1 /**
2 * collectd - src/target_replace.c
3 * Copyright (C) 2008 Florian Forster
4 *
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.
8 *
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.
13 *
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
17 *
18 * Authors:
19 * Florian Forster <octo at verplant.org>
20 **/
22 /*
23 * First tell the compiler to stick to the C99 and POSIX standards as close as
24 * possible.
25 */
26 #ifndef __STRICT_ANSI__ /* {{{ */
27 # define __STRICT_ANSI__
28 #endif
30 #ifndef _ISOC99_SOURCE
31 # define _ISOC99_SOURCE
32 #endif
34 #ifdef _POSIX_C_SOURCE
35 # undef _POSIX_C_SOURCE
36 #endif
37 #define _POSIX_C_SOURCE 200112L
39 #ifdef _XOPEN_SOURCE
40 # undef _XOPEN_SOURCE
41 #endif
42 #define _XOPEN_SOURCE 600
44 #ifndef _REENTRANT
45 # define _REENTRANT
46 #endif
48 #ifndef _THREAD_SAFE
49 # define _THREAD_SAFE
50 #endif
52 #ifdef _GNU_SOURCE
53 # undef _GNU_SOURCE
54 #endif
55 /* }}} */
57 #include "collectd.h"
58 #include "common.h"
59 #include "filter_chain.h"
60 #include "utils_subst.h"
62 #include <regex.h>
64 struct tr_action_s;
65 typedef struct tr_action_s tr_action_t;
66 struct tr_action_s
67 {
68 regex_t re;
69 char *replacement;
70 int may_be_empty;
72 tr_action_t *next;
73 };
75 struct tr_data_s
76 {
77 tr_action_t *host;
78 tr_action_t *plugin;
79 tr_action_t *plugin_instance;
80 /* tr_action_t *type; */
81 tr_action_t *type_instance;
82 };
83 typedef struct tr_data_s tr_data_t;
85 static char *tr_strdup (const char *orig) /* {{{ */
86 {
87 size_t sz;
88 char *dest;
90 if (orig == NULL)
91 return (NULL);
93 sz = strlen (orig) + 1;
94 dest = (char *) malloc (sz);
95 if (dest == NULL)
96 return (NULL);
98 memcpy (dest, orig, sz);
100 return (dest);
101 } /* }}} char *tr_strdup */
103 static void tr_action_destroy (tr_action_t *act) /* {{{ */
104 {
105 if (act == NULL)
106 return;
108 regfree (&act->re);
109 sfree (act->replacement);
111 if (act->next != NULL)
112 tr_action_destroy (act->next);
114 sfree (act);
115 } /* }}} void tr_action_destroy */
117 static int tr_config_add_action (tr_action_t **dest, /* {{{ */
118 const oconfig_item_t *ci, int may_be_empty)
119 {
120 tr_action_t *act;
121 int status;
123 if (dest == NULL)
124 return (-EINVAL);
126 if ((ci->values_num != 2)
127 || (ci->values[0].type != OCONFIG_TYPE_STRING)
128 || (ci->values[1].type != OCONFIG_TYPE_STRING))
129 {
130 ERROR ("Target `replace': The `%s' option requires exactly two string "
131 "arguments.", ci->key);
132 return (-1);
133 }
135 act = (tr_action_t *) malloc (sizeof (*act));
136 if (act == NULL)
137 {
138 ERROR ("tr_config_add_action: malloc failed.");
139 return (-ENOMEM);
140 }
141 memset (act, 0, sizeof (*act));
143 act->replacement = NULL;
144 act->may_be_empty = may_be_empty;
146 status = regcomp (&act->re, ci->values[0].value.string, REG_EXTENDED);
147 if (status != 0)
148 {
149 char errbuf[1024] = "";
151 /* regerror assures null termination. */
152 regerror (status, &act->re, errbuf, sizeof (errbuf));
153 ERROR ("Target `replace': Compiling the regular expression `%s' "
154 "failed: %s.",
155 ci->values[0].value.string, errbuf);
156 sfree (act);
157 return (-EINVAL);
158 }
160 act->replacement = tr_strdup (ci->values[1].value.string);
161 if (act->replacement == NULL)
162 {
163 ERROR ("tr_config_add_action: tr_strdup failed.");
164 regfree (&act->re);
165 sfree (act);
166 return (-ENOMEM);
167 }
169 /* Insert action at end of list. */
170 if (*dest == NULL)
171 *dest = act;
172 else
173 {
174 tr_action_t *prev;
176 prev = *dest;
177 while (prev->next != NULL)
178 prev = prev->next;
180 prev->next = act;
181 }
183 return (0);
184 } /* }}} int tr_config_add_action */
186 static int tr_action_invoke (tr_action_t *act_head, /* {{{ */
187 char *buffer_in, size_t buffer_in_size, int may_be_empty)
188 {
189 tr_action_t *act;
190 int status;
191 char buffer[DATA_MAX_NAME_LEN];
192 regmatch_t matches[8];
194 if (act_head == NULL)
195 return (-EINVAL);
197 sstrncpy (buffer, buffer_in, sizeof (buffer));
198 memset (matches, 0, sizeof (matches));
200 DEBUG ("target_replace plugin: tr_action_invoke: <- buffer = %s;", buffer);
202 for (act = act_head; act != NULL; act = act->next)
203 {
204 char temp[DATA_MAX_NAME_LEN];
205 char *subst_status;
207 status = regexec (&act->re, buffer,
208 STATIC_ARRAY_SIZE (matches), matches,
209 /* flags = */ 0);
210 if (status == REG_NOMATCH)
211 continue;
212 else if (status != 0)
213 {
214 char errbuf[1024] = "";
216 regerror (status, &act->re, errbuf, sizeof (errbuf));
217 ERROR ("Target `replace': Executing a regular expression failed: %s.",
218 errbuf);
219 continue;
220 }
222 subst_status = subst (temp, sizeof (temp), buffer,
223 matches[0].rm_so, matches[0].rm_eo, act->replacement);
224 if (subst_status == NULL)
225 {
226 ERROR ("Target `replace': subst (buffer = %s, start = %zu, end = %zu, "
227 "replacement = %s) failed.",
228 buffer, (size_t) matches[0].rm_so, (size_t) matches[0].rm_eo,
229 act->replacement);
230 continue;
231 }
232 sstrncpy (buffer, temp, sizeof (buffer));
234 DEBUG ("target_replace plugin: tr_action_invoke: -- buffer = %s;", buffer);
235 } /* for (act = act_head; act != NULL; act = act->next) */
237 if ((may_be_empty == 0) && (buffer[0] == 0))
238 {
239 WARNING ("Target `replace': Replacement resulted in an empty string, "
240 "which is not allowed for this buffer (`host' or `plugin').");
241 return (0);
242 }
244 DEBUG ("target_replace plugin: tr_action_invoke: -> buffer = %s;", buffer);
245 sstrncpy (buffer_in, buffer, buffer_in_size);
247 return (0);
248 } /* }}} int tr_action_invoke */
250 static int tr_destroy (void **user_data) /* {{{ */
251 {
252 tr_data_t *data;
254 if (user_data == NULL)
255 return (-EINVAL);
257 data = *user_data;
258 if (data == NULL)
259 return (0);
261 tr_action_destroy (data->host);
262 tr_action_destroy (data->plugin);
263 tr_action_destroy (data->plugin_instance);
264 /* tr_action_destroy (data->type); */
265 tr_action_destroy (data->type_instance);
266 sfree (data);
268 return (0);
269 } /* }}} int tr_destroy */
271 static int tr_create (const oconfig_item_t *ci, void **user_data) /* {{{ */
272 {
273 tr_data_t *data;
274 int status;
275 int i;
277 data = (tr_data_t *) malloc (sizeof (*data));
278 if (data == NULL)
279 {
280 ERROR ("tr_create: malloc failed.");
281 return (-ENOMEM);
282 }
283 memset (data, 0, sizeof (*data));
285 data->host = NULL;
286 data->plugin = NULL;
287 data->plugin_instance = NULL;
288 /* data->type = NULL; */
289 data->type_instance = NULL;
291 status = 0;
292 for (i = 0; i < ci->children_num; i++)
293 {
294 oconfig_item_t *child = ci->children + i;
296 if ((strcasecmp ("Host", child->key) == 0)
297 || (strcasecmp ("Hostname", child->key) == 0))
298 status = tr_config_add_action (&data->host, child,
299 /* may be empty = */ 0);
300 else if (strcasecmp ("Plugin", child->key) == 0)
301 status = tr_config_add_action (&data->plugin, child,
302 /* may be empty = */ 0);
303 else if (strcasecmp ("PluginInstance", child->key) == 0)
304 status = tr_config_add_action (&data->plugin_instance, child,
305 /* may be empty = */ 1);
306 #if 0
307 else if (strcasecmp ("Type", child->key) == 0)
308 status = tr_config_add_action (&data->type, child,
309 /* may be empty = */ 0);
310 #endif
311 else if (strcasecmp ("TypeInstance", child->key) == 0)
312 status = tr_config_add_action (&data->type_instance, child,
313 /* may be empty = */ 1);
314 else
315 {
316 ERROR ("Target `replace': The `%s' configuration option is not understood "
317 "and will be ignored.", child->key);
318 status = 0;
319 }
321 if (status != 0)
322 break;
323 }
325 /* Additional sanity-checking */
326 while (status == 0)
327 {
328 if ((data->host == NULL)
329 && (data->plugin == NULL)
330 && (data->plugin_instance == NULL)
331 /* && (data->type == NULL) */
332 && (data->type_instance == NULL))
333 {
334 ERROR ("Target `replace': You need to set at lease one of `Host', "
335 "`Plugin', `PluginInstance', `Type', or `TypeInstance'.");
336 status = -1;
337 }
339 break;
340 }
342 if (status != 0)
343 {
344 tr_destroy ((void *) &data);
345 return (status);
346 }
348 *user_data = data;
349 return (0);
350 } /* }}} int tr_create */
352 static int tr_invoke (const data_set_t *ds, value_list_t *vl, /* {{{ */
353 notification_meta_t __attribute__((unused)) **meta, void **user_data)
354 {
355 tr_data_t *data;
357 if ((ds == NULL) || (vl == NULL) || (user_data == NULL))
358 return (-EINVAL);
360 data = *user_data;
361 if (data == NULL)
362 {
363 ERROR ("Target `replace': Invoke: `data' is NULL.");
364 return (-EINVAL);
365 }
367 #define HANDLE_FIELD(f,e) \
368 if (data->f != NULL) \
369 tr_action_invoke (data->f, vl->f, sizeof (vl->f), e)
370 HANDLE_FIELD (host, 0);
371 HANDLE_FIELD (plugin, 0);
372 HANDLE_FIELD (plugin_instance, 1);
373 /* HANDLE_FIELD (type); */
374 HANDLE_FIELD (type_instance, 1);
376 return (FC_TARGET_CONTINUE);
377 } /* }}} int tr_invoke */
379 void module_register (void)
380 {
381 target_proc_t tproc;
383 memset (&tproc, 0, sizeof (tproc));
384 tproc.create = tr_create;
385 tproc.destroy = tr_destroy;
386 tproc.invoke = tr_invoke;
387 fc_register_target ("replace", tproc);
388 } /* module_register */
390 /* vim: set sw=2 sts=2 tw=78 et fdm=marker : */