On 03/03/2017 10:00 AM, Cédric Bosdonnat wrote:
virNetlinkCommand() processes only one response message, while some
netlink commands like routes dumping need to process several ones.
Add virNetlinkDumpCommand() as a virNetlinkCommand() sister.
---
src/libvirt_private.syms | 1 +
src/util/virnetlink.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++++
src/util/virnetlink.h | 9 ++++++++
3 files changed, 65 insertions(+)
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index bce0487ab..71143851c 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -2117,6 +2117,7 @@ virNetDevVPortProfileOpTypeToString;
# util/virnetlink.h
virNetlinkCommand;
virNetlinkDelLink;
+virNetlinkDumpCommand;
virNetlinkDumpLink;
virNetlinkEventAddClient;
virNetlinkEventRemoveClient;
diff --git a/src/util/virnetlink.c b/src/util/virnetlink.c
index 5fb49251c..4747ba5a4 100644
--- a/src/util/virnetlink.c
+++ b/src/util/virnetlink.c
@@ -335,6 +335,49 @@ int virNetlinkCommand(struct nl_msg *nl_msg,
return ret;
}
+int
+virNetlinkDumpCommand(struct nl_msg *nl_msg,
+ virNetlinkDumpCallback callback,
+ uint32_t src_pid, uint32_t dst_pid,
+ unsigned int protocol, unsigned int groups,
+ void *opaque)
+{
+ int ret = -1;
+ bool end = false;
+ int len = 0;
+ struct nlmsghdr *resp = NULL;
+ struct nlmsghdr *msg = NULL;
+
+ struct sockaddr_nl nladdr = {
+ .nl_family = AF_NETLINK,
+ .nl_pid = dst_pid,
+ .nl_groups = 0,
+ };
+ virNetlinkHandle *nlhandle = NULL;
+
+ if (!(nlhandle = virNetlinkDoCommand(nl_msg, src_pid, nladdr,
+ protocol, groups)))
+ goto cleanup;
+
+ while (!end) {
+ len = nl_recv(nlhandle, &nladdr, (unsigned char **)&resp, NULL);
+
+ for (msg = resp; NLMSG_OK(msg, len); msg = NLMSG_NEXT(msg, len)) {
+ if (msg->nlmsg_type == NLMSG_DONE)
+ end = true;
+
+ if (callback(msg, opaque) < 0)
+ goto cleanup;
This is relying on the callback function to throw an error in order to get us out of the
loop (assuming we never get an NLMSG_DONE). I don't see the callback that's
written in patch 4 doing anything along the lines of virNetlinkGetErrorCode() though.
Maybe you should call that function from here prior to the callback - that would eliminate
the need to separately do that level of error checking in all the future consumers of this
new function.
Otherwise I think it looks okay (I can't claim to have great knowledge of multipart
netlink messages though, so...)