578fb51e7087e72b634cb60f4b44cc32738a5b9d
1 /*
2 * SysDB - src/include/core/store.h
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 */
28 #ifndef SDB_CORE_STORE_H
29 #define SDB_CORE_STORE_H 1
31 #include "sysdb.h"
32 #include "core/object.h"
33 #include "core/data.h"
34 #include "core/time.h"
35 #include "utils/strbuf.h"
37 #include <stdio.h>
39 #ifdef __cplusplus
40 extern "C" {
41 #endif
43 /*
44 * Store object types.
45 */
46 enum {
47 SDB_HOST = 1,
48 SDB_SERVICE,
49 SDB_ATTRIBUTE,
50 };
51 #define SDB_STORE_TYPE_TO_NAME(t) \
52 (((t) == SDB_HOST) ? "host" \
53 : ((t) == SDB_SERVICE) ? "service" \
54 : ((t) == SDB_ATTRIBUTE) ? "attribute" : "unknown")
57 /*
58 * sdb_store_obj_t represents the super-class of any object stored in the
59 * database. It inherits from sdb_object_t and may safely be cast to a generic
60 * object to access its name.
61 */
62 struct sdb_store_obj;
63 typedef struct sdb_store_obj sdb_store_obj_t;
65 /*
66 * sdb_store_clear:
67 * Clear the entire store and remove all stored objects.
68 */
69 void
70 sdb_store_clear(void);
72 /*
73 * sdb_store_host:
74 * Add/update a host in the store. If the host, identified by its
75 * canonicalized name, already exists, it will be updated according to the
76 * specified name and timestamp. Else, a new entry will be created in the
77 * store. Any memory required for storing the entry will be allocated an
78 * managed by the store itself.
79 *
80 * Returns:
81 * - 0 on success
82 * - a positive value if the new entry is older than the currently stored
83 * entry (in this case, no update will happen)
84 * - a negative value on error
85 */
86 int
87 sdb_store_host(const char *name, sdb_time_t last_update);
89 /*
90 * sdb_store_has_host:
91 * sdb_store_get_host:
92 * Query the store for a host by its (canonicalized) name.
93 *
94 * sdb_store_get_host increments the ref count of the host object. The caller
95 * needs to deref it when no longer using it.
96 */
97 _Bool
98 sdb_store_has_host(const char *name);
100 sdb_store_obj_t *
101 sdb_store_get_host(const char *name);
103 /*
104 * sdb_store_attribute:
105 * Add/update a host's attribute in the store. If the attribute, identified by
106 * its key, already exists for the specified host, it will be updated to the
107 * specified values. If the referenced host does not exist, an error will be
108 * reported. Else, a new entry will be created in the store. Any memory
109 * required for storing the entry will be allocated and managed by the store
110 * itself.
111 *
112 * Returns:
113 * - 0 on success
114 * - a positive value if the new entry is older than the currently stored
115 * entry (in this case, no update will happen)
116 * - a negative value on error
117 */
118 int
119 sdb_store_attribute(const char *hostname,
120 const char *key, const sdb_data_t *value,
121 sdb_time_t last_update);
123 /*
124 * sdb_store_service:
125 * Add/update a service in the store. If the service, identified by its name,
126 * already exists for the specified host, it will be updated according to the
127 * specified 'service' object. If the referenced host does not exist, an error
128 * will be reported. Else, a new entry will be created in the store. Any
129 * memory required for storing the entry will be allocated an managed by the
130 * store itself. The specified service-object will not be referenced or
131 * further accessed.
132 *
133 * Returns:
134 * - 0 on success
135 * - a positive value if the new entry is older than the currently stored
136 * entry (in this case, no update will happen)
137 * - a negative value on error
138 */
139 int
140 sdb_store_service(const char *hostname, const char *name,
141 sdb_time_t last_update);
143 /*
144 * sdb_store_service_attr:
145 * Add/update a service's attribute in the store. If the attribute, identified
146 * by its key, already exists for the specified service, it will be updated to
147 * the specified value. If the references service (for the specified host)
148 * does not exist, an error will be reported. Any memory required for storing
149 * the entry will be allocated and managed by the store itself.
150 *
151 * Returns:
152 * - 0 on success
153 * - a positive value if the new entry is older than the currently stored
154 * entry (in this case, no update will happen)
155 * - a negative value on error
156 */
157 int
158 sdb_store_service_attr(const char *hostname, const char *service,
159 const char *key, const sdb_data_t *value, sdb_time_t last_update);
161 /*
162 * Expressions specify arithmetic expressions.
163 *
164 * A expression object inherits from sdb_object_t and, thus, may safely be
165 * cast to a generic object.
166 */
167 struct sdb_store_expr;
168 typedef struct sdb_store_expr sdb_store_expr_t;
169 #define SDB_STORE_EXPR(obj) ((sdb_store_expr_t *)(obj))
171 /*
172 * sdb_store_expr_create:
173 * Creates an arithmetic expression implementing the specified operator on the
174 * specified left and right operand.
175 *
176 * Returns:
177 * - an expression object on success
178 * - NULL else
179 */
180 sdb_store_expr_t *
181 sdb_store_expr_create(int op, sdb_store_expr_t *left, sdb_store_expr_t *right);
183 /*
184 * sdb_store_expr_constvalue:
185 * Creates an expression which evaluates to the specified constant value.
186 *
187 * Returns:
188 * - an expression object on success
189 * - NULL else
190 */
191 sdb_store_expr_t *
192 sdb_store_expr_constvalue(const sdb_data_t *value);
194 /*
195 * sdb_store_expr_eval:
196 * Evaluate an expression and stores the result in 'res'. The result's value
197 * will be allocated dynamically if necessary and, thus, should be free'd by
198 * the caller (e.g. using sdb_data_free_datum);
199 *
200 * Returns:
201 * - 0 on success
202 * - a negative value else
203 */
204 int
205 sdb_store_expr_eval(sdb_store_expr_t *expr, sdb_data_t *res);
207 /*
208 * Conditionals may be used to lookup hosts from the store based on a
209 * conditional expression.
210 *
211 * A conditional object inherits from sdb_object_t and, thus, may safely be
212 * cast to a generic object.
213 */
214 struct sdb_store_cond;
215 typedef struct sdb_store_cond sdb_store_cond_t;
216 #define SDB_STORE_COND(obj) ((sdb_store_cond_t *)(obj))
218 /*
219 * sdb_store_attr_cond:
220 * Creates a conditional based on attribute values. The value of stored
221 * attributes is compared against the value the expression evaluates to. See
222 * sdb_data_cmp for details about the comparison.
223 */
224 sdb_store_cond_t *
225 sdb_store_attr_cond(const char *name, sdb_store_expr_t *expr);
227 /*
228 * Store matchers may be used to lookup hosts from the store based on their
229 * various attributes. Service and attribute matchers are applied to a host's
230 * services and attributes and evaluate to true if *any* service or attribute
231 * matches.
232 *
233 * A store matcher object inherits from sdb_object_t and, thus, may safely be
234 * cast to a generic object.
235 */
236 struct sdb_store_matcher;
237 typedef struct sdb_store_matcher sdb_store_matcher_t;
238 #define SDB_STORE_MATCHER(obj) ((sdb_store_matcher_t *)(obj))
240 /*
241 * sdb_store_name_matcher:
242 * Creates a matcher matching by the specified object type's name. If 're' is
243 * true, the specified name is treated as a POSIX extended regular expression.
244 * Else, the exact name has to match (case-insensitive).
245 */
246 sdb_store_matcher_t *
247 sdb_store_name_matcher(int type, const char *name, _Bool re);
249 /*
250 * sdb_store_attr_matcher:
251 * Creates a matcher matching attributes based on their value. If 're' is
252 * true, the specified name is treated as a POSIX extended regular expression.
253 * Else, the exact name has to match (case-insensitive).
254 */
255 sdb_store_matcher_t *
256 sdb_store_attr_matcher(const char *name, const char *value, _Bool re);
258 /*
259 * sdb_store_isnull_matcher:
260 * Creates a matcher matching "missing" attributes.
261 */
262 sdb_store_matcher_t *
263 sdb_store_isnull_matcher(const char *attr_name);
265 /*
266 * sdb_store_lt_matcher, sdb_store_le_matcher, sdb_store_eq_matcher,
267 * sdb_store_ge_matcher, sdb_store_gt_matcher:
268 * Creates a matcher based on a conditional. The matcher matches objects for
269 * which the conditional evaluates the object to compare less than, less or
270 * equal, equal, greater or equal, or greater than the conditional's value
271 * repsectively.
272 */
273 sdb_store_matcher_t *
274 sdb_store_lt_matcher(sdb_store_cond_t *cond);
275 sdb_store_matcher_t *
276 sdb_store_le_matcher(sdb_store_cond_t *cond);
277 sdb_store_matcher_t *
278 sdb_store_eq_matcher(sdb_store_cond_t *cond);
279 sdb_store_matcher_t *
280 sdb_store_ge_matcher(sdb_store_cond_t *cond);
281 sdb_store_matcher_t *
282 sdb_store_gt_matcher(sdb_store_cond_t *cond);
284 /*
285 * sdb_store_matcher_parse_cmp:
286 * Parse a simple compare expression (<obj_type>.<attr> <op> <expression>).
287 *
288 * Returns:
289 * - a matcher object on success
290 * - NULL else
291 */
292 sdb_store_matcher_t *
293 sdb_store_matcher_parse_cmp(const char *obj_type, const char *attr,
294 const char *op, sdb_store_expr_t *expr);
296 /*
297 * sdb_store_dis_matcher:
298 * Creates a matcher matching the disjunction (logical OR) of two matchers.
299 */
300 sdb_store_matcher_t *
301 sdb_store_dis_matcher(sdb_store_matcher_t *left, sdb_store_matcher_t *right);
303 /*
304 * sdb_store_con_matcher:
305 * Creates a matcher matching the conjunction (logical AND) of two matchers.
306 */
307 sdb_store_matcher_t *
308 sdb_store_con_matcher(sdb_store_matcher_t *left, sdb_store_matcher_t *right);
310 /*
311 * sdb_store_con_matcher::
312 * Creates a matcher matching the inverse (logical NOT) of a matcher.
313 */
314 sdb_store_matcher_t *
315 sdb_store_inv_matcher(sdb_store_matcher_t *m);
317 /*
318 * sdb_store_matcher_matches:
319 * Check whether the specified matcher matches the specified store object. If
320 * specified, the filter will be used to preselect objects for further
321 * evaluation. It is applied to any object that's used during the evaluation
322 * of the matcher. Only those objects matching the filter will be considered.
323 *
324 * Note that the filter is applied to all object types (hosts, service,
325 * attribute). Thus, any object-specific matchers are mostly unsuited for this
326 * purpose and, if used, may result in unexpected behavior.
327 *
328 * Returns:
329 * - 1 if the object matches
330 * - 0 else
331 */
332 int
333 sdb_store_matcher_matches(sdb_store_matcher_t *m, sdb_store_obj_t *obj,
334 sdb_store_matcher_t *filter);
336 /*
337 * sdb_store_matcher_tostring:
338 * Format a matcher object as string. This is meant for logging or debugging
339 * purposes.
340 */
341 char *
342 sdb_store_matcher_tostring(sdb_store_matcher_t *m, char *buf, size_t buflen);
344 /*
345 * sdb_store_lookup_cb:
346 * Lookup callback. It is called for each matching object when looking up data
347 * in the store. The lookup aborts if the callback returns non-zero.
348 */
349 typedef int (*sdb_store_lookup_cb)(sdb_store_obj_t *obj, void *user_data);
351 /*
352 * sdb_store_scan:
353 * Look up objects in the store. The specified callback function is called for
354 * each object in the store matching 'm'. The function performs a full scan of
355 * all hosts stored in the database. If specified, the filter will be used to
356 * preselect objects for further evaluation. See the description of
357 * 'sdb_store_matcher_matches' for details.
358 *
359 * Returns:
360 * - 0 on success
361 * - a negative value else
362 */
363 int
364 sdb_store_scan(sdb_store_matcher_t *m, sdb_store_matcher_t *filter,
365 sdb_store_lookup_cb cb, void *user_data);
367 /*
368 * Flags for serialization functions.
369 *
370 * By default, the full object will be included in the serialized output. When
371 * specifying any of the flags, the respective information will be left out.
372 */
373 enum {
374 SDB_SKIP_ATTRIBUTES = 1 << 0,
375 SDB_SKIP_SERVICES = 1 << 1,
376 SDB_SKIP_SERVICE_ATTRIBUTES = 1 << 2,
378 SDB_SKIP_ALL = 0xffff,
379 };
381 /*
382 * sdb_store_tojson:
383 * Serialize the entire store to JSON and append the result to the specified
384 * buffer.
385 *
386 * Returns:
387 * - 0 on success
388 * - a negative value on error
389 */
390 int
391 sdb_store_tojson(sdb_strbuf_t *buf, int flags);
393 /*
394 * sdb_store_host_tojson:
395 * Serialize a host object to JSON and append the result to the specified
396 * buffer.
397 *
398 * Returns:
399 * - 0 on success
400 * - a negative value on error
401 */
402 int
403 sdb_store_host_tojson(sdb_store_obj_t *host, sdb_strbuf_t *buf, int flags);
405 /*
406 * sdb_store_iter_cb:
407 * Store iterator callback. Iteration stops if the callback returns non-zero.
408 */
409 typedef int (*sdb_store_iter_cb)(sdb_store_obj_t *obj, void *user_data);
411 /*
412 * sdb_store_iterate:
413 * Iterate the entire store, calling the specified callback for each object.
414 * The user_data pointer is passed on to each call of the callback.
415 *
416 * Returns:
417 * - 0 on success
418 * - a negative value else
419 */
420 int
421 sdb_store_iterate(sdb_store_iter_cb cb, void *user_data);
423 #ifdef __cplusplus
424 } /* extern "C" */
425 #endif
427 #endif /* ! SDB_CORE_STORE_H */
429 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */