Fix Windows shutdown hang and register console ctrl handler

- Remove GenerateBitcoins(false) from stop RPC handler because it calls
  minerThreads->join_all() which blocks the RPC thread, preventing the
  response from being sent back to the client. Miners are already stopped
  in Shutdown() so this was redundant.
- Add ShutdownRequested() checks in miner peer-wait and nonce loops
- Register SetConsoleCtrlHandler on Windows for clean Ctrl+C/close
- Add check_and_clean_target for --linux-release builds

build.sh

@@ -43,6 +43,7 @@ fi
 
 # Check for --linux-release flag (builds inside Ubuntu 20.04 container for max compatibility)
 if [[ "${1:-}" == "--linux-release" ]]; then
+    check_and_clean_target "linux-docker"
     shift
     echo "Building Linux release inside Ubuntu 20.04 Docker container..."
     sudo docker build -t hush-builder -f Dockerfile.build .

src/init.cpp

@@ -1053,6 +1053,9 @@ bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler)
 
     // Ignore SIGPIPE, otherwise it will bring the daemon down if the client closes unexpectedly
     signal(SIGPIPE, SIG_IGN);
+#else
+    // On Windows, register console control handler for clean shutdown on Ctrl+C / window close
+    SetConsoleCtrlHandler(consoleCtrlHandler, true);
 #endif
 
     std::set_new_handler(new_handler_terminate);

src/miner.cpp

@@ -34,6 +34,7 @@
 #include "RandomX/src/randomx.h"
 #endif
 #include "hash.h"
+#include "init.h"
 #include "key_io.h"
 #include "main.h"
 #include "metrics.h"
@@ -1302,6 +1303,8 @@ void static RandomXMiner()
                     }
                     if (!fvNodesEmpty )//&& !IsInitialBlockDownload())
                         break;
+                    if (ShutdownRequested())
+                        throw boost::thread_interrupted();
                     MilliSleep(15000);
                     //fprintf(stderr,"fvNodesEmpty %d IsInitialBlockDownload(%s) %d\n",(int32_t)fvNodesEmpty,SMART_CHAIN_SYMBOL,(int32_t)IsInitialBlockDownload());
 
@@ -1570,6 +1573,8 @@ void static RandomXMiner()
                     }
 
                     boost::this_thread::interruption_point();
+                    if (ShutdownRequested())
+                        throw boost::thread_interrupted();
 
                     if (vNodes.empty() && chainparams.MiningRequiresPeers())
                     {
@@ -1702,6 +1707,8 @@ void static BitcoinMiner()
                     }
                     if (!fvNodesEmpty )//&& !IsInitialBlockDownload())
                         break;
+                    if (ShutdownRequested())
+                        throw boost::thread_interrupted();
                     MilliSleep(15000);
                     //fprintf(stderr,"fvNodesEmpty %d IsInitialBlockDownload(%s) %d\n",(int32_t)fvNodesEmpty,SMART_CHAIN_SYMBOL,(int32_t)IsInitialBlockDownload());
 

src/rpc/server.cpp

@@ -267,13 +267,9 @@ UniValue stop(const UniValue& params, bool fHelp, const CPubKey& mypk)
             "stop\n"
             "\nStop Hush server.");
 
-#ifdef ENABLE_WALLET
+    // Don't stop miners here — GenerateBitcoins(false) blocks on join_all()
-    GenerateBitcoins(false, pwalletMain, 0);
+    // which prevents the RPC response from being sent back to the client.
-#else
+    // Miners are stopped in Shutdown() instead.
-    GenerateBitcoins(false, 0);
-#endif
-
-    // Shutdown will take long enough that the response should get back
     StartShutdown();
 
     if ((strncmp(SMART_CHAIN_SYMBOL, "HUSH3", 5) == 0) ) {