EIC code displayed by LXR master/​include/​boost/​process/​v2/​detail/​impl/​utf8.ipp	Source navigation Diff markup Identifier search General search
	Version: master test Revert   Change

File indexing completed on 2025-01-18 09:50:09

 // Copyright (c) 2022 Klemens D. Morgenstern
 //
 // Distributed under the Boost Software License, Version 1.0. (See accompanying
 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
 #ifndef BOOST_PROCESS_V2_DETAIL_IMPL_UTF8_HPP
 #define BOOST_PROCESS_V2_DETAIL_IMPL_UTF8_HPP
 
 #include <boost/process/v2/detail/utf8.hpp>
 #include <boost/process/v2/detail/config.hpp>
 #include <boost/process/v2/detail/last_error.hpp>
 #include <boost/process/v2/error.hpp>
 
 #if defined(BOOST_PROCESS_V2_WINDOWS)
 #include <Windows.h>
 #endif
 
 BOOST_PROCESS_V2_BEGIN_NAMESPACE
 
 namespace detail
 {
 
 #if defined(BOOST_PROCESS_V2_WINDOWS)
 
 inline void handle_error(error_code & ec)
 {
     const auto err = ::GetLastError();
     switch (err)
     {
     case ERROR_INSUFFICIENT_BUFFER:
         BOOST_PROCESS_V2_ASSIGN_EC(ec, error::insufficient_buffer, error::utf8_category)
         break;
     case ERROR_NO_UNICODE_TRANSLATION:
         BOOST_PROCESS_V2_ASSIGN_EC(ec, error::invalid_character, error::utf8_category)
         break;
     default:
         BOOST_PROCESS_V2_ASSIGN_EC(ec, err, system_category())
     }
 }
 
 std::size_t size_as_utf8(const wchar_t * in, std::size_t size, error_code & ec)
 {
     auto res = WideCharToMultiByte(
                           CP_UTF8,                // CodePage,
                           0,                      // dwFlags,
                           in,                     // lpWideCharStr,
                           static_cast<int>(size), // cchWideChar,
                           nullptr,                // lpMultiByteStr,
                           0,                      // cbMultiByte,
                           nullptr,                // lpDefaultChar,
                           FALSE);                 // lpUsedDefaultChar
     
     if (res == 0u)
         handle_error(ec);
     return static_cast<std::size_t>(res);
 }
 
 std::size_t size_as_wide(const char * in, std::size_t size, error_code & ec)
 {
     auto res = ::MultiByteToWideChar(
                           CP_UTF8,                // CodePage
                           0,                      // dwFlags
                           in,                     // lpMultiByteStr
                           static_cast<int>(size), // cbMultiByte
                           nullptr,                // lpWideCharStr
                           0);                     // cchWideChar
     if (res == 0u)
         handle_error(ec);
 
     return static_cast<std::size_t>(res);
 }
 
 std::size_t convert_to_utf8(const wchar_t *in, std::size_t size,  char * out, 
                             std::size_t max_size, error_code & ec)
 {
     auto res = ::WideCharToMultiByte(
                     CP_UTF8,                    // CodePage
                     0,                          // dwFlags
                     in,                         // lpWideCharStr
                     static_cast<int>(size),     // cchWideChar
                     out,                        // lpMultiByteStr
                     static_cast<int>(max_size), // cbMultiByte
                     nullptr,                    // lpDefaultChar
                     FALSE);                     // lpUsedDefaultChar
     if (res == 0u)
         handle_error(ec);
 
     return static_cast<std::size_t>(res);
 }
 
 std::size_t convert_to_wide(const char *in, std::size_t size,  wchar_t * out, 
                             std::size_t max_size, error_code & ec)
 {
     auto res = ::MultiByteToWideChar(
                           CP_UTF8,                     // CodePage
                           0,                           // dwFlags
                           in,                          // lpMultiByteStr
                           static_cast<int>(size),      // cbMultiByte
                           out,                         // lpWideCharStr
                           static_cast<int>(max_size)); // cchWideChar
     if (res == 0u)
         handle_error(ec);
 
     return static_cast<std::size_t>(res);
 }
 
 #else
 
 
 template<std::size_t s>
 inline int get_cont_octet_out_count_impl(wchar_t word) {
     if (word < 0x80) {
         return 0;
     }
     if (word < 0x800) {
         return 1;
     }
     return 2;
 }
 
 template<>
 inline int get_cont_octet_out_count_impl<4>(wchar_t word) {
     if (word < 0x80) {
         return 0;
     }
     if (word < 0x800) {
         return 1;
     }
 
     // Note that the following code will generate warnings on some platforms
     // where wchar_t is defined as UCS2.  The warnings are superfluous as the
     // specialization is never instantiated with such compilers, but this
     // can cause problems if warnings are being treated as errors, so we guard
     // against that. Including <boost/detail/utf8_codecvt_facet.hpp> as we do
     // should be enough to get WCHAR_MAX defined.
 #if !defined(WCHAR_MAX)
 #   error WCHAR_MAX not defined!
 #endif
     // cope with VC++ 7.1 or earlier having invalid WCHAR_MAX
 #if defined(_MSC_VER) && _MSC_VER <= 1310 // 7.1 or earlier
     return 2;
 #elif WCHAR_MAX > 0x10000
 
     if (word < 0x10000) {
         return 2;
     }
     if (word < 0x200000) {
         return 3;
     }
     if (word < 0x4000000) {
         return 4;
     }
     return 5;
 
 #else
     return 2;
 #endif
 }
 
 inline int get_cont_octet_out_count(wchar_t word)
 {
     return detail::get_cont_octet_out_count_impl<sizeof(wchar_t)>(word);
 }
 
 // copied from boost/detail/utf8_codecvt_facet.ipp
 // Copyright (c) 2001 Ronald Garcia, Indiana University (garcia@osl.iu.edu)
 // Andrew Lumsdaine, Indiana University (lums@osl.iu.edu).
 
 inline unsigned int get_octet_count(unsigned char lead_octet)
 {
     // if the 0-bit (MSB) is 0, then 1 character
     if (lead_octet <= 0x7f) return 1;
 
     // Otherwise the count number of consecutive 1 bits starting at MSB
 //    assert(0xc0 <= lead_octet && lead_octet <= 0xfd);
 
     if (0xc0 <= lead_octet && lead_octet <= 0xdf) return 2;
     else if (0xe0 <= lead_octet && lead_octet <= 0xef) return 3;
     else if (0xf0 <= lead_octet && lead_octet <= 0xf7) return 4;
     else if (0xf8 <= lead_octet && lead_octet <= 0xfb) return 5;
     else return 6;
 }
 
 inline bool invalid_continuing_octet(unsigned char octet_1) {
     return (octet_1 < 0x80|| 0xbf< octet_1);
 }
 
 inline unsigned int get_cont_octet_count(unsigned char lead_octet)
 {
     return get_octet_count(lead_octet) - 1;
 }
 
 inline const wchar_t * get_octet1_modifier_table() noexcept
 {
     static const wchar_t octet1_modifier_table[] = {
         0x00, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc
     };
     return octet1_modifier_table;
 }
 
 
 std::size_t size_as_utf8(const wchar_t * in, std::size_t size, error_code & ec)
 {
     std::size_t res = 0u;
     const auto from_end = in + size;
     for (auto from = in; from != from_end; from++)
         res += get_cont_octet_out_count(*from) + 1;
     return res;
 }
 
 std::size_t size_as_wide(const  char   * in, std::size_t size, error_code & ec)
 {
     const auto from = in;
     const auto from_end = from + size;
     const char * from_next = from;
     for (std::size_t char_count = 0u; from_next < from_end; ++char_count) {
         unsigned int octet_count = get_octet_count(*from_next);
         // The buffer may represent incomplete characters, so terminate early if one is found
         if (octet_count > static_cast<std::size_t>(from_end - from_next))
             break;
         from_next += octet_count;
     }
 
     return from_next - from;
 }
 
 std::size_t convert_to_utf8(const wchar_t * in, std::size_t size,
                             char   * out, std::size_t max_size, error_code & ec)
 {
 
     const wchar_t * from = in;
     const wchar_t * from_end = from + size;
     const wchar_t * & from_next = from;
     char * to = out;
     char * to_end = out + max_size;
     char * & to_next = to;
 
     const wchar_t * const octet1_modifier_table = get_octet1_modifier_table();
     wchar_t max_wchar = (std::numeric_limits<wchar_t>::max)();
     while (from != from_end && to != to_end) {
 
         // Check for invalid UCS-4 character
         if (*from  > max_wchar) {
             from_next = from;
             to_next = to;
             BOOST_PROCESS_V2_ASSIGN_EC(ec, error::invalid_character, error::get_utf8_category())
             return 0u;
         }
 
         int cont_octet_count = get_cont_octet_out_count(*from);
 
         // RG - comment this formula better
         int shift_exponent = cont_octet_count * 6;
 
         // Process the first character
         *to++ = static_cast<char>(octet1_modifier_table[cont_octet_count] +
                                   (unsigned char)(*from / (1 << shift_exponent)));
 
         // Process the continuation characters
         // Invariants: At the start of the loop:
         //   1) 'i' continuing octets have been generated
         //   2) '*to' points to the next location to place an octet
         //   3) shift_exponent is 6 more than needed for the next octet
         int i = 0;
         while (i != cont_octet_count && to != to_end) {
             shift_exponent -= 6;
             *to++ = static_cast<char>(0x80 + ((*from / (1 << shift_exponent)) % (1 << 6)));
             ++i;
         }
         // If we filled up the out buffer before encoding the character
         if (to == to_end && i != cont_octet_count) {
             from_next = from;
             to_next = to - (i + 1);
             BOOST_PROCESS_V2_ASSIGN_EC(ec, error::insufficient_buffer, error::get_utf8_category())
             return 0u;
         }
         ++from;
     }
     from_next = from;
     to_next = to;
 
     // Were we done or did we run out of destination space
     if (from != from_end)
         BOOST_PROCESS_V2_ASSIGN_EC(ec, error::insufficient_buffer, error::get_utf8_category())
 
     return to_next - out;
 }
 
 inline bool invalid_leading_octet(unsigned char octet_1) {
     return (0x7f < octet_1 && octet_1 < 0xc0) ||
            (octet_1 > 0xfd);
 }
 
 std::size_t convert_to_wide(const  char   * in, std::size_t size,
                             wchar_t * out, std::size_t max_size, error_code & ec)
 {
     const char * from = in;
     const char * from_end = from + size;
     const char * & from_next = from;
     wchar_t * to = out;
     wchar_t * to_end = out + max_size;
     wchar_t * & to_next = to;
 
     // Basic algorithm: The first octet determines how many
     // octets total make up the UCS-4 character. The remaining
     // "continuing octets" all begin with "10". To convert, subtract
     // the amount that specifies the number of octets from the first
     // octet. Subtract 0x80 (1000 0000) from each continuing octet,
     // then mash the whole lot together. Note that each continuing
     // octet only uses 6 bits as unique values, so only shift by
     // multiples of 6 to combine.
     const wchar_t * const octet1_modifier_table = detail::get_octet1_modifier_table();
     while (from != from_end && to != to_end) {
 
         // Error checking on the first octet
         if (invalid_leading_octet(*from)) {
             from_next = from;
             to_next = to;
             BOOST_PROCESS_V2_ASSIGN_EC(ec, error::invalid_character, error::get_utf8_category())
             return 0u;
         }
 
         // The first octet is adjusted by a value dependent upon
         // the number of "continuing octets" encoding the character
         const int cont_octet_count = get_cont_octet_count(*from);
 
         // The unsigned char conversion is necessary in case char is
         // signed (I learned this the hard way)
         wchar_t ucs_result =
                 (unsigned char)(*from++) - octet1_modifier_table[cont_octet_count];
 
         // Invariants:
         //   1) At the start of the loop, 'i' continuing characters have been
         //      processed
         //   2) *from points to the next continuing character to be processed.
         int i = 0;
         while (i != cont_octet_count && from != from_end) {
 
             // Error checking on continuing characters
             if (invalid_continuing_octet(*from)) {
                 from_next = from;
                 to_next = to;
                 BOOST_PROCESS_V2_ASSIGN_EC(ec, error::invalid_character, error::get_utf8_category())
                 return 0u;
             }
 
             ucs_result *= (1 << 6);
 
             // each continuing character has an extra (10xxxxxx)b attached to
             // it that must be removed.
             ucs_result += (unsigned char)(*from++) - 0x80;
             ++i;
         }
 
         // If the buffer ends with an incomplete unicode character...
         if (from == from_end && i != cont_octet_count) {
             // rewind "from" to before the current character translation
             from_next = from - (i + 1);
             to_next = to;
             BOOST_PROCESS_V2_ASSIGN_EC(ec, error::insufficient_buffer, error::get_utf8_category())
             return 0u;
         }
         *to++ = ucs_result;
     }
     from_next = from;
     to_next = to;
 
     if (from != from_end)
         BOOST_PROCESS_V2_ASSIGN_EC(ec, error::insufficient_buffer, error::get_utf8_category())
 
     return to_next - out;
 }
 
 #endif
 
 }
 
 BOOST_PROCESS_V2_END_NAMESPACE
 
 #endif //BOOST_PROCESS_V2_DETAIL_IMPL_UTF8_HPP

This page was automatically generated by the 2.3.7 LXR engine. The LXR team