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 #if HAVE_PTHREAD_H
  32 # include <pthread.h>
  33 #endif
  34
  35 #include "collectd.h"
  36 #include "common.h"
  37
  38 #include "cpython.h"
  39
  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;
  46
  47 static char log_doc[] = "This function sends a string to all logging plugins.";
  48
  49 static char flush_doc[] = "flush([plugin][, timeout][, identifier]) -> None\n"
  50                 "\n"
  51                 "Flushes the cache of another plugin.";
  52
  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.";
  55
  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.";
  76
  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.";
  95
  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.";
 113
 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.";
 133
 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.";
 152
 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.";
 171
 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.";
 192
 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.";
 209
 210
 211 static int do_interactive = 0;
 212
 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. */
 217
 218 static PyThreadState *state;
 219
 220 static PyObject *cpy_format_exception;
 221
 222 static cpy_callback_t *cpy_config_callbacks;
 223 static cpy_callback_t *cpy_init_callbacks;
 224 static cpy_callback_t *cpy_shutdown_callbacks;
 225
 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 }
 233
 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. */
 236
 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;
 240
 241         if (name != NULL) {
 242                 snprintf(buf, size, "python.%s", name);
 243                 return;
 244         }
 245
 246         mod = PyObject_GetAttrString(callback, "__module__"); /* New reference. */
 247         if (mod != NULL)
 248                 module = cpy_unicode_or_bytes_to_string(&mod);
 249
 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);
 257
 258         snprintf(buf, size, "python.%p", callback);
 259         PyErr_Clear();
 260 }
 261
 262 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;
 266
 267         PyErr_Fetch(&type, &value, &traceback);
 268         PyErr_NormalizeException(&type, &value, &traceback);
 269         if (type == NULL) return;
 270         tn = PyObject_GetAttrString(type, "__name__"); /* New reference. */
 271         m = PyObject_Str(value); /* New reference. */
 272         if (tn != NULL)
 273                 typename = cpy_unicode_or_bytes_to_string(&tn);
 274         if (m != NULL)
 275                 message = cpy_unicode_or_bytes_to_string(&m);
 276         if (typename == NULL)
 277                 typename = "NamelessException";
 278         if (message == NULL)
 279                 message = "N/A";
 280         Py_BEGIN_ALLOW_THREADS
 281         ERROR("Unhandled python exception in %s: %s: %s", context, typename, message);
 282         Py_END_ALLOW_THREADS
 283         Py_XDECREF(tn);
 284         Py_XDECREF(m);
 285         if (!cpy_format_exception) {
 286                 PyErr_Clear();
 287                 Py_XDECREF(type);
 288                 Py_XDECREF(value);
 289                 Py_XDECREF(traceback);
 290                 return;
 291         }
 292         if (!traceback) {
 293                 PyErr_Clear();
 294                 return;
 295         }
 296         list = PyObject_CallFunction(cpy_format_exception, "NNN", type, value, traceback); /* New reference. */
 297         if (list)
 298                 l = PyObject_Length(list);
 299         for (i = 0; i < l; ++i) {
 300                 char *s;
 301                 PyObject *line;
 302
 303                 line = PyList_GET_ITEM(list, i); /* Borrowed reference. */
 304                 Py_INCREF(line);
 305                 s = strdup(cpy_unicode_or_bytes_to_string(&line));
 306                 Py_DECREF(line);
 307                 if (s[strlen(s) - 1] == '\n')
 308                         s[strlen(s) - 1] = 0;
 309                 Py_BEGIN_ALLOW_THREADS
 310                 ERROR("%s", s);
 311                 Py_END_ALLOW_THREADS
 312                 free(s);
 313         }
 314         Py_XDECREF(list);
 315         PyErr_Clear();
 316 }
 317
 318 static int cpy_read_callback(user_data_t *data) {
 319         cpy_callback_t *c = data->data;
 320         PyObject *ret;
 321
 322         CPY_LOCK_THREADS
 323                 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
 324                 if (ret == NULL) {
 325                         cpy_log_exception("read callback");
 326                 } else {
 327                         Py_DECREF(ret);
 328                 }
 329         CPY_RELEASE_THREADS
 330         if (ret == NULL)
 331                 return 1;
 332         return 0;
 333 }
 334
 335 static int cpy_write_callback(const data_set_t *ds, const value_list_t *value_list, user_data_t *data) {
 336         int i;
 337         cpy_callback_t *c = data->data;
 338         PyObject *ret, *list, *temp, *dict = NULL;
 339         Values *v;
 340
 341         CPY_LOCK_THREADS
 342                 list = PyList_New(value_list->values_len); /* New reference. */
 343                 if (list == NULL) {
 344                         cpy_log_exception("write callback");
 345                         CPY_RETURN_FROM_THREADS 0;
 346                 }
 347                 for (i = 0; i < value_list->values_len; ++i) {
 348                         if (ds->ds->type == DS_TYPE_COUNTER) {
 349                                 if ((long) value_list->values[i].counter == value_list->values[i].counter)
 350                                         PyList_SetItem(list, i, PyInt_FromLong(value_list->values[i].counter));
 351                                 else
 352                                         PyList_SetItem(list, i, PyLong_FromUnsignedLongLong(value_list->values[i].counter));
 353                         } else if (ds->ds->type == DS_TYPE_GAUGE) {
 354                                 PyList_SetItem(list, i, PyFloat_FromDouble(value_list->values[i].gauge));
 355                         } else if (ds->ds->type == DS_TYPE_DERIVE) {
 356                                 if ((long) value_list->values[i].derive == value_list->values[i].derive)
 357                                         PyList_SetItem(list, i, PyInt_FromLong(value_list->values[i].derive));
 358                                 else
 359                                         PyList_SetItem(list, i, PyLong_FromLongLong(value_list->values[i].derive));
 360                         } else if (ds->ds->type == DS_TYPE_ABSOLUTE) {
 361                                 if ((long) value_list->values[i].absolute == value_list->values[i].absolute)
 362                                         PyList_SetItem(list, i, PyInt_FromLong(value_list->values[i].absolute));
 363                                 else
 364                                         PyList_SetItem(list, i, PyLong_FromUnsignedLongLong(value_list->values[i].absolute));
 365                         } else {
 366                                 Py_BEGIN_ALLOW_THREADS
 367                                 ERROR("cpy_write_callback: Unknown value type %d.", ds->ds->type);
 368                                 Py_END_ALLOW_THREADS
 369                                 Py_DECREF(list);
 370                                 CPY_RETURN_FROM_THREADS 0;
 371                         }
 372                         if (PyErr_Occurred() != NULL) {
 373                                 cpy_log_exception("value building for write callback");
 374                                 Py_DECREF(list);
 375                                 CPY_RETURN_FROM_THREADS 0;
 376                         }
 377                 }
 378                 dict = PyDict_New();
 379                 if (value_list->meta) {
 380                         int i, num;
 381                         char **table;
 382                         meta_data_t *meta = value_list->meta;
 383
 384                         num = meta_data_toc(meta, &table);
 385                         for (i = 0; i < num; ++i) {
 386                                 int type;
 387                                 char *string;
 388                                 int64_t si;
 389                                 uint64_t ui;
 390                                 double d;
 391                                 _Bool b;
 392
 393                                 type = meta_data_type(meta, table[i]);
 394                                 if (type == MD_TYPE_STRING) {
 395                                         if (meta_data_get_string(meta, table[i], &string))
 396                                                 continue;
 397                                         temp = cpy_string_to_unicode_or_bytes(string);
 398                                         free(string);
 399                                         PyDict_SetItemString(dict, table[i], temp);
 400                                         Py_XDECREF(temp);
 401                                 } else if (type == MD_TYPE_SIGNED_INT) {
 402                                         if (meta_data_get_signed_int(meta, table[i], &si))
 403                                                 continue;
 404                                         temp = PyObject_CallFunctionObjArgs((void *) &SignedType, PyLong_FromLongLong(si), (void *) 0);
 405                                         PyDict_SetItemString(dict, table[i], temp);
 406                                         Py_XDECREF(temp);
 407                                 } else if (type == MD_TYPE_UNSIGNED_INT) {
 408                                         if (meta_data_get_unsigned_int(meta, table[i], &ui))
 409                                                 continue;
 410                                         temp = PyObject_CallFunctionObjArgs((void *) &UnsignedType, PyLong_FromUnsignedLongLong(ui), (void *) 0);
 411                                         PyDict_SetItemString(dict, table[i], temp);
 412                                         Py_XDECREF(temp);
 413                                 } else if (type == MD_TYPE_DOUBLE) {
 414                                         if (meta_data_get_double(meta, table[i], &d))
 415                                                 continue;
 416                                         temp = PyFloat_FromDouble(d);
 417                                         PyDict_SetItemString(dict, table[i], temp);
 418                                         Py_XDECREF(temp);
 419                                 } else if (type == MD_TYPE_BOOLEAN) {
 420                                         if (meta_data_get_boolean(meta, table[i], &b))
 421                                                 continue;
 422                                         if (b)
 423                                                 PyDict_SetItemString(dict, table[i], Py_True);
 424                                         else
 425                                                 PyDict_SetItemString(dict, table[i], Py_False);
 426                                 }
 427                                 free(table[i]);
 428                         }
 429                         free(table);
 430                 }
 431                 v = PyObject_New(Values, (void *) &ValuesType); /* New reference. */
 432                 sstrncpy(v->data.host, value_list->host, sizeof(v->data.host));
 433                 sstrncpy(v->data.type, value_list->type, sizeof(v->data.type));
 434                 sstrncpy(v->data.type_instance, value_list->type_instance, sizeof(v->data.type_instance));
 435                 sstrncpy(v->data.plugin, value_list->plugin, sizeof(v->data.plugin));
 436                 sstrncpy(v->data.plugin_instance, value_list->plugin_instance, sizeof(v->data.plugin_instance));
 437                 v->data.time = value_list->time;
 438                 v->interval = value_list->interval;
 439                 v->values = list;
 440                 v->meta = dict;
 441                 ret = PyObject_CallFunctionObjArgs(c->callback, v, c->data, (void *) 0); /* New reference. */
 442                 Py_XDECREF(v);
 443                 if (ret == NULL) {
 444                         cpy_log_exception("write callback");
 445                 } else {
 446                         Py_DECREF(ret);
 447                 }
 448         CPY_RELEASE_THREADS
 449         return 0;
 450 }
 451
 452 static int cpy_notification_callback(const notification_t *notification, user_data_t *data) {
 453         cpy_callback_t *c = data->data;
 454         PyObject *ret;
 455         Notification *n;
 456
 457         CPY_LOCK_THREADS
 458                 n = PyObject_New(Notification, (void *) &NotificationType); /* New reference. */
 459                 sstrncpy(n->data.host, notification->host, sizeof(n->data.host));
 460                 sstrncpy(n->data.type, notification->type, sizeof(n->data.type));
 461                 sstrncpy(n->data.type_instance, notification->type_instance, sizeof(n->data.type_instance));
 462                 sstrncpy(n->data.plugin, notification->plugin, sizeof(n->data.plugin));
 463                 sstrncpy(n->data.plugin_instance, notification->plugin_instance, sizeof(n->data.plugin_instance));
 464                 n->data.time = notification->time;
 465                 sstrncpy(n->message, notification->message, sizeof(n->message));
 466                 n->severity = notification->severity;
 467                 ret = PyObject_CallFunctionObjArgs(c->callback, n, c->data, (void *) 0); /* New reference. */
 468                 Py_XDECREF(n);
 469                 if (ret == NULL) {
 470                         cpy_log_exception("notification callback");
 471                 } else {
 472                         Py_DECREF(ret);
 473                 }
 474         CPY_RELEASE_THREADS
 475         return 0;
 476 }
 477
 478 static void cpy_log_callback(int severity, const char *message, user_data_t *data) {
 479         cpy_callback_t * c = data->data;
 480         PyObject *ret, *text;
 481
 482         CPY_LOCK_THREADS
 483         text = cpy_string_to_unicode_or_bytes(message);
 484         if (c->data == NULL)
 485                 ret = PyObject_CallFunction(c->callback, "iN", severity, text); /* New reference. */
 486         else
 487                 ret = PyObject_CallFunction(c->callback, "iNO", severity, text, c->data); /* New reference. */
 488
 489         if (ret == NULL) {
 490                 /* FIXME */
 491                 /* Do we really want to trigger a log callback because a log callback failed?
 492                  * Probably not. */
 493                 PyErr_Print();
 494                 /* In case someone wanted to be clever, replaced stderr and failed at that. */
 495                 PyErr_Clear();
 496         } else {
 497                 Py_DECREF(ret);
 498         }
 499         CPY_RELEASE_THREADS
 500 }
 501
 502 static void cpy_flush_callback(int timeout, const char *id, user_data_t *data) {
 503         cpy_callback_t * c = data->data;
 504         PyObject *ret, *text;
 505
 506         CPY_LOCK_THREADS
 507         text = cpy_string_to_unicode_or_bytes(id);
 508         if (c->data == NULL)
 509                 ret = PyObject_CallFunction(c->callback, "iN", timeout, text); /* New reference. */
 510         else
 511                 ret = PyObject_CallFunction(c->callback, "iNO", timeout, text, c->data); /* New reference. */
 512
 513         if (ret == NULL) {
 514                 cpy_log_exception("flush callback");
 515         } else {
 516                 Py_DECREF(ret);
 517         }
 518         CPY_RELEASE_THREADS
 519 }
 520
 521 static PyObject *cpy_register_generic(cpy_callback_t **list_head, PyObject *args, PyObject *kwds) {
 522         char buf[512];
 523         cpy_callback_t *c;
 524         const char *name = NULL;
 525         PyObject *callback = NULL, *data = NULL, *mod = NULL;
 526         static char *kwlist[] = {"callback", "data", "name", NULL};
 527
 528         if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oet", kwlist, &callback, &data, NULL, &name) == 0) return NULL;
 529         if (PyCallable_Check(callback) == 0) {
 530                 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
 531                 return NULL;
 532         }
 533         cpy_build_name(buf, sizeof(buf), callback, name);
 534
 535         Py_INCREF(callback);
 536         Py_XINCREF(data);
 537         c = malloc(sizeof(*c));
 538         c->name = strdup(buf);
 539         c->callback = callback;
 540         c->data = data;
 541         c->next = *list_head;
 542         *list_head = c;
 543         Py_XDECREF(mod);
 544         return cpy_string_to_unicode_or_bytes(buf);
 545 }
 546
 547 static PyObject *cpy_flush(cpy_callback_t **list_head, PyObject *args, PyObject *kwds) {
 548         int timeout = -1;
 549         const char *plugin = NULL, *identifier = NULL;
 550         static char *kwlist[] = {"plugin", "timeout", "identifier", NULL};
 551
 552         if (PyArg_ParseTupleAndKeywords(args, kwds, "|etiet", kwlist, NULL, &plugin, &timeout, NULL, &identifier) == 0) return NULL;
 553         Py_BEGIN_ALLOW_THREADS
 554         plugin_flush(plugin, timeout, identifier);
 555         Py_END_ALLOW_THREADS
 556         Py_RETURN_NONE;
 557 }
 558
 559 static PyObject *cpy_register_config(PyObject *self, PyObject *args, PyObject *kwds) {
 560         return cpy_register_generic(&cpy_config_callbacks, args, kwds);
 561 }
 562
 563 static PyObject *cpy_register_init(PyObject *self, PyObject *args, PyObject *kwds) {
 564         return cpy_register_generic(&cpy_init_callbacks, args, kwds);
 565 }
 566
 567 typedef int reg_function_t(const char *name, void *callback, void *data);
 568
 569 static PyObject *cpy_register_generic_userdata(void *reg, void *handler, PyObject *args, PyObject *kwds) {
 570         char buf[512];
 571         reg_function_t *register_function = (reg_function_t *) reg;
 572         cpy_callback_t *c = NULL;
 573         user_data_t *user_data = NULL;
 574         const char *name = NULL;
 575         PyObject *callback = NULL, *data = NULL;
 576         static char *kwlist[] = {"callback", "data", "name", NULL};
 577
 578         if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oet", kwlist, &callback, &data, NULL, &name) == 0) return NULL;
 579         if (PyCallable_Check(callback) == 0) {
 580                 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
 581                 return NULL;
 582         }
 583         cpy_build_name(buf, sizeof(buf), callback, name);
 584
 585         Py_INCREF(callback);
 586         Py_XINCREF(data);
 587         c = malloc(sizeof(*c));
 588         c->name = strdup(buf);
 589         c->callback = callback;
 590         c->data = data;
 591         c->next = NULL;
 592         user_data = malloc(sizeof(*user_data));
 593         user_data->free_func = cpy_destroy_user_data;
 594         user_data->data = c;
 595         register_function(buf, handler, user_data);
 596         return cpy_string_to_unicode_or_bytes(buf);
 597 }
 598
 599 static PyObject *cpy_register_read(PyObject *self, PyObject *args, PyObject *kwds) {
 600         char buf[512];
 601         cpy_callback_t *c = NULL;
 602         user_data_t *user_data = NULL;
 603         double interval = 0;
 604         const char *name = NULL;
 605         PyObject *callback = NULL, *data = NULL;
 606         struct timespec ts;
 607         static char *kwlist[] = {"callback", "interval", "data", "name", NULL};
 608
 609         if (PyArg_ParseTupleAndKeywords(args, kwds, "O|dOet", kwlist, &callback, &interval, &data, NULL, &name) == 0) return NULL;
 610         if (PyCallable_Check(callback) == 0) {
 611                 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
 612                 return NULL;
 613         }
 614         cpy_build_name(buf, sizeof(buf), callback, name);
 615
 616         Py_INCREF(callback);
 617         Py_XINCREF(data);
 618         c = malloc(sizeof(*c));
 619         c->name = strdup(buf);
 620         c->callback = callback;
 621         c->data = data;
 622         c->next = NULL;
 623         user_data = malloc(sizeof(*user_data));
 624         user_data->free_func = cpy_destroy_user_data;
 625         user_data->data = c;
 626         ts.tv_sec = interval;
 627         ts.tv_nsec = (interval - ts.tv_sec) * 1000000000;
 628         plugin_register_complex_read(/* group = */ NULL, buf,
 629                         cpy_read_callback, &ts, user_data);
 630         return cpy_string_to_unicode_or_bytes(buf);
 631 }
 632
 633 static PyObject *cpy_register_log(PyObject *self, PyObject *args, PyObject *kwds) {
 634         return cpy_register_generic_userdata((void *) plugin_register_log,
 635                         (void *) cpy_log_callback, args, kwds);
 636 }
 637
 638 static PyObject *cpy_register_write(PyObject *self, PyObject *args, PyObject *kwds) {
 639         return cpy_register_generic_userdata((void *) plugin_register_write,
 640                         (void *) cpy_write_callback, args, kwds);
 641 }
 642
 643 static PyObject *cpy_register_notification(PyObject *self, PyObject *args, PyObject *kwds) {
 644         return cpy_register_generic_userdata((void *) plugin_register_notification,
 645                         (void *) cpy_notification_callback, args, kwds);
 646 }
 647
 648 static PyObject *cpy_register_flush(PyObject *self, PyObject *args, PyObject *kwds) {
 649         return cpy_register_generic_userdata((void *) plugin_register_flush,
 650                         (void *) cpy_flush_callback, args, kwds);
 651 }
 652
 653 static PyObject *cpy_register_shutdown(PyObject *self, PyObject *args, PyObject *kwds) {
 654         return cpy_register_generic(&cpy_shutdown_callbacks, args, kwds);
 655 }
 656
 657 static PyObject *cpy_error(PyObject *self, PyObject *args) {
 658         const char *text;
 659         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 660         Py_BEGIN_ALLOW_THREADS
 661         plugin_log(LOG_ERR, "%s", text);
 662         Py_END_ALLOW_THREADS
 663         Py_RETURN_NONE;
 664 }
 665
 666 static PyObject *cpy_warning(PyObject *self, PyObject *args) {
 667         const char *text;
 668         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 669         Py_BEGIN_ALLOW_THREADS
 670         plugin_log(LOG_WARNING, "%s", text);
 671         Py_END_ALLOW_THREADS
 672         Py_RETURN_NONE;
 673 }
 674
 675 static PyObject *cpy_notice(PyObject *self, PyObject *args) {
 676         const char *text;
 677         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 678         Py_BEGIN_ALLOW_THREADS
 679         plugin_log(LOG_NOTICE, "%s", text);
 680         Py_END_ALLOW_THREADS
 681         Py_RETURN_NONE;
 682 }
 683
 684 static PyObject *cpy_info(PyObject *self, PyObject *args) {
 685         const char *text;
 686         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 687         Py_BEGIN_ALLOW_THREADS
 688         plugin_log(LOG_INFO, "%s", text);
 689         Py_END_ALLOW_THREADS
 690         Py_RETURN_NONE;
 691 }
 692
 693 static PyObject *cpy_debug(PyObject *self, PyObject *args) {
 694 #ifdef COLLECT_DEBUG
 695         const char *text;
 696         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 697         Py_BEGIN_ALLOW_THREADS
 698         plugin_log(LOG_DEBUG, "%s", text);
 699         Py_END_ALLOW_THREADS
 700 #endif
 701         Py_RETURN_NONE;
 702 }
 703
 704 static PyObject *cpy_unregister_generic(cpy_callback_t **list_head, PyObject *arg, const char *desc) {
 705         char buf[512];
 706         const char *name;
 707         cpy_callback_t *prev = NULL, *tmp;
 708
 709         Py_INCREF(arg);
 710         name = cpy_unicode_or_bytes_to_string(&arg);
 711         if (name == NULL) {
 712                 PyErr_Clear();
 713                 if (!PyCallable_Check(arg)) {
 714                         PyErr_SetString(PyExc_TypeError, "This function needs a string or a callable object as its only parameter.");
 715                         Py_DECREF(arg);
 716                         return NULL;
 717                 }
 718                 cpy_build_name(buf, sizeof(buf), arg, NULL);
 719                 name = buf;
 720         }
 721         for (tmp = *list_head; tmp; prev = tmp, tmp = tmp->next)
 722                 if (strcmp(name, tmp->name) == 0)
 723                         break;
 724
 725         Py_DECREF(arg);
 726         if (tmp == NULL) {
 727                 PyErr_Format(PyExc_RuntimeError, "Unable to unregister %s callback '%s'.", desc, name);
 728                 return NULL;
 729         }
 730         /* Yes, this is actually save. To call this function the caller has to
 731          * hold the GIL. Well, save as long as there is only one GIL anyway ... */
 732         if (prev == NULL)
 733                 *list_head = tmp->next;
 734         else
 735                 prev->next = tmp->next;
 736         cpy_destroy_user_data(tmp);
 737         Py_RETURN_NONE;
 738 }
 739
 740 typedef int cpy_unregister_function_t(const char *name);
 741
 742 static PyObject *cpy_unregister_generic_userdata(cpy_unregister_function_t *unreg, PyObject *arg, const char *desc) {
 743         char buf[512];
 744         const char *name;
 745
 746         Py_INCREF(arg);
 747         name = cpy_unicode_or_bytes_to_string(&arg);
 748         if (name == NULL) {
 749                 PyErr_Clear();
 750                 if (!PyCallable_Check(arg)) {
 751                         PyErr_SetString(PyExc_TypeError, "This function needs a string or a callable object as its only parameter.");
 752                         Py_DECREF(arg);
 753                         return NULL;
 754                 }
 755                 cpy_build_name(buf, sizeof(buf), arg, NULL);
 756                 name = buf;
 757         }
 758         if (unreg(name) == 0) {
 759                 Py_DECREF(arg);
 760                 Py_RETURN_NONE;
 761         }
 762         PyErr_Format(PyExc_RuntimeError, "Unable to unregister %s callback '%s'.", desc, name);
 763         Py_DECREF(arg);
 764         return NULL;
 765 }
 766
 767 static PyObject *cpy_unregister_log(PyObject *self, PyObject *arg) {
 768         return cpy_unregister_generic_userdata(plugin_unregister_log, arg, "log");
 769 }
 770
 771 static PyObject *cpy_unregister_init(PyObject *self, PyObject *arg) {
 772         return cpy_unregister_generic(&cpy_init_callbacks, arg, "init");
 773 }
 774
 775 static PyObject *cpy_unregister_config(PyObject *self, PyObject *arg) {
 776         return cpy_unregister_generic(&cpy_config_callbacks, arg, "config");
 777 }
 778
 779 static PyObject *cpy_unregister_read(PyObject *self, PyObject *arg) {
 780         return cpy_unregister_generic_userdata(plugin_unregister_read, arg, "read");
 781 }
 782
 783 static PyObject *cpy_unregister_write(PyObject *self, PyObject *arg) {
 784         return cpy_unregister_generic_userdata(plugin_unregister_write, arg, "write");
 785 }
 786
 787 static PyObject *cpy_unregister_notification(PyObject *self, PyObject *arg) {
 788         return cpy_unregister_generic_userdata(plugin_unregister_notification, arg, "notification");
 789 }
 790
 791 static PyObject *cpy_unregister_flush(PyObject *self, PyObject *arg) {
 792         return cpy_unregister_generic_userdata(plugin_unregister_flush, arg, "flush");
 793 }
 794
 795 static PyObject *cpy_unregister_shutdown(PyObject *self, PyObject *arg) {
 796         return cpy_unregister_generic(&cpy_shutdown_callbacks, arg, "shutdown");
 797 }
 798
 799 static PyMethodDef cpy_methods[] = {
 800         {"debug", cpy_debug, METH_VARARGS, log_doc},
 801         {"info", cpy_info, METH_VARARGS, log_doc},
 802         {"notice", cpy_notice, METH_VARARGS, log_doc},
 803         {"warning", cpy_warning, METH_VARARGS, log_doc},
 804         {"error", cpy_error, METH_VARARGS, log_doc},
 805         {"flush", (PyCFunction) cpy_flush, METH_VARARGS | METH_KEYWORDS, flush_doc},
 806         {"register_log", (PyCFunction) cpy_register_log, METH_VARARGS | METH_KEYWORDS, reg_log_doc},
 807         {"register_init", (PyCFunction) cpy_register_init, METH_VARARGS | METH_KEYWORDS, reg_init_doc},
 808         {"register_config", (PyCFunction) cpy_register_config, METH_VARARGS | METH_KEYWORDS, reg_config_doc},
 809         {"register_read", (PyCFunction) cpy_register_read, METH_VARARGS | METH_KEYWORDS, reg_read_doc},
 810         {"register_write", (PyCFunction) cpy_register_write, METH_VARARGS | METH_KEYWORDS, reg_write_doc},
 811         {"register_notification", (PyCFunction) cpy_register_notification, METH_VARARGS | METH_KEYWORDS, reg_notification_doc},
 812         {"register_flush", (PyCFunction) cpy_register_flush, METH_VARARGS | METH_KEYWORDS, reg_flush_doc},
 813         {"register_shutdown", (PyCFunction) cpy_register_shutdown, METH_VARARGS | METH_KEYWORDS, reg_shutdown_doc},
 814         {"unregister_log", cpy_unregister_log, METH_O, unregister_doc},
 815         {"unregister_init", cpy_unregister_init, METH_O, unregister_doc},
 816         {"unregister_config", cpy_unregister_config, METH_O, unregister_doc},
 817         {"unregister_read", cpy_unregister_read, METH_O, unregister_doc},
 818         {"unregister_write", cpy_unregister_write, METH_O, unregister_doc},
 819         {"unregister_notification", cpy_unregister_notification, METH_O, unregister_doc},
 820         {"unregister_flush", cpy_unregister_flush, METH_O, unregister_doc},
 821         {"unregister_shutdown", cpy_unregister_shutdown, METH_O, unregister_doc},
 822         {0, 0, 0, 0}
 823 };
 824
 825 static int cpy_shutdown(void) {
 826         cpy_callback_t *c;
 827         PyObject *ret;
 828
 829         /* This can happen if the module was loaded but not configured. */
 830         if (state != NULL)
 831                 PyEval_RestoreThread(state);
 832
 833         for (c = cpy_shutdown_callbacks; c; c = c->next) {
 834                 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
 835                 if (ret == NULL)
 836                         cpy_log_exception("shutdown callback");
 837                 else
 838                         Py_DECREF(ret);
 839         }
 840         PyErr_Print();
 841         Py_Finalize();
 842         return 0;
 843 }
 844
 845 static void cpy_int_handler(int sig) {
 846         return;
 847 }
 848
 849 static void *cpy_interactive(void *data) {
 850         sigset_t sigset;
 851         struct sigaction sig_int_action, old;
 852
 853         /* Signal handler in a plugin? Bad stuff, but the best way to
 854          * handle it I guess. In an interactive session people will
 855          * press Ctrl+C at some time, which will generate a SIGINT.
 856          * This will cause collectd to shutdown, thus killing the
 857          * interactive interpreter, and leaving the terminal in a
 858          * mess. Chances are, this isn't what the user wanted to do.
 859          *
 860          * So this is the plan:
 861          * 1. Block SIGINT in the main thread.
 862          * 2. Install our own signal handler that does nothing.
 863          * 3. Unblock SIGINT in the interactive thread.
 864          *
 865          * This will make sure that SIGINT won't kill collectd but
 866          * still interrupt syscalls like sleep and pause.
 867          * It does not raise a KeyboardInterrupt exception because so
 868          * far nobody managed to figure out how to do that. */
 869         memset (&sig_int_action, '\0', sizeof (sig_int_action));
 870         sig_int_action.sa_handler = cpy_int_handler;
 871         sigaction (SIGINT, &sig_int_action, &old);
 872
 873         sigemptyset(&sigset);
 874         sigaddset(&sigset, SIGINT);
 875         pthread_sigmask(SIG_UNBLOCK, &sigset, NULL);
 876         PyEval_AcquireThread(state);
 877         if (PyImport_ImportModule("readline") == NULL) {
 878                 /* This interactive session will suck. */
 879                 cpy_log_exception("interactive session init");
 880         }
 881         PyRun_InteractiveLoop(stdin, "<stdin>");
 882         PyErr_Print();
 883         PyEval_ReleaseThread(state);
 884         NOTICE("python: Interactive interpreter exited, stopping collectd ...");
 885         /* Restore the original collectd SIGINT handler and raise SIGINT.
 886          * The main thread still has SIGINT blocked and there's nothing we
 887          * can do about that so this thread will handle it. But that's not
 888          * important, except that it won't interrupt the main loop and so
 889          * it might take a few seconds before collectd really shuts down. */
 890         sigaction (SIGINT, &old, NULL);
 891         raise(SIGINT);
 892         pause();
 893         return NULL;
 894 }
 895
 896 static int cpy_init(void) {
 897         cpy_callback_t *c;
 898         PyObject *ret;
 899         static pthread_t thread;
 900         sigset_t sigset;
 901
 902         if (!Py_IsInitialized()) {
 903                 WARNING("python: Plugin loaded but not configured.");
 904                 plugin_unregister_shutdown("python");
 905                 return 0;
 906         }
 907         PyEval_InitThreads();
 908         /* Now it's finally OK to use python threads. */
 909         for (c = cpy_init_callbacks; c; c = c->next) {
 910                 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
 911                 if (ret == NULL)
 912                         cpy_log_exception("init callback");
 913                 else
 914                         Py_DECREF(ret);
 915         }
 916         sigemptyset(&sigset);
 917         sigaddset(&sigset, SIGINT);
 918         pthread_sigmask(SIG_BLOCK, &sigset, NULL);
 919         state = PyEval_SaveThread();
 920         if (do_interactive) {
 921                 if (pthread_create(&thread, NULL, cpy_interactive, NULL)) {
 922                         ERROR("python: Error creating thread for interactive interpreter.");
 923                 }
 924         }
 925
 926         return 0;
 927 }
 928
 929 static PyObject *cpy_oconfig_to_pyconfig(oconfig_item_t *ci, PyObject *parent) {
 930         int i;
 931         PyObject *item, *values, *children, *tmp;
 932
 933         if (parent == NULL)
 934                 parent = Py_None;
 935
 936         values = PyTuple_New(ci->values_num); /* New reference. */
 937         for (i = 0; i < ci->values_num; ++i) {
 938                 if (ci->values[i].type == OCONFIG_TYPE_STRING) {
 939                         PyTuple_SET_ITEM(values, i, cpy_string_to_unicode_or_bytes(ci->values[i].value.string));
 940                 } else if (ci->values[i].type == OCONFIG_TYPE_NUMBER) {
 941                         PyTuple_SET_ITEM(values, i, PyFloat_FromDouble(ci->values[i].value.number));
 942                 } else if (ci->values[i].type == OCONFIG_TYPE_BOOLEAN) {
 943                         PyTuple_SET_ITEM(values, i, PyBool_FromLong(ci->values[i].value.boolean));
 944                 }
 945         }
 946
 947         tmp = cpy_string_to_unicode_or_bytes(ci->key);
 948         item = PyObject_CallFunction((void *) &ConfigType, "NONO", tmp, parent, values, Py_None);
 949         if (item == NULL)
 950                 return NULL;
 951         children = PyTuple_New(ci->children_num); /* New reference. */
 952         for (i = 0; i < ci->children_num; ++i) {
 953                 PyTuple_SET_ITEM(children, i, cpy_oconfig_to_pyconfig(ci->children + i, item));
 954         }
 955         tmp = ((Config *) item)->children;
 956         ((Config *) item)->children = children;
 957         Py_XDECREF(tmp);
 958         return item;
 959 }
 960
 961 #ifdef IS_PY3K
 962 static struct PyModuleDef collectdmodule = {
 963         PyModuleDef_HEAD_INIT,
 964         "collectd",   /* name of module */
 965         "The python interface to collectd", /* module documentation, may be NULL */
 966         -1,
 967         cpy_methods
 968 };
 969
 970 PyMODINIT_FUNC PyInit_collectd(void) {
 971         return PyModule_Create(&collectdmodule);
 972 }
 973 #endif
 974
 975 static int cpy_config(oconfig_item_t *ci) {
 976         int i;
 977         PyObject *sys, *tb;
 978         PyObject *sys_path;
 979         PyObject *module;
 980
 981         /* Ok in theory we shouldn't do initialization at this point
 982          * but we have to. In order to give python scripts a chance
 983          * to register a config callback we need to be able to execute
 984          * python code during the config callback so we have to start
 985          * the interpreter here. */
 986         /* Do *not* use the python "thread" module at this point! */
 987
 988 #ifdef IS_PY3K
 989         /* Add a builtin module, before Py_Initialize */
 990         PyImport_AppendInittab("collectd", PyInit_collectd);
 991 #endif
 992
 993         Py_Initialize();
 994
 995         PyType_Ready(&ConfigType);
 996         PyType_Ready(&PluginDataType);
 997         ValuesType.tp_base = &PluginDataType;
 998         PyType_Ready(&ValuesType);
 999         NotificationType.tp_base = &PluginDataType;
1000         PyType_Ready(&NotificationType);
1001         SignedType.tp_base = &PyLong_Type;
1002         PyType_Ready(&SignedType);
1003         UnsignedType.tp_base = &PyLong_Type;
1004         PyType_Ready(&UnsignedType);
1005         sys = PyImport_ImportModule("sys"); /* New reference. */
1006         if (sys == NULL) {
1007                 cpy_log_exception("python initialization");
1008                 return 1;
1009         }
1010         sys_path = PyObject_GetAttrString(sys, "path"); /* New reference. */
1011         Py_DECREF(sys);
1012         if (sys_path == NULL) {
1013                 cpy_log_exception("python initialization");
1014                 return 1;
1015         }
1016 #ifdef IS_PY3K
1017         module = PyImport_ImportModule("collectd");
1018 #else
1019         module = Py_InitModule("collectd", cpy_methods); /* Borrowed reference. */
1020 #endif
1021         PyModule_AddObject(module, "Config", (void *) &ConfigType); /* Steals a reference. */
1022         PyModule_AddObject(module, "Values", (void *) &ValuesType); /* Steals a reference. */
1023         PyModule_AddObject(module, "Notification", (void *) &NotificationType); /* Steals a reference. */
1024         PyModule_AddObject(module, "Signed", (void *) &SignedType); /* Steals a reference. */
1025         PyModule_AddObject(module, "Unsigned", (void *) &UnsignedType); /* Steals a reference. */
1026         PyModule_AddIntConstant(module, "LOG_DEBUG", LOG_DEBUG);
1027         PyModule_AddIntConstant(module, "LOG_INFO", LOG_INFO);
1028         PyModule_AddIntConstant(module, "LOG_NOTICE", LOG_NOTICE);
1029         PyModule_AddIntConstant(module, "LOG_WARNING", LOG_WARNING);
1030         PyModule_AddIntConstant(module, "LOG_ERROR", LOG_ERR);
1031         PyModule_AddIntConstant(module, "NOTIF_FAILURE", NOTIF_FAILURE);
1032         PyModule_AddIntConstant(module, "NOTIF_WARNING", NOTIF_WARNING);
1033         PyModule_AddIntConstant(module, "NOTIF_OKAY", NOTIF_OKAY);
1034         for (i = 0; i < ci->children_num; ++i) {
1035                 oconfig_item_t *item = ci->children + i;
1036
1037                 if (strcasecmp(item->key, "Interactive") == 0) {
1038                         if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_BOOLEAN)
1039                                 continue;
1040                         do_interactive = item->values[0].value.boolean;
1041                 } else if (strcasecmp(item->key, "Encoding") == 0) {
1042                         if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_STRING)
1043                                 continue;
1044                         /* Why is this even necessary? And undocumented? */
1045                         if (PyUnicode_SetDefaultEncoding(item->values[0].value.string))
1046                                 cpy_log_exception("setting default encoding");
1047                 } else if (strcasecmp(item->key, "LogTraces") == 0) {
1048                         if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_BOOLEAN)
1049                                 continue;
1050                         if (!item->values[0].value.boolean) {
1051                                 Py_XDECREF(cpy_format_exception);
1052                                 cpy_format_exception = NULL;
1053                                 continue;
1054                         }
1055                         if (cpy_format_exception)
1056                                 continue;
1057                         tb = PyImport_ImportModule("traceback"); /* New reference. */
1058                         if (tb == NULL) {
1059                                 cpy_log_exception("python initialization");
1060                                 continue;
1061                         }
1062                         cpy_format_exception = PyObject_GetAttrString(tb, "format_exception"); /* New reference. */
1063                         Py_DECREF(tb);
1064                         if (cpy_format_exception == NULL)
1065                                 cpy_log_exception("python initialization");
1066                 } else if (strcasecmp(item->key, "ModulePath") == 0) {
1067                         char *dir = NULL;
1068                         PyObject *dir_object;
1069
1070                         if (cf_util_get_string(item, &dir) != 0)
1071                                 continue;
1072                         dir_object = cpy_string_to_unicode_or_bytes(dir); /* New reference. */
1073                         if (dir_object == NULL) {
1074                                 ERROR("python plugin: Unable to convert \"%s\" to "
1075                                       "a python object.", dir);
1076                                 free(dir);
1077                                 cpy_log_exception("python initialization");
1078                                 continue;
1079                         }
1080                         if (PyList_Append(sys_path, dir_object) != 0) {
1081                                 ERROR("python plugin: Unable to append \"%s\" to "
1082                                       "python module path.", dir);
1083                                 cpy_log_exception("python initialization");
1084                         }
1085                         Py_DECREF(dir_object);
1086                         free(dir);
1087                 } else if (strcasecmp(item->key, "Import") == 0) {
1088                         char *module_name = NULL;
1089                         PyObject *module;
1090
1091                         if (cf_util_get_string(item, &module_name) != 0)
1092                                 continue;
1093                         module = PyImport_ImportModule(module_name); /* New reference. */
1094                         if (module == NULL) {
1095                                 ERROR("python plugin: Error importing module \"%s\".", module_name);
1096                                 cpy_log_exception("importing module");
1097                         }
1098                         free(module_name);
1099                         Py_XDECREF(module);
1100                 } else if (strcasecmp(item->key, "Module") == 0) {
1101                         char *name = NULL;
1102                         cpy_callback_t *c;
1103                         PyObject *ret;
1104
1105                         if (cf_util_get_string(item, &name) != 0)
1106                                 continue;
1107                         for (c = cpy_config_callbacks; c; c = c->next) {
1108                                 if (strcasecmp(c->name + 7, name) == 0)
1109                                         break;
1110                         }
1111                         if (c == NULL) {
1112                                 WARNING("python plugin: Found a configuration for the \"%s\" plugin, "
1113                                         "but the plugin isn't loaded or didn't register "
1114                                         "a configuration callback.", name);
1115                                 free(name);
1116                                 continue;
1117                         }
1118                         free(name);
1119                         if (c->data == NULL)
1120                                 ret = PyObject_CallFunction(c->callback, "N",
1121                                         cpy_oconfig_to_pyconfig(item, NULL)); /* New reference. */
1122                         else
1123                                 ret = PyObject_CallFunction(c->callback, "NO",
1124                                         cpy_oconfig_to_pyconfig(item, NULL), c->data); /* New reference. */
1125                         if (ret == NULL)
1126                                 cpy_log_exception("loading module");
1127                         else
1128                                 Py_DECREF(ret);
1129                 } else {
1130                         WARNING("python plugin: Ignoring unknown config key \"%s\".", item->key);
1131                 }
1132         }
1133         Py_DECREF(sys_path);
1134         return 0;
1135 }
1136
1137 void module_register(void) {
1138         plugin_register_complex_config("python", cpy_config);
1139         plugin_register_init("python", cpy_init);
1140         plugin_register_shutdown("python", cpy_shutdown);
1141 }