Add the clang library to the repo (with some of my changes, too).

1 files changed, 116 insertions, 0 deletions

diff --git a/clang/lib/StaticAnalyzer/Checkers/MacOSXAPIChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/MacOSXAPIChecker.cpp
new file mode 100644
index 0000000..cfdb55d
--- /dev/null
+++ b/clang/lib/StaticAnalyzer/Checkers/MacOSXAPIChecker.cpp
@@ -0,0 +1,116 @@
+// MacOSXAPIChecker.h - Checks proper use of various MacOS X APIs --*- C++ -*-//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This defines MacOSXAPIChecker, which is an assortment of checks on calls
+// to various, widely used Mac OS X functions.
+//
+// FIXME: What's currently in BasicObjCFoundationChecks.cpp should be migrated
+// to here, using the new Checker interface.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ClangSACheckers.h"
+#include "clang/StaticAnalyzer/Core/Checker.h"
+#include "clang/StaticAnalyzer/Core/CheckerManager.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
+#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h"
+#include "clang/Basic/TargetInfo.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringSwitch.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace clang;
+using namespace ento;
+
+namespace {
+class MacOSXAPIChecker : public Checker< check::PreStmt<CallExpr> > {
+  mutable OwningPtr<BugType> BT_dispatchOnce;
+
+public:
+  void checkPreStmt(const CallExpr *CE, CheckerContext &C) const;
+
+  void CheckDispatchOnce(CheckerContext &C, const CallExpr *CE,
+                         StringRef FName) const;
+
+  typedef void (MacOSXAPIChecker::*SubChecker)(CheckerContext &,
+                                               const CallExpr *,
+                                               StringRef FName) const;
+};
+} //end anonymous namespace
+
+//===----------------------------------------------------------------------===//
+// dispatch_once and dispatch_once_f
+//===----------------------------------------------------------------------===//
+
+void MacOSXAPIChecker::CheckDispatchOnce(CheckerContext &C, const CallExpr *CE,
+                                         StringRef FName) const {
+  if (CE->getNumArgs() < 1)
+    return;
+
+  // Check if the first argument is stack allocated.  If so, issue a warning
+  // because that's likely to be bad news.
+  ProgramStateRef state = C.getState();
+  const MemRegion *R =
+    state->getSVal(CE->getArg(0), C.getLocationContext()).getAsRegion();
+  if (!R || !isa<StackSpaceRegion>(R->getMemorySpace()))
+    return;
+
+  ExplodedNode *N = C.generateSink(state);
+  if (!N)
+    return;
+
+  if (!BT_dispatchOnce)
+    BT_dispatchOnce.reset(new BugType("Improper use of 'dispatch_once'",
+                                      "Mac OS X API"));
+
+  SmallString<256> S;
+  llvm::raw_svector_ostream os(S);
+  os << "Call to '" << FName << "' uses";
+  if (const VarRegion *VR = dyn_cast<VarRegion>(R))
+    os << " the local variable '" << VR->getDecl()->getName() << '\'';
+  else
+    os << " stack allocated memory";
+  os << " for the predicate value.  Using such transient memory for "
+        "the predicate is potentially dangerous.";
+  if (isa<VarRegion>(R) && isa<StackLocalsSpaceRegion>(R->getMemorySpace()))
+    os << "  Perhaps you intended to declare the variable as 'static'?";
+
+  BugReport *report = new BugReport(*BT_dispatchOnce, os.str(), N);
+  report->addRange(CE->getArg(0)->getSourceRange());
+  C.EmitReport(report);
+}
+
+//===----------------------------------------------------------------------===//
+// Central dispatch function.
+//===----------------------------------------------------------------------===//
+
+void MacOSXAPIChecker::checkPreStmt(const CallExpr *CE,
+                                    CheckerContext &C) const {
+  StringRef Name = C.getCalleeName(CE);
+  if (Name.empty())
+    return;
+
+  SubChecker SC =
+    llvm::StringSwitch<SubChecker>(Name)
+      .Cases("dispatch_once", "dispatch_once_f",
+             &MacOSXAPIChecker::CheckDispatchOnce)
+      .Default(NULL);
+
+  if (SC)
+    (this->*SC)(C, CE, Name);
+}
+
+//===----------------------------------------------------------------------===//
+// Registration.
+//===----------------------------------------------------------------------===//
+
+void ento::registerMacOSXAPIChecker(CheckerManager &mgr) {
+  mgr.registerChecker<MacOSXAPIChecker>();
+}