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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>
struct gsm_lchan;
struct gsm_bts;
struct gsm_subscriber_connection;
struct gsm_meas_rep mr;
#define LOGPHOLCHANTOLCHAN(old_lchan, new_lchan, level, fmt, args...) \
LOGP(DHODEC, level, "(BTS %u trx %u arfcn %u ts %u lchan %u %s %s)->(BTS %u trx %u arfcn %u ts %u lchan %u %s) (subscr %s) " fmt, \
old_lchan->ts->trx->bts->nr, \
old_lchan->ts->trx->nr, \
old_lchan->ts->trx->arfcn, \
old_lchan->ts->nr, \
old_lchan->nr, \
gsm_lchant_name(old_lchan->type), \
gsm48_chan_mode_name(old_lchan->tch_mode), \
new_lchan->ts->trx->bts->nr, \
new_lchan->ts->trx->nr, \
new_lchan->ts->trx->arfcn, \
new_lchan->ts->nr, \
new_lchan->nr, \
gsm_pchan_name(new_lchan->ts->pchan), \
bsc_subscr_name(old_lchan->conn? old_lchan->conn->bsub : NULL), \
## args)
#define LOGPHO(struct_bsc_handover, level, fmt, args ...) \
LOGPHOLCHANTOLCHAN(struct_bsc_handover->old_lchan, struct_bsc_handover->new_lchan, level, fmt, ## args)
enum hodec_id {
HODEC_NONE,
HODEC1 = 1,
HODEC2 = 2,
};
struct bsc_handover {
struct llist_head list;
/* Initial details of what is requested */
struct gsm_lchan *old_lchan;
struct gsm_bts *new_bts;
enum gsm_chan_t new_lchan_type;
bool async;
/* Derived and resulting state */
bool inter_cell;
uint8_t ho_ref;
enum hodec_id from_hodec_id;
struct gsm_lchan *new_lchan;
struct osmo_timer_list T3103;
};
int bsc_handover_start(enum hodec_id from_hodec_id, struct gsm_lchan *old_lchan, struct gsm_bts *new_bts,
enum gsm_chan_t new_lchan_type);
int bsc_handover_start_gscon(struct gsm_subscriber_connection *conn);
void bsc_clear_handover(struct gsm_subscriber_connection *conn, int free_lchan);
struct gsm_lchan *bsc_handover_pending(struct gsm_lchan *new_lchan);
int bsc_ho_count(struct gsm_bts *bts, bool inter_cell);
/* 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 bsc_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_ho_chan_activ_nack)(struct bsc_handover *ho);
void (*on_ho_failure)(struct bsc_handover *ho);
};
void handover_decision_callbacks_register(struct handover_decision_callbacks *hdc);
struct handover_decision_callbacks *handover_decision_callbacks_get(int hodec_id);
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