| //===--- Rewriter.cpp - Code rewriting interface --------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file defines the Rewriter class, which is used for code |
| // transformations. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "clang/Rewrite/Rewriter.h" |
| #include "clang/AST/Stmt.h" |
| #include "clang/AST/Decl.h" |
| #include "clang/Lex/Lexer.h" |
| #include "clang/Basic/SourceManager.h" |
| #include "llvm/Support/raw_ostream.h" |
| using namespace clang; |
| |
| void RewriteBuffer::RemoveText(unsigned OrigOffset, unsigned Size) { |
| // Nothing to remove, exit early. |
| if (Size == 0) return; |
| |
| unsigned RealOffset = getMappedOffset(OrigOffset, true); |
| assert(RealOffset+Size < Buffer.size() && "Invalid location"); |
| |
| // Remove the dead characters. |
| Buffer.erase(RealOffset, Size); |
| |
| // Add a delta so that future changes are offset correctly. |
| AddReplaceDelta(OrigOffset, -Size); |
| } |
| |
| void RewriteBuffer::InsertText(unsigned OrigOffset, |
| const char *StrData, unsigned StrLen, |
| bool InsertAfter) { |
| |
| // Nothing to insert, exit early. |
| if (StrLen == 0) return; |
| |
| unsigned RealOffset = getMappedOffset(OrigOffset, InsertAfter); |
| Buffer.insert(RealOffset, StrData, StrData+StrLen); |
| |
| // Add a delta so that future changes are offset correctly. |
| AddInsertDelta(OrigOffset, StrLen); |
| } |
| |
| /// ReplaceText - This method replaces a range of characters in the input |
| /// buffer with a new string. This is effectively a combined "remove+insert" |
| /// operation. |
| void RewriteBuffer::ReplaceText(unsigned OrigOffset, unsigned OrigLength, |
| const char *NewStr, unsigned NewLength) { |
| unsigned RealOffset = getMappedOffset(OrigOffset, true); |
| Buffer.erase(RealOffset, OrigLength); |
| Buffer.insert(RealOffset, NewStr, NewStr+NewLength); |
| if (OrigLength != NewLength) |
| AddReplaceDelta(OrigOffset, NewLength-OrigLength); |
| } |
| |
| |
| //===----------------------------------------------------------------------===// |
| // Rewriter class |
| //===----------------------------------------------------------------------===// |
| |
| /// getRangeSize - Return the size in bytes of the specified range if they |
| /// are in the same file. If not, this returns -1. |
| int Rewriter::getRangeSize(SourceRange Range) const { |
| if (!isRewritable(Range.getBegin()) || |
| !isRewritable(Range.getEnd())) return -1; |
| |
| FileID StartFileID, EndFileID; |
| unsigned StartOff, EndOff; |
| |
| StartOff = getLocationOffsetAndFileID(Range.getBegin(), StartFileID); |
| EndOff = getLocationOffsetAndFileID(Range.getEnd(), EndFileID); |
| |
| if (StartFileID != EndFileID) |
| return -1; |
| |
| // If edits have been made to this buffer, the delta between the range may |
| // have changed. |
| std::map<FileID, RewriteBuffer>::const_iterator I = |
| RewriteBuffers.find(StartFileID); |
| if (I != RewriteBuffers.end()) { |
| const RewriteBuffer &RB = I->second; |
| EndOff = RB.getMappedOffset(EndOff, true); |
| StartOff = RB.getMappedOffset(StartOff); |
| } |
| |
| |
| // Adjust the end offset to the end of the last token, instead of being the |
| // start of the last token. |
| EndOff += Lexer::MeasureTokenLength(Range.getEnd(), *SourceMgr, *LangOpts); |
| |
| return EndOff-StartOff; |
| } |
| |
| /// getRewritenText - Return the rewritten form of the text in the specified |
| /// range. If the start or end of the range was unrewritable or if they are |
| /// in different buffers, this returns an empty string. |
| /// |
| /// Note that this method is not particularly efficient. |
| /// |
| std::string Rewriter::getRewritenText(SourceRange Range) const { |
| if (!isRewritable(Range.getBegin()) || |
| !isRewritable(Range.getEnd())) |
| return ""; |
| |
| FileID StartFileID, EndFileID; |
| unsigned StartOff, EndOff; |
| StartOff = getLocationOffsetAndFileID(Range.getBegin(), StartFileID); |
| EndOff = getLocationOffsetAndFileID(Range.getEnd(), EndFileID); |
| |
| if (StartFileID != EndFileID) |
| return ""; // Start and end in different buffers. |
| |
| // If edits have been made to this buffer, the delta between the range may |
| // have changed. |
| std::map<FileID, RewriteBuffer>::const_iterator I = |
| RewriteBuffers.find(StartFileID); |
| if (I == RewriteBuffers.end()) { |
| // If the buffer hasn't been rewritten, just return the text from the input. |
| const char *Ptr = SourceMgr->getCharacterData(Range.getBegin()); |
| |
| // Adjust the end offset to the end of the last token, instead of being the |
| // start of the last token. |
| EndOff += Lexer::MeasureTokenLength(Range.getEnd(), *SourceMgr, *LangOpts); |
| return std::string(Ptr, Ptr+EndOff-StartOff); |
| } |
| |
| const RewriteBuffer &RB = I->second; |
| EndOff = RB.getMappedOffset(EndOff, true); |
| StartOff = RB.getMappedOffset(StartOff); |
| |
| // Adjust the end offset to the end of the last token, instead of being the |
| // start of the last token. |
| EndOff += Lexer::MeasureTokenLength(Range.getEnd(), *SourceMgr, *LangOpts); |
| |
| // Advance the iterators to the right spot, yay for linear time algorithms. |
| RewriteBuffer::iterator Start = RB.begin(); |
| std::advance(Start, StartOff); |
| RewriteBuffer::iterator End = Start; |
| std::advance(End, EndOff-StartOff); |
| |
| return std::string(Start, End); |
| } |
| |
| unsigned Rewriter::getLocationOffsetAndFileID(SourceLocation Loc, |
| FileID &FID) const { |
| assert(Loc.isValid() && "Invalid location"); |
| std::pair<FileID,unsigned> V = SourceMgr->getDecomposedLoc(Loc); |
| FID = V.first; |
| return V.second; |
| } |
| |
| |
| /// getEditBuffer - Get or create a RewriteBuffer for the specified FileID. |
| /// |
| RewriteBuffer &Rewriter::getEditBuffer(FileID FID) { |
| std::map<FileID, RewriteBuffer>::iterator I = |
| RewriteBuffers.lower_bound(FID); |
| if (I != RewriteBuffers.end() && I->first == FID) |
| return I->second; |
| I = RewriteBuffers.insert(I, std::make_pair(FID, RewriteBuffer())); |
| |
| std::pair<const char*, const char*> MB = SourceMgr->getBufferData(FID); |
| I->second.Initialize(MB.first, MB.second); |
| |
| return I->second; |
| } |
| |
| /// InsertText - Insert the specified string at the specified location in the |
| /// original buffer. |
| bool Rewriter::InsertText(SourceLocation Loc, const char *StrData, |
| unsigned StrLen, bool InsertAfter) { |
| if (!isRewritable(Loc)) return true; |
| FileID FID; |
| unsigned StartOffs = getLocationOffsetAndFileID(Loc, FID); |
| getEditBuffer(FID).InsertText(StartOffs, StrData, StrLen, InsertAfter); |
| return false; |
| } |
| |
| /// RemoveText - Remove the specified text region. |
| bool Rewriter::RemoveText(SourceLocation Start, unsigned Length) { |
| if (!isRewritable(Start)) return true; |
| FileID FID; |
| unsigned StartOffs = getLocationOffsetAndFileID(Start, FID); |
| getEditBuffer(FID).RemoveText(StartOffs, Length); |
| return false; |
| } |
| |
| /// ReplaceText - This method replaces a range of characters in the input |
| /// buffer with a new string. This is effectively a combined "remove/insert" |
| /// operation. |
| bool Rewriter::ReplaceText(SourceLocation Start, unsigned OrigLength, |
| const char *NewStr, unsigned NewLength) { |
| if (!isRewritable(Start)) return true; |
| FileID StartFileID; |
| unsigned StartOffs = getLocationOffsetAndFileID(Start, StartFileID); |
| |
| getEditBuffer(StartFileID).ReplaceText(StartOffs, OrigLength, |
| NewStr, NewLength); |
| return false; |
| } |
| |
| /// ReplaceStmt - This replaces a Stmt/Expr with another, using the pretty |
| /// printer to generate the replacement code. This returns true if the input |
| /// could not be rewritten, or false if successful. |
| bool Rewriter::ReplaceStmt(Stmt *From, Stmt *To) { |
| // Measaure the old text. |
| int Size = getRangeSize(From->getSourceRange()); |
| if (Size == -1) |
| return true; |
| |
| // Get the new text. |
| std::string SStr; |
| llvm::raw_string_ostream S(SStr); |
| To->printPretty(S); |
| const std::string &Str = S.str(); |
| |
| ReplaceText(From->getLocStart(), Size, &Str[0], Str.size()); |
| return false; |
| } |
| |
| |