argp-standalone/strcasecmp.c


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/* strcasecmp.c
 *
 */

/* Written by Niels Möller <nisse@lysator.liu.se>
 *
 * This file is hereby placed in the public domain.
 */

#include <ctype.h>
int strcasecmp(const char *, const char *);

int strcasecmp(const char *s1, const char *s2)
{
  unsigned i;
  
  for (i = 0; s1[i] && s2[i]; i++)
    {
      unsigned char c1 = tolower( (unsigned char) s1[i]);
      unsigned char c2 = tolower( (unsigned char) s2[i]);

      if (c1 < c2)
	return -1;
      else if (c1 > c2)
	return 1;
    }

  return !s2[i] - !s1[i];	
}