diff --git a/twinstallorig.cpp b/twinstallorig.cpp
new file mode 100644
index 0000000..60d76a5
--- /dev/null
+++ b/twinstallorig.cpp
@@ -0,0 +1,424 @@
+/*
+	Copyright 2012 to 2016 bigbiff/Dees_Troy TeamWin
+	This file is part of TWRP/TeamWin Recovery Project.
+
+	TWRP is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	TWRP 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 General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with TWRP.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include <string.h>
+#include <stdio.h>
+
+#include "twcommon.h"
+#include "mtdutils/mounts.h"
+#include "mtdutils/mtdutils.h"
+#include "minzip/SysUtil.h"
+#include "minzip/Zip.h"
+#ifdef USE_OLD_VERIFIER
+#include "verifier24/verifier.h"
+#else
+#include "verifier.h"
+#endif
+#include "variables.h"
+#include "data.hpp"
+#include "partitions.hpp"
+#include "twrpDigestDriver.hpp"
+#include "twrpDigest/twrpDigest.hpp"
+#include "twrpDigest/twrpMD5.hpp"
+#include "twrp-functions.hpp"
+#include "gui/gui.hpp"
+#include "gui/pages.hpp"
+#include "legacy_property_service.h"
+#include "twinstall.h"
+#include "installcommand.h"
+extern "C" {
+	#include "gui/gui.h"
+}
+
+#define AB_OTA "payload_properties.txt"
+
+static const char* properties_path = "/dev/__properties__";
+static const char* properties_path_renamed = "/dev/__properties_kk__";
+static bool legacy_props_env_initd = false;
+static bool legacy_props_path_modified = false;
+
+enum zip_type {
+	UNKNOWN_ZIP_TYPE = 0,
+	UPDATE_BINARY_ZIP_TYPE,
+	AB_OTA_ZIP_TYPE,
+	TWRP_THEME_ZIP_TYPE
+};
+
+// to support pre-KitKat update-binaries that expect properties in the legacy format
+static int switch_to_legacy_properties()
+{
+	if (!legacy_props_env_initd) {
+		if (legacy_properties_init() != 0)
+			return -1;
+
+		char tmp[32];
+		int propfd, propsz;
+		legacy_get_property_workspace(&propfd, &propsz);
+		sprintf(tmp, "%d,%d", dup(propfd), propsz);
+		setenv("ANDROID_PROPERTY_WORKSPACE", tmp, 1);
+		legacy_props_env_initd = true;
+	}
+
+	if (TWFunc::Path_Exists(properties_path)) {
+		// hide real properties so that the updater uses the envvar to find the legacy format properties
+		if (rename(properties_path, properties_path_renamed) != 0) {
+			LOGERR("Renaming %s failed: %s\n", properties_path, strerror(errno));
+			return -1;
+		} else {
+			legacy_props_path_modified = true;
+		}
+	}
+
+	return 0;
+}
+
+static int switch_to_new_properties()
+{
+	if (TWFunc::Path_Exists(properties_path_renamed)) {
+		if (rename(properties_path_renamed, properties_path) != 0) {
+			LOGERR("Renaming %s failed: %s\n", properties_path_renamed, strerror(errno));
+			return -1;
+		} else {
+			legacy_props_path_modified = false;
+		}
+	}
+
+	return 0;
+}
+
+static int Install_Theme(const char* path, ZipArchive *Zip) {
+#ifdef TW_OEM_BUILD // We don't do custom themes in OEM builds
+	mzCloseZipArchive(Zip);
+	return INSTALL_CORRUPT;
+#else
+	const ZipEntry* xml_location = mzFindZipEntry(Zip, "ui.xml");
+
+	mzCloseZipArchive(Zip);
+	if (xml_location == NULL) {
+		return INSTALL_CORRUPT;
+	}
+	if (!PartitionManager.Mount_Settings_Storage(true))
+		return INSTALL_ERROR;
+	string theme_path = DataManager::GetSettingsStoragePath();
+	theme_path += "/TWRP/theme";
+	if (!TWFunc::Path_Exists(theme_path)) {
+		if (!TWFunc::Recursive_Mkdir(theme_path)) {
+			return INSTALL_ERROR;
+		}
+	}
+	theme_path += "/ui.zip";
+	if (TWFunc::copy_file(path, theme_path, 0644) != 0) {
+		return INSTALL_ERROR;
+	}
+	LOGINFO("Installing custom theme '%s' to '%s'\n", path, theme_path.c_str());
+	PageManager::RequestReload();
+	return INSTALL_SUCCESS;
+#endif
+}
+
+static int Prepare_Update_Binary(const char *path, ZipArchive *Zip, int* wipe_cache) {
+	const ZipEntry* binary_location = mzFindZipEntry(Zip, ASSUMED_UPDATE_BINARY_NAME);
+	int binary_fd, ret_val;
+
+	if (binary_location == NULL) {
+		return INSTALL_CORRUPT;
+	}
+
+	// Delete any existing updater
+	if (TWFunc::Path_Exists(TMP_UPDATER_BINARY_PATH) && unlink(TMP_UPDATER_BINARY_PATH) != 0) {
+		LOGINFO("Unable to unlink '%s': %s\n", TMP_UPDATER_BINARY_PATH, strerror(errno));
+	}
+
+	binary_fd = creat(TMP_UPDATER_BINARY_PATH, 0755);
+	if (binary_fd < 0) {
+		LOGERR("Could not create file for updater extract in '%s': %s\n", TMP_UPDATER_BINARY_PATH, strerror(errno));
+		mzCloseZipArchive(Zip);
+		return INSTALL_ERROR;
+	}
+
+	ret_val = mzExtractZipEntryToFile(Zip, binary_location, binary_fd);
+	close(binary_fd);
+
+	if (!ret_val) {
+		mzCloseZipArchive(Zip);
+		LOGERR("Could not extract '%s'\n", ASSUMED_UPDATE_BINARY_NAME);
+		return INSTALL_ERROR;
+	}
+
+	// If exists, extract file_contexts from the zip file
+	const ZipEntry* selinx_contexts = mzFindZipEntry(Zip, "file_contexts");
+	if (selinx_contexts == NULL) {
+		mzCloseZipArchive(Zip);
+		LOGINFO("Zip does not contain SELinux file_contexts file in its root.\n");
+	} else {
+		string output_filename = "/file_contexts";
+		LOGINFO("Zip contains SELinux file_contexts file in its root. Extracting to %s\n", output_filename.c_str());
+		// Delete any file_contexts
+		if (TWFunc::Path_Exists(output_filename) && unlink(output_filename.c_str()) != 0) {
+			LOGINFO("Unable to unlink '%s': %s\n", output_filename.c_str(), strerror(errno));
+		}
+
+		int file_contexts_fd = creat(output_filename.c_str(), 0644);
+		if (file_contexts_fd < 0) {
+			LOGERR("Could not extract to '%s': %s\n", output_filename.c_str(), strerror(errno));
+			mzCloseZipArchive(Zip);
+			return INSTALL_ERROR;
+		}
+
+		ret_val = mzExtractZipEntryToFile(Zip, selinx_contexts, file_contexts_fd);
+		close(file_contexts_fd);
+
+		if (!ret_val) {
+			mzCloseZipArchive(Zip);
+			LOGERR("Could not extract '%s'\n", output_filename.c_str());
+			return INSTALL_ERROR;
+		}
+	}
+	mzCloseZipArchive(Zip);
+	return INSTALL_SUCCESS;
+}
+
+static int Run_Update_Binary(const char *path, ZipArchive *Zip, int* wipe_cache, zip_type ztype) {
+	int ret_val, pipe_fd[2], status, zip_verify;
+	char buffer[1024];
+	FILE* child_data;
+
+#ifndef TW_NO_LEGACY_PROPS
+	/* Set legacy properties */
+	if (switch_to_legacy_properties() != 0) {
+		LOGERR("Legacy property environment did not initialize successfully. Properties may not be detected.\n");
+	} else {
+		LOGINFO("Legacy property environment initialized.\n");
+	}
+#endif
+
+	pipe(pipe_fd);
+
+	std::vector<std::string> args;
+    if (ztype == UPDATE_BINARY_ZIP_TYPE) {
+		ret_val = update_binary_command(path, Zip, 0, pipe_fd[1], &args);
+    } else if (ztype == AB_OTA_ZIP_TYPE) {
+		ret_val = abupdate_binary_command(path, Zip, 0, pipe_fd[1], &args);
+	} else {
+		LOGERR("Unknown zip type %i\n", ztype);
+		ret_val = INSTALL_CORRUPT;
+	}
+    if (ret_val) {
+        close(pipe_fd[0]);
+        close(pipe_fd[1]);
+        return ret_val;
+    }
+
+	// Convert the vector to a NULL-terminated char* array suitable for execv.
+	const char* chr_args[args.size() + 1];
+	chr_args[args.size()] = NULL;
+	for (size_t i = 0; i < args.size(); i++)
+		chr_args[i] = args[i].c_str();
+
+	pid_t pid = fork();
+	if (pid == 0) {
+		close(pipe_fd[0]);
+		execve(chr_args[0], const_cast<char**>(chr_args), environ);
+		printf("E:Can't execute '%s': %s\n", chr_args[0], strerror(errno));
+		_exit(-1);
+	}
+	close(pipe_fd[1]);
+
+	*wipe_cache = 0;
+
+	DataManager::GetValue(TW_SIGNED_ZIP_VERIFY_VAR, zip_verify);
+	child_data = fdopen(pipe_fd[0], "r");
+	while (fgets(buffer, sizeof(buffer), child_data) != NULL) {
+		char* command = strtok(buffer, " \n");
+		if (command == NULL) {
+			continue;
+		} else if (strcmp(command, "progress") == 0) {
+			char* fraction_char = strtok(NULL, " \n");
+			char* seconds_char = strtok(NULL, " \n");
+
+			float fraction_float = strtof(fraction_char, NULL);
+			int seconds_float = strtol(seconds_char, NULL, 10);
+
+			if (zip_verify)
+				DataManager::ShowProgress(fraction_float * (1 - VERIFICATION_PROGRESS_FRACTION), seconds_float);
+			else
+				DataManager::ShowProgress(fraction_float, seconds_float);
+		} else if (strcmp(command, "set_progress") == 0) {
+			char* fraction_char = strtok(NULL, " \n");
+			float fraction_float = strtof(fraction_char, NULL);
+			DataManager::SetProgress(fraction_float);
+		} else if (strcmp(command, "ui_print") == 0) {
+			char* display_value = strtok(NULL, "\n");
+			if (display_value) {
+				gui_print("%s", display_value);
+			} else {
+				gui_print("\n");
+			}
+		} else if (strcmp(command, "wipe_cache") == 0) {
+			*wipe_cache = 1;
+		} else if (strcmp(command, "clear_display") == 0) {
+			// Do nothing, not supported by TWRP
+		} else if (strcmp(command, "log") == 0) {
+			printf("%s\n", strtok(NULL, "\n"));
+		} else {
+			LOGERR("unknown command [%s]\n", command);
+		}
+	}
+	fclose(child_data);
+
+	int waitrc = TWFunc::Wait_For_Child(pid, &status, "Updater");
+
+#ifndef TW_NO_LEGACY_PROPS
+	/* Unset legacy properties */
+	if (legacy_props_path_modified) {
+		if (switch_to_new_properties() != 0) {
+			LOGERR("Legacy property environment did not disable successfully. Legacy properties may still be in use.\n");
+		} else {
+			LOGINFO("Legacy property environment disabled.\n");
+		}
+	}
+#endif
+
+	if (waitrc != 0)
+		return INSTALL_ERROR;
+
+	return INSTALL_SUCCESS;
+}
+
+extern "C" int TWinstall_zip(const char* path, int* wipe_cache) {
+	int ret_val, zip_verify = 1;
+	ZipArchive Zip;
+
+	if (strcmp(path, "error") == 0) {
+		LOGERR("Failed to get adb sideload file: '%s'\n", path);
+		return INSTALL_CORRUPT;
+	}
+
+	gui_msg(Msg("installing_zip=Installing zip file '{1}'")(path));
+	if (strlen(path) < 9 || strncmp(path, "/sideload", 9) != 0) {
+		string digest_str;
+		string Full_Filename = path;
+		string digest_file = path;
+		digest_file += ".md5";
+
+		gui_msg("check_for_digest=Checking for Digest file...");
+		if (!TWFunc::Path_Exists(digest_file)) {
+			gui_msg("no_digest=Skipping Digest check: no Digest file found");
+		}
+		else {
+			if (TWFunc::read_file(digest_file, digest_str) != 0) {
+				LOGERR("Skipping MD5 check: MD5 file unreadable\n");
+			}
+			else {
+				twrpDigest *digest = new twrpMD5();
+				if (!twrpDigestDriver::stream_file_to_digest(Full_Filename, digest)) {
+					delete digest;
+					return INSTALL_CORRUPT;
+				}
+				string digest_check = digest->return_digest_string();
+				if (digest_str == digest_check) {
+					gui_msg(Msg("digest_matched=Digest matched for '{1}'.")(path));
+				}
+				else {
+					LOGERR("Aborting zip install: Digest verification failed\n");
+					delete digest;
+					return INSTALL_CORRUPT;
+				}
+				delete digest;
+			}
+		}
+	}
+
+#ifndef TW_OEM_BUILD
+	DataManager::GetValue(TW_SIGNED_ZIP_VERIFY_VAR, zip_verify);
+#endif
+	DataManager::SetProgress(0);
+
+	MemMapping map;
+	if (sysMapFile(path, &map) != 0) {
+		gui_msg(Msg(msg::kError, "fail_sysmap=Failed to map file '{1}'")(path));
+		return -1;
+	}
+
+	if (zip_verify) {
+		gui_msg("verify_zip_sig=Verifying zip signature...");
+		std::vector<Certificate> loadedKeys;
+		if (!load_keys("/res/keys", loadedKeys)) {
+			LOGINFO("Failed to load keys");
+			gui_err("verify_zip_fail=Zip signature verification failed!");
+			return -1;
+		}
+		ret_val = verify_file(map.addr, map.length, loadedKeys, NULL);
+		if (ret_val != VERIFY_SUCCESS) {
+			LOGINFO("Zip signature verification failed: %i\n", ret_val);
+			gui_err("verify_zip_fail=Zip signature verification failed!");
+			sysReleaseMap(&map);
+			return -1;
+		} else {
+			gui_msg("verify_zip_done=Zip signature verified successfully.");
+		}
+	}
+	ret_val = mzOpenZipArchive(map.addr, map.length, &Zip);
+	if (ret_val != 0) {
+		gui_err("zip_corrupt=Zip file is corrupt!");
+		sysReleaseMap(&map);
+		return INSTALL_CORRUPT;
+	}
+
+	time_t start, stop;
+	time(&start);
+	const ZipEntry* file_location = mzFindZipEntry(&Zip, ASSUMED_UPDATE_BINARY_NAME);
+	if (file_location != NULL) {
+		LOGINFO("Update binary zip\n");
+		ret_val = Prepare_Update_Binary(path, &Zip, wipe_cache);
+		if (ret_val == INSTALL_SUCCESS)
+			ret_val = Run_Update_Binary(path, &Zip, wipe_cache, UPDATE_BINARY_ZIP_TYPE);
+	} else {
+		file_location = mzFindZipEntry(&Zip, AB_OTA);
+		if (file_location != NULL) {
+			LOGINFO("AB zip\n");
+			ret_val = Run_Update_Binary(path, &Zip, wipe_cache, AB_OTA_ZIP_TYPE);
+		} else {
+			file_location = mzFindZipEntry(&Zip, "ui.xml");
+			if (file_location != NULL) {
+				LOGINFO("TWRP theme zip\n");
+				ret_val = Install_Theme(path, &Zip);
+			} else {
+				mzCloseZipArchive(&Zip);
+				ret_val = INSTALL_CORRUPT;
+			}
+		}
+	}
+	time(&stop);
+	int total_time = (int) difftime(stop, start);
+	if (ret_val == INSTALL_CORRUPT) {
+		gui_err("invalid_zip_format=Invalid zip file format!");
+	} else {
+		LOGINFO("Install took %i second(s).\n", total_time);
+	}
+	sysReleaseMap(&map);
+	return ret_val;
+}