More like till an alt-coin dev sees the thread.
I got my fingers crossed a dev runs across it, ill keep checking in 
Topic: How do you create an altcoin? - page 10. (Read 21864 times)
legendary
Activity: 1862
Merit: 1011
Reverse engineer from time to time
More like till an alt-coin dev sees the thread.
Is this whole thing on hold till we can get someone to help with the genesis block?
If Sunny King can help us, it'd be nice. But I guess the reason the genesis block creation information is not found easily is because every noob(me included) on the block will have an alt-currency out by the end of the day.
It's open source... it may be obscure... but that doesn't mean people don't have a right to know how to do it.
By the end of this thread hopefully we'll all know how it works!
We'll figure it out
If Sunny King can help us, it'd be nice. But I guess the reason the genesis block creation information is not found easily is because every noob(me included) on the block will have an alt-currency out by the end of the day.
It's open source... it may be obscure... but that doesn't mean people don't have a right to know how to do it.
By the end of this thread hopefully we'll all know how it works!
We'll figure it out
If Sunny King can help us, it'd be nice. But I guess the reason the genesis block creation information is not found easily is because every noob(me included) on the block will have an alt-currency out by the end of the day.
It's open source... it may be obscure... but that doesn't mean people don't have a right to know how to do it.
By the end of this thread hopefully we'll all know how it works!
legendary
Activity: 1862
Merit: 1011
Reverse engineer from time to time
If Sunny King can help us, it'd be nice. But I guess the reason the genesis block creation information is not found easily is because every noob(me included) on the block will have an alt-currency out by the end of the day.
It's open source... it may be obscure... but that doesn't mean people don't have a right to know how to do it.
By the end of this thread hopefully we'll all know how it works!
If Sunny King can help us, it'd be nice. But I guess the reason the genesis block creation information is not found easily is because every noob(me included) on the block will have an alt-currency out by the end of the day.
It's open source... it may be obscure... but that doesn't mean people don't have a right to know how to do it.
By the end of this thread hopefully we'll all know how it works!
If Sunny King can help us, it'd be nice. But I guess the reason the genesis block creation information is not found easily is because every noob(me included) on the block will have an alt-currency out by the end of the day.
But then how did altcoin authors create theirs? 
legendary
Activity: 1862
Merit: 1011
Reverse engineer from time to time
If Sunny King can help us, it'd be nice. But I guess the reason the genesis block creation information is not found easily is because every noob(me included) on the block will have an alt-currency out by the end of the day.
But then how did altcoin authors create theirs? Perhaps, but a q on this. Do you really want to create a sha256 alt, or LiteCoin (or better yet PPCoin) type chain instead?
Really either is fine at this point im just trying to get somthing running
legendary
Activity: 1862
Merit: 1011
Reverse engineer from time to time
Ive made a discovery... i think??
That's where I derived my information from, by following the functions.
Perhaps, but a q on this. Do you really want to create a sha256 alt, or LiteCoin (or better yet PPCoin) type chain instead?
If Sunny King can help us, it'd be nice. But I guess the reason the genesis block creation information is not found easily is because every noob(me included) on the block will have an alt-currency out by the end of the day.
But then how did altcoin authors create theirs?
Ive made a discovery... i think??
Starting on line 1,985 of main.cpp
Starting on line 1,985 of main.cpp
Code:
//
// Init with genesis block
//
if (mapBlockIndex.empty())
{
if (!fAllowNew)
return false;
// Genesis Block:
// CBlock(hash=12a765e31ffd4059bada, PoW=0000050c34a64b415b6b, ver=1, hashPrevBlock=00000000000000000000, hashMerkleRoot=97ddfbbae6, nTime=1317972665, nBits=1e0ffff0, nNonce=2084524493, vtx=1)
// CTransaction(hash=97ddfbbae6, ver=1, vin.size=1, vout.size=1, nLockTime=0)
// CTxIn(COutPoint(0000000000, -1), coinbase 04ffff001d0104404e592054696d65732030352f4f63742f32303131205374657665204a6f62732c204170706c65e280997320566973696f6e6172792c2044696573206174203536)
// CTxOut(nValue=50.00000000, scriptPubKey=040184710fa689ad5023690c80f3a4)
// vMerkleTree: 97ddfbbae6
// Genesis block
const char* pszTimestamp = "NY Times 05/Oct/2011 Steve Jobs, Apple’s Visionary, Dies at 56";
CTransaction txNew;
txNew.vin.resize(1);
txNew.vout.resize(1);
txNew.vin[0].scriptSig = CScript() << 486604799 << CBigNum(4) << vector((const unsigned char*)pszTimestamp, (const unsigned char*)pszTimestamp + strlen(pszTimestamp));
txNew.vout[0].nValue = 50 * COIN;
txNew.vout[0].scriptPubKey = CScript() << ParseHex("040184710fa689ad5023690c80f3a49c8f13f8d45b8c857fbcbc8bc4a8e4d3eb4b10f4d4604fa08dce601aaf0f470216fe1b51850b4acf21b179c45070ac7b03a9") << OP_CHECKSIG;
CBlock block;
block.vtx.push_back(txNew);
block.hashPrevBlock = 0;
block.hashMerkleRoot = block.BuildMerkleTree();
block.nVersion = 1;
block.nTime = 1317972665;
block.nBits = 0x1e0ffff0;
block.nNonce = 2084524493;
if (fTestNet)
{
block.nTime = 1317798646;
block.nNonce = 385270584;
}
legendary
Activity: 1862
Merit: 1011
Reverse engineer from time to time
If Sunny King can help us, it'd be nice. But I guess the reason the genesis block creation information is not found easily is because every noob(me included) on the block will have an alt-currency out by the end of the day.
legendary
Activity: 1862
Merit: 1011
Reverse engineer from time to time
Ok, so we basically have this
What we are interested in is, BuildMerkleTree which is found in main.h
Next we are interested in this, I believe.
since we have only one transaction, this will return as soon as it computes the has. So we see tx.GetHash, and that tx is of type CTransaction, so we head in that class, which is in main.h again
and see this coide
which passes the instance of the object to SerializeHash. SerializeHash is located in hash.h
Here we see that the object is written(I think, not sure) to ss which is an instance of CHashWriter which is also in main.h and that is where the funky business happens that is uber hard to understand.
But here we go,
CHashWriter, small, but deadly. I guess what we are further interested in, is
which as you calls some global function Serialize that may or may not be located in serialize.h
Code:
const char* pszTimestamp = "The Times 03/Jan/2009 Chancellor on brink of second bailout for banks";
CTransaction txNew;
txNew.vin.resize(1);
txNew.vout.resize(1);
txNew.vin[0].scriptSig = CScript() << 486604799 << CBigNum(4) << vector((const unsigned char*)pszTimestamp, (const unsigned char*)pszTimestamp + strlen(pszTimestamp));
txNew.vout[0].nValue = 50 * COIN;
txNew.vout[0].scriptPubKey = CScript() << ParseHex("04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d578a4c702b6bf11d5f") << OP_CHECKSIG;
CBlock block;
block.vtx.push_back(txNew);
block.hashPrevBlock = 0;
block.hashMerkleRoot = block.BuildMerkleTree();
What we are interested in is, BuildMerkleTree which is found in main.h
Code:
uint256 BuildMerkleTree() const
{
vMerkleTree.clear();
BOOST_FOREACH(const CTransaction& tx, vtx)
vMerkleTree.push_back(tx.GetHash());
int j = 0;
for (int nSize = vtx.size(); nSize > 1; nSize = (nSize + 1) / 2)
{
for (int i = 0; i < nSize; i += 2)
{
int i2 = std::min(i+1, nSize-1);
vMerkleTree.push_back(Hash(BEGIN(vMerkleTree[j+i]), END(vMerkleTree[j+i]),
BEGIN(vMerkleTree[j+i2]), END(vMerkleTree[j+i2])));
}
j += nSize;
}
return (vMerkleTree.empty() ? 0 : vMerkleTree.back());
}
Next we are interested in this, I believe.
Code:
vMerkleTree.push_back(tx.GetHash());
and see this coide
Code:
uint256 GetHash() const
{
return SerializeHash(*this);
}
which passes the instance of the object to SerializeHash. SerializeHash is located in hash.h
Code:
template
uint256 SerializeHash(const T& obj, int nType=SER_GETHASH, int nVersion=PROTOCOL_VERSION)
{
CHashWriter ss(nType, nVersion);
ss << obj;
return ss.GetHash();
}
Here we see that the object is written(I think, not sure) to ss which is an instance of CHashWriter which is also in main.h and that is where the funky business happens that is uber hard to understand.
But here we go,
Code:
class CHashWriter
{
private:
SHA256_CTX ctx;
public:
int nType;
int nVersion;
void Init() {
SHA256_Init(&ctx);
}
CHashWriter(int nTypeIn, int nVersionIn) : nType(nTypeIn), nVersion(nVersionIn) {
Init();
}
CHashWriter& write(const char *pch, size_t size) {
SHA256_Update(&ctx, pch, size);
return (*this);
}
// invalidates the object
uint256 GetHash() {
uint256 hash1;
SHA256_Final((unsigned char*)&hash1, &ctx);
uint256 hash2;
SHA256((unsigned char*)&hash1, sizeof(hash1), (unsigned char*)&hash2);
return hash2;
}
template
CHashWriter& operator<<(const T& obj) {
// Serialize to this stream
::Serialize(*this, obj, nType, nVersion);
return (*this);
}
};
CHashWriter, small, but deadly. I guess what we are further interested in, is
Code:
template
CHashWriter& operator<<(const T& obj) {
// Serialize to this stream
::Serialize(*this, obj, nType, nVersion);
return (*this);
}
Didn't read all through it yet but maybe this helps? https://bitcointalksearch.org/topic/how-is-the-genesis-block-made-171355
legendary
Activity: 1862
Merit: 1011
Reverse engineer from time to time
In addition 5th said you need a valid Merkle root... that the one in his code was for illustration.
Someone with experience will need to chime in on that one.
Truth be told I dig deep and deep in Bitcoin's source and it does some kind of serialization of objects and stuff and finally produces a merkle root hash..seriously ridiculously hard to even figure out what the hell happens. Someone with experience will need to chime in on that one.
Your post count is 666 and you mentioned hell on your 666 post. :|
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