MXS-1929: Initialize filter in filter_alloc

Changed the filter_alloc function to fully initialize the filter. This
means that if filter_alloc returns a non-NULL pointer, the filter was
successfully loaded and an instance was successfully created.

server/core/filter.cc

@@ -58,6 +58,14 @@ static void filter_free_parameters(MXS_FILTER_DEF *filter);
  */
 MXS_FILTER_DEF* filter_alloc(const char *name, const char *module, MXS_CONFIG_PARAMETER* params)
 {
+    MXS_FILTER_OBJECT* object = (MXS_FILTER_OBJECT*)load_module(module, MODULE_FILTER);
+
+    if (object == NULL)
+    {
+        MXS_ERROR("Failed to load filter module '%s'.", module);
+        return NULL;
+    }
+
     char* my_name = MXS_STRDUP(name);
     char* my_module = MXS_STRDUP(module);
 
@@ -72,8 +80,7 @@ MXS_FILTER_DEF* filter_alloc(const char *name, const char *module, MXS_CONFIG_PA
     }
     filter->name = my_name;
     filter->module = my_module;
-    filter->filter = NULL;
+    filter->obj = object;
-    filter->obj = NULL;
     filter->parameters = NULL;
     spinlock_init(&filter->spin);
 
@@ -82,6 +89,16 @@ MXS_FILTER_DEF* filter_alloc(const char *name, const char *module, MXS_CONFIG_PA
         filter_add_parameter(filter, p->name, p->value);
     }
 
+    if ((filter->filter = object->createInstance(name, params)) == NULL)
+    {
+        MXS_ERROR("Failed to create filter '%s' instance.", name);
+        filter_free_parameters(filter);
+        MXS_FREE(my_name);
+        MXS_FREE(my_module);
+        MXS_FREE(filter);
+        return NULL;
+    }
+
     spinlock_acquire(&filter_spin);
     filter->next = allFilters;
     allFilters = filter;
@@ -306,51 +323,6 @@ static void filter_free_parameters(MXS_FILTER_DEF *filter)
     config_parameter_free(filter->parameters);
 }
 
-/**
- * Load a filter module for use and create an instance of it for a service.
- * @param filter Filter definition
- * @return True if module was successfully loaded, false if an error occurred
- */
-bool filter_load(MXS_FILTER_DEF* filter)
-{
-    bool rval = false;
-    if (filter)
-    {
-        if (filter->filter)
-        {
-            // Already loaded and created.
-            rval = true;
-        }
-        else
-        {
-            if (filter->obj == NULL)
-            {
-                /* Filter not yet loaded */
-                if ((filter->obj = (MXS_FILTER_OBJECT*)load_module(filter->module, MODULE_FILTER)) == NULL)
-                {
-                    MXS_ERROR("Failed to load filter module '%s'.", filter->module);
-                }
-            }
-
-            if (filter->obj)
-            {
-                ss_dassert(!filter->filter);
-
-                if ((filter->filter = (filter->obj->createInstance)(filter->name,
-                                                                    filter->parameters)))
-                {
-                    rval = true;
-                }
-                else
-                {
-                    MXS_ERROR("Failed to create filter '%s' instance.", filter->name);
-                }
-            }
-        }
-    }
-    return rval;
-}
-
 /**
  * Connect the downstream filter chain for a filter.
  *

server/core/internal/filter.h

@@ -40,7 +40,6 @@ void filter_add_parameter(MXS_FILTER_DEF *filter_def, const char *name, const ch
 MXS_FILTER_DEF *filter_alloc(const char *name, const char *module, MXS_CONFIG_PARAMETER* params);
 MXS_DOWNSTREAM *filter_apply(MXS_FILTER_DEF *filter_def, MXS_SESSION *session, MXS_DOWNSTREAM *downstream);
 void filter_free(MXS_FILTER_DEF *filter_def);
-bool filter_load(MXS_FILTER_DEF *filter_def);
 int filter_standard_parameter(const char *name);
 MXS_UPSTREAM *filter_upstream(MXS_FILTER_DEF *filter_def,
                               MXS_FILTER_SESSION *fsession,

server/core/service.cc

@@ -1251,8 +1251,6 @@ bool service_set_filters(SERVICE* service, const char* filters)
         fix_object_name(&f[0]);
 
         if (MXS_FILTER_DEF* def = filter_def_find(f.c_str()))
-        {
-            if (filter_load(def))
         {
             flist.push_back(def);
 
@@ -1266,12 +1264,6 @@ bool service_set_filters(SERVICE* service, const char* filters)
             }
         }
         else
-            {
-                MXS_ERROR("Failed to load filter '%s' for service '%s'.", f.c_str(), service->name);
-                rval = false;
-            }
-        }
-        else
         {
             MXS_ERROR("Unable to find filter '%s' for service '%s'", f.c_str(), service->name);
             rval = false;

server/core/test/test_filter.cc

@@ -33,6 +33,9 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include <maxscale/alloc.h>
+#include <maxscale/paths.h>
+
 #include "../internal/filter.h"
 
 
@@ -45,7 +48,7 @@ test1()
 {
     MXS_FILTER_DEF  *f1, *f2;
 
-    if ((f1 = filter_alloc("test1", "module", NULL)) == NULL)
+    if ((f1 = filter_alloc("test1", "qlafilter", NULL)) == NULL)
     {
         fprintf(stderr, "filter_alloc: test 1 failed.\n");
         return 1;
@@ -78,7 +81,7 @@ test2()
 {
     MXS_FILTER_DEF  *f1;
 
-    if ((f1 = filter_alloc("test1", "module", NULL)) == NULL)
+    if ((f1 = filter_alloc("test1", "qlafilter", NULL)) == NULL)
     {
         fprintf(stderr, "filter_alloc: test 1 failed.\n");
         return 1;
@@ -106,7 +109,7 @@ test3()
     for (i = 0; i < n_filters; i++)
     {
         sprintf(name, "filter%d", i);
-        if ((f1 = filter_alloc(name, "module", NULL)) == NULL)
+        if ((f1 = filter_alloc(name, "qlafilter", NULL)) == NULL)
         {
             fprintf(stderr,
                     "filter_alloc: test 3 failed with %s.\n", name);
@@ -146,6 +149,7 @@ int
 main(int argc, char **argv)
 {
     int result = 0;
+    set_libdir(MXS_STRDUP_A("../../modules/filter/qlafilter/"));
 
     result += test1();
     result += test2();