1 files changed, 295 insertions, 3 deletions
diff --git a/lib/Parse/RAIIObjectsForParser.h b/lib/Parse/RAIIObjectsForParser.h
index ef17aee..455c4af 100644
--- a/lib/Parse/RAIIObjectsForParser.h
+++ b/lib/Parse/RAIIObjectsForParser.h
@@ -16,13 +16,230 @@
 #define LLVM_CLANG_PARSE_RAII_OBJECTS_FOR_PARSER_H
 
 #include "clang/Parse/ParseDiagnostic.h"
+#include "clang/Parse/Parser.h"
+#include "clang/Sema/DelayedDiagnostic.h"
+#include "clang/Sema/Sema.h"
 
 namespace clang {
-  // TODO: move ParsingDeclRAIIObject here.
   // TODO: move ParsingClassDefinition here.
   // TODO: move TentativeParsingAction here.
-  
-  
+
+  /// \brief A RAII object used to temporarily suppress access-like
+  /// checking.  Access-like checks are those associated with
+  /// controlling the use of a declaration, like C++ access control
+  /// errors and deprecation warnings.  They are contextually
+  /// dependent, in that they can only be resolved with full
+  /// information about what's being declared.  They are also
+  /// suppressed in certain contexts, like the template arguments of
+  /// an explicit instantiation.  However, those suppression contexts
+  /// cannot necessarily be fully determined in advance;  for
+  /// example, something starting like this:
+  ///   template <> class std::vector<A::PrivateType>
+  /// might be the entirety of an explicit instantiation:
+  ///   template <> class std::vector<A::PrivateType>;
+  /// or just an elaborated type specifier:
+  ///   template <> class std::vector<A::PrivateType> make_vector<>();
+  /// Therefore this class collects all the diagnostics and permits
+  /// them to be re-delayed in a new context.
+  class SuppressAccessChecks {
+    Sema &S;
+    sema::DelayedDiagnosticPool DiagnosticPool;
+    Sema::ParsingDeclState State;
+    bool Active;
+
+  public:
+    /// Begin suppressing access-like checks 
+    SuppressAccessChecks(Parser &P, bool activate = true)
+        : S(P.getActions()), DiagnosticPool(NULL) {
+      if (activate) {
+        State = S.PushParsingDeclaration(DiagnosticPool);
+        Active = true;
+      } else {
+        Active = false;
+      }
+    }
+
+    void done() {
+      assert(Active && "trying to end an inactive suppression");
+      S.PopParsingDeclaration(State, NULL);
+      Active = false;
+    }
+
+    void redelay() {
+      assert(!Active && "redelaying without having ended first");
+      if (!DiagnosticPool.pool_empty())
+        S.redelayDiagnostics(DiagnosticPool);
+      assert(DiagnosticPool.pool_empty());
+    }
+
+    ~SuppressAccessChecks() {
+      if (Active) done();
+    }
+  };
+
+  /// \brief RAII object used to inform the actions that we're
+  /// currently parsing a declaration.  This is active when parsing a
+  /// variable's initializer, but not when parsing the body of a
+  /// class or function definition.
+  class ParsingDeclRAIIObject {
+    Sema &Actions;
+    sema::DelayedDiagnosticPool DiagnosticPool;
+    Sema::ParsingDeclState State;
+    bool Popped;
+
+    // Do not implement.
+    ParsingDeclRAIIObject(const ParsingDeclRAIIObject &other);
+    ParsingDeclRAIIObject &operator=(const ParsingDeclRAIIObject &other);
+
+  public:
+    enum NoParent_t { NoParent };
+    ParsingDeclRAIIObject(Parser &P, NoParent_t _)
+        : Actions(P.getActions()), DiagnosticPool(NULL) {
+      push();
+    }
+
+    /// Creates a RAII object whose pool is optionally parented by another.
+    ParsingDeclRAIIObject(Parser &P,
+                          const sema::DelayedDiagnosticPool *parentPool)
+        : Actions(P.getActions()), DiagnosticPool(parentPool) {
+      push();
+    }
+
+    /// Creates a RAII object and, optionally, initialize its
+    /// diagnostics pool by stealing the diagnostics from another
+    /// RAII object (which is assumed to be the current top pool).
+    ParsingDeclRAIIObject(Parser &P, ParsingDeclRAIIObject *other)
+        : Actions(P.getActions()),
+          DiagnosticPool(other ? other->DiagnosticPool.getParent() : NULL) {
+      if (other) {
+        DiagnosticPool.steal(other->DiagnosticPool);
+        other->abort();
+      }
+      push();
+    }
+
+    ~ParsingDeclRAIIObject() {
+      abort();
+    }
+
+    sema::DelayedDiagnosticPool &getDelayedDiagnosticPool() {
+      return DiagnosticPool;
+    }
+    const sema::DelayedDiagnosticPool &getDelayedDiagnosticPool() const {
+      return DiagnosticPool;
+    }
+
+    /// Resets the RAII object for a new declaration.
+    void reset() {
+      abort();
+      push();
+    }
+
+    /// Signals that the context was completed without an appropriate
+    /// declaration being parsed.
+    void abort() {
+      pop(0);
+    }
+
+    void complete(Decl *D) {
+      assert(!Popped && "ParsingDeclaration has already been popped!");
+      pop(D);
+    }
+
+    /// Unregister this object from Sema, but remember all the
+    /// diagnostics that were emitted into it.
+    void abortAndRemember() {
+      pop(0);
+    }
+
+  private:
+    void push() {
+      State = Actions.PushParsingDeclaration(DiagnosticPool);
+      Popped = false;
+    }
+
+    void pop(Decl *D) {
+      if (!Popped) {
+        Actions.PopParsingDeclaration(State, D);
+        Popped = true;
+      }
+    }
+  };
+
+  /// A class for parsing a DeclSpec.
+  class ParsingDeclSpec : public DeclSpec {
+    ParsingDeclRAIIObject ParsingRAII;
+
+  public:
+    ParsingDeclSpec(Parser &P)
+      : DeclSpec(P.getAttrFactory()),
+        ParsingRAII(P, ParsingDeclRAIIObject::NoParent) {}
+    ParsingDeclSpec(Parser &P, ParsingDeclRAIIObject *RAII)
+      : DeclSpec(P.getAttrFactory()),
+        ParsingRAII(P, RAII) {}
+
+    const sema::DelayedDiagnosticPool &getDelayedDiagnosticPool() const {
+      return ParsingRAII.getDelayedDiagnosticPool();
+    }
+
+    void complete(Decl *D) {
+      ParsingRAII.complete(D);
+    }
+
+    void abort() {
+      ParsingRAII.abort();
+    }
+  };
+
+  /// A class for parsing a declarator.
+  class ParsingDeclarator : public Declarator {
+    ParsingDeclRAIIObject ParsingRAII;
+
+  public:
+    ParsingDeclarator(Parser &P, const ParsingDeclSpec &DS, TheContext C)
+      : Declarator(DS, C), ParsingRAII(P, &DS.getDelayedDiagnosticPool()) {
+    }
+
+    const ParsingDeclSpec &getDeclSpec() const {
+      return static_cast<const ParsingDeclSpec&>(Declarator::getDeclSpec());
+    }
+
+    ParsingDeclSpec &getMutableDeclSpec() const {
+      return const_cast<ParsingDeclSpec&>(getDeclSpec());
+    }
+
+    void clear() {
+      Declarator::clear();
+      ParsingRAII.reset();
+    }
+
+    void complete(Decl *D) {
+      ParsingRAII.complete(D);
+    }
+  };
+
+  /// A class for parsing a field declarator.
+  class ParsingFieldDeclarator : public FieldDeclarator {
+    ParsingDeclRAIIObject ParsingRAII;
+
+  public:
+    ParsingFieldDeclarator(Parser &P, const ParsingDeclSpec &DS)
+      : FieldDeclarator(DS), ParsingRAII(P, &DS.getDelayedDiagnosticPool()) {
+    }
+
+    const ParsingDeclSpec &getDeclSpec() const {
+      return static_cast<const ParsingDeclSpec&>(D.getDeclSpec());
+    }
+
+    ParsingDeclSpec &getMutableDeclSpec() const {
+      return const_cast<ParsingDeclSpec&>(getDeclSpec());
+    }
+
+    void complete(Decl *D) {
+      ParsingRAII.complete(D);
+    }
+  };
+
   /// ExtensionRAIIObject - This saves the state of extension warnings when
   /// constructed and disables them.  When destructed, it restores them back to
   /// the way they used to be.  This is used to handle __extension__ in the
@@ -137,6 +354,81 @@ namespace clang {
     }
   };
 
+  /// \brief RAII class that helps handle the parsing of an open/close delimiter
+  /// pair, such as braces { ... } or parentheses ( ... ).
+  class BalancedDelimiterTracker : public GreaterThanIsOperatorScope {
+    Parser& P;
+    tok::TokenKind Kind, Close;
+    SourceLocation (Parser::*Consumer)();
+    SourceLocation LOpen, LClose;
+    
+    unsigned short &getDepth() {
+      switch (Kind) {
+        case tok::l_brace: return P.BraceCount;
+        case tok::l_square: return P.BracketCount;
+        case tok::l_paren: return P.ParenCount;
+        default: llvm_unreachable("Wrong token kind");
+      }
+    }
+    
+    enum { MaxDepth = 256 };
+    
+    bool diagnoseOverflow();
+    bool diagnoseMissingClose();
+    
+  public:
+    BalancedDelimiterTracker(Parser& p, tok::TokenKind k)
+      : GreaterThanIsOperatorScope(p.GreaterThanIsOperator, true),
+        P(p), Kind(k)
+    {
+      switch (Kind) {
+        default: llvm_unreachable("Unexpected balanced token");
+        case tok::l_brace:
+          Close = tok::r_brace; 
+          Consumer = &Parser::ConsumeBrace;
+          break;
+        case tok::l_paren:
+          Close = tok::r_paren; 
+          Consumer = &Parser::ConsumeParen;
+          break;
+          
+        case tok::l_square:
+          Close = tok::r_square; 
+          Consumer = &Parser::ConsumeBracket;
+          break;
+      }      
+    }
+    
+    SourceLocation getOpenLocation() const { return LOpen; }
+    SourceLocation getCloseLocation() const { return LClose; }
+    SourceRange getRange() const { return SourceRange(LOpen, LClose); }
+    
+    bool consumeOpen() {
+      if (!P.Tok.is(Kind))
+        return true;
+      
+      if (getDepth() < MaxDepth) {
+        LOpen = (P.*Consumer)();
+        return false;
+      }
+      
+      return diagnoseOverflow();
+    }
+    
+    bool expectAndConsume(unsigned DiagID,
+                          const char *Msg = "",
+                          tok::TokenKind SkipToTok = tok::unknown);
+    bool consumeClose() {
+      if (P.Tok.is(Close)) {
+        LClose = (P.*Consumer)();
+        return false;
+      } 
+      
+      return diagnoseMissingClose();
+    }
+    void skipToEnd();
+  };
+
 } // end namespace clang
 
 #endif