src/python.c

   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  **/
  26
  27 #include <Python.h>
  28 #include <structmember.h>
  29
  30 #include <signal.h>
  31
  32 #include "collectd.h"
  33
  34 #include "common.h"
  35
  36 #include "cpython.h"
  37
  38 typedef struct cpy_callback_s {
  39         char *name;
  40         PyObject *callback;
  41         PyObject *data;
  42         struct cpy_callback_s *next;
  43 } cpy_callback_t;
  44
  45 static char log_doc[] = "This function sends a string to all logging plugins.";
  46
  47 static char get_ds_doc[] = "get_dataset(name) -> definition\n"
  48                 "\n"
  49                 "Returns the definition of a dataset specified by name.\n"
  50                 "\n"
  51                 "'name' is a string specifying the dataset to query.\n"
  52                 "'definition' is a list of 4-tuples. Every tuple represents a \n"
  53                 "    data source within the data set and its 4 values are the \n"
  54                 "    name, type, min and max value.\n"
  55                 "    'name' is a string.\n"
  56                 "    'type' is a string that is equal to either DS_TYPE_COUNTER,\n"
  57                 "        DS_TYPE_GAUGE, DS_TYPE_DERIVE or DS_TYPE_ABSOLUTE.\n"
  58                 "    'min' and 'max' are either a float or None.";
  59
  60 static char flush_doc[] = "flush([plugin][, timeout][, identifier]) -> None\n"
  61                 "\n"
  62                 "Flushes the cache of another plugin.";
  63
  64 static char unregister_doc[] = "Unregisters a callback. This function needs exactly one parameter either\n"
  65                 "the function to unregister or the callback identifier to unregister.";
  66
  67 static char reg_log_doc[] = "register_log(callback[, data][, name]) -> identifier\n"
  68                 "\n"
  69                 "Register a callback function for log messages.\n"
  70                 "\n"
  71                 "'callback' is a callable object that will be called every time something\n"
  72                 "    is logged.\n"
  73                 "'data' is an optional object that will be passed back to the callback\n"
  74                 "    function every time it is called.\n"
  75                 "'name' is an optional identifier for this callback. The default name\n"
  76                 "    is 'python.<module>'.\n"
  77                 "    Every callback needs a unique identifier, so if you want to\n"
  78                 "    register this callback multiple time from the same module you need\n"
  79                 "    to specify a name here.\n"
  80                 "'identifier' is the full identifier assigned to this callback.\n"
  81                 "\n"
  82                 "The callback function will be called with two or three parameters:\n"
  83                 "severity: An integer that should be compared to the LOG_ constants.\n"
  84                 "message: The text to be logged.\n"
  85                 "data: The optional data parameter passed to the register function.\n"
  86                 "    If the parameter was omitted it will be omitted here, too.";
  87
  88 static char reg_init_doc[] = "register_init(callback[, data][, name]) -> identifier\n"
  89                 "\n"
  90                 "Register a callback function that will be executed once after the config.\n"
  91                 "file has been read, all plugins heve been loaded and the collectd has\n"
  92                 "forked into the background.\n"
  93                 "\n"
  94                 "'callback' is a callable object that will be executed.\n"
  95                 "'data' is an optional object that will be passed back to the callback\n"
  96                 "    function when it is called.\n"
  97                 "'name' is an optional identifier for this callback. The default name\n"
  98                 "    is 'python.<module>'.\n"
  99                 "    Every callback needs a unique identifier, so if you want to\n"
 100                 "    register this callback multiple time from the same module you need\n"
 101                 "    to specify a name here.\n"
 102                 "'identifier' is the full identifier assigned to this callback.\n"
 103                 "\n"
 104                 "The callback function will be called without parameters, except for\n"
 105                 "data if it was supplied.";
 106
 107 static char reg_config_doc[] = "register_config(callback[, data][, name]) -> identifier\n"
 108                 "\n"
 109                 "Register a callback function for config file entries.\n"
 110                 "'callback' is a callable object that will be called for every config block.\n"
 111                 "'data' is an optional object that will be passed back to the callback\n"
 112                 "    function every time it is called.\n"
 113                 "'name' is an optional identifier for this callback. The default name\n"
 114                 "    is 'python.<module>'.\n"
 115                 "    Every callback needs a unique identifier, so if you want to\n"
 116                 "    register this callback multiple time from the same module you need\n"
 117                 "    to specify a name here.\n"
 118                 "'identifier' is the full identifier assigned to this callback.\n"
 119                 "\n"
 120                 "The callback function will be called with one or two parameters:\n"
 121                 "config: A Config object.\n"
 122                 "data: The optional data parameter passed to the register function.\n"
 123                 "    If the parameter was omitted it will be omitted here, too.";
 124
 125 static char reg_read_doc[] = "register_read(callback[, interval][, data][, name]) -> identifier\n"
 126                 "\n"
 127                 "Register a callback function for reading data. It will just be called\n"
 128                 "in a fixed interval to signal that it's time to dispatch new values.\n"
 129                 "'callback' is a callable object that will be called every time something\n"
 130                 "    is logged.\n"
 131                 "'interval' is the number of seconds between between calls to the callback\n"
 132                 "    function. Full float precision is supported here.\n"
 133                 "'data' is an optional object that will be passed back to the callback\n"
 134                 "    function every time it is called.\n"
 135                 "'name' is an optional identifier for this callback. The default name\n"
 136                 "    is 'python.<module>'.\n"
 137                 "    Every callback needs a unique identifier, so if you want to\n"
 138                 "    register this callback multiple time from the same module you need\n"
 139                 "    to specify a name here.\n"
 140                 "'identifier' is the full identifier assigned to this callback.\n"
 141                 "\n"
 142                 "The callback function will be called without parameters, except for\n"
 143                 "data if it was supplied.";
 144
 145 static char reg_write_doc[] = "register_write(callback[, data][, name]) -> identifier\n"
 146                 "\n"
 147                 "Register a callback function to receive values dispatched by other plugins.\n"
 148                 "'callback' is a callable object that will be called every time a value\n"
 149                 "    is dispatched.\n"
 150                 "'data' is an optional object that will be passed back to the callback\n"
 151                 "    function every time it is called.\n"
 152                 "'name' is an optional identifier for this callback. The default name\n"
 153                 "    is 'python.<module>'.\n"
 154                 "    Every callback needs a unique identifier, so if you want to\n"
 155                 "    register this callback multiple time from the same module you need\n"
 156                 "    to specify a name here.\n"
 157                 "'identifier' is the full identifier assigned to this callback.\n"
 158                 "\n"
 159                 "The callback function will be called with one or two parameters:\n"
 160                 "values: A Values object which is a copy of the dispatched values.\n"
 161                 "data: The optional data parameter passed to the register function.\n"
 162                 "    If the parameter was omitted it will be omitted here, too.";
 163
 164 static char reg_notification_doc[] = "register_notification(callback[, data][, name]) -> identifier\n"
 165                 "\n"
 166                 "Register a callback function for notifications.\n"
 167                 "'callback' is a callable object that will be called every time a notification\n"
 168                 "    is dispatched.\n"
 169                 "'data' is an optional object that will be passed back to the callback\n"
 170                 "    function every time it is called.\n"
 171                 "'name' is an optional identifier for this callback. The default name\n"
 172                 "    is 'python.<module>'.\n"
 173                 "    Every callback needs a unique identifier, so if you want to\n"
 174                 "    register this callback multiple time from the same module you need\n"
 175                 "    to specify a name here.\n"
 176                 "'identifier' is the full identifier assigned to this callback.\n"
 177                 "\n"
 178                 "The callback function will be called with one or two parameters:\n"
 179                 "notification: A copy of the notification that was dispatched.\n"
 180                 "data: The optional data parameter passed to the register function.\n"
 181                 "    If the parameter was omitted it will be omitted here, too.";
 182
 183 static char reg_flush_doc[] = "register_flush(callback[, data][, name]) -> identifier\n"
 184                 "\n"
 185                 "Register a callback function for flush messages.\n"
 186                 "'callback' is a callable object that will be called every time a plugin\n"
 187                 "    requests a flush for either this or all plugins.\n"
 188                 "'data' is an optional object that will be passed back to the callback\n"
 189                 "    function every time it is called.\n"
 190                 "'name' is an optional identifier for this callback. The default name\n"
 191                 "    is 'python.<module>'.\n"
 192                 "    Every callback needs a unique identifier, so if you want to\n"
 193                 "    register this callback multiple time from the same module you need\n"
 194                 "    to specify a name here.\n"
 195                 "'identifier' is the full identifier assigned to this callback.\n"
 196                 "\n"
 197                 "The callback function will be called with two or three parameters:\n"
 198                 "timeout: Indicates that only data older than 'timeout' seconds is to\n"
 199                 "    be flushed.\n"
 200                 "id: Specifies which values are to be flushed.\n"
 201                 "data: The optional data parameter passed to the register function.\n"
 202                 "    If the parameter was omitted it will be omitted here, too.";
 203
 204 static char reg_shutdown_doc[] = "register_shutdown(callback[, data][, name]) -> identifier\n"
 205                 "\n"
 206                 "Register a callback function for collectd shutdown.\n"
 207                 "'callback' is a callable object that will be called once collectd is\n"
 208                 "    shutting down.\n"
 209                 "'data' is an optional object that will be passed back to the callback\n"
 210                 "    function if it is called.\n"
 211                 "'name' is an optional identifier for this callback. The default name\n"
 212                 "    is 'python.<module>'.\n"
 213                 "    Every callback needs a unique identifier, so if you want to\n"
 214                 "    register this callback multiple time from the same module you need\n"
 215                 "    to specify a name here.\n"
 216                 "'identifier' is the full identifier assigned to this callback.\n"
 217                 "\n"
 218                 "The callback function will be called with no parameters except for\n"
 219                 "    data if it was supplied.";
 220
 221
 222 static pthread_t main_thread;
 223 static PyOS_sighandler_t python_sigint_handler;
 224 static _Bool do_interactive = 0;
 225
 226 /* This is our global thread state. Python saves some stuff in thread-local
 227  * storage. So if we allow the interpreter to run in the background
 228  * (the scriptwriters might have created some threads from python), we have
 229  * to save the state so we can resume it later after shutdown. */
 230
 231 static PyThreadState *state;
 232
 233 static PyObject *sys_path, *cpy_format_exception;
 234
 235 static cpy_callback_t *cpy_config_callbacks;
 236 static cpy_callback_t *cpy_init_callbacks;
 237 static cpy_callback_t *cpy_shutdown_callbacks;
 238
 239 static void cpy_destroy_user_data(void *data) {
 240         cpy_callback_t *c = data;
 241         free(c->name);
 242         Py_DECREF(c->callback);
 243         Py_XDECREF(c->data);
 244         free(c);
 245 }
 246
 247 /* You must hold the GIL to call this function!
 248  * But if you managed to extract the callback parameter then you probably already do. */
 249
 250 static void cpy_build_name(char *buf, size_t size, PyObject *callback, const char *name) {
 251         const char *module = NULL;
 252         PyObject *mod = NULL;
 253
 254         if (name != NULL) {
 255                 snprintf(buf, size, "python.%s", name);
 256                 return;
 257         }
 258
 259         mod = PyObject_GetAttrString(callback, "__module__"); /* New reference. */
 260         if (mod != NULL)
 261                 module = cpy_unicode_or_bytes_to_string(&mod);
 262
 263         if (module != NULL) {
 264                 snprintf(buf, size, "python.%s", module);
 265                 Py_XDECREF(mod);
 266                 PyErr_Clear();
 267                 return;
 268         }
 269         Py_XDECREF(mod);
 270
 271         snprintf(buf, size, "python.%p", callback);
 272         PyErr_Clear();
 273 }
 274
 275 void cpy_log_exception(const char *context) {
 276         int l = 0;
 277         const char *typename = NULL, *message = NULL;
 278         PyObject *type, *value, *traceback, *tn, *m, *list;
 279
 280         PyErr_Fetch(&type, &value, &traceback);
 281         PyErr_NormalizeException(&type, &value, &traceback);
 282         if (type == NULL) return;
 283         tn = PyObject_GetAttrString(type, "__name__"); /* New reference. */
 284         m = PyObject_Str(value); /* New reference. */
 285         if (tn != NULL)
 286                 typename = cpy_unicode_or_bytes_to_string(&tn);
 287         if (m != NULL)
 288                 message = cpy_unicode_or_bytes_to_string(&m);
 289         if (typename == NULL)
 290                 typename = "NamelessException";
 291         if (message == NULL)
 292                 message = "N/A";
 293         Py_BEGIN_ALLOW_THREADS
 294         ERROR("Unhandled python exception in %s: %s: %s", context, typename, message);
 295         Py_END_ALLOW_THREADS
 296         Py_XDECREF(tn);
 297         Py_XDECREF(m);
 298         if (!cpy_format_exception || !traceback) {
 299                 PyErr_Clear();
 300                 Py_DECREF(type);
 301                 Py_XDECREF(value);
 302                 Py_XDECREF(traceback);
 303                 return;
 304         }
 305         list = PyObject_CallFunction(cpy_format_exception, "NNN", type, value, traceback); /* New reference. Steals references from "type", "value" and "traceback". */
 306         if (list)
 307                 l = PyObject_Length(list);
 308
 309         for (int i = 0; i < l; ++i) {
 310                 PyObject *line;
 311                 char const *msg;
 312                 char *cpy;
 313
 314                 line = PyList_GET_ITEM(list, i); /* Borrowed reference. */
 315                 Py_INCREF(line);
 316
 317                 msg = cpy_unicode_or_bytes_to_string(&line);
 318                 Py_DECREF(line);
 319                 if (msg == NULL)
 320                         continue;
 321
 322                 cpy = strdup(msg);
 323                 if (cpy == NULL)
 324                         continue;
 325
 326                 if (cpy[strlen(cpy) - 1] == '\n')
 327                         cpy[strlen(cpy) - 1] = 0;
 328
 329                 Py_BEGIN_ALLOW_THREADS
 330                 ERROR("%s", cpy);
 331                 Py_END_ALLOW_THREADS
 332
 333                 free(cpy);
 334         }
 335
 336         Py_XDECREF(list);
 337         PyErr_Clear();
 338 }
 339
 340 static int cpy_read_callback(user_data_t *data) {
 341         cpy_callback_t *c = data->data;
 342         PyObject *ret;
 343
 344         CPY_LOCK_THREADS
 345                 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
 346                 if (ret == NULL) {
 347                         cpy_log_exception("read callback");
 348                 } else {
 349                         Py_DECREF(ret);
 350                 }
 351         CPY_RELEASE_THREADS
 352         if (ret == NULL)
 353                 return 1;
 354         return 0;
 355 }
 356
 357 static int cpy_write_callback(const data_set_t *ds, const value_list_t *value_list, user_data_t *data) {
 358         cpy_callback_t *c = data->data;
 359         PyObject *ret, *list, *temp, *dict = NULL;
 360         Values *v;
 361
 362         CPY_LOCK_THREADS
 363                 list = PyList_New(value_list->values_len); /* New reference. */
 364                 if (list == NULL) {
 365                         cpy_log_exception("write callback");
 366                         CPY_RETURN_FROM_THREADS 0;
 367                 }
 368                 for (size_t i = 0; i < value_list->values_len; ++i) {
 369                         if (ds->ds[i].type == DS_TYPE_COUNTER) {
 370                                 PyList_SetItem(list, i, PyLong_FromUnsignedLongLong(value_list->values[i].counter));
 371                         } else if (ds->ds[i].type == DS_TYPE_GAUGE) {
 372                                 PyList_SetItem(list, i, PyFloat_FromDouble(value_list->values[i].gauge));
 373                         } else if (ds->ds[i].type == DS_TYPE_DERIVE) {
 374                                 PyList_SetItem(list, i, PyLong_FromLongLong(value_list->values[i].derive));
 375                         } else if (ds->ds[i].type == DS_TYPE_ABSOLUTE) {
 376                                 PyList_SetItem(list, i, PyLong_FromUnsignedLongLong(value_list->values[i].absolute));
 377                         } else {
 378                                 Py_BEGIN_ALLOW_THREADS
 379                                 ERROR("cpy_write_callback: Unknown value type %d.", ds->ds[i].type);
 380                                 Py_END_ALLOW_THREADS
 381                                 Py_DECREF(list);
 382                                 CPY_RETURN_FROM_THREADS 0;
 383                         }
 384                         if (PyErr_Occurred() != NULL) {
 385                                 cpy_log_exception("value building for write callback");
 386                                 Py_DECREF(list);
 387                                 CPY_RETURN_FROM_THREADS 0;
 388                         }
 389                 }
 390                 dict = PyDict_New();  /* New reference. */
 391                 if (value_list->meta) {
 392                         int num;
 393                         char **table;
 394                         meta_data_t *meta = value_list->meta;
 395
 396                         num = meta_data_toc(meta, &table);
 397                         for (size_t i = 0; i < num; ++i) {
 398                                 int type;
 399                                 char *string;
 400                                 int64_t si;
 401                                 uint64_t ui;
 402                                 double d;
 403                                 _Bool b;
 404
 405                                 type = meta_data_type(meta, table[i]);
 406                                 if (type == MD_TYPE_STRING) {
 407                                         if (meta_data_get_string(meta, table[i], &string))
 408                                                 continue;
 409                                         temp = cpy_string_to_unicode_or_bytes(string);  /* New reference. */
 410                                         free(string);
 411                                         PyDict_SetItemString(dict, table[i], temp);
 412                                         Py_XDECREF(temp);
 413                                 } else if (type == MD_TYPE_SIGNED_INT) {
 414                                         if (meta_data_get_signed_int(meta, table[i], &si))
 415                                                 continue;
 416                                         temp = PyObject_CallFunctionObjArgs((void *) &SignedType, PyLong_FromLongLong(si), (void *) 0);  /* New reference. */
 417                                         PyDict_SetItemString(dict, table[i], temp);
 418                                         Py_XDECREF(temp);
 419                                 } else if (type == MD_TYPE_UNSIGNED_INT) {
 420                                         if (meta_data_get_unsigned_int(meta, table[i], &ui))
 421                                                 continue;
 422                                         temp = PyObject_CallFunctionObjArgs((void *) &UnsignedType, PyLong_FromUnsignedLongLong(ui), (void *) 0);  /* New reference. */
 423                                         PyDict_SetItemString(dict, table[i], temp);
 424                                         Py_XDECREF(temp);
 425                                 } else if (type == MD_TYPE_DOUBLE) {
 426                                         if (meta_data_get_double(meta, table[i], &d))
 427                                                 continue;
 428                                         temp = PyFloat_FromDouble(d);  /* New reference. */
 429                                         PyDict_SetItemString(dict, table[i], temp);
 430                                         Py_XDECREF(temp);
 431                                 } else if (type == MD_TYPE_BOOLEAN) {
 432                                         if (meta_data_get_boolean(meta, table[i], &b))
 433                                                 continue;
 434                                         if (b)
 435                                                 PyDict_SetItemString(dict, table[i], Py_True);
 436                                         else
 437                                                 PyDict_SetItemString(dict, table[i], Py_False);
 438                                 }
 439                                 free(table[i]);
 440                         }
 441                         free(table);
 442                 }
 443                 v = (Values *) Values_New(); /* New reference. */
 444                 sstrncpy(v->data.host, value_list->host, sizeof(v->data.host));
 445                 sstrncpy(v->data.type, value_list->type, sizeof(v->data.type));
 446                 sstrncpy(v->data.type_instance, value_list->type_instance, sizeof(v->data.type_instance));
 447                 sstrncpy(v->data.plugin, value_list->plugin, sizeof(v->data.plugin));
 448                 sstrncpy(v->data.plugin_instance, value_list->plugin_instance, sizeof(v->data.plugin_instance));
 449                 v->data.time = CDTIME_T_TO_DOUBLE(value_list->time);
 450                 v->interval = CDTIME_T_TO_DOUBLE(value_list->interval);
 451                 Py_CLEAR(v->values);
 452                 v->values = list;
 453                 Py_CLEAR(v->meta);
 454                 v->meta = dict;  /* Steals a reference. */
 455                 ret = PyObject_CallFunctionObjArgs(c->callback, v, c->data, (void *) 0); /* New reference. */
 456                 Py_XDECREF(v);
 457                 if (ret == NULL) {
 458                         cpy_log_exception("write callback");
 459                 } else {
 460                         Py_DECREF(ret);
 461                 }
 462         CPY_RELEASE_THREADS
 463         return 0;
 464 }
 465
 466 static int cpy_notification_callback(const notification_t *notification, user_data_t *data) {
 467         cpy_callback_t *c = data->data;
 468         PyObject *ret, *notify;
 469         Notification *n;
 470
 471         CPY_LOCK_THREADS
 472                 notify = Notification_New(); /* New reference. */
 473                 n = (Notification *) notify;
 474                 sstrncpy(n->data.host, notification->host, sizeof(n->data.host));
 475                 sstrncpy(n->data.type, notification->type, sizeof(n->data.type));
 476                 sstrncpy(n->data.type_instance, notification->type_instance, sizeof(n->data.type_instance));
 477                 sstrncpy(n->data.plugin, notification->plugin, sizeof(n->data.plugin));
 478                 sstrncpy(n->data.plugin_instance, notification->plugin_instance, sizeof(n->data.plugin_instance));
 479                 n->data.time = CDTIME_T_TO_DOUBLE(notification->time);
 480                 sstrncpy(n->message, notification->message, sizeof(n->message));
 481                 n->severity = notification->severity;
 482                 ret = PyObject_CallFunctionObjArgs(c->callback, n, c->data, (void *) 0); /* New reference. */
 483                 Py_XDECREF(notify);
 484                 if (ret == NULL) {
 485                         cpy_log_exception("notification callback");
 486                 } else {
 487                         Py_DECREF(ret);
 488                 }
 489         CPY_RELEASE_THREADS
 490         return 0;
 491 }
 492
 493 static void cpy_log_callback(int severity, const char *message, user_data_t *data) {
 494         cpy_callback_t * c = data->data;
 495         PyObject *ret, *text;
 496
 497         CPY_LOCK_THREADS
 498         text = cpy_string_to_unicode_or_bytes(message);  /* New reference. */
 499         if (c->data == NULL)
 500                 ret = PyObject_CallFunction(c->callback, "iN", severity, text); /* New reference. Steals a reference from "text". */
 501         else
 502                 ret = PyObject_CallFunction(c->callback, "iNO", severity, text, c->data); /* New reference. Steals a reference from "text". */
 503
 504         if (ret == NULL) {
 505                 /* FIXME */
 506                 /* Do we really want to trigger a log callback because a log callback failed?
 507                  * Probably not. */
 508                 PyErr_Print();
 509                 /* In case someone wanted to be clever, replaced stderr and failed at that. */
 510                 PyErr_Clear();
 511         } else {
 512                 Py_DECREF(ret);
 513         }
 514         CPY_RELEASE_THREADS
 515 }
 516
 517 static void cpy_flush_callback(int timeout, const char *id, user_data_t *data) {
 518         cpy_callback_t * c = data->data;
 519         PyObject *ret, *text;
 520
 521         CPY_LOCK_THREADS
 522         text = cpy_string_to_unicode_or_bytes(id);
 523         if (c->data == NULL)
 524                 ret = PyObject_CallFunction(c->callback, "iN", timeout, text); /* New reference. */
 525         else
 526                 ret = PyObject_CallFunction(c->callback, "iNO", timeout, text, c->data); /* New reference. */
 527
 528         if (ret == NULL) {
 529                 cpy_log_exception("flush callback");
 530         } else {
 531                 Py_DECREF(ret);
 532         }
 533         CPY_RELEASE_THREADS
 534 }
 535
 536 static PyObject *cpy_register_generic(cpy_callback_t **list_head, PyObject *args, PyObject *kwds) {
 537         char buf[512];
 538         cpy_callback_t *c;
 539         char *name = NULL;
 540         PyObject *callback = NULL, *data = NULL, *mod = NULL;
 541         static char *kwlist[] = {"callback", "data", "name", NULL};
 542
 543         if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oet", kwlist, &callback, &data, NULL, &name) == 0) return NULL;
 544         if (PyCallable_Check(callback) == 0) {
 545                 PyMem_Free(name);
 546                 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
 547                 return NULL;
 548         }
 549         cpy_build_name(buf, sizeof(buf), callback, name);
 550
 551         Py_INCREF(callback);
 552         Py_XINCREF(data);
 553
 554         c = calloc(1, sizeof(*c));
 555         if (c == NULL)
 556                 return NULL;
 557
 558         c->name = strdup(buf);
 559         c->callback = callback;
 560         c->data = data;
 561         c->next = *list_head;
 562         *list_head = c;
 563         Py_XDECREF(mod);
 564         PyMem_Free(name);
 565         return cpy_string_to_unicode_or_bytes(buf);
 566 }
 567
 568 static PyObject *float_or_none(float number) {
 569         if (isnan(number)) {
 570                 Py_RETURN_NONE;
 571         }
 572         return PyFloat_FromDouble(number);
 573 }
 574
 575 static PyObject *cpy_get_dataset(PyObject *self, PyObject *args) {
 576         char *name;
 577         const data_set_t *ds;
 578         PyObject *list, *tuple;
 579
 580         if (PyArg_ParseTuple(args, "et", NULL, &name) == 0) return NULL;
 581         ds = plugin_get_ds(name);
 582         PyMem_Free(name);
 583         if (ds == NULL) {
 584                 PyErr_Format(PyExc_TypeError, "Dataset %s not found", name);
 585                 return NULL;
 586         }
 587         list = PyList_New(ds->ds_num); /* New reference. */
 588         for (size_t i = 0; i < ds->ds_num; ++i) {
 589                 tuple = PyTuple_New(4);
 590                 PyTuple_SET_ITEM(tuple, 0, cpy_string_to_unicode_or_bytes(ds->ds[i].name));
 591                 PyTuple_SET_ITEM(tuple, 1, cpy_string_to_unicode_or_bytes(DS_TYPE_TO_STRING(ds->ds[i].type)));
 592                 PyTuple_SET_ITEM(tuple, 2, float_or_none(ds->ds[i].min));
 593                 PyTuple_SET_ITEM(tuple, 3, float_or_none(ds->ds[i].max));
 594                 PyList_SET_ITEM(list, i, tuple);
 595         }
 596         return list;
 597 }
 598
 599 static PyObject *cpy_flush(PyObject *self, PyObject *args, PyObject *kwds) {
 600         int timeout = -1;
 601         char *plugin = NULL, *identifier = NULL;
 602         static char *kwlist[] = {"plugin", "timeout", "identifier", NULL};
 603
 604         if (PyArg_ParseTupleAndKeywords(args, kwds, "|etiet", kwlist, NULL, &plugin, &timeout, NULL, &identifier) == 0) return NULL;
 605         Py_BEGIN_ALLOW_THREADS
 606         plugin_flush(plugin, timeout, identifier);
 607         Py_END_ALLOW_THREADS
 608         PyMem_Free(plugin);
 609         PyMem_Free(identifier);
 610         Py_RETURN_NONE;
 611 }
 612
 613 static PyObject *cpy_register_config(PyObject *self, PyObject *args, PyObject *kwds) {
 614         return cpy_register_generic(&cpy_config_callbacks, args, kwds);
 615 }
 616
 617 static PyObject *cpy_register_init(PyObject *self, PyObject *args, PyObject *kwds) {
 618         return cpy_register_generic(&cpy_init_callbacks, args, kwds);
 619 }
 620
 621 typedef int reg_function_t(const char *name, void *callback, void *data);
 622
 623 static PyObject *cpy_register_generic_userdata(void *reg, void *handler, PyObject *args, PyObject *kwds) {
 624         char buf[512];
 625         reg_function_t *register_function = (reg_function_t *) reg;
 626         cpy_callback_t *c = NULL;
 627         char *name = NULL;
 628         PyObject *callback = NULL, *data = NULL;
 629         static char *kwlist[] = {"callback", "data", "name", NULL};
 630
 631         if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oet", kwlist, &callback, &data, NULL, &name) == 0) return NULL;
 632         if (PyCallable_Check(callback) == 0) {
 633                 PyMem_Free(name);
 634                 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
 635                 return NULL;
 636         }
 637         cpy_build_name(buf, sizeof(buf), callback, name);
 638         PyMem_Free(name);
 639
 640         Py_INCREF(callback);
 641         Py_XINCREF(data);
 642
 643         c = calloc(1, sizeof(*c));
 644         if (c == NULL)
 645                 return NULL;
 646
 647         c->name = strdup(buf);
 648         c->callback = callback;
 649         c->data = data;
 650         c->next = NULL;
 651
 652         user_data_t user_data = {
 653                 .data = c,
 654                 .free_func = cpy_destroy_user_data
 655         };
 656
 657         register_function(buf, handler, &user_data);
 658         return cpy_string_to_unicode_or_bytes(buf);
 659 }
 660
 661 static PyObject *cpy_register_read(PyObject *self, PyObject *args, PyObject *kwds) {
 662         char buf[512];
 663         cpy_callback_t *c = NULL;
 664         double interval = 0;
 665         char *name = NULL;
 666         PyObject *callback = NULL, *data = NULL;
 667         static char *kwlist[] = {"callback", "interval", "data", "name", NULL};
 668
 669         if (PyArg_ParseTupleAndKeywords(args, kwds, "O|dOet", kwlist, &callback, &interval, &data, NULL, &name) == 0) return NULL;
 670         if (PyCallable_Check(callback) == 0) {
 671                 PyMem_Free(name);
 672                 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
 673                 return NULL;
 674         }
 675         cpy_build_name(buf, sizeof(buf), callback, name);
 676         PyMem_Free(name);
 677
 678         Py_INCREF(callback);
 679         Py_XINCREF(data);
 680
 681         c = calloc(1, sizeof(*c));
 682         if (c == NULL)
 683                 return NULL;
 684
 685         c->name = strdup(buf);
 686         c->callback = callback;
 687         c->data = data;
 688         c->next = NULL;
 689
 690         user_data_t user_data = {
 691                 .data = c,
 692                 .free_func = cpy_destroy_user_data
 693         };
 694
 695         plugin_register_complex_read(/* group = */ "python", buf,
 696                         cpy_read_callback, DOUBLE_TO_CDTIME_T (interval), &user_data);
 697         return cpy_string_to_unicode_or_bytes(buf);
 698 }
 699
 700 static PyObject *cpy_register_log(PyObject *self, PyObject *args, PyObject *kwds) {
 701         return cpy_register_generic_userdata((void *) plugin_register_log,
 702                         (void *) cpy_log_callback, args, kwds);
 703 }
 704
 705 static PyObject *cpy_register_write(PyObject *self, PyObject *args, PyObject *kwds) {
 706         return cpy_register_generic_userdata((void *) plugin_register_write,
 707                         (void *) cpy_write_callback, args, kwds);
 708 }
 709
 710 static PyObject *cpy_register_notification(PyObject *self, PyObject *args, PyObject *kwds) {
 711         return cpy_register_generic_userdata((void *) plugin_register_notification,
 712                         (void *) cpy_notification_callback, args, kwds);
 713 }
 714
 715 static PyObject *cpy_register_flush(PyObject *self, PyObject *args, PyObject *kwds) {
 716         return cpy_register_generic_userdata((void *) plugin_register_flush,
 717                         (void *) cpy_flush_callback, args, kwds);
 718 }
 719
 720 static PyObject *cpy_register_shutdown(PyObject *self, PyObject *args, PyObject *kwds) {
 721         return cpy_register_generic(&cpy_shutdown_callbacks, args, kwds);
 722 }
 723
 724 static PyObject *cpy_error(PyObject *self, PyObject *args) {
 725         char *text;
 726         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 727         Py_BEGIN_ALLOW_THREADS
 728         plugin_log(LOG_ERR, "%s", text);
 729         Py_END_ALLOW_THREADS
 730         PyMem_Free(text);
 731         Py_RETURN_NONE;
 732 }
 733
 734 static PyObject *cpy_warning(PyObject *self, PyObject *args) {
 735         char *text;
 736         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 737         Py_BEGIN_ALLOW_THREADS
 738         plugin_log(LOG_WARNING, "%s", text);
 739         Py_END_ALLOW_THREADS
 740         PyMem_Free(text);
 741         Py_RETURN_NONE;
 742 }
 743
 744 static PyObject *cpy_notice(PyObject *self, PyObject *args) {
 745         char *text;
 746         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 747         Py_BEGIN_ALLOW_THREADS
 748         plugin_log(LOG_NOTICE, "%s", text);
 749         Py_END_ALLOW_THREADS
 750         PyMem_Free(text);
 751         Py_RETURN_NONE;
 752 }
 753
 754 static PyObject *cpy_info(PyObject *self, PyObject *args) {
 755         char *text;
 756         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 757         Py_BEGIN_ALLOW_THREADS
 758         plugin_log(LOG_INFO, "%s", text);
 759         Py_END_ALLOW_THREADS
 760         PyMem_Free(text);
 761         Py_RETURN_NONE;
 762 }
 763
 764 static PyObject *cpy_debug(PyObject *self, PyObject *args) {
 765 #ifdef COLLECT_DEBUG
 766         char *text;
 767         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 768         Py_BEGIN_ALLOW_THREADS
 769         plugin_log(LOG_DEBUG, "%s", text);
 770         Py_END_ALLOW_THREADS
 771         PyMem_Free(text);
 772 #endif
 773         Py_RETURN_NONE;
 774 }
 775
 776 static PyObject *cpy_unregister_generic(cpy_callback_t **list_head, PyObject *arg, const char *desc) {
 777         char buf[512];
 778         const char *name;
 779         cpy_callback_t *prev = NULL, *tmp;
 780
 781         Py_INCREF(arg);
 782         name = cpy_unicode_or_bytes_to_string(&arg);
 783         if (name == NULL) {
 784                 PyErr_Clear();
 785                 if (!PyCallable_Check(arg)) {
 786                         PyErr_SetString(PyExc_TypeError, "This function needs a string or a callable object as its only parameter.");
 787                         Py_DECREF(arg);
 788                         return NULL;
 789                 }
 790                 cpy_build_name(buf, sizeof(buf), arg, NULL);
 791                 name = buf;
 792         }
 793         for (tmp = *list_head; tmp; prev = tmp, tmp = tmp->next)
 794                 if (strcmp(name, tmp->name) == 0)
 795                         break;
 796
 797         Py_DECREF(arg);
 798         if (tmp == NULL) {
 799                 PyErr_Format(PyExc_RuntimeError, "Unable to unregister %s callback '%s'.", desc, name);
 800                 return NULL;
 801         }
 802         /* Yes, this is actually save. To call this function the caller has to
 803          * hold the GIL. Well, save as long as there is only one GIL anyway ... */
 804         if (prev == NULL)
 805                 *list_head = tmp->next;
 806         else
 807                 prev->next = tmp->next;
 808         cpy_destroy_user_data(tmp);
 809         Py_RETURN_NONE;
 810 }
 811
 812 typedef int cpy_unregister_function_t(const char *name);
 813
 814 static PyObject *cpy_unregister_generic_userdata(cpy_unregister_function_t *unreg, PyObject *arg, const char *desc) {
 815         char buf[512];
 816         const char *name;
 817
 818         Py_INCREF(arg);
 819         name = cpy_unicode_or_bytes_to_string(&arg);
 820         if (name == NULL) {
 821                 PyErr_Clear();
 822                 if (!PyCallable_Check(arg)) {
 823                         PyErr_SetString(PyExc_TypeError, "This function needs a string or a callable object as its only parameter.");
 824                         Py_DECREF(arg);
 825                         return NULL;
 826                 }
 827                 cpy_build_name(buf, sizeof(buf), arg, NULL);
 828                 name = buf;
 829         }
 830         if (unreg(name) == 0) {
 831                 Py_DECREF(arg);
 832                 Py_RETURN_NONE;
 833         }
 834         PyErr_Format(PyExc_RuntimeError, "Unable to unregister %s callback '%s'.", desc, name);
 835         Py_DECREF(arg);
 836         return NULL;
 837 }
 838
 839 static PyObject *cpy_unregister_log(PyObject *self, PyObject *arg) {
 840         return cpy_unregister_generic_userdata(plugin_unregister_log, arg, "log");
 841 }
 842
 843 static PyObject *cpy_unregister_init(PyObject *self, PyObject *arg) {
 844         return cpy_unregister_generic(&cpy_init_callbacks, arg, "init");
 845 }
 846
 847 static PyObject *cpy_unregister_config(PyObject *self, PyObject *arg) {
 848         return cpy_unregister_generic(&cpy_config_callbacks, arg, "config");
 849 }
 850
 851 static PyObject *cpy_unregister_read(PyObject *self, PyObject *arg) {
 852         return cpy_unregister_generic_userdata(plugin_unregister_read, arg, "read");
 853 }
 854
 855 static PyObject *cpy_unregister_write(PyObject *self, PyObject *arg) {
 856         return cpy_unregister_generic_userdata(plugin_unregister_write, arg, "write");
 857 }
 858
 859 static PyObject *cpy_unregister_notification(PyObject *self, PyObject *arg) {
 860         return cpy_unregister_generic_userdata(plugin_unregister_notification, arg, "notification");
 861 }
 862
 863 static PyObject *cpy_unregister_flush(PyObject *self, PyObject *arg) {
 864         return cpy_unregister_generic_userdata(plugin_unregister_flush, arg, "flush");
 865 }
 866
 867 static PyObject *cpy_unregister_shutdown(PyObject *self, PyObject *arg) {
 868         return cpy_unregister_generic(&cpy_shutdown_callbacks, arg, "shutdown");
 869 }
 870
 871 static PyMethodDef cpy_methods[] = {
 872         {"debug", cpy_debug, METH_VARARGS, log_doc},
 873         {"info", cpy_info, METH_VARARGS, log_doc},
 874         {"notice", cpy_notice, METH_VARARGS, log_doc},
 875         {"warning", cpy_warning, METH_VARARGS, log_doc},
 876         {"error", cpy_error, METH_VARARGS, log_doc},
 877         {"get_dataset", (PyCFunction) cpy_get_dataset, METH_VARARGS, get_ds_doc},
 878         {"flush", (PyCFunction) cpy_flush, METH_VARARGS | METH_KEYWORDS, flush_doc},
 879         {"register_log", (PyCFunction) cpy_register_log, METH_VARARGS | METH_KEYWORDS, reg_log_doc},
 880         {"register_init", (PyCFunction) cpy_register_init, METH_VARARGS | METH_KEYWORDS, reg_init_doc},
 881         {"register_config", (PyCFunction) cpy_register_config, METH_VARARGS | METH_KEYWORDS, reg_config_doc},
 882         {"register_read", (PyCFunction) cpy_register_read, METH_VARARGS | METH_KEYWORDS, reg_read_doc},
 883         {"register_write", (PyCFunction) cpy_register_write, METH_VARARGS | METH_KEYWORDS, reg_write_doc},
 884         {"register_notification", (PyCFunction) cpy_register_notification, METH_VARARGS | METH_KEYWORDS, reg_notification_doc},
 885         {"register_flush", (PyCFunction) cpy_register_flush, METH_VARARGS | METH_KEYWORDS, reg_flush_doc},
 886         {"register_shutdown", (PyCFunction) cpy_register_shutdown, METH_VARARGS | METH_KEYWORDS, reg_shutdown_doc},
 887         {"unregister_log", cpy_unregister_log, METH_O, unregister_doc},
 888         {"unregister_init", cpy_unregister_init, METH_O, unregister_doc},
 889         {"unregister_config", cpy_unregister_config, METH_O, unregister_doc},
 890         {"unregister_read", cpy_unregister_read, METH_O, unregister_doc},
 891         {"unregister_write", cpy_unregister_write, METH_O, unregister_doc},
 892         {"unregister_notification", cpy_unregister_notification, METH_O, unregister_doc},
 893         {"unregister_flush", cpy_unregister_flush, METH_O, unregister_doc},
 894         {"unregister_shutdown", cpy_unregister_shutdown, METH_O, unregister_doc},
 895         {0, 0, 0, 0}
 896 };
 897
 898 static int cpy_shutdown(void) {
 899         PyObject *ret;
 900
 901         /* This can happen if the module was loaded but not configured. */
 902         if (state != NULL)
 903                 PyEval_RestoreThread(state);
 904
 905         for (cpy_callback_t *c = cpy_shutdown_callbacks; c; c = c->next) {
 906                 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
 907                 if (ret == NULL)
 908                         cpy_log_exception("shutdown callback");
 909                 else
 910                         Py_DECREF(ret);
 911         }
 912         PyErr_Print();
 913         Py_Finalize();
 914         return 0;
 915 }
 916
 917 static void *cpy_interactive(void *data) {
 918         PyOS_sighandler_t cur_sig;
 919
 920         /* Signal handler in a plugin? Bad stuff, but the best way to
 921          * handle it I guess. In an interactive session people will
 922          * press Ctrl+C at some time, which will generate a SIGINT.
 923          * This will cause collectd to shutdown, thus killing the
 924          * interactive interpreter, and leaving the terminal in a
 925          * mess. Chances are, this isn't what the user wanted to do.
 926          *
 927          * So this is the plan:
 928          * 1. Restore Python's own signal handler
 929          * 2. Tell Python we just forked so it will accept this thread
 930          *    as the main one. No version of Python will ever handle
 931          *    interrupts anywhere but in the main thread.
 932          * 3. After the interactive loop is done, restore collectd's
 933          *    SIGINT handler.
 934          * 4. Raise SIGINT for a clean shutdown. The signal is sent to
 935          *    the main thread to ensure it wakes up the main interval
 936          *    sleep so that collectd shuts down immediately not in 10
 937          *    seconds.
 938          *
 939          * This will make sure that SIGINT won't kill collectd but
 940          * still interrupt syscalls like sleep and pause. */
 941
 942         PyEval_AcquireThread(state);
 943         if (PyImport_ImportModule("readline") == NULL) {
 944                 /* This interactive session will suck. */
 945                 cpy_log_exception("interactive session init");
 946         }
 947         cur_sig = PyOS_setsig(SIGINT, python_sigint_handler);
 948         /* We totally forked just now. Everyone saw that, right? */
 949         PyOS_AfterFork();
 950         PyRun_InteractiveLoop(stdin, "<stdin>");
 951         PyOS_setsig(SIGINT, cur_sig);
 952         PyErr_Print();
 953         PyEval_ReleaseThread(state);
 954         NOTICE("python: Interactive interpreter exited, stopping collectd ...");
 955         pthread_kill(main_thread, SIGINT);
 956         return NULL;
 957 }
 958
 959 static int cpy_init(void) {
 960         PyObject *ret;
 961         static pthread_t thread;
 962
 963         if (!Py_IsInitialized()) {
 964                 WARNING("python: Plugin loaded but not configured.");
 965                 plugin_unregister_shutdown("python");
 966                 return 0;
 967         }
 968         PyEval_InitThreads();
 969         /* Now it's finally OK to use python threads. */
 970         for (cpy_callback_t *c = cpy_init_callbacks; c; c = c->next) {
 971                 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
 972                 if (ret == NULL)
 973                         cpy_log_exception("init callback");
 974                 else
 975                         Py_DECREF(ret);
 976         }
 977         state = PyEval_SaveThread();
 978         main_thread = pthread_self();
 979         if (do_interactive) {
 980                 if (plugin_thread_create(&thread, NULL, cpy_interactive, NULL)) {
 981                         ERROR("python: Error creating thread for interactive interpreter.");
 982                 }
 983         }
 984
 985         return 0;
 986 }
 987
 988 static PyObject *cpy_oconfig_to_pyconfig(oconfig_item_t *ci, PyObject *parent) {
 989         PyObject *item, *values, *children, *tmp;
 990
 991         if (parent == NULL)
 992                 parent = Py_None;
 993
 994         values = PyTuple_New(ci->values_num); /* New reference. */
 995         for (int i = 0; i < ci->values_num; ++i) {
 996                 if (ci->values[i].type == OCONFIG_TYPE_STRING) {
 997                         PyTuple_SET_ITEM(values, i, cpy_string_to_unicode_or_bytes(ci->values[i].value.string));
 998                 } else if (ci->values[i].type == OCONFIG_TYPE_NUMBER) {
 999                         PyTuple_SET_ITEM(values, i, PyFloat_FromDouble(ci->values[i].value.number));
1000                 } else if (ci->values[i].type == OCONFIG_TYPE_BOOLEAN) {
1001                         PyTuple_SET_ITEM(values, i, PyBool_FromLong(ci->values[i].value.boolean));
1002                 }
1003         }
1004
1005         tmp = cpy_string_to_unicode_or_bytes(ci->key);
1006         item = PyObject_CallFunction((void *) &ConfigType, "NONO", tmp, parent, values, Py_None);
1007         if (item == NULL)
1008                 return NULL;
1009         children = PyTuple_New(ci->children_num); /* New reference. */
1010         for (int i = 0; i < ci->children_num; ++i) {
1011                 PyTuple_SET_ITEM(children, i, cpy_oconfig_to_pyconfig(ci->children + i, item));
1012         }
1013         tmp = ((Config *) item)->children;
1014         ((Config *) item)->children = children;
1015         Py_XDECREF(tmp);
1016         return item;
1017 }
1018
1019 #ifdef IS_PY3K
1020 static struct PyModuleDef collectdmodule = {
1021         PyModuleDef_HEAD_INIT,
1022         "collectd",   /* name of module */
1023         "The python interface to collectd", /* module documentation, may be NULL */
1024         -1,
1025         cpy_methods
1026 };
1027
1028 PyMODINIT_FUNC PyInit_collectd(void) {
1029         return PyModule_Create(&collectdmodule);
1030 }
1031 #endif
1032
1033 static int cpy_init_python(void) {
1034         PyOS_sighandler_t cur_sig;
1035         PyObject *sys;
1036         PyObject *module;
1037
1038 #ifdef IS_PY3K
1039         wchar_t *argv = L"";
1040         /* Add a builtin module, before Py_Initialize */
1041         PyImport_AppendInittab("collectd", PyInit_collectd);
1042 #else
1043         char *argv = "";
1044 #endif
1045
1046         /* Chances are the current signal handler is already SIG_DFL, but let's make sure. */
1047         cur_sig = PyOS_setsig(SIGINT, SIG_DFL);
1048         Py_Initialize();
1049         python_sigint_handler = PyOS_setsig(SIGINT, cur_sig);
1050
1051         PyType_Ready(&ConfigType);
1052         PyType_Ready(&PluginDataType);
1053         ValuesType.tp_base = &PluginDataType;
1054         PyType_Ready(&ValuesType);
1055         NotificationType.tp_base = &PluginDataType;
1056         PyType_Ready(&NotificationType);
1057         SignedType.tp_base = &PyLong_Type;
1058         PyType_Ready(&SignedType);
1059         UnsignedType.tp_base = &PyLong_Type;
1060         PyType_Ready(&UnsignedType);
1061         sys = PyImport_ImportModule("sys"); /* New reference. */
1062         if (sys == NULL) {
1063                 cpy_log_exception("python initialization");
1064                 return 1;
1065         }
1066         sys_path = PyObject_GetAttrString(sys, "path"); /* New reference. */
1067         Py_DECREF(sys);
1068         if (sys_path == NULL) {
1069                 cpy_log_exception("python initialization");
1070                 return 1;
1071         }
1072         PySys_SetArgv(1, &argv);
1073         PyList_SetSlice(sys_path, 0, 1, NULL);
1074
1075 #ifdef IS_PY3K
1076         module = PyImport_ImportModule("collectd");
1077 #else
1078         module = Py_InitModule("collectd", cpy_methods); /* Borrowed reference. */
1079 #endif
1080         PyModule_AddObject(module, "Config", (void *) &ConfigType); /* Steals a reference. */
1081         PyModule_AddObject(module, "Values", (void *) &ValuesType); /* Steals a reference. */
1082         PyModule_AddObject(module, "Notification", (void *) &NotificationType); /* Steals a reference. */
1083         PyModule_AddObject(module, "Signed", (void *) &SignedType); /* Steals a reference. */
1084         PyModule_AddObject(module, "Unsigned", (void *) &UnsignedType); /* Steals a reference. */
1085         PyModule_AddIntConstant(module, "LOG_DEBUG", LOG_DEBUG);
1086         PyModule_AddIntConstant(module, "LOG_INFO", LOG_INFO);
1087         PyModule_AddIntConstant(module, "LOG_NOTICE", LOG_NOTICE);
1088         PyModule_AddIntConstant(module, "LOG_WARNING", LOG_WARNING);
1089         PyModule_AddIntConstant(module, "LOG_ERROR", LOG_ERR);
1090         PyModule_AddIntConstant(module, "NOTIF_FAILURE", NOTIF_FAILURE);
1091         PyModule_AddIntConstant(module, "NOTIF_WARNING", NOTIF_WARNING);
1092         PyModule_AddIntConstant(module, "NOTIF_OKAY", NOTIF_OKAY);
1093         PyModule_AddStringConstant(module, "DS_TYPE_COUNTER", DS_TYPE_TO_STRING(DS_TYPE_COUNTER));
1094         PyModule_AddStringConstant(module, "DS_TYPE_GAUGE", DS_TYPE_TO_STRING(DS_TYPE_GAUGE));
1095         PyModule_AddStringConstant(module, "DS_TYPE_DERIVE", DS_TYPE_TO_STRING(DS_TYPE_DERIVE));
1096         PyModule_AddStringConstant(module, "DS_TYPE_ABSOLUTE", DS_TYPE_TO_STRING(DS_TYPE_ABSOLUTE));
1097         return 0;
1098 }
1099
1100 static int cpy_config(oconfig_item_t *ci) {
1101         PyObject *tb;
1102         int status = 0;
1103
1104         /* Ok in theory we shouldn't do initialization at this point
1105          * but we have to. In order to give python scripts a chance
1106          * to register a config callback we need to be able to execute
1107          * python code during the config callback so we have to start
1108          * the interpreter here. */
1109         /* Do *not* use the python "thread" module at this point! */
1110
1111         if (!Py_IsInitialized() && cpy_init_python()) return 1;
1112
1113         for (int i = 0; i < ci->children_num; ++i) {
1114                 oconfig_item_t *item = ci->children + i;
1115
1116                 if (strcasecmp(item->key, "Interactive") == 0) {
1117                         if (cf_util_get_boolean(item, &do_interactive) != 0) {
1118                                 status = 1;
1119                                 continue;
1120                         }
1121                 } else if (strcasecmp(item->key, "Encoding") == 0) {
1122                         char *encoding = NULL;
1123                         if (cf_util_get_string(item, &encoding) != 0) {
1124                                 status = 1;
1125                                 continue;
1126                         }
1127 #ifdef IS_PY3K
1128                         ERROR("python: \"Encoding\" was used in the config file but Python3 was used, which does not support changing encodings");
1129                         status = 1;
1130                         sfree(encoding);
1131                         continue;
1132 #else
1133                         /* Why is this even necessary? And undocumented? */
1134                         if (PyUnicode_SetDefaultEncoding(encoding)) {
1135                                 cpy_log_exception("setting default encoding");
1136                                 status = 1;
1137                         }
1138 #endif
1139                         sfree(encoding);
1140                 } else if (strcasecmp(item->key, "LogTraces") == 0) {
1141                         _Bool log_traces;
1142                         if (cf_util_get_boolean(item, &log_traces) != 0) {
1143                                 status = 1;
1144                                 continue;
1145                         }
1146                         if (!log_traces) {
1147                                 Py_XDECREF(cpy_format_exception);
1148                                 cpy_format_exception = NULL;
1149                                 continue;
1150                         }
1151                         if (cpy_format_exception)
1152                                 continue;
1153                         tb = PyImport_ImportModule("traceback"); /* New reference. */
1154                         if (tb == NULL) {
1155                                 cpy_log_exception("python initialization");
1156                                 status = 1;
1157                                 continue;
1158                         }
1159                         cpy_format_exception = PyObject_GetAttrString(tb, "format_exception"); /* New reference. */
1160                         Py_DECREF(tb);
1161                         if (cpy_format_exception == NULL) {
1162                                 cpy_log_exception("python initialization");
1163                                 status = 1;
1164                         }
1165                 } else if (strcasecmp(item->key, "ModulePath") == 0) {
1166                         char *dir = NULL;
1167                         PyObject *dir_object;
1168
1169                         if (cf_util_get_string(item, &dir) != 0) {
1170                                 status = 1;
1171                                 continue;
1172                         }
1173                         dir_object = cpy_string_to_unicode_or_bytes(dir); /* New reference. */
1174                         if (dir_object == NULL) {
1175                                 ERROR("python plugin: Unable to convert \"%s\" to "
1176                                       "a python object.", dir);
1177                                 free(dir);
1178                                 cpy_log_exception("python initialization");
1179                                 status = 1;
1180                                 continue;
1181                         }
1182                         if (PyList_Insert(sys_path, 0, dir_object) != 0) {
1183                                 ERROR("python plugin: Unable to prepend \"%s\" to "
1184                                       "python module path.", dir);
1185                                 cpy_log_exception("python initialization");
1186                                 status = 1;
1187                         }
1188                         Py_DECREF(dir_object);
1189                         free(dir);
1190                 } else if (strcasecmp(item->key, "Import") == 0) {
1191                         char *module_name = NULL;
1192                         PyObject *module;
1193
1194                         if (cf_util_get_string(item, &module_name) != 0) {
1195                                 status = 1;
1196                                 continue;
1197                         }
1198                         module = PyImport_ImportModule(module_name); /* New reference. */
1199                         if (module == NULL) {
1200                                 ERROR("python plugin: Error importing module \"%s\".", module_name);
1201                                 cpy_log_exception("importing module");
1202                                 status = 1;
1203                         }
1204                         free(module_name);
1205                         Py_XDECREF(module);
1206                 } else if (strcasecmp(item->key, "Module") == 0) {
1207                         char *name = NULL;
1208                         cpy_callback_t *c;
1209                         PyObject *ret;
1210
1211                         if (cf_util_get_string(item, &name) != 0) {
1212                                 status = 1;
1213                                 continue;
1214                         }
1215                         for (c = cpy_config_callbacks; c; c = c->next) {
1216                                 if (strcasecmp(c->name + 7, name) == 0)
1217                                         break;
1218                         }
1219                         if (c == NULL) {
1220                                 WARNING("python plugin: Found a configuration for the \"%s\" plugin, "
1221                                         "but the plugin isn't loaded or didn't register "
1222                                         "a configuration callback.", name);
1223                                 free(name);
1224                                 continue;
1225                         }
1226                         free(name);
1227                         if (c->data == NULL)
1228                                 ret = PyObject_CallFunction(c->callback, "N",
1229                                         cpy_oconfig_to_pyconfig(item, NULL)); /* New reference. */
1230                         else
1231                                 ret = PyObject_CallFunction(c->callback, "NO",
1232                                         cpy_oconfig_to_pyconfig(item, NULL), c->data); /* New reference. */
1233                         if (ret == NULL) {
1234                                 cpy_log_exception("loading module");
1235                                 status = 1;
1236                         } else
1237                                 Py_DECREF(ret);
1238                 } else {
1239                         ERROR("python plugin: Unknown config key \"%s\".", item->key);
1240                         status = 1;
1241                 }
1242         }
1243         return (status);
1244 }
1245
1246 void module_register(void) {
1247         plugin_register_complex_config("python", cpy_config);
1248         plugin_register_init("python", cpy_init);
1249         plugin_register_shutdown("python", cpy_shutdown);
1250 }