ObjCContainersASTChecker.cpp [plain text]
#include "ClangSACheckers.h"
#include "clang/Analysis/AnalysisContext.h"
#include "clang/AST/StmtVisitor.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/StaticAnalyzer/Core/Checker.h"
#include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/Support/raw_ostream.h"
using namespace clang;
using namespace ento;
namespace {
class WalkAST : public StmtVisitor<WalkAST> {
BugReporter &BR;
AnalysisDeclContext* AC;
ASTContext &ASTC;
uint64_t PtrWidth;
static const unsigned InvalidArgIndex = UINT_MAX;
inline bool isPointerSize(const Type *T) {
if (!T)
return true;
if (T->isIncompleteType())
return true;
return (ASTC.getTypeSize(T) == PtrWidth);
}
inline bool hasPointerToPointerSizedType(const Expr *E) {
QualType T = E->getType();
const Type *TP = T.getTypePtr();
QualType PointeeT = TP->getPointeeType();
if (!PointeeT.isNull()) {
if (const Type *TElem = PointeeT->getArrayElementTypeNoTypeQual())
if (isPointerSize(TElem))
return true;
return isPointerSize(PointeeT.getTypePtr());
}
if (const Type *TElem = TP->getArrayElementTypeNoTypeQual())
return isPointerSize(TElem);
if (E->isNullPointerConstant(ASTC, Expr::NPC_ValueDependentIsNull))
return true;
return false;
}
public:
WalkAST(BugReporter &br, AnalysisDeclContext* ac)
: BR(br), AC(ac), ASTC(AC->getASTContext()),
PtrWidth(ASTC.getTargetInfo().getPointerWidth(0)) {}
void VisitChildren(Stmt *S);
void VisitStmt(Stmt *S) { VisitChildren(S); }
void VisitCallExpr(CallExpr *CE);
};
}
static StringRef getCalleeName(CallExpr *CE) {
const FunctionDecl *FD = CE->getDirectCallee();
if (!FD)
return StringRef();
IdentifierInfo *II = FD->getIdentifier();
if (!II) return StringRef();
return II->getName();
}
void WalkAST::VisitCallExpr(CallExpr *CE) {
StringRef Name = getCalleeName(CE);
if (Name.empty())
return;
const Expr *Arg = 0;
unsigned ArgNum = InvalidArgIndex;
if (Name.equals("CFArrayCreate") || Name.equals("CFSetCreate")) {
ArgNum = 1;
Arg = CE->getArg(ArgNum)->IgnoreParenCasts();
if (hasPointerToPointerSizedType(Arg))
return;
}
if (Arg == 0 && Name.equals("CFDictionaryCreate")) {
ArgNum = 1;
Arg = CE->getArg(ArgNum)->IgnoreParenCasts();
if (hasPointerToPointerSizedType(Arg)) {
ArgNum = 2;
Arg = CE->getArg(ArgNum)->IgnoreParenCasts();
if (hasPointerToPointerSizedType(Arg))
return;
}
}
if (ArgNum != InvalidArgIndex) {
assert(ArgNum == 1 || ArgNum == 2);
SmallString<256> BufName;
llvm::raw_svector_ostream OsName(BufName);
assert(ArgNum == 1 || ArgNum == 2);
OsName << " Invalid use of '" << Name << "'" ;
SmallString<256> Buf;
llvm::raw_svector_ostream Os(Buf);
Os << " The "<< ((ArgNum == 1) ? "second" : "third") << " argument to '"
<< Name << "' must be a C array of pointer-sized values, not '"
<< Arg->getType().getAsString() << "'";
SourceRange R = Arg->getSourceRange();
PathDiagnosticLocation CELoc =
PathDiagnosticLocation::createBegin(CE, BR.getSourceManager(), AC);
BR.EmitBasicReport(AC->getDecl(),
OsName.str(), categories::CoreFoundationObjectiveC,
Os.str(), CELoc, &R, 1);
}
VisitChildren(CE);
}
void WalkAST::VisitChildren(Stmt *S) {
for (Stmt::child_iterator I = S->child_begin(), E = S->child_end(); I!=E; ++I)
if (Stmt *child = *I)
Visit(child);
}
namespace {
class ObjCContainersASTChecker : public Checker<check::ASTCodeBody> {
public:
void checkASTCodeBody(const Decl *D, AnalysisManager& Mgr,
BugReporter &BR) const {
WalkAST walker(BR, Mgr.getAnalysisDeclContext(D));
walker.Visit(D->getBody());
}
};
}
void ento::registerObjCContainersASTChecker(CheckerManager &mgr) {
mgr.registerChecker<ObjCContainersASTChecker>();
}