more or less completed non-recursive implementation.

[SVN r18185]

include/boost/regex/config.hpp

@@ -468,10 +468,9 @@ void raise_error(const traits& t, unsigned code)
 #  ifdef BOOST_REGEX_HAS_MS_STACK_GUARD
 #     undef BOOST_REGEX_HAS_MS_STACK_GUARD
 #  endif
-namespace boost{ namespace re_detail{
-BOOST_REGEX_DECL void* BOOST_REGEX_CALL get_mem_block();
-BOOST_REGEX_DECL void BOOST_REGEX_CALL release_mem_block(void*);
-} }
+#  ifndef BOOST_REGEX_MAX_CACHE_BLOCKS
+#     define BOOST_REGEX_MAX_CACHE_BLOCKS BOOST_REGEX_MAX_BLOCKS
+#  endif
 #endif
 
 

include/boost/regex/user.hpp

@@ -77,3 +77,9 @@
 // used by the non-recursive algorithm.
 // #define BOOST_REGEX_MAX_BLOCKS 1024
 
+// define this if you want to set the maximum number of memory blocks
+// cached by the non-recursive algorithm: Normally this is the same as 
+// BOOST_REGEX_MAX_BLOCKS, but can be higher if you have multiple threads
+// all using boost.regex, or lower if you don't want boost.regex to cache
+// memory.
+// #define BOOST_REGEX_MAX_CACHE_BLOCKS 1024

include/boost/regex/v4/mem_block_cache.hpp

@@ -16,14 +16,14 @@
   *   LOCATION:    see http://www.boost.org for most recent version.
   *   FILE         mem_block_cache.hpp
   *   VERSION      see <boost/version.hpp>
-  *   DESCRIPTION: Definitions of perl_matcher member functions that are 
-  *                specific to the non-recursive implementation.
+  *   DESCRIPTION: memory block cache used by the non-recursive matcher.
   */
 
 #ifndef BOOST_REGEX_V4_MEM_BLOCK_CACHE_HPP
 #define BOOST_REGEX_V4_MEM_BLOCK_CACHE_HPP
 
 #include <new>
+#include <boost/regex/v4/regex_synch.hpp>
 
 #ifdef __BORLANDC__
 #  pragma option push -a8 -b -Vx -Ve -pc -w-8027
@@ -39,7 +39,9 @@ struct mem_block_node
 
 struct mem_block_cache
 {
+   // this member has to be statically initialsed:
    mem_block_node* next;
+   unsigned cached_blocks;
 
    ~mem_block_cache()
    {
@@ -52,19 +54,33 @@ struct mem_block_cache
    }
    void* get()
    {
-      if(next)
+#ifdef BOOST_HAS_THREADS
+      re_detail::cs_guard g(*re_detail::p_re_lock);
+#endif
+     if(next)
       {
          mem_block_node* result = next;
          next = next->next;
+         --cached_blocks;
          return result;
       }
       return ::operator new(BOOST_REGEX_BLOCKSIZE);
    }
    void put(void* p)
    {
-      mem_block_node* old = static_cast<mem_block_node*>(p);
-      old->next = next;
-      next = old;
+#ifdef BOOST_HAS_THREADS
+      re_detail::cs_guard g(*re_detail::p_re_lock);
+#endif
+      if(cached_blocks >= BOOST_REGEX_MAX_CACHE_BLOCKS)
+      {
+         ::operator delete(p);
+      }
+      else
+      {
+         mem_block_node* old = static_cast<mem_block_node*>(p);
+         old->next = next;
+         next = old;
+      }
    }
 };
 

include/boost/regex/v4/perl_matcher.hpp

@@ -384,6 +384,7 @@ private:
    bool unwind_char_repeat(bool);
    bool unwind_short_set_repeat(bool);
    bool unwind_long_set_repeat(bool);
+   bool unwind_non_greedy_repeat(bool);
    void destroy_single_repeat();
    void push_matched_paren(int index, const sub_match<BidiIterator>& sub);
    void push_recursion_stopper();
@@ -391,6 +392,7 @@ private:
    void push_alt(const re_syntax_base* ps);
    void push_repeater_count(int i, repeater_count<BidiIterator>** s);
    void push_single_repeat(unsigned c, const re_repeat* r, BidiIterator last_position, int id);
+   void push_non_greedy_repeat(const re_syntax_base* ps);
 
 
    // pointer to base of stack:

include/boost/regex/v4/perl_matcher_common.hpp

@@ -97,6 +97,7 @@ bool perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match()
 #ifdef BOOST_REGEX_NON_RECURSIVE
    save_state_init init(&m_stack_base, &m_backup_state);
    used_block_count = BOOST_REGEX_MAX_BLOCKS;
+   try{
 #endif
 
    // reset our state machine:
@@ -111,6 +112,17 @@ bool perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match()
       return false;
    return m_result[0].second == last;
 
+#ifdef BOOST_REGEX_NON_RECURSIVE
+   }
+   catch(...)
+   {
+      // unwind all pushed states, apart from anything else this
+      // ensures that all the states are correctly destructed
+      // not just the memory freed.
+      while(unwind(true)){}
+      throw;
+   }
+#endif
 #ifdef BOOST_REGEX_HAS_MS_STACK_GUARD
    }__except(EXCEPTION_STACK_OVERFLOW == GetExceptionCode())
    {
@@ -134,6 +146,7 @@ bool perl_matcher<BidiIterator, Allocator, traits, Allocator2>::find()
 #ifdef BOOST_REGEX_NON_RECURSIVE
    save_state_init init(&m_stack_base, &m_backup_state);
    used_block_count = BOOST_REGEX_MAX_BLOCKS;
+   try{
 #endif
 
    state_count = 0;
@@ -180,6 +193,17 @@ bool perl_matcher<BidiIterator, Allocator, traits, Allocator2>::find()
    matcher_proc_type proc = s_find_vtable[type];
    return (this->*proc)();
 
+#ifdef BOOST_REGEX_NON_RECURSIVE
+   }
+   catch(...)
+   {
+      // unwind all pushed states, apart from anything else this
+      // ensures that all the states are correctly destructed
+      // not just the memory freed.
+      while(unwind(true)){}
+      throw;
+   }
+#endif
 #ifdef BOOST_REGEX_HAS_MS_STACK_GUARD
    }__except(EXCEPTION_STACK_OVERFLOW == GetExceptionCode())
    {
@@ -755,6 +779,12 @@ perl_matcher<BidiIterator, Allocator, traits, Allocator2>::s_match_vtable[] =
    &perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_combining,
    &perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_soft_buffer_end,
    &perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_restart_continue,
+#if 0
+   &perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_rep,
+   &perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_rep,
+   &perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_rep,
+   &perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_rep,
+#else
 #if defined(BOOST_MSVC) && (BOOST_MSVC <= 1300)
    &perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_dot_repeat_fast,
 #else
@@ -763,7 +793,7 @@ perl_matcher<BidiIterator, Allocator, traits, Allocator2>::s_match_vtable[] =
    &perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_char_repeat,
    &perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_set_repeat,
    &perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_long_set_repeat,
-
+#endif
 };
 
 template <class BidiIterator, class Allocator, class traits, class Allocator2>

include/boost/regex/v4/perl_matcher_non_recursive.hpp

@@ -54,7 +54,8 @@ enum saved_state_type
    saved_state_rep_fast_dot = 9,
    saved_state_rep_char = 10,
    saved_state_rep_short_set = 11,
-   saved_state_rep_long_set = 12
+   saved_state_rep_long_set = 12,
+   saved_state_non_greedy_long_repeat = 13
 };
 
 struct saved_state
@@ -134,8 +135,6 @@ struct saved_single_repeat : public saved_state
 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);
    push_recursion_stopper();
    do{
       while(pstate)
@@ -144,6 +143,8 @@ bool perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_all_states
          ++state_count;
          if(!(this->*proc)())
          {
+            if(state_count > max_state_count)
+               raise_error(traits_inst, REG_ESPACE);
             if((m_match_flags & match_partial) && (position == last))
                m_has_partial_match = true;
             if(false == unwind(false))
@@ -235,6 +236,21 @@ inline void perl_matcher<BidiIterator, Allocator, traits, Allocator2>::push_alt(
    m_backup_state = pmp;
 }
 
+template <class BidiIterator, class Allocator, class traits, class Allocator2>
+inline void perl_matcher<BidiIterator, Allocator, traits, Allocator2>::push_non_greedy_repeat(const re_syntax_base* ps)
+{
+   saved_position<BidiIterator>* pmp = static_cast<saved_position<BidiIterator>*>(m_backup_state);
+   --pmp;
+   if(pmp < m_stack_base)
+   {
+      extend_stack();
+      pmp = static_cast<saved_position<BidiIterator>*>(m_backup_state);
+      --pmp;
+   }
+   new (pmp)saved_position<BidiIterator>(ps, position, saved_state_non_greedy_long_repeat);
+   m_backup_state = pmp;
+}
+
 template <class BidiIterator, class Allocator, class traits, class Allocator2>
 inline void perl_matcher<BidiIterator, Allocator, traits, Allocator2>::push_repeater_count(int i, repeater_count<BidiIterator>** s)
 {
@@ -408,19 +424,16 @@ bool perl_matcher<BidiIterator, Allocator, traits, Allocator2>::match_rep()
       if(take_second)
       {
          // store position in case we fail:
-         BidiIterator pos = position;
+         push_non_greedy_repeat(rep->next.p);
          pstate = rep->alt.p;
-         if(match_all_states())
-            return true;
-         // failed alternative, reset posistion and fall through for repeat:
-         position = pos;
+         return true;
       }
       if((next_count->get_count() < rep->max) && take_first)
       {
          // increase the counter:
          ++(*next_count);
          pstate = rep->next.p;
-         return match_all_states();
+         return true;
       }
    }
    return false;
@@ -1114,6 +1127,21 @@ bool perl_matcher<BidiIterator, Allocator, traits, Allocator2>::unwind_long_set_
 	return false;
 }
 
+template <class BidiIterator, class Allocator, class traits, class Allocator2>
+bool perl_matcher<BidiIterator, Allocator, traits, Allocator2>::unwind_non_greedy_repeat(bool r)
+{
+   saved_position<BidiIterator>* pmp = static_cast<saved_position<BidiIterator>*>(m_backup_state);
+   if(!r)
+   {
+      position = pmp->position;
+      pstate = pmp->pstate;
+      ++(*next_count);
+   }
+   destroy(pmp++);
+   m_backup_state = pmp;
+   return r;
+}
+
 template <class BidiIterator, class Allocator, class traits, class Allocator2>
 typename perl_matcher<BidiIterator, Allocator, traits, Allocator2>::unwind_proc_type const
 perl_matcher<BidiIterator, Allocator, traits, Allocator2>::s_unwind_table[] = 
@@ -1131,6 +1159,7 @@ perl_matcher<BidiIterator, Allocator, traits, Allocator2>::s_unwind_table[] =
    &perl_matcher<BidiIterator, Allocator, traits, Allocator2>::unwind_char_repeat,
    &perl_matcher<BidiIterator, Allocator, traits, Allocator2>::unwind_short_set_repeat,
    &perl_matcher<BidiIterator, Allocator, traits, Allocator2>::unwind_long_set_repeat,
+   &perl_matcher<BidiIterator, Allocator, traits, Allocator2>::unwind_non_greedy_repeat,
 };
 
 }