I had another look and I see another report querying
why the group for new files is set to that of the dir,
rather than that of the current user:
http://unix.stackexchange.com/q/63865/37127
I'll apply the two attached patches to avoid the issue,
and also document the related install -C caveats in this area.
thanks,
Pádraig.
>From 789cc67641feb6d214e717d26c22935c33d6bd2a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?P=C3=A1draig=20Brady?= <p...@draigbrady.com>
Date: Fri, 12 Apr 2013 22:57:45 +0100
Subject: [PATCH] tests: avoid false failures with non default groups
On OS X it was seen that the group ID used for new files,
are set to a that of the directory rather than the current user.
It's not currently understood when this happens, but it was confirmed
that ACLs, extended attributes and setgid bits are _not_ involved.
* init.cfg (skip_if_nondefault_group_): A new function to detect
and avoid this situation. Document with links to the discussions
for hopefully future clarification.
* tests/install/install-C-root.sh: Use the new function.
* tests/install/install-C-selinux.sh: Likewise.
* tests/install/install-C.sh: Likewise.
---
init.cfg | 13 +++++++++++++
tests/install/install-C-root.sh | 1 +
tests/install/install-C-selinux.sh | 2 +-
tests/install/install-C.sh | 25 +++++++++++++++++++++++++
4 files changed, 40 insertions(+), 1 deletions(-)
diff --git a/init.cfg b/init.cfg
index 093cd85..7976b61 100644
--- a/init.cfg
+++ b/init.cfg
@@ -502,6 +502,19 @@ skip_if_setgid_()
esac
}
+# Skip if files are created with a different group to the current user
+# This can happen due to a setgid dir, or by some other mechanism on OS X:
+# http://unix.stackexchange.com/q/63865
+# http://bugs.gnu.org/14024#41
+skip_if_nondefault_group_()
+{
+ touch grp.$$
+ gen_ug=$(stat -c '%u:%g' grp.$$)
+ rm grp.$$
+ test "$gen_ug" = "$(id -ru):$(id -rg)" ||
+ skip_ 'Files are created with a different gid'
+}
+
skip_if_mcstransd_is_running_()
{
test $# = 0 || framework_failure_
diff --git a/tests/install/install-C-root.sh b/tests/install/install-C-root.sh
index d8a8d84..6e6d7eb 100755
--- a/tests/install/install-C-root.sh
+++ b/tests/install/install-C-root.sh
@@ -20,6 +20,7 @@
print_ver_ ginstall
require_root_
skip_if_setgid_
+skip_if_nondefault_group_
u1=1
u2=2
diff --git a/tests/install/install-C-selinux.sh b/tests/install/install-C-selinux.sh
index 8513d50..ce9e0c3 100755
--- a/tests/install/install-C-selinux.sh
+++ b/tests/install/install-C-selinux.sh
@@ -19,7 +19,7 @@
. "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
print_ver_ ginstall
require_selinux_
-
+skip_if_nondefault_group_
echo test > a || framework_failure_
chcon -u system_u a || skip_ "chcon doesn't work"
diff --git a/tests/install/install-C.sh b/tests/install/install-C.sh
index 7d3582c..6051d57 100755
--- a/tests/install/install-C.sh
+++ b/tests/install/install-C.sh
@@ -19,6 +19,31 @@
. "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
print_ver_ ginstall
skip_if_setgid_
+skip_if_nondefault_group_
+
+# Note if a group is not specified, install(1) will assume that a file
+# would be installed with the current user's group ID, and thus if the
+# file is the same except that it does have a different group due to
+# its parent directory being g+s for example, then the copy will be
+# done again redundantly in a futile attempt to reset the group ID to
+# that of the current user.
+#
+# install -d -g wheel -m 2775 test # Create setgid dir
+# touch test/a # Create source
+# install -Cv -m664 test/a test/i1 # install source with mode
+# install -Cv -m664 test/i1 test/i2 # install dest
+# install -Cv -m664 test/i1 test/i2 # again to see redundant install
+#
+# Similarly if an existing file exists that is the same and has the
+# current users group ID, but when an actual install of the file would
+# reset to a different group ID due to the directory being g+s for example,
+# then the install will not be done when it should.
+#
+# install -Cv -m664 -g "$(id -nrg)" test/i1 test/i2 # set i2 to uesr's gid
+# install -Cv -m664 test/i1 test/i2 # this should install but doesn't
+#
+# Therefore we skip the test in the presence of setgid dirs
+# An additional complication on HFS is that it...
mode1=0644
mode2=0755
--
1.7.7.6
>From 719dd5ba8bd88b86fd630fea127251ea40a4471f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?P=C3=A1draig=20Brady?= <p...@draigbrady.com>
Date: Sat, 13 Apr 2013 22:23:01 +0100
Subject: [PATCH] doc: mention caveats with using install --compare
* doc/coreutils.texi (install invocation): Mention that install(1) may
not correctly determine the default user or permissions for installed
files, and so is best used with options specifying these attributes.
---
doc/coreutils.texi | 6 ++++++
1 files changed, 6 insertions(+), 0 deletions(-)
diff --git a/doc/coreutils.texi b/doc/coreutils.texi
index 4cfe4c5..d9e93ae 100644
--- a/doc/coreutils.texi
+++ b/doc/coreutils.texi
@@ -8895,6 +8895,12 @@ The program accepts the following options. Also see @ref{Common options}.
Compare each pair of source and destination files, and if the destination has
identical content and any specified owner, group, permissions, and possibly
SELinux context, then do not modify the destination at all.
+Note this option is best used in conjunction with @option{--user},
+@option{--group} and @option{--mode} options, lest @command{install}
+incorrectly determines the default attributes that installed files would have
+(as it doesn't consider setgid directories and POSIX default ACLs for example).
+This could result in redundant copies or attributes that are not reset to the
+correct defaults.
@item -c
@opindex -c
--
1.7.7.6
