Purchase

Utility

0x5bf8e92a5727...cda7362bc166

FrontierContract #3,837Exact Bytecode MatchEdit this contract

Deployed November 13, 2015 (10 years ago)Block 534,352

Safe remote purchase escrow holding a double deposit from both sides

Frontier EraVerified Source

Context

Deployed in November 2015 during the Frontier period, when the Solidity documentation examples were the main source of contract code in circulation.

Key Facts

Deployer

0xd05e10...f027c4

Deployment Block

534,352

Deployment Date

Nov 13, 2015, 01:48 PM

Code Size

1.8 KB

Gas at Deploy

537,072

Deployment Transaction: 0x54425c6b5ff8ff66...5676cd0511f93c29

Description

An escrow for a remote sale. The seller deploys the contract with twice the item price, which the constructor halves and records as the value. A buyer locks the sale by sending the same doubled amount through confirmPurchase. Calling confirmReceived returns the buyer's deposit and pays the seller the rest, and refund lets the seller unwind a locked sale instead. State transitions are guarded by a three-value enum and by modifiers that restrict each call to the buyer or the seller. It is an edited copy of the safe remote purchase example from the Solidity documentation, with a refund path and capitalised events added.

Source Verified

Exact bytecode match(1,871 bytes)

Compiler: v0.1.5+

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Heuristic Analysis

The following characteristics were detected through bytecode analysis and may not be accurate.

Detected Type: Utility

Frontier Era

The initial release of Ethereum. A bare-bones implementation for technical users.

Block span: 0 — 1,149,999

July 30, 2015 — March 14, 2016

Bytecode Overview

Opcodes1,871

Unique Opcodes160

Jump Instructions61

Storage Operations37

Verified Source Available

Source verified through compiler archaeology and exact bytecode matching.

Verified on Etherscan

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Show source code (Solidity)

// Submitted by EthereumHistory (ethereumhistory.com)
contract Purchase {
    uint public value;
    address public seller;
    address public buyer;
    enum State { Created, Locked, Inactive }
    State public state;

    function Purchase() require(msg.value % 2 == 0) {
        seller = msg.sender;
        value = msg.value / 2;
    }

    modifier require(bool _condition) {
        if (!_condition) throw;
        _
    }

    modifier onlyBuyer() {
        if (msg.sender != buyer) throw;
        _
    }

    modifier onlySeller() {
        if (msg.sender != seller) throw;
        _
    }

    modifier inState(State _state) {
        if (state != _state) throw;
        _
    }

    event Aborted();
    event PurchaseConfirmed();
    event ItemReceived();
    event Refunded();

    function abort()
        onlySeller
        inState(State.Created)
    {
        seller.send(this.balance);
        state = State.Inactive;
        Aborted();
    }

    function confirmPurchase()
        inState(State.Created)
        require(msg.value == 2 * value)
    {
        buyer = msg.sender;
        state = State.Locked;
        PurchaseConfirmed();
    }

    function confirmReceived()
        onlyBuyer
        inState(State.Locked)
    {
        buyer.send(value);
        seller.send(this.balance);
        state = State.Inactive;
        ItemReceived();
    }

    function refund()
        onlySeller
        inState(State.Locked)
    {
        buyer.send(2 * value);
        seller.send(this.balance);
        state = State.Inactive;
        Refunded();
    }

    function() {
        throw;
    }
}