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