gistfile1.diff

This is how fstab looks like:
====================================
/boot       emmc    /dev/block/platform/msm_sdcc.1/by-name/boot
/recovery   emmc    /dev/block/platform/msm_sdcc.1/by-name/recovery
/misc       emmc    /dev/block/platform/msm_sdcc.1/by-name/misc
#/system     ext4    /dev/block/platform/msm_sdcc.1/by-name/system
#/data       ext4    /dev/block/platform/msm_sdcc.1/by-name/userdata
#/cache      ext4    /dev/block/platform/msm_sdcc.1/by-name/cache
/sbl1       emmc    /dev/block/platform/msm_sdcc.1/by-name/sbl1
/sbl2       emmc    /dev/block/platform/msm_sdcc.1/by-name/sbl2
/sbl3       emmc    /dev/block/platform/msm_sdcc.1/by-name/sbl3
/tz         emmc    /dev/block/platform/msm_sdcc.1/by-name/tz
/rpm        emmc    /dev/block/platform/msm_sdcc.1/by-name/rpm
/aboot      emmc    /dev/block/platform/msm_sdcc.1/by-name/aboot
/sbl2b      emmc    /dev/block/platform/msm_sdcc.1/by-name/sbl2b
/sbl3b      emmc    /dev/block/platform/msm_sdcc.1/by-name/sbl3b
/tzb        emmc    /dev/block/platform/msm_sdcc.1/by-name/tzb
/rpmb       emmc    /dev/block/platform/msm_sdcc.1/by-name/rpmb
/abootb     emmc    /dev/block/platform/msm_sdcc.1/by-name/abootb
/usb-otg    vfat    /dev/block/sda1     /dev/block/sda  flags=removable;storage;display=USB-OTG

/realdata   ext4    /dev/block/platform/msm_sdcc.1/by-name/userdata
/data       ext4    /realdata/media/0/multirom/roms/test/data flags=bindof=/realdata
/cache      ext4    /realdata/media/0/multirom/roms/test/cache flags=bindof=/realdata
/system     ext4    /realdata/media/0/multirom/roms/test/system flags=bindof=/realdata






diff --git a/partition.cpp b/partition.cpp
index c1c99f6..b9b0acf 100644
--- a/partition.cpp
+++ b/partition.cpp
@@ -475,6 +475,10 @@ bool TWPartition::Process_Flags(string Flags, bool Display_Error) {
 			} else {
 				Use_Userdata_Encryption = false;
 			}
+		} else if (ptr_len > (int)sizeof("bindof=") && strncmp(ptr, "bindof=", sizeof("bindof=")-1) == 0) {
+			ptr += sizeof("bindof=")-1;
+			Bind_Of = ptr;
+			Ignore_Blkid = true;
 		} else {
 			if (Display_Error)
 				LOGERR("Unhandled flag: '%s'\n", ptr);
@@ -818,6 +822,32 @@ bool TWPartition::Mount(bool Display_Error) {
 	Find_Actual_Block_Device();
 
 	// Check the current file system before mounting
+	if(!Bind_Of.empty())
+	{
+		TWPartition *p = PartitionManager.Find_Partition_By_Path(Bind_Of);
+		if(!p)
+		{
+			if(Display_Error)
+				LOGERR("Couldn't find bindof partition %s\n", Bind_Of.c_str());
+			else
+				LOGINFO("Couldn't find bindof partition %s\n", Bind_Of.c_str());
+			return false;
+		}
+
+		if(!p->Mount(Display_Error))
+			return false;
+
+		if(mount(Actual_Block_Device.c_str(), Mount_Point.c_str(), Fstab_File_System.c_str(), MS_BIND, NULL) < 0)
+		{
+			if(Display_Error)
+				LOGERR("Couldn't bind %s to %s\n", Actual_Block_Device.c_str(), Mount_Point.c_str());
+			else
+				LOGINFO("Couldn't bind %s to %s\n", Actual_Block_Device.c_str(), Mount_Point.c_str());
+			return false;
+		}
+		return true;
+	}
+
 	Check_FS_Type();
 	if (Current_File_System == "exfat" && TWFunc::Path_Exists("/sbin/exfat-fuse")) {
 		string cmd = "/sbin/exfat-fuse -o big_writes,max_read=131072,max_write=131072 " + Actual_Block_Device + " " + Mount_Point;
diff --git a/partitionmanager.cpp b/partitionmanager.cpp
index ca93a2a..275a160 100644
--- a/partitionmanager.cpp
+++ b/partitionmanager.cpp
@@ -125,7 +125,10 @@ int TWPartitionManager::Write_Fstab(void) {
 		return false;
 	}
 	for (iter = Partitions.begin(); iter != Partitions.end(); iter++) {
-		if ((*iter)->Can_Be_Mounted) {
+		if (!(*iter)->Bind_Of.empty()) {
+			Line = (*iter)->Actual_Block_Device + " " + (*iter)->Mount_Point + " bind bind\n";
+			fputs(Line.c_str(), fp);
+		} else if ((*iter)->Can_Be_Mounted) {
 			Line = (*iter)->Actual_Block_Device + " " + (*iter)->Mount_Point + " " + (*iter)->Current_File_System + " rw\n";
 			fputs(Line.c_str(), fp);
 		}
@@ -237,6 +240,8 @@ void TWPartitionManager::Output_Partition(TWPartition* Part) {
 		printf("   Format_Block_Size: %i\n", Part->Format_Block_Size);
 	if (!Part->MTD_Name.empty())
 		printf("   MTD_Name: %s\n", Part->MTD_Name.c_str());
+	if (!Part->Bind_Of.empty())
+		printf("   Bind_Of: %s\n", Part->Bind_Of.c_str());
 	string back_meth = Part->Backup_Method_By_Name();
 	printf("   Backup_Method: %s\n\n", back_meth.c_str());
 }
diff --git a/partitions.hpp b/partitions.hpp
index b1af7f8..5e9c2ec 100644
--- a/partitions.hpp
+++ b/partitions.hpp
@@ -154,6 +154,7 @@ private:
 #ifdef TW_INCLUDE_CRYPTO_SAMSUNG
 	string EcryptFS_Password;                                                 // Have to store the encryption password to remount
 #endif
+	string Bind_Of;
 
 friend class TWPartitionManager;
 friend class DataManager;