+/* --- Module setup/teardown ----------------------------------------------- */
+
+#if VMG_THREADSAFE
+
+static I32 vmg_loaded = 0;
+
+/* We must use preexistent global mutexes or we will never be able to destroy
+ * them. */
+# if VMG_HAS_PERL(5, 9, 3)
+# define VMG_LOADED_LOCK MUTEX_LOCK(&PL_my_ctx_mutex)
+# define VMG_LOADED_UNLOCK MUTEX_UNLOCK(&PL_my_ctx_mutex)
+# else
+# define VMG_LOADED_LOCK OP_REFCNT_LOCK
+# define VMG_LOADED_UNLOCK OP_REFCNT_UNLOCK
+# endif
+
+static void vmg_global_teardown_late_locked(pTHX) {
+#define vmg_global_teardown_late_locked() vmg_global_teardown_late_locked(aTHX)
+ MUTEX_DESTROY(&vmg_op_name_init_mutex);
+ MUTEX_DESTROY(&vmg_vtable_refcount_mutex);
+
+ return;
+}
+
+static int vmg_global_teardown_free(pTHX_ SV *sv, MAGIC *mg) {
+ VMG_LOADED_LOCK;
+
+ if (vmg_loaded == 0)
+ vmg_global_teardown_late_locked();
+
+ VMG_LOADED_UNLOCK;
+
+ return 0;
+}
+
+static MGVTBL vmg_global_teardown_vtbl = {
+ 0,
+ 0,
+ 0,
+ 0,
+ vmg_global_teardown_free
+#if MGf_COPY
+ , 0
+#endif
+#if MGf_DUP
+ , 0
+#endif
+#if MGf_LOCAL
+ , 0
+#endif
+};
+
+static signed char vmg_destruct_level(pTHX) {
+#define vmg_destruct_level() vmg_destruct_level(aTHX)
+ signed char lvl;
+
+ lvl = PL_perl_destruct_level;
+
+#ifdef DEBUGGING
+ {
+ const char *s = PerlEnv_getenv("PERL_DESTRUCT_LEVEL");
+ if (s) {
+ int i;
+#if VMG_HAS_PERL(5, 21, 3)
+ if (strEQ(s, "-1")) {
+ i = -1;
+ } else {
+# if VMG_HAS_PERL(5, 21, 10)
+ UV uv;
+ if (Perl_grok_atoUV(s, &uv, NULL) && uv <= INT_MAX)
+ i = (int) uv;
+ else
+ i = 0;
+# else /* VMG_HAS_PERL(5, 21, 3) && !VMG_HAS_PERL(5, 21, 10) */
+ i = Perl_grok_atou(s, NULL);
+# endif
+ }
+#else /* !VMG_HAS_PERL(5, 21, 3) */
+ i = atoi(s);
+#endif
+ if (lvl < i)
+ lvl = i;
+ }
+ }
+#endif
+
+ return lvl;
+}
+
+#endif /* VMG_THREADSAFE */
+
+static void vmg_teardown(pTHX_ void *param) {
+ dMY_CXT;
+
+#if VMG_THREADSAFE
+ VMG_LOADED_LOCK;
+
+ if (vmg_loaded == 1) {
+ vmg_loaded = 0;
+ if (vmg_destruct_level() == 0) {
+ vmg_global_teardown_late_locked();
+ } else {
+ if (!PL_strtab)
+ PL_strtab = newHV();
+ vmg_sv_magicext((SV *) PL_strtab, NULL, &vmg_global_teardown_vtbl, NULL, 0);
+ }
+ } else {
+ VMG_ASSERT(vmg_loaded > 1);
+ --vmg_loaded;
+ }
+
+ VMG_LOADED_UNLOCK;
+#endif
+
+ if (MY_CXT.depth == 0 && MY_CXT.freed_tokens) {
+ vmg_magic_chain_free(MY_CXT.freed_tokens, NULL);
+ MY_CXT.freed_tokens = NULL;
+ }
+
+ return;
+}
+
+static void vmg_setup(pTHX) {
+#define vmg_setup() vmg_setup(aTHX)
+ HV *stash;
+ int c;
+ MY_CXT_INIT;
+
+#if VMG_THREADSAFE
+ VMG_LOADED_LOCK;
+
+ if (vmg_loaded == 0) {
+ MUTEX_INIT(&vmg_vtable_refcount_mutex);
+ MUTEX_INIT(&vmg_op_name_init_mutex);
+ vmg_loaded = 1;
+ } else {
+ VMG_ASSERT(vmg_loaded > 0);
+ ++vmg_loaded;
+ }
+
+ VMG_LOADED_UNLOCK;
+#endif
+
+ for (c = OPc_NULL; c < OPc_MAX; ++c)
+ MY_CXT.b__op_stashes[c] = NULL;
+
+ MY_CXT.depth = 0;
+ MY_CXT.freed_tokens = NULL;
+
+#if VMG_PROPAGATE_ERRSV_NEEDS_TRAMPOLINE
+ vmg_trampoline_init(&MY_CXT.propagate_errsv, vmg_pp_propagate_errsv);
+#endif
+#if VMG_RESET_RMG_NEEDS_TRAMPOLINE
+ vmg_trampoline_init(&MY_CXT.reset_rmg, vmg_pp_reset_rmg);
+#endif
+
+ stash = gv_stashpv(__PACKAGE__, 1);
+ newCONSTSUB(stash, "MGf_COPY", newSVuv(MGf_COPY));
+ newCONSTSUB(stash, "MGf_DUP", newSVuv(MGf_DUP));
+ newCONSTSUB(stash, "MGf_LOCAL", newSVuv(MGf_LOCAL));
+ newCONSTSUB(stash, "VMG_UVAR", newSVuv(VMG_UVAR));
+ newCONSTSUB(stash, "VMG_COMPAT_SCALAR_LENGTH_NOLEN",
+ newSVuv(VMG_COMPAT_SCALAR_LENGTH_NOLEN));
+ newCONSTSUB(stash, "VMG_COMPAT_SCALAR_NOLEN",
+ newSVuv(VMG_COMPAT_SCALAR_NOLEN));
+ newCONSTSUB(stash, "VMG_COMPAT_ARRAY_PUSH_NOLEN",
+ newSVuv(VMG_COMPAT_ARRAY_PUSH_NOLEN));
+ newCONSTSUB(stash, "VMG_COMPAT_ARRAY_PUSH_NOLEN_VOID",
+ newSVuv(VMG_COMPAT_ARRAY_PUSH_NOLEN_VOID));
+ newCONSTSUB(stash, "VMG_COMPAT_ARRAY_UNSHIFT_NOLEN_VOID",
+ newSVuv(VMG_COMPAT_ARRAY_UNSHIFT_NOLEN_VOID));
+ newCONSTSUB(stash, "VMG_COMPAT_ARRAY_UNDEF_CLEAR",
+ newSVuv(VMG_COMPAT_ARRAY_UNDEF_CLEAR));
+ newCONSTSUB(stash, "VMG_COMPAT_HASH_DELETE_NOUVAR_VOID",
+ newSVuv(VMG_COMPAT_HASH_DELETE_NOUVAR_VOID));
+ newCONSTSUB(stash, "VMG_COMPAT_CODE_COPY_CLONE",
+ newSVuv(VMG_COMPAT_CODE_COPY_CLONE));
+ newCONSTSUB(stash, "VMG_COMPAT_GLOB_GET", newSVuv(VMG_COMPAT_GLOB_GET));
+ newCONSTSUB(stash, "VMG_PERL_PATCHLEVEL", newSVuv(VMG_PERL_PATCHLEVEL));
+ newCONSTSUB(stash, "VMG_THREADSAFE", newSVuv(VMG_THREADSAFE));
+ newCONSTSUB(stash, "VMG_FORKSAFE", newSVuv(VMG_FORKSAFE));
+ newCONSTSUB(stash, "VMG_OP_INFO_NAME", newSVuv(VMG_OP_INFO_NAME));
+ newCONSTSUB(stash, "VMG_OP_INFO_OBJECT", newSVuv(VMG_OP_INFO_OBJECT));
+
+ call_atexit(vmg_teardown, NULL);
+
+ return;
+}
+