?? stl_alloc.c
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/*
*
* Copyright (c) 1996,1997
* Silicon Graphics Computer Systems, Inc.
*
* Copyright (c) 1997
* Moscow Center for SPARC Technology
*
* Copyright (c) 1999
* Boris Fomitchev
*
* This material is provided "as is", with absolutely no warranty expressed
* or implied. Any use is at your own risk.
*
* Permission to use or copy this software for any purpose is hereby granted
* without fee, provided the above notices are retained on all copies.
* Permission to modify the code and to distribute modified code is granted,
* provided the above notices are retained, and a notice that the code was
* modified is included with the above copyright notice.
*
*/
#ifndef __STL_ALLOC_C
#define __STL_ALLOC_C
// Specialised debug form of malloc which does not provide "false"
// memory leaks when run with debug CRT libraries.
#if defined(__STL_MSVC) && __STL_MSVC>=1020 && defined(_DEBUG)
# include <crtdbg.h>
# define __STL_CHUNK_MALLOC(s) _malloc_dbg(s, _CRT_BLOCK, __FILE__, __LINE__)
#else // !_DEBUG
# ifdef __STL_NODE_ALLOC_USE_MALLOC
# define __STL_CHUNK_MALLOC(s) ::malloc(s)
# else
# define __STL_CHUNK_MALLOC(s) __stl_new(s)
# endif
#endif // !_DEBUG
__STL_BEGIN_NAMESPACE
// malloc_alloc out-of-memory handling
# if ( __STL_STATIC_TEMPLATE_DATA > 0 )
template <int __inst>
__oom_handler_type __malloc_alloc<__inst>::__oom_handler=(__oom_handler_type)0 ;
# else
__DECLARE_INSTANCE(__oom_handler_type, __malloc_alloc<0>::__oom_handler, =0);
# endif /* ( __STL_STATIC_TEMPLATE_DATA > 0 ) */
template <int __inst>
void * __malloc_alloc<__inst>::_S_oom_malloc(size_t __n)
{
__oom_handler_type __my_malloc_handler;
void * __result;
for (;;) {
__my_malloc_handler = __oom_handler;
if (0 == __my_malloc_handler) { __THROW_BAD_ALLOC; }
(*__my_malloc_handler)();
__result = malloc(__n);
if (__result) return(__result);
}
#if defined(__STL_NEED_UNREACHABLE_RETURN)
return 0;
#endif
}
template <int __inst>
void* __malloc_alloc<__inst>::_S_oom_realloc(void* __p, size_t __n)
{
__oom_handler_type __my_malloc_handler;
void* __result;
for (;;) {
__my_malloc_handler = __oom_handler;
if (0 == __my_malloc_handler) { __THROW_BAD_ALLOC; }
(*__my_malloc_handler)();
__result = realloc(__p, __n);
if (__result) return(__result);
}
#if defined(__STL_NEED_UNREACHABLE_RETURN)
return 0;
#endif
}
# ifdef __STL_DEBUG_ALLOC
template <class _Alloc>
void * __debug_alloc<_Alloc>::allocate(size_t __n) {
size_t __real_n = __n + __extra_before_chunk() + __extra_after_chunk();
__alloc_header *__result = (__alloc_header *)__allocator_type::allocate(__real_n);
memset((char*)__result, __shred_byte, __real_n*sizeof(value_type));
__result->__magic = __magic;
__result->__type_size = sizeof(value_type);
__result->_M_size = __n;
return ((char*)__result) + (long)__extra_before;
}
template <class _Alloc>
void __debug_alloc<_Alloc>::deallocate(void *__p, size_t __n) {
__alloc_header * __real_p = (__alloc_header*)((char *)__p -(long)__extra_before);
// check integrity
__stl_verbose_assert(__real_p->__magic != __deleted_magic, _StlMsg_DBA_DELETED_TWICE);
__stl_verbose_assert(__real_p->__magic == __magic, _StlMsg_DBA_NEVER_ALLOCATED);
__stl_verbose_assert(__real_p->__type_size == sizeof(value_type),
_StlMsg_DBA_TYPE_MISMATCH);
__stl_verbose_assert(__real_p->_M_size == __n, _StlMsg_DBA_SIZE_MISMATCH);
// check pads on both sides
unsigned char* __tmp;
for (__tmp= (unsigned char*)(__real_p+1); __tmp < (unsigned char*)__p; __tmp++)
__stl_verbose_assert(*__tmp==__shred_byte, _StlMsg_DBA_UNDERRUN);
size_t __real_n= __n + __extra_before_chunk() + __extra_after_chunk();
for (__tmp= ((unsigned char*)__p)+__n*sizeof(value_type);
__tmp < ((unsigned char*)__real_p)+__real_n ; __tmp++)
__stl_verbose_assert(*__tmp==__shred_byte, _StlMsg_DBA_OVERRUN);
// that may be unfortunate, just in case
__real_p->__magic=__deleted_magic;
memset((char*)__p, __shred_byte, __n*sizeof(value_type));
__allocator_type::deallocate(__real_p, __real_n);
}
# if 0
template <class _Alloc>
void *
__debug_alloc<_Alloc>::reallocate(void *__p, size_t __old_sz, size_t __new_sz) {
__alloc_header * __real_p = (__alloc_header*)((char *)__p - (long)__extra_before);
size_t __extra = __extra_before_chunk() + __extra_after_chunk();
__stl_verbose_assert(__real_p->__magic != __deleted_magic, _StlMsg_DBA_DELETED_TWICE);
__stl_verbose_assert(__real_p->__magic == __magic, _StlMsg_DBA_NEVER_ALLOCATED);
__stl_verbose_assert(__real_p->__type_size == sizeof(value_type),
_StlMsg_DBA_TYPE_MISMATCH);
__stl_verbose_assert(__real_p->_M_size == __old_sz, _StlMsg_DBA_SIZE_MISMATCH);
__real_p = (__alloc_header*)__allocator_type::reallocate(__real_p, __old_sz + __extra,
__new_sz + __extra);
__real_p->_M_size = __new_sz;
return ((char*)__real_p) + (long)__extra_before;
}
# endif
#endif
/* We allocate memory in large chunks in order to avoid fragmenting */
/* the malloc heap too much. */
/* We assume that size is properly aligned. */
/* We hold the allocation lock. */
template <bool __threads, int __inst>
char*
__node_alloc<__threads, __inst>::_S_chunk_alloc(size_t _p_size,
int& __nobjs)
{
char* __result;
size_t __total_bytes = _p_size * __nobjs;
size_t __bytes_left = _S_end_free - _S_start_free;
if (__bytes_left >= __total_bytes) {
__result = _S_start_free;
_S_start_free += __total_bytes;
return(__result);
} else if (__bytes_left >= _p_size) {
__nobjs = (int)(__bytes_left/_p_size);
__total_bytes = _p_size * __nobjs;
__result = _S_start_free;
_S_start_free += __total_bytes;
return(__result);
} else {
size_t __bytes_to_get =
2 * __total_bytes + _S_round_up(_S_heap_size >> 4);
// Try to make use of the left-over piece.
if (__bytes_left > 0) {
_Obj* __STL_VOLATILE* __my_free_list =
_S_free_list + _S_freelist_index(__bytes_left);
((_Obj*)_S_start_free) -> _M_free_list_link = *__my_free_list;
*__my_free_list = (_Obj*)_S_start_free;
}
_S_start_free = (char*)__STL_CHUNK_MALLOC(__bytes_to_get);
if (0 == _S_start_free) {
size_t __i;
_Obj* __STL_VOLATILE* __my_free_list;
_Obj* __p;
// Try to make do with what we have. That can't
// hurt. We do not try smaller requests, since that tends
// to result in disaster on multi-process machines.
for (__i = _p_size; __i <= (size_t)_MAX_BYTES; __i += (size_t)_ALIGN) {
__my_free_list = _S_free_list + _S_freelist_index(__i);
__p = *__my_free_list;
if (0 != __p) {
*__my_free_list = __p -> _M_free_list_link;
_S_start_free = (char*)__p;
_S_end_free = _S_start_free + __i;
return(_S_chunk_alloc(_p_size, __nobjs));
// Any leftover piece will eventually make it to the
// right free list.
}
}
_S_end_free = 0; // In case of exception.
_S_start_free = (char*)__STL_CHUNK_MALLOC(__bytes_to_get);
/*
(char*)malloc_alloc::allocate(__bytes_to_get);
*/
// This should either throw an
// exception or remedy the situation. Thus we assume it
// succeeded.
}
_S_heap_size += __bytes_to_get;
_S_end_free = _S_start_free + __bytes_to_get;
return(_S_chunk_alloc(_p_size, __nobjs));
}
}
/* Returns an object of size __n, and optionally adds to size __n free list.*/
/* We assume that __n is properly aligned. */
/* We hold the allocation lock. */
template <bool __threads, int __inst>
void*
__node_alloc<__threads, __inst>::_S_refill(size_t __n)
{
int __nobjs = 20;
__n = _S_round_up(__n);
char* __chunk = _S_chunk_alloc(__n, __nobjs);
_Obj* __STL_VOLATILE* __my_free_list;
_Obj* __result;
_Obj* __current_obj;
_Obj* __next_obj;
int __i;
if (1 == __nobjs) return(__chunk);
__my_free_list = _S_free_list + _S_freelist_index(__n);
/* Build free list in chunk */
__result = (_Obj*)__chunk;
*__my_free_list = __next_obj = (_Obj*)(__chunk + __n);
for (__i = 1; ; __i++) {
__current_obj = __next_obj;
__next_obj = (_Obj*)((char*)__next_obj + __n);
if (__nobjs - 1 == __i) {
__current_obj -> _M_free_list_link = 0;
break;
} else {
__current_obj -> _M_free_list_link = __next_obj;
}
}
return(__result);
}
# if 0
template <bool threads, int inst>
void*
__node_alloc<threads, inst>::reallocate(void* __p,
size_t __old_sz,
size_t __new_sz)
{
void* __result;
size_t __copy_sz;
if (__old_sz > (size_t) _MAX_BYTES && __new_sz > (size_t) _MAX_BYTES) {
return(realloc(__p, __new_sz));
}
if (_S_round_up(__old_sz) == _S_round_up(__new_sz)) return(__p);
__result = allocate(__new_sz);
__copy_sz = __new_sz > __old_sz? __old_sz : __new_sz;
memcpy(__result, __p, __copy_sz);
deallocate(__p, __old_sz);
return(__result);
}
# endif
// those should have only one instance. Currently, if we not rebuild the std library,
// they are only being instantiated in the executable.
# if defined (__BUILDING_STLPORT_DLL) || ! defined (__STLPORT_DLL)
# if ( __STL_STATIC_TEMPLATE_DATA > 0 )
#ifdef __STL_THREADS
template <bool __threads, int __inst>
_STL_mutex_base
__node_alloc<__threads, __inst>::_S_node_allocator_lock __STL_MUTEX_INITIALIZER;
#endif
template <bool __threads, int __inst>
char *__node_alloc<__threads, __inst>::_S_start_free = 0;
template <bool __threads, int __inst>
char *__node_alloc<__threads, __inst>::_S_end_free = 0;
template <bool __threads, int __inst>
size_t __node_alloc<__threads, __inst>::_S_heap_size = 0;
template <bool __threads, int __inst>
_Node_alloc_obj * __STL_VOLATILE
__node_alloc<__threads, __inst>::_S_free_list[_NFREELISTS]
= {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
// The 16 zeros are necessary to make version 4.1 of the SunPro
// compiler happy. Otherwise it appears to allocate too little
// space for the array.
# else /* ( __STL_STATIC_TEMPLATE_DATA > 0 ) */
__DECLARE_INSTANCE(char *, __single_client_alloc::_S_start_free,=0);
__DECLARE_INSTANCE(char *, __single_client_alloc::_S_end_free,=0);
__DECLARE_INSTANCE(size_t, __single_client_alloc::_S_heap_size,=0);
__DECLARE_INSTANCE(_Node_alloc_obj * __STL_VOLATILE,
__single_client_alloc::_S_free_list[_NFREELISTS],
={0});
__DECLARE_INSTANCE(char *, __multithreaded_alloc::_S_start_free,=0);
__DECLARE_INSTANCE(char *, __multithreaded_alloc::_S_end_free,=0);
__DECLARE_INSTANCE(size_t, __multithreaded_alloc::_S_heap_size,=0);
__DECLARE_INSTANCE(_Node_alloc_obj * __STL_VOLATILE,
__multithreaded_alloc::_S_free_list[_NFREELISTS],
={0});
# ifdef __STL_THREADS
__DECLARE_INSTANCE(_STL_mutex_base,
__single_client_alloc::_S_node_allocator_lock,
__STL_MUTEX_INITIALIZER);
__DECLARE_INSTANCE(_STL_mutex_base,
__multithreaded_alloc::_S_node_allocator_lock,
__STL_MUTEX_INITIALIZER);
# endif
# endif /* __STL_STATIC_TEMPLATE_DATA */
# endif /* __STLPORT_INSTANTIATE */
__STL_END_NAMESPACE
#endif /* __STL_ALLOC_C */
// Local Variables:
// mode:C++
// End:
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