Commit 5b3983ba authored by Balázs Kéri's avatar Balázs Kéri
Browse files

[analyzer]StreamChecker refactoring (NFC). 

Reviewers: Szelethus

Reviewed By: Szelethus

Subscribers: xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, donat.nagy, Charusso, dkrupp, Szelethus, gamesh411, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D73359
parent 034c2c67

clang/lib/StaticAnalyzer/Checkers/StreamChecker.cpp

+42 −39
Original line number Diff line number Diff line
@@ -94,15 +94,15 @@ private: 
  void evalFreopen(const CallEvent &Call, CheckerContext &C) const;

  void evalFclose(const CallEvent &Call, CheckerContext &C) const;

  void evalFseek(const CallEvent &Call, CheckerContext &C) const;



  void checkArgNullStream(const CallEvent &Call, CheckerContext &C,

                          unsigned ArgI) const;

  bool checkNullStream(SVal SV, CheckerContext &C,

                       ProgramStateRef &State) const;

  void checkFseekWhence(SVal SV, CheckerContext &C,

                        ProgramStateRef &State) const;

  bool checkDoubleClose(const CallEvent &Call, CheckerContext &C,

                        ProgramStateRef &State) const;



  ProgramStateRef checkNullStream(SVal SV, CheckerContext &C,

                                  ProgramStateRef State) const;

  ProgramStateRef checkFseekWhence(SVal SV, CheckerContext &C,

                                   ProgramStateRef State) const;

  ProgramStateRef checkDoubleClose(const CallEvent &Call, CheckerContext &C,

                                   ProgramStateRef State) const;

};



} // end anonymous namespace
@@ -176,9 +176,8 @@ void StreamChecker::evalFreopen(const CallEvent &Call, 
    return;

  // Do not allow NULL as passed stream pointer.

  // This is not specified in the man page but may crash on some system.

  checkNullStream(*StreamVal, C, State);

  // Check if error was generated.

  if (C.isDifferent())

  State = checkNullStream(*StreamVal, C, State);

  if (!State)

    return;



  SymbolRef StreamSym = StreamVal->getAsSymbol();
@@ -208,7 +207,8 @@ void StreamChecker::evalFreopen(const CallEvent &Call, 


void StreamChecker::evalFclose(const CallEvent &Call, CheckerContext &C) const {

  ProgramStateRef State = C.getState();

  if (checkDoubleClose(Call, C, State))

  State = checkDoubleClose(Call, C, State);

  if (State)

    C.addTransition(State);

}
@@ -219,30 +219,31 @@ void StreamChecker::evalFseek(const CallEvent &Call, CheckerContext &C) const { 


  ProgramStateRef State = C.getState();



  bool StateChanged = checkNullStream(Call.getArgSVal(0), C, State);

  // Check if error was generated.

  if (C.isDifferent())

  State = checkNullStream(Call.getArgSVal(0), C, State);

  if (!State)

    return;



  // Check the legality of the 'whence' argument of 'fseek'.

  State =

      checkFseekWhence(State->getSVal(AE2, C.getLocationContext()), C, State);

  if (!State)

    return;



  if (!C.isDifferent() && StateChanged)

  C.addTransition(State);

}



void StreamChecker::checkArgNullStream(const CallEvent &Call, CheckerContext &C,

                                       unsigned ArgI) const {

  ProgramStateRef State = C.getState();

  if (checkNullStream(Call.getArgSVal(ArgI), C, State))

  State = checkNullStream(Call.getArgSVal(ArgI), C, State);

  if (State)

    C.addTransition(State);

}



bool StreamChecker::checkNullStream(SVal SV, CheckerContext &C,

                                    ProgramStateRef &State) const {

ProgramStateRef StreamChecker::checkNullStream(SVal SV, CheckerContext &C,

                                               ProgramStateRef State) const {

  Optional<DefinedSVal> DV = SV.getAs<DefinedSVal>();

  if (!DV)

    return false;

    return State;



  ConstraintManager &CM = C.getConstraintManager();

  ProgramStateRef StateNotNull, StateNull;
@@ -256,26 +257,22 @@ bool StreamChecker::checkNullStream(SVal SV, CheckerContext &C, 
      C.emitReport(std::make_unique<PathSensitiveBugReport>(

          *BT_nullfp, BT_nullfp->getDescription(), N));

    }

    return false;

    return nullptr;

  }



  if (StateNotNull) {

    State = StateNotNull;

    return true;

  }



  return false;

  return StateNotNull;

}



void StreamChecker::checkFseekWhence(SVal SV, CheckerContext &C,

                                     ProgramStateRef &State) const {

// Check the legality of the 'whence' argument of 'fseek'.

ProgramStateRef StreamChecker::checkFseekWhence(SVal SV, CheckerContext &C,

                                                ProgramStateRef State) const {

  Optional<nonloc::ConcreteInt> CI = SV.getAs<nonloc::ConcreteInt>();

  if (!CI)

    return;

    return State;



  int64_t X = CI->getValue().getSExtValue();

  if (X >= 0 && X <= 2)

    return;

    return State;



  if (ExplodedNode *N = C.generateNonFatalErrorNode(State)) {

    if (!BT_illegalwhence)
@@ -285,20 +282,24 @@ void StreamChecker::checkFseekWhence(SVal SV, CheckerContext &C, 
                         "SEEK_SET, SEEK_END, or SEEK_CUR."));

    C.emitReport(std::make_unique<PathSensitiveBugReport>(

        *BT_illegalwhence, BT_illegalwhence->getDescription(), N));

    return nullptr;

  }



  return State;

}



bool StreamChecker::checkDoubleClose(const CallEvent &Call, CheckerContext &C,

                                     ProgramStateRef &State) const {

ProgramStateRef StreamChecker::checkDoubleClose(const CallEvent &Call,

                                                CheckerContext &C,

                                                ProgramStateRef State) const {

  SymbolRef Sym = Call.getArgSVal(0).getAsSymbol();

  if (!Sym)

    return false;

    return State;



  const StreamState *SS = State->get<StreamMap>(Sym);



  // If the file stream is not tracked, return.

  if (!SS)

    return false;

    return State;



  // Check: Double close a File Descriptor could cause undefined behaviour.

  // Conforming to man-pages
@@ -311,14 +312,16 @@ bool StreamChecker::checkDoubleClose(const CallEvent &Call, CheckerContext &C, 
                                   " closed. Cause undefined behaviour."));

      C.emitReport(std::make_unique<PathSensitiveBugReport>(

          *BT_doubleclose, BT_doubleclose->getDescription(), N));

      return nullptr;

    }

    return false;



    return State;

  }



  // Close the File Descriptor.

  State = State->set<StreamMap>(Sym, StreamState::getClosed());



  return true;

  return State;

}



void StreamChecker::checkDeadSymbols(SymbolReaper &SymReaper,