On 08/27/2017 09:23 AM, Colin Watson wrote:
> From 0a74257b9fb7e02587b6c5553d8bc1b536249a7e Mon Sep 17 00:00:00 2001
> From: Colin Watson <cjwat...@debian.org>
> Date: Sun, 27 Aug 2017 08:16:21 +0100
> Subject: [PATCH] env: add --chdir option
>
> This is useful when chaining with other commands that run commands in a
> different context.
>
> * NEWS (New features): Document the new option.
> * doc/coreutils.texi (env invocation): Likewise.
> * src/env.c (usage): Likewise.
> (main): Implement the new option.
> * tests/misc/env.sh: Test the new option.
> ---
> NEWS | 3 +++
> doc/coreutils.texi | 17 +++++++++++++++++
> src/env.c | 20 ++++++++++++++++++++
> tests/misc/env.sh | 10 +++++++++-
> 4 files changed, 49 insertions(+), 1 deletion(-)
>
> diff --git a/NEWS b/NEWS
> index d37195e..60d5ca5 100644
> --- a/NEWS
> +++ b/NEWS
> @@ -86,6 +86,9 @@ GNU coreutils NEWS -*-
> outline -*-
>
> expr supports multibyte strings for all string operations.
>
> + env now has a --chdir option to change to a new working directory before
> + executing the subsidiary program.
> +
To me (as non-native), "new working directory" might sound like the
directory may be created at the same time, doesn't it?
Maybe
s/to change to a new working directory/to change the working directory/
?
> ** Improvements
>
> mv --verbose now distinguishes rename and copy operations.
> diff --git a/doc/coreutils.texi b/doc/coreutils.texi
> index 8f1cb4c..f127517 100644
> --- a/doc/coreutils.texi
> +++ b/doc/coreutils.texi
> @@ -16909,6 +16909,23 @@ environment.
> @opindex --ignore-environment
> Start with an empty environment, ignoring the inherited environment.
>
> +@item --chdir=@var{dir}
> +@opindex --chdir
> +Change the working directory to @var{dir} before invoking @var{command}.
> +This differs from the shell built-in @command{cd} in that it starts
> +@var{command} as a subprocess rather than altering the shell's own working
> +directory; this allows it to be chained with other commands that run commands
> +in a different context. For example:
> +
> +@example
> +# Run 'true' with /chroot as its root directory and /srv as its working
> +# directory.
> +chroot /chroot env --chdir=/srv true
> +# Run 'true' with /build as its working directory, FOO=bar in its
> +# environment, and a time limit of five seconds.
> +env --chdir=/build FOO=bar timeout 5 true
> +@end example
> +
> @end table
>
> @cindex exit status of @command{env}
> diff --git a/src/env.c b/src/env.c
> index 63d5c2c..291fbb4 100644
> --- a/src/env.c
> +++ b/src/env.c
> @@ -33,11 +33,19 @@
> proper_name ("Richard Mlynarik"), \
> proper_name ("David MacKenzie")
>
> +/* For long options that have no equivalent short option, use a
> + non-character as a pseudo short option, starting with CHAR_MAX + 1. */
> +enum
> +{
> + CHDIR = CHAR_MAX + 1
> +};
> +
> static struct option const longopts[] =
> {
> {"ignore-environment", no_argument, NULL, 'i'},
> {"null", no_argument, NULL, '0'},
> {"unset", required_argument, NULL, 'u'},
> + {"chdir", required_argument, NULL, CHDIR},
> {GETOPT_HELP_OPTION_DECL},
> {GETOPT_VERSION_OPTION_DECL},
> {NULL, 0, NULL, 0}
> @@ -63,6 +71,7 @@ Set each NAME to VALUE in the environment and run
> COMMAND.\n\
> -i, --ignore-environment start with an empty environment\n\
> -0, --null end each output line with NUL, not newline\n\
> -u, --unset=NAME remove variable from the environment\n\
> + --chdir=DIR change working directory to DIR\n\
> "), stdout);
> fputs (HELP_OPTION_DESCRIPTION, stdout);
> fputs (VERSION_OPTION_DESCRIPTION, stdout);
> @@ -81,6 +90,7 @@ main (int argc, char **argv)
> int optc;
> bool ignore_environment = false;
> bool opt_nul_terminate_output = false;
> + char const *newdir = NULL;
>
> initialize_main (&argc, &argv);
> set_program_name (argv[0]);
> @@ -103,6 +113,9 @@ main (int argc, char **argv)
> case '0':
> opt_nul_terminate_output = true;
> break;
> + case CHDIR:
> + newdir = optarg;
> + break;
Please use tab-free indentation as throughout the whole coreutils
sources.
> case_GETOPT_HELP_CHAR;
> case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
> default:
> @@ -154,6 +167,13 @@ main (int argc, char **argv)
> usage (EXIT_CANCELED);
> }
>
> + if (newdir)
> + {
> + if (chdir (newdir) != 0)
> + die (EXIT_CANCELED, errno, _("cannot change directory to %s"),
> + quoteaf (newdir));
> + }
> +
Likewise.
> execvp (argv[optind], &argv[optind]);
>
> int exit_status = errno == ENOENT ? EXIT_ENOENT : EXIT_CANNOT_INVOKE;
> diff --git a/tests/misc/env.sh b/tests/misc/env.sh
> index f2f6ba8..c409630 100755
> --- a/tests/misc/env.sh
> +++ b/tests/misc/env.sh
> @@ -18,7 +18,7 @@
>
>
> . "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
> -print_ver_ env
> +print_ver_ env pwd
>
> # A simple shebang program to call "echo" from symlinks like "./-u" or
> "./--".
> echo "#!$abs_top_builddir/src/echo simple_echo" > simple_echo \
> @@ -150,4 +150,12 @@ test "x$(sh -c '\c=d echo fail')" = xpass && #dash 0.5.4
> fails so check first
> returns_ 125 env -u a=b true || fail=1
> returns_ 125 env -u '' true || fail=1
>
> +# Verify changing directory.
> +mkdir empty || framework_failure_
> +returns_ 125 env --chdir=empty/nonexistent true || fail=1
> +curdir=$(env pwd) || fail=1
> +test "$curdir" = "$(pwd)" || fail=1
The above does not run CU's version of pwd, but instead
that of the shell. The test therefore fails when "pwd -L"
!= "pwd -P" (and the implementation of coreutils and that
of the shell differs).
> +curdir=$(env --chdir=empty pwd) || fail=1
> +test "$curdir" = "$(cd empty && pwd)" || fail=1
> +
> Exit $fail
> --
I therefore propose to squash in the following change:
diff --git a/tests/misc/env.sh b/tests/misc/env.sh
index c409630..7c864cd 100755
--- a/tests/misc/env.sh
+++ b/tests/misc/env.sh
@@ -153,9 +153,8 @@ returns_ 125 env -u '' true || fail=1
# Verify changing directory.
mkdir empty || framework_failure_
returns_ 125 env --chdir=empty/nonexistent true || fail=1
-curdir=$(env pwd) || fail=1
-test "$curdir" = "$(pwd)" || fail=1
-curdir=$(env --chdir=empty pwd) || fail=1
-test "$curdir" = "$(cd empty && pwd)" || fail=1
+exp=$(cd empty && env pwd) || framework_failure_
+got=$(env --chdir=empty pwd) || fail=1
Thanks & have a nice day,
Berny
