(svn r17517) [0.7] -Backport from trunk:

- Fix: [Squirrel] In some cases the call stack would not be cleaned up properly during crash handling. Occasionally this causes asserts to be triggered or crashes [FS#3189] (r17515)
- Fix: When loading GRFConfigs from ini file, validate them wrt. duplicate GRF IDs [FS#3197] (r17510)
- Fix: When building a part fails during cloning, sell what was already cloned instead of leaving it "for free". Also make cloning multiheaded trains possible with with "max - 1" vehicles existing [FS#3196] (r17509)
- Fix: The wrong value was restored to SetAllowDoCommand possible resulting in an AI that was not allowed to do any actions (r17500)

src/3rdparty/squirrel/squirrel/sqvm.cpp

@@ -1142,6 +1142,8 @@ bool SQVM::CallNative(SQNativeClosure *nclosure,SQInteger nargs,SQInteger stackb
 	}
 
 
+	/* Store the call stack size, so we can restore that */
+	SQInteger cstksize = _callsstacksize;
 	SQInteger ret;
 	try {
 		SQBool can_suspend = this->_can_suspend;
@@ -1152,6 +1154,7 @@ bool SQVM::CallNative(SQNativeClosure *nclosure,SQInteger nargs,SQInteger stackb
 		_nnativecalls--;
 		suspend = false;
 
+		_callsstacksize = cstksize;
 		_stackbase = oldstackbase;
 		_top = oldtop;
 
@@ -1161,6 +1164,8 @@ bool SQVM::CallNative(SQNativeClosure *nclosure,SQInteger nargs,SQInteger stackb
 		throw;
 	}
 
+	assert(cstksize == _callsstacksize);
+
 	_nnativecalls--;
 	suspend = false;
 	if( ret == SQ_SUSPEND_FLAG) suspend = true;

src/ai/api/ai_controller.cpp

@@ -23,7 +23,7 @@
 
 /* static */ void AIController::Sleep(int ticks)
 {
-	if (!AIObject::GetAllowDoCommand()) {
+	if (!AIObject::CanSuspend()) {
 		throw AI_FatalError("You are not allowed to call Sleep in your constructor, Save(), Load(), and any valuator.");
 	}
 

src/ai/api/ai_object.cpp

@@ -161,6 +161,11 @@ void AIObject::SetAllowDoCommand(bool allow)
 }
 
 bool AIObject::GetAllowDoCommand()
+{
+	return GetStorage()->allow_do_command;
+}
+
+bool AIObject::CanSuspend()
 {
 	Squirrel *squirrel = GetCompany(_current_company)->ai_instance->engine;
 	return GetStorage()->allow_do_command && squirrel->CanSuspend();
@@ -189,7 +194,7 @@ int AIObject::GetCallbackVariable(int index)
 
 bool AIObject::DoCommand(TileIndex tile, uint32 p1, uint32 p2, uint cmd, const char *text, AISuspendCallbackProc *callback)
 {
-	if (AIObject::GetAllowDoCommand() == false) {
+	if (!AIObject::CanSuspend()) {
 		throw AI_FatalError("You are not allowed to execute any DoCommand (even indirect) in your constructor, Save(), Load(), and any valuator.");
 	}
 

src/ai/api/ai_object.hpp

@@ -133,8 +133,15 @@ protected:
 	static GroupID GetNewGroupID();
 
 	/**
-	 * Get the latest stored allow_do_command.
-	 *  If this is false, you are not allowed to do any DoCommands.
+	 * Can we suspend the AI at this moment?
+	 */
+	static bool CanSuspend();
+
+	/**
+	 * Get the internal value of allow_do_command. This can differ
+	 * from CanSuspend() if the reason we are not allowed
+	 * to execute a DoCommand is in squirrel and not the API.
+	 * In that case use this function to restore the previous value.
 	 */
 	static bool GetAllowDoCommand();
 

src/settings.cpp

@@ -1799,6 +1799,20 @@ static GRFConfig *GRFLoadConfig(IniFile *ini, const char *grpname, bool is_stati
 			continue;
 		}
 
+		/* Check for duplicate GRFID (will also check for duplicate filenames) */
+		bool duplicate = false;
+		for (const GRFConfig *gc = first; gc != NULL; gc = gc->next) {
+			if (gc->grfid == c->grfid) {
+				ShowInfoF("ini: ignoring  NewGRF '%s': duplicate GRF ID with '%s'", item->name, gc->filename);
+				duplicate = true;
+				break;
+			}
+		}
+		if (duplicate) {
+			ClearGRFConfig(&c);
+			continue;
+		}
+
 		/* Mark file as static to avoid saving in savegame. */
 		if (is_static) SetBit(c->flags, GCF_STATIC);
 

src/vehicle_cmd.cpp

@@ -374,10 +374,23 @@ CommandCost CmdCloneVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint
 			continue;
 		}
 
-		CommandCost cost = DoCommand(tile, v->engine_type, build_argument, flags, GetCmdBuildVeh(v));
+		/* In case we're building a multi headed vehicle and the maximum number of
+		 * vehicles is almost reached (e.g. max trains - 1) not all vehicles would
+		 * be cloned. When the non-primary engines were build they were seen as
+		 * 'new' vehicles whereas they would immediately be joined with a primary
+		 * engine. This caused the vehicle to be not build as 'the limit' had been
+		 * reached, resulting in partially build vehicles and such. */
+		DoCommandFlag build_flags = flags;
+		if ((flags & DC_EXEC) && !v->IsPrimaryVehicle()) build_flags |= DC_AUTOREPLACE;
+
+		CommandCost cost = DoCommand(tile, v->engine_type, build_argument, build_flags, GetCmdBuildVeh(v));
 		build_argument = 3; // ensure that we only assign a number to the first engine
 
-		if (CmdFailed(cost)) return cost;
+		if (CmdFailed(cost)) {
+			/* Can't build a part, then sell the stuff we already made; clear up the mess */
+			if (w_front != NULL) DoCommand(w_front->tile, w_front->index, 1, flags, GetCmdSellVeh(w_front));
+			return cost;
+		}
 
 		total_cost.AddCost(cost);