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/*
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 * QDict Module
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 *
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 * Copyright (C) 2009 Red Hat Inc.
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 *
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 * Authors:
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 *  Luiz Capitulino <lcapitulino@redhat.com>
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 *
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 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
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 * See the COPYING.LIB file in the top-level directory.
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 */
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#include "qapi/qmp/qint.h"
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#include "qapi/qmp/qfloat.h"
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#include "qapi/qmp/qdict.h"
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#include "qapi/qmp/qbool.h"
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#include "qapi/qmp/qstring.h"
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#include "qapi/qmp/qobject.h"
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#include "qemu/queue.h"
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#include "qemu-common.h"
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static void qdict_destroy_obj(QObject *obj);
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static const QType qdict_type = {
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    .code = QTYPE_QDICT,
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    .destroy = qdict_destroy_obj,
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};
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/**
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 * qdict_new(): Create a new QDict
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 *
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 * Return strong reference.
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 */
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QDict *qdict_new(void)
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{
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    QDict *qdict;
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    qdict = g_malloc0(sizeof(*qdict));
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    QOBJECT_INIT(qdict, &qdict_type);
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    return qdict;
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}
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/**
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 * qobject_to_qdict(): Convert a QObject into a QDict
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 */
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QDict *qobject_to_qdict(const QObject *obj)
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{
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    if (qobject_type(obj) != QTYPE_QDICT)
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        return NULL;
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    return container_of(obj, QDict, base);
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}
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/**
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 * tdb_hash(): based on the hash agorithm from gdbm, via tdb
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 * (from module-init-tools)
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 */
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static unsigned int tdb_hash(const char *name)
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{
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    unsigned value;        /* Used to compute the hash value.  */
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    unsigned   i;        /* Used to cycle through random values. */
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    /* Set the initial value from the key size. */
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    for (value = 0x238F13AF * strlen(name), i=0; name[i]; i++)
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        value = (value + (((const unsigned char *)name)[i] << (i*5 % 24)));
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    return (1103515243 * value + 12345);
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}
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/**
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 * alloc_entry(): allocate a new QDictEntry
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 */
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static QDictEntry *alloc_entry(const char *key, QObject *value)
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{
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    QDictEntry *entry;
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    entry = g_malloc0(sizeof(*entry));
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    entry->key = g_strdup(key);
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    entry->value = value;
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    return entry;
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}
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/**
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 * qdict_entry_value(): Return qdict entry value
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 *
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 * Return weak reference.
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 */
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QObject *qdict_entry_value(const QDictEntry *entry)
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{
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    return entry->value;
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}
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/**
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 * qdict_entry_key(): Return qdict entry key
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 *
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 * Return a *pointer* to the string, it has to be duplicated before being
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 * stored.
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 */
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const char *qdict_entry_key(const QDictEntry *entry)
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{
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    return entry->key;
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}
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/**
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 * qdict_find(): List lookup function
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 */
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static QDictEntry *qdict_find(const QDict *qdict,
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                              const char *key, unsigned int bucket)
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{
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    QDictEntry *entry;
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    QLIST_FOREACH(entry, &qdict->table[bucket], next)
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        if (!strcmp(entry->key, key))
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            return entry;
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    return NULL;
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}
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/**
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 * qdict_put_obj(): Put a new QObject into the dictionary
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 *
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 * Insert the pair 'key:value' into 'qdict', if 'key' already exists
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 * its 'value' will be replaced.
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 *
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 * This is done by freeing the reference to the stored QObject and
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 * storing the new one in the same entry.
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 *
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 * NOTE: ownership of 'value' is transferred to the QDict
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 */
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void qdict_put_obj(QDict *qdict, const char *key, QObject *value)
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{
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    unsigned int bucket;
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    QDictEntry *entry;
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    bucket = tdb_hash(key) % QDICT_BUCKET_MAX;
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    entry = qdict_find(qdict, key, bucket);
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    if (entry) {
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        /* replace key's value */
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        qobject_decref(entry->value);
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        entry->value = value;
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    } else {
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        /* allocate a new entry */
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        entry = alloc_entry(key, value);
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        QLIST_INSERT_HEAD(&qdict->table[bucket], entry, next);
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        qdict->size++;
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    }
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}
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/**
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 * qdict_get(): Lookup for a given 'key'
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 *
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 * Return a weak reference to the QObject associated with 'key' if
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 * 'key' is present in the dictionary, NULL otherwise.
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 */
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QObject *qdict_get(const QDict *qdict, const char *key)
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{
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    QDictEntry *entry;
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    entry = qdict_find(qdict, key, tdb_hash(key) % QDICT_BUCKET_MAX);
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    return (entry == NULL ? NULL : entry->value);
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}
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/**
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 * qdict_haskey(): Check if 'key' exists
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 *
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 * Return 1 if 'key' exists in the dict, 0 otherwise
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 */
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int qdict_haskey(const QDict *qdict, const char *key)
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{
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    unsigned int bucket = tdb_hash(key) % QDICT_BUCKET_MAX;
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    return (qdict_find(qdict, key, bucket) == NULL ? 0 : 1);
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}
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/**
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 * qdict_size(): Return the size of the dictionary
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 */
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size_t qdict_size(const QDict *qdict)
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{
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    return qdict->size;
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}
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/**
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 * qdict_get_obj(): Get a QObject of a specific type
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 */
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static QObject *qdict_get_obj(const QDict *qdict, const char *key,
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                              qtype_code type)
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{
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    QObject *obj;
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    obj = qdict_get(qdict, key);
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    assert(obj != NULL);
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    assert(qobject_type(obj) == type);
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    return obj;
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}
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/**
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 * qdict_get_double(): Get an number mapped by 'key'
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 *
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 * This function assumes that 'key' exists and it stores a
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 * QFloat or QInt object.
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 *
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 * Return number mapped by 'key'.
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 */
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double qdict_get_double(const QDict *qdict, const char *key)
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{
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    QObject *obj = qdict_get(qdict, key);
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    assert(obj);
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    switch (qobject_type(obj)) {
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    case QTYPE_QFLOAT:
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        return qfloat_get_double(qobject_to_qfloat(obj));
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    case QTYPE_QINT:
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        return qint_get_int(qobject_to_qint(obj));
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    default:
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        abort();
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    }
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}
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/**
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 * qdict_get_int(): Get an integer mapped by 'key'
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 *
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 * This function assumes that 'key' exists and it stores a
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 * QInt object.
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 *
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 * Return integer mapped by 'key'.
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 */
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int64_t qdict_get_int(const QDict *qdict, const char *key)
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{
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    QObject *obj = qdict_get_obj(qdict, key, QTYPE_QINT);
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    return qint_get_int(qobject_to_qint(obj));
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}
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/**
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 * qdict_get_bool(): Get a bool mapped by 'key'
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 *
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 * This function assumes that 'key' exists and it stores a
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 * QBool object.
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 *
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 * Return bool mapped by 'key'.
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 */
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int qdict_get_bool(const QDict *qdict, const char *key)
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{
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    QObject *obj = qdict_get_obj(qdict, key, QTYPE_QBOOL);
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    return qbool_get_int(qobject_to_qbool(obj));
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}
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/**
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 * qdict_get_qlist(): Get the QList mapped by 'key'
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 *
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 * This function assumes that 'key' exists and it stores a
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 * QList object.
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 *
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 * Return QList mapped by 'key'.
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 */
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QList *qdict_get_qlist(const QDict *qdict, const char *key)
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{
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    return qobject_to_qlist(qdict_get_obj(qdict, key, QTYPE_QLIST));
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}
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/**
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 * qdict_get_qdict(): Get the QDict mapped by 'key'
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 *
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 * This function assumes that 'key' exists and it stores a
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 * QDict object.
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 *
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 * Return QDict mapped by 'key'.
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 */
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QDict *qdict_get_qdict(const QDict *qdict, const char *key)
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{
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    return qobject_to_qdict(qdict_get_obj(qdict, key, QTYPE_QDICT));
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}
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/**
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 * qdict_get_str(): Get a pointer to the stored string mapped
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 * by 'key'
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 *
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 * This function assumes that 'key' exists and it stores a
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 * QString object.
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 *
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 * Return pointer to the string mapped by 'key'.
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 */
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const char *qdict_get_str(const QDict *qdict, const char *key)
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{
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    QObject *obj = qdict_get_obj(qdict, key, QTYPE_QSTRING);
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    return qstring_get_str(qobject_to_qstring(obj));
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}
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/**
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 * qdict_get_try_int(): Try to get integer mapped by 'key'
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 *
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 * Return integer mapped by 'key', if it is not present in
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 * the dictionary or if the stored object is not of QInt type
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 * 'def_value' will be returned.
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 */
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int64_t qdict_get_try_int(const QDict *qdict, const char *key,
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                          int64_t def_value)
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{
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    QObject *obj;
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    obj = qdict_get(qdict, key);
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    if (!obj || qobject_type(obj) != QTYPE_QINT)
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        return def_value;
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    return qint_get_int(qobject_to_qint(obj));
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}
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/**
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 * qdict_get_try_bool(): Try to get a bool mapped by 'key'
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 *
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 * Return bool mapped by 'key', if it is not present in the
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 * dictionary or if the stored object is not of QBool type
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 * 'def_value' will be returned.
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 */
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int qdict_get_try_bool(const QDict *qdict, const char *key, int def_value)
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{
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    QObject *obj;
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    obj = qdict_get(qdict, key);
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    if (!obj || qobject_type(obj) != QTYPE_QBOOL)
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        return def_value;
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    return qbool_get_int(qobject_to_qbool(obj));
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}
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/**
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 * qdict_get_try_str(): Try to get a pointer to the stored string
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 * mapped by 'key'
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 *
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 * Return a pointer to the string mapped by 'key', if it is not present
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 * in the dictionary or if the stored object is not of QString type
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 * NULL will be returned.
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 */
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const char *qdict_get_try_str(const QDict *qdict, const char *key)
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{
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    QObject *obj;
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    obj = qdict_get(qdict, key);
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    if (!obj || qobject_type(obj) != QTYPE_QSTRING)
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        return NULL;
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    return qstring_get_str(qobject_to_qstring(obj));
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}
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/**
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 * qdict_iter(): Iterate over all the dictionary's stored values.
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 *
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 * This function allows the user to provide an iterator, which will be
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 * called for each stored value in the dictionary.
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 */
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void qdict_iter(const QDict *qdict,
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                void (*iter)(const char *key, QObject *obj, void *opaque),
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                void *opaque)
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{
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    int i;
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    QDictEntry *entry;
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    for (i = 0; i < QDICT_BUCKET_MAX; i++) {
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        QLIST_FOREACH(entry, &qdict->table[i], next)
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            iter(entry->key, entry->value, opaque);
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    }
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}
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static QDictEntry *qdict_next_entry(const QDict *qdict, int first_bucket)
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{
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    int i;
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    for (i = first_bucket; i < QDICT_BUCKET_MAX; i++) {
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        if (!QLIST_EMPTY(&qdict->table[i])) {
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            return QLIST_FIRST(&qdict->table[i]);
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        }
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    }
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    return NULL;
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}
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/**
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 * qdict_first(): Return first qdict entry for iteration.
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 */
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const QDictEntry *qdict_first(const QDict *qdict)
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{
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    return qdict_next_entry(qdict, 0);
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}
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/**
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 * qdict_next(): Return next qdict entry in an iteration.
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 */
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const QDictEntry *qdict_next(const QDict *qdict, const QDictEntry *entry)
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{
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    QDictEntry *ret;
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    ret = QLIST_NEXT(entry, next);
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    if (!ret) {
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        unsigned int bucket = tdb_hash(entry->key) % QDICT_BUCKET_MAX;
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        ret = qdict_next_entry(qdict, bucket + 1);
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    }
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    return ret;
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}
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/**
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 * qentry_destroy(): Free all the memory allocated by a QDictEntry
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 */
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static void qentry_destroy(QDictEntry *e)
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{
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    assert(e != NULL);
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    assert(e->key != NULL);
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    assert(e->value != NULL);
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    qobject_decref(e->value);
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    g_free(e->key);
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    g_free(e);
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}
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/**
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 * qdict_del(): Delete a 'key:value' pair from the dictionary
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 *
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 * This will destroy all data allocated by this entry.
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 */
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void qdict_del(QDict *qdict, const char *key)
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{
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    QDictEntry *entry;
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    entry = qdict_find(qdict, key, tdb_hash(key) % QDICT_BUCKET_MAX);
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    if (entry) {
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        QLIST_REMOVE(entry, next);
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        qentry_destroy(entry);
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        qdict->size--;
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    }
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}
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/**
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 * qdict_destroy_obj(): Free all the memory allocated by a QDict
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 */
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static void qdict_destroy_obj(QObject *obj)
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{
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    int i;
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    QDict *qdict;
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    assert(obj != NULL);
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    qdict = qobject_to_qdict(obj);
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    for (i = 0; i < QDICT_BUCKET_MAX; i++) {
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        QDictEntry *entry = QLIST_FIRST(&qdict->table[i]);
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        while (entry) {
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            QDictEntry *tmp = QLIST_NEXT(entry, next);
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            QLIST_REMOVE(entry, next);
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            qentry_destroy(entry);
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            entry = tmp;
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        }
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    }
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    g_free(qdict);
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}