From 91f887335e57e6cdd891d7341ac070ca9359ac82 Mon Sep 17 00:00:00 2001
From: Markus Armbruster <armbru@redhat.com>
Date: Mon, 18 Jun 2018 08:43:28 +0200
Subject: [PATCH 21/54] block: Fix -blockdev / blockdev-add for empty objects
and arrays
RH-Author: Markus Armbruster <armbru@redhat.com>
Message-id: <20180618084330.30009-22-armbru@redhat.com>
Patchwork-id: 80726
O-Subject: [RHEL-7.6 qemu-kvm-rhev PATCH 21/23] block: Fix -blockdev / blockdev-add for empty objects and arrays
Bugzilla: 1557995
RH-Acked-by: Max Reitz <mreitz@redhat.com>
RH-Acked-by: Jeffrey Cody <jcody@redhat.com>
RH-Acked-by: Kevin Wolf <kwolf@redhat.com>
-blockdev and blockdev-add silently ignore empty objects and arrays in
their argument. That's because qmp_blockdev_add() converts the
argument to a flat QDict, and qdict_flatten() eats empty QDict and
QList members. For instance, we ignore an empty BlockdevOptions
member @cache. No real harm, as absent means the same as empty there.
Thus, the flaw puts an artificial restriction on the QAPI schema: we
can't have potentially empty objects and arrays within
BlockdevOptions, except when they're optional and "empty" has the same
meaning as "absent".
Our QAPI schema satisfies this restriction (I checked), but it's a
trap for the unwary, and a temptation to employ awkward workarounds
for the wary. Let's get rid of it.
Change qdict_flatten() and qdict_crumple() to treat empty dictionaries
and lists exactly like scalars.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
(cherry picked from commit 2860b2b2cb883969c8f6464bd9f8bc88742c5c73)
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
qobject/block-qdict.c | 54 +++++++++++++++++++++++++++++------------------
tests/check-block-qdict.c | 38 ++++++++++++++++++++++++++-------
2 files changed, 63 insertions(+), 29 deletions(-)
diff --git a/qobject/block-qdict.c b/qobject/block-qdict.c
index e51a3d2..df83308 100644
--- a/qobject/block-qdict.c
+++ b/qobject/block-qdict.c
@@ -56,6 +56,8 @@ static void qdict_flatten_qlist(QList *qlist, QDict *target, const char *prefix)
{
QObject *value;
const QListEntry *entry;
+ QDict *dict_val;
+ QList *list_val;
char *new_key;
int i;
@@ -69,16 +71,18 @@ static void qdict_flatten_qlist(QList *qlist, QDict *target, const char *prefix)
for (i = 0; entry; entry = qlist_next(entry), i++) {
value = qlist_entry_obj(entry);
+ dict_val = qobject_to(QDict, value);
+ list_val = qobject_to(QList, value);
new_key = g_strdup_printf("%s.%i", prefix, i);
/*
* Flatten non-empty QDict and QList recursively into @target,
* copy other objects to @target
*/
- if (qobject_type(value) == QTYPE_QDICT) {
- qdict_flatten_qdict(qobject_to(QDict, value), target, new_key);
- } else if (qobject_type(value) == QTYPE_QLIST) {
- qdict_flatten_qlist(qobject_to(QList, value), target, new_key);
+ if (dict_val && qdict_size(dict_val)) {
+ qdict_flatten_qdict(dict_val, target, new_key);
+ } else if (list_val && !qlist_empty(list_val)) {
+ qdict_flatten_qlist(list_val, target, new_key);
} else {
qdict_put_obj(target, new_key, qobject_ref(value));
}
@@ -91,6 +95,8 @@ static void qdict_flatten_qdict(QDict *qdict, QDict *target, const char *prefix)
{
QObject *value;
const QDictEntry *entry, *next;
+ QDict *dict_val;
+ QList *list_val;
char *new_key;
entry = qdict_first(qdict);
@@ -98,6 +104,8 @@ static void qdict_flatten_qdict(QDict *qdict, QDict *target, const char *prefix)
while (entry != NULL) {
next = qdict_next(qdict, entry);
value = qdict_entry_value(entry);
+ dict_val = qobject_to(QDict, value);
+ list_val = qobject_to(QList, value);
new_key = NULL;
if (prefix) {
@@ -108,12 +116,12 @@ static void qdict_flatten_qdict(QDict *qdict, QDict *target, const char *prefix)
* Flatten non-empty QDict and QList recursively into @target,
* copy other objects to @target
*/
- if (qobject_type(value) == QTYPE_QDICT) {
- qdict_flatten_qdict(qobject_to(QDict, value), target,
+ if (dict_val && qdict_size(dict_val)) {
+ qdict_flatten_qdict(dict_val, target,
new_key ? new_key : entry->key);
qdict_del(qdict, entry->key);
- } else if (qobject_type(value) == QTYPE_QLIST) {
- qdict_flatten_qlist(qobject_to(QList, value), target,
+ } else if (list_val && !qlist_empty(list_val)) {
+ qdict_flatten_qlist(list_val, target,
new_key ? new_key : entry->key);
qdict_del(qdict, entry->key);
} else if (target != qdict) {
@@ -127,10 +135,11 @@ static void qdict_flatten_qdict(QDict *qdict, QDict *target, const char *prefix)
}
/**
- * qdict_flatten(): For each nested QDict with key x, all fields with key y
- * are moved to this QDict and their key is renamed to "x.y". For each nested
- * QList with key x, the field at index y is moved to this QDict with the key
- * "x.y" (i.e., the reverse of what qdict_array_split() does).
+ * qdict_flatten(): For each nested non-empty QDict with key x, all
+ * fields with key y are moved to this QDict and their key is renamed
+ * to "x.y". For each nested non-empty QList with key x, the field at
+ * index y is moved to this QDict with the key "x.y" (i.e., the
+ * reverse of what qdict_array_split() does).
* This operation is applied recursively for nested QDicts and QLists.
*/
void qdict_flatten(QDict *qdict)
@@ -361,8 +370,8 @@ static int qdict_is_list(QDict *maybe_list, Error **errp)
* @src: the original flat dictionary (only scalar values) to crumple
*
* Takes a flat dictionary whose keys use '.' separator to indicate
- * nesting, and values are scalars, and crumples it into a nested
- * structure.
+ * nesting, and values are scalars, empty dictionaries or empty lists,
+ * and crumples it into a nested structure.
*
* To include a literal '.' in a key name, it must be escaped as '..'
*
@@ -399,6 +408,8 @@ QObject *qdict_crumple(const QDict *src, Error **errp)
{
const QDictEntry *ent;
QDict *two_level, *multi_level = NULL, *child_dict;
+ QDict *dict_val;
+ QList *list_val;
QObject *dst = NULL, *child;
size_t i;
char *prefix = NULL;
@@ -409,10 +420,11 @@ QObject *qdict_crumple(const QDict *src, Error **errp)
/* Step 1: split our totally flat dict into a two level dict */
for (ent = qdict_first(src); ent != NULL; ent = qdict_next(src, ent)) {
- if (qobject_type(ent->value) == QTYPE_QDICT ||
- qobject_type(ent->value) == QTYPE_QLIST) {
- error_setg(errp, "Value %s is not a scalar",
- ent->key);
+ dict_val = qobject_to(QDict, ent->value);
+ list_val = qobject_to(QList, ent->value);
+ if ((dict_val && qdict_size(dict_val))
+ || (list_val && !qlist_empty(list_val))) {
+ error_setg(errp, "Value %s is not flat", ent->key);
goto error;
}
@@ -451,9 +463,9 @@ QObject *qdict_crumple(const QDict *src, Error **errp)
multi_level = qdict_new();
for (ent = qdict_first(two_level); ent != NULL;
ent = qdict_next(two_level, ent)) {
- QDict *dict = qobject_to(QDict, ent->value);
- if (dict) {
- child = qdict_crumple(dict, errp);
+ dict_val = qobject_to(QDict, ent->value);
+ if (dict_val && qdict_size(dict_val)) {
+ child = qdict_crumple(dict_val, errp);
if (!child) {
goto error;
}
diff --git a/tests/check-block-qdict.c b/tests/check-block-qdict.c
index 2da16f0..1d20fcc 100644
--- a/tests/check-block-qdict.c
+++ b/tests/check-block-qdict.c
@@ -79,10 +79,10 @@ static void qdict_flatten_test(void)
* "e.1.2.b": 1,
* "f.c": 2,
* "f.d": 3,
- * "g": 4
+ * "g": 4,
+ * "y.0": {},
+ * "z.a": []
* }
- *
- * Note that "y" and "z" get eaten.
*/
qdict_put_int(e_1_2, "a", 0);
@@ -117,8 +117,10 @@ static void qdict_flatten_test(void)
g_assert(qdict_get_int(root, "f.c") == 2);
g_assert(qdict_get_int(root, "f.d") == 3);
g_assert(qdict_get_int(root, "g") == 4);
+ g_assert(!qdict_size(qdict_get_qdict(root, "y.0")));
+ g_assert(qlist_empty(qdict_get_qlist(root, "z.a")));
- g_assert(qdict_size(root) == 8);
+ g_assert(qdict_size(root) == 10);
qobject_unref(root);
}
@@ -387,7 +389,8 @@ static void qdict_join_test(void)
static void qdict_crumple_test_recursive(void)
{
QDict *src, *dst, *rule, *vnc, *acl, *listen;
- QList *rules;
+ QDict *empty, *empty_dict, *empty_list_0;
+ QList *rules, *empty_list, *empty_dict_a;
src = qdict_new();
qdict_put_str(src, "vnc.listen.addr", "127.0.0.1");
@@ -399,10 +402,12 @@ static void qdict_crumple_test_recursive(void)
qdict_put_str(src, "vnc.acl.default", "deny");
qdict_put_str(src, "vnc.acl..name", "acl0");
qdict_put_str(src, "vnc.acl.rule..name", "acl0");
+ qdict_put(src, "empty.dict.a", qlist_new());
+ qdict_put(src, "empty.list.0", qdict_new());
dst = qobject_to(QDict, qdict_crumple(src, &error_abort));
g_assert(dst);
- g_assert_cmpint(qdict_size(dst), ==, 1);
+ g_assert_cmpint(qdict_size(dst), ==, 2);
vnc = qdict_get_qdict(dst, "vnc");
g_assert(vnc);
@@ -440,6 +445,21 @@ static void qdict_crumple_test_recursive(void)
g_assert_cmpstr("acl0", ==, qdict_get_str(vnc, "acl.name"));
g_assert_cmpstr("acl0", ==, qdict_get_str(acl, "rule.name"));
+ empty = qdict_get_qdict(dst, "empty");
+ g_assert(empty);
+ g_assert_cmpint(qdict_size(empty), ==, 2);
+ empty_dict = qdict_get_qdict(empty, "dict");
+ g_assert(empty_dict);
+ g_assert_cmpint(qdict_size(empty_dict), ==, 1);
+ empty_dict_a = qdict_get_qlist(empty_dict, "a");
+ g_assert(empty_dict_a && qlist_empty(empty_dict_a));
+ empty_list = qdict_get_qlist(empty, "list");
+ g_assert(empty_list);
+ g_assert_cmpint(qlist_size(empty_list), ==, 1);
+ empty_list_0 = qobject_to(QDict, qlist_pop(empty_list));
+ g_assert(empty_list_0);
+ g_assert_cmpint(qdict_size(empty_list_0), ==, 0);
+
qobject_unref(src);
qobject_unref(dst);
}
@@ -587,7 +607,7 @@ static void qdict_rename_keys_test(void)
static void qdict_crumple_test_bad_inputs(void)
{
- QDict *src;
+ QDict *src, *nested;
Error *error = NULL;
src = qdict_new();
@@ -614,7 +634,9 @@ static void qdict_crumple_test_bad_inputs(void)
src = qdict_new();
/* The input should be flat, ie no dicts or lists */
- qdict_put(src, "rule.a", qdict_new());
+ nested = qdict_new();
+ qdict_put(nested, "x", qdict_new());
+ qdict_put(src, "rule.a", nested);
qdict_put_str(src, "rule.b", "allow");
g_assert(qdict_crumple(src, &error) == NULL);
--
1.8.3.1