Help with sed in a PKGBUILD

Question

Basically, I need to make a few modifications to a conf file but I am no good with sed.  Here is a portion of the original conf file:
our %HTTP_LOG = ("Linux-RHFC" => "/var/log/httpd/access_log",
"Linux-Debian" => "/var/log/apache2/access.log",
"Linux-Gentoo" => "/var/log/apache2/access_log",
"Linux-Slack" => "/var/log/httpd/access.log",
"Linux-SuSE" => "/var/log/apache2/access_log",
"Linux-Generic" => "/var/log/httpd/access_log",
"FreeBSD" => "/var/log/httpd-access.log");
our %BASE_WWW = ("Linux-RHFC" => "/var/www/html",
"Linux-Debian" => "/var/www",
"Linux-Gentoo" => "/var/www/localhost/htdocs",
"Linux-Slack" => "/var/www/htdocs",
"Linux-SuSE" => "/srv/www/htdocs",
"Linux-Generic" => "/usr/local/www",
"FreeBSD" => "/usr/local/www/apache22/data");
I need to make two changes:
1) change the .log to _log in the following:
"Linux-Slack"   => "/var/log/httpd/access.log",
2) change the path from "/var/www/htdocs" to "/srv/http" in the following:
"Linux-Slack"   => "/var/www/htdocs",
Here is a model line with sed making another needed change that res wrote into the PKGBUILD:
sed '/^our $OSTYPE = "Linux-RHFC"/ s,RHFC,Slack,' < $pkgname.conf \
> $pkgdir/etc/$pkgname.conf
Basically, I can't adapt his line to do what I need.  Anyone willing to help me out?  BTW, this is for the monitorix PKGBUILD in the AUR: http://aur.archlinux.org/packages.php?ID=33911
Last edited by graysky (2010-01-26 21:35:28)

Answer 1

CommandLine: (Combined)
sed '/ *"Linux-Slack"/{ s=/var/www=/srv/http=; s=log=_log= }' < infile > outfile
Output:
our %HTTP_LOG = ("Linux-RHFC"   => "/var/log/httpd/access_log",
                "Linux-Debian"  => "/var/log/apache2/access.log",
                "Linux-Gentoo"  => "/var/log/apache2/access_log",
                "Linux-Slack"   => "/var/_log/httpd/access.log",
                "Linux-SuSE"    => "/var/log/apache2/access_log",
                "Linux-Generic" => "/var/log/httpd/access_log",
                "FreeBSD"       => "/var/log/httpd-access.log");
our %BASE_WWW = ("Linux-RHFC"   => "/var/www/html",
                "Linux-Debian"  => "/var/www",
                "Linux-Gentoo"  => "/var/www/localhost/htdocs",
                "Linux-Slack"   => "/srv/http/htdocs",
                "Linux-SuSE"    => "/srv/www/htdocs",
                "Linux-Generic" => "/usr/local/www",
                "FreeBSD"       => "/usr/local/www/apache22/data");
Don't try to write to the original file using this approach as it will clobber your original file. Use "sed -i" to save to the original file instead. The "< infile > outfile" save the output to another file obviously.
Sed Script: ( Invoked as sed -f whatever_you_call_the_script file )
/ *"Linux-Slack"/{
s=/var/www=/srv/http=
s=log=_log=
sed '/^our $OSTYPE = "Linux-RHFC"/ s,RHFC,Slack,' < $pkgname.conf \
                                                    > $pkgdir/etc/$pkgname.conf
This means find this regex pattern ^our $OSTYPE = "Linux-RHFC" and whatever it matches change RHFC to Slack. Take $pkgname.conf as the infile and send the output of sed to $pkgdir/etc/$pkgname.conf
Notice he used s,RHFC,Slack, and I used s=log=_log=. This is typically done if you have a lot of "/" in a file. Sed's typical replacement pattern is this s/original/changed/ but as I mentioned it becomes hard to figure out if you have something like this s/\/mnt\/usb\/somefile/\/mnt\/usb\/somename/. Sed allows you to substitute any character (except a few special ones) in place of "/" in it's replacement pattern as long as you follow through the whole command like that. So in essence these are equivalent s,RHFC,Slack,, s=RHFC=Slack=, s/RHFC/Slack/
You did say you wanted to know. Hope this is what you were looking for or at least a step in the right direction. Sorry if I bored you with the school lession.