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// <syncstream> -*- C++ -*- |
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|
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// Copyright (C) 2020-2021 Free Software Foundation, Inc. |
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// |
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// This file is part of the GNU ISO C++ Library. This library is free |
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// software; you can redistribute it and/or modify it under the |
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// terms of the GNU General Public License as published by the |
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// Free Software Foundation; either version 3, or (at your option) |
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// any later version. |
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|
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// This library is distributed in the hope that it will be useful, |
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// but WITHOUT ANY WARRANTY; without even the implied warranty of |
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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// GNU General Public License for more details. |
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|
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// Under Section 7 of GPL version 3, you are granted additional |
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// permissions described in the GCC Runtime Library Exception, version |
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// 3.1, as published by the Free Software Foundation. |
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|
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// You should have received a copy of the GNU General Public License and |
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// a copy of the GCC Runtime Library Exception along with this program; |
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// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
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// <http://www.gnu.org/licenses/>. |
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|
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/** @file include/syncstream |
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* This is a Standard C++ Library header. |
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*/ |
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|
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#ifndef _GLIBCXX_SYNCSTREAM |
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#define _GLIBCXX_SYNCSTREAM 1 |
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|
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#if __cplusplus > 201703L |
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|
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#include <bits/c++config.h> |
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#if _GLIBCXX_USE_CXX11_ABI |
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|
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#define __cpp_lib_syncbuf 201803L |
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|
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#pragma GCC system_header |
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|
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#include <sstream> |
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|
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#include <bits/alloc_traits.h> |
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#include <bits/allocator.h> |
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#include <bits/functexcept.h> |
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#include <bits/functional_hash.h> |
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#include <bits/std_mutex.h> |
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|
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namespace std _GLIBCXX_VISIBILITY(default) |
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{ |
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_GLIBCXX_BEGIN_NAMESPACE_VERSION |
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|
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template<typename _CharT, typename _Traits = char_traits<_CharT>, |
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typename _Alloc = allocator<_CharT>> |
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class basic_syncbuf : public __syncbuf_base<_CharT, _Traits> |
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{ |
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public: |
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using char_type = _CharT; |
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using int_type = typename _Traits::int_type; |
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using pos_type = typename _Traits::pos_type; |
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using off_type = typename _Traits::off_type; |
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using traits_type = _Traits; |
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using allocator_type = _Alloc; |
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using streambuf_type = basic_streambuf<_CharT, _Traits>; |
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|
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basic_syncbuf() |
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: basic_syncbuf(nullptr, allocator_type{}) |
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{ } |
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|
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explicit |
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basic_syncbuf(streambuf_type* __obuf) |
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: basic_syncbuf(__obuf, allocator_type{}) |
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{ } |
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|
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basic_syncbuf(streambuf_type* __obuf, const allocator_type& __alloc) |
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: __syncbuf_base<_CharT, _Traits>(__obuf) |
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, _M_impl(__alloc) |
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, _M_mtx(__obuf) |
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{ } |
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|
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basic_syncbuf(basic_syncbuf&& __other) |
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: __syncbuf_base<_CharT, _Traits>(__other._M_wrapped) |
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, _M_impl(std::move(__other._M_impl)) |
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, _M_mtx(std::move(__other._M_mtx)) |
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{ |
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this->_M_emit_on_sync = __other._M_emit_on_sync; |
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this->_M_needs_sync = __other._M_needs_sync; |
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__other._M_wrapped = nullptr; |
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} |
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|
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~basic_syncbuf() |
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{ |
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__try |
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{ |
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emit(); |
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} |
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__catch (...) |
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{ } |
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} |
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|
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basic_syncbuf& |
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operator=(basic_syncbuf&& __other) |
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{ |
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emit(); |
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|
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_M_impl = std::move(__other._M_impl); |
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this->_M_emit_on_sync = __other._M_emit_on_sync; |
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this->_M_needs_sync = __other._M_needs_sync; |
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this->_M_wrapped = __other._M_wrapped; |
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__other._M_wrapped = nullptr; |
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_M_mtx = std::move(__other._M_mtx); |
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|
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return *this; |
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} |
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|
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void |
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swap(basic_syncbuf& __other) noexcept |
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{ |
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using _ATr = allocator_traits<_Alloc>; |
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if constexpr (!_ATr::propagate_on_container_swap::value) |
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__glibcxx_assert(get_allocator() == __other.get_allocator()); |
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|
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std::swap(_M_impl, __other._M_impl); |
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std::swap(this->_M_emit_on_sync, __other._M_emit_on_sync); |
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std::swap(this->_M_needs_sync, __other._M_needs_sync); |
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std::swap(this->_M_wrapped, __other._M_wrapped); |
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std::swap(_M_mtx, __other._M_mtx); |
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} |
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|
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bool |
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emit() |
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{ |
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if (!this->_M_wrapped) |
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return false; |
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|
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auto __s = std::move(_M_impl).str(); |
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|
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const lock_guard<__mutex> __l(_M_mtx); |
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if (auto __size = __s.size()) |
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{ |
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auto __n = this->_M_wrapped->sputn(__s.data(), __size); |
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if (__n != __size) |
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{ |
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__s.erase(0, __n); |
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_M_impl.str(std::move(__s)); |
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return false; |
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} |
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} |
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|
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if (this->_M_needs_sync) |
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{ |
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this->_M_needs_sync = false; |
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if (this->_M_wrapped->pubsync() != 0) |
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return false; |
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} |
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return true; |
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} |
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|
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streambuf_type* |
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get_wrapped() const noexcept |
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{ return this->_M_wrapped; } |
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|
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allocator_type |
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get_allocator() const noexcept |
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{ return _M_impl.get_allocator(); } |
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|
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void |
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set_emit_on_sync(bool __b) noexcept |
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{ this->_M_emit_on_sync = __b; } |
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|
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protected: |
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int |
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sync() override |
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{ |
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this->_M_needs_sync = true; |
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if (this->_M_emit_on_sync && !emit()) |
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return -1; |
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return 0; |
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} |
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|
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int_type |
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overflow(int_type __c) override |
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{ |
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int_type __eof = traits_type::eof(); |
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if (__builtin_expect(!traits_type::eq_int_type(__c, __eof), true)) |
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return _M_impl.sputc(__c); |
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return __eof; |
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} |
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|
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streamsize |
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xsputn(const char_type* __s, streamsize __n) override |
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{ return _M_impl.sputn(__s, __n); } |
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|
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private: |
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basic_stringbuf<char_type, traits_type, allocator_type> _M_impl; |
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|
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struct __mutex |
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{ |
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#if _GLIBCXX_HAS_GTHREADS |
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mutex* _M_mtx; |
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|
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__mutex(void* __t) |
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: _M_mtx(__t ? &_S_get_mutex(__t) : nullptr) |
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{ } |
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|
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void |
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swap(__mutex& __other) noexcept |
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{ std::swap(_M_mtx, __other._M_mtx); } |
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|
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void |
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lock() |
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{ |
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_M_mtx->lock(); |
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} |
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|
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void |
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unlock() |
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{ |
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_M_mtx->unlock(); |
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} |
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|
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// FIXME: This should be put in the .so |
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static mutex& |
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_S_get_mutex(void* __t) |
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{ |
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const unsigned char __mask = 0xf; |
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static mutex __m[__mask + 1]; |
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|
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auto __key = _Hash_impl::hash(__t) & __mask; |
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return __m[__key]; |
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} |
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#else |
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__mutex(void*) { } |
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void swap(__mutex&&) noexcept { } |
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void lock() { } |
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void unlock() { } |
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#endif |
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__mutex(__mutex&&) = default; |
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__mutex& operator=(__mutex&&) = default; |
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}; |
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__mutex _M_mtx; |
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}; |
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|
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template <typename _CharT, typename _Traits = char_traits<_CharT>, |
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typename _Alloc = allocator<_CharT>> |
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class basic_osyncstream : public basic_ostream<_CharT, _Traits> |
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{ |
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using __ostream_type = basic_ostream<_CharT, _Traits>; |
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|
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public: |
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// Types: |
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using char_type = _CharT; |
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using traits_type = _Traits; |
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using allocator_type = _Alloc; |
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using int_type = typename traits_type::int_type; |
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using pos_type = typename traits_type::pos_type; |
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using off_type = typename traits_type::off_type; |
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using syncbuf_type = basic_syncbuf<_CharT, _Traits, _Alloc>; |
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using streambuf_type = typename syncbuf_type::streambuf_type; |
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|
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private: |
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syncbuf_type _M_syncbuf; |
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|
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public: |
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basic_osyncstream(streambuf_type* __buf, const allocator_type& __a) |
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: _M_syncbuf(__buf, __a) |
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{ this->init(std::__addressof(_M_syncbuf)); } |
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|
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explicit basic_osyncstream(streambuf_type* __buf) |
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: _M_syncbuf(__buf) |
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{ this->init(std::__addressof(_M_syncbuf)); } |
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|
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basic_osyncstream(basic_ostream<char_type, traits_type>& __os, |
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const allocator_type& __a) |
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: basic_osyncstream(__os.rdbuf(), __a) |
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{ this->init(std::__addressof(_M_syncbuf)); } |
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|
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explicit basic_osyncstream(basic_ostream<char_type, traits_type>& __os) |
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: basic_osyncstream(__os.rdbuf()) |
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{ this->init(std::__addressof(_M_syncbuf)); } |
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|
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basic_osyncstream(basic_osyncstream&& __rhs) noexcept |
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: __ostream_type(std::move(__rhs)), |
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_M_syncbuf(std::move(__rhs._M_syncbuf)) |
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{ __ostream_type::set_rdbuf(std::__addressof(_M_syncbuf)); } |
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|
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~basic_osyncstream() = default; |
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|
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basic_osyncstream& operator=(basic_osyncstream&&) noexcept = default; |
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|
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syncbuf_type* rdbuf() const noexcept |
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{ return const_cast<syncbuf_type*>(&_M_syncbuf); } |
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|
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streambuf_type* get_wrapped() const noexcept |
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{ return _M_syncbuf.get_wrapped(); } |
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|
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void emit() |
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{ |
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if (!_M_syncbuf.emit()) |
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this->setstate(ios_base::failbit); |
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} |
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}; |
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|
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template <class _CharT, class _Traits, class _Allocator> |
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inline void |
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swap(basic_syncbuf<_CharT, _Traits, _Allocator>& __x, |
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basic_syncbuf<_CharT, _Traits, _Allocator>& __y) noexcept |
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{ __x.swap(__y); } |
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|
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using syncbuf = basic_syncbuf<char>; |
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using wsyncbuf = basic_syncbuf<wchar_t>; |
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|
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using osyncstream = basic_osyncstream<char>; |
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using wosyncstream = basic_osyncstream<wchar_t>; |
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_GLIBCXX_END_NAMESPACE_VERSION |
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} // namespace std |
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#endif // _GLIBCXX_USE_CXX11_ABI |
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#endif // C++2a |
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#endif /* _GLIBCXX_SYNCSTREAM */ |
