1 /*
2 * Copyright (c) 1997, 2026, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "cds/aotClassLocation.hpp"
26 #include "cds/cds_globals.hpp"
27 #include "cds/cdsConfig.hpp"
28 #include "cds/dynamicArchive.hpp"
29 #include "cds/heapShared.hpp"
30 #include "classfile/classFileStream.hpp"
31 #include "classfile/classLoader.inline.hpp"
32 #include "classfile/classLoaderData.inline.hpp"
33 #include "classfile/classLoadInfo.hpp"
34 #include "classfile/javaClasses.hpp"
35 #include "classfile/klassFactory.hpp"
36 #include "classfile/moduleEntry.hpp"
37 #include "classfile/modules.hpp"
38 #include "classfile/packageEntry.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 "cppstdlib/cstdlib.hpp"
46 #include "interpreter/bytecodeStream.hpp"
47 #include "interpreter/oopMapCache.hpp"
48 #include "jimage.hpp"
49 #include "jvm.h"
50 #include "logging/log.hpp"
51 #include "logging/logStream.hpp"
52 #include "logging/logTag.hpp"
53 #include "memory/allocation.inline.hpp"
54 #include "memory/oopFactory.hpp"
55 #include "memory/resourceArea.hpp"
56 #include "memory/universe.hpp"
57 #include "oops/instanceKlass.hpp"
58 #include "oops/instanceRefKlass.hpp"
59 #include "oops/klass.inline.hpp"
60 #include "oops/method.inline.hpp"
61 #include "oops/objArrayOop.inline.hpp"
62 #include "oops/oop.inline.hpp"
63 #include "oops/symbol.hpp"
64 #include "prims/jvm_misc.hpp"
65 #include "runtime/arguments.hpp"
66 #include "runtime/handles.inline.hpp"
67 #include "runtime/init.hpp"
68 #include "runtime/interfaceSupport.inline.hpp"
69 #include "runtime/java.hpp"
70 #include "runtime/javaCalls.hpp"
71 #include "runtime/os.hpp"
72 #include "runtime/perfData.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/ostream.hpp"
82 #include "utilities/utf8.hpp"
83
84 #include <ctype.h>
85
86 // Entry point in java.dll for path canonicalization
87
88 typedef int (*canonicalize_fn_t)(const char *orig, char *out, int len);
89
90 static canonicalize_fn_t CanonicalizeEntry = nullptr;
91
92 // Entry points for jimage.dll for loading jimage file entries
93
94 static JImageOpen_t JImageOpen = nullptr;
95 static JImageClose_t JImageClose = nullptr;
96 static JImageFindResource_t JImageFindResource = nullptr;
97 static JImageGetResource_t JImageGetResource = nullptr;
98
99 // JImageFile pointer, or null if exploded JDK build.
100 static JImageFile* JImage_file = nullptr;
101
102 // PreviewMode status to control preview behaviour. JImage_file is unusable
103 // for normal lookup until (Preview_mode != PREVIEW_MODE_UNINITIALIZED).
104 enum PreviewMode {
105 PREVIEW_MODE_UNINITIALIZED = 0,
106 PREVIEW_MODE_DEFAULT = 1,
107 PREVIEW_MODE_ENABLE_PREVIEW = 2
108 };
109 static PreviewMode Preview_mode = PREVIEW_MODE_UNINITIALIZED;
110
111 // Globals
112
113 PerfCounter* ClassLoader::_perf_accumulated_time = nullptr;
114 PerfCounter* ClassLoader::_perf_classes_inited = nullptr;
115 PerfCounter* ClassLoader::_perf_class_init_time = nullptr;
116 PerfCounter* ClassLoader::_perf_class_init_selftime = nullptr;
117 PerfCounter* ClassLoader::_perf_classes_verified = nullptr;
118 PerfCounter* ClassLoader::_perf_class_verify_time = nullptr;
119 PerfCounter* ClassLoader::_perf_class_verify_selftime = nullptr;
120 PerfCounter* ClassLoader::_perf_classes_linked = nullptr;
121 PerfCounter* ClassLoader::_perf_class_link_time = nullptr;
122 PerfCounter* ClassLoader::_perf_class_link_selftime = nullptr;
123 PerfCounter* ClassLoader::_perf_shared_classload_time = nullptr;
124 PerfCounter* ClassLoader::_perf_sys_classload_time = nullptr;
125 PerfCounter* ClassLoader::_perf_app_classload_time = nullptr;
126 PerfCounter* ClassLoader::_perf_app_classload_selftime = nullptr;
127 PerfCounter* ClassLoader::_perf_app_classload_count = nullptr;
128 PerfCounter* ClassLoader::_perf_define_appclasses = nullptr;
129 PerfCounter* ClassLoader::_perf_define_appclass_time = nullptr;
130 PerfCounter* ClassLoader::_perf_define_appclass_selftime = nullptr;
131 PerfCounter* ClassLoader::_perf_app_classfile_bytes_read = nullptr;
132 PerfCounter* ClassLoader::_perf_sys_classfile_bytes_read = nullptr;
133 PerfCounter* ClassLoader::_perf_ik_link_methods_time = nullptr;
134 PerfCounter* ClassLoader::_perf_method_adapters_time = nullptr;
135 PerfCounter* ClassLoader::_perf_ik_link_methods_count = nullptr;
136 PerfCounter* ClassLoader::_perf_method_adapters_count = nullptr;
137 PerfCounter* ClassLoader::_unsafe_defineClassCallCounter = nullptr;
138 PerfCounter* ClassLoader::_perf_secondary_hash_time = nullptr;
139 PerfCounter* ClassLoader::_perf_change_wx_time = nullptr;
140
141 PerfCounter* ClassLoader::_perf_resolve_indy_time = nullptr;
142 PerfCounter* ClassLoader::_perf_resolve_invokehandle_time = nullptr;
143 PerfCounter* ClassLoader::_perf_resolve_mh_time = nullptr;
144 PerfCounter* ClassLoader::_perf_resolve_mt_time = nullptr;
145
146 PerfCounter* ClassLoader::_perf_resolve_indy_count = nullptr;
147 PerfCounter* ClassLoader::_perf_resolve_invokehandle_count = nullptr;
148 PerfCounter* ClassLoader::_perf_resolve_mh_count = nullptr;
149 PerfCounter* ClassLoader::_perf_resolve_mt_count = nullptr;
150
151 void ClassLoader::print_counters(outputStream *st) {
152 st->print_cr("ClassLoader:");
153 st->print_cr(" clinit: " JLONG_FORMAT "ms / " JLONG_FORMAT " events", ClassLoader::class_init_time_ms(), ClassLoader::class_init_count());
154 st->print_cr(" link methods: " JLONG_FORMAT "ms / " JLONG_FORMAT " events", Management::ticks_to_ms(_perf_ik_link_methods_time->get_value()) , _perf_ik_link_methods_count->get_value());
155 st->print_cr(" method adapters: " JLONG_FORMAT "ms / " JLONG_FORMAT " events", Management::ticks_to_ms(_perf_method_adapters_time->get_value()) , _perf_method_adapters_count->get_value());
156 st->print_cr(" resolve...");
157 st->print_cr(" invokedynamic: " JLONG_FORMAT "ms / " JLONG_FORMAT " events", Management::ticks_to_ms(_perf_resolve_indy_time->get_value()) , _perf_resolve_indy_count->get_value());
158 st->print_cr(" invokehandle: " JLONG_FORMAT "ms / " JLONG_FORMAT " events", Management::ticks_to_ms(_perf_resolve_invokehandle_time->get_value()) , _perf_resolve_invokehandle_count->get_value());
159 st->print_cr(" CP_MethodHandle: " JLONG_FORMAT "ms / " JLONG_FORMAT " events", Management::ticks_to_ms(_perf_resolve_mh_time->get_value()) , _perf_resolve_mh_count->get_value());
160 st->print_cr(" CP_MethodType: " JLONG_FORMAT "ms / " JLONG_FORMAT " events", Management::ticks_to_ms(_perf_resolve_mt_time->get_value()) , _perf_resolve_mt_count->get_value());
161 st->cr();
162 }
163
164 GrowableArray<ModuleClassPathList*>* ClassLoader::_patch_mod_entries = nullptr;
165 GrowableArray<ModuleClassPathList*>* ClassLoader::_exploded_entries = nullptr;
166 ClassPathImageEntry* ClassLoader::_jrt_entry = nullptr;
167
168 ClassPathEntry* volatile ClassLoader::_first_append_entry_list = nullptr;
169 ClassPathEntry* volatile ClassLoader::_last_append_entry = nullptr;
170
171 // helper routines
172 #if INCLUDE_CDS
173 static bool string_starts_with(const char* str, const char* str_to_find) {
174 size_t str_len = strlen(str);
175 size_t str_to_find_len = strlen(str_to_find);
176 if (str_to_find_len > str_len) {
177 return false;
178 }
179 return (strncmp(str, str_to_find, str_to_find_len) == 0);
180 }
181 #endif
182
183 bool ClassLoader::string_ends_with(const char* str, const char* str_to_find) {
184 size_t str_len = strlen(str);
185 size_t str_to_find_len = strlen(str_to_find);
186 if (str_to_find_len > str_len) {
187 return false;
188 }
189 return (strncmp(str + (str_len - str_to_find_len), str_to_find, str_to_find_len) == 0);
190 }
191
192 // Used to obtain the package name from a fully qualified class name.
193 Symbol* ClassLoader::package_from_class_name(const Symbol* name, bool* bad_class_name) {
194 if (name == nullptr) {
195 if (bad_class_name != nullptr) {
196 *bad_class_name = true;
197 }
198 return nullptr;
199 }
200
201 int utf_len = name->utf8_length();
202 const jbyte* base = (const jbyte*)name->base();
203 const jbyte* start = base;
204 const jbyte* end = UTF8::strrchr(start, utf_len, JVM_SIGNATURE_SLASH);
205 if (end == nullptr) {
206 return nullptr;
207 }
208 // Skip over '['s
209 if (*start == JVM_SIGNATURE_ARRAY) {
210 do {
211 start++;
212 } while (start < end && *start == JVM_SIGNATURE_ARRAY);
213
214 // Fully qualified class names should not contain a 'L'.
215 // Set bad_class_name to true to indicate that the package name
216 // could not be obtained due to an error condition.
217 // In this situation, is_same_class_package returns false.
218 if (*start == JVM_SIGNATURE_CLASS) {
219 if (bad_class_name != nullptr) {
220 *bad_class_name = true;
221 }
222 return nullptr;
223 }
224 }
225 // A class name could have just the slash character in the name,
226 // in which case start > end
227 if (start >= end) {
228 // No package name
229 if (bad_class_name != nullptr) {
230 *bad_class_name = true;
231 }
232 return nullptr;
233 }
234 return SymbolTable::new_symbol(name, pointer_delta_as_int(start, base), pointer_delta_as_int(end, base));
235 }
236
237 // --------------------------------
238 // The following jimage_xxx static functions encapsulate all JImage_file and Preview_mode access.
239 // This is done to make it easy to reason about the JImage file state (exists vs initialized etc.).
240
241 // Opens the named JImage file and sets the JImage file reference.
242 // Returns true if opening the JImage file was successful (see also jimage_is_open()).
243 static bool jimage_open(const char* modules_path) {
244 // Currently 'error' is not set to anything useful, so ignore it here.
245 jint error;
246 JImage_file = (*JImageOpen)(modules_path, &error);
247 if (Arguments::has_jimage() && JImage_file == nullptr) {
248 // The modules file exists but is unreadable or corrupt
249 vm_exit_during_initialization(err_msg("Unable to load %s", modules_path));
250 }
251 return JImage_file != nullptr;
252 }
253
254 // Closes and clears the JImage file reference (this will only be called during shutdown).
255 static void jimage_close() {
256 if (JImage_file != nullptr) {
257 (*JImageClose)(JImage_file);
258 JImage_file = nullptr;
259 }
260 }
261
262 // Returns whether a JImage file was opened (but NOT whether it was initialized yet).
263 static bool jimage_is_open() {
264 return JImage_file != nullptr;
265 }
266
267 // Returns the JImage file reference (which may or may not be initialized).
268 static JImageFile* jimage_non_null() {
269 assert(jimage_is_open(), "should have been opened by ClassLoader::lookup_vm_options "
270 "and remains open throughout normal JVM lifetime");
271 return JImage_file;
272 }
273
274 // Returns true if jimage_init() has been called. Once the JImage file is initialized,
275 // jimage_is_preview_enabled() can be called to correctly determine the access mode.
276 static bool jimage_is_initialized() {
277 return jimage_is_open() && Preview_mode != PREVIEW_MODE_UNINITIALIZED;
278 }
279
280 // Returns the access mode for an initialized JImage file (reflects --enable-preview).
281 static bool is_preview_enabled() {
282 return Preview_mode == PREVIEW_MODE_ENABLE_PREVIEW;
283 }
284
285 // Looks up the location of a named JImage resource. This "raw" lookup function allows
286 // the preview mode to be manually specified, so must not be accessible outside this
287 // class. ClassPathImageEntry manages all calls for resources after startup is complete.
288 static JImageLocationRef jimage_find_resource(const char* module_name,
289 const char* file_name,
290 bool is_preview,
291 jlong* size) {
292 return ((*JImageFindResource)(jimage_non_null(),
293 module_name,
294 file_name,
295 is_preview,
296 size));
297 }
298 // --------------------------------
299
300 // Given a fully qualified package name, find its defining package in the class loader's
301 // package entry table.
302 PackageEntry* ClassLoader::get_package_entry(Symbol* pkg_name, ClassLoaderData* loader_data) {
303 if (pkg_name == nullptr) {
304 return nullptr;
305 }
306 PackageEntryTable* pkgEntryTable = loader_data->packages();
307 return pkgEntryTable->lookup_only(pkg_name);
308 }
309
310 const char* ClassPathEntry::copy_path(const char* path) {
311 char* copy = NEW_C_HEAP_ARRAY(char, strlen(path)+1, mtClass);
312 strcpy(copy, path);
313 return copy;
314 }
315
316 ClassPathDirEntry::~ClassPathDirEntry() {
317 FREE_C_HEAP_ARRAY(_dir);
318 }
319
320 ClassFileStream* ClassPathDirEntry::open_stream(JavaThread* current, const char* name) {
321 // construct full path name
322 assert((_dir != nullptr) && (name != nullptr), "sanity");
323 size_t path_len = strlen(_dir) + strlen(name) + strlen(os::file_separator()) + 1;
324 char* path = NEW_RESOURCE_ARRAY_IN_THREAD(current, char, path_len);
325 int len = jio_snprintf(path, path_len, "%s%s%s", _dir, os::file_separator(), name);
326 assert(len == (int)(path_len - 1), "sanity");
327 // check if file exists
328 struct stat st;
329 if (os::stat(path, &st) == 0) {
330 // found file, open it
331 int file_handle = os::open(path, 0, 0);
332 if (file_handle != -1) {
333 // read contents into resource array
334 u1* buffer = NEW_RESOURCE_ARRAY_IN_THREAD(current, u1, st.st_size);
335 size_t num_read = ::read(file_handle, (char*) buffer, st.st_size);
336 // close file
337 ::close(file_handle);
338 // construct ClassFileStream
339 if (num_read == (size_t)st.st_size) {
340 if (UsePerfData) {
341 ClassLoader::perf_sys_classfile_bytes_read()->inc(num_read);
342 }
343 #ifdef ASSERT
344 // Freeing path is a no-op here as buffer prevents it from being reclaimed. But we keep it for
345 // debug builds so that we guard against use-after-free bugs.
346 FREE_RESOURCE_ARRAY_IN_THREAD(current, path, path_len);
347 #endif
348 // We don't verify the length of the classfile stream fits in an int, but this is the
349 // bootloader so we have control of this.
350 // Resource allocated
351 return new ClassFileStream(buffer,
352 checked_cast<int>(st.st_size),
353 _dir);
354 }
355 }
356 }
357 FREE_RESOURCE_ARRAY_IN_THREAD(current, path, path_len);
358 return nullptr;
359 }
360
361 ClassPathZipEntry::ClassPathZipEntry(jzfile* zip, const char* zip_name) : ClassPathEntry() {
362 _zip = zip;
363 _zip_name = copy_path(zip_name);
364 }
365
366 ClassPathZipEntry::~ClassPathZipEntry() {
367 ZipLibrary::close(_zip);
368 FREE_C_HEAP_ARRAY(_zip_name);
369 }
370
371 bool ClassPathZipEntry::has_entry(JavaThread* current, const char* name) {
372 ThreadToNativeFromVM ttn(current);
373 // check whether zip archive contains name
374 jint name_len;
375 jint filesize;
376 jzentry* entry = ZipLibrary::find_entry(_zip, name, &filesize, &name_len);
377 if (entry == nullptr) {
378 return false;
379 } else {
380 ZipLibrary::free_entry(_zip, entry);
381 return true;
382 }
383 }
384
385 u1* ClassPathZipEntry::open_entry(JavaThread* current, const char* name, jint* filesize, bool nul_terminate) {
386 // enable call to C land
387 ThreadToNativeFromVM ttn(current);
388 // check whether zip archive contains name
389 jint name_len;
390 jzentry* entry = ZipLibrary::find_entry(_zip, name, filesize, &name_len);
391 if (entry == nullptr) return nullptr;
392 u1* buffer;
393 char name_buf[128];
394 char* filename;
395 if (name_len < 128) {
396 filename = name_buf;
397 } else {
398 filename = NEW_RESOURCE_ARRAY(char, name_len + 1);
399 }
400
401 // read contents into resource array
402 size_t size = (uint32_t)(*filesize);
403 if (nul_terminate) {
404 if (sizeof(size) == sizeof(uint32_t) && size == UINT_MAX) {
405 return nullptr; // 32-bit integer overflow will occur.
406 }
407 size++;
408 }
409 buffer = NEW_RESOURCE_ARRAY(u1, size);
410 if (!ZipLibrary::read_entry(_zip, entry, buffer, filename)) {
411 return nullptr;
412 }
413
414 // return result
415 if (nul_terminate) {
416 buffer[size - 1] = 0;
417 }
418 return buffer;
419 }
420
421 ClassFileStream* ClassPathZipEntry::open_stream(JavaThread* current, const char* name) {
422 jint filesize;
423 u1* buffer = open_entry(current, name, &filesize, false);
424 if (buffer == nullptr) {
425 return nullptr;
426 }
427 if (UsePerfData) {
428 ClassLoader::perf_sys_classfile_bytes_read()->inc(filesize);
429 }
430 // Resource allocated
431 return new ClassFileStream(buffer,
432 filesize,
433 _zip_name);
434 }
435
436 DEBUG_ONLY(ClassPathImageEntry* ClassPathImageEntry::_singleton = nullptr;)
437
438 void ClassPathImageEntry::close_jimage() {
439 jimage_close();
440 }
441
442 ClassPathImageEntry::ClassPathImageEntry(const char* name) :
443 ClassPathEntry() {
444 guarantee(jimage_is_initialized(), "jimage is not initialized");
445 guarantee(name != nullptr, "jimage file name is null");
446
447 assert(_singleton == nullptr, "VM supports only one jimage");
448 DEBUG_ONLY(_singleton = this);
449 size_t len = strlen(name) + 1;
450 _name = copy_path(name);
451 }
452
453 ClassFileStream* ClassPathImageEntry::open_stream(JavaThread* current, const char* name) {
454 return open_stream_for_loader(current, name, ClassLoaderData::the_null_class_loader_data());
455 }
456
457 // For a class in a named module, look it up in the jimage file using this syntax:
458 // /<module-name>/<package-name>/<base-class>
459 //
460 // Assumptions:
461 // 1. There are no unnamed modules in the jimage file.
462 // 2. A package is in at most one module in the jimage file.
463 //
464 ClassFileStream* ClassPathImageEntry::open_stream_for_loader(JavaThread* current, const char* name, ClassLoaderData* loader_data) {
465 const bool is_preview = is_preview_enabled();
466
467 jlong size;
468 JImageLocationRef location = 0;
469
470 TempNewSymbol class_name = SymbolTable::new_symbol(name);
471 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
472
473 if (pkg_name != nullptr) {
474 if (!Universe::is_module_initialized()) {
475 location = jimage_find_resource(JAVA_BASE_NAME, name, is_preview, &size);
476 } else {
477 PackageEntry* package_entry = ClassLoader::get_package_entry(pkg_name, loader_data);
478 if (package_entry != nullptr) {
479 ResourceMark rm(current);
480 // Get the module name
481 ModuleEntry* module = package_entry->module();
482 assert(module != nullptr, "Boot classLoader package missing module");
483 assert(module->is_named(), "Boot classLoader package is in unnamed module");
484 const char* module_name = module->name()->as_C_string();
485 if (module_name != nullptr) {
486 location = jimage_find_resource(module_name, name, is_preview, &size);
487 }
488 }
489 }
490 }
491
492 if (location != 0) {
493 if (UsePerfData) {
494 ClassLoader::perf_sys_classfile_bytes_read()->inc(size);
495 }
496 char* data = NEW_RESOURCE_ARRAY(char, size);
497 (*JImageGetResource)(jimage_non_null(), location, data, size);
498 // Resource allocated
499 assert(this == ClassLoader::get_jrt_entry(), "must be");
500 return new ClassFileStream((u1*)data,
501 checked_cast<int>(size),
502 _name,
503 true); // from_boot_loader_modules_image
504 }
505
506 return nullptr;
507 }
508
509 bool ClassPathImageEntry::is_modules_image() const {
510 assert(this == _singleton, "VM supports a single jimage");
511 assert(this == ClassLoader::get_jrt_entry(), "must be used for jrt entry");
512 return true;
513 }
514
515 ModuleClassPathList::ModuleClassPathList(Symbol* module_name) {
516 _module_name = module_name;
517 _module_first_entry = nullptr;
518 _module_last_entry = nullptr;
519 }
520
521 ModuleClassPathList::~ModuleClassPathList() {
522 // Clean out each ClassPathEntry on list
523 ClassPathEntry* e = _module_first_entry;
524 while (e != nullptr) {
525 ClassPathEntry* next_entry = e->next();
526 delete e;
527 e = next_entry;
528 }
529 }
530
531 void ModuleClassPathList::add_to_list(ClassPathEntry* new_entry) {
532 if (new_entry != nullptr) {
533 if (_module_last_entry == nullptr) {
534 _module_first_entry = _module_last_entry = new_entry;
535 } else {
536 _module_last_entry->set_next(new_entry);
537 _module_last_entry = new_entry;
538 }
539 }
540 }
541
542 void ClassLoader::trace_class_path(const char* msg, const char* name) {
543 LogTarget(Info, class, path) lt;
544 if (lt.is_enabled()) {
545 LogStream ls(lt);
546 if (msg) {
547 ls.print("%s", msg);
548 }
549 if (name) {
550 if (strlen(name) < 256) {
551 ls.print("%s", name);
552 } else {
553 // For very long paths, we need to print each character separately,
554 // as print_cr() has a length limit
555 while (name[0] != '\0') {
556 ls.print("%c", name[0]);
557 name++;
558 }
559 }
560 }
561 ls.cr();
562 }
563 }
564
565 void ClassLoader::setup_bootstrap_search_path(JavaThread* current) {
566 const char* bootcp = Arguments::get_boot_class_path();
567 assert(bootcp != nullptr, "Boot class path must not be nullptr");
568 if (PrintSharedArchiveAndExit) {
569 // Don't print bootcp - this is the bootcp of this current VM process, not necessarily
570 // the same as the boot classpath of the shared archive.
571 } else {
572 trace_class_path("bootstrap loader class path=", bootcp);
573 }
574 setup_bootstrap_search_path_impl(current, bootcp);
575 }
576
577 void ClassLoader::close_jrt_image() {
578 // Not applicable for exploded builds
579 if (!ClassLoader::has_jrt_entry()) return;
580 _jrt_entry->close_jimage();
581 }
582
583 // Construct the array of module/path pairs as specified to --patch-module
584 // for the boot loader to search ahead of the jimage, if the class being
585 // loaded is defined to a module that has been specified to --patch-module.
586 void ClassLoader::setup_patch_mod_entries() {
587 JavaThread* current = JavaThread::current();
588 GrowableArray<ModulePatchPath*>* patch_mod_args = Arguments::get_patch_mod_prefix();
589 int num_of_entries = patch_mod_args->length();
590
591 // Set up the boot loader's _patch_mod_entries list
592 _patch_mod_entries = new (mtModule) GrowableArray<ModuleClassPathList*>(num_of_entries, mtModule);
593
594 for (int i = 0; i < num_of_entries; i++) {
595 const char* module_name = (patch_mod_args->at(i))->module_name();
596 Symbol* const module_sym = SymbolTable::new_symbol(module_name);
597 assert(module_sym != nullptr, "Failed to obtain Symbol for module name");
598 ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
599
600 char* class_path = (patch_mod_args->at(i))->path_string();
601 ResourceMark rm(current);
602 ClasspathStream cp_stream(class_path);
603
604 while (cp_stream.has_next()) {
605 const char* path = cp_stream.get_next();
606 struct stat st;
607 if (os::stat(path, &st) == 0) {
608 // File or directory found
609 ClassPathEntry* new_entry = create_class_path_entry(current, path, &st);
610 // If the path specification is valid, enter it into this module's list
611 if (new_entry != nullptr) {
612 module_cpl->add_to_list(new_entry);
613 }
614 }
615 }
616
617 // Record the module into the list of --patch-module entries only if
618 // valid ClassPathEntrys have been created
619 if (module_cpl->module_first_entry() != nullptr) {
620 _patch_mod_entries->push(module_cpl);
621 }
622 }
623 }
624
625 // Determine whether the module has been patched via the command-line
626 // option --patch-module
627 bool ClassLoader::is_in_patch_mod_entries(Symbol* module_name) {
628 if (_patch_mod_entries != nullptr && _patch_mod_entries->is_nonempty()) {
629 int table_len = _patch_mod_entries->length();
630 for (int i = 0; i < table_len; i++) {
631 ModuleClassPathList* patch_mod = _patch_mod_entries->at(i);
632 if (module_name->fast_compare(patch_mod->module_name()) == 0) {
633 return true;
634 }
635 }
636 }
637 return false;
638 }
639
640 // Set up the _jrt_entry if present and boot append path
641 void ClassLoader::setup_bootstrap_search_path_impl(JavaThread* current, const char *class_path) {
642 ResourceMark rm(current);
643 ClasspathStream cp_stream(class_path);
644 bool set_base_piece = true;
645
646 #if INCLUDE_CDS
647 if (CDSConfig::is_dumping_archive()) {
648 if (!Arguments::has_jimage()) {
649 vm_exit_during_initialization("CDS is not supported in exploded JDK build", nullptr);
650 }
651 }
652 #endif
653
654 while (cp_stream.has_next()) {
655 const char* path = cp_stream.get_next();
656
657 if (set_base_piece) {
658 // The first time through the bootstrap_search setup, it must be determined
659 // what the base or core piece of the boot loader search is. Either a java runtime
660 // image is present or this is an exploded module build situation.
661 assert(string_ends_with(path, MODULES_IMAGE_NAME) || string_ends_with(path, JAVA_BASE_NAME),
662 "Incorrect boot loader search path, no java runtime image or " JAVA_BASE_NAME " exploded build");
663 struct stat st;
664 if (os::stat(path, &st) == 0) {
665 // Directory found
666 if (jimage_is_open()) {
667 assert(Arguments::has_jimage(), "sanity check");
668 const char* canonical_path = get_canonical_path(path, current);
669 assert(canonical_path != nullptr, "canonical_path issue");
670
671 // Hand over lifecycle control of the JImage file to the _jrt_entry singleton
672 // (see ClassPathImageEntry::close_jimage). The image must be initialized by now.
673 _jrt_entry = new ClassPathImageEntry(canonical_path);
674 assert(_jrt_entry != nullptr && _jrt_entry->is_modules_image(), "No java runtime image present");
675 } // else it's an exploded build.
676 } else {
677 // If path does not exist, exit
678 vm_exit_during_initialization("Unable to establish the boot loader search path", path);
679 }
680 set_base_piece = false;
681 } else {
682 // Every entry on the boot class path after the initial base piece,
683 // which is set by os::set_boot_path(), is considered an appended entry.
684 update_class_path_entry_list(current, path);
685 }
686 }
687 }
688
689 // Gets the exploded path for the named module. The memory for the path
690 // is allocated on the C heap if `c_heap` is true otherwise in the resource area.
691 static const char* get_exploded_module_path(const char* module_name, bool c_heap) {
692 const char *home = Arguments::get_java_home();
693 const char file_sep = os::file_separator()[0];
694 // 10 represents the length of "modules" (7) + 2 file separators + \0
695 size_t len = strlen(home) + strlen(module_name) + 10;
696 char *path = c_heap ? NEW_C_HEAP_ARRAY(char, len, mtModule) : NEW_RESOURCE_ARRAY(char, len);
697 jio_snprintf(path, len, "%s%cmodules%c%s", home, file_sep, file_sep, module_name);
698 return path;
699 }
700
701 // Gets a preview path for a given class path as a resource.
702 static const char* get_preview_path(const char* path) {
703 const char file_sep = os::file_separator()[0];
704 // 18 represents the length of "META-INF" (8) + "preview" (7) + 2 file separators + \0
705 size_t len = strlen(path) + 18;
706 char *preview_path = NEW_RESOURCE_ARRAY(char, len);
707 jio_snprintf(preview_path, len, "%s%cMETA-INF%cpreview", path, file_sep, file_sep);
708 return preview_path;
709 }
710
711 // During an exploded modules build, each module defined to the boot loader
712 // will be added to the ClassLoader::_exploded_entries array.
713 void ClassLoader::add_to_exploded_build_list(JavaThread* current, Symbol* module_sym) {
714 assert(!ClassLoader::has_jrt_entry(), "Exploded build not applicable");
715 assert(_exploded_entries != nullptr, "_exploded_entries was not initialized");
716
717 // Find the module's symbol
718 ResourceMark rm(current);
719 const char *module_name = module_sym->as_C_string();
720 const char *path = get_exploded_module_path(module_name, false);
721
722 struct stat st;
723 if (os::stat(path, &st) == 0) {
724 // Directory found
725 ClassPathEntry* new_entry = create_class_path_entry(current, path, &st);
726 // If the path specification is valid, enter it into this module's list.
727 // There is no need to check for duplicate modules in the exploded entry list,
728 // since no two modules with the same name can be defined to the boot loader.
729 // This is checked at module definition time in Modules::define_module.
730 if (new_entry != nullptr) {
731 ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
732 log_info(class, load)("path: %s", path);
733
734 // If we are in preview mode, attempt to add a preview entry *before* the
735 // new class path entry if a preview path exists.
736 if (is_preview_enabled()) {
737 const char* preview_path = get_preview_path(path);
738 if (os::stat(preview_path, &st) == 0) {
739 ClassPathEntry* preview_entry = create_class_path_entry(current, preview_path, &st);
740 if (preview_entry != nullptr) {
741 module_cpl->add_to_list(preview_entry);
742 log_info(class, load)("preview path: %s", preview_path);
743 }
744 }
745 }
746
747 module_cpl->add_to_list(new_entry);
748 {
749 MutexLocker ml(current, Module_lock);
750 _exploded_entries->push(module_cpl);
751 }
752 }
753 }
754 }
755
756 jzfile* ClassLoader::open_zip_file(const char* canonical_path, char** error_msg, JavaThread* thread) {
757 // enable call to C land
758 ThreadToNativeFromVM ttn(thread);
759 HandleMark hm(thread);
760 return ZipLibrary::open(canonical_path, error_msg);
761 }
762
763 ClassPathEntry* ClassLoader::create_class_path_entry(JavaThread* current,
764 const char *path, const struct stat* st) {
765 ClassPathEntry* new_entry = nullptr;
766 if ((st->st_mode & S_IFMT) == S_IFREG) {
767 ResourceMark rm(current);
768 // Regular file, should be a zip file
769 // Canonicalized filename
770 const char* canonical_path = get_canonical_path(path, current);
771 if (canonical_path == nullptr) {
772 return nullptr;
773 }
774 char* error_msg = nullptr;
775 jzfile* zip = open_zip_file(canonical_path, &error_msg, current);
776 if (zip != nullptr && error_msg == nullptr) {
777 new_entry = new ClassPathZipEntry(zip, path);
778 } else {
779 log_info(class, path)("failed: %s, err: %s", path, error_msg);
780 return nullptr;
781 }
782 log_info(class, path)("opened: %s", path);
783 log_info(class, load)("opened: %s", path);
784 } else {
785 // Directory
786 new_entry = new ClassPathDirEntry(path);
787 log_info(class, load)("path: %s", path);
788 }
789 return new_entry;
790 }
791
792
793 // Create a class path zip entry for a given path (return null if not found
794 // or zip/JAR file cannot be opened)
795 ClassPathZipEntry* ClassLoader::create_class_path_zip_entry(const char *path) {
796 // check for a regular file
797 struct stat st;
798 if (os::stat(path, &st) == 0) {
799 if ((st.st_mode & S_IFMT) == S_IFREG) {
800 JavaThread* thread = JavaThread::current();
801 ResourceMark rm(thread);
802 const char* canonical_path = get_canonical_path(path, thread);
803 if (canonical_path != nullptr) {
804 char* error_msg = nullptr;
805 jzfile* zip = open_zip_file(canonical_path, &error_msg, thread);
806 if (zip != nullptr && error_msg == nullptr) {
807 // create using canonical path
808 return new ClassPathZipEntry(zip, canonical_path);
809 }
810 }
811 }
812 }
813 return nullptr;
814 }
815
816 // The boot append entries are added with a lock, and read lock free.
817 void ClassLoader::add_to_boot_append_entries(ClassPathEntry *new_entry) {
818 if (new_entry != nullptr) {
819 MutexLocker ml(Bootclasspath_lock, Mutex::_no_safepoint_check_flag);
820 if (_last_append_entry == nullptr) {
821 _last_append_entry = new_entry;
822 assert(first_append_entry() == nullptr, "boot loader's append class path entry list not empty");
823 AtomicAccess::release_store(&_first_append_entry_list, new_entry);
824 } else {
825 _last_append_entry->set_next(new_entry);
826 _last_append_entry = new_entry;
827 }
828 }
829 }
830
831 // Returns true IFF the file/dir exists and the entry was successfully created.
832 bool ClassLoader::update_class_path_entry_list(JavaThread* current, const char *path) {
833 struct stat st;
834 if (os::stat(path, &st) == 0) {
835 // File or directory found
836 ClassPathEntry* new_entry = nullptr;
837 new_entry = create_class_path_entry(current, path, &st);
838 if (new_entry == nullptr) {
839 return false;
840 }
841
842 // Do not reorder the bootclasspath which would break get_system_package().
843 // Add new entry to linked list
844 add_to_boot_append_entries(new_entry);
845 return true;
846 } else {
847 return false;
848 }
849 }
850
851 static void print_module_entry_table(const GrowableArray<ModuleClassPathList*>* const module_list) {
852 ResourceMark rm;
853 int num_of_entries = module_list->length();
854 for (int i = 0; i < num_of_entries; i++) {
855 ClassPathEntry* e;
856 ModuleClassPathList* mpl = module_list->at(i);
857 tty->print("%s=", mpl->module_name()->as_C_string());
858 e = mpl->module_first_entry();
859 while (e != nullptr) {
860 tty->print("%s", e->name());
861 e = e->next();
862 if (e != nullptr) {
863 tty->print("%s", os::path_separator());
864 }
865 }
866 tty->print(" ;");
867 }
868 }
869
870 void ClassLoader::print_bootclasspath() {
871 ClassPathEntry* e;
872 tty->print("[bootclasspath= ");
873
874 // Print --patch-module module/path specifications first
875 if (_patch_mod_entries != nullptr) {
876 print_module_entry_table(_patch_mod_entries);
877 }
878
879 // [jimage | exploded modules build]
880 if (has_jrt_entry()) {
881 // Print the location of the java runtime image
882 tty->print("%s ;", _jrt_entry->name());
883 } else {
884 // Print exploded module build path specifications
885 if (_exploded_entries != nullptr) {
886 print_module_entry_table(_exploded_entries);
887 }
888 }
889
890 // appended entries
891 e = first_append_entry();
892 while (e != nullptr) {
893 tty->print("%s ;", e->name());
894 e = e->next();
895 }
896 tty->print_cr("]");
897 }
898
899 void* ClassLoader::dll_lookup(void* lib, const char* name, const char* path) {
900 void* func = os::dll_lookup(lib, name);
901 if (func == nullptr) {
902 char msg[256] = "";
903 jio_snprintf(msg, sizeof(msg), "Could not resolve \"%s\"", name);
904 vm_exit_during_initialization(msg, path);
905 }
906 return func;
907 }
908
909 void ClassLoader::load_java_library() {
910 assert(CanonicalizeEntry == nullptr, "should not load java library twice");
911 if (is_vm_statically_linked()) {
912 CanonicalizeEntry = CAST_TO_FN_PTR(canonicalize_fn_t, os::lookup_function("JDK_Canonicalize"));
913 assert(CanonicalizeEntry != nullptr, "could not lookup JDK_Canonicalize");
914 return;
915 }
916
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 assert(CanonicalizeEntry != nullptr, "could not lookup JDK_Canonicalize in java library");
924 }
925
926 void ClassLoader::load_jimage_library() {
927 assert(JImageOpen == nullptr, "should not load jimage library twice");
928
929 if (is_vm_statically_linked()) {
930 JImageOpen = CAST_TO_FN_PTR(JImageOpen_t, os::lookup_function("JIMAGE_Open"));
931 JImageClose = CAST_TO_FN_PTR(JImageClose_t, os::lookup_function("JIMAGE_Close"));
932 JImageFindResource = CAST_TO_FN_PTR(JImageFindResource_t, os::lookup_function("JIMAGE_FindResource"));
933 JImageGetResource = CAST_TO_FN_PTR(JImageGetResource_t, os::lookup_function("JIMAGE_GetResource"));
934 assert(JImageOpen != nullptr && JImageClose != nullptr &&
935 JImageFindResource != nullptr && JImageGetResource != nullptr,
936 "could not lookup all jimage library functions");
937 return;
938 }
939
940 char path[JVM_MAXPATHLEN];
941 char ebuf[1024];
942 void* handle = nullptr;
943 if (os::dll_locate_lib(path, sizeof(path), Arguments::get_dll_dir(), "jimage")) {
944 handle = os::dll_load(path, ebuf, sizeof ebuf);
945 }
946 if (handle == nullptr) {
947 vm_exit_during_initialization("Unable to load jimage library", path);
948 }
949
950 JImageOpen = CAST_TO_FN_PTR(JImageOpen_t, dll_lookup(handle, "JIMAGE_Open", path));
951 JImageClose = CAST_TO_FN_PTR(JImageClose_t, dll_lookup(handle, "JIMAGE_Close", path));
952 JImageFindResource = CAST_TO_FN_PTR(JImageFindResource_t, dll_lookup(handle, "JIMAGE_FindResource", path));
953 JImageGetResource = CAST_TO_FN_PTR(JImageGetResource_t, dll_lookup(handle, "JIMAGE_GetResource", path));
954 assert(JImageOpen != nullptr && JImageClose != nullptr &&
955 JImageFindResource != nullptr && JImageGetResource != nullptr,
956 "could not lookup all jimage library functions in jimage library");
957 }
958
959 int ClassLoader::crc32(int crc, const char* buf, int len) {
960 return ZipLibrary::crc32(crc, (const jbyte*)buf, len);
961 }
962
963 oop ClassLoader::get_system_package(const char* name, TRAPS) {
964 // Look up the name in the boot loader's package entry table.
965 if (name != nullptr) {
966 TempNewSymbol package_sym = SymbolTable::new_symbol(name);
967 // Look for the package entry in the boot loader's package entry table.
968 PackageEntry* package =
969 ClassLoaderData::the_null_class_loader_data()->packages()->lookup_only(package_sym);
970
971 // Return null if package does not exist or if no classes in that package
972 // have been loaded.
973 if (package != nullptr && package->has_loaded_class()) {
974 ModuleEntry* module = package->module();
975 if (module->location() != nullptr) {
976 ResourceMark rm(THREAD);
977 Handle ml = java_lang_String::create_from_str(
978 module->location()->as_C_string(), THREAD);
979 return ml();
980 }
981 // Return entry on boot loader class path.
982 Handle cph = java_lang_String::create_from_str(
983 ClassLoader::classpath_entry(package->classpath_index())->name(), THREAD);
984 return cph();
985 }
986 }
987 return nullptr;
988 }
989
990 refArrayOop ClassLoader::get_system_packages(TRAPS) {
991 ResourceMark rm(THREAD);
992 // List of pointers to PackageEntrys that have loaded classes.
993 PackageEntryTable* pe_table =
994 ClassLoaderData::the_null_class_loader_data()->packages();
995 GrowableArray<PackageEntry*>* loaded_class_pkgs = pe_table->get_system_packages();
996
997 // Allocate objArray and fill with java.lang.String
998 refArrayOop r = oopFactory::new_refArray(vmClasses::String_klass(),
999 loaded_class_pkgs->length(),
1000 CHECK_NULL);
1001 refArrayHandle result(THREAD, r);
1002 for (int x = 0; x < loaded_class_pkgs->length(); x++) {
1003 PackageEntry* package_entry = loaded_class_pkgs->at(x);
1004 Handle str = java_lang_String::create_from_symbol(package_entry->name(), CHECK_NULL);
1005 result->obj_at_put(x, str());
1006 }
1007 return result();
1008 }
1009
1010 // caller needs ResourceMark
1011 const char* ClassLoader::file_name_for_class_name(const char* class_name,
1012 int class_name_len) {
1013 assert(class_name != nullptr, "invariant");
1014 assert((int)strlen(class_name) == class_name_len, "invariant");
1015
1016 static const char class_suffix[] = ".class";
1017 size_t class_suffix_len = sizeof(class_suffix);
1018
1019 char* const file_name = NEW_RESOURCE_ARRAY(char,
1020 class_name_len +
1021 class_suffix_len); // includes term null
1022
1023 strncpy(file_name, class_name, class_name_len);
1024 strncpy(&file_name[class_name_len], class_suffix, class_suffix_len);
1025
1026 return file_name;
1027 }
1028
1029 static ClassPathEntry* find_first_module_cpe(ModuleEntry* mod_entry,
1030 const GrowableArray<ModuleClassPathList*>* const module_list) {
1031 int num_of_entries = module_list->length();
1032 const Symbol* class_module_name = mod_entry->name();
1033
1034 // Loop through all the modules in either the patch-module or exploded entries looking for module
1035 for (int i = 0; i < num_of_entries; i++) {
1036 ModuleClassPathList* module_cpl = module_list->at(i);
1037 Symbol* module_cpl_name = module_cpl->module_name();
1038
1039 if (module_cpl_name->fast_compare(class_module_name) == 0) {
1040 // Class' module has been located.
1041 return module_cpl->module_first_entry();
1042 }
1043 }
1044 return nullptr;
1045 }
1046
1047
1048 // Search the module list for the class file stream based on the file name and java package
1049 ClassFileStream* ClassLoader::search_module_entries(JavaThread* current,
1050 const GrowableArray<ModuleClassPathList*>* const module_list,
1051 PackageEntry* pkg_entry, // Java package entry derived from the class name
1052 const char* const file_name) {
1053 ClassFileStream* stream = nullptr;
1054
1055 // Find the defining module in the boot loader's module entry table
1056 ModuleEntry* mod_entry = (pkg_entry != nullptr) ? pkg_entry->module() : nullptr;
1057
1058 // If the module system has not defined java.base yet, then
1059 // classes loaded are assumed to be defined to java.base.
1060 // When java.base is eventually defined by the module system,
1061 // all packages of classes that have been previously loaded
1062 // are verified in ModuleEntryTable::verify_javabase_packages().
1063 if (!Universe::is_module_initialized() &&
1064 !ModuleEntryTable::javabase_defined() &&
1065 mod_entry == nullptr) {
1066 mod_entry = ModuleEntryTable::javabase_moduleEntry();
1067 }
1068
1069 // The module must be a named module
1070 ClassPathEntry* e = nullptr;
1071 if (mod_entry != nullptr && mod_entry->is_named()) {
1072 if (module_list == _exploded_entries) {
1073 // The exploded build entries can be added to at any time so a lock is
1074 // needed when searching them.
1075 assert(!ClassLoader::has_jrt_entry(), "Must be exploded build");
1076 MutexLocker ml(current, Module_lock);
1077 e = find_first_module_cpe(mod_entry, module_list);
1078 } else {
1079 e = find_first_module_cpe(mod_entry, module_list);
1080 }
1081 }
1082
1083 // Try to load the class from the module's ClassPathEntry list.
1084 while (e != nullptr) {
1085 stream = e->open_stream(current, file_name);
1086 // No context.check is required since CDS is not supported
1087 // for an exploded modules build or if --patch-module is specified.
1088 if (nullptr != stream) {
1089 return stream;
1090 }
1091 e = e->next();
1092 }
1093 // If the module was located, break out even if the class was not
1094 // located successfully from that module's ClassPathEntry list.
1095 // There will not be another valid entry for that module.
1096 return nullptr;
1097 }
1098
1099 // Called by the boot classloader to load classes
1100 InstanceKlass* ClassLoader::load_class(Symbol* name, PackageEntry* pkg_entry, bool search_append_only, TRAPS) {
1101 assert(name != nullptr, "invariant");
1102
1103 ResourceMark rm(THREAD);
1104 HandleMark hm(THREAD);
1105
1106 const char* const class_name = name->as_C_string();
1107
1108 EventMarkClassLoading m("Loading class %s", class_name);
1109
1110 const char* const file_name = file_name_for_class_name(class_name,
1111 name->utf8_length());
1112 assert(file_name != nullptr, "invariant");
1113
1114 // Lookup stream for parsing .class file
1115 ClassFileStream* stream = nullptr;
1116 s2 classpath_index = 0;
1117 ClassPathEntry* e = nullptr;
1118 bool is_patched = false;
1119
1120 // If search_append_only is true, boot loader visibility boundaries are
1121 // set to be _first_append_entry to the end. This includes:
1122 // [-Xbootclasspath/a]; [jvmti appended entries]
1123 //
1124 // If search_append_only is false, boot loader visibility boundaries are
1125 // set to be the --patch-module entries plus the base piece. This includes:
1126 // [--patch-module=<module>=<file>(<pathsep><file>)*]; [jimage | exploded module build]
1127 //
1128
1129 // Load Attempt #1: --patch-module
1130 // Determine the class' defining module. If it appears in the _patch_mod_entries,
1131 // attempt to load the class from those locations specific to the module.
1132 // Specifications to --patch-module can contain a partial number of classes
1133 // that are part of the overall module definition. So if a particular class is not
1134 // found within its module specification, the search should continue to Load Attempt #2.
1135 // Note: The --patch-module entries are never searched if the boot loader's
1136 // visibility boundary is limited to only searching the append entries.
1137 if (_patch_mod_entries != nullptr && !search_append_only) {
1138 // At CDS dump time, the --patch-module entries are ignored. That means a
1139 // class is still loaded from the runtime image even if it might
1140 // appear in the _patch_mod_entries. The runtime shared class visibility
1141 // check will determine if a shared class is visible based on the runtime
1142 // environment, including the runtime --patch-module setting.
1143 if (!Arguments::is_valhalla_enabled()) {
1144 // Dynamic dumping requires UseSharedSpaces to be enabled. Since --patch-module
1145 // is not supported with UseSharedSpaces, we can never come here during dynamic dumping.
1146 assert(!CDSConfig::is_dumping_archive(), "CDS doesn't support --patch-module during dumping");
1147 }
1148 if (Arguments::is_valhalla_enabled() || !CDSConfig::is_dumping_static_archive()) {
1149 stream = search_module_entries(THREAD, _patch_mod_entries, pkg_entry, file_name);
1150 if (stream != nullptr) {
1151 is_patched = true;
1152 }
1153 }
1154 }
1155
1156 // Load Attempt #2: [jimage | exploded build]
1157 if (!search_append_only && (nullptr == stream)) {
1158 if (has_jrt_entry()) {
1159 e = _jrt_entry;
1160 stream = _jrt_entry->open_stream(THREAD, file_name);
1161 } else {
1162 // Exploded build - attempt to locate class in its defining module's location.
1163 assert(_exploded_entries != nullptr, "No exploded build entries present");
1164 assert(!CDSConfig::is_dumping_archive(), "CDS dumping doesn't support exploded build");
1165 stream = search_module_entries(THREAD, _exploded_entries, pkg_entry, file_name);
1166 }
1167 }
1168
1169 // Load Attempt #3: [-Xbootclasspath/a]; [jvmti appended entries]
1170 if (search_append_only && (nullptr == stream)) {
1171 // For the boot loader append path search, the starting classpath_index
1172 // for the appended piece is always 1 to account for either the
1173 // _jrt_entry or the _exploded_entries.
1174 assert(classpath_index == 0, "The classpath_index has been incremented incorrectly");
1175 classpath_index = 1;
1176
1177 e = first_append_entry();
1178 while (e != nullptr) {
1179 stream = e->open_stream(THREAD, file_name);
1180 if (nullptr != stream) {
1181 break;
1182 }
1183 e = e->next();
1184 ++classpath_index;
1185 }
1186 }
1187
1188 if (nullptr == stream) {
1189 return nullptr;
1190 }
1191
1192 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
1193 Handle protection_domain;
1194 ClassLoadInfo cl_info(protection_domain);
1195
1196 InstanceKlass* result = KlassFactory::create_from_stream(stream,
1197 name,
1198 loader_data,
1199 cl_info,
1200 CHECK_NULL);
1201 result->set_classpath_index(classpath_index);
1202 if (is_patched) {
1203 result->set_shared_classpath_index(0);
1204 }
1205 return result;
1206 }
1207
1208 #if INCLUDE_CDS
1209 static const char* skip_uri_protocol(const char* source) {
1210 if (strncmp(source, "file:", 5) == 0) {
1211 // file: protocol path could start with file:/ or file:///
1212 // locate the char after all the forward slashes
1213 int offset = 5;
1214 while (*(source + offset) == '/') {
1215 offset++;
1216 }
1217 source += offset;
1218 // for non-windows platforms, move back one char as the path begins with a '/'
1219 #ifndef _WINDOWS
1220 source -= 1;
1221 #endif
1222 } else if (strncmp(source, "jrt:/", 5) == 0) {
1223 source += 5;
1224 }
1225 return source;
1226 }
1227
1228 static char decode_percent_encoded(const char *str, size_t& index) {
1229 if (str[index] == '%'
1230 && isxdigit(str[index + 1])
1231 && isxdigit(str[index + 2])) {
1232 char hex[3];
1233 hex[0] = str[index + 1];
1234 hex[1] = str[index + 2];
1235 hex[2] = '\0';
1236 index += 2;
1237 return (char) strtol(hex, nullptr, 16);
1238 }
1239 return str[index];
1240 }
1241
1242 char* ClassLoader::uri_to_path(const char* uri) {
1243 const size_t len = strlen(uri) + 1;
1244 char* path = NEW_RESOURCE_ARRAY(char, len);
1245
1246 uri = skip_uri_protocol(uri);
1247
1248 if (strncmp(uri, "//", 2) == 0) {
1249 // Skip the empty "authority" part
1250 uri += 2;
1251 }
1252
1253 #ifdef _WINDOWS
1254 if (uri[0] == '/') {
1255 // Absolute path name on Windows does not begin with a slash
1256 uri += 1;
1257 }
1258 #endif
1259
1260 size_t path_index = 0;
1261 for (size_t i = 0; i < strlen(uri); ++i) {
1262 char decoded = decode_percent_encoded(uri, i);
1263 path[path_index++] = decoded;
1264 }
1265 path[path_index] = '\0';
1266 return path;
1267 }
1268
1269 // Record the shared classpath index and loader type for classes loaded
1270 // by the builtin loaders at dump time.
1271 void ClassLoader::record_result(JavaThread* current, InstanceKlass* ik,
1272 const ClassFileStream* stream, bool redefined) {
1273 assert(CDSConfig::is_dumping_archive(), "sanity");
1274 assert(stream != nullptr, "sanity");
1275
1276 if (ik->is_hidden()) {
1277 record_hidden_class(ik);
1278 return;
1279 }
1280
1281 if (ik->shared_classpath_index() == 0 && ik->defined_by_boot_loader()) {
1282 return;
1283 }
1284
1285 oop loader = ik->class_loader();
1286 char* src = (char*)stream->source();
1287 if (src == nullptr) {
1288 ik->set_shared_classpath_index(-1); // unsupported location
1289 return;
1290 }
1291
1292 if (!SystemDictionaryShared::is_builtin_loader(ik->class_loader_data())) {
1293 // A class loaded by a user-defined classloader.
1294 assert(ik->shared_classpath_index() < 0, "not assigned yet");
1295 ik->set_shared_classpath_index(UNREGISTERED_INDEX);
1296 SystemDictionaryShared::set_shared_class_misc_info(ik, (ClassFileStream*)stream);
1297 return;
1298 }
1299
1300 assert(has_jrt_entry(), "CDS dumping does not support exploded JDK build");
1301
1302 ResourceMark rm(current);
1303 int classpath_index = -1;
1304 bool found_invalid = false;
1305
1306 PackageEntry* pkg_entry = ik->package();
1307
1308 if (!AOTClassLocationConfig::dumptime_is_ready()) {
1309 // The shared path table is set up after module system initialization.
1310 // The path table contains no entry before that. Any classes loaded prior
1311 // to the setup of the shared path table must be from the modules image.
1312 assert(stream->from_boot_loader_modules_image(), "stream must be loaded by boot loader from modules image");
1313 classpath_index = 0;
1314 } else {
1315 // Save the path from the file: protocol or the module name from the jrt: protocol
1316 // if no protocol prefix is found, path is the same as stream->source(). This path
1317 // must be valid since the class has been successfully parsed.
1318 const char* path = ClassLoader::uri_to_path(src);
1319 assert(path != nullptr, "sanity");
1320 AOTClassLocationConfig::dumptime_iterate([&] (AOTClassLocation* cl) {
1321 int i = cl->index();
1322 // for index 0 and the stream->source() is the modules image or has the jrt: protocol.
1323 // The class must be from the runtime modules image.
1324 if (cl->is_modules_image() && (stream->from_boot_loader_modules_image() || string_starts_with(src, "jrt:"))) {
1325 classpath_index = i;
1326 } else if (os::same_files(cl->path(), path)) {
1327 // If the path (from the class stream source) is the same as the shared
1328 // class or module path, then we have a match.
1329 // src may come from the App/Platform class loaders, which would canonicalize
1330 // the file name. We cannot use strcmp to check for equality against cs->path().
1331 // We must use os::same_files (which is faster than canonicalizing cs->path()).
1332
1333 // null pkg_entry and pkg_entry in an unnamed module implies the class
1334 // is from the -cp or boot loader append path which consists of -Xbootclasspath/a
1335 // and jvmti appended entries.
1336 if ((pkg_entry == nullptr) || (pkg_entry->in_unnamed_module())) {
1337 // Ensure the index is within the -cp range before assigning
1338 // to the classpath_index.
1339 if (SystemDictionary::is_system_class_loader(loader) && cl->from_app_classpath()) {
1340 classpath_index = i;
1341 } else {
1342 if (cl->from_boot_classpath()) {
1343 if (loader != nullptr) {
1344 // Probably loaded by jdk/internal/loader/ClassLoaders$BootClassLoader. Don't archive
1345 // such classes.
1346 found_invalid = true;
1347 } else {
1348 classpath_index = i;
1349 }
1350 }
1351 }
1352 } else {
1353 // A class from a named module from the --module-path. Ensure the index is
1354 // within the --module-path range before assigning to the classpath_index.
1355 if ((pkg_entry != nullptr) && !(pkg_entry->in_unnamed_module()) && cl->from_module_path()) {
1356 classpath_index = i;
1357 }
1358 }
1359 }
1360 if (classpath_index >= 0 || found_invalid) {
1361 return false; // Break the AOTClassLocationConfig::dumptime_iterate() loop.
1362 } else {
1363 return true; // Keep iterating
1364 }
1365 });
1366 }
1367
1368 if (found_invalid) {
1369 assert(classpath_index == -1, "sanity");
1370 }
1371
1372 const char* const class_name = ik->name()->as_C_string();
1373 const char* const file_name = file_name_for_class_name(class_name,
1374 ik->name()->utf8_length());
1375 assert(file_name != nullptr, "invariant");
1376 record_result_for_builtin_loader(checked_cast<s2>(classpath_index), ik, redefined);
1377 }
1378
1379 void ClassLoader::record_result_for_builtin_loader(s2 classpath_index, InstanceKlass* result, bool redefined) {
1380 assert(CDSConfig::is_dumping_archive(), "sanity");
1381
1382 oop loader = result->class_loader();
1383 if (SystemDictionary::is_system_class_loader(loader)) {
1384 AOTClassLocationConfig::dumptime_set_has_app_classes();
1385 } else if (SystemDictionary::is_platform_class_loader(loader)) {
1386 AOTClassLocationConfig::dumptime_set_has_platform_classes();
1387 } else {
1388 precond(loader == nullptr);
1389 }
1390
1391 if (CDSConfig::is_dumping_preimage_static_archive() || CDSConfig::is_dumping_dynamic_archive()) {
1392 if (!AOTClassLocationConfig::dumptime()->is_valid_classpath_index(classpath_index, result)) {
1393 classpath_index = -1;
1394 }
1395 }
1396
1397 AOTClassLocationConfig::dumptime_update_max_used_index(classpath_index);
1398 result->set_shared_classpath_index(classpath_index);
1399 }
1400
1401 void ClassLoader::record_hidden_class(InstanceKlass* ik) {
1402 assert(ik->is_hidden(), "must be");
1403
1404 if (ik->defined_by_other_loaders()) {
1405 // We don't archive hidden classes for non-builtin loaders.
1406 return;
1407 }
1408
1409 if (HeapShared::is_lambda_proxy_klass(ik)) {
1410 InstanceKlass* nest_host = ik->nest_host_not_null();
1411 ik->set_shared_classpath_index(nest_host->shared_classpath_index());
1412 } else if (HeapShared::is_lambda_form_klass(ik)) {
1413 ik->set_shared_classpath_index(0);
1414 } else {
1415 // Generated invoker classes.
1416 if (ik->defined_by_app_loader()) {
1417 ik->set_shared_classpath_index(AOTClassLocationConfig::dumptime()->app_cp_start_index());
1418 } else {
1419 ik->set_shared_classpath_index(0);
1420 }
1421 }
1422 }
1423
1424 void ClassLoader::append_boot_classpath(ClassPathEntry* new_entry) {
1425 if (CDSConfig::is_using_archive()) {
1426 warning("Sharing is only supported for boot loader classes because bootstrap classpath has been appended");
1427 FileMapInfo::current_info()->set_has_platform_or_app_classes(false);
1428 if (DynamicArchive::is_mapped()) {
1429 FileMapInfo::dynamic_info()->set_has_platform_or_app_classes(false);
1430 }
1431 }
1432 add_to_boot_append_entries(new_entry);
1433 }
1434 #endif // INCLUDE_CDS
1435
1436 // Initialize the class loader's access to methods in libzip. Parse and
1437 // process the boot classpath into a list ClassPathEntry objects. Once
1438 // this list has been created, it must not change order (see class PackageInfo)
1439 // it can be appended to and is by jvmti.
1440
1441 void ClassLoader::initialize(TRAPS) {
1442 if (UsePerfData) {
1443 // jvmstat performance counters
1444 NEWPERFTICKCOUNTER(_perf_accumulated_time, SUN_CLS, "time");
1445 NEWPERFTICKCOUNTER(_perf_class_init_time, SUN_CLS, "classInitTime");
1446 NEWPERFTICKCOUNTER(_perf_class_init_selftime, SUN_CLS, "classInitTime.self");
1447 NEWPERFTICKCOUNTER(_perf_class_verify_time, SUN_CLS, "classVerifyTime");
1448 NEWPERFTICKCOUNTER(_perf_class_verify_selftime, SUN_CLS, "classVerifyTime.self");
1449 NEWPERFTICKCOUNTER(_perf_class_link_time, SUN_CLS, "classLinkedTime");
1450 NEWPERFTICKCOUNTER(_perf_class_link_selftime, SUN_CLS, "classLinkedTime.self");
1451 NEWPERFEVENTCOUNTER(_perf_classes_inited, SUN_CLS, "initializedClasses");
1452 NEWPERFEVENTCOUNTER(_perf_classes_linked, SUN_CLS, "linkedClasses");
1453 NEWPERFEVENTCOUNTER(_perf_classes_verified, SUN_CLS, "verifiedClasses");
1454
1455 NEWPERFTICKCOUNTER(_perf_shared_classload_time, SUN_CLS, "sharedClassLoadTime");
1456 NEWPERFTICKCOUNTER(_perf_sys_classload_time, SUN_CLS, "sysClassLoadTime");
1457 NEWPERFTICKCOUNTER(_perf_app_classload_time, SUN_CLS, "appClassLoadTime");
1458 NEWPERFTICKCOUNTER(_perf_app_classload_selftime, SUN_CLS, "appClassLoadTime.self");
1459 NEWPERFEVENTCOUNTER(_perf_app_classload_count, SUN_CLS, "appClassLoadCount");
1460 NEWPERFTICKCOUNTER(_perf_define_appclasses, SUN_CLS, "defineAppClasses");
1461 NEWPERFTICKCOUNTER(_perf_define_appclass_time, SUN_CLS, "defineAppClassTime");
1462 NEWPERFTICKCOUNTER(_perf_define_appclass_selftime, SUN_CLS, "defineAppClassTime.self");
1463 NEWPERFBYTECOUNTER(_perf_app_classfile_bytes_read, SUN_CLS, "appClassBytes");
1464 NEWPERFBYTECOUNTER(_perf_sys_classfile_bytes_read, SUN_CLS, "sysClassBytes");
1465 NEWPERFEVENTCOUNTER(_unsafe_defineClassCallCounter, SUN_CLS, "unsafeDefineClassCalls");
1466 NEWPERFTICKCOUNTER(_perf_secondary_hash_time, SUN_CLS, "secondarySuperHashTime");
1467 NEWPERFTICKCOUNTER(_perf_change_wx_time, SUN_CLS, "changeWXTime");
1468
1469 if (log_is_enabled(Info, perf, class, link)) {
1470 NEWPERFTICKCOUNTER(_perf_ik_link_methods_time, SUN_CLS, "linkMethodsTime");
1471 NEWPERFTICKCOUNTER(_perf_method_adapters_time, SUN_CLS, "makeAdaptersTime");
1472 NEWPERFEVENTCOUNTER(_perf_ik_link_methods_count, SUN_CLS, "linkMethodsCount");
1473 NEWPERFEVENTCOUNTER(_perf_method_adapters_count, SUN_CLS, "makeAdaptersCount");
1474
1475 NEWPERFTICKCOUNTER(_perf_resolve_indy_time, SUN_CLS, "resolve_invokedynamic_time");
1476 NEWPERFTICKCOUNTER(_perf_resolve_invokehandle_time, SUN_CLS, "resolve_invokehandle_time");
1477 NEWPERFTICKCOUNTER(_perf_resolve_mh_time, SUN_CLS, "resolve_MethodHandle_time");
1478 NEWPERFTICKCOUNTER(_perf_resolve_mt_time, SUN_CLS, "resolve_MethodType_time");
1479
1480 NEWPERFEVENTCOUNTER(_perf_resolve_indy_count, SUN_CLS, "resolve_invokedynamic_count");
1481 NEWPERFEVENTCOUNTER(_perf_resolve_invokehandle_count, SUN_CLS, "resolve_invokehandle_count");
1482 NEWPERFEVENTCOUNTER(_perf_resolve_mh_count, SUN_CLS, "resolve_MethodHandle_count");
1483 NEWPERFEVENTCOUNTER(_perf_resolve_mt_count, SUN_CLS, "resolve_MethodType_count");
1484 }
1485 }
1486
1487 // lookup java library entry points
1488 load_java_library();
1489 // jimage library entry points are loaded below, in lookup_vm_options
1490 setup_bootstrap_search_path(THREAD);
1491 }
1492
1493 // Lookup VM options embedded in the modules jimage file
1494 char* ClassLoader::lookup_vm_options() {
1495 char modules_path[JVM_MAXPATHLEN];
1496 const char* fileSep = os::file_separator();
1497
1498 // Initialize jimage library entry points
1499 load_jimage_library();
1500
1501 jio_snprintf(modules_path, JVM_MAXPATHLEN, "%s%slib%smodules", Arguments::get_java_home(), fileSep, fileSep);
1502 if (jimage_open(modules_path)) {
1503 // Special case where we lookup the options string *before* set_preview_mode() is called.
1504 // Since VM arguments have not been parsed, and the ClassPathImageEntry singleton
1505 // has not been created yet, we access the JImage file directly in non-preview mode.
1506 jlong size;
1507 JImageLocationRef location =
1508 jimage_find_resource(JAVA_BASE_NAME, "jdk/internal/vm/options", /* is_preview */ false, &size);
1509 if (location != 0) {
1510 char* options = NEW_C_HEAP_ARRAY(char, size+1, mtClass);
1511 (*JImageGetResource)(jimage_non_null(), location, options, size);
1512 options[size] = '\0';
1513 return options;
1514 }
1515 }
1516 return nullptr;
1517 }
1518
1519 // Finishes initializing the JImageFile (if present) by setting the access mode.
1520 void ClassLoader::set_preview_mode(bool enable_preview) {
1521 assert(Preview_mode == PREVIEW_MODE_UNINITIALIZED, "set_preview_mode must not be called twice");
1522 Preview_mode = enable_preview ? PREVIEW_MODE_ENABLE_PREVIEW : PREVIEW_MODE_DEFAULT;
1523 }
1524
1525 bool ClassLoader::is_module_observable(const char* module_name) {
1526 assert(JImageOpen != nullptr, "jimage library should have been opened");
1527 if (!jimage_is_open()) {
1528 struct stat st;
1529 const char *path = get_exploded_module_path(module_name, true);
1530 bool res = os::stat(path, &st) == 0;
1531 FREE_C_HEAP_ARRAY(path);
1532 return res;
1533 }
1534 // We don't expect preview mode (i.e. --enable-preview) to affect module visibility.
1535 jlong size;
1536 return jimage_find_resource(module_name, "module-info.class", /* is_preview */ false, &size) != 0;
1537 }
1538
1539 jlong ClassLoader::classloader_time_ms() {
1540 return UsePerfData ?
1541 Management::ticks_to_ms(_perf_accumulated_time->get_value()) : -1;
1542 }
1543
1544 jlong ClassLoader::class_init_count() {
1545 return UsePerfData ? _perf_classes_inited->get_value() : -1;
1546 }
1547
1548 jlong ClassLoader::class_init_time_ms() {
1549 return UsePerfData ?
1550 Management::ticks_to_ms(_perf_class_init_time->get_value()) : -1;
1551 }
1552
1553 jlong ClassLoader::class_verify_time_ms() {
1554 return UsePerfData ?
1555 Management::ticks_to_ms(_perf_class_verify_time->get_value()) : -1;
1556 }
1557
1558 jlong ClassLoader::class_link_count() {
1559 return UsePerfData ? _perf_classes_linked->get_value() : -1;
1560 }
1561
1562 jlong ClassLoader::class_link_time_ms() {
1563 return UsePerfData ?
1564 Management::ticks_to_ms(_perf_class_link_time->get_value()) : -1;
1565 }
1566
1567 int ClassLoader::compute_Object_vtable() {
1568 // hardwired for JDK1.2 -- would need to duplicate class file parsing
1569 // code to determine actual value from file
1570 // Would be value '11' if finals were in vtable
1571 int JDK_1_2_Object_vtable_size = 5;
1572 return JDK_1_2_Object_vtable_size * vtableEntry::size();
1573 }
1574
1575
1576 void classLoader_init1() {
1577 EXCEPTION_MARK;
1578 ClassLoader::initialize(THREAD);
1579 if (HAS_PENDING_EXCEPTION) {
1580 vm_exit_during_initialization("ClassLoader::initialize() failed unexpectedly");
1581 }
1582 }
1583
1584 // Complete the ClassPathEntry setup for the boot loader
1585 void ClassLoader::classLoader_init2(JavaThread* current) {
1586 // Setup the list of module/path pairs for --patch-module processing
1587 // This must be done after the SymbolTable is created in order
1588 // to use fast_compare on module names instead of a string compare.
1589 if (Arguments::get_patch_mod_prefix() != nullptr) {
1590 setup_patch_mod_entries();
1591 }
1592
1593 // Create the ModuleEntry for java.base (must occur after setup_patch_mod_entries
1594 // to successfully determine if java.base has been patched)
1595 create_javabase();
1596
1597 // Setup the initial java.base/path pair for the exploded build entries.
1598 // As more modules are defined during module system initialization, more
1599 // entries will be added to the exploded build array.
1600 if (!has_jrt_entry()) {
1601 assert(!CDSConfig::is_dumping_archive(), "not supported with exploded module builds");
1602 assert(!CDSConfig::is_using_archive(), "UsedSharedSpaces not supported with exploded module builds");
1603 // Set up the boot loader's _exploded_entries list. Note that this gets
1604 // done before loading any classes, by the same thread that will
1605 // subsequently do the first class load. So, no lock is needed for this.
1606 assert(_exploded_entries == nullptr, "Should only get initialized once");
1607 _exploded_entries = new (mtModule)
1608 GrowableArray<ModuleClassPathList*>(EXPLODED_ENTRY_SIZE, mtModule);
1609 add_to_exploded_build_list(current, vmSymbols::java_base());
1610 }
1611 }
1612
1613 char* ClassLoader::get_canonical_path(const char* orig, Thread* thread) {
1614 assert(orig != nullptr, "bad arguments");
1615 // caller needs to allocate ResourceMark for the following output buffer
1616 char* canonical_path = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, JVM_MAXPATHLEN);
1617 ResourceMark rm(thread);
1618 // os::native_path writes into orig_copy
1619 char* orig_copy = ResourceArea::strdup(thread, orig);
1620 if ((CanonicalizeEntry)(os::native_path(orig_copy), canonical_path, JVM_MAXPATHLEN) < 0) {
1621 return nullptr;
1622 }
1623 return canonical_path;
1624 }
1625
1626 void ClassLoader::create_javabase() {
1627 JavaThread* current = JavaThread::current();
1628
1629 // Create java.base's module entry for the boot
1630 // class loader prior to loading j.l.Object.
1631 ClassLoaderData* null_cld = ClassLoaderData::the_null_class_loader_data();
1632
1633 // Get module entry table
1634 ModuleEntryTable* null_cld_modules = null_cld->modules();
1635 if (null_cld_modules == nullptr) {
1636 vm_exit_during_initialization("No ModuleEntryTable for the boot class loader");
1637 }
1638
1639 {
1640 MutexLocker ml(current, Module_lock);
1641 if (ModuleEntryTable::javabase_moduleEntry() == nullptr) { // may have been inited by CDS.
1642 ModuleEntry* jb_module = null_cld_modules->locked_create_entry(Handle(),
1643 false, vmSymbols::java_base(), nullptr, nullptr, null_cld);
1644 if (jb_module == nullptr) {
1645 vm_exit_during_initialization("Unable to create ModuleEntry for " JAVA_BASE_NAME);
1646 }
1647 ModuleEntryTable::set_javabase_moduleEntry(jb_module);
1648 }
1649 }
1650 }
1651
1652 // Please keep following two functions at end of this file. With them placed at top or in middle of the file,
1653 // they could get inlined by aggressive compiler, an unknown trick, see bug 6966589.
1654 void PerfClassTraceTime::initialize() {
1655 if (!UsePerfData) return;
1656
1657 if (_eventp != nullptr) {
1658 // increment the event counter
1659 _eventp->inc();
1660 }
1661
1662 // stop the current active thread-local timer to measure inclusive time
1663 _prev_active_event = -1;
1664 for (int i=0; i < EVENT_TYPE_COUNT; i++) {
1665 if (_timers[i].is_active()) {
1666 assert(_prev_active_event == -1, "should have only one active timer");
1667 _prev_active_event = i;
1668 _timers[i].stop();
1669 }
1670 }
1671
1672 if (_recursion_counters == nullptr || (_recursion_counters[_event_type])++ == 0) {
1673 // start the inclusive timer if not recursively called
1674 _t.start();
1675 }
1676
1677 // start thread-local timer of the given event type
1678 if (!_timers[_event_type].is_active()) {
1679 _timers[_event_type].start();
1680 }
1681 }
1682
1683 PerfClassTraceTime::~PerfClassTraceTime() {
1684 if (!UsePerfData) return;
1685
1686 // stop the thread-local timer as the event completes
1687 // and resume the thread-local timer of the event next on the stack
1688 _timers[_event_type].stop();
1689 jlong selftime = _timers[_event_type].ticks();
1690
1691 if (_prev_active_event >= 0) {
1692 _timers[_prev_active_event].start();
1693 }
1694
1695 if (_recursion_counters != nullptr && --(_recursion_counters[_event_type]) > 0) return;
1696
1697 // increment the counters only on the leaf call
1698 _t.stop();
1699 _timep->inc(_t.ticks());
1700 if (_selftimep != nullptr) {
1701 _selftimep->inc(selftime);
1702 }
1703 // add all class loading related event selftime to the accumulated time counter
1704 ClassLoader::perf_accumulated_time()->inc(selftime);
1705
1706 // reset the timer
1707 _timers[_event_type].reset();
1708 }