Hi,
It is to be expected. You need to synchronize your threads with a mutex. You
are changing len or pos at another part of the program and you violate the
assertion. Or better use gwlist_consume & gwlist_append, which lock pos.
BR,
Nikos
----- Original Message -----
From: Esteban Cacavelos
To: devel Devel
Sent: Thursday, January 28, 2010 8:02 PM
Subject: dbpool problem
Hi Developers, i've been prooving the dbpool of kannel in the following
scenario and i've found some problems
static DBPool *pool3 = NULL; //GLOBAL
//DATA BASE INIT
void voDBInitalization()
{
CfgGroup *grp;
Octstr *host, *username, *password, *database;
long port;
grp = cfg_get_single_group(cfg, octstr_imm("Database"));
if((host = cfg_get(grp, octstr_imm("Host")))==NULL)
panic(0, "Host");
if((username = cfg_get(grp, octstr_imm("User")))==NULL)
panic(0, "User");
if((password = cfg_get(grp, octstr_imm("Password")))==NULL)
panic(0, "passl");
if((database = cfg_get(grp, octstr_imm("DBName")))==NULL)
panic(0, "db");
if (cfg_get_integer(&port, grp, octstr_imm("Port")) == -1)
panic(0, "port");
db_conf = gw_malloc(sizeof(DBConf));
gw_assert(db_conf != NULL);
db_conf->mysql = gw_malloc(sizeof(MySQLConf));
gw_assert(db_conf->mysql != NULL);
db_conf->mysql->host = host;
db_conf->mysql->port = port;
db_conf->mysql->username = username;
db_conf->mysql->password = password;
db_conf->mysql->database = database;
pool = dbpool_create(DBPOOL_MYSQL, db_conf, 2);
gw_assert(pool != NULL);
}
//MAIN
int main (){
threads[j++] = gwthread_create(thread1,&stParam);
threads[j++] = gwthread_create(thread2,&stParam);
for (i = 0; i < j; ++i)
gwthread_join(threads[i]);
}
thread1 and thread2 share the pool and try the query when dbpool_check
returns >=1.
Both threads check the pool with dbpool_check(pool) and its works correctly
a few minutes but then the program throw panic because the function
dbpool_check call
pconn = gwlist_get(p->pool, i); AND THE FOLLOWING CONDITION DOESN'T MATCH
gw_assert(pos < list->len); in gwlist_get
I supose something like this is happening: one thread get the len of the
pool and then the other deletes one element when the dbpool_check try to
re-establish some connection, so, the first thread has a inconsitent len of the
pool.
i hope that i have explained the problem in the right way and sorry for the
mistakes.
--
Esteban L. Cacavelos de Amoriza
Cel: 0981 220 429
