commit 20f7a94e1890facb6e7f1a12acf4cf5e1e8de977
from: Omar Polo <op@omarpolo.com>
date: Fri Oct 07 07:57:31 2022 UTC

work around missing LOGIN_NAME_MAX

Both Linux and OpenBSD have LOGIN_NAME_MAX available when including
limits.h, FreeBSD, Darwin and possibly others don't.

FreeBSD (and maybe Darwin) have MAXLOGNAME, so try to use that if
available.  Otherwise use _POSIX_LOGIN_NAME_MAX, but only has a fallback
since it has a lower value (9 at the time of writing).

If everything fails, use 32 which is what OpenBSD use by default;
OpenSMTPd also defaults to it.

See also github issue #1

commit - a02f394431fcc473fb8290b17036d1275d2ccf0a
commit + 20f7a94e1890facb6e7f1a12acf4cf5e1e8de977
blob - f076107c77bf22a64cbe48841f2a93e082efa10a
blob + d6f802df3d1937acb06856cd8af71350a4b41fda
--- kamid/kamid.h
+++ kamid/kamid.h
@@ -21,6 +21,17 @@
 #include <stdint.h>
 #include <tls.h>
 
+/* Linux and OpenBSD have LOGIN_NAME_MAX, FreeBSD MAXLOGNAME. */
+#ifndef LOGIN_NAME_MAX
+# if defined(MAXLOGNAME)
+#  define LOGIN_NAME_MAX MAXLOGNAME
+# elif defined(_POSIX_LOGIN_NAME_MAX)
+#  define LOGIN_NAME_MAX _POSIX_LOGIN_NAME_MAX
+# else
+#  define LOGIN_NAME_MAX 32
+# endif
+#endif
+
 /* TODO: make these customizable */
 #define KD_CONF_FILE		"/etc/kamid.conf"
 #define KD_USER			"_kamid"