| //===--- 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/Basic/DiagnosticIDs.h" |
| #include "clang/Basic/FileManager.h" |
| #include "clang/Basic/SourceManager.h" |
| #include "clang/Lex/Lexer.h" |
| #include "llvm/ADT/SmallString.h" |
| #include "llvm/Support/FileSystem.h" |
| using namespace clang; |
| |
| raw_ostream &RewriteBuffer::write(raw_ostream &os) const { |
| // FIXME: eliminate the copy by writing out each chunk at a time |
| os << std::string(begin(), end()); |
| return os; |
| } |
| |
| /// \brief Return true if this character is non-new-line whitespace: |
| /// ' ', '\t', '\f', '\v', '\r'. |
| static inline bool isWhitespace(unsigned char c) { |
| switch (c) { |
| case ' ': |
| case '\t': |
| case '\f': |
| case '\v': |
| case '\r': |
| return true; |
| default: |
| return false; |
| } |
| } |
| |
| void RewriteBuffer::RemoveText(unsigned OrigOffset, unsigned Size, |
| bool removeLineIfEmpty) { |
| // 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); |
| |
| if (removeLineIfEmpty) { |
| // Find the line that the remove occurred and if it is completely empty |
| // remove the line as well. |
| |
| iterator curLineStart = begin(); |
| unsigned curLineStartOffs = 0; |
| iterator posI = begin(); |
| for (unsigned i = 0; i != RealOffset; ++i) { |
| if (*posI == '\n') { |
| curLineStart = posI; |
| ++curLineStart; |
| curLineStartOffs = i + 1; |
| } |
| ++posI; |
| } |
| |
| unsigned lineSize = 0; |
| posI = curLineStart; |
| while (posI != end() && isWhitespace(*posI)) { |
| ++posI; |
| ++lineSize; |
| } |
| if (posI != end() && *posI == '\n') { |
| Buffer.erase(curLineStartOffs, lineSize + 1/* + '\n'*/); |
| AddReplaceDelta(curLineStartOffs, -(lineSize + 1/* + '\n'*/)); |
| } |
| } |
| } |
| |
| void RewriteBuffer::InsertText(unsigned OrigOffset, StringRef Str, |
| bool InsertAfter) { |
| |
| // Nothing to insert, exit early. |
| if (Str.empty()) return; |
| |
| unsigned RealOffset = getMappedOffset(OrigOffset, InsertAfter); |
| Buffer.insert(RealOffset, Str.begin(), Str.end()); |
| |
| // Add a delta so that future changes are offset correctly. |
| AddInsertDelta(OrigOffset, Str.size()); |
| } |
| |
| /// 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, |
| StringRef NewStr) { |
| unsigned RealOffset = getMappedOffset(OrigOffset, true); |
| Buffer.erase(RealOffset, OrigLength); |
| Buffer.insert(RealOffset, NewStr.begin(), NewStr.end()); |
| if (OrigLength != NewStr.size()) |
| AddReplaceDelta(OrigOffset, NewStr.size() - 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(const CharSourceRange &Range, |
| RewriteOptions opts) 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, opts.IncludeInsertsAtEndOfRange); |
| StartOff = RB.getMappedOffset(StartOff, !opts.IncludeInsertsAtBeginOfRange); |
| } |
| |
| |
| // Adjust the end offset to the end of the last token, instead of being the |
| // start of the last token if this is a token range. |
| if (Range.isTokenRange()) |
| EndOff += Lexer::MeasureTokenLength(Range.getEnd(), *SourceMgr, *LangOpts); |
| |
| return EndOff-StartOff; |
| } |
| |
| int Rewriter::getRangeSize(SourceRange Range, RewriteOptions opts) const { |
| return getRangeSize(CharSourceRange::getTokenRange(Range), opts); |
| } |
| |
| |
| /// getRewrittenText - 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::getRewrittenText(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())); |
| |
| StringRef MB = SourceMgr->getBufferData(FID); |
| I->second.Initialize(MB.begin(), MB.end()); |
| |
| return I->second; |
| } |
| |
| /// InsertText - Insert the specified string at the specified location in the |
| /// original buffer. |
| bool Rewriter::InsertText(SourceLocation Loc, StringRef Str, |
| bool InsertAfter, bool indentNewLines) { |
| if (!isRewritable(Loc)) return true; |
| FileID FID; |
| unsigned StartOffs = getLocationOffsetAndFileID(Loc, FID); |
| |
| SmallString<128> indentedStr; |
| if (indentNewLines && Str.find('\n') != StringRef::npos) { |
| StringRef MB = SourceMgr->getBufferData(FID); |
| |
| unsigned lineNo = SourceMgr->getLineNumber(FID, StartOffs) - 1; |
| const SrcMgr::ContentCache * |
| Content = SourceMgr->getSLocEntry(FID).getFile().getContentCache(); |
| unsigned lineOffs = Content->SourceLineCache[lineNo]; |
| |
| // Find the whitespace at the start of the line. |
| StringRef indentSpace; |
| { |
| unsigned i = lineOffs; |
| while (isWhitespace(MB[i])) |
| ++i; |
| indentSpace = MB.substr(lineOffs, i-lineOffs); |
| } |
| |
| SmallVector<StringRef, 4> lines; |
| Str.split(lines, "\n"); |
| |
| for (unsigned i = 0, e = lines.size(); i != e; ++i) { |
| indentedStr += lines[i]; |
| if (i < e-1) { |
| indentedStr += '\n'; |
| indentedStr += indentSpace; |
| } |
| } |
| Str = indentedStr.str(); |
| } |
| |
| getEditBuffer(FID).InsertText(StartOffs, Str, InsertAfter); |
| return false; |
| } |
| |
| bool Rewriter::InsertTextAfterToken(SourceLocation Loc, StringRef Str) { |
| if (!isRewritable(Loc)) return true; |
| FileID FID; |
| unsigned StartOffs = getLocationOffsetAndFileID(Loc, FID); |
| RewriteOptions rangeOpts; |
| rangeOpts.IncludeInsertsAtBeginOfRange = false; |
| StartOffs += getRangeSize(SourceRange(Loc, Loc), rangeOpts); |
| getEditBuffer(FID).InsertText(StartOffs, Str, /*InsertAfter*/true); |
| return false; |
| } |
| |
| /// RemoveText - Remove the specified text region. |
| bool Rewriter::RemoveText(SourceLocation Start, unsigned Length, |
| RewriteOptions opts) { |
| if (!isRewritable(Start)) return true; |
| FileID FID; |
| unsigned StartOffs = getLocationOffsetAndFileID(Start, FID); |
| getEditBuffer(FID).RemoveText(StartOffs, Length, opts.RemoveLineIfEmpty); |
| 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, |
| StringRef NewStr) { |
| if (!isRewritable(Start)) return true; |
| FileID StartFileID; |
| unsigned StartOffs = getLocationOffsetAndFileID(Start, StartFileID); |
| |
| getEditBuffer(StartFileID).ReplaceText(StartOffs, OrigLength, NewStr); |
| return false; |
| } |
| |
| bool Rewriter::ReplaceText(SourceRange range, SourceRange replacementRange) { |
| if (!isRewritable(range.getBegin())) return true; |
| if (!isRewritable(range.getEnd())) return true; |
| if (replacementRange.isInvalid()) return true; |
| SourceLocation start = range.getBegin(); |
| unsigned origLength = getRangeSize(range); |
| unsigned newLength = getRangeSize(replacementRange); |
| FileID FID; |
| unsigned newOffs = getLocationOffsetAndFileID(replacementRange.getBegin(), |
| FID); |
| StringRef MB = SourceMgr->getBufferData(FID); |
| return ReplaceText(start, origLength, MB.substr(newOffs, newLength)); |
| } |
| |
| /// 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, 0, PrintingPolicy(*LangOpts)); |
| const std::string &Str = S.str(); |
| |
| ReplaceText(From->getLocStart(), Size, Str); |
| return false; |
| } |
| |
| std::string Rewriter::ConvertToString(Stmt *From) { |
| std::string SStr; |
| llvm::raw_string_ostream S(SStr); |
| From->printPretty(S, 0, PrintingPolicy(*LangOpts)); |
| return S.str(); |
| } |
| |
| bool Rewriter::IncreaseIndentation(CharSourceRange range, |
| SourceLocation parentIndent) { |
| if (range.isInvalid()) return true; |
| if (!isRewritable(range.getBegin())) return true; |
| if (!isRewritable(range.getEnd())) return true; |
| if (!isRewritable(parentIndent)) return true; |
| |
| FileID StartFileID, EndFileID, parentFileID; |
| unsigned StartOff, EndOff, parentOff; |
| |
| StartOff = getLocationOffsetAndFileID(range.getBegin(), StartFileID); |
| EndOff = getLocationOffsetAndFileID(range.getEnd(), EndFileID); |
| parentOff = getLocationOffsetAndFileID(parentIndent, parentFileID); |
| |
| if (StartFileID != EndFileID || StartFileID != parentFileID) |
| return true; |
| if (StartOff > EndOff) |
| return true; |
| |
| FileID FID = StartFileID; |
| StringRef MB = SourceMgr->getBufferData(FID); |
| |
| unsigned parentLineNo = SourceMgr->getLineNumber(FID, parentOff) - 1; |
| unsigned startLineNo = SourceMgr->getLineNumber(FID, StartOff) - 1; |
| unsigned endLineNo = SourceMgr->getLineNumber(FID, EndOff) - 1; |
| |
| const SrcMgr::ContentCache * |
| Content = SourceMgr->getSLocEntry(FID).getFile().getContentCache(); |
| |
| // Find where the lines start. |
| unsigned parentLineOffs = Content->SourceLineCache[parentLineNo]; |
| unsigned startLineOffs = Content->SourceLineCache[startLineNo]; |
| |
| // Find the whitespace at the start of each line. |
| StringRef parentSpace, startSpace; |
| { |
| unsigned i = parentLineOffs; |
| while (isWhitespace(MB[i])) |
| ++i; |
| parentSpace = MB.substr(parentLineOffs, i-parentLineOffs); |
| |
| i = startLineOffs; |
| while (isWhitespace(MB[i])) |
| ++i; |
| startSpace = MB.substr(startLineOffs, i-startLineOffs); |
| } |
| if (parentSpace.size() >= startSpace.size()) |
| return true; |
| if (!startSpace.startswith(parentSpace)) |
| return true; |
| |
| StringRef indent = startSpace.substr(parentSpace.size()); |
| |
| // Indent the lines between start/end offsets. |
| RewriteBuffer &RB = getEditBuffer(FID); |
| for (unsigned lineNo = startLineNo; lineNo <= endLineNo; ++lineNo) { |
| unsigned offs = Content->SourceLineCache[lineNo]; |
| unsigned i = offs; |
| while (isWhitespace(MB[i])) |
| ++i; |
| StringRef origIndent = MB.substr(offs, i-offs); |
| if (origIndent.startswith(startSpace)) |
| RB.InsertText(offs, indent, /*InsertAfter=*/false); |
| } |
| |
| return false; |
| } |
| |
| // A wrapper for a file stream that atomically overwrites the target. |
| // |
| // Creates a file output stream for a temporary file in the constructor, |
| // which is later accessible via getStream() if ok() return true. |
| // Flushes the stream and moves the temporary file to the target location |
| // in the destructor. |
| class AtomicallyMovedFile { |
| public: |
| AtomicallyMovedFile(DiagnosticsEngine &Diagnostics, StringRef Filename, |
| bool &AllWritten) |
| : Diagnostics(Diagnostics), Filename(Filename), AllWritten(AllWritten) { |
| TempFilename = Filename; |
| TempFilename += "-%%%%%%%%"; |
| int FD; |
| if (llvm::sys::fs::unique_file(TempFilename.str(), FD, TempFilename, |
| /*makeAbsolute=*/true, 0664)) { |
| AllWritten = false; |
| Diagnostics.Report(clang::diag::err_unable_to_make_temp) |
| << TempFilename; |
| } else { |
| FileStream.reset(new llvm::raw_fd_ostream(FD, /*shouldClose=*/true)); |
| } |
| } |
| |
| ~AtomicallyMovedFile() { |
| if (!ok()) return; |
| |
| FileStream->flush(); |
| #ifdef _WIN32 |
| // Win32 does not allow rename/removing opened files. |
| FileStream.reset(); |
| #endif |
| if (llvm::error_code ec = |
| llvm::sys::fs::rename(TempFilename.str(), Filename)) { |
| AllWritten = false; |
| Diagnostics.Report(clang::diag::err_unable_to_rename_temp) |
| << TempFilename << Filename << ec.message(); |
| bool existed; |
| // If the remove fails, there's not a lot we can do - this is already an |
| // error. |
| llvm::sys::fs::remove(TempFilename.str(), existed); |
| } |
| } |
| |
| bool ok() { return FileStream; } |
| llvm::raw_ostream &getStream() { return *FileStream; } |
| |
| private: |
| DiagnosticsEngine &Diagnostics; |
| StringRef Filename; |
| SmallString<128> TempFilename; |
| OwningPtr<llvm::raw_fd_ostream> FileStream; |
| bool &AllWritten; |
| }; |
| |
| bool Rewriter::overwriteChangedFiles() { |
| bool AllWritten = true; |
| for (buffer_iterator I = buffer_begin(), E = buffer_end(); I != E; ++I) { |
| const FileEntry *Entry = |
| getSourceMgr().getFileEntryForID(I->first); |
| AtomicallyMovedFile File(getSourceMgr().getDiagnostics(), Entry->getName(), |
| AllWritten); |
| if (File.ok()) { |
| I->second.write(File.getStream()); |
| } |
| } |
| return !AllWritten; |
| } |