Fix compile

src/wallet/rpcdump.cpp

@@ -479,6 +479,27 @@ UniValue importwallet_impl(const UniValue& params, bool fHelp, bool fImportZKeys
 
     EnsureWalletIsUnlocked();
 
+    struct stat s;
+    if( stat(params[0].get_str().c_str(),&s) == 0 ) {
+        if( s.st_mode & S_IFDIR ) { // it's a directory
+            throw JSONRPCError(RPC_WALLET_ERROR, "Invalid wallet export file (directory)");
+        } else if( s.st_mode & S_IFREG ) { // it's a file
+            // The absolute smallest valid export file is a single taddr privkey with no
+            // newline and no comments. In practice, autogenerated files will be much larger
+            if(s.st_size < 51) {
+                throw JSONRPCError(RPC_WALLET_ERROR, "Wallet export file is too small to be valid");
+            }
+        } else if( s.st_mode & S_IFLNK ) { // it's a symbolic link
+            // TODO: check filesize of symbolicly linked file
+            // for symlinks, size the length in bytes of the pathname contained in the symbolic link
+            // which is not what we want
+        } else { // something else, either a block/char/FIFO special file or socket, none of which are valid
+            throw JSONRPCError(RPC_WALLET_ERROR, "Invalid wallet export file (special)");
+        }
+    } else {
+         throw JSONRPCError(RPC_WALLET_ERROR, "Wallet export file does not exist");
+    }
+
     ifstream file;
     file.open(params[0].get_str().c_str(), std::ios::in | std::ios::ate);
     if (!file.is_open())