1 /* 2 * Copyright (C) 1999-2001, 2004 Free Software Foundation, Inc. 3 * This file is part of the GNU LIBICONV Library. 4 * 5 * The GNU LIBICONV Library is free software; you can redistribute it 6 * and/or modify it under the terms of the GNU Library General Public 7 * License as published by the Free Software Foundation; either version 2 8 * of the License, or (at your option) any later version. 9 * 10 * The GNU LIBICONV Library is distributed in the hope that it will be 11 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 * Library General Public License for more details. 14 * 15 * You should have received a copy of the GNU Library General Public 16 * License along with the GNU LIBICONV Library; see the file COPYING.LIB. 17 * If not, write to the Free Software Foundation, Inc., 51 Franklin Street, 18 * Fifth Floor, Boston, MA 02110-1301, USA. 19 */ 20 21 /* 22 * UTF-8 23 */ 24 25 /* Specification: RFC 3629 */ 26 27 static int 28 utf8_mbtowc (conv_t conv, ucs4_t *pwc, const unsigned char *s, int n) 29 { 30 unsigned char c = s[0]; 31 32 if (c < 0x80) { 33 *pwc = c; 34 return 1; 35 } else if (c < 0xc2) { 36 return RET_ILSEQ; 37 } else if (c < 0xe0) { 38 if (n < 2) 39 return RET_TOOFEW(0); 40 if (!((s[1] ^ 0x80) < 0x40)) 41 return RET_ILSEQ; 42 *pwc = ((ucs4_t) (c & 0x1f) << 6) 43 | (ucs4_t) (s[1] ^ 0x80); 44 return 2; 45 } else if (c < 0xf0) { 46 if (n < 3) 47 return RET_TOOFEW(0); 48 if (!((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40 49 && (c >= 0xe1 || s[1] >= 0xa0))) 50 return RET_ILSEQ; 51 *pwc = ((ucs4_t) (c & 0x0f) << 12) 52 | ((ucs4_t) (s[1] ^ 0x80) << 6) 53 | (ucs4_t) (s[2] ^ 0x80); 54 return 3; 55 } else if (c < 0xf8 && sizeof(ucs4_t)*8 >= 32) { 56 if (n < 4) 57 return RET_TOOFEW(0); 58 if (!((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40 59 && (s[3] ^ 0x80) < 0x40 60 && (c >= 0xf1 || s[1] >= 0x90))) 61 return RET_ILSEQ; 62 *pwc = ((ucs4_t) (c & 0x07) << 18) 63 | ((ucs4_t) (s[1] ^ 0x80) << 12) 64 | ((ucs4_t) (s[2] ^ 0x80) << 6) 65 | (ucs4_t) (s[3] ^ 0x80); 66 return 4; 67 } else if (c < 0xfc && sizeof(ucs4_t)*8 >= 32) { 68 if (n < 5) 69 return RET_TOOFEW(0); 70 if (!((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40 71 && (s[3] ^ 0x80) < 0x40 && (s[4] ^ 0x80) < 0x40 72 && (c >= 0xf9 || s[1] >= 0x88))) 73 return RET_ILSEQ; 74 *pwc = ((ucs4_t) (c & 0x03) << 24) 75 | ((ucs4_t) (s[1] ^ 0x80) << 18) 76 | ((ucs4_t) (s[2] ^ 0x80) << 12) 77 | ((ucs4_t) (s[3] ^ 0x80) << 6) 78 | (ucs4_t) (s[4] ^ 0x80); 79 return 5; 80 } else if (c < 0xfe && sizeof(ucs4_t)*8 >= 32) { 81 if (n < 6) 82 return RET_TOOFEW(0); 83 if (!((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40 84 && (s[3] ^ 0x80) < 0x40 && (s[4] ^ 0x80) < 0x40 85 && (s[5] ^ 0x80) < 0x40 86 && (c >= 0xfd || s[1] >= 0x84))) 87 return RET_ILSEQ; 88 *pwc = ((ucs4_t) (c & 0x01) << 30) 89 | ((ucs4_t) (s[1] ^ 0x80) << 24) 90 | ((ucs4_t) (s[2] ^ 0x80) << 18) 91 | ((ucs4_t) (s[3] ^ 0x80) << 12) 92 | ((ucs4_t) (s[4] ^ 0x80) << 6) 93 | (ucs4_t) (s[5] ^ 0x80); 94 return 6; 95 } else 96 return RET_ILSEQ; 97 } 98 99 static int 100 utf8_wctomb (conv_t conv, unsigned char *r, ucs4_t wc, int n) /* n == 0 is acceptable */ 101 { 102 int count; 103 if (wc < 0x80) 104 count = 1; 105 else if (wc < 0x800) 106 count = 2; 107 else if (wc < 0x10000) 108 count = 3; 109 else if (wc < 0x200000) 110 count = 4; 111 else if (wc < 0x4000000) 112 count = 5; 113 else if (wc <= 0x7fffffff) 114 count = 6; 115 else 116 return RET_ILUNI; 117 if (n < count) 118 return RET_TOOSMALL; 119 switch (count) { /* note: code falls through cases! */ 120 case 6: r[5] = 0x80 | (wc & 0x3f); wc = wc >> 6; wc |= 0x4000000; 121 case 5: r[4] = 0x80 | (wc & 0x3f); wc = wc >> 6; wc |= 0x200000; 122 case 4: r[3] = 0x80 | (wc & 0x3f); wc = wc >> 6; wc |= 0x10000; 123 case 3: r[2] = 0x80 | (wc & 0x3f); wc = wc >> 6; wc |= 0x800; 124 case 2: r[1] = 0x80 | (wc & 0x3f); wc = wc >> 6; wc |= 0xc0; 125 case 1: r[0] = wc; 126 } 127 return count; 128 } 129