external/bsd/llvm/dist/clang/lib/Rewrite/TokenRewriter.cpp

   1 //===--- TokenRewriter.cpp - Token-based code rewriting interface ---------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 //  This file implements the TokenRewriter class, which is used for code
  11 //  transformations.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "clang/Rewrite/Core/TokenRewriter.h"
  16 #include "clang/Basic/SourceManager.h"
  17 #include "clang/Lex/Lexer.h"
  18 #include "clang/Lex/ScratchBuffer.h"
  19 using namespace clang;
  20
  21 TokenRewriter::TokenRewriter(FileID FID, SourceManager &SM,
  22                              const LangOptions &LangOpts) {
  23   ScratchBuf.reset(new ScratchBuffer(SM));
  24
  25   // Create a lexer to lex all the tokens of the main file in raw mode.
  26   const llvm::MemoryBuffer *FromFile = SM.getBuffer(FID);
  27   Lexer RawLex(FID, FromFile, SM, LangOpts);
  28
  29   // Return all comments and whitespace as tokens.
  30   RawLex.SetKeepWhitespaceMode(true);
  31
  32   // Lex the file, populating our datastructures.
  33   Token RawTok;
  34   RawLex.LexFromRawLexer(RawTok);
  35   while (RawTok.isNot(tok::eof)) {
  36 #if 0
  37     if (Tok.is(tok::raw_identifier)) {
  38       // Look up the identifier info for the token.  This should use
  39       // IdentifierTable directly instead of PP.
  40       PP.LookUpIdentifierInfo(Tok);
  41     }
  42 #endif
  43
  44     AddToken(RawTok, TokenList.end());
  45     RawLex.LexFromRawLexer(RawTok);
  46   }
  47 }
  48
  49 TokenRewriter::~TokenRewriter() {
  50 }
  51
  52
  53 /// RemapIterator - Convert from token_iterator (a const iterator) to
  54 /// TokenRefTy (a non-const iterator).
  55 TokenRewriter::TokenRefTy TokenRewriter::RemapIterator(token_iterator I) {
  56   if (I == token_end()) return TokenList.end();
  57
  58   // FIXME: This is horrible, we should use our own list or something to avoid
  59   // this.
  60   std::map<SourceLocation, TokenRefTy>::iterator MapIt =
  61     TokenAtLoc.find(I->getLocation());
  62   assert(MapIt != TokenAtLoc.end() && "iterator not in rewriter?");
  63   return MapIt->second;
  64 }
  65
  66
  67 /// AddToken - Add the specified token into the Rewriter before the other
  68 /// position.
  69 TokenRewriter::TokenRefTy
  70 TokenRewriter::AddToken(const Token &T, TokenRefTy Where) {
  71   Where = TokenList.insert(Where, T);
  72
  73   bool InsertSuccess = TokenAtLoc.insert(std::make_pair(T.getLocation(),
  74                                                         Where)).second;
  75   assert(InsertSuccess && "Token location already in rewriter!");
  76   (void)InsertSuccess;
  77   return Where;
  78 }
  79
  80
  81 TokenRewriter::token_iterator
  82 TokenRewriter::AddTokenBefore(token_iterator I, const char *Val) {
  83   unsigned Len = strlen(Val);
  84
  85   // Plop the string into the scratch buffer, then create a token for this
  86   // string.
  87   Token Tok;
  88   Tok.startToken();
  89   const char *Spelling;
  90   Tok.setLocation(ScratchBuf->getToken(Val, Len, Spelling));
  91   Tok.setLength(Len);
  92
  93   // TODO: Form a whole lexer around this and relex the token!  For now, just
  94   // set kind to tok::unknown.
  95   Tok.setKind(tok::unknown);
  96
  97   return AddToken(Tok, RemapIterator(I));
  98 }
  99