libc/newlib/libc/string/strcasecmp_l.c

55 lines
1.2 KiB
C

/*
FUNCTION
<<strcasecmp_l>>---case-insensitive character string compare
INDEX
strcasecmp_l
SYNOPSIS
#include <strings.h>
int strcasecmp_l(const char *<[a]>, const char *<[b]>,
locale_t <[locale]>);
DESCRIPTION
<<strcasecmp_l>> compares the string at <[a]> to
the string at <[b]> in a case-insensitive manner.
if <[locale]> is LC_GLOBAL_LOCALE or not a valid locale object, the
behaviour is undefined.
RETURNS
If <<*<[a]>>> sorts lexicographically after <<*<[b]>>> (after
both are converted to lowercase), <<strcasecmp_l>> returns a
number greater than zero. If the two strings match,
<<strcasecmp_l>> returns zero. If <<*<[a]>>> sorts
lexicographically before <<*<[b]>>>, <<strcasecmp_l>> returns a
number less than zero.
PORTABILITY
<<strcasecmp_l>> is POSIX-1.2008.
<<strcasecmp_l>> requires no supporting OS subroutines. It uses
tolower_l() from elsewhere in this library.
QUICKREF
strcasecmp_l
*/
#include <strings.h>
#include <ctype.h>
int
strcasecmp_l (const char *s1, const char *s2, struct __locale_t *locale)
{
int d = 0;
for ( ; ; )
{
const int c1 = tolower_l (*s1++, locale);
const int c2 = tolower_l (*s2++, locale);
if (((d = c1 - c2) != 0) || (c2 == '\0'))
break;
}
return d;
}