commit f0678b77c63a9dc8aa32c781cc38bab77932669d
from: Thomas Adam <thomas@xteddy.org>
via: Thomas Adam <thomas.adam@smoothwall.net>
date: Tue Sep 21 20:55:42 2021 UTC

sterror: use XPG version on GLIBC

It looks like autoconf 2.69 will not provide XPG strerror_r even
if the appropriate macros are set which request the XPG version.

Until this is fixed in autoconf and that version is more widely-adopted,
this approach will provide what's required.

Originally from Stefan Sperling, tweaked by me.

commit - 7293142804d9e432cda75b24e7987b55640bcaab
commit + f0678b77c63a9dc8aa32c781cc38bab77932669d
blob - 4ad6d22aa77f19cf6105fcd6bc22a98e92d55ef7
blob + 3173307f2ab8682ed6c74f18e1dcce9c02344d9d
--- lib/error.c
+++ lib/error.c
@@ -37,6 +37,14 @@
 
 #ifndef nitems
 #define nitems(_a) (sizeof(_a) / sizeof((_a)[0]))
+#endif
+
+#if defined(__GLIBC__)
+	/*
+	 * The autoconf test for strerror_r is broken in current versions
+	 * of autoconf: https://savannah.gnu.org/support/?110367
+	 */
+#define strerror_r __xpg_strerror_r
 #endif
 
 static struct got_custom_error {
@@ -144,7 +152,15 @@ got_error_from_errno_fmt(const char *fmt, ...)
 	vsnprintf(buf, sizeof(buf), fmt, ap);
 	va_end(ap);
 
+#ifdef __GLIBC__
+	/*
+	 * The autoconf test for strerror_r is broken in current versions
+	 * of autoconf: https://savannah.gnu.org/support/?110367
+	 */
+	__xpg_strerror_r(errno, strerr, sizeof(strerr));
+#else
 	strerror_r(errno, strerr, sizeof(strerr));
+#endif
 	snprintf(cerr->msg, sizeof(cerr->msg), "%s: %s", buf, strerr);
 
 	err->code = GOT_ERR_ERRNO;