Go 1.22 is introducing a change to the way the range statement works
that is not entirely backward compatible. In particular, the loop
variable is changing from one instance per loop to one instance per
iteration.
The existing semantics are well known and in order to ensure correct
behavior and avoid potential races that would otherwise result, the
current code typically opts for using ranges with an index and creating
a local that points into the array when the range variable needs to be
used as a pointer.
In addition, there are a few remaining cases that use the common
alternative approach of capturing the range variable through self
assignment.
Both approaches will work correctly when compiled with Go 1.22 as well
as older version of Go so long as the module versions are not bumped.
However, once the modules are updated to allow support of all features
introduced by go 1.22, the second approach of capturing the range
variable would no longer be needed and as a result would very likely
need to be removed to avoid vet/linter issues. Unfortunately, the
consequence of that change would mean building the code with older
versions of Go would start to produce incorrect code.
The first approach of using a range index that is predominantly used
throughout the code does not have that potential pitfall as it works
equally well for all of the aforementioned cases.
Thus, in order to avoid any potential issues before they ever even have
a chance to arise, this updates the few remaining instances of the
second approach to the first one or to otherwise rework the code to
avoid the need altogether.
This updates several of the tests in the script_test.go file to be more
consistent with the format used throughout the vast majority of the
other tests in the package.
The following is an overview of the changes:
- Use more compact format for the test definition tables
- Update the tests to make use of the short form script parsing logic
rather than manually defining byte slices
- Move the logic for testing various canonical integer and data pushes
into their respective test funcs
- Add names to the individual test conditions
- Update test failure output to be more consistent
This adds the ability for the short form script parsing to handle
different script versions and updates all of the tests to use the
version 0 function appropriately.
This adds explicit test cases for the consensus-specific
isAnyKindOfScriptHash method of the engine instead of using the script
class tests which are only intended for use by standardness code
This adds explicit test cases for the consensus-specific
IsPayToScriptHash func instead of using the script class tests which are
only intended for use by standardness code.
This removes PushedData along with its associated test and benchmark
from txscript since it is no longer used by anything and hasn't been for
quite some time due to the introduction of the zero allocation script
tokenizer which allows it to be done by callers more efficiently.
This moves the GenerateSSGenVotes method to script.go since it is used
in consensus code and therefore should not be in standard.go which is
only intended for standardness code.
It also moves the associated test to script_test.go to match and does
some other misc cleanup such as improving the comments and tests for
consistency.
This moves the GenerateSSGenBlockRef method to script.go since it is
used in consensus code and therefore should not be in standard.go which
is only intended for standardness code.
It also moves the associated test to script_test.go to match and does
some other misc cleanup such as improving the comments and tests for
consistency.
This is based on https://proposals.decred.org/proposals/c96290a but was
modified in order to deal with realities that were unknown at the time
of the specification draft.
It is large and could not really be broken apart due to the pervasive
use of the isTreasuryEnabled flag. It was primarily authored by
* Marco Peereboom <marco@peereboom.us>
* Dave Collins <davec@conformal.com>
* Matheus Degiovani <opensource@matheusd.com>
With additional contributions from
* Donald Adu-Poku <donald.adu@gmail.com>
* Jamie Holdstock <jholdstock@decred.org>
Major changes:
* Add decentralized treasury agenda, as specified in DCP0006, to all supported
nets.
* Add functions to determine if the decentralized treasury agenda is active at
given block.
* Add new opcode OP_TADD that is a nop in txscript but is used to tag scripts
that credit the treasury account. This opcode is overloaded for treasurybase
and for normal transactions.
* Add new opcode OP_TSPEND that is a nop in txscript but is used to tag scripts
that debit the treasury account.
* Add new opcode OP_TGEN that is a nop in txscript but is used to tag P2PKH and
P2SH outputs in a TSpend transaction.
* Add functions that detect if a transaction is a valid TAdd, TSpend
or treasurybase transaction.
* Add error codes that return specific treasurybase/TAdd/TSpend consensus
violations.
* Modify countSpentOutputs to deal with treasury opcodes accordingly.
* Modify indexBlock to skip treasury transactions that do not have inputs.
* Add IsTreasuryEnabled call to ChainQueryer interface.
* Add treasury logger for debugging and logging the decentralized treasury
subsystem.
* Add IsTreasuryActive flag to BlockConnectedNtfnsData and
BlockDisconnectedNtfnsData.
* Modify OP_SSGEN to allow an optional output that contains votes for a TSpend
transaction hash.
* Add function that returns TSpend votes from an SSGen transaction.
* Modify CalcStakeVoteSubsidy so that treasurybase, unlike coinbase, is always
awarded the full percentage of the assigned block reward.
* Add helper functions to do all TSpend math so that callers don't roll their
own.
* Modify IsCoinBaseTx to not mistake a TSpend transaction as a coinbase.
* Add checkTreasuryBase function that verifies that a treasurybase is properly
constructed and pays the right amount to the treasury account.
* Add functions to calculate treasury balance for the provided block hash/node.
* Add function that verifies if a TSpend has a valid signature.
* Add functions to determine if a TSpend is not overspending.
* Add function to determine if a TSpend has been mined on the provided chain.
* Add functions that count and verifies treasury spend votes.
* Modify connectTransaction and disconnectTransactions to deal with the various
treasury transactions.
* Split CheckTransactionSanity in two functions
checkTransactionSanityContextFree and checkTransactionSanityContextual. This
is done in order to keep the decentralized treasury, which is always
contextual, from infecting the context free checks.
* Modify checkTransactionSanityContextual to recognize and verify treasury
transactions.
* Modify CheckTransactionSanity to deal with treasury transactions.
* Split checkBlockSanity in two functions checkBlockSanityContextFree and
checkBlockSanityContextual. This is done in order to keep the decentralized
treasury, which is always contextual, from infecting the context free checks.
* Modify checkBlockSanityContextual to enforce treasurybase and TAdd consensus
checks.
* Modify checkBlockPositional by unindenting it and adding TSpend consensus
enforcement.
* Modify checkCoinbaseUniqueHeightWithAddress to deal with the removal of the
project subsidy from output 0.
* Add checkCoinbaseUniqueHeightWithTreasuryBase that verifies coinbase and
treasurybase in the provided block.
* Unindent checkBlockContext.
* Modify checkTicketRedeemerCommitments and checkVoteInputs to deal with
potential tspend votes.
* Modify CheckTransactionInputs to skip treasurybase transactions.
* Modify CheckTransactionInputs to deal with TSpend transactions. Ensure the
provided Pi key is valid and that the signature is valid for the transaction.
Ensure that treasury TAdd and TSpend transaction utxo can only be spent after
coinbase maturity.
* Modify CountSigOps to deal with treasury transactions.
* Modify CountP2SHSigOps to deal with treasury transactions.
* Modify getStakeTreeFees to skip treasury transactions. Modify
totalOutputs to subtract ValueIn 0 for TSpend and treasurybase transactions.
* Modify checkTransactionsAndConnect to deal with modified amounts.
* Add tspendChecks function that verifies an entire TSpend transaction
validity at the point of the provided block. It ensures a TSpend is on a TVI.
It ensures the TSpend is in the valid window. It verifies that a TSpend In
and Out amounts match. It ensures a TSpend has the ValueIn amount encoded in
the OP_RETURN in Out 0. It ensures a TSpend has not been mined before on this
chain. It ensures a TSpend has the requisite votes. It ensures a TSpend is
not overspending.
* Modify checkConnectBlock to call checkTreasuryBase and tspendChecks when
treasury agenda is active.
* Add two tables to the database. Table "treasury" records the balance as of
this block and balance changes that occurred in this block which will become
active in CoinbaseMaturity blocks. Table "tspend" records all block hashes
where a TSpend has been mined this is to detect forks and prevent a Tspend
from being mined more than once.
* Modify handleBlockchainNotification to communicate if the treasury agenda is
active and skip treasurybase transaction when needed.
* Add various Treasury parameters to chaincfg params.
* Add hardcoded Tspend signatures in dcr_tmux_simnet_setup.sh.
* Add notifytspend and stoptspend calls to the RPC server. notifytspend
notifies the mempool when a TSpend transaction arrives.
* Modify commit filters V2 to recognize TAdd and TSpend transactions. It was
possible to modify V2 instead of introducing V3 because nothing changes from
the viewpoint of the wallet and treasury opcodes are disallowed prior to
agenda activation.
* Modify AddMemPoolTransaction to skip TSpend transactions that would throw the
fee estimator off.
* Add IsTreasuryAgendaActive, OnTSpendReceived and TSpendMinedOnAncestor to
mempool.Config in order to reject/accept TSpends in the mempool.
* Modify checkPoolDoubleSpend to ignore treasurybase.
* Modify mempool.maybeAcceptTransaction to enforce treasury standardness rules.
Don't allow TSpend transactions prior to stake validation height. Skip
treasurybase and tspend transactions in the orphan test. Ensure a tspend is
in a valid window. Ensure not more than 7 TSpends are active in the mempool.
Ensure TSpend has a well-known Pi key. Ensure The provided Pi key was used to
sign the transaction. Ensure TSpend was not mined in an ancestor block.
Notify subscribers that a valid TSpend was received.
* Add standardCoinbaseOpReturn and standardTreasurybaseOpReturn to create an
OP_RETURN followed by a data push that little endian encodes the height of
the block. Then there are a number of random bytes to ensure that the
transaction hash is always random.
* Modify createCoinbaseTx to create a coinbase that is valid when treasury is
enabled or not. Additionally, alter the transaction version if treasury is
enabled.
* Add createTreasuryBaseTx that creates a standard treasurybase.
* Modify maybeInsertStakeTx to recognize treasurybase and TSpend transactions.
* Modify handleTooFewVoters to call createTreasuryBaseTx when the treasury
agenda is active. Skip copying treasurybase.
* Modify NewBlockTemplate to recognize and deal with treasury transactions.
Skip TSpend transaction if block is not a TVI. Skip TSpend transaction if it
is not in the proper window. Skip TSpend transaction if a TSpend does not
have enough yes votes. Skip TSpend transaction if it overspends the treasury
account. Skip TAdd if there are more than 20 TAdds in the block. Create
treasurybase if required. Insert valid TAdd/TSpend transactions into stake
tree.
* Add TreasuryBalance and IsTreasuryAgendaActive to rpcserver Chain interface.
* Add gettreasurybalance, sendfromtreasury and sendtotreasury calls to RPC
server.
* Add notifytspend and stopnotifytspend to RPC websocket commands.
* Add simnet miner to generate large number of blocks during rpctests without
triggering PoW difficulty increases. This is used to verify various treasury
and tspend conditions during CI/CT.
* Modify RPC voting wallet to also vote on TSpends.
* Add json tests to verify all new opcodes and corner cases in the script
engine.
* Modify isStakeOpcode to recognize treasury opcodes.
* Modify countSigOpsV0 to count TSpends.
* Modify handleStakeOutSign to deal with TSpends.
* Modify SignTxOutput to recognize TSpends.
* Add TSpendSignatureScript that signs a TSpend transaction.
* Add TreasuryAddTy and TreasurySpendTy types to the standard scripts.
* Add isTreasuryAddScript and isTreasurySpendScript functions that recognize
a form of TAdd and TSpend transactions.
* Modify ExtractPkScriptAddrs to deal with TAdd and TSpend outputs.
* Add TxVersionSeqLock = 2 and TxVersionTreasury = 3 to wire. This is
used to discriminate between treasury and non-treasury scripts.
* Rig up all functions that need the isTreasuryEnabledflag directly or
indirectly.
* Shuffle various functions around and export them when they were needed to be
called from other packages.
* Added and modified numerous tests to verify (hopefully) all corner cases that
the decentralized treasury agenda has added.
This updates the txscript package to provide support for the errors.Is
and errors.As functions introduced in Go 1.13 per the recently
documented best practices.
The following is an overview of the changes:
- Rename the ErrorCode type to ErrorKind and make it a string
- Implement the error interface on ErrorKind
- Update all error code definitions to the new type
- Remove error code string map that is no longer required
- Remove unused ErrInternal definition
- Change the error code field of the Error type to Err
- Implement Unwrap on the Error type to support unwrapping via
errors.Is/As
- Remove the IsErrorCode function since it is no longer needed due to
errors.Is
- Update IsDERSigError to cope with the changes
- Modify various comments to refer to error kinds instead of codes
- Update all test code to use the new ErrorKind directly along with
errors.Is for detecting the expect errors
- Add full test coverage to ensure the new error definitions work as
intended
- Update the doc.go errors section accordingly
This converts the test definitions for TestRemoveOpcodeByData to make
use of mustParseShortForm which improves the readability and
construction of the tests as well as makes them more consistent with the
rest of the code base.
It also cleans up the recently added stake tx tests so that they don't
exceed col 80 and sets their names to indicate they are p2pkh and p2sh
forms.
This introduces a new function named removeOpcodeByDataRaw which accepts
the raw scripts and data to remove versus requiring the parsed opcodes
to both significantly optimize it as well as make it more flexible for
working with raw scripts.
There are several places in the rest of the code that currently only
have access to the parsed opcodes, so this only introduces the function
for use in the future and deprecates the existing one.
Note that, in practice, the script will never actually contain the data
that is intended to be removed since the function is only used during
signature verification to remove the signature itself which would
require some incredibly non-standard code to create.
Thus, as an optimization, it avoids allocating a new script unless there
is actually a match that needs to be removed.
Finally, it updates the tests to use the new function.
This renames the canonicalPush function to isCanonicalPush and converts
it to accept an opcode as a byte and the associate data as a byte slice
instead of the internal parse opcode data struct in order to make it
more flexible for raw script analysis.
It also updates all callers and tests accordingly.
This converts the isAnyKindOfScriptHash function to analyze the raw
script instead of requiring far less efficient parsed opcodes thereby
significantly optimizing the function.
Since the function relies on isStakeScriptHash to identify a stake
tagged pay-to-script-hash, and is the only consumer of it, this also
converts that function to analyze the raw script and renames it to
isStakeScriptHashScript for more consistent naming.
Finally, the tests are updated accordingly.
The following is a before and after comparison of analyzing a large
script:
benchmark old ns/op new ns/op delta
-------------------------------------------------------------------
BenchmarkIsAnyKindOfScriptHash 101249 3.83 -100.00%
benchmark old allocs new allocs delta
-------------------------------------------------------------------
BenchmarkIsAnyKindOfScriptHash 1 0 -100.00%
benchmark old bytes new bytes delta
-------------------------------------------------------------------
BenchmarkIsAnyKindOfScriptHash 466944 0 -100.00%
This adds tests to ensure the isAnyKindOfScriptHash function properly
identifies the four stake-tagged pay-to-script-hash possibilities in
addition to ensuring they are not misidentified as standard
pay-to-script-hash scripts.
This introduces a new function named calcSignatureHashRaw which accepts
the raw script bytes to calculate the script hash versus requiring the
parsed opcode only to unparse them later in order to make it more
flexible for working with raw scripts.
Since there are several places in the rest of the code that currently
only have access to the parsed opcodes, this modifies the existing
calcSignatureHash to first unparse the script before calling the new
function.
Note that the code in the signature hash calculation to remove all
instances of OP_CODESEPARATOR from the script is removed because that is
a holdover from BTC code which does not apply to v0 Decred scripts since
OP_CODESEPARATOR is completely disabled in Decred and thus there can
never actually be one in the script.
Finally, it removes the removeOpcode function and related tests since it
is no longer used.
This converts the majority of script errors from generic errors created
via errors.New and fmt.Errorf to use a concrete type that implements the
error interface with an error code and description.
This allows callers to programmatically detect the type of error via
type assertions and an error code while still allowing the errors to
provide more context.
For example, instead of just having an error the reads "disabled opcode"
as would happen prior to these changes when a disabled opcode is
encountered, the error will now read "attempt to execute disabled opcode
OP_FOO".
While it was previously possible to programmatically detect many errors
due to them being exported, they provided no additional context and
there were also various instances that were just returning errors
created on the spot which callers could not reliably detect without
resorting to looking at the actual error message, which is nearly always
bad practice.
Also, while here, export the MaxStackSize and MaxScriptSize constants
since they can be useful for consumers of the package and perform some
minor cleanup of some of the tests.
Putting the test code in the same package makes it easier for forks
since they don't have to change the import paths as much and it also
gets rid of the need for internal_test.go to bridge.
Also, do some light cleanup on a few tests while here.
This moves the logic to calculate the signature hash and the associated
test to separate files. Since there will ultimately be a new signature
algorithm, it makes sense to separate all logic related to signature
hashes for better code organization.
It contains no functional changes.
This modifies the exported CalcSignatureHash function to accept a script
as bytes instead of an array of parsed opcodes which are not available
to callers outside of the package.
While here, it also adds a proper comment for the exported function
since it is intended for more than testing as the previous comment
claimed.
Finally, it updates the tests to use a valid script instead of the
previous impossible to achieve constructed series of parsed opcodes.
This modifies the script engine to replace OP_UNKNOWN192 with OP_SHA256
along with a flag named ScriptVerifySHA256 to selectively enable its
enforcement.
The new opcode consumes the top item from the data stack, computes its
SHA-256, and pushes the resulting digest back to the data stack.
Since it requires an item on the data stack, execution will terminate
with an error when the stack is empty. This behavior differs from
OP_UNKNOWN192 which does not consume any elements from the data stack
and therefore makes this is hard-forking change when interpreted with
the new semantics due to the ScriptVerifySHA256 flag being set. Code to
selectively enable the opcode based on the result of an agenda vote will
be added in a separate commit.
This also includes tests to ensure the opcode works as expected
including when used both correctly and incorrectly.
Decred's serialized format for transactions split the 32-bit version
field into two 16-bit components such that the upper bits are used to
encode a serialization type and the lower 16 bits are the actual
transaction version.
Unfortunately, when this was done, the in-memory transaction struct was
not also updated to hide this complexity, which means that callers
currently have to understand and take special care when dealing with the
version field of the transaction.
Since the main purpose of the wire package is precisely to hide these
details, this remedies the situation by introducing a new field on the
in-memory transaction struct named SerType which houses the
serialization type and changes the Version field back to having the
desired semantics of actually being the real transaction version. Also,
since the maximum version can only be a 16-bit value, the Version field
has been changed to a uint16 to properly reflect this.
The serialization and deserialization functions now deal with properly
converting to and from these fields to the actual serialized format as
intended.
Finally, these changes also include a fairly significant amount of
related code cleanup and optimization along with some bug fixes in order
to allow the transaction version to be bumped as intended.
The following is an overview of all changes:
- Introduce new SerType field to MsgTx to specify the serialization type
- Change MsgTx.Version to a uint16 to properly reflect its maximum
allowed value
- Change the semantics of MsgTx.Version to be the actual transaction
version as intended
- Update all callers that had special code to deal with the previous
Version field semantics to use the new semantics
- Switch all of the code that deals with encoding and decoding the
serialized version field to use more efficient masks and shifts
instead of binary writes into buffers which cause allocations
- Correct several issues that would prevent producing expected
serializations for transactions with actual transaction versions that
are not 1
- Simplify the various serialize functions to use a single func which
accepts the serialization type to reduce code duplication
- Make serialization type switch usage more consistent with the rest of
the code base
- Update the utxoview and related code to use uint16s for the
transaction version as well since it should not care about the
serialization type due to using its own
- Make code more consistent in how it uses bytes.Buffer
- Clean up several of the comments regarding hashes and add some new
comments to better describe the serialization types
Contains the following commits:
- 711f33450c
- b6b1e55d1e
- Reverted because Travis is already at a more recent version
- bd4e64d1d4
Also, the merge commit contains the necessary decred-specific
alterations, converts all other references to sha to hash to keep with
the spirit of the merged commits, and various other cleanup intended to
bring the code bases more in line with one another.
This commit is the first stage of several that are planned to convert
the blockchain package into a concurrent safe package that will
ultimately allow support for multi-peer download and concurrent chain
processing. The goal is to update btcd proper after each step so it can
take advantage of the enhancements as they are developed.
In addition to the aforementioned benefit, this staged approach has been
chosen since it is absolutely critical to maintain consensus.
Separating the changes into several stages makes it easier for reviewers
to logically follow what is happening and therefore helps prevent
consensus bugs. Naturally there are significant automated tests to help
prevent consensus issues as well.
The main focus of this stage is to convert the blockchain package to use
the new database interface and implement the chain-related functionality
which it no longer handles. It also aims to improve efficiency in
various areas by making use of the new database and chain capabilities.
The following is an overview of the chain changes:
- Update to use the new database interface
- Add chain-related functionality that the old database used to handle
- Main chain structure and state
- Transaction spend tracking
- Implement a new pruned unspent transaction output (utxo) set
- Provides efficient direct access to the unspent transaction outputs
- Uses a domain specific compression algorithm that understands the
standard transaction scripts in order to significantly compress them
- Removes reliance on the transaction index and paves the way toward
eventually enabling block pruning
- Modify the New function to accept a Config struct instead of
inidividual parameters
- Replace the old TxStore type with a new UtxoViewpoint type that makes
use of the new pruned utxo set
- Convert code to treat the new UtxoViewpoint as a rolling view that is
used between connects and disconnects to improve efficiency
- Make best chain state always set when the chain instance is created
- Remove now unnecessary logic for dealing with unset best state
- Make all exported functions concurrent safe
- Currently using a single chain state lock as it provides a straight
forward and easy to review path forward however this can be improved
with more fine grained locking
- Optimize various cases where full blocks were being loaded when only
the header is needed to help reduce the I/O load
- Add the ability for callers to get a snapshot of the current best
chain stats in a concurrent safe fashion
- Does not block callers while new blocks are being processed
- Make error messages that reference transaction outputs consistently
use <transaction hash>:<output index>
- Introduce a new AssertError type an convert internal consistency
checks to use it
- Update tests and examples to reflect the changes
- Add a full suite of tests to ensure correct functionality of the new
code
The following is an overview of the btcd changes:
- Update to use the new database and chain interfaces
- Temporarily remove all code related to the transaction index
- Temporarily remove all code related to the address index
- Convert all code that uses transaction stores to use the new utxo
view
- Rework several calls that required the block manager for safe
concurrency to use the chain package directly now that it is
concurrent safe
- Change all calls to obtain the best hash to use the new best state
snapshot capability from the chain package
- Remove workaround for limits on fetching height ranges since the new
database interface no longer imposes them
- Correct the gettxout RPC handler to return the best chain hash as
opposed the hash the txout was found in
- Optimize various RPC handlers:
- Change several of the RPC handlers to use the new chain snapshot
capability to avoid needlessly loading data
- Update several handlers to use new functionality to avoid accessing
the block manager so they are able to return the data without
blocking when the server is busy processing blocks
- Update non-verbose getblock to avoid deserialization and
serialization overhead
- Update getblockheader to request the block height directly from
chain and only load the header
- Update getdifficulty to use the new cached data from chain
- Update getmininginfo to use the new cached data from chain
- Update non-verbose getrawtransaction to avoid deserialization and
serialization overhead
- Update gettxout to use the new utxo store versus loading
full transactions using the transaction index
The following is an overview of the utility changes:
- Update addblock to use the new database and chain interfaces
- Update findcheckpoint to use the new database and chain interfaces
- Remove the dropafter utility which is no longer supported
NOTE: The transaction index and address index will be reimplemented in
another commit.
Legacy transaction deep copy code mandated by the Bitcoin protocol
caused large amounts of data to be copied needlessly. If the
optimization for SigHashAll is set in chaincfg/params.go, these
extra copies are avoided by directly writing the pkScript and
decorations to a buffer and then hashing to get a witness hash,
while using the cached hash for the prefix.
Fixes#126.
IsUnspendable takes a public key script and returns whether it is
spendable.
Additionally, hook this into the mempool isDust function, since
unspendable outputs can't be spent.
This mimics Bitcoin Core commit 0aad1f13b2430165062bf9436036c1222a8724da
IsUnspendable takes a public key script and returns whether it is
spendable.
Additionally, hook this into the mempool isDust function, since
unspendable outputs can't be spent.
This mimics Bitcoin Core commit 0aad1f13b2430165062bf9436036c1222a8724da
- Move reference tests to test package since they are intended to
exercise the engine as callers would
- Improve the short form script parsing to allow additional opcodes:
DATA_#, OP_#, FALSE, TRUE
- Make use of a function to decode hex strings rather than manually
defining byte slices
- Update the tests to make use of the short form script parsing logic
rather than manually defining byte slices
- Consistently replace all []byte{} and [][]byte{} with nil
- Define tests only used in a specific function inside that func
- Move invalid flag combination test to engine_test since that is what
it is testing
- Remove all redundant script tests in favor of the JSON-based tests in
the data directory.
- Move several functions from internal_test.go to the test files
associated with what the tests are checking
This commit moves all code related to standard scripts into a separate
file named standard.go as well as the associated tests into
standard_test.go. Since the code in address.go and address_test.go is
only related to standard scripts, it has been combined into the new
files and the old files deleted.
The intent here is to make it clear that the code in standard.go is not
related to consensus.
This commit contains a lot of cleanup on the txscript code to make it
more consistent with the code throughout the rest of the project. It
doesn't change any operational logic.
The following is an overview of the changes:
- Add a significant number of comments throughout in order to better
explain what the code is doing
- Fix several comment typos
- Move a couple of constants only used by the engine to engine.go
- Move a variable only used by the engine to engine.go
- Fix a couple of format specifiers in the test prints
- Reorder functions so they're defined before/closer to use
- Make the code lint clean with the exception of the opcode definitions
This commit renames the Script type to Engine to better reflect its
purpose. It also renames the NewScript function to NewEngine to match.
This is being done because name Script for the engine is confusing since
it implies it is an actual script rather than the execution environment
for the script. It also paves the way for eventually supplying a
ParsedScript type which will be less likely to be confused with the
execution environment.
While moving the code, some additional variable names and comments have
been updated to better match the style used throughout the rest of the
code base. In addition, an attempt has been made to use consistent naming
of the engine as 'vm' instead of using different variables names as it was
previously.
Finally, the relevant engine code has been moved into a new file named
engine.go and related tests moved to engine_test.go.
This commit removes the unnecessary sigScript parameter from the
txscript.NewScript function. This has bothered me for a while because it
can and really should be obtained from the provided transaction and input
index. The way it was, the passed script could technically be different
than what is in the transaction. Obviously that would be an improper use
of the API, but it's safer and more convenient to simply pull it from the
provided transaction and index.
Also, since the function signature is changing anyways, make the input
index parameter come after the transaction which it references.
The ScriptVerifyCleanStack flag requires that only a single
stack element remains after evaluation and that when interpreted
as a bool, it must be true. This is BIP0062, rule 6.
This mimics Bitcoin Core commit b6e03cc59208305681745ad06f2056ffe6690597
This change increases the maximum allowed bytes allowed in pushed
data to be considered a nulldata transaction. This matches the current
value the reference implementation uses by default.
