Re: [dizzy][PATCH] base-files: Check for /run and /var/lock softlinks on upgrade

[akuster808 <akuster808@gmail.com>]

On 04/14/2015 01:41 PM, Bryan Evenson wrote:
> All,
>
>> -----Original Message-----
>> From: Bryan Evenson
>> Sent: Tuesday, April 14, 2015 11:47 AM
>> To: Bryan Evenson; openembedded-core@lists.openembedded.org
>> Subject: RE: [oe-core][dizzy][PATCH] base-files: Check for /run and /var/lock
>> softlinks on upgrade
>>
>> All,
>>
>>> -----Original Message-----
>>> From: Bryan Evenson [mailto:bevenson@melinkcorp.com]
>>> Sent: Friday, April 10, 2015 12:44 PM
>>> To: openembedded-core@lists.openembedded.org
>>> Cc: Bryan Evenson
>>> Subject: [oe-core][dizzy][PATCH] base-files: Check for /run and
>>> /var/lock softlinks on upgrade
>>>
>>> Commit ea647cd9eebdc3e3121b84074519c4bb305adac9 moved the
>> locations of
>>> /run and /var/lock to match the FHS 3 draft specifications.
>>> However, the install doesn't remove the existing directories.
>>> As a result, upgrading a system may result in /run as a softlink to
>>> /var/run and /var/run as a softlink to /run, creating a circular link.
>>>
>>> During pre and post-install, check for the existence of the old
>>> softlinks, move the old file contents to a temporary location, remove
>>> the softlinks, and restore the directory contents after installation.
>>>
>>
>> I went about this wrong, as I forgot that items may be mounted under /run.
>> I'm working on a different solution in which the preinst step removes the
>> /run and /var/lock softlinks if they exist.  However, I still have odd issues.
>> The first reboot works fine, but then on the next reboot there is a link inside
>> /run for "run -> /var/run" and inside /var there is a link for "run ->
>> /var/volatile/run".  This doesn't match up with the files listed in the base-files
>> recipe.  I can't figure out where these links are coming from.  Has anyone else
>> had issues upgrading base-files?
>
> The root cause seems to be the initscripts package.  The script /etc/volatile.cache is generated by /etc/init.d/populate-volatile.sh.  On upgrade, this file is not removed and may not necessarily be regenerated.  As a result, on the next boot the script /etc/volatile.cache repopulates directories as it remembers them which may not be accurate.  In my case, after the reboot, the /etc/volatile.cache script deleted everything from a USB flash drive attached to my system when it attempted to remove /run.
>
> So to get this portion of the upgrade to work, I had to:
> 1. Remove the softlinks for /run and /var/lock through a preinst script in the base-files recipe
> 2. Remove /etc/volatile.cache as a postint script in the initscripts recipe
>
> Would someone like for me to submit a patch?

sure.

- armin
>
> Thanks,
> Bryan
>
>>
>> Thanks,
>> Bryan
>>
>>> Signed-off-by: Bryan Evenson <bevenson@melinkcorp.com>
>>> ---
>>>   meta/recipes-core/base-files/base-files_3.0.14.bb | 55
>>> +++++++++++++++++++++++
>>>   1 file changed, 55 insertions(+)
>>>
>>> diff --git a/meta/recipes-core/base-files/base-files_3.0.14.bb
>>> b/meta/recipes-core/base-files/base-files_3.0.14.bb
>>> index 07f5c54..71cea08 100644
>>> --- a/meta/recipes-core/base-files/base-files_3.0.14.bb
>>> +++ b/meta/recipes-core/base-files/base-files_3.0.14.bb
>>> @@ -66,6 +66,41 @@ hostname = "openembedded"
>>>
>>>   BASEFILESISSUEINSTALL ?= "do_install_basefilesissue"
>>>
>>> +# In previous versions of base-files, /run was a softlink to /var/run
>>> +and the # directory was located in /var/volatlie/run.  Also,
>>> +/var/lock was a softlink # to /var/volatile/lock which is where the
>>> +real directory was located.  Now, # /run and /run/lock are the real
>>> +directories.  If we are upgrading, we may # need to remove the symbolic
>> links first before we create the directories.
>>> +# Otherwise the directory creation will fail and we will have
>>> +circular symbolic # links.
>>> +#
>>> +# If we do need to remove the symbolic links first, we also need to
>>> +preserve # all the contents of the directory so running programs can
>>> +find the files that # are in use in these directories.  Move the
>>> +contents to a temporary
>>> directory
>>> +# during pre-install to protect the contents pkg_preinst_${PN} () {
>>> +    #!/bin/sh -e
>>> +    if [ x"$D" = "x" ]; then
>>> +        if [ -e "/var/volatile/lock" ]; then
>>> +            # Move the contents of /var/volatile/lock to a temporary directory
>>> +            mkdir -p /run_lock_tmp
>>> +            mv /var/volatile/lock/* /run_lock_tmp/
>>> +
>>> +            # Remove the current directory
>>> +            rm -rf /var/volatile/lock
>>> +        fi
>>> +
>>> +        if [ -h "/run" ]; then
>>> +            # Move the contents of /run to a temporary directory
>>> +            mkdir -p /run_tmp
>>> +            mv /run/* /run_tmp/
>>> +
>>> +            # Remove the current directory
>>> +            rm -rf /run
>>> +        fi
>>> +    fi
>>> +}
>>> +
>>>   do_install () {
>>>   	for d in ${dirs755}; do
>>>   		install -m 0755 -d ${D}$d
>>> @@ -79,6 +114,7 @@ do_install () {
>>>   	for d in ${volatiles}; do
>>>   		ln -sf volatile/$d ${D}${localstatedir}/$d
>>>   	done
>>> +
>>>   	ln -snf ../run ${D}${localstatedir}/run
>>>   	ln -snf ../run/lock ${D}${localstatedir}/lock
>>>
>>> @@ -144,6 +180,25 @@ do_install_append_linuxstdbase() {
>>>           done
>>>   }
>>>
>>> +# If we are on the actual hardware, check if we had to move /run and
>>> /run/lock.
>>> +# If so, copy the temporary directory contents to their new locations.
>>> +pkg_postinst_${PN} () {
>>> +    #!/bin/sh -e
>>> +    if [ x"$D" = "x" ]; then
>>> +        if [ -e "/run_tmp" ]; then
>>> +            mv /run_tmp/* /run/
>>> +            rmdir /run_tmp
>>> +        fi
>>> +
>>> +        if [ -e "/run_lock_tmp/" ]; then
>>> +            mv /run_lock_tmp/* /run/lock
>>> +            rmdir /run_lock_tmp
>>> +        fi
>>> +    else
>>> +        exit 1
>>> +    fi
>>> +}
>>> +
>>>   PACKAGES = "${PN}-doc ${PN} ${PN}-dev ${PN}-dbg"
>>>   FILES_${PN} = "/"
>>>   FILES_${PN}-doc = "${docdir} ${datadir}/common-licenses"
>>> --
>>> 2.1.0
>