Re: [musl] setlocale() again

[Alastair Houghton <ahoughton@apple.com>]

On 5 Dec 2023, at 15:19, Alastair Houghton <ahoughton@apple.com> wrote:
> 
>> Maybe I’ve missed a reply somewhere along the lines; here’s a tentative patch that just does the simple thing of making setlocale(LC_ALL, "") pick the C.UTF-8 locale if it’s unable to find the locale specified in the environment.
> 
> [snip]
> 
> Hah. So, testing that patch, having removed my hacks to avoid using Musl’s locale support, I find it doesn’t actually work (for two reasons; one, NULL doesn’t mean not found, it means “use ‘C’”; and two, there is some very odd code in setlocale.c that causes things to go wrong if the specified name is longer than LOCALE_NAME_MAX).
> 
> I’ll come back with an updated patch in a bit.

Updated patch:

==== Cut here ====
diff --git a/src/locale/locale_map.c b/src/locale/locale_map.c
index da61f7fc..097da1ad 100644
--- a/src/locale/locale_map.c
+++ b/src/locale/locale_map.c
@@ -31,7 +31,7 @@ static const char envvars[][12] = {
 volatile int __locale_lock[1];
 volatile int *const __locale_lockptr = __locale_lock;
 
-const struct __locale_map *__get_locale(int cat, const char *val)
+const struct __locale_map *__get_locale(int cat, const char *locale)
 {
 	static void *volatile loc_head;
 	const struct __locale_map *p;
@@ -39,6 +39,7 @@ const struct __locale_map *__get_locale(int cat, const char *val)
 	const char *path = 0, *z;
 	char buf[256];
 	size_t l, n;
+	const char *val = locale;
 
 	if (!*val) {
 		(val = getenv("LC_ALL")) && *val ||
@@ -92,22 +93,18 @@ const struct __locale_map *__get_locale(int cat, const char *val)
 		}
 	}
 
-	/* If no locale definition was found, make a locale map
-	 * object anyway to store the name, which is kept for the
-	 * sake of being able to do message translations at the
-	 * application level. */
-	if (!new && (new = malloc(sizeof *new))) {
-		new->map = __c_dot_utf8.map;
-		new->map_size = __c_dot_utf8.map_size;
-		memcpy(new->name, val, n);
-		new->name[n] = 0;
-		new->next = loc_head;
-		loc_head = new;
-	}
+	/* If no locale definition was found, and we specified a
+	 * locale name of "", return the C.UTF-8 locale. */
+	if (!new && !*locale) new = (void *)&__c_dot_utf8;
 
 	/* For LC_CTYPE, never return a null pointer unless the
 	 * requested name was "C" or "POSIX". */
 	if (!new && cat == LC_CTYPE) new = (void *)&__c_dot_utf8;
 
+	/* Returning NULL means "C locale"; if we get here and
+	 * there's no locale, return failure instead. */
+	if (!new)
+		return LOC_MAP_FAILED;
+
 	return new;
 }
diff --git a/src/locale/setlocale.c b/src/locale/setlocale.c
index 360c4437..9842d95d 100644
--- a/src/locale/setlocale.c
+++ b/src/locale/setlocale.c
@@ -28,12 +28,14 @@ char *setlocale(int cat, const char *name)
 			const char *p = name;
 			for (i=0; i<LC_ALL; i++) {
 				const char *z = __strchrnul(p, ';');
-				if (z-p <= LOCALE_NAME_MAX) {
+				if (z-p > LOCALE_NAME_MAX)
+					lm = LOC_MAP_FAILED;
+				else {
 					memcpy(part, p, z-p);
 					part[z-p] = 0;
 					if (*z) p = z+1;
+					lm = __get_locale(i, part);
 				}
-				lm = __get_locale(i, part);
 				if (lm == LOC_MAP_FAILED) {
 					UNLOCK(__locale_lock);
 					return 0;
==== Cut here ====