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#include "dietfeatures.h"
#include <string.h>
#ifdef WANT_NON_COMPLIANT_STRNCAT
/* this implementation is not standards compliant.
* the standard says that strncat(dest,"foobar",3) should write 'f', 'o'
* and 'o'. The programmer is then expected to overwrite the last byte
* with '\0', which is often forgotten. This implementation makes sure
* the last written bytes is always '\0'. */
#endif
/* gcc is broken and has a non-SUSv2 compliant internal prototype.
* This causes it to warn about a type mismatch here. Ignore it. */
char *strncat(char *s, const char *t, size_t n) {
char *dest=s;
register char *max;
s+=strlen(s);
#ifdef WANT_NON_COMPLIANT_STRNCAT
if ((max=s+n-1)<=s) goto fini;
#else
if ((max=s+n)==s) goto fini;
#endif
for (;;) {
if (!(*s = *t)) break; if (++s==max) break; ++t;
#ifndef WANT_SMALL_STRING_ROUTINES
if (!(*s = *t)) break; if (++s==max) break; ++t;
if (!(*s = *t)) break; if (++s==max) break; ++t;
if (!(*s = *t)) break; if (++s==max) break; ++t;
#endif
}
*s=0;
fini:
return dest;
}
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