Add s1ap_state get enb/ue funcs

Summary:
As part of our goal to make MME stateless (can crash/update and come back up without losing enb/ue context), we are making the S1AP task stateless as a POC. To make a C program "stateless", we are going off the idea that only the database state needs to be good at all times -- therefore we let the message/state processing happen as normal except that the state is moved from separate globals into one global state that is committed to the db at the end of processing each message.

In this diff, we add getter functions for several parts of S1AP task state (get enb and ue). The purpose of this is to mask implementation detail about how ue's and enb's are stored so that we can change the implementation from OAI hashtable's with manual memory management to C++ maps in the future.

Reviewed By: ssanadhya

Differential Revision: D14685279

fbshipit-source-id: 7b99a936bab0af073bba91cc4c59dbbf626fd7f7

lte/gateway/c/oai/common/security_types.h

@@ -38,10 +38,6 @@
 #include "config.h"
 #endif
 
-#if !defined(HAVE_UINT128_T)
-#include <gmp.h>
-#endif
-
 #ifndef FILE_SECURITY_TYPES_SEEN
 #define FILE_SECURITY_TYPES_SEEN
 

lte/gateway/c/oai/tasks/s1ap/s1ap_state.cpp

@@ -114,6 +114,45 @@ void s1ap_state_put(s1ap_state_t *state)
   in_use = false;
 }
 
+enb_description_t *s1ap_state_get_enb(
+  s1ap_state_t *state,
+  sctp_assoc_id_t assoc_id)
+{
+  enb_description_t *enb = NULL;
+
+  hashtable_ts_get(&state->enbs, (const hash_key_t) assoc_id, (void **) &enb);
+
+  return enb;
+}
+
+ue_description_t *s1ap_state_get_ue_enbid(
+  s1ap_state_t *state,
+  enb_description_t *enb,
+  enb_ue_s1ap_id_t enb_ue_s1ap_id)
+{
+  ue_description_t *ue = NULL;
+
+  hashtable_ts_get(
+    &enb->ue_coll, (const hash_key_t) enb_ue_s1ap_id, (void **) &ue);
+
+  return ue;
+}
+
+ue_description_t *s1ap_state_get_ue_mmeid(
+  s1ap_state_t *state,
+  mme_ue_s1ap_id_t mme_ue_s1ap_id)
+{
+  ue_description_t *ue = NULL;
+
+  hashtable_ts_apply_callback_on_elements(
+    &state->enbs,
+    s1ap_enb_find_ue_by_mme_ue_id_cb,
+    &mme_ue_s1ap_id,
+    (void **) &ue);
+
+  return ue;
+}
+
 s1ap_state_t *s1ap_state_new(void)
 {
   s1ap_state_t *state;

lte/gateway/c/oai/tasks/s1ap/s1ap_state.h

@@ -27,6 +27,8 @@ extern "C" {
 
 #include "hashtable.h"
 
+#include "s1ap_mme.h"
+
 typedef struct s1ap_state_s {
   // contains eNB_description_s, key is eNB_description_s.enb_id (uint32_t)
   hash_table_ts_t enbs;
@@ -40,6 +42,17 @@ void s1ap_state_exit(void);
 s1ap_state_t *s1ap_state_get(void);
 void s1ap_state_put(s1ap_state_t *state);
 
+enb_description_t *s1ap_state_get_enb(
+  s1ap_state_t *state,
+  sctp_assoc_id_t assoc_id);
+ue_description_t *s1ap_state_get_ue_enbid(
+  s1ap_state_t *state,
+  enb_description_t *enb,
+  enb_ue_s1ap_id_t enb_ue_s1ap_id);
+ue_description_t *s1ap_state_get_ue_mmeid(
+  s1ap_state_t *state,
+  mme_ue_s1ap_id_t mme_ue_s1ap_id);
+
 #ifdef __cplusplus
 }
 #endif