getmntent: fix memory corruption w/blank lines [BZ #18887]
[glibc.git] / wcsmbs / wcsncmp.c
blob4de2ca8c0a5abd960cef4b5fc13cc810fa02a854
1 /* Copyright (C) 1995-2015 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library 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.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <http://www.gnu.org/licenses/>. */
19 #include <wchar.h>
21 #ifndef WCSNCMP
22 # define WCSNCMP wcsncmp
23 #endif
25 /* Compare no more than N characters of S1 and S2,
26 returning less than, equal to or greater than zero
27 if S1 is lexicographically less than, equal to or
28 greater than S2. */
29 int
30 WCSNCMP (s1, s2, n)
31 const wchar_t *s1;
32 const wchar_t *s2;
33 size_t n;
35 wchar_t c1 = L'\0';
36 wchar_t c2 = L'\0';
38 if (n >= 4)
40 size_t n4 = n >> 2;
43 c1 = *s1++;
44 c2 = *s2++;
45 if (c1 == L'\0' || c1 != c2)
46 return c1 > c2 ? 1 : (c1 < c2 ? -1 : 0);
47 c1 = *s1++;
48 c2 = *s2++;
49 if (c1 == L'\0' || c1 != c2)
50 return c1 > c2 ? 1 : (c1 < c2 ? -1 : 0);
51 c1 = *s1++;
52 c2 = *s2++;
53 if (c1 == L'\0' || c1 != c2)
54 return c1 > c2 ? 1 : (c1 < c2 ? -1 : 0);
55 c1 = *s1++;
56 c2 = *s2++;
57 if (c1 == L'\0' || c1 != c2)
58 return c1 > c2 ? 1 : (c1 < c2 ? -1 : 0);
59 } while (--n4 > 0);
60 n &= 3;
63 while (n > 0)
65 c1 = *s1++;
66 c2 = *s2++;
67 if (c1 == L'\0' || c1 != c2)
68 return c1 > c2 ? 1 : (c1 < c2 ? -1 : 0);
69 n--;
72 return 0;