Merge remote-tracking branch 'remotes/cohuck-gitlab/tags/s390x-20210121' 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 return (1103515243 * value + 12345);
50 }
51
52 /**
53 * alloc_entry(): allocate a new QDictEntry
54 */
55 static QDictEntry *alloc_entry(const char *key, QObject *value)
56 {
57 QDictEntry *entry;
58
59 entry = g_malloc0(sizeof(*entry));
60 entry->key = g_strdup(key);
61 entry->value = value;
62
63 return entry;
64 }
65
66 /**
67 * qdict_entry_value(): Return qdict entry value
68 *
69 * Return weak reference.
70 */
71 QObject *qdict_entry_value(const QDictEntry *entry)
72 {
73 return entry->value;
74 }
75
76 /**
77 * qdict_entry_key(): Return qdict entry key
78 *
79 * Return a *pointer* to the string, it has to be duplicated before being
80 * stored.
81 */
82 const char *qdict_entry_key(const QDictEntry *entry)
83 {
84 return entry->key;
85 }
86
87 /**
88 * qdict_find(): List lookup function
89 */
90 static QDictEntry *qdict_find(const QDict *qdict,
91 const char *key, unsigned int bucket)
92 {
93 QDictEntry *entry;
94
95 QLIST_FOREACH(entry, &qdict->table[bucket], next)
96 if (!strcmp(entry->key, key))
97 return entry;
98
99 return NULL;
100 }
101
102 /**
103 * qdict_put_obj(): Put a new QObject into the dictionary
104 *
105 * Insert the pair 'key:value' into 'qdict', if 'key' already exists
106 * its 'value' will be replaced.
107 *
108 * This is done by freeing the reference to the stored QObject and
109 * storing the new one in the same entry.
110 *
111 * NOTE: ownership of 'value' is transferred to the QDict
112 */
113 void qdict_put_obj(QDict *qdict, const char *key, QObject *value)
114 {
115 unsigned int bucket;
116 QDictEntry *entry;
117
118 bucket = tdb_hash(key) % QDICT_BUCKET_MAX;
119 entry = qdict_find(qdict, key, bucket);
120 if (entry) {
121 /* replace key's value */
122 qobject_unref(entry->value);
123 entry->value = value;
124 } else {
125 /* allocate a new entry */
126 entry = alloc_entry(key, value);
127 QLIST_INSERT_HEAD(&qdict->table[bucket], entry, next);
128 qdict->size++;
129 }
130 }
131
132 void qdict_put_int(QDict *qdict, const char *key, int64_t value)
133 {
134 qdict_put(qdict, key, qnum_from_int(value));
135 }
136
137 void qdict_put_bool(QDict *qdict, const char *key, bool value)
138 {
139 qdict_put(qdict, key, qbool_from_bool(value));
140 }
141
142 void qdict_put_str(QDict *qdict, const char *key, const char *value)
143 {
144 qdict_put(qdict, key, qstring_from_str(value));
145 }
146
147 void qdict_put_null(QDict *qdict, const char *key)
148 {
149 qdict_put(qdict, key, qnull());
150 }
151
152 /**
153 * qdict_get(): Lookup for a given 'key'
154 *
155 * Return a weak reference to the QObject associated with 'key' if
156 * 'key' is present in the dictionary, NULL otherwise.
157 */
158 QObject *qdict_get(const QDict *qdict, const char *key)
159 {
160 QDictEntry *entry;
161
162 entry = qdict_find(qdict, key, tdb_hash(key) % QDICT_BUCKET_MAX);
163 return (entry == NULL ? NULL : entry->value);
164 }
165
166 /**
167 * qdict_haskey(): Check if 'key' exists
168 *
169 * Return 1 if 'key' exists in the dict, 0 otherwise
170 */
171 int qdict_haskey(const QDict *qdict, const char *key)
172 {
173 unsigned int bucket = tdb_hash(key) % QDICT_BUCKET_MAX;
174 return (qdict_find(qdict, key, bucket) == NULL ? 0 : 1);
175 }
176
177 /**
178 * qdict_size(): Return the size of the dictionary
179 */
180 size_t qdict_size(const QDict *qdict)
181 {
182 return qdict->size;
183 }
184
185 /**
186 * qdict_get_double(): Get an number mapped by 'key'
187 *
188 * This function assumes that 'key' exists and it stores a QNum.
189 *
190 * Return number mapped by 'key'.
191 */
192 double qdict_get_double(const QDict *qdict, const char *key)
193 {
194 return qnum_get_double(qobject_to(QNum, qdict_get(qdict, key)));
195 }
196
197 /**
198 * qdict_get_int(): Get an integer mapped by 'key'
199 *
200 * This function assumes that 'key' exists and it stores a
201 * QNum representable as int.
202 *
203 * Return integer mapped by 'key'.
204 */
205 int64_t qdict_get_int(const QDict *qdict, const char *key)
206 {
207 return qnum_get_int(qobject_to(QNum, qdict_get(qdict, key)));
208 }
209
210 /**
211 * qdict_get_bool(): Get a bool mapped by 'key'
212 *
213 * This function assumes that 'key' exists and it stores a
214 * QBool object.
215 *
216 * Return bool mapped by 'key'.
217 */
218 bool qdict_get_bool(const QDict *qdict, const char *key)
219 {
220 return qbool_get_bool(qobject_to(QBool, qdict_get(qdict, key)));
221 }
222
223 /**
224 * qdict_get_qlist(): If @qdict maps @key to a QList, return it, else NULL.
225 */
226 QList *qdict_get_qlist(const QDict *qdict, const char *key)
227 {
228 return qobject_to(QList, qdict_get(qdict, key));
229 }
230
231 /**
232 * qdict_get_qdict(): If @qdict maps @key to a QDict, return it, else NULL.
233 */
234 QDict *qdict_get_qdict(const QDict *qdict, const char *key)
235 {
236 return qobject_to(QDict, qdict_get(qdict, key));
237 }
238
239 /**
240 * qdict_get_str(): Get a pointer to the stored string mapped
241 * by 'key'
242 *
243 * This function assumes that 'key' exists and it stores a
244 * QString object.
245 *
246 * Return pointer to the string mapped by 'key'.
247 */
248 const char *qdict_get_str(const QDict *qdict, const char *key)
249 {
250 return qstring_get_str(qobject_to(QString, qdict_get(qdict, key)));
251 }
252
253 /**
254 * qdict_get_try_int(): Try to get integer mapped by 'key'
255 *
256 * Return integer mapped by 'key', if it is not present in the
257 * dictionary or if the stored object is not a QNum representing an
258 * integer, 'def_value' will be returned.
259 */
260 int64_t qdict_get_try_int(const QDict *qdict, const char *key,
261 int64_t def_value)
262 {
263 QNum *qnum = qobject_to(QNum, qdict_get(qdict, key));
264 int64_t val;
265
266 if (!qnum || !qnum_get_try_int(qnum, &val)) {
267 return def_value;
268 }
269
270 return val;
271 }
272
273 /**
274 * qdict_get_try_bool(): Try to get a bool mapped by 'key'
275 *
276 * Return bool mapped by 'key', if it is not present in the
277 * dictionary or if the stored object is not of QBool type
278 * 'def_value' will be returned.
279 */
280 bool qdict_get_try_bool(const QDict *qdict, const char *key, bool def_value)
281 {
282 QBool *qbool = qobject_to(QBool, qdict_get(qdict, key));
283
284 return qbool ? qbool_get_bool(qbool) : def_value;
285 }
286
287 /**
288 * qdict_get_try_str(): Try to get a pointer to the stored string
289 * mapped by 'key'
290 *
291 * Return a pointer to the string mapped by 'key', if it is not present
292 * in the dictionary or if the stored object is not of QString type
293 * NULL will be returned.
294 */
295 const char *qdict_get_try_str(const QDict *qdict, const char *key)
296 {
297 QString *qstr = qobject_to(QString, qdict_get(qdict, key));
298
299 return qstr ? qstring_get_str(qstr) : NULL;
300 }
301
302 static QDictEntry *qdict_next_entry(const QDict *qdict, int first_bucket)
303 {
304 int i;
305
306 for (i = first_bucket; i < QDICT_BUCKET_MAX; i++) {
307 if (!QLIST_EMPTY(&qdict->table[i])) {
308 return QLIST_FIRST(&qdict->table[i]);
309 }
310 }
311
312 return NULL;
313 }
314
315 /**
316 * qdict_first(): Return first qdict entry for iteration.
317 */
318 const QDictEntry *qdict_first(const QDict *qdict)
319 {
320 return qdict_next_entry(qdict, 0);
321 }
322
323 /**
324 * qdict_next(): Return next qdict entry in an iteration.
325 */
326 const QDictEntry *qdict_next(const QDict *qdict, const QDictEntry *entry)
327 {
328 QDictEntry *ret;
329
330 ret = QLIST_NEXT(entry, next);
331 if (!ret) {
332 unsigned int bucket = tdb_hash(entry->key) % QDICT_BUCKET_MAX;
333 ret = qdict_next_entry(qdict, bucket + 1);
334 }
335
336 return ret;
337 }
338
339 /**
340 * qdict_clone_shallow(): Clones a given QDict. Its entries are not copied, but
341 * another reference is added.
342 */
343 QDict *qdict_clone_shallow(const QDict *src)
344 {
345 QDict *dest;
346 QDictEntry *entry;
347 int i;
348
349 dest = qdict_new();
350
351 for (i = 0; i < QDICT_BUCKET_MAX; i++) {
352 QLIST_FOREACH(entry, &src->table[i], next) {
353 qdict_put_obj(dest, entry->key, qobject_ref(entry->value));
354 }
355 }
356
357 return dest;
358 }
359
360 /**
361 * qentry_destroy(): Free all the memory allocated by a QDictEntry
362 */
363 static void qentry_destroy(QDictEntry *e)
364 {
365 assert(e != NULL);
366 assert(e->key != NULL);
367 assert(e->value != NULL);
368
369 qobject_unref(e->value);
370 g_free(e->key);
371 g_free(e);
372 }
373
374 /**
375 * qdict_del(): Delete a 'key:value' pair from the dictionary
376 *
377 * This will destroy all data allocated by this entry.
378 */
379 void qdict_del(QDict *qdict, const char *key)
380 {
381 QDictEntry *entry;
382
383 entry = qdict_find(qdict, key, tdb_hash(key) % QDICT_BUCKET_MAX);
384 if (entry) {
385 QLIST_REMOVE(entry, next);
386 qentry_destroy(entry);
387 qdict->size--;
388 }
389 }
390
391 /**
392 * qdict_is_equal(): Test whether the two QDicts are equal
393 *
394 * Here, equality means whether they contain the same keys and whether
395 * the respective values are in turn equal (i.e. invoking
396 * qobject_is_equal() on them yields true).
397 */
398 bool qdict_is_equal(const QObject *x, const QObject *y)
399 {
400 const QDict *dict_x = qobject_to(QDict, x);
401 const QDict *dict_y = qobject_to(QDict, y);
402 const QDictEntry *e;
403
404 if (qdict_size(dict_x) != qdict_size(dict_y)) {
405 return false;
406 }
407
408 for (e = qdict_first(dict_x); e; e = qdict_next(dict_x, e)) {
409 const QObject *obj_x = qdict_entry_value(e);
410 const QObject *obj_y = qdict_get(dict_y, qdict_entry_key(e));
411
412 if (!qobject_is_equal(obj_x, obj_y)) {
413 return false;
414 }
415 }
416
417 return true;
418 }
419
420 /**
421 * qdict_destroy_obj(): Free all the memory allocated by a QDict
422 */
423 void qdict_destroy_obj(QObject *obj)
424 {
425 int i;
426 QDict *qdict;
427
428 assert(obj != NULL);
429 qdict = qobject_to(QDict, obj);
430
431 for (i = 0; i < QDICT_BUCKET_MAX; i++) {
432 QDictEntry *entry = QLIST_FIRST(&qdict->table[i]);
433 while (entry) {
434 QDictEntry *tmp = QLIST_NEXT(entry, next);
435 QLIST_REMOVE(entry, next);
436 qentry_destroy(entry);
437 entry = tmp;
438 }
439 }
440
441 g_free(qdict);
442 }