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_obj_tojson serializes attribute / service objects 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_obj_tojson(sdb_llist_t *list, int type, sdb_strbuf_t *buf)
 345 {
 346         sdb_llist_iter_t *iter;
 347         char time_str[64];
 348         char interval_str[64];
 349
 350         assert((type == SDB_ATTRIBUTE) || (type == SDB_SERVICE));
 351
 352         sdb_strbuf_append(buf, "[");
 353
 354         iter = sdb_llist_get_iter(list);
 355         if (! iter) {
 356                 char errbuf[1024];
 357                 sdb_log(SDB_LOG_ERR, "store: Failed to retrieve %ss: %s\n",
 358                                 SDB_STORE_TYPE_TO_NAME(type),
 359                                 sdb_strerror(errno, errbuf, sizeof(errbuf)));
 360                 sdb_strbuf_append(buf, "{\"error\": \"failed to retrieve %ss: %s\"}",
 361                                 SDB_STORE_TYPE_TO_NAME(type), errbuf);
 362         }
 363
 364         /* has_next returns false if the iterator is NULL */
 365         while (sdb_llist_iter_has_next(iter)) {
 366                 sdb_store_obj_t *sobj = STORE_OBJ(sdb_llist_iter_get_next(iter));
 367                 assert(sobj);
 368                 assert(sobj->type == type);
 369
 370                 if (! sdb_strftime(time_str, sizeof(time_str),
 371                                         "%F %T %z", sobj->last_update))
 372                         snprintf(time_str, sizeof(time_str), "<error>");
 373                 time_str[sizeof(time_str) - 1] = '\0';
 374
 375                 if (! sdb_strfinterval(interval_str, sizeof(interval_str),
 376                                         sobj->interval))
 377                         snprintf(interval_str, sizeof(interval_str), "<error>");
 378                 interval_str[sizeof(interval_str) - 1] = '\0';
 379
 380                 sdb_strbuf_append(buf, "{\"name\": \"%s\", ", SDB_OBJ(sobj)->name);
 381                 if (sobj->type == SDB_ATTRIBUTE) {
 382                         char tmp[sdb_data_strlen(&ATTR(sobj)->value) + 1];
 383                         sdb_data_format(&ATTR(sobj)->value, tmp, sizeof(tmp),
 384                                         SDB_DOUBLE_QUOTED);
 385                         sdb_strbuf_append(buf, "\"value\": %s, \"last_update\": \"%s\", "
 386                                         "\"update_interval\": \"%s\"}", tmp, time_str,
 387                                         interval_str);
 388                 }
 389                 else
 390                         sdb_strbuf_append(buf, "\"last_update\": \"%s\", "
 391                                         "\"update_interval\": \"%s\"}", time_str, interval_str);
 392
 393                 if (sdb_llist_iter_has_next(iter))
 394                         sdb_strbuf_append(buf, ",");
 395         }
 396
 397         sdb_llist_iter_destroy(iter);
 398         sdb_strbuf_append(buf, "]");
 399 } /* store_obj_tojson */
 400
 401 /*
 402  * public API
 403  */
 404
 405 void
 406 sdb_store_clear(void)
 407 {
 408         sdb_llist_destroy(host_list);
 409         host_list = NULL;
 410 } /* sdb_store_clear */
 411
 412 int
 413 sdb_store_host(const char *name, sdb_time_t last_update)
 414 {
 415         int status;
 416
 417         if (! name)
 418                 return -1;
 419
 420         pthread_rwlock_wrlock(&host_lock);
 421         status = store_obj(/* hostname = */ NULL,
 422                         /* stored object = */ SDB_HOST, name, last_update,
 423                         /* updated_obj = */ NULL);
 424         pthread_rwlock_unlock(&host_lock);
 425         return status;
 426 } /* sdb_store_host */
 427
 428 _Bool
 429 sdb_store_has_host(const char *name)
 430 {
 431         sdb_host_t *host;
 432
 433         if (! name)
 434                 return NULL;
 435
 436         host = lookup_host(name);
 437         return host != NULL;
 438 } /* sdb_store_has_host */
 439
 440 sdb_store_obj_t *
 441 sdb_store_get_host(const char *name)
 442 {
 443         sdb_host_t *host;
 444
 445         if (! name)
 446                 return NULL;
 447
 448         host = lookup_host(name);
 449         if (! host)
 450                 return NULL;
 451
 452         sdb_object_ref(SDB_OBJ(host));
 453         return STORE_OBJ(host);
 454 } /* sdb_store_get_host */
 455
 456 int
 457 sdb_store_attribute(const char *hostname,
 458                 const char *key, const sdb_data_t *value,
 459                 sdb_time_t last_update)
 460 {
 461         int status;
 462
 463         sdb_store_obj_t *updated_attr = NULL;
 464
 465         if ((! hostname) || (! key))
 466                 return -1;
 467
 468         pthread_rwlock_wrlock(&host_lock);
 469         status = store_obj(hostname,
 470                         /* stored object = */ SDB_ATTRIBUTE, key, last_update,
 471                         &updated_attr);
 472
 473         if (status >= 0) {
 474                 assert(updated_attr);
 475                 sdb_data_free_datum(&ATTR(updated_attr)->value);
 476                 if (sdb_data_copy(&ATTR(updated_attr)->value, value)) {
 477                         sdb_object_deref(SDB_OBJ(updated_attr));
 478                         status = -1;
 479                 }
 480         }
 481
 482         pthread_rwlock_unlock(&host_lock);
 483         return status;
 484 } /* sdb_store_attribute */
 485
 486 int
 487 sdb_store_service(const char *hostname, const char *name,
 488                 sdb_time_t last_update)
 489 {
 490         int status;
 491
 492         if ((! hostname) || (! name))
 493                 return -1;
 494
 495         pthread_rwlock_wrlock(&host_lock);
 496         status = store_obj(hostname,
 497                         /* stored object = */ SDB_SERVICE, name, last_update,
 498                         /* updated obj = */ NULL);
 499         pthread_rwlock_unlock(&host_lock);
 500         return status;
 501 } /* sdb_store_service */
 502
 503 int
 504 sdb_store_host_tojson(sdb_store_obj_t *h, sdb_strbuf_t *buf, int flags)
 505 {
 506         sdb_host_t *host;
 507         char time_str[64];
 508         char interval_str[64];
 509
 510         if ((! h) || (h->type != SDB_HOST) || (! buf))
 511                 return -1;
 512
 513         host = HOST(h);
 514
 515         if (! sdb_strftime(time_str, sizeof(time_str),
 516                                 "%F %T %z", host->_last_update))
 517                 snprintf(time_str, sizeof(time_str), "<error>");
 518         time_str[sizeof(time_str) - 1] = '\0';
 519
 520         if (! sdb_strfinterval(interval_str, sizeof(interval_str),
 521                                 host->_interval))
 522                 snprintf(interval_str, sizeof(interval_str), "<error>");
 523         interval_str[sizeof(interval_str) - 1] = '\0';
 524
 525         sdb_strbuf_append(buf, "{\"name\": \"%s\", "
 526                         "\"last_update\": \"%s\", \"update_interval\": \"%s\"",
 527                         SDB_OBJ(host)->name, time_str, interval_str);
 528
 529         if (! (flags & SDB_SKIP_ATTRIBUTES)) {
 530                 sdb_strbuf_append(buf, ", \"attributes\": ");
 531                 store_obj_tojson(host->attributes, SDB_ATTRIBUTE, buf);
 532         }
 533
 534         if (! (flags & SDB_SKIP_SERVICES)) {
 535                 sdb_strbuf_append(buf, ", \"services\": ");
 536                 store_obj_tojson(host->services, SDB_SERVICE, buf);
 537         }
 538
 539         sdb_strbuf_append(buf, "}");
 540         return 0;
 541 } /* sdb_store_host_tojson */
 542
 543 int
 544 sdb_store_tojson(sdb_strbuf_t *buf, int flags)
 545 {
 546         sdb_llist_iter_t *host_iter;
 547
 548         if (! buf)
 549                 return -1;
 550
 551         pthread_rwlock_rdlock(&host_lock);
 552
 553         host_iter = sdb_llist_get_iter(host_list);
 554         if (! host_iter) {
 555                 pthread_rwlock_unlock(&host_lock);
 556                 return -1;
 557         }
 558
 559         sdb_strbuf_append(buf, "{\"hosts\":[");
 560
 561         while (sdb_llist_iter_has_next(host_iter)) {
 562                 sdb_store_obj_t *host = STORE_OBJ(sdb_llist_iter_get_next(host_iter));
 563                 assert(host);
 564
 565                 if (sdb_store_host_tojson(host, buf, flags))
 566                         return -1;
 567
 568                 if (sdb_llist_iter_has_next(host_iter))
 569                         sdb_strbuf_append(buf, ",");
 570         }
 571
 572         sdb_strbuf_append(buf, "]}");
 573
 574         sdb_llist_iter_destroy(host_iter);
 575         pthread_rwlock_unlock(&host_lock);
 576         return 0;
 577 } /* sdb_store_tojson */
 578
 579 /* TODO: actually support hierarchical data */
 580 int
 581 sdb_store_iterate(sdb_store_iter_cb cb, void *user_data)
 582 {
 583         sdb_llist_iter_t *host_iter;
 584         int status = 0;
 585
 586         pthread_rwlock_rdlock(&host_lock);
 587
 588         host_iter = sdb_llist_get_iter(host_list);
 589         if (! host_iter)
 590                 status = -1;
 591
 592         /* has_next returns false if the iterator is NULL */
 593         while (sdb_llist_iter_has_next(host_iter)) {
 594                 sdb_store_obj_t *host = STORE_OBJ(sdb_llist_iter_get_next(host_iter));
 595                 assert(host);
 596
 597                 if (cb(host, user_data)) {
 598                         status = -1;
 599                         break;
 600                 }
 601         }
 602
 603         sdb_llist_iter_destroy(host_iter);
 604         pthread_rwlock_unlock(&host_lock);
 605         return status;
 606 } /* sdb_store_iterate */
 607
 608 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 609