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