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62 lines
1.5 KiB
62 lines
1.5 KiB
#pragma once |
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#include <cstdint> |
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#include <string> |
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#include <utility> |
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#include "utils/stdcompat/string_view.hpp" |
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namespace devilution { |
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constexpr char32_t Utf8DecodeError = 0xD83F; |
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/** |
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* Decodes the first code point from UTF8-encoded input. |
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* |
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* Sets `len` to the length of the code point in bytes. |
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* Returns `Utf8DecodeError` on error. |
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*/ |
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char32_t DecodeFirstUtf8CodePoint(string_view input, uint8_t *len); |
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/** |
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* Decodes and removes the first code point from UTF8-encoded input. |
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*/ |
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inline char32_t ConsumeFirstUtf8CodePoint(string_view *input) |
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{ |
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uint8_t len; |
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const char32_t result = DecodeFirstUtf8CodePoint(*input, &len); |
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input->remove_prefix(len); |
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return result; |
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} |
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/** |
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* Returns true if this is a trailing byte in a UTF-8 code point encoding. |
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* |
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* A trailing byte is any byte that is not the heading byte. |
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*/ |
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inline bool IsTrailUtf8CodeUnit(char x) |
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{ |
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return static_cast<signed char>(x) < -0x40; |
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} |
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/** |
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* Returns the start byte index of the last code point in a UTF-8 string. |
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*/ |
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inline std::size_t FindLastUtf8Symbols(string_view input) |
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{ |
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if (input.empty()) |
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return 0; |
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std::size_t pos = input.size() - 1; |
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while (pos > 0 && IsTrailUtf8CodeUnit(input[pos])) |
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--pos; |
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return pos; |
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} |
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/** |
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* @brief Copy up to a given number of bytes from a UTF8 string, and zero terminate string |
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* @param bytes Max number of bytes to copy |
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*/ |
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void CopyUtf8(char *dest, string_view source, std::size_t bytes); |
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} // namespace devilution
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