## Comment every line containing the $pattern given
## Ex: preserve a record of an old value before changing it.
## 
## $comment_lines('/etc/resolv.conf', 'nameserver')
## echo "nameserver 192.168.0.1" >> /etc/resolv.conf
## 
#def comment_lines($filename, $pattern, $commentchar='#')
perl -npe 's/^(.*${pattern}.*)$/${commentchar}\${1}/' -i '$filename'
#end def

## Comments every line which contains only the exact pattern.
## This one works like comment_lines(), except that a line cannot contain any
## additional text.
#def comment_lines_exact($filename, $pattern, $commentchar='#')
perl -npe 's/^(${pattern})$/${commentchar}\${1}/' -f '$filename'
#end def

## Uncomments every (commented) line containing the pattern
## Patterns should not contain the #
## Ex: enable all the suggested values in the Samba configuration
## (This isn't the greatest example, but it makes a point)
## 
## $uncomment_lines('/etc/samba/smb.conf', ';')
## 
#def uncomment_lines($filename, $pattern, $commentchar='#')
perl -npe 's/^[ \t]*${commentchar}(.*${pattern}.*)$/\${1}/' -i '$filename'
#end def

## Nullify (by changing to 'true') all instances of a given sh command. This
## does understand lines with multiple commands (separated by ';') and also
## knows to ignore comments. Consider other options before using this
## method.
## Ex: remove 'exit 0' commands from a shell script, so that we can append the
## script and be relatively certain that the new parts will be executed.
## 
## $delete_command('etc/cron.daily/some_script.sh', 'exit[ \t]*0')
## echo '# More scipt' >> /etc/cron.daily/some_script.sh
## 
#def delete_command($filename, $pattern)
sed -nr '
    h
    s/^([^#]*)(#?.*)$/\1/
    s/((^|;)[ \t]*)${pattern}([ \t]*($|;))/\1true\3/g
    s/((^|;)[ \t]*)${pattern}([ \t]*($|;))/\1true\3/g
    x
    s/^([^#]*)(#?.*)$/\2/
    H
    x
    s/\n//
    p
' -i '$filename'
#end def

## Replace a configuration parameter value, or add it if it doesn't exist.
## Assumes format is [param_name] [value]
## Ex: Change the maximum password age to 30 days
## 
## $set_config_value('/etc/login.defs', 'PASS_MAX_DAYS', '30')
## 
#def set_config_value($filename, $param_name, $value)
if [ -n \"\$(grep -Ee '^[ \t]*${param_name}[ \t]+' '$filename')\" ]
then
    perl -npe 's/^([ \t]*${param_name}[ \t]+)[\x21-\x7E]*([ \t]*(#.*)?)$/\${1}${sedesc($value)}\${2}/' -i '$filename'
else
    echo '$param_name $value' >> '$filename'
fi
#end def

## Replace a configuration parameter value, or add it if it doesn't exist.
## Assues format is [param_name] [delimiter] [value], where [delimiter] is
## usually '='.
## This works the same way as set_config_value(), except that this version
## is used if a character separates a parameter from its value.
#def set_config_value_delim($filename, $param_name, $delim, $value)
if [ -n \"\$(grep -Ee '^[ \t]*${param_name}[ \t]*${delim}[ \t]*' '$filename')\" ]
then
    perl -npe 's/^([ \t]*${param_name}[ \t]*${delim}[ \t]*)[\x21-\x7E]*([ \t]*(#.*)?)$/${1}${sedesc($value)}${2}/' -i '$filename'
else
    echo '$param_name$delim$value' >> '$filename'
fi
#end def

## Copy a file from the server to the client.
## Ex: Copy a template for samba configuration
## 
## (once at the top of the kickstart template)
## #set files = $snippetsdir + '/files/'
## (when you need to copy a file)
## $copy_over_file('etc/samba/smb.conf', '/etc/samba/smb.conf')
## 
## Additionally, copied files can be templated:
## ---------etc/samba/smb.conf-------------
## ...
## [global]
##     server string = $profile_name
## ...
## ----------------------------------------
#def copy_over_file($serverfile, $clientfile)
cat << 'EOF' > '$clientfile'
#include $files + $serverfile
EOF
#end def

## Copy a file from the server and append the contents to a file on the
## client.
## This works the same as copy_over_file(), except it appends the file rather
## than replacing the file.
#def copy_append_file($serverfile, $clientfile)
cat << 'EOF' >> '$clientfile'
#include $files + $serverfile
EOF
#end def

## Convenience function: Copy/append several files at once. This accepts a
## list of tuples. The first element indicates whether to overwrite ('w') or
## append ('a'). The second element is the file name on both the server and
## the client (a '/' is prepended on the client side).
## Ex: copy a template for samba and audit configuration
## 
## $copy_files([
##     ('w', 'etc/samba/smb.conf'),
##     ('w', 'etc/audit.rules'),
## ])
## 
#def copy_files($filelist)
#for $thisfile in $filelist
#if $thisfile[0] == 'a'
$copy_append_file($thisfile[1], '/' + $thisfile[1])
#else
$copy_over_file($thisfile[1], '/' + $thisfile[1])
#end if
#end for
#end def

## Append some content to the todo file. NOTE: $todofile must be defined
## before using this (unless you want unexpected results). Be sure to end
## the content with 'EOF'
## Ex: Instruct the admin to set an appropriate nameserver.
## 
## (once at the top of the kickstart template)
## #set global $todofile = '/root/kstodo'
## (as needed)
## $TODO()
## Edit /etc/resolv.conf to configure your local nameserver
## EOF
## 
## This will prevent inconsistency and accidents. You should avoid using:
## 
## echo "Edit /etc/resolv.conf..." >> /root/kstodo
## 
## It's easy to forget to use >> to append instead of >, which will clobber all
## previous todo notices. It's also easy to forget the filename, was it kstodo
## or ks-todo?
#def TODO()
cat << 'EOF' >> '$todofile'
#end def

## Set the owner, group, and permissions for several files. Assignment can
## be plain ('p') or recursive. If recursive you can assign everything ('r')
## or just files ('f'). This method takes a list of tuples. The first element
## of each indicates which style. The remaining elements are owner, group,
## and mode respectively. If 'f' is used, an additional element is a find
## pattern that can further restrict assignments (use '*' if no additional
## restrict is desired).
## NOTE: I used the word 'plain' instead of 'single', because wildcards can
##       still be used in 'plain' mode.
## Ex: correct the permissions of serveral important files and directories:
## 
## $set_permissions([
##     ('p', 'root', 'root', '700', '/root'),
##     ('f', 'root', 'root', '600', '/root', '*'),
##     ('r', 'root', 'root', '/etc/cron.*'),
##     ('p', 'root', 'root', '644', '/etc/samba/smb.conf'),
## ])
## 
#def set_permissions($filelist)
#for $file in $filelist
#if $file[0] == 'p'
#if $file[1] != '' and $file[2] != ''
chown '$file[1]:$file[2]' '$file[4]'
#else
#if $file[1] != ''
chown '$file[1]' '$file[4]'
#end if
#if $file[2] != ''
chgrp '$file[2]' '$file[4]'
#end if
#end if
#if $file[3] != ''
chmod '$file[3]' '$file[4]'
#end if
#elif $file[0] == 'r'
#if $file[1] != '' and $file[2] != ''
chown -R '$file[1]:$file[2]' '$file[4]'
#else
#if $file[1] != ''
chown -R '$file[1]' '$file[4]'
#end if
#if $file[2] != ''
chgrp -R '$file[2]' '$file[4]'
#end if
#end if
#if $file[3] != ''
chmod -R '$file[3]' '$file[4]'
#end if
#elif $file[0] == 'f'
#if $file[1] != '' and $file[2] != ''
find $file[4] -name '$file[5]' -type f -exec chown -R '$file[1]:$file[2]' {} \;
#else
#if $file[1] != ''
find $file[4] -name '$file[5]' -type f -exec chown -R '$file[1]' {} \;
#end if
#if $file[2] != ''
find $file[4] -name '$file[5]' -type f -exec chgrp -R '$file[2]' {} \;
#end if
#end if
#if $file[3] != ''
find $file[4] -name '$file[5]' -type f -exec chmod -R '$file[3]' {} \;
#end if
#end if
#end for
#end def

## Cheeseball an entire directory.
## This will include (in sequence) all file in a given directory into a
## kickstart template.
## Ex: include a 'misc' directory of templates
## 
## $includeall('misc')
## 
## Now in cobbler/snippets/misc:
## ---------------avinstall-----------------
## wget http://some.server.com/some-av-package.tar.gz
## tar -xzf some-av-package.tar.gz
## ./some-av-package/install.sh
## rm some-av-package.tar.gz
## rm -rf some-av-package
## -----------------------------------------
## ---------------fwinstall-----------------
## wget http://some.server.com/fw-linux-installer.sh
## chmod +x fw-linux-installer.sh
## ./fw-linux-installer.sh
## rm fw-linux-installer.sh
## -----------------------------------------
## 
#def includeall($dir)
#import os
#for $file in $os.listdir($snippetsdir + '/' + $dir)
#include $snippetsdir + '/' + $dir + '/' + $file
#end for
#end def