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>

1 files changed, 1 insertions, 5 deletions

diff --git a/hw/core/machine-qmp-cmds.c b/hw/core/machine-qmp-cmds.c
index 87f14140a3..affffe0c4a 100644
--- a/hw/core/machine-qmp-cmds.c
+++ b/hw/core/machine-qmp-cmds.c
@@ -215,7 +215,6 @@ MachineInfoList *qmp_query_machines(Error **errp)
 
     for (el = machines; el; el = el->next) {
         MachineClass *mc = el->data;
-        MachineInfoList *entry;
         MachineInfo *info;
 
         info = g_malloc0(sizeof(*info));
@@ -243,10 +242,7 @@ MachineInfoList *qmp_query_machines(Error **errp)
             info->has_default_ram_id = true;
         }
 
-        entry = g_malloc0(sizeof(*entry));
-        entry->value = info;
-        entry->next = mach_list;
-        mach_list = entry;
+        QAPI_LIST_PREPEND(mach_list, info);
     }
 
     g_slist_free(machines);