cosmopolitan/libc/str/wcwidth.c

64 lines
3 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/intrin/likely.h"
#include "libc/str/str.h"
#include "libc/str/unicode.h"
#include "libc/str/wcwidth_osx.internal.h"
extern const uint8_t kEastAsianWidth[];
extern const uint32_t kEastAsianWidthBits;
extern const uint8_t kCombiningChars[];
extern const uint32_t kCombiningCharsBits;
/**
* Returns cell width of monospace character.
*/
int wcwidth(wchar_t c) {
#if defined(__x86_64__) && !defined(__chibicc__)
if (LIKELY(32 <= c && c < 127)) {
return 1;
} else if (!c) {
return 0;
} else if ((uint32_t)c > 0x10FFFD || //
(0 < c && c < 32) || //
(0x7f <= c && c < 0xA0)) {
return -1;
} else if ((0 <= c && c < kCombiningCharsBits) &&
!!(kCombiningChars[c >> 3] & (1 << (c & 7)))) {
return 0;
} else if (0 <= c && c < kEastAsianWidthBits) {
return 1 + !!(kEastAsianWidth[c >> 3] & (1 << (c & 7)));
} else {
return 1;
}
#else
int res;
if (LIKELY(32 <= c && c < 127)) return 1;
if (VERY_UNLIKELY((uint32_t)c >= 0x100000)) {
if ((uint32_t)c <= 0x10FFFD) return 1;
return -1;
}
res = _wcwidth_osx(c);
if (VERY_UNLIKELY(!res)) {
if (!c) return 0;
if (iswcntrl(c)) return -1;
}
return res;
#endif
}