blockpp
/
src
/
blockchain.cc
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76#include "blockchain.hh"
using Data = Blockchain::Data;
using Block = Blockchain::Block;
#include "crypto.hh"
#include <string>
#include <sstream>
#include <vector>
#include <ctime>
Blockchain::Blockchain()
{
}
void Blockchain::genesis_block()
{
Block block;
block.index = 0;
block.timestamp = std::time(nullptr);
block.data = "Genesis Block";
block.hash_prev = "";
chain.emplace_back(block);
}
std::string Blockchain::hash_block(Block block)
{
std::stringstream sum;
sum << block.index << block.timestamp << block.data << block.hash_prev;
return (Crypto::sha256(sum.str()));
}
Block Blockchain::generate_block(Data data)
{
Block block;
block.index = chain.size();
block.timestamp = std::time(nullptr);
block.data = data.str;
block.hash_prev = chain.back().hash;
block.hash = hash_block(block);
return block;
}
bool Blockchain::validate_block(Block block, Block block_prev)
{
bool valid {true};
if (block.index != block_prev.index + 1)
{
valid = false;
}
else if (block.hash_prev != block_prev.hash)
{
valid = false;
}
else if (hash_block(block) != block.hash)
{
valid = false;
}
return valid;
}
int Blockchain::append_block(Data data)
{
Block block {generate_block(data)};
int status {0};
if (validate_block(block, chain.back()))
{
chain.emplace_back(block);
status = 0;
}
else
{
status = -1;
}
return status;
}