#include "clang/Analysis/LocalCheckers.h"
#include "clang/Analysis/PathSensitive/BugReporter.h"
+#include "clang/Analysis/PathSensitive/GRExprEngine.h"
+#include "BasicObjCFoundationChecks.h"
+#include "llvm/Support/Compiler.h"
#include "clang/AST/DeclObjC.h"
-#include "clang/AST/Type.h"
-#include "clang/AST/ASTContext.h"
+#include "clang/AST/Decl.h"
+#include "llvm/ADT/SmallVector.h"
using namespace clang;
-void clang::CheckNSError(ObjCImplementationDecl* ID, BugReporter& BR) {
- // Look at the @interface for this class.
- ObjCInterfaceDecl* D = ID->getClassInterface();
+namespace {
+class VISIBILITY_HIDDEN NSErrorCheck : public BugTypeCacheLocation {
+
+ void EmitGRWarnings(GRBugReporter& BR);
- // Get the ASTContext. Useful for querying type information.
- ASTContext &Ctx = BR.getContext();
+ void CheckSignature(ObjCMethodDecl& MD, QualType& ResultTy,
+ llvm::SmallVectorImpl<VarDecl*>& Params,
+ IdentifierInfo* NSErrorII);
+
+ bool CheckArgument(QualType ArgTy, IdentifierInfo* NSErrorII);
- // Get the IdentifierInfo* for "NSError".
- IdentifierInfo* NSErrorII = &Ctx.Idents.get("NSError");
+public:
+ void EmitWarnings(BugReporter& BR) { EmitGRWarnings(cast<GRBugReporter>(BR));}
+ const char* getName() const { return "NSError** null dereference"; }
+};
+
+} // end anonymous namespace
- // Scan the methods. See if any of them have an argument of type NSError**.
- for (ObjCInterfaceDecl::instmeth_iterator I=D->instmeth_begin(),
- E=D->instmeth_end(); I!=E; ++I) {
+BugType* clang::CreateNSErrorCheck() {
+ return new NSErrorCheck();
+}
- // Get the method declaration.
- ObjCMethodDecl* M = *I;
-
- // Check for a non-void return type.
- if (M->getResultType() != Ctx.VoidTy)
- continue;
+void NSErrorCheck::EmitGRWarnings(GRBugReporter& BR) {
+ // Get the analysis engine and the exploded analysis graph.
+ GRExprEngine& Eng = BR.getEngine();
+ GRExprEngine::GraphTy& G = Eng.getGraph();
+
+ // Get the declaration of the method/function that was analyzed.
+ Decl& CodeDecl = G.getCodeDecl();
+
+ ObjCMethodDecl* MD = dyn_cast<ObjCMethodDecl>(&CodeDecl);
+ if (!MD)
+ return;
+
+ // Get the ASTContext, which is useful for querying type information.
+ ASTContext &Ctx = BR.getContext();
- for (ObjCMethodDecl::param_iterator PI=M->param_begin(),
- PE=M->param_end(); PI!=PE; ++PI) {
-
- const PointerType* PPT = (*PI)->getType()->getAsPointerType();
- if (!PPT) continue;
-
- const PointerType* PT = PPT->getPointeeType()->getAsPointerType();
- if (!PT) continue;
-
- const ObjCInterfaceType *IT =
- PT->getPointeeType()->getAsObjCInterfaceType();
-
- if (!IT) continue;
-
- // Check if IT is "NSError".
- if (IT->getDecl()->getIdentifier() == NSErrorII) {
- // Documentation: "Creating and Returning NSError Objects"
- BR.EmitBasicReport("Bad return type when passing NSError**",
- "Method accepting NSError** argument should have "
- "non-void return value to indicate that an error occurred.",
- M->getLocStart());
- break;
- }
- }
+ QualType ResultTy;
+ llvm::SmallVector<VarDecl*, 5> Params;
+ CheckSignature(*MD, ResultTy, Params, &Ctx.Idents.get("NSError"));
+
+ if (Params.empty())
+ return;
+
+ if (ResultTy == Ctx.VoidTy) {
+ BR.EmitBasicReport("Bad return type when passing NSError**",
+ "Method accepting NSError** argument should have "
+ "non-void return value to indicate that an error occurred.",
+ CodeDecl.getLocation());
+
}
}
+
+void NSErrorCheck::CheckSignature(ObjCMethodDecl& M, QualType& ResultTy,
+ llvm::SmallVectorImpl<VarDecl*>& Params,
+ IdentifierInfo* NSErrorII) {
+
+ ResultTy = M.getResultType();
+
+ for (ObjCMethodDecl::param_iterator I=M.param_begin(),
+ E=M.param_end(); I!=E; ++I)
+ if (CheckArgument((*I)->getType(), NSErrorII))
+ Params.push_back(*I);
+}
+
+bool NSErrorCheck::CheckArgument(QualType ArgTy, IdentifierInfo* NSErrorII) {
+ const PointerType* PPT = ArgTy->getAsPointerType();
+ if (!PPT) return false;
+
+ const PointerType* PT = PPT->getPointeeType()->getAsPointerType();
+ if (!PT) return false;
+
+ const ObjCInterfaceType *IT =
+ PT->getPointeeType()->getAsObjCInterfaceType();
+
+ if (!IT) return false;
+ return IT->getDecl()->getIdentifier() == NSErrorII;
+}