1 /* 2 * Copyright (C) 1999-2001 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 * UCS-4 23 */ 24 25 /* Here we accept FFFE0000/0000FEFF marks as endianness indicators everywhere 26 in the stream, not just at the beginning. The default is big-endian. */ 27 /* The state is 0 if big-endian, 1 if little-endian. */ 28 static int 29 ucs4_mbtowc (conv_t conv, ucs4_t *pwc, const unsigned char *s, int n) 30 { 31 state_t state = conv->istate; 32 int count = 0; 33 for (; n >= 4;) { 34 ucs4_t wc = (state 35 ? s[0] + (s[1] << 8) + (s[2] << 16) + (s[3] << 24) 36 : (s[0] << 24) + (s[1] << 16) + (s[2] << 8) + s[3]); 37 s += 4; n -= 4; count += 4; 38 if (wc == 0x0000feff) { 39 } else if (wc == 0xfffe0000u) { 40 state ^= 1; 41 } else if (wc <= 0x7fffffff) { 42 *pwc = wc; 43 conv->istate = state; 44 return count; 45 } else 46 return RET_ILSEQ; 47 } 48 conv->istate = state; 49 return RET_TOOFEW(count); 50 } 51 52 /* But we output UCS-4 in big-endian order, without byte-order mark. */ 53 static int 54 ucs4_wctomb (conv_t conv, unsigned char *r, ucs4_t wc, int n) 55 { 56 if (wc <= 0x7fffffff) { 57 if (n >= 4) { 58 r[0] = (unsigned char) (wc >> 24); 59 r[1] = (unsigned char) (wc >> 16); 60 r[2] = (unsigned char) (wc >> 8); 61 r[3] = (unsigned char) wc; 62 return 4; 63 } else 64 return RET_TOOSMALL; 65 } else 66 return RET_ILUNI; 67 } 68