From: Max Nikulin <email@example.com>
Subject: Re: Lazy load of org-protocol
Date: Sun, 6 Feb 2022 23:42:11 +0700 [thread overview]
Message-ID: <firstname.lastname@example.org> (raw)
On 06/02/2022 01:27, Jim Porter wrote:
> On 2/5/2022 3:54 AM, Max Nikulin wrote:
> etc/emacsclient-mail.desktop in the Emacs repo does this.) The command
> to use for a new Emacs instance is simple:
> emacs -f message-mailto %u
> However, doing this for emacsclient is harder:
> emacsclient --alternate-editor= --create-frame --eval
> "(message-mailto \\"%u\\")"
> There's no problem with "--alternate-editor=" and "--create-frame", but
> the fact that emacsclient requires evaling the function call that way
> is: if %u holds a string with quotation marks, this will break, and
> worse, could even result in arbitrary code being executed. (In practice,
> this is probably rare, since URLs are generally URL-encoded, and so
> don't have literal quotes in them.)
Thank you for suggesting another use case.
Quoting issues was the reason why I started to search a better way.
There should be an easy and safe means to pass argument from command
line to evaluated expressions similar to shell
sh -c 'echo "$1"' example 'Hello, World!'
Some people could not even choose proper quotes for shell command:
First recipe and the accepted answer in second source solves the obvious
problem but they miss escaping for elisp expression. Another answer on
stackoverflow is more accurate, it suggests
I suppose, these links is a good illustration that substitution of
arbitrary argument into lisp expression is harder than it should be to
help users to avoid security issues.
> As a result, I think a good first step might be to add support for
> "--funcall" to emacsclient, just like the regular emacs binary. (The
> "-f" shorthand won't work though, since emacsclient already uses that
> for "--server-file"). This would simplify the `message-mailto' case
> above and would also allow org-protocol to do something similar:
> emacsclient --funcall org-protocol-capture %u
No, --funcall is just a sugar for --eval '(func)' that does not contain
arbitrary input, but func has no access to other arguments and it is the
I think, the solution is to add -arg command to emacs server protocol
that pushes its argument to a list and extend -exec command that would
make such list available as argv or as `command-line-args-left' for
evaluated expression. Of course, emacsclient option parser should be
modified as well to support --arg option
emacsclient --eval '(func)' --arg 1 2 3
emacsclient --eval '(func)' --arg -- 1 2 3
and maybe even for multiple eval+arg pairs
emacsclient --eval '(f1)' --arg 'a1' --eval '(f2)' --arg 'a2' 'a3'
The proper place to discuss idea is emacs-devel list, but I am afraid
that without a patch it will be just buried.
> emacsclient --eval "(org-protocol-capture \\"%u\\")"
Due to quoting issues a small wrapper may be safer (modulo -a, -c)
emacsclient --eval "(require 'org-protocol)"
emacsclient -- "$@"
next prev parent reply other threads:[~2022-02-06 16:43 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-05 11:54 Max Nikulin
2022-02-05 18:27 ` Jim Porter
2022-02-06 16:42 ` Max Nikulin [this message]
2022-02-06 19:40 ` Jim Porter
2022-02-07 14:57 ` Max Nikulin
2022-02-07 19:06 ` Jim Porter
2022-02-09 16:46 ` Max Nikulin
2022-02-09 19:22 ` Jim Porter
2022-02-10 14:44 ` Max Nikulin
2022-02-08 10:44 ` Emacs-orgmode Digest, Vol 192, Issue 8 Tianshu Wang
[not found] <email@example.com>
2022-02-08 19:02 ` [PATCH] lisp/org-capture.el: Add hook & hook options to org-capture (Valentin Herrmann) No Wayman
2022-02-09 4:10 ` Ihor Radchenko
2022-02-09 7:11 ` No Wayman
2022-03-20 10:43 ` Ihor Radchenko
2022-02-10 19:32 ` Greg Minshall
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
List information: https://www.orgmode.org/
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this public inbox
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).