.

Second, the new type is quite a bit more efficient than big.Ints which
are designed to be arbitrarily large and thus involve a lot of heap
allocations and additional multi-precision bookkeeping.  Because this
new type is based on an int64, it allows the numbers to be stack
allocated thereby eliminating a lot of GC and also eliminates the extra
multi-precision arithmetic bookkeeping.

The use of an int64 is possible because the consensus rules dictate that
when data is interpreted as a number, it is limited to an int32 even
though results outside of this range are allowed so long as they are not
interpreted as integers again themselves.   Thus, the maximum possible
result comes from multiplying a max int32 by itself which safely fits
into an int64 and can then still appropriately provide the serialization
of the larger number as required by consensus.

Finally, it more closely resembles the implementation used by Bitcoin
Core and thus makes is easier to compare the behavior between the two
implementations.

This commit also includes a full suite of tests with 100% coverage of
the semantics of the new type.
2015-05-01 13:15:08 -05:00
..
data txscript: Cleanup and improve opcode tests. 2015-04-28 03:19:00 -05:00
address.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
address_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
engine.go txscript: Convert to new scriptnum type. 2015-05-01 13:15:08 -05:00
engine_test.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
example_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
internal_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
log.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
log_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
opcode.go txscript: Convert to new scriptnum type. 2015-05-01 13:15:08 -05:00
opcode_test.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
reference_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
script.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
script_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
scriptbuilder.go txscript: Convert to new scriptnum type. 2015-05-01 13:15:08 -05:00
scriptbuilder_test.go txscript: Convert to new scriptnum type. 2015-05-01 13:15:08 -05:00
scriptnum.go txscript: Convert to new scriptnum type. 2015-05-01 13:15:08 -05:00
scriptnum_test.go txscript: Convert to new scriptnum type. 2015-05-01 13:15:08 -05:00
sign.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
sign_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
stack.go txscript: Convert to new scriptnum type. 2015-05-01 13:15:08 -05:00
stack_test.go txscript: Convert to new scriptnum type. 2015-05-01 13:15:08 -05:00

txscript

[Build Status] (https://travis-ci.org/btcsuite/btcd)

Package txscript implements the bitcoin transaction script language. There is a comprehensive test suite. Package txscript is licensed under the liberal ISC license.

This package has intentionally been designed so it can be used as a standalone package for any projects needing to use or validate bitcoin transaction scripts.

Bitcoin Scripts

Bitcoin provides a stack-based, FORTH-like langauge for the scripts in the bitcoin transactions. This language is not turing complete although it is still fairly powerful. A description of the language can be found at https://en.bitcoin.it/wiki/Script

Documentation

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

Full go doc style documentation for the project can be viewed online without installing this package by using the GoDoc site here.

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/txscript

Installation

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

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 txscript is licensed under the liberal ISC License.