[RFC PATCH v2 1/2] platform: move genl_ctrl_resolve to nm-netlink.c

[Javier Arteaga <jarteaga jbeta is>]

Move genl_ctrl_resolve out of the wifi code so it can be reused by other
interfaces based on genetlink.
---
 src/platform/nm-netlink.c              | 68 +++++++++++++++++++++++++++
 src/platform/nm-netlink.h              | 32 +++++++------
 src/platform/wifi/wifi-utils-nl80211.c | 84 ++--------------------------------
 3 files changed, 88 insertions(+), 96 deletions(-)

diff --git a/src/platform/nm-netlink.c b/src/platform/nm-netlink.c
index f93577487..4cb19780b 100644
--- a/src/platform/nm-netlink.c
+++ b/src/platform/nm-netlink.c
@@ -783,6 +783,74 @@ genlmsg_parse (struct nlmsghdr *nlh, int hdrlen, struct nlattr *tb[],
                          genlmsg_attrlen (ghdr, hdrlen), policy);
 }
 
+static int
+_genl_parse_getfamily (struct nl_msg *msg, void *arg)
+{
+       static const struct nla_policy ctrl_policy[CTRL_ATTR_MAX+1] = {
+               [CTRL_ATTR_FAMILY_ID]    = { .type = NLA_U16 },
+               [CTRL_ATTR_FAMILY_NAME]  = { .type = NLA_STRING,
+                                           .maxlen = GENL_NAMSIZ },
+               [CTRL_ATTR_VERSION]      = { .type = NLA_U32 },
+               [CTRL_ATTR_HDRSIZE]      = { .type = NLA_U32 },
+               [CTRL_ATTR_MAXATTR]      = { .type = NLA_U32 },
+               [CTRL_ATTR_OPS]          = { .type = NLA_NESTED },
+               [CTRL_ATTR_MCAST_GROUPS] = { .type = NLA_NESTED },
+       };
+       struct nlattr *tb[CTRL_ATTR_MAX+1];
+       struct nlmsghdr *nlh = nlmsg_hdr (msg);
+       gint32 *response_data = arg;
+
+       if (genlmsg_parse (nlh, 0, tb, CTRL_ATTR_MAX, ctrl_policy))
+               return NL_SKIP;
+
+       if (tb[CTRL_ATTR_FAMILY_ID])
+               *response_data = nla_get_u16 (tb[CTRL_ATTR_FAMILY_ID]);
+
+       return NL_STOP;
+}
+
+int
+genl_ctrl_resolve (struct nl_sock *sk, const char *name)
+{
+       nm_auto_nlmsg struct nl_msg *msg = NULL;
+       int result = -ENOMEM;
+       gint32 response_data = -1;
+       const struct nl_cb cb = {
+               .valid_cb = _genl_parse_getfamily,
+               .valid_arg = &response_data,
+       };
+
+       msg = nlmsg_alloc ();
+
+       if (!genlmsg_put (msg, NL_AUTO_PORT, NL_AUTO_SEQ, GENL_ID_CTRL,
+                         0, 0, CTRL_CMD_GETFAMILY, 1))
+               goto out;
+
+       if (nla_put_string (msg, CTRL_ATTR_FAMILY_NAME, name) < 0)
+               goto out;
+
+       result = nl_send_auto (sk, msg);
+       if (result < 0)
+               goto out;
+
+       result = nl_recvmsgs (sk, &cb);
+       if (result < 0)
+               goto out;
+
+       /* If search was successful, request may be ACKed after data */
+       result = nl_wait_for_ack (sk, NULL);
+       if (result < 0)
+               goto out;
+
+       if (response_data > 0)
+               result = response_data;
+       else
+               result = -ENOENT;
+
+out:
+       return result;
+}
+
 /*****************************************************************************/
 
 struct nl_sock *
diff --git a/src/platform/nm-netlink.h b/src/platform/nm-netlink.h
index 1c89c1880..57b89e1e2 100644
--- a/src/platform/nm-netlink.h
+++ b/src/platform/nm-netlink.h
@@ -409,21 +409,6 @@ struct nlmsghdr *nlmsg_put (struct nl_msg *n, uint32_t pid, uint32_t seq,
 
 /*****************************************************************************/
 
-void *genlmsg_put (struct nl_msg *msg, uint32_t port, uint32_t seq, int family,
-                   int hdrlen, int flags, uint8_t cmd, uint8_t version);
-void *genlmsg_data (const struct genlmsghdr *gnlh);
-void *genlmsg_user_hdr (const struct genlmsghdr *gnlh);
-struct genlmsghdr *genlmsg_hdr (struct nlmsghdr *nlh);
-void *genlmsg_user_data (const struct genlmsghdr *gnlh, const int hdrlen);
-struct nlattr *genlmsg_attrdata (const struct genlmsghdr *gnlh, int hdrlen);
-int genlmsg_len (const struct genlmsghdr *gnlh);
-int genlmsg_attrlen (const struct genlmsghdr *gnlh, int hdrlen);
-int genlmsg_valid_hdr (struct nlmsghdr *nlh, int hdrlen);
-int genlmsg_parse (struct nlmsghdr *nlh, int hdrlen, struct nlattr *tb[],
-                   int maxtype, const struct nla_policy *policy);
-
-/*****************************************************************************/
-
 #define NL_AUTO_PORT 0
 #define NL_AUTO_SEQ  0
 
@@ -506,4 +491,21 @@ int nl_socket_set_ext_ack (struct nl_sock *sk, gboolean enable);
 
 /*****************************************************************************/
 
+void *genlmsg_put (struct nl_msg *msg, uint32_t port, uint32_t seq, int family,
+                   int hdrlen, int flags, uint8_t cmd, uint8_t version);
+void *genlmsg_data (const struct genlmsghdr *gnlh);
+void *genlmsg_user_hdr (const struct genlmsghdr *gnlh);
+struct genlmsghdr *genlmsg_hdr (struct nlmsghdr *nlh);
+void *genlmsg_user_data (const struct genlmsghdr *gnlh, const int hdrlen);
+struct nlattr *genlmsg_attrdata (const struct genlmsghdr *gnlh, int hdrlen);
+int genlmsg_len (const struct genlmsghdr *gnlh);
+int genlmsg_attrlen (const struct genlmsghdr *gnlh, int hdrlen);
+int genlmsg_valid_hdr (struct nlmsghdr *nlh, int hdrlen);
+int genlmsg_parse (struct nlmsghdr *nlh, int hdrlen, struct nlattr *tb[],
+                   int maxtype, const struct nla_policy *policy);
+
+int genl_ctrl_resolve (struct nl_sock *sk, const char *name);
+
+/*****************************************************************************/
+
 #endif /* __NM_NETLINK_H__ */
diff --git a/src/platform/wifi/wifi-utils-nl80211.c b/src/platform/wifi/wifi-utils-nl80211.c
index 769a2be48..db187a1fb 100644
--- a/src/platform/wifi/wifi-utils-nl80211.c
+++ b/src/platform/wifi/wifi-utils-nl80211.c
@@ -46,86 +46,6 @@
                        _NM_UTILS_MACRO_REST(__VA_ARGS__)); \
        } G_STMT_END
 
-/*****************************************************************************
- * Reimplementation of libnl3/genl functions:
- *****************************************************************************/
-
-static int
-probe_response (struct nl_msg *msg, void *arg)
-{
-       static const struct nla_policy ctrl_policy[CTRL_ATTR_MAX+1] = {
-               [CTRL_ATTR_FAMILY_ID]    = { .type = NLA_U16 },
-               [CTRL_ATTR_FAMILY_NAME]  = { .type = NLA_STRING,
-                                           .maxlen = GENL_NAMSIZ },
-               [CTRL_ATTR_VERSION]      = { .type = NLA_U32 },
-               [CTRL_ATTR_HDRSIZE]      = { .type = NLA_U32 },
-               [CTRL_ATTR_MAXATTR]      = { .type = NLA_U32 },
-               [CTRL_ATTR_OPS]          = { .type = NLA_NESTED },
-               [CTRL_ATTR_MCAST_GROUPS] = { .type = NLA_NESTED },
-       };
-       struct nlattr *tb[CTRL_ATTR_MAX+1];
-       struct nlmsghdr *nlh = nlmsg_hdr (msg);
-       gint32 *response_data = arg;
-
-       if (genlmsg_parse (nlh, 0, tb, CTRL_ATTR_MAX, ctrl_policy))
-               return NL_SKIP;
-
-       if (tb[CTRL_ATTR_FAMILY_ID])
-               *response_data = nla_get_u16 (tb[CTRL_ATTR_FAMILY_ID]);
-
-       return NL_STOP;
-}
-
-static int
-genl_ctrl_resolve (struct nl_sock *sk, const char *name)
-{
-       nm_auto_nlmsg struct nl_msg *msg = NULL;
-       int result = -ENOMEM;
-       gint32 response_data = -1;
-       const struct nl_cb cb = {
-               .valid_cb = probe_response,
-               .valid_arg = &response_data,
-       };
-
-       msg = nlmsg_alloc ();
-
-       if (!genlmsg_put (msg, NL_AUTO_PORT, NL_AUTO_SEQ, GENL_ID_CTRL,
-                         0, 0, CTRL_CMD_GETFAMILY, 1))
-               goto out;
-
-       if (nla_put_string (msg, CTRL_ATTR_FAMILY_NAME, name) < 0)
-               goto out;
-
-       result = nl_send_auto (sk, msg);
-       if (result < 0)
-               goto out;
-
-       result = nl_recvmsgs (sk, &cb);
-       if (result < 0)
-               goto out;
-
-       /* If search was successful, request may be ACKed after data */
-       result = nl_wait_for_ack (sk, NULL);
-       if (result < 0)
-               goto out;
-
-       if (response_data > 0)
-               result = response_data;
-       else
-               result = -ENOENT;
-
-out:
-       if (result >= 0)
-               _LOGD (LOGD_WIFI, "genl_ctrl_resolve: resolved \"%s\" as 0x%x", name, result);
-       else
-               _LOGE (LOGD_WIFI, "genl_ctrl_resolve: failed resolve \"%s\"", name);
-       return result;
-}
-
-/*****************************************************************************
- * </libn-genl-3>
- *****************************************************************************/
-
 typedef struct {
        WifiData parent;
        struct nl_sock *nl_sock;
@@ -960,8 +880,10 @@ wifi_nl80211_init (int ifindex)
                goto error;
 
        nl80211->id = genl_ctrl_resolve (nl80211->nl_sock, "nl80211");
-       if (nl80211->id < 0)
+       if (nl80211->id < 0) {
+               _LOGD (LOGD_WIFI, "genl_ctrl_resolve: failed to resolve \"nl80211\"");
                goto error;
+       }
 
        nl80211->phy = -1;
 
-- 
2.16.2