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