Merge branch 'collectd-5.5' into collectd-5.6

[collectd.git] / src / python.c

diff --git a/src/python.c b/src/python.c
index 24046de..1a7359c 100644 (file)
--- a/src/python.c
+++ b/src/python.c
@@ -197,7 +197,7 @@ static char reg_flush_doc[] = "register_flush(callback[, data][, name]) -> ident
                "The callback function will be called with two or three parameters:\n"
                "timeout: Indicates that only data older than 'timeout' seconds is to\n"
                "    be flushed.\n"
-               "id: Specifies which values are to be flushed.\n"
+               "id: Specifies which values are to be flushed. Might be None.\n"
                "data: The optional data parameter passed to the register function.\n"
                "    If the parameter was omitted it will be omitted here, too.";
 
@@ -236,12 +236,23 @@ static cpy_callback_t *cpy_config_callbacks;
 static cpy_callback_t *cpy_init_callbacks;
 static cpy_callback_t *cpy_shutdown_callbacks;
 
+/* Make sure to hold the GIL while modifying these. */
+static int cpy_shutdown_triggered = 0;
+static int cpy_num_callbacks = 0;
+
 static void cpy_destroy_user_data(void *data) {
        cpy_callback_t *c = data;
        free(c->name);
+       CPY_LOCK_THREADS
        Py_DECREF(c->callback);
        Py_XDECREF(c->data);
        free(c);
+       --cpy_num_callbacks;
+       if (!cpy_num_callbacks && cpy_shutdown_triggered) {
+               Py_Finalize();
+               return;
+       }
+       CPY_RELEASE_THREADS
 }
 
 /* You must hold the GIL to call this function!
@@ -389,12 +400,11 @@ static int cpy_write_callback(const data_set_t *ds, const value_list_t *value_li
                }
                dict = PyDict_New();  /* New reference. */
                if (value_list->meta) {
-                       int num;
                        char **table;
                        meta_data_t *meta = value_list->meta;
 
-                       num = meta_data_toc(meta, &table);
-                       for (size_t i = 0; i < num; ++i) {
+                       int num = meta_data_toc(meta, &table);
+                       for (int i = 0; i < num; ++i) {
                                int type;
                                char *string;
                                int64_t si;
@@ -519,7 +529,12 @@ static void cpy_flush_callback(int timeout, const char *id, user_data_t *data) {
        PyObject *ret, *text;
 
        CPY_LOCK_THREADS
-       text = cpy_string_to_unicode_or_bytes(id);
+       if (id) {
+               text = cpy_string_to_unicode_or_bytes(id);
+       } else {
+               text = Py_None;
+               Py_INCREF(text);
+       }
        if (c->data == NULL)
                ret = PyObject_CallFunction(c->callback, "iN", timeout, text); /* New reference. */
        else
@@ -559,6 +574,7 @@ static PyObject *cpy_register_generic(cpy_callback_t **list_head, PyObject *args
        c->callback = callback;
        c->data = data;
        c->next = *list_head;
+       ++cpy_num_callbacks;
        *list_head = c;
        Py_XDECREF(mod);
        PyMem_Free(name);
@@ -624,7 +640,6 @@ static PyObject *cpy_register_generic_userdata(void *reg, void *handler, PyObjec
        char buf[512];
        reg_function_t *register_function = (reg_function_t *) reg;
        cpy_callback_t *c = NULL;
-       user_data_t user_data = { 0 };
        char *name = NULL;
        PyObject *callback = NULL, *data = NULL;
        static char *kwlist[] = {"callback", "data", "name", NULL};
@@ -650,17 +665,19 @@ static PyObject *cpy_register_generic_userdata(void *reg, void *handler, PyObjec
        c->data = data;
        c->next = NULL;
 
-       user_data.free_func = cpy_destroy_user_data;
-       user_data.data = c;
+       user_data_t user_data = {
+               .data = c,
+               .free_func = cpy_destroy_user_data
+       };
 
        register_function(buf, handler, &user_data);
+       ++cpy_num_callbacks;
        return cpy_string_to_unicode_or_bytes(buf);
 }
 
 static PyObject *cpy_register_read(PyObject *self, PyObject *args, PyObject *kwds) {
        char buf[512];
        cpy_callback_t *c = NULL;
-       user_data_t user_data = { 0 };
        double interval = 0;
        char *name = NULL;
        PyObject *callback = NULL, *data = NULL;
@@ -687,11 +704,14 @@ static PyObject *cpy_register_read(PyObject *self, PyObject *args, PyObject *kwd
        c->data = data;
        c->next = NULL;
 
-       user_data.free_func = cpy_destroy_user_data;
-       user_data.data = c;
+       user_data_t user_data = {
+               .data = c,
+               .free_func = cpy_destroy_user_data
+       };
 
        plugin_register_complex_read(/* group = */ "python", buf,
                        cpy_read_callback, DOUBLE_TO_CDTIME_T (interval), &user_data);
+       ++cpy_num_callbacks;
        return cpy_string_to_unicode_or_bytes(buf);
 }
 
@@ -797,8 +817,8 @@ static PyObject *cpy_unregister_generic(cpy_callback_t **list_head, PyObject *ar
                PyErr_Format(PyExc_RuntimeError, "Unable to unregister %s callback '%s'.", desc, name);
                return NULL;
        }
-       /* Yes, this is actually save. To call this function the caller has to
-        * hold the GIL. Well, save as long as there is only one GIL anyway ... */
+       /* Yes, this is actually safe. To call this function the caller has to
+        * hold the GIL. Well, safe as long as there is only one GIL anyway ... */
        if (prev == NULL)
                *list_head = tmp->next;
        else
@@ -807,6 +827,15 @@ static PyObject *cpy_unregister_generic(cpy_callback_t **list_head, PyObject *ar
        Py_RETURN_NONE;
 }
 
+static void cpy_unregister_list(cpy_callback_t **list_head) {
+       cpy_callback_t *cur, *next;
+       for (cur = *list_head; cur; cur = next) {
+               next = cur->next;
+               cpy_destroy_user_data(cur);
+       }
+       *list_head = NULL;
+}
+
 typedef int cpy_unregister_function_t(const char *name);
 
 static PyObject *cpy_unregister_generic_userdata(cpy_unregister_function_t *unreg, PyObject *arg, const char *desc) {
@@ -896,9 +925,7 @@ static PyMethodDef cpy_methods[] = {
 static int cpy_shutdown(void) {
        PyObject *ret;
 
-       /* This can happen if the module was loaded but not configured. */
-       if (state != NULL)
-               PyEval_RestoreThread(state);
+       PyEval_RestoreThread(state);
 
        for (cpy_callback_t *c = cpy_shutdown_callbacks; c; c = c->next) {
                ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
@@ -908,7 +935,15 @@ static int cpy_shutdown(void) {
                        Py_DECREF(ret);
        }
        PyErr_Print();
-       Py_Finalize();
+
+       cpy_unregister_list(&cpy_config_callbacks);
+       cpy_unregister_list(&cpy_init_callbacks);
+       cpy_unregister_list(&cpy_shutdown_callbacks);
+       cpy_shutdown_triggered = 1;
+
+       if (!cpy_num_callbacks)
+               Py_Finalize();
+
        return 0;
 }
 
@@ -941,7 +976,7 @@ static void *cpy_interactive(void *data) {
        if (PyImport_ImportModule("readline") == NULL) {
                /* This interactive session will suck. */
                cpy_log_exception("interactive session init");
-       }
+       }
        cur_sig = PyOS_setsig(SIGINT, python_sigint_handler);
        /* We totally forked just now. Everyone saw that, right? */
        PyOS_AfterFork();
@@ -961,6 +996,7 @@ static int cpy_init(void) {
        if (!Py_IsInitialized()) {
                WARNING("python: Plugin loaded but not configured.");
                plugin_unregister_shutdown("python");
+               Py_Finalize();
                return 0;
        }
        PyEval_InitThreads();