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 #if INCLUDE_CDS
138 static bool string_starts_with(const char* str, const char* str_to_find) {
139 size_t str_len = strlen(str);
140 size_t str_to_find_len = strlen(str_to_find);
141 if (str_to_find_len > str_len) {
142 return false;
143 }
144 return (strncmp(str, str_to_find, str_to_find_len) == 0);
145 }
146 #endif
147
148 static const char* get_jimage_version_string() {
149 static char version_string[10] = "";
150 if (version_string[0] == '\0') {
151 jio_snprintf(version_string, sizeof(version_string), "%d.%d",
152 VM_Version::vm_major_version(), VM_Version::vm_minor_version());
153 }
154 return (const char*)version_string;
155 }
156
157 bool ClassLoader::string_ends_with(const char* str, const char* str_to_find) {
158 size_t str_len = strlen(str);
159 size_t str_to_find_len = strlen(str_to_find);
160 if (str_to_find_len > str_len) {
161 return false;
162 }
163 return (strncmp(str + (str_len - str_to_find_len), str_to_find, str_to_find_len) == 0);
164 }
165
166 // Used to obtain the package name from a fully qualified class name.
167 Symbol* ClassLoader::package_from_class_name(const Symbol* name, bool* bad_class_name) {
168 if (name == nullptr) {
169 if (bad_class_name != nullptr) {
170 *bad_class_name = true;
171 }
172 return nullptr;
173 }
174
175 int utf_len = name->utf8_length();
176 const jbyte* base = (const jbyte*)name->base();
177 const jbyte* start = base;
178 const jbyte* end = UTF8::strrchr(start, utf_len, JVM_SIGNATURE_SLASH);
179 if (end == nullptr) {
180 return nullptr;
181 }
182 // Skip over '['s
183 if (*start == JVM_SIGNATURE_ARRAY) {
184 do {
185 start++;
186 } while (start < end && *start == JVM_SIGNATURE_ARRAY);
187
188 // Fully qualified class names should not contain a 'L'.
189 // Set bad_class_name to true to indicate that the package name
190 // could not be obtained due to an error condition.
191 // In this situation, is_same_class_package returns false.
192 if (*start == JVM_SIGNATURE_CLASS) {
193 if (bad_class_name != nullptr) {
194 *bad_class_name = true;
195 }
196 return nullptr;
197 }
198 }
199 // A class name could have just the slash character in the name,
200 // in which case start > end
201 if (start >= end) {
202 // No package name
203 if (bad_class_name != nullptr) {
204 *bad_class_name = true;
205 }
206 return nullptr;
207 }
208 return SymbolTable::new_symbol(name, pointer_delta_as_int(start, base), pointer_delta_as_int(end, base));
209 }
210
211 // Given a fully qualified package name, find its defining package in the class loader's
212 // package entry table.
213 PackageEntry* ClassLoader::get_package_entry(Symbol* pkg_name, ClassLoaderData* loader_data) {
214 if (pkg_name == nullptr) {
215 return nullptr;
216 }
217 PackageEntryTable* pkgEntryTable = loader_data->packages();
218 return pkgEntryTable->lookup_only(pkg_name);
219 }
220
221 const char* ClassPathEntry::copy_path(const char* path) {
222 char* copy = NEW_C_HEAP_ARRAY(char, strlen(path)+1, mtClass);
223 strcpy(copy, path);
224 return copy;
225 }
226
227 ClassPathDirEntry::~ClassPathDirEntry() {
228 FREE_C_HEAP_ARRAY(char, _dir);
229 }
230
231 ClassFileStream* ClassPathDirEntry::open_stream(JavaThread* current, const char* name) {
232 // construct full path name
233 assert((_dir != nullptr) && (name != nullptr), "sanity");
234 size_t path_len = strlen(_dir) + strlen(name) + strlen(os::file_separator()) + 1;
235 char* path = NEW_RESOURCE_ARRAY_IN_THREAD(current, char, path_len);
236 int len = jio_snprintf(path, path_len, "%s%s%s", _dir, os::file_separator(), name);
237 assert(len == (int)(path_len - 1), "sanity");
238 // check if file exists
239 struct stat st;
240 if (os::stat(path, &st) == 0) {
241 // found file, open it
242 int file_handle = os::open(path, 0, 0);
243 if (file_handle != -1) {
244 // read contents into resource array
245 u1* buffer = NEW_RESOURCE_ARRAY_IN_THREAD(current, u1, st.st_size);
246 size_t num_read = ::read(file_handle, (char*) buffer, st.st_size);
247 // close file
248 ::close(file_handle);
249 // construct ClassFileStream
250 if (num_read == (size_t)st.st_size) {
251 if (UsePerfData) {
252 ClassLoader::perf_sys_classfile_bytes_read()->inc(num_read);
253 }
254 #ifdef ASSERT
255 // Freeing path is a no-op here as buffer prevents it from being reclaimed. But we keep it for
256 // debug builds so that we guard against use-after-free bugs.
257 FREE_RESOURCE_ARRAY_IN_THREAD(current, char, path, path_len);
258 #endif
259 // We don't verify the length of the classfile stream fits in an int, but this is the
260 // bootloader so we have control of this.
261 // Resource allocated
262 return new ClassFileStream(buffer,
263 checked_cast<int>(st.st_size),
264 _dir,
265 ClassFileStream::verify);
266 }
267 }
268 }
269 FREE_RESOURCE_ARRAY_IN_THREAD(current, char, path, path_len);
270 return nullptr;
271 }
272
273 ClassPathZipEntry::ClassPathZipEntry(jzfile* zip, const char* zip_name,
274 bool is_boot_append, bool from_class_path_attr) : ClassPathEntry() {
275 _zip = zip;
276 _zip_name = copy_path(zip_name);
277 _from_class_path_attr = from_class_path_attr;
278 }
279
280 ClassPathZipEntry::~ClassPathZipEntry() {
281 ZipLibrary::close(_zip);
282 FREE_C_HEAP_ARRAY(char, _zip_name);
283 }
284
285 u1* ClassPathZipEntry::open_entry(JavaThread* current, const char* name, jint* filesize, bool nul_terminate) {
286 // enable call to C land
287 ThreadToNativeFromVM ttn(current);
288 // check whether zip archive contains name
289 jint name_len;
290 jzentry* entry = ZipLibrary::find_entry(_zip, name, filesize, &name_len);
291 if (entry == nullptr) return nullptr;
292 u1* buffer;
293 char name_buf[128];
294 char* filename;
295 if (name_len < 128) {
296 filename = name_buf;
297 } else {
298 filename = NEW_RESOURCE_ARRAY(char, name_len + 1);
299 }
300
301 // read contents into resource array
302 size_t size = (uint32_t)(*filesize);
303 if (nul_terminate) {
304 if (sizeof(size) == sizeof(uint32_t) && size == UINT_MAX) {
305 return nullptr; // 32-bit integer overflow will occur.
306 }
307 size++;
308 }
309 buffer = NEW_RESOURCE_ARRAY(u1, size);
310 if (!ZipLibrary::read_entry(_zip, entry, buffer, filename)) {
311 return nullptr;
312 }
313
314 // return result
315 if (nul_terminate) {
316 buffer[size - 1] = 0;
317 }
318 return buffer;
319 }
320
321 ClassFileStream* ClassPathZipEntry::open_stream(JavaThread* current, const char* name) {
322 jint filesize;
323 u1* buffer = open_entry(current, name, &filesize, false);
324 if (buffer == nullptr) {
325 return nullptr;
326 }
327 if (UsePerfData) {
328 ClassLoader::perf_sys_classfile_bytes_read()->inc(filesize);
329 }
330 // Resource allocated
331 return new ClassFileStream(buffer,
332 filesize,
333 _zip_name,
334 ClassFileStream::verify);
335 }
336
337 DEBUG_ONLY(ClassPathImageEntry* ClassPathImageEntry::_singleton = nullptr;)
338
339 JImageFile* ClassPathImageEntry::jimage() const {
340 return JImage_file;
341 }
342
343 JImageFile* ClassPathImageEntry::jimage_non_null() const {
344 assert(ClassLoader::has_jrt_entry(), "must be");
345 assert(jimage() != nullptr, "should have been opened by ClassLoader::lookup_vm_options "
346 "and remained throughout normal JVM lifetime");
347 return jimage();
348 }
349
350 void ClassPathImageEntry::close_jimage() {
351 if (jimage() != nullptr) {
352 (*JImageClose)(jimage());
353 JImage_file = nullptr;
354 }
355 }
356
357 ClassPathImageEntry::ClassPathImageEntry(JImageFile* jimage, const char* name) :
358 ClassPathEntry() {
359 guarantee(jimage != nullptr, "jimage file is null");
360 guarantee(name != nullptr, "jimage file name is null");
361 assert(_singleton == nullptr, "VM supports only one jimage");
362 DEBUG_ONLY(_singleton = this);
363 size_t len = strlen(name) + 1;
364 _name = copy_path(name);
365 }
366
367 ClassFileStream* ClassPathImageEntry::open_stream(JavaThread* current, const char* name) {
368 return open_stream_for_loader(current, name, ClassLoaderData::the_null_class_loader_data());
369 }
370
371 // For a class in a named module, look it up in the jimage file using this syntax:
372 // /<module-name>/<package-name>/<base-class>
373 //
374 // Assumptions:
375 // 1. There are no unnamed modules in the jimage file.
376 // 2. A package is in at most one module in the jimage file.
377 //
378 ClassFileStream* ClassPathImageEntry::open_stream_for_loader(JavaThread* current, const char* name, ClassLoaderData* loader_data) {
379 jlong size;
380 JImageLocationRef location = (*JImageFindResource)(jimage_non_null(), "", get_jimage_version_string(), name, &size);
381
382 if (location == 0) {
383 TempNewSymbol class_name = SymbolTable::new_symbol(name);
384 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
385
386 if (pkg_name != nullptr) {
387 if (!Universe::is_module_initialized()) {
388 location = (*JImageFindResource)(jimage_non_null(), JAVA_BASE_NAME, get_jimage_version_string(), name, &size);
389 } else {
390 PackageEntry* package_entry = ClassLoader::get_package_entry(pkg_name, loader_data);
391 if (package_entry != nullptr) {
392 ResourceMark rm(current);
393 // Get the module name
394 ModuleEntry* module = package_entry->module();
395 assert(module != nullptr, "Boot classLoader package missing module");
396 assert(module->is_named(), "Boot classLoader package is in unnamed module");
397 const char* module_name = module->name()->as_C_string();
398 if (module_name != nullptr) {
399 location = (*JImageFindResource)(jimage_non_null(), module_name, get_jimage_version_string(), name, &size);
400 }
401 }
402 }
403 }
404 }
405 if (location != 0) {
406 if (UsePerfData) {
407 ClassLoader::perf_sys_classfile_bytes_read()->inc(size);
408 }
409 char* data = NEW_RESOURCE_ARRAY(char, size);
410 (*JImageGetResource)(jimage_non_null(), location, data, size);
411 // Resource allocated
412 assert(this == (ClassPathImageEntry*)ClassLoader::get_jrt_entry(), "must be");
413 return new ClassFileStream((u1*)data,
414 checked_cast<int>(size),
415 _name,
416 ClassFileStream::verify,
417 true); // from_boot_loader_modules_image
418 }
419
420 return nullptr;
421 }
422
423 JImageLocationRef ClassLoader::jimage_find_resource(JImageFile* jf,
424 const char* module_name,
425 const char* file_name,
426 jlong &size) {
427 return ((*JImageFindResource)(jf, module_name, get_jimage_version_string(), file_name, &size));
428 }
429
430 bool ClassPathImageEntry::is_modules_image() const {
431 assert(this == _singleton, "VM supports a single jimage");
432 assert(this == (ClassPathImageEntry*)ClassLoader::get_jrt_entry(), "must be used for jrt entry");
433 return true;
434 }
435
436 #if INCLUDE_CDS
437 void ClassLoader::exit_with_path_failure(const char* error, const char* message) {
438 assert(CDSConfig::is_dumping_archive(), "sanity");
439 tty->print_cr("Hint: enable -Xlog:class+path=info to diagnose the failure");
440 vm_exit_during_initialization(error, message);
441 }
442 #endif
443
444 ModuleClassPathList::ModuleClassPathList(Symbol* module_name) {
445 _module_name = module_name;
446 _module_first_entry = nullptr;
447 _module_last_entry = nullptr;
448 }
449
450 ModuleClassPathList::~ModuleClassPathList() {
451 // Clean out each ClassPathEntry on list
452 ClassPathEntry* e = _module_first_entry;
453 while (e != nullptr) {
454 ClassPathEntry* next_entry = e->next();
455 delete e;
456 e = next_entry;
457 }
458 }
459
460 void ModuleClassPathList::add_to_list(ClassPathEntry* new_entry) {
461 if (new_entry != nullptr) {
462 if (_module_last_entry == nullptr) {
463 _module_first_entry = _module_last_entry = new_entry;
464 } else {
465 _module_last_entry->set_next(new_entry);
466 _module_last_entry = new_entry;
467 }
468 }
469 }
470
471 void ClassLoader::trace_class_path(const char* msg, const char* name) {
472 LogTarget(Info, class, path) lt;
473 if (lt.is_enabled()) {
474 LogStream ls(lt);
475 if (msg) {
476 ls.print("%s", msg);
477 }
478 if (name) {
479 if (strlen(name) < 256) {
480 ls.print("%s", name);
481 } else {
482 // For very long paths, we need to print each character separately,
483 // as print_cr() has a length limit
484 while (name[0] != '\0') {
485 ls.print("%c", name[0]);
486 name++;
487 }
488 }
489 }
490 ls.cr();
491 }
492 }
493
494 void ClassLoader::setup_bootstrap_search_path(JavaThread* current) {
495 const char* bootcp = Arguments::get_boot_class_path();
496 assert(bootcp != nullptr, "Boot class path must not be nullptr");
497 if (PrintSharedArchiveAndExit) {
498 // Don't print bootcp - this is the bootcp of this current VM process, not necessarily
499 // the same as the boot classpath of the shared archive.
500 } else {
501 trace_class_path("bootstrap loader class path=", bootcp);
502 }
503 setup_bootstrap_search_path_impl(current, bootcp);
504 }
505
506 #if INCLUDE_CDS
507 void ClassLoader::setup_app_search_path(JavaThread* current, const char *class_path) {
508 assert(CDSConfig::is_dumping_archive(), "sanity");
509
510 ResourceMark rm(current);
511 ClasspathStream cp_stream(class_path);
512
513 while (cp_stream.has_next()) {
514 const char* path = cp_stream.get_next();
515 update_class_path_entry_list(current, path, /* check_for_duplicates */ true,
516 /* is_boot_append */ false, /* from_class_path_attr */ false);
517 }
518 }
519
520 void ClassLoader::add_to_module_path_entries(const char* path,
521 ClassPathEntry* entry) {
522 assert(entry != nullptr, "ClassPathEntry should not be nullptr");
523 assert(CDSConfig::is_dumping_archive(), "sanity");
524
525 // The entry does not exist, add to the list
526 if (_module_path_entries == nullptr) {
527 assert(_last_module_path_entry == nullptr, "Sanity");
528 _module_path_entries = _last_module_path_entry = entry;
529 } else {
530 _last_module_path_entry->set_next(entry);
531 _last_module_path_entry = entry;
532 }
533 }
534
535 // Add a module path to the _module_path_entries list.
536 void ClassLoader::setup_module_search_path(JavaThread* current, const char* path) {
537 assert(CDSConfig::is_dumping_archive(), "sanity");
538 struct stat st;
539 if (os::stat(path, &st) != 0) {
540 tty->print_cr("os::stat error %d (%s). CDS dump aborted (path was \"%s\").",
541 errno, os::errno_name(errno), path);
542 vm_exit_during_initialization();
543 }
544 // File or directory found
545 ClassPathEntry* new_entry = nullptr;
546 new_entry = create_class_path_entry(current, path, &st,
547 false /*is_boot_append */, false /* from_class_path_attr */);
548 if (new_entry != nullptr) {
549 add_to_module_path_entries(path, new_entry);
550 }
551 }
552
553 #endif // INCLUDE_CDS
554
555 void ClassLoader::close_jrt_image() {
556 // Not applicable for exploded builds
557 if (!ClassLoader::has_jrt_entry()) return;
558 _jrt_entry->close_jimage();
559 }
560
561 // Construct the array of module/path pairs as specified to --patch-module
562 // for the boot loader to search ahead of the jimage, if the class being
563 // loaded is defined to a module that has been specified to --patch-module.
564 void ClassLoader::setup_patch_mod_entries() {
565 JavaThread* current = JavaThread::current();
566 GrowableArray<ModulePatchPath*>* patch_mod_args = Arguments::get_patch_mod_prefix();
567 int num_of_entries = patch_mod_args->length();
568
569 // Set up the boot loader's _patch_mod_entries list
570 _patch_mod_entries = new (mtModule) GrowableArray<ModuleClassPathList*>(num_of_entries, mtModule);
571
572 for (int i = 0; i < num_of_entries; i++) {
573 const char* module_name = (patch_mod_args->at(i))->module_name();
574 Symbol* const module_sym = SymbolTable::new_symbol(module_name);
575 assert(module_sym != nullptr, "Failed to obtain Symbol for module name");
576 ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
577
578 char* class_path = (patch_mod_args->at(i))->path_string();
579 ResourceMark rm(current);
580 ClasspathStream cp_stream(class_path);
581
582 while (cp_stream.has_next()) {
583 const char* path = cp_stream.get_next();
584 struct stat st;
585 if (os::stat(path, &st) == 0) {
586 // File or directory found
587 ClassPathEntry* new_entry = create_class_path_entry(current, path, &st, false, false);
588 // If the path specification is valid, enter it into this module's list
589 if (new_entry != nullptr) {
590 module_cpl->add_to_list(new_entry);
591 }
592 }
593 }
594
595 // Record the module into the list of --patch-module entries only if
596 // valid ClassPathEntrys have been created
597 if (module_cpl->module_first_entry() != nullptr) {
598 _patch_mod_entries->push(module_cpl);
599 }
600 }
601 }
602
603 // Determine whether the module has been patched via the command-line
604 // option --patch-module
605 bool ClassLoader::is_in_patch_mod_entries(Symbol* module_name) {
606 if (_patch_mod_entries != nullptr && _patch_mod_entries->is_nonempty()) {
607 int table_len = _patch_mod_entries->length();
608 for (int i = 0; i < table_len; i++) {
609 ModuleClassPathList* patch_mod = _patch_mod_entries->at(i);
610 if (module_name->fast_compare(patch_mod->module_name()) == 0) {
611 return true;
612 }
613 }
614 }
615 return false;
616 }
617
618 // Set up the _jrt_entry if present and boot append path
619 void ClassLoader::setup_bootstrap_search_path_impl(JavaThread* current, const char *class_path) {
620 ResourceMark rm(current);
621 ClasspathStream cp_stream(class_path);
622 bool set_base_piece = true;
623
624 #if INCLUDE_CDS
625 if (CDSConfig::is_dumping_archive()) {
626 if (!Arguments::has_jimage()) {
627 vm_exit_during_initialization("CDS is not supported in exploded JDK build", nullptr);
628 }
629 }
630 #endif
631
632 while (cp_stream.has_next()) {
633 const char* path = cp_stream.get_next();
634
635 if (set_base_piece) {
636 // The first time through the bootstrap_search setup, it must be determined
637 // what the base or core piece of the boot loader search is. Either a java runtime
638 // image is present or this is an exploded module build situation.
639 assert(string_ends_with(path, MODULES_IMAGE_NAME) || string_ends_with(path, JAVA_BASE_NAME),
640 "Incorrect boot loader search path, no java runtime image or " JAVA_BASE_NAME " exploded build");
641 struct stat st;
642 if (os::stat(path, &st) == 0) {
643 // Directory found
644 if (JImage_file != nullptr) {
645 assert(Arguments::has_jimage(), "sanity check");
646 const char* canonical_path = get_canonical_path(path, current);
647 assert(canonical_path != nullptr, "canonical_path issue");
648
649 _jrt_entry = new ClassPathImageEntry(JImage_file, canonical_path);
650 assert(_jrt_entry != nullptr && _jrt_entry->is_modules_image(), "No java runtime image present");
651 assert(_jrt_entry->jimage() != nullptr, "No java runtime image");
652 } // else it's an exploded build.
653 } else {
654 // If path does not exist, exit
655 vm_exit_during_initialization("Unable to establish the boot loader search path", path);
656 }
657 set_base_piece = false;
658 } else {
659 // Every entry on the boot class path after the initial base piece,
660 // which is set by os::set_boot_path(), is considered an appended entry.
661 update_class_path_entry_list(current, path, /* check_for_duplicates */ false,
662 /* is_boot_append */ true, /* from_class_path_attr */ false);
663 }
664 }
665 }
666
667 // Gets the exploded path for the named module. The memory for the path
668 // is allocated on the C heap if `c_heap` is true otherwise in the resource area.
669 static const char* get_exploded_module_path(const char* module_name, bool c_heap) {
670 const char *home = Arguments::get_java_home();
671 const char file_sep = os::file_separator()[0];
672 // 10 represents the length of "modules" + 2 file separators + \0
673 size_t len = strlen(home) + strlen(module_name) + 10;
674 char *path = c_heap ? NEW_C_HEAP_ARRAY(char, len, mtModule) : NEW_RESOURCE_ARRAY(char, len);
675 jio_snprintf(path, len, "%s%cmodules%c%s", home, file_sep, file_sep, module_name);
676 return path;
677 }
678
679 // During an exploded modules build, each module defined to the boot loader
680 // will be added to the ClassLoader::_exploded_entries array.
681 void ClassLoader::add_to_exploded_build_list(JavaThread* current, Symbol* module_sym) {
682 assert(!ClassLoader::has_jrt_entry(), "Exploded build not applicable");
683 assert(_exploded_entries != nullptr, "_exploded_entries was not initialized");
684
685 // Find the module's symbol
686 ResourceMark rm(current);
687 const char *module_name = module_sym->as_C_string();
688 const char *path = get_exploded_module_path(module_name, false);
689
690 struct stat st;
691 if (os::stat(path, &st) == 0) {
692 // Directory found
693 ClassPathEntry* new_entry = create_class_path_entry(current, path, &st, false, false);
694
695 // If the path specification is valid, enter it into this module's list.
696 // There is no need to check for duplicate modules in the exploded entry list,
697 // since no two modules with the same name can be defined to the boot loader.
698 // This is checked at module definition time in Modules::define_module.
699 if (new_entry != nullptr) {
700 ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
701 module_cpl->add_to_list(new_entry);
702 {
703 MutexLocker ml(current, Module_lock);
704 _exploded_entries->push(module_cpl);
705 }
706 log_info(class, load)("path: %s", path);
707 }
708 }
709 }
710
711 jzfile* ClassLoader::open_zip_file(const char* canonical_path, char** error_msg, JavaThread* thread) {
712 // enable call to C land
713 ThreadToNativeFromVM ttn(thread);
714 HandleMark hm(thread);
715 return ZipLibrary::open(canonical_path, error_msg);
716 }
717
718 ClassPathEntry* ClassLoader::create_class_path_entry(JavaThread* current,
719 const char *path, const struct stat* st,
720 bool is_boot_append,
721 bool from_class_path_attr) {
722 ClassPathEntry* new_entry = nullptr;
723 if ((st->st_mode & S_IFMT) == S_IFREG) {
724 ResourceMark rm(current);
725 // Regular file, should be a zip file
726 // Canonicalized filename
727 const char* canonical_path = get_canonical_path(path, current);
728 if (canonical_path == nullptr) {
729 return nullptr;
730 }
731 char* error_msg = nullptr;
732 jzfile* zip = open_zip_file(canonical_path, &error_msg, current);
733 if (zip != nullptr && error_msg == nullptr) {
734 new_entry = new ClassPathZipEntry(zip, path, is_boot_append, from_class_path_attr);
735 } else {
736 #if INCLUDE_CDS
737 ClassLoaderExt::set_has_non_jar_in_classpath();
738 #endif
739 return nullptr;
740 }
741 log_info(class, path)("opened: %s", path);
742 log_info(class, load)("opened: %s", path);
743 } else {
744 // Directory
745 new_entry = new ClassPathDirEntry(path);
746 log_info(class, load)("path: %s", path);
747 }
748 return new_entry;
749 }
750
751
752 // Create a class path zip entry for a given path (return null if not found
753 // or zip/JAR file cannot be opened)
754 ClassPathZipEntry* ClassLoader::create_class_path_zip_entry(const char *path, bool is_boot_append) {
755 // check for a regular file
756 struct stat st;
757 if (os::stat(path, &st) == 0) {
758 if ((st.st_mode & S_IFMT) == S_IFREG) {
759 JavaThread* thread = JavaThread::current();
760 ResourceMark rm(thread);
761 const char* canonical_path = get_canonical_path(path, thread);
762 if (canonical_path != nullptr) {
763 char* error_msg = nullptr;
764 jzfile* zip = open_zip_file(canonical_path, &error_msg, thread);
765 if (zip != nullptr && error_msg == nullptr) {
766 // create using canonical path
767 return new ClassPathZipEntry(zip, canonical_path, is_boot_append, false);
768 }
769 }
770 }
771 }
772 return nullptr;
773 }
774
775 // The boot append entries are added with a lock, and read lock free.
776 void ClassLoader::add_to_boot_append_entries(ClassPathEntry *new_entry) {
777 if (new_entry != nullptr) {
778 MutexLocker ml(Bootclasspath_lock, Mutex::_no_safepoint_check_flag);
779 if (_last_append_entry == nullptr) {
780 _last_append_entry = new_entry;
781 assert(first_append_entry() == nullptr, "boot loader's append class path entry list not empty");
782 Atomic::release_store(&_first_append_entry_list, new_entry);
783 } else {
784 _last_append_entry->set_next(new_entry);
785 _last_append_entry = new_entry;
786 }
787 }
788 }
789
790 // Record the path entries specified in -cp during dump time. The recorded
791 // information will be used at runtime for loading the archived app classes.
792 //
793 // Note that at dump time, ClassLoader::_app_classpath_entries are NOT used for
794 // loading app classes. Instead, the app class are loaded by the
795 // jdk/internal/loader/ClassLoaders$AppClassLoader instance.
796 bool ClassLoader::add_to_app_classpath_entries(JavaThread* current,
797 ClassPathEntry* entry,
798 bool check_for_duplicates) {
799 #if INCLUDE_CDS
800 assert(entry != nullptr, "ClassPathEntry should not be nullptr");
801 ClassPathEntry* e = _app_classpath_entries;
802 if (check_for_duplicates) {
803 while (e != nullptr) {
804 if (strcmp(e->name(), entry->name()) == 0) {
805 // entry already exists
806 return false;
807 }
808 e = e->next();
809 }
810 }
811
812 // The entry does not exist, add to the list
813 if (_app_classpath_entries == nullptr) {
814 assert(_last_app_classpath_entry == nullptr, "Sanity");
815 _app_classpath_entries = _last_app_classpath_entry = entry;
816 } else {
817 _last_app_classpath_entry->set_next(entry);
818 _last_app_classpath_entry = entry;
819 }
820
821 if (entry->is_jar_file()) {
822 ClassLoaderExt::process_jar_manifest(current, entry);
823 }
824 #endif
825 return true;
826 }
827
828 // Returns true IFF the file/dir exists and the entry was successfully created.
829 bool ClassLoader::update_class_path_entry_list(JavaThread* current,
830 const char *path,
831 bool check_for_duplicates,
832 bool is_boot_append,
833 bool from_class_path_attr) {
834 struct stat st;
835 if (os::stat(path, &st) == 0) {
836 // File or directory found
837 ClassPathEntry* new_entry = nullptr;
838 new_entry = create_class_path_entry(current, path, &st, is_boot_append, from_class_path_attr);
839 if (new_entry == nullptr) {
840 return false;
841 }
842
843 // Do not reorder the bootclasspath which would break get_system_package().
844 // Add new entry to linked list
845 if (is_boot_append) {
846 add_to_boot_append_entries(new_entry);
847 } else {
848 if (!add_to_app_classpath_entries(current, new_entry, check_for_duplicates)) {
849 // new_entry is not saved, free it now
850 delete new_entry;
851 }
852 }
853 return true;
854 } else {
855 return false;
856 }
857 }
858
859 static void print_module_entry_table(const GrowableArray<ModuleClassPathList*>* const module_list) {
860 ResourceMark rm;
861 int num_of_entries = module_list->length();
862 for (int i = 0; i < num_of_entries; i++) {
863 ClassPathEntry* e;
864 ModuleClassPathList* mpl = module_list->at(i);
865 tty->print("%s=", mpl->module_name()->as_C_string());
866 e = mpl->module_first_entry();
867 while (e != nullptr) {
868 tty->print("%s", e->name());
869 e = e->next();
870 if (e != nullptr) {
871 tty->print("%s", os::path_separator());
872 }
873 }
874 tty->print(" ;");
875 }
876 }
877
878 void ClassLoader::print_bootclasspath() {
879 ClassPathEntry* e;
880 tty->print("[bootclasspath= ");
881
882 // Print --patch-module module/path specifications first
883 if (_patch_mod_entries != nullptr) {
884 print_module_entry_table(_patch_mod_entries);
885 }
886
887 // [jimage | exploded modules build]
888 if (has_jrt_entry()) {
889 // Print the location of the java runtime image
890 tty->print("%s ;", _jrt_entry->name());
891 } else {
892 // Print exploded module build path specifications
893 if (_exploded_entries != nullptr) {
894 print_module_entry_table(_exploded_entries);
895 }
896 }
897
898 // appended entries
899 e = first_append_entry();
900 while (e != nullptr) {
901 tty->print("%s ;", e->name());
902 e = e->next();
903 }
904 tty->print_cr("]");
905 }
906
907 void* ClassLoader::dll_lookup(void* lib, const char* name, const char* path) {
908 void* func = os::dll_lookup(lib, name);
909 if (func == nullptr) {
910 char msg[256] = "";
911 jio_snprintf(msg, sizeof(msg), "Could not resolve \"%s\"", name);
912 vm_exit_during_initialization(msg, path);
913 }
914 return func;
915 }
916
917 void ClassLoader::load_java_library() {
918 assert(CanonicalizeEntry == nullptr, "should not load java library twice");
919 void *javalib_handle = os::native_java_library();
920 if (javalib_handle == nullptr) {
921 vm_exit_during_initialization("Unable to load java library", nullptr);
922 }
923
924 CanonicalizeEntry = CAST_TO_FN_PTR(canonicalize_fn_t, dll_lookup(javalib_handle, "JDK_Canonicalize", nullptr));
925 }
926
927 void ClassLoader::load_jimage_library() {
928 assert(JImageOpen == nullptr, "should not load jimage library twice");
929 char path[JVM_MAXPATHLEN];
930 char ebuf[1024];
931 void* handle = nullptr;
932 if (os::dll_locate_lib(path, sizeof(path), Arguments::get_dll_dir(), "jimage")) {
933 handle = os::dll_load(path, ebuf, sizeof ebuf);
934 }
935 if (handle == nullptr) {
936 vm_exit_during_initialization("Unable to load jimage library", path);
937 }
938
939 JImageOpen = CAST_TO_FN_PTR(JImageOpen_t, dll_lookup(handle, "JIMAGE_Open", path));
940 JImageClose = CAST_TO_FN_PTR(JImageClose_t, dll_lookup(handle, "JIMAGE_Close", path));
941 JImageFindResource = CAST_TO_FN_PTR(JImageFindResource_t, dll_lookup(handle, "JIMAGE_FindResource", path));
942 JImageGetResource = CAST_TO_FN_PTR(JImageGetResource_t, dll_lookup(handle, "JIMAGE_GetResource", path));
943 }
944
945 int ClassLoader::crc32(int crc, const char* buf, int len) {
946 return ZipLibrary::crc32(crc, (const jbyte*)buf, len);
947 }
948
949 oop ClassLoader::get_system_package(const char* name, TRAPS) {
950 // Look up the name in the boot loader's package entry table.
951 if (name != nullptr) {
952 TempNewSymbol package_sym = SymbolTable::new_symbol(name);
953 // Look for the package entry in the boot loader's package entry table.
954 PackageEntry* package =
955 ClassLoaderData::the_null_class_loader_data()->packages()->lookup_only(package_sym);
956
957 // Return null if package does not exist or if no classes in that package
958 // have been loaded.
959 if (package != nullptr && package->has_loaded_class()) {
960 ModuleEntry* module = package->module();
961 if (module->location() != nullptr) {
962 ResourceMark rm(THREAD);
963 Handle ml = java_lang_String::create_from_str(
964 module->location()->as_C_string(), THREAD);
965 return ml();
966 }
967 // Return entry on boot loader class path.
968 Handle cph = java_lang_String::create_from_str(
969 ClassLoader::classpath_entry(package->classpath_index())->name(), THREAD);
970 return cph();
971 }
972 }
973 return nullptr;
974 }
975
976 objArrayOop ClassLoader::get_system_packages(TRAPS) {
977 ResourceMark rm(THREAD);
978 // List of pointers to PackageEntrys that have loaded classes.
979 PackageEntryTable* pe_table =
980 ClassLoaderData::the_null_class_loader_data()->packages();
981 GrowableArray<PackageEntry*>* loaded_class_pkgs = pe_table->get_system_packages();
982
983 // Allocate objArray and fill with java.lang.String
984 objArrayOop r = oopFactory::new_objArray(vmClasses::String_klass(),
985 loaded_class_pkgs->length(), CHECK_NULL);
986 objArrayHandle result(THREAD, r);
987 for (int x = 0; x < loaded_class_pkgs->length(); x++) {
988 PackageEntry* package_entry = loaded_class_pkgs->at(x);
989 Handle str = java_lang_String::create_from_symbol(package_entry->name(), CHECK_NULL);
990 result->obj_at_put(x, str());
991 }
992 return result();
993 }
994
995 // caller needs ResourceMark
996 const char* ClassLoader::file_name_for_class_name(const char* class_name,
997 int class_name_len) {
998 assert(class_name != nullptr, "invariant");
999 assert((int)strlen(class_name) == class_name_len, "invariant");
1000
1001 static const char class_suffix[] = ".class";
1002 size_t class_suffix_len = sizeof(class_suffix);
1003
1004 char* const file_name = NEW_RESOURCE_ARRAY(char,
1005 class_name_len +
1006 class_suffix_len); // includes term null
1007
1008 strncpy(file_name, class_name, class_name_len);
1009 strncpy(&file_name[class_name_len], class_suffix, class_suffix_len);
1010
1011 return file_name;
1012 }
1013
1014 static ClassPathEntry* find_first_module_cpe(ModuleEntry* mod_entry,
1015 const GrowableArray<ModuleClassPathList*>* const module_list) {
1016 int num_of_entries = module_list->length();
1017 const Symbol* class_module_name = mod_entry->name();
1018
1019 // Loop through all the modules in either the patch-module or exploded entries looking for module
1020 for (int i = 0; i < num_of_entries; i++) {
1021 ModuleClassPathList* module_cpl = module_list->at(i);
1022 Symbol* module_cpl_name = module_cpl->module_name();
1023
1024 if (module_cpl_name->fast_compare(class_module_name) == 0) {
1025 // Class' module has been located.
1026 return module_cpl->module_first_entry();
1027 }
1028 }
1029 return nullptr;
1030 }
1031
1032
1033 // Search either the patch-module or exploded build entries for class.
1034 ClassFileStream* ClassLoader::search_module_entries(JavaThread* current,
1035 const GrowableArray<ModuleClassPathList*>* const module_list,
1036 const char* const class_name,
1037 const char* const file_name) {
1038 ClassFileStream* stream = nullptr;
1039
1040 // Find the class' defining module in the boot loader's module entry table
1041 TempNewSymbol class_name_symbol = SymbolTable::new_symbol(class_name);
1042 TempNewSymbol pkg_name = package_from_class_name(class_name_symbol);
1043 PackageEntry* pkg_entry = get_package_entry(pkg_name, ClassLoaderData::the_null_class_loader_data());
1044 ModuleEntry* mod_entry = (pkg_entry != nullptr) ? pkg_entry->module() : nullptr;
1045
1046 // If the module system has not defined java.base yet, then
1047 // classes loaded are assumed to be defined to java.base.
1048 // When java.base is eventually defined by the module system,
1049 // all packages of classes that have been previously loaded
1050 // are verified in ModuleEntryTable::verify_javabase_packages().
1051 if (!Universe::is_module_initialized() &&
1052 !ModuleEntryTable::javabase_defined() &&
1053 mod_entry == nullptr) {
1054 mod_entry = ModuleEntryTable::javabase_moduleEntry();
1055 }
1056
1057 // The module must be a named module
1058 ClassPathEntry* e = nullptr;
1059 if (mod_entry != nullptr && mod_entry->is_named()) {
1060 if (module_list == _exploded_entries) {
1061 // The exploded build entries can be added to at any time so a lock is
1062 // needed when searching them.
1063 assert(!ClassLoader::has_jrt_entry(), "Must be exploded build");
1064 MutexLocker ml(current, Module_lock);
1065 e = find_first_module_cpe(mod_entry, module_list);
1066 } else {
1067 e = find_first_module_cpe(mod_entry, module_list);
1068 }
1069 }
1070
1071 // Try to load the class from the module's ClassPathEntry list.
1072 while (e != nullptr) {
1073 stream = e->open_stream(current, file_name);
1074 // No context.check is required since CDS is not supported
1075 // for an exploded modules build or if --patch-module is specified.
1076 if (nullptr != stream) {
1077 return stream;
1078 }
1079 e = e->next();
1080 }
1081 // If the module was located, break out even if the class was not
1082 // located successfully from that module's ClassPathEntry list.
1083 // There will not be another valid entry for that module.
1084 return nullptr;
1085 }
1086
1087 // Called by the boot classloader to load classes
1088 InstanceKlass* ClassLoader::load_class(Symbol* name, bool search_append_only, TRAPS) {
1089 assert(name != nullptr, "invariant");
1090
1091 ResourceMark rm(THREAD);
1092 HandleMark hm(THREAD);
1093
1094 const char* const class_name = name->as_C_string();
1095
1096 EventMarkClassLoading m("Loading class %s", class_name);
1097
1098 const char* const file_name = file_name_for_class_name(class_name,
1099 name->utf8_length());
1100 assert(file_name != nullptr, "invariant");
1101
1102 // Lookup stream for parsing .class file
1103 ClassFileStream* stream = nullptr;
1104 s2 classpath_index = 0;
1105 ClassPathEntry* e = nullptr;
1106 bool is_patched = false;
1107
1108 // If search_append_only is true, boot loader visibility boundaries are
1109 // set to be _first_append_entry to the end. This includes:
1110 // [-Xbootclasspath/a]; [jvmti appended entries]
1111 //
1112 // If search_append_only is false, boot loader visibility boundaries are
1113 // set to be the --patch-module entries plus the base piece. This includes:
1114 // [--patch-module=<module>=<file>(<pathsep><file>)*]; [jimage | exploded module build]
1115 //
1116
1117 // Load Attempt #1: --patch-module
1118 // Determine the class' defining module. If it appears in the _patch_mod_entries,
1119 // attempt to load the class from those locations specific to the module.
1120 // Specifications to --patch-module can contain a partial number of classes
1121 // that are part of the overall module definition. So if a particular class is not
1122 // found within its module specification, the search should continue to Load Attempt #2.
1123 // Note: The --patch-module entries are never searched if the boot loader's
1124 // visibility boundary is limited to only searching the append entries.
1125 if (_patch_mod_entries != nullptr && !search_append_only) {
1126 // At CDS dump time, the --patch-module entries are ignored. That means a
1127 // class is still loaded from the runtime image even if it might
1128 // appear in the _patch_mod_entries. The runtime shared class visibility
1129 // check will determine if a shared class is visible based on the runtime
1130 // environment, including the runtime --patch-module setting.
1131 if (!CDSConfig::is_valhalla_preview()) {
1132 // Dynamic dumping requires UseSharedSpaces to be enabled. Since --patch-module
1133 // is not supported with UseSharedSpaces, we can never come here during dynamic dumping.
1134 assert(!CDSConfig::is_dumping_dynamic_archive(), "sanity");
1135 }
1136 if (CDSConfig::is_valhalla_preview() || !CDSConfig::is_dumping_static_archive()) {
1137 stream = search_module_entries(THREAD, _patch_mod_entries, class_name, file_name);
1138 if (stream != nullptr) {
1139 is_patched = true;
1140 }
1141 }
1142 }
1143
1144 // Load Attempt #2: [jimage | exploded build]
1145 if (!search_append_only && (nullptr == stream)) {
1146 if (has_jrt_entry()) {
1147 e = _jrt_entry;
1148 stream = _jrt_entry->open_stream(THREAD, file_name);
1149 } else {
1150 // Exploded build - attempt to locate class in its defining module's location.
1151 assert(_exploded_entries != nullptr, "No exploded build entries present");
1152 stream = search_module_entries(THREAD, _exploded_entries, class_name, file_name);
1153 }
1154 }
1155
1156 // Load Attempt #3: [-Xbootclasspath/a]; [jvmti appended entries]
1157 if (search_append_only && (nullptr == stream)) {
1158 // For the boot loader append path search, the starting classpath_index
1159 // for the appended piece is always 1 to account for either the
1160 // _jrt_entry or the _exploded_entries.
1161 assert(classpath_index == 0, "The classpath_index has been incremented incorrectly");
1162 classpath_index = 1;
1163
1164 e = first_append_entry();
1165 while (e != nullptr) {
1166 stream = e->open_stream(THREAD, file_name);
1167 if (nullptr != stream) {
1168 break;
1169 }
1170 e = e->next();
1171 ++classpath_index;
1172 }
1173 }
1174
1175 if (nullptr == stream) {
1176 return nullptr;
1177 }
1178
1179 stream->set_verify(ClassLoaderExt::should_verify(classpath_index));
1180
1181 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
1182 Handle protection_domain;
1183 ClassLoadInfo cl_info(protection_domain);
1184
1185 InstanceKlass* result = KlassFactory::create_from_stream(stream,
1186 name,
1187 loader_data,
1188 cl_info,
1189 CHECK_NULL);
1190 result->set_classpath_index(classpath_index);
1191 if (is_patched) {
1192 result->set_shared_classpath_index(0);
1193 result->set_shared_class_loader_type(ClassLoader::BOOT_LOADER);
1194 }
1195 return result;
1196 }
1197
1198 #if INCLUDE_CDS
1199 char* ClassLoader::skip_uri_protocol(char* source) {
1200 if (strncmp(source, "file:", 5) == 0) {
1201 // file: protocol path could start with file:/ or file:///
1202 // locate the char after all the forward slashes
1203 int offset = 5;
1204 while (*(source + offset) == '/') {
1205 offset++;
1206 }
1207 source += offset;
1208 // for non-windows platforms, move back one char as the path begins with a '/'
1209 #ifndef _WINDOWS
1210 source -= 1;
1211 #endif
1212 } else if (strncmp(source, "jrt:/", 5) == 0) {
1213 source += 5;
1214 }
1215 return source;
1216 }
1217
1218 // Record the shared classpath index and loader type for classes loaded
1219 // by the builtin loaders at dump time.
1220 void ClassLoader::record_result(JavaThread* current, InstanceKlass* ik,
1221 const ClassFileStream* stream, bool redefined) {
1222 assert(CDSConfig::is_dumping_archive(), "sanity");
1223 assert(stream != nullptr, "sanity");
1224
1225 if (ik->is_hidden()) {
1226 // We do not archive hidden classes.
1227 return;
1228 }
1229
1230 if (ik->shared_classpath_index() == 0 && ik->is_shared_boot_class()) {
1231 return;
1232 }
1233
1234 oop loader = ik->class_loader();
1235 char* src = (char*)stream->source();
1236 if (src == nullptr) {
1237 if (loader == nullptr) {
1238 // JFR classes
1239 ik->set_shared_classpath_index(0);
1240 ik->set_shared_class_loader_type(ClassLoader::BOOT_LOADER);
1241 }
1242 return;
1243 }
1244
1245 assert(has_jrt_entry(), "CDS dumping does not support exploded JDK build");
1246
1247 ResourceMark rm(current);
1248 int classpath_index = -1;
1249 PackageEntry* pkg_entry = ik->package();
1250
1251 if (FileMapInfo::get_number_of_shared_paths() > 0) {
1252 // Save the path from the file: protocol or the module name from the jrt: protocol
1253 // if no protocol prefix is found, path is the same as stream->source(). This path
1254 // must be valid since the class has been successfully parsed.
1255 char* path = skip_uri_protocol(src);
1256 assert(path != nullptr, "sanity");
1257 for (int i = 0; i < FileMapInfo::get_number_of_shared_paths(); i++) {
1258 SharedClassPathEntry* ent = FileMapInfo::shared_path(i);
1259 // A shared path has been validated during its creation in ClassLoader::create_class_path_entry(),
1260 // it must be valid here.
1261 assert(ent->name() != nullptr, "sanity");
1262 // If the path (from the class stream source) is the same as the shared
1263 // class or module path, then we have a match.
1264 // src may come from the App/Platform class loaders, which would canonicalize
1265 // the file name. We cannot use strcmp to check for equality against ent->name().
1266 // We must use os::same_files (which is faster than canonicalizing ent->name()).
1267 if (os::same_files(ent->name(), path)) {
1268 // null pkg_entry and pkg_entry in an unnamed module implies the class
1269 // is from the -cp or boot loader append path which consists of -Xbootclasspath/a
1270 // and jvmti appended entries.
1271 if ((pkg_entry == nullptr) || (pkg_entry->in_unnamed_module())) {
1272 // Ensure the index is within the -cp range before assigning
1273 // to the classpath_index.
1274 if (SystemDictionary::is_system_class_loader(loader) &&
1275 (i >= ClassLoaderExt::app_class_paths_start_index()) &&
1276 (i < ClassLoaderExt::app_module_paths_start_index())) {
1277 classpath_index = i;
1278 break;
1279 } else {
1280 if ((i >= 1) &&
1281 (i < ClassLoaderExt::app_class_paths_start_index())) {
1282 // The class must be from boot loader append path which consists of
1283 // -Xbootclasspath/a and jvmti appended entries.
1284 assert(loader == nullptr, "sanity");
1285 classpath_index = i;
1286 break;
1287 }
1288 }
1289 } else {
1290 // A class from a named module from the --module-path. Ensure the index is
1291 // within the --module-path range before assigning to the classpath_index.
1292 if ((pkg_entry != nullptr) && !(pkg_entry->in_unnamed_module()) && (i > 0)) {
1293 if (i >= ClassLoaderExt::app_module_paths_start_index() &&
1294 i < FileMapInfo::get_number_of_shared_paths()) {
1295 classpath_index = i;
1296 break;
1297 }
1298 }
1299 }
1300 }
1301 // for index 0 and the stream->source() is the modules image or has the jrt: protocol.
1302 // The class must be from the runtime modules image.
1303 if (i == 0 && (stream->from_boot_loader_modules_image() || string_starts_with(src, "jrt:"))) {
1304 classpath_index = i;
1305 break;
1306 }
1307 }
1308
1309 // No path entry found for this class: most likely a shared class loaded by the
1310 // user defined classloader.
1311 if (classpath_index < 0 && !SystemDictionaryShared::is_builtin_loader(ik->class_loader_data())) {
1312 assert(ik->shared_classpath_index() < 0, "not assigned yet");
1313 ik->set_shared_classpath_index(UNREGISTERED_INDEX);
1314 SystemDictionaryShared::set_shared_class_misc_info(ik, (ClassFileStream*)stream);
1315 return;
1316 }
1317 } else {
1318 // The shared path table is set up after module system initialization.
1319 // The path table contains no entry before that. Any classes loaded prior
1320 // to the setup of the shared path table must be from the modules image.
1321 if (!CDSConfig::is_valhalla_preview()) {
1322 assert(stream->from_boot_loader_modules_image(), "stream must be loaded by boot loader from modules image");
1323 }
1324 assert(FileMapInfo::get_number_of_shared_paths() == 0, "shared path table must not have been setup");
1325 classpath_index = 0;
1326 }
1327
1328 const char* const class_name = ik->name()->as_C_string();
1329 const char* const file_name = file_name_for_class_name(class_name,
1330 ik->name()->utf8_length());
1331 assert(file_name != nullptr, "invariant");
1332 ClassLoaderExt::record_result(checked_cast<s2>(classpath_index), ik, redefined);
1333 }
1334 #endif // INCLUDE_CDS
1335
1336 // Initialize the class loader's access to methods in libzip. Parse and
1337 // process the boot classpath into a list ClassPathEntry objects. Once
1338 // this list has been created, it must not change order (see class PackageInfo)
1339 // it can be appended to and is by jvmti.
1340
1341 void ClassLoader::initialize(TRAPS) {
1342 if (UsePerfData) {
1343 // jvmstat performance counters
1344 NEWPERFTICKCOUNTER(_perf_accumulated_time, SUN_CLS, "time");
1345 NEWPERFTICKCOUNTER(_perf_class_init_time, SUN_CLS, "classInitTime");
1346 NEWPERFTICKCOUNTER(_perf_class_init_selftime, SUN_CLS, "classInitTime.self");
1347 NEWPERFTICKCOUNTER(_perf_class_verify_time, SUN_CLS, "classVerifyTime");
1348 NEWPERFTICKCOUNTER(_perf_class_verify_selftime, SUN_CLS, "classVerifyTime.self");
1349 NEWPERFTICKCOUNTER(_perf_class_link_time, SUN_CLS, "classLinkedTime");
1350 NEWPERFTICKCOUNTER(_perf_class_link_selftime, SUN_CLS, "classLinkedTime.self");
1351 NEWPERFEVENTCOUNTER(_perf_classes_inited, SUN_CLS, "initializedClasses");
1352 NEWPERFEVENTCOUNTER(_perf_classes_linked, SUN_CLS, "linkedClasses");
1353 NEWPERFEVENTCOUNTER(_perf_classes_verified, SUN_CLS, "verifiedClasses");
1354
1355 NEWPERFTICKCOUNTER(_perf_shared_classload_time, SUN_CLS, "sharedClassLoadTime");
1356 NEWPERFTICKCOUNTER(_perf_sys_classload_time, SUN_CLS, "sysClassLoadTime");
1357 NEWPERFTICKCOUNTER(_perf_app_classload_time, SUN_CLS, "appClassLoadTime");
1358 NEWPERFTICKCOUNTER(_perf_app_classload_selftime, SUN_CLS, "appClassLoadTime.self");
1359 NEWPERFEVENTCOUNTER(_perf_app_classload_count, SUN_CLS, "appClassLoadCount");
1360 NEWPERFTICKCOUNTER(_perf_define_appclasses, SUN_CLS, "defineAppClasses");
1361 NEWPERFTICKCOUNTER(_perf_define_appclass_time, SUN_CLS, "defineAppClassTime");
1362 NEWPERFTICKCOUNTER(_perf_define_appclass_selftime, SUN_CLS, "defineAppClassTime.self");
1363 NEWPERFBYTECOUNTER(_perf_app_classfile_bytes_read, SUN_CLS, "appClassBytes");
1364 NEWPERFBYTECOUNTER(_perf_sys_classfile_bytes_read, SUN_CLS, "sysClassBytes");
1365
1366 NEWPERFEVENTCOUNTER(_unsafe_defineClassCallCounter, SUN_CLS, "unsafeDefineClassCalls");
1367 }
1368
1369 // lookup java library entry points
1370 load_java_library();
1371 // jimage library entry points are loaded below, in lookup_vm_options
1372 setup_bootstrap_search_path(THREAD);
1373 }
1374
1375 static char* lookup_vm_resource(JImageFile *jimage, const char *jimage_version, const char *path) {
1376 jlong size;
1377 JImageLocationRef location = (*JImageFindResource)(jimage, "java.base", jimage_version, path, &size);
1378 if (location == 0)
1379 return nullptr;
1380 char *val = NEW_C_HEAP_ARRAY(char, size+1, mtClass);
1381 (*JImageGetResource)(jimage, location, val, size);
1382 val[size] = '\0';
1383 return val;
1384 }
1385
1386 // Lookup VM options embedded in the modules jimage file
1387 char* ClassLoader::lookup_vm_options() {
1388 jint error;
1389 char modules_path[JVM_MAXPATHLEN];
1390 const char* fileSep = os::file_separator();
1391
1392 // Initialize jimage library entry points
1393 load_jimage_library();
1394
1395 jio_snprintf(modules_path, JVM_MAXPATHLEN, "%s%slib%smodules", Arguments::get_java_home(), fileSep, fileSep);
1396 JImage_file =(*JImageOpen)(modules_path, &error);
1397 if (JImage_file == nullptr) {
1398 return nullptr;
1399 }
1400
1401 const char *jimage_version = get_jimage_version_string();
1402 char *options = lookup_vm_resource(JImage_file, jimage_version, "jdk/internal/vm/options");
1403 return options;
1404 }
1405
1406 bool ClassLoader::is_module_observable(const char* module_name) {
1407 assert(JImageOpen != nullptr, "jimage library should have been opened");
1408 if (JImage_file == nullptr) {
1409 struct stat st;
1410 const char *path = get_exploded_module_path(module_name, true);
1411 bool res = os::stat(path, &st) == 0;
1412 FREE_C_HEAP_ARRAY(char, path);
1413 return res;
1414 }
1415 jlong size;
1416 const char *jimage_version = get_jimage_version_string();
1417 return (*JImageFindResource)(JImage_file, module_name, jimage_version, "module-info.class", &size) != 0;
1418 }
1419
1420 #if INCLUDE_CDS
1421 void ClassLoader::initialize_shared_path(JavaThread* current) {
1422 if (CDSConfig::is_dumping_archive()) {
1423 ClassLoaderExt::setup_search_paths(current);
1424 }
1425 }
1426
1427 void ClassLoader::initialize_module_path(TRAPS) {
1428 if (CDSConfig::is_dumping_archive()) {
1429 ClassLoaderExt::setup_module_paths(THREAD);
1430 FileMapInfo::allocate_shared_path_table(CHECK);
1431 }
1432 }
1433
1434 // Helper function used by CDS code to get the number of module path
1435 // entries during shared classpath setup time.
1436 int ClassLoader::num_module_path_entries() {
1437 assert(CDSConfig::is_dumping_archive(), "sanity");
1438 int num_entries = 0;
1439 ClassPathEntry* e= ClassLoader::_module_path_entries;
1440 while (e != nullptr) {
1441 num_entries ++;
1442 e = e->next();
1443 }
1444 return num_entries;
1445 }
1446 #endif
1447
1448 jlong ClassLoader::classloader_time_ms() {
1449 return UsePerfData ?
1450 Management::ticks_to_ms(_perf_accumulated_time->get_value()) : -1;
1451 }
1452
1453 jlong ClassLoader::class_init_count() {
1454 return UsePerfData ? _perf_classes_inited->get_value() : -1;
1455 }
1456
1457 jlong ClassLoader::class_init_time_ms() {
1458 return UsePerfData ?
1459 Management::ticks_to_ms(_perf_class_init_time->get_value()) : -1;
1460 }
1461
1462 jlong ClassLoader::class_verify_time_ms() {
1463 return UsePerfData ?
1464 Management::ticks_to_ms(_perf_class_verify_time->get_value()) : -1;
1465 }
1466
1467 jlong ClassLoader::class_link_count() {
1468 return UsePerfData ? _perf_classes_linked->get_value() : -1;
1469 }
1470
1471 jlong ClassLoader::class_link_time_ms() {
1472 return UsePerfData ?
1473 Management::ticks_to_ms(_perf_class_link_time->get_value()) : -1;
1474 }
1475
1476 int ClassLoader::compute_Object_vtable() {
1477 // hardwired for JDK1.2 -- would need to duplicate class file parsing
1478 // code to determine actual value from file
1479 // Would be value '11' if finals were in vtable
1480 int JDK_1_2_Object_vtable_size = 5;
1481 return JDK_1_2_Object_vtable_size * vtableEntry::size();
1482 }
1483
1484
1485 void classLoader_init1() {
1486 EXCEPTION_MARK;
1487 ClassLoader::initialize(THREAD);
1488 if (HAS_PENDING_EXCEPTION) {
1489 vm_exit_during_initialization("ClassLoader::initialize() failed unexpectedly");
1490 }
1491 }
1492
1493 // Complete the ClassPathEntry setup for the boot loader
1494 void ClassLoader::classLoader_init2(JavaThread* current) {
1495 // Setup the list of module/path pairs for --patch-module processing
1496 // This must be done after the SymbolTable is created in order
1497 // to use fast_compare on module names instead of a string compare.
1498 if (Arguments::get_patch_mod_prefix() != nullptr) {
1499 setup_patch_mod_entries();
1500 }
1501
1502 // Create the ModuleEntry for java.base (must occur after setup_patch_mod_entries
1503 // to successfully determine if java.base has been patched)
1504 create_javabase();
1505
1506 // Setup the initial java.base/path pair for the exploded build entries.
1507 // As more modules are defined during module system initialization, more
1508 // entries will be added to the exploded build array.
1509 if (!has_jrt_entry()) {
1510 assert(!CDSConfig::is_dumping_archive(), "not supported with exploded module builds");
1511 assert(!UseSharedSpaces, "UsedSharedSpaces not supported with exploded module builds");
1512 // Set up the boot loader's _exploded_entries list. Note that this gets
1513 // done before loading any classes, by the same thread that will
1514 // subsequently do the first class load. So, no lock is needed for this.
1515 assert(_exploded_entries == nullptr, "Should only get initialized once");
1516 _exploded_entries = new (mtModule)
1517 GrowableArray<ModuleClassPathList*>(EXPLODED_ENTRY_SIZE, mtModule);
1518 add_to_exploded_build_list(current, vmSymbols::java_base());
1519 }
1520 }
1521
1522 char* ClassLoader::get_canonical_path(const char* orig, Thread* thread) {
1523 assert(orig != nullptr, "bad arguments");
1524 // caller needs to allocate ResourceMark for the following output buffer
1525 char* canonical_path = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, JVM_MAXPATHLEN);
1526 ResourceMark rm(thread);
1527 // os::native_path writes into orig_copy
1528 char* orig_copy = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, strlen(orig)+1);
1529 strcpy(orig_copy, orig);
1530 if ((CanonicalizeEntry)(os::native_path(orig_copy), canonical_path, JVM_MAXPATHLEN) < 0) {
1531 return nullptr;
1532 }
1533 return canonical_path;
1534 }
1535
1536 void ClassLoader::create_javabase() {
1537 JavaThread* current = JavaThread::current();
1538
1539 // Create java.base's module entry for the boot
1540 // class loader prior to loading j.l.Object.
1541 ClassLoaderData* null_cld = ClassLoaderData::the_null_class_loader_data();
1542
1543 // Get module entry table
1544 ModuleEntryTable* null_cld_modules = null_cld->modules();
1545 if (null_cld_modules == nullptr) {
1546 vm_exit_during_initialization("No ModuleEntryTable for the boot class loader");
1547 }
1548
1549 {
1550 MutexLocker ml(current, Module_lock);
1551 if (ModuleEntryTable::javabase_moduleEntry() == nullptr) { // may have been inited by CDS.
1552 ModuleEntry* jb_module = null_cld_modules->locked_create_entry(Handle(),
1553 false, vmSymbols::java_base(), nullptr, nullptr, null_cld);
1554 if (jb_module == nullptr) {
1555 vm_exit_during_initialization("Unable to create ModuleEntry for " JAVA_BASE_NAME);
1556 }
1557 ModuleEntryTable::set_javabase_moduleEntry(jb_module);
1558 }
1559 }
1560 }
1561
1562 // Please keep following two functions at end of this file. With them placed at top or in middle of the file,
1563 // they could get inlined by aggressive compiler, an unknown trick, see bug 6966589.
1564 void PerfClassTraceTime::initialize() {
1565 if (!UsePerfData) return;
1566
1567 if (_eventp != nullptr) {
1568 // increment the event counter
1569 _eventp->inc();
1570 }
1571
1572 // stop the current active thread-local timer to measure inclusive time
1573 _prev_active_event = -1;
1574 for (int i=0; i < EVENT_TYPE_COUNT; i++) {
1575 if (_timers[i].is_active()) {
1576 assert(_prev_active_event == -1, "should have only one active timer");
1577 _prev_active_event = i;
1578 _timers[i].stop();
1579 }
1580 }
1581
1582 if (_recursion_counters == nullptr || (_recursion_counters[_event_type])++ == 0) {
1583 // start the inclusive timer if not recursively called
1584 _t.start();
1585 }
1586
1587 // start thread-local timer of the given event type
1588 if (!_timers[_event_type].is_active()) {
1589 _timers[_event_type].start();
1590 }
1591 }
1592
1593 PerfClassTraceTime::~PerfClassTraceTime() {
1594 if (!UsePerfData) return;
1595
1596 // stop the thread-local timer as the event completes
1597 // and resume the thread-local timer of the event next on the stack
1598 _timers[_event_type].stop();
1599 jlong selftime = _timers[_event_type].ticks();
1600
1601 if (_prev_active_event >= 0) {
1602 _timers[_prev_active_event].start();
1603 }
1604
1605 if (_recursion_counters != nullptr && --(_recursion_counters[_event_type]) > 0) return;
1606
1607 // increment the counters only on the leaf call
1608 _t.stop();
1609 _timep->inc(_t.ticks());
1610 if (_selftimep != nullptr) {
1611 _selftimep->inc(selftime);
1612 }
1613 // add all class loading related event selftime to the accumulated time counter
1614 ClassLoader::perf_accumulated_time()->inc(selftime);
1615
1616 // reset the timer
1617 _timers[_event_type].reset();
1618 }