C++ class for device-specific code

Replace the device-specific functions with a class.  Move some of the
key handling (for log visibility toggling and rebooting) into the UI
class.  Fix up the key handling so there is less crosstalk between the
immediate keys and the queued keys (an increasing annoyance on
button-limited devices).

Change-Id: I698f6fd21c67a1e55429312a0484b6c393cad46f

1 files changed, 112 insertions, 0 deletions

diff --git a/device.h b/device.h
new file mode 100644
index 0000000..8096a8d
--- /dev/null
+++ b/device.h
@@ -0,0 +1,112 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _RECOVERY_DEVICE_H
+#define _RECOVERY_DEVICE_H
+
+#include "ui.h"
+
+class Device {
+  public:
+    virtual ~Device() { }
+
+    // Called to obtain the UI object that should be used to display
+    // the recovery user interface for this device.  You should not
+    // have called Init() on the UI object already, the caller will do
+    // that after this method returns.
+    virtual RecoveryUI* GetUI() = 0;
+
+    // Called when recovery starts up (after the UI has been obtained
+    // and initialized and after the arguments have been parsed, but
+    // before anything else).
+    virtual void StartRecovery() { };
+
+    // enum KeyAction { NONE, TOGGLE, REBOOT };
+
+    // // Called in the input thread when a new key (key_code) is
+    // // pressed.  *key_pressed is an array of KEY_MAX+1 bytes
+    // // indicating which other keys are already pressed.  Return a
+    // // KeyAction to indicate action should be taken immediately.
+    // // These actions happen when recovery is not waiting for input
+    // // (eg, in the midst of installing a package).
+    // virtual KeyAction CheckImmediateKeyAction(volatile char* key_pressed, int key_code) = 0;
+
+    // Called from the main thread when recovery is at the main menu
+    // and waiting for input, and a key is pressed.  (Note that "at"
+    // the main menu does not necessarily mean the menu is visible;
+    // recovery will be at the main menu with it invisible after an
+    // unsuccessful operation [ie OTA package failure], or if recovery
+    // is started with no command.)
+    //
+    // key is the code of the key just pressed.  (You can call
+    // IsKeyPressed() on the RecoveryUI object you returned from GetUI
+    // if you want to find out if other keys are held down.)
+    //
+    // visible is true if the menu is visible.
+    //
+    // Return one of the defined constants below in order to:
+    //
+    //   - move the menu highlight (kHighlight{Up,Down})
+    //   - invoke the highlighted item (kInvokeItem)
+    //   - do nothing (kNoAction)
+    //   - invoke a specific action (a menu position: any non-negative number)
+    virtual int HandleMenuKey(int key, int visible) = 0;
+
+    enum BuiltinAction { NO_ACTION, REBOOT, APPLY_EXT, APPLY_CACHE,
+                         WIPE_DATA, WIPE_CACHE };
+
+    // Perform a recovery action selected from the menu.
+    // 'menu_position' will be the item number of the selected menu
+    // item, or a non-negative number returned from
+    // device_handle_key().  The menu will be hidden when this is
+    // called; implementations can call ui_print() to print
+    // information to the screen.  If the menu position is one of the
+    // builtin actions, you can just return the corresponding enum
+    // value.  If it is an action specific to your device, you
+    // actually perform it here and return NO_ACTION.
+    virtual BuiltinAction InvokeMenuItem(int menu_position) = 0;
+
+    static const int kNoAction = -1;
+    static const int kHighlightUp = -2;
+    static const int kHighlightDown = -3;
+    static const int kInvokeItem = -4;
+
+    // Called when we do a wipe data/factory reset operation (either via a
+    // reboot from the main system with the --wipe_data flag, or when the
+    // user boots into recovery manually and selects the option from the
+    // menu.)  Can perform whatever device-specific wiping actions are
+    // needed.  Return 0 on success.  The userdata and cache partitions
+    // are erased AFTER this returns (whether it returns success or not).
+    virtual int WipeData() { return 0; }
+
+    // Return the headers (an array of strings, one per line,
+    // NULL-terminated) for the main menu.  Typically these tell users
+    // what to push to move the selection and invoke the selected
+    // item.
+    virtual const char* const* GetMenuHeaders() = 0;
+
+    // Return the list of menu items (an array of strings,
+    // NULL-terminated).  The menu_position passed to InvokeMenuItem
+    // will correspond to the indexes into this array.
+    virtual const char* const* GetMenuItems() = 0;
+};
+
+// The device-specific library must define this function (or the
+// default one will be used, if there is no device-specific library).
+// It returns the Device object that recovery should use.
+Device* make_device();
+
+#endif  // _DEVICE_H