ash: fix FUNCNAME issue

Commit c13f77823 (ash: adjust reinitvar() to allow for FUNCNAME)
was incomplete.  It didn't correctly pass the funcname variable
during forkshell.  This resulted in horrible failure when running
a function like:

   f() { (echo $FUNCNAME); }

1 files changed, 5 insertions, 0 deletions

diff --git a/shell/ash.c b/shell/ash.c
index 613bb97a0..fafbeb86e 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -16292,6 +16292,7 @@ redirtab_copy(struct redirtab *rdtp)
         return start;
 }
 
+#undef funcname
 #undef shellparam
 #undef redirlist
 #undef vartab
@@ -16301,6 +16302,7 @@ globals_var_size(struct datasize ds, struct globals_var *gvp)
         int i;
 
         ds.funcblocksize += sizeof(struct globals_var);
+        ds.funcstringsize += align_len(gvp->funcname);
         ds = argv_size(ds, gvp->shellparam.p);
         ds.funcblocksize = redirtab_size(ds.funcblocksize, gvp->redirlist);
         for (i = 0; i < VTABSIZE; i++)
@@ -16318,6 +16320,9 @@ globals_var_copy(struct globals_var *gvp)
         funcblock = (char *) funcblock + sizeof(struct globals_var);
         memcpy(new, gvp, sizeof(struct globals_var));
 
+        new->funcname = nodeckstrdup(gvp->funcname);
+        SAVE_PTR(new->funcname, xasprintf("funcname '%s'", gvp->funcname ?: "NULL"), FREE);
+
         /* shparam */
         new->shellparam.malloced = 0;
         new->shellparam.p = argv_copy(gvp->shellparam.p);