2 * collectd - src/filter_chain.c
3 * Copyright (C) 2008-2010 Florian octo Forster
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:
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions of the Software.
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.
24 * Florian octo Forster <octo at collectd.org>
29 #include "configfile.h"
31 #include "utils_complain.h"
33 #include "filter_chain.h"
38 /* List of matches, used in fc_rule_t and for the global `match_list_head'
41 typedef struct fc_match_s fc_match_t; /* {{{ */
44 char name[DATA_MAX_NAME_LEN];
50 /* List of targets, used in fc_rule_t and for the global `target_list_head'
53 typedef struct fc_target_s fc_target_t; /* {{{ */
56 char name[DATA_MAX_NAME_LEN];
62 /* List of rules, used in fc_chain_t */
64 typedef struct fc_rule_s fc_rule_t; /* {{{ */
67 char name[DATA_MAX_NAME_LEN];
73 /* List of chains, used for `chain_list_head' */
74 struct fc_chain_s /* {{{ */
76 char name[DATA_MAX_NAME_LEN];
82 /* Writer configuration. */
84 typedef struct fc_writer_s fc_writer_t; /* {{{ */
88 c_complain_t complaint;
94 static fc_match_t *match_list_head;
95 static fc_target_t *target_list_head;
96 static fc_chain_t *chain_list_head;
101 static void fc_free_matches (fc_match_t *m) /* {{{ */
106 if (m->proc.destroy != NULL)
107 (*m->proc.destroy) (&m->user_data);
108 else if (m->user_data != NULL)
110 ERROR ("Filter subsystem: fc_free_matches: There is user data, but no "
111 "destroy functions has been specified. "
112 "Memory will probably be lost!");
116 fc_free_matches (m->next);
119 } /* }}} void fc_free_matches */
121 static void fc_free_targets (fc_target_t *t) /* {{{ */
126 if (t->proc.destroy != NULL)
127 (*t->proc.destroy) (&t->user_data);
128 else if (t->user_data != NULL)
130 ERROR ("Filter subsystem: fc_free_targets: There is user data, but no "
131 "destroy functions has been specified. "
132 "Memory will probably be lost!");
136 fc_free_targets (t->next);
139 } /* }}} void fc_free_targets */
141 static void fc_free_rules (fc_rule_t *r) /* {{{ */
146 fc_free_matches (r->matches);
147 fc_free_targets (r->targets);
150 fc_free_rules (r->next);
153 } /* }}} void fc_free_rules */
155 static void fc_free_chains (fc_chain_t *c) /* {{{ */
160 fc_free_rules (c->rules);
161 fc_free_targets (c->targets);
164 fc_free_chains (c->next);
167 } /* }}} void fc_free_chains */
169 static char *fc_strdup (const char *orig) /* {{{ */
177 sz = strlen (orig) + 1;
182 memcpy (dest, orig, sz);
185 } /* }}} char *fc_strdup */
190 * The configuration looks somewhat like this:
196 * Type "^mysql_command$"
197 * TypeInstance "^show_"
208 static int fc_config_add_match (fc_match_t **matches_head, /* {{{ */
215 if ((ci->values_num != 1)
216 || (ci->values[0].type != OCONFIG_TYPE_STRING))
218 WARNING ("Filter subsystem: `Match' blocks require "
219 "exactly one string argument.");
223 ptr = match_list_head;
226 if (strcasecmp (ptr->name, ci->values[0].value.string) == 0)
233 WARNING ("Filter subsystem: Cannot find a \"%s\" match. "
234 "Did you load the appropriate plugin?",
235 ci->values[0].value.string);
239 m = calloc (1, sizeof (*m));
242 ERROR ("fc_config_add_match: calloc failed.");
246 sstrncpy (m->name, ptr->name, sizeof (m->name));
247 memcpy (&m->proc, &ptr->proc, sizeof (m->proc));
251 if (m->proc.create != NULL)
253 status = (*m->proc.create) (ci, &m->user_data);
256 WARNING ("Filter subsystem: Failed to create a %s match.",
263 if (*matches_head != NULL)
266 while (ptr->next != NULL)
277 } /* }}} int fc_config_add_match */
279 static int fc_config_add_target (fc_target_t **targets_head, /* {{{ */
286 if ((ci->values_num != 1)
287 || (ci->values[0].type != OCONFIG_TYPE_STRING))
289 WARNING ("Filter subsystem: `Target' blocks require "
290 "exactly one string argument.");
294 ptr = target_list_head;
297 if (strcasecmp (ptr->name, ci->values[0].value.string) == 0)
304 WARNING ("Filter subsystem: Cannot find a \"%s\" target. "
305 "Did you load the appropriate plugin?",
306 ci->values[0].value.string);
310 t = calloc (1, sizeof (*t));
313 ERROR ("fc_config_add_target: calloc failed.");
317 sstrncpy (t->name, ptr->name, sizeof (t->name));
318 memcpy (&t->proc, &ptr->proc, sizeof (t->proc));
322 if (t->proc.create != NULL)
324 status = (*t->proc.create) (ci, &t->user_data);
327 WARNING ("Filter subsystem: Failed to create a %s target.",
338 if (*targets_head != NULL)
341 while (ptr->next != NULL)
352 } /* }}} int fc_config_add_target */
354 static int fc_config_add_rule (fc_chain_t *chain, /* {{{ */
358 char rule_name[2*DATA_MAX_NAME_LEN] = "Unnamed rule";
361 if (ci->values_num > 1)
363 WARNING ("Filter subsystem: `Rule' blocks have at most one argument.");
366 else if ((ci->values_num == 1)
367 && (ci->values[0].type != OCONFIG_TYPE_STRING))
369 WARNING ("Filter subsystem: `Rule' blocks expect one string argument "
370 "or no argument at all.");
374 rule = calloc (1, sizeof (*rule));
377 ERROR ("fc_config_add_rule: calloc failed.");
381 if (ci->values_num == 1)
383 sstrncpy (rule->name, ci->values[0].value.string, sizeof (rule->name));
384 ssnprintf (rule_name, sizeof (rule_name), "Rule \"%s\"",
385 ci->values[0].value.string);
388 for (int i = 0; i < ci->children_num; i++)
390 oconfig_item_t *option = ci->children + i;
392 if (strcasecmp ("Match", option->key) == 0)
393 status = fc_config_add_match (&rule->matches, option);
394 else if (strcasecmp ("Target", option->key) == 0)
395 status = fc_config_add_target (&rule->targets, option);
398 WARNING ("Filter subsystem: %s: Option `%s' not allowed "
399 "inside a <Rule> block.", rule_name, option->key);
405 } /* for (ci->children) */
407 /* Additional sanity checking. */
410 if (rule->targets == NULL)
412 WARNING ("Filter subsystem: %s: No target has been specified.",
419 } /* while (status == 0) */
423 fc_free_rules (rule);
427 if (chain->rules != NULL)
432 while (ptr->next != NULL)
443 } /* }}} int fc_config_add_rule */
445 static int fc_config_add_chain (const oconfig_item_t *ci) /* {{{ */
447 fc_chain_t *chain = NULL;
451 if ((ci->values_num != 1)
452 || (ci->values[0].type != OCONFIG_TYPE_STRING))
454 WARNING ("Filter subsystem: <Chain> blocks require exactly one "
459 if (chain_list_head != NULL)
461 if ((chain = fc_chain_get_by_name (ci->values[0].value.string)) != NULL)
467 chain = calloc (1, sizeof (*chain));
470 ERROR ("fc_config_add_chain: calloc failed.");
473 sstrncpy (chain->name, ci->values[0].value.string, sizeof (chain->name));
476 for (int i = 0; i < ci->children_num; i++)
478 oconfig_item_t *option = ci->children + i;
480 if (strcasecmp ("Rule", option->key) == 0)
481 status = fc_config_add_rule (chain, option);
482 else if (strcasecmp ("Target", option->key) == 0)
483 status = fc_config_add_target (&chain->targets, option);
486 WARNING ("Filter subsystem: Chain %s: Option `%s' not allowed "
487 "inside a <Chain> block.", chain->name, option->key);
493 } /* for (ci->children) */
497 fc_free_chains (chain);
501 if (chain_list_head != NULL)
508 ptr = chain_list_head;
509 while (ptr->next != NULL)
516 chain_list_head = chain;
520 } /* }}} int fc_config_add_chain */
523 * Built-in target "jump"
525 * Prefix `bit' like `_b_uilt-_i_n _t_arget'
527 static int fc_bit_jump_create (const oconfig_item_t *ci, /* {{{ */
530 oconfig_item_t *ci_chain;
532 if (ci->children_num != 1)
534 ERROR ("Filter subsystem: The built-in target `jump' needs exactly "
535 "one `Chain' argument!");
539 ci_chain = ci->children;
540 if (strcasecmp ("Chain", ci_chain->key) != 0)
542 ERROR ("Filter subsystem: The built-in target `jump' does not "
543 "support the configuration option `%s'.",
548 if ((ci_chain->values_num != 1)
549 || (ci_chain->values[0].type != OCONFIG_TYPE_STRING))
551 ERROR ("Filter subsystem: Built-in target `jump': The `Chain' option "
552 "needs exactly one string argument.");
556 *user_data = fc_strdup (ci_chain->values[0].value.string);
557 if (*user_data == NULL)
559 ERROR ("fc_bit_jump_create: fc_strdup failed.");
564 } /* }}} int fc_bit_jump_create */
566 static int fc_bit_jump_destroy (void **user_data) /* {{{ */
568 if (user_data != NULL)
575 } /* }}} int fc_bit_jump_destroy */
577 static int fc_bit_jump_invoke (const data_set_t *ds, /* {{{ */
578 value_list_t *vl, notification_meta_t __attribute__((unused)) **meta,
585 chain_name = *user_data;
587 for (chain = chain_list_head; chain != NULL; chain = chain->next)
588 if (strcasecmp (chain_name, chain->name) == 0)
593 ERROR ("Filter subsystem: Built-in target `jump': There is no chain "
594 "named `%s'.", chain_name);
598 status = fc_process_chain (ds, vl, chain);
601 else if (status == FC_TARGET_STOP)
602 return (FC_TARGET_STOP);
604 return (FC_TARGET_CONTINUE);
605 } /* }}} int fc_bit_jump_invoke */
607 static int fc_bit_stop_invoke (const data_set_t __attribute__((unused)) *ds, /* {{{ */
608 value_list_t __attribute__((unused)) *vl,
609 notification_meta_t __attribute__((unused)) **meta,
610 void __attribute__((unused)) **user_data)
612 return (FC_TARGET_STOP);
613 } /* }}} int fc_bit_stop_invoke */
615 static int fc_bit_return_invoke (const data_set_t __attribute__((unused)) *ds, /* {{{ */
616 value_list_t __attribute__((unused)) *vl,
617 notification_meta_t __attribute__((unused)) **meta,
618 void __attribute__((unused)) **user_data)
620 return (FC_TARGET_RETURN);
621 } /* }}} int fc_bit_return_invoke */
623 static int fc_bit_write_create (const oconfig_item_t *ci, /* {{{ */
626 fc_writer_t *plugin_list = NULL;
627 size_t plugin_list_len = 0;
629 for (int i = 0; i < ci->children_num; i++)
631 oconfig_item_t *child = ci->children + i;
634 if (strcasecmp ("Plugin", child->key) != 0)
636 ERROR ("Filter subsystem: The built-in target `write' does not "
637 "support the configuration option `%s'.",
642 for (int j = 0; j < child->values_num; j++)
646 if (child->values[j].type != OCONFIG_TYPE_STRING)
648 ERROR ("Filter subsystem: Built-in target `write': "
649 "The `Plugin' option accepts only string arguments.");
652 plugin = child->values[j].value.string;
654 temp = realloc (plugin_list, (plugin_list_len + 2)
655 * (sizeof (*plugin_list)));
658 ERROR ("fc_bit_write_create: realloc failed.");
663 plugin_list[plugin_list_len].plugin = fc_strdup (plugin);
664 if (plugin_list[plugin_list_len].plugin == NULL)
666 ERROR ("fc_bit_write_create: fc_strdup failed.");
669 C_COMPLAIN_INIT (&plugin_list[plugin_list_len].complaint);
671 plugin_list[plugin_list_len].plugin = NULL;
672 } /* for (j = 0; j < child->values_num; j++) */
673 } /* for (i = 0; i < ci->children_num; i++) */
675 *user_data = plugin_list;
678 } /* }}} int fc_bit_write_create */
680 static int fc_bit_write_destroy (void **user_data) /* {{{ */
682 fc_writer_t *plugin_list;
684 if ((user_data == NULL) || (*user_data == NULL))
687 plugin_list = *user_data;
689 for (size_t i = 0; plugin_list[i].plugin != NULL; i++)
690 free (plugin_list[i].plugin);
694 } /* }}} int fc_bit_write_destroy */
696 static int fc_bit_write_invoke (const data_set_t *ds, /* {{{ */
697 value_list_t *vl, notification_meta_t __attribute__((unused)) **meta,
700 fc_writer_t *plugin_list;
704 if (user_data != NULL)
705 plugin_list = *user_data;
707 if ((plugin_list == NULL) || (plugin_list[0].plugin == NULL))
709 static c_complain_t write_complaint = C_COMPLAIN_INIT_STATIC;
711 status = plugin_write (/* plugin = */ NULL, ds, vl);
712 if (status == ENOENT)
714 /* in most cases this is a permanent error, so use the complain
715 * mechanism rather than spamming the logs */
716 c_complain (LOG_INFO, &write_complaint,
717 "Filter subsystem: Built-in target `write': Dispatching value to "
718 "all write plugins failed with status %i (ENOENT). "
719 "Most likely this means you didn't load any write plugins.",
722 plugin_log_available_writers ();
724 else if (status != 0)
726 /* often, this is a permanent error (e.g. target system unavailable),
727 * so use the complain mechanism rather than spamming the logs */
728 c_complain (LOG_INFO, &write_complaint,
729 "Filter subsystem: Built-in target `write': Dispatching value to "
730 "all write plugins failed with status %i.", status);
734 assert (status == 0);
735 c_release (LOG_INFO, &write_complaint, "Filter subsystem: "
736 "Built-in target `write': Some write plugin is back to normal "
737 "operation. `write' succeeded.");
742 for (size_t i = 0; plugin_list[i].plugin != NULL; i++)
744 status = plugin_write (plugin_list[i].plugin, ds, vl);
747 c_complain (LOG_INFO, &plugin_list[i].complaint,
748 "Filter subsystem: Built-in target `write': Dispatching value to "
749 "the `%s' plugin failed with status %i.",
750 plugin_list[i].plugin, status);
752 plugin_log_available_writers ();
756 c_release (LOG_INFO, &plugin_list[i].complaint,
757 "Filter subsystem: Built-in target `write': Plugin `%s' is back "
758 "to normal operation. `write' succeeded.", plugin_list[i].plugin);
760 } /* for (i = 0; plugin_list[i] != NULL; i++) */
763 return (FC_TARGET_CONTINUE);
764 } /* }}} int fc_bit_write_invoke */
766 static int fc_init_once (void) /* {{{ */
769 target_proc_t tproc = { 0 };
774 tproc.create = fc_bit_jump_create;
775 tproc.destroy = fc_bit_jump_destroy;
776 tproc.invoke = fc_bit_jump_invoke;
777 fc_register_target ("jump", tproc);
779 memset (&tproc, 0, sizeof (tproc));
781 tproc.destroy = NULL;
782 tproc.invoke = fc_bit_stop_invoke;
783 fc_register_target ("stop", tproc);
785 memset (&tproc, 0, sizeof (tproc));
787 tproc.destroy = NULL;
788 tproc.invoke = fc_bit_return_invoke;
789 fc_register_target ("return", tproc);
791 memset (&tproc, 0, sizeof (tproc));
792 tproc.create = fc_bit_write_create;
793 tproc.destroy = fc_bit_write_destroy;
794 tproc.invoke = fc_bit_write_invoke;
795 fc_register_target ("write", tproc);
799 } /* }}} int fc_init_once */
804 /* Add a match to list of available matches. */
805 int fc_register_match (const char *name, match_proc_t proc) /* {{{ */
809 DEBUG ("fc_register_match (%s);", name);
811 m = calloc (1, sizeof (*m));
815 sstrncpy (m->name, name, sizeof (m->name));
816 memcpy (&m->proc, &proc, sizeof (m->proc));
818 if (match_list_head == NULL)
826 ptr = match_list_head;
827 while (ptr->next != NULL)
834 } /* }}} int fc_register_match */
836 /* Add a target to list of available targets. */
837 int fc_register_target (const char *name, target_proc_t proc) /* {{{ */
841 DEBUG ("fc_register_target (%s);", name);
843 t = calloc (1, sizeof (*t));
847 sstrncpy (t->name, name, sizeof (t->name));
848 memcpy (&t->proc, &proc, sizeof (t->proc));
850 if (target_list_head == NULL)
852 target_list_head = t;
858 ptr = target_list_head;
859 while (ptr->next != NULL)
866 } /* }}} int fc_register_target */
868 fc_chain_t *fc_chain_get_by_name (const char *chain_name) /* {{{ */
870 if (chain_name == NULL)
873 for (fc_chain_t *chain = chain_list_head; chain != NULL; chain = chain->next)
874 if (strcasecmp (chain_name, chain->name) == 0)
878 } /* }}} int fc_chain_get_by_name */
880 int fc_process_chain (const data_set_t *ds, value_list_t *vl, /* {{{ */
884 int status = FC_TARGET_CONTINUE;
889 DEBUG ("fc_process_chain (chain = %s);", chain->name);
891 for (fc_rule_t *rule = chain->rules; rule != NULL; rule = rule->next)
894 status = FC_TARGET_CONTINUE;
896 if (rule->name[0] != 0)
898 DEBUG ("fc_process_chain (%s): Testing the `%s' rule.",
899 chain->name, rule->name);
902 /* N. B.: rule->matches may be NULL. */
903 for (match = rule->matches; match != NULL; match = match->next)
905 /* FIXME: Pass the meta-data to match targets here (when implemented). */
906 status = (*match->proc.match) (ds, vl, /* meta = */ NULL,
910 WARNING ("fc_process_chain (%s): A match failed.", chain->name);
913 else if (status != FC_MATCH_MATCHES)
917 /* for-loop has been aborted: Either error or no match. */
920 status = FC_TARGET_CONTINUE;
924 if (rule->name[0] != 0)
926 DEBUG ("fc_process_chain (%s): Rule `%s' matches.",
927 chain->name, rule->name);
930 for (target = rule->targets; target != NULL; target = target->next)
932 /* If we get here, all matches have matched the value. Execute the
934 /* FIXME: Pass the meta-data to match targets here (when implemented). */
935 status = (*target->proc.invoke) (ds, vl, /* meta = */ NULL,
939 WARNING ("fc_process_chain (%s): A target failed.", chain->name);
942 else if (status == FC_TARGET_CONTINUE)
944 else if (status == FC_TARGET_STOP)
946 else if (status == FC_TARGET_RETURN)
950 WARNING ("fc_process_chain (%s): Unknown return value "
951 "from target `%s': %i",
952 chain->name, target->name, status);
956 if ((status == FC_TARGET_STOP) || (status == FC_TARGET_RETURN))
958 if (rule->name[0] != 0)
960 DEBUG ("fc_process_chain (%s): Rule `%s' signaled "
962 chain->name, rule->name,
963 (status == FC_TARGET_STOP) ? "stop" : "return");
969 if ((status == FC_TARGET_STOP) || (status == FC_TARGET_RETURN))
972 DEBUG ("fc_process_chain (%s): Executing the default targets.",
975 status = FC_TARGET_CONTINUE;
976 for (target = chain->targets; target != NULL; target = target->next)
978 /* If we get here, all matches have matched the value. Execute the
980 /* FIXME: Pass the meta-data to match targets here (when implemented). */
981 status = (*target->proc.invoke) (ds, vl, /* meta = */ NULL,
985 WARNING ("fc_process_chain (%s): The default target failed.",
988 else if (status == FC_TARGET_CONTINUE)
990 else if (status == FC_TARGET_STOP)
992 else if (status == FC_TARGET_RETURN)
996 WARNING ("fc_process_chain (%s): Unknown return value "
997 "from target `%s': %i",
998 chain->name, target->name, status);
1002 if ((status == FC_TARGET_STOP)
1003 || (status == FC_TARGET_RETURN))
1005 assert (target != NULL);
1006 DEBUG ("fc_process_chain (%s): Default target `%s' signaled "
1007 "the %s condition.",
1008 chain->name, target->name,
1009 (status == FC_TARGET_STOP) ? "stop" : "return");
1010 if (status == FC_TARGET_STOP)
1011 return (FC_TARGET_STOP);
1013 return (FC_TARGET_CONTINUE);
1016 DEBUG ("fc_process_chain (%s): Signaling `continue' at end of chain.",
1019 return (FC_TARGET_CONTINUE);
1020 } /* }}} int fc_process_chain */
1022 /* Iterate over all rules in the chain and execute all targets for which all
1024 int fc_default_action (const data_set_t *ds, value_list_t *vl) /* {{{ */
1026 /* FIXME: Pass the meta-data to match targets here (when implemented). */
1027 return (fc_bit_write_invoke (ds, vl,
1028 /* meta = */ NULL, /* user_data = */ NULL));
1029 } /* }}} int fc_default_action */
1031 int fc_configure (const oconfig_item_t *ci) /* {{{ */
1038 if (strcasecmp ("Chain", ci->key) == 0)
1039 return (fc_config_add_chain (ci));
1041 WARNING ("Filter subsystem: Unknown top level config option `%s'.",
1045 } /* }}} int fc_configure */
1047 /* vim: set sw=2 sts=2 et fdm=marker : */