1 /*
2 * Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "cds/cds_globals.hpp"
27 #include "cds/cdsConfig.hpp"
28 #include "cds/filemap.hpp"
29 #include "classfile/classFileStream.hpp"
30 #include "classfile/classLoader.inline.hpp"
31 #include "classfile/classLoaderData.inline.hpp"
32 #include "classfile/classLoaderExt.hpp"
33 #include "classfile/classLoadInfo.hpp"
34 #include "classfile/javaClasses.hpp"
35 #include "classfile/moduleEntry.hpp"
36 #include "classfile/modules.hpp"
37 #include "classfile/packageEntry.hpp"
38 #include "classfile/klassFactory.hpp"
39 #include "classfile/symbolTable.hpp"
40 #include "classfile/systemDictionary.hpp"
41 #include "classfile/systemDictionaryShared.hpp"
42 #include "classfile/vmClasses.hpp"
43 #include "classfile/vmSymbols.hpp"
44 #include "compiler/compileBroker.hpp"
45 #include "interpreter/bytecodeStream.hpp"
46 #include "interpreter/oopMapCache.hpp"
47 #include "jimage.hpp"
48 #include "jvm.h"
49 #include "logging/log.hpp"
50 #include "logging/logStream.hpp"
51 #include "logging/logTag.hpp"
52 #include "memory/allocation.inline.hpp"
53 #include "memory/oopFactory.hpp"
54 #include "memory/resourceArea.hpp"
55 #include "memory/universe.hpp"
56 #include "oops/instanceKlass.hpp"
57 #include "oops/instanceRefKlass.hpp"
58 #include "oops/klass.inline.hpp"
59 #include "oops/method.inline.hpp"
60 #include "oops/objArrayOop.inline.hpp"
61 #include "oops/oop.inline.hpp"
62 #include "oops/symbol.hpp"
63 #include "prims/jvm_misc.hpp"
64 #include "runtime/arguments.hpp"
65 #include "runtime/handles.inline.hpp"
66 #include "runtime/init.hpp"
67 #include "runtime/interfaceSupport.inline.hpp"
68 #include "runtime/java.hpp"
69 #include "runtime/javaCalls.hpp"
70 #include "runtime/os.hpp"
71 #include "runtime/perfData.hpp"
72 #include "runtime/threadCritical.hpp"
73 #include "runtime/timer.hpp"
74 #include "runtime/vm_version.hpp"
75 #include "services/management.hpp"
76 #include "services/threadService.hpp"
77 #include "utilities/checkedCast.hpp"
78 #include "utilities/classpathStream.hpp"
79 #include "utilities/events.hpp"
80 #include "utilities/macros.hpp"
81 #include "utilities/ostream.hpp"
82 #include "utilities/utf8.hpp"
83
84 #include <stdlib.h>
85 #include <ctype.h>
86
87 // Entry point in java.dll for path canonicalization
88
89 typedef int (*canonicalize_fn_t)(const char *orig, char *out, int len);
90
91 static canonicalize_fn_t CanonicalizeEntry = nullptr;
92
93 // Entry points for jimage.dll for loading jimage file entries
94
95 static JImageOpen_t JImageOpen = nullptr;
96 static JImageClose_t JImageClose = nullptr;
97 static JImageFindResource_t JImageFindResource = nullptr;
98 static JImageGetResource_t JImageGetResource = nullptr;
99
100 // JimageFile pointer, or null if exploded JDK build.
101 static JImageFile* JImage_file = nullptr;
102
103 // Globals
104
105 PerfCounter* ClassLoader::_perf_accumulated_time = nullptr;
106 PerfCounter* ClassLoader::_perf_classes_inited = nullptr;
107 PerfCounter* ClassLoader::_perf_class_init_time = nullptr;
108 PerfCounter* ClassLoader::_perf_class_init_selftime = nullptr;
109 PerfCounter* ClassLoader::_perf_classes_verified = nullptr;
110 PerfCounter* ClassLoader::_perf_class_verify_time = nullptr;
111 PerfCounter* ClassLoader::_perf_class_verify_selftime = nullptr;
112 PerfCounter* ClassLoader::_perf_classes_linked = nullptr;
113 PerfCounter* ClassLoader::_perf_class_link_time = nullptr;
114 PerfCounter* ClassLoader::_perf_class_link_selftime = nullptr;
115 PerfCounter* ClassLoader::_perf_shared_classload_time = nullptr;
116 PerfCounter* ClassLoader::_perf_sys_classload_time = nullptr;
117 PerfCounter* ClassLoader::_perf_app_classload_time = nullptr;
118 PerfCounter* ClassLoader::_perf_app_classload_selftime = nullptr;
119 PerfCounter* ClassLoader::_perf_app_classload_count = nullptr;
120 PerfCounter* ClassLoader::_perf_define_appclasses = nullptr;
121 PerfCounter* ClassLoader::_perf_define_appclass_time = nullptr;
122 PerfCounter* ClassLoader::_perf_define_appclass_selftime = nullptr;
123 PerfCounter* ClassLoader::_perf_app_classfile_bytes_read = nullptr;
124 PerfCounter* ClassLoader::_perf_sys_classfile_bytes_read = nullptr;
125 PerfCounter* ClassLoader::_perf_ik_link_methods_time = nullptr;
126 PerfCounter* ClassLoader::_perf_method_adapters_time = nullptr;
127 PerfCounter* ClassLoader::_perf_ik_link_methods_count = nullptr;
128 PerfCounter* ClassLoader::_perf_method_adapters_count = nullptr;
129 PerfCounter* ClassLoader::_unsafe_defineClassCallCounter = nullptr;
130 PerfCounter* ClassLoader::_perf_secondary_hash_time = nullptr;
131
132 PerfCounter* ClassLoader::_perf_resolve_indy_time = nullptr;
133 PerfCounter* ClassLoader::_perf_resolve_invokehandle_time = nullptr;
134 PerfCounter* ClassLoader::_perf_resolve_mh_time = nullptr;
135 PerfCounter* ClassLoader::_perf_resolve_mt_time = nullptr;
136
137 PerfCounter* ClassLoader::_perf_resolve_indy_count = nullptr;
138 PerfCounter* ClassLoader::_perf_resolve_invokehandle_count = nullptr;
139 PerfCounter* ClassLoader::_perf_resolve_mh_count = nullptr;
140 PerfCounter* ClassLoader::_perf_resolve_mt_count = nullptr;
141
142 void ClassLoader::print_counters(outputStream *st) {
143 // The counters are only active if the logging is enabled, but
144 // we print to the passed in outputStream as requested.
145 if (log_is_enabled(Info, perf, class, link)) {
146 st->print_cr("ClassLoader:");
147 st->print_cr(" clinit: " JLONG_FORMAT "ms / " JLONG_FORMAT " events", ClassLoader::class_init_time_ms(), ClassLoader::class_init_count());
148 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());
149 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());
150 st->print_cr(" resolve...");
151 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());
152 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());
153 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());
154 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());
155 st->cr();
156 }
157 }
158
159 GrowableArray<ModuleClassPathList*>* ClassLoader::_patch_mod_entries = nullptr;
160 GrowableArray<ModuleClassPathList*>* ClassLoader::_exploded_entries = nullptr;
161 ClassPathEntry* ClassLoader::_jrt_entry = nullptr;
162
163 ClassPathEntry* volatile ClassLoader::_first_append_entry_list = nullptr;
164 ClassPathEntry* volatile ClassLoader::_last_append_entry = nullptr;
165 #if INCLUDE_CDS
166 ClassPathEntry* ClassLoader::_app_classpath_entries = nullptr;
167 ClassPathEntry* ClassLoader::_last_app_classpath_entry = nullptr;
168 ClassPathEntry* ClassLoader::_module_path_entries = nullptr;
169 ClassPathEntry* ClassLoader::_last_module_path_entry = nullptr;
170 #endif
171
172 // helper routines
173 #if INCLUDE_CDS
174 static bool string_starts_with(const char* str, const char* str_to_find) {
175 size_t str_len = strlen(str);
176 size_t str_to_find_len = strlen(str_to_find);
177 if (str_to_find_len > str_len) {
178 return false;
179 }
180 return (strncmp(str, str_to_find, str_to_find_len) == 0);
181 }
182 #endif
183
184 static const char* get_jimage_version_string() {
185 static char version_string[10] = "";
186 if (version_string[0] == '\0') {
187 jio_snprintf(version_string, sizeof(version_string), "%d.%d",
188 VM_Version::vm_major_version(), VM_Version::vm_minor_version());
189 }
190 return (const char*)version_string;
191 }
192
193 bool ClassLoader::string_ends_with(const char* str, const char* str_to_find) {
194 size_t str_len = strlen(str);
195 size_t str_to_find_len = strlen(str_to_find);
196 if (str_to_find_len > str_len) {
197 return false;
198 }
199 return (strncmp(str + (str_len - str_to_find_len), str_to_find, str_to_find_len) == 0);
200 }
201
202 // Used to obtain the package name from a fully qualified class name.
203 Symbol* ClassLoader::package_from_class_name(const Symbol* name, bool* bad_class_name) {
204 if (name == nullptr) {
205 if (bad_class_name != nullptr) {
206 *bad_class_name = true;
207 }
208 return nullptr;
209 }
210
211 int utf_len = name->utf8_length();
212 const jbyte* base = (const jbyte*)name->base();
213 const jbyte* start = base;
214 const jbyte* end = UTF8::strrchr(start, utf_len, JVM_SIGNATURE_SLASH);
215 if (end == nullptr) {
216 return nullptr;
217 }
218 // Skip over '['s
219 if (*start == JVM_SIGNATURE_ARRAY) {
220 do {
221 start++;
222 } while (start < end && *start == JVM_SIGNATURE_ARRAY);
223
224 // Fully qualified class names should not contain a 'L'.
225 // Set bad_class_name to true to indicate that the package name
226 // could not be obtained due to an error condition.
227 // In this situation, is_same_class_package returns false.
228 if (*start == JVM_SIGNATURE_CLASS) {
229 if (bad_class_name != nullptr) {
230 *bad_class_name = true;
231 }
232 return nullptr;
233 }
234 }
235 // A class name could have just the slash character in the name,
236 // in which case start > end
237 if (start >= end) {
238 // No package name
239 if (bad_class_name != nullptr) {
240 *bad_class_name = true;
241 }
242 return nullptr;
243 }
244 return SymbolTable::new_symbol(name, pointer_delta_as_int(start, base), pointer_delta_as_int(end, base));
245 }
246
247 // Given a fully qualified package name, find its defining package in the class loader's
248 // package entry table.
249 PackageEntry* ClassLoader::get_package_entry(Symbol* pkg_name, ClassLoaderData* loader_data) {
250 if (pkg_name == nullptr) {
251 return nullptr;
252 }
253 PackageEntryTable* pkgEntryTable = loader_data->packages();
254 return pkgEntryTable->lookup_only(pkg_name);
255 }
256
257 const char* ClassPathEntry::copy_path(const char* path) {
258 char* copy = NEW_C_HEAP_ARRAY(char, strlen(path)+1, mtClass);
259 strcpy(copy, path);
260 return copy;
261 }
262
263 ClassPathDirEntry::~ClassPathDirEntry() {
264 FREE_C_HEAP_ARRAY(char, _dir);
265 }
266
267 ClassFileStream* ClassPathDirEntry::open_stream(JavaThread* current, const char* name) {
268 // construct full path name
269 assert((_dir != nullptr) && (name != nullptr), "sanity");
270 size_t path_len = strlen(_dir) + strlen(name) + strlen(os::file_separator()) + 1;
271 char* path = NEW_RESOURCE_ARRAY_IN_THREAD(current, char, path_len);
272 int len = jio_snprintf(path, path_len, "%s%s%s", _dir, os::file_separator(), name);
273 assert(len == (int)(path_len - 1), "sanity");
274 // check if file exists
275 struct stat st;
276 if (os::stat(path, &st) == 0) {
277 // found file, open it
278 int file_handle = os::open(path, 0, 0);
279 if (file_handle != -1) {
280 // read contents into resource array
281 u1* buffer = NEW_RESOURCE_ARRAY_IN_THREAD(current, u1, st.st_size);
282 size_t num_read = ::read(file_handle, (char*) buffer, st.st_size);
283 // close file
284 ::close(file_handle);
285 // construct ClassFileStream
286 if (num_read == (size_t)st.st_size) {
287 if (UsePerfData) {
288 ClassLoader::perf_sys_classfile_bytes_read()->inc(num_read);
289 }
290 #ifdef ASSERT
291 // Freeing path is a no-op here as buffer prevents it from being reclaimed. But we keep it for
292 // debug builds so that we guard against use-after-free bugs.
293 FREE_RESOURCE_ARRAY_IN_THREAD(current, char, path, path_len);
294 #endif
295 // We don't verify the length of the classfile stream fits in an int, but this is the
296 // bootloader so we have control of this.
297 // Resource allocated
298 return new ClassFileStream(buffer,
299 checked_cast<int>(st.st_size),
300 _dir,
301 ClassFileStream::verify);
302 }
303 }
304 }
305 FREE_RESOURCE_ARRAY_IN_THREAD(current, char, path, path_len);
306 return nullptr;
307 }
308
309 ClassPathZipEntry::ClassPathZipEntry(jzfile* zip, const char* zip_name,
310 bool is_boot_append, bool from_class_path_attr) : ClassPathEntry() {
311 _zip = zip;
312 _zip_name = copy_path(zip_name);
313 _from_class_path_attr = from_class_path_attr;
314 }
315
316 ClassPathZipEntry::~ClassPathZipEntry() {
317 ZipLibrary::close(_zip);
318 FREE_C_HEAP_ARRAY(char, _zip_name);
319 }
320
321 u1* ClassPathZipEntry::open_entry(JavaThread* current, const char* name, jint* filesize, bool nul_terminate) {
322 // enable call to C land
323 ThreadToNativeFromVM ttn(current);
324 // check whether zip archive contains name
325 jint name_len;
326 jzentry* entry = ZipLibrary::find_entry(_zip, name, filesize, &name_len);
327 if (entry == nullptr) return nullptr;
328 u1* buffer;
329 char name_buf[128];
330 char* filename;
331 if (name_len < 128) {
332 filename = name_buf;
333 } else {
334 filename = NEW_RESOURCE_ARRAY(char, name_len + 1);
335 }
336
337 // read contents into resource array
338 size_t size = (uint32_t)(*filesize);
339 if (nul_terminate) {
340 if (sizeof(size) == sizeof(uint32_t) && size == UINT_MAX) {
341 return nullptr; // 32-bit integer overflow will occur.
342 }
343 size++;
344 }
345 buffer = NEW_RESOURCE_ARRAY(u1, size);
346 if (!ZipLibrary::read_entry(_zip, entry, buffer, filename)) {
347 return nullptr;
348 }
349
350 // return result
351 if (nul_terminate) {
352 buffer[size - 1] = 0;
353 }
354 return buffer;
355 }
356
357 ClassFileStream* ClassPathZipEntry::open_stream(JavaThread* current, const char* name) {
358 jint filesize;
359 u1* buffer = open_entry(current, name, &filesize, false);
360 if (buffer == nullptr) {
361 return nullptr;
362 }
363 if (UsePerfData) {
364 ClassLoader::perf_sys_classfile_bytes_read()->inc(filesize);
365 }
366 // Resource allocated
367 return new ClassFileStream(buffer,
368 filesize,
369 _zip_name,
370 ClassFileStream::verify);
371 }
372
373 DEBUG_ONLY(ClassPathImageEntry* ClassPathImageEntry::_singleton = nullptr;)
374
375 JImageFile* ClassPathImageEntry::jimage() const {
376 return JImage_file;
377 }
378
379 JImageFile* ClassPathImageEntry::jimage_non_null() const {
380 assert(ClassLoader::has_jrt_entry(), "must be");
381 assert(jimage() != nullptr, "should have been opened by ClassLoader::lookup_vm_options "
382 "and remained throughout normal JVM lifetime");
383 return jimage();
384 }
385
386 void ClassPathImageEntry::close_jimage() {
387 if (jimage() != nullptr) {
388 (*JImageClose)(jimage());
389 JImage_file = nullptr;
390 }
391 }
392
393 ClassPathImageEntry::ClassPathImageEntry(JImageFile* jimage, const char* name) :
394 ClassPathEntry() {
395 guarantee(jimage != nullptr, "jimage file is null");
396 guarantee(name != nullptr, "jimage file name is null");
397 assert(_singleton == nullptr, "VM supports only one jimage");
398 DEBUG_ONLY(_singleton = this);
399 size_t len = strlen(name) + 1;
400 _name = copy_path(name);
401 }
402
403 ClassFileStream* ClassPathImageEntry::open_stream(JavaThread* current, const char* name) {
404 return open_stream_for_loader(current, name, ClassLoaderData::the_null_class_loader_data());
405 }
406
407 // For a class in a named module, look it up in the jimage file using this syntax:
408 // /<module-name>/<package-name>/<base-class>
409 //
410 // Assumptions:
411 // 1. There are no unnamed modules in the jimage file.
412 // 2. A package is in at most one module in the jimage file.
413 //
414 ClassFileStream* ClassPathImageEntry::open_stream_for_loader(JavaThread* current, const char* name, ClassLoaderData* loader_data) {
415 jlong size;
416 JImageLocationRef location = (*JImageFindResource)(jimage_non_null(), "", get_jimage_version_string(), name, &size);
417
418 if (location == 0) {
419 TempNewSymbol class_name = SymbolTable::new_symbol(name);
420 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
421
422 if (pkg_name != nullptr) {
423 if (!Universe::is_module_initialized()) {
424 location = (*JImageFindResource)(jimage_non_null(), JAVA_BASE_NAME, get_jimage_version_string(), name, &size);
425 } else {
426 PackageEntry* package_entry = ClassLoader::get_package_entry(pkg_name, loader_data);
427 if (package_entry != nullptr) {
428 ResourceMark rm(current);
429 // Get the module name
430 ModuleEntry* module = package_entry->module();
431 assert(module != nullptr, "Boot classLoader package missing module");
432 assert(module->is_named(), "Boot classLoader package is in unnamed module");
433 const char* module_name = module->name()->as_C_string();
434 if (module_name != nullptr) {
435 location = (*JImageFindResource)(jimage_non_null(), module_name, get_jimage_version_string(), name, &size);
436 }
437 }
438 }
439 }
440 }
441 if (location != 0) {
442 if (UsePerfData) {
443 ClassLoader::perf_sys_classfile_bytes_read()->inc(size);
444 }
445 char* data = NEW_RESOURCE_ARRAY(char, size);
446 (*JImageGetResource)(jimage_non_null(), location, data, size);
447 // Resource allocated
448 assert(this == (ClassPathImageEntry*)ClassLoader::get_jrt_entry(), "must be");
449 return new ClassFileStream((u1*)data,
450 checked_cast<int>(size),
451 _name,
452 ClassFileStream::verify,
453 true); // from_boot_loader_modules_image
454 }
455
456 return nullptr;
457 }
458
459 JImageLocationRef ClassLoader::jimage_find_resource(JImageFile* jf,
460 const char* module_name,
461 const char* file_name,
462 jlong &size) {
463 return ((*JImageFindResource)(jf, module_name, get_jimage_version_string(), file_name, &size));
464 }
465
466 bool ClassPathImageEntry::is_modules_image() const {
467 assert(this == _singleton, "VM supports a single jimage");
468 assert(this == (ClassPathImageEntry*)ClassLoader::get_jrt_entry(), "must be used for jrt entry");
469 return true;
470 }
471
472 #if INCLUDE_CDS
473 void ClassLoader::exit_with_path_failure(const char* error, const char* message) {
474 assert(CDSConfig::is_dumping_archive(), "sanity");
475 tty->print_cr("Hint: enable -Xlog:class+path=info to diagnose the failure");
476 vm_exit_during_cds_dumping(error, message);
477 }
478 #endif
479
480 ModuleClassPathList::ModuleClassPathList(Symbol* module_name) {
481 _module_name = module_name;
482 _module_first_entry = nullptr;
483 _module_last_entry = nullptr;
484 }
485
486 ModuleClassPathList::~ModuleClassPathList() {
487 // Clean out each ClassPathEntry on list
488 ClassPathEntry* e = _module_first_entry;
489 while (e != nullptr) {
490 ClassPathEntry* next_entry = e->next();
491 delete e;
492 e = next_entry;
493 }
494 }
495
496 void ModuleClassPathList::add_to_list(ClassPathEntry* new_entry) {
497 if (new_entry != nullptr) {
498 if (_module_last_entry == nullptr) {
499 _module_first_entry = _module_last_entry = new_entry;
500 } else {
501 _module_last_entry->set_next(new_entry);
502 _module_last_entry = new_entry;
503 }
504 }
505 }
506
507 void ClassLoader::trace_class_path(const char* msg, const char* name) {
508 LogTarget(Info, class, path) lt;
509 if (lt.is_enabled()) {
510 LogStream ls(lt);
511 if (msg) {
512 ls.print("%s", msg);
513 }
514 if (name) {
515 if (strlen(name) < 256) {
516 ls.print("%s", name);
517 } else {
518 // For very long paths, we need to print each character separately,
519 // as print_cr() has a length limit
520 while (name[0] != '\0') {
521 ls.print("%c", name[0]);
522 name++;
523 }
524 }
525 }
526 ls.cr();
527 }
528 }
529
530 void ClassLoader::setup_bootstrap_search_path(JavaThread* current) {
531 const char* bootcp = Arguments::get_boot_class_path();
532 assert(bootcp != nullptr, "Boot class path must not be nullptr");
533 if (PrintSharedArchiveAndExit) {
534 // Don't print bootcp - this is the bootcp of this current VM process, not necessarily
535 // the same as the boot classpath of the shared archive.
536 } else {
537 trace_class_path("bootstrap loader class path=", bootcp);
538 }
539 setup_bootstrap_search_path_impl(current, bootcp);
540 }
541
542 #if INCLUDE_CDS
543 void ClassLoader::setup_app_search_path(JavaThread* current, const char *class_path) {
544 assert(CDSConfig::is_dumping_archive(), "sanity");
545
546 ResourceMark rm(current);
547 ClasspathStream cp_stream(class_path);
548
549 while (cp_stream.has_next()) {
550 const char* path = cp_stream.get_next();
551 update_class_path_entry_list(current, path, /* check_for_duplicates */ true,
552 /* is_boot_append */ false, /* from_class_path_attr */ false);
553 }
554 }
555
556 void ClassLoader::add_to_module_path_entries(const char* path,
557 ClassPathEntry* entry) {
558 assert(entry != nullptr, "ClassPathEntry should not be nullptr");
559 assert(CDSConfig::is_dumping_archive(), "sanity");
560
561 // The entry does not exist, add to the list
562 if (_module_path_entries == nullptr) {
563 assert(_last_module_path_entry == nullptr, "Sanity");
564 _module_path_entries = _last_module_path_entry = entry;
565 } else {
566 _last_module_path_entry->set_next(entry);
567 _last_module_path_entry = entry;
568 }
569 }
570
571 // Add a module path to the _module_path_entries list.
572 void ClassLoader::setup_module_search_path(JavaThread* current, const char* path) {
573 assert(CDSConfig::is_dumping_archive(), "sanity");
574 struct stat st;
575 if (os::stat(path, &st) != 0) {
576 tty->print_cr("os::stat error %d (%s). CDS dump aborted (path was \"%s\").",
577 errno, os::errno_name(errno), path);
578 vm_exit_during_initialization();
579 }
580 // File or directory found
581 ClassPathEntry* new_entry = nullptr;
582 new_entry = create_class_path_entry(current, path, &st,
583 false /*is_boot_append */, false /* from_class_path_attr */);
584 if (new_entry != nullptr) {
585 // ClassLoaderExt::process_module_table() filters out non-jar entries before calling this function.
586 assert(new_entry->is_jar_file(), "module path entry %s is not a jar file", new_entry->name());
587 add_to_module_path_entries(path, new_entry);
588 }
589 }
590
591 #endif // INCLUDE_CDS
592
593 void ClassLoader::close_jrt_image() {
594 // Not applicable for exploded builds
595 if (!ClassLoader::has_jrt_entry()) return;
596 _jrt_entry->close_jimage();
597 }
598
599 // Construct the array of module/path pairs as specified to --patch-module
600 // for the boot loader to search ahead of the jimage, if the class being
601 // loaded is defined to a module that has been specified to --patch-module.
602 void ClassLoader::setup_patch_mod_entries() {
603 JavaThread* current = JavaThread::current();
604 GrowableArray<ModulePatchPath*>* patch_mod_args = Arguments::get_patch_mod_prefix();
605 int num_of_entries = patch_mod_args->length();
606
607 // Set up the boot loader's _patch_mod_entries list
608 _patch_mod_entries = new (mtModule) GrowableArray<ModuleClassPathList*>(num_of_entries, mtModule);
609
610 for (int i = 0; i < num_of_entries; i++) {
611 const char* module_name = (patch_mod_args->at(i))->module_name();
612 Symbol* const module_sym = SymbolTable::new_symbol(module_name);
613 assert(module_sym != nullptr, "Failed to obtain Symbol for module name");
614 ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
615
616 char* class_path = (patch_mod_args->at(i))->path_string();
617 ResourceMark rm(current);
618 ClasspathStream cp_stream(class_path);
619
620 while (cp_stream.has_next()) {
621 const char* path = cp_stream.get_next();
622 struct stat st;
623 if (os::stat(path, &st) == 0) {
624 // File or directory found
625 ClassPathEntry* new_entry = create_class_path_entry(current, path, &st, false, false);
626 // If the path specification is valid, enter it into this module's list
627 if (new_entry != nullptr) {
628 module_cpl->add_to_list(new_entry);
629 }
630 }
631 }
632
633 // Record the module into the list of --patch-module entries only if
634 // valid ClassPathEntrys have been created
635 if (module_cpl->module_first_entry() != nullptr) {
636 _patch_mod_entries->push(module_cpl);
637 }
638 }
639 }
640
641 // Determine whether the module has been patched via the command-line
642 // option --patch-module
643 bool ClassLoader::is_in_patch_mod_entries(Symbol* module_name) {
644 if (_patch_mod_entries != nullptr && _patch_mod_entries->is_nonempty()) {
645 int table_len = _patch_mod_entries->length();
646 for (int i = 0; i < table_len; i++) {
647 ModuleClassPathList* patch_mod = _patch_mod_entries->at(i);
648 if (module_name->fast_compare(patch_mod->module_name()) == 0) {
649 return true;
650 }
651 }
652 }
653 return false;
654 }
655
656 // Set up the _jrt_entry if present and boot append path
657 void ClassLoader::setup_bootstrap_search_path_impl(JavaThread* current, const char *class_path) {
658 ResourceMark rm(current);
659 ClasspathStream cp_stream(class_path);
660 bool set_base_piece = true;
661
662 #if INCLUDE_CDS
663 if (CDSConfig::is_dumping_archive()) {
664 if (!Arguments::has_jimage()) {
665 vm_exit_during_initialization("CDS is not supported in exploded JDK build", nullptr);
666 }
667 }
668 #endif
669
670 while (cp_stream.has_next()) {
671 const char* path = cp_stream.get_next();
672
673 if (set_base_piece) {
674 // The first time through the bootstrap_search setup, it must be determined
675 // what the base or core piece of the boot loader search is. Either a java runtime
676 // image is present or this is an exploded module build situation.
677 assert(string_ends_with(path, MODULES_IMAGE_NAME) || string_ends_with(path, JAVA_BASE_NAME),
678 "Incorrect boot loader search path, no java runtime image or " JAVA_BASE_NAME " exploded build");
679 struct stat st;
680 if (os::stat(path, &st) == 0) {
681 // Directory found
682 if (JImage_file != nullptr) {
683 assert(Arguments::has_jimage(), "sanity check");
684 const char* canonical_path = get_canonical_path(path, current);
685 assert(canonical_path != nullptr, "canonical_path issue");
686
687 _jrt_entry = new ClassPathImageEntry(JImage_file, canonical_path);
688 assert(_jrt_entry != nullptr && _jrt_entry->is_modules_image(), "No java runtime image present");
689 assert(_jrt_entry->jimage() != nullptr, "No java runtime image");
690 } // else it's an exploded build.
691 } else {
692 // If path does not exist, exit
693 vm_exit_during_initialization("Unable to establish the boot loader search path", path);
694 }
695 set_base_piece = false;
696 } else {
697 // Every entry on the boot class path after the initial base piece,
698 // which is set by os::set_boot_path(), is considered an appended entry.
699 update_class_path_entry_list(current, path, /* check_for_duplicates */ false,
700 /* is_boot_append */ true, /* from_class_path_attr */ false);
701 }
702 }
703 }
704
705 // Gets the exploded path for the named module. The memory for the path
706 // is allocated on the C heap if `c_heap` is true otherwise in the resource area.
707 static const char* get_exploded_module_path(const char* module_name, bool c_heap) {
708 const char *home = Arguments::get_java_home();
709 const char file_sep = os::file_separator()[0];
710 // 10 represents the length of "modules" + 2 file separators + \0
711 size_t len = strlen(home) + strlen(module_name) + 10;
712 char *path = c_heap ? NEW_C_HEAP_ARRAY(char, len, mtModule) : NEW_RESOURCE_ARRAY(char, len);
713 jio_snprintf(path, len, "%s%cmodules%c%s", home, file_sep, file_sep, module_name);
714 return path;
715 }
716
717 // During an exploded modules build, each module defined to the boot loader
718 // will be added to the ClassLoader::_exploded_entries array.
719 void ClassLoader::add_to_exploded_build_list(JavaThread* current, Symbol* module_sym) {
720 assert(!ClassLoader::has_jrt_entry(), "Exploded build not applicable");
721 assert(_exploded_entries != nullptr, "_exploded_entries was not initialized");
722
723 // Find the module's symbol
724 ResourceMark rm(current);
725 const char *module_name = module_sym->as_C_string();
726 const char *path = get_exploded_module_path(module_name, false);
727
728 struct stat st;
729 if (os::stat(path, &st) == 0) {
730 // Directory found
731 ClassPathEntry* new_entry = create_class_path_entry(current, path, &st, false, false);
732
733 // If the path specification is valid, enter it into this module's list.
734 // There is no need to check for duplicate modules in the exploded entry list,
735 // since no two modules with the same name can be defined to the boot loader.
736 // This is checked at module definition time in Modules::define_module.
737 if (new_entry != nullptr) {
738 ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
739 module_cpl->add_to_list(new_entry);
740 {
741 MutexLocker ml(current, Module_lock);
742 _exploded_entries->push(module_cpl);
743 }
744 log_info(class, load)("path: %s", path);
745 }
746 }
747 }
748
749 jzfile* ClassLoader::open_zip_file(const char* canonical_path, char** error_msg, JavaThread* thread) {
750 // enable call to C land
751 ThreadToNativeFromVM ttn(thread);
752 HandleMark hm(thread);
753 return ZipLibrary::open(canonical_path, error_msg);
754 }
755
756 ClassPathEntry* ClassLoader::create_class_path_entry(JavaThread* current,
757 const char *path, const struct stat* st,
758 bool is_boot_append,
759 bool from_class_path_attr) {
760 ClassPathEntry* new_entry = nullptr;
761 if ((st->st_mode & S_IFMT) == S_IFREG) {
762 ResourceMark rm(current);
763 // Regular file, should be a zip file
764 // Canonicalized filename
765 const char* canonical_path = get_canonical_path(path, current);
766 if (canonical_path == nullptr) {
767 return nullptr;
768 }
769 char* error_msg = nullptr;
770 jzfile* zip = open_zip_file(canonical_path, &error_msg, current);
771 if (zip != nullptr && error_msg == nullptr) {
772 new_entry = new ClassPathZipEntry(zip, path, is_boot_append, from_class_path_attr);
773 } else {
774 #if INCLUDE_CDS
775 ClassLoaderExt::set_has_non_jar_in_classpath();
776 #endif
777 return nullptr;
778 }
779 log_info(class, path)("opened: %s", path);
780 log_info(class, load)("opened: %s", path);
781 } else {
782 // Directory
783 new_entry = new ClassPathDirEntry(path);
784 log_info(class, load)("path: %s", path);
785 }
786 return new_entry;
787 }
788
789
790 // Create a class path zip entry for a given path (return null if not found
791 // or zip/JAR file cannot be opened)
792 ClassPathZipEntry* ClassLoader::create_class_path_zip_entry(const char *path, bool is_boot_append) {
793 // check for a regular file
794 struct stat st;
795 if (os::stat(path, &st) == 0) {
796 if ((st.st_mode & S_IFMT) == S_IFREG) {
797 JavaThread* thread = JavaThread::current();
798 ResourceMark rm(thread);
799 const char* canonical_path = get_canonical_path(path, thread);
800 if (canonical_path != nullptr) {
801 char* error_msg = nullptr;
802 jzfile* zip = open_zip_file(canonical_path, &error_msg, thread);
803 if (zip != nullptr && error_msg == nullptr) {
804 // create using canonical path
805 return new ClassPathZipEntry(zip, canonical_path, is_boot_append, false);
806 }
807 }
808 }
809 }
810 return nullptr;
811 }
812
813 // The boot append entries are added with a lock, and read lock free.
814 void ClassLoader::add_to_boot_append_entries(ClassPathEntry *new_entry) {
815 if (new_entry != nullptr) {
816 MutexLocker ml(Bootclasspath_lock, Mutex::_no_safepoint_check_flag);
817 if (_last_append_entry == nullptr) {
818 _last_append_entry = new_entry;
819 assert(first_append_entry() == nullptr, "boot loader's append class path entry list not empty");
820 Atomic::release_store(&_first_append_entry_list, new_entry);
821 } else {
822 _last_append_entry->set_next(new_entry);
823 _last_append_entry = new_entry;
824 }
825 }
826 }
827
828 // Record the path entries specified in -cp during dump time. The recorded
829 // information will be used at runtime for loading the archived app classes.
830 //
831 // Note that at dump time, ClassLoader::_app_classpath_entries are NOT used for
832 // loading app classes. Instead, the app class are loaded by the
833 // jdk/internal/loader/ClassLoaders$AppClassLoader instance.
834 bool ClassLoader::add_to_app_classpath_entries(JavaThread* current,
835 ClassPathEntry* entry,
836 bool check_for_duplicates) {
837 #if INCLUDE_CDS
838 assert(entry != nullptr, "ClassPathEntry should not be nullptr");
839 ClassPathEntry* e = _app_classpath_entries;
840 if (check_for_duplicates) {
841 while (e != nullptr) {
842 if (strcmp(e->name(), entry->name()) == 0 &&
843 e->from_class_path_attr() == entry->from_class_path_attr()) {
844 // entry already exists
845 return false;
846 }
847 e = e->next();
848 }
849 }
850
851 // The entry does not exist, add to the list
852 if (_app_classpath_entries == nullptr) {
853 assert(_last_app_classpath_entry == nullptr, "Sanity");
854 _app_classpath_entries = _last_app_classpath_entry = entry;
855 } else {
856 _last_app_classpath_entry->set_next(entry);
857 _last_app_classpath_entry = entry;
858 }
859
860 if (entry->is_jar_file()) {
861 ClassLoaderExt::process_jar_manifest(current, entry);
862 }
863 #endif
864 return true;
865 }
866
867 // Returns true IFF the file/dir exists and the entry was successfully created.
868 bool ClassLoader::update_class_path_entry_list(JavaThread* current,
869 const char *path,
870 bool check_for_duplicates,
871 bool is_boot_append,
872 bool from_class_path_attr) {
873 struct stat st;
874 if (os::stat(path, &st) == 0) {
875 // File or directory found
876 ClassPathEntry* new_entry = nullptr;
877 new_entry = create_class_path_entry(current, path, &st, is_boot_append, from_class_path_attr);
878 if (new_entry == nullptr) {
879 return false;
880 }
881
882 // Do not reorder the bootclasspath which would break get_system_package().
883 // Add new entry to linked list
884 if (is_boot_append) {
885 add_to_boot_append_entries(new_entry);
886 } else {
887 if (!add_to_app_classpath_entries(current, new_entry, check_for_duplicates)) {
888 // new_entry is not saved, free it now
889 delete new_entry;
890 }
891 }
892 return true;
893 } else {
894 return false;
895 }
896 }
897
898 static void print_module_entry_table(const GrowableArray<ModuleClassPathList*>* const module_list) {
899 ResourceMark rm;
900 int num_of_entries = module_list->length();
901 for (int i = 0; i < num_of_entries; i++) {
902 ClassPathEntry* e;
903 ModuleClassPathList* mpl = module_list->at(i);
904 tty->print("%s=", mpl->module_name()->as_C_string());
905 e = mpl->module_first_entry();
906 while (e != nullptr) {
907 tty->print("%s", e->name());
908 e = e->next();
909 if (e != nullptr) {
910 tty->print("%s", os::path_separator());
911 }
912 }
913 tty->print(" ;");
914 }
915 }
916
917 void ClassLoader::print_bootclasspath() {
918 ClassPathEntry* e;
919 tty->print("[bootclasspath= ");
920
921 // Print --patch-module module/path specifications first
922 if (_patch_mod_entries != nullptr) {
923 print_module_entry_table(_patch_mod_entries);
924 }
925
926 // [jimage | exploded modules build]
927 if (has_jrt_entry()) {
928 // Print the location of the java runtime image
929 tty->print("%s ;", _jrt_entry->name());
930 } else {
931 // Print exploded module build path specifications
932 if (_exploded_entries != nullptr) {
933 print_module_entry_table(_exploded_entries);
934 }
935 }
936
937 // appended entries
938 e = first_append_entry();
939 while (e != nullptr) {
940 tty->print("%s ;", e->name());
941 e = e->next();
942 }
943 tty->print_cr("]");
944 }
945
946 void* ClassLoader::dll_lookup(void* lib, const char* name, const char* path) {
947 void* func = os::dll_lookup(lib, name);
948 if (func == nullptr) {
949 char msg[256] = "";
950 jio_snprintf(msg, sizeof(msg), "Could not resolve \"%s\"", name);
951 vm_exit_during_initialization(msg, path);
952 }
953 return func;
954 }
955
956 void ClassLoader::load_java_library() {
957 assert(CanonicalizeEntry == nullptr, "should not load java library twice");
958 void *javalib_handle = os::native_java_library();
959 if (javalib_handle == nullptr) {
960 vm_exit_during_initialization("Unable to load java library", nullptr);
961 }
962
963 CanonicalizeEntry = CAST_TO_FN_PTR(canonicalize_fn_t, dll_lookup(javalib_handle, "JDK_Canonicalize", nullptr));
964 }
965
966 void ClassLoader::load_jimage_library() {
967 assert(JImageOpen == nullptr, "should not load jimage library twice");
968 char path[JVM_MAXPATHLEN];
969 char ebuf[1024];
970 void* handle = nullptr;
971 if (os::dll_locate_lib(path, sizeof(path), Arguments::get_dll_dir(), "jimage")) {
972 handle = os::dll_load(path, ebuf, sizeof ebuf);
973 }
974 if (handle == nullptr) {
975 vm_exit_during_initialization("Unable to load jimage library", path);
976 }
977
978 JImageOpen = CAST_TO_FN_PTR(JImageOpen_t, dll_lookup(handle, "JIMAGE_Open", path));
979 JImageClose = CAST_TO_FN_PTR(JImageClose_t, dll_lookup(handle, "JIMAGE_Close", path));
980 JImageFindResource = CAST_TO_FN_PTR(JImageFindResource_t, dll_lookup(handle, "JIMAGE_FindResource", path));
981 JImageGetResource = CAST_TO_FN_PTR(JImageGetResource_t, dll_lookup(handle, "JIMAGE_GetResource", path));
982 }
983
984 int ClassLoader::crc32(int crc, const char* buf, int len) {
985 return ZipLibrary::crc32(crc, (const jbyte*)buf, len);
986 }
987
988 oop ClassLoader::get_system_package(const char* name, TRAPS) {
989 // Look up the name in the boot loader's package entry table.
990 if (name != nullptr) {
991 TempNewSymbol package_sym = SymbolTable::new_symbol(name);
992 // Look for the package entry in the boot loader's package entry table.
993 PackageEntry* package =
994 ClassLoaderData::the_null_class_loader_data()->packages()->lookup_only(package_sym);
995
996 // Return null if package does not exist or if no classes in that package
997 // have been loaded.
998 if (package != nullptr && package->has_loaded_class()) {
999 ModuleEntry* module = package->module();
1000 if (module->location() != nullptr) {
1001 ResourceMark rm(THREAD);
1002 Handle ml = java_lang_String::create_from_str(
1003 module->location()->as_C_string(), THREAD);
1004 return ml();
1005 }
1006 // Return entry on boot loader class path.
1007 Handle cph = java_lang_String::create_from_str(
1008 ClassLoader::classpath_entry(package->classpath_index())->name(), THREAD);
1009 return cph();
1010 }
1011 }
1012 return nullptr;
1013 }
1014
1015 objArrayOop ClassLoader::get_system_packages(TRAPS) {
1016 ResourceMark rm(THREAD);
1017 // List of pointers to PackageEntrys that have loaded classes.
1018 PackageEntryTable* pe_table =
1019 ClassLoaderData::the_null_class_loader_data()->packages();
1020 GrowableArray<PackageEntry*>* loaded_class_pkgs = pe_table->get_system_packages();
1021
1022 // Allocate objArray and fill with java.lang.String
1023 objArrayOop r = oopFactory::new_objArray(vmClasses::String_klass(),
1024 loaded_class_pkgs->length(), CHECK_NULL);
1025 objArrayHandle result(THREAD, r);
1026 for (int x = 0; x < loaded_class_pkgs->length(); x++) {
1027 PackageEntry* package_entry = loaded_class_pkgs->at(x);
1028 Handle str = java_lang_String::create_from_symbol(package_entry->name(), CHECK_NULL);
1029 result->obj_at_put(x, str());
1030 }
1031 return result();
1032 }
1033
1034 // caller needs ResourceMark
1035 const char* ClassLoader::file_name_for_class_name(const char* class_name,
1036 int class_name_len) {
1037 assert(class_name != nullptr, "invariant");
1038 assert((int)strlen(class_name) == class_name_len, "invariant");
1039
1040 static const char class_suffix[] = ".class";
1041 size_t class_suffix_len = sizeof(class_suffix);
1042
1043 char* const file_name = NEW_RESOURCE_ARRAY(char,
1044 class_name_len +
1045 class_suffix_len); // includes term null
1046
1047 strncpy(file_name, class_name, class_name_len);
1048 strncpy(&file_name[class_name_len], class_suffix, class_suffix_len);
1049
1050 return file_name;
1051 }
1052
1053 static ClassPathEntry* find_first_module_cpe(ModuleEntry* mod_entry,
1054 const GrowableArray<ModuleClassPathList*>* const module_list) {
1055 int num_of_entries = module_list->length();
1056 const Symbol* class_module_name = mod_entry->name();
1057
1058 // Loop through all the modules in either the patch-module or exploded entries looking for module
1059 for (int i = 0; i < num_of_entries; i++) {
1060 ModuleClassPathList* module_cpl = module_list->at(i);
1061 Symbol* module_cpl_name = module_cpl->module_name();
1062
1063 if (module_cpl_name->fast_compare(class_module_name) == 0) {
1064 // Class' module has been located.
1065 return module_cpl->module_first_entry();
1066 }
1067 }
1068 return nullptr;
1069 }
1070
1071
1072 // Search the module list for the class file stream based on the file name and java package
1073 ClassFileStream* ClassLoader::search_module_entries(JavaThread* current,
1074 const GrowableArray<ModuleClassPathList*>* const module_list,
1075 PackageEntry* pkg_entry, // Java package entry derived from the class name
1076 const char* const file_name) {
1077 ClassFileStream* stream = nullptr;
1078
1079 // Find the defining module in the boot loader's module entry table
1080 ModuleEntry* mod_entry = (pkg_entry != nullptr) ? pkg_entry->module() : nullptr;
1081
1082 // If the module system has not defined java.base yet, then
1083 // classes loaded are assumed to be defined to java.base.
1084 // When java.base is eventually defined by the module system,
1085 // all packages of classes that have been previously loaded
1086 // are verified in ModuleEntryTable::verify_javabase_packages().
1087 if (!Universe::is_module_initialized() &&
1088 !ModuleEntryTable::javabase_defined() &&
1089 mod_entry == nullptr) {
1090 mod_entry = ModuleEntryTable::javabase_moduleEntry();
1091 }
1092
1093 // The module must be a named module
1094 ClassPathEntry* e = nullptr;
1095 if (mod_entry != nullptr && mod_entry->is_named()) {
1096 if (module_list == _exploded_entries) {
1097 // The exploded build entries can be added to at any time so a lock is
1098 // needed when searching them.
1099 assert(!ClassLoader::has_jrt_entry(), "Must be exploded build");
1100 MutexLocker ml(current, Module_lock);
1101 e = find_first_module_cpe(mod_entry, module_list);
1102 } else {
1103 e = find_first_module_cpe(mod_entry, module_list);
1104 }
1105 }
1106
1107 // Try to load the class from the module's ClassPathEntry list.
1108 while (e != nullptr) {
1109 stream = e->open_stream(current, file_name);
1110 // No context.check is required since CDS is not supported
1111 // for an exploded modules build or if --patch-module is specified.
1112 if (nullptr != stream) {
1113 return stream;
1114 }
1115 e = e->next();
1116 }
1117 // If the module was located, break out even if the class was not
1118 // located successfully from that module's ClassPathEntry list.
1119 // There will not be another valid entry for that module.
1120 return nullptr;
1121 }
1122
1123 // Called by the boot classloader to load classes
1124 InstanceKlass* ClassLoader::load_class(Symbol* name, PackageEntry* pkg_entry, bool search_append_only, TRAPS) {
1125 assert(name != nullptr, "invariant");
1126
1127 ResourceMark rm(THREAD);
1128 HandleMark hm(THREAD);
1129
1130 const char* const class_name = name->as_C_string();
1131
1132 EventMarkClassLoading m("Loading class %s", class_name);
1133
1134 const char* const file_name = file_name_for_class_name(class_name,
1135 name->utf8_length());
1136 assert(file_name != nullptr, "invariant");
1137
1138 // Lookup stream for parsing .class file
1139 ClassFileStream* stream = nullptr;
1140 s2 classpath_index = 0;
1141 ClassPathEntry* e = nullptr;
1142 bool is_patched = false;
1143
1144 // If search_append_only is true, boot loader visibility boundaries are
1145 // set to be _first_append_entry to the end. This includes:
1146 // [-Xbootclasspath/a]; [jvmti appended entries]
1147 //
1148 // If search_append_only is false, boot loader visibility boundaries are
1149 // set to be the --patch-module entries plus the base piece. This includes:
1150 // [--patch-module=<module>=<file>(<pathsep><file>)*]; [jimage | exploded module build]
1151 //
1152
1153 // Load Attempt #1: --patch-module
1154 // Determine the class' defining module. If it appears in the _patch_mod_entries,
1155 // attempt to load the class from those locations specific to the module.
1156 // Specifications to --patch-module can contain a partial number of classes
1157 // that are part of the overall module definition. So if a particular class is not
1158 // found within its module specification, the search should continue to Load Attempt #2.
1159 // Note: The --patch-module entries are never searched if the boot loader's
1160 // visibility boundary is limited to only searching the append entries.
1161 if (_patch_mod_entries != nullptr && !search_append_only) {
1162 // At CDS dump time, the --patch-module entries are ignored. That means a
1163 // class is still loaded from the runtime image even if it might
1164 // appear in the _patch_mod_entries. The runtime shared class visibility
1165 // check will determine if a shared class is visible based on the runtime
1166 // environment, including the runtime --patch-module setting.
1167 if (!CDSConfig::is_valhalla_preview()) {
1168 // Dynamic dumping requires UseSharedSpaces to be enabled. Since --patch-module
1169 // is not supported with UseSharedSpaces, we can never come here during dynamic dumping.
1170 assert(!CDSConfig::is_dumping_archive(), "CDS doesn't support --patch-module during dumping");
1171 }
1172 if (CDSConfig::is_valhalla_preview() || !CDSConfig::is_dumping_static_archive()) {
1173 stream = search_module_entries(THREAD, _patch_mod_entries, pkg_entry, file_name);
1174 if (stream != nullptr) {
1175 is_patched = true;
1176 }
1177 }
1178 }
1179
1180 // Load Attempt #2: [jimage | exploded build]
1181 if (!search_append_only && (nullptr == stream)) {
1182 if (has_jrt_entry()) {
1183 e = _jrt_entry;
1184 stream = _jrt_entry->open_stream(THREAD, file_name);
1185 } else {
1186 // Exploded build - attempt to locate class in its defining module's location.
1187 assert(_exploded_entries != nullptr, "No exploded build entries present");
1188 assert(!CDSConfig::is_dumping_archive(), "CDS dumping doesn't support exploded build");
1189 stream = search_module_entries(THREAD, _exploded_entries, pkg_entry, file_name);
1190 }
1191 }
1192
1193 // Load Attempt #3: [-Xbootclasspath/a]; [jvmti appended entries]
1194 if (search_append_only && (nullptr == stream)) {
1195 // For the boot loader append path search, the starting classpath_index
1196 // for the appended piece is always 1 to account for either the
1197 // _jrt_entry or the _exploded_entries.
1198 assert(classpath_index == 0, "The classpath_index has been incremented incorrectly");
1199 classpath_index = 1;
1200
1201 e = first_append_entry();
1202 while (e != nullptr) {
1203 stream = e->open_stream(THREAD, file_name);
1204 if (nullptr != stream) {
1205 break;
1206 }
1207 e = e->next();
1208 ++classpath_index;
1209 }
1210 }
1211
1212 if (nullptr == stream) {
1213 return nullptr;
1214 }
1215
1216 stream->set_verify(ClassLoaderExt::should_verify(classpath_index));
1217
1218 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
1219 Handle protection_domain;
1220 ClassLoadInfo cl_info(protection_domain);
1221
1222 InstanceKlass* result = KlassFactory::create_from_stream(stream,
1223 name,
1224 loader_data,
1225 cl_info,
1226 CHECK_NULL);
1227 result->set_classpath_index(classpath_index);
1228 if (is_patched) {
1229 result->set_shared_classpath_index(0);
1230 result->set_shared_class_loader_type(ClassLoader::BOOT_LOADER);
1231 }
1232 return result;
1233 }
1234
1235 #if INCLUDE_CDS
1236 static const char* skip_uri_protocol(const char* source) {
1237 if (strncmp(source, "file:", 5) == 0) {
1238 // file: protocol path could start with file:/ or file:///
1239 // locate the char after all the forward slashes
1240 int offset = 5;
1241 while (*(source + offset) == '/') {
1242 offset++;
1243 }
1244 source += offset;
1245 // for non-windows platforms, move back one char as the path begins with a '/'
1246 #ifndef _WINDOWS
1247 source -= 1;
1248 #endif
1249 } else if (strncmp(source, "jrt:/", 5) == 0) {
1250 source += 5;
1251 }
1252 return source;
1253 }
1254
1255 static char decode_percent_encoded(const char *str, size_t& index) {
1256 if (str[index] == '%'
1257 && isxdigit(str[index + 1])
1258 && isxdigit(str[index + 2])) {
1259 char hex[3];
1260 hex[0] = str[index + 1];
1261 hex[1] = str[index + 2];
1262 hex[2] = '\0';
1263 index += 2;
1264 return (char) strtol(hex, NULL, 16);
1265 }
1266 return str[index];
1267 }
1268
1269 char* ClassLoader::uri_to_path(const char* uri) {
1270 const size_t len = strlen(uri) + 1;
1271 char* path = NEW_RESOURCE_ARRAY(char, len);
1272
1273 uri = skip_uri_protocol(uri);
1274
1275 if (strncmp(uri, "//", 2) == 0) {
1276 // Skip the empty "authority" part
1277 uri += 2;
1278 }
1279
1280 #ifdef _WINDOWS
1281 if (uri[0] == '/') {
1282 // Absolute path name on Windows does not begin with a slash
1283 uri += 1;
1284 }
1285 #endif
1286
1287 size_t path_index = 0;
1288 for (size_t i = 0; i < strlen(uri); ++i) {
1289 char decoded = decode_percent_encoded(uri, i);
1290 path[path_index++] = decoded;
1291 }
1292 path[path_index] = '\0';
1293 return path;
1294 }
1295
1296 // Record the shared classpath index and loader type for classes loaded
1297 // by the builtin loaders at dump time.
1298 void ClassLoader::record_result(JavaThread* current, InstanceKlass* ik,
1299 const ClassFileStream* stream, bool redefined) {
1300 assert(CDSConfig::is_dumping_archive(), "sanity");
1301 assert(stream != nullptr, "sanity");
1302
1303 if (ik->is_hidden()) {
1304 // We do not archive hidden classes.
1305 return;
1306 }
1307
1308 if (ik->shared_classpath_index() == 0 && ik->is_shared_boot_class()) {
1309 return;
1310 }
1311
1312 oop loader = ik->class_loader();
1313 char* src = (char*)stream->source();
1314 if (src == nullptr) {
1315 if (loader == nullptr) {
1316 // JFR classes
1317 ik->set_shared_classpath_index(0);
1318 ik->set_shared_class_loader_type(ClassLoader::BOOT_LOADER);
1319 }
1320 return;
1321 }
1322
1323 assert(has_jrt_entry(), "CDS dumping does not support exploded JDK build");
1324
1325 ResourceMark rm(current);
1326 int classpath_index = -1;
1327 PackageEntry* pkg_entry = ik->package();
1328
1329 if (FileMapInfo::get_number_of_shared_paths() > 0) {
1330 // Save the path from the file: protocol or the module name from the jrt: protocol
1331 // if no protocol prefix is found, path is the same as stream->source(). This path
1332 // must be valid since the class has been successfully parsed.
1333 const char* path = ClassLoader::uri_to_path(src);
1334 assert(path != nullptr, "sanity");
1335 for (int i = 0; i < FileMapInfo::get_number_of_shared_paths(); i++) {
1336 SharedClassPathEntry* ent = FileMapInfo::shared_path(i);
1337 // A shared path has been validated during its creation in ClassLoader::create_class_path_entry(),
1338 // it must be valid here.
1339 assert(ent->name() != nullptr, "sanity");
1340 // If the path (from the class stream source) is the same as the shared
1341 // class or module path, then we have a match.
1342 // src may come from the App/Platform class loaders, which would canonicalize
1343 // the file name. We cannot use strcmp to check for equality against ent->name().
1344 // We must use os::same_files (which is faster than canonicalizing ent->name()).
1345 if (os::same_files(ent->name(), path)) {
1346 // null pkg_entry and pkg_entry in an unnamed module implies the class
1347 // is from the -cp or boot loader append path which consists of -Xbootclasspath/a
1348 // and jvmti appended entries.
1349 if ((pkg_entry == nullptr) || (pkg_entry->in_unnamed_module())) {
1350 // Ensure the index is within the -cp range before assigning
1351 // to the classpath_index.
1352 if (SystemDictionary::is_system_class_loader(loader) &&
1353 (i >= ClassLoaderExt::app_class_paths_start_index()) &&
1354 (i < ClassLoaderExt::app_module_paths_start_index())) {
1355 classpath_index = i;
1356 break;
1357 } else {
1358 if ((i >= 1) &&
1359 (i < ClassLoaderExt::app_class_paths_start_index())) {
1360 // The class must be from boot loader append path which consists of
1361 // -Xbootclasspath/a and jvmti appended entries.
1362 assert(loader == nullptr, "sanity");
1363 classpath_index = i;
1364 break;
1365 }
1366 }
1367 } else {
1368 // A class from a named module from the --module-path. Ensure the index is
1369 // within the --module-path range before assigning to the classpath_index.
1370 if ((pkg_entry != nullptr) && !(pkg_entry->in_unnamed_module()) && (i > 0)) {
1371 if (i >= ClassLoaderExt::app_module_paths_start_index() &&
1372 i < FileMapInfo::get_number_of_shared_paths()) {
1373 classpath_index = i;
1374 break;
1375 }
1376 }
1377 }
1378 }
1379 // for index 0 and the stream->source() is the modules image or has the jrt: protocol.
1380 // The class must be from the runtime modules image.
1381 if (i == 0 && (stream->from_boot_loader_modules_image() || string_starts_with(src, "jrt:"))) {
1382 classpath_index = i;
1383 break;
1384 }
1385 }
1386
1387 // No path entry found for this class: most likely a shared class loaded by the
1388 // user defined classloader.
1389 if (classpath_index < 0 && !SystemDictionaryShared::is_builtin_loader(ik->class_loader_data())) {
1390 assert(ik->shared_classpath_index() < 0, "not assigned yet");
1391 ik->set_shared_classpath_index(UNREGISTERED_INDEX);
1392 SystemDictionaryShared::set_shared_class_misc_info(ik, (ClassFileStream*)stream);
1393 return;
1394 }
1395 } else {
1396 // The shared path table is set up after module system initialization.
1397 // The path table contains no entry before that. Any classes loaded prior
1398 // to the setup of the shared path table must be from the modules image.
1399 if (!CDSConfig::is_valhalla_preview()) {
1400 assert(stream->from_boot_loader_modules_image(), "stream must be loaded by boot loader from modules image");
1401 }
1402 assert(FileMapInfo::get_number_of_shared_paths() == 0, "shared path table must not have been setup");
1403 classpath_index = 0;
1404 }
1405
1406 const char* const class_name = ik->name()->as_C_string();
1407 const char* const file_name = file_name_for_class_name(class_name,
1408 ik->name()->utf8_length());
1409 assert(file_name != nullptr, "invariant");
1410 ClassLoaderExt::record_result(checked_cast<s2>(classpath_index), ik, redefined);
1411 }
1412 #endif // INCLUDE_CDS
1413
1414 // Initialize the class loader's access to methods in libzip. Parse and
1415 // process the boot classpath into a list ClassPathEntry objects. Once
1416 // this list has been created, it must not change order (see class PackageInfo)
1417 // it can be appended to and is by jvmti.
1418
1419 void ClassLoader::initialize(TRAPS) {
1420 if (UsePerfData) {
1421 // jvmstat performance counters
1422 NEWPERFTICKCOUNTER(_perf_accumulated_time, SUN_CLS, "time");
1423 NEWPERFTICKCOUNTER(_perf_class_init_time, SUN_CLS, "classInitTime");
1424 NEWPERFTICKCOUNTER(_perf_class_init_selftime, SUN_CLS, "classInitTime.self");
1425 NEWPERFTICKCOUNTER(_perf_class_verify_time, SUN_CLS, "classVerifyTime");
1426 NEWPERFTICKCOUNTER(_perf_class_verify_selftime, SUN_CLS, "classVerifyTime.self");
1427 NEWPERFTICKCOUNTER(_perf_class_link_time, SUN_CLS, "classLinkedTime");
1428 NEWPERFTICKCOUNTER(_perf_class_link_selftime, SUN_CLS, "classLinkedTime.self");
1429 NEWPERFEVENTCOUNTER(_perf_classes_inited, SUN_CLS, "initializedClasses");
1430 NEWPERFEVENTCOUNTER(_perf_classes_linked, SUN_CLS, "linkedClasses");
1431 NEWPERFEVENTCOUNTER(_perf_classes_verified, SUN_CLS, "verifiedClasses");
1432
1433 NEWPERFTICKCOUNTER(_perf_shared_classload_time, SUN_CLS, "sharedClassLoadTime");
1434 NEWPERFTICKCOUNTER(_perf_sys_classload_time, SUN_CLS, "sysClassLoadTime");
1435 NEWPERFTICKCOUNTER(_perf_app_classload_time, SUN_CLS, "appClassLoadTime");
1436 NEWPERFTICKCOUNTER(_perf_app_classload_selftime, SUN_CLS, "appClassLoadTime.self");
1437 NEWPERFEVENTCOUNTER(_perf_app_classload_count, SUN_CLS, "appClassLoadCount");
1438 NEWPERFTICKCOUNTER(_perf_define_appclasses, SUN_CLS, "defineAppClasses");
1439 NEWPERFTICKCOUNTER(_perf_define_appclass_time, SUN_CLS, "defineAppClassTime");
1440 NEWPERFTICKCOUNTER(_perf_define_appclass_selftime, SUN_CLS, "defineAppClassTime.self");
1441 NEWPERFBYTECOUNTER(_perf_app_classfile_bytes_read, SUN_CLS, "appClassBytes");
1442 NEWPERFBYTECOUNTER(_perf_sys_classfile_bytes_read, SUN_CLS, "sysClassBytes");
1443 NEWPERFEVENTCOUNTER(_unsafe_defineClassCallCounter, SUN_CLS, "unsafeDefineClassCalls");
1444 NEWPERFTICKCOUNTER(_perf_secondary_hash_time, SUN_CLS, "secondarySuperHashTime");
1445
1446 if (log_is_enabled(Info, perf, class, link)) {
1447 NEWPERFTICKCOUNTER(_perf_ik_link_methods_time, SUN_CLS, "linkMethodsTime");
1448 NEWPERFTICKCOUNTER(_perf_method_adapters_time, SUN_CLS, "makeAdaptersTime");
1449 NEWPERFEVENTCOUNTER(_perf_ik_link_methods_count, SUN_CLS, "linkMethodsCount");
1450 NEWPERFEVENTCOUNTER(_perf_method_adapters_count, SUN_CLS, "makeAdaptersCount");
1451
1452 NEWPERFTICKCOUNTER(_perf_resolve_indy_time, SUN_CLS, "resolve_invokedynamic_time");
1453 NEWPERFTICKCOUNTER(_perf_resolve_invokehandle_time, SUN_CLS, "resolve_invokehandle_time");
1454 NEWPERFTICKCOUNTER(_perf_resolve_mh_time, SUN_CLS, "resolve_MethodHandle_time");
1455 NEWPERFTICKCOUNTER(_perf_resolve_mt_time, SUN_CLS, "resolve_MethodType_time");
1456
1457 NEWPERFEVENTCOUNTER(_perf_resolve_indy_count, SUN_CLS, "resolve_invokedynamic_count");
1458 NEWPERFEVENTCOUNTER(_perf_resolve_invokehandle_count, SUN_CLS, "resolve_invokehandle_count");
1459 NEWPERFEVENTCOUNTER(_perf_resolve_mh_count, SUN_CLS, "resolve_MethodHandle_count");
1460 NEWPERFEVENTCOUNTER(_perf_resolve_mt_count, SUN_CLS, "resolve_MethodType_count");
1461 }
1462 }
1463
1464 // lookup java library entry points
1465 load_java_library();
1466 // jimage library entry points are loaded below, in lookup_vm_options
1467 setup_bootstrap_search_path(THREAD);
1468 }
1469
1470 static char* lookup_vm_resource(JImageFile *jimage, const char *jimage_version, const char *path) {
1471 jlong size;
1472 JImageLocationRef location = (*JImageFindResource)(jimage, "java.base", jimage_version, path, &size);
1473 if (location == 0)
1474 return nullptr;
1475 char *val = NEW_C_HEAP_ARRAY(char, size+1, mtClass);
1476 (*JImageGetResource)(jimage, location, val, size);
1477 val[size] = '\0';
1478 return val;
1479 }
1480
1481 // Lookup VM options embedded in the modules jimage file
1482 char* ClassLoader::lookup_vm_options() {
1483 jint error;
1484 char modules_path[JVM_MAXPATHLEN];
1485 const char* fileSep = os::file_separator();
1486
1487 // Initialize jimage library entry points
1488 load_jimage_library();
1489
1490 jio_snprintf(modules_path, JVM_MAXPATHLEN, "%s%slib%smodules", Arguments::get_java_home(), fileSep, fileSep);
1491 JImage_file =(*JImageOpen)(modules_path, &error);
1492 if (JImage_file == nullptr) {
1493 return nullptr;
1494 }
1495
1496 const char *jimage_version = get_jimage_version_string();
1497 char *options = lookup_vm_resource(JImage_file, jimage_version, "jdk/internal/vm/options");
1498 return options;
1499 }
1500
1501 bool ClassLoader::is_module_observable(const char* module_name) {
1502 assert(JImageOpen != nullptr, "jimage library should have been opened");
1503 if (JImage_file == nullptr) {
1504 struct stat st;
1505 const char *path = get_exploded_module_path(module_name, true);
1506 bool res = os::stat(path, &st) == 0;
1507 FREE_C_HEAP_ARRAY(char, path);
1508 return res;
1509 }
1510 jlong size;
1511 const char *jimage_version = get_jimage_version_string();
1512 return (*JImageFindResource)(JImage_file, module_name, jimage_version, "module-info.class", &size) != 0;
1513 }
1514
1515 #if INCLUDE_CDS
1516 void ClassLoader::initialize_shared_path(JavaThread* current) {
1517 if (CDSConfig::is_dumping_archive()) {
1518 ClassLoaderExt::setup_search_paths(current);
1519 }
1520 }
1521
1522 void ClassLoader::initialize_module_path(TRAPS) {
1523 if (CDSConfig::is_dumping_archive()) {
1524 ClassLoaderExt::setup_module_paths(THREAD);
1525 FileMapInfo::allocate_shared_path_table(CHECK);
1526 }
1527 }
1528
1529 // Helper function used by CDS code to get the number of module path
1530 // entries during shared classpath setup time.
1531 int ClassLoader::num_module_path_entries() {
1532 assert(CDSConfig::is_dumping_archive(), "sanity");
1533 int num_entries = 0;
1534 ClassPathEntry* e= ClassLoader::_module_path_entries;
1535 while (e != nullptr) {
1536 num_entries ++;
1537 e = e->next();
1538 }
1539 return num_entries;
1540 }
1541 #endif
1542
1543 jlong ClassLoader::classloader_time_ms() {
1544 return UsePerfData ?
1545 Management::ticks_to_ms(_perf_accumulated_time->get_value()) : -1;
1546 }
1547
1548 jlong ClassLoader::class_init_count() {
1549 return UsePerfData ? _perf_classes_inited->get_value() : -1;
1550 }
1551
1552 jlong ClassLoader::class_init_time_ms() {
1553 return UsePerfData ?
1554 Management::ticks_to_ms(_perf_class_init_time->get_value()) : -1;
1555 }
1556
1557 jlong ClassLoader::class_verify_time_ms() {
1558 return UsePerfData ?
1559 Management::ticks_to_ms(_perf_class_verify_time->get_value()) : -1;
1560 }
1561
1562 jlong ClassLoader::class_link_count() {
1563 return UsePerfData ? _perf_classes_linked->get_value() : -1;
1564 }
1565
1566 jlong ClassLoader::class_link_time_ms() {
1567 return UsePerfData ?
1568 Management::ticks_to_ms(_perf_class_link_time->get_value()) : -1;
1569 }
1570
1571 int ClassLoader::compute_Object_vtable() {
1572 // hardwired for JDK1.2 -- would need to duplicate class file parsing
1573 // code to determine actual value from file
1574 // Would be value '11' if finals were in vtable
1575 int JDK_1_2_Object_vtable_size = 5;
1576 return JDK_1_2_Object_vtable_size * vtableEntry::size();
1577 }
1578
1579
1580 void classLoader_init1() {
1581 EXCEPTION_MARK;
1582 ClassLoader::initialize(THREAD);
1583 if (HAS_PENDING_EXCEPTION) {
1584 vm_exit_during_initialization("ClassLoader::initialize() failed unexpectedly");
1585 }
1586 }
1587
1588 // Complete the ClassPathEntry setup for the boot loader
1589 void ClassLoader::classLoader_init2(JavaThread* current) {
1590 // Setup the list of module/path pairs for --patch-module processing
1591 // This must be done after the SymbolTable is created in order
1592 // to use fast_compare on module names instead of a string compare.
1593 if (Arguments::get_patch_mod_prefix() != nullptr) {
1594 setup_patch_mod_entries();
1595 }
1596
1597 // Create the ModuleEntry for java.base (must occur after setup_patch_mod_entries
1598 // to successfully determine if java.base has been patched)
1599 create_javabase();
1600
1601 // Setup the initial java.base/path pair for the exploded build entries.
1602 // As more modules are defined during module system initialization, more
1603 // entries will be added to the exploded build array.
1604 if (!has_jrt_entry()) {
1605 assert(!CDSConfig::is_dumping_archive(), "not supported with exploded module builds");
1606 assert(!CDSConfig::is_using_archive(), "UsedSharedSpaces not supported with exploded module builds");
1607 // Set up the boot loader's _exploded_entries list. Note that this gets
1608 // done before loading any classes, by the same thread that will
1609 // subsequently do the first class load. So, no lock is needed for this.
1610 assert(_exploded_entries == nullptr, "Should only get initialized once");
1611 _exploded_entries = new (mtModule)
1612 GrowableArray<ModuleClassPathList*>(EXPLODED_ENTRY_SIZE, mtModule);
1613 add_to_exploded_build_list(current, vmSymbols::java_base());
1614 }
1615 }
1616
1617 char* ClassLoader::get_canonical_path(const char* orig, Thread* thread) {
1618 assert(orig != nullptr, "bad arguments");
1619 // caller needs to allocate ResourceMark for the following output buffer
1620 char* canonical_path = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, JVM_MAXPATHLEN);
1621 ResourceMark rm(thread);
1622 // os::native_path writes into orig_copy
1623 char* orig_copy = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, strlen(orig)+1);
1624 strcpy(orig_copy, orig);
1625 if ((CanonicalizeEntry)(os::native_path(orig_copy), canonical_path, JVM_MAXPATHLEN) < 0) {
1626 return nullptr;
1627 }
1628 return canonical_path;
1629 }
1630
1631 void ClassLoader::create_javabase() {
1632 JavaThread* current = JavaThread::current();
1633
1634 // Create java.base's module entry for the boot
1635 // class loader prior to loading j.l.Object.
1636 ClassLoaderData* null_cld = ClassLoaderData::the_null_class_loader_data();
1637
1638 // Get module entry table
1639 ModuleEntryTable* null_cld_modules = null_cld->modules();
1640 if (null_cld_modules == nullptr) {
1641 vm_exit_during_initialization("No ModuleEntryTable for the boot class loader");
1642 }
1643
1644 {
1645 MutexLocker ml(current, Module_lock);
1646 if (ModuleEntryTable::javabase_moduleEntry() == nullptr) { // may have been inited by CDS.
1647 ModuleEntry* jb_module = null_cld_modules->locked_create_entry(Handle(),
1648 false, vmSymbols::java_base(), nullptr, nullptr, null_cld);
1649 if (jb_module == nullptr) {
1650 vm_exit_during_initialization("Unable to create ModuleEntry for " JAVA_BASE_NAME);
1651 }
1652 ModuleEntryTable::set_javabase_moduleEntry(jb_module);
1653 }
1654 }
1655 }
1656
1657 // Please keep following two functions at end of this file. With them placed at top or in middle of the file,
1658 // they could get inlined by aggressive compiler, an unknown trick, see bug 6966589.
1659 void PerfClassTraceTime::initialize() {
1660 if (!UsePerfData) return;
1661
1662 if (_eventp != nullptr) {
1663 // increment the event counter
1664 _eventp->inc();
1665 }
1666
1667 // stop the current active thread-local timer to measure inclusive time
1668 _prev_active_event = -1;
1669 for (int i=0; i < EVENT_TYPE_COUNT; i++) {
1670 if (_timers[i].is_active()) {
1671 assert(_prev_active_event == -1, "should have only one active timer");
1672 _prev_active_event = i;
1673 _timers[i].stop();
1674 }
1675 }
1676
1677 if (_recursion_counters == nullptr || (_recursion_counters[_event_type])++ == 0) {
1678 // start the inclusive timer if not recursively called
1679 _t.start();
1680 }
1681
1682 // start thread-local timer of the given event type
1683 if (!_timers[_event_type].is_active()) {
1684 _timers[_event_type].start();
1685 }
1686 }
1687
1688 PerfClassTraceTime::~PerfClassTraceTime() {
1689 if (!UsePerfData) return;
1690
1691 // stop the thread-local timer as the event completes
1692 // and resume the thread-local timer of the event next on the stack
1693 _timers[_event_type].stop();
1694 jlong selftime = _timers[_event_type].ticks();
1695
1696 if (_prev_active_event >= 0) {
1697 _timers[_prev_active_event].start();
1698 }
1699
1700 if (_recursion_counters != nullptr && --(_recursion_counters[_event_type]) > 0) return;
1701
1702 // increment the counters only on the leaf call
1703 _t.stop();
1704 _timep->inc(_t.ticks());
1705 if (_selftimep != nullptr) {
1706 _selftimep->inc(selftime);
1707 }
1708 // add all class loading related event selftime to the accumulated time counter
1709 ClassLoader::perf_accumulated_time()->inc(selftime);
1710
1711 // reset the timer
1712 _timers[_event_type].reset();
1713 }