src/core/plugin.c

   1 /*
   2  * SysDB - src/core/plugin.c
   3  * Copyright (C) 2012 Sebastian 'tokkee' Harl <sh@tokkee.org>
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  16  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  17  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  18  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
  19  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  20  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  22  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  23  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  24  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  25  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #include "sysdb.h"
  29 #include "core/plugin.h"
  30 #include "utils/error.h"
  31 #include "utils/llist.h"
  32 #include "utils/time.h"
  33
  34 #include <assert.h>
  35
  36 #include <errno.h>
  37
  38 #include <stdarg.h>
  39 #include <stdio.h>
  40 #include <string.h>
  41 #include <strings.h>
  42 #include <unistd.h>
  43
  44 #include <ltdl.h>
  45
  46 #include <pthread.h>
  47
  48 /*
  49  * private data types
  50  */
  51
  52 struct sdb_plugin_info {
  53         char *name;
  54
  55         char *description;
  56         char *copyright;
  57         char *license;
  58
  59         int   version;
  60         int   plugin_version;
  61 };
  62 #define SDB_PLUGIN_INFO_INIT { "no name set", "no description set", \
  63         /* copyright */ "", /* license */ "", \
  64         /* version */ -1, /* plugin_version */ -1 }
  65
  66 typedef struct {
  67         sdb_object_t super;
  68         char cb_name[64];
  69         void *cb_callback;
  70         sdb_object_t *cb_user_data;
  71         sdb_plugin_ctx_t cb_ctx;
  72 } sdb_plugin_cb_t;
  73 #define SDB_PLUGIN_CB_INIT { SDB_OBJECT_INIT, /* name = */ "", \
  74         /* callback = */ NULL, /* user_data = */ NULL, \
  75         SDB_PLUGIN_CTX_INIT }
  76
  77 typedef struct {
  78         sdb_plugin_cb_t super;
  79 #define ccb_name super.cb_name
  80 #define ccb_callback super.cb_callback
  81 #define ccb_user_data super.cb_user_data
  82 #define ccb_ctx super.cb_ctx
  83         sdb_time_t ccb_interval;
  84         sdb_time_t ccb_next_update;
  85 } sdb_plugin_collector_cb_t;
  86
  87 #define SDB_PLUGIN_CB(obj) ((sdb_plugin_cb_t *)(obj))
  88 #define SDB_PLUGIN_CCB(obj) ((sdb_plugin_collector_cb_t *)(obj))
  89
  90 /*
  91  * private variables
  92  */
  93
  94 static sdb_plugin_ctx_t  plugin_default_ctx = SDB_PLUGIN_CTX_INIT;
  95
  96 static pthread_key_t    plugin_ctx_key;
  97 static _Bool            plugin_ctx_key_initialized = 0;
  98
  99 static sdb_llist_t      *config_list = NULL;
 100 static sdb_llist_t      *init_list = NULL;
 101 static sdb_llist_t      *collector_list = NULL;
 102 static sdb_llist_t      *shutdown_list = NULL;
 103
 104 /*
 105  * private helper functions
 106  */
 107
 108 static void
 109 sdb_plugin_ctx_destructor(void *ctx)
 110 {
 111         if (! ctx)
 112                 return;
 113         free(ctx);
 114 } /* sdb_plugin_ctx_destructor */
 115
 116 static void
 117 sdb_plugin_ctx_init(void)
 118 {
 119         if (plugin_ctx_key_initialized)
 120                 return;
 121
 122         pthread_key_create(&plugin_ctx_key, sdb_plugin_ctx_destructor);
 123         plugin_ctx_key_initialized = 1;
 124 } /* sdb_plugin_ctx_init */
 125
 126 static sdb_plugin_ctx_t *
 127 sdb_plugin_ctx_create(void)
 128 {
 129         sdb_plugin_ctx_t *ctx;
 130
 131         ctx = malloc(sizeof(*ctx));
 132         if (! ctx)
 133                 return NULL;
 134
 135         *ctx = plugin_default_ctx;
 136
 137         if (! plugin_ctx_key_initialized)
 138                 sdb_plugin_ctx_init();
 139         pthread_setspecific(plugin_ctx_key, ctx);
 140         return ctx;
 141 } /* sdb_plugin_ctx_create */
 142
 143 static int
 144 sdb_plugin_cmp_name(const sdb_object_t *a, const sdb_object_t *b)
 145 {
 146         const sdb_plugin_cb_t *cb1 = (const sdb_plugin_cb_t *)a;
 147         const sdb_plugin_cb_t *cb2 = (const sdb_plugin_cb_t *)b;
 148
 149         assert(cb1 && cb2);
 150         return strcasecmp(cb1->cb_name, cb2->cb_name);
 151 } /* sdb_plugin_cmp_name */
 152
 153 static int
 154 sdb_plugin_cmp_next_update(const sdb_object_t *a, const sdb_object_t *b)
 155 {
 156         const sdb_plugin_collector_cb_t *ccb1
 157                 = (const sdb_plugin_collector_cb_t *)a;
 158         const sdb_plugin_collector_cb_t *ccb2
 159                 = (const sdb_plugin_collector_cb_t *)b;
 160
 161         assert(ccb1 && ccb2);
 162
 163         return (ccb1->ccb_next_update > ccb2->ccb_next_update)
 164                 ? 1 : (ccb1->ccb_next_update < ccb2->ccb_next_update)
 165                 ? -1 : 0;
 166 } /* sdb_plugin_cmp_next_update */
 167
 168 static sdb_plugin_cb_t *
 169 sdb_plugin_find_by_name(sdb_llist_t *list, const char *name)
 170 {
 171         sdb_plugin_cb_t tmp = SDB_PLUGIN_CB_INIT;
 172
 173         sdb_object_t *obj;
 174         assert(name);
 175
 176         if (! list)
 177                 return NULL;
 178
 179         snprintf(tmp.cb_name, sizeof(tmp.cb_name), "%s", name);
 180         tmp.cb_name[sizeof(tmp.cb_name) - 1] = '\0';
 181         obj = sdb_llist_search(list, SDB_OBJ(&tmp), sdb_plugin_cmp_name);
 182         if (! obj)
 183                 return NULL;
 184         return SDB_PLUGIN_CB(obj);
 185 } /* sdb_plugin_find_by_name */
 186
 187 static int
 188 sdb_plugin_cb_init(sdb_object_t *obj, va_list ap)
 189 {
 190         sdb_llist_t **list = va_arg(ap, sdb_llist_t **);
 191         const char  *type = va_arg(ap, const char *);
 192         const char  *name = va_arg(ap, const char *);
 193         void    *callback = va_arg(ap, void *);
 194         sdb_object_t   *ud = va_arg(ap, sdb_object_t *);
 195
 196         assert(list);
 197         assert(type);
 198         assert(obj);
 199
 200         if (sdb_plugin_find_by_name(*list, name)) {
 201                 sdb_log(SDB_LOG_WARNING, "plugin: %s callback '%s' "
 202                                 "has already been registered. Ignoring newly "
 203                                 "registered version.\n", type, name);
 204                 return -1;
 205         }
 206
 207         snprintf(SDB_PLUGIN_CB(obj)->cb_name,
 208                         sizeof(SDB_PLUGIN_CB(obj)->cb_name),
 209                         "%s", name);
 210         SDB_PLUGIN_CB(obj)->cb_name[sizeof(SDB_PLUGIN_CB(obj)->cb_name) - 1] = '\0';
 211         SDB_PLUGIN_CB(obj)->cb_callback = callback;
 212         SDB_PLUGIN_CB(obj)->cb_ctx      = sdb_plugin_get_ctx();
 213
 214         sdb_object_ref(ud);
 215         SDB_PLUGIN_CB(obj)->cb_user_data = ud;
 216         return 0;
 217 } /* sdb_plugin_cb_init */
 218
 219 static void
 220 sdb_plugin_cb_destroy(sdb_object_t *obj)
 221 {
 222         assert(obj);
 223         sdb_object_deref(SDB_PLUGIN_CB(obj)->cb_user_data);
 224 } /* sdb_plugin_cb_destroy */
 225
 226 static int
 227 sdb_plugin_add_callback(sdb_llist_t **list, const char *type,
 228                 const char *name, void *callback, sdb_object_t *user_data)
 229 {
 230         sdb_object_t *obj;
 231
 232         if ((! name) || (! callback))
 233                 return -1;
 234
 235         assert(list);
 236
 237         if (! *list)
 238                 *list = sdb_llist_create();
 239         if (! *list)
 240                 return -1;
 241
 242         obj = sdb_object_create(sizeof(sdb_plugin_cb_t), sdb_plugin_cb_init,
 243                         sdb_plugin_cb_destroy, list, type, name, callback, user_data);
 244         if (! obj)
 245                 return -1;
 246
 247         if (sdb_llist_append(*list, obj)) {
 248                 sdb_object_deref(obj);
 249                 return -1;
 250         }
 251
 252         /* pass control to the list */
 253         sdb_object_deref(obj);
 254
 255         sdb_log(SDB_LOG_INFO, "plugin: Registered %s callback '%s'.\n",
 256                         type, name);
 257         return 0;
 258 } /* sdb_plugin_add_callback */
 259
 260 /*
 261  * public API
 262  */
 263
 264 int
 265 sdb_plugin_load(const char *name)
 266 {
 267         char  real_name[strlen(name) > 0 ? strlen(name) : 1];
 268         const char *name_ptr;
 269         char *tmp;
 270
 271         char filename[1024];
 272
 273         lt_dlhandle lh;
 274
 275         int (*mod_init)(sdb_plugin_info_t *);
 276         sdb_plugin_info_t plugin_info = SDB_PLUGIN_INFO_INIT;
 277
 278         int status;
 279
 280         if ((! name) || (! *name))
 281                 return -1;
 282
 283         real_name[0] = '\0';
 284         name_ptr = name;
 285
 286         while ((tmp = strstr(name_ptr, "::"))) {
 287                 strncat(real_name, name_ptr, (size_t)(tmp - name_ptr));
 288                 strcat(real_name, "/");
 289                 name_ptr = tmp + strlen("::");
 290         }
 291         strcat(real_name, name_ptr);
 292
 293         snprintf(filename, sizeof(filename), "%s/%s.so",
 294                         PKGLIBDIR, real_name);
 295         filename[sizeof(filename) - 1] = '\0';
 296
 297         if (access(filename, R_OK)) {
 298                 char errbuf[1024];
 299                 sdb_log(SDB_LOG_ERR, "plugin: Failed to load plugin '%s' (%s): %s\n",
 300                                 name, filename, sdb_strerror(errno, errbuf, sizeof(errbuf)));
 301                 return -1;
 302         }
 303
 304         lt_dlinit();
 305         lt_dlerror();
 306
 307         lh = lt_dlopen(filename);
 308         if (! lh) {
 309                 sdb_log(SDB_LOG_ERR, "plugin: Failed to load plugin '%s': %s\n"
 310                                 "The most common cause for this problem are missing "
 311                                 "dependencies.\n", name, lt_dlerror());
 312                 return -1;
 313         }
 314
 315         mod_init = (int (*)(sdb_plugin_info_t *))lt_dlsym(lh, "sdb_module_init");
 316         if (! mod_init) {
 317                 sdb_log(SDB_LOG_ERR, "plugin: Failed to load plugin '%s': "
 318                                 "could not find symbol 'sdb_module_init'\n", name);
 319                 return -1;
 320         }
 321
 322         status = mod_init(&plugin_info);
 323         if (status) {
 324                 sdb_log(SDB_LOG_ERR, "plugin: Failed to initialize "
 325                                 "plugin '%s'\n", name);
 326                 return -1;
 327         }
 328
 329         /* compare minor version */
 330         if ((plugin_info.version < 0)
 331                         || ((int)(plugin_info.version / 100) != (int)(SDB_VERSION / 100)))
 332                 sdb_log(SDB_LOG_WARNING, "plugin: WARNING: version of "
 333                                 "plugin '%s' (%i.%i.%i) does not match our version "
 334                                 "(%i.%i.%i); this might cause problems\n",
 335                                 name, SDB_VERSION_DECODE(plugin_info.version),
 336                                 SDB_VERSION_DECODE(SDB_VERSION));
 337
 338         sdb_log(SDB_LOG_INFO, "plugin: Successfully loaded "
 339                         "plugin '%s' v%i (%s)\n\t%s\n",
 340                         plugin_info.name, plugin_info.plugin_version,
 341                         plugin_info.description, plugin_info.copyright);
 342         return 0;
 343 } /* sdb_plugin_load */
 344
 345 int
 346 sdb_plugin_set_info(sdb_plugin_info_t *info, int type, ...)
 347 {
 348         va_list ap;
 349
 350         if (! info)
 351                 return -1;
 352
 353         va_start(ap, type);
 354
 355         switch (type) {
 356                 case SDB_PLUGIN_INFO_NAME:
 357                         {
 358                                 char *name = va_arg(ap, char *);
 359                                 info->name = name;
 360                         }
 361                         break;
 362                 case SDB_PLUGIN_INFO_DESC:
 363                         {
 364                                 char *desc = va_arg(ap, char *);
 365                                 info->description = desc;
 366                         }
 367                         break;
 368                 case SDB_PLUGIN_INFO_COPYRIGHT:
 369                         {
 370                                 char *copyright = va_arg(ap, char *);
 371                                 info->copyright = copyright;
 372                         }
 373                         break;
 374                 case SDB_PLUGIN_INFO_LICENSE:
 375                         {
 376                                 char *license = va_arg(ap, char *);
 377                                 info->license = license;
 378                         }
 379                         break;
 380                 case SDB_PLUGIN_INFO_VERSION:
 381                         {
 382                                 int version = va_arg(ap, int);
 383                                 info->version = version;
 384                         }
 385                         break;
 386                 case SDB_PLUGIN_INFO_PLUGIN_VERSION:
 387                         {
 388                                 int version = va_arg(ap, int);
 389                                 info->plugin_version = version;
 390                         }
 391                         break;
 392                 default:
 393                         va_end(ap);
 394                         return -1;
 395         }
 396
 397         va_end(ap);
 398         return 0;
 399 } /* sdb_plugin_set_info */
 400
 401 int
 402 sdb_plugin_register_config(const char *name, sdb_plugin_config_cb callback)
 403 {
 404         return sdb_plugin_add_callback(&config_list, "init", name,
 405                         callback, NULL);
 406 } /* sdb_plugin_register_config */
 407
 408 int
 409 sdb_plugin_register_init(const char *name, sdb_plugin_init_cb callback,
 410                 sdb_object_t *user_data)
 411 {
 412         return sdb_plugin_add_callback(&init_list, "init", name,
 413                         callback, user_data);
 414 } /* sdb_plugin_register_init */
 415
 416 int
 417 sdb_plugin_register_shutdown(const char *name, sdb_plugin_shutdown_cb callback,
 418                 sdb_object_t *user_data)
 419 {
 420         return sdb_plugin_add_callback(&shutdown_list, "shutdown", name,
 421                         callback, user_data);
 422 } /* sdb_plugin_register_shutdown */
 423
 424 int
 425 sdb_plugin_register_collector(const char *name, sdb_plugin_collector_cb callback,
 426                 const sdb_time_t *interval, sdb_object_t *user_data)
 427 {
 428         sdb_object_t *obj;
 429
 430         if ((! name) || (! callback))
 431                 return -1;
 432
 433         if (! collector_list)
 434                 collector_list = sdb_llist_create();
 435         if (! collector_list)
 436                 return -1;
 437
 438         obj = sdb_object_create(sizeof(sdb_plugin_collector_cb_t),
 439                         sdb_plugin_cb_init, sdb_plugin_cb_destroy,
 440                         &collector_list, "collector", name, callback, user_data);
 441         if (! obj)
 442                 return -1;
 443
 444         if (interval)
 445                 SDB_PLUGIN_CCB(obj)->ccb_interval = *interval;
 446         else {
 447                 sdb_time_t tmp = sdb_plugin_get_ctx().interval;
 448
 449                 if (tmp > 0)
 450                         SDB_PLUGIN_CCB(obj)->ccb_interval = tmp;
 451                 else
 452                         SDB_PLUGIN_CCB(obj)->ccb_interval = 0;
 453         }
 454
 455         if (! (SDB_PLUGIN_CCB(obj)->ccb_next_update = sdb_gettime())) {
 456                 char errbuf[1024];
 457                 sdb_log(SDB_LOG_ERR, "plugin: Failed to determine current "
 458                                 "time: %s\n", sdb_strerror(errno, errbuf, sizeof(errbuf)));
 459                 sdb_object_deref(obj);
 460                 return -1;
 461         }
 462
 463         if (sdb_llist_insert_sorted(collector_list, obj,
 464                                 sdb_plugin_cmp_next_update)) {
 465                 sdb_object_deref(obj);
 466                 return -1;
 467         }
 468
 469         /* pass control to the list */
 470         sdb_object_deref(obj);
 471
 472         sdb_log(SDB_LOG_INFO, "plugin: Registered collector callback '%s' "
 473                         "(interval = %.3fs).\n", name,
 474                         SDB_TIME_TO_DOUBLE(SDB_PLUGIN_CCB(obj)->ccb_interval));
 475         return 0;
 476 } /* sdb_plugin_register_collector */
 477
 478 sdb_plugin_ctx_t
 479 sdb_plugin_get_ctx(void)
 480 {
 481         sdb_plugin_ctx_t *ctx;
 482
 483         if (! plugin_ctx_key_initialized)
 484                 sdb_plugin_ctx_init();
 485         ctx = pthread_getspecific(plugin_ctx_key);
 486
 487         if (! ctx)
 488                 ctx = sdb_plugin_ctx_create();
 489         if (! ctx)
 490                 return plugin_default_ctx;
 491         return *ctx;
 492 } /* sdb_plugin_get_ctx */
 493
 494 sdb_plugin_ctx_t
 495 sdb_plugin_set_ctx(sdb_plugin_ctx_t ctx)
 496 {
 497         sdb_plugin_ctx_t *tmp;
 498         sdb_plugin_ctx_t old;
 499
 500         if (! plugin_ctx_key_initialized)
 501                 sdb_plugin_ctx_init();
 502         tmp = pthread_getspecific(plugin_ctx_key);
 503
 504         if (! tmp)
 505                 tmp = sdb_plugin_ctx_create();
 506         if (! tmp)
 507                 return plugin_default_ctx;
 508
 509         old = *tmp;
 510         *tmp = ctx;
 511         return old;
 512 } /* sdb_plugin_set_ctx */
 513
 514 int
 515 sdb_plugin_configure(const char *name, oconfig_item_t *ci)
 516 {
 517         sdb_plugin_cb_t *plugin;
 518         sdb_plugin_config_cb callback;
 519
 520         sdb_plugin_ctx_t old_ctx;
 521
 522         int status;
 523
 524         if ((! name) || (! ci))
 525                 return -1;
 526
 527         plugin = sdb_plugin_find_by_name(config_list, name);
 528         if (! plugin) {
 529                 /* XXX: check if any such plugin has been loaded */
 530                 sdb_log(SDB_LOG_ERR, "plugin: Plugin '%s' did not register "
 531                                 "a config callback.\n", name);
 532                 errno = ENOENT;
 533                 return -1;
 534         }
 535
 536         old_ctx = sdb_plugin_set_ctx(plugin->cb_ctx);
 537         callback = plugin->cb_callback;
 538         status = callback(ci);
 539         sdb_plugin_set_ctx(old_ctx);
 540         return status;
 541 } /* sdb_plugin_configure */
 542
 543 int
 544 sdb_plugin_init_all(void)
 545 {
 546         sdb_llist_iter_t *iter;
 547
 548         iter = sdb_llist_get_iter(init_list);
 549         while (sdb_llist_iter_has_next(iter)) {
 550                 sdb_plugin_init_cb callback;
 551                 sdb_plugin_ctx_t old_ctx;
 552
 553                 sdb_object_t *obj = sdb_llist_iter_get_next(iter);
 554                 assert(obj);
 555
 556                 callback = SDB_PLUGIN_CB(obj)->cb_callback;
 557
 558                 old_ctx = sdb_plugin_set_ctx(SDB_PLUGIN_CB(obj)->cb_ctx);
 559                 if (callback(SDB_PLUGIN_CB(obj)->cb_user_data)) {
 560                         /* XXX: unload plugin */
 561                 }
 562                 sdb_plugin_set_ctx(old_ctx);
 563         }
 564         return 0;
 565 } /* sdb_plugin_init_all */
 566
 567 int
 568 sdb_plugin_collector_loop(sdb_plugin_loop_t *loop)
 569 {
 570         if ((! collector_list) || (! loop))
 571                 return -1;
 572
 573         while (loop->do_loop) {
 574                 sdb_plugin_collector_cb callback;
 575                 sdb_plugin_ctx_t old_ctx;
 576
 577                 sdb_time_t interval, now;
 578
 579                 sdb_object_t *obj = sdb_llist_shift(collector_list);
 580                 if (! obj)
 581                         return -1;
 582
 583                 callback = SDB_PLUGIN_CCB(obj)->ccb_callback;
 584
 585                 if (! (now = sdb_gettime())) {
 586                         char errbuf[1024];
 587                         sdb_log(SDB_LOG_ERR, "plugin: Failed to determine current "
 588                                         "time: %s\n", sdb_strerror(errno, errbuf, sizeof(errbuf)));
 589                         now = SDB_PLUGIN_CCB(obj)->ccb_next_update;
 590                 }
 591
 592                 if (now < SDB_PLUGIN_CCB(obj)->ccb_next_update) {
 593                         interval = SDB_PLUGIN_CCB(obj)->ccb_next_update - now;
 594
 595                         errno = 0;
 596                         while (loop->do_loop && sdb_sleep(interval, &interval)) {
 597                                 if (errno != EINTR) {
 598                                         char errbuf[1024];
 599                                         sdb_log(SDB_LOG_ERR, "plugin: Failed to sleep: %s\n",
 600                                                         sdb_strerror(errno, errbuf, sizeof(errbuf)));
 601                                         return -1;
 602                                 }
 603                                 errno = 0;
 604                         }
 605
 606                         if (! loop->do_loop)
 607                                 return 0;
 608                 }
 609
 610                 old_ctx = sdb_plugin_set_ctx(SDB_PLUGIN_CCB(obj)->ccb_ctx);
 611                 if (callback(SDB_PLUGIN_CCB(obj)->ccb_user_data)) {
 612                         /* XXX */
 613                 }
 614                 sdb_plugin_set_ctx(old_ctx);
 615
 616                 interval = SDB_PLUGIN_CCB(obj)->ccb_interval;
 617                 if (! interval)
 618                         interval = loop->default_interval;
 619                 if (! interval) {
 620                         sdb_log(SDB_LOG_WARNING, "plugin: No interval configured "
 621                                         "for plugin '%s'; skipping any further "
 622                                         "iterations.\n", SDB_PLUGIN_CCB(obj)->ccb_name);
 623                         sdb_object_deref(obj);
 624                         continue;
 625                 }
 626
 627                 SDB_PLUGIN_CCB(obj)->ccb_next_update += interval;
 628
 629                 if (! (now = sdb_gettime())) {
 630                         char errbuf[1024];
 631                         sdb_log(SDB_LOG_ERR, "plugin: Failed to determine current "
 632                                         "time: %s\n", sdb_strerror(errno, errbuf, sizeof(errbuf)));
 633                         now = SDB_PLUGIN_CCB(obj)->ccb_next_update;
 634                 }
 635
 636                 if (now > SDB_PLUGIN_CCB(obj)->ccb_next_update) {
 637                         sdb_log(SDB_LOG_WARNING, "plugin: Plugin '%s' took too "
 638                                         "long; skipping iterations to keep up.\n",
 639                                         SDB_PLUGIN_CCB(obj)->ccb_name);
 640                         SDB_PLUGIN_CCB(obj)->ccb_next_update = now;
 641                 }
 642
 643                 if (sdb_llist_insert_sorted(collector_list, obj,
 644                                         sdb_plugin_cmp_next_update)) {
 645                         sdb_log(SDB_LOG_ERR, "plugin: Failed to re-insert "
 646                                         "plugin '%s' into collector list. Unable to further "
 647                                         "use the plugin.\n",
 648                                         SDB_PLUGIN_CCB(obj)->ccb_name);
 649                         sdb_object_deref(obj);
 650                         return -1;
 651                 }
 652
 653                 /* pass control back to the list */
 654                 sdb_object_deref(obj);
 655         }
 656         return 0;
 657 } /* sdb_plugin_read_loop */
 658
 659 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 660