Re: [PATCH] bind_textdomain_codeset: don't return failure unless encoding isn't UTF-8

[Rich Felker <dalias@libc.org>]

[-- Attachment #1: Type: text/plain, Size: 3621 bytes --]

On Fri, Dec 30, 2016 at 04:13:44PM -0600, Laine Gholson wrote:
> option 1 is the only sane choice, and I don't see how something
> could break unless they constantly check for the GNU behavior and
> break if it isn't the GNU behavior, in which case it is the
> program's fault anyways.

Does the attached patch look reasonable? The "UTF8" alternative could
be added separately if needed; did you find software that's passing
the string without the '-'?

I think the main functional difference from your patch is that "UTF-8"
is returned in the case where the codeset argument is null.

Rich


> On 12/29/16 21:14, Rich Felker wrote:
> >On Fri, Dec 16, 2016 at 10:59:54PM -0500, Rich Felker wrote:
> >>On Sat, Dec 03, 2016 at 09:04:42PM -0600, Laine Gholson wrote:
> >>>returning null broke a vlc media player built with gettext support
> >>
> >>>>From 2f79aa294db5d9230ad71298e3de4b5561b441be Mon Sep 17 00:00:00 2001
> >>>From: Laine Gholson <laine.gholson@gmail.com>
> >>>Date: Wed, 9 Nov 2016 20:19:00 -0600
> >>>Subject: [PATCH] bind_textdomain_codeset: don't return failure unless encoding isn't UTF-8
> >>>
> >>>VLC isn't happy when bind_textdomain_codeset returns NULL
> >>>---
> >>> src/locale/bind_textdomain_codeset.c | 4 +++-
> >>> 1 file changed, 3 insertions(+), 1 deletion(-)
> >>>
> >>>diff --git a/src/locale/bind_textdomain_codeset.c b/src/locale/bind_textdomain_codeset.c
> >>>index 5ebfd5e..e5f3f52 100644
> >>>--- a/src/locale/bind_textdomain_codeset.c
> >>>+++ b/src/locale/bind_textdomain_codeset.c
> >>>@@ -5,7 +5,9 @@
> >>> III
> >>> char *bind_textdomain_codeset(const char *domainname, const char *codeset)
> >>> {
> >>>-	if (codeset && strcasecmp(codeset, "UTF-8"))
> >>>+	if (codeset && ((strcasecmp(codeset, "UTF-8") == 0) || (strcasecmp(codeset, "UTF8") == 0))) {
> >>>+		return "UTF-8";
> >>>+	} else if (codeset)
> >>> 		errno = EINVAL;
> >>> 	return NULL;
> >>> }
> >>>--
> >>>2.10.2
> >>
> >>I think this needs some more thought. The documentation of the API is
> >>that a null pointer argument/result means "the locale's character
> >>encoding", and that the default is null; presumably even when the
> >>locale's codeset is "foo", null (default) and "foo" are still
> >>different states.
> >>
> >>I don't actually like that, and don't think we should copy it --
> >>especially since, now that we also have a C locale with "ASCII" as the
> >>codeset, we _can't_ provide a codeset matching the locale in all cases
> >>-- but I also don't think it's right for the return value (null or
> >>"UTF-8") to depend on the argument rather than on the "previous state"
> >>like it's documented to.
> >>
> >>There seem to be two possible reasonable behaviors:
> >>
> >>1. Diverge from the GNU behavior and treat textdomains as always-bound
> >>   to "UTF-8", regardless of whether bind_textdomain_codeset has been
> >>   called. The function would then return a null pointer with EINVAL
> >>   set for strings other than "UTF-8"/"UTF8", and would return "UTF-8"
> >>   for a valid or null-pointer argument.
> >>
> >>2. Keep a 1-bit state for each textdomain reflecting whether its
> >>   nominally in "default" mode or "UTF-8" mode. Either way the
> >>   original UTF-8 string would be returned; the only point of the
> >>   state would be providing a return value for bind_textdomain_codeset
> >>   that reflects how it was previously called.
> >>
> >>Being that 2 is gratuitous complexity to do something stupid and
> >>meaningless, I'd lean towards 1, but I don't want to break anything
> >>that works. Does this seem safe to do?
> >
> >Ping. Anyone else have thoughts on this?
> >
> >Rich
> >

[-- Attachment #2: btdc.diff --]
[-- Type: text/plain, Size: 470 bytes --]

diff --git a/src/locale/bind_textdomain_codeset.c b/src/locale/bind_textdomain_codeset.c
index 5ebfd5e..240e83e 100644
--- a/src/locale/bind_textdomain_codeset.c
+++ b/src/locale/bind_textdomain_codeset.c
@@ -5,7 +5,9 @@
 
 char *bind_textdomain_codeset(const char *domainname, const char *codeset)
 {
-	if (codeset && strcasecmp(codeset, "UTF-8"))
+	if (codeset && strcasecmp(codeset, "UTF-8")) {
 		errno = EINVAL;
-	return NULL;
+		return 0;
+	}
+	return "UTF-8";
 }