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>
28 #include "configfile.h"
30 #include "utils_complain.h"
32 #include "filter_chain.h"
37 /* List of matches, used in fc_rule_t and for the global `match_list_head'
40 typedef struct fc_match_s fc_match_t; /* {{{ */
43 char name[DATA_MAX_NAME_LEN];
49 /* List of targets, used in fc_rule_t and for the global `target_list_head'
52 typedef struct fc_target_s fc_target_t; /* {{{ */
55 char name[DATA_MAX_NAME_LEN];
61 /* List of rules, used in fc_chain_t */
63 typedef struct fc_rule_s fc_rule_t; /* {{{ */
66 char name[DATA_MAX_NAME_LEN];
72 /* List of chains, used for `chain_list_head' */
73 struct fc_chain_s /* {{{ */
75 char name[DATA_MAX_NAME_LEN];
81 /* Writer configuration. */
83 typedef struct fc_writer_s fc_writer_t; /* {{{ */
87 c_complain_t complaint;
93 static fc_match_t *match_list_head;
94 static fc_target_t *target_list_head;
95 static fc_chain_t *chain_list_head;
100 static void fc_free_matches (fc_match_t *m) /* {{{ */
105 if (m->proc.destroy != NULL)
106 (*m->proc.destroy) (&m->user_data);
107 else if (m->user_data != NULL)
109 ERROR ("Filter subsystem: fc_free_matches: There is user data, but no "
110 "destroy functions has been specified. "
111 "Memory will probably be lost!");
115 fc_free_matches (m->next);
118 } /* }}} void fc_free_matches */
120 static void fc_free_targets (fc_target_t *t) /* {{{ */
125 if (t->proc.destroy != NULL)
126 (*t->proc.destroy) (&t->user_data);
127 else if (t->user_data != NULL)
129 ERROR ("Filter subsystem: fc_free_targets: There is user data, but no "
130 "destroy functions has been specified. "
131 "Memory will probably be lost!");
135 fc_free_targets (t->next);
138 } /* }}} void fc_free_targets */
140 static void fc_free_rules (fc_rule_t *r) /* {{{ */
145 fc_free_matches (r->matches);
146 fc_free_targets (r->targets);
149 fc_free_rules (r->next);
152 } /* }}} void fc_free_rules */
154 static void fc_free_chains (fc_chain_t *c) /* {{{ */
159 fc_free_rules (c->rules);
160 fc_free_targets (c->targets);
163 fc_free_chains (c->next);
166 } /* }}} void fc_free_chains */
168 static char *fc_strdup (const char *orig) /* {{{ */
176 sz = strlen (orig) + 1;
177 dest = (char *) malloc (sz);
181 memcpy (dest, orig, sz);
184 } /* }}} char *fc_strdup */
189 * The configuration looks somewhat like this:
195 * Type "^mysql_command$"
196 * TypeInstance "^show_"
207 static int fc_config_add_match (fc_match_t **matches_head, /* {{{ */
214 if ((ci->values_num != 1)
215 || (ci->values[0].type != OCONFIG_TYPE_STRING))
217 WARNING ("Filter subsystem: `Match' blocks require "
218 "exactly one string argument.");
222 ptr = match_list_head;
225 if (strcasecmp (ptr->name, ci->values[0].value.string) == 0)
232 WARNING ("Filter subsystem: Cannot find a \"%s\" match. "
233 "Did you load the appropriate plugin?",
234 ci->values[0].value.string);
238 m = (fc_match_t *) malloc (sizeof (*m));
241 ERROR ("fc_config_add_match: malloc failed.");
244 memset (m, 0, sizeof (*m));
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 = (fc_target_t *) malloc (sizeof (*t));
313 ERROR ("fc_config_add_target: malloc failed.");
316 memset (t, 0, sizeof (*t));
318 sstrncpy (t->name, ptr->name, sizeof (t->name));
319 memcpy (&t->proc, &ptr->proc, sizeof (t->proc));
323 if (t->proc.create != NULL)
325 status = (*t->proc.create) (ci, &t->user_data);
328 WARNING ("Filter subsystem: Failed to create a %s target.",
339 if (*targets_head != NULL)
342 while (ptr->next != NULL)
353 } /* }}} int fc_config_add_target */
355 static int fc_config_add_rule (fc_chain_t *chain, /* {{{ */
359 char rule_name[2*DATA_MAX_NAME_LEN] = "Unnamed rule";
363 if (ci->values_num > 1)
365 WARNING ("Filter subsystem: `Rule' blocks have at most one argument.");
368 else if ((ci->values_num == 1)
369 && (ci->values[0].type != OCONFIG_TYPE_STRING))
371 WARNING ("Filter subsystem: `Rule' blocks expect one string argument "
372 "or no argument at all.");
376 rule = (fc_rule_t *) malloc (sizeof (*rule));
379 ERROR ("fc_config_add_rule: malloc failed.");
382 memset (rule, 0, sizeof (*rule));
385 if (ci->values_num == 1)
387 sstrncpy (rule->name, ci->values[0].value.string, sizeof (rule->name));
388 ssnprintf (rule_name, sizeof (rule_name), "Rule \"%s\"",
389 ci->values[0].value.string);
392 for (i = 0; i < ci->children_num; i++)
394 oconfig_item_t *option = ci->children + i;
397 if (strcasecmp ("Match", option->key) == 0)
398 status = fc_config_add_match (&rule->matches, option);
399 else if (strcasecmp ("Target", option->key) == 0)
400 status = fc_config_add_target (&rule->targets, option);
403 WARNING ("Filter subsystem: %s: Option `%s' not allowed "
404 "inside a <Rule> block.", rule_name, option->key);
410 } /* for (ci->children) */
412 /* Additional sanity checking. */
415 if (rule->targets == NULL)
417 WARNING ("Filter subsystem: %s: No target has been specified.",
424 } /* while (status == 0) */
428 fc_free_rules (rule);
432 if (chain->rules != NULL)
437 while (ptr->next != NULL)
448 } /* }}} int fc_config_add_rule */
450 static int fc_config_add_chain (const oconfig_item_t *ci) /* {{{ */
452 fc_chain_t *chain = NULL;
457 if ((ci->values_num != 1)
458 || (ci->values[0].type != OCONFIG_TYPE_STRING))
460 WARNING ("Filter subsystem: <Chain> blocks require exactly one "
465 if (chain_list_head != NULL)
467 if ((chain = fc_chain_get_by_name (ci->values[0].value.string)) != NULL)
473 chain = (fc_chain_t *) malloc (sizeof (*chain));
476 ERROR ("fc_config_add_chain: malloc failed.");
479 memset (chain, 0, sizeof (*chain));
480 sstrncpy (chain->name, ci->values[0].value.string, sizeof (chain->name));
482 chain->targets = NULL;
486 for (i = 0; i < ci->children_num; i++)
488 oconfig_item_t *option = ci->children + i;
491 if (strcasecmp ("Rule", option->key) == 0)
492 status = fc_config_add_rule (chain, option);
493 else if (strcasecmp ("Target", option->key) == 0)
494 status = fc_config_add_target (&chain->targets, option);
497 WARNING ("Filter subsystem: Chain %s: Option `%s' not allowed "
498 "inside a <Chain> block.", chain->name, option->key);
504 } /* for (ci->children) */
508 fc_free_chains (chain);
512 if (chain_list_head != NULL)
519 ptr = chain_list_head;
520 while (ptr->next != NULL)
527 chain_list_head = chain;
531 } /* }}} int fc_config_add_chain */
534 * Built-in target "jump"
536 * Prefix `bit' like `_b_uilt-_i_n _t_arget'
538 static int fc_bit_jump_create (const oconfig_item_t *ci, /* {{{ */
541 oconfig_item_t *ci_chain;
543 if (ci->children_num != 1)
545 ERROR ("Filter subsystem: The built-in target `jump' needs exactly "
546 "one `Chain' argument!");
550 ci_chain = ci->children;
551 if (strcasecmp ("Chain", ci_chain->key) != 0)
553 ERROR ("Filter subsystem: The built-in target `jump' does not "
554 "support the configuration option `%s'.",
559 if ((ci_chain->values_num != 1)
560 || (ci_chain->values[0].type != OCONFIG_TYPE_STRING))
562 ERROR ("Filter subsystem: Built-in target `jump': The `Chain' option "
563 "needs exactly one string argument.");
567 *user_data = fc_strdup (ci_chain->values[0].value.string);
568 if (*user_data == NULL)
570 ERROR ("fc_bit_jump_create: fc_strdup failed.");
575 } /* }}} int fc_bit_jump_create */
577 static int fc_bit_jump_destroy (void **user_data) /* {{{ */
579 if (user_data != NULL)
586 } /* }}} int fc_bit_jump_destroy */
588 static int fc_bit_jump_invoke (const data_set_t *ds, /* {{{ */
589 value_list_t *vl, notification_meta_t __attribute__((unused)) **meta,
596 chain_name = *user_data;
598 for (chain = chain_list_head; chain != NULL; chain = chain->next)
599 if (strcasecmp (chain_name, chain->name) == 0)
604 ERROR ("Filter subsystem: Built-in target `jump': There is no chain "
605 "named `%s'.", chain_name);
609 status = fc_process_chain (ds, vl, chain);
612 else if (status == FC_TARGET_STOP)
613 return (FC_TARGET_STOP);
615 return (FC_TARGET_CONTINUE);
616 } /* }}} int fc_bit_jump_invoke */
618 static int fc_bit_stop_invoke (const data_set_t __attribute__((unused)) *ds, /* {{{ */
619 value_list_t __attribute__((unused)) *vl,
620 notification_meta_t __attribute__((unused)) **meta,
621 void __attribute__((unused)) **user_data)
623 return (FC_TARGET_STOP);
624 } /* }}} int fc_bit_stop_invoke */
626 static int fc_bit_return_invoke (const data_set_t __attribute__((unused)) *ds, /* {{{ */
627 value_list_t __attribute__((unused)) *vl,
628 notification_meta_t __attribute__((unused)) **meta,
629 void __attribute__((unused)) **user_data)
631 return (FC_TARGET_RETURN);
632 } /* }}} int fc_bit_return_invoke */
634 static int fc_bit_write_create (const oconfig_item_t *ci, /* {{{ */
639 fc_writer_t *plugin_list = NULL;
640 size_t plugin_list_len = 0;
642 for (i = 0; i < ci->children_num; i++)
644 oconfig_item_t *child = ci->children + i;
648 if (strcasecmp ("Plugin", child->key) != 0)
650 ERROR ("Filter subsystem: The built-in target `write' does not "
651 "support the configuration option `%s'.",
656 for (j = 0; j < child->values_num; j++)
660 if (child->values[j].type != OCONFIG_TYPE_STRING)
662 ERROR ("Filter subsystem: Built-in target `write': "
663 "The `Plugin' option accepts only string arguments.");
666 plugin = child->values[j].value.string;
668 temp = (fc_writer_t *) realloc (plugin_list, (plugin_list_len + 2)
669 * (sizeof (*plugin_list)));
672 ERROR ("fc_bit_write_create: realloc failed.");
677 plugin_list[plugin_list_len].plugin = fc_strdup (plugin);
678 if (plugin_list[plugin_list_len].plugin == NULL)
680 ERROR ("fc_bit_write_create: fc_strdup failed.");
683 C_COMPLAIN_INIT (&plugin_list[plugin_list_len].complaint);
685 plugin_list[plugin_list_len].plugin = NULL;
686 } /* for (j = 0; j < child->values_num; j++) */
687 } /* for (i = 0; i < ci->children_num; i++) */
689 *user_data = plugin_list;
692 } /* }}} int fc_bit_write_create */
694 static int fc_bit_write_destroy (void **user_data) /* {{{ */
696 fc_writer_t *plugin_list;
699 if ((user_data == NULL) || (*user_data == NULL))
702 plugin_list = *user_data;
704 for (i = 0; plugin_list[i].plugin != NULL; i++)
705 free (plugin_list[i].plugin);
709 } /* }}} int fc_bit_write_destroy */
711 static int fc_bit_write_invoke (const data_set_t *ds, /* {{{ */
712 value_list_t *vl, notification_meta_t __attribute__((unused)) **meta,
715 fc_writer_t *plugin_list;
719 if (user_data != NULL)
720 plugin_list = *user_data;
722 if ((plugin_list == NULL) || (plugin_list[0].plugin == NULL))
724 static c_complain_t write_complaint = C_COMPLAIN_INIT_STATIC;
726 status = plugin_write (/* plugin = */ NULL, ds, vl);
727 if (status == ENOENT)
729 /* in most cases this is a permanent error, so use the complain
730 * mechanism rather than spamming the logs */
731 c_complain (LOG_INFO, &write_complaint,
732 "Filter subsystem: Built-in target `write': Dispatching value to "
733 "all write plugins failed with status %i (ENOENT). "
734 "Most likely this means you didn't load any write plugins.",
737 else if (status != 0)
739 /* often, this is a permanent error (e.g. target system unavailable),
740 * so use the complain mechanism rather than spamming the logs */
741 c_complain (LOG_INFO, &write_complaint,
742 "Filter subsystem: Built-in target `write': Dispatching value to "
743 "all write plugins failed with status %i.", status);
747 assert (status == 0);
748 c_release (LOG_INFO, &write_complaint, "Filter subsystem: "
749 "Built-in target `write': Some write plugin is back to normal "
750 "operation. `write' succeeded.");
757 for (i = 0; plugin_list[i].plugin != NULL; i++)
759 status = plugin_write (plugin_list[i].plugin, ds, vl);
762 c_complain (LOG_INFO, &plugin_list[i].complaint,
763 "Filter subsystem: Built-in target `write': Dispatching value to "
764 "the `%s' plugin failed with status %i.",
765 plugin_list[i].plugin, status);
769 c_release (LOG_INFO, &plugin_list[i].complaint,
770 "Filter subsystem: Built-in target `write': Plugin `%s' is back "
771 "to normal operation. `write' succeeded.", plugin_list[i].plugin);
773 } /* for (i = 0; plugin_list[i] != NULL; i++) */
776 return (FC_TARGET_CONTINUE);
777 } /* }}} int fc_bit_write_invoke */
779 static int fc_init_once (void) /* {{{ */
787 memset (&tproc, 0, sizeof (tproc));
788 tproc.create = fc_bit_jump_create;
789 tproc.destroy = fc_bit_jump_destroy;
790 tproc.invoke = fc_bit_jump_invoke;
791 fc_register_target ("jump", tproc);
793 memset (&tproc, 0, sizeof (tproc));
795 tproc.destroy = NULL;
796 tproc.invoke = fc_bit_stop_invoke;
797 fc_register_target ("stop", tproc);
799 memset (&tproc, 0, sizeof (tproc));
801 tproc.destroy = NULL;
802 tproc.invoke = fc_bit_return_invoke;
803 fc_register_target ("return", tproc);
805 memset (&tproc, 0, sizeof (tproc));
806 tproc.create = fc_bit_write_create;
807 tproc.destroy = fc_bit_write_destroy;
808 tproc.invoke = fc_bit_write_invoke;
809 fc_register_target ("write", tproc);
813 } /* }}} int fc_init_once */
818 /* Add a match to list of available matches. */
819 int fc_register_match (const char *name, match_proc_t proc) /* {{{ */
823 DEBUG ("fc_register_match (%s);", name);
825 m = (fc_match_t *) malloc (sizeof (*m));
828 memset (m, 0, sizeof (*m));
830 sstrncpy (m->name, name, sizeof (m->name));
831 memcpy (&m->proc, &proc, sizeof (m->proc));
834 if (match_list_head == NULL)
842 ptr = match_list_head;
843 while (ptr->next != NULL)
850 } /* }}} int fc_register_match */
852 /* Add a target to list of available targets. */
853 int fc_register_target (const char *name, target_proc_t proc) /* {{{ */
857 DEBUG ("fc_register_target (%s);", name);
859 t = (fc_target_t *) malloc (sizeof (*t));
862 memset (t, 0, sizeof (*t));
864 sstrncpy (t->name, name, sizeof (t->name));
865 memcpy (&t->proc, &proc, sizeof (t->proc));
868 if (target_list_head == NULL)
870 target_list_head = t;
876 ptr = target_list_head;
877 while (ptr->next != NULL)
884 } /* }}} int fc_register_target */
886 fc_chain_t *fc_chain_get_by_name (const char *chain_name) /* {{{ */
890 if (chain_name == NULL)
893 for (chain = chain_list_head; chain != NULL; chain = chain->next)
894 if (strcasecmp (chain_name, chain->name) == 0)
898 } /* }}} int fc_chain_get_by_name */
900 int fc_process_chain (const data_set_t *ds, value_list_t *vl, /* {{{ */
910 DEBUG ("fc_process_chain (chain = %s);", chain->name);
912 status = FC_TARGET_CONTINUE;
913 for (rule = chain->rules; rule != NULL; rule = rule->next)
917 if (rule->name[0] != 0)
919 DEBUG ("fc_process_chain (%s): Testing the `%s' rule.",
920 chain->name, rule->name);
923 /* N. B.: rule->matches may be NULL. */
924 for (match = rule->matches; match != NULL; match = match->next)
926 /* FIXME: Pass the meta-data to match targets here (when implemented). */
927 status = (*match->proc.match) (ds, vl, /* meta = */ NULL,
931 WARNING ("fc_process_chain (%s): A match failed.", chain->name);
934 else if (status != FC_MATCH_MATCHES)
938 /* for-loop has been aborted: Either error or no match. */
941 status = FC_TARGET_CONTINUE;
945 if (rule->name[0] != 0)
947 DEBUG ("fc_process_chain (%s): Rule `%s' matches.",
948 chain->name, rule->name);
951 for (target = rule->targets; target != NULL; target = target->next)
953 /* If we get here, all matches have matched the value. Execute the
955 /* FIXME: Pass the meta-data to match targets here (when implemented). */
956 status = (*target->proc.invoke) (ds, vl, /* meta = */ NULL,
960 WARNING ("fc_process_chain (%s): A target failed.", chain->name);
963 else if (status == FC_TARGET_CONTINUE)
965 else if (status == FC_TARGET_STOP)
967 else if (status == FC_TARGET_RETURN)
971 WARNING ("fc_process_chain (%s): Unknown return value "
972 "from target `%s': %i",
973 chain->name, target->name, status);
977 if ((status == FC_TARGET_STOP)
978 || (status == FC_TARGET_RETURN))
980 if (rule->name[0] != 0)
982 DEBUG ("fc_process_chain (%s): Rule `%s' signaled "
984 chain->name, rule->name,
985 (status == FC_TARGET_STOP) ? "stop" : "return");
991 status = FC_TARGET_CONTINUE;
995 if (status == FC_TARGET_STOP)
996 return (FC_TARGET_STOP);
997 else if (status == FC_TARGET_RETURN)
998 return (FC_TARGET_CONTINUE);
1000 /* for-loop has been aborted: A target returned `FC_TARGET_STOP' */
1002 return (FC_TARGET_CONTINUE);
1004 DEBUG ("fc_process_chain (%s): Executing the default targets.",
1007 status = FC_TARGET_CONTINUE;
1008 for (target = chain->targets; target != NULL; target = target->next)
1010 /* If we get here, all matches have matched the value. Execute the
1012 /* FIXME: Pass the meta-data to match targets here (when implemented). */
1013 status = (*target->proc.invoke) (ds, vl, /* meta = */ NULL,
1014 &target->user_data);
1017 WARNING ("fc_process_chain (%s): The default target failed.",
1020 else if (status == FC_TARGET_CONTINUE)
1022 else if (status == FC_TARGET_STOP)
1024 else if (status == FC_TARGET_RETURN)
1028 WARNING ("fc_process_chain (%s): Unknown return value "
1029 "from target `%s': %i",
1030 chain->name, target->name, status);
1034 if ((status == FC_TARGET_STOP)
1035 || (status == FC_TARGET_RETURN))
1037 assert (target != NULL);
1038 DEBUG ("fc_process_chain (%s): Default target `%s' signaled "
1039 "the %s condition.",
1040 chain->name, target->name,
1041 (status == FC_TARGET_STOP) ? "stop" : "return");
1042 if (status == FC_TARGET_STOP)
1043 return (FC_TARGET_STOP);
1045 return (FC_TARGET_CONTINUE);
1048 DEBUG ("fc_process_chain (%s): Signaling `continue' at end of chain.",
1051 return (FC_TARGET_CONTINUE);
1052 } /* }}} int fc_process_chain */
1054 /* Iterate over all rules in the chain and execute all targets for which all
1056 int fc_default_action (const data_set_t *ds, value_list_t *vl) /* {{{ */
1058 /* FIXME: Pass the meta-data to match targets here (when implemented). */
1059 return (fc_bit_write_invoke (ds, vl,
1060 /* meta = */ NULL, /* user_data = */ NULL));
1061 } /* }}} int fc_default_action */
1063 int fc_configure (const oconfig_item_t *ci) /* {{{ */
1070 if (strcasecmp ("Chain", ci->key) == 0)
1071 return (fc_config_add_chain (ci));
1073 WARNING ("Filter subsystem: Unknown top level config option `%s'.",
1077 } /* }}} int fc_configure */
1079 /* vim: set sw=2 sts=2 et fdm=marker : */