[arch-projects] [initscripts] [PATCH] Fix: don't use install where target file can't/shouldn't be removed

[Seblu]

On Mon, Jun 27, 2011 at 11:27 AM, Kurt J. Bosch
<kjb-temp-2009 at alpenjodel.de> wrote:
> Seblu, 2011-06-27 00:51:
>>
>> On Mon, Jun 27, 2011 at 12:44 AM, Kurt J. Bosch
>> <kjb-temp-2009 at alpenjodel.de>  wrote:
>>>
>>> Seblu, 2011-06-27 00:28:
>>>>
>>>> On Sun, Jun 26, 2011 at 11:51 PM, Kurt J. Bosch
>>>> <kjb-temp-2009 at alpenjodel.de>    wrote:
>>>>>
>>>>> ---
>>>>>  functions  |    7 +++++++
>>>>>  rc.sysinit |    4 ++--
>>>>>  2 files changed, 9 insertions(+), 2 deletions(-)
>>>>>
>>>>> diff --git a/functions b/functions
>>>>> index 43414c0..9ad75a9 100644
>>>>> --- a/functions
>>>>> +++ b/functions
>>>>> @@ -428,6 +428,13 @@ install_file() {
>>>>>        install -T "$@"<(printf '%s' "$content") "$file"
>>>>>  }
>>>>>
>>>>> +# install would fail because files can't be removed from /proc
>>>>> +# moreover we don't want to remove nodes from /dev
>>>>> +write_file() {
>>>>> +       local file=$1 content=$2
>>>>> +       printf '%s' "$content">| "$file"
>>>>> +}
>>>>> +
>>>>>  bootlogd_stop() {
>>>>>        [[ -f /run/bootlogd.pid ]] || return 0
>>>>>        touch /var/log/boot
>>>>> diff --git a/rc.sysinit b/rc.sysinit
>>>>> index dcc88f5..2c08f02 100755
>>>>> --- a/rc.sysinit
>>>>> +++ b/rc.sysinit
>>>>> @@ -209,7 +209,7 @@ status "Activating Swap" swapon -a
>>>>>  RANDOM_SEED=/var/lib/misc/random-seed
>>>>>  [[ -f $RANDOM_SEED ]]&&
>>>>>        status "Initializing Random Seed" \
>>>>> -               install_file /dev/urandom "$(<    "$RANDOM_SEED" )"
>>>>> +               cp "$RANDOM_SEED" /dev/urandom
>>>>>
>>>>>  stat_busy "Removing Leftover Files"
>>>>>        rm -rf /etc/{nologin,shutdownpid} /forcefsck /tmp/*
>>>>> /tmp/.*&>/dev/null
>>>>> @@ -225,7 +225,7 @@ stat_done
>>>>>
>>>>>  [[ $HOSTNAME ]]&&
>>>>>        status "Setting Hostname: $HOSTNAME" \
>>>>> -               install_file /proc/sys/kernel/hostname "$HOSTNAME"
>>>>> +               write_file /proc/sys/kernel/hostname "$HOSTNAME"
>>>>>
>>>>
>>>> Do you call a function to do the job of a redirection?
>>>>
>>> Yep. We need to do it _within_ status.
>>
>> Reading (or not) your commit message I thought you wanted to do that.
>> What do you think about doing you eval inside status?
>>
> Would be rather difficult because eval does word splitting.
It was a joke, using eval should be avoided.

>
>> Or better, just rollback from your previous patch where you assert
>> this write can be done in one line with status instead of a classic
>> status_start / status_done?
>> In this case, the use of status is not the best choice I think.
>>
> Using status + write_file is better in this case IMHO for some reasons:
> * It provides DONE/FAIL handling.
Nothing more than calling those 2 lines ?

start_busy "Setting Hostname: $HOSTNAME"
echo $HOSTNAME  > /proc/sys/kernel/hostname && stat_done || stat_fail

or in one line

start_busy "Setting Hostname: $HOSTNAME"; echo $HOSTNAME  >
/proc/sys/kernel/hostname && stat_done || stat_fail


> * We avoid the common pitfall of changing the from stat_busy/stat_done to
> the non working status with redirection later as happened for "Initializing
> Random Seed" two moths ago without beeing fixed until now.
Thos doesn't avoid bad using of status... this just fix a bad status
using by creating a function to write a file.

I see status as an helper for simple cases of stat_*. Here bash syntax
doesn't allow it.

Doesn't forget that initscripts syntax must be easily readable (i tell
this about all your patchs, not only this one)

-- 
Sébastien Luttringer
www.seblu.net