Commit | Line | Data |
---|---|---|
c877bbd8 JO |
1 | /* |
2 | * Copyright (C) 2009, 2010 Red Hat Inc, Steven Rostedt <srostedt@redhat.com> | |
3 | * | |
4 | * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | |
5 | * This program is free software; you can redistribute it and/or | |
6 | * modify it under the terms of the GNU Lesser General Public | |
7 | * License as published by the Free Software Foundation; | |
8 | * version 2.1 of the License (not later!) | |
9 | * | |
10 | * This program is distributed in the hope that it will be useful, | |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | * GNU Lesser General Public License for more details. | |
14 | * | |
15 | * You should have received a copy of the GNU Lesser General Public | |
16 | * License along with this program; if not, see <http://www.gnu.org/licenses> | |
17 | * | |
18 | * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | |
19 | */ | |
20 | ||
5dbcfd93 | 21 | #include <ctype.h> |
5827f2fa | 22 | #include <stdio.h> |
c877bbd8 JO |
23 | #include <string.h> |
24 | #include <dlfcn.h> | |
25 | #include <stdlib.h> | |
26 | #include <sys/types.h> | |
27 | #include <sys/stat.h> | |
28 | #include <unistd.h> | |
29 | #include <dirent.h> | |
30 | #include "event-parse.h" | |
31 | #include "event-utils.h" | |
32 | ||
33 | #define LOCAL_PLUGIN_DIR ".traceevent/plugins" | |
34 | ||
5827f2fa SR |
35 | static struct registered_plugin_options { |
36 | struct registered_plugin_options *next; | |
37 | struct pevent_plugin_option *options; | |
38 | } *registered_options; | |
39 | ||
40 | static struct trace_plugin_options { | |
41 | struct trace_plugin_options *next; | |
42 | char *plugin; | |
43 | char *option; | |
44 | char *value; | |
45 | } *trace_plugin_options; | |
46 | ||
c877bbd8 JO |
47 | struct plugin_list { |
48 | struct plugin_list *next; | |
49 | char *name; | |
50 | void *handle; | |
51 | }; | |
52 | ||
5dbcfd93 SR |
53 | static void lower_case(char *str) |
54 | { | |
55 | if (!str) | |
56 | return; | |
57 | for (; *str; str++) | |
58 | *str = tolower(*str); | |
59 | } | |
60 | ||
61 | static int update_option_value(struct pevent_plugin_option *op, const char *val) | |
62 | { | |
63 | char *op_val; | |
64 | ||
65 | if (!val) { | |
66 | /* toggle, only if option is boolean */ | |
67 | if (op->value) | |
68 | /* Warn? */ | |
69 | return 0; | |
70 | op->set ^= 1; | |
71 | return 0; | |
72 | } | |
73 | ||
74 | /* | |
75 | * If the option has a value then it takes a string | |
76 | * otherwise the option is a boolean. | |
77 | */ | |
78 | if (op->value) { | |
79 | op->value = val; | |
80 | return 0; | |
81 | } | |
82 | ||
83 | /* Option is boolean, must be either "1", "0", "true" or "false" */ | |
84 | ||
85 | op_val = strdup(val); | |
86 | if (!op_val) | |
87 | return -1; | |
88 | lower_case(op_val); | |
89 | ||
90 | if (strcmp(val, "1") == 0 || strcmp(val, "true") == 0) | |
91 | op->set = 1; | |
92 | else if (strcmp(val, "0") == 0 || strcmp(val, "false") == 0) | |
93 | op->set = 0; | |
94 | free(op_val); | |
95 | ||
96 | return 0; | |
97 | } | |
98 | ||
5827f2fa SR |
99 | /** |
100 | * traceevent_plugin_list_options - get list of plugin options | |
101 | * | |
102 | * Returns an array of char strings that list the currently registered | |
103 | * plugin options in the format of <plugin>:<option>. This list can be | |
104 | * used by toggling the option. | |
105 | * | |
106 | * Returns NULL if there's no options registered. On error it returns | |
107 | * INVALID_PLUGIN_LIST_OPTION | |
108 | * | |
109 | * Must be freed with traceevent_plugin_free_options_list(). | |
110 | */ | |
111 | char **traceevent_plugin_list_options(void) | |
112 | { | |
113 | struct registered_plugin_options *reg; | |
114 | struct pevent_plugin_option *op; | |
115 | char **list = NULL; | |
116 | char *name; | |
117 | int count = 0; | |
118 | ||
119 | for (reg = registered_options; reg; reg = reg->next) { | |
120 | for (op = reg->options; op->name; op++) { | |
121 | char *alias = op->plugin_alias ? op->plugin_alias : op->file; | |
122 | char **temp = list; | |
123 | ||
124 | name = malloc(strlen(op->name) + strlen(alias) + 2); | |
125 | if (!name) | |
126 | goto err; | |
127 | ||
128 | sprintf(name, "%s:%s", alias, op->name); | |
129 | list = realloc(list, count + 2); | |
130 | if (!list) { | |
131 | list = temp; | |
132 | free(name); | |
133 | goto err; | |
134 | } | |
135 | list[count++] = name; | |
136 | list[count] = NULL; | |
137 | } | |
138 | } | |
139 | return list; | |
140 | ||
141 | err: | |
142 | while (--count >= 0) | |
143 | free(list[count]); | |
144 | free(list); | |
145 | ||
146 | return INVALID_PLUGIN_LIST_OPTION; | |
147 | } | |
148 | ||
149 | void traceevent_plugin_free_options_list(char **list) | |
150 | { | |
151 | int i; | |
152 | ||
153 | if (!list) | |
154 | return; | |
155 | ||
156 | if (list == INVALID_PLUGIN_LIST_OPTION) | |
157 | return; | |
158 | ||
159 | for (i = 0; list[i]; i++) | |
160 | free(list[i]); | |
161 | ||
162 | free(list); | |
163 | } | |
164 | ||
165 | static int | |
166 | update_option(const char *file, struct pevent_plugin_option *option) | |
167 | { | |
168 | struct trace_plugin_options *op; | |
169 | char *plugin; | |
5dbcfd93 | 170 | int ret = 0; |
5827f2fa SR |
171 | |
172 | if (option->plugin_alias) { | |
173 | plugin = strdup(option->plugin_alias); | |
174 | if (!plugin) | |
175 | return -1; | |
176 | } else { | |
177 | char *p; | |
178 | plugin = strdup(file); | |
179 | if (!plugin) | |
180 | return -1; | |
181 | p = strstr(plugin, "."); | |
182 | if (p) | |
183 | *p = '\0'; | |
184 | } | |
185 | ||
186 | /* first look for named options */ | |
187 | for (op = trace_plugin_options; op; op = op->next) { | |
188 | if (!op->plugin) | |
189 | continue; | |
190 | if (strcmp(op->plugin, plugin) != 0) | |
191 | continue; | |
192 | if (strcmp(op->option, option->name) != 0) | |
193 | continue; | |
194 | ||
5dbcfd93 SR |
195 | ret = update_option_value(option, op->value); |
196 | if (ret) | |
197 | goto out; | |
198 | break; | |
5827f2fa SR |
199 | } |
200 | ||
201 | /* first look for unnamed options */ | |
202 | for (op = trace_plugin_options; op; op = op->next) { | |
203 | if (op->plugin) | |
204 | continue; | |
205 | if (strcmp(op->option, option->name) != 0) | |
206 | continue; | |
207 | ||
5dbcfd93 | 208 | ret = update_option_value(option, op->value); |
5827f2fa SR |
209 | break; |
210 | } | |
211 | ||
212 | out: | |
213 | free(plugin); | |
5dbcfd93 | 214 | return ret; |
5827f2fa SR |
215 | } |
216 | ||
217 | /** | |
218 | * traceevent_plugin_add_options - Add a set of options by a plugin | |
219 | * @name: The name of the plugin adding the options | |
220 | * @options: The set of options being loaded | |
221 | * | |
222 | * Sets the options with the values that have been added by user. | |
223 | */ | |
224 | int traceevent_plugin_add_options(const char *name, | |
225 | struct pevent_plugin_option *options) | |
226 | { | |
227 | struct registered_plugin_options *reg; | |
228 | ||
229 | reg = malloc(sizeof(*reg)); | |
230 | if (!reg) | |
231 | return -1; | |
232 | reg->next = registered_options; | |
233 | reg->options = options; | |
234 | registered_options = reg; | |
235 | ||
236 | while (options->name) { | |
237 | update_option(name, options); | |
238 | options++; | |
239 | } | |
240 | return 0; | |
241 | } | |
242 | ||
243 | /** | |
244 | * traceevent_plugin_remove_options - remove plugin options that were registered | |
245 | * @options: Options to removed that were registered with traceevent_plugin_add_options | |
246 | */ | |
247 | void traceevent_plugin_remove_options(struct pevent_plugin_option *options) | |
248 | { | |
249 | struct registered_plugin_options **last; | |
250 | struct registered_plugin_options *reg; | |
251 | ||
252 | for (last = ®istered_options; *last; last = &(*last)->next) { | |
253 | if ((*last)->options == options) { | |
254 | reg = *last; | |
255 | *last = reg->next; | |
256 | free(reg); | |
257 | return; | |
258 | } | |
259 | } | |
260 | } | |
261 | ||
262 | /** | |
263 | * traceevent_print_plugins - print out the list of plugins loaded | |
264 | * @s: the trace_seq descripter to write to | |
265 | * @prefix: The prefix string to add before listing the option name | |
266 | * @suffix: The suffix string ot append after the option name | |
267 | * @list: The list of plugins (usually returned by traceevent_load_plugins() | |
268 | * | |
269 | * Writes to the trace_seq @s the list of plugins (files) that is | |
270 | * returned by traceevent_load_plugins(). Use @prefix and @suffix for formating: | |
271 | * @prefix = " ", @suffix = "\n". | |
272 | */ | |
273 | void traceevent_print_plugins(struct trace_seq *s, | |
274 | const char *prefix, const char *suffix, | |
275 | const struct plugin_list *list) | |
276 | { | |
277 | while (list) { | |
278 | trace_seq_printf(s, "%s%s%s", prefix, list->name, suffix); | |
279 | list = list->next; | |
280 | } | |
281 | } | |
282 | ||
c877bbd8 JO |
283 | static void |
284 | load_plugin(struct pevent *pevent, const char *path, | |
285 | const char *file, void *data) | |
286 | { | |
287 | struct plugin_list **plugin_list = data; | |
288 | pevent_plugin_load_func func; | |
289 | struct plugin_list *list; | |
290 | const char *alias; | |
291 | char *plugin; | |
292 | void *handle; | |
293 | ||
f9bb36af JO |
294 | plugin = malloc(strlen(path) + strlen(file) + 2); |
295 | if (!plugin) { | |
296 | warning("could not allocate plugin memory\n"); | |
297 | return; | |
298 | } | |
c877bbd8 JO |
299 | |
300 | strcpy(plugin, path); | |
301 | strcat(plugin, "/"); | |
302 | strcat(plugin, file); | |
303 | ||
304 | handle = dlopen(plugin, RTLD_NOW | RTLD_GLOBAL); | |
305 | if (!handle) { | |
306 | warning("could not load plugin '%s'\n%s\n", | |
307 | plugin, dlerror()); | |
308 | goto out_free; | |
309 | } | |
310 | ||
311 | alias = dlsym(handle, PEVENT_PLUGIN_ALIAS_NAME); | |
312 | if (!alias) | |
313 | alias = file; | |
314 | ||
315 | func = dlsym(handle, PEVENT_PLUGIN_LOADER_NAME); | |
316 | if (!func) { | |
317 | warning("could not find func '%s' in plugin '%s'\n%s\n", | |
318 | PEVENT_PLUGIN_LOADER_NAME, plugin, dlerror()); | |
319 | goto out_free; | |
320 | } | |
321 | ||
f9bb36af JO |
322 | list = malloc(sizeof(*list)); |
323 | if (!list) { | |
324 | warning("could not allocate plugin memory\n"); | |
325 | goto out_free; | |
326 | } | |
327 | ||
c877bbd8 JO |
328 | list->next = *plugin_list; |
329 | list->handle = handle; | |
330 | list->name = plugin; | |
331 | *plugin_list = list; | |
332 | ||
333 | pr_stat("registering plugin: %s", plugin); | |
334 | func(pevent); | |
335 | return; | |
336 | ||
337 | out_free: | |
338 | free(plugin); | |
339 | } | |
340 | ||
341 | static void | |
342 | load_plugins_dir(struct pevent *pevent, const char *suffix, | |
343 | const char *path, | |
344 | void (*load_plugin)(struct pevent *pevent, | |
345 | const char *path, | |
346 | const char *name, | |
347 | void *data), | |
348 | void *data) | |
349 | { | |
350 | struct dirent *dent; | |
351 | struct stat st; | |
352 | DIR *dir; | |
353 | int ret; | |
354 | ||
355 | ret = stat(path, &st); | |
356 | if (ret < 0) | |
357 | return; | |
358 | ||
359 | if (!S_ISDIR(st.st_mode)) | |
360 | return; | |
361 | ||
362 | dir = opendir(path); | |
363 | if (!dir) | |
364 | return; | |
365 | ||
366 | while ((dent = readdir(dir))) { | |
367 | const char *name = dent->d_name; | |
368 | ||
369 | if (strcmp(name, ".") == 0 || | |
370 | strcmp(name, "..") == 0) | |
371 | continue; | |
372 | ||
373 | /* Only load plugins that end in suffix */ | |
374 | if (strcmp(name + (strlen(name) - strlen(suffix)), suffix) != 0) | |
375 | continue; | |
376 | ||
377 | load_plugin(pevent, path, name, data); | |
378 | } | |
379 | ||
380 | closedir(dir); | |
381 | } | |
382 | ||
383 | static void | |
384 | load_plugins(struct pevent *pevent, const char *suffix, | |
385 | void (*load_plugin)(struct pevent *pevent, | |
386 | const char *path, | |
387 | const char *name, | |
388 | void *data), | |
389 | void *data) | |
390 | { | |
391 | char *home; | |
392 | char *path; | |
393 | char *envdir; | |
394 | ||
a7c3196c SRRH |
395 | if (pevent->flags & PEVENT_DISABLE_PLUGINS) |
396 | return; | |
397 | ||
c877bbd8 JO |
398 | /* |
399 | * If a system plugin directory was defined, | |
400 | * check that first. | |
401 | */ | |
402 | #ifdef PLUGIN_DIR | |
a7c3196c SRRH |
403 | if (!(pevent->flags & PEVENT_DISABLE_SYS_PLUGINS)) |
404 | load_plugins_dir(pevent, suffix, PLUGIN_DIR, | |
405 | load_plugin, data); | |
c877bbd8 JO |
406 | #endif |
407 | ||
408 | /* | |
409 | * Next let the environment-set plugin directory | |
410 | * override the system defaults. | |
411 | */ | |
412 | envdir = getenv("TRACEEVENT_PLUGIN_DIR"); | |
413 | if (envdir) | |
414 | load_plugins_dir(pevent, suffix, envdir, load_plugin, data); | |
415 | ||
416 | /* | |
417 | * Now let the home directory override the environment | |
418 | * or system defaults. | |
419 | */ | |
420 | home = getenv("HOME"); | |
421 | if (!home) | |
422 | return; | |
423 | ||
f9bb36af JO |
424 | path = malloc(strlen(home) + strlen(LOCAL_PLUGIN_DIR) + 2); |
425 | if (!path) { | |
426 | warning("could not allocate plugin memory\n"); | |
427 | return; | |
428 | } | |
c877bbd8 JO |
429 | |
430 | strcpy(path, home); | |
431 | strcat(path, "/"); | |
432 | strcat(path, LOCAL_PLUGIN_DIR); | |
433 | ||
434 | load_plugins_dir(pevent, suffix, path, load_plugin, data); | |
435 | ||
436 | free(path); | |
437 | } | |
438 | ||
439 | struct plugin_list* | |
440 | traceevent_load_plugins(struct pevent *pevent) | |
441 | { | |
442 | struct plugin_list *list = NULL; | |
443 | ||
444 | load_plugins(pevent, ".so", load_plugin, &list); | |
445 | return list; | |
446 | } | |
447 | ||
448 | void | |
8d0c2224 | 449 | traceevent_unload_plugins(struct plugin_list *plugin_list, struct pevent *pevent) |
c877bbd8 JO |
450 | { |
451 | pevent_plugin_unload_func func; | |
452 | struct plugin_list *list; | |
453 | ||
454 | while (plugin_list) { | |
455 | list = plugin_list; | |
456 | plugin_list = list->next; | |
457 | func = dlsym(list->handle, PEVENT_PLUGIN_UNLOADER_NAME); | |
458 | if (func) | |
8d0c2224 | 459 | func(pevent); |
c877bbd8 JO |
460 | dlclose(list->handle); |
461 | free(list->name); | |
462 | free(list); | |
463 | } | |
464 | } |