1 /*
2 * Copyright (c) 2014, 2025, 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_CLASSFILE_SYSTEMDICTIONARYSHARED_HPP
26 #define SHARE_CLASSFILE_SYSTEMDICTIONARYSHARED_HPP
27
28 #include "cds/cds_globals.hpp"
29 #include "cds/filemap.hpp"
30 #include "cds/dumpTimeClassInfo.hpp"
31 #include "cds/lambdaProxyClassDictionary.hpp"
32 #include "cds/runTimeClassInfo.hpp"
33 #include "classfile/classLoaderData.hpp"
34 #include "classfile/packageEntry.hpp"
35 #include "classfile/systemDictionary.hpp"
36 #include "oops/klass.hpp"
37 #include "oops/oopHandle.hpp"
38
39
40 /*===============================================================================
41
42 Handling of the classes in the AppCDS archive
43
44 To ensure safety and to simplify the implementation, archived classes are
45 "segregated" into 2 types. The following rules describe how they
46 are stored and looked up.
47
48 [1] Category of archived classes
49
50 There are 2 disjoint groups of classes stored in the AppCDS archive:
51
52 BUILTIN: These classes may be defined ONLY by the BOOT/PLATFORM/APP
53 loaders.
54
55 UNREGISTERED: These classes may be defined ONLY by a ClassLoader
56 instance that's not listed above (using fingerprint matching)
57
58 [2] How classes from different categories are specified in the classlist:
59
60 Starting from JDK9, each class in the classlist may be specified with
61 these keywords: "id", "super", "interfaces", "loader" and "source".
62
63
64 BUILTIN Only the "id" keyword may be (optionally) specified. All other
65 keywords are forbidden.
66
67 The named class is looked up from the jimage and from
68 Xbootclasspath/a and CLASSPATH.
69
70 UNREGISTERED: The "id", "super", and "source" keywords must all be
71 specified.
72
73 The "interfaces" keyword must be specified if the class implements
74 one or more local interfaces. The "interfaces" keyword must not be
75 specified if the class does not implement local interfaces.
76
77 The named class is looked up from the location specified in the
78 "source" keyword.
79
80 Example classlist:
81
82 # BUILTIN
83 java/lang/Object id: 0
84 java/lang/Cloneable id: 1
85 java/lang/String
86
87 # UNREGISTERED
88 Bar id: 3 super: 0 interfaces: 1 source: /foo.jar
89
90
91 [3] Identifying the category of archived classes
92
93 BUILTIN: (C->shared_classpath_index() >= 0)
94 UNREGISTERED: (C->shared_classpath_index() == UNREGISTERED_INDEX (-9999))
95
96 [4] Lookup of archived classes at run time:
97
98 (a) BUILTIN loaders:
99
100 search _builtin_dictionary
101
102 (b) UNREGISTERED loaders:
103
104 search _unregistered_dictionary for an entry that matches the
105 (name, clsfile_len, clsfile_crc32).
106
107 ===============================================================================*/
108 #define UNREGISTERED_INDEX -9999
109
110 class BootstrapInfo;
111 class ClassFileStream;
112 class ConstantPoolCache;
113 class Dictionary;
114 class DumpTimeClassInfo;
115 class DumpTimeSharedClassTable;
116 class LambdaProxyClassDictionary;
117 class RunTimeClassInfo;
118 class RunTimeSharedDictionary;
119 class DumpTimeLambdaProxyClassDictionary;
120 class LambdaProxyClassKey;
121
122 class SharedClassLoadingMark {
123 private:
124 Thread* THREAD;
125 InstanceKlass* _klass;
126 public:
127 SharedClassLoadingMark(Thread* current, InstanceKlass* ik) : THREAD(current), _klass(ik) {}
128 ~SharedClassLoadingMark() {
129 assert(THREAD != nullptr, "Current thread is nullptr");
130 assert(_klass != nullptr, "InstanceKlass is nullptr");
131 if (HAS_PENDING_EXCEPTION) {
132 if (_klass->is_shared()) {
133 _klass->set_shared_loading_failed();
134 }
135 }
136 }
137 };
138
139 class SystemDictionaryShared: public SystemDictionary {
140 friend class CleanupDumpTimeLambdaProxyClassTable;
141
142 struct ArchiveInfo {
143 RunTimeSharedDictionary _builtin_dictionary;
144 RunTimeSharedDictionary _unregistered_dictionary;
145 LambdaProxyClassDictionary _lambda_proxy_class_dictionary;
146
147 const RunTimeLambdaProxyClassInfo* lookup_lambda_proxy_class(RunTimeLambdaProxyClassKey* key) {
148 return _lambda_proxy_class_dictionary.lookup(key, key->hash(), 0);
149 }
150
151 void print_on(const char* prefix, outputStream* st);
152 void print_table_statistics(const char* prefix, outputStream* st);
153 };
154
155 private:
156
157 static DumpTimeSharedClassTable* _dumptime_table;
158 static DumpTimeLambdaProxyClassDictionary* _dumptime_lambda_proxy_class_dictionary;
159
160 static ArchiveInfo _static_archive;
161 static ArchiveInfo _dynamic_archive;
162
163 static ArchiveInfo* get_archive(bool is_static_archive) {
164 return is_static_archive ? &_static_archive : &_dynamic_archive;
165 }
166
167 static InstanceKlass* load_shared_class_for_builtin_loader(
168 Symbol* class_name,
169 Handle class_loader,
170 TRAPS);
171 static InstanceKlass* acquire_class_for_current_thread(
172 InstanceKlass *ik,
173 Handle class_loader,
174 Handle protection_domain,
175 const ClassFileStream* cfs,
176 TRAPS);
177
178 // Guaranteed to return non-null value for non-shared classes.
179 // k must not be a shared class.
180 static DumpTimeClassInfo* get_info(InstanceKlass* k);
181 static DumpTimeClassInfo* get_info_locked(InstanceKlass* k);
182
183 static void write_dictionary(RunTimeSharedDictionary* dictionary,
184 bool is_builtin);
185 static void write_lambda_proxy_class_dictionary(LambdaProxyClassDictionary* dictionary);
186 static void cleanup_lambda_proxy_class_dictionary();
187 static void reset_registered_lambda_proxy_class(InstanceKlass* ik);
188 static bool is_jfr_event_class(InstanceKlass *k);
189 static bool check_for_exclusion_impl(InstanceKlass* k);
190 static void remove_dumptime_info(InstanceKlass* k) NOT_CDS_RETURN;
191 static bool has_been_redefined(InstanceKlass* k);
192 static InstanceKlass* retrieve_lambda_proxy_class(const RunTimeLambdaProxyClassInfo* info) NOT_CDS_RETURN_(nullptr);
193 DEBUG_ONLY(static bool _class_loading_may_happen;)
194
195 static void copy_verification_constraints_from_preimage(InstanceKlass* klass);
196 static void copy_linking_constraints_from_preimage(InstanceKlass* klass);
197
198 public:
199 static bool is_registered_lambda_proxy_class(InstanceKlass* ik);
200 static bool is_hidden_lambda_proxy(InstanceKlass* ik);
201 static bool is_early_klass(InstanceKlass* k); // Was k loaded while JvmtiExport::is_early_phase()==true
202 static bool has_archived_enum_objs(InstanceKlass* ik);
203 static void set_has_archived_enum_objs(InstanceKlass* ik);
204
205 static InstanceKlass* find_builtin_class(Symbol* class_name);
206
207 static const RunTimeClassInfo* find_record(RunTimeSharedDictionary* static_dict,
208 RunTimeSharedDictionary* dynamic_dict,
209 Symbol* name);
210
211 static bool has_platform_or_app_classes();
212
213 // Called by PLATFORM/APP loader only
214 static InstanceKlass* find_or_load_shared_class(Symbol* class_name,
215 Handle class_loader,
216 TRAPS);
217
218
219 static void allocate_shared_data_arrays(int size, TRAPS);
220
221 static bool is_builtin_loader(ClassLoaderData* loader_data);
222
223 static InstanceKlass* lookup_super_for_unregistered_class(Symbol* class_name,
224 Symbol* super_name, bool is_superclass);
225
226 static void initialize() NOT_CDS_RETURN;
227 static void init_dumptime_info(InstanceKlass* k) NOT_CDS_RETURN;
228 static void init_dumptime_info_from_preimage(InstanceKlass* k) NOT_CDS_RETURN;
229 static void handle_class_unloading(InstanceKlass* k) NOT_CDS_RETURN;
230
231 static Dictionary* boot_loader_dictionary() {
232 return ClassLoaderData::the_null_class_loader_data()->dictionary();
233 }
234
235 static void update_shared_entry(InstanceKlass* klass, int id);
236 static void set_shared_class_misc_info(InstanceKlass* k, ClassFileStream* cfs);
237
238 static InstanceKlass* lookup_from_stream(Symbol* class_name,
239 Handle class_loader,
240 Handle protection_domain,
241 const ClassFileStream* st,
242 TRAPS);
243 // "verification_constraints" are a set of checks performed by
244 // VerificationType::is_reference_assignable_from when verifying a shared class during
245 // dump time.
246 //
247 // With AppCDS, it is possible to override archived classes by calling
248 // ClassLoader.defineClass() directly. SystemDictionary::load_shared_class() already
249 // ensures that you cannot load a shared class if its super type(s) are changed. However,
250 // we need an additional check to ensure that the verification_constraints did not change
251 // between dump time and runtime.
252 static bool add_verification_constraint(InstanceKlass* k, Symbol* name,
253 Symbol* from_name, bool from_field_is_protected,
254 bool from_is_array, bool from_is_object) NOT_CDS_RETURN_(false);
255 static void check_verification_constraints(InstanceKlass* klass,
256 TRAPS) NOT_CDS_RETURN;
257 static void add_enum_klass_static_field(InstanceKlass* ik, int root_index);
258 static void set_class_has_failed_verification(InstanceKlass* ik) NOT_CDS_RETURN;
259 static bool has_class_failed_verification(InstanceKlass* ik) NOT_CDS_RETURN_(false);
260 static void add_lambda_proxy_class(InstanceKlass* caller_ik,
261 InstanceKlass* lambda_ik,
262 Symbol* invoked_name,
263 Symbol* invoked_type,
264 Symbol* method_type,
265 Method* member_method,
266 Symbol* instantiated_method_type, TRAPS) NOT_CDS_RETURN;
267 static void add_to_dump_time_lambda_proxy_class_dictionary(LambdaProxyClassKey& key,
268 InstanceKlass* proxy_klass) NOT_CDS_RETURN;
269 static InstanceKlass* get_shared_lambda_proxy_class(InstanceKlass* caller_ik,
270 Symbol* invoked_name,
271 Symbol* invoked_type,
272 Symbol* method_type,
273 Method* member_method,
274 Symbol* instantiated_method_type) NOT_CDS_RETURN_(nullptr);
275 static InstanceKlass* get_shared_nest_host(InstanceKlass* lambda_ik) NOT_CDS_RETURN_(nullptr);
276 static InstanceKlass* prepare_shared_lambda_proxy_class(InstanceKlass* lambda_ik,
277 InstanceKlass* caller_ik, TRAPS) NOT_CDS_RETURN_(nullptr);
278 static bool check_linking_constraints(Thread* current, InstanceKlass* klass) NOT_CDS_RETURN_(false);
279 static void record_linking_constraint(Symbol* name, InstanceKlass* klass,
280 Handle loader1, Handle loader2) NOT_CDS_RETURN;
281 static bool is_builtin(InstanceKlass* k) {
282 return (k->shared_classpath_index() != UNREGISTERED_INDEX);
283 }
284 static bool add_unregistered_class(Thread* current, InstanceKlass* k);
285
286 static void finish_exclusion_checks();
287 static DumpTimeSharedClassTable* dumptime_table() { return _dumptime_table; }
288
289 static bool should_be_excluded(Klass* k);
290 static bool check_for_exclusion(InstanceKlass* k, DumpTimeClassInfo* info);
291 static void validate_before_archiving(InstanceKlass* k);
292 static bool is_excluded_class(InstanceKlass* k);
293 static void set_excluded(InstanceKlass* k);
294 static void set_excluded_locked(InstanceKlass* k);
295 static bool warn_excluded(InstanceKlass* k, const char* reason);
296 static void dumptime_classes_do(class MetaspaceClosure* it);
297 static size_t estimate_size_for_archive();
298 static void write_to_archive(bool is_static_archive = true);
299 static void adjust_lambda_proxy_class_dictionary();
300 static void serialize_dictionary_headers(class SerializeClosure* soc,
301 bool is_static_archive = true);
302 static void serialize_vm_classes(class SerializeClosure* soc);
303 static void print() { return print_on(tty); }
304 static void print_on(outputStream* st) NOT_CDS_RETURN;
305 static void print_shared_archive(outputStream* st, bool is_static = true) NOT_CDS_RETURN;
306 static void print_table_statistics(outputStream* st) NOT_CDS_RETURN;
307 static bool is_dumptime_table_empty() NOT_CDS_RETURN_(true);
308 static bool is_supported_invokedynamic(BootstrapInfo* bsi) NOT_CDS_RETURN_(false);
309 DEBUG_ONLY(static bool class_loading_may_happen() {return _class_loading_may_happen;})
310
311 #ifdef ASSERT
312 // This object marks a critical period when writing the CDS archive. During this
313 // period, the JVM must not load any new classes, so as to avoid adding new
314 // items in the SystemDictionaryShared::_dumptime_table.
315 class NoClassLoadingMark: public StackObj {
316 public:
317 NoClassLoadingMark() {
318 assert(_class_loading_may_happen, "must not be nested");
319 _class_loading_may_happen = false;
320 }
321 ~NoClassLoadingMark() {
322 _class_loading_may_happen = true;
323 }
324 };
325 #endif
326
327 template <typename T>
328 static unsigned int hash_for_shared_dictionary_quick(T* ptr) {
329 assert(MetaspaceObj::is_shared((const MetaspaceObj*)ptr), "must be");
330 assert(ptr > (T*)SharedBaseAddress, "must be");
331 uintx offset = uintx(ptr) - uintx(SharedBaseAddress);
332 return primitive_hash<uintx>(offset);
333 }
334
335 static unsigned int hash_for_shared_dictionary(address ptr);
336 };
337
338 #endif // SHARE_CLASSFILE_SYSTEMDICTIONARYSHARED_HPP