LinuxQuestions.org - a patch to script 'init' which in mkinitrd-1.4.6-i486-5

- Slackware (https://www.linuxquestions.org/questions/slackware-14/)

- - a patch to script 'init' which in mkinitrd-1.4.6-i486-5 - slackware-current (https://www.linuxquestions.org/questions/slackware-14/a-patch-to-script-init-which-in-mkinitrd-1-4-6-i486-5-slackware-current-868813/)

a patch to script 'init' which in mkinitrd-1.4.6-i486-5 - slackware-current

Make the code work when RESUMEDEV is a symbolic link which has a relative path.

Code:

diff -Naur initrd-tree-orig/init initrd-tree-new/init

--- initrd-tree-orig/init        2011-03-13 23:41:35.000000000 +0000

+++ initrd-tree-new/init        2011-03-16 02:03:42.990812427 +0000

@@ -260,12 +260,16 @@

  

  # Resume state from swap

  if [ "$RESUMEDEV" != "" ]; then

+    OLDCWD="$(pwd)"

    if ls -l $RESUMEDEV | grep -q "^l" ; then

+      cd "$(dirname "$RESUMEDEV")"

      RESUMEDEV=$(ls -l $RESUMEDEV | awk '{ print $NF }')

    fi

    echo "Trying to resume from $RESUMEDEV"

    RESMAJMIN=$(ls -l $RESUMEDEV | tr , : | awk '{ print $5$6 }')

    echo $RESMAJMIN > /sys/power/resume

+    cd "$OLDCWD"

+    unset OLDCWD

  fi

  

  # Switch to real root partition:

Submit your patch to Alien Bob for consideration.

Quote:

Originally Posted by Bruce Hill (Post 4292436)

Submit your patch to Alien Bob for consideration.

I don't know who maintain the script before now.
I'll do it later.
thanks.
;)

I think it's AlienBOB
You can find his contact from his blog: http://alien.slackbook.org/blog/

Quote:

Originally Posted by willysr (Post 4293198)

I think it's AlienBOB
You can find his contact from his blog: http://alien.slackbook.org/blog/

Alien Bob

Or go straight to the top:
volkerdi

willy, on LQ we'd post the LQ username.

hello.freeman,

Pat Volkerding's email is posted in many Slackware files.

edit: deleted the last one as I think you can simplify further. (no need for all the readlink stuff)

Code:

printf '%d:%d\n' $(stat -L -c '0x%t 0x%T' $RESUMEDEV) >/sys/power/resume

looks like it ought to do the job.

I fail to see precisely how this changes anything at all. For example:

Code:

alan@darkstar:~$ cd /home/alan

alan@darkstar:~$ mkdir /home/alan/bar

alan@darkstar:~$ ln -s /dev/../dev/../dev/sda2 /home/alan/foo

alan@darkstar:~$ ls -l foo

lrwxrwxrwx 1 alan users 23 Mar 17 09:41 foo -> /dev/../dev/../dev/sda2

export RESUMEDEV=/home/alan/foo

Now let's see what happens when running the current init.

Code:

alan@darkstar:~$    if [ "$RESUMEDEV" != "" ]; then

>      OLDCWD="$(pwd)"

>      if ls -l $RESUMEDEV | grep -q "^l" ; then

>        #cd "$(dirname "$RESUMEDEV")"

>        RESUMEDEV=$(ls -l $RESUMEDEV | awk '{ print $NF }')

>      fi

>      echo "Trying to resume from $RESUMEDEV"

>      RESMAJMIN=$(ls -l $RESUMEDEV | tr , : | awk '{ print $5$6 }')

>      echo $RESMAJMIN

>    fi

Trying to resume from /dev/../dev/../dev/sda2

8:2

Now let's look at it with your patch.

Code:

alan@darkstar:~$      if [ "$RESUMEDEV" != "" ]; then

>        OLDCWD="$(pwd)"

>        if ls -l $RESUMEDEV | grep -q "^l" ; then

>          cd "$(dirname "$RESUMEDEV")"

>          RESUMEDEV=$(ls -l $RESUMEDEV | awk '{ print $NF }')

>        fi

>        echo "Trying to resume from $RESUMEDEV"

>        RESMAJMIN=$(ls -l $RESUMEDEV | tr , : | awk '{ print $5$6 }')

>        echo $RESMAJMIN

>      fi

Trying to resume from /dev/../dev/../dev/sda2

8:2

So how exactly does your patch actually fix anything at all?

Perhaps this demonstrates what (s)he's getting at:

Code:

gazl@slack:/$ ls -ld /dev/wibble

lrwxrwxrwx 1 root root 6 Mar 17 16:19 /dev/wibble -> ./sda1

gazl@slack:/$ ls -ld /dev/sda1

brw-rw---- 1 root disk 8, 1 Mar 17 16:06 /dev/sda1

gazl@slack:/$ RESUMEDEV='/dev/wibble'

gazl@slack:/$ RESUMEDEV=$(ls -l $RESUMEDEV | awk '{ print $NF }')

gazl@slack:/$ RESMAJMIN=$(ls -l $RESUMEDEV | tr , : | awk '{ print $5$6 }')

ls: cannot access ./sda1: No such file or directory

gazl@slack:/$ echo $RESMAJMIN



gazl@slack:/$

Now, with the printf/stat I came up with above we still obtain the correct major:minor numbers rather than getting a file not found.

Code:

gazl@slack;/$ RESUMEDEV='/dev/wibble'

gazl@slack:/$ printf '%d:%d\n' $(stat -L -c '0x%t 0x%T' $RESUMEDEV)

8:1

Not only is my code shorter, it appears to correctly handle relative symlinks better.

I think the change the OP suggested does the same thing but relies on changing directory in order to get the appropriate result:

Code:

gazl@slack:/$ cd /dev

gazl@slack:/dev$ RESUMEDEV=$(ls -l $RESUMEDEV | awk '{ print $NF }')

gazl@slack:/dev$ RESMAJMIN=$(ls -l $RESUMEDEV | tr , : | awk '{ print $5$6 }')

gazl@slack:/dev$ echo $RESMAJMIN

8:1

BTW, those changes are tested on a real initrd? With BusyBox tools?

We known that the BusyBox utilities sometimes works slighty different... ;)

I've not tried running it in an actual real initrd because I don't use resume, but I have confirmed that the busybox versions of printf and stat commands work as expected.

I don't really care about this issue, I just posted because I saw the ls -l | grep "^l" | awk.... stuff and thought: there must be a better way than that! ;)