accounts/usbwallet: skip support on iOS altogether

accounts/usbwallet/ledger.go

@@ -18,6 +18,8 @@
 // wallets. The wire protocol spec can be found in the Ledger Blue GitHub repo:
 // https://raw.githubusercontent.com/LedgerHQ/blue-app-eth/master/doc/ethapp.asc
 
+// +build !ios
+
 package usbwallet
 
 import (

accounts/usbwallet/ledger_test.go

@@ -14,6 +14,8 @@
 // You should have received a copy of the GNU Lesser General Public License
 // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
 
+// +build !ios
+
 package usbwallet
 
 /*

accounts/usbwallet/usbwallet.go

@@ -14,6 +14,8 @@
 // You should have received a copy of the GNU Lesser General Public License
 // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
 
+// +build !ios
+
 // Package usbwallet implements support for USB hardware wallets.
 package usbwallet
 

accounts/usbwallet/usbwallet_ios.go

@@ -0,0 +1,38 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+// This file contains the implementation for interacting with the Ledger hardware
+// wallets. The wire protocol spec can be found in the Ledger Blue GitHub repo:
+// https://raw.githubusercontent.com/LedgerHQ/blue-app-eth/master/doc/ethapp.asc
+
+// +build ios
+
+package usbwallet
+
+import (
+	"errors"
+
+	"github.com/ethereum/go-ethereum/accounts"
+)
+
+// Here be dragons! There is no USB support on iOS.
+
+// ErrIOSNotSupported is returned for all USB hardware backends on iOS.
+var ErrIOSNotSupported = errors.New("no USB support on iOS")
+
+func NewLedgerHub() (accounts.Backend, error) {
+	return nil, ErrIOSNotSupported
+}