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Diffstat (limited to 'lib/memcasecmp.c')
-rw-r--r-- | lib/memcasecmp.c | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/lib/memcasecmp.c b/lib/memcasecmp.c new file mode 100644 index 0000000..cddf76a --- /dev/null +++ b/lib/memcasecmp.c @@ -0,0 +1,49 @@ +/* Case-insensitive buffer comparator. + Copyright (C) 1996, 1997, 2000, 2003, 2006 Free Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software Foundation, + Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ + +/* Written by Jim Meyering. */ + +#include <config.h> + +#include "memcasecmp.h" + +#include <ctype.h> +#include <limits.h> + +/* Like memcmp, but ignore differences in case. + Convert to upper case (not lower) before comparing so that + join -i works with sort -f. */ + +int +memcasecmp (const void *vs1, const void *vs2, size_t n) +{ + size_t i; + char const *s1 = vs1; + char const *s2 = vs2; + for (i = 0; i < n; i++) + { + unsigned char u1 = s1[i]; + unsigned char u2 = s2[i]; + int U1 = toupper (u1); + int U2 = toupper (u2); + int diff = (UCHAR_MAX <= INT_MAX ? U1 - U2 + : U1 < U2 ? -1 : U2 < U1); + if (diff) + return diff; + } + return 0; +} |