//// Dis VM// File: utf8.h// Author: arr// #ifndef _DISVM_SRC_INCLUDE_UTF8_H_#define _DISVM_SRC_INCLUDE_UTF8_H_ #include <cstdint>#include "runtime.h" namespace disvm{    namespace runtime    {        namespace utf8        {            // As defined in http://tools.ietf.org/html/rfc3629            namespace constants            {                const disvm::runtime::rune_t multi_byte_value_mask = 0x3f;                 const disvm::runtime::rune_t max_codepoint_ascii = 0x7f;                const disvm::runtime::rune_t max_codepoint_2_byte = 0x7ff;                const disvm::runtime::rune_t max_codepoint_3_byte = 0xffff;                const disvm::runtime::rune_t max_codepoint_4_byte = 0x10ffff;                 const disvm::runtime::rune_t max_supported_codepoint = max_codepoint_4_byte;            };             // Lengths of a UTF-8 string            struct utf8_length_t            {                const std::size_t codepoint_count;                const std::size_t byte_count;            };             // Compute the number of codepoints in the supplied string            // See http://bjoern.hoehrmann.de/utf-8/decoder/dfa/ for details.            utf8_length_t count_codepoints(const uint8_t *str, const std::size_t max_len);             enum class decode_state_t            {                accept = 0,                reject = 12            };             // Decode a byte at a time to form a codepoint.            // See http://bjoern.hoehrmann.de/utf-8/decoder/dfa/ for details.            decode_state_t decode_step(decode_state_t &state, rune_t &codepoint, uint8_t byte);             // Decode the next codepoint in the supplied string.            // Returns number of characters in string consumed.            std::size_t decode(const uint8_t *str, rune_t &codepoint);             // Encode the rune into the supplied buffer.            // Returns updated pointer in the buffer or null on error.            uint8_t *encode(const rune_t rune, uint8_t *str);        }    }} #endif // _DISVM_SRC_INCLUDE_UTF8_H_