1 /* Look at first character in UTF-16 string. 2 Copyright (C) 1999-2000, 2002, 2006-2007, 2009-2021 Free Software 3 Foundation, Inc. 4 Written by Bruno Haible <bruno@clisp.org>, 2002. 5 6 This file is free software. 7 It is dual-licensed under "the GNU LGPLv3+ or the GNU GPLv2+". 8 You can redistribute it and/or modify it under either 9 - the terms of the GNU Lesser General Public License as published 10 by the Free Software Foundation; either version 3, or (at your 11 option) any later version, or 12 - the terms of the GNU General Public License as published by the 13 Free Software Foundation; either version 2, or (at your option) 14 any later version, or 15 - the same dual license "the GNU LGPLv3+ or the GNU GPLv2+". 16 17 This file is distributed in the hope that it will be useful, 18 but WITHOUT ANY WARRANTY; without even the implied warranty of 19 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 20 Lesser General Public License and the GNU General Public License 21 for more details. 22 23 You should have received a copy of the GNU Lesser General Public 24 License and of the GNU General Public License along with this 25 program. If not, see <https://www.gnu.org/licenses/>. */ 26 27 #include <config.h> 28 29 /* Specification. */ 30 #include "unistr.h" 31 32 int 33 u16_strmbtouc (ucs4_t *puc, const uint16_t *s) /* */ 34 { 35 /* Keep in sync with unistr.h and u16-mbtouc-aux.c. */ 36 uint16_t c = *s; 37 38 if (c < 0xd800 || c >= 0xe000) 39 { 40 *puc = c; 41 return (c != 0 ? 1 : 0); 42 } 43 if (c < 0xdc00) 44 { 45 if (s[1] >= 0xdc00 && s[1] < 0xe000) 46 { 47 *puc = 0x10000 + ((c - 0xd800) << 10) + (s[1] - 0xdc00); 48 return 2; 49 } 50 } 51 /* invalid or incomplete multibyte character */ 52 return -1; 53 }