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 #include "sysdb.h"
  29 #include "core/store.h"
  30 #include "core/plugin.h"
  31 #include "utils/error.h"
  32 #include "utils/llist.h"
  33
  34 #include <assert.h>
  35
  36 #include <errno.h>
  37
  38 #include <stdio.h>
  39 #include <stdlib.h>
  40 #include <string.h>
  41
  42 #include <pthread.h>
  43
  44 /*
  45  * private variables
  46  */
  47
  48 static sdb_llist_t *obj_list = NULL;
  49 static pthread_rwlock_t obj_lock = PTHREAD_RWLOCK_INITIALIZER;
  50
  51 /*
  52  * private types
  53  */
  54
  55 static sdb_type_t sdb_store_obj_type;
  56 static sdb_type_t sdb_attribute_type;
  57
  58 struct sdb_store_base {
  59         sdb_object_t super;
  60
  61         /* object type */
  62         int type;
  63
  64         /* common meta information */
  65         sdb_time_t last_update;
  66         sdb_store_base_t *parent;
  67 };
  68 #define STORE_BASE(obj) ((sdb_store_base_t *)(obj))
  69 #define STORE_CONST_BASE(obj) ((const sdb_store_base_t *)(obj))
  70
  71 typedef struct {
  72         sdb_store_base_t super;
  73
  74         sdb_data_t value;
  75 } sdb_attribute_t;
  76 #define SDB_ATTR(obj) ((sdb_attribute_t *)(obj))
  77 #define SDB_CONST_ATTR(obj) ((const sdb_attribute_t *)(obj))
  78
  79 typedef struct {
  80         sdb_store_base_t super;
  81
  82         sdb_llist_t *children;
  83         sdb_llist_t *attributes;
  84 } sdb_store_obj_t;
  85 #define SDB_STORE_OBJ(obj) ((sdb_store_obj_t *)(obj))
  86 #define SDB_CONST_STORE_OBJ(obj) ((const sdb_store_obj_t *)(obj))
  87
  88 enum {
  89         SDB_HOST = 1,
  90         SDB_SERVICE,
  91         SDB_ATTRIBUTE,
  92 };
  93 #define TYPE_TO_NAME(t) \
  94         (((t) == SDB_HOST) ? "host" \
  95                 : ((t) == SDB_SERVICE) ? "service" \
  96                 : ((t) == SDB_ATTRIBUTE) ? "attribute" : "unknown")
  97
  98 /* shortcuts for accessing the sdb_store_obj_t attributes
  99  * of inheriting objects */
 100 #define _last_update super.last_update
 101
 102 static int
 103 store_base_init(sdb_object_t *obj, va_list ap)
 104 {
 105         sdb_store_base_t *sobj = STORE_BASE(obj);
 106
 107         sobj->type = va_arg(ap, int);
 108
 109         sobj->last_update = va_arg(ap, sdb_time_t);
 110         sobj->parent = NULL;
 111         return 0;
 112 } /* store_base_init */
 113
 114 static void
 115 store_base_destroy(sdb_object_t *obj)
 116 {
 117         const sdb_store_base_t *sobj = STORE_CONST_BASE(obj);
 118
 119         if (sobj->parent)
 120                 sdb_object_deref(SDB_OBJ(sobj->parent));
 121 } /* store_base_destroy */
 122
 123 static int
 124 sdb_store_obj_init(sdb_object_t *obj, va_list ap)
 125 {
 126         sdb_store_obj_t *sobj = SDB_STORE_OBJ(obj);
 127         int ret;
 128
 129         /* this will consume the first argument (type) of ap */
 130         ret = store_base_init(obj, ap);
 131         if (ret)
 132                 return ret;
 133
 134         sobj->children = sdb_llist_create();
 135         if (! sobj->children)
 136                 return -1;
 137         sobj->attributes = sdb_llist_create();
 138         if (! sobj->attributes)
 139                 return -1;
 140         return 0;
 141 } /* sdb_store_obj_init */
 142
 143 static void
 144 sdb_store_obj_destroy(sdb_object_t *obj)
 145 {
 146         sdb_store_obj_t *sobj = SDB_STORE_OBJ(obj);
 147
 148         assert(obj);
 149
 150         store_base_destroy(obj);
 151
 152         if (sobj->children)
 153                 sdb_llist_destroy(sobj->children);
 154         if (sobj->attributes)
 155                 sdb_llist_destroy(sobj->attributes);
 156 } /* sdb_store_obj_destroy */
 157
 158 static int
 159 sdb_attr_init(sdb_object_t *obj, va_list ap)
 160 {
 161         const sdb_data_t *value;
 162         int ret;
 163
 164         /* this will consume the first two arguments
 165          * (type and last_update) of ap */
 166         ret = store_base_init(obj, ap);
 167         if (ret)
 168                 return ret;
 169         value = va_arg(ap, const sdb_data_t *);
 170
 171         if (value)
 172                 if (sdb_data_copy(&SDB_ATTR(obj)->value, value))
 173                         return -1;
 174         return 0;
 175 } /* sdb_attr_init */
 176
 177 static void
 178 sdb_attr_destroy(sdb_object_t *obj)
 179 {
 180         assert(obj);
 181
 182         store_base_destroy(obj);
 183         sdb_data_free_datum(&SDB_ATTR(obj)->value);
 184 } /* sdb_attr_destroy */
 185
 186 static sdb_type_t sdb_store_obj_type = {
 187         sizeof(sdb_store_obj_t),
 188
 189         sdb_store_obj_init,
 190         sdb_store_obj_destroy
 191 };
 192
 193 static sdb_type_t sdb_attribute_type = {
 194         sizeof(sdb_attribute_t),
 195
 196         sdb_attr_init,
 197         sdb_attr_destroy
 198 };
 199
 200 /*
 201  * private helper functions
 202  */
 203
 204 static sdb_store_obj_t *
 205 store_lookup_in_list(sdb_llist_t *l, int type, const char *name)
 206 {
 207         sdb_llist_iter_t *iter;
 208
 209         if (! l)
 210                 return NULL;
 211
 212         iter = sdb_llist_get_iter(l);
 213         if (! iter)
 214                 return NULL;
 215
 216         while (sdb_llist_iter_has_next(iter)) {
 217                 sdb_store_obj_t *sobj = SDB_STORE_OBJ(sdb_llist_iter_get_next(iter));
 218                 assert(sobj);
 219
 220                 if ((STORE_BASE(sobj)->type == type)
 221                                 && (! strcasecmp(SDB_OBJ(sobj)->name, name))) {
 222                         sdb_llist_iter_destroy(iter);
 223                         return sobj;
 224                 }
 225
 226                 /* don't lookups non-host types from hierarchical hosts */
 227                 if ((type != SDB_HOST) && (STORE_BASE(sobj)->type == SDB_HOST))
 228                         continue;
 229
 230                 sobj = store_lookup_in_list(sobj->children, type, name);
 231                 if (sobj) {
 232                         sdb_llist_iter_destroy(iter);
 233                         return sobj;
 234                 }
 235         }
 236         sdb_llist_iter_destroy(iter);
 237         return NULL;
 238 } /* store_lookup_in_list */
 239
 240 static sdb_store_obj_t *
 241 store_lookup(int type, const char *name)
 242 {
 243         return store_lookup_in_list(obj_list, type, name);
 244 } /* store_lookup */
 245
 246 /* The obj_lock has to be acquired before calling this function. */
 247 static int
 248 store_obj(int parent_type, const char *parent_name,
 249                 int type, const char *name, sdb_time_t last_update,
 250                 sdb_store_base_t **updated_obj)
 251 {
 252         char *parent_cname = NULL, *cname = NULL;
 253
 254         sdb_llist_t *parent_list;
 255         sdb_store_base_t *old;
 256         int status = 0;
 257
 258         if (last_update <= 0)
 259                 last_update = sdb_gettime();
 260
 261         assert((parent_type == 0)
 262                         || (parent_type == SDB_HOST)
 263                         || (parent_type == SDB_SERVICE));
 264         assert((type == 0)
 265                         || (type == SDB_HOST)
 266                         || (type == SDB_SERVICE)
 267                         || (type == SDB_ATTRIBUTE));
 268
 269         if (parent_type == SDB_HOST) {
 270                 parent_cname = sdb_plugin_cname(strdup(parent_name));
 271                 if (! parent_cname) {
 272                         sdb_log(SDB_LOG_ERR, "store: strdup failed");
 273                         return -1;
 274                 }
 275                 parent_name = parent_cname;
 276         }
 277         if (type == SDB_HOST) {
 278                 cname = sdb_plugin_cname(strdup(name));
 279                 if (! cname) {
 280                         sdb_log(SDB_LOG_ERR, "store: strdup failed");
 281                         return -1;
 282                 }
 283                 name = cname;
 284         }
 285
 286         if (! obj_list) {
 287                 if (! (obj_list = sdb_llist_create())) {
 288                         free(parent_cname);
 289                         free(cname);
 290                         return -1;
 291                 }
 292         }
 293         parent_list = obj_list;
 294
 295         if (parent_type && parent_name) {
 296                 sdb_store_obj_t *parent;
 297
 298                 parent = store_lookup(parent_type, parent_name);
 299                 if (! parent) {
 300                         sdb_log(SDB_LOG_ERR, "store: Failed to store %s '%s' - "
 301                                         "parent %s '%s' not found", TYPE_TO_NAME(type), name,
 302                                         TYPE_TO_NAME(parent_type), parent_name);
 303                         free(parent_cname);
 304                         free(cname);
 305                         return -1;
 306                 }
 307
 308                 if (type == SDB_ATTRIBUTE)
 309                         parent_list = parent->attributes;
 310                 else
 311                         parent_list = parent->children;
 312         }
 313
 314         if (type == SDB_HOST)
 315                 /* make sure that each host is unique */
 316                 old = STORE_BASE(store_lookup_in_list(obj_list, type, name));
 317         else if (type == SDB_ATTRIBUTE)
 318                 /* look into attributes of this host */
 319                 old = STORE_BASE(sdb_llist_search_by_name(parent_list, name));
 320         else
 321                 /* look into services assigned to this host (store_lookup_in_list
 322                  * does not look up services from hierarchical hosts) */
 323                 old = STORE_BASE(store_lookup_in_list(parent_list, type, name));
 324
 325         if (old) {
 326                 if (old->last_update > last_update) {
 327                         sdb_log(SDB_LOG_DEBUG, "store: Cannot update %s '%s' - "
 328                                         "value too old (%"PRIscTIME" < %"PRIscTIME")",
 329                                         TYPE_TO_NAME(type), name, last_update, old->last_update);
 330                         /* don't report an error; the object may be updated by multiple
 331                          * backends */
 332                         status = 1;
 333                 }
 334                 else {
 335                         old->last_update = last_update;
 336                 }
 337
 338                 if (updated_obj)
 339                         *updated_obj = old;
 340         }
 341         else {
 342                 sdb_store_base_t *new;
 343
 344                 if (type == SDB_ATTRIBUTE)
 345                         /* the value will be updated by the caller */
 346                         new = STORE_BASE(sdb_object_create(name, sdb_attribute_type,
 347                                                 type, last_update, NULL));
 348                 else
 349                         new = STORE_BASE(sdb_object_create(name, sdb_store_obj_type,
 350                                                 type, last_update));
 351
 352                 if (! new) {
 353                         char errbuf[1024];
 354                         sdb_log(SDB_LOG_ERR, "store: Failed to create %s '%s': %s",
 355                                         TYPE_TO_NAME(type), name,
 356                                         sdb_strerror(errno, errbuf, sizeof(errbuf)));
 357                         free(parent_cname);
 358                         free(cname);
 359                         return -1;
 360                 }
 361
 362                 /* TODO: insert type-aware; the current version works as long as we
 363                  * don't support to store hierarchical data */
 364                 status = sdb_llist_insert_sorted(parent_list, SDB_OBJ(new),
 365                                 sdb_object_cmp_by_name);
 366
 367                 /* pass control to the list or destroy in case of an error */
 368                 sdb_object_deref(SDB_OBJ(new));
 369
 370                 if (updated_obj)
 371                         *updated_obj = new;
 372         }
 373         free(parent_cname);
 374         free(cname);
 375         return status;
 376 } /* store_obj */
 377
 378 /*
 379  * store_obj_tojson serializes attribute / service objects to JSON.
 380  *
 381  * The function never returns an error. Rather, an error message will be part
 382  * of the serialized data.
 383  */
 384 static void
 385 store_obj_tojson(sdb_llist_t *list, int type, sdb_strbuf_t *buf)
 386 {
 387         sdb_llist_iter_t *iter;
 388         char time_str[64];
 389
 390         assert((type == SDB_ATTRIBUTE) || (type == SDB_SERVICE));
 391
 392         sdb_strbuf_append(buf, "[");
 393
 394         iter = sdb_llist_get_iter(list);
 395         if (! iter) {
 396                 char errbuf[1024];
 397                 sdb_log(SDB_LOG_ERR, "store: Failed to retrieve %ss: %s\n",
 398                                 TYPE_TO_NAME(type),
 399                                 sdb_strerror(errno, errbuf, sizeof(errbuf)));
 400                 sdb_strbuf_append(buf, "{\"error\": \"failed to retrieve %ss: %s\"}",
 401                                 TYPE_TO_NAME(type), errbuf);
 402         }
 403
 404         /* has_next returns false if the iterator is NULL */
 405         while (sdb_llist_iter_has_next(iter)) {
 406                 sdb_store_base_t *sobj = STORE_BASE(sdb_llist_iter_get_next(iter));
 407                 assert(sobj);
 408
 409                 if (! sdb_strftime(time_str, sizeof(time_str),
 410                                         "%F %T %z", sobj->last_update))
 411                         snprintf(time_str, sizeof(time_str), "<error>");
 412                 time_str[sizeof(time_str) - 1] = '\0';
 413
 414                 sdb_strbuf_append(buf, "{\"name\": \"%s\", ", SDB_OBJ(sobj)->name);
 415                 if (type == SDB_ATTRIBUTE) {
 416                         sdb_strbuf_append(buf, "\"value\": ");
 417                         sdb_data_format(&SDB_ATTR(sobj)->value, buf);
 418                         sdb_strbuf_append(buf, ", \"last_update\": \"%s\"}", time_str);
 419                 }
 420                 else
 421                         sdb_strbuf_append(buf, "\"last_update\": \"%s\"}", time_str);
 422
 423                 if (sdb_llist_iter_has_next(iter))
 424                         sdb_strbuf_append(buf, ",");
 425         }
 426
 427         sdb_llist_iter_destroy(iter);
 428         sdb_strbuf_append(buf, "]");
 429 } /* store_obj_tojson */
 430
 431 /*
 432  * public API
 433  */
 434
 435 int
 436 sdb_store_host(const char *name, sdb_time_t last_update)
 437 {
 438         int status;
 439
 440         if (! name)
 441                 return -1;
 442
 443         pthread_rwlock_wrlock(&obj_lock);
 444         status = store_obj(/* parent = */ 0, NULL,
 445                         /* stored object = */ SDB_HOST, name, last_update,
 446                         /* updated_obj = */ NULL);
 447         pthread_rwlock_unlock(&obj_lock);
 448         return status;
 449 } /* sdb_store_host */
 450
 451 _Bool
 452 sdb_store_has_host(const char *name)
 453 {
 454         sdb_store_obj_t *host;
 455
 456         if (! name)
 457                 return NULL;
 458
 459         host = store_lookup(SDB_HOST, name);
 460         return host != NULL;
 461 } /* sdb_store_has_host */
 462
 463 sdb_store_base_t *
 464 sdb_store_get_host(const char *name)
 465 {
 466         sdb_store_obj_t *host;
 467
 468         if (! name)
 469                 return NULL;
 470
 471         host = store_lookup(SDB_HOST, name);
 472         if (! host)
 473                 return NULL;
 474
 475         sdb_object_ref(SDB_OBJ(host));
 476         return STORE_BASE(host);
 477 } /* sdb_store_get_host */
 478
 479 int
 480 sdb_store_attribute(const char *hostname,
 481                 const char *key, const sdb_data_t *value,
 482                 sdb_time_t last_update)
 483 {
 484         int status;
 485
 486         sdb_store_base_t *updated_attr = NULL;
 487
 488         if ((! hostname) || (! key))
 489                 return -1;
 490
 491         pthread_rwlock_wrlock(&obj_lock);
 492         status = store_obj(/* parent = */ SDB_HOST, hostname,
 493                         /* stored object = */ SDB_ATTRIBUTE, key, last_update,
 494                         &updated_attr);
 495
 496         if (status >= 0) {
 497                 assert(updated_attr);
 498                 if (sdb_data_copy(&SDB_ATTR(updated_attr)->value, value)) {
 499                         sdb_object_deref(SDB_OBJ(updated_attr));
 500                         status = -1;
 501                 }
 502         }
 503
 504         pthread_rwlock_unlock(&obj_lock);
 505         return status;
 506 } /* sdb_store_attribute */
 507
 508 int
 509 sdb_store_service(const char *hostname, const char *name,
 510                 sdb_time_t last_update)
 511 {
 512         int status;
 513
 514         if ((! hostname) || (! name))
 515                 return -1;
 516
 517         pthread_rwlock_wrlock(&obj_lock);
 518         status = store_obj(/* parent = */ SDB_HOST, hostname,
 519                         /* stored object = */ SDB_SERVICE, name, last_update,
 520                         /* updated obj = */ NULL);
 521         pthread_rwlock_unlock(&obj_lock);
 522         return status;
 523 } /* sdb_store_service */
 524
 525 int
 526 sdb_store_host_tojson(sdb_store_base_t *h, sdb_strbuf_t *buf, int flags)
 527 {
 528         sdb_store_obj_t *host;
 529         char time_str[64];
 530
 531         if ((! h) || (h->type != SDB_HOST) || (! buf))
 532                 return -1;
 533
 534         host = SDB_STORE_OBJ(h);
 535
 536         if (! sdb_strftime(time_str, sizeof(time_str),
 537                                 "%F %T %z", host->_last_update))
 538                 snprintf(time_str, sizeof(time_str), "<error>");
 539         time_str[sizeof(time_str) - 1] = '\0';
 540
 541         sdb_strbuf_append(buf, "{\"name\": \"%s\", "
 542                         "\"last_update\": \"%s\"",
 543                         SDB_OBJ(host)->name, time_str);
 544
 545         if (! (flags & SDB_SKIP_ATTRIBUTES)) {
 546                 sdb_strbuf_append(buf, ", \"attributes\": ");
 547                 store_obj_tojson(host->attributes, SDB_ATTRIBUTE, buf);
 548         }
 549
 550         if (! (flags & SDB_SKIP_SERVICES)) {
 551                 sdb_strbuf_append(buf, ", \"services\": ");
 552                 store_obj_tojson(host->children, SDB_SERVICE, buf);
 553         }
 554
 555         sdb_strbuf_append(buf, "}");
 556         return 0;
 557 } /* sdb_store_host_tojson */
 558
 559 /* TODO: actually support hierarchical data */
 560 int
 561 sdb_store_tojson(sdb_strbuf_t *buf, int flags)
 562 {
 563         sdb_llist_iter_t *host_iter;
 564
 565         if (! buf)
 566                 return -1;
 567
 568         pthread_rwlock_rdlock(&obj_lock);
 569
 570         host_iter = sdb_llist_get_iter(obj_list);
 571         if (! host_iter) {
 572                 pthread_rwlock_unlock(&obj_lock);
 573                 return -1;
 574         }
 575
 576         sdb_strbuf_append(buf, "{\"hosts\":[");
 577
 578         while (sdb_llist_iter_has_next(host_iter)) {
 579                 sdb_store_base_t *host = STORE_BASE(sdb_llist_iter_get_next(host_iter));
 580                 assert(host);
 581
 582                 if (sdb_store_host_tojson(host, buf, flags))
 583                         return -1;
 584
 585                 if (sdb_llist_iter_has_next(host_iter))
 586                         sdb_strbuf_append(buf, ",");
 587         }
 588
 589         sdb_strbuf_append(buf, "]}");
 590
 591         sdb_llist_iter_destroy(host_iter);
 592         pthread_rwlock_unlock(&obj_lock);
 593         return 0;
 594 } /* sdb_store_tojson */
 595
 596 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 597