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         lt_dlhandle handle;
  85
  86         /* The usage count differs from the object's ref count
  87          * in that it provides higher level information about how
  88          * the plugin is in use. */
  89         size_t use_cnt;
  90 } ctx_t;
  91 #define CTX_INIT { SDB_OBJECT_INIT, \
  92         SDB_PLUGIN_CTX_INIT, SDB_PLUGIN_INFO_INIT, NULL, 0 }
  93
  94 #define CTX(obj) ((ctx_t *)(obj))
  95
  96 typedef struct {
  97         sdb_object_t super;
  98         void *cb_callback;
  99         sdb_object_t *cb_user_data;
 100         ctx_t *cb_ctx;
 101 } sdb_plugin_cb_t;
 102 #define SDB_PLUGIN_CB_INIT { SDB_OBJECT_INIT, \
 103         /* callback = */ NULL, /* user_data = */ NULL, \
 104         SDB_PLUGIN_CTX_INIT }
 105
 106 typedef struct {
 107         sdb_plugin_cb_t super;
 108 #define ccb_callback super.cb_callback
 109 #define ccb_user_data super.cb_user_data
 110 #define ccb_ctx super.cb_ctx
 111         sdb_time_t ccb_interval;
 112         sdb_time_t ccb_next_update;
 113 } sdb_plugin_collector_cb_t;
 114
 115 #define SDB_PLUGIN_CB(obj) ((sdb_plugin_cb_t *)(obj))
 116 #define SDB_CONST_PLUGIN_CB(obj) ((const sdb_plugin_cb_t *)(obj))
 117 #define SDB_PLUGIN_CCB(obj) ((sdb_plugin_collector_cb_t *)(obj))
 118 #define SDB_CONST_PLUGIN_CCB(obj) ((const sdb_plugin_collector_cb_t *)(obj))
 119
 120 /*
 121  * private variables
 122  */
 123
 124 static sdb_plugin_ctx_t  plugin_default_ctx  = SDB_PLUGIN_CTX_INIT;
 125 static sdb_plugin_info_t plugin_default_info = SDB_PLUGIN_INFO_INIT;
 126
 127 static pthread_key_t     plugin_ctx_key;
 128 static _Bool             plugin_ctx_key_initialized = 0;
 129
 130 /* a list of the plugin contexts of all registered plugins */
 131 static sdb_llist_t      *all_plugins = NULL;
 132
 133 static sdb_llist_t      *config_list = NULL;
 134 static sdb_llist_t      *init_list = NULL;
 135 static sdb_llist_t      *collector_list = NULL;
 136 static sdb_llist_t      *cname_list = NULL;
 137 static sdb_llist_t      *shutdown_list = NULL;
 138 static sdb_llist_t      *log_list = NULL;
 139
 140 /*
 141  * private helper functions
 142  */
 143
 144 static void
 145 plugin_info_clear(sdb_plugin_info_t *info)
 146 {
 147         sdb_plugin_info_t empty_info = SDB_PLUGIN_INFO_INIT;
 148         if (! info)
 149                 return;
 150
 151         if (info->plugin_name)
 152                 free(info->plugin_name);
 153         if (info->filename)
 154                 free(info->filename);
 155
 156         if (info->name)
 157                 free(info->name);
 158         if (info->description)
 159                 free(info->description);
 160         if (info->copyright)
 161                 free(info->copyright);
 162         if (info->license)
 163                 free(info->license);
 164
 165         *info = empty_info;
 166 } /* plugin_info_clear */
 167
 168 static void
 169 ctx_key_init(void)
 170 {
 171         if (plugin_ctx_key_initialized)
 172                 return;
 173
 174         pthread_key_create(&plugin_ctx_key, /* destructor */ NULL);
 175         plugin_ctx_key_initialized = 1;
 176 } /* ctx_key_init */
 177
 178 static int
 179 plugin_cmp_next_update(const sdb_object_t *a, const sdb_object_t *b)
 180 {
 181         const sdb_plugin_collector_cb_t *ccb1
 182                 = (const sdb_plugin_collector_cb_t *)a;
 183         const sdb_plugin_collector_cb_t *ccb2
 184                 = (const sdb_plugin_collector_cb_t *)b;
 185
 186         assert(ccb1 && ccb2);
 187
 188         return (ccb1->ccb_next_update > ccb2->ccb_next_update)
 189                 ? 1 : (ccb1->ccb_next_update < ccb2->ccb_next_update)
 190                 ? -1 : 0;
 191 } /* plugin_cmp_next_update */
 192
 193 static int
 194 plugin_lookup_by_name(const sdb_object_t *obj, const void *id)
 195 {
 196         const sdb_plugin_cb_t *cb = SDB_CONST_PLUGIN_CB(obj);
 197         const char *name = id;
 198
 199         assert(cb && id && cb->cb_ctx);
 200         if (!strcasecmp(cb->cb_ctx->info.plugin_name, name))
 201                 return 0;
 202         return 1;
 203 } /* plugin_lookup_by_name */
 204
 205 static void
 206 plugin_unregister_by_name(const char *plugin_name)
 207 {
 208         sdb_object_t *obj;
 209         size_t i;
 210
 211         struct {
 212                 const char  *type;
 213                 sdb_llist_t *list;
 214         } all_lists[] = {
 215                 { "config",    config_list },
 216                 { "init",      init_list },
 217                 { "collector", collector_list },
 218                 { "cname",     cname_list },
 219                 { "shutdown",  shutdown_list },
 220                 { "log",       log_list },
 221         };
 222
 223         for (i = 0; i < SDB_STATIC_ARRAY_LEN(all_lists); ++i) {
 224                 const char  *type = all_lists[i].type;
 225                 sdb_llist_t *list = all_lists[i].list;
 226
 227                 while (1) {
 228                         sdb_plugin_cb_t *cb;
 229
 230                         cb = SDB_PLUGIN_CB(sdb_llist_remove(list,
 231                                                 plugin_lookup_by_name, plugin_name));
 232                         if (! cb)
 233                                 break;
 234
 235                         sdb_log(SDB_LOG_INFO, "core: Unregistering "
 236                                         "%s callback '%s' (module %s)", type, cb->super.name,
 237                                         cb->cb_ctx->info.plugin_name);
 238                         sdb_object_deref(SDB_OBJ(cb));
 239                 }
 240         }
 241
 242         obj = sdb_llist_remove_by_name(all_plugins, plugin_name);
 243         if (obj->ref_cnt <= 1)
 244                 sdb_log(SDB_LOG_INFO, "core: Unloading module %s", plugin_name);
 245         /* else: other callbacks still reference it */
 246         sdb_object_deref(obj);
 247 } /* plugin_unregister_by_name */
 248
 249 /*
 250  * private types
 251  */
 252
 253 static int
 254 ctx_init(sdb_object_t *obj, va_list __attribute__((unused)) ap)
 255 {
 256         ctx_t *ctx = CTX(obj);
 257
 258         assert(ctx);
 259
 260         ctx->public = plugin_default_ctx;
 261         ctx->info = plugin_default_info;
 262         ctx->handle = NULL;
 263         ctx->use_cnt = 1;
 264         return 0;
 265 } /* ctx_init */
 266
 267 static void
 268 ctx_destroy(sdb_object_t *obj)
 269 {
 270         ctx_t *ctx = CTX(obj);
 271
 272         if (ctx->handle) {
 273                 const char *err;
 274                 lt_dlerror();
 275                 lt_dlclose(ctx->handle);
 276                 if ((err = lt_dlerror()))
 277                         sdb_log(SDB_LOG_WARNING, "core: Failed to unload plugin %s: %s",
 278                                         ctx->info.plugin_name, err);
 279         }
 280
 281         plugin_info_clear(&ctx->info);
 282 } /* ctx_destroy */
 283
 284 static sdb_type_t ctx_type = {
 285         sizeof(ctx_t),
 286
 287         ctx_init,
 288         ctx_destroy
 289 };
 290
 291 static ctx_t *
 292 ctx_create(const char *name)
 293 {
 294         ctx_t *ctx;
 295
 296         ctx = CTX(sdb_object_create(name, ctx_type));
 297         if (! ctx)
 298                 return NULL;
 299
 300         if (! plugin_ctx_key_initialized)
 301                 ctx_key_init();
 302         pthread_setspecific(plugin_ctx_key, ctx);
 303         return ctx;
 304 } /* ctx_create */
 305
 306 static ctx_t *
 307 ctx_get(void)
 308 {
 309         if (! plugin_ctx_key_initialized)
 310                 ctx_key_init();
 311         return pthread_getspecific(plugin_ctx_key);
 312 } /* ctx_get */
 313
 314 static ctx_t *
 315 ctx_set(ctx_t *new)
 316 {
 317         ctx_t *old;
 318
 319         if (! plugin_ctx_key_initialized)
 320                 ctx_key_init();
 321
 322         old = pthread_getspecific(plugin_ctx_key);
 323         pthread_setspecific(plugin_ctx_key, new);
 324         return old;
 325 } /* ctx_set */
 326
 327 static int
 328 plugin_cb_init(sdb_object_t *obj, va_list ap)
 329 {
 330         sdb_llist_t **list = va_arg(ap, sdb_llist_t **);
 331         const char   *type = va_arg(ap, const char *);
 332         void     *callback = va_arg(ap, void *);
 333         sdb_object_t   *ud = va_arg(ap, sdb_object_t *);
 334
 335         assert(list);
 336         assert(type);
 337         assert(obj);
 338
 339         if (sdb_llist_search_by_name(*list, obj->name)) {
 340                 sdb_log(SDB_LOG_WARNING, "core: %s callback '%s' "
 341                                 "has already been registered. Ignoring newly "
 342                                 "registered version.", type, obj->name);
 343                 return -1;
 344         }
 345
 346         SDB_PLUGIN_CB(obj)->cb_callback = callback;
 347         SDB_PLUGIN_CB(obj)->cb_ctx      = ctx_get();
 348         sdb_object_ref(SDB_OBJ(SDB_PLUGIN_CB(obj)->cb_ctx));
 349
 350         sdb_object_ref(ud);
 351         SDB_PLUGIN_CB(obj)->cb_user_data = ud;
 352         return 0;
 353 } /* plugin_cb_init */
 354
 355 static void
 356 plugin_cb_destroy(sdb_object_t *obj)
 357 {
 358         assert(obj);
 359         sdb_object_deref(SDB_PLUGIN_CB(obj)->cb_user_data);
 360         sdb_object_deref(SDB_OBJ(SDB_PLUGIN_CB(obj)->cb_ctx));
 361 } /* plugin_cb_destroy */
 362
 363 static sdb_type_t sdb_plugin_cb_type = {
 364         sizeof(sdb_plugin_cb_t),
 365
 366         plugin_cb_init,
 367         plugin_cb_destroy
 368 };
 369
 370 static sdb_type_t sdb_plugin_collector_cb_type = {
 371         sizeof(sdb_plugin_collector_cb_t),
 372
 373         plugin_cb_init,
 374         plugin_cb_destroy
 375 };
 376
 377 static int
 378 plugin_add_callback(sdb_llist_t **list, const char *type,
 379                 const char *name, void *callback, sdb_object_t *user_data)
 380 {
 381         sdb_object_t *obj;
 382
 383         if ((! name) || (! callback))
 384                 return -1;
 385
 386         assert(list);
 387
 388         if (! *list)
 389                 *list = sdb_llist_create();
 390         if (! *list)
 391                 return -1;
 392
 393         obj = sdb_object_create(name, sdb_plugin_cb_type,
 394                         list, type, callback, user_data);
 395         if (! obj)
 396                 return -1;
 397
 398         if (sdb_llist_append(*list, obj)) {
 399                 sdb_object_deref(obj);
 400                 return -1;
 401         }
 402
 403         /* pass control to the list */
 404         sdb_object_deref(obj);
 405
 406         sdb_log(SDB_LOG_INFO, "core: Registered %s callback '%s'.",
 407                         type, name);
 408         return 0;
 409 } /* plugin_add_callback */
 410
 411 /*
 412  * public API
 413  */
 414
 415 int
 416 sdb_plugin_load(const char *name, const sdb_plugin_ctx_t *plugin_ctx)
 417 {
 418         char  base_name[name ? strlen(name) + 1 : 1];
 419         const char *name_ptr;
 420         char *tmp;
 421
 422         char filename[1024];
 423         ctx_t *ctx;
 424
 425         lt_dlhandle lh;
 426
 427         int (*mod_init)(sdb_plugin_info_t *);
 428         int status;
 429
 430         if ((! name) || (! *name))
 431                 return -1;
 432
 433         base_name[0] = '\0';
 434         name_ptr = name;
 435
 436         while ((tmp = strstr(name_ptr, "::"))) {
 437                 strncat(base_name, name_ptr, (size_t)(tmp - name_ptr));
 438                 strcat(base_name, "/");
 439                 name_ptr = tmp + strlen("::");
 440         }
 441         strcat(base_name, name_ptr);
 442
 443         ctx = CTX(sdb_llist_search_by_name(all_plugins, base_name));
 444         if (ctx) {
 445                 /* plugin already loaded */
 446                 ++ctx->use_cnt;
 447                 return 0;
 448         }
 449
 450         snprintf(filename, sizeof(filename), "%s/%s.so",
 451                         PKGLIBDIR, base_name);
 452         filename[sizeof(filename) - 1] = '\0';
 453
 454         if (access(filename, R_OK)) {
 455                 char errbuf[1024];
 456                 sdb_log(SDB_LOG_ERR, "core: Failed to load plugin '%s' (%s): %s",
 457                                 name, filename, sdb_strerror(errno, errbuf, sizeof(errbuf)));
 458                 return -1;
 459         }
 460
 461         lt_dlinit();
 462         lt_dlerror();
 463
 464         lh = lt_dlopen(filename);
 465         if (! lh) {
 466                 sdb_log(SDB_LOG_ERR, "core: Failed to load plugin '%s': %s"
 467                                 "The most common cause for this problem are missing "
 468                                 "dependencies.\n", name, lt_dlerror());
 469                 return -1;
 470         }
 471
 472         if (ctx_get())
 473                 sdb_log(SDB_LOG_WARNING, "core: Discarding old plugin context");
 474
 475         ctx = ctx_create(name);
 476         if (! ctx) {
 477                 sdb_log(SDB_LOG_ERR, "core: Failed to initialize plugin context");
 478                 return -1;
 479         }
 480
 481         ctx->info.plugin_name = strdup(name);
 482         ctx->info.filename = strdup(filename);
 483         ctx->handle = lh;
 484
 485         if (plugin_ctx)
 486                 ctx->public = *plugin_ctx;
 487
 488         mod_init = (int (*)(sdb_plugin_info_t *))lt_dlsym(lh, "sdb_module_init");
 489         if (! mod_init) {
 490                 sdb_log(SDB_LOG_ERR, "core: Failed to load plugin '%s': "
 491                                 "could not find symbol 'sdb_module_init'", name);
 492                 sdb_object_deref(SDB_OBJ(ctx));
 493                 return -1;
 494         }
 495
 496         status = mod_init(&ctx->info);
 497         if (status) {
 498                 sdb_log(SDB_LOG_ERR, "core: Failed to initialize "
 499                                 "module '%s'", name);
 500                 plugin_unregister_by_name(ctx->info.plugin_name);
 501                 sdb_object_deref(SDB_OBJ(ctx));
 502                 return -1;
 503         }
 504
 505         /* compare minor version */
 506         if ((ctx->info.version < 0)
 507                         || ((int)(ctx->info.version / 100) != (int)(SDB_VERSION / 100)))
 508                 sdb_log(SDB_LOG_WARNING, "core: WARNING: version of "
 509                                 "plugin '%s' (%i.%i.%i) does not match our version "
 510                                 "(%i.%i.%i); this might cause problems",
 511                                 name, SDB_VERSION_DECODE(ctx->info.version),
 512                                 SDB_VERSION_DECODE(SDB_VERSION));
 513
 514         if (! all_plugins) {
 515                 if (! (all_plugins = sdb_llist_create())) {
 516                         sdb_log(SDB_LOG_ERR, "core: Failed to load plugin '%s': "
 517                                         "internal error while creating linked list", name);
 518                         plugin_unregister_by_name(ctx->info.plugin_name);
 519                         sdb_object_deref(SDB_OBJ(ctx));
 520                         return -1;
 521                 }
 522         }
 523
 524         sdb_llist_append(all_plugins, SDB_OBJ(ctx));
 525
 526         sdb_log(SDB_LOG_INFO, "core: Successfully loaded "
 527                         "plugin '%s' v%i (%s)\n\t%s\n\tLicense: %s",
 528                         INFO_GET(&ctx->info, name), ctx->info.plugin_version,
 529                         INFO_GET(&ctx->info, description),
 530                         INFO_GET(&ctx->info, copyright),
 531                         INFO_GET(&ctx->info, license));
 532
 533         /* any registered callbacks took ownership of the context */
 534         sdb_object_deref(SDB_OBJ(ctx));
 535
 536         /* reset */
 537         ctx_set(NULL);
 538         return 0;
 539 } /* sdb_plugin_load */
 540
 541 int
 542 sdb_plugin_set_info(sdb_plugin_info_t *info, int type, ...)
 543 {
 544         va_list ap;
 545
 546         if (! info)
 547                 return -1;
 548
 549         va_start(ap, type);
 550
 551         switch (type) {
 552                 case SDB_PLUGIN_INFO_NAME:
 553                         {
 554                                 char *name = va_arg(ap, char *);
 555                                 if (name) {
 556                                         if (info->name)
 557                                                 free(info->name);
 558                                         info->name = strdup(name);
 559                                 }
 560                         }
 561                         break;
 562                 case SDB_PLUGIN_INFO_DESC:
 563                         {
 564                                 char *desc = va_arg(ap, char *);
 565                                 if (desc) {
 566                                         if (info->description)
 567                                                 free(info->description);
 568                                         info->description = strdup(desc);
 569                                 }
 570                         }
 571                         break;
 572                 case SDB_PLUGIN_INFO_COPYRIGHT:
 573                         {
 574                                 char *copyright = va_arg(ap, char *);
 575                                 if (copyright)
 576                                         info->copyright = strdup(copyright);
 577                         }
 578                         break;
 579                 case SDB_PLUGIN_INFO_LICENSE:
 580                         {
 581                                 char *license = va_arg(ap, char *);
 582                                 if (license) {
 583                                         if (info->license)
 584                                                 free(info->license);
 585                                         info->license = strdup(license);
 586                                 }
 587                         }
 588                         break;
 589                 case SDB_PLUGIN_INFO_VERSION:
 590                         {
 591                                 int version = va_arg(ap, int);
 592                                 info->version = version;
 593                         }
 594                         break;
 595                 case SDB_PLUGIN_INFO_PLUGIN_VERSION:
 596                         {
 597                                 int version = va_arg(ap, int);
 598                                 info->plugin_version = version;
 599                         }
 600                         break;
 601                 default:
 602                         va_end(ap);
 603                         return -1;
 604         }
 605
 606         va_end(ap);
 607         return 0;
 608 } /* sdb_plugin_set_info */
 609
 610 int
 611 sdb_plugin_register_config(const char *name, sdb_plugin_config_cb callback)
 612 {
 613         return plugin_add_callback(&config_list, "init", name,
 614                         (void *)callback, NULL);
 615 } /* sdb_plugin_register_config */
 616
 617 int
 618 sdb_plugin_register_init(const char *name, sdb_plugin_init_cb callback,
 619                 sdb_object_t *user_data)
 620 {
 621         return plugin_add_callback(&init_list, "init", name,
 622                         (void *)callback, user_data);
 623 } /* sdb_plugin_register_init */
 624
 625 int
 626 sdb_plugin_register_shutdown(const char *name, sdb_plugin_shutdown_cb callback,
 627                 sdb_object_t *user_data)
 628 {
 629         return plugin_add_callback(&shutdown_list, "shutdown", name,
 630                         (void *)callback, user_data);
 631 } /* sdb_plugin_register_shutdown */
 632
 633 int
 634 sdb_plugin_register_log(const char *name, sdb_plugin_log_cb callback,
 635                 sdb_object_t *user_data)
 636 {
 637         return plugin_add_callback(&log_list, "log", name, (void *)callback,
 638                         user_data);
 639 } /* sdb_plugin_register_log */
 640
 641 int
 642 sdb_plugin_register_cname(const char *name, sdb_plugin_cname_cb callback,
 643                 sdb_object_t *user_data)
 644 {
 645         return plugin_add_callback(&cname_list, "cname", name, (void *)callback,
 646                         user_data);
 647 } /* sdb_plugin_register_cname */
 648
 649 int
 650 sdb_plugin_register_collector(const char *name, sdb_plugin_collector_cb callback,
 651                 const sdb_time_t *interval, sdb_object_t *user_data)
 652 {
 653         sdb_object_t *obj;
 654
 655         if ((! name) || (! callback))
 656                 return -1;
 657
 658         if (! collector_list)
 659                 collector_list = sdb_llist_create();
 660         if (! collector_list)
 661                 return -1;
 662
 663         obj = sdb_object_create(name, sdb_plugin_collector_cb_type,
 664                         &collector_list, "collector", callback, user_data);
 665         if (! obj)
 666                 return -1;
 667
 668         if (interval)
 669                 SDB_PLUGIN_CCB(obj)->ccb_interval = *interval;
 670         else {
 671                 sdb_time_t tmp = sdb_plugin_get_ctx().interval;
 672
 673                 if (tmp > 0)
 674                         SDB_PLUGIN_CCB(obj)->ccb_interval = tmp;
 675                 else
 676                         SDB_PLUGIN_CCB(obj)->ccb_interval = 0;
 677         }
 678
 679         if (! (SDB_PLUGIN_CCB(obj)->ccb_next_update = sdb_gettime())) {
 680                 char errbuf[1024];
 681                 sdb_log(SDB_LOG_ERR, "core: Failed to determine current "
 682                                 "time: %s", sdb_strerror(errno, errbuf, sizeof(errbuf)));
 683                 sdb_object_deref(obj);
 684                 return -1;
 685         }
 686
 687         if (sdb_llist_insert_sorted(collector_list, obj,
 688                                 plugin_cmp_next_update)) {
 689                 sdb_object_deref(obj);
 690                 return -1;
 691         }
 692
 693         /* pass control to the list */
 694         sdb_object_deref(obj);
 695
 696         sdb_log(SDB_LOG_INFO, "core: Registered collector callback '%s' "
 697                         "(interval = %.3fs).", name,
 698                         SDB_TIME_TO_DOUBLE(SDB_PLUGIN_CCB(obj)->ccb_interval));
 699         return 0;
 700 } /* sdb_plugin_register_collector */
 701
 702 sdb_plugin_ctx_t
 703 sdb_plugin_get_ctx(void)
 704 {
 705         ctx_t *c;
 706
 707         c = ctx_get();
 708         if (! c) {
 709                 sdb_plugin_log(SDB_LOG_ERR, "core: Invalid read access to plugin "
 710                                 "context outside a plugin");
 711                 return plugin_default_ctx;
 712         }
 713         return c->public;
 714 } /* sdb_plugin_get_ctx */
 715
 716 int
 717 sdb_plugin_set_ctx(sdb_plugin_ctx_t ctx, sdb_plugin_ctx_t *old)
 718 {
 719         ctx_t *c;
 720
 721         c = ctx_get();
 722         if (! c) {
 723                 sdb_plugin_log(SDB_LOG_ERR, "core: Invalid write access to plugin "
 724                                 "context outside a plugin");
 725                 return -1;
 726         }
 727
 728         if (old)
 729                 *old = c->public;
 730         c->public = ctx;
 731         return 0;
 732 } /* sdb_plugin_set_ctx */
 733
 734 int
 735 sdb_plugin_configure(const char *name, oconfig_item_t *ci)
 736 {
 737         sdb_plugin_cb_t *plugin;
 738         sdb_plugin_config_cb callback;
 739
 740         ctx_t *old_ctx;
 741
 742         int status;
 743
 744         if ((! name) || (! ci))
 745                 return -1;
 746
 747         plugin = SDB_PLUGIN_CB(sdb_llist_search_by_name(config_list, name));
 748         if (! plugin) {
 749                 ctx_t *ctx = CTX(sdb_llist_search_by_name(all_plugins, name));
 750                 if (! ctx)
 751                         sdb_log(SDB_LOG_ERR, "core: Plugin '%s' not loaded.", name);
 752                 else
 753                         sdb_log(SDB_LOG_ERR, "core: Plugin '%s' did not register "
 754                                         "a config callback.", name);
 755                 errno = ENOENT;
 756                 return -1;
 757         }
 758
 759         old_ctx = ctx_set(plugin->cb_ctx);
 760         callback = (sdb_plugin_config_cb)plugin->cb_callback;
 761         status = callback(ci);
 762         ctx_set(old_ctx);
 763         return status;
 764 } /* sdb_plugin_configure */
 765
 766 int
 767 sdb_plugin_init_all(void)
 768 {
 769         sdb_llist_iter_t *iter;
 770         int ret = 0;
 771
 772         iter = sdb_llist_get_iter(init_list);
 773         while (sdb_llist_iter_has_next(iter)) {
 774                 sdb_plugin_cb_t *cb;
 775                 sdb_plugin_init_cb callback;
 776                 ctx_t *old_ctx;
 777
 778                 sdb_object_t *obj = sdb_llist_iter_get_next(iter);
 779                 assert(obj);
 780                 cb = SDB_PLUGIN_CB(obj);
 781
 782                 callback = (sdb_plugin_init_cb)cb->cb_callback;
 783
 784                 old_ctx = ctx_set(cb->cb_ctx);
 785                 if (callback(cb->cb_user_data)) {
 786                         sdb_log(SDB_LOG_ERR, "core: Failed to initialize plugin "
 787                                         "'%s'. Unregistering all callbacks.", obj->name);
 788                         plugin_unregister_by_name(cb->cb_ctx->info.plugin_name);
 789                         ++ret;
 790                 }
 791                 ctx_set(old_ctx);
 792         }
 793         sdb_llist_iter_destroy(iter);
 794         return ret;
 795 } /* sdb_plugin_init_all */
 796
 797 int
 798 sdb_plugin_collector_loop(sdb_plugin_loop_t *loop)
 799 {
 800         if (! collector_list) {
 801                 sdb_log(SDB_LOG_WARNING, "core: No collectors registered. "
 802                                 "Quiting main loop.");
 803                 return -1;
 804         }
 805
 806         if (! loop)
 807                 return -1;
 808
 809         while (loop->do_loop) {
 810                 sdb_plugin_collector_cb callback;
 811                 ctx_t *old_ctx;
 812
 813                 sdb_time_t interval, now;
 814
 815                 sdb_object_t *obj = sdb_llist_shift(collector_list);
 816                 if (! obj)
 817                         return -1;
 818
 819                 callback = (sdb_plugin_collector_cb)SDB_PLUGIN_CCB(obj)->ccb_callback;
 820
 821                 if (! (now = sdb_gettime())) {
 822                         char errbuf[1024];
 823                         sdb_log(SDB_LOG_ERR, "core: Failed to determine current "
 824                                         "time in collector main loop: %s",
 825                                         sdb_strerror(errno, errbuf, sizeof(errbuf)));
 826                         now = SDB_PLUGIN_CCB(obj)->ccb_next_update;
 827                 }
 828
 829                 if (now < SDB_PLUGIN_CCB(obj)->ccb_next_update) {
 830                         interval = SDB_PLUGIN_CCB(obj)->ccb_next_update - now;
 831
 832                         errno = 0;
 833                         while (loop->do_loop && sdb_sleep(interval, &interval)) {
 834                                 if (errno != EINTR) {
 835                                         char errbuf[1024];
 836                                         sdb_log(SDB_LOG_ERR, "core: Failed to sleep "
 837                                                         "in collector main loop: %s",
 838                                                         sdb_strerror(errno, errbuf, sizeof(errbuf)));
 839                                         return -1;
 840                                 }
 841                                 errno = 0;
 842                         }
 843
 844                         if (! loop->do_loop)
 845                                 return 0;
 846                 }
 847
 848                 old_ctx = ctx_set(SDB_PLUGIN_CCB(obj)->ccb_ctx);
 849                 if (callback(SDB_PLUGIN_CCB(obj)->ccb_user_data)) {
 850                         /* XXX */
 851                 }
 852                 ctx_set(old_ctx);
 853
 854                 interval = SDB_PLUGIN_CCB(obj)->ccb_interval;
 855                 if (! interval)
 856                         interval = loop->default_interval;
 857                 if (! interval) {
 858                         sdb_log(SDB_LOG_WARNING, "core: No interval configured "
 859                                         "for plugin '%s'; skipping any further "
 860                                         "iterations.", obj->name);
 861                         sdb_object_deref(obj);
 862                         continue;
 863                 }
 864
 865                 SDB_PLUGIN_CCB(obj)->ccb_next_update += interval;
 866
 867                 if (! (now = sdb_gettime())) {
 868                         char errbuf[1024];
 869                         sdb_log(SDB_LOG_ERR, "core: Failed to determine current "
 870                                         "time in collector main loop: %s",
 871                                         sdb_strerror(errno, errbuf, sizeof(errbuf)));
 872                         now = SDB_PLUGIN_CCB(obj)->ccb_next_update;
 873                 }
 874
 875                 if (now > SDB_PLUGIN_CCB(obj)->ccb_next_update) {
 876                         sdb_log(SDB_LOG_WARNING, "core: Plugin '%s' took too "
 877                                         "long; skipping iterations to keep up.",
 878                                         obj->name);
 879                         SDB_PLUGIN_CCB(obj)->ccb_next_update = now;
 880                 }
 881
 882                 if (sdb_llist_insert_sorted(collector_list, obj,
 883                                         plugin_cmp_next_update)) {
 884                         sdb_log(SDB_LOG_ERR, "core: Failed to re-insert "
 885                                         "plugin '%s' into collector list. Unable to further "
 886                                         "use the plugin.",
 887                                         obj->name);
 888                         sdb_object_deref(obj);
 889                         return -1;
 890                 }
 891
 892                 /* pass control back to the list */
 893                 sdb_object_deref(obj);
 894         }
 895         return 0;
 896 } /* sdb_plugin_read_loop */
 897
 898 char *
 899 sdb_plugin_cname(char *hostname)
 900 {
 901         sdb_llist_iter_t *iter;
 902
 903         if (! hostname)
 904                 return NULL;
 905
 906         if (! cname_list)
 907                 return hostname;
 908
 909         iter = sdb_llist_get_iter(cname_list);
 910         while (sdb_llist_iter_has_next(iter)) {
 911                 sdb_plugin_cname_cb callback;
 912                 char *cname;
 913
 914                 sdb_object_t *obj = sdb_llist_iter_get_next(iter);
 915                 assert(obj);
 916
 917                 callback = (sdb_plugin_cname_cb)SDB_PLUGIN_CB(obj)->cb_callback;
 918                 cname = callback(hostname, SDB_PLUGIN_CB(obj)->cb_user_data);
 919                 if (cname) {
 920                         free(hostname);
 921                         hostname = cname;
 922                 }
 923                 /* else: don't change hostname */
 924         }
 925         sdb_llist_iter_destroy(iter);
 926         return hostname;
 927 } /* sdb_plugin_cname */
 928
 929 int
 930 sdb_plugin_log(int prio, const char *msg)
 931 {
 932         sdb_llist_iter_t *iter;
 933         int ret = -1;
 934
 935         if (! msg)
 936                 return 0;
 937
 938         if (! log_list)
 939                 return fprintf(stderr, "[%s] %s\n", SDB_LOG_PRIO_TO_STRING(prio), msg);
 940
 941         iter = sdb_llist_get_iter(log_list);
 942         while (sdb_llist_iter_has_next(iter)) {
 943                 sdb_plugin_log_cb callback;
 944                 int tmp;
 945
 946                 sdb_object_t *obj = sdb_llist_iter_get_next(iter);
 947                 assert(obj);
 948
 949                 callback = (sdb_plugin_log_cb)SDB_PLUGIN_CB(obj)->cb_callback;
 950                 tmp = callback(prio, msg, SDB_PLUGIN_CB(obj)->cb_user_data);
 951                 if (tmp > ret)
 952                         ret = tmp;
 953         }
 954         sdb_llist_iter_destroy(iter);
 955         return ret;
 956 } /* sdb_plugin_log */
 957
 958 int
 959 sdb_plugin_vlogf(int prio, const char *fmt, va_list ap)
 960 {
 961         sdb_strbuf_t *buf;
 962         int ret;
 963
 964         if (! fmt)
 965                 return 0;
 966
 967         buf = sdb_strbuf_create(64);
 968         if (! buf) {
 969                 ret = fprintf(stderr, "[%s] ", SDB_LOG_PRIO_TO_STRING(prio));
 970                 ret += vfprintf(stderr, fmt, ap);
 971                 return ret;
 972         }
 973
 974         if (sdb_strbuf_vsprintf(buf, fmt, ap) < 0) {
 975                 sdb_strbuf_destroy(buf);
 976                 return -1;
 977         }
 978
 979         ret = sdb_plugin_log(prio, sdb_strbuf_string(buf));
 980         sdb_strbuf_destroy(buf);
 981         return ret;
 982 } /* sdb_plugin_vlogf */
 983
 984 int
 985 sdb_plugin_logf(int prio, const char *fmt, ...)
 986 {
 987         va_list ap;
 988         int ret;
 989
 990         if (! fmt)
 991                 return 0;
 992
 993         va_start(ap, fmt);
 994         ret = sdb_plugin_vlogf(prio, fmt, ap);
 995         va_end(ap);
 996         return ret;
 997 } /* sdb_plugin_logf */
 998
 999 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
1000