1 /*
2 * Copyright (c) 1997, 2023, 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/filemap.hpp"
28 #include "classfile/classFileStream.hpp"
29 #include "classfile/classLoader.inline.hpp"
30 #include "classfile/classLoaderData.inline.hpp"
31 #include "classfile/classLoaderExt.hpp"
32 #include "classfile/classLoadInfo.hpp"
33 #include "classfile/javaClasses.hpp"
34 #include "classfile/moduleEntry.hpp"
35 #include "classfile/modules.hpp"
36 #include "classfile/packageEntry.hpp"
37 #include "classfile/klassFactory.hpp"
38 #include "classfile/symbolTable.hpp"
39 #include "classfile/systemDictionary.hpp"
40 #include "classfile/systemDictionaryShared.hpp"
41 #include "classfile/vmClasses.hpp"
42 #include "classfile/vmSymbols.hpp"
43 #include "compiler/compileBroker.hpp"
44 #include "interpreter/bytecodeStream.hpp"
45 #include "interpreter/oopMapCache.hpp"
46 #include "jimage.hpp"
47 #include "jvm.h"
48 #include "logging/log.hpp"
49 #include "logging/logStream.hpp"
50 #include "logging/logTag.hpp"
51 #include "memory/allocation.inline.hpp"
52 #include "memory/oopFactory.hpp"
53 #include "memory/resourceArea.hpp"
54 #include "memory/universe.hpp"
55 #include "oops/instanceKlass.hpp"
56 #include "oops/instanceRefKlass.hpp"
57 #include "oops/klass.inline.hpp"
58 #include "oops/method.inline.hpp"
59 #include "oops/objArrayOop.inline.hpp"
60 #include "oops/oop.inline.hpp"
61 #include "oops/symbol.hpp"
62 #include "prims/jvm_misc.hpp"
63 #include "runtime/arguments.hpp"
64 #include "runtime/handles.inline.hpp"
65 #include "runtime/init.hpp"
66 #include "runtime/interfaceSupport.inline.hpp"
67 #include "runtime/java.hpp"
68 #include "runtime/javaCalls.hpp"
69 #include "runtime/os.hpp"
70 #include "runtime/perfData.hpp"
71 #include "runtime/threadCritical.hpp"
72 #include "runtime/timer.hpp"
73 #include "runtime/vm_version.hpp"
74 #include "services/management.hpp"
75 #include "services/threadService.hpp"
76 #include "utilities/checkedCast.hpp"
77 #include "utilities/classpathStream.hpp"
78 #include "utilities/events.hpp"
79 #include "utilities/macros.hpp"
80 #include "utilities/utf8.hpp"
81
82 // Entry point in java.dll for path canonicalization
83
84 typedef int (*canonicalize_fn_t)(const char *orig, char *out, int len);
85
86 static canonicalize_fn_t CanonicalizeEntry = nullptr;
87
88 // Entry points in zip.dll for loading zip/jar file entries
89
90 typedef void * * (*ZipOpen_t)(const char *name, char **pmsg);
91 typedef void (*ZipClose_t)(jzfile *zip);
92 typedef jzentry* (*FindEntry_t)(jzfile *zip, const char *name, jint *sizeP, jint *nameLen);
93 typedef jboolean (*ReadEntry_t)(jzfile *zip, jzentry *entry, unsigned char *buf, char *namebuf);
94 typedef jint (*Crc32_t)(jint crc, const jbyte *buf, jint len);
95
96 static ZipOpen_t ZipOpen = nullptr;
97 static ZipClose_t ZipClose = nullptr;
98 static FindEntry_t FindEntry = nullptr;
99 static ReadEntry_t ReadEntry = nullptr;
100 static Crc32_t Crc32 = nullptr;
101 int ClassLoader::_libzip_loaded = 0;
102 void* ClassLoader::_zip_handle = nullptr;
103
104 // Entry points for jimage.dll for loading jimage file entries
105
106 static JImageOpen_t JImageOpen = nullptr;
107 static JImageClose_t JImageClose = nullptr;
108 static JImageFindResource_t JImageFindResource = nullptr;
109 static JImageGetResource_t JImageGetResource = nullptr;
110
111 // JimageFile pointer, or null if exploded JDK build.
112 static JImageFile* JImage_file = nullptr;
113
114 // Globals
115
116 PerfCounter* ClassLoader::_perf_accumulated_time = nullptr;
117 PerfCounter* ClassLoader::_perf_classes_inited = nullptr;
118 PerfCounter* ClassLoader::_perf_class_init_time = nullptr;
119 PerfCounter* ClassLoader::_perf_class_init_selftime = nullptr;
120 PerfCounter* ClassLoader::_perf_classes_verified = nullptr;
121 PerfCounter* ClassLoader::_perf_class_verify_time = nullptr;
122 PerfCounter* ClassLoader::_perf_class_verify_selftime = nullptr;
123 PerfCounter* ClassLoader::_perf_classes_linked = nullptr;
124 PerfCounter* ClassLoader::_perf_class_link_time = nullptr;
125 PerfCounter* ClassLoader::_perf_class_link_selftime = nullptr;
126 PerfCounter* ClassLoader::_perf_sys_class_lookup_time = nullptr;
127 PerfCounter* ClassLoader::_perf_shared_classload_time = nullptr;
128 PerfCounter* ClassLoader::_perf_sys_classload_time = nullptr;
129 PerfCounter* ClassLoader::_perf_app_classload_time = nullptr;
130 PerfCounter* ClassLoader::_perf_app_classload_selftime = nullptr;
131 PerfCounter* ClassLoader::_perf_app_classload_count = nullptr;
132 PerfCounter* ClassLoader::_perf_define_appclasses = nullptr;
133 PerfCounter* ClassLoader::_perf_define_appclass_time = nullptr;
134 PerfCounter* ClassLoader::_perf_define_appclass_selftime = nullptr;
135 PerfCounter* ClassLoader::_perf_app_classfile_bytes_read = nullptr;
136 PerfCounter* ClassLoader::_perf_sys_classfile_bytes_read = nullptr;
137 PerfCounter* ClassLoader::_unsafe_defineClassCallCounter = nullptr;
138
139 GrowableArray<ModuleClassPathList*>* ClassLoader::_patch_mod_entries = nullptr;
140 GrowableArray<ModuleClassPathList*>* ClassLoader::_exploded_entries = nullptr;
141 ClassPathEntry* ClassLoader::_jrt_entry = nullptr;
142
143 ClassPathEntry* volatile ClassLoader::_first_append_entry_list = nullptr;
144 ClassPathEntry* volatile ClassLoader::_last_append_entry = nullptr;
145 #if INCLUDE_CDS
146 ClassPathEntry* ClassLoader::_app_classpath_entries = nullptr;
147 ClassPathEntry* ClassLoader::_last_app_classpath_entry = nullptr;
148 ClassPathEntry* ClassLoader::_module_path_entries = nullptr;
149 ClassPathEntry* ClassLoader::_last_module_path_entry = nullptr;
150 #endif
151
152 // helper routines
153 bool string_starts_with(const char* str, const char* str_to_find) {
154 size_t str_len = strlen(str);
155 size_t str_to_find_len = strlen(str_to_find);
156 if (str_to_find_len > str_len) {
157 return false;
158 }
159 return (strncmp(str, str_to_find, str_to_find_len) == 0);
160 }
161
162 static const char* get_jimage_version_string() {
163 static char version_string[10] = "";
164 if (version_string[0] == '\0') {
165 jio_snprintf(version_string, sizeof(version_string), "%d.%d",
166 VM_Version::vm_major_version(), VM_Version::vm_minor_version());
167 }
168 return (const char*)version_string;
169 }
170
171 bool ClassLoader::string_ends_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_len - str_to_find_len), str_to_find, str_to_find_len) == 0);
178 }
179
180 // Used to obtain the package name from a fully qualified class name.
181 Symbol* ClassLoader::package_from_class_name(const Symbol* name, bool* bad_class_name) {
182 if (name == nullptr) {
183 if (bad_class_name != nullptr) {
184 *bad_class_name = true;
185 }
186 return nullptr;
187 }
188
189 int utf_len = name->utf8_length();
190 const jbyte* base = (const jbyte*)name->base();
191 const jbyte* start = base;
192 const jbyte* end = UTF8::strrchr(start, utf_len, JVM_SIGNATURE_SLASH);
193 if (end == nullptr) {
194 return nullptr;
195 }
196 // Skip over '['s
197 if (*start == JVM_SIGNATURE_ARRAY) {
198 do {
199 start++;
200 } while (start < end && *start == JVM_SIGNATURE_ARRAY);
201
202 // Fully qualified class names should not contain a 'L'.
203 // Set bad_class_name to true to indicate that the package name
204 // could not be obtained due to an error condition.
205 // In this situation, is_same_class_package returns false.
206 if (*start == JVM_SIGNATURE_CLASS || *start == JVM_SIGNATURE_PRIMITIVE_OBJECT) {
207 if (bad_class_name != nullptr) {
208 *bad_class_name = true;
209 }
210 return nullptr;
211 }
212 }
213 // A class name could have just the slash character in the name,
214 // in which case start > end
215 if (start >= end) {
216 // No package name
217 if (bad_class_name != nullptr) {
218 *bad_class_name = true;
219 }
220 return nullptr;
221 }
222 return SymbolTable::new_symbol(name, pointer_delta_as_int(start, base), pointer_delta_as_int(end, base));
223 }
224
225 // Given a fully qualified package name, find its defining package in the class loader's
226 // package entry table.
227 PackageEntry* ClassLoader::get_package_entry(Symbol* pkg_name, ClassLoaderData* loader_data) {
228 if (pkg_name == nullptr) {
229 return nullptr;
230 }
231 PackageEntryTable* pkgEntryTable = loader_data->packages();
232 return pkgEntryTable->lookup_only(pkg_name);
233 }
234
235 const char* ClassPathEntry::copy_path(const char* path) {
236 char* copy = NEW_C_HEAP_ARRAY(char, strlen(path)+1, mtClass);
237 strcpy(copy, path);
238 return copy;
239 }
240
241 ClassPathDirEntry::~ClassPathDirEntry() {
242 FREE_C_HEAP_ARRAY(char, _dir);
243 }
244
245 ClassFileStream* ClassPathDirEntry::open_stream(JavaThread* current, const char* name) {
246 // construct full path name
247 assert((_dir != nullptr) && (name != nullptr), "sanity");
248 size_t path_len = strlen(_dir) + strlen(name) + strlen(os::file_separator()) + 1;
249 char* path = NEW_RESOURCE_ARRAY_IN_THREAD(current, char, path_len);
250 int len = jio_snprintf(path, path_len, "%s%s%s", _dir, os::file_separator(), name);
251 assert(len == (int)(path_len - 1), "sanity");
252 // check if file exists
253 struct stat st;
254 if (os::stat(path, &st) == 0) {
255 // found file, open it
256 int file_handle = os::open(path, 0, 0);
257 if (file_handle != -1) {
258 // read contents into resource array
259 u1* buffer = NEW_RESOURCE_ARRAY_IN_THREAD(current, u1, st.st_size);
260 size_t num_read = ::read(file_handle, (char*) buffer, st.st_size);
261 // close file
262 ::close(file_handle);
263 // construct ClassFileStream
264 if (num_read == (size_t)st.st_size) {
265 if (UsePerfData) {
266 ClassLoader::perf_sys_classfile_bytes_read()->inc(num_read);
267 }
268 #ifdef ASSERT
269 // Freeing path is a no-op here as buffer prevents it from being reclaimed. But we keep it for
270 // debug builds so that we guard against use-after-free bugs.
271 FREE_RESOURCE_ARRAY_IN_THREAD(current, char, path, path_len);
272 #endif
273 // We don't verify the length of the classfile stream fits in an int, but this is the
274 // bootloader so we have control of this.
275 // Resource allocated
276 return new ClassFileStream(buffer,
277 checked_cast<int>(st.st_size),
278 _dir,
279 ClassFileStream::verify);
280 }
281 }
282 }
283 FREE_RESOURCE_ARRAY_IN_THREAD(current, char, path, path_len);
284 return nullptr;
285 }
286
287 ClassPathZipEntry::ClassPathZipEntry(jzfile* zip, const char* zip_name,
288 bool is_boot_append, bool from_class_path_attr) : ClassPathEntry() {
289 _zip = zip;
290 _zip_name = copy_path(zip_name);
291 _from_class_path_attr = from_class_path_attr;
292 }
293
294 ClassPathZipEntry::~ClassPathZipEntry() {
295 (*ZipClose)(_zip);
296 FREE_C_HEAP_ARRAY(char, _zip_name);
297 }
298
299 u1* ClassPathZipEntry::open_entry(JavaThread* current, const char* name, jint* filesize, bool nul_terminate) {
300 // enable call to C land
301 ThreadToNativeFromVM ttn(current);
302 // check whether zip archive contains name
303 jint name_len;
304 jzentry* entry = (*FindEntry)(_zip, name, filesize, &name_len);
305 if (entry == nullptr) return nullptr;
306 u1* buffer;
307 char name_buf[128];
308 char* filename;
309 if (name_len < 128) {
310 filename = name_buf;
311 } else {
312 filename = NEW_RESOURCE_ARRAY(char, name_len + 1);
313 }
314
315 // read contents into resource array
316 size_t size = (uint32_t)(*filesize);
317 if (nul_terminate) {
318 if (sizeof(size) == sizeof(uint32_t) && size == UINT_MAX) {
319 return nullptr; // 32-bit integer overflow will occur.
320 }
321 size++;
322 }
323 buffer = NEW_RESOURCE_ARRAY(u1, size);
324 if (!(*ReadEntry)(_zip, entry, buffer, filename)) return nullptr;
325
326 // return result
327 if (nul_terminate) {
328 buffer[size - 1] = 0;
329 }
330 return buffer;
331 }
332
333 ClassFileStream* ClassPathZipEntry::open_stream(JavaThread* current, const char* name) {
334 jint filesize;
335 u1* buffer = open_entry(current, name, &filesize, false);
336 if (buffer == nullptr) {
337 return nullptr;
338 }
339 if (UsePerfData) {
340 ClassLoader::perf_sys_classfile_bytes_read()->inc(filesize);
341 }
342 // Resource allocated
343 return new ClassFileStream(buffer,
344 filesize,
345 _zip_name,
346 ClassFileStream::verify);
347 }
348
349 DEBUG_ONLY(ClassPathImageEntry* ClassPathImageEntry::_singleton = nullptr;)
350
351 JImageFile* ClassPathImageEntry::jimage() const {
352 return JImage_file;
353 }
354
355 JImageFile* ClassPathImageEntry::jimage_non_null() const {
356 assert(ClassLoader::has_jrt_entry(), "must be");
357 assert(jimage() != nullptr, "should have been opened by ClassLoader::lookup_vm_options "
358 "and remained throughout normal JVM lifetime");
359 return jimage();
360 }
361
362 void ClassPathImageEntry::close_jimage() {
363 if (jimage() != nullptr) {
364 (*JImageClose)(jimage());
365 JImage_file = nullptr;
366 }
367 }
368
369 ClassPathImageEntry::ClassPathImageEntry(JImageFile* jimage, const char* name) :
370 ClassPathEntry() {
371 guarantee(jimage != nullptr, "jimage file is null");
372 guarantee(name != nullptr, "jimage file name is null");
373 assert(_singleton == nullptr, "VM supports only one jimage");
374 DEBUG_ONLY(_singleton = this);
375 size_t len = strlen(name) + 1;
376 _name = copy_path(name);
377 }
378
379 ClassFileStream* ClassPathImageEntry::open_stream(JavaThread* current, const char* name) {
380 return open_stream_for_loader(current, name, ClassLoaderData::the_null_class_loader_data());
381 }
382
383 // For a class in a named module, look it up in the jimage file using this syntax:
384 // /<module-name>/<package-name>/<base-class>
385 //
386 // Assumptions:
387 // 1. There are no unnamed modules in the jimage file.
388 // 2. A package is in at most one module in the jimage file.
389 //
390 ClassFileStream* ClassPathImageEntry::open_stream_for_loader(JavaThread* current, const char* name, ClassLoaderData* loader_data) {
391 jlong size;
392 JImageLocationRef location = (*JImageFindResource)(jimage_non_null(), "", get_jimage_version_string(), name, &size);
393
394 if (location == 0) {
395 TempNewSymbol class_name = SymbolTable::new_symbol(name);
396 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
397
398 if (pkg_name != nullptr) {
399 if (!Universe::is_module_initialized()) {
400 location = (*JImageFindResource)(jimage_non_null(), JAVA_BASE_NAME, get_jimage_version_string(), name, &size);
401 } else {
402 PackageEntry* package_entry = ClassLoader::get_package_entry(pkg_name, loader_data);
403 if (package_entry != nullptr) {
404 ResourceMark rm(current);
405 // Get the module name
406 ModuleEntry* module = package_entry->module();
407 assert(module != nullptr, "Boot classLoader package missing module");
408 assert(module->is_named(), "Boot classLoader package is in unnamed module");
409 const char* module_name = module->name()->as_C_string();
410 if (module_name != nullptr) {
411 location = (*JImageFindResource)(jimage_non_null(), module_name, get_jimage_version_string(), name, &size);
412 }
413 }
414 }
415 }
416 }
417 if (location != 0) {
418 if (UsePerfData) {
419 ClassLoader::perf_sys_classfile_bytes_read()->inc(size);
420 }
421 char* data = NEW_RESOURCE_ARRAY(char, size);
422 (*JImageGetResource)(jimage_non_null(), location, data, size);
423 // Resource allocated
424 assert(this == (ClassPathImageEntry*)ClassLoader::get_jrt_entry(), "must be");
425 return new ClassFileStream((u1*)data,
426 checked_cast<int>(size),
427 _name,
428 ClassFileStream::verify,
429 true); // from_boot_loader_modules_image
430 }
431
432 return nullptr;
433 }
434
435 JImageLocationRef ClassLoader::jimage_find_resource(JImageFile* jf,
436 const char* module_name,
437 const char* file_name,
438 jlong &size) {
439 return ((*JImageFindResource)(jf, module_name, get_jimage_version_string(), file_name, &size));
440 }
441
442 bool ClassPathImageEntry::is_modules_image() const {
443 assert(this == _singleton, "VM supports a single jimage");
444 assert(this == (ClassPathImageEntry*)ClassLoader::get_jrt_entry(), "must be used for jrt entry");
445 return true;
446 }
447
448 #if INCLUDE_CDS
449 void ClassLoader::exit_with_path_failure(const char* error, const char* message) {
450 Arguments::assert_is_dumping_archive();
451 tty->print_cr("Hint: enable -Xlog:class+path=info to diagnose the failure");
452 vm_exit_during_initialization(error, message);
453 }
454 #endif
455
456 ModuleClassPathList::ModuleClassPathList(Symbol* module_name) {
457 _module_name = module_name;
458 _module_first_entry = nullptr;
459 _module_last_entry = nullptr;
460 }
461
462 ModuleClassPathList::~ModuleClassPathList() {
463 // Clean out each ClassPathEntry on list
464 ClassPathEntry* e = _module_first_entry;
465 while (e != nullptr) {
466 ClassPathEntry* next_entry = e->next();
467 delete e;
468 e = next_entry;
469 }
470 }
471
472 void ModuleClassPathList::add_to_list(ClassPathEntry* new_entry) {
473 if (new_entry != nullptr) {
474 if (_module_last_entry == nullptr) {
475 _module_first_entry = _module_last_entry = new_entry;
476 } else {
477 _module_last_entry->set_next(new_entry);
478 _module_last_entry = new_entry;
479 }
480 }
481 }
482
483 void ClassLoader::trace_class_path(const char* msg, const char* name) {
484 LogTarget(Info, class, path) lt;
485 if (lt.is_enabled()) {
486 LogStream ls(lt);
487 if (msg) {
488 ls.print("%s", msg);
489 }
490 if (name) {
491 if (strlen(name) < 256) {
492 ls.print("%s", name);
493 } else {
494 // For very long paths, we need to print each character separately,
495 // as print_cr() has a length limit
496 while (name[0] != '\0') {
497 ls.print("%c", name[0]);
498 name++;
499 }
500 }
501 }
502 ls.cr();
503 }
504 }
505
506 void ClassLoader::setup_bootstrap_search_path(JavaThread* current) {
507 const char* bootcp = Arguments::get_boot_class_path();
508 assert(bootcp != nullptr, "Boot class path must not be nullptr");
509 if (PrintSharedArchiveAndExit) {
510 // Don't print bootcp - this is the bootcp of this current VM process, not necessarily
511 // the same as the boot classpath of the shared archive.
512 } else {
513 trace_class_path("bootstrap loader class path=", bootcp);
514 }
515 setup_bootstrap_search_path_impl(current, bootcp);
516 }
517
518 #if INCLUDE_CDS
519 void ClassLoader::setup_app_search_path(JavaThread* current, const char *class_path) {
520 Arguments::assert_is_dumping_archive();
521
522 ResourceMark rm(current);
523 ClasspathStream cp_stream(class_path);
524
525 while (cp_stream.has_next()) {
526 const char* path = cp_stream.get_next();
527 update_class_path_entry_list(current, path, /* check_for_duplicates */ true,
528 /* is_boot_append */ false, /* from_class_path_attr */ false);
529 }
530 }
531
532 void ClassLoader::add_to_module_path_entries(const char* path,
533 ClassPathEntry* entry) {
534 assert(entry != nullptr, "ClassPathEntry should not be nullptr");
535 Arguments::assert_is_dumping_archive();
536
537 // The entry does not exist, add to the list
538 if (_module_path_entries == nullptr) {
539 assert(_last_module_path_entry == nullptr, "Sanity");
540 _module_path_entries = _last_module_path_entry = entry;
541 } else {
542 _last_module_path_entry->set_next(entry);
543 _last_module_path_entry = entry;
544 }
545 }
546
547 // Add a module path to the _module_path_entries list.
548 void ClassLoader::setup_module_search_path(JavaThread* current, const char* path) {
549 Arguments::assert_is_dumping_archive();
550 struct stat st;
551 if (os::stat(path, &st) != 0) {
552 tty->print_cr("os::stat error %d (%s). CDS dump aborted (path was \"%s\").",
553 errno, os::errno_name(errno), path);
554 vm_exit_during_initialization();
555 }
556 // File or directory found
557 ClassPathEntry* new_entry = nullptr;
558 new_entry = create_class_path_entry(current, path, &st,
559 false /*is_boot_append */, false /* from_class_path_attr */);
560 if (new_entry != nullptr) {
561 add_to_module_path_entries(path, new_entry);
562 }
563 }
564
565 #endif // INCLUDE_CDS
566
567 void ClassLoader::close_jrt_image() {
568 // Not applicable for exploded builds
569 if (!ClassLoader::has_jrt_entry()) return;
570 _jrt_entry->close_jimage();
571 }
572
573 // Construct the array of module/path pairs as specified to --patch-module
574 // for the boot loader to search ahead of the jimage, if the class being
575 // loaded is defined to a module that has been specified to --patch-module.
576 void ClassLoader::setup_patch_mod_entries() {
577 JavaThread* current = JavaThread::current();
578 GrowableArray<ModulePatchPath*>* patch_mod_args = Arguments::get_patch_mod_prefix();
579 int num_of_entries = patch_mod_args->length();
580
581 // Set up the boot loader's _patch_mod_entries list
582 _patch_mod_entries = new (mtModule) GrowableArray<ModuleClassPathList*>(num_of_entries, mtModule);
583
584 for (int i = 0; i < num_of_entries; i++) {
585 const char* module_name = (patch_mod_args->at(i))->module_name();
586 Symbol* const module_sym = SymbolTable::new_symbol(module_name);
587 assert(module_sym != nullptr, "Failed to obtain Symbol for module name");
588 ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
589
590 char* class_path = (patch_mod_args->at(i))->path_string();
591 ResourceMark rm(current);
592 ClasspathStream cp_stream(class_path);
593
594 while (cp_stream.has_next()) {
595 const char* path = cp_stream.get_next();
596 struct stat st;
597 if (os::stat(path, &st) == 0) {
598 // File or directory found
599 ClassPathEntry* new_entry = create_class_path_entry(current, path, &st, false, false);
600 // If the path specification is valid, enter it into this module's list
601 if (new_entry != nullptr) {
602 module_cpl->add_to_list(new_entry);
603 }
604 }
605 }
606
607 // Record the module into the list of --patch-module entries only if
608 // valid ClassPathEntrys have been created
609 if (module_cpl->module_first_entry() != nullptr) {
610 _patch_mod_entries->push(module_cpl);
611 }
612 }
613 }
614
615 // Determine whether the module has been patched via the command-line
616 // option --patch-module
617 bool ClassLoader::is_in_patch_mod_entries(Symbol* module_name) {
618 if (_patch_mod_entries != nullptr && _patch_mod_entries->is_nonempty()) {
619 int table_len = _patch_mod_entries->length();
620 for (int i = 0; i < table_len; i++) {
621 ModuleClassPathList* patch_mod = _patch_mod_entries->at(i);
622 if (module_name->fast_compare(patch_mod->module_name()) == 0) {
623 return true;
624 }
625 }
626 }
627 return false;
628 }
629
630 // Set up the _jrt_entry if present and boot append path
631 void ClassLoader::setup_bootstrap_search_path_impl(JavaThread* current, const char *class_path) {
632 ResourceMark rm(current);
633 ClasspathStream cp_stream(class_path);
634 bool set_base_piece = true;
635
636 #if INCLUDE_CDS
637 if (Arguments::is_dumping_archive()) {
638 if (!Arguments::has_jimage()) {
639 vm_exit_during_initialization("CDS is not supported in exploded JDK build", nullptr);
640 }
641 }
642 #endif
643
644 while (cp_stream.has_next()) {
645 const char* path = cp_stream.get_next();
646
647 if (set_base_piece) {
648 // The first time through the bootstrap_search setup, it must be determined
649 // what the base or core piece of the boot loader search is. Either a java runtime
650 // image is present or this is an exploded module build situation.
651 assert(string_ends_with(path, MODULES_IMAGE_NAME) || string_ends_with(path, JAVA_BASE_NAME),
652 "Incorrect boot loader search path, no java runtime image or " JAVA_BASE_NAME " exploded build");
653 struct stat st;
654 if (os::stat(path, &st) == 0) {
655 // Directory found
656 if (JImage_file != nullptr) {
657 assert(Arguments::has_jimage(), "sanity check");
658 const char* canonical_path = get_canonical_path(path, current);
659 assert(canonical_path != nullptr, "canonical_path issue");
660
661 _jrt_entry = new ClassPathImageEntry(JImage_file, canonical_path);
662 assert(_jrt_entry != nullptr && _jrt_entry->is_modules_image(), "No java runtime image present");
663 assert(_jrt_entry->jimage() != nullptr, "No java runtime image");
664 } // else it's an exploded build.
665 } else {
666 // If path does not exist, exit
667 vm_exit_during_initialization("Unable to establish the boot loader search path", path);
668 }
669 set_base_piece = false;
670 } else {
671 // Every entry on the boot class path after the initial base piece,
672 // which is set by os::set_boot_path(), is considered an appended entry.
673 update_class_path_entry_list(current, path, /* check_for_duplicates */ false,
674 /* is_boot_append */ true, /* from_class_path_attr */ false);
675 }
676 }
677 }
678
679 // Gets the exploded path for the named module. The memory for the path
680 // is allocated on the C heap if `c_heap` is true otherwise in the resource area.
681 static const char* get_exploded_module_path(const char* module_name, bool c_heap) {
682 const char *home = Arguments::get_java_home();
683 const char file_sep = os::file_separator()[0];
684 // 10 represents the length of "modules" + 2 file separators + \0
685 size_t len = strlen(home) + strlen(module_name) + 10;
686 char *path = c_heap ? NEW_C_HEAP_ARRAY(char, len, mtModule) : NEW_RESOURCE_ARRAY(char, len);
687 jio_snprintf(path, len, "%s%cmodules%c%s", home, file_sep, file_sep, module_name);
688 return path;
689 }
690
691 // During an exploded modules build, each module defined to the boot loader
692 // will be added to the ClassLoader::_exploded_entries array.
693 void ClassLoader::add_to_exploded_build_list(JavaThread* current, Symbol* module_sym) {
694 assert(!ClassLoader::has_jrt_entry(), "Exploded build not applicable");
695 assert(_exploded_entries != nullptr, "_exploded_entries was not initialized");
696
697 // Find the module's symbol
698 ResourceMark rm(current);
699 const char *module_name = module_sym->as_C_string();
700 const char *path = get_exploded_module_path(module_name, false);
701
702 struct stat st;
703 if (os::stat(path, &st) == 0) {
704 // Directory found
705 ClassPathEntry* new_entry = create_class_path_entry(current, path, &st, false, false);
706
707 // If the path specification is valid, enter it into this module's list.
708 // There is no need to check for duplicate modules in the exploded entry list,
709 // since no two modules with the same name can be defined to the boot loader.
710 // This is checked at module definition time in Modules::define_module.
711 if (new_entry != nullptr) {
712 ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
713 module_cpl->add_to_list(new_entry);
714 {
715 MutexLocker ml(current, Module_lock);
716 _exploded_entries->push(module_cpl);
717 }
718 log_info(class, load)("path: %s", path);
719 }
720 }
721 }
722
723 jzfile* ClassLoader::open_zip_file(const char* canonical_path, char** error_msg, JavaThread* thread) {
724 // enable call to C land
725 ThreadToNativeFromVM ttn(thread);
726 HandleMark hm(thread);
727 load_zip_library_if_needed();
728 return (*ZipOpen)(canonical_path, error_msg);
729 }
730
731 ClassPathEntry* ClassLoader::create_class_path_entry(JavaThread* current,
732 const char *path, const struct stat* st,
733 bool is_boot_append,
734 bool from_class_path_attr) {
735 ClassPathEntry* new_entry = nullptr;
736 if ((st->st_mode & S_IFMT) == S_IFREG) {
737 ResourceMark rm(current);
738 // Regular file, should be a zip file
739 // Canonicalized filename
740 const char* canonical_path = get_canonical_path(path, current);
741 if (canonical_path == nullptr) {
742 return nullptr;
743 }
744 char* error_msg = nullptr;
745 jzfile* zip = open_zip_file(canonical_path, &error_msg, current);
746 if (zip != nullptr && error_msg == nullptr) {
747 new_entry = new ClassPathZipEntry(zip, path, is_boot_append, from_class_path_attr);
748 } else {
749 #if INCLUDE_CDS
750 ClassLoaderExt::set_has_non_jar_in_classpath();
751 #endif
752 return nullptr;
753 }
754 log_info(class, path)("opened: %s", path);
755 log_info(class, load)("opened: %s", path);
756 } else {
757 // Directory
758 new_entry = new ClassPathDirEntry(path);
759 log_info(class, load)("path: %s", path);
760 }
761 return new_entry;
762 }
763
764
765 // Create a class path zip entry for a given path (return null if not found
766 // or zip/JAR file cannot be opened)
767 ClassPathZipEntry* ClassLoader::create_class_path_zip_entry(const char *path, bool is_boot_append) {
768 // check for a regular file
769 struct stat st;
770 if (os::stat(path, &st) == 0) {
771 if ((st.st_mode & S_IFMT) == S_IFREG) {
772 JavaThread* thread = JavaThread::current();
773 ResourceMark rm(thread);
774 const char* canonical_path = get_canonical_path(path, thread);
775 if (canonical_path != nullptr) {
776 char* error_msg = nullptr;
777 jzfile* zip = open_zip_file(canonical_path, &error_msg, thread);
778 if (zip != nullptr && error_msg == nullptr) {
779 // create using canonical path
780 return new ClassPathZipEntry(zip, canonical_path, is_boot_append, false);
781 }
782 }
783 }
784 }
785 return nullptr;
786 }
787
788 // The boot append entries are added with a lock, and read lock free.
789 void ClassLoader::add_to_boot_append_entries(ClassPathEntry *new_entry) {
790 if (new_entry != nullptr) {
791 MutexLocker ml(Bootclasspath_lock, Mutex::_no_safepoint_check_flag);
792 if (_last_append_entry == nullptr) {
793 _last_append_entry = new_entry;
794 assert(first_append_entry() == nullptr, "boot loader's append class path entry list not empty");
795 Atomic::release_store(&_first_append_entry_list, new_entry);
796 } else {
797 _last_append_entry->set_next(new_entry);
798 _last_append_entry = new_entry;
799 }
800 }
801 }
802
803 // Record the path entries specified in -cp during dump time. The recorded
804 // information will be used at runtime for loading the archived app classes.
805 //
806 // Note that at dump time, ClassLoader::_app_classpath_entries are NOT used for
807 // loading app classes. Instead, the app class are loaded by the
808 // jdk/internal/loader/ClassLoaders$AppClassLoader instance.
809 bool ClassLoader::add_to_app_classpath_entries(JavaThread* current,
810 ClassPathEntry* entry,
811 bool check_for_duplicates) {
812 #if INCLUDE_CDS
813 assert(entry != nullptr, "ClassPathEntry should not be nullptr");
814 ClassPathEntry* e = _app_classpath_entries;
815 if (check_for_duplicates) {
816 while (e != nullptr) {
817 if (strcmp(e->name(), entry->name()) == 0) {
818 // entry already exists
819 return false;
820 }
821 e = e->next();
822 }
823 }
824
825 // The entry does not exist, add to the list
826 if (_app_classpath_entries == nullptr) {
827 assert(_last_app_classpath_entry == nullptr, "Sanity");
828 _app_classpath_entries = _last_app_classpath_entry = entry;
829 } else {
830 _last_app_classpath_entry->set_next(entry);
831 _last_app_classpath_entry = entry;
832 }
833
834 if (entry->is_jar_file()) {
835 ClassLoaderExt::process_jar_manifest(current, entry);
836 }
837 #endif
838 return true;
839 }
840
841 // Returns true IFF the file/dir exists and the entry was successfully created.
842 bool ClassLoader::update_class_path_entry_list(JavaThread* current,
843 const char *path,
844 bool check_for_duplicates,
845 bool is_boot_append,
846 bool from_class_path_attr) {
847 struct stat st;
848 if (os::stat(path, &st) == 0) {
849 // File or directory found
850 ClassPathEntry* new_entry = nullptr;
851 new_entry = create_class_path_entry(current, path, &st, is_boot_append, from_class_path_attr);
852 if (new_entry == nullptr) {
853 return false;
854 }
855
856 // Do not reorder the bootclasspath which would break get_system_package().
857 // Add new entry to linked list
858 if (is_boot_append) {
859 add_to_boot_append_entries(new_entry);
860 } else {
861 if (!add_to_app_classpath_entries(current, new_entry, check_for_duplicates)) {
862 // new_entry is not saved, free it now
863 delete new_entry;
864 }
865 }
866 return true;
867 } else {
868 return false;
869 }
870 }
871
872 static void print_module_entry_table(const GrowableArray<ModuleClassPathList*>* const module_list) {
873 ResourceMark rm;
874 int num_of_entries = module_list->length();
875 for (int i = 0; i < num_of_entries; i++) {
876 ClassPathEntry* e;
877 ModuleClassPathList* mpl = module_list->at(i);
878 tty->print("%s=", mpl->module_name()->as_C_string());
879 e = mpl->module_first_entry();
880 while (e != nullptr) {
881 tty->print("%s", e->name());
882 e = e->next();
883 if (e != nullptr) {
884 tty->print("%s", os::path_separator());
885 }
886 }
887 tty->print(" ;");
888 }
889 }
890
891 void ClassLoader::print_bootclasspath() {
892 ClassPathEntry* e;
893 tty->print("[bootclasspath= ");
894
895 // Print --patch-module module/path specifications first
896 if (_patch_mod_entries != nullptr) {
897 print_module_entry_table(_patch_mod_entries);
898 }
899
900 // [jimage | exploded modules build]
901 if (has_jrt_entry()) {
902 // Print the location of the java runtime image
903 tty->print("%s ;", _jrt_entry->name());
904 } else {
905 // Print exploded module build path specifications
906 if (_exploded_entries != nullptr) {
907 print_module_entry_table(_exploded_entries);
908 }
909 }
910
911 // appended entries
912 e = first_append_entry();
913 while (e != nullptr) {
914 tty->print("%s ;", e->name());
915 e = e->next();
916 }
917 tty->print_cr("]");
918 }
919
920 void* ClassLoader::dll_lookup(void* lib, const char* name, const char* path) {
921 void* func = os::dll_lookup(lib, name);
922 if (func == nullptr) {
923 char msg[256] = "";
924 jio_snprintf(msg, sizeof(msg), "Could not resolve \"%s\"", name);
925 vm_exit_during_initialization(msg, path);
926 }
927 return func;
928 }
929
930 void ClassLoader::load_java_library() {
931 assert(CanonicalizeEntry == nullptr, "should not load java library twice");
932 void *javalib_handle = os::native_java_library();
933 if (javalib_handle == nullptr) {
934 vm_exit_during_initialization("Unable to load java library", nullptr);
935 }
936
937 CanonicalizeEntry = CAST_TO_FN_PTR(canonicalize_fn_t, dll_lookup(javalib_handle, "JDK_Canonicalize", nullptr));
938 }
939
940 void ClassLoader::release_load_zip_library() {
941 ConditionalMutexLocker locker(Zip_lock, Zip_lock != nullptr, Monitor::_no_safepoint_check_flag);
942 if (_libzip_loaded == 0) {
943 load_zip_library();
944 Atomic::release_store(&_libzip_loaded, 1);
945 }
946 }
947
948 void ClassLoader::load_zip_library() {
949 assert(ZipOpen == nullptr, "should not load zip library twice");
950 char path[JVM_MAXPATHLEN];
951 char ebuf[1024];
952 if (os::dll_locate_lib(path, sizeof(path), Arguments::get_dll_dir(), "zip")) {
953 _zip_handle = os::dll_load(path, ebuf, sizeof ebuf);
954 }
955 if (_zip_handle == nullptr) {
956 vm_exit_during_initialization("Unable to load zip library", path);
957 }
958
959 ZipOpen = CAST_TO_FN_PTR(ZipOpen_t, dll_lookup(_zip_handle, "ZIP_Open", path));
960 ZipClose = CAST_TO_FN_PTR(ZipClose_t, dll_lookup(_zip_handle, "ZIP_Close", path));
961 FindEntry = CAST_TO_FN_PTR(FindEntry_t, dll_lookup(_zip_handle, "ZIP_FindEntry", path));
962 ReadEntry = CAST_TO_FN_PTR(ReadEntry_t, dll_lookup(_zip_handle, "ZIP_ReadEntry", path));
963 Crc32 = CAST_TO_FN_PTR(Crc32_t, dll_lookup(_zip_handle, "ZIP_CRC32", path));
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 load_zip_library_if_needed();
986 return (*Crc32)(crc, (const jbyte*)buf, len);
987 }
988
989 oop ClassLoader::get_system_package(const char* name, TRAPS) {
990 // Look up the name in the boot loader's package entry table.
991 if (name != nullptr) {
992 TempNewSymbol package_sym = SymbolTable::new_symbol(name);
993 // Look for the package entry in the boot loader's package entry table.
994 PackageEntry* package =
995 ClassLoaderData::the_null_class_loader_data()->packages()->lookup_only(package_sym);
996
997 // Return null if package does not exist or if no classes in that package
998 // have been loaded.
999 if (package != nullptr && package->has_loaded_class()) {
1000 ModuleEntry* module = package->module();
1001 if (module->location() != nullptr) {
1002 ResourceMark rm(THREAD);
1003 Handle ml = java_lang_String::create_from_str(
1004 module->location()->as_C_string(), THREAD);
1005 return ml();
1006 }
1007 // Return entry on boot loader class path.
1008 Handle cph = java_lang_String::create_from_str(
1009 ClassLoader::classpath_entry(package->classpath_index())->name(), THREAD);
1010 return cph();
1011 }
1012 }
1013 return nullptr;
1014 }
1015
1016 objArrayOop ClassLoader::get_system_packages(TRAPS) {
1017 ResourceMark rm(THREAD);
1018 // List of pointers to PackageEntrys that have loaded classes.
1019 PackageEntryTable* pe_table =
1020 ClassLoaderData::the_null_class_loader_data()->packages();
1021 GrowableArray<PackageEntry*>* loaded_class_pkgs = pe_table->get_system_packages();
1022
1023 // Allocate objArray and fill with java.lang.String
1024 objArrayOop r = oopFactory::new_objArray(vmClasses::String_klass(),
1025 loaded_class_pkgs->length(), CHECK_NULL);
1026 objArrayHandle result(THREAD, r);
1027 for (int x = 0; x < loaded_class_pkgs->length(); x++) {
1028 PackageEntry* package_entry = loaded_class_pkgs->at(x);
1029 Handle str = java_lang_String::create_from_symbol(package_entry->name(), CHECK_NULL);
1030 result->obj_at_put(x, str());
1031 }
1032 return result();
1033 }
1034
1035 // caller needs ResourceMark
1036 const char* ClassLoader::file_name_for_class_name(const char* class_name,
1037 int class_name_len) {
1038 assert(class_name != nullptr, "invariant");
1039 assert((int)strlen(class_name) == class_name_len, "invariant");
1040
1041 static const char class_suffix[] = ".class";
1042 size_t class_suffix_len = sizeof(class_suffix);
1043
1044 char* const file_name = NEW_RESOURCE_ARRAY(char,
1045 class_name_len +
1046 class_suffix_len); // includes term null
1047
1048 strncpy(file_name, class_name, class_name_len);
1049 strncpy(&file_name[class_name_len], class_suffix, class_suffix_len);
1050
1051 return file_name;
1052 }
1053
1054 ClassPathEntry* find_first_module_cpe(ModuleEntry* mod_entry,
1055 const GrowableArray<ModuleClassPathList*>* const module_list) {
1056 int num_of_entries = module_list->length();
1057 const Symbol* class_module_name = mod_entry->name();
1058
1059 // Loop through all the modules in either the patch-module or exploded entries looking for module
1060 for (int i = 0; i < num_of_entries; i++) {
1061 ModuleClassPathList* module_cpl = module_list->at(i);
1062 Symbol* module_cpl_name = module_cpl->module_name();
1063
1064 if (module_cpl_name->fast_compare(class_module_name) == 0) {
1065 // Class' module has been located.
1066 return module_cpl->module_first_entry();
1067 }
1068 }
1069 return nullptr;
1070 }
1071
1072
1073 // Search either the patch-module or exploded build entries for class.
1074 ClassFileStream* ClassLoader::search_module_entries(JavaThread* current,
1075 const GrowableArray<ModuleClassPathList*>* const module_list,
1076 const char* const class_name,
1077 const char* const file_name) {
1078 ClassFileStream* stream = nullptr;
1079
1080 // Find the class' defining module in the boot loader's module entry table
1081 TempNewSymbol class_name_symbol = SymbolTable::new_symbol(class_name);
1082 TempNewSymbol pkg_name = package_from_class_name(class_name_symbol);
1083 PackageEntry* pkg_entry = get_package_entry(pkg_name, ClassLoaderData::the_null_class_loader_data());
1084 ModuleEntry* mod_entry = (pkg_entry != nullptr) ? pkg_entry->module() : nullptr;
1085
1086 // If the module system has not defined java.base yet, then
1087 // classes loaded are assumed to be defined to java.base.
1088 // When java.base is eventually defined by the module system,
1089 // all packages of classes that have been previously loaded
1090 // are verified in ModuleEntryTable::verify_javabase_packages().
1091 if (!Universe::is_module_initialized() &&
1092 !ModuleEntryTable::javabase_defined() &&
1093 mod_entry == nullptr) {
1094 mod_entry = ModuleEntryTable::javabase_moduleEntry();
1095 }
1096
1097 // The module must be a named module
1098 ClassPathEntry* e = nullptr;
1099 if (mod_entry != nullptr && mod_entry->is_named()) {
1100 if (module_list == _exploded_entries) {
1101 // The exploded build entries can be added to at any time so a lock is
1102 // needed when searching them.
1103 assert(!ClassLoader::has_jrt_entry(), "Must be exploded build");
1104 MutexLocker ml(current, Module_lock);
1105 e = find_first_module_cpe(mod_entry, module_list);
1106 } else {
1107 e = find_first_module_cpe(mod_entry, module_list);
1108 }
1109 }
1110
1111 // Try to load the class from the module's ClassPathEntry list.
1112 while (e != nullptr) {
1113 stream = e->open_stream(current, file_name);
1114 // No context.check is required since CDS is not supported
1115 // for an exploded modules build or if --patch-module is specified.
1116 if (nullptr != stream) {
1117 return stream;
1118 }
1119 e = e->next();
1120 }
1121 // If the module was located, break out even if the class was not
1122 // located successfully from that module's ClassPathEntry list.
1123 // There will not be another valid entry for that module.
1124 return nullptr;
1125 }
1126
1127 // Called by the boot classloader to load classes
1128 InstanceKlass* ClassLoader::load_class(Symbol* name, bool search_append_only, TRAPS) {
1129 assert(name != nullptr, "invariant");
1130
1131 ResourceMark rm(THREAD);
1132 HandleMark hm(THREAD);
1133
1134 const char* const class_name = name->as_C_string();
1135
1136 EventMarkClassLoading m("Loading class %s", class_name);
1137
1138 const char* const file_name = file_name_for_class_name(class_name,
1139 name->utf8_length());
1140 assert(file_name != nullptr, "invariant");
1141
1142 // Lookup stream for parsing .class file
1143 ClassFileStream* stream = nullptr;
1144 s2 classpath_index = 0;
1145 ClassPathEntry* e = nullptr;
1146
1147 // If search_append_only is true, boot loader visibility boundaries are
1148 // set to be _first_append_entry to the end. This includes:
1149 // [-Xbootclasspath/a]; [jvmti appended entries]
1150 //
1151 // If search_append_only is false, boot loader visibility boundaries are
1152 // set to be the --patch-module entries plus the base piece. This includes:
1153 // [--patch-module=<module>=<file>(<pathsep><file>)*]; [jimage | exploded module build]
1154 //
1155
1156 // Load Attempt #1: --patch-module
1157 // Determine the class' defining module. If it appears in the _patch_mod_entries,
1158 // attempt to load the class from those locations specific to the module.
1159 // Specifications to --patch-module can contain a partial number of classes
1160 // that are part of the overall module definition. So if a particular class is not
1161 // found within its module specification, the search should continue to Load Attempt #2.
1162 // Note: The --patch-module entries are never searched if the boot loader's
1163 // visibility boundary is limited to only searching the append entries.
1164 if (_patch_mod_entries != nullptr && !search_append_only) {
1165 // At CDS dump time, the --patch-module entries are ignored. That means a
1166 // class is still loaded from the runtime image even if it might
1167 // appear in the _patch_mod_entries. The runtime shared class visibility
1168 // check will determine if a shared class is visible based on the runtime
1169 // environment, including the runtime --patch-module setting.
1170 //
1171 // DynamicDumpSharedSpaces requires UseSharedSpaces to be enabled. Since --patch-module
1172 // is not supported with UseSharedSpaces, it is not supported with DynamicDumpSharedSpaces.
1173 assert(!DynamicDumpSharedSpaces, "sanity");
1174 if (!DumpSharedSpaces) {
1175 stream = search_module_entries(THREAD, _patch_mod_entries, class_name, file_name);
1176 }
1177 }
1178
1179 // Load Attempt #2: [jimage | exploded build]
1180 if (!search_append_only && (nullptr == stream)) {
1181 if (has_jrt_entry()) {
1182 e = _jrt_entry;
1183 stream = _jrt_entry->open_stream(THREAD, file_name);
1184 } else {
1185 // Exploded build - attempt to locate class in its defining module's location.
1186 assert(_exploded_entries != nullptr, "No exploded build entries present");
1187 stream = search_module_entries(THREAD, _exploded_entries, class_name, file_name);
1188 }
1189 }
1190
1191 // Load Attempt #3: [-Xbootclasspath/a]; [jvmti appended entries]
1192 if (search_append_only && (nullptr == stream)) {
1193 // For the boot loader append path search, the starting classpath_index
1194 // for the appended piece is always 1 to account for either the
1195 // _jrt_entry or the _exploded_entries.
1196 assert(classpath_index == 0, "The classpath_index has been incremented incorrectly");
1197 classpath_index = 1;
1198
1199 e = first_append_entry();
1200 while (e != nullptr) {
1201 stream = e->open_stream(THREAD, file_name);
1202 if (nullptr != stream) {
1203 break;
1204 }
1205 e = e->next();
1206 ++classpath_index;
1207 }
1208 }
1209
1210 if (nullptr == stream) {
1211 return nullptr;
1212 }
1213
1214 stream->set_verify(ClassLoaderExt::should_verify(classpath_index));
1215
1216 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
1217 Handle protection_domain;
1218 ClassLoadInfo cl_info(protection_domain);
1219
1220 InstanceKlass* result = KlassFactory::create_from_stream(stream,
1221 name,
1222 loader_data,
1223 cl_info,
1224 CHECK_NULL);
1225 result->set_classpath_index(classpath_index);
1226 return result;
1227 }
1228
1229 #if INCLUDE_CDS
1230 char* ClassLoader::skip_uri_protocol(char* source) {
1231 if (strncmp(source, "file:", 5) == 0) {
1232 // file: protocol path could start with file:/ or file:///
1233 // locate the char after all the forward slashes
1234 int offset = 5;
1235 while (*(source + offset) == '/') {
1236 offset++;
1237 }
1238 source += offset;
1239 // for non-windows platforms, move back one char as the path begins with a '/'
1240 #ifndef _WINDOWS
1241 source -= 1;
1242 #endif
1243 } else if (strncmp(source, "jrt:/", 5) == 0) {
1244 source += 5;
1245 }
1246 return source;
1247 }
1248
1249 // Record the shared classpath index and loader type for classes loaded
1250 // by the builtin loaders at dump time.
1251 void ClassLoader::record_result(JavaThread* current, InstanceKlass* ik,
1252 const ClassFileStream* stream, bool redefined) {
1253 Arguments::assert_is_dumping_archive();
1254 assert(stream != nullptr, "sanity");
1255
1256 if (ik->is_hidden()) {
1257 // We do not archive hidden classes.
1258 return;
1259 }
1260
1261 oop loader = ik->class_loader();
1262 char* src = (char*)stream->source();
1263 if (src == nullptr) {
1264 if (loader == nullptr) {
1265 // JFR classes
1266 ik->set_shared_classpath_index(0);
1267 ik->set_shared_class_loader_type(ClassLoader::BOOT_LOADER);
1268 }
1269 return;
1270 }
1271
1272 assert(has_jrt_entry(), "CDS dumping does not support exploded JDK build");
1273
1274 ResourceMark rm(current);
1275 int classpath_index = -1;
1276 PackageEntry* pkg_entry = ik->package();
1277
1278 if (FileMapInfo::get_number_of_shared_paths() > 0) {
1279 // Save the path from the file: protocol or the module name from the jrt: protocol
1280 // if no protocol prefix is found, path is the same as stream->source(). This path
1281 // must be valid since the class has been successfully parsed.
1282 char* path = skip_uri_protocol(src);
1283 assert(path != nullptr, "sanity");
1284 for (int i = 0; i < FileMapInfo::get_number_of_shared_paths(); i++) {
1285 SharedClassPathEntry* ent = FileMapInfo::shared_path(i);
1286 // A shared path has been validated during its creation in ClassLoader::create_class_path_entry(),
1287 // it must be valid here.
1288 assert(ent->name() != nullptr, "sanity");
1289 // If the path (from the class stream source) is the same as the shared
1290 // class or module path, then we have a match.
1291 // src may come from the App/Platform class loaders, which would canonicalize
1292 // the file name. We cannot use strcmp to check for equality against ent->name().
1293 // We must use os::same_files (which is faster than canonicalizing ent->name()).
1294 if (os::same_files(ent->name(), path)) {
1295 // null pkg_entry and pkg_entry in an unnamed module implies the class
1296 // is from the -cp or boot loader append path which consists of -Xbootclasspath/a
1297 // and jvmti appended entries.
1298 if ((pkg_entry == nullptr) || (pkg_entry->in_unnamed_module())) {
1299 // Ensure the index is within the -cp range before assigning
1300 // to the classpath_index.
1301 if (SystemDictionary::is_system_class_loader(loader) &&
1302 (i >= ClassLoaderExt::app_class_paths_start_index()) &&
1303 (i < ClassLoaderExt::app_module_paths_start_index())) {
1304 classpath_index = i;
1305 break;
1306 } else {
1307 if ((i >= 1) &&
1308 (i < ClassLoaderExt::app_class_paths_start_index())) {
1309 // The class must be from boot loader append path which consists of
1310 // -Xbootclasspath/a and jvmti appended entries.
1311 assert(loader == nullptr, "sanity");
1312 classpath_index = i;
1313 break;
1314 }
1315 }
1316 } else {
1317 // A class from a named module from the --module-path. Ensure the index is
1318 // within the --module-path range before assigning to the classpath_index.
1319 if ((pkg_entry != nullptr) && !(pkg_entry->in_unnamed_module()) && (i > 0)) {
1320 if (i >= ClassLoaderExt::app_module_paths_start_index() &&
1321 i < FileMapInfo::get_number_of_shared_paths()) {
1322 classpath_index = i;
1323 break;
1324 }
1325 }
1326 }
1327 }
1328 // for index 0 and the stream->source() is the modules image or has the jrt: protocol.
1329 // The class must be from the runtime modules image.
1330 if (i == 0 && (stream->from_boot_loader_modules_image() || string_starts_with(src, "jrt:"))) {
1331 classpath_index = i;
1332 break;
1333 }
1334 }
1335
1336 // No path entry found for this class: most likely a shared class loaded by the
1337 // user defined classloader.
1338 if (classpath_index < 0 && !SystemDictionaryShared::is_builtin_loader(ik->class_loader_data())) {
1339 assert(ik->shared_classpath_index() < 0, "not assigned yet");
1340 ik->set_shared_classpath_index(UNREGISTERED_INDEX);
1341 SystemDictionaryShared::set_shared_class_misc_info(ik, (ClassFileStream*)stream);
1342 return;
1343 }
1344 } else {
1345 // The shared path table is set up after module system initialization.
1346 // The path table contains no entry before that. Any classes loaded prior
1347 // to the setup of the shared path table must be from the modules image.
1348 assert(stream->from_boot_loader_modules_image(), "stream must be loaded by boot loader from modules image");
1349 assert(FileMapInfo::get_number_of_shared_paths() == 0, "shared path table must not have been setup");
1350 classpath_index = 0;
1351 }
1352
1353 const char* const class_name = ik->name()->as_C_string();
1354 const char* const file_name = file_name_for_class_name(class_name,
1355 ik->name()->utf8_length());
1356 assert(file_name != nullptr, "invariant");
1357 ClassLoaderExt::record_result(checked_cast<s2>(classpath_index), ik, redefined);
1358 }
1359 #endif // INCLUDE_CDS
1360
1361 // Initialize the class loader's access to methods in libzip. Parse and
1362 // process the boot classpath into a list ClassPathEntry objects. Once
1363 // this list has been created, it must not change order (see class PackageInfo)
1364 // it can be appended to and is by jvmti.
1365
1366 void ClassLoader::initialize(TRAPS) {
1367 if (UsePerfData) {
1368 // jvmstat performance counters
1369 NEWPERFTICKCOUNTER(_perf_accumulated_time, SUN_CLS, "time");
1370 NEWPERFTICKCOUNTER(_perf_class_init_time, SUN_CLS, "classInitTime");
1371 NEWPERFTICKCOUNTER(_perf_class_init_selftime, SUN_CLS, "classInitTime.self");
1372 NEWPERFTICKCOUNTER(_perf_class_verify_time, SUN_CLS, "classVerifyTime");
1373 NEWPERFTICKCOUNTER(_perf_class_verify_selftime, SUN_CLS, "classVerifyTime.self");
1374 NEWPERFTICKCOUNTER(_perf_class_link_time, SUN_CLS, "classLinkedTime");
1375 NEWPERFTICKCOUNTER(_perf_class_link_selftime, SUN_CLS, "classLinkedTime.self");
1376 NEWPERFEVENTCOUNTER(_perf_classes_inited, SUN_CLS, "initializedClasses");
1377 NEWPERFEVENTCOUNTER(_perf_classes_linked, SUN_CLS, "linkedClasses");
1378 NEWPERFEVENTCOUNTER(_perf_classes_verified, SUN_CLS, "verifiedClasses");
1379
1380 NEWPERFTICKCOUNTER(_perf_sys_class_lookup_time, SUN_CLS, "lookupSysClassTime");
1381 NEWPERFTICKCOUNTER(_perf_shared_classload_time, SUN_CLS, "sharedClassLoadTime");
1382 NEWPERFTICKCOUNTER(_perf_sys_classload_time, SUN_CLS, "sysClassLoadTime");
1383 NEWPERFTICKCOUNTER(_perf_app_classload_time, SUN_CLS, "appClassLoadTime");
1384 NEWPERFTICKCOUNTER(_perf_app_classload_selftime, SUN_CLS, "appClassLoadTime.self");
1385 NEWPERFEVENTCOUNTER(_perf_app_classload_count, SUN_CLS, "appClassLoadCount");
1386 NEWPERFTICKCOUNTER(_perf_define_appclasses, SUN_CLS, "defineAppClasses");
1387 NEWPERFTICKCOUNTER(_perf_define_appclass_time, SUN_CLS, "defineAppClassTime");
1388 NEWPERFTICKCOUNTER(_perf_define_appclass_selftime, SUN_CLS, "defineAppClassTime.self");
1389 NEWPERFBYTECOUNTER(_perf_app_classfile_bytes_read, SUN_CLS, "appClassBytes");
1390 NEWPERFBYTECOUNTER(_perf_sys_classfile_bytes_read, SUN_CLS, "sysClassBytes");
1391
1392 NEWPERFEVENTCOUNTER(_unsafe_defineClassCallCounter, SUN_CLS, "unsafeDefineClassCalls");
1393 }
1394
1395 // lookup java library entry points
1396 load_java_library();
1397 // jimage library entry points are loaded below, in lookup_vm_options
1398 setup_bootstrap_search_path(THREAD);
1399 }
1400
1401 char* lookup_vm_resource(JImageFile *jimage, const char *jimage_version, const char *path) {
1402 jlong size;
1403 JImageLocationRef location = (*JImageFindResource)(jimage, "java.base", jimage_version, path, &size);
1404 if (location == 0)
1405 return nullptr;
1406 char *val = NEW_C_HEAP_ARRAY(char, size+1, mtClass);
1407 (*JImageGetResource)(jimage, location, val, size);
1408 val[size] = '\0';
1409 return val;
1410 }
1411
1412 // Lookup VM options embedded in the modules jimage file
1413 char* ClassLoader::lookup_vm_options() {
1414 jint error;
1415 char modules_path[JVM_MAXPATHLEN];
1416 const char* fileSep = os::file_separator();
1417
1418 // Initialize jimage library entry points
1419 load_jimage_library();
1420
1421 jio_snprintf(modules_path, JVM_MAXPATHLEN, "%s%slib%smodules", Arguments::get_java_home(), fileSep, fileSep);
1422 JImage_file =(*JImageOpen)(modules_path, &error);
1423 if (JImage_file == nullptr) {
1424 return nullptr;
1425 }
1426
1427 const char *jimage_version = get_jimage_version_string();
1428 char *options = lookup_vm_resource(JImage_file, jimage_version, "jdk/internal/vm/options");
1429 return options;
1430 }
1431
1432 bool ClassLoader::is_module_observable(const char* module_name) {
1433 assert(JImageOpen != nullptr, "jimage library should have been opened");
1434 if (JImage_file == nullptr) {
1435 struct stat st;
1436 const char *path = get_exploded_module_path(module_name, true);
1437 bool res = os::stat(path, &st) == 0;
1438 FREE_C_HEAP_ARRAY(char, path);
1439 return res;
1440 }
1441 jlong size;
1442 const char *jimage_version = get_jimage_version_string();
1443 return (*JImageFindResource)(JImage_file, module_name, jimage_version, "module-info.class", &size) != 0;
1444 }
1445
1446 #if INCLUDE_CDS
1447 void ClassLoader::initialize_shared_path(JavaThread* current) {
1448 if (Arguments::is_dumping_archive()) {
1449 ClassLoaderExt::setup_search_paths(current);
1450 }
1451 }
1452
1453 void ClassLoader::initialize_module_path(TRAPS) {
1454 if (Arguments::is_dumping_archive()) {
1455 ClassLoaderExt::setup_module_paths(THREAD);
1456 FileMapInfo::allocate_shared_path_table(CHECK);
1457 }
1458 }
1459
1460 // Helper function used by CDS code to get the number of module path
1461 // entries during shared classpath setup time.
1462 int ClassLoader::num_module_path_entries() {
1463 Arguments::assert_is_dumping_archive();
1464 int num_entries = 0;
1465 ClassPathEntry* e= ClassLoader::_module_path_entries;
1466 while (e != nullptr) {
1467 num_entries ++;
1468 e = e->next();
1469 }
1470 return num_entries;
1471 }
1472 #endif
1473
1474 jlong ClassLoader::classloader_time_ms() {
1475 return UsePerfData ?
1476 Management::ticks_to_ms(_perf_accumulated_time->get_value()) : -1;
1477 }
1478
1479 jlong ClassLoader::class_init_count() {
1480 return UsePerfData ? _perf_classes_inited->get_value() : -1;
1481 }
1482
1483 jlong ClassLoader::class_init_time_ms() {
1484 return UsePerfData ?
1485 Management::ticks_to_ms(_perf_class_init_time->get_value()) : -1;
1486 }
1487
1488 jlong ClassLoader::class_verify_time_ms() {
1489 return UsePerfData ?
1490 Management::ticks_to_ms(_perf_class_verify_time->get_value()) : -1;
1491 }
1492
1493 jlong ClassLoader::class_link_count() {
1494 return UsePerfData ? _perf_classes_linked->get_value() : -1;
1495 }
1496
1497 jlong ClassLoader::class_link_time_ms() {
1498 return UsePerfData ?
1499 Management::ticks_to_ms(_perf_class_link_time->get_value()) : -1;
1500 }
1501
1502 int ClassLoader::compute_Object_vtable() {
1503 // hardwired for JDK1.2 -- would need to duplicate class file parsing
1504 // code to determine actual value from file
1505 // Would be value '11' if finals were in vtable
1506 int JDK_1_2_Object_vtable_size = 5;
1507 return JDK_1_2_Object_vtable_size * vtableEntry::size();
1508 }
1509
1510
1511 void classLoader_init1() {
1512 EXCEPTION_MARK;
1513 ClassLoader::initialize(THREAD);
1514 if (HAS_PENDING_EXCEPTION) {
1515 vm_exit_during_initialization("ClassLoader::initialize() failed unexpectedly");
1516 }
1517 }
1518
1519 // Complete the ClassPathEntry setup for the boot loader
1520 void ClassLoader::classLoader_init2(JavaThread* current) {
1521 // Setup the list of module/path pairs for --patch-module processing
1522 // This must be done after the SymbolTable is created in order
1523 // to use fast_compare on module names instead of a string compare.
1524 if (Arguments::get_patch_mod_prefix() != nullptr) {
1525 setup_patch_mod_entries();
1526 }
1527
1528 // Create the ModuleEntry for java.base (must occur after setup_patch_mod_entries
1529 // to successfully determine if java.base has been patched)
1530 create_javabase();
1531
1532 // Setup the initial java.base/path pair for the exploded build entries.
1533 // As more modules are defined during module system initialization, more
1534 // entries will be added to the exploded build array.
1535 if (!has_jrt_entry()) {
1536 assert(!DumpSharedSpaces, "DumpSharedSpaces not supported with exploded module builds");
1537 assert(!DynamicDumpSharedSpaces, "DynamicDumpSharedSpaces not supported with exploded module builds");
1538 assert(!UseSharedSpaces, "UsedSharedSpaces not supported with exploded module builds");
1539 // Set up the boot loader's _exploded_entries list. Note that this gets
1540 // done before loading any classes, by the same thread that will
1541 // subsequently do the first class load. So, no lock is needed for this.
1542 assert(_exploded_entries == nullptr, "Should only get initialized once");
1543 _exploded_entries = new (mtModule)
1544 GrowableArray<ModuleClassPathList*>(EXPLODED_ENTRY_SIZE, mtModule);
1545 add_to_exploded_build_list(current, vmSymbols::java_base());
1546 }
1547 }
1548
1549 char* ClassLoader::get_canonical_path(const char* orig, Thread* thread) {
1550 assert(orig != nullptr, "bad arguments");
1551 // caller needs to allocate ResourceMark for the following output buffer
1552 char* canonical_path = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, JVM_MAXPATHLEN);
1553 ResourceMark rm(thread);
1554 // os::native_path writes into orig_copy
1555 char* orig_copy = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, strlen(orig)+1);
1556 strcpy(orig_copy, orig);
1557 if ((CanonicalizeEntry)(os::native_path(orig_copy), canonical_path, JVM_MAXPATHLEN) < 0) {
1558 return nullptr;
1559 }
1560 return canonical_path;
1561 }
1562
1563 void ClassLoader::create_javabase() {
1564 JavaThread* current = JavaThread::current();
1565
1566 // Create java.base's module entry for the boot
1567 // class loader prior to loading j.l.Object.
1568 ClassLoaderData* null_cld = ClassLoaderData::the_null_class_loader_data();
1569
1570 // Get module entry table
1571 ModuleEntryTable* null_cld_modules = null_cld->modules();
1572 if (null_cld_modules == nullptr) {
1573 vm_exit_during_initialization("No ModuleEntryTable for the boot class loader");
1574 }
1575
1576 {
1577 MutexLocker ml(current, Module_lock);
1578 if (ModuleEntryTable::javabase_moduleEntry() == nullptr) { // may have been inited by CDS.
1579 ModuleEntry* jb_module = null_cld_modules->locked_create_entry(Handle(),
1580 false, vmSymbols::java_base(), nullptr, nullptr, null_cld);
1581 if (jb_module == nullptr) {
1582 vm_exit_during_initialization("Unable to create ModuleEntry for " JAVA_BASE_NAME);
1583 }
1584 ModuleEntryTable::set_javabase_moduleEntry(jb_module);
1585 }
1586 }
1587 }
1588
1589 // Please keep following two functions at end of this file. With them placed at top or in middle of the file,
1590 // they could get inlined by aggressive compiler, an unknown trick, see bug 6966589.
1591 void PerfClassTraceTime::initialize() {
1592 if (!UsePerfData) return;
1593
1594 if (_eventp != nullptr) {
1595 // increment the event counter
1596 _eventp->inc();
1597 }
1598
1599 // stop the current active thread-local timer to measure inclusive time
1600 _prev_active_event = -1;
1601 for (int i=0; i < EVENT_TYPE_COUNT; i++) {
1602 if (_timers[i].is_active()) {
1603 assert(_prev_active_event == -1, "should have only one active timer");
1604 _prev_active_event = i;
1605 _timers[i].stop();
1606 }
1607 }
1608
1609 if (_recursion_counters == nullptr || (_recursion_counters[_event_type])++ == 0) {
1610 // start the inclusive timer if not recursively called
1611 _t.start();
1612 }
1613
1614 // start thread-local timer of the given event type
1615 if (!_timers[_event_type].is_active()) {
1616 _timers[_event_type].start();
1617 }
1618 }
1619
1620 PerfClassTraceTime::~PerfClassTraceTime() {
1621 if (!UsePerfData) return;
1622
1623 // stop the thread-local timer as the event completes
1624 // and resume the thread-local timer of the event next on the stack
1625 _timers[_event_type].stop();
1626 jlong selftime = _timers[_event_type].ticks();
1627
1628 if (_prev_active_event >= 0) {
1629 _timers[_prev_active_event].start();
1630 }
1631
1632 if (_recursion_counters != nullptr && --(_recursion_counters[_event_type]) > 0) return;
1633
1634 // increment the counters only on the leaf call
1635 _t.stop();
1636 _timep->inc(_t.ticks());
1637 if (_selftimep != nullptr) {
1638 _selftimep->inc(selftime);
1639 }
1640 // add all class loading related event selftime to the accumulated time counter
1641 ClassLoader::perf_accumulated_time()->inc(selftime);
1642
1643 // reset the timer
1644 _timers[_event_type].reset();
1645 }