[LTP] [RFC PATCH 1/2] Add support for mixing C and shell code

[Petr Vorel]

Hi Cyril,

> This is a proof of a concept of a seamless C and shell integration. The
> idea is that with this you can mix shell and C code as much as as you
> wish to get the best of the two worlds.

> Signed-off-by: Cyril Hrubis <chrubis@suse.cz>
> ---
>  include/tst_test.h                           | 38 +++++++++++++
>  lib/tst_test.c                               | 51 +++++++++++++++++
>  testcases/lib/.gitignore                     |  1 +
>  testcases/lib/Makefile                       |  4 +-
>  testcases/lib/run_tests.sh                   | 10 ++++
>  testcases/lib/tests/.gitignore               |  6 ++
>  testcases/lib/tests/Makefile                 | 11 ++++
>  testcases/lib/tests/shell_loader.sh          |  5 ++
>  testcases/lib/tests/shell_test01.c           | 17 ++++++
>  testcases/lib/tests/shell_test02.c           | 18 ++++++
>  testcases/lib/tests/shell_test03.c           | 25 +++++++++
>  testcases/lib/tests/shell_test04.c           | 18 ++++++
>  testcases/lib/tests/shell_test05.c           | 27 +++++++++
>  testcases/lib/tests/shell_test06.c           | 16 ++++++
FYI we have shell tests for new library in lib/newlib_tests (C tests) and
lib/newlib_tests/shell/ (shell tests), is it necessary to add new location? Or,
if you prefer this, we should move existing tests from lib/newlib_tests/shell/
to this new location.

Also, we have lib/newlib_tests/runtest.sh script, which runs currently only te
tests which exit 0 (TPASS or TCONF). Here are LTP_SHELL_API_TESTS listed.

Also we have test-shell target in the top level Makefile.

=> these tests (currently only these which exits 0) should be run by test-shell
and thus in CI.

Generally the approach LGTM.

>  	unsigned int needs_hugetlbfs:1;
> @@ -607,6 +612,39 @@ void tst_run_tcases(int argc, char *argv[], struct tst_test *self)
>   */
>  void tst_reinit(void);

> +/**
> + * tst_run_shell() - Prepare the environment and execute a shell script.
> + *
> + * @script_name: A filename of the script.
> + * @params: A NULL terminated array of shell script parameters, pass NULL if
> + *          none are needed. This what is passed starting from argv[1].
> + *
> + * The shell script is executed with LTP_IPC_PATH in environment so that the
> + * binary helpers such as tst_res_ or tst_checkpoint work properly when executed
> + * from the script. This also means that the tst_test.runs_shell flag needs to
> + * be set.
> + *
> + * The shell script itself has to source the tst_env.sh shell script at the
> + * start and after that it's free to use tst_res in the same way C code would
> + * use.
> + *
> + * Example shell script that reports success::
nit: double :

> + *
> + *   #!/bin/sh
> + *   . tst_env.sh
> + *
> + *   tst_res TPASS "Example test works"
> + *
> + * The call returns a pid in a case that you want to examine the return value
> + * of the script yourself. If you do not need to check the return value
> + * yourself you can use tst_reap_children() to wait for the completion. Or let
> + * the test library collect the child automatically, just be wary that the
> + * script and the test both runs concurently at the same time in this case.
> + *
> + * Return: A pid of the shell process.
> + */
> +int tst_run_shell(char *script_name, char *const params[]);
> +
>  unsigned int tst_multiply_timeout(unsigned int timeout);

>  /*
> diff --git a/lib/tst_test.c b/lib/tst_test.c
> index e5bc5bf4d..fa0907353 100644
> --- a/lib/tst_test.c
> +++ b/lib/tst_test.c
> @@ -173,6 +173,52 @@ void tst_reinit(void)
>  	SAFE_CLOSE(fd);
>  }
...

> +int tst_run_shell(char *script_name, char *const params[])
> +{
> +	int pid;
> +	unsigned int i, params_len = params_array_len(params);
> +	char *argv[params_len + 2] = {};
As I noted, this is a problem for old gcc 7 (still used in 15-SP6).

Kind regards,
Petr