1 /**
2 * collectd - src/python.c
3 * Copyright (C) 2009 Sven Trenkel
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 *
23 * Authors:
24 * Sven Trenkel <collectd at semidefinite.de>
25 **/
27 #include <Python.h>
28 #include <structmember.h>
30 #include <signal.h>
31 #if HAVE_PTHREAD_H
32 # include <pthread.h>
33 #endif
35 #include "collectd.h"
36 #include "common.h"
38 #include "cpython.h"
40 typedef struct cpy_callback_s {
41 char *name;
42 PyObject *callback;
43 PyObject *data;
44 struct cpy_callback_s *next;
45 } cpy_callback_t;
47 static char log_doc[] = "This function sends a string to all logging plugins.";
49 static char flush_doc[] = "flush([plugin][, timeout][, identifier]) -> None\n"
50 "\n"
51 "Flushes the cache of another plugin.";
53 static char unregister_doc[] = "Unregisters a callback. This function needs exactly one parameter either\n"
54 "the function to unregister or the callback identifier to unregister.";
56 static char reg_log_doc[] = "register_log(callback[, data][, name]) -> identifier\n"
57 "\n"
58 "Register a callback function for log messages.\n"
59 "\n"
60 "'callback' is a callable object that will be called every time something\n"
61 " is logged.\n"
62 "'data' is an optional object that will be passed back to the callback\n"
63 " function every time it is called.\n"
64 "'name' is an optional identifier for this callback. The default name\n"
65 " is 'python.<module>'.\n"
66 " Every callback needs a unique identifier, so if you want to\n"
67 " register this callback multiple time from the same module you need\n"
68 " to specify a name here.\n"
69 "'identifier' is the full identifier assigned to this callback.\n"
70 "\n"
71 "The callback function will be called with two or three parameters:\n"
72 "severity: An integer that should be compared to the LOG_ constants.\n"
73 "message: The text to be logged.\n"
74 "data: The optional data parameter passed to the register function.\n"
75 " If the parameter was omitted it will be omitted here, too.";
77 static char reg_init_doc[] = "register_init(callback[, data][, name]) -> identifier\n"
78 "\n"
79 "Register a callback function that will be executed once after the config.\n"
80 "file has been read, all plugins heve been loaded and the collectd has\n"
81 "forked into the background.\n"
82 "\n"
83 "'callback' is a callable object that will be executed.\n"
84 "'data' is an optional object that will be passed back to the callback\n"
85 " function when it is called.\n"
86 "'name' is an optional identifier for this callback. The default name\n"
87 " is 'python.<module>'.\n"
88 " Every callback needs a unique identifier, so if you want to\n"
89 " register this callback multiple time from the same module you need\n"
90 " to specify a name here.\n"
91 "'identifier' is the full identifier assigned to this callback.\n"
92 "\n"
93 "The callback function will be called without parameters, except for\n"
94 "data if it was supplied.";
96 static char reg_config_doc[] = "register_config(callback[, data][, name]) -> identifier\n"
97 "\n"
98 "Register a callback function for config file entries.\n"
99 "'callback' is a callable object that will be called for every config block.\n"
100 "'data' is an optional object that will be passed back to the callback\n"
101 " function every time it is called.\n"
102 "'name' is an optional identifier for this callback. The default name\n"
103 " is 'python.<module>'.\n"
104 " Every callback needs a unique identifier, so if you want to\n"
105 " register this callback multiple time from the same module you need\n"
106 " to specify a name here.\n"
107 "'identifier' is the full identifier assigned to this callback.\n"
108 "\n"
109 "The callback function will be called with one or two parameters:\n"
110 "config: A Config object.\n"
111 "data: The optional data parameter passed to the register function.\n"
112 " If the parameter was omitted it will be omitted here, too.";
114 static char reg_read_doc[] = "register_read(callback[, interval][, data][, name]) -> identifier\n"
115 "\n"
116 "Register a callback function for reading data. It will just be called\n"
117 "in a fixed interval to signal that it's time to dispatch new values.\n"
118 "'callback' is a callable object that will be called every time something\n"
119 " is logged.\n"
120 "'interval' is the number of seconds between between calls to the callback\n"
121 " function. Full float precision is supported here.\n"
122 "'data' is an optional object that will be passed back to the callback\n"
123 " function every time it is called.\n"
124 "'name' is an optional identifier for this callback. The default name\n"
125 " is 'python.<module>'.\n"
126 " Every callback needs a unique identifier, so if you want to\n"
127 " register this callback multiple time from the same module you need\n"
128 " to specify a name here.\n"
129 "'identifier' is the full identifier assigned to this callback.\n"
130 "\n"
131 "The callback function will be called without parameters, except for\n"
132 "data if it was supplied.";
134 static char reg_write_doc[] = "register_write(callback[, data][, name]) -> identifier\n"
135 "\n"
136 "Register a callback function to receive values dispatched by other plugins.\n"
137 "'callback' is a callable object that will be called every time a value\n"
138 " is dispatched.\n"
139 "'data' is an optional object that will be passed back to the callback\n"
140 " function every time it is called.\n"
141 "'name' is an optional identifier for this callback. The default name\n"
142 " is 'python.<module>'.\n"
143 " Every callback needs a unique identifier, so if you want to\n"
144 " register this callback multiple time from the same module you need\n"
145 " to specify a name here.\n"
146 "'identifier' is the full identifier assigned to this callback.\n"
147 "\n"
148 "The callback function will be called with one or two parameters:\n"
149 "values: A Values object which is a copy of the dispatched values.\n"
150 "data: The optional data parameter passed to the register function.\n"
151 " If the parameter was omitted it will be omitted here, too.";
153 static char reg_notification_doc[] = "register_notification(callback[, data][, name]) -> identifier\n"
154 "\n"
155 "Register a callback function for notifications.\n"
156 "'callback' is a callable object that will be called every time a notification\n"
157 " is dispatched.\n"
158 "'data' is an optional object that will be passed back to the callback\n"
159 " function every time it is called.\n"
160 "'name' is an optional identifier for this callback. The default name\n"
161 " is 'python.<module>'.\n"
162 " Every callback needs a unique identifier, so if you want to\n"
163 " register this callback multiple time from the same module you need\n"
164 " to specify a name here.\n"
165 "'identifier' is the full identifier assigned to this callback.\n"
166 "\n"
167 "The callback function will be called with one or two parameters:\n"
168 "notification: A copy of the notification that was dispatched.\n"
169 "data: The optional data parameter passed to the register function.\n"
170 " If the parameter was omitted it will be omitted here, too.";
172 static char reg_flush_doc[] = "register_flush(callback[, data][, name]) -> identifier\n"
173 "\n"
174 "Register a callback function for flush messages.\n"
175 "'callback' is a callable object that will be called every time a plugin\n"
176 " requests a flush for either this or all plugins.\n"
177 "'data' is an optional object that will be passed back to the callback\n"
178 " function every time it is called.\n"
179 "'name' is an optional identifier for this callback. The default name\n"
180 " is 'python.<module>'.\n"
181 " Every callback needs a unique identifier, so if you want to\n"
182 " register this callback multiple time from the same module you need\n"
183 " to specify a name here.\n"
184 "'identifier' is the full identifier assigned to this callback.\n"
185 "\n"
186 "The callback function will be called with two or three parameters:\n"
187 "timeout: Indicates that only data older than 'timeout' seconds is to\n"
188 " be flushed.\n"
189 "id: Specifies which values are to be flushed.\n"
190 "data: The optional data parameter passed to the register function.\n"
191 " If the parameter was omitted it will be omitted here, too.";
193 static char reg_shutdown_doc[] = "register_shutdown(callback[, data][, name]) -> identifier\n"
194 "\n"
195 "Register a callback function for collectd shutdown.\n"
196 "'callback' is a callable object that will be called once collectd is\n"
197 " shutting down.\n"
198 "'data' is an optional object that will be passed back to the callback\n"
199 " function if it is called.\n"
200 "'name' is an optional identifier for this callback. The default name\n"
201 " is 'python.<module>'.\n"
202 " Every callback needs a unique identifier, so if you want to\n"
203 " register this callback multiple time from the same module you need\n"
204 " to specify a name here.\n"
205 "'identifier' is the full identifier assigned to this callback.\n"
206 "\n"
207 "The callback function will be called with no parameters except for\n"
208 " data if it was supplied.";
211 static int do_interactive = 0;
213 /* This is our global thread state. Python saves some stuff in thread-local
214 * storage. So if we allow the interpreter to run in the background
215 * (the scriptwriters might have created some threads from python), we have
216 * to save the state so we can resume it later after shutdown. */
218 static PyThreadState *state;
220 static PyObject *cpy_format_exception;
222 static cpy_callback_t *cpy_config_callbacks;
223 static cpy_callback_t *cpy_init_callbacks;
224 static cpy_callback_t *cpy_shutdown_callbacks;
226 static void cpy_destroy_user_data(void *data) {
227 cpy_callback_t *c = data;
228 free(c->name);
229 Py_DECREF(c->callback);
230 Py_XDECREF(c->data);
231 free(c);
232 }
234 /* You must hold the GIL to call this function!
235 * But if you managed to extract the callback parameter then you probably already do. */
237 static void cpy_build_name(char *buf, size_t size, PyObject *callback, const char *name) {
238 const char *module = NULL;
239 PyObject *mod = NULL;
241 if (name != NULL) {
242 snprintf(buf, size, "python.%s", name);
243 return;
244 }
246 mod = PyObject_GetAttrString(callback, "__module__"); /* New reference. */
247 if (mod != NULL)
248 module = cpy_unicode_or_bytes_to_string(&mod);
250 if (module != NULL) {
251 snprintf(buf, size, "python.%s", module);
252 Py_XDECREF(mod);
253 PyErr_Clear();
254 return;
255 }
256 Py_XDECREF(mod);
258 snprintf(buf, size, "python.%p", callback);
259 PyErr_Clear();
260 }
262 static void cpy_log_exception(const char *context) {
263 int l = 0, i;
264 const char *typename = NULL, *message = NULL;
265 PyObject *type, *value, *traceback, *tn, *m, *list;
267 PyErr_Fetch(&type, &value, &traceback);
268 PyErr_NormalizeException(&type, &value, &traceback);
269 if (type == NULL) return;
270 tn = PyObject_GetAttrString(type, "__name__"); /* New reference. */
271 m = PyObject_Str(value); /* New reference. */
272 if (tn != NULL)
273 typename = cpy_unicode_or_bytes_to_string(&tn);
274 if (m != NULL)
275 message = cpy_unicode_or_bytes_to_string(&m);
276 if (typename == NULL)
277 typename = "NamelessException";
278 if (message == NULL)
279 message = "N/A";
280 Py_BEGIN_ALLOW_THREADS
281 ERROR("Unhandled python exception in %s: %s: %s", context, typename, message);
282 Py_END_ALLOW_THREADS
283 Py_XDECREF(tn);
284 Py_XDECREF(m);
285 if (!cpy_format_exception) {
286 PyErr_Clear();
287 Py_XDECREF(type);
288 Py_XDECREF(value);
289 Py_XDECREF(traceback);
290 return;
291 }
292 if (!traceback) {
293 PyErr_Clear();
294 return;
295 }
296 list = PyObject_CallFunction(cpy_format_exception, "NNN", type, value, traceback); /* New reference. */
297 if (list)
298 l = PyObject_Length(list);
299 for (i = 0; i < l; ++i) {
300 char *s;
301 PyObject *line;
303 line = PyList_GET_ITEM(list, i); /* Borrowed reference. */
304 Py_INCREF(line);
305 s = strdup(cpy_unicode_or_bytes_to_string(&line));
306 Py_DECREF(line);
307 if (s[strlen(s) - 1] == '\n')
308 s[strlen(s) - 1] = 0;
309 Py_BEGIN_ALLOW_THREADS
310 ERROR("%s", s);
311 Py_END_ALLOW_THREADS
312 free(s);
313 }
314 Py_XDECREF(list);
315 PyErr_Clear();
316 }
318 static int cpy_read_callback(user_data_t *data) {
319 cpy_callback_t *c = data->data;
320 PyObject *ret;
322 CPY_LOCK_THREADS
323 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
324 if (ret == NULL) {
325 cpy_log_exception("read callback");
326 } else {
327 Py_DECREF(ret);
328 }
329 CPY_RELEASE_THREADS
330 if (ret == NULL)
331 return 1;
332 return 0;
333 }
335 static int cpy_write_callback(const data_set_t *ds, const value_list_t *value_list, user_data_t *data) {
336 int i;
337 cpy_callback_t *c = data->data;
338 PyObject *ret, *list;
339 Values *v;
341 CPY_LOCK_THREADS
342 list = PyList_New(value_list->values_len); /* New reference. */
343 if (list == NULL) {
344 cpy_log_exception("write callback");
345 CPY_RETURN_FROM_THREADS 0;
346 }
347 for (i = 0; i < value_list->values_len; ++i) {
348 if (ds->ds->type == DS_TYPE_COUNTER) {
349 if ((long) value_list->values[i].counter == value_list->values[i].counter)
350 PyList_SetItem(list, i, PyInt_FromLong(value_list->values[i].counter));
351 else
352 PyList_SetItem(list, i, PyLong_FromUnsignedLongLong(value_list->values[i].counter));
353 } else if (ds->ds->type == DS_TYPE_GAUGE) {
354 PyList_SetItem(list, i, PyFloat_FromDouble(value_list->values[i].gauge));
355 } else if (ds->ds->type == DS_TYPE_DERIVE) {
356 if ((long) value_list->values[i].derive == value_list->values[i].derive)
357 PyList_SetItem(list, i, PyInt_FromLong(value_list->values[i].derive));
358 else
359 PyList_SetItem(list, i, PyLong_FromLongLong(value_list->values[i].derive));
360 } else if (ds->ds->type == DS_TYPE_ABSOLUTE) {
361 if ((long) value_list->values[i].absolute == value_list->values[i].absolute)
362 PyList_SetItem(list, i, PyInt_FromLong(value_list->values[i].absolute));
363 else
364 PyList_SetItem(list, i, PyLong_FromUnsignedLongLong(value_list->values[i].absolute));
365 } else {
366 Py_BEGIN_ALLOW_THREADS
367 ERROR("cpy_write_callback: Unknown value type %d.", ds->ds->type);
368 Py_END_ALLOW_THREADS
369 Py_DECREF(list);
370 CPY_RETURN_FROM_THREADS 0;
371 }
372 if (PyErr_Occurred() != NULL) {
373 cpy_log_exception("value building for write callback");
374 CPY_RETURN_FROM_THREADS 0;
375 }
376 }
377 v = PyObject_New(Values, (void *) &ValuesType);
378 sstrncpy(v->data.host, value_list->host, sizeof(v->data.host));
379 sstrncpy(v->data.type, value_list->type, sizeof(v->data.type));
380 sstrncpy(v->data.type_instance, value_list->type_instance, sizeof(v->data.type_instance));
381 sstrncpy(v->data.plugin, value_list->plugin, sizeof(v->data.plugin));
382 sstrncpy(v->data.plugin_instance, value_list->plugin_instance, sizeof(v->data.plugin_instance));
383 v->data.time = value_list->time;
384 v->interval = value_list->interval;
385 v->values = list;
386 ret = PyObject_CallFunctionObjArgs(c->callback, v, c->data, (void *) 0); /* New reference. */
387 if (ret == NULL) {
388 cpy_log_exception("write callback");
389 } else {
390 Py_DECREF(ret);
391 }
392 CPY_RELEASE_THREADS
393 return 0;
394 }
396 static int cpy_notification_callback(const notification_t *notification, user_data_t *data) {
397 cpy_callback_t *c = data->data;
398 PyObject *ret;
399 Notification *n;
401 CPY_LOCK_THREADS
402 n = PyObject_New(Notification, (void *) &NotificationType);
403 sstrncpy(n->data.host, notification->host, sizeof(n->data.host));
404 sstrncpy(n->data.type, notification->type, sizeof(n->data.type));
405 sstrncpy(n->data.type_instance, notification->type_instance, sizeof(n->data.type_instance));
406 sstrncpy(n->data.plugin, notification->plugin, sizeof(n->data.plugin));
407 sstrncpy(n->data.plugin_instance, notification->plugin_instance, sizeof(n->data.plugin_instance));
408 n->data.time = notification->time;
409 sstrncpy(n->message, notification->message, sizeof(n->message));
410 n->severity = notification->severity;
411 ret = PyObject_CallFunctionObjArgs(c->callback, n, c->data, (void *) 0); /* New reference. */
412 if (ret == NULL) {
413 cpy_log_exception("notification callback");
414 } else {
415 Py_DECREF(ret);
416 }
417 CPY_RELEASE_THREADS
418 return 0;
419 }
421 static void cpy_log_callback(int severity, const char *message, user_data_t *data) {
422 cpy_callback_t * c = data->data;
423 PyObject *ret, *text;
425 CPY_LOCK_THREADS
426 text = cpy_string_to_unicode_or_bytes(message);
427 if (c->data == NULL)
428 ret = PyObject_CallFunction(c->callback, "iN", severity, text); /* New reference. */
429 else
430 ret = PyObject_CallFunction(c->callback, "iNO", severity, text, c->data); /* New reference. */
432 if (ret == NULL) {
433 /* FIXME */
434 /* Do we really want to trigger a log callback because a log callback failed?
435 * Probably not. */
436 PyErr_Print();
437 /* In case someone wanted to be clever, replaced stderr and failed at that. */
438 PyErr_Clear();
439 } else {
440 Py_DECREF(ret);
441 }
442 CPY_RELEASE_THREADS
443 }
445 static void cpy_flush_callback(int timeout, const char *id, user_data_t *data) {
446 cpy_callback_t * c = data->data;
447 PyObject *ret, *text;
449 CPY_LOCK_THREADS
450 text = cpy_string_to_unicode_or_bytes(id);
451 if (c->data == NULL)
452 ret = PyObject_CallFunction(c->callback, "iN", timeout, text); /* New reference. */
453 else
454 ret = PyObject_CallFunction(c->callback, "iNO", timeout, text, c->data); /* New reference. */
456 if (ret == NULL) {
457 cpy_log_exception("flush callback");
458 } else {
459 Py_DECREF(ret);
460 }
461 CPY_RELEASE_THREADS
462 }
464 static PyObject *cpy_register_generic(cpy_callback_t **list_head, PyObject *args, PyObject *kwds) {
465 char buf[512];
466 cpy_callback_t *c;
467 const char *name = NULL;
468 PyObject *callback = NULL, *data = NULL, *mod = NULL;
469 static char *kwlist[] = {"callback", "data", "name", NULL};
471 if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oet", kwlist, &callback, &data, NULL, &name) == 0) return NULL;
472 if (PyCallable_Check(callback) == 0) {
473 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
474 return NULL;
475 }
476 cpy_build_name(buf, sizeof(buf), callback, name);
478 Py_INCREF(callback);
479 Py_XINCREF(data);
480 c = malloc(sizeof(*c));
481 c->name = strdup(buf);
482 c->callback = callback;
483 c->data = data;
484 c->next = *list_head;
485 *list_head = c;
486 Py_XDECREF(mod);
487 return cpy_string_to_unicode_or_bytes(buf);
488 }
490 static PyObject *cpy_flush(cpy_callback_t **list_head, PyObject *args, PyObject *kwds) {
491 int timeout = -1;
492 const char *plugin = NULL, *identifier = NULL;
493 static char *kwlist[] = {"plugin", "timeout", "identifier", NULL};
495 if (PyArg_ParseTupleAndKeywords(args, kwds, "|etiet", kwlist, NULL, &plugin, &timeout, NULL, &identifier) == 0) return NULL;
496 Py_BEGIN_ALLOW_THREADS
497 plugin_flush(plugin, timeout, identifier);
498 Py_END_ALLOW_THREADS
499 Py_RETURN_NONE;
500 }
502 static PyObject *cpy_register_config(PyObject *self, PyObject *args, PyObject *kwds) {
503 return cpy_register_generic(&cpy_config_callbacks, args, kwds);
504 }
506 static PyObject *cpy_register_init(PyObject *self, PyObject *args, PyObject *kwds) {
507 return cpy_register_generic(&cpy_init_callbacks, args, kwds);
508 }
510 typedef int reg_function_t(const char *name, void *callback, void *data);
512 static PyObject *cpy_register_generic_userdata(void *reg, void *handler, PyObject *args, PyObject *kwds) {
513 char buf[512];
514 reg_function_t *register_function = (reg_function_t *) reg;
515 cpy_callback_t *c = NULL;
516 user_data_t *user_data = NULL;
517 const char *name = NULL;
518 PyObject *callback = NULL, *data = NULL;
519 static char *kwlist[] = {"callback", "data", "name", NULL};
521 if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oet", kwlist, &callback, &data, NULL, &name) == 0) return NULL;
522 if (PyCallable_Check(callback) == 0) {
523 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
524 return NULL;
525 }
526 cpy_build_name(buf, sizeof(buf), callback, name);
528 Py_INCREF(callback);
529 Py_XINCREF(data);
530 c = malloc(sizeof(*c));
531 c->name = strdup(buf);
532 c->callback = callback;
533 c->data = data;
534 c->next = NULL;
535 user_data = malloc(sizeof(*user_data));
536 user_data->free_func = cpy_destroy_user_data;
537 user_data->data = c;
538 register_function(buf, handler, user_data);
539 return cpy_string_to_unicode_or_bytes(buf);
540 }
542 static PyObject *cpy_register_read(PyObject *self, PyObject *args, PyObject *kwds) {
543 char buf[512];
544 cpy_callback_t *c = NULL;
545 user_data_t *user_data = NULL;
546 double interval = 0;
547 const char *name = NULL;
548 PyObject *callback = NULL, *data = NULL;
549 struct timespec ts;
550 static char *kwlist[] = {"callback", "interval", "data", "name", NULL};
552 if (PyArg_ParseTupleAndKeywords(args, kwds, "O|dOet", kwlist, &callback, &interval, &data, NULL, &name) == 0) return NULL;
553 if (PyCallable_Check(callback) == 0) {
554 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
555 return NULL;
556 }
557 cpy_build_name(buf, sizeof(buf), callback, name);
559 Py_INCREF(callback);
560 Py_XINCREF(data);
561 c = malloc(sizeof(*c));
562 c->name = strdup(buf);
563 c->callback = callback;
564 c->data = data;
565 c->next = NULL;
566 user_data = malloc(sizeof(*user_data));
567 user_data->free_func = cpy_destroy_user_data;
568 user_data->data = c;
569 ts.tv_sec = interval;
570 ts.tv_nsec = (interval - ts.tv_sec) * 1000000000;
571 plugin_register_complex_read(buf, cpy_read_callback, &ts, user_data);
572 return cpy_string_to_unicode_or_bytes(buf);
573 }
575 static PyObject *cpy_register_log(PyObject *self, PyObject *args, PyObject *kwds) {
576 return cpy_register_generic_userdata((void *) plugin_register_log,
577 (void *) cpy_log_callback, args, kwds);
578 }
580 static PyObject *cpy_register_write(PyObject *self, PyObject *args, PyObject *kwds) {
581 return cpy_register_generic_userdata((void *) plugin_register_write,
582 (void *) cpy_write_callback, args, kwds);
583 }
585 static PyObject *cpy_register_notification(PyObject *self, PyObject *args, PyObject *kwds) {
586 return cpy_register_generic_userdata((void *) plugin_register_notification,
587 (void *) cpy_notification_callback, args, kwds);
588 }
590 static PyObject *cpy_register_flush(PyObject *self, PyObject *args, PyObject *kwds) {
591 return cpy_register_generic_userdata((void *) plugin_register_flush,
592 (void *) cpy_flush_callback, args, kwds);
593 }
595 static PyObject *cpy_register_shutdown(PyObject *self, PyObject *args, PyObject *kwds) {
596 return cpy_register_generic(&cpy_shutdown_callbacks, args, kwds);
597 }
599 static PyObject *cpy_error(PyObject *self, PyObject *args) {
600 const char *text;
601 if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
602 Py_BEGIN_ALLOW_THREADS
603 plugin_log(LOG_ERR, "%s", text);
604 Py_END_ALLOW_THREADS
605 Py_RETURN_NONE;
606 }
608 static PyObject *cpy_warning(PyObject *self, PyObject *args) {
609 const char *text;
610 if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
611 Py_BEGIN_ALLOW_THREADS
612 plugin_log(LOG_WARNING, "%s", text);
613 Py_END_ALLOW_THREADS
614 Py_RETURN_NONE;
615 }
617 static PyObject *cpy_notice(PyObject *self, PyObject *args) {
618 const char *text;
619 if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
620 Py_BEGIN_ALLOW_THREADS
621 plugin_log(LOG_NOTICE, "%s", text);
622 Py_END_ALLOW_THREADS
623 Py_RETURN_NONE;
624 }
626 static PyObject *cpy_info(PyObject *self, PyObject *args) {
627 const char *text;
628 if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
629 Py_BEGIN_ALLOW_THREADS
630 plugin_log(LOG_INFO, "%s", text);
631 Py_END_ALLOW_THREADS
632 Py_RETURN_NONE;
633 }
635 static PyObject *cpy_debug(PyObject *self, PyObject *args) {
636 #ifdef COLLECT_DEBUG
637 const char *text;
638 if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
639 Py_BEGIN_ALLOW_THREADS
640 plugin_log(LOG_DEBUG, "%s", text);
641 Py_END_ALLOW_THREADS
642 #endif
643 Py_RETURN_NONE;
644 }
646 static PyObject *cpy_unregister_generic(cpy_callback_t **list_head, PyObject *arg, const char *desc) {
647 char buf[512];
648 const char *name;
649 cpy_callback_t *prev = NULL, *tmp;
651 Py_INCREF(arg);
652 name = cpy_unicode_or_bytes_to_string(&arg);
653 if (name == NULL) {
654 PyErr_Clear();
655 if (!PyCallable_Check(arg)) {
656 PyErr_SetString(PyExc_TypeError, "This function needs a string or a callable object as its only parameter.");
657 Py_DECREF(arg);
658 return NULL;
659 }
660 cpy_build_name(buf, sizeof(buf), arg, NULL);
661 name = buf;
662 }
663 for (tmp = *list_head; tmp; prev = tmp, tmp = tmp->next)
664 if (strcmp(name, tmp->name) == 0)
665 break;
667 Py_DECREF(arg);
668 if (tmp == NULL) {
669 PyErr_Format(PyExc_RuntimeError, "Unable to unregister %s callback '%s'.", desc, name);
670 return NULL;
671 }
672 /* Yes, this is actually save. To call this function the caller has to
673 * hold the GIL. Well, save as long as there is only one GIL anyway ... */
674 if (prev == NULL)
675 *list_head = tmp->next;
676 else
677 prev->next = tmp->next;
678 cpy_destroy_user_data(tmp);
679 Py_RETURN_NONE;
680 }
682 typedef int cpy_unregister_function_t(const char *name);
684 static PyObject *cpy_unregister_generic_userdata(cpy_unregister_function_t *unreg, PyObject *arg, const char *desc) {
685 char buf[512];
686 const char *name;
688 Py_INCREF(arg);
689 name = cpy_unicode_or_bytes_to_string(&arg);
690 if (name == NULL) {
691 PyErr_Clear();
692 if (!PyCallable_Check(arg)) {
693 PyErr_SetString(PyExc_TypeError, "This function needs a string or a callable object as its only parameter.");
694 Py_DECREF(arg);
695 return NULL;
696 }
697 cpy_build_name(buf, sizeof(buf), arg, NULL);
698 name = buf;
699 }
700 if (unreg(name) == 0) {
701 Py_DECREF(arg);
702 Py_RETURN_NONE;
703 }
704 PyErr_Format(PyExc_RuntimeError, "Unable to unregister %s callback '%s'.", desc, name);
705 Py_DECREF(arg);
706 return NULL;
707 }
709 static PyObject *cpy_unregister_log(PyObject *self, PyObject *arg) {
710 return cpy_unregister_generic_userdata(plugin_unregister_log, arg, "log");
711 }
713 static PyObject *cpy_unregister_init(PyObject *self, PyObject *arg) {
714 return cpy_unregister_generic(&cpy_init_callbacks, arg, "init");
715 }
717 static PyObject *cpy_unregister_config(PyObject *self, PyObject *arg) {
718 return cpy_unregister_generic(&cpy_config_callbacks, arg, "config");
719 }
721 static PyObject *cpy_unregister_read(PyObject *self, PyObject *arg) {
722 return cpy_unregister_generic_userdata(plugin_unregister_read, arg, "read");
723 }
725 static PyObject *cpy_unregister_write(PyObject *self, PyObject *arg) {
726 return cpy_unregister_generic_userdata(plugin_unregister_write, arg, "write");
727 }
729 static PyObject *cpy_unregister_notification(PyObject *self, PyObject *arg) {
730 return cpy_unregister_generic_userdata(plugin_unregister_notification, arg, "notification");
731 }
733 static PyObject *cpy_unregister_flush(PyObject *self, PyObject *arg) {
734 return cpy_unregister_generic_userdata(plugin_unregister_flush, arg, "flush");
735 }
737 static PyObject *cpy_unregister_shutdown(PyObject *self, PyObject *arg) {
738 return cpy_unregister_generic(&cpy_shutdown_callbacks, arg, "shutdown");
739 }
741 static PyMethodDef cpy_methods[] = {
742 {"debug", cpy_debug, METH_VARARGS, log_doc},
743 {"info", cpy_info, METH_VARARGS, log_doc},
744 {"notice", cpy_notice, METH_VARARGS, log_doc},
745 {"warning", cpy_warning, METH_VARARGS, log_doc},
746 {"error", cpy_error, METH_VARARGS, log_doc},
747 {"flush", (PyCFunction) cpy_flush, METH_VARARGS | METH_KEYWORDS, flush_doc},
748 {"register_log", (PyCFunction) cpy_register_log, METH_VARARGS | METH_KEYWORDS, reg_log_doc},
749 {"register_init", (PyCFunction) cpy_register_init, METH_VARARGS | METH_KEYWORDS, reg_init_doc},
750 {"register_config", (PyCFunction) cpy_register_config, METH_VARARGS | METH_KEYWORDS, reg_config_doc},
751 {"register_read", (PyCFunction) cpy_register_read, METH_VARARGS | METH_KEYWORDS, reg_read_doc},
752 {"register_write", (PyCFunction) cpy_register_write, METH_VARARGS | METH_KEYWORDS, reg_write_doc},
753 {"register_notification", (PyCFunction) cpy_register_notification, METH_VARARGS | METH_KEYWORDS, reg_notification_doc},
754 {"register_flush", (PyCFunction) cpy_register_flush, METH_VARARGS | METH_KEYWORDS, reg_flush_doc},
755 {"register_shutdown", (PyCFunction) cpy_register_shutdown, METH_VARARGS | METH_KEYWORDS, reg_shutdown_doc},
756 {"unregister_log", cpy_unregister_log, METH_O, unregister_doc},
757 {"unregister_init", cpy_unregister_init, METH_O, unregister_doc},
758 {"unregister_config", cpy_unregister_config, METH_O, unregister_doc},
759 {"unregister_read", cpy_unregister_read, METH_O, unregister_doc},
760 {"unregister_write", cpy_unregister_write, METH_O, unregister_doc},
761 {"unregister_notification", cpy_unregister_notification, METH_O, unregister_doc},
762 {"unregister_flush", cpy_unregister_flush, METH_O, unregister_doc},
763 {"unregister_shutdown", cpy_unregister_shutdown, METH_O, unregister_doc},
764 {0, 0, 0, 0}
765 };
767 static int cpy_shutdown(void) {
768 cpy_callback_t *c;
769 PyObject *ret;
771 /* This can happen if the module was loaded but not configured. */
772 if (state != NULL)
773 PyEval_RestoreThread(state);
775 for (c = cpy_shutdown_callbacks; c; c = c->next) {
776 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
777 if (ret == NULL)
778 cpy_log_exception("shutdown callback");
779 else
780 Py_DECREF(ret);
781 }
782 PyErr_Print();
783 Py_Finalize();
784 return 0;
785 }
787 static void cpy_int_handler(int sig) {
788 return;
789 }
791 static void *cpy_interactive(void *data) {
792 sigset_t sigset;
793 struct sigaction sig_int_action, old;
795 /* Signal handler in a plugin? Bad stuff, but the best way to
796 * handle it I guess. In an interactive session people will
797 * press Ctrl+C at some time, which will generate a SIGINT.
798 * This will cause collectd to shutdown, thus killing the
799 * interactive interpreter, and leaving the terminal in a
800 * mess. Chances are, this isn't what the user wanted to do.
801 *
802 * So this is the plan:
803 * 1. Block SIGINT in the main thread.
804 * 2. Install our own signal handler that does nothing.
805 * 3. Unblock SIGINT in the interactive thread.
806 *
807 * This will make sure that SIGINT won't kill collectd but
808 * still interrupt syscalls like sleep and pause.
809 * It does not raise a KeyboardInterrupt exception because so
810 * far nobody managed to figure out how to do that. */
811 memset (&sig_int_action, '\0', sizeof (sig_int_action));
812 sig_int_action.sa_handler = cpy_int_handler;
813 sigaction (SIGINT, &sig_int_action, &old);
815 sigemptyset(&sigset);
816 sigaddset(&sigset, SIGINT);
817 pthread_sigmask(SIG_UNBLOCK, &sigset, NULL);
818 PyEval_AcquireThread(state);
819 if (PyImport_ImportModule("readline") == NULL) {
820 /* This interactive session will suck. */
821 cpy_log_exception("interactive session init");
822 }
823 PyRun_InteractiveLoop(stdin, "<stdin>");
824 PyErr_Print();
825 PyEval_ReleaseThread(state);
826 NOTICE("python: Interactive interpreter exited, stopping collectd ...");
827 /* Restore the original collectd SIGINT handler and raise SIGINT.
828 * The main thread still has SIGINT blocked and there's nothing we
829 * can do about that so this thread will handle it. But that's not
830 * important, except that it won't interrupt the main loop and so
831 * it might take a few seconds before collectd really shuts down. */
832 sigaction (SIGINT, &old, NULL);
833 raise(SIGINT);
834 pause();
835 return NULL;
836 }
838 static int cpy_init(void) {
839 cpy_callback_t *c;
840 PyObject *ret;
841 static pthread_t thread;
842 sigset_t sigset;
844 PyEval_InitThreads();
845 /* Now it's finally OK to use python threads. */
846 for (c = cpy_init_callbacks; c; c = c->next) {
847 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
848 if (ret == NULL)
849 cpy_log_exception("init callback");
850 else
851 Py_DECREF(ret);
852 }
853 sigemptyset(&sigset);
854 sigaddset(&sigset, SIGINT);
855 pthread_sigmask(SIG_BLOCK, &sigset, NULL);
856 state = PyEval_SaveThread();
857 if (do_interactive) {
858 if (pthread_create(&thread, NULL, cpy_interactive, NULL)) {
859 ERROR("python: Error creating thread for interactive interpreter.");
860 }
861 }
863 return 0;
864 }
866 static PyObject *cpy_oconfig_to_pyconfig(oconfig_item_t *ci, PyObject *parent) {
867 int i;
868 PyObject *item, *values, *children, *tmp;
870 if (parent == NULL)
871 parent = Py_None;
873 values = PyTuple_New(ci->values_num); /* New reference. */
874 for (i = 0; i < ci->values_num; ++i) {
875 if (ci->values[i].type == OCONFIG_TYPE_STRING) {
876 PyTuple_SET_ITEM(values, i, cpy_string_to_unicode_or_bytes(ci->values[i].value.string));
877 } else if (ci->values[i].type == OCONFIG_TYPE_NUMBER) {
878 PyTuple_SET_ITEM(values, i, PyFloat_FromDouble(ci->values[i].value.number));
879 } else if (ci->values[i].type == OCONFIG_TYPE_BOOLEAN) {
880 PyTuple_SET_ITEM(values, i, PyBool_FromLong(ci->values[i].value.boolean));
881 }
882 }
884 tmp = cpy_string_to_unicode_or_bytes(ci->key);
885 item = PyObject_CallFunction((void *) &ConfigType, "NONO", tmp, parent, values, Py_None);
886 if (item == NULL)
887 return NULL;
888 children = PyTuple_New(ci->children_num); /* New reference. */
889 for (i = 0; i < ci->children_num; ++i) {
890 PyTuple_SET_ITEM(children, i, cpy_oconfig_to_pyconfig(ci->children + i, item));
891 }
892 tmp = ((Config *) item)->children;
893 ((Config *) item)->children = children;
894 Py_XDECREF(tmp);
895 return item;
896 }
898 #ifdef IS_PY3K
899 static struct PyModuleDef collectdmodule = {
900 PyModuleDef_HEAD_INIT,
901 "collectd", /* name of module */
902 "The python interface to collectd", /* module documentation, may be NULL */
903 -1,
904 cpy_methods
905 };
907 PyMODINIT_FUNC PyInit_collectd(void) {
908 return PyModule_Create(&collectdmodule);
909 }
910 #endif
912 static int cpy_config(oconfig_item_t *ci) {
913 int i;
914 PyObject *sys, *tb;
915 PyObject *sys_path;
916 PyObject *module;
918 /* Ok in theory we shouldn't do initialization at this point
919 * but we have to. In order to give python scripts a chance
920 * to register a config callback we need to be able to execute
921 * python code during the config callback so we have to start
922 * the interpreter here. */
923 /* Do *not* use the python "thread" module at this point! */
925 #ifdef IS_PY3K
926 /* Add a builtin module, before Py_Initialize */
927 PyImport_AppendInittab("collectd", PyInit_collectd);
928 #endif
930 Py_Initialize();
932 PyType_Ready(&ConfigType);
933 PyType_Ready(&PluginDataType);
934 ValuesType.tp_base = &PluginDataType;
935 PyType_Ready(&ValuesType);
936 NotificationType.tp_base = &PluginDataType;
937 PyType_Ready(&NotificationType);
938 sys = PyImport_ImportModule("sys"); /* New reference. */
939 if (sys == NULL) {
940 cpy_log_exception("python initialization");
941 return 1;
942 }
943 sys_path = PyObject_GetAttrString(sys, "path"); /* New reference. */
944 Py_DECREF(sys);
945 if (sys_path == NULL) {
946 cpy_log_exception("python initialization");
947 return 1;
948 }
949 #ifdef IS_PY3K
950 module = PyImport_ImportModule("collectd");
951 #else
952 module = Py_InitModule("collectd", cpy_methods); /* Borrowed reference. */
953 #endif
954 PyModule_AddObject(module, "Config", (void *) &ConfigType); /* Steals a reference. */
955 PyModule_AddObject(module, "Values", (void *) &ValuesType); /* Steals a reference. */
956 PyModule_AddObject(module, "Notification", (void *) &NotificationType); /* Steals a reference. */
957 PyModule_AddIntConstant(module, "LOG_DEBUG", LOG_DEBUG);
958 PyModule_AddIntConstant(module, "LOG_INFO", LOG_INFO);
959 PyModule_AddIntConstant(module, "LOG_NOTICE", LOG_NOTICE);
960 PyModule_AddIntConstant(module, "LOG_WARNING", LOG_WARNING);
961 PyModule_AddIntConstant(module, "LOG_ERROR", LOG_ERR);
962 PyModule_AddIntConstant(module, "NOTIF_FAILURE", NOTIF_FAILURE);
963 PyModule_AddIntConstant(module, "NOTIF_WARNING", NOTIF_WARNING);
964 PyModule_AddIntConstant(module, "NOTIF_OKAY", NOTIF_OKAY);
965 for (i = 0; i < ci->children_num; ++i) {
966 oconfig_item_t *item = ci->children + i;
968 if (strcasecmp(item->key, "Interactive") == 0) {
969 if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_BOOLEAN)
970 continue;
971 do_interactive = item->values[0].value.boolean;
972 } else if (strcasecmp(item->key, "Encoding") == 0) {
973 if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_STRING)
974 continue;
975 /* Why is this even necessary? And undocumented? */
976 if (PyUnicode_SetDefaultEncoding(item->values[0].value.string))
977 cpy_log_exception("setting default encoding");
978 } else if (strcasecmp(item->key, "LogTraces") == 0) {
979 if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_BOOLEAN)
980 continue;
981 if (!item->values[0].value.boolean) {
982 Py_XDECREF(cpy_format_exception);
983 cpy_format_exception = NULL;
984 continue;
985 }
986 if (cpy_format_exception)
987 continue;
988 tb = PyImport_ImportModule("traceback"); /* New reference. */
989 if (tb == NULL) {
990 cpy_log_exception("python initialization");
991 continue;
992 }
993 cpy_format_exception = PyObject_GetAttrString(tb, "format_exception"); /* New reference. */
994 Py_DECREF(tb);
995 if (cpy_format_exception == NULL)
996 cpy_log_exception("python initialization");
997 } else if (strcasecmp(item->key, "ModulePath") == 0) {
998 char *dir = NULL;
999 PyObject *dir_object;
1001 if (cf_util_get_string(item, &dir) != 0)
1002 continue;
1003 dir_object = cpy_string_to_unicode_or_bytes(dir); /* New reference. */
1004 if (dir_object == NULL) {
1005 ERROR("python plugin: Unable to convert \"%s\" to "
1006 "a python object.", dir);
1007 free(dir);
1008 cpy_log_exception("python initialization");
1009 continue;
1010 }
1011 if (PyList_Append(sys_path, dir_object) != 0) {
1012 ERROR("python plugin: Unable to append \"%s\" to "
1013 "python module path.", dir);
1014 cpy_log_exception("python initialization");
1015 }
1016 Py_DECREF(dir_object);
1017 free(dir);
1018 } else if (strcasecmp(item->key, "Import") == 0) {
1019 char *module_name = NULL;
1020 PyObject *module;
1022 if (cf_util_get_string(item, &module_name) != 0)
1023 continue;
1024 module = PyImport_ImportModule(module_name); /* New reference. */
1025 if (module == NULL) {
1026 ERROR("python plugin: Error importing module \"%s\".", module_name);
1027 cpy_log_exception("importing module");
1028 }
1029 free(module_name);
1030 Py_XDECREF(module);
1031 } else if (strcasecmp(item->key, "Module") == 0) {
1032 char *name = NULL;
1033 cpy_callback_t *c;
1034 PyObject *ret;
1036 if (cf_util_get_string(item, &name) != 0)
1037 continue;
1038 for (c = cpy_config_callbacks; c; c = c->next) {
1039 if (strcasecmp(c->name + 7, name) == 0)
1040 break;
1041 }
1042 if (c == NULL) {
1043 WARNING("python plugin: Found a configuration for the \"%s\" plugin, "
1044 "but the plugin isn't loaded or didn't register "
1045 "a configuration callback.", name);
1046 free(name);
1047 continue;
1048 }
1049 free(name);
1050 if (c->data == NULL)
1051 ret = PyObject_CallFunction(c->callback, "N",
1052 cpy_oconfig_to_pyconfig(item, NULL)); /* New reference. */
1053 else
1054 ret = PyObject_CallFunction(c->callback, "NO",
1055 cpy_oconfig_to_pyconfig(item, NULL), c->data); /* New reference. */
1056 if (ret == NULL)
1057 cpy_log_exception("loading module");
1058 else
1059 Py_DECREF(ret);
1060 } else {
1061 WARNING("python plugin: Ignoring unknown config key \"%s\".", item->key);
1062 }
1063 }
1064 Py_DECREF(sys_path);
1065 return 0;
1066 }
1068 void module_register(void) {
1069 plugin_register_complex_config("python", cpy_config);
1070 plugin_register_init("python", cpy_init);
1071 plugin_register_shutdown("python", cpy_shutdown);
1072 }