16de81d414b1b8ca55867f99fb3b0f77e02e361c
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 Py_DECREF(list);
372 CPY_RETURN_FROM_THREADS 0;
373 }
374 }
375 v = PyObject_CallFunction((void *) &ValuesType, "sOssssdi", value_list->type,
376 list, value_list->plugin_instance, value_list->type_instance,
377 value_list->plugin, value_list->host, (double) value_list->time,
378 value_list->interval); /* New reference. */
379 Py_DECREF(list);
380 ret = PyObject_CallFunctionObjArgs(c->callback, v, c->data, (void *) 0); /* New reference. */
381 Py_XDECREF(v);
382 if (ret == NULL) {
383 cpy_log_exception("write callback");
384 } else {
385 Py_DECREF(ret);
386 }
387 CPY_RELEASE_THREADS
388 return 0;
389 }
391 static int cpy_notification_callback(const notification_t *notification, user_data_t *data) {
392 cpy_callback_t *c = data->data;
393 PyObject *ret, *n;
395 CPY_LOCK_THREADS
396 n = PyObject_CallFunction((void *) &NotificationType, "ssssssdi", notification->type, notification->message,
397 notification->plugin_instance, notification->type_instance, notification->plugin,
398 notification->host, (double) notification->time, notification->severity); /* New reference. */
399 ret = PyObject_CallFunctionObjArgs(c->callback, n, c->data, (void *) 0); /* New reference. */
400 Py_XDECREF(n);
401 if (ret == NULL) {
402 cpy_log_exception("notification callback");
403 } else {
404 Py_DECREF(ret);
405 }
406 CPY_RELEASE_THREADS
407 return 0;
408 }
410 static void cpy_log_callback(int severity, const char *message, user_data_t *data) {
411 cpy_callback_t * c = data->data;
412 PyObject *ret;
414 CPY_LOCK_THREADS
415 if (c->data == NULL)
416 ret = PyObject_CallFunction(c->callback, "is", severity, message); /* New reference. */
417 else
418 ret = PyObject_CallFunction(c->callback, "isO", severity, message, c->data); /* New reference. */
420 if (ret == NULL) {
421 /* FIXME */
422 /* Do we really want to trigger a log callback because a log callback failed?
423 * Probably not. */
424 PyErr_Print();
425 /* In case someone wanted to be clever, replaced stderr and failed at that. */
426 PyErr_Clear();
427 } else {
428 Py_DECREF(ret);
429 }
430 CPY_RELEASE_THREADS
431 }
433 static void cpy_flush_callback(int timeout, const char *id, user_data_t *data) {
434 cpy_callback_t * c = data->data;
435 PyObject *ret;
437 CPY_LOCK_THREADS
438 if (c->data == NULL)
439 ret = PyObject_CallFunction(c->callback, "is", timeout, id); /* New reference. */
440 else
441 ret = PyObject_CallFunction(c->callback, "isO", timeout, id, c->data); /* New reference. */
443 if (ret == NULL) {
444 cpy_log_exception("flush callback");
445 } else {
446 Py_DECREF(ret);
447 }
448 CPY_RELEASE_THREADS
449 }
451 static PyObject *cpy_register_generic(cpy_callback_t **list_head, PyObject *args, PyObject *kwds) {
452 char buf[512];
453 cpy_callback_t *c;
454 const char *name = NULL;
455 PyObject *callback = NULL, *data = NULL, *mod = NULL;
456 static char *kwlist[] = {"callback", "data", "name", NULL};
458 if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oz", kwlist, &callback, &data, &name) == 0) return NULL;
459 if (PyCallable_Check(callback) == 0) {
460 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
461 return NULL;
462 }
463 cpy_build_name(buf, sizeof(buf), callback, name);
465 Py_INCREF(callback);
466 Py_XINCREF(data);
467 c = malloc(sizeof(*c));
468 c->name = strdup(buf);
469 c->callback = callback;
470 c->data = data;
471 c->next = *list_head;
472 *list_head = c;
473 Py_XDECREF(mod);
474 return PyString_FromString(buf);
475 }
477 static PyObject *cpy_flush(cpy_callback_t **list_head, PyObject *args, PyObject *kwds) {
478 int timeout = -1;
479 const char *plugin = NULL, *identifier = NULL;
480 static char *kwlist[] = {"plugin", "timeout", "identifier", NULL};
482 if (PyArg_ParseTupleAndKeywords(args, kwds, "|ziz", kwlist, &plugin, &timeout, &identifier) == 0) return NULL;
483 Py_BEGIN_ALLOW_THREADS
484 plugin_flush(plugin, timeout, identifier);
485 Py_END_ALLOW_THREADS
486 Py_RETURN_NONE;
487 }
489 static PyObject *cpy_register_config(PyObject *self, PyObject *args, PyObject *kwds) {
490 return cpy_register_generic(&cpy_config_callbacks, args, kwds);
491 }
493 static PyObject *cpy_register_init(PyObject *self, PyObject *args, PyObject *kwds) {
494 return cpy_register_generic(&cpy_init_callbacks, args, kwds);
495 }
497 typedef int reg_function_t(const char *name, void *callback, void *data);
499 static PyObject *cpy_register_generic_userdata(void *reg, void *handler, PyObject *args, PyObject *kwds) {
500 char buf[512];
501 reg_function_t *register_function = (reg_function_t *) reg;
502 cpy_callback_t *c = NULL;
503 user_data_t *user_data = NULL;
504 const char *name = NULL;
505 PyObject *callback = NULL, *data = NULL;
506 static char *kwlist[] = {"callback", "data", "name", NULL};
508 if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oz", kwlist, &callback, &data, &name) == 0) return NULL;
509 if (PyCallable_Check(callback) == 0) {
510 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
511 return NULL;
512 }
513 cpy_build_name(buf, sizeof(buf), callback, name);
515 Py_INCREF(callback);
516 Py_XINCREF(data);
517 c = malloc(sizeof(*c));
518 c->name = strdup(buf);
519 c->callback = callback;
520 c->data = data;
521 c->next = NULL;
522 user_data = malloc(sizeof(*user_data));
523 user_data->free_func = cpy_destroy_user_data;
524 user_data->data = c;
525 register_function(buf, handler, user_data);
526 return PyString_FromString(buf);
527 }
529 static PyObject *cpy_register_read(PyObject *self, PyObject *args, PyObject *kwds) {
530 char buf[512];
531 cpy_callback_t *c = NULL;
532 user_data_t *user_data = NULL;
533 double interval = 0;
534 const char *name = NULL;
535 PyObject *callback = NULL, *data = NULL;
536 struct timespec ts;
537 static char *kwlist[] = {"callback", "interval", "data", "name", NULL};
539 if (PyArg_ParseTupleAndKeywords(args, kwds, "O|dOz", kwlist, &callback, &interval, &data, &name) == 0) return NULL;
540 if (PyCallable_Check(callback) == 0) {
541 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
542 return NULL;
543 }
544 cpy_build_name(buf, sizeof(buf), callback, name);
546 Py_INCREF(callback);
547 Py_XINCREF(data);
548 c = malloc(sizeof(*c));
549 c->name = strdup(buf);
550 c->callback = callback;
551 c->data = data;
552 c->next = NULL;
553 user_data = malloc(sizeof(*user_data));
554 user_data->free_func = cpy_destroy_user_data;
555 user_data->data = c;
556 ts.tv_sec = interval;
557 ts.tv_nsec = (interval - ts.tv_sec) * 1000000000;
558 plugin_register_complex_read(buf, cpy_read_callback, &ts, user_data);
559 return PyString_FromString(buf);
560 }
562 static PyObject *cpy_register_log(PyObject *self, PyObject *args, PyObject *kwds) {
563 return cpy_register_generic_userdata((void *) plugin_register_log,
564 (void *) cpy_log_callback, args, kwds);
565 }
567 static PyObject *cpy_register_write(PyObject *self, PyObject *args, PyObject *kwds) {
568 return cpy_register_generic_userdata((void *) plugin_register_write,
569 (void *) cpy_write_callback, args, kwds);
570 }
572 static PyObject *cpy_register_notification(PyObject *self, PyObject *args, PyObject *kwds) {
573 return cpy_register_generic_userdata((void *) plugin_register_notification,
574 (void *) cpy_notification_callback, args, kwds);
575 }
577 static PyObject *cpy_register_flush(PyObject *self, PyObject *args, PyObject *kwds) {
578 return cpy_register_generic_userdata((void *) plugin_register_flush,
579 (void *) cpy_flush_callback, args, kwds);
580 }
582 static PyObject *cpy_register_shutdown(PyObject *self, PyObject *args, PyObject *kwds) {
583 return cpy_register_generic(&cpy_shutdown_callbacks, args, kwds);
584 }
586 static PyObject *cpy_error(PyObject *self, PyObject *args) {
587 const char *text;
588 if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
589 Py_BEGIN_ALLOW_THREADS
590 plugin_log(LOG_ERR, "%s", text);
591 Py_END_ALLOW_THREADS
592 Py_RETURN_NONE;
593 }
595 static PyObject *cpy_warning(PyObject *self, PyObject *args) {
596 const char *text;
597 if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
598 Py_BEGIN_ALLOW_THREADS
599 plugin_log(LOG_WARNING, "%s", text);
600 Py_END_ALLOW_THREADS
601 Py_RETURN_NONE;
602 }
604 static PyObject *cpy_notice(PyObject *self, PyObject *args) {
605 const char *text;
606 if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
607 Py_BEGIN_ALLOW_THREADS
608 plugin_log(LOG_NOTICE, "%s", text);
609 Py_END_ALLOW_THREADS
610 Py_RETURN_NONE;
611 }
613 static PyObject *cpy_info(PyObject *self, PyObject *args) {
614 const char *text;
615 if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
616 Py_BEGIN_ALLOW_THREADS
617 plugin_log(LOG_INFO, "%s", text);
618 Py_END_ALLOW_THREADS
619 Py_RETURN_NONE;
620 }
622 static PyObject *cpy_debug(PyObject *self, PyObject *args) {
623 #ifdef COLLECT_DEBUG
624 const char *text;
625 if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
626 Py_BEGIN_ALLOW_THREADS
627 plugin_log(LOG_DEBUG, "%s", text);
628 Py_END_ALLOW_THREADS
629 #endif
630 Py_RETURN_NONE;
631 }
633 static PyObject *cpy_unregister_generic(cpy_callback_t **list_head, PyObject *arg, const char *desc) {
634 char buf[512];
635 const char *name;
636 cpy_callback_t *prev = NULL, *tmp;
638 if (PyUnicode_Check(arg)) {
639 arg = PyUnicode_AsEncodedString(arg, NULL, NULL);
640 if (arg == NULL)
641 return NULL;
642 name = PyString_AsString(arg);
643 Py_DECREF(arg);
644 } else if (PyString_Check(arg)) {
645 name = PyString_AsString(arg);
646 } else {
647 if (!PyCallable_Check(arg)) {
648 PyErr_SetString(PyExc_TypeError, "This function needs a string or a callable object as its only parameter.");
649 return NULL;
650 }
651 cpy_build_name(buf, sizeof(buf), arg, NULL);
652 name = buf;
653 }
654 for (tmp = *list_head; tmp; prev = tmp, tmp = tmp->next)
655 if (strcmp(name, tmp->name) == 0)
656 break;
658 if (tmp == NULL) {
659 PyErr_Format(PyExc_RuntimeError, "Unable to unregister %s callback '%s'.", desc, name);
660 return NULL;
661 }
662 /* Yes, this is actually save. To call this function the caller has to
663 * hold the GIL. Well, save as long as there is only one GIL anyway ... */
664 if (prev == NULL)
665 *list_head = tmp->next;
666 else
667 prev->next = tmp->next;
668 cpy_destroy_user_data(tmp);
669 Py_RETURN_NONE;
670 }
672 typedef int cpy_unregister_function_t(const char *name);
674 static PyObject *cpy_unregister_generic_userdata(cpy_unregister_function_t *unreg, PyObject *arg, const char *desc) {
675 char buf[512];
676 const char *name;
678 if (PyUnicode_Check(arg)) {
679 arg = PyUnicode_AsEncodedString(arg, NULL, NULL);
680 if (arg == NULL)
681 return NULL;
682 name = PyString_AsString(arg);
683 Py_DECREF(arg);
684 } else if (PyString_Check(arg)) {
685 name = PyString_AsString(arg);
686 } else {
687 if (!PyCallable_Check(arg)) {
688 PyErr_SetString(PyExc_TypeError, "This function needs a string or a callable object as its only parameter.");
689 return NULL;
690 }
691 cpy_build_name(buf, sizeof(buf), arg, NULL);
692 name = buf;
693 }
694 if (unreg(name) == 0)
695 Py_RETURN_NONE;
696 PyErr_Format(PyExc_RuntimeError, "Unable to unregister %s callback '%s'.", desc, name);
697 return NULL;
698 }
700 static PyObject *cpy_unregister_log(PyObject *self, PyObject *arg) {
701 return cpy_unregister_generic_userdata(plugin_unregister_log, arg, "log");
702 }
704 static PyObject *cpy_unregister_init(PyObject *self, PyObject *arg) {
705 return cpy_unregister_generic(&cpy_init_callbacks, arg, "init");
706 }
708 static PyObject *cpy_unregister_config(PyObject *self, PyObject *arg) {
709 return cpy_unregister_generic(&cpy_config_callbacks, arg, "config");
710 }
712 static PyObject *cpy_unregister_read(PyObject *self, PyObject *arg) {
713 return cpy_unregister_generic_userdata(plugin_unregister_read, arg, "read");
714 }
716 static PyObject *cpy_unregister_write(PyObject *self, PyObject *arg) {
717 return cpy_unregister_generic_userdata(plugin_unregister_write, arg, "write");
718 }
720 static PyObject *cpy_unregister_notification(PyObject *self, PyObject *arg) {
721 return cpy_unregister_generic_userdata(plugin_unregister_notification, arg, "notification");
722 }
724 static PyObject *cpy_unregister_flush(PyObject *self, PyObject *arg) {
725 return cpy_unregister_generic_userdata(plugin_unregister_flush, arg, "flush");
726 }
728 static PyObject *cpy_unregister_shutdown(PyObject *self, PyObject *arg) {
729 return cpy_unregister_generic(&cpy_shutdown_callbacks, arg, "shutdown");
730 }
732 static PyMethodDef cpy_methods[] = {
733 {"debug", cpy_debug, METH_VARARGS, log_doc},
734 {"info", cpy_info, METH_VARARGS, log_doc},
735 {"notice", cpy_notice, METH_VARARGS, log_doc},
736 {"warning", cpy_warning, METH_VARARGS, log_doc},
737 {"error", cpy_error, METH_VARARGS, log_doc},
738 {"flush", (PyCFunction) cpy_flush, METH_VARARGS | METH_KEYWORDS, flush_doc},
739 {"register_log", (PyCFunction) cpy_register_log, METH_VARARGS | METH_KEYWORDS, reg_log_doc},
740 {"register_init", (PyCFunction) cpy_register_init, METH_VARARGS | METH_KEYWORDS, reg_init_doc},
741 {"register_config", (PyCFunction) cpy_register_config, METH_VARARGS | METH_KEYWORDS, reg_config_doc},
742 {"register_read", (PyCFunction) cpy_register_read, METH_VARARGS | METH_KEYWORDS, reg_read_doc},
743 {"register_write", (PyCFunction) cpy_register_write, METH_VARARGS | METH_KEYWORDS, reg_write_doc},
744 {"register_notification", (PyCFunction) cpy_register_notification, METH_VARARGS | METH_KEYWORDS, reg_notification_doc},
745 {"register_flush", (PyCFunction) cpy_register_flush, METH_VARARGS | METH_KEYWORDS, reg_flush_doc},
746 {"register_shutdown", (PyCFunction) cpy_register_shutdown, METH_VARARGS | METH_KEYWORDS, reg_shutdown_doc},
747 {"unregister_log", cpy_unregister_log, METH_O, unregister_doc},
748 {"unregister_init", cpy_unregister_init, METH_O, unregister_doc},
749 {"unregister_config", cpy_unregister_config, METH_O, unregister_doc},
750 {"unregister_read", cpy_unregister_read, METH_O, unregister_doc},
751 {"unregister_write", cpy_unregister_write, METH_O, unregister_doc},
752 {"unregister_notification", cpy_unregister_notification, METH_O, unregister_doc},
753 {"unregister_flush", cpy_unregister_flush, METH_O, unregister_doc},
754 {"unregister_shutdown", cpy_unregister_shutdown, METH_O, unregister_doc},
755 {0, 0, 0, 0}
756 };
758 static int cpy_shutdown(void) {
759 cpy_callback_t *c;
760 PyObject *ret;
762 /* This can happen if the module was loaded but not configured. */
763 if (state != NULL)
764 PyEval_RestoreThread(state);
766 for (c = cpy_shutdown_callbacks; c; c = c->next) {
767 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
768 if (ret == NULL)
769 cpy_log_exception("shutdown callback");
770 else
771 Py_DECREF(ret);
772 }
773 PyErr_Print();
774 Py_Finalize();
775 return 0;
776 }
778 static void cpy_int_handler(int sig) {
779 return;
780 }
782 static void *cpy_interactive(void *data) {
783 sigset_t sigset;
784 struct sigaction sig_int_action, old;
786 /* Signal handler in a plugin? Bad stuff, but the best way to
787 * handle it I guess. In an interactive session people will
788 * press Ctrl+C at some time, which will generate a SIGINT.
789 * This will cause collectd to shutdown, thus killing the
790 * interactive interpreter, and leaving the terminal in a
791 * mess. Chances are, this isn't what the user wanted to do.
792 *
793 * So this is the plan:
794 * 1. Block SIGINT in the main thread.
795 * 2. Install our own signal handler that does nothing.
796 * 3. Unblock SIGINT in the interactive thread.
797 *
798 * This will make sure that SIGINT won't kill collectd but
799 * still interrupt syscalls like sleep and pause.
800 * It does not raise a KeyboardInterrupt exception because so
801 * far nobody managed to figure out how to do that. */
802 memset (&sig_int_action, '\0', sizeof (sig_int_action));
803 sig_int_action.sa_handler = cpy_int_handler;
804 sigaction (SIGINT, &sig_int_action, &old);
806 sigemptyset(&sigset);
807 sigaddset(&sigset, SIGINT);
808 pthread_sigmask(SIG_UNBLOCK, &sigset, NULL);
809 PyEval_AcquireThread(state);
810 if (PyImport_ImportModule("readline") == NULL) {
811 /* This interactive session will suck. */
812 cpy_log_exception("interactive session init");
813 }
814 PyRun_InteractiveLoop(stdin, "<stdin>");
815 PyErr_Print();
816 PyEval_ReleaseThread(state);
817 NOTICE("python: Interactive interpreter exited, stopping collectd ...");
818 /* Restore the original collectd SIGINT handler and raise SIGINT.
819 * The main thread still has SIGINT blocked and there's nothing we
820 * can do about that so this thread will handle it. But that's not
821 * important, except that it won't interrupt the main loop and so
822 * it might take a few seconds before collectd really shuts down. */
823 sigaction (SIGINT, &old, NULL);
824 raise(SIGINT);
825 pause();
826 return NULL;
827 }
829 static int cpy_init(void) {
830 cpy_callback_t *c;
831 PyObject *ret;
832 static pthread_t thread;
833 sigset_t sigset;
835 if (!Py_IsInitialized()) {
836 WARNING("python: Plugin loaded but not configured.");
837 plugin_unregister_shutdown("python");
838 return 0;
839 }
840 PyEval_InitThreads();
841 /* Now it's finally OK to use python threads. */
842 for (c = cpy_init_callbacks; c; c = c->next) {
843 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
844 if (ret == NULL)
845 cpy_log_exception("init callback");
846 else
847 Py_DECREF(ret);
848 }
849 sigemptyset(&sigset);
850 sigaddset(&sigset, SIGINT);
851 pthread_sigmask(SIG_BLOCK, &sigset, NULL);
852 state = PyEval_SaveThread();
853 if (do_interactive) {
854 if (pthread_create(&thread, NULL, cpy_interactive, NULL)) {
855 ERROR("python: Error creating thread for interactive interpreter.");
856 }
857 }
859 return 0;
860 }
862 static PyObject *cpy_oconfig_to_pyconfig(oconfig_item_t *ci, PyObject *parent) {
863 int i;
864 PyObject *item, *values, *children, *tmp;
866 if (parent == NULL)
867 parent = Py_None;
869 values = PyTuple_New(ci->values_num); /* New reference. */
870 for (i = 0; i < ci->values_num; ++i) {
871 if (ci->values[i].type == OCONFIG_TYPE_STRING) {
872 PyTuple_SET_ITEM(values, i, PyString_FromString(ci->values[i].value.string));
873 } else if (ci->values[i].type == OCONFIG_TYPE_NUMBER) {
874 PyTuple_SET_ITEM(values, i, PyFloat_FromDouble(ci->values[i].value.number));
875 } else if (ci->values[i].type == OCONFIG_TYPE_BOOLEAN) {
876 PyTuple_SET_ITEM(values, i, PyBool_FromLong(ci->values[i].value.boolean));
877 }
878 }
880 item = PyObject_CallFunction((void *) &ConfigType, "sONO", ci->key, parent, values, Py_None);
881 if (item == NULL)
882 return NULL;
883 children = PyTuple_New(ci->children_num); /* New reference. */
884 for (i = 0; i < ci->children_num; ++i) {
885 PyTuple_SET_ITEM(children, i, cpy_oconfig_to_pyconfig(ci->children + i, item));
886 }
887 tmp = ((Config *) item)->children;
888 ((Config *) item)->children = children;
889 Py_XDECREF(tmp);
890 return item;
891 }
893 static int cpy_config(oconfig_item_t *ci) {
894 int i;
895 char *argv = "";
896 PyObject *sys, *tb;
897 PyObject *sys_path;
898 PyObject *module;
900 /* Ok in theory we shouldn't do initialization at this point
901 * but we have to. In order to give python scripts a chance
902 * to register a config callback we need to be able to execute
903 * python code during the config callback so we have to start
904 * the interpreter here. */
905 /* Do *not* use the python "thread" module at this point! */
906 Py_Initialize();
908 PyType_Ready(&ConfigType);
909 PyType_Ready(&PluginDataType);
910 ValuesType.tp_base = &PluginDataType;
911 PyType_Ready(&ValuesType);
912 NotificationType.tp_base = &PluginDataType;
913 PyType_Ready(&NotificationType);
914 sys = PyImport_ImportModule("sys"); /* New reference. */
915 if (sys == NULL) {
916 cpy_log_exception("python initialization");
917 return 1;
918 }
919 sys_path = PyObject_GetAttrString(sys, "path"); /* New reference. */
920 Py_DECREF(sys);
921 if (sys_path == NULL) {
922 cpy_log_exception("python initialization");
923 return 1;
924 }
925 PySys_SetArgv(1, &argv);
926 PyList_SetSlice(sys_path, 0, 1, NULL);
928 module = Py_InitModule("collectd", cpy_methods); /* Borrowed reference. */
929 PyModule_AddObject(module, "Config", (void *) &ConfigType); /* Steals a reference. */
930 PyModule_AddObject(module, "Values", (void *) &ValuesType); /* Steals a reference. */
931 PyModule_AddObject(module, "Notification", (void *) &NotificationType); /* Steals a reference. */
932 PyModule_AddIntConstant(module, "LOG_DEBUG", LOG_DEBUG);
933 PyModule_AddIntConstant(module, "LOG_INFO", LOG_INFO);
934 PyModule_AddIntConstant(module, "LOG_NOTICE", LOG_NOTICE);
935 PyModule_AddIntConstant(module, "LOG_WARNING", LOG_WARNING);
936 PyModule_AddIntConstant(module, "LOG_ERROR", LOG_ERR);
937 PyModule_AddIntConstant(module, "NOTIF_FAILURE", NOTIF_FAILURE);
938 PyModule_AddIntConstant(module, "NOTIF_WARNING", NOTIF_WARNING);
939 PyModule_AddIntConstant(module, "NOTIF_OKAY", NOTIF_OKAY);
940 for (i = 0; i < ci->children_num; ++i) {
941 oconfig_item_t *item = ci->children + i;
943 if (strcasecmp(item->key, "Interactive") == 0) {
944 if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_BOOLEAN)
945 continue;
946 do_interactive = item->values[0].value.boolean;
947 } else if (strcasecmp(item->key, "Encoding") == 0) {
948 if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_STRING)
949 continue;
950 /* Why is this even necessary? And undocumented? */
951 if (PyUnicode_SetDefaultEncoding(item->values[0].value.string))
952 cpy_log_exception("setting default encoding");
953 } else if (strcasecmp(item->key, "LogTraces") == 0) {
954 if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_BOOLEAN)
955 continue;
956 if (!item->values[0].value.boolean) {
957 Py_XDECREF(cpy_format_exception);
958 cpy_format_exception = NULL;
959 continue;
960 }
961 if (cpy_format_exception)
962 continue;
963 tb = PyImport_ImportModule("traceback"); /* New reference. */
964 if (tb == NULL) {
965 cpy_log_exception("python initialization");
966 continue;
967 }
968 cpy_format_exception = PyObject_GetAttrString(tb, "format_exception"); /* New reference. */
969 Py_DECREF(tb);
970 if (cpy_format_exception == NULL)
971 cpy_log_exception("python initialization");
972 } else if (strcasecmp(item->key, "ModulePath") == 0) {
973 char *dir = NULL;
974 PyObject *dir_object;
976 if (cf_util_get_string(item, &dir) != 0)
977 continue;
978 dir_object = PyString_FromString(dir); /* New reference. */
979 if (dir_object == NULL) {
980 ERROR("python plugin: Unable to convert \"%s\" to "
981 "a python object.", dir);
982 free(dir);
983 cpy_log_exception("python initialization");
984 continue;
985 }
986 if (PyList_Append(sys_path, dir_object) != 0) {
987 ERROR("python plugin: Unable to append \"%s\" to "
988 "python module path.", dir);
989 cpy_log_exception("python initialization");
990 }
991 Py_DECREF(dir_object);
992 free(dir);
993 } else if (strcasecmp(item->key, "Import") == 0) {
994 char *module_name = NULL;
995 PyObject *module;
997 if (cf_util_get_string(item, &module_name) != 0)
998 continue;
999 module = PyImport_ImportModule(module_name); /* New reference. */
1000 if (module == NULL) {
1001 ERROR("python plugin: Error importing module \"%s\".", module_name);
1002 cpy_log_exception("importing module");
1003 PyErr_Print();
1004 }
1005 free(module_name);
1006 Py_XDECREF(module);
1007 } else if (strcasecmp(item->key, "Module") == 0) {
1008 char *name = NULL;
1009 cpy_callback_t *c;
1010 PyObject *ret;
1012 if (cf_util_get_string(item, &name) != 0)
1013 continue;
1014 for (c = cpy_config_callbacks; c; c = c->next) {
1015 if (strcasecmp(c->name + 7, name) == 0)
1016 break;
1017 }
1018 if (c == NULL) {
1019 WARNING("python plugin: Found a configuration for the \"%s\" plugin, "
1020 "but the plugin isn't loaded or didn't register "
1021 "a configuration callback.", name);
1022 free(name);
1023 continue;
1024 }
1025 free(name);
1026 if (c->data == NULL)
1027 ret = PyObject_CallFunction(c->callback, "N",
1028 cpy_oconfig_to_pyconfig(item, NULL)); /* New reference. */
1029 else
1030 ret = PyObject_CallFunction(c->callback, "NO",
1031 cpy_oconfig_to_pyconfig(item, NULL), c->data); /* New reference. */
1032 if (ret == NULL)
1033 cpy_log_exception("loading module");
1034 else
1035 Py_DECREF(ret);
1036 } else {
1037 WARNING("python plugin: Ignoring unknown config key \"%s\".", item->key);
1038 }
1039 }
1040 Py_DECREF(sys_path);
1041 return 0;
1042 }
1044 void module_register(void) {
1045 plugin_register_complex_config("python", cpy_config);
1046 plugin_register_init("python", cpy_init);
1047 plugin_register_shutdown("python", cpy_shutdown);
1048 }