Merge remote-tracking branch 'remotes/rth/tags/pull-tcg-20210921' into staging
[qemu.git] / qobject / qdict.c
1 /*
2 * QDict Module
3 *
4 * Copyright (C) 2009 Red Hat Inc.
5 *
6 * Authors:
7 * Luiz Capitulino <lcapitulino@redhat.com>
8 *
9 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
10 * See the COPYING.LIB file in the top-level directory.
11 */
12
13 #include "qemu/osdep.h"
14 #include "qapi/qmp/qnum.h"
15 #include "qapi/qmp/qdict.h"
16 #include "qapi/qmp/qbool.h"
17 #include "qapi/qmp/qnull.h"
18 #include "qapi/qmp/qstring.h"
19 #include "qobject-internal.h"
20
21 /**
22 * qdict_new(): Create a new QDict
23 *
24 * Return strong reference.
25 */
26 QDict *qdict_new(void)
27 {
28 QDict *qdict;
29
30 qdict = g_malloc0(sizeof(*qdict));
31 qobject_init(QOBJECT(qdict), QTYPE_QDICT);
32
33 return qdict;
34 }
35
36 /**
37 * tdb_hash(): based on the hash algorithm from gdbm, via tdb
38 * (from module-init-tools)
39 */
40 static unsigned int tdb_hash(const char *name)
41 {
42 unsigned value; /* Used to compute the hash value. */
43 unsigned i; /* Used to cycle through random values. */
44
45 /* Set the initial value from the key size. */
46 for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++) {
47 value = (value + (((const unsigned char *)name)[i] << (i * 5 % 24)));
48 }
49
50 return (1103515243 * value + 12345);
51 }
52
53 /**
54 * alloc_entry(): allocate a new QDictEntry
55 */
56 static QDictEntry *alloc_entry(const char *key, QObject *value)
57 {
58 QDictEntry *entry;
59
60 entry = g_malloc0(sizeof(*entry));
61 entry->key = g_strdup(key);
62 entry->value = value;
63
64 return entry;
65 }
66
67 /**
68 * qdict_entry_value(): Return qdict entry value
69 *
70 * Return weak reference.
71 */
72 QObject *qdict_entry_value(const QDictEntry *entry)
73 {
74 return entry->value;
75 }
76
77 /**
78 * qdict_entry_key(): Return qdict entry key
79 *
80 * Return a *pointer* to the string, it has to be duplicated before being
81 * stored.
82 */
83 const char *qdict_entry_key(const QDictEntry *entry)
84 {
85 return entry->key;
86 }
87
88 /**
89 * qdict_find(): List lookup function
90 */
91 static QDictEntry *qdict_find(const QDict *qdict,
92 const char *key, unsigned int bucket)
93 {
94 QDictEntry *entry;
95
96 QLIST_FOREACH(entry, &qdict->table[bucket], next)
97 if (!strcmp(entry->key, key)) {
98 return entry;
99 }
100
101 return NULL;
102 }
103
104 /**
105 * qdict_put_obj(): Put a new QObject into the dictionary
106 *
107 * Insert the pair 'key:value' into 'qdict', if 'key' already exists
108 * its 'value' will be replaced.
109 *
110 * This is done by freeing the reference to the stored QObject and
111 * storing the new one in the same entry.
112 *
113 * NOTE: ownership of 'value' is transferred to the QDict
114 */
115 void qdict_put_obj(QDict *qdict, const char *key, QObject *value)
116 {
117 unsigned int bucket;
118 QDictEntry *entry;
119
120 bucket = tdb_hash(key) % QDICT_BUCKET_MAX;
121 entry = qdict_find(qdict, key, bucket);
122 if (entry) {
123 /* replace key's value */
124 qobject_unref(entry->value);
125 entry->value = value;
126 } else {
127 /* allocate a new entry */
128 entry = alloc_entry(key, value);
129 QLIST_INSERT_HEAD(&qdict->table[bucket], entry, next);
130 qdict->size++;
131 }
132 }
133
134 void qdict_put_int(QDict *qdict, const char *key, int64_t value)
135 {
136 qdict_put(qdict, key, qnum_from_int(value));
137 }
138
139 void qdict_put_bool(QDict *qdict, const char *key, bool value)
140 {
141 qdict_put(qdict, key, qbool_from_bool(value));
142 }
143
144 void qdict_put_str(QDict *qdict, const char *key, const char *value)
145 {
146 qdict_put(qdict, key, qstring_from_str(value));
147 }
148
149 void qdict_put_null(QDict *qdict, const char *key)
150 {
151 qdict_put(qdict, key, qnull());
152 }
153
154 /**
155 * qdict_get(): Lookup for a given 'key'
156 *
157 * Return a weak reference to the QObject associated with 'key' if
158 * 'key' is present in the dictionary, NULL otherwise.
159 */
160 QObject *qdict_get(const QDict *qdict, const char *key)
161 {
162 QDictEntry *entry;
163
164 entry = qdict_find(qdict, key, tdb_hash(key) % QDICT_BUCKET_MAX);
165 return (entry == NULL ? NULL : entry->value);
166 }
167
168 /**
169 * qdict_haskey(): Check if 'key' exists
170 *
171 * Return 1 if 'key' exists in the dict, 0 otherwise
172 */
173 int qdict_haskey(const QDict *qdict, const char *key)
174 {
175 unsigned int bucket = tdb_hash(key) % QDICT_BUCKET_MAX;
176 return (qdict_find(qdict, key, bucket) == NULL ? 0 : 1);
177 }
178
179 /**
180 * qdict_size(): Return the size of the dictionary
181 */
182 size_t qdict_size(const QDict *qdict)
183 {
184 return qdict->size;
185 }
186
187 /**
188 * qdict_get_double(): Get an number mapped by 'key'
189 *
190 * This function assumes that 'key' exists and it stores a QNum.
191 *
192 * Return number mapped by 'key'.
193 */
194 double qdict_get_double(const QDict *qdict, const char *key)
195 {
196 return qnum_get_double(qobject_to(QNum, qdict_get(qdict, key)));
197 }
198
199 /**
200 * qdict_get_int(): Get an integer mapped by 'key'
201 *
202 * This function assumes that 'key' exists and it stores a
203 * QNum representable as int.
204 *
205 * Return integer mapped by 'key'.
206 */
207 int64_t qdict_get_int(const QDict *qdict, const char *key)
208 {
209 return qnum_get_int(qobject_to(QNum, qdict_get(qdict, key)));
210 }
211
212 /**
213 * qdict_get_bool(): Get a bool mapped by 'key'
214 *
215 * This function assumes that 'key' exists and it stores a
216 * QBool object.
217 *
218 * Return bool mapped by 'key'.
219 */
220 bool qdict_get_bool(const QDict *qdict, const char *key)
221 {
222 return qbool_get_bool(qobject_to(QBool, qdict_get(qdict, key)));
223 }
224
225 /**
226 * qdict_get_qlist(): If @qdict maps @key to a QList, return it, else NULL.
227 */
228 QList *qdict_get_qlist(const QDict *qdict, const char *key)
229 {
230 return qobject_to(QList, qdict_get(qdict, key));
231 }
232
233 /**
234 * qdict_get_qdict(): If @qdict maps @key to a QDict, return it, else NULL.
235 */
236 QDict *qdict_get_qdict(const QDict *qdict, const char *key)
237 {
238 return qobject_to(QDict, qdict_get(qdict, key));
239 }
240
241 /**
242 * qdict_get_str(): Get a pointer to the stored string mapped
243 * by 'key'
244 *
245 * This function assumes that 'key' exists and it stores a
246 * QString object.
247 *
248 * Return pointer to the string mapped by 'key'.
249 */
250 const char *qdict_get_str(const QDict *qdict, const char *key)
251 {
252 return qstring_get_str(qobject_to(QString, qdict_get(qdict, key)));
253 }
254
255 /**
256 * qdict_get_try_int(): Try to get integer mapped by 'key'
257 *
258 * Return integer mapped by 'key', if it is not present in the
259 * dictionary or if the stored object is not a QNum representing an
260 * integer, 'def_value' will be returned.
261 */
262 int64_t qdict_get_try_int(const QDict *qdict, const char *key,
263 int64_t def_value)
264 {
265 QNum *qnum = qobject_to(QNum, qdict_get(qdict, key));
266 int64_t val;
267
268 if (!qnum || !qnum_get_try_int(qnum, &val)) {
269 return def_value;
270 }
271
272 return val;
273 }
274
275 /**
276 * qdict_get_try_bool(): Try to get a bool mapped by 'key'
277 *
278 * Return bool mapped by 'key', if it is not present in the
279 * dictionary or if the stored object is not of QBool type
280 * 'def_value' will be returned.
281 */
282 bool qdict_get_try_bool(const QDict *qdict, const char *key, bool def_value)
283 {
284 QBool *qbool = qobject_to(QBool, qdict_get(qdict, key));
285
286 return qbool ? qbool_get_bool(qbool) : def_value;
287 }
288
289 /**
290 * qdict_get_try_str(): Try to get a pointer to the stored string
291 * mapped by 'key'
292 *
293 * Return a pointer to the string mapped by 'key', if it is not present
294 * in the dictionary or if the stored object is not of QString type
295 * NULL will be returned.
296 */
297 const char *qdict_get_try_str(const QDict *qdict, const char *key)
298 {
299 QString *qstr = qobject_to(QString, qdict_get(qdict, key));
300
301 return qstr ? qstring_get_str(qstr) : NULL;
302 }
303
304 static QDictEntry *qdict_next_entry(const QDict *qdict, int first_bucket)
305 {
306 int i;
307
308 for (i = first_bucket; i < QDICT_BUCKET_MAX; i++) {
309 if (!QLIST_EMPTY(&qdict->table[i])) {
310 return QLIST_FIRST(&qdict->table[i]);
311 }
312 }
313
314 return NULL;
315 }
316
317 /**
318 * qdict_first(): Return first qdict entry for iteration.
319 */
320 const QDictEntry *qdict_first(const QDict *qdict)
321 {
322 return qdict_next_entry(qdict, 0);
323 }
324
325 /**
326 * qdict_next(): Return next qdict entry in an iteration.
327 */
328 const QDictEntry *qdict_next(const QDict *qdict, const QDictEntry *entry)
329 {
330 QDictEntry *ret;
331
332 ret = QLIST_NEXT(entry, next);
333 if (!ret) {
334 unsigned int bucket = tdb_hash(entry->key) % QDICT_BUCKET_MAX;
335 ret = qdict_next_entry(qdict, bucket + 1);
336 }
337
338 return ret;
339 }
340
341 /**
342 * qdict_clone_shallow(): Clones a given QDict. Its entries are not copied, but
343 * another reference is added.
344 */
345 QDict *qdict_clone_shallow(const QDict *src)
346 {
347 QDict *dest;
348 QDictEntry *entry;
349 int i;
350
351 dest = qdict_new();
352
353 for (i = 0; i < QDICT_BUCKET_MAX; i++) {
354 QLIST_FOREACH(entry, &src->table[i], next) {
355 qdict_put_obj(dest, entry->key, qobject_ref(entry->value));
356 }
357 }
358
359 return dest;
360 }
361
362 /**
363 * qentry_destroy(): Free all the memory allocated by a QDictEntry
364 */
365 static void qentry_destroy(QDictEntry *e)
366 {
367 assert(e != NULL);
368 assert(e->key != NULL);
369 assert(e->value != NULL);
370
371 qobject_unref(e->value);
372 g_free(e->key);
373 g_free(e);
374 }
375
376 /**
377 * qdict_del(): Delete a 'key:value' pair from the dictionary
378 *
379 * This will destroy all data allocated by this entry.
380 */
381 void qdict_del(QDict *qdict, const char *key)
382 {
383 QDictEntry *entry;
384
385 entry = qdict_find(qdict, key, tdb_hash(key) % QDICT_BUCKET_MAX);
386 if (entry) {
387 QLIST_REMOVE(entry, next);
388 qentry_destroy(entry);
389 qdict->size--;
390 }
391 }
392
393 /**
394 * qdict_is_equal(): Test whether the two QDicts are equal
395 *
396 * Here, equality means whether they contain the same keys and whether
397 * the respective values are in turn equal (i.e. invoking
398 * qobject_is_equal() on them yields true).
399 */
400 bool qdict_is_equal(const QObject *x, const QObject *y)
401 {
402 const QDict *dict_x = qobject_to(QDict, x);
403 const QDict *dict_y = qobject_to(QDict, y);
404 const QDictEntry *e;
405
406 if (qdict_size(dict_x) != qdict_size(dict_y)) {
407 return false;
408 }
409
410 for (e = qdict_first(dict_x); e; e = qdict_next(dict_x, e)) {
411 const QObject *obj_x = qdict_entry_value(e);
412 const QObject *obj_y = qdict_get(dict_y, qdict_entry_key(e));
413
414 if (!qobject_is_equal(obj_x, obj_y)) {
415 return false;
416 }
417 }
418
419 return true;
420 }
421
422 /**
423 * qdict_destroy_obj(): Free all the memory allocated by a QDict
424 */
425 void qdict_destroy_obj(QObject *obj)
426 {
427 int i;
428 QDict *qdict;
429
430 assert(obj != NULL);
431 qdict = qobject_to(QDict, obj);
432
433 for (i = 0; i < QDICT_BUCKET_MAX; i++) {
434 QDictEntry *entry = QLIST_FIRST(&qdict->table[i]);
435 while (entry) {
436 QDictEntry *tmp = QLIST_NEXT(entry, next);
437 QLIST_REMOVE(entry, next);
438 qentry_destroy(entry);
439 entry = tmp;
440 }
441 }
442
443 g_free(qdict);
444 }