1 /*
   2 * Copyright (c) 2016, 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 #include "cds/aotLogging.hpp"
  26 #include "cds/aotMetaspace.hpp"
  27 #include "cds/archiveBuilder.hpp"
  28 #include "cds/cdsConfig.hpp"
  29 #include "classfile/classFileParser.hpp"
  30 #include "classfile/classLoader.hpp"
  31 #include "classfile/classLoaderData.inline.hpp"
  32 #include "classfile/classLoaderDataShared.hpp"
  33 #include "classfile/javaAssertions.hpp"
  34 #include "classfile/javaClasses.inline.hpp"
  35 #include "classfile/moduleEntry.hpp"
  36 #include "classfile/modules.hpp"
  37 #include "classfile/packageEntry.hpp"
  38 #include "classfile/stringTable.hpp"
  39 #include "classfile/symbolTable.hpp"
  40 #include "classfile/systemDictionary.hpp"
  41 #include "classfile/vmClasses.hpp"
  42 #include "classfile/vmSymbols.hpp"
  43 #include "jvm.h"
  44 #include "logging/log.hpp"
  45 #include "logging/logStream.hpp"
  46 #include "memory/resourceArea.hpp"
  47 #include "prims/jvmtiExport.hpp"
  48 #include "runtime/arguments.hpp"
  49 #include "runtime/globals_extension.hpp"
  50 #include "runtime/handles.inline.hpp"
  51 #include "runtime/javaCalls.hpp"
  52 #include "runtime/jniHandles.inline.hpp"
  53 #include "utilities/formatBuffer.hpp"
  54 #include "utilities/stringUtils.hpp"
  55 #include "utilities/utf8.hpp"
  56 
  57 static bool verify_module_name(const char *module_name, int len) {
  58   assert(module_name != nullptr, "invariant");
  59   return (len > 0 && len <= Symbol::max_length());
  60 }
  61 
  62 static bool verify_package_name(const char* package_name, int len) {
  63   assert(package_name != nullptr, "Package name derived from non-null jstring can't be null");
  64   return (len > 0 && len <= Symbol::max_length() &&
  65     ClassFileParser::verify_unqualified_name(package_name, len,
  66     ClassFileParser::LegalClass));
  67 }
  68 
  69 static char* get_module_name(oop module, int& len, TRAPS) {
  70   oop name_oop = java_lang_Module::name(module);
  71   if (name_oop == nullptr) {
  72     THROW_MSG_NULL(vmSymbols::java_lang_NullPointerException(), "Null module name");
  73   }
  74   size_t utf8_len;
  75   char* module_name = java_lang_String::as_utf8_string(name_oop, utf8_len);
  76   len = checked_cast<int>(utf8_len); // module names are < 64K
  77   if (!verify_module_name(module_name, len)) {
  78     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(),
  79                    err_msg("Invalid module name: %s", module_name));
  80   }
  81   return module_name;
  82 }
  83 
  84 static Symbol* as_symbol(jstring str_object) {
  85   if (str_object == nullptr) {
  86     return nullptr;
  87   }
  88   size_t len;
  89   char* str = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(str_object), len);
  90   return SymbolTable::new_symbol(str, checked_cast<int>(len));
  91 }
  92 
  93 ModuleEntryTable* Modules::get_module_entry_table(Handle h_loader) {
  94   // This code can be called during start-up, before the classLoader's classLoader data got
  95   // created.  So, call register_loader() to make sure the classLoader data gets created.
  96   ClassLoaderData *loader_cld = SystemDictionary::register_loader(h_loader);
  97   return loader_cld->modules();
  98 }
  99 
 100 static PackageEntryTable* get_package_entry_table(Handle h_loader) {
 101   // This code can be called during start-up, before the classLoader's classLoader data got
 102   // created.  So, call register_loader() to make sure the classLoader data gets created.
 103   ClassLoaderData *loader_cld = SystemDictionary::register_loader(h_loader);
 104   return loader_cld->packages();
 105 }
 106 
 107 static ModuleEntry* get_module_entry(Handle module, TRAPS) {
 108   if (!java_lang_Module::is_instance(module())) {
 109     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(),
 110                    "module is not an instance of type java.lang.Module");
 111   }
 112   return java_lang_Module::module_entry(module());
 113 }
 114 
 115 
 116 static PackageEntry* get_locked_package_entry(ModuleEntry* module_entry, const char* package_name, int len) {
 117   assert(Module_lock->owned_by_self(), "should have the Module_lock");
 118   assert(package_name != nullptr, "Precondition");
 119   TempNewSymbol pkg_symbol = SymbolTable::new_symbol(package_name, len);
 120   PackageEntryTable* package_entry_table = module_entry->loader_data()->packages();
 121   assert(package_entry_table != nullptr, "Unexpected null package entry table");
 122   PackageEntry* package_entry = package_entry_table->locked_lookup_only(pkg_symbol);
 123   assert(package_entry == nullptr || package_entry->module() == module_entry, "Unexpectedly found a package linked to another module");
 124   return package_entry;
 125 }
 126 
 127 static PackageEntry* get_package_entry_by_name(Symbol* package, Handle h_loader) {
 128   if (package != nullptr) {
 129     PackageEntryTable* const package_entry_table =
 130       get_package_entry_table(h_loader);
 131     assert(package_entry_table != nullptr, "Unexpected null package entry table");
 132     return package_entry_table->lookup_only(package);
 133   }
 134   return nullptr;
 135 }
 136 
 137 bool Modules::is_package_defined(Symbol* package, Handle h_loader) {
 138   PackageEntry* res = get_package_entry_by_name(package, h_loader);
 139   return res != nullptr;
 140 }
 141 
 142 // Converts the String oop to an internal package
 143 // Will use the provided buffer if it's sufficiently large, otherwise allocates
 144 // a resource array
 145 // The length of the resulting string will be assigned to utf8_len
 146 static const char* as_internal_package(oop package_string, char* buf, size_t buflen, int& utf8_len) {
 147   size_t full_utf8_len;
 148   char* package_name = java_lang_String::as_utf8_string_full(package_string, buf, buflen, full_utf8_len);
 149   utf8_len = checked_cast<int>(full_utf8_len); // package names are < 64K
 150 
 151   // Turn all '/'s into '.'s
 152   for (int index = 0; index < utf8_len; index++) {
 153     if (package_name[index] == JVM_SIGNATURE_DOT) {
 154       package_name[index] = JVM_SIGNATURE_SLASH;
 155     }
 156   }
 157   return package_name;
 158 }
 159 
 160 static void define_javabase_module(Handle module_handle, jstring version, jstring location,
 161                                    objArrayHandle pkgs, int num_packages, TRAPS) {
 162   ResourceMark rm(THREAD);
 163 
 164   // Obtain java.base's module version
 165   TempNewSymbol version_symbol = as_symbol(version);
 166 
 167   // Obtain java.base's location
 168   TempNewSymbol location_symbol = as_symbol(location);
 169 
 170   // Check that the packages are syntactically ok.
 171   char buf[128];
 172   GrowableArray<Symbol*>* pkg_list = new GrowableArray<Symbol*>(num_packages);
 173   for (int x = 0; x < num_packages; x++) {
 174     oop pkg_str = pkgs->obj_at(x);
 175 
 176     if (pkg_str == nullptr || pkg_str->klass() != vmClasses::String_klass()) {
 177       THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
 178                 err_msg("Bad package name"));
 179     }
 180 
 181     int package_len;
 182     const char* package_name = as_internal_package(pkg_str, buf, sizeof(buf), package_len);
 183     if (!verify_package_name(package_name, package_len)) {
 184       THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
 185                 err_msg("Invalid package name: %s for module: " JAVA_BASE_NAME, package_name));
 186     }
 187     Symbol* pkg_symbol = SymbolTable::new_symbol(package_name, package_len);
 188     pkg_list->append(pkg_symbol);
 189   }
 190 
 191   // Validate java_base's loader is the boot loader.
 192   oop loader = java_lang_Module::loader(module_handle());
 193   if (loader != nullptr) {
 194     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
 195               "Class loader must be the boot class loader");
 196   }
 197   Handle h_loader(THREAD, loader);
 198 
 199   // Ensure the boot loader's PackageEntryTable has been created
 200   PackageEntryTable* package_table = get_package_entry_table(h_loader);
 201   assert(pkg_list->length() == 0 || package_table != nullptr, "Bad package_table");
 202 
 203   // Ensure java.base's ModuleEntry has been created
 204   assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, "No ModuleEntry for " JAVA_BASE_NAME);
 205 
 206   bool duplicate_javabase = false;
 207   {
 208     MutexLocker m1(THREAD, Module_lock);
 209 
 210     if (ModuleEntryTable::javabase_defined()) {
 211       duplicate_javabase = true;
 212     } else {
 213 
 214       // Verify that all java.base packages created during bootstrapping are in
 215       // pkg_list.  If any are not in pkg_list, than a non-java.base class was
 216       // loaded erroneously pre java.base module definition.
 217       package_table->verify_javabase_packages(pkg_list);
 218 
 219       // loop through and add any new packages for java.base
 220       for (int x = 0; x < pkg_list->length(); x++) {
 221         // Some of java.base's packages were added early in bootstrapping, ignore duplicates.
 222         package_table->locked_create_entry_if_absent(pkg_list->at(x),
 223                                                      ModuleEntryTable::javabase_moduleEntry());
 224         assert(package_table->locked_lookup_only(pkg_list->at(x)) != nullptr,
 225                "Unable to create a " JAVA_BASE_NAME " package entry");
 226         // Unable to have a GrowableArray of TempNewSymbol.  Must decrement the refcount of
 227         // the Symbol* that was created above for each package. The refcount was incremented
 228         // by SymbolTable::new_symbol and as well by the PackageEntry creation.
 229         pkg_list->at(x)->decrement_refcount();
 230       }
 231 
 232       // Finish defining java.base's ModuleEntry
 233       ModuleEntryTable::finalize_javabase(module_handle, version_symbol, location_symbol);
 234     }
 235   }
 236   if (duplicate_javabase) {
 237     THROW_MSG(vmSymbols::java_lang_InternalError(),
 238               "Module " JAVA_BASE_NAME " is already defined");
 239   }
 240 
 241   // Only the thread that actually defined the base module will get here,
 242   // so no locking is needed.
 243 
 244   // Patch any previously loaded class's module field with java.base's java.lang.Module.
 245   ModuleEntryTable::patch_javabase_entries(THREAD, module_handle);
 246 
 247   log_info(module, load)(JAVA_BASE_NAME " location: %s",
 248                          location_symbol != nullptr ? location_symbol->as_C_string() : "nullptr");
 249   log_debug(module)("define_javabase_module(): Definition of module: "
 250                     JAVA_BASE_NAME ", version: %s, location: %s, package #: %d",
 251                     version_symbol != nullptr ? version_symbol->as_C_string() : "nullptr",
 252                     location_symbol != nullptr ? location_symbol->as_C_string() : "nullptr",
 253                     pkg_list->length());
 254 
 255   // packages defined to java.base
 256   if (log_is_enabled(Trace, module)) {
 257     for (int x = 0; x < pkg_list->length(); x++) {
 258       log_trace(module)("define_javabase_module(): creation of package %s for module " JAVA_BASE_NAME,
 259                         (pkg_list->at(x))->as_C_string());
 260     }
 261   }
 262 }
 263 
 264 // Caller needs ResourceMark.
 265 static void throw_dup_pkg_exception(const char* module_name, PackageEntry* package, TRAPS) {
 266   const char* package_name = package->name()->as_C_string();
 267   if (package->module()->is_named()) {
 268     THROW_MSG(vmSymbols::java_lang_IllegalStateException(),
 269       err_msg("Package %s for module %s is already in another module, %s, defined to the class loader",
 270               package_name, module_name, package->module()->name()->as_C_string()));
 271   } else {
 272     THROW_MSG(vmSymbols::java_lang_IllegalStateException(),
 273       err_msg("Package %s for module %s is already in the unnamed module defined to the class loader",
 274               package_name, module_name));
 275   }
 276 }
 277 
 278 void Modules::define_module(Handle module, jboolean is_open, jstring version,
 279                             jstring location, jobjectArray packages, TRAPS) {
 280   ResourceMark rm(THREAD);
 281 
 282   if (module.is_null()) {
 283     THROW_MSG(vmSymbols::java_lang_NullPointerException(), "Null module object");
 284   }
 285 
 286   if (!java_lang_Module::is_instance(module())) {
 287     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
 288               "module is not an instance of type java.lang.Module");
 289   }
 290 
 291   int module_name_len;
 292   char* module_name = get_module_name(module(), module_name_len, CHECK);
 293   if (module_name == nullptr) {
 294     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
 295               "Module name cannot be null");
 296   }
 297 
 298   // Resolve packages
 299   objArrayHandle packages_h(THREAD, objArrayOop(JNIHandles::resolve(packages)));
 300   int num_packages = (packages_h.is_null() ? 0 : packages_h->length());
 301   if (strncmp(module_name, "jdk.proxy", 9) != 0) {
 302     check_cds_restrictions(Handle(), Handle(), CHECK);
 303   }
 304 
 305   // Special handling of java.base definition
 306   if (strcmp(module_name, JAVA_BASE_NAME) == 0) {
 307     assert(is_open == JNI_FALSE, "java.base module cannot be open");
 308     define_javabase_module(module, version, location, packages_h, num_packages, CHECK);
 309     return;
 310   }
 311 
 312   oop loader = java_lang_Module::loader(module());
 313   Handle h_loader = Handle(THREAD, loader);
 314   // define_module can be called during start-up, before the class loader's ClassLoaderData
 315   // has been created.  SystemDictionary::register_loader ensures creation, if needed.
 316   ClassLoaderData* loader_data = SystemDictionary::register_loader(h_loader);
 317   assert(loader_data != nullptr, "class loader data shouldn't be null");
 318 
 319   // Only modules defined to either the boot or platform class loader, can define a "java/" package.
 320   bool java_pkg_disallowed = !h_loader.is_null() &&
 321         !SystemDictionary::is_platform_class_loader(h_loader());
 322 
 323   // Check that the list of packages has no duplicates and that the
 324   // packages are syntactically ok.
 325   char buf[128];
 326   GrowableArray<Symbol*>* pkg_list = new GrowableArray<Symbol*>(num_packages);
 327   for (int x = 0; x < num_packages; x++) {
 328     oop pkg_str = packages_h->obj_at(x);
 329     if (pkg_str == nullptr || pkg_str->klass() != vmClasses::String_klass()) {
 330       THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
 331                 err_msg("Bad package name"));
 332     }
 333 
 334     int package_len;
 335     const char* package_name = as_internal_package(pkg_str, buf, sizeof(buf), package_len);
 336     if (!verify_package_name(package_name, package_len)) {
 337       THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
 338                 err_msg("Invalid package name: %s for module: %s",
 339                         package_name, module_name));
 340     }
 341 
 342     // Only modules defined to either the boot or platform class loader, can define a "java/" package.
 343     if (java_pkg_disallowed &&
 344         (strncmp(package_name, JAVAPKG, JAVAPKG_LEN) == 0 &&
 345           (package_name[JAVAPKG_LEN] == JVM_SIGNATURE_SLASH || package_name[JAVAPKG_LEN] == '\0'))) {
 346       const char* class_loader_name = loader_data->loader_name_and_id();
 347       size_t pkg_len = strlen(package_name);
 348       char* pkg_name = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, pkg_len + 1);
 349       strncpy(pkg_name, package_name, pkg_len + 1);
 350       StringUtils::replace_no_expand(pkg_name, "/", ".");
 351       const char* msg_text1 = "Class loader (instance of): ";
 352       const char* msg_text2 = " tried to define prohibited package name: ";
 353       size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + pkg_len + 1;
 354       char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
 355       jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, pkg_name);
 356       THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), message);
 357     }
 358 
 359     Symbol* pkg_symbol = SymbolTable::new_symbol(package_name, package_len);
 360     pkg_list->append(pkg_symbol);
 361   }
 362 
 363   ModuleEntryTable* module_table = get_module_entry_table(h_loader);
 364   assert(module_table != nullptr, "module entry table shouldn't be null");
 365 
 366   // Create symbol* entry for module name.
 367   TempNewSymbol module_symbol = SymbolTable::new_symbol(module_name, module_name_len);
 368 
 369   bool dupl_modules = false;
 370 
 371   // Create symbol for module version.
 372   TempNewSymbol version_symbol = as_symbol(version);
 373 
 374   // Create symbol* entry for module location.
 375   TempNewSymbol location_symbol = as_symbol(location);
 376 
 377   PackageEntryTable* package_table = nullptr;
 378   PackageEntry* existing_pkg = nullptr;
 379   {
 380     MutexLocker ml(THREAD, Module_lock);
 381 
 382     if (num_packages > 0) {
 383       package_table = get_package_entry_table(h_loader);
 384       assert(package_table != nullptr, "Missing package_table");
 385 
 386       // Check that none of the packages exist in the class loader's package table.
 387       for (int x = 0; x < pkg_list->length(); x++) {
 388         existing_pkg = package_table->locked_lookup_only(pkg_list->at(x));
 389         if (existing_pkg != nullptr) {
 390           // This could be because the module was already defined.  If so,
 391           // report that error instead of the package error.
 392           if (module_table->lookup_only(module_symbol) != nullptr) {
 393             dupl_modules = true;
 394           }
 395           break;
 396         }
 397       }
 398     }  // if (num_packages > 0)...
 399 
 400     // Add the module and its packages.
 401     if (!dupl_modules && existing_pkg == nullptr) {
 402       if (module_table->lookup_only(module_symbol) == nullptr) {
 403         // Create the entry for this module in the class loader's module entry table.
 404         ModuleEntry* module_entry = module_table->locked_create_entry(module,
 405                                     (is_open == JNI_TRUE), module_symbol,
 406                                     version_symbol, location_symbol, loader_data);
 407         assert(module_entry != nullptr, "module_entry creation failed");
 408 
 409         // Add the packages.
 410         assert(pkg_list->length() == 0 || package_table != nullptr, "Bad package table");
 411         for (int y = 0; y < pkg_list->length(); y++) {
 412           package_table->locked_create_entry(pkg_list->at(y), module_entry);
 413 
 414           // Unable to have a GrowableArray of TempNewSymbol.  Must decrement the refcount of
 415           // the Symbol* that was created above for each package. The refcount was incremented
 416           // by SymbolTable::new_symbol and as well by the PackageEntry creation.
 417           pkg_list->at(y)->decrement_refcount();
 418         }
 419 
 420         // Store pointer to ModuleEntry record in java.lang.Module object.
 421         java_lang_Module::set_module_entry(module(), module_entry);
 422       } else {
 423          dupl_modules = true;
 424       }
 425     }
 426   }  // Release the lock
 427 
 428   // any errors ?
 429   if (dupl_modules) {
 430      THROW_MSG(vmSymbols::java_lang_IllegalStateException(),
 431                err_msg("Module %s is already defined", module_name));
 432   } else if (existing_pkg != nullptr) {
 433       throw_dup_pkg_exception(module_name, existing_pkg, CHECK);
 434   }
 435 
 436   log_info(module, load)("%s location: %s", module_name,
 437                          location_symbol != nullptr ? location_symbol->as_C_string() : "null");
 438   LogTarget(Debug, module) lt;
 439   if (lt.is_enabled()) {
 440     LogStream ls(lt);
 441     ls.print("define_module(): creation of module: %s, version: %s, location: %s, ",
 442                  module_name, version_symbol != nullptr ? version_symbol->as_C_string() : "null",
 443                  location_symbol != nullptr ? location_symbol->as_C_string() : "null");
 444     loader_data->print_value_on(&ls);
 445     ls.print_cr(", package #: %d", pkg_list->length());
 446     for (int y = 0; y < pkg_list->length(); y++) {
 447       log_trace(module)("define_module(): creation of package %s for module %s",
 448                         (pkg_list->at(y))->as_C_string(), module_name);
 449     }
 450   }
 451 
 452   // If the module is defined to the boot loader and an exploded build is being
 453   // used, prepend <java.home>/modules/modules_name to the boot class path.
 454   if (h_loader.is_null() && !ClassLoader::has_jrt_entry()) {
 455     ClassLoader::add_to_exploded_build_list(THREAD, module_symbol);
 456   }
 457 
 458 #if COMPILER2_OR_JVMCI
 459   // Special handling of jdk.incubator.vector
 460   if (strcmp(module_name, "jdk.incubator.vector") == 0) {
 461     if (FLAG_IS_DEFAULT(EnableVectorSupport)) {
 462       FLAG_SET_DEFAULT(EnableVectorSupport, true);
 463     }
 464     if (EnableVectorSupport && FLAG_IS_DEFAULT(EnableVectorReboxing)) {
 465       FLAG_SET_DEFAULT(EnableVectorReboxing, true);
 466     }
 467     if (EnableVectorSupport && EnableVectorReboxing && FLAG_IS_DEFAULT(EnableVectorAggressiveReboxing)) {
 468       FLAG_SET_DEFAULT(EnableVectorAggressiveReboxing, true);
 469     }
 470     log_info(compilation)("EnableVectorSupport=%s",            (EnableVectorSupport            ? "true" : "false"));
 471     log_info(compilation)("EnableVectorReboxing=%s",           (EnableVectorReboxing           ? "true" : "false"));
 472     log_info(compilation)("EnableVectorAggressiveReboxing=%s", (EnableVectorAggressiveReboxing ? "true" : "false"));
 473   }
 474 #endif // COMPILER2_OR_JVMCI
 475 }
 476 
 477 #if INCLUDE_CDS_JAVA_HEAP
 478 static bool _seen_boot_unnamed_module = false;
 479 static bool _seen_platform_unnamed_module = false;
 480 static bool _seen_system_unnamed_module = false;
 481 
 482 // Validate the states of an java.lang.Module oop to be archived.
 483 void Modules::check_archived_module_oop(oop orig_module_obj) {
 484   assert(CDSConfig::is_dumping_full_module_graph(), "must be");
 485   assert(java_lang_Module::is_instance(orig_module_obj), "must be");
 486 
 487   ModuleEntry* orig_module_ent = java_lang_Module::module_entry_raw(orig_module_obj);
 488   if (orig_module_ent == nullptr) {
 489     // These special java.lang.Module oops are created in Java code. They are not
 490     // defined via Modules::define_module(), so they don't have a ModuleEntry:
 491     //     java.lang.Module::ALL_UNNAMED_MODULE
 492     //     java.lang.Module::EVERYONE_MODULE
 493     //     jdk.internal.loader.ClassLoaders$BootClassLoader::unnamedModule
 494     log_info(aot, module)("Archived java.lang.Module oop " PTR_FORMAT " with no ModuleEntry*", p2i(orig_module_obj));
 495     assert(java_lang_Module::name(orig_module_obj) == nullptr, "must be unnamed");
 496   } else {
 497     // This java.lang.Module oop has an ModuleEntry*. Check if the latter is archived.
 498     if (log_is_enabled(Info, aot, module)) {
 499       ResourceMark rm;
 500       LogStream ls(Log(aot, module)::info());
 501       ls.print("Archived java.lang.Module oop " PTR_FORMAT " for ", p2i(orig_module_obj));
 502       orig_module_ent->print(&ls);
 503     }
 504 
 505     // We only archive the default module graph, which should contain only java.lang.Module oops
 506     // for the 3 built-in loaders (boot/platform/system)
 507     ClassLoaderData* loader_data = orig_module_ent->loader_data();
 508     assert(loader_data->is_builtin_class_loader_data(), "must be");
 509 
 510     if (orig_module_ent->name() != nullptr) {
 511       // For each named module, we archive both the java.lang.Module oop and the ModuleEntry.
 512       assert(orig_module_ent->has_been_archived(), "sanity");
 513     } else {
 514       // We always archive unnamed module oop for boot, platform, and system loaders.
 515       precond(orig_module_ent->should_be_archived());
 516       precond(orig_module_ent->has_been_archived());
 517 
 518       if (loader_data->is_boot_class_loader_data()) {
 519         assert(!_seen_boot_unnamed_module, "only once");
 520         _seen_boot_unnamed_module = true;
 521       } else if (SystemDictionary::is_platform_class_loader(loader_data->class_loader())) {
 522         assert(!_seen_platform_unnamed_module, "only once");
 523         _seen_platform_unnamed_module = true;
 524       } else if (SystemDictionary::is_system_class_loader(loader_data->class_loader())) {
 525         assert(!_seen_system_unnamed_module, "only once");
 526         _seen_system_unnamed_module = true;
 527       } else {
 528         ShouldNotReachHere();
 529       }
 530     }
 531   }
 532 }
 533 
 534 void Modules::verify_archived_modules() {
 535   ModuleEntry::verify_archived_module_entries();
 536 }
 537 
 538 class Modules::ArchivedProperty {
 539   const char* _prop;
 540   const bool _numbered;
 541   const char* _archived_value;
 542 
 543   const char* get_flattened_value() const {
 544     if (_numbered) {
 545       return get_numbered_property_as_sorted_string();
 546     } else {
 547       return Arguments::get_property(_prop);
 548     }
 549   }
 550 
 551   void runtime_check() const;
 552   const char* get_numbered_property_as_sorted_string() const;
 553 
 554 public:
 555   ArchivedProperty(const char* prop, bool numbered)
 556     : _prop(prop), _numbered(numbered), _archived_value(nullptr) {}
 557 
 558   void dump() {
 559     ResourceMark rm;
 560     const char* str = get_flattened_value();
 561     if (str != nullptr) {
 562       _archived_value = ArchiveBuilder::current()->ro_strdup(str);
 563     }
 564   }
 565 
 566   void serialize(SerializeClosure* soc) {
 567     soc->do_ptr(&_archived_value);
 568     if (soc->reading()) {
 569       runtime_check();
 570       // Don't hold onto the pointer, in case we might decide to unmap the archive.
 571       _archived_value = nullptr;
 572     }
 573   }
 574 };
 575 
 576 Modules::ArchivedProperty Modules::_archived_props[] = {
 577   // non-numbered
 578   {"jdk.module.main", false},
 579 
 580   // numbered
 581   {"jdk.module.addexports", true},             // --add-exports
 582   {"jdk.module.addmods", true},                // --add-modules
 583   {"jdk.module.enable.native.access", true},   // --enable-native-access
 584   {"jdk.module.addopens", true},               // --add-opens
 585   {"jdk.module.addreads", true},               // --add-reads
 586 };
 587 
 588 constexpr size_t Modules::num_archived_props() {
 589   return sizeof(_archived_props) / sizeof(_archived_props[0]);
 590 }
 591 
 592 Modules::ArchivedProperty& Modules::archived_prop(size_t i) {
 593   assert(i < num_archived_props(), "oob");
 594   return _archived_props[i];
 595 }
 596 
 597 void Modules::ArchivedProperty::runtime_check() const {
 598   ResourceMark rm;
 599   const char* runtime_value = get_flattened_value();
 600   aot_log_info(aot)("archived module property %s: %s", _prop,
 601                 _archived_value != nullptr ? _archived_value : "(null)");
 602 
 603   bool disable = false;
 604   if (runtime_value == nullptr) {
 605     if (_archived_value != nullptr) {
 606       AOTMetaspace::report_loading_error("Mismatched values for property %s: %s specified during dump time but not during runtime", _prop, _archived_value);
 607       disable = true;
 608     }
 609   } else {
 610     if (_archived_value == nullptr) {
 611       AOTMetaspace::report_loading_error("Mismatched values for property %s: %s specified during runtime but not during dump time", _prop, runtime_value);
 612       disable = true;
 613     } else if (strcmp(runtime_value, _archived_value) != 0) {
 614       AOTMetaspace::report_loading_error("Mismatched values for property %s: runtime %s dump time %s", _prop, runtime_value, _archived_value);
 615       disable = true;
 616     }
 617   }
 618 
 619   if (disable) {
 620     AOTMetaspace::report_loading_error("Disabling optimized module handling");
 621     CDSConfig::stop_using_optimized_module_handling();
 622   }
 623 }
 624 
 625 
 626 static int compare_module_names(const char** p1, const char** p2) {
 627   return strcmp(*p1, *p2);
 628 }
 629 
 630 // Caller needs ResourceMark
 631 const char* Modules::ArchivedProperty::get_numbered_property_as_sorted_string() const {
 632   assert(_numbered, "sanity");
 633   // theoretical string size limit for decimal int, but the following loop will end much sooner due to
 634   // OS command-line size limit.
 635   const int max_digits = 10;
 636   const int extra_symbols_count = 2; // includes '.', '\0'
 637   size_t prop_len = strlen(_prop) + max_digits + extra_symbols_count;
 638   char* prop_name = resource_allocate_bytes(prop_len);
 639   GrowableArray<const char*> list;
 640   for (unsigned int i = 0;; i++) {
 641     jio_snprintf(prop_name, prop_len, "%s.%d", _prop, i);
 642     const char* prop_value = Arguments::get_property(prop_name);
 643     if (prop_value == nullptr) {
 644       break;
 645     }
 646     char* p = ResourceArea::strdup(prop_value);
 647     while (*p == ',') p++; // skip leading commas
 648     while (*p) {
 649       char* next = strchr(p, ',');
 650       if (next == nullptr) {
 651         // no more commas, p is the last element
 652         list.append(p);
 653         break;
 654       } else {
 655         *next = 0;
 656         list.append(p);
 657         p = next + 1;
 658       }
 659     }
 660   }
 661 
 662   // Example:
 663   // --add-modules=java.compiler --add-modules=java.base,java.base,,
 664   //
 665   // list[0] = "java.compiler"
 666   // list[1] = "java.base"
 667   // list[2] = "java.base"
 668   // list[3] = ""
 669   // list[4] = ""
 670   list.sort(compare_module_names);
 671 
 672   const char* prefix = "";
 673   stringStream st;
 674   const char* last_string = ""; // This also filters out all empty strings
 675   for (int i = 0; i < list.length(); i++) {
 676     const char* m = list.at(i);
 677     if (strcmp(m, last_string) != 0) { // filter out duplicates
 678       st.print("%s%s", prefix, m);
 679       last_string = m;
 680       prefix = ",";
 681     }
 682   }
 683 
 684   return (st.size() > 0) ? st.as_string() : nullptr;  // Example: "java.base,java.compiler"
 685 }
 686 
 687 void Modules::dump_archived_module_info() {
 688   for (size_t i = 0; i < num_archived_props(); i++) {
 689     archived_prop(i).dump();
 690   }
 691 }
 692 
 693 void Modules::serialize_archived_module_info(SerializeClosure* soc) {
 694   for (size_t i = 0; i < num_archived_props(); i++) {
 695     archived_prop(i).serialize(soc);
 696   }
 697   if (soc->reading()) {
 698     aot_log_info(aot)("optimized module handling: %s", CDSConfig::is_using_optimized_module_handling() ? "enabled" : "disabled");
 699     aot_log_info(aot)("full module graph: %s", CDSConfig::is_using_full_module_graph() ? "enabled" : "disabled");
 700   }
 701 }
 702 
 703 void Modules::define_archived_modules(Handle h_platform_loader, Handle h_system_loader, TRAPS) {
 704   assert(CDSConfig::is_using_full_module_graph(), "must be");
 705 
 706   // We don't want the classes used by the archived full module graph to be redefined by JVMTI.
 707   // Luckily, such classes are loaded in the JVMTI "early" phase, and CDS is disabled if a JVMTI
 708   // agent wants to redefine classes in this phase.
 709   JVMTI_ONLY(assert(JvmtiExport::is_early_phase(), "must be"));
 710   assert(!(JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()),
 711          "CDS should be disabled if early class hooks are enabled");
 712 
 713   Handle java_base_module(THREAD, ClassLoaderDataShared::restore_archived_oops_for_null_class_loader_data());
 714   // Patch any previously loaded class's module field with java.base's java.lang.Module.
 715   ModuleEntryTable::patch_javabase_entries(THREAD, java_base_module);
 716 
 717   if (h_platform_loader.is_null()) {
 718     THROW_MSG(vmSymbols::java_lang_NullPointerException(), "Null platform loader object");
 719   }
 720 
 721   if (h_system_loader.is_null()) {
 722     THROW_MSG(vmSymbols::java_lang_NullPointerException(), "Null system loader object");
 723   }
 724 
 725   ClassLoaderData* platform_loader_data = SystemDictionary::register_loader(h_platform_loader);
 726   SystemDictionary::set_platform_loader(platform_loader_data);
 727   ClassLoaderDataShared::restore_java_platform_loader_from_archive(platform_loader_data);
 728 
 729   ClassLoaderData* system_loader_data = SystemDictionary::register_loader(h_system_loader);
 730   SystemDictionary::set_system_loader(system_loader_data);
 731   // system_loader_data here is always an instance of jdk.internal.loader.ClassLoader$AppClassLoader.
 732   // However, if -Djava.system.class.loader=xxx is specified, java_platform_loader() would
 733   // be an instance of a user-defined class, so make sure this never happens.
 734   assert(Arguments::get_property("java.system.class.loader") == nullptr,
 735            "archived full module should have been disabled if -Djava.system.class.loader is specified");
 736   ClassLoaderDataShared::restore_java_system_loader_from_archive(system_loader_data);
 737 }
 738 
 739 void Modules::check_cds_restrictions(Handle module1, Handle module2, TRAPS) {
 740   if (CDSConfig::is_dumping_full_module_graph() && Universe::is_module_initialized()) {
 741     if (CDSConfig::is_dumping_dynamic_proxies() && (is_dynamic_proxy_module(module1) || is_dynamic_proxy_module(module2))) {
 742       // The only the we allow is to add or modify the jdk.proxy?? modules that are used for dynamic proxies.
 743     } else {
 744       THROW_MSG(vmSymbols::java_lang_UnsupportedOperationException(),
 745                 "During -Xshare:dump, module system cannot be modified after it's initialized");
 746     }
 747   }
 748 }
 749 
 750 #endif // INCLUDE_CDS_JAVA_HEAP
 751 
 752 bool Modules::is_dynamic_proxy_module(Handle module) {
 753   if (!module.is_null()) {
 754     ModuleEntry* module_entry = java_lang_Module::module_entry(module());
 755     return is_dynamic_proxy_module(module_entry);
 756   }
 757   return false;
 758 }
 759 
 760 bool Modules::is_dynamic_proxy_module(ModuleEntry* module_entry) {
 761   return (module_entry != nullptr && module_entry->is_named() && module_entry->name()->starts_with("jdk.proxy"));
 762 }
 763 
 764 void Modules::set_bootloader_unnamed_module(Handle module, TRAPS) {
 765   ResourceMark rm(THREAD);
 766 
 767   if (module.is_null()) {
 768     THROW_MSG(vmSymbols::java_lang_NullPointerException(), "Null module object");
 769   }
 770   if (!java_lang_Module::is_instance(module())) {
 771     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
 772               "module is not an instance of type java.lang.Module");
 773   }
 774 
 775   // Ensure that this is an unnamed module
 776   oop name = java_lang_Module::name(module());
 777   if (name != nullptr) {
 778     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
 779               "boot loader's unnamed module's java.lang.Module has a name");
 780   }
 781 
 782   // Validate java_base's loader is the boot loader.
 783   oop loader = java_lang_Module::loader(module());
 784   if (loader != nullptr) {
 785     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
 786               "Class loader must be the boot class loader");
 787   }
 788 
 789   log_debug(module)("set_bootloader_unnamed_module(): recording unnamed module for boot loader");
 790 
 791   // Set java.lang.Module for the boot loader's unnamed module
 792   ClassLoaderData* boot_loader_data = ClassLoaderData::the_null_class_loader_data();
 793   ModuleEntry* unnamed_module = boot_loader_data->unnamed_module();
 794   assert(unnamed_module != nullptr, "boot loader's unnamed ModuleEntry not defined");
 795 
 796 #if INCLUDE_CDS_JAVA_HEAP
 797   if (CDSConfig::is_using_full_module_graph()) {
 798     precond(unnamed_module == ClassLoaderDataShared::archived_boot_unnamed_module());
 799     unnamed_module->restore_archived_oops(boot_loader_data);
 800   } else
 801 #endif
 802   {
 803     unnamed_module->set_module_handle(boot_loader_data->add_handle(module));
 804     // Store pointer to the ModuleEntry in the unnamed module's java.lang.Module object.
 805     java_lang_Module::set_module_entry(module(), unnamed_module);
 806   }
 807 }
 808 
 809 void Modules::add_module_exports(Handle from_module, jstring package_name, Handle to_module, TRAPS) {
 810   check_cds_restrictions(from_module, to_module, CHECK);
 811 
 812   if (package_name == nullptr) {
 813     THROW_MSG(vmSymbols::java_lang_NullPointerException(),
 814               "package is null");
 815   }
 816   if (from_module.is_null()) {
 817     THROW_MSG(vmSymbols::java_lang_NullPointerException(),
 818               "from_module is null");
 819   }
 820   ModuleEntry* from_module_entry = get_module_entry(from_module, CHECK);
 821   if (from_module_entry == nullptr) {
 822     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
 823               "from_module cannot be found");
 824   }
 825 
 826   // All packages in unnamed and open modules are exported by default.
 827   if (!from_module_entry->is_named() || from_module_entry->is_open()) return;
 828 
 829   ModuleEntry* to_module_entry;
 830   if (to_module.is_null()) {
 831     to_module_entry = nullptr;  // It's an unqualified export.
 832   } else {
 833     to_module_entry = get_module_entry(to_module, CHECK);
 834     if (to_module_entry == nullptr) {
 835       THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
 836                 "to_module is invalid");
 837     }
 838   }
 839 
 840   PackageEntry* package_entry = nullptr;
 841   char buf[128];
 842   int package_len;
 843 
 844   ResourceMark rm(THREAD);
 845   const char* pkg = as_internal_package(JNIHandles::resolve_non_null(package_name), buf, sizeof(buf), package_len);
 846   {
 847     MutexLocker ml(THREAD, Module_lock);
 848     package_entry = get_locked_package_entry(from_module_entry, pkg, package_len);
 849     // Do nothing if modules are the same
 850     // If the package is not found we'll throw an exception later
 851     if (from_module_entry != to_module_entry &&
 852         package_entry != nullptr) {
 853       package_entry->set_exported(to_module_entry);
 854     }
 855   }
 856 
 857   // Handle errors and logging outside locked section
 858   if (package_entry == nullptr) {
 859     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
 860               err_msg("Package %s not found in from_module %s",
 861                       pkg != nullptr ? pkg : "",
 862                       from_module_entry->name()->as_C_string()));
 863   }
 864 
 865   if (log_is_enabled(Debug, module)) {
 866     log_debug(module)("add_module_exports(): package %s in module %s is exported to module %s",
 867                       package_entry->name()->as_C_string(),
 868                       from_module_entry->name()->as_C_string(),
 869                       to_module_entry == nullptr ? "null" :
 870                       to_module_entry->is_named() ?
 871                       to_module_entry->name()->as_C_string() : UNNAMED_MODULE);
 872   }
 873 }
 874 
 875 
 876 void Modules::add_module_exports_qualified(Handle from_module, jstring package,
 877                                            Handle to_module, TRAPS) {
 878   check_cds_restrictions(from_module, to_module, CHECK);
 879   if (to_module.is_null()) {
 880     THROW_MSG(vmSymbols::java_lang_NullPointerException(),
 881               "to_module is null");
 882   }
 883   add_module_exports(from_module, package, to_module, CHECK);
 884 }
 885 
 886 void Modules::add_reads_module(Handle from_module, Handle to_module, TRAPS) {
 887   check_cds_restrictions(from_module, to_module, CHECK);
 888   if (from_module.is_null()) {
 889     THROW_MSG(vmSymbols::java_lang_NullPointerException(),
 890               "from_module is null");
 891   }
 892 
 893   ModuleEntry* from_module_entry = get_module_entry(from_module, CHECK);
 894   if (from_module_entry == nullptr) {
 895     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
 896               "from_module is not valid");
 897   }
 898 
 899   ModuleEntry* to_module_entry;
 900   if (!to_module.is_null()) {
 901     to_module_entry = get_module_entry(to_module, CHECK);
 902     if (to_module_entry == nullptr) {
 903       THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
 904                 "to_module is invalid");
 905     }
 906   } else {
 907     to_module_entry = nullptr;
 908   }
 909 
 910   ResourceMark rm(THREAD);
 911   log_debug(module)("add_reads_module(): Adding read from module %s to module %s",
 912                     from_module_entry->is_named() ?
 913                     from_module_entry->name()->as_C_string() : UNNAMED_MODULE,
 914                     to_module_entry == nullptr ? "all unnamed" :
 915                       (to_module_entry->is_named() ?
 916                        to_module_entry->name()->as_C_string() : UNNAMED_MODULE));
 917 
 918   // if modules are the same or if from_module is unnamed then no need to add the read.
 919   if (from_module_entry != to_module_entry && from_module_entry->is_named()) {
 920     from_module_entry->add_read(to_module_entry);
 921   }
 922 }
 923 
 924 // This method is called by JFR and JNI.
 925 jobject Modules::get_module(jclass clazz, TRAPS) {
 926   assert(ModuleEntryTable::javabase_defined(),
 927          "Attempt to call get_module before " JAVA_BASE_NAME " is defined");
 928 
 929   if (clazz == nullptr) {
 930     THROW_MSG_(vmSymbols::java_lang_NullPointerException(),
 931                "class is null", nullptr);
 932   }
 933   oop mirror = JNIHandles::resolve_non_null(clazz);
 934   if (mirror == nullptr) {
 935     log_debug(module)("get_module(): no mirror, returning nullptr");
 936     return nullptr;
 937   }
 938   if (!java_lang_Class::is_instance(mirror)) {
 939     THROW_MSG_(vmSymbols::java_lang_IllegalArgumentException(),
 940                "Invalid class", nullptr);
 941   }
 942 
 943   oop module = java_lang_Class::module(mirror);
 944 
 945   assert(module != nullptr, "java.lang.Class module field not set");
 946   assert(java_lang_Module::is_instance(module), "module is not an instance of type java.lang.Module");
 947 
 948   LogTarget(Debug,module) lt;
 949   if (lt.is_enabled()) {
 950     LogStream ls(lt);
 951     Klass* klass = java_lang_Class::as_Klass(mirror);
 952     oop module_name = java_lang_Module::name(module);
 953     if (module_name != nullptr) {
 954       ls.print("get_module(): module ");
 955       java_lang_String::print(module_name, tty);
 956     } else {
 957       ls.print("get_module(): Unnamed Module");
 958     }
 959     if (klass != nullptr) {
 960       ResourceMark rm(THREAD);
 961       ls.print_cr(" for class %s", klass->external_name());
 962     } else {
 963       ls.print_cr(" for primitive class");
 964     }
 965   }
 966 
 967   return JNIHandles::make_local(THREAD, module);
 968 }
 969 
 970 oop Modules::get_named_module(Handle h_loader, const char* package_name) {
 971   assert(ModuleEntryTable::javabase_defined(),
 972          "Attempt to call get_named_module before " JAVA_BASE_NAME " is defined");
 973   assert(h_loader.is_null() || java_lang_ClassLoader::is_subclass(h_loader->klass()),
 974          "Class loader is not a subclass of java.lang.ClassLoader");
 975   assert(package_name != nullptr, "the package_name should not be null");
 976 
 977   if (strlen(package_name) == 0) {
 978     return nullptr;
 979   }
 980   TempNewSymbol package_sym = SymbolTable::new_symbol(package_name);
 981   const PackageEntry* const pkg_entry =
 982     get_package_entry_by_name(package_sym, h_loader);
 983   const ModuleEntry* const module_entry = (pkg_entry != nullptr ? pkg_entry->module() : nullptr);
 984 
 985   if (module_entry != nullptr && module_entry->module_oop() != nullptr && module_entry->is_named()) {
 986     return module_entry->module_oop();
 987   }
 988   return nullptr;
 989 }
 990 
 991 // Export package in module to all unnamed modules.
 992 void Modules::add_module_exports_to_all_unnamed(Handle module, jstring package_name, TRAPS) {
 993   check_cds_restrictions(Handle(), module, CHECK);
 994   if (module.is_null()) {
 995     THROW_MSG(vmSymbols::java_lang_NullPointerException(),
 996               "module is null");
 997   }
 998   if (package_name == nullptr) {
 999     THROW_MSG(vmSymbols::java_lang_NullPointerException(),
1000               "package is null");
1001   }
1002   ModuleEntry* module_entry = get_module_entry(module, CHECK);
1003   if (module_entry == nullptr) {
1004     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
1005               "module is invalid");
1006   }
1007 
1008   // No-op for unnamed module and open modules
1009   if (!module_entry->is_named() || module_entry->is_open())
1010     return;
1011 
1012   ResourceMark rm(THREAD);
1013   char buf[128];
1014   int pkg_len;
1015   const char* pkg = as_internal_package(JNIHandles::resolve_non_null(package_name), buf, sizeof(buf), pkg_len);
1016   PackageEntry* package_entry = nullptr;
1017   {
1018     MutexLocker m1(THREAD, Module_lock);
1019     package_entry = get_locked_package_entry(module_entry, pkg, pkg_len);
1020 
1021     // Mark package as exported to all unnamed modules.
1022     if (package_entry != nullptr) {
1023       package_entry->set_is_exported_allUnnamed();
1024     }
1025   }
1026 
1027   // Handle errors and logging outside locked section
1028   if (package_entry == nullptr) {
1029     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
1030               err_msg("Package %s not found in module %s",
1031                       pkg != nullptr ? pkg : "",
1032                       module_entry->name()->as_C_string()));
1033   }
1034 
1035   if (log_is_enabled(Debug, module)) {
1036     log_debug(module)("add_module_exports_to_all_unnamed(): package %s in module"
1037                       " %s is exported to all unnamed modules",
1038                        package_entry->name()->as_C_string(),
1039                        module_entry->name()->as_C_string());
1040   }
1041 }