src/python.c

   1 /**
   2  * collectd - src/python.c
   3  * Copyright (C) 2009  Sven Trenkel
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the "Software"),
   7  * to deal in the Software without restriction, including without limitation
   8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   9  * and/or sell copies of the Software, and to permit persons to whom the
  10  * Software is furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be included in
  13  * all copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  18  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  21  * DEALINGS IN THE SOFTWARE.
  22  *
  23  * Authors:
  24  *   Sven Trenkel <collectd at semidefinite.de>
  25  **/
  26
  27 #include <Python.h>
  28 #include <structmember.h>
  29
  30 #include <signal.h>
  31
  32 #include "collectd.h"
  33
  34 #include "common.h"
  35
  36 #include "cpython.h"
  37
  38 typedef struct cpy_callback_s {
  39         char *name;
  40         PyObject *callback;
  41         PyObject *data;
  42         struct cpy_callback_s *next;
  43 } cpy_callback_t;
  44
  45 static char log_doc[] = "This function sends a string to all logging plugins.";
  46
  47 static char get_ds_doc[] = "get_dataset(name) -> definition\n"
  48                 "\n"
  49                 "Returns the definition of a dataset specified by name.\n"
  50                 "\n"
  51                 "'name' is a string specifying the dataset to query.\n"
  52                 "'definition' is a list of 4-tuples. Every tuple represents a \n"
  53                 "    data source within the data set and its 4 values are the \n"
  54                 "    name, type, min and max value.\n"
  55                 "    'name' is a string.\n"
  56                 "    'type' is a string that is equal to either DS_TYPE_COUNTER,\n"
  57                 "        DS_TYPE_GAUGE, DS_TYPE_DERIVE or DS_TYPE_ABSOLUTE.\n"
  58                 "    'min' and 'max' are either a float or None.";
  59
  60 static char flush_doc[] = "flush([plugin][, timeout][, identifier]) -> None\n"
  61                 "\n"
  62                 "Flushes the cache of another plugin.";
  63
  64 static char unregister_doc[] = "Unregisters a callback. This function needs exactly one parameter either\n"
  65                 "the function to unregister or the callback identifier to unregister.";
  66
  67 static char reg_log_doc[] = "register_log(callback[, data][, name]) -> identifier\n"
  68                 "\n"
  69                 "Register a callback function for log messages.\n"
  70                 "\n"
  71                 "'callback' is a callable object that will be called every time something\n"
  72                 "    is logged.\n"
  73                 "'data' is an optional object that will be passed back to the callback\n"
  74                 "    function every time it is called.\n"
  75                 "'name' is an optional identifier for this callback. The default name\n"
  76                 "    is 'python.<module>'.\n"
  77                 "    Every callback needs a unique identifier, so if you want to\n"
  78                 "    register this callback multiple time from the same module you need\n"
  79                 "    to specify a name here.\n"
  80                 "'identifier' is the full identifier assigned to this callback.\n"
  81                 "\n"
  82                 "The callback function will be called with two or three parameters:\n"
  83                 "severity: An integer that should be compared to the LOG_ constants.\n"
  84                 "message: The text to be logged.\n"
  85                 "data: The optional data parameter passed to the register function.\n"
  86                 "    If the parameter was omitted it will be omitted here, too.";
  87
  88 static char reg_init_doc[] = "register_init(callback[, data][, name]) -> identifier\n"
  89                 "\n"
  90                 "Register a callback function that will be executed once after the config.\n"
  91                 "file has been read, all plugins heve been loaded and the collectd has\n"
  92                 "forked into the background.\n"
  93                 "\n"
  94                 "'callback' is a callable object that will be executed.\n"
  95                 "'data' is an optional object that will be passed back to the callback\n"
  96                 "    function when it is called.\n"
  97                 "'name' is an optional identifier for this callback. The default name\n"
  98                 "    is 'python.<module>'.\n"
  99                 "    Every callback needs a unique identifier, so if you want to\n"
 100                 "    register this callback multiple time from the same module you need\n"
 101                 "    to specify a name here.\n"
 102                 "'identifier' is the full identifier assigned to this callback.\n"
 103                 "\n"
 104                 "The callback function will be called without parameters, except for\n"
 105                 "data if it was supplied.";
 106
 107 static char reg_config_doc[] = "register_config(callback[, data][, name]) -> identifier\n"
 108                 "\n"
 109                 "Register a callback function for config file entries.\n"
 110                 "'callback' is a callable object that will be called for every config block.\n"
 111                 "'data' is an optional object that will be passed back to the callback\n"
 112                 "    function every time it is called.\n"
 113                 "'name' is an optional identifier for this callback. The default name\n"
 114                 "    is 'python.<module>'.\n"
 115                 "    Every callback needs a unique identifier, so if you want to\n"
 116                 "    register this callback multiple time from the same module you need\n"
 117                 "    to specify a name here.\n"
 118                 "'identifier' is the full identifier assigned to this callback.\n"
 119                 "\n"
 120                 "The callback function will be called with one or two parameters:\n"
 121                 "config: A Config object.\n"
 122                 "data: The optional data parameter passed to the register function.\n"
 123                 "    If the parameter was omitted it will be omitted here, too.";
 124
 125 static char reg_read_doc[] = "register_read(callback[, interval][, data][, name]) -> identifier\n"
 126                 "\n"
 127                 "Register a callback function for reading data. It will just be called\n"
 128                 "in a fixed interval to signal that it's time to dispatch new values.\n"
 129                 "'callback' is a callable object that will be called every time something\n"
 130                 "    is logged.\n"
 131                 "'interval' is the number of seconds between between calls to the callback\n"
 132                 "    function. Full float precision is supported here.\n"
 133                 "'data' is an optional object that will be passed back to the callback\n"
 134                 "    function every time it is called.\n"
 135                 "'name' is an optional identifier for this callback. The default name\n"
 136                 "    is 'python.<module>'.\n"
 137                 "    Every callback needs a unique identifier, so if you want to\n"
 138                 "    register this callback multiple time from the same module you need\n"
 139                 "    to specify a name here.\n"
 140                 "'identifier' is the full identifier assigned to this callback.\n"
 141                 "\n"
 142                 "The callback function will be called without parameters, except for\n"
 143                 "data if it was supplied.";
 144
 145 static char reg_write_doc[] = "register_write(callback[, data][, name]) -> identifier\n"
 146                 "\n"
 147                 "Register a callback function to receive values dispatched by other plugins.\n"
 148                 "'callback' is a callable object that will be called every time a value\n"
 149                 "    is dispatched.\n"
 150                 "'data' is an optional object that will be passed back to the callback\n"
 151                 "    function every time it is called.\n"
 152                 "'name' is an optional identifier for this callback. The default name\n"
 153                 "    is 'python.<module>'.\n"
 154                 "    Every callback needs a unique identifier, so if you want to\n"
 155                 "    register this callback multiple time from the same module you need\n"
 156                 "    to specify a name here.\n"
 157                 "'identifier' is the full identifier assigned to this callback.\n"
 158                 "\n"
 159                 "The callback function will be called with one or two parameters:\n"
 160                 "values: A Values object which is a copy of the dispatched values.\n"
 161                 "data: The optional data parameter passed to the register function.\n"
 162                 "    If the parameter was omitted it will be omitted here, too.";
 163
 164 static char reg_notification_doc[] = "register_notification(callback[, data][, name]) -> identifier\n"
 165                 "\n"
 166                 "Register a callback function for notifications.\n"
 167                 "'callback' is a callable object that will be called every time a notification\n"
 168                 "    is dispatched.\n"
 169                 "'data' is an optional object that will be passed back to the callback\n"
 170                 "    function every time it is called.\n"
 171                 "'name' is an optional identifier for this callback. The default name\n"
 172                 "    is 'python.<module>'.\n"
 173                 "    Every callback needs a unique identifier, so if you want to\n"
 174                 "    register this callback multiple time from the same module you need\n"
 175                 "    to specify a name here.\n"
 176                 "'identifier' is the full identifier assigned to this callback.\n"
 177                 "\n"
 178                 "The callback function will be called with one or two parameters:\n"
 179                 "notification: A copy of the notification that was dispatched.\n"
 180                 "data: The optional data parameter passed to the register function.\n"
 181                 "    If the parameter was omitted it will be omitted here, too.";
 182
 183 static char reg_flush_doc[] = "register_flush(callback[, data][, name]) -> identifier\n"
 184                 "\n"
 185                 "Register a callback function for flush messages.\n"
 186                 "'callback' is a callable object that will be called every time a plugin\n"
 187                 "    requests a flush for either this or all plugins.\n"
 188                 "'data' is an optional object that will be passed back to the callback\n"
 189                 "    function every time it is called.\n"
 190                 "'name' is an optional identifier for this callback. The default name\n"
 191                 "    is 'python.<module>'.\n"
 192                 "    Every callback needs a unique identifier, so if you want to\n"
 193                 "    register this callback multiple time from the same module you need\n"
 194                 "    to specify a name here.\n"
 195                 "'identifier' is the full identifier assigned to this callback.\n"
 196                 "\n"
 197                 "The callback function will be called with two or three parameters:\n"
 198                 "timeout: Indicates that only data older than 'timeout' seconds is to\n"
 199                 "    be flushed.\n"
 200                 "id: Specifies which values are to be flushed.\n"
 201                 "data: The optional data parameter passed to the register function.\n"
 202                 "    If the parameter was omitted it will be omitted here, too.";
 203
 204 static char reg_shutdown_doc[] = "register_shutdown(callback[, data][, name]) -> identifier\n"
 205                 "\n"
 206                 "Register a callback function for collectd shutdown.\n"
 207                 "'callback' is a callable object that will be called once collectd is\n"
 208                 "    shutting down.\n"
 209                 "'data' is an optional object that will be passed back to the callback\n"
 210                 "    function if it is called.\n"
 211                 "'name' is an optional identifier for this callback. The default name\n"
 212                 "    is 'python.<module>'.\n"
 213                 "    Every callback needs a unique identifier, so if you want to\n"
 214                 "    register this callback multiple time from the same module you need\n"
 215                 "    to specify a name here.\n"
 216                 "'identifier' is the full identifier assigned to this callback.\n"
 217                 "\n"
 218                 "The callback function will be called with no parameters except for\n"
 219                 "    data if it was supplied.";
 220
 221
 222 static int do_interactive = 0;
 223
 224 /* This is our global thread state. Python saves some stuff in thread-local
 225  * storage. So if we allow the interpreter to run in the background
 226  * (the scriptwriters might have created some threads from python), we have
 227  * to save the state so we can resume it later after shutdown. */
 228
 229 static PyThreadState *state;
 230
 231 static PyObject *sys_path, *cpy_format_exception;
 232
 233 static cpy_callback_t *cpy_config_callbacks;
 234 static cpy_callback_t *cpy_init_callbacks;
 235 static cpy_callback_t *cpy_shutdown_callbacks;
 236
 237 static void cpy_destroy_user_data(void *data) {
 238         cpy_callback_t *c = data;
 239         free(c->name);
 240         Py_DECREF(c->callback);
 241         Py_XDECREF(c->data);
 242         free(c);
 243 }
 244
 245 /* You must hold the GIL to call this function!
 246  * But if you managed to extract the callback parameter then you probably already do. */
 247
 248 static void cpy_build_name(char *buf, size_t size, PyObject *callback, const char *name) {
 249         const char *module = NULL;
 250         PyObject *mod = NULL;
 251
 252         if (name != NULL) {
 253                 snprintf(buf, size, "python.%s", name);
 254                 return;
 255         }
 256
 257         mod = PyObject_GetAttrString(callback, "__module__"); /* New reference. */
 258         if (mod != NULL)
 259                 module = cpy_unicode_or_bytes_to_string(&mod);
 260
 261         if (module != NULL) {
 262                 snprintf(buf, size, "python.%s", module);
 263                 Py_XDECREF(mod);
 264                 PyErr_Clear();
 265                 return;
 266         }
 267         Py_XDECREF(mod);
 268
 269         snprintf(buf, size, "python.%p", callback);
 270         PyErr_Clear();
 271 }
 272
 273 void cpy_log_exception(const char *context) {
 274         int l = 0, i;
 275         const char *typename = NULL, *message = NULL;
 276         PyObject *type, *value, *traceback, *tn, *m, *list;
 277
 278         PyErr_Fetch(&type, &value, &traceback);
 279         PyErr_NormalizeException(&type, &value, &traceback);
 280         if (type == NULL) return;
 281         tn = PyObject_GetAttrString(type, "__name__"); /* New reference. */
 282         m = PyObject_Str(value); /* New reference. */
 283         if (tn != NULL)
 284                 typename = cpy_unicode_or_bytes_to_string(&tn);
 285         if (m != NULL)
 286                 message = cpy_unicode_or_bytes_to_string(&m);
 287         if (typename == NULL)
 288                 typename = "NamelessException";
 289         if (message == NULL)
 290                 message = "N/A";
 291         Py_BEGIN_ALLOW_THREADS
 292         ERROR("Unhandled python exception in %s: %s: %s", context, typename, message);
 293         Py_END_ALLOW_THREADS
 294         Py_XDECREF(tn);
 295         Py_XDECREF(m);
 296         if (!cpy_format_exception || !traceback) {
 297                 PyErr_Clear();
 298                 Py_DECREF(type);
 299                 Py_XDECREF(value);
 300                 Py_XDECREF(traceback);
 301                 return;
 302         }
 303         list = PyObject_CallFunction(cpy_format_exception, "NNN", type, value, traceback); /* New reference. Steals references from "type", "value" and "traceback". */
 304         if (list)
 305                 l = PyObject_Length(list);
 306
 307         for (i = 0; i < l; ++i) {
 308                 PyObject *line;
 309                 char const *msg;
 310                 char *cpy;
 311
 312                 line = PyList_GET_ITEM(list, i); /* Borrowed reference. */
 313                 Py_INCREF(line);
 314
 315                 msg = cpy_unicode_or_bytes_to_string(&line);
 316                 Py_DECREF(line);
 317                 if (msg == NULL)
 318                         continue;
 319
 320                 cpy = strdup(msg);
 321                 if (cpy == NULL)
 322                         continue;
 323
 324                 if (cpy[strlen(cpy) - 1] == '\n')
 325                         cpy[strlen(cpy) - 1] = 0;
 326
 327                 Py_BEGIN_ALLOW_THREADS
 328                 ERROR("%s", cpy);
 329                 Py_END_ALLOW_THREADS
 330
 331                 free(cpy);
 332         }
 333
 334         Py_XDECREF(list);
 335         PyErr_Clear();
 336 }
 337
 338 static int cpy_read_callback(user_data_t *data) {
 339         cpy_callback_t *c = data->data;
 340         PyObject *ret;
 341
 342         CPY_LOCK_THREADS
 343                 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
 344                 if (ret == NULL) {
 345                         cpy_log_exception("read callback");
 346                 } else {
 347                         Py_DECREF(ret);
 348                 }
 349         CPY_RELEASE_THREADS
 350         if (ret == NULL)
 351                 return 1;
 352         return 0;
 353 }
 354
 355 static int cpy_write_callback(const data_set_t *ds, const value_list_t *value_list, user_data_t *data) {
 356         size_t i;
 357         cpy_callback_t *c = data->data;
 358         PyObject *ret, *list, *temp, *dict = NULL;
 359         Values *v;
 360
 361         CPY_LOCK_THREADS
 362                 list = PyList_New(value_list->values_len); /* New reference. */
 363                 if (list == NULL) {
 364                         cpy_log_exception("write callback");
 365                         CPY_RETURN_FROM_THREADS 0;
 366                 }
 367                 for (i = 0; i < value_list->values_len; ++i) {
 368                         if (ds->ds[i].type == DS_TYPE_COUNTER) {
 369                                 PyList_SetItem(list, i, PyLong_FromUnsignedLongLong(value_list->values[i].counter));
 370                         } else if (ds->ds[i].type == DS_TYPE_GAUGE) {
 371                                 PyList_SetItem(list, i, PyFloat_FromDouble(value_list->values[i].gauge));
 372                         } else if (ds->ds[i].type == DS_TYPE_DERIVE) {
 373                                 PyList_SetItem(list, i, PyLong_FromLongLong(value_list->values[i].derive));
 374                         } else if (ds->ds[i].type == DS_TYPE_ABSOLUTE) {
 375                                 PyList_SetItem(list, i, PyLong_FromUnsignedLongLong(value_list->values[i].absolute));
 376                         } else {
 377                                 Py_BEGIN_ALLOW_THREADS
 378                                 ERROR("cpy_write_callback: Unknown value type %d.", ds->ds[i].type);
 379                                 Py_END_ALLOW_THREADS
 380                                 Py_DECREF(list);
 381                                 CPY_RETURN_FROM_THREADS 0;
 382                         }
 383                         if (PyErr_Occurred() != NULL) {
 384                                 cpy_log_exception("value building for write callback");
 385                                 Py_DECREF(list);
 386                                 CPY_RETURN_FROM_THREADS 0;
 387                         }
 388                 }
 389                 dict = PyDict_New();  /* New reference. */
 390                 if (value_list->meta) {
 391                         int num;
 392                         char **table;
 393                         meta_data_t *meta = value_list->meta;
 394
 395                         num = meta_data_toc(meta, &table);
 396                         for (i = 0; i < num; ++i) {
 397                                 int type;
 398                                 char *string;
 399                                 int64_t si;
 400                                 uint64_t ui;
 401                                 double d;
 402                                 _Bool b;
 403
 404                                 type = meta_data_type(meta, table[i]);
 405                                 if (type == MD_TYPE_STRING) {
 406                                         if (meta_data_get_string(meta, table[i], &string))
 407                                                 continue;
 408                                         temp = cpy_string_to_unicode_or_bytes(string);  /* New reference. */
 409                                         free(string);
 410                                         PyDict_SetItemString(dict, table[i], temp);
 411                                         Py_XDECREF(temp);
 412                                 } else if (type == MD_TYPE_SIGNED_INT) {
 413                                         if (meta_data_get_signed_int(meta, table[i], &si))
 414                                                 continue;
 415                                         temp = PyObject_CallFunctionObjArgs((void *) &SignedType, PyLong_FromLongLong(si), (void *) 0);  /* New reference. */
 416                                         PyDict_SetItemString(dict, table[i], temp);
 417                                         Py_XDECREF(temp);
 418                                 } else if (type == MD_TYPE_UNSIGNED_INT) {
 419                                         if (meta_data_get_unsigned_int(meta, table[i], &ui))
 420                                                 continue;
 421                                         temp = PyObject_CallFunctionObjArgs((void *) &UnsignedType, PyLong_FromUnsignedLongLong(ui), (void *) 0);  /* New reference. */
 422                                         PyDict_SetItemString(dict, table[i], temp);
 423                                         Py_XDECREF(temp);
 424                                 } else if (type == MD_TYPE_DOUBLE) {
 425                                         if (meta_data_get_double(meta, table[i], &d))
 426                                                 continue;
 427                                         temp = PyFloat_FromDouble(d);  /* New reference. */
 428                                         PyDict_SetItemString(dict, table[i], temp);
 429                                         Py_XDECREF(temp);
 430                                 } else if (type == MD_TYPE_BOOLEAN) {
 431                                         if (meta_data_get_boolean(meta, table[i], &b))
 432                                                 continue;
 433                                         if (b)
 434                                                 PyDict_SetItemString(dict, table[i], Py_True);
 435                                         else
 436                                                 PyDict_SetItemString(dict, table[i], Py_False);
 437                                 }
 438                                 free(table[i]);
 439                         }
 440                         free(table);
 441                 }
 442                 v = (Values *) Values_New(); /* New reference. */
 443                 sstrncpy(v->data.host, value_list->host, sizeof(v->data.host));
 444                 sstrncpy(v->data.type, value_list->type, sizeof(v->data.type));
 445                 sstrncpy(v->data.type_instance, value_list->type_instance, sizeof(v->data.type_instance));
 446                 sstrncpy(v->data.plugin, value_list->plugin, sizeof(v->data.plugin));
 447                 sstrncpy(v->data.plugin_instance, value_list->plugin_instance, sizeof(v->data.plugin_instance));
 448                 v->data.time = CDTIME_T_TO_DOUBLE(value_list->time);
 449                 v->interval = CDTIME_T_TO_DOUBLE(value_list->interval);
 450                 Py_CLEAR(v->values);
 451                 v->values = list;
 452                 Py_CLEAR(v->meta);
 453                 v->meta = dict;  /* Steals a reference. */
 454                 ret = PyObject_CallFunctionObjArgs(c->callback, v, c->data, (void *) 0); /* New reference. */
 455                 Py_XDECREF(v);
 456                 if (ret == NULL) {
 457                         cpy_log_exception("write callback");
 458                 } else {
 459                         Py_DECREF(ret);
 460                 }
 461         CPY_RELEASE_THREADS
 462         return 0;
 463 }
 464
 465 static int cpy_notification_callback(const notification_t *notification, user_data_t *data) {
 466         cpy_callback_t *c = data->data;
 467         PyObject *ret, *notify;
 468         Notification *n;
 469
 470         CPY_LOCK_THREADS
 471                 notify = Notification_New(); /* New reference. */
 472                 n = (Notification *) notify;
 473                 sstrncpy(n->data.host, notification->host, sizeof(n->data.host));
 474                 sstrncpy(n->data.type, notification->type, sizeof(n->data.type));
 475                 sstrncpy(n->data.type_instance, notification->type_instance, sizeof(n->data.type_instance));
 476                 sstrncpy(n->data.plugin, notification->plugin, sizeof(n->data.plugin));
 477                 sstrncpy(n->data.plugin_instance, notification->plugin_instance, sizeof(n->data.plugin_instance));
 478                 n->data.time = CDTIME_T_TO_DOUBLE(notification->time);
 479                 sstrncpy(n->message, notification->message, sizeof(n->message));
 480                 n->severity = notification->severity;
 481                 ret = PyObject_CallFunctionObjArgs(c->callback, n, c->data, (void *) 0); /* New reference. */
 482                 Py_XDECREF(notify);
 483                 if (ret == NULL) {
 484                         cpy_log_exception("notification callback");
 485                 } else {
 486                         Py_DECREF(ret);
 487                 }
 488         CPY_RELEASE_THREADS
 489         return 0;
 490 }
 491
 492 static void cpy_log_callback(int severity, const char *message, user_data_t *data) {
 493         cpy_callback_t * c = data->data;
 494         PyObject *ret, *text;
 495
 496         CPY_LOCK_THREADS
 497         text = cpy_string_to_unicode_or_bytes(message);  /* New reference. */
 498         if (c->data == NULL)
 499                 ret = PyObject_CallFunction(c->callback, "iN", severity, text); /* New reference. Steals a reference from "text". */
 500         else
 501                 ret = PyObject_CallFunction(c->callback, "iNO", severity, text, c->data); /* New reference. Steals a reference from "text". */
 502
 503         if (ret == NULL) {
 504                 /* FIXME */
 505                 /* Do we really want to trigger a log callback because a log callback failed?
 506                  * Probably not. */
 507                 PyErr_Print();
 508                 /* In case someone wanted to be clever, replaced stderr and failed at that. */
 509                 PyErr_Clear();
 510         } else {
 511                 Py_DECREF(ret);
 512         }
 513         CPY_RELEASE_THREADS
 514 }
 515
 516 static void cpy_flush_callback(int timeout, const char *id, user_data_t *data) {
 517         cpy_callback_t * c = data->data;
 518         PyObject *ret, *text;
 519
 520         CPY_LOCK_THREADS
 521         text = cpy_string_to_unicode_or_bytes(id);
 522         if (c->data == NULL)
 523                 ret = PyObject_CallFunction(c->callback, "iN", timeout, text); /* New reference. */
 524         else
 525                 ret = PyObject_CallFunction(c->callback, "iNO", timeout, text, c->data); /* New reference. */
 526
 527         if (ret == NULL) {
 528                 cpy_log_exception("flush callback");
 529         } else {
 530                 Py_DECREF(ret);
 531         }
 532         CPY_RELEASE_THREADS
 533 }
 534
 535 static PyObject *cpy_register_generic(cpy_callback_t **list_head, PyObject *args, PyObject *kwds) {
 536         char buf[512];
 537         cpy_callback_t *c;
 538         char *name = NULL;
 539         PyObject *callback = NULL, *data = NULL, *mod = NULL;
 540         static char *kwlist[] = {"callback", "data", "name", NULL};
 541
 542         if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oet", kwlist, &callback, &data, NULL, &name) == 0) return NULL;
 543         if (PyCallable_Check(callback) == 0) {
 544                 PyMem_Free(name);
 545                 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
 546                 return NULL;
 547         }
 548         cpy_build_name(buf, sizeof(buf), callback, name);
 549
 550         Py_INCREF(callback);
 551         Py_XINCREF(data);
 552
 553         c = calloc(1, sizeof(*c));
 554         if (c == NULL)
 555                 return NULL;
 556
 557         c->name = strdup(buf);
 558         c->callback = callback;
 559         c->data = data;
 560         c->next = *list_head;
 561         *list_head = c;
 562         Py_XDECREF(mod);
 563         PyMem_Free(name);
 564         return cpy_string_to_unicode_or_bytes(buf);
 565 }
 566
 567 static PyObject *float_or_none(float number) {
 568         if (isnan(number)) {
 569                 Py_RETURN_NONE;
 570         }
 571         return PyFloat_FromDouble(number);
 572 }
 573
 574 static PyObject *cpy_get_dataset(PyObject *self, PyObject *args) {
 575         size_t i;
 576         char *name;
 577         const data_set_t *ds;
 578         PyObject *list, *tuple;
 579
 580         if (PyArg_ParseTuple(args, "et", NULL, &name) == 0) return NULL;
 581         ds = plugin_get_ds(name);
 582         PyMem_Free(name);
 583         if (ds == NULL) {
 584                 PyErr_Format(PyExc_TypeError, "Dataset %s not found", name);
 585                 return NULL;
 586         }
 587         list = PyList_New(ds->ds_num); /* New reference. */
 588         for (i = 0; i < ds->ds_num; ++i) {
 589                 tuple = PyTuple_New(4);
 590                 PyTuple_SET_ITEM(tuple, 0, cpy_string_to_unicode_or_bytes(ds->ds[i].name));
 591                 PyTuple_SET_ITEM(tuple, 1, cpy_string_to_unicode_or_bytes(DS_TYPE_TO_STRING(ds->ds[i].type)));
 592                 PyTuple_SET_ITEM(tuple, 2, float_or_none(ds->ds[i].min));
 593                 PyTuple_SET_ITEM(tuple, 3, float_or_none(ds->ds[i].max));
 594                 PyList_SET_ITEM(list, i, tuple);
 595         }
 596         return list;
 597 }
 598
 599 static PyObject *cpy_flush(PyObject *self, PyObject *args, PyObject *kwds) {
 600         int timeout = -1;
 601         char *plugin = NULL, *identifier = NULL;
 602         static char *kwlist[] = {"plugin", "timeout", "identifier", NULL};
 603
 604         if (PyArg_ParseTupleAndKeywords(args, kwds, "|etiet", kwlist, NULL, &plugin, &timeout, NULL, &identifier) == 0) return NULL;
 605         Py_BEGIN_ALLOW_THREADS
 606         plugin_flush(plugin, timeout, identifier);
 607         Py_END_ALLOW_THREADS
 608         PyMem_Free(plugin);
 609         PyMem_Free(identifier);
 610         Py_RETURN_NONE;
 611 }
 612
 613 static PyObject *cpy_register_config(PyObject *self, PyObject *args, PyObject *kwds) {
 614         return cpy_register_generic(&cpy_config_callbacks, args, kwds);
 615 }
 616
 617 static PyObject *cpy_register_init(PyObject *self, PyObject *args, PyObject *kwds) {
 618         return cpy_register_generic(&cpy_init_callbacks, args, kwds);
 619 }
 620
 621 typedef int reg_function_t(const char *name, void *callback, void *data);
 622
 623 static PyObject *cpy_register_generic_userdata(void *reg, void *handler, PyObject *args, PyObject *kwds) {
 624         char buf[512];
 625         reg_function_t *register_function = (reg_function_t *) reg;
 626         cpy_callback_t *c = NULL;
 627         user_data_t user_data = { 0 };
 628         char *name = NULL;
 629         PyObject *callback = NULL, *data = NULL;
 630         static char *kwlist[] = {"callback", "data", "name", NULL};
 631
 632         if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oet", kwlist, &callback, &data, NULL, &name) == 0) return NULL;
 633         if (PyCallable_Check(callback) == 0) {
 634                 PyMem_Free(name);
 635                 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
 636                 return NULL;
 637         }
 638         cpy_build_name(buf, sizeof(buf), callback, name);
 639         PyMem_Free(name);
 640
 641         Py_INCREF(callback);
 642         Py_XINCREF(data);
 643
 644         c = calloc(1, sizeof(*c));
 645         if (c == NULL)
 646                 return NULL;
 647
 648         c->name = strdup(buf);
 649         c->callback = callback;
 650         c->data = data;
 651         c->next = NULL;
 652
 653         user_data.free_func = cpy_destroy_user_data;
 654         user_data.data = c;
 655
 656         register_function(buf, handler, &user_data);
 657         return cpy_string_to_unicode_or_bytes(buf);
 658 }
 659
 660 static PyObject *cpy_register_read(PyObject *self, PyObject *args, PyObject *kwds) {
 661         char buf[512];
 662         cpy_callback_t *c = NULL;
 663         user_data_t user_data = { 0 };
 664         double interval = 0;
 665         char *name = NULL;
 666         PyObject *callback = NULL, *data = NULL;
 667         static char *kwlist[] = {"callback", "interval", "data", "name", NULL};
 668
 669         if (PyArg_ParseTupleAndKeywords(args, kwds, "O|dOet", kwlist, &callback, &interval, &data, NULL, &name) == 0) return NULL;
 670         if (PyCallable_Check(callback) == 0) {
 671                 PyMem_Free(name);
 672                 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
 673                 return NULL;
 674         }
 675         cpy_build_name(buf, sizeof(buf), callback, name);
 676         PyMem_Free(name);
 677
 678         Py_INCREF(callback);
 679         Py_XINCREF(data);
 680
 681         c = calloc(1, sizeof(*c));
 682         if (c == NULL)
 683                 return NULL;
 684
 685         c->name = strdup(buf);
 686         c->callback = callback;
 687         c->data = data;
 688         c->next = NULL;
 689
 690         user_data.free_func = cpy_destroy_user_data;
 691         user_data.data = c;
 692
 693         plugin_register_complex_read(/* group = */ "python", buf,
 694                         cpy_read_callback, DOUBLE_TO_CDTIME_T (interval), &user_data);
 695         return cpy_string_to_unicode_or_bytes(buf);
 696 }
 697
 698 static PyObject *cpy_register_log(PyObject *self, PyObject *args, PyObject *kwds) {
 699         return cpy_register_generic_userdata((void *) plugin_register_log,
 700                         (void *) cpy_log_callback, args, kwds);
 701 }
 702
 703 static PyObject *cpy_register_write(PyObject *self, PyObject *args, PyObject *kwds) {
 704         return cpy_register_generic_userdata((void *) plugin_register_write,
 705                         (void *) cpy_write_callback, args, kwds);
 706 }
 707
 708 static PyObject *cpy_register_notification(PyObject *self, PyObject *args, PyObject *kwds) {
 709         return cpy_register_generic_userdata((void *) plugin_register_notification,
 710                         (void *) cpy_notification_callback, args, kwds);
 711 }
 712
 713 static PyObject *cpy_register_flush(PyObject *self, PyObject *args, PyObject *kwds) {
 714         return cpy_register_generic_userdata((void *) plugin_register_flush,
 715                         (void *) cpy_flush_callback, args, kwds);
 716 }
 717
 718 static PyObject *cpy_register_shutdown(PyObject *self, PyObject *args, PyObject *kwds) {
 719         return cpy_register_generic(&cpy_shutdown_callbacks, args, kwds);
 720 }
 721
 722 static PyObject *cpy_error(PyObject *self, PyObject *args) {
 723         char *text;
 724         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 725         Py_BEGIN_ALLOW_THREADS
 726         plugin_log(LOG_ERR, "%s", text);
 727         Py_END_ALLOW_THREADS
 728         PyMem_Free(text);
 729         Py_RETURN_NONE;
 730 }
 731
 732 static PyObject *cpy_warning(PyObject *self, PyObject *args) {
 733         char *text;
 734         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 735         Py_BEGIN_ALLOW_THREADS
 736         plugin_log(LOG_WARNING, "%s", text);
 737         Py_END_ALLOW_THREADS
 738         PyMem_Free(text);
 739         Py_RETURN_NONE;
 740 }
 741
 742 static PyObject *cpy_notice(PyObject *self, PyObject *args) {
 743         char *text;
 744         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 745         Py_BEGIN_ALLOW_THREADS
 746         plugin_log(LOG_NOTICE, "%s", text);
 747         Py_END_ALLOW_THREADS
 748         PyMem_Free(text);
 749         Py_RETURN_NONE;
 750 }
 751
 752 static PyObject *cpy_info(PyObject *self, PyObject *args) {
 753         char *text;
 754         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 755         Py_BEGIN_ALLOW_THREADS
 756         plugin_log(LOG_INFO, "%s", text);
 757         Py_END_ALLOW_THREADS
 758         PyMem_Free(text);
 759         Py_RETURN_NONE;
 760 }
 761
 762 static PyObject *cpy_debug(PyObject *self, PyObject *args) {
 763 #ifdef COLLECT_DEBUG
 764         char *text;
 765         if (PyArg_ParseTuple(args, "et", NULL, &text) == 0) return NULL;
 766         Py_BEGIN_ALLOW_THREADS
 767         plugin_log(LOG_DEBUG, "%s", text);
 768         Py_END_ALLOW_THREADS
 769         PyMem_Free(text);
 770 #endif
 771         Py_RETURN_NONE;
 772 }
 773
 774 static PyObject *cpy_unregister_generic(cpy_callback_t **list_head, PyObject *arg, const char *desc) {
 775         char buf[512];
 776         const char *name;
 777         cpy_callback_t *prev = NULL, *tmp;
 778
 779         Py_INCREF(arg);
 780         name = cpy_unicode_or_bytes_to_string(&arg);
 781         if (name == NULL) {
 782                 PyErr_Clear();
 783                 if (!PyCallable_Check(arg)) {
 784                         PyErr_SetString(PyExc_TypeError, "This function needs a string or a callable object as its only parameter.");
 785                         Py_DECREF(arg);
 786                         return NULL;
 787                 }
 788                 cpy_build_name(buf, sizeof(buf), arg, NULL);
 789                 name = buf;
 790         }
 791         for (tmp = *list_head; tmp; prev = tmp, tmp = tmp->next)
 792                 if (strcmp(name, tmp->name) == 0)
 793                         break;
 794
 795         Py_DECREF(arg);
 796         if (tmp == NULL) {
 797                 PyErr_Format(PyExc_RuntimeError, "Unable to unregister %s callback '%s'.", desc, name);
 798                 return NULL;
 799         }
 800         /* Yes, this is actually save. To call this function the caller has to
 801          * hold the GIL. Well, save as long as there is only one GIL anyway ... */
 802         if (prev == NULL)
 803                 *list_head = tmp->next;
 804         else
 805                 prev->next = tmp->next;
 806         cpy_destroy_user_data(tmp);
 807         Py_RETURN_NONE;
 808 }
 809
 810 typedef int cpy_unregister_function_t(const char *name);
 811
 812 static PyObject *cpy_unregister_generic_userdata(cpy_unregister_function_t *unreg, PyObject *arg, const char *desc) {
 813         char buf[512];
 814         const char *name;
 815
 816         Py_INCREF(arg);
 817         name = cpy_unicode_or_bytes_to_string(&arg);
 818         if (name == NULL) {
 819                 PyErr_Clear();
 820                 if (!PyCallable_Check(arg)) {
 821                         PyErr_SetString(PyExc_TypeError, "This function needs a string or a callable object as its only parameter.");
 822                         Py_DECREF(arg);
 823                         return NULL;
 824                 }
 825                 cpy_build_name(buf, sizeof(buf), arg, NULL);
 826                 name = buf;
 827         }
 828         if (unreg(name) == 0) {
 829                 Py_DECREF(arg);
 830                 Py_RETURN_NONE;
 831         }
 832         PyErr_Format(PyExc_RuntimeError, "Unable to unregister %s callback '%s'.", desc, name);
 833         Py_DECREF(arg);
 834         return NULL;
 835 }
 836
 837 static PyObject *cpy_unregister_log(PyObject *self, PyObject *arg) {
 838         return cpy_unregister_generic_userdata(plugin_unregister_log, arg, "log");
 839 }
 840
 841 static PyObject *cpy_unregister_init(PyObject *self, PyObject *arg) {
 842         return cpy_unregister_generic(&cpy_init_callbacks, arg, "init");
 843 }
 844
 845 static PyObject *cpy_unregister_config(PyObject *self, PyObject *arg) {
 846         return cpy_unregister_generic(&cpy_config_callbacks, arg, "config");
 847 }
 848
 849 static PyObject *cpy_unregister_read(PyObject *self, PyObject *arg) {
 850         return cpy_unregister_generic_userdata(plugin_unregister_read, arg, "read");
 851 }
 852
 853 static PyObject *cpy_unregister_write(PyObject *self, PyObject *arg) {
 854         return cpy_unregister_generic_userdata(plugin_unregister_write, arg, "write");
 855 }
 856
 857 static PyObject *cpy_unregister_notification(PyObject *self, PyObject *arg) {
 858         return cpy_unregister_generic_userdata(plugin_unregister_notification, arg, "notification");
 859 }
 860
 861 static PyObject *cpy_unregister_flush(PyObject *self, PyObject *arg) {
 862         return cpy_unregister_generic_userdata(plugin_unregister_flush, arg, "flush");
 863 }
 864
 865 static PyObject *cpy_unregister_shutdown(PyObject *self, PyObject *arg) {
 866         return cpy_unregister_generic(&cpy_shutdown_callbacks, arg, "shutdown");
 867 }
 868
 869 static PyMethodDef cpy_methods[] = {
 870         {"debug", cpy_debug, METH_VARARGS, log_doc},
 871         {"info", cpy_info, METH_VARARGS, log_doc},
 872         {"notice", cpy_notice, METH_VARARGS, log_doc},
 873         {"warning", cpy_warning, METH_VARARGS, log_doc},
 874         {"error", cpy_error, METH_VARARGS, log_doc},
 875         {"get_dataset", (PyCFunction) cpy_get_dataset, METH_VARARGS, get_ds_doc},
 876         {"flush", (PyCFunction) cpy_flush, METH_VARARGS | METH_KEYWORDS, flush_doc},
 877         {"register_log", (PyCFunction) cpy_register_log, METH_VARARGS | METH_KEYWORDS, reg_log_doc},
 878         {"register_init", (PyCFunction) cpy_register_init, METH_VARARGS | METH_KEYWORDS, reg_init_doc},
 879         {"register_config", (PyCFunction) cpy_register_config, METH_VARARGS | METH_KEYWORDS, reg_config_doc},
 880         {"register_read", (PyCFunction) cpy_register_read, METH_VARARGS | METH_KEYWORDS, reg_read_doc},
 881         {"register_write", (PyCFunction) cpy_register_write, METH_VARARGS | METH_KEYWORDS, reg_write_doc},
 882         {"register_notification", (PyCFunction) cpy_register_notification, METH_VARARGS | METH_KEYWORDS, reg_notification_doc},
 883         {"register_flush", (PyCFunction) cpy_register_flush, METH_VARARGS | METH_KEYWORDS, reg_flush_doc},
 884         {"register_shutdown", (PyCFunction) cpy_register_shutdown, METH_VARARGS | METH_KEYWORDS, reg_shutdown_doc},
 885         {"unregister_log", cpy_unregister_log, METH_O, unregister_doc},
 886         {"unregister_init", cpy_unregister_init, METH_O, unregister_doc},
 887         {"unregister_config", cpy_unregister_config, METH_O, unregister_doc},
 888         {"unregister_read", cpy_unregister_read, METH_O, unregister_doc},
 889         {"unregister_write", cpy_unregister_write, METH_O, unregister_doc},
 890         {"unregister_notification", cpy_unregister_notification, METH_O, unregister_doc},
 891         {"unregister_flush", cpy_unregister_flush, METH_O, unregister_doc},
 892         {"unregister_shutdown", cpy_unregister_shutdown, METH_O, unregister_doc},
 893         {0, 0, 0, 0}
 894 };
 895
 896 static int cpy_shutdown(void) {
 897         cpy_callback_t *c;
 898         PyObject *ret;
 899
 900         /* This can happen if the module was loaded but not configured. */
 901         if (state != NULL)
 902                 PyEval_RestoreThread(state);
 903
 904         for (c = cpy_shutdown_callbacks; c; c = c->next) {
 905                 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
 906                 if (ret == NULL)
 907                         cpy_log_exception("shutdown callback");
 908                 else
 909                         Py_DECREF(ret);
 910         }
 911         PyErr_Print();
 912         Py_Finalize();
 913         return 0;
 914 }
 915
 916 static void cpy_int_handler(int sig) {
 917         return;
 918 }
 919
 920 static void *cpy_interactive(void *data) {
 921         sigset_t sigset;
 922         struct sigaction old;
 923
 924         /* Signal handler in a plugin? Bad stuff, but the best way to
 925          * handle it I guess. In an interactive session people will
 926          * press Ctrl+C at some time, which will generate a SIGINT.
 927          * This will cause collectd to shutdown, thus killing the
 928          * interactive interpreter, and leaving the terminal in a
 929          * mess. Chances are, this isn't what the user wanted to do.
 930          *
 931          * So this is the plan:
 932          * 1. Block SIGINT in the main thread.
 933          * 2. Install our own signal handler that does nothing.
 934          * 3. Unblock SIGINT in the interactive thread.
 935          *
 936          * This will make sure that SIGINT won't kill collectd but
 937          * still interrupt syscalls like sleep and pause.
 938          * It does not raise a KeyboardInterrupt exception because so
 939          * far nobody managed to figure out how to do that. */
 940         struct sigaction sig_int_action = {
 941                 .sa_handler = cpy_int_handler
 942         };
 943         sigaction (SIGINT, &sig_int_action, &old);
 944
 945         sigemptyset(&sigset);
 946         sigaddset(&sigset, SIGINT);
 947         pthread_sigmask(SIG_UNBLOCK, &sigset, NULL);
 948         PyEval_AcquireThread(state);
 949         if (PyImport_ImportModule("readline") == NULL) {
 950                 /* This interactive session will suck. */
 951                 cpy_log_exception("interactive session init");
 952         }
 953         PyRun_InteractiveLoop(stdin, "<stdin>");
 954         PyErr_Print();
 955         PyEval_ReleaseThread(state);
 956         NOTICE("python: Interactive interpreter exited, stopping collectd ...");
 957         /* Restore the original collectd SIGINT handler and raise SIGINT.
 958          * The main thread still has SIGINT blocked and there's nothing we
 959          * can do about that so this thread will handle it. But that's not
 960          * important, except that it won't interrupt the main loop and so
 961          * it might take a few seconds before collectd really shuts down. */
 962         sigaction (SIGINT, &old, NULL);
 963         raise(SIGINT);
 964         pause();
 965         return NULL;
 966 }
 967
 968 static int cpy_init(void) {
 969         cpy_callback_t *c;
 970         PyObject *ret;
 971         static pthread_t thread;
 972         sigset_t sigset;
 973
 974         if (!Py_IsInitialized()) {
 975                 WARNING("python: Plugin loaded but not configured.");
 976                 plugin_unregister_shutdown("python");
 977                 return 0;
 978         }
 979         PyEval_InitThreads();
 980         /* Now it's finally OK to use python threads. */
 981         for (c = cpy_init_callbacks; c; c = c->next) {
 982                 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
 983                 if (ret == NULL)
 984                         cpy_log_exception("init callback");
 985                 else
 986                         Py_DECREF(ret);
 987         }
 988         sigemptyset(&sigset);
 989         sigaddset(&sigset, SIGINT);
 990         pthread_sigmask(SIG_BLOCK, &sigset, NULL);
 991         state = PyEval_SaveThread();
 992         if (do_interactive) {
 993                 if (plugin_thread_create(&thread, NULL, cpy_interactive, NULL)) {
 994                         ERROR("python: Error creating thread for interactive interpreter.");
 995                 }
 996         }
 997
 998         return 0;
 999 }
1000
1001 static PyObject *cpy_oconfig_to_pyconfig(oconfig_item_t *ci, PyObject *parent) {
1002         int i;
1003         PyObject *item, *values, *children, *tmp;
1004
1005         if (parent == NULL)
1006                 parent = Py_None;
1007
1008         values = PyTuple_New(ci->values_num); /* New reference. */
1009         for (i = 0; i < ci->values_num; ++i) {
1010                 if (ci->values[i].type == OCONFIG_TYPE_STRING) {
1011                         PyTuple_SET_ITEM(values, i, cpy_string_to_unicode_or_bytes(ci->values[i].value.string));
1012                 } else if (ci->values[i].type == OCONFIG_TYPE_NUMBER) {
1013                         PyTuple_SET_ITEM(values, i, PyFloat_FromDouble(ci->values[i].value.number));
1014                 } else if (ci->values[i].type == OCONFIG_TYPE_BOOLEAN) {
1015                         PyTuple_SET_ITEM(values, i, PyBool_FromLong(ci->values[i].value.boolean));
1016                 }
1017         }
1018
1019         tmp = cpy_string_to_unicode_or_bytes(ci->key);
1020         item = PyObject_CallFunction((void *) &ConfigType, "NONO", tmp, parent, values, Py_None);
1021         if (item == NULL)
1022                 return NULL;
1023         children = PyTuple_New(ci->children_num); /* New reference. */
1024         for (i = 0; i < ci->children_num; ++i) {
1025                 PyTuple_SET_ITEM(children, i, cpy_oconfig_to_pyconfig(ci->children + i, item));
1026         }
1027         tmp = ((Config *) item)->children;
1028         ((Config *) item)->children = children;
1029         Py_XDECREF(tmp);
1030         return item;
1031 }
1032
1033 #ifdef IS_PY3K
1034 static struct PyModuleDef collectdmodule = {
1035         PyModuleDef_HEAD_INIT,
1036         "collectd",   /* name of module */
1037         "The python interface to collectd", /* module documentation, may be NULL */
1038         -1,
1039         cpy_methods
1040 };
1041
1042 PyMODINIT_FUNC PyInit_collectd(void) {
1043         return PyModule_Create(&collectdmodule);
1044 }
1045 #endif
1046
1047 static int cpy_init_python(void) {
1048         PyObject *sys;
1049         PyObject *module;
1050
1051 #ifdef IS_PY3K
1052         wchar_t *argv = L"";
1053         /* Add a builtin module, before Py_Initialize */
1054         PyImport_AppendInittab("collectd", PyInit_collectd);
1055 #else
1056         char *argv = "";
1057 #endif
1058
1059         Py_Initialize();
1060
1061         PyType_Ready(&ConfigType);
1062         PyType_Ready(&PluginDataType);
1063         ValuesType.tp_base = &PluginDataType;
1064         PyType_Ready(&ValuesType);
1065         NotificationType.tp_base = &PluginDataType;
1066         PyType_Ready(&NotificationType);
1067         SignedType.tp_base = &PyLong_Type;
1068         PyType_Ready(&SignedType);
1069         UnsignedType.tp_base = &PyLong_Type;
1070         PyType_Ready(&UnsignedType);
1071         sys = PyImport_ImportModule("sys"); /* New reference. */
1072         if (sys == NULL) {
1073                 cpy_log_exception("python initialization");
1074                 return 1;
1075         }
1076         sys_path = PyObject_GetAttrString(sys, "path"); /* New reference. */
1077         Py_DECREF(sys);
1078         if (sys_path == NULL) {
1079                 cpy_log_exception("python initialization");
1080                 return 1;
1081         }
1082         PySys_SetArgv(1, &argv);
1083         PyList_SetSlice(sys_path, 0, 1, NULL);
1084
1085 #ifdef IS_PY3K
1086         module = PyImport_ImportModule("collectd");
1087 #else
1088         module = Py_InitModule("collectd", cpy_methods); /* Borrowed reference. */
1089 #endif
1090         PyModule_AddObject(module, "Config", (void *) &ConfigType); /* Steals a reference. */
1091         PyModule_AddObject(module, "Values", (void *) &ValuesType); /* Steals a reference. */
1092         PyModule_AddObject(module, "Notification", (void *) &NotificationType); /* Steals a reference. */
1093         PyModule_AddObject(module, "Signed", (void *) &SignedType); /* Steals a reference. */
1094         PyModule_AddObject(module, "Unsigned", (void *) &UnsignedType); /* Steals a reference. */
1095         PyModule_AddIntConstant(module, "LOG_DEBUG", LOG_DEBUG);
1096         PyModule_AddIntConstant(module, "LOG_INFO", LOG_INFO);
1097         PyModule_AddIntConstant(module, "LOG_NOTICE", LOG_NOTICE);
1098         PyModule_AddIntConstant(module, "LOG_WARNING", LOG_WARNING);
1099         PyModule_AddIntConstant(module, "LOG_ERROR", LOG_ERR);
1100         PyModule_AddIntConstant(module, "NOTIF_FAILURE", NOTIF_FAILURE);
1101         PyModule_AddIntConstant(module, "NOTIF_WARNING", NOTIF_WARNING);
1102         PyModule_AddIntConstant(module, "NOTIF_OKAY", NOTIF_OKAY);
1103         PyModule_AddStringConstant(module, "DS_TYPE_COUNTER", DS_TYPE_TO_STRING(DS_TYPE_COUNTER));
1104         PyModule_AddStringConstant(module, "DS_TYPE_GAUGE", DS_TYPE_TO_STRING(DS_TYPE_GAUGE));
1105         PyModule_AddStringConstant(module, "DS_TYPE_DERIVE", DS_TYPE_TO_STRING(DS_TYPE_DERIVE));
1106         PyModule_AddStringConstant(module, "DS_TYPE_ABSOLUTE", DS_TYPE_TO_STRING(DS_TYPE_ABSOLUTE));
1107         return 0;
1108 }
1109
1110 static int cpy_config(oconfig_item_t *ci) {
1111         int i;
1112         PyObject *tb;
1113
1114         /* Ok in theory we shouldn't do initialization at this point
1115          * but we have to. In order to give python scripts a chance
1116          * to register a config callback we need to be able to execute
1117          * python code during the config callback so we have to start
1118          * the interpreter here. */
1119         /* Do *not* use the python "thread" module at this point! */
1120
1121         if (!Py_IsInitialized() && cpy_init_python()) return 1;
1122
1123         for (i = 0; i < ci->children_num; ++i) {
1124                 oconfig_item_t *item = ci->children + i;
1125
1126                 if (strcasecmp(item->key, "Interactive") == 0) {
1127                         if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_BOOLEAN)
1128                                 continue;
1129                         do_interactive = item->values[0].value.boolean;
1130                 } else if (strcasecmp(item->key, "Encoding") == 0) {
1131                         if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_STRING)
1132                                 continue;
1133 #ifdef IS_PY3K
1134                         NOTICE("python: \"Encoding\" was used in the config file but Python3 was used, which does not support changing encodings. Ignoring this.");
1135 #else
1136                         /* Why is this even necessary? And undocumented? */
1137                         if (PyUnicode_SetDefaultEncoding(item->values[0].value.string))
1138                                 cpy_log_exception("setting default encoding");
1139 #endif
1140                 } else if (strcasecmp(item->key, "LogTraces") == 0) {
1141                         if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_BOOLEAN)
1142                                 continue;
1143                         if (!item->values[0].value.boolean) {
1144                                 Py_XDECREF(cpy_format_exception);
1145                                 cpy_format_exception = NULL;
1146                                 continue;
1147                         }
1148                         if (cpy_format_exception)
1149                                 continue;
1150                         tb = PyImport_ImportModule("traceback"); /* New reference. */
1151                         if (tb == NULL) {
1152                                 cpy_log_exception("python initialization");
1153                                 continue;
1154                         }
1155                         cpy_format_exception = PyObject_GetAttrString(tb, "format_exception"); /* New reference. */
1156                         Py_DECREF(tb);
1157                         if (cpy_format_exception == NULL)
1158                                 cpy_log_exception("python initialization");
1159                 } else if (strcasecmp(item->key, "ModulePath") == 0) {
1160                         char *dir = NULL;
1161                         PyObject *dir_object;
1162
1163                         if (cf_util_get_string(item, &dir) != 0)
1164                                 continue;
1165                         dir_object = cpy_string_to_unicode_or_bytes(dir); /* New reference. */
1166                         if (dir_object == NULL) {
1167                                 ERROR("python plugin: Unable to convert \"%s\" to "
1168                                       "a python object.", dir);
1169                                 free(dir);
1170                                 cpy_log_exception("python initialization");
1171                                 continue;
1172                         }
1173                         if (PyList_Insert(sys_path, 0, dir_object) != 0) {
1174                                 ERROR("python plugin: Unable to prepend \"%s\" to "
1175                                       "python module path.", dir);
1176                                 cpy_log_exception("python initialization");
1177                         }
1178                         Py_DECREF(dir_object);
1179                         free(dir);
1180                 } else if (strcasecmp(item->key, "Import") == 0) {
1181                         char *module_name = NULL;
1182                         PyObject *module;
1183
1184                         if (cf_util_get_string(item, &module_name) != 0)
1185                                 continue;
1186                         module = PyImport_ImportModule(module_name); /* New reference. */
1187                         if (module == NULL) {
1188                                 ERROR("python plugin: Error importing module \"%s\".", module_name);
1189                                 cpy_log_exception("importing module");
1190                         }
1191                         free(module_name);
1192                         Py_XDECREF(module);
1193                 } else if (strcasecmp(item->key, "Module") == 0) {
1194                         char *name = NULL;
1195                         cpy_callback_t *c;
1196                         PyObject *ret;
1197
1198                         if (cf_util_get_string(item, &name) != 0)
1199                                 continue;
1200                         for (c = cpy_config_callbacks; c; c = c->next) {
1201                                 if (strcasecmp(c->name + 7, name) == 0)
1202                                         break;
1203                         }
1204                         if (c == NULL) {
1205                                 WARNING("python plugin: Found a configuration for the \"%s\" plugin, "
1206                                         "but the plugin isn't loaded or didn't register "
1207                                         "a configuration callback.", name);
1208                                 free(name);
1209                                 continue;
1210                         }
1211                         free(name);
1212                         if (c->data == NULL)
1213                                 ret = PyObject_CallFunction(c->callback, "N",
1214                                         cpy_oconfig_to_pyconfig(item, NULL)); /* New reference. */
1215                         else
1216                                 ret = PyObject_CallFunction(c->callback, "NO",
1217                                         cpy_oconfig_to_pyconfig(item, NULL), c->data); /* New reference. */
1218                         if (ret == NULL)
1219                                 cpy_log_exception("loading module");
1220                         else
1221                                 Py_DECREF(ret);
1222                 } else {
1223                         WARNING("python plugin: Ignoring unknown config key \"%s\".", item->key);
1224                 }
1225         }
1226         return 0;
1227 }
1228
1229 void module_register(void) {
1230         plugin_register_complex_config("python", cpy_config);
1231         plugin_register_init("python", cpy_init);
1232         plugin_register_shutdown("python", cpy_shutdown);
1233 }