[systemd-devel] [PATCH] Correctly parse commented multiline variables

[Michal Vyskocil]

> Hi,
> can you check if it works with the following test case?
> For me it doesn't, and I think there must be a bug.
> 
> Zbyszek

Hi Zbigniew,

sorry for a responding on my initial email, but for some reason your
response[1] did not appear in my mailbox. Anyway your test have raised
an interesting problem - the load_env_file does not parse a variable
definition like shell* do. It considers everything behind quotes as a
variable content and continuation character does not matter.

FOO="this

is
#commented

multiline
variable"

will be properly recognized by shell, but not by systemd. On the other
hand, it will accept definitions like FOO=one two, which has a different
meaning in a shell, so must be quoted. Therefor we shall define
systemd's behavior and of course how much close systemd should mimic
shell.

I'd say systemd can ignore quoting and be a bit stricter than a
shell, so accepts only lines ends on "\\\n" as a continuation and in
this mode accept #comments to be a part of a definition

FOO=this \
is \
#commented \
multiline \
variable

The question is what to do with a definitions ends on a \, followed by
comment

FOO=this \
#is commented

will result in "this #is commented", but this is probably not what
people will expect and it behaves differently than a shell. We might
have a rule definition can't end on a comment, even this sounds a bit
nasty to me.

This is probably the reason, where shell syntax make it clear
FOO="this \
#is commented"

*I've no idea if there are any differences in variable definitions, but
I use dash as the reference one. So just s/shell/dash/

[1] http://lists.freedesktop.org/archives/systemd-devel/2013-February/008566.html

Regards
Michal Vyskocil

On Fri, Feb 01, 2013 at 02:47:24PM +0100, Michal Vyskocil wrote:
> Buffer c must be freeed when code detects a comment or empty string after
> a strip. Otherwise no other variable definitions will be loaded.
[snip]
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