Fix possible memory leaks, which occurs when constructor components throw errors.

[gitmo/Mouse.git] / xs-src / MouseAccessor.xs

diff --git a/xs-src/MouseAccessor.xs b/xs-src/MouseAccessor.xs
index 4dd16dd..1dad5e6 100644 (file)
--- a/xs-src/MouseAccessor.xs
+++ b/xs-src/MouseAccessor.xs
@@ -1,9 +1,10 @@
 #include "mouse.h"
 
-#define CHECK_INSTANCE(instance) STMT_START{                          \
-        if(!(SvROK(instance) && SvTYPE(SvRV(instance)) == SVt_PVHV)){ \
-            croak("Invalid object instance");                         \
-        }                                                             \
+#define CHECK_INSTANCE(instance) STMT_START{                           \
+        assert(instance);                                              \
+        if(!(SvROK(instance) && SvTYPE(SvRV(instance)) == SVt_PVHV)){  \
+            croak("Invalid object instance: '%"SVf"'", instance);      \
+        }                                                              \
     } STMT_END
 
 
@@ -88,10 +89,12 @@ mouse_push_values(pTHX_ SV* const value, U16 const flags){
             PUSHs(svp ? *svp : &PL_sv_undef);
         }
     }
-    else if(flags & MOUSEf_TC_IS_HASHREF){
+    else{
         HV* hv;
         HE* he;
 
+        assert(flags & MOUSEf_TC_IS_HASHREF);
+
         if(!IsHashRef(value)){
             croak("Mouse-panic: Not a HASH reference");
         }
@@ -132,7 +135,7 @@ mouse_attr_set(pTHX_ SV* const self, MAGIC* const mg, SV* value){
         value = mouse_xa_apply_type_constraint(aTHX_ MOUSE_mg_xa(mg), value, flags);
     }
 
-    set_slot(self, slot, value);
+    value = set_slot(self, slot, value);
 
     if(flags & MOUSEf_ATTR_IS_WEAK_REF){
         weaken_slot(self, slot);
@@ -142,14 +145,22 @@ mouse_attr_set(pTHX_ SV* const self, MAGIC* const mg, SV* value){
         SV* const trigger = mcall0s(MOUSE_mg_attribute(mg), "trigger");
         dSP;
 
+        /* NOTE: triggers can remove value, so
+                 value must be copied here,
+                 revealed by Net::Google::DataAPI (DANJOU).
+         */
+        value = sv_mortalcopy(value);
+
         PUSHMARK(SP);
         EXTEND(SP, 2);
         PUSHs(self);
         PUSHs(value);
 
         PUTBACK;
-        call_sv(trigger, G_VOID | G_DISCARD);
+        call_sv_safe(trigger, G_VOID | G_DISCARD);
         /* need not SPAGAIN */
+
+        assert(SvTYPE(value) != SVTYPEMASK);
     }
 
     PUSH_VALUE(value, flags);
@@ -245,37 +256,6 @@ mouse_simple_accessor_generate(pTHX_ const char* const fq_name, const char* cons
     return xsub;
 }
 
-XS(XS_Mouse_simple_accessor)
-{
-    dVAR; dXSARGS;
-    dMOUSE_self;
-    MAGIC* const mg = (MAGIC*)XSANY.any_ptr;
-    SV* value;
-
-    if(items == 1){ /* reader */
-        value = get_slot(self, MOUSE_mg_slot(mg));
-        if(!value) {
-            if(MOUSE_mg_ptr(mg)){
-                /* the default value must be a SV */
-                assert(MOUSE_mg_len(mg) == HEf_SVKEY);
-                value = (SV*)MOUSE_mg_ptr(mg);
-            }
-            else{
-                value = &PL_sv_undef;
-            }
-        }
-    }
-    else if(items == 2){ /* writer */
-         value = set_slot(self, MOUSE_mg_slot(mg), ST(1));
-    }
-    else {
-        croak("Expected exactly one or two argument for an accessor for '%"SVf"'", MOUSE_mg_slot(mg));
-    }
-
-    ST(0) = value;
-    XSRETURN(1);
-}
-
 XS(XS_Mouse_simple_reader)
 {
     dVAR; dXSARGS;
@@ -288,7 +268,18 @@ XS(XS_Mouse_simple_reader)
     }
 
     value = get_slot(self, MOUSE_mg_slot(mg));
-    ST(0) = value ? value : &PL_sv_undef;
+    if(!value) {
+        if(MOUSE_mg_ptr(mg)){
+            /* the default value must be a SV */
+            assert(MOUSE_mg_len(mg) == HEf_SVKEY);
+            value = (SV*)MOUSE_mg_ptr(mg);
+        }
+        else{
+            value = &PL_sv_undef;
+        }
+    }
+
+    ST(0) = value;
     XSRETURN(1);
 }
 
@@ -341,24 +332,26 @@ XS(XS_Mouse_simple_predicate)
 
 SV*
 mouse_instance_create(pTHX_ HV* const stash) {
+    SV* instance;
     assert(stash);
     assert(SvTYPE(stash) == SVt_PVHV);
-    return sv_bless( newRV_noinc((SV*)newHV()), stash );
+    instance = sv_bless( newRV_noinc((SV*)newHV()), stash );
+    return sv_2mortal(instance);
 }
 
 SV*
 mouse_instance_clone(pTHX_ SV* const instance) {
-    HV* proto;
-    assert(instance);
-
+    SV* proto;
     CHECK_INSTANCE(instance);
-    proto = newHVhv((HV*)SvRV(instance));
-    return sv_bless( newRV_noinc((SV*)proto), SvSTASH(SvRV(instance)) );
+    assert(SvOBJECT(SvRV(instance)));
+
+    proto = newRV_noinc((SV*)newHVhv((HV*)SvRV(instance)));
+    sv_bless(proto, SvSTASH(SvRV(instance)));
+    return sv_2mortal(proto);
 }
 
 bool
 mouse_instance_has_slot(pTHX_ SV* const instance, SV* const slot) {
-    assert(instance);
     assert(slot);
     CHECK_INSTANCE(instance);
     return hv_exists_ent((HV*)SvRV(instance), slot, 0U);
@@ -367,7 +360,6 @@ mouse_instance_has_slot(pTHX_ SV* const instance, SV* const slot) {
 SV*
 mouse_instance_get_slot(pTHX_ SV* const instance, SV* const slot) {
     HE* he;
-    assert(instance);
     assert(slot);
     CHECK_INSTANCE(instance);
     he = hv_fetch_ent((HV*)SvRV(instance), slot, FALSE, 0U);
@@ -378,7 +370,6 @@ SV*
 mouse_instance_set_slot(pTHX_ SV* const instance, SV* const slot, SV* const value) {
     HE* he;
     SV* sv;
-    assert(instance);
     assert(slot);
     assert(value);
     CHECK_INSTANCE(instance);
@@ -400,7 +391,6 @@ mouse_instance_delete_slot(pTHX_ SV* const instance, SV* const slot) {
 void
 mouse_instance_weaken_slot(pTHX_ SV* const instance, SV* const slot) {
     HE* he;
-    assert(instance);
     assert(slot);
     CHECK_INSTANCE(instance);
     he = hv_fetch_ent((HV*)SvRV(instance), slot, FALSE, 0U);
@@ -408,7 +398,7 @@ mouse_instance_weaken_slot(pTHX_ SV* const instance, SV* const slot) {
         sv_rvweaken(HeVAL(he));
     }
 }
-\r
+
 MODULE = Mouse::Meta::Method::Accessor::XS  PACKAGE = Mouse::Meta::Method::Accessor::XS
 
 PROTOTYPES:   DISABLE
@@ -445,7 +435,7 @@ CV*
 _generate_clearer(klass, SV* attr, metaclass)
 CODE:
 {
-    SV* const slot = mcall0s(attr, "name");
+    SV* const slot = mcall0(attr, mouse_name);
     STRLEN len;
     const char* const pv = SvPV_const(slot, len);
     RETVAL = mouse_simple_accessor_generate(aTHX_ NULL, pv, len, XS_Mouse_simple_clearer, NULL, 0);
@@ -457,7 +447,7 @@ CV*
 _generate_predicate(klass, SV* attr, metaclass)
 CODE:
 {
-    SV* const slot = mcall0s(attr, "name");
+    SV* const slot = mcall0(attr, mouse_name);
     STRLEN len;
     const char* const pv = SvPV_const(slot, len);
     RETVAL = mouse_simple_accessor_generate(aTHX_ NULL, pv, len, XS_Mouse_simple_predicate, NULL, 0);