51889: fix module loading problem with full RELRO

If full RELRO (relocation read-only, one of the security enhancement
methods for ELF-based systems) is used when building zsh (as in binary
packages of most Linuxes), loading a module (e.g. zsh/zftp) fails unless
all the modules it depends on are already loaded. With this patch the
necessary modules are automatically loaded.

ChangeLog

@@ -1,5 +1,9 @@
 2023-06-26  Jun-ichi Takimoto  <takimoto-j@kba.biglobe.ne.jp>
 
+	* 51889: Src/Modules/zftp.c, Src/mkbltnmlst.sh: enable loading a
+	module (e.g. zftp) that depends on other modules even if zsh is
+	built with the full RELRO
+
 	* 51884: Doc/Zsh/params.yo, Src/params.c, Src/utils.c,
 	Test/D04parameter.ztst: if MULTIBYTE option is on and IFS contains
 	invalid bytes in curret locale then reset it to default

Src/Modules/zftp.c

@@ -3172,7 +3172,7 @@ static struct features module_features = {
 int
 setup_(UNUSED(Module m))
 {
-    return (require_module("zsh/net/tcp", NULL, 0) == 1);
+    return 0;
 }
 
 /**/

Src/mkbltnmlst.sh

@@ -76,6 +76,30 @@ for x_mod in $x_mods; do
     test "x$linked" = xno && echo "#endif"
 done
 
+# if dynamic module 'mod' with load=no has moddeps in its .mdd,
+# then output add_dep(mod, dep) for each 'dep' in moddeps.
+dyn_mods="`grep ' link=dynamic .* load=no ' $CFMOD | \
+          sed -e '/^#/d' -e 's/ .*/ /' -e 's/^name=/ /'`"
+
+for mod in $dyn_mods; do
+    modfile="`grep '^name='$mod' ' $CFMOD | \
+              sed -e 's/^.* modfile=//' -e 's/ .*//'`"
+    if test "x$modfile" = x; then
+	echo >&2 "WARNING: no name for \`$mod' in $CFMOD (ignored)"
+	continue
+    fi
+    unset moddeps
+    . $srcdir/../$modfile
+    if test -n "$moddeps"; then
+        echo '#ifdef DYNAMIC'
+        echo "/* non-linked-in known module \`$mod' */"
+        for dep in $moddeps; do
+          echo "  add_dep(\"$mod\", \"$dep\");"
+        done
+        echo '#endif'
+    fi
+done
+
 echo
 done_mods=" "
 for bin_mod in $bin_mods; do