1/*
2 * Copyright (c) 2005, 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25#include "precompiled.hpp"
26#include "classfile/resolutionErrors.hpp"
27#include "memory/resourceArea.hpp"
28#include "oops/oop.inline.hpp"
29#include "runtime/handles.inline.hpp"
30#include "runtime/safepoint.hpp"
31#include "utilities/hashtable.inline.hpp"
32
33// add new entry to the table
34void ResolutionErrorTable::add_entry(int index, unsigned int hash,
35                                     const constantPoolHandle& pool, int cp_index,
36                                     Symbol* error, Symbol* message)
37{
38  assert_locked_or_safepoint(SystemDictionary_lock);
39  assert(!pool.is_null() && error != NULL, "adding NULL obj");
40
41  ResolutionErrorEntry* entry = new_entry(hash, pool(), cp_index, error, message);
42  add_entry(index, entry);
43}
44
45// find entry in the table
46ResolutionErrorEntry* ResolutionErrorTable::find_entry(int index, unsigned int hash,
47                                                       const constantPoolHandle& pool, int cp_index)
48{
49  assert_locked_or_safepoint(SystemDictionary_lock);
50
51  for (ResolutionErrorEntry *error_probe = bucket(index);
52                         error_probe != NULL;
53                         error_probe = error_probe->next()) {
54  if (error_probe->hash() == hash && error_probe->pool() == pool()) {
55      return error_probe;;
56    }
57  }
58  return NULL;
59}
60
61void ResolutionErrorEntry::set_error(Symbol* e) {
62  assert(e != NULL, "must set a value");
63  _error = e;
64  _error->increment_refcount();
65}
66
67void ResolutionErrorEntry::set_message(Symbol* c) {
68  assert(c != NULL, "must set a value");
69  _message = c;
70  _message->increment_refcount();
71}
72
73// create new error entry
74ResolutionErrorEntry* ResolutionErrorTable::new_entry(int hash, ConstantPool* pool,
75                                                      int cp_index, Symbol* error,
76                                                      Symbol* message)
77{
78  ResolutionErrorEntry* entry = (ResolutionErrorEntry*)Hashtable<ConstantPool*, mtClass>::new_entry(hash, pool);
79  entry->set_cp_index(cp_index);
80  entry->set_error(error);
81  entry->set_message(message);
82
83  return entry;
84}
85
86void ResolutionErrorTable::free_entry(ResolutionErrorEntry *entry) {
87  // decrement error refcount
88  assert(entry->error() != NULL, "error should be set");
89  entry->error()->decrement_refcount();
90  entry->message()->decrement_refcount();
91  Hashtable<ConstantPool*, mtClass>::free_entry(entry);
92}
93
94
95// create resolution error table
96ResolutionErrorTable::ResolutionErrorTable(int table_size)
97    : Hashtable<ConstantPool*, mtClass>(table_size, sizeof(ResolutionErrorEntry)) {
98}
99
100// RedefineClasses support - remove matching entry of a
101// constant pool that is going away
102void ResolutionErrorTable::delete_entry(ConstantPool* c) {
103  assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
104  for (int i = 0; i < table_size(); i++) {
105    for (ResolutionErrorEntry** p = bucket_addr(i); *p != NULL; ) {
106      ResolutionErrorEntry* entry = *p;
107      assert(entry->pool() != NULL, "resolution error table is corrupt");
108      if (entry->pool() == c) {
109        *p = entry->next();
110        free_entry(entry);
111      } else {
112        p = entry->next_addr();
113      }
114    }
115  }
116}
117
118
119// Remove unloaded entries from the table
120void ResolutionErrorTable::purge_resolution_errors() {
121  assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
122  for (int i = 0; i < table_size(); i++) {
123    for (ResolutionErrorEntry** p = bucket_addr(i); *p != NULL; ) {
124      ResolutionErrorEntry* entry = *p;
125      assert(entry->pool() != (ConstantPool*)NULL, "resolution error table is corrupt");
126      ConstantPool* pool = entry->pool();
127      assert(pool->pool_holder() != NULL, "Constant pool without a class?");
128      ClassLoaderData* loader_data =
129              pool->pool_holder()->class_loader_data();
130      if (!loader_data->is_unloading()) {
131        p = entry->next_addr();
132      } else {
133        *p = entry->next();
134        free_entry(entry);
135      }
136    }
137  }
138}
139