1 /*
2 * Copyright (c) 2016, 2024, 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 "precompiled.hpp"
26 #include "cds/archiveBuilder.hpp"
27 #include "cds/cdsConfig.hpp"
28 #include "cds/metaspaceShared.hpp"
29 #include "classfile/classFileParser.hpp"
30 #include "classfile/classLoader.hpp"
31 #include "classfile/classLoaderData.inline.hpp"
32 #include "classfile/classLoaderDataShared.hpp"
33 #include "classfile/classLoaderExt.hpp"
34 #include "classfile/javaAssertions.hpp"
35 #include "classfile/javaClasses.hpp"
36 #include "classfile/javaClasses.inline.hpp"
37 #include "classfile/moduleEntry.hpp"
38 #include "classfile/modules.hpp"
39 #include "classfile/packageEntry.hpp"
40 #include "classfile/stringTable.hpp"
41 #include "classfile/symbolTable.hpp"
42 #include "classfile/systemDictionary.hpp"
43 #include "classfile/vmClasses.hpp"
44 #include "classfile/vmSymbols.hpp"
45 #include "jvm.h"
46 #include "logging/log.hpp"
47 #include "logging/logStream.hpp"
48 #include "memory/resourceArea.hpp"
49 #include "prims/jvmtiExport.hpp"
50 #include "runtime/arguments.hpp"
51 #include "runtime/globals_extension.hpp"
52 #include "runtime/handles.inline.hpp"
53 #include "runtime/javaCalls.hpp"
54 #include "runtime/jniHandles.inline.hpp"
55 #include "utilities/formatBuffer.hpp"
56 #include "utilities/stringUtils.hpp"
57 #include "utilities/utf8.hpp"
58
59 static bool verify_module_name(const char *module_name, int len) {
60 assert(module_name != nullptr, "invariant");
61 return (len > 0 && len <= Symbol::max_length());
62 }
63
64 static bool verify_package_name(const char* package_name, int len) {
65 assert(package_name != nullptr, "Package name derived from non-null jstring can't be null");
66 return (len > 0 && len <= Symbol::max_length() &&
67 ClassFileParser::verify_unqualified_name(package_name, len,
68 ClassFileParser::LegalClass));
69 }
70
71 static char* get_module_name(oop module, int& len, TRAPS) {
72 oop name_oop = java_lang_Module::name(module);
73 if (name_oop == nullptr) {
74 THROW_MSG_NULL(vmSymbols::java_lang_NullPointerException(), "Null module name");
75 }
76 size_t utf8_len;
77 char* module_name = java_lang_String::as_utf8_string(name_oop, utf8_len);
78 len = checked_cast<int>(utf8_len); // module names are < 64K
79 if (!verify_module_name(module_name, len)) {
80 THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(),
81 err_msg("Invalid module name: %s", module_name));
82 }
83 return module_name;
84 }
85
86 static Symbol* as_symbol(jstring str_object) {
87 if (str_object == nullptr) {
88 return nullptr;
89 }
90 size_t len;
91 char* str = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(str_object), len);
92 return SymbolTable::new_symbol(str, checked_cast<int>(len));
93 }
94
95 ModuleEntryTable* Modules::get_module_entry_table(Handle h_loader) {
96 // This code can be called during start-up, before the classLoader's classLoader data got
97 // created. So, call register_loader() to make sure the classLoader data gets created.
98 ClassLoaderData *loader_cld = SystemDictionary::register_loader(h_loader);
99 return loader_cld->modules();
100 }
101
102 static PackageEntryTable* get_package_entry_table(Handle h_loader) {
103 // This code can be called during start-up, before the classLoader's classLoader data got
104 // created. So, call register_loader() to make sure the classLoader data gets created.
105 ClassLoaderData *loader_cld = SystemDictionary::register_loader(h_loader);
106 return loader_cld->packages();
107 }
108
109 static ModuleEntry* get_module_entry(Handle module, TRAPS) {
110 if (!java_lang_Module::is_instance(module())) {
111 THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(),
112 "module is not an instance of type java.lang.Module");
113 }
114 return java_lang_Module::module_entry(module());
115 }
116
117
118 static PackageEntry* get_locked_package_entry(ModuleEntry* module_entry, const char* package_name, int len) {
119 assert(Module_lock->owned_by_self(), "should have the Module_lock");
120 assert(package_name != nullptr, "Precondition");
121 TempNewSymbol pkg_symbol = SymbolTable::new_symbol(package_name, len);
122 PackageEntryTable* package_entry_table = module_entry->loader_data()->packages();
123 assert(package_entry_table != nullptr, "Unexpected null package entry table");
124 PackageEntry* package_entry = package_entry_table->locked_lookup_only(pkg_symbol);
125 assert(package_entry == nullptr || package_entry->module() == module_entry, "Unexpectedly found a package linked to another module");
126 return package_entry;
127 }
128
129 static PackageEntry* get_package_entry_by_name(Symbol* package, Handle h_loader) {
130 if (package != nullptr) {
131 PackageEntryTable* const package_entry_table =
132 get_package_entry_table(h_loader);
133 assert(package_entry_table != nullptr, "Unexpected null package entry table");
134 return package_entry_table->lookup_only(package);
135 }
136 return nullptr;
137 }
138
139 bool Modules::is_package_defined(Symbol* package, Handle h_loader) {
140 PackageEntry* res = get_package_entry_by_name(package, h_loader);
141 return res != nullptr;
142 }
143
144 // Converts the String oop to an internal package
145 // Will use the provided buffer if it's sufficiently large, otherwise allocates
146 // a resource array
147 // The length of the resulting string will be assigned to utf8_len
148 static const char* as_internal_package(oop package_string, char* buf, size_t buflen, int& utf8_len) {
149 size_t full_utf8_len;
150 char* package_name = java_lang_String::as_utf8_string_full(package_string, buf, buflen, full_utf8_len);
151 utf8_len = checked_cast<int>(full_utf8_len); // package names are < 64K
152
153 // Turn all '/'s into '.'s
154 for (int index = 0; index < utf8_len; index++) {
155 if (package_name[index] == JVM_SIGNATURE_DOT) {
156 package_name[index] = JVM_SIGNATURE_SLASH;
157 }
158 }
159 return package_name;
160 }
161
162 static void define_javabase_module(Handle module_handle, jstring version, jstring location,
163 objArrayHandle pkgs, int num_packages, TRAPS) {
164 ResourceMark rm(THREAD);
165
166 // Obtain java.base's module version
167 TempNewSymbol version_symbol = as_symbol(version);
168
169 // Obtain java.base's location
170 TempNewSymbol location_symbol = as_symbol(location);
171
172 // Check that the packages are syntactically ok.
173 char buf[128];
174 GrowableArray<Symbol*>* pkg_list = new GrowableArray<Symbol*>(num_packages);
175 for (int x = 0; x < num_packages; x++) {
176 oop pkg_str = pkgs->obj_at(x);
177
178 if (pkg_str == nullptr || pkg_str->klass() != vmClasses::String_klass()) {
179 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
180 err_msg("Bad package name"));
181 }
182
183 int package_len;
184 const char* package_name = as_internal_package(pkg_str, buf, sizeof(buf), package_len);
185 if (!verify_package_name(package_name, package_len)) {
186 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
187 err_msg("Invalid package name: %s for module: " JAVA_BASE_NAME, package_name));
188 }
189 Symbol* pkg_symbol = SymbolTable::new_symbol(package_name, package_len);
190 pkg_list->append(pkg_symbol);
191 }
192
193 // Validate java_base's loader is the boot loader.
194 oop loader = java_lang_Module::loader(module_handle());
195 if (loader != nullptr) {
196 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
197 "Class loader must be the boot class loader");
198 }
199 Handle h_loader(THREAD, loader);
200
201 // Ensure the boot loader's PackageEntryTable has been created
202 PackageEntryTable* package_table = get_package_entry_table(h_loader);
203 assert(pkg_list->length() == 0 || package_table != nullptr, "Bad package_table");
204
205 // Ensure java.base's ModuleEntry has been created
206 assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, "No ModuleEntry for " JAVA_BASE_NAME);
207
208 bool duplicate_javabase = false;
209 {
210 MutexLocker m1(THREAD, Module_lock);
211
212 if (ModuleEntryTable::javabase_defined()) {
213 duplicate_javabase = true;
214 } else {
215
216 // Verify that all java.base packages created during bootstrapping are in
217 // pkg_list. If any are not in pkg_list, than a non-java.base class was
218 // loaded erroneously pre java.base module definition.
219 package_table->verify_javabase_packages(pkg_list);
220
221 // loop through and add any new packages for java.base
222 for (int x = 0; x < pkg_list->length(); x++) {
223 // Some of java.base's packages were added early in bootstrapping, ignore duplicates.
224 package_table->locked_create_entry_if_absent(pkg_list->at(x),
225 ModuleEntryTable::javabase_moduleEntry());
226 assert(package_table->locked_lookup_only(pkg_list->at(x)) != nullptr,
227 "Unable to create a " JAVA_BASE_NAME " package entry");
228 // Unable to have a GrowableArray of TempNewSymbol. Must decrement the refcount of
229 // the Symbol* that was created above for each package. The refcount was incremented
230 // by SymbolTable::new_symbol and as well by the PackageEntry creation.
231 pkg_list->at(x)->decrement_refcount();
232 }
233
234 // Finish defining java.base's ModuleEntry
235 ModuleEntryTable::finalize_javabase(module_handle, version_symbol, location_symbol);
236 }
237 }
238 if (duplicate_javabase) {
239 THROW_MSG(vmSymbols::java_lang_InternalError(),
240 "Module " JAVA_BASE_NAME " is already defined");
241 }
242
243 // Only the thread that actually defined the base module will get here,
244 // so no locking is needed.
245
246 // Patch any previously loaded class's module field with java.base's java.lang.Module.
247 ModuleEntryTable::patch_javabase_entries(THREAD, module_handle);
248
249 log_info(module, load)(JAVA_BASE_NAME " location: %s",
250 location_symbol != nullptr ? location_symbol->as_C_string() : "nullptr");
251 log_debug(module)("define_javabase_module(): Definition of module: "
252 JAVA_BASE_NAME ", version: %s, location: %s, package #: %d",
253 version_symbol != nullptr ? version_symbol->as_C_string() : "nullptr",
254 location_symbol != nullptr ? location_symbol->as_C_string() : "nullptr",
255 pkg_list->length());
256
257 // packages defined to java.base
258 if (log_is_enabled(Trace, module)) {
259 for (int x = 0; x < pkg_list->length(); x++) {
260 log_trace(module)("define_javabase_module(): creation of package %s for module " JAVA_BASE_NAME,
261 (pkg_list->at(x))->as_C_string());
262 }
263 }
264 }
265
266 // Caller needs ResourceMark.
267 static void throw_dup_pkg_exception(const char* module_name, PackageEntry* package, TRAPS) {
268 const char* package_name = package->name()->as_C_string();
269 if (package->module()->is_named()) {
270 THROW_MSG(vmSymbols::java_lang_IllegalStateException(),
271 err_msg("Package %s for module %s is already in another module, %s, defined to the class loader",
272 package_name, module_name, package->module()->name()->as_C_string()));
273 } else {
274 THROW_MSG(vmSymbols::java_lang_IllegalStateException(),
275 err_msg("Package %s for module %s is already in the unnamed module defined to the class loader",
276 package_name, module_name));
277 }
278 }
279
280 void Modules::define_module(Handle module, jboolean is_open, jstring version,
281 jstring location, jobjectArray packages, TRAPS) {
282 check_cds_restrictions(CHECK);
283 ResourceMark rm(THREAD);
284
285 if (module.is_null()) {
286 THROW_MSG(vmSymbols::java_lang_NullPointerException(), "Null module object");
287 }
288
289 if (!java_lang_Module::is_instance(module())) {
290 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
291 "module is not an instance of type java.lang.Module");
292 }
293
294 int module_name_len;
295 char* module_name = get_module_name(module(), module_name_len, CHECK);
296 if (module_name == nullptr) {
297 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
298 "Module name cannot be null");
299 }
300
301 // Resolve packages
302 objArrayHandle packages_h(THREAD, objArrayOop(JNIHandles::resolve(packages)));
303 int num_packages = (packages_h.is_null() ? 0 : packages_h->length());
304
305 // Special handling of java.base definition
306 if (strcmp(module_name, JAVA_BASE_NAME) == 0) {
307 assert(is_open == JNI_FALSE, "java.base module cannot be open");
308 define_javabase_module(module, version, location, packages_h, num_packages, CHECK);
309 return;
310 }
311
312 oop loader = java_lang_Module::loader(module());
313 Handle h_loader = Handle(THREAD, loader);
314 // define_module can be called during start-up, before the class loader's ClassLoaderData
315 // has been created. SystemDictionary::register_loader ensures creation, if needed.
316 ClassLoaderData* loader_data = SystemDictionary::register_loader(h_loader);
317 assert(loader_data != nullptr, "class loader data shouldn't be null");
318
319 // Only modules defined to either the boot or platform class loader, can define a "java/" package.
320 bool java_pkg_disallowed = !h_loader.is_null() &&
321 !SystemDictionary::is_platform_class_loader(h_loader());
322
323 // Check that the list of packages has no duplicates and that the
324 // packages are syntactically ok.
325 char buf[128];
326 GrowableArray<Symbol*>* pkg_list = new GrowableArray<Symbol*>(num_packages);
327 for (int x = 0; x < num_packages; x++) {
328 oop pkg_str = packages_h->obj_at(x);
329 if (pkg_str == nullptr || pkg_str->klass() != vmClasses::String_klass()) {
330 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
331 err_msg("Bad package name"));
332 }
333
334 int package_len;
335 const char* package_name = as_internal_package(pkg_str, buf, sizeof(buf), package_len);
336 if (!verify_package_name(package_name, package_len)) {
337 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
338 err_msg("Invalid package name: %s for module: %s",
339 package_name, module_name));
340 }
341
342 // Only modules defined to either the boot or platform class loader, can define a "java/" package.
343 if (java_pkg_disallowed &&
344 (strncmp(package_name, JAVAPKG, JAVAPKG_LEN) == 0 &&
345 (package_name[JAVAPKG_LEN] == JVM_SIGNATURE_SLASH || package_name[JAVAPKG_LEN] == '\0'))) {
346 const char* class_loader_name = loader_data->loader_name_and_id();
347 size_t pkg_len = strlen(package_name);
348 char* pkg_name = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, pkg_len + 1);
349 strncpy(pkg_name, package_name, pkg_len + 1);
350 StringUtils::replace_no_expand(pkg_name, "/", ".");
351 const char* msg_text1 = "Class loader (instance of): ";
352 const char* msg_text2 = " tried to define prohibited package name: ";
353 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + pkg_len + 1;
354 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
355 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, pkg_name);
356 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), message);
357 }
358
359 Symbol* pkg_symbol = SymbolTable::new_symbol(package_name, package_len);
360 pkg_list->append(pkg_symbol);
361 }
362
363 ModuleEntryTable* module_table = get_module_entry_table(h_loader);
364 assert(module_table != nullptr, "module entry table shouldn't be null");
365
366 // Create symbol* entry for module name.
367 TempNewSymbol module_symbol = SymbolTable::new_symbol(module_name, module_name_len);
368
369 bool dupl_modules = false;
370
371 // Create symbol for module version.
372 TempNewSymbol version_symbol = as_symbol(version);
373
374 // Create symbol* entry for module location.
375 TempNewSymbol location_symbol = as_symbol(location);
376
377 PackageEntryTable* package_table = nullptr;
378 PackageEntry* existing_pkg = nullptr;
379 {
380 MutexLocker ml(THREAD, Module_lock);
381
382 if (num_packages > 0) {
383 package_table = get_package_entry_table(h_loader);
384 assert(package_table != nullptr, "Missing package_table");
385
386 // Check that none of the packages exist in the class loader's package table.
387 for (int x = 0; x < pkg_list->length(); x++) {
388 existing_pkg = package_table->locked_lookup_only(pkg_list->at(x));
389 if (existing_pkg != nullptr) {
390 // This could be because the module was already defined. If so,
391 // report that error instead of the package error.
392 if (module_table->lookup_only(module_symbol) != nullptr) {
393 dupl_modules = true;
394 }
395 break;
396 }
397 }
398 } // if (num_packages > 0)...
399
400 // Add the module and its packages.
401 if (!dupl_modules && existing_pkg == nullptr) {
402 if (module_table->lookup_only(module_symbol) == nullptr) {
403 // Create the entry for this module in the class loader's module entry table.
404 ModuleEntry* module_entry = module_table->locked_create_entry(module,
405 (is_open == JNI_TRUE), module_symbol,
406 version_symbol, location_symbol, loader_data);
407 assert(module_entry != nullptr, "module_entry creation failed");
408
409 // Add the packages.
410 assert(pkg_list->length() == 0 || package_table != nullptr, "Bad package table");
411 for (int y = 0; y < pkg_list->length(); y++) {
412 package_table->locked_create_entry(pkg_list->at(y), module_entry);
413
414 // Unable to have a GrowableArray of TempNewSymbol. Must decrement the refcount of
415 // the Symbol* that was created above for each package. The refcount was incremented
416 // by SymbolTable::new_symbol and as well by the PackageEntry creation.
417 pkg_list->at(y)->decrement_refcount();
418 }
419
420 // Store pointer to ModuleEntry record in java.lang.Module object.
421 java_lang_Module::set_module_entry(module(), module_entry);
422 } else {
423 dupl_modules = true;
424 }
425 }
426 } // Release the lock
427
428 // any errors ?
429 if (dupl_modules) {
430 THROW_MSG(vmSymbols::java_lang_IllegalStateException(),
431 err_msg("Module %s is already defined", module_name));
432 } else if (existing_pkg != nullptr) {
433 throw_dup_pkg_exception(module_name, existing_pkg, CHECK);
434 }
435
436 log_info(module, load)("%s location: %s", module_name,
437 location_symbol != nullptr ? location_symbol->as_C_string() : "null");
438 LogTarget(Debug, module) lt;
439 if (lt.is_enabled()) {
440 LogStream ls(lt);
441 ls.print("define_module(): creation of module: %s, version: %s, location: %s, ",
442 module_name, version_symbol != nullptr ? version_symbol->as_C_string() : "null",
443 location_symbol != nullptr ? location_symbol->as_C_string() : "null");
444 loader_data->print_value_on(&ls);
445 ls.print_cr(", package #: %d", pkg_list->length());
446 for (int y = 0; y < pkg_list->length(); y++) {
447 log_trace(module)("define_module(): creation of package %s for module %s",
448 (pkg_list->at(y))->as_C_string(), module_name);
449 }
450 }
451
452 // If the module is defined to the boot loader and an exploded build is being
453 // used, prepend <java.home>/modules/modules_name to the boot class path.
454 if (h_loader.is_null() && !ClassLoader::has_jrt_entry()) {
455 ClassLoader::add_to_exploded_build_list(THREAD, module_symbol);
456 }
457
458 #if COMPILER2_OR_JVMCI
459 // Special handling of jdk.incubator.vector
460 if (strcmp(module_name, "jdk.incubator.vector") == 0) {
461 if (FLAG_IS_DEFAULT(EnableVectorSupport)) {
462 FLAG_SET_DEFAULT(EnableVectorSupport, true);
463 }
464 if (EnableVectorSupport && FLAG_IS_DEFAULT(EnableVectorReboxing)) {
465 FLAG_SET_DEFAULT(EnableVectorReboxing, true);
466 }
467 if (EnableVectorSupport && EnableVectorReboxing && FLAG_IS_DEFAULT(EnableVectorAggressiveReboxing)) {
468 FLAG_SET_DEFAULT(EnableVectorAggressiveReboxing, true);
469 }
470 if (EnableVectorSupport && FLAG_IS_DEFAULT(UseVectorStubs)) {
471 FLAG_SET_DEFAULT(UseVectorStubs, true);
472 }
473 log_info(compilation)("EnableVectorSupport=%s", (EnableVectorSupport ? "true" : "false"));
474 log_info(compilation)("EnableVectorReboxing=%s", (EnableVectorReboxing ? "true" : "false"));
475 log_info(compilation)("EnableVectorAggressiveReboxing=%s", (EnableVectorAggressiveReboxing ? "true" : "false"));
476 log_info(compilation)("UseVectorStubs=%s", (UseVectorStubs ? "true" : "false"));
477 }
478 #endif // COMPILER2_OR_JVMCI
479 }
480
481 #if INCLUDE_CDS_JAVA_HEAP
482 static bool _seen_platform_unnamed_module = false;
483 static bool _seen_system_unnamed_module = false;
484
485 // Validate the states of an java.lang.Module oop to be archived.
486 //
487 // Returns true iff the oop has an archived ModuleEntry.
488 bool Modules::check_archived_module_oop(oop orig_module_obj) {
489 assert(CDSConfig::is_dumping_full_module_graph(), "must be");
490 assert(java_lang_Module::is_instance(orig_module_obj), "must be");
491
492 ModuleEntry* orig_module_ent = java_lang_Module::module_entry_raw(orig_module_obj);
493 if (orig_module_ent == nullptr) {
494 // These special java.lang.Module oops are created in Java code. They are not
495 // defined via Modules::define_module(), so they don't have a ModuleEntry:
496 // java.lang.Module::ALL_UNNAMED_MODULE
497 // java.lang.Module::EVERYONE_MODULE
498 // jdk.internal.loader.ClassLoaders$BootClassLoader::unnamedModule
499 log_info(cds, module)("Archived java.lang.Module oop " PTR_FORMAT " with no ModuleEntry*", p2i(orig_module_obj));
500 assert(java_lang_Module::name(orig_module_obj) == nullptr, "must be unnamed");
501 return false;
502 } else {
503 // This java.lang.Module oop has an ModuleEntry*. Check if the latter is archived.
504 if (log_is_enabled(Info, cds, module)) {
505 ResourceMark rm;
506 LogStream ls(Log(cds, module)::info());
507 ls.print("Archived java.lang.Module oop " PTR_FORMAT " for ", p2i(orig_module_obj));
508 orig_module_ent->print(&ls);
509 }
510
511 // We only archive the default module graph, which should contain only java.lang.Module oops
512 // for the 3 built-in loaders (boot/platform/system)
513 ClassLoaderData* loader_data = orig_module_ent->loader_data();
514 assert(loader_data->is_builtin_class_loader_data(), "must be");
515
516 if (orig_module_ent->name() != nullptr) {
517 // For each named module, we archive both the java.lang.Module oop and the ModuleEntry.
518 assert(orig_module_ent->has_been_archived(), "sanity");
519 return true;
520 } else {
521 // We only archive two unnamed module oops (for platform and system loaders). These do NOT have an archived
522 // ModuleEntry.
523 //
524 // At runtime, these oops are fetched from java_lang_ClassLoader::unnamedModule(loader) and
525 // are initialized in ClassLoaderData::ClassLoaderData() => ModuleEntry::create_unnamed_module(), where
526 // a new ModuleEntry is allocated.
527 assert(!loader_data->is_boot_class_loader_data(), "unnamed module for boot loader should be not archived");
528 assert(!orig_module_ent->has_been_archived(), "sanity");
529
530 if (SystemDictionary::is_platform_class_loader(loader_data->class_loader())) {
531 assert(!_seen_platform_unnamed_module, "only once");
532 _seen_platform_unnamed_module = true;
533 } else if (SystemDictionary::is_system_class_loader(loader_data->class_loader())) {
534 assert(!_seen_system_unnamed_module, "only once");
535 _seen_system_unnamed_module = true;
536 } else {
537 // The java.lang.Module oop and ModuleEntry of the unnamed module of the boot loader are
538 // not in the archived module graph. These are always allocated at runtime.
539 ShouldNotReachHere();
540 }
541 return false;
542 }
543 }
544 }
545
546 void Modules::update_oops_in_archived_module(oop orig_module_obj, int archived_module_root_index) {
547 // This java.lang.Module oop must have an archived ModuleEntry
548 assert(check_archived_module_oop(orig_module_obj) == true, "sanity");
549
550 // We remember the oop inside the ModuleEntry::_archived_module_index. At runtime, we use
551 // this index to reinitialize the ModuleEntry inside ModuleEntry::restore_archived_oops().
552 //
553 // ModuleEntry::verify_archived_module_entries(), called below, ensures that every archived
554 // ModuleEntry has been assigned an _archived_module_index.
555 ModuleEntry* orig_module_ent = java_lang_Module::module_entry_raw(orig_module_obj);
556 ModuleEntry::get_archived_entry(orig_module_ent)->update_oops_in_archived_module(archived_module_root_index);
557 }
558
559 void Modules::verify_archived_modules() {
560 ModuleEntry::verify_archived_module_entries();
561 }
562
563 char* Modules::_archived_main_module_name = nullptr;
564 char* Modules::_archived_addmods_names = nullptr;
565 char* Modules::_archived_native_access_flags = nullptr;
566
567 void Modules::dump_main_module_name() {
568 const char* module_name = Arguments::get_property("jdk.module.main");
569 if (module_name != nullptr) {
570 _archived_main_module_name = ArchiveBuilder::current()->ro_strdup(module_name);
571 }
572 }
573
574 void Modules::check_archived_flag_consistency(char* archived_flag, const char* runtime_flag, const char* property) {
575 log_info(cds)("%s %s", property,
576 archived_flag != nullptr ? archived_flag : "(null)");
577 bool disable = false;
578 if (runtime_flag == nullptr) {
579 if (archived_flag != nullptr) {
580 log_info(cds)("Mismatched values for property %s: %s specified during dump time but not during runtime", property, archived_flag);
581 disable = true;
582 }
583 } else {
584 if (archived_flag == nullptr) {
585 log_info(cds)("Mismatched values for property %s: %s specified during runtime but not during dump time", property, runtime_flag);
586 disable = true;
587 } else if (strcmp(runtime_flag, archived_flag) != 0) {
588 log_info(cds)("Mismatched values for property %s: runtime %s dump time %s", property, runtime_flag, archived_flag);
589 disable = true;
590 }
591 }
592
593 if (disable) {
594 log_info(cds)("Disabling optimized module handling");
595 CDSConfig::stop_using_optimized_module_handling();
596 }
597 log_info(cds)("optimized module handling: %s", CDSConfig::is_using_optimized_module_handling() ? "enabled" : "disabled");
598 log_info(cds)("full module graph: %s", CDSConfig::is_using_full_module_graph() ? "enabled" : "disabled");
599 }
600
601 void Modules::dump_archived_module_info() {
602 // Write module name into archive
603 CDS_JAVA_HEAP_ONLY(Modules::dump_main_module_name();)
604 // Write module names from --add-modules into archive
605 CDS_JAVA_HEAP_ONLY(Modules::dump_addmods_names();)
606 // Write native enable-native-access flag into archive
607 CDS_JAVA_HEAP_ONLY(Modules::dump_native_access_flag());
608 }
609
610 void Modules::serialize_archived_module_info(SerializeClosure* soc) {
611 CDS_JAVA_HEAP_ONLY(Modules::serialize(soc);)
612 CDS_JAVA_HEAP_ONLY(Modules::serialize_addmods_names(soc);)
613 CDS_JAVA_HEAP_ONLY(Modules::serialize_native_access_flags(soc);)
614 }
615
616 void Modules::serialize(SerializeClosure* soc) {
617 soc->do_ptr(&_archived_main_module_name);
618 if (soc->reading()) {
619 const char* runtime_main_module = Arguments::get_property("jdk.module.main");
620 log_info(cds)("_archived_main_module_name %s",
621 _archived_main_module_name != nullptr ? _archived_main_module_name : "(null)");
622
623 check_archived_flag_consistency(_archived_main_module_name, runtime_main_module, "jdk.module.main");
624
625 // Don't hold onto the pointer, in case we might decide to unmap the archive.
626 _archived_main_module_name = nullptr;
627 }
628 }
629
630 void Modules::dump_native_access_flag() {
631 const char* native_access_names = get_native_access_flags_as_sorted_string();
632 if (native_access_names != nullptr) {
633 _archived_native_access_flags = ArchiveBuilder::current()->ro_strdup(native_access_names);
634 }
635 }
636
637 const char* Modules::get_native_access_flags_as_sorted_string() {
638 return get_numbered_property_as_sorted_string("jdk.module.enable.native.access");
639 }
640
641 void Modules::serialize_native_access_flags(SerializeClosure* soc) {
642 soc->do_ptr(&_archived_native_access_flags);
643 if (soc->reading()) {
644 check_archived_flag_consistency(_archived_native_access_flags, get_native_access_flags_as_sorted_string(), "jdk.module.enable.native.access");
645
646 // Don't hold onto the pointer, in case we might decide to unmap the archive.
647 _archived_native_access_flags = nullptr;
648 }
649 }
650
651 void Modules::dump_addmods_names() {
652 const char* addmods_names = get_addmods_names_as_sorted_string();
653 if (addmods_names != nullptr) {
654 _archived_addmods_names = ArchiveBuilder::current()->ro_strdup(addmods_names);
655 }
656 }
657
658 const char* Modules::get_addmods_names_as_sorted_string() {
659 return get_numbered_property_as_sorted_string("jdk.module.addmods");
660 }
661
662 void Modules::serialize_addmods_names(SerializeClosure* soc) {
663 soc->do_ptr(&_archived_addmods_names);
664 if (soc->reading()) {
665 check_archived_flag_consistency(_archived_addmods_names, get_addmods_names_as_sorted_string(), "jdk.module.addmods");
666
667 // Don't hold onto the pointer, in case we might decide to unmap the archive.
668 _archived_addmods_names = nullptr;
669 }
670 }
671
672 const char* Modules::get_numbered_property_as_sorted_string(const char* property) {
673 ResourceMark rm;
674 // theoretical string size limit for decimal int, but the following loop will end much sooner due to
675 // OS command-line size limit.
676 const int max_digits = 10;
677 const int extra_symbols_count = 2; // includes '.', '\0'
678 size_t prop_len = strlen(property) + max_digits + extra_symbols_count;
679 char* prop_name = resource_allocate_bytes(prop_len);
680 GrowableArray<const char*> list;
681 for (unsigned int i = 0;; i++) {
682 jio_snprintf(prop_name, prop_len, "%s.%d", property, i);
683 const char* prop_value = Arguments::get_property(prop_name);
684 if (prop_value == nullptr) {
685 break;
686 }
687 char* p = resource_allocate_bytes(strlen(prop_value) + 1);
688 strcpy(p, prop_value);
689 while (*p == ',') p++; // skip leading commas
690 while (*p) {
691 char* next = strchr(p, ',');
692 if (next == nullptr) {
693 // no more commas, p is the last element
694 list.append(p);
695 break;
696 } else {
697 *next = 0;
698 list.append(p);
699 p = next + 1;
700 }
701 }
702 }
703
704 // Example:
705 // --add-modules=java.compiler --add-modules=java.base,java.base,,
706 //
707 // list[0] = "java.compiler"
708 // list[1] = "java.base"
709 // list[2] = "java.base"
710 // list[3] = ""
711 // list[4] = ""
712 list.sort(ClassLoaderExt::compare_module_names);
713
714 const char* prefix = "";
715 stringStream st;
716 const char* last_string = ""; // This also filters out all empty strings
717 for (int i = 0; i < list.length(); i++) {
718 const char* m = list.at(i);
719 if (strcmp(m, last_string) != 0) { // filter out duplicates
720 st.print("%s%s", prefix, m);
721 last_string = m;
722 prefix = ",";
723 }
724 }
725
726 return (st.size() > 0) ? os::strdup(st.as_string()) : nullptr; // Example: "java.base,java.compiler"
727 }
728
729 void Modules::define_archived_modules(Handle h_platform_loader, Handle h_system_loader, TRAPS) {
730 assert(CDSConfig::is_using_full_module_graph(), "must be");
731
732 // We don't want the classes used by the archived full module graph to be redefined by JVMTI.
733 // Luckily, such classes are loaded in the JVMTI "early" phase, and CDS is disabled if a JVMTI
734 // agent wants to redefine classes in this phase.
735 JVMTI_ONLY(assert(JvmtiExport::is_early_phase(), "must be"));
736 assert(!(JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()),
737 "CDS should be disabled if early class hooks are enabled");
738
739 Handle java_base_module(THREAD, ClassLoaderDataShared::restore_archived_oops_for_null_class_loader_data());
740 // Patch any previously loaded class's module field with java.base's java.lang.Module.
741 ModuleEntryTable::patch_javabase_entries(THREAD, java_base_module);
742
743 if (h_platform_loader.is_null()) {
744 THROW_MSG(vmSymbols::java_lang_NullPointerException(), "Null platform loader object");
745 }
746
747 if (h_system_loader.is_null()) {
748 THROW_MSG(vmSymbols::java_lang_NullPointerException(), "Null system loader object");
749 }
750
751 ClassLoaderData* platform_loader_data = SystemDictionary::register_loader(h_platform_loader);
752 SystemDictionary::set_platform_loader(platform_loader_data);
753 ClassLoaderDataShared::restore_java_platform_loader_from_archive(platform_loader_data);
754
755 ClassLoaderData* system_loader_data = SystemDictionary::register_loader(h_system_loader);
756 SystemDictionary::set_system_loader(system_loader_data);
757 // system_loader_data here is always an instance of jdk.internal.loader.ClassLoader$AppClassLoader.
758 // However, if -Djava.system.class.loader=xxx is specified, java_platform_loader() would
759 // be an instance of a user-defined class, so make sure this never happens.
760 assert(Arguments::get_property("java.system.class.loader") == nullptr,
761 "archived full module should have been disabled if -Djava.system.class.loader is specified");
762 ClassLoaderDataShared::restore_java_system_loader_from_archive(system_loader_data);
763 }
764
765 void Modules::check_cds_restrictions(TRAPS) {
766 if (CDSConfig::is_dumping_full_module_graph() && Universe::is_module_initialized()) {
767 THROW_MSG(vmSymbols::java_lang_UnsupportedOperationException(),
768 "During -Xshare:dump, module system cannot be modified after it's initialized");
769 }
770 }
771 #endif // INCLUDE_CDS_JAVA_HEAP
772
773 void Modules::set_bootloader_unnamed_module(Handle module, TRAPS) {
774 ResourceMark rm(THREAD);
775
776 if (module.is_null()) {
777 THROW_MSG(vmSymbols::java_lang_NullPointerException(), "Null module object");
778 }
779 if (!java_lang_Module::is_instance(module())) {
780 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
781 "module is not an instance of type java.lang.Module");
782 }
783
784 // Ensure that this is an unnamed module
785 oop name = java_lang_Module::name(module());
786 if (name != nullptr) {
787 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
788 "boot loader's unnamed module's java.lang.Module has a name");
789 }
790
791 // Validate java_base's loader is the boot loader.
792 oop loader = java_lang_Module::loader(module());
793 if (loader != nullptr) {
794 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
795 "Class loader must be the boot class loader");
796 }
797
798 log_debug(module)("set_bootloader_unnamed_module(): recording unnamed module for boot loader");
799
800 // Set java.lang.Module for the boot loader's unnamed module
801 ClassLoaderData* boot_loader_data = ClassLoaderData::the_null_class_loader_data();
802 ModuleEntry* unnamed_module = boot_loader_data->unnamed_module();
803 assert(unnamed_module != nullptr, "boot loader's unnamed ModuleEntry not defined");
804 unnamed_module->set_module(boot_loader_data->add_handle(module));
805 // Store pointer to the ModuleEntry in the unnamed module's java.lang.Module object.
806 java_lang_Module::set_module_entry(module(), unnamed_module);
807 }
808
809 void Modules::add_module_exports(Handle from_module, jstring package_name, Handle to_module, TRAPS) {
810 check_cds_restrictions(CHECK);
811
812 if (package_name == nullptr) {
813 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
814 "package is null");
815 }
816 if (from_module.is_null()) {
817 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
818 "from_module is null");
819 }
820 ModuleEntry* from_module_entry = get_module_entry(from_module, CHECK);
821 if (from_module_entry == nullptr) {
822 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
823 "from_module cannot be found");
824 }
825
826 // All packages in unnamed and open modules are exported by default.
827 if (!from_module_entry->is_named() || from_module_entry->is_open()) return;
828
829 ModuleEntry* to_module_entry;
830 if (to_module.is_null()) {
831 to_module_entry = nullptr; // It's an unqualified export.
832 } else {
833 to_module_entry = get_module_entry(to_module, CHECK);
834 if (to_module_entry == nullptr) {
835 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
836 "to_module is invalid");
837 }
838 }
839
840 PackageEntry* package_entry = nullptr;
841 char buf[128];
842 int package_len;
843
844 ResourceMark rm(THREAD);
845 const char* pkg = as_internal_package(JNIHandles::resolve_non_null(package_name), buf, sizeof(buf), package_len);
846 {
847 MutexLocker ml(THREAD, Module_lock);
848 package_entry = get_locked_package_entry(from_module_entry, pkg, package_len);
849 // Do nothing if modules are the same
850 // If the package is not found we'll throw an exception later
851 if (from_module_entry != to_module_entry &&
852 package_entry != nullptr) {
853 package_entry->set_exported(to_module_entry);
854 }
855 }
856
857 // Handle errors and logging outside locked section
858 if (package_entry == nullptr) {
859 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
860 err_msg("Package %s not found in from_module %s",
861 pkg != nullptr ? pkg : "",
862 from_module_entry->name()->as_C_string()));
863 }
864
865 if (log_is_enabled(Debug, module)) {
866 log_debug(module)("add_module_exports(): package %s in module %s is exported to module %s",
867 package_entry->name()->as_C_string(),
868 from_module_entry->name()->as_C_string(),
869 to_module_entry == nullptr ? "null" :
870 to_module_entry->is_named() ?
871 to_module_entry->name()->as_C_string() : UNNAMED_MODULE);
872 }
873 }
874
875
876 void Modules::add_module_exports_qualified(Handle from_module, jstring package,
877 Handle to_module, TRAPS) {
878 check_cds_restrictions(CHECK);
879 if (to_module.is_null()) {
880 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
881 "to_module is null");
882 }
883 add_module_exports(from_module, package, to_module, CHECK);
884 }
885
886 void Modules::add_reads_module(Handle from_module, Handle to_module, TRAPS) {
887 check_cds_restrictions(CHECK);
888 if (from_module.is_null()) {
889 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
890 "from_module is null");
891 }
892
893 ModuleEntry* from_module_entry = get_module_entry(from_module, CHECK);
894 if (from_module_entry == nullptr) {
895 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
896 "from_module is not valid");
897 }
898
899 ModuleEntry* to_module_entry;
900 if (!to_module.is_null()) {
901 to_module_entry = get_module_entry(to_module, CHECK);
902 if (to_module_entry == nullptr) {
903 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
904 "to_module is invalid");
905 }
906 } else {
907 to_module_entry = nullptr;
908 }
909
910 ResourceMark rm(THREAD);
911 log_debug(module)("add_reads_module(): Adding read from module %s to module %s",
912 from_module_entry->is_named() ?
913 from_module_entry->name()->as_C_string() : UNNAMED_MODULE,
914 to_module_entry == nullptr ? "all unnamed" :
915 (to_module_entry->is_named() ?
916 to_module_entry->name()->as_C_string() : UNNAMED_MODULE));
917
918 // if modules are the same or if from_module is unnamed then no need to add the read.
919 if (from_module_entry != to_module_entry && from_module_entry->is_named()) {
920 from_module_entry->add_read(to_module_entry);
921 }
922 }
923
924 // This method is called by JFR and JNI.
925 jobject Modules::get_module(jclass clazz, TRAPS) {
926 assert(ModuleEntryTable::javabase_defined(),
927 "Attempt to call get_module before " JAVA_BASE_NAME " is defined");
928
929 if (clazz == nullptr) {
930 THROW_MSG_(vmSymbols::java_lang_NullPointerException(),
931 "class is null", nullptr);
932 }
933 oop mirror = JNIHandles::resolve_non_null(clazz);
934 if (mirror == nullptr) {
935 log_debug(module)("get_module(): no mirror, returning nullptr");
936 return nullptr;
937 }
938 if (!java_lang_Class::is_instance(mirror)) {
939 THROW_MSG_(vmSymbols::java_lang_IllegalArgumentException(),
940 "Invalid class", nullptr);
941 }
942
943 oop module = java_lang_Class::module(mirror);
944
945 assert(module != nullptr, "java.lang.Class module field not set");
946 assert(java_lang_Module::is_instance(module), "module is not an instance of type java.lang.Module");
947
948 LogTarget(Debug,module) lt;
949 if (lt.is_enabled()) {
950 ResourceMark rm(THREAD);
951 LogStream ls(lt);
952 Klass* klass = java_lang_Class::as_Klass(mirror);
953 oop module_name = java_lang_Module::name(module);
954 if (module_name != nullptr) {
955 ls.print("get_module(): module ");
956 java_lang_String::print(module_name, tty);
957 } else {
958 ls.print("get_module(): Unnamed Module");
959 }
960 if (klass != nullptr) {
961 ls.print_cr(" for class %s", klass->external_name());
962 } else {
963 ls.print_cr(" for primitive class");
964 }
965 }
966
967 return JNIHandles::make_local(THREAD, module);
968 }
969
970 oop Modules::get_named_module(Handle h_loader, const char* package_name) {
971 assert(ModuleEntryTable::javabase_defined(),
972 "Attempt to call get_named_module before " JAVA_BASE_NAME " is defined");
973 assert(h_loader.is_null() || java_lang_ClassLoader::is_subclass(h_loader->klass()),
974 "Class loader is not a subclass of java.lang.ClassLoader");
975 assert(package_name != nullptr, "the package_name should not be null");
976
977 if (strlen(package_name) == 0) {
978 return nullptr;
979 }
980 TempNewSymbol package_sym = SymbolTable::new_symbol(package_name);
981 const PackageEntry* const pkg_entry =
982 get_package_entry_by_name(package_sym, h_loader);
983 const ModuleEntry* const module_entry = (pkg_entry != nullptr ? pkg_entry->module() : nullptr);
984
985 if (module_entry != nullptr && module_entry->module() != nullptr && module_entry->is_named()) {
986 return module_entry->module();
987 }
988 return nullptr;
989 }
990
991 // Export package in module to all unnamed modules.
992 void Modules::add_module_exports_to_all_unnamed(Handle module, jstring package_name, TRAPS) {
993 check_cds_restrictions(CHECK);
994 if (module.is_null()) {
995 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
996 "module is null");
997 }
998 if (package_name == nullptr) {
999 THROW_MSG(vmSymbols::java_lang_NullPointerException(),
1000 "package is null");
1001 }
1002 ModuleEntry* module_entry = get_module_entry(module, CHECK);
1003 if (module_entry == nullptr) {
1004 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
1005 "module is invalid");
1006 }
1007
1008 // No-op for unnamed module and open modules
1009 if (!module_entry->is_named() || module_entry->is_open())
1010 return;
1011
1012 ResourceMark rm(THREAD);
1013 char buf[128];
1014 int pkg_len;
1015 const char* pkg = as_internal_package(JNIHandles::resolve_non_null(package_name), buf, sizeof(buf), pkg_len);
1016 PackageEntry* package_entry = nullptr;
1017 {
1018 MutexLocker m1(THREAD, Module_lock);
1019 package_entry = get_locked_package_entry(module_entry, pkg, pkg_len);
1020
1021 // Mark package as exported to all unnamed modules.
1022 if (package_entry != nullptr) {
1023 package_entry->set_is_exported_allUnnamed();
1024 }
1025 }
1026
1027 // Handle errors and logging outside locked section
1028 if (package_entry == nullptr) {
1029 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
1030 err_msg("Package %s not found in module %s",
1031 pkg != nullptr ? pkg : "",
1032 module_entry->name()->as_C_string()));
1033 }
1034
1035 if (log_is_enabled(Debug, module)) {
1036 log_debug(module)("add_module_exports_to_all_unnamed(): package %s in module"
1037 " %s is exported to all unnamed modules",
1038 package_entry->name()->as_C_string(),
1039 module_entry->name()->as_C_string());
1040 }
1041 }