SDL_ttf: added a customized tar.m4 under our acinclude directory:

From ce5a8878e79ce4480bedd979f576bbee22d9f6f6 Mon Sep 17 00:00:00 2001
From: Ozkan Sezer <[EMAIL REDACTED]>
Date: Fri, 16 Apr 2021 11:24:04 +0300
Subject: [PATCH] added a customized tar.m4 under our acinclude directory:

No following the symlinks: removed tar 'h' and cpio/pax '-L' switches.
---
 acinclude/tar.m4 | 133 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 133 insertions(+)
 create mode 100644 acinclude/tar.m4

diff --git a/acinclude/tar.m4 b/acinclude/tar.m4
new file mode 100644
index 0000000..1469f54
--- /dev/null
+++ b/acinclude/tar.m4
@@ -0,0 +1,133 @@
+# Check how to create a tarball.                            -*- Autoconf -*-
+
+# Copyright (C) 2004-2020 Free Software Foundation, Inc.
+#
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+# _AM_PROG_TAR(FORMAT)
+# --------------------
+# Check how to create a tarball in format FORMAT.
+# FORMAT should be one of 'v7', 'ustar', or 'pax'.
+#
+# Substitute a variable $(am__tar) that is a command
+# writing to stdout a FORMAT-tarball containing the directory
+# $tardir.
+#     tardir=directory && $(am__tar) > result.tar
+#
+# Substitute a variable $(am__untar) that extract such
+# a tarball read from stdin.
+#     $(am__untar) < result.tar
+#
+AC_DEFUN([_AM_PROG_TAR],
+[# Always define AMTAR for backward compatibility.  Yes, it's still used
+# in the wild :-(  We should find a proper way to deprecate it ...
+AC_SUBST([AMTAR], ['$${TAR-tar}'])
+
+# We'll loop over all known methods to create a tar archive until one works.
+_am_tools='gnutar m4_if([$1], [ustar], [plaintar]) pax cpio none'
+
+dnl SDL: No following the symlinks: removed tar 'h' and cpio/pax '-L' switches
+m4_if([$1], [v7],
+  [am__tar='$${TAR-tar} cof - "$$tardir"' am__untar='$${TAR-tar} xf -'],
+
+  [m4_case([$1],
+    [ustar],
+     [# The POSIX 1988 'ustar' format is defined with fixed-size fields.
+      # There is notably a 21 bits limit for the UID and the GID.  In fact,
+      # the 'pax' utility can hang on bigger UID/GID (see automake bug#8343
+      # and bug#13588).
+      am_max_uid=2097151 # 2^21 - 1
+      am_max_gid=$am_max_uid
+      # The $UID and $GID variables are not portable, so we need to resort
+      # to the POSIX-mandated id(1) utility.  Errors in the 'id' calls
+      # below are definitely unexpected, so allow the users to see them
+      # (that is, avoid stderr redirection).
+      am_uid=`id -u || echo unknown`
+      am_gid=`id -g || echo unknown`
+      AC_MSG_CHECKING([whether UID '$am_uid' is supported by ustar format])
+      if test $am_uid -le $am_max_uid; then
+         AC_MSG_RESULT([yes])
+      else
+         AC_MSG_RESULT([no])
+         _am_tools=none
+      fi
+      AC_MSG_CHECKING([whether GID '$am_gid' is supported by ustar format])
+      if test $am_gid -le $am_max_gid; then
+         AC_MSG_RESULT([yes])
+      else
+        AC_MSG_RESULT([no])
+        _am_tools=none
+      fi],
+
+  [pax],
+    [],
+
+  [m4_fatal([Unknown tar format])])
+
+  AC_MSG_CHECKING([how to create a $1 tar archive])
+
+  # Go ahead even if we have the value already cached.  We do so because we
+  # need to set the values for the 'am__tar' and 'am__untar' variables.
+  _am_tools=${am_cv_prog_tar_$1-$_am_tools}
+
+  for _am_tool in $_am_tools; do
+    case $_am_tool in
+    gnutar)
+      for _am_tar in tar gnutar gtar; do
+        AM_RUN_LOG([$_am_tar --version]) && break
+      done
+      am__tar="$_am_tar --format=m4_if([$1], [pax], [posix], [$1]) -cf - "'"$$tardir"'
+      am__tar_="$_am_tar --format=m4_if([$1], [pax], [posix], [$1]) -cf - "'"$tardir"'
+      am__untar="$_am_tar -xf -"
+      ;;
+    plaintar)
+      # Must skip GNU tar: if it does not support --format= it doesn't create
+      # ustar tarball either.
+      (tar --version) >/dev/null 2>&1 && continue
+      am__tar='tar cf - "$$tardir"'
+      am__tar_='tar cf - "$tardir"'
+      am__untar='tar xf -'
+      ;;
+    pax)
+      am__tar='pax -x $1 -w "$$tardir"'
+      am__tar_='pax -x $1 -w "$tardir"'
+      am__untar='pax -r'
+      ;;
+    cpio)
+      am__tar='find "$$tardir" -print | cpio -o -H $1'
+      am__tar_='find "$tardir" -print | cpio -o -H $1'
+      am__untar='cpio -i -H $1 -d'
+      ;;
+    none)
+      am__tar=false
+      am__tar_=false
+      am__untar=false
+      ;;
+    esac
+
+    # If the value was cached, stop now.  We just wanted to have am__tar
+    # and am__untar set.
+    test -n "${am_cv_prog_tar_$1}" && break
+
+    # tar/untar a dummy directory, and stop if the command works.
+    rm -rf conftest.dir
+    mkdir conftest.dir
+    echo GrepMe > conftest.dir/file
+    AM_RUN_LOG([tardir=conftest.dir && eval $am__tar_ >conftest.tar])
+    rm -rf conftest.dir
+    if test -s conftest.tar; then
+      AM_RUN_LOG([$am__untar <conftest.tar])
+      AM_RUN_LOG([cat conftest.dir/file])
+      grep GrepMe conftest.dir/file >/dev/null 2>&1 && break
+    fi
+  done
+  rm -rf conftest.dir
+
+  AC_CACHE_VAL([am_cv_prog_tar_$1], [am_cv_prog_tar_$1=$_am_tool])
+  AC_MSG_RESULT([$am_cv_prog_tar_$1])])
+
+AC_SUBST([am__tar])
+AC_SUBST([am__untar])
+]) # _AM_PROG_TAR