📄 11603.cc
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// Copyright (C) 2003, 2004 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 2, 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.// You should have received a copy of the GNU General Public License along// with this library; see the file COPYING. If not, write to the Free// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,// USA.// 27.8.1.4 Overridden virtual functions#include <fstream>#include <locale>#include <testsuite_hooks.h>template <typename InternT, typename StateT = std::mbstate_t>class checksumcvt : public std::codecvt<InternT, char, StateT>{ typedef std::codecvt<InternT, char, StateT> Base; static const std::size_t width = sizeof(InternT) + 1;public: typedef InternT intern_type; typedef char extern_type; explicit checksumcvt(std::size_t refs = 0) : Base(refs) { }protected: virtual std::codecvt_base::result do_out(StateT&, const intern_type* from, const intern_type* from_end, const intern_type*& from_next, extern_type* to, extern_type* to_end, extern_type*& to_next) const { size_t len = std::min(static_cast<size_t>(from_end - from), static_cast<size_t>(to_end - to) / width); while (len--) { const char* p = reinterpret_cast<const char*>(from); unsigned char checksum = 0; for (std::size_t i = 0; i < sizeof(intern_type); ++i) { *to++ = p[i]; checksum ^= static_cast<unsigned char>(p[i]); } *to++ = checksum; ++from; } from_next = from; to_next = to; return from_next == from_end ? std::codecvt_base::ok : std::codecvt_base::partial; } virtual std::codecvt_base::result do_unshift(StateT&, extern_type* to, extern_type*, extern_type*& to_next) const { to_next = to; return std::codecvt_base::ok; } virtual std::codecvt_base::result do_in(StateT&, const extern_type* from, const extern_type* from_end, const extern_type*& from_next, intern_type* to, intern_type* to_end, intern_type*& to_next) const { size_t len = std::min(static_cast<size_t>(to_end - to), static_cast<size_t>(from_end - from) / width); while (len) { const char* f = from; intern_type tmp; char* p = reinterpret_cast<char*>(&tmp); unsigned char checksum = 0; for (std::size_t i = 0; i < sizeof(intern_type); ++i) { p[i] = *f; checksum ^= static_cast<unsigned char>(*f++); } if (*f++ != checksum) break; from = f; *to++ = tmp; len--; } from_next = from; to_next = to; return len ? std::codecvt_base::error : (from_next == from_end ? std::codecvt_base::ok : std::codecvt_base::partial); } virtual int do_encoding() const throw() { return width; } virtual int do_length(const StateT&, const extern_type* from, const extern_type* end, size_t max) const { size_t len = std::min(max, static_cast<size_t>(end - from) / width); int ret = 0; while (len--) { unsigned char checksum = 0; for (std::size_t i = 0; i < sizeof(intern_type); ++i) { checksum ^= static_cast<unsigned char>(*from++); } if (*from++ != checksum) break; ret++; } return ret; } virtual int do_max_length() const throw() { return width; } virtual bool do_always_noconv() const throw() { return false; }};class Buf : public std::wfilebuf{public: std::streamsize pub_showmanyc() { return showmanyc(); } std::wfilebuf::int_type pub_underflow() { return underflow(); }};// libstdc++/11603void test01(){ using namespace std; bool test __attribute__((unused)) = true; filebuf fbout; fbout.open("tmp_11603", ios_base::out); fbout.sputn("aaaab", 5); fbout.close(); locale loc(locale::classic(), new checksumcvt<wchar_t>); Buf fb; fb.pubimbue(loc); fb.open("tmp_11603", ios_base::in); VERIFY( fb.pub_showmanyc() == 1 ); try { wfilebuf::int_type ret = fb.pub_underflow(); VERIFY( ret != wfilebuf::traits_type::eof() ); fb.sbumpc(); ret = fb.pub_underflow(); VERIFY( ret == wfilebuf::traits_type::eof() ); } catch (...) { } fb.close();}int main(){ test01(); return 0;}
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