[PATCH iproute2-next 11/15] lib: Extract from iplink_vlan a helper to parse key:value arrays

[Petr Machata]

VLAN netdevices have two similar attributes: ingress-qos-map and
egress-qos-map. These attributes can be configured with a series of
802.1-priority-to-skb-priority (and vice versa) mappings. A reusable helper
along those lines will be handy for configuration of various
priority-to-tc, tc-to-algorithm, and other arrays in DCB. Therefore extract
the logic to a function parse_mapping(), move to utils.c, and dispatch to
utils.c from iplink_vlan.c.

Signed-off-by: Petr Machata <m...@pmachata.org>
---
 include/utils.h  |  4 ++++
 ip/iplink_vlan.c | 37 ++++++++++++++++---------------------
 lib/utils.c      | 28 ++++++++++++++++++++++++++++
 3 files changed, 48 insertions(+), 21 deletions(-)

diff --git a/include/utils.h b/include/utils.h
index 681110fcf8af..8323e3cf1103 100644
--- a/include/utils.h
+++ b/include/utils.h
@@ -339,4 +339,8 @@ int parse_on_off(const char *msg, const char *realval, int 
*p_err);
 void parse_flag_on_off(const char *msg, const char *realval,
                       unsigned int *p_flags, unsigned int flag, int *p_ret);
 
+int parse_mapping(int *argcp, char ***argvp,
+                 int (*mapping_cb)(__u32 key, char *value, void *data),
+                 void *mapping_cb_data);
+
 #endif /* __UTILS_H__ */
diff --git a/ip/iplink_vlan.c b/ip/iplink_vlan.c
index 66c4c0fb57f1..73aa94acde3c 100644
--- a/ip/iplink_vlan.c
+++ b/ip/iplink_vlan.c
@@ -43,36 +43,31 @@ static void explain(void)
        print_explain(stderr);
 }
 
+static int parse_qos_mapping(__u32 key, char *value, void *data)
+{
+       struct nlmsghdr *n = data;
+       struct ifla_vlan_qos_mapping m = {
+               .from = key,
+       };
+
+       if (get_u32(&m.to, value, 0))
+               return 1;
+
+       addattr_l(n, 1024, IFLA_VLAN_QOS_MAPPING, &m, sizeof(m));
+       return 0;
+}
+
 static int vlan_parse_qos_map(int *argcp, char ***argvp, struct nlmsghdr *n,
                              int attrtype)
 {
-       int argc = *argcp;
-       char **argv = *argvp;
-       struct ifla_vlan_qos_mapping m;
        struct rtattr *tail;
 
        tail = addattr_nest(n, 1024, attrtype);
 
-       while (argc > 0) {
-               char *colon = strchr(*argv, ':');
-
-               if (!colon)
-                       break;
-               *colon = '\0';
-
-               if (get_u32(&m.from, *argv, 0))
-                       return 1;
-               if (get_u32(&m.to, colon + 1, 0))
-                       return 1;
-               argc--, argv++;
-
-               addattr_l(n, 1024, IFLA_VLAN_QOS_MAPPING, &m, sizeof(m));
-       }
+       if (parse_mapping(argcp, argvp, &parse_qos_mapping, n))
+               return 1;
 
        addattr_nest_end(n, tail);
-
-       *argcp = argc;
-       *argvp = argv;
        return 0;
 }
 
diff --git a/lib/utils.c b/lib/utils.c
index fb25c64d36ff..93521a49eaec 100644
--- a/lib/utils.c
+++ b/lib/utils.c
@@ -1774,3 +1774,31 @@ void parse_flag_on_off(const char *msg, const char 
*realval,
 
        set_flag(p_flags, flag, on_off);
 }
+
+int parse_mapping(int *argcp, char ***argvp,
+                 int (*mapping_cb)(__u32 key, char *value, void *data),
+                 void *mapping_cb_data)
+{
+       int argc = *argcp;
+       char **argv = *argvp;
+
+       while (argc > 0) {
+               char *colon = strchr(*argv, ':');
+               __u32 key;
+
+               if (!colon)
+                       break;
+               *colon = '\0';
+
+               if (get_u32(&key, *argv, 0))
+                       return 1;
+               if (mapping_cb(key, colon + 1, mapping_cb_data))
+                       return 1;
+
+               argc--, argv++;
+       }
+
+       *argcp = argc;
+       *argvp = argv;
+       return 0;
+}
-- 
2.25.1