change GSM48_CMSERV_* to enum type, add names

Prepare handling multiple CM Service Requests in osmo-msc: an enum is more
clear than an int and #defines for passing around and count CM Service types.

Change-Id: I9c2a7adc45ab7a1a7519168e965e7d805e1481ff

include/osmocom/gsm/protocol/gsm_04_08.h

@@ -1631,13 +1631,20 @@ const char *gsm48_pdisc_msgtype_name(uint8_t pdisc, uint8_t msg_type);
 /* FIXME: Table 10.4 / 10.4a (GPRS) */
 
 /* Section 10.5.3.3 CM service type */
-#define GSM48_CMSERV_MO_CALL_PACKET	1
-#define GSM48_CMSERV_EMERGENCY		2
-#define GSM48_CMSERV_SMS		4
-#define GSM48_CMSERV_SUP_SERV		8
-#define GSM48_CMSERV_VGCS		9
-#define GSM48_CMSERV_VBS		10
-#define GSM48_CMSERV_LOC_SERV		11
+enum osmo_cm_service_type {
+	GSM48_CMSERV_MO_CALL_PACKET	= 1,
+	GSM48_CMSERV_EMERGENCY		= 2,
+	GSM48_CMSERV_SMS		= 4,
+	GSM48_CMSERV_SUP_SERV		= 8,
+	GSM48_CMSERV_VGCS		= 9,
+	GSM48_CMSERV_VBS		= 10,
+	GSM48_CMSERV_LOC_SERV		= 11,
+	GSM48_CMSERV_MAX_VAL		= GSM48_CMSERV_LOC_SERV
+};
+
+extern const struct value_string osmo_cm_service_type_names[];
+static inline const char *osmo_cm_service_type_name(enum osmo_cm_service_type val)
+{ return get_value_string(osmo_cm_service_type_names, val); }
 
 /* Section 10.5.2.26, Table 10.5.64 */
 #define GSM48_PM_MASK		0x03

src/gsm/gsm48.c

@@ -1145,4 +1145,15 @@ const struct value_string osmo_lu_type_names[] = {
 	{}
 };
 
+const struct value_string osmo_cm_service_type_names[] = {
+	{ GSM48_CMSERV_MO_CALL_PACKET, "MO-Call" },
+	{ GSM48_CMSERV_EMERGENCY, "Emergency-Call" },
+	{ GSM48_CMSERV_SMS, "Short-Messaging-Service" },
+	{ GSM48_CMSERV_SUP_SERV, "Supplementary-Service" },
+	{ GSM48_CMSERV_VGCS, "Voice-Group-Call" },
+	{ GSM48_CMSERV_VBS, "Voice-Broadcast-Call" },
+	{ GSM48_CMSERV_LOC_SERV, "Location-Service" },
+	{}
+};
+
 /*! @} */

src/gsm/libosmogsm.map

@@ -574,6 +574,7 @@ sgsap_ie_tlvdef;
 
 osmo_rat_type_names;
 osmo_lu_type_names;
+osmo_cm_service_type_names;
 
 local: *;
 };