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