[libclang] Introduce clang_findReferencesInFile which accepts a cursor, a file,

and a callback and finds all identifier references of the cursor in the file.

rdar://7948304

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@141277 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 315 insertions, 0 deletions

diff --git a/tools/libclang/CIndexHigh.cpp b/tools/libclang/CIndexHigh.cpp
new file mode 100644
index 0000000000..b5a05eaafc
--- /dev/null
+++ b/tools/libclang/CIndexHigh.cpp
@@ -0,0 +1,315 @@
+//===- CIndexHigh.cpp - Higher level API functions ------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "Index_Internal.h"
+#include "CXCursor.h"
+#include "CXSourceLocation.h"
+#include "CXTranslationUnit.h"
+
+#include "clang/Frontend/ASTUnit.h"
+#include "clang/AST/DeclObjC.h"
+
+using namespace clang;
+
+static void getTopOverriddenMethods(CXTranslationUnit TU,
+                                    Decl *D,
+                                    SmallVectorImpl<Decl *> &Methods) {
+  if (!isa<ObjCMethodDecl>(D) && !isa<CXXMethodDecl>(D))
+    return;
+
+  SmallVector<CXCursor, 8> Overridden;
+  cxcursor::getOverriddenCursors(cxcursor::MakeCXCursor(D, TU), Overridden);
+  
+  if (Overridden.empty()) {
+    Methods.push_back(D->getCanonicalDecl());
+    return;
+  }
+
+  for (SmallVector<CXCursor, 8>::iterator
+         I = Overridden.begin(), E = Overridden.end(); I != E; ++I)
+    getTopOverriddenMethods(TU, cxcursor::getCursorDecl(*I), Methods);
+}
+
+namespace {
+
+struct FindFileIdRefVisitData {
+  CXTranslationUnit TU;
+  FileID FID;
+  Decl *Dcl;
+  int SelectorIdIdx;
+  CXCursorAndRangeVisitor visitor;
+
+  typedef SmallVector<Decl *, 8> TopMethodsTy;
+  TopMethodsTy TopMethods;
+
+  FindFileIdRefVisitData(CXTranslationUnit TU, FileID FID,
+                         Decl *D, int selectorIdIdx,
+                         CXCursorAndRangeVisitor visitor)
+    : TU(TU), FID(FID), SelectorIdIdx(selectorIdIdx), visitor(visitor) {
+    Dcl = getCanonical(D);
+    getTopOverriddenMethods(TU, Dcl, TopMethods);
+  }
+
+  ASTContext &getASTContext() const {
+    return static_cast<ASTUnit *>(TU->TUData)->getASTContext();
+  }
+
+  /// \brief We are looking to find all semantically relevant identifiers,
+  /// so the definition of "canonical" here is different than in the AST, e.g.
+  ///
+  /// \code
+  ///   class C {
+  ///     C() {}
+  ///   };
+  /// \endcode
+  ///
+  /// we consider the canonical decl of the constructor decl to be the class
+  /// itself, so both 'C' can be highlighted.
+  Decl *getCanonical(Decl *D) const {
+    D = D->getCanonicalDecl();
+
+    if (ObjCImplDecl *ImplD = dyn_cast<ObjCImplDecl>(D))
+      return getCanonical(ImplD->getClassInterface());
+    if (CXXConstructorDecl *CXXCtorD = dyn_cast<CXXConstructorDecl>(D))
+      return getCanonical(CXXCtorD->getParent());
+    
+    return D;
+  }
+
+  bool isHit(Decl *D) const {
+    D = getCanonical(D);
+    if (D == Dcl)
+      return true;
+
+    if (isa<ObjCMethodDecl>(D) || isa<CXXMethodDecl>(D))
+      return isOverriddingMethod(D);
+
+    return false;
+  }
+
+private:
+  bool isOverriddingMethod(Decl *D) const {
+    if (std::find(TopMethods.begin(), TopMethods.end(), D) !=
+          TopMethods.end())
+      return true;
+
+    TopMethodsTy methods;
+    getTopOverriddenMethods(TU, D, methods);
+    for (TopMethodsTy::iterator
+           I = methods.begin(), E = methods.end(); I != E; ++I) {
+      if (std::find(TopMethods.begin(), TopMethods.end(), *I) !=
+            TopMethods.end())
+        return true;
+    }
+
+    return false;
+  }
+};
+
+} // end anonymous namespace.
+
+/// \brief For a macro \arg Loc, returns the file spelling location and sets
+/// to \arg isMacroArg whether the spelling resides inside a macro definition or
+/// a macro argument.
+static SourceLocation getFileSpellingLoc(SourceManager &SM,
+                                         SourceLocation Loc,
+                                         bool &isMacroArg) {
+  assert(Loc.isMacroID());
+  SourceLocation SpellLoc = SM.getImmediateSpellingLoc(Loc);
+  if (SpellLoc.isMacroID())
+    return getFileSpellingLoc(SM, SpellLoc, isMacroArg);
+  
+  isMacroArg = SM.isMacroArgExpansion(Loc);
+  return SpellLoc;
+}
+
+static enum CXChildVisitResult findFileIdRefVisit(CXCursor cursor,
+                                                  CXCursor parent,
+                                                  CXClientData client_data) {
+  CXCursor declCursor = clang_getCursorReferenced(cursor);
+  if (!clang_isDeclaration(declCursor.kind))
+    return CXChildVisit_Recurse;
+
+  Decl *D = cxcursor::getCursorDecl(declCursor);
+  FindFileIdRefVisitData *data = (FindFileIdRefVisitData *)client_data;
+  if (data->isHit(D)) {
+    cursor = cxcursor::getSelectorIdentifierCursor(data->SelectorIdIdx, cursor);
+
+    // We are looking for identifiers to highlight so for objc methods (and
+    // not a parameter) we can only highlight the selector identifiers.
+    if ((cursor.kind == CXCursor_ObjCClassMethodDecl ||
+         cursor.kind == CXCursor_ObjCInstanceMethodDecl) &&
+         cxcursor::getSelectorIdentifierIndex(cursor) == -1)
+      return CXChildVisit_Recurse;
+
+    if (clang_isExpression(cursor.kind)) {
+      if (cursor.kind == CXCursor_DeclRefExpr ||
+          cursor.kind == CXCursor_MemberRefExpr) {
+        // continue..
+
+      } else if (cursor.kind == CXCursor_ObjCMessageExpr &&
+                 cxcursor::getSelectorIdentifierIndex(cursor) != -1) {
+        // continue..
+                
+      } else
+        return CXChildVisit_Recurse;
+    }
+
+    SourceLocation
+      Loc = cxloc::translateSourceLocation(clang_getCursorLocation(cursor));
+    SourceLocation SelIdLoc = cxcursor::getSelectorIdentifierLoc(cursor);
+    if (SelIdLoc.isValid())
+      Loc = SelIdLoc;
+
+    SourceManager &SM = data->getASTContext().getSourceManager();
+    bool isInMacroDef = false;
+    if (Loc.isMacroID()) {
+      bool isMacroArg;
+      Loc = getFileSpellingLoc(SM, Loc, isMacroArg);
+      isInMacroDef = !isMacroArg;
+    }
+
+    // We are looking for identifiers in a specific file.
+    std::pair<FileID, unsigned> LocInfo = SM.getDecomposedLoc(Loc);
+    if (LocInfo.first != data->FID)
+      return CXChildVisit_Recurse;
+
+    if (isInMacroDef) {
+      // FIXME: For a macro definition make sure that all expansions
+      // of it expand to the same reference before allowing to point to it.
+      Loc = SourceLocation();
+    }
+
+    data->visitor.visit(data->visitor.context, cursor,
+                        cxloc::translateSourceRange(D->getASTContext(), Loc));
+  }
+  return CXChildVisit_Recurse;
+}
+
+static void findIdRefsInFile(CXTranslationUnit TU, CXCursor declCursor,
+                           const FileEntry *File,
+                           CXCursorAndRangeVisitor Visitor) {
+  assert(clang_isDeclaration(declCursor.kind));
+  ASTUnit *Unit = static_cast<ASTUnit*>(TU->TUData);
+  ASTContext &Ctx = Unit->getASTContext();
+  SourceManager &SM = Unit->getSourceManager();
+
+  FileID FID = SM.translateFile(File);
+  Decl *Dcl = cxcursor::getCursorDecl(declCursor);
+  FindFileIdRefVisitData data(TU, FID, Dcl,
+                              cxcursor::getSelectorIdentifierIndex(declCursor),
+                              Visitor);
+
+  if (DeclContext *DC = Dcl->getParentFunctionOrMethod()) {
+    clang_visitChildren(cxcursor::MakeCXCursor(cast<Decl>(DC), TU),
+                        findFileIdRefVisit, &data);
+    return;
+  }
+  
+  if (FID == SM.getMainFileID() && !Unit->isMainFileAST()) {
+    SourceLocation FileLoc = SM.getLocForStartOfFile(FID);
+    TranslationUnitDecl *TUD = Ctx.getTranslationUnitDecl();
+    CXCursor TUCursor = clang_getTranslationUnitCursor(TU);
+    for (DeclContext::decl_iterator
+           I = TUD->noload_decls_begin(), E = TUD->noload_decls_end();
+         I != E; ++I) {
+      Decl *D = *I;
+
+      SourceRange R = D->getSourceRange();
+      if (R.isInvalid())
+        continue;
+      if (SM.isBeforeInTranslationUnit(R.getEnd(), FileLoc))
+        continue;
+
+      if (TagDecl *TD = dyn_cast<TagDecl>(D))
+        if (!TD->isFreeStanding())
+          continue;
+
+      CXCursor CurCursor = cxcursor::MakeCXCursor(D, TU);
+      findFileIdRefVisit(CurCursor, TUCursor, &data);
+      clang_visitChildren(CurCursor, findFileIdRefVisit, &data);
+    }
+    return;
+  }
+
+  clang_visitChildren(clang_getTranslationUnitCursor(TU),
+                      findFileIdRefVisit, &data);
+}
+
+
+//===----------------------------------------------------------------------===//
+// libclang public APIs.
+//===----------------------------------------------------------------------===//
+
+extern "C" {
+
+void clang_findReferencesInFile(CXCursor cursor, CXFile file,
+                                CXCursorAndRangeVisitor visitor) {
+  bool Logging = ::getenv("LIBCLANG_LOGGING");
+
+  if (clang_Cursor_isNull(cursor)) {
+    if (Logging)
+      llvm::errs() << "clang_findReferencesInFile: Null cursor\n";
+    return;
+  }
+  if (!file) {
+    if (Logging)
+      llvm::errs() << "clang_findReferencesInFile: Null file\n";
+    return;
+  }
+  if (!visitor.visit) {
+    if (Logging)
+      llvm::errs() << "clang_findReferencesInFile: Null visitor\n";
+    return;
+  }
+
+  // We are interested in semantics of identifiers so for C++ constructor exprs
+  // prefer type references, e.g.:
+  //
+  //  return MyStruct();
+  //
+  // for 'MyStruct' we'll have a cursor pointing at the constructor decl but
+  // we are actually interested in the type declaration.
+  cursor = cxcursor::getTypeRefCursor(cursor);
+
+  CXCursor refCursor = clang_getCursorReferenced(cursor);
+
+  if (!clang_isDeclaration(refCursor.kind)) {
+    if (Logging)
+      llvm::errs() << "clang_findReferencesInFile: cursor is not referencing a "
+                      "declaration\n";
+    return;
+  }
+
+  ASTUnit *CXXUnit = cxcursor::getCursorASTUnit(cursor);
+  ASTUnit::ConcurrencyCheck Check(*CXXUnit);
+
+  findIdRefsInFile(cxcursor::getCursorTU(cursor),
+                   refCursor,
+                   static_cast<const FileEntry *>(file),
+                   visitor);
+}
+
+static enum CXVisitorResult _visitCursorAndRange(void *context,
+                                                 CXCursor cursor,
+                                                 CXSourceRange range) {
+  CXCursorAndRangeVisitorBlock block = (CXCursorAndRangeVisitorBlock)context;
+  return INVOKE_BLOCK2(block, cursor, range);
+}
+
+void clang_findReferencesInFileWithBlock(CXCursor cursor,
+                                         CXFile file,
+                                         CXCursorAndRangeVisitorBlock block) {
+  CXCursorAndRangeVisitor visitor = { block,
+                                      block ? _visitCursorAndRange : 0 };
+  return clang_findReferencesInFile(cursor, file, visitor);
+}
+
+} // end: extern "C"
+