[analyzer] StdLibraryFunctionsChecker: Add support for new functions

`toupper`, `tolower`, `toascii` functions were added to
StdLibraryFunctionsChecker to fully cover CERT STR37-C rule:
https://wiki.sei.cmu.edu/confluence/x/BNcxBQ

Differential Revision: https://reviews.llvm.org/D85093

1 files changed, 22 insertions, 10 deletions

diff --git a/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp
index e437c33..030f995 100644
--- a/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp
@@ -40,12 +40,12 @@
 //
 // The following standard C functions are currently supported:
 //
-//   fgetc      getline   isdigit   isupper
+//   fgetc      getline   isdigit   isupper     toascii
 //   fread      isalnum   isgraph   isxdigit
 //   fwrite     isalpha   islower   read
 //   getc       isascii   isprint   write
-//   getchar    isblank   ispunct
-//   getdelim   iscntrl   isspace
+//   getchar    isblank   ispunct   toupper
+//   getdelim   iscntrl   isspace   tolower
 //
 //===----------------------------------------------------------------------===//
 
@@ -147,9 +147,7 @@ class StdLibraryFunctionsChecker
     RangeConstraint(ArgNo ArgN, RangeKind Kind, const IntRangeVector &Args)
         : ValueConstraint(ArgN), Kind(Kind), Args(Args) {}
 
-    const IntRangeVector &getRanges() const {
-      return Args;
-    }
+    const IntRangeVector &getRanges() const { return Args; }
 
   private:
     ProgramStateRef applyAsOutOfRange(ProgramStateRef State,
@@ -158,6 +156,7 @@ class StdLibraryFunctionsChecker
     ProgramStateRef applyAsWithinRange(ProgramStateRef State,
                                        const CallEvent &Call,
                                        const Summary &Summary) const;
+
   public:
     ProgramStateRef apply(ProgramStateRef State, const CallEvent &Call,
                           const Summary &Summary,
@@ -408,7 +407,7 @@ class StdLibraryFunctionsChecker
       return *this;
     }
 
-    Summary &Case(ConstraintSet&& CS) {
+    Summary &Case(ConstraintSet &&CS) {
       CaseConstraints.push_back(std::move(CS));
       return *this;
     }
@@ -796,13 +795,13 @@ void StdLibraryFunctionsChecker::initFunctionSummaries(
   const QualType LongLongTy = ACtx.LongLongTy;
   const QualType SizeTy = ACtx.getSizeType();
 
-  const QualType VoidPtrTy = ACtx.VoidPtrTy; // void *
+  const QualType VoidPtrTy = ACtx.VoidPtrTy;            // void *
   const QualType IntPtrTy = ACtx.getPointerType(IntTy); // int *
   const QualType UnsignedIntPtrTy =
       ACtx.getPointerType(UnsignedIntTy); // unsigned int *
   const QualType VoidPtrRestrictTy = getRestrictTy(VoidPtrTy);
   const QualType ConstVoidPtrTy =
-      ACtx.getPointerType(ACtx.VoidTy.withConst()); // const void *
+      ACtx.getPointerType(ACtx.VoidTy.withConst());            // const void *
   const QualType CharPtrTy = ACtx.getPointerType(ACtx.CharTy); // char *
   const QualType CharPtrRestrictTy = getRestrictTy(CharPtrTy);
   const QualType ConstCharPtrTy =
@@ -1117,6 +1116,18 @@ void StdLibraryFunctionsChecker::initFunctionSummaries(
           .Case({ArgumentCondition(0U, OutOfRange,
                                    {{'0', '9'}, {'A', 'F'}, {'a', 'f'}}),
                  ReturnValueCondition(WithinRange, SingleValue(0))}));
+  addToFunctionSummaryMap(
+      "toupper", Summary(ArgTypes{IntTy}, RetType{IntTy}, EvalCallAsPure)
+                     .ArgConstraint(ArgumentCondition(
+                         0U, WithinRange, {{EOFv, EOFv}, {0, UCharRangeMax}})));
+  addToFunctionSummaryMap(
+      "tolower", Summary(ArgTypes{IntTy}, RetType{IntTy}, EvalCallAsPure)
+                     .ArgConstraint(ArgumentCondition(
+                         0U, WithinRange, {{EOFv, EOFv}, {0, UCharRangeMax}})));
+  addToFunctionSummaryMap(
+      "toascii", Summary(ArgTypes{IntTy}, RetType{IntTy}, EvalCallAsPure)
+                     .ArgConstraint(ArgumentCondition(
+                         0U, WithinRange, {{EOFv, EOFv}, {0, UCharRangeMax}})));
 
   // The getc() family of functions that returns either a char or an EOF.
   if (FilePtrTy) {
@@ -2033,7 +2044,8 @@ void ento::registerStdCLibraryFunctionsChecker(CheckerManager &mgr) {
       mgr.getAnalyzerOptions().getCheckerBooleanOption(Checker, "ModelPOSIX");
 }
 
-bool ento::shouldRegisterStdCLibraryFunctionsChecker(const CheckerManager &mgr) {
+bool ento::shouldRegisterStdCLibraryFunctionsChecker(
+    const CheckerManager &mgr) {
   return true;
 }