src/python.c

   1 #include <Python.h>
   2 #include <structmember.h>
   3
   4 #if HAVE_PTHREAD_H
   5 # include <pthread.h>
   6 #endif
   7
   8 #include "collectd.h"
   9 #include "common.h"
  10
  11 #include "cpython.h"
  12
  13 typedef struct cpy_callback_s {
  14         char *name;
  15         PyObject *callback;
  16         PyObject *data;
  17         struct cpy_callback_s *next;
  18 } cpy_callback_t;
  19
  20 static int do_interactive = 0;
  21
  22 /* This is our global thread state. Python saves some stuff in thread-local
  23  * storage. So if we allow the interpreter to run in the background
  24  * (the scriptwriters might have created some threads from python), we have
  25  * to save the state so we can resume it later after shutdown. */
  26
  27 static PyThreadState *state;
  28
  29 static PyObject *cpy_format_exception;
  30
  31 static cpy_callback_t *cpy_config_callbacks;
  32 static cpy_callback_t *cpy_init_callbacks;
  33 static cpy_callback_t *cpy_shutdown_callbacks;
  34
  35 static void cpy_destroy_user_data(void *data) {
  36         cpy_callback_t *c = data;
  37         free(c->name);
  38         Py_DECREF(c->callback);
  39         Py_XDECREF(c->data);
  40         free(c);
  41 }
  42
  43 /* You must hold the GIL to call this function!
  44  * But if you managed to extract the callback parameter then you probably already do. */
  45
  46 static void cpy_build_name(char *buf, size_t size, PyObject *callback, const char *name, int short_name) {
  47         const char *module;
  48         PyObject *mod = NULL, *n = NULL;
  49
  50         if (name != NULL && (strchr(name, '.') != NULL || short_name)) {
  51                 snprintf(buf, size, "python.%s", name);
  52                 return;
  53         }
  54
  55         mod = PyObject_GetAttrString(callback, "__module__"); /* New reference. */
  56         if (mod != NULL)
  57                 module = PyString_AsString(mod);
  58         else
  59                 module = "collectd";
  60
  61         if (short_name) {
  62                 snprintf(buf, size, "python.%s", module);
  63                 Py_XDECREF(mod);
  64                 return;
  65         }
  66
  67         if (name != NULL) {
  68                 snprintf(buf, size, "python.%s.%s", module, name);
  69                 Py_XDECREF(mod);
  70                 return;
  71         }
  72
  73         n = PyObject_GetAttrString(callback, "__name__"); /* New reference. */
  74         if (n != NULL)
  75                 name = PyString_AsString(n);
  76
  77         if (name != NULL)
  78                 snprintf(buf, size, "python.%s.%s", module, name);
  79         else
  80                 snprintf(buf, size, "python.%s.%p", module, callback);
  81         Py_XDECREF(mod);
  82         Py_XDECREF(n);
  83 }
  84
  85 static void cpy_log_exception(const char *context) {
  86         int l = 0, i;
  87         const char *typename = NULL, *message = NULL;
  88         PyObject *type, *value, *traceback, *tn, *m, *list;
  89
  90         PyErr_Fetch(&type, &value, &traceback);
  91         PyErr_NormalizeException(&type, &value, &traceback);
  92         if (type == NULL) return;
  93         tn = PyObject_GetAttrString(type, "__name__"); /* New reference. */
  94         m = PyObject_GetAttrString(value, "message"); /* New reference. */
  95         if (tn != NULL)
  96                 typename = PyString_AsString(tn);
  97         if (m != NULL)
  98                 message = PyString_AsString(m);
  99         if (typename == NULL)
 100                 typename = "NamelessException";
 101         if (message == NULL)
 102                 message = "N/A";
 103         ERROR("Unhandled python exception in %s: %s: %s", context, typename, message);
 104         Py_XDECREF(tn);
 105         Py_XDECREF(m);
 106         if (!cpy_format_exception) {
 107                 PyErr_Clear();
 108                 Py_XDECREF(type);
 109                 Py_XDECREF(value);
 110                 Py_XDECREF(traceback);
 111                 return;
 112         }
 113         if (!traceback) {
 114                 PyErr_Clear();
 115                 return;
 116         }
 117         list = PyObject_CallFunction(cpy_format_exception, "NNN", type, value, traceback);
 118         if (list)
 119                 l = PyObject_Length(list);
 120         for (i = 0; i < l; ++i) {
 121                 char *s;
 122                 PyObject *line;
 123
 124                 line = PyList_GET_ITEM(list, i);
 125                 s = strdup(PyString_AsString(line));
 126                 Py_DECREF(line);
 127                 if (s[strlen(s) - 1] == '\n')
 128                         s[strlen(s) - 1] = 0;
 129                 ERROR("%s", s);
 130                 free(s);
 131         }
 132         PyErr_Clear();
 133 }
 134
 135 static int cpy_read_callback(user_data_t *data) {
 136         cpy_callback_t *c = data->data;
 137         PyObject *ret;
 138
 139         CPY_LOCK_THREADS
 140                 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
 141                 if (ret == NULL) {
 142                         cpy_log_exception("read callback");
 143                 } else {
 144                         Py_DECREF(ret);
 145                 }
 146         CPY_RELEASE_THREADS
 147         return 0;
 148 }
 149
 150 static int cpy_write_callback(const data_set_t *ds, const value_list_t *value_list, user_data_t *data) {
 151         int i;
 152         cpy_callback_t *c = data->data;
 153         PyObject *ret, *v, *list;
 154
 155         CPY_LOCK_THREADS
 156                 list = PyList_New(value_list->values_len); /* New reference. */
 157                 if (list == NULL) {
 158                         cpy_log_exception("write callback");
 159                         CPY_RETURN_FROM_THREADS 0;
 160                 }
 161                 for (i = 0; i < value_list->values_len; ++i) {
 162                         if (ds->ds->type == DS_TYPE_COUNTER) {
 163                                 if ((long) value_list->values[i].counter == value_list->values[i].counter)
 164                                         PyList_SetItem(list, i, PyInt_FromLong(value_list->values[i].counter));
 165                                 else
 166                                         PyList_SetItem(list, i, PyLong_FromUnsignedLongLong(value_list->values[i].counter));
 167                         } else if (ds->ds->type == DS_TYPE_GAUGE) {
 168                                 PyList_SetItem(list, i, PyFloat_FromDouble(value_list->values[i].gauge));
 169                         } else if (ds->ds->type == DS_TYPE_DERIVE) {
 170                                 if ((long) value_list->values[i].derive == value_list->values[i].derive)
 171                                         PyList_SetItem(list, i, PyInt_FromLong(value_list->values[i].derive));
 172                                 else
 173                                         PyList_SetItem(list, i, PyLong_FromLongLong(value_list->values[i].derive));
 174                         } else if (ds->ds->type == DS_TYPE_ABSOLUTE) {
 175                                 if ((long) value_list->values[i].absolute == value_list->values[i].absolute)
 176                                         PyList_SetItem(list, i, PyInt_FromLong(value_list->values[i].absolute));
 177                                 else
 178                                         PyList_SetItem(list, i, PyLong_FromUnsignedLongLong(value_list->values[i].absolute));
 179                         } else {
 180                                 ERROR("cpy_write_callback: Unknown value type %d.", ds->ds->type);
 181                                 Py_DECREF(list);
 182                                 CPY_RETURN_FROM_THREADS 0;
 183                         }
 184                         if (PyErr_Occurred() != NULL) {
 185                                 cpy_log_exception("value building for write callback");
 186                                 CPY_RETURN_FROM_THREADS 0;
 187                         }
 188                 }
 189                 v = PyObject_CallFunction((PyObject *) &ValuesType, "sOssssdi", value_list->type, list,
 190                                 value_list->plugin_instance, value_list->type_instance, value_list->plugin,
 191                                 value_list->host, (double) value_list->time, value_list->interval);
 192                 Py_DECREF(list);
 193                 ret = PyObject_CallFunctionObjArgs(c->callback, v, c->data, (void *) 0); /* New reference. */
 194                 if (ret == NULL) {
 195                         cpy_log_exception("write callback");
 196                 } else {
 197                         Py_DECREF(ret);
 198                 }
 199         CPY_RELEASE_THREADS
 200         return 0;
 201 }
 202
 203 static void cpy_log_callback(int severity, const char *message, user_data_t *data) {
 204         cpy_callback_t * c = data->data;
 205         PyObject *ret;
 206
 207         CPY_LOCK_THREADS
 208         if (c->data == NULL)
 209                 ret = PyObject_CallFunction(c->callback, "is", severity, message); /* New reference. */
 210         else
 211                 ret = PyObject_CallFunction(c->callback, "isO", severity, message, c->data); /* New reference. */
 212
 213         if (ret == NULL) {
 214                 /* FIXME */
 215                 /* Do we really want to trigger a log callback because a log callback failed?
 216                  * Probably not. */
 217                 PyErr_Print();
 218         } else {
 219                 Py_DECREF(ret);
 220         }
 221         CPY_RELEASE_THREADS
 222 }
 223
 224 static void cpy_flush_callback(int timeout, const char *id, user_data_t *data) {
 225         cpy_callback_t * c = data->data;
 226         PyObject *ret;
 227
 228         CPY_LOCK_THREADS
 229         if (c->data == NULL)
 230                 ret = PyObject_CallFunction(c->callback, "is", timeout, id); /* New reference. */
 231         else
 232                 ret = PyObject_CallFunction(c->callback, "isO", timeout, id, c->data); /* New reference. */
 233
 234         if (ret == NULL) {
 235                 cpy_log_exception("flush callback");
 236         } else {
 237                 Py_DECREF(ret);
 238         }
 239         CPY_RELEASE_THREADS
 240 }
 241
 242 static PyObject *cpy_register_generic(cpy_callback_t **list_head, PyObject *args, PyObject *kwds, int short_name) {
 243         char buf[512];
 244         cpy_callback_t *c;
 245         const char *name = NULL;
 246         PyObject *callback = NULL, *data = NULL, *mod = NULL;
 247         static char *kwlist[] = {"callback", "data", "name", NULL};
 248
 249         if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oz", kwlist, &callback, &data, &name) == 0) return NULL;
 250         if (PyCallable_Check(callback) == 0) {
 251                 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
 252                 return NULL;
 253         }
 254         cpy_build_name(buf, sizeof(buf), callback, name, short_name);
 255
 256         Py_INCREF(callback);
 257         Py_XINCREF(data);
 258         c = malloc(sizeof(*c));
 259         c->name = strdup(buf);
 260         c->callback = callback;
 261         c->data = data;
 262         c->next = *list_head;
 263         *list_head = c;
 264         Py_XDECREF(mod);
 265         return PyString_FromString(buf);
 266 }
 267
 268 static PyObject *cpy_flush(cpy_callback_t **list_head, PyObject *args, PyObject *kwds) {
 269         int timeout = -1;
 270         const char *plugin = NULL, *identifier = NULL;
 271         static char *kwlist[] = {"plugin", "timeout", "identifier", NULL};
 272
 273         if (PyArg_ParseTupleAndKeywords(args, kwds, "|ziz", kwlist, &plugin, &timeout, &identifier) == 0) return NULL;
 274         Py_BEGIN_ALLOW_THREADS
 275         plugin_flush(plugin, timeout, identifier);
 276         Py_END_ALLOW_THREADS
 277         Py_RETURN_NONE;
 278 }
 279
 280 static PyObject *cpy_register_config(PyObject *self, PyObject *args, PyObject *kwds) {
 281         return cpy_register_generic(&cpy_config_callbacks, args, kwds, 1);
 282 }
 283
 284 static PyObject *cpy_register_init(PyObject *self, PyObject *args, PyObject *kwds) {
 285         return cpy_register_generic(&cpy_init_callbacks, args, kwds, 0);
 286 }
 287
 288 typedef int reg_function_t(const char *name, void *callback, void *data);
 289
 290 static PyObject *cpy_register_generic_userdata(void *reg, void *handler, PyObject *args, PyObject *kwds, int short_name) {
 291         char buf[512];
 292         reg_function_t *register_function = (reg_function_t *) reg;
 293         cpy_callback_t *c = NULL;
 294         user_data_t *user_data = NULL;
 295         const char *name = NULL;
 296         PyObject *callback = NULL, *data = NULL;
 297         static char *kwlist[] = {"callback", "data", "name", NULL};
 298
 299         if (PyArg_ParseTupleAndKeywords(args, kwds, "O|Oz", kwlist, &callback, &data, &name) == 0) return NULL;
 300         if (PyCallable_Check(callback) == 0) {
 301                 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
 302                 return NULL;
 303         }
 304         cpy_build_name(buf, sizeof(buf), callback, name, short_name);
 305
 306         Py_INCREF(callback);
 307         Py_XINCREF(data);
 308         c = malloc(sizeof(*c));
 309         c->name = strdup(buf);
 310         c->callback = callback;
 311         c->data = data;
 312         c->next = NULL;
 313         user_data = malloc(sizeof(*user_data));
 314         user_data->free_func = cpy_destroy_user_data;
 315         user_data->data = c;
 316         register_function(buf, handler, user_data);
 317         return PyString_FromString(buf);
 318 }
 319
 320 static PyObject *cpy_register_read(PyObject *self, PyObject *args, PyObject *kwds) {
 321         char buf[512];
 322         cpy_callback_t *c = NULL;
 323         user_data_t *user_data = NULL;
 324         double interval = 0;
 325         const char *name = NULL;
 326         PyObject *callback = NULL, *data = NULL;
 327         struct timespec ts;
 328         static char *kwlist[] = {"callback", "interval", "data", "name", NULL};
 329
 330         if (PyArg_ParseTupleAndKeywords(args, kwds, "O|dOz", kwlist, &callback, &interval, &data, &name) == 0) return NULL;
 331         if (PyCallable_Check(callback) == 0) {
 332                 PyErr_SetString(PyExc_TypeError, "callback needs a be a callable object.");
 333                 return NULL;
 334         }
 335         cpy_build_name(buf, sizeof(buf), callback, name, 0);
 336
 337         Py_INCREF(callback);
 338         Py_XINCREF(data);
 339         c = malloc(sizeof(*c));
 340         c->name = strdup(buf);
 341         c->callback = callback;
 342         c->data = data;
 343         c->next = NULL;
 344         user_data = malloc(sizeof(*user_data));
 345         user_data->free_func = cpy_destroy_user_data;
 346         user_data->data = c;
 347         ts.tv_sec = interval;
 348         ts.tv_nsec = (interval - ts.tv_sec) * 1000000000;
 349         plugin_register_complex_read(buf, cpy_read_callback, &ts, user_data);
 350         return PyString_FromString(buf);
 351 }
 352
 353 static PyObject *cpy_register_log(PyObject *self, PyObject *args, PyObject *kwds) {
 354         return cpy_register_generic_userdata(plugin_register_log, cpy_log_callback, args, kwds, 0);
 355 }
 356
 357 static PyObject *cpy_register_write(PyObject *self, PyObject *args, PyObject *kwds) {
 358         return cpy_register_generic_userdata(plugin_register_write, cpy_write_callback, args, kwds, 0);
 359 }
 360
 361 static PyObject *cpy_register_flush(PyObject *self, PyObject *args, PyObject *kwds) {
 362         return cpy_register_generic_userdata(plugin_register_flush, cpy_flush_callback, args, kwds, 1);
 363 }
 364
 365 static PyObject *cpy_register_shutdown(PyObject *self, PyObject *args, PyObject *kwds) {
 366         return cpy_register_generic(&cpy_shutdown_callbacks, args, kwds, 0);
 367 }
 368
 369 static PyObject *cpy_error(PyObject *self, PyObject *args) {
 370         const char *text;
 371         if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
 372         Py_BEGIN_ALLOW_THREADS
 373         plugin_log(LOG_ERR, "%s", text);
 374         Py_END_ALLOW_THREADS
 375         Py_RETURN_NONE;
 376 }
 377
 378 static PyObject *cpy_warning(PyObject *self, PyObject *args) {
 379         const char *text;
 380         if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
 381         Py_BEGIN_ALLOW_THREADS
 382         plugin_log(LOG_WARNING, "%s", text);
 383         Py_END_ALLOW_THREADS
 384         Py_RETURN_NONE;
 385 }
 386
 387 static PyObject *cpy_notice(PyObject *self, PyObject *args) {
 388         const char *text;
 389         if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
 390         Py_BEGIN_ALLOW_THREADS
 391         plugin_log(LOG_NOTICE, "%s", text);
 392         Py_END_ALLOW_THREADS
 393         Py_RETURN_NONE;
 394 }
 395
 396 static PyObject *cpy_info(PyObject *self, PyObject *args) {
 397         const char *text;
 398         if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
 399         Py_BEGIN_ALLOW_THREADS
 400         plugin_log(LOG_INFO, "%s", text);
 401         Py_END_ALLOW_THREADS
 402         Py_RETURN_NONE;
 403 }
 404
 405 static PyObject *cpy_debug(PyObject *self, PyObject *args) {
 406 #ifdef COLLECT_DEBUG
 407         const char *text;
 408         if (PyArg_ParseTuple(args, "s", &text) == 0) return NULL;
 409         plugin_log(LOG_DEBUG, "%s", text);
 410 #endif
 411         Py_RETURN_NONE;
 412 }
 413
 414 static PyObject *cpy_unregister_generic(cpy_callback_t **list_head, PyObject *arg, const char *desc, int short_name) {
 415         char buf[512];
 416         const char *name;
 417         cpy_callback_t *prev = NULL, *tmp;
 418
 419         if (PyString_Check(arg)) {
 420                 name = PyString_AsString(arg);
 421         } else {
 422                 if (!PyCallable_Check(arg)) {
 423                         PyErr_SetString(PyExc_TypeError, "This function needs a string or a callable object as its only parameter.");
 424                         return NULL;
 425                 }
 426                 cpy_build_name(buf, sizeof(buf), arg, NULL, short_name);
 427                 name = buf;
 428         }
 429         for (tmp = *list_head; tmp; prev = tmp, tmp = tmp->next)
 430                 if (strcmp(name, tmp->name) == 0)
 431                         break;
 432
 433         if (tmp == NULL) {
 434                 PyErr_Format(PyExc_RuntimeError, "Unable to unregister %s callback '%s'.", desc, name);
 435                 return NULL;
 436         }
 437         /* Yes, this is actually save. To call this function the calles has to
 438          * hold the GIL. Well, save as long as there is only one GIL anyway ... */
 439         if (prev == NULL)
 440                 *list_head = tmp->next;
 441         else
 442                 prev->next = tmp->next;
 443         cpy_destroy_user_data(tmp);
 444         Py_RETURN_NONE;
 445 }
 446
 447 typedef int cpy_unregister_function_t(const char *name);
 448
 449 static PyObject *cpy_unregister_generic_userdata(cpy_unregister_function_t *unreg, PyObject *arg, const char *desc, int short_name) {
 450         char buf[512];
 451         const char *name;
 452
 453         if (PyString_Check(arg)) {
 454                 name = PyString_AsString(arg);
 455         } else {
 456                 if (!PyCallable_Check(arg)) {
 457                         PyErr_SetString(PyExc_TypeError, "This function needs a string or a callable object as its only parameter.");
 458                         return NULL;
 459                 }
 460                 cpy_build_name(buf, sizeof(buf), arg, NULL, short_name);
 461                 name = buf;
 462         }
 463         if (unreg(name) == 0)
 464                 Py_RETURN_NONE;
 465         PyErr_Format(PyExc_RuntimeError, "Unable to unregister %s callback '%s'.", desc, name);
 466         return NULL;
 467 }
 468
 469 static PyObject *cpy_unregister_log(PyObject *self, PyObject *arg) {
 470         return cpy_unregister_generic_userdata(plugin_unregister_log, arg, "log", 0);
 471 }
 472
 473 static PyObject *cpy_unregister_init(PyObject *self, PyObject *arg) {
 474         return cpy_unregister_generic(&cpy_init_callbacks, arg, "init", 0);
 475 }
 476
 477 static PyObject *cpy_unregister_config(PyObject *self, PyObject *arg) {
 478         return cpy_unregister_generic(&cpy_config_callbacks, arg, "config", 1);
 479 }
 480
 481 static PyObject *cpy_unregister_read(PyObject *self, PyObject *arg) {
 482         return cpy_unregister_generic_userdata(plugin_unregister_read, arg, "read", 0);
 483 }
 484
 485 static PyObject *cpy_unregister_write(PyObject *self, PyObject *arg) {
 486         return cpy_unregister_generic_userdata(plugin_unregister_write, arg, "write", 0);
 487 }
 488
 489 static PyObject *cpy_unregister_flush(PyObject *self, PyObject *arg) {
 490         return cpy_unregister_generic_userdata(plugin_unregister_flush, arg, "flush", 1);
 491 }
 492
 493 static PyObject *cpy_unregister_shutdown(PyObject *self, PyObject *arg) {
 494         return cpy_unregister_generic(&cpy_shutdown_callbacks, arg, "shutdown", 0);
 495 }
 496
 497 static PyMethodDef cpy_methods[] = {
 498         {"debug", cpy_debug, METH_VARARGS, "This is an unhelpful text."},
 499         {"info", cpy_info, METH_VARARGS, "This is an unhelpful text."},
 500         {"notice", cpy_notice, METH_VARARGS, "This is an unhelpful text."},
 501         {"warning", cpy_warning, METH_VARARGS, "This is an unhelpful text."},
 502         {"error", cpy_error, METH_VARARGS, "This is an unhelpful text."},
 503         {"flush", (PyCFunction) cpy_flush, METH_VARARGS | METH_KEYWORDS, "This is an unhelpful text."},
 504         {"register_log", (PyCFunction) cpy_register_log, METH_VARARGS | METH_KEYWORDS, "This is an unhelpful text."},
 505         {"register_init", (PyCFunction) cpy_register_init, METH_VARARGS | METH_KEYWORDS, "This is an unhelpful text."},
 506         {"register_config", (PyCFunction) cpy_register_config, METH_VARARGS | METH_KEYWORDS, "This is an unhelpful text."},
 507         {"register_read", (PyCFunction) cpy_register_read, METH_VARARGS | METH_KEYWORDS, "This is an unhelpful text."},
 508         {"register_write", (PyCFunction) cpy_register_write, METH_VARARGS | METH_KEYWORDS, "This is an unhelpful text."},
 509         {"register_flush", (PyCFunction) cpy_register_flush, METH_VARARGS | METH_KEYWORDS, "This is an unhelpful text."},
 510         {"register_shutdown", (PyCFunction) cpy_register_shutdown, METH_VARARGS | METH_KEYWORDS, "This is an unhelpful text."},
 511         {"unregister_log", cpy_unregister_log, METH_O, "This is an unhelpful text."},
 512         {"unregister_init", cpy_unregister_init, METH_O, "This is an unhelpful text."},
 513         {"unregister_config", cpy_unregister_config, METH_O, "This is an unhelpful text."},
 514         {"unregister_read", cpy_unregister_read, METH_O, "This is an unhelpful text."},
 515         {"unregister_write", cpy_unregister_write, METH_O, "This is an unhelpful text."},
 516         {"unregister_flush", cpy_unregister_flush, METH_O, "This is an unhelpful text."},
 517         {"unregister_shutdown", cpy_unregister_shutdown, METH_O, "This is an unhelpful text."},
 518         {0, 0, 0, 0}
 519 };
 520
 521 static int cpy_shutdown(void) {
 522         cpy_callback_t *c;
 523         PyObject *ret;
 524
 525         /* This can happen if the module was loaded but not configured. */
 526         if (state != NULL)
 527                 PyEval_RestoreThread(state);
 528
 529         for (c = cpy_shutdown_callbacks; c; c = c->next) {
 530                 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
 531                 if (ret == NULL)
 532                         cpy_log_exception("shutdown callback");
 533                 else
 534                         Py_DECREF(ret);
 535         }
 536         Py_Finalize();
 537         return 0;
 538 }
 539
 540 static void *cpy_interactive(void *data) {
 541         CPY_LOCK_THREADS
 542                 if (PyImport_ImportModule("readline") == NULL) {
 543                         /* This interactive session will suck. */
 544                         cpy_log_exception("interactive session init");
 545                 }
 546                 PyRun_InteractiveLoop(stdin, "<stdin>");
 547         CPY_RELEASE_THREADS
 548         NOTICE("python: Interactive interpreter exited, stopping collectd ...");
 549         raise(SIGINT);
 550         return NULL;
 551 }
 552
 553 static int cpy_init(void) {
 554         cpy_callback_t *c;
 555         PyObject *ret;
 556         static pthread_t thread;
 557
 558         PyEval_InitThreads();
 559         /* Now it's finally OK to use python threads. */
 560         for (c = cpy_init_callbacks; c; c = c->next) {
 561                 ret = PyObject_CallFunctionObjArgs(c->callback, c->data, (void *) 0); /* New reference. */
 562                 if (ret == NULL)
 563                         cpy_log_exception("init callback");
 564                 else
 565                         Py_DECREF(ret);
 566         }
 567         state = PyEval_SaveThread();
 568         if (do_interactive) {
 569                 if (pthread_create(&thread, NULL, cpy_interactive, NULL)) {
 570                         ERROR("python: Error creating thread for interactive interpreter.");
 571                 }
 572         }
 573
 574         return 0;
 575 }
 576
 577 static PyObject *cpy_oconfig_to_pyconfig(oconfig_item_t *ci, PyObject *parent) {
 578         int i;
 579         PyObject *item, *values, *children, *tmp;
 580
 581         if (parent == NULL)
 582                 parent = Py_None;
 583
 584         values = PyTuple_New(ci->values_num); /* New reference. */
 585         for (i = 0; i < ci->values_num; ++i) {
 586                 if (ci->values[i].type == OCONFIG_TYPE_STRING) {
 587                         PyTuple_SET_ITEM(values, i, PyString_FromString(ci->values[i].value.string));
 588                 } else if (ci->values[i].type == OCONFIG_TYPE_NUMBER) {
 589                         PyTuple_SET_ITEM(values, i, PyFloat_FromDouble(ci->values[i].value.number));
 590                 } else if (ci->values[i].type == OCONFIG_TYPE_BOOLEAN) {
 591                         PyTuple_SET_ITEM(values, i, PyBool_FromLong(ci->values[i].value.boolean));
 592                 }
 593         }
 594
 595         item = PyObject_CallFunction((PyObject *) &ConfigType, "sONO", ci->key, parent, values, Py_None);
 596         if (item == NULL)
 597                 return NULL;
 598         children = PyTuple_New(ci->children_num); /* New reference. */
 599         for (i = 0; i < ci->children_num; ++i) {
 600                 PyTuple_SET_ITEM(children, i, cpy_oconfig_to_pyconfig(ci->children + i, item));
 601         }
 602         tmp = ((Config *) item)->children;
 603         ((Config *) item)->children = children;
 604         Py_XDECREF(tmp);
 605         return item;
 606 }
 607
 608 static int cpy_config(oconfig_item_t *ci) {
 609         int i;
 610         PyObject *sys, *tb;
 611         PyObject *sys_path;
 612         PyObject *module;
 613
 614         /* Ok in theory we shouldn't do initialization at this point
 615          * but we have to. In order to give python scripts a chance
 616          * to register a config callback we need to be able to execute
 617          * python code during the config callback so we have to start
 618          * the interpreter here. */
 619         /* Do *not* use the python "thread" module at this point! */
 620         Py_Initialize();
 621
 622         PyType_Ready(&ConfigType);
 623         PyType_Ready(&PluginDataType);
 624         ValuesType.tp_base = &PluginDataType;
 625         PyType_Ready(&ValuesType);
 626         sys = PyImport_ImportModule("sys"); /* New reference. */
 627         if (sys == NULL) {
 628                 cpy_log_exception("python initialization");
 629                 return 1;
 630         }
 631         sys_path = PyObject_GetAttrString(sys, "path"); /* New reference. */
 632         Py_DECREF(sys);
 633         if (sys_path == NULL) {
 634                 cpy_log_exception("python initialization");
 635                 return 1;
 636         }
 637         module = Py_InitModule("collectd", cpy_methods); /* Borrowed reference. */
 638         PyModule_AddObject(module, "Config", (PyObject *) &ConfigType); /* Steals a reference. */
 639         PyModule_AddObject(module, "Values", (PyObject *) &ValuesType); /* Steals a reference. */
 640         PyModule_AddIntConstant(module, "LOG_DEBUG", LOG_DEBUG);
 641         PyModule_AddIntConstant(module, "LOG_INFO", LOG_INFO);
 642         PyModule_AddIntConstant(module, "LOG_NOTICE", LOG_NOTICE);
 643         PyModule_AddIntConstant(module, "LOG_WARNING", LOG_WARNING);
 644         PyModule_AddIntConstant(module, "LOG_ERROR", LOG_ERR);
 645         for (i = 0; i < ci->children_num; ++i) {
 646                 oconfig_item_t *item = ci->children + i;
 647
 648                 if (strcasecmp(item->key, "Interactive") == 0) {
 649                         if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_BOOLEAN)
 650                                 continue;
 651                         do_interactive = item->values[0].value.boolean;
 652                 } else if (strcasecmp(item->key, "LogTraces") == 0) {
 653                         if (item->values_num != 1 || item->values[0].type != OCONFIG_TYPE_BOOLEAN)
 654                                 continue;
 655                         if (!item->values[0].value.boolean) {
 656                                 Py_XDECREF(cpy_format_exception);
 657                                 cpy_format_exception = NULL;
 658                                 continue;
 659                         }
 660                         if (cpy_format_exception)
 661                                 continue;
 662                         tb = PyImport_ImportModule("traceback"); /* New reference. */
 663                         if (tb == NULL) {
 664                                 cpy_log_exception("python initialization");
 665                                 continue;
 666                         }
 667                         cpy_format_exception = PyObject_GetAttrString(tb, "format_exception"); /* New reference. */
 668                         Py_DECREF(tb);
 669                         if (cpy_format_exception == NULL)
 670                                 cpy_log_exception("python initialization");
 671                 } else if (strcasecmp(item->key, "ModulePath") == 0) {
 672                         char *dir = NULL;
 673                         PyObject *dir_object;
 674
 675                         if (cf_util_get_string(item, &dir) != 0)
 676                                 continue;
 677                         dir_object = PyString_FromString(dir); /* New reference. */
 678                         if (dir_object == NULL) {
 679                                 ERROR("python plugin: Unable to convert \"%s\" to "
 680                                       "a python object.", dir);
 681                                 free(dir);
 682                                 cpy_log_exception("python initialization");
 683                                 continue;
 684                         }
 685                         if (PyList_Append(sys_path, dir_object) != 0) {
 686                                 ERROR("python plugin: Unable to append \"%s\" to "
 687                                       "python module path.", dir);
 688                                 cpy_log_exception("python initialization");
 689                         }
 690                         Py_DECREF(dir_object);
 691                         free(dir);
 692                 } else if (strcasecmp(item->key, "Import") == 0) {
 693                         char *module_name = NULL;
 694                         PyObject *module;
 695
 696                         if (cf_util_get_string(item, &module_name) != 0)
 697                                 continue;
 698                         module = PyImport_ImportModule(module_name); /* New reference. */
 699                         if (module == NULL) {
 700                                 ERROR("python plugin: Error importing module \"%s\".", module_name);
 701                                 cpy_log_exception("python initialization");
 702                                 PyErr_Print();
 703                         }
 704                         free(module_name);
 705                         Py_XDECREF(module);
 706                 } else if (strcasecmp(item->key, "Module") == 0) {
 707                         char *name = NULL;
 708                         cpy_callback_t *c;
 709                         PyObject *ret;
 710
 711                         if (cf_util_get_string(item, &name) != 0)
 712                                 continue;
 713                         for (c = cpy_config_callbacks; c; c = c->next) {
 714                                 if (strcasecmp(c->name + 7, name) == 0)
 715                                         break;
 716                         }
 717                         if (c == NULL) {
 718                                 WARNING("python plugin: Found a configuration for the \"%s\" plugin, "
 719                                         "but the plugin isn't loaded or didn't register "
 720                                         "a configuration callback.", name);
 721                                 free(name);
 722                                 continue;
 723                         }
 724                         free(name);
 725                         if (c->data == NULL)
 726                                 ret = PyObject_CallFunction(c->callback, "N",
 727                                         cpy_oconfig_to_pyconfig(item, NULL)); /* New reference. */
 728                         else
 729                                 ret = PyObject_CallFunction(c->callback, "NO",
 730                                         cpy_oconfig_to_pyconfig(item, NULL), c->data); /* New reference. */
 731                         if (ret == NULL)
 732                                 cpy_log_exception("loading module");
 733                         else
 734                                 Py_DECREF(ret);
 735                 } else {
 736                         WARNING("python plugin: Ignoring unknown config key \"%s\".", item->key);
 737                 }
 738         }
 739         Py_DECREF(sys_path);
 740         return 0;
 741 }
 742
 743 void module_register(void) {
 744         plugin_register_complex_config("python", cpy_config);
 745         plugin_register_init("python", cpy_init);
 746 //      plugin_register_read("python", cna_read);
 747         plugin_register_shutdown("python", cpy_shutdown);
 748 }