Added the beginning of a set of rewriter functions for pretty-printing source
code as HTML.  Added a new driver option "--emit-html" to dump the source
of the main input file as HTML.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@48505 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Rewrite/HTMLRewrite.cpp b/lib/Rewrite/HTMLRewrite.cpp
new file mode 100644
index 0000000..3beede8
--- /dev/null
+++ b/lib/Rewrite/HTMLRewrite.cpp
@@ -0,0 +1,77 @@
+//== HTMLRewrite.cpp - Translate source code into prettified HTML --*- 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 HTMLRewriter clas, which is used to translate the
+//  text of a source file into prettified HTML.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Rewrite/Rewriter.h"
+#include "clang/Rewrite/HTMLRewrite.h"
+#include "clang/Basic/SourceManager.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include <sstream>
+
+using namespace clang;
+
+void html::EscapeText(Rewriter& R, unsigned FileID, bool EscapeSpaces) {
+  
+  const llvm::MemoryBuffer *Buf = R.getSourceMgr().getBuffer(FileID);
+  const char* C = Buf->getBufferStart();
+  const char* FileEnd = Buf->getBufferEnd();
+  
+  assert (C <= FileEnd);
+  
+  for (unsigned FilePos = 0; C != FileEnd ; ++C, ++FilePos) {
+    
+    SourceLocation Loc = SourceLocation::getFileLoc(FileID, FilePos);
+  
+    switch (*C) {
+      default: break;
+        
+      case ' ':
+        if (EscapeSpaces) R.ReplaceText(Loc, 1, "&#32;", 5);
+        break;
+
+      case '<': R.ReplaceText(Loc, 1, "&lt;", 4); break;
+      case '>': R.ReplaceText(Loc, 1, "&gt;", 4); break;
+      case '&': R.ReplaceText(Loc, 1, "&amp;", 5); break;
+    }
+  }
+}
+
+void html::InsertTag(Rewriter& R, html::Tags tag,
+                     SourceLocation B, SourceLocation E,
+                     bool NewlineOpen, bool NewlineClose) {
+  
+  const char* TagStr = 0;
+  
+  switch (tag) {
+    default: break;      
+    case PRE: TagStr = "pre"; break;
+    case HEAD: TagStr = "head"; break;
+    case BODY: TagStr = "body"; break;
+  }
+  
+  assert (TagStr && "Tag not supported.");
+
+  { // Generate the opening tag.
+    std::ostringstream os;  
+    os << '<' << TagStr << '>';
+    if (NewlineOpen) os << '\n';
+    R.InsertTextAfter(B, os.str().c_str(), os.str().size());
+  }
+  
+  { // Generate the closing tag.
+    std::ostringstream os;  
+    os << "</" << TagStr << '>';
+    if (NewlineClose) os << '\n';
+    R.InsertTextBefore(E, os.str().c_str(), os.str().size());
+  }
+}