xwayland: port + un-defer; systemic autotools maintainer-mode fix

Un-defer xwayland in config/redbear-full.toml (it is a kwin build dependency).
Getting it to build required:

- cook_build script.rs: cookbook_configure now defeats autotools maintainer-mode
  regeneration. Release tarballs ship a complete build system, but extraction
  timestamp skew makes make re-run the version-pinned aclocal-<N>/automake-<N>
  the tarball was generated with, which the host (a different automake) lacks
  ('aclocal-1.NN: command not found'). Force generated files newer than their
  sources (staggered mtimes) and no-op ACLOCAL/AUTOMAKE/AUTOCONF/AUTOHEADER as a
  safety net. This unblocked the whole X11 autotools stack (libxcb, libx11,
  libxfont2, libxkbfile, ...) with no per-recipe edits.

- xwayland recipe: meson -> custom template so it can (1) overlay the host
  wayland-scanner onto the sysroot path meson resolves (the sysroot scanner is a
  Redox binary, unrunnable on the build host; it is a build-time-only generator
  emitting arch-independent C), and (2) unset COOKBOOK_DYNAMIC so the cross
  pkg-config resolves --static, pulling the X11 libs' Requires.private closure
  (xcb -> xau) — those libs are static-only on Redox (libtool has no Redox
  shared support), so the closure was otherwise dropped and the link failed on
  XauGetBestAuthByAddr/XauDisposeAuth.

- os/access.c: include <sys/utsname.h> on __redox__ (Redox lacks SIOCGIFCONF so
  the uname()-based DefineSelf is compiled; relibc provides uname/struct utsname).

Produces a proper Redox /usr/bin/Xwayland ELF.

config/redbear-full.toml

@@ -69,7 +69,7 @@ packages = [
     # (malformed hunk counts + wrong a/source vs b/source-new strip prefix) and
     # needs full regeneration. xwayland is X11-app compat under Wayland, NOT
     # required for the SDDM login / Plasma-Wayland session. Re-add once vendored.
-    # "xwayland",
+    "xwayland",
 ]
 
 [package_groups.kde-desktop]
@@ -237,7 +237,7 @@ pam-redbear = {}
 polkit = {}
 polkit-qt6 = {}
 sddm = {}
-# xwayland = {}  # deferred — see packages[] TODO(xwayland)
+xwayland = {}
 
 # D-Bus Rust bindings + media
 zbus = {}

local/recipes/wayland/xwayland/recipe.toml

@@ -12,7 +12,7 @@ version = "24.1.8"
 #   upstream: https://www.x.org/releases/individual/xserver/xwayland-24.1.8.tar.xz
 path = "source"
 [build]
-template = "meson"
+template = "custom"
 dependencies = [
     "libpthread-stubs",
     "libepoxy",
@@ -39,10 +39,35 @@ dependencies = [
     # Per local/AGENTS.md LINUX KERNEL SOURCE POLICY: Linux as reference only.
     "redbear-input-headers",
 ]
-mesonflags = [
-    "-Ddrm=false",
-    "-Dglamor=false",
-    "-Dglx=false",
-    "-Dsecure-rpc=false",
-    "-Dmitshm=false",
-]
+script = """
+DYNAMIC_INIT
+
+# xwayland's hw/xwayland/meson.build resolves wayland-scanner from the cross
+# wayland-scanner.pc, which reports the sysroot (Redox) binary — unrunnable on
+# the build host. wayland-scanner is a build-time code generator (reads protocol
+# XML, emits arch-independent C) and is never shipped, so overlay the host
+# binary onto the sysroot path the generator will invoke.
+if [ -x /usr/bin/wayland-scanner ]; then
+    cp -f /usr/bin/wayland-scanner "${COOKBOOK_SYSROOT}/usr/bin/wayland-scanner"
+fi
+
+COOKBOOK_MESON_FLAGS+=(
+    -Ddrm=false
+    -Dglamor=false
+    -Dglx=false
+    -Dsecure-rpc=false
+    -Dmitshm=false
+)
+
+# The X11 client libraries (libxcb, libXau, libXdmcp, ...) build static-only on
+# Redox (libtool has no Redox shared-lib support), and their inter-lib deps live
+# in pkg-config Requires.private (e.g. xcb -> xau). The cross pkg-config wrapper
+# only adds --static (which pulls Requires.private) when COOKBOOK_DYNAMIC is
+# unset; DYNAMIC_INIT set it, so the static closure was dropped and xwayland's
+# link failed on XauGetBestAuthByAddr/XauDisposeAuth. Unset it so pkg-config
+# resolves the full static closure. The genuinely-shared deps (libwayland,
+# relibc) still link as .so — the extra -l entries just resolve against them.
+unset COOKBOOK_DYNAMIC
+
+cookbook_meson
+"""

local/recipes/wayland/xwayland/source/os/access.c

@@ -124,7 +124,9 @@ SOFTWARE.
 #include <sys/un.h>
 #endif
 
-#if defined(SVR4) ||  (defined(SYSV) && defined(__i386__)) || defined(__GNU__)
+#if defined(SVR4) ||  (defined(SYSV) && defined(__i386__)) || defined(__GNU__) || defined(__redox__)
+/* Redox lacks SIOCGIFCONF, so the uname()-based DefineSelf below is compiled;
+ * relibc provides uname()/struct utsname, so pull in the header on Redox. */
 #include <sys/utsname.h>
 #endif
 #if defined(SYSV) &&  defined(__i386__)

src/cook/script.rs

@@ -230,6 +230,35 @@ COOKBOOK_CONFIGURE_FLAGS=(
 COOKBOOK_MAKE="make"
 
 function cookbook_configure {
+    # Defeat autotools maintainer-mode regeneration. Release tarballs ship a
+    # complete, consistent build system, but extraction timestamp skew makes
+    # make think aclocal.m4/configure/Makefile.in are stale and re-run the
+    # version-pinned aclocal-<N>/automake-<N> the tarball was generated with —
+    # which the host (a different automake) lacks, aborting with "aclocal-1.NN:
+    # command not found". Force the generated files newer than their sources so
+    # the regen rules never fire. Harmless for recipes with no autotools files,
+    # and for recipes that intentionally regenerated in their [source] script
+    # (that fresh configure just gets forward-dated).
+    if [ -n "${COOKBOOK_SOURCE}" ] && [ -d "${COOKBOOK_SOURCE}" ]; then
+        # Stagger timestamps so each generated file is strictly newer than its
+        # prerequisites: sources (2000) < aclocal.m4 (2001) < configure/
+        # config.h.in/Makefile.in (2002). Equal mtimes make GNU make rebuild.
+        find "${COOKBOOK_SOURCE}" '(' -name 'configure.ac' -o -name 'configure.in' -o -name 'Makefile.am' -o -name 'acinclude.m4' ')' -exec touch -t 200001010000 {} + 2>/dev/null || true
+        find "${COOKBOOK_SOURCE}" -name '*.m4' -path '*/m4/*' -exec touch -t 200001010000 {} + 2>/dev/null || true
+        find "${COOKBOOK_SOURCE}" -name 'aclocal.m4' -exec touch -t 200101010000 {} + 2>/dev/null || true
+        find "${COOKBOOK_SOURCE}" '(' -name 'configure' -o -name 'config.h.in' -o -name 'Makefile.in' ')' -exec touch -t 200201010000 {} + 2>/dev/null || true
+    fi
+    # Safety net: if make still triggers a maintainer-mode regen rule (e.g. a
+    # nested Makefile.in whose prereqs include host-installed m4 macros with
+    # newer mtimes), no-op the version-pinned autotools instead of invoking the
+    # absent aclocal-1.NN/automake-1.NN. configure's AM_MISSING_PROG honors these
+    # pre-set values, so the generated Makefiles inherit the no-ops. The shipped
+    # build files are already correct, so skipping regeneration is safe.
+    export ACLOCAL="${ACLOCAL:-true}"
+    export AUTOMAKE="${AUTOMAKE:-true}"
+    export AUTOCONF="${AUTOCONF:-true}"
+    export AUTOHEADER="${AUTOHEADER:-true}"
+    export AUTORECONF="${AUTORECONF:-true}"
     "${COOKBOOK_CONFIGURE}" "${COOKBOOK_CONFIGURE_FLAGS[@]}" "$@"
     "${COOKBOOK_MAKE}" -j "${COOKBOOK_MAKE_JOBS}"
     "${COOKBOOK_MAKE}" install DESTDIR="${COOKBOOK_STAGE}"