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>

4 files changed, 15 insertions, 43 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);
diff --git a/hw/core/machine.c b/hw/core/machine.c
index 05dcaf09c9..de3b8f1b31 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -504,11 +504,7 @@ static void machine_set_nvdimm_persistence(Object *obj, const char *value,
 
 void machine_class_allow_dynamic_sysbus_dev(MachineClass *mc, const char *type)
 {
-    strList *item = g_new0(strList, 1);
-
-    item->value = g_strdup(type);
-    item->next = mc->allowed_dynamic_sysbus_devices;
-    mc->allowed_dynamic_sysbus_devices = item;
+    QAPI_LIST_PREPEND(mc->allowed_dynamic_sysbus_devices, g_strdup(type));
 }
 
 static void validate_sysbus_device(SysBusDevice *sbdev, void *opaque)
@@ -569,7 +565,6 @@ HotpluggableCPUList *machine_query_hotpluggable_cpus(MachineState *machine)
 
     for (i = 0; i < machine->possible_cpus->len; i++) {
         Object *cpu;
-        HotpluggableCPUList *list_item = g_new0(typeof(*list_item), 1);
         HotpluggableCPU *cpu_item = g_new0(typeof(*cpu_item), 1);
 
         cpu_item->type = g_strdup(machine->possible_cpus->cpus[i].type);
@@ -582,9 +577,7 @@ HotpluggableCPUList *machine_query_hotpluggable_cpus(MachineState *machine)
             cpu_item->has_qom_path = true;
             cpu_item->qom_path = object_get_canonical_path(cpu);
         }
-        list_item->value = cpu_item;
-        list_item->next = head;
-        head = list_item;
+        QAPI_LIST_PREPEND(head, cpu_item);
     }
     return head;
 }
diff --git a/hw/net/rocker/rocker_of_dpa.c b/hw/net/rocker/rocker_of_dpa.c
index 8e347d1ee4..b3b8c5bb6d 100644
--- a/hw/net/rocker/rocker_of_dpa.c
+++ b/hw/net/rocker/rocker_of_dpa.c
@@ -2296,7 +2296,6 @@ static void of_dpa_flow_fill(void *cookie, void *value, void *user_data)
     struct of_dpa_flow_key *key = &flow->key;
     struct of_dpa_flow_key *mask = &flow->mask;
     struct of_dpa_flow_fill_context *flow_context = user_data;
-    RockerOfDpaFlowList *new;
     RockerOfDpaFlow *nflow;
     RockerOfDpaFlowKey *nkey;
     RockerOfDpaFlowMask *nmask;
@@ -2307,8 +2306,7 @@ static void of_dpa_flow_fill(void *cookie, void *value, void *user_data)
         return;
     }
 
-    new = g_malloc0(sizeof(*new));
-    nflow = new->value = g_malloc0(sizeof(*nflow));
+    nflow = g_malloc0(sizeof(*nflow));
     nkey = nflow->key = g_malloc0(sizeof(*nkey));
     nmask = nflow->mask = g_malloc0(sizeof(*nmask));
     naction = nflow->action = g_malloc0(sizeof(*naction));
@@ -2424,8 +2422,7 @@ static void of_dpa_flow_fill(void *cookie, void *value, void *user_data)
         naction->new_vlan_id = flow->action.apply.new_vlan_id;
     }
 
-    new->next = flow_context->list;
-    flow_context->list = new;
+    QAPI_LIST_PREPEND(flow_context->list, nflow);
 }
 
 RockerOfDpaFlowList *qmp_query_rocker_of_dpa_flows(const char *name,
@@ -2469,9 +2466,7 @@ static void of_dpa_group_fill(void *key, void *value, void *user_data)
 {
     struct of_dpa_group *group = value;
     struct of_dpa_group_fill_context *flow_context = user_data;
-    RockerOfDpaGroupList *new;
     RockerOfDpaGroup *ngroup;
-    struct uint32List *id;
     int i;
 
     if (flow_context->type != 9 &&
@@ -2479,8 +2474,7 @@ static void of_dpa_group_fill(void *key, void *value, void *user_data)
         return;
     }
 
-    new = g_malloc0(sizeof(*new));
-    ngroup = new->value = g_malloc0(sizeof(*ngroup));
+    ngroup = g_malloc0(sizeof(*ngroup));
 
     ngroup->id = group->id;
 
@@ -2525,10 +2519,7 @@ static void of_dpa_group_fill(void *key, void *value, void *user_data)
         ngroup->index = ROCKER_GROUP_INDEX_GET(group->id);
         for (i = 0; i < group->l2_flood.group_count; i++) {
             ngroup->has_group_ids = true;
-            id = g_malloc0(sizeof(*id));
-            id->value = group->l2_flood.group_ids[i];
-            id->next = ngroup->group_ids;
-            ngroup->group_ids = id;
+            QAPI_LIST_PREPEND(ngroup->group_ids, group->l2_flood.group_ids[i]);
         }
         break;
     case ROCKER_OF_DPA_GROUP_TYPE_L3_UCAST:
@@ -2557,8 +2548,7 @@ static void of_dpa_group_fill(void *key, void *value, void *user_data)
         break;
     }
 
-    new->next = flow_context->list;
-    flow_context->list = new;
+    QAPI_LIST_PREPEND(flow_context->list, ngroup);
 }
 
 RockerOfDpaGroupList *qmp_query_rocker_of_dpa_groups(const char *name,
diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index 044ac95f6f..8356eeec13 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -437,17 +437,14 @@ static void rxfilter_notify(NetClientState *nc)
 
 static intList *get_vlan_table(VirtIONet *n)
 {
-    intList *list, *entry;
+    intList *list;
     int i, j;
 
     list = NULL;
     for (i = 0; i < MAX_VLAN >> 5; i++) {
         for (j = 0; n->vlans[i] && j <= 0x1f; j++) {
             if (n->vlans[i] & (1U << j)) {
-                entry = g_malloc0(sizeof(*entry));
-                entry->value = (i << 5) + j;
-                entry->next = list;
-                list = entry;
+                QAPI_LIST_PREPEND(list, (i << 5) + j);
             }
         }
     }
@@ -460,7 +457,7 @@ static RxFilterInfo *virtio_net_query_rxfilter(NetClientState *nc)
     VirtIONet *n = qemu_get_nic_opaque(nc);
     VirtIODevice *vdev = VIRTIO_DEVICE(n);
     RxFilterInfo *info;
-    strList *str_list, *entry;
+    strList *str_list;
     int i;
 
     info = g_malloc0(sizeof(*info));
@@ -491,19 +488,15 @@ static RxFilterInfo *virtio_net_query_rxfilter(NetClientState *nc)
 
     str_list = NULL;
     for (i = 0; i < n->mac_table.first_multi; i++) {
-        entry = g_malloc0(sizeof(*entry));
-        entry->value = qemu_mac_strdup_printf(n->mac_table.macs + i * ETH_ALEN);
-        entry->next = str_list;
-        str_list = entry;
+        QAPI_LIST_PREPEND(str_list,
+                      qemu_mac_strdup_printf(n->mac_table.macs + i * ETH_ALEN));
     }
     info->unicast_table = str_list;
 
     str_list = NULL;
     for (i = n->mac_table.first_multi; i < n->mac_table.in_use; i++) {
-        entry = g_malloc0(sizeof(*entry));
-        entry->value = qemu_mac_strdup_printf(n->mac_table.macs + i * ETH_ALEN);
-        entry->next = str_list;
-        str_list = entry;
+        QAPI_LIST_PREPEND(str_list,
+                      qemu_mac_strdup_printf(n->mac_table.macs + i * ETH_ALEN));
     }
     info->multicast_table = str_list;
     info->vlan_table = get_vlan_table(n);