File: C:/Users/fred/anaconda3/Library/include/boost/process/v2/detail/impl/utf8.ipp
// 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 ([email protected])
// Andrew Lumsdaine, Indiana University ([email protected]).
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