system/detail/system_category_message_win32.hpp

0001 #ifndef BOOST_SYSTEM_DETAIL_SYSTEM_CATEGORY_MESSAGE_WIN32_HPP_INCLUDED
0002 #define BOOST_SYSTEM_DETAIL_SYSTEM_CATEGORY_MESSAGE_WIN32_HPP_INCLUDED
0003
0004 // Copyright Beman Dawes 2002, 2006
0005 // Copyright (c) Microsoft Corporation 2014
0006 // Copyright 2018, 2020 Peter Dimov
0007 //
0008 // Distributed under the Boost Software License, Version 1.0. (See accompanying
0009 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0010 //
0011 // See library home page at http://www.boost.org/libs/system
0012
0013 #include <boost/system/detail/snprintf.hpp>
0014 #include <boost/winapi/error_handling.hpp>
0015 #include <boost/winapi/character_code_conversion.hpp>
0016 #include <boost/winapi/local_memory.hpp>
0017 #include <boost/config.hpp>
0018 #include <cstdio>
0019
0020 //
0021
0022 namespace boost
0023 {
0024
0025 namespace system
0026 {
0027
0028 namespace detail
0029 {
0030
0031 inline char const * unknown_message_win32( int ev, char * buffer, std::size_t len )
0032 {
0033     detail::snprintf( buffer, len, "Unknown error (%d)", ev );
0034     return buffer;
0035 }
0036
0037 inline boost::winapi::UINT_ message_cp_win32()
0038 {
0039 #if defined(BOOST_SYSTEM_USE_UTF8)
0040
0041     return boost::winapi::CP_UTF8_;
0042
0043 #else
0044
0045     return boost::winapi::CP_ACP_;
0046
0047 #endif
0048 }
0049
0050 inline char const * system_category_message_win32( int ev, char * buffer, std::size_t len ) BOOST_NOEXCEPT
0051 {
0052     if( len == 0 )
0053     {
0054         return buffer;
0055     }
0056
0057     if( len == 1 )
0058     {
0059         buffer[0] = 0;
0060         return buffer;
0061     }
0062
0063     boost::winapi::UINT_ const code_page = message_cp_win32();
0064
0065     int r = 0;
0066
0067 #if !defined(BOOST_NO_ANSI_APIS)
0068
0069     if( code_page == boost::winapi::CP_ACP_ )
0070     {
0071         using namespace boost::winapi;
0072
0073         DWORD_ retval = boost::winapi::FormatMessageA(
0074             FORMAT_MESSAGE_FROM_SYSTEM_ | FORMAT_MESSAGE_IGNORE_INSERTS_,
0075             NULL,
0076             ev,
0077             MAKELANGID_( LANG_NEUTRAL_, SUBLANG_DEFAULT_ ), // Default language
0078             buffer,
0079             static_cast<DWORD_>( len ),
0080             NULL
0081         );
0082
0083         r = static_cast<int>( retval );
0084     }
0085     else
0086
0087 #endif
0088
0089     {
0090         using namespace boost::winapi;
0091
0092         wchar_t * lpMsgBuf = 0;
0093
0094         DWORD_ retval = boost::winapi::FormatMessageW(
0095             FORMAT_MESSAGE_ALLOCATE_BUFFER_ | FORMAT_MESSAGE_FROM_SYSTEM_ | FORMAT_MESSAGE_IGNORE_INSERTS_,
0096             NULL,
0097             ev,
0098             MAKELANGID_( LANG_NEUTRAL_, SUBLANG_DEFAULT_ ), // Default language
0099             (LPWSTR_) &lpMsgBuf,
0100             0,
0101             NULL
0102         );
0103
0104         if( retval != 0 )
0105         {
0106             r = boost::winapi::WideCharToMultiByte( code_page, 0, lpMsgBuf, -1, buffer, static_cast<int>( len ), NULL, NULL );
0107             boost::winapi::LocalFree( lpMsgBuf );
0108             if ( r != 0 ) --r; // exclude null terminator
0109         }
0110     }
0111
0112     if( r == 0 )
0113     {
0114         return unknown_message_win32( ev, buffer, len );
0115     }
0116
0117     while( r > 0 && ( buffer[ r-1 ] == '\n' || buffer[ r-1 ] == '\r' ) )
0118     {
0119         buffer[ --r ] = 0;
0120     }
0121
0122     if( r > 0 && buffer[ r-1 ] == '.' )
0123     {
0124         buffer[ --r ] = 0;
0125     }
0126
0127     return buffer;
0128 }
0129
0130 struct local_free
0131 {
0132     void * p_;
0133
0134     ~local_free()
0135     {
0136         boost::winapi::LocalFree( p_ );
0137     }
0138 };
0139
0140 inline std::string unknown_message_win32( int ev )
0141 {
0142     char buffer[ 38 ];
0143     return unknown_message_win32( ev, buffer, sizeof( buffer ) );
0144 }
0145
0146 inline std::string system_category_message_win32( int ev )
0147 {
0148     using namespace boost::winapi;
0149
0150     wchar_t * lpMsgBuf = 0;
0151
0152     DWORD_ retval = boost::winapi::FormatMessageW(
0153         FORMAT_MESSAGE_ALLOCATE_BUFFER_ | FORMAT_MESSAGE_FROM_SYSTEM_ | FORMAT_MESSAGE_IGNORE_INSERTS_,
0154         NULL,
0155         ev,
0156         MAKELANGID_( LANG_NEUTRAL_, SUBLANG_DEFAULT_ ), // Default language
0157         (LPWSTR_) &lpMsgBuf,
0158         0,
0159         NULL
0160     );
0161
0162     if( retval == 0 )
0163     {
0164         return unknown_message_win32( ev );
0165     }
0166
0167     local_free lf_ = { lpMsgBuf };
0168     (void)lf_;
0169
0170     UINT_ const code_page = message_cp_win32();
0171
0172     int r = boost::winapi::WideCharToMultiByte( code_page, 0, lpMsgBuf, -1, 0, 0, NULL, NULL );
0173
0174     if( r == 0 )
0175     {
0176         return unknown_message_win32( ev );
0177     }
0178
0179     std::string buffer( r, char() );
0180
0181     r = boost::winapi::WideCharToMultiByte( code_page, 0, lpMsgBuf, -1, &buffer[0], r, NULL, NULL );
0182
0183     if( r == 0 )
0184     {
0185         return unknown_message_win32( ev );
0186     }
0187
0188     --r; // exclude null terminator
0189
0190     while( r > 0 && ( buffer[ r-1 ] == '\n' || buffer[ r-1 ] == '\r' ) )
0191     {
0192         --r;
0193     }
0194
0195     if( r > 0 && buffer[ r-1 ] == '.' )
0196     {
0197         --r;
0198     }
0199
0200     buffer.resize( r );
0201
0202     return buffer;
0203 }
0204
0205 } // namespace detail
0206
0207 } // namespace system
0208
0209 } // namespace boost
0210
0211 #endif // #ifndef BOOST_SYSTEM_DETAIL_SYSTEM_CATEGORY_MESSAGE_WIN32_HPP_INCLUDED