From: Harlan Stenn <stenn@ntp.org>
Date: Wed, 14 Oct 2020 05:52:43 +0000 (+0000)
Subject: Implement NTP_FUNC_REALPATH
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7b21aba728587e76855bef1d2359cb037849232d;p=thirdparty%2Fntp.git

Implement NTP_FUNC_REALPATH

bk: 5f86922bzyQmBj2XWvmDxZUqNjIgJA
---

diff --git a/ChangeLog b/ChangeLog
index eeceaa9f1..2e56da12b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+---
+
+* Implement NTP_FUNC_REALPATH.  <stenn@ntp.org>
+
 ---
 (4.2.8p15) 2020/06/23 Released by Harlan Stenn <stenn@ntp.org>
 
diff --git a/configure.ac b/configure.ac
index 5dc6aee02..4e1c1dc67 100644
--- a/configure.ac
+++ b/configure.ac
@@ -900,6 +900,7 @@ case "$host" in
     ;;
 esac
 AC_CHECK_FUNCS([nice plock pututline pututxline readlink rtprio])
+NTP_FUNC_REALPATH
 case "$host" in
  *-*-aix[[4-9]]*)
     # XXX only verified thru AIX6.
diff --git a/sntp/m4/realpath.m4 b/sntp/m4/realpath.m4
new file mode 100644
index 000000000..ad75adc9d
--- /dev/null
+++ b/sntp/m4/realpath.m4
@@ -0,0 +1,50 @@
+#
+# SYNOPSIS
+#
+#   NTP_FUNC_REALPATH
+#
+# DESCRIPTION
+#
+#   This macro defines HAVE_FUNC_REALPATH if we have a realpath()
+#   function that accepts NULL as the 2nd argument.
+#
+# LICENSE
+#
+#   Copyright (c) 2020 Network Time Foundation
+#
+#   Author: Harlan Stenn <stenn@nwtime.org>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved. This file is offered as-is, without any
+#   warranty.
+
+#serial 1
+
+AC_DEFUN([NTP_FUNC_REALPATH], [
+	AC_MSG_CHECKING([whether we have a realpath() that accepts NULL as the 2nd argument])
+	AC_REQUIRE([AC_PROG_CC_C99])
+
+	AC_LANG_PUSH([C])
+
+	AC_RUN_IFELSE(
+		[AC_LANG_SOURCE([[
+			#include <sys/param.h>
+			#include <stdlib.h>
+			int main() { exit (NULL == realpath(".", NULL)); }
+			]])],
+		and="yes",
+		ans="no",
+		ans="CROSS COMPILE!"
+		)
+	AC_MSG_NOTICE([boink])
+	case "$ans" in
+	 yes)
+	    AC_DEFINE([HAVE_FUNC_REALPATH], [1],
+			[Define to 1 if we have realpath() that supports NULL as the 2nd argument]),
+	    ;;
+	esac
+	AC_MSG_RESULT([$ans])
+
+	AC_LANG_POP([C])
+	]);