Add llabs() implementation.

configure.ac

@@ -1717,6 +1717,7 @@ AC_CHECK_FUNCS([ \
 	inet_ntoa \
 	inet_ntop \
 	innetgr \
+	llabs \
 	login_getcapbool \
 	md5_crypt \
 	memmove \

openbsd-compat/bsd-misc.c

@@ -301,3 +301,11 @@ mbtowc(wchar_t *pwc, const char *s, size_t n)
 	return 1;
 }
 #endif
+
+#ifndef HAVE_LLABS
+long long
+llabs(long long j)
+{
+	return (j < 0 ? -j : j);
+}
+#endif

openbsd-compat/bsd-misc.h

@@ -135,4 +135,8 @@ void errx(int, const char *, ...) __attribute__((format(printf, 2, 3)));
 void warn(const char *, ...) __attribute__((format(printf, 1, 2)));
 #endif
 
+#ifndef HAVE_LLABS
+long long llabs(long long);
+#endif
+
 #endif /* _BSD_MISC_H */