Move CocoaConventions.[h,cpp] from libChecker

to libAnalysis.  Similar to Format (format string checking), 
CocoaConventions has the
potential to serve clients other than the
static analyzer.

llvm-svn: 122040

clang/lib/Analysis/CocoaConventions.cpp

@@ -0,0 +1,172 @@
+//===- CocoaConventions.h - Special handling of Cocoa conventions -*- 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 
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Analysis/DomainSpecific/CocoaConventions.h"
+#include "clang/AST/Type.h"
+#include "clang/AST/Decl.h"
+#include "clang/AST/DeclObjC.h"
+#include "llvm/ADT/StringExtras.h"
+
+using namespace clang;
+
+using llvm::StringRef;
+
+// The "fundamental rule" for naming conventions of methods:
+//  (url broken into two lines)
+//  http://developer.apple.com/documentation/Cocoa/Conceptual/
+//     MemoryMgmt/Tasks/MemoryManagementRules.html
+//
+// "You take ownership of an object if you create it using a method whose name
+//  begins with "alloc" or "new" or contains "copy" (for example, alloc,
+//  newObject, or mutableCopy), or if you send it a retain message. You are
+//  responsible for relinquishing ownership of objects you own using release
+//  or autorelease. Any other time you receive an object, you must
+//  not release it."
+//
+
+static bool isWordEnd(char ch, char prev, char next) {
+  return ch == '\0'
+      || (islower(prev) && isupper(ch)) // xxxC
+      || (isupper(prev) && isupper(ch) && islower(next)) // XXCreate
+      || !isalpha(ch);
+}
+
+static const char* parseWord(const char* s) {
+  char ch = *s, prev = '\0';
+  assert(ch != '\0');
+  char next = *(s+1);
+  while (!isWordEnd(ch, prev, next)) {
+    prev = ch;
+    ch = next;
+    next = *((++s)+1);
+  }
+  return s;
+}
+
+cocoa::NamingConvention cocoa::deriveNamingConvention(Selector S) {
+  IdentifierInfo *II = S.getIdentifierInfoForSlot(0);
+
+  if (!II)
+    return NoConvention;
+
+  const char *s = II->getNameStart();
+
+  // A method/function name may contain a prefix.  We don't know it is there,
+  // however, until we encounter the first '_'.
+  while (*s != '\0') {
+    // Skip '_', numbers, ':', etc.
+    if (*s == '_' || !isalpha(*s)) {      
+      ++s;
+      continue;
+    }
+    break;
+  }
+
+  // Parse the first word, and look for specific keywords.
+  const char *wordEnd = parseWord(s);
+  assert(wordEnd > s);
+  unsigned len = wordEnd - s;
+
+  switch (len) {
+    default:
+      return NoConvention;
+    case 3:
+      // Methods starting with 'new' follow the create rule.
+      return (memcmp(s, "new", 3) == 0) ? CreateRule : NoConvention;
+    case 4:
+      // Methods starting with 'copy' follow the create rule.
+      if (memcmp(s, "copy", 4) == 0)
+        return CreateRule;
+      // Methods starting with 'init' follow the init rule.
+      if (memcmp(s, "init", 4) == 0)
+        return InitRule;
+      return NoConvention;
+    case 5:
+      return (memcmp(s, "alloc", 5) == 0) ? CreateRule : NoConvention;
+    case 7:
+      // Methods starting with 'mutableCopy' follow the create rule.
+      if (memcmp(s, "mutable", 7) == 0) {
+        // Look at the next word to see if it is "Copy".
+        s = wordEnd;
+        wordEnd = parseWord(s);
+        len = wordEnd - s;
+        if (len == 4 && memcmp(s, "Copy", 4) == 0)
+          return CreateRule;
+      }
+      return NoConvention;
+  }
+}
+
+bool cocoa::isRefType(QualType RetTy, llvm::StringRef Prefix,
+                      llvm::StringRef Name) {
+  // Recursively walk the typedef stack, allowing typedefs of reference types.
+  while (TypedefType* TD = dyn_cast<TypedefType>(RetTy.getTypePtr())) {
+    llvm::StringRef TDName = TD->getDecl()->getIdentifier()->getName();
+    if (TDName.startswith(Prefix) && TDName.endswith("Ref"))
+      return true;
+    
+    RetTy = TD->getDecl()->getUnderlyingType();
+  }
+  
+  if (Name.empty())
+    return false;
+  
+  // Is the type void*?
+  const PointerType* PT = RetTy->getAs<PointerType>();
+  if (!(PT->getPointeeType().getUnqualifiedType()->isVoidType()))
+    return false;
+  
+  // Does the name start with the prefix?
+  return Name.startswith(Prefix);
+}
+
+bool cocoa::isCFObjectRef(QualType T) {
+  return isRefType(T, "CF") || // Core Foundation.
+         isRefType(T, "CG") || // Core Graphics.
+         isRefType(T, "DADisk") || // Disk Arbitration API.
+         isRefType(T, "DADissenter") ||
+         isRefType(T, "DASessionRef");
+}
+
+
+bool cocoa::isCocoaObjectRef(QualType Ty) {
+  if (!Ty->isObjCObjectPointerType())
+    return false;
+  
+  const ObjCObjectPointerType *PT = Ty->getAs<ObjCObjectPointerType>();
+  
+  // Can be true for objects with the 'NSObject' attribute.
+  if (!PT)
+    return true;
+  
+  // We assume that id<..>, id, Class, and Class<..> all represent tracked
+  // objects.
+  if (PT->isObjCIdType() || PT->isObjCQualifiedIdType() ||
+      PT->isObjCClassType() || PT->isObjCQualifiedClassType())
+    return true;
+  
+  // Does the interface subclass NSObject?
+  // FIXME: We can memoize here if this gets too expensive.
+  const ObjCInterfaceDecl *ID = PT->getInterfaceDecl();
+  
+  // Assume that anything declared with a forward declaration and no
+  // @interface subclasses NSObject.
+  if (ID->isForwardDecl())
+    return true;
+  
+  for ( ; ID ; ID = ID->getSuperClass())
+    if (ID->getIdentifier()->getName() == "NSObject")
+      return true;
+  
+  return false;
+}