server/rpm_kernel.py

#!/usr/bin/python
#
# Copyright 2007 Google Inc. Released under the GPL v2

"""
This module defines the Kernel class

	Kernel: an os kernel
"""

__author__ = """
mbligh@google.com (Martin J. Bligh),
poirier@google.com (Benjamin Poirier),
stutsman@google.com (Ryan Stutsman)"""


import os, time
from autotest_lib.client.common_lib import error
from autotest_lib.server import kernel, utils


class RPMKernel(kernel.Kernel):
	"""
	This class represents a .rpm pre-built kernel.

	It is used to obtain a built kernel and install it on a Host.

	Implementation details:
	This is a leaf class in an abstract class hierarchy, it must
	implement the unimplemented methods in parent classes.
	"""
	def __init__(self):
		super(RPMKernel, self).__init__()

	def install(self, host, label='autoserv',
		    default=False, kernel_args = '', install_vmlinux=False):
		"""
		Install a kernel on the remote host.
		
		This will also invoke the guest's bootloader to set this
		kernel as the default kernel if default=True.
		
		Args:
			host: the host on which to install the kernel
			[kwargs]: remaining keyword arguments will be passed 
				to Bootloader.add_kernel()
		
		Raises:
			AutoservError: no package has yet been obtained. Call
				RPMKernel.get() with a .rpm package.
		"""
		if len(label) > 15:
			raise error.AutoservError("label for kernel is too long \
			(> 15 chars): %s" % label)
		if self.source_material is None:
			raise error.AutoservError("A kernel must first be \
			specified via get()")
		rpm = self.source_material

		remote_tmpdir = host.get_tmp_dir()	
		remote_rpm = os.path.join(remote_tmpdir, os.path.basename(rpm))
		rpm_package = utils.run('/usr/bin/rpm -q -p %s' % rpm).stdout
		vmlinuz = self.get_image_name()
		host.send_file(rpm, remote_rpm)
		host.run('rpm -e ' + rpm_package, ignore_status = True)
		host.run('rpm --force -i ' + remote_rpm)

		# Copy over the uncompressed image if there is one
                if install_vmlinux:
			vmlinux = self.get_vmlinux_name()
			host.run('cd /;rpm2cpio %s | cpio -imuv .%s'
				% (remote_rpm, vmlinux))
			host.run('ls ' + vmlinux) # Verify

		host.bootloader.remove_kernel(label)
		host.bootloader.add_kernel(vmlinuz, label,
					   args=kernel_args, default=default)
		if kernel_args:
			host.bootloader.add_args(label, kernel_args)
		if not default:
			host.bootloader.boot_once(label)


	def get_version(self):
		"""Get the version of the kernel to be installed.
		
		Returns:
			The version string, as would be returned 
			by 'make kernelrelease'.
		
		Raises:
			AutoservError: no package has yet been obtained. Call
				RPMKernel.get() with a .rpm package.
		"""
		if self.source_material is None:
			raise error.AutoservError("A kernel must first be \
			specified via get()")
		
		retval = utils.run('rpm -qpi %s | grep Version | \
		awk \'{print($3);}\'' % utils.sh_escape(self.source_material))
		return retval.stdout.strip()


	def get_image_name(self):
		"""Get the name of the kernel image to be installed.
		
		Returns:
			The full path to the kernel image file as it will be 
			installed on the host.
		
		Raises:
			AutoservError: no package has yet been obtained. Call
				RPMKernel.get() with a .rpm package.
		"""
		if self.source_material is None:
			raise error.AutoservError("A kernel must first be \
			specified via get()")
		
		vmlinuz = utils.run('rpm -q -l -p %s \
		| grep /boot/vmlinuz' % self.source_material).stdout.strip()
		return vmlinuz


	def get_vmlinux_name(self):
		"""Get the name of the kernel image to be installed.
		
		Returns:
			The full path to the kernel image file as it will be 
			installed on the host. It is the uncompressed and
			unstripped version of the kernel that can be used with
			oprofile.
		
		Raises:
			AutoservError: no package has yet been obtained. Call
				RPMKernel.get() with a .rpm package.
		"""
		if self.source_material is None:
			raise error.AutoservError("A kernel must first be \
			specified via get()")
		
		vmlinux = utils.run('rpm -q -l -p %s \
		| grep /boot/vmlinux' % self.source_material).stdout.strip()
		return vmlinux


	def get_initrd_name(self):
		"""Get the name of the initrd file to be installed.
		
		Returns:
			The full path to the initrd file as it will be 
			installed on the host. If the package includes no 
			initrd file, None is returned
		
		Raises:
			AutoservError: no package has yet been obtained. Call
				RPMKernel.get() with a .rpm package.
		"""
		if self.source_material is None:
			raise error.AutoservError("A kernel must first be \
			specified via get()")

		res = utils.run('rpm -q -l -p %s \
		| grep /boot/initrd' % self.source_material, ignore_status=True)
		if res.exit_status:
			return None
		return res.stdout.strip()