src/core/store.c

   1 /*
   2  * SysDB - src/core/store.c
   3  * Copyright (C) 2012 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/error.h"
  31 #include "core/plugin.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 store_obj;
  59 typedef struct store_obj store_obj_t;
  60
  61 struct store_obj {
  62         sdb_object_t super;
  63         sdb_time_t last_update;
  64         store_obj_t *parent;
  65 };
  66 #define STORE_OBJ(obj) ((store_obj_t *)(obj))
  67 #define STORE_CONST_OBJ(obj) ((const store_obj_t *)(obj))
  68
  69 typedef struct {
  70         store_obj_t super;
  71
  72         char *value;
  73 } sdb_attribute_t;
  74 #define SDB_ATTR(obj) ((sdb_attribute_t *)(obj))
  75 #define SDB_CONST_ATTR(obj) ((const sdb_attribute_t *)(obj))
  76
  77 typedef struct {
  78         store_obj_t super;
  79
  80         int type;
  81         sdb_llist_t *children;
  82
  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_obj_init(sdb_object_t *obj, va_list ap)
 104 {
 105         store_obj_t *sobj = STORE_OBJ(obj);
 106         sobj->last_update = va_arg(ap, sdb_time_t);
 107
 108         sobj->parent = NULL;
 109         return 0;
 110 } /* store_obj_init */
 111
 112 static void
 113 store_obj_destroy(sdb_object_t *obj)
 114 {
 115         const store_obj_t *sobj = STORE_OBJ(obj);
 116
 117         if (sobj->parent)
 118                 sdb_object_deref(SDB_OBJ(sobj->parent));
 119 } /* store_obj_destroy */
 120
 121 /* this may not be used as a type on its own but only as helper functions for
 122  * the derived types; the function accepts a variadic list of arguments to
 123  * pass to the sub-type's init function */
 124 static sdb_object_t *
 125 store_obj_clone(const sdb_object_t *obj, ...)
 126 {
 127         const store_obj_t *sobj = STORE_CONST_OBJ(obj);
 128         store_obj_t *new;
 129
 130         va_list ap;
 131
 132         va_start(ap, obj);
 133
 134         new = STORE_OBJ(sdb_object_vcreate(obj->name, obj->type, ap));
 135         va_end(ap);
 136         if (! new)
 137                 return NULL;
 138
 139         new->last_update = sobj->last_update;
 140         sdb_object_ref(SDB_OBJ(sobj->parent));
 141         new->parent = sobj->parent;
 142         return SDB_OBJ(new);
 143 } /* store_obj_clone */
 144
 145 static int
 146 sdb_store_obj_init(sdb_object_t *obj, va_list ap)
 147 {
 148         sdb_store_obj_t *sobj = SDB_STORE_OBJ(obj);
 149         int ret;
 150
 151         ret = store_obj_init(obj, ap);
 152         if (ret)
 153                 return ret;
 154
 155         sobj->type = va_arg(ap, int);
 156
 157         sobj->children = sdb_llist_create();
 158         if (! sobj->children)
 159                 return -1;
 160         sobj->attributes = sdb_llist_create();
 161         if (! sobj->attributes)
 162                 return -1;
 163         return 0;
 164 } /* sdb_store_obj_init */
 165
 166 static void
 167 sdb_store_obj_destroy(sdb_object_t *obj)
 168 {
 169         sdb_store_obj_t *sobj = SDB_STORE_OBJ(obj);
 170
 171         assert(obj);
 172
 173         store_obj_destroy(obj);
 174
 175         if (sobj->children)
 176                 sdb_llist_destroy(sobj->children);
 177         if (sobj->attributes)
 178                 sdb_llist_destroy(sobj->attributes);
 179 } /* sdb_store_obj_destroy */
 180
 181 static sdb_object_t *
 182 sdb_store_obj_clone(const sdb_object_t *obj)
 183 {
 184         const sdb_store_obj_t *sobj = SDB_CONST_STORE_OBJ(obj);
 185         sdb_store_obj_t *new;
 186
 187         new = SDB_STORE_OBJ(store_obj_clone(obj, sobj->_last_update, sobj->type));
 188         if (! new)
 189                 return NULL;
 190
 191         if (sobj->children) {
 192                 sdb_llist_destroy(new->children);
 193                 new->children = sdb_llist_clone(sobj->children);
 194                 if (! new->children) {
 195                         sdb_object_deref(SDB_OBJ(new));
 196                         return NULL;
 197                 }
 198         }
 199         if (sobj->attributes) {
 200                 sdb_llist_destroy(new->attributes);
 201                 new->attributes = sdb_llist_clone(sobj->attributes);
 202                 if (! new->attributes) {
 203                         sdb_object_deref(SDB_OBJ(new));
 204                         return NULL;
 205                 }
 206         }
 207
 208         return SDB_OBJ(new);
 209 } /* sdb_store_obj_clone */
 210
 211 static int
 212 sdb_attr_init(sdb_object_t *obj, va_list ap)
 213 {
 214         const char *value;
 215         int ret;
 216
 217         ret = store_obj_init(obj, ap);
 218         if (ret)
 219                 return ret;
 220         value = va_arg(ap, const char *);
 221
 222         SDB_ATTR(obj)->value = strdup(value);
 223         if (! SDB_ATTR(obj)->value)
 224                 return -1;
 225         return 0;
 226 } /* sdb_attr_init */
 227
 228 static void
 229 sdb_attr_destroy(sdb_object_t *obj)
 230 {
 231         assert(obj);
 232
 233         store_obj_destroy(obj);
 234
 235         if (SDB_ATTR(obj)->value)
 236                 free(SDB_ATTR(obj)->value);
 237 } /* sdb_attr_destroy */
 238
 239 static sdb_object_t *
 240 sdb_attr_clone(const sdb_object_t *obj)
 241 {
 242         const sdb_attribute_t *attr = (const sdb_attribute_t *)obj;
 243         sdb_attribute_t *new;
 244
 245         new = SDB_ATTR(store_obj_clone(obj, attr->_last_update, attr->value));
 246         if (! new)
 247                 return NULL;
 248         return SDB_OBJ(new);
 249 } /* sdb_attr_clone */
 250
 251 static sdb_type_t sdb_store_obj_type = {
 252         sizeof(sdb_store_obj_t),
 253
 254         sdb_store_obj_init,
 255         sdb_store_obj_destroy,
 256         sdb_store_obj_clone
 257 };
 258
 259 static sdb_type_t sdb_attribute_type = {
 260         sizeof(sdb_attribute_t),
 261
 262         sdb_attr_init,
 263         sdb_attr_destroy,
 264         sdb_attr_clone
 265 };
 266
 267 /*
 268  * private helper functions
 269  */
 270
 271 static sdb_store_obj_t *
 272 sdb_store_lookup_in_list(sdb_llist_t *l, int type, const char *name)
 273 {
 274         sdb_llist_iter_t *iter;
 275
 276         if (! l)
 277                 return NULL;
 278
 279         iter = sdb_llist_get_iter(l);
 280         if (! iter)
 281                 return NULL;
 282
 283         while (sdb_llist_iter_has_next(iter)) {
 284                 sdb_store_obj_t *sobj = SDB_STORE_OBJ(sdb_llist_iter_get_next(iter));
 285                 assert(sobj);
 286
 287                 if ((sobj->type == type)
 288                                 && (! strcasecmp(SDB_OBJ(sobj)->name, name))) {
 289                         sdb_llist_iter_destroy(iter);
 290                         return sobj;
 291                 }
 292
 293                 sobj = sdb_store_lookup_in_list(sobj->children, type, name);
 294                 if (sobj) {
 295                         sdb_llist_iter_destroy(iter);
 296                         return sobj;
 297                 }
 298         }
 299         sdb_llist_iter_destroy(iter);
 300         return NULL;
 301 } /* sdb_store_lookup_in_list */
 302
 303 static sdb_store_obj_t *
 304 sdb_store_lookup(int type, const char *name)
 305 {
 306         return sdb_store_lookup_in_list(obj_list, type, name);
 307 } /* sdb_store_lookup */
 308
 309 /* The obj_lock has to be acquired before calling this function. */
 310 static int
 311 store_obj(int parent_type, const char *parent_name,
 312                 int type, const char *name, sdb_time_t last_update,
 313                 store_obj_t **updated_obj)
 314 {
 315         sdb_llist_t *parent_list;
 316         store_obj_t *old;
 317         int status = 0;
 318
 319         if (! name)
 320                 return -1;
 321
 322         if (last_update <= 0)
 323                 last_update = sdb_gettime();
 324
 325         assert((parent_type == 0)
 326                         || (parent_type == SDB_HOST)
 327                         || (parent_type == SDB_SERVICE));
 328         assert((type == 0)
 329                         || (type == SDB_HOST)
 330                         || (type == SDB_SERVICE)
 331                         || (type == SDB_ATTRIBUTE));
 332
 333
 334         if (! obj_list) {
 335                 if (! (obj_list = sdb_llist_create()))
 336                         return -1;
 337         }
 338         parent_list = obj_list;
 339
 340         if (parent_type && parent_name) {
 341                 sdb_store_obj_t *parent;
 342
 343                 parent = sdb_store_lookup(parent_type, parent_name);
 344                 if (! parent) {
 345                         sdb_log(SDB_LOG_ERR, "store: Failed to store %s '%s' - "
 346                                         "parent %s '%s' not found", TYPE_TO_NAME(type), name,
 347                                         TYPE_TO_NAME(parent_type), parent_name);
 348                         return -1;
 349                 }
 350
 351                 if (type == SDB_ATTRIBUTE)
 352                         parent_list = parent->attributes;
 353                 else
 354                         parent_list = parent->children;
 355         }
 356
 357         /* TODO: only look into direct children? */
 358         if (type == SDB_ATTRIBUTE)
 359                 old = STORE_OBJ(sdb_llist_search_by_name(parent_list, name));
 360         else
 361                 old = STORE_OBJ(sdb_store_lookup_in_list(parent_list, type, name));
 362
 363         if (old) {
 364                 if (old->last_update > last_update) {
 365                         sdb_log(SDB_LOG_DEBUG, "store: Cannot update %s '%s' - "
 366                                         "value too old (%"PRIscTIME" < %"PRIscTIME")",
 367                                         TYPE_TO_NAME(type), name, last_update, old->last_update);
 368                         /* don't report an error; the object may be updated by multiple
 369                          * backends */
 370                         status = 1;
 371                 }
 372                 else {
 373                         old->last_update = last_update;
 374                 }
 375
 376                 if (updated_obj)
 377                         *updated_obj = old;
 378         }
 379         else {
 380                 store_obj_t *new;
 381
 382                 if (type == SDB_ATTRIBUTE)
 383                         /* the value will be updated by the caller */
 384                         new = STORE_OBJ(sdb_object_create(name, sdb_attribute_type,
 385                                                 last_update, NULL));
 386                 else
 387                         new = STORE_OBJ(sdb_object_create(name, sdb_store_obj_type,
 388                                                 last_update, type));
 389
 390                 if (! new) {
 391                         char errbuf[1024];
 392                         sdb_log(SDB_LOG_ERR, "store: Failed to create %s '%s': %s",
 393                                         TYPE_TO_NAME(type), name,
 394                                         sdb_strerror(errno, errbuf, sizeof(errbuf)));
 395                         return -1;
 396                 }
 397
 398                 /* TODO: insert type-aware; the current version works as long as we
 399                  * don't support to store hierarchical data */
 400                 status = sdb_llist_insert_sorted(parent_list, SDB_OBJ(new),
 401                                 sdb_object_cmp_by_name);
 402
 403                 /* pass control to the list or destroy in case of an error */
 404                 sdb_object_deref(SDB_OBJ(new));
 405
 406                 if (updated_obj)
 407                         *updated_obj = new;
 408         }
 409         return status;
 410 } /* sdb_store_obj */
 411
 412 /*
 413  * public API
 414  */
 415
 416 int
 417 sdb_store_host(const char *name, sdb_time_t last_update)
 418 {
 419         char *cname;
 420         int status;
 421
 422         if (! name)
 423                 return -1;
 424
 425         cname = sdb_plugin_cname(strdup(name));
 426         if (! cname) {
 427                 sdb_log(SDB_LOG_ERR, "store: strdup failed");
 428                 return -1;
 429         }
 430
 431         pthread_rwlock_wrlock(&obj_lock);
 432         status = store_obj(/* parent = */ 0, NULL,
 433                         /* stored object = */ SDB_HOST, cname, last_update,
 434                         /* updated_obj = */ NULL);
 435         pthread_rwlock_unlock(&obj_lock);
 436         free(cname);
 437         return status;
 438 } /* sdb_store_host */
 439
 440 _Bool
 441 sdb_store_has_host(const char *name)
 442 {
 443         sdb_store_obj_t *host;
 444
 445         if (! name)
 446                 return NULL;
 447
 448         host = sdb_store_lookup(SDB_HOST, name);
 449         return host != NULL;
 450 } /* sdb_store_has_host */
 451
 452 int
 453 sdb_store_attribute(const char *hostname, const char *key, const char *value,
 454                 sdb_time_t last_update)
 455 {
 456         char *cname;
 457         int status;
 458
 459         store_obj_t *updated_attr = NULL;
 460
 461         if ((! hostname) || (! key))
 462                 return -1;
 463
 464         cname = sdb_plugin_cname(strdup(hostname));
 465         if (! cname) {
 466                 sdb_log(SDB_LOG_ERR, "store: strdup failed");
 467                 return -1;
 468         }
 469
 470         pthread_rwlock_wrlock(&obj_lock);
 471         status = store_obj(/* parent = */ SDB_HOST, cname,
 472                         /* stored object = */ SDB_ATTRIBUTE, key, last_update,
 473                         &updated_attr);
 474
 475         SDB_ATTR(updated_attr)->value = strdup(value);
 476         if (! SDB_ATTR(updated_attr)->value) {
 477                 sdb_object_deref(SDB_OBJ(updated_attr));
 478                 status = -1;
 479         }
 480         pthread_rwlock_unlock(&obj_lock);
 481         free(cname);
 482         return status;
 483 } /* sdb_store_attribute */
 484
 485 int
 486 sdb_store_service(const char *hostname, const char *name,
 487                 sdb_time_t last_update)
 488 {
 489         char *cname;
 490         int status;
 491
 492         if ((! hostname) || (! name))
 493                 return -1;
 494
 495         cname = sdb_plugin_cname(strdup(hostname));
 496         if (! cname) {
 497                 sdb_log(SDB_LOG_ERR, "store: strdup failed");
 498                 return -1;
 499         }
 500
 501         pthread_rwlock_wrlock(&obj_lock);
 502         status = store_obj(/* parent = */ SDB_HOST, cname,
 503                         /* stored object = */ SDB_SERVICE, name, last_update,
 504                         /* updated obj = */ NULL);
 505         pthread_rwlock_unlock(&obj_lock);
 506         free(cname);
 507         return status;
 508 } /* sdb_store_service */
 509
 510 /* TODO: actually support hierarchical data */
 511 int
 512 sdb_store_dump(FILE *fh)
 513 {
 514         sdb_llist_iter_t *host_iter;
 515
 516         if (! fh)
 517                 return -1;
 518
 519         pthread_rwlock_rdlock(&obj_lock);
 520
 521         host_iter = sdb_llist_get_iter(obj_list);
 522         if (! host_iter) {
 523                 pthread_rwlock_unlock(&obj_lock);
 524                 return -1;
 525         }
 526
 527         while (sdb_llist_iter_has_next(host_iter)) {
 528                 sdb_store_obj_t *host = SDB_STORE_OBJ(sdb_llist_iter_get_next(host_iter));
 529                 sdb_llist_iter_t *svc_iter;
 530                 sdb_llist_iter_t *attr_iter;
 531
 532                 char time_str[64];
 533
 534                 assert(host);
 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                 fprintf(fh, "Host '%s' (last updated: %s):\n",
 542                                 SDB_OBJ(host)->name, time_str);
 543
 544                 attr_iter = sdb_llist_get_iter(host->attributes);
 545                 if (! attr_iter) {
 546                         char errbuf[1024];
 547                         fprintf(fh, "Failed to retrieve attributes: %s\n",
 548                                         sdb_strerror(errno, errbuf, sizeof(errbuf)));
 549                         continue;
 550                 }
 551
 552                 while (sdb_llist_iter_has_next(attr_iter)) {
 553                         sdb_attribute_t *attr = SDB_ATTR(sdb_llist_iter_get_next(attr_iter));
 554                         assert(attr);
 555
 556                         if (! sdb_strftime(time_str, sizeof(time_str),
 557                                                 "%F %T %z", attr->_last_update))
 558                                 snprintf(time_str, sizeof(time_str), "<error>");
 559                         time_str[sizeof(time_str) - 1] = '\0';
 560
 561                         fprintf(fh, "\tAttribute '%s' -> '%s' (last updated: %s)\n",
 562                                         SDB_OBJ(attr)->name, attr->value, time_str);
 563                 }
 564
 565                 sdb_llist_iter_destroy(attr_iter);
 566
 567                 svc_iter = sdb_llist_get_iter(host->children);
 568                 if (! svc_iter) {
 569                         char errbuf[1024];
 570                         fprintf(fh, "Failed to retrieve services: %s\n",
 571                                         sdb_strerror(errno, errbuf, sizeof(errbuf)));
 572                         continue;
 573                 }
 574
 575                 while (sdb_llist_iter_has_next(svc_iter)) {
 576                         sdb_store_obj_t *svc = SDB_STORE_OBJ(sdb_llist_iter_get_next(svc_iter));
 577                         assert(svc);
 578
 579                         if (! sdb_strftime(time_str, sizeof(time_str),
 580                                                 "%F %T %z", svc->_last_update))
 581                                 snprintf(time_str, sizeof(time_str), "<error>");
 582                         time_str[sizeof(time_str) - 1] = '\0';
 583
 584                         fprintf(fh, "\tService '%s' (last updated: %s)\n",
 585                                         SDB_OBJ(svc)->name, time_str);
 586                 }
 587
 588                 sdb_llist_iter_destroy(svc_iter);
 589         }
 590
 591         sdb_llist_iter_destroy(host_iter);
 592         pthread_rwlock_unlock(&obj_lock);
 593         return 0;
 594 } /* sdb_store_dump */
 595
 596 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 597