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