[PATCH iproute2-next v2 2/6] devlink: Introduce and use string to number mapper

[Parav Pandit <parav@nvidia.com>]

Instead of using static mapping in code, introduce a helper routine to
map a value to string.

Signed-off-by: Parav Pandit <parav@nvidia.com>
---
changelog:
v1->v2:
 - addressed David's comment to use helper routine to map num->string
---
 devlink/devlink.c | 30 ++++++++++++++----------------
 include/utils.h   |  8 ++++++++
 lib/utils.c       | 28 ++++++++++++++++++++++++++++
 3 files changed, 50 insertions(+), 16 deletions(-)

diff --git a/devlink/devlink.c b/devlink/devlink.c
index a2e06644..d21a7c4d 100644
--- a/devlink/devlink.c
+++ b/devlink/devlink.c
@@ -1383,6 +1383,16 @@ static int reload_limit_get(struct dl *dl, const char *limitstr,
 	return 0;
 }
 
+static struct str_num_map port_flavour_map[] = {
+	{ .str = "physical", .num = DEVLINK_PORT_FLAVOUR_PHYSICAL },
+	{ .str = "cpu", .num = DEVLINK_PORT_FLAVOUR_CPU },
+	{ .str = "dsa", .num = DEVLINK_PORT_FLAVOUR_DSA },
+	{ .str = "pcipf", .num = DEVLINK_PORT_FLAVOUR_PCI_PF },
+	{ .str = "pcivf", .num = DEVLINK_PORT_FLAVOUR_PCI_VF },
+	{ .str = "virtual", .num = DEVLINK_PORT_FLAVOUR_VIRTUAL},
+	{ .str = NULL, },
+};
+
 struct dl_args_metadata {
 	uint64_t o_flag;
 	char err_msg[DL_ARGS_REQUIRED_MAX_ERR_LEN];
@@ -3717,22 +3727,10 @@ static const char *port_type_name(uint32_t type)
 
 static const char *port_flavour_name(uint16_t flavour)
 {
-	switch (flavour) {
-	case DEVLINK_PORT_FLAVOUR_PHYSICAL:
-		return "physical";
-	case DEVLINK_PORT_FLAVOUR_CPU:
-		return "cpu";
-	case DEVLINK_PORT_FLAVOUR_DSA:
-		return "dsa";
-	case DEVLINK_PORT_FLAVOUR_PCI_PF:
-		return "pcipf";
-	case DEVLINK_PORT_FLAVOUR_PCI_VF:
-		return "pcivf";
-	case DEVLINK_PORT_FLAVOUR_VIRTUAL:
-		return "virtual";
-	default:
-		return "<unknown flavour>";
-	}
+	const char *str;
+
+	str = str_map_lookup_u16(port_flavour_map, flavour);
+	return str ? str : "<unknown flavour>";
 }
 
 static void pr_out_port_pfvf_num(struct dl *dl, struct nlattr **tb)
diff --git a/include/utils.h b/include/utils.h
index f1403f73..1d67443e 100644
--- a/include/utils.h
+++ b/include/utils.h
@@ -340,4 +340,12 @@ int parse_mapping(int *argcp, char ***argvp, bool allow_all,
 		  int (*mapping_cb)(__u32 key, char *value, void *data),
 		  void *mapping_cb_data);
 
+struct str_num_map {
+	const char *str;
+	int num;
+};
+
+int str_map_lookup_str(const struct str_num_map *map, const char *needle);
+const char *str_map_lookup_u16(const struct str_num_map *map, uint16_t val);
+
 #endif /* __UTILS_H__ */
diff --git a/lib/utils.c b/lib/utils.c
index 90e58fa3..9fef2d76 100644
--- a/lib/utils.c
+++ b/lib/utils.c
@@ -1937,3 +1937,31 @@ int parse_mapping(int *argcp, char ***argvp, bool allow_all,
 		return parse_mapping_gen(argcp, argvp, parse_mapping_num,
 					 mapping_cb, mapping_cb_data);
 }
+
+int str_map_lookup_str(const struct str_num_map *map, const char *needle)
+{
+	if (!needle)
+		return -EINVAL;
+
+	/* Process array which is NULL terminated by the string. */
+	while (map && map->str) {
+		if (strcmp(map->str, needle) == 0)
+			return map->num;
+
+		map++;
+	}
+	return -EINVAL;
+}
+
+const char *str_map_lookup_u16(const struct str_num_map *map, uint16_t val)
+{
+	int num = val;
+
+	while (map && map->str) {
+		if (num == map->num)
+			return map->str;
+
+		map++;
+	}
+	return NULL;
+}
-- 
2.26.2