qobject/qlist.c

   1 /*
   2  * QList 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 "qapi/qmp/qlist.h"
  14 #include "qapi/qmp/qobject.h"
  15 #include "qemu/queue.h"
  16 #include "qemu-common.h"
  17
  18 /**
  19  * qlist_new(): Create a new QList
  20  *
  21  * Return strong reference.
  22  */
  23 QList *qlist_new(void)
  24 {
  25     QList *qlist;
  26
  27     qlist = g_malloc(sizeof(*qlist));
  28     qobject_init(QOBJECT(qlist), QTYPE_QLIST);
  29     QTAILQ_INIT(&qlist->head);
  30
  31     return qlist;
  32 }
  33
  34 static void qlist_copy_elem(QObject *obj, void *opaque)
  35 {
  36     QList *dst = opaque;
  37
  38     qobject_incref(obj);
  39     qlist_append_obj(dst, obj);
  40 }
  41
  42 QList *qlist_copy(QList *src)
  43 {
  44     QList *dst = qlist_new();
  45
  46     qlist_iter(src, qlist_copy_elem, dst);
  47
  48     return dst;
  49 }
  50
  51 /**
  52  * qlist_append_obj(): Append an QObject into QList
  53  *
  54  * NOTE: ownership of 'value' is transferred to the QList
  55  */
  56 void qlist_append_obj(QList *qlist, QObject *value)
  57 {
  58     QListEntry *entry;
  59
  60     entry = g_malloc(sizeof(*entry));
  61     entry->value = value;
  62
  63     QTAILQ_INSERT_TAIL(&qlist->head, entry, next);
  64 }
  65
  66 /**
  67  * qlist_iter(): Iterate over all the list's stored values.
  68  *
  69  * This function allows the user to provide an iterator, which will be
  70  * called for each stored value in the list.
  71  */
  72 void qlist_iter(const QList *qlist,
  73                 void (*iter)(QObject *obj, void *opaque), void *opaque)
  74 {
  75     QListEntry *entry;
  76
  77     QTAILQ_FOREACH(entry, &qlist->head, next)
  78         iter(entry->value, opaque);
  79 }
  80
  81 QObject *qlist_pop(QList *qlist)
  82 {
  83     QListEntry *entry;
  84     QObject *ret;
  85
  86     if (qlist == NULL || QTAILQ_EMPTY(&qlist->head)) {
  87         return NULL;
  88     }
  89
  90     entry = QTAILQ_FIRST(&qlist->head);
  91     QTAILQ_REMOVE(&qlist->head, entry, next);
  92
  93     ret = entry->value;
  94     g_free(entry);
  95
  96     return ret;
  97 }
  98
  99 QObject *qlist_peek(QList *qlist)
 100 {
 101     QListEntry *entry;
 102     QObject *ret;
 103
 104     if (qlist == NULL || QTAILQ_EMPTY(&qlist->head)) {
 105         return NULL;
 106     }
 107
 108     entry = QTAILQ_FIRST(&qlist->head);
 109
 110     ret = entry->value;
 111
 112     return ret;
 113 }
 114
 115 int qlist_empty(const QList *qlist)
 116 {
 117     return QTAILQ_EMPTY(&qlist->head);
 118 }
 119
 120 static void qlist_size_iter(QObject *obj, void *opaque)
 121 {
 122     size_t *count = opaque;
 123     (*count)++;
 124 }
 125
 126 size_t qlist_size(const QList *qlist)
 127 {
 128     size_t count = 0;
 129     qlist_iter(qlist, qlist_size_iter, &count);
 130     return count;
 131 }
 132
 133 /**
 134  * qobject_to_qlist(): Convert a QObject into a QList
 135  */
 136 QList *qobject_to_qlist(const QObject *obj)
 137 {
 138     if (!obj || qobject_type(obj) != QTYPE_QLIST) {
 139         return NULL;
 140     }
 141     return container_of(obj, QList, base);
 142 }
 143
 144 /**
 145  * qlist_destroy_obj(): Free all the memory allocated by a QList
 146  */
 147 void qlist_destroy_obj(QObject *obj)
 148 {
 149     QList *qlist;
 150     QListEntry *entry, *next_entry;
 151
 152     assert(obj != NULL);
 153     qlist = qobject_to_qlist(obj);
 154
 155     QTAILQ_FOREACH_SAFE(entry, &qlist->head, next, next_entry) {
 156         QTAILQ_REMOVE(&qlist->head, entry, next);
 157         qobject_decref(entry->value);
 158         g_free(entry);
 159     }
 160
 161     g_free(qlist);
 162 }