/* MIT License * * Copyright (c) 2025 Tyge Løvset * * 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. */ // IWYU pragma: private, include "stc/utf8.h" #ifndef STC_UTF8_PRV_H_INCLUDED #define STC_UTF8_PRV_H_INCLUDED // The following functions assume valid utf8 strings: /* number of bytes in the utf8 codepoint from s */ STC_INLINE int utf8_chr_size(const char *s) { unsigned b = (uint8_t)*s; if (b < 0x80) return 1; /*if (b < 0xC2) return 0;*/ if (b < 0xE0) return 2; if (b < 0xF0) return 3; /*if (b < 0xF5)*/ return 4; /*return 0;*/ } /* number of codepoints in the utf8 string s */ STC_INLINE isize utf8_count(const char *s) { isize size = 0; while (*s) size += (*++s & 0xC0) != 0x80; return size; } STC_INLINE isize utf8_count_n(const char *s, isize nbytes) { isize size = 0; while ((nbytes-- != 0) & (*s != 0)) { size += (*++s & 0xC0) != 0x80; } return size; } STC_INLINE const char* utf8_at(const char *s, isize u8pos) { while ((u8pos > 0) & (*s != 0)) u8pos -= (*++s & 0xC0) != 0x80; return s; } STC_INLINE const char* utf8_offset(const char* s, isize u8pos) { int inc = 1; if (u8pos < 0) u8pos = -u8pos, inc = -1; while (u8pos && *s) u8pos -= (*(s += inc) & 0xC0) != 0x80; return s; } STC_INLINE isize utf8_to_index(const char* s, isize u8pos) { return utf8_at(s, u8pos) - s; } STC_INLINE csview utf8_subview(const char *s, isize u8pos, isize u8len) { csview span; span.buf = utf8_at(s, u8pos); span.size = utf8_to_index(span.buf, u8len); return span; } // ------------------------------------------------------ // The following requires linking with utf8 symbols. // To call them, either define i_import before including // one of cstr, csview, zsview, or link with src/libstc.o. /* decode next utf8 codepoint. https://bjoern.hoehrmann.de/utf-8/decoder/dfa */ typedef struct { uint32_t state, codep; } utf8_decode_t; extern const uint8_t utf8_dtab[]; /* utf8code.c */ #define utf8_ACCEPT 0 #define utf8_REJECT 12 extern bool utf8_valid(const char* s); extern bool utf8_valid_n(const char* s, isize nbytes); extern int utf8_encode(char *out, uint32_t c); extern int utf8_decode_codepoint(utf8_decode_t* d, const char* s, const char* end); extern int utf8_icompare(const csview s1, const csview s2); extern uint32_t utf8_peek_at(const char* s, isize u8offset); extern uint32_t utf8_casefold(uint32_t c); extern uint32_t utf8_tolower(uint32_t c); extern uint32_t utf8_toupper(uint32_t c); STC_INLINE bool utf8_isupper(uint32_t c) { return utf8_tolower(c) != c; } STC_INLINE bool utf8_islower(uint32_t c) { return utf8_toupper(c) != c; } STC_INLINE uint32_t utf8_decode(utf8_decode_t* d, const uint32_t byte) { const uint32_t type = utf8_dtab[byte]; d->codep = d->state ? (byte & 0x3fu) | (d->codep << 6) : (0xffU >> type) & byte; return d->state = utf8_dtab[256 + d->state + type]; } STC_INLINE uint32_t utf8_peek(const char* s) { utf8_decode_t d = {.state=0}; do { utf8_decode(&d, (uint8_t)*s++); } while (d.state > utf8_REJECT); return d.state == utf8_ACCEPT ? d.codep : 0xFFFD; } /* case-insensitive utf8 string comparison */ STC_INLINE int utf8_icmp(const char* s1, const char* s2) { return utf8_icompare(c_sv(s1, INTPTR_MAX), c_sv(s2, INTPTR_MAX)); } #endif // STC_UTF8_PRV_H_INCLUDED