lib/Driver/HTMLDiagnostics.cpp - platform/external/clang - Gitiles

 //===--- HTMLDiagnostics.cpp - HTML Diagnostics for Paths ----*- C++ -*-===//
 //
 //                     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 HTMLDiagnostics object.
 //
 //===----------------------------------------------------------------------===//

 #include "clang/Driver/PathDiagnosticClients.h"
 #include "clang/Analysis/PathDiagnostic.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/Decl.h"
 #include "clang/Basic/SourceManager.h"
 #include "clang/Basic/FileManager.h"
 #include "clang/Rewrite/Rewriter.h"
 #include "clang/Rewrite/HTMLRewrite.h"
 #include "clang/Lex/Lexer.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/Streams.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/System/Path.h"
 #include <fstream>
 using namespace clang;

 //===----------------------------------------------------------------------===//
 // Boilerplate.
 //===----------------------------------------------------------------------===//

 namespace {

 class VISIBILITY_HIDDEN HTMLDiagnostics : public PathDiagnosticClient {
   llvm::sys::Path Directory, FilePrefix;
   bool createdDir, noDir;
   Preprocessor* PP;
   PreprocessorFactory* PPF;
   std::vector<const PathDiagnostic*> BatchedDiags;
 public:
   HTMLDiagnostics(const std::string& prefix, Preprocessor* pp,
                   PreprocessorFactory* ppf);

   virtual ~HTMLDiagnostics();

   virtual void HandlePathDiagnostic(const PathDiagnostic* D);

   void HandlePiece(Rewriter& R, FileID BugFileID,
                    const PathDiagnosticPiece& P, unsigned num, unsigned max);

   void HighlightRange(Rewriter& R, FileID BugFileID, SourceRange Range);

   void ReportDiag(const PathDiagnostic& D);
 };

 } // end anonymous namespace

 HTMLDiagnostics::HTMLDiagnostics(const std::string& prefix, Preprocessor* pp,
                                  PreprocessorFactory* ppf)
   : Directory(prefix), FilePrefix(prefix), createdDir(false), noDir(false),
     PP(pp), PPF(ppf) {

   // All html files begin with "report"
   FilePrefix.appendComponent("report");
 }

 PathDiagnosticClient*
 clang::CreateHTMLDiagnosticClient(const std::string& prefix, Preprocessor* PP,
                                   PreprocessorFactory* PPF) {

   return new HTMLDiagnostics(prefix, PP, PPF);
 }

 //===----------------------------------------------------------------------===//
 // Report processing.
 //===----------------------------------------------------------------------===//

 void HTMLDiagnostics::HandlePathDiagnostic(const PathDiagnostic* D) {
   if (!D)
     return;

   if (D->empty()) {
     delete D;
     return;
   }

   BatchedDiags.push_back(D);
 }

 HTMLDiagnostics::~HTMLDiagnostics() {

   while (!BatchedDiags.empty()) {
     const PathDiagnostic* D = BatchedDiags.back();
     BatchedDiags.pop_back();
     ReportDiag(*D);
     delete D;
   }
 }

 void HTMLDiagnostics::ReportDiag(const PathDiagnostic& D) {

   // Create the HTML directory if it is missing.

   if (!createdDir) {
     createdDir = true;
     std::string ErrorMsg;
     Directory.createDirectoryOnDisk(true, &ErrorMsg);

     if (!Directory.isDirectory()) {
       llvm::cerr << "warning: could not create directory '"
                  << Directory.toString() << "'\n"
                  << "reason: " << ErrorMsg << '\n';

       noDir = true;

       return;
     }
   }

   if (noDir)
     return;

   SourceManager &SMgr = D.begin()->getLocation().getManager();
   FileID FID;

   // Verify that the entire path is from the same FileID.
   for (PathDiagnostic::const_iterator I = D.begin(), E = D.end(); I != E; ++I) {
     FullSourceLoc L = I->getLocation().getInstantiationLoc();

     if (FID.isInvalid()) {
       FID = SMgr.getFileID(L);
     } else if (SMgr.getFileID(L) != FID)
       return; // FIXME: Emit a warning?

     // Check the source ranges.
     for (PathDiagnosticPiece::range_iterator RI=I->ranges_begin(),
                                              RE=I->ranges_end(); RI!=RE; ++RI) {

       SourceLocation L = SMgr.getInstantiationLoc(RI->getBegin());

       if (!L.isFileID() || SMgr.getFileID(L) != FID)
         return; // FIXME: Emit a warning?

       L = SMgr.getInstantiationLoc(RI->getEnd());

       if (!L.isFileID() || SMgr.getFileID(L) != FID)
         return; // FIXME: Emit a warning?
     }
   }

   if (FID.isInvalid())
     return; // FIXME: Emit a warning?

   // Create a new rewriter to generate HTML.
   Rewriter R(SMgr);

   // Process the path.

   unsigned n = D.size();
   unsigned max = n;

   for (PathDiagnostic::const_reverse_iterator I=D.rbegin(), E=D.rend();
         I!=E; ++I, --n) {

     HandlePiece(R, FID, *I, n, max);
   }

   // Add line numbers, header, footer, etc.

   // unsigned FID = R.getSourceMgr().getMainFileID();
   html::EscapeText(R, FID);
   html::AddLineNumbers(R, FID);

   // If we have a preprocessor, relex the file and syntax highlight.
   // We might not have a preprocessor if we come from a deserialized AST file,
   // for example.

   if (PP) html::SyntaxHighlight(R, FID, *PP);

   // FIXME: We eventually want to use PPF to create a fresh Preprocessor,
   //  once we have worked out the bugs.
   //
   // if (PPF) html::HighlightMacros(R, FID, *PPF);
   //
   if (PP) html::HighlightMacros(R, FID, *PP);

   // Get the full directory name of the analyzed file.

   const FileEntry* Entry = SMgr.getFileEntryForID(FID);

   // This is a cludge; basically we want to append either the full
   // working directory if we have no directory information.  This is
   // a work in progress.

   std::string DirName = "";

   if (!llvm::sys::Path(Entry->getName()).isAbsolute()) {
     llvm::sys::Path P = llvm::sys::Path::GetCurrentDirectory();
     DirName = P.toString() + "/";
   }

   // Add the name of the file as an <h1> tag.

   {
     std::string s;
     llvm::raw_string_ostream os(s);

     os << "<!-- REPORTHEADER -->\n"
        << "<h3>Bug Summary</h3>\n<table class=\"simpletable\">\n"
           "<tr><td class=\"rowname\">File:</td><td>"
        << html::EscapeText(DirName)
        << html::EscapeText(Entry->getName())
        << "</td></tr>\n<tr><td class=\"rowname\">Location:</td><td>"
           "<a href=\"#EndPath\">line "
        << (*D.rbegin()).getLocation().getInstantiationLineNumber()
        << ", column "
        << (*D.rbegin()).getLocation().getInstantiationColumnNumber()
        << "</a></td></tr>\n"
           "<tr><td class=\"rowname\">Description:</td><td>"
        << D.getDescription() << "</td></tr>\n";

     // Output any other meta data.

     for (PathDiagnostic::meta_iterator I=D.meta_begin(), E=D.meta_end();
          I!=E; ++I) {
       os << "<tr><td></td><td>" << html::EscapeText(*I) << "</td></tr>\n";
     }

     os << "</table>\n<!-- REPORTSUMMARYEXTRA -->\n"
           "<h3>Annotated Source Code</h3>\n";

     R.InsertStrBefore(SMgr.getLocForStartOfFile(FID), os.str());
   }

   // Embed meta-data tags.

   const std::string& BugDesc = D.getDescription();

   if (!BugDesc.empty()) {
     std::string s;
     llvm::raw_string_ostream os(s);
     os << "\n<!-- BUGDESC " << BugDesc << " -->\n";
     R.InsertStrBefore(SMgr.getLocForStartOfFile(FID), os.str());
   }

   const std::string& BugType = D.getBugType();
   if (!BugType.empty()) {
     std::string s;
     llvm::raw_string_ostream os(s);
     os << "\n<!-- BUGTYPE " << BugType << " -->\n";
     R.InsertStrBefore(SMgr.getLocForStartOfFile(FID), os.str());
   }

   const std::string& BugCategory = D.getCategory();

   if (!BugCategory.empty()) {
     std::string s;
     llvm::raw_string_ostream os(s);
     os << "\n<!-- BUGCATEGORY " << BugCategory << " -->\n";
     R.InsertStrBefore(SMgr.getLocForStartOfFile(FID), os.str());
   }

   {
     std::string s;
     llvm::raw_string_ostream os(s);
     os << "\n<!-- BUGFILE " << DirName << Entry->getName() << " -->\n";
     R.InsertStrBefore(SMgr.getLocForStartOfFile(FID), os.str());
   }

   {
     std::string s;
     llvm::raw_string_ostream os(s);
     os << "\n<!-- BUGLINE "
        << D.back()->getLocation().getInstantiationLineNumber() << " -->\n";
     R.InsertStrBefore(SMgr.getLocForStartOfFile(FID), os.str());
   }

   {
     std::string s;
     llvm::raw_string_ostream os(s);
     os << "\n<!-- BUGPATHLENGTH " << D.size() << " -->\n";
     R.InsertStrBefore(SMgr.getLocForStartOfFile(FID), os.str());
   }

   // Add CSS, header, and footer.

   html::AddHeaderFooterInternalBuiltinCSS(R, FID, Entry->getName());

   // Get the rewrite buffer.
   const RewriteBuffer *Buf = R.getRewriteBufferFor(FID);

   if (!Buf) {
     llvm::cerr << "warning: no diagnostics generated for main file.\n";
     return;
   }

   // Create the stream to write out the HTML.
   std::ofstream os;

   {
     // Create a path for the target HTML file.
     llvm::sys::Path F(FilePrefix);
     F.makeUnique(false, NULL);

     // Rename the file with an HTML extension.
     llvm::sys::Path H(F);
     H.appendSuffix("html");
     F.renamePathOnDisk(H, NULL);

     os.open(H.toString().c_str());

     if (!os) {
       llvm::cerr << "warning: could not create file '" << F.toString() << "'\n";
       return;
     }
   }

   // Emit the HTML to disk.

   for (RewriteBuffer::iterator I = Buf->begin(), E = Buf->end(); I!=E; ++I)
       os << *I;
 }

 void HTMLDiagnostics::HandlePiece(Rewriter& R, FileID BugFileID,
                                   const PathDiagnosticPiece& P,
                                   unsigned num, unsigned max) {

   // For now, just draw a box above the line in question, and emit the
   // warning.
   FullSourceLoc Pos = P.getLocation();

   if (!Pos.isValid())
     return;

   SourceManager &SM = R.getSourceMgr();
   assert(&Pos.getManager() == &SM && "SourceManagers are different!");
   std::pair<FileID, unsigned> LPosInfo = SM.getDecomposedInstantiationLoc(Pos);

   if (LPosInfo.first != BugFileID)
     return;

   const llvm::MemoryBuffer *Buf = SM.getBuffer(LPosInfo.first);
   const char* FileStart = Buf->getBufferStart();

   // Compute the column number.  Rewind from the current position to the start
   // of the line.
   unsigned ColNo = SM.getColumnNumber(LPosInfo.first, LPosInfo.second);
   const char *TokInstantiationPtr =Pos.getInstantiationLoc().getCharacterData();
   const char *LineStart = TokInstantiationPtr-ColNo;

   // Only compute LineEnd if we display below a line.
   const char *LineEnd = TokInstantiationPtr;

   if (P.getDisplayHint() == PathDiagnosticPiece::Below) {
     const char* FileEnd = Buf->getBufferEnd();

     while (*LineEnd != '\n' && LineEnd != FileEnd)
       ++LineEnd;
   }

   // Compute the margin offset by counting tabs and non-tabs.

   unsigned PosNo = 0;

   for (const char* c = LineStart; c != TokInstantiationPtr; ++c)
     PosNo += *c == '\t' ? 8 : 1;

   // Create the html for the message.
   {
     // Get the string and determining its maximum substring.
     const std::string& Msg = P.getString();
     unsigned max_token = 0;
     unsigned cnt = 0;
     unsigned len = Msg.size();

     for (std::string::const_iterator I=Msg.begin(), E=Msg.end(); I!=E; ++I)
       switch (*I) {
         default:
           ++cnt;
           continue;
         case ' ':
         case '\t':
         case '\n':
           if (cnt > max_token) max_token = cnt;
           cnt = 0;
       }

     if (cnt > max_token) max_token = cnt;

     // Next, determine the approximate size of the message bubble in em.
     unsigned em;
     const unsigned max_line = 120;

     if (max_token >= max_line)
       em = max_token / 2;
     else {
       unsigned characters = max_line;
       unsigned lines = len / max_line;

       if (lines > 0) {
         for (; characters > max_token; --characters)
           if (len / characters > lines) {
             ++characters;
             break;
           }
       }

       em = characters / 2;
     }

     // Now generate the message bubble.
     std::string s;
     llvm::raw_string_ostream os(s);

     os << "\n<tr><td class=\"num\"></td><td class=\"line\"><div id=\"";

     if (num == max)
       os << "EndPath";
     else
       os << "Path" << num;

     os << "\" class=\"msg\" style=\"margin-left:" << PosNo << "ex";
     if (em < max_line/2) os << "; max-width:" << em << "em";
     os << "\">";

     if (max > 1)
       os << "<span class=\"PathIndex\">[" << num << "]</span> ";

     os << html::EscapeText(Msg) << "</div></td></tr>";

     // Insert the new html.
     unsigned DisplayPos;
     switch (P.getDisplayHint()) {
     default: assert(0 && "Unhandled hint.");
     case PathDiagnosticPiece::Above:
       DisplayPos = LineStart - FileStart;
       break;
     case PathDiagnosticPiece::Below:
       DisplayPos = LineEnd - FileStart;
       break;
     }

     SourceLocation Loc =
       SM.getLocForStartOfFile(LPosInfo.first).getFileLocWithOffset(DisplayPos);
     R.InsertStrBefore(Loc, os.str());
   }

   // Now highlight the ranges.

   for (const SourceRange *I = P.ranges_begin(), *E = P.ranges_end();
         I != E; ++I)
     HighlightRange(R, LPosInfo.first, *I);
 }

 void HTMLDiagnostics::HighlightRange(Rewriter& R, FileID BugFileID,
                                      SourceRange Range) {

   SourceManager& SM = R.getSourceMgr();

   SourceLocation InstantiationStart = SM.getInstantiationLoc(Range.getBegin());
   unsigned StartLineNo = SM.getInstantiationLineNumber(InstantiationStart);

   SourceLocation InstantiationEnd = SM.getInstantiationLoc(Range.getEnd());
   unsigned EndLineNo = SM.getInstantiationLineNumber(InstantiationEnd);

   if (EndLineNo < StartLineNo)
     return;

   if (SM.getFileID(InstantiationStart) != BugFileID ||
       SM.getFileID(InstantiationEnd) != BugFileID)
     return;

   // Compute the column number of the end.
   unsigned EndColNo = SM.getInstantiationColumnNumber(InstantiationEnd);
   unsigned OldEndColNo = EndColNo;

   if (EndColNo) {
     // Add in the length of the token, so that we cover multi-char tokens.
     EndColNo += Lexer::MeasureTokenLength(Range.getEnd(), SM) - 1;
   }

   // Highlight the range.  Make the span tag the outermost tag for the
   // selected range.

   SourceLocation E =
     InstantiationEnd.getFileLocWithOffset(EndColNo - OldEndColNo);

   html::HighlightRange(R, InstantiationStart, E,
                        "<span class=\"mrange\">", "</span>");
 }
	//===--- HTMLDiagnostics.cpp - HTML Diagnostics for Paths ----- C++ --===//
	//
	// 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 HTMLDiagnostics object.
	//
	//===----------------------------------------------------------------------===//

	#include "clang/Driver/PathDiagnosticClients.h"
	#include "clang/Analysis/PathDiagnostic.h"
	#include "clang/AST/ASTContext.h"
	#include "clang/AST/Decl.h"
	#include "clang/Basic/SourceManager.h"
	#include "clang/Basic/FileManager.h"
	#include "clang/Rewrite/Rewriter.h"
	#include "clang/Rewrite/HTMLRewrite.h"
	#include "clang/Lex/Lexer.h"
	#include "llvm/Support/Compiler.h"
	#include "llvm/Support/MemoryBuffer.h"
	#include "llvm/Support/Streams.h"
	#include "llvm/Support/raw_ostream.h"
	#include "llvm/System/Path.h"
	#include <fstream>
	using namespace clang;

	//===----------------------------------------------------------------------===//
	// Boilerplate.
	//===----------------------------------------------------------------------===//

	namespace {

	class VISIBILITY_HIDDEN HTMLDiagnostics : public PathDiagnosticClient {
	llvm::sys::Path Directory, FilePrefix;
	bool createdDir, noDir;
	Preprocessor* PP;
	PreprocessorFactory* PPF;
	std::vector<const PathDiagnostic*> BatchedDiags;
	public:
	HTMLDiagnostics(const std::string& prefix, Preprocessor* pp,
	PreprocessorFactory* ppf);

	virtual ~HTMLDiagnostics();

	virtual void HandlePathDiagnostic(const PathDiagnostic* D);

	void HandlePiece(Rewriter& R, FileID BugFileID,
	const PathDiagnosticPiece& P, unsigned num, unsigned max);

	void HighlightRange(Rewriter& R, FileID BugFileID, SourceRange Range);

	void ReportDiag(const PathDiagnostic& D);
	};

	} // end anonymous namespace

	HTMLDiagnostics::HTMLDiagnostics(const std::string& prefix, Preprocessor* pp,
	PreprocessorFactory* ppf)
	: Directory(prefix), FilePrefix(prefix), createdDir(false), noDir(false),
	PP(pp), PPF(ppf) {

	// All html files begin with "report"
	FilePrefix.appendComponent("report");
	}

	PathDiagnosticClient*
	clang::CreateHTMLDiagnosticClient(const std::string& prefix, Preprocessor* PP,
	PreprocessorFactory* PPF) {

	return new HTMLDiagnostics(prefix, PP, PPF);
	}

	//===----------------------------------------------------------------------===//
	// Report processing.
	//===----------------------------------------------------------------------===//

	void HTMLDiagnostics::HandlePathDiagnostic(const PathDiagnostic* D) {
	if (!D)
	return;

	if (D->empty()) {
	delete D;
	return;
	}

	BatchedDiags.push_back(D);
	}

	HTMLDiagnostics::~HTMLDiagnostics() {

	while (!BatchedDiags.empty()) {
	const PathDiagnostic* D = BatchedDiags.back();
	BatchedDiags.pop_back();
	ReportDiag(*D);
	delete D;
	}
	}

	void HTMLDiagnostics::ReportDiag(const PathDiagnostic& D) {

	// Create the HTML directory if it is missing.

	if (!createdDir) {
	createdDir = true;
	std::string ErrorMsg;
	Directory.createDirectoryOnDisk(true, &ErrorMsg);

	if (!Directory.isDirectory()) {
	llvm::cerr << "warning: could not create directory '"
	<< Directory.toString() << "'\n"
	<< "reason: " << ErrorMsg << '\n';

	noDir = true;

	return;
	}
	}

	if (noDir)
	return;

	SourceManager &SMgr = D.begin()->getLocation().getManager();
	FileID FID;

	// Verify that the entire path is from the same FileID.
	for (PathDiagnostic::const_iterator I = D.begin(), E = D.end(); I != E; ++I) {
	FullSourceLoc L = I->getLocation().getInstantiationLoc();

	if (FID.isInvalid()) {
	FID = SMgr.getFileID(L);
	} else if (SMgr.getFileID(L) != FID)
	return; // FIXME: Emit a warning?

	// Check the source ranges.
	for (PathDiagnosticPiece::range_iterator RI=I->ranges_begin(),
	RE=I->ranges_end(); RI!=RE; ++RI) {

	SourceLocation L = SMgr.getInstantiationLoc(RI->getBegin());

	if (!L.isFileID() \|\| SMgr.getFileID(L) != FID)
	return; // FIXME: Emit a warning?

	L = SMgr.getInstantiationLoc(RI->getEnd());

	if (!L.isFileID() \|\| SMgr.getFileID(L) != FID)
	return; // FIXME: Emit a warning?
	}
	}

	if (FID.isInvalid())
	return; // FIXME: Emit a warning?

	// Create a new rewriter to generate HTML.
	Rewriter R(SMgr);

	// Process the path.

	unsigned n = D.size();
	unsigned max = n;

	for (PathDiagnostic::const_reverse_iterator I=D.rbegin(), E=D.rend();
	I!=E; ++I, --n) {

	HandlePiece(R, FID, *I, n, max);
	}

	// Add line numbers, header, footer, etc.

	// unsigned FID = R.getSourceMgr().getMainFileID();
	html::EscapeText(R, FID);
	html::AddLineNumbers(R, FID);

	// If we have a preprocessor, relex the file and syntax highlight.
	// We might not have a preprocessor if we come from a deserialized AST file,
	// for example.

	if (PP) html::SyntaxHighlight(R, FID, *PP);

	// FIXME: We eventually want to use PPF to create a fresh Preprocessor,
	// once we have worked out the bugs.
	//
	// if (PPF) html::HighlightMacros(R, FID, *PPF);
	//
	if (PP) html::HighlightMacros(R, FID, *PP);

	// Get the full directory name of the analyzed file.

	const FileEntry* Entry = SMgr.getFileEntryForID(FID);

	// This is a cludge; basically we want to append either the full
	// working directory if we have no directory information. This is
	// a work in progress.

	std::string DirName = "";

	if (!llvm::sys::Path(Entry->getName()).isAbsolute()) {
	llvm::sys::Path P = llvm::sys::Path::GetCurrentDirectory();
	DirName = P.toString() + "/";
	}

	// Add the name of the file as an <h1> tag.

	{
	std::string s;
	llvm::raw_string_ostream os(s);

	os << "<!-- REPORTHEADER -->\n"
	<< "<h3>Bug Summary</h3>\n<table class=\"simpletable\">\n"
	"<tr><td class=\"rowname\">File:</td><td>"
	<< html::EscapeText(DirName)
	<< html::EscapeText(Entry->getName())
	<< "</td></tr>\n<tr><td class=\"rowname\">Location:</td><td>"
	"<a href=\"#EndPath\">line "
	<< (*D.rbegin()).getLocation().getInstantiationLineNumber()
	<< ", column "
	<< (*D.rbegin()).getLocation().getInstantiationColumnNumber()
	<< "</a></td></tr>\n"
	"<tr><td class=\"rowname\">Description:</td><td>"
	<< D.getDescription() << "</td></tr>\n";

	// Output any other meta data.

	for (PathDiagnostic::meta_iterator I=D.meta_begin(), E=D.meta_end();
	I!=E; ++I) {
	os << "<tr><td></td><td>" << html::EscapeText(*I) << "</td></tr>\n";
	}

	os << "</table>\n<!-- REPORTSUMMARYEXTRA -->\n"
	"<h3>Annotated Source Code</h3>\n";

	R.InsertStrBefore(SMgr.getLocForStartOfFile(FID), os.str());
	}

	// Embed meta-data tags.

	const std::string& BugDesc = D.getDescription();

	if (!BugDesc.empty()) {
	std::string s;
	llvm::raw_string_ostream os(s);
	os << "\n<!-- BUGDESC " << BugDesc << " -->\n";
	R.InsertStrBefore(SMgr.getLocForStartOfFile(FID), os.str());
	}

	const std::string& BugType = D.getBugType();
	if (!BugType.empty()) {
	std::string s;
	llvm::raw_string_ostream os(s);
	os << "\n<!-- BUGTYPE " << BugType << " -->\n";
	R.InsertStrBefore(SMgr.getLocForStartOfFile(FID), os.str());
	}

	const std::string& BugCategory = D.getCategory();

	if (!BugCategory.empty()) {
	std::string s;
	llvm::raw_string_ostream os(s);
	os << "\n<!-- BUGCATEGORY " << BugCategory << " -->\n";
	R.InsertStrBefore(SMgr.getLocForStartOfFile(FID), os.str());
	}

	{
	std::string s;
	llvm::raw_string_ostream os(s);
	os << "\n<!-- BUGFILE " << DirName << Entry->getName() << " -->\n";
	R.InsertStrBefore(SMgr.getLocForStartOfFile(FID), os.str());
	}

	{
	std::string s;
	llvm::raw_string_ostream os(s);
	os << "\n<!-- BUGLINE "
	<< D.back()->getLocation().getInstantiationLineNumber() << " -->\n";
	R.InsertStrBefore(SMgr.getLocForStartOfFile(FID), os.str());
	}

	{
	std::string s;
	llvm::raw_string_ostream os(s);
	os << "\n<!-- BUGPATHLENGTH " << D.size() << " -->\n";
	R.InsertStrBefore(SMgr.getLocForStartOfFile(FID), os.str());
	}

	// Add CSS, header, and footer.

	html::AddHeaderFooterInternalBuiltinCSS(R, FID, Entry->getName());

	// Get the rewrite buffer.
	const RewriteBuffer *Buf = R.getRewriteBufferFor(FID);

	if (!Buf) {
	llvm::cerr << "warning: no diagnostics generated for main file.\n";
	return;
	}

	// Create the stream to write out the HTML.
	std::ofstream os;

	{
	// Create a path for the target HTML file.
	llvm::sys::Path F(FilePrefix);
	F.makeUnique(false, NULL);

	// Rename the file with an HTML extension.
	llvm::sys::Path H(F);
	H.appendSuffix("html");
	F.renamePathOnDisk(H, NULL);

	os.open(H.toString().c_str());

	if (!os) {
	llvm::cerr << "warning: could not create file '" << F.toString() << "'\n";
	return;
	}
	}

	// Emit the HTML to disk.

	for (RewriteBuffer::iterator I = Buf->begin(), E = Buf->end(); I!=E; ++I)
	os << *I;
	}

	void HTMLDiagnostics::HandlePiece(Rewriter& R, FileID BugFileID,
	const PathDiagnosticPiece& P,
	unsigned num, unsigned max) {

	// For now, just draw a box above the line in question, and emit the
	// warning.
	FullSourceLoc Pos = P.getLocation();

	if (!Pos.isValid())
	return;

	SourceManager &SM = R.getSourceMgr();
	assert(&Pos.getManager() == &SM && "SourceManagers are different!");
	std::pair<FileID, unsigned> LPosInfo = SM.getDecomposedInstantiationLoc(Pos);

	if (LPosInfo.first != BugFileID)
	return;

	const llvm::MemoryBuffer *Buf = SM.getBuffer(LPosInfo.first);
	const char* FileStart = Buf->getBufferStart();

	// Compute the column number. Rewind from the current position to the start
	// of the line.
	unsigned ColNo = SM.getColumnNumber(LPosInfo.first, LPosInfo.second);
	const char *TokInstantiationPtr =Pos.getInstantiationLoc().getCharacterData();
	const char *LineStart = TokInstantiationPtr-ColNo;

	// Only compute LineEnd if we display below a line.
	const char *LineEnd = TokInstantiationPtr;

	if (P.getDisplayHint() == PathDiagnosticPiece::Below) {
	const char* FileEnd = Buf->getBufferEnd();

	while (*LineEnd != '\n' && LineEnd != FileEnd)
	++LineEnd;
	}

	// Compute the margin offset by counting tabs and non-tabs.

	unsigned PosNo = 0;

	for (const char* c = LineStart; c != TokInstantiationPtr; ++c)
	PosNo += *c == '\t' ? 8 : 1;

	// Create the html for the message.
	{
	// Get the string and determining its maximum substring.
	const std::string& Msg = P.getString();
	unsigned max_token = 0;
	unsigned cnt = 0;
	unsigned len = Msg.size();

	for (std::string::const_iterator I=Msg.begin(), E=Msg.end(); I!=E; ++I)
	switch (*I) {
	default:
	++cnt;
	continue;
	case ' ':
	case '\t':
	case '\n':
	if (cnt > max_token) max_token = cnt;
	cnt = 0;
	}

	if (cnt > max_token) max_token = cnt;

	// Next, determine the approximate size of the message bubble in em.
	unsigned em;
	const unsigned max_line = 120;

	if (max_token >= max_line)
	em = max_token / 2;
	else {
	unsigned characters = max_line;
	unsigned lines = len / max_line;

	if (lines > 0) {
	for (; characters > max_token; --characters)
	if (len / characters > lines) {
	++characters;
	break;
	}
	}

	em = characters / 2;
	}

	// Now generate the message bubble.
	std::string s;
	llvm::raw_string_ostream os(s);

	os << "\n<tr><td class=\"num\"></td><td class=\"line\"><div id=\"";

	if (num == max)
	os << "EndPath";
	else
	os << "Path" << num;

	os << "\" class=\"msg\" style=\"margin-left:" << PosNo << "ex";
	if (em < max_line/2) os << "; max-width:" << em << "em";
	os << "\">";

	if (max > 1)
	os << "<span class=\"PathIndex\">[" << num << "]</span> ";

	os << html::EscapeText(Msg) << "</div></td></tr>";

	// Insert the new html.
	unsigned DisplayPos;
	switch (P.getDisplayHint()) {
	default: assert(0 && "Unhandled hint.");
	case PathDiagnosticPiece::Above:
	DisplayPos = LineStart - FileStart;
	break;
	case PathDiagnosticPiece::Below:
	DisplayPos = LineEnd - FileStart;
	break;
	}

	SourceLocation Loc =
	SM.getLocForStartOfFile(LPosInfo.first).getFileLocWithOffset(DisplayPos);
	R.InsertStrBefore(Loc, os.str());
	}

	// Now highlight the ranges.

	for (const SourceRange I = P.ranges_begin(), E = P.ranges_end();
	I != E; ++I)
	HighlightRange(R, LPosInfo.first, *I);
	}

	void HTMLDiagnostics::HighlightRange(Rewriter& R, FileID BugFileID,
	SourceRange Range) {

	SourceManager& SM = R.getSourceMgr();

	SourceLocation InstantiationStart = SM.getInstantiationLoc(Range.getBegin());
	unsigned StartLineNo = SM.getInstantiationLineNumber(InstantiationStart);

	SourceLocation InstantiationEnd = SM.getInstantiationLoc(Range.getEnd());
	unsigned EndLineNo = SM.getInstantiationLineNumber(InstantiationEnd);

	if (EndLineNo < StartLineNo)
	return;

	if (SM.getFileID(InstantiationStart) != BugFileID \|\|
	SM.getFileID(InstantiationEnd) != BugFileID)
	return;

	// Compute the column number of the end.
	unsigned EndColNo = SM.getInstantiationColumnNumber(InstantiationEnd);
	unsigned OldEndColNo = EndColNo;

	if (EndColNo) {
	// Add in the length of the token, so that we cover multi-char tokens.
	EndColNo += Lexer::MeasureTokenLength(Range.getEnd(), SM) - 1;
	}

	// Highlight the range. Make the span tag the outermost tag for the
	// selected range.

	SourceLocation E =
	InstantiationEnd.getFileLocWithOffset(EndColNo - OldEndColNo);

	html::HighlightRange(R, InstantiationStart, E,
	"<span class=\"mrange\">", "</span>");
	}