build: check for fopencookie() in configure

fopencookie(3) is a non-standard GNU extension and some libc
implementations might not provide it (e.g. musl).

Check for fopencookie in the configure script and disable building
curvetun in case the function is not available, as curvetun is the only
tool using fopencookie.

Fixes #174
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>

1 files changed, 42 insertions, 9 deletions

diff --git a/configure b/configure
index e2b62fe..d5fe7e6 100755
--- a/configure
+++ b/configure
@@ -388,6 +388,31 @@ EOF
 	fi
 }
 
+check_fopencookie()
+{
+	echo -n "[*] Checking fopencookie ... "
+
+	cat > $TMPDIR/fopencookietest.c << EOF
+#define _GNU_SOURCE
+#include <stdio.h>
+
+static cookie_io_functions_t cookie_fns;
+
+int main(void)
+{
+	FILE *f = fopencookie(NULL, "w", cookie_fns);
+}
+EOF
+
+	$CC -o $TMPDIR/fopencookietest $TMPDIR/fopencookietest.c >> config.log 2>&1
+	if [ ! -x $TMPDIR/fopencookietest ] ; then
+		echo "[NO]"
+		MISSING_DEFS=1
+		tools_remove "curvetun"
+	else
+		echo "[YES]"
+	fi
+}
 
 check_ncurses()
 {
@@ -766,22 +791,30 @@ if [ "$MISSING_TOOLCHAIN" == "1" ] ; then
 	exit 1
 fi
 
+# external tools
 check_flex
 check_bison
-check_nacl
-check_libnl
-check_libnl_route
+
+# kernel features
 check_tpacket_v2
 check_tpacket_v3
-check_libnf_ct
-check_ncurses
-check_libgeoip
-check_zlib
-check_urcu
-check_libpcap
 check_hwtstamp
+
+# libc features
+check_fopencookie
+
+# libraries
 check_libcli
+check_libgeoip
 check_libnet
+check_libnf_ct
+check_libnl
+check_libnl_route
+check_libpcap
+check_nacl
+check_ncurses
+check_urcu
+check_zlib
 
 gen_config_hdr
 gen_version_appendix