| DRC | 2ff39b8 | 2011-07-28 08:38:59 +0000 | [diff] [blame] | 1 | /* $XFree86: xc/lib/X11/lcUniConv/utf8.h,v 1.3 2000/11/28 18:50:07 dawes Exp $ */ |
| 2 | |
| 3 | /* |
| 4 | * UTF-8 |
| 5 | */ |
| 6 | |
| 7 | /* Specification: RFC 2279 */ |
| 8 | |
| 9 | static int |
| 10 | utf8_mbtowc (conv_t conv, ucs4_t *pwc, const unsigned char *s, int n) |
| 11 | { |
| 12 | unsigned char c = s[0]; |
| 13 | |
| 14 | if (c < 0x80) { |
| 15 | *pwc = c; |
| 16 | return 1; |
| 17 | } else if (c < 0xc2) { |
| 18 | return RET_ILSEQ; |
| 19 | } else if (c < 0xe0) { |
| 20 | if (n < 2) |
| 21 | return RET_TOOFEW(0); |
| 22 | if (!((s[1] ^ 0x80) < 0x40)) |
| 23 | return RET_ILSEQ; |
| 24 | *pwc = ((ucs4_t) (c & 0x1f) << 6) |
| 25 | | (ucs4_t) (s[1] ^ 0x80); |
| 26 | return 2; |
| 27 | } else if (c < 0xf0) { |
| 28 | if (n < 3) |
| 29 | return RET_TOOFEW(0); |
| 30 | if (!((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40 |
| 31 | && (c >= 0xe1 || s[1] >= 0xa0))) |
| 32 | return RET_ILSEQ; |
| 33 | *pwc = ((ucs4_t) (c & 0x0f) << 12) |
| 34 | | ((ucs4_t) (s[1] ^ 0x80) << 6) |
| 35 | | (ucs4_t) (s[2] ^ 0x80); |
| 36 | return 3; |
| 37 | } else if (c < 0xf8) { |
| 38 | if (n < 4) |
| 39 | return RET_TOOFEW(0); |
| 40 | if (!((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40 |
| 41 | && (s[3] ^ 0x80) < 0x40 |
| 42 | && (c >= 0xf1 || s[1] >= 0x90))) |
| 43 | return RET_ILSEQ; |
| 44 | *pwc = ((ucs4_t) (c & 0x07) << 18) |
| 45 | | ((ucs4_t) (s[1] ^ 0x80) << 12) |
| 46 | | ((ucs4_t) (s[2] ^ 0x80) << 6) |
| 47 | | (ucs4_t) (s[3] ^ 0x80); |
| 48 | return 4; |
| 49 | } else if (c < 0xfc) { |
| 50 | if (n < 5) |
| 51 | return RET_TOOFEW(0); |
| 52 | if (!((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40 |
| 53 | && (s[3] ^ 0x80) < 0x40 && (s[4] ^ 0x80) < 0x40 |
| 54 | && (c >= 0xf9 || s[1] >= 0x88))) |
| 55 | return RET_ILSEQ; |
| 56 | *pwc = ((ucs4_t) (c & 0x03) << 24) |
| 57 | | ((ucs4_t) (s[1] ^ 0x80) << 18) |
| 58 | | ((ucs4_t) (s[2] ^ 0x80) << 12) |
| 59 | | ((ucs4_t) (s[3] ^ 0x80) << 6) |
| 60 | | (ucs4_t) (s[4] ^ 0x80); |
| 61 | return 5; |
| 62 | } else if (c < 0xfe) { |
| 63 | if (n < 6) |
| 64 | return RET_TOOFEW(0); |
| 65 | if (!((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40 |
| 66 | && (s[3] ^ 0x80) < 0x40 && (s[4] ^ 0x80) < 0x40 |
| 67 | && (s[5] ^ 0x80) < 0x40 |
| 68 | && (c >= 0xfd || s[1] >= 0x84))) |
| 69 | return RET_ILSEQ; |
| 70 | *pwc = ((ucs4_t) (c & 0x01) << 30) |
| 71 | | ((ucs4_t) (s[1] ^ 0x80) << 24) |
| 72 | | ((ucs4_t) (s[2] ^ 0x80) << 18) |
| 73 | | ((ucs4_t) (s[3] ^ 0x80) << 12) |
| 74 | | ((ucs4_t) (s[4] ^ 0x80) << 6) |
| 75 | | (ucs4_t) (s[5] ^ 0x80); |
| 76 | return 6; |
| 77 | } else |
| 78 | return RET_ILSEQ; |
| 79 | } |
| 80 | |
| 81 | static int |
| 82 | utf8_wctomb (conv_t conv, unsigned char *r, ucs4_t wc, int n) /* n == 0 is acceptable */ |
| 83 | { |
| 84 | int count; |
| 85 | if (wc < 0x80) |
| 86 | count = 1; |
| 87 | else if (wc < 0x800) |
| 88 | count = 2; |
| 89 | else if (wc < 0x10000) |
| 90 | count = 3; |
| 91 | else if (wc < 0x200000) |
| 92 | count = 4; |
| 93 | else if (wc < 0x4000000) |
| 94 | count = 5; |
| 95 | else if (wc <= 0x7fffffff) |
| 96 | count = 6; |
| 97 | else |
| 98 | return RET_ILSEQ; |
| 99 | if (n < count) |
| 100 | return RET_TOOSMALL; |
| 101 | switch (count) { /* note: code falls through cases! */ |
| 102 | case 6: r[5] = 0x80 | (wc & 0x3f); wc = wc >> 6; wc |= 0x4000000; |
| 103 | case 5: r[4] = 0x80 | (wc & 0x3f); wc = wc >> 6; wc |= 0x200000; |
| 104 | case 4: r[3] = 0x80 | (wc & 0x3f); wc = wc >> 6; wc |= 0x10000; |
| 105 | case 3: r[2] = 0x80 | (wc & 0x3f); wc = wc >> 6; wc |= 0x800; |
| 106 | case 2: r[1] = 0x80 | (wc & 0x3f); wc = wc >> 6; wc |= 0xc0; |
| 107 | case 1: r[0] = wc; |
| 108 | } |
| 109 | return count; |
| 110 | } |