tumbledemerald-legacy/tools/preproc/utf8.cpp
2022-05-19 17:14:13 +00:00

93 lines
3.4 KiB
C++

// Copyright (c) 2008-2009 Bjoern Hoehrmann <bjoern@hoehrmann.de>
// See http://bjoern.hoehrmann.de/utf-8/decoder/dfa/ for details.
//
// Copyright(c) 2016 YamaArashi
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
#include <cstdint>
#include "utf8.h"
static const unsigned char s_byteTypeTable[] =
{
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 00..1f
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 20..3f
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 40..5f
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 60..7f
1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9, // 80..9f
7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, // a0..bf
8,8,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, // c0..df
0xa,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x4,0x3,0x3, // e0..ef
0xb,0x6,0x6,0x6,0x5,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8, // f0..ff
};
const unsigned char s0 = 0 * 12;
const unsigned char s1 = 1 * 12;
const unsigned char s2 = 2 * 12;
const unsigned char s3 = 3 * 12;
const unsigned char s4 = 4 * 12;
const unsigned char s5 = 5 * 12;
const unsigned char s6 = 6 * 12;
const unsigned char s7 = 7 * 12;
const unsigned char s8 = 8 * 12;
static const unsigned char s_transitionTable[] =
{
s0,s1,s2,s3,s5,s8,s7,s1,s1,s1,s4,s6, // s0
s1,s1,s1,s1,s1,s1,s1,s1,s1,s1,s1,s1, // s1
s1,s0,s1,s1,s1,s1,s1,s0,s1,s0,s1,s1, // s2
s1,s2,s1,s1,s1,s1,s1,s2,s1,s2,s1,s1, // s3
s1,s1,s1,s1,s1,s1,s1,s2,s1,s1,s1,s1, // s4
s1,s2,s1,s1,s1,s1,s1,s1,s1,s2,s1,s1, // s5
s1,s1,s1,s1,s1,s1,s1,s3,s1,s3,s1,s1, // s6
s1,s3,s1,s1,s1,s1,s1,s3,s1,s3,s1,s1, // s7
s1,s3,s1,s1,s1,s1,s1,s1,s1,s1,s1,s1, // s8
};
// Decodes UTF-8 encoded Unicode code point at "s".
UnicodeChar DecodeUtf8(const char* s)
{
UnicodeChar unicodeChar;
int state = s0;
auto start = s;
do
{
unsigned char byte = *s++;
int type = s_byteTypeTable[byte];
if (state == s0)
unicodeChar.code = (0xFF >> type) & byte;
else
unicodeChar.code = (unicodeChar.code << 6) | (byte & 0x3F);
state = s_transitionTable[state + type];
if (state == s1)
{
unicodeChar.code = -1;
return unicodeChar;
}
} while (state != s0);
unicodeChar.encodingLength = s - start;
return unicodeChar;
}