[wallet] Use global g_wallet_init_interface to init/destroy the wallet.

This commit creates a global g_wallet_init_interface, which is created
in bitcoind and bitcoin-qt. g_wallet_init_interface is used to init
and destroy the wallet.

This removes the dependency from init.cpp on the wallet library.

src/init.cpp

@@ -43,10 +43,8 @@
 #include <util.h>
 #include <utilmoneystr.h>
 #include <validationinterface.h>
-#ifdef ENABLE_WALLET
-#include <wallet/init.h>
-#endif
 #include <warnings.h>
+#include <walletinitinterface.h>
 #include <stdint.h>
 #include <stdio.h>
 #include <memory>
@@ -74,6 +72,7 @@ static const bool DEFAULT_STOPAFTERBLOCKIMPORT = false;
 
 std::unique_ptr<CConnman> g_connman;
 std::unique_ptr<PeerLogicValidation> peerLogic;
+std::unique_ptr<WalletInitInterface> g_wallet_init_interface;
 
 #if ENABLE_ZMQ
 static CZMQNotificationInterface* pzmqNotificationInterface = nullptr;
@@ -189,9 +188,9 @@ void Shutdown()
     StopREST();
     StopRPC();
     StopHTTPServer();
-#ifdef ENABLE_WALLET
-    WalletInit::Flush();
-#endif
+    if (g_wallet_init_interface) {
+        g_wallet_init_interface->Flush();
+    }
     StopMapPort();
 
     // Because these depend on each-other, we make sure that neither can be
@@ -249,9 +248,9 @@ void Shutdown()
         pcoinsdbview.reset();
         pblocktree.reset();
     }
-#ifdef ENABLE_WALLET
-    WalletInit::Stop();
-#endif
+    if (g_wallet_init_interface) {
+        g_wallet_init_interface->Stop();
+    }
 
 #if ENABLE_ZMQ
     if (pzmqNotificationInterface) {
@@ -271,9 +270,10 @@ void Shutdown()
     UnregisterAllValidationInterfaces();
     GetMainSignals().UnregisterBackgroundSignalScheduler();
     GetMainSignals().UnregisterWithMempoolSignals(mempool);
-#ifdef ENABLE_WALLET
-    WalletInit::Close();
-#endif
+    if (g_wallet_init_interface) {
+        g_wallet_init_interface->Close();
+    }
+    g_wallet_init_interface.reset();
     globalVerifyHandle.reset();
     ECC_Stop();
     LogPrintf("%s: done\n", __func__);
@@ -415,9 +415,9 @@ std::string HelpMessage(HelpMessageMode mode)
     strUsage += HelpMessageOpt("-whitelist=<IP address or network>", _("Whitelist peers connecting from the given IP address (e.g. 1.2.3.4) or CIDR notated network (e.g. 1.2.3.0/24). Can be specified multiple times.") +
         " " + _("Whitelisted peers cannot be DoS banned and their transactions are always relayed, even if they are already in the mempool, useful e.g. for a gateway"));
 
-#ifdef ENABLE_WALLET
-    strUsage += WalletInit::GetHelpString(showDebug);
-#endif
+    if (g_wallet_init_interface) {
+        strUsage += g_wallet_init_interface->GetHelpString(showDebug);
+    }
 
 #if ENABLE_ZMQ
     strUsage += HelpMessageGroup(_("ZeroMQ notification options:"));
@@ -1091,9 +1091,7 @@ bool AppInitParameterInteraction()
         return InitError(strprintf("acceptnonstdtxn is not currently supported for %s chain", chainparams.NetworkIDString()));
     nBytesPerSigOp = gArgs.GetArg("-bytespersigop", nBytesPerSigOp);
 
-#ifdef ENABLE_WALLET
-    if (!WalletInit::ParameterInteraction()) return false;
-#endif
+    if (g_wallet_init_interface && !g_wallet_init_interface->ParameterInteraction()) return false;
 
     fIsBareMultisigStd = gArgs.GetBoolArg("-permitbaremultisig", DEFAULT_PERMIT_BAREMULTISIG);
     fAcceptDatacarrier = gArgs.GetBoolArg("-datacarrier", DEFAULT_ACCEPT_DATACARRIER);
@@ -1256,9 +1254,9 @@ bool AppInitMain()
      * available in the GUI RPC console even if external calls are disabled.
      */
     RegisterAllCoreRPCCommands(tableRPC);
-#ifdef ENABLE_WALLET
-    WalletInit::RegisterRPC(tableRPC);
-#endif
+    if (g_wallet_init_interface) {
+        g_wallet_init_interface->RegisterRPC(tableRPC);
+    }
 
     /* Start the RPC server already.  It will be started in "warmup" mode
      * and not really process calls already (but it will signify connections
@@ -1275,9 +1273,8 @@ bool AppInitMain()
     int64_t nStart;
 
     // ********************************************************* Step 5: verify wallet database integrity
-#ifdef ENABLE_WALLET
-    if (!WalletInit::Verify()) return false;
-#endif
+    if (g_wallet_init_interface && !g_wallet_init_interface->Verify()) return false;
+
     // ********************************************************* Step 6: network initialization
     // Note that we absolutely cannot open any actual connections
     // until the very end ("start node") as the UTXO/block state
@@ -1595,11 +1592,7 @@ bool AppInitMain()
     fFeeEstimatesInitialized = true;
 
     // ********************************************************* Step 8: load wallet
-#ifdef ENABLE_WALLET
-    if (!WalletInit::Open()) return false;
-#else
-    LogPrintf("No wallet support compiled in!\n");
-#endif
+    if (g_wallet_init_interface && !g_wallet_init_interface->Open()) return false;
 
     // ********************************************************* Step 9: data directory maintenance
 
@@ -1745,9 +1738,9 @@ bool AppInitMain()
     SetRPCWarmupFinished();
     uiInterface.InitMessage(_("Done loading"));
 
-#ifdef ENABLE_WALLET
-    WalletInit::Start(scheduler);
-#endif
+    if (g_wallet_init_interface) {
+        g_wallet_init_interface->Start(scheduler);
+    }
 
     return true;
 }