/* * Copyright (C) 1999-2001 Free Software Foundation, Inc. * This file is part of the GNU LIBICONV Library. * * The GNU LIBICONV Library is free software; you can redistribute it * and/or modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * The GNU LIBICONV Library is distributed in the hope that it will be * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with the GNU LIBICONV Library; see the file COPYING.LIB. * If not, write to the Free Software Foundation, Inc., 51 Franklin Street, * Fifth Floor, Boston, MA 02110-1301, USA. */ /* * UTF-32 */ /* Specification: Unicode 3.1 Standard Annex #19 */ /* Here we accept FFFE0000/0000FEFF marks as endianness indicators everywhere in the stream, not just at the beginning. (This is contrary to what #19 D36c specifies, but it allows concatenation of byte sequences to work flawlessly, while disagreeing with #19 behaviour only for strings containing U+FEFF characters, which is quite rare.) The default is big-endian. */ /* The state is 0 if big-endian, 1 if little-endian. */ static int utf32_mbtowc (conv_t conv, ucs4_t *pwc, const unsigned char *s, int n) { state_t state = conv->istate; int count = 0; for (; n >= 4;) { ucs4_t wc = (state ? s[0] + (s[1] << 8) + (s[2] << 16) + (s[3] << 24) : (s[0] << 24) + (s[1] << 16) + (s[2] << 8) + s[3]); count += 4; if (wc == 0x0000feff) { } else if (wc == 0xfffe0000u) { state ^= 1; } else { if (wc < 0x110000 && !(wc >= 0xd800 && wc < 0xe000)) { *pwc = wc; conv->istate = state; return count; } else return RET_ILSEQ; } s += 4; n -= 4; } conv->istate = state; return RET_TOOFEW(count); } /* We output UTF-32 in big-endian order, with byte-order mark. */ /* The state is 0 at the beginning, 1 after the BOM has been written. */ static int utf32_wctomb (conv_t conv, unsigned char *r, ucs4_t wc, int n) { if (wc < 0x110000 && !(wc >= 0xd800 && wc < 0xe000)) { int count = 0; if (!conv->ostate) { if (n >= 4) { r[0] = 0x00; r[1] = 0x00; r[2] = 0xFE; r[3] = 0xFF; r += 4; n -= 4; count += 4; } else return RET_TOOSMALL; } if (wc < 0x110000) { if (n >= 4) { r[0] = 0; r[1] = (unsigned char) (wc >> 16); r[2] = (unsigned char) (wc >> 8); r[3] = (unsigned char) wc; conv->ostate = 1; return count+4; } else return RET_TOOSMALL; } } return RET_ILUNI; }