1 /*
2 * Copyright (c) 1997, 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/cds_globals.hpp"
27 #include "cds/cdsConfig.hpp"
28 #include "cds/filemap.hpp"
29 #include "classfile/classFileStream.hpp"
30 #include "classfile/classLoader.inline.hpp"
31 #include "classfile/classLoaderData.inline.hpp"
32 #include "classfile/classLoaderExt.hpp"
33 #include "classfile/classLoadInfo.hpp"
34 #include "classfile/javaClasses.hpp"
35 #include "classfile/moduleEntry.hpp"
36 #include "classfile/modules.hpp"
37 #include "classfile/packageEntry.hpp"
38 #include "classfile/klassFactory.hpp"
39 #include "classfile/symbolTable.hpp"
40 #include "classfile/systemDictionary.hpp"
41 #include "classfile/systemDictionaryShared.hpp"
42 #include "classfile/vmClasses.hpp"
43 #include "classfile/vmSymbols.hpp"
44 #include "compiler/compileBroker.hpp"
45 #include "interpreter/bytecodeStream.hpp"
46 #include "interpreter/oopMapCache.hpp"
47 #include "jimage.hpp"
48 #include "jvm.h"
49 #include "logging/log.hpp"
50 #include "logging/logStream.hpp"
51 #include "logging/logTag.hpp"
52 #include "memory/allocation.inline.hpp"
53 #include "memory/oopFactory.hpp"
54 #include "memory/resourceArea.hpp"
55 #include "memory/universe.hpp"
56 #include "oops/instanceKlass.hpp"
57 #include "oops/instanceRefKlass.hpp"
58 #include "oops/klass.inline.hpp"
59 #include "oops/method.inline.hpp"
60 #include "oops/objArrayOop.inline.hpp"
61 #include "oops/oop.inline.hpp"
62 #include "oops/symbol.hpp"
63 #include "prims/jvm_misc.hpp"
64 #include "runtime/arguments.hpp"
65 #include "runtime/handles.inline.hpp"
66 #include "runtime/init.hpp"
67 #include "runtime/interfaceSupport.inline.hpp"
68 #include "runtime/java.hpp"
69 #include "runtime/javaCalls.hpp"
70 #include "runtime/os.hpp"
71 #include "runtime/perfData.hpp"
72 #include "runtime/threadCritical.hpp"
73 #include "runtime/timer.hpp"
74 #include "runtime/vm_version.hpp"
75 #include "services/management.hpp"
76 #include "services/threadService.hpp"
77 #include "utilities/checkedCast.hpp"
78 #include "utilities/classpathStream.hpp"
79 #include "utilities/events.hpp"
80 #include "utilities/macros.hpp"
81 #include "utilities/utf8.hpp"
82
83 // Entry point in java.dll for path canonicalization
84
85 typedef int (*canonicalize_fn_t)(const char *orig, char *out, int len);
86
87 static canonicalize_fn_t CanonicalizeEntry = nullptr;
88
89 // Entry points for jimage.dll for loading jimage file entries
90
91 static JImageOpen_t JImageOpen = nullptr;
92 static JImageClose_t JImageClose = nullptr;
93 static JImageFindResource_t JImageFindResource = nullptr;
94 static JImageGetResource_t JImageGetResource = nullptr;
95
96 // JimageFile pointer, or null if exploded JDK build.
97 static JImageFile* JImage_file = nullptr;
98
99 // Globals
100
101 PerfCounter* ClassLoader::_perf_accumulated_time = nullptr;
102 PerfCounter* ClassLoader::_perf_classes_inited = nullptr;
103 PerfCounter* ClassLoader::_perf_class_init_time = nullptr;
104 PerfCounter* ClassLoader::_perf_class_init_selftime = nullptr;
105 PerfCounter* ClassLoader::_perf_classes_verified = nullptr;
106 PerfCounter* ClassLoader::_perf_class_verify_time = nullptr;
107 PerfCounter* ClassLoader::_perf_class_verify_selftime = nullptr;
108 PerfCounter* ClassLoader::_perf_classes_linked = nullptr;
109 PerfCounter* ClassLoader::_perf_class_link_time = nullptr;
110 PerfCounter* ClassLoader::_perf_class_link_selftime = nullptr;
111 PerfCounter* ClassLoader::_perf_shared_classload_time = nullptr;
112 PerfCounter* ClassLoader::_perf_sys_classload_time = nullptr;
113 PerfCounter* ClassLoader::_perf_app_classload_time = nullptr;
114 PerfCounter* ClassLoader::_perf_app_classload_selftime = nullptr;
115 PerfCounter* ClassLoader::_perf_app_classload_count = nullptr;
116 PerfCounter* ClassLoader::_perf_define_appclasses = nullptr;
117 PerfCounter* ClassLoader::_perf_define_appclass_time = nullptr;
118 PerfCounter* ClassLoader::_perf_define_appclass_selftime = nullptr;
119 PerfCounter* ClassLoader::_perf_app_classfile_bytes_read = nullptr;
120 PerfCounter* ClassLoader::_perf_sys_classfile_bytes_read = nullptr;
121 PerfCounter* ClassLoader::_unsafe_defineClassCallCounter = nullptr;
122
123 GrowableArray<ModuleClassPathList*>* ClassLoader::_patch_mod_entries = nullptr;
124 GrowableArray<ModuleClassPathList*>* ClassLoader::_exploded_entries = nullptr;
125 ClassPathEntry* ClassLoader::_jrt_entry = nullptr;
126
127 ClassPathEntry* volatile ClassLoader::_first_append_entry_list = nullptr;
128 ClassPathEntry* volatile ClassLoader::_last_append_entry = nullptr;
129 #if INCLUDE_CDS
130 ClassPathEntry* ClassLoader::_app_classpath_entries = nullptr;
131 ClassPathEntry* ClassLoader::_last_app_classpath_entry = nullptr;
132 ClassPathEntry* ClassLoader::_module_path_entries = nullptr;
133 ClassPathEntry* ClassLoader::_last_module_path_entry = nullptr;
134 #endif
135
136 // helper routines
137 bool string_starts_with(const char* str, const char* str_to_find) {
138 size_t str_len = strlen(str);
139 size_t str_to_find_len = strlen(str_to_find);
140 if (str_to_find_len > str_len) {
141 return false;
142 }
143 return (strncmp(str, str_to_find, str_to_find_len) == 0);
144 }
145
146 static const char* get_jimage_version_string() {
147 static char version_string[10] = "";
148 if (version_string[0] == '\0') {
149 jio_snprintf(version_string, sizeof(version_string), "%d.%d",
150 VM_Version::vm_major_version(), VM_Version::vm_minor_version());
151 }
152 return (const char*)version_string;
153 }
154
155 bool ClassLoader::string_ends_with(const char* str, const char* str_to_find) {
156 size_t str_len = strlen(str);
157 size_t str_to_find_len = strlen(str_to_find);
158 if (str_to_find_len > str_len) {
159 return false;
160 }
161 return (strncmp(str + (str_len - str_to_find_len), str_to_find, str_to_find_len) == 0);
162 }
163
164 // Used to obtain the package name from a fully qualified class name.
165 Symbol* ClassLoader::package_from_class_name(const Symbol* name, bool* bad_class_name) {
166 if (name == nullptr) {
167 if (bad_class_name != nullptr) {
168 *bad_class_name = true;
169 }
170 return nullptr;
171 }
172
173 int utf_len = name->utf8_length();
174 const jbyte* base = (const jbyte*)name->base();
175 const jbyte* start = base;
176 const jbyte* end = UTF8::strrchr(start, utf_len, JVM_SIGNATURE_SLASH);
177 if (end == nullptr) {
178 return nullptr;
179 }
180 // Skip over '['s
181 if (*start == JVM_SIGNATURE_ARRAY) {
182 do {
183 start++;
184 } while (start < end && *start == JVM_SIGNATURE_ARRAY);
185
186 // Fully qualified class names should not contain a 'L'.
187 // Set bad_class_name to true to indicate that the package name
188 // could not be obtained due to an error condition.
189 // In this situation, is_same_class_package returns false.
190 if (*start == JVM_SIGNATURE_CLASS) {
191 if (bad_class_name != nullptr) {
192 *bad_class_name = true;
193 }
194 return nullptr;
195 }
196 }
197 // A class name could have just the slash character in the name,
198 // in which case start > end
199 if (start >= end) {
200 // No package name
201 if (bad_class_name != nullptr) {
202 *bad_class_name = true;
203 }
204 return nullptr;
205 }
206 return SymbolTable::new_symbol(name, pointer_delta_as_int(start, base), pointer_delta_as_int(end, base));
207 }
208
209 // Given a fully qualified package name, find its defining package in the class loader's
210 // package entry table.
211 PackageEntry* ClassLoader::get_package_entry(Symbol* pkg_name, ClassLoaderData* loader_data) {
212 if (pkg_name == nullptr) {
213 return nullptr;
214 }
215 PackageEntryTable* pkgEntryTable = loader_data->packages();
216 return pkgEntryTable->lookup_only(pkg_name);
217 }
218
219 const char* ClassPathEntry::copy_path(const char* path) {
220 char* copy = NEW_C_HEAP_ARRAY(char, strlen(path)+1, mtClass);
221 strcpy(copy, path);
222 return copy;
223 }
224
225 ClassPathDirEntry::~ClassPathDirEntry() {
226 FREE_C_HEAP_ARRAY(char, _dir);
227 }
228
229 ClassFileStream* ClassPathDirEntry::open_stream(JavaThread* current, const char* name) {
230 // construct full path name
231 assert((_dir != nullptr) && (name != nullptr), "sanity");
232 size_t path_len = strlen(_dir) + strlen(name) + strlen(os::file_separator()) + 1;
233 char* path = NEW_RESOURCE_ARRAY_IN_THREAD(current, char, path_len);
234 int len = jio_snprintf(path, path_len, "%s%s%s", _dir, os::file_separator(), name);
235 assert(len == (int)(path_len - 1), "sanity");
236 // check if file exists
237 struct stat st;
238 if (os::stat(path, &st) == 0) {
239 // found file, open it
240 int file_handle = os::open(path, 0, 0);
241 if (file_handle != -1) {
242 // read contents into resource array
243 u1* buffer = NEW_RESOURCE_ARRAY_IN_THREAD(current, u1, st.st_size);
244 size_t num_read = ::read(file_handle, (char*) buffer, st.st_size);
245 // close file
246 ::close(file_handle);
247 // construct ClassFileStream
248 if (num_read == (size_t)st.st_size) {
249 if (UsePerfData) {
250 ClassLoader::perf_sys_classfile_bytes_read()->inc(num_read);
251 }
252 #ifdef ASSERT
253 // Freeing path is a no-op here as buffer prevents it from being reclaimed. But we keep it for
254 // debug builds so that we guard against use-after-free bugs.
255 FREE_RESOURCE_ARRAY_IN_THREAD(current, char, path, path_len);
256 #endif
257 // We don't verify the length of the classfile stream fits in an int, but this is the
258 // bootloader so we have control of this.
259 // Resource allocated
260 return new ClassFileStream(buffer,
261 checked_cast<int>(st.st_size),
262 _dir,
263 ClassFileStream::verify);
264 }
265 }
266 }
267 FREE_RESOURCE_ARRAY_IN_THREAD(current, char, path, path_len);
268 return nullptr;
269 }
270
271 ClassPathZipEntry::ClassPathZipEntry(jzfile* zip, const char* zip_name,
272 bool is_boot_append, bool from_class_path_attr) : ClassPathEntry() {
273 _zip = zip;
274 _zip_name = copy_path(zip_name);
275 _from_class_path_attr = from_class_path_attr;
276 }
277
278 ClassPathZipEntry::~ClassPathZipEntry() {
279 ZipLibrary::close(_zip);
280 FREE_C_HEAP_ARRAY(char, _zip_name);
281 }
282
283 u1* ClassPathZipEntry::open_entry(JavaThread* current, const char* name, jint* filesize, bool nul_terminate) {
284 // enable call to C land
285 ThreadToNativeFromVM ttn(current);
286 // check whether zip archive contains name
287 jint name_len;
288 jzentry* entry = ZipLibrary::find_entry(_zip, name, filesize, &name_len);
289 if (entry == nullptr) return nullptr;
290 u1* buffer;
291 char name_buf[128];
292 char* filename;
293 if (name_len < 128) {
294 filename = name_buf;
295 } else {
296 filename = NEW_RESOURCE_ARRAY(char, name_len + 1);
297 }
298
299 // read contents into resource array
300 size_t size = (uint32_t)(*filesize);
301 if (nul_terminate) {
302 if (sizeof(size) == sizeof(uint32_t) && size == UINT_MAX) {
303 return nullptr; // 32-bit integer overflow will occur.
304 }
305 size++;
306 }
307 buffer = NEW_RESOURCE_ARRAY(u1, size);
308 if (!ZipLibrary::read_entry(_zip, entry, buffer, filename)) {
309 return nullptr;
310 }
311
312 // return result
313 if (nul_terminate) {
314 buffer[size - 1] = 0;
315 }
316 return buffer;
317 }
318
319 ClassFileStream* ClassPathZipEntry::open_stream(JavaThread* current, const char* name) {
320 jint filesize;
321 u1* buffer = open_entry(current, name, &filesize, false);
322 if (buffer == nullptr) {
323 return nullptr;
324 }
325 if (UsePerfData) {
326 ClassLoader::perf_sys_classfile_bytes_read()->inc(filesize);
327 }
328 // Resource allocated
329 return new ClassFileStream(buffer,
330 filesize,
331 _zip_name,
332 ClassFileStream::verify);
333 }
334
335 DEBUG_ONLY(ClassPathImageEntry* ClassPathImageEntry::_singleton = nullptr;)
336
337 JImageFile* ClassPathImageEntry::jimage() const {
338 return JImage_file;
339 }
340
341 JImageFile* ClassPathImageEntry::jimage_non_null() const {
342 assert(ClassLoader::has_jrt_entry(), "must be");
343 assert(jimage() != nullptr, "should have been opened by ClassLoader::lookup_vm_options "
344 "and remained throughout normal JVM lifetime");
345 return jimage();
346 }
347
348 void ClassPathImageEntry::close_jimage() {
349 if (jimage() != nullptr) {
350 (*JImageClose)(jimage());
351 JImage_file = nullptr;
352 }
353 }
354
355 ClassPathImageEntry::ClassPathImageEntry(JImageFile* jimage, const char* name) :
356 ClassPathEntry() {
357 guarantee(jimage != nullptr, "jimage file is null");
358 guarantee(name != nullptr, "jimage file name is null");
359 assert(_singleton == nullptr, "VM supports only one jimage");
360 DEBUG_ONLY(_singleton = this);
361 size_t len = strlen(name) + 1;
362 _name = copy_path(name);
363 }
364
365 ClassFileStream* ClassPathImageEntry::open_stream(JavaThread* current, const char* name) {
366 return open_stream_for_loader(current, name, ClassLoaderData::the_null_class_loader_data());
367 }
368
369 // For a class in a named module, look it up in the jimage file using this syntax:
370 // /<module-name>/<package-name>/<base-class>
371 //
372 // Assumptions:
373 // 1. There are no unnamed modules in the jimage file.
374 // 2. A package is in at most one module in the jimage file.
375 //
376 ClassFileStream* ClassPathImageEntry::open_stream_for_loader(JavaThread* current, const char* name, ClassLoaderData* loader_data) {
377 jlong size;
378 JImageLocationRef location = (*JImageFindResource)(jimage_non_null(), "", get_jimage_version_string(), name, &size);
379
380 if (location == 0) {
381 TempNewSymbol class_name = SymbolTable::new_symbol(name);
382 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
383
384 if (pkg_name != nullptr) {
385 if (!Universe::is_module_initialized()) {
386 location = (*JImageFindResource)(jimage_non_null(), JAVA_BASE_NAME, get_jimage_version_string(), name, &size);
387 } else {
388 PackageEntry* package_entry = ClassLoader::get_package_entry(pkg_name, loader_data);
389 if (package_entry != nullptr) {
390 ResourceMark rm(current);
391 // Get the module name
392 ModuleEntry* module = package_entry->module();
393 assert(module != nullptr, "Boot classLoader package missing module");
394 assert(module->is_named(), "Boot classLoader package is in unnamed module");
395 const char* module_name = module->name()->as_C_string();
396 if (module_name != nullptr) {
397 location = (*JImageFindResource)(jimage_non_null(), module_name, get_jimage_version_string(), name, &size);
398 }
399 }
400 }
401 }
402 }
403 if (location != 0) {
404 if (UsePerfData) {
405 ClassLoader::perf_sys_classfile_bytes_read()->inc(size);
406 }
407 char* data = NEW_RESOURCE_ARRAY(char, size);
408 (*JImageGetResource)(jimage_non_null(), location, data, size);
409 // Resource allocated
410 assert(this == (ClassPathImageEntry*)ClassLoader::get_jrt_entry(), "must be");
411 return new ClassFileStream((u1*)data,
412 checked_cast<int>(size),
413 _name,
414 ClassFileStream::verify,
415 true); // from_boot_loader_modules_image
416 }
417
418 return nullptr;
419 }
420
421 JImageLocationRef ClassLoader::jimage_find_resource(JImageFile* jf,
422 const char* module_name,
423 const char* file_name,
424 jlong &size) {
425 return ((*JImageFindResource)(jf, module_name, get_jimage_version_string(), file_name, &size));
426 }
427
428 bool ClassPathImageEntry::is_modules_image() const {
429 assert(this == _singleton, "VM supports a single jimage");
430 assert(this == (ClassPathImageEntry*)ClassLoader::get_jrt_entry(), "must be used for jrt entry");
431 return true;
432 }
433
434 #if INCLUDE_CDS
435 void ClassLoader::exit_with_path_failure(const char* error, const char* message) {
436 assert(CDSConfig::is_dumping_archive(), "sanity");
437 tty->print_cr("Hint: enable -Xlog:class+path=info to diagnose the failure");
438 vm_exit_during_initialization(error, message);
439 }
440 #endif
441
442 ModuleClassPathList::ModuleClassPathList(Symbol* module_name) {
443 _module_name = module_name;
444 _module_first_entry = nullptr;
445 _module_last_entry = nullptr;
446 }
447
448 ModuleClassPathList::~ModuleClassPathList() {
449 // Clean out each ClassPathEntry on list
450 ClassPathEntry* e = _module_first_entry;
451 while (e != nullptr) {
452 ClassPathEntry* next_entry = e->next();
453 delete e;
454 e = next_entry;
455 }
456 }
457
458 void ModuleClassPathList::add_to_list(ClassPathEntry* new_entry) {
459 if (new_entry != nullptr) {
460 if (_module_last_entry == nullptr) {
461 _module_first_entry = _module_last_entry = new_entry;
462 } else {
463 _module_last_entry->set_next(new_entry);
464 _module_last_entry = new_entry;
465 }
466 }
467 }
468
469 void ClassLoader::trace_class_path(const char* msg, const char* name) {
470 LogTarget(Info, class, path) lt;
471 if (lt.is_enabled()) {
472 LogStream ls(lt);
473 if (msg) {
474 ls.print("%s", msg);
475 }
476 if (name) {
477 if (strlen(name) < 256) {
478 ls.print("%s", name);
479 } else {
480 // For very long paths, we need to print each character separately,
481 // as print_cr() has a length limit
482 while (name[0] != '\0') {
483 ls.print("%c", name[0]);
484 name++;
485 }
486 }
487 }
488 ls.cr();
489 }
490 }
491
492 void ClassLoader::setup_bootstrap_search_path(JavaThread* current) {
493 const char* bootcp = Arguments::get_boot_class_path();
494 assert(bootcp != nullptr, "Boot class path must not be nullptr");
495 if (PrintSharedArchiveAndExit) {
496 // Don't print bootcp - this is the bootcp of this current VM process, not necessarily
497 // the same as the boot classpath of the shared archive.
498 } else {
499 trace_class_path("bootstrap loader class path=", bootcp);
500 }
501 setup_bootstrap_search_path_impl(current, bootcp);
502 }
503
504 #if INCLUDE_CDS
505 void ClassLoader::setup_app_search_path(JavaThread* current, const char *class_path) {
506 assert(CDSConfig::is_dumping_archive(), "sanity");
507
508 ResourceMark rm(current);
509 ClasspathStream cp_stream(class_path);
510
511 while (cp_stream.has_next()) {
512 const char* path = cp_stream.get_next();
513 update_class_path_entry_list(current, path, /* check_for_duplicates */ true,
514 /* is_boot_append */ false, /* from_class_path_attr */ false);
515 }
516 }
517
518 void ClassLoader::add_to_module_path_entries(const char* path,
519 ClassPathEntry* entry) {
520 assert(entry != nullptr, "ClassPathEntry should not be nullptr");
521 assert(CDSConfig::is_dumping_archive(), "sanity");
522
523 // The entry does not exist, add to the list
524 if (_module_path_entries == nullptr) {
525 assert(_last_module_path_entry == nullptr, "Sanity");
526 _module_path_entries = _last_module_path_entry = entry;
527 } else {
528 _last_module_path_entry->set_next(entry);
529 _last_module_path_entry = entry;
530 }
531 }
532
533 // Add a module path to the _module_path_entries list.
534 void ClassLoader::setup_module_search_path(JavaThread* current, const char* path) {
535 assert(CDSConfig::is_dumping_archive(), "sanity");
536 struct stat st;
537 if (os::stat(path, &st) != 0) {
538 tty->print_cr("os::stat error %d (%s). CDS dump aborted (path was \"%s\").",
539 errno, os::errno_name(errno), path);
540 vm_exit_during_initialization();
541 }
542 // File or directory found
543 ClassPathEntry* new_entry = nullptr;
544 new_entry = create_class_path_entry(current, path, &st,
545 false /*is_boot_append */, false /* from_class_path_attr */);
546 if (new_entry != nullptr) {
547 add_to_module_path_entries(path, new_entry);
548 }
549 }
550
551 #endif // INCLUDE_CDS
552
553 void ClassLoader::close_jrt_image() {
554 // Not applicable for exploded builds
555 if (!ClassLoader::has_jrt_entry()) return;
556 _jrt_entry->close_jimage();
557 }
558
559 // Construct the array of module/path pairs as specified to --patch-module
560 // for the boot loader to search ahead of the jimage, if the class being
561 // loaded is defined to a module that has been specified to --patch-module.
562 void ClassLoader::setup_patch_mod_entries() {
563 JavaThread* current = JavaThread::current();
564 GrowableArray<ModulePatchPath*>* patch_mod_args = Arguments::get_patch_mod_prefix();
565 int num_of_entries = patch_mod_args->length();
566
567 // Set up the boot loader's _patch_mod_entries list
568 _patch_mod_entries = new (mtModule) GrowableArray<ModuleClassPathList*>(num_of_entries, mtModule);
569
570 for (int i = 0; i < num_of_entries; i++) {
571 const char* module_name = (patch_mod_args->at(i))->module_name();
572 Symbol* const module_sym = SymbolTable::new_symbol(module_name);
573 assert(module_sym != nullptr, "Failed to obtain Symbol for module name");
574 ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
575
576 char* class_path = (patch_mod_args->at(i))->path_string();
577 ResourceMark rm(current);
578 ClasspathStream cp_stream(class_path);
579
580 while (cp_stream.has_next()) {
581 const char* path = cp_stream.get_next();
582 struct stat st;
583 if (os::stat(path, &st) == 0) {
584 // File or directory found
585 ClassPathEntry* new_entry = create_class_path_entry(current, path, &st, false, false);
586 // If the path specification is valid, enter it into this module's list
587 if (new_entry != nullptr) {
588 module_cpl->add_to_list(new_entry);
589 }
590 }
591 }
592
593 // Record the module into the list of --patch-module entries only if
594 // valid ClassPathEntrys have been created
595 if (module_cpl->module_first_entry() != nullptr) {
596 _patch_mod_entries->push(module_cpl);
597 }
598 }
599 }
600
601 // Determine whether the module has been patched via the command-line
602 // option --patch-module
603 bool ClassLoader::is_in_patch_mod_entries(Symbol* module_name) {
604 if (_patch_mod_entries != nullptr && _patch_mod_entries->is_nonempty()) {
605 int table_len = _patch_mod_entries->length();
606 for (int i = 0; i < table_len; i++) {
607 ModuleClassPathList* patch_mod = _patch_mod_entries->at(i);
608 if (module_name->fast_compare(patch_mod->module_name()) == 0) {
609 return true;
610 }
611 }
612 }
613 return false;
614 }
615
616 // Set up the _jrt_entry if present and boot append path
617 void ClassLoader::setup_bootstrap_search_path_impl(JavaThread* current, const char *class_path) {
618 ResourceMark rm(current);
619 ClasspathStream cp_stream(class_path);
620 bool set_base_piece = true;
621
622 #if INCLUDE_CDS
623 if (CDSConfig::is_dumping_archive()) {
624 if (!Arguments::has_jimage()) {
625 vm_exit_during_initialization("CDS is not supported in exploded JDK build", nullptr);
626 }
627 }
628 #endif
629
630 while (cp_stream.has_next()) {
631 const char* path = cp_stream.get_next();
632
633 if (set_base_piece) {
634 // The first time through the bootstrap_search setup, it must be determined
635 // what the base or core piece of the boot loader search is. Either a java runtime
636 // image is present or this is an exploded module build situation.
637 assert(string_ends_with(path, MODULES_IMAGE_NAME) || string_ends_with(path, JAVA_BASE_NAME),
638 "Incorrect boot loader search path, no java runtime image or " JAVA_BASE_NAME " exploded build");
639 struct stat st;
640 if (os::stat(path, &st) == 0) {
641 // Directory found
642 if (JImage_file != nullptr) {
643 assert(Arguments::has_jimage(), "sanity check");
644 const char* canonical_path = get_canonical_path(path, current);
645 assert(canonical_path != nullptr, "canonical_path issue");
646
647 _jrt_entry = new ClassPathImageEntry(JImage_file, canonical_path);
648 assert(_jrt_entry != nullptr && _jrt_entry->is_modules_image(), "No java runtime image present");
649 assert(_jrt_entry->jimage() != nullptr, "No java runtime image");
650 } // else it's an exploded build.
651 } else {
652 // If path does not exist, exit
653 vm_exit_during_initialization("Unable to establish the boot loader search path", path);
654 }
655 set_base_piece = false;
656 } else {
657 // Every entry on the boot class path after the initial base piece,
658 // which is set by os::set_boot_path(), is considered an appended entry.
659 update_class_path_entry_list(current, path, /* check_for_duplicates */ false,
660 /* is_boot_append */ true, /* from_class_path_attr */ false);
661 }
662 }
663 }
664
665 // Gets the exploded path for the named module. The memory for the path
666 // is allocated on the C heap if `c_heap` is true otherwise in the resource area.
667 static const char* get_exploded_module_path(const char* module_name, bool c_heap) {
668 const char *home = Arguments::get_java_home();
669 const char file_sep = os::file_separator()[0];
670 // 10 represents the length of "modules" + 2 file separators + \0
671 size_t len = strlen(home) + strlen(module_name) + 10;
672 char *path = c_heap ? NEW_C_HEAP_ARRAY(char, len, mtModule) : NEW_RESOURCE_ARRAY(char, len);
673 jio_snprintf(path, len, "%s%cmodules%c%s", home, file_sep, file_sep, module_name);
674 return path;
675 }
676
677 // During an exploded modules build, each module defined to the boot loader
678 // will be added to the ClassLoader::_exploded_entries array.
679 void ClassLoader::add_to_exploded_build_list(JavaThread* current, Symbol* module_sym) {
680 assert(!ClassLoader::has_jrt_entry(), "Exploded build not applicable");
681 assert(_exploded_entries != nullptr, "_exploded_entries was not initialized");
682
683 // Find the module's symbol
684 ResourceMark rm(current);
685 const char *module_name = module_sym->as_C_string();
686 const char *path = get_exploded_module_path(module_name, false);
687
688 struct stat st;
689 if (os::stat(path, &st) == 0) {
690 // Directory found
691 ClassPathEntry* new_entry = create_class_path_entry(current, path, &st, false, false);
692
693 // If the path specification is valid, enter it into this module's list.
694 // There is no need to check for duplicate modules in the exploded entry list,
695 // since no two modules with the same name can be defined to the boot loader.
696 // This is checked at module definition time in Modules::define_module.
697 if (new_entry != nullptr) {
698 ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
699 module_cpl->add_to_list(new_entry);
700 {
701 MutexLocker ml(current, Module_lock);
702 _exploded_entries->push(module_cpl);
703 }
704 log_info(class, load)("path: %s", path);
705 }
706 }
707 }
708
709 jzfile* ClassLoader::open_zip_file(const char* canonical_path, char** error_msg, JavaThread* thread) {
710 // enable call to C land
711 ThreadToNativeFromVM ttn(thread);
712 HandleMark hm(thread);
713 return ZipLibrary::open(canonical_path, error_msg);
714 }
715
716 ClassPathEntry* ClassLoader::create_class_path_entry(JavaThread* current,
717 const char *path, const struct stat* st,
718 bool is_boot_append,
719 bool from_class_path_attr) {
720 ClassPathEntry* new_entry = nullptr;
721 if ((st->st_mode & S_IFMT) == S_IFREG) {
722 ResourceMark rm(current);
723 // Regular file, should be a zip file
724 // Canonicalized filename
725 const char* canonical_path = get_canonical_path(path, current);
726 if (canonical_path == nullptr) {
727 return nullptr;
728 }
729 char* error_msg = nullptr;
730 jzfile* zip = open_zip_file(canonical_path, &error_msg, current);
731 if (zip != nullptr && error_msg == nullptr) {
732 new_entry = new ClassPathZipEntry(zip, path, is_boot_append, from_class_path_attr);
733 } else {
734 #if INCLUDE_CDS
735 ClassLoaderExt::set_has_non_jar_in_classpath();
736 #endif
737 return nullptr;
738 }
739 log_info(class, path)("opened: %s", path);
740 log_info(class, load)("opened: %s", path);
741 } else {
742 // Directory
743 new_entry = new ClassPathDirEntry(path);
744 log_info(class, load)("path: %s", path);
745 }
746 return new_entry;
747 }
748
749
750 // Create a class path zip entry for a given path (return null if not found
751 // or zip/JAR file cannot be opened)
752 ClassPathZipEntry* ClassLoader::create_class_path_zip_entry(const char *path, bool is_boot_append) {
753 // check for a regular file
754 struct stat st;
755 if (os::stat(path, &st) == 0) {
756 if ((st.st_mode & S_IFMT) == S_IFREG) {
757 JavaThread* thread = JavaThread::current();
758 ResourceMark rm(thread);
759 const char* canonical_path = get_canonical_path(path, thread);
760 if (canonical_path != nullptr) {
761 char* error_msg = nullptr;
762 jzfile* zip = open_zip_file(canonical_path, &error_msg, thread);
763 if (zip != nullptr && error_msg == nullptr) {
764 // create using canonical path
765 return new ClassPathZipEntry(zip, canonical_path, is_boot_append, false);
766 }
767 }
768 }
769 }
770 return nullptr;
771 }
772
773 // The boot append entries are added with a lock, and read lock free.
774 void ClassLoader::add_to_boot_append_entries(ClassPathEntry *new_entry) {
775 if (new_entry != nullptr) {
776 MutexLocker ml(Bootclasspath_lock, Mutex::_no_safepoint_check_flag);
777 if (_last_append_entry == nullptr) {
778 _last_append_entry = new_entry;
779 assert(first_append_entry() == nullptr, "boot loader's append class path entry list not empty");
780 Atomic::release_store(&_first_append_entry_list, new_entry);
781 } else {
782 _last_append_entry->set_next(new_entry);
783 _last_append_entry = new_entry;
784 }
785 }
786 }
787
788 // Record the path entries specified in -cp during dump time. The recorded
789 // information will be used at runtime for loading the archived app classes.
790 //
791 // Note that at dump time, ClassLoader::_app_classpath_entries are NOT used for
792 // loading app classes. Instead, the app class are loaded by the
793 // jdk/internal/loader/ClassLoaders$AppClassLoader instance.
794 bool ClassLoader::add_to_app_classpath_entries(JavaThread* current,
795 ClassPathEntry* entry,
796 bool check_for_duplicates) {
797 #if INCLUDE_CDS
798 assert(entry != nullptr, "ClassPathEntry should not be nullptr");
799 ClassPathEntry* e = _app_classpath_entries;
800 if (check_for_duplicates) {
801 while (e != nullptr) {
802 if (strcmp(e->name(), entry->name()) == 0) {
803 // entry already exists
804 return false;
805 }
806 e = e->next();
807 }
808 }
809
810 // The entry does not exist, add to the list
811 if (_app_classpath_entries == nullptr) {
812 assert(_last_app_classpath_entry == nullptr, "Sanity");
813 _app_classpath_entries = _last_app_classpath_entry = entry;
814 } else {
815 _last_app_classpath_entry->set_next(entry);
816 _last_app_classpath_entry = entry;
817 }
818
819 if (entry->is_jar_file()) {
820 ClassLoaderExt::process_jar_manifest(current, entry);
821 }
822 #endif
823 return true;
824 }
825
826 // Returns true IFF the file/dir exists and the entry was successfully created.
827 bool ClassLoader::update_class_path_entry_list(JavaThread* current,
828 const char *path,
829 bool check_for_duplicates,
830 bool is_boot_append,
831 bool from_class_path_attr) {
832 struct stat st;
833 if (os::stat(path, &st) == 0) {
834 // File or directory found
835 ClassPathEntry* new_entry = nullptr;
836 new_entry = create_class_path_entry(current, path, &st, is_boot_append, from_class_path_attr);
837 if (new_entry == nullptr) {
838 return false;
839 }
840
841 // Do not reorder the bootclasspath which would break get_system_package().
842 // Add new entry to linked list
843 if (is_boot_append) {
844 add_to_boot_append_entries(new_entry);
845 } else {
846 if (!add_to_app_classpath_entries(current, new_entry, check_for_duplicates)) {
847 // new_entry is not saved, free it now
848 delete new_entry;
849 }
850 }
851 return true;
852 } else {
853 return false;
854 }
855 }
856
857 static void print_module_entry_table(const GrowableArray<ModuleClassPathList*>* const module_list) {
858 ResourceMark rm;
859 int num_of_entries = module_list->length();
860 for (int i = 0; i < num_of_entries; i++) {
861 ClassPathEntry* e;
862 ModuleClassPathList* mpl = module_list->at(i);
863 tty->print("%s=", mpl->module_name()->as_C_string());
864 e = mpl->module_first_entry();
865 while (e != nullptr) {
866 tty->print("%s", e->name());
867 e = e->next();
868 if (e != nullptr) {
869 tty->print("%s", os::path_separator());
870 }
871 }
872 tty->print(" ;");
873 }
874 }
875
876 void ClassLoader::print_bootclasspath() {
877 ClassPathEntry* e;
878 tty->print("[bootclasspath= ");
879
880 // Print --patch-module module/path specifications first
881 if (_patch_mod_entries != nullptr) {
882 print_module_entry_table(_patch_mod_entries);
883 }
884
885 // [jimage | exploded modules build]
886 if (has_jrt_entry()) {
887 // Print the location of the java runtime image
888 tty->print("%s ;", _jrt_entry->name());
889 } else {
890 // Print exploded module build path specifications
891 if (_exploded_entries != nullptr) {
892 print_module_entry_table(_exploded_entries);
893 }
894 }
895
896 // appended entries
897 e = first_append_entry();
898 while (e != nullptr) {
899 tty->print("%s ;", e->name());
900 e = e->next();
901 }
902 tty->print_cr("]");
903 }
904
905 void* ClassLoader::dll_lookup(void* lib, const char* name, const char* path) {
906 void* func = os::dll_lookup(lib, name);
907 if (func == nullptr) {
908 char msg[256] = "";
909 jio_snprintf(msg, sizeof(msg), "Could not resolve \"%s\"", name);
910 vm_exit_during_initialization(msg, path);
911 }
912 return func;
913 }
914
915 void ClassLoader::load_java_library() {
916 assert(CanonicalizeEntry == nullptr, "should not load java library twice");
917 void *javalib_handle = os::native_java_library();
918 if (javalib_handle == nullptr) {
919 vm_exit_during_initialization("Unable to load java library", nullptr);
920 }
921
922 CanonicalizeEntry = CAST_TO_FN_PTR(canonicalize_fn_t, dll_lookup(javalib_handle, "JDK_Canonicalize", nullptr));
923 }
924
925 void ClassLoader::load_jimage_library() {
926 assert(JImageOpen == nullptr, "should not load jimage library twice");
927 char path[JVM_MAXPATHLEN];
928 char ebuf[1024];
929 void* handle = nullptr;
930 if (os::dll_locate_lib(path, sizeof(path), Arguments::get_dll_dir(), "jimage")) {
931 handle = os::dll_load(path, ebuf, sizeof ebuf);
932 }
933 if (handle == nullptr) {
934 vm_exit_during_initialization("Unable to load jimage library", path);
935 }
936
937 JImageOpen = CAST_TO_FN_PTR(JImageOpen_t, dll_lookup(handle, "JIMAGE_Open", path));
938 JImageClose = CAST_TO_FN_PTR(JImageClose_t, dll_lookup(handle, "JIMAGE_Close", path));
939 JImageFindResource = CAST_TO_FN_PTR(JImageFindResource_t, dll_lookup(handle, "JIMAGE_FindResource", path));
940 JImageGetResource = CAST_TO_FN_PTR(JImageGetResource_t, dll_lookup(handle, "JIMAGE_GetResource", path));
941 }
942
943 int ClassLoader::crc32(int crc, const char* buf, int len) {
944 return ZipLibrary::crc32(crc, (const jbyte*)buf, len);
945 }
946
947 oop ClassLoader::get_system_package(const char* name, TRAPS) {
948 // Look up the name in the boot loader's package entry table.
949 if (name != nullptr) {
950 TempNewSymbol package_sym = SymbolTable::new_symbol(name);
951 // Look for the package entry in the boot loader's package entry table.
952 PackageEntry* package =
953 ClassLoaderData::the_null_class_loader_data()->packages()->lookup_only(package_sym);
954
955 // Return null if package does not exist or if no classes in that package
956 // have been loaded.
957 if (package != nullptr && package->has_loaded_class()) {
958 ModuleEntry* module = package->module();
959 if (module->location() != nullptr) {
960 ResourceMark rm(THREAD);
961 Handle ml = java_lang_String::create_from_str(
962 module->location()->as_C_string(), THREAD);
963 return ml();
964 }
965 // Return entry on boot loader class path.
966 Handle cph = java_lang_String::create_from_str(
967 ClassLoader::classpath_entry(package->classpath_index())->name(), THREAD);
968 return cph();
969 }
970 }
971 return nullptr;
972 }
973
974 objArrayOop ClassLoader::get_system_packages(TRAPS) {
975 ResourceMark rm(THREAD);
976 // List of pointers to PackageEntrys that have loaded classes.
977 PackageEntryTable* pe_table =
978 ClassLoaderData::the_null_class_loader_data()->packages();
979 GrowableArray<PackageEntry*>* loaded_class_pkgs = pe_table->get_system_packages();
980
981 // Allocate objArray and fill with java.lang.String
982 objArrayOop r = oopFactory::new_objArray(vmClasses::String_klass(),
983 loaded_class_pkgs->length(), CHECK_NULL);
984 objArrayHandle result(THREAD, r);
985 for (int x = 0; x < loaded_class_pkgs->length(); x++) {
986 PackageEntry* package_entry = loaded_class_pkgs->at(x);
987 Handle str = java_lang_String::create_from_symbol(package_entry->name(), CHECK_NULL);
988 result->obj_at_put(x, str());
989 }
990 return result();
991 }
992
993 // caller needs ResourceMark
994 const char* ClassLoader::file_name_for_class_name(const char* class_name,
995 int class_name_len) {
996 assert(class_name != nullptr, "invariant");
997 assert((int)strlen(class_name) == class_name_len, "invariant");
998
999 static const char class_suffix[] = ".class";
1000 size_t class_suffix_len = sizeof(class_suffix);
1001
1002 char* const file_name = NEW_RESOURCE_ARRAY(char,
1003 class_name_len +
1004 class_suffix_len); // includes term null
1005
1006 strncpy(file_name, class_name, class_name_len);
1007 strncpy(&file_name[class_name_len], class_suffix, class_suffix_len);
1008
1009 return file_name;
1010 }
1011
1012 ClassPathEntry* find_first_module_cpe(ModuleEntry* mod_entry,
1013 const GrowableArray<ModuleClassPathList*>* const module_list) {
1014 int num_of_entries = module_list->length();
1015 const Symbol* class_module_name = mod_entry->name();
1016
1017 // Loop through all the modules in either the patch-module or exploded entries looking for module
1018 for (int i = 0; i < num_of_entries; i++) {
1019 ModuleClassPathList* module_cpl = module_list->at(i);
1020 Symbol* module_cpl_name = module_cpl->module_name();
1021
1022 if (module_cpl_name->fast_compare(class_module_name) == 0) {
1023 // Class' module has been located.
1024 return module_cpl->module_first_entry();
1025 }
1026 }
1027 return nullptr;
1028 }
1029
1030
1031 // Search either the patch-module or exploded build entries for class.
1032 ClassFileStream* ClassLoader::search_module_entries(JavaThread* current,
1033 const GrowableArray<ModuleClassPathList*>* const module_list,
1034 const char* const class_name,
1035 const char* const file_name) {
1036 ClassFileStream* stream = nullptr;
1037
1038 // Find the class' defining module in the boot loader's module entry table
1039 TempNewSymbol class_name_symbol = SymbolTable::new_symbol(class_name);
1040 TempNewSymbol pkg_name = package_from_class_name(class_name_symbol);
1041 PackageEntry* pkg_entry = get_package_entry(pkg_name, ClassLoaderData::the_null_class_loader_data());
1042 ModuleEntry* mod_entry = (pkg_entry != nullptr) ? pkg_entry->module() : nullptr;
1043
1044 // If the module system has not defined java.base yet, then
1045 // classes loaded are assumed to be defined to java.base.
1046 // When java.base is eventually defined by the module system,
1047 // all packages of classes that have been previously loaded
1048 // are verified in ModuleEntryTable::verify_javabase_packages().
1049 if (!Universe::is_module_initialized() &&
1050 !ModuleEntryTable::javabase_defined() &&
1051 mod_entry == nullptr) {
1052 mod_entry = ModuleEntryTable::javabase_moduleEntry();
1053 }
1054
1055 // The module must be a named module
1056 ClassPathEntry* e = nullptr;
1057 if (mod_entry != nullptr && mod_entry->is_named()) {
1058 if (module_list == _exploded_entries) {
1059 // The exploded build entries can be added to at any time so a lock is
1060 // needed when searching them.
1061 assert(!ClassLoader::has_jrt_entry(), "Must be exploded build");
1062 MutexLocker ml(current, Module_lock);
1063 e = find_first_module_cpe(mod_entry, module_list);
1064 } else {
1065 e = find_first_module_cpe(mod_entry, module_list);
1066 }
1067 }
1068
1069 // Try to load the class from the module's ClassPathEntry list.
1070 while (e != nullptr) {
1071 stream = e->open_stream(current, file_name);
1072 // No context.check is required since CDS is not supported
1073 // for an exploded modules build or if --patch-module is specified.
1074 if (nullptr != stream) {
1075 return stream;
1076 }
1077 e = e->next();
1078 }
1079 // If the module was located, break out even if the class was not
1080 // located successfully from that module's ClassPathEntry list.
1081 // There will not be another valid entry for that module.
1082 return nullptr;
1083 }
1084
1085 // Called by the boot classloader to load classes
1086 InstanceKlass* ClassLoader::load_class(Symbol* name, bool search_append_only, TRAPS) {
1087 assert(name != nullptr, "invariant");
1088
1089 ResourceMark rm(THREAD);
1090 HandleMark hm(THREAD);
1091
1092 const char* const class_name = name->as_C_string();
1093
1094 EventMarkClassLoading m("Loading class %s", class_name);
1095
1096 const char* const file_name = file_name_for_class_name(class_name,
1097 name->utf8_length());
1098 assert(file_name != nullptr, "invariant");
1099
1100 // Lookup stream for parsing .class file
1101 ClassFileStream* stream = nullptr;
1102 s2 classpath_index = 0;
1103 ClassPathEntry* e = nullptr;
1104 bool is_patched = false;
1105
1106 // If search_append_only is true, boot loader visibility boundaries are
1107 // set to be _first_append_entry to the end. This includes:
1108 // [-Xbootclasspath/a]; [jvmti appended entries]
1109 //
1110 // If search_append_only is false, boot loader visibility boundaries are
1111 // set to be the --patch-module entries plus the base piece. This includes:
1112 // [--patch-module=<module>=<file>(<pathsep><file>)*]; [jimage | exploded module build]
1113 //
1114
1115 // Load Attempt #1: --patch-module
1116 // Determine the class' defining module. If it appears in the _patch_mod_entries,
1117 // attempt to load the class from those locations specific to the module.
1118 // Specifications to --patch-module can contain a partial number of classes
1119 // that are part of the overall module definition. So if a particular class is not
1120 // found within its module specification, the search should continue to Load Attempt #2.
1121 // Note: The --patch-module entries are never searched if the boot loader's
1122 // visibility boundary is limited to only searching the append entries.
1123 if (_patch_mod_entries != nullptr && !search_append_only) {
1124 // At CDS dump time, the --patch-module entries are ignored. That means a
1125 // class is still loaded from the runtime image even if it might
1126 // appear in the _patch_mod_entries. The runtime shared class visibility
1127 // check will determine if a shared class is visible based on the runtime
1128 // environment, including the runtime --patch-module setting.
1129 if (!CDSConfig::is_valhalla_preview()) {
1130 // Dynamic dumping requires UseSharedSpaces to be enabled. Since --patch-module
1131 // is not supported with UseSharedSpaces, we can never come here during dynamic dumping.
1132 assert(!CDSConfig::is_dumping_dynamic_archive(), "sanity");
1133 }
1134 if (CDSConfig::is_valhalla_preview() || !CDSConfig::is_dumping_static_archive()) {
1135 stream = search_module_entries(THREAD, _patch_mod_entries, class_name, file_name);
1136 if (stream != nullptr) {
1137 is_patched = true;
1138 }
1139 }
1140 }
1141
1142 // Load Attempt #2: [jimage | exploded build]
1143 if (!search_append_only && (nullptr == stream)) {
1144 if (has_jrt_entry()) {
1145 e = _jrt_entry;
1146 stream = _jrt_entry->open_stream(THREAD, file_name);
1147 } else {
1148 // Exploded build - attempt to locate class in its defining module's location.
1149 assert(_exploded_entries != nullptr, "No exploded build entries present");
1150 stream = search_module_entries(THREAD, _exploded_entries, class_name, file_name);
1151 }
1152 }
1153
1154 // Load Attempt #3: [-Xbootclasspath/a]; [jvmti appended entries]
1155 if (search_append_only && (nullptr == stream)) {
1156 // For the boot loader append path search, the starting classpath_index
1157 // for the appended piece is always 1 to account for either the
1158 // _jrt_entry or the _exploded_entries.
1159 assert(classpath_index == 0, "The classpath_index has been incremented incorrectly");
1160 classpath_index = 1;
1161
1162 e = first_append_entry();
1163 while (e != nullptr) {
1164 stream = e->open_stream(THREAD, file_name);
1165 if (nullptr != stream) {
1166 break;
1167 }
1168 e = e->next();
1169 ++classpath_index;
1170 }
1171 }
1172
1173 if (nullptr == stream) {
1174 return nullptr;
1175 }
1176
1177 stream->set_verify(ClassLoaderExt::should_verify(classpath_index));
1178
1179 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
1180 Handle protection_domain;
1181 ClassLoadInfo cl_info(protection_domain);
1182
1183 InstanceKlass* result = KlassFactory::create_from_stream(stream,
1184 name,
1185 loader_data,
1186 cl_info,
1187 CHECK_NULL);
1188 result->set_classpath_index(classpath_index);
1189 if (is_patched) {
1190 result->set_shared_classpath_index(0);
1191 result->set_shared_class_loader_type(ClassLoader::BOOT_LOADER);
1192 }
1193 return result;
1194 }
1195
1196 #if INCLUDE_CDS
1197 char* ClassLoader::skip_uri_protocol(char* source) {
1198 if (strncmp(source, "file:", 5) == 0) {
1199 // file: protocol path could start with file:/ or file:///
1200 // locate the char after all the forward slashes
1201 int offset = 5;
1202 while (*(source + offset) == '/') {
1203 offset++;
1204 }
1205 source += offset;
1206 // for non-windows platforms, move back one char as the path begins with a '/'
1207 #ifndef _WINDOWS
1208 source -= 1;
1209 #endif
1210 } else if (strncmp(source, "jrt:/", 5) == 0) {
1211 source += 5;
1212 }
1213 return source;
1214 }
1215
1216 // Record the shared classpath index and loader type for classes loaded
1217 // by the builtin loaders at dump time.
1218 void ClassLoader::record_result(JavaThread* current, InstanceKlass* ik,
1219 const ClassFileStream* stream, bool redefined) {
1220 assert(CDSConfig::is_dumping_archive(), "sanity");
1221 assert(stream != nullptr, "sanity");
1222
1223 if (ik->is_hidden()) {
1224 // We do not archive hidden classes.
1225 return;
1226 }
1227
1228 if (ik->shared_classpath_index() == 0 && ik->is_shared_boot_class()) {
1229 return;
1230 }
1231
1232 oop loader = ik->class_loader();
1233 char* src = (char*)stream->source();
1234 if (src == nullptr) {
1235 if (loader == nullptr) {
1236 // JFR classes
1237 ik->set_shared_classpath_index(0);
1238 ik->set_shared_class_loader_type(ClassLoader::BOOT_LOADER);
1239 }
1240 return;
1241 }
1242
1243 assert(has_jrt_entry(), "CDS dumping does not support exploded JDK build");
1244
1245 ResourceMark rm(current);
1246 int classpath_index = -1;
1247 PackageEntry* pkg_entry = ik->package();
1248
1249 if (FileMapInfo::get_number_of_shared_paths() > 0) {
1250 // Save the path from the file: protocol or the module name from the jrt: protocol
1251 // if no protocol prefix is found, path is the same as stream->source(). This path
1252 // must be valid since the class has been successfully parsed.
1253 char* path = skip_uri_protocol(src);
1254 assert(path != nullptr, "sanity");
1255 for (int i = 0; i < FileMapInfo::get_number_of_shared_paths(); i++) {
1256 SharedClassPathEntry* ent = FileMapInfo::shared_path(i);
1257 // A shared path has been validated during its creation in ClassLoader::create_class_path_entry(),
1258 // it must be valid here.
1259 assert(ent->name() != nullptr, "sanity");
1260 // If the path (from the class stream source) is the same as the shared
1261 // class or module path, then we have a match.
1262 // src may come from the App/Platform class loaders, which would canonicalize
1263 // the file name. We cannot use strcmp to check for equality against ent->name().
1264 // We must use os::same_files (which is faster than canonicalizing ent->name()).
1265 if (os::same_files(ent->name(), path)) {
1266 // null pkg_entry and pkg_entry in an unnamed module implies the class
1267 // is from the -cp or boot loader append path which consists of -Xbootclasspath/a
1268 // and jvmti appended entries.
1269 if ((pkg_entry == nullptr) || (pkg_entry->in_unnamed_module())) {
1270 // Ensure the index is within the -cp range before assigning
1271 // to the classpath_index.
1272 if (SystemDictionary::is_system_class_loader(loader) &&
1273 (i >= ClassLoaderExt::app_class_paths_start_index()) &&
1274 (i < ClassLoaderExt::app_module_paths_start_index())) {
1275 classpath_index = i;
1276 break;
1277 } else {
1278 if ((i >= 1) &&
1279 (i < ClassLoaderExt::app_class_paths_start_index())) {
1280 // The class must be from boot loader append path which consists of
1281 // -Xbootclasspath/a and jvmti appended entries.
1282 assert(loader == nullptr, "sanity");
1283 classpath_index = i;
1284 break;
1285 }
1286 }
1287 } else {
1288 // A class from a named module from the --module-path. Ensure the index is
1289 // within the --module-path range before assigning to the classpath_index.
1290 if ((pkg_entry != nullptr) && !(pkg_entry->in_unnamed_module()) && (i > 0)) {
1291 if (i >= ClassLoaderExt::app_module_paths_start_index() &&
1292 i < FileMapInfo::get_number_of_shared_paths()) {
1293 classpath_index = i;
1294 break;
1295 }
1296 }
1297 }
1298 }
1299 // for index 0 and the stream->source() is the modules image or has the jrt: protocol.
1300 // The class must be from the runtime modules image.
1301 if (i == 0 && (stream->from_boot_loader_modules_image() || string_starts_with(src, "jrt:"))) {
1302 classpath_index = i;
1303 break;
1304 }
1305 }
1306
1307 // No path entry found for this class: most likely a shared class loaded by the
1308 // user defined classloader.
1309 if (classpath_index < 0 && !SystemDictionaryShared::is_builtin_loader(ik->class_loader_data())) {
1310 assert(ik->shared_classpath_index() < 0, "not assigned yet");
1311 ik->set_shared_classpath_index(UNREGISTERED_INDEX);
1312 SystemDictionaryShared::set_shared_class_misc_info(ik, (ClassFileStream*)stream);
1313 return;
1314 }
1315 } else {
1316 // The shared path table is set up after module system initialization.
1317 // The path table contains no entry before that. Any classes loaded prior
1318 // to the setup of the shared path table must be from the modules image.
1319 if (!CDSConfig::is_valhalla_preview()) {
1320 assert(stream->from_boot_loader_modules_image(), "stream must be loaded by boot loader from modules image");
1321 }
1322 assert(FileMapInfo::get_number_of_shared_paths() == 0, "shared path table must not have been setup");
1323 classpath_index = 0;
1324 }
1325
1326 const char* const class_name = ik->name()->as_C_string();
1327 const char* const file_name = file_name_for_class_name(class_name,
1328 ik->name()->utf8_length());
1329 assert(file_name != nullptr, "invariant");
1330 ClassLoaderExt::record_result(checked_cast<s2>(classpath_index), ik, redefined);
1331 }
1332 #endif // INCLUDE_CDS
1333
1334 // Initialize the class loader's access to methods in libzip. Parse and
1335 // process the boot classpath into a list ClassPathEntry objects. Once
1336 // this list has been created, it must not change order (see class PackageInfo)
1337 // it can be appended to and is by jvmti.
1338
1339 void ClassLoader::initialize(TRAPS) {
1340 if (UsePerfData) {
1341 // jvmstat performance counters
1342 NEWPERFTICKCOUNTER(_perf_accumulated_time, SUN_CLS, "time");
1343 NEWPERFTICKCOUNTER(_perf_class_init_time, SUN_CLS, "classInitTime");
1344 NEWPERFTICKCOUNTER(_perf_class_init_selftime, SUN_CLS, "classInitTime.self");
1345 NEWPERFTICKCOUNTER(_perf_class_verify_time, SUN_CLS, "classVerifyTime");
1346 NEWPERFTICKCOUNTER(_perf_class_verify_selftime, SUN_CLS, "classVerifyTime.self");
1347 NEWPERFTICKCOUNTER(_perf_class_link_time, SUN_CLS, "classLinkedTime");
1348 NEWPERFTICKCOUNTER(_perf_class_link_selftime, SUN_CLS, "classLinkedTime.self");
1349 NEWPERFEVENTCOUNTER(_perf_classes_inited, SUN_CLS, "initializedClasses");
1350 NEWPERFEVENTCOUNTER(_perf_classes_linked, SUN_CLS, "linkedClasses");
1351 NEWPERFEVENTCOUNTER(_perf_classes_verified, SUN_CLS, "verifiedClasses");
1352
1353 NEWPERFTICKCOUNTER(_perf_shared_classload_time, SUN_CLS, "sharedClassLoadTime");
1354 NEWPERFTICKCOUNTER(_perf_sys_classload_time, SUN_CLS, "sysClassLoadTime");
1355 NEWPERFTICKCOUNTER(_perf_app_classload_time, SUN_CLS, "appClassLoadTime");
1356 NEWPERFTICKCOUNTER(_perf_app_classload_selftime, SUN_CLS, "appClassLoadTime.self");
1357 NEWPERFEVENTCOUNTER(_perf_app_classload_count, SUN_CLS, "appClassLoadCount");
1358 NEWPERFTICKCOUNTER(_perf_define_appclasses, SUN_CLS, "defineAppClasses");
1359 NEWPERFTICKCOUNTER(_perf_define_appclass_time, SUN_CLS, "defineAppClassTime");
1360 NEWPERFTICKCOUNTER(_perf_define_appclass_selftime, SUN_CLS, "defineAppClassTime.self");
1361 NEWPERFBYTECOUNTER(_perf_app_classfile_bytes_read, SUN_CLS, "appClassBytes");
1362 NEWPERFBYTECOUNTER(_perf_sys_classfile_bytes_read, SUN_CLS, "sysClassBytes");
1363
1364 NEWPERFEVENTCOUNTER(_unsafe_defineClassCallCounter, SUN_CLS, "unsafeDefineClassCalls");
1365 }
1366
1367 // lookup java library entry points
1368 load_java_library();
1369 // jimage library entry points are loaded below, in lookup_vm_options
1370 setup_bootstrap_search_path(THREAD);
1371 }
1372
1373 char* lookup_vm_resource(JImageFile *jimage, const char *jimage_version, const char *path) {
1374 jlong size;
1375 JImageLocationRef location = (*JImageFindResource)(jimage, "java.base", jimage_version, path, &size);
1376 if (location == 0)
1377 return nullptr;
1378 char *val = NEW_C_HEAP_ARRAY(char, size+1, mtClass);
1379 (*JImageGetResource)(jimage, location, val, size);
1380 val[size] = '\0';
1381 return val;
1382 }
1383
1384 // Lookup VM options embedded in the modules jimage file
1385 char* ClassLoader::lookup_vm_options() {
1386 jint error;
1387 char modules_path[JVM_MAXPATHLEN];
1388 const char* fileSep = os::file_separator();
1389
1390 // Initialize jimage library entry points
1391 load_jimage_library();
1392
1393 jio_snprintf(modules_path, JVM_MAXPATHLEN, "%s%slib%smodules", Arguments::get_java_home(), fileSep, fileSep);
1394 JImage_file =(*JImageOpen)(modules_path, &error);
1395 if (JImage_file == nullptr) {
1396 return nullptr;
1397 }
1398
1399 const char *jimage_version = get_jimage_version_string();
1400 char *options = lookup_vm_resource(JImage_file, jimage_version, "jdk/internal/vm/options");
1401 return options;
1402 }
1403
1404 bool ClassLoader::is_module_observable(const char* module_name) {
1405 assert(JImageOpen != nullptr, "jimage library should have been opened");
1406 if (JImage_file == nullptr) {
1407 struct stat st;
1408 const char *path = get_exploded_module_path(module_name, true);
1409 bool res = os::stat(path, &st) == 0;
1410 FREE_C_HEAP_ARRAY(char, path);
1411 return res;
1412 }
1413 jlong size;
1414 const char *jimage_version = get_jimage_version_string();
1415 return (*JImageFindResource)(JImage_file, module_name, jimage_version, "module-info.class", &size) != 0;
1416 }
1417
1418 #if INCLUDE_CDS
1419 void ClassLoader::initialize_shared_path(JavaThread* current) {
1420 if (CDSConfig::is_dumping_archive()) {
1421 ClassLoaderExt::setup_search_paths(current);
1422 }
1423 }
1424
1425 void ClassLoader::initialize_module_path(TRAPS) {
1426 if (CDSConfig::is_dumping_archive()) {
1427 ClassLoaderExt::setup_module_paths(THREAD);
1428 FileMapInfo::allocate_shared_path_table(CHECK);
1429 }
1430 }
1431
1432 // Helper function used by CDS code to get the number of module path
1433 // entries during shared classpath setup time.
1434 int ClassLoader::num_module_path_entries() {
1435 assert(CDSConfig::is_dumping_archive(), "sanity");
1436 int num_entries = 0;
1437 ClassPathEntry* e= ClassLoader::_module_path_entries;
1438 while (e != nullptr) {
1439 num_entries ++;
1440 e = e->next();
1441 }
1442 return num_entries;
1443 }
1444 #endif
1445
1446 jlong ClassLoader::classloader_time_ms() {
1447 return UsePerfData ?
1448 Management::ticks_to_ms(_perf_accumulated_time->get_value()) : -1;
1449 }
1450
1451 jlong ClassLoader::class_init_count() {
1452 return UsePerfData ? _perf_classes_inited->get_value() : -1;
1453 }
1454
1455 jlong ClassLoader::class_init_time_ms() {
1456 return UsePerfData ?
1457 Management::ticks_to_ms(_perf_class_init_time->get_value()) : -1;
1458 }
1459
1460 jlong ClassLoader::class_verify_time_ms() {
1461 return UsePerfData ?
1462 Management::ticks_to_ms(_perf_class_verify_time->get_value()) : -1;
1463 }
1464
1465 jlong ClassLoader::class_link_count() {
1466 return UsePerfData ? _perf_classes_linked->get_value() : -1;
1467 }
1468
1469 jlong ClassLoader::class_link_time_ms() {
1470 return UsePerfData ?
1471 Management::ticks_to_ms(_perf_class_link_time->get_value()) : -1;
1472 }
1473
1474 int ClassLoader::compute_Object_vtable() {
1475 // hardwired for JDK1.2 -- would need to duplicate class file parsing
1476 // code to determine actual value from file
1477 // Would be value '11' if finals were in vtable
1478 int JDK_1_2_Object_vtable_size = 5;
1479 return JDK_1_2_Object_vtable_size * vtableEntry::size();
1480 }
1481
1482
1483 void classLoader_init1() {
1484 EXCEPTION_MARK;
1485 ClassLoader::initialize(THREAD);
1486 if (HAS_PENDING_EXCEPTION) {
1487 vm_exit_during_initialization("ClassLoader::initialize() failed unexpectedly");
1488 }
1489 }
1490
1491 // Complete the ClassPathEntry setup for the boot loader
1492 void ClassLoader::classLoader_init2(JavaThread* current) {
1493 // Setup the list of module/path pairs for --patch-module processing
1494 // This must be done after the SymbolTable is created in order
1495 // to use fast_compare on module names instead of a string compare.
1496 if (Arguments::get_patch_mod_prefix() != nullptr) {
1497 setup_patch_mod_entries();
1498 }
1499
1500 // Create the ModuleEntry for java.base (must occur after setup_patch_mod_entries
1501 // to successfully determine if java.base has been patched)
1502 create_javabase();
1503
1504 // Setup the initial java.base/path pair for the exploded build entries.
1505 // As more modules are defined during module system initialization, more
1506 // entries will be added to the exploded build array.
1507 if (!has_jrt_entry()) {
1508 assert(!CDSConfig::is_dumping_archive(), "not supported with exploded module builds");
1509 assert(!UseSharedSpaces, "UsedSharedSpaces not supported with exploded module builds");
1510 // Set up the boot loader's _exploded_entries list. Note that this gets
1511 // done before loading any classes, by the same thread that will
1512 // subsequently do the first class load. So, no lock is needed for this.
1513 assert(_exploded_entries == nullptr, "Should only get initialized once");
1514 _exploded_entries = new (mtModule)
1515 GrowableArray<ModuleClassPathList*>(EXPLODED_ENTRY_SIZE, mtModule);
1516 add_to_exploded_build_list(current, vmSymbols::java_base());
1517 }
1518 }
1519
1520 char* ClassLoader::get_canonical_path(const char* orig, Thread* thread) {
1521 assert(orig != nullptr, "bad arguments");
1522 // caller needs to allocate ResourceMark for the following output buffer
1523 char* canonical_path = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, JVM_MAXPATHLEN);
1524 ResourceMark rm(thread);
1525 // os::native_path writes into orig_copy
1526 char* orig_copy = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, strlen(orig)+1);
1527 strcpy(orig_copy, orig);
1528 if ((CanonicalizeEntry)(os::native_path(orig_copy), canonical_path, JVM_MAXPATHLEN) < 0) {
1529 return nullptr;
1530 }
1531 return canonical_path;
1532 }
1533
1534 void ClassLoader::create_javabase() {
1535 JavaThread* current = JavaThread::current();
1536
1537 // Create java.base's module entry for the boot
1538 // class loader prior to loading j.l.Object.
1539 ClassLoaderData* null_cld = ClassLoaderData::the_null_class_loader_data();
1540
1541 // Get module entry table
1542 ModuleEntryTable* null_cld_modules = null_cld->modules();
1543 if (null_cld_modules == nullptr) {
1544 vm_exit_during_initialization("No ModuleEntryTable for the boot class loader");
1545 }
1546
1547 {
1548 MutexLocker ml(current, Module_lock);
1549 if (ModuleEntryTable::javabase_moduleEntry() == nullptr) { // may have been inited by CDS.
1550 ModuleEntry* jb_module = null_cld_modules->locked_create_entry(Handle(),
1551 false, vmSymbols::java_base(), nullptr, nullptr, null_cld);
1552 if (jb_module == nullptr) {
1553 vm_exit_during_initialization("Unable to create ModuleEntry for " JAVA_BASE_NAME);
1554 }
1555 ModuleEntryTable::set_javabase_moduleEntry(jb_module);
1556 }
1557 }
1558 }
1559
1560 // Please keep following two functions at end of this file. With them placed at top or in middle of the file,
1561 // they could get inlined by aggressive compiler, an unknown trick, see bug 6966589.
1562 void PerfClassTraceTime::initialize() {
1563 if (!UsePerfData) return;
1564
1565 if (_eventp != nullptr) {
1566 // increment the event counter
1567 _eventp->inc();
1568 }
1569
1570 // stop the current active thread-local timer to measure inclusive time
1571 _prev_active_event = -1;
1572 for (int i=0; i < EVENT_TYPE_COUNT; i++) {
1573 if (_timers[i].is_active()) {
1574 assert(_prev_active_event == -1, "should have only one active timer");
1575 _prev_active_event = i;
1576 _timers[i].stop();
1577 }
1578 }
1579
1580 if (_recursion_counters == nullptr || (_recursion_counters[_event_type])++ == 0) {
1581 // start the inclusive timer if not recursively called
1582 _t.start();
1583 }
1584
1585 // start thread-local timer of the given event type
1586 if (!_timers[_event_type].is_active()) {
1587 _timers[_event_type].start();
1588 }
1589 }
1590
1591 PerfClassTraceTime::~PerfClassTraceTime() {
1592 if (!UsePerfData) return;
1593
1594 // stop the thread-local timer as the event completes
1595 // and resume the thread-local timer of the event next on the stack
1596 _timers[_event_type].stop();
1597 jlong selftime = _timers[_event_type].ticks();
1598
1599 if (_prev_active_event >= 0) {
1600 _timers[_prev_active_event].start();
1601 }
1602
1603 if (_recursion_counters != nullptr && --(_recursion_counters[_event_type]) > 0) return;
1604
1605 // increment the counters only on the leaf call
1606 _t.stop();
1607 _timep->inc(_t.ticks());
1608 if (_selftimep != nullptr) {
1609 _selftimep->inc(selftime);
1610 }
1611 // add all class loading related event selftime to the accumulated time counter
1612 ClassLoader::perf_accumulated_time()->inc(selftime);
1613
1614 // reset the timer
1615 _timers[_event_type].reset();
1616 }