mysql plugin: Don't give up when connecting to the database fails during `init'.

Instead a connection attempt is made in increasing intervals, up to one day.

diff --git a/src/mysql.c b/src/mysql.c
index 822c6cc..caebdf3 100644 (file)
--- a/src/mysql.c
+++ b/src/mysql.c
@@ -44,10 +44,6 @@ static char *user;
 static char *pass;
 static char *db = NULL;
 
-#if MYSQL_HAVE_READ
-static char  init_suceeded = 0;
-#endif
-
 /* TODO
  * understand `Select_*' and possibly do that stuff as well..
  */
@@ -117,6 +113,11 @@ static MYSQL *getconnection (void)
        static MYSQL *con;
        static int    state;
 
+       static int wait_for = 0;
+       static int wait_increase = 60;
+
+       int step;
+
        if (state != 0)
        {
                int err;
@@ -132,6 +133,19 @@ static MYSQL *getconnection (void)
                }
        }
 
+       step = atoi (COLLECTD_STEP);
+
+       if (wait_for > 0)
+       {
+               wait_for -= step;
+               return (NULL);
+       }
+
+       wait_for = wait_increase;
+       wait_increase *= 2;
+       if (wait_increase > 86400)
+               wait_increase = 86400;
+
        if ((con = mysql_init (con)) == NULL)
        {
                syslog (LOG_ERR, "mysql_init failed: %s", mysql_error (con));
@@ -148,6 +162,8 @@ static MYSQL *getconnection (void)
        else
        {
                state = 1;
+               wait_for = 0;
+               wait_increase = 60;
                return (con);
        }
 } /* static MYSQL *getconnection (void) */
@@ -155,16 +171,6 @@ static MYSQL *getconnection (void)
 
 static void init (void)
 {
-#if MYSQL_HAVE_READ
-       if (getconnection () != NULL)
-               init_suceeded = 1;
-       else
-       {
-               syslog (LOG_ERR, "The `mysql' plugin will be disabled because `init' failed to connect to `%s'", host);
-               init_suceeded = 0;
-       }
-#endif /* MYSQL_HAVE_READ */
-
        return;
 }
 
@@ -358,9 +364,6 @@ static void mysql_read (void)
        unsigned long long traffic_incoming = 0ULL;
        unsigned long long traffic_outgoing = 0ULL;
 
-       if (init_suceeded == 0)
-               return;
-
        /* An error message will have been printed in this case */
        if ((con = getconnection ()) == NULL)
                return;