dk.brics.tajs.monitoring

Class Monitoring<BlockStateType extends BlockState<BlockStateType,CallContextType,CallEdgeType>,CallContextType extends ICallContext<CallContextType>,CallEdgeType extends CallEdge<BlockStateType>>

java.lang.Object

dk.brics.tajs.monitoring.Monitoring<BlockStateType,CallContextType,CallEdgeType>

All Implemented Interfaces:

IMonitoring<BlockStateType,CallContextType>

public class Monitoring<BlockStateType extends BlockState<BlockStateType,CallContextType,CallEdgeType>,CallContextType extends ICallContext<CallContextType>,CallEdgeType extends CallEdge<BlockStateType>>
extends Object
implements IMonitoring<BlockStateType,CallContextType>

Records various information during the scan phase of an analysis.

Constructor Summary

Constructors

Constructor and Description
Monitoring() Constructs a new monitoring object.

Method Summary

Methods

Modifier and Type	Method and Description
void	addMessage(AbstractNode n, Message.Severity severity, String msg) Adds a message for the given node.
void	addMessage(AbstractNode n, Message.Severity severity, String key, String msg) Adds a message for the given node.
void	addMessageInfo(AbstractNode n, Message.Severity severity, String msg) Adds a message for the given node.
void	beginScanPhase(FlowGraph fg) Initializes messages.
List<Message>	endScanPhase(FlowGraph fg) Finalizes messages by adding messages about unreachable code/functions, unused variables and parameters, dead assignments, and shadowing declarations.
void	generateUnreachableMap() Produces output showing the parts of the code that is determined unreachable by the analysis.
Set<Message>	getMessages() Returns the collected messages.
Set<AbstractNode>	getReachableNodes() Returns the set of maybe reachable nodes.
int	getTotalNumberOfNodeTransfers() Returns the total number of node transfers.
Map<TypeCollector.VariableSummary,Value>	getTypeInformation() Returns the collected type information.
void	presentTypeInformation() Presents the collected type information.
void	reportShadowing(FlowGraph fg) Add messages about shadowing.
String	toString() Returns a string description of the results.
void	visitBlockTransfer() Registers a block transfer occurrence.
void	visitCall(AbstractNode n, boolean maybe_non_function, boolean maybe_function) Registers a potential call/construct to a non-function value.
void	visitEvalCall(AbstractNode n, Value v) Registers a call to eval.
void	visitFunction(Function f, Collection<BlockStateType> entry_states) Registers the function and checks whether it is unreachable.
void	visitIf(IfNode n, Value v) Checks whether the branch condition is always true or always false.
void	visitIn(AbstractNode n, boolean maybe_v2_object, boolean maybe_v2_nonobject) Checks whether the 'in' operation may fail.
void	visitInnerHTMLWrite(Node n, Value v) Registers a write to innerHTML.
void	visitInstanceof(AbstractNode n, boolean maybe_v2_non_function, boolean maybe_v2_function, boolean maybe_v2_prototype_primitive, boolean maybe_v2_prototype_nonprimitive) Checks whether the 'instanceof' operation may fail.
void	visitJoin() Registers a state join operation.
void	visitNativeFunctionCall(AbstractNode n, HostObject hostobject, boolean num_actuals_unknown, int num_actuals, int min, int max) Checks the number of parameters for a call to a native function.
void	visitNewFlow(BasicBlock b, ICallContext<?> c, IBlockState<?,?,?> s, String diff, String info) Registers new dataflow being propagated.
void	visitNodeTransfer(AbstractNode n) Registers a node transfer occurrence.
void	visitPropertyAccess(Node n, Value baseval) Checks whether the property access operation may dereference null or undefined.
void	visitPropertyRead(Node n, Set<ObjectLabel> objs, Str propertystr, BlockStateType state) Warns about writes to unknown properties; also registers a read operation on abstract objects.
void	visitPropertyWrite(Node n, Set<ObjectLabel> objs, Str propertystr) Warns about writes to unknown properties; also registers a write operation on abstract objects.
void	visitReachableNode(AbstractNode n) Registers a maybe reachable node.
void	visitRead(Node n, ICallContext<?> c, Value v) Record type information about a var/prop read.
void	visitReadNonThisVariable(ReadVariableNode n, Value v) Checks whether an absent variable is read.
void	visitReadProperty(ReadPropertyNode n, Set<ObjectLabel> objlabels, Str propertystr, boolean maybe, BlockStateType state) Checks whether the property read operation accesses an absent property and whether the operation returns null/undefined.
void	visitReadThis(ReadVariableNode n, Value v, BlockStateType state, ObjectLabel global_obj) Checks whether the read of 'this' yields the global object.
void	visitReadVariable(ReadVariableNode n, Value v, BlockStateType state) Checks whether the variable read yields null/undefined.
void	visitRecoveryGraph(int size) Registers a property recovery graph size.
void	visitUnknownValueResolve() Registers a recovery of an unknown value.
void	visitUserFunctionCall(Function f, AbstractNode call, boolean constructor) Checks whether the function is invoked both as a constructor (with 'new') and as a function/method (without 'new').
void	visitVariableAsRead(ReadVariableNode n, Value v) Registers that the given variable is read; also checks for suspicious type mixings.
void	visitVariableOrProperty(String var, SourceLocation loc, Value value) Registers the name, location, and value of a variable being read or written.
void	visitWriteVariable(WriteVariableNode n, Value v, BlockStateType state) Checks whether the assignment has no effect.

Methods inherited from class java.lang.Object

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

Constructor Detail

Monitoring

public Monitoring()

Constructs a new monitoring object.

Method Detail

addMessage

public void addMessage(AbstractNode n,
              Message.Severity severity,
              String msg)

Adds a message for the given node. If not in scan phase, nothing is done. Uses Status.MAYBE. Uses the message as key (must be a fixed string).

addMessage

public void addMessage(AbstractNode n,
              Message.Severity severity,
              String key,
              String msg)

Adds a message for the given node. If not in scan phase, nothing is done. Uses Status.MAYBE. The key must be a fixed string.

addMessageInfo

public void addMessageInfo(AbstractNode n,
                  Message.Severity severity,
                  String msg)

Adds a message for the given node. If not in scan phase, nothing is done. Uses Status.INFO. Uses the message as key (must be a fixed string).

beginScanPhase

public void beginScanPhase(FlowGraph fg)

Description copied from interface: IMonitoring

Initializes messages. Messages are not generated until this method is called.

Specified by:

beginScanPhase in interface IMonitoring<BlockStateType extends BlockState<BlockStateType,CallContextType,CallEdgeType>,CallContextType extends ICallContext<CallContextType>>

endScanPhase

public List<Message> endScanPhase(FlowGraph fg)

Finalizes messages by adding messages about unreachable code/functions, unused variables and parameters, dead assignments, and shadowing declarations.

Specified by:

endScanPhase in interface IMonitoring<BlockStateType extends BlockState<BlockStateType,CallContextType,CallEdgeType>,CallContextType extends ICallContext<CallContextType>>

Returns:

The sorted list of messages produced during scanning.

generateUnreachableMap

public void generateUnreachableMap()

Produces output showing the parts of the code that is determined unreachable by the analysis.

getMessages

public Set<Message> getMessages()

Returns the collected messages.

getReachableNodes

public Set<AbstractNode> getReachableNodes()

Returns the set of maybe reachable nodes.

getTotalNumberOfNodeTransfers

public int getTotalNumberOfNodeTransfers()

Description copied from interface: IMonitoring

Returns the total number of node transfers.

Specified by:

getTotalNumberOfNodeTransfers in interface IMonitoring<BlockStateType extends BlockState<BlockStateType,CallContextType,CallEdgeType>,CallContextType extends ICallContext<CallContextType>>

getTypeInformation

public Map<TypeCollector.VariableSummary,Value> getTypeInformation()

Returns the collected type information.

presentTypeInformation

public void presentTypeInformation()

Presents the collected type information.

reportShadowing

public void reportShadowing(FlowGraph fg)

Add messages about shadowing. Shadowing occurs when a declared variable clashes either local functions or parameters. This is a purely syntactic property, no analysis results are used.

toString

public String toString()

Returns a string description of the results.

Overrides:

toString in class Object

visitBlockTransfer

public void visitBlockTransfer()

Registers a block transfer occurrence. Also measures memory usage if enabled.

Specified by:

visitBlockTransfer in interface IMonitoring<BlockStateType extends BlockState<BlockStateType,CallContextType,CallEdgeType>,CallContextType extends ICallContext<CallContextType>>

visitCall

public void visitCall(AbstractNode n,
             boolean maybe_non_function,
             boolean maybe_function)

Registers a potential call/construct to a non-function value.

Parameters:

n - node responsible for the call

maybe_non_function - if set, this call may involve a non-function value

maybe_function - if set, this call may involve a function value

visitEvalCall

public void visitEvalCall(AbstractNode n,
                 Value v)

Registers a call to eval.

Parameters:

n - node that may call eval

v - value being eval'ed

visitFunction

public void visitFunction(Function f,
                 Collection<BlockStateType> entry_states)

Registers the function and checks whether it is unreachable.

Specified by:

visitFunction in interface IMonitoring<BlockStateType extends BlockState<BlockStateType,CallContextType,CallEdgeType>,CallContextType extends ICallContext<CallContextType>>

visitIf

public void visitIf(IfNode n,
           Value v)

Checks whether the branch condition is always true or always false.

Parameters:

n - if node

v - the boolean value

visitIn

public void visitIn(AbstractNode n,
           boolean maybe_v2_object,
           boolean maybe_v2_nonobject)

Checks whether the 'in' operation may fail.

Parameters:

n - node performing the operation

maybe_v2_object - if the second parameter may be an object value

maybe_v2_nonobject - if the second parameter may be a non-object value

visitInnerHTMLWrite

public void visitInnerHTMLWrite(Node n,
                       Value v)

Registers a write to innerHTML.

Parameters:

n - node where the write occurs

v - value being written

visitInstanceof

public void visitInstanceof(AbstractNode n,
                   boolean maybe_v2_non_function,
                   boolean maybe_v2_function,
                   boolean maybe_v2_prototype_primitive,
                   boolean maybe_v2_prototype_nonprimitive)

Checks whether the 'instanceof' operation may fail.

Parameters:

n - node performing the operation

maybe_v2_non_function - set if the second parameter may be a non-function value

maybe_v2_function - set if the second parameter may be a function value

maybe_v2_prototype_primitive - set if the prototype property of the second parameter may be a primitive value

maybe_v2_prototype_nonprimitive - set if the prototype property of the second parameter may be an object value

visitJoin

public void visitJoin()

Description copied from interface: IMonitoring

Registers a state join operation.

Specified by:

visitJoin in interface IMonitoring<BlockStateType extends BlockState<BlockStateType,CallContextType,CallEdgeType>,CallContextType extends ICallContext<CallContextType>>

visitNativeFunctionCall

public void visitNativeFunctionCall(AbstractNode n,
                           HostObject hostobject,
                           boolean num_actuals_unknown,
                           int num_actuals,
                           int min,
                           int max)

Checks the number of parameters for a call to a native function.

Parameters:

n - node responsible for the call

hostobject - the native function being called

num_actuals_unknown - if set, the number of actuals is unknown

num_actuals - number of actuals (if num_actuals_unknown is not set)

min - minimum number of parameters expected

max - maximum number of paramaters expected (-1 for any number)

visitNewFlow

public void visitNewFlow(BasicBlock b,
                ICallContext<?> c,
                IBlockState<?,?,?> s,
                String diff,
                String info)

Description copied from interface: IMonitoring

Registers new dataflow being propagated.

Specified by:

visitNewFlow in interface IMonitoring<BlockStateType extends BlockState<BlockStateType,CallContextType,CallEdgeType>,CallContextType extends ICallContext<CallContextType>>

visitNodeTransfer

public void visitNodeTransfer(AbstractNode n)

Description copied from interface: IMonitoring

Registers a node transfer occurrence.

Specified by:

visitNodeTransfer in interface IMonitoring<BlockStateType extends BlockState<BlockStateType,CallContextType,CallEdgeType>,CallContextType extends ICallContext<CallContextType>>

visitPropertyAccess

public void visitPropertyAccess(Node n,
                       Value baseval)

Checks whether the property access operation may dereference null or undefined.

Parameters:

n - operation that accesses a property

baseval - base value for the access

visitPropertyRead

public void visitPropertyRead(Node n,
                     Set<ObjectLabel> objs,
                     Str propertystr,
                     BlockStateType state)

Warns about writes to unknown properties; also registers a read operation on abstract objects. Properties named 'length' on array objects are ignored.

Parameters:

n - the node responsible for the read

objs - the objects being read from

propertystr - description of the property name

visitPropertyWrite

public void visitPropertyWrite(Node n,
                      Set<ObjectLabel> objs,
                      Str propertystr)

Warns about writes to unknown properties; also registers a write operation on abstract objects. Properties named 'length' on array objects are ignored. Writes to the arguments object are also ignored.

Parameters:

n - the node responsible for the write

objs - the objects being written to

propertystr - description of the property name

visitReachableNode

public void visitReachableNode(AbstractNode n)

Description copied from interface: IMonitoring

Registers a maybe reachable node.

Specified by:

visitReachableNode in interface IMonitoring<BlockStateType extends BlockState<BlockStateType,CallContextType,CallEdgeType>,CallContextType extends ICallContext<CallContextType>>

visitRead

public void visitRead(Node n,
             ICallContext<?> c,
             Value v)

Record type information about a var/prop read.

visitReadNonThisVariable

public void visitReadNonThisVariable(ReadVariableNode n,
                            Value v)

Checks whether an absent variable is read.

Parameters:

n - (non-this) read variable operation

v - the value being read

visitReadProperty

public void visitReadProperty(ReadPropertyNode n,
                     Set<ObjectLabel> objlabels,
                     Str propertystr,
                     boolean maybe,
                     BlockStateType state)

Checks whether the property read operation accesses an absent property and whether the operation returns null/undefined.

Parameters:

n - read property operation

objlabels - objects being read from

propertystr - description of the property name

maybe - if there may be more than one value

state - current abstract state

visitReadThis

public void visitReadThis(ReadVariableNode n,
                 Value v,
                 BlockStateType state,
                 ObjectLabel global_obj)

Checks whether the read of 'this' yields the global object.

Parameters:

n - (this) read variable operation

v - the value being read

state -

visitReadVariable

public void visitReadVariable(ReadVariableNode n,
                     Value v,
                     BlockStateType state)

Checks whether the variable read yields null/undefined. Variables named 'undefined' are ignored.

Parameters:

n - read variable operation

v - the value being read

visitRecoveryGraph

public void visitRecoveryGraph(int size)

Description copied from interface: IMonitoring

Registers a property recovery graph size.

Specified by:

visitRecoveryGraph in interface IMonitoring<BlockStateType extends BlockState<BlockStateType,CallContextType,CallEdgeType>,CallContextType extends ICallContext<CallContextType>>

visitUnknownValueResolve

public void visitUnknownValueResolve()

Description copied from interface: IMonitoring

Registers a recovery of an unknown value.

Specified by:

visitUnknownValueResolve in interface IMonitoring<BlockStateType extends BlockState<BlockStateType,CallContextType,CallEdgeType>,CallContextType extends ICallContext<CallContextType>>

visitUserFunctionCall

public void visitUserFunctionCall(Function f,
                         AbstractNode call,
                         boolean constructor)

Checks whether the function is invoked both as a constructor (with 'new') and as a function/method (without 'new').

Parameters:

f - function being called

call - node responsible for the call

constructor - if set, the call uses 'new'

visitVariableAsRead

public void visitVariableAsRead(ReadVariableNode n,
                       Value v)

Registers that the given variable is read; also checks for suspicious type mixings.

Parameters:

n - (non-this) read variable operation

v - value being read

visitVariableOrProperty

public void visitVariableOrProperty(String var,
                           SourceLocation loc,
                           Value value)

Registers the name, location, and value of a variable being read or written.

visitWriteVariable

public void visitWriteVariable(WriteVariableNode n,
                      Value v,
                      BlockStateType state)

Checks whether the assignment has no effect.

Parameters:

n - write variable operation

v - value being written

state - current abstract state