(svn r21311) -Fix [FS#4260]: AIs in an infinite loop in e.g. autosave, but also getting settings and such from info.nut, would not be interrupted after a while causing OpenTTD to seem to not respond

4 files changed, 35 insertions, 22 deletions

diff --git a/src/ai/ai_info.cpp b/src/ai/ai_info.cpp
index 54725cd48..2194f20c5 100644
--- a/src/ai/ai_info.cpp
+++ b/src/ai/ai_info.cpp
@@ -19,6 +19,9 @@
 #include "../debug.h"
 #include "../rev.h"
 
+/** Maximum number of operations allowed for getting a particular setting. */
+static const int MAX_GET_SETTING_OPS = 100000;
+
 /** Configuration for AI start date, every AI has this setting. */
 AIConfigItem _start_date_config = {
 	"start_date",
@@ -78,19 +81,19 @@ static bool CheckAPIVersion(const char *api_version)
 		if (!info->GetSettings()) return SQ_ERROR;
 	}
 	if (info->engine->MethodExists(*info->SQ_instance, "MinVersionToLoad")) {
-		if (!info->engine->CallIntegerMethod(*info->SQ_instance, "MinVersionToLoad", &info->min_loadable_version)) return SQ_ERROR;
+		if (!info->engine->CallIntegerMethod(*info->SQ_instance, "MinVersionToLoad", &info->min_loadable_version, MAX_GET_SETTING_OPS)) return SQ_ERROR;
 	} else {
 		info->min_loadable_version = info->GetVersion();
 	}
 	/* When there is an UseAsRandomAI function, call it. */
 	if (info->engine->MethodExists(*info->SQ_instance, "UseAsRandomAI")) {
-		if (!info->engine->CallBoolMethod(*info->SQ_instance, "UseAsRandomAI", &info->use_as_random)) return SQ_ERROR;
+		if (!info->engine->CallBoolMethod(*info->SQ_instance, "UseAsRandomAI", &info->use_as_random, MAX_GET_SETTING_OPS)) return SQ_ERROR;
 	} else {
 		info->use_as_random = true;
 	}
 	/* Try to get the API version the AI is written for. */
 	if (info->engine->MethodExists(*info->SQ_instance, "GetAPIVersion")) {
-		if (!info->engine->CallStringMethodStrdup(*info->SQ_instance, "GetAPIVersion", &info->api_version)) return SQ_ERROR;
+		if (!info->engine->CallStringMethodStrdup(*info->SQ_instance, "GetAPIVersion", &info->api_version, MAX_GET_SETTING_OPS)) return SQ_ERROR;
 		if (!CheckAPIVersion(info->api_version)) {
 			DEBUG(ai, 1, "Loading info.nut from (%s.%d): GetAPIVersion returned invalid version", info->GetName(), info->GetVersion());
 			return SQ_ERROR;
@@ -130,7 +133,7 @@ static bool CheckAPIVersion(const char *api_version)
 
 bool AIInfo::GetSettings()
 {
-	return this->engine->CallMethod(*this->SQ_instance, "GetSettings", NULL, -1);
+	return this->engine->CallMethod(*this->SQ_instance, "GetSettings", NULL, MAX_GET_SETTING_OPS);
 }
 
 AIInfo::AIInfo() :
@@ -360,7 +363,7 @@ int AIInfo::GetSettingDefaultValue(const char *name) const
 	}
 
 	/* Cache the category */
-	if (!library->CheckMethod("GetCategory") || !library->engine->CallStringMethodStrdup(*library->SQ_instance, "GetCategory", &library->category)) {
+	if (!library->CheckMethod("GetCategory") || !library->engine->CallStringMethodStrdup(*library->SQ_instance, "GetCategory", &library->category, MAX_GET_SETTING_OPS)) {
 		delete library;
 		return SQ_ERROR;
 	}
diff --git a/src/ai/ai_instance.cpp b/src/ai/ai_instance.cpp
index 80cc06a7f..628a32e29 100644
--- a/src/ai/ai_instance.cpp
+++ b/src/ai/ai_instance.cpp
@@ -76,6 +76,11 @@
 #include "../company_base.h"
 #include "../fileio_func.h"
 
+/** The maximum number of operations for saving or loading the data of an AI. */
+static const int MAX_SL_OPS          = 100000;
+/** The maximum number of operations for initial start of an AI. */
+static const int MAX_CONSTRUCTOR_OPS = 100000;
+
 AIStorage::~AIStorage()
 {
 	/* Free our pointers */
@@ -344,7 +349,7 @@ void AIInstance::GameLoop()
 			AIObject::SetAllowDoCommand(false);
 			/* Run the constructor if it exists. Don't allow any DoCommands in it. */
 			if (this->engine->MethodExists(*this->instance, "constructor")) {
-				if (!this->engine->CallMethod(*this->instance, "constructor", 100000) || this->engine->IsSuspended()) {
+				if (!this->engine->CallMethod(*this->instance, "constructor", MAX_CONSTRUCTOR_OPS) || this->engine->IsSuspended()) {
 					if (this->engine->IsSuspended()) AILog::Error("This AI took too long to initialize. AI is not started.");
 					this->Died();
 					return;
@@ -611,7 +616,7 @@ void AIInstance::Save()
 		bool backup_allow = AIObject::GetAllowDoCommand();
 		AIObject::SetAllowDoCommand(false);
 		try {
-			if (!this->engine->CallMethod(*this->instance, "Save", &savedata)) {
+			if (!this->engine->CallMethod(*this->instance, "Save", &savedata, MAX_SL_OPS)) {
 				/* The script crashed in the Save function. We can't kill
 				 * it here, but do so in the next AI tick. */
 				SaveEmpty();
@@ -634,7 +639,7 @@ void AIInstance::Save()
 		AIObject::SetAllowDoCommand(backup_allow);
 
 		if (!sq_istable(savedata)) {
-			AILog::Error("Save function should return a table.");
+			AILog::Error(this->engine->IsSuspended() ? "This AI took too long to Save." : "Save function should return a table.");
 			SaveEmpty();
 			this->engine->CrashOccurred();
 			return;
@@ -776,7 +781,7 @@ bool AIInstance::CallLoad()
 
 	/* Call the AI load function. sq_call removes the arguments (but not the
 	 * function pointer) from the stack. */
-	if (SQ_FAILED(sq_call(vm, 3, SQFalse, SQFalse, 100000))) return false;
+	if (SQ_FAILED(sq_call(vm, 3, SQFalse, SQFalse, MAX_SL_OPS))) return false;
 
 	/* Pop 1) The version, 2) the savegame data, 3) the object instance, 4) the function pointer. */
 	sq_pop(vm, 4);
diff --git a/src/script/script_info.cpp b/src/script/script_info.cpp
index 807c42bc1..152bb02f3 100644
--- a/src/script/script_info.cpp
+++ b/src/script/script_info.cpp
@@ -16,6 +16,11 @@
 #include "script_info.hpp"
 #include "script_scanner.hpp"
 
+/** Number of operations to get the author and similar information. */
+static const int MAX_GET_OPS            =   1000;
+/** Number of operations to create an instance of an AI. */
+static const int MAX_CREATEINSTANCE_OPS = 100000;
+
 ScriptFileInfo::~ScriptFileInfo()
 {
 	free((void *)this->author);
@@ -66,17 +71,17 @@ bool ScriptFileInfo::CheckMethod(const char *name) const
 	info->main_script = strdup(scanner->GetMainScript());
 
 	/* Cache the data the info file gives us. */
-	if (!info->engine->CallStringMethodStrdup(*info->SQ_instance, "GetAuthor", &info->author)) return SQ_ERROR;
-	if (!info->engine->CallStringMethodStrdup(*info->SQ_instance, "GetName", &info->name)) return SQ_ERROR;
-	if (!info->engine->CallStringMethodStrdup(*info->SQ_instance, "GetShortName", &info->short_name)) return SQ_ERROR;
-	if (!info->engine->CallStringMethodStrdup(*info->SQ_instance, "GetDescription", &info->description)) return SQ_ERROR;
-	if (!info->engine->CallStringMethodStrdup(*info->SQ_instance, "GetDate", &info->date)) return SQ_ERROR;
-	if (!info->engine->CallIntegerMethod(*info->SQ_instance, "GetVersion", &info->version)) return SQ_ERROR;
-	if (!info->engine->CallStringMethodStrdup(*info->SQ_instance, "CreateInstance", &info->instance_name)) return SQ_ERROR;
+	if (!info->engine->CallStringMethodStrdup(*info->SQ_instance, "GetAuthor", &info->author, MAX_GET_OPS)) return SQ_ERROR;
+	if (!info->engine->CallStringMethodStrdup(*info->SQ_instance, "GetName", &info->name, MAX_GET_OPS)) return SQ_ERROR;
+	if (!info->engine->CallStringMethodStrdup(*info->SQ_instance, "GetShortName", &info->short_name, MAX_GET_OPS)) return SQ_ERROR;
+	if (!info->engine->CallStringMethodStrdup(*info->SQ_instance, "GetDescription", &info->description, MAX_GET_OPS)) return SQ_ERROR;
+	if (!info->engine->CallStringMethodStrdup(*info->SQ_instance, "GetDate", &info->date, MAX_GET_OPS)) return SQ_ERROR;
+	if (!info->engine->CallIntegerMethod(*info->SQ_instance, "GetVersion", &info->version, MAX_GET_OPS)) return SQ_ERROR;
+	if (!info->engine->CallStringMethodStrdup(*info->SQ_instance, "CreateInstance", &info->instance_name, MAX_CREATEINSTANCE_OPS)) return SQ_ERROR;
 
 	/* The GetURL function is optional. */
 	if (info->engine->MethodExists(*info->SQ_instance, "GetURL")) {
-		if (!info->engine->CallStringMethodStrdup(*info->SQ_instance, "GetURL", &info->url)) return SQ_ERROR;
+		if (!info->engine->CallStringMethodStrdup(*info->SQ_instance, "GetURL", &info->url, MAX_GET_OPS)) return SQ_ERROR;
 	}
 
 	return 0;
diff --git a/src/script/squirrel.hpp b/src/script/squirrel.hpp
index 53a74eaaa..d50dc356a 100644
--- a/src/script/squirrel.hpp
+++ b/src/script/squirrel.hpp
@@ -140,11 +140,11 @@ public:
 	 * Call a method of an instance, in various flavors.
 	 * @return False if the script crashed or returned a wrong type.
 	 */
-	bool CallMethod(HSQOBJECT instance, const char *method_name, HSQOBJECT *ret, int suspend = -1);
-	bool CallMethod(HSQOBJECT instance, const char *method_name, int suspend = -1) { return this->CallMethod(instance, method_name, NULL, suspend); }
-	bool CallStringMethodStrdup(HSQOBJECT instance, const char *method_name, const char **res, int suspend = -1);
-	bool CallIntegerMethod(HSQOBJECT instance, const char *method_name, int *res, int suspend = -1);
-	bool CallBoolMethod(HSQOBJECT instance, const char *method_name, bool *res, int suspend = -1);
+	bool CallMethod(HSQOBJECT instance, const char *method_name, HSQOBJECT *ret, int suspend);
+	bool CallMethod(HSQOBJECT instance, const char *method_name, int suspend) { return this->CallMethod(instance, method_name, NULL, suspend); }
+	bool CallStringMethodStrdup(HSQOBJECT instance, const char *method_name, const char **res, int suspend);
+	bool CallIntegerMethod(HSQOBJECT instance, const char *method_name, int *res, int suspend);
+	bool CallBoolMethod(HSQOBJECT instance, const char *method_name, bool *res, int suspend);
 
 	/**
 	 * Check if a method exists in an instance.