static void html_blockquote(struct Blob *ob, struct Blob *text, void *opaque){
  INTER_BLOCK(ob);
  BLOB_APPEND_LITERAL(ob, "<blockquote>\n");
  BLOB_APPEND_BLOB(ob, text);
  BLOB_APPEND_LITERAL(ob, "</blockquote>\n");
}

/*
** For each byte of pIn which is an ASCII alphanumeric, its lowercase
** form is appended to pOut. The intent is to generate an automated
** HTML ID attribute from, e.g., header text, in particular an ID
** which a human could easily recreate "in their head" while writing a
** document, to facilitate the create of intra-document links.
*/
static void html_text_to_id(Blob const * pIn, Blob *pOut){
  int i;
  unsigned char const * z = (unsigned char const *)pIn->aData;
  for( i = 0; i < pIn->nUsed; ++i, ++z ){
    if(*z<128 && fossil_isalnum(*z)){
      char const Z = (char)fossil_tolower(*z);
      blob_append(pOut, &Z, 1);
    }
  }
}

static void html_header(
  struct Blob *ob,
  struct Blob *text,
  int level,
  void *opaque
){
  struct Blob *title = opaque;
  Blob bId = empty_blob;
  /* The first header at the beginning of a text is considered as
   * a title and not output. */
  if( blob_size(ob)<=PROLOG_SIZE && title!=0 && blob_size(title)==0 ){
    BLOB_APPEND_BLOB(title, text);
    return;
  }
  html_text_to_id(text, &bId);
  INTER_BLOCK(ob);
  if(bId.nUsed>0){
    blob_appendf(ob, "<h%d id=\"%b\">", level, &bId);
  }else{
  blob_appendf(ob, "<h%d>", level);
    blob_appendf(ob, "<h%d>", level);
  }
  BLOB_APPEND_BLOB(ob, text);
  blob_appendf(ob, "</h%d>", level);
  blob_reset(&bId);
}

static void html_hrule(struct Blob *ob, void *opaque){
  INTER_BLOCK(ob);
  BLOB_APPEND_LITERAL(ob, "<hr />\n");
}