src/core/store.c

   1 /*
   2  * SysDB - src/core/store.c
   3  * Copyright (C) 2012-2013 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/store-private.h"
  34 #include "core/plugin.h"
  35 #include "utils/error.h"
  36 #include "utils/llist.h"
  37
  38 #include <assert.h>
  39
  40 #include <errno.h>
  41
  42 #include <stdio.h>
  43 #include <stdlib.h>
  44 #include <string.h>
  45
  46 #include <pthread.h>
  47
  48 /*
  49  * private variables
  50  */
  51
  52 static sdb_llist_t *host_list = NULL;
  53 static pthread_rwlock_t host_lock = PTHREAD_RWLOCK_INITIALIZER;
  54
  55 /*
  56  * private types
  57  */
  58
  59 static sdb_type_t sdb_host_type;
  60 static sdb_type_t sdb_service_type;
  61 static sdb_type_t sdb_attribute_type;
  62
  63 static int
  64 store_obj_init(sdb_object_t *obj, va_list ap)
  65 {
  66         sdb_store_obj_t *sobj = STORE_OBJ(obj);
  67
  68         sobj->type = va_arg(ap, int);
  69
  70         sobj->last_update = va_arg(ap, sdb_time_t);
  71         sobj->interval = 0;
  72         sobj->backends = NULL;
  73         sobj->backends_num = 0;
  74         sobj->parent = NULL;
  75         return 0;
  76 } /* store_obj_init */
  77
  78 static void
  79 store_obj_destroy(sdb_object_t *obj)
  80 {
  81         sdb_store_obj_t *sobj = STORE_OBJ(obj);
  82         size_t i;
  83
  84         for (i = 0; i < sobj->backends_num; ++i)
  85                 free(sobj->backends[i]);
  86         free(sobj->backends);
  87         sobj->backends = NULL;
  88         sobj->backends_num = 0;
  89
  90         if (sobj->parent)
  91                 sdb_object_deref(SDB_OBJ(sobj->parent));
  92 } /* store_obj_destroy */
  93
  94 static int
  95 sdb_host_init(sdb_object_t *obj, va_list ap)
  96 {
  97         sdb_host_t *sobj = HOST(obj);
  98         int ret;
  99
 100         /* this will consume the first argument (type) of ap */
 101         ret = store_obj_init(obj, ap);
 102         if (ret)
 103                 return ret;
 104
 105         sobj->services = sdb_llist_create();
 106         if (! sobj->services)
 107                 return -1;
 108         sobj->attributes = sdb_llist_create();
 109         if (! sobj->attributes)
 110                 return -1;
 111         return 0;
 112 } /* sdb_host_init */
 113
 114 static void
 115 sdb_host_destroy(sdb_object_t *obj)
 116 {
 117         sdb_host_t *sobj = HOST(obj);
 118         assert(obj);
 119
 120         store_obj_destroy(obj);
 121
 122         if (sobj->services)
 123                 sdb_llist_destroy(sobj->services);
 124         if (sobj->attributes)
 125                 sdb_llist_destroy(sobj->attributes);
 126 } /* sdb_host_destroy */
 127
 128 static int
 129 sdb_service_init(sdb_object_t *obj, va_list ap)
 130 {
 131         sdb_service_t *sobj = SVC(obj);
 132         int ret;
 133
 134         /* this will consume the first argument (type) of ap */
 135         ret = store_obj_init(obj, ap);
 136         if (ret)
 137                 return ret;
 138
 139         sobj->attributes = sdb_llist_create();
 140         if (! sobj->attributes)
 141                 return -1;
 142         return 0;
 143 } /* sdb_service_init */
 144
 145 static void
 146 sdb_service_destroy(sdb_object_t *obj)
 147 {
 148         sdb_service_t *sobj = SVC(obj);
 149         assert(obj);
 150
 151         store_obj_destroy(obj);
 152
 153         if (sobj->attributes)
 154                 sdb_llist_destroy(sobj->attributes);
 155 } /* sdb_service_destroy */
 156
 157 static int
 158 sdb_attr_init(sdb_object_t *obj, va_list ap)
 159 {
 160         const sdb_data_t *value;
 161         int ret;
 162
 163         /* this will consume the first two arguments
 164          * (type and last_update) of ap */
 165         ret = store_obj_init(obj, ap);
 166         if (ret)
 167                 return ret;
 168         value = va_arg(ap, const sdb_data_t *);
 169
 170         if (value)
 171                 if (sdb_data_copy(&ATTR(obj)->value, value))
 172                         return -1;
 173         return 0;
 174 } /* sdb_attr_init */
 175
 176 static void
 177 sdb_attr_destroy(sdb_object_t *obj)
 178 {
 179         assert(obj);
 180
 181         store_obj_destroy(obj);
 182         sdb_data_free_datum(&ATTR(obj)->value);
 183 } /* sdb_attr_destroy */
 184
 185 static sdb_type_t sdb_host_type = {
 186         sizeof(sdb_host_t),
 187         sdb_host_init,
 188         sdb_host_destroy
 189 };
 190
 191 static sdb_type_t sdb_service_type = {
 192         sizeof(sdb_service_t),
 193         sdb_service_init,
 194         sdb_service_destroy
 195 };
 196
 197 static sdb_type_t sdb_attribute_type = {
 198         sizeof(sdb_attribute_t),
 199         sdb_attr_init,
 200         sdb_attr_destroy
 201 };
 202
 203 /*
 204  * private helper functions
 205  */
 206
 207 static sdb_host_t *
 208 lookup_host(const char *name)
 209 {
 210         return HOST(sdb_llist_search_by_name(host_list, name));
 211 } /* lookup_host */
 212
 213 static int
 214 record_backend(sdb_store_obj_t *obj)
 215 {
 216         const sdb_plugin_info_t *info;
 217         char **tmp;
 218         size_t i;
 219
 220         info = sdb_plugin_current();
 221         if (! info)
 222                 return 0;
 223
 224         for (i = 0; i < obj->backends_num; ++i)
 225                 if (!strcasecmp(obj->backends[i], info->plugin_name))
 226                         return 0;
 227
 228         tmp = realloc(obj->backends,
 229                         (obj->backends_num + 1) * sizeof(*obj->backends));
 230         if (! tmp)
 231                 return -1;
 232
 233         obj->backends = tmp;
 234         obj->backends[obj->backends_num] = strdup(info->plugin_name);
 235         if (! obj->backends[obj->backends_num])
 236                 return -1;
 237
 238         ++obj->backends_num;
 239         return 0;
 240 } /* record_backend */
 241
 242 static int
 243 store_obj(sdb_llist_t *parent_list, int type, const char *name,
 244                 sdb_time_t last_update, sdb_store_obj_t **updated_obj)
 245 {
 246         sdb_store_obj_t *old, *new;
 247         int status = 0;
 248
 249         assert(parent_list);
 250
 251         if (last_update <= 0)
 252                 last_update = sdb_gettime();
 253
 254         old = STORE_OBJ(sdb_llist_search_by_name(parent_list, name));
 255         if (old) {
 256                 if (old->last_update >= last_update) {
 257                         sdb_log(SDB_LOG_DEBUG, "store: Cannot update %s '%s' - "
 258                                         "value too old (%"PRIscTIME" < %"PRIscTIME")",
 259                                         SDB_STORE_TYPE_TO_NAME(type), name,
 260                                         last_update, old->last_update);
 261                         /* don't report an error; the object may be updated by multiple
 262                          * backends */
 263                         status = 1;
 264                 }
 265                 else {
 266                         sdb_time_t interval = last_update - old->last_update;
 267                         old->last_update = last_update;
 268                         if (interval) {
 269                                 if (old->interval)
 270                                         old->interval = (sdb_time_t)((0.9 * (double)old->interval)
 271                                                         + (0.1 * (double)interval));
 272                                 else
 273                                         old->interval = interval;
 274                         }
 275                 }
 276
 277                 new = old;
 278         }
 279         else {
 280                 if (type == SDB_ATTRIBUTE) {
 281                         /* the value will be updated by the caller */
 282                         new = STORE_OBJ(sdb_object_create(name, sdb_attribute_type,
 283                                                 type, last_update, NULL));
 284                 }
 285                 else {
 286                         sdb_type_t t;
 287                         t = type == SDB_HOST ? sdb_host_type : sdb_service_type;
 288                         new = STORE_OBJ(sdb_object_create(name, t, type, last_update));
 289                 }
 290
 291                 if (new) {
 292                         status = sdb_llist_insert_sorted(parent_list, SDB_OBJ(new),
 293                                         sdb_object_cmp_by_name);
 294
 295                         /* pass control to the list or destroy in case of an error */
 296                         sdb_object_deref(SDB_OBJ(new));
 297                 }
 298                 else {
 299                         char errbuf[1024];
 300                         sdb_log(SDB_LOG_ERR, "store: Failed to create %s '%s': %s",
 301                                         SDB_STORE_TYPE_TO_NAME(type), name,
 302                                         sdb_strerror(errno, errbuf, sizeof(errbuf)));
 303                         status = -1;
 304                 }
 305         }
 306
 307         if (status < 0)
 308                 return status;
 309         assert(new);
 310
 311         if (updated_obj)
 312                 *updated_obj = new;
 313
 314         if (record_backend(new))
 315                 return -1;
 316         return status;
 317 } /* store_obj */
 318
 319 static int
 320 store_attr(sdb_llist_t *attributes, const char *key, const sdb_data_t *value,
 321                 sdb_time_t last_update)
 322 {
 323         sdb_store_obj_t *attr = NULL;
 324         int status;
 325
 326         status = store_obj(attributes, SDB_ATTRIBUTE, key, last_update, &attr);
 327         if (status < 0)
 328                 return status;
 329
 330         assert(attr);
 331         if (sdb_data_copy(&ATTR(attr)->value, value))
 332                 return -1;
 333         return status;
 334 } /* store_attr */
 335
 336 /* The host_lock has to be acquired before calling this function. */
 337 static sdb_llist_t *
 338 get_host_children(const char *hostname, int type)
 339 {
 340         char *cname = NULL;
 341         sdb_host_t *host;
 342
 343         assert(hostname);
 344         assert((type == SDB_SERVICE) || (type == SDB_ATTRIBUTE));
 345
 346         if (! host_list)
 347                 return NULL;
 348
 349         cname = sdb_plugin_cname(strdup(hostname));
 350         if (! cname) {
 351                 sdb_log(SDB_LOG_ERR, "store: strdup failed");
 352                 return NULL;
 353         }
 354
 355         host = lookup_host(cname);
 356         free(cname);
 357         if (! host)
 358                 return NULL;
 359
 360         if (type == SDB_ATTRIBUTE)
 361                 return host->attributes;
 362         else
 363                 return host->services;
 364 } /* get_host_children */
 365
 366 /*
 367  * store_common_tojson serializes common object attributes to JSON.
 368  *
 369  * The function never returns an error. Rather, an error message will be part
 370  * of the serialized data.
 371  */
 372 static void
 373 store_common_tojson(sdb_store_obj_t *obj, sdb_strbuf_t *buf)
 374 {
 375         char time_str[64];
 376         char interval_str[64];
 377         size_t i;
 378
 379         if (! sdb_strftime(time_str, sizeof(time_str),
 380                                 "%F %T %z", obj->last_update))
 381                 snprintf(time_str, sizeof(time_str), "<error>");
 382         time_str[sizeof(time_str) - 1] = '\0';
 383
 384         if (! sdb_strfinterval(interval_str, sizeof(interval_str),
 385                                 obj->interval))
 386                 snprintf(interval_str, sizeof(interval_str), "<error>");
 387         interval_str[sizeof(interval_str) - 1] = '\0';
 388
 389         sdb_strbuf_append(buf, "\"last_update\": \"%s\", "
 390                         "\"update_interval\": \"%s\", \"backends\": [",
 391                         time_str, interval_str);
 392
 393         for (i = 0; i < obj->backends_num; ++i) {
 394                 sdb_strbuf_append(buf, "\"%s\"", obj->backends[i]);
 395                 if (i < obj->backends_num - 1)
 396                         sdb_strbuf_append(buf, ",");
 397         }
 398         sdb_strbuf_append(buf, "]");
 399 } /* store_common_tojson */
 400
 401 /*
 402  * store_obj_tojson serializes attribute / service objects to JSON.
 403  *
 404  * The function never returns an error. Rather, an error message will be part
 405  * of the serialized data.
 406  */
 407 static void
 408 store_obj_tojson(sdb_llist_t *list, int type, sdb_strbuf_t *buf)
 409 {
 410         sdb_llist_iter_t *iter;
 411
 412         assert((type == SDB_ATTRIBUTE) || (type == SDB_SERVICE));
 413
 414         sdb_strbuf_append(buf, "[");
 415         iter = sdb_llist_get_iter(list);
 416         if (! iter) {
 417                 char errbuf[1024];
 418                 sdb_log(SDB_LOG_ERR, "store: Failed to retrieve %ss: %s\n",
 419                                 SDB_STORE_TYPE_TO_NAME(type),
 420                                 sdb_strerror(errno, errbuf, sizeof(errbuf)));
 421                 sdb_strbuf_append(buf, "{\"error\": \"failed to retrieve %ss: %s\"}",
 422                                 SDB_STORE_TYPE_TO_NAME(type), errbuf);
 423         }
 424
 425         /* has_next returns false if the iterator is NULL */
 426         while (sdb_llist_iter_has_next(iter)) {
 427                 sdb_store_obj_t *sobj = STORE_OBJ(sdb_llist_iter_get_next(iter));
 428                 assert(sobj);
 429                 assert(sobj->type == type);
 430
 431                 sdb_strbuf_append(buf, "{\"name\": \"%s\", ", SDB_OBJ(sobj)->name);
 432                 if (sobj->type == SDB_ATTRIBUTE) {
 433                         char tmp[sdb_data_strlen(&ATTR(sobj)->value) + 1];
 434                         sdb_data_format(&ATTR(sobj)->value, tmp, sizeof(tmp),
 435                                         SDB_DOUBLE_QUOTED);
 436                         sdb_strbuf_append(buf, "\"value\": %s, ", tmp);
 437                 }
 438
 439                 store_common_tojson(sobj, buf);
 440                 sdb_strbuf_append(buf, "}");
 441
 442                 if (sdb_llist_iter_has_next(iter))
 443                         sdb_strbuf_append(buf, ",");
 444         }
 445
 446         sdb_llist_iter_destroy(iter);
 447         sdb_strbuf_append(buf, "]");
 448 } /* store_obj_tojson */
 449
 450 /*
 451  * public API
 452  */
 453
 454 void
 455 sdb_store_clear(void)
 456 {
 457         sdb_llist_destroy(host_list);
 458         host_list = NULL;
 459 } /* sdb_store_clear */
 460
 461 int
 462 sdb_store_host(const char *name, sdb_time_t last_update)
 463 {
 464         char *cname = NULL;
 465         int status = 0;
 466
 467         if (! name)
 468                 return -1;
 469
 470         cname = sdb_plugin_cname(strdup(name));
 471         if (! cname) {
 472                 sdb_log(SDB_LOG_ERR, "store: strdup failed");
 473                 return -1;
 474         }
 475
 476         pthread_rwlock_wrlock(&host_lock);
 477         if (! host_list)
 478                 if (! (host_list = sdb_llist_create()))
 479                         status = -1;
 480
 481         if (! status)
 482                 status = store_obj(host_list, SDB_HOST, cname, last_update, NULL);
 483         pthread_rwlock_unlock(&host_lock);
 484
 485         free(cname);
 486         return status;
 487 } /* sdb_store_host */
 488
 489 _Bool
 490 sdb_store_has_host(const char *name)
 491 {
 492         sdb_host_t *host;
 493
 494         if (! name)
 495                 return NULL;
 496
 497         host = lookup_host(name);
 498         return host != NULL;
 499 } /* sdb_store_has_host */
 500
 501 sdb_store_obj_t *
 502 sdb_store_get_host(const char *name)
 503 {
 504         sdb_host_t *host;
 505
 506         if (! name)
 507                 return NULL;
 508
 509         host = lookup_host(name);
 510         if (! host)
 511                 return NULL;
 512
 513         sdb_object_ref(SDB_OBJ(host));
 514         return STORE_OBJ(host);
 515 } /* sdb_store_get_host */
 516
 517 int
 518 sdb_store_attribute(const char *hostname,
 519                 const char *key, const sdb_data_t *value,
 520                 sdb_time_t last_update)
 521 {
 522         sdb_llist_t *attrs;
 523         int status = 0;
 524
 525         if ((! hostname) || (! key))
 526                 return -1;
 527
 528         pthread_rwlock_wrlock(&host_lock);
 529         attrs = get_host_children(hostname, SDB_ATTRIBUTE);
 530         if (! attrs) {
 531                 sdb_log(SDB_LOG_ERR, "store: Failed to store attribute '%s' - "
 532                                 "host '%s' not found", key, hostname);
 533                 status = -1;
 534         }
 535
 536         if (! status)
 537                 status = store_attr(attrs, key, value, last_update);
 538
 539         pthread_rwlock_unlock(&host_lock);
 540         return status;
 541 } /* sdb_store_attribute */
 542
 543 int
 544 sdb_store_service(const char *hostname, const char *name,
 545                 sdb_time_t last_update)
 546 {
 547         sdb_llist_t *services;
 548
 549         int status = 0;
 550
 551         if ((! hostname) || (! name))
 552                 return -1;
 553
 554         pthread_rwlock_wrlock(&host_lock);
 555         services = get_host_children(hostname, SDB_SERVICE);
 556         if (! services) {
 557                 sdb_log(SDB_LOG_ERR, "store: Failed to store service '%s' - "
 558                                 "host '%s' not found", name, hostname);
 559                 status = -1;
 560         }
 561
 562         if (! status)
 563                 status = store_obj(services, SDB_SERVICE, name, last_update, NULL);
 564         pthread_rwlock_unlock(&host_lock);
 565         return status;
 566 } /* sdb_store_service */
 567
 568 int
 569 sdb_store_service_attr(const char *hostname, const char *service,
 570                 const char *key, const sdb_data_t *value, sdb_time_t last_update)
 571 {
 572         sdb_llist_t *services;
 573         sdb_service_t *svc;
 574         int status = 0;
 575
 576         if ((! hostname) || (! service) || (! key))
 577                 return -1;
 578
 579         pthread_rwlock_wrlock(&host_lock);
 580         services = get_host_children(hostname, SDB_SERVICE);
 581         if (! services) {
 582                 sdb_log(SDB_LOG_ERR, "store: Failed to store attribute '%s' "
 583                                 "for service '%s' - host '%ss' not found",
 584                                 key, service, hostname);
 585                 pthread_rwlock_unlock(&host_lock);
 586                 return -1;
 587         }
 588
 589         svc = SVC(sdb_llist_search_by_name(services, service));
 590         if (! svc) {
 591                 sdb_log(SDB_LOG_ERR, "store: Failed to store attribute '%s' - "
 592                                 "service '%s/%s' not found", key, hostname, service);
 593                 status = -1;
 594         }
 595
 596         if (! status)
 597                 status = store_attr(svc->attributes, key, value, last_update);
 598
 599         pthread_rwlock_unlock(&host_lock);
 600         return status;
 601 } /* sdb_store_service_attr */
 602
 603 int
 604 sdb_store_host_tojson(sdb_store_obj_t *h, sdb_strbuf_t *buf, int flags)
 605 {
 606         sdb_host_t *host;
 607
 608         if ((! h) || (h->type != SDB_HOST) || (! buf))
 609                 return -1;
 610
 611         host = HOST(h);
 612
 613         sdb_strbuf_append(buf, "{\"name\": \"%s\", ", SDB_OBJ(host)->name);
 614         store_common_tojson(h, buf);
 615
 616         if (! (flags & SDB_SKIP_ATTRIBUTES)) {
 617                 sdb_strbuf_append(buf, ", \"attributes\": ");
 618                 store_obj_tojson(host->attributes, SDB_ATTRIBUTE, buf);
 619         }
 620
 621         if (! (flags & SDB_SKIP_SERVICES)) {
 622                 sdb_strbuf_append(buf, ", \"services\": ");
 623                 store_obj_tojson(host->services, SDB_SERVICE, buf);
 624         }
 625
 626         sdb_strbuf_append(buf, "}");
 627         return 0;
 628 } /* sdb_store_host_tojson */
 629
 630 int
 631 sdb_store_tojson(sdb_strbuf_t *buf, int flags)
 632 {
 633         sdb_llist_iter_t *host_iter;
 634
 635         if (! buf)
 636                 return -1;
 637
 638         pthread_rwlock_rdlock(&host_lock);
 639
 640         host_iter = sdb_llist_get_iter(host_list);
 641         if (! host_iter) {
 642                 pthread_rwlock_unlock(&host_lock);
 643                 return -1;
 644         }
 645
 646         sdb_strbuf_append(buf, "{\"hosts\":[");
 647
 648         while (sdb_llist_iter_has_next(host_iter)) {
 649                 sdb_store_obj_t *host = STORE_OBJ(sdb_llist_iter_get_next(host_iter));
 650                 assert(host);
 651
 652                 if (sdb_store_host_tojson(host, buf, flags))
 653                         return -1;
 654
 655                 if (sdb_llist_iter_has_next(host_iter))
 656                         sdb_strbuf_append(buf, ",");
 657         }
 658
 659         sdb_strbuf_append(buf, "]}");
 660
 661         sdb_llist_iter_destroy(host_iter);
 662         pthread_rwlock_unlock(&host_lock);
 663         return 0;
 664 } /* sdb_store_tojson */
 665
 666 /* TODO: actually support hierarchical data */
 667 int
 668 sdb_store_iterate(sdb_store_iter_cb cb, void *user_data)
 669 {
 670         sdb_llist_iter_t *host_iter;
 671         int status = 0;
 672
 673         pthread_rwlock_rdlock(&host_lock);
 674
 675         host_iter = sdb_llist_get_iter(host_list);
 676         if (! host_iter)
 677                 status = -1;
 678
 679         /* has_next returns false if the iterator is NULL */
 680         while (sdb_llist_iter_has_next(host_iter)) {
 681                 sdb_store_obj_t *host = STORE_OBJ(sdb_llist_iter_get_next(host_iter));
 682                 assert(host);
 683
 684                 if (cb(host, user_data)) {
 685                         status = -1;
 686                         break;
 687                 }
 688         }
 689
 690         sdb_llist_iter_destroy(host_iter);
 691         pthread_rwlock_unlock(&host_lock);
 692         return status;
 693 } /* sdb_store_iterate */
 694
 695 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 696