Replace libmissing.la with portable libobj dir

Commit 8e2b75c removed getopt from libmissing since modern systems
include getopt_long().  That change resulted in libmissing being
empty on macOS, and macOS "ar" requires at least one file to be added.

Replace "libmissing.la" with the autoconf libobj directory "portable"
(AC_CONFIG_LIBOBJ_DIR) as the directory for AC_REPLACE_FUNCS
replacements.  Move "src/libmissing/" to "portable/".  Remove
"libmissing" from SUBDIRS.  Update "Makefile.am" CPPFLAGS and LDADD
accordingly.

Define the automake "subdir-objects" option since "$(LIBOBJS)" cannot
be used outside of "portable" if "subdir-objects" is not set.

Also, rename the macro def INET_NTOP_H to MUNGE_INET_NTOP_H.

Reference:
- https://www.eyrie.org/~eagle/notes/style/build.html
- https://www.gnu.org/software/automake/manual/html_node/List-of-Automake-options.html

https://github.com/dun/munge/issues/141
https://github.com/dun/munge/commit/fa5849f9313e2b0a656b5177b08088f94bfaab68
--- Make-inc.mk.orig
+++ Make-inc.mk
@@ -6,7 +6,6 @@
 # Dependencies to ensure libraries get rebuilt.
 #
 $(top_builddir)/src/libcommon/libcommon.la \
-$(top_builddir)/src/libmissing/libmissing.la \
 $(top_builddir)/src/libmunge/libmunge.la \
 $(top_builddir)/src/libtap/libtap.la \
 : force-dependency-check
--- Makefile.am.orig
+++ Makefile.am
@@ -35,6 +35,9 @@ EXTRA_DIST = \
 	build-aux/gen-version \
 	build-aux/tap-driver.sh \
 	doc \
+	portable/inet_ntop.h \
+	portable/strlcat.h \
+	portable/strlcpy.h \
 	$(TEMPLATE_FILES) \
 	# End of EXTRA_DIST
 
@@ -65,7 +68,6 @@ MAINTAINERCLEANFILES = \
 	src/Makefile.in \
 	src/etc/Makefile.in \
 	src/libcommon/Makefile.in \
-	src/libmissing/Makefile.in \
 	src/libmunge/Makefile.in \
 	src/munge/Makefile.in \
 	src/munged/Makefile.in \
--- configure.ac.orig
+++ configure.ac
@@ -12,6 +12,7 @@ AC_SUBST([DATE], m4_esyscmd([build-aux/gen-date]))
 
 AC_CONFIG_AUX_DIR([build-aux])
 AC_CONFIG_HEADERS([config.h])
+AC_CONFIG_LIBOBJ_DIR([portable])
 AC_CONFIG_MACRO_DIR([m4])
 AC_CONFIG_SRCDIR([src/libmunge/munge.h])
 AC_REQUIRE_AUX_FILE([tap-driver.sh])
@@ -25,7 +26,7 @@ X_AC_WITH_LOGROTATEDDIR
 X_AC_WITH_PKGCONFIGDIR
 X_AC_HUMOR
 
-AM_INIT_AUTOMAKE([1.12 foreign dist-xz no-dist-gzip])
+AM_INIT_AUTOMAKE([1.12 foreign dist-xz no-dist-gzip subdir-objects])
 AM_MAINTAINER_MODE
 AM_SILENT_RULES([yes])
 AC_USE_SYSTEM_EXTENSIONS
@@ -121,7 +122,6 @@ AC_CONFIG_FILES( \
   src/common/Makefile \
   src/etc/Makefile \
   src/libcommon/Makefile \
-  src/libmissing/Makefile \
   src/libmunge/Makefile \
   src/libtap/Makefile \
   src/munge/Makefile \
--- src/libmissing/inet_ntop.h.orig
+++ portable/inet_ntop.h
@@ -25,22 +25,22 @@
  *****************************************************************************/
 
 
-#ifndef INET_NTOP_H
-#define INET_NTOP_H
+#ifndef MUNGE_INET_NTOP_H
+#define MUNGE_INET_NTOP_H
 
 #if HAVE_CONFIG_H
-#  include "config.h"
+#include "config.h"
 #endif /* HAVE_CONFIG_H */
 
 #ifndef INET_ADDRSTRLEN
-#  define INET_ADDRSTRLEN 16
+#define INET_ADDRSTRLEN 16
 #endif /* !INET_ADDRSTRLEN */
 
 #if HAVE_INET_NTOP
-#  include <arpa/inet.h>
+#include <arpa/inet.h>
 #else  /* !HAVE_INET_NTOP */
-#  include <sys/socket.h>
+#include <sys/socket.h>
 const char *inet_ntop (int af, const void *src, char *dst, socklen_t cnt);
 #endif /* !HAVE_INET_NTOP */
 
-#endif /* !INET_NTOP_H */
+#endif /* !MUNGE_INET_NTOP_H */
--- src/libmissing/strlcat.h.orig
+++ portable/strlcat.h
@@ -1,8 +1,13 @@
+#ifndef MUNGE_STRLCAT_H
+#define MUNGE_STRLCAT_H
+
 #if HAVE_CONFIG_H
-#  include "config.h"
+#include "config.h"
 #endif /* HAVE_CONFIG_H */
 
-#if !HAVE_STRLCAT
+#if HAVE_STRLCAT
+#include <string.h>
+#else /* !HAVE_STRLCAT */
 size_t strlcat(char *dst, const char *src, size_t siz);
 /*
  *  Appends src to string dst of size siz (unlike strncat, siz is the
@@ -12,3 +17,5 @@ size_t strlcat(char *dst, const char *src, size_t siz);
  *  If retval >= siz, truncation occurred.
  */
 #endif /* !HAVE_STRLCAT */
+
+#endif /* !MUNGE_STRLCAT_H */
--- src/libmissing/strlcpy.h.orig
+++ portable/strlcpy.h
@@ -1,8 +1,13 @@
+#ifndef MUNGE_STRLCPY_H
+#define MUNGE_STRLCPY_H
+
 #if HAVE_CONFIG_H
-#  include "config.h"
+#include "config.h"
 #endif /* HAVE_CONFIG_H */
 
-#if !HAVE_STRLCPY
+#if HAVE_STRLCPY
+#include <string.h>
+#else /* !HAVE_STRLCPY */
 size_t strlcpy(char *dst, const char *src, size_t siz);
 /*
  *  Copy src to string dst of size siz.  At most siz-1 characters
@@ -10,3 +15,5 @@ size_t strlcpy(char *dst, const char *src, size_t siz);
  *  Returns strlen(src); if retval >= siz, truncation occurred.
  */
 #endif /* !HAVE_STRLCPY */
+
+#endif /* !MUNGE_STRLCPY_H */
--- src/Makefile.am.orig
+++ src/Makefile.am
@@ -9,7 +9,6 @@ SUBDIRS = \
 	common \
 	etc \
 	libcommon \
-	libmissing \
 	libmunge \
 	libtap \
 	munge \
--- src/munge/Makefile.am.orig
+++ src/munge/Makefile.am
@@ -41,13 +41,11 @@ bin_PROGRAMS = \
 munge_CPPFLAGS = \
 	-I$(top_srcdir)/src/common \
 	-I$(top_srcdir)/src/libcommon \
-	-I$(top_srcdir)/src/libmissing \
 	-I$(top_srcdir)/src/libmunge \
 	# End of munge_CPPFLAGS
 
 munge_LDADD = \
 	$(top_builddir)/src/libcommon/libcommon.la \
-	$(top_builddir)/src/libmissing/libmissing.la \
 	$(top_builddir)/src/libmunge/libmunge.la \
 	# End of munge_LDADD
 
@@ -69,13 +67,11 @@ remunge_CPPFLAGS = \
 	-DWITH_PTHREADS \
 	-I$(top_srcdir)/src/common \
 	-I$(top_srcdir)/src/libcommon \
-	-I$(top_srcdir)/src/libmissing \
 	-I$(top_srcdir)/src/libmunge \
 	# End of remunge_CPPFLAGS
 
 remunge_LDADD = \
 	$(top_builddir)/src/libcommon/libcommon.la \
-	$(top_builddir)/src/libmissing/libmissing.la \
 	$(top_builddir)/src/libmunge/libmunge.la \
 	$(LIBPTHREAD) \
 	# End of remunge_LDADD
@@ -93,15 +89,15 @@ remunge_SOURCES = \
 	# End of remunge_SOURCES
 
 unmunge_CPPFLAGS = \
+	-I$(top_srcdir)/portable \
 	-I$(top_srcdir)/src/common \
 	-I$(top_srcdir)/src/libcommon \
-	-I$(top_srcdir)/src/libmissing \
 	-I$(top_srcdir)/src/libmunge \
 	# End of unmunge_CPPFLAGS
 
 unmunge_LDADD = \
+	$(LIBOBJS) \
 	$(top_builddir)/src/libcommon/libcommon.la \
-	$(top_builddir)/src/libmissing/libmissing.la \
 	$(top_builddir)/src/libmunge/libmunge.la \
 	# End of unmunge_LDADD
 
--- src/munge/unmunge.c.orig
+++ src/munge/unmunge.c
@@ -48,9 +48,9 @@
 #include <unistd.h>
 #include <munge.h>
 #include "common.h"
+#include "inet_ntop.h"
 #include "license.h"
 #include "log.h"
-#include "missing.h"                    /* for inet_ntop()                   */
 #include "read.h"
 #include "version.h"
 #include "xsignal.h"
--- src/munged/Makefile.am.orig
+++ src/munged/Makefile.am
@@ -40,15 +40,15 @@ munged_CPPFLAGS = \
 	-DRUNSTATEDIR='"$(runstatedir)"' \
 	-DSYSCONFDIR='"$(sysconfdir)"' \
 	-DWITH_PTHREADS \
+	-I$(top_srcdir)/portable \
 	-I$(top_srcdir)/src/common \
 	-I$(top_srcdir)/src/libcommon \
-	-I$(top_srcdir)/src/libmissing \
 	-I$(top_srcdir)/src/libmunge \
 	# End of munged_CPPFLAGS
 
 munged_LDADD = \
+	$(LIBOBJS) \
 	$(top_builddir)/src/libcommon/libcommon.la \
-	$(top_builddir)/src/libmissing/libmissing.la \
 	$(top_builddir)/src/libmunge/libmunge.la \
 	$(LIBPTHREAD) \
 	$(LIBBZ2) \
--- src/munged/conf.c.orig
+++ src/munged/conf.c
@@ -29,7 +29,6 @@
 #  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
-#include <arpa/inet.h>                  /* for inet_ntop() */
 #include <assert.h>
 #include <errno.h>
 #include <fcntl.h>
@@ -45,11 +44,11 @@
 #include <munge.h>
 #include "clock.h"
 #include "conf.h"
+#include "inet_ntop.h"
 #include "license.h"
 #include "lock.h"
 #include "log.h"
 #include "md.h"
-#include "missing.h"                    /* for inet_ntop() */
 #include "munge_defs.h"
 #include "net.h"
 #include "path.h"
--- src/munged/munged.c.orig
+++ src/munged/munged.c
@@ -58,12 +58,12 @@
 #include "lock.h"
 #include "log.h"
 #include "md.h"
-#include "missing.h"
 #include "munge_defs.h"
 #include "path.h"
 #include "random.h"
 #include "replay.h"
 #include "str.h"
+#include "strlcpy.h"
 #include "timer.h"
 #include "xsignal.h"
 
--- src/mungekey/Makefile.am.orig
+++ src/mungekey/Makefile.am
@@ -39,13 +39,11 @@ mungekey_CPPFLAGS = \
 	-DSYSCONFDIR='"$(sysconfdir)"' \
 	-I$(top_srcdir)/src/common \
 	-I$(top_srcdir)/src/libcommon \
-	-I$(top_srcdir)/src/libmissing \
 	-I$(top_srcdir)/src/libmunge \
 	# End of mungekey_CPPFLAGS
 
 mungekey_LDADD = \
 	$(top_builddir)/src/libcommon/libcommon.la \
-	$(top_builddir)/src/libmissing/libmissing.la \
 	$(top_builddir)/src/libmunge/libmunge.la \
 	$(CRYPTO_LIBS) \
 	# End of mungekey_LDADD
--- src/mungekey/conf.c.orig
+++ src/mungekey/conf.c
@@ -40,7 +40,6 @@
 #include "conf.h"
 #include "license.h"
 #include "log.h"
-#include "missing.h"
 #include "munge_defs.h"
 #include "version.h"