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, *val;
 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                 val = Values_New(); /* New reference. */
 432                 v = (Values *) val;
 433                 sstrncpy(v->data.host, value_list->host, sizeof(v->data.host));
 434                 sstrncpy(v->data.type, value_list->type, sizeof(v->data.type));
 435                 sstrncpy(v->data.type_instance, value_list->type_instance, sizeof(v->data.type_instance));
 436                 sstrncpy(v->data.plugin, value_list->plugin, sizeof(v->data.plugin));
 437                 sstrncpy(v->data.plugin_instance, value_list->plugin_instance, sizeof(v->data.plugin_instance));
 438                 v->data.time = value_list->time;
 439                 v->interval = value_list->interval;
 440                 Py_CLEAR(v->values);
 441                 v->values = list;
 442                 Py_CLEAR(v->meta);
 443                 v->meta = dict;
 444                 ret = PyObject_CallFunctionObjArgs(c->callback, v, c->data, (void *) 0); /* New reference. */
 445                 Py_XDECREF(val);
 446                 if (ret == NULL) {
 447                         cpy_log_exception("write callback");
 448                 } else {
 449                         Py_DECREF(ret);
 450                 }
 451         CPY_RELEASE_THREADS
 452         return 0;
 453 }
 454
 455 static int cpy_notification_callback(const notification_t *notification, user_data_t *data) {
 456         cpy_callback_t *c = data->data;
 457         PyObject *ret, *notify;
 458         Notification *n;
 459
 460         CPY_LOCK_THREADS
 461                 notify = Notification_New(); /* New reference. */
 462                 n = (Notification *) notify;
 463                 sstrncpy(n->data.host, notification->host, sizeof(n->data.host));
 464                 sstrncpy(n->data.type, notification->type, sizeof(n->data.type));
 465                 sstrncpy(n->data.type_instance, notification->type_instance, sizeof(n->data.type_instance));
 466                 sstrncpy(n->data.plugin, notification->plugin, sizeof(n->data.plugin));
 467                 sstrncpy(n->data.plugin_instance, notification->plugin_instance, sizeof(n->data.plugin_instance));
 468                 n->data.time = notification->time;
 469                 sstrncpy(n->message, notification->message, sizeof(n->message));
 470                 n->severity = notification->severity;
 471                 ret = PyObject_CallFunctionObjArgs(c->callback, n, c->data, (void *) 0); /* New reference. */
 472                 Py_XDECREF(notify);
 473                 if (ret == NULL) {
 474                         cpy_log_exception("notification callback");
 475                 } else {
 476                         Py_DECREF(ret);
 477                 }
 478         CPY_RELEASE_THREADS
 479         return 0;
 480 }
 481
 482 static void cpy_log_callback(int severity, const char *message, user_data_t *data) {
 483         cpy_callback_t * c = data->data;
 484         PyObject *ret, *text;
 485
 486         CPY_LOCK_THREADS
 487         text = cpy_string_to_unicode_or_bytes(message);
 488         if (c->data == NULL)
 489                 ret = PyObject_CallFunction(c->callback, "iN", severity, text); /* New reference. */
 490         else
 491                 ret = PyObject_CallFunction(c->callback, "iNO", severity, text, c->data); /* New reference. */
 492
 493         if (ret == NULL) {
 494                 /* FIXME */
 495                 /* Do we really want to trigger a log callback because a log callback failed?
 496                  * Probably not. */
 497                 PyErr_Print();
 498                 /* In case someone wanted to be clever, replaced stderr and failed at that. */
 499                 PyErr_Clear();
 500         } else {
 501                 Py_DECREF(ret);
 502         }
 503         CPY_RELEASE_THREADS
 504 }
 505
 506 static void cpy_flush_callback(int timeout, const char *id, user_data_t *data) {
 507         cpy_callback_t * c = data->data;
 508         PyObject *ret, *text;
 509
 510         CPY_LOCK_THREADS
 511         text = cpy_string_to_unicode_or_bytes(id);
 512         if (c->data == NULL)
 513                 ret = PyObject_CallFunction(c->callback, "iN", timeout, text); /* New reference. */
 514         else
 515                 ret = PyObject_CallFunction(c->callback, "iNO", timeout, text, c->data); /* New reference. */
 516
 517         if (ret == NULL) {
 518                 cpy_log_exception("flush callback");
 519         } else {
 520                 Py_DECREF(ret);
 521         }
 522         CPY_RELEASE_THREADS
 523 }
 524
 525 static PyObject *cpy_register_generic(cpy_callback_t **list_head, PyObject *args, PyObject *kwds) {
 526         char buf[512];
 527         cpy_callback_t *c;
 528         const char *name = NULL;
 529         PyObject *callback = NULL, *data = NULL, *mod = NULL;
 530         static char *kwlist[] = {"callback", "data", "name", NULL};
 531
 532         if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oet", kwlist, &callback, &data, NULL, &name) == 0) return NULL;
 533         if (PyCallable_Check(callback) == 0) {
 534                 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
 535                 return NULL;
 536         }
 537         cpy_build_name(buf, sizeof(buf), callback, name);
 538
 539         Py_INCREF(callback);
 540         Py_XINCREF(data);
 541         c = malloc(sizeof(*c));
 542         c->name = strdup(buf);
 543         c->callback = callback;
 544         c->data = data;
 545         c->next = *list_head;
 546         *list_head = c;
 547         Py_XDECREF(mod);
 548         return cpy_string_to_unicode_or_bytes(buf);
 549 }
 550
 551 static PyObject *cpy_flush(cpy_callback_t **list_head, PyObject *args, PyObject *kwds) {
 552         int timeout = -1;
 553         const char *plugin = NULL, *identifier = NULL;
 554         static char *kwlist[] = {"plugin", "timeout", "identifier", NULL};
 555
 556         if (PyArg_ParseTupleAndKeywords(args, kwds, "|etiet", kwlist, NULL, &plugin, &timeout, NULL, &identifier) == 0) return NULL;
 557         Py_BEGIN_ALLOW_THREADS
 558         plugin_flush(plugin, timeout, identifier);
 559         Py_END_ALLOW_THREADS
 560         Py_RETURN_NONE;
 561 }
 562
 563 static PyObject *cpy_register_config(PyObject *self, PyObject *args, PyObject *kwds) {
 564         return cpy_register_generic(&cpy_config_callbacks, args, kwds);
 565 }
 566
 567 static PyObject *cpy_register_init(PyObject *self, PyObject *args, PyObject *kwds) {
 568         return cpy_register_generic(&cpy_init_callbacks, args, kwds);
 569 }
 570
 571 typedef int reg_function_t(const char *name, void *callback, void *data);
 572
 573 static PyObject *cpy_register_generic_userdata(void *reg, void *handler, PyObject *args, PyObject *kwds) {
 574         char buf[512];
 575         reg_function_t *register_function = (reg_function_t *) reg;
 576         cpy_callback_t *c = NULL;
 577         user_data_t *user_data = NULL;
 578         const char *name = NULL;
 579         PyObject *callback = NULL, *data = NULL;
 580         static char *kwlist[] = {"callback", "data", "name", NULL};
 581
 582         if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oet", kwlist, &callback, &data, NULL, &name) == 0) return NULL;
 583         if (PyCallable_Check(callback) == 0) {
 584                 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
 585                 return NULL;
 586         }
 587         cpy_build_name(buf, sizeof(buf), callback, name);
 588
 589         Py_INCREF(callback);
 590         Py_XINCREF(data);
 591         c = malloc(sizeof(*c));
 592         c->name = strdup(buf);
 593         c->callback = callback;
 594         c->data = data;
 595         c->next = NULL;
 596         user_data = malloc(sizeof(*user_data));
 597         user_data->free_func = cpy_destroy_user_data;
 598         user_data->data = c;
 599         register_function(buf, handler, user_data);
 600         return cpy_string_to_unicode_or_bytes(buf);
 601 }
 602
 603 static PyObject *cpy_register_read(PyObject *self, PyObject *args, PyObject *kwds) {
 604         char buf[512];
 605         cpy_callback_t *c = NULL;
 606         user_data_t *user_data = NULL;
 607         double interval = 0;
 608         const char *name = NULL;
 609         PyObject *callback = NULL, *data = NULL;
 610         struct timespec ts;
 611         static char *kwlist[] = {"callback", "interval", "data", "name", NULL};
 612
 613         if (PyArg_ParseTupleAndKeywords(args, kwds, "O|dOet", kwlist, &callback, &interval, &data, NULL, &name) == 0) return NULL;
 614         if (PyCallable_Check(callback) == 0) {
 615                 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
 616                 return NULL;
 617         }
 618         cpy_build_name(buf, sizeof(buf), callback, name);
 619
 620         Py_INCREF(callback);
 621         Py_XINCREF(data);
 622         c = malloc(sizeof(*c));
 623         c->name = strdup(buf);
 624         c->callback = callback;
 625         c->data = data;
 626         c->next = NULL;
 627         user_data = malloc(sizeof(*user_data));
 628         user_data->free_func = cpy_destroy_user_data;
 629         user_data->data = c;
 630         ts.tv_sec = interval;
 631         ts.tv_nsec = (interval - ts.tv_sec) * 1000000000;
 632         plugin_register_complex_read(/* group = */ NULL, buf,
 633                         cpy_read_callback, &ts, user_data);
 634         return cpy_string_to_unicode_or_bytes(buf);
 635 }
 636
 637 static PyObject *cpy_register_log(PyObject *self, PyObject *args, PyObject *kwds) {
 638         return cpy_register_generic_userdata((void *) plugin_register_log,
 639                         (void *) cpy_log_callback, args, kwds);
 640 }
 641
 642 static PyObject *cpy_register_write(PyObject *self, PyObject *args, PyObject *kwds) {
 643         return cpy_register_generic_userdata((void *) plugin_register_write,
 644                         (void *) cpy_write_callback, args, kwds);
 645 }
 646
 647 static PyObject *cpy_register_notification(PyObject *self, PyObject *args, PyObject *kwds) {
 648         return cpy_register_generic_userdata((void *) plugin_register_notification,
 649                         (void *) cpy_notification_callback, args, kwds);
 650 }
 651
 652 static PyObject *cpy_register_flush(PyObject *self, PyObject *args, PyObject *kwds) {
 653         return cpy_register_generic_userdata((void *) plugin_register_flush,
 654                         (void *) cpy_flush_callback, args, kwds);
 655 }
 656
 657 static PyObject *cpy_register_shutdown(PyObject *self, PyObject *args, PyObject *kwds) {
 658         return cpy_register_generic(&cpy_shutdown_callbacks, args, kwds);
 659 }
 660
 661 static PyObject *cpy_error(PyObject *self, PyObject *args) {
 662         const char *text;
 663         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 664         Py_BEGIN_ALLOW_THREADS
 665         plugin_log(LOG_ERR, "%s", text);
 666         Py_END_ALLOW_THREADS
 667         Py_RETURN_NONE;
 668 }
 669
 670 static PyObject *cpy_warning(PyObject *self, PyObject *args) {
 671         const char *text;
 672         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 673         Py_BEGIN_ALLOW_THREADS
 674         plugin_log(LOG_WARNING, "%s", text);
 675         Py_END_ALLOW_THREADS
 676         Py_RETURN_NONE;
 677 }
 678
 679 static PyObject *cpy_notice(PyObject *self, PyObject *args) {
 680         const char *text;
 681         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 682         Py_BEGIN_ALLOW_THREADS
 683         plugin_log(LOG_NOTICE, "%s", text);
 684         Py_END_ALLOW_THREADS
 685         Py_RETURN_NONE;
 686 }
 687
 688 static PyObject *cpy_info(PyObject *self, PyObject *args) {
 689         const char *text;
 690         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 691         Py_BEGIN_ALLOW_THREADS
 692         plugin_log(LOG_INFO, "%s", text);
 693         Py_END_ALLOW_THREADS
 694         Py_RETURN_NONE;
 695 }
 696
 697 static PyObject *cpy_debug(PyObject *self, PyObject *args) {
 698 #ifdef COLLECT_DEBUG
 699         const char *text;
 700         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 701         Py_BEGIN_ALLOW_THREADS
 702         plugin_log(LOG_DEBUG, "%s", text);
 703         Py_END_ALLOW_THREADS
 704 #endif
 705         Py_RETURN_NONE;
 706 }
 707
 708 static PyObject *cpy_unregister_generic(cpy_callback_t **list_head, PyObject *arg, const char *desc) {
 709         char buf[512];
 710         const char *name;
 711         cpy_callback_t *prev = NULL, *tmp;
 712
 713         Py_INCREF(arg);
 714         name = cpy_unicode_or_bytes_to_string(&arg);
 715         if (name == NULL) {
 716                 PyErr_Clear();
 717                 if (!PyCallable_Check(arg)) {
 718                         PyErr_SetString(PyExc_TypeError, "This function needs a string or a callable object as its only parameter.");
 719                         Py_DECREF(arg);
 720                         return NULL;
 721                 }
 722                 cpy_build_name(buf, sizeof(buf), arg, NULL);
 723                 name = buf;
 724         }
 725         for (tmp = *list_head; tmp; prev = tmp, tmp = tmp->next)
 726                 if (strcmp(name, tmp->name) == 0)
 727                         break;
 728
 729         Py_DECREF(arg);
 730         if (tmp == NULL) {
 731                 PyErr_Format(PyExc_RuntimeError, "Unable to unregister %s callback '%s'.", desc, name);
 732                 return NULL;
 733         }
 734         /* Yes, this is actually save. To call this function the caller has to
 735          * hold the GIL. Well, save as long as there is only one GIL anyway ... */
 736         if (prev == NULL)
 737                 *list_head = tmp->next;
 738         else
 739                 prev->next = tmp->next;
 740         cpy_destroy_user_data(tmp);
 741         Py_RETURN_NONE;
 742 }
 743
 744 typedef int cpy_unregister_function_t(const char *name);
 745
 746 static PyObject *cpy_unregister_generic_userdata(cpy_unregister_function_t *unreg, PyObject *arg, const char *desc) {
 747         char buf[512];
 748         const char *name;
 749
 750         Py_INCREF(arg);
 751         name = cpy_unicode_or_bytes_to_string(&arg);
 752         if (name == NULL) {
 753                 PyErr_Clear();
 754                 if (!PyCallable_Check(arg)) {
 755                         PyErr_SetString(PyExc_TypeError, "This function needs a string or a callable object as its only parameter.");
 756                         Py_DECREF(arg);
 757                         return NULL;
 758                 }
 759                 cpy_build_name(buf, sizeof(buf), arg, NULL);
 760                 name = buf;
 761         }
 762         if (unreg(name) == 0) {
 763                 Py_DECREF(arg);
 764                 Py_RETURN_NONE;
 765         }
 766         PyErr_Format(PyExc_RuntimeError, "Unable to unregister %s callback '%s'.", desc, name);
 767         Py_DECREF(arg);
 768         return NULL;
 769 }
 770
 771 static PyObject *cpy_unregister_log(PyObject *self, PyObject *arg) {
 772         return cpy_unregister_generic_userdata(plugin_unregister_log, arg, "log");
 773 }
 774
 775 static PyObject *cpy_unregister_init(PyObject *self, PyObject *arg) {
 776         return cpy_unregister_generic(&cpy_init_callbacks, arg, "init");
 777 }
 778
 779 static PyObject *cpy_unregister_config(PyObject *self, PyObject *arg) {
 780         return cpy_unregister_generic(&cpy_config_callbacks, arg, "config");
 781 }
 782
 783 static PyObject *cpy_unregister_read(PyObject *self, PyObject *arg) {
 784         return cpy_unregister_generic_userdata(plugin_unregister_read, arg, "read");
 785 }
 786
 787 static PyObject *cpy_unregister_write(PyObject *self, PyObject *arg) {
 788         return cpy_unregister_generic_userdata(plugin_unregister_write, arg, "write");
 789 }
 790
 791 static PyObject *cpy_unregister_notification(PyObject *self, PyObject *arg) {
 792         return cpy_unregister_generic_userdata(plugin_unregister_notification, arg, "notification");
 793 }
 794
 795 static PyObject *cpy_unregister_flush(PyObject *self, PyObject *arg) {
 796         return cpy_unregister_generic_userdata(plugin_unregister_flush, arg, "flush");
 797 }
 798
 799 static PyObject *cpy_unregister_shutdown(PyObject *self, PyObject *arg) {
 800         return cpy_unregister_generic(&cpy_shutdown_callbacks, arg, "shutdown");
 801 }
 802
 803 static PyMethodDef cpy_methods[] = {
 804         {"debug", cpy_debug, METH_VARARGS, log_doc},
 805         {"info", cpy_info, METH_VARARGS, log_doc},
 806         {"notice", cpy_notice, METH_VARARGS, log_doc},
 807         {"warning", cpy_warning, METH_VARARGS, log_doc},
 808         {"error", cpy_error, METH_VARARGS, log_doc},
 809         {"flush", (PyCFunction) cpy_flush, METH_VARARGS | METH_KEYWORDS, flush_doc},
 810         {"register_log", (PyCFunction) cpy_register_log, METH_VARARGS | METH_KEYWORDS, reg_log_doc},
 811         {"register_init", (PyCFunction) cpy_register_init, METH_VARARGS | METH_KEYWORDS, reg_init_doc},
 812         {"register_config", (PyCFunction) cpy_register_config, METH_VARARGS | METH_KEYWORDS, reg_config_doc},
 813         {"register_read", (PyCFunction) cpy_register_read, METH_VARARGS | METH_KEYWORDS, reg_read_doc},
 814         {"register_write", (PyCFunction) cpy_register_write, METH_VARARGS | METH_KEYWORDS, reg_write_doc},
 815         {"register_notification", (PyCFunction) cpy_register_notification, METH_VARARGS | METH_KEYWORDS, reg_notification_doc},
 816         {"register_flush", (PyCFunction) cpy_register_flush, METH_VARARGS | METH_KEYWORDS, reg_flush_doc},
 817         {"register_shutdown", (PyCFunction) cpy_register_shutdown, METH_VARARGS | METH_KEYWORDS, reg_shutdown_doc},
 818         {"unregister_log", cpy_unregister_log, METH_O, unregister_doc},
 819         {"unregister_init", cpy_unregister_init, METH_O, unregister_doc},
 820         {"unregister_config", cpy_unregister_config, METH_O, unregister_doc},
 821         {"unregister_read", cpy_unregister_read, METH_O, unregister_doc},
 822         {"unregister_write", cpy_unregister_write, METH_O, unregister_doc},
 823         {"unregister_notification", cpy_unregister_notification, METH_O, unregister_doc},
 824         {"unregister_flush", cpy_unregister_flush, METH_O, unregister_doc},
 825         {"unregister_shutdown", cpy_unregister_shutdown, METH_O, unregister_doc},
 826         {0, 0, 0, 0}
 827 };
 828
 829 static int cpy_shutdown(void) {
 830         cpy_callback_t *c;
 831         PyObject *ret;
 832
 833         /* This can happen if the module was loaded but not configured. */
 834         if (state != NULL)
 835                 PyEval_RestoreThread(state);
 836
 837         for (c = cpy_shutdown_callbacks; c; c = c->next) {
 838                 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
 839                 if (ret == NULL)
 840                         cpy_log_exception("shutdown callback");
 841                 else
 842                         Py_DECREF(ret);
 843         }
 844         PyErr_Print();
 845         Py_Finalize();
 846         return 0;
 847 }
 848
 849 static void cpy_int_handler(int sig) {
 850         return;
 851 }
 852
 853 static void *cpy_interactive(void *data) {
 854         sigset_t sigset;
 855         struct sigaction sig_int_action, old;
 856
 857         /* Signal handler in a plugin? Bad stuff, but the best way to
 858          * handle it I guess. In an interactive session people will
 859          * press Ctrl+C at some time, which will generate a SIGINT.
 860          * This will cause collectd to shutdown, thus killing the
 861          * interactive interpreter, and leaving the terminal in a
 862          * mess. Chances are, this isn't what the user wanted to do.
 863          *
 864          * So this is the plan:
 865          * 1. Block SIGINT in the main thread.
 866          * 2. Install our own signal handler that does nothing.
 867          * 3. Unblock SIGINT in the interactive thread.
 868          *
 869          * This will make sure that SIGINT won't kill collectd but
 870          * still interrupt syscalls like sleep and pause.
 871          * It does not raise a KeyboardInterrupt exception because so
 872          * far nobody managed to figure out how to do that. */
 873         memset (&sig_int_action, '\0', sizeof (sig_int_action));
 874         sig_int_action.sa_handler = cpy_int_handler;
 875         sigaction (SIGINT, &sig_int_action, &old);
 876
 877         sigemptyset(&sigset);
 878         sigaddset(&sigset, SIGINT);
 879         pthread_sigmask(SIG_UNBLOCK, &sigset, NULL);
 880         PyEval_AcquireThread(state);
 881         if (PyImport_ImportModule("readline") == NULL) {
 882                 /* This interactive session will suck. */
 883                 cpy_log_exception("interactive session init");
 884         }
 885         PyRun_InteractiveLoop(stdin, "<stdin>");
 886         PyErr_Print();
 887         PyEval_ReleaseThread(state);
 888         NOTICE("python: Interactive interpreter exited, stopping collectd ...");
 889         /* Restore the original collectd SIGINT handler and raise SIGINT.
 890          * The main thread still has SIGINT blocked and there's nothing we
 891          * can do about that so this thread will handle it. But that's not
 892          * important, except that it won't interrupt the main loop and so
 893          * it might take a few seconds before collectd really shuts down. */
 894         sigaction (SIGINT, &old, NULL);
 895         raise(SIGINT);
 896         pause();
 897         return NULL;
 898 }
 899
 900 static int cpy_init(void) {
 901         cpy_callback_t *c;
 902         PyObject *ret;
 903         static pthread_t thread;
 904         sigset_t sigset;
 905
 906         if (!Py_IsInitialized()) {
 907                 WARNING("python: Plugin loaded but not configured.");
 908                 plugin_unregister_shutdown("python");
 909                 return 0;
 910         }
 911         PyEval_InitThreads();
 912         /* Now it's finally OK to use python threads. */
 913         for (c = cpy_init_callbacks; c; c = c->next) {
 914                 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
 915                 if (ret == NULL)
 916                         cpy_log_exception("init callback");
 917                 else
 918                         Py_DECREF(ret);
 919         }
 920         sigemptyset(&sigset);
 921         sigaddset(&sigset, SIGINT);
 922         pthread_sigmask(SIG_BLOCK, &sigset, NULL);
 923         state = PyEval_SaveThread();
 924         if (do_interactive) {
 925                 if (pthread_create(&thread, NULL, cpy_interactive, NULL)) {
 926                         ERROR("python: Error creating thread for interactive interpreter.");
 927                 }
 928         }
 929
 930         return 0;
 931 }
 932
 933 static PyObject *cpy_oconfig_to_pyconfig(oconfig_item_t *ci, PyObject *parent) {
 934         int i;
 935         PyObject *item, *values, *children, *tmp;
 936
 937         if (parent == NULL)
 938                 parent = Py_None;
 939
 940         values = PyTuple_New(ci->values_num); /* New reference. */
 941         for (i = 0; i < ci->values_num; ++i) {
 942                 if (ci->values[i].type == OCONFIG_TYPE_STRING) {
 943                         PyTuple_SET_ITEM(values, i, cpy_string_to_unicode_or_bytes(ci->values[i].value.string));
 944                 } else if (ci->values[i].type == OCONFIG_TYPE_NUMBER) {
 945                         PyTuple_SET_ITEM(values, i, PyFloat_FromDouble(ci->values[i].value.number));
 946                 } else if (ci->values[i].type == OCONFIG_TYPE_BOOLEAN) {
 947                         PyTuple_SET_ITEM(values, i, PyBool_FromLong(ci->values[i].value.boolean));
 948                 }
 949         }
 950
 951         tmp = cpy_string_to_unicode_or_bytes(ci->key);
 952         item = PyObject_CallFunction((void *) &ConfigType, "NONO", tmp, parent, values, Py_None);
 953         if (item == NULL)
 954                 return NULL;
 955         children = PyTuple_New(ci->children_num); /* New reference. */
 956         for (i = 0; i < ci->children_num; ++i) {
 957                 PyTuple_SET_ITEM(children, i, cpy_oconfig_to_pyconfig(ci->children + i, item));
 958         }
 959         tmp = ((Config *) item)->children;
 960         ((Config *) item)->children = children;
 961         Py_XDECREF(tmp);
 962         return item;
 963 }
 964
 965 #ifdef IS_PY3K
 966 static struct PyModuleDef collectdmodule = {
 967         PyModuleDef_HEAD_INIT,
 968         "collectd",   /* name of module */
 969         "The python interface to collectd", /* module documentation, may be NULL */
 970         -1,
 971         cpy_methods
 972 };
 973
 974 PyMODINIT_FUNC PyInit_collectd(void) {
 975         return PyModule_Create(&collectdmodule);
 976 }
 977 #endif
 978
 979 static int cpy_config(oconfig_item_t *ci) {
 980         int i;
 981         PyObject *sys, *tb;
 982         PyObject *sys_path;
 983         PyObject *module;
 984
 985         /* Ok in theory we shouldn't do initialization at this point
 986          * but we have to. In order to give python scripts a chance
 987          * to register a config callback we need to be able to execute
 988          * python code during the config callback so we have to start
 989          * the interpreter here. */
 990         /* Do *not* use the python "thread" module at this point! */
 991
 992 #ifdef IS_PY3K
 993         /* Add a builtin module, before Py_Initialize */
 994         PyImport_AppendInittab("collectd", PyInit_collectd);
 995 #endif
 996
 997         Py_Initialize();
 998
 999         PyType_Ready(&ConfigType);
1000         PyType_Ready(&PluginDataType);
1001         ValuesType.tp_base = &PluginDataType;
1002         PyType_Ready(&ValuesType);
1003         NotificationType.tp_base = &PluginDataType;
1004         PyType_Ready(&NotificationType);
1005         SignedType.tp_base = &PyLong_Type;
1006         PyType_Ready(&SignedType);
1007         UnsignedType.tp_base = &PyLong_Type;
1008         PyType_Ready(&UnsignedType);
1009         sys = PyImport_ImportModule("sys"); /* New reference. */
1010         if (sys == NULL) {
1011                 cpy_log_exception("python initialization");
1012                 return 1;
1013         }
1014         sys_path = PyObject_GetAttrString(sys, "path"); /* New reference. */
1015         Py_DECREF(sys);
1016         if (sys_path == NULL) {
1017                 cpy_log_exception("python initialization");
1018                 return 1;
1019         }
1020 #ifdef IS_PY3K
1021         module = PyImport_ImportModule("collectd");
1022 #else
1023         module = Py_InitModule("collectd", cpy_methods); /* Borrowed reference. */
1024 #endif
1025         PyModule_AddObject(module, "Config", (void *) &ConfigType); /* Steals a reference. */
1026         PyModule_AddObject(module, "Values", (void *) &ValuesType); /* Steals a reference. */
1027         PyModule_AddObject(module, "Notification", (void *) &NotificationType); /* Steals a reference. */
1028         PyModule_AddObject(module, "Signed", (void *) &SignedType); /* Steals a reference. */
1029         PyModule_AddObject(module, "Unsigned", (void *) &UnsignedType); /* Steals a reference. */
1030         PyModule_AddIntConstant(module, "LOG_DEBUG", LOG_DEBUG);
1031         PyModule_AddIntConstant(module, "LOG_INFO", LOG_INFO);
1032         PyModule_AddIntConstant(module, "LOG_NOTICE", LOG_NOTICE);
1033         PyModule_AddIntConstant(module, "LOG_WARNING", LOG_WARNING);
1034         PyModule_AddIntConstant(module, "LOG_ERROR", LOG_ERR);
1035         PyModule_AddIntConstant(module, "NOTIF_FAILURE", NOTIF_FAILURE);
1036         PyModule_AddIntConstant(module, "NOTIF_WARNING", NOTIF_WARNING);
1037         PyModule_AddIntConstant(module, "NOTIF_OKAY", NOTIF_OKAY);
1038         for (i = 0; i < ci->children_num; ++i) {
1039                 oconfig_item_t *item = ci->children + i;
1040
1041                 if (strcasecmp(item->key, "Interactive") == 0) {
1042                         if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_BOOLEAN)
1043                                 continue;
1044                         do_interactive = item->values[0].value.boolean;
1045                 } else if (strcasecmp(item->key, "Encoding") == 0) {
1046                         if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_STRING)
1047                                 continue;
1048                         /* Why is this even necessary? And undocumented? */
1049                         if (PyUnicode_SetDefaultEncoding(item->values[0].value.string))
1050                                 cpy_log_exception("setting default encoding");
1051                 } else if (strcasecmp(item->key, "LogTraces") == 0) {
1052                         if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_BOOLEAN)
1053                                 continue;
1054                         if (!item->values[0].value.boolean) {
1055                                 Py_XDECREF(cpy_format_exception);
1056                                 cpy_format_exception = NULL;
1057                                 continue;
1058                         }
1059                         if (cpy_format_exception)
1060                                 continue;
1061                         tb = PyImport_ImportModule("traceback"); /* New reference. */
1062                         if (tb == NULL) {
1063                                 cpy_log_exception("python initialization");
1064                                 continue;
1065                         }
1066                         cpy_format_exception = PyObject_GetAttrString(tb, "format_exception"); /* New reference. */
1067                         Py_DECREF(tb);
1068                         if (cpy_format_exception == NULL)
1069                                 cpy_log_exception("python initialization");
1070                 } else if (strcasecmp(item->key, "ModulePath") == 0) {
1071                         char *dir = NULL;
1072                         PyObject *dir_object;
1073
1074                         if (cf_util_get_string(item, &dir) != 0)
1075                                 continue;
1076                         dir_object = cpy_string_to_unicode_or_bytes(dir); /* New reference. */
1077                         if (dir_object == NULL) {
1078                                 ERROR("python plugin: Unable to convert \"%s\" to "
1079                                       "a python object.", dir);
1080                                 free(dir);
1081                                 cpy_log_exception("python initialization");
1082                                 continue;
1083                         }
1084                         if (PyList_Append(sys_path, dir_object) != 0) {
1085                                 ERROR("python plugin: Unable to append \"%s\" to "
1086                                       "python module path.", dir);
1087                                 cpy_log_exception("python initialization");
1088                         }
1089                         Py_DECREF(dir_object);
1090                         free(dir);
1091                 } else if (strcasecmp(item->key, "Import") == 0) {
1092                         char *module_name = NULL;
1093                         PyObject *module;
1094
1095                         if (cf_util_get_string(item, &module_name) != 0)
1096                                 continue;
1097                         module = PyImport_ImportModule(module_name); /* New reference. */
1098                         if (module == NULL) {
1099                                 ERROR("python plugin: Error importing module \"%s\".", module_name);
1100                                 cpy_log_exception("importing module");
1101                         }
1102                         free(module_name);
1103                         Py_XDECREF(module);
1104                 } else if (strcasecmp(item->key, "Module") == 0) {
1105                         char *name = NULL;
1106                         cpy_callback_t *c;
1107                         PyObject *ret;
1108
1109                         if (cf_util_get_string(item, &name) != 0)
1110                                 continue;
1111                         for (c = cpy_config_callbacks; c; c = c->next) {
1112                                 if (strcasecmp(c->name + 7, name) == 0)
1113                                         break;
1114                         }
1115                         if (c == NULL) {
1116                                 WARNING("python plugin: Found a configuration for the \"%s\" plugin, "
1117                                         "but the plugin isn't loaded or didn't register "
1118                                         "a configuration callback.", name);
1119                                 free(name);
1120                                 continue;
1121                         }
1122                         free(name);
1123                         if (c->data == NULL)
1124                                 ret = PyObject_CallFunction(c->callback, "N",
1125                                         cpy_oconfig_to_pyconfig(item, NULL)); /* New reference. */
1126                         else
1127                                 ret = PyObject_CallFunction(c->callback, "NO",
1128                                         cpy_oconfig_to_pyconfig(item, NULL), c->data); /* New reference. */
1129                         if (ret == NULL)
1130                                 cpy_log_exception("loading module");
1131                         else
1132                                 Py_DECREF(ret);
1133                 } else {
1134                         WARNING("python plugin: Ignoring unknown config key \"%s\".", item->key);
1135                 }
1136         }
1137         Py_DECREF(sys_path);
1138         return 0;
1139 }
1140
1141 void module_register(void) {
1142         plugin_register_complex_config("python", cpy_config);
1143         plugin_register_init("python", cpy_init);
1144         plugin_register_shutdown("python", cpy_shutdown);
1145 }