| // std::codecvt implementation details, GNU version -*- C++ -*- |
| |
| // Copyright (C) 2002-2021 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 3, 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. |
| |
| // Under Section 7 of GPL version 3, you are granted additional |
| // permissions described in the GCC Runtime Library Exception, version |
| // 3.1, as published by the Free Software Foundation. |
| |
| // You should have received a copy of the GNU General Public License and |
| // a copy of the GCC Runtime Library Exception along with this program; |
| // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
| // <http://www.gnu.org/licenses/>. |
| |
| // |
| // ISO C++ 14882: 22.2.1.5 - Template class codecvt |
| // |
| |
| // Written by Benjamin Kosnik <bkoz@redhat.com> |
| |
| #include <locale> |
| #include <cstdlib> // For MB_CUR_MAX |
| #include <climits> // For MB_LEN_MAX |
| #include <bits/c++locale_internal.h> |
| |
| namespace std _GLIBCXX_VISIBILITY(default) |
| { |
| _GLIBCXX_BEGIN_NAMESPACE_VERSION |
| |
| // Specializations. |
| #ifdef _GLIBCXX_USE_WCHAR_T |
| codecvt_base::result |
| codecvt<wchar_t, char, mbstate_t>:: |
| do_out(state_type& __state, 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 |
| { |
| result __ret = ok; |
| state_type __tmp_state(__state); |
| |
| #if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2) |
| __c_locale __old = __uselocale(_M_c_locale_codecvt); |
| #endif |
| |
| // wcsnrtombs is *very* fast but stops if encounters NUL characters: |
| // in case we fall back to wcrtomb and then continue, in a loop. |
| // NB: wcsnrtombs is a GNU extension |
| for (__from_next = __from, __to_next = __to; |
| __from_next < __from_end && __to_next < __to_end |
| && __ret == ok;) |
| { |
| const intern_type* __from_chunk_end = wmemchr(__from_next, L'\0', |
| __from_end - __from_next); |
| if (!__from_chunk_end) |
| __from_chunk_end = __from_end; |
| |
| __from = __from_next; |
| const size_t __conv = wcsnrtombs(__to_next, &__from_next, |
| __from_chunk_end - __from_next, |
| __to_end - __to_next, &__state); |
| if (__conv == static_cast<size_t>(-1)) |
| { |
| // In case of error, in order to stop at the exact place we |
| // have to start again from the beginning with a series of |
| // wcrtomb. |
| for (; __from < __from_next; ++__from) |
| __to_next += wcrtomb(__to_next, *__from, &__tmp_state); |
| __state = __tmp_state; |
| __ret = error; |
| } |
| else if (__from_next && __from_next < __from_chunk_end) |
| { |
| __to_next += __conv; |
| __ret = partial; |
| } |
| else |
| { |
| __from_next = __from_chunk_end; |
| __to_next += __conv; |
| } |
| |
| if (__from_next < __from_end && __ret == ok) |
| { |
| extern_type __buf[MB_LEN_MAX]; |
| __tmp_state = __state; |
| const size_t __conv2 = wcrtomb(__buf, *__from_next, &__tmp_state); |
| if (__conv2 > static_cast<size_t>(__to_end - __to_next)) |
| __ret = partial; |
| else |
| { |
| memcpy(__to_next, __buf, __conv2); |
| __state = __tmp_state; |
| __to_next += __conv2; |
| ++__from_next; |
| } |
| } |
| } |
| |
| #if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2) |
| __uselocale(__old); |
| #endif |
| |
| return __ret; |
| } |
| |
| codecvt_base::result |
| codecvt<wchar_t, char, mbstate_t>:: |
| do_in(state_type& __state, 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 |
| { |
| result __ret = ok; |
| state_type __tmp_state(__state); |
| |
| #if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2) |
| __c_locale __old = __uselocale(_M_c_locale_codecvt); |
| #endif |
| |
| // mbsnrtowcs is *very* fast but stops if encounters NUL characters: |
| // in case we store a L'\0' and then continue, in a loop. |
| // NB: mbsnrtowcs is a GNU extension |
| for (__from_next = __from, __to_next = __to; |
| __from_next < __from_end && __to_next < __to_end |
| && __ret == ok;) |
| { |
| const extern_type* __from_chunk_end; |
| __from_chunk_end = static_cast<const extern_type*>(memchr(__from_next, '\0', |
| __from_end |
| - __from_next)); |
| if (!__from_chunk_end) |
| __from_chunk_end = __from_end; |
| |
| __from = __from_next; |
| size_t __conv = mbsnrtowcs(__to_next, &__from_next, |
| __from_chunk_end - __from_next, |
| __to_end - __to_next, &__state); |
| if (__conv == static_cast<size_t>(-1)) |
| { |
| // In case of error, in order to stop at the exact place we |
| // have to start again from the beginning with a series of |
| // mbrtowc. |
| for (;; ++__to_next, __from += __conv) |
| { |
| __conv = mbrtowc(__to_next, __from, __from_end - __from, |
| &__tmp_state); |
| if (__conv == static_cast<size_t>(-1) |
| || __conv == static_cast<size_t>(-2)) |
| break; |
| } |
| __from_next = __from; |
| __state = __tmp_state; |
| __ret = error; |
| } |
| else if (__from_next && __from_next < __from_chunk_end) |
| { |
| // It is unclear what to return in this case (see DR 382). |
| __to_next += __conv; |
| __ret = partial; |
| } |
| else |
| { |
| __from_next = __from_chunk_end; |
| __to_next += __conv; |
| } |
| |
| if (__from_next < __from_end && __ret == ok) |
| { |
| if (__to_next < __to_end) |
| { |
| // XXX Probably wrong for stateful encodings |
| __tmp_state = __state; |
| ++__from_next; |
| *__to_next++ = L'\0'; |
| } |
| else |
| __ret = partial; |
| } |
| } |
| |
| #if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2) |
| __uselocale(__old); |
| #endif |
| |
| return __ret; |
| } |
| |
| int |
| codecvt<wchar_t, char, mbstate_t>:: |
| do_encoding() const throw() |
| { |
| // XXX This implementation assumes that the encoding is |
| // stateless and is either single-byte or variable-width. |
| int __ret = 0; |
| #if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2) |
| __c_locale __old = __uselocale(_M_c_locale_codecvt); |
| #endif |
| if (MB_CUR_MAX == 1) |
| __ret = 1; |
| #if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2) |
| __uselocale(__old); |
| #endif |
| return __ret; |
| } |
| |
| int |
| codecvt<wchar_t, char, mbstate_t>:: |
| do_max_length() const throw() |
| { |
| #if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2) |
| __c_locale __old = __uselocale(_M_c_locale_codecvt); |
| #endif |
| // XXX Probably wrong for stateful encodings. |
| int __ret = MB_CUR_MAX; |
| #if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2) |
| __uselocale(__old); |
| #endif |
| return __ret; |
| } |
| |
| int |
| codecvt<wchar_t, char, mbstate_t>:: |
| do_length(state_type& __state, const extern_type* __from, |
| const extern_type* __end, size_t __max) const |
| { |
| int __ret = 0; |
| state_type __tmp_state(__state); |
| |
| #if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2) |
| __c_locale __old = __uselocale(_M_c_locale_codecvt); |
| #endif |
| |
| // mbsnrtowcs is *very* fast but stops if encounters NUL characters: |
| // in case we advance past it and then continue, in a loop. |
| // NB: mbsnrtowcs is a GNU extension |
| |
| // A dummy internal buffer is needed in order for mbsnrtocws to consider |
| // its fourth parameter (it wouldn't with NULL as first parameter). |
| wchar_t* __to = static_cast<wchar_t*>(__builtin_alloca(sizeof(wchar_t) |
| * __max)); |
| while (__from < __end && __max) |
| { |
| const extern_type* __from_chunk_end; |
| __from_chunk_end = static_cast<const extern_type*>(memchr(__from, '\0', |
| __end |
| - __from)); |
| if (!__from_chunk_end) |
| __from_chunk_end = __end; |
| |
| const extern_type* __tmp_from = __from; |
| size_t __conv = mbsnrtowcs(__to, &__from, |
| __from_chunk_end - __from, |
| __max, &__state); |
| if (__conv == static_cast<size_t>(-1)) |
| { |
| // In case of error, in order to stop at the exact place we |
| // have to start again from the beginning with a series of |
| // mbrtowc. |
| for (__from = __tmp_from;; __from += __conv) |
| { |
| __conv = mbrtowc(0, __from, __end - __from, |
| &__tmp_state); |
| if (__conv == static_cast<size_t>(-1) |
| || __conv == static_cast<size_t>(-2)) |
| break; |
| } |
| __state = __tmp_state; |
| __ret += __from - __tmp_from; |
| break; |
| } |
| if (!__from) |
| __from = __from_chunk_end; |
| |
| __ret += __from - __tmp_from; |
| __max -= __conv; |
| |
| if (__from < __end && __max) |
| { |
| // XXX Probably wrong for stateful encodings |
| __tmp_state = __state; |
| ++__from; |
| ++__ret; |
| --__max; |
| } |
| } |
| |
| #if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2) |
| __uselocale(__old); |
| #endif |
| |
| return __ret; |
| } |
| #endif |
| |
| _GLIBCXX_END_NAMESPACE_VERSION |
| } // namespace |
