Switch to libbsd-overlay

This is more portable than libbsd as everything Just Works, even on BSD systems,
and is the recommended method of consuming libbsd nowadays.

It also helpfully lets things work with glibc-provided functions for new
enough glibc.

Closes: https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/973
Co-authored-by: Guillem Jover <guillem@hadrons.org>
Signed-off-by: Sam James <sam@gentoo.org>
(cherry picked from commit 94945a5274)

include/os.h

@@ -50,16 +50,13 @@ SOFTWARE.
 #include "misc.h"
 #include <stdarg.h>
 #include <stdint.h>
+#if defined(HAVE_REALLOCARRAY)
+#include <stdlib.h>       /* for reallocarray */
+#endif
 #include <string.h>
 #ifdef MONOTONIC_CLOCK
 #include <time.h>
 #endif
-#if defined(HAVE_LIBBSD) && defined(HAVE_REALLOCARRAY)
-#include <bsd/stdlib.h>       /* for reallocarray */
-#endif
-#if defined(HAVE_LIBBSD) && defined(HAVE_STRLCPY)
-#include <bsd/string.h>       /* for strlcpy, strlcat */
-#endif
 
 #define SCREEN_SAVER_ON   0
 #define SCREEN_SAVER_OFF  1

meson.build

@@ -94,7 +94,7 @@ xshmfence_dep = dependency('xshmfence', version: '>= 1.1', required: false)
 xwaylandproto_dep = dependency('xwaylandproto', version: '>= 1.0', fallback: ['xorgproto', 'ext_xorgproto'], required: false)
 
 pixman_dep = dependency('pixman-1')
-libbsd_dep = dependency('libbsd', required: false)
+libbsd_dep = dependency('libbsd-overlay', required: false)
 xkbcomp_dep = dependency('xkbcomp', required: false)
 xkbfile_dep = dependency('xkbfile')
 xfont2_dep = dependency('xfont2', version: '>= 2.0')

os/auth.c

@@ -46,9 +46,7 @@ from The Open Group.
 #ifdef WIN32
 #include    <X11/Xw32defs.h>
 #endif
-#ifdef HAVE_LIBBSD
-#include   <bsd/stdlib.h>       /* for arc4random_buf() */
-#endif
+#include   <stdlib.h>       /* for arc4random_buf() */
 
 struct protocol {
     unsigned short name_length;