From 7990d2c99c974ae8e3c3f719d8321ddc6eac93bc Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Mon, 19 Jan 2015 21:22:45 +0100 Subject: qdict: Add qdict_{set,copy}_default() 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 Reviewed-by: Max Reitz Reviewed-by: Eric Blake --- include/qapi/qmp/qdict.h | 3 +++ qobject/qdict.c | 33 +++++++++++++++++++++++++++++++++ 2 files changed, 36 insertions(+) diff --git a/include/qapi/qmp/qdict.h b/include/qapi/qmp/qdict.h index d20db943fb..9fbf68ee0c 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 50c0ab378b..190791becf 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); -- cgit v1.2.1