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#pragma once
#include <stdint.h>
#include <osmocom/core/linuxlist.h>
#include <osmocom/core/timer.h>
#include <osmocom/gsm/gsm_utils.h>
#include <osmocom/gsm/gsm0808.h>
#include <osmocom/bsc/neighbor_ident.h>
#include <osmocom/bsc/gsm_data.h>
#define LOG_HO(conn, level, fmt, args...) do { \
if (conn->ho.fi) \
LOGPFSML(conn->ho.fi, level, "%s: " fmt, \
handover_status(conn), ## args); \
else \
LOGP(DHODEC, level, "%s: " fmt, \
handover_status(conn), ## args); \
} while(0)
struct gsm_network;
struct gsm_lchan;
struct gsm_bts;
struct gsm_subscriber_connection;
struct gsm_meas_rep mr;
enum handover_result {
HO_RESULT_OK,
HO_RESULT_FAIL_NO_CHANNEL,
HO_RESULT_FAIL_RR_HO_FAIL,
HO_RESULT_FAIL_TIMEOUT,
HO_RESULT_CONN_RELEASE,
HO_RESULT_ERROR,
};
const char *handover_status(struct gsm_subscriber_connection *conn);
extern const struct value_string handover_result_names[];
inline static const char *handover_result_name(enum handover_result val)
{ return get_value_string(handover_result_names, val); }
int bts_handover_count(struct gsm_bts *bts, int ho_scopes);
/* Handover decision algorithms' actions to take on incoming handover-relevant events.
*
* All events that are interesting for handover decision are actually communicated by S_LCHAN_* signals,
* so theoretically, each handover algorithm could evaluate those. However, handover_logic.c cleans up
* handover operation state upon receiving some of these signals. To allow a handover decision algorithm
* to take advantage of e.g. the struct handover before it is discarded, the handover decision event
* handler needs to be invoked before handover_logic.c discards the state. For example, if the handover
* decision wants to place a penalty timer upon a handover failure, it still needs to know which target
* cell the handover failed for; handover_logic.c erases that knowledge on handover failure, since it
* needs to clean up the lchan's handover state.
*
* The most explicit and safest way to ensure the correct order of event handling is to invoke the
* handover decision algorithm's actions from handover_logic.c itself, before cleaning up. This struct
* provides the callback functions for this purpose.
*
* For consistency, also handle signals in this way that aren't actually in danger of interference from
* handover_logic.c (which also saves repeated lookup of handover state for lchans). Thus, handover
* decision algorithms should not register any signal handler at all.
*/
struct handover_decision_callbacks {
struct llist_head entry;
int hodec_id;
void (*on_measurement_report)(struct gsm_meas_rep *mr);
void (*on_handover_end)(struct gsm_subscriber_connection *conn, enum handover_result result);
};
void handover_decision_callbacks_register(struct handover_decision_callbacks *hdc);
struct handover_decision_callbacks *handover_decision_callbacks_get(int hodec_id);
int bsc_tx_bssmap_ho_required(struct gsm_lchan *lchan, const struct gsm0808_cell_id_list2 *target_cells);
int bsc_tx_bssmap_ho_request_ack(struct gsm_subscriber_connection *conn,
struct msgb *rr_ho_command);
int bsc_tx_bssmap_ho_detect(struct gsm_subscriber_connection *conn);
enum handover_result bsc_tx_bssmap_ho_complete(struct gsm_subscriber_connection *conn,
struct gsm_lchan *lchan);
void bsc_tx_bssmap_ho_failure(struct gsm_subscriber_connection *conn);
int find_handover_target_cell(struct gsm_bts **local_target_cell_p,
const struct gsm0808_cell_id_list2 **remote_target_cell_p,
struct gsm_subscriber_connection *conn, const struct neighbor_ident_key *search_for,
bool log_errors);
struct neighbor_ident_key *bts_ident_key(const struct gsm_bts *bts);
void handover_parse_inter_bsc_mt(struct gsm_subscriber_connection *conn,
struct msgb *ho_request_msg);
void handover_mt_allocate_lchan(struct handover *ho);
int handover_mt_send_rr_ho_command(struct handover *ho);
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