| // Short-string-optimized versatile string base -*- C++ -*- |
| |
| // Copyright (C) 2005-2020 Free Software Foundation, Inc. |
| // |
| // This file is part of the GNU ISO C++ Library. This library is free |
| // software; you can redistribute it and/or modify it under the |
| // terms of the GNU General Public License as published by the |
| // Free Software Foundation; either version 3, or (at your option) |
| // any later version. |
| |
| // This library is distributed in the hope that it will be useful, |
| // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| // GNU General Public License for more details. |
| |
| // Under Section 7 of GPL version 3, you are granted additional |
| // permissions described in the GCC Runtime Library Exception, version |
| // 3.1, as published by the Free Software Foundation. |
| |
| // You should have received a copy of the GNU General Public License and |
| // a copy of the GCC Runtime Library Exception along with this program; |
| // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
| // <http://www.gnu.org/licenses/>. |
| |
| /** @file ext/sso_string_base.h |
| * This is an internal header file, included by other library headers. |
| * Do not attempt to use it directly. @headername{ext/vstring.h} |
| */ |
| |
| #ifndef _SSO_STRING_BASE_H |
| #define _SSO_STRING_BASE_H 1 |
| |
| namespace __gnu_cxx _GLIBCXX_VISIBILITY(default) |
| { |
| _GLIBCXX_BEGIN_NAMESPACE_VERSION |
| |
| template<typename _CharT, typename _Traits, typename _Alloc> |
| class __sso_string_base |
| : protected __vstring_utility<_CharT, _Traits, _Alloc> |
| { |
| public: |
| typedef _Traits traits_type; |
| typedef typename _Traits::char_type value_type; |
| |
| typedef __vstring_utility<_CharT, _Traits, _Alloc> _Util_Base; |
| typedef typename _Util_Base::_CharT_alloc_type _CharT_alloc_type; |
| typedef typename _CharT_alloc_type::size_type size_type; |
| |
| private: |
| // Data Members: |
| typename _Util_Base::template _Alloc_hider<_CharT_alloc_type> |
| _M_dataplus; |
| size_type _M_string_length; |
| |
| enum { _S_local_capacity = 15 }; |
| |
| union |
| { |
| _CharT _M_local_data[_S_local_capacity + 1]; |
| size_type _M_allocated_capacity; |
| }; |
| |
| void |
| _M_data(_CharT* __p) |
| { _M_dataplus._M_p = __p; } |
| |
| void |
| _M_length(size_type __length) |
| { _M_string_length = __length; } |
| |
| void |
| _M_capacity(size_type __capacity) |
| { _M_allocated_capacity = __capacity; } |
| |
| bool |
| _M_is_local() const |
| { return _M_data() == _M_local_data; } |
| |
| // Create & Destroy |
| _CharT* |
| _M_create(size_type&, size_type); |
| |
| void |
| _M_dispose() |
| { |
| if (!_M_is_local()) |
| _M_destroy(_M_allocated_capacity); |
| } |
| |
| void |
| _M_destroy(size_type __size) throw() |
| { _M_get_allocator().deallocate(_M_data(), __size + 1); } |
| |
| // _M_construct_aux is used to implement the 21.3.1 para 15 which |
| // requires special behaviour if _InIterator is an integral type |
| template<typename _InIterator> |
| void |
| _M_construct_aux(_InIterator __beg, _InIterator __end, |
| std::__false_type) |
| { |
| typedef typename std::iterator_traits<_InIterator>::iterator_category |
| _Tag; |
| _M_construct(__beg, __end, _Tag()); |
| } |
| |
| // _GLIBCXX_RESOLVE_LIB_DEFECTS |
| // 438. Ambiguity in the "do the right thing" clause |
| template<typename _Integer> |
| void |
| _M_construct_aux(_Integer __beg, _Integer __end, std::__true_type) |
| { _M_construct_aux_2(static_cast<size_type>(__beg), __end); } |
| |
| void |
| _M_construct_aux_2(size_type __req, _CharT __c) |
| { _M_construct(__req, __c); } |
| |
| template<typename _InIterator> |
| void |
| _M_construct(_InIterator __beg, _InIterator __end) |
| { |
| typedef typename std::__is_integer<_InIterator>::__type _Integral; |
| _M_construct_aux(__beg, __end, _Integral()); |
| } |
| |
| // For Input Iterators, used in istreambuf_iterators, etc. |
| template<typename _InIterator> |
| void |
| _M_construct(_InIterator __beg, _InIterator __end, |
| std::input_iterator_tag); |
| |
| // For forward_iterators up to random_access_iterators, used for |
| // string::iterator, _CharT*, etc. |
| template<typename _FwdIterator> |
| void |
| _M_construct(_FwdIterator __beg, _FwdIterator __end, |
| std::forward_iterator_tag); |
| |
| void |
| _M_construct(size_type __req, _CharT __c); |
| |
| public: |
| size_type |
| _M_max_size() const |
| { |
| typedef __alloc_traits<_CharT_alloc_type> _ATraits; |
| return (_ATraits::max_size(_M_get_allocator()) - 1) / 2; |
| } |
| |
| _CharT* |
| _M_data() const |
| { return _M_dataplus._M_p; } |
| |
| size_type |
| _M_length() const |
| { return _M_string_length; } |
| |
| size_type |
| _M_capacity() const |
| { |
| return _M_is_local() ? size_type(_S_local_capacity) |
| : _M_allocated_capacity; |
| } |
| |
| bool |
| _M_is_shared() const |
| { return false; } |
| |
| void |
| _M_set_leaked() { } |
| |
| void |
| _M_leak() { } |
| |
| void |
| _M_set_length(size_type __n) |
| { |
| _M_length(__n); |
| traits_type::assign(_M_data()[__n], _CharT()); |
| } |
| |
| __sso_string_base() |
| : _M_dataplus(_M_local_data) |
| { _M_set_length(0); } |
| |
| __sso_string_base(const _Alloc& __a); |
| |
| __sso_string_base(const __sso_string_base& __rcs); |
| |
| #if __cplusplus >= 201103L |
| __sso_string_base(__sso_string_base&& __rcs); |
| #endif |
| |
| __sso_string_base(size_type __n, _CharT __c, const _Alloc& __a); |
| |
| template<typename _InputIterator> |
| __sso_string_base(_InputIterator __beg, _InputIterator __end, |
| const _Alloc& __a); |
| |
| ~__sso_string_base() |
| { _M_dispose(); } |
| |
| _CharT_alloc_type& |
| _M_get_allocator() |
| { return _M_dataplus; } |
| |
| const _CharT_alloc_type& |
| _M_get_allocator() const |
| { return _M_dataplus; } |
| |
| void |
| _M_swap(__sso_string_base& __rcs); |
| |
| void |
| _M_assign(const __sso_string_base& __rcs); |
| |
| void |
| _M_reserve(size_type __res); |
| |
| void |
| _M_mutate(size_type __pos, size_type __len1, const _CharT* __s, |
| size_type __len2); |
| |
| void |
| _M_erase(size_type __pos, size_type __n); |
| |
| void |
| _M_clear() |
| { _M_set_length(0); } |
| |
| bool |
| _M_compare(const __sso_string_base&) const |
| { return false; } |
| }; |
| |
| template<typename _CharT, typename _Traits, typename _Alloc> |
| void |
| __sso_string_base<_CharT, _Traits, _Alloc>:: |
| _M_swap(__sso_string_base& __rcs) |
| { |
| if (this == &__rcs) |
| return; |
| |
| // _GLIBCXX_RESOLVE_LIB_DEFECTS |
| // 431. Swapping containers with unequal allocators. |
| std::__alloc_swap<_CharT_alloc_type>::_S_do_it(_M_get_allocator(), |
| __rcs._M_get_allocator()); |
| |
| if (_M_is_local()) |
| if (__rcs._M_is_local()) |
| { |
| if (_M_length() && __rcs._M_length()) |
| { |
| _CharT __tmp_data[_S_local_capacity + 1]; |
| traits_type::copy(__tmp_data, __rcs._M_local_data, |
| _S_local_capacity + 1); |
| traits_type::copy(__rcs._M_local_data, _M_local_data, |
| _S_local_capacity + 1); |
| traits_type::copy(_M_local_data, __tmp_data, |
| _S_local_capacity + 1); |
| } |
| else if (__rcs._M_length()) |
| { |
| traits_type::copy(_M_local_data, __rcs._M_local_data, |
| _S_local_capacity + 1); |
| _M_length(__rcs._M_length()); |
| __rcs._M_set_length(0); |
| return; |
| } |
| else if (_M_length()) |
| { |
| traits_type::copy(__rcs._M_local_data, _M_local_data, |
| _S_local_capacity + 1); |
| __rcs._M_length(_M_length()); |
| _M_set_length(0); |
| return; |
| } |
| } |
| else |
| { |
| const size_type __tmp_capacity = __rcs._M_allocated_capacity; |
| traits_type::copy(__rcs._M_local_data, _M_local_data, |
| _S_local_capacity + 1); |
| _M_data(__rcs._M_data()); |
| __rcs._M_data(__rcs._M_local_data); |
| _M_capacity(__tmp_capacity); |
| } |
| else |
| { |
| const size_type __tmp_capacity = _M_allocated_capacity; |
| if (__rcs._M_is_local()) |
| { |
| traits_type::copy(_M_local_data, __rcs._M_local_data, |
| _S_local_capacity + 1); |
| __rcs._M_data(_M_data()); |
| _M_data(_M_local_data); |
| } |
| else |
| { |
| _CharT* __tmp_ptr = _M_data(); |
| _M_data(__rcs._M_data()); |
| __rcs._M_data(__tmp_ptr); |
| _M_capacity(__rcs._M_allocated_capacity); |
| } |
| __rcs._M_capacity(__tmp_capacity); |
| } |
| |
| const size_type __tmp_length = _M_length(); |
| _M_length(__rcs._M_length()); |
| __rcs._M_length(__tmp_length); |
| } |
| |
| template<typename _CharT, typename _Traits, typename _Alloc> |
| _CharT* |
| __sso_string_base<_CharT, _Traits, _Alloc>:: |
| _M_create(size_type& __capacity, size_type __old_capacity) |
| { |
| // _GLIBCXX_RESOLVE_LIB_DEFECTS |
| // 83. String::npos vs. string::max_size() |
| if (__capacity > _M_max_size()) |
| std::__throw_length_error(__N("__sso_string_base::_M_create")); |
| |
| // The below implements an exponential growth policy, necessary to |
| // meet amortized linear time requirements of the library: see |
| // http://gcc.gnu.org/ml/libstdc++/2001-07/msg00085.html. |
| if (__capacity > __old_capacity && __capacity < 2 * __old_capacity) |
| { |
| __capacity = 2 * __old_capacity; |
| // Never allocate a string bigger than max_size. |
| if (__capacity > _M_max_size()) |
| __capacity = _M_max_size(); |
| } |
| |
| // NB: Need an array of char_type[__capacity], plus a terminating |
| // null char_type() element. |
| return _M_get_allocator().allocate(__capacity + 1); |
| } |
| |
| template<typename _CharT, typename _Traits, typename _Alloc> |
| __sso_string_base<_CharT, _Traits, _Alloc>:: |
| __sso_string_base(const _Alloc& __a) |
| : _M_dataplus(__a, _M_local_data) |
| { _M_set_length(0); } |
| |
| template<typename _CharT, typename _Traits, typename _Alloc> |
| __sso_string_base<_CharT, _Traits, _Alloc>:: |
| __sso_string_base(const __sso_string_base& __rcs) |
| : _M_dataplus(__rcs._M_get_allocator(), _M_local_data) |
| { _M_construct(__rcs._M_data(), __rcs._M_data() + __rcs._M_length()); } |
| |
| #if __cplusplus >= 201103L |
| template<typename _CharT, typename _Traits, typename _Alloc> |
| __sso_string_base<_CharT, _Traits, _Alloc>:: |
| __sso_string_base(__sso_string_base&& __rcs) |
| : _M_dataplus(__rcs._M_get_allocator(), _M_local_data) |
| { |
| if (__rcs._M_is_local()) |
| { |
| if (__rcs._M_length()) |
| traits_type::copy(_M_local_data, __rcs._M_local_data, |
| _S_local_capacity + 1); |
| } |
| else |
| { |
| _M_data(__rcs._M_data()); |
| _M_capacity(__rcs._M_allocated_capacity); |
| } |
| |
| _M_set_length(__rcs._M_length()); |
| __rcs._M_data(__rcs._M_local_data); |
| __rcs._M_set_length(0); |
| } |
| #endif |
| |
| template<typename _CharT, typename _Traits, typename _Alloc> |
| __sso_string_base<_CharT, _Traits, _Alloc>:: |
| __sso_string_base(size_type __n, _CharT __c, const _Alloc& __a) |
| : _M_dataplus(__a, _M_local_data) |
| { _M_construct(__n, __c); } |
| |
| template<typename _CharT, typename _Traits, typename _Alloc> |
| template<typename _InputIterator> |
| __sso_string_base<_CharT, _Traits, _Alloc>:: |
| __sso_string_base(_InputIterator __beg, _InputIterator __end, |
| const _Alloc& __a) |
| : _M_dataplus(__a, _M_local_data) |
| { _M_construct(__beg, __end); } |
| |
| // NB: This is the special case for Input Iterators, used in |
| // istreambuf_iterators, etc. |
| // Input Iterators have a cost structure very different from |
| // pointers, calling for a different coding style. |
| template<typename _CharT, typename _Traits, typename _Alloc> |
| template<typename _InIterator> |
| void |
| __sso_string_base<_CharT, _Traits, _Alloc>:: |
| _M_construct(_InIterator __beg, _InIterator __end, |
| std::input_iterator_tag) |
| { |
| size_type __len = 0; |
| size_type __capacity = size_type(_S_local_capacity); |
| |
| while (__beg != __end && __len < __capacity) |
| { |
| _M_data()[__len++] = *__beg; |
| ++__beg; |
| } |
| |
| __try |
| { |
| while (__beg != __end) |
| { |
| if (__len == __capacity) |
| { |
| // Allocate more space. |
| __capacity = __len + 1; |
| _CharT* __another = _M_create(__capacity, __len); |
| this->_S_copy(__another, _M_data(), __len); |
| _M_dispose(); |
| _M_data(__another); |
| _M_capacity(__capacity); |
| } |
| _M_data()[__len++] = *__beg; |
| ++__beg; |
| } |
| } |
| __catch(...) |
| { |
| _M_dispose(); |
| __throw_exception_again; |
| } |
| |
| _M_set_length(__len); |
| } |
| |
| template<typename _CharT, typename _Traits, typename _Alloc> |
| template<typename _InIterator> |
| void |
| __sso_string_base<_CharT, _Traits, _Alloc>:: |
| _M_construct(_InIterator __beg, _InIterator __end, |
| std::forward_iterator_tag) |
| { |
| // NB: Not required, but considered best practice. |
| if (__is_null_pointer(__beg) && __beg != __end) |
| std::__throw_logic_error(__N("__sso_string_base::" |
| "_M_construct null not valid")); |
| |
| size_type __dnew = static_cast<size_type>(std::distance(__beg, __end)); |
| |
| if (__dnew > size_type(_S_local_capacity)) |
| { |
| _M_data(_M_create(__dnew, size_type(0))); |
| _M_capacity(__dnew); |
| } |
| |
| // Check for out_of_range and length_error exceptions. |
| __try |
| { this->_S_copy_chars(_M_data(), __beg, __end); } |
| __catch(...) |
| { |
| _M_dispose(); |
| __throw_exception_again; |
| } |
| |
| _M_set_length(__dnew); |
| } |
| |
| template<typename _CharT, typename _Traits, typename _Alloc> |
| void |
| __sso_string_base<_CharT, _Traits, _Alloc>:: |
| _M_construct(size_type __n, _CharT __c) |
| { |
| if (__n > size_type(_S_local_capacity)) |
| { |
| _M_data(_M_create(__n, size_type(0))); |
| _M_capacity(__n); |
| } |
| |
| if (__n) |
| this->_S_assign(_M_data(), __n, __c); |
| |
| _M_set_length(__n); |
| } |
| |
| template<typename _CharT, typename _Traits, typename _Alloc> |
| void |
| __sso_string_base<_CharT, _Traits, _Alloc>:: |
| _M_assign(const __sso_string_base& __rcs) |
| { |
| if (this != &__rcs) |
| { |
| const size_type __rsize = __rcs._M_length(); |
| const size_type __capacity = _M_capacity(); |
| |
| if (__rsize > __capacity) |
| { |
| size_type __new_capacity = __rsize; |
| _CharT* __tmp = _M_create(__new_capacity, __capacity); |
| _M_dispose(); |
| _M_data(__tmp); |
| _M_capacity(__new_capacity); |
| } |
| |
| if (__rsize) |
| this->_S_copy(_M_data(), __rcs._M_data(), __rsize); |
| |
| _M_set_length(__rsize); |
| } |
| } |
| |
| template<typename _CharT, typename _Traits, typename _Alloc> |
| void |
| __sso_string_base<_CharT, _Traits, _Alloc>:: |
| _M_reserve(size_type __res) |
| { |
| // Make sure we don't shrink below the current size. |
| if (__res < _M_length()) |
| __res = _M_length(); |
| |
| const size_type __capacity = _M_capacity(); |
| if (__res != __capacity) |
| { |
| if (__res > __capacity |
| || __res > size_type(_S_local_capacity)) |
| { |
| _CharT* __tmp = _M_create(__res, __capacity); |
| this->_S_copy(__tmp, _M_data(), _M_length() + 1); |
| _M_dispose(); |
| _M_data(__tmp); |
| _M_capacity(__res); |
| } |
| else if (!_M_is_local()) |
| { |
| this->_S_copy(_M_local_data, _M_data(), _M_length() + 1); |
| _M_destroy(__capacity); |
| _M_data(_M_local_data); |
| } |
| } |
| } |
| |
| template<typename _CharT, typename _Traits, typename _Alloc> |
| void |
| __sso_string_base<_CharT, _Traits, _Alloc>:: |
| _M_mutate(size_type __pos, size_type __len1, const _CharT* __s, |
| size_type __len2) |
| { |
| const size_type __how_much = _M_length() - __pos - __len1; |
| |
| size_type __new_capacity = _M_length() + __len2 - __len1; |
| _CharT* __r = _M_create(__new_capacity, _M_capacity()); |
| |
| if (__pos) |
| this->_S_copy(__r, _M_data(), __pos); |
| if (__s && __len2) |
| this->_S_copy(__r + __pos, __s, __len2); |
| if (__how_much) |
| this->_S_copy(__r + __pos + __len2, |
| _M_data() + __pos + __len1, __how_much); |
| |
| _M_dispose(); |
| _M_data(__r); |
| _M_capacity(__new_capacity); |
| } |
| |
| template<typename _CharT, typename _Traits, typename _Alloc> |
| void |
| __sso_string_base<_CharT, _Traits, _Alloc>:: |
| _M_erase(size_type __pos, size_type __n) |
| { |
| const size_type __how_much = _M_length() - __pos - __n; |
| |
| if (__how_much && __n) |
| this->_S_move(_M_data() + __pos, _M_data() + __pos + __n, __how_much); |
| |
| _M_set_length(_M_length() - __n); |
| } |
| |
| _GLIBCXX_END_NAMESPACE_VERSION |
| } // namespace |
| |
| #endif /* _SSO_STRING_BASE_H */ |