diff mbox

[v2,02/13] qdict: Add qdict_{set, copy}_default()

Message ID 1433944027-28533-3-git-send-email-kwolf@redhat.com
State New
Headers show

Commit Message

Kevin Wolf June 10, 2015, 1:46 p.m. UTC 
In the block layer functions that determine options for a child block
device, it's a common pattern to either copy options from the parent's
options or to set a default string if the option isn't explicitly set
yet for the child. Provide convenience functions so that it becomes a
one-liner for each option.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 include/qapi/qmp/qdict.h |  3 +++
 qobject/qdict.c          | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 36 insertions(+)

Comments

Eric Blake June 10, 2015, 9:29 p.m. UTC | #1 
On 06/10/2015 07:46 AM, Kevin Wolf wrote:
> In the block layer functions that determine options for a child block
> device, it's a common pattern to either copy options from the parent's
> options or to set a default string if the option isn't explicitly set
> yet for the child. Provide convenience functions so that it becomes a
> one-liner for each option.
> 
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> Reviewed-by: Max Reitz <mreitz@redhat.com>
> ---
>  include/qapi/qmp/qdict.h |  3 +++
>  qobject/qdict.c          | 33 +++++++++++++++++++++++++++++++++
>  2 files changed, 36 insertions(+)
> 

Reviewed-by: Eric Blake <eblake@redhat.com>
diff mbox

Patch

diff --git a/include/qapi/qmp/qdict.h b/include/qapi/qmp/qdict.h
index d20db94..9fbf68e 100644
--- a/include/qapi/qmp/qdict.h
+++ b/include/qapi/qmp/qdict.h
@@ -65,6 +65,9 @@  int64_t qdict_get_try_int(const QDict *qdict, const char *key,
 int qdict_get_try_bool(const QDict *qdict, const char *key, int def_value);
 const char *qdict_get_try_str(const QDict *qdict, const char *key);
 
+void qdict_copy_default(QDict *dst, QDict *src, const char *key);
+void qdict_set_default_str(QDict *dst, const char *key, const char *val);
+
 QDict *qdict_clone_shallow(const QDict *src);
 void qdict_flatten(QDict *qdict);
 
diff --git a/qobject/qdict.c b/qobject/qdict.c
index 50c0ab3..190791b 100644
--- a/qobject/qdict.c
+++ b/qobject/qdict.c
@@ -477,6 +477,39 @@  static void qdict_destroy_obj(QObject *obj)
     g_free(qdict);
 }
 
+/**
+ * qdict_copy_default(): If no entry mapped by 'key' exists in 'dst' yet, the
+ * value of 'key' in 'src' is copied there (and the refcount increased
+ * accordingly).
+ */
+void qdict_copy_default(QDict *dst, QDict *src, const char *key)
+{
+    QObject *val;
+
+    if (qdict_haskey(dst, key)) {
+        return;
+    }
+
+    val = qdict_get(src, key);
+    if (val) {
+        qobject_incref(val);
+        qdict_put_obj(dst, key, val);
+    }
+}
+
+/**
+ * qdict_set_default_str(): If no entry mapped by 'key' exists in 'dst' yet, a
+ * new QString initialised by 'val' is put there.
+ */
+void qdict_set_default_str(QDict *dst, const char *key, const char *val)
+{
+    if (qdict_haskey(dst, key)) {
+        return;
+    }
+
+    qdict_put(dst, key, qstring_from_str(val));
+}
+
 static void qdict_flatten_qdict(QDict *qdict, QDict *target,
                                 const char *prefix);