From 096bb1ca93a22a0ca874b76c3ad03385a5667f41 Mon Sep 17 00:00:00 2001
From: Markus Armbruster <armbru@redhat.com>
Date: Mon, 18 Jun 2018 08:43:24 +0200
Subject: [PATCH 17/54] block-qdict: Clean up qdict_crumple() a bit

RH-Author: Markus Armbruster <armbru@redhat.com>
Message-id: <20180618084330.30009-18-armbru@redhat.com>
Patchwork-id: 80729
O-Subject: [RHEL-7.6 qemu-kvm-rhev PATCH 17/23] block-qdict: Clean up qdict_crumple() a bit
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>

When you mix scalar and non-scalar keys, whether you get an "already
set as scalar" or an "already set as dict" error depends on qdict
iteration order.  Neither message makes much sense.  Replace by
""Cannot mix scalar and non-scalar keys".  This is similar to the
message we get for mixing list and non-list keys.

I find qdict_crumple()'s first loop hard to understand.  Rearrange it
and add a comment.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
(cherry picked from commit 3692b5d76819e573dedc9004c4b2b0e3dad83530)
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 qobject/block-qdict.c | 32 ++++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/qobject/block-qdict.c b/qobject/block-qdict.c
index a4e1c8d..36cf58a 100644
--- a/qobject/block-qdict.c
+++ b/qobject/block-qdict.c
@@ -403,7 +403,7 @@ static int qdict_is_list(QDict *maybe_list, Error **errp)
 QObject *qdict_crumple(const QDict *src, Error **errp)
 {
     const QDictEntry *ent;
-    QDict *two_level, *multi_level = NULL;
+    QDict *two_level, *multi_level = NULL, *child_dict;
     QObject *dst = NULL, *child;
     size_t i;
     char *prefix = NULL;
@@ -422,28 +422,28 @@ QObject *qdict_crumple(const QDict *src, Error **errp)
         }
 
         qdict_split_flat_key(ent->key, &prefix, &suffix);
-
         child = qdict_get(two_level, prefix);
+        child_dict = qobject_to(QDict, child);
+
+        if (child) {
+            /*
+             * If @child_dict, then all previous keys with this prefix
+             * had a suffix.  If @suffix, this one has one as well,
+             * and we're good, else there's a clash.
+             */
+            if (!child_dict || !suffix) {
+                error_setg(errp, "Cannot mix scalar and non-scalar keys");
+                goto error;
+            }
+        }
+
         if (suffix) {
-            QDict *child_dict = qobject_to(QDict, child);
             if (!child_dict) {
-                if (child) {
-                    error_setg(errp, "Key %s prefix is already set as a scalar",
-                               prefix);
-                    goto error;
-                }
-
                 child_dict = qdict_new();
-                qdict_put_obj(two_level, prefix, QOBJECT(child_dict));
+                qdict_put(two_level, prefix, child_dict);
             }
-
             qdict_put_obj(child_dict, suffix, qobject_ref(ent->value));
         } else {
-            if (child) {
-                error_setg(errp, "Key %s prefix is already set as a dict",
-                           prefix);
-                goto error;
-            }
             qdict_put_obj(two_level, prefix, qobject_ref(ent->value));
         }
 
-- 
1.8.3.1