Andrei G has uploaded this change for review. ( https://gerrit.osmocom.org/c/osmo-ggsn/+/43584?usp=email )
Change subject: configure: search libresolv for res_9_init ......................................................................
configure: search libresolv for res_9_init
sgsnemu points the resolver at the DNS server received in the PCO by writing to the resolver state from <resolv.h>. glibc keeps that state in libc, so nothing extra is needed on GNU/Linux.
Darwin keeps it in libresolv and renames the interface to the BIND 9 symbols: /usr/include/resolv.h has "#define res_init res_9_init" and "#define __res_state __res_9_state". The link of sgsnemu then fails with
Undefined symbols for architecture arm64: "___res_9_state"
Add AC_SEARCH_LIBS([res_9_init], [resolv]) so -lresolv is picked up where the symbol lives there. res_9_init is deliberately the name searched for, rather than res_init: it exists only on the platforms that carry this renaming, so on glibc the search finds nothing, LIBS stays as it was and the link line does not change.
Change-Id: I97787b051c712c5cfdb241cb7931a214d5a87630 Signed-off-by: Andrei Gosman andrei.gosman@gmail.com --- M configure.ac 1 file changed, 4 insertions(+), 0 deletions(-)
git pull ssh://gerrit.osmocom.org:29418/osmo-ggsn refs/changes/84/43584/1
diff --git a/configure.ac b/configure.ac index cbb6b66..3283aae 100644 --- a/configure.ac +++ b/configure.ac @@ -152,6 +152,10 @@ # check for getopt in standard library adl_FUNC_GETOPT_LONG
+# sgsnemu sets the resolver state (_res) from <resolv.h>. glibc keeps it in +# libc; Darwin exports it from libresolv under BIND 9 names (res_9_*). +AC_SEARCH_LIBS([res_9_init], [resolv]) + AM_INIT_AUTOMAKE([foreign])
PKG_CHECK_MODULES(LIBOSMOCORE, libosmocore >= 1.14.2)