Chainparams: Use a regular factory for creating chainparams

6 files changed, 58 insertions, 39 deletions

diff --git a/src/bitcoin-cli.cpp b/src/bitcoin-cli.cpp
index 5edd43d41e..885b787b4d 100644
--- a/src/bitcoin-cli.cpp
+++ b/src/bitcoin-cli.cpp
@@ -30,6 +30,8 @@ static const int CONTINUE_EXECUTION=-1;
 
 std::string HelpMessageCli()
 {
+    const auto defaultBaseParams = CreateBaseChainParams(CBaseChainParams::MAIN);
+    const auto testnetBaseParams = CreateBaseChainParams(CBaseChainParams::TESTNET);
     std::string strUsage;
     strUsage += HelpMessageGroup(_("Options:"));
     strUsage += HelpMessageOpt("-?", _("This help message"));
@@ -38,7 +40,7 @@ std::string HelpMessageCli()
     AppendParamsHelpMessages(strUsage);
     strUsage += HelpMessageOpt("-named", strprintf(_("Pass named instead of positional arguments (default: %s)"), DEFAULT_NAMED));
     strUsage += HelpMessageOpt("-rpcconnect=<ip>", strprintf(_("Send commands to node running on <ip> (default: %s)"), DEFAULT_RPCCONNECT));
-    strUsage += HelpMessageOpt("-rpcport=<port>", strprintf(_("Connect to JSON-RPC on <port> (default: %u or testnet: %u)"), BaseParams(CBaseChainParams::MAIN).RPCPort(), BaseParams(CBaseChainParams::TESTNET).RPCPort()));
+    strUsage += HelpMessageOpt("-rpcport=<port>", strprintf(_("Connect to JSON-RPC on <port> (default: %u or testnet: %u)"), defaultBaseParams->RPCPort(), testnetBaseParams->RPCPort()));
     strUsage += HelpMessageOpt("-rpcwait", _("Wait for RPC server to start"));
     strUsage += HelpMessageOpt("-rpcuser=<user>", _("Username for JSON-RPC connections"));
     strUsage += HelpMessageOpt("-rpcpassword=<pw>", _("Password for JSON-RPC connections"));
diff --git a/src/chainparams.cpp b/src/chainparams.cpp
index 1dc29826af..2d54dfa543 100644
--- a/src/chainparams.cpp
+++ b/src/chainparams.cpp
@@ -55,6 +55,12 @@ static CBlock CreateGenesisBlock(uint32_t nTime, uint32_t nNonce, uint32_t nBits
     return CreateGenesisBlock(pszTimestamp, genesisOutputScript, nTime, nNonce, nBits, nVersion, genesisReward);
 }
 
+void CChainParams::UpdateBIP9Parameters(Consensus::DeploymentPos d, int64_t nStartTime, int64_t nTimeout)
+{
+    consensus.vDeployments[d].nStartTime = nStartTime;
+    consensus.vDeployments[d].nTimeout = nTimeout;
+}
+
 /**
  * Main network
  */
@@ -165,7 +171,6 @@ public:
         };
     }
 };
-static CMainParams mainParams;
 
 /**
  * Testnet (v3)
@@ -253,7 +258,6 @@ public:
 
     }
 };
-static CTestNetParams testNetParams;
 
 /**
  * Regression test
@@ -326,42 +330,41 @@ public:
         base58Prefixes[EXT_PUBLIC_KEY] = boost::assign::list_of(0x04)(0x35)(0x87)(0xCF).convert_to_container<std::vector<unsigned char> >();
         base58Prefixes[EXT_SECRET_KEY] = boost::assign::list_of(0x04)(0x35)(0x83)(0x94).convert_to_container<std::vector<unsigned char> >();
     }
-
-    void UpdateBIP9Parameters(Consensus::DeploymentPos d, int64_t nStartTime, int64_t nTimeout)
-    {
-        consensus.vDeployments[d].nStartTime = nStartTime;
-        consensus.vDeployments[d].nTimeout = nTimeout;
-    }
 };
-static CRegTestParams regTestParams;
 
-static CChainParams *pCurrentParams = 0;
+static std::unique_ptr<CChainParams> globalChainParams;
+static std::unique_ptr<CChainParams> globalSwitchingChainParams;
 
 const CChainParams &Params() {
-    assert(pCurrentParams);
-    return *pCurrentParams;
+    assert(globalChainParams);
+    return *globalChainParams;
 }
 
-CChainParams& Params(const std::string& chain)
+std::unique_ptr<CChainParams> CreateChainParams(const std::string& chain)
 {
     if (chain == CBaseChainParams::MAIN)
-            return mainParams;
+        return std::unique_ptr<CChainParams>(new CMainParams());
     else if (chain == CBaseChainParams::TESTNET)
-            return testNetParams;
+        return std::unique_ptr<CChainParams>(new CTestNetParams());
     else if (chain == CBaseChainParams::REGTEST)
-            return regTestParams;
-    else
-        throw std::runtime_error(strprintf("%s: Unknown chain %s.", __func__, chain));
+        return std::unique_ptr<CChainParams>(new CRegTestParams());
+    throw std::runtime_error(strprintf("%s: Unknown chain %s.", __func__, chain));
+}
+
+const CChainParams& Params(const std::string& chain)
+{
+    globalSwitchingChainParams = CreateChainParams(chain);
+    return *globalSwitchingChainParams;
 }
 
 void SelectParams(const std::string& network)
 {
     SelectBaseParams(network);
-    pCurrentParams = &Params(network);
+    globalChainParams = CreateChainParams(network);
 }
 
-void UpdateRegtestBIP9Parameters(Consensus::DeploymentPos d, int64_t nStartTime, int64_t nTimeout)
+void UpdateBIP9Parameters(Consensus::DeploymentPos d, int64_t nStartTime, int64_t nTimeout)
 {
-    regTestParams.UpdateBIP9Parameters(d, nStartTime, nTimeout);
+    globalChainParams->UpdateBIP9Parameters(d, nStartTime, nTimeout);
 }
  
diff --git a/src/chainparams.h b/src/chainparams.h
index 4fe88c691c..a91570c22d 100644
--- a/src/chainparams.h
+++ b/src/chainparams.h
@@ -11,6 +11,7 @@
 #include "primitives/block.h"
 #include "protocol.h"
 
+#include <memory>
 #include <vector>
 
 struct CDNSSeedData {
@@ -75,6 +76,7 @@ public:
     const std::vector<SeedSpec6>& FixedSeeds() const { return vFixedSeeds; }
     const CCheckpointData& Checkpoints() const { return checkpointData; }
     const ChainTxData& TxData() const { return chainTxData; }
+    void UpdateBIP9Parameters(Consensus::DeploymentPos d, int64_t nStartTime, int64_t nTimeout);
 protected:
     CChainParams() {}
 
@@ -95,6 +97,13 @@ protected:
 };
 
 /**
+ * Creates and returns a std::unique_ptr<CChainParams> of the chosen chain.
+ * @returns a CChainParams* of the chosen chain.
+ * @throws a std::runtime_error if the chain is not supported.
+ */
+std::unique_ptr<CChainParams> CreateChainParams(const std::string& chain);
+
+/**
  * Return the currently selected parameters. This won't change after app
  * startup, except for unit tests.
  */
@@ -103,7 +112,7 @@ const CChainParams &Params();
 /**
  * @returns CChainParams for the given BIP70 chain name.
  */
-CChainParams& Params(const std::string& chain);
+const CChainParams& Params(const std::string& chain);
 
 /**
  * Sets the params returned by Params() to those for the given BIP70 chain name.
@@ -114,6 +123,6 @@ void SelectParams(const std::string& chain);
 /**
  * Allows modifying the BIP9 regtest parameters.
  */
-void UpdateRegtestBIP9Parameters(Consensus::DeploymentPos d, int64_t nStartTime, int64_t nTimeout);
+void UpdateBIP9Parameters(Consensus::DeploymentPos d, int64_t nStartTime, int64_t nTimeout);
 
 #endif // BITCOIN_CHAINPARAMS_H
diff --git a/src/chainparamsbase.cpp b/src/chainparamsbase.cpp
index d013cc1450..43c9a13c54 100644
--- a/src/chainparamsbase.cpp
+++ b/src/chainparamsbase.cpp
@@ -35,7 +35,6 @@ public:
         nRPCPort = 8332;
     }
 };
-static CBaseMainParams mainParams;
 
 /**
  * Testnet (v3)
@@ -49,7 +48,6 @@ public:
         strDataDir = "testnet3";
     }
 };
-static CBaseTestNetParams testNetParams;
 
 /*
  * Regression test
@@ -63,31 +61,30 @@ public:
         strDataDir = "regtest";
     }
 };
-static CBaseRegTestParams regTestParams;
 
-static CBaseChainParams* pCurrentBaseParams = 0;
+static std::unique_ptr<CBaseChainParams> globalChainBaseParams;
 
 const CBaseChainParams& BaseParams()
 {
-    assert(pCurrentBaseParams);
-    return *pCurrentBaseParams;
+    assert(globalChainBaseParams);
+    return *globalChainBaseParams;
 }
 
-CBaseChainParams& BaseParams(const std::string& chain)
+std::unique_ptr<CBaseChainParams> CreateBaseChainParams(const std::string& chain)
 {
     if (chain == CBaseChainParams::MAIN)
-        return mainParams;
+        return std::unique_ptr<CBaseChainParams>(new CBaseMainParams());
     else if (chain == CBaseChainParams::TESTNET)
-        return testNetParams;
+        return std::unique_ptr<CBaseChainParams>(new CBaseTestNetParams());
     else if (chain == CBaseChainParams::REGTEST)
-        return regTestParams;
+        return std::unique_ptr<CBaseChainParams>(new CBaseRegTestParams());
     else
         throw std::runtime_error(strprintf("%s: Unknown chain %s.", __func__, chain));
 }
 
 void SelectBaseParams(const std::string& chain)
 {
-    pCurrentBaseParams = &BaseParams(chain);
+    globalChainBaseParams = CreateBaseChainParams(chain);
 }
 
 std::string ChainNameFromCommandLine()
diff --git a/src/chainparamsbase.h b/src/chainparamsbase.h
index 84350cf65b..fc101f5b77 100644
--- a/src/chainparamsbase.h
+++ b/src/chainparamsbase.h
@@ -5,6 +5,7 @@
 #ifndef BITCOIN_CHAINPARAMSBASE_H
 #define BITCOIN_CHAINPARAMSBASE_H
 
+#include <memory>
 #include <string>
 #include <vector>
 
@@ -31,6 +32,13 @@ protected:
 };
 
 /**
+ * Creates and returns a std::unique_ptr<CBaseChainParams> of the chosen chain.
+ * @returns a CBaseChainParams* of the chosen chain.
+ * @throws a std::runtime_error if the chain is not supported.
+ */
+std::unique_ptr<CBaseChainParams> CreateBaseChainParams(const std::string& chain);
+
+/**
  * Append the help messages for the chainparams options to the
  * parameter string.
  */
@@ -42,8 +50,6 @@ void AppendParamsHelpMessages(std::string& strUsage, bool debugHelp=true);
  */
 const CBaseChainParams& BaseParams();
 
-CBaseChainParams& BaseParams(const std::string& chain);
-
 /** Sets the params returned by Params() to those for the given network. */
 void SelectBaseParams(const std::string& chain);
 
diff --git a/src/init.cpp b/src/init.cpp
index 266e1731eb..804c5941bf 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -328,6 +328,8 @@ void OnRPCPreCommand(const CRPCCommand& cmd)
 
 std::string HelpMessage(HelpMessageMode mode)
 {
+    const auto defaultBaseParams = CreateBaseChainParams(CBaseChainParams::MAIN);
+    const auto testnetBaseParams = CreateBaseChainParams(CBaseChainParams::TESTNET);
     const bool showDebug = GetBoolArg("-help-debug", false);
 
     // When adding new options to the categories, please keep and ensure alphabetical ordering.
@@ -500,7 +502,7 @@ std::string HelpMessage(HelpMessageMode mode)
     strUsage += HelpMessageOpt("-rpcuser=<user>", _("Username for JSON-RPC connections"));
     strUsage += HelpMessageOpt("-rpcpassword=<pw>", _("Password for JSON-RPC connections"));
     strUsage += HelpMessageOpt("-rpcauth=<userpw>", _("Username and hashed password for JSON-RPC connections. The field <userpw> comes in the format: <USERNAME>:<SALT>$<HASH>. A canonical python script is included in share/rpcuser. The client then connects normally using the rpcuser=<USERNAME>/rpcpassword=<PASSWORD> pair of arguments. This option can be specified multiple times"));
-    strUsage += HelpMessageOpt("-rpcport=<port>", strprintf(_("Listen for JSON-RPC connections on <port> (default: %u or testnet: %u)"), BaseParams(CBaseChainParams::MAIN).RPCPort(), BaseParams(CBaseChainParams::TESTNET).RPCPort()));
+    strUsage += HelpMessageOpt("-rpcport=<port>", strprintf(_("Listen for JSON-RPC connections on <port> (default: %u or testnet: %u)"), defaultBaseParams->RPCPort(), testnetBaseParams->RPCPort()));
     strUsage += HelpMessageOpt("-rpcallowip=<ip>", _("Allow JSON-RPC connections from specified source. Valid for <ip> are a single IP (e.g. 1.2.3.4), a network/netmask (e.g. 1.2.3.4/255.255.255.0) or a network/CIDR (e.g. 1.2.3.4/24). This option can be specified multiple times"));
     strUsage += HelpMessageOpt("-rpcserialversion", strprintf(_("Sets the serialization of raw transaction or block hex returned in non-verbose mode, non-segwit(0) or segwit(1) (default: %d)"), DEFAULT_RPC_SERIALIZE_VERSION));
     strUsage += HelpMessageOpt("-rpcthreads=<n>", strprintf(_("Set the number of threads to service RPC calls (default: %d)"), DEFAULT_HTTP_THREADS));
@@ -1123,7 +1125,7 @@ bool AppInitParameterInteraction()
             for (int j=0; j<(int)Consensus::MAX_VERSION_BITS_DEPLOYMENTS; ++j)
             {
                 if (vDeploymentParams[0].compare(VersionBitsDeploymentInfo[j].name) == 0) {
-                    UpdateRegtestBIP9Parameters(Consensus::DeploymentPos(j), nStartTime, nTimeout);
+                    UpdateBIP9Parameters(Consensus::DeploymentPos(j), nStartTime, nTimeout);
                     found = true;
                     LogPrintf("Setting BIP9 activation parameters for %s to start=%ld, timeout=%ld\n", vDeploymentParams[0], nStartTime, nTimeout);
                     break;