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src/hotspot/share/prims/jvmtiRedefineClasses.cpp
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@@ -681,10 +681,17 @@
_operands_index_map_p = NULL;
_operands_cur_length = 0;
_operands_index_map_count = 0;
} // end finalize_operands_merge()
+// Symbol* comparator for qsort
+// The caller must have an active ResourceMark.
+static int symcmp(const void* a, const void* b) {
+ char* astr = (*(Symbol**)a)->as_C_string();
+ char* bstr = (*(Symbol**)b)->as_C_string();
+ return strcmp(astr, bstr);
+}
jvmtiError VM_RedefineClasses::compare_and_normalize_class_versions(
InstanceKlass* the_class,
InstanceKlass* scratch_class) {
int i;
@@ -723,10 +730,104 @@
if (the_class->is_in_error_state()) {
// TBD #5057930: special error code is needed in 1.6
return JVMTI_ERROR_INVALID_CLASS;
}
+ // Check whether the class NestHost attribute has been changed.
+ {
+ Thread* thread = Thread::current();
+ ResourceMark rm(thread);
+ JvmtiThreadState *state = JvmtiThreadState::state_for((JavaThread*)thread);
+ RedefineVerifyMark rvm(the_class, scratch_class, state);
+ u2 the_nest_host_idx = the_class->nest_host_index();
+ u2 scr_nest_host_idx = scratch_class->nest_host_index();
+
+ if (the_nest_host_idx != 0 && scr_nest_host_idx != 0) {
+ Symbol* the_sym = the_class->constants()->klass_name_at(the_nest_host_idx);
+ Symbol* scr_sym = scratch_class->constants()->klass_name_at(scr_nest_host_idx);
+ if (the_sym != scr_sym) {
+ log_trace(redefine, class, nestmates)
+ ("redefined class %s attribute change error: NestHost class: %s replaced with: %s",
+ the_class->external_name(), the_sym->as_C_string(), scr_sym->as_C_string());
+ return JVMTI_ERROR_UNSUPPORTED_REDEFINITION_CLASS_ATTRIBUTE_CHANGED;
+ }
+ } else if ((the_nest_host_idx == 0) ^ (scr_nest_host_idx == 0)) {
+ const char* action_str = (the_nest_host_idx != 0) ? "removed" : "added";
+ log_trace(redefine, class, nestmates)
+ ("redefined class %s attribute change error: NestHost attribute %s",
+ the_class->external_name(), action_str);
+ return JVMTI_ERROR_UNSUPPORTED_REDEFINITION_CLASS_ATTRIBUTE_CHANGED;
+ }
+
+ // Check whether the class NestMembers attribute has been changed.
+ Array<u2>* the_nest_members = the_class->nest_members();
+ Array<u2>* scr_nest_members = scratch_class->nest_members();
+ bool the_members_exists = the_nest_members != Universe::the_empty_short_array();
+ bool scr_members_exists = scr_nest_members != Universe::the_empty_short_array();
+
+ int members_len = the_nest_members->length();
+ if (the_members_exists && scr_members_exists) {
+ if (members_len != scr_nest_members->length()) {
+ log_trace(redefine, class, nestmates)
+ ("redefined class %s attribute change error: NestMember len=%d changed to len=%d",
+ the_class->external_name(), members_len, scr_nest_members->length());
+ return JVMTI_ERROR_UNSUPPORTED_REDEFINITION_CLASS_ATTRIBUTE_CHANGED;
+ }
+
+ // The order of entries in the NestMembers array is not specified so we
+ // have to explicitly check for the same contents. We do this by copying
+ // the referenced symbols into their own arrays, sorting them and then
+ // comparing each element pair.
+
+ Symbol** the_syms = NEW_RESOURCE_ARRAY_RETURN_NULL(Symbol*, members_len);
+ Symbol** scr_syms = NEW_RESOURCE_ARRAY_RETURN_NULL(Symbol*, members_len);
+
+ if (the_syms == NULL || scr_syms == NULL) {
+ return JVMTI_ERROR_OUT_OF_MEMORY;
+ }
+
+ for (int i = 0; i < members_len; i++) {
+ int the_cp_index = the_nest_members->at(i);
+ int scr_cp_index = scr_nest_members->at(i);
+ the_syms[i] = the_class->constants()->klass_name_at(the_cp_index);
+ scr_syms[i] = scratch_class->constants()->klass_name_at(scr_cp_index);
+ }
+
+ qsort(the_syms, members_len, sizeof(Symbol*), symcmp);
+ qsort(scr_syms, members_len, sizeof(Symbol*), symcmp);
+
+ for (int i = 0; i < members_len; i++) {
+ if (the_syms[i] != scr_syms[i]) {
+ log_trace(redefine, class, nestmates)
+ ("redefined class %s attribute change error: NestMembers[%d]: %s changed to %s",
+ the_class->external_name(), i, the_syms[i]->as_C_string(), scr_syms[i]->as_C_string());
+ return JVMTI_ERROR_UNSUPPORTED_REDEFINITION_CLASS_ATTRIBUTE_CHANGED;
+ }
+ }
+ /*
+ for (int i = 0; i < members_len; i++) {
+ int the_cp_index = the_nest_members->at(i);
+ int scr_cp_index = scr_nest_members->at(i);
+ Symbol* the_sym = the_class->constants()->klass_name_at(the_cp_index);
+ Symbol* scr_sym = scratch_class->constants()->klass_name_at(scr_cp_index);
+ if (the_sym != scr_sym) {
+ log_trace(redefine, class, nestmates)
+ ("redefined class %s attribute change error: NestMembers[%d]: %s changed to %s",
+ the_class->external_name(), i, the_sym->as_C_string(), scr_sym->as_C_string());
+ return JVMTI_ERROR_UNSUPPORTED_REDEFINITION_CLASS_ATTRIBUTE_CHANGED;
+ }
+ }
+ */
+ } else if (the_members_exists ^ scr_members_exists) {
+ const char* action_str = (the_members_exists) ? "removed" : "added";
+ log_trace(redefine, class, nestmates)
+ ("redefined class %s attribute change error: NestMembers attribute %s",
+ the_class->external_name(), action_str);
+ return JVMTI_ERROR_UNSUPPORTED_REDEFINITION_CLASS_ATTRIBUTE_CHANGED;
+ }
+ }
+
// Check whether class modifiers are the same.
jushort old_flags = (jushort) the_class->access_flags().get_flags();
jushort new_flags = (jushort) scratch_class->access_flags().get_flags();
if (old_flags != new_flags) {
return JVMTI_ERROR_UNSUPPORTED_REDEFINITION_CLASS_MODIFIERS_CHANGED;
@@ -1596,10 +1697,16 @@
// Rewrite constant pool references in klass scratch_class.
bool VM_RedefineClasses::rewrite_cp_refs(InstanceKlass* scratch_class,
TRAPS) {
+ // rewrite constant pool references in the nest attributes:
+ if (!rewrite_cp_refs_in_nest_attributes(scratch_class)) {
+ // propagate failure back to caller
+ return false;
+ }
+
// rewrite constant pool references in the methods:
if (!rewrite_cp_refs_in_methods(scratch_class, THREAD)) {
// propagate failure back to caller
return false;
}
@@ -1678,10 +1785,26 @@
}
return true;
} // end rewrite_cp_refs()
+// Rewrite constant pool references in the NestHost and NestMembers attributes.
+bool VM_RedefineClasses::rewrite_cp_refs_in_nest_attributes(
+ InstanceKlass* scratch_class) {
+
+ u2 cp_index = scratch_class->nest_host_index();
+ if (cp_index != 0) {
+ scratch_class->set_nest_host_index(find_new_index(cp_index));
+ }
+ Array<u2>* nest_members = scratch_class->nest_members();
+ for (int i = 0; i < nest_members->length(); i++) {
+ u2 cp_index = nest_members->at(i);
+ nest_members->at_put(i, find_new_index(cp_index));
+ }
+ return true;
+}
+
// Rewrite constant pool references in the methods.
bool VM_RedefineClasses::rewrite_cp_refs_in_methods(
InstanceKlass* scratch_class, TRAPS) {
Array<Method*>* methods = scratch_class->methods();
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