1 /*
2 * Copyright (c) 2003, 2017, 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 #ifndef SHARE_VM_CLASSFILE_LOADERCONSTRAINTS_HPP
26 #define SHARE_VM_CLASSFILE_LOADERCONSTRAINTS_HPP
27
28 #include "classfile/placeholders.hpp"
29 #include "utilities/hashtable.hpp"
30
31 class ClassLoaderData;
32 class LoaderConstraintEntry;
33 class Symbol;
34
35 class LoaderConstraintTable : public Hashtable<InstanceKlass*, mtClass> {
36
37 private:
38 LoaderConstraintEntry** find_loader_constraint(Symbol* name,
39 Handle loader);
40
41 public:
42
43 LoaderConstraintTable(int table_size);
44
45 LoaderConstraintEntry* new_entry(unsigned int hash, Symbol* name,
46 InstanceKlass* klass, int num_loaders,
47 int max_loaders);
48 void free_entry(LoaderConstraintEntry *entry);
49
50 LoaderConstraintEntry* bucket(int i) {
51 return (LoaderConstraintEntry*)Hashtable<InstanceKlass*, mtClass>::bucket(i);
52 }
53
54 LoaderConstraintEntry** bucket_addr(int i) {
55 return (LoaderConstraintEntry**)Hashtable<InstanceKlass*, mtClass>::bucket_addr(i);
56 }
57
58 // Check class loader constraints
59 bool add_entry(Symbol* name, InstanceKlass* klass1, Handle loader1,
60 InstanceKlass* klass2, Handle loader2);
61
62 // Note: The main entry point for this module is via SystemDictionary.
63 // SystemDictionary::check_signature_loaders(Symbol* signature,
64 // Handle loader1, Handle loader2,
65 // bool is_method, TRAPS)
66
67 InstanceKlass* find_constrained_klass(Symbol* name, Handle loader);
68
69 // Class loader constraints
70
71 void ensure_loader_constraint_capacity(LoaderConstraintEntry *p, int nfree);
72 void extend_loader_constraint(LoaderConstraintEntry* p, Handle loader,
73 InstanceKlass* klass);
74 void merge_loader_constraints(LoaderConstraintEntry** pp1,
75 LoaderConstraintEntry** pp2, InstanceKlass* klass);
76
77 bool check_or_update(InstanceKlass* k, Handle loader, Symbol* name);
78
79 void purge_loader_constraints();
80
81 void verify(PlaceholderTable* placeholders);
82 #ifndef PRODUCT
83 void print();
84 #endif
85 };
86
87 class LoaderConstraintEntry : public HashtableEntry<InstanceKlass*, mtClass> {
88 private:
89 Symbol* _name; // class name
90 int _num_loaders;
91 int _max_loaders;
92 // Loader constraints enforce correct linking behavior.
93 // Thus, it really operates on ClassLoaderData which represents linking domain,
94 // not class loaders.
95 ClassLoaderData** _loaders; // initiating loaders
96
97 public:
98
99 InstanceKlass* klass() { return literal(); }
100 InstanceKlass** klass_addr() { return literal_addr(); }
101 void set_klass(InstanceKlass* k) { set_literal(k); }
102
103 LoaderConstraintEntry* next() {
104 return (LoaderConstraintEntry*)HashtableEntry<InstanceKlass*, mtClass>::next();
105 }
106
107 LoaderConstraintEntry** next_addr() {
108 return (LoaderConstraintEntry**)HashtableEntry<InstanceKlass*, mtClass>::next_addr();
109 }
110 void set_next(LoaderConstraintEntry* next) {
111 HashtableEntry<InstanceKlass*, mtClass>::set_next(next);
112 }
113
114 Symbol* name() { return _name; }
115 void set_name(Symbol* name) {
116 _name = name;
117 if (name != NULL) name->increment_refcount();
118 }
119
120 int num_loaders() { return _num_loaders; }
121 void set_num_loaders(int i) { _num_loaders = i; }
122
123 int max_loaders() { return _max_loaders; }
124 void set_max_loaders(int i) { _max_loaders = i; }
125
126 ClassLoaderData** loaders() { return _loaders; }
127 void set_loaders(ClassLoaderData** loaders) { _loaders = loaders; }
128
129 ClassLoaderData* loader_data(int i) { return _loaders[i]; }
130 void set_loader_data(int i, ClassLoaderData* p) { _loaders[i] = p; }
131 // convenience
132 void set_loader(int i, oop p);
133 };
134
135 #endif // SHARE_VM_CLASSFILE_LOADERCONSTRAINTS_HPP