diff options
Diffstat (limited to 'openbsc/src/transaction.c')
| -rw-r--r-- | openbsc/src/transaction.c | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/openbsc/src/transaction.c b/openbsc/src/transaction.c new file mode 100644 index 000000000..75a279ddc --- /dev/null +++ b/openbsc/src/transaction.c @@ -0,0 +1,171 @@ +/* GSM 04.07 Transaction handling */ + +/* (C) 2009 by Harald Welte <laforge@gnumonks.org> + * All Rights Reserved + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + * + */ + +#include <openbsc/transaction.h> +#include <openbsc/gsm_data.h> +#include <openbsc/mncc.h> +#include <openbsc/debug.h> +#include <osmocore/talloc.h> +#include <openbsc/gsm_subscriber.h> +#include <openbsc/gsm_04_08.h> +#include <openbsc/mncc.h> +#include <openbsc/paging.h> + +void *tall_trans_ctx; + +void _gsm48_cc_trans_free(struct gsm_trans *trans); + +struct gsm_trans *trans_find_by_id(struct gsm_subscriber *subscr, + u_int8_t proto, u_int8_t trans_id) +{ + struct gsm_trans *trans; + struct gsm_network *net = subscr->net; + + llist_for_each_entry(trans, &net->trans_list, entry) { + if (trans->subscr == subscr && + trans->protocol == proto && + trans->transaction_id == trans_id) + return trans; + } + return NULL; +} + +struct gsm_trans *trans_find_by_callref(struct gsm_network *net, + u_int32_t callref) +{ + struct gsm_trans *trans; + + llist_for_each_entry(trans, &net->trans_list, entry) { + if (trans->callref == callref) + return trans; + } + return NULL; +} + +struct gsm_trans *trans_alloc(struct gsm_subscriber *subscr, + u_int8_t protocol, u_int8_t trans_id, + u_int32_t callref) +{ + struct gsm_trans *trans; + + DEBUGP(DCC, "subscr=%p, subscr->net=%p\n", subscr, subscr->net); + + trans = talloc_zero(tall_trans_ctx, struct gsm_trans); + if (!trans) + return NULL; + + trans->subscr = subscr; + subscr_get(trans->subscr); + + trans->protocol = protocol; + trans->transaction_id = trans_id; + trans->callref = callref; + + llist_add_tail(&trans->entry, &subscr->net->trans_list); + + return trans; +} + +void trans_free(struct gsm_trans *trans) +{ + switch (trans->protocol) { + case GSM48_PDISC_CC: + _gsm48_cc_trans_free(trans); + break; + case GSM48_PDISC_SMS: + _gsm411_sms_trans_free(trans); + break; + } + + if (trans->lchan) + put_lchan(trans->lchan); + + if (!trans->lchan && trans->subscr && trans->subscr->net) { + /* Stop paging on all bts' */ + paging_request_stop(NULL, trans->subscr, NULL); + } + + if (trans->subscr) + subscr_put(trans->subscr); + + llist_del(&trans->entry); + + talloc_free(trans); +} + +/* allocate an unused transaction ID for the given subscriber + * in the given protocol using the ti_flag specified */ +int trans_assign_trans_id(struct gsm_subscriber *subscr, + u_int8_t protocol, u_int8_t ti_flag) +{ + struct gsm_network *net = subscr->net; + struct gsm_trans *trans; + unsigned int used_tid_bitmask = 0; + int i, j, h; + + if (ti_flag) + ti_flag = 0x8; + + /* generate bitmask of already-used TIDs for this (subscr,proto) */ + llist_for_each_entry(trans, &net->trans_list, entry) { + if (trans->subscr != subscr || + trans->protocol != protocol || + trans->transaction_id == 0xff) + continue; + used_tid_bitmask |= (1 << trans->transaction_id); + } + + /* find a new one, trying to go in a 'circular' pattern */ + for (h = 6; h > 0; h--) + if (used_tid_bitmask & (1 << (h | ti_flag))) + break; + for (i = 0; i < 7; i++) { + j = ((h + i) % 7) | ti_flag; + if ((used_tid_bitmask & (1 << j)) == 0) + return j; + } + + return -1; +} + +/* update all transactions to use a different LCHAN, e.g. + * after handover has succeeded */ +int trans_lchan_change(struct gsm_lchan *lchan_old, + struct gsm_lchan *lchan_new) +{ + struct gsm_network *net = lchan_old->ts->trx->bts->network; + struct gsm_trans *trans; + int num = 0; + + llist_for_each_entry(trans, &net->trans_list, entry) { + if (trans->lchan == lchan_old) { + /* drop old channel use cound */ + put_lchan(trans->lchan); + /* assign new channel */ + trans->lchan = lchan_new; + /* bump new channel use count */ + use_lchan(trans->lchan); + num++; + } + } + + return num; +} |