The C and C++ Include Header Files

/usr/include/c++/11/bits/regex_automaton.tcc


$ cat -n /usr/include/c++/11/bits/regex_automaton.tcc

     1	// class template regex -*- C++ -*-
     2	
     3	// Copyright (C) 2013-2021 Free Software Foundation, Inc.
     4	//
     5	// This file is part of the GNU ISO C++ Library.  This library is free
     6	// software; you can redistribute it and/or modify it under the
     7	// terms of the GNU General Public License as published by the
     8	// Free Software Foundation; either version 3, or (at your option)
     9	// any later version.
    10	
    11	// This library is distributed in the hope that it will be useful,
    12	// but WITHOUT ANY WARRANTY; without even the implied warranty of
    13	// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    14	// GNU General Public License for more details.
    15	
    16	// Under Section 7 of GPL version 3, you are granted additional
    17	// permissions described in the GCC Runtime Library Exception, version
    18	// 3.1, as published by the Free Software Foundation.
    19	
    20	// You should have received a copy of the GNU General Public License and
    21	// a copy of the GCC Runtime Library Exception along with this program;
    22	// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
    23	// <http://www.gnu.org/licenses/>.
    24	
    25	/**
    26	 *  @file bits/regex_automaton.tcc
    27	 *  This is an internal header file, included by other library headers.
    28	 *  Do not attempt to use it directly. @headername{regex}
    29	 */
    30	
    31	namespace std _GLIBCXX_VISIBILITY(default)
    32	{
    33	_GLIBCXX_BEGIN_NAMESPACE_VERSION
    34	
    35	namespace __detail
    36	{
    37	#ifdef _GLIBCXX_DEBUG
    38	  inline std::ostream&
    39	  _State_base::_M_print(std::ostream& ostr) const
    40	  {
    41	    switch (_M_opcode)
    42	    {
    43	      case _S_opcode_alternative:
    44	      case _S_opcode_repeat:
    45		ostr << "alt next=" << _M_next << " alt=" << _M_alt;
    46		break;
    47	      case _S_opcode_subexpr_begin:
    48		ostr << "subexpr begin next=" << _M_next << " index=" << _M_subexpr;
    49		break;
    50	      case _S_opcode_subexpr_end:
    51		ostr << "subexpr end next=" << _M_next << " index=" << _M_subexpr;
    52		break;
    53	      case _S_opcode_backref:
    54		ostr << "backref next=" << _M_next << " index=" << _M_backref_index;
    55		break;
    56	      case _S_opcode_match:
    57		ostr << "match next=" << _M_next;
    58		break;
    59	      case _S_opcode_accept:
    60		ostr << "accept next=" << _M_next;
    61		break;
    62	      default:
    63		ostr << "unknown next=" << _M_next;
    64		break;
    65	    }
    66	    return ostr;
    67	  }
    68	
    69	  // Prints graphviz dot commands for state.
    70	  inline std::ostream&
    71	  _State_base::_M_dot(std::ostream& __ostr, _StateIdT __id) const
    72	  {
    73	    switch (_M_opcode)
    74	    {
    75	      case _S_opcode_alternative:
    76	      case _S_opcode_repeat:
    77		__ostr << __id << " [label=\"" << __id << "\\nALT\"];\n"
    78		       << __id << " -> " << _M_next
    79		       << " [label=\"next\", tailport=\"s\"];\n"
    80		       << __id << " -> " << _M_alt
    81		       << " [label=\"alt\", tailport=\"n\"];\n";
    82		break;
    83	      case _S_opcode_backref:
    84		__ostr << __id << " [label=\"" << __id << "\\nBACKREF "
    85		       << _M_subexpr << "\"];\n"
    86		       << __id << " -> " << _M_next << " [label=\"<match>\"];\n";
    87		break;
    88	      case _S_opcode_line_begin_assertion:
    89		__ostr << __id << " [label=\"" << __id << "\\nLINE_BEGIN \"];\n"
    90		       << __id << " -> " << _M_next << " [label=\"epsilon\"];\n";
    91		break;
    92	      case _S_opcode_line_end_assertion:
    93		__ostr << __id << " [label=\"" << __id << "\\nLINE_END \"];\n"
    94		       << __id << " -> " << _M_next << " [label=\"epsilon\"];\n";
    95		break;
    96	      case _S_opcode_word_boundary:
    97		__ostr << __id << " [label=\"" << __id << "\\nWORD_BOUNDRY "
    98		       << _M_neg << "\"];\n"
    99		       << __id << " -> " << _M_next << " [label=\"epsilon\"];\n";
   100		break;
   101	      case _S_opcode_subexpr_lookahead:
   102		__ostr << __id << " [label=\"" << __id << "\\nLOOK_AHEAD\"];\n"
   103		       << __id << " -> " << _M_next
   104		       << " [label=\"epsilon\", tailport=\"s\"];\n"
   105		       << __id << " -> " << _M_alt
   106		       << " [label=\"<assert>\", tailport=\"n\"];\n";
   107		break;
   108	      case _S_opcode_subexpr_begin:
   109		__ostr << __id << " [label=\"" << __id << "\\nSBEGIN "
   110		       << _M_subexpr << "\"];\n"
   111		       << __id << " -> " << _M_next << " [label=\"epsilon\"];\n";
   112		break;
   113	      case _S_opcode_subexpr_end:
   114		__ostr << __id << " [label=\"" << __id << "\\nSEND "
   115		       << _M_subexpr << "\"];\n"
   116		       << __id << " -> " << _M_next << " [label=\"epsilon\"];\n";
   117		break;
   118	      case _S_opcode_dummy:
   119		break;
   120	      case _S_opcode_match:
   121		__ostr << __id << " [label=\"" << __id << "\\nMATCH\"];\n"
   122		       << __id << " -> " << _M_next << " [label=\"<match>\"];\n";
   123		break;
   124	      case _S_opcode_accept:
   125		__ostr << __id << " [label=\"" << __id << "\\nACC\"];\n" ;
   126		break;
   127	      default:
   128		_GLIBCXX_DEBUG_ASSERT(false);
   129		break;
   130	    }
   131	    return __ostr;
   132	  }
   133	
   134	  template<typename _TraitsT>
   135	    std::ostream&
   136	    _NFA<_TraitsT>::_M_dot(std::ostream& __ostr) const
   137	    {
   138	      __ostr << "digraph _Nfa {\n"
   139			"  rankdir=LR;\n";
   140	      for (size_t __i = 0; __i < this->size(); ++__i)
   141		(*this)[__i]._M_dot(__ostr, __i);
   142	      __ostr << "}\n";
   143	      return __ostr;
   144	    }
   145	#endif
   146	
   147	  template<typename _TraitsT>
   148	    _StateIdT
   149	    _NFA<_TraitsT>::_M_insert_backref(size_t __index)
   150	    {
   151	      if (this->_M_flags & regex_constants::__polynomial)
   152		__throw_regex_error(regex_constants::error_complexity,
   153				    "Unexpected back-reference in polynomial mode.");
   154	      // To figure out whether a backref is valid, a stack is used to store
   155	      // unfinished sub-expressions. For example, when parsing
   156	      // "(a(b)(c\\1(d)))" at '\\1', _M_subexpr_count is 3, indicating that 3
   157	      // sub expressions are parsed or partially parsed(in the stack), aka,
   158	      // "(a..", "(b)" and "(c..").
   159	      // _M_paren_stack is {1, 3}, for incomplete "(a.." and "(c..". At this
   160	      // time, "\\2" is valid, but "\\1" and "\\3" are not.
   161	      if (__index >= _M_subexpr_count)
   162		__throw_regex_error(
   163		  regex_constants::error_backref,
   164		  "Back-reference index exceeds current sub-expression count.");
   165	      for (auto __it : this->_M_paren_stack)
   166		if (__index == __it)
   167		  __throw_regex_error(
   168		    regex_constants::error_backref,
   169		    "Back-reference referred to an opened sub-expression.");
   170	      this->_M_has_backref = true;
   171	      _StateT __tmp(_S_opcode_backref);
   172	      __tmp._M_backref_index = __index;
   173	      return _M_insert_state(std::move(__tmp));
   174	    }
   175	
   176	  template<typename _TraitsT>
   177	    void
   178	    _NFA<_TraitsT>::_M_eliminate_dummy()
   179	    {
   180	      for (auto& __it : *this)
   181		{
   182		  while (__it._M_next >= 0 && (*this)[__it._M_next]._M_opcode()
   183			 == _S_opcode_dummy)
   184		    __it._M_next = (*this)[__it._M_next]._M_next;
   185		  if (__it._M_has_alt())
   186		    while (__it._M_alt >= 0 && (*this)[__it._M_alt]._M_opcode()
   187			   == _S_opcode_dummy)
   188		      __it._M_alt = (*this)[__it._M_alt]._M_next;
   189		}
   190	    }
   191	
   192	  // Just apply DFS on the sequence and re-link their links.
   193	  template<typename _TraitsT>
   194	    _StateSeq<_TraitsT>
   195	    _StateSeq<_TraitsT>::_M_clone()
   196	    {
   197	      std::map<_StateIdT, _StateIdT> __m;
   198	      std::stack<_StateIdT> __stack;
   199	      __stack.push(_M_start);
   200	      while (!__stack.empty())
   201		{
   202		  auto __u = __stack.top();
   203		  __stack.pop();
   204		  auto __dup = _M_nfa[__u];
   205		  // _M_insert_state() never return -1
   206		  auto __id = _M_nfa._M_insert_state(std::move(__dup));
   207		  __m[__u] = __id;
   208		  if (__dup._M_has_alt())
   209		    if (__dup._M_alt != _S_invalid_state_id
   210			&& __m.count(__dup._M_alt) == 0)
   211		      __stack.push(__dup._M_alt);
   212		  if (__u == _M_end)
   213		    continue;
   214		  if (__dup._M_next != _S_invalid_state_id
   215		      && __m.count(__dup._M_next) == 0)
   216		    __stack.push(__dup._M_next);
   217		}
   218	      for (auto __it : __m)
   219		{
   220		  auto __v = __it.second;
   221		  auto& __ref = _M_nfa[__v];
   222		  if (__ref._M_next != _S_invalid_state_id)
   223		    __ref._M_next = __m.find(__ref._M_next)->second;
   224		  if (__ref._M_has_alt() && __ref._M_alt != _S_invalid_state_id)
   225		    __ref._M_alt = __m.find(__ref._M_alt)->second;
   226		}
   227	      return _StateSeq(_M_nfa, __m[_M_start], __m[_M_end]);
   228	    }
   229	} // namespace __detail
   230	
   231	_GLIBCXX_END_NAMESPACE_VERSION
   232	} // namespace