[LTP] [PATCH] newlib_tests/test_exec.c: Fix compiler error before glibc v2.11

[Cyril Hrubis <chrubis@suse.cz>]

Hi!
> Before glibc v2.11, execvpe() was not introduced and resulted in
> compiler error, so we replace execvpe() with execve() and update
> test-writing-guidelines.txt.
> 
> Signed-off-by: xiao yang <yangx.jy@cn.fujitsu.com>
> ---
>  doc/test-writing-guidelines.txt | 11 ++++++++---
>  lib/newlib_tests/test_exec.c    | 11 ++++++++---
>  2 files changed, 16 insertions(+), 6 deletions(-)
> 
> diff --git a/doc/test-writing-guidelines.txt b/doc/test-writing-guidelines.txt
> index a169724..f62e16e 100644
> --- a/doc/test-writing-guidelines.txt
> +++ b/doc/test-writing-guidelines.txt
> @@ -696,15 +696,20 @@ a non zero exit code.
>  [source,c]
>  -------------------------------------------------------------------------------
>  /* test.c */
> -#define _GNU_SOURCE
> -#include <stdlib.h>
> +#include <unistd.h>
>  #include "tst_test.h"
>  
> +extern char **environ;

Looking at this the only change here should be:

> -#include <stdlib.h>
> +#include <unistd.h>

As man 7 environ says:

(This variable must be declared in the user program, but is declared in
the header file <unistd.h> if the _GNU_SOURCE feature test macro is
defined.)

Or is environ not defined with _GNU_SOURCE for older libc?

>  static void do_test(void)
>  {
>  	char *const argv[] = {"test_exec_child", NULL};
> +	char path[4096];
> +
> +	if (tst_get_path("test_exec_child", path, sizeof(path)))
> +		tst_brk(TCONF, "Couldn't find test_exec_child in $PATH");
>  
> -	execvpe(argv[0], argv, environ);
> +	execve(path, argv, environ);
>  	tst_res(TBROK | TERRNO, "EXEC!");
>  }
> diff --git a/lib/newlib_tests/test_exec.c b/lib/newlib_tests/test_exec.c
> index 8aef621..e70080e 100644
> --- a/lib/newlib_tests/test_exec.c
> +++ b/lib/newlib_tests/test_exec.c
> @@ -24,15 +24,20 @@
>   * $ PATH=$PATH:$PWD ./test_exec
>   */
>  
> -#define _GNU_SOURCE
> -#include <stdlib.h>
> +#include <unistd.h>
>  #include "tst_test.h"
>  
> +extern char **environ;

Here as well.

>  static void do_test(void)
>  {
>  	char *const argv[] = {"test_exec_child", NULL};
> +	char path[4096];
> +
> +	if (tst_get_path("test_exec_child", path, sizeof(path)))
> +		tst_brk(TCONF, "Couldn't find test_exec_child in $PATH");
>  
> -	execvpe(argv[0], argv, environ);
> +	execve(path, argv, environ);
>  
>  	tst_res(TBROK | TERRNO, "EXEC!");
>  }

Otherwise it looks good.

-- 
Cyril Hrubis
chrubis@suse.cz