From dd98e8481992741a6b5ec0bdfcee05c1c8f602d6 Mon Sep 17 00:00:00 2001 From: Markus Armbruster Date: Thu, 23 Aug 2018 18:40:14 +0200 Subject: [PATCH] qjson: Have qobject_from_json() & friends reject empty and blank The last case where qobject_from_json() & friends return null without setting an error is empty or blank input. Callers: * block.c's parse_json_protocol() reports "Could not parse the JSON options". It's marked as a work-around, because it also covered actual bugs, but they got fixed in the previous few commits. * qobject_input_visitor_new_str() reports "JSON parse error". Also marked as work-around. The recent fixes have made this unreachable, because it currently gets called only for input starting with '{'. * check-qjson.c's empty_input() and blank_input() demonstrate the behavior. * The other callers are not affected since they only pass input with exactly one JSON value or, in the case of negative tests, one error. Fail with "Expecting a JSON value" instead of returning null, and simplify callers. Signed-off-by: Markus Armbruster Reviewed-by: Eric Blake Message-Id: <20180823164025.12553-48-armbru@redhat.com> --- block.c | 5 ----- qapi/qobject-input-visitor.c | 5 ----- qobject/qjson.c | 4 ++++ tests/check-qjson.c | 12 ++++++++++-- 4 files changed, 14 insertions(+), 12 deletions(-) diff --git a/block.c b/block.c index 6161dbe3eb..0dbb1fcc7b 100644 --- a/block.c +++ b/block.c @@ -1478,11 +1478,6 @@ static QDict *parse_json_filename(const char *filename, Error **errp) options_obj = qobject_from_json(filename, errp); if (!options_obj) { - /* Work around qobject_from_json() lossage TODO fix that */ - if (errp && !*errp) { - error_setg(errp, "Could not parse the JSON options"); - return NULL; - } error_prepend(errp, "Could not parse the JSON options: "); return NULL; } diff --git a/qapi/qobject-input-visitor.c b/qapi/qobject-input-visitor.c index da57f4cc24..3e88b27f9e 100644 --- a/qapi/qobject-input-visitor.c +++ b/qapi/qobject-input-visitor.c @@ -725,11 +725,6 @@ Visitor *qobject_input_visitor_new_str(const char *str, if (is_json) { obj = qobject_from_json(str, errp); if (!obj) { - /* Work around qobject_from_json() lossage TODO fix that */ - if (errp && !*errp) { - error_setg(errp, "JSON parse error"); - return NULL; - } return NULL; } args = qobject_to(QDict, obj); diff --git a/qobject/qjson.c b/qobject/qjson.c index 7f69036487..b9ccae2c2a 100644 --- a/qobject/qjson.c +++ b/qobject/qjson.c @@ -70,6 +70,10 @@ static QObject *qobject_from_jsonv(const char *string, va_list *ap, json_message_parser_flush(&state.parser); json_message_parser_destroy(&state.parser); + if (!state.result && !state.err) { + error_setg(&state.err, "Expecting a JSON value"); + } + error_propagate(errp, state.err); return state.result; } diff --git a/tests/check-qjson.c b/tests/check-qjson.c index 0ca4b3c823..936258ddd4 100644 --- a/tests/check-qjson.c +++ b/tests/check-qjson.c @@ -1291,13 +1291,21 @@ static void simple_interpolation(void) static void empty_input(void) { - QObject *obj = qobject_from_json("", &error_abort); + Error *err = NULL; + QObject *obj; + + obj = qobject_from_json("", &err); + error_free_or_abort(&err); g_assert(obj == NULL); } static void blank_input(void) { - QObject *obj = qobject_from_json("\n ", &error_abort); + Error *err = NULL; + QObject *obj; + + obj = qobject_from_json("\n ", &err); + error_free_or_abort(&err); g_assert(obj == NULL); }