1/* Conversion UCS-4 to UTF-8. 2 Copyright (C) 2002, 2006-2007 Free Software Foundation, Inc. 3 Written by Bruno Haible <bruno@clisp.org>, 2002. 4 5 This program is free software: you can redistribute it and/or modify it 6 under the terms of the GNU General Public License as published 7 by the Free Software Foundation; either version 3 of the License, or 8 (at your option) any later version. 9 10 This program is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU General Public License 16 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 17 18#include <config.h> 19 20/* Specification. */ 21#include "unistr.h" 22 23int 24u8_uctomb_aux (uint8_t *s, ucs4_t uc, int n) 25{ 26 int count; 27 28 if (uc < 0x80) 29 /* The case n >= 1 is already handled by the caller. */ 30 return -2; 31 else if (uc < 0x800) 32 count = 2; 33 else if (uc < 0x10000) 34 { 35 if (uc < 0xd800 || uc >= 0xe000) 36 count = 3; 37 else 38 return -1; 39 } 40#if 0 41 else if (uc < 0x200000) 42 count = 4; 43 else if (uc < 0x4000000) 44 count = 5; 45 else if (uc <= 0x7fffffff) 46 count = 6; 47#else 48 else if (uc < 0x110000) 49 count = 4; 50#endif 51 else 52 return -1; 53 54 if (n < count) 55 return -2; 56 57 switch (count) /* note: code falls through cases! */ 58 { 59#if 0 60 case 6: s[5] = 0x80 | (uc & 0x3f); uc = uc >> 6; uc |= 0x4000000; 61 case 5: s[4] = 0x80 | (uc & 0x3f); uc = uc >> 6; uc |= 0x200000; 62#endif 63 case 4: s[3] = 0x80 | (uc & 0x3f); uc = uc >> 6; uc |= 0x10000; 64 case 3: s[2] = 0x80 | (uc & 0x3f); uc = uc >> 6; uc |= 0x800; 65 case 2: s[1] = 0x80 | (uc & 0x3f); uc = uc >> 6; uc |= 0xc0; 66 /*case 1:*/ s[0] = uc; 67 } 68 return count; 69} 70