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