1 /**
2  * collectd - src/utils_threshold.c
3  * Copyright (C) 2014       Pierre-Yves Ritschard
4  *
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:
11  *
12  * The above copyright notice and this permission notice shall be included in
13  * all copies or substantial portions of the Software.
14  *
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.
22  *
23  * Authors:
24  *   Pierre-Yves Ritschard <pyr at spootnik.org>
25  **/
26 
27 #include "collectd.h"
28 
29 #include "utils/avltree/avltree.h"
30 #include "utils/common/common.h"
31 #include "utils_threshold.h"
32 
33 #include <pthread.h>
34 
35 /*
36  * Exported symbols
37  * {{{ */
38 c_avl_tree_t *threshold_tree = NULL;
39 pthread_mutex_t threshold_lock = PTHREAD_MUTEX_INITIALIZER;
40 /* }}} */
41 
42 /*
43  * threshold_t *threshold_get
44  *
45  * Retrieve one specific threshold configuration. For looking up a threshold
46  * matching a value_list_t, see "threshold_search" below. Returns NULL if the
47  * specified threshold doesn't exist.
48  */
threshold_get(const char * hostname,const char * plugin,const char * plugin_instance,const char * type,const char * type_instance)49 threshold_t *threshold_get(const char *hostname, const char *plugin,
50                            const char *plugin_instance, const char *type,
51                            const char *type_instance) { /* {{{ */
52   char name[6 * DATA_MAX_NAME_LEN];
53   threshold_t *th = NULL;
54 
55   format_name(name, sizeof(name), (hostname == NULL) ? "" : hostname,
56               (plugin == NULL) ? "" : plugin, plugin_instance,
57               (type == NULL) ? "" : type, type_instance);
58   name[sizeof(name) - 1] = '\0';
59 
60   if (c_avl_get(threshold_tree, name, (void *)&th) == 0)
61     return th;
62   else
63     return NULL;
64 } /* }}} threshold_t *threshold_get */
65 
66 /*
67  * threshold_t *threshold_search
68  *
69  * Searches for a threshold configuration using all the possible variations of
70  * "Host", "Plugin" and "Type" blocks. Returns NULL if no threshold could be
71  * found.
72  * XXX: This is likely the least efficient function in collectd.
73  */
threshold_search(const value_list_t * vl)74 threshold_t *threshold_search(const value_list_t *vl) { /* {{{ */
75   threshold_t *th;
76 
77   if ((th = threshold_get(vl->host, vl->plugin, vl->plugin_instance, vl->type,
78                           vl->type_instance)) != NULL)
79     return th;
80   else if ((th = threshold_get(vl->host, vl->plugin, vl->plugin_instance,
81                                vl->type, NULL)) != NULL)
82     return th;
83   else if ((th = threshold_get(vl->host, vl->plugin, NULL, vl->type,
84                                vl->type_instance)) != NULL)
85     return th;
86   else if ((th = threshold_get(vl->host, vl->plugin, NULL, vl->type, NULL)) !=
87            NULL)
88     return th;
89   else if ((th = threshold_get(vl->host, "", NULL, vl->type,
90                                vl->type_instance)) != NULL)
91     return th;
92   else if ((th = threshold_get(vl->host, "", NULL, vl->type, NULL)) != NULL)
93     return th;
94   else if ((th = threshold_get("", vl->plugin, vl->plugin_instance, vl->type,
95                                vl->type_instance)) != NULL)
96     return th;
97   else if ((th = threshold_get("", vl->plugin, vl->plugin_instance, vl->type,
98                                NULL)) != NULL)
99     return th;
100   else if ((th = threshold_get("", vl->plugin, NULL, vl->type,
101                                vl->type_instance)) != NULL)
102     return th;
103   else if ((th = threshold_get("", vl->plugin, NULL, vl->type, NULL)) != NULL)
104     return th;
105   else if ((th = threshold_get("", "", NULL, vl->type, vl->type_instance)) !=
106            NULL)
107     return th;
108   else if ((th = threshold_get("", "", NULL, vl->type, NULL)) != NULL)
109     return th;
110 
111   return NULL;
112 } /* }}} threshold_t *threshold_search */
113 
ut_search_threshold(const value_list_t * vl,threshold_t * ret_threshold)114 int ut_search_threshold(const value_list_t *vl, /* {{{ */
115                         threshold_t *ret_threshold) {
116   threshold_t *t;
117 
118   if (vl == NULL)
119     return EINVAL;
120 
121   /* Is this lock really necessary? */
122   pthread_mutex_lock(&threshold_lock);
123   t = threshold_search(vl);
124   if (t == NULL) {
125     pthread_mutex_unlock(&threshold_lock);
126     return ENOENT;
127   }
128 
129   memcpy(ret_threshold, t, sizeof(*ret_threshold));
130   pthread_mutex_unlock(&threshold_lock);
131 
132   ret_threshold->next = NULL;
133 
134   return 0;
135 } /* }}} int ut_search_threshold */
136