[Qemu-devel] [PATCH 07/19] Convert netdev client types to use an enumeration

["Daniel P. Berrange" <berrange@redhat.com>]

Declare an enumeration for all netdev client types, values
matching indexes in the net_client_types array. Use the
enum helpers for the string <-> int conversion of client types.

Before:

  $ qemu -net type=foo,sfs
  qemu: -net type=foo,sfs: Parameter 'type' expects a network client type

After:

  $ qemu -net type=foo,sfs
  qemu: -net type=foo,sfs: Parameter 'type' expects none, nic, user, tap, socket, dump

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
---
 net.c |  124 ++++++++++++++++++++++++++++++++++++++--------------------------
 1 files changed, 74 insertions(+), 50 deletions(-)

diff --git a/net.c b/net.c
index efa8b3d..5349001 100644
--- a/net.c
+++ b/net.c
@@ -42,6 +42,36 @@ static QTAILQ_HEAD(, VLANClientState) non_vlan_clients;
 
 int default_net = 1;
 
+enum {
+    NET_CLIENT_NONE,
+    NET_CLIENT_NIC,
+#ifdef CONFIG_SLIRP
+    NET_CLIENT_USER,
+#endif
+    NET_CLIENT_TAP,
+    NET_CLIENT_SOCKET,
+#ifdef CONFIG_VDE
+    NET_CLIENT_VDE,
+#endif
+    NET_CLIENT_DUMP,
+
+    NET_CLIENT_LAST
+};
+
+QEMU_ENUM_DECL(qemu_net_type);
+QEMU_ENUM_IMPL(qemu_net_type, NET_CLIENT_LAST,
+	       "none",
+	       "nic",
+#ifdef CONFIG_SLIRP
+	       "user",
+#endif
+	       "tap",
+	       "socket",
+#ifdef CONFIG_VDE
+	       "vde",
+#endif
+	       "dump");
+
 /***********************************************************/
 /* network device redirectors */
 
@@ -844,18 +874,15 @@ typedef int (*net_client_init_func)(QemuOpts *opts,
 #define NET_MAX_DESC 20
 
 static const struct {
-    const char *type;
     net_client_init_func init;
     QemuOptDesc desc[NET_MAX_DESC];
 } net_client_types[] = {
-    {
-        .type = "none",
+    { /* NET_CLIENT_NONE */
         .desc = {
             NET_COMMON_PARAMS_DESC,
             { /* end of list */ }
         },
-    }, {
-        .type = "nic",
+    }, { /* NET_CLIENT_NIC */
         .init = net_init_nic,
         .desc = {
             NET_COMMON_PARAMS_DESC,
@@ -884,8 +911,7 @@ static const struct {
             { /* end of list */ }
         },
 #ifdef CONFIG_SLIRP
-    }, {
-        .type = "user",
+    }, { /* NET_CLIENT_USER */
         .init = net_init_slirp,
         .desc = {
             NET_COMMON_PARAMS_DESC,
@@ -945,8 +971,7 @@ static const struct {
             { /* end of list */ }
         },
 #endif
-    }, {
-        .type = "tap",
+    }, { /* NET_CLIENT_TAP */
         .init = net_init_tap,
         .desc = {
             NET_COMMON_PARAMS_DESC,
@@ -988,8 +1013,7 @@ static const struct {
 #endif /* _WIN32 */
             { /* end of list */ }
         },
-    }, {
-        .type = "socket",
+    }, { /* NET_CLIENT_SOCKET */
         .init = net_init_socket,
         .desc = {
             NET_COMMON_PARAMS_DESC,
@@ -1013,8 +1037,7 @@ static const struct {
             { /* end of list */ }
         },
 #ifdef CONFIG_VDE
-    }, {
-        .type = "vde",
+    }, { /* NET_CLIENT_VDE */
         .init = net_init_vde,
         .desc = {
             NET_COMMON_PARAMS_DESC,
@@ -1038,8 +1061,7 @@ static const struct {
             { /* end of list */ }
         },
 #endif
-    }, {
-        .type = "dump",
+    }, { /* NET_CLIENT_DUMP */
         .init = net_init_dump,
         .desc = {
             NET_COMMON_PARAMS_DESC,
@@ -1055,30 +1077,41 @@ static const struct {
             { /* end of list */ }
         },
     },
-    { /* end of list */ }
 };
+verify(ARRAY_SIZE(net_client_types) == NET_CLIENT_LAST);
 
 int net_client_init(Monitor *mon, QemuOpts *opts, int is_netdev)
 {
     const char *name;
-    const char *type;
-    int i;
+    const char *typestr;
+    VLANState *vlan = NULL;
+    int type;
 
-    type = qemu_opt_get(opts, "type");
-    if (!type) {
+    typestr = qemu_opt_get(opts, "type");
+    if (!typestr) {
         qerror_report(QERR_MISSING_PARAMETER, "type");
         return -1;
     }
+    type = qemu_net_type_from_string(typestr);
+
+    if (type < 0) {
+	char *valid = qemu_net_type_to_string_list();
+	qerror_report(QERR_INVALID_PARAMETER_VALUE, "type",
+		      valid);
+	qemu_free(valid);
+	return -1;
+    }
 
     if (is_netdev) {
-        if (strcmp(type, "tap") != 0 &&
+	if (type < 0 ||
+	    (type != NET_CLIENT_TAP &&
 #ifdef CONFIG_SLIRP
-            strcmp(type, "user") != 0 &&
+	     type != NET_CLIENT_USER &&
 #endif
 #ifdef CONFIG_VDE
-            strcmp(type, "vde") != 0 &&
+	     type != NET_CLIENT_VDE &&
 #endif
-            strcmp(type, "socket") != 0) {
+	     type != NET_CLIENT_SOCKET)) {
             qerror_report(QERR_INVALID_PARAMETER_VALUE, "type",
                           "a netdev backend type");
             return -1;
@@ -1103,35 +1136,26 @@ int net_client_init(Monitor *mon, QemuOpts *opts, int is_netdev)
         name = qemu_opt_get(opts, "name");
     }
 
-    for (i = 0; net_client_types[i].type != NULL; i++) {
-        if (!strcmp(net_client_types[i].type, type)) {
-            VLANState *vlan = NULL;
-
-            if (qemu_opts_validate(opts, &net_client_types[i].desc[0]) == -1) {
-                return -1;
-            }
-
-            /* Do not add to a vlan if it's a -netdev or a nic with a
-             * netdev= parameter. */
-            if (!(is_netdev ||
-                  (strcmp(type, "nic") == 0 && qemu_opt_get(opts, "netdev")))) {
-                vlan = qemu_find_vlan(qemu_opt_get_number(opts, "vlan", 0), 1);
-            }
+    if (qemu_opts_validate(opts, &net_client_types[type].desc[0]) == -1) {
+	return -1;
+    }
 
-            if (net_client_types[i].init) {
-                if (net_client_types[i].init(opts, mon, name, vlan) < 0) {
-                    /* TODO push error reporting into init() methods */
-                    qerror_report(QERR_DEVICE_INIT_FAILED, type);
-                    return -1;
-                }
-            }
-            return 0;
-        }
+    /* Do not add to a vlan if it's a -netdev or a nic with a
+     * netdev= parameter. */
+    if (!(is_netdev ||
+	  (type == NET_CLIENT_NIC && qemu_opt_get(opts, "netdev")))) {
+	vlan = qemu_find_vlan(qemu_opt_get_number(opts, "vlan", 0), 1);
     }
 
-    qerror_report(QERR_INVALID_PARAMETER_VALUE, "type",
-                  "a network client type");
-    return -1;
+    if (net_client_types[type].init) {
+	if (net_client_types[type].init(opts, mon, name, vlan) < 0) {
+	    /* TODO push error reporting into init() methods */
+	    qerror_report(QERR_DEVICE_INIT_FAILED,
+			  qemu_net_type_to_string(type));
+	    return -1;
+	}
+    }
+    return 0;
 }
 
 static int net_host_check_device(const char *device)
-- 
1.6.6.1