qdict: implement a qdict_crumple method for un-flattening a dict
[qemu/armbru.git] / qobject / qdict.c
blob197b0fbd47f23707eb201f004485c4e541067435
1 /*
2 * QDict Module
4 * Copyright (C) 2009 Red Hat Inc.
6 * Authors:
7 * Luiz Capitulino <lcapitulino@redhat.com>
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.
13 #include "qemu/osdep.h"
14 #include "qapi/qmp/qint.h"
15 #include "qapi/qmp/qfloat.h"
16 #include "qapi/qmp/qdict.h"
17 #include "qapi/qmp/qbool.h"
18 #include "qapi/qmp/qstring.h"
19 #include "qapi/qmp/qobject.h"
20 #include "qapi/error.h"
21 #include "qemu/queue.h"
22 #include "qemu-common.h"
23 #include "qemu/cutils.h"
25 /**
26 * qdict_new(): Create a new QDict
28 * Return strong reference.
30 QDict *qdict_new(void)
32 QDict *qdict;
34 qdict = g_malloc0(sizeof(*qdict));
35 qobject_init(QOBJECT(qdict), QTYPE_QDICT);
37 return qdict;
40 /**
41 * qobject_to_qdict(): Convert a QObject into a QDict
43 QDict *qobject_to_qdict(const QObject *obj)
45 if (!obj || qobject_type(obj) != QTYPE_QDICT) {
46 return NULL;
48 return container_of(obj, QDict, base);
51 /**
52 * tdb_hash(): based on the hash agorithm from gdbm, via tdb
53 * (from module-init-tools)
55 static unsigned int tdb_hash(const char *name)
57 unsigned value; /* Used to compute the hash value. */
58 unsigned i; /* Used to cycle through random values. */
60 /* Set the initial value from the key size. */
61 for (value = 0x238F13AF * strlen(name), i=0; name[i]; i++)
62 value = (value + (((const unsigned char *)name)[i] << (i*5 % 24)));
64 return (1103515243 * value + 12345);
67 /**
68 * alloc_entry(): allocate a new QDictEntry
70 static QDictEntry *alloc_entry(const char *key, QObject *value)
72 QDictEntry *entry;
74 entry = g_malloc0(sizeof(*entry));
75 entry->key = g_strdup(key);
76 entry->value = value;
78 return entry;
81 /**
82 * qdict_entry_value(): Return qdict entry value
84 * Return weak reference.
86 QObject *qdict_entry_value(const QDictEntry *entry)
88 return entry->value;
91 /**
92 * qdict_entry_key(): Return qdict entry key
94 * Return a *pointer* to the string, it has to be duplicated before being
95 * stored.
97 const char *qdict_entry_key(const QDictEntry *entry)
99 return entry->key;
103 * qdict_find(): List lookup function
105 static QDictEntry *qdict_find(const QDict *qdict,
106 const char *key, unsigned int bucket)
108 QDictEntry *entry;
110 QLIST_FOREACH(entry, &qdict->table[bucket], next)
111 if (!strcmp(entry->key, key))
112 return entry;
114 return NULL;
118 * qdict_put_obj(): Put a new QObject into the dictionary
120 * Insert the pair 'key:value' into 'qdict', if 'key' already exists
121 * its 'value' will be replaced.
123 * This is done by freeing the reference to the stored QObject and
124 * storing the new one in the same entry.
126 * NOTE: ownership of 'value' is transferred to the QDict
128 void qdict_put_obj(QDict *qdict, const char *key, QObject *value)
130 unsigned int bucket;
131 QDictEntry *entry;
133 bucket = tdb_hash(key) % QDICT_BUCKET_MAX;
134 entry = qdict_find(qdict, key, bucket);
135 if (entry) {
136 /* replace key's value */
137 qobject_decref(entry->value);
138 entry->value = value;
139 } else {
140 /* allocate a new entry */
141 entry = alloc_entry(key, value);
142 QLIST_INSERT_HEAD(&qdict->table[bucket], entry, next);
143 qdict->size++;
148 * qdict_get(): Lookup for a given 'key'
150 * Return a weak reference to the QObject associated with 'key' if
151 * 'key' is present in the dictionary, NULL otherwise.
153 QObject *qdict_get(const QDict *qdict, const char *key)
155 QDictEntry *entry;
157 entry = qdict_find(qdict, key, tdb_hash(key) % QDICT_BUCKET_MAX);
158 return (entry == NULL ? NULL : entry->value);
162 * qdict_haskey(): Check if 'key' exists
164 * Return 1 if 'key' exists in the dict, 0 otherwise
166 int qdict_haskey(const QDict *qdict, const char *key)
168 unsigned int bucket = tdb_hash(key) % QDICT_BUCKET_MAX;
169 return (qdict_find(qdict, key, bucket) == NULL ? 0 : 1);
173 * qdict_size(): Return the size of the dictionary
175 size_t qdict_size(const QDict *qdict)
177 return qdict->size;
181 * qdict_get_obj(): Get a QObject of a specific type
183 static QObject *qdict_get_obj(const QDict *qdict, const char *key, QType type)
185 QObject *obj;
187 obj = qdict_get(qdict, key);
188 assert(obj != NULL);
189 assert(qobject_type(obj) == type);
191 return obj;
195 * qdict_get_double(): Get an number mapped by 'key'
197 * This function assumes that 'key' exists and it stores a
198 * QFloat or QInt object.
200 * Return number mapped by 'key'.
202 double qdict_get_double(const QDict *qdict, const char *key)
204 QObject *obj = qdict_get(qdict, key);
206 assert(obj);
207 switch (qobject_type(obj)) {
208 case QTYPE_QFLOAT:
209 return qfloat_get_double(qobject_to_qfloat(obj));
210 case QTYPE_QINT:
211 return qint_get_int(qobject_to_qint(obj));
212 default:
213 abort();
218 * qdict_get_int(): Get an integer mapped by 'key'
220 * This function assumes that 'key' exists and it stores a
221 * QInt object.
223 * Return integer mapped by 'key'.
225 int64_t qdict_get_int(const QDict *qdict, const char *key)
227 return qint_get_int(qobject_to_qint(qdict_get(qdict, key)));
231 * qdict_get_bool(): Get a bool mapped by 'key'
233 * This function assumes that 'key' exists and it stores a
234 * QBool object.
236 * Return bool mapped by 'key'.
238 bool qdict_get_bool(const QDict *qdict, const char *key)
240 return qbool_get_bool(qobject_to_qbool(qdict_get(qdict, key)));
244 * qdict_get_qlist(): Get the QList mapped by 'key'
246 * This function assumes that 'key' exists and it stores a
247 * QList object.
249 * Return QList mapped by 'key'.
251 QList *qdict_get_qlist(const QDict *qdict, const char *key)
253 return qobject_to_qlist(qdict_get_obj(qdict, key, QTYPE_QLIST));
257 * qdict_get_qdict(): Get the QDict mapped by 'key'
259 * This function assumes that 'key' exists and it stores a
260 * QDict object.
262 * Return QDict mapped by 'key'.
264 QDict *qdict_get_qdict(const QDict *qdict, const char *key)
266 return qobject_to_qdict(qdict_get(qdict, key));
270 * qdict_get_str(): Get a pointer to the stored string mapped
271 * by 'key'
273 * This function assumes that 'key' exists and it stores a
274 * QString object.
276 * Return pointer to the string mapped by 'key'.
278 const char *qdict_get_str(const QDict *qdict, const char *key)
280 return qstring_get_str(qobject_to_qstring(qdict_get(qdict, key)));
284 * qdict_get_try_int(): Try to get integer mapped by 'key'
286 * Return integer mapped by 'key', if it is not present in
287 * the dictionary or if the stored object is not of QInt type
288 * 'def_value' will be returned.
290 int64_t qdict_get_try_int(const QDict *qdict, const char *key,
291 int64_t def_value)
293 QInt *qint = qobject_to_qint(qdict_get(qdict, key));
295 return qint ? qint_get_int(qint) : def_value;
299 * qdict_get_try_bool(): Try to get a bool mapped by 'key'
301 * Return bool mapped by 'key', if it is not present in the
302 * dictionary or if the stored object is not of QBool type
303 * 'def_value' will be returned.
305 bool qdict_get_try_bool(const QDict *qdict, const char *key, bool def_value)
307 QBool *qbool = qobject_to_qbool(qdict_get(qdict, key));
309 return qbool ? qbool_get_bool(qbool) : def_value;
313 * qdict_get_try_str(): Try to get a pointer to the stored string
314 * mapped by 'key'
316 * Return a pointer to the string mapped by 'key', if it is not present
317 * in the dictionary or if the stored object is not of QString type
318 * NULL will be returned.
320 const char *qdict_get_try_str(const QDict *qdict, const char *key)
322 QString *qstr = qobject_to_qstring(qdict_get(qdict, key));
324 return qstr ? qstring_get_str(qstr) : NULL;
328 * qdict_iter(): Iterate over all the dictionary's stored values.
330 * This function allows the user to provide an iterator, which will be
331 * called for each stored value in the dictionary.
333 void qdict_iter(const QDict *qdict,
334 void (*iter)(const char *key, QObject *obj, void *opaque),
335 void *opaque)
337 int i;
338 QDictEntry *entry;
340 for (i = 0; i < QDICT_BUCKET_MAX; i++) {
341 QLIST_FOREACH(entry, &qdict->table[i], next)
342 iter(entry->key, entry->value, opaque);
346 static QDictEntry *qdict_next_entry(const QDict *qdict, int first_bucket)
348 int i;
350 for (i = first_bucket; i < QDICT_BUCKET_MAX; i++) {
351 if (!QLIST_EMPTY(&qdict->table[i])) {
352 return QLIST_FIRST(&qdict->table[i]);
356 return NULL;
360 * qdict_first(): Return first qdict entry for iteration.
362 const QDictEntry *qdict_first(const QDict *qdict)
364 return qdict_next_entry(qdict, 0);
368 * qdict_next(): Return next qdict entry in an iteration.
370 const QDictEntry *qdict_next(const QDict *qdict, const QDictEntry *entry)
372 QDictEntry *ret;
374 ret = QLIST_NEXT(entry, next);
375 if (!ret) {
376 unsigned int bucket = tdb_hash(entry->key) % QDICT_BUCKET_MAX;
377 ret = qdict_next_entry(qdict, bucket + 1);
380 return ret;
384 * qdict_clone_shallow(): Clones a given QDict. Its entries are not copied, but
385 * another reference is added.
387 QDict *qdict_clone_shallow(const QDict *src)
389 QDict *dest;
390 QDictEntry *entry;
391 int i;
393 dest = qdict_new();
395 for (i = 0; i < QDICT_BUCKET_MAX; i++) {
396 QLIST_FOREACH(entry, &src->table[i], next) {
397 qobject_incref(entry->value);
398 qdict_put_obj(dest, entry->key, entry->value);
402 return dest;
406 * qentry_destroy(): Free all the memory allocated by a QDictEntry
408 static void qentry_destroy(QDictEntry *e)
410 assert(e != NULL);
411 assert(e->key != NULL);
412 assert(e->value != NULL);
414 qobject_decref(e->value);
415 g_free(e->key);
416 g_free(e);
420 * qdict_del(): Delete a 'key:value' pair from the dictionary
422 * This will destroy all data allocated by this entry.
424 void qdict_del(QDict *qdict, const char *key)
426 QDictEntry *entry;
428 entry = qdict_find(qdict, key, tdb_hash(key) % QDICT_BUCKET_MAX);
429 if (entry) {
430 QLIST_REMOVE(entry, next);
431 qentry_destroy(entry);
432 qdict->size--;
437 * qdict_destroy_obj(): Free all the memory allocated by a QDict
439 void qdict_destroy_obj(QObject *obj)
441 int i;
442 QDict *qdict;
444 assert(obj != NULL);
445 qdict = qobject_to_qdict(obj);
447 for (i = 0; i < QDICT_BUCKET_MAX; i++) {
448 QDictEntry *entry = QLIST_FIRST(&qdict->table[i]);
449 while (entry) {
450 QDictEntry *tmp = QLIST_NEXT(entry, next);
451 QLIST_REMOVE(entry, next);
452 qentry_destroy(entry);
453 entry = tmp;
457 g_free(qdict);
461 * qdict_copy_default(): If no entry mapped by 'key' exists in 'dst' yet, the
462 * value of 'key' in 'src' is copied there (and the refcount increased
463 * accordingly).
465 void qdict_copy_default(QDict *dst, QDict *src, const char *key)
467 QObject *val;
469 if (qdict_haskey(dst, key)) {
470 return;
473 val = qdict_get(src, key);
474 if (val) {
475 qobject_incref(val);
476 qdict_put_obj(dst, key, val);
481 * qdict_set_default_str(): If no entry mapped by 'key' exists in 'dst' yet, a
482 * new QString initialised by 'val' is put there.
484 void qdict_set_default_str(QDict *dst, const char *key, const char *val)
486 if (qdict_haskey(dst, key)) {
487 return;
490 qdict_put(dst, key, qstring_from_str(val));
493 static void qdict_flatten_qdict(QDict *qdict, QDict *target,
494 const char *prefix);
496 static void qdict_flatten_qlist(QList *qlist, QDict *target, const char *prefix)
498 QObject *value;
499 const QListEntry *entry;
500 char *new_key;
501 int i;
503 /* This function is never called with prefix == NULL, i.e., it is always
504 * called from within qdict_flatten_q(list|dict)(). Therefore, it does not
505 * need to remove list entries during the iteration (the whole list will be
506 * deleted eventually anyway from qdict_flatten_qdict()). */
507 assert(prefix);
509 entry = qlist_first(qlist);
511 for (i = 0; entry; entry = qlist_next(entry), i++) {
512 value = qlist_entry_obj(entry);
513 new_key = g_strdup_printf("%s.%i", prefix, i);
515 if (qobject_type(value) == QTYPE_QDICT) {
516 qdict_flatten_qdict(qobject_to_qdict(value), target, new_key);
517 } else if (qobject_type(value) == QTYPE_QLIST) {
518 qdict_flatten_qlist(qobject_to_qlist(value), target, new_key);
519 } else {
520 /* All other types are moved to the target unchanged. */
521 qobject_incref(value);
522 qdict_put_obj(target, new_key, value);
525 g_free(new_key);
529 static void qdict_flatten_qdict(QDict *qdict, QDict *target, const char *prefix)
531 QObject *value;
532 const QDictEntry *entry, *next;
533 char *new_key;
534 bool delete;
536 entry = qdict_first(qdict);
538 while (entry != NULL) {
540 next = qdict_next(qdict, entry);
541 value = qdict_entry_value(entry);
542 new_key = NULL;
543 delete = false;
545 if (prefix) {
546 new_key = g_strdup_printf("%s.%s", prefix, entry->key);
549 if (qobject_type(value) == QTYPE_QDICT) {
550 /* Entries of QDicts are processed recursively, the QDict object
551 * itself disappears. */
552 qdict_flatten_qdict(qobject_to_qdict(value), target,
553 new_key ? new_key : entry->key);
554 delete = true;
555 } else if (qobject_type(value) == QTYPE_QLIST) {
556 qdict_flatten_qlist(qobject_to_qlist(value), target,
557 new_key ? new_key : entry->key);
558 delete = true;
559 } else if (prefix) {
560 /* All other objects are moved to the target unchanged. */
561 qobject_incref(value);
562 qdict_put_obj(target, new_key, value);
563 delete = true;
566 g_free(new_key);
568 if (delete) {
569 qdict_del(qdict, entry->key);
571 /* Restart loop after modifying the iterated QDict */
572 entry = qdict_first(qdict);
573 continue;
576 entry = next;
581 * qdict_flatten(): For each nested QDict with key x, all fields with key y
582 * are moved to this QDict and their key is renamed to "x.y". For each nested
583 * QList with key x, the field at index y is moved to this QDict with the key
584 * "x.y" (i.e., the reverse of what qdict_array_split() does).
585 * This operation is applied recursively for nested QDicts and QLists.
587 void qdict_flatten(QDict *qdict)
589 qdict_flatten_qdict(qdict, qdict, NULL);
592 /* extract all the src QDict entries starting by start into dst */
593 void qdict_extract_subqdict(QDict *src, QDict **dst, const char *start)
596 const QDictEntry *entry, *next;
597 const char *p;
599 *dst = qdict_new();
600 entry = qdict_first(src);
602 while (entry != NULL) {
603 next = qdict_next(src, entry);
604 if (strstart(entry->key, start, &p)) {
605 qobject_incref(entry->value);
606 qdict_put_obj(*dst, p, entry->value);
607 qdict_del(src, entry->key);
609 entry = next;
613 static int qdict_count_prefixed_entries(const QDict *src, const char *start)
615 const QDictEntry *entry;
616 int count = 0;
618 for (entry = qdict_first(src); entry; entry = qdict_next(src, entry)) {
619 if (strstart(entry->key, start, NULL)) {
620 if (count == INT_MAX) {
621 return -ERANGE;
623 count++;
627 return count;
631 * qdict_array_split(): This function moves array-like elements of a QDict into
632 * a new QList. Every entry in the original QDict with a key "%u" or one
633 * prefixed "%u.", where %u designates an unsigned integer starting at 0 and
634 * incrementally counting up, will be moved to a new QDict at index %u in the
635 * output QList with the key prefix removed, if that prefix is "%u.". If the
636 * whole key is just "%u", the whole QObject will be moved unchanged without
637 * creating a new QDict. The function terminates when there is no entry in the
638 * QDict with a prefix directly (incrementally) following the last one; it also
639 * returns if there are both entries with "%u" and "%u." for the same index %u.
640 * Example: {"0.a": 42, "0.b": 23, "1.x": 0, "4.y": 1, "o.o": 7, "2": 66}
641 * (or {"1.x": 0, "4.y": 1, "0.a": 42, "o.o": 7, "0.b": 23, "2": 66})
642 * => [{"a": 42, "b": 23}, {"x": 0}, 66]
643 * and {"4.y": 1, "o.o": 7} (remainder of the old QDict)
645 void qdict_array_split(QDict *src, QList **dst)
647 unsigned i;
649 *dst = qlist_new();
651 for (i = 0; i < UINT_MAX; i++) {
652 QObject *subqobj;
653 bool is_subqdict;
654 QDict *subqdict;
655 char indexstr[32], prefix[32];
656 size_t snprintf_ret;
658 snprintf_ret = snprintf(indexstr, 32, "%u", i);
659 assert(snprintf_ret < 32);
661 subqobj = qdict_get(src, indexstr);
663 snprintf_ret = snprintf(prefix, 32, "%u.", i);
664 assert(snprintf_ret < 32);
666 /* Overflow is the same as positive non-zero results */
667 is_subqdict = qdict_count_prefixed_entries(src, prefix);
669 // There may be either a single subordinate object (named "%u") or
670 // multiple objects (each with a key prefixed "%u."), but not both.
671 if (!subqobj == !is_subqdict) {
672 break;
675 if (is_subqdict) {
676 qdict_extract_subqdict(src, &subqdict, prefix);
677 assert(qdict_size(subqdict) > 0);
678 } else {
679 qobject_incref(subqobj);
680 qdict_del(src, indexstr);
683 qlist_append_obj(*dst, subqobj ?: QOBJECT(subqdict));
688 * qdict_split_flat_key:
689 * @key: the key string to split
690 * @prefix: non-NULL pointer to hold extracted prefix
691 * @suffix: non-NULL pointer to remaining suffix
693 * Given a flattened key such as 'foo.0.bar', split it into two parts
694 * at the first '.' separator. Allows double dot ('..') to escape the
695 * normal separator.
697 * e.g.
698 * 'foo.0.bar' -> prefix='foo' and suffix='0.bar'
699 * 'foo..0.bar' -> prefix='foo.0' and suffix='bar'
701 * The '..' sequence will be unescaped in the returned 'prefix'
702 * string. The 'suffix' string will be left in escaped format, so it
703 * can be fed back into the qdict_split_flat_key() key as the input
704 * later.
706 * The caller is responsible for freeing the string returned in @prefix
707 * using g_free().
709 static void qdict_split_flat_key(const char *key, char **prefix,
710 const char **suffix)
712 const char *separator;
713 size_t i, j;
715 /* Find first '.' separator, but if there is a pair '..'
716 * that acts as an escape, so skip over '..' */
717 separator = NULL;
718 do {
719 if (separator) {
720 separator += 2;
721 } else {
722 separator = key;
724 separator = strchr(separator, '.');
725 } while (separator && separator[1] == '.');
727 if (separator) {
728 *prefix = g_strndup(key, separator - key);
729 *suffix = separator + 1;
730 } else {
731 *prefix = g_strdup(key);
732 *suffix = NULL;
735 /* Unescape the '..' sequence into '.' */
736 for (i = 0, j = 0; (*prefix)[i] != '\0'; i++, j++) {
737 if ((*prefix)[i] == '.') {
738 assert((*prefix)[i + 1] == '.');
739 i++;
741 (*prefix)[j] = (*prefix)[i];
743 (*prefix)[j] = '\0';
747 * qdict_is_list:
748 * @maybe_list: dict to check if keys represent list elements.
750 * Determine whether all keys in @maybe_list are valid list elements.
751 * If @maybe_list is non-zero in length and all the keys look like
752 * valid list indexes, this will return 1. If @maybe_list is zero
753 * length or all keys are non-numeric then it will return 0 to indicate
754 * it is a normal qdict. If there is a mix of numeric and non-numeric
755 * keys, or the list indexes are non-contiguous, an error is reported.
757 * Returns: 1 if a valid list, 0 if a dict, -1 on error
759 static int qdict_is_list(QDict *maybe_list, Error **errp)
761 const QDictEntry *ent;
762 ssize_t len = 0;
763 ssize_t max = -1;
764 int is_list = -1;
765 int64_t val;
767 for (ent = qdict_first(maybe_list); ent != NULL;
768 ent = qdict_next(maybe_list, ent)) {
770 if (qemu_strtoll(ent->key, NULL, 10, &val) == 0) {
771 if (is_list == -1) {
772 is_list = 1;
773 } else if (!is_list) {
774 error_setg(errp,
775 "Cannot mix list and non-list keys");
776 return -1;
778 len++;
779 if (val > max) {
780 max = val;
782 } else {
783 if (is_list == -1) {
784 is_list = 0;
785 } else if (is_list) {
786 error_setg(errp,
787 "Cannot mix list and non-list keys");
788 return -1;
793 if (is_list == -1) {
794 assert(!qdict_size(maybe_list));
795 is_list = 0;
798 /* NB this isn't a perfect check - e.g. it won't catch
799 * a list containing '1', '+1', '01', '3', but that
800 * does not matter - we've still proved that the
801 * input is a list. It is up the caller to do a
802 * stricter check if desired */
803 if (len != (max + 1)) {
804 error_setg(errp, "List indices are not contiguous, "
805 "saw %zd elements but %zd largest index",
806 len, max);
807 return -1;
810 return is_list;
814 * qdict_crumple:
815 * @src: the original flat dictionary (only scalar values) to crumple
817 * Takes a flat dictionary whose keys use '.' separator to indicate
818 * nesting, and values are scalars, and crumples it into a nested
819 * structure.
821 * To include a literal '.' in a key name, it must be escaped as '..'
823 * For example, an input of:
825 * { 'foo.0.bar': 'one', 'foo.0.wizz': '1',
826 * 'foo.1.bar': 'two', 'foo.1.wizz': '2' }
828 * will result in an output of:
831 * 'foo': [
832 * { 'bar': 'one', 'wizz': '1' },
833 * { 'bar': 'two', 'wizz': '2' }
834 * ],
837 * The following scenarios in the input dict will result in an
838 * error being returned:
840 * - Any values in @src are non-scalar types
841 * - If keys in @src imply that a particular level is both a
842 * list and a dict. e.g., "foo.0.bar" and "foo.eek.bar".
843 * - If keys in @src imply that a particular level is a list,
844 * but the indices are non-contiguous. e.g. "foo.0.bar" and
845 * "foo.2.bar" without any "foo.1.bar" present.
846 * - If keys in @src represent list indexes, but are not in
847 * the "%zu" format. e.g. "foo.+0.bar"
849 * Returns: either a QDict or QList for the nested data structure, or NULL
850 * on error
852 QObject *qdict_crumple(const QDict *src, Error **errp)
854 const QDictEntry *ent;
855 QDict *two_level, *multi_level = NULL;
856 QObject *dst = NULL, *child;
857 size_t i;
858 char *prefix = NULL;
859 const char *suffix = NULL;
860 int is_list;
862 two_level = qdict_new();
864 /* Step 1: split our totally flat dict into a two level dict */
865 for (ent = qdict_first(src); ent != NULL; ent = qdict_next(src, ent)) {
866 if (qobject_type(ent->value) == QTYPE_QDICT ||
867 qobject_type(ent->value) == QTYPE_QLIST) {
868 error_setg(errp, "Value %s is not a scalar",
869 ent->key);
870 goto error;
873 qdict_split_flat_key(ent->key, &prefix, &suffix);
875 child = qdict_get(two_level, prefix);
876 if (suffix) {
877 if (child) {
878 if (qobject_type(child) != QTYPE_QDICT) {
879 error_setg(errp, "Key %s prefix is already set as a scalar",
880 prefix);
881 goto error;
883 } else {
884 child = QOBJECT(qdict_new());
885 qdict_put_obj(two_level, prefix, child);
887 qobject_incref(ent->value);
888 qdict_put_obj(qobject_to_qdict(child), suffix, ent->value);
889 } else {
890 if (child) {
891 error_setg(errp, "Key %s prefix is already set as a dict",
892 prefix);
893 goto error;
895 qobject_incref(ent->value);
896 qdict_put_obj(two_level, prefix, ent->value);
899 g_free(prefix);
900 prefix = NULL;
903 /* Step 2: optionally process the two level dict recursively
904 * into a multi-level dict */
905 multi_level = qdict_new();
906 for (ent = qdict_first(two_level); ent != NULL;
907 ent = qdict_next(two_level, ent)) {
909 if (qobject_type(ent->value) == QTYPE_QDICT) {
910 child = qdict_crumple(qobject_to_qdict(ent->value), errp);
911 if (!child) {
912 goto error;
915 qdict_put_obj(multi_level, ent->key, child);
916 } else {
917 qobject_incref(ent->value);
918 qdict_put_obj(multi_level, ent->key, ent->value);
921 QDECREF(two_level);
922 two_level = NULL;
924 /* Step 3: detect if we need to turn our dict into list */
925 is_list = qdict_is_list(multi_level, errp);
926 if (is_list < 0) {
927 goto error;
930 if (is_list) {
931 dst = QOBJECT(qlist_new());
933 for (i = 0; i < qdict_size(multi_level); i++) {
934 char *key = g_strdup_printf("%zu", i);
936 child = qdict_get(multi_level, key);
937 g_free(key);
939 if (!child) {
940 error_setg(errp, "Missing list index %zu", i);
941 goto error;
944 qobject_incref(child);
945 qlist_append_obj(qobject_to_qlist(dst), child);
947 QDECREF(multi_level);
948 multi_level = NULL;
949 } else {
950 dst = QOBJECT(multi_level);
953 return dst;
955 error:
956 g_free(prefix);
957 QDECREF(multi_level);
958 QDECREF(two_level);
959 qobject_decref(dst);
960 return NULL;
964 * qdict_array_entries(): Returns the number of direct array entries if the
965 * sub-QDict of src specified by the prefix in subqdict (or src itself for
966 * prefix == "") is valid as an array, i.e. the length of the created list if
967 * the sub-QDict would become empty after calling qdict_array_split() on it. If
968 * the array is not valid, -EINVAL is returned.
970 int qdict_array_entries(QDict *src, const char *subqdict)
972 const QDictEntry *entry;
973 unsigned i;
974 unsigned entries = 0;
975 size_t subqdict_len = strlen(subqdict);
977 assert(!subqdict_len || subqdict[subqdict_len - 1] == '.');
979 /* qdict_array_split() loops until UINT_MAX, but as we want to return
980 * negative errors, we only have a signed return value here. Any additional
981 * entries will lead to -EINVAL. */
982 for (i = 0; i < INT_MAX; i++) {
983 QObject *subqobj;
984 int subqdict_entries;
985 char *prefix = g_strdup_printf("%s%u.", subqdict, i);
987 subqdict_entries = qdict_count_prefixed_entries(src, prefix);
989 /* Remove ending "." */
990 prefix[strlen(prefix) - 1] = 0;
991 subqobj = qdict_get(src, prefix);
993 g_free(prefix);
995 if (subqdict_entries < 0) {
996 return subqdict_entries;
999 /* There may be either a single subordinate object (named "%u") or
1000 * multiple objects (each with a key prefixed "%u."), but not both. */
1001 if (subqobj && subqdict_entries) {
1002 return -EINVAL;
1003 } else if (!subqobj && !subqdict_entries) {
1004 break;
1007 entries += subqdict_entries ? subqdict_entries : 1;
1010 /* Consider everything handled that isn't part of the given sub-QDict */
1011 for (entry = qdict_first(src); entry; entry = qdict_next(src, entry)) {
1012 if (!strstart(qdict_entry_key(entry), subqdict, NULL)) {
1013 entries++;
1017 /* Anything left in the sub-QDict that wasn't handled? */
1018 if (qdict_size(src) != entries) {
1019 return -EINVAL;
1022 return i;
1026 * qdict_join(): Absorb the src QDict into the dest QDict, that is, move all
1027 * elements from src to dest.
1029 * If an element from src has a key already present in dest, it will not be
1030 * moved unless overwrite is true.
1032 * If overwrite is true, the conflicting values in dest will be discarded and
1033 * replaced by the corresponding values from src.
1035 * Therefore, with overwrite being true, the src QDict will always be empty when
1036 * this function returns. If overwrite is false, the src QDict will be empty
1037 * iff there were no conflicts.
1039 void qdict_join(QDict *dest, QDict *src, bool overwrite)
1041 const QDictEntry *entry, *next;
1043 entry = qdict_first(src);
1044 while (entry) {
1045 next = qdict_next(src, entry);
1047 if (overwrite || !qdict_haskey(dest, entry->key)) {
1048 qobject_incref(entry->value);
1049 qdict_put_obj(dest, entry->key, entry->value);
1050 qdict_del(src, entry->key);
1053 entry = next;