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, 21 insertions, 71 deletions

diff --git a/qga/commands-posix-ssh.c b/qga/commands-posix-ssh.c
index 749167e82d..2dda136d64 100644
--- a/qga/commands-posix-ssh.c
+++ b/qga/commands-posix-ssh.c
@@ -293,17 +293,12 @@ qmp_guest_ssh_get_authorized_keys(const char *username, Error **errp)
 
     ret = g_new0(GuestAuthorizedKeys, 1);
     for (i = 0; authkeys[i] != NULL; i++) {
-        strList *new;
-
         g_strstrip(authkeys[i]);
         if (!authkeys[i][0] || authkeys[i][0] == '#') {
             continue;
         }
 
-        new = g_new0(strList, 1);
-        new->value = g_strdup(authkeys[i]);
-        new->next = ret->keys;
-        ret->keys = new;
+        QAPI_LIST_PREPEND(ret->keys, g_strdup(authkeys[i]));
     }
 
     return g_steal_pointer(&ret);
diff --git a/qga/commands-posix.c b/qga/commands-posix.c
index c089e38120..849923b260 100644
--- a/qga/commands-posix.c
+++ b/qga/commands-posix.c
@@ -1036,7 +1036,6 @@ static void build_guest_fsinfo_for_real_device(char const *syspath,
 {
     GuestDiskAddress *disk;
     GuestPCIAddress *pciaddr;
-    GuestDiskAddressList *list = NULL;
     bool has_hwinf;
 #ifdef CONFIG_LIBUDEV
     struct udev *udev = NULL;
@@ -1053,9 +1052,6 @@ static void build_guest_fsinfo_for_real_device(char const *syspath,
     disk->pci_controller = pciaddr;
     disk->bus_type = GUEST_DISK_BUS_TYPE_UNKNOWN;
 
-    list = g_new0(GuestDiskAddressList, 1);
-    list->value = disk;
-
 #ifdef CONFIG_LIBUDEV
     udev = udev_new();
     udevice = udev_device_new_from_syspath(udev, syspath);
@@ -1089,10 +1085,9 @@ static void build_guest_fsinfo_for_real_device(char const *syspath,
     }
 
     if (has_hwinf || disk->has_dev || disk->has_serial) {
-        list->next = fs->disk;
-        fs->disk = list;
+        QAPI_LIST_PREPEND(fs->disk, disk);
     } else {
-        qapi_free_GuestDiskAddressList(list);
+        qapi_free_GuestDiskAddress(disk);
     }
 }
 
@@ -1288,7 +1283,6 @@ static void get_disk_deps(const char *disk_dir, GuestDiskInfo *disk)
     disk->has_dependencies = true;
     while ((dep = g_dir_read_name(dp_deps)) != NULL) {
         g_autofree char *dep_dir = NULL;
-        strList *dep_item = NULL;
         char *dev_name;
 
         /* Add dependent disks */
@@ -1296,10 +1290,7 @@ static void get_disk_deps(const char *disk_dir, GuestDiskInfo *disk)
         dev_name = get_device_for_syspath(dep_dir);
         if (dev_name != NULL) {
             g_debug("  adding dependent device: %s", dev_name);
-            dep_item = g_new0(strList, 1);
-            dep_item->value = dev_name;
-            dep_item->next = disk->dependencies;
-            disk->dependencies = dep_item;
+            QAPI_LIST_PREPEND(disk->dependencies, dev_name);
         }
     }
     g_dir_close(dp_deps);
@@ -1318,7 +1309,7 @@ static GuestDiskInfoList *get_disk_partitions(
     const char *disk_name, const char *disk_dir,
     const char *disk_dev)
 {
-    GuestDiskInfoList *item, *ret = list;
+    GuestDiskInfoList *ret = list;
     struct dirent *de_disk;
     DIR *dp_disk = NULL;
     size_t len = strlen(disk_name);
@@ -1352,15 +1343,9 @@ static GuestDiskInfoList *get_disk_partitions(
         partition->name = dev_name;
         partition->partition = true;
         /* Add parent disk as dependent for easier tracking of hierarchy */
-        partition->dependencies = g_new0(strList, 1);
-        partition->dependencies->value = g_strdup(disk_dev);
-        partition->has_dependencies = true;
-
-        item = g_new0(GuestDiskInfoList, 1);
-        item->value = partition;
-        item->next = ret;
-        ret = item;
+        QAPI_LIST_PREPEND(partition->dependencies, g_strdup(disk_dev));
 
+        QAPI_LIST_PREPEND(ret, partition);
     }
     closedir(dp_disk);
 
@@ -1369,7 +1354,7 @@ static GuestDiskInfoList *get_disk_partitions(
 
 GuestDiskInfoList *qmp_guest_get_disks(Error **errp)
 {
-    GuestDiskInfoList *item, *ret = NULL;
+    GuestDiskInfoList *ret = NULL;
     GuestDiskInfo *disk;
     DIR *dp = NULL;
     struct dirent *de = NULL;
@@ -1415,10 +1400,7 @@ GuestDiskInfoList *qmp_guest_get_disks(Error **errp)
         disk->partition = false;
         disk->alias = get_alias_for_syspath(disk_dir);
         disk->has_alias = (disk->alias != NULL);
-        item = g_new0(GuestDiskInfoList, 1);
-        item->value = disk;
-        item->next = ret;
-        ret = item;
+        QAPI_LIST_PREPEND(ret, disk);
 
         /* Get address for non-virtual devices */
         bool is_virtual = is_disk_virtual(disk_dir, &local_err);
@@ -1495,7 +1477,7 @@ GuestFilesystemInfoList *qmp_guest_get_fsinfo(Error **errp)
 {
     FsMountList mounts;
     struct FsMount *mount;
-    GuestFilesystemInfoList *new, *ret = NULL;
+    GuestFilesystemInfoList *ret = NULL;
     Error *local_err = NULL;
 
     QTAILQ_INIT(&mounts);
@@ -1508,10 +1490,7 @@ GuestFilesystemInfoList *qmp_guest_get_fsinfo(Error **errp)
     QTAILQ_FOREACH(mount, &mounts, next) {
         g_debug("Building guest fsinfo for '%s'", mount->dirname);
 
-        new = g_malloc0(sizeof(*ret));
-        new->value = build_guest_fsinfo(mount, &local_err);
-        new->next = ret;
-        ret = new;
+        QAPI_LIST_PREPEND(ret, build_guest_fsinfo(mount, &local_err));
         if (local_err) {
             error_propagate(errp, local_err);
             qapi_free_GuestFilesystemInfoList(ret);
@@ -1777,7 +1756,6 @@ GuestFilesystemTrimResponse *
 qmp_guest_fstrim(bool has_minimum, int64_t minimum, Error **errp)
 {
     GuestFilesystemTrimResponse *response;
-    GuestFilesystemTrimResultList *list;
     GuestFilesystemTrimResult *result;
     int ret = 0;
     FsMountList mounts;
@@ -1801,10 +1779,7 @@ qmp_guest_fstrim(bool has_minimum, int64_t minimum, Error **errp)
         result = g_malloc0(sizeof(*result));
         result->path = g_strdup(mount->dirname);
 
-        list = g_malloc0(sizeof(*list));
-        list->value = result;
-        list->next = response->paths;
-        response->paths = list;
+        QAPI_LIST_PREPEND(response->paths, result);
 
         fd = qemu_open_old(mount->dirname, O_RDONLY);
         if (fd == -1) {
diff --git a/qga/commands-win32.c b/qga/commands-win32.c
index ba1fd07d06..684639bd13 100644
--- a/qga/commands-win32.c
+++ b/qga/commands-win32.c
@@ -874,7 +874,7 @@ err_close:
 static GuestDiskAddressList *build_guest_disk_info(char *guid, Error **errp)
 {
     Error *local_err = NULL;
-    GuestDiskAddressList *list = NULL, *cur_item = NULL;
+    GuestDiskAddressList *list = NULL;
     GuestDiskAddress *disk = NULL;
     int i;
     HANDLE vol_h;
@@ -926,10 +926,8 @@ static GuestDiskAddressList *build_guest_disk_info(char *guid, Error **errp)
                 error_free(local_err);
                 goto out;
             }
-            list = g_malloc0(sizeof(*list));
-            list->value = disk;
+            QAPI_LIST_PREPEND(list, disk);
             disk = NULL;
-            list->next = NULL;
             goto out;
         } else {
             error_setg_win32(errp, GetLastError(),
@@ -960,11 +958,8 @@ static GuestDiskAddressList *build_guest_disk_info(char *guid, Error **errp)
             error_propagate(errp, local_err);
             goto out;
         }
-        cur_item = g_malloc0(sizeof(*list));
-        cur_item->value = disk;
+        QAPI_LIST_PREPEND(list, disk);
         disk = NULL;
-        cur_item->next = list;
-        list = cur_item;
     }
 
 
@@ -982,7 +977,7 @@ out:
 GuestDiskInfoList *qmp_guest_get_disks(Error **errp)
 {
     ERRP_GUARD();
-    GuestDiskInfoList *new = NULL, *ret = NULL;
+    GuestDiskInfoList *ret = NULL;
     HDEVINFO dev_info;
     SP_DEVICE_INTERFACE_DATA dev_iface_data;
     int i;
@@ -1064,10 +1059,7 @@ GuestDiskInfoList *qmp_guest_get_disks(Error **errp)
             disk->has_address = true;
         }
 
-        new = g_malloc0(sizeof(GuestDiskInfoList));
-        new->value = disk;
-        new->next = ret;
-        ret = new;
+        QAPI_LIST_PREPEND(ret, disk);
     }
 
     SetupDiDestroyDeviceInfoList(dev_info);
@@ -1165,7 +1157,7 @@ free:
 GuestFilesystemInfoList *qmp_guest_get_fsinfo(Error **errp)
 {
     HANDLE vol_h;
-    GuestFilesystemInfoList *new, *ret = NULL;
+    GuestFilesystemInfoList *ret = NULL;
     char guid[256];
 
     vol_h = FindFirstVolume(guid, sizeof(guid));
@@ -1183,10 +1175,7 @@ GuestFilesystemInfoList *qmp_guest_get_fsinfo(Error **errp)
             error_free(local_err);
             continue;
         }
-        new = g_malloc(sizeof(*ret));
-        new->value = info;
-        new->next = ret;
-        ret = new;
+        QAPI_LIST_PREPEND(ret, info);
     } while (FindNextVolume(vol_h, guid, sizeof(guid)));
 
     if (GetLastError() != ERROR_NO_MORE_FILES) {
@@ -1330,7 +1319,6 @@ qmp_guest_fstrim(bool has_minimum, int64_t minimum, Error **errp)
 
     do {
         GuestFilesystemTrimResult *res;
-        GuestFilesystemTrimResultList *list;
         PWCHAR uc_path;
         DWORD char_count = 0;
         char *path, *out;
@@ -1369,11 +1357,7 @@ qmp_guest_fstrim(bool has_minimum, int64_t minimum, Error **errp)
 
         res->path = path;
 
-        list = g_new0(GuestFilesystemTrimResultList, 1);
-        list->value = res;
-        list->next = resp->paths;
-
-        resp->paths = list;
+        QAPI_LIST_PREPEND(resp->paths, res);
 
         memset(argv, 0, sizeof(argv));
         argv[0] = (gchar *)"defrag.exe";
diff --git a/qga/commands.c b/qga/commands.c
index 3dcd5fbe5c..e866fc7081 100644
--- a/qga/commands.c
+++ b/qga/commands.c
@@ -66,17 +66,13 @@ static void qmp_command_info(const QmpCommand *cmd, void *opaque)
 {
     GuestAgentInfo *info = opaque;
     GuestAgentCommandInfo *cmd_info;
-    GuestAgentCommandInfoList *cmd_info_list;
 
     cmd_info = g_new0(GuestAgentCommandInfo, 1);
     cmd_info->name = g_strdup(qmp_command_name(cmd));
     cmd_info->enabled = qmp_command_is_enabled(cmd);
     cmd_info->success_response = qmp_has_success_response(cmd);
 
-    cmd_info_list = g_new0(GuestAgentCommandInfoList, 1);
-    cmd_info_list->value = cmd_info;
-    cmd_info_list->next = info->supported_commands;
-    info->supported_commands = cmd_info_list;
+    QAPI_LIST_PREPEND(info->supported_commands, cmd_info);
 }
 
 struct GuestAgentInfo *qmp_guest_info(Error **errp)