Allow the query classifier to be specified in maxscale.cnf

query_classifier/query_classifier.cc

@@ -47,6 +47,7 @@ bool qc_init(const char* plugin_name)
 
     if (!plugin_name || (*plugin_name == 0))
     {
+        MXS_NOTICE("No query classifier specified, using default '%s'.", default_qc_name);
         plugin_name = default_qc_name;
     }
 

server/core/config.c

@@ -1002,6 +1002,22 @@ handle_global_item(const char *name, const char *value)
             MXS_ERROR("Invalid timeout value for 'auth_write_timeout': %s", value);
         }
     }
+    else if (strcmp(name, "query_classifier") == 0)
+    {
+        int len = strlen(value);
+        int max_len = sizeof(gateway.qc_name) - 1;
+
+        if (len <= max_len)
+        {
+            strcpy(gateway.qc_name, value);
+        }
+        else
+        {
+            MXS_ERROR("The length of '%s' is %d, while the maximum length is %d.",
+                      value, len, max_len);
+            return 0;
+        }
+    }
     else
     {
         for (i = 0; lognames[i].name; i++)
@@ -1110,6 +1126,9 @@ global_defaults()
     {
         strncpy(gateway.sysname, uname_data.sysname, _SYSNAME_STR_LENGTH);
     }
+
+    /* query_classifier */
+    memset(gateway.qc_name, 0, sizeof(gateway.qc_name));
 }
 
 /**

server/core/gateway.c

@@ -1782,7 +1782,10 @@ int main(int argc, char **argv)
         goto return_main;
     }
 
-    if (!qc_init(NULL))
+    GATEWAY_CONF* cnf = config_get_global_options();
+    ss_dassert(cnf);
+
+    if (!qc_init(cnf->qc_name))
     {
         char* logerr = "Failed to initialise query classifier library.";
         print_log_n_stderr(true, true, logerr, logerr, eno);

server/include/maxconfig.h

@@ -124,7 +124,8 @@ typedef struct
     int           log_to_shm;                          /**< Write log-file to shared memory */
     unsigned int  auth_conn_timeout;                   /**< Connection timeout for the user authentication */
     unsigned int  auth_read_timeout;                   /**< Read timeout for the user authentication */
-    unsigned int  auth_write_timeout;                  /**<  Write timeout for the user authentication */
+    unsigned int  auth_write_timeout;                  /**< Write timeout for the user authentication */
+    char          qc_name[PATH_MAX];                   /**< The name of the query classifier to load */
 } GATEWAY_CONF;