fix(Apps/SOAP): prevent shutdown deadlock on in-flight commands (#26335)

Co-authored-by: blinkysc <blinkysc@users.noreply.github.com>

src/server/apps/worldserver/ACSoap/ACSoap.cpp

@@ -20,6 +20,8 @@
 #include "Log.h"
 #include "World.h"
 #include "soapStub.h"
+#include <chrono>
+#include <memory>
 
 void ACSoapThread(const std::string& host, uint16 port)
 {
@@ -108,21 +110,28 @@ int ns1__executeCommand(soap* soap, char* command, char** result)
         return soap_sender_fault(soap, "Command can not be empty", "The supplied command was an empty string");
 
     LOG_DEBUG("network.soap", "ACSoap: got command '{}'", command);
-    SOAPCommand connection;
+
+    // Shared so the object survives if we stop waiting below: the queued command keeps a raw
+    // pointer to it and the world thread may still run it after that. The extra reference is
+    // released by commandFinished() once the world side is done with it.
+    auto connection = std::make_shared<SOAPCommand>();
+    connection->m_self = connection;
 
     // commands are executed in the world thread. We have to wait for them to be completed
+    sWorld->QueueCliCommand(new CliCommandHolder(connection.get(), command, &SOAPCommand::print, &SOAPCommand::commandFinished));
+
+    // Wait for the command to finish, but bail on shutdown: ProcessCliCommands() (which fulfils
+    // the promise) stops once the world loop exits, so an unbounded wait here would deadlock.
+    std::future<void> finished = connection->finishedPromise.get_future();
+    while (finished.wait_for(std::chrono::seconds(1)) != std::future_status::ready)
     {
-        // CliCommandHolder will be deleted from world, accessing after queueing is NOT save
+        if (World::IsStopped())
-        CliCommandHolder* cmd = new CliCommandHolder(&connection, command, &SOAPCommand::print, &SOAPCommand::commandFinished);
+            return soap_receiver_fault(soap, "Server is shutting down", "Command aborted: the server is shutting down");
-        sWorld->QueueCliCommand(cmd);
     }
 
-    // Wait until the command has finished executing
-    connection.finishedPromise.get_future().wait();
-
     // The command has finished executing already
-    char* printBuffer = soap_strdup(soap, connection.m_printBuffer.c_str());
+    char* printBuffer = soap_strdup(soap, connection->m_printBuffer.c_str());
-    if (connection.hasCommandSucceeded())
+    if (connection->hasCommandSucceeded())
     {
         *result = printBuffer;
         return SOAP_OK;
@@ -135,6 +144,8 @@ void SOAPCommand::commandFinished(void* soapconnection, bool success)
 {
     SOAPCommand* con = (SOAPCommand*)soapconnection;
     con->setCommandSuccess(success);
+    // world side is done with us; drop the keep-alive (may free the object)
+    con->m_self.reset();
 }
 
 ////////////////////////////////////////////////////////////////////////////////

src/server/apps/worldserver/ACSoap/ACSoap.h

@@ -20,6 +20,7 @@
 
 #include "Define.h"
 #include <future>
+#include <memory>
 
 void process_message(struct soap* soap_message);
 void ACSoapThread(const std::string& host, uint16 port);
@@ -58,6 +59,8 @@ public:
     bool m_success;
     std::string m_printBuffer;
     std::promise<void> finishedPromise;
+    // keep-alive while a queued command still references this object; released in commandFinished()
+    std::shared_ptr<SOAPCommand> m_self;
 };
 
 #endif