| /* The concept of a subscriber as seen by the BSC */ |
| |
| /* (C) 2008 by Harald Welte <laforge@gnumonks.org> |
| * (C) 2009 by Holger Hans Peter Freyther <zecke@selfish.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 <unistd.h> |
| #include <stdlib.h> |
| #include <stdio.h> |
| #include <string.h> |
| #include <assert.h> |
| |
| #include <osmocore/talloc.h> |
| #include <openbsc/gsm_subscriber.h> |
| #include <openbsc/paging.h> |
| #include <openbsc/debug.h> |
| |
| LLIST_HEAD(active_subscribers); |
| void *tall_subscr_ctx; |
| void *tall_sub_req_ctx; |
| |
| /* for the gsm_subscriber.c */ |
| struct llist_head *subscr_bsc_active_subscriber(void) |
| { |
| return &active_subscribers; |
| } |
| |
| /* |
| * Struct for pending channel requests. This is managed in the |
| * llist_head requests of each subscriber. The reference counting |
| * should work in such a way that a subscriber with a pending request |
| * remains in memory. |
| */ |
| struct subscr_request { |
| struct llist_head entry; |
| |
| /* back reference */ |
| struct gsm_subscriber *subscr; |
| |
| /* the requested channel type */ |
| int channel_type; |
| |
| /* the callback data */ |
| gsm_cbfn *cbfn; |
| void *param; |
| }; |
| |
| /* |
| * We got the channel assigned and can now hand this channel |
| * over to one of our callbacks. |
| */ |
| static int subscr_paging_cb(unsigned int hooknum, unsigned int event, |
| struct msgb *msg, void *data, void *param) |
| { |
| struct subscr_request *request; |
| struct gsm_subscriber *subscr = (struct gsm_subscriber *)param; |
| |
| /* There is no request anymore... */ |
| if (llist_empty(&subscr->requests)) |
| return -1; |
| |
| /* |
| * FIXME: What to do with paging requests coming during |
| * this callback? We must be sure to not start paging when |
| * we have an active connection to a subscriber and to make |
| * the subscr_put_channel work as required... |
| */ |
| request = (struct subscr_request *)subscr->requests.next; |
| llist_del(&request->entry); |
| subscr->in_callback = 1; |
| request->cbfn(hooknum, event, msg, data, request->param); |
| subscr->in_callback = 0; |
| |
| talloc_free(request); |
| return 0; |
| } |
| |
| static void subscr_send_paging_request(struct gsm_subscriber *subscr) |
| { |
| struct subscr_request *request; |
| int rc; |
| |
| assert(!llist_empty(&subscr->requests)); |
| |
| request = (struct subscr_request *)subscr->requests.next; |
| rc = paging_request(subscr->net, subscr, request->channel_type, |
| subscr_paging_cb, subscr); |
| |
| /* paging failed, quit now */ |
| if (rc <= 0) { |
| subscr_paging_cb(GSM_HOOK_RR_PAGING, GSM_PAGING_EXPIRED, |
| NULL, NULL, request->param); |
| } |
| } |
| |
| struct gsm_subscriber *subscr_alloc(void) |
| { |
| struct gsm_subscriber *s; |
| |
| s = talloc_zero(tall_subscr_ctx, struct gsm_subscriber); |
| if (!s) |
| return NULL; |
| |
| llist_add_tail(&s->entry, &active_subscribers); |
| s->use_count = 1; |
| s->tmsi = GSM_RESERVED_TMSI; |
| |
| INIT_LLIST_HEAD(&s->requests); |
| |
| return s; |
| } |
| |
| static void subscr_free(struct gsm_subscriber *subscr) |
| { |
| llist_del(&subscr->entry); |
| talloc_free(subscr); |
| } |
| |
| struct gsm_subscriber *subscr_get(struct gsm_subscriber *subscr) |
| { |
| subscr->use_count++; |
| DEBUGP(DREF, "subscr %s usage increases usage to: %d\n", |
| subscr->extension, subscr->use_count); |
| return subscr; |
| } |
| |
| struct gsm_subscriber *subscr_put(struct gsm_subscriber *subscr) |
| { |
| subscr->use_count--; |
| DEBUGP(DREF, "subscr %s usage decreased usage to: %d\n", |
| subscr->extension, subscr->use_count); |
| if (subscr->use_count <= 0) |
| subscr_free(subscr); |
| return NULL; |
| } |
| |
| void subscr_get_channel(struct gsm_subscriber *subscr, |
| int type, gsm_cbfn *cbfn, void *param) |
| { |
| struct subscr_request *request; |
| |
| request = talloc(tall_sub_req_ctx, struct subscr_request); |
| if (!request) { |
| if (cbfn) |
| cbfn(GSM_HOOK_RR_PAGING, GSM_PAGING_OOM, |
| NULL, NULL, param); |
| return; |
| } |
| |
| memset(request, 0, sizeof(*request)); |
| request->subscr = subscr; |
| request->channel_type = type; |
| request->cbfn = cbfn; |
| request->param = param; |
| |
| /* |
| * FIXME: We might be able to assign more than one |
| * channel, e.g. voice and SMS submit at the same |
| * time. |
| */ |
| if (!subscr->in_callback && llist_empty(&subscr->requests)) { |
| /* add to the list, send a request */ |
| llist_add_tail(&request->entry, &subscr->requests); |
| subscr_send_paging_request(subscr); |
| } else { |
| /* this will be picked up later, from subscr_put_channel */ |
| llist_add_tail(&request->entry, &subscr->requests); |
| } |
| } |
| |
| void subscr_put_channel(struct gsm_lchan *lchan) |
| { |
| /* |
| * FIXME: Continue with other requests now... by checking |
| * the gsm_subscriber inside the gsm_lchan. Drop the ref count |
| * of the lchan after having asked the next requestee to handle |
| * the channel. |
| */ |
| /* |
| * FIXME: is the lchan is of a different type we could still |
| * issue an immediate assignment for another channel and then |
| * close this one. |
| */ |
| /* |
| * Currently we will drop the last ref of the lchan which |
| * will result in a channel release on RSL and we will start |
| * the paging. This should work most of the time as the MS |
| * will listen to the paging requests before we timeout |
| */ |
| |
| put_lchan(lchan); |
| |
| if (lchan->subscr && !llist_empty(&lchan->subscr->requests)) |
| subscr_send_paging_request(lchan->subscr); |
| } |
| |