1 /*
2 * Copyright (c) 2003, 2009, 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 class DictionaryEntry;
26
27 //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
28 // The data structure for the system dictionary (and the shared system
29 // dictionary).
30
31 class Dictionary : public TwoOopHashtable {
32 friend class VMStructs;
33 private:
34 // current iteration index.
35 static int _current_class_index;
36 // pointer to the current hash table entry.
37 static DictionaryEntry* _current_class_entry;
38
39 DictionaryEntry* get_entry(int index, unsigned int hash,
40 symbolHandle name, Handle loader);
41
42 DictionaryEntry* bucket(int i) {
43 return (DictionaryEntry*)Hashtable::bucket(i);
44 }
45
46 // The following method is not MT-safe and must be done under lock.
47 DictionaryEntry** bucket_addr(int i) {
48 return (DictionaryEntry**)Hashtable::bucket_addr(i);
49 }
50
51 void add_entry(int index, DictionaryEntry* new_entry) {
52 Hashtable::add_entry(index, (HashtableEntry*)new_entry);
53 }
54
55
56 public:
57 Dictionary(int table_size);
58 Dictionary(int table_size, HashtableBucket* t, int number_of_entries);
59
60 DictionaryEntry* new_entry(unsigned int hash, klassOop klass, oop loader);
61
62 DictionaryEntry* new_entry();
63
64 void free_entry(DictionaryEntry* entry);
65
66 void add_klass(symbolHandle class_name, Handle class_loader,KlassHandle obj);
67
68 klassOop find_class(int index, unsigned int hash,
69 symbolHandle name, Handle loader);
70
71 klassOop find_shared_class(int index, unsigned int hash, symbolHandle name);
72
73 // Compiler support
74 klassOop try_get_next_class();
75
76 // GC support
77
78 void oops_do(OopClosure* f);
79 void always_strong_classes_do(OopClosure* blk);
80 void classes_do(void f(klassOop));
81 void classes_do(void f(klassOop, TRAPS), TRAPS);
82 void classes_do(void f(klassOop, oop));
83 void classes_do(void f(klassOop, oop, TRAPS), TRAPS);
84
85 void methods_do(void f(methodOop));
86
87
88 // Classes loaded by the bootstrap loader are always strongly reachable.
89 // If we're not doing class unloading, all classes are strongly reachable.
90 static bool is_strongly_reachable(oop class_loader, oop klass) {
91 assert (klass != NULL, "should have non-null klass");
92 return (class_loader == NULL || !ClassUnloading);
93 }
94
95 // Unload (that is, break root links to) all unmarked classes and
96 // loaders. Returns "true" iff something was unloaded.
97 bool do_unloading(BoolObjectClosure* is_alive);
98
99 // Protection domains
100 klassOop find(int index, unsigned int hash, symbolHandle name,
101 Handle loader, Handle protection_domain, TRAPS);
102 bool is_valid_protection_domain(int index, unsigned int hash,
103 symbolHandle name, Handle class_loader,
104 Handle protection_domain);
105 void add_protection_domain(int index, unsigned int hash,
106 instanceKlassHandle klass, Handle loader,
107 Handle protection_domain, TRAPS);
108
109 // Sharing support
110 void dump(SerializeOopClosure* soc);
111 void restore(SerializeOopClosure* soc);
112 void reorder_dictionary();
113
114
115 #ifndef PRODUCT
116 void print();
117 #endif
118 void verify();
119 };
120
121 // The following classes can be in dictionary.cpp, but we need these
122 // to be in header file so that SA's vmStructs can access.
123
124 class ProtectionDomainEntry :public CHeapObj {
125 friend class VMStructs;
126 public:
127 ProtectionDomainEntry* _next;
128 oop _protection_domain;
129
130 ProtectionDomainEntry(oop protection_domain, ProtectionDomainEntry* next) {
131 _protection_domain = protection_domain;
132 _next = next;
133 }
134
135 ProtectionDomainEntry* next() { return _next; }
136 oop protection_domain() { return _protection_domain; }
137 };
138
139 // An entry in the system dictionary, this describes a class as
140 // { klassOop, loader, protection_domain }.
141
142 class DictionaryEntry : public HashtableEntry {
143 friend class VMStructs;
144 private:
145 // Contains the set of approved protection domains that can access
146 // this system dictionary entry.
147 ProtectionDomainEntry* _pd_set;
148 oop _loader;
149
150
151 public:
152 // Tells whether a protection is in the approved set.
153 bool contains_protection_domain(oop protection_domain) const;
154 // Adds a protection domain to the approved set.
155 void add_protection_domain(oop protection_domain);
156
157 klassOop klass() const { return (klassOop)literal(); }
158 klassOop* klass_addr() { return (klassOop*)literal_addr(); }
159
160 DictionaryEntry* next() const {
161 return (DictionaryEntry*)HashtableEntry::next();
162 }
163
164 DictionaryEntry** next_addr() {
165 return (DictionaryEntry**)HashtableEntry::next_addr();
166 }
167
168 oop loader() const { return _loader; }
169 void set_loader(oop loader) { _loader = loader; }
170 oop* loader_addr() { return &_loader; }
171
172 ProtectionDomainEntry* pd_set() const { return _pd_set; }
173 void set_pd_set(ProtectionDomainEntry* pd_set) { _pd_set = pd_set; }
174
175 bool has_protection_domain() { return _pd_set != NULL; }
176
177 // Tells whether the initiating class' protection can access the this _klass
178 bool is_valid_protection_domain(Handle protection_domain) {
179 if (!ProtectionDomainVerification) return true;
180 if (!SystemDictionary::has_checkPackageAccess()) return true;
181
182 return protection_domain() == NULL
183 ? true
184 : contains_protection_domain(protection_domain());
185 }
186
187
188 void protection_domain_set_oops_do(OopClosure* f) {
189 for (ProtectionDomainEntry* current = _pd_set;
190 current != NULL;
191 current = current->_next) {
192 f->do_oop(&(current->_protection_domain));
193 }
194 }
195
196 void verify_protection_domain_set() {
197 for (ProtectionDomainEntry* current = _pd_set;
198 current != NULL;
199 current = current->_next) {
200 current->_protection_domain->verify();
201 }
202 }
203
204 bool equals(symbolOop class_name, oop class_loader) const {
205 klassOop klass = (klassOop)literal();
206 return (instanceKlass::cast(klass)->name() == class_name &&
207 _loader == class_loader);
208 }
209
210 void print() {
211 int count = 0;
212 for (ProtectionDomainEntry* current = _pd_set;
213 current != NULL;
214 current = current->_next) {
215 count++;
216 }
217 tty->print_cr("pd set = #%d", count);
218 }
219 };
220
221 // Entry in a SymbolPropertyTable, mapping a single symbolOop
222 // to a managed and an unmanaged pointer.
223 class SymbolPropertyEntry : public HashtableEntry {
224 friend class VMStructs;
225 private:
226 intptr_t _symbol_mode; // secondary key
227 oop _property_oop;
228 address _property_data;
229
230 public:
231 symbolOop symbol() const { return (symbolOop) literal(); }
232
233 intptr_t symbol_mode() const { return _symbol_mode; }
234 void set_symbol_mode(intptr_t m) { _symbol_mode = m; }
235
236 oop property_oop() const { return _property_oop; }
237 void set_property_oop(oop p) { _property_oop = p; }
238
239 address property_data() const { return _property_data; }
240 void set_property_data(address p) { _property_data = p; }
241
242 SymbolPropertyEntry* next() const {
243 return (SymbolPropertyEntry*)HashtableEntry::next();
244 }
245
246 SymbolPropertyEntry** next_addr() {
247 return (SymbolPropertyEntry**)HashtableEntry::next_addr();
248 }
249
250 oop* symbol_addr() { return literal_addr(); }
251 oop* property_oop_addr() { return &_property_oop; }
252
253 void print_on(outputStream* st) const {
254 symbol()->print_value_on(st);
255 st->print("/mode="INTX_FORMAT, symbol_mode());
256 st->print(" -> ");
257 bool printed = false;
258 if (property_oop() != NULL) {
259 property_oop()->print_value_on(st);
260 printed = true;
261 }
262 if (property_data() != NULL) {
263 if (printed) st->print(" and ");
264 st->print(INTPTR_FORMAT, property_data());
265 printed = true;
266 }
267 st->print_cr(printed ? "" : "(empty)");
268 }
269 };
270
271 // A system-internal mapping of symbols to pointers, both managed
272 // and unmanaged. Used to record the auto-generation of each method
273 // MethodHandle.invoke(S)T, for all signatures (S)T.
274 class SymbolPropertyTable : public Hashtable {
275 friend class VMStructs;
276 private:
277 SymbolPropertyEntry* bucket(int i) {
278 return (SymbolPropertyEntry*) Hashtable::bucket(i);
279 }
280
281 // The following method is not MT-safe and must be done under lock.
282 SymbolPropertyEntry** bucket_addr(int i) {
283 return (SymbolPropertyEntry**) Hashtable::bucket_addr(i);
284 }
285
286 void add_entry(int index, SymbolPropertyEntry* new_entry) {
287 ShouldNotReachHere();
288 }
289 void set_entry(int index, SymbolPropertyEntry* new_entry) {
290 ShouldNotReachHere();
291 }
292
293 SymbolPropertyEntry* new_entry(unsigned int hash, symbolOop symbol, intptr_t symbol_mode) {
294 SymbolPropertyEntry* entry = (SymbolPropertyEntry*) Hashtable::new_entry(hash, symbol);
295 entry->set_symbol_mode(symbol_mode);
296 entry->set_property_oop(NULL);
297 entry->set_property_data(NULL);
298 return entry;
299 }
300
301 public:
302 SymbolPropertyTable(int table_size);
303 SymbolPropertyTable(int table_size, HashtableBucket* t, int number_of_entries);
304
305 void free_entry(SymbolPropertyEntry* entry) {
306 Hashtable::free_entry(entry);
307 }
308
309 unsigned int compute_hash(symbolHandle sym, intptr_t symbol_mode) {
310 // Use the regular identity_hash.
311 return Hashtable::compute_hash(sym) ^ symbol_mode;
312 }
313
314 int index_for(symbolHandle name, intptr_t symbol_mode) {
315 return hash_to_index(compute_hash(name, symbol_mode));
316 }
317
318 // need not be locked; no state change
319 SymbolPropertyEntry* find_entry(int index, unsigned int hash, symbolHandle name, intptr_t name_mode);
320
321 // must be done under SystemDictionary_lock
322 SymbolPropertyEntry* add_entry(int index, unsigned int hash, symbolHandle name, intptr_t name_mode);
323
324 // GC support
325 void oops_do(OopClosure* f);
326 void methods_do(void f(methodOop));
327
328 // Sharing support
329 void dump(SerializeOopClosure* soc);
330 void restore(SerializeOopClosure* soc);
331 void reorder_dictionary();
332
333 #ifndef PRODUCT
334 void print();
335 #endif
336 void verify();
337 };
338