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 "core/error.h"
  31 #include "core/time.h"
  32 #include "utils/llist.h"
  33 #include "utils/strbuf.h"
  34
  35 #include <assert.h>
  36
  37 #include <errno.h>
  38
  39 #include <stdarg.h>
  40 #include <stdio.h>
  41 #include <string.h>
  42 #include <strings.h>
  43 #include <unistd.h>
  44
  45 #include <ltdl.h>
  46
  47 #include <pthread.h>
  48
  49 /*
  50  * private data types
  51  */
  52
  53 struct sdb_plugin_info {
  54         char *name;
  55
  56         char *description;
  57         char *copyright;
  58         char *license;
  59
  60         int   version;
  61         int   plugin_version;
  62 };
  63 #define SDB_PLUGIN_INFO_INIT { /* name */ NULL, /* desc */ NULL, \
  64         /* copyright */ NULL, /* license */ NULL, \
  65         /* version */ -1, /* plugin_version */ -1 }
  66 #define INFO_GET(i, attr) \
  67         ((i)->attr ? (i)->attr : #attr" not set")
  68
  69 typedef struct {
  70         sdb_object_t super;
  71         void *cb_callback;
  72         sdb_object_t *cb_user_data;
  73         sdb_plugin_ctx_t cb_ctx;
  74 } sdb_plugin_cb_t;
  75 #define SDB_PLUGIN_CB_INIT { SDB_OBJECT_INIT, \
  76         /* callback = */ NULL, /* user_data = */ NULL, \
  77         SDB_PLUGIN_CTX_INIT }
  78
  79 typedef struct {
  80         sdb_plugin_cb_t super;
  81 #define ccb_callback super.cb_callback
  82 #define ccb_user_data super.cb_user_data
  83 #define ccb_ctx super.cb_ctx
  84         sdb_time_t ccb_interval;
  85         sdb_time_t ccb_next_update;
  86 } sdb_plugin_collector_cb_t;
  87
  88 #define SDB_PLUGIN_CB(obj) ((sdb_plugin_cb_t *)(obj))
  89 #define SDB_PLUGIN_CCB(obj) ((sdb_plugin_collector_cb_t *)(obj))
  90
  91 typedef struct {
  92         sdb_object_t super;
  93         sdb_plugin_ctx_t public;
  94 } ctx_t;
  95 #define CTX_INIT { SDB_OBJECT_INIT, \
  96         SDB_PLUGIN_CTX_INIT }
  97
  98 #define CTX(obj) ((ctx_t *)(obj))
  99
 100 /*
 101  * private variables
 102  */
 103
 104 static sdb_plugin_ctx_t  plugin_default_ctx = SDB_PLUGIN_CTX_INIT;
 105
 106 static pthread_key_t     plugin_ctx_key;
 107 static _Bool             plugin_ctx_key_initialized = 0;
 108
 109 static sdb_llist_t      *config_list = NULL;
 110 static sdb_llist_t      *init_list = NULL;
 111 static sdb_llist_t      *collector_list = NULL;
 112 static sdb_llist_t      *cname_list = NULL;
 113 static sdb_llist_t      *shutdown_list = NULL;
 114 static sdb_llist_t      *log_list = NULL;
 115
 116 /*
 117  * private helper functions
 118  */
 119
 120 static void
 121 sdb_plugin_info_clear(sdb_plugin_info_t *info)
 122 {
 123         sdb_plugin_info_t empty_info = SDB_PLUGIN_INFO_INIT;
 124         if (! info)
 125                 return;
 126
 127         if (info->name)
 128                 free(info->name);
 129         if (info->description)
 130                 free(info->description);
 131         if (info->copyright)
 132                 free(info->copyright);
 133         if (info->license)
 134                 free(info->license);
 135
 136         *info = empty_info;
 137 } /* sdb_plugin_info_clear */
 138
 139 static void
 140 ctx_destructor(void *c)
 141 {
 142         sdb_object_deref(SDB_OBJ(c));
 143 } /* ctx_destructor */
 144
 145 static void
 146 ctx_key_init(void)
 147 {
 148         if (plugin_ctx_key_initialized)
 149                 return;
 150
 151         pthread_key_create(&plugin_ctx_key, ctx_destructor);
 152         plugin_ctx_key_initialized = 1;
 153 } /* ctx_key_init */
 154
 155 static int
 156 sdb_plugin_cmp_next_update(const sdb_object_t *a, const sdb_object_t *b)
 157 {
 158         const sdb_plugin_collector_cb_t *ccb1
 159                 = (const sdb_plugin_collector_cb_t *)a;
 160         const sdb_plugin_collector_cb_t *ccb2
 161                 = (const sdb_plugin_collector_cb_t *)b;
 162
 163         assert(ccb1 && ccb2);
 164
 165         return (ccb1->ccb_next_update > ccb2->ccb_next_update)
 166                 ? 1 : (ccb1->ccb_next_update < ccb2->ccb_next_update)
 167                 ? -1 : 0;
 168 } /* sdb_plugin_cmp_next_update */
 169
 170 /*
 171  * private types
 172  */
 173
 174 static int
 175 ctx_init(sdb_object_t *obj, va_list __attribute__((unused)) ap)
 176 {
 177         ctx_t *ctx = CTX(obj);
 178
 179         assert(ctx);
 180
 181         ctx->public = plugin_default_ctx;
 182         return 0;
 183 } /* ctx_init */
 184
 185 static sdb_type_t ctx_type = {
 186         sizeof(ctx_t),
 187
 188         ctx_init,
 189         NULL
 190 };
 191
 192 static ctx_t *
 193 ctx_create(void)
 194 {
 195         ctx_t *ctx;
 196
 197         ctx = CTX(sdb_object_create("plugin-context", ctx_type));
 198         if (! ctx)
 199                 return NULL;
 200
 201         if (! plugin_ctx_key_initialized)
 202                 ctx_key_init();
 203         pthread_setspecific(plugin_ctx_key, ctx);
 204         return ctx;
 205 } /* ctx_create */
 206
 207 static int
 208 sdb_plugin_cb_init(sdb_object_t *obj, va_list ap)
 209 {
 210         sdb_llist_t **list = va_arg(ap, sdb_llist_t **);
 211         const char   *type = va_arg(ap, const char *);
 212         void     *callback = va_arg(ap, void *);
 213         sdb_object_t   *ud = va_arg(ap, sdb_object_t *);
 214
 215         assert(list);
 216         assert(type);
 217         assert(obj);
 218
 219         if (sdb_llist_search_by_name(*list, obj->name)) {
 220                 sdb_log(SDB_LOG_WARNING, "plugin: %s callback '%s' "
 221                                 "has already been registered. Ignoring newly "
 222                                 "registered version.", type, obj->name);
 223                 return -1;
 224         }
 225
 226         SDB_PLUGIN_CB(obj)->cb_callback = callback;
 227         SDB_PLUGIN_CB(obj)->cb_ctx      = sdb_plugin_get_ctx();
 228
 229         sdb_object_ref(ud);
 230         SDB_PLUGIN_CB(obj)->cb_user_data = ud;
 231         return 0;
 232 } /* sdb_plugin_cb_init */
 233
 234 static void
 235 sdb_plugin_cb_destroy(sdb_object_t *obj)
 236 {
 237         assert(obj);
 238         sdb_object_deref(SDB_PLUGIN_CB(obj)->cb_user_data);
 239 } /* sdb_plugin_cb_destroy */
 240
 241 static sdb_type_t sdb_plugin_cb_type = {
 242         sizeof(sdb_plugin_cb_t),
 243
 244         sdb_plugin_cb_init,
 245         sdb_plugin_cb_destroy
 246 };
 247
 248 static sdb_type_t sdb_plugin_collector_cb_type = {
 249         sizeof(sdb_plugin_collector_cb_t),
 250
 251         sdb_plugin_cb_init,
 252         sdb_plugin_cb_destroy
 253 };
 254
 255 static int
 256 sdb_plugin_add_callback(sdb_llist_t **list, const char *type,
 257                 const char *name, void *callback, sdb_object_t *user_data)
 258 {
 259         sdb_object_t *obj;
 260
 261         if ((! name) || (! callback))
 262                 return -1;
 263
 264         assert(list);
 265
 266         if (! *list)
 267                 *list = sdb_llist_create();
 268         if (! *list)
 269                 return -1;
 270
 271         obj = sdb_object_create(name, sdb_plugin_cb_type,
 272                         list, type, callback, user_data);
 273         if (! obj)
 274                 return -1;
 275
 276         if (sdb_llist_append(*list, obj)) {
 277                 sdb_object_deref(obj);
 278                 return -1;
 279         }
 280
 281         /* pass control to the list */
 282         sdb_object_deref(obj);
 283
 284         sdb_log(SDB_LOG_INFO, "plugin: Registered %s callback '%s'.",
 285                         type, name);
 286         return 0;
 287 } /* sdb_plugin_add_callback */
 288
 289 /*
 290  * public API
 291  */
 292
 293 int
 294 sdb_plugin_load(const char *name)
 295 {
 296         char  real_name[strlen(name) > 0 ? strlen(name) : 1];
 297         const char *name_ptr;
 298         char *tmp;
 299
 300         char filename[1024];
 301
 302         lt_dlhandle lh;
 303
 304         int (*mod_init)(sdb_plugin_info_t *);
 305         sdb_plugin_info_t info = SDB_PLUGIN_INFO_INIT;
 306
 307         int status;
 308
 309         if ((! name) || (! *name))
 310                 return -1;
 311
 312         real_name[0] = '\0';
 313         name_ptr = name;
 314
 315         while ((tmp = strstr(name_ptr, "::"))) {
 316                 strncat(real_name, name_ptr, (size_t)(tmp - name_ptr));
 317                 strcat(real_name, "/");
 318                 name_ptr = tmp + strlen("::");
 319         }
 320         strcat(real_name, name_ptr);
 321
 322         snprintf(filename, sizeof(filename), "%s/%s.so",
 323                         PKGLIBDIR, real_name);
 324         filename[sizeof(filename) - 1] = '\0';
 325
 326         if (access(filename, R_OK)) {
 327                 char errbuf[1024];
 328                 sdb_log(SDB_LOG_ERR, "plugin: Failed to load plugin '%s' (%s): %s",
 329                                 name, filename, sdb_strerror(errno, errbuf, sizeof(errbuf)));
 330                 return -1;
 331         }
 332
 333         lt_dlinit();
 334         lt_dlerror();
 335
 336         lh = lt_dlopen(filename);
 337         if (! lh) {
 338                 sdb_log(SDB_LOG_ERR, "plugin: Failed to load plugin '%s': %s"
 339                                 "The most common cause for this problem are missing "
 340                                 "dependencies.\n", name, lt_dlerror());
 341                 return -1;
 342         }
 343
 344         mod_init = (int (*)(sdb_plugin_info_t *))lt_dlsym(lh, "sdb_module_init");
 345         if (! mod_init) {
 346                 sdb_log(SDB_LOG_ERR, "plugin: Failed to load plugin '%s': "
 347                                 "could not find symbol 'sdb_module_init'", name);
 348                 return -1;
 349         }
 350
 351         status = mod_init(&info);
 352         if (status) {
 353                 sdb_log(SDB_LOG_ERR, "plugin: Failed to initialize "
 354                                 "plugin '%s'", name);
 355                 sdb_plugin_info_clear(&info);
 356                 return -1;
 357         }
 358
 359         /* compare minor version */
 360         if ((info.version < 0)
 361                         || ((int)(info.version / 100) != (int)(SDB_VERSION / 100)))
 362                 sdb_log(SDB_LOG_WARNING, "plugin: WARNING: version of "
 363                                 "plugin '%s' (%i.%i.%i) does not match our version "
 364                                 "(%i.%i.%i); this might cause problems",
 365                                 name, SDB_VERSION_DECODE(info.version),
 366                                 SDB_VERSION_DECODE(SDB_VERSION));
 367
 368         sdb_log(SDB_LOG_INFO, "plugin: Successfully loaded "
 369                         "plugin '%s' v%i (%s)\n\t%s\n\tLicense: %s",
 370                         INFO_GET(&info, name), info.plugin_version,
 371                         INFO_GET(&info, description),
 372                         INFO_GET(&info, copyright),
 373                         INFO_GET(&info, license));
 374         sdb_plugin_info_clear(&info);
 375         return 0;
 376 } /* sdb_plugin_load */
 377
 378 int
 379 sdb_plugin_set_info(sdb_plugin_info_t *info, int type, ...)
 380 {
 381         va_list ap;
 382
 383         if (! info)
 384                 return -1;
 385
 386         va_start(ap, type);
 387
 388         switch (type) {
 389                 case SDB_PLUGIN_INFO_NAME:
 390                         {
 391                                 char *name = va_arg(ap, char *);
 392                                 if (name) {
 393                                         if (info->name)
 394                                                 free(info->name);
 395                                         info->name = strdup(name);
 396                                 }
 397                         }
 398                         break;
 399                 case SDB_PLUGIN_INFO_DESC:
 400                         {
 401                                 char *desc = va_arg(ap, char *);
 402                                 if (desc) {
 403                                         if (info->description)
 404                                                 free(info->description);
 405                                         info->description = strdup(desc);
 406                                 }
 407                         }
 408                         break;
 409                 case SDB_PLUGIN_INFO_COPYRIGHT:
 410                         {
 411                                 char *copyright = va_arg(ap, char *);
 412                                 if (copyright)
 413                                         info->copyright = strdup(copyright);
 414                         }
 415                         break;
 416                 case SDB_PLUGIN_INFO_LICENSE:
 417                         {
 418                                 char *license = va_arg(ap, char *);
 419                                 if (license) {
 420                                         if (info->license)
 421                                                 free(info->license);
 422                                         info->license = strdup(license);
 423                                 }
 424                         }
 425                         break;
 426                 case SDB_PLUGIN_INFO_VERSION:
 427                         {
 428                                 int version = va_arg(ap, int);
 429                                 info->version = version;
 430                         }
 431                         break;
 432                 case SDB_PLUGIN_INFO_PLUGIN_VERSION:
 433                         {
 434                                 int version = va_arg(ap, int);
 435                                 info->plugin_version = version;
 436                         }
 437                         break;
 438                 default:
 439                         va_end(ap);
 440                         return -1;
 441         }
 442
 443         va_end(ap);
 444         return 0;
 445 } /* sdb_plugin_set_info */
 446
 447 int
 448 sdb_plugin_register_config(const char *name, sdb_plugin_config_cb callback)
 449 {
 450         return sdb_plugin_add_callback(&config_list, "init", name,
 451                         callback, NULL);
 452 } /* sdb_plugin_register_config */
 453
 454 int
 455 sdb_plugin_register_init(const char *name, sdb_plugin_init_cb callback,
 456                 sdb_object_t *user_data)
 457 {
 458         return sdb_plugin_add_callback(&init_list, "init", name,
 459                         callback, user_data);
 460 } /* sdb_plugin_register_init */
 461
 462 int
 463 sdb_plugin_register_shutdown(const char *name, sdb_plugin_shutdown_cb callback,
 464                 sdb_object_t *user_data)
 465 {
 466         return sdb_plugin_add_callback(&shutdown_list, "shutdown", name,
 467                         callback, user_data);
 468 } /* sdb_plugin_register_shutdown */
 469
 470 int
 471 sdb_plugin_register_log(const char *name, sdb_plugin_log_cb callback,
 472                 sdb_object_t *user_data)
 473 {
 474         return sdb_plugin_add_callback(&log_list, "log", name, callback,
 475                         user_data);
 476 } /* sdb_plugin_register_log */
 477
 478 int
 479 sdb_plugin_register_cname(const char *name, sdb_plugin_cname_cb callback,
 480                 sdb_object_t *user_data)
 481 {
 482         return sdb_plugin_add_callback(&cname_list, "cname", name, callback,
 483                         user_data);
 484 } /* sdb_plugin_register_cname */
 485
 486 int
 487 sdb_plugin_register_collector(const char *name, sdb_plugin_collector_cb callback,
 488                 const sdb_time_t *interval, sdb_object_t *user_data)
 489 {
 490         sdb_object_t *obj;
 491
 492         if ((! name) || (! callback))
 493                 return -1;
 494
 495         if (! collector_list)
 496                 collector_list = sdb_llist_create();
 497         if (! collector_list)
 498                 return -1;
 499
 500         obj = sdb_object_create(name, sdb_plugin_collector_cb_type,
 501                         &collector_list, "collector", callback, user_data);
 502         if (! obj)
 503                 return -1;
 504
 505         if (interval)
 506                 SDB_PLUGIN_CCB(obj)->ccb_interval = *interval;
 507         else {
 508                 sdb_time_t tmp = sdb_plugin_get_ctx().interval;
 509
 510                 if (tmp > 0)
 511                         SDB_PLUGIN_CCB(obj)->ccb_interval = tmp;
 512                 else
 513                         SDB_PLUGIN_CCB(obj)->ccb_interval = 0;
 514         }
 515
 516         if (! (SDB_PLUGIN_CCB(obj)->ccb_next_update = sdb_gettime())) {
 517                 char errbuf[1024];
 518                 sdb_log(SDB_LOG_ERR, "plugin: Failed to determine current "
 519                                 "time: %s", sdb_strerror(errno, errbuf, sizeof(errbuf)));
 520                 sdb_object_deref(obj);
 521                 return -1;
 522         }
 523
 524         if (sdb_llist_insert_sorted(collector_list, obj,
 525                                 sdb_plugin_cmp_next_update)) {
 526                 sdb_object_deref(obj);
 527                 return -1;
 528         }
 529
 530         /* pass control to the list */
 531         sdb_object_deref(obj);
 532
 533         sdb_log(SDB_LOG_INFO, "plugin: Registered collector callback '%s' "
 534                         "(interval = %.3fs).", name,
 535                         SDB_TIME_TO_DOUBLE(SDB_PLUGIN_CCB(obj)->ccb_interval));
 536         return 0;
 537 } /* sdb_plugin_register_collector */
 538
 539 sdb_plugin_ctx_t
 540 sdb_plugin_get_ctx(void)
 541 {
 542         ctx_t *ctx;
 543
 544         if (! plugin_ctx_key_initialized)
 545                 ctx_key_init();
 546         ctx = pthread_getspecific(plugin_ctx_key);
 547
 548         if (! ctx)
 549                 ctx = ctx_create();
 550         if (! ctx)
 551                 return plugin_default_ctx;
 552         return ctx->public;
 553 } /* sdb_plugin_get_ctx */
 554
 555 sdb_plugin_ctx_t
 556 sdb_plugin_set_ctx(sdb_plugin_ctx_t ctx)
 557 {
 558         ctx_t *tmp;
 559         sdb_plugin_ctx_t old;
 560
 561         if (! plugin_ctx_key_initialized)
 562                 ctx_key_init();
 563         tmp = pthread_getspecific(plugin_ctx_key);
 564
 565         if (! tmp)
 566                 tmp = ctx_create();
 567         if (! tmp)
 568                 return plugin_default_ctx;
 569
 570         old = tmp->public;
 571         tmp->public = ctx;
 572         return old;
 573 } /* sdb_plugin_set_ctx */
 574
 575 int
 576 sdb_plugin_configure(const char *name, oconfig_item_t *ci)
 577 {
 578         sdb_plugin_cb_t *plugin;
 579         sdb_plugin_config_cb callback;
 580
 581         sdb_plugin_ctx_t old_ctx;
 582
 583         int status;
 584
 585         if ((! name) || (! ci))
 586                 return -1;
 587
 588         plugin = SDB_PLUGIN_CB(sdb_llist_search_by_name(config_list, name));
 589         if (! plugin) {
 590                 /* XXX: check if any such plugin has been loaded */
 591                 sdb_log(SDB_LOG_ERR, "plugin: Plugin '%s' did not register "
 592                                 "a config callback.", name);
 593                 errno = ENOENT;
 594                 return -1;
 595         }
 596
 597         old_ctx = sdb_plugin_set_ctx(plugin->cb_ctx);
 598         callback = plugin->cb_callback;
 599         status = callback(ci);
 600         sdb_plugin_set_ctx(old_ctx);
 601         return status;
 602 } /* sdb_plugin_configure */
 603
 604 int
 605 sdb_plugin_init_all(void)
 606 {
 607         sdb_llist_iter_t *iter;
 608
 609         iter = sdb_llist_get_iter(init_list);
 610         while (sdb_llist_iter_has_next(iter)) {
 611                 sdb_plugin_init_cb callback;
 612                 sdb_plugin_ctx_t old_ctx;
 613
 614                 sdb_object_t *obj = sdb_llist_iter_get_next(iter);
 615                 assert(obj);
 616
 617                 callback = SDB_PLUGIN_CB(obj)->cb_callback;
 618
 619                 old_ctx = sdb_plugin_set_ctx(SDB_PLUGIN_CB(obj)->cb_ctx);
 620                 if (callback(SDB_PLUGIN_CB(obj)->cb_user_data)) {
 621                         /* XXX: unload plugin */
 622                 }
 623                 sdb_plugin_set_ctx(old_ctx);
 624         }
 625         sdb_llist_iter_destroy(iter);
 626         return 0;
 627 } /* sdb_plugin_init_all */
 628
 629 int
 630 sdb_plugin_collector_loop(sdb_plugin_loop_t *loop)
 631 {
 632         if (! collector_list) {
 633                 sdb_log(SDB_LOG_WARNING, "plugin: No collectors registered. "
 634                                 "Quiting main loop.");
 635                 return -1;
 636         }
 637
 638         if (! loop)
 639                 return -1;
 640
 641         while (loop->do_loop) {
 642                 sdb_plugin_collector_cb callback;
 643                 sdb_plugin_ctx_t old_ctx;
 644
 645                 sdb_time_t interval, now;
 646
 647                 sdb_object_t *obj = sdb_llist_shift(collector_list);
 648                 if (! obj)
 649                         return -1;
 650
 651                 callback = SDB_PLUGIN_CCB(obj)->ccb_callback;
 652
 653                 if (! (now = sdb_gettime())) {
 654                         char errbuf[1024];
 655                         sdb_log(SDB_LOG_ERR, "plugin: Failed to determine current "
 656                                         "time: %s", sdb_strerror(errno, errbuf, sizeof(errbuf)));
 657                         now = SDB_PLUGIN_CCB(obj)->ccb_next_update;
 658                 }
 659
 660                 if (now < SDB_PLUGIN_CCB(obj)->ccb_next_update) {
 661                         interval = SDB_PLUGIN_CCB(obj)->ccb_next_update - now;
 662
 663                         errno = 0;
 664                         while (loop->do_loop && sdb_sleep(interval, &interval)) {
 665                                 if (errno != EINTR) {
 666                                         char errbuf[1024];
 667                                         sdb_log(SDB_LOG_ERR, "plugin: Failed to sleep: %s",
 668                                                         sdb_strerror(errno, errbuf, sizeof(errbuf)));
 669                                         return -1;
 670                                 }
 671                                 errno = 0;
 672                         }
 673
 674                         if (! loop->do_loop)
 675                                 return 0;
 676                 }
 677
 678                 old_ctx = sdb_plugin_set_ctx(SDB_PLUGIN_CCB(obj)->ccb_ctx);
 679                 if (callback(SDB_PLUGIN_CCB(obj)->ccb_user_data)) {
 680                         /* XXX */
 681                 }
 682                 sdb_plugin_set_ctx(old_ctx);
 683
 684                 interval = SDB_PLUGIN_CCB(obj)->ccb_interval;
 685                 if (! interval)
 686                         interval = loop->default_interval;
 687                 if (! interval) {
 688                         sdb_log(SDB_LOG_WARNING, "plugin: No interval configured "
 689                                         "for plugin '%s'; skipping any further "
 690                                         "iterations.", obj->name);
 691                         sdb_object_deref(obj);
 692                         continue;
 693                 }
 694
 695                 SDB_PLUGIN_CCB(obj)->ccb_next_update += interval;
 696
 697                 if (! (now = sdb_gettime())) {
 698                         char errbuf[1024];
 699                         sdb_log(SDB_LOG_ERR, "plugin: Failed to determine current "
 700                                         "time: %s", sdb_strerror(errno, errbuf, sizeof(errbuf)));
 701                         now = SDB_PLUGIN_CCB(obj)->ccb_next_update;
 702                 }
 703
 704                 if (now > SDB_PLUGIN_CCB(obj)->ccb_next_update) {
 705                         sdb_log(SDB_LOG_WARNING, "plugin: Plugin '%s' took too "
 706                                         "long; skipping iterations to keep up.",
 707                                         obj->name);
 708                         SDB_PLUGIN_CCB(obj)->ccb_next_update = now;
 709                 }
 710
 711                 if (sdb_llist_insert_sorted(collector_list, obj,
 712                                         sdb_plugin_cmp_next_update)) {
 713                         sdb_log(SDB_LOG_ERR, "plugin: Failed to re-insert "
 714                                         "plugin '%s' into collector list. Unable to further "
 715                                         "use the plugin.",
 716                                         obj->name);
 717                         sdb_object_deref(obj);
 718                         return -1;
 719                 }
 720
 721                 /* pass control back to the list */
 722                 sdb_object_deref(obj);
 723         }
 724         return 0;
 725 } /* sdb_plugin_read_loop */
 726
 727 char *
 728 sdb_plugin_cname(char *hostname)
 729 {
 730         sdb_llist_iter_t *iter;
 731
 732         if (! hostname)
 733                 return NULL;
 734
 735         if (! cname_list)
 736                 return hostname;
 737
 738         iter = sdb_llist_get_iter(cname_list);
 739         while (sdb_llist_iter_has_next(iter)) {
 740                 sdb_plugin_cname_cb callback;
 741                 char *cname;
 742
 743                 sdb_object_t *obj = sdb_llist_iter_get_next(iter);
 744                 assert(obj);
 745
 746                 callback = SDB_PLUGIN_CB(obj)->cb_callback;
 747                 cname = callback(hostname, SDB_PLUGIN_CB(obj)->cb_user_data);
 748                 if (cname) {
 749                         free(hostname);
 750                         hostname = cname;
 751                 }
 752                 /* else: don't change hostname */
 753         }
 754         sdb_llist_iter_destroy(iter);
 755         return hostname;
 756 } /* sdb_plugin_cname */
 757
 758 int
 759 sdb_plugin_log(int prio, const char *msg)
 760 {
 761         sdb_llist_iter_t *iter;
 762         int ret = -1;
 763
 764         if (! msg)
 765                 return 0;
 766
 767         if (! log_list)
 768                 return fprintf(stderr, "[%s] %s\n", SDB_LOG_PRIO_TO_STRING(prio), msg);
 769
 770         iter = sdb_llist_get_iter(log_list);
 771         while (sdb_llist_iter_has_next(iter)) {
 772                 sdb_plugin_log_cb callback;
 773                 int tmp;
 774
 775                 sdb_object_t *obj = sdb_llist_iter_get_next(iter);
 776                 assert(obj);
 777
 778                 callback = SDB_PLUGIN_CB(obj)->cb_callback;
 779                 tmp = callback(prio, msg, SDB_PLUGIN_CB(obj)->cb_user_data);
 780                 if (tmp > ret)
 781                         ret = tmp;
 782         }
 783         sdb_llist_iter_destroy(iter);
 784         return ret;
 785 } /* sdb_plugin_log */
 786
 787 int
 788 sdb_plugin_vlogf(int prio, const char *fmt, va_list ap)
 789 {
 790         sdb_strbuf_t *buf;
 791         int ret;
 792
 793         if (! fmt)
 794                 return 0;
 795
 796         buf = sdb_strbuf_create(64);
 797         if (! buf) {
 798                 ret = fprintf(stderr, "[%s] ", SDB_LOG_PRIO_TO_STRING(prio));
 799                 ret += vfprintf(stderr, fmt, ap);
 800                 return ret;
 801         }
 802
 803         if (sdb_strbuf_vsprintf(buf, fmt, ap) < 0) {
 804                 sdb_strbuf_destroy(buf);
 805                 return -1;
 806         }
 807
 808         ret = sdb_plugin_log(prio, sdb_strbuf_string(buf));
 809         sdb_strbuf_destroy(buf);
 810         return ret;
 811 } /* sdb_plugin_vlogf */
 812
 813 int
 814 sdb_plugin_logf(int prio, const char *fmt, ...)
 815 {
 816         va_list ap;
 817         int ret;
 818
 819         if (! fmt)
 820                 return 0;
 821
 822         va_start(ap, fmt);
 823         ret = sdb_plugin_vlogf(prio, fmt, ap);
 824         va_end(ap);
 825         return ret;
 826 } /* sdb_plugin_logf */
 827
 828 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 829