[LTP] [PATCH v2 1/2] testcase: lib: Create tst_getconf to replace "getconf"

[Cyril Hrubis <chrubis@suse.cz>]

Hi!
> +You may need to retrieve some variable configuration such as PAGESIZE.
> +There is "getconf" application that allows that but as some system may not
> +have it, a "tst_getconf" library allows to retrieve these variables by using
> +"sysconf()" function.

Shouldn't we stress here that we should use the tst_getconf instead of
getconf here?

Something as:

You may need to retrieve configuration values such as PAGESIZE, there is
'getconf' but as some system may not have it, you are advised to use
'tst_getconf' instead. Note that it implements subset of 'getconf'
system variables used by the testcases only.


> +[source,sh]
> +-------------------------------------------------------------------------------
> +# retrieve PAGESIZE
> +pagesize=`tst_getconf PAGESIZE`
> +-------------------------------------------------------------------------------
> +
>  Sleeping for subsecond intervals
>  ++++++++++++++++++++++++++++++++
>  
> diff --git a/testcases/lib/.gitignore b/testcases/lib/.gitignore
> index f36ed99fa..997940006 100644
> --- a/testcases/lib/.gitignore
> +++ b/testcases/lib/.gitignore
> @@ -7,3 +7,4 @@
>  /tst_net_iface_prefix
>  /tst_net_ip_prefix
>  /tst_net_vars
> +/tst_getconf
> \ No newline at end of file
> diff --git a/testcases/lib/Makefile b/testcases/lib/Makefile
> index 398150ae0..77b7b2ef1 100644
> --- a/testcases/lib/Makefile
> +++ b/testcases/lib/Makefile
> @@ -27,6 +27,7 @@ include $(top_srcdir)/include/mk/testcases.mk
>  INSTALL_TARGETS		:= *.sh
>  
>  MAKE_TARGETS		:= tst_sleep tst_random tst_checkpoint tst_rod tst_kvcmp\
> -			   tst_device tst_net_iface_prefix tst_net_ip_prefix tst_net_vars
> +			   tst_device tst_net_iface_prefix tst_net_ip_prefix tst_net_vars\
> +			   tst_getconf
>  
>  include $(top_srcdir)/include/mk/generic_leaf_target.mk
> diff --git a/testcases/lib/tst_getconf.c b/testcases/lib/tst_getconf.c
> new file mode 100644
> index 000000000..7cdef9f54
> --- /dev/null
> +++ b/testcases/lib/tst_getconf.c
> @@ -0,0 +1,66 @@
> +/*
> + * Copyright (c) 2018 Myl??ne Josserand <mylene.josserand@bootlin.com>
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License as
> + * published by the Free Software Foundation; either version 2 of
> + * the License, or (at your option) any later version.
> + *
> + * This program is distributed in the hope that it would be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write the Free Software Foundation,
> + * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
> + */
> +
> +#include <stdio.h>
> +#include <unistd.h>
> +#include <string.h>
> +
> +static void print_help(void)
> +{
> +	printf("Usage: tst_getconf variable\n\n");
> +	printf("       variable: can be PAGESIZE or _NPROCESSORS_ONLN (for the moment)\n");
> +	printf("example: tst_getconf PAGESIZE\n");
> +}
> +
> +int main(int argc, char *argv[])
> +{
> +	int opt;
> +
> +	while ((opt = getopt(argc, argv, ":h")) != -1) {
> +		switch (opt) {
> +		case 'h':
> +			print_help();
> +			return 0;
> +		default:
> +			print_help();
> +			return 1;
> +		}
> +	}
> +
> +	if (argc != 2) {
> +		print_help();
> +		return 1;
> +	}
> +
> +	if (optind >= argc) {
> +		fprintf(stderr, "ERROR: Expected variable argument\n\n");
> +		print_help();
> +		return 1;
> +	}

I doubt that this will ever be true, we do return from main once there
are any options passed, so optind here should be set to 1 and argc == 2
because we checked earlier.

> +	if (!strcmp(argv[optind], "_NPROCESSORS_ONLN"))
> +		printf("%ld", sysconf(_SC_NPROCESSORS_ONLN));
> +	else if (!strcmp(argv[optind],"PAGESIZE"))
> +		printf("%ld", sysconf(_SC_PAGE_SIZE));
> +	else {
> +		printf("Invalid argument");
                                        ^
					Missing newline
> +		return -1;
> +	}

LKML coding style prefers to have curly braces around both (all) blocks
if they are around one of them, hence this should rather be:

if (...) {

} else if (...) {

} else {

}



-- 
Cyril Hrubis
chrubis@suse.cz