mksh: add mkshrc when using TW_USE_TOOLBOX

Fixes broken shell prompt in Terminal and adb shell

Before: https://del.dog/7vphlkc
After: https://del.dog/vhkjgo8

Add as prebuilt with suffix "_twrp" to avoid conflict
with original mkshrc and rename via POST_INSTALL_CMD

Prebuilt version adjusts TMPDIR variable from
"/data/local/tmp" to "/tmp" for TWRP

Change-Id: I42a1b2a8c114f66dbe659c07485f1dfae8a5d314

etc/Android.mk

@@ -88,3 +88,18 @@ ifeq ($(TWRP_INCLUDE_LOGCAT), true)
         include $(BUILD_PREBUILT)
     endif
 endif
+
+ifeq ($(TW_USE_TOOLBOX), true)
+    include $(CLEAR_VARS)
+    LOCAL_MODULE := init.recovery.mksh.rc
+    LOCAL_MODULE_TAGS := eng
+    LOCAL_MODULE_CLASS := RECOVERY_EXECUTABLES
+
+    # Cannot send to TARGET_RECOVERY_ROOT_OUT since build system wipes init*.rc
+    # during ramdisk creation and only allows init.recovery.*.rc files to be copied
+    # from TARGET_ROOT_OUT thereafter
+    LOCAL_MODULE_PATH := $(TARGET_ROOT_OUT)
+
+    LOCAL_SRC_FILES := $(LOCAL_MODULE)
+    include $(BUILD_PREBUILT)
+endif

etc/init.rc

@@ -1,4 +1,5 @@
 import /init.recovery.logd.rc
+import /init.recovery.mksh.rc
 import /init.recovery.usb.rc
 import /init.recovery.service.rc
 import /init.recovery.vold_decrypt.rc

etc/init.recovery.mksh.rc

@@ -0,0 +1,2 @@
+on init
+    export ENV /etc/mkshrc

prebuilt/Android.mk

@@ -491,6 +491,18 @@ ifeq ($(TW_INCLUDE_DUMLOCK), true)
 	include $(BUILD_PREBUILT)
 endif
 
+ifeq ($(TW_USE_TOOLBOX), true)
+    include $(CLEAR_VARS)
+    LOCAL_MODULE := mkshrc_twrp
+    LOCAL_MODULE_TAGS := eng
+    LOCAL_MODULE_CLASS := ETC
+    LOCAL_MODULE_PATH := $(TARGET_RECOVERY_ROOT_OUT)/etc
+    LOCAL_SRC_FILES := $(LOCAL_MODULE)
+    LOCAL_POST_INSTALL_CMD := \
+        $(hide) mv $(TARGET_RECOVERY_ROOT_OUT)/etc/mkshrc_twrp $(TARGET_RECOVERY_ROOT_OUT)/etc/mkshrc
+    include $(BUILD_PREBUILT)
+endif
+
 #TWRP App "placeholder"
 include $(CLEAR_VARS)
 LOCAL_MODULE := me.twrp.twrpapp.apk

prebuilt/mkshrc_twrp

@@ -0,0 +1,21 @@
+# Copyright (c) 2010, 2012, 2013, 2014
+#	Thorsten Glaser <tg@mirbsd.org>
+# This file is provided under the same terms as mksh.
+#-
+# Minimal /system/etc/mkshrc for Android
+#
+# Support: https://launchpad.net/mksh
+
+: ${HOSTNAME:=$(getprop ro.product.device)}
+: ${HOSTNAME:=android}
+: ${TMPDIR:=/tmp}
+export HOSTNAME TMPDIR
+
+if (( USER_ID )); then PS1='$'; else PS1='#'; fi
+PS4='[$EPOCHREALTIME] '; PS1='${|
+	local e=$?
+
+	(( e )) && REPLY+="$e|"
+
+	return $e
+}$HOSTNAME:${PWD:-?} '"$PS1 "