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 check_cds_restrictions(CHECK);
282 ResourceMark rm(THREAD);
283
284 if (module.is_null()) {
285 THROW_MSG(vmSymbols::java_lang_NullPointerException(), "Null module object");
286 }
287
288 if (!java_lang_Module::is_instance(module())) {
289 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
290 "module is not an instance of type java.lang.Module");
291 }
292
293 int module_name_len;
294 char* module_name = get_module_name(module(), module_name_len, CHECK);
295 if (module_name == nullptr) {
296 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
297 "Module name cannot be null");
298 }
299
300 // Resolve packages
301 objArrayHandle packages_h(THREAD, objArrayOop(JNIHandles::resolve(packages)));
302 int num_packages = (packages_h.is_null() ? 0 : packages_h->length());
303
304 // Special handling of java.base definition
305 if (strcmp(module_name, JAVA_BASE_NAME) == 0) {
306 assert(is_open == JNI_FALSE, "java.base module cannot be open");
307 define_javabase_module(module, version, location, packages_h, num_packages, CHECK);
308 return;
309 }
310
311 oop loader = java_lang_Module::loader(module());
312 Handle h_loader = Handle(THREAD, loader);
313 // define_module can be called during start-up, before the class loader's ClassLoaderData
314 // has been created. SystemDictionary::register_loader ensures creation, if needed.
315 ClassLoaderData* loader_data = SystemDictionary::register_loader(h_loader);
316 assert(loader_data != nullptr, "class loader data shouldn't be null");
317
318 // Only modules defined to either the boot or platform class loader, can define a "java/" package.
319 bool java_pkg_disallowed = !h_loader.is_null() &&
320 !SystemDictionary::is_platform_class_loader(h_loader());
321
322 // Check that the list of packages has no duplicates and that the
323 // packages are syntactically ok.
324 char buf[128];
325 GrowableArray<Symbol*>* pkg_list = new GrowableArray<Symbol*>(num_packages);
326 for (int x = 0; x < num_packages; x++) {
327 oop pkg_str = packages_h->obj_at(x);
328 if (pkg_str == nullptr || pkg_str->klass() != vmClasses::String_klass()) {
329 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
330 err_msg("Bad package name"));
331 }
332
333 int package_len;
334 const char* package_name = as_internal_package(pkg_str, buf, sizeof(buf), package_len);
335 if (!verify_package_name(package_name, package_len)) {
336 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
337 err_msg("Invalid package name: %s for module: %s",
338 package_name, module_name));
339 }
340
341 // Only modules defined to either the boot or platform class loader, can define a "java/" package.
342 if (java_pkg_disallowed &&
343 (strncmp(package_name, JAVAPKG, JAVAPKG_LEN) == 0 &&
344 (package_name[JAVAPKG_LEN] == JVM_SIGNATURE_SLASH || package_name[JAVAPKG_LEN] == '\0'))) {
345 const char* class_loader_name = loader_data->loader_name_and_id();
346 size_t pkg_len = strlen(package_name);
347 char* pkg_name = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, pkg_len + 1);
348 strncpy(pkg_name, package_name, pkg_len + 1);
349 StringUtils::replace_no_expand(pkg_name, "/", ".");
350 const char* msg_text1 = "Class loader (instance of): ";
351 const char* msg_text2 = " tried to define prohibited package name: ";
352 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + pkg_len + 1;
353 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
354 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, pkg_name);
355 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), message);
356 }
357
358 Symbol* pkg_symbol = SymbolTable::new_symbol(package_name, package_len);
359 pkg_list->append(pkg_symbol);
360 }
361
362 ModuleEntryTable* module_table = get_module_entry_table(h_loader);
363 assert(module_table != nullptr, "module entry table shouldn't be null");
364
365 // Create symbol* entry for module name.
366 TempNewSymbol module_symbol = SymbolTable::new_symbol(module_name, module_name_len);
367
368 bool dupl_modules = false;
369
370 // Create symbol for module version.
371 TempNewSymbol version_symbol = as_symbol(version);
372
373 // Create symbol* entry for module location.
374 TempNewSymbol location_symbol = as_symbol(location);
375
376 PackageEntryTable* package_table = nullptr;
377 PackageEntry* existing_pkg = nullptr;
378 {
379 MutexLocker ml(THREAD, Module_lock);
380
381 if (num_packages > 0) {
382 package_table = get_package_entry_table(h_loader);
383 assert(package_table != nullptr, "Missing package_table");
384
385 // Check that none of the packages exist in the class loader's package table.
386 for (int x = 0; x < pkg_list->length(); x++) {
387 existing_pkg = package_table->locked_lookup_only(pkg_list->at(x));
388 if (existing_pkg != nullptr) {
389 // This could be because the module was already defined. If so,
390 // report that error instead of the package error.
391 if (module_table->lookup_only(module_symbol) != nullptr) {
392 dupl_modules = true;
393 }
394 break;
395 }
396 }
397 } // if (num_packages > 0)...
398
399 // Add the module and its packages.
400 if (!dupl_modules && existing_pkg == nullptr) {
401 if (module_table->lookup_only(module_symbol) == nullptr) {
402 // Create the entry for this module in the class loader's module entry table.
403 ModuleEntry* module_entry = module_table->locked_create_entry(module,
404 (is_open == JNI_TRUE), module_symbol,
405 version_symbol, location_symbol, loader_data);
406 assert(module_entry != nullptr, "module_entry creation failed");
407
408 // Add the packages.
409 assert(pkg_list->length() == 0 || package_table != nullptr, "Bad package table");
410 for (int y = 0; y < pkg_list->length(); y++) {
411 package_table->locked_create_entry(pkg_list->at(y), module_entry);
412
413 // Unable to have a GrowableArray of TempNewSymbol. Must decrement the refcount of
414 // the Symbol* that was created above for each package. The refcount was incremented
415 // by SymbolTable::new_symbol and as well by the PackageEntry creation.
416 pkg_list->at(y)->decrement_refcount();
417 }
418
419 // Store pointer to ModuleEntry record in java.lang.Module object.
420 java_lang_Module::set_module_entry(module(), module_entry);
421 } else {
422 dupl_modules = true;
423 }
424 }
425 } // Release the lock
426
427 // any errors ?
428 if (dupl_modules) {
429 THROW_MSG(vmSymbols::java_lang_IllegalStateException(),
430 err_msg("Module %s is already defined", module_name));
431 } else if (existing_pkg != nullptr) {
432 throw_dup_pkg_exception(module_name, existing_pkg, CHECK);
433 }
434
435 log_info(module, load)("%s location: %s", module_name,
436 location_symbol != nullptr ? location_symbol->as_C_string() : "null");
437 LogTarget(Debug, module) lt;
438 if (lt.is_enabled()) {
439 LogStream ls(lt);
440 ls.print("define_module(): creation of module: %s, version: %s, location: %s, ",
441 module_name, version_symbol != nullptr ? version_symbol->as_C_string() : "null",
442 location_symbol != nullptr ? location_symbol->as_C_string() : "null");
443 loader_data->print_value_on(&ls);
444 ls.print_cr(", package #: %d", pkg_list->length());
445 for (int y = 0; y < pkg_list->length(); y++) {
446 log_trace(module)("define_module(): creation of package %s for module %s",
447 (pkg_list->at(y))->as_C_string(), module_name);
448 }
449 }
450
451 // If the module is defined to the boot loader and an exploded build is being
452 // used, prepend <java.home>/modules/modules_name to the boot class path.
453 if (h_loader.is_null() && !ClassLoader::has_jrt_entry()) {
454 ClassLoader::add_to_exploded_build_list(THREAD, module_symbol);
455 }
456
457 #if COMPILER2_OR_JVMCI
458 // Special handling of jdk.incubator.vector
459 if (strcmp(module_name, "jdk.incubator.vector") == 0) {
460 if (FLAG_IS_DEFAULT(EnableVectorSupport)) {
461 FLAG_SET_DEFAULT(EnableVectorSupport, true);
462 }
463 if (EnableVectorSupport && FLAG_IS_DEFAULT(EnableVectorReboxing)) {
464 FLAG_SET_DEFAULT(EnableVectorReboxing, true);
465 }
466 if (EnableVectorSupport && EnableVectorReboxing && FLAG_IS_DEFAULT(EnableVectorAggressiveReboxing)) {
467 FLAG_SET_DEFAULT(EnableVectorAggressiveReboxing, true);
468 }
469 log_info(compilation)("EnableVectorSupport=%s", (EnableVectorSupport ? "true" : "false"));
470 log_info(compilation)("EnableVectorReboxing=%s", (EnableVectorReboxing ? "true" : "false"));
471 log_info(compilation)("EnableVectorAggressiveReboxing=%s", (EnableVectorAggressiveReboxing ? "true" : "false"));
472 }
473 #endif // COMPILER2_OR_JVMCI
474 }
475
476 #if INCLUDE_CDS_JAVA_HEAP
477 static bool _seen_platform_unnamed_module = false;
478 static bool _seen_system_unnamed_module = false;
479
480 // Validate the states of an java.lang.Module oop to be archived.
481 void Modules::check_archived_module_oop(oop orig_module_obj) {
482 assert(CDSConfig::is_dumping_full_module_graph(), "must be");
483 assert(java_lang_Module::is_instance(orig_module_obj), "must be");
484
485 ModuleEntry* orig_module_ent = java_lang_Module::module_entry_raw(orig_module_obj);
486 if (orig_module_ent == nullptr) {
487 // These special java.lang.Module oops are created in Java code. They are not
488 // defined via Modules::define_module(), so they don't have a ModuleEntry:
489 // java.lang.Module::ALL_UNNAMED_MODULE
490 // java.lang.Module::EVERYONE_MODULE
491 // jdk.internal.loader.ClassLoaders$BootClassLoader::unnamedModule
492 log_info(cds, module)("Archived java.lang.Module oop " PTR_FORMAT " with no ModuleEntry*", p2i(orig_module_obj));
493 assert(java_lang_Module::name(orig_module_obj) == nullptr, "must be unnamed");
494 } else {
495 // This java.lang.Module oop has an ModuleEntry*. Check if the latter is archived.
496 if (log_is_enabled(Info, cds, module)) {
497 ResourceMark rm;
498 LogStream ls(Log(cds, module)::info());
499 ls.print("Archived java.lang.Module oop " PTR_FORMAT " for ", p2i(orig_module_obj));
500 orig_module_ent->print(&ls);
501 }
502
503 // We only archive the default module graph, which should contain only java.lang.Module oops
504 // for the 3 built-in loaders (boot/platform/system)
505 ClassLoaderData* loader_data = orig_module_ent->loader_data();
506 assert(loader_data->is_builtin_class_loader_data(), "must be");
507
508 if (orig_module_ent->name() != nullptr) {
509 // For each named module, we archive both the java.lang.Module oop and the ModuleEntry.
510 assert(orig_module_ent->has_been_archived(), "sanity");
511 } else {
512 // We only archive two unnamed module oops (for platform and system loaders). These do NOT have an archived
513 // ModuleEntry.
514 //
515 // At runtime, these oops are fetched from java_lang_ClassLoader::unnamedModule(loader) and
516 // are initialized in ClassLoaderData::ClassLoaderData() => ModuleEntry::create_unnamed_module(), where
517 // a new ModuleEntry is allocated.
518 assert(!loader_data->is_boot_class_loader_data(), "unnamed module for boot loader should be not archived");
519 assert(!orig_module_ent->has_been_archived(), "sanity");
520
521 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 // The java.lang.Module oop and ModuleEntry of the unnamed module of the boot loader are
529 // not in the archived module graph. These are always allocated at runtime.
530 ShouldNotReachHere();
531 }
532 }
533 }
534 }
535
536 void Modules::verify_archived_modules() {
537 ModuleEntry::verify_archived_module_entries();
538 }
539
540 class Modules::ArchivedProperty {
541 const char* _prop;
542 const bool _numbered;
543 const char* _archived_value;
544
545 const char* get_flattened_value() const {
546 if (_numbered) {
547 return get_numbered_property_as_sorted_string();
548 } else {
549 return Arguments::get_property(_prop);
550 }
551 }
552
553 void runtime_check() const;
554 const char* get_numbered_property_as_sorted_string() const;
555
556 public:
557 ArchivedProperty(const char* prop, bool numbered)
558 : _prop(prop), _numbered(numbered), _archived_value(nullptr) {}
559
560 void dump() {
561 ResourceMark rm;
562 const char* str = get_flattened_value();
563 if (str != nullptr) {
564 _archived_value = ArchiveBuilder::current()->ro_strdup(str);
565 }
566 }
567
568 void serialize(SerializeClosure* soc) {
569 soc->do_ptr(&_archived_value);
570 if (soc->reading()) {
571 runtime_check();
572 // Don't hold onto the pointer, in case we might decide to unmap the archive.
573 _archived_value = nullptr;
574 }
575 }
576 };
577
578 Modules::ArchivedProperty Modules::_archived_props[] = {
579 // non-numbered
580 {"jdk.module.main", false},
581
582 // numbered
583 {"jdk.module.addexports", true}, // --add-exports
584 {"jdk.module.addmods", true}, // --add-modules
585 {"jdk.module.enable.native.access", true}, // --enable-native-access
586 {"jdk.module.addopens", true}, // --add-opens
587 };
588
589 constexpr size_t Modules::num_archived_props() {
590 return sizeof(_archived_props) / sizeof(_archived_props[0]);
591 }
592
593 Modules::ArchivedProperty& Modules::archived_prop(size_t i) {
594 assert(i < num_archived_props(), "oob");
595 return _archived_props[i];
596 }
597
598 void Modules::ArchivedProperty::runtime_check() const {
599 ResourceMark rm;
600 const char* runtime_value = get_flattened_value();
601 log_info(cds)("archived module property %s: %s", _prop,
602 _archived_value != nullptr ? _archived_value : "(null)");
603
604 bool disable = false;
605 if (runtime_value == nullptr) {
606 if (_archived_value != nullptr) {
607 log_info(cds)("Mismatched values for property %s: %s specified during dump time but not during runtime", _prop, _archived_value);
608 disable = true;
609 }
610 } else {
611 if (_archived_value == nullptr) {
612 log_info(cds)("Mismatched values for property %s: %s specified during runtime but not during dump time", _prop, runtime_value);
613 disable = true;
614 } else if (strcmp(runtime_value, _archived_value) != 0) {
615 log_info(cds)("Mismatched values for property %s: runtime %s dump time %s", _prop, runtime_value, _archived_value);
616 disable = true;
617 }
618 }
619
620 if (disable) {
621 log_info(cds)("Disabling optimized module handling");
622 CDSConfig::stop_using_optimized_module_handling();
623 }
624 }
625
626 // Caller needs ResourceMark
627 const char* Modules::ArchivedProperty::get_numbered_property_as_sorted_string() const {
628 assert(_numbered, "sanity");
629 // theoretical string size limit for decimal int, but the following loop will end much sooner due to
630 // OS command-line size limit.
631 const int max_digits = 10;
632 const int extra_symbols_count = 2; // includes '.', '\0'
633 size_t prop_len = strlen(_prop) + max_digits + extra_symbols_count;
634 char* prop_name = resource_allocate_bytes(prop_len);
635 GrowableArray<const char*> list;
636 for (unsigned int i = 0;; i++) {
637 jio_snprintf(prop_name, prop_len, "%s.%d", _prop, i);
638 const char* prop_value = Arguments::get_property(prop_name);
639 if (prop_value == nullptr) {
640 break;
641 }
642 char* p = resource_allocate_bytes(strlen(prop_value) + 1);
643 strcpy(p, prop_value);
644 while (*p == ',') p++; // skip leading commas
645 while (*p) {
646 char* next = strchr(p, ',');
647 if (next == nullptr) {
648 // no more commas, p is the last element
649 list.append(p);
650 break;
651 } else {
652 *next = 0;
653 list.append(p);
654 p = next + 1;
655 }
656 }
657 }
658
659 // Example:
660 // --add-modules=java.compiler --add-modules=java.base,java.base,,
661 //
662 // list[0] = "java.compiler"
663 // list[1] = "java.base"
664 // list[2] = "java.base"
665 // list[3] = ""
666 // list[4] = ""
667 list.sort(ClassLoaderExt::compare_module_names);
668
669 const char* prefix = "";
670 stringStream st;
671 const char* last_string = ""; // This also filters out all empty strings
672 for (int i = 0; i < list.length(); i++) {
673 const char* m = list.at(i);
674 if (strcmp(m, last_string) != 0) { // filter out duplicates
675 st.print("%s%s", prefix, m);
676 last_string = m;
677 prefix = ",";
678 }
679 }
680
681 return (st.size() > 0) ? st.as_string() : nullptr; // Example: "java.base,java.compiler"
682 }
683
684 void Modules::dump_archived_module_info() {
685 for (size_t i = 0; i < num_archived_props(); i++) {
686 archived_prop(i).dump();
687 }
688 }
689
690 void Modules::serialize_archived_module_info(SerializeClosure* soc) {
691 for (size_t i = 0; i < num_archived_props(); i++) {
692 archived_prop(i).serialize(soc);
693 }
694 if (soc->reading()) {
695 log_info(cds)("optimized module handling: %s", CDSConfig::is_using_optimized_module_handling() ? "enabled" : "disabled");
696 log_info(cds)("full module graph: %s", CDSConfig::is_using_full_module_graph() ? "enabled" : "disabled");
697 }
698 }
699
700 void Modules::define_archived_modules(Handle h_platform_loader, Handle h_system_loader, TRAPS) {
701 assert(CDSConfig::is_using_full_module_graph(), "must be");
702
703 // We don't want the classes used by the archived full module graph to be redefined by JVMTI.
704 // Luckily, such classes are loaded in the JVMTI "early" phase, and CDS is disabled if a JVMTI
705 // agent wants to redefine classes in this phase.
706 JVMTI_ONLY(assert(JvmtiExport::is_early_phase(), "must be"));
707 assert(!(JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()),
708 "CDS should be disabled if early class hooks are enabled");
709
710 Handle java_base_module(THREAD, ClassLoaderDataShared::restore_archived_oops_for_null_class_loader_data());
711 // Patch any previously loaded class's module field with java.base's java.lang.Module.
712 ModuleEntryTable::patch_javabase_entries(THREAD, java_base_module);
713
714 if (h_platform_loader.is_null()) {
715 THROW_MSG(vmSymbols::java_lang_NullPointerException(), "Null platform loader object");
716 }
717
718 if (h_system_loader.is_null()) {
719 THROW_MSG(vmSymbols::java_lang_NullPointerException(), "Null system loader object");
720 }
721
722 ClassLoaderData* platform_loader_data = SystemDictionary::register_loader(h_platform_loader);
723 SystemDictionary::set_platform_loader(platform_loader_data);
724 ClassLoaderDataShared::restore_java_platform_loader_from_archive(platform_loader_data);
725
726 ClassLoaderData* system_loader_data = SystemDictionary::register_loader(h_system_loader);
727 SystemDictionary::set_system_loader(system_loader_data);
728 // system_loader_data here is always an instance of jdk.internal.loader.ClassLoader$AppClassLoader.
729 // However, if -Djava.system.class.loader=xxx is specified, java_platform_loader() would
730 // be an instance of a user-defined class, so make sure this never happens.
731 assert(Arguments::get_property("java.system.class.loader") == nullptr,
732 "archived full module should have been disabled if -Djava.system.class.loader is specified");
733 ClassLoaderDataShared::restore_java_system_loader_from_archive(system_loader_data);
734 }
735
736 void Modules::check_cds_restrictions(TRAPS) {
737 if (CDSConfig::is_dumping_full_module_graph() && Universe::is_module_initialized()) {
738 THROW_MSG(vmSymbols::java_lang_UnsupportedOperationException(),
739 "During -Xshare:dump, module system cannot be modified after it's initialized");
740 }
741 }
742 #endif // INCLUDE_CDS_JAVA_HEAP
743
744 void Modules::set_bootloader_unnamed_module(Handle module, TRAPS) {
745 ResourceMark rm(THREAD);
746
747 if (module.is_null()) {
748 THROW_MSG(vmSymbols::java_lang_NullPointerException(), "Null module object");
749 }
750 if (!java_lang_Module::is_instance(module())) {
751 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
752 "module is not an instance of type java.lang.Module");
753 }
754
755 // Ensure that this is an unnamed module
756 oop name = java_lang_Module::name(module());
757 if (name != nullptr) {
758 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
759 "boot loader's unnamed module's java.lang.Module has a name");
760 }
761
762 // Validate java_base's loader is the boot loader.
763 oop loader = java_lang_Module::loader(module());
764 if (loader != nullptr) {
765 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
766 "Class loader must be the boot class loader");
767 }
768
769 log_debug(module)("set_bootloader_unnamed_module(): recording unnamed module for boot loader");
770
771 // Set java.lang.Module for the boot loader's unnamed module
772 ClassLoaderData* boot_loader_data = ClassLoaderData::the_null_class_loader_data();
773 ModuleEntry* unnamed_module = boot_loader_data->unnamed_module();
774 assert(unnamed_module != nullptr, "boot loader's unnamed ModuleEntry not defined");
775 unnamed_module->set_module(boot_loader_data->add_handle(module));
776 // Store pointer to the ModuleEntry in the unnamed module's java.lang.Module object.
777 java_lang_Module::set_module_entry(module(), unnamed_module);
778 }
779
780 void Modules::add_module_exports(Handle from_module, jstring package_name, Handle to_module, TRAPS) {
781 check_cds_restrictions(CHECK);
782
783 if (package_name == nullptr) {
784 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
785 "package is null");
786 }
787 if (from_module.is_null()) {
788 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
789 "from_module is null");
790 }
791 ModuleEntry* from_module_entry = get_module_entry(from_module, CHECK);
792 if (from_module_entry == nullptr) {
793 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
794 "from_module cannot be found");
795 }
796
797 // All packages in unnamed and open modules are exported by default.
798 if (!from_module_entry->is_named() || from_module_entry->is_open()) return;
799
800 ModuleEntry* to_module_entry;
801 if (to_module.is_null()) {
802 to_module_entry = nullptr; // It's an unqualified export.
803 } else {
804 to_module_entry = get_module_entry(to_module, CHECK);
805 if (to_module_entry == nullptr) {
806 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
807 "to_module is invalid");
808 }
809 }
810
811 PackageEntry* package_entry = nullptr;
812 char buf[128];
813 int package_len;
814
815 ResourceMark rm(THREAD);
816 const char* pkg = as_internal_package(JNIHandles::resolve_non_null(package_name), buf, sizeof(buf), package_len);
817 {
818 MutexLocker ml(THREAD, Module_lock);
819 package_entry = get_locked_package_entry(from_module_entry, pkg, package_len);
820 // Do nothing if modules are the same
821 // If the package is not found we'll throw an exception later
822 if (from_module_entry != to_module_entry &&
823 package_entry != nullptr) {
824 package_entry->set_exported(to_module_entry);
825 }
826 }
827
828 // Handle errors and logging outside locked section
829 if (package_entry == nullptr) {
830 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
831 err_msg("Package %s not found in from_module %s",
832 pkg != nullptr ? pkg : "",
833 from_module_entry->name()->as_C_string()));
834 }
835
836 if (log_is_enabled(Debug, module)) {
837 log_debug(module)("add_module_exports(): package %s in module %s is exported to module %s",
838 package_entry->name()->as_C_string(),
839 from_module_entry->name()->as_C_string(),
840 to_module_entry == nullptr ? "null" :
841 to_module_entry->is_named() ?
842 to_module_entry->name()->as_C_string() : UNNAMED_MODULE);
843 }
844 }
845
846
847 void Modules::add_module_exports_qualified(Handle from_module, jstring package,
848 Handle to_module, TRAPS) {
849 check_cds_restrictions(CHECK);
850 if (to_module.is_null()) {
851 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
852 "to_module is null");
853 }
854 add_module_exports(from_module, package, to_module, CHECK);
855 }
856
857 void Modules::add_reads_module(Handle from_module, Handle to_module, TRAPS) {
858 check_cds_restrictions(CHECK);
859 if (from_module.is_null()) {
860 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
861 "from_module is null");
862 }
863
864 ModuleEntry* from_module_entry = get_module_entry(from_module, CHECK);
865 if (from_module_entry == nullptr) {
866 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
867 "from_module is not valid");
868 }
869
870 ModuleEntry* to_module_entry;
871 if (!to_module.is_null()) {
872 to_module_entry = get_module_entry(to_module, CHECK);
873 if (to_module_entry == nullptr) {
874 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
875 "to_module is invalid");
876 }
877 } else {
878 to_module_entry = nullptr;
879 }
880
881 ResourceMark rm(THREAD);
882 log_debug(module)("add_reads_module(): Adding read from module %s to module %s",
883 from_module_entry->is_named() ?
884 from_module_entry->name()->as_C_string() : UNNAMED_MODULE,
885 to_module_entry == nullptr ? "all unnamed" :
886 (to_module_entry->is_named() ?
887 to_module_entry->name()->as_C_string() : UNNAMED_MODULE));
888
889 // if modules are the same or if from_module is unnamed then no need to add the read.
890 if (from_module_entry != to_module_entry && from_module_entry->is_named()) {
891 from_module_entry->add_read(to_module_entry);
892 }
893 }
894
895 // This method is called by JFR and JNI.
896 jobject Modules::get_module(jclass clazz, TRAPS) {
897 assert(ModuleEntryTable::javabase_defined(),
898 "Attempt to call get_module before " JAVA_BASE_NAME " is defined");
899
900 if (clazz == nullptr) {
901 THROW_MSG_(vmSymbols::java_lang_NullPointerException(),
902 "class is null", nullptr);
903 }
904 oop mirror = JNIHandles::resolve_non_null(clazz);
905 if (mirror == nullptr) {
906 log_debug(module)("get_module(): no mirror, returning nullptr");
907 return nullptr;
908 }
909 if (!java_lang_Class::is_instance(mirror)) {
910 THROW_MSG_(vmSymbols::java_lang_IllegalArgumentException(),
911 "Invalid class", nullptr);
912 }
913
914 oop module = java_lang_Class::module(mirror);
915
916 assert(module != nullptr, "java.lang.Class module field not set");
917 assert(java_lang_Module::is_instance(module), "module is not an instance of type java.lang.Module");
918
919 LogTarget(Debug,module) lt;
920 if (lt.is_enabled()) {
921 LogStream ls(lt);
922 Klass* klass = java_lang_Class::as_Klass(mirror);
923 oop module_name = java_lang_Module::name(module);
924 if (module_name != nullptr) {
925 ls.print("get_module(): module ");
926 java_lang_String::print(module_name, tty);
927 } else {
928 ls.print("get_module(): Unnamed Module");
929 }
930 if (klass != nullptr) {
931 ResourceMark rm(THREAD);
932 ls.print_cr(" for class %s", klass->external_name());
933 } else {
934 ls.print_cr(" for primitive class");
935 }
936 }
937
938 return JNIHandles::make_local(THREAD, module);
939 }
940
941 oop Modules::get_named_module(Handle h_loader, const char* package_name) {
942 assert(ModuleEntryTable::javabase_defined(),
943 "Attempt to call get_named_module before " JAVA_BASE_NAME " is defined");
944 assert(h_loader.is_null() || java_lang_ClassLoader::is_subclass(h_loader->klass()),
945 "Class loader is not a subclass of java.lang.ClassLoader");
946 assert(package_name != nullptr, "the package_name should not be null");
947
948 if (strlen(package_name) == 0) {
949 return nullptr;
950 }
951 TempNewSymbol package_sym = SymbolTable::new_symbol(package_name);
952 const PackageEntry* const pkg_entry =
953 get_package_entry_by_name(package_sym, h_loader);
954 const ModuleEntry* const module_entry = (pkg_entry != nullptr ? pkg_entry->module() : nullptr);
955
956 if (module_entry != nullptr && module_entry->module() != nullptr && module_entry->is_named()) {
957 return module_entry->module();
958 }
959 return nullptr;
960 }
961
962 // Export package in module to all unnamed modules.
963 void Modules::add_module_exports_to_all_unnamed(Handle module, jstring package_name, TRAPS) {
964 check_cds_restrictions(CHECK);
965 if (module.is_null()) {
966 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
967 "module is null");
968 }
969 if (package_name == nullptr) {
970 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
971 "package is null");
972 }
973 ModuleEntry* module_entry = get_module_entry(module, CHECK);
974 if (module_entry == nullptr) {
975 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
976 "module is invalid");
977 }
978
979 // No-op for unnamed module and open modules
980 if (!module_entry->is_named() || module_entry->is_open())
981 return;
982
983 ResourceMark rm(THREAD);
984 char buf[128];
985 int pkg_len;
986 const char* pkg = as_internal_package(JNIHandles::resolve_non_null(package_name), buf, sizeof(buf), pkg_len);
987 PackageEntry* package_entry = nullptr;
988 {
989 MutexLocker m1(THREAD, Module_lock);
990 package_entry = get_locked_package_entry(module_entry, pkg, pkg_len);
991
992 // Mark package as exported to all unnamed modules.
993 if (package_entry != nullptr) {
994 package_entry->set_is_exported_allUnnamed();
995 }
996 }
997
998 // Handle errors and logging outside locked section
999 if (package_entry == nullptr) {
1000 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
1001 err_msg("Package %s not found in module %s",
1002 pkg != nullptr ? pkg : "",
1003 module_entry->name()->as_C_string()));
1004 }
1005
1006 if (log_is_enabled(Debug, module)) {
1007 log_debug(module)("add_module_exports_to_all_unnamed(): package %s in module"
1008 " %s is exported to all unnamed modules",
1009 package_entry->name()->as_C_string(),
1010 module_entry->name()->as_C_string());
1011 }
1012 }