GNU bug report logs - #76982
30.1; url-generic-parse-url cannot parse Windows file paths

Previous Next

Full log

Message #11 received at 76982 <at> debbugs.gnu.org (full text, mbox):

From: Eli Zaretskii <eliz <at> gnu.org>
To: Sebastián Monía <sebastian <at> sebasmonia.com>
Cc: 76982 <at> debbugs.gnu.org, morgan <at> ice9.digital
Subject: Re: bug#76982: 30.1;
 url-generic-parse-url cannot parse Windows file paths
Date: Thu, 13 Mar 2025 10:20:41 +0200

> Cc: 76982 <at> debbugs.gnu.org
> From: Sebastián Monía
>  <sebastian <at> sebasmonia.com>
> Date: Wed, 12 Mar 2025 15:23:08 -0400
> 
> Morgan Willcock <morgan <at> ice9.digital> writes:
> 
> >   (url-filename (url-generic-parse-url "file:///c:/windows"))
> >   => "/c:/windows"
> >
> >   (url-filename (url-generic-parse-url "c:/windows"))
> >   => "/windows"
> >
> > This is relevant in functions such as
> > mml-expand-html-into-multipart-related, where there is a check that the
> > file exists:
> >
> >   (when (and (null (url-type parsed))
> >              (not (zerop (length (url-filename parsed))))
> >              (file-exists-p (url-filename parsed)))
> >     ...)
> >
> > An example of a real world problem is being unable to reliably send HTML
> > mail when using Windows:
> >
> > https://github.com/jeremy-compostella/org-msg/issues/122
> 
> Attached a potential patch.

Thanks.

> >From 25c0cbeb1523e3fed3d3409465b6dcc99c967a38 Mon Sep 17 00:00:00 2001
> From: =?UTF-8?q?Sebasti=C3=A1n=20Mon=C3=ADa?=
>  <sebastian.monia <at> sebasmonia.com>
> Date: Wed, 12 Mar 2025 15:16:19 -0400
> Subject: [PATCH] url-parse.el: Parsing exceptions for Windows paths
>  (bug#76982)

Please add a ChangeLog-style list of functions that are modified and a
short description of each modification.

> 
> ---
>  lisp/url/url-parse.el | 14 +++++++++++++-
>  1 file changed, 13 insertions(+), 1 deletion(-)
> 
> diff --git a/lisp/url/url-parse.el b/lisp/url/url-parse.el
> index 4c65721b83d..1dff66c6228 100644
> --- a/lisp/url/url-parse.el
> +++ b/lisp/url/url-parse.el
> @@ -83,7 +83,12 @@ url-recreate-url
>  	 ;; port is empty or if its value would be the same as that of
>  	 ;; the scheme's default."
>  	 (port (url-port-if-non-default urlobj))
> -	 (file (url-filename urlobj))
> +         ;; For Windows/DOS-like paths, `url-generic-parse-url' strips
> +         ;; the leading /, so we need to add it back (bug#76982)
> +	 (file (if (and (string= "file" type)
> +                        (string-match "^[A-Za-z]:[/\\]" (url-filename urlobj)))
> +                   (concat "/" (url-filename urlobj))
> +                 (url-filename urlobj)))
>  	 (frag (url-target urlobj)))
>      (concat (if type (concat type ":"))
>  	    (if (url-fullness urlobj) "//")

OK.

> @@ -210,6 +215,13 @@ url-generic-parse-url
>  
>            (if (and host (string-match "%[0-9][0-9]" host))
>                (setq host (url-unhex-string host)))
> +
> +          ;; For file:// URIs, if the path "looks like" Windows/DOS, it
> +          ;; makes sense to strip the leading slash (bug#76982)
> +          (when (and (string= "file" scheme)
> +                     (string-match "^/[A-Za-z]:[/\\]" file))
> +            (setq file (substring file 1)))
> +
>            (url-parse-make-urlobj scheme user pass host port file
>  				 fragment nil full))))))

Isn't it cleaner to go one more character forward here:

          ;; 3.2. Authority
          (when (looking-at "//")
            (setq full t)
            (forward-char 2)  <<<<<<<<<<<<<<<<<<<<
            (setq save-pos (point))
            (skip-chars-forward "^/?#")

if the conditions for Windows-style absolute file name are fulfilled?

Also, could we please have some simple tests for this?

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.