1 /*
   2  * Copyright (c) 1997, 2019, 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 "jvm.h"
  27 #include "jimage.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/javaClasses.hpp"
  33 #include "classfile/moduleEntry.hpp"
  34 #include "classfile/modules.hpp"
  35 #include "classfile/packageEntry.hpp"
  36 #include "classfile/klassFactory.hpp"
  37 #include "classfile/symbolTable.hpp"
  38 #include "classfile/systemDictionary.hpp"
  39 #include "classfile/systemDictionaryShared.hpp"
  40 #include "classfile/vmSymbols.hpp"
  41 #include "compiler/compileBroker.hpp"
  42 #include "interpreter/bytecodeStream.hpp"
  43 #include "interpreter/oopMapCache.hpp"
  44 #include "logging/log.hpp"
  45 #include "logging/logStream.hpp"
  46 #include "logging/logTag.hpp"
  47 #include "memory/allocation.inline.hpp"
  48 #include "memory/filemap.hpp"
  49 #include "memory/oopFactory.hpp"
  50 #include "memory/resourceArea.hpp"
  51 #include "memory/universe.hpp"
  52 #include "oops/instanceKlass.hpp"
  53 #include "oops/instanceRefKlass.hpp"
  54 #include "oops/method.inline.hpp"
  55 #include "oops/objArrayOop.inline.hpp"
  56 #include "oops/oop.inline.hpp"
  57 #include "oops/symbol.hpp"
  58 #include "prims/jvm_misc.hpp"
  59 #include "runtime/arguments.hpp"
  60 #include "runtime/compilationPolicy.hpp"
  61 #include "runtime/handles.inline.hpp"
  62 #include "runtime/init.hpp"
  63 #include "runtime/interfaceSupport.inline.hpp"
  64 #include "runtime/java.hpp"
  65 #include "runtime/javaCalls.hpp"
  66 #include "runtime/os.inline.hpp"
  67 #include "runtime/threadCritical.hpp"
  68 #include "runtime/timer.hpp"
  69 #include "runtime/vm_version.hpp"
  70 #include "services/management.hpp"
  71 #include "services/threadService.hpp"
  72 #include "utilities/classpathStream.hpp"
  73 #include "utilities/events.hpp"
  74 #include "utilities/hashtable.inline.hpp"
  75 #include "utilities/macros.hpp"
  76 
  77 // Entry points in zip.dll for loading zip/jar file entries
  78 
  79 typedef void * * (*ZipOpen_t)(const char *name, char **pmsg);
  80 typedef void (*ZipClose_t)(jzfile *zip);
  81 typedef jzentry* (*FindEntry_t)(jzfile *zip, const char *name, jint *sizeP, jint *nameLen);
  82 typedef jboolean (*ReadEntry_t)(jzfile *zip, jzentry *entry, unsigned char *buf, char *namebuf);
  83 typedef jzentry* (*GetNextEntry_t)(jzfile *zip, jint n);
  84 typedef jboolean (*ZipInflateFully_t)(void *inBuf, jlong inLen, void *outBuf, jlong outLen, char **pmsg);
  85 typedef jint     (*Crc32_t)(jint crc, const jbyte *buf, jint len);
  86 
  87 static ZipOpen_t         ZipOpen            = NULL;
  88 static ZipClose_t        ZipClose           = NULL;
  89 static FindEntry_t       FindEntry          = NULL;
  90 static ReadEntry_t       ReadEntry          = NULL;
  91 static GetNextEntry_t    GetNextEntry       = NULL;
  92 static canonicalize_fn_t CanonicalizeEntry  = NULL;
  93 static ZipInflateFully_t ZipInflateFully    = NULL;
  94 static Crc32_t           Crc32              = NULL;
  95 
  96 // Entry points for jimage.dll for loading jimage file entries
  97 
  98 static JImageOpen_t                    JImageOpen             = NULL;
  99 static JImageClose_t                   JImageClose            = NULL;
 100 static JImagePackageToModule_t         JImagePackageToModule  = NULL;
 101 static JImageFindResource_t            JImageFindResource     = NULL;
 102 static JImageGetResource_t             JImageGetResource      = NULL;
 103 static JImageResourceIterator_t        JImageResourceIterator = NULL;
 104 
 105 // Globals
 106 
 107 PerfCounter*    ClassLoader::_perf_accumulated_time = NULL;
 108 PerfCounter*    ClassLoader::_perf_classes_inited = NULL;
 109 PerfCounter*    ClassLoader::_perf_class_init_time = NULL;
 110 PerfCounter*    ClassLoader::_perf_class_init_selftime = NULL;
 111 PerfCounter*    ClassLoader::_perf_classes_verified = NULL;
 112 PerfCounter*    ClassLoader::_perf_class_verify_time = NULL;
 113 PerfCounter*    ClassLoader::_perf_class_verify_selftime = NULL;
 114 PerfCounter*    ClassLoader::_perf_classes_linked = NULL;
 115 PerfCounter*    ClassLoader::_perf_class_link_time = NULL;
 116 PerfCounter*    ClassLoader::_perf_class_link_selftime = NULL;
 117 PerfCounter*    ClassLoader::_perf_class_parse_time = NULL;
 118 PerfCounter*    ClassLoader::_perf_class_parse_selftime = NULL;
 119 PerfCounter*    ClassLoader::_perf_sys_class_lookup_time = NULL;
 120 PerfCounter*    ClassLoader::_perf_shared_classload_time = NULL;
 121 PerfCounter*    ClassLoader::_perf_sys_classload_time = NULL;
 122 PerfCounter*    ClassLoader::_perf_app_classload_time = NULL;
 123 PerfCounter*    ClassLoader::_perf_app_classload_selftime = NULL;
 124 PerfCounter*    ClassLoader::_perf_app_classload_count = NULL;
 125 PerfCounter*    ClassLoader::_perf_define_appclasses = NULL;
 126 PerfCounter*    ClassLoader::_perf_define_appclass_time = NULL;
 127 PerfCounter*    ClassLoader::_perf_define_appclass_selftime = NULL;
 128 PerfCounter*    ClassLoader::_perf_app_classfile_bytes_read = NULL;
 129 PerfCounter*    ClassLoader::_perf_sys_classfile_bytes_read = NULL;
 130 PerfCounter*    ClassLoader::_sync_systemLoaderLockContentionRate = NULL;
 131 PerfCounter*    ClassLoader::_sync_nonSystemLoaderLockContentionRate = NULL;
 132 PerfCounter*    ClassLoader::_sync_JVMFindLoadedClassLockFreeCounter = NULL;
 133 PerfCounter*    ClassLoader::_sync_JVMDefineClassLockFreeCounter = NULL;
 134 PerfCounter*    ClassLoader::_sync_JNIDefineClassLockFreeCounter = NULL;
 135 PerfCounter*    ClassLoader::_unsafe_defineClassCallCounter = NULL;
 136 
 137 GrowableArray<ModuleClassPathList*>* ClassLoader::_patch_mod_entries = NULL;
 138 GrowableArray<ModuleClassPathList*>* ClassLoader::_exploded_entries = NULL;
 139 ClassPathEntry* ClassLoader::_jrt_entry = NULL;
 140 ClassPathEntry* ClassLoader::_first_append_entry = NULL;
 141 ClassPathEntry* ClassLoader::_last_append_entry  = NULL;
 142 #if INCLUDE_CDS
 143 ClassPathEntry* ClassLoader::_app_classpath_entries = NULL;
 144 ClassPathEntry* ClassLoader::_last_app_classpath_entry = NULL;
 145 ClassPathEntry* ClassLoader::_module_path_entries = NULL;
 146 ClassPathEntry* ClassLoader::_last_module_path_entry = NULL;
 147 #endif
 148 
 149 // helper routines
 150 bool string_starts_with(const char* str, const char* str_to_find) {
 151   size_t str_len = strlen(str);
 152   size_t str_to_find_len = strlen(str_to_find);
 153   if (str_to_find_len > str_len) {
 154     return false;
 155   }
 156   return (strncmp(str, str_to_find, str_to_find_len) == 0);
 157 }
 158 
 159 static const char* get_jimage_version_string() {
 160   static char version_string[10] = "";
 161   if (version_string[0] == '\0') {
 162     jio_snprintf(version_string, sizeof(version_string), "%d.%d",
 163                  VM_Version::vm_major_version(), VM_Version::vm_minor_version());
 164   }
 165   return (const char*)version_string;
 166 }
 167 
 168 bool ClassLoader::string_ends_with(const char* str, const char* str_to_find) {
 169   size_t str_len = strlen(str);
 170   size_t str_to_find_len = strlen(str_to_find);
 171   if (str_to_find_len > str_len) {
 172     return false;
 173   }
 174   return (strncmp(str + (str_len - str_to_find_len), str_to_find, str_to_find_len) == 0);
 175 }
 176 
 177 // Used to obtain the package name from a fully qualified class name.
 178 // It is the responsibility of the caller to establish a ResourceMark.
 179 const char* ClassLoader::package_from_name(const char* const class_name, bool* bad_class_name) {
 180   if (class_name == NULL) {
 181     if (bad_class_name != NULL) {
 182       *bad_class_name = true;
 183     }
 184     return NULL;
 185   }
 186 
 187   if (bad_class_name != NULL) {
 188     *bad_class_name = false;
 189   }
 190 
 191   const char* const last_slash = strrchr(class_name, '/');
 192   if (last_slash == NULL) {
 193     // No package name
 194     return NULL;
 195   }
 196 
 197   char* class_name_ptr = (char*) class_name;
 198   // Skip over '['s
 199   if (*class_name_ptr == '[') {
 200     do {
 201       class_name_ptr++;
 202     } while (*class_name_ptr == '[');
 203 
 204     // Fully qualified class names should not contain a 'L'.
 205     // Set bad_class_name to true to indicate that the package name
 206     // could not be obtained due to an error condition.
 207     // In this situation, is_same_class_package returns false.
 208     if (*class_name_ptr == 'L') {
 209       if (bad_class_name != NULL) {
 210         *bad_class_name = true;
 211       }
 212       return NULL;
 213     }
 214   }
 215 
 216   int length = last_slash - class_name_ptr;
 217 
 218   // A class name could have just the slash character in the name.
 219   if (length <= 0) {
 220     // No package name
 221     if (bad_class_name != NULL) {
 222       *bad_class_name = true;
 223     }
 224     return NULL;
 225   }
 226 
 227   // drop name after last slash (including slash)
 228   // Ex., "java/lang/String.class" => "java/lang"
 229   char* pkg_name = NEW_RESOURCE_ARRAY(char, length + 1);
 230   strncpy(pkg_name, class_name_ptr, length);
 231   *(pkg_name+length) = '\0';
 232 
 233   return (const char *)pkg_name;
 234 }
 235 
 236 // Given a fully qualified class name, find its defining package in the class loader's
 237 // package entry table.
 238 PackageEntry* ClassLoader::get_package_entry(const char* class_name, ClassLoaderData* loader_data, TRAPS) {
 239   ResourceMark rm(THREAD);
 240   const char *pkg_name = ClassLoader::package_from_name(class_name);
 241   if (pkg_name == NULL) {
 242     return NULL;
 243   }
 244   PackageEntryTable* pkgEntryTable = loader_data->packages();
 245   TempNewSymbol pkg_symbol = SymbolTable::new_symbol(pkg_name);
 246   return pkgEntryTable->lookup_only(pkg_symbol);
 247 }
 248 
 249 const char* ClassPathEntry::copy_path(const char* path) {
 250   char* copy = NEW_C_HEAP_ARRAY(char, strlen(path)+1, mtClass);
 251   strcpy(copy, path);
 252   return copy;
 253 }
 254 
 255 ClassFileStream* ClassPathDirEntry::open_stream(const char* name, TRAPS) {
 256   // construct full path name
 257   assert((_dir != NULL) && (name != NULL), "sanity");
 258   size_t path_len = strlen(_dir) + strlen(name) + strlen(os::file_separator()) + 1;
 259   char* path = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, path_len);
 260   int len = jio_snprintf(path, path_len, "%s%s%s", _dir, os::file_separator(), name);
 261   assert(len == (int)(path_len - 1), "sanity");
 262   // check if file exists
 263   struct stat st;
 264   if (os::stat(path, &st) == 0) {
 265     // found file, open it
 266     int file_handle = os::open(path, 0, 0);
 267     if (file_handle != -1) {
 268       // read contents into resource array
 269       u1* buffer = NEW_RESOURCE_ARRAY(u1, st.st_size);
 270       size_t num_read = os::read(file_handle, (char*) buffer, st.st_size);
 271       // close file
 272       os::close(file_handle);
 273       // construct ClassFileStream
 274       if (num_read == (size_t)st.st_size) {
 275         if (UsePerfData) {
 276           ClassLoader::perf_sys_classfile_bytes_read()->inc(num_read);
 277         }
 278         FREE_RESOURCE_ARRAY(char, path, path_len);
 279         // Resource allocated
 280         return new ClassFileStream(buffer,
 281                                    st.st_size,
 282                                    _dir,
 283                                    ClassFileStream::verify);
 284       }
 285     }
 286   }
 287   FREE_RESOURCE_ARRAY(char, path, path_len);
 288   return NULL;
 289 }
 290 
 291 ClassPathZipEntry::ClassPathZipEntry(jzfile* zip, const char* zip_name,
 292                                      bool is_boot_append, bool from_class_path_attr) : ClassPathEntry() {
 293   _zip = zip;
 294   _zip_name = copy_path(zip_name);
 295   _from_class_path_attr = from_class_path_attr;
 296 }
 297 
 298 ClassPathZipEntry::~ClassPathZipEntry() {
 299   if (ZipClose != NULL) {
 300     (*ZipClose)(_zip);
 301   }
 302   FREE_C_HEAP_ARRAY(char, _zip_name);
 303 }
 304 
 305 u1* ClassPathZipEntry::open_entry(const char* name, jint* filesize, bool nul_terminate, TRAPS) {
 306     // enable call to C land
 307   JavaThread* thread = JavaThread::current();
 308   ThreadToNativeFromVM ttn(thread);
 309   // check whether zip archive contains name
 310   jint name_len;
 311   jzentry* entry = (*FindEntry)(_zip, name, filesize, &name_len);
 312   if (entry == NULL) return NULL;
 313   u1* buffer;
 314   char name_buf[128];
 315   char* filename;
 316   if (name_len < 128) {
 317     filename = name_buf;
 318   } else {
 319     filename = NEW_RESOURCE_ARRAY(char, name_len + 1);
 320   }
 321 
 322   // read contents into resource array
 323   int size = (*filesize) + ((nul_terminate) ? 1 : 0);
 324   buffer = NEW_RESOURCE_ARRAY(u1, size);
 325   if (!(*ReadEntry)(_zip, entry, buffer, filename)) return NULL;
 326 
 327   // return result
 328   if (nul_terminate) {
 329     buffer[*filesize] = 0;
 330   }
 331   return buffer;
 332 }
 333 
 334 ClassFileStream* ClassPathZipEntry::open_stream(const char* name, TRAPS) {
 335   jint filesize;
 336   u1* buffer = open_entry(name, &filesize, false, CHECK_NULL);
 337   if (buffer == NULL) {
 338     return NULL;
 339   }
 340   if (UsePerfData) {
 341     ClassLoader::perf_sys_classfile_bytes_read()->inc(filesize);
 342   }
 343   // Resource allocated
 344   return new ClassFileStream(buffer,
 345                              filesize,
 346                              _zip_name,
 347                              ClassFileStream::verify);
 348 }
 349 
 350 // invoke function for each entry in the zip file
 351 void ClassPathZipEntry::contents_do(void f(const char* name, void* context), void* context) {
 352   JavaThread* thread = JavaThread::current();
 353   HandleMark  handle_mark(thread);
 354   ThreadToNativeFromVM ttn(thread);
 355   for (int n = 0; ; n++) {
 356     jzentry * ze = ((*GetNextEntry)(_zip, n));
 357     if (ze == NULL) break;
 358     (*f)(ze->name, context);
 359   }
 360 }
 361 
 362 DEBUG_ONLY(ClassPathImageEntry* ClassPathImageEntry::_singleton = NULL;)
 363 
 364 void ClassPathImageEntry::close_jimage() {
 365   if (_jimage != NULL) {
 366     (*JImageClose)(_jimage);
 367     _jimage = NULL;
 368   }
 369 }
 370 
 371 ClassPathImageEntry::ClassPathImageEntry(JImageFile* jimage, const char* name) :
 372   ClassPathEntry(),
 373   _jimage(jimage) {
 374   guarantee(jimage != NULL, "jimage file is null");
 375   guarantee(name != NULL, "jimage file name is null");
 376   assert(_singleton == NULL, "VM supports only one jimage");
 377   DEBUG_ONLY(_singleton = this);
 378   size_t len = strlen(name) + 1;
 379   _name = copy_path(name);
 380 }
 381 
 382 ClassPathImageEntry::~ClassPathImageEntry() {
 383   assert(_singleton == this, "must be");
 384   DEBUG_ONLY(_singleton = NULL);
 385 
 386   FREE_C_HEAP_ARRAY(const char, _name);
 387 
 388   if (_jimage != NULL) {
 389     (*JImageClose)(_jimage);
 390     _jimage = NULL;
 391   }
 392 }
 393 
 394 ClassFileStream* ClassPathImageEntry::open_stream(const char* name, TRAPS) {
 395   return open_stream_for_loader(name, ClassLoaderData::the_null_class_loader_data(), THREAD);
 396 }
 397 
 398 // For a class in a named module, look it up in the jimage file using this syntax:
 399 //    /<module-name>/<package-name>/<base-class>
 400 //
 401 // Assumptions:
 402 //     1. There are no unnamed modules in the jimage file.
 403 //     2. A package is in at most one module in the jimage file.
 404 //
 405 ClassFileStream* ClassPathImageEntry::open_stream_for_loader(const char* name, ClassLoaderData* loader_data, TRAPS) {
 406   jlong size;
 407   JImageLocationRef location = (*JImageFindResource)(_jimage, "", get_jimage_version_string(), name, &size);
 408 
 409   if (location == 0) {
 410     ResourceMark rm;
 411     const char* pkg_name = ClassLoader::package_from_name(name);
 412 
 413     if (pkg_name != NULL) {
 414       if (!Universe::is_module_initialized()) {
 415         location = (*JImageFindResource)(_jimage, JAVA_BASE_NAME, get_jimage_version_string(), name, &size);
 416       } else {
 417         PackageEntry* package_entry = ClassLoader::get_package_entry(name, loader_data, CHECK_NULL);
 418         if (package_entry != NULL) {
 419           ResourceMark rm;
 420           // Get the module name
 421           ModuleEntry* module = package_entry->module();
 422           assert(module != NULL, "Boot classLoader package missing module");
 423           assert(module->is_named(), "Boot classLoader package is in unnamed module");
 424           const char* module_name = module->name()->as_C_string();
 425           if (module_name != NULL) {
 426             location = (*JImageFindResource)(_jimage, module_name, get_jimage_version_string(), name, &size);
 427           }
 428         }
 429       }
 430     }
 431   }
 432   if (location != 0) {
 433     if (UsePerfData) {
 434       ClassLoader::perf_sys_classfile_bytes_read()->inc(size);
 435     }
 436     char* data = NEW_RESOURCE_ARRAY(char, size);
 437     (*JImageGetResource)(_jimage, location, data, size);
 438     // Resource allocated
 439     assert(this == (ClassPathImageEntry*)ClassLoader::get_jrt_entry(), "must be");
 440     return new ClassFileStream((u1*)data,
 441                                (int)size,
 442                                _name,
 443                                ClassFileStream::verify,
 444                                true); // from_boot_loader_modules_image
 445   }
 446 
 447   return NULL;
 448 }
 449 
 450 JImageLocationRef ClassLoader::jimage_find_resource(JImageFile* jf,
 451                                                     const char* module_name,
 452                                                     const char* file_name,
 453                                                     jlong &size) {
 454   return ((*JImageFindResource)(jf, module_name, get_jimage_version_string(), file_name, &size));
 455 }
 456 
 457 bool ClassPathImageEntry::is_modules_image() const {
 458   assert(this == _singleton, "VM supports a single jimage");
 459   assert(this == (ClassPathImageEntry*)ClassLoader::get_jrt_entry(), "must be used for jrt entry");
 460   return true;
 461 }
 462 
 463 #if INCLUDE_CDS
 464 void ClassLoader::exit_with_path_failure(const char* error, const char* message) {
 465   Arguments::assert_is_dumping_archive();
 466   tty->print_cr("Hint: enable -Xlog:class+path=info to diagnose the failure");
 467   vm_exit_during_initialization(error, message);
 468 }
 469 #endif
 470 
 471 ModuleClassPathList::ModuleClassPathList(Symbol* module_name) {
 472   _module_name = module_name;
 473   _module_first_entry = NULL;
 474   _module_last_entry = NULL;
 475 }
 476 
 477 ModuleClassPathList::~ModuleClassPathList() {
 478   // Clean out each ClassPathEntry on list
 479   ClassPathEntry* e = _module_first_entry;
 480   while (e != NULL) {
 481     ClassPathEntry* next_entry = e->next();
 482     delete e;
 483     e = next_entry;
 484   }
 485 }
 486 
 487 void ModuleClassPathList::add_to_list(ClassPathEntry* new_entry) {
 488   if (new_entry != NULL) {
 489     if (_module_last_entry == NULL) {
 490       _module_first_entry = _module_last_entry = new_entry;
 491     } else {
 492       _module_last_entry->set_next(new_entry);
 493       _module_last_entry = new_entry;
 494     }
 495   }
 496 }
 497 
 498 void ClassLoader::trace_class_path(const char* msg, const char* name) {
 499   LogTarget(Info, class, path) lt;
 500   if (lt.is_enabled()) {
 501     LogStream ls(lt);
 502     if (msg) {
 503       ls.print("%s", msg);
 504     }
 505     if (name) {
 506       if (strlen(name) < 256) {
 507         ls.print("%s", name);
 508       } else {
 509         // For very long paths, we need to print each character separately,
 510         // as print_cr() has a length limit
 511         while (name[0] != '\0') {
 512           ls.print("%c", name[0]);
 513           name++;
 514         }
 515       }
 516     }
 517     ls.cr();
 518   }
 519 }
 520 
 521 void ClassLoader::setup_bootstrap_search_path() {
 522   const char* sys_class_path = Arguments::get_sysclasspath();
 523   assert(sys_class_path != NULL, "System boot class path must not be NULL");
 524   if (PrintSharedArchiveAndExit) {
 525     // Don't print sys_class_path - this is the bootcp of this current VM process, not necessarily
 526     // the same as the bootcp of the shared archive.
 527   } else {
 528     trace_class_path("bootstrap loader class path=", sys_class_path);
 529   }
 530   setup_boot_search_path(sys_class_path);
 531 }
 532 
 533 #if INCLUDE_CDS
 534 void ClassLoader::setup_app_search_path(const char *class_path) {
 535   Arguments::assert_is_dumping_archive();
 536 
 537   ResourceMark rm;
 538   ClasspathStream cp_stream(class_path);
 539 
 540   while (cp_stream.has_next()) {
 541     const char* path = cp_stream.get_next();
 542     update_class_path_entry_list(path, false, false, false);
 543   }
 544 }
 545 
 546 void ClassLoader::add_to_module_path_entries(const char* path,
 547                                              ClassPathEntry* entry) {
 548   assert(entry != NULL, "ClassPathEntry should not be NULL");
 549   Arguments::assert_is_dumping_archive();
 550 
 551   // The entry does not exist, add to the list
 552   if (_module_path_entries == NULL) {
 553     assert(_last_module_path_entry == NULL, "Sanity");
 554     _module_path_entries = _last_module_path_entry = entry;
 555   } else {
 556     _last_module_path_entry->set_next(entry);
 557     _last_module_path_entry = entry;
 558   }
 559 }
 560 
 561 // Add a module path to the _module_path_entries list.
 562 void ClassLoader::update_module_path_entry_list(const char *path, TRAPS) {
 563   Arguments::assert_is_dumping_archive();
 564   struct stat st;
 565   if (os::stat(path, &st) != 0) {
 566     tty->print_cr("os::stat error %d (%s). CDS dump aborted (path was \"%s\").",
 567       errno, os::errno_name(errno), path);
 568     vm_exit_during_initialization();
 569   }
 570   // File or directory found
 571   ClassPathEntry* new_entry = NULL;
 572   new_entry = create_class_path_entry(path, &st, true /* throw_exception */,
 573                                       false /*is_boot_append */, false /* from_class_path_attr */, CHECK);
 574   if (new_entry == NULL) {
 575     return;
 576   }
 577 
 578   add_to_module_path_entries(path, new_entry);
 579   return;
 580 }
 581 
 582 void ClassLoader::setup_module_search_path(const char* path, TRAPS) {
 583   update_module_path_entry_list(path, THREAD);
 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   Thread* THREAD = Thread::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 (ResourceObj::C_HEAP, mtModule) GrowableArray<ModuleClassPathList*>(num_of_entries, true);
 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 != NULL, "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(THREAD);
 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(path, &st, false, false, false, CHECK);
 621         // If the path specification is valid, enter it into this module's list
 622         if (new_entry != NULL) {
 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() != NULL) {
 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 != NULL && _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_boot_search_path(const char *class_path) {
 653   EXCEPTION_MARK;
 654   ResourceMark rm(THREAD);
 655   ClasspathStream cp_stream(class_path);
 656   bool set_base_piece = true;
 657 
 658 #if INCLUDE_CDS
 659   if (Arguments::is_dumping_archive()) {
 660     if (!Arguments::has_jimage()) {
 661       vm_exit_during_initialization("CDS is not supported in exploded JDK build", NULL);
 662     }
 663   }
 664 #endif
 665 
 666   while (cp_stream.has_next()) {
 667     const char* path = cp_stream.get_next();
 668 
 669     if (set_base_piece) {
 670       // The first time through the bootstrap_search setup, it must be determined
 671       // what the base or core piece of the boot loader search is.  Either a java runtime
 672       // image is present or this is an exploded module build situation.
 673       assert(string_ends_with(path, MODULES_IMAGE_NAME) || string_ends_with(path, JAVA_BASE_NAME),
 674              "Incorrect boot loader search path, no java runtime image or " JAVA_BASE_NAME " exploded build");
 675       struct stat st;
 676       if (os::stat(path, &st) == 0) {
 677         // Directory found
 678         ClassPathEntry* new_entry = create_class_path_entry(path, &st, false, false, false, CHECK);
 679 
 680         // Check for a jimage
 681         if (Arguments::has_jimage()) {
 682           assert(_jrt_entry == NULL, "should not setup bootstrap class search path twice");
 683           _jrt_entry = new_entry;
 684           assert(new_entry != NULL && new_entry->is_modules_image(), "No java runtime image present");
 685           assert(_jrt_entry->jimage() != NULL, "No java runtime image");
 686         }
 687       } else {
 688         // If path does not exist, exit
 689         vm_exit_during_initialization("Unable to establish the boot loader search path", path);
 690       }
 691       set_base_piece = false;
 692     } else {
 693       // Every entry on the system boot class path after the initial base piece,
 694       // which is set by os::set_boot_path(), is considered an appended entry.
 695       update_class_path_entry_list(path, false, true, false);
 696     }
 697   }
 698 }
 699 
 700 // During an exploded modules build, each module defined to the boot loader
 701 // will be added to the ClassLoader::_exploded_entries array.
 702 void ClassLoader::add_to_exploded_build_list(Symbol* module_sym, TRAPS) {
 703   assert(!ClassLoader::has_jrt_entry(), "Exploded build not applicable");
 704   assert(_exploded_entries != NULL, "_exploded_entries was not initialized");
 705 
 706   // Find the module's symbol
 707   ResourceMark rm(THREAD);
 708   const char *module_name = module_sym->as_C_string();
 709   const char *home = Arguments::get_java_home();
 710   const char file_sep = os::file_separator()[0];
 711   // 10 represents the length of "modules" + 2 file separators + \0
 712   size_t len = strlen(home) + strlen(module_name) + 10;
 713   char *path = NEW_RESOURCE_ARRAY(char, len);
 714   jio_snprintf(path, len, "%s%cmodules%c%s", home, file_sep, file_sep, module_name);
 715 
 716   struct stat st;
 717   if (os::stat(path, &st) == 0) {
 718     // Directory found
 719     ClassPathEntry* new_entry = create_class_path_entry(path, &st, false, false, false, CHECK);
 720 
 721     // If the path specification is valid, enter it into this module's list.
 722     // There is no need to check for duplicate modules in the exploded entry list,
 723     // since no two modules with the same name can be defined to the boot loader.
 724     // This is checked at module definition time in Modules::define_module.
 725     if (new_entry != NULL) {
 726       ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
 727       module_cpl->add_to_list(new_entry);
 728       {
 729         MutexLocker ml(Module_lock, THREAD);
 730         _exploded_entries->push(module_cpl);
 731       }
 732       log_info(class, load)("path: %s", path);
 733     }
 734   }
 735 }
 736 
 737 ClassPathEntry* ClassLoader::create_class_path_entry(const char *path, const struct stat* st,
 738                                                      bool throw_exception,
 739                                                      bool is_boot_append,
 740                                                      bool from_class_path_attr,
 741                                                      TRAPS) {
 742   JavaThread* thread = JavaThread::current();
 743   ClassPathEntry* new_entry = NULL;
 744   if ((st->st_mode & S_IFMT) == S_IFREG) {
 745     ResourceMark rm(thread);
 746     // Regular file, should be a zip or jimage file
 747     // Canonicalized filename
 748     char* canonical_path = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, JVM_MAXPATHLEN);
 749     if (!get_canonical_path(path, canonical_path, JVM_MAXPATHLEN)) {
 750       // This matches the classic VM
 751       if (throw_exception) {
 752         THROW_MSG_(vmSymbols::java_io_IOException(), "Bad pathname", NULL);
 753       } else {
 754         return NULL;
 755       }
 756     }
 757     jint error;
 758     JImageFile* jimage =(*JImageOpen)(canonical_path, &error);
 759     if (jimage != NULL) {
 760       new_entry = new ClassPathImageEntry(jimage, canonical_path);
 761     } else {
 762       char* error_msg = NULL;
 763       jzfile* zip;
 764       {
 765         // enable call to C land
 766         ThreadToNativeFromVM ttn(thread);
 767         HandleMark hm(thread);
 768         zip = (*ZipOpen)(canonical_path, &error_msg);
 769       }
 770       if (zip != NULL && error_msg == NULL) {
 771         new_entry = new ClassPathZipEntry(zip, path, is_boot_append, from_class_path_attr);
 772       } else {
 773         char *msg;
 774         if (error_msg == NULL) {
 775           msg = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, strlen(path) + 128); ;
 776           jio_snprintf(msg, strlen(path) + 127, "error in opening JAR file %s", path);
 777         } else {
 778           int len = (int)(strlen(path) + strlen(error_msg) + 128);
 779           msg = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, len); ;
 780           jio_snprintf(msg, len - 1, "error in opening JAR file <%s> %s", error_msg, path);
 781         }
 782         // Don't complain about bad jar files added via -Xbootclasspath/a:.
 783         if (throw_exception && is_init_completed()) {
 784           THROW_MSG_(vmSymbols::java_lang_ClassNotFoundException(), msg, NULL);
 785         } else {
 786           return NULL;
 787         }
 788       }
 789     }
 790     log_info(class, path)("opened: %s", path);
 791     log_info(class, load)("opened: %s", path);
 792   } else {
 793     // Directory
 794     new_entry = new ClassPathDirEntry(path);
 795     log_info(class, load)("path: %s", path);
 796   }
 797   return new_entry;
 798 }
 799 
 800 
 801 // Create a class path zip entry for a given path (return NULL if not found
 802 // or zip/JAR file cannot be opened)
 803 ClassPathZipEntry* ClassLoader::create_class_path_zip_entry(const char *path, bool is_boot_append) {
 804   // check for a regular file
 805   struct stat st;
 806   if (os::stat(path, &st) == 0) {
 807     if ((st.st_mode & S_IFMT) == S_IFREG) {
 808       char canonical_path[JVM_MAXPATHLEN];
 809       if (get_canonical_path(path, canonical_path, JVM_MAXPATHLEN)) {
 810         char* error_msg = NULL;
 811         jzfile* zip;
 812         {
 813           // enable call to C land
 814           JavaThread* thread = JavaThread::current();
 815           ThreadToNativeFromVM ttn(thread);
 816           HandleMark hm(thread);
 817           zip = (*ZipOpen)(canonical_path, &error_msg);
 818         }
 819         if (zip != NULL && error_msg == NULL) {
 820           // create using canonical path
 821           return new ClassPathZipEntry(zip, canonical_path, is_boot_append, false);
 822         }
 823       }
 824     }
 825   }
 826   return NULL;
 827 }
 828 
 829 // returns true if entry already on class path
 830 bool ClassLoader::contains_append_entry(const char* name) {
 831   ClassPathEntry* e = _first_append_entry;
 832   while (e != NULL) {
 833     // assume zip entries have been canonicalized
 834     if (strcmp(name, e->name()) == 0) {
 835       return true;
 836     }
 837     e = e->next();
 838   }
 839   return false;
 840 }
 841 
 842 void ClassLoader::add_to_boot_append_entries(ClassPathEntry *new_entry) {
 843   if (new_entry != NULL) {
 844     if (_last_append_entry == NULL) {
 845       assert(_first_append_entry == NULL, "boot loader's append class path entry list not empty");
 846       _first_append_entry = _last_append_entry = new_entry;
 847     } else {
 848       _last_append_entry->set_next(new_entry);
 849       _last_append_entry = new_entry;
 850     }
 851   }
 852 }
 853 
 854 // Record the path entries specified in -cp during dump time. The recorded
 855 // information will be used at runtime for loading the archived app classes.
 856 //
 857 // Note that at dump time, ClassLoader::_app_classpath_entries are NOT used for
 858 // loading app classes. Instead, the app class are loaded by the
 859 // jdk/internal/loader/ClassLoaders$AppClassLoader instance.
 860 void ClassLoader::add_to_app_classpath_entries(const char* path,
 861                                                ClassPathEntry* entry,
 862                                                bool check_for_duplicates) {
 863 #if INCLUDE_CDS
 864   assert(entry != NULL, "ClassPathEntry should not be NULL");
 865   ClassPathEntry* e = _app_classpath_entries;
 866   if (check_for_duplicates) {
 867     while (e != NULL) {
 868       if (strcmp(e->name(), entry->name()) == 0) {
 869         // entry already exists
 870         return;
 871       }
 872       e = e->next();
 873     }
 874   }
 875 
 876   // The entry does not exist, add to the list
 877   if (_app_classpath_entries == NULL) {
 878     assert(_last_app_classpath_entry == NULL, "Sanity");
 879     _app_classpath_entries = _last_app_classpath_entry = entry;
 880   } else {
 881     _last_app_classpath_entry->set_next(entry);
 882     _last_app_classpath_entry = entry;
 883   }
 884 
 885   if (entry->is_jar_file()) {
 886     ClassLoaderExt::process_jar_manifest(entry, check_for_duplicates);
 887   }
 888 #endif
 889 }
 890 
 891 // Returns true IFF the file/dir exists and the entry was successfully created.
 892 bool ClassLoader::update_class_path_entry_list(const char *path,
 893                                                bool check_for_duplicates,
 894                                                bool is_boot_append,
 895                                                bool from_class_path_attr,
 896                                                bool throw_exception) {
 897   struct stat st;
 898   if (os::stat(path, &st) == 0) {
 899     // File or directory found
 900     ClassPathEntry* new_entry = NULL;
 901     Thread* THREAD = Thread::current();
 902     new_entry = create_class_path_entry(path, &st, throw_exception, is_boot_append, from_class_path_attr, CHECK_(false));
 903     if (new_entry == NULL) {
 904       return false;
 905     }
 906 
 907     // Do not reorder the bootclasspath which would break get_system_package().
 908     // Add new entry to linked list
 909     if (is_boot_append) {
 910       add_to_boot_append_entries(new_entry);
 911     } else {
 912       add_to_app_classpath_entries(path, new_entry, check_for_duplicates);
 913     }
 914     return true;
 915   } else {
 916     return false;
 917   }
 918 }
 919 
 920 static void print_module_entry_table(const GrowableArray<ModuleClassPathList*>* const module_list) {
 921   ResourceMark rm;
 922   int num_of_entries = module_list->length();
 923   for (int i = 0; i < num_of_entries; i++) {
 924     ClassPathEntry* e;
 925     ModuleClassPathList* mpl = module_list->at(i);
 926     tty->print("%s=", mpl->module_name()->as_C_string());
 927     e = mpl->module_first_entry();
 928     while (e != NULL) {
 929       tty->print("%s", e->name());
 930       e = e->next();
 931       if (e != NULL) {
 932         tty->print("%s", os::path_separator());
 933       }
 934     }
 935     tty->print(" ;");
 936   }
 937 }
 938 
 939 void ClassLoader::print_bootclasspath() {
 940   ClassPathEntry* e;
 941   tty->print("[bootclasspath= ");
 942 
 943   // Print --patch-module module/path specifications first
 944   if (_patch_mod_entries != NULL) {
 945     print_module_entry_table(_patch_mod_entries);
 946   }
 947 
 948   // [jimage | exploded modules build]
 949   if (has_jrt_entry()) {
 950     // Print the location of the java runtime image
 951     tty->print("%s ;", _jrt_entry->name());
 952   } else {
 953     // Print exploded module build path specifications
 954     if (_exploded_entries != NULL) {
 955       print_module_entry_table(_exploded_entries);
 956     }
 957   }
 958 
 959   // appended entries
 960   e = _first_append_entry;
 961   while (e != NULL) {
 962     tty->print("%s ;", e->name());
 963     e = e->next();
 964   }
 965   tty->print_cr("]");
 966 }
 967 
 968 void ClassLoader::load_zip_library() {
 969   assert(ZipOpen == NULL, "should not load zip library twice");
 970   // First make sure native library is loaded
 971   os::native_java_library();
 972   // Load zip library
 973   char path[JVM_MAXPATHLEN];
 974   char ebuf[1024];
 975   void* handle = NULL;
 976   if (os::dll_locate_lib(path, sizeof(path), Arguments::get_dll_dir(), "zip")) {
 977     handle = os::dll_load(path, ebuf, sizeof ebuf);
 978   }
 979   if (handle == NULL) {
 980     vm_exit_during_initialization("Unable to load ZIP library", path);
 981   }
 982   // Lookup zip entry points
 983   ZipOpen      = CAST_TO_FN_PTR(ZipOpen_t, os::dll_lookup(handle, "ZIP_Open"));
 984   ZipClose     = CAST_TO_FN_PTR(ZipClose_t, os::dll_lookup(handle, "ZIP_Close"));
 985   FindEntry    = CAST_TO_FN_PTR(FindEntry_t, os::dll_lookup(handle, "ZIP_FindEntry"));
 986   ReadEntry    = CAST_TO_FN_PTR(ReadEntry_t, os::dll_lookup(handle, "ZIP_ReadEntry"));
 987   GetNextEntry = CAST_TO_FN_PTR(GetNextEntry_t, os::dll_lookup(handle, "ZIP_GetNextEntry"));
 988   ZipInflateFully = CAST_TO_FN_PTR(ZipInflateFully_t, os::dll_lookup(handle, "ZIP_InflateFully"));
 989   Crc32        = CAST_TO_FN_PTR(Crc32_t, os::dll_lookup(handle, "ZIP_CRC32"));
 990 
 991   // ZIP_Close is not exported on Windows in JDK5.0 so don't abort if ZIP_Close is NULL
 992   if (ZipOpen == NULL || FindEntry == NULL || ReadEntry == NULL ||
 993       GetNextEntry == NULL || Crc32 == NULL) {
 994     vm_exit_during_initialization("Corrupted ZIP library", path);
 995   }
 996 
 997   if (ZipInflateFully == NULL) {
 998     vm_exit_during_initialization("Corrupted ZIP library ZIP_InflateFully missing", path);
 999   }
1000 
1001   // Lookup canonicalize entry in libjava.dll
1002   void *javalib_handle = os::native_java_library();
1003   CanonicalizeEntry = CAST_TO_FN_PTR(canonicalize_fn_t, os::dll_lookup(javalib_handle, "Canonicalize"));
1004   // This lookup only works on 1.3. Do not check for non-null here
1005 }
1006 
1007 void ClassLoader::load_jimage_library() {
1008   // First make sure native library is loaded
1009   os::native_java_library();
1010   // Load jimage library
1011   char path[JVM_MAXPATHLEN];
1012   char ebuf[1024];
1013   void* handle = NULL;
1014   if (os::dll_locate_lib(path, sizeof(path), Arguments::get_dll_dir(), "jimage")) {
1015     handle = os::dll_load(path, ebuf, sizeof ebuf);
1016   }
1017   if (handle == NULL) {
1018     vm_exit_during_initialization("Unable to load jimage library", path);
1019   }
1020 
1021   // Lookup jimage entry points
1022   JImageOpen = CAST_TO_FN_PTR(JImageOpen_t, os::dll_lookup(handle, "JIMAGE_Open"));
1023   guarantee(JImageOpen != NULL, "function JIMAGE_Open not found");
1024   JImageClose = CAST_TO_FN_PTR(JImageClose_t, os::dll_lookup(handle, "JIMAGE_Close"));
1025   guarantee(JImageClose != NULL, "function JIMAGE_Close not found");
1026   JImagePackageToModule = CAST_TO_FN_PTR(JImagePackageToModule_t, os::dll_lookup(handle, "JIMAGE_PackageToModule"));
1027   guarantee(JImagePackageToModule != NULL, "function JIMAGE_PackageToModule not found");
1028   JImageFindResource = CAST_TO_FN_PTR(JImageFindResource_t, os::dll_lookup(handle, "JIMAGE_FindResource"));
1029   guarantee(JImageFindResource != NULL, "function JIMAGE_FindResource not found");
1030   JImageGetResource = CAST_TO_FN_PTR(JImageGetResource_t, os::dll_lookup(handle, "JIMAGE_GetResource"));
1031   guarantee(JImageGetResource != NULL, "function JIMAGE_GetResource not found");
1032   JImageResourceIterator = CAST_TO_FN_PTR(JImageResourceIterator_t, os::dll_lookup(handle, "JIMAGE_ResourceIterator"));
1033   guarantee(JImageResourceIterator != NULL, "function JIMAGE_ResourceIterator not found");
1034 }
1035 
1036 jboolean ClassLoader::decompress(void *in, u8 inSize, void *out, u8 outSize, char **pmsg) {
1037   return (*ZipInflateFully)(in, inSize, out, outSize, pmsg);
1038 }
1039 
1040 int ClassLoader::crc32(int crc, const char* buf, int len) {
1041   assert(Crc32 != NULL, "ZIP_CRC32 is not found");
1042   return (*Crc32)(crc, (const jbyte*)buf, len);
1043 }
1044 
1045 // Function add_package extracts the package from the fully qualified class name
1046 // and checks if the package is in the boot loader's package entry table.  If so,
1047 // then it sets the classpath_index in the package entry record.
1048 //
1049 // The classpath_index field is used to find the entry on the boot loader class
1050 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
1051 // in an unnamed module.  It is also used to indicate (for all packages whose
1052 // classes are loaded by the boot loader) that at least one of the package's
1053 // classes has been loaded.
1054 bool ClassLoader::add_package(const char *fullq_class_name, s2 classpath_index, TRAPS) {
1055   assert(fullq_class_name != NULL, "just checking");
1056 
1057   // Get package name from fully qualified class name.
1058   ResourceMark rm;
1059   const char *cp = package_from_name(fullq_class_name);
1060   if (cp != NULL) {
1061     PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();
1062     TempNewSymbol pkg_symbol = SymbolTable::new_symbol(cp);
1063     PackageEntry* pkg_entry = pkg_entry_tbl->lookup_only(pkg_symbol);
1064     if (pkg_entry != NULL) {
1065       assert(classpath_index != -1, "Unexpected classpath_index");
1066       pkg_entry->set_classpath_index(classpath_index);
1067     } else {
1068       return false;
1069     }
1070   }
1071   return true;
1072 }
1073 
1074 oop ClassLoader::get_system_package(const char* name, TRAPS) {
1075   // Look up the name in the boot loader's package entry table.
1076   if (name != NULL) {
1077     TempNewSymbol package_sym = SymbolTable::new_symbol(name);
1078     // Look for the package entry in the boot loader's package entry table.
1079     PackageEntry* package =
1080       ClassLoaderData::the_null_class_loader_data()->packages()->lookup_only(package_sym);
1081 
1082     // Return NULL if package does not exist or if no classes in that package
1083     // have been loaded.
1084     if (package != NULL && package->has_loaded_class()) {
1085       ModuleEntry* module = package->module();
1086       if (module->location() != NULL) {
1087         ResourceMark rm(THREAD);
1088         Handle ml = java_lang_String::create_from_str(
1089           module->location()->as_C_string(), THREAD);
1090         return ml();
1091       }
1092       // Return entry on boot loader class path.
1093       Handle cph = java_lang_String::create_from_str(
1094         ClassLoader::classpath_entry(package->classpath_index())->name(), THREAD);
1095       return cph();
1096     }
1097   }
1098   return NULL;
1099 }
1100 
1101 objArrayOop ClassLoader::get_system_packages(TRAPS) {
1102   ResourceMark rm(THREAD);
1103   // List of pointers to PackageEntrys that have loaded classes.
1104   GrowableArray<PackageEntry*>* loaded_class_pkgs = new GrowableArray<PackageEntry*>(50);
1105   {
1106     MutexLocker ml(Module_lock, THREAD);
1107 
1108     PackageEntryTable* pe_table =
1109       ClassLoaderData::the_null_class_loader_data()->packages();
1110 
1111     // Collect the packages that have at least one loaded class.
1112     for (int x = 0; x < pe_table->table_size(); x++) {
1113       for (PackageEntry* package_entry = pe_table->bucket(x);
1114            package_entry != NULL;
1115            package_entry = package_entry->next()) {
1116         if (package_entry->has_loaded_class()) {
1117           loaded_class_pkgs->append(package_entry);
1118         }
1119       }
1120     }
1121   }
1122 
1123 
1124   // Allocate objArray and fill with java.lang.String
1125   objArrayOop r = oopFactory::new_objArray(SystemDictionary::String_klass(),
1126                                            loaded_class_pkgs->length(), CHECK_NULL);
1127   objArrayHandle result(THREAD, r);
1128   for (int x = 0; x < loaded_class_pkgs->length(); x++) {
1129     PackageEntry* package_entry = loaded_class_pkgs->at(x);
1130     Handle str = java_lang_String::create_from_symbol(package_entry->name(), CHECK_NULL);
1131     result->obj_at_put(x, str());
1132   }
1133   return result();
1134 }
1135 
1136 // caller needs ResourceMark
1137 const char* ClassLoader::file_name_for_class_name(const char* class_name,
1138                                                   int class_name_len) {
1139   assert(class_name != NULL, "invariant");
1140   assert((int)strlen(class_name) == class_name_len, "invariant");
1141 
1142   static const char class_suffix[] = ".class";
1143   size_t class_suffix_len = sizeof(class_suffix);
1144 
1145   char* const file_name = NEW_RESOURCE_ARRAY(char,
1146                                              class_name_len +
1147                                              class_suffix_len); // includes term NULL
1148 
1149   strncpy(file_name, class_name, class_name_len);
1150   strncpy(&file_name[class_name_len], class_suffix, class_suffix_len);
1151 
1152   return file_name;
1153 }
1154 
1155 ClassPathEntry* find_first_module_cpe(ModuleEntry* mod_entry,
1156                                       const GrowableArray<ModuleClassPathList*>* const module_list) {
1157   int num_of_entries = module_list->length();
1158   const Symbol* class_module_name = mod_entry->name();
1159 
1160   // Loop through all the modules in either the patch-module or exploded entries looking for module
1161   for (int i = 0; i < num_of_entries; i++) {
1162     ModuleClassPathList* module_cpl = module_list->at(i);
1163     Symbol* module_cpl_name = module_cpl->module_name();
1164 
1165     if (module_cpl_name->fast_compare(class_module_name) == 0) {
1166       // Class' module has been located.
1167       return module_cpl->module_first_entry();
1168     }
1169   }
1170   return NULL;
1171 }
1172 
1173 
1174 // Search either the patch-module or exploded build entries for class.
1175 ClassFileStream* ClassLoader::search_module_entries(const GrowableArray<ModuleClassPathList*>* const module_list,
1176                                                     const char* const class_name,
1177                                                     const char* const file_name,
1178                                                     TRAPS) {
1179   ClassFileStream* stream = NULL;
1180 
1181   // Find the class' defining module in the boot loader's module entry table
1182   PackageEntry* pkg_entry = get_package_entry(class_name, ClassLoaderData::the_null_class_loader_data(), CHECK_NULL);
1183   ModuleEntry* mod_entry = (pkg_entry != NULL) ? pkg_entry->module() : NULL;
1184 
1185   // If the module system has not defined java.base yet, then
1186   // classes loaded are assumed to be defined to java.base.
1187   // When java.base is eventually defined by the module system,
1188   // all packages of classes that have been previously loaded
1189   // are verified in ModuleEntryTable::verify_javabase_packages().
1190   if (!Universe::is_module_initialized() &&
1191       !ModuleEntryTable::javabase_defined() &&
1192       mod_entry == NULL) {
1193     mod_entry = ModuleEntryTable::javabase_moduleEntry();
1194   }
1195 
1196   // The module must be a named module
1197   ClassPathEntry* e = NULL;
1198   if (mod_entry != NULL && mod_entry->is_named()) {
1199     if (module_list == _exploded_entries) {
1200       // The exploded build entries can be added to at any time so a lock is
1201       // needed when searching them.
1202       assert(!ClassLoader::has_jrt_entry(), "Must be exploded build");
1203       MutexLocker ml(Module_lock, THREAD);
1204       e = find_first_module_cpe(mod_entry, module_list);
1205     } else {
1206       e = find_first_module_cpe(mod_entry, module_list);
1207     }
1208   }
1209 
1210   // Try to load the class from the module's ClassPathEntry list.
1211   while (e != NULL) {
1212     stream = e->open_stream(file_name, CHECK_NULL);
1213     // No context.check is required since CDS is not supported
1214     // for an exploded modules build or if --patch-module is specified.
1215     if (NULL != stream) {
1216       return stream;
1217     }
1218     e = e->next();
1219   }
1220   // If the module was located, break out even if the class was not
1221   // located successfully from that module's ClassPathEntry list.
1222   // There will not be another valid entry for that module.
1223   return NULL;
1224 }
1225 
1226 // Called by the boot classloader to load classes
1227 InstanceKlass* ClassLoader::load_class(Symbol* name, bool search_append_only, TRAPS) {
1228   assert(name != NULL, "invariant");
1229   assert(THREAD->is_Java_thread(), "must be a JavaThread");
1230 
1231   ResourceMark rm(THREAD);
1232   HandleMark hm(THREAD);
1233 
1234   const char* const class_name = name->as_C_string();
1235 
1236   EventMark m("loading class %s", class_name);
1237 
1238   const char* const file_name = file_name_for_class_name(class_name,
1239                                                          name->utf8_length());
1240   assert(file_name != NULL, "invariant");
1241 
1242   // Lookup stream for parsing .class file
1243   ClassFileStream* stream = NULL;
1244   s2 classpath_index = 0;
1245   ClassPathEntry* e = NULL;
1246 
1247   // If search_append_only is true, boot loader visibility boundaries are
1248   // set to be _first_append_entry to the end. This includes:
1249   //   [-Xbootclasspath/a]; [jvmti appended entries]
1250   //
1251   // If search_append_only is false, boot loader visibility boundaries are
1252   // set to be the --patch-module entries plus the base piece. This includes:
1253   //   [--patch-module=<module>=<file>(<pathsep><file>)*]; [jimage | exploded module build]
1254   //
1255 
1256   // Load Attempt #1: --patch-module
1257   // Determine the class' defining module.  If it appears in the _patch_mod_entries,
1258   // attempt to load the class from those locations specific to the module.
1259   // Specifications to --patch-module can contain a partial number of classes
1260   // that are part of the overall module definition.  So if a particular class is not
1261   // found within its module specification, the search should continue to Load Attempt #2.
1262   // Note: The --patch-module entries are never searched if the boot loader's
1263   //       visibility boundary is limited to only searching the append entries.
1264   if (_patch_mod_entries != NULL && !search_append_only) {
1265     // At CDS dump time, the --patch-module entries are ignored. That means a
1266     // class is still loaded from the runtime image even if it might
1267     // appear in the _patch_mod_entries. The runtime shared class visibility
1268     // check will determine if a shared class is visible based on the runtime
1269     // environemnt, including the runtime --patch-module setting.
1270     //
1271     // DynamicDumpSharedSpaces requires UseSharedSpaces to be enabled. Since --patch-module
1272     // is not supported with UseSharedSpaces, it is not supported with DynamicDumpSharedSpaces.
1273     assert(!DynamicDumpSharedSpaces, "sanity");
1274     if (!DumpSharedSpaces) {
1275       stream = search_module_entries(_patch_mod_entries, class_name, file_name, CHECK_NULL);
1276     }
1277   }
1278 
1279   // Load Attempt #2: [jimage | exploded build]
1280   if (!search_append_only && (NULL == stream)) {
1281     if (has_jrt_entry()) {
1282       e = _jrt_entry;
1283       stream = _jrt_entry->open_stream(file_name, CHECK_NULL);
1284     } else {
1285       // Exploded build - attempt to locate class in its defining module's location.
1286       assert(_exploded_entries != NULL, "No exploded build entries present");
1287       stream = search_module_entries(_exploded_entries, class_name, file_name, CHECK_NULL);
1288     }
1289   }
1290 
1291   // Load Attempt #3: [-Xbootclasspath/a]; [jvmti appended entries]
1292   if (search_append_only && (NULL == stream)) {
1293     // For the boot loader append path search, the starting classpath_index
1294     // for the appended piece is always 1 to account for either the
1295     // _jrt_entry or the _exploded_entries.
1296     assert(classpath_index == 0, "The classpath_index has been incremented incorrectly");
1297     classpath_index = 1;
1298 
1299     e = _first_append_entry;
1300     while (e != NULL) {
1301       stream = e->open_stream(file_name, CHECK_NULL);
1302       if (NULL != stream) {
1303         break;
1304       }
1305       e = e->next();
1306       ++classpath_index;
1307     }
1308   }
1309 
1310   if (NULL == stream) {
1311     return NULL;
1312   }
1313 
1314   stream->set_verify(ClassLoaderExt::should_verify(classpath_index));
1315 
1316   ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
1317   Handle protection_domain;
1318 
1319   InstanceKlass* result = KlassFactory::create_from_stream(stream,
1320                                                            name,
1321                                                            loader_data,
1322                                                            protection_domain,
1323                                                            NULL, // unsafe_anonymous_host
1324                                                            NULL, // cp_patches
1325                                                            THREAD);
1326   if (HAS_PENDING_EXCEPTION) {
1327     if (DumpSharedSpaces) {
1328       log_error(cds)("Preload Error: Failed to load %s", class_name);
1329     }
1330     return NULL;
1331   }
1332 
1333   if (!add_package(file_name, classpath_index, THREAD)) {
1334     return NULL;
1335   }
1336 
1337   return result;
1338 }
1339 
1340 #if INCLUDE_CDS
1341 char* ClassLoader::skip_uri_protocol(char* source) {
1342   if (strncmp(source, "file:", 5) == 0) {
1343     // file: protocol path could start with file:/ or file:///
1344     // locate the char after all the forward slashes
1345     int offset = 5;
1346     while (*(source + offset) == '/') {
1347         offset++;
1348     }
1349     source += offset;
1350   // for non-windows platforms, move back one char as the path begins with a '/'
1351 #ifndef _WINDOWS
1352     source -= 1;
1353 #endif
1354   } else if (strncmp(source, "jrt:/", 5) == 0) {
1355     source += 5;
1356   }
1357   return source;
1358 }
1359 
1360 // Record the shared classpath index and loader type for classes loaded
1361 // by the builtin loaders at dump time.
1362 void ClassLoader::record_result(InstanceKlass* ik, const ClassFileStream* stream, TRAPS) {
1363   Arguments::assert_is_dumping_archive();
1364   assert(stream != NULL, "sanity");
1365 
1366   if (ik->is_unsafe_anonymous()) {
1367     // We do not archive unsafe anonymous classes.
1368     return;
1369   }
1370 
1371   oop loader = ik->class_loader();
1372   char* src = (char*)stream->source();
1373   if (src == NULL) {
1374     if (loader == NULL) {
1375       // JFR classes
1376       ik->set_shared_classpath_index(0);
1377       ik->set_class_loader_type(ClassLoader::BOOT_LOADER);
1378     }
1379     return;
1380   }
1381 
1382   assert(has_jrt_entry(), "CDS dumping does not support exploded JDK build");
1383 
1384   ResourceMark rm(THREAD);
1385   int classpath_index = -1;
1386   PackageEntry* pkg_entry = ik->package();
1387 
1388   if (FileMapInfo::get_number_of_shared_paths() > 0) {
1389     char* canonical_path_table_entry = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, JVM_MAXPATHLEN);
1390 
1391     // save the path from the file: protocol or the module name from the jrt: protocol
1392     // if no protocol prefix is found, path is the same as stream->source()
1393     char* path = skip_uri_protocol(src);
1394     char* canonical_class_src_path = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, JVM_MAXPATHLEN);
1395     bool success = get_canonical_path(path, canonical_class_src_path, JVM_MAXPATHLEN);
1396     // The path is from the ClassFileStream. Since a ClassFileStream has been created successfully in functions
1397     // such as ClassLoader::load_class(), its source path must be valid.
1398     assert(success, "must be valid path");
1399     for (int i = 0; i < FileMapInfo::get_number_of_shared_paths(); i++) {
1400       SharedClassPathEntry* ent = FileMapInfo::shared_path(i);
1401       success = get_canonical_path(ent->name(), canonical_path_table_entry, JVM_MAXPATHLEN);
1402       // A shared path has been validated during its creation in ClassLoader::create_class_path_entry(),
1403       // it must be valid here.
1404       assert(success, "must be valid path");
1405       // If the path (from the class stream source) is the same as the shared
1406       // class or module path, then we have a match.
1407       if (strcmp(canonical_path_table_entry, canonical_class_src_path) == 0) {
1408         // NULL pkg_entry and pkg_entry in an unnamed module implies the class
1409         // is from the -cp or boot loader append path which consists of -Xbootclasspath/a
1410         // and jvmti appended entries.
1411         if ((pkg_entry == NULL) || (pkg_entry->in_unnamed_module())) {
1412           // Ensure the index is within the -cp range before assigning
1413           // to the classpath_index.
1414           if (SystemDictionary::is_system_class_loader(loader) &&
1415               (i >= ClassLoaderExt::app_class_paths_start_index()) &&
1416               (i < ClassLoaderExt::app_module_paths_start_index())) {
1417             classpath_index = i;
1418             break;
1419           } else {
1420             if ((i >= 1) &&
1421                 (i < ClassLoaderExt::app_class_paths_start_index())) {
1422               // The class must be from boot loader append path which consists of
1423               // -Xbootclasspath/a and jvmti appended entries.
1424               assert(loader == NULL, "sanity");
1425               classpath_index = i;
1426               break;
1427             }
1428           }
1429         } else {
1430           // A class from a named module from the --module-path. Ensure the index is
1431           // within the --module-path range before assigning to the classpath_index.
1432           if ((pkg_entry != NULL) && !(pkg_entry->in_unnamed_module()) && (i > 0)) {
1433             if (i >= ClassLoaderExt::app_module_paths_start_index() &&
1434                 i < FileMapInfo::get_number_of_shared_paths()) {
1435               classpath_index = i;
1436               break;
1437             }
1438           }
1439         }
1440       }
1441       // for index 0 and the stream->source() is the modules image or has the jrt: protocol.
1442       // The class must be from the runtime modules image.
1443       if (i == 0 && (stream->from_boot_loader_modules_image() || string_starts_with(src, "jrt:"))) {
1444         classpath_index = i;
1445         break;
1446       }
1447     }
1448 
1449     // No path entry found for this class. Must be a shared class loaded by the
1450     // user defined classloader.
1451     if (classpath_index < 0) {
1452       assert(ik->shared_classpath_index() < 0, "Sanity");
1453       ik->set_shared_classpath_index(UNREGISTERED_INDEX);
1454       SystemDictionaryShared::set_shared_class_misc_info(ik, (ClassFileStream*)stream);
1455       return;
1456     }
1457   } else {
1458     // The shared path table is set up after module system initialization.
1459     // The path table contains no entry before that. Any classes loaded prior
1460     // to the setup of the shared path table must be from the modules image.
1461     assert(stream->from_boot_loader_modules_image(), "stream must be loaded by boot loader from modules image");
1462     assert(FileMapInfo::get_number_of_shared_paths() == 0, "shared path table must not have been setup");
1463     classpath_index = 0;
1464   }
1465 
1466   const char* const class_name = ik->name()->as_C_string();
1467   const char* const file_name = file_name_for_class_name(class_name,
1468                                                          ik->name()->utf8_length());
1469   assert(file_name != NULL, "invariant");
1470 
1471   ClassLoaderExt::record_result(classpath_index, ik, THREAD);
1472 }
1473 #endif // INCLUDE_CDS
1474 
1475 // Initialize the class loader's access to methods in libzip.  Parse and
1476 // process the boot classpath into a list ClassPathEntry objects.  Once
1477 // this list has been created, it must not change order (see class PackageInfo)
1478 // it can be appended to and is by jvmti and the kernel vm.
1479 
1480 void ClassLoader::initialize() {
1481   EXCEPTION_MARK;
1482 
1483   if (UsePerfData) {
1484     // jvmstat performance counters
1485     NEWPERFTICKCOUNTER(_perf_accumulated_time, SUN_CLS, "time");
1486     NEWPERFTICKCOUNTER(_perf_class_init_time, SUN_CLS, "classInitTime");
1487     NEWPERFTICKCOUNTER(_perf_class_init_selftime, SUN_CLS, "classInitTime.self");
1488     NEWPERFTICKCOUNTER(_perf_class_verify_time, SUN_CLS, "classVerifyTime");
1489     NEWPERFTICKCOUNTER(_perf_class_verify_selftime, SUN_CLS, "classVerifyTime.self");
1490     NEWPERFTICKCOUNTER(_perf_class_link_time, SUN_CLS, "classLinkedTime");
1491     NEWPERFTICKCOUNTER(_perf_class_link_selftime, SUN_CLS, "classLinkedTime.self");
1492     NEWPERFEVENTCOUNTER(_perf_classes_inited, SUN_CLS, "initializedClasses");
1493     NEWPERFEVENTCOUNTER(_perf_classes_linked, SUN_CLS, "linkedClasses");
1494     NEWPERFEVENTCOUNTER(_perf_classes_verified, SUN_CLS, "verifiedClasses");
1495 
1496     NEWPERFTICKCOUNTER(_perf_class_parse_time, SUN_CLS, "parseClassTime");
1497     NEWPERFTICKCOUNTER(_perf_class_parse_selftime, SUN_CLS, "parseClassTime.self");
1498     NEWPERFTICKCOUNTER(_perf_sys_class_lookup_time, SUN_CLS, "lookupSysClassTime");
1499     NEWPERFTICKCOUNTER(_perf_shared_classload_time, SUN_CLS, "sharedClassLoadTime");
1500     NEWPERFTICKCOUNTER(_perf_sys_classload_time, SUN_CLS, "sysClassLoadTime");
1501     NEWPERFTICKCOUNTER(_perf_app_classload_time, SUN_CLS, "appClassLoadTime");
1502     NEWPERFTICKCOUNTER(_perf_app_classload_selftime, SUN_CLS, "appClassLoadTime.self");
1503     NEWPERFEVENTCOUNTER(_perf_app_classload_count, SUN_CLS, "appClassLoadCount");
1504     NEWPERFTICKCOUNTER(_perf_define_appclasses, SUN_CLS, "defineAppClasses");
1505     NEWPERFTICKCOUNTER(_perf_define_appclass_time, SUN_CLS, "defineAppClassTime");
1506     NEWPERFTICKCOUNTER(_perf_define_appclass_selftime, SUN_CLS, "defineAppClassTime.self");
1507     NEWPERFBYTECOUNTER(_perf_app_classfile_bytes_read, SUN_CLS, "appClassBytes");
1508     NEWPERFBYTECOUNTER(_perf_sys_classfile_bytes_read, SUN_CLS, "sysClassBytes");
1509 
1510 
1511     // The following performance counters are added for measuring the impact
1512     // of the bug fix of 6365597. They are mainly focused on finding out
1513     // the behavior of system & user-defined classloader lock, whether
1514     // ClassLoader.loadClass/findClass is being called synchronized or not.
1515     NEWPERFEVENTCOUNTER(_sync_systemLoaderLockContentionRate, SUN_CLS,
1516                         "systemLoaderLockContentionRate");
1517     NEWPERFEVENTCOUNTER(_sync_nonSystemLoaderLockContentionRate, SUN_CLS,
1518                         "nonSystemLoaderLockContentionRate");
1519     NEWPERFEVENTCOUNTER(_sync_JVMFindLoadedClassLockFreeCounter, SUN_CLS,
1520                         "jvmFindLoadedClassNoLockCalls");
1521     NEWPERFEVENTCOUNTER(_sync_JVMDefineClassLockFreeCounter, SUN_CLS,
1522                         "jvmDefineClassNoLockCalls");
1523 
1524     NEWPERFEVENTCOUNTER(_sync_JNIDefineClassLockFreeCounter, SUN_CLS,
1525                         "jniDefineClassNoLockCalls");
1526 
1527     NEWPERFEVENTCOUNTER(_unsafe_defineClassCallCounter, SUN_CLS,
1528                         "unsafeDefineClassCalls");
1529   }
1530 
1531   // lookup zip library entry points
1532   load_zip_library();
1533   // lookup jimage library entry points
1534   load_jimage_library();
1535   setup_bootstrap_search_path();
1536 }
1537 
1538 #if INCLUDE_CDS
1539 void ClassLoader::initialize_shared_path() {
1540   if (Arguments::is_dumping_archive()) {
1541     ClassLoaderExt::setup_search_paths();
1542   }
1543 }
1544 
1545 void ClassLoader::initialize_module_path(TRAPS) {
1546   if (Arguments::is_dumping_archive()) {
1547     ClassLoaderExt::setup_module_paths(THREAD);
1548     FileMapInfo::allocate_shared_path_table();
1549   }
1550 }
1551 #endif
1552 
1553 jlong ClassLoader::classloader_time_ms() {
1554   return UsePerfData ?
1555     Management::ticks_to_ms(_perf_accumulated_time->get_value()) : -1;
1556 }
1557 
1558 jlong ClassLoader::class_init_count() {
1559   return UsePerfData ? _perf_classes_inited->get_value() : -1;
1560 }
1561 
1562 jlong ClassLoader::class_init_time_ms() {
1563   return UsePerfData ?
1564     Management::ticks_to_ms(_perf_class_init_time->get_value()) : -1;
1565 }
1566 
1567 jlong ClassLoader::class_verify_time_ms() {
1568   return UsePerfData ?
1569     Management::ticks_to_ms(_perf_class_verify_time->get_value()) : -1;
1570 }
1571 
1572 jlong ClassLoader::class_link_count() {
1573   return UsePerfData ? _perf_classes_linked->get_value() : -1;
1574 }
1575 
1576 jlong ClassLoader::class_link_time_ms() {
1577   return UsePerfData ?
1578     Management::ticks_to_ms(_perf_class_link_time->get_value()) : -1;
1579 }
1580 
1581 int ClassLoader::compute_Object_vtable() {
1582   // hardwired for JDK1.2 -- would need to duplicate class file parsing
1583   // code to determine actual value from file
1584   // Would be value '11' if finals were in vtable
1585   int JDK_1_2_Object_vtable_size = 5;
1586   return JDK_1_2_Object_vtable_size * vtableEntry::size();
1587 }
1588 
1589 
1590 void classLoader_init1() {
1591   ClassLoader::initialize();
1592 }
1593 
1594 // Complete the ClassPathEntry setup for the boot loader
1595 void ClassLoader::classLoader_init2(TRAPS) {
1596   // Setup the list of module/path pairs for --patch-module processing
1597   // This must be done after the SymbolTable is created in order
1598   // to use fast_compare on module names instead of a string compare.
1599   if (Arguments::get_patch_mod_prefix() != NULL) {
1600     setup_patch_mod_entries();
1601   }
1602 
1603   // Create the ModuleEntry for java.base (must occur after setup_patch_mod_entries
1604   // to successfully determine if java.base has been patched)
1605   create_javabase();
1606 
1607   // Setup the initial java.base/path pair for the exploded build entries.
1608   // As more modules are defined during module system initialization, more
1609   // entries will be added to the exploded build array.
1610   if (!has_jrt_entry()) {
1611     assert(!DumpSharedSpaces, "DumpSharedSpaces not supported with exploded module builds");
1612     assert(!DynamicDumpSharedSpaces, "DynamicDumpSharedSpaces not supported with exploded module builds");
1613     assert(!UseSharedSpaces, "UsedSharedSpaces not supported with exploded module builds");
1614     // Set up the boot loader's _exploded_entries list.  Note that this gets
1615     // done before loading any classes, by the same thread that will
1616     // subsequently do the first class load. So, no lock is needed for this.
1617     assert(_exploded_entries == NULL, "Should only get initialized once");
1618     _exploded_entries = new (ResourceObj::C_HEAP, mtModule)
1619       GrowableArray<ModuleClassPathList*>(EXPLODED_ENTRY_SIZE, true);
1620     add_to_exploded_build_list(vmSymbols::java_base(), CHECK);
1621   }
1622 }
1623 
1624 
1625 bool ClassLoader::get_canonical_path(const char* orig, char* out, int len) {
1626   assert(orig != NULL && out != NULL && len > 0, "bad arguments");
1627   if (CanonicalizeEntry != NULL) {
1628     JavaThread* THREAD = JavaThread::current();
1629     JNIEnv* env = THREAD->jni_environment();
1630     ResourceMark rm(THREAD);
1631 
1632     // os::native_path writes into orig_copy
1633     char* orig_copy = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, strlen(orig)+1);
1634     strcpy(orig_copy, orig);
1635     if ((CanonicalizeEntry)(env, os::native_path(orig_copy), out, len) < 0) {
1636       return false;
1637     }
1638   } else {
1639     // On JDK 1.2.2 the Canonicalize does not exist, so just do nothing
1640     strncpy(out, orig, len);
1641     out[len - 1] = '\0';
1642   }
1643   return true;
1644 }
1645 
1646 void ClassLoader::create_javabase() {
1647   Thread* THREAD = Thread::current();
1648 
1649   // Create java.base's module entry for the boot
1650   // class loader prior to loading j.l.Ojbect.
1651   ClassLoaderData* null_cld = ClassLoaderData::the_null_class_loader_data();
1652 
1653   // Get module entry table
1654   ModuleEntryTable* null_cld_modules = null_cld->modules();
1655   if (null_cld_modules == NULL) {
1656     vm_exit_during_initialization("No ModuleEntryTable for the boot class loader");
1657   }
1658 
1659   {
1660     MutexLocker ml(Module_lock, THREAD);
1661     ModuleEntry* jb_module = null_cld_modules->locked_create_entry(Handle(),
1662                                false, vmSymbols::java_base(), NULL, NULL, null_cld);
1663     if (jb_module == NULL) {
1664       vm_exit_during_initialization("Unable to create ModuleEntry for " JAVA_BASE_NAME);
1665     }
1666     ModuleEntryTable::set_javabase_moduleEntry(jb_module);
1667   }
1668 }
1669 
1670 // Please keep following two functions at end of this file. With them placed at top or in middle of the file,
1671 // they could get inlined by agressive compiler, an unknown trick, see bug 6966589.
1672 void PerfClassTraceTime::initialize() {
1673   if (!UsePerfData) return;
1674 
1675   if (_eventp != NULL) {
1676     // increment the event counter
1677     _eventp->inc();
1678   }
1679 
1680   // stop the current active thread-local timer to measure inclusive time
1681   _prev_active_event = -1;
1682   for (int i=0; i < EVENT_TYPE_COUNT; i++) {
1683      if (_timers[i].is_active()) {
1684        assert(_prev_active_event == -1, "should have only one active timer");
1685        _prev_active_event = i;
1686        _timers[i].stop();
1687      }
1688   }
1689 
1690   if (_recursion_counters == NULL || (_recursion_counters[_event_type])++ == 0) {
1691     // start the inclusive timer if not recursively called
1692     _t.start();
1693   }
1694 
1695   // start thread-local timer of the given event type
1696    if (!_timers[_event_type].is_active()) {
1697     _timers[_event_type].start();
1698   }
1699 }
1700 
1701 PerfClassTraceTime::~PerfClassTraceTime() {
1702   if (!UsePerfData) return;
1703 
1704   // stop the thread-local timer as the event completes
1705   // and resume the thread-local timer of the event next on the stack
1706   _timers[_event_type].stop();
1707   jlong selftime = _timers[_event_type].ticks();
1708 
1709   if (_prev_active_event >= 0) {
1710     _timers[_prev_active_event].start();
1711   }
1712 
1713   if (_recursion_counters != NULL && --(_recursion_counters[_event_type]) > 0) return;
1714 
1715   // increment the counters only on the leaf call
1716   _t.stop();
1717   _timep->inc(_t.ticks());
1718   if (_selftimep != NULL) {
1719     _selftimep->inc(selftime);
1720   }
1721   // add all class loading related event selftime to the accumulated time counter
1722   ClassLoader::perf_accumulated_time()->inc(selftime);
1723 
1724   // reset the timer
1725   _timers[_event_type].reset();
1726 }