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 if (EnableVectorSupport && FLAG_IS_DEFAULT(UseVectorStubs)) {
470 FLAG_SET_DEFAULT(UseVectorStubs, true);
471 }
472 log_info(compilation)("EnableVectorSupport=%s", (EnableVectorSupport ? "true" : "false"));
473 log_info(compilation)("EnableVectorReboxing=%s", (EnableVectorReboxing ? "true" : "false"));
474 log_info(compilation)("EnableVectorAggressiveReboxing=%s", (EnableVectorAggressiveReboxing ? "true" : "false"));
475 log_info(compilation)("UseVectorStubs=%s", (UseVectorStubs ? "true" : "false"));
476 }
477 #endif // COMPILER2_OR_JVMCI
478 }
479
480 #if INCLUDE_CDS_JAVA_HEAP
481 static bool _seen_platform_unnamed_module = false;
482 static bool _seen_system_unnamed_module = false;
483
484 // Validate the states of an java.lang.Module oop to be archived.
485 void Modules::check_archived_module_oop(oop orig_module_obj) {
486 assert(CDSConfig::is_dumping_full_module_graph(), "must be");
487 assert(java_lang_Module::is_instance(orig_module_obj), "must be");
488
489 ModuleEntry* orig_module_ent = java_lang_Module::module_entry_raw(orig_module_obj);
490 if (orig_module_ent == nullptr) {
491 // These special java.lang.Module oops are created in Java code. They are not
492 // defined via Modules::define_module(), so they don't have a ModuleEntry:
493 // java.lang.Module::ALL_UNNAMED_MODULE
494 // java.lang.Module::EVERYONE_MODULE
495 // jdk.internal.loader.ClassLoaders$BootClassLoader::unnamedModule
496 log_info(cds, module)("Archived java.lang.Module oop " PTR_FORMAT " with no ModuleEntry*", p2i(orig_module_obj));
497 assert(java_lang_Module::name(orig_module_obj) == nullptr, "must be unnamed");
498 } else {
499 // This java.lang.Module oop has an ModuleEntry*. Check if the latter is archived.
500 if (log_is_enabled(Info, cds, module)) {
501 ResourceMark rm;
502 LogStream ls(Log(cds, module)::info());
503 ls.print("Archived java.lang.Module oop " PTR_FORMAT " for ", p2i(orig_module_obj));
504 orig_module_ent->print(&ls);
505 }
506
507 // We only archive the default module graph, which should contain only java.lang.Module oops
508 // for the 3 built-in loaders (boot/platform/system)
509 ClassLoaderData* loader_data = orig_module_ent->loader_data();
510 assert(loader_data->is_builtin_class_loader_data(), "must be");
511
512 if (orig_module_ent->name() != nullptr) {
513 // For each named module, we archive both the java.lang.Module oop and the ModuleEntry.
514 assert(orig_module_ent->has_been_archived(), "sanity");
515 } else {
516 // We only archive two unnamed module oops (for platform and system loaders). These do NOT have an archived
517 // ModuleEntry.
518 //
519 // At runtime, these oops are fetched from java_lang_ClassLoader::unnamedModule(loader) and
520 // are initialized in ClassLoaderData::ClassLoaderData() => ModuleEntry::create_unnamed_module(), where
521 // a new ModuleEntry is allocated.
522 assert(!loader_data->is_boot_class_loader_data(), "unnamed module for boot loader should be not archived");
523 assert(!orig_module_ent->has_been_archived(), "sanity");
524
525 if (SystemDictionary::is_platform_class_loader(loader_data->class_loader())) {
526 assert(!_seen_platform_unnamed_module, "only once");
527 _seen_platform_unnamed_module = true;
528 } else if (SystemDictionary::is_system_class_loader(loader_data->class_loader())) {
529 assert(!_seen_system_unnamed_module, "only once");
530 _seen_system_unnamed_module = true;
531 } else {
532 // The java.lang.Module oop and ModuleEntry of the unnamed module of the boot loader are
533 // not in the archived module graph. These are always allocated at runtime.
534 ShouldNotReachHere();
535 }
536 }
537 }
538 }
539
540 void Modules::verify_archived_modules() {
541 ModuleEntry::verify_archived_module_entries();
542 }
543
544 char* Modules::_archived_main_module_name = nullptr;
545 char* Modules::_archived_addmods_names = nullptr;
546 char* Modules::_archived_native_access_flags = nullptr;
547
548 void Modules::dump_main_module_name() {
549 const char* module_name = Arguments::get_property("jdk.module.main");
550 if (module_name != nullptr) {
551 _archived_main_module_name = ArchiveBuilder::current()->ro_strdup(module_name);
552 }
553 }
554
555 void Modules::check_archived_flag_consistency(char* archived_flag, const char* runtime_flag, const char* property) {
556 log_info(cds)("%s %s", property,
557 archived_flag != nullptr ? archived_flag : "(null)");
558 bool disable = false;
559 if (runtime_flag == nullptr) {
560 if (archived_flag != nullptr) {
561 log_info(cds)("Mismatched values for property %s: %s specified during dump time but not during runtime", property, archived_flag);
562 disable = true;
563 }
564 } else {
565 if (archived_flag == nullptr) {
566 log_info(cds)("Mismatched values for property %s: %s specified during runtime but not during dump time", property, runtime_flag);
567 disable = true;
568 } else if (strcmp(runtime_flag, archived_flag) != 0) {
569 log_info(cds)("Mismatched values for property %s: runtime %s dump time %s", property, runtime_flag, archived_flag);
570 disable = true;
571 }
572 }
573
574 if (disable) {
575 log_info(cds)("Disabling optimized module handling");
576 CDSConfig::stop_using_optimized_module_handling();
577 }
578 log_info(cds)("optimized module handling: %s", CDSConfig::is_using_optimized_module_handling() ? "enabled" : "disabled");
579 log_info(cds)("full module graph: %s", CDSConfig::is_using_full_module_graph() ? "enabled" : "disabled");
580 }
581
582 void Modules::dump_archived_module_info() {
583 // Write module name into archive
584 CDS_JAVA_HEAP_ONLY(Modules::dump_main_module_name();)
585 // Write module names from --add-modules into archive
586 CDS_JAVA_HEAP_ONLY(Modules::dump_addmods_names();)
587 // Write native enable-native-access flag into archive
588 CDS_JAVA_HEAP_ONLY(Modules::dump_native_access_flag());
589 }
590
591 void Modules::serialize_archived_module_info(SerializeClosure* soc) {
592 CDS_JAVA_HEAP_ONLY(Modules::serialize(soc);)
593 CDS_JAVA_HEAP_ONLY(Modules::serialize_addmods_names(soc);)
594 CDS_JAVA_HEAP_ONLY(Modules::serialize_native_access_flags(soc);)
595 }
596
597 void Modules::serialize(SerializeClosure* soc) {
598 soc->do_ptr(&_archived_main_module_name);
599 if (soc->reading()) {
600 const char* runtime_main_module = Arguments::get_property("jdk.module.main");
601 log_info(cds)("_archived_main_module_name %s",
602 _archived_main_module_name != nullptr ? _archived_main_module_name : "(null)");
603
604 check_archived_flag_consistency(_archived_main_module_name, runtime_main_module, "jdk.module.main");
605
606 // Don't hold onto the pointer, in case we might decide to unmap the archive.
607 _archived_main_module_name = nullptr;
608 }
609 }
610
611 void Modules::dump_native_access_flag() {
612 ResourceMark rm;
613 const char* native_access_names = get_native_access_flags_as_sorted_string();
614 if (native_access_names != nullptr) {
615 _archived_native_access_flags = ArchiveBuilder::current()->ro_strdup(native_access_names);
616 }
617 }
618
619 // Caller needs ResourceMark
620 const char* Modules::get_native_access_flags_as_sorted_string() {
621 return get_numbered_property_as_sorted_string("jdk.module.enable.native.access");
622 }
623
624 void Modules::serialize_native_access_flags(SerializeClosure* soc) {
625 soc->do_ptr(&_archived_native_access_flags);
626 if (soc->reading()) {
627 ResourceMark rm;
628 check_archived_flag_consistency(_archived_native_access_flags, get_native_access_flags_as_sorted_string(), "jdk.module.enable.native.access");
629
630 // Don't hold onto the pointer, in case we might decide to unmap the archive.
631 _archived_native_access_flags = nullptr;
632 }
633 }
634
635 void Modules::dump_addmods_names() {
636 ResourceMark rm;
637 const char* addmods_names = get_addmods_names_as_sorted_string();
638 if (addmods_names != nullptr) {
639 _archived_addmods_names = ArchiveBuilder::current()->ro_strdup(addmods_names);
640 }
641 }
642
643 // Caller needs ResourceMark
644 const char* Modules::get_addmods_names_as_sorted_string() {
645 return get_numbered_property_as_sorted_string("jdk.module.addmods");
646 }
647
648 void Modules::serialize_addmods_names(SerializeClosure* soc) {
649 soc->do_ptr(&_archived_addmods_names);
650 if (soc->reading()) {
651 ResourceMark rm;
652 check_archived_flag_consistency(_archived_addmods_names, get_addmods_names_as_sorted_string(), "jdk.module.addmods");
653
654 // Don't hold onto the pointer, in case we might decide to unmap the archive.
655 _archived_addmods_names = nullptr;
656 }
657 }
658
659 // Caller needs ResourceMark
660 const char* Modules::get_numbered_property_as_sorted_string(const char* property) {
661 // theoretical string size limit for decimal int, but the following loop will end much sooner due to
662 // OS command-line size limit.
663 const int max_digits = 10;
664 const int extra_symbols_count = 2; // includes '.', '\0'
665 size_t prop_len = strlen(property) + max_digits + extra_symbols_count;
666 char* prop_name = resource_allocate_bytes(prop_len);
667 GrowableArray<const char*> list;
668 for (unsigned int i = 0;; i++) {
669 jio_snprintf(prop_name, prop_len, "%s.%d", property, i);
670 const char* prop_value = Arguments::get_property(prop_name);
671 if (prop_value == nullptr) {
672 break;
673 }
674 char* p = resource_allocate_bytes(strlen(prop_value) + 1);
675 strcpy(p, prop_value);
676 while (*p == ',') p++; // skip leading commas
677 while (*p) {
678 char* next = strchr(p, ',');
679 if (next == nullptr) {
680 // no more commas, p is the last element
681 list.append(p);
682 break;
683 } else {
684 *next = 0;
685 list.append(p);
686 p = next + 1;
687 }
688 }
689 }
690
691 // Example:
692 // --add-modules=java.compiler --add-modules=java.base,java.base,,
693 //
694 // list[0] = "java.compiler"
695 // list[1] = "java.base"
696 // list[2] = "java.base"
697 // list[3] = ""
698 // list[4] = ""
699 list.sort(ClassLoaderExt::compare_module_names);
700
701 const char* prefix = "";
702 stringStream st;
703 const char* last_string = ""; // This also filters out all empty strings
704 for (int i = 0; i < list.length(); i++) {
705 const char* m = list.at(i);
706 if (strcmp(m, last_string) != 0) { // filter out duplicates
707 st.print("%s%s", prefix, m);
708 last_string = m;
709 prefix = ",";
710 }
711 }
712
713 return (st.size() > 0) ? st.as_string() : nullptr; // Example: "java.base,java.compiler"
714 }
715
716 void Modules::define_archived_modules(Handle h_platform_loader, Handle h_system_loader, TRAPS) {
717 assert(CDSConfig::is_using_full_module_graph(), "must be");
718
719 // We don't want the classes used by the archived full module graph to be redefined by JVMTI.
720 // Luckily, such classes are loaded in the JVMTI "early" phase, and CDS is disabled if a JVMTI
721 // agent wants to redefine classes in this phase.
722 JVMTI_ONLY(assert(JvmtiExport::is_early_phase(), "must be"));
723 assert(!(JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()),
724 "CDS should be disabled if early class hooks are enabled");
725
726 Handle java_base_module(THREAD, ClassLoaderDataShared::restore_archived_oops_for_null_class_loader_data());
727 // Patch any previously loaded class's module field with java.base's java.lang.Module.
728 ModuleEntryTable::patch_javabase_entries(THREAD, java_base_module);
729
730 if (h_platform_loader.is_null()) {
731 THROW_MSG(vmSymbols::java_lang_NullPointerException(), "Null platform loader object");
732 }
733
734 if (h_system_loader.is_null()) {
735 THROW_MSG(vmSymbols::java_lang_NullPointerException(), "Null system loader object");
736 }
737
738 ClassLoaderData* platform_loader_data = SystemDictionary::register_loader(h_platform_loader);
739 SystemDictionary::set_platform_loader(platform_loader_data);
740 ClassLoaderDataShared::restore_java_platform_loader_from_archive(platform_loader_data);
741
742 ClassLoaderData* system_loader_data = SystemDictionary::register_loader(h_system_loader);
743 SystemDictionary::set_system_loader(system_loader_data);
744 // system_loader_data here is always an instance of jdk.internal.loader.ClassLoader$AppClassLoader.
745 // However, if -Djava.system.class.loader=xxx is specified, java_platform_loader() would
746 // be an instance of a user-defined class, so make sure this never happens.
747 assert(Arguments::get_property("java.system.class.loader") == nullptr,
748 "archived full module should have been disabled if -Djava.system.class.loader is specified");
749 ClassLoaderDataShared::restore_java_system_loader_from_archive(system_loader_data);
750 }
751
752 void Modules::check_cds_restrictions(TRAPS) {
753 if (CDSConfig::is_dumping_full_module_graph() && Universe::is_module_initialized()) {
754 THROW_MSG(vmSymbols::java_lang_UnsupportedOperationException(),
755 "During -Xshare:dump, module system cannot be modified after it's initialized");
756 }
757 }
758 #endif // INCLUDE_CDS_JAVA_HEAP
759
760 void Modules::set_bootloader_unnamed_module(Handle module, TRAPS) {
761 ResourceMark rm(THREAD);
762
763 if (module.is_null()) {
764 THROW_MSG(vmSymbols::java_lang_NullPointerException(), "Null module object");
765 }
766 if (!java_lang_Module::is_instance(module())) {
767 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
768 "module is not an instance of type java.lang.Module");
769 }
770
771 // Ensure that this is an unnamed module
772 oop name = java_lang_Module::name(module());
773 if (name != nullptr) {
774 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
775 "boot loader's unnamed module's java.lang.Module has a name");
776 }
777
778 // Validate java_base's loader is the boot loader.
779 oop loader = java_lang_Module::loader(module());
780 if (loader != nullptr) {
781 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
782 "Class loader must be the boot class loader");
783 }
784
785 log_debug(module)("set_bootloader_unnamed_module(): recording unnamed module for boot loader");
786
787 // Set java.lang.Module for the boot loader's unnamed module
788 ClassLoaderData* boot_loader_data = ClassLoaderData::the_null_class_loader_data();
789 ModuleEntry* unnamed_module = boot_loader_data->unnamed_module();
790 assert(unnamed_module != nullptr, "boot loader's unnamed ModuleEntry not defined");
791 unnamed_module->set_module(boot_loader_data->add_handle(module));
792 // Store pointer to the ModuleEntry in the unnamed module's java.lang.Module object.
793 java_lang_Module::set_module_entry(module(), unnamed_module);
794 }
795
796 void Modules::add_module_exports(Handle from_module, jstring package_name, Handle to_module, TRAPS) {
797 check_cds_restrictions(CHECK);
798
799 if (package_name == nullptr) {
800 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
801 "package is null");
802 }
803 if (from_module.is_null()) {
804 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
805 "from_module is null");
806 }
807 ModuleEntry* from_module_entry = get_module_entry(from_module, CHECK);
808 if (from_module_entry == nullptr) {
809 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
810 "from_module cannot be found");
811 }
812
813 // All packages in unnamed and open modules are exported by default.
814 if (!from_module_entry->is_named() || from_module_entry->is_open()) return;
815
816 ModuleEntry* to_module_entry;
817 if (to_module.is_null()) {
818 to_module_entry = nullptr; // It's an unqualified export.
819 } else {
820 to_module_entry = get_module_entry(to_module, CHECK);
821 if (to_module_entry == nullptr) {
822 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
823 "to_module is invalid");
824 }
825 }
826
827 PackageEntry* package_entry = nullptr;
828 char buf[128];
829 int package_len;
830
831 ResourceMark rm(THREAD);
832 const char* pkg = as_internal_package(JNIHandles::resolve_non_null(package_name), buf, sizeof(buf), package_len);
833 {
834 MutexLocker ml(THREAD, Module_lock);
835 package_entry = get_locked_package_entry(from_module_entry, pkg, package_len);
836 // Do nothing if modules are the same
837 // If the package is not found we'll throw an exception later
838 if (from_module_entry != to_module_entry &&
839 package_entry != nullptr) {
840 package_entry->set_exported(to_module_entry);
841 }
842 }
843
844 // Handle errors and logging outside locked section
845 if (package_entry == nullptr) {
846 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
847 err_msg("Package %s not found in from_module %s",
848 pkg != nullptr ? pkg : "",
849 from_module_entry->name()->as_C_string()));
850 }
851
852 if (log_is_enabled(Debug, module)) {
853 log_debug(module)("add_module_exports(): package %s in module %s is exported to module %s",
854 package_entry->name()->as_C_string(),
855 from_module_entry->name()->as_C_string(),
856 to_module_entry == nullptr ? "null" :
857 to_module_entry->is_named() ?
858 to_module_entry->name()->as_C_string() : UNNAMED_MODULE);
859 }
860 }
861
862
863 void Modules::add_module_exports_qualified(Handle from_module, jstring package,
864 Handle to_module, TRAPS) {
865 check_cds_restrictions(CHECK);
866 if (to_module.is_null()) {
867 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
868 "to_module is null");
869 }
870 add_module_exports(from_module, package, to_module, CHECK);
871 }
872
873 void Modules::add_reads_module(Handle from_module, Handle to_module, TRAPS) {
874 check_cds_restrictions(CHECK);
875 if (from_module.is_null()) {
876 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
877 "from_module is null");
878 }
879
880 ModuleEntry* from_module_entry = get_module_entry(from_module, CHECK);
881 if (from_module_entry == nullptr) {
882 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
883 "from_module is not valid");
884 }
885
886 ModuleEntry* to_module_entry;
887 if (!to_module.is_null()) {
888 to_module_entry = get_module_entry(to_module, CHECK);
889 if (to_module_entry == nullptr) {
890 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
891 "to_module is invalid");
892 }
893 } else {
894 to_module_entry = nullptr;
895 }
896
897 ResourceMark rm(THREAD);
898 log_debug(module)("add_reads_module(): Adding read from module %s to module %s",
899 from_module_entry->is_named() ?
900 from_module_entry->name()->as_C_string() : UNNAMED_MODULE,
901 to_module_entry == nullptr ? "all unnamed" :
902 (to_module_entry->is_named() ?
903 to_module_entry->name()->as_C_string() : UNNAMED_MODULE));
904
905 // if modules are the same or if from_module is unnamed then no need to add the read.
906 if (from_module_entry != to_module_entry && from_module_entry->is_named()) {
907 from_module_entry->add_read(to_module_entry);
908 }
909 }
910
911 // This method is called by JFR and JNI.
912 jobject Modules::get_module(jclass clazz, TRAPS) {
913 assert(ModuleEntryTable::javabase_defined(),
914 "Attempt to call get_module before " JAVA_BASE_NAME " is defined");
915
916 if (clazz == nullptr) {
917 THROW_MSG_(vmSymbols::java_lang_NullPointerException(),
918 "class is null", nullptr);
919 }
920 oop mirror = JNIHandles::resolve_non_null(clazz);
921 if (mirror == nullptr) {
922 log_debug(module)("get_module(): no mirror, returning nullptr");
923 return nullptr;
924 }
925 if (!java_lang_Class::is_instance(mirror)) {
926 THROW_MSG_(vmSymbols::java_lang_IllegalArgumentException(),
927 "Invalid class", nullptr);
928 }
929
930 oop module = java_lang_Class::module(mirror);
931
932 assert(module != nullptr, "java.lang.Class module field not set");
933 assert(java_lang_Module::is_instance(module), "module is not an instance of type java.lang.Module");
934
935 LogTarget(Debug,module) lt;
936 if (lt.is_enabled()) {
937 ResourceMark rm(THREAD);
938 LogStream ls(lt);
939 Klass* klass = java_lang_Class::as_Klass(mirror);
940 oop module_name = java_lang_Module::name(module);
941 if (module_name != nullptr) {
942 ls.print("get_module(): module ");
943 java_lang_String::print(module_name, tty);
944 } else {
945 ls.print("get_module(): Unnamed Module");
946 }
947 if (klass != nullptr) {
948 ls.print_cr(" for class %s", klass->external_name());
949 } else {
950 ls.print_cr(" for primitive class");
951 }
952 }
953
954 return JNIHandles::make_local(THREAD, module);
955 }
956
957 oop Modules::get_named_module(Handle h_loader, const char* package_name) {
958 assert(ModuleEntryTable::javabase_defined(),
959 "Attempt to call get_named_module before " JAVA_BASE_NAME " is defined");
960 assert(h_loader.is_null() || java_lang_ClassLoader::is_subclass(h_loader->klass()),
961 "Class loader is not a subclass of java.lang.ClassLoader");
962 assert(package_name != nullptr, "the package_name should not be null");
963
964 if (strlen(package_name) == 0) {
965 return nullptr;
966 }
967 TempNewSymbol package_sym = SymbolTable::new_symbol(package_name);
968 const PackageEntry* const pkg_entry =
969 get_package_entry_by_name(package_sym, h_loader);
970 const ModuleEntry* const module_entry = (pkg_entry != nullptr ? pkg_entry->module() : nullptr);
971
972 if (module_entry != nullptr && module_entry->module() != nullptr && module_entry->is_named()) {
973 return module_entry->module();
974 }
975 return nullptr;
976 }
977
978 // Export package in module to all unnamed modules.
979 void Modules::add_module_exports_to_all_unnamed(Handle module, jstring package_name, TRAPS) {
980 check_cds_restrictions(CHECK);
981 if (module.is_null()) {
982 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
983 "module is null");
984 }
985 if (package_name == nullptr) {
986 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
987 "package is null");
988 }
989 ModuleEntry* module_entry = get_module_entry(module, CHECK);
990 if (module_entry == nullptr) {
991 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
992 "module is invalid");
993 }
994
995 // No-op for unnamed module and open modules
996 if (!module_entry->is_named() || module_entry->is_open())
997 return;
998
999 ResourceMark rm(THREAD);
1000 char buf[128];
1001 int pkg_len;
1002 const char* pkg = as_internal_package(JNIHandles::resolve_non_null(package_name), buf, sizeof(buf), pkg_len);
1003 PackageEntry* package_entry = nullptr;
1004 {
1005 MutexLocker m1(THREAD, Module_lock);
1006 package_entry = get_locked_package_entry(module_entry, pkg, pkg_len);
1007
1008 // Mark package as exported to all unnamed modules.
1009 if (package_entry != nullptr) {
1010 package_entry->set_is_exported_allUnnamed();
1011 }
1012 }
1013
1014 // Handle errors and logging outside locked section
1015 if (package_entry == nullptr) {
1016 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
1017 err_msg("Package %s not found in module %s",
1018 pkg != nullptr ? pkg : "",
1019 module_entry->name()->as_C_string()));
1020 }
1021
1022 if (log_is_enabled(Debug, module)) {
1023 log_debug(module)("add_module_exports_to_all_unnamed(): package %s in module"
1024 " %s is exported to all unnamed modules",
1025 package_entry->name()->as_C_string(),
1026 module_entry->name()->as_C_string());
1027 }
1028 }