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 Py_DECREF(line);
306 if (s[strlen(s) - 1] == '\n')
307 s[strlen(s) - 1] = 0;
308 Py_BEGIN_ALLOW_THREADS
309 ERROR("%s", s);
310 Py_END_ALLOW_THREADS
311 free(s);
312 }
313 Py_XDECREF(list);
314 PyErr_Clear();
315 }
317 static int cpy_read_callback(user_data_t *data) {
318 cpy_callback_t *c = data->data;
319 PyObject *ret;
321 CPY_LOCK_THREADS
322 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
323 if (ret == NULL) {
324 cpy_log_exception("read callback");
325 } else {
326 Py_DECREF(ret);
327 }
328 CPY_RELEASE_THREADS
329 if (ret == NULL)
330 return 1;
331 return 0;
332 }
334 static int cpy_write_callback(const data_set_t *ds, const value_list_t *value_list, user_data_t *data) {
335 int i;
336 cpy_callback_t *c = data->data;
337 PyObject *ret, *v, *list;
339 CPY_LOCK_THREADS
340 list = PyList_New(value_list->values_len); /* New reference. */
341 if (list == NULL) {
342 cpy_log_exception("write callback");
343 CPY_RETURN_FROM_THREADS 0;
344 }
345 for (i = 0; i < value_list->values_len; ++i) {
346 if (ds->ds->type == DS_TYPE_COUNTER) {
347 if ((long) value_list->values[i].counter == value_list->values[i].counter)
348 PyList_SetItem(list, i, PyInt_FromLong(value_list->values[i].counter));
349 else
350 PyList_SetItem(list, i, PyLong_FromUnsignedLongLong(value_list->values[i].counter));
351 } else if (ds->ds->type == DS_TYPE_GAUGE) {
352 PyList_SetItem(list, i, PyFloat_FromDouble(value_list->values[i].gauge));
353 } else if (ds->ds->type == DS_TYPE_DERIVE) {
354 if ((long) value_list->values[i].derive == value_list->values[i].derive)
355 PyList_SetItem(list, i, PyInt_FromLong(value_list->values[i].derive));
356 else
357 PyList_SetItem(list, i, PyLong_FromLongLong(value_list->values[i].derive));
358 } else if (ds->ds->type == DS_TYPE_ABSOLUTE) {
359 if ((long) value_list->values[i].absolute == value_list->values[i].absolute)
360 PyList_SetItem(list, i, PyInt_FromLong(value_list->values[i].absolute));
361 else
362 PyList_SetItem(list, i, PyLong_FromUnsignedLongLong(value_list->values[i].absolute));
363 } else {
364 Py_BEGIN_ALLOW_THREADS
365 ERROR("cpy_write_callback: Unknown value type %d.", ds->ds->type);
366 Py_END_ALLOW_THREADS
367 Py_DECREF(list);
368 CPY_RETURN_FROM_THREADS 0;
369 }
370 if (PyErr_Occurred() != NULL) {
371 cpy_log_exception("value building for write callback");
372 CPY_RETURN_FROM_THREADS 0;
373 }
374 }
375 v = PyObject_CallFunction((void *) &ValuesType, "sOssssdi", value_list->type, list,
376 value_list->plugin_instance, value_list->type_instance, value_list->plugin,
377 value_list->host, (double) value_list->time, value_list->interval);
378 Py_DECREF(list);
379 ret = PyObject_CallFunctionObjArgs(c->callback, v, c->data, (void *) 0); /* New reference. */
380 if (ret == NULL) {
381 cpy_log_exception("write callback");
382 } else {
383 Py_DECREF(ret);
384 }
385 CPY_RELEASE_THREADS
386 return 0;
387 }
389 static int cpy_notification_callback(const notification_t *notification, user_data_t *data) {
390 cpy_callback_t *c = data->data;
391 PyObject *ret, *n;
393 CPY_LOCK_THREADS
394 n = PyObject_CallFunction((void *) &NotificationType, "ssssssdi", notification->type, notification->message,
395 notification->plugin_instance, notification->type_instance, notification->plugin,
396 notification->host, (double) notification->time, notification->severity);
397 ret = PyObject_CallFunctionObjArgs(c->callback, n, c->data, (void *) 0); /* New reference. */
398 if (ret == NULL) {
399 cpy_log_exception("notification callback");
400 } else {
401 Py_DECREF(ret);
402 }
403 CPY_RELEASE_THREADS
404 return 0;
405 }
407 static void cpy_log_callback(int severity, const char *message, user_data_t *data) {
408 cpy_callback_t * c = data->data;
409 PyObject *ret;
411 CPY_LOCK_THREADS
412 if (c->data == NULL)
413 ret = PyObject_CallFunction(c->callback, "is", severity, message); /* New reference. */
414 else
415 ret = PyObject_CallFunction(c->callback, "isO", severity, message, c->data); /* New reference. */
417 if (ret == NULL) {
418 /* FIXME */
419 /* Do we really want to trigger a log callback because a log callback failed?
420 * Probably not. */
421 PyErr_Print();
422 /* In case someone wanted to be clever, replaced stderr and failed at that. */
423 PyErr_Clear();
424 } else {
425 Py_DECREF(ret);
426 }
427 CPY_RELEASE_THREADS
428 }
430 static void cpy_flush_callback(int timeout, const char *id, user_data_t *data) {
431 cpy_callback_t * c = data->data;
432 PyObject *ret;
434 CPY_LOCK_THREADS
435 if (c->data == NULL)
436 ret = PyObject_CallFunction(c->callback, "is", timeout, id); /* New reference. */
437 else
438 ret = PyObject_CallFunction(c->callback, "isO", timeout, id, c->data); /* New reference. */
440 if (ret == NULL) {
441 cpy_log_exception("flush callback");
442 } else {
443 Py_DECREF(ret);
444 }
445 CPY_RELEASE_THREADS
446 }
448 static PyObject *cpy_register_generic(cpy_callback_t **list_head, PyObject *args, PyObject *kwds) {
449 char buf[512];
450 cpy_callback_t *c;
451 const char *name = NULL;
452 PyObject *callback = NULL, *data = NULL, *mod = NULL;
453 static char *kwlist[] = {"callback", "data", "name", NULL};
455 if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oz", kwlist, &callback, &data, &name) == 0) return NULL;
456 if (PyCallable_Check(callback) == 0) {
457 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
458 return NULL;
459 }
460 cpy_build_name(buf, sizeof(buf), callback, name);
462 Py_INCREF(callback);
463 Py_XINCREF(data);
464 c = malloc(sizeof(*c));
465 c->name = strdup(buf);
466 c->callback = callback;
467 c->data = data;
468 c->next = *list_head;
469 *list_head = c;
470 Py_XDECREF(mod);
471 return PyString_FromString(buf);
472 }
474 static PyObject *cpy_flush(cpy_callback_t **list_head, PyObject *args, PyObject *kwds) {
475 int timeout = -1;
476 const char *plugin = NULL, *identifier = NULL;
477 static char *kwlist[] = {"plugin", "timeout", "identifier", NULL};
479 if (PyArg_ParseTupleAndKeywords(args, kwds, "|ziz", kwlist, &plugin, &timeout, &identifier) == 0) return NULL;
480 Py_BEGIN_ALLOW_THREADS
481 plugin_flush(plugin, timeout, identifier);
482 Py_END_ALLOW_THREADS
483 Py_RETURN_NONE;
484 }
486 static PyObject *cpy_register_config(PyObject *self, PyObject *args, PyObject *kwds) {
487 return cpy_register_generic(&cpy_config_callbacks, args, kwds);
488 }
490 static PyObject *cpy_register_init(PyObject *self, PyObject *args, PyObject *kwds) {
491 return cpy_register_generic(&cpy_init_callbacks, args, kwds);
492 }
494 typedef int reg_function_t(const char *name, void *callback, void *data);
496 static PyObject *cpy_register_generic_userdata(void *reg, void *handler, PyObject *args, PyObject *kwds) {
497 char buf[512];
498 reg_function_t *register_function = (reg_function_t *) reg;
499 cpy_callback_t *c = NULL;
500 user_data_t *user_data = NULL;
501 const char *name = NULL;
502 PyObject *callback = NULL, *data = NULL;
503 static char *kwlist[] = {"callback", "data", "name", NULL};
505 if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oz", kwlist, &callback, &data, &name) == 0) return NULL;
506 if (PyCallable_Check(callback) == 0) {
507 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
508 return NULL;
509 }
510 cpy_build_name(buf, sizeof(buf), callback, name);
512 Py_INCREF(callback);
513 Py_XINCREF(data);
514 c = malloc(sizeof(*c));
515 c->name = strdup(buf);
516 c->callback = callback;
517 c->data = data;
518 c->next = NULL;
519 user_data = malloc(sizeof(*user_data));
520 user_data->free_func = cpy_destroy_user_data;
521 user_data->data = c;
522 register_function(buf, handler, user_data);
523 return PyString_FromString(buf);
524 }
526 static PyObject *cpy_register_read(PyObject *self, PyObject *args, PyObject *kwds) {
527 char buf[512];
528 cpy_callback_t *c = NULL;
529 user_data_t *user_data = NULL;
530 double interval = 0;
531 const char *name = NULL;
532 PyObject *callback = NULL, *data = NULL;
533 struct timespec ts;
534 static char *kwlist[] = {"callback", "interval", "data", "name", NULL};
536 if (PyArg_ParseTupleAndKeywords(args, kwds, "O|dOz", kwlist, &callback, &interval, &data, &name) == 0) return NULL;
537 if (PyCallable_Check(callback) == 0) {
538 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
539 return NULL;
540 }
541 cpy_build_name(buf, sizeof(buf), callback, name);
543 Py_INCREF(callback);
544 Py_XINCREF(data);
545 c = malloc(sizeof(*c));
546 c->name = strdup(buf);
547 c->callback = callback;
548 c->data = data;
549 c->next = NULL;
550 user_data = malloc(sizeof(*user_data));
551 user_data->free_func = cpy_destroy_user_data;
552 user_data->data = c;
553 ts.tv_sec = interval;
554 ts.tv_nsec = (interval - ts.tv_sec) * 1000000000;
555 plugin_register_complex_read(buf, cpy_read_callback, &ts, user_data);
556 return PyString_FromString(buf);
557 }
559 static PyObject *cpy_register_log(PyObject *self, PyObject *args, PyObject *kwds) {
560 return cpy_register_generic_userdata((void *) plugin_register_log,
561 (void *) cpy_log_callback, args, kwds);
562 }
564 static PyObject *cpy_register_write(PyObject *self, PyObject *args, PyObject *kwds) {
565 return cpy_register_generic_userdata((void *) plugin_register_write,
566 (void *) cpy_write_callback, args, kwds);
567 }
569 static PyObject *cpy_register_notification(PyObject *self, PyObject *args, PyObject *kwds) {
570 return cpy_register_generic_userdata((void *) plugin_register_notification,
571 (void *) cpy_notification_callback, args, kwds);
572 }
574 static PyObject *cpy_register_flush(PyObject *self, PyObject *args, PyObject *kwds) {
575 return cpy_register_generic_userdata((void *) plugin_register_flush,
576 (void *) cpy_flush_callback, args, kwds);
577 }
579 static PyObject *cpy_register_shutdown(PyObject *self, PyObject *args, PyObject *kwds) {
580 return cpy_register_generic(&cpy_shutdown_callbacks, args, kwds);
581 }
583 static PyObject *cpy_error(PyObject *self, PyObject *args) {
584 const char *text;
585 if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
586 Py_BEGIN_ALLOW_THREADS
587 plugin_log(LOG_ERR, "%s", text);
588 Py_END_ALLOW_THREADS
589 Py_RETURN_NONE;
590 }
592 static PyObject *cpy_warning(PyObject *self, PyObject *args) {
593 const char *text;
594 if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
595 Py_BEGIN_ALLOW_THREADS
596 plugin_log(LOG_WARNING, "%s", text);
597 Py_END_ALLOW_THREADS
598 Py_RETURN_NONE;
599 }
601 static PyObject *cpy_notice(PyObject *self, PyObject *args) {
602 const char *text;
603 if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
604 Py_BEGIN_ALLOW_THREADS
605 plugin_log(LOG_NOTICE, "%s", text);
606 Py_END_ALLOW_THREADS
607 Py_RETURN_NONE;
608 }
610 static PyObject *cpy_info(PyObject *self, PyObject *args) {
611 const char *text;
612 if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
613 Py_BEGIN_ALLOW_THREADS
614 plugin_log(LOG_INFO, "%s", text);
615 Py_END_ALLOW_THREADS
616 Py_RETURN_NONE;
617 }
619 static PyObject *cpy_debug(PyObject *self, PyObject *args) {
620 #ifdef COLLECT_DEBUG
621 const char *text;
622 if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
623 Py_BEGIN_ALLOW_THREADS
624 plugin_log(LOG_DEBUG, "%s", text);
625 Py_END_ALLOW_THREADS
626 #endif
627 Py_RETURN_NONE;
628 }
630 static PyObject *cpy_unregister_generic(cpy_callback_t **list_head, PyObject *arg, const char *desc) {
631 char buf[512];
632 const char *name;
633 cpy_callback_t *prev = NULL, *tmp;
635 if (PyUnicode_Check(arg)) {
636 arg = PyUnicode_AsEncodedString(arg, NULL, NULL);
637 if (arg == NULL)
638 return NULL;
639 name = PyString_AsString(arg);
640 Py_DECREF(arg);
641 } else if (PyString_Check(arg)) {
642 name = PyString_AsString(arg);
643 } else {
644 if (!PyCallable_Check(arg)) {
645 PyErr_SetString(PyExc_TypeError, "This function needs a string or a callable object as its only parameter.");
646 return NULL;
647 }
648 cpy_build_name(buf, sizeof(buf), arg, NULL);
649 name = buf;
650 }
651 for (tmp = *list_head; tmp; prev = tmp, tmp = tmp->next)
652 if (strcmp(name, tmp->name) == 0)
653 break;
655 if (tmp == NULL) {
656 PyErr_Format(PyExc_RuntimeError, "Unable to unregister %s callback '%s'.", desc, name);
657 return NULL;
658 }
659 /* Yes, this is actually save. To call this function the caller has to
660 * hold the GIL. Well, save as long as there is only one GIL anyway ... */
661 if (prev == NULL)
662 *list_head = tmp->next;
663 else
664 prev->next = tmp->next;
665 cpy_destroy_user_data(tmp);
666 Py_RETURN_NONE;
667 }
669 typedef int cpy_unregister_function_t(const char *name);
671 static PyObject *cpy_unregister_generic_userdata(cpy_unregister_function_t *unreg, PyObject *arg, const char *desc) {
672 char buf[512];
673 const char *name;
675 if (PyUnicode_Check(arg)) {
676 arg = PyUnicode_AsEncodedString(arg, NULL, NULL);
677 if (arg == NULL)
678 return NULL;
679 name = PyString_AsString(arg);
680 Py_DECREF(arg);
681 } else if (PyString_Check(arg)) {
682 name = PyString_AsString(arg);
683 } else {
684 if (!PyCallable_Check(arg)) {
685 PyErr_SetString(PyExc_TypeError, "This function needs a string or a callable object as its only parameter.");
686 return NULL;
687 }
688 cpy_build_name(buf, sizeof(buf), arg, NULL);
689 name = buf;
690 }
691 if (unreg(name) == 0)
692 Py_RETURN_NONE;
693 PyErr_Format(PyExc_RuntimeError, "Unable to unregister %s callback '%s'.", desc, name);
694 return NULL;
695 }
697 static PyObject *cpy_unregister_log(PyObject *self, PyObject *arg) {
698 return cpy_unregister_generic_userdata(plugin_unregister_log, arg, "log");
699 }
701 static PyObject *cpy_unregister_init(PyObject *self, PyObject *arg) {
702 return cpy_unregister_generic(&cpy_init_callbacks, arg, "init");
703 }
705 static PyObject *cpy_unregister_config(PyObject *self, PyObject *arg) {
706 return cpy_unregister_generic(&cpy_config_callbacks, arg, "config");
707 }
709 static PyObject *cpy_unregister_read(PyObject *self, PyObject *arg) {
710 return cpy_unregister_generic_userdata(plugin_unregister_read, arg, "read");
711 }
713 static PyObject *cpy_unregister_write(PyObject *self, PyObject *arg) {
714 return cpy_unregister_generic_userdata(plugin_unregister_write, arg, "write");
715 }
717 static PyObject *cpy_unregister_notification(PyObject *self, PyObject *arg) {
718 return cpy_unregister_generic_userdata(plugin_unregister_notification, arg, "notification");
719 }
721 static PyObject *cpy_unregister_flush(PyObject *self, PyObject *arg) {
722 return cpy_unregister_generic_userdata(plugin_unregister_flush, arg, "flush");
723 }
725 static PyObject *cpy_unregister_shutdown(PyObject *self, PyObject *arg) {
726 return cpy_unregister_generic(&cpy_shutdown_callbacks, arg, "shutdown");
727 }
729 static PyMethodDef cpy_methods[] = {
730 {"debug", cpy_debug, METH_VARARGS, log_doc},
731 {"info", cpy_info, METH_VARARGS, log_doc},
732 {"notice", cpy_notice, METH_VARARGS, log_doc},
733 {"warning", cpy_warning, METH_VARARGS, log_doc},
734 {"error", cpy_error, METH_VARARGS, log_doc},
735 {"flush", (PyCFunction) cpy_flush, METH_VARARGS | METH_KEYWORDS, flush_doc},
736 {"register_log", (PyCFunction) cpy_register_log, METH_VARARGS | METH_KEYWORDS, reg_log_doc},
737 {"register_init", (PyCFunction) cpy_register_init, METH_VARARGS | METH_KEYWORDS, reg_init_doc},
738 {"register_config", (PyCFunction) cpy_register_config, METH_VARARGS | METH_KEYWORDS, reg_config_doc},
739 {"register_read", (PyCFunction) cpy_register_read, METH_VARARGS | METH_KEYWORDS, reg_read_doc},
740 {"register_write", (PyCFunction) cpy_register_write, METH_VARARGS | METH_KEYWORDS, reg_write_doc},
741 {"register_notification", (PyCFunction) cpy_register_notification, METH_VARARGS | METH_KEYWORDS, reg_notification_doc},
742 {"register_flush", (PyCFunction) cpy_register_flush, METH_VARARGS | METH_KEYWORDS, reg_flush_doc},
743 {"register_shutdown", (PyCFunction) cpy_register_shutdown, METH_VARARGS | METH_KEYWORDS, reg_shutdown_doc},
744 {"unregister_log", cpy_unregister_log, METH_O, unregister_doc},
745 {"unregister_init", cpy_unregister_init, METH_O, unregister_doc},
746 {"unregister_config", cpy_unregister_config, METH_O, unregister_doc},
747 {"unregister_read", cpy_unregister_read, METH_O, unregister_doc},
748 {"unregister_write", cpy_unregister_write, METH_O, unregister_doc},
749 {"unregister_notification", cpy_unregister_notification, METH_O, unregister_doc},
750 {"unregister_flush", cpy_unregister_flush, METH_O, unregister_doc},
751 {"unregister_shutdown", cpy_unregister_shutdown, METH_O, unregister_doc},
752 {0, 0, 0, 0}
753 };
755 static int cpy_shutdown(void) {
756 cpy_callback_t *c;
757 PyObject *ret;
759 /* This can happen if the module was loaded but not configured. */
760 if (state != NULL)
761 PyEval_RestoreThread(state);
763 for (c = cpy_shutdown_callbacks; c; c = c->next) {
764 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
765 if (ret == NULL)
766 cpy_log_exception("shutdown callback");
767 else
768 Py_DECREF(ret);
769 }
770 PyErr_Print();
771 Py_Finalize();
772 return 0;
773 }
775 static void cpy_int_handler(int sig) {
776 return;
777 }
779 static void *cpy_interactive(void *data) {
780 sigset_t sigset;
781 struct sigaction sig_int_action, old;
783 /* Signal handler in a plugin? Bad stuff, but the best way to
784 * handle it I guess. In an interactive session people will
785 * press Ctrl+C at some time, which will generate a SIGINT.
786 * This will cause collectd to shutdown, thus killing the
787 * interactive interpreter, and leaving the terminal in a
788 * mess. Chances are, this isn't what the user wanted to do.
789 *
790 * So this is the plan:
791 * 1. Block SIGINT in the main thread.
792 * 2. Install our own signal handler that does nothing.
793 * 3. Unblock SIGINT in the interactive thread.
794 *
795 * This will make sure that SIGINT won't kill collectd but
796 * still interrupt syscalls like sleep and pause.
797 * It does not raise a KeyboardInterrupt exception because so
798 * far nobody managed to figure out how to do that. */
799 memset (&sig_int_action, '\0', sizeof (sig_int_action));
800 sig_int_action.sa_handler = cpy_int_handler;
801 sigaction (SIGINT, &sig_int_action, &old);
803 sigemptyset(&sigset);
804 sigaddset(&sigset, SIGINT);
805 pthread_sigmask(SIG_UNBLOCK, &sigset, NULL);
806 PyEval_AcquireThread(state);
807 if (PyImport_ImportModule("readline") == NULL) {
808 /* This interactive session will suck. */
809 cpy_log_exception("interactive session init");
810 }
811 PyRun_InteractiveLoop(stdin, "<stdin>");
812 PyErr_Print();
813 PyEval_ReleaseThread(state);
814 NOTICE("python: Interactive interpreter exited, stopping collectd ...");
815 /* Restore the original collectd SIGINT handler and raise SIGINT.
816 * The main thread still has SIGINT blocked and there's nothing we
817 * can do about that so this thread will handle it. But that's not
818 * important, except that it won't interrupt the main loop and so
819 * it might take a few seconds before collectd really shuts down. */
820 sigaction (SIGINT, &old, NULL);
821 raise(SIGINT);
822 pause();
823 return NULL;
824 }
826 static int cpy_init(void) {
827 cpy_callback_t *c;
828 PyObject *ret;
829 static pthread_t thread;
830 sigset_t sigset;
832 PyEval_InitThreads();
833 /* Now it's finally OK to use python threads. */
834 for (c = cpy_init_callbacks; c; c = c->next) {
835 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
836 if (ret == NULL)
837 cpy_log_exception("init callback");
838 else
839 Py_DECREF(ret);
840 }
841 sigemptyset(&sigset);
842 sigaddset(&sigset, SIGINT);
843 pthread_sigmask(SIG_BLOCK, &sigset, NULL);
844 state = PyEval_SaveThread();
845 if (do_interactive) {
846 if (pthread_create(&thread, NULL, cpy_interactive, NULL)) {
847 ERROR("python: Error creating thread for interactive interpreter.");
848 }
849 }
851 return 0;
852 }
854 static PyObject *cpy_oconfig_to_pyconfig(oconfig_item_t *ci, PyObject *parent) {
855 int i;
856 PyObject *item, *values, *children, *tmp;
858 if (parent == NULL)
859 parent = Py_None;
861 values = PyTuple_New(ci->values_num); /* New reference. */
862 for (i = 0; i < ci->values_num; ++i) {
863 if (ci->values[i].type == OCONFIG_TYPE_STRING) {
864 PyTuple_SET_ITEM(values, i, PyString_FromString(ci->values[i].value.string));
865 } else if (ci->values[i].type == OCONFIG_TYPE_NUMBER) {
866 PyTuple_SET_ITEM(values, i, PyFloat_FromDouble(ci->values[i].value.number));
867 } else if (ci->values[i].type == OCONFIG_TYPE_BOOLEAN) {
868 PyTuple_SET_ITEM(values, i, PyBool_FromLong(ci->values[i].value.boolean));
869 }
870 }
872 item = PyObject_CallFunction((void *) &ConfigType, "sONO", ci->key, parent, values, Py_None);
873 if (item == NULL)
874 return NULL;
875 children = PyTuple_New(ci->children_num); /* New reference. */
876 for (i = 0; i < ci->children_num; ++i) {
877 PyTuple_SET_ITEM(children, i, cpy_oconfig_to_pyconfig(ci->children + i, item));
878 }
879 tmp = ((Config *) item)->children;
880 ((Config *) item)->children = children;
881 Py_XDECREF(tmp);
882 return item;
883 }
885 static int cpy_config(oconfig_item_t *ci) {
886 int i;
887 PyObject *sys, *tb;
888 PyObject *sys_path;
889 PyObject *module;
891 /* Ok in theory we shouldn't do initialization at this point
892 * but we have to. In order to give python scripts a chance
893 * to register a config callback we need to be able to execute
894 * python code during the config callback so we have to start
895 * the interpreter here. */
896 /* Do *not* use the python "thread" module at this point! */
897 Py_Initialize();
899 PyType_Ready(&ConfigType);
900 PyType_Ready(&PluginDataType);
901 ValuesType.tp_base = &PluginDataType;
902 PyType_Ready(&ValuesType);
903 NotificationType.tp_base = &PluginDataType;
904 PyType_Ready(&NotificationType);
905 sys = PyImport_ImportModule("sys"); /* New reference. */
906 if (sys == NULL) {
907 cpy_log_exception("python initialization");
908 return 1;
909 }
910 sys_path = PyObject_GetAttrString(sys, "path"); /* New reference. */
911 Py_DECREF(sys);
912 if (sys_path == NULL) {
913 cpy_log_exception("python initialization");
914 return 1;
915 }
916 module = Py_InitModule("collectd", cpy_methods); /* Borrowed reference. */
917 PyModule_AddObject(module, "Config", (void *) &ConfigType); /* Steals a reference. */
918 PyModule_AddObject(module, "Values", (void *) &ValuesType); /* Steals a reference. */
919 PyModule_AddObject(module, "Notification", (void *) &NotificationType); /* Steals a reference. */
920 PyModule_AddIntConstant(module, "LOG_DEBUG", LOG_DEBUG);
921 PyModule_AddIntConstant(module, "LOG_INFO", LOG_INFO);
922 PyModule_AddIntConstant(module, "LOG_NOTICE", LOG_NOTICE);
923 PyModule_AddIntConstant(module, "LOG_WARNING", LOG_WARNING);
924 PyModule_AddIntConstant(module, "LOG_ERROR", LOG_ERR);
925 PyModule_AddIntConstant(module, "NOTIF_FAILURE", NOTIF_FAILURE);
926 PyModule_AddIntConstant(module, "NOTIF_WARNING", NOTIF_WARNING);
927 PyModule_AddIntConstant(module, "NOTIF_OKAY", NOTIF_OKAY);
928 for (i = 0; i < ci->children_num; ++i) {
929 oconfig_item_t *item = ci->children + i;
931 if (strcasecmp(item->key, "Interactive") == 0) {
932 if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_BOOLEAN)
933 continue;
934 do_interactive = item->values[0].value.boolean;
935 } else if (strcasecmp(item->key, "Encoding") == 0) {
936 if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_STRING)
937 continue;
938 /* Why is this even necessary? And undocumented? */
939 if (PyUnicode_SetDefaultEncoding(item->values[0].value.string))
940 cpy_log_exception("setting default encoding");
941 } else if (strcasecmp(item->key, "LogTraces") == 0) {
942 if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_BOOLEAN)
943 continue;
944 if (!item->values[0].value.boolean) {
945 Py_XDECREF(cpy_format_exception);
946 cpy_format_exception = NULL;
947 continue;
948 }
949 if (cpy_format_exception)
950 continue;
951 tb = PyImport_ImportModule("traceback"); /* New reference. */
952 if (tb == NULL) {
953 cpy_log_exception("python initialization");
954 continue;
955 }
956 cpy_format_exception = PyObject_GetAttrString(tb, "format_exception"); /* New reference. */
957 Py_DECREF(tb);
958 if (cpy_format_exception == NULL)
959 cpy_log_exception("python initialization");
960 } else if (strcasecmp(item->key, "ModulePath") == 0) {
961 char *dir = NULL;
962 PyObject *dir_object;
964 if (cf_util_get_string(item, &dir) != 0)
965 continue;
966 dir_object = PyString_FromString(dir); /* New reference. */
967 if (dir_object == NULL) {
968 ERROR("python plugin: Unable to convert \"%s\" to "
969 "a python object.", dir);
970 free(dir);
971 cpy_log_exception("python initialization");
972 continue;
973 }
974 if (PyList_Append(sys_path, dir_object) != 0) {
975 ERROR("python plugin: Unable to append \"%s\" to "
976 "python module path.", dir);
977 cpy_log_exception("python initialization");
978 }
979 Py_DECREF(dir_object);
980 free(dir);
981 } else if (strcasecmp(item->key, "Import") == 0) {
982 char *module_name = NULL;
983 PyObject *module;
985 if (cf_util_get_string(item, &module_name) != 0)
986 continue;
987 module = PyImport_ImportModule(module_name); /* New reference. */
988 if (module == NULL) {
989 ERROR("python plugin: Error importing module \"%s\".", module_name);
990 cpy_log_exception("importing module");
991 PyErr_Print();
992 }
993 free(module_name);
994 Py_XDECREF(module);
995 } else if (strcasecmp(item->key, "Module") == 0) {
996 char *name = NULL;
997 cpy_callback_t *c;
998 PyObject *ret;
1000 if (cf_util_get_string(item, &name) != 0)
1001 continue;
1002 for (c = cpy_config_callbacks; c; c = c->next) {
1003 if (strcasecmp(c->name + 7, name) == 0)
1004 break;
1005 }
1006 if (c == NULL) {
1007 WARNING("python plugin: Found a configuration for the \"%s\" plugin, "
1008 "but the plugin isn't loaded or didn't register "
1009 "a configuration callback.", name);
1010 free(name);
1011 continue;
1012 }
1013 free(name);
1014 if (c->data == NULL)
1015 ret = PyObject_CallFunction(c->callback, "N",
1016 cpy_oconfig_to_pyconfig(item, NULL)); /* New reference. */
1017 else
1018 ret = PyObject_CallFunction(c->callback, "NO",
1019 cpy_oconfig_to_pyconfig(item, NULL), c->data); /* New reference. */
1020 if (ret == NULL)
1021 cpy_log_exception("loading module");
1022 else
1023 Py_DECREF(ret);
1024 } else {
1025 WARNING("python plugin: Ignoring unknown config key \"%s\".", item->key);
1026 }
1027 }
1028 Py_DECREF(sys_path);
1029 return 0;
1030 }
1032 void module_register(void) {
1033 plugin_register_complex_config("python", cpy_config);
1034 plugin_register_init("python", cpy_init);
1035 plugin_register_shutdown("python", cpy_shutdown);
1036 }