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/archiveBuilder.hpp"
26 #include "cds/cdsConfig.hpp"
27 #include "cds/metaspaceShared.hpp"
28 #include "classfile/classFileParser.hpp"
29 #include "classfile/classLoader.hpp"
30 #include "classfile/classLoaderData.inline.hpp"
31 #include "classfile/classLoaderDataShared.hpp"
32 #include "classfile/classLoaderExt.hpp"
33 #include "classfile/javaAssertions.hpp"
34 #include "classfile/javaClasses.hpp"
35 #include "classfile/javaClasses.inline.hpp"
36 #include "classfile/moduleEntry.hpp"
37 #include "classfile/modules.hpp"
38 #include "classfile/packageEntry.hpp"
39 #include "classfile/stringTable.hpp"
40 #include "classfile/symbolTable.hpp"
41 #include "classfile/systemDictionary.hpp"
42 #include "classfile/vmClasses.hpp"
43 #include "classfile/vmSymbols.hpp"
44 #include "jvm.h"
45 #include "logging/log.hpp"
46 #include "logging/logStream.hpp"
47 #include "memory/resourceArea.hpp"
48 #include "prims/jvmtiExport.hpp"
49 #include "runtime/arguments.hpp"
50 #include "runtime/globals_extension.hpp"
51 #include "runtime/handles.inline.hpp"
52 #include "runtime/javaCalls.hpp"
53 #include "runtime/jniHandles.inline.hpp"
54 #include "utilities/formatBuffer.hpp"
55 #include "utilities/stringUtils.hpp"
56 #include "utilities/utf8.hpp"
57
58 static bool verify_module_name(const char *module_name, int len) {
59 assert(module_name != nullptr, "invariant");
60 return (len > 0 && len <= Symbol::max_length());
61 }
62
63 static bool verify_package_name(const char* package_name, int len) {
64 assert(package_name != nullptr, "Package name derived from non-null jstring can't be null");
65 return (len > 0 && len <= Symbol::max_length() &&
66 ClassFileParser::verify_unqualified_name(package_name, len,
67 ClassFileParser::LegalClass));
68 }
69
70 static char* get_module_name(oop module, int& len, TRAPS) {
71 oop name_oop = java_lang_Module::name(module);
72 if (name_oop == nullptr) {
73 THROW_MSG_NULL(vmSymbols::java_lang_NullPointerException(), "Null module name");
74 }
75 size_t utf8_len;
76 char* module_name = java_lang_String::as_utf8_string(name_oop, utf8_len);
77 len = checked_cast<int>(utf8_len); // module names are < 64K
78 if (!verify_module_name(module_name, len)) {
79 THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(),
80 err_msg("Invalid module name: %s", module_name));
81 }
82 return module_name;
83 }
84
85 static Symbol* as_symbol(jstring str_object) {
86 if (str_object == nullptr) {
87 return nullptr;
88 }
89 size_t len;
90 char* str = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(str_object), len);
91 return SymbolTable::new_symbol(str, checked_cast<int>(len));
92 }
93
94 ModuleEntryTable* Modules::get_module_entry_table(Handle h_loader) {
95 // This code can be called during start-up, before the classLoader's classLoader data got
96 // created. So, call register_loader() to make sure the classLoader data gets created.
97 ClassLoaderData *loader_cld = SystemDictionary::register_loader(h_loader);
98 return loader_cld->modules();
99 }
100
101 static PackageEntryTable* get_package_entry_table(Handle h_loader) {
102 // This code can be called during start-up, before the classLoader's classLoader data got
103 // created. So, call register_loader() to make sure the classLoader data gets created.
104 ClassLoaderData *loader_cld = SystemDictionary::register_loader(h_loader);
105 return loader_cld->packages();
106 }
107
108 static ModuleEntry* get_module_entry(Handle module, TRAPS) {
109 if (!java_lang_Module::is_instance(module())) {
110 THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(),
111 "module is not an instance of type java.lang.Module");
112 }
113 return java_lang_Module::module_entry(module());
114 }
115
116
117 static PackageEntry* get_locked_package_entry(ModuleEntry* module_entry, const char* package_name, int len) {
118 assert(Module_lock->owned_by_self(), "should have the Module_lock");
119 assert(package_name != nullptr, "Precondition");
120 TempNewSymbol pkg_symbol = SymbolTable::new_symbol(package_name, len);
121 PackageEntryTable* package_entry_table = module_entry->loader_data()->packages();
122 assert(package_entry_table != nullptr, "Unexpected null package entry table");
123 PackageEntry* package_entry = package_entry_table->locked_lookup_only(pkg_symbol);
124 assert(package_entry == nullptr || package_entry->module() == module_entry, "Unexpectedly found a package linked to another module");
125 return package_entry;
126 }
127
128 static PackageEntry* get_package_entry_by_name(Symbol* package, Handle h_loader) {
129 if (package != nullptr) {
130 PackageEntryTable* const package_entry_table =
131 get_package_entry_table(h_loader);
132 assert(package_entry_table != nullptr, "Unexpected null package entry table");
133 return package_entry_table->lookup_only(package);
134 }
135 return nullptr;
136 }
137
138 bool Modules::is_package_defined(Symbol* package, Handle h_loader) {
139 PackageEntry* res = get_package_entry_by_name(package, h_loader);
140 return res != nullptr;
141 }
142
143 // Converts the String oop to an internal package
144 // Will use the provided buffer if it's sufficiently large, otherwise allocates
145 // a resource array
146 // The length of the resulting string will be assigned to utf8_len
147 static const char* as_internal_package(oop package_string, char* buf, size_t buflen, int& utf8_len) {
148 size_t full_utf8_len;
149 char* package_name = java_lang_String::as_utf8_string_full(package_string, buf, buflen, full_utf8_len);
150 utf8_len = checked_cast<int>(full_utf8_len); // package names are < 64K
151
152 // Turn all '/'s into '.'s
153 for (int index = 0; index < utf8_len; index++) {
154 if (package_name[index] == JVM_SIGNATURE_DOT) {
155 package_name[index] = JVM_SIGNATURE_SLASH;
156 }
157 }
158 return package_name;
159 }
160
161 static void define_javabase_module(Handle module_handle, jstring version, jstring location,
162 objArrayHandle pkgs, int num_packages, TRAPS) {
163 ResourceMark rm(THREAD);
164
165 // Obtain java.base's module version
166 TempNewSymbol version_symbol = as_symbol(version);
167
168 // Obtain java.base's location
169 TempNewSymbol location_symbol = as_symbol(location);
170
171 // Check that the packages are syntactically ok.
172 char buf[128];
173 GrowableArray<Symbol*>* pkg_list = new GrowableArray<Symbol*>(num_packages);
174 for (int x = 0; x < num_packages; x++) {
175 oop pkg_str = pkgs->obj_at(x);
176
177 if (pkg_str == nullptr || pkg_str->klass() != vmClasses::String_klass()) {
178 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
179 err_msg("Bad package name"));
180 }
181
182 int package_len;
183 const char* package_name = as_internal_package(pkg_str, buf, sizeof(buf), package_len);
184 if (!verify_package_name(package_name, package_len)) {
185 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
186 err_msg("Invalid package name: %s for module: " JAVA_BASE_NAME, package_name));
187 }
188 Symbol* pkg_symbol = SymbolTable::new_symbol(package_name, package_len);
189 pkg_list->append(pkg_symbol);
190 }
191
192 // Validate java_base's loader is the boot loader.
193 oop loader = java_lang_Module::loader(module_handle());
194 if (loader != nullptr) {
195 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
196 "Class loader must be the boot class loader");
197 }
198 Handle h_loader(THREAD, loader);
199
200 // Ensure the boot loader's PackageEntryTable has been created
201 PackageEntryTable* package_table = get_package_entry_table(h_loader);
202 assert(pkg_list->length() == 0 || package_table != nullptr, "Bad package_table");
203
204 // Ensure java.base's ModuleEntry has been created
205 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, "No ModuleEntry for " JAVA_BASE_NAME);
206
207 bool duplicate_javabase = false;
208 {
209 MutexLocker m1(THREAD, Module_lock);
210
211 if (ModuleEntryTable::javabase_defined()) {
212 duplicate_javabase = true;
213 } else {
214
215 // Verify that all java.base packages created during bootstrapping are in
216 // pkg_list. If any are not in pkg_list, than a non-java.base class was
217 // loaded erroneously pre java.base module definition.
218 package_table->verify_javabase_packages(pkg_list);
219
220 // loop through and add any new packages for java.base
221 for (int x = 0; x < pkg_list->length(); x++) {
222 // Some of java.base's packages were added early in bootstrapping, ignore duplicates.
223 package_table->locked_create_entry_if_absent(pkg_list->at(x),
224 ModuleEntryTable::javabase_moduleEntry());
225 assert(package_table->locked_lookup_only(pkg_list->at(x)) != nullptr,
226 "Unable to create a " JAVA_BASE_NAME " package entry");
227 // Unable to have a GrowableArray of TempNewSymbol. Must decrement the refcount of
228 // the Symbol* that was created above for each package. The refcount was incremented
229 // by SymbolTable::new_symbol and as well by the PackageEntry creation.
230 pkg_list->at(x)->decrement_refcount();
231 }
232
233 // Finish defining java.base's ModuleEntry
234 ModuleEntryTable::finalize_javabase(module_handle, version_symbol, location_symbol);
235 }
236 }
237 if (duplicate_javabase) {
238 THROW_MSG(vmSymbols::java_lang_InternalError(),
239 "Module " JAVA_BASE_NAME " is already defined");
240 }
241
242 // Only the thread that actually defined the base module will get here,
243 // so no locking is needed.
244
245 // Patch any previously loaded class's module field with java.base's java.lang.Module.
246 ModuleEntryTable::patch_javabase_entries(THREAD, module_handle);
247
248 log_info(module, load)(JAVA_BASE_NAME " location: %s",
249 location_symbol != nullptr ? location_symbol->as_C_string() : "nullptr");
250 log_debug(module)("define_javabase_module(): Definition of module: "
251 JAVA_BASE_NAME ", version: %s, location: %s, package #: %d",
252 version_symbol != nullptr ? version_symbol->as_C_string() : "nullptr",
253 location_symbol != nullptr ? location_symbol->as_C_string() : "nullptr",
254 pkg_list->length());
255
256 // packages defined to java.base
257 if (log_is_enabled(Trace, module)) {
258 for (int x = 0; x < pkg_list->length(); x++) {
259 log_trace(module)("define_javabase_module(): creation of package %s for module " JAVA_BASE_NAME,
260 (pkg_list->at(x))->as_C_string());
261 }
262 }
263 }
264
265 // Caller needs ResourceMark.
266 static void throw_dup_pkg_exception(const char* module_name, PackageEntry* package, TRAPS) {
267 const char* package_name = package->name()->as_C_string();
268 if (package->module()->is_named()) {
269 THROW_MSG(vmSymbols::java_lang_IllegalStateException(),
270 err_msg("Package %s for module %s is already in another module, %s, defined to the class loader",
271 package_name, module_name, package->module()->name()->as_C_string()));
272 } else {
273 THROW_MSG(vmSymbols::java_lang_IllegalStateException(),
274 err_msg("Package %s for module %s is already in the unnamed module defined to the class loader",
275 package_name, module_name));
276 }
277 }
278
279 void Modules::define_module(Handle module, jboolean is_open, jstring version,
280 jstring location, jobjectArray packages, TRAPS) {
281 ResourceMark rm(THREAD);
282
283 if (module.is_null()) {
284 THROW_MSG(vmSymbols::java_lang_NullPointerException(), "Null module object");
285 }
286
287 if (!java_lang_Module::is_instance(module())) {
288 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
289 "module is not an instance of type java.lang.Module");
290 }
291
292 int module_name_len;
293 char* module_name = get_module_name(module(), module_name_len, CHECK);
294 if (module_name == nullptr) {
295 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
296 "Module name cannot be null");
297 }
298
299 // Resolve packages
300 objArrayHandle packages_h(THREAD, objArrayOop(JNIHandles::resolve(packages)));
301 int num_packages = (packages_h.is_null() ? 0 : packages_h->length());
302 if (strncmp(module_name, "jdk.proxy", 9) != 0) {
303 check_cds_restrictions(Handle(), Handle(), CHECK);
304 }
305
306 // Special handling of java.base definition
307 if (strcmp(module_name, JAVA_BASE_NAME) == 0) {
308 assert(is_open == JNI_FALSE, "java.base module cannot be open");
309 define_javabase_module(module, version, location, packages_h, num_packages, CHECK);
310 return;
311 }
312
313 oop loader = java_lang_Module::loader(module());
314 Handle h_loader = Handle(THREAD, loader);
315 // define_module can be called during start-up, before the class loader's ClassLoaderData
316 // has been created. SystemDictionary::register_loader ensures creation, if needed.
317 ClassLoaderData* loader_data = SystemDictionary::register_loader(h_loader);
318 assert(loader_data != nullptr, "class loader data shouldn't be null");
319
320 // Only modules defined to either the boot or platform class loader, can define a "java/" package.
321 bool java_pkg_disallowed = !h_loader.is_null() &&
322 !SystemDictionary::is_platform_class_loader(h_loader());
323
324 // Check that the list of packages has no duplicates and that the
325 // packages are syntactically ok.
326 char buf[128];
327 GrowableArray<Symbol*>* pkg_list = new GrowableArray<Symbol*>(num_packages);
328 for (int x = 0; x < num_packages; x++) {
329 oop pkg_str = packages_h->obj_at(x);
330 if (pkg_str == nullptr || pkg_str->klass() != vmClasses::String_klass()) {
331 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
332 err_msg("Bad package name"));
333 }
334
335 int package_len;
336 const char* package_name = as_internal_package(pkg_str, buf, sizeof(buf), package_len);
337 if (!verify_package_name(package_name, package_len)) {
338 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
339 err_msg("Invalid package name: %s for module: %s",
340 package_name, module_name));
341 }
342
343 // Only modules defined to either the boot or platform class loader, can define a "java/" package.
344 if (java_pkg_disallowed &&
345 (strncmp(package_name, JAVAPKG, JAVAPKG_LEN) == 0 &&
346 (package_name[JAVAPKG_LEN] == JVM_SIGNATURE_SLASH || package_name[JAVAPKG_LEN] == '\0'))) {
347 const char* class_loader_name = loader_data->loader_name_and_id();
348 size_t pkg_len = strlen(package_name);
349 char* pkg_name = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, pkg_len + 1);
350 strncpy(pkg_name, package_name, pkg_len + 1);
351 StringUtils::replace_no_expand(pkg_name, "/", ".");
352 const char* msg_text1 = "Class loader (instance of): ";
353 const char* msg_text2 = " tried to define prohibited package name: ";
354 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + pkg_len + 1;
355 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
356 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, pkg_name);
357 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), message);
358 }
359
360 Symbol* pkg_symbol = SymbolTable::new_symbol(package_name, package_len);
361 pkg_list->append(pkg_symbol);
362 }
363
364 ModuleEntryTable* module_table = get_module_entry_table(h_loader);
365 assert(module_table != nullptr, "module entry table shouldn't be null");
366
367 // Create symbol* entry for module name.
368 TempNewSymbol module_symbol = SymbolTable::new_symbol(module_name, module_name_len);
369
370 bool dupl_modules = false;
371
372 // Create symbol for module version.
373 TempNewSymbol version_symbol = as_symbol(version);
374
375 // Create symbol* entry for module location.
376 TempNewSymbol location_symbol = as_symbol(location);
377
378 PackageEntryTable* package_table = nullptr;
379 PackageEntry* existing_pkg = nullptr;
380 {
381 MutexLocker ml(THREAD, Module_lock);
382
383 if (num_packages > 0) {
384 package_table = get_package_entry_table(h_loader);
385 assert(package_table != nullptr, "Missing package_table");
386
387 // Check that none of the packages exist in the class loader's package table.
388 for (int x = 0; x < pkg_list->length(); x++) {
389 existing_pkg = package_table->locked_lookup_only(pkg_list->at(x));
390 if (existing_pkg != nullptr) {
391 // This could be because the module was already defined. If so,
392 // report that error instead of the package error.
393 if (module_table->lookup_only(module_symbol) != nullptr) {
394 dupl_modules = true;
395 }
396 break;
397 }
398 }
399 } // if (num_packages > 0)...
400
401 // Add the module and its packages.
402 if (!dupl_modules && existing_pkg == nullptr) {
403 if (module_table->lookup_only(module_symbol) == nullptr) {
404 // Create the entry for this module in the class loader's module entry table.
405 ModuleEntry* module_entry = module_table->locked_create_entry(module,
406 (is_open == JNI_TRUE), module_symbol,
407 version_symbol, location_symbol, loader_data);
408 assert(module_entry != nullptr, "module_entry creation failed");
409
410 // Add the packages.
411 assert(pkg_list->length() == 0 || package_table != nullptr, "Bad package table");
412 for (int y = 0; y < pkg_list->length(); y++) {
413 package_table->locked_create_entry(pkg_list->at(y), module_entry);
414
415 // Unable to have a GrowableArray of TempNewSymbol. Must decrement the refcount of
416 // the Symbol* that was created above for each package. The refcount was incremented
417 // by SymbolTable::new_symbol and as well by the PackageEntry creation.
418 pkg_list->at(y)->decrement_refcount();
419 }
420
421 // Store pointer to ModuleEntry record in java.lang.Module object.
422 java_lang_Module::set_module_entry(module(), module_entry);
423 } else {
424 dupl_modules = true;
425 }
426 }
427 } // Release the lock
428
429 // any errors ?
430 if (dupl_modules) {
431 THROW_MSG(vmSymbols::java_lang_IllegalStateException(),
432 err_msg("Module %s is already defined", module_name));
433 } else if (existing_pkg != nullptr) {
434 throw_dup_pkg_exception(module_name, existing_pkg, CHECK);
435 }
436
437 log_info(module, load)("%s location: %s", module_name,
438 location_symbol != nullptr ? location_symbol->as_C_string() : "null");
439 LogTarget(Debug, module) lt;
440 if (lt.is_enabled()) {
441 LogStream ls(lt);
442 ls.print("define_module(): creation of module: %s, version: %s, location: %s, ",
443 module_name, version_symbol != nullptr ? version_symbol->as_C_string() : "null",
444 location_symbol != nullptr ? location_symbol->as_C_string() : "null");
445 loader_data->print_value_on(&ls);
446 ls.print_cr(", package #: %d", pkg_list->length());
447 for (int y = 0; y < pkg_list->length(); y++) {
448 log_trace(module)("define_module(): creation of package %s for module %s",
449 (pkg_list->at(y))->as_C_string(), module_name);
450 }
451 }
452
453 // If the module is defined to the boot loader and an exploded build is being
454 // used, prepend <java.home>/modules/modules_name to the boot class path.
455 if (h_loader.is_null() && !ClassLoader::has_jrt_entry()) {
456 ClassLoader::add_to_exploded_build_list(THREAD, module_symbol);
457 }
458
459 #if COMPILER2_OR_JVMCI
460 // Special handling of jdk.incubator.vector
461 if (strcmp(module_name, "jdk.incubator.vector") == 0) {
462 if (FLAG_IS_DEFAULT(EnableVectorSupport)) {
463 FLAG_SET_DEFAULT(EnableVectorSupport, true);
464 }
465 if (EnableVectorSupport && FLAG_IS_DEFAULT(EnableVectorReboxing)) {
466 FLAG_SET_DEFAULT(EnableVectorReboxing, true);
467 }
468 if (EnableVectorSupport && EnableVectorReboxing && FLAG_IS_DEFAULT(EnableVectorAggressiveReboxing)) {
469 FLAG_SET_DEFAULT(EnableVectorAggressiveReboxing, true);
470 }
471 if (EnableVectorSupport && FLAG_IS_DEFAULT(UseVectorStubs)) {
472 FLAG_SET_DEFAULT(UseVectorStubs, true);
473 }
474 log_info(compilation)("EnableVectorSupport=%s", (EnableVectorSupport ? "true" : "false"));
475 log_info(compilation)("EnableVectorReboxing=%s", (EnableVectorReboxing ? "true" : "false"));
476 log_info(compilation)("EnableVectorAggressiveReboxing=%s", (EnableVectorAggressiveReboxing ? "true" : "false"));
477 log_info(compilation)("UseVectorStubs=%s", (UseVectorStubs ? "true" : "false"));
478 }
479 #endif // COMPILER2_OR_JVMCI
480 }
481
482 #if INCLUDE_CDS_JAVA_HEAP
483 static bool _seen_platform_unnamed_module = false;
484 static bool _seen_system_unnamed_module = false;
485
486 // Validate the states of an java.lang.Module oop to be archived.
487 void Modules::check_archived_module_oop(oop orig_module_obj) {
488 assert(CDSConfig::is_dumping_full_module_graph(), "must be");
489 assert(java_lang_Module::is_instance(orig_module_obj), "must be");
490
491 ModuleEntry* orig_module_ent = java_lang_Module::module_entry_raw(orig_module_obj);
492 if (orig_module_ent == nullptr) {
493 // These special java.lang.Module oops are created in Java code. They are not
494 // defined via Modules::define_module(), so they don't have a ModuleEntry:
495 // java.lang.Module::ALL_UNNAMED_MODULE
496 // java.lang.Module::EVERYONE_MODULE
497 // jdk.internal.loader.ClassLoaders$BootClassLoader::unnamedModule
498 log_info(cds, module)("Archived java.lang.Module oop " PTR_FORMAT " with no ModuleEntry*", p2i(orig_module_obj));
499 assert(java_lang_Module::name(orig_module_obj) == nullptr, "must be unnamed");
500 } else {
501 // This java.lang.Module oop has an ModuleEntry*. Check if the latter is archived.
502 if (log_is_enabled(Info, cds, module)) {
503 ResourceMark rm;
504 LogStream ls(Log(cds, module)::info());
505 ls.print("Archived java.lang.Module oop " PTR_FORMAT " for ", p2i(orig_module_obj));
506 orig_module_ent->print(&ls);
507 }
508
509 // We only archive the default module graph, which should contain only java.lang.Module oops
510 // for the 3 built-in loaders (boot/platform/system)
511 ClassLoaderData* loader_data = orig_module_ent->loader_data();
512 assert(loader_data->is_builtin_class_loader_data(), "must be");
513
514 if (orig_module_ent->name() != nullptr) {
515 // For each named module, we archive both the java.lang.Module oop and the ModuleEntry.
516 assert(orig_module_ent->has_been_archived(), "sanity");
517 } else {
518 // We only archive two unnamed module oops (for platform and system loaders). These do NOT have an archived
519 // ModuleEntry.
520 //
521 // At runtime, these oops are fetched from java_lang_ClassLoader::unnamedModule(loader) and
522 // are initialized in ClassLoaderData::ClassLoaderData() => ModuleEntry::create_unnamed_module(), where
523 // a new ModuleEntry is allocated.
524 assert(!loader_data->is_boot_class_loader_data(), "unnamed module for boot loader should be not archived");
525 assert(!orig_module_ent->has_been_archived(), "sanity");
526
527 if (SystemDictionary::is_platform_class_loader(loader_data->class_loader())) {
528 assert(!_seen_platform_unnamed_module, "only once");
529 _seen_platform_unnamed_module = true;
530 } else if (SystemDictionary::is_system_class_loader(loader_data->class_loader())) {
531 assert(!_seen_system_unnamed_module, "only once");
532 _seen_system_unnamed_module = true;
533 } else {
534 // The java.lang.Module oop and ModuleEntry of the unnamed module of the boot loader are
535 // not in the archived module graph. These are always allocated at runtime.
536 ShouldNotReachHere();
537 }
538 }
539 }
540 }
541
542 void Modules::verify_archived_modules() {
543 ModuleEntry::verify_archived_module_entries();
544 }
545
546 char* Modules::_archived_main_module_name = nullptr;
547 char* Modules::_archived_addmods_names = nullptr;
548 char* Modules::_archived_native_access_flags = nullptr;
549
550 void Modules::dump_main_module_name() {
551 const char* module_name = Arguments::get_property("jdk.module.main");
552 if (module_name != nullptr) {
553 _archived_main_module_name = ArchiveBuilder::current()->ro_strdup(module_name);
554 }
555 }
556
557 void Modules::check_archived_flag_consistency(char* archived_flag, const char* runtime_flag, const char* property) {
558 log_info(cds)("%s %s", property,
559 archived_flag != nullptr ? archived_flag : "(null)");
560 bool disable = false;
561 if (runtime_flag == nullptr) {
562 if (archived_flag != nullptr) {
563 log_info(cds)("Mismatched values for property %s: %s specified during dump time but not during runtime", property, archived_flag);
564 disable = true;
565 }
566 } else {
567 if (archived_flag == nullptr) {
568 log_info(cds)("Mismatched values for property %s: %s specified during runtime but not during dump time", property, runtime_flag);
569 disable = true;
570 } else if (strcmp(runtime_flag, archived_flag) != 0) {
571 log_info(cds)("Mismatched values for property %s: runtime %s dump time %s", property, runtime_flag, archived_flag);
572 disable = true;
573 }
574 }
575
576 if (disable) {
577 log_info(cds)("Disabling optimized module handling");
578 CDSConfig::stop_using_optimized_module_handling();
579 }
580 log_info(cds)("optimized module handling: %s", CDSConfig::is_using_optimized_module_handling() ? "enabled" : "disabled");
581 log_info(cds)("full module graph: %s", CDSConfig::is_using_full_module_graph() ? "enabled" : "disabled");
582 }
583
584 void Modules::dump_archived_module_info() {
585 // Write module name into archive
586 CDS_JAVA_HEAP_ONLY(Modules::dump_main_module_name();)
587 // Write module names from --add-modules into archive
588 CDS_JAVA_HEAP_ONLY(Modules::dump_addmods_names();)
589 // Write native enable-native-access flag into archive
590 CDS_JAVA_HEAP_ONLY(Modules::dump_native_access_flag());
591 }
592
593 void Modules::serialize_archived_module_info(SerializeClosure* soc) {
594 CDS_JAVA_HEAP_ONLY(Modules::serialize(soc);)
595 CDS_JAVA_HEAP_ONLY(Modules::serialize_addmods_names(soc);)
596 CDS_JAVA_HEAP_ONLY(Modules::serialize_native_access_flags(soc);)
597 }
598
599 void Modules::serialize(SerializeClosure* soc) {
600 soc->do_ptr(&_archived_main_module_name);
601 if (soc->reading()) {
602 const char* runtime_main_module = Arguments::get_property("jdk.module.main");
603 log_info(cds)("_archived_main_module_name %s",
604 _archived_main_module_name != nullptr ? _archived_main_module_name : "(null)");
605
606 check_archived_flag_consistency(_archived_main_module_name, runtime_main_module, "jdk.module.main");
607
608 // Don't hold onto the pointer, in case we might decide to unmap the archive.
609 _archived_main_module_name = nullptr;
610 }
611 }
612
613 void Modules::dump_native_access_flag() {
614 ResourceMark rm;
615 const char* native_access_names = get_native_access_flags_as_sorted_string();
616 if (native_access_names != nullptr) {
617 _archived_native_access_flags = ArchiveBuilder::current()->ro_strdup(native_access_names);
618 }
619 }
620
621 // Caller needs ResourceMark
622 const char* Modules::get_native_access_flags_as_sorted_string() {
623 return get_numbered_property_as_sorted_string("jdk.module.enable.native.access");
624 }
625
626 void Modules::serialize_native_access_flags(SerializeClosure* soc) {
627 soc->do_ptr(&_archived_native_access_flags);
628 if (soc->reading()) {
629 ResourceMark rm;
630 check_archived_flag_consistency(_archived_native_access_flags, get_native_access_flags_as_sorted_string(), "jdk.module.enable.native.access");
631
632 // Don't hold onto the pointer, in case we might decide to unmap the archive.
633 _archived_native_access_flags = nullptr;
634 }
635 }
636
637 void Modules::dump_addmods_names() {
638 ResourceMark rm;
639 const char* addmods_names = get_addmods_names_as_sorted_string();
640 if (addmods_names != nullptr) {
641 _archived_addmods_names = ArchiveBuilder::current()->ro_strdup(addmods_names);
642 }
643 }
644
645 // Caller needs ResourceMark
646 const char* Modules::get_addmods_names_as_sorted_string() {
647 return get_numbered_property_as_sorted_string("jdk.module.addmods");
648 }
649
650 void Modules::serialize_addmods_names(SerializeClosure* soc) {
651 soc->do_ptr(&_archived_addmods_names);
652 if (soc->reading()) {
653 ResourceMark rm;
654 check_archived_flag_consistency(_archived_addmods_names, get_addmods_names_as_sorted_string(), "jdk.module.addmods");
655
656 // Don't hold onto the pointer, in case we might decide to unmap the archive.
657 _archived_addmods_names = nullptr;
658 }
659 }
660
661 // Caller needs ResourceMark
662 const char* Modules::get_numbered_property_as_sorted_string(const char* property) {
663 // theoretical string size limit for decimal int, but the following loop will end much sooner due to
664 // OS command-line size limit.
665 const int max_digits = 10;
666 const int extra_symbols_count = 2; // includes '.', '\0'
667 size_t prop_len = strlen(property) + max_digits + extra_symbols_count;
668 char* prop_name = resource_allocate_bytes(prop_len);
669 GrowableArray<const char*> list;
670 for (unsigned int i = 0;; i++) {
671 jio_snprintf(prop_name, prop_len, "%s.%d", property, i);
672 const char* prop_value = Arguments::get_property(prop_name);
673 if (prop_value == nullptr) {
674 break;
675 }
676 char* p = resource_allocate_bytes(strlen(prop_value) + 1);
677 strcpy(p, prop_value);
678 while (*p == ',') p++; // skip leading commas
679 while (*p) {
680 char* next = strchr(p, ',');
681 if (next == nullptr) {
682 // no more commas, p is the last element
683 list.append(p);
684 break;
685 } else {
686 *next = 0;
687 list.append(p);
688 p = next + 1;
689 }
690 }
691 }
692
693 // Example:
694 // --add-modules=java.compiler --add-modules=java.base,java.base,,
695 //
696 // list[0] = "java.compiler"
697 // list[1] = "java.base"
698 // list[2] = "java.base"
699 // list[3] = ""
700 // list[4] = ""
701 list.sort(ClassLoaderExt::compare_module_names);
702
703 const char* prefix = "";
704 stringStream st;
705 const char* last_string = ""; // This also filters out all empty strings
706 for (int i = 0; i < list.length(); i++) {
707 const char* m = list.at(i);
708 if (strcmp(m, last_string) != 0) { // filter out duplicates
709 st.print("%s%s", prefix, m);
710 last_string = m;
711 prefix = ",";
712 }
713 }
714
715 return (st.size() > 0) ? st.as_string() : nullptr; // Example: "java.base,java.compiler"
716 }
717
718 void Modules::define_archived_modules(Handle h_platform_loader, Handle h_system_loader, TRAPS) {
719 assert(CDSConfig::is_using_full_module_graph(), "must be");
720
721 // We don't want the classes used by the archived full module graph to be redefined by JVMTI.
722 // Luckily, such classes are loaded in the JVMTI "early" phase, and CDS is disabled if a JVMTI
723 // agent wants to redefine classes in this phase.
724 JVMTI_ONLY(assert(JvmtiExport::is_early_phase(), "must be"));
725 assert(!(JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()),
726 "CDS should be disabled if early class hooks are enabled");
727
728 Handle java_base_module(THREAD, ClassLoaderDataShared::restore_archived_oops_for_null_class_loader_data());
729 // Patch any previously loaded class's module field with java.base's java.lang.Module.
730 ModuleEntryTable::patch_javabase_entries(THREAD, java_base_module);
731
732 if (h_platform_loader.is_null()) {
733 THROW_MSG(vmSymbols::java_lang_NullPointerException(), "Null platform loader object");
734 }
735
736 if (h_system_loader.is_null()) {
737 THROW_MSG(vmSymbols::java_lang_NullPointerException(), "Null system loader object");
738 }
739
740 ClassLoaderData* platform_loader_data = SystemDictionary::register_loader(h_platform_loader);
741 SystemDictionary::set_platform_loader(platform_loader_data);
742 ClassLoaderDataShared::restore_java_platform_loader_from_archive(platform_loader_data);
743
744 ClassLoaderData* system_loader_data = SystemDictionary::register_loader(h_system_loader);
745 SystemDictionary::set_system_loader(system_loader_data);
746 // system_loader_data here is always an instance of jdk.internal.loader.ClassLoader$AppClassLoader.
747 // However, if -Djava.system.class.loader=xxx is specified, java_platform_loader() would
748 // be an instance of a user-defined class, so make sure this never happens.
749 assert(Arguments::get_property("java.system.class.loader") == nullptr,
750 "archived full module should have been disabled if -Djava.system.class.loader is specified");
751 ClassLoaderDataShared::restore_java_system_loader_from_archive(system_loader_data);
752 }
753
754 void Modules::check_cds_restrictions(Handle module1, Handle module2, TRAPS) {
755 if (CDSConfig::is_dumping_full_module_graph() && Universe::is_module_initialized()) {
756 if (CDSConfig::is_dumping_dynamic_proxies() && (is_dynamic_proxy_module(module1) || is_dynamic_proxy_module(module2))) {
757 // The only the we allow is to add or modify the jdk.proxy?? modules that are used for dynamic proxies.
758 } else {
759 THROW_MSG(vmSymbols::java_lang_UnsupportedOperationException(),
760 "During -Xshare:dump, module system cannot be modified after it's initialized");
761 }
762 }
763 }
764
765 #endif // INCLUDE_CDS_JAVA_HEAP
766
767 bool Modules::is_dynamic_proxy_module(Handle module) {
768 if (!module.is_null()) {
769 ModuleEntry* module_entry = java_lang_Module::module_entry(module());
770 return is_dynamic_proxy_module(module_entry);
771 }
772 return false;
773 }
774
775 bool Modules::is_dynamic_proxy_module(ModuleEntry* module_entry) {
776 return (module_entry != nullptr && module_entry->is_named() && module_entry->name()->starts_with("jdk.proxy"));
777 }
778
779 void Modules::set_bootloader_unnamed_module(Handle module, TRAPS) {
780 ResourceMark rm(THREAD);
781
782 if (module.is_null()) {
783 THROW_MSG(vmSymbols::java_lang_NullPointerException(), "Null module object");
784 }
785 if (!java_lang_Module::is_instance(module())) {
786 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
787 "module is not an instance of type java.lang.Module");
788 }
789
790 // Ensure that this is an unnamed module
791 oop name = java_lang_Module::name(module());
792 if (name != nullptr) {
793 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
794 "boot loader's unnamed module's java.lang.Module has a name");
795 }
796
797 // Validate java_base's loader is the boot loader.
798 oop loader = java_lang_Module::loader(module());
799 if (loader != nullptr) {
800 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
801 "Class loader must be the boot class loader");
802 }
803
804 log_debug(module)("set_bootloader_unnamed_module(): recording unnamed module for boot loader");
805
806 // Set java.lang.Module for the boot loader's unnamed module
807 ClassLoaderData* boot_loader_data = ClassLoaderData::the_null_class_loader_data();
808 ModuleEntry* unnamed_module = boot_loader_data->unnamed_module();
809 assert(unnamed_module != nullptr, "boot loader's unnamed ModuleEntry not defined");
810 unnamed_module->set_module(boot_loader_data->add_handle(module));
811 // Store pointer to the ModuleEntry in the unnamed module's java.lang.Module object.
812 java_lang_Module::set_module_entry(module(), unnamed_module);
813 }
814
815 void Modules::add_module_exports(Handle from_module, jstring package_name, Handle to_module, TRAPS) {
816 check_cds_restrictions(from_module, to_module, CHECK);
817
818 if (package_name == nullptr) {
819 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
820 "package is null");
821 }
822 if (from_module.is_null()) {
823 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
824 "from_module is null");
825 }
826 ModuleEntry* from_module_entry = get_module_entry(from_module, CHECK);
827 if (from_module_entry == nullptr) {
828 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
829 "from_module cannot be found");
830 }
831
832 // All packages in unnamed and open modules are exported by default.
833 if (!from_module_entry->is_named() || from_module_entry->is_open()) return;
834
835 ModuleEntry* to_module_entry;
836 if (to_module.is_null()) {
837 to_module_entry = nullptr; // It's an unqualified export.
838 } else {
839 to_module_entry = get_module_entry(to_module, CHECK);
840 if (to_module_entry == nullptr) {
841 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
842 "to_module is invalid");
843 }
844 }
845
846 PackageEntry* package_entry = nullptr;
847 char buf[128];
848 int package_len;
849
850 ResourceMark rm(THREAD);
851 const char* pkg = as_internal_package(JNIHandles::resolve_non_null(package_name), buf, sizeof(buf), package_len);
852 {
853 MutexLocker ml(THREAD, Module_lock);
854 package_entry = get_locked_package_entry(from_module_entry, pkg, package_len);
855 // Do nothing if modules are the same
856 // If the package is not found we'll throw an exception later
857 if (from_module_entry != to_module_entry &&
858 package_entry != nullptr) {
859 package_entry->set_exported(to_module_entry);
860 }
861 }
862
863 // Handle errors and logging outside locked section
864 if (package_entry == nullptr) {
865 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
866 err_msg("Package %s not found in from_module %s",
867 pkg != nullptr ? pkg : "",
868 from_module_entry->name()->as_C_string()));
869 }
870
871 if (log_is_enabled(Debug, module)) {
872 log_debug(module)("add_module_exports(): package %s in module %s is exported to module %s",
873 package_entry->name()->as_C_string(),
874 from_module_entry->name()->as_C_string(),
875 to_module_entry == nullptr ? "null" :
876 to_module_entry->is_named() ?
877 to_module_entry->name()->as_C_string() : UNNAMED_MODULE);
878 }
879 }
880
881
882 void Modules::add_module_exports_qualified(Handle from_module, jstring package,
883 Handle to_module, TRAPS) {
884 check_cds_restrictions(from_module, to_module, CHECK);
885 if (to_module.is_null()) {
886 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
887 "to_module is null");
888 }
889 add_module_exports(from_module, package, to_module, CHECK);
890 }
891
892 void Modules::add_reads_module(Handle from_module, Handle to_module, TRAPS) {
893 check_cds_restrictions(from_module, to_module, CHECK);
894 if (from_module.is_null()) {
895 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
896 "from_module is null");
897 }
898
899 ModuleEntry* from_module_entry = get_module_entry(from_module, CHECK);
900 if (from_module_entry == nullptr) {
901 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
902 "from_module is not valid");
903 }
904
905 ModuleEntry* to_module_entry;
906 if (!to_module.is_null()) {
907 to_module_entry = get_module_entry(to_module, CHECK);
908 if (to_module_entry == nullptr) {
909 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
910 "to_module is invalid");
911 }
912 } else {
913 to_module_entry = nullptr;
914 }
915
916 ResourceMark rm(THREAD);
917 log_debug(module)("add_reads_module(): Adding read from module %s to module %s",
918 from_module_entry->is_named() ?
919 from_module_entry->name()->as_C_string() : UNNAMED_MODULE,
920 to_module_entry == nullptr ? "all unnamed" :
921 (to_module_entry->is_named() ?
922 to_module_entry->name()->as_C_string() : UNNAMED_MODULE));
923
924 // if modules are the same or if from_module is unnamed then no need to add the read.
925 if (from_module_entry != to_module_entry && from_module_entry->is_named()) {
926 from_module_entry->add_read(to_module_entry);
927 }
928 }
929
930 // This method is called by JFR and JNI.
931 jobject Modules::get_module(jclass clazz, TRAPS) {
932 assert(ModuleEntryTable::javabase_defined(),
933 "Attempt to call get_module before " JAVA_BASE_NAME " is defined");
934
935 if (clazz == nullptr) {
936 THROW_MSG_(vmSymbols::java_lang_NullPointerException(),
937 "class is null", nullptr);
938 }
939 oop mirror = JNIHandles::resolve_non_null(clazz);
940 if (mirror == nullptr) {
941 log_debug(module)("get_module(): no mirror, returning nullptr");
942 return nullptr;
943 }
944 if (!java_lang_Class::is_instance(mirror)) {
945 THROW_MSG_(vmSymbols::java_lang_IllegalArgumentException(),
946 "Invalid class", nullptr);
947 }
948
949 oop module = java_lang_Class::module(mirror);
950
951 assert(module != nullptr, "java.lang.Class module field not set");
952 assert(java_lang_Module::is_instance(module), "module is not an instance of type java.lang.Module");
953
954 LogTarget(Debug,module) lt;
955 if (lt.is_enabled()) {
956 ResourceMark rm(THREAD);
957 LogStream ls(lt);
958 Klass* klass = java_lang_Class::as_Klass(mirror);
959 oop module_name = java_lang_Module::name(module);
960 if (module_name != nullptr) {
961 ls.print("get_module(): module ");
962 java_lang_String::print(module_name, tty);
963 } else {
964 ls.print("get_module(): Unnamed Module");
965 }
966 if (klass != nullptr) {
967 ls.print_cr(" for class %s", klass->external_name());
968 } else {
969 ls.print_cr(" for primitive class");
970 }
971 }
972
973 return JNIHandles::make_local(THREAD, module);
974 }
975
976 oop Modules::get_named_module(Handle h_loader, const char* package_name) {
977 assert(ModuleEntryTable::javabase_defined(),
978 "Attempt to call get_named_module before " JAVA_BASE_NAME " is defined");
979 assert(h_loader.is_null() || java_lang_ClassLoader::is_subclass(h_loader->klass()),
980 "Class loader is not a subclass of java.lang.ClassLoader");
981 assert(package_name != nullptr, "the package_name should not be null");
982
983 if (strlen(package_name) == 0) {
984 return nullptr;
985 }
986 TempNewSymbol package_sym = SymbolTable::new_symbol(package_name);
987 const PackageEntry* const pkg_entry =
988 get_package_entry_by_name(package_sym, h_loader);
989 const ModuleEntry* const module_entry = (pkg_entry != nullptr ? pkg_entry->module() : nullptr);
990
991 if (module_entry != nullptr && module_entry->module() != nullptr && module_entry->is_named()) {
992 return module_entry->module();
993 }
994 return nullptr;
995 }
996
997 // Export package in module to all unnamed modules.
998 void Modules::add_module_exports_to_all_unnamed(Handle module, jstring package_name, TRAPS) {
999 check_cds_restrictions(Handle(), module, CHECK);
1000 if (module.is_null()) {
1001 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
1002 "module is null");
1003 }
1004 if (package_name == nullptr) {
1005 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
1006 "package is null");
1007 }
1008 ModuleEntry* module_entry = get_module_entry(module, CHECK);
1009 if (module_entry == nullptr) {
1010 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
1011 "module is invalid");
1012 }
1013
1014 // No-op for unnamed module and open modules
1015 if (!module_entry->is_named() || module_entry->is_open())
1016 return;
1017
1018 ResourceMark rm(THREAD);
1019 char buf[128];
1020 int pkg_len;
1021 const char* pkg = as_internal_package(JNIHandles::resolve_non_null(package_name), buf, sizeof(buf), pkg_len);
1022 PackageEntry* package_entry = nullptr;
1023 {
1024 MutexLocker m1(THREAD, Module_lock);
1025 package_entry = get_locked_package_entry(module_entry, pkg, pkg_len);
1026
1027 // Mark package as exported to all unnamed modules.
1028 if (package_entry != nullptr) {
1029 package_entry->set_is_exported_allUnnamed();
1030 }
1031 }
1032
1033 // Handle errors and logging outside locked section
1034 if (package_entry == nullptr) {
1035 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
1036 err_msg("Package %s not found in module %s",
1037 pkg != nullptr ? pkg : "",
1038 module_entry->name()->as_C_string()));
1039 }
1040
1041 if (log_is_enabled(Debug, module)) {
1042 log_debug(module)("add_module_exports_to_all_unnamed(): package %s in module"
1043 " %s is exported to all unnamed modules",
1044 package_entry->name()->as_C_string(),
1045 module_entry->name()->as_C_string());
1046 }
1047 }