1 /* Conversion UCS-4 to UTF-16.
2 Copyright (C) 2002, 2006-2007, 2009-2014 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 Lesser 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 Lesser 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
23 int
u16_uctomb_aux(uint16_t * s,ucs4_t uc,int n)24 u16_uctomb_aux (uint16_t *s, ucs4_t uc, int n)
25 {
26 if (uc < 0xd800)
27 {
28 /* The case n >= 1 is already handled by the caller. */
29 }
30 else if (uc < 0x10000)
31 {
32 if (uc >= 0xe000)
33 {
34 if (n >= 1)
35 {
36 s[0] = uc;
37 return 1;
38 }
39 }
40 else
41 return -1;
42 }
43 else
44 {
45 if (uc < 0x110000)
46 {
47 if (n >= 2)
48 {
49 s[0] = 0xd800 + ((uc - 0x10000) >> 10);
50 s[1] = 0xdc00 + ((uc - 0x10000) & 0x3ff);
51 return 2;
52 }
53 }
54 else
55 return -1;
56 }
57 return -2;
58 }
59