cp: -a now preserves SELinux context, with reduced diagnostics

* copy.c (copy_reg): Reduce SELinux context diagnostics for 'cp -a'.
(copy_internal): Likewise
* copy.h (cp_options): Add boolean reduce_diagnostics.
* cp.c (usage): Say that --archive (-a) behaves like -dR --preserve=all.
(cp_option_init): Initialize added reduce_diagnostics.
(main): Add reduce_diagnostics for the -a option, and preserve SELinux
context, if possible.
* mv.c (cp_options_init): Initialize new cp_options booleans.
* install.c (cp_option_init): Likewise.
* NEWS: Mention those behaviour changes.
* doc/coreutils.texi: Document --preserve=context, document that
diagnostics are not shown for failures of non-mandatory attributes
(just SELinux at the moment).
* tests/cp/cp-a-selinux: Check not only failures, but succesful use
of preserving SELinux context in cp.

1 files changed, 6 insertions, 0 deletions

diff --git a/src/copy.h b/src/copy.h
index 0cdf16be1..8e0b4080e 100644
--- a/src/copy.h
+++ b/src/copy.h
@@ -186,6 +186,12 @@ struct cp_options
      this flag is "true", while with "cp --preserve=all", it is false. */
   bool require_preserve_xattr;
 
+  /* Used as difference boolean between cp -a and cp -dR --preserve=all.
+     If true, non-mandatory failure diagnostics are not displayed. This
+     should prevent poluting cp -a output.
+   */
+  bool reduce_diagnostics;
+
   /* If true, copy directories recursively and copy special files
      as themselves rather than copying their contents. */
   bool recursive;