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Diffstat (limited to 'include/lib/modernjson/detail/input/input_adapters.hpp')
| -rw-r--r-- | include/lib/modernjson/detail/input/input_adapters.hpp | 398 |
1 files changed, 0 insertions, 398 deletions
diff --git a/include/lib/modernjson/detail/input/input_adapters.hpp b/include/lib/modernjson/detail/input/input_adapters.hpp deleted file mode 100644 index dfb8caf..0000000 --- a/include/lib/modernjson/detail/input/input_adapters.hpp +++ /dev/null @@ -1,398 +0,0 @@ -#pragma once - -#include <cassert> // assert -#include <cstddef> // size_t -#include <cstring> // strlen -#include <istream> // istream -#include <iterator> // begin, end, iterator_traits, random_access_iterator_tag, distance, next -#include <memory> // shared_ptr, make_shared, addressof -#include <numeric> // accumulate -#include <string> // string, char_traits -#include <type_traits> // enable_if, is_base_of, is_pointer, is_integral, remove_pointer -#include <utility> // pair, declval - -#include <lib/modernjson/detail/macro_scope.hpp> - -namespace nlohmann -{ -namespace detail -{ -/// the supported input formats -enum class input_format_t { json, cbor, msgpack, ubjson, bson }; - -//////////////////// -// input adapters // -//////////////////// - -/*! -@brief abstract input adapter interface - -Produces a stream of std::char_traits<char>::int_type characters from a -std::istream, a buffer, or some other input type. Accepts the return of -exactly one non-EOF character for future input. The int_type characters -returned consist of all valid char values as positive values (typically -unsigned char), plus an EOF value outside that range, specified by the value -of the function std::char_traits<char>::eof(). This value is typically -1, but -could be any arbitrary value which is not a valid char value. -*/ -struct input_adapter_protocol -{ - /// get a character [0,255] or std::char_traits<char>::eof(). - virtual std::char_traits<char>::int_type get_character() = 0; - virtual ~input_adapter_protocol() = default; -}; - -/// a type to simplify interfaces -using input_adapter_t = std::shared_ptr<input_adapter_protocol>; - -/*! -Input adapter for a (caching) istream. Ignores a UFT Byte Order Mark at -beginning of input. Does not support changing the underlying std::streambuf -in mid-input. Maintains underlying std::istream and std::streambuf to support -subsequent use of standard std::istream operations to process any input -characters following those used in parsing the JSON input. Clears the -std::istream flags; any input errors (e.g., EOF) will be detected by the first -subsequent call for input from the std::istream. -*/ -class input_stream_adapter : public input_adapter_protocol -{ - public: - ~input_stream_adapter() override - { - // clear stream flags; we use underlying streambuf I/O, do not - // maintain ifstream flags, except eof - is.clear(is.rdstate() & std::ios::eofbit); - } - - explicit input_stream_adapter(std::istream& i) - : is(i), sb(*i.rdbuf()) - {} - - // delete because of pointer members - input_stream_adapter(const input_stream_adapter&) = delete; - input_stream_adapter& operator=(input_stream_adapter&) = delete; - input_stream_adapter(input_stream_adapter&&) = delete; - input_stream_adapter& operator=(input_stream_adapter&&) = delete; - - // std::istream/std::streambuf use std::char_traits<char>::to_int_type, to - // ensure that std::char_traits<char>::eof() and the character 0xFF do not - // end up as the same value, eg. 0xFFFFFFFF. - std::char_traits<char>::int_type get_character() override - { - auto res = sb.sbumpc(); - // set eof manually, as we don't use the istream interface. - if (res == EOF) - { - is.clear(is.rdstate() | std::ios::eofbit); - } - return res; - } - - private: - /// the associated input stream - std::istream& is; - std::streambuf& sb; -}; - -/// input adapter for buffer input -class input_buffer_adapter : public input_adapter_protocol -{ - public: - input_buffer_adapter(const char* b, const std::size_t l) noexcept - : cursor(b), limit(b + l) - {} - - // delete because of pointer members - input_buffer_adapter(const input_buffer_adapter&) = delete; - input_buffer_adapter& operator=(input_buffer_adapter&) = delete; - input_buffer_adapter(input_buffer_adapter&&) = delete; - input_buffer_adapter& operator=(input_buffer_adapter&&) = delete; - ~input_buffer_adapter() override = default; - - std::char_traits<char>::int_type get_character() noexcept override - { - if (JSON_LIKELY(cursor < limit)) - { - return std::char_traits<char>::to_int_type(*(cursor++)); - } - - return std::char_traits<char>::eof(); - } - - private: - /// pointer to the current character - const char* cursor; - /// pointer past the last character - const char* const limit; -}; - -template<typename WideStringType, size_t T> -struct wide_string_input_helper -{ - // UTF-32 - static void fill_buffer(const WideStringType& str, size_t& current_wchar, std::array<std::char_traits<char>::int_type, 4>& utf8_bytes, size_t& utf8_bytes_index, size_t& utf8_bytes_filled) - { - utf8_bytes_index = 0; - - if (current_wchar == str.size()) - { - utf8_bytes[0] = std::char_traits<char>::eof(); - utf8_bytes_filled = 1; - } - else - { - // get the current character - const auto wc = static_cast<int>(str[current_wchar++]); - - // UTF-32 to UTF-8 encoding - if (wc < 0x80) - { - utf8_bytes[0] = wc; - utf8_bytes_filled = 1; - } - else if (wc <= 0x7FF) - { - utf8_bytes[0] = 0xC0 | ((wc >> 6) & 0x1F); - utf8_bytes[1] = 0x80 | (wc & 0x3F); - utf8_bytes_filled = 2; - } - else if (wc <= 0xFFFF) - { - utf8_bytes[0] = 0xE0 | ((wc >> 12) & 0x0F); - utf8_bytes[1] = 0x80 | ((wc >> 6) & 0x3F); - utf8_bytes[2] = 0x80 | (wc & 0x3F); - utf8_bytes_filled = 3; - } - else if (wc <= 0x10FFFF) - { - utf8_bytes[0] = 0xF0 | ((wc >> 18) & 0x07); - utf8_bytes[1] = 0x80 | ((wc >> 12) & 0x3F); - utf8_bytes[2] = 0x80 | ((wc >> 6) & 0x3F); - utf8_bytes[3] = 0x80 | (wc & 0x3F); - utf8_bytes_filled = 4; - } - else - { - // unknown character - utf8_bytes[0] = wc; - utf8_bytes_filled = 1; - } - } - } -}; - -template<typename WideStringType> -struct wide_string_input_helper<WideStringType, 2> -{ - // UTF-16 - static void fill_buffer(const WideStringType& str, size_t& current_wchar, std::array<std::char_traits<char>::int_type, 4>& utf8_bytes, size_t& utf8_bytes_index, size_t& utf8_bytes_filled) - { - utf8_bytes_index = 0; - - if (current_wchar == str.size()) - { - utf8_bytes[0] = std::char_traits<char>::eof(); - utf8_bytes_filled = 1; - } - else - { - // get the current character - const auto wc = static_cast<int>(str[current_wchar++]); - - // UTF-16 to UTF-8 encoding - if (wc < 0x80) - { - utf8_bytes[0] = wc; - utf8_bytes_filled = 1; - } - else if (wc <= 0x7FF) - { - utf8_bytes[0] = 0xC0 | ((wc >> 6)); - utf8_bytes[1] = 0x80 | (wc & 0x3F); - utf8_bytes_filled = 2; - } - else if (0xD800 > wc or wc >= 0xE000) - { - utf8_bytes[0] = 0xE0 | ((wc >> 12)); - utf8_bytes[1] = 0x80 | ((wc >> 6) & 0x3F); - utf8_bytes[2] = 0x80 | (wc & 0x3F); - utf8_bytes_filled = 3; - } - else - { - if (current_wchar < str.size()) - { - const auto wc2 = static_cast<int>(str[current_wchar++]); - const int charcode = 0x10000 + (((wc & 0x3FF) << 10) | (wc2 & 0x3FF)); - utf8_bytes[0] = 0xf0 | (charcode >> 18); - utf8_bytes[1] = 0x80 | ((charcode >> 12) & 0x3F); - utf8_bytes[2] = 0x80 | ((charcode >> 6) & 0x3F); - utf8_bytes[3] = 0x80 | (charcode & 0x3F); - utf8_bytes_filled = 4; - } - else - { - // unknown character - ++current_wchar; - utf8_bytes[0] = wc; - utf8_bytes_filled = 1; - } - } - } - } -}; - -template<typename WideStringType> -class wide_string_input_adapter : public input_adapter_protocol -{ - public: - explicit wide_string_input_adapter(const WideStringType& w) noexcept - : str(w) - {} - - std::char_traits<char>::int_type get_character() noexcept override - { - // check if buffer needs to be filled - if (utf8_bytes_index == utf8_bytes_filled) - { - fill_buffer<sizeof(typename WideStringType::value_type)>(); - - assert(utf8_bytes_filled > 0); - assert(utf8_bytes_index == 0); - } - - // use buffer - assert(utf8_bytes_filled > 0); - assert(utf8_bytes_index < utf8_bytes_filled); - return utf8_bytes[utf8_bytes_index++]; - } - - private: - template<size_t T> - void fill_buffer() - { - wide_string_input_helper<WideStringType, T>::fill_buffer(str, current_wchar, utf8_bytes, utf8_bytes_index, utf8_bytes_filled); - } - - /// the wstring to process - const WideStringType& str; - - /// index of the current wchar in str - std::size_t current_wchar = 0; - - /// a buffer for UTF-8 bytes - std::array<std::char_traits<char>::int_type, 4> utf8_bytes = {{0, 0, 0, 0}}; - - /// index to the utf8_codes array for the next valid byte - std::size_t utf8_bytes_index = 0; - /// number of valid bytes in the utf8_codes array - std::size_t utf8_bytes_filled = 0; -}; - -class input_adapter -{ - public: - // native support - - /// input adapter for input stream - input_adapter(std::istream& i) - : ia(std::make_shared<input_stream_adapter>(i)) {} - - /// input adapter for input stream - input_adapter(std::istream&& i) - : ia(std::make_shared<input_stream_adapter>(i)) {} - - input_adapter(const std::wstring& ws) - : ia(std::make_shared<wide_string_input_adapter<std::wstring>>(ws)) {} - - input_adapter(const std::u16string& ws) - : ia(std::make_shared<wide_string_input_adapter<std::u16string>>(ws)) {} - - input_adapter(const std::u32string& ws) - : ia(std::make_shared<wide_string_input_adapter<std::u32string>>(ws)) {} - - /// input adapter for buffer - template<typename CharT, - typename std::enable_if< - std::is_pointer<CharT>::value and - std::is_integral<typename std::remove_pointer<CharT>::type>::value and - sizeof(typename std::remove_pointer<CharT>::type) == 1, - int>::type = 0> - input_adapter(CharT b, std::size_t l) - : ia(std::make_shared<input_buffer_adapter>(reinterpret_cast<const char*>(b), l)) {} - - // derived support - - /// input adapter for string literal - template<typename CharT, - typename std::enable_if< - std::is_pointer<CharT>::value and - std::is_integral<typename std::remove_pointer<CharT>::type>::value and - sizeof(typename std::remove_pointer<CharT>::type) == 1, - int>::type = 0> - input_adapter(CharT b) - : input_adapter(reinterpret_cast<const char*>(b), - std::strlen(reinterpret_cast<const char*>(b))) {} - - /// input adapter for iterator range with contiguous storage - template<class IteratorType, - typename std::enable_if< - std::is_same<typename std::iterator_traits<IteratorType>::iterator_category, std::random_access_iterator_tag>::value, - int>::type = 0> - input_adapter(IteratorType first, IteratorType last) - { -#ifndef NDEBUG - // assertion to check that the iterator range is indeed contiguous, - // see http://stackoverflow.com/a/35008842/266378 for more discussion - const auto is_contiguous = std::accumulate( - first, last, std::pair<bool, int>(true, 0), - [&first](std::pair<bool, int> res, decltype(*first) val) - { - res.first &= (val == *(std::next(std::addressof(*first), res.second++))); - return res; - }).first; - assert(is_contiguous); -#endif - - // assertion to check that each element is 1 byte long - static_assert( - sizeof(typename std::iterator_traits<IteratorType>::value_type) == 1, - "each element in the iterator range must have the size of 1 byte"); - - const auto len = static_cast<size_t>(std::distance(first, last)); - if (JSON_LIKELY(len > 0)) - { - // there is at least one element: use the address of first - ia = std::make_shared<input_buffer_adapter>(reinterpret_cast<const char*>(&(*first)), len); - } - else - { - // the address of first cannot be used: use nullptr - ia = std::make_shared<input_buffer_adapter>(nullptr, len); - } - } - - /// input adapter for array - template<class T, std::size_t N> - input_adapter(T (&array)[N]) - : input_adapter(std::begin(array), std::end(array)) {} - - /// input adapter for contiguous container - template<class ContiguousContainer, typename - std::enable_if<not std::is_pointer<ContiguousContainer>::value and - std::is_base_of<std::random_access_iterator_tag, typename std::iterator_traits<decltype(std::begin(std::declval<ContiguousContainer const>()))>::iterator_category>::value, - int>::type = 0> - input_adapter(const ContiguousContainer& c) - : input_adapter(std::begin(c), std::end(c)) {} - - operator input_adapter_t() - { - return ia; - } - - private: - /// the actual adapter - input_adapter_t ia = nullptr; -}; -} // namespace detail -} // namespace nlohmann |