V3 test-container: ability to specify exec path

* Fixed Florian's comments from 12 Dec.
* Fixed new_child_name argv[0] bug
* Fixed prog name in usage (was "containerize ...")

From 1904ed5a5a34dafcb8a8a9810317ffc78494a0ab Mon Sep 17 00:00:00 2001
From: DJ Delorie <dj@redhat.com>
Date: Fri, 13 Dec 2019 13:37:30 -0500
Subject: test-container: add exec, cwd

exec <path_to_test_binary> [optional_argv_0]

  copies test binary to specified location and runs it from
  there.  If the second argument is provided, that will
  be used for argv[0]

cwd <directory>

  attempts to chdir(directory) before running test

Note: "cwd" not "cd" as it takes effect just before the
test binary runs, not when it's encountered in the script,
so it can't be used as a path shortcut like "cd" would imply.

cleanup: use xstrdup() instead of strdup()

On 1/28/20 3:38 PM, DJ Delorie wrote:
> 
> * Fixed Florian's comments from 12 Dec.
> * Fixed new_child_name argv[0] bug
> * Fixed prog name in usage (was "containerize ...")

I'm excited to see this go in, I have like 50+ tests I used for
$ORIGIN testing and DST parsing that I can use this for.

The next step would be to also support setuid running inside
the container for testing because many code paths rely on this.

OK for master when it reopens.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>

> From 1904ed5a5a34dafcb8a8a9810317ffc78494a0ab Mon Sep 17 00:00:00 2001
> From: DJ Delorie <dj@redhat.com>
> Date: Fri, 13 Dec 2019 13:37:30 -0500
> Subject: test-container: add exec, cwd
> 
> exec <path_to_test_binary> [optional_argv_0]
> 
>   copies test binary to specified location and runs it from
>   there.  If the second argument is provided, that will
>   be used for argv[0]

OK.

> 
> cwd <directory>
> 
>   attempts to chdir(directory) before running test

OK.

> 
> Note: "cwd" not "cd" as it takes effect just before the
> test binary runs, not when it's encountered in the script,
> so it can't be used as a path shortcut like "cd" would imply.

OK.

> 
> cleanup: use xstrdup() instead of strdup()
> 
> diff --git a/support/test-container.c b/support/test-container.c
> index 4c58254558..e970eb2c18 100644
> --- a/support/test-container.c
> +++ b/support/test-container.c
> @@ -95,6 +95,8 @@ int verbose = 0;
>           mv FILE FILE
>  	 cp FILE FILE
>  	 rm FILE
> +	 cwd PATH
> +	 exec FILE

OK.

>  	 FILE must start with $B/, $S/, $I/, $L/, or /
>  	  (expands to build dir, source dir, install dir, library dir
>  	   (in container), or container's root)
> @@ -104,6 +106,8 @@ int verbose = 0;
>           - 'mv': A minimal move files command.
>           - 'cp': A minimal copy files command.
>           - 'rm': A minimal remove files command.
> +	 - 'cwd': set test working directory
> +	 - 'exec': change test binary location (may end in /)

OK.

>     * mytest.root/postclean.req causes fresh rsync (with delete) after
>       test if present
>  
> @@ -147,7 +151,7 @@ maybe_xmkdir (const char *path, mode_t mode)
>  }
>  
>  /* Temporarily concatenate multiple strings into one.  Allows up to 10
> -   temporary results; use strdup () if you need them to be
> +   temporary results; use xstrdup () if you need them to be

OK.

>     permanent.  */
>  static char *
>  concat (const char *str, ...)
> @@ -670,11 +674,13 @@ main (int argc, char **argv)
>    char *new_objdir_path;
>    char *new_srcdir_path;
>    char **new_child_proc;
> +  char *new_child_exec;

OK.

>    char *command_root;
>    char *command_base;
>    char *command_basename;
>    char *so_base;
>    int do_postclean = 0;
> +  char *change_cwd = NULL;

OK.

>  
>    int pipes[2];
>    char pid_buf[20];
> @@ -701,7 +707,7 @@ main (int argc, char **argv)
>  
>    if (argc < 2)
>      {
> -      fprintf (stderr, "Usage: containerize <program to run> <args...>\n");
> +      fprintf (stderr, "Usage: test-container <program to run> <args...>\n");

OK.

>        exit (1);
>      }
>  
> @@ -746,12 +752,13 @@ main (int argc, char **argv)
>  	}
>      }
>  
> -  pristine_root_path = strdup (concat (support_objdir_root,
> +  pristine_root_path = xstrdup (concat (support_objdir_root,
>  				       "/testroot.pristine", NULL));

OK.

> -  new_root_path = strdup (concat (support_objdir_root,
> +  new_root_path = xstrdup (concat (support_objdir_root,
>  				  "/testroot.root", NULL));

OK.

>    new_cwd_path = get_current_dir_name ();
>    new_child_proc = argv + 1;
> +  new_child_exec = argv[1];

OK.

>  
>    lock_fd = open (concat (pristine_root_path, "/lock.fd", NULL),
>  		 O_CREAT | O_TRUNC | O_RDWR, 0666);
> @@ -778,10 +785,10 @@ main (int argc, char **argv)
>      command_root = concat (support_srcdir_root,
>  			   argv[1] + strlen (support_objdir_root),
>  			   ".root", NULL);
> -  command_root = strdup (command_root);
> +  command_root = xstrdup (command_root);
>  
>    /* This cuts off the ".root" we appended above.  */
> -  command_base = strdup (command_root);
> +  command_base = xstrdup (command_root);
>    command_base[strlen (command_base) - 5] = 0;

OK.

>  
>    /* This is the basename of the test we're running.  */
> @@ -792,7 +799,7 @@ main (int argc, char **argv)
>      ++command_basename;
>  
>    /* Shared object base directory.  */
> -  so_base = strdup (argv[1]);
> +  so_base = xstrdup (argv[1]);

OK.

>    if (strrchr (so_base, '/') != NULL)
>      strrchr (so_base, '/')[1] = 0;
>  
> @@ -806,9 +813,9 @@ main (int argc, char **argv)
>        && S_ISDIR (st.st_mode))
>      rsync (command_root, new_root_path, 0);
>  
> -  new_objdir_path = strdup (concat (new_root_path,
> +  new_objdir_path = xstrdup (concat (new_root_path,
>  				    support_objdir_root, NULL));
> -  new_srcdir_path = strdup (concat (new_root_path,
> +  new_srcdir_path = xstrdup (concat (new_root_path,
>  				    support_srcdir_root, NULL));

OK.

>  
>    /* new_cwd_path starts with '/' so no "/" needed between the two.  */
> @@ -868,7 +875,10 @@ main (int argc, char **argv)
>  		  the_words[i] = concat (new_root_path,
>  					 support_libdir_prefix,
>  					 the_words[i] + 2, NULL);
> -		else if (the_words[i][0] == '/')
> +		/* "exec" and "cwd" use inside-root paths.  */
> +		else if (strcmp (the_words[0], "exec") != 0
> +			 && strcmp (the_words[0], "cwd") != 0
> +			 && the_words[i][0] == '/')
>  		  the_words[i] = concat (new_root_path,
>  					 the_words[i], NULL);

OK.

>  	      }
> @@ -912,13 +922,49 @@ main (int argc, char **argv)
>  	      {
>  		maybe_xunlink (the_words[1]);
>  	      }
> +	    else if (nt >= 2 && strcmp (the_words[0], "exec") == 0)
> +	      {
> +		/* The first argument is the desired location and name
> +		   of the test binary as we wish to exec it; we will
> +		   copy the binary there.  The second (optional)
> +		   argument is the value to pass as argv[0], it
> +		   defaults to the same as the first argument.  */
> +		char *new_exec_path = the_words[1];

OK.

> +
> +		/* If the new exec path ends with a slash, that's the
> +		 * directory, and use the old test base name.  */
> +		if (new_exec_path [strlen(new_exec_path) - 1] == '/')
> +		    new_exec_path = concat (new_exec_path,
> +					    basename (new_child_proc[0]),
> +					    NULL);

OK.

> +
> +
> +		/* new_child_proc is in the build tree, so has the
> +		   same path inside the chroot as outside.  The new
> +		   exec path is, by definition, relative to the
> +		   chroot.  */
> +		copy_one_file (new_child_proc[0],  concat (new_root_path,
> +							   new_exec_path,
> +							   NULL));

OK.

> +
> +		new_child_exec =  xstrdup (new_exec_path);

OK.

> +		if (the_words[2])
> +		  new_child_proc[0] = xstrdup (the_words[2]);
> +		else
> +		  new_child_proc[0] = new_child_exec;

OK. Set new_child_proc[0]

> +	      }
> +	    else if (nt == 2 && strcmp (the_words[0], "cwd") == 0)
> +	      {
> +		change_cwd = xstrdup (the_words[1]);

OK.


> +	      }
>  	    else if (nt == 1 && strcmp (the_words[0], "su") == 0)
>  	      {
>  		be_su = 1;
>  	      }
>  	    else if (nt > 0 && the_words[0][0] != '#')
>  	      {
> -		printf ("\033[31minvalid [%s]\033[0m\n", the_words[0]);
> +		fprintf (stderr, "\033[31minvalid [%s]\033[0m\n", the_words[0]);
> +		exit (1);

OK.

>  	      }
>  	  }
>  	fclose (f);
> @@ -1089,11 +1135,17 @@ main (int argc, char **argv)
>    write (GMAP, tmp, strlen (tmp));
>    xclose (GMAP);
>  
> +  if (change_cwd)
> +    {
> +      if (chdir (change_cwd) < 0)
> +	FAIL_EXIT1 ("Can't cd to %s inside container - ", change_cwd);
> +    }

OK.

> +
>    /* Now run the child.  */
> -  execvp (new_child_proc[0], new_child_proc);
> +  execvp (new_child_exec, new_child_proc);

OK.

>  
>    /* Or don't run the child?  */
> -  FAIL_EXIT1 ("Unable to exec %s\n", new_child_proc[0]);
> +  FAIL_EXIT1 ("Unable to exec %s\n", new_child_exec);

OK.

>  
>    /* Because gcc won't know error () never returns...  */
>    exit (EXIT_UNSUPPORTED);
>