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author | JM <jm@dexon.org> | 2019-01-15 23:33:28 +0800 |
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committer | GitHub <noreply@github.com> | 2019-01-15 23:33:28 +0800 |
commit | 020c8a477578cef3764b54f33d9ca0cf6caf7631 (patch) | |
tree | 08a669a19cc428b8c48dad180f1f32096885826b /core/vm/contract.go | |
parent | bdde6109ffa6fa4d295708a2a75271186a12c761 (diff) | |
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core: vm: refactor file structure (#151)
For support other vm types, this pr modified the core/vm file
structures.
Diffstat (limited to 'core/vm/contract.go')
-rw-r--r-- | core/vm/contract.go | 184 |
1 files changed, 0 insertions, 184 deletions
diff --git a/core/vm/contract.go b/core/vm/contract.go deleted file mode 100644 index 751da072e..000000000 --- a/core/vm/contract.go +++ /dev/null @@ -1,184 +0,0 @@ -// Copyright 2015 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 <http://www.gnu.org/licenses/>. - -package vm - -import ( - "math/big" - - "github.com/dexon-foundation/dexon/common" -) - -// ContractRef is a reference to the contract's backing object -type ContractRef interface { - Address() common.Address -} - -// AccountRef implements ContractRef. -// -// Account references are used during EVM initialisation and -// it's primary use is to fetch addresses. Removing this object -// proves difficult because of the cached jump destinations which -// are fetched from the parent contract (i.e. the caller), which -// is a ContractRef. -type AccountRef common.Address - -// Address casts AccountRef to a Address -func (ar AccountRef) Address() common.Address { return (common.Address)(ar) } - -// Contract represents an ethereum contract in the state database. It contains -// the contract code, calling arguments. Contract implements ContractRef -type Contract struct { - // CallerAddress is the result of the caller which initialised this - // contract. However when the "call method" is delegated this value - // needs to be initialised to that of the caller's caller. - CallerAddress common.Address - caller ContractRef - self ContractRef - - jumpdests map[common.Hash]bitvec // Aggregated result of JUMPDEST analysis. - analysis bitvec // Locally cached result of JUMPDEST analysis - - Code []byte - CodeHash common.Hash - CodeAddr *common.Address - Input []byte - - Gas uint64 - value *big.Int -} - -// NewContract returns a new contract environment for the execution of EVM. -func NewContract(caller ContractRef, object ContractRef, value *big.Int, gas uint64) *Contract { - c := &Contract{CallerAddress: caller.Address(), caller: caller, self: object} - - if parent, ok := caller.(*Contract); ok { - // Reuse JUMPDEST analysis from parent context if available. - c.jumpdests = parent.jumpdests - } else { - c.jumpdests = make(map[common.Hash]bitvec) - } - - // Gas should be a pointer so it can safely be reduced through the run - // This pointer will be off the state transition - c.Gas = gas - // ensures a value is set - c.value = value - - return c -} - -func (c *Contract) validJumpdest(dest *big.Int) bool { - udest := dest.Uint64() - // PC cannot go beyond len(code) and certainly can't be bigger than 63bits. - // Don't bother checking for JUMPDEST in that case. - if dest.BitLen() >= 63 || udest >= uint64(len(c.Code)) { - return false - } - // Only JUMPDESTs allowed for destinations - if OpCode(c.Code[udest]) != JUMPDEST { - return false - } - // Do we have a contract hash already? - if c.CodeHash != (common.Hash{}) { - // Does parent context have the analysis? - analysis, exist := c.jumpdests[c.CodeHash] - if !exist { - // Do the analysis and save in parent context - // We do not need to store it in c.analysis - analysis = codeBitmap(c.Code) - c.jumpdests[c.CodeHash] = analysis - } - return analysis.codeSegment(udest) - } - // We don't have the code hash, most likely a piece of initcode not already - // in state trie. In that case, we do an analysis, and save it locally, so - // we don't have to recalculate it for every JUMP instruction in the execution - // However, we don't save it within the parent context - if c.analysis == nil { - c.analysis = codeBitmap(c.Code) - } - return c.analysis.codeSegment(udest) -} - -// AsDelegate sets the contract to be a delegate call and returns the current -// contract (for chaining calls) -func (c *Contract) AsDelegate() *Contract { - // NOTE: caller must, at all times be a contract. It should never happen - // that caller is something other than a Contract. - parent := c.caller.(*Contract) - c.CallerAddress = parent.CallerAddress - c.value = parent.value - - return c -} - -// GetOp returns the n'th element in the contract's byte array -func (c *Contract) GetOp(n uint64) OpCode { - return OpCode(c.GetByte(n)) -} - -// GetByte returns the n'th byte in the contract's byte array -func (c *Contract) GetByte(n uint64) byte { - if n < uint64(len(c.Code)) { - return c.Code[n] - } - - return 0 -} - -// Caller returns the caller of the contract. -// -// Caller will recursively call caller when the contract is a delegate -// call, including that of caller's caller. -func (c *Contract) Caller() common.Address { - return c.CallerAddress -} - -// UseGas attempts the use gas and subtracts it and returns true on success -func (c *Contract) UseGas(gas uint64) (ok bool) { - if c.Gas < gas { - return false - } - c.Gas -= gas - return true -} - -// Address returns the contracts address -func (c *Contract) Address() common.Address { - return c.self.Address() -} - -// Value returns the contracts value (sent to it from it's caller) -func (c *Contract) Value() *big.Int { - return c.value -} - -// SetCallCode sets the code of the contract and address of the backing data -// object -func (c *Contract) SetCallCode(addr *common.Address, hash common.Hash, code []byte) { - c.Code = code - c.CodeHash = hash - c.CodeAddr = addr -} - -// SetCodeOptionalHash can be used to provide code, but it's optional to provide hash. -// In case hash is not provided, the jumpdest analysis will not be saved to the parent context -func (c *Contract) SetCodeOptionalHash(addr *common.Address, codeAndHash *codeAndHash) { - c.Code = codeAndHash.code - c.CodeHash = codeAndHash.hash - c.CodeAddr = addr -} |