/* vi: set sw=4 ts=4: */
/*
 * Unicode support routines.
 *
 * Copyright (C) 2009 Denys Vlasenko
 *
 * Licensed under GPLv2, see file LICENSE in this source tree.
 */
#include "libbb.h"
#include "unicode.h"

/* If it's not #defined as a constant in unicode.h... */
#ifndef unicode_status
uint8_t unicode_status;
#endif

/* This file is compiled only if UNICODE_SUPPORT is on.
 * We check other options and decide whether to use libc support
 * via locale, or use our own logic:
 */

#if ENABLE_UNICODE_USING_LOCALE

/* Unicode support using libc locale support. */

void FAST_FUNC reinit_unicode(const char *LANG)
{
        static const char unicode_0x394[] ALIGN1 = { 0xce, 0x94, 0 };
        size_t width;

        /* We pass "" instead of "C" because some libc's have
         * non-ASCII default locale for setlocale("") call
         * (this allows users of such libc to have Unicoded
         * system without having to mess with env).
         *
         * We set LC_CTYPE because (a) we may be called with $LC_CTYPE
         * value in LANG, not with $LC_ALL, (b) internationalized
         * LC_NUMERIC and LC_TIME are more PITA than benefit
         * (for one, some utilities have hard time with comma
         * used as a fractional separator).
         */
//TODO: avoid repeated calls by caching last string?
        setlocale(LC_CTYPE, LANG ? LANG : "");

        /* In unicode, this is a one character string */
        width = unicode_strlen(unicode_0x394);
        unicode_status = (width == 1 ? UNICODE_ON : UNICODE_OFF);
}

void FAST_FUNC init_unicode(void)
{
        /* Some people set only $LC_CTYPE, not $LC_ALL, because they want
         * only Unicode to be activated on their system, not the whole
         * shebang of wrong decimal points, strange date formats and so on.
         */
        if (unicode_status == UNICODE_UNKNOWN) {
                char *s = getenv("LC_ALL");
                if (!s) s = getenv("LC_CTYPE");
                if (!s) s = getenv("LANG");
                reinit_unicode(s);
        }
}

#else

/* Homegrown Unicode support. It knows only C and Unicode locales. */

# if ENABLE_FEATURE_CHECK_UNICODE_IN_ENV
void FAST_FUNC reinit_unicode(const char *LANG)
{
        unicode_status = UNICODE_OFF;
        if (!LANG || !(strstr(LANG, ".utf") || strstr(LANG, ".UTF")))
                return;
        unicode_status = UNICODE_ON;
}

void FAST_FUNC init_unicode(void)
{
        if (unicode_status == UNICODE_UNKNOWN) {
                char *s = getenv("LC_ALL");
                if (!s) s = getenv("LC_CTYPE");
                if (!s) s = getenv("LANG");
                reinit_unicode(s);
        }
}
# endif

static size_t wcrtomb_internal(char *s, wchar_t wc)
{
        int n, i;
        uint32_t v = wc;

        if (v <= 0x7f) {
                *s = v;
                return 1;
        }

        /* RFC 3629 says that Unicode ends at 10FFFF,
         * but we cover entire 32 bits */

        /* 4000000-FFFFFFFF -> 111111tt 10tttttt 10zzzzzz 10zzyyyy 10yyyyxx 10xxxxxx */
        /* 200000-3FFFFFF -> 111110tt 10zzzzzz 10zzyyyy 10yyyyxx 10xxxxxx */
        /* 10000-1FFFFF -> 11110zzz 10zzyyyy 10yyyyxx 10xxxxxx */
        /* 800-FFFF -> 1110yyyy 10yyyyxx 10xxxxxx */
        /* 80-7FF -> 110yyyxx 10xxxxxx */

        /* How many bytes do we need? */
        n = 2;
        /* (0x80000000+ would result in n = 7, limiting n to 6) */
        while (v >= 0x800 && n < 6) {
                v >>= 5;
                n++;
        }
        /* Fill bytes n-1..1 */
        i = n;
        while (--i) {
                s[i] = (wc & 0x3f) | 0x80;
                wc >>= 6;
        }
        /* Fill byte 0 */
        s[0] = wc | (uint8_t)(0x3f00 >> n);
        return n;
}
size_t FAST_FUNC wcrtomb(char *s, wchar_t wc, mbstate_t *ps UNUSED_PARAM)
{
        if (unicode_status != UNICODE_ON) {
                *s = wc;
                return 1;
        }

        return wcrtomb_internal(s, wc);
}
size_t FAST_FUNC wcstombs(char *dest, const wchar_t *src, size_t n)
{
        size_t org_n = n;

        if (unicode_status != UNICODE_ON) {
                while (n) {
                        wchar_t c = *src++;
                        *dest++ = c;
                        if (c == 0)
                                break;
                        n--;
                }
                return org_n - n;
        }

        while (n >= MB_CUR_MAX) {
                wchar_t wc = *src++;
                size_t len = wcrtomb_internal(dest, wc);

                if (wc == L'\0')
                        return org_n - n;
                dest += len;
                n -= len;
        }
        while (n) {
                char tbuf[MB_CUR_MAX];
                wchar_t wc = *src++;
                size_t len = wcrtomb_internal(tbuf, wc);

                if (len > n)
                        break;
                memcpy(dest, tbuf, len);
                if (wc == L'\0')
                        return org_n - n;
                dest += len;
                n -= len;
        }
        return org_n - n;
}

# define ERROR_WCHAR (~(wchar_t)0)

static const char *mbstowc_internal(wchar_t *res, const char *src)
{
        int bytes;
        unsigned c = (unsigned char) *src++;

        if (c <= 0x7f) {
                *res = c;
                return src;
        }

        /* 80-7FF -> 110yyyxx 10xxxxxx */
        /* 800-FFFF -> 1110yyyy 10yyyyxx 10xxxxxx */
        /* 10000-1FFFFF -> 11110zzz 10zzyyyy 10yyyyxx 10xxxxxx */
        /* 200000-3FFFFFF -> 111110tt 10zzzzzz 10zzyyyy 10yyyyxx 10xxxxxx */
        /* 4000000-FFFFFFFF -> 111111tt 10tttttt 10zzzzzz 10zzyyyy 10yyyyxx 10xxxxxx */
        bytes = 0;
        do {
                c <<= 1;
                bytes++;
        } while ((c & 0x80) && bytes < 6);
        if (bytes == 1) {
                /* A bare "continuation" byte. Say, 80 */
                *res = ERROR_WCHAR;
                return src;
        }
        c = (uint8_t)(c) >> bytes;

        while (--bytes) {
                unsigned ch = (unsigned char) *src;
                if ((ch & 0xc0) != 0x80) {
                        /* Missing "continuation" byte. Example: e0 80 */
                        *res = ERROR_WCHAR;
                        return src;
                }
                c = (c << 6) + (ch & 0x3f);
                src++;
        }

        /* TODO */
        /* Need to check that c isn't produced by overlong encoding */
        /* Example: 11000000 10000000 converts to NUL */
        /* 11110000 10000000 10000100 10000000 converts to 0x100 */
        /* correct encoding: 11000100 10000000 */
        if (c <= 0x7f) { /* crude check */
                *res = ERROR_WCHAR;
                return src;
        }

        *res = c;
        return src;
}
size_t FAST_FUNC mbstowcs(wchar_t *dest, const char *src, size_t n)
{
        size_t org_n = n;

        if (unicode_status != UNICODE_ON) {
                while (n) {
                        unsigned char c = *src++;

                        if (dest)
                                *dest++ = c;
                        if (c == 0)
                                break;
                        n--;
                }
                return org_n - n;
        }

        while (n) {
                wchar_t wc;
                src = mbstowc_internal(&wc, src);
                if (wc == ERROR_WCHAR) /* error */
                        return (size_t) -1L;
                if (dest)
                        *dest++ = wc;
                if (wc == 0) /* end-of-string */
                        break;
                n--;
        }

        return org_n - n;
}

int FAST_FUNC iswspace(wint_t wc)
{
        return (unsigned)wc <= 0x7f && isspace(wc);
}

int FAST_FUNC iswalnum(wint_t wc)
{
        return (unsigned)wc <= 0x7f && isalnum(wc);
}

int FAST_FUNC iswpunct(wint_t wc)
{
        return (unsigned)wc <= 0x7f && ispunct(wc);
}


# if CONFIG_LAST_SUPPORTED_WCHAR >= 0x300
struct interval {
        uint16_t first;
        uint16_t last;
};

/* auxiliary function for binary search in interval table */
static int in_interval_table(unsigned ucs, const struct interval *table, unsigned max)
{
        unsigned min;
        unsigned mid;

        if (ucs < table[0].first || ucs > table[max].last)
                return 0;

        min = 0;
        while (max >= min) {
                mid = (min + max) / 2;
                if (ucs > table[mid].last)
                        min = mid + 1;
                else if (ucs < table[mid].first)
                        max = mid - 1;
                else
                        return 1;
        }
        return 0;
}

static int in_uint16_table(unsigned ucs, const uint16_t *table, unsigned max)
{
        unsigned min;
        unsigned mid;
        unsigned first, last;

        first = table[0] >> 2;
        if (ucs < first)
                return 0;
        last = (table[max] >> 2) + (table[max] & 3);
        if (ucs > last)
                return 0;

        min = 0;
        while (max >= min) {
                mid = (min + max) / 2;
                first = table[mid] >> 2;
                last = first + (table[mid] & 3);
                if (ucs > last)
                        min = mid + 1;
                else if (ucs < first)
                        max = mid - 1;
                else
                        return 1;
        }
        return 0;
}
# endif


/*
 * This is an implementation of wcwidth() and wcswidth() (defined in
 * IEEE Std 1002.1-2001) for Unicode.
 *
 * http://www.opengroup.org/onlinepubs/007904975/functions/wcwidth.html
 * http://www.opengroup.org/onlinepubs/007904975/functions/wcswidth.html
 *
 * In fixed-width output devices, Latin characters all occupy a single
 * "cell" position of equal width, whereas ideographic CJK characters
 * occupy two such cells. Interoperability between terminal-line
 * applications and (teletype-style) character terminals using the
 * UTF-8 encoding requires agreement on which character should advance
 * the cursor by how many cell positions. No established formal
 * standards exist at present on which Unicode character shall occupy
 * how many cell positions on character terminals. These routines are
 * a first attempt of defining such behavior based on simple rules
 * applied to data provided by the Unicode Consortium.
 *
 * For some graphical characters, the Unicode standard explicitly
 * defines a character-cell width via the definition of the East Asian
 * FullWidth (F), Wide (W), Half-width (H), and Narrow (Na) classes.
 * In all these cases, there is no ambiguity about which width a
 * terminal shall use. For characters in the East Asian Ambiguous (A)
 * class, the width choice depends purely on a preference of backward
 * compatibility with either historic CJK or Western practice.
 * Choosing single-width for these characters is easy to justify as
 * the appropriate long-term solution, as the CJK practice of
 * displaying these characters as double-width comes from historic
 * implementation simplicity (8-bit encoded characters were displayed
 * single-width and 16-bit ones double-width, even for Greek,
 * Cyrillic, etc.) and not any typographic considerations.
 *
 * Much less clear is the choice of width for the Not East Asian
 * (Neutral) class. Existing practice does not dictate a width for any
 * of these characters. It would nevertheless make sense
 * typographically to allocate two character cells to characters such
 * as for instance EM SPACE or VOLUME INTEGRAL, which cannot be
 * represented adequately with a single-width glyph. The following
 * routines at present merely assign a single-cell width to all
 * neutral characters, in the interest of simplicity. This is not
 * entirely satisfactory and should be reconsidered before
 * establishing a formal standard in this area. At the moment, the
 * decision which Not East Asian (Neutral) characters should be
 * represented by double-width glyphs cannot yet be answered by
 * applying a simple rule from the Unicode database content. Setting
 * up a proper standard for the behavior of UTF-8 character terminals
 * will require a careful analysis not only of each Unicode character,
 * but also of each presentation form, something the author of these
 * routines has avoided to do so far.
 *
 * http://www.unicode.org/unicode/reports/tr11/
 *
 * Markus Kuhn -- 2007-05-26 (Unicode 5.0)
 *
 * Permission to use, copy, modify, and distribute this software
 * for any purpose and without fee is hereby granted. The author
 * disclaims all warranties with regard to this software.
 *
 * Latest version: http://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
 */

/* Assigned Unicode character ranges:
 * Plane Range
 * 0       0000–FFFF   Basic Multilingual Plane
 * 1      10000–1FFFF  Supplementary Multilingual Plane
 * 2      20000–2FFFF  Supplementary Ideographic Plane
 * 3      30000-3FFFF  Tertiary Ideographic Plane (no chars assigned yet)
 * 4-13   40000–DFFFF  currently unassigned
 * 14     E0000–EFFFF  Supplementary Special-purpose Plane
 * 15     F0000–FFFFF  Supplementary Private Use Area-A
 * 16    100000–10FFFF Supplementary Private Use Area-B
 *
 * "Supplementary Special-purpose Plane currently contains non-graphical
 * characters in two blocks of 128 and 240 characters. The first block
 * is for language tag characters for use when language cannot be indicated
 * through other protocols (such as the xml:lang  attribute in XML).
 * The other block contains glyph variation selectors to indicate
 * an alternate glyph for a character that cannot be determined by context."
 *
 * In simpler terms: it is a tool to fix the "Han unification" mess
 * created by Unicode committee, to select Chinese/Japanese/Korean/Taiwan
 * version of a character. (They forgot that the whole purpose of the Unicode
 * was to be able to write all chars in one charset without such tricks).
 * Until East Asian users say it is actually necessary to support these
 * code points in console applications like busybox
 * (i.e. do these chars ever appear in filenames, hostnames, text files
 * and such?), we are treating these code points as invalid.
 *
 * Tertiary Ideographic Plane is also ignored for now,
 * until Unicode committee assigns something there.
 */
/* The following two functions define the column width of an ISO 10646
 * character as follows:
 *
 *    - The null character (U+0000) has a column width of 0.
 *
 *    - Other C0/C1 control characters and DEL will lead to a return
 *      value of -1.
 *
 *    - Non-spacing and enclosing combining characters (general
 *      category code Mn or Me in the Unicode database) have a
 *      column width of 0.
 *
 *    - SOFT HYPHEN (U+00AD) has a column width of 1.
 *
 *    - Other format characters (general category code Cf in the Unicode
 *      database) and ZERO WIDTH SPACE (U+200B) have a column width of 0.
 *
 *    - Hangul Jamo medial vowels and final consonants (U+1160-U+11FF)
 *      have a column width of 0.
 *
 *    - Spacing characters in the East Asian Wide (W) or East Asian
 *      Full-width (F) category as defined in Unicode Technical
 *      Report #11 have a column width of 2.
 *
 *    - All remaining characters (including all printable
 *      ISO 8859-1 and WGL4 characters, Unicode control characters,
 *      etc.) have a column width of 1.
 *
 * This implementation assumes that wchar_t characters are encoded
 * in ISO 10646.
 */
int FAST_FUNC wcwidth(unsigned ucs)
{
# if CONFIG_LAST_SUPPORTED_WCHAR >= 0x300
        /* sorted list of non-overlapping intervals of non-spacing characters */
        /* generated by "uniset +cat=Me +cat=Mn +cat=Cf -00AD +1160-11FF +200B c" */
#  define BIG_(a,b) { a, b },
#  define PAIR(a,b)
#  define ARRAY /* PAIR if < 0x4000 and no more than 4 chars big */ \
                BIG_(0x0300, 0x036F) \
                PAIR(0x0483, 0x0486) \
                PAIR(0x0488, 0x0489) \
                BIG_(0x0591, 0x05BD) \
                PAIR(0x05BF, 0x05BF) \
                PAIR(0x05C1, 0x05C2) \
                PAIR(0x05C4, 0x05C5) \
                PAIR(0x05C7, 0x05C7) \
                PAIR(0x0600, 0x0603) \
                BIG_(0x0610, 0x0615) \
                BIG_(0x064B, 0x065E) \
                PAIR(0x0670, 0x0670) \
                BIG_(0x06D6, 0x06E4) \
                PAIR(0x06E7, 0x06E8) \
                PAIR(0x06EA, 0x06ED) \
                PAIR(0x070F, 0x070F) \
                PAIR(0x0711, 0x0711) \
                BIG_(0x0730, 0x074A) \
                BIG_(0x07A6, 0x07B0) \
                BIG_(0x07EB, 0x07F3) \
                PAIR(0x0901, 0x0902) \
                PAIR(0x093C, 0x093C) \
                BIG_(0x0941, 0x0948) \
                PAIR(0x094D, 0x094D) \
                PAIR(0x0951, 0x0954) \
                PAIR(0x0962, 0x0963) \
                PAIR(0x0981, 0x0981) \
                PAIR(0x09BC, 0x09BC) \
                PAIR(0x09C1, 0x09C4) \
                PAIR(0x09CD, 0x09CD) \
                PAIR(0x09E2, 0x09E3) \
                PAIR(0x0A01, 0x0A02) \
                PAIR(0x0A3C, 0x0A3C) \
                PAIR(0x0A41, 0x0A42) \
                PAIR(0x0A47, 0x0A48) \
                PAIR(0x0A4B, 0x0A4D) \
                PAIR(0x0A70, 0x0A71) \
                PAIR(0x0A81, 0x0A82) \
                PAIR(0x0ABC, 0x0ABC) \
                BIG_(0x0AC1, 0x0AC5) \
                PAIR(0x0AC7, 0x0AC8) \
                PAIR(0x0ACD, 0x0ACD) \
                PAIR(0x0AE2, 0x0AE3) \
                PAIR(0x0B01, 0x0B01) \
                PAIR(0x0B3C, 0x0B3C) \
                PAIR(0x0B3F, 0x0B3F) \
                PAIR(0x0B41, 0x0B43) \
                PAIR(0x0B4D, 0x0B4D) \
                PAIR(0x0B56, 0x0B56) \
                PAIR(0x0B82, 0x0B82) \
                PAIR(0x0BC0, 0x0BC0) \
                PAIR(0x0BCD, 0x0BCD) \
                PAIR(0x0C3E, 0x0C40) \
                PAIR(0x0C46, 0x0C48) \
                PAIR(0x0C4A, 0x0C4D) \
                PAIR(0x0C55, 0x0C56) \
                PAIR(0x0CBC, 0x0CBC) \
                PAIR(0x0CBF, 0x0CBF) \
                PAIR(0x0CC6, 0x0CC6) \
                PAIR(0x0CCC, 0x0CCD) \
                PAIR(0x0CE2, 0x0CE3) \
                PAIR(0x0D41, 0x0D43) \
                PAIR(0x0D4D, 0x0D4D) \
                PAIR(0x0DCA, 0x0DCA) \
                PAIR(0x0DD2, 0x0DD4) \
                PAIR(0x0DD6, 0x0DD6) \
                PAIR(0x0E31, 0x0E31) \
                BIG_(0x0E34, 0x0E3A) \
                BIG_(0x0E47, 0x0E4E) \
                PAIR(0x0EB1, 0x0EB1) \
                BIG_(0x0EB4, 0x0EB9) \
                PAIR(0x0EBB, 0x0EBC) \
                BIG_(0x0EC8, 0x0ECD) \
                PAIR(0x0F18, 0x0F19) \
                PAIR(0x0F35, 0x0F35) \
                PAIR(0x0F37, 0x0F37) \
                PAIR(0x0F39, 0x0F39) \
                BIG_(0x0F71, 0x0F7E) \
                BIG_(0x0F80, 0x0F84) \
                PAIR(0x0F86, 0x0F87) \
                PAIR(0x0FC6, 0x0FC6) \
                BIG_(0x0F90, 0x0F97) \
                BIG_(0x0F99, 0x0FBC) \
                PAIR(0x102D, 0x1030) \
                PAIR(0x1032, 0x1032) \
                PAIR(0x1036, 0x1037) \
                PAIR(0x1039, 0x1039) \
                PAIR(0x1058, 0x1059) \
                BIG_(0x1160, 0x11FF) \
                PAIR(0x135F, 0x135F) \
                PAIR(0x1712, 0x1714) \
                PAIR(0x1732, 0x1734) \
                PAIR(0x1752, 0x1753) \
                PAIR(0x1772, 0x1773) \
                PAIR(0x17B4, 0x17B5) \
                BIG_(0x17B7, 0x17BD) \
                PAIR(0x17C6, 0x17C6) \
                BIG_(0x17C9, 0x17D3) \
                PAIR(0x17DD, 0x17DD) \
                PAIR(0x180B, 0x180D) \
                PAIR(0x18A9, 0x18A9) \
                PAIR(0x1920, 0x1922) \
                PAIR(0x1927, 0x1928) \
                PAIR(0x1932, 0x1932) \
                PAIR(0x1939, 0x193B) \
                PAIR(0x1A17, 0x1A18) \
                PAIR(0x1B00, 0x1B03) \
                PAIR(0x1B34, 0x1B34) \
                BIG_(0x1B36, 0x1B3A) \
                PAIR(0x1B3C, 0x1B3C) \
                PAIR(0x1B42, 0x1B42) \
                BIG_(0x1B6B, 0x1B73) \
                BIG_(0x1DC0, 0x1DCA) \
                PAIR(0x1DFE, 0x1DFF) \
                BIG_(0x200B, 0x200F) \
                BIG_(0x202A, 0x202E) \
                PAIR(0x2060, 0x2063) \
                BIG_(0x206A, 0x206F) \
                BIG_(0x20D0, 0x20EF) \
                BIG_(0x302A, 0x302F) \
                PAIR(0x3099, 0x309A) \
                /* Too big to be packed in PAIRs: */ \
                BIG_(0xA806, 0xA806) \
                BIG_(0xA80B, 0xA80B) \
                BIG_(0xA825, 0xA826) \
                BIG_(0xFB1E, 0xFB1E) \
                BIG_(0xFE00, 0xFE0F) \
                BIG_(0xFE20, 0xFE23) \
                BIG_(0xFEFF, 0xFEFF) \
                BIG_(0xFFF9, 0xFFFB)
        static const struct interval combining[] ALIGN4 = { ARRAY };
#  undef BIG_
#  undef PAIR
#  define BIG_(a,b)
#  define PAIR(a,b) (a << 2) | (b-a),
        static const uint16_t combining1[] ALIGN2 = { ARRAY };
#  undef BIG_
#  undef PAIR
#  define BIG_(a,b) char big_##a[b < 0x4000 && b-a <= 3 ? -1 : 1];
#  define PAIR(a,b) char pair##a[b >= 0x4000 || b-a > 3 ? -1 : 1];
        struct CHECK { ARRAY };
#  undef BIG_
#  undef PAIR
#  undef ARRAY
# endif

        if (ucs == 0)
                return 0;

        /* Test for 8-bit control characters (00-1f, 80-9f, 7f) */
        if ((ucs & ~0x80) < 0x20 || ucs == 0x7f)
                return -1;
        /* Quick abort if it is an obviously invalid char */
        if (ucs > CONFIG_LAST_SUPPORTED_WCHAR)
                return -1;

        /* Optimization: no combining chars below 0x300 */
        if (CONFIG_LAST_SUPPORTED_WCHAR < 0x300 || ucs < 0x300)
                return 1;

# if CONFIG_LAST_SUPPORTED_WCHAR >= 0x300
        /* Binary search in table of non-spacing characters */
        if (in_interval_table(ucs, combining, ARRAY_SIZE(combining) - 1))
                return 0;
        if (in_uint16_table(ucs, combining1, ARRAY_SIZE(combining1) - 1))
                return 0;

        /* Optimization: all chars below 0x1100 are not double-width */
        if (CONFIG_LAST_SUPPORTED_WCHAR < 0x1100 || ucs < 0x1100)
                return 1;

#  if CONFIG_LAST_SUPPORTED_WCHAR >= 0x1100
        /* Invalid code points: */
        /* High (d800..dbff) and low (dc00..dfff) surrogates (valid only in UTF16) */
        /* Private Use Area (e000..f8ff) */
        /* Noncharacters fdd0..fdef */
        if ((CONFIG_LAST_SUPPORTED_WCHAR >= 0xd800 && ucs >= 0xd800 && ucs <= 0xf8ff)
         || (CONFIG_LAST_SUPPORTED_WCHAR >= 0xfdd0 && ucs >= 0xfdd0 && ucs <= 0xfdef)
        ) {
                return -1;
        }
        /* 0xfffe and 0xffff in every plane are invalid */
        if (CONFIG_LAST_SUPPORTED_WCHAR >= 0xfffe && ((ucs & 0xfffe) == 0xfffe)) {
                return -1;
        }

#   if CONFIG_LAST_SUPPORTED_WCHAR >= 0x10000
        if (ucs >= 0x10000) {
                /* Combining chars in Supplementary Multilingual Plane 0x1xxxx */
                static const struct interval combining0x10000[] ALIGN4 = {
                        { 0x0A01, 0x0A03 }, { 0x0A05, 0x0A06 }, { 0x0A0C, 0x0A0F },
                        { 0x0A38, 0x0A3A }, { 0x0A3F, 0x0A3F }, { 0xD167, 0xD169 },
                        { 0xD173, 0xD182 }, { 0xD185, 0xD18B }, { 0xD1AA, 0xD1AD },
                        { 0xD242, 0xD244 }
                };
                /* Binary search in table of non-spacing characters in Supplementary Multilingual Plane */
                if (in_interval_table(ucs ^ 0x10000, combining0x10000, ARRAY_SIZE(combining0x10000) - 1))
                        return 0;
                /* Check a few non-spacing chars in Supplementary Special-purpose Plane 0xExxxx */
                if (CONFIG_LAST_SUPPORTED_WCHAR >= 0xE0001
                 && (  ucs == 0xE0001
                    || (ucs >= 0xE0020 && ucs <= 0xE007F)
                    || (ucs >= 0xE0100 && ucs <= 0xE01EF)
                    )
                ) {
                        return 0;
                }
        }
#   endif

        /* If we arrive here, ucs is not a combining or C0/C1 control character.
         * Check whether it's 1 char or 2-shar wide.
         */
        return 1 +
                (  (/*ucs >= 0x1100 &&*/ ucs <= 0x115f) /* Hangul Jamo init. consonants */
                || ucs == 0x2329 /* left-pointing angle bracket; also CJK punct. char */
                || ucs == 0x232a /* right-pointing angle bracket; also CJK punct. char */
#   if CONFIG_LAST_SUPPORTED_WCHAR >= 0x2e80
                || (ucs >= 0x2e80 && ucs <= 0xa4cf && ucs != 0x303f) /* CJK ... Yi */
#   endif
#   if CONFIG_LAST_SUPPORTED_WCHAR >= 0xac00
                || (ucs >= 0xac00 && ucs <= 0xd7a3) /* Hangul Syllables */
#   endif
#   if CONFIG_LAST_SUPPORTED_WCHAR >= 0xf900
                || (ucs >= 0xf900 && ucs <= 0xfaff) /* CJK Compatibility Ideographs */
                || (ucs >= 0xfe10 && ucs <= 0xfe19) /* Vertical forms */
                || (ucs >= 0xfe30 && ucs <= 0xfe6f) /* CJK Compatibility Forms */
                || (ucs >= 0xff00 && ucs <= 0xff60) /* Fullwidth Forms */
                || (ucs >= 0xffe0 && ucs <= 0xffe6)
#   endif
#   if CONFIG_LAST_SUPPORTED_WCHAR >= 0x20000
                || ((ucs >> 17) == (2 >> 1)) /* 20000..3ffff: Supplementary and Tertiary Ideographic Planes */
#   endif
                );
#  endif /* >= 0x1100 */
# endif /* >= 0x300 */
}


# if ENABLE_UNICODE_BIDI_SUPPORT
int FAST_FUNC unicode_bidi_isrtl(wint_t wc)
{
        /* ranges taken from
         * http://www.unicode.org/Public/5.2.0/ucd/extracted/DerivedBidiClass.txt
         * Bidi_Class=Left_To_Right | Bidi_Class=Arabic_Letter
         */
#  define BIG_(a,b) { a, b },
#  define PAIR(a,b)
#  define ARRAY \
                PAIR(0x0590, 0x0590) \
                PAIR(0x05BE, 0x05BE) \
                PAIR(0x05C0, 0x05C0) \
                PAIR(0x05C3, 0x05C3) \
                PAIR(0x05C6, 0x05C6) \
                BIG_(0x05C8, 0x05FF) \
                PAIR(0x0604, 0x0605) \
                PAIR(0x0608, 0x0608) \
                PAIR(0x060B, 0x060B) \
                PAIR(0x060D, 0x060D) \
                BIG_(0x061B, 0x064A) \
                PAIR(0x065F, 0x065F) \
                PAIR(0x066D, 0x066F) \
                BIG_(0x0671, 0x06D5) \
                PAIR(0x06E5, 0x06E6) \
                PAIR(0x06EE, 0x06EF) \
                BIG_(0x06FA, 0x070E) \
                PAIR(0x0710, 0x0710) \
                BIG_(0x0712, 0x072F) \
                BIG_(0x074B, 0x07A5) \
                BIG_(0x07B1, 0x07EA) \
                PAIR(0x07F4, 0x07F5) \
                BIG_(0x07FA, 0x0815) \
                PAIR(0x081A, 0x081A) \
                PAIR(0x0824, 0x0824) \
                PAIR(0x0828, 0x0828) \
                BIG_(0x082E, 0x08FF) \
                PAIR(0x200F, 0x200F) \
                PAIR(0x202B, 0x202B) \
                PAIR(0x202E, 0x202E) \
                BIG_(0xFB1D, 0xFB1D) \
                BIG_(0xFB1F, 0xFB28) \
                BIG_(0xFB2A, 0xFD3D) \
                BIG_(0xFD40, 0xFDCF) \
                BIG_(0xFDC8, 0xFDCF) \
                BIG_(0xFDF0, 0xFDFC) \
                BIG_(0xFDFE, 0xFDFF) \
                BIG_(0xFE70, 0xFEFE)
                /* Probably not necessary
                {0x10800, 0x1091E},
                {0x10920, 0x10A00},
                {0x10A04, 0x10A04},
                {0x10A07, 0x10A0B},
                {0x10A10, 0x10A37},
                {0x10A3B, 0x10A3E},
                {0x10A40, 0x10A7F},
                {0x10B36, 0x10B38},
                {0x10B40, 0x10E5F},
                {0x10E7F, 0x10FFF},
                {0x1E800, 0x1EFFF}
                */
        static const struct interval rtl_b[] ALIGN4 = { ARRAY };
#  undef BIG_
#  undef PAIR
#  define BIG_(a,b)
#  define PAIR(a,b) (a << 2) | (b-a),
        static const uint16_t rtl_p[] ALIGN2 = { ARRAY };
#  undef BIG_
#  undef PAIR
#  define BIG_(a,b) char big_##a[b < 0x4000 && b-a <= 3 ? -1 : 1];
#  define PAIR(a,b) char pair##a[b >= 0x4000 || b-a > 3 ? -1 : 1];
        struct CHECK { ARRAY };
#  undef BIG_
#  undef PAIR
#  undef ARRAY

        if (in_interval_table(wc, rtl_b, ARRAY_SIZE(rtl_b) - 1))
                return 1;
        if (in_uint16_table(wc, rtl_p, ARRAY_SIZE(rtl_p) - 1))
                return 1;
        return 0;
}

#  if ENABLE_UNICODE_NEUTRAL_TABLE
int FAST_FUNC unicode_bidi_is_neutral_wchar(wint_t wc)
{
        /* ranges taken from
         * http://www.unicode.org/Public/5.2.0/ucd/extracted/DerivedBidiClass.txt
         * Bidi_Classes: Paragraph_Separator, Segment_Separator,
         * White_Space, Other_Neutral, European_Number, European_Separator,
         * European_Terminator, Arabic_Number, Common_Separator
         */
#  define BIG_(a,b) { a, b },
#  define PAIR(a,b)
#  define ARRAY \
                BIG_(0x0009, 0x000D) \
                BIG_(0x001C, 0x0040) \
                BIG_(0x005B, 0x0060) \
                PAIR(0x007B, 0x007E) \
                PAIR(0x0085, 0x0085) \
                BIG_(0x00A0, 0x00A9) \
                PAIR(0x00AB, 0x00AC) \
                BIG_(0x00AE, 0x00B4) \
                PAIR(0x00B6, 0x00B9) \
                BIG_(0x00BB, 0x00BF) \
                PAIR(0x00D7, 0x00D7) \
                PAIR(0x00F7, 0x00F7) \
                PAIR(0x02B9, 0x02BA) \
                BIG_(0x02C2, 0x02CF) \
                BIG_(0x02D2, 0x02DF) \
                BIG_(0x02E5, 0x02FF) \
                PAIR(0x0374, 0x0375) \
                PAIR(0x037E, 0x037E) \
                PAIR(0x0384, 0x0385) \
                PAIR(0x0387, 0x0387) \
                PAIR(0x03F6, 0x03F6) \
                PAIR(0x058A, 0x058A) \
                PAIR(0x0600, 0x0603) \
                PAIR(0x0606, 0x0607) \
                PAIR(0x0609, 0x060A) \
                PAIR(0x060C, 0x060C) \
                PAIR(0x060E, 0x060F) \
                BIG_(0x0660, 0x066C) \
                PAIR(0x06DD, 0x06DD) \
                PAIR(0x06E9, 0x06E9) \
                BIG_(0x06F0, 0x06F9) \
                PAIR(0x07F6, 0x07F9) \
                PAIR(0x09F2, 0x09F3) \
                PAIR(0x09FB, 0x09FB) \
                PAIR(0x0AF1, 0x0AF1) \
                BIG_(0x0BF3, 0x0BFA) \
                BIG_(0x0C78, 0x0C7E) \
                PAIR(0x0CF1, 0x0CF2) \
                PAIR(0x0E3F, 0x0E3F) \
                PAIR(0x0F3A, 0x0F3D) \
                BIG_(0x1390, 0x1400) \
                PAIR(0x1680, 0x1680) \
                PAIR(0x169B, 0x169C) \
                PAIR(0x17DB, 0x17DB) \
                BIG_(0x17F0, 0x17F9) \
                BIG_(0x1800, 0x180A) \
                PAIR(0x180E, 0x180E) \
                PAIR(0x1940, 0x1940) \
                PAIR(0x1944, 0x1945) \
                BIG_(0x19DE, 0x19FF) \
                PAIR(0x1FBD, 0x1FBD) \
                PAIR(0x1FBF, 0x1FC1) \
                PAIR(0x1FCD, 0x1FCF) \
                PAIR(0x1FDD, 0x1FDF) \
                PAIR(0x1FED, 0x1FEF) \
                PAIR(0x1FFD, 0x1FFE) \
                BIG_(0x2000, 0x200A) \
                BIG_(0x2010, 0x2029) \
                BIG_(0x202F, 0x205F) \
                PAIR(0x2070, 0x2070) \
                BIG_(0x2074, 0x207E) \
                BIG_(0x2080, 0x208E) \
                BIG_(0x20A0, 0x20B8) \
                PAIR(0x2100, 0x2101) \
                PAIR(0x2103, 0x2106) \
                PAIR(0x2108, 0x2109) \
                PAIR(0x2114, 0x2114) \
                PAIR(0x2116, 0x2118) \
                BIG_(0x211E, 0x2123) \
                PAIR(0x2125, 0x2125) \
                PAIR(0x2127, 0x2127) \
                PAIR(0x2129, 0x2129) \
                PAIR(0x212E, 0x212E) \
                PAIR(0x213A, 0x213B) \
                BIG_(0x2140, 0x2144) \
                PAIR(0x214A, 0x214D) \
                BIG_(0x2150, 0x215F) \
                PAIR(0x2189, 0x2189) \
                BIG_(0x2190, 0x2335) \
                BIG_(0x237B, 0x2394) \
                BIG_(0x2396, 0x23E8) \
                BIG_(0x2400, 0x2426) \
                BIG_(0x2440, 0x244A) \
                BIG_(0x2460, 0x249B) \
                BIG_(0x24EA, 0x26AB) \
                BIG_(0x26AD, 0x26CD) \
                BIG_(0x26CF, 0x26E1) \
                PAIR(0x26E3, 0x26E3) \
                BIG_(0x26E8, 0x26FF) \
                PAIR(0x2701, 0x2704) \
                PAIR(0x2706, 0x2709) \
                BIG_(0x270C, 0x2727) \
                BIG_(0x2729, 0x274B) \
                PAIR(0x274D, 0x274D) \
                PAIR(0x274F, 0x2752) \
                BIG_(0x2756, 0x275E) \
                BIG_(0x2761, 0x2794) \
                BIG_(0x2798, 0x27AF) \
                BIG_(0x27B1, 0x27BE) \
                BIG_(0x27C0, 0x27CA) \
                PAIR(0x27CC, 0x27CC) \
                BIG_(0x27D0, 0x27FF) \
                BIG_(0x2900, 0x2B4C) \
                BIG_(0x2B50, 0x2B59) \
                BIG_(0x2CE5, 0x2CEA) \
                BIG_(0x2CF9, 0x2CFF) \
                BIG_(0x2E00, 0x2E99) \
                BIG_(0x2E9B, 0x2EF3) \
                BIG_(0x2F00, 0x2FD5) \
                BIG_(0x2FF0, 0x2FFB) \
                BIG_(0x3000, 0x3004) \
                BIG_(0x3008, 0x3020) \
                PAIR(0x3030, 0x3030) \
                PAIR(0x3036, 0x3037) \
                PAIR(0x303D, 0x303D) \
                PAIR(0x303E, 0x303F) \
                PAIR(0x309B, 0x309C) \
                PAIR(0x30A0, 0x30A0) \
                PAIR(0x30FB, 0x30FB) \
                BIG_(0x31C0, 0x31E3) \
                PAIR(0x321D, 0x321E) \
                BIG_(0x3250, 0x325F) \
                PAIR(0x327C, 0x327E) \
                BIG_(0x32B1, 0x32BF) \
                PAIR(0x32CC, 0x32CF) \
                PAIR(0x3377, 0x337A) \
                PAIR(0x33DE, 0x33DF) \
                PAIR(0x33FF, 0x33FF) \
                BIG_(0x4DC0, 0x4DFF) \
                BIG_(0xA490, 0xA4C6) \
                BIG_(0xA60D, 0xA60F) \
                BIG_(0xA673, 0xA673) \
                BIG_(0xA67E, 0xA67F) \
                BIG_(0xA700, 0xA721) \
                BIG_(0xA788, 0xA788) \
                BIG_(0xA828, 0xA82B) \
                BIG_(0xA838, 0xA839) \
                BIG_(0xA874, 0xA877) \
                BIG_(0xFB29, 0xFB29) \
                BIG_(0xFD3E, 0xFD3F) \
                BIG_(0xFDFD, 0xFDFD) \
                BIG_(0xFE10, 0xFE19) \
                BIG_(0xFE30, 0xFE52) \
                BIG_(0xFE54, 0xFE66) \
                BIG_(0xFE68, 0xFE6B) \
                BIG_(0xFF01, 0xFF20) \
                BIG_(0xFF3B, 0xFF40) \
                BIG_(0xFF5B, 0xFF65) \
                BIG_(0xFFE0, 0xFFE6) \
                BIG_(0xFFE8, 0xFFEE) \
                BIG_(0xFFF9, 0xFFFD)
                /*
                {0x10101, 0x10101},
                {0x10140, 0x1019B},
                {0x1091F, 0x1091F},
                {0x10B39, 0x10B3F},
                {0x10E60, 0x10E7E},
                {0x1D200, 0x1D241},
                {0x1D245, 0x1D245},
                {0x1D300, 0x1D356},
                {0x1D6DB, 0x1D6DB},
                {0x1D715, 0x1D715},
                {0x1D74F, 0x1D74F},
                {0x1D789, 0x1D789},
                {0x1D7C3, 0x1D7C3},
                {0x1D7CE, 0x1D7FF},
                {0x1F000, 0x1F02B},
                {0x1F030, 0x1F093},
                {0x1F100, 0x1F10A}
                */
        static const struct interval neutral_b[] ALIGN4 = { ARRAY };
#  undef BIG_
#  undef PAIR
#  define BIG_(a,b)
#  define PAIR(a,b) (a << 2) | (b-a),
        static const uint16_t neutral_p[] ALIGN2 = { ARRAY };
#  undef BIG_
#  undef PAIR
#  define BIG_(a,b) char big_##a[b < 0x4000 && b-a <= 3 ? -1 : 1];
#  define PAIR(a,b) char pair##a[b >= 0x4000 || b-a > 3 ? -1 : 1];
        struct CHECK { ARRAY };
#  undef BIG_
#  undef PAIR
#  undef ARRAY

        if (in_interval_table(wc, neutral_b, ARRAY_SIZE(neutral_b) - 1))
                return 1;
        if (in_uint16_table(wc, neutral_p, ARRAY_SIZE(neutral_p) - 1))
                return 1;
        return 0;
}
#  endif

# endif /* UNICODE_BIDI_SUPPORT */

#endif /* Homegrown Unicode support */


/* The rest is mostly same for libc and for "homegrown" support */

size_t FAST_FUNC unicode_strlen(const char *string)
{
        size_t width = mbstowcs(NULL, string, INT_MAX);
        if (width == (size_t)-1L)
                return strlen(string);

        return width;
}

size_t FAST_FUNC unicode_strwidth(const char *string)
{
        uni_stat_t uni_stat;
        printable_string2(&uni_stat, string);
        return uni_stat.unicode_width;
}

static char* FAST_FUNC unicode_conv_to_printable2(uni_stat_t *stats, const char *src, unsigned width, int flags)
{
        char *dst;
        unsigned dst_len;
        unsigned uni_count;
        unsigned uni_width;

        if (unicode_status != UNICODE_ON) {
                char *d;
                if (flags & UNI_FLAG_PAD) {
                        d = dst = xmalloc(width + 1);
                        while ((int)--width >= 0) {
                                unsigned char c = *src;
                                if (c == '\0') {
                                        do
                                                *d++ = ' ';
                                        while ((int)--width >= 0);
                                        break;
                                }
                                *d++ = (c >= ' ' && c < 0x7f) ? c : '?';
                                src++;
                        }
                        *d = '\0';
                } else {
                        d = dst = xstrndup(src, width);
                        while (*d) {
                                unsigned char c = *d;
                                if (c < ' ' || c >= 0x7f)
                                        *d = '?';
                                d++;
                        }
                }
                if (stats) {
                        stats->byte_count = (d - dst);
                        stats->unicode_count = (d - dst);
                        stats->unicode_width = (d - dst);
                }
                return dst;
        }

        dst = NULL;
        uni_count = uni_width = 0;
        dst_len = 0;
        while (1) {
                int w;
                wchar_t wc;

#if ENABLE_UNICODE_USING_LOCALE
                {
                        mbstate_t mbst = { 0 };
                        ssize_t rc = mbsrtowcs(&wc, &src, 1, &mbst);
                        /* If invalid sequence is seen: -1 is returned,
                         * src points to the invalid sequence, errno = EILSEQ.
                         * Else number of wchars (excluding terminating L'\0')
                         * written to dest is returned.
                         * If len (here: 1) non-L'\0' wchars stored at dest,
                         * src points to the next char to be converted.
                         * If string is completely converted: src = NULL.
                         */
                        if (rc == 0) /* end-of-string */
                                break;
                        if (rc < 0) { /* error */
                                src++;
                                goto subst;
                        }
                        if (!iswprint(wc))
                                goto subst;
                }
#else
                src = mbstowc_internal(&wc, src);
                /* src is advanced to next mb char
                 * wc == ERROR_WCHAR: invalid sequence is seen
                 * else: wc is set
                 */
                if (wc == ERROR_WCHAR) /* error */
                        goto subst;
                if (wc == 0) /* end-of-string */
                        break;
#endif
                if (CONFIG_LAST_SUPPORTED_WCHAR && wc > CONFIG_LAST_SUPPORTED_WCHAR)
                        goto subst;
                w = wcwidth(wc);
                if ((ENABLE_UNICODE_COMBINING_WCHARS && w < 0) /* non-printable wchar */
                 || (!ENABLE_UNICODE_COMBINING_WCHARS && w <= 0)
                 || (!ENABLE_UNICODE_WIDE_WCHARS && w > 1)
                ) {
 subst:
                        wc = CONFIG_SUBST_WCHAR;
                        w = 1;
                }
                width -= w;
                /* Note: if width == 0, we still may add more chars,
                 * they may be zero-width or combining ones */
                if ((int)width < 0) {
                        /* can't add this wc, string would become longer than width */
                        width += w;
                        break;
                }

                uni_count++;
                uni_width += w;
                dst = xrealloc(dst, dst_len + MB_CUR_MAX);
#if ENABLE_UNICODE_USING_LOCALE
                {
                        mbstate_t mbst = { 0 };
                        dst_len += wcrtomb(&dst[dst_len], wc, &mbst);
                }
#else
                dst_len += wcrtomb_internal(&dst[dst_len], wc);
#endif
        }

        /* Pad to remaining width */
        if (flags & UNI_FLAG_PAD) {
                dst = xrealloc(dst, dst_len + width + 1);
                uni_count += width;
                uni_width += width;
                while ((int)--width >= 0) {
                        dst[dst_len++] = ' ';
                }
        }
        if (!dst) /* for example, if input was "" */
                dst = xzalloc(1);
        dst[dst_len] = '\0';
        if (stats) {
                stats->byte_count = dst_len;
                stats->unicode_count = uni_count;
                stats->unicode_width = uni_width;
        }

        return dst;
}
char* FAST_FUNC unicode_conv_to_printable(uni_stat_t *stats, const char *src)
{
        return unicode_conv_to_printable2(stats, src, INT_MAX, 0);
}
char* FAST_FUNC unicode_conv_to_printable_fixedwidth(/*uni_stat_t *stats,*/ const char *src, unsigned width)
{
        return unicode_conv_to_printable2(/*stats:*/ NULL, src, width, UNI_FLAG_PAD);
}

#ifdef UNUSED
char* FAST_FUNC unicode_conv_to_printable_maxwidth(uni_stat_t *stats, const char *src, unsigned maxwidth)
{
        return unicode_conv_to_printable2(stats, src, maxwidth, 0);
}

unsigned FAST_FUNC unicode_padding_to_width(unsigned width, const char *src)
{
        if (unicode_status != UNICODE_ON) {
                return width - strnlen(src, width);
        }

        while (1) {
                int w;
                wchar_t wc;

#if ENABLE_UNICODE_USING_LOCALE
                {
                        mbstate_t mbst = { 0 };
                        ssize_t rc = mbsrtowcs(&wc, &src, 1, &mbst);
                        if (rc <= 0) /* error, or end-of-string */
                                return width;
                }
#else
                src = mbstowc_internal(&wc, src);
                if (wc == ERROR_WCHAR || wc == 0) /* error, or end-of-string */
                        return width;
#endif
                w = wcwidth(wc);
                if (w < 0) /* non-printable wchar */
                        return width;
                width -= w;
                if ((int)width <= 0) /* string is longer than width */
                        return 0;
        }
}
#endif