--- /dev/null
- status = 0;
+/**
+ * collectd - src/filter_chain.c
+ * Copyright (C) 2008-2010 Florian octo Forster
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Authors:
+ * Florian octo Forster <octo at collectd.org>
+ **/
+
+#include "collectd.h"
+#include "configfile.h"
+#include "plugin.h"
+#include "utils_complain.h"
+#include "common.h"
+#include "filter_chain.h"
+
+/*
+ * Data types
+ */
+/* List of matches, used in fc_rule_t and for the global `match_list_head'
+ * variable. */
+struct fc_match_s;
+typedef struct fc_match_s fc_match_t; /* {{{ */
+struct fc_match_s
+{
+ char name[DATA_MAX_NAME_LEN];
+ match_proc_t proc;
+ void *user_data;
+ fc_match_t *next;
+}; /* }}} */
+
+/* List of targets, used in fc_rule_t and for the global `target_list_head'
+ * variable. */
+struct fc_target_s;
+typedef struct fc_target_s fc_target_t; /* {{{ */
+struct fc_target_s
+{
+ char name[DATA_MAX_NAME_LEN];
+ void *user_data;
+ target_proc_t proc;
+ fc_target_t *next;
+}; /* }}} */
+
+/* List of rules, used in fc_chain_t */
+struct fc_rule_s;
+typedef struct fc_rule_s fc_rule_t; /* {{{ */
+struct fc_rule_s
+{
+ char name[DATA_MAX_NAME_LEN];
+ fc_match_t *matches;
+ fc_target_t *targets;
+ fc_rule_t *next;
+}; /* }}} */
+
+/* List of chains, used for `chain_list_head' */
+struct fc_chain_s /* {{{ */
+{
+ char name[DATA_MAX_NAME_LEN];
+ fc_rule_t *rules;
+ fc_target_t *targets;
+ fc_chain_t *next;
+}; /* }}} */
+
+/* Writer configuration. */
+struct fc_writer_s;
+typedef struct fc_writer_s fc_writer_t; /* {{{ */
+struct fc_writer_s
+{
+ char *plugin;
+ c_complain_t complaint;
+}; /* }}} */
+
+/*
+ * Global variables
+ */
+static fc_match_t *match_list_head;
+static fc_target_t *target_list_head;
+static fc_chain_t *chain_list_head;
+
+/*
+ * Private functions
+ */
+static void fc_free_matches (fc_match_t *m) /* {{{ */
+{
+ if (m == NULL)
+ return;
+
+ if (m->proc.destroy != NULL)
+ (*m->proc.destroy) (&m->user_data);
+ else if (m->user_data != NULL)
+ {
+ ERROR ("Filter subsystem: fc_free_matches: There is user data, but no "
+ "destroy functions has been specified. "
+ "Memory will probably be lost!");
+ }
+
+ if (m->next != NULL)
+ fc_free_matches (m->next);
+
+ free (m);
+} /* }}} void fc_free_matches */
+
+static void fc_free_targets (fc_target_t *t) /* {{{ */
+{
+ if (t == NULL)
+ return;
+
+ if (t->proc.destroy != NULL)
+ (*t->proc.destroy) (&t->user_data);
+ else if (t->user_data != NULL)
+ {
+ ERROR ("Filter subsystem: fc_free_targets: There is user data, but no "
+ "destroy functions has been specified. "
+ "Memory will probably be lost!");
+ }
+
+ if (t->next != NULL)
+ fc_free_targets (t->next);
+
+ free (t);
+} /* }}} void fc_free_targets */
+
+static void fc_free_rules (fc_rule_t *r) /* {{{ */
+{
+ if (r == NULL)
+ return;
+
+ fc_free_matches (r->matches);
+ fc_free_targets (r->targets);
+
+ if (r->next != NULL)
+ fc_free_rules (r->next);
+
+ free (r);
+} /* }}} void fc_free_rules */
+
+static void fc_free_chains (fc_chain_t *c) /* {{{ */
+{
+ if (c == NULL)
+ return;
+
+ fc_free_rules (c->rules);
+ fc_free_targets (c->targets);
+
+ if (c->next != NULL)
+ fc_free_chains (c->next);
+
+ free (c);
+} /* }}} void fc_free_chains */
+
+static char *fc_strdup (const char *orig) /* {{{ */
+{
+ size_t sz;
+ char *dest;
+
+ if (orig == NULL)
+ return (NULL);
+
+ sz = strlen (orig) + 1;
+ dest = (char *) malloc (sz);
+ if (dest == NULL)
+ return (NULL);
+
+ memcpy (dest, orig, sz);
+
+ return (dest);
+} /* }}} char *fc_strdup */
+
+/*
+ * Configuration.
+ *
+ * The configuration looks somewhat like this:
+ *
+ * <Chain "PreCache">
+ * <Rule>
+ * <Match "regex">
+ * Plugin "^mysql$"
+ * Type "^mysql_command$"
+ * TypeInstance "^show_"
+ * </Match>
+ * <Target "drop">
+ * </Target>
+ * </Rule>
+ *
+ * <Target "write">
+ * Plugin "rrdtool"
+ * </Target>
+ * </Chain>
+ */
+static int fc_config_add_match (fc_match_t **matches_head, /* {{{ */
+ oconfig_item_t *ci)
+{
+ fc_match_t *m;
+ fc_match_t *ptr;
+ int status;
+
+ if ((ci->values_num != 1)
+ || (ci->values[0].type != OCONFIG_TYPE_STRING))
+ {
+ WARNING ("Filter subsystem: `Match' blocks require "
+ "exactly one string argument.");
+ return (-1);
+ }
+
+ ptr = match_list_head;
+ while (ptr != NULL)
+ {
+ if (strcasecmp (ptr->name, ci->values[0].value.string) == 0)
+ break;
+ ptr = ptr->next;
+ }
+
+ if (ptr == NULL)
+ {
+ WARNING ("Filter subsystem: Cannot find a \"%s\" match. "
+ "Did you load the appropriate plugin?",
+ ci->values[0].value.string);
+ return (-1);
+ }
+
+ m = (fc_match_t *) malloc (sizeof (*m));
+ if (m == NULL)
+ {
+ ERROR ("fc_config_add_match: malloc failed.");
+ return (-1);
+ }
+ memset (m, 0, sizeof (*m));
+
+ sstrncpy (m->name, ptr->name, sizeof (m->name));
+ memcpy (&m->proc, &ptr->proc, sizeof (m->proc));
+ m->user_data = NULL;
+ m->next = NULL;
+
+ if (m->proc.create != NULL)
+ {
+ status = (*m->proc.create) (ci, &m->user_data);
+ if (status != 0)
+ {
+ WARNING ("Filter subsystem: Failed to create a %s match.",
+ m->name);
+ fc_free_matches (m);
+ return (-1);
+ }
+ }
+
+ if (*matches_head != NULL)
+ {
+ ptr = *matches_head;
+ while (ptr->next != NULL)
+ ptr = ptr->next;
+
+ ptr->next = m;
+ }
+ else
+ {
+ *matches_head = m;
+ }
+
+ return (0);
+} /* }}} int fc_config_add_match */
+
+static int fc_config_add_target (fc_target_t **targets_head, /* {{{ */
+ oconfig_item_t *ci)
+{
+ fc_target_t *t;
+ fc_target_t *ptr;
+ int status;
+
+ if ((ci->values_num != 1)
+ || (ci->values[0].type != OCONFIG_TYPE_STRING))
+ {
+ WARNING ("Filter subsystem: `Target' blocks require "
+ "exactly one string argument.");
+ return (-1);
+ }
+
+ ptr = target_list_head;
+ while (ptr != NULL)
+ {
+ if (strcasecmp (ptr->name, ci->values[0].value.string) == 0)
+ break;
+ ptr = ptr->next;
+ }
+
+ if (ptr == NULL)
+ {
+ WARNING ("Filter subsystem: Cannot find a \"%s\" target. "
+ "Did you load the appropriate plugin?",
+ ci->values[0].value.string);
+ return (-1);
+ }
+
+ t = (fc_target_t *) malloc (sizeof (*t));
+ if (t == NULL)
+ {
+ ERROR ("fc_config_add_target: malloc failed.");
+ return (-1);
+ }
+ memset (t, 0, sizeof (*t));
+
+ sstrncpy (t->name, ptr->name, sizeof (t->name));
+ memcpy (&t->proc, &ptr->proc, sizeof (t->proc));
+ t->user_data = NULL;
+ t->next = NULL;
+
+ if (t->proc.create != NULL)
+ {
+ status = (*t->proc.create) (ci, &t->user_data);
+ if (status != 0)
+ {
+ WARNING ("Filter subsystem: Failed to create a %s target.",
+ t->name);
+ fc_free_targets (t);
+ return (-1);
+ }
+ }
+ else
+ {
+ t->user_data = NULL;
+ }
+
+ if (*targets_head != NULL)
+ {
+ ptr = *targets_head;
+ while (ptr->next != NULL)
+ ptr = ptr->next;
+
+ ptr->next = t;
+ }
+ else
+ {
+ *targets_head = t;
+ }
+
+ return (0);
+} /* }}} int fc_config_add_target */
+
+static int fc_config_add_rule (fc_chain_t *chain, /* {{{ */
+ oconfig_item_t *ci)
+{
+ fc_rule_t *rule;
+ char rule_name[2*DATA_MAX_NAME_LEN] = "Unnamed rule";
+ int status = 0;
+ int i;
+
+ if (ci->values_num > 1)
+ {
+ WARNING ("Filter subsystem: `Rule' blocks have at most one argument.");
+ return (-1);
+ }
+ else if ((ci->values_num == 1)
+ && (ci->values[0].type != OCONFIG_TYPE_STRING))
+ {
+ WARNING ("Filter subsystem: `Rule' blocks expect one string argument "
+ "or no argument at all.");
+ return (-1);
+ }
+
+ rule = (fc_rule_t *) malloc (sizeof (*rule));
+ if (rule == NULL)
+ {
+ ERROR ("fc_config_add_rule: malloc failed.");
+ return (-1);
+ }
+ memset (rule, 0, sizeof (*rule));
+ rule->next = NULL;
+
+ if (ci->values_num == 1)
+ {
+ sstrncpy (rule->name, ci->values[0].value.string, sizeof (rule->name));
+ ssnprintf (rule_name, sizeof (rule_name), "Rule \"%s\"",
+ ci->values[0].value.string);
+ }
+
+ for (i = 0; i < ci->children_num; i++)
+ {
+ oconfig_item_t *option = ci->children + i;
- status = 0;
+
+ if (strcasecmp ("Match", option->key) == 0)
+ status = fc_config_add_match (&rule->matches, option);
+ else if (strcasecmp ("Target", option->key) == 0)
+ status = fc_config_add_target (&rule->targets, option);
+ else
+ {
+ WARNING ("Filter subsystem: %s: Option `%s' not allowed "
+ "inside a <Rule> block.", rule_name, option->key);
+ status = -1;
+ }
+
+ if (status != 0)
+ break;
+ } /* for (ci->children) */
+
+ /* Additional sanity checking. */
+ while (status == 0)
+ {
+ if (rule->targets == NULL)
+ {
+ WARNING ("Filter subsystem: %s: No target has been specified.",
+ rule_name);
+ status = -1;
+ break;
+ }
+
+ break;
+ } /* while (status == 0) */
+
+ if (status != 0)
+ {
+ fc_free_rules (rule);
+ return (-1);
+ }
+
+ if (chain->rules != NULL)
+ {
+ fc_rule_t *ptr;
+
+ ptr = chain->rules;
+ while (ptr->next != NULL)
+ ptr = ptr->next;
+
+ ptr->next = rule;
+ }
+ else
+ {
+ chain->rules = rule;
+ }
+
+ return (0);
+} /* }}} int fc_config_add_rule */
+
+static int fc_config_add_chain (const oconfig_item_t *ci) /* {{{ */
+{
+ fc_chain_t *chain = NULL;
+ int status = 0;
+ int i;
+ int new_chain = 1;
+
+ if ((ci->values_num != 1)
+ || (ci->values[0].type != OCONFIG_TYPE_STRING))
+ {
+ WARNING ("Filter subsystem: <Chain> blocks require exactly one "
+ "string argument.");
+ return (-1);
+ }
+
+ if (chain_list_head != NULL)
+ {
+ if ((chain = fc_chain_get_by_name (ci->values[0].value.string)) != NULL)
+ new_chain = 0;
+ }
+
+ if (chain == NULL)
+ {
+ chain = (fc_chain_t *) malloc (sizeof (*chain));
+ if (chain == NULL)
+ {
+ ERROR ("fc_config_add_chain: malloc failed.");
+ return (-1);
+ }
+ memset (chain, 0, sizeof (*chain));
+ sstrncpy (chain->name, ci->values[0].value.string, sizeof (chain->name));
+ chain->rules = NULL;
+ chain->targets = NULL;
+ chain->next = NULL;
+ }
+
+ for (i = 0; i < ci->children_num; i++)
+ {
+ oconfig_item_t *option = ci->children + i;
+
+ if (strcasecmp ("Rule", option->key) == 0)
+ status = fc_config_add_rule (chain, option);
+ else if (strcasecmp ("Target", option->key) == 0)
+ status = fc_config_add_target (&chain->targets, option);
+ else
+ {
+ WARNING ("Filter subsystem: Chain %s: Option `%s' not allowed "
+ "inside a <Chain> block.", chain->name, option->key);
+ status = -1;
+ }
+
+ if (status != 0)
+ break;
+ } /* for (ci->children) */
+
+ if (status != 0)
+ {
+ fc_free_chains (chain);
+ return (-1);
+ }
+
+ if (chain_list_head != NULL)
+ {
+ if (!new_chain)
+ return (0);
+
+ fc_chain_t *ptr;
+
+ ptr = chain_list_head;
+ while (ptr->next != NULL)
+ ptr = ptr->next;
+
+ ptr->next = chain;
+ }
+ else
+ {
+ chain_list_head = chain;
+ }
+
+ return (0);
+} /* }}} int fc_config_add_chain */
+
+/*
+ * Built-in target "jump"
+ *
+ * Prefix `bit' like `_b_uilt-_i_n _t_arget'
+ */
+static int fc_bit_jump_create (const oconfig_item_t *ci, /* {{{ */
+ void **user_data)
+{
+ oconfig_item_t *ci_chain;
+
+ if (ci->children_num != 1)
+ {
+ ERROR ("Filter subsystem: The built-in target `jump' needs exactly "
+ "one `Chain' argument!");
+ return (-1);
+ }
+
+ ci_chain = ci->children;
+ if (strcasecmp ("Chain", ci_chain->key) != 0)
+ {
+ ERROR ("Filter subsystem: The built-in target `jump' does not "
+ "support the configuration option `%s'.",
+ ci_chain->key);
+ return (-1);
+ }
+
+ if ((ci_chain->values_num != 1)
+ || (ci_chain->values[0].type != OCONFIG_TYPE_STRING))
+ {
+ ERROR ("Filter subsystem: Built-in target `jump': The `Chain' option "
+ "needs exactly one string argument.");
+ return (-1);
+ }
+
+ *user_data = fc_strdup (ci_chain->values[0].value.string);
+ if (*user_data == NULL)
+ {
+ ERROR ("fc_bit_jump_create: fc_strdup failed.");
+ return (-1);
+ }
+
+ return (0);
+} /* }}} int fc_bit_jump_create */
+
+static int fc_bit_jump_destroy (void **user_data) /* {{{ */
+{
+ if (user_data != NULL)
+ {
+ free (*user_data);
+ *user_data = NULL;
+ }
+
+ return (0);
+} /* }}} int fc_bit_jump_destroy */
+
+static int fc_bit_jump_invoke (const data_set_t *ds, /* {{{ */
+ value_list_t *vl, notification_meta_t __attribute__((unused)) **meta,
+ void **user_data)
+{
+ char *chain_name;
+ fc_chain_t *chain;
+ int status;
+
+ chain_name = *user_data;
+
+ for (chain = chain_list_head; chain != NULL; chain = chain->next)
+ if (strcasecmp (chain_name, chain->name) == 0)
+ break;
+
+ if (chain == NULL)
+ {
+ ERROR ("Filter subsystem: Built-in target `jump': There is no chain "
+ "named `%s'.", chain_name);
+ return (-1);
+ }
+
+ status = fc_process_chain (ds, vl, chain);
+ if (status < 0)
+ return (status);
+ else if (status == FC_TARGET_STOP)
+ return (FC_TARGET_STOP);
+ else
+ return (FC_TARGET_CONTINUE);
+} /* }}} int fc_bit_jump_invoke */
+
+static int fc_bit_stop_invoke (const data_set_t __attribute__((unused)) *ds, /* {{{ */
+ value_list_t __attribute__((unused)) *vl,
+ notification_meta_t __attribute__((unused)) **meta,
+ void __attribute__((unused)) **user_data)
+{
+ return (FC_TARGET_STOP);
+} /* }}} int fc_bit_stop_invoke */
+
+static int fc_bit_return_invoke (const data_set_t __attribute__((unused)) *ds, /* {{{ */
+ value_list_t __attribute__((unused)) *vl,
+ notification_meta_t __attribute__((unused)) **meta,
+ void __attribute__((unused)) **user_data)
+{
+ return (FC_TARGET_RETURN);
+} /* }}} int fc_bit_return_invoke */
+
+static int fc_bit_write_create (const oconfig_item_t *ci, /* {{{ */
+ void **user_data)
+{
+ int i;
+
+ fc_writer_t *plugin_list = NULL;
+ size_t plugin_list_len = 0;
+
+ for (i = 0; i < ci->children_num; i++)
+ {
+ oconfig_item_t *child = ci->children + i;
+ fc_writer_t *temp;
+ int j;
+
+ if (strcasecmp ("Plugin", child->key) != 0)
+ {
+ ERROR ("Filter subsystem: The built-in target `write' does not "
+ "support the configuration option `%s'.",
+ child->key);
+ continue;
+ }
+
+ for (j = 0; j < child->values_num; j++)
+ {
+ char *plugin;
+
+ if (child->values[j].type != OCONFIG_TYPE_STRING)
+ {
+ ERROR ("Filter subsystem: Built-in target `write': "
+ "The `Plugin' option accepts only string arguments.");
+ continue;
+ }
+ plugin = child->values[j].value.string;
+
+ temp = (fc_writer_t *) realloc (plugin_list, (plugin_list_len + 2)
+ * (sizeof (*plugin_list)));
+ if (temp == NULL)
+ {
+ ERROR ("fc_bit_write_create: realloc failed.");
+ continue;
+ }
+ plugin_list = temp;
+
+ plugin_list[plugin_list_len].plugin = fc_strdup (plugin);
+ if (plugin_list[plugin_list_len].plugin == NULL)
+ {
+ ERROR ("fc_bit_write_create: fc_strdup failed.");
+ continue;
+ }
+ C_COMPLAIN_INIT (&plugin_list[plugin_list_len].complaint);
+ plugin_list_len++;
+ plugin_list[plugin_list_len].plugin = NULL;
+ } /* for (j = 0; j < child->values_num; j++) */
+ } /* for (i = 0; i < ci->children_num; i++) */
+
+ *user_data = plugin_list;
+
+ return (0);
+} /* }}} int fc_bit_write_create */
+
+static int fc_bit_write_destroy (void **user_data) /* {{{ */
+{
+ fc_writer_t *plugin_list;
+ size_t i;
+
+ if ((user_data == NULL) || (*user_data == NULL))
+ return (0);
+
+ plugin_list = *user_data;
+
+ for (i = 0; plugin_list[i].plugin != NULL; i++)
+ free (plugin_list[i].plugin);
+ free (plugin_list);
+
+ return (0);
+} /* }}} int fc_bit_write_destroy */
+
+static int fc_bit_write_invoke (const data_set_t *ds, /* {{{ */
+ value_list_t *vl, notification_meta_t __attribute__((unused)) **meta,
+ void **user_data)
+{
+ fc_writer_t *plugin_list;
+ int status;
+
+ plugin_list = NULL;
+ if (user_data != NULL)
+ plugin_list = *user_data;
+
+ if ((plugin_list == NULL) || (plugin_list[0].plugin == NULL))
+ {
+ static c_complain_t write_complaint = C_COMPLAIN_INIT_STATIC;
+
+ status = plugin_write (/* plugin = */ NULL, ds, vl);
+ if (status == ENOENT)
+ {
+ /* in most cases this is a permanent error, so use the complain
+ * mechanism rather than spamming the logs */
+ c_complain (LOG_INFO, &write_complaint,
+ "Filter subsystem: Built-in target `write': Dispatching value to "
+ "all write plugins failed with status %i (ENOENT). "
+ "Most likely this means you didn't load any write plugins.",
+ status);
+
+ plugin_log_available_writers ();
+ }
+ else if (status != 0)
+ {
+ /* often, this is a permanent error (e.g. target system unavailable),
+ * so use the complain mechanism rather than spamming the logs */
+ c_complain (LOG_INFO, &write_complaint,
+ "Filter subsystem: Built-in target `write': Dispatching value to "
+ "all write plugins failed with status %i.", status);
+ }
+ else
+ {
+ assert (status == 0);
+ c_release (LOG_INFO, &write_complaint, "Filter subsystem: "
+ "Built-in target `write': Some write plugin is back to normal "
+ "operation. `write' succeeded.");
+ }
+ }
+ else
+ {
+ size_t i;
+
+ for (i = 0; plugin_list[i].plugin != NULL; i++)
+ {
+ status = plugin_write (plugin_list[i].plugin, ds, vl);
+ if (status != 0)
+ {
+ c_complain (LOG_INFO, &plugin_list[i].complaint,
+ "Filter subsystem: Built-in target `write': Dispatching value to "
+ "the `%s' plugin failed with status %i.",
+ plugin_list[i].plugin, status);
+
+ plugin_log_available_writers ();
+ }
+ else
+ {
+ c_release (LOG_INFO, &plugin_list[i].complaint,
+ "Filter subsystem: Built-in target `write': Plugin `%s' is back "
+ "to normal operation. `write' succeeded.", plugin_list[i].plugin);
+ }
+ } /* for (i = 0; plugin_list[i] != NULL; i++) */
+ }
+
+ return (FC_TARGET_CONTINUE);
+} /* }}} int fc_bit_write_invoke */
+
+static int fc_init_once (void) /* {{{ */
+{
+ static int done = 0;
+ target_proc_t tproc;
+
+ if (done != 0)
+ return (0);
+
+ memset (&tproc, 0, sizeof (tproc));
+ tproc.create = fc_bit_jump_create;
+ tproc.destroy = fc_bit_jump_destroy;
+ tproc.invoke = fc_bit_jump_invoke;
+ fc_register_target ("jump", tproc);
+
+ memset (&tproc, 0, sizeof (tproc));
+ tproc.create = NULL;
+ tproc.destroy = NULL;
+ tproc.invoke = fc_bit_stop_invoke;
+ fc_register_target ("stop", tproc);
+
+ memset (&tproc, 0, sizeof (tproc));
+ tproc.create = NULL;
+ tproc.destroy = NULL;
+ tproc.invoke = fc_bit_return_invoke;
+ fc_register_target ("return", tproc);
+
+ memset (&tproc, 0, sizeof (tproc));
+ tproc.create = fc_bit_write_create;
+ tproc.destroy = fc_bit_write_destroy;
+ tproc.invoke = fc_bit_write_invoke;
+ fc_register_target ("write", tproc);
+
+ done++;
+ return (0);
+} /* }}} int fc_init_once */
+
+/*
+ * Public functions
+ */
+/* Add a match to list of available matches. */
+int fc_register_match (const char *name, match_proc_t proc) /* {{{ */
+{
+ fc_match_t *m;
+
+ DEBUG ("fc_register_match (%s);", name);
+
+ m = (fc_match_t *) malloc (sizeof (*m));
+ if (m == NULL)
+ return (-ENOMEM);
+ memset (m, 0, sizeof (*m));
+
+ sstrncpy (m->name, name, sizeof (m->name));
+ memcpy (&m->proc, &proc, sizeof (m->proc));
+ m->next = NULL;
+
+ if (match_list_head == NULL)
+ {
+ match_list_head = m;
+ }
+ else
+ {
+ fc_match_t *ptr;
+
+ ptr = match_list_head;
+ while (ptr->next != NULL)
+ ptr = ptr->next;
+
+ ptr->next = m;
+ }
+
+ return (0);
+} /* }}} int fc_register_match */
+
+/* Add a target to list of available targets. */
+int fc_register_target (const char *name, target_proc_t proc) /* {{{ */
+{
+ fc_target_t *t;
+
+ DEBUG ("fc_register_target (%s);", name);
+
+ t = (fc_target_t *) malloc (sizeof (*t));
+ if (t == NULL)
+ return (-ENOMEM);
+ memset (t, 0, sizeof (*t));
+
+ sstrncpy (t->name, name, sizeof (t->name));
+ memcpy (&t->proc, &proc, sizeof (t->proc));
+ t->next = NULL;
+
+ if (target_list_head == NULL)
+ {
+ target_list_head = t;
+ }
+ else
+ {
+ fc_target_t *ptr;
+
+ ptr = target_list_head;
+ while (ptr->next != NULL)
+ ptr = ptr->next;
+
+ ptr->next = t;
+ }
+
+ return (0);
+} /* }}} int fc_register_target */
+
+fc_chain_t *fc_chain_get_by_name (const char *chain_name) /* {{{ */
+{
+ fc_chain_t *chain;
+
+ if (chain_name == NULL)
+ return (NULL);
+
+ for (chain = chain_list_head; chain != NULL; chain = chain->next)
+ if (strcasecmp (chain_name, chain->name) == 0)
+ return (chain);
+
+ return (NULL);
+} /* }}} int fc_chain_get_by_name */
+
+int fc_process_chain (const data_set_t *ds, value_list_t *vl, /* {{{ */
+ fc_chain_t *chain)
+{
+ fc_rule_t *rule;
+ fc_target_t *target;
+ int status;
+
+ if (chain == NULL)
+ return (-1);
+
+ DEBUG ("fc_process_chain (chain = %s);", chain->name);
+
+ status = FC_TARGET_CONTINUE;
+ for (rule = chain->rules; rule != NULL; rule = rule->next)
+ {
+ fc_match_t *match;
+
+ if (rule->name[0] != 0)
+ {
+ DEBUG ("fc_process_chain (%s): Testing the `%s' rule.",
+ chain->name, rule->name);
+ }
+
+ /* N. B.: rule->matches may be NULL. */
+ for (match = rule->matches; match != NULL; match = match->next)
+ {
+ /* FIXME: Pass the meta-data to match targets here (when implemented). */
+ status = (*match->proc.match) (ds, vl, /* meta = */ NULL,
+ &match->user_data);
+ if (status < 0)
+ {
+ WARNING ("fc_process_chain (%s): A match failed.", chain->name);
+ break;
+ }
+ else if (status != FC_MATCH_MATCHES)
+ break;
+ }
+
+ /* for-loop has been aborted: Either error or no match. */
+ if (match != NULL)
+ {
+ status = FC_TARGET_CONTINUE;
+ continue;
+ }
+
+ if (rule->name[0] != 0)
+ {
+ DEBUG ("fc_process_chain (%s): Rule `%s' matches.",
+ chain->name, rule->name);
+ }
+
+ for (target = rule->targets; target != NULL; target = target->next)
+ {
+ /* If we get here, all matches have matched the value. Execute the
+ * target. */
+ /* FIXME: Pass the meta-data to match targets here (when implemented). */
+ status = (*target->proc.invoke) (ds, vl, /* meta = */ NULL,
+ &target->user_data);
+ if (status < 0)
+ {
+ WARNING ("fc_process_chain (%s): A target failed.", chain->name);
+ continue;
+ }
+ else if (status == FC_TARGET_CONTINUE)
+ continue;
+ else if (status == FC_TARGET_STOP)
+ break;
+ else if (status == FC_TARGET_RETURN)
+ break;
+ else
+ {
+ WARNING ("fc_process_chain (%s): Unknown return value "
+ "from target `%s': %i",
+ chain->name, target->name, status);
+ }
+ }
+
+ if ((status == FC_TARGET_STOP)
+ || (status == FC_TARGET_RETURN))
+ {
+ if (rule->name[0] != 0)
+ {
+ DEBUG ("fc_process_chain (%s): Rule `%s' signaled "
+ "the %s condition.",
+ chain->name, rule->name,
+ (status == FC_TARGET_STOP) ? "stop" : "return");
+ }
+ break;
+ }
+ else
+ {
+ status = FC_TARGET_CONTINUE;
+ }
+ } /* for (rule) */
+
+ if (status == FC_TARGET_STOP)
+ return (FC_TARGET_STOP);
+ else if (status == FC_TARGET_RETURN)
+ return (FC_TARGET_CONTINUE);
+
+ /* for-loop has been aborted: A target returned `FC_TARGET_STOP' */
+ if (rule != NULL)
+ return (FC_TARGET_CONTINUE);
+
+ DEBUG ("fc_process_chain (%s): Executing the default targets.",
+ chain->name);
+
+ status = FC_TARGET_CONTINUE;
+ for (target = chain->targets; target != NULL; target = target->next)
+ {
+ /* If we get here, all matches have matched the value. Execute the
+ * target. */
+ /* FIXME: Pass the meta-data to match targets here (when implemented). */
+ status = (*target->proc.invoke) (ds, vl, /* meta = */ NULL,
+ &target->user_data);
+ if (status < 0)
+ {
+ WARNING ("fc_process_chain (%s): The default target failed.",
+ chain->name);
+ }
+ else if (status == FC_TARGET_CONTINUE)
+ continue;
+ else if (status == FC_TARGET_STOP)
+ break;
+ else if (status == FC_TARGET_RETURN)
+ break;
+ else
+ {
+ WARNING ("fc_process_chain (%s): Unknown return value "
+ "from target `%s': %i",
+ chain->name, target->name, status);
+ }
+ }
+
+ if ((status == FC_TARGET_STOP)
+ || (status == FC_TARGET_RETURN))
+ {
+ assert (target != NULL);
+ DEBUG ("fc_process_chain (%s): Default target `%s' signaled "
+ "the %s condition.",
+ chain->name, target->name,
+ (status == FC_TARGET_STOP) ? "stop" : "return");
+ if (status == FC_TARGET_STOP)
+ return (FC_TARGET_STOP);
+ else
+ return (FC_TARGET_CONTINUE);
+ }
+
+ DEBUG ("fc_process_chain (%s): Signaling `continue' at end of chain.",
+ chain->name);
+
+ return (FC_TARGET_CONTINUE);
+} /* }}} int fc_process_chain */
+
+/* Iterate over all rules in the chain and execute all targets for which all
+ * matches match. */
+int fc_default_action (const data_set_t *ds, value_list_t *vl) /* {{{ */
+{
+ /* FIXME: Pass the meta-data to match targets here (when implemented). */
+ return (fc_bit_write_invoke (ds, vl,
+ /* meta = */ NULL, /* user_data = */ NULL));
+} /* }}} int fc_default_action */
+
+int fc_configure (const oconfig_item_t *ci) /* {{{ */
+{
+ fc_init_once ();
+
+ if (ci == NULL)
+ return (-EINVAL);
+
+ if (strcasecmp ("Chain", ci->key) == 0)
+ return (fc_config_add_chain (ci));
+
+ WARNING ("Filter subsystem: Unknown top level config option `%s'.",
+ ci->key);
+
+ return (-1);
+} /* }}} int fc_configure */
+
+/* vim: set sw=2 sts=2 et fdm=marker : */
--- /dev/null
- } /* void rotate_left */
+/**
+ * collectd - src/utils_avltree.c
+ * Copyright (C) 2006,2007 Florian octo Forster
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Authors:
+ * Florian octo Forster <octo at collectd.org>
+ **/
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+
+#include "utils_avltree.h"
+
+#define BALANCE(n) ((((n)->left == NULL) ? 0 : (n)->left->height) \
+ - (((n)->right == NULL) ? 0 : (n)->right->height))
+
+/*
+ * private data types
+ */
+struct c_avl_node_s
+{
+ void *key;
+ void *value;
+
+ int height;
+ struct c_avl_node_s *left;
+ struct c_avl_node_s *right;
+ struct c_avl_node_s *parent;
+};
+typedef struct c_avl_node_s c_avl_node_t;
+
+struct c_avl_tree_s
+{
+ c_avl_node_t *root;
+ int (*compare) (const void *, const void *);
+ int size;
+};
+
+struct c_avl_iterator_s
+{
+ c_avl_tree_t *tree;
+ c_avl_node_t *node;
+};
+
+/*
+ * private functions
+ */
+#if 0
+static void verify_tree (c_avl_node_t *n)
+{
+ if (n == NULL)
+ return;
+
+ verify_tree (n->left);
+ verify_tree (n->right);
+
+ assert ((BALANCE (n) >= -1) && (BALANCE (n) <= 1));
+ assert ((n->parent == NULL) || (n->parent->right == n) || (n->parent->left == n));
+} /* void verify_tree */
+#else
+# define verify_tree(n) /**/
+#endif
+
+static void free_node (c_avl_node_t *n)
+{
+ if (n == NULL)
+ return;
+
+ if (n->left != NULL)
+ free_node (n->left);
+ if (n->right != NULL)
+ free_node (n->right);
+
+ free (n);
+}
+
+static int calc_height (c_avl_node_t *n)
+{
+ int height_left;
+ int height_right;
+
+ if (n == NULL)
+ return (0);
+
+ height_left = (n->left == NULL) ? 0 : n->left->height;
+ height_right = (n->right == NULL) ? 0 : n->right->height;
+
+ return (((height_left > height_right)
+ ? height_left
+ : height_right) + 1);
+} /* int calc_height */
+
+static c_avl_node_t *search (c_avl_tree_t *t, const void *key)
+{
+ c_avl_node_t *n;
+ int cmp;
+
+ n = t->root;
+ while (n != NULL)
+ {
+ cmp = t->compare (key, n->key);
+ if (cmp == 0)
+ return (n);
+ else if (cmp < 0)
+ n = n->left;
+ else
+ n = n->right;
+ }
+
+ return (NULL);
+}
+
+/* (x) (y)
+ * / \ / \
+ * (y) /\ /\ (x)
+ * / \ /_c\ ==> / a\ / \
+ * /\ /\ /____\/\ /\
+ * / a\ /_b\ /_b\ /_c\
+ * /____\
+ */
+static c_avl_node_t *rotate_right (c_avl_tree_t *t, c_avl_node_t *x)
+{
+ c_avl_node_t *p;
+ c_avl_node_t *y;
+ c_avl_node_t *b;
+
++ assert (x != NULL);
++ assert (x->left != NULL);
++
+ p = x->parent;
+ y = x->left;
+ b = y->right;
+
+ x->left = b;
+ if (b != NULL)
+ b->parent = x;
+
+ x->parent = y;
+ y->right = x;
+
+ y->parent = p;
+ assert ((p == NULL) || (p->left == x) || (p->right == x));
+ if (p == NULL)
+ t->root = y;
+ else if (p->left == x)
+ p->left = y;
+ else
+ p->right = y;
+
+ x->height = calc_height (x);
+ y->height = calc_height (y);
+
+ return (y);
++} /* void rotate_right */
+
+/*
+ * (x) (y)
+ * / \ / \
+ * /\ (y) (x) /\
+ * /_a\ / \ ==> / \ / c\
+ * /\ /\ /\ /\/____\
+ * /_b\ / c\ /_a\ /_b\
+ * /____\
+ */
+static c_avl_node_t *rotate_left (c_avl_tree_t *t, c_avl_node_t *x)
+{
+ c_avl_node_t *p;
+ c_avl_node_t *y;
+ c_avl_node_t *b;
+
++ assert (x != NULL);
++ assert (x->right != NULL);
++
+ p = x->parent;
+ y = x->right;
+ b = y->left;
+
+ x->right = b;
+ if (b != NULL)
+ b->parent = x;
+
+ x->parent = y;
+ y->left = x;
+
+ y->parent = p;
+ assert ((p == NULL) || (p->left == x) || (p->right == x));
+ if (p == NULL)
+ t->root = y;
+ else if (p->left == x)
+ p->left = y;
+ else
+ p->right = y;
+
+ x->height = calc_height (x);
+ y->height = calc_height (y);
+
+ return (y);
+} /* void rotate_left */
+
+static c_avl_node_t *rotate_left_right (c_avl_tree_t *t, c_avl_node_t *x)
+{
+ rotate_left (t, x->left);
+ return (rotate_right (t, x));
+} /* void rotate_left_right */
+
+static c_avl_node_t *rotate_right_left (c_avl_tree_t *t, c_avl_node_t *x)
+{
+ rotate_right (t, x->right);
+ return (rotate_left (t, x));
+} /* void rotate_right_left */
+
+static void rebalance (c_avl_tree_t *t, c_avl_node_t *n)
+{
+ int b_top;
+ int b_bottom;
+
+ while (n != NULL)
+ {
+ b_top = BALANCE (n);
+ assert ((b_top >= -2) && (b_top <= 2));
+
+ if (b_top == -2)
+ {
+ assert (n->right != NULL);
+ b_bottom = BALANCE (n->right);
+ assert ((b_bottom >= -1) || (b_bottom <= 1));
+ if (b_bottom == 1)
+ n = rotate_right_left (t, n);
+ else
+ n = rotate_left (t, n);
+ }
+ else if (b_top == 2)
+ {
+ assert (n->left != NULL);
+ b_bottom = BALANCE (n->left);
+ assert ((b_bottom >= -1) || (b_bottom <= 1));
+ if (b_bottom == -1)
+ n = rotate_left_right (t, n);
+ else
+ n = rotate_right (t, n);
+ }
+ else
+ {
+ int height = calc_height (n);
+ if (height == n->height)
+ break;
+ n->height = height;
+ }
+
+ assert (n->height == calc_height (n));
+
+ n = n->parent;
+ } /* while (n != NULL) */
+} /* void rebalance */
+
+static c_avl_node_t *c_avl_node_next (c_avl_node_t *n)
+{
+ c_avl_node_t *r; /* return node */
+
+ if (n == NULL)
+ {
+ return (NULL);
+ }
+
+ /* If we can't descent any further, we have to backtrack to the first
+ * parent that's bigger than we, i. e. who's _left_ child we are. */
+ if (n->right == NULL)
+ {
+ r = n->parent;
+ while ((r != NULL) && (r->parent != NULL))
+ {
+ if (r->left == n)
+ break;
+ n = r;
+ r = n->parent;
+ }
+
+ /* n->right == NULL && r == NULL => t is root and has no next
+ * r->left != n => r->right = n => r->parent == NULL */
+ if ((r == NULL) || (r->left != n))
+ {
+ assert ((r == NULL) || (r->parent == NULL));
+ return (NULL);
+ }
+ else
+ {
+ assert (r->left == n);
+ return (r);
+ }
+ }
+ else
+ {
+ r = n->right;
+ while (r->left != NULL)
+ r = r->left;
+ }
+
+ return (r);
+} /* c_avl_node_t *c_avl_node_next */
+
+static c_avl_node_t *c_avl_node_prev (c_avl_node_t *n)
+{
+ c_avl_node_t *r; /* return node */
+
+ if (n == NULL)
+ {
+ return (NULL);
+ }
+
+ /* If we can't descent any further, we have to backtrack to the first
+ * parent that's smaller than we, i. e. who's _right_ child we are. */
+ if (n->left == NULL)
+ {
+ r = n->parent;
+ while ((r != NULL) && (r->parent != NULL))
+ {
+ if (r->right == n)
+ break;
+ n = r;
+ r = n->parent;
+ }
+
+ /* n->left == NULL && r == NULL => t is root and has no next
+ * r->right != n => r->left = n => r->parent == NULL */
+ if ((r == NULL) || (r->right != n))
+ {
+ assert ((r == NULL) || (r->parent == NULL));
+ return (NULL);
+ }
+ else
+ {
+ assert (r->right == n);
+ return (r);
+ }
+ }
+ else
+ {
+ r = n->left;
+ while (r->right != NULL)
+ r = r->right;
+ }
+
+ return (r);
+} /* c_avl_node_t *c_avl_node_prev */
+
+static int _remove (c_avl_tree_t *t, c_avl_node_t *n)
+{
+ assert ((t != NULL) && (n != NULL));
+
+ if ((n->left != NULL) && (n->right != NULL))
+ {
+ c_avl_node_t *r; /* replacement node */
+ if (BALANCE (n) > 0) /* left subtree is higher */
+ {
+ assert (n->left != NULL);
+ r = c_avl_node_prev (n);
+
+ }
+ else /* right subtree is higher */
+ {
+ assert (n->right != NULL);
+ r = c_avl_node_next (n);
+ }
+
+ assert ((r->left == NULL) || (r->right == NULL));
+
+ /* copy content */
+ n->key = r->key;
+ n->value = r->value;
+
+ n = r;
+ }
+
+ assert ((n->left == NULL) || (n->right == NULL));
+
+ if ((n->left == NULL) && (n->right == NULL))
+ {
+ /* Deleting a leave is easy */
+ if (n->parent == NULL)
+ {
+ assert (t->root == n);
+ t->root = NULL;
+ }
+ else
+ {
+ assert ((n->parent->left == n)
+ || (n->parent->right == n));
+ if (n->parent->left == n)
+ n->parent->left = NULL;
+ else
+ n->parent->right = NULL;
+
+ rebalance (t, n->parent);
+ }
+
+ free_node (n);
+ }
+ else if (n->left == NULL)
+ {
+ assert (BALANCE (n) == -1);
+ assert ((n->parent == NULL) || (n->parent->left == n) || (n->parent->right == n));
+ if (n->parent == NULL)
+ {
+ assert (t->root == n);
+ t->root = n->right;
+ }
+ else if (n->parent->left == n)
+ {
+ n->parent->left = n->right;
+ }
+ else
+ {
+ n->parent->right = n->right;
+ }
+ n->right->parent = n->parent;
+
+ if (n->parent != NULL)
+ rebalance (t, n->parent);
+
+ n->right = NULL;
+ free_node (n);
+ }
+ else if (n->right == NULL)
+ {
+ assert (BALANCE (n) == 1);
+ assert ((n->parent == NULL) || (n->parent->left == n) || (n->parent->right == n));
+ if (n->parent == NULL)
+ {
+ assert (t->root == n);
+ t->root = n->left;
+ }
+ else if (n->parent->left == n)
+ {
+ n->parent->left = n->left;
+ }
+ else
+ {
+ n->parent->right = n->left;
+ }
+ n->left->parent = n->parent;
+
+ if (n->parent != NULL)
+ rebalance (t, n->parent);
+
+ n->left = NULL;
+ free_node (n);
+ }
+ else
+ {
+ assert (0);
+ }
+
+ return (0);
+} /* void *_remove */
+
+/*
+ * public functions
+ */
+c_avl_tree_t *c_avl_create (int (*compare) (const void *, const void *))
+{
+ c_avl_tree_t *t;
+
+ if (compare == NULL)
+ return (NULL);
+
+ if ((t = (c_avl_tree_t *) malloc (sizeof (c_avl_tree_t))) == NULL)
+ return (NULL);
+
+ t->root = NULL;
+ t->compare = compare;
+ t->size = 0;
+
+ return (t);
+}
+
+void c_avl_destroy (c_avl_tree_t *t)
+{
+ if (t == NULL)
+ return;
+ free_node (t->root);
+ free (t);
+}
+
+int c_avl_insert (c_avl_tree_t *t, void *key, void *value)
+{
+ c_avl_node_t *new;
+ c_avl_node_t *nptr;
+ int cmp;
+
+ if ((new = (c_avl_node_t *) malloc (sizeof (c_avl_node_t))) == NULL)
+ return (-1);
+
+ new->key = key;
+ new->value = value;
+ new->height = 1;
+ new->left = NULL;
+ new->right = NULL;
+
+ if (t->root == NULL)
+ {
+ new->parent = NULL;
+ t->root = new;
+ t->size = 1;
+ return (0);
+ }
+
+ nptr = t->root;
+ while (42)
+ {
+ cmp = t->compare (nptr->key, new->key);
+ if (cmp == 0)
+ {
+ free_node (new);
+ return (1);
+ }
+ else if (cmp < 0)
+ {
+ /* nptr < new */
+ if (nptr->right == NULL)
+ {
+ nptr->right = new;
+ new->parent = nptr;
+ rebalance (t, nptr);
+ break;
+ }
+ else
+ {
+ nptr = nptr->right;
+ }
+ }
+ else /* if (cmp > 0) */
+ {
+ /* nptr > new */
+ if (nptr->left == NULL)
+ {
+ nptr->left = new;
+ new->parent = nptr;
+ rebalance (t, nptr);
+ break;
+ }
+ else
+ {
+ nptr = nptr->left;
+ }
+ }
+ } /* while (42) */
+
+ verify_tree (t->root);
+ ++t->size;
+ return (0);
+} /* int c_avl_insert */
+
+int c_avl_remove (c_avl_tree_t *t, const void *key, void **rkey, void **rvalue)
+{
+ c_avl_node_t *n;
+ int status;
+
+ assert (t != NULL);
+
+ n = search (t, key);
+ if (n == NULL)
+ return (-1);
+
+ if (rkey != NULL)
+ *rkey = n->key;
+ if (rvalue != NULL)
+ *rvalue = n->value;
+
+ status = _remove (t, n);
+ verify_tree (t->root);
+ --t->size;
+ return (status);
+} /* void *c_avl_remove */
+
+int c_avl_get (c_avl_tree_t *t, const void *key, void **value)
+{
+ c_avl_node_t *n;
+
+ assert (t != NULL);
+
+ n = search (t, key);
+ if (n == NULL)
+ return (-1);
+
+ if (value != NULL)
+ *value = n->value;
+
+ return (0);
+}
+
+int c_avl_pick (c_avl_tree_t *t, void **key, void **value)
+{
+ c_avl_node_t *n;
+ c_avl_node_t *p;
+
+ if ((key == NULL) || (value == NULL))
+ return (-1);
+ if (t->root == NULL)
+ return (-1);
+
+ n = t->root;
+ while ((n->left != NULL) || (n->right != NULL))
+ {
+ if (n->left == NULL)
+ {
+ n = n->right;
+ continue;
+ }
+ else if (n->right == NULL)
+ {
+ n = n->left;
+ continue;
+ }
+
+ if (n->left->height > n->right->height)
+ n = n->left;
+ else
+ n = n->right;
+ }
+
+ p = n->parent;
+ if (p == NULL)
+ t->root = NULL;
+ else if (p->left == n)
+ p->left = NULL;
+ else
+ p->right = NULL;
+
+ *key = n->key;
+ *value = n->value;
+
+ free_node (n);
+ rebalance (t, p);
+
+ return (0);
+} /* int c_avl_pick */
+
+c_avl_iterator_t *c_avl_get_iterator (c_avl_tree_t *t)
+{
+ c_avl_iterator_t *iter;
+
+ if (t == NULL)
+ return (NULL);
+
+ iter = (c_avl_iterator_t *) malloc (sizeof (c_avl_iterator_t));
+ if (iter == NULL)
+ return (NULL);
+ memset (iter, '\0', sizeof (c_avl_iterator_t));
+ iter->tree = t;
+
+ return (iter);
+} /* c_avl_iterator_t *c_avl_get_iterator */
+
+int c_avl_iterator_next (c_avl_iterator_t *iter, void **key, void **value)
+{
+ c_avl_node_t *n;
+
+ if ((iter == NULL) || (key == NULL) || (value == NULL))
+ return (-1);
+
+ if (iter->node == NULL)
+ {
+ for (n = iter->tree->root; n != NULL; n = n->left)
+ if (n->left == NULL)
+ break;
+ iter->node = n;
+ }
+ else
+ {
+ n = c_avl_node_next (iter->node);
+ }
+
+ if (n == NULL)
+ return (-1);
+
+ iter->node = n;
+ *key = n->key;
+ *value = n->value;
+
+ return (0);
+} /* int c_avl_iterator_next */
+
+int c_avl_iterator_prev (c_avl_iterator_t *iter, void **key, void **value)
+{
+ c_avl_node_t *n;
+
+ if ((iter == NULL) || (key == NULL) || (value == NULL))
+ return (-1);
+
+ if (iter->node == NULL)
+ {
+ for (n = iter->tree->root; n != NULL; n = n->left)
+ if (n->right == NULL)
+ break;
+ iter->node = n;
+ }
+ else
+ {
+ n = c_avl_node_prev (iter->node);
+ }
+
+ if (n == NULL)
+ return (-1);
+
+ iter->node = n;
+ *key = n->key;
+ *value = n->value;
+
+ return (0);
+} /* int c_avl_iterator_prev */
+
+void c_avl_iterator_destroy (c_avl_iterator_t *iter)
+{
+ free (iter);
+}
+
+int c_avl_size (c_avl_tree_t *t)
+{
+ if (t == NULL)
+ return (0);
+ return (t->size);
+}