From 72ccc6bb244be27bdbd83a2a4e440d0d9adbef90 Mon Sep 17 00:00:00 2001
From: "Kyle J. McKay" <mackyle@gmail.com>
Date: Tue, 17 Nov 2020 03:22:37 -0700
Subject: [PATCH] make-config-h.sh: add IPV6 config tests

Check for AF_INET6 and IN6ADDR_ANY_INIT to enable IPV6.
Check for inet_ntop to enable INET_NTOP.

Signed-off-by: Kyle J. McKay <mackyle@gmail.com>
---
 src/make-config-h.sh | 112 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 112 insertions(+)

diff --git a/src/make-config-h.sh b/src/make-config-h.sh
index 78fe96a..2bc33c2 100755
--- a/src/make-config-h.sh
+++ b/src/make-config-h.sh
@@ -1,4 +1,116 @@
 #!/bin/sh
 set -e
+die() { >&2 printf '%s: fatal: %s\n' "${0##*/}" "$*"; exit 1; }
+warn() { >&2 printf '%s: %s\n' "${0##*/}" "$*"; }
+
 CC="$1"
 : "${CC:=cc}"
+
+[ "${V#*[!0-9]}" = "$V" ] || V=1
+V="$(( 0 + ${V:-0} ))"
+NOERR='2>&1'
+[ $V -le 1 ] || NOERR=
+
+TMPD=
+cleanup() {
+	[ $V -le 1 ] || [ -z "$TMPD" ] || warn "retaining temp dir $TMPD"
+	[ $V -ge 2 ] || [ -z "$TMPD" ] || rm -rf "$TMPD"
+}
+trap cleanup EXIT
+trap 'exit 129' HUP
+trap 'exit 130' INT
+trap 'exit 131' QUIT
+trap 'exit 134' ABRT
+trap 'exit 141' PIPE
+trap 'exit 142' ALRM
+trap 'exit 143' TERM
+
+# safe printf-based version of echo
+echol() { printf '%s\n' "$*"; }
+
+# set variable with name $1 to name of new writable temp file with .$2 extension
+# if $2 omitted default is "c"
+v_get_temp_ext() {
+	if [ -z "$TMPD" ]; then
+		TMPD="$(mktemp -d /tmp/make-config-h.XXXXXX)" && [ -n "$TMPD" ] && [ -w "$TMPD" ] ||
+			die "could not make temp file directory"
+	fi
+	_tmpf="$(mktemp "$TMPD/source-XXXXXX")" && [ -n "$_tmpf" ] && [ -w "$_tmpf" ] ||
+		die "could not make temp file"
+	mv "$_tmpf" "$_tmpf.${2:-c}" || die "could not rename temp file to have .${2:-c} extension"
+	eval "$1"'="$_tmpf.${2:-c}"'
+}
+
+# attempt to compile "C" source file
+# on standard input with status as only result
+# $1 contains eval'd extra compile args
+testcomp() {
+	v_get_temp_ext _src
+	v_get_temp_ext _obj o
+	cat >"$_src"
+	eval '"$CC" -c -o "$_obj" $1 "$_src" >/dev/null '"$NOERR"
+}
+
+# attempt to compile and link "C" source file
+# on standard input with status as only result
+# $1 contains eval'd extra compile args
+# $2 contains eval'd extra link args
+testlink() {
+	v_get_temp_ext _src
+	v_get_temp_ext _obj o
+	v_get_temp_ext _bin bin
+	cat >"$_src"
+	eval '"$CC" -c -o "$_obj" $1 "$_src" >/dev/null '"$NOERR" &&
+	eval '"$CC" -o "$_bin" $2 "$_obj" >/dev/null '"$NOERR"
+}
+
+# $1 is base name of macro to use (i.e. HAVE_$1)
+# $2 is routine to call (either testcomp or testlink)
+# $3... are optional options to $2
+# standard input is source to compile or compile+link
+emitresult() {
+	_macro="$1"
+	shift
+	[ $V -eq 0 ] || warn "checking for $_macro..."
+	if "$@"; then
+		[ $V -eq 0 ] || warn "  ...HAVE_$_macro => yes"
+		echol "#define HAVE_$_macro 1"
+	else
+		[ $V -eq 0 ] || warn "  ...HAVE_$_macro => no"
+		echol "#undef HAVE_$_macro"
+	fi
+}
+
+# Check for IPV6 (see RFC 3493)
+emitresult IPV6 testcomp <<-IPV6
+	#include <sys/types.h>
+	#include <sys/socket.h>
+	#include <netinet/in.h>
+	#if defined(IN6ADDR_ANY_INIT) && defined(AF_INET6)
+	extern void itworks(void);
+	#else
+	#error missing IPV6
+	#endif
+IPV6
+
+# Check for inet_ntop (see RFC 3493)
+# this is separate in case IPV6 is present but inet_ntop is not
+emitresult INET_NTOP testlink <<-INET_NTOP
+	#include <sys/types.h>
+	#include <sys/socket.h>
+	#include <netinet/in.h>
+	#include <arpa/inet.h>
+	#include <stdio.h>
+	static void check(void)
+	{
+		const char *s;
+		struct in6_addr addr;
+		char str[256];
+		s = inet_ntop(AF_INET6, &addr, str, (socklen_t)sizeof(str));
+		if (s) puts(s);
+	}
+	int main() {
+		check();
+		return 0;
+	}
+INET_NTOP
-- 
2.11.4.GIT