Teach CIndex's cursor visitor to restrict its traversal to a specific

region of interest (if provided). Implement clang_getCursor() in terms
of this traversal rather than using the Index library; the unified
cursor visitor is more complete, and will be The Way Forward.

Minor other tweaks needed to make this work:
  - Extend Preprocessor::getLocForEndOfToken() to accept an offset
  from the end, making it easy to move to the last character in the
  token (rather than just past the end of the token).
  - In Lexer::MeasureTokenLength(), the length of whitespace is zero.

llvm-svn: 94200

1 files changed, 7 insertions, 11 deletions

diff --git a/clang/lib/Lex/Preprocessor.cpp b/clang/lib/Lex/Preprocessor.cpp
index 586202bccfe..5689baaac65 100644
--- a/clang/lib/Lex/Preprocessor.cpp
+++ b/clang/lib/Lex/Preprocessor.cpp
@@ -429,21 +429,17 @@ SourceLocation Preprocessor::AdvanceToTokenCharacter(SourceLocation TokStart,
   return TokStart.getFileLocWithOffset(PhysOffset);
 }
 
-/// \brief Computes the source location just past the end of the
-/// token at this source location.
-///
-/// This routine can be used to produce a source location that
-/// points just past the end of the token referenced by \p Loc, and
-/// is generally used when a diagnostic needs to point just after a
-/// token where it expected something different that it received. If
-/// the returned source location would not be meaningful (e.g., if
-/// it points into a macro), this routine returns an invalid
-/// source location.
-SourceLocation Preprocessor::getLocForEndOfToken(SourceLocation Loc) {
+SourceLocation Preprocessor::getLocForEndOfToken(SourceLocation Loc, 
+                                                 unsigned Offset) {
   if (Loc.isInvalid() || !Loc.isFileID())
     return SourceLocation();
 
   unsigned Len = Lexer::MeasureTokenLength(Loc, getSourceManager(), Features);
+  if (Len > Offset)
+    Len = Len - Offset;
+  else
+    return Loc;
+  
   return AdvanceToTokenCharacter(Loc, Len);
 }