Merged regex-4 branch.

[SVN r18430]

include/boost/regex/v4/perl_matcher_recursive.hpp

@@ -0,0 +1,661 @@
+/*
+ *
+ * Copyright (c) 2002
+ * Dr John Maddock
+ *
+ * Permission to use, copy, modify, distribute and sell this software
+ * and its documentation for any purpose is hereby granted without fee,
+ * provided that the above copyright notice appear in all copies and
+ * that both that copyright notice and this permission notice appear
+ * in supporting documentation.  Dr John Maddock makes no representations
+ * about the suitability of this software for any purpose.
+ * It is provided "as is" without express or implied warranty.
+ *
+ */
+
+ /*
+  *   LOCATION:    see http://www.boost.org for most recent version.
+  *   FILE         perl_matcher_common.cpp
+  *   VERSION      see <boost/version.hpp>
+  *   DESCRIPTION: Definitions of perl_matcher member functions that are 
+  *                specific to the recursive implementation.
+  */
+
+#ifndef BOOST_REGEX_V4_PERL_MATCHER_RECURSIVE_HPP
+#define BOOST_REGEX_V4_PERL_MATCHER_RECURSIVE_HPP
+
+#ifdef __BORLANDC__
+#  pragma option push -a8 -b -Vx -Ve -pc -w-8027 -w-8066 -w-8008
+#endif
+
+namespace boost{
+namespace re_detail{
+
+template <class BidiIterator>
+class backup_subex
+{
+   int index;
+   sub_match<BidiIterator> sub;
+public:
+   template <class A>
+   backup_subex(const match_results<BidiIterator, A>& w, int i)
+      : index(i), sub(w[i]) {}
+   template <class A>
+   void restore(match_results<BidiIterator, A>& w)
+   {
+      w.set_first(sub.first, index);
+      w.set_second(sub.second, index, sub.matched);
+   }
+};
+
+template <class BidiIterator, class Allocator, class traits, class Allocator2>
+bool perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_all_states()
+{
+   if(state_count > max_state_count)
+      raise_error(traits_inst, REG_ESPACE);
+   while(pstate)
+   {
+      matcher_proc_type proc = s_match_vtable[pstate->type];
+      ++state_count;
+      if(!(this->*proc)())
+      {
+         if((m_match_flags & match_partial) && (position == last))
+            m_has_partial_match = true;
+         return 0;
+      }
+   }
+   return true;
+}
+
+template <class BidiIterator, class Allocator, class traits, class Allocator2>
+bool perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_startmark()
+{
+   int index = static_cast<const re_brace*>(pstate)->index;
+   bool r = true;
+   switch(index)
+   {
+   case 0:
+      pstate = pstate->next.p;
+      break;
+   case -1:
+   case -2:
+      {
+         // forward lookahead assert:
+         BidiIterator old_position(position);
+         const re_syntax_base* next_pstate = static_cast<const re_jump*>(pstate->next.p)->alt.p->next.p;
+         pstate = pstate->next.p->next.p;
+         r = match_all_states();
+         pstate = next_pstate;
+         position = old_position;
+         if((r && (index != -1)) || (!r && (index != -2)))
+            r = false;
+         else
+            r = true;
+         break;
+      }
+   case -3:
+      {
+         // independent sub-expression:
+         const re_syntax_base* next_pstate = static_cast<const re_jump*>(pstate->next.p)->alt.p->next.p;
+         pstate = pstate->next.p->next.p;
+         r = match_all_states();
+         pstate = next_pstate;
+         break;
+      }
+   default:
+   {
+      assert(index > 0);
+      if((m_match_flags & match_nosubs) == 0)
+      {
+         backup_subex<BidiIterator> sub(*m_presult, index);
+         m_presult->set_first(position, index);
+         pstate = pstate->next.p;
+         r = match_all_states();
+         if(r == false)
+            sub.restore(*m_presult);
+      }
+      else
+      {
+         pstate = pstate->next.p;
+      }
+      break;
+   }
+   }
+   return r;
+}
+
+template <class BidiIterator, class Allocator, class traits, class Allocator2>
+bool perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_alt()
+{
+   bool take_first, take_second;
+   const re_jump* jmp = static_cast<const re_jump*>(pstate);
+
+   // find out which of these two alternatives we need to take:
+   if(position == last)
+   {
+      take_first = jmp->can_be_null & mask_take;
+      take_second = jmp->can_be_null & mask_skip;
+   }
+   else
+   {
+      take_first = access::can_start(*position, jmp->_map, (unsigned char)mask_take);
+      take_second = access::can_start(*position, jmp->_map, (unsigned char)mask_skip);
+  }
+
+   if(take_first)
+   {
+      // we can take the first alternative,
+      // see if we need to push next alternative:
+      if(take_second)
+      {
+         BidiIterator oldposition(position);
+         const re_syntax_base* old_pstate = jmp->alt.p;
+         pstate = pstate->next.p;
+         if(!match_all_states())
+         {
+            pstate = old_pstate;
+            position = oldposition;
+         }
+         return true;
+      }
+      pstate = pstate->next.p;
+      return true;
+   }
+   if(take_second)
+   {
+      pstate = jmp->alt.p;
+      return true;
+   }
+   return false;  // neither option is possible
+}
+
+template <class BidiIterator, class Allocator, class traits, class Allocator2>
+bool perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_rep()
+{
+#ifdef BOOST_MSVC
+#pragma warning(push)
+#pragma warning(disable:4127 4244)
+#endif
+   const re_repeat* rep = static_cast<const re_repeat*>(pstate);
+   if(next_count->get_id() != rep->id)
+   {
+      // we're moving to a different repeat from the last
+      // one, so set up a counter object and recurse:
+      repeater_count<BidiIterator> r(rep->id, &next_count, position);
+      return match_rep();
+   }
+   //
+   // If we've had at least one repeat already, and the last one 
+   // matched the NULL string then set the repeat count to
+   // maximum:
+   //
+   next_count->check_null_repeat(position, rep->max);
+
+   // find out which of these two alternatives we need to take:
+   bool take_first, take_second;
+   if(position == last)
+   {
+      take_first = rep->can_be_null & mask_take;
+      take_second = rep->can_be_null & mask_skip;
+   }
+   else
+   {
+      take_first = access::can_start(*position, rep->_map, (unsigned char)mask_take);
+      take_second = access::can_start(*position, rep->_map, (unsigned char)mask_skip);
+   }
+
+   if(next_count->get_count() < rep->min)
+   {
+      // we must take the repeat:
+      if(take_first)
+      {
+         // increase the counter:
+         ++(*next_count);
+         pstate = rep->next.p;
+         return match_all_states();
+      }
+      return false;
+   }
+
+   if(rep->greedy)
+   {
+      // try and take the repeat if we can:
+      if((next_count->get_count() < rep->max) && take_first)
+      {
+         // store position in case we fail:
+         BidiIterator pos = position;
+         // increase the counter:
+         ++(*next_count);
+         pstate = rep->next.p;
+         if(match_all_states())
+            return true;
+         // failed repeat, reset posistion and fall through for alternative:
+         position = pos;
+      }
+      if(take_second)
+      {
+         pstate = rep->alt.p;
+         return true;
+      }
+      return false; // can't take anything, fail...
+   }
+   else // non-greedy
+   {
+      // try and skip the repeat if we can:
+      if(take_second)
+      {
+         // store position in case we fail:
+         BidiIterator pos = position;
+         pstate = rep->alt.p;
+         if(match_all_states())
+            return true;
+         // failed alternative, reset posistion and fall through for repeat:
+         position = pos;
+      }
+      if((next_count->get_count() < rep->max) && take_first)
+      {
+         // increase the counter:
+         ++(*next_count);
+         pstate = rep->next.p;
+         return match_all_states();
+      }
+   }
+   return false;
+#ifdef BOOST_MSVC
+#pragma warning(pop)
+#endif
+}
+
+template <class BidiIterator, class Allocator, class traits, class Allocator2>
+bool perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_dot_repeat_slow()
+{
+#ifdef BOOST_MSVC
+#pragma warning(push)
+#pragma warning(disable:4127)
+#endif
+   unsigned count = 0;
+   const re_repeat* rep = static_cast<const re_repeat*>(pstate);
+   re_syntax_base* psingle = rep->next.p;
+   // match compulsary repeats first:
+   while(count < rep->min)
+   {
+      pstate = psingle;
+      if(!match_wild())
+         return false;
+      ++count;
+   }
+   if(rep->greedy)
+   {
+      // normal repeat:
+      while(count < rep->max)
+      {
+         pstate = psingle;
+         if(!match_wild())
+            break;
+         ++count;
+      }
+      if((rep->leading) && (count < rep->max))
+         restart = position;
+      pstate = rep;
+      return backtrack_till_match(count - rep->min);
+   }
+   else
+   {
+      // non-greedy, keep trying till we get a match:
+      BidiIterator save_pos;
+      do
+      {
+         if((rep->leading) && (rep->max == UINT_MAX))
+            restart = position;
+         pstate = rep->alt.p;
+         save_pos = position;
+         ++state_count;
+         if(match_all_states())
+            return true;
+         if(count >= rep->max)
+            return false;
+         ++count;
+         pstate = psingle;
+         position = save_pos;
+         if(!match_wild())
+            return false;
+      }while(true);
+   }
+#ifdef BOOST_MSVC
+#pragma warning(pop)
+#endif
+}
+
+template <class BidiIterator, class Allocator, class traits, class Allocator2>
+bool perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_dot_repeat_fast()
+{
+#ifdef BOOST_MSVC
+#pragma warning(push)
+#pragma warning(disable:4127)
+#endif
+   if(m_match_flags & (match_not_dot_newline | match_not_dot_null))
+      return match_dot_repeat_slow();
+   //
+   // start by working out how much we can skip:
+   //
+   const re_repeat* rep = static_cast<const re_repeat*>(pstate);
+   unsigned count = std::min(static_cast<unsigned>(re_detail::distance(position, last)), (rep->greedy ? rep->max : rep->min));
+   if(rep->min > count)
+      return false;  // not enough text left to match
+   std::advance(position, count);
+   if((rep->leading) && (count < rep->max) && (rep->greedy))
+      restart = position;
+   if(rep->greedy)
+      return backtrack_till_match(count - rep->min);
+
+   // non-greedy, keep trying till we get a match:
+   BidiIterator save_pos;
+   do
+   {
+      while((position != last) && (count < rep->max) && !access::can_start(*position, rep->_map, mask_skip))
+      {
+         ++position;
+         ++count;
+      }
+      if((rep->leading) && (count == UINT_MAX))
+         restart = position;
+      pstate = rep->alt.p;
+      save_pos = position;
+      ++state_count;
+      if(match_all_states())
+         return true;
+      if(count >= rep->max)
+         return false;
+      if(position == last)
+         return false;
+      position = ++save_pos;
+      ++count;
+   }while(true);
+#ifdef BOOST_MSVC
+#pragma warning(pop)
+#endif
+}
+
+template <class BidiIterator, class Allocator, class traits, class Allocator2>
+bool perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_char_repeat()
+{
+#ifdef BOOST_MSVC
+#pragma warning(push)
+#pragma warning(disable:4127)
+#endif
+   const re_repeat* rep = static_cast<const re_repeat*>(pstate);
+   assert(1 == static_cast<const re_literal*>(rep->next.p)->length);
+   const char_type what = *reinterpret_cast<const char_type*>(static_cast<const re_literal*>(rep->next.p) + 1);
+   unsigned count = 0;
+   //
+   // start by working out how much we can skip:
+   //
+   unsigned desired = rep->greedy ? rep->max : rep->min;
+   if(::boost::is_random_access_iterator<BidiIterator>::value)
+   {
+      BidiIterator end = position;
+      end += std::min((unsigned)re_detail::distance(position, last), desired);
+      BidiIterator origin(position);
+      while((position != end) && (traits_inst.translate(*position, icase) == what))
+      {
+         ++position;
+      }
+      count = (unsigned)re_detail::distance(origin, position);
+   }
+   else
+   {
+      while((count < desired) && (position != last) && (traits_inst.translate(*position, icase) == what))
+      {
+         ++position;
+         ++count;
+      }
+   }
+   if((rep->leading) && (count < rep->max) && (rep->greedy))
+      restart = position;
+   if(count < rep->min)
+      return false;
+
+   if(rep->greedy)
+      return backtrack_till_match(count - rep->min);
+
+   // non-greedy, keep trying till we get a match:
+   BidiIterator save_pos;
+   do
+   {
+      while((position != last) && (count < rep->max) && !access::can_start(*position, rep->_map, mask_skip))
+      {
+         if((traits_inst.translate(*position, icase) == what))
+         {
+            ++position;
+            ++count;
+         }
+         else
+            return false;  // counldn't repeat even though it was the only option
+      }
+      if((rep->leading) && (rep->max == UINT_MAX))
+         restart = position;
+      pstate = rep->alt.p;
+      save_pos = position;
+      ++state_count;
+      if(match_all_states())
+         return true;
+      if(count >= rep->max)
+         return false;
+      if(position == last)
+         return false;
+      position = ++save_pos;
+      ++count;
+   }while(true);
+#ifdef BOOST_MSVC
+#pragma warning(pop)
+#endif
+}
+
+template <class BidiIterator, class Allocator, class traits, class Allocator2>
+bool perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_set_repeat()
+{
+#ifdef BOOST_MSVC
+#pragma warning(push)
+#pragma warning(disable:4127)
+#endif
+   const re_repeat* rep = static_cast<const re_repeat*>(pstate);
+   const unsigned char* map = static_cast<const re_set*>(rep->next.p)->_map;
+   unsigned count = 0;
+   //
+   // start by working out how much we can skip:
+   //
+   unsigned desired = rep->greedy ? rep->max : rep->min;
+   if(::boost::is_random_access_iterator<BidiIterator>::value)
+   {
+      BidiIterator end = position;
+      end += std::min((unsigned)re_detail::distance(position, last), desired);
+      BidiIterator origin(position);
+      while((position != end) && map[(traits_uchar_type)traits_inst.translate(*position, icase)])
+      {
+         ++position;
+      }
+      count = (unsigned)re_detail::distance(origin, position);
+   }
+   else
+   {
+      while((count < desired) && (position != last) && map[(traits_uchar_type)traits_inst.translate(*position, icase)])
+      {
+         ++position;
+         ++count;
+      }
+   }
+   if((rep->leading) && (count < rep->max) && (rep->greedy))
+      restart = position;
+   if(count < rep->min)
+      return false;
+
+   if(rep->greedy)
+      return backtrack_till_match(count - rep->min);
+
+   // non-greedy, keep trying till we get a match:
+   BidiIterator save_pos;
+   do
+   {
+      while((position != last) && (count < rep->max) && !access::can_start(*position, rep->_map, mask_skip))
+      {
+         if(map[(traits_uchar_type)traits_inst.translate(*position, icase)])
+         {
+            ++position;
+            ++count;
+         }
+         else
+            return false;  // counldn't repeat even though it was the only option
+      }
+      if((rep->leading) && (rep->max == UINT_MAX))
+         restart = position;
+      pstate = rep->alt.p;
+      save_pos = position;
+      ++state_count;
+      if(match_all_states())
+         return true;
+      if(count >= rep->max)
+         return false;
+      if(position == last)
+         return false;
+      position = ++save_pos;
+      ++count;
+   }while(true);
+#ifdef BOOST_MSVC
+#pragma warning(pop)
+#endif
+}
+
+template <class BidiIterator, class Allocator, class traits, class Allocator2>
+bool perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_long_set_repeat()
+{
+#ifdef BOOST_MSVC
+#pragma warning(push)
+#pragma warning(disable:4127)
+#endif
+   const re_repeat* rep = static_cast<const re_repeat*>(pstate);
+   const re_set_long* set = static_cast<const re_set_long*>(pstate->next.p);
+   unsigned count = 0;
+   //
+   // start by working out how much we can skip:
+   //
+   unsigned desired = rep->greedy ? rep->max : rep->min;
+   if(::boost::is_random_access_iterator<BidiIterator>::value)
+   {
+      BidiIterator end = position;
+      end += std::min((unsigned)re_detail::distance(position, last), desired);
+      BidiIterator origin(position);
+      while((position != end) && (position != re_is_set_member(position, last, set, re)))
+      {
+         ++position;
+      }
+      count = (unsigned)re_detail::distance(origin, position);
+   }
+   else
+   {
+      while((count < desired) && (position != last) && (position != re_is_set_member(position, last, set, re)))
+      {
+         ++position;
+         ++count;
+      }
+   }
+   if((rep->leading) && (count < rep->max) && (rep->greedy))
+      restart = position;
+   if(count < rep->min)
+      return false;
+
+   if(rep->greedy)
+      return backtrack_till_match(count - rep->min);
+
+   // non-greedy, keep trying till we get a match:
+   BidiIterator save_pos;
+   do
+   {
+      while((position != last) && (count < rep->max) && !access::can_start(*position, rep->_map, mask_skip))
+      {
+         if(position != re_is_set_member(position, last, set, re))
+         {
+            ++position;
+            ++count;
+         }
+         else
+            return false;  // counldn't repeat even though it was the only option
+      }
+      if((rep->leading) && (rep->max == UINT_MAX))
+         restart = position;
+      pstate = rep->alt.p;
+      save_pos = position;
+      ++state_count;
+      if(match_all_states())
+         return true;
+      if(count >= rep->max)
+         return false;
+      if(position == last)
+         return false;
+      position = ++save_pos;
+      ++count;
+   }while(true);
+#ifdef BOOST_MSVC
+#pragma warning(pop)
+#endif
+}
+
+template <class BidiIterator, class Allocator, class traits, class Allocator2>
+bool perl_matcher<BidiIterator, Allocator, traits, Allocator2>::backtrack_till_match(unsigned count)
+{
+#ifdef BOOST_MSVC
+#pragma warning(push)
+#pragma warning(disable:4127)
+#endif
+   if((m_match_flags & match_partial) && (position == last))
+      m_has_partial_match = true;
+
+   const re_repeat* rep = static_cast<const re_repeat*>(pstate);
+   BidiIterator backtrack = position;
+   if(position == last)
+   {
+      if(rep->can_be_null & mask_skip) 
+      {
+         pstate = rep->alt.p;
+         if(match_all_states())
+            return true;
+      }
+      if(count)
+      {
+         position = --backtrack;
+         --count;
+      }
+      else
+         return false;
+   }
+   do
+   {
+      while(count && !access::can_start(*position, rep->_map, mask_skip))
+      {
+         --position;
+         --count;
+         ++state_count;
+      }
+      pstate = rep->alt.p;
+      backtrack = position;
+      if(match_all_states())
+         return true;
+      if(count == 0)
+         return false;
+      position = --backtrack;
+      ++state_count;
+      --count;
+   }while(true);
+#ifdef BOOST_MSVC
+#pragma warning(pop)
+#endif
+}
+
+} // namespace re_detail
+} // namespace boost
+
+
+#ifdef __BORLANDC__
+#  pragma option pop
+#endif
+
+#endif