[PATCH v3 0/7] lib/string: Add strscpy_pad() function

From: Tobin C. Harding
Date: Wed Mar 06 2019 - 16:43:18 EST


Hi,

strscpy_pad() patch set now with added test shenanigans.

This version adds 5 initial patches to the set and splits the single
patch from v2 into two separate patches (6 and 7).

While doing the testing for strscpy_pad() it was noticed that there is
duplication in how test modules are being fed to kselftest and also in
the test modules themselves.

This set makes an attempt at adding a framework to kselftest for writing
kernel test modules. It also adds a script for use in creating script
test runners for kselftest. My macro-foo is not great, all criticism
and suggestions very much appreciated. The design is based on test
modules lib/test_printf.c, lib/test_bitmap.c, lib/test_xarray.c.

Shua, I'm by no means a kselftest expert, if this approach does not fit
in with your general direction please say so.

Kees, I put the strscpy_pad() addition patch separate so if this goes in
through Shua's tree (and if it goes in at all) its a single patch to
grab if we want to start playing around with strscpy_pad().


Patch 1 fixes module unload for lib/test_printf in preparation for the
rest of the series.

Patch 2 Adds a shell script that can be used to create shell script test
runners.

Patch 3 Converts current shell script runners in
tools/testing/selftests/lib/ to use the script introduced in
patch 2.

Patch 4 Adds the test framework by way of a header file (inc. documentation)

Patch 5 Converts a couple of current test modules to make some use of
the newly added test framework.

Patch 6 Adds strscpy_pad()

Patch 7 Adds test module for strscpy_pad() using the new framework and script.


If you are a testing geek and you would like to play with this; if you
are already running a kernel built recently from your tree you may
want to just apply the first 5 patches then you don't need to build/boot
a new kernel, just config and build the lib/ test modules (test_printf
etc.) and then:

sudo make TARGETS=lib kselftest

Late in the development of this I found that a bunch of boiler plate had
to be added to the script to handle running tests with:

make O=/path/to/kout kselftest

The reason is that during the build we are in the output directory but
the script is in the source directory. I get the feeling that a better
understanding of how the kernel build process works would provide a
better solution to this. The current solution is disappointing since
removing duplication and boiler plate was the point of the whole
exercise. I'd love a better way to solve this?

One final interesting note: there are 36 test modules in lib/ only 3 of
them are run by kselftest from tools/testing/selfests/lib?


Thanks for looking at this,
Tobin.



Tobin C. Harding (7):
lib/test_printf: Add empty module_exit function
kselftest: Add test runner creation script
kselftest/lib: Use new shell runner to define tests
kselftest: Add test module framework header
lib: Use new kselftest header
lib/string: Add strscpy_pad() function
lib: Add test module for strscpy_pad

Documentation/dev-tools/kselftest.rst | 108 ++++++++++++-
include/linux/string.h | 4 +
lib/Kconfig.debug | 3 +
lib/Makefile | 1 +
lib/string.c | 47 +++++-
lib/test_bitmap.c | 20 +--
lib/test_printf.c | 17 +--
lib/test_strscpy.c | 150 +++++++++++++++++++
tools/testing/selftests/kselftest_module.h | 48 ++++++
tools/testing/selftests/kselftest_module.sh | 75 ++++++++++
tools/testing/selftests/lib/Makefile | 2 +-
tools/testing/selftests/lib/bitmap.sh | 25 ++--
tools/testing/selftests/lib/config | 1 +
tools/testing/selftests/lib/prime_numbers.sh | 23 ++-
tools/testing/selftests/lib/printf.sh | 25 ++--
tools/testing/selftests/lib/strscpy.sh | 17 +++
16 files changed, 490 insertions(+), 76 deletions(-)
create mode 100644 lib/test_strscpy.c
create mode 100644 tools/testing/selftests/kselftest_module.h
create mode 100755 tools/testing/selftests/kselftest_module.sh
create mode 100755 tools/testing/selftests/lib/strscpy.sh

--
2.20.1