1/*
2 * Copyright (c) 2003, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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7 * published by the Free Software Foundation.
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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).
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24
25#ifndef SHARE_CLASSFILE_LOADERCONSTRAINTS_HPP
26#define SHARE_CLASSFILE_LOADERCONSTRAINTS_HPP
27
28#include "classfile/placeholders.hpp"
29#include "utilities/hashtable.hpp"
30
31class ClassLoaderData;
32class LoaderConstraintEntry;
33class Symbol;
34
35class LoaderConstraintTable : public Hashtable<InstanceKlass*, mtClass> {
36
37private:
38 LoaderConstraintEntry** find_loader_constraint(Symbol* name,
39 Handle loader);
40
41public:
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) const {
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 void print_on(outputStream* st) const;
83};
84
85class LoaderConstraintEntry : public HashtableEntry<InstanceKlass*, mtClass> {
86private:
87 Symbol* _name; // class name
88 int _num_loaders;
89 int _max_loaders;
90 // Loader constraints enforce correct linking behavior.
91 // Thus, it really operates on ClassLoaderData which represents linking domain,
92 // not class loaders.
93 ClassLoaderData** _loaders; // initiating loaders
94
95public:
96
97 InstanceKlass* klass() { return literal(); }
98 InstanceKlass** klass_addr() { return literal_addr(); }
99 void set_klass(InstanceKlass* k) { set_literal(k); }
100
101 LoaderConstraintEntry* next() {
102 return (LoaderConstraintEntry*)HashtableEntry<InstanceKlass*, mtClass>::next();
103 }
104
105 LoaderConstraintEntry** next_addr() {
106 return (LoaderConstraintEntry**)HashtableEntry<InstanceKlass*, mtClass>::next_addr();
107 }
108 void set_next(LoaderConstraintEntry* next) {
109 HashtableEntry<InstanceKlass*, mtClass>::set_next(next);
110 }
111
112 Symbol* name() { return _name; }
113 void set_name(Symbol* name) {
114 _name = name;
115 if (name != NULL) name->increment_refcount();
116 }
117
118 int num_loaders() { return _num_loaders; }
119 void set_num_loaders(int i) { _num_loaders = i; }
120
121 int max_loaders() { return _max_loaders; }
122 void set_max_loaders(int i) { _max_loaders = i; }
123
124 ClassLoaderData** loaders() { return _loaders; }
125 void set_loaders(ClassLoaderData** loaders) { _loaders = loaders; }
126
127 ClassLoaderData* loader_data(int i) { return _loaders[i]; }
128 void set_loader_data(int i, ClassLoaderData* p) { _loaders[i] = p; }
129 // convenience
130 void set_loader(int i, oop p);
131};
132
133#endif // SHARE_CLASSFILE_LOADERCONSTRAINTS_HPP
134