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. 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_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 35 class DictionaryEntry; 36 class BoolObjectClosure; 37 38 //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 39 // The data structure for the class loader data dictionaries. 40 41 class 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 loader_data() const50 ClassLoaderData* loader_data() const { return _loader_data; } 51 52 DictionaryEntry* get_entry(int index, unsigned int hash, Symbol* name); 53 54 public: 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 bucket(int i) const88 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. bucket_addr(int i)93 DictionaryEntry** bucket_addr(int i) { 94 return (DictionaryEntry**)Hashtable<InstanceKlass*, mtClass>::bucket_addr(i); 95 } 96 add_entry(int index,DictionaryEntry * new_entry)97 void add_entry(int index, DictionaryEntry* new_entry) { 98 Hashtable<InstanceKlass*, mtClass>::add_entry(index, (HashtableEntry<InstanceKlass*, mtClass>*)new_entry); 99 } 100 unlink_entry(DictionaryEntry * entry)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 }. 110 111 class 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 instance_klass() const142 InstanceKlass* instance_klass() const { return literal(); } klass_addr()143 InstanceKlass** klass_addr() { return (InstanceKlass**)literal_addr(); } 144 next() const145 DictionaryEntry* next() const { 146 return (DictionaryEntry*)HashtableEntry<InstanceKlass*, mtClass>::next(); 147 } 148 next_addr()149 DictionaryEntry** next_addr() { 150 return (DictionaryEntry**)HashtableEntry<InstanceKlass*, mtClass>::next_addr(); 151 } 152 pd_set() const153 ProtectionDomainEntry* pd_set() const { return _pd_set; } set_pd_set(ProtectionDomainEntry * new_head)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 is_valid_protection_domain(Handle protection_domain)157 bool is_valid_protection_domain(Handle protection_domain) { 158 if (!ProtectionDomainVerification) return true; 159 160 return protection_domain() == NULL 161 ? true 162 : contains_protection_domain(protection_domain()); 163 } 164 165 void verify_protection_domain_set(); 166 equals(const Symbol * class_name) const167 bool equals(const Symbol* class_name) const { 168 InstanceKlass* klass = (InstanceKlass*)literal(); 169 return (klass->name() == class_name); 170 } 171 172 void print_count(outputStream *st); 173 void verify(); 174 }; 175 176 // Entry in a SymbolPropertyTable, mapping a single Symbol* 177 // to a managed and an unmanaged pointer. 178 class SymbolPropertyEntry : public HashtableEntry<Symbol*, mtSymbol> { 179 friend class VMStructs; 180 private: 181 intptr_t _symbol_mode; // secondary key 182 Method* _method; 183 oop _method_type; 184 185 public: symbol() const186 Symbol* symbol() const { return literal(); } 187 symbol_mode() const188 intptr_t symbol_mode() const { return _symbol_mode; } set_symbol_mode(intptr_t m)189 void set_symbol_mode(intptr_t m) { _symbol_mode = m; } 190 method() const191 Method* method() const { return _method; } set_method(Method * p)192 void set_method(Method* p) { _method = p; } 193 method_type() const194 oop method_type() const { return _method_type; } method_type_addr()195 oop* method_type_addr() { return &_method_type; } set_method_type(oop p)196 void set_method_type(oop p) { _method_type = p; } 197 next() const198 SymbolPropertyEntry* next() const { 199 return (SymbolPropertyEntry*)HashtableEntry<Symbol*, mtSymbol>::next(); 200 } 201 next_addr()202 SymbolPropertyEntry** next_addr() { 203 return (SymbolPropertyEntry**)HashtableEntry<Symbol*, mtSymbol>::next_addr(); 204 } 205 print_entry(outputStream * st) const206 void print_entry(outputStream* st) const { 207 symbol()->print_value_on(st); 208 st->print("/mode=" INTX_FORMAT, symbol_mode()); 209 st->print(" -> "); 210 bool printed = false; 211 if (method() != NULL) { 212 method()->print_value_on(st); 213 printed = true; 214 } 215 if (method_type() != NULL) { 216 if (printed) st->print(" and "); 217 st->print(INTPTR_FORMAT, p2i((void *)method_type())); 218 printed = true; 219 } 220 st->print_cr(printed ? "" : "(empty)"); 221 } 222 }; 223 224 // A system-internal mapping of symbols to pointers, both managed 225 // and unmanaged. Used to record the auto-generation of each method 226 // MethodHandle.invoke(S)T, for all signatures (S)T. 227 class SymbolPropertyTable : public Hashtable<Symbol*, mtSymbol> { 228 friend class VMStructs; 229 private: 230 // The following method is not MT-safe and must be done under lock. bucket_addr(int i)231 SymbolPropertyEntry** bucket_addr(int i) { 232 return (SymbolPropertyEntry**) Hashtable<Symbol*, mtSymbol>::bucket_addr(i); 233 } 234 add_entry(int index,SymbolPropertyEntry * new_entry)235 void add_entry(int index, SymbolPropertyEntry* new_entry) { 236 ShouldNotReachHere(); 237 } set_entry(int index,SymbolPropertyEntry * new_entry)238 void set_entry(int index, SymbolPropertyEntry* new_entry) { 239 ShouldNotReachHere(); 240 } 241 new_entry(unsigned int hash,Symbol * symbol,intptr_t symbol_mode)242 SymbolPropertyEntry* new_entry(unsigned int hash, Symbol* symbol, intptr_t symbol_mode) { 243 SymbolPropertyEntry* entry = (SymbolPropertyEntry*) Hashtable<Symbol*, mtSymbol>::new_entry(hash, symbol); 244 // Hashtable with Symbol* literal must increment and decrement refcount. 245 symbol->increment_refcount(); 246 entry->set_symbol_mode(symbol_mode); 247 entry->set_method(NULL); 248 entry->set_method_type(NULL); 249 return entry; 250 } 251 252 public: 253 SymbolPropertyTable(int table_size); 254 SymbolPropertyTable(int table_size, HashtableBucket<mtSymbol>* t, int number_of_entries); 255 free_entry(SymbolPropertyEntry * entry)256 void free_entry(SymbolPropertyEntry* entry) { 257 // decrement Symbol refcount here because hashtable doesn't. 258 entry->literal()->decrement_refcount(); 259 Hashtable<Symbol*, mtSymbol>::free_entry(entry); 260 } 261 compute_hash(Symbol * sym,intptr_t symbol_mode)262 unsigned int compute_hash(Symbol* sym, intptr_t symbol_mode) { 263 // Use the regular identity_hash. 264 return Hashtable<Symbol*, mtSymbol>::compute_hash(sym) ^ symbol_mode; 265 } 266 index_for(Symbol * name,intptr_t symbol_mode)267 int index_for(Symbol* name, intptr_t symbol_mode) { 268 return hash_to_index(compute_hash(name, symbol_mode)); 269 } 270 271 // need not be locked; no state change 272 SymbolPropertyEntry* find_entry(int index, unsigned int hash, Symbol* name, intptr_t name_mode); 273 274 // must be done under SystemDictionary_lock 275 SymbolPropertyEntry* add_entry(int index, unsigned int hash, Symbol* name, intptr_t name_mode); 276 277 // GC support 278 void oops_do(OopClosure* f); 279 280 void methods_do(void f(Method*)); 281 282 void verify(); 283 bucket(int i)284 SymbolPropertyEntry* bucket(int i) { 285 return (SymbolPropertyEntry*) Hashtable<Symbol*, mtSymbol>::bucket(i); 286 } 287 }; 288 #endif // SHARE_CLASSFILE_DICTIONARY_HPP 289