Protect the access to lt_op_map by a mutex

diff --git a/Types.xs b/Types.xs
index a6df2b9f8f2e08e40cd09ef04e5e508033c9efb0..0b5b3f5fd1c97f2581f7f2c775bf00d836e2b547 100644 (file)
--- a/Types.xs
+++ b/Types.xs
@@ -67,6 +67,10 @@ STATIC SV *lt_hint(pTHX) {
 
 STATIC ptable *lt_op_map = NULL;
 
+#ifdef USE_ITHREADS
+STATIC perl_mutex lt_op_map_mutex;
+#endif
+
 typedef struct {
  SV *orig_pkg;
  SV *type_pkg;
@@ -75,9 +79,13 @@ typedef struct {
 } lt_op_info;
 
 STATIC void lt_map_store(const OP *o, SV *orig_pkg, SV *type_pkg, SV *type_meth, OP *(*pp_padsv)(pTHX)) {
- lt_op_info *oi = ptable_fetch(lt_op_map, o);
+ lt_op_info *oi;
+
+#ifdef USE_ITHREADS
+ MUTEX_LOCK(&lt_op_map_mutex);
+#endif
 
- if (!oi) {
+ if (!(oi = ptable_fetch(lt_op_map, o))) {
   oi = PerlMemShared_malloc(sizeof *oi);
   ptable_store(lt_op_map, o, oi);
  }
@@ -86,14 +94,30 @@ STATIC void lt_map_store(const OP *o, SV *orig_pkg, SV *type_pkg, SV *type_meth,
  oi->type_pkg  = type_pkg;
  oi->type_meth = type_meth;
  oi->pp_padsv  = pp_padsv;
+
+#ifdef USE_ITHREADS
+ MUTEX_UNLOCK(&lt_op_map_mutex);
+#endif
 }
 
-STATIC const lt_op_info *lt_map_fetch(const OP *o) {
- const lt_op_info *oi;
+STATIC const lt_op_info *lt_map_fetch(const OP *o, lt_op_info *oi) {
+ const lt_op_info *val;
 
- oi = ptable_fetch(lt_op_map, o);
+#ifdef USE_ITHREADS
+ MUTEX_LOCK(&lt_op_map_mutex);
+#endif
+
+ val = ptable_fetch(lt_op_map, o);
+ if (val) {
+  *oi = *val;
+  val = oi;
+ }
 
- return oi;
+#ifdef USE_ITHREADS
+ MUTEX_UNLOCK(&lt_op_map_mutex);
+#endif
+
+ return val;
 }
 
 /* --- Hooks --------------------------------------------------------------- */
@@ -101,9 +125,9 @@ STATIC const lt_op_info *lt_map_fetch(const OP *o) {
 /* ... Our pp_padsv ........................................................ */
 
 STATIC OP *lt_pp_padsv(pTHX) {
- const lt_op_info *oi;
+ lt_op_info oi;
 
- if ((PL_op->op_private & OPpLVAL_INTRO) && (oi = lt_map_fetch(PL_op))) {
+ if ((PL_op->op_private & OPpLVAL_INTRO) && lt_map_fetch(PL_op, &oi)) {
   PADOFFSET targ = PL_op->op_targ;
   SV *sv         = PAD_SVl(targ);
 
@@ -116,12 +140,12 @@ STATIC OP *lt_pp_padsv(pTHX) {
 
    PUSHMARK(SP);
    EXTEND(SP, 3);
-   PUSHs(oi->type_pkg);
+   PUSHs(oi.type_pkg);
    PUSHs(sv);
-   PUSHs(oi->orig_pkg);
+   PUSHs(oi.orig_pkg);
    PUTBACK;
 
-   items = call_sv(oi->type_meth, G_ARRAY | G_METHOD);
+   items = call_sv(oi.type_meth, G_ARRAY | G_METHOD);
 
    SPAGAIN;
    switch (items) {
@@ -139,7 +163,7 @@ STATIC OP *lt_pp_padsv(pTHX) {
    LEAVE;
   }
 
-  return CALL_FPTR(oi->pp_padsv)(aTHX);
+  return CALL_FPTR(oi.pp_padsv)(aTHX);
  }
 
  return CALL_FPTR(PL_ppaddr[OP_PADSV])(aTHX);
@@ -279,6 +303,9 @@ BOOT:
 {                                    
  if (!lt_initialized++) {
   lt_op_map = ptable_new();
+#ifdef USE_ITHREADS
+  MUTEX_INIT(&lt_op_map_mutex);
+#endif
 
   lt_default_meth = newSVpvn("TYPEDSCALAR", 11);
   SvREADONLY_on(lt_default_meth);