From c2eb29efe61ffe88d3aff449446a9ac0f0f045a5 Mon Sep 17 00:00:00 2001 From: Richard Jones Date: Tue, 2 Jun 2015 09:46:37 +0200 Subject: [PATCH 3/4] block: Allow JSON filenames Message-id: <1433238397-2500-3-git-send-email-rjones@redhat.com> Patchwork-id: 65279 O-Subject: [RHEL-7.2 qemu-kvm PATCH 2/2] block: Allow JSON filenames Bugzilla: 1226697 RH-Acked-by: Miroslav Rezanina RH-Acked-by: Stefan Hajnoczi RH-Acked-by: Max Reitz From: Max Reitz If the filename given to bdrv_open() is prefixed with "json:", parse the rest as a JSON object and merge the result into the options QDict. If there are conflicts, the options QDict takes precedence. Signed-off-by: Max Reitz Reviewed-by: Eric Blake Signed-off-by: Kevin Wolf Signed-off-by: Miroslav Rezanina --- block.c | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) diff --git a/block.c b/block.c index 45543d5..f2caf20 100644 --- a/block.c +++ b/block.c @@ -1085,6 +1085,33 @@ static void extract_subqdict(QDict *src, QDict **dst, const char *start) } } +static QDict *parse_json_filename(const char *filename, Error **errp) +{ + QObject *options_obj; + QDict *options; + int ret; + + ret = strstart(filename, "json:", &filename); + assert(ret); + + options_obj = qobject_from_json(filename); + if (!options_obj) { + error_setg(errp, "Could not parse the JSON options"); + return NULL; + } + + if (qobject_type(options_obj) != QTYPE_QDICT) { + qobject_decref(options_obj); + error_setg(errp, "Invalid JSON object given"); + return NULL; + } + + options = qobject_to_qdict(options_obj); + qdict_flatten(options); + + return options; +} + /* * Opens a disk image (raw, qcow2, vmdk, ...) * @@ -1109,6 +1136,20 @@ int bdrv_open(BlockDriverState *bs, const char *filename, QDict *options, options = qdict_new(); } + if (filename && g_str_has_prefix(filename, "json:")) { + QDict *json_options = parse_json_filename(filename, &local_err); + if (local_err) { + ret = -EINVAL; + goto fail; + } + + /* Options given in the filename have lower priority than options + * specified directly */ + qdict_join(options, json_options, false); + QDECREF(json_options); + filename = NULL; + } + bs->options = options; options = qdict_clone_shallow(options); -- 1.8.3.1