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GkiDeviceFlashPreparer

public class GkiDeviceFlashPreparer
extends BaseTargetPreparer implements ILabPreparer

java.lang.Object
↳	com.android.tradefed.targetprep.BaseTargetPreparer
	↳	com.android.tradefed.targetprep.GkiDeviceFlashPreparer

A target preparer that flash the device with android common kernel generic image. Please see https://source.android.com/devices/architecture/kernel/android-common for details.

Summary

Public constructors
`GkiDeviceFlashPreparer()`

Public methods
`void`	`setUp(TestInformation testInfo)` Perform the target setup for testing.
`void`	`validateGkiBootImg(ITestDevice device, IBuildInfo buildInfo)` Validate GKI boot image is expected.

Protected methods
`void`	`addHashFooter(ITestDevice device, IBuildInfo buildInfo, File tmpDir)` Validate GKI boot image is expected.
`void`	`buildGkiSystemDlkmImg(ITestDevice device, IBuildInfo buildInfo, File tmpDir)` Build GKI system_dlkm image if the system_dlkm archive is provided.
`File`	`extractSystemDlkmTarGzip(File systemDlkmArchive)` Extracts the system_dlkm tar gzip file into the system_dlkm_staging folder.
`void`	`flattenSystemDlkm(ITestDevice device, File systemDlkmStagingDir)` Flatten the system_dlkm staging directory so that all the kernel modules are directly under /lib/modules.
`String[]`	`getDeviceKernelVersion(ITestDevice device)` Get device kernel version from the device before flashing.
`IHostOptions`	`getHostOptions()` Get a reference to the `IHostOptions`
`String[]`	`getKernelVersionFromImage(File image)` Extracts the kernel version from a boot/vendor_boot/system_dlkm/vendor_dlkm image files.
`File`	`getRequestedFile(ITestDevice device, String requestedFileName, File sourceFile, File tmpDir)` Get the requested file from the source file (zip or folder) by requested file name.
`IRunUtil`	`getRunUtil()` Get the `IRunUtil` instance to use.
`String[]`	`parseKernelVersion(String source, String kernelVersionString)`
`void`	`validateGkiBootImg(ITestDevice device, IBuildInfo buildInfo, File tmpDir)` Validate GKI boot image is expected.
`void`	`validateKernelCompatibility(String imageName, String[] imageVersion, String[] bootVersion, ITestDevice device)`
`void`	`validateKernelVersion(ITestDevice device, IBuildInfo buildInfo, File tmpDir)` Validate kernel versions in the images are expected.

Public constructors

GkiDeviceFlashPreparer

public GkiDeviceFlashPreparer ()

Public methods

setUp

public void setUp (TestInformation testInfo)

Perform the target setup for testing.

Parameters
`testInfo`	`TestInformation`: The `TestInformation` of the invocation.

Throws
`BuildError`
`DeviceNotAvailableException`
`TargetSetupError`

validateGkiBootImg

public void validateGkiBootImg (ITestDevice device, 
                IBuildInfo buildInfo)

Validate GKI boot image is expected. (Obsoleted. Please call with tmpDir provided)

Parameters
`device`	`ITestDevice`: the `ITestDevice`
`buildInfo`	`IBuildInfo`: the `IBuildInfo` the build info

Throws
`TargetSetupError`	if there is no valid gki boot.img

Protected methods

addHashFooter

protected void addHashFooter (ITestDevice device, 
                IBuildInfo buildInfo, 
                File tmpDir)

Validate GKI boot image is expected. Throw exception if there is no valid boot.img.

Parameters
`device`	`ITestDevice`: the `ITestDevice`
`buildInfo`	`IBuildInfo`: the `IBuildInfo` the build info
`tmpDir`	`File`: the temporary directory `File`

Throws
`TargetSetupError`	if there is no valid gki boot.img
`DeviceNotAvailableException`

buildGkiSystemDlkmImg

protected void buildGkiSystemDlkmImg (ITestDevice device, 
                IBuildInfo buildInfo, 
                File tmpDir)

Build GKI system_dlkm image if the system_dlkm archive is provided.

Parameters
`device`	`ITestDevice`: the `ITestDevice`
`buildInfo`	`IBuildInfo`: the `IBuildInfo` the build info
`tmpDir`	`File`: the temporary directory `File`

Throws
`TargetSetupError`	if there is an error building the image file.

extractSystemDlkmTarGzip

protected File extractSystemDlkmTarGzip (File systemDlkmArchive)

Extracts the system_dlkm tar gzip file into the system_dlkm_staging folder. This function is a wrapper around ERROR(/TarUtil.extractTarGzipToTemp) in order to stub out the untarring for unit testing.

Parameters
`systemDlkmArchive`	`File`: the system_dlkm tar gzip file containing GKI modules.

Returns
`File`	File containing the system_dlkm tar gzip contents.

Throws
	java.io.IOException
`IOException`

flattenSystemDlkm

protected void flattenSystemDlkm (ITestDevice device, 
                File systemDlkmStagingDir)

Flatten the system_dlkm staging directory so that all the kernel modules are directly under /lib/modules. This is necessary to match the expected system_dlkm file layout for platform builds.

Parameters
`device`	`ITestDevice`: the `ITestDevice`
`systemDlkmStagingDir`	`File`: the system_dlkm staging directory `File`

Throws
`IOException`	or TargetSetupError if there is an error flattening the system_dlkm.
`TargetSetupError`

getDeviceKernelVersion

protected String[] getDeviceKernelVersion (ITestDevice device)

Get device kernel version from the device before flashing.

Parameters
`device`	`ITestDevice`: The `ITestDevice` to get kernel version from.

Returns
`String[]`	A `ERROR(/String[])` containing the parsed kernel version info: [kernelVersion, patchLevel, pageSize]. Returns null if the version string cannot be parsed.2

Throws
`DeviceNotAvailableException`

getHostOptions

protected IHostOptions getHostOptions ()

Get a reference to the IHostOptions

Returns
`IHostOptions`	the `IHostOptions` to use

getKernelVersionFromImage

protected String[] getKernelVersionFromImage (File image)

Extracts the kernel version from a boot/vendor_boot/system_dlkm/vendor_dlkm image files. This method reads the boot/vendor_boot/system_dlkm/vendor_dlkm image file and searches for a specific pattern in Android kernel version strings. It then parses the found string to extract the kernel version in a standardized format.

Parameters
`image`	`File`: The `File` to the boot image file (e.g., boot.img).

Returns
`String[]`	A `ERROR(/String[])` containing the parsed kernel version info: [kernelVersion, patchLevel, pageSize]. Returns null if the version string cannot be parsed.

getRequestedFile

protected File getRequestedFile (ITestDevice device, 
                String requestedFileName, 
                File sourceFile, 
                File tmpDir)

Get the requested file from the source file (zip or folder) by requested file name.

The provided source file can be a zip file. The method will unzip it to tempary directory and find the requested file by the provided file name.

The provided source file can be a file folder. The method will find the requestd file by the provided file name.

Parameters
`device`	`ITestDevice`: the `ITestDevice`
`requestedFileName`	`String`: the requeste file name String
`sourceFile`	`File`: the source file
`tmpDir`	`File`

Returns
`File`	the file that is specified by the requested file name

Throws
	com.android.tradefed.targetprep.TargetSetupError
`TargetSetupError`

getRunUtil

protected IRunUtil getRunUtil ()

Get the IRunUtil instance to use.

Returns
`IRunUtil`	the `IRunUtil` to use

parseKernelVersion

protected String[] parseKernelVersion (String source, 
                String kernelVersionString)

Parameters
`source`	`String`
`kernelVersionString`	`String`

Returns
`String[]`

validateGkiBootImg

protected void validateGkiBootImg (ITestDevice device, 
                IBuildInfo buildInfo, 
                File tmpDir)

Validate GKI boot image is expected. Throw exception if there is no valid boot.img.

Parameters
`device`	`ITestDevice`: the `ITestDevice`
`buildInfo`	`IBuildInfo`: the `IBuildInfo` the build info
`tmpDir`	`File`: the temporary directory `File`

Throws
`TargetSetupError`	if there is no valid gki boot.img

validateKernelCompatibility

protected void validateKernelCompatibility (String imageName, 
                String[] imageVersion, 
                String[] bootVersion, 
                ITestDevice device)

Parameters
`imageName`	`String`
`imageVersion`	`String`
`bootVersion`	`String`
`device`	`ITestDevice`

Throws
`TargetSetupError`

validateKernelVersion

protected void validateKernelVersion (ITestDevice device, 
                IBuildInfo buildInfo, 
                File tmpDir)

Validate kernel versions in the images are expected. Throw exception if not valid.

Parameters
`device`	`ITestDevice`: the `ITestDevice`
`buildInfo`	`IBuildInfo`: the `IBuildInfo` the build info
`tmpDir`	`File`: the temporary directory `File`

Throws
`TargetSetupError`	if there is no valid gki boot.img
`DeviceNotAvailableException`