GenericExperiment: limit output logger buffer

Limit the serial-output logger buffer to prevent overly large memory
consumption in case the target system ends up, e.g., in an endless loop.
The buffer is limited to (golden-run output size)+1 to be able to detect
the case when the target system makes a correct output but faultily adds
extra characters afterwards.

Change-Id: I50c082f8fb09a702d87ab83732ca3e3463c46597

src/experiments/generic-experiment/experiment.cc

@@ -176,6 +176,14 @@ bool GenericExperiment::cb_start_experiment() {
 		m_log << "enabled logging on port E9 for SDC-detection" << std::endl;
 		enabled_e9_sol = true;
 		e9_file = std::string(cmd[E9_FILE].first()->arg);
+		e9_goldenrun = loadFile(e9_file);
+
+		// Limit the serial-output logger buffer to prevent overly large memory
+		// consumption in case the target system ends up, e.g., in an endless
+		// loop.  "+ 1" to be able to detect the case when the target system
+		// makes a correct output but faultily adds extra characters
+		// afterwards.
+		e9_sol.setLimit(e9_goldenrun.size() + 1);
 	}
 
 	if (cmd[WRITE_MEM_TEXT]) {
@@ -290,7 +298,6 @@ void GenericExperiment::cb_after_resume(fail::BaseListener *event) {
 		// check experiment's data for SDC
 		if (enabled_e9_sol) {
 			// compare golden run to experiment
-			std::vector<char> e9_goldenrun = loadFile(e9_file);
 			std::string e9_experiment = e9_sol.getOutput();
 			if ( ! (e9_experiment.size() == e9_goldenrun.size()
 					&& equal(e9_experiment.begin(), e9_experiment.end(), e9_goldenrun.begin())) ) {

src/experiments/generic-experiment/experiment.hpp

@@ -23,6 +23,7 @@ class GenericExperiment : public fail::DatabaseExperiment {
 	bool enabled_e9_sol;
 	std::string e9_file;
 	SerialOutputLogger e9_sol;
+	std::vector<char> e9_goldenrun;
 
 	bool enabled_mem_text;
 	fail::MemAccessListener l_mem_text;

src/plugins/serialoutput/SerialOutputLogger.hpp

@@ -40,6 +40,11 @@ public:
 	 * Returns the output variable.
 	 */
 	std::string getOutput();
+	/**
+	 * Sets the character limit.  Does not truncate the stored data if it
+	 * already exceeds the new limit.  0 = unlimited.
+	 */
+	void setLimit(unsigned char_limit) { m_limit = char_limit; }
 };
 
 #endif // __SERIAL_OUTPUT_LOGGER_HPP__