utf8.con commit Merge branch 'maint' of git://linux-nfs.org/~bfields/git (c477553)
   1#include "git-compat-util.h"
   2#include "utf8.h"
   3
   4/* This code is originally from http://www.cl.cam.ac.uk/~mgk25/ucs/ */
   5
   6typedef unsigned int ucs_char_t;  /* assuming 32bit int */
   7
   8struct interval {
   9  int first;
  10  int last;
  11};
  12
  13/* auxiliary function for binary search in interval table */
  14static int bisearch(ucs_char_t ucs, const struct interval *table, int max)
  15{
  16        int min = 0;
  17        int mid;
  18
  19        if (ucs < table[0].first || ucs > table[max].last)
  20                return 0;
  21        while (max >= min) {
  22                mid = (min + max) / 2;
  23                if (ucs > table[mid].last)
  24                        min = mid + 1;
  25                else if (ucs < table[mid].first)
  26                        max = mid - 1;
  27                else
  28                        return 1;
  29        }
  30
  31        return 0;
  32}
  33
  34/* The following two functions define the column width of an ISO 10646
  35 * character as follows:
  36 *
  37 *    - The null character (U+0000) has a column width of 0.
  38 *
  39 *    - Other C0/C1 control characters and DEL will lead to a return
  40 *      value of -1.
  41 *
  42 *    - Non-spacing and enclosing combining characters (general
  43 *      category code Mn or Me in the Unicode database) have a
  44 *      column width of 0.
  45 *
  46 *    - SOFT HYPHEN (U+00AD) has a column width of 1.
  47 *
  48 *    - Other format characters (general category code Cf in the Unicode
  49 *      database) and ZERO WIDTH SPACE (U+200B) have a column width of 0.
  50 *
  51 *    - Hangul Jamo medial vowels and final consonants (U+1160-U+11FF)
  52 *      have a column width of 0.
  53 *
  54 *    - Spacing characters in the East Asian Wide (W) or East Asian
  55 *      Full-width (F) category as defined in Unicode Technical
  56 *      Report #11 have a column width of 2.
  57 *
  58 *    - All remaining characters (including all printable
  59 *      ISO 8859-1 and WGL4 characters, Unicode control characters,
  60 *      etc.) have a column width of 1.
  61 *
  62 * This implementation assumes that ucs_char_t characters are encoded
  63 * in ISO 10646.
  64 */
  65
  66static int git_wcwidth(ucs_char_t ch)
  67{
  68        /*
  69         * Sorted list of non-overlapping intervals of non-spacing characters,
  70         * generated by
  71         *   "uniset +cat=Me +cat=Mn +cat=Cf -00AD +1160-11FF +200B c".
  72         */
  73        static const struct interval combining[] = {
  74                { 0x0300, 0x0357 }, { 0x035D, 0x036F }, { 0x0483, 0x0486 },
  75                { 0x0488, 0x0489 }, { 0x0591, 0x05A1 }, { 0x05A3, 0x05B9 },
  76                { 0x05BB, 0x05BD }, { 0x05BF, 0x05BF }, { 0x05C1, 0x05C2 },
  77                { 0x05C4, 0x05C4 }, { 0x0600, 0x0603 }, { 0x0610, 0x0615 },
  78                { 0x064B, 0x0658 }, { 0x0670, 0x0670 }, { 0x06D6, 0x06E4 },
  79                { 0x06E7, 0x06E8 }, { 0x06EA, 0x06ED }, { 0x070F, 0x070F },
  80                { 0x0711, 0x0711 }, { 0x0730, 0x074A }, { 0x07A6, 0x07B0 },
  81                { 0x0901, 0x0902 }, { 0x093C, 0x093C }, { 0x0941, 0x0948 },
  82                { 0x094D, 0x094D }, { 0x0951, 0x0954 }, { 0x0962, 0x0963 },
  83                { 0x0981, 0x0981 }, { 0x09BC, 0x09BC }, { 0x09C1, 0x09C4 },
  84                { 0x09CD, 0x09CD }, { 0x09E2, 0x09E3 }, { 0x0A01, 0x0A02 },
  85                { 0x0A3C, 0x0A3C }, { 0x0A41, 0x0A42 }, { 0x0A47, 0x0A48 },
  86                { 0x0A4B, 0x0A4D }, { 0x0A70, 0x0A71 }, { 0x0A81, 0x0A82 },
  87                { 0x0ABC, 0x0ABC }, { 0x0AC1, 0x0AC5 }, { 0x0AC7, 0x0AC8 },
  88                { 0x0ACD, 0x0ACD }, { 0x0AE2, 0x0AE3 }, { 0x0B01, 0x0B01 },
  89                { 0x0B3C, 0x0B3C }, { 0x0B3F, 0x0B3F }, { 0x0B41, 0x0B43 },
  90                { 0x0B4D, 0x0B4D }, { 0x0B56, 0x0B56 }, { 0x0B82, 0x0B82 },
  91                { 0x0BC0, 0x0BC0 }, { 0x0BCD, 0x0BCD }, { 0x0C3E, 0x0C40 },
  92                { 0x0C46, 0x0C48 }, { 0x0C4A, 0x0C4D }, { 0x0C55, 0x0C56 },
  93                { 0x0CBC, 0x0CBC }, { 0x0CBF, 0x0CBF }, { 0x0CC6, 0x0CC6 },
  94                { 0x0CCC, 0x0CCD }, { 0x0D41, 0x0D43 }, { 0x0D4D, 0x0D4D },
  95                { 0x0DCA, 0x0DCA }, { 0x0DD2, 0x0DD4 }, { 0x0DD6, 0x0DD6 },
  96                { 0x0E31, 0x0E31 }, { 0x0E34, 0x0E3A }, { 0x0E47, 0x0E4E },
  97                { 0x0EB1, 0x0EB1 }, { 0x0EB4, 0x0EB9 }, { 0x0EBB, 0x0EBC },
  98                { 0x0EC8, 0x0ECD }, { 0x0F18, 0x0F19 }, { 0x0F35, 0x0F35 },
  99                { 0x0F37, 0x0F37 }, { 0x0F39, 0x0F39 }, { 0x0F71, 0x0F7E },
 100                { 0x0F80, 0x0F84 }, { 0x0F86, 0x0F87 }, { 0x0F90, 0x0F97 },
 101                { 0x0F99, 0x0FBC }, { 0x0FC6, 0x0FC6 }, { 0x102D, 0x1030 },
 102                { 0x1032, 0x1032 }, { 0x1036, 0x1037 }, { 0x1039, 0x1039 },
 103                { 0x1058, 0x1059 }, { 0x1160, 0x11FF }, { 0x1712, 0x1714 },
 104                { 0x1732, 0x1734 }, { 0x1752, 0x1753 }, { 0x1772, 0x1773 },
 105                { 0x17B4, 0x17B5 }, { 0x17B7, 0x17BD }, { 0x17C6, 0x17C6 },
 106                { 0x17C9, 0x17D3 }, { 0x17DD, 0x17DD }, { 0x180B, 0x180D },
 107                { 0x18A9, 0x18A9 }, { 0x1920, 0x1922 }, { 0x1927, 0x1928 },
 108                { 0x1932, 0x1932 }, { 0x1939, 0x193B }, { 0x200B, 0x200F },
 109                { 0x202A, 0x202E }, { 0x2060, 0x2063 }, { 0x206A, 0x206F },
 110                { 0x20D0, 0x20EA }, { 0x302A, 0x302F }, { 0x3099, 0x309A },
 111                { 0xFB1E, 0xFB1E }, { 0xFE00, 0xFE0F }, { 0xFE20, 0xFE23 },
 112                { 0xFEFF, 0xFEFF }, { 0xFFF9, 0xFFFB }, { 0x1D167, 0x1D169 },
 113                { 0x1D173, 0x1D182 }, { 0x1D185, 0x1D18B },
 114                { 0x1D1AA, 0x1D1AD }, { 0xE0001, 0xE0001 },
 115                { 0xE0020, 0xE007F }, { 0xE0100, 0xE01EF }
 116        };
 117
 118        /* test for 8-bit control characters */
 119        if (ch == 0)
 120                return 0;
 121        if (ch < 32 || (ch >= 0x7f && ch < 0xa0))
 122                return -1;
 123
 124        /* binary search in table of non-spacing characters */
 125        if (bisearch(ch, combining, sizeof(combining)
 126                                / sizeof(struct interval) - 1))
 127                return 0;
 128
 129        /*
 130         * If we arrive here, ch is neither a combining nor a C0/C1
 131         * control character.
 132         */
 133
 134        return 1 +
 135                (ch >= 0x1100 &&
 136                    /* Hangul Jamo init. consonants */
 137                 (ch <= 0x115f ||
 138                  ch == 0x2329 || ch == 0x232a ||
 139                  /* CJK ... Yi */
 140                  (ch >= 0x2e80 && ch <= 0xa4cf &&
 141                   ch != 0x303f) ||
 142                  /* Hangul Syllables */
 143                  (ch >= 0xac00 && ch <= 0xd7a3) ||
 144                  /* CJK Compatibility Ideographs */
 145                  (ch >= 0xf900 && ch <= 0xfaff) ||
 146                  /* CJK Compatibility Forms */
 147                  (ch >= 0xfe30 && ch <= 0xfe6f) ||
 148                  /* Fullwidth Forms */
 149                  (ch >= 0xff00 && ch <= 0xff60) ||
 150                  (ch >= 0xffe0 && ch <= 0xffe6) ||
 151                  (ch >= 0x20000 && ch <= 0x2fffd) ||
 152                  (ch >= 0x30000 && ch <= 0x3fffd)));
 153}
 154
 155/*
 156 * This function returns the number of columns occupied by the character
 157 * pointed to by the variable start. The pointer is updated to point at
 158 * the next character. If it was not valid UTF-8, the pointer is set to NULL.
 159 */
 160int utf8_width(const char **start)
 161{
 162        unsigned char *s = (unsigned char *)*start;
 163        ucs_char_t ch;
 164
 165        if (*s < 0x80) {
 166                /* 0xxxxxxx */
 167                ch = *s;
 168                *start += 1;
 169        } else if ((s[0] & 0xe0) == 0xc0) {
 170                /* 110XXXXx 10xxxxxx */
 171                if ((s[1] & 0xc0) != 0x80 ||
 172                                /* overlong? */
 173                                (s[0] & 0xfe) == 0xc0)
 174                        goto invalid;
 175                ch = ((s[0] & 0x1f) << 6) | (s[1] & 0x3f);
 176                *start += 2;
 177        } else if ((s[0] & 0xf0) == 0xe0) {
 178                /* 1110XXXX 10Xxxxxx 10xxxxxx */
 179                if ((s[1] & 0xc0) != 0x80 ||
 180                                (s[2] & 0xc0) != 0x80 ||
 181                                /* overlong? */
 182                                (s[0] == 0xe0 && (s[1] & 0xe0) == 0x80) ||
 183                                /* surrogate? */
 184                                (s[0] == 0xed && (s[1] & 0xe0) == 0xa0) ||
 185                                /* U+FFFE or U+FFFF? */
 186                                (s[0] == 0xef && s[1] == 0xbf &&
 187                                 (s[2] & 0xfe) == 0xbe))
 188                        goto invalid;
 189                ch = ((s[0] & 0x0f) << 12) |
 190                        ((s[1] & 0x3f) << 6) | (s[2] & 0x3f);
 191                *start += 3;
 192        } else if ((s[0] & 0xf8) == 0xf0) {
 193                /* 11110XXX 10XXxxxx 10xxxxxx 10xxxxxx */
 194                if ((s[1] & 0xc0) != 0x80 ||
 195                                (s[2] & 0xc0) != 0x80 ||
 196                                (s[3] & 0xc0) != 0x80 ||
 197                                /* overlong? */
 198                                (s[0] == 0xf0 && (s[1] & 0xf0) == 0x80) ||
 199                                /* > U+10FFFF? */
 200                                (s[0] == 0xf4 && s[1] > 0x8f) || s[0] > 0xf4)
 201                        goto invalid;
 202                ch = ((s[0] & 0x07) << 18) | ((s[1] & 0x3f) << 12) |
 203                        ((s[2] & 0x3f) << 6) | (s[3] & 0x3f);
 204                *start += 4;
 205        } else {
 206invalid:
 207                *start = NULL;
 208                return 0;
 209        }
 210
 211        return git_wcwidth(ch);
 212}
 213
 214int is_utf8(const char *text)
 215{
 216        while (*text) {
 217                if (*text == '\n' || *text == '\t' || *text == '\r') {
 218                        text++;
 219                        continue;
 220                }
 221                utf8_width(&text);
 222                if (!text)
 223                        return 0;
 224        }
 225        return 1;
 226}
 227
 228static void print_spaces(int count)
 229{
 230        static const char s[] = "                    ";
 231        while (count >= sizeof(s)) {
 232                fwrite(s, sizeof(s) - 1, 1, stdout);
 233                count -= sizeof(s) - 1;
 234        }
 235        fwrite(s, count, 1, stdout);
 236}
 237
 238/*
 239 * Wrap the text, if necessary. The variable indent is the indent for the
 240 * first line, indent2 is the indent for all other lines.
 241 * If indent is negative, assume that already -indent columns have been
 242 * consumed (and no extra indent is necessary for the first line).
 243 */
 244int print_wrapped_text(const char *text, int indent, int indent2, int width)
 245{
 246        int w = indent, assume_utf8 = is_utf8(text);
 247        const char *bol = text, *space = NULL;
 248
 249        if (indent < 0) {
 250                w = -indent;
 251                space = text;
 252        }
 253
 254        for (;;) {
 255                char c = *text;
 256                if (!c || isspace(c)) {
 257                        if (w < width || !space) {
 258                                const char *start = bol;
 259                                if (space)
 260                                        start = space;
 261                                else
 262                                        print_spaces(indent);
 263                                fwrite(start, text - start, 1, stdout);
 264                                if (!c)
 265                                        return w;
 266                                else if (c == '\t')
 267                                        w |= 0x07;
 268                                space = text;
 269                                w++;
 270                                text++;
 271                        }
 272                        else {
 273                                putchar('\n');
 274                                text = bol = space + isspace(*space);
 275                                space = NULL;
 276                                w = indent = indent2;
 277                        }
 278                        continue;
 279                }
 280                if (assume_utf8)
 281                        w += utf8_width(&text);
 282                else {
 283                        w++;
 284                        text++;
 285                }
 286        }
 287}
 288
 289int is_encoding_utf8(const char *name)
 290{
 291        if (!name)
 292                return 1;
 293        if (!strcasecmp(name, "utf-8") || !strcasecmp(name, "utf8"))
 294                return 1;
 295        return 0;
 296}
 297
 298/*
 299 * Given a buffer and its encoding, return it re-encoded
 300 * with iconv.  If the conversion fails, returns NULL.
 301 */
 302#ifndef NO_ICONV
 303#ifdef OLD_ICONV
 304        typedef const char * iconv_ibp;
 305#else
 306        typedef char * iconv_ibp;
 307#endif
 308char *reencode_string(const char *in, const char *out_encoding, const char *in_encoding)
 309{
 310        iconv_t conv;
 311        size_t insz, outsz, outalloc;
 312        char *out, *outpos;
 313        iconv_ibp cp;
 314
 315        if (!in_encoding)
 316                return NULL;
 317        conv = iconv_open(out_encoding, in_encoding);
 318        if (conv == (iconv_t) -1)
 319                return NULL;
 320        insz = strlen(in);
 321        outsz = insz;
 322        outalloc = outsz + 1; /* for terminating NUL */
 323        out = xmalloc(outalloc);
 324        outpos = out;
 325        cp = (iconv_ibp)in;
 326
 327        while (1) {
 328                size_t cnt = iconv(conv, &cp, &insz, &outpos, &outsz);
 329
 330                if (cnt == -1) {
 331                        size_t sofar;
 332                        if (errno != E2BIG) {
 333                                free(out);
 334                                iconv_close(conv);
 335                                return NULL;
 336                        }
 337                        /* insz has remaining number of bytes.
 338                         * since we started outsz the same as insz,
 339                         * it is likely that insz is not enough for
 340                         * converting the rest.
 341                         */
 342                        sofar = outpos - out;
 343                        outalloc = sofar + insz * 2 + 32;
 344                        out = xrealloc(out, outalloc);
 345                        outpos = out + sofar;
 346                        outsz = outalloc - sofar - 1;
 347                }
 348                else {
 349                        *outpos = '\0';
 350                        break;
 351                }
 352        }
 353        iconv_close(conv);
 354        return out;
 355}
 356#endif