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/*
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* QDict data type.
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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 GPL, version 2. See
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* the COPYING file in the top-level directory.
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*/
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#include "qint.h" |
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#include "qdict.h" |
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#include "qstring.h" |
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#include "qobject.h" |
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#include "sys-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 = qemu_mallocz(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 = qemu_mallocz(sizeof(*entry));
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entry->key = qemu_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_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 hash) |
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{ |
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QDictEntry *entry; |
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LIST_FOREACH(entry, &qdict->table[hash], 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 hash; |
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QDictEntry *entry; |
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hash = tdb_hash(key) % QDICT_HASH_SIZE; |
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entry = qdict_find(qdict, key, hash); |
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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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LIST_INSERT_HEAD(&qdict->table[hash], entry, next); |
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} |
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qdict->size++; |
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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_HASH_SIZE); |
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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 hash = tdb_hash(key) % QDICT_HASH_SIZE; |
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return (qdict_find(qdict, key, hash) == 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_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_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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* 'err_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 err_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 err_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_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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* 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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qemu_free(e->key); |
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qemu_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_HASH_SIZE); |
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if (entry) {
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LIST_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_HASH_SIZE; i++) { |
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QDictEntry *entry = LIST_FIRST(&qdict->table[i]); |
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while (entry) {
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QDictEntry *tmp = LIST_NEXT(entry, next); |
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LIST_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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qemu_free(qdict); |
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} |