Building test applications

This is a description of how to build test applications from a test case.

Dependencies

If you write an application that is supposed to be run on the test-target, place it in the directory ../deps/<name>/ relative to where your test case is placed. The easiest way to obtain the full path to this directory is by calling data_dir.get_deps_dir("<name>"). Don't forget to add from virttest import data_dir to your test case.

Besides the source file, create a Makefile that will be used to build your test application. The below example shows a Makefile for the application for the timedrift test cases. The remote_build module requires that a Makefile is included with all test applications.

.. code-block:: makefile

CFLAGS+=-Wall
LDLIBS+=-lrt

.PHONY: clean

all: clktest get_tsc

clktest: clktest.o

get_tsc: get_tsc.o

clean:
        rm -f clktest get_tsc

remote_build

To simplify the building of applications on target, and to simplify avoiding the building of applications on target when they are installed pre-built, use the remote_build module. This module handles both the transfer of files, and running make on target.

A simple example:

.. code-block:: python

address = vm.get_address(0)
source_dir = data_dir.get_deps_dir("<testapp>")
builder = remote_build.Builder(params, address, source_dir)
full_build_path = builder.build()

In this case, we utilize the .build() method, which execute the necessary methods in builder to copy all files to target and run make (if needed). When done, .build() will return the full path on target to the application that was just built. Be sure to use this path when running your test application, as the path is changed if the parameters of the build is changed. For example:

.. code-block:: python

session.cmd_status("%s --test" % os.path.join(full_build_path, "testapp"))

The remote_build.Builder class can give you fine-grained control over your build process as well. Another way to write the above .build() invocation above is:

.. code-block:: python

builder = remote_build.Builder(params, address, source_dir)
if builder.sync_directories():
    builder.make()
full_build_path = builder.full_build_path

This pattern can be useful if you e.g. would like to add an additional command to run before builder.make(), perhaps to install some extra dependencies.