187 lines
6.6 KiB
C
187 lines
6.6 KiB
C
/* (C) 2021 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
|
|
* All Rights Reserved
|
|
*
|
|
* Author: Philipp Maier
|
|
*
|
|
* 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, see <http://www.gnu.org/licenses/>.
|
|
*
|
|
*/
|
|
|
|
#include <osmocom/mgcp_client/mgcp_client.h>
|
|
#include <osmocom/mgcp_client/mgcp_client_internal.h>
|
|
#include <osmocom/mgcp_client/mgcp_client_pool_internal.h>
|
|
#include <osmocom/mgcp_client/mgcp_client_pool.h>
|
|
#include <stddef.h>
|
|
|
|
/*! Allocate MGCP client pool. This is called once on startup and before the pool is used with
|
|
* mgcp_client_pool_vty_init(). Since the pool is linked with the VTY it must exist througout the entire runtime.
|
|
* \param[in] talloc_ctx talloc context. */
|
|
struct mgcp_client_pool *mgcp_client_pool_alloc(void *talloc_ctx)
|
|
{
|
|
struct mgcp_client_pool *pool;
|
|
|
|
pool = talloc_zero(talloc_ctx, struct mgcp_client_pool);
|
|
if (!pool)
|
|
return NULL;
|
|
|
|
INIT_LLIST_HEAD(&pool->pool);
|
|
|
|
return pool;
|
|
}
|
|
|
|
/*! Initialize and connect an mcgp client pool.
|
|
* \param[in,out] mgcp MGCP client pool descriptor.
|
|
* \returns number of successfully initialized pool members. */
|
|
unsigned int mgcp_client_pool_connect(struct mgcp_client_pool *pool)
|
|
{
|
|
struct mgcp_client_pool_member *pool_member;
|
|
unsigned int pool_members_initialized = 0;
|
|
|
|
llist_for_each_entry(pool_member, &pool->pool, list) {
|
|
|
|
/* Initialize client */
|
|
pool_member->client = mgcp_client_init(pool_member, &pool_member->conf);
|
|
if (!pool_member->client) {
|
|
LOGP(DLMGCP, LOGL_ERROR, "MGW %u initialization failed\n", pool_member->nr);
|
|
continue;
|
|
}
|
|
|
|
/* Set backpointer so that we can detect later that this MGCP client is managed
|
|
* by this pool. */
|
|
pool_member->client->pool = pool;
|
|
|
|
/* Connect client */
|
|
if (mgcp_client_connect2(pool_member->client, 0)) {
|
|
LOGP(DLMGCP, LOGL_ERROR, "MGW %u connect failed at (%s:%u)\n",
|
|
pool_member->nr, pool_member->conf.remote_addr, pool_member->conf.remote_port);
|
|
talloc_free(pool_member->client);
|
|
pool_member->client = NULL;
|
|
continue;
|
|
}
|
|
|
|
pool_members_initialized++;
|
|
}
|
|
|
|
return pool_members_initialized;
|
|
}
|
|
|
|
/*! register a single mgcp_client instance to the pool.
|
|
* \param[out] pool MGCP client pool descriptor.
|
|
* \param[in] mgcp MGCP client descriptor. */
|
|
void mgcp_client_pool_register_single(struct mgcp_client_pool *pool, struct mgcp_client *mgcp_client)
|
|
{
|
|
/*! Some applications still support the non-pooled MGW VTY configuration variant provided by
|
|
* mgcp_client_vty_init(). If this is the case the mgcp_client instance created by mgcp_client_init()
|
|
* can be registered here so that it will appear as if it were part of the pool. When the user actively
|
|
* configures MGW pool members, the MGCP client registered here will be ignored. (The registration of
|
|
* multiple singe mgcp_client instances is not possible.) */
|
|
pool->mgcp_client_single = mgcp_client;
|
|
}
|
|
|
|
/* Not every pool member may have a functional MGCP client, we will run through the pool once until we meet a
|
|
* pool member that is suitable (has a client, is not blocked, has a low load). */
|
|
static struct mgcp_client_pool_member *mgcp_client_pool_pick(struct mgcp_client_pool *pool)
|
|
{
|
|
struct mgcp_client_pool_member *pool_member;
|
|
struct mgcp_client_pool_member *pool_member_picked = NULL;
|
|
unsigned int n_pool_members = llist_count(&pool->pool);
|
|
|
|
llist_for_each_entry(pool_member, &pool->pool, list) {
|
|
if (pool_member->blocked == false && pool_member->client) {
|
|
if (!pool_member_picked)
|
|
pool_member_picked = pool_member;
|
|
else if (pool_member_picked->refcount > pool_member->refcount)
|
|
pool_member_picked = pool_member;
|
|
} else {
|
|
LOGP(DLMGCP, LOGL_DEBUG, "MGW pool has %u members -- MGW %u is unusable\n", n_pool_members,
|
|
pool_member->nr);
|
|
}
|
|
}
|
|
|
|
if (pool_member_picked) {
|
|
LOGP(DLMGCP, LOGL_DEBUG, "MGW pool has %u members -- using MGW %u (active calls: %u)\n",
|
|
n_pool_members, pool_member_picked->nr, pool_member_picked->refcount);
|
|
return pool_member_picked;
|
|
}
|
|
|
|
LOGP(DLMGCP, LOGL_ERROR,
|
|
"MGW pool has %u members, but no functional MGW pool member found -- check configuration!\n",
|
|
n_pool_members);
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*! get an MGCP client from the pool (increment reference counter).
|
|
* \param[in,out] pool MGCP client pool descriptor.
|
|
* \returns MGCP client descriptor, NULL if no member was found (empty pool). */
|
|
struct mgcp_client *mgcp_client_pool_get(struct mgcp_client_pool *pool)
|
|
{
|
|
struct mgcp_client_pool_member *pool_member;
|
|
|
|
/*! When an MGCP client is taken from the pool it is still available for other calls. In fact only a reference
|
|
* counter is incremented to keep track on how many references to a specific MGCP client are currently used
|
|
* by the application code. */
|
|
|
|
/* When the pool is empty, return a single MGCP client if it is registered. */
|
|
if (llist_empty(&pool->pool) && pool->mgcp_client_single) {
|
|
LOGP(DLMGCP, LOGL_DEBUG, "MGW pool is empty -- using (single) MGW\n");
|
|
return pool->mgcp_client_single;
|
|
}
|
|
|
|
/* Abort when the pool is empty */
|
|
if (llist_empty(&pool->pool)) {
|
|
LOGP(DLMGCP, LOGL_ERROR, "MGW pool is empty -- no MGW available!\n");
|
|
return NULL;
|
|
}
|
|
|
|
/* Pick a suitable pool member */
|
|
pool_member = mgcp_client_pool_pick(pool);
|
|
if (pool_member) {
|
|
pool_member->refcount++;
|
|
return pool_member->client;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*! put an MGCP client back into the pool (decrement reference counter).
|
|
* \param[in,out] pool MGCP client pool descriptor.
|
|
* \param[in] mgcp MGCP client descriptor.
|
|
*
|
|
* This function is able to detect automatically to which pool the mgcp_client belongs. If the mgcp_client does
|
|
* not belong to a pool at all, the function call will have no effect. */
|
|
void mgcp_client_pool_put(struct mgcp_client *mgcp_client)
|
|
{
|
|
struct mgcp_client_pool_member *pool_member;
|
|
struct mgcp_client_pool *pool;
|
|
|
|
if (!mgcp_client)
|
|
return;
|
|
|
|
if (mgcp_client->pool)
|
|
pool = mgcp_client->pool;
|
|
else
|
|
return;
|
|
|
|
llist_for_each_entry(pool_member, &pool->pool, list) {
|
|
if (pool_member->client == mgcp_client) {
|
|
if (pool_member->refcount == 0) {
|
|
LOGP(DLMGCP, LOGL_ERROR, "MGW %u has invalid refcount\n", pool_member->nr);
|
|
return;
|
|
}
|
|
pool_member->refcount--;
|
|
}
|
|
}
|
|
}
|