Fix bug that effects recursive expressions combined with repeats.

[SVN r58722]

include/boost/regex/v4/basic_regex_creator.hpp

@@ -811,8 +811,43 @@ void basic_regex_creator<charT, traits>::fixup_recursions(re_syntax_base* state)
             {
                if((p->type == syntax_element_startmark) && (static_cast<re_brace*>(p)->index == id))
                {
+                  //
+                  // We've found the target of the recursion, set the jump target:
+                  //
                   static_cast<re_jump*>(state)->alt.p = p;
                   ok = true;
+                  // 
+                  // Now scan the target for nested repeats:
+                  //
+                  p = p->next.p;
+                  int next_rep_id = 0;
+                  while(p)
+                  {
+                     switch(p->type)
+                     {
+                     case syntax_element_rep:
+                     case syntax_element_dot_rep:
+                     case syntax_element_char_rep:
+                     case syntax_element_short_set_rep:
+                     case syntax_element_long_set_rep:
+                        next_rep_id = static_cast<re_repeat*>(p)->state_id;
+                        break;
+                     case syntax_element_endmark:
+                        if(static_cast<const re_brace*>(p)->index == id)
+                           next_rep_id = -1;
+                        break;
+                     default: 
+                        break;
+                     }
+                     if(next_rep_id)
+                        break;
+                     p = p->next.p;
+                  }
+                  if(next_rep_id > 0)
+                  {
+                     static_cast<re_recurse*>(state)->state_id = next_rep_id - 1;
+                  }
+
                   break;
                }
                p = p->next.p;

include/boost/regex/v4/basic_regex_parser.hpp

@@ -1939,7 +1939,9 @@ bool basic_regex_parser<charT, traits>::parse_perl_extension()
       }
 insert_recursion:
       pb->index = markid = 0;
-      static_cast<re_jump*>(this->append_state(syntax_element_recurse, sizeof(re_jump)))->alt.i = v;
+      re_recurse* pr = static_cast<re_recurse*>(this->append_state(syntax_element_recurse, sizeof(re_recurse)));
+      pr->alt.i = v;
+      pr->state_id = 0;
       static_cast<re_case*>(
             this->append_state(syntax_element_toggle_case, sizeof(re_case))
             )->icase = this->flags() & regbase::icase;

include/boost/regex/v4/perl_matcher.hpp

@@ -277,11 +277,16 @@ public:
       else
       {
          repeater_count* p = next;
-         while(p->state_id != state_id)
+         while(p && (p->state_id != state_id))
             p = p->next;
+         if(p)
+         {
             count = p->count;
             start_pos = p->start_pos;
          }
+         else
+            count = 0;
+      }
    }
    ~repeater_count()
    {

include/boost/regex/v4/perl_matcher_non_recursive.hpp

@@ -904,10 +904,15 @@ bool perl_matcher<BidiIterator, Allocator, traits>::match_recursion()
    }
    recursion_stack[recursion_stack_position].preturn_address = pstate->next.p;
    recursion_stack[recursion_stack_position].results = *m_presult;
+   if(static_cast<const re_recurse*>(pstate)->state_id > 0)
+   {
+      push_repeater_count(static_cast<const re_recurse*>(pstate)->state_id, &next_count);
+   }
    pstate = static_cast<const re_jump*>(pstate)->alt.p;
    recursion_stack[recursion_stack_position].id = static_cast<const re_brace*>(pstate)->index;
    ++recursion_stack_position;
    //BOOST_ASSERT(recursion_stack[recursion_stack_position-1].id);
+
    return true;
 }
 

include/boost/regex/v4/states.hpp

@@ -248,6 +248,14 @@ struct re_repeat : public re_alt
    bool          greedy;    // True if this is a greedy repeat
 };
 
+/*** struct re_recurse ************************************************
+Recurse to a particular subexpression.
+**********************************************************************/
+struct re_recurse : public re_jump
+{
+   int state_id;             // identifier of first nested repeat within the recursion.
+};
+
 /*** enum re_jump_size_type *******************************************
 Provides compiled size of re_jump structure (allowing for trailing alignment).
 We provide this so we know how manybytes to insert when constructing the machine

test/regress/test_perl_ex.cpp

@@ -892,5 +892,9 @@ void test_recursion()
    TEST_REGEX_SEARCH("\\b(?&byte)(\\.(?&byte)){3}(?(DEFINE)(?<byte>2[0-4]\\d|25[0-5]|1\\d\\d|[1-9]?\\d))", perl|mod_x, "10.0.0.0", match_default, make_array(0, 8, 6, 8, -1, -1, -2, -2));
    TEST_REGEX_SEARCH("\\b(?&byte)(\\.(?&byte)){3}(?(DEFINE)(?<byte>2[0-4]\\d|25[0-5]|1\\d\\d|[1-9]?\\d))", perl|mod_x, "10.6", match_default, make_array(-2, -2));
    TEST_REGEX_SEARCH("\\b(?&byte)(\\.(?&byte)){3}(?(DEFINE)(?<byte>2[0-4]\\d|25[0-5]|1\\d\\d|[1-9]?\\d))", perl|mod_x, "455.3.4.5", match_default, make_array(-2, -2));
+
+   // Bugs:
+   TEST_REGEX_SEARCH("namespace\\s+(\\w+)\\s+(\\{(?:[^{}]*(?:(?2)[^{}]*)*)?\\})", perl, "namespace one { namespace two { int foo(); } }", match_default, make_array(0, 46, 10, 13, 14, 46, -2, -2));
+   TEST_REGEX_SEARCH("namespace\\s+(\\w+)\\s+(\\{(?:[^{}]*(?:(?2)[^{}]*)*)?\\})", perl, "namespace one { namespace two { int foo(){} } { {{{ }  } } } {}}", match_default, make_array(0, 64, 10, 13, 14, 64, -2, -2));
 }