On Wed, Jun 14, 2017 at 12:59:04PM +0200, Thorsten Glaser wrote:
For the backslashes case, the attached ought to do. Would you be willing to
test it? It should apply to /var/lib/dpkg/info/slapd.postinst.
The patch works as-is, however, as a shell author and informed about
writing portable shell scripts, I’m a tad concerned about the use of
the accent gravis form of command substitution, especially as it can
*not* be quoted both inside and outside (which is not the case here,
but someone might decide to do that in the future).
Therefore I’m urging you to change the last addition to…
+ grep "olcDbDirectory:" $(grep -Fl "olcSuffix: $1"
${SLAPD_CONF}/cn\=config/olcDatabase*.ldif) | cut -d: -f 2 | sed 's/^ *//g'
… or possibly, quoting, just to be safe:
+ grep "olcDbDirectory:" "$(grep -Fl "olcSuffix: $1"
"${SLAPD_CONF}/cn\=config/olcDatabase*.ldif")" | cut -d: -f 2 | sed 's/^ *//g'
(Side note, I cringe every time I see such grep|cut|sed thingies,
this can almost certainly be done with just sed¹.)
Agreed on all points. The code that uses backticks and grep|cut|sed is
mostly from before my time. I don't have the energy for a wholesale
update of the code style, but I'm updating pieces to a style like you
suggest as I touch them. The diff was meant as an example of a very
minimal change that would be suitable for backporting to stable, or
applying to a customer system in your case.
I have to check more closely but I think the lack of quoting around the
second grep may be intentional. I have a vague recollection of a case
where it was valid to have multiple databases configured for the same
suffix.
Still thinking about the base64 case. Since we use the suffix to name files
and directories for backup and restore, I guess it's most robust to just use
the base64 directly - even if it's not quite as nice for showing to users.
Remember that that can span multiple lines (although this is also true
for the non-base64 base). I usually just read LDIF line by line in my
shell scripts concatenating as needed, but for quick, I’ve found this
useful:
cat² x.ldif | tr '\n' '\001' | sed $'s/\001 //g' | tr '\001' '\n' >y
Possibly less portable, but for scripts targeted at Debian I've
generally used a perl one-liner:
perl -00 -pe 's/\n[ \t]//g; s/^#.*\n//mg' "$@"
In any case I'm trying to (gradually...) update the maintainer scripts
to use slapcat instead of parsing the config backend files directly,
which comes with a '-o ldif-wrap=no' option.
