1 /**
2 * collectd - src/configfile.c
3 * Copyright (C) 2005 Florian octo 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; either version 2 of the License, or (at your
8 * option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 *
19 * Authors:
20 * Florian octo Forster <octo at verplant.org>
21 **/
23 /*
24 * FIXME:
25 * - remove all (I mean *ALL*) calls to `fprintf': `stderr' will have been
26 * closed.
27 */
29 #include "collectd.h"
31 #include "libconfig/libconfig.h"
33 #include "plugin.h"
34 #include "configfile.h"
35 #include "utils_debug.h"
37 #define SHORTOPT_NONE 0
39 #define ERR_NOT_NESTED "Sections cannot be nested.\n"
40 #define ERR_SECTION_ONLY "`%s' can only be used as section.\n"
41 #define ERR_NEEDS_ARG "Section `%s' needs an argument.\n"
42 #define ERR_NEEDS_SECTION "`%s' can only be used within a section.\n"
44 #ifdef HAVE_LIBRRD
45 extern int operating_mode;
46 #else
47 static int operating_mode = MODE_LOCAL;
48 #endif
50 typedef struct cf_callback
51 {
52 char *type;
53 int (*callback) (char *, char *);
54 char **keys;
55 int keys_num;
56 struct cf_callback *next;
57 } cf_callback_t;
59 static cf_callback_t *first_callback = NULL;
61 static int nesting_depth = 0;
62 static char *current_module = NULL;
64 /* cf_register needs this prototype */
65 int cf_callback_general (const char *, const char *, const char *,
66 const char *, lc_flags_t, void *);
68 /*
69 * Functions to handle register/unregister, search, ...
70 */
71 cf_callback_t *cf_search (char *type)
72 {
73 cf_callback_t *cf_cb;
75 if (type == NULL)
76 return (NULL);
78 for (cf_cb = first_callback; cf_cb != NULL; cf_cb = cf_cb->next)
79 if (strcasecmp (cf_cb->type, type) == 0)
80 break;
82 return (cf_cb);
83 }
85 int cf_dispatch (char *type, const char *orig_key, const char *orig_value)
86 {
87 cf_callback_t *cf_cb;
88 char *key;
89 char *value;
90 int ret;
91 int i;
93 if ((cf_cb = cf_search (type)) == NULL)
94 {
95 fprintf (stderr, "Plugin `%s' did not register a callback.\n", type);
96 return (-1);
97 }
99 if ((key = strdup (orig_key)) == NULL)
100 return (1);
101 if ((value = strdup (orig_value)) == NULL)
102 {
103 free (key);
104 return (2);
105 }
107 ret = -1;
109 for (i = 0; i < cf_cb->keys_num; i++)
110 {
111 if (strcasecmp (cf_cb->keys[i], key) == 0)
112 {
113 ret = (*cf_cb->callback) (key, value);
114 break;
115 }
116 }
118 if (i >= cf_cb->keys_num)
119 fprintf (stderr, "Plugin `%s' did not register for value `%s'.\n", type, key);
121 free (key);
122 free (value);
124 return (ret);
125 }
127 void cf_unregister (char *type)
128 {
129 cf_callback_t *this, *prev;
131 for (prev = NULL, this = first_callback;
132 this != NULL;
133 prev = this, this = this->next)
134 if (strcasecmp (this->type, type) == 0)
135 {
136 if (prev == NULL)
137 first_callback = this->next;
138 else
139 prev->next = this->next;
141 free (this);
142 break;
143 }
144 }
146 void cf_register (char *type,
147 int (*callback) (char *, char *),
148 char **keys, int keys_num)
149 {
150 cf_callback_t *cf_cb;
151 char buf[64];
152 int i;
154 /* Remove this module from the list, if it already exists */
155 cf_unregister (type);
157 /* This pointer will be free'd in `cf_unregister' */
158 if ((cf_cb = (cf_callback_t *) malloc (sizeof (cf_callback_t))) == NULL)
159 return;
161 cf_cb->type = type;
162 cf_cb->callback = callback;
163 cf_cb->keys = keys;
164 cf_cb->keys_num = keys_num;
166 cf_cb->next = first_callback;
167 first_callback = cf_cb;
169 for (i = 0; i < keys_num; i++)
170 {
171 if (snprintf (buf, 64, "Plugin.%s", keys[i]) < 64)
172 {
173 /* This may be called multiple times for the same
174 * `key', but apparently `lc_register_*' can handle
175 * it.. */
176 lc_register_callback (buf, SHORTOPT_NONE,
177 LC_VAR_STRING, cf_callback_general,
178 NULL);
179 }
180 else
181 {
182 DBG ("Key was truncated: `%s'", keys[i]);
183 }
184 }
185 }
187 /*
188 * Functions for the actual parsing
189 */
190 int cf_callback_general (const char *shortvar, const char *var,
191 const char *arguments, const char *value, lc_flags_t flags,
192 void *extra)
193 {
194 DBG ("shortvar = %s, var = %s, arguments = %s, value = %s, ...",
195 shortvar, var, arguments, value);
197 if ((nesting_depth == 0) || (current_module == NULL))
198 {
199 fprintf (stderr, ERR_NEEDS_SECTION, shortvar);
200 return (LC_CBRET_ERROR);
201 }
203 /* Send the data to the plugin */
204 if (cf_dispatch (current_module, shortvar, value) < 0)
205 return (LC_CBRET_ERROR);
207 return (LC_CBRET_OKAY);
208 }
210 int cf_callback_section_mode (const char *shortvar, const char *var,
211 const char *arguments, const char *value, lc_flags_t flags,
212 void *extra)
213 {
214 DBG ("shortvar = %s, var = %s, arguments = %s, value = %s, ...",
215 shortvar, var, arguments, value);
217 if (flags == LC_FLAGS_SECTIONSTART)
218 {
219 if (nesting_depth != 0)
220 {
221 fprintf (stderr, ERR_NOT_NESTED);
222 return (LC_CBRET_ERROR);
223 }
225 if (arguments == NULL)
226 {
227 fprintf (stderr, ERR_NEEDS_ARG, shortvar);
228 return (LC_CBRET_ERROR);
229 }
231 nesting_depth++;
233 if (((operating_mode == MODE_CLIENT)
234 && (strcasecmp (arguments, "Client") == 0))
235 || ((operating_mode == MODE_SERVER)
236 && (strcasecmp (arguments, "Server") == 0))
237 || ((operating_mode == MODE_LOCAL)
238 && (strcasecmp (arguments, "Local") == 0)))
239 {
240 return (LC_CBRET_OKAY);
241 }
242 else
243 {
244 return (LC_CBRET_IGNORESECTION);
245 }
246 }
247 else if (flags == LC_FLAGS_SECTIONEND)
248 {
249 nesting_depth--;
251 return (LC_CBRET_OKAY);
252 }
253 else
254 {
255 fprintf (stderr, ERR_SECTION_ONLY, shortvar);
256 return (LC_CBRET_ERROR);
257 }
259 }
261 int cf_callback_section_module (const char *shortvar, const char *var,
262 const char *arguments, const char *value, lc_flags_t flags,
263 void *extra)
264 {
265 DBG ("shortvar = %s, var = %s, arguments = %s, value = %s, ...",
266 shortvar, var, arguments, value);
268 if (flags == LC_FLAGS_SECTIONSTART)
269 {
270 if (nesting_depth != 0)
271 {
272 fprintf (stderr, ERR_NOT_NESTED);
273 return (LC_CBRET_ERROR);
274 }
276 if (arguments == NULL)
277 {
278 fprintf (stderr, ERR_NEEDS_ARG, shortvar);
279 return (LC_CBRET_ERROR);
280 }
282 if ((current_module = strdup (arguments)) == NULL)
283 {
284 perror ("strdup");
285 return (LC_CBRET_ERROR);
286 }
288 nesting_depth++;
290 if (cf_search (current_module) != NULL)
291 return (LC_CBRET_OKAY);
292 else
293 return (LC_CBRET_IGNORESECTION);
294 }
295 else if (flags == LC_FLAGS_SECTIONEND)
296 {
297 if (current_module != NULL)
298 {
299 free (current_module);
300 current_module = NULL;
301 }
303 nesting_depth--;
305 return (LC_CBRET_OKAY);
306 }
307 else
308 {
309 fprintf (stderr, ERR_SECTION_ONLY, shortvar);
310 return (LC_CBRET_ERROR);
311 }
312 }
314 int cf_callback_loadmodule (const char *shortvar, const char *var,
315 const char *arguments, const char *value, lc_flags_t flags,
316 void *extra)
317 {
318 DBG ("shortvar = %s, var = %s, arguments = %s, value = %s, ...",
319 shortvar, var, arguments, value);
321 if (nesting_depth == 0)
322 {
323 fprintf (stderr, ERR_NEEDS_SECTION, shortvar);
324 return (LC_CBRET_ERROR);
325 }
327 if (plugin_load (value))
328 syslog (LOG_ERR, "plugin_load (%s): failed to load plugin", shortvar);
330 /* Return `okay' even if there was an error, because it's not a syntax
331 * problem.. */
332 return (LC_CBRET_OKAY);
333 }
335 int cf_read (char *filename)
336 {
337 if (filename == NULL)
338 filename = CONFIGFILE;
340 lc_register_callback ("Mode", SHORTOPT_NONE, LC_VAR_SECTION,
341 cf_callback_section_mode, NULL);
342 lc_register_callback ("Plugin", SHORTOPT_NONE, LC_VAR_SECTION,
343 cf_callback_section_module, NULL);
345 /*
346 * TODO:
347 * - Add more directives, such as `DefaultMode', `DataDir', `PIDFile', ...
348 */
350 lc_register_callback ("Mode.LoadPlugin", SHORTOPT_NONE,
351 LC_VAR_STRING, cf_callback_loadmodule,
352 NULL);
354 if (lc_process_file ("collectd", filename, LC_CONF_APACHE))
355 {
356 syslog (LOG_ERR, "lc_process_file (%s): %s", filename, lc_geterrstr ());
357 return (-1);
358 }
360 /* free memory and stuff */
361 lc_cleanup ();
363 return (0);
364 }