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 #if HAVE_CONFIG_H
  29 #       include "config.h"
  30 #endif /* HAVE_CONFIG_H */
  31
  32 #include "sysdb.h"
  33 #include "core/plugin.h"
  34 #include "core/time.h"
  35 #include "utils/error.h"
  36 #include "utils/llist.h"
  37 #include "utils/strbuf.h"
  38
  39 #include <assert.h>
  40
  41 #include <errno.h>
  42
  43 #include <stdarg.h>
  44 #include <stdio.h>
  45 #include <string.h>
  46 #include <strings.h>
  47 #include <unistd.h>
  48
  49 #include <ltdl.h>
  50
  51 #include <pthread.h>
  52
  53 /*
  54  * private data types
  55  */
  56
  57 struct sdb_plugin_info {
  58         char *plugin_name;
  59         char *filename;
  60
  61         /* public attributes */
  62         char *name;
  63
  64         char *description;
  65         char *copyright;
  66         char *license;
  67
  68         int   version;
  69         int   plugin_version;
  70 };
  71 #define SDB_PLUGIN_INFO_INIT { \
  72         /* plugin_name */ NULL, /* filename */ NULL, \
  73         /* name */ NULL, /* desc */ NULL, \
  74         /* copyright */ NULL, /* license */ NULL, \
  75         /* version */ -1, /* plugin_version */ -1 }
  76 #define INFO_GET(i, attr) \
  77         ((i)->attr ? (i)->attr : #attr" not set")
  78
  79 typedef struct {
  80         sdb_object_t super;
  81         sdb_plugin_ctx_t public;
  82
  83         sdb_plugin_info_t info;
  84
  85         /* The usage count differs from the object's ref count
  86          * in that it provides higher level information about how
  87          * the plugin is in use. */
  88         size_t use_cnt;
  89 } ctx_t;
  90 #define CTX_INIT { SDB_OBJECT_INIT, \
  91         SDB_PLUGIN_CTX_INIT, SDB_PLUGIN_INFO_INIT, 0 }
  92
  93 #define CTX(obj) ((ctx_t *)(obj))
  94
  95 typedef struct {
  96         sdb_object_t super;
  97         void *cb_callback;
  98         sdb_object_t *cb_user_data;
  99         ctx_t *cb_ctx;
 100 } sdb_plugin_cb_t;
 101 #define SDB_PLUGIN_CB_INIT { SDB_OBJECT_INIT, \
 102         /* callback = */ NULL, /* user_data = */ NULL, \
 103         SDB_PLUGIN_CTX_INIT }
 104
 105 typedef struct {
 106         sdb_plugin_cb_t super;
 107 #define ccb_callback super.cb_callback
 108 #define ccb_user_data super.cb_user_data
 109 #define ccb_ctx super.cb_ctx
 110         sdb_time_t ccb_interval;
 111         sdb_time_t ccb_next_update;
 112 } sdb_plugin_collector_cb_t;
 113
 114 #define SDB_PLUGIN_CB(obj) ((sdb_plugin_cb_t *)(obj))
 115 #define SDB_CONST_PLUGIN_CB(obj) ((const sdb_plugin_cb_t *)(obj))
 116 #define SDB_PLUGIN_CCB(obj) ((sdb_plugin_collector_cb_t *)(obj))
 117 #define SDB_CONST_PLUGIN_CCB(obj) ((const sdb_plugin_collector_cb_t *)(obj))
 118
 119 /*
 120  * private variables
 121  */
 122
 123 static sdb_plugin_ctx_t  plugin_default_ctx  = SDB_PLUGIN_CTX_INIT;
 124 static sdb_plugin_info_t plugin_default_info = SDB_PLUGIN_INFO_INIT;
 125
 126 static pthread_key_t     plugin_ctx_key;
 127 static _Bool             plugin_ctx_key_initialized = 0;
 128
 129 /* a list of the plugin contexts of all registered plugins */
 130 static sdb_llist_t      *all_plugins = NULL;
 131
 132 static sdb_llist_t      *config_list = NULL;
 133 static sdb_llist_t      *init_list = NULL;
 134 static sdb_llist_t      *collector_list = NULL;
 135 static sdb_llist_t      *cname_list = NULL;
 136 static sdb_llist_t      *shutdown_list = NULL;
 137 static sdb_llist_t      *log_list = NULL;
 138
 139 /*
 140  * private helper functions
 141  */
 142
 143 static void
 144 plugin_info_clear(sdb_plugin_info_t *info)
 145 {
 146         sdb_plugin_info_t empty_info = SDB_PLUGIN_INFO_INIT;
 147         if (! info)
 148                 return;
 149
 150         if (info->plugin_name)
 151                 free(info->plugin_name);
 152         if (info->filename)
 153                 free(info->filename);
 154
 155         if (info->name)
 156                 free(info->name);
 157         if (info->description)
 158                 free(info->description);
 159         if (info->copyright)
 160                 free(info->copyright);
 161         if (info->license)
 162                 free(info->license);
 163
 164         *info = empty_info;
 165 } /* plugin_info_clear */
 166
 167 static void
 168 ctx_key_init(void)
 169 {
 170         if (plugin_ctx_key_initialized)
 171                 return;
 172
 173         pthread_key_create(&plugin_ctx_key, /* destructor */ NULL);
 174         plugin_ctx_key_initialized = 1;
 175 } /* ctx_key_init */
 176
 177 static int
 178 plugin_cmp_next_update(const sdb_object_t *a, const sdb_object_t *b)
 179 {
 180         const sdb_plugin_collector_cb_t *ccb1
 181                 = (const sdb_plugin_collector_cb_t *)a;
 182         const sdb_plugin_collector_cb_t *ccb2
 183                 = (const sdb_plugin_collector_cb_t *)b;
 184
 185         assert(ccb1 && ccb2);
 186
 187         return (ccb1->ccb_next_update > ccb2->ccb_next_update)
 188                 ? 1 : (ccb1->ccb_next_update < ccb2->ccb_next_update)
 189                 ? -1 : 0;
 190 } /* plugin_cmp_next_update */
 191
 192 static int
 193 plugin_lookup_by_name(const sdb_object_t *obj, const void *id)
 194 {
 195         const sdb_plugin_cb_t *cb = SDB_CONST_PLUGIN_CB(obj);
 196         const char *name = id;
 197
 198         assert(cb && id && cb->cb_ctx);
 199         if (!strcasecmp(cb->cb_ctx->info.plugin_name, name))
 200                 return 0;
 201         return 1;
 202 } /* plugin_lookup_by_name */
 203
 204 static void
 205 plugin_unregister_by_name(const char *plugin_name)
 206 {
 207         size_t i;
 208
 209         struct {
 210                 const char  *type;
 211                 sdb_llist_t *list;
 212         } all_lists[] = {
 213                 { "config",    config_list },
 214                 { "init",      init_list },
 215                 { "collector", collector_list },
 216                 { "cname",     cname_list },
 217                 { "shutdown",  shutdown_list },
 218                 { "log",       log_list },
 219         };
 220
 221         for (i = 0; i < SDB_STATIC_ARRAY_LEN(all_lists); ++i) {
 222                 const char  *type = all_lists[i].type;
 223                 sdb_llist_t *list = all_lists[i].list;
 224
 225                 while (1) {
 226                         sdb_object_t *obj = sdb_llist_remove(list,
 227                                         plugin_lookup_by_name, plugin_name);
 228                         sdb_plugin_cb_t *cb = SDB_PLUGIN_CB(obj);
 229
 230                         if (! obj)
 231                                 break;
 232
 233                         sdb_log(SDB_LOG_INFO, "core: Unregistering "
 234                                         "%s callback '%s' (module %s)", type, obj->name,
 235                                         cb->cb_ctx->info.plugin_name);
 236                         sdb_object_deref(obj);
 237                 }
 238         }
 239 } /* plugin_unregister_by_name */
 240
 241 /*
 242  * private types
 243  */
 244
 245 static int
 246 ctx_init(sdb_object_t *obj, va_list __attribute__((unused)) ap)
 247 {
 248         ctx_t *ctx = CTX(obj);
 249
 250         assert(ctx);
 251
 252         ctx->public = plugin_default_ctx;
 253         ctx->info = plugin_default_info;
 254         ctx->use_cnt = 1;
 255         return 0;
 256 } /* ctx_init */
 257
 258 static void
 259 ctx_destroy(sdb_object_t *obj)
 260 {
 261         ctx_t *ctx = CTX(obj);
 262         plugin_info_clear(&ctx->info);
 263 } /* ctx_destroy */
 264
 265 static sdb_type_t ctx_type = {
 266         sizeof(ctx_t),
 267
 268         ctx_init,
 269         ctx_destroy
 270 };
 271
 272 static ctx_t *
 273 ctx_create(const char *name)
 274 {
 275         ctx_t *ctx;
 276
 277         ctx = CTX(sdb_object_create(name, ctx_type));
 278         if (! ctx)
 279                 return NULL;
 280
 281         if (! plugin_ctx_key_initialized)
 282                 ctx_key_init();
 283         pthread_setspecific(plugin_ctx_key, ctx);
 284         return ctx;
 285 } /* ctx_create */
 286
 287 static ctx_t *
 288 ctx_get(void)
 289 {
 290         if (! plugin_ctx_key_initialized)
 291                 ctx_key_init();
 292         return pthread_getspecific(plugin_ctx_key);
 293 } /* ctx_get */
 294
 295 static ctx_t *
 296 ctx_set(ctx_t *new)
 297 {
 298         ctx_t *old;
 299
 300         if (! plugin_ctx_key_initialized)
 301                 ctx_key_init();
 302
 303         old = pthread_getspecific(plugin_ctx_key);
 304         pthread_setspecific(plugin_ctx_key, new);
 305         return old;
 306 } /* ctx_set */
 307
 308 static int
 309 plugin_cb_init(sdb_object_t *obj, va_list ap)
 310 {
 311         sdb_llist_t **list = va_arg(ap, sdb_llist_t **);
 312         const char   *type = va_arg(ap, const char *);
 313         void     *callback = va_arg(ap, void *);
 314         sdb_object_t   *ud = va_arg(ap, sdb_object_t *);
 315
 316         assert(list);
 317         assert(type);
 318         assert(obj);
 319
 320         if (sdb_llist_search_by_name(*list, obj->name)) {
 321                 sdb_log(SDB_LOG_WARNING, "core: %s callback '%s' "
 322                                 "has already been registered. Ignoring newly "
 323                                 "registered version.", type, obj->name);
 324                 return -1;
 325         }
 326
 327         SDB_PLUGIN_CB(obj)->cb_callback = callback;
 328         SDB_PLUGIN_CB(obj)->cb_ctx      = ctx_get();
 329         sdb_object_ref(SDB_OBJ(SDB_PLUGIN_CB(obj)->cb_ctx));
 330
 331         sdb_object_ref(ud);
 332         SDB_PLUGIN_CB(obj)->cb_user_data = ud;
 333         return 0;
 334 } /* plugin_cb_init */
 335
 336 static void
 337 plugin_cb_destroy(sdb_object_t *obj)
 338 {
 339         assert(obj);
 340         sdb_object_deref(SDB_PLUGIN_CB(obj)->cb_user_data);
 341         sdb_object_deref(SDB_OBJ(SDB_PLUGIN_CB(obj)->cb_ctx));
 342 } /* plugin_cb_destroy */
 343
 344 static sdb_type_t sdb_plugin_cb_type = {
 345         sizeof(sdb_plugin_cb_t),
 346
 347         plugin_cb_init,
 348         plugin_cb_destroy
 349 };
 350
 351 static sdb_type_t sdb_plugin_collector_cb_type = {
 352         sizeof(sdb_plugin_collector_cb_t),
 353
 354         plugin_cb_init,
 355         plugin_cb_destroy
 356 };
 357
 358 static int
 359 plugin_add_callback(sdb_llist_t **list, const char *type,
 360                 const char *name, void *callback, sdb_object_t *user_data)
 361 {
 362         sdb_object_t *obj;
 363
 364         if ((! name) || (! callback))
 365                 return -1;
 366
 367         assert(list);
 368
 369         if (! *list)
 370                 *list = sdb_llist_create();
 371         if (! *list)
 372                 return -1;
 373
 374         obj = sdb_object_create(name, sdb_plugin_cb_type,
 375                         list, type, callback, user_data);
 376         if (! obj)
 377                 return -1;
 378
 379         if (sdb_llist_append(*list, obj)) {
 380                 sdb_object_deref(obj);
 381                 return -1;
 382         }
 383
 384         /* pass control to the list */
 385         sdb_object_deref(obj);
 386
 387         sdb_log(SDB_LOG_INFO, "core: Registered %s callback '%s'.",
 388                         type, name);
 389         return 0;
 390 } /* plugin_add_callback */
 391
 392 /*
 393  * public API
 394  */
 395
 396 int
 397 sdb_plugin_load(const char *name, const sdb_plugin_ctx_t *plugin_ctx)
 398 {
 399         char  base_name[name ? strlen(name) + 1 : 1];
 400         const char *name_ptr;
 401         char *tmp;
 402
 403         char filename[1024];
 404         ctx_t *ctx;
 405
 406         lt_dlhandle lh;
 407
 408         int (*mod_init)(sdb_plugin_info_t *);
 409         int status;
 410
 411         if ((! name) || (! *name))
 412                 return -1;
 413
 414         base_name[0] = '\0';
 415         name_ptr = name;
 416
 417         while ((tmp = strstr(name_ptr, "::"))) {
 418                 strncat(base_name, name_ptr, (size_t)(tmp - name_ptr));
 419                 strcat(base_name, "/");
 420                 name_ptr = tmp + strlen("::");
 421         }
 422         strcat(base_name, name_ptr);
 423
 424         ctx = CTX(sdb_llist_search_by_name(all_plugins, base_name));
 425         if (ctx) {
 426                 /* plugin already loaded */
 427                 ++ctx->use_cnt;
 428                 return 0;
 429         }
 430
 431         snprintf(filename, sizeof(filename), "%s/%s.so",
 432                         PKGLIBDIR, base_name);
 433         filename[sizeof(filename) - 1] = '\0';
 434
 435         if (access(filename, R_OK)) {
 436                 char errbuf[1024];
 437                 sdb_log(SDB_LOG_ERR, "core: Failed to load plugin '%s' (%s): %s",
 438                                 name, filename, sdb_strerror(errno, errbuf, sizeof(errbuf)));
 439                 return -1;
 440         }
 441
 442         lt_dlinit();
 443         lt_dlerror();
 444
 445         lh = lt_dlopen(filename);
 446         if (! lh) {
 447                 sdb_log(SDB_LOG_ERR, "core: Failed to load plugin '%s': %s"
 448                                 "The most common cause for this problem are missing "
 449                                 "dependencies.\n", name, lt_dlerror());
 450                 return -1;
 451         }
 452
 453         if (ctx_get())
 454                 sdb_log(SDB_LOG_WARNING, "core: Discarding old plugin context");
 455
 456         ctx = ctx_create(name);
 457         if (! ctx) {
 458                 sdb_log(SDB_LOG_ERR, "core: Failed to initialize plugin context");
 459                 return -1;
 460         }
 461
 462         ctx->info.plugin_name = strdup(name);
 463         ctx->info.filename = strdup(filename);
 464
 465         if (plugin_ctx)
 466                 ctx->public = *plugin_ctx;
 467
 468         mod_init = (int (*)(sdb_plugin_info_t *))lt_dlsym(lh, "sdb_module_init");
 469         if (! mod_init) {
 470                 sdb_log(SDB_LOG_ERR, "core: Failed to load plugin '%s': "
 471                                 "could not find symbol 'sdb_module_init'", name);
 472                 sdb_object_deref(SDB_OBJ(ctx));
 473                 return -1;
 474         }
 475
 476         status = mod_init(&ctx->info);
 477         if (status) {
 478                 sdb_log(SDB_LOG_ERR, "core: Failed to initialize "
 479                                 "module '%s'", name);
 480                 plugin_unregister_by_name(ctx->info.plugin_name);
 481                 sdb_object_deref(SDB_OBJ(ctx));
 482                 return -1;
 483         }
 484
 485         /* compare minor version */
 486         if ((ctx->info.version < 0)
 487                         || ((int)(ctx->info.version / 100) != (int)(SDB_VERSION / 100)))
 488                 sdb_log(SDB_LOG_WARNING, "core: WARNING: version of "
 489                                 "plugin '%s' (%i.%i.%i) does not match our version "
 490                                 "(%i.%i.%i); this might cause problems",
 491                                 name, SDB_VERSION_DECODE(ctx->info.version),
 492                                 SDB_VERSION_DECODE(SDB_VERSION));
 493
 494         if (! all_plugins) {
 495                 if (! (all_plugins = sdb_llist_create())) {
 496                         sdb_log(SDB_LOG_ERR, "core: Failed to load plugin '%s': "
 497                                         "internal error while creating linked list", name);
 498                         plugin_unregister_by_name(ctx->info.plugin_name);
 499                         sdb_object_deref(SDB_OBJ(ctx));
 500                         return -1;
 501                 }
 502         }
 503
 504         sdb_llist_append(all_plugins, SDB_OBJ(ctx));
 505
 506         sdb_log(SDB_LOG_INFO, "core: Successfully loaded "
 507                         "plugin '%s' v%i (%s)\n\t%s\n\tLicense: %s",
 508                         INFO_GET(&ctx->info, name), ctx->info.plugin_version,
 509                         INFO_GET(&ctx->info, description),
 510                         INFO_GET(&ctx->info, copyright),
 511                         INFO_GET(&ctx->info, license));
 512
 513         /* any registered callbacks took ownership of the context */
 514         sdb_object_deref(SDB_OBJ(ctx));
 515
 516         /* reset */
 517         ctx_set(NULL);
 518         return 0;
 519 } /* sdb_plugin_load */
 520
 521 int
 522 sdb_plugin_set_info(sdb_plugin_info_t *info, int type, ...)
 523 {
 524         va_list ap;
 525
 526         if (! info)
 527                 return -1;
 528
 529         va_start(ap, type);
 530
 531         switch (type) {
 532                 case SDB_PLUGIN_INFO_NAME:
 533                         {
 534                                 char *name = va_arg(ap, char *);
 535                                 if (name) {
 536                                         if (info->name)
 537                                                 free(info->name);
 538                                         info->name = strdup(name);
 539                                 }
 540                         }
 541                         break;
 542                 case SDB_PLUGIN_INFO_DESC:
 543                         {
 544                                 char *desc = va_arg(ap, char *);
 545                                 if (desc) {
 546                                         if (info->description)
 547                                                 free(info->description);
 548                                         info->description = strdup(desc);
 549                                 }
 550                         }
 551                         break;
 552                 case SDB_PLUGIN_INFO_COPYRIGHT:
 553                         {
 554                                 char *copyright = va_arg(ap, char *);
 555                                 if (copyright)
 556                                         info->copyright = strdup(copyright);
 557                         }
 558                         break;
 559                 case SDB_PLUGIN_INFO_LICENSE:
 560                         {
 561                                 char *license = va_arg(ap, char *);
 562                                 if (license) {
 563                                         if (info->license)
 564                                                 free(info->license);
 565                                         info->license = strdup(license);
 566                                 }
 567                         }
 568                         break;
 569                 case SDB_PLUGIN_INFO_VERSION:
 570                         {
 571                                 int version = va_arg(ap, int);
 572                                 info->version = version;
 573                         }
 574                         break;
 575                 case SDB_PLUGIN_INFO_PLUGIN_VERSION:
 576                         {
 577                                 int version = va_arg(ap, int);
 578                                 info->plugin_version = version;
 579                         }
 580                         break;
 581                 default:
 582                         va_end(ap);
 583                         return -1;
 584         }
 585
 586         va_end(ap);
 587         return 0;
 588 } /* sdb_plugin_set_info */
 589
 590 int
 591 sdb_plugin_register_config(const char *name, sdb_plugin_config_cb callback)
 592 {
 593         return plugin_add_callback(&config_list, "init", name,
 594                         (void *)callback, NULL);
 595 } /* sdb_plugin_register_config */
 596
 597 int
 598 sdb_plugin_register_init(const char *name, sdb_plugin_init_cb callback,
 599                 sdb_object_t *user_data)
 600 {
 601         return plugin_add_callback(&init_list, "init", name,
 602                         (void *)callback, user_data);
 603 } /* sdb_plugin_register_init */
 604
 605 int
 606 sdb_plugin_register_shutdown(const char *name, sdb_plugin_shutdown_cb callback,
 607                 sdb_object_t *user_data)
 608 {
 609         return plugin_add_callback(&shutdown_list, "shutdown", name,
 610                         (void *)callback, user_data);
 611 } /* sdb_plugin_register_shutdown */
 612
 613 int
 614 sdb_plugin_register_log(const char *name, sdb_plugin_log_cb callback,
 615                 sdb_object_t *user_data)
 616 {
 617         return plugin_add_callback(&log_list, "log", name, (void *)callback,
 618                         user_data);
 619 } /* sdb_plugin_register_log */
 620
 621 int
 622 sdb_plugin_register_cname(const char *name, sdb_plugin_cname_cb callback,
 623                 sdb_object_t *user_data)
 624 {
 625         return plugin_add_callback(&cname_list, "cname", name, (void *)callback,
 626                         user_data);
 627 } /* sdb_plugin_register_cname */
 628
 629 int
 630 sdb_plugin_register_collector(const char *name, sdb_plugin_collector_cb callback,
 631                 const sdb_time_t *interval, sdb_object_t *user_data)
 632 {
 633         sdb_object_t *obj;
 634
 635         if ((! name) || (! callback))
 636                 return -1;
 637
 638         if (! collector_list)
 639                 collector_list = sdb_llist_create();
 640         if (! collector_list)
 641                 return -1;
 642
 643         obj = sdb_object_create(name, sdb_plugin_collector_cb_type,
 644                         &collector_list, "collector", callback, user_data);
 645         if (! obj)
 646                 return -1;
 647
 648         if (interval)
 649                 SDB_PLUGIN_CCB(obj)->ccb_interval = *interval;
 650         else {
 651                 sdb_time_t tmp = sdb_plugin_get_ctx().interval;
 652
 653                 if (tmp > 0)
 654                         SDB_PLUGIN_CCB(obj)->ccb_interval = tmp;
 655                 else
 656                         SDB_PLUGIN_CCB(obj)->ccb_interval = 0;
 657         }
 658
 659         if (! (SDB_PLUGIN_CCB(obj)->ccb_next_update = sdb_gettime())) {
 660                 char errbuf[1024];
 661                 sdb_log(SDB_LOG_ERR, "core: Failed to determine current "
 662                                 "time: %s", sdb_strerror(errno, errbuf, sizeof(errbuf)));
 663                 sdb_object_deref(obj);
 664                 return -1;
 665         }
 666
 667         if (sdb_llist_insert_sorted(collector_list, obj,
 668                                 plugin_cmp_next_update)) {
 669                 sdb_object_deref(obj);
 670                 return -1;
 671         }
 672
 673         /* pass control to the list */
 674         sdb_object_deref(obj);
 675
 676         sdb_log(SDB_LOG_INFO, "core: Registered collector callback '%s' "
 677                         "(interval = %.3fs).", name,
 678                         SDB_TIME_TO_DOUBLE(SDB_PLUGIN_CCB(obj)->ccb_interval));
 679         return 0;
 680 } /* sdb_plugin_register_collector */
 681
 682 sdb_plugin_ctx_t
 683 sdb_plugin_get_ctx(void)
 684 {
 685         ctx_t *c;
 686
 687         c = ctx_get();
 688         if (! c) {
 689                 sdb_plugin_log(SDB_LOG_ERR, "core: Invalid read access to plugin "
 690                                 "context outside a plugin");
 691                 return plugin_default_ctx;
 692         }
 693         return c->public;
 694 } /* sdb_plugin_get_ctx */
 695
 696 int
 697 sdb_plugin_set_ctx(sdb_plugin_ctx_t ctx, sdb_plugin_ctx_t *old)
 698 {
 699         ctx_t *c;
 700
 701         c = ctx_get();
 702         if (! c) {
 703                 sdb_plugin_log(SDB_LOG_ERR, "core: Invalid write access to plugin "
 704                                 "context outside a plugin");
 705                 return -1;
 706         }
 707
 708         if (old)
 709                 *old = c->public;
 710         c->public = ctx;
 711         return 0;
 712 } /* sdb_plugin_set_ctx */
 713
 714 int
 715 sdb_plugin_configure(const char *name, oconfig_item_t *ci)
 716 {
 717         sdb_plugin_cb_t *plugin;
 718         sdb_plugin_config_cb callback;
 719
 720         ctx_t *old_ctx;
 721
 722         int status;
 723
 724         if ((! name) || (! ci))
 725                 return -1;
 726
 727         plugin = SDB_PLUGIN_CB(sdb_llist_search_by_name(config_list, name));
 728         if (! plugin) {
 729                 ctx_t *ctx = CTX(sdb_llist_search_by_name(all_plugins, name));
 730                 if (! ctx)
 731                         sdb_log(SDB_LOG_ERR, "core: Plugin '%s' not loaded.", name);
 732                 else
 733                         sdb_log(SDB_LOG_ERR, "core: Plugin '%s' did not register "
 734                                         "a config callback.", name);
 735                 errno = ENOENT;
 736                 return -1;
 737         }
 738
 739         old_ctx = ctx_set(plugin->cb_ctx);
 740         callback = (sdb_plugin_config_cb)plugin->cb_callback;
 741         status = callback(ci);
 742         ctx_set(old_ctx);
 743         return status;
 744 } /* sdb_plugin_configure */
 745
 746 int
 747 sdb_plugin_init_all(void)
 748 {
 749         sdb_llist_iter_t *iter;
 750         int ret = 0;
 751
 752         iter = sdb_llist_get_iter(init_list);
 753         while (sdb_llist_iter_has_next(iter)) {
 754                 sdb_plugin_cb_t *cb;
 755                 sdb_plugin_init_cb callback;
 756                 ctx_t *old_ctx;
 757
 758                 sdb_object_t *obj = sdb_llist_iter_get_next(iter);
 759                 assert(obj);
 760                 cb = SDB_PLUGIN_CB(obj);
 761
 762                 callback = (sdb_plugin_init_cb)cb->cb_callback;
 763
 764                 old_ctx = ctx_set(cb->cb_ctx);
 765                 if (callback(cb->cb_user_data)) {
 766                         sdb_log(SDB_LOG_ERR, "core: Failed to initialize plugin "
 767                                         "'%s'. Unregistering all callbacks.", obj->name);
 768                         plugin_unregister_by_name(cb->cb_ctx->info.plugin_name);
 769                         ++ret;
 770                 }
 771                 ctx_set(old_ctx);
 772         }
 773         sdb_llist_iter_destroy(iter);
 774         return ret;
 775 } /* sdb_plugin_init_all */
 776
 777 int
 778 sdb_plugin_collector_loop(sdb_plugin_loop_t *loop)
 779 {
 780         if (! collector_list) {
 781                 sdb_log(SDB_LOG_WARNING, "core: No collectors registered. "
 782                                 "Quiting main loop.");
 783                 return -1;
 784         }
 785
 786         if (! loop)
 787                 return -1;
 788
 789         while (loop->do_loop) {
 790                 sdb_plugin_collector_cb callback;
 791                 ctx_t *old_ctx;
 792
 793                 sdb_time_t interval, now;
 794
 795                 sdb_object_t *obj = sdb_llist_shift(collector_list);
 796                 if (! obj)
 797                         return -1;
 798
 799                 callback = (sdb_plugin_collector_cb)SDB_PLUGIN_CCB(obj)->ccb_callback;
 800
 801                 if (! (now = sdb_gettime())) {
 802                         char errbuf[1024];
 803                         sdb_log(SDB_LOG_ERR, "core: Failed to determine current "
 804                                         "time in collector main loop: %s",
 805                                         sdb_strerror(errno, errbuf, sizeof(errbuf)));
 806                         now = SDB_PLUGIN_CCB(obj)->ccb_next_update;
 807                 }
 808
 809                 if (now < SDB_PLUGIN_CCB(obj)->ccb_next_update) {
 810                         interval = SDB_PLUGIN_CCB(obj)->ccb_next_update - now;
 811
 812                         errno = 0;
 813                         while (loop->do_loop && sdb_sleep(interval, &interval)) {
 814                                 if (errno != EINTR) {
 815                                         char errbuf[1024];
 816                                         sdb_log(SDB_LOG_ERR, "core: Failed to sleep "
 817                                                         "in collector main loop: %s",
 818                                                         sdb_strerror(errno, errbuf, sizeof(errbuf)));
 819                                         return -1;
 820                                 }
 821                                 errno = 0;
 822                         }
 823
 824                         if (! loop->do_loop)
 825                                 return 0;
 826                 }
 827
 828                 old_ctx = ctx_set(SDB_PLUGIN_CCB(obj)->ccb_ctx);
 829                 if (callback(SDB_PLUGIN_CCB(obj)->ccb_user_data)) {
 830                         /* XXX */
 831                 }
 832                 ctx_set(old_ctx);
 833
 834                 interval = SDB_PLUGIN_CCB(obj)->ccb_interval;
 835                 if (! interval)
 836                         interval = loop->default_interval;
 837                 if (! interval) {
 838                         sdb_log(SDB_LOG_WARNING, "core: No interval configured "
 839                                         "for plugin '%s'; skipping any further "
 840                                         "iterations.", obj->name);
 841                         sdb_object_deref(obj);
 842                         continue;
 843                 }
 844
 845                 SDB_PLUGIN_CCB(obj)->ccb_next_update += interval;
 846
 847                 if (! (now = sdb_gettime())) {
 848                         char errbuf[1024];
 849                         sdb_log(SDB_LOG_ERR, "core: Failed to determine current "
 850                                         "time in collector main loop: %s",
 851                                         sdb_strerror(errno, errbuf, sizeof(errbuf)));
 852                         now = SDB_PLUGIN_CCB(obj)->ccb_next_update;
 853                 }
 854
 855                 if (now > SDB_PLUGIN_CCB(obj)->ccb_next_update) {
 856                         sdb_log(SDB_LOG_WARNING, "core: Plugin '%s' took too "
 857                                         "long; skipping iterations to keep up.",
 858                                         obj->name);
 859                         SDB_PLUGIN_CCB(obj)->ccb_next_update = now;
 860                 }
 861
 862                 if (sdb_llist_insert_sorted(collector_list, obj,
 863                                         plugin_cmp_next_update)) {
 864                         sdb_log(SDB_LOG_ERR, "core: Failed to re-insert "
 865                                         "plugin '%s' into collector list. Unable to further "
 866                                         "use the plugin.",
 867                                         obj->name);
 868                         sdb_object_deref(obj);
 869                         return -1;
 870                 }
 871
 872                 /* pass control back to the list */
 873                 sdb_object_deref(obj);
 874         }
 875         return 0;
 876 } /* sdb_plugin_read_loop */
 877
 878 char *
 879 sdb_plugin_cname(char *hostname)
 880 {
 881         sdb_llist_iter_t *iter;
 882
 883         if (! hostname)
 884                 return NULL;
 885
 886         if (! cname_list)
 887                 return hostname;
 888
 889         iter = sdb_llist_get_iter(cname_list);
 890         while (sdb_llist_iter_has_next(iter)) {
 891                 sdb_plugin_cname_cb callback;
 892                 char *cname;
 893
 894                 sdb_object_t *obj = sdb_llist_iter_get_next(iter);
 895                 assert(obj);
 896
 897                 callback = (sdb_plugin_cname_cb)SDB_PLUGIN_CB(obj)->cb_callback;
 898                 cname = callback(hostname, SDB_PLUGIN_CB(obj)->cb_user_data);
 899                 if (cname) {
 900                         free(hostname);
 901                         hostname = cname;
 902                 }
 903                 /* else: don't change hostname */
 904         }
 905         sdb_llist_iter_destroy(iter);
 906         return hostname;
 907 } /* sdb_plugin_cname */
 908
 909 int
 910 sdb_plugin_log(int prio, const char *msg)
 911 {
 912         sdb_llist_iter_t *iter;
 913         int ret = -1;
 914
 915         if (! msg)
 916                 return 0;
 917
 918         if (! log_list)
 919                 return fprintf(stderr, "[%s] %s\n", SDB_LOG_PRIO_TO_STRING(prio), msg);
 920
 921         iter = sdb_llist_get_iter(log_list);
 922         while (sdb_llist_iter_has_next(iter)) {
 923                 sdb_plugin_log_cb callback;
 924                 int tmp;
 925
 926                 sdb_object_t *obj = sdb_llist_iter_get_next(iter);
 927                 assert(obj);
 928
 929                 callback = (sdb_plugin_log_cb)SDB_PLUGIN_CB(obj)->cb_callback;
 930                 tmp = callback(prio, msg, SDB_PLUGIN_CB(obj)->cb_user_data);
 931                 if (tmp > ret)
 932                         ret = tmp;
 933         }
 934         sdb_llist_iter_destroy(iter);
 935         return ret;
 936 } /* sdb_plugin_log */
 937
 938 int
 939 sdb_plugin_vlogf(int prio, const char *fmt, va_list ap)
 940 {
 941         sdb_strbuf_t *buf;
 942         int ret;
 943
 944         if (! fmt)
 945                 return 0;
 946
 947         buf = sdb_strbuf_create(64);
 948         if (! buf) {
 949                 ret = fprintf(stderr, "[%s] ", SDB_LOG_PRIO_TO_STRING(prio));
 950                 ret += vfprintf(stderr, fmt, ap);
 951                 return ret;
 952         }
 953
 954         if (sdb_strbuf_vsprintf(buf, fmt, ap) < 0) {
 955                 sdb_strbuf_destroy(buf);
 956                 return -1;
 957         }
 958
 959         ret = sdb_plugin_log(prio, sdb_strbuf_string(buf));
 960         sdb_strbuf_destroy(buf);
 961         return ret;
 962 } /* sdb_plugin_vlogf */
 963
 964 int
 965 sdb_plugin_logf(int prio, const char *fmt, ...)
 966 {
 967         va_list ap;
 968         int ret;
 969
 970         if (! fmt)
 971                 return 0;
 972
 973         va_start(ap, fmt);
 974         ret = sdb_plugin_vlogf(prio, fmt, ap);
 975         va_end(ap);
 976         return ret;
 977 } /* sdb_plugin_logf */
 978
 979 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 980