Add common handling for libresolv similiar to dlopen(3) wrapping.

For now, DragonFly and FreeBSD use the libc version, it is not reentrant,
but thread-safe. NetBSD 3.0+ and Darwin 8.0+ use libresolv from base
(the BIND9 resolver), all other fall back to net/bind9. Feel free to add
your favorite platform if it has a thread-safe resolver in base.

Modify mail/libspf-alf, mail/milter-greylist, mail/spamdyke and
net/nocol accordingly. Testing on !DragonFly and feedback from tron@

1 files changed, 66 insertions, 0 deletions

diff --git a/mk/resolv.buildlink3.mk b/mk/resolv.buildlink3.mk
new file mode 100644
index 00000000000..30a3f741ac4
--- /dev/null
+++ b/mk/resolv.buildlink3.mk
@@ -0,0 +1,66 @@
+# $NetBSD: resolv.buildlink3.mk,v 1.1 2007/07/03 13:54:45 joerg Exp $
+#
+# This Makefile fragment is included by package Makefiles and
+# buildlink3.mk files for the packages that need a thread-safe
+# DNS resolver..
+#
+# It defines the variables RESOLV_LDFLAGS and RESOLV_LIBS,
+# which are also exported into the CONFIGURE_ENV and MAKE_ENV environments.
+#
+# Package-settable variables:
+#
+# RESOLV_AUTO_VARS
+#	When set to "yes", the necessary flags are added automatically
+#	to LDFLAGS and friends.
+#
+#	Default: no
+#
+# Keywords: resolv
+#
+
+RESOLV_BUILDLINK3_MK:=	${RESOLV_BUILDLINK3_MK}+
+
+.include "../../mk/bsd.fast.prefs.mk"
+
+RESOLV_AUTO_VARS?=	no
+CHECK_BUILTIN.resolv=	no
+
+.if ${OPSYS} == "DragonFly" || ${OPSYS} == "FreeBSD"
+USE_BUILTIN.resolv?=	yes
+
+BUILDLINK_LDFLAGS.resolv=	# empty, in libc
+.elif (${OPSYS} == "NetBSD" && empty(OS_VERSION:M[012].*)) || \
+    (${OPSYS} == "Darwin" && empty(OS_VERSION:M[0123467].*))
+USE_BUILTIN.resolv?=	yes
+
+# BIND 9 resolver
+BUILDLINK_LDFLAGS.resolv=	-lresolv
+.else
+USE_BUILTIN.resolv?=	no
+.endif
+
+.if !empty(USE_BUILTIN.resolv:M[yY][eE][sS])
+BUILDLINK_PACKAGES:=		${BUILDLINK_PACKAGES:Nresolv}
+BUILDLINK_PACKAGES+=		resolv
+BUILDLINK_ORDER:=		${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}resolv
+BUILDLINK_AUTO_VARS.resolv=	${RESOLV_AUTO_VARS}
+.else
+.  include "../../net/bind9/buildlink3.mk"
+
+BUILDLINK_AUTO_VARS.bind=	${RESOLV_AUTO_VARS}
+BUILDLINK_LDFLAGS.resolv=	${BUILDLINK_LDFLAGS.bind}
+BUILDLINK_LIBS.resolv=		${BUILDLINK_LIBS.bind}
+.endif
+
+.if !empty(RESOLV_BUILDLINK3_MK:M+)
+#
+# Define user-visible RESOLV_{LDFLAGS,LIBS} as compiler options used
+# to link code that needs a thread-safe DNS resolver.
+#
+RESOLV_LDFLAGS=	${BUILDLINK_LDFLAGS.resolv}
+RESOLV_LIBS=	${BUILDLINK_LIBS.resolv}
+CONFIGURE_ENV+=	RESOLV_LDFLAGS=${RESOLV_LDFLAGS:Q}
+CONFIGURE_ENV+=	RESOLV_LIBS=${RESOLV_LIBS:Q}
+MAKE_ENV+=	RESOLV_LDFLAGS=${RESOLV_LDFLAGS:Q}
+MAKE_ENV+=	RESOLV_LIBS=${RESOLV_LIBS:Q}
+.endif	# RESOLV_BUILDLINK3_MK