By mimicking mnl_nft_event_listener() code, mnl_batch_talk() may be
simplified quite a bit:
* Turn the conditional loop into an unconditional one.
* Call select() at loop start, which merges the two call sites.
* Check readfds content after select() returned instead of in loop
condition - if fd is not set, break to return error state stored in
'err' variable.
* Old code checked that select() return code is > 0, but that was
redundant: if FD_ISSET() returns true, select return code was 1.
* Move 'nlh' helper variable definition into error handling block, it is
not used outside of it.
Signed-off-by: Phil Sutter <phil@xxxxxx>
---
src/mnl.c | 26 +++++++++++---------------
1 file changed, 11 insertions(+), 15 deletions(-)
diff --git a/src/mnl.c b/src/mnl.c
index 492d7517d40e2..724decad2e44d 100644
--- a/src/mnl.c
+++ b/src/mnl.c
@@ -278,16 +278,17 @@ int mnl_batch_talk(struct netlink_ctx *ctx, struct list_head *err_list)
if (ret == -1)
return -1;
- FD_ZERO(&readfds);
- FD_SET(fd, &readfds);
-
/* receive and digest all the acknowledgments from the kernel. */
- ret = select(fd+1, &readfds, NULL, NULL, &tv);
- if (ret == -1)
- return -1;
+ while (true) {
+ FD_ZERO(&readfds);
+ FD_SET(fd, &readfds);
+
+ ret = select(fd+1, &readfds, NULL, NULL, &tv);
+ if (ret == -1)
+ return -1;
- while (ret > 0 && FD_ISSET(fd, &readfds)) {
- struct nlmsghdr *nlh = (struct nlmsghdr *)rcv_buf;
+ if (!FD_ISSET(fd, &readfds))
+ break;
ret = mnl_socket_recvfrom(nl, rcv_buf, sizeof(rcv_buf));
if (ret == -1)
@@ -296,16 +297,11 @@ int mnl_batch_talk(struct netlink_ctx *ctx, struct list_head *err_list)
ret = mnl_cb_run(rcv_buf, ret, 0, portid, &netlink_echo_callback, ctx);
/* Continue on error, make sure we get all acknowledgments */
if (ret == -1) {
+ struct nlmsghdr *nlh = (struct nlmsghdr *)rcv_buf;
+
mnl_err_list_node_add(err_list, errno, nlh->nlmsg_seq);
err = -1;
}
-
- FD_ZERO(&readfds);
- FD_SET(fd, &readfds);
-
- ret = select(fd+1, &readfds, NULL, NULL, &tv);
- if (ret == -1)
- return -1;
}
return err;
}
--
2.21.0
