python: Fix memory leaks.
authorSven Trenkel <collectd@semidefinite.de>
Sun, 14 Oct 2012 15:12:45 +0000 (15:12 +0000)
committerSven Trenkel <collectd@semidefinite.de>
Sun, 14 Oct 2012 15:12:45 +0000 (15:12 +0000)
src/python.c
src/pyvalues.c

index cfc07f6..22f3db6 100644 (file)
@@ -282,17 +282,13 @@ void cpy_log_exception(const char *context) {
        Py_END_ALLOW_THREADS
        Py_XDECREF(tn);
        Py_XDECREF(m);
-       if (!cpy_format_exception) {
+       if (!cpy_format_exception || !traceback) {
                PyErr_Clear();
-               Py_XDECREF(type);
+               Py_DECREF(type);
                Py_XDECREF(value);
                Py_XDECREF(traceback);
                return;
        }
-       if (!traceback) {
-               PyErr_Clear();
-               return;
-       }
        list = PyObject_CallFunction(cpy_format_exception, "NNN", type, value, traceback); /* New reference. */
        if (list)
                l = PyObject_Length(list);
@@ -313,6 +309,9 @@ void cpy_log_exception(const char *context) {
        }
        Py_XDECREF(list);
        PyErr_Clear();
+       Py_DECREF(type);
+       Py_XDECREF(value);
+       Py_XDECREF(traceback);
 }
 
 static int cpy_read_callback(user_data_t *data) {
@@ -335,7 +334,7 @@ static int cpy_read_callback(user_data_t *data) {
 static int cpy_write_callback(const data_set_t *ds, const value_list_t *value_list, user_data_t *data) {
        int i;
        cpy_callback_t *c = data->data;
-       PyObject *ret, *list, *temp, *dict = NULL, *val;
+       PyObject *ret, *list, *temp, *dict = NULL;
        Values *v;
 
        CPY_LOCK_THREADS
@@ -375,7 +374,7 @@ static int cpy_write_callback(const data_set_t *ds, const value_list_t *value_li
                                CPY_RETURN_FROM_THREADS 0;
                        }
                }
-               dict = PyDict_New();
+               dict = PyDict_New();  /* New reference. */
                if (value_list->meta) {
                        int i, num;
                        char **table;
@@ -394,26 +393,26 @@ static int cpy_write_callback(const data_set_t *ds, const value_list_t *value_li
                                if (type == MD_TYPE_STRING) {
                                        if (meta_data_get_string(meta, table[i], &string))
                                                continue;
-                                       temp = cpy_string_to_unicode_or_bytes(string);
+                                       temp = cpy_string_to_unicode_or_bytes(string);  /* New reference. */
                                        free(string);
                                        PyDict_SetItemString(dict, table[i], temp);
                                        Py_XDECREF(temp);
                                } else if (type == MD_TYPE_SIGNED_INT) {
                                        if (meta_data_get_signed_int(meta, table[i], &si))
                                                continue;
-                                       temp = PyObject_CallFunctionObjArgs((void *) &SignedType, PyLong_FromLongLong(si), (void *) 0);
+                                       temp = PyObject_CallFunctionObjArgs((void *) &SignedType, PyLong_FromLongLong(si), (void *) 0);  /* New reference. */
                                        PyDict_SetItemString(dict, table[i], temp);
                                        Py_XDECREF(temp);
                                } else if (type == MD_TYPE_UNSIGNED_INT) {
                                        if (meta_data_get_unsigned_int(meta, table[i], &ui))
                                                continue;
-                                       temp = PyObject_CallFunctionObjArgs((void *) &UnsignedType, PyLong_FromUnsignedLongLong(ui), (void *) 0);
+                                       temp = PyObject_CallFunctionObjArgs((void *) &UnsignedType, PyLong_FromUnsignedLongLong(ui), (void *) 0);  /* New reference. */
                                        PyDict_SetItemString(dict, table[i], temp);
                                        Py_XDECREF(temp);
                                } else if (type == MD_TYPE_DOUBLE) {
                                        if (meta_data_get_double(meta, table[i], &d))
                                                continue;
-                                       temp = PyFloat_FromDouble(d);
+                                       temp = PyFloat_FromDouble(d);  /* New reference. */
                                        PyDict_SetItemString(dict, table[i], temp);
                                        Py_XDECREF(temp);
                                } else if (type == MD_TYPE_BOOLEAN) {
@@ -428,8 +427,7 @@ static int cpy_write_callback(const data_set_t *ds, const value_list_t *value_li
                        }
                        free(table);
                }
-               val = Values_New(); /* New reference. */
-               v = (Values *) val; 
+               v = (Values *) Values_New(); /* New reference. */
                sstrncpy(v->data.host, value_list->host, sizeof(v->data.host));
                sstrncpy(v->data.type, value_list->type, sizeof(v->data.type));
                sstrncpy(v->data.type_instance, value_list->type_instance, sizeof(v->data.type_instance));
@@ -440,9 +438,9 @@ static int cpy_write_callback(const data_set_t *ds, const value_list_t *value_li
                Py_CLEAR(v->values);
                v->values = list;
                Py_CLEAR(v->meta);
-               v->meta = dict;
+               v->meta = dict;  /* Steals a reference. */
                ret = PyObject_CallFunctionObjArgs(c->callback, v, c->data, (void *) 0); /* New reference. */
-               Py_XDECREF(val);
+               Py_XDECREF(v);
                if (ret == NULL) {
                        cpy_log_exception("write callback");
                } else {
@@ -484,11 +482,11 @@ static void cpy_log_callback(int severity, const char *message, user_data_t *dat
        PyObject *ret, *text;
 
        CPY_LOCK_THREADS
-       text = cpy_string_to_unicode_or_bytes(message);
+       text = cpy_string_to_unicode_or_bytes(message);  /* New reference. */
        if (c->data == NULL)
-               ret = PyObject_CallFunction(c->callback, "iN", severity, text); /* New reference. */
+               ret = PyObject_CallFunction(c->callback, "iN", severity, text); /* New reference. Steals a reference from "text". */
        else
-               ret = PyObject_CallFunction(c->callback, "iNO", severity, text, c->data); /* New reference. */
+               ret = PyObject_CallFunction(c->callback, "iNO", severity, text, c->data); /* New reference. Steals a reference from "text". */
 
        if (ret == NULL) {
                /* FIXME */
@@ -525,12 +523,13 @@ static void cpy_flush_callback(int timeout, const char *id, user_data_t *data) {
 static PyObject *cpy_register_generic(cpy_callback_t **list_head, PyObject *args, PyObject *kwds) {
        char buf[512];
        cpy_callback_t *c;
-       const char *name = NULL;
+       char *name = NULL;
        PyObject *callback = NULL, *data = NULL, *mod = NULL;
        static char *kwlist[] = {"callback", "data", "name", NULL};
        
        if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oet", kwlist, &callback, &data, NULL, &name) == 0) return NULL;
        if (PyCallable_Check(callback) == 0) {
+               PyMem_Free(name);
                PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
                return NULL;
        }
@@ -545,18 +544,21 @@ static PyObject *cpy_register_generic(cpy_callback_t **list_head, PyObject *args
        c->next = *list_head;
        *list_head = c;
        Py_XDECREF(mod);
+       PyMem_Free(name);
        return cpy_string_to_unicode_or_bytes(buf);
 }
 
 static PyObject *cpy_flush(cpy_callback_t **list_head, PyObject *args, PyObject *kwds) {
        int timeout = -1;
-       const char *plugin = NULL, *identifier = NULL;
+       char *plugin = NULL, *identifier = NULL;
        static char *kwlist[] = {"plugin", "timeout", "identifier", NULL};
        
        if (PyArg_ParseTupleAndKeywords(args, kwds, "|etiet", kwlist, NULL, &plugin, &timeout, NULL, &identifier) == 0) return NULL;
        Py_BEGIN_ALLOW_THREADS
        plugin_flush(plugin, timeout, identifier);
        Py_END_ALLOW_THREADS
+       PyMem_Free(plugin);
+       PyMem_Free(identifier);
        Py_RETURN_NONE;
 }
 
@@ -575,16 +577,18 @@ static PyObject *cpy_register_generic_userdata(void *reg, void *handler, PyObjec
        reg_function_t *register_function = (reg_function_t *) reg;
        cpy_callback_t *c = NULL;
        user_data_t *user_data = NULL;
-       const char *name = NULL;
+       char *name = NULL;
        PyObject *callback = NULL, *data = NULL;
        static char *kwlist[] = {"callback", "data", "name", NULL};
        
        if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oet", kwlist, &callback, &data, NULL, &name) == 0) return NULL;
        if (PyCallable_Check(callback) == 0) {
+               PyMem_Free(name);
                PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
                return NULL;
        }
        cpy_build_name(buf, sizeof(buf), callback, name);
+       PyMem_Free(name);
        
        Py_INCREF(callback);
        Py_XINCREF(data);
@@ -605,17 +609,19 @@ static PyObject *cpy_register_read(PyObject *self, PyObject *args, PyObject *kwd
        cpy_callback_t *c = NULL;
        user_data_t *user_data = NULL;
        double interval = 0;
-       const char *name = NULL;
+       char *name = NULL;
        PyObject *callback = NULL, *data = NULL;
        struct timespec ts;
        static char *kwlist[] = {"callback", "interval", "data", "name", NULL};
        
        if (PyArg_ParseTupleAndKeywords(args, kwds, "O|dOet", kwlist, &callback, &interval, &data, NULL, &name) == 0) return NULL;
        if (PyCallable_Check(callback) == 0) {
+               PyMem_Free(name);
                PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
                return NULL;
        }
        cpy_build_name(buf, sizeof(buf), callback, name);
+       PyMem_Free(name);
        
        Py_INCREF(callback);
        Py_XINCREF(data);
@@ -659,48 +665,53 @@ static PyObject *cpy_register_shutdown(PyObject *self, PyObject *args, PyObject
 }
 
 static PyObject *cpy_error(PyObject *self, PyObject *args) {
-       const char *text;
+       char *text;
        if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
        Py_BEGIN_ALLOW_THREADS
        plugin_log(LOG_ERR, "%s", text);
        Py_END_ALLOW_THREADS
+       PyMem_Free(text);
        Py_RETURN_NONE;
 }
 
 static PyObject *cpy_warning(PyObject *self, PyObject *args) {
-       const char *text;
+       char *text;
        if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
        Py_BEGIN_ALLOW_THREADS
        plugin_log(LOG_WARNING, "%s", text);
        Py_END_ALLOW_THREADS
+       PyMem_Free(text);
        Py_RETURN_NONE;
 }
 
 static PyObject *cpy_notice(PyObject *self, PyObject *args) {
-       const char *text;
+       char *text;
        if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
        Py_BEGIN_ALLOW_THREADS
        plugin_log(LOG_NOTICE, "%s", text);
        Py_END_ALLOW_THREADS
+       PyMem_Free(text);
        Py_RETURN_NONE;
 }
 
 static PyObject *cpy_info(PyObject *self, PyObject *args) {
-       const char *text;
+       char *text;
        if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
        Py_BEGIN_ALLOW_THREADS
        plugin_log(LOG_INFO, "%s", text);
        Py_END_ALLOW_THREADS
+       PyMem_Free(text);
        Py_RETURN_NONE;
 }
 
 static PyObject *cpy_debug(PyObject *self, PyObject *args) {
 #ifdef COLLECT_DEBUG
-       const char *text;
+       char *text;
        if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
        Py_BEGIN_ALLOW_THREADS
        plugin_log(LOG_DEBUG, "%s", text);
        Py_END_ALLOW_THREADS
+       PyMem_Free(text);
 #endif
        Py_RETURN_NONE;
 }
index 4a701d0..fd07882 100644 (file)
 
 #include "cpython.h"
 
+#define FreeAll() do {\
+       PyMem_Free(type);\
+       PyMem_Free(plugin_instance);\
+       PyMem_Free(type_instance);\
+       PyMem_Free(plugin);\
+       PyMem_Free(host);\
+} while(0)
+
 static PyObject *cpy_common_repr(PyObject *s) {
        PyObject *ret, *tmp;
        static PyObject *l_type = NULL, *l_type_instance = NULL, *l_plugin = NULL, *l_plugin_instance = NULL;
@@ -143,7 +151,7 @@ static PyObject *PluginData_new(PyTypeObject *type, PyObject *args, PyObject *kw
 static int PluginData_init(PyObject *s, PyObject *args, PyObject *kwds) {
        PluginData *self = (PluginData *) s;
        double time = 0;
-       const char *type = "", *plugin_instance = "", *type_instance = "", *plugin = "", *host = "";
+       char *type = NULL, *plugin_instance = NULL, *type_instance = NULL, *plugin = NULL, *host = NULL;
        static char *kwlist[] = {"type", "plugin_instance", "type_instance",
                        "plugin", "host", "time", NULL};
        
@@ -151,18 +159,21 @@ static int PluginData_init(PyObject *s, PyObject *args, PyObject *kwds) {
                        NULL, &plugin_instance, NULL, &type_instance, NULL, &plugin, NULL, &host, &time))
                return -1;
        
-       if (type[0] != 0 && plugin_get_ds(type) == NULL) {
+       if (type && plugin_get_ds(type) == NULL) {
                PyErr_Format(PyExc_TypeError, "Dataset %s not found", type);
+               FreeAll();
                return -1;
        }
 
-       sstrncpy(self->host, host, sizeof(self->host));
-       sstrncpy(self->plugin, plugin, sizeof(self->plugin));
-       sstrncpy(self->plugin_instance, plugin_instance, sizeof(self->plugin_instance));
-       sstrncpy(self->type, type, sizeof(self->type));
-       sstrncpy(self->type_instance, type_instance, sizeof(self->type_instance));
-       
+       sstrncpy(self->host, host ? host : "", sizeof(self->host));
+       sstrncpy(self->plugin, plugin ? plugin : "", sizeof(self->plugin));
+       sstrncpy(self->plugin_instance, plugin_instance ? plugin_instance : "", sizeof(self->plugin_instance));
+       sstrncpy(self->type, type ? type : "", sizeof(self->type));
+       sstrncpy(self->type_instance, type_instance ? type_instance : "", sizeof(self->type_instance));
        self->time = time;
+
+       FreeAll();
+
        return 0;
 }
 
@@ -354,7 +365,7 @@ static int Values_init(PyObject *s, PyObject *args, PyObject *kwds) {
        int interval = 0;
        double time = 0;
        PyObject *values = NULL, *meta = NULL, *tmp;
-       const char *type = "", *plugin_instance = "", *type_instance = "", *plugin = "", *host = "";
+       char *type = NULL, *plugin_instance = NULL, *type_instance = NULL, *plugin = NULL, *host = NULL;
        static char *kwlist[] = {"type", "values", "plugin_instance", "type_instance",
                        "plugin", "host", "time", "interval", "meta", NULL};
        
@@ -363,18 +374,21 @@ static int Values_init(PyObject *s, PyObject *args, PyObject *kwds) {
                        NULL, &plugin, NULL, &host, &time, &interval, &meta))
                return -1;
        
-       if (type[0] != 0 && plugin_get_ds(type) == NULL) {
+       if (type && plugin_get_ds(type) == NULL) {
                PyErr_Format(PyExc_TypeError, "Dataset %s not found", type);
+               FreeAll();
                return -1;
        }
 
-       sstrncpy(self->data.host, host, sizeof(self->data.host));
-       sstrncpy(self->data.plugin, plugin, sizeof(self->data.plugin));
-       sstrncpy(self->data.plugin_instance, plugin_instance, sizeof(self->data.plugin_instance));
-       sstrncpy(self->data.type, type, sizeof(self->data.type));
-       sstrncpy(self->data.type_instance, type_instance, sizeof(self->data.type_instance));
+       sstrncpy(self->data.host, host ? host : "", sizeof(self->data.host));
+       sstrncpy(self->data.plugin, plugin ? plugin : "", sizeof(self->data.plugin));
+       sstrncpy(self->data.plugin_instance, plugin_instance ? plugin_instance : "", sizeof(self->data.plugin_instance));
+       sstrncpy(self->data.type, type ? type : "", sizeof(self->data.type));
+       sstrncpy(self->data.type_instance, type_instance ? type_instance : "", sizeof(self->data.type_instance));
        self->data.time = time;
 
+       FreeAll();
+
        if (values == NULL) {
                values = PyList_New(0);
                PyErr_Clear();
@@ -492,11 +506,7 @@ static PyObject *Values_dispatch(Values *self, PyObject *args, PyObject *kwds) {
        PyObject *values = self->values, *meta = self->meta;
        double time = self->data.time;
        int interval = self->interval;
-       const char *host = self->data.host;
-       const char *plugin = self->data.plugin;
-       const char *plugin_instance = self->data.plugin_instance;
-       const char *type = self->data.type;
-       const char *type_instance = self->data.type_instance;
+       char *host = NULL, *plugin = NULL, *plugin_instance = NULL, *type = NULL, *type_instance = NULL;
        
        static char *kwlist[] = {"type", "values", "plugin_instance", "type_instance",
                        "plugin", "host", "time", "interval", "meta", NULL};
@@ -505,13 +515,20 @@ static PyObject *Values_dispatch(Values *self, PyObject *args, PyObject *kwds) {
                        NULL, &plugin, NULL, &host, &time, &interval, &meta))
                return NULL;
 
-       if (type[0] == 0) {
+       sstrncpy(value_list.host, host ? host : self->data.host, sizeof(value_list.host));
+       sstrncpy(value_list.plugin, plugin ? plugin : self->data.plugin, sizeof(value_list.plugin));
+       sstrncpy(value_list.plugin_instance, plugin_instance ? plugin_instance : self->data.plugin_instance, sizeof(value_list.plugin_instance));
+       sstrncpy(value_list.type, type ? type : self->data.type, sizeof(value_list.type));
+       sstrncpy(value_list.type_instance, type_instance ? type_instance : self->data.type_instance, sizeof(value_list.type_instance));
+       FreeAll();
+       if (value_list.type[0] == 0) {
                PyErr_SetString(PyExc_RuntimeError, "type not set");
+               FreeAll();
                return NULL;
        }
-       ds = plugin_get_ds(type);
+       ds = plugin_get_ds(value_list.type);
        if (ds == NULL) {
-               PyErr_Format(PyExc_TypeError, "Dataset %s not found", type);
+               PyErr_Format(PyExc_TypeError, "Dataset %s not found", value_list.type);
                return NULL;
        }
        if (values == NULL || (PyTuple_Check(values) == 0 && PyList_Check(values) == 0)) {
@@ -524,7 +541,7 @@ static PyObject *Values_dispatch(Values *self, PyObject *args, PyObject *kwds) {
        }
        size = (int) PySequence_Length(values);
        if (size != ds->ds_num) {
-               PyErr_Format(PyExc_RuntimeError, "type %s needs %d values, got %i", type, ds->ds_num, size);
+               PyErr_Format(PyExc_RuntimeError, "type %s needs %d values, got %i", value_list.type, ds->ds_num, size);
                return NULL;
        }
        value = malloc(size * sizeof(*value));
@@ -561,7 +578,7 @@ static PyObject *Values_dispatch(Values *self, PyObject *args, PyObject *kwds) {
                        }
                } else {
                        free(value);
-                       PyErr_Format(PyExc_RuntimeError, "unknown data type %d for %s", ds->ds->type, type);
+                       PyErr_Format(PyExc_RuntimeError, "unknown data type %d for %s", ds->ds->type, value_list.type);
                        return NULL;
                }
                if (PyErr_Occurred() != NULL) {
@@ -574,11 +591,6 @@ static PyObject *Values_dispatch(Values *self, PyObject *args, PyObject *kwds) {
        value_list.values_len = size;
        value_list.time = time;
        value_list.interval = interval;
-       sstrncpy(value_list.host, host, sizeof(value_list.host));
-       sstrncpy(value_list.plugin, plugin, sizeof(value_list.plugin));
-       sstrncpy(value_list.plugin_instance, plugin_instance, sizeof(value_list.plugin_instance));
-       sstrncpy(value_list.type, type, sizeof(value_list.type));
-       sstrncpy(value_list.type_instance, type_instance, sizeof(value_list.type_instance));
        if (value_list.host[0] == 0)
                sstrncpy(value_list.host, hostname_g, sizeof(value_list.host));
        if (value_list.plugin[0] == 0)
@@ -604,27 +616,28 @@ static PyObject *Values_write(Values *self, PyObject *args, PyObject *kwds) {
        PyObject *values = self->values, *meta = self->meta;
        double time = self->data.time;
        int interval = self->interval;
-       const char *host = self->data.host;
-       const char *plugin = self->data.plugin;
-       const char *plugin_instance = self->data.plugin_instance;
-       const char *type = self->data.type;
-       const char *type_instance = self->data.type_instance;
-       const char *dest = NULL;
+       char *host = NULL, *plugin = NULL, *plugin_instance = NULL, *type = NULL, *type_instance = NULL, *dest = NULL;
        
        static char *kwlist[] = {"destination", "type", "values", "plugin_instance", "type_instance",
                        "plugin", "host", "time", "interval", "meta", NULL};
-       if (!PyArg_ParseTupleAndKeywords(args, kwds, "|etOetetetetdiO", kwlist,
+       if (!PyArg_ParseTupleAndKeywords(args, kwds, "et|etOetetetetdiO", kwlist, NULL, &dest,
                        NULL, &type, &values, NULL, &plugin_instance, NULL, &type_instance,
                        NULL, &plugin, NULL, &host, &time, &interval, &meta))
                return NULL;
 
-       if (type[0] == 0) {
+       sstrncpy(value_list.host, host ? host : self->data.host, sizeof(value_list.host));
+       sstrncpy(value_list.plugin, plugin ? plugin : self->data.plugin, sizeof(value_list.plugin));
+       sstrncpy(value_list.plugin_instance, plugin_instance ? plugin_instance : self->data.plugin_instance, sizeof(value_list.plugin_instance));
+       sstrncpy(value_list.type, type ? type : self->data.type, sizeof(value_list.type));
+       sstrncpy(value_list.type_instance, type_instance ? type_instance : self->data.type_instance, sizeof(value_list.type_instance));
+       FreeAll();
+       if (value_list.type[0] == 0) {
                PyErr_SetString(PyExc_RuntimeError, "type not set");
                return NULL;
        }
-       ds = plugin_get_ds(type);
+       ds = plugin_get_ds(value_list.type);
        if (ds == NULL) {
-               PyErr_Format(PyExc_TypeError, "Dataset %s not found", type);
+               PyErr_Format(PyExc_TypeError, "Dataset %s not found", value_list.type);
                return NULL;
        }
        if (values == NULL || (PyTuple_Check(values) == 0 && PyList_Check(values) == 0)) {
@@ -633,7 +646,7 @@ static PyObject *Values_write(Values *self, PyObject *args, PyObject *kwds) {
        }
        size = (int) PySequence_Length(values);
        if (size != ds->ds_num) {
-               PyErr_Format(PyExc_RuntimeError, "type %s needs %d values, got %i", type, ds->ds_num, size);
+               PyErr_Format(PyExc_RuntimeError, "type %s needs %d values, got %i", value_list.type, ds->ds_num, size);
                return NULL;
        }
        value = malloc(size * sizeof(*value));
@@ -670,7 +683,7 @@ static PyObject *Values_write(Values *self, PyObject *args, PyObject *kwds) {
                        }
                } else {
                        free(value);
-                       PyErr_Format(PyExc_RuntimeError, "unknown data type %d for %s", ds->ds->type, type);
+                       PyErr_Format(PyExc_RuntimeError, "unknown data type %d for %s", ds->ds->type, value_list.type);
                        return NULL;
                }
                if (PyErr_Occurred() != NULL) {
@@ -682,11 +695,6 @@ static PyObject *Values_write(Values *self, PyObject *args, PyObject *kwds) {
        value_list.values_len = size;
        value_list.time = time;
        value_list.interval = interval;
-       sstrncpy(value_list.host, host, sizeof(value_list.host));
-       sstrncpy(value_list.plugin, plugin, sizeof(value_list.plugin));
-       sstrncpy(value_list.plugin_instance, plugin_instance, sizeof(value_list.plugin_instance));
-       sstrncpy(value_list.type, type, sizeof(value_list.type));
-       sstrncpy(value_list.type_instance, type_instance, sizeof(value_list.type_instance));
        value_list.meta = cpy_build_meta(meta);;
        if (value_list.host[0] == 0)
                sstrncpy(value_list.host, hostname_g, sizeof(value_list.host));
@@ -830,8 +838,8 @@ static int Notification_init(PyObject *s, PyObject *args, PyObject *kwds) {
        Notification *self = (Notification *) s;
        int severity = 0;
        double time = 0;
-       const char *message = "";
-       const char *type = "", *plugin_instance = "", *type_instance = "", *plugin = "", *host = "";
+       char *message = NULL;
+       char *type = NULL, *plugin_instance = NULL, *type_instance = NULL, *plugin = NULL, *host = NULL;
        static char *kwlist[] = {"type", "message", "plugin_instance", "type_instance",
                        "plugin", "host", "time", "severity", NULL};
        
@@ -840,20 +848,24 @@ static int Notification_init(PyObject *s, PyObject *args, PyObject *kwds) {
                        NULL, &plugin, NULL, &host, &time, &severity))
                return -1;
        
-       if (type[0] != 0 && plugin_get_ds(type) == NULL) {
+       if (type && plugin_get_ds(type) == NULL) {
                PyErr_Format(PyExc_TypeError, "Dataset %s not found", type);
+               FreeAll();
+               PyMem_Free(message);
                return -1;
        }
 
-       sstrncpy(self->data.host, host, sizeof(self->data.host));
-       sstrncpy(self->data.plugin, plugin, sizeof(self->data.plugin));
-       sstrncpy(self->data.plugin_instance, plugin_instance, sizeof(self->data.plugin_instance));
-       sstrncpy(self->data.type, type, sizeof(self->data.type));
-       sstrncpy(self->data.type_instance, type_instance, sizeof(self->data.type_instance));
+       sstrncpy(self->data.host, host ? host : "", sizeof(self->data.host));
+       sstrncpy(self->data.plugin, plugin ? plugin : "", sizeof(self->data.plugin));
+       sstrncpy(self->data.plugin_instance, plugin_instance ? plugin_instance : "", sizeof(self->data.plugin_instance));
+       sstrncpy(self->data.type, type ? type : "", sizeof(self->data.type));
+       sstrncpy(self->data.type_instance, type_instance ? type_instance : "", sizeof(self->data.type_instance));
+       sstrncpy(self->message, message ? message : "", sizeof(self->message));
        self->data.time = time;
-
-       sstrncpy(self->message, message, sizeof(self->message));
        self->severity = severity;
+
+       FreeAll();
+       PyMem_Free(message);
        return 0;
 }
 
@@ -863,12 +875,8 @@ static PyObject *Notification_dispatch(Notification *self, PyObject *args, PyObj
        notification_t notification;
        double t = self->data.time;
        int severity = self->severity;
-       const char *host = self->data.host;
-       const char *plugin = self->data.plugin;
-       const char *plugin_instance = self->data.plugin_instance;
-       const char *type = self->data.type;
-       const char *type_instance = self->data.type_instance;
-       const char *message = self->message;
+       char *host = NULL, *plugin = NULL, *plugin_instance = NULL, *type = NULL, *type_instance = NULL;
+       char *message = NULL;
        
        static char *kwlist[] = {"type", "message", "plugin_instance", "type_instance",
                        "plugin", "host", "time", "severity", NULL};
@@ -877,25 +885,28 @@ static PyObject *Notification_dispatch(Notification *self, PyObject *args, PyObj
                        NULL, &plugin, NULL, &host, &t, &severity))
                return NULL;
 
-       if (type[0] == 0) {
+       notification.time = t;
+       notification.severity = severity;
+       sstrncpy(notification.message, message ? message : self->message, sizeof(notification.message));
+       sstrncpy(notification.host, host ? host : self->data.host, sizeof(notification.host));
+       sstrncpy(notification.plugin, plugin ? plugin : self->data.plugin, sizeof(notification.plugin));
+       sstrncpy(notification.plugin_instance, plugin_instance ? plugin_instance : self->data.plugin_instance, sizeof(notification.plugin_instance));
+       sstrncpy(notification.type, type ? type : self->data.type, sizeof(notification.type));
+       sstrncpy(notification.type_instance, type_instance ? type_instance : self->data.type_instance, sizeof(notification.type_instance));
+       notification.meta = NULL;
+       FreeAll();
+       PyMem_Free(message);
+
+       if (notification.type[0] == 0) {
                PyErr_SetString(PyExc_RuntimeError, "type not set");
                return NULL;
        }
-       ds = plugin_get_ds(type);
+       ds = plugin_get_ds(notification.type);
        if (ds == NULL) {
-               PyErr_Format(PyExc_TypeError, "Dataset %s not found", type);
+               PyErr_Format(PyExc_TypeError, "Dataset %s not found", notification.type);
                return NULL;
        }
 
-       notification.time = t;
-       notification.severity = severity;
-       sstrncpy(notification.message, message, sizeof(notification.message));
-       sstrncpy(notification.host, host, sizeof(notification.host));
-       sstrncpy(notification.plugin, plugin, sizeof(notification.plugin));
-       sstrncpy(notification.plugin_instance, plugin_instance, sizeof(notification.plugin_instance));
-       sstrncpy(notification.type, type, sizeof(notification.type));
-       sstrncpy(notification.type_instance, type_instance, sizeof(notification.type_instance));
-       notification.meta = NULL;
        if (notification.time < 1)
                notification.time = time(0);
        if (notification.host[0] == 0)