all: avoid coverity warnings about assigning variable but not using it

Workaround coverity warnings like:

  Error: CLANG_WARNING:
  libnl-3.6.0/lib/netfilter/exp.c:428:7: warning[deadcode.DeadStores]: Although the value stored to 'err' is used in the enclosing expression, the value is never actually read from 'err'
  #  426|   	}
  #  427|···
  #  428|-> 	if ((err = nfnl_exp_build_tuple(msg, exp, CTA_EXPECT_NAT)) < 0)
  #  429|   		goto nla_put_failure;
  #  430|···

18 files changed, 29 insertions, 50 deletions

diff --git a/lib/netfilter/exp.c b/lib/netfilter/exp.c
index d1c6c8e..05a6cdc 100644
--- a/lib/netfilter/exp.c
+++ b/lib/netfilter/exp.c
@@ -416,7 +416,6 @@ nla_put_failure:
 static int nfnl_exp_build_nat(struct nl_msg *msg, const struct nfnl_exp *exp)
 {
 	struct nlattr *nat;
-	int err;
 
 	nat = nla_nest_start(msg, CTA_EXPECT_NAT);
 
@@ -425,7 +424,7 @@ static int nfnl_exp_build_nat(struct nl_msg *msg, const struct nfnl_exp *exp)
 				nfnl_exp_get_nat_dir(exp));
 	}
 
-	if ((err = nfnl_exp_build_tuple(msg, exp, CTA_EXPECT_NAT)) < 0)
+	if (nfnl_exp_build_tuple(msg, exp, CTA_EXPECT_NAT) < 0)
 		goto nla_put_failure;
 
 	nla_nest_end(msg, nat);
diff --git a/lib/route/classid.c b/lib/route/classid.c
index 3adb019..350962a 100644
--- a/lib/route/classid.c
+++ b/lib/route/classid.c
@@ -408,7 +408,7 @@ int rtnl_classid_generate(const char *name, uint32_t *result, uint32_t parent)
 
 	fclose(fd);
 
-	if ((err = classid_map_add(classid, name)) < 0) {
+	if (classid_map_add(classid, name) < 0) {
 		/*
 		 * Error adding classid map, re-read classid file is best
 		 * option here. It is likely to fail as well but better
diff --git a/lib/route/cls/ematch.c b/lib/route/cls/ematch.c
index d79f807..9052030 100644
--- a/lib/route/cls/ematch.c
+++ b/lib/route/cls/ematch.c
@@ -693,14 +693,14 @@ int rtnl_ematch_parse_expr(const char *expr, char **errp,
 	if (!(tree = rtnl_ematch_tree_alloc(RTNL_EMATCH_PROGID)))
 		return -NLE_FAILURE;
 
-	if ((err = ematch_lex_init(&scanner)) < 0) {
+	if (ematch_lex_init(&scanner) < 0) {
 		err = -NLE_FAILURE;
 		goto errout;
 	}
 
 	buf = ematch__scan_string(expr, scanner);
 
-	if ((err = ematch_parse(scanner, errp, &tree->et_list)) != 0) {
+	if (ematch_parse(scanner, errp, &tree->et_list) != 0) {
 		ematch__delete_buffer(buf, scanner);
 		err = -NLE_PARSE_ERR;
 		goto errout;
diff --git a/lib/route/link.c b/lib/route/link.c
index 3202600..79c5c5c 100644
--- a/lib/route/link.c
+++ b/lib/route/link.c
@@ -86,13 +86,12 @@ static struct rtnl_link_af_ops *af_lookup_and_alloc(struct rtnl_link *link,
 						    int family)
 {
 	struct rtnl_link_af_ops *af_ops;
-	void *data;
 
 	af_ops = rtnl_link_af_ops_lookup(family);
 	if (!af_ops)
 		return NULL;
 
-	if (!(data = rtnl_link_af_alloc(link, af_ops))) {
+	if (!rtnl_link_af_alloc(link, af_ops)) {
 		rtnl_link_af_ops_put(af_ops);
 		return NULL;
 	}
@@ -3107,22 +3106,16 @@ int rtnl_link_has_vf_list(struct rtnl_link *link) {
 		return 0;
 }
 
-void rtnl_link_set_vf_list(struct rtnl_link *link) {
-	int err;
-
-	if (!(err = rtnl_link_has_vf_list(link)))
+void rtnl_link_set_vf_list(struct rtnl_link *link)
+{
+	if (!rtnl_link_has_vf_list(link))
 		link->ce_mask |= LINK_ATTR_VF_LIST;
-
-	return;
 }
 
-void rtnl_link_unset_vf_list(struct rtnl_link *link) {
-	int err;
-
-	if ((err = rtnl_link_has_vf_list(link)))
+void rtnl_link_unset_vf_list(struct rtnl_link *link)
+{
+	if (rtnl_link_has_vf_list(link))
 		link->ce_mask &= ~LINK_ATTR_VF_LIST;
-
-	return;
 }
 
 /** @} */
diff --git a/lib/route/link/bonding.c b/lib/route/link/bonding.c
index 1d8f89b..90e6470 100644
--- a/lib/route/link/bonding.c
+++ b/lib/route/link/bonding.c
@@ -27,12 +27,11 @@
 struct rtnl_link *rtnl_link_bond_alloc(void)
 {
 	struct rtnl_link *link;
-	int err;
 
 	if (!(link = rtnl_link_alloc()))
 		return NULL;
 
-	if ((err = rtnl_link_set_type(link, "bond")) < 0) {
+	if (rtnl_link_set_type(link, "bond") < 0) {
 		rtnl_link_put(link);
 		return NULL;
 	}
diff --git a/lib/route/link/bridge.c b/lib/route/link/bridge.c
index 639128d..bd04253 100644
--- a/lib/route/link/bridge.c
+++ b/lib/route/link/bridge.c
@@ -458,12 +458,11 @@ static int bridge_compare(struct rtnl_link *_a, struct rtnl_link *_b,
 struct rtnl_link *rtnl_link_bridge_alloc(void)
 {
 	struct rtnl_link *link;
-	int err;
 
 	if (!(link = rtnl_link_alloc()))
 		return NULL;
 
-	if ((err = rtnl_link_set_type(link, "bridge")) < 0) {
+	if (rtnl_link_set_type(link, "bridge") < 0) {
 		rtnl_link_put(link);
 		return NULL;
 	}
diff --git a/lib/route/link/geneve.c b/lib/route/link/geneve.c
index 513a0cf..e52770c 100644
--- a/lib/route/link/geneve.c
+++ b/lib/route/link/geneve.c
@@ -352,12 +352,11 @@ static struct rtnl_link_info_ops geneve_info_ops = {
 struct rtnl_link *rtnl_link_geneve_alloc(void)
 {
         struct rtnl_link *link;
-        int err;
 
         if (!(link = rtnl_link_alloc()))
                 return NULL;
 
-        if ((err = rtnl_link_set_type(link, "geneve")) < 0) {
+        if (rtnl_link_set_type(link, "geneve") < 0) {
                 rtnl_link_put(link);
                 return NULL;
         }
diff --git a/lib/route/link/ipvlan.c b/lib/route/link/ipvlan.c
index 5acf8e2..020f2cb 100644
--- a/lib/route/link/ipvlan.c
+++ b/lib/route/link/ipvlan.c
@@ -172,12 +172,11 @@ static struct rtnl_link_info_ops ipvlan_info_ops = {
 struct rtnl_link *rtnl_link_ipvlan_alloc(void)
 {
 	struct rtnl_link *link;
-	int err;
 
 	if (!(link = rtnl_link_alloc()))
 		return NULL;
 
-	if ((err = rtnl_link_set_type(link, "ipvlan")) < 0) {
+	if (rtnl_link_set_type(link, "ipvlan") < 0) {
 		rtnl_link_put(link);
 		return NULL;
 	}
diff --git a/lib/route/link/macvlan.c b/lib/route/link/macvlan.c
index 48fed6f..df61bb2 100644
--- a/lib/route/link/macvlan.c
+++ b/lib/route/link/macvlan.c
@@ -307,12 +307,11 @@ static struct rtnl_link_info_ops macvtap_info_ops = {
 struct rtnl_link *rtnl_link_macvlan_alloc(void)
 {
 	struct rtnl_link *link;
-	int err;
 
 	if (!(link = rtnl_link_alloc()))
 		return NULL;
 
-	if ((err = rtnl_link_set_type(link, "macvlan")) < 0) {
+	if (rtnl_link_set_type(link, "macvlan") < 0) {
 		rtnl_link_put(link);
 		return NULL;
 	}
@@ -653,12 +652,11 @@ int rtnl_link_macvlan_del_macaddr(struct rtnl_link *link, struct nl_addr *addr)
 struct rtnl_link *rtnl_link_macvtap_alloc(void)
 {
 	struct rtnl_link *link;
-	int err;
 
 	if (!(link = rtnl_link_alloc()))
 		return NULL;
 
-	if ((err = rtnl_link_set_type(link, "macvtap")) < 0) {
+	if (rtnl_link_set_type(link, "macvtap") < 0) {
 		rtnl_link_put(link);
 		return NULL;
 	}
diff --git a/lib/route/link/ppp.c b/lib/route/link/ppp.c
index 73b3245..a5fb400 100644
--- a/lib/route/link/ppp.c
+++ b/lib/route/link/ppp.c
@@ -150,12 +150,11 @@ static struct rtnl_link_info_ops ppp_info_ops = {
 struct rtnl_link *rtnl_link_ppp_alloc(void)
 {
 	struct rtnl_link *link;
-	int err;
 
 	if (!(link = rtnl_link_alloc()))
 		return NULL;
 
-	if ((err = rtnl_link_set_type(link, "ppp")) < 0) {
+	if (rtnl_link_set_type(link, "ppp") < 0) {
 		rtnl_link_put(link);
 		return NULL;
 	}
diff --git a/lib/route/link/sriov.c b/lib/route/link/sriov.c
index 9b3bd32..4008fc9 100644
--- a/lib/route/link/sriov.c
+++ b/lib/route/link/sriov.c
@@ -86,7 +86,7 @@ int rtnl_link_sriov_clone(struct rtnl_link *dst, struct rtnl_link *src) {
 	nl_vf_vlans_t *src_vlans = NULL, *dst_vlans = NULL;
 	nl_vf_vlan_info_t *src_vlan_info = NULL, *dst_vlan_info = NULL;
 
-	if (!(err = rtnl_link_has_vf_list(src)))
+	if (!rtnl_link_has_vf_list(src))
 		return 0;
 
 	dst->l_vf_list = rtnl_link_vf_alloc();
@@ -207,10 +207,9 @@ static void dump_vf_details(struct rtnl_link_vf *vf_data,
 /* Loop through SRIOV VF list dump details */
 void rtnl_link_sriov_dump_details(struct rtnl_link *link,
 				  struct nl_dump_params *p) {
-	int err;
 	struct rtnl_link_vf *vf_data, *list, *next;
 
-	if (!(err = rtnl_link_has_vf_list(link)))
+	if (!rtnl_link_has_vf_list(link))
 		BUG();
 
 	nl_dump(p, "    SRIOV VF List\n");
@@ -271,10 +270,9 @@ void rtnl_link_sriov_dump_stats(struct rtnl_link *link,
 
 /* Free stored SRIOV VF data */
 void rtnl_link_sriov_free_data(struct rtnl_link *link) {
-	int err = 0;
 	struct rtnl_link_vf *list, *vf, *next;
 
-	if (!(err = rtnl_link_has_vf_list(link)))
+	if (!rtnl_link_has_vf_list(link))
 		return;
 
 	list = link->l_vf_list;
diff --git a/lib/route/link/team.c b/lib/route/link/team.c
index 1b47022..1bcc86e 100644
--- a/lib/route/link/team.c
+++ b/lib/route/link/team.c
@@ -27,12 +27,11 @@
 struct rtnl_link *rtnl_link_team_alloc(void)
 {
 	struct rtnl_link *link;
-	int err;
 
 	if (!(link = rtnl_link_alloc()))
 		return NULL;
 
-	if ((err = rtnl_link_set_type(link, "team")) < 0) {
+	if (rtnl_link_set_type(link, "team") < 0) {
 		rtnl_link_put(link);
 		return NULL;
 	}
diff --git a/lib/route/link/veth.c b/lib/route/link/veth.c
index 561693c..37f43f6 100644
--- a/lib/route/link/veth.c
+++ b/lib/route/link/veth.c
@@ -207,11 +207,10 @@ static struct rtnl_link_info_ops veth_info_ops = {
 struct rtnl_link *rtnl_link_veth_alloc(void)
 {
 	struct rtnl_link *link;
-	int err;
 
 	if (!(link = rtnl_link_alloc()))
 		return NULL;
-	if ((err = rtnl_link_set_type(link, "veth")) < 0) {
+	if (rtnl_link_set_type(link, "veth") < 0) {
 		rtnl_link_put(link);
 		return NULL;
 	}
diff --git a/lib/route/link/vlan.c b/lib/route/link/vlan.c
index f7e0ff0..36f8822 100644
--- a/lib/route/link/vlan.c
+++ b/lib/route/link/vlan.c
@@ -386,12 +386,11 @@ static struct rtnl_link_info_ops vlan_info_ops = {
 struct rtnl_link *rtnl_link_vlan_alloc(void)
 {
 	struct rtnl_link *link;
-	int err;
 
 	if (!(link = rtnl_link_alloc()))
 		return NULL;
 
-	if ((err = rtnl_link_set_type(link, "vlan")) < 0) {
+	if (rtnl_link_set_type(link, "vlan") < 0) {
 		rtnl_link_put(link);
 		return NULL;
 	}
diff --git a/lib/route/link/vrf.c b/lib/route/link/vrf.c
index f5c1230..dc8d565 100644
--- a/lib/route/link/vrf.c
+++ b/lib/route/link/vrf.c
@@ -175,12 +175,11 @@ static struct rtnl_link_info_ops vrf_info_ops = {
 struct rtnl_link *rtnl_link_vrf_alloc(void)
 {
 	struct rtnl_link *link;
-	int err;
 
 	if (!(link = rtnl_link_alloc()))
 		return NULL;
 
-	if ((err = rtnl_link_set_type(link, "vrf")) < 0) {
+	if (rtnl_link_set_type(link, "vrf") < 0) {
 		rtnl_link_put(link);
 		return NULL;
 	}
diff --git a/lib/route/link/vxlan.c b/lib/route/link/vxlan.c
index a4a4c44..88cf652 100644
--- a/lib/route/link/vxlan.c
+++ b/lib/route/link/vxlan.c
@@ -695,12 +695,11 @@ static struct rtnl_link_info_ops vxlan_info_ops = {
 struct rtnl_link *rtnl_link_vxlan_alloc(void)
 {
 	struct rtnl_link *link;
-	int err;
 
 	if (!(link = rtnl_link_alloc()))
 		return NULL;
 
-	if ((err = rtnl_link_set_type(link, "vxlan")) < 0) {
+	if (rtnl_link_set_type(link, "vxlan") < 0) {
 		rtnl_link_put(link);
 		return NULL;
 	}
diff --git a/lib/route/pktloc.c b/lib/route/pktloc.c
index 8db427e..599e593 100644
--- a/lib/route/pktloc.c
+++ b/lib/route/pktloc.c
@@ -117,7 +117,7 @@ static int read_pktlocs(void)
 		nl_init_list_head(&pktloc_name_ht[i]);
 	}
 
-	if ((err = pktloc_lex_init(&scanner)) < 0) {
+	if (pktloc_lex_init(&scanner) < 0) {
 		err = -NLE_FAILURE;
 		goto errout_close;
 	}
diff --git a/src/lib/utils.c b/src/lib/utils.c
index 36fb029..2dc7783 100644
--- a/src/lib/utils.c
+++ b/src/lib/utils.c
@@ -229,7 +229,8 @@ void nl_cli_load_module(const char *prefix, const char *name)
 	{
 		void *handle;
 
-		if (!(handle = dlopen(path, RTLD_NOW))) {
+		handle = dlopen(path, RTLD_NOW);
+		if (!handle) {
 			nl_cli_fatal(ENOENT, "Unable to load module \"%s\": %s\n",
 			             path, dlerror());
 		}