How to execute the install-recovery.sh script?

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在`init.rc`文件中添加以下内容以安装recovery并设置其启动：

shellservice flash_recovery /system/etc/install-recovery.shclass mainoneshot

将`/system/etc/install-recovery.sh`路径替换为实际路径。

install-recovery.sh&applypatch

install-recovery.sh & applypatch

android/system/core/rootdir/init.rc：

service flash_recovery /system/etc/install-recovery .sh class main oneshot

out/target/product/xxx/root/init.rc:

service flash_recovery /system/etc/install-recovery .sh class main oneshot

android\bootable\recovery\applypatch

android\build\tools\releasetools\ota_from_target_files

def MakeRecoveryPatch(output_zip, recovery_img, boot_img): """Generate a binary patch that creates the recovery image starting with the boot image. (Most of the space in these images is just the kernel, which is identical for the two, so the resulting patch should be efficient.) Add it to the output zip, along with a shell script that is run from init.rc on first boot to actually do the patching and install the new recovery image. recovery_img and boot_img should be File objects for the corresponding images. info should be the dictionary returned by common.LoadInfoDict() on the input target_files. Returns an Item for the shell script, which must be made executable. """ d = common.Difference(recovery_img, boot_img) _, _, patch = d.ComputePatch() common.ZipWriteStr(output_zip, "recovery/recovery-from-boot.p" , patch) Item.Get( "system/recovery-from-boot.p" , dir = False ) boot_type, boot_device = common.GetTypeAndDevice( "/boot" , OPTIONS.info_dict) recovery_type, recovery_device = common.GetTypeAndDevice( "/recovery" , OPTIONS.info_dict) sh = """#!/system/bin/sh if ! applypatch -c %(recovery_type)s:%(recovery_device)s:%(recovery_size)d:%(recovery_sha1)s; then log -t recovery "Installing new recovery image" applypatch %(boot_type)s:%(boot_device)s:%(boot_size)d:%(boot_sha1)s %(recovery_type)s:%(recovery_device)s %(recovery_sha1)s %(recovery_size)d %(boot_sha1)s:/system/recovery-from-boot.p else log -t recovery "Recovery image already installed" fi """ % { 'boot_size' : boot_img.size, 'boot_sha1' : boot_img.sha1, 'recovery_size' : recovery_img.size, 'recovery_sha1' : recovery_img.sha1, 'boot_type' : boot_type, 'boot_device' : boot_device, 'recovery_type' : recovery_type, 'recovery_device' : recovery_device, } common.ZipWriteStr(output_zip, "recovery/etc/install-recovery.sh" , sh) return Item.Get( "system/etc/install-recovery.sh" , dir = False )

5.ota.zip\recovery\etc\install-recovery.sh:

#!/system/bin/sh if ! applypatch - c MTD:recovery: 3586808 :a1bdc75a0eaa8faf855807c3b60c43dbcfb1400a; then log - t recovery "Installing new recovery image" applypatch MTD:boot: 3776935 : 6cbe8dfacd08ba5cfa39b97e16de0d1f8176c0ed MTD:recovery a1bdc75a0eaa8faf855807c3b60c43dbcfb1400a 3586808 6cbe8dfacd08ba5cfa39b97e16de0d1f8176c0ed : / system / recovery - from - boot.p else log - t recovery "Recovery image already installed" fi

Recoverywillneveroverwriteitself,insteaditwillinstalla/system/etc/install-recovery.shscripttoupdaterecoveryonthenextbootup;thisensuresthatthesystemisalwayscapableofbootingintorecoveryevenifthenormalbootupfails.Theinstall-recovery.shscriptworksbycombiningbootwithapatchandwritingtheresulttotherecoverypartition.