Chainparams: Introduce consensus.genesis_style for compatibility and sanity

Author: jtimon

src/chainparams.cpp

@@ -4,9 +4,10 @@
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <chainparams.h>
-#include <consensus/merkle.h>
 
 #include <chainparamsseeds.h>
+#include <consensus/merkle.h>
+#include <hash.h>
 #include <tinyformat.h>
 #include <util.h>
 #include <utilstrencodings.h>
@@ -17,13 +18,13 @@
 #include <boost/algorithm/string/classification.hpp>
 #include <boost/algorithm/string/split.hpp>
 
-static CBlock CreateGenesisBlock(const char* pszTimestamp, const CScript& genesisOutputScript, uint32_t nTime, uint32_t nNonce, uint32_t nBits, int32_t nVersion, const CAmount& genesisReward)
+static CBlock CreateGenesisBlock(const CScript& coinbase_sig, const CScript& genesisOutputScript, uint32_t nTime, uint32_t nNonce, uint32_t nBits, int32_t nVersion, const CAmount& genesisReward)
 {
     CMutableTransaction txNew;
     txNew.nVersion = 1;
     txNew.vin.resize(1);
     txNew.vout.resize(1);
-    txNew.vin[0].scriptSig = CScript() << 486604799 << CScriptNum(4) << std::vector<unsigned char>((const unsigned char*)pszTimestamp, (const unsigned char*)pszTimestamp + strlen(pszTimestamp));
+    txNew.vin[0].scriptSig = coinbase_sig;
     txNew.vout[0].nValue = genesisReward;
     txNew.vout[0].scriptPubKey = genesisOutputScript;
 
@@ -38,6 +39,12 @@ static CBlock CreateGenesisBlock(const char* pszTimestamp, const CScript& genesi
     return genesis;
 }
 
+static CBlock CreateGenesisBlock(const char* pszTimestamp, const CScript& genesisOutputScript, uint32_t nTime, uint32_t nNonce, uint32_t nBits, int32_t nVersion, const CAmount& genesisReward)
+{
+    CScript coinbase_sig = CScript() << 486604799 << CScriptNum(4) << std::vector<unsigned char>((const unsigned char*)pszTimestamp, (const unsigned char*)pszTimestamp + strlen(pszTimestamp));
+    return CreateGenesisBlock(coinbase_sig, genesisOutputScript, nTime, nNonce, nBits, nVersion, genesisReward);
+}
+
 /**
  * Build the genesis block. Note that the output of its generation
  * transaction cannot be spent since it did not originally exist in the
@@ -403,6 +410,7 @@ class CCustomParams : public CRegTestParams {
     {
         UpdateVersionBitsParametersFromArgs(args);
 
+        consensus.genesis_style = args.GetArg("-con_genesis_style", "default_style");
         consensus.nSubsidyHalvingInterval = args.GetArg("-con_nsubsidyhalvinginterval", consensus.nSubsidyHalvingInterval);
         consensus.BIP16Exception = uint256S(args.GetArg("-con_bip16exception", "0x0"));
         consensus.BIP34Height = args.GetArg("-con_bip34height", consensus.BIP34Height);
@@ -457,12 +465,30 @@ class CCustomParams : public CRegTestParams {
         }
     }
 
+    void SetGenesisBlock()
+    {
+        if (consensus.genesis_style == "regtest2_style") {
+            // Same style as in https://github.com/bitcoin/bitcoin/pull/8994
+            genesis = CreateGenesisBlock(strNetworkID.c_str(), CScript(OP_TRUE), 1296688602, 2, 0x207fffff, 1, 50 * COIN);
+
+        } else if (consensus.genesis_style == "default_style") {
+            CHashWriter h(SER_DISK, 0);
+            h << strNetworkID;
+            uint256 hash = h.GetHash();
+            CScript coinbase_sig = CScript() << std::vector<uint8_t>(hash.begin(), hash.end());
+            genesis = CreateGenesisBlock(coinbase_sig, CScript(OP_TRUE), 1296688602, 2, 0x207fffff, 1, 50 * COIN);
+
+        } else {
+            throw std::runtime_error(strprintf("%s: Unknown consensus.genesis_style %s.", __func__, consensus.genesis_style));
+        }
+    }
+
 public:
     CCustomParams(const std::string& chain, ArgsManager& args) : CRegTestParams(args)
     {
         strNetworkID = chain;
         UpdateFromArgs(args);
-        genesis = CreateGenesisBlock(strNetworkID.c_str(), CScript(OP_TRUE), 1296688602, 2, 0x207fffff, 1, 50 * COIN);
+        SetGenesisBlock();
         consensus.hashGenesisBlock = genesis.GetHash();
     }
 };

src/chainparamsbase.cpp

@@ -21,6 +21,7 @@ void SetupChainParamsBaseOptions()
     gArgs.AddArg("-regtest", "Enter regression test mode, which uses a special chain in which blocks can be solved instantly. "
                                    "This is intended for regression testing tools and app development.", true, OptionsCategory::CHAINPARAMS);
     gArgs.AddArg("-testnet", "Use the test chain", false, OptionsCategory::CHAINPARAMS);
+    gArgs.AddArg("-con_genesis_style=<style>", "Use genesis style <style> (default: default_style). Allowed values: default_style, regtest2_style", true, OptionsCategory::CHAINPARAMS);
     gArgs.AddArg("-vbparams=deployment:start:end", "Use given start/end times for specified version bits deployment (regtest or custom only)", true, OptionsCategory::CHAINPARAMS);
     gArgs.AddArg("-con_mandatorycoinbase", "All non-zero valued coinbase outputs must go to this scriptPubKey, if set.", false, OptionsCategory::CHAINPARAMS);
     gArgs.AddArg("-seednode=<ip>", "Use specified node as seed node. This option can be specified multiple times to connect to multiple nodes. (custom only)", true, OptionsCategory::CHAINPARAMS);

src/consensus/params.h

@@ -49,6 +49,7 @@ struct BIP9Deployment {
  * Parameters that influence chain consensus.
  */
 struct Params {
+    std::string genesis_style;
     uint256 hashGenesisBlock;
     int nSubsidyHalvingInterval;
     /* Block hash that is excepted from BIP16 enforcement */