qapi: Use QAPI_LIST_PREPEND() where possible

Anywhere we create a list of just one item or by prepending items
(typically because order doesn't matter), we can use
QAPI_LIST_PREPEND().  But places where we must keep the list in order
by appending remain open-coded until later patches.

Note that as a side effect, this also performs a cleanup of two minor
issues in qga/commands-posix.c: the old code was performing
 new = g_malloc0(sizeof(*ret));
which 1) is confusing because you have to verify whether 'new' and
'ret' are variables with the same type, and 2) would conflict with C++
compilation (not an actual problem for this file, but makes
copy-and-paste harder).

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20201113011340.463563-5-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
[Straightforward conflicts due to commit a8aa94b5f8 "qga: update
schema for guest-get-disks 'dependents' field" and commit a10b453a52
"target/mips: Move mips_cpu_add_definition() from helper.c to cpu.c"
resolved.  Commit message tweaked.]
Signed-off-by: Markus Armbruster <armbru@redhat.com>

2 files changed, 13 insertions, 24 deletions

diff --git a/ui/input.c b/ui/input.c
index 4791b089c7..8ac407dec4 100644
--- a/ui/input.c
+++ b/ui/input.c
@@ -571,7 +571,7 @@ void qemu_remove_mouse_mode_change_notifier(Notifier *notify)
 MouseInfoList *qmp_query_mice(Error **errp)
 {
     MouseInfoList *mice_list = NULL;
-    MouseInfoList *info;
+    MouseInfo *info;
     QemuInputHandlerState *s;
     bool current = true;
 
@@ -581,16 +581,14 @@ MouseInfoList *qmp_query_mice(Error **errp)
             continue;
         }
 
-        info = g_new0(MouseInfoList, 1);
-        info->value = g_new0(MouseInfo, 1);
-        info->value->index = s->id;
-        info->value->name = g_strdup(s->handler->name);
-        info->value->absolute = s->handler->mask & INPUT_EVENT_MASK_ABS;
-        info->value->current = current;
+        info = g_new0(MouseInfo, 1);
+        info->index = s->id;
+        info->name = g_strdup(s->handler->name);
+        info->absolute = s->handler->mask & INPUT_EVENT_MASK_ABS;
+        info->current = current;
 
         current = false;
-        info->next = mice_list;
-        mice_list = info;
+        QAPI_LIST_PREPEND(mice_list, info);
     }
 
     return mice_list;
diff --git a/ui/vnc.c b/ui/vnc.c
index 34e6dc437c..7452ac7df2 100644
--- a/ui/vnc.c
+++ b/ui/vnc.c
@@ -365,14 +365,11 @@ static VncDisplay *vnc_display_find(const char *id)
 
 static VncClientInfoList *qmp_query_client_list(VncDisplay *vd)
 {
-    VncClientInfoList *cinfo, *prev = NULL;
+    VncClientInfoList *prev = NULL;
     VncState *client;
 
     QTAILQ_FOREACH(client, &vd->clients, next) {
-        cinfo = g_new0(VncClientInfoList, 1);
-        cinfo->value = qmp_query_vnc_client(client);
-        cinfo->next = prev;
-        prev = cinfo;
+        QAPI_LIST_PREPEND(prev, qmp_query_vnc_client(client));
     }
     return prev;
 }
@@ -453,7 +450,6 @@ static VncServerInfo2List *qmp_query_server_entry(QIOChannelSocket *ioc,
                                                   int subauth,
                                                   VncServerInfo2List *prev)
 {
-    VncServerInfo2List *list;
     VncServerInfo2 *info;
     Error *err = NULL;
     SocketAddress *addr;
@@ -476,10 +472,8 @@ static VncServerInfo2List *qmp_query_server_entry(QIOChannelSocket *ioc,
     qmp_query_auth(auth, subauth, &info->auth,
                    &info->vencrypt, &info->has_vencrypt);
 
-    list = g_new0(VncServerInfo2List, 1);
-    list->value = info;
-    list->next = prev;
-    return list;
+    QAPI_LIST_PREPEND(prev, info);
+    return prev;
 }
 
 static void qmp_query_auth(int auth, int subauth,
@@ -554,7 +548,7 @@ static void qmp_query_auth(int auth, int subauth,
 
 VncInfo2List *qmp_query_vnc_servers(Error **errp)
 {
-    VncInfo2List *item, *prev = NULL;
+    VncInfo2List *prev = NULL;
     VncInfo2 *info;
     VncDisplay *vd;
     DeviceState *dev;
@@ -583,10 +577,7 @@ VncInfo2List *qmp_query_vnc_servers(Error **errp)
                 vd->ws_subauth, info->server);
         }
 
-        item = g_new0(VncInfo2List, 1);
-        item->value = info;
-        item->next = prev;
-        prev = item;
+        QAPI_LIST_PREPEND(prev, info);
     }
     return prev;
 }