2 files changed, 152 insertions, 0 deletions
diff --git a/lib/Analysis/BasicObjCFoundationChecks.cpp b/lib/Analysis/BasicObjCFoundationChecks.cpp
new file mode 100644
index 0000000000..0fae7ddcd3
--- /dev/null
+++ b/lib/Analysis/BasicObjCFoundationChecks.cpp
@@ -0,0 +1,139 @@
+//== BasicObjCFoundationChecks.cpp - Simple Apple-Foundation checks -*- C++ -*--
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines BasicObjCFoundationChecks, a class that encapsulates
+//  a set of simple checks to run on Objective-C code using Apple's Foundation
+//  classes.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Analysis/PathSensitive/ExplodedGraph.h"
+#include "clang/Analysis/PathSensitive/GRSimpleAPICheck.h"
+#include "clang/Analysis/PathSensitive/ValueState.h"
+#include "clang/Analysis/PathSensitive/AnnotatedPath.h"
+#include "clang/Analysis/PathDiagnostic.h"
+#include "clang/AST/Expr.h"
+#include "clang/AST/ASTContext.h"
+#include "llvm/Support/Compiler.h"
+
+#include <vector>
+
+using namespace clang;
+  
+namespace {
+  
+class VISIBILITY_HIDDEN BasicObjCFoundationChecks : public GRSimpleAPICheck {
+
+ ASTContext &Ctx;
+ ValueStateManager* VMgr;
+ std::list<AnnotatedPath<ValueState> > Errors;
+      
+ RVal GetRVal(ValueState* St, Expr* E) { return VMgr->GetRVal(St, E); }
+      
+ bool isNSString(ObjCInterfaceType* T, const char* suffix);
+ bool AuditNSString(NodeTy* N, ObjCMessageExpr* ME);
+      
+ void RegisterError(NodeTy* N, Expr* E, const char *msg);
+
+public:
+  BasicObjCFoundationChecks(ASTContext& ctx, ValueStateManager* vmgr) 
+    : Ctx(ctx), VMgr(vmgr) {}
+      
+  virtual ~BasicObjCFoundationChecks() {}
+  
+  virtual bool Audit(ExplodedNode<ValueState>* N);
+};
+  
+} // end anonymous namespace
+
+
+bool BasicObjCFoundationChecks::Audit(ExplodedNode<ValueState>* N) {
+  
+  ObjCMessageExpr* ME =
+    cast<ObjCMessageExpr>(cast<PostStmt>(N->getLocation()).getStmt());
+  
+  Expr* Receiver = ME->getReceiver();
+  
+  if (!Receiver)
+    return false;
+  
+  assert (Receiver->getType()->isPointerType());
+
+  const PointerType* T = Receiver->getType()->getAsPointerType();
+
+  ObjCInterfaceType* ReceiverType =
+    dyn_cast<ObjCInterfaceType>(T->getPointeeType().getTypePtr());
+  
+  if (!ReceiverType)
+    return false;
+  
+  const char* name = ReceiverType->getDecl()->getIdentifier()->getName();  
+
+  if (name[0] != 'N' || name[1] != 'S')
+    return false;
+      
+  name += 2;
+  
+  // FIXME: Make all of this faster.
+  
+  if (isNSString(ReceiverType, name))
+    return AuditNSString(N, ME);
+
+  return false;  
+}
+
+//===----------------------------------------------------------------------===//
+// Error reporting.
+//===----------------------------------------------------------------------===//
+
+
+void BasicObjCFoundationChecks::RegisterError(NodeTy* N,
+                                              Expr* E, const char *msg) {
+  
+  Errors.push_back(AnnotatedPath<ValueState>());
+  Errors.back().push_back(N, msg, E);
+}
+
+//===----------------------------------------------------------------------===//
+// NSString checking.
+//===----------------------------------------------------------------------===//
+
+bool BasicObjCFoundationChecks::isNSString(ObjCInterfaceType* T,
+                                           const char* suffix) {
+  
+  return !strcmp("String", suffix) || !strcmp("MutableString", suffix);
+}
+
+bool BasicObjCFoundationChecks::AuditNSString(NodeTy* N, 
+                                              ObjCMessageExpr* ME) {
+  
+  Selector S = ME->getSelector();
+  
+  if (S.isUnarySelector())
+    return false;
+
+  // FIXME: This is going to be really slow doing these checks with
+  //  lexical comparisons.
+  
+  std::string name = S.getName();
+  ValueState* St = N->getState();
+  
+  if (name == "compare:") {
+    // Check if the compared NSString is nil.
+    Expr * E = ME->getArg(0);
+    RVal X = GetRVal(St, E);
+    
+    if (isa<lval::ConcreteInt>(X)) {
+      RegisterError(N, E,
+                    "Argument to NSString method 'compare:' cannot be nil.");
+    }
+  }
+  
+  return false;
+}
diff --git a/lib/Analysis/GRExprEngine.cpp b/lib/Analysis/GRExprEngine.cpp
index bce1cbd90c..b6f164a57f 100644
--- a/lib/Analysis/GRExprEngine.cpp
+++ b/lib/Analysis/GRExprEngine.cpp
@@ -407,6 +407,19 @@ void GRExprEngine::ProcessStmt(Stmt* S, StmtNodeBuilder& builder) {
   CurrentStmt = S;
   NodeSet Dst;
   
+  // Set up our simple checks.
+  
+  if (!MsgExprChecks.empty())
+    Builder->setObjCMsgExprAuditors(
+      (GRNodeAuditor<ValueState>**) &MsgExprChecks[0],
+      (GRNodeAuditor<ValueState>**) (&MsgExprChecks[0] + MsgExprChecks.size()));
+
+  
+  if (!CallChecks.empty())
+    Builder->setCallExprAuditors(
+      (GRNodeAuditor<ValueState>**) &CallChecks[0],
+      (GRNodeAuditor<ValueState>**) (&CallChecks[0] + CallChecks.size()));
+  
   // Create the cleaned state.
 
   CleanedState = StateMgr.RemoveDeadBindings(StmtEntryNode->getState(),