interface: Refactor udev bridge to helper func

Mechanical move to break up udevIfaceGetIfaceDef() into different
helpers for each of the interface types to hopefully make the code
easier to follow. This moves the bridge code to
udevIfaceGetIfaceDefBridge().

src/interface/interface_backend_udev.c

@@ -41,6 +41,8 @@ typedef enum {
     VIR_UDEV_IFACE_ALL
 } virUdevStatus ;
 
+static virInterfaceDef *udevIfaceGetIfaceDef(struct udev *udev, const char *name);
+
 static const char *
 virUdevStatusString(virUdevStatus status)
 {
@@ -492,14 +494,14 @@ err:
 }
 
 /**
- * Helper function for our use of scandir()
+ * Helper function for finding bridge members using scandir()
  *
  * @param entry - directory entry passed by scandir()
  *
  * @return 1 if we want to add it to scandir's list, 0 if not.
  */
 static int
-udevIfaceScanDirFilter(const struct dirent *entry)
+udevIfaceBridgeScanDirFilter(const struct dirent *entry)
 {
     if (STREQ(entry->d_name, ".") || STREQ(entry->d_name, ".."))
         return 0;
@@ -538,18 +540,95 @@ udevIfaceFreeIfaceDef(virInterfaceDef *ifacedef)
     VIR_FREE(ifacedef);
 }
 
+static int
+ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) ATTRIBUTE_NONNULL(3)
+ATTRIBUTE_NONNULL(4) ATTRIBUTE_RETURN_CHECK
+udevIfaceGetIfaceDefBridge(struct udev *udev,
+                           struct udev_device *dev,
+                           const char *name,
+                           virInterfaceDef *ifacedef)
+{
+    struct dirent **member_list = NULL;
+    int member_count = 0;
+    char *member_path;
+    const char *stp_str;
+    int stp;
+    int i;
+
+    /* Set our type to Bridge  */
+    ifacedef->type = VIR_INTERFACE_TYPE_BRIDGE;
+
+    /* Bridge specifics */
+    ifacedef->data.bridge.delay =
+        strdup(udev_device_get_sysattr_value(dev, "bridge/forward_delay"));
+    if (!ifacedef->data.bridge.delay) {
+        virReportOOMError();
+        goto cleanup;
+    }
+
+    stp_str = udev_device_get_sysattr_value(dev, "bridge/stp_state");
+    if (virStrToLong_i(stp_str, NULL, 10, &stp) < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR,
+                _("Could not parse STP state '%s'"), stp_str);
+        goto cleanup;
+    }
+    ifacedef->data.bridge.stp = stp;
+
+    /* Members of the bridge */
+    if (virAsprintf(&member_path, "%s/%s",
+                udev_device_get_syspath(dev), "brif") < 0) {
+        virReportOOMError();
+        goto cleanup;
+    }
+
+    /* Get each member of the bridge */
+    member_count = scandir(member_path, &member_list,
+            udevIfaceBridgeScanDirFilter, alphasort);
+
+    /* Don't need the path anymore */
+    VIR_FREE(member_path);
+
+    if (member_count < 0) {
+        virReportSystemError(errno,
+                _("Could not get members of bridge '%s'"),
+                name);
+        goto cleanup;
+    }
+
+    /* Allocate our list of member devices */
+    if (VIR_ALLOC_N(ifacedef->data.bridge.itf, member_count) < 0) {
+        virReportOOMError();
+        goto cleanup;
+    }
+    ifacedef->data.bridge.nbItf = member_count;
+
+    for (i = 0; i < member_count; i++) {
+        ifacedef->data.bridge.itf[i] =
+            udevIfaceGetIfaceDef(udev, member_list[i]->d_name);
+        VIR_FREE(member_list[i]);
+    }
+
+    VIR_FREE(member_list);
+
+    return 0;
+
+cleanup:
+    for (i = 0; i < member_count; i++) {
+        VIR_FREE(member_list[i]);
+    }
+    VIR_FREE(member_list);
+
+    return -1;
+}
 
 static virInterfaceDef * ATTRIBUTE_NONNULL(1)
-udevIfaceGetIfaceDef(struct udev *udev, char *name)
+udevIfaceGetIfaceDef(struct udev *udev, const char *name)
 {
     struct udev_device *dev = NULL;
     virInterfaceDef *ifacedef;
     unsigned int mtu;
     const char *mtu_str;
     char *vlan_parent_dev = NULL;
-    struct dirent **member_list = NULL;
-    int member_count = 0;
-    int i;
 
     /* Allocate our interface definition structure */
     if (VIR_ALLOC(ifacedef) < 0) {
@@ -629,66 +708,8 @@ udevIfaceGetIfaceDef(struct udev *udev, char *name)
         ifacedef->data.vlan.tag = vid;
         ifacedef->data.vlan.devname = vlan_parent_dev;
     } else if (STREQ_NULLABLE(udev_device_get_devtype(dev), "bridge")) {
-        /* Check if its a bridge device */
+        if (udevIfaceGetIfaceDefBridge(udev, dev, name, ifacedef) < 0)
-        char *member_path;
-        const char *stp_str;
-        int stp;
-
-        /* Set our type to Bridge  */
-        ifacedef->type = VIR_INTERFACE_TYPE_BRIDGE;
-
-        /* Bridge specifics */
-        ifacedef->data.bridge.delay =
-            strdup(udev_device_get_sysattr_value(dev, "bridge/forward_delay"));
-        if (!ifacedef->data.bridge.delay) {
-            virReportOOMError();
             goto cleanup;
-        }
-
-        stp_str = udev_device_get_sysattr_value(dev, "bridge/stp_state");
-        if (virStrToLong_i(stp_str, NULL, 10, &stp) < 0) {
-            virReportError(VIR_ERR_INTERNAL_ERROR,
-                           _("Could not parse STP state '%s'"), stp_str);
-            goto cleanup;
-        }
-        ifacedef->data.bridge.stp = stp;
-
-        /* Members of the bridge */
-        if (virAsprintf(&member_path, "%s/%s",
-                        udev_device_get_syspath(dev), "brif") < 0) {
-            virReportOOMError();
-            goto cleanup;
-        }
-
-        /* Get each member of the bridge */
-        member_count = scandir(member_path, &member_list,
-                               udevIfaceScanDirFilter, alphasort);
-
-        /* Don't need the path anymore */
-        VIR_FREE(member_path);
-
-        if (member_count < 0) {
-            virReportSystemError(errno,
-                                 _("Could not get members of bridge '%s'"),
-                                 name);
-            goto cleanup;
-        }
-
-        /* Allocate our list of member devices */
-        if (VIR_ALLOC_N(ifacedef->data.bridge.itf, member_count) < 0) {
-            virReportOOMError();
-            goto cleanup;
-        }
-        ifacedef->data.bridge.nbItf = member_count;
-
-        for (i = 0; i < member_count; i++) {
-            ifacedef->data.bridge.itf[i] =
-                udevIfaceGetIfaceDef(udev, member_list[i]->d_name);
-            VIR_FREE(member_list[i]);
-        }
-
-        VIR_FREE(member_list);
-
     } else {
         /* Set our type to ethernet */
         ifacedef->type = VIR_INTERFACE_TYPE_ETHERNET;
@@ -700,10 +721,6 @@ udevIfaceGetIfaceDef(struct udev *udev, char *name)
 
 cleanup:
     udev_device_unref(dev);
-    for (i = 0; i < member_count; i++) {
-        VIR_FREE(member_list[i]);
-    }
-    VIR_FREE(member_list);
 
     udevIfaceFreeIfaceDef(ifacedef);