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 = PyString_AsString(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_GetAttrString(value, "message"); /* New reference. */
272 if (tn != NULL)
273 typename = PyString_AsString(tn);
274 if (m != NULL)
275 message = PyString_AsString(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 s = strdup(PyString_AsString(line));
305 if (s[strlen(s) - 1] == '\n')
306 s[strlen(s) - 1] = 0;
307 Py_BEGIN_ALLOW_THREADS
308 ERROR("%s", s);
309 Py_END_ALLOW_THREADS
310 free(s);
311 }
312 Py_XDECREF(list);
313 PyErr_Clear();
314 }
316 static int cpy_read_callback(user_data_t *data) {
317 cpy_callback_t *c = data->data;
318 PyObject *ret;
320 CPY_LOCK_THREADS
321 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
322 if (ret == NULL) {
323 cpy_log_exception("read callback");
324 } else {
325 Py_DECREF(ret);
326 }
327 CPY_RELEASE_THREADS
328 if (ret == NULL)
329 return 1;
330 return 0;
331 }
333 static int cpy_write_callback(const data_set_t *ds, const value_list_t *value_list, user_data_t *data) {
334 int i;
335 cpy_callback_t *c = data->data;
336 PyObject *ret, *v, *list;
338 CPY_LOCK_THREADS
339 list = PyList_New(value_list->values_len); /* New reference. */
340 if (list == NULL) {
341 cpy_log_exception("write callback");
342 CPY_RETURN_FROM_THREADS 0;
343 }
344 for (i = 0; i < value_list->values_len; ++i) {
345 if (ds->ds->type == DS_TYPE_COUNTER) {
346 if ((long) value_list->values[i].counter == value_list->values[i].counter)
347 PyList_SetItem(list, i, PyInt_FromLong(value_list->values[i].counter));
348 else
349 PyList_SetItem(list, i, PyLong_FromUnsignedLongLong(value_list->values[i].counter));
350 } else if (ds->ds->type == DS_TYPE_GAUGE) {
351 PyList_SetItem(list, i, PyFloat_FromDouble(value_list->values[i].gauge));
352 } else if (ds->ds->type == DS_TYPE_DERIVE) {
353 if ((long) value_list->values[i].derive == value_list->values[i].derive)
354 PyList_SetItem(list, i, PyInt_FromLong(value_list->values[i].derive));
355 else
356 PyList_SetItem(list, i, PyLong_FromLongLong(value_list->values[i].derive));
357 } else if (ds->ds->type == DS_TYPE_ABSOLUTE) {
358 if ((long) value_list->values[i].absolute == value_list->values[i].absolute)
359 PyList_SetItem(list, i, PyInt_FromLong(value_list->values[i].absolute));
360 else
361 PyList_SetItem(list, i, PyLong_FromUnsignedLongLong(value_list->values[i].absolute));
362 } else {
363 Py_BEGIN_ALLOW_THREADS
364 ERROR("cpy_write_callback: Unknown value type %d.", ds->ds->type);
365 Py_END_ALLOW_THREADS
366 Py_DECREF(list);
367 CPY_RETURN_FROM_THREADS 0;
368 }
369 if (PyErr_Occurred() != NULL) {
370 cpy_log_exception("value building for write callback");
371 CPY_RETURN_FROM_THREADS 0;
372 }
373 }
374 v = PyObject_CallFunction((void *) &ValuesType, "sOssssdi", value_list->type, list,
375 value_list->plugin_instance, value_list->type_instance, value_list->plugin,
376 value_list->host, (double) value_list->time, value_list->interval);
377 Py_DECREF(list);
378 ret = PyObject_CallFunctionObjArgs(c->callback, v, c->data, (void *) 0); /* New reference. */
379 if (ret == NULL) {
380 cpy_log_exception("write callback");
381 } else {
382 Py_DECREF(ret);
383 }
384 CPY_RELEASE_THREADS
385 return 0;
386 }
388 static int cpy_notification_callback(const notification_t *notification, user_data_t *data) {
389 cpy_callback_t *c = data->data;
390 PyObject *ret, *n;
392 CPY_LOCK_THREADS
393 n = PyObject_CallFunction((void *) &NotificationType, "ssssssdi", notification->type, notification->message,
394 notification->plugin_instance, notification->type_instance, notification->plugin,
395 notification->host, (double) notification->time, notification->severity);
396 ret = PyObject_CallFunctionObjArgs(c->callback, n, c->data, (void *) 0); /* New reference. */
397 if (ret == NULL) {
398 cpy_log_exception("notification callback");
399 } else {
400 Py_DECREF(ret);
401 }
402 CPY_RELEASE_THREADS
403 return 0;
404 }
406 static void cpy_log_callback(int severity, const char *message, user_data_t *data) {
407 cpy_callback_t * c = data->data;
408 PyObject *ret;
410 CPY_LOCK_THREADS
411 if (c->data == NULL)
412 ret = PyObject_CallFunction(c->callback, "is", severity, message); /* New reference. */
413 else
414 ret = PyObject_CallFunction(c->callback, "isO", severity, message, c->data); /* New reference. */
416 if (ret == NULL) {
417 /* FIXME */
418 /* Do we really want to trigger a log callback because a log callback failed?
419 * Probably not. */
420 PyErr_Print();
421 /* In case someone wanted to be clever, replaced stderr and failed at that. */
422 PyErr_Clear();
423 } else {
424 Py_DECREF(ret);
425 }
426 CPY_RELEASE_THREADS
427 }
429 static void cpy_flush_callback(int timeout, const char *id, user_data_t *data) {
430 cpy_callback_t * c = data->data;
431 PyObject *ret;
433 CPY_LOCK_THREADS
434 if (c->data == NULL)
435 ret = PyObject_CallFunction(c->callback, "is", timeout, id); /* New reference. */
436 else
437 ret = PyObject_CallFunction(c->callback, "isO", timeout, id, c->data); /* New reference. */
439 if (ret == NULL) {
440 cpy_log_exception("flush callback");
441 } else {
442 Py_DECREF(ret);
443 }
444 CPY_RELEASE_THREADS
445 }
447 static PyObject *cpy_register_generic(cpy_callback_t **list_head, PyObject *args, PyObject *kwds) {
448 char buf[512];
449 cpy_callback_t *c;
450 const char *name = NULL;
451 PyObject *callback = NULL, *data = NULL, *mod = NULL;
452 static char *kwlist[] = {"callback", "data", "name", NULL};
454 if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oz", kwlist, &callback, &data, &name) == 0) return NULL;
455 if (PyCallable_Check(callback) == 0) {
456 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
457 return NULL;
458 }
459 cpy_build_name(buf, sizeof(buf), callback, name);
461 Py_INCREF(callback);
462 Py_XINCREF(data);
463 c = malloc(sizeof(*c));
464 c->name = strdup(buf);
465 c->callback = callback;
466 c->data = data;
467 c->next = *list_head;
468 *list_head = c;
469 Py_XDECREF(mod);
470 return PyString_FromString(buf);
471 }
473 static PyObject *cpy_flush(cpy_callback_t **list_head, PyObject *args, PyObject *kwds) {
474 int timeout = -1;
475 const char *plugin = NULL, *identifier = NULL;
476 static char *kwlist[] = {"plugin", "timeout", "identifier", NULL};
478 if (PyArg_ParseTupleAndKeywords(args, kwds, "|ziz", kwlist, &plugin, &timeout, &identifier) == 0) return NULL;
479 Py_BEGIN_ALLOW_THREADS
480 plugin_flush(plugin, timeout, identifier);
481 Py_END_ALLOW_THREADS
482 Py_RETURN_NONE;
483 }
485 static PyObject *cpy_register_config(PyObject *self, PyObject *args, PyObject *kwds) {
486 return cpy_register_generic(&cpy_config_callbacks, args, kwds);
487 }
489 static PyObject *cpy_register_init(PyObject *self, PyObject *args, PyObject *kwds) {
490 return cpy_register_generic(&cpy_init_callbacks, args, kwds);
491 }
493 typedef int reg_function_t(const char *name, void *callback, void *data);
495 static PyObject *cpy_register_generic_userdata(void *reg, void *handler, PyObject *args, PyObject *kwds) {
496 char buf[512];
497 reg_function_t *register_function = (reg_function_t *) reg;
498 cpy_callback_t *c = NULL;
499 user_data_t *user_data = NULL;
500 const char *name = NULL;
501 PyObject *callback = NULL, *data = NULL;
502 static char *kwlist[] = {"callback", "data", "name", NULL};
504 if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oz", kwlist, &callback, &data, &name) == 0) return NULL;
505 if (PyCallable_Check(callback) == 0) {
506 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
507 return NULL;
508 }
509 cpy_build_name(buf, sizeof(buf), callback, name);
511 Py_INCREF(callback);
512 Py_XINCREF(data);
513 c = malloc(sizeof(*c));
514 c->name = strdup(buf);
515 c->callback = callback;
516 c->data = data;
517 c->next = NULL;
518 user_data = malloc(sizeof(*user_data));
519 user_data->free_func = cpy_destroy_user_data;
520 user_data->data = c;
521 register_function(buf, handler, user_data);
522 return PyString_FromString(buf);
523 }
525 static PyObject *cpy_register_read(PyObject *self, PyObject *args, PyObject *kwds) {
526 char buf[512];
527 cpy_callback_t *c = NULL;
528 user_data_t *user_data = NULL;
529 double interval = 0;
530 const char *name = NULL;
531 PyObject *callback = NULL, *data = NULL;
532 struct timespec ts;
533 static char *kwlist[] = {"callback", "interval", "data", "name", NULL};
535 if (PyArg_ParseTupleAndKeywords(args, kwds, "O|dOz", kwlist, &callback, &interval, &data, &name) == 0) return NULL;
536 if (PyCallable_Check(callback) == 0) {
537 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
538 return NULL;
539 }
540 cpy_build_name(buf, sizeof(buf), callback, name);
542 Py_INCREF(callback);
543 Py_XINCREF(data);
544 c = malloc(sizeof(*c));
545 c->name = strdup(buf);
546 c->callback = callback;
547 c->data = data;
548 c->next = NULL;
549 user_data = malloc(sizeof(*user_data));
550 user_data->free_func = cpy_destroy_user_data;
551 user_data->data = c;
552 ts.tv_sec = interval;
553 ts.tv_nsec = (interval - ts.tv_sec) * 1000000000;
554 plugin_register_complex_read(buf, cpy_read_callback, &ts, user_data);
555 return PyString_FromString(buf);
556 }
558 static PyObject *cpy_register_log(PyObject *self, PyObject *args, PyObject *kwds) {
559 return cpy_register_generic_userdata((void *) plugin_register_log,
560 (void *) cpy_log_callback, args, kwds);
561 }
563 static PyObject *cpy_register_write(PyObject *self, PyObject *args, PyObject *kwds) {
564 return cpy_register_generic_userdata((void *) plugin_register_write,
565 (void *) cpy_write_callback, args, kwds);
566 }
568 static PyObject *cpy_register_notification(PyObject *self, PyObject *args, PyObject *kwds) {
569 return cpy_register_generic_userdata((void *) plugin_register_notification,
570 (void *) cpy_notification_callback, args, kwds);
571 }
573 static PyObject *cpy_register_flush(PyObject *self, PyObject *args, PyObject *kwds) {
574 return cpy_register_generic_userdata((void *) plugin_register_flush,
575 (void *) cpy_flush_callback, args, kwds);
576 }
578 static PyObject *cpy_register_shutdown(PyObject *self, PyObject *args, PyObject *kwds) {
579 return cpy_register_generic(&cpy_shutdown_callbacks, args, kwds);
580 }
582 static PyObject *cpy_error(PyObject *self, PyObject *args) {
583 const char *text;
584 if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
585 Py_BEGIN_ALLOW_THREADS
586 plugin_log(LOG_ERR, "%s", text);
587 Py_END_ALLOW_THREADS
588 Py_RETURN_NONE;
589 }
591 static PyObject *cpy_warning(PyObject *self, PyObject *args) {
592 const char *text;
593 if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
594 Py_BEGIN_ALLOW_THREADS
595 plugin_log(LOG_WARNING, "%s", text);
596 Py_END_ALLOW_THREADS
597 Py_RETURN_NONE;
598 }
600 static PyObject *cpy_notice(PyObject *self, PyObject *args) {
601 const char *text;
602 if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
603 Py_BEGIN_ALLOW_THREADS
604 plugin_log(LOG_NOTICE, "%s", text);
605 Py_END_ALLOW_THREADS
606 Py_RETURN_NONE;
607 }
609 static PyObject *cpy_info(PyObject *self, PyObject *args) {
610 const char *text;
611 if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
612 Py_BEGIN_ALLOW_THREADS
613 plugin_log(LOG_INFO, "%s", text);
614 Py_END_ALLOW_THREADS
615 Py_RETURN_NONE;
616 }
618 static PyObject *cpy_debug(PyObject *self, PyObject *args) {
619 #ifdef COLLECT_DEBUG
620 const char *text;
621 if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
622 Py_BEGIN_ALLOW_THREADS
623 plugin_log(LOG_DEBUG, "%s", text);
624 Py_END_ALLOW_THREADS
625 #endif
626 Py_RETURN_NONE;
627 }
629 static PyObject *cpy_unregister_generic(cpy_callback_t **list_head, PyObject *arg, const char *desc) {
630 char buf[512];
631 const char *name;
632 cpy_callback_t *prev = NULL, *tmp;
634 if (PyUnicode_Check(arg)) {
635 arg = PyUnicode_AsEncodedString(arg, NULL, NULL);
636 if (arg == NULL)
637 return NULL;
638 name = PyString_AsString(arg);
639 Py_DECREF(arg);
640 } else if (PyString_Check(arg)) {
641 name = PyString_AsString(arg);
642 } else {
643 if (!PyCallable_Check(arg)) {
644 PyErr_SetString(PyExc_TypeError, "This function needs a string or a callable object as its only parameter.");
645 return NULL;
646 }
647 cpy_build_name(buf, sizeof(buf), arg, NULL);
648 name = buf;
649 }
650 for (tmp = *list_head; tmp; prev = tmp, tmp = tmp->next)
651 if (strcmp(name, tmp->name) == 0)
652 break;
654 if (tmp == NULL) {
655 PyErr_Format(PyExc_RuntimeError, "Unable to unregister %s callback '%s'.", desc, name);
656 return NULL;
657 }
658 /* Yes, this is actually save. To call this function the caller has to
659 * hold the GIL. Well, save as long as there is only one GIL anyway ... */
660 if (prev == NULL)
661 *list_head = tmp->next;
662 else
663 prev->next = tmp->next;
664 cpy_destroy_user_data(tmp);
665 Py_RETURN_NONE;
666 }
668 typedef int cpy_unregister_function_t(const char *name);
670 static PyObject *cpy_unregister_generic_userdata(cpy_unregister_function_t *unreg, PyObject *arg, const char *desc) {
671 char buf[512];
672 const char *name;
674 if (PyUnicode_Check(arg)) {
675 arg = PyUnicode_AsEncodedString(arg, NULL, NULL);
676 if (arg == NULL)
677 return NULL;
678 name = PyString_AsString(arg);
679 Py_DECREF(arg);
680 } else if (PyString_Check(arg)) {
681 name = PyString_AsString(arg);
682 } else {
683 if (!PyCallable_Check(arg)) {
684 PyErr_SetString(PyExc_TypeError, "This function needs a string or a callable object as its only parameter.");
685 return NULL;
686 }
687 cpy_build_name(buf, sizeof(buf), arg, NULL);
688 name = buf;
689 }
690 if (unreg(name) == 0)
691 Py_RETURN_NONE;
692 PyErr_Format(PyExc_RuntimeError, "Unable to unregister %s callback '%s'.", desc, name);
693 return NULL;
694 }
696 static PyObject *cpy_unregister_log(PyObject *self, PyObject *arg) {
697 return cpy_unregister_generic_userdata(plugin_unregister_log, arg, "log");
698 }
700 static PyObject *cpy_unregister_init(PyObject *self, PyObject *arg) {
701 return cpy_unregister_generic(&cpy_init_callbacks, arg, "init");
702 }
704 static PyObject *cpy_unregister_config(PyObject *self, PyObject *arg) {
705 return cpy_unregister_generic(&cpy_config_callbacks, arg, "config");
706 }
708 static PyObject *cpy_unregister_read(PyObject *self, PyObject *arg) {
709 return cpy_unregister_generic_userdata(plugin_unregister_read, arg, "read");
710 }
712 static PyObject *cpy_unregister_write(PyObject *self, PyObject *arg) {
713 return cpy_unregister_generic_userdata(plugin_unregister_write, arg, "write");
714 }
716 static PyObject *cpy_unregister_notification(PyObject *self, PyObject *arg) {
717 return cpy_unregister_generic_userdata(plugin_unregister_notification, arg, "notification");
718 }
720 static PyObject *cpy_unregister_flush(PyObject *self, PyObject *arg) {
721 return cpy_unregister_generic_userdata(plugin_unregister_flush, arg, "flush");
722 }
724 static PyObject *cpy_unregister_shutdown(PyObject *self, PyObject *arg) {
725 return cpy_unregister_generic(&cpy_shutdown_callbacks, arg, "shutdown");
726 }
728 static PyMethodDef cpy_methods[] = {
729 {"debug", cpy_debug, METH_VARARGS, log_doc},
730 {"info", cpy_info, METH_VARARGS, log_doc},
731 {"notice", cpy_notice, METH_VARARGS, log_doc},
732 {"warning", cpy_warning, METH_VARARGS, log_doc},
733 {"error", cpy_error, METH_VARARGS, log_doc},
734 {"flush", (PyCFunction) cpy_flush, METH_VARARGS | METH_KEYWORDS, flush_doc},
735 {"register_log", (PyCFunction) cpy_register_log, METH_VARARGS | METH_KEYWORDS, reg_log_doc},
736 {"register_init", (PyCFunction) cpy_register_init, METH_VARARGS | METH_KEYWORDS, reg_init_doc},
737 {"register_config", (PyCFunction) cpy_register_config, METH_VARARGS | METH_KEYWORDS, reg_config_doc},
738 {"register_read", (PyCFunction) cpy_register_read, METH_VARARGS | METH_KEYWORDS, reg_read_doc},
739 {"register_write", (PyCFunction) cpy_register_write, METH_VARARGS | METH_KEYWORDS, reg_write_doc},
740 {"register_notification", (PyCFunction) cpy_register_notification, METH_VARARGS | METH_KEYWORDS, reg_notification_doc},
741 {"register_flush", (PyCFunction) cpy_register_flush, METH_VARARGS | METH_KEYWORDS, reg_flush_doc},
742 {"register_shutdown", (PyCFunction) cpy_register_shutdown, METH_VARARGS | METH_KEYWORDS, reg_shutdown_doc},
743 {"unregister_log", cpy_unregister_log, METH_O, unregister_doc},
744 {"unregister_init", cpy_unregister_init, METH_O, unregister_doc},
745 {"unregister_config", cpy_unregister_config, METH_O, unregister_doc},
746 {"unregister_read", cpy_unregister_read, METH_O, unregister_doc},
747 {"unregister_write", cpy_unregister_write, METH_O, unregister_doc},
748 {"unregister_notification", cpy_unregister_notification, METH_O, unregister_doc},
749 {"unregister_flush", cpy_unregister_flush, METH_O, unregister_doc},
750 {"unregister_shutdown", cpy_unregister_shutdown, METH_O, unregister_doc},
751 {0, 0, 0, 0}
752 };
754 static int cpy_shutdown(void) {
755 cpy_callback_t *c;
756 PyObject *ret;
758 /* This can happen if the module was loaded but not configured. */
759 if (state != NULL)
760 PyEval_RestoreThread(state);
762 for (c = cpy_shutdown_callbacks; c; c = c->next) {
763 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
764 if (ret == NULL)
765 cpy_log_exception("shutdown callback");
766 else
767 Py_DECREF(ret);
768 }
769 PyErr_Print();
770 Py_Finalize();
771 return 0;
772 }
774 static void cpy_int_handler(int sig) {
775 return;
776 }
778 static void *cpy_interactive(void *data) {
779 sigset_t sigset;
780 struct sigaction sig_int_action, old;
782 /* Signal handler in a plugin? Bad stuff, but the best way to
783 * handle it I guess. In an interactive session people will
784 * press Ctrl+C at some time, which will generate a SIGINT.
785 * This will cause collectd to shutdown, thus killing the
786 * interactive interpreter, and leaving the terminal in a
787 * mess. Chances are, this isn't what the user wanted to do.
788 *
789 * So this is the plan:
790 * 1. Block SIGINT in the main thread.
791 * 2. Install our own signal handler that does nothing.
792 * 3. Unblock SIGINT in the interactive thread.
793 *
794 * This will make sure that SIGINT won't kill collectd but
795 * still interrupt syscalls like sleep and pause.
796 * It does not raise a KeyboardInterrupt exception because so
797 * far nobody managed to figure out how to do that. */
798 memset (&sig_int_action, '\0', sizeof (sig_int_action));
799 sig_int_action.sa_handler = cpy_int_handler;
800 sigaction (SIGINT, &sig_int_action, &old);
802 sigemptyset(&sigset);
803 sigaddset(&sigset, SIGINT);
804 pthread_sigmask(SIG_UNBLOCK, &sigset, NULL);
805 PyEval_AcquireThread(state);
806 if (PyImport_ImportModule("readline") == NULL) {
807 /* This interactive session will suck. */
808 cpy_log_exception("interactive session init");
809 }
810 PyRun_InteractiveLoop(stdin, "<stdin>");
811 PyErr_Print();
812 PyEval_ReleaseThread(state);
813 NOTICE("python: Interactive interpreter exited, stopping collectd ...");
814 /* Restore the original collectd SIGINT handler and raise SIGINT.
815 * The main thread still has SIGINT blocked and there's nothing we
816 * can do about that so this thread will handle it. But that's not
817 * important, except that it won't interrupt the main loop and so
818 * it might take a few seconds before collectd really shuts down. */
819 sigaction (SIGINT, &old, NULL);
820 raise(SIGINT);
821 pause();
822 return NULL;
823 }
825 static int cpy_init(void) {
826 cpy_callback_t *c;
827 PyObject *ret;
828 static pthread_t thread;
829 sigset_t sigset;
831 PyEval_InitThreads();
832 /* Now it's finally OK to use python threads. */
833 for (c = cpy_init_callbacks; c; c = c->next) {
834 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
835 if (ret == NULL)
836 cpy_log_exception("init callback");
837 else
838 Py_DECREF(ret);
839 }
840 sigemptyset(&sigset);
841 sigaddset(&sigset, SIGINT);
842 pthread_sigmask(SIG_BLOCK, &sigset, NULL);
843 state = PyEval_SaveThread();
844 if (do_interactive) {
845 if (pthread_create(&thread, NULL, cpy_interactive, NULL)) {
846 ERROR("python: Error creating thread for interactive interpreter.");
847 }
848 }
850 return 0;
851 }
853 static PyObject *cpy_oconfig_to_pyconfig(oconfig_item_t *ci, PyObject *parent) {
854 int i;
855 PyObject *item, *values, *children, *tmp;
857 if (parent == NULL)
858 parent = Py_None;
860 values = PyTuple_New(ci->values_num); /* New reference. */
861 for (i = 0; i < ci->values_num; ++i) {
862 if (ci->values[i].type == OCONFIG_TYPE_STRING) {
863 PyTuple_SET_ITEM(values, i, PyString_FromString(ci->values[i].value.string));
864 } else if (ci->values[i].type == OCONFIG_TYPE_NUMBER) {
865 PyTuple_SET_ITEM(values, i, PyFloat_FromDouble(ci->values[i].value.number));
866 } else if (ci->values[i].type == OCONFIG_TYPE_BOOLEAN) {
867 PyTuple_SET_ITEM(values, i, PyBool_FromLong(ci->values[i].value.boolean));
868 }
869 }
871 item = PyObject_CallFunction((void *) &ConfigType, "sONO", ci->key, parent, values, Py_None);
872 if (item == NULL)
873 return NULL;
874 children = PyTuple_New(ci->children_num); /* New reference. */
875 for (i = 0; i < ci->children_num; ++i) {
876 PyTuple_SET_ITEM(children, i, cpy_oconfig_to_pyconfig(ci->children + i, item));
877 }
878 tmp = ((Config *) item)->children;
879 ((Config *) item)->children = children;
880 Py_XDECREF(tmp);
881 return item;
882 }
884 static int cpy_config(oconfig_item_t *ci) {
885 int i;
886 PyObject *sys, *tb;
887 PyObject *sys_path;
888 PyObject *module;
890 /* Ok in theory we shouldn't do initialization at this point
891 * but we have to. In order to give python scripts a chance
892 * to register a config callback we need to be able to execute
893 * python code during the config callback so we have to start
894 * the interpreter here. */
895 /* Do *not* use the python "thread" module at this point! */
896 Py_Initialize();
898 PyType_Ready(&ConfigType);
899 PyType_Ready(&PluginDataType);
900 ValuesType.tp_base = &PluginDataType;
901 PyType_Ready(&ValuesType);
902 NotificationType.tp_base = &PluginDataType;
903 PyType_Ready(&NotificationType);
904 sys = PyImport_ImportModule("sys"); /* New reference. */
905 if (sys == NULL) {
906 cpy_log_exception("python initialization");
907 return 1;
908 }
909 sys_path = PyObject_GetAttrString(sys, "path"); /* New reference. */
910 Py_DECREF(sys);
911 if (sys_path == NULL) {
912 cpy_log_exception("python initialization");
913 return 1;
914 }
915 module = Py_InitModule("collectd", cpy_methods); /* Borrowed reference. */
916 PyModule_AddObject(module, "Config", (void *) &ConfigType); /* Steals a reference. */
917 PyModule_AddObject(module, "Values", (void *) &ValuesType); /* Steals a reference. */
918 PyModule_AddObject(module, "Notification", (void *) &NotificationType); /* Steals a reference. */
919 PyModule_AddIntConstant(module, "LOG_DEBUG", LOG_DEBUG);
920 PyModule_AddIntConstant(module, "LOG_INFO", LOG_INFO);
921 PyModule_AddIntConstant(module, "LOG_NOTICE", LOG_NOTICE);
922 PyModule_AddIntConstant(module, "LOG_WARNING", LOG_WARNING);
923 PyModule_AddIntConstant(module, "LOG_ERROR", LOG_ERR);
924 PyModule_AddIntConstant(module, "NOTIF_FAILURE", NOTIF_FAILURE);
925 PyModule_AddIntConstant(module, "NOTIF_WARNING", NOTIF_WARNING);
926 PyModule_AddIntConstant(module, "NOTIF_OKAY", NOTIF_OKAY);
927 for (i = 0; i < ci->children_num; ++i) {
928 oconfig_item_t *item = ci->children + i;
930 if (strcasecmp(item->key, "Interactive") == 0) {
931 if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_BOOLEAN)
932 continue;
933 do_interactive = item->values[0].value.boolean;
934 } else if (strcasecmp(item->key, "Encoding") == 0) {
935 if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_STRING)
936 continue;
937 /* Why is this even necessary? And undocumented? */
938 if (PyUnicode_SetDefaultEncoding(item->values[0].value.string))
939 cpy_log_exception("setting default encoding");
940 } else if (strcasecmp(item->key, "LogTraces") == 0) {
941 if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_BOOLEAN)
942 continue;
943 if (!item->values[0].value.boolean) {
944 Py_XDECREF(cpy_format_exception);
945 cpy_format_exception = NULL;
946 continue;
947 }
948 if (cpy_format_exception)
949 continue;
950 tb = PyImport_ImportModule("traceback"); /* New reference. */
951 if (tb == NULL) {
952 cpy_log_exception("python initialization");
953 continue;
954 }
955 cpy_format_exception = PyObject_GetAttrString(tb, "format_exception"); /* New reference. */
956 Py_DECREF(tb);
957 if (cpy_format_exception == NULL)
958 cpy_log_exception("python initialization");
959 } else if (strcasecmp(item->key, "ModulePath") == 0) {
960 char *dir = NULL;
961 PyObject *dir_object;
963 if (cf_util_get_string(item, &dir) != 0)
964 continue;
965 dir_object = PyString_FromString(dir); /* New reference. */
966 if (dir_object == NULL) {
967 ERROR("python plugin: Unable to convert \"%s\" to "
968 "a python object.", dir);
969 free(dir);
970 cpy_log_exception("python initialization");
971 continue;
972 }
973 if (PyList_Append(sys_path, dir_object) != 0) {
974 ERROR("python plugin: Unable to append \"%s\" to "
975 "python module path.", dir);
976 cpy_log_exception("python initialization");
977 }
978 Py_DECREF(dir_object);
979 free(dir);
980 } else if (strcasecmp(item->key, "Import") == 0) {
981 char *module_name = NULL;
982 PyObject *module;
984 if (cf_util_get_string(item, &module_name) != 0)
985 continue;
986 module = PyImport_ImportModule(module_name); /* New reference. */
987 if (module == NULL) {
988 ERROR("python plugin: Error importing module \"%s\".", module_name);
989 cpy_log_exception("importing module");
990 PyErr_Print();
991 }
992 free(module_name);
993 Py_XDECREF(module);
994 } else if (strcasecmp(item->key, "Module") == 0) {
995 char *name = NULL;
996 cpy_callback_t *c;
997 PyObject *ret;
999 if (cf_util_get_string(item, &name) != 0)
1000 continue;
1001 for (c = cpy_config_callbacks; c; c = c->next) {
1002 if (strcasecmp(c->name + 7, name) == 0)
1003 break;
1004 }
1005 if (c == NULL) {
1006 WARNING("python plugin: Found a configuration for the \"%s\" plugin, "
1007 "but the plugin isn't loaded or didn't register "
1008 "a configuration callback.", name);
1009 free(name);
1010 continue;
1011 }
1012 free(name);
1013 if (c->data == NULL)
1014 ret = PyObject_CallFunction(c->callback, "N",
1015 cpy_oconfig_to_pyconfig(item, NULL)); /* New reference. */
1016 else
1017 ret = PyObject_CallFunction(c->callback, "NO",
1018 cpy_oconfig_to_pyconfig(item, NULL), c->data); /* New reference. */
1019 if (ret == NULL)
1020 cpy_log_exception("loading module");
1021 else
1022 Py_DECREF(ret);
1023 } else {
1024 WARNING("python plugin: Ignoring unknown config key \"%s\".", item->key);
1025 }
1026 }
1027 Py_DECREF(sys_path);
1028 return 0;
1029 }
1031 void module_register(void) {
1032 plugin_register_complex_config("python", cpy_config);
1033 plugin_register_init("python", cpy_init);
1034 plugin_register_shutdown("python", cpy_shutdown);
1035 }