2011-09-14 François Dumont <fdumont@gcc.gnu.org>

[pf3gnuchains/gcc-fork.git] / libstdc++-v3 / include / bits / hashtable.h

diff --git a/libstdc++-v3/include/bits/hashtable.h b/libstdc++-v3/include/bits/hashtable.h
index ed9bdb3..b097ee7 100644 (file)
--- a/libstdc++-v3/include/bits/hashtable.h
+++ b/libstdc++-v3/include/bits/hashtable.h
@@ -458,8 +458,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       // reserve, if present, comes from _Rehash_base.
 
     private:
-      // Unconditionally change size of bucket array to n.
-      void _M_rehash(size_type __n);
+      // Unconditionally change size of bucket array to n, restore hash policy
+      // resize value to __next_resize on exception.
+      void _M_rehash(size_type __n, size_type __next_resize);
     };
 
 
@@ -743,7 +744,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       _M_rehash_policy = __pol;
       size_type __n_bkt = __pol._M_bkt_for_elements(_M_element_count);
       if (__n_bkt > _M_bucket_count)
-       _M_rehash(__n_bkt);
+       _M_rehash(__n_bkt, __pol._M_next_resize);
     }
 
   template<typename _Key, typename _Value,
@@ -910,6 +911,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       _M_insert_bucket(_Arg&& __v, size_type __n,
                       typename _Hashtable::_Hash_code_type __code)
       {
+       const size_type __saved_next_resize = _M_rehash_policy._M_next_resize;
        std::pair<bool, std::size_t> __do_rehash
          = _M_rehash_policy._M_need_rehash(_M_bucket_count,
                                            _M_element_count, 1);
@@ -920,14 +922,14 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
            __n = this->_M_bucket_index(__k, __code, __do_rehash.second);
          }
 
-       // Allocate the new node before doing the rehash so that we don't
-       // do a rehash if the allocation throws.
-       _Node* __new_node = _M_allocate_node(std::forward<_Arg>(__v));
-
+       _Node* __new_node = 0;
        __try
          {
+           // Allocate the new node before doing the rehash so that we
+           // don't do a rehash if the allocation throws.
+           __new_node = _M_allocate_node(std::forward<_Arg>(__v));
            if (__do_rehash.first)
-             _M_rehash(__do_rehash.second);
+             _M_rehash(__do_rehash.second, __saved_next_resize);
 
            __new_node->_M_next = _M_buckets[__n];
            this->_M_store_code(__new_node, __code);
@@ -939,7 +941,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
          }
        __catch(...)
          {
-           _M_deallocate_node(__new_node);
+           if (!__new_node)
+             _M_rehash_policy._M_next_resize = __saved_next_resize;
+           else
+             _M_deallocate_node(__new_node);
            __throw_exception_again;
          }
       }
@@ -981,11 +986,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
                 _H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
       _M_insert(_Arg&& __v, std::false_type)
       {
+       const size_type __saved_next_resize = _M_rehash_policy._M_next_resize;
        std::pair<bool, std::size_t> __do_rehash
          = _M_rehash_policy._M_need_rehash(_M_bucket_count,
                                            _M_element_count, 1);
        if (__do_rehash.first)
-         _M_rehash(__do_rehash.second);
+         _M_rehash(__do_rehash.second, __saved_next_resize);
 
        const key_type& __k = this->_M_extract(__v);
        typename _Hashtable::_Hash_code_type __code = this->_M_hash_code(__k);
@@ -1024,11 +1030,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       insert(_InputIterator __first, _InputIterator __last)
       {
        size_type __n_elt = __detail::__distance_fw(__first, __last);
+       const size_type __saved_next_resize = _M_rehash_policy._M_next_resize;
        std::pair<bool, std::size_t> __do_rehash
          = _M_rehash_policy._M_need_rehash(_M_bucket_count,
                                            _M_element_count, __n_elt);
        if (__do_rehash.first)
-         _M_rehash(__do_rehash.second);
+         _M_rehash(__do_rehash.second, __saved_next_resize);
 
        for (; __first != __last; ++__first)
          this->insert(*__first);
@@ -1184,9 +1191,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
               _H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
     rehash(size_type __n)
     {
+      const size_type __saved_next_resize = _M_rehash_policy._M_next_resize;
       _M_rehash(std::max(_M_rehash_policy._M_next_bkt(__n),
                         _M_rehash_policy._M_bkt_for_elements(_M_element_count
-                                                             + 1)));
+                                                             + 1)),
+               __saved_next_resize);
     }
 
   template<typename _Key, typename _Value,
@@ -1196,11 +1205,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     void
     _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
               _H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
-    _M_rehash(size_type __n)
+    _M_rehash(size_type __n, size_type __next_resize)
     {
-      _Node** __new_array = _M_allocate_buckets(__n);
+      _Node** __new_array = 0;
       __try
        {
+         __new_array = _M_allocate_buckets(__n);
          _M_begin_bucket_index = __n;
          for (size_type __i = 0; __i < _M_bucket_count; ++__i)
            while (_Node* __p = _M_buckets[__i])
@@ -1218,15 +1228,23 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
        }
       __catch(...)
        {
-         // A failure here means that a hash function threw an exception.
-         // We can't restore the previous state without calling the hash
-         // function again, so the only sensible recovery is to delete
-         // everything.
-         _M_deallocate_nodes(__new_array, __n);
-         _M_deallocate_buckets(__new_array, __n);
-         _M_deallocate_nodes(_M_buckets, _M_bucket_count);
-         _M_element_count = 0;
-         _M_begin_bucket_index = _M_bucket_count;
+         if (__new_array)
+           {
+             // A failure here means that a hash function threw an exception.
+             // We can't restore the previous state without calling the hash
+             // function again, so the only sensible recovery is to delete
+             // everything.
+             _M_deallocate_nodes(__new_array, __n);
+             _M_deallocate_buckets(__new_array, __n);
+             _M_deallocate_nodes(_M_buckets, _M_bucket_count);
+             _M_element_count = 0;
+             _M_begin_bucket_index = _M_bucket_count;
+             _M_rehash_policy._M_next_resize = 0;
+           }
+         else
+           // A failure here means that buckets allocation failed.  We only
+           // have to restore hash policy previous state.
+           _M_rehash_policy._M_next_resize = __next_resize;
          __throw_exception_again;
        }
     }