1/*
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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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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_DICTIONARY_HPP
26#define SHARE_CLASSFILE_DICTIONARY_HPP
27
28#include "classfile/protectionDomainCache.hpp"
29#include "classfile/systemDictionary.hpp"
30#include "oops/instanceKlass.hpp"
31#include "oops/oop.hpp"
32#include "utilities/hashtable.hpp"
33#include "utilities/ostream.hpp"
34
35class DictionaryEntry;
36class BoolObjectClosure;
37
38//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
39// The data structure for the class loader data dictionaries.
40
41class Dictionary : public Hashtable<InstanceKlass*, mtClass> {
42 friend class VMStructs;
43
44 static bool _some_dictionary_needs_resizing;
45 bool _resizable;
46 bool _needs_resizing;
47 void check_if_needs_resize();
48
49 ClassLoaderData* _loader_data; // backpointer to owning loader
50 ClassLoaderData* loader_data() const { return _loader_data; }
51
52 DictionaryEntry* get_entry(int index, unsigned int hash, Symbol* name);
53
54public:
55 Dictionary(ClassLoaderData* loader_data, int table_size, bool resizable = false);
56 Dictionary(ClassLoaderData* loader_data, int table_size, HashtableBucket<mtClass>* t, int number_of_entries, bool resizable = false);
57 ~Dictionary();
58
59 static bool does_any_dictionary_needs_resizing();
60 bool resize_if_needed();
61
62 void add_klass(unsigned int hash, Symbol* class_name, InstanceKlass* obj);
63
64 InstanceKlass* find_class(int index, unsigned int hash, Symbol* name);
65
66 void classes_do(void f(InstanceKlass*));
67 void classes_do(void f(InstanceKlass*, TRAPS), TRAPS);
68 void all_entries_do(KlassClosure* closure);
69 void classes_do(MetaspaceClosure* it);
70
71 void clean_cached_protection_domains();
72
73 // Protection domains
74 InstanceKlass* find(unsigned int hash, Symbol* name, Handle protection_domain);
75 bool is_valid_protection_domain(unsigned int hash,
76 Symbol* name,
77 Handle protection_domain);
78 void add_protection_domain(int index, unsigned int hash,
79 InstanceKlass* klass,
80 Handle protection_domain, TRAPS);
81
82 void print_on(outputStream* st) const;
83 void verify();
84
85 private:
86 DictionaryEntry* new_entry(unsigned int hash, InstanceKlass* klass);
87
88 DictionaryEntry* bucket(int i) const {
89 return (DictionaryEntry*)Hashtable<InstanceKlass*, mtClass>::bucket(i);
90 }
91
92 // The following method is not MT-safe and must be done under lock.
93 DictionaryEntry** bucket_addr(int i) {
94 return (DictionaryEntry**)Hashtable<InstanceKlass*, mtClass>::bucket_addr(i);
95 }
96
97 void add_entry(int index, DictionaryEntry* new_entry) {
98 Hashtable<InstanceKlass*, mtClass>::add_entry(index, (HashtableEntry<InstanceKlass*, mtClass>*)new_entry);
99 }
100
101 void unlink_entry(DictionaryEntry* entry) {
102 Hashtable<InstanceKlass*, mtClass>::unlink_entry((HashtableEntry<InstanceKlass*, mtClass>*)entry);
103 }
104
105 void free_entry(DictionaryEntry* entry);
106};
107
108// An entry in the class loader data dictionaries, this describes a class as
109// { InstanceKlass*, protection_domain }.
110
111class DictionaryEntry : public HashtableEntry<InstanceKlass*, mtClass> {
112 friend class VMStructs;
113 private:
114 // Contains the set of approved protection domains that can access
115 // this dictionary entry.
116 //
117 // This protection domain set is a set of tuples:
118 //
119 // (InstanceKlass C, initiating class loader ICL, Protection Domain PD)
120 //
121 // [Note that C.protection_domain(), which is stored in the java.lang.Class
122 // mirror of C, is NOT the same as PD]
123 //
124 // If such an entry (C, ICL, PD) exists in the table, it means that
125 // it is okay for a class Foo to reference C, where
126 //
127 // Foo.protection_domain() == PD, and
128 // Foo's defining class loader == ICL
129 //
130 // The usage of the PD set can be seen in SystemDictionary::validate_protection_domain()
131 // It is essentially a cache to avoid repeated Java up-calls to
132 // ClassLoader.checkPackageAccess().
133 //
134 ProtectionDomainEntry* volatile _pd_set;
135
136 public:
137 // Tells whether a protection is in the approved set.
138 bool contains_protection_domain(oop protection_domain) const;
139 // Adds a protection domain to the approved set.
140 void add_protection_domain(Dictionary* dict, Handle protection_domain);
141
142 InstanceKlass* instance_klass() const { return literal(); }
143 InstanceKlass** klass_addr() { return (InstanceKlass**)literal_addr(); }
144
145 DictionaryEntry* next() const {
146 return (DictionaryEntry*)HashtableEntry<InstanceKlass*, mtClass>::next();
147 }
148
149 DictionaryEntry** next_addr() {
150 return (DictionaryEntry**)HashtableEntry<InstanceKlass*, mtClass>::next_addr();
151 }
152
153 ProtectionDomainEntry* pd_set() const { return _pd_set; }
154 void set_pd_set(ProtectionDomainEntry* new_head) { _pd_set = new_head; }
155
156 // Tells whether the initiating class' protection domain can access the klass in this entry
157 bool is_valid_protection_domain(Handle protection_domain) {
158 if (!ProtectionDomainVerification) return true;
159 if (!SystemDictionary::has_checkPackageAccess()) return true;
160
161 return protection_domain() == NULL
162 ? true
163 : contains_protection_domain(protection_domain());
164 }
165
166 void verify_protection_domain_set();
167
168 bool equals(const Symbol* class_name) const {
169 InstanceKlass* klass = (InstanceKlass*)literal();
170 return (klass->name() == class_name);
171 }
172
173 void print_count(outputStream *st);
174 void verify();
175};
176
177// Entry in a SymbolPropertyTable, mapping a single Symbol*
178// to a managed and an unmanaged pointer.
179class SymbolPropertyEntry : public HashtableEntry<Symbol*, mtSymbol> {
180 friend class VMStructs;
181 private:
182 intptr_t _symbol_mode; // secondary key
183 Method* _method;
184 oop _method_type;
185
186 public:
187 Symbol* symbol() const { return literal(); }
188
189 intptr_t symbol_mode() const { return _symbol_mode; }
190 void set_symbol_mode(intptr_t m) { _symbol_mode = m; }
191
192 Method* method() const { return _method; }
193 void set_method(Method* p) { _method = p; }
194
195 oop method_type() const { return _method_type; }
196 oop* method_type_addr() { return &_method_type; }
197 void set_method_type(oop p) { _method_type = p; }
198
199 SymbolPropertyEntry* next() const {
200 return (SymbolPropertyEntry*)HashtableEntry<Symbol*, mtSymbol>::next();
201 }
202
203 SymbolPropertyEntry** next_addr() {
204 return (SymbolPropertyEntry**)HashtableEntry<Symbol*, mtSymbol>::next_addr();
205 }
206
207 void print_entry(outputStream* st) const {
208 symbol()->print_value_on(st);
209 st->print("/mode=" INTX_FORMAT, symbol_mode());
210 st->print(" -> ");
211 bool printed = false;
212 if (method() != NULL) {
213 method()->print_value_on(st);
214 printed = true;
215 }
216 if (method_type() != NULL) {
217 if (printed) st->print(" and ");
218 st->print(INTPTR_FORMAT, p2i((void *)method_type()));
219 printed = true;
220 }
221 st->print_cr(printed ? "" : "(empty)");
222 }
223};
224
225// A system-internal mapping of symbols to pointers, both managed
226// and unmanaged. Used to record the auto-generation of each method
227// MethodHandle.invoke(S)T, for all signatures (S)T.
228class SymbolPropertyTable : public Hashtable<Symbol*, mtSymbol> {
229 friend class VMStructs;
230private:
231 // The following method is not MT-safe and must be done under lock.
232 SymbolPropertyEntry** bucket_addr(int i) {
233 return (SymbolPropertyEntry**) Hashtable<Symbol*, mtSymbol>::bucket_addr(i);
234 }
235
236 void add_entry(int index, SymbolPropertyEntry* new_entry) {
237 ShouldNotReachHere();
238 }
239 void set_entry(int index, SymbolPropertyEntry* new_entry) {
240 ShouldNotReachHere();
241 }
242
243 SymbolPropertyEntry* new_entry(unsigned int hash, Symbol* symbol, intptr_t symbol_mode) {
244 SymbolPropertyEntry* entry = (SymbolPropertyEntry*) Hashtable<Symbol*, mtSymbol>::new_entry(hash, symbol);
245 // Hashtable with Symbol* literal must increment and decrement refcount.
246 symbol->increment_refcount();
247 entry->set_symbol_mode(symbol_mode);
248 entry->set_method(NULL);
249 entry->set_method_type(NULL);
250 return entry;
251 }
252
253public:
254 SymbolPropertyTable(int table_size);
255 SymbolPropertyTable(int table_size, HashtableBucket<mtSymbol>* t, int number_of_entries);
256
257 void free_entry(SymbolPropertyEntry* entry) {
258 // decrement Symbol refcount here because hashtable doesn't.
259 entry->literal()->decrement_refcount();
260 Hashtable<Symbol*, mtSymbol>::free_entry(entry);
261 }
262
263 unsigned int compute_hash(Symbol* sym, intptr_t symbol_mode) {
264 // Use the regular identity_hash.
265 return Hashtable<Symbol*, mtSymbol>::compute_hash(sym) ^ symbol_mode;
266 }
267
268 int index_for(Symbol* name, intptr_t symbol_mode) {
269 return hash_to_index(compute_hash(name, symbol_mode));
270 }
271
272 // need not be locked; no state change
273 SymbolPropertyEntry* find_entry(int index, unsigned int hash, Symbol* name, intptr_t name_mode);
274
275 // must be done under SystemDictionary_lock
276 SymbolPropertyEntry* add_entry(int index, unsigned int hash, Symbol* name, intptr_t name_mode);
277
278 // GC support
279 void oops_do(OopClosure* f);
280
281 void methods_do(void f(Method*));
282
283 void verify();
284
285 SymbolPropertyEntry* bucket(int i) {
286 return (SymbolPropertyEntry*) Hashtable<Symbol*, mtSymbol>::bucket(i);
287 }
288};
289#endif // SHARE_CLASSFILE_DICTIONARY_HPP
290