qtest.rst (2847B)
1 ======================================== 2 QTest Device Emulation Testing Framework 3 ======================================== 4 5 .. toctree:: 6 7 qgraph 8 9 QTest is a device emulation testing framework. It can be very useful to test 10 device models; it could also control certain aspects of QEMU (such as virtual 11 clock stepping), with a special purpose "qtest" protocol. Refer to 12 :ref:`qtest-protocol` for more details of the protocol. 13 14 QTest cases can be executed with 15 16 .. code:: 17 18 make check-qtest 19 20 The QTest library is implemented by ``tests/qtest/libqtest.c`` and the API is 21 defined in ``tests/qtest/libqtest.h``. 22 23 Consider adding a new QTest case when you are introducing a new virtual 24 hardware, or extending one if you are adding functionalities to an existing 25 virtual device. 26 27 On top of libqtest, a higher level library, ``libqos``, was created to 28 encapsulate common tasks of device drivers, such as memory management and 29 communicating with system buses or devices. Many virtual device tests use 30 libqos instead of directly calling into libqtest. 31 Libqos also offers the Qgraph API to increase each test coverage and 32 automate QEMU command line arguments and devices setup. 33 Refer to :ref:`qgraph` for Qgraph explanation and API. 34 35 Steps to add a new QTest case are: 36 37 1. Create a new source file for the test. (More than one file can be added as 38 necessary.) For example, ``tests/qtest/foo-test.c``. 39 40 2. Write the test code with the glib and libqtest/libqos API. See also existing 41 tests and the library headers for reference. 42 43 3. Register the new test in ``tests/qtest/meson.build``. Add the test 44 executable name to an appropriate ``qtests_*`` variable. There is 45 one variable per architecture, plus ``qtests_generic`` for tests 46 that can be run for all architectures. For example:: 47 48 qtests_generic = [ 49 ... 50 'foo-test', 51 ... 52 ] 53 54 4. If the test has more than one source file or needs to be linked with any 55 dependency other than ``qemuutil`` and ``qos``, list them in the ``qtests`` 56 dictionary. For example a test that needs to use the ``QIO`` library 57 will have an entry like:: 58 59 { 60 ... 61 'foo-test': [io], 62 ... 63 } 64 65 Debugging a QTest failure is slightly harder than the unit test because the 66 tests look up QEMU program names in the environment variables, such as 67 ``QTEST_QEMU_BINARY`` and ``QTEST_QEMU_IMG``, and also because it is not easy 68 to attach gdb to the QEMU process spawned from the test. But manual invoking 69 and using gdb on the test is still simple to do: find out the actual command 70 from the output of 71 72 .. code:: 73 74 make check-qtest V=1 75 76 which you can run manually. 77 78 79 .. _qtest-protocol: 80 81 QTest Protocol 82 -------------- 83 84 .. kernel-doc:: softmmu/qtest.c 85 :doc: QTest Protocol 86 87 88 libqtest API reference 89 ---------------------- 90 91 .. kernel-doc:: tests/qtest/libqtest.h