Input: Further small changes to error handling

Calling Error() in an input reader now automatically will disable the
reader and return a failure in the Update/Heartbeat calls.

Also adds more tests.

Addresses BIT-1181

src/input/ReaderBackend.cc

@@ -306,11 +306,16 @@ bool ReaderBackend::Update()
 	if ( ! success )
 		DisableFrontend();
 
-	return success;
+	return !disabled; // always return failure if we have been disabled in the meantime
 	}
 
 void ReaderBackend::DisableFrontend()
 	{
+	// We might already have been disabled - e.g., due to a call to error. In that
+	// case, ignore this...
+	if ( disabled )
+		return;
+
 	// We also set disabled here, because there still may be other
 	// messages queued and we will dutifully ignore these from now.
 	disabled = true;
@@ -341,6 +346,9 @@ void ReaderBackend::Error(const char* msg)
 	{
 	SendOut(new ReaderErrorMessage(frontend, ReaderErrorMessage::ERROR, msg));
 	MsgThread::Error(msg);
+
+	// Force errors to be fatal.
+	DisableFrontend();
 	}
 
 }

src/input/ReaderBackend.h

@@ -191,6 +191,16 @@ public:
 
 	void Info(const char* msg) override;
 	void Warning(const char* msg) override;
+
+	/**
+	 * Reports an error in the child thread. For input readers, it is assumed,
+	 * that Info and Warnings do not cause the read operation to fail (they might
+	 * signal that, e.g., a single line was ignored).
+	 *
+	 * It is assumed that Errors are not recoverable. Calling the Error function
+	 * will return the error back to scriptland and also *automatically* causes
+	 * the current reader to be disabled and torn down.
+	 */
 	void Error(const char* msg) override;
 
 protected:

testing/btest/Baseline/scripts.base.frameworks.input.errors/.stderr

@@ -33,4 +33,9 @@ error: Input stream event6: Event has wrong number of arguments
 error: Input stream event7: Incompatible type for event in field 3. Need type 'int':int, got 'record':record { i:int; r:record { i:int; s:file of string; }; }
 error: Input stream event8: Incompatible type for event in field 5. Need type 'addr':addr, got 'string':string
 error: Input stream event9: Event has wrong number of arguments
+error: Input stream error1: Error event's first attribute must be of type Input::EventDescription
+error: Input stream error2: Error event's first attribute must be of type Input::TableDescription
+error: Input stream error3: Error event's first attribute must be of type Input::EventDescription
+error: Input stream error4: Error event's second attribute must be of type string
+error: Input stream error5: Error event's third attribute must be of type Reporter::Level
 received termination signal

testing/btest/Baseline/scripts.base.frameworks.input.invalidtext/.stderrwithoutfirstline

@@ -1,4 +1,6 @@
 warning: ../input.log/Input::READER_ASCII: String 'l' contained no parseable number
 warning: ../input.log/Input::READER_ASCII: Could not convert line '	l' to Val. Ignoring line.
+warning: ../input.log/Input::READER_ASCII: String 'l' contained no parseable number
+warning: ../input.log/Input::READER_ASCII: Could not convert line '	l' to Val. Ignoring line.
 received termination signal
 >>>

testing/btest/Baseline/scripts.base.frameworks.input.invalidtext/out

@@ -1,5 +1,8 @@
-Event, String 'l' contained no parseable number, Reporter::WARNING
-Event, Could not convert line '\x09l' to Val. Ignoring line., Reporter::WARNING
+TableErrorEvent, String 'l' contained no parseable number, Reporter::WARNING
+TableErrorEvent, Could not convert line '\x09l' to Val. Ignoring line., Reporter::WARNING
 {
 [] = [c=5]
 }
+EventErrorEvent, String 'l' contained no parseable number, Reporter::WARNING
+EventErrorEvent, Could not convert line '\x09l' to Val. Ignoring line., Reporter::WARNING
+Event, [c=5]

testing/btest/scripts/base/frameworks/input/errors.bro

@@ -118,6 +118,31 @@ event event10(description: Input::TableDescription, tpe: Input::Event, i: Idx, c
 	{
 	}
 
+# these are legit to test the error events
+event event11(description: Input::EventDescription, tpe: Input::Event, v: Val)
+	{
+	}
+
+event errorhandler1(desc: Input::TableDescription, msg: string, level: Reporter::Level)
+	{
+	}
+
+event errorhandler2(desc: Input::EventDescription, msg: string, level: Reporter::Level)
+	{
+	}
+
+event errorhandler3(desc: string, msg: string, level: Reporter::Level)
+	{
+	}
+
+event errorhandler4(desc: Input::EventDescription, msg: count, level: Reporter::Level)
+	{
+	}
+
+event errorhandler5(desc: Input::EventDescription, msg: string, level: count)
+	{
+	}
+
 event kill_me()
 	{
 	terminate();
@@ -157,5 +182,11 @@ event bro_init()
 	Input::add_event([$source="input.log", $name="event8", $fields=Val, $ev=event8, $want_record=F]);
 	Input::add_event([$source="input.log", $name="event9", $fields=Val, $ev=event9, $want_record=F]);
 
+	Input::add_event([$source="input.log", $name="error1", $fields=Val, $ev=event11, $want_record=T, $error_ev=errorhandler1]);
+	Input::add_table([$source="input.log", $name="error2", $idx=Idx, $val=Val, $destination=val_table, $error_ev=errorhandler2]);
+	Input::add_event([$source="input.log", $name="error3", $fields=Val, $ev=event11, $want_record=T, $error_ev=errorhandler3]);
+	Input::add_event([$source="input.log", $name="error4", $fields=Val, $ev=event11, $want_record=T, $error_ev=errorhandler4]);
+	Input::add_event([$source="input.log", $name="error5", $fields=Val, $ev=event11, $want_record=T, $error_ev=errorhandler5]);
+
 	schedule 3secs { kill_me() };
 	}

testing/btest/scripts/base/frameworks/input/invalidtext.bro

@@ -26,11 +26,23 @@ type Val: record {
 	c: count;
 };
 
+global endcount: count = 0;
+
 global servers: table[string] of Val = table();
 
 event handle_our_errors(desc: Input::TableDescription, msg: string, level: Reporter::Level)
 	{
-	print outfile, "Event", msg, level;
+	print outfile, "TableErrorEvent", msg, level;
+	}
+
+event handle_our_errors_event(desc: Input::EventDescription, msg: string, level: Reporter::Level)
+	{
+	print outfile, "EventErrorEvent", msg, level;
+	}
+
+event line(description: Input::EventDescription, tpe: Input::Event, v: Val)
+	{
+	print outfile, "Event", v;
 	}
 
 event bro_init()
@@ -38,11 +50,22 @@ event bro_init()
 	outfile = open("../out");
 	# first read in the old stuff into the table...
 	Input::add_table([$source="../input.log", $name="ssh", $error_ev=handle_our_errors, $idx=Idx, $val=Val, $destination=servers]);
+	Input::add_event([$source="../input.log", $name="sshevent", $error_ev=handle_our_errors_event, $fields=Val, $want_record=T, $ev=line]);
 	}
 
 event Input::end_of_data(name: string, source:string)
 	{
-	print outfile, servers;
-	Input::remove("ssh");
-	terminate();
+	++endcount;
+
+	if ( endcount == 1 )
+		{
+		print outfile, servers;
+		Input::remove("ssh");
+		}
+
+	if ( endcount == 2 )
+		{
+		Input::remove("sshevent");
+		terminate();
+		}
 	}