| /* |
| * Copyright (C) 1999-2001, 2008 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 { |
| conv->istate = state; |
| return RET_SHIFT_ILSEQ(count); |
| } |
| } |
| 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; |
| } |