Package edu.berkeley.cs.jqf.fuzz.repro

Class ReproServerGuidance

java.lang.Object

edu.berkeley.cs.jqf.fuzz.repro.ReproServerGuidance

All Implemented Interfaces:

Guidance

public class ReproServerGuidance
extends Object
implements Guidance

Author:

Rohan Padhye

Field Summary

Fields

Modifier and Type	Field	Description
protected Coverage	coverage
protected File	coverageFile
protected File	inputFile
protected BufferedReader	inputFileNameReader
protected InputStream	inputFileStream

Constructor Summary

Constructors

Constructor	Description
ReproServerGuidance(String inPipe, String coverageFile)

Method Summary

Modifier and Type	Method	Description
Consumer<TraceEvent>	generateCallBack(Thread thread)	Returns a callback generator for a thread's event trace.
InputStream	getInput()	Returns a reference to a stream of values return from the pseudo-random number generator.
void	handleResult(Result result, Throwable error)	Handles the end of a fuzzing trial.
boolean	hasInput()	Returns whether an input is ready for a new trial to be executed.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface edu.berkeley.cs.jqf.fuzz.guidance.Guidance

observeGeneratedArgs, run

Field Detail

coverageFile

protected File coverageFile

inputFileNameReader

protected BufferedReader inputFileNameReader

inputFile

protected File inputFile

inputFileStream

protected InputStream inputFileStream

coverage

protected Coverage coverage

Constructor Detail

ReproServerGuidance

public ReproServerGuidance(String inPipe,
                           String coverageFile)
                    throws IOException

Throws:

IOException

Method Detail

hasInput

public boolean hasInput()

Description copied from interface: Guidance

Returns whether an input is ready for a new trial to be executed.

This method may block until a new input stream is made ready. If this method returns false, then JQF stops fuzzing and this guidance will not be used further.

Specified by:

hasInput in interface Guidance

Returns:

whether a new trial should be executed

getInput

public InputStream getInput()
                     throws IllegalStateException,
                            GuidanceException

Description copied from interface: Guidance

Returns a reference to a stream of values return from the pseudo-random number generator.

This method is guaranteed to be invoked by JQF at most once after each invocation of Guidance.hasInput() that has returned true.

If Guidance.hasInput() returns false or has not been invoked since the last call to Guidance.getInput(), then invoking this method may throw an IllegalStateException.

Specified by:

getInput in interface Guidance

Returns:

a stream of bytes to be used by the input generator(s)

Throws:

IllegalStateException - if the last Guidance.hasInput() returned false

GuidanceException - if there was an I/O or other error in generating the input stream

handleResult

public void handleResult(Result result,
                         Throwable error)

Description copied from interface: Guidance

Handles the end of a fuzzing trial.

This method is guaranteed to be invoked by JQF exactly once after each invocation of Guidance.getInput(). Therefore, it is safe to open resources such as files in a call to Guidance.getInput() and only close them inside this method.

If result is SUCCESS, then error is either null or it is an instance of a throwable that is declared by the test method in its throws clause.

If result is INVALID, then error is either an AssumptionViolatedException, if the argument of an assume() statement was false, or it is a GuidanceException, indicating that fuzzing was interrupted during the execution of this trial (and will not continue further).

If result is FAILURE, then error is some other throwable that was thrown by the test execution but was not listed in its throws clause. This is the only way to detect test errors. Assertion errors will typically fall into this category. So will other unlisted RuntimeExceptions such as NPE.

Specified by:

handleResult in interface Guidance

Parameters:

result - the result of the fuzzing trial

error - the error thrown during the trial, or null

generateCallBack

public Consumer<TraceEvent> generateCallBack(Thread thread)

Description copied from interface: Guidance

Returns a callback generator for a thread's event trace.

The application under test is instrumented such that each thread generates a sequence of TraceEvents that may be handled by a separate callback method (though it may also be the same callback).

The callback provided by this method will typically be used for collection execution information such as branch coverage, which in turn is used for constructing the next input stream.

This method is a supplier of event consumers. It is invoked once per new application thread spawned during fuzzing.

Specified by:

generateCallBack in interface Guidance

Parameters:

thread - the thread whose events to handle

Returns:

a callback that handles trace events generated by that thread