2 * collectd - src/filter_chain.h
3 * Copyright (C) 2008,2009 Florian octo Forster
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; only version 2 of the License is applicable.
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 * Florian octo Forster <octo at verplant.org>
23 * First tell the compiler to stick to the C99 and POSIX standards as close as
26 #ifndef __STRICT_ANSI__ /* {{{ */
27 # define __STRICT_ANSI__
30 #ifndef _ISOC99_SOURCE
31 # define _ISOC99_SOURCE
34 #ifdef _POSIX_C_SOURCE
35 # undef _POSIX_C_SOURCE
37 #define _POSIX_C_SOURCE 200112L
40 /* Single UNIX needed for strdup. */
44 #define _XOPEN_SOURCE 500
61 #include "configfile.h"
64 #include "filter_chain.h"
69 /* List of matches, used in fc_rule_t and for the global `match_list_head'
72 typedef struct fc_match_s fc_match_t; /* {{{ */
75 char name[DATA_MAX_NAME_LEN];
81 /* List of targets, used in fc_rule_t and for the global `target_list_head'
84 typedef struct fc_target_s fc_target_t; /* {{{ */
87 char name[DATA_MAX_NAME_LEN];
93 /* List of rules, used in fc_chain_t */
95 typedef struct fc_rule_s fc_rule_t; /* {{{ */
98 char name[DATA_MAX_NAME_LEN];
100 fc_target_t *targets;
104 /* List of chains, used for `chain_list_head' */
105 struct fc_chain_s /* {{{ */
107 char name[DATA_MAX_NAME_LEN];
109 fc_target_t *targets;
116 static fc_match_t *match_list_head;
117 static fc_target_t *target_list_head;
118 static fc_chain_t *chain_list_head;
123 static void fc_free_matches (fc_match_t *m) /* {{{ */
128 if (m->proc.destroy != NULL)
129 (*m->proc.destroy) (&m->user_data);
130 else if (m->user_data != NULL)
132 ERROR ("Filter sybsystem: fc_free_matches: There is user data, but no "
133 "destroy functions has been specified. "
134 "Memory will probably be lost!");
138 fc_free_matches (m->next);
141 } /* }}} void fc_free_matches */
143 static void fc_free_targets (fc_target_t *t) /* {{{ */
148 if (t->proc.destroy != NULL)
149 (*t->proc.destroy) (&t->user_data);
150 else if (t->user_data != NULL)
152 ERROR ("Filter sybsystem: fc_free_targets: There is user data, but no "
153 "destroy functions has been specified. "
154 "Memory will probably be lost!");
158 fc_free_targets (t->next);
161 } /* }}} void fc_free_targets */
163 static void fc_free_rules (fc_rule_t *r) /* {{{ */
168 fc_free_matches (r->matches);
169 fc_free_targets (r->targets);
172 fc_free_rules (r->next);
175 } /* }}} void fc_free_rules */
177 static void fc_free_chains (fc_chain_t *c) /* {{{ */
182 fc_free_rules (c->rules);
183 fc_free_targets (c->targets);
186 fc_free_chains (c->next);
189 } /* }}} void fc_free_chains */
191 static char *fc_strdup (const char *orig) /* {{{ */
199 sz = strlen (orig) + 1;
200 dest = (char *) malloc (sz);
204 memcpy (dest, orig, sz);
207 } /* }}} char *fc_strdup */
212 * The configuration looks somewhat like this:
218 * Type "^mysql_command$"
219 * TypeInstance "^show_"
230 static int fc_config_add_match (fc_match_t **matches_head, /* {{{ */
237 if ((ci->values_num != 1)
238 || (ci->values[0].type != OCONFIG_TYPE_STRING))
240 WARNING ("Filter subsystem: `Match' blocks require "
241 "exactly one string argument.");
245 ptr = match_list_head;
248 if (strcasecmp (ptr->name, ci->values[0].value.string) == 0)
255 WARNING ("Filter subsystem: Cannot find a \"%s\" match. "
256 "Did you load the appropriate plugin?",
257 ci->values[0].value.string);
261 m = (fc_match_t *) malloc (sizeof (*m));
264 ERROR ("fc_config_add_match: malloc failed.");
267 memset (m, 0, sizeof (*m));
269 sstrncpy (m->name, ptr->name, sizeof (m->name));
270 memcpy (&m->proc, &ptr->proc, sizeof (m->proc));
271 assert (m->proc.create != NULL);
275 status = (*m->proc.create) (ci, &m->user_data);
278 WARNING ("Filter subsystem: Failed to create a %s match.",
284 if (*matches_head != NULL)
287 while (ptr->next != NULL)
298 } /* }}} int fc_config_add_match */
300 static int fc_config_add_target (fc_target_t **targets_head, /* {{{ */
307 if ((ci->values_num != 1)
308 || (ci->values[0].type != OCONFIG_TYPE_STRING))
310 WARNING ("Filter subsystem: `Target' blocks require "
311 "exactly one string argument.");
315 ptr = target_list_head;
318 if (strcasecmp (ptr->name, ci->values[0].value.string) == 0)
325 WARNING ("Filter subsystem: Cannot find a \"%s\" target. "
326 "Did you load the appropriate plugin?",
327 ci->values[0].value.string);
331 t = (fc_target_t *) malloc (sizeof (*t));
334 ERROR ("fc_config_add_match: malloc failed.");
337 memset (t, 0, sizeof (*t));
339 sstrncpy (t->name, ptr->name, sizeof (t->name));
340 memcpy (&t->proc, &ptr->proc, sizeof (t->proc));
344 if (t->proc.create != NULL)
346 status = (*t->proc.create) (ci, &t->user_data);
349 WARNING ("Filter subsystem: Failed to create a %s match.",
360 if (*targets_head != NULL)
363 while (ptr->next != NULL)
374 } /* }}} int fc_config_add_target */
376 static int fc_config_add_rule (fc_chain_t *chain, /* {{{ */
380 char rule_name[2*DATA_MAX_NAME_LEN] = "Unnamed rule";
384 if (ci->values_num > 1)
386 WARNING ("Filter subsystem: `Rule' blocks have at most one argument.");
389 else if ((ci->values_num == 1)
390 && (ci->values[0].type != OCONFIG_TYPE_STRING))
392 WARNING ("Filter subsystem: `Rule' blocks expect one string argument "
393 "or no argument at all.");
397 rule = (fc_rule_t *) malloc (sizeof (*rule));
400 ERROR ("fc_config_add_rule: malloc failed.");
403 memset (rule, 0, sizeof (*rule));
406 if (ci->values_num == 1)
408 sstrncpy (rule->name, ci->values[0].value.string, sizeof (rule->name));
409 ssnprintf (rule_name, sizeof (rule_name), "Rule \"%s\"",
410 ci->values[0].value.string);
413 for (i = 0; i < ci->children_num; i++)
415 oconfig_item_t *option = ci->children + i;
418 if (strcasecmp ("Match", option->key) == 0)
419 status = fc_config_add_match (&rule->matches, option);
420 else if (strcasecmp ("Target", option->key) == 0)
421 status = fc_config_add_target (&rule->targets, option);
424 WARNING ("Filter subsystem: %s: Option `%s' not allowed "
425 "inside a <Rule> block.", rule_name, option->key);
431 } /* for (ci->children) */
433 /* Additional sanity checking. */
436 if (rule->targets == NULL)
438 WARNING ("Filter subsystem: %s: No target has been specified.",
445 } /* while (status == 0) */
449 fc_free_rules (rule);
453 if (chain->rules != NULL)
458 while (ptr->next != NULL)
469 } /* }}} int fc_config_add_rule */
471 static int fc_config_add_chain (const oconfig_item_t *ci) /* {{{ */
477 if ((ci->values_num != 1)
478 || (ci->values[0].type != OCONFIG_TYPE_STRING))
480 WARNING ("Filter subsystem: <Chain> blocks require exactly one "
485 chain = (fc_chain_t *) malloc (sizeof (*chain));
488 ERROR ("fc_config_add_chain: malloc failed.");
491 memset (chain, 0, sizeof (*chain));
492 sstrncpy (chain->name, ci->values[0].value.string, sizeof (chain->name));
494 chain->targets = NULL;
497 for (i = 0; i < ci->children_num; i++)
499 oconfig_item_t *option = ci->children + i;
502 if (strcasecmp ("Rule", option->key) == 0)
503 status = fc_config_add_rule (chain, option);
504 else if (strcasecmp ("Target", option->key) == 0)
505 status = fc_config_add_target (&chain->targets, option);
508 WARNING ("Filter subsystem: Chain %s: Option `%s' not allowed "
509 "inside a <Chain> block.", chain->name, option->key);
515 } /* for (ci->children) */
517 /* Additional sanity checking. */
520 if (chain->targets == NULL)
522 WARNING ("Filter subsystem: Chain %s: No default target has been "
523 "specified. Please make sure that there is a <Target> block within "
524 "the <Chain> block!", chain->name);
530 } /* while (status == 0) */
534 fc_free_chains (chain);
538 if (chain_list_head != NULL)
542 ptr = chain_list_head;
543 while (ptr->next != NULL)
550 chain_list_head = chain;
554 } /* }}} int fc_config_add_chain */
557 * Built-in target "jump"
559 * Prefix `bit' like `_b_uilt-_i_n _t_arget'
561 static int fc_bit_jump_create (const oconfig_item_t *ci, /* {{{ */
564 oconfig_item_t *ci_chain;
566 if (ci->children_num != 1)
568 ERROR ("Filter subsystem: The built-in target `jump' needs exactly "
569 "one `Chain' argument!");
573 ci_chain = ci->children;
574 if (strcasecmp ("Chain", ci_chain->key) != 0)
576 ERROR ("Filter subsystem: The built-in target `jump' does not "
577 "support the configuration option `%s'.",
582 if ((ci_chain->values_num != 1)
583 || (ci_chain->values[0].type != OCONFIG_TYPE_STRING))
585 ERROR ("Filter subsystem: Built-in target `jump': The `Chain' option "
586 "needs exactly one string argument.");
590 *user_data = fc_strdup (ci_chain->values[0].value.string);
591 if (*user_data == NULL)
593 ERROR ("fc_bit_jump_create: fc_strdup failed.");
598 } /* }}} int fc_bit_jump_create */
600 static int fc_bit_jump_destroy (void **user_data) /* {{{ */
602 if (user_data != NULL)
609 } /* }}} int fc_bit_jump_destroy */
611 static int fc_bit_jump_invoke (const data_set_t *ds, /* {{{ */
612 value_list_t *vl, notification_meta_t __attribute__((unused)) **meta,
619 chain_name = *user_data;
621 for (chain = chain_list_head; chain != NULL; chain = chain->next)
622 if (strcasecmp (chain_name, chain->name) == 0)
627 ERROR ("Filter subsystem: Built-in target `jump': There is no chain "
628 "named `%s'.", chain_name);
632 status = fc_process_chain (ds, vl, chain);
635 else if (status == FC_TARGET_STOP)
636 return (FC_TARGET_STOP);
638 return (FC_TARGET_CONTINUE);
639 } /* }}} int fc_bit_jump_invoke */
641 static int fc_bit_stop_invoke (const data_set_t __attribute__((unused)) *ds, /* {{{ */
642 value_list_t __attribute__((unused)) *vl,
643 notification_meta_t __attribute__((unused)) **meta,
644 void __attribute__((unused)) **user_data)
646 return (FC_TARGET_STOP);
647 } /* }}} int fc_bit_stop_invoke */
649 static int fc_bit_return_invoke (const data_set_t __attribute__((unused)) *ds, /* {{{ */
650 value_list_t __attribute__((unused)) *vl,
651 notification_meta_t __attribute__((unused)) **meta,
652 void __attribute__((unused)) **user_data)
654 return (FC_TARGET_RETURN);
655 } /* }}} int fc_bit_return_invoke */
657 static int fc_bit_write_create (const oconfig_item_t *ci, /* {{{ */
663 size_t plugin_list_len;
668 for (i = 0; i < ci->children_num; i++)
670 oconfig_item_t *child = ci->children + i;
674 if (strcasecmp ("Plugin", child->key) != 0)
676 ERROR ("Filter subsystem: The built-in target `write' does not "
677 "support the configuration option `%s'.",
682 for (j = 0; j < child->values_num; j++)
684 if (child->values[j].type != OCONFIG_TYPE_STRING)
686 ERROR ("Filter subsystem: Built-in target `write': "
687 "The `Plugin' option accepts only string arguments.");
691 temp = (char **) realloc (plugin_list, (plugin_list_len + 2)
692 * (sizeof (*plugin_list)));
695 ERROR ("fc_bit_write_create: realloc failed.");
700 plugin_list[plugin_list_len] = fc_strdup (child->values[j].value.string);
701 if (plugin_list[plugin_list_len] == NULL)
703 ERROR ("fc_bit_write_create: fc_strdup failed.");
707 plugin_list[plugin_list_len] = NULL;
708 } /* for (j = 0; j < child->values_num; j++) */
709 } /* for (i = 0; i < ci->children_num; i++) */
711 *user_data = plugin_list;
714 } /* }}} int fc_bit_write_create */
716 static int fc_bit_write_destroy (void **user_data) /* {{{ */
721 if ((user_data == NULL) || (*user_data == NULL))
724 plugin_list = *user_data;
726 for (i = 0; plugin_list[i] != NULL; i++)
727 free (plugin_list[i]);
731 } /* }}} int fc_bit_write_destroy */
733 static int fc_bit_write_invoke (const data_set_t *ds, /* {{{ */
734 value_list_t *vl, notification_meta_t __attribute__((unused)) **meta,
741 if (user_data != NULL)
742 plugin_list = *user_data;
744 if ((plugin_list == NULL) || (plugin_list[0] == NULL))
746 status = plugin_write (/* plugin = */ NULL, ds, vl);
749 INFO ("Filter subsystem: Built-in target `write': Dispatching value to "
750 "all write plugins failed with status %i.", status);
757 for (i = 0; plugin_list[i] != NULL; i++)
759 status = plugin_write (plugin_list[i], ds, vl);
762 INFO ("Filter subsystem: Built-in target `write': Dispatching value to "
763 "the `%s' plugin failed with status %i.", plugin_list[i], status);
765 } /* for (i = 0; plugin_list[i] != NULL; i++) */
768 return (FC_TARGET_CONTINUE);
769 } /* }}} int fc_bit_write_invoke */
771 static int fc_init_once (void) /* {{{ */
779 memset (&tproc, 0, sizeof (tproc));
780 tproc.create = fc_bit_jump_create;
781 tproc.destroy = fc_bit_jump_destroy;
782 tproc.invoke = fc_bit_jump_invoke;
783 fc_register_target ("jump", tproc);
785 memset (&tproc, 0, sizeof (tproc));
787 tproc.destroy = NULL;
788 tproc.invoke = fc_bit_stop_invoke;
789 fc_register_target ("stop", tproc);
791 memset (&tproc, 0, sizeof (tproc));
793 tproc.destroy = NULL;
794 tproc.invoke = fc_bit_return_invoke;
795 fc_register_target ("return", tproc);
797 memset (&tproc, 0, sizeof (tproc));
798 tproc.create = fc_bit_write_create;
799 tproc.destroy = fc_bit_write_destroy;
800 tproc.invoke = fc_bit_write_invoke;
801 fc_register_target ("write", tproc);
805 } /* }}} int fc_init_once */
810 /* Add a match to list of available matches. */
811 int fc_register_match (const char *name, match_proc_t proc) /* {{{ */
815 DEBUG ("fc_register_match (%s);", name);
817 m = (fc_match_t *) malloc (sizeof (*m));
820 memset (m, 0, sizeof (*m));
822 sstrncpy (m->name, name, sizeof (m->name));
823 memcpy (&m->proc, &proc, sizeof (m->proc));
826 if (match_list_head == NULL)
834 ptr = match_list_head;
835 while (ptr->next != NULL)
842 } /* }}} int fc_register_match */
844 /* Add a target to list of available targets. */
845 int fc_register_target (const char *name, target_proc_t proc) /* {{{ */
849 DEBUG ("fc_register_target (%s);", name);
851 t = (fc_target_t *) malloc (sizeof (*t));
854 memset (t, 0, sizeof (*t));
856 sstrncpy (t->name, name, sizeof (t->name));
857 memcpy (&t->proc, &proc, sizeof (t->proc));
860 if (target_list_head == NULL)
862 target_list_head = t;
868 ptr = target_list_head;
869 while (ptr->next != NULL)
876 } /* }}} int fc_register_target */
878 fc_chain_t *fc_chain_get_by_name (const char *chain_name) /* {{{ */
882 if (chain_name == NULL)
885 for (chain = chain_list_head; chain != NULL; chain = chain->next)
886 if (strcasecmp (chain_name, chain->name) == 0)
890 } /* }}} int fc_chain_get_by_name */
892 int fc_process_chain (const data_set_t *ds, value_list_t *vl, /* {{{ */
902 DEBUG ("fc_process_chain (chain = %s);", chain->name);
904 status = FC_TARGET_CONTINUE;
905 for (rule = chain->rules; rule != NULL; rule = rule->next)
909 if (rule->name[0] != 0)
911 DEBUG ("fc_process_chain (%s): Testing the `%s' rule.",
912 chain->name, rule->name);
915 /* N. B.: rule->matches may be NULL. */
916 for (match = rule->matches; match != NULL; match = match->next)
918 /* FIXME: Pass the meta-data to match targets here (when implemented). */
919 status = (*match->proc.match) (ds, vl, /* meta = */ NULL,
923 WARNING ("fc_process_chain (%s): A match failed.", chain->name);
926 else if (status != FC_MATCH_MATCHES)
930 /* for-loop has been aborted: Either error or no match. */
933 status = FC_TARGET_CONTINUE;
937 if (rule->name[0] != 0)
939 DEBUG ("fc_process_chain (%s): Rule `%s' matches.",
940 chain->name, rule->name);
943 for (target = rule->targets; target != NULL; target = target->next)
945 /* If we get here, all matches have matched the value. Execute the
947 /* FIXME: Pass the meta-data to match targets here (when implemented). */
948 status = (*target->proc.invoke) (ds, vl, /* meta = */ NULL,
952 WARNING ("fc_process_chain (%s): A target failed.", chain->name);
955 else if (status == FC_TARGET_CONTINUE)
957 else if (status == FC_TARGET_STOP)
959 else if (status == FC_TARGET_RETURN)
963 WARNING ("fc_process_chain (%s): Unknown return value "
964 "from target `%s': %i",
965 chain->name, target->name, status);
969 if ((status == FC_TARGET_STOP)
970 || (status == FC_TARGET_RETURN))
972 if (rule->name[0] != 0)
974 DEBUG ("fc_process_chain (%s): Rule `%s' signaled "
976 chain->name, rule->name,
977 (status == FC_TARGET_STOP) ? "stop" : "return");
983 status = FC_TARGET_CONTINUE;
987 if (status == FC_TARGET_STOP)
988 return (FC_TARGET_STOP);
989 else if (status == FC_TARGET_RETURN)
990 return (FC_TARGET_CONTINUE);
992 /* for-loop has been aborted: A target returned `FC_TARGET_STOP' */
994 return (FC_TARGET_CONTINUE);
996 DEBUG ("fc_process_chain (%s): Executing the default targets.",
999 status = FC_TARGET_CONTINUE;
1000 for (target = chain->targets; target != NULL; target = target->next)
1002 /* If we get here, all matches have matched the value. Execute the
1004 /* FIXME: Pass the meta-data to match targets here (when implemented). */
1005 status = (*target->proc.invoke) (ds, vl, /* meta = */ NULL,
1006 &target->user_data);
1009 WARNING ("fc_process_chain (%s): The default target failed.",
1012 else if (status == FC_TARGET_CONTINUE)
1014 else if (status == FC_TARGET_STOP)
1016 else if (status == FC_TARGET_RETURN)
1020 WARNING ("fc_process_chain (%s): Unknown return value "
1021 "from target `%s': %i",
1022 chain->name, target->name, status);
1026 if ((status == FC_TARGET_STOP)
1027 || (status == FC_TARGET_RETURN))
1029 assert (target != NULL);
1030 DEBUG ("fc_process_chain (%s): Default target `%s' signaled "
1031 "the %s condition.",
1032 chain->name, target->name,
1033 (status == FC_TARGET_STOP) ? "stop" : "return");
1034 if (status == FC_TARGET_STOP)
1035 return (FC_TARGET_STOP);
1037 return (FC_TARGET_CONTINUE);
1040 DEBUG ("fc_process_chain (%s): Signaling `continue' at end of chain.",
1043 return (FC_TARGET_CONTINUE);
1044 } /* }}} int fc_process_chain */
1046 /* Iterate over all rules in the chain and execute all targets for which all
1048 int fc_default_action (const data_set_t *ds, value_list_t *vl) /* {{{ */
1050 /* FIXME: Pass the meta-data to match targets here (when implemented). */
1051 return (fc_bit_write_invoke (ds, vl,
1052 /* meta = */ NULL, /* user_data = */ NULL));
1053 } /* }}} int fc_default_action */
1055 int fc_configure (const oconfig_item_t *ci) /* {{{ */
1062 if (strcasecmp ("Chain", ci->key) == 0)
1063 return (fc_config_add_chain (ci));
1065 WARNING ("Filter subsystem: Unknown top level config option `%s'.",
1069 } /* }}} int fc_configure */
1071 /* vim: set sw=2 sts=2 et fdm=marker : */