1 /*
2 * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "cds/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 "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/timer.hpp"
73 #include "runtime/vm_version.hpp"
74 #include "services/management.hpp"
75 #include "services/threadService.hpp"
76 #include "utilities/checkedCast.hpp"
77 #include "utilities/classpathStream.hpp"
78 #include "utilities/events.hpp"
79 #include "utilities/macros.hpp"
80 #include "utilities/ostream.hpp"
81 #include "utilities/utf8.hpp"
82
83 #include <ctype.h>
84 #include <stdlib.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 // JImageMode status to control preview behaviour. JImage_file is unusable
103 // for normal lookup until (JImage_mode != JIMAGE_MODE_UNINITIALIZED).
104 enum JImageMode {
105 JIMAGE_MODE_UNINITIALIZED = 0,
106 JIMAGE_MODE_DEFAULT = 1,
107 JIMAGE_MODE_ENABLE_PREVIEW = 2
108 };
109 static JImageMode JImage_mode = JIMAGE_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
140 PerfCounter* ClassLoader::_perf_resolve_indy_time = nullptr;
141 PerfCounter* ClassLoader::_perf_resolve_invokehandle_time = nullptr;
142 PerfCounter* ClassLoader::_perf_resolve_mh_time = nullptr;
143 PerfCounter* ClassLoader::_perf_resolve_mt_time = nullptr;
144
145 PerfCounter* ClassLoader::_perf_resolve_indy_count = nullptr;
146 PerfCounter* ClassLoader::_perf_resolve_invokehandle_count = nullptr;
147 PerfCounter* ClassLoader::_perf_resolve_mh_count = nullptr;
148 PerfCounter* ClassLoader::_perf_resolve_mt_count = nullptr;
149
150 void ClassLoader::print_counters(outputStream *st) {
151 st->print_cr("ClassLoader:");
152 st->print_cr(" clinit: " JLONG_FORMAT "ms / " JLONG_FORMAT " events", ClassLoader::class_init_time_ms(), ClassLoader::class_init_count());
153 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());
154 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());
155 st->print_cr(" resolve...");
156 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());
157 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());
158 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());
159 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());
160 st->cr();
161 }
162
163 GrowableArray<ModuleClassPathList*>* ClassLoader::_patch_mod_entries = nullptr;
164 GrowableArray<ModuleClassPathList*>* ClassLoader::_exploded_entries = nullptr;
165 ClassPathImageEntry* ClassLoader::_jrt_entry = nullptr;
166
167 ClassPathEntry* volatile ClassLoader::_first_append_entry_list = nullptr;
168 ClassPathEntry* volatile ClassLoader::_last_append_entry = nullptr;
169
170 // helper routines
171 #if INCLUDE_CDS
172 static bool string_starts_with(const char* str, const char* str_to_find) {
173 size_t str_len = strlen(str);
174 size_t str_to_find_len = strlen(str_to_find);
175 if (str_to_find_len > str_len) {
176 return false;
177 }
178 return (strncmp(str, str_to_find, str_to_find_len) == 0);
179 }
180 #endif
181
182 bool ClassLoader::string_ends_with(const char* str, const char* str_to_find) {
183 size_t str_len = strlen(str);
184 size_t str_to_find_len = strlen(str_to_find);
185 if (str_to_find_len > str_len) {
186 return false;
187 }
188 return (strncmp(str + (str_len - str_to_find_len), str_to_find, str_to_find_len) == 0);
189 }
190
191 // Used to obtain the package name from a fully qualified class name.
192 Symbol* ClassLoader::package_from_class_name(const Symbol* name, bool* bad_class_name) {
193 if (name == nullptr) {
194 if (bad_class_name != nullptr) {
195 *bad_class_name = true;
196 }
197 return nullptr;
198 }
199
200 int utf_len = name->utf8_length();
201 const jbyte* base = (const jbyte*)name->base();
202 const jbyte* start = base;
203 const jbyte* end = UTF8::strrchr(start, utf_len, JVM_SIGNATURE_SLASH);
204 if (end == nullptr) {
205 return nullptr;
206 }
207 // Skip over '['s
208 if (*start == JVM_SIGNATURE_ARRAY) {
209 do {
210 start++;
211 } while (start < end && *start == JVM_SIGNATURE_ARRAY);
212
213 // Fully qualified class names should not contain a 'L'.
214 // Set bad_class_name to true to indicate that the package name
215 // could not be obtained due to an error condition.
216 // In this situation, is_same_class_package returns false.
217 if (*start == JVM_SIGNATURE_CLASS) {
218 if (bad_class_name != nullptr) {
219 *bad_class_name = true;
220 }
221 return nullptr;
222 }
223 }
224 // A class name could have just the slash character in the name,
225 // in which case start > end
226 if (start >= end) {
227 // No package name
228 if (bad_class_name != nullptr) {
229 *bad_class_name = true;
230 }
231 return nullptr;
232 }
233 return SymbolTable::new_symbol(name, pointer_delta_as_int(start, base), pointer_delta_as_int(end, base));
234 }
235
236 // --------------------------------
237 // The following jimage_xxx static functions encapsulate all JImage_file and JImage_mode access.
238 // This is done to make it easy to reason about the JImage file state (exists vs initialized etc.).
239
240 // Opens the named JImage file and sets the JImage file reference.
241 // Returns true if opening the JImage file was successful (see also jimage_exists()).
242 static bool jimage_open(const char* modules_path) {
243 // Currently 'error' is not set to anything useful, so ignore it here.
244 jint error;
245 JImage_file = (*JImageOpen)(modules_path, &error);
246 return JImage_file != nullptr;
247 }
248
249 // Closes and clears the JImage file reference (this will only be called during shutdown).
250 static void jimage_close() {
251 if (JImage_file != nullptr) {
252 (*JImageClose)(JImage_file);
253 JImage_file = nullptr;
254 }
255 }
256
257 // Returns whether a JImage file was opened (but NOT whether it was initialized yet).
258 static bool jimage_exists() {
259 return JImage_file != nullptr;
260 }
261
262 // Returns the JImage file reference (which may or may not be initialized).
263 static JImageFile* jimage_non_null() {
264 assert(jimage_exists(), "should have been opened by ClassLoader::lookup_vm_options "
265 "and remained throughout normal JVM lifetime");
266 return JImage_file;
267 }
268
269 // Called once to set the access mode for resource (i.e. preview or non-preview) before
270 // general resource lookup can occur.
271 static void jimage_init(bool enable_preview) {
272 assert(JImage_mode == JIMAGE_MODE_UNINITIALIZED, "jimage_init must not be called twice");
273 JImage_mode = enable_preview ? JIMAGE_MODE_ENABLE_PREVIEW : JIMAGE_MODE_DEFAULT;
274 }
275
276 // Returns true if jimage_init() has been called. Once the JImage file is initialized,
277 // jimage_is_preview_enabled() can be called to correctly determine the access mode.
278 static bool jimage_is_initialized() {
279 return jimage_exists() && JImage_mode != JIMAGE_MODE_UNINITIALIZED;
280 }
281
282 // Returns the access mode for an initialized JImage file (reflects --enable-preview).
283 static bool jimage_is_preview_enabled() {
284 assert(jimage_is_initialized(), "jimage is not initialized");
285 return JImage_mode == JIMAGE_MODE_ENABLE_PREVIEW;
286 }
287
288 // Looks up the location of a named JImage resource. This "raw" lookup function allows
289 // the preview mode to be manually specified, so must not be accessible outside this
290 // class. ClassPathImageEntry manages all calls for resources after startup is complete.
291 static JImageLocationRef jimage_find_resource(const char* module_name,
292 const char* file_name,
293 bool is_preview,
294 jlong *size) {
295 return ((*JImageFindResource)(jimage_non_null(),
296 module_name,
297 file_name,
298 is_preview,
299 size));
300 }
301 // --------------------------------
302
303 // Given a fully qualified package name, find its defining package in the class loader's
304 // package entry table.
305 PackageEntry* ClassLoader::get_package_entry(Symbol* pkg_name, ClassLoaderData* loader_data) {
306 if (pkg_name == nullptr) {
307 return nullptr;
308 }
309 PackageEntryTable* pkgEntryTable = loader_data->packages();
310 return pkgEntryTable->lookup_only(pkg_name);
311 }
312
313 const char* ClassPathEntry::copy_path(const char* path) {
314 char* copy = NEW_C_HEAP_ARRAY(char, strlen(path)+1, mtClass);
315 strcpy(copy, path);
316 return copy;
317 }
318
319 ClassPathDirEntry::~ClassPathDirEntry() {
320 FREE_C_HEAP_ARRAY(char, _dir);
321 }
322
323 ClassFileStream* ClassPathDirEntry::open_stream(JavaThread* current, const char* name) {
324 // construct full path name
325 assert((_dir != nullptr) && (name != nullptr), "sanity");
326 size_t path_len = strlen(_dir) + strlen(name) + strlen(os::file_separator()) + 1;
327 char* path = NEW_RESOURCE_ARRAY_IN_THREAD(current, char, path_len);
328 int len = jio_snprintf(path, path_len, "%s%s%s", _dir, os::file_separator(), name);
329 assert(len == (int)(path_len - 1), "sanity");
330 // check if file exists
331 struct stat st;
332 if (os::stat(path, &st) == 0) {
333 // found file, open it
334 int file_handle = os::open(path, 0, 0);
335 if (file_handle != -1) {
336 // read contents into resource array
337 u1* buffer = NEW_RESOURCE_ARRAY_IN_THREAD(current, u1, st.st_size);
338 size_t num_read = ::read(file_handle, (char*) buffer, st.st_size);
339 // close file
340 ::close(file_handle);
341 // construct ClassFileStream
342 if (num_read == (size_t)st.st_size) {
343 if (UsePerfData) {
344 ClassLoader::perf_sys_classfile_bytes_read()->inc(num_read);
345 }
346 #ifdef ASSERT
347 // Freeing path is a no-op here as buffer prevents it from being reclaimed. But we keep it for
348 // debug builds so that we guard against use-after-free bugs.
349 FREE_RESOURCE_ARRAY_IN_THREAD(current, char, path, path_len);
350 #endif
351 // We don't verify the length of the classfile stream fits in an int, but this is the
352 // bootloader so we have control of this.
353 // Resource allocated
354 return new ClassFileStream(buffer,
355 checked_cast<int>(st.st_size),
356 _dir);
357 }
358 }
359 }
360 FREE_RESOURCE_ARRAY_IN_THREAD(current, char, path, path_len);
361 return nullptr;
362 }
363
364 ClassPathZipEntry::ClassPathZipEntry(jzfile* zip, const char* zip_name) : ClassPathEntry() {
365 _zip = zip;
366 _zip_name = copy_path(zip_name);
367 }
368
369 ClassPathZipEntry::~ClassPathZipEntry() {
370 ZipLibrary::close(_zip);
371 FREE_C_HEAP_ARRAY(char, _zip_name);
372 }
373
374 bool ClassPathZipEntry::has_entry(JavaThread* current, const char* name) {
375 ThreadToNativeFromVM ttn(current);
376 // check whether zip archive contains name
377 jint name_len;
378 jint filesize;
379 jzentry* entry = ZipLibrary::find_entry(_zip, name, &filesize, &name_len);
380 if (entry == nullptr) {
381 return false;
382 } else {
383 ZipLibrary::free_entry(_zip, entry);
384 return true;
385 }
386 }
387
388 u1* ClassPathZipEntry::open_entry(JavaThread* current, const char* name, jint* filesize, bool nul_terminate) {
389 // enable call to C land
390 ThreadToNativeFromVM ttn(current);
391 // check whether zip archive contains name
392 jint name_len;
393 jzentry* entry = ZipLibrary::find_entry(_zip, name, filesize, &name_len);
394 if (entry == nullptr) return nullptr;
395 u1* buffer;
396 char name_buf[128];
397 char* filename;
398 if (name_len < 128) {
399 filename = name_buf;
400 } else {
401 filename = NEW_RESOURCE_ARRAY(char, name_len + 1);
402 }
403
404 // read contents into resource array
405 size_t size = (uint32_t)(*filesize);
406 if (nul_terminate) {
407 if (sizeof(size) == sizeof(uint32_t) && size == UINT_MAX) {
408 return nullptr; // 32-bit integer overflow will occur.
409 }
410 size++;
411 }
412 buffer = NEW_RESOURCE_ARRAY(u1, size);
413 if (!ZipLibrary::read_entry(_zip, entry, buffer, filename)) {
414 return nullptr;
415 }
416
417 // return result
418 if (nul_terminate) {
419 buffer[size - 1] = 0;
420 }
421 return buffer;
422 }
423
424 ClassFileStream* ClassPathZipEntry::open_stream(JavaThread* current, const char* name) {
425 jint filesize;
426 u1* buffer = open_entry(current, name, &filesize, false);
427 if (buffer == nullptr) {
428 return nullptr;
429 }
430 if (UsePerfData) {
431 ClassLoader::perf_sys_classfile_bytes_read()->inc(filesize);
432 }
433 // Resource allocated
434 return new ClassFileStream(buffer,
435 filesize,
436 _zip_name);
437 }
438
439 DEBUG_ONLY(ClassPathImageEntry* ClassPathImageEntry::_singleton = nullptr;)
440
441 void ClassPathImageEntry::close_jimage() {
442 jimage_close();
443 }
444
445 ClassPathImageEntry::ClassPathImageEntry(const char* name) :
446 ClassPathEntry() {
447 guarantee(jimage_is_initialized(), "jimage is not initialized");
448 guarantee(name != nullptr, "jimage file name is null");
449
450 assert(_singleton == nullptr, "VM supports only one jimage");
451 DEBUG_ONLY(_singleton = this);
452 size_t len = strlen(name) + 1;
453 _name = copy_path(name);
454 }
455
456 ClassFileStream* ClassPathImageEntry::open_stream(JavaThread* current, const char* name) {
457 return open_stream_for_loader(current, name, ClassLoaderData::the_null_class_loader_data());
458 }
459
460 // For a class in a named module, look it up in the jimage file using this syntax:
461 // /<module-name>/<package-name>/<base-class>
462 //
463 // Assumptions:
464 // 1. There are no unnamed modules in the jimage file.
465 // 2. A package is in at most one module in the jimage file.
466 //
467 ClassFileStream* ClassPathImageEntry::open_stream_for_loader(JavaThread* current, const char* name, ClassLoaderData* loader_data) {
468 bool is_preview = jimage_is_preview_enabled();
469
470 jlong size;
471 JImageLocationRef location = jimage_find_resource("", name, is_preview, &size);
472
473 if (location == 0) {
474 TempNewSymbol class_name = SymbolTable::new_symbol(name);
475 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
476
477 if (pkg_name != nullptr) {
478 if (!Universe::is_module_initialized()) {
479 location = jimage_find_resource(JAVA_BASE_NAME, name, is_preview, &size);
480 } else {
481 PackageEntry* package_entry = ClassLoader::get_package_entry(pkg_name, loader_data);
482 if (package_entry != nullptr) {
483 ResourceMark rm(current);
484 // Get the module name
485 ModuleEntry* module = package_entry->module();
486 assert(module != nullptr, "Boot classLoader package missing module");
487 assert(module->is_named(), "Boot classLoader package is in unnamed module");
488 const char* module_name = module->name()->as_C_string();
489 if (module_name != nullptr) {
490 location = jimage_find_resource(module_name, name, is_preview, &size);
491 }
492 }
493 }
494 }
495 }
496 if (location != 0) {
497 if (UsePerfData) {
498 ClassLoader::perf_sys_classfile_bytes_read()->inc(size);
499 }
500 char* data = NEW_RESOURCE_ARRAY(char, size);
501 (*JImageGetResource)(jimage_non_null(), location, data, size);
502 // Resource allocated
503 assert(this == ClassLoader::get_jrt_entry(), "must be");
504 return new ClassFileStream((u1*)data,
505 checked_cast<int>(size),
506 _name,
507 true); // from_boot_loader_modules_image
508 }
509
510 return nullptr;
511 }
512
513 bool ClassPathImageEntry::is_modules_image() const {
514 assert(this == _singleton, "VM supports a single jimage");
515 assert(this == ClassLoader::get_jrt_entry(), "must be used for jrt entry");
516 return true;
517 }
518
519 ModuleClassPathList::ModuleClassPathList(Symbol* module_name) {
520 _module_name = module_name;
521 _module_first_entry = nullptr;
522 _module_last_entry = nullptr;
523 }
524
525 ModuleClassPathList::~ModuleClassPathList() {
526 // Clean out each ClassPathEntry on list
527 ClassPathEntry* e = _module_first_entry;
528 while (e != nullptr) {
529 ClassPathEntry* next_entry = e->next();
530 delete e;
531 e = next_entry;
532 }
533 }
534
535 void ModuleClassPathList::add_to_list(ClassPathEntry* new_entry) {
536 if (new_entry != nullptr) {
537 if (_module_last_entry == nullptr) {
538 _module_first_entry = _module_last_entry = new_entry;
539 } else {
540 _module_last_entry->set_next(new_entry);
541 _module_last_entry = new_entry;
542 }
543 }
544 }
545
546 void ClassLoader::trace_class_path(const char* msg, const char* name) {
547 LogTarget(Info, class, path) lt;
548 if (lt.is_enabled()) {
549 LogStream ls(lt);
550 if (msg) {
551 ls.print("%s", msg);
552 }
553 if (name) {
554 if (strlen(name) < 256) {
555 ls.print("%s", name);
556 } else {
557 // For very long paths, we need to print each character separately,
558 // as print_cr() has a length limit
559 while (name[0] != '\0') {
560 ls.print("%c", name[0]);
561 name++;
562 }
563 }
564 }
565 ls.cr();
566 }
567 }
568
569 void ClassLoader::setup_bootstrap_search_path(JavaThread* current) {
570 const char* bootcp = Arguments::get_boot_class_path();
571 assert(bootcp != nullptr, "Boot class path must not be nullptr");
572 if (PrintSharedArchiveAndExit) {
573 // Don't print bootcp - this is the bootcp of this current VM process, not necessarily
574 // the same as the boot classpath of the shared archive.
575 } else {
576 trace_class_path("bootstrap loader class path=", bootcp);
577 }
578 setup_bootstrap_search_path_impl(current, bootcp);
579 }
580
581 void ClassLoader::close_jrt_image() {
582 // Not applicable for exploded builds
583 if (!ClassLoader::has_jrt_entry()) return;
584 _jrt_entry->close_jimage();
585 }
586
587 // Construct the array of module/path pairs as specified to --patch-module
588 // for the boot loader to search ahead of the jimage, if the class being
589 // loaded is defined to a module that has been specified to --patch-module.
590 void ClassLoader::setup_patch_mod_entries() {
591 JavaThread* current = JavaThread::current();
592 GrowableArray<ModulePatchPath*>* patch_mod_args = Arguments::get_patch_mod_prefix();
593 int num_of_entries = patch_mod_args->length();
594
595 // Set up the boot loader's _patch_mod_entries list
596 _patch_mod_entries = new (mtModule) GrowableArray<ModuleClassPathList*>(num_of_entries, mtModule);
597
598 for (int i = 0; i < num_of_entries; i++) {
599 const char* module_name = (patch_mod_args->at(i))->module_name();
600 Symbol* const module_sym = SymbolTable::new_symbol(module_name);
601 assert(module_sym != nullptr, "Failed to obtain Symbol for module name");
602 ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
603
604 char* class_path = (patch_mod_args->at(i))->path_string();
605 ResourceMark rm(current);
606 ClasspathStream cp_stream(class_path);
607
608 while (cp_stream.has_next()) {
609 const char* path = cp_stream.get_next();
610 struct stat st;
611 if (os::stat(path, &st) == 0) {
612 // File or directory found
613 ClassPathEntry* new_entry = create_class_path_entry(current, path, &st);
614 // If the path specification is valid, enter it into this module's list
615 if (new_entry != nullptr) {
616 module_cpl->add_to_list(new_entry);
617 }
618 }
619 }
620
621 // Record the module into the list of --patch-module entries only if
622 // valid ClassPathEntrys have been created
623 if (module_cpl->module_first_entry() != nullptr) {
624 _patch_mod_entries->push(module_cpl);
625 }
626 }
627 }
628
629 // Determine whether the module has been patched via the command-line
630 // option --patch-module
631 bool ClassLoader::is_in_patch_mod_entries(Symbol* module_name) {
632 if (_patch_mod_entries != nullptr && _patch_mod_entries->is_nonempty()) {
633 int table_len = _patch_mod_entries->length();
634 for (int i = 0; i < table_len; i++) {
635 ModuleClassPathList* patch_mod = _patch_mod_entries->at(i);
636 if (module_name->fast_compare(patch_mod->module_name()) == 0) {
637 return true;
638 }
639 }
640 }
641 return false;
642 }
643
644 // Set up the _jrt_entry if present and boot append path
645 void ClassLoader::setup_bootstrap_search_path_impl(JavaThread* current, const char *class_path) {
646 ResourceMark rm(current);
647 ClasspathStream cp_stream(class_path);
648 bool set_base_piece = true;
649
650 #if INCLUDE_CDS
651 if (CDSConfig::is_dumping_archive()) {
652 if (!Arguments::has_jimage()) {
653 vm_exit_during_initialization("CDS is not supported in exploded JDK build", nullptr);
654 }
655 }
656 #endif
657
658 while (cp_stream.has_next()) {
659 const char* path = cp_stream.get_next();
660
661 if (set_base_piece) {
662 // The first time through the bootstrap_search setup, it must be determined
663 // what the base or core piece of the boot loader search is. Either a java runtime
664 // image is present or this is an exploded module build situation.
665 assert(string_ends_with(path, MODULES_IMAGE_NAME) || string_ends_with(path, JAVA_BASE_NAME),
666 "Incorrect boot loader search path, no java runtime image or " JAVA_BASE_NAME " exploded build");
667 struct stat st;
668 if (os::stat(path, &st) == 0) {
669 // Directory found
670 if (jimage_exists()) {
671 assert(Arguments::has_jimage(), "sanity check");
672 const char* canonical_path = get_canonical_path(path, current);
673 assert(canonical_path != nullptr, "canonical_path issue");
674
675 // Hand over lifecycle control of the JImage file to the _jrt_entry singleton
676 // (see ClassPathImageEntry::close_jimage). The image must be initialized by now.
677 _jrt_entry = new ClassPathImageEntry(canonical_path);
678 assert(_jrt_entry != nullptr && _jrt_entry->is_modules_image(), "No java runtime image present");
679 } // else it's an exploded build.
680 } else {
681 // If path does not exist, exit
682 vm_exit_during_initialization("Unable to establish the boot loader search path", path);
683 }
684 set_base_piece = false;
685 } else {
686 // Every entry on the boot class path after the initial base piece,
687 // which is set by os::set_boot_path(), is considered an appended entry.
688 update_class_path_entry_list(current, path);
689 }
690 }
691 }
692
693 // Gets the exploded path for the named module. The memory for the path
694 // is allocated on the C heap if `c_heap` is true otherwise in the resource area.
695 static const char* get_exploded_module_path(const char* module_name, bool c_heap) {
696 const char *home = Arguments::get_java_home();
697 const char file_sep = os::file_separator()[0];
698 // 10 represents the length of "modules" + 2 file separators + \0
699 size_t len = strlen(home) + strlen(module_name) + 10;
700 char *path = c_heap ? NEW_C_HEAP_ARRAY(char, len, mtModule) : NEW_RESOURCE_ARRAY(char, len);
701 jio_snprintf(path, len, "%s%cmodules%c%s", home, file_sep, file_sep, module_name);
702 return path;
703 }
704
705 // During an exploded modules build, each module defined to the boot loader
706 // will be added to the ClassLoader::_exploded_entries array.
707 void ClassLoader::add_to_exploded_build_list(JavaThread* current, Symbol* module_sym) {
708 assert(!ClassLoader::has_jrt_entry(), "Exploded build not applicable");
709 assert(_exploded_entries != nullptr, "_exploded_entries was not initialized");
710
711 // Find the module's symbol
712 ResourceMark rm(current);
713 const char *module_name = module_sym->as_C_string();
714 const char *path = get_exploded_module_path(module_name, false);
715
716 struct stat st;
717 if (os::stat(path, &st) == 0) {
718 // Directory found
719 ClassPathEntry* new_entry = create_class_path_entry(current, path, &st);
720
721 // If the path specification is valid, enter it into this module's list.
722 // There is no need to check for duplicate modules in the exploded entry list,
723 // since no two modules with the same name can be defined to the boot loader.
724 // This is checked at module definition time in Modules::define_module.
725 if (new_entry != nullptr) {
726 ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
727 module_cpl->add_to_list(new_entry);
728 {
729 MutexLocker ml(current, Module_lock);
730 _exploded_entries->push(module_cpl);
731 }
732 log_info(class, load)("path: %s", path);
733 }
734 }
735 }
736
737 jzfile* ClassLoader::open_zip_file(const char* canonical_path, char** error_msg, JavaThread* thread) {
738 // enable call to C land
739 ThreadToNativeFromVM ttn(thread);
740 HandleMark hm(thread);
741 return ZipLibrary::open(canonical_path, error_msg);
742 }
743
744 ClassPathEntry* ClassLoader::create_class_path_entry(JavaThread* current,
745 const char *path, const struct stat* st) {
746 ClassPathEntry* new_entry = nullptr;
747 if ((st->st_mode & S_IFMT) == S_IFREG) {
748 ResourceMark rm(current);
749 // Regular file, should be a zip file
750 // Canonicalized filename
751 const char* canonical_path = get_canonical_path(path, current);
752 if (canonical_path == nullptr) {
753 return nullptr;
754 }
755 char* error_msg = nullptr;
756 jzfile* zip = open_zip_file(canonical_path, &error_msg, current);
757 if (zip != nullptr && error_msg == nullptr) {
758 new_entry = new ClassPathZipEntry(zip, path);
759 } else {
760 return nullptr;
761 }
762 log_info(class, path)("opened: %s", path);
763 log_info(class, load)("opened: %s", path);
764 } else {
765 // Directory
766 new_entry = new ClassPathDirEntry(path);
767 log_info(class, load)("path: %s", path);
768 }
769 return new_entry;
770 }
771
772
773 // Create a class path zip entry for a given path (return null if not found
774 // or zip/JAR file cannot be opened)
775 ClassPathZipEntry* ClassLoader::create_class_path_zip_entry(const char *path) {
776 // check for a regular file
777 struct stat st;
778 if (os::stat(path, &st) == 0) {
779 if ((st.st_mode & S_IFMT) == S_IFREG) {
780 JavaThread* thread = JavaThread::current();
781 ResourceMark rm(thread);
782 const char* canonical_path = get_canonical_path(path, thread);
783 if (canonical_path != nullptr) {
784 char* error_msg = nullptr;
785 jzfile* zip = open_zip_file(canonical_path, &error_msg, thread);
786 if (zip != nullptr && error_msg == nullptr) {
787 // create using canonical path
788 return new ClassPathZipEntry(zip, canonical_path);
789 }
790 }
791 }
792 }
793 return nullptr;
794 }
795
796 // The boot append entries are added with a lock, and read lock free.
797 void ClassLoader::add_to_boot_append_entries(ClassPathEntry *new_entry) {
798 if (new_entry != nullptr) {
799 MutexLocker ml(Bootclasspath_lock, Mutex::_no_safepoint_check_flag);
800 if (_last_append_entry == nullptr) {
801 _last_append_entry = new_entry;
802 assert(first_append_entry() == nullptr, "boot loader's append class path entry list not empty");
803 AtomicAccess::release_store(&_first_append_entry_list, new_entry);
804 } else {
805 _last_append_entry->set_next(new_entry);
806 _last_append_entry = new_entry;
807 }
808 }
809 }
810
811 // Returns true IFF the file/dir exists and the entry was successfully created.
812 bool ClassLoader::update_class_path_entry_list(JavaThread* current, const char *path) {
813 struct stat st;
814 if (os::stat(path, &st) == 0) {
815 // File or directory found
816 ClassPathEntry* new_entry = nullptr;
817 new_entry = create_class_path_entry(current, path, &st);
818 if (new_entry == nullptr) {
819 return false;
820 }
821
822 // Do not reorder the bootclasspath which would break get_system_package().
823 // Add new entry to linked list
824 add_to_boot_append_entries(new_entry);
825 return true;
826 } else {
827 return false;
828 }
829 }
830
831 static void print_module_entry_table(const GrowableArray<ModuleClassPathList*>* const module_list) {
832 ResourceMark rm;
833 int num_of_entries = module_list->length();
834 for (int i = 0; i < num_of_entries; i++) {
835 ClassPathEntry* e;
836 ModuleClassPathList* mpl = module_list->at(i);
837 tty->print("%s=", mpl->module_name()->as_C_string());
838 e = mpl->module_first_entry();
839 while (e != nullptr) {
840 tty->print("%s", e->name());
841 e = e->next();
842 if (e != nullptr) {
843 tty->print("%s", os::path_separator());
844 }
845 }
846 tty->print(" ;");
847 }
848 }
849
850 void ClassLoader::print_bootclasspath() {
851 ClassPathEntry* e;
852 tty->print("[bootclasspath= ");
853
854 // Print --patch-module module/path specifications first
855 if (_patch_mod_entries != nullptr) {
856 print_module_entry_table(_patch_mod_entries);
857 }
858
859 // [jimage | exploded modules build]
860 if (has_jrt_entry()) {
861 // Print the location of the java runtime image
862 tty->print("%s ;", _jrt_entry->name());
863 } else {
864 // Print exploded module build path specifications
865 if (_exploded_entries != nullptr) {
866 print_module_entry_table(_exploded_entries);
867 }
868 }
869
870 // appended entries
871 e = first_append_entry();
872 while (e != nullptr) {
873 tty->print("%s ;", e->name());
874 e = e->next();
875 }
876 tty->print_cr("]");
877 }
878
879 void* ClassLoader::dll_lookup(void* lib, const char* name, const char* path) {
880 void* func = os::dll_lookup(lib, name);
881 if (func == nullptr) {
882 char msg[256] = "";
883 jio_snprintf(msg, sizeof(msg), "Could not resolve \"%s\"", name);
884 vm_exit_during_initialization(msg, path);
885 }
886 return func;
887 }
888
889 void ClassLoader::load_java_library() {
890 assert(CanonicalizeEntry == nullptr, "should not load java library twice");
891 if (is_vm_statically_linked()) {
892 CanonicalizeEntry = CAST_TO_FN_PTR(canonicalize_fn_t, os::lookup_function("JDK_Canonicalize"));
893 assert(CanonicalizeEntry != nullptr, "could not lookup JDK_Canonicalize");
894 return;
895 }
896
897 void *javalib_handle = os::native_java_library();
898 if (javalib_handle == nullptr) {
899 vm_exit_during_initialization("Unable to load java library", nullptr);
900 }
901
902 CanonicalizeEntry = CAST_TO_FN_PTR(canonicalize_fn_t, dll_lookup(javalib_handle, "JDK_Canonicalize", nullptr));
903 assert(CanonicalizeEntry != nullptr, "could not lookup JDK_Canonicalize in java library");
904 }
905
906 void ClassLoader::load_jimage_library() {
907 assert(JImageOpen == nullptr, "should not load jimage library twice");
908
909 if (is_vm_statically_linked()) {
910 JImageOpen = CAST_TO_FN_PTR(JImageOpen_t, os::lookup_function("JIMAGE_Open"));
911 JImageClose = CAST_TO_FN_PTR(JImageClose_t, os::lookup_function("JIMAGE_Close"));
912 JImageFindResource = CAST_TO_FN_PTR(JImageFindResource_t, os::lookup_function("JIMAGE_FindResource"));
913 JImageGetResource = CAST_TO_FN_PTR(JImageGetResource_t, os::lookup_function("JIMAGE_GetResource"));
914 assert(JImageOpen != nullptr && JImageClose != nullptr &&
915 JImageFindResource != nullptr && JImageGetResource != nullptr,
916 "could not lookup all jimage library functions");
917 return;
918 }
919
920 char path[JVM_MAXPATHLEN];
921 char ebuf[1024];
922 void* handle = nullptr;
923 if (os::dll_locate_lib(path, sizeof(path), Arguments::get_dll_dir(), "jimage")) {
924 handle = os::dll_load(path, ebuf, sizeof ebuf);
925 }
926 if (handle == nullptr) {
927 vm_exit_during_initialization("Unable to load jimage library", path);
928 }
929
930 JImageOpen = CAST_TO_FN_PTR(JImageOpen_t, dll_lookup(handle, "JIMAGE_Open", path));
931 JImageClose = CAST_TO_FN_PTR(JImageClose_t, dll_lookup(handle, "JIMAGE_Close", path));
932 JImageFindResource = CAST_TO_FN_PTR(JImageFindResource_t, dll_lookup(handle, "JIMAGE_FindResource", path));
933 JImageGetResource = CAST_TO_FN_PTR(JImageGetResource_t, dll_lookup(handle, "JIMAGE_GetResource", path));
934 assert(JImageOpen != nullptr && JImageClose != nullptr &&
935 JImageFindResource != nullptr && JImageGetResource != nullptr,
936 "could not lookup all jimage library functions in jimage library");
937 }
938
939 int ClassLoader::crc32(int crc, const char* buf, int len) {
940 return ZipLibrary::crc32(crc, (const jbyte*)buf, len);
941 }
942
943 oop ClassLoader::get_system_package(const char* name, TRAPS) {
944 // Look up the name in the boot loader's package entry table.
945 if (name != nullptr) {
946 TempNewSymbol package_sym = SymbolTable::new_symbol(name);
947 // Look for the package entry in the boot loader's package entry table.
948 PackageEntry* package =
949 ClassLoaderData::the_null_class_loader_data()->packages()->lookup_only(package_sym);
950
951 // Return null if package does not exist or if no classes in that package
952 // have been loaded.
953 if (package != nullptr && package->has_loaded_class()) {
954 ModuleEntry* module = package->module();
955 if (module->location() != nullptr) {
956 ResourceMark rm(THREAD);
957 Handle ml = java_lang_String::create_from_str(
958 module->location()->as_C_string(), THREAD);
959 return ml();
960 }
961 // Return entry on boot loader class path.
962 Handle cph = java_lang_String::create_from_str(
963 ClassLoader::classpath_entry(package->classpath_index())->name(), THREAD);
964 return cph();
965 }
966 }
967 return nullptr;
968 }
969
970 objArrayOop ClassLoader::get_system_packages(TRAPS) {
971 ResourceMark rm(THREAD);
972 // List of pointers to PackageEntrys that have loaded classes.
973 PackageEntryTable* pe_table =
974 ClassLoaderData::the_null_class_loader_data()->packages();
975 GrowableArray<PackageEntry*>* loaded_class_pkgs = pe_table->get_system_packages();
976
977 // Allocate objArray and fill with java.lang.String
978 objArrayOop r = oopFactory::new_objArray(vmClasses::String_klass(),
979 loaded_class_pkgs->length(), CHECK_NULL);
980 objArrayHandle result(THREAD, r);
981 for (int x = 0; x < loaded_class_pkgs->length(); x++) {
982 PackageEntry* package_entry = loaded_class_pkgs->at(x);
983 Handle str = java_lang_String::create_from_symbol(package_entry->name(), CHECK_NULL);
984 result->obj_at_put(x, str());
985 }
986 return result();
987 }
988
989 // caller needs ResourceMark
990 const char* ClassLoader::file_name_for_class_name(const char* class_name,
991 int class_name_len) {
992 assert(class_name != nullptr, "invariant");
993 assert((int)strlen(class_name) == class_name_len, "invariant");
994
995 static const char class_suffix[] = ".class";
996 size_t class_suffix_len = sizeof(class_suffix);
997
998 char* const file_name = NEW_RESOURCE_ARRAY(char,
999 class_name_len +
1000 class_suffix_len); // includes term null
1001
1002 strncpy(file_name, class_name, class_name_len);
1003 strncpy(&file_name[class_name_len], class_suffix, class_suffix_len);
1004
1005 return file_name;
1006 }
1007
1008 static ClassPathEntry* find_first_module_cpe(ModuleEntry* mod_entry,
1009 const GrowableArray<ModuleClassPathList*>* const module_list) {
1010 int num_of_entries = module_list->length();
1011 const Symbol* class_module_name = mod_entry->name();
1012
1013 // Loop through all the modules in either the patch-module or exploded entries looking for module
1014 for (int i = 0; i < num_of_entries; i++) {
1015 ModuleClassPathList* module_cpl = module_list->at(i);
1016 Symbol* module_cpl_name = module_cpl->module_name();
1017
1018 if (module_cpl_name->fast_compare(class_module_name) == 0) {
1019 // Class' module has been located.
1020 return module_cpl->module_first_entry();
1021 }
1022 }
1023 return nullptr;
1024 }
1025
1026
1027 // Search the module list for the class file stream based on the file name and java package
1028 ClassFileStream* ClassLoader::search_module_entries(JavaThread* current,
1029 const GrowableArray<ModuleClassPathList*>* const module_list,
1030 PackageEntry* pkg_entry, // Java package entry derived from the class name
1031 const char* const file_name) {
1032 ClassFileStream* stream = nullptr;
1033
1034 // Find the defining module in the boot loader's module entry table
1035 ModuleEntry* mod_entry = (pkg_entry != nullptr) ? pkg_entry->module() : nullptr;
1036
1037 // If the module system has not defined java.base yet, then
1038 // classes loaded are assumed to be defined to java.base.
1039 // When java.base is eventually defined by the module system,
1040 // all packages of classes that have been previously loaded
1041 // are verified in ModuleEntryTable::verify_javabase_packages().
1042 if (!Universe::is_module_initialized() &&
1043 !ModuleEntryTable::javabase_defined() &&
1044 mod_entry == nullptr) {
1045 mod_entry = ModuleEntryTable::javabase_moduleEntry();
1046 }
1047
1048 // The module must be a named module
1049 ClassPathEntry* e = nullptr;
1050 if (mod_entry != nullptr && mod_entry->is_named()) {
1051 if (module_list == _exploded_entries) {
1052 // The exploded build entries can be added to at any time so a lock is
1053 // needed when searching them.
1054 assert(!ClassLoader::has_jrt_entry(), "Must be exploded build");
1055 MutexLocker ml(current, Module_lock);
1056 e = find_first_module_cpe(mod_entry, module_list);
1057 } else {
1058 e = find_first_module_cpe(mod_entry, module_list);
1059 }
1060 }
1061
1062 // Try to load the class from the module's ClassPathEntry list.
1063 while (e != nullptr) {
1064 stream = e->open_stream(current, file_name);
1065 // No context.check is required since CDS is not supported
1066 // for an exploded modules build or if --patch-module is specified.
1067 if (nullptr != stream) {
1068 return stream;
1069 }
1070 e = e->next();
1071 }
1072 // If the module was located, break out even if the class was not
1073 // located successfully from that module's ClassPathEntry list.
1074 // There will not be another valid entry for that module.
1075 return nullptr;
1076 }
1077
1078 // Called by the boot classloader to load classes
1079 InstanceKlass* ClassLoader::load_class(Symbol* name, PackageEntry* pkg_entry, bool search_append_only, TRAPS) {
1080 assert(name != nullptr, "invariant");
1081
1082 ResourceMark rm(THREAD);
1083 HandleMark hm(THREAD);
1084
1085 const char* const class_name = name->as_C_string();
1086
1087 EventMarkClassLoading m("Loading class %s", class_name);
1088
1089 const char* const file_name = file_name_for_class_name(class_name,
1090 name->utf8_length());
1091 assert(file_name != nullptr, "invariant");
1092
1093 // Lookup stream for parsing .class file
1094 ClassFileStream* stream = nullptr;
1095 s2 classpath_index = 0;
1096 ClassPathEntry* e = nullptr;
1097 bool is_patched = false;
1098
1099 // If search_append_only is true, boot loader visibility boundaries are
1100 // set to be _first_append_entry to the end. This includes:
1101 // [-Xbootclasspath/a]; [jvmti appended entries]
1102 //
1103 // If search_append_only is false, boot loader visibility boundaries are
1104 // set to be the --patch-module entries plus the base piece. This includes:
1105 // [--patch-module=<module>=<file>(<pathsep><file>)*]; [jimage | exploded module build]
1106 //
1107
1108 // Load Attempt #1: --patch-module
1109 // Determine the class' defining module. If it appears in the _patch_mod_entries,
1110 // attempt to load the class from those locations specific to the module.
1111 // Specifications to --patch-module can contain a partial number of classes
1112 // that are part of the overall module definition. So if a particular class is not
1113 // found within its module specification, the search should continue to Load Attempt #2.
1114 // Note: The --patch-module entries are never searched if the boot loader's
1115 // visibility boundary is limited to only searching the append entries.
1116 if (_patch_mod_entries != nullptr && !search_append_only) {
1117 // At CDS dump time, the --patch-module entries are ignored. That means a
1118 // class is still loaded from the runtime image even if it might
1119 // appear in the _patch_mod_entries. The runtime shared class visibility
1120 // check will determine if a shared class is visible based on the runtime
1121 // environment, including the runtime --patch-module setting.
1122 if (!CDSConfig::is_valhalla_preview()) {
1123 // Dynamic dumping requires UseSharedSpaces to be enabled. Since --patch-module
1124 // is not supported with UseSharedSpaces, we can never come here during dynamic dumping.
1125 assert(!CDSConfig::is_dumping_archive(), "CDS doesn't support --patch-module during dumping");
1126 }
1127 if (CDSConfig::is_valhalla_preview() || !CDSConfig::is_dumping_static_archive()) {
1128 stream = search_module_entries(THREAD, _patch_mod_entries, pkg_entry, file_name);
1129 if (stream != nullptr) {
1130 is_patched = true;
1131 }
1132 }
1133 }
1134
1135 // Load Attempt #2: [jimage | exploded build]
1136 if (!search_append_only && (nullptr == stream)) {
1137 if (has_jrt_entry()) {
1138 e = _jrt_entry;
1139 stream = _jrt_entry->open_stream(THREAD, file_name);
1140 } else {
1141 // Exploded build - attempt to locate class in its defining module's location.
1142 assert(_exploded_entries != nullptr, "No exploded build entries present");
1143 assert(!CDSConfig::is_dumping_archive(), "CDS dumping doesn't support exploded build");
1144 stream = search_module_entries(THREAD, _exploded_entries, pkg_entry, file_name);
1145 }
1146 }
1147
1148 // Load Attempt #3: [-Xbootclasspath/a]; [jvmti appended entries]
1149 if (search_append_only && (nullptr == stream)) {
1150 // For the boot loader append path search, the starting classpath_index
1151 // for the appended piece is always 1 to account for either the
1152 // _jrt_entry or the _exploded_entries.
1153 assert(classpath_index == 0, "The classpath_index has been incremented incorrectly");
1154 classpath_index = 1;
1155
1156 e = first_append_entry();
1157 while (e != nullptr) {
1158 stream = e->open_stream(THREAD, file_name);
1159 if (nullptr != stream) {
1160 break;
1161 }
1162 e = e->next();
1163 ++classpath_index;
1164 }
1165 }
1166
1167 if (nullptr == stream) {
1168 return nullptr;
1169 }
1170
1171 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
1172 Handle protection_domain;
1173 ClassLoadInfo cl_info(protection_domain);
1174
1175 InstanceKlass* result = KlassFactory::create_from_stream(stream,
1176 name,
1177 loader_data,
1178 cl_info,
1179 CHECK_NULL);
1180 result->set_classpath_index(classpath_index);
1181 if (is_patched) {
1182 result->set_shared_classpath_index(0);
1183 }
1184 return result;
1185 }
1186
1187 #if INCLUDE_CDS
1188 static const char* skip_uri_protocol(const char* source) {
1189 if (strncmp(source, "file:", 5) == 0) {
1190 // file: protocol path could start with file:/ or file:///
1191 // locate the char after all the forward slashes
1192 int offset = 5;
1193 while (*(source + offset) == '/') {
1194 offset++;
1195 }
1196 source += offset;
1197 // for non-windows platforms, move back one char as the path begins with a '/'
1198 #ifndef _WINDOWS
1199 source -= 1;
1200 #endif
1201 } else if (strncmp(source, "jrt:/", 5) == 0) {
1202 source += 5;
1203 }
1204 return source;
1205 }
1206
1207 static char decode_percent_encoded(const char *str, size_t& index) {
1208 if (str[index] == '%'
1209 && isxdigit(str[index + 1])
1210 && isxdigit(str[index + 2])) {
1211 char hex[3];
1212 hex[0] = str[index + 1];
1213 hex[1] = str[index + 2];
1214 hex[2] = '\0';
1215 index += 2;
1216 return (char) strtol(hex, nullptr, 16);
1217 }
1218 return str[index];
1219 }
1220
1221 char* ClassLoader::uri_to_path(const char* uri) {
1222 const size_t len = strlen(uri) + 1;
1223 char* path = NEW_RESOURCE_ARRAY(char, len);
1224
1225 uri = skip_uri_protocol(uri);
1226
1227 if (strncmp(uri, "//", 2) == 0) {
1228 // Skip the empty "authority" part
1229 uri += 2;
1230 }
1231
1232 #ifdef _WINDOWS
1233 if (uri[0] == '/') {
1234 // Absolute path name on Windows does not begin with a slash
1235 uri += 1;
1236 }
1237 #endif
1238
1239 size_t path_index = 0;
1240 for (size_t i = 0; i < strlen(uri); ++i) {
1241 char decoded = decode_percent_encoded(uri, i);
1242 path[path_index++] = decoded;
1243 }
1244 path[path_index] = '\0';
1245 return path;
1246 }
1247
1248 // Record the shared classpath index and loader type for classes loaded
1249 // by the builtin loaders at dump time.
1250 void ClassLoader::record_result(JavaThread* current, InstanceKlass* ik,
1251 const ClassFileStream* stream, bool redefined) {
1252 assert(CDSConfig::is_dumping_archive(), "sanity");
1253 assert(stream != nullptr, "sanity");
1254
1255 if (ik->is_hidden()) {
1256 record_hidden_class(ik);
1257 return;
1258 }
1259
1260 if (ik->shared_classpath_index() == 0 && ik->defined_by_boot_loader()) {
1261 return;
1262 }
1263
1264 oop loader = ik->class_loader();
1265 char* src = (char*)stream->source();
1266 if (src == nullptr) {
1267 ik->set_shared_classpath_index(-1); // unsupported location
1268 return;
1269 }
1270
1271 if (!SystemDictionaryShared::is_builtin_loader(ik->class_loader_data())) {
1272 // A class loaded by a user-defined classloader.
1273 assert(ik->shared_classpath_index() < 0, "not assigned yet");
1274 ik->set_shared_classpath_index(UNREGISTERED_INDEX);
1275 SystemDictionaryShared::set_shared_class_misc_info(ik, (ClassFileStream*)stream);
1276 return;
1277 }
1278
1279 assert(has_jrt_entry(), "CDS dumping does not support exploded JDK build");
1280
1281 ResourceMark rm(current);
1282 int classpath_index = -1;
1283 bool found_invalid = false;
1284
1285 PackageEntry* pkg_entry = ik->package();
1286
1287 if (!AOTClassLocationConfig::dumptime_is_ready()) {
1288 // The shared path table is set up after module system initialization.
1289 // The path table contains no entry before that. Any classes loaded prior
1290 // to the setup of the shared path table must be from the modules image.
1291 assert(stream->from_boot_loader_modules_image(), "stream must be loaded by boot loader from modules image");
1292 classpath_index = 0;
1293 } else {
1294 // Save the path from the file: protocol or the module name from the jrt: protocol
1295 // if no protocol prefix is found, path is the same as stream->source(). This path
1296 // must be valid since the class has been successfully parsed.
1297 const char* path = ClassLoader::uri_to_path(src);
1298 assert(path != nullptr, "sanity");
1299 AOTClassLocationConfig::dumptime_iterate([&] (AOTClassLocation* cl) {
1300 int i = cl->index();
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 (cl->is_modules_image() && (stream->from_boot_loader_modules_image() || string_starts_with(src, "jrt:"))) {
1304 classpath_index = i;
1305 } else if (os::same_files(cl->path(), path)) {
1306 // If the path (from the class stream source) is the same as the shared
1307 // class or module path, then we have a match.
1308 // src may come from the App/Platform class loaders, which would canonicalize
1309 // the file name. We cannot use strcmp to check for equality against cs->path().
1310 // We must use os::same_files (which is faster than canonicalizing cs->path()).
1311
1312 // null pkg_entry and pkg_entry in an unnamed module implies the class
1313 // is from the -cp or boot loader append path which consists of -Xbootclasspath/a
1314 // and jvmti appended entries.
1315 if ((pkg_entry == nullptr) || (pkg_entry->in_unnamed_module())) {
1316 // Ensure the index is within the -cp range before assigning
1317 // to the classpath_index.
1318 if (SystemDictionary::is_system_class_loader(loader) && cl->from_app_classpath()) {
1319 classpath_index = i;
1320 } else {
1321 if (cl->from_boot_classpath()) {
1322 if (loader != nullptr) {
1323 // Probably loaded by jdk/internal/loader/ClassLoaders$BootClassLoader. Don't archive
1324 // such classes.
1325 found_invalid = true;
1326 } else {
1327 classpath_index = i;
1328 }
1329 }
1330 }
1331 } else {
1332 // A class from a named module from the --module-path. Ensure the index is
1333 // within the --module-path range before assigning to the classpath_index.
1334 if ((pkg_entry != nullptr) && !(pkg_entry->in_unnamed_module()) && cl->from_module_path()) {
1335 classpath_index = i;
1336 }
1337 }
1338 }
1339 if (classpath_index >= 0 || found_invalid) {
1340 return false; // Break the AOTClassLocationConfig::dumptime_iterate() loop.
1341 } else {
1342 return true; // Keep iterating
1343 }
1344 });
1345 }
1346
1347 if (found_invalid) {
1348 assert(classpath_index == -1, "sanity");
1349 }
1350
1351 const char* const class_name = ik->name()->as_C_string();
1352 const char* const file_name = file_name_for_class_name(class_name,
1353 ik->name()->utf8_length());
1354 assert(file_name != nullptr, "invariant");
1355 record_result_for_builtin_loader(checked_cast<s2>(classpath_index), ik, redefined);
1356 }
1357
1358 void ClassLoader::record_result_for_builtin_loader(s2 classpath_index, InstanceKlass* result, bool redefined) {
1359 assert(CDSConfig::is_dumping_archive(), "sanity");
1360
1361 oop loader = result->class_loader();
1362 if (SystemDictionary::is_system_class_loader(loader)) {
1363 AOTClassLocationConfig::dumptime_set_has_app_classes();
1364 } else if (SystemDictionary::is_platform_class_loader(loader)) {
1365 AOTClassLocationConfig::dumptime_set_has_platform_classes();
1366 } else {
1367 precond(loader == nullptr);
1368 }
1369
1370 if (CDSConfig::is_dumping_preimage_static_archive() || CDSConfig::is_dumping_dynamic_archive()) {
1371 if (!AOTClassLocationConfig::dumptime()->is_valid_classpath_index(classpath_index, result)) {
1372 classpath_index = -1;
1373 }
1374 }
1375
1376 AOTClassLocationConfig::dumptime_update_max_used_index(classpath_index);
1377 result->set_shared_classpath_index(classpath_index);
1378 }
1379
1380 void ClassLoader::record_hidden_class(InstanceKlass* ik) {
1381 assert(ik->is_hidden(), "must be");
1382
1383 if (ik->defined_by_other_loaders()) {
1384 // We don't archive hidden classes for non-builtin loaders.
1385 return;
1386 }
1387
1388 if (HeapShared::is_lambda_proxy_klass(ik)) {
1389 InstanceKlass* nest_host = ik->nest_host_not_null();
1390 ik->set_shared_classpath_index(nest_host->shared_classpath_index());
1391 } else if (HeapShared::is_lambda_form_klass(ik)) {
1392 ik->set_shared_classpath_index(0);
1393 } else {
1394 // Generated invoker classes.
1395 if (ik->defined_by_app_loader()) {
1396 ik->set_shared_classpath_index(AOTClassLocationConfig::dumptime()->app_cp_start_index());
1397 } else {
1398 ik->set_shared_classpath_index(0);
1399 }
1400 }
1401 }
1402
1403 void ClassLoader::append_boot_classpath(ClassPathEntry* new_entry) {
1404 if (CDSConfig::is_using_archive()) {
1405 warning("Sharing is only supported for boot loader classes because bootstrap classpath has been appended");
1406 FileMapInfo::current_info()->set_has_platform_or_app_classes(false);
1407 if (DynamicArchive::is_mapped()) {
1408 FileMapInfo::dynamic_info()->set_has_platform_or_app_classes(false);
1409 }
1410 }
1411 add_to_boot_append_entries(new_entry);
1412 }
1413 #endif // INCLUDE_CDS
1414
1415 // Initialize the class loader's access to methods in libzip. Parse and
1416 // process the boot classpath into a list ClassPathEntry objects. Once
1417 // this list has been created, it must not change order (see class PackageInfo)
1418 // it can be appended to and is by jvmti.
1419
1420 void ClassLoader::initialize(TRAPS) {
1421 if (UsePerfData) {
1422 // jvmstat performance counters
1423 NEWPERFTICKCOUNTER(_perf_accumulated_time, SUN_CLS, "time");
1424 NEWPERFTICKCOUNTER(_perf_class_init_time, SUN_CLS, "classInitTime");
1425 NEWPERFTICKCOUNTER(_perf_class_init_selftime, SUN_CLS, "classInitTime.self");
1426 NEWPERFTICKCOUNTER(_perf_class_verify_time, SUN_CLS, "classVerifyTime");
1427 NEWPERFTICKCOUNTER(_perf_class_verify_selftime, SUN_CLS, "classVerifyTime.self");
1428 NEWPERFTICKCOUNTER(_perf_class_link_time, SUN_CLS, "classLinkedTime");
1429 NEWPERFTICKCOUNTER(_perf_class_link_selftime, SUN_CLS, "classLinkedTime.self");
1430 NEWPERFEVENTCOUNTER(_perf_classes_inited, SUN_CLS, "initializedClasses");
1431 NEWPERFEVENTCOUNTER(_perf_classes_linked, SUN_CLS, "linkedClasses");
1432 NEWPERFEVENTCOUNTER(_perf_classes_verified, SUN_CLS, "verifiedClasses");
1433
1434 NEWPERFTICKCOUNTER(_perf_shared_classload_time, SUN_CLS, "sharedClassLoadTime");
1435 NEWPERFTICKCOUNTER(_perf_sys_classload_time, SUN_CLS, "sysClassLoadTime");
1436 NEWPERFTICKCOUNTER(_perf_app_classload_time, SUN_CLS, "appClassLoadTime");
1437 NEWPERFTICKCOUNTER(_perf_app_classload_selftime, SUN_CLS, "appClassLoadTime.self");
1438 NEWPERFEVENTCOUNTER(_perf_app_classload_count, SUN_CLS, "appClassLoadCount");
1439 NEWPERFTICKCOUNTER(_perf_define_appclasses, SUN_CLS, "defineAppClasses");
1440 NEWPERFTICKCOUNTER(_perf_define_appclass_time, SUN_CLS, "defineAppClassTime");
1441 NEWPERFTICKCOUNTER(_perf_define_appclass_selftime, SUN_CLS, "defineAppClassTime.self");
1442 NEWPERFBYTECOUNTER(_perf_app_classfile_bytes_read, SUN_CLS, "appClassBytes");
1443 NEWPERFBYTECOUNTER(_perf_sys_classfile_bytes_read, SUN_CLS, "sysClassBytes");
1444 NEWPERFEVENTCOUNTER(_unsafe_defineClassCallCounter, SUN_CLS, "unsafeDefineClassCalls");
1445 NEWPERFTICKCOUNTER(_perf_secondary_hash_time, SUN_CLS, "secondarySuperHashTime");
1446
1447 if (log_is_enabled(Info, perf, class, link)) {
1448 NEWPERFTICKCOUNTER(_perf_ik_link_methods_time, SUN_CLS, "linkMethodsTime");
1449 NEWPERFTICKCOUNTER(_perf_method_adapters_time, SUN_CLS, "makeAdaptersTime");
1450 NEWPERFEVENTCOUNTER(_perf_ik_link_methods_count, SUN_CLS, "linkMethodsCount");
1451 NEWPERFEVENTCOUNTER(_perf_method_adapters_count, SUN_CLS, "makeAdaptersCount");
1452
1453 NEWPERFTICKCOUNTER(_perf_resolve_indy_time, SUN_CLS, "resolve_invokedynamic_time");
1454 NEWPERFTICKCOUNTER(_perf_resolve_invokehandle_time, SUN_CLS, "resolve_invokehandle_time");
1455 NEWPERFTICKCOUNTER(_perf_resolve_mh_time, SUN_CLS, "resolve_MethodHandle_time");
1456 NEWPERFTICKCOUNTER(_perf_resolve_mt_time, SUN_CLS, "resolve_MethodType_time");
1457
1458 NEWPERFEVENTCOUNTER(_perf_resolve_indy_count, SUN_CLS, "resolve_invokedynamic_count");
1459 NEWPERFEVENTCOUNTER(_perf_resolve_invokehandle_count, SUN_CLS, "resolve_invokehandle_count");
1460 NEWPERFEVENTCOUNTER(_perf_resolve_mh_count, SUN_CLS, "resolve_MethodHandle_count");
1461 NEWPERFEVENTCOUNTER(_perf_resolve_mt_count, SUN_CLS, "resolve_MethodType_count");
1462 }
1463 }
1464
1465 // lookup java library entry points
1466 load_java_library();
1467 // jimage library entry points are loaded below, in lookup_vm_options
1468 setup_bootstrap_search_path(THREAD);
1469 }
1470
1471 // Lookup VM options embedded in the modules jimage file
1472 char* ClassLoader::lookup_vm_options() {
1473 char modules_path[JVM_MAXPATHLEN];
1474 const char* fileSep = os::file_separator();
1475
1476 // Initialize jimage library entry points
1477 load_jimage_library();
1478
1479 jio_snprintf(modules_path, JVM_MAXPATHLEN, "%s%slib%smodules", Arguments::get_java_home(), fileSep, fileSep);
1480 if (jimage_open(modules_path)) {
1481 // Special case where we lookup the options string *before* calling jimage_init().
1482 // Since VM arguments have not been parsed, and the ClassPathImageEntry singleton
1483 // has not been created yet, we access the JImage file directly in non-preview mode.
1484 jlong size;
1485 JImageLocationRef location =
1486 jimage_find_resource(JAVA_BASE_NAME, "jdk/internal/vm/options", /* is_preview */ false, &size);
1487 if (location != 0) {
1488 char *options = NEW_C_HEAP_ARRAY(char, size+1, mtClass);
1489 (*JImageGetResource)(jimage_non_null(), location, options, size);
1490 options[size] = '\0';
1491 return options;
1492 }
1493 }
1494 return nullptr;
1495 }
1496
1497 // Finishes initializing the JImageFile (if present) by setting the access mode.
1498 void ClassLoader::init_jimage(bool enable_preview) {
1499 if (jimage_exists()) {
1500 jimage_init(enable_preview);
1501 }
1502 }
1503
1504 bool ClassLoader::is_module_observable(const char* module_name) {
1505 assert(JImageOpen != nullptr, "jimage library should have been opened");
1506 if (!jimage_exists()) {
1507 struct stat st;
1508 const char *path = get_exploded_module_path(module_name, true);
1509 bool res = os::stat(path, &st) == 0;
1510 FREE_C_HEAP_ARRAY(char, path);
1511 return res;
1512 }
1513 // We don't expect preview mode (i.e. --enable-preview) to affect module visibility.
1514 jlong size;
1515 return jimage_find_resource(module_name, "module-info.class", /* is_preview */ false, &size) != 0;
1516 }
1517
1518 jlong ClassLoader::classloader_time_ms() {
1519 return UsePerfData ?
1520 Management::ticks_to_ms(_perf_accumulated_time->get_value()) : -1;
1521 }
1522
1523 jlong ClassLoader::class_init_count() {
1524 return UsePerfData ? _perf_classes_inited->get_value() : -1;
1525 }
1526
1527 jlong ClassLoader::class_init_time_ms() {
1528 return UsePerfData ?
1529 Management::ticks_to_ms(_perf_class_init_time->get_value()) : -1;
1530 }
1531
1532 jlong ClassLoader::class_verify_time_ms() {
1533 return UsePerfData ?
1534 Management::ticks_to_ms(_perf_class_verify_time->get_value()) : -1;
1535 }
1536
1537 jlong ClassLoader::class_link_count() {
1538 return UsePerfData ? _perf_classes_linked->get_value() : -1;
1539 }
1540
1541 jlong ClassLoader::class_link_time_ms() {
1542 return UsePerfData ?
1543 Management::ticks_to_ms(_perf_class_link_time->get_value()) : -1;
1544 }
1545
1546 int ClassLoader::compute_Object_vtable() {
1547 // hardwired for JDK1.2 -- would need to duplicate class file parsing
1548 // code to determine actual value from file
1549 // Would be value '11' if finals were in vtable
1550 int JDK_1_2_Object_vtable_size = 5;
1551 return JDK_1_2_Object_vtable_size * vtableEntry::size();
1552 }
1553
1554
1555 void classLoader_init1() {
1556 EXCEPTION_MARK;
1557 ClassLoader::initialize(THREAD);
1558 if (HAS_PENDING_EXCEPTION) {
1559 vm_exit_during_initialization("ClassLoader::initialize() failed unexpectedly");
1560 }
1561 }
1562
1563 // Complete the ClassPathEntry setup for the boot loader
1564 void ClassLoader::classLoader_init2(JavaThread* current) {
1565 // Setup the list of module/path pairs for --patch-module processing
1566 // This must be done after the SymbolTable is created in order
1567 // to use fast_compare on module names instead of a string compare.
1568 if (Arguments::get_patch_mod_prefix() != nullptr) {
1569 setup_patch_mod_entries();
1570 }
1571
1572 // Create the ModuleEntry for java.base (must occur after setup_patch_mod_entries
1573 // to successfully determine if java.base has been patched)
1574 create_javabase();
1575
1576 // Setup the initial java.base/path pair for the exploded build entries.
1577 // As more modules are defined during module system initialization, more
1578 // entries will be added to the exploded build array.
1579 if (!has_jrt_entry()) {
1580 assert(!CDSConfig::is_dumping_archive(), "not supported with exploded module builds");
1581 assert(!CDSConfig::is_using_archive(), "UsedSharedSpaces not supported with exploded module builds");
1582 // Set up the boot loader's _exploded_entries list. Note that this gets
1583 // done before loading any classes, by the same thread that will
1584 // subsequently do the first class load. So, no lock is needed for this.
1585 assert(_exploded_entries == nullptr, "Should only get initialized once");
1586 _exploded_entries = new (mtModule)
1587 GrowableArray<ModuleClassPathList*>(EXPLODED_ENTRY_SIZE, mtModule);
1588 add_to_exploded_build_list(current, vmSymbols::java_base());
1589 }
1590 }
1591
1592 char* ClassLoader::get_canonical_path(const char* orig, Thread* thread) {
1593 assert(orig != nullptr, "bad arguments");
1594 // caller needs to allocate ResourceMark for the following output buffer
1595 char* canonical_path = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, JVM_MAXPATHLEN);
1596 ResourceMark rm(thread);
1597 // os::native_path writes into orig_copy
1598 char* orig_copy = ResourceArea::strdup(thread, orig);
1599 if ((CanonicalizeEntry)(os::native_path(orig_copy), canonical_path, JVM_MAXPATHLEN) < 0) {
1600 return nullptr;
1601 }
1602 return canonical_path;
1603 }
1604
1605 void ClassLoader::create_javabase() {
1606 JavaThread* current = JavaThread::current();
1607
1608 // Create java.base's module entry for the boot
1609 // class loader prior to loading j.l.Object.
1610 ClassLoaderData* null_cld = ClassLoaderData::the_null_class_loader_data();
1611
1612 // Get module entry table
1613 ModuleEntryTable* null_cld_modules = null_cld->modules();
1614 if (null_cld_modules == nullptr) {
1615 vm_exit_during_initialization("No ModuleEntryTable for the boot class loader");
1616 }
1617
1618 {
1619 MutexLocker ml(current, Module_lock);
1620 if (ModuleEntryTable::javabase_moduleEntry() == nullptr) { // may have been inited by CDS.
1621 ModuleEntry* jb_module = null_cld_modules->locked_create_entry(Handle(),
1622 false, vmSymbols::java_base(), nullptr, nullptr, null_cld);
1623 if (jb_module == nullptr) {
1624 vm_exit_during_initialization("Unable to create ModuleEntry for " JAVA_BASE_NAME);
1625 }
1626 ModuleEntryTable::set_javabase_moduleEntry(jb_module);
1627 }
1628 }
1629 }
1630
1631 // Please keep following two functions at end of this file. With them placed at top or in middle of the file,
1632 // they could get inlined by aggressive compiler, an unknown trick, see bug 6966589.
1633 void PerfClassTraceTime::initialize() {
1634 if (!UsePerfData) return;
1635
1636 if (_eventp != nullptr) {
1637 // increment the event counter
1638 _eventp->inc();
1639 }
1640
1641 // stop the current active thread-local timer to measure inclusive time
1642 _prev_active_event = -1;
1643 for (int i=0; i < EVENT_TYPE_COUNT; i++) {
1644 if (_timers[i].is_active()) {
1645 assert(_prev_active_event == -1, "should have only one active timer");
1646 _prev_active_event = i;
1647 _timers[i].stop();
1648 }
1649 }
1650
1651 if (_recursion_counters == nullptr || (_recursion_counters[_event_type])++ == 0) {
1652 // start the inclusive timer if not recursively called
1653 _t.start();
1654 }
1655
1656 // start thread-local timer of the given event type
1657 if (!_timers[_event_type].is_active()) {
1658 _timers[_event_type].start();
1659 }
1660 }
1661
1662 PerfClassTraceTime::~PerfClassTraceTime() {
1663 if (!UsePerfData) return;
1664
1665 // stop the thread-local timer as the event completes
1666 // and resume the thread-local timer of the event next on the stack
1667 _timers[_event_type].stop();
1668 jlong selftime = _timers[_event_type].ticks();
1669
1670 if (_prev_active_event >= 0) {
1671 _timers[_prev_active_event].start();
1672 }
1673
1674 if (_recursion_counters != nullptr && --(_recursion_counters[_event_type]) > 0) return;
1675
1676 // increment the counters only on the leaf call
1677 _t.stop();
1678 _timep->inc(_t.ticks());
1679 if (_selftimep != nullptr) {
1680 _selftimep->inc(selftime);
1681 }
1682 // add all class loading related event selftime to the accumulated time counter
1683 ClassLoader::perf_accumulated_time()->inc(selftime);
1684
1685 // reset the timer
1686 _timers[_event_type].reset();
1687 }