Fork of TWRP

This fork differs from the original in the following ways:

• Designed to be built with LineageOS 14.1 only
• Encrypted backups are disabled by default due to poor implementation, see TWRP Issue #817
• Customize the mksh prompt and environment by editing mksh/mkshrc
• Require fstab v2 syntax (see examples and supported flags below)
• Use external repositories for pigz, exfat, fuse
• SuperSU and HTC Dumlock have been removed
• adb backup is not implemented due to concerns about code quality
• Other minor customizations (see change history)

BusyBox vs. Toybox

This fork is ready to rock with toybox... if only toybox were a truly suitable replacement for busybox. Specify TW_USE_TOYBOX := true to replace busybox with toybox, but be aware that many recovery installable packages depend on tools in busybox like awk that are not present in toybox, as well as arguments to available tools like --ignore-fail-on-non-empty for rmdir and -empty for find that are also missing. So, venture at your own risk.

The BusyBox repository at LineageOS can be synced by adding the following to your local manifest:

<project name="LineageOS/android_external_busybox" path="external/busybox" remote="github" />

At last check (May 4, 2017), LineageOS' busybox repository still needs this patch.

To Do

• Fix hard-coding of alternate block device search (code link)
• Support vold-formatted entries in fstab (e.g. /devices/platform/msm_hsusb_host/usb* instead of /dev/block/sda1)

Versioning

To help distinguish builds of recovery made from this fork, the minor version digit is replaced with M#. Minor version increments will be handled as needed, independent of TWRP. The major and semi-major version digits follow upstream to roughly indicate feature parity (as close as possible with a fork, anyways).

Convention:

• 3.0.M0-0 incorporates all major features from TWRP 3.0.0-0
• 3.0.M1-0 is the minor version increment after 3.0.M0-0 and is independent of any TWRP minor version increment(s)
• 3.1.M0-0 is the semi-major version increment after 3.0.M4-2 and is tied to a TWRP semi-major version increment
• 3.0.M0-1 is a device-specific fix to 3.0.M0-0; this device digit resets when any other version increments

Examples of fstab v2 for TWRP

Example fstab v2 for device mt2:

Worth noting in this example: encryptable= does not need to be specified if encryption keys are stored at the footer of /data. This is the default, assumed location.

# device                                          mount_point     fstype  mount_flags                             fs_mgr_flags   twrp_flags
/dev/block/platform/msm_sdcc.1/by-name/boot       /boot           emmc    defaults                                defaults
/dev/block/platform/msm_sdcc.1/by-name/cache      /cache          ext4    noatime,nosuid,nodev                    defaults
/dev/block/platform/msm_sdcc.1/by-name/userdata   /data           ext4    noatime,nosuid,nodev,noauto_da_alloc    length=-16384
/dev/block/platform/msm_sdcc.1/by-name/modem      /firmware       vfat    ro                                      defaults       twrp=display="Firmware";mounttodecrypt
/dev/block/platform/msm_sdcc.1/by-name/log        /log            ext4    defaults                                defaults       twrp=display="Log"
/dev/block/platform/msm_sdcc.1/by-name/misc       /misc           emmc    defaults                                defaults
/dev/block/platform/msm_sdcc.1/by-name/recovery   /recovery       emmc    defaults                                defaults
/dev/block/platform/msm_sdcc.1/by-name/system     /system         ext4    defaults                                defaults

/dev/block/mmcblk1p1                              /external_sd    vfat    defaults                                defaults       twrp=display="MicroSD";storage;wipeingui;removable
/dev/block/sda1                                   /usb-otg        vfat    defaults                                defaults       twrp=display="USB OTG";storage;wipeingui;removable

Example fstab v2 for device jewel:

# device                                           mount_point     fstype  mount_flags                           fs_mgr_flags                                              twrp_flags
/dev/block/platform/msm_sdcc.1/by-name/boot        /boot           emmc    defaults                              defaults
/dev/block/platform/msm_sdcc.1/by-name/cache       /cache          ext4    noatime,nosuid,nodev                  defaults
/dev/block/platform/msm_sdcc.1/by-name/userdata    /data           ext4    noatime,nosuid,nodev,noauto_da_alloc  encryptable=/dev/block/platform/msm_sdcc.1/by-name/extra
/dev/block/platform/msm_sdcc.1/by-name/devlog      /devlog         ext4    noatime,nosuid,nodev                  defaults                                                  twrp=display="Devlog"
/dev/block/platform/msm_sdcc.1/by-name/misc        /misc           emmc    defaults                              defaults
/dev/block/platform/msm_sdcc.1/by-name/recovery    /recovery       emmc    defaults                              defaults
/dev/block/platform/msm_sdcc.1/by-name/system      /system         ext4    noatime                               defaults

/dev/block/mmcblk1p1                               /external_sd    vfat    defaults                              defaults                                                  twrp=display="MicroSD";storage;wipeingui;removable
/dev/block/sda1                                    /usb-otg        vfat    defaults                              defaults                                                  twrp=display="USB OTG";storage;wipeingui;removable

Supported fstab v2 flags in TWRP

Recognized mount flags (Column 4):
Syntax: comma separated

• bind
• defaults
• noatime
• nodev
• nodiratime
• noexec
• nosuid
• private
• rec
• remount
• ro
• rw
• shared
• slave
• unbindable

Recognized fs_mgr flags (Column 5):
Syntax: comma separated

• defaults
• encryptable=
• length=

Recognized twrp flags (Column 6):
Syntax: semicolon separated, begin with twrp=
Example: twrp=display="Firmware";mounttodecrypt

• andsec
• backup=
• backupname=
• blocksize=
• canbewiped
• canencryptbackup=
• display=
• encryptable=
• flashimg
• forceencrypt=
• ignoreblkid
• length=
• mounttodecrypt
• removable
• retainlayoutversion
• rw
• settingsstorage
• storage
• storagename=
• subpartitionof=
• symlink=
• userdataencryptbackup=
• usermrf
• wipeduringfactoryreset
• wipeingui