1 /**
2 * collectd - src/target_replace.c
3 * Copyright (C) 2008 Florian Forster
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 * Florian Forster <octo at collectd.org>
25 **/
27 #include "collectd.h"
29 #include "common.h"
30 #include "filter_chain.h"
31 #include "utils_subst.h"
33 #include <regex.h>
35 struct tr_action_s;
36 typedef struct tr_action_s tr_action_t;
37 struct tr_action_s
38 {
39 regex_t re;
40 char *replacement;
41 int may_be_empty;
43 tr_action_t *next;
44 };
46 struct tr_data_s
47 {
48 tr_action_t *host;
49 tr_action_t *plugin;
50 tr_action_t *plugin_instance;
51 /* tr_action_t *type; */
52 tr_action_t *type_instance;
53 };
54 typedef struct tr_data_s tr_data_t;
56 static char *tr_strdup (const char *orig) /* {{{ */
57 {
58 size_t sz;
59 char *dest;
61 if (orig == NULL)
62 return (NULL);
64 sz = strlen (orig) + 1;
65 dest = malloc (sz);
66 if (dest == NULL)
67 return (NULL);
69 memcpy (dest, orig, sz);
71 return (dest);
72 } /* }}} char *tr_strdup */
74 static void tr_action_destroy (tr_action_t *act) /* {{{ */
75 {
76 if (act == NULL)
77 return;
79 regfree (&act->re);
80 sfree (act->replacement);
82 if (act->next != NULL)
83 tr_action_destroy (act->next);
85 sfree (act);
86 } /* }}} void tr_action_destroy */
88 static int tr_config_add_action (tr_action_t **dest, /* {{{ */
89 const oconfig_item_t *ci, int may_be_empty)
90 {
91 tr_action_t *act;
92 int status;
94 if (dest == NULL)
95 return (-EINVAL);
97 if ((ci->values_num != 2)
98 || (ci->values[0].type != OCONFIG_TYPE_STRING)
99 || (ci->values[1].type != OCONFIG_TYPE_STRING))
100 {
101 ERROR ("Target `replace': The `%s' option requires exactly two string "
102 "arguments.", ci->key);
103 return (-1);
104 }
106 act = calloc (1, sizeof (*act));
107 if (act == NULL)
108 {
109 ERROR ("tr_config_add_action: calloc failed.");
110 return (-ENOMEM);
111 }
113 act->replacement = NULL;
114 act->may_be_empty = may_be_empty;
116 status = regcomp (&act->re, ci->values[0].value.string, REG_EXTENDED);
117 if (status != 0)
118 {
119 char errbuf[1024] = "";
121 /* regerror assures null termination. */
122 regerror (status, &act->re, errbuf, sizeof (errbuf));
123 ERROR ("Target `replace': Compiling the regular expression `%s' "
124 "failed: %s.",
125 ci->values[0].value.string, errbuf);
126 sfree (act);
127 return (-EINVAL);
128 }
130 act->replacement = tr_strdup (ci->values[1].value.string);
131 if (act->replacement == NULL)
132 {
133 ERROR ("tr_config_add_action: tr_strdup failed.");
134 regfree (&act->re);
135 sfree (act);
136 return (-ENOMEM);
137 }
139 /* Insert action at end of list. */
140 if (*dest == NULL)
141 *dest = act;
142 else
143 {
144 tr_action_t *prev;
146 prev = *dest;
147 while (prev->next != NULL)
148 prev = prev->next;
150 prev->next = act;
151 }
153 return (0);
154 } /* }}} int tr_config_add_action */
156 static int tr_action_invoke (tr_action_t *act_head, /* {{{ */
157 char *buffer_in, size_t buffer_in_size, int may_be_empty)
158 {
159 int status;
160 char buffer[DATA_MAX_NAME_LEN];
161 regmatch_t matches[8] = { [0] = { 0 } };
163 if (act_head == NULL)
164 return (-EINVAL);
166 sstrncpy (buffer, buffer_in, sizeof (buffer));
168 DEBUG ("target_replace plugin: tr_action_invoke: <- buffer = %s;", buffer);
170 for (tr_action_t *act = act_head; act != NULL; act = act->next)
171 {
172 char temp[DATA_MAX_NAME_LEN];
173 char *subst_status;
175 status = regexec (&act->re, buffer,
176 STATIC_ARRAY_SIZE (matches), matches,
177 /* flags = */ 0);
178 if (status == REG_NOMATCH)
179 continue;
180 else if (status != 0)
181 {
182 char errbuf[1024] = "";
184 regerror (status, &act->re, errbuf, sizeof (errbuf));
185 ERROR ("Target `replace': Executing a regular expression failed: %s.",
186 errbuf);
187 continue;
188 }
190 subst_status = subst (temp, sizeof (temp), buffer,
191 (size_t) matches[0].rm_so, (size_t) matches[0].rm_eo, act->replacement);
192 if (subst_status == NULL)
193 {
194 ERROR ("Target `replace': subst (buffer = %s, start = %zu, end = %zu, "
195 "replacement = %s) failed.",
196 buffer, (size_t) matches[0].rm_so, (size_t) matches[0].rm_eo,
197 act->replacement);
198 continue;
199 }
200 sstrncpy (buffer, temp, sizeof (buffer));
202 DEBUG ("target_replace plugin: tr_action_invoke: -- buffer = %s;", buffer);
203 } /* for (act = act_head; act != NULL; act = act->next) */
205 if ((may_be_empty == 0) && (buffer[0] == 0))
206 {
207 WARNING ("Target `replace': Replacement resulted in an empty string, "
208 "which is not allowed for this buffer (`host' or `plugin').");
209 return (0);
210 }
212 DEBUG ("target_replace plugin: tr_action_invoke: -> buffer = %s;", buffer);
213 sstrncpy (buffer_in, buffer, buffer_in_size);
215 return (0);
216 } /* }}} int tr_action_invoke */
218 static int tr_destroy (void **user_data) /* {{{ */
219 {
220 tr_data_t *data;
222 if (user_data == NULL)
223 return (-EINVAL);
225 data = *user_data;
226 if (data == NULL)
227 return (0);
229 tr_action_destroy (data->host);
230 tr_action_destroy (data->plugin);
231 tr_action_destroy (data->plugin_instance);
232 /* tr_action_destroy (data->type); */
233 tr_action_destroy (data->type_instance);
234 sfree (data);
236 return (0);
237 } /* }}} int tr_destroy */
239 static int tr_create (const oconfig_item_t *ci, void **user_data) /* {{{ */
240 {
241 tr_data_t *data;
242 int status;
244 data = calloc (1, sizeof (*data));
245 if (data == NULL)
246 {
247 ERROR ("tr_create: calloc failed.");
248 return (-ENOMEM);
249 }
251 data->host = NULL;
252 data->plugin = NULL;
253 data->plugin_instance = NULL;
254 /* data->type = NULL; */
255 data->type_instance = NULL;
257 status = 0;
258 for (int i = 0; i < ci->children_num; i++)
259 {
260 oconfig_item_t *child = ci->children + i;
262 if ((strcasecmp ("Host", child->key) == 0)
263 || (strcasecmp ("Hostname", child->key) == 0))
264 status = tr_config_add_action (&data->host, child,
265 /* may be empty = */ 0);
266 else if (strcasecmp ("Plugin", child->key) == 0)
267 status = tr_config_add_action (&data->plugin, child,
268 /* may be empty = */ 0);
269 else if (strcasecmp ("PluginInstance", child->key) == 0)
270 status = tr_config_add_action (&data->plugin_instance, child,
271 /* may be empty = */ 1);
272 #if 0
273 else if (strcasecmp ("Type", child->key) == 0)
274 status = tr_config_add_action (&data->type, child,
275 /* may be empty = */ 0);
276 #endif
277 else if (strcasecmp ("TypeInstance", child->key) == 0)
278 status = tr_config_add_action (&data->type_instance, child,
279 /* may be empty = */ 1);
280 else
281 {
282 ERROR ("Target `replace': The `%s' configuration option is not understood "
283 "and will be ignored.", child->key);
284 status = 0;
285 }
287 if (status != 0)
288 break;
289 }
291 /* Additional sanity-checking */
292 while (status == 0)
293 {
294 if ((data->host == NULL)
295 && (data->plugin == NULL)
296 && (data->plugin_instance == NULL)
297 /* && (data->type == NULL) */
298 && (data->type_instance == NULL))
299 {
300 ERROR ("Target `replace': You need to set at least one of `Host', "
301 "`Plugin', `PluginInstance' or `TypeInstance'.");
302 status = -1;
303 }
305 break;
306 }
308 if (status != 0)
309 {
310 tr_destroy ((void *) &data);
311 return (status);
312 }
314 *user_data = data;
315 return (0);
316 } /* }}} int tr_create */
318 static int tr_invoke (const data_set_t *ds, value_list_t *vl, /* {{{ */
319 notification_meta_t __attribute__((unused)) **meta, void **user_data)
320 {
321 tr_data_t *data;
323 if ((ds == NULL) || (vl == NULL) || (user_data == NULL))
324 return (-EINVAL);
326 data = *user_data;
327 if (data == NULL)
328 {
329 ERROR ("Target `replace': Invoke: `data' is NULL.");
330 return (-EINVAL);
331 }
333 #define HANDLE_FIELD(f,e) \
334 if (data->f != NULL) \
335 tr_action_invoke (data->f, vl->f, sizeof (vl->f), e)
336 HANDLE_FIELD (host, 0);
337 HANDLE_FIELD (plugin, 0);
338 HANDLE_FIELD (plugin_instance, 1);
339 /* HANDLE_FIELD (type); */
340 HANDLE_FIELD (type_instance, 1);
342 return (FC_TARGET_CONTINUE);
343 } /* }}} int tr_invoke */
345 void module_register (void)
346 {
347 target_proc_t tproc = { 0 };
349 tproc.create = tr_create;
350 tproc.destroy = tr_destroy;
351 tproc.invoke = tr_invoke;
352 fc_register_target ("replace", tproc);
353 } /* module_register */
355 /* vim: set sw=2 sts=2 tw=78 et fdm=marker : */