regex_compile.hpp

来自「CGAL is a collaborative effort of severa」· HPP 代码 · 共 1,861 行 · 第 1/5 页

            }
            break;
         case traits_type::syntax_or:
            if(((_flags & bk_vbar) == 0) || (_flags & limited_ops))
               break;
            goto alt_string_jump;
         case traits_type::syntax_open_brace:
            if( ((_flags & bk_braces) == 0) || ((_flags & intervals) == 0))
               break;

            // we have {x} or {x,} or {x,y}:
            parse_range(ptr, end, rep_min, rep_max);
            goto repeat_jump;

         case traits_type::syntax_digit:
            if(_flags & bk_refs)
            {
               // update previous:
               int i = traits_inst.toi((charT)c);
               if(i == 0)
               {
                  // we can have \025 which means take char whose
                  // code is 25 (octal), so parse string:
                  c = traits_inst.toi(ptr, end, -8);
                  --ptr;
                  break;
               }
               dat = add_simple(dat, re_detail::syntax_element_backref, sizeof(re_detail::re_brace));
               static_cast<re_detail::re_brace*>(dat)->index = i;
               ++ptr;
               continue;
            }
            break;
         case traits_type::syntax_b:     // re_detail::syntax_element_word_boundary
            dat = add_simple(dat, re_detail::syntax_element_word_boundary);
            ++ptr;
            continue;
         case traits_type::syntax_B:
            dat = add_simple(dat, re_detail::syntax_element_within_word);
            ++ptr;
            continue;
         case traits_type::syntax_left_word:
            dat = add_simple(dat, re_detail::syntax_element_word_start);
            ++ptr;
            continue;
         case traits_type::syntax_right_word:
            dat = add_simple(dat, re_detail::syntax_element_word_end);
            ++ptr;
            continue;
         case traits_type::syntax_w:     //re_detail::syntax_element_word_char
            dat = compile_set_simple(dat, traits_type::char_class_word);
            ++ptr;
            continue;
         case traits_type::syntax_W:
            dat = compile_set_simple(dat, traits_type::char_class_word, true);
            ++ptr;
            continue;
         case traits_type::syntax_d:     //re_detail::syntax_element_word_char
            dat = compile_set_simple(dat, traits_type::char_class_digit);
            ++ptr;
            continue;
         case traits_type::syntax_D:
            dat = compile_set_simple(dat, traits_type::char_class_digit, true);
            ++ptr;
            continue;
         case traits_type::syntax_s:     //re_detail::syntax_element_word_char
            dat = compile_set_simple(dat, traits_type::char_class_space);
            ++ptr;
            continue;
         case traits_type::syntax_S:
            dat = compile_set_simple(dat, traits_type::char_class_space, true);
            ++ptr;
            continue;
         case traits_type::syntax_l:     //re_detail::syntax_element_word_char
            dat = compile_set_simple(dat, traits_type::char_class_lower);
            ++ptr;
            continue;
         case traits_type::syntax_L:
            dat = compile_set_simple(dat, traits_type::char_class_lower, true);
            ++ptr;
            continue;
         case traits_type::syntax_u:     //re_detail::syntax_element_word_char
            dat = compile_set_simple(dat, traits_type::char_class_upper);
            ++ptr;
            continue;
         case traits_type::syntax_U:
            dat = compile_set_simple(dat, traits_type::char_class_upper, true);
            ++ptr;
            continue;
         case traits_type::syntax_Q:
            ++ptr;
            while(true)
            {
               if(ptr == end)
               {
                  fail(REG_EESCAPE);
                  return error_code();
               }
               if(traits_inst.syntax_type((traits_size_type)(traits_uchar_type)*ptr) == traits_type::syntax_slash)
               {
                  ++ptr;
                  if((ptr != end) && (traits_inst.syntax_type((traits_size_type)(traits_uchar_type)*ptr) == traits_type::syntax_E))
                     break;
                  else
                  {
                     dat = add_literal(dat, *(ptr-1));
                     continue;
                  }
               }
               dat = add_literal(dat, *ptr);
               ++ptr;
            }
            ++ptr;
            continue;
         case traits_type::syntax_C:
            dat = add_simple(dat, re_detail::syntax_element_wild);
            ++ptr;
            continue;
         case traits_type::syntax_X:
            dat = add_simple(dat, re_detail::syntax_element_combining);
            ++ptr;
            continue;
         case traits_type::syntax_Z:
            dat = add_simple(dat, re_detail::syntax_element_soft_buffer_end);
            ++ptr;
            continue;
         case traits_type::syntax_G:
            dat = add_simple(dat, re_detail::syntax_element_restart_continue);
            ++ptr;
            continue;
         case traits_type::syntax_start_buffer:
            dat = add_simple(dat, re_detail::syntax_element_buffer_start);
            ++ptr;
            continue;
         case traits_type::syntax_end_buffer:
            dat = add_simple(dat, re_detail::syntax_element_buffer_end);
            ++ptr;
            continue;
         default:
            c = (traits_size_type)(traits_uchar_type)parse_escape(ptr, end);
            dat = add_literal(dat, (charT)c);
            continue;
         }
         dat = add_literal(dat, (charT)c);
         ++ptr;
         break;
      }
      case traits_type::syntax_dollar:
         dat = add_simple(dat, re_detail::syntax_element_end_line, sizeof(re_detail::re_syntax_base));
         ++ptr;
         continue;
      case traits_type::syntax_caret:
         dat = add_simple(dat, re_detail::syntax_element_start_line, sizeof(re_detail::re_syntax_base));
         ++ptr;
         continue;
      case traits_type::syntax_dot:
         dat = add_simple(dat, re_detail::syntax_element_wild, sizeof(re_detail::re_syntax_base));
         ++ptr;
         continue;
      case traits_type::syntax_star:
         rep_min = 0;
         rep_max = (unsigned)-1;

         repeat_jump:
         {
          std::ptrdiff_t offset;
            if(dat == 0)
            {
               fail(REG_BADRPT);
               return error_code();
            }
            switch(dat->type)
            {
            case re_detail::syntax_element_endmark:
               offset = last_mark_popped;
               break;
            case re_detail::syntax_element_literal:
               if(static_cast<re_detail::re_literal*>(dat)->length > 1)
               {
                  // update previous:
                  charT lit = *reinterpret_cast<charT*>(reinterpret_cast<char*>(dat) + sizeof(re_detail::re_literal) + ((static_cast<re_detail::re_literal*>(dat)->length-1)*sizeof(charT)));
                  --static_cast<re_detail::re_literal*>(dat)->length;
                  dat = add_simple(dat, re_detail::syntax_element_literal, sizeof(re_detail::re_literal) + sizeof(charT));
                  static_cast<re_detail::re_literal*>(dat)->length = 1;
                  *reinterpret_cast<charT*>(static_cast<re_detail::re_literal*>(dat)+1) = lit;
               }
               offset = reinterpret_cast<char*>(dat) - reinterpret_cast<char*>(data.data());
               break;
            case re_detail::syntax_element_backref:
            case re_detail::syntax_element_long_set:
            case re_detail::syntax_element_set:
            case re_detail::syntax_element_wild:
            case re_detail::syntax_element_combining:
               // we're repeating a single item:
               offset = reinterpret_cast<char*>(dat) - reinterpret_cast<char*>(data.data());
               break;
            default:
               fail(REG_BADRPT);
               return error_code();
            }
            data.align();
            dat->next.i = data.size();
            //unsigned pos = (char*)dat - (char*)data.data();

            // add the trailing jump:
            dat = add_simple(dat, re_detail::syntax_element_jump, re_detail::re_jump_size);
            static_cast<re_detail::re_jump*>(dat)->alt.i = 0;

            // now insert the leading repeater:
            dat = static_cast<re_detail::re_syntax_base*>(data.insert(offset, re_detail::re_repeater_size));
            dat->next.i = (reinterpret_cast<char*>(dat) - reinterpret_cast<char*>(data.data())) + re_detail::re_repeater_size;
            dat->type = re_detail::syntax_element_rep;
            static_cast<re_detail::re_repeat*>(dat)->alt.i = data.size();
            static_cast<re_detail::re_repeat*>(dat)->min = rep_min;
            static_cast<re_detail::re_repeat*>(dat)->max = rep_max;
            static_cast<re_detail::re_repeat*>(dat)->leading = false;
            static_cast<re_detail::re_repeat*>(dat)->greedy = true;
            move_offsets(dat, re_detail::re_repeater_size);
            ++ptr;
            //
            // now check to see if we have a non-greedy repeat:
            if((ptr != end) && (_flags & (limited_ops | bk_plus_qm | bk_braces)) == 0)
            {
               c = (traits_size_type)(traits_uchar_type)*ptr;
               if(traits_type::syntax_question == traits_inst.syntax_type(c))
               {
                  // OK repeat is non-greedy:
                  static_cast<re_detail::re_repeat*>(dat)->greedy = false;
                  ++ptr;
               }
            }
            dat = reinterpret_cast<re_detail::re_syntax_base*>(reinterpret_cast<char*>(data.data()) + data.size() - re_detail::re_jump_size);
            static_cast<re_detail::re_repeat*>(dat)->alt.i = offset;
            continue;
         }
      case traits_type::syntax_plus:
         if(_flags & (bk_plus_qm | limited_ops))
         {
            dat = add_literal(dat, (charT)c);
            ++ptr;
            continue;
         }
         rep_min = 1;
         rep_max = (unsigned)-1;
         goto repeat_jump;
      case traits_type::syntax_question:
         if(_flags & (bk_plus_qm | limited_ops))
         {
            dat = add_literal(dat, (charT)c);
            ++ptr;
            continue;
         }
         rep_min = 0;
         rep_max = 1;
         goto repeat_jump;
      case traits_type::syntax_open_set:
         // update previous:
         if(dat)
         {
            data.align();
            dat->next.i = data.size();
         }
         // extend:
         dat = compile_set(ptr, end);
         if(dat == 0)
         {
            if((_flags & regbase::failbit) == 0)
               fail(REG_EBRACK);
            return error_code();
         }
         break;
      case traits_type::syntax_or:
      {
         if(_flags & (bk_vbar | limited_ops))
         {
            dat = add_literal(dat, (charT)c);
            ++ptr;
            continue;
         }

         alt_string_jump:

         // update previous:
         if(dat == 0)
         {
            // start of pattern can't have empty "|"
            fail(REG_EMPTY);
            return error_code();
         }
         // see if we have an empty alternative:
         if(mark.empty() == false)
            if(mark.peek() == data.index(dat))
            {
               fail(REG_EMPTY);
               return error_code();
            }
         // extend:
         dat = add_simple(dat, re_detail::syntax_element_jump, re_detail::re_jump_size);
         data.align();
         //
         // we don't know what value to put here yet,
         // use an arbitrarily large value for now
         // and check it later (TODO!)
         static_cast<re_detail::re_jump*>(dat)->alt.i = INT_MAX/2;

         // now work out where to insert:
         std::size_t offset = 0;
         if(mark.empty() == false)
         {
            // we have a '(' or '|' to go back to:
            offset = mark.peek();
            re_detail::re_syntax_base* base = reinterpret_cast<re_detail::re_syntax_base*>(reinterpret_cast<unsigned char*>(data.data()) + offset);
            offset = base->next.i;
         }
         re_detail::re_jump* j = static_cast<re_detail::re_jump*>(data.insert(offset, re_detail::re_jump_size));
         j->type = re_detail::syntax_element_alt;
         j->next.i = offset + re_detail::re_jump_size;
         j->alt.i = data.size();
         move_offsets(j, re_detail::re_jump_size);
         dat = reinterpret_cast<re_detail::re_syntax_base*>(reinterpret_cast<unsigned char*>(data.data()) + data.size() - re_detail::re_jump_size);
         mark.push(data.size() - re_detail::re_jump_size);
         ++ptr;
         break;
      }
      case traits_type::syntax_open_brace:
         if((_flags & bk_braces) || ((_flags & intervals) == 0))
         {
            dat = add_literal(dat, (charT)c);
            ++ptr;
            continue;
         }
         // we have {x} or {x,} or {x,y}:
         parse_range(ptr, end, rep_min, rep_max);
         goto repeat_jump;
      case traits_type::syntax_newline:
         if(_flags & newline_alt)
            goto alt_string_jump;
         dat = add_literal(dat, (charT)c);
         ++ptr;
         continue;
      case traits_type::syntax_close_brace:
         if(_flags & bk_braces)
         {
            dat = add_literal(dat, (charT)c);
            ++ptr;
            continue;
         }
         fail(REG_BADPAT);
         return error_code();
      default:
         dat = add_literal(dat, (charT)c);
         ++ptr;
         break;
      }  // switch
   }     // while

   //
   // update previous:
   if(dat)
   {
      data.align();
      dat->next.i = data.size();
   }

   // see if we have an empty alternative:
   if(mark.empty() == false)
      if(mark.peek() == data.index(dat) )
      {
         re_detail::re_syntax_base* para = reinterpret_cast<re_detail::re_syntax_base*>(reinterpret_cas