1 /*
   2  * Copyright (c) 1997, 2017, 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 "classfile/classFileStream.hpp"
  27 #include "classfile/classLoader.hpp"
  28 #include "classfile/classLoaderData.inline.hpp"
  29 #include "classfile/classLoaderExt.hpp"
  30 #include "classfile/javaClasses.hpp"
  31 #include "classfile/jimage.hpp"
  32 #include "classfile/moduleEntry.hpp"
  33 #include "classfile/modules.hpp"
  34 #include "classfile/packageEntry.hpp"
  35 #include "classfile/klassFactory.hpp"
  36 #include "classfile/systemDictionary.hpp"
  37 #include "classfile/vmSymbols.hpp"
  38 #include "compiler/compileBroker.hpp"
  39 #include "gc/shared/collectedHeap.inline.hpp"
  40 #include "gc/shared/generation.hpp"
  41 #include "interpreter/bytecodeStream.hpp"
  42 #include "interpreter/oopMapCache.hpp"
  43 #include "logging/logTag.hpp"
  44 #include "memory/allocation.inline.hpp"
  45 #include "memory/filemap.hpp"
  46 #include "memory/oopFactory.hpp"
  47 #include "memory/resourceArea.hpp"
  48 #include "memory/universe.inline.hpp"
  49 #include "oops/instanceKlass.hpp"
  50 #include "oops/instanceRefKlass.hpp"
  51 #include "oops/objArrayOop.inline.hpp"
  52 #include "oops/oop.inline.hpp"
  53 #include "oops/symbol.hpp"
  54 #include "prims/jvm_misc.hpp"
  55 #include "runtime/arguments.hpp"
  56 #include "runtime/compilationPolicy.hpp"
  57 #include "runtime/fprofiler.hpp"
  58 #include "runtime/handles.hpp"
  59 #include "runtime/handles.inline.hpp"
  60 #include "runtime/init.hpp"
  61 #include "runtime/interfaceSupport.hpp"
  62 #include "runtime/java.hpp"
  63 #include "runtime/javaCalls.hpp"
  64 #include "runtime/os.hpp"
  65 #include "runtime/threadCritical.hpp"
  66 #include "runtime/timer.hpp"
  67 #include "runtime/vm_version.hpp"
  68 #include "services/management.hpp"
  69 #include "services/threadService.hpp"
  70 #include "utilities/events.hpp"
  71 #include "utilities/hashtable.inline.hpp"
  72 #include "utilities/macros.hpp"
  73 #if INCLUDE_CDS
  74 #include "classfile/sharedClassUtil.hpp"
  75 #include "classfile/sharedPathsMiscInfo.hpp"
  76 #endif
  77 
  78 // Entry points in zip.dll for loading zip/jar file entries
  79 
  80 typedef void * * (JNICALL *ZipOpen_t)(const char *name, char **pmsg);
  81 typedef void (JNICALL *ZipClose_t)(jzfile *zip);
  82 typedef jzentry* (JNICALL *FindEntry_t)(jzfile *zip, const char *name, jint *sizeP, jint *nameLen);
  83 typedef jboolean (JNICALL *ReadEntry_t)(jzfile *zip, jzentry *entry, unsigned char *buf, char *namebuf);
  84 typedef jzentry* (JNICALL *GetNextEntry_t)(jzfile *zip, jint n);
  85 typedef jboolean (JNICALL *ZipInflateFully_t)(void *inBuf, jlong inLen, void *outBuf, jlong outLen, char **pmsg);
  86 typedef jint     (JNICALL *Crc32_t)(jint crc, const jbyte *buf, jint len);
  87 
  88 static ZipOpen_t         ZipOpen            = NULL;
  89 static ZipClose_t        ZipClose           = NULL;
  90 static FindEntry_t       FindEntry          = NULL;
  91 static ReadEntry_t       ReadEntry          = NULL;
  92 static GetNextEntry_t    GetNextEntry       = NULL;
  93 static canonicalize_fn_t CanonicalizeEntry  = NULL;
  94 static ZipInflateFully_t ZipInflateFully    = NULL;
  95 static Crc32_t           Crc32              = NULL;
  96 
  97 // Entry points for jimage.dll for loading jimage file entries
  98 
  99 static JImageOpen_t                    JImageOpen             = NULL;
 100 static JImageClose_t                   JImageClose            = NULL;
 101 static JImagePackageToModule_t         JImagePackageToModule  = NULL;
 102 static JImageFindResource_t            JImageFindResource     = NULL;
 103 static JImageGetResource_t             JImageGetResource      = NULL;
 104 static JImageResourceIterator_t        JImageResourceIterator = NULL;
 105 static JImage_ResourcePath_t           JImageResourcePath     = NULL;
 106 
 107 // Globals
 108 
 109 PerfCounter*    ClassLoader::_perf_accumulated_time = NULL;
 110 PerfCounter*    ClassLoader::_perf_classes_inited = NULL;
 111 PerfCounter*    ClassLoader::_perf_class_init_time = NULL;
 112 PerfCounter*    ClassLoader::_perf_class_init_selftime = NULL;
 113 PerfCounter*    ClassLoader::_perf_classes_verified = NULL;
 114 PerfCounter*    ClassLoader::_perf_class_verify_time = NULL;
 115 PerfCounter*    ClassLoader::_perf_class_verify_selftime = NULL;
 116 PerfCounter*    ClassLoader::_perf_classes_linked = NULL;
 117 PerfCounter*    ClassLoader::_perf_class_link_time = NULL;
 118 PerfCounter*    ClassLoader::_perf_class_link_selftime = NULL;
 119 PerfCounter*    ClassLoader::_perf_class_parse_time = NULL;
 120 PerfCounter*    ClassLoader::_perf_class_parse_selftime = NULL;
 121 PerfCounter*    ClassLoader::_perf_sys_class_lookup_time = NULL;
 122 PerfCounter*    ClassLoader::_perf_shared_classload_time = NULL;
 123 PerfCounter*    ClassLoader::_perf_sys_classload_time = NULL;
 124 PerfCounter*    ClassLoader::_perf_app_classload_time = NULL;
 125 PerfCounter*    ClassLoader::_perf_app_classload_selftime = NULL;
 126 PerfCounter*    ClassLoader::_perf_app_classload_count = NULL;
 127 PerfCounter*    ClassLoader::_perf_define_appclasses = NULL;
 128 PerfCounter*    ClassLoader::_perf_define_appclass_time = NULL;
 129 PerfCounter*    ClassLoader::_perf_define_appclass_selftime = NULL;
 130 PerfCounter*    ClassLoader::_perf_app_classfile_bytes_read = NULL;
 131 PerfCounter*    ClassLoader::_perf_sys_classfile_bytes_read = NULL;
 132 PerfCounter*    ClassLoader::_sync_systemLoaderLockContentionRate = NULL;
 133 PerfCounter*    ClassLoader::_sync_nonSystemLoaderLockContentionRate = NULL;
 134 PerfCounter*    ClassLoader::_sync_JVMFindLoadedClassLockFreeCounter = NULL;
 135 PerfCounter*    ClassLoader::_sync_JVMDefineClassLockFreeCounter = NULL;
 136 PerfCounter*    ClassLoader::_sync_JNIDefineClassLockFreeCounter = NULL;
 137 PerfCounter*    ClassLoader::_unsafe_defineClassCallCounter = NULL;
 138 PerfCounter*    ClassLoader::_isUnsyncloadClass = NULL;
 139 PerfCounter*    ClassLoader::_load_instance_class_failCounter = NULL;
 140 
 141 GrowableArray<ModuleClassPathList*>* ClassLoader::_patch_mod_entries = NULL;
 142 GrowableArray<ModuleClassPathList*>* ClassLoader::_exploded_entries = NULL;
 143 ClassPathEntry* ClassLoader::_jrt_entry = NULL;
 144 ClassPathEntry* ClassLoader::_first_append_entry = NULL;
 145 ClassPathEntry* ClassLoader::_last_append_entry  = NULL;
 146 int             ClassLoader::_num_entries        = 0;
 147 #if INCLUDE_CDS
 148 GrowableArray<char*>* ClassLoader::_boot_modules_array = NULL;
 149 GrowableArray<char*>* ClassLoader::_platform_modules_array = NULL;
 150 SharedPathsMiscInfo* ClassLoader::_shared_paths_misc_info = NULL;
 151 #endif
 152 
 153 // helper routines
 154 bool string_starts_with(const char* str, const char* str_to_find) {
 155   size_t str_len = strlen(str);
 156   size_t str_to_find_len = strlen(str_to_find);
 157   if (str_to_find_len > str_len) {
 158     return false;
 159   }
 160   return (strncmp(str, str_to_find, str_to_find_len) == 0);
 161 }
 162 
 163 static const char* get_jimage_version_string() {
 164   static char version_string[10] = "";
 165   if (version_string[0] == '\0') {
 166     jio_snprintf(version_string, sizeof(version_string), "%d.%d",
 167                  Abstract_VM_Version::vm_major_version(), Abstract_VM_Version::vm_minor_version());
 168   }
 169   return (const char*)version_string;
 170 }
 171 
 172 bool ClassLoader::string_ends_with(const char* str, const char* str_to_find) {
 173   size_t str_len = strlen(str);
 174   size_t str_to_find_len = strlen(str_to_find);
 175   if (str_to_find_len > str_len) {
 176     return false;
 177   }
 178   return (strncmp(str + (str_len - str_to_find_len), str_to_find, str_to_find_len) == 0);
 179 }
 180 
 181 // Used to obtain the package name from a fully qualified class name.
 182 // It is the responsibility of the caller to establish a ResourceMark.
 183 const char* ClassLoader::package_from_name(const char* const class_name, bool* bad_class_name) {
 184   if (class_name == NULL) {
 185     if (bad_class_name != NULL) {
 186       *bad_class_name = true;
 187     }
 188     return NULL;
 189   }
 190 
 191   if (bad_class_name != NULL) {
 192     *bad_class_name = false;
 193   }
 194 
 195   const char* const last_slash = strrchr(class_name, '/');
 196   if (last_slash == NULL) {
 197     // No package name
 198     return NULL;
 199   }
 200 
 201   char* class_name_ptr = (char*) class_name;
 202   // Skip over '['s
 203   if (*class_name_ptr == '[') {
 204     do {
 205       class_name_ptr++;
 206     } while (*class_name_ptr == '[');
 207 
 208     // Fully qualified class names should not contain a 'L'.
 209     // Set bad_class_name to true to indicate that the package name
 210     // could not be obtained due to an error condition.
 211     // In this situation, is_same_class_package returns false.
 212     if (*class_name_ptr == 'L' || *class_name_ptr == 'Q') {
 213       if (bad_class_name != NULL) {
 214         *bad_class_name = true;
 215       }
 216       return NULL;
 217     }
 218   }
 219 
 220   int length = last_slash - class_name_ptr;
 221 
 222   // A class name could have just the slash character in the name.
 223   if (length <= 0) {
 224     // No package name
 225     if (bad_class_name != NULL) {
 226       *bad_class_name = true;
 227     }
 228     return NULL;
 229   }
 230 
 231   // drop name after last slash (including slash)
 232   // Ex., "java/lang/String.class" => "java/lang"
 233   char* pkg_name = NEW_RESOURCE_ARRAY(char, length + 1);
 234   strncpy(pkg_name, class_name_ptr, length);
 235   *(pkg_name+length) = '\0';
 236 
 237   return (const char *)pkg_name;
 238 }
 239 
 240 // Given a fully qualified class name, find its defining package in the class loader's
 241 // package entry table.
 242 static PackageEntry* get_package_entry(const char* class_name, ClassLoaderData* loader_data, TRAPS) {
 243   ResourceMark rm(THREAD);
 244   const char *pkg_name = ClassLoader::package_from_name(class_name);
 245   if (pkg_name == NULL) {
 246     return NULL;
 247   }
 248   PackageEntryTable* pkgEntryTable = loader_data->packages();
 249   TempNewSymbol pkg_symbol = SymbolTable::new_symbol(pkg_name, CHECK_NULL);
 250   return pkgEntryTable->lookup_only(pkg_symbol);
 251 }
 252 
 253 ClassPathDirEntry::ClassPathDirEntry(const char* dir) : ClassPathEntry() {
 254   char* copy = NEW_C_HEAP_ARRAY(char, strlen(dir)+1, mtClass);
 255   strcpy(copy, dir);
 256   _dir = copy;
 257 }
 258 
 259 
 260 ClassFileStream* ClassPathDirEntry::open_stream(const char* name, TRAPS) {
 261   // construct full path name
 262   char* path = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, JVM_MAXPATHLEN);
 263   if (jio_snprintf(path, JVM_MAXPATHLEN, "%s%s%s", _dir, os::file_separator(), name) == -1) {
 264     FREE_RESOURCE_ARRAY(char, path, JVM_MAXPATHLEN);
 265     return NULL;
 266   }
 267   // check if file exists
 268   struct stat st;
 269   if (os::stat(path, &st) == 0) {
 270 #if INCLUDE_CDS
 271     if (DumpSharedSpaces) {
 272       // We have already check in ClassLoader::check_shared_classpath() that the directory is empty, so
 273       // we should never find a file underneath it -- unless user has added a new file while we are running
 274       // the dump, in which case let's quit!
 275       ShouldNotReachHere();
 276     }
 277 #endif
 278     // found file, open it
 279     int file_handle = os::open(path, 0, 0);
 280     if (file_handle != -1) {
 281       // read contents into resource array
 282       u1* buffer = NEW_RESOURCE_ARRAY(u1, st.st_size);
 283       size_t num_read = os::read(file_handle, (char*) buffer, st.st_size);
 284       // close file
 285       os::close(file_handle);
 286       // construct ClassFileStream
 287       if (num_read == (size_t)st.st_size) {
 288         if (UsePerfData) {
 289           ClassLoader::perf_sys_classfile_bytes_read()->inc(num_read);
 290         }
 291         FREE_RESOURCE_ARRAY(char, path, JVM_MAXPATHLEN);
 292         // Resource allocated
 293         return new ClassFileStream(buffer,
 294                                    st.st_size,
 295                                    _dir,
 296                                    ClassFileStream::verify);
 297       }
 298     }
 299   }
 300   FREE_RESOURCE_ARRAY(char, path, JVM_MAXPATHLEN);
 301   return NULL;
 302 }
 303 
 304 ClassPathZipEntry::ClassPathZipEntry(jzfile* zip, const char* zip_name, bool is_boot_append) : ClassPathEntry() {
 305   _zip = zip;
 306   char *copy = NEW_C_HEAP_ARRAY(char, strlen(zip_name)+1, mtClass);
 307   strcpy(copy, zip_name);
 308   _zip_name = copy;
 309   _is_boot_append = is_boot_append;
 310   _multi_versioned = _unknown;
 311 }
 312 
 313 ClassPathZipEntry::~ClassPathZipEntry() {
 314   if (ZipClose != NULL) {
 315     (*ZipClose)(_zip);
 316   }
 317   FREE_C_HEAP_ARRAY(char, _zip_name);
 318 }
 319 
 320 u1* ClassPathZipEntry::open_entry(const char* name, jint* filesize, bool nul_terminate, TRAPS) {
 321     // enable call to C land
 322   JavaThread* thread = JavaThread::current();
 323   ThreadToNativeFromVM ttn(thread);
 324   // check whether zip archive contains name
 325   jint name_len;
 326   jzentry* entry = (*FindEntry)(_zip, name, filesize, &name_len);
 327   if (entry == NULL) return NULL;
 328   u1* buffer;
 329   char name_buf[128];
 330   char* filename;
 331   if (name_len < 128) {
 332     filename = name_buf;
 333   } else {
 334     filename = NEW_RESOURCE_ARRAY(char, name_len + 1);
 335   }
 336 
 337   // read contents into resource array
 338   int size = (*filesize) + ((nul_terminate) ? 1 : 0);
 339   buffer = NEW_RESOURCE_ARRAY(u1, size);
 340   if (!(*ReadEntry)(_zip, entry, buffer, filename)) return NULL;
 341 
 342   // return result
 343   if (nul_terminate) {
 344     buffer[*filesize] = 0;
 345   }
 346   return buffer;
 347 }
 348 
 349 #if INCLUDE_CDS
 350 u1* ClassPathZipEntry::open_versioned_entry(const char* name, jint* filesize, TRAPS) {
 351   u1* buffer = NULL;
 352   if (DumpSharedSpaces && !_is_boot_append) {
 353     // We presume default is multi-release enabled
 354     const char* multi_ver = Arguments::get_property("jdk.util.jar.enableMultiRelease");
 355     const char* verstr = Arguments::get_property("jdk.util.jar.version");
 356     bool is_multi_ver = (multi_ver == NULL ||
 357                          strcmp(multi_ver, "true") == 0 ||
 358                          strcmp(multi_ver, "force")  == 0) &&
 359                          is_multiple_versioned(THREAD);
 360     // command line version setting
 361     int version = 0;
 362     const int base_version = 8; // JDK8
 363     int cur_ver = JDK_Version::current().major_version();
 364     if (verstr != NULL) {
 365       version = atoi(verstr);
 366       if (version < base_version || version > cur_ver) {
 367         // If the specified version is lower than the base version, the base
 368         // entry will be used; if the version is higher than the current
 369         // jdk version, the highest versioned entry will be used.
 370         if (version < base_version) {
 371           is_multi_ver = false;
 372         }
 373         // print out warning, do not use assertion here since it will continue to look
 374         // for proper version.
 375         warning("JDK%d is not supported in multiple version jars", version);
 376       }
 377     }
 378 
 379     if (is_multi_ver) {
 380       int n;
 381       char* entry_name = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, JVM_MAXPATHLEN);
 382       if (version > 0) {
 383         n = jio_snprintf(entry_name, JVM_MAXPATHLEN, "META-INF/versions/%d/%s", version, name);
 384         entry_name[n] = '\0';
 385         buffer = open_entry((const char*)entry_name, filesize, false, CHECK_NULL);
 386         if (buffer == NULL) {
 387           warning("Could not find %s in %s, try to find highest version instead", entry_name, _zip_name);
 388         }
 389       }
 390       if (buffer == NULL) {
 391         for (int i = cur_ver; i >= base_version; i--) {
 392           n = jio_snprintf(entry_name, JVM_MAXPATHLEN, "META-INF/versions/%d/%s", i, name);
 393           entry_name[n] = '\0';
 394           buffer = open_entry((const char*)entry_name, filesize, false, CHECK_NULL);
 395           if (buffer != NULL) {
 396             break;
 397           }
 398         }
 399       }
 400       FREE_RESOURCE_ARRAY(char, entry_name, JVM_MAXPATHLEN);
 401     }
 402   }
 403   return buffer;
 404 }
 405 
 406 bool ClassPathZipEntry::is_multiple_versioned(TRAPS) {
 407   assert(DumpSharedSpaces, "called only at dump time");
 408   if (_multi_versioned != _unknown) {
 409     return (_multi_versioned == _yes) ? true : false;
 410   }
 411   jint size;
 412   char* buffer = (char*)open_entry("META-INF/MANIFEST.MF", &size, true, CHECK_false);
 413   if (buffer != NULL) {
 414     char* p = buffer;
 415     for ( ; *p; ++p) *p = tolower(*p);
 416     if (strstr(buffer, "multi-release: true") != NULL) {
 417       _multi_versioned = _yes;
 418       return true;
 419     }
 420   }
 421   _multi_versioned = _no;
 422   return false;
 423 }
 424 #endif // INCLUDE_CDS
 425 
 426 ClassFileStream* ClassPathZipEntry::open_stream(const char* name, TRAPS) {
 427   jint filesize;
 428   u1* buffer = open_versioned_entry(name, &filesize, CHECK_NULL);
 429   if (buffer == NULL) {
 430     buffer = open_entry(name, &filesize, false, CHECK_NULL);
 431     if (buffer == NULL) {
 432       return NULL;
 433     }
 434   }
 435   if (UsePerfData) {
 436     ClassLoader::perf_sys_classfile_bytes_read()->inc(filesize);
 437   }
 438   // Resource allocated
 439   return new ClassFileStream(buffer,
 440                              filesize,
 441                              _zip_name,
 442                              ClassFileStream::verify);
 443 }
 444 
 445 // invoke function for each entry in the zip file
 446 void ClassPathZipEntry::contents_do(void f(const char* name, void* context), void* context) {
 447   JavaThread* thread = JavaThread::current();
 448   HandleMark  handle_mark(thread);
 449   ThreadToNativeFromVM ttn(thread);
 450   for (int n = 0; ; n++) {
 451     jzentry * ze = ((*GetNextEntry)(_zip, n));
 452     if (ze == NULL) break;
 453     (*f)(ze->name, context);
 454   }
 455 }
 456 
 457 ClassPathImageEntry::ClassPathImageEntry(JImageFile* jimage, const char* name) :
 458   ClassPathEntry(),
 459   _jimage(jimage) {
 460   guarantee(jimage != NULL, "jimage file is null");
 461   guarantee(name != NULL, "jimage file name is null");
 462   size_t len = strlen(name) + 1;
 463   _name = NEW_C_HEAP_ARRAY(const char, len, mtClass);
 464   strncpy((char *)_name, name, len);
 465 }
 466 
 467 ClassPathImageEntry::~ClassPathImageEntry() {
 468   if (_name != NULL) {
 469     FREE_C_HEAP_ARRAY(const char, _name);
 470     _name = NULL;
 471   }
 472   if (_jimage != NULL) {
 473     (*JImageClose)(_jimage);
 474     _jimage = NULL;
 475   }
 476 }
 477 
 478 // For a class in a named module, look it up in the jimage file using this syntax:
 479 //    /<module-name>/<package-name>/<base-class>
 480 //
 481 // Assumptions:
 482 //     1. There are no unnamed modules in the jimage file.
 483 //     2. A package is in at most one module in the jimage file.
 484 //
 485 ClassFileStream* ClassPathImageEntry::open_stream(const char* name, TRAPS) {
 486   jlong size;
 487   JImageLocationRef location = (*JImageFindResource)(_jimage, "", get_jimage_version_string(), name, &size);
 488 
 489   if (location == 0) {
 490     ResourceMark rm;
 491     const char* pkg_name = ClassLoader::package_from_name(name);
 492 
 493     if (pkg_name != NULL) {
 494       if (!Universe::is_module_initialized()) {
 495         location = (*JImageFindResource)(_jimage, JAVA_BASE_NAME, get_jimage_version_string(), name, &size);
 496 #if INCLUDE_CDS
 497         // CDS uses the boot class loader to load classes whose packages are in
 498         // modules defined for other class loaders.  So, for now, get their module
 499         // names from the "modules" jimage file.
 500         if (DumpSharedSpaces && location == 0) {
 501           const char* module_name = (*JImagePackageToModule)(_jimage, pkg_name);
 502           if (module_name != NULL) {
 503             location = (*JImageFindResource)(_jimage, module_name, get_jimage_version_string(), name, &size);
 504           }
 505         }
 506 #endif
 507 
 508       } else {
 509         PackageEntry* package_entry = get_package_entry(name, ClassLoaderData::the_null_class_loader_data(), CHECK_NULL);
 510         if (package_entry != NULL) {
 511           ResourceMark rm;
 512           // Get the module name
 513           ModuleEntry* module = package_entry->module();
 514           assert(module != NULL, "Boot classLoader package missing module");
 515           assert(module->is_named(), "Boot classLoader package is in unnamed module");
 516           const char* module_name = module->name()->as_C_string();
 517           if (module_name != NULL) {
 518             location = (*JImageFindResource)(_jimage, module_name, get_jimage_version_string(), name, &size);
 519           }
 520         }
 521       }
 522     }
 523   }
 524   if (location != 0) {
 525     if (UsePerfData) {
 526       ClassLoader::perf_sys_classfile_bytes_read()->inc(size);
 527     }
 528     char* data = NEW_RESOURCE_ARRAY(char, size);
 529     (*JImageGetResource)(_jimage, location, data, size);
 530     // Resource allocated
 531     return new ClassFileStream((u1*)data,
 532                                (int)size,
 533                                _name,
 534                                ClassFileStream::verify);
 535   }
 536 
 537   return NULL;
 538 }
 539 
 540 #ifndef PRODUCT
 541 bool ctw_visitor(JImageFile* jimage,
 542         const char* module_name, const char* version, const char* package,
 543         const char* name, const char* extension, void* arg) {
 544   if (strcmp(extension, "class") == 0) {
 545     Thread* THREAD = Thread::current();
 546     ResourceMark rm(THREAD);
 547     char* path = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, JIMAGE_MAX_PATH);
 548     jio_snprintf(path, JIMAGE_MAX_PATH - 1, "%s/%s.class", package, name);
 549     ClassLoader::compile_the_world_in(path, *(Handle*)arg, THREAD);
 550     return !HAS_PENDING_EXCEPTION;
 551   }
 552   return true;
 553 }
 554 
 555 void ClassPathImageEntry::compile_the_world(Handle loader, TRAPS) {
 556   tty->print_cr("CompileTheWorld : Compiling all classes in %s", name());
 557   tty->cr();
 558   (*JImageResourceIterator)(_jimage, (JImageResourceVisitor_t)ctw_visitor, (void *)&loader);
 559   if (HAS_PENDING_EXCEPTION) {
 560     if (PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())) {
 561       CLEAR_PENDING_EXCEPTION;
 562       tty->print_cr("\nCompileTheWorld : Ran out of memory\n");
 563       tty->print_cr("Increase class metadata storage if a limit was set");
 564     } else {
 565       tty->print_cr("\nCompileTheWorld : Unexpected exception occurred\n");
 566     }
 567   }
 568 }
 569 #endif
 570 
 571 bool ClassPathImageEntry::is_jrt() {
 572   return ClassLoader::is_jrt(name());
 573 }
 574 
 575 #if INCLUDE_CDS
 576 void ClassLoader::exit_with_path_failure(const char* error, const char* message) {
 577   assert(DumpSharedSpaces, "only called at dump time");
 578   tty->print_cr("Hint: enable -Xlog:class+path=info to diagnose the failure");
 579   vm_exit_during_initialization(error, message);
 580 }
 581 #endif
 582 
 583 ModuleClassPathList::ModuleClassPathList(Symbol* module_name) {
 584   _module_name = module_name;
 585   _module_first_entry = NULL;
 586   _module_last_entry = NULL;
 587 }
 588 
 589 ModuleClassPathList::~ModuleClassPathList() {
 590   // Clean out each ClassPathEntry on list
 591   ClassPathEntry* e = _module_first_entry;
 592   while (e != NULL) {
 593     ClassPathEntry* next_entry = e->next();
 594     delete e;
 595     e = next_entry;
 596   }
 597 }
 598 
 599 void ModuleClassPathList::add_to_list(ClassPathEntry* new_entry) {
 600   if (new_entry != NULL) {
 601     if (_module_last_entry == NULL) {
 602       _module_first_entry = _module_last_entry = new_entry;
 603     } else {
 604       _module_last_entry->set_next(new_entry);
 605       _module_last_entry = new_entry;
 606     }
 607   }
 608 }
 609 
 610 void ClassLoader::trace_class_path(const char* msg, const char* name) {
 611   if (log_is_enabled(Info, class, path)) {
 612     ResourceMark rm;
 613     outputStream* out = Log(class, path)::info_stream();
 614     if (msg) {
 615       out->print("%s", msg);
 616     }
 617     if (name) {
 618       if (strlen(name) < 256) {
 619         out->print("%s", name);
 620       } else {
 621         // For very long paths, we need to print each character separately,
 622         // as print_cr() has a length limit
 623         while (name[0] != '\0') {
 624           out->print("%c", name[0]);
 625           name++;
 626         }
 627       }
 628     }
 629     out->cr();
 630   }
 631 }
 632 
 633 #if INCLUDE_CDS
 634 void ClassLoader::check_shared_classpath(const char *path) {
 635   if (strcmp(path, "") == 0) {
 636     exit_with_path_failure("Cannot have empty path in archived classpaths", NULL);
 637   }
 638 
 639   struct stat st;
 640   if (os::stat(path, &st) == 0) {
 641     if ((st.st_mode & S_IFMT) != S_IFREG) { // is not a regular file
 642       if (!os::dir_is_empty(path)) {
 643         tty->print_cr("Error: non-empty directory '%s'", path);
 644         exit_with_path_failure("CDS allows only empty directories in archived classpaths", NULL);
 645       }
 646     }
 647   }
 648 }
 649 #endif
 650 
 651 void ClassLoader::setup_bootstrap_search_path() {
 652   const char* sys_class_path = Arguments::get_sysclasspath();
 653   const char* java_class_path = Arguments::get_appclasspath();
 654   if (PrintSharedArchiveAndExit) {
 655     // Don't print sys_class_path - this is the bootcp of this current VM process, not necessarily
 656     // the same as the bootcp of the shared archive.
 657   } else {
 658     trace_class_path("bootstrap loader class path=", sys_class_path);
 659     trace_class_path("classpath: ", java_class_path);
 660   }
 661 #if INCLUDE_CDS
 662   if (DumpSharedSpaces) {
 663     _shared_paths_misc_info->add_boot_classpath(sys_class_path);
 664   }
 665 #endif
 666   setup_search_path(sys_class_path, true);
 667 }
 668 
 669 #if INCLUDE_CDS
 670 int ClassLoader::get_shared_paths_misc_info_size() {
 671   return _shared_paths_misc_info->get_used_bytes();
 672 }
 673 
 674 void* ClassLoader::get_shared_paths_misc_info() {
 675   return _shared_paths_misc_info->buffer();
 676 }
 677 
 678 bool ClassLoader::check_shared_paths_misc_info(void *buf, int size) {
 679   SharedPathsMiscInfo* checker = SharedClassUtil::allocate_shared_paths_misc_info((char*)buf, size);
 680   bool result = checker->check();
 681   delete checker;
 682   return result;
 683 }
 684 #endif
 685 
 686 // Construct the array of module/path pairs as specified to --patch-module
 687 // for the boot loader to search ahead of the jimage, if the class being
 688 // loaded is defined to a module that has been specified to --patch-module.
 689 void ClassLoader::setup_patch_mod_entries() {
 690   Thread* THREAD = Thread::current();
 691   GrowableArray<ModulePatchPath*>* patch_mod_args = Arguments::get_patch_mod_prefix();
 692   int num_of_entries = patch_mod_args->length();
 693 
 694 
 695   // Set up the boot loader's _patch_mod_entries list
 696   _patch_mod_entries = new (ResourceObj::C_HEAP, mtModule) GrowableArray<ModuleClassPathList*>(num_of_entries, true);
 697 
 698   for (int i = 0; i < num_of_entries; i++) {
 699     const char* module_name = (patch_mod_args->at(i))->module_name();
 700     Symbol* const module_sym = SymbolTable::lookup(module_name, (int)strlen(module_name), CHECK);
 701     assert(module_sym != NULL, "Failed to obtain Symbol for module name");
 702     ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
 703 
 704     char* class_path = (patch_mod_args->at(i))->path_string();
 705     int len = (int)strlen(class_path);
 706     int end = 0;
 707     // Iterate over the module's class path entries
 708     for (int start = 0; start < len; start = end) {
 709       while (class_path[end] && class_path[end] != os::path_separator()[0]) {
 710         end++;
 711       }
 712       EXCEPTION_MARK;
 713       ResourceMark rm(THREAD);
 714       char* path = NEW_RESOURCE_ARRAY(char, end - start + 1);
 715       strncpy(path, &class_path[start], end - start);
 716       path[end - start] = '\0';
 717 
 718       struct stat st;
 719       if (os::stat(path, &st) == 0) {
 720         // File or directory found
 721         Thread* THREAD = Thread::current();
 722         ClassPathEntry* new_entry = create_class_path_entry(path, &st, false, false, CHECK);
 723         // If the path specification is valid, enter it into this module's list
 724         if (new_entry != NULL) {
 725           module_cpl->add_to_list(new_entry);
 726         }
 727       }
 728 
 729       while (class_path[end] == os::path_separator()[0]) {
 730         end++;
 731       }
 732     }
 733 
 734     // Record the module into the list of --patch-module entries only if
 735     // valid ClassPathEntrys have been created
 736     if (module_cpl->module_first_entry() != NULL) {
 737       _patch_mod_entries->push(module_cpl);
 738     }
 739   }
 740 }
 741 
 742 // Determine whether the module has been patched via the command-line
 743 // option --patch-module
 744 bool ClassLoader::is_in_patch_mod_entries(Symbol* module_name) {
 745   if (_patch_mod_entries != NULL && _patch_mod_entries->is_nonempty()) {
 746     int table_len = _patch_mod_entries->length();
 747     for (int i = 0; i < table_len; i++) {
 748       ModuleClassPathList* patch_mod = _patch_mod_entries->at(i);
 749       if (module_name->fast_compare(patch_mod->module_name()) == 0) {
 750         return true;
 751       }
 752     }
 753   }
 754   return false;
 755 }
 756 
 757 void ClassLoader::setup_search_path(const char *class_path, bool bootstrap_search) {
 758   int len = (int)strlen(class_path);
 759   int end = 0;
 760   bool set_base_piece = bootstrap_search;
 761 
 762   // Iterate over class path entries
 763   for (int start = 0; start < len; start = end) {
 764     while (class_path[end] && class_path[end] != os::path_separator()[0]) {
 765       end++;
 766     }
 767     EXCEPTION_MARK;
 768     ResourceMark rm(THREAD);
 769     char* path = NEW_RESOURCE_ARRAY(char, end - start + 1);
 770     strncpy(path, &class_path[start], end - start);
 771     path[end - start] = '\0';
 772 
 773     // The first time through the bootstrap_search setup, it must be determined
 774     // what the base or core piece of the boot loader search is.  Either a java runtime
 775     // image is present or this is an exploded module build situation.
 776     if (set_base_piece) {
 777       assert(string_ends_with(path, MODULES_IMAGE_NAME) || string_ends_with(path, JAVA_BASE_NAME),
 778              "Incorrect boot loader search path, no java runtime image or " JAVA_BASE_NAME " exploded build");
 779       struct stat st;
 780       if (os::stat(path, &st) == 0) {
 781         // Directory found
 782         Thread* THREAD = Thread::current();
 783         ClassPathEntry* new_entry = create_class_path_entry(path, &st, false, false, CHECK);
 784 
 785         // Check for a jimage
 786         if (Arguments::has_jimage()) {
 787           assert(_jrt_entry == NULL, "should not setup bootstrap class search path twice");
 788           assert(new_entry != NULL && new_entry->is_jrt(), "No java runtime image present");
 789           _jrt_entry = new_entry;
 790           ++_num_entries;
 791 #if INCLUDE_CDS
 792           if (DumpSharedSpaces) {
 793             JImageFile *jimage = _jrt_entry->jimage();
 794             assert(jimage != NULL, "No java runtime image file present");
 795             ClassLoader::initialize_module_loader_map(jimage);
 796           }
 797 #endif
 798         }
 799       } else {
 800         // If path does not exist, exit
 801         vm_exit_during_initialization("Unable to establish the boot loader search path", path);
 802       }
 803       set_base_piece = false;
 804     } else {
 805       // Every entry on the system boot class path after the initial base piece,
 806       // which is set by os::set_boot_path(), is considered an appended entry.
 807       update_class_path_entry_list(path, false, bootstrap_search);
 808     }
 809 
 810 #if INCLUDE_CDS
 811     if (DumpSharedSpaces) {
 812       check_shared_classpath(path);
 813     }
 814 #endif
 815     while (class_path[end] == os::path_separator()[0]) {
 816       end++;
 817     }
 818   }
 819 }
 820 
 821 // During an exploded modules build, each module defined to the boot loader
 822 // will be added to the ClassLoader::_exploded_entries array.
 823 void ClassLoader::add_to_exploded_build_list(Symbol* module_sym, TRAPS) {
 824   assert(!ClassLoader::has_jrt_entry(), "Exploded build not applicable");
 825 
 826   // Set up the boot loader's _exploded_entries list
 827   if (_exploded_entries == NULL) {
 828     _exploded_entries = new (ResourceObj::C_HEAP, mtModule) GrowableArray<ModuleClassPathList*>(EXPLODED_ENTRY_SIZE, true);
 829   }
 830 
 831   // Find the module's symbol
 832   ResourceMark rm(THREAD);
 833   const char *module_name = module_sym->as_C_string();
 834   const char *home = Arguments::get_java_home();
 835   const char file_sep = os::file_separator()[0];
 836   // 10 represents the length of "modules" + 2 file separators + \0
 837   size_t len = strlen(home) + strlen(module_name) + 10;
 838   char *path = NEW_C_HEAP_ARRAY(char, len, mtModule);
 839   jio_snprintf(path, len, "%s%cmodules%c%s", home, file_sep, file_sep, module_name);
 840 
 841   struct stat st;
 842   if (os::stat(path, &st) == 0) {
 843     // Directory found
 844     ClassPathEntry* new_entry = create_class_path_entry(path, &st, false, false, CHECK);
 845 
 846     // If the path specification is valid, enter it into this module's list.
 847     // There is no need to check for duplicate modules in the exploded entry list,
 848     // since no two modules with the same name can be defined to the boot loader.
 849     // This is checked at module definition time in Modules::define_module.
 850     if (new_entry != NULL) {
 851       ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
 852       module_cpl->add_to_list(new_entry);
 853       _exploded_entries->push(module_cpl);
 854       log_info(class, load)("path: %s", path);
 855     }
 856   }
 857   FREE_C_HEAP_ARRAY(char, path);
 858 }
 859 
 860 ClassPathEntry* ClassLoader::create_class_path_entry(const char *path, const struct stat* st,
 861                                                      bool throw_exception,
 862                                                      bool is_boot_append, TRAPS) {
 863   JavaThread* thread = JavaThread::current();
 864   ClassPathEntry* new_entry = NULL;
 865   if ((st->st_mode & S_IFMT) == S_IFREG) {
 866     ResourceMark rm(thread);
 867     // Regular file, should be a zip or jimage file
 868     // Canonicalized filename
 869     char* canonical_path = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, JVM_MAXPATHLEN);
 870     if (!get_canonical_path(path, canonical_path, JVM_MAXPATHLEN)) {
 871       // This matches the classic VM
 872       if (throw_exception) {
 873         THROW_MSG_(vmSymbols::java_io_IOException(), "Bad pathname", NULL);
 874       } else {
 875         return NULL;
 876       }
 877     }
 878     jint error;
 879     JImageFile* jimage =(*JImageOpen)(canonical_path, &error);
 880     if (jimage != NULL) {
 881       new_entry = new ClassPathImageEntry(jimage, canonical_path);
 882     } else {
 883       char* error_msg = NULL;
 884       jzfile* zip;
 885       {
 886         // enable call to C land
 887         ThreadToNativeFromVM ttn(thread);
 888         HandleMark hm(thread);
 889         zip = (*ZipOpen)(canonical_path, &error_msg);
 890       }
 891       if (zip != NULL && error_msg == NULL) {
 892         new_entry = new ClassPathZipEntry(zip, path, is_boot_append);
 893       } else {
 894         char *msg;
 895         if (error_msg == NULL) {
 896           msg = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, strlen(path) + 128); ;
 897           jio_snprintf(msg, strlen(path) + 127, "error in opening JAR file %s", path);
 898         } else {
 899           int len = (int)(strlen(path) + strlen(error_msg) + 128);
 900           msg = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, len); ;
 901           jio_snprintf(msg, len - 1, "error in opening JAR file <%s> %s", error_msg, path);
 902         }
 903         // Don't complain about bad jar files added via -Xbootclasspath/a:.
 904         if (throw_exception && is_init_completed()) {
 905           THROW_MSG_(vmSymbols::java_lang_ClassNotFoundException(), msg, NULL);
 906         } else {
 907           return NULL;
 908         }
 909       }
 910     }
 911     log_info(class, path)("opened: %s", path);
 912     log_info(class, load)("opened: %s", path);
 913   } else {
 914     // Directory
 915     new_entry = new ClassPathDirEntry(path);
 916     log_info(class, load)("path: %s", path);
 917   }
 918   return new_entry;
 919 }
 920 
 921 
 922 // Create a class path zip entry for a given path (return NULL if not found
 923 // or zip/JAR file cannot be opened)
 924 ClassPathZipEntry* ClassLoader::create_class_path_zip_entry(const char *path, bool is_boot_append) {
 925   // check for a regular file
 926   struct stat st;
 927   if (os::stat(path, &st) == 0) {
 928     if ((st.st_mode & S_IFMT) == S_IFREG) {
 929       char canonical_path[JVM_MAXPATHLEN];
 930       if (get_canonical_path(path, canonical_path, JVM_MAXPATHLEN)) {
 931         char* error_msg = NULL;
 932         jzfile* zip;
 933         {
 934           // enable call to C land
 935           JavaThread* thread = JavaThread::current();
 936           ThreadToNativeFromVM ttn(thread);
 937           HandleMark hm(thread);
 938           zip = (*ZipOpen)(canonical_path, &error_msg);
 939         }
 940         if (zip != NULL && error_msg == NULL) {
 941           // create using canonical path
 942           return new ClassPathZipEntry(zip, canonical_path, is_boot_append);
 943         }
 944       }
 945     }
 946   }
 947   return NULL;
 948 }
 949 
 950 // returns true if entry already on class path
 951 bool ClassLoader::contains_append_entry(const char* name) {
 952   ClassPathEntry* e = _first_append_entry;
 953   while (e != NULL) {
 954     // assume zip entries have been canonicalized
 955     if (strcmp(name, e->name()) == 0) {
 956       return true;
 957     }
 958     e = e->next();
 959   }
 960   return false;
 961 }
 962 
 963 void ClassLoader::add_to_list(ClassPathEntry *new_entry) {
 964   if (new_entry != NULL) {
 965     if (_last_append_entry == NULL) {
 966       assert(_first_append_entry == NULL, "boot loader's append class path entry list not empty");
 967       _first_append_entry = _last_append_entry = new_entry;
 968     } else {
 969       _last_append_entry->set_next(new_entry);
 970       _last_append_entry = new_entry;
 971     }
 972   }
 973   _num_entries++;
 974 }
 975 
 976 void ClassLoader::add_to_list(const char *apath) {
 977   update_class_path_entry_list((char*)apath, false, false);
 978 }
 979 
 980 // Returns true IFF the file/dir exists and the entry was successfully created.
 981 bool ClassLoader::update_class_path_entry_list(const char *path,
 982                                                bool check_for_duplicates,
 983                                                bool is_boot_append,
 984                                                bool throw_exception) {
 985   struct stat st;
 986   if (os::stat(path, &st) == 0) {
 987     // File or directory found
 988     ClassPathEntry* new_entry = NULL;
 989     Thread* THREAD = Thread::current();
 990     new_entry = create_class_path_entry(path, &st, throw_exception, is_boot_append, CHECK_(false));
 991     if (new_entry == NULL) {
 992       return false;
 993     }
 994 
 995     // Do not reorder the bootclasspath which would break get_system_package().
 996     // Add new entry to linked list
 997     if (!check_for_duplicates || !contains_append_entry(new_entry->name())) {
 998       ClassLoaderExt::add_class_path_entry(path, check_for_duplicates, new_entry);
 999     }
1000     return true;
1001   } else {
1002 #if INCLUDE_CDS
1003     if (DumpSharedSpaces) {
1004       _shared_paths_misc_info->add_nonexist_path(path);
1005     }
1006 #endif
1007     return false;
1008   }
1009 }
1010 
1011 static void print_module_entry_table(const GrowableArray<ModuleClassPathList*>* const module_list) {
1012   ResourceMark rm;
1013   int num_of_entries = module_list->length();
1014   for (int i = 0; i < num_of_entries; i++) {
1015     ClassPathEntry* e;
1016     ModuleClassPathList* mpl = module_list->at(i);
1017     tty->print("%s=", mpl->module_name()->as_C_string());
1018     e = mpl->module_first_entry();
1019     while (e != NULL) {
1020       tty->print("%s", e->name());
1021       e = e->next();
1022       if (e != NULL) {
1023         tty->print("%s", os::path_separator());
1024       }
1025     }
1026     tty->print(" ;");
1027   }
1028 }
1029 
1030 void ClassLoader::print_bootclasspath() {
1031   ClassPathEntry* e;
1032   tty->print("[bootclasspath= ");
1033 
1034   // Print --patch-module module/path specifications first
1035   if (_patch_mod_entries != NULL) {
1036     print_module_entry_table(_patch_mod_entries);
1037   }
1038 
1039   // [jimage | exploded modules build]
1040   if (has_jrt_entry()) {
1041     // Print the location of the java runtime image
1042     tty->print("%s ;", _jrt_entry->name());
1043   } else {
1044     // Print exploded module build path specifications
1045     if (_exploded_entries != NULL) {
1046       print_module_entry_table(_exploded_entries);
1047     }
1048   }
1049 
1050   // appended entries
1051   e = _first_append_entry;
1052   while (e != NULL) {
1053     tty->print("%s ;", e->name());
1054     e = e->next();
1055   }
1056   tty->print_cr("]");
1057 }
1058 
1059 void ClassLoader::load_zip_library() {
1060   assert(ZipOpen == NULL, "should not load zip library twice");
1061   // First make sure native library is loaded
1062   os::native_java_library();
1063   // Load zip library
1064   char path[JVM_MAXPATHLEN];
1065   char ebuf[1024];
1066   void* handle = NULL;
1067   if (os::dll_build_name(path, sizeof(path), Arguments::get_dll_dir(), "zip")) {
1068     handle = os::dll_load(path, ebuf, sizeof ebuf);
1069   }
1070   if (handle == NULL) {
1071     vm_exit_during_initialization("Unable to load ZIP library", path);
1072   }
1073   // Lookup zip entry points
1074   ZipOpen      = CAST_TO_FN_PTR(ZipOpen_t, os::dll_lookup(handle, "ZIP_Open"));
1075   ZipClose     = CAST_TO_FN_PTR(ZipClose_t, os::dll_lookup(handle, "ZIP_Close"));
1076   FindEntry    = CAST_TO_FN_PTR(FindEntry_t, os::dll_lookup(handle, "ZIP_FindEntry"));
1077   ReadEntry    = CAST_TO_FN_PTR(ReadEntry_t, os::dll_lookup(handle, "ZIP_ReadEntry"));
1078   GetNextEntry = CAST_TO_FN_PTR(GetNextEntry_t, os::dll_lookup(handle, "ZIP_GetNextEntry"));
1079   ZipInflateFully = CAST_TO_FN_PTR(ZipInflateFully_t, os::dll_lookup(handle, "ZIP_InflateFully"));
1080   Crc32        = CAST_TO_FN_PTR(Crc32_t, os::dll_lookup(handle, "ZIP_CRC32"));
1081 
1082   // ZIP_Close is not exported on Windows in JDK5.0 so don't abort if ZIP_Close is NULL
1083   if (ZipOpen == NULL || FindEntry == NULL || ReadEntry == NULL ||
1084       GetNextEntry == NULL || Crc32 == NULL) {
1085     vm_exit_during_initialization("Corrupted ZIP library", path);
1086   }
1087 
1088   if (ZipInflateFully == NULL) {
1089     vm_exit_during_initialization("Corrupted ZIP library ZIP_InflateFully missing", path);
1090   }
1091 
1092   // Lookup canonicalize entry in libjava.dll
1093   void *javalib_handle = os::native_java_library();
1094   CanonicalizeEntry = CAST_TO_FN_PTR(canonicalize_fn_t, os::dll_lookup(javalib_handle, "Canonicalize"));
1095   // This lookup only works on 1.3. Do not check for non-null here
1096 }
1097 
1098 void ClassLoader::load_jimage_library() {
1099   // First make sure native library is loaded
1100   os::native_java_library();
1101   // Load jimage library
1102   char path[JVM_MAXPATHLEN];
1103   char ebuf[1024];
1104   void* handle = NULL;
1105   if (os::dll_build_name(path, sizeof(path), Arguments::get_dll_dir(), "jimage")) {
1106     handle = os::dll_load(path, ebuf, sizeof ebuf);
1107   }
1108   if (handle == NULL) {
1109     vm_exit_during_initialization("Unable to load jimage library", path);
1110   }
1111 
1112   // Lookup jimage entry points
1113   JImageOpen = CAST_TO_FN_PTR(JImageOpen_t, os::dll_lookup(handle, "JIMAGE_Open"));
1114   guarantee(JImageOpen != NULL, "function JIMAGE_Open not found");
1115   JImageClose = CAST_TO_FN_PTR(JImageClose_t, os::dll_lookup(handle, "JIMAGE_Close"));
1116   guarantee(JImageClose != NULL, "function JIMAGE_Close not found");
1117   JImagePackageToModule = CAST_TO_FN_PTR(JImagePackageToModule_t, os::dll_lookup(handle, "JIMAGE_PackageToModule"));
1118   guarantee(JImagePackageToModule != NULL, "function JIMAGE_PackageToModule not found");
1119   JImageFindResource = CAST_TO_FN_PTR(JImageFindResource_t, os::dll_lookup(handle, "JIMAGE_FindResource"));
1120   guarantee(JImageFindResource != NULL, "function JIMAGE_FindResource not found");
1121   JImageGetResource = CAST_TO_FN_PTR(JImageGetResource_t, os::dll_lookup(handle, "JIMAGE_GetResource"));
1122   guarantee(JImageGetResource != NULL, "function JIMAGE_GetResource not found");
1123   JImageResourceIterator = CAST_TO_FN_PTR(JImageResourceIterator_t, os::dll_lookup(handle, "JIMAGE_ResourceIterator"));
1124   guarantee(JImageResourceIterator != NULL, "function JIMAGE_ResourceIterator not found");
1125   JImageResourcePath = CAST_TO_FN_PTR(JImage_ResourcePath_t, os::dll_lookup(handle, "JIMAGE_ResourcePath"));
1126   guarantee(JImageResourcePath != NULL, "function JIMAGE_ResourcePath not found");
1127 }
1128 
1129 jboolean ClassLoader::decompress(void *in, u8 inSize, void *out, u8 outSize, char **pmsg) {
1130   return (*ZipInflateFully)(in, inSize, out, outSize, pmsg);
1131 }
1132 
1133 int ClassLoader::crc32(int crc, const char* buf, int len) {
1134   assert(Crc32 != NULL, "ZIP_CRC32 is not found");
1135   return (*Crc32)(crc, (const jbyte*)buf, len);
1136 }
1137 
1138 #if INCLUDE_CDS
1139 void ClassLoader::initialize_module_loader_map(JImageFile* jimage) {
1140   if (!DumpSharedSpaces) {
1141     return; // only needed for CDS dump time
1142   }
1143 
1144   ResourceMark rm;
1145   jlong size;
1146   JImageLocationRef location = (*JImageFindResource)(jimage, JAVA_BASE_NAME, get_jimage_version_string(), MODULE_LOADER_MAP, &size);
1147   if (location == 0) {
1148     vm_exit_during_initialization(
1149       "Cannot find ModuleLoaderMap location from modules jimage.", NULL);
1150   }
1151   char* buffer = NEW_RESOURCE_ARRAY(char, size + 1);
1152   buffer[size] = '\0';
1153   jlong read = (*JImageGetResource)(jimage, location, buffer, size);
1154   if (read != size) {
1155     vm_exit_during_initialization(
1156       "Cannot find ModuleLoaderMap resource from modules jimage.", NULL);
1157   }
1158   char* char_buf = (char*)buffer;
1159   int buflen = (int)strlen(char_buf);
1160   char* begin_ptr = char_buf;
1161   char* end_ptr = strchr(begin_ptr, '\n');
1162   bool process_boot_modules = false;
1163   _boot_modules_array = new (ResourceObj::C_HEAP, mtModule)
1164     GrowableArray<char*>(INITIAL_BOOT_MODULES_ARRAY_SIZE, true);
1165   _platform_modules_array = new (ResourceObj::C_HEAP, mtModule)
1166     GrowableArray<char*>(INITIAL_PLATFORM_MODULES_ARRAY_SIZE, true);
1167   while (end_ptr != NULL && (end_ptr - char_buf) < buflen) {
1168     // Allocate a buffer from the C heap to be appended to the _boot_modules_array
1169     // or the _platform_modules_array.
1170     char* temp_name = NEW_C_HEAP_ARRAY(char, (size_t)(end_ptr - begin_ptr + 1), mtInternal);
1171     strncpy(temp_name, begin_ptr, end_ptr - begin_ptr);
1172     temp_name[end_ptr - begin_ptr] = '\0';
1173     if (strncmp(temp_name, "BOOT", 4) == 0) {
1174       process_boot_modules = true;
1175       FREE_C_HEAP_ARRAY(char, temp_name);
1176     } else if (strncmp(temp_name, "PLATFORM", 8) == 0) {
1177       process_boot_modules = false;
1178       FREE_C_HEAP_ARRAY(char, temp_name);
1179     } else {
1180       // module name
1181       if (process_boot_modules) {
1182         _boot_modules_array->append(temp_name);
1183       } else {
1184         _platform_modules_array->append(temp_name);
1185       }
1186     }
1187     begin_ptr = ++end_ptr;
1188     end_ptr = strchr(begin_ptr, '\n');
1189   }
1190 }
1191 #endif
1192 
1193 // Function add_package extracts the package from the fully qualified class name
1194 // and checks if the package is in the boot loader's package entry table.  If so,
1195 // then it sets the classpath_index in the package entry record.
1196 //
1197 // The classpath_index field is used to find the entry on the boot loader class
1198 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
1199 // in an unnamed module.  It is also used to indicate (for all packages whose
1200 // classes are loaded by the boot loader) that at least one of the package's
1201 // classes has been loaded.
1202 bool ClassLoader::add_package(const char *fullq_class_name, s2 classpath_index, TRAPS) {
1203   assert(fullq_class_name != NULL, "just checking");
1204 
1205   // Get package name from fully qualified class name.
1206   ResourceMark rm;
1207   const char *cp = package_from_name(fullq_class_name);
1208   if (cp != NULL) {
1209     PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();
1210     TempNewSymbol pkg_symbol = SymbolTable::new_symbol(cp, CHECK_false);
1211     PackageEntry* pkg_entry = pkg_entry_tbl->lookup_only(pkg_symbol);
1212     if (pkg_entry != NULL) {
1213       assert(classpath_index != -1, "Unexpected classpath_index");
1214       pkg_entry->set_classpath_index(classpath_index);
1215     } else {
1216       return false;
1217     }
1218   }
1219   return true;
1220 }
1221 
1222 oop ClassLoader::get_system_package(const char* name, TRAPS) {
1223   // Look up the name in the boot loader's package entry table.
1224   if (name != NULL) {
1225     TempNewSymbol package_sym = SymbolTable::new_symbol(name, (int)strlen(name), CHECK_NULL);
1226     // Look for the package entry in the boot loader's package entry table.
1227     PackageEntry* package =
1228       ClassLoaderData::the_null_class_loader_data()->packages()->lookup_only(package_sym);
1229 
1230     // Return NULL if package does not exist or if no classes in that package
1231     // have been loaded.
1232     if (package != NULL && package->has_loaded_class()) {
1233       ModuleEntry* module = package->module();
1234       if (module->location() != NULL) {
1235         ResourceMark rm(THREAD);
1236         Handle ml = java_lang_String::create_from_str(
1237           module->location()->as_C_string(), THREAD);
1238         return ml();
1239       }
1240       // Return entry on boot loader class path.
1241       Handle cph = java_lang_String::create_from_str(
1242         ClassLoader::classpath_entry(package->classpath_index())->name(), THREAD);
1243       return cph();
1244     }
1245   }
1246   return NULL;
1247 }
1248 
1249 objArrayOop ClassLoader::get_system_packages(TRAPS) {
1250   ResourceMark rm(THREAD);
1251   // List of pointers to PackageEntrys that have loaded classes.
1252   GrowableArray<PackageEntry*>* loaded_class_pkgs = new GrowableArray<PackageEntry*>(50);
1253   {
1254     MutexLocker ml(Module_lock, THREAD);
1255 
1256     PackageEntryTable* pe_table =
1257       ClassLoaderData::the_null_class_loader_data()->packages();
1258 
1259     // Collect the packages that have at least one loaded class.
1260     for (int x = 0; x < pe_table->table_size(); x++) {
1261       for (PackageEntry* package_entry = pe_table->bucket(x);
1262            package_entry != NULL;
1263            package_entry = package_entry->next()) {
1264         if (package_entry->has_loaded_class()) {
1265           loaded_class_pkgs->append(package_entry);
1266         }
1267       }
1268     }
1269   }
1270 
1271 
1272   // Allocate objArray and fill with java.lang.String
1273   objArrayOop r = oopFactory::new_objArray(SystemDictionary::String_klass(),
1274                                            loaded_class_pkgs->length(), CHECK_NULL);
1275   objArrayHandle result(THREAD, r);
1276   for (int x = 0; x < loaded_class_pkgs->length(); x++) {
1277     PackageEntry* package_entry = loaded_class_pkgs->at(x);
1278     Handle str = java_lang_String::create_from_symbol(package_entry->name(), CHECK_NULL);
1279     result->obj_at_put(x, str());
1280   }
1281   return result();
1282 }
1283 
1284 #if INCLUDE_CDS
1285 s2 ClassLoader::module_to_classloader(const char* module_name) {
1286 
1287   assert(DumpSharedSpaces, "dump time only");
1288   assert(_boot_modules_array != NULL, "_boot_modules_array is NULL");
1289   assert(_platform_modules_array != NULL, "_platform_modules_array is NULL");
1290 
1291   int array_size = _boot_modules_array->length();
1292   for (int i = 0; i < array_size; i++) {
1293     if (strcmp(module_name, _boot_modules_array->at(i)) == 0) {
1294       return BOOT_LOADER;
1295     }
1296   }
1297 
1298   array_size = _platform_modules_array->length();
1299   for (int i = 0; i < array_size; i++) {
1300     if (strcmp(module_name, _platform_modules_array->at(i)) == 0) {
1301       return PLATFORM_LOADER;
1302     }
1303   }
1304 
1305   return APP_LOADER;
1306 }
1307 
1308 s2 ClassLoader::classloader_type(Symbol* class_name, ClassPathEntry* e, int classpath_index, TRAPS) {
1309   assert(DumpSharedSpaces, "Only used for CDS dump time");
1310 
1311   // obtain the classloader type based on the class name.
1312   // First obtain the package name based on the class name. Then obtain
1313   // the classloader type based on the package name from the jimage using
1314   // a jimage API. If the classloader type cannot be found from the
1315   // jimage, it is determined by the class path entry.
1316   jshort loader_type = ClassLoader::APP_LOADER;
1317   if (e->is_jrt()) {
1318     ResourceMark rm;
1319     TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK_0);
1320     if (pkg_name != NULL) {
1321       const char* pkg_name_C_string = (const char*)(pkg_name->as_C_string());
1322       ClassPathImageEntry* cpie = (ClassPathImageEntry*)e;
1323       JImageFile* jimage = cpie->jimage();
1324       char* module_name = (char*)(*JImagePackageToModule)(jimage, pkg_name_C_string);
1325       if (module_name != NULL) {
1326         loader_type = ClassLoader::module_to_classloader(module_name);
1327       }
1328     }
1329   } else if (ClassLoaderExt::is_boot_classpath(classpath_index)) {
1330     loader_type = ClassLoader::BOOT_LOADER;
1331   }
1332   return loader_type;
1333 }
1334 #endif
1335 
1336 // caller needs ResourceMark
1337 const char* ClassLoader::file_name_for_class_name(const char* class_name,
1338                                                   int class_name_len) {
1339   assert(class_name != NULL, "invariant");
1340   assert((int)strlen(class_name) == class_name_len, "invariant");
1341 
1342   static const char class_suffix[] = ".class";
1343 
1344   char* const file_name = NEW_RESOURCE_ARRAY(char,
1345                                              class_name_len +
1346                                              sizeof(class_suffix)); // includes term NULL
1347 
1348   strncpy(file_name, class_name, class_name_len);
1349   strncpy(&file_name[class_name_len], class_suffix, sizeof(class_suffix));
1350 
1351   return file_name;
1352 }
1353 
1354 // Search either the patch-module or exploded build entries for class
1355 ClassFileStream* ClassLoader::search_module_entries(const GrowableArray<ModuleClassPathList*>* const module_list,
1356                                                     const char* const class_name, const char* const file_name, TRAPS) {
1357   ClassFileStream* stream = NULL;
1358 
1359   // Find the class' defining module in the boot loader's module entry table
1360   PackageEntry* pkg_entry = get_package_entry(class_name, ClassLoaderData::the_null_class_loader_data(), CHECK_NULL);
1361   ModuleEntry* mod_entry = (pkg_entry != NULL) ? pkg_entry->module() : NULL;
1362 
1363   // If the module system has not defined java.base yet, then
1364   // classes loaded are assumed to be defined to java.base.
1365   // When java.base is eventually defined by the module system,
1366   // all packages of classes that have been previously loaded
1367   // are verified in ModuleEntryTable::verify_javabase_packages().
1368   if (!Universe::is_module_initialized() &&
1369       !ModuleEntryTable::javabase_defined() &&
1370       mod_entry == NULL) {
1371     mod_entry = ModuleEntryTable::javabase_moduleEntry();
1372   }
1373 
1374   // The module must be a named module
1375   if (mod_entry != NULL && mod_entry->is_named()) {
1376     int num_of_entries = module_list->length();
1377     const Symbol* class_module_name = mod_entry->name();
1378 
1379     // Loop through all the modules in either the patch-module or exploded entries looking for module
1380     for (int i = 0; i < num_of_entries; i++) {
1381       ModuleClassPathList* module_cpl = module_list->at(i);
1382       Symbol* module_cpl_name = module_cpl->module_name();
1383 
1384       if (module_cpl_name->fast_compare(class_module_name) == 0) {
1385         // Class' module has been located, attempt to load
1386         // the class from the module's ClassPathEntry list.
1387         ClassPathEntry* e = module_cpl->module_first_entry();
1388         while (e != NULL) {
1389           stream = e->open_stream(file_name, CHECK_NULL);
1390           // No context.check is required since CDS is not supported
1391           // for an exploded modules build or if --patch-module is specified.
1392           if (NULL != stream) {
1393             return stream;
1394           }
1395           e = e->next();
1396         }
1397         // If the module was located, break out even if the class was not
1398         // located successfully from that module's ClassPathEntry list.
1399         // There will not be another valid entry for that module.
1400         return NULL;
1401       }
1402     }
1403   }
1404 
1405   return NULL;
1406 }
1407 
1408 InstanceKlass* ClassLoader::load_class(Symbol* name, bool search_append_only, TRAPS) {
1409   assert(name != NULL, "invariant");
1410   assert(THREAD->is_Java_thread(), "must be a JavaThread");
1411 
1412   ResourceMark rm(THREAD);
1413   HandleMark hm(THREAD);
1414 
1415   const char* const class_name = name->as_C_string();
1416 
1417   EventMark m("loading class %s", class_name);
1418   ThreadProfilerMark tpm(ThreadProfilerMark::classLoaderRegion);
1419 
1420   const char* const file_name = file_name_for_class_name(class_name,
1421                                                          name->utf8_length());
1422   assert(file_name != NULL, "invariant");
1423 
1424   ClassLoaderExt::Context context(class_name, file_name, THREAD);
1425 
1426   // Lookup stream for parsing .class file
1427   ClassFileStream* stream = NULL;
1428   s2 classpath_index = 0;
1429   ClassPathEntry* e = NULL;
1430 
1431   // If DumpSharedSpaces is true boot loader visibility boundaries are set to:
1432   //   - [jimage] + [_first_append_entry to _last_append_entry] (all path entries).
1433   //
1434   // If search_append_only is true, boot loader visibility boundaries are
1435   // set to be _first_append_entry to the end. This includes:
1436   //   [-Xbootclasspath/a]; [jvmti appended entries]
1437   //
1438   // If both DumpSharedSpaces and search_append_only are false, boot loader
1439   // visibility boundaries are set to be the --patch-module entries plus the base piece.
1440   // This would include:
1441   //   [--patch-module=<module>=<file>(<pathsep><file>)*]; [jimage | exploded module build]
1442   //
1443   // DumpSharedSpaces and search_append_only are mutually exclusive and cannot
1444   // be true at the same time.
1445   assert(!(DumpSharedSpaces && search_append_only), "DumpSharedSpaces and search_append_only are both true");
1446 
1447   // Load Attempt #1: --patch-module
1448   // Determine the class' defining module.  If it appears in the _patch_mod_entries,
1449   // attempt to load the class from those locations specific to the module.
1450   // Specifications to --patch-module can contain a partial number of classes
1451   // that are part of the overall module definition.  So if a particular class is not
1452   // found within its module specification, the search should continue to Load Attempt #2.
1453   // Note: The --patch-module entries are never searched if the boot loader's
1454   //       visibility boundary is limited to only searching the append entries.
1455   if (_patch_mod_entries != NULL && !search_append_only) {
1456     // At CDS dump time, the --patch-module entries are ignored. That means a
1457     // class is still loaded from the runtime image even if it might
1458     // appear in the _patch_mod_entries. The runtime shared class visibility
1459     // check will determine if a shared class is visible based on the runtime
1460     // environemnt, including the runtime --patch-module setting.
1461     if (!DumpSharedSpaces) {
1462       stream = search_module_entries(_patch_mod_entries, class_name, file_name, CHECK_NULL);
1463     }
1464   }
1465 
1466   // Load Attempt #2: [jimage | exploded build]
1467   if (!search_append_only && (NULL == stream)) {
1468     if (has_jrt_entry()) {
1469       e = _jrt_entry;
1470       stream = _jrt_entry->open_stream(file_name, CHECK_NULL);
1471       if (!context.check(stream, classpath_index)) {
1472         return NULL;
1473       }
1474     } else {
1475       // Exploded build - attempt to locate class in its defining module's location.
1476       assert(_exploded_entries != NULL, "No exploded build entries present");
1477       stream = search_module_entries(_exploded_entries, class_name, file_name, CHECK_NULL);
1478     }
1479   }
1480 
1481   // Load Attempt #3: [-Xbootclasspath/a]; [jvmti appended entries]
1482   if ((search_append_only || DumpSharedSpaces) && (NULL == stream)) {
1483     // For the boot loader append path search, the starting classpath_index
1484     // for the appended piece is always 1 to account for either the
1485     // _jrt_entry or the _exploded_entries.
1486     assert(classpath_index == 0, "The classpath_index has been incremented incorrectly");
1487     classpath_index = 1;
1488 
1489     e = _first_append_entry;
1490     while (e != NULL) {
1491       stream = e->open_stream(file_name, CHECK_NULL);
1492       if (!context.check(stream, classpath_index)) {
1493         return NULL;
1494       }
1495       if (NULL != stream) {
1496         break;
1497       }
1498       e = e->next();
1499       ++classpath_index;
1500     }
1501   }
1502 
1503   if (NULL == stream) {
1504     if (DumpSharedSpaces) {
1505       tty->print_cr("Preload Warning: Cannot find %s", class_name);
1506     }
1507     return NULL;
1508   }
1509 
1510   stream->set_verify(context.should_verify(classpath_index));
1511 
1512   ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
1513   Handle protection_domain;
1514 
1515   InstanceKlass* result = KlassFactory::create_from_stream(stream,
1516                                                            name,
1517                                                            loader_data,
1518                                                            protection_domain,
1519                                                            NULL, // host_klass
1520                                                            NULL, // cp_patches
1521                                                            THREAD);
1522   if (HAS_PENDING_EXCEPTION) {
1523     if (DumpSharedSpaces) {
1524       tty->print_cr("Preload Error: Failed to load %s", class_name);
1525     }
1526     return NULL;
1527   }
1528 
1529   return context.record_result(name, e, classpath_index, result, THREAD);
1530 }
1531 
1532 // Initialize the class loader's access to methods in libzip.  Parse and
1533 // process the boot classpath into a list ClassPathEntry objects.  Once
1534 // this list has been created, it must not change order (see class PackageInfo)
1535 // it can be appended to and is by jvmti and the kernel vm.
1536 
1537 void ClassLoader::initialize() {
1538   EXCEPTION_MARK;
1539 
1540   if (UsePerfData) {
1541     // jvmstat performance counters
1542     NEWPERFTICKCOUNTER(_perf_accumulated_time, SUN_CLS, "time");
1543     NEWPERFTICKCOUNTER(_perf_class_init_time, SUN_CLS, "classInitTime");
1544     NEWPERFTICKCOUNTER(_perf_class_init_selftime, SUN_CLS, "classInitTime.self");
1545     NEWPERFTICKCOUNTER(_perf_class_verify_time, SUN_CLS, "classVerifyTime");
1546     NEWPERFTICKCOUNTER(_perf_class_verify_selftime, SUN_CLS, "classVerifyTime.self");
1547     NEWPERFTICKCOUNTER(_perf_class_link_time, SUN_CLS, "classLinkedTime");
1548     NEWPERFTICKCOUNTER(_perf_class_link_selftime, SUN_CLS, "classLinkedTime.self");
1549     NEWPERFEVENTCOUNTER(_perf_classes_inited, SUN_CLS, "initializedClasses");
1550     NEWPERFEVENTCOUNTER(_perf_classes_linked, SUN_CLS, "linkedClasses");
1551     NEWPERFEVENTCOUNTER(_perf_classes_verified, SUN_CLS, "verifiedClasses");
1552 
1553     NEWPERFTICKCOUNTER(_perf_class_parse_time, SUN_CLS, "parseClassTime");
1554     NEWPERFTICKCOUNTER(_perf_class_parse_selftime, SUN_CLS, "parseClassTime.self");
1555     NEWPERFTICKCOUNTER(_perf_sys_class_lookup_time, SUN_CLS, "lookupSysClassTime");
1556     NEWPERFTICKCOUNTER(_perf_shared_classload_time, SUN_CLS, "sharedClassLoadTime");
1557     NEWPERFTICKCOUNTER(_perf_sys_classload_time, SUN_CLS, "sysClassLoadTime");
1558     NEWPERFTICKCOUNTER(_perf_app_classload_time, SUN_CLS, "appClassLoadTime");
1559     NEWPERFTICKCOUNTER(_perf_app_classload_selftime, SUN_CLS, "appClassLoadTime.self");
1560     NEWPERFEVENTCOUNTER(_perf_app_classload_count, SUN_CLS, "appClassLoadCount");
1561     NEWPERFTICKCOUNTER(_perf_define_appclasses, SUN_CLS, "defineAppClasses");
1562     NEWPERFTICKCOUNTER(_perf_define_appclass_time, SUN_CLS, "defineAppClassTime");
1563     NEWPERFTICKCOUNTER(_perf_define_appclass_selftime, SUN_CLS, "defineAppClassTime.self");
1564     NEWPERFBYTECOUNTER(_perf_app_classfile_bytes_read, SUN_CLS, "appClassBytes");
1565     NEWPERFBYTECOUNTER(_perf_sys_classfile_bytes_read, SUN_CLS, "sysClassBytes");
1566 
1567 
1568     // The following performance counters are added for measuring the impact
1569     // of the bug fix of 6365597. They are mainly focused on finding out
1570     // the behavior of system & user-defined classloader lock, whether
1571     // ClassLoader.loadClass/findClass is being called synchronized or not.
1572     // Also two additional counters are created to see whether 'UnsyncloadClass'
1573     // flag is being set or not and how many times load_instance_class call
1574     // fails with linkageError etc.
1575     NEWPERFEVENTCOUNTER(_sync_systemLoaderLockContentionRate, SUN_CLS,
1576                         "systemLoaderLockContentionRate");
1577     NEWPERFEVENTCOUNTER(_sync_nonSystemLoaderLockContentionRate, SUN_CLS,
1578                         "nonSystemLoaderLockContentionRate");
1579     NEWPERFEVENTCOUNTER(_sync_JVMFindLoadedClassLockFreeCounter, SUN_CLS,
1580                         "jvmFindLoadedClassNoLockCalls");
1581     NEWPERFEVENTCOUNTER(_sync_JVMDefineClassLockFreeCounter, SUN_CLS,
1582                         "jvmDefineClassNoLockCalls");
1583 
1584     NEWPERFEVENTCOUNTER(_sync_JNIDefineClassLockFreeCounter, SUN_CLS,
1585                         "jniDefineClassNoLockCalls");
1586 
1587     NEWPERFEVENTCOUNTER(_unsafe_defineClassCallCounter, SUN_CLS,
1588                         "unsafeDefineClassCalls");
1589 
1590     NEWPERFEVENTCOUNTER(_isUnsyncloadClass, SUN_CLS, "isUnsyncloadClassSet");
1591     NEWPERFEVENTCOUNTER(_load_instance_class_failCounter, SUN_CLS,
1592                         "loadInstanceClassFailRate");
1593 
1594     // increment the isUnsyncloadClass counter if UnsyncloadClass is set.
1595     if (UnsyncloadClass) {
1596       _isUnsyncloadClass->inc();
1597     }
1598   }
1599 
1600   // lookup zip library entry points
1601   load_zip_library();
1602   // lookup jimage library entry points
1603   load_jimage_library();
1604 #if INCLUDE_CDS
1605   // initialize search path
1606   if (DumpSharedSpaces) {
1607     _shared_paths_misc_info = SharedClassUtil::allocate_shared_paths_misc_info();
1608   }
1609 #endif
1610   setup_bootstrap_search_path();
1611 }
1612 
1613 #if INCLUDE_CDS
1614 void ClassLoader::initialize_shared_path() {
1615   if (DumpSharedSpaces) {
1616     ClassLoaderExt::setup_search_paths();
1617     _shared_paths_misc_info->write_jint(0); // see comments in SharedPathsMiscInfo::check()
1618   }
1619 }
1620 #endif
1621 
1622 jlong ClassLoader::classloader_time_ms() {
1623   return UsePerfData ?
1624     Management::ticks_to_ms(_perf_accumulated_time->get_value()) : -1;
1625 }
1626 
1627 jlong ClassLoader::class_init_count() {
1628   return UsePerfData ? _perf_classes_inited->get_value() : -1;
1629 }
1630 
1631 jlong ClassLoader::class_init_time_ms() {
1632   return UsePerfData ?
1633     Management::ticks_to_ms(_perf_class_init_time->get_value()) : -1;
1634 }
1635 
1636 jlong ClassLoader::class_verify_time_ms() {
1637   return UsePerfData ?
1638     Management::ticks_to_ms(_perf_class_verify_time->get_value()) : -1;
1639 }
1640 
1641 jlong ClassLoader::class_link_count() {
1642   return UsePerfData ? _perf_classes_linked->get_value() : -1;
1643 }
1644 
1645 jlong ClassLoader::class_link_time_ms() {
1646   return UsePerfData ?
1647     Management::ticks_to_ms(_perf_class_link_time->get_value()) : -1;
1648 }
1649 
1650 int ClassLoader::compute_Object_vtable() {
1651   // hardwired for JDK1.2 -- would need to duplicate class file parsing
1652   // code to determine actual value from file
1653   // Would be value '11' if finals were in vtable
1654   int JDK_1_2_Object_vtable_size = 5;
1655   return JDK_1_2_Object_vtable_size * vtableEntry::size();
1656 }
1657 
1658 
1659 void classLoader_init1() {
1660   ClassLoader::initialize();
1661 }
1662 
1663 // Complete the ClassPathEntry setup for the boot loader
1664 void ClassLoader::classLoader_init2(TRAPS) {
1665   // Setup the list of module/path pairs for --patch-module processing
1666   // This must be done after the SymbolTable is created in order
1667   // to use fast_compare on module names instead of a string compare.
1668   if (Arguments::get_patch_mod_prefix() != NULL) {
1669     setup_patch_mod_entries();
1670   }
1671 
1672   // Create the ModuleEntry for java.base (must occur after setup_patch_mod_entries
1673   // to successfully determine if java.base has been patched)
1674   create_javabase();
1675 
1676   // Setup the initial java.base/path pair for the exploded build entries.
1677   // As more modules are defined during module system initialization, more
1678   // entries will be added to the exploded build array.
1679   if (!has_jrt_entry()) {
1680     assert(!DumpSharedSpaces, "DumpSharedSpaces not supported with exploded module builds");
1681     assert(!UseSharedSpaces, "UsedSharedSpaces not supported with exploded module builds");
1682     add_to_exploded_build_list(vmSymbols::java_base(), CHECK);
1683   }
1684 }
1685 
1686 
1687 bool ClassLoader::get_canonical_path(const char* orig, char* out, int len) {
1688   assert(orig != NULL && out != NULL && len > 0, "bad arguments");
1689   if (CanonicalizeEntry != NULL) {
1690     JavaThread* THREAD = JavaThread::current();
1691     JNIEnv* env = THREAD->jni_environment();
1692     ResourceMark rm(THREAD);
1693 
1694     // os::native_path writes into orig_copy
1695     char* orig_copy = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, strlen(orig)+1);
1696     strcpy(orig_copy, orig);
1697     if ((CanonicalizeEntry)(env, os::native_path(orig_copy), out, len) < 0) {
1698       return false;
1699     }
1700   } else {
1701     // On JDK 1.2.2 the Canonicalize does not exist, so just do nothing
1702     strncpy(out, orig, len);
1703     out[len - 1] = '\0';
1704   }
1705   return true;
1706 }
1707 
1708 void ClassLoader::create_javabase() {
1709   Thread* THREAD = Thread::current();
1710 
1711   // Create java.base's module entry for the boot
1712   // class loader prior to loading j.l.Ojbect.
1713   ClassLoaderData* null_cld = ClassLoaderData::the_null_class_loader_data();
1714 
1715   // Get module entry table
1716   ModuleEntryTable* null_cld_modules = null_cld->modules();
1717   if (null_cld_modules == NULL) {
1718     vm_exit_during_initialization("No ModuleEntryTable for the boot class loader");
1719   }
1720 
1721   {
1722     MutexLocker ml(Module_lock, THREAD);
1723     ModuleEntry* jb_module = null_cld_modules->locked_create_entry_or_null(Handle(),
1724                                false, vmSymbols::java_base(), NULL, NULL, null_cld);
1725     if (jb_module == NULL) {
1726       vm_exit_during_initialization("Unable to create ModuleEntry for " JAVA_BASE_NAME);
1727     }
1728     ModuleEntryTable::set_javabase_moduleEntry(jb_module);
1729   }
1730 }
1731 
1732 #ifndef PRODUCT
1733 
1734 // CompileTheWorld
1735 //
1736 // Iterates over all class path entries and forces compilation of all methods
1737 // in all classes found. Currently, only zip/jar archives are searched.
1738 //
1739 // The classes are loaded by the Java level bootstrap class loader, and the
1740 // initializer is called. If DelayCompilationDuringStartup is true (default),
1741 // the interpreter will run the initialization code. Note that forcing
1742 // initialization in this way could potentially lead to initialization order
1743 // problems, in which case we could just force the initialization bit to be set.
1744 
1745 
1746 // We need to iterate over the contents of a zip/jar file, so we replicate the
1747 // jzcell and jzfile definitions from zip_util.h but rename jzfile to real_jzfile,
1748 // since jzfile already has a void* definition.
1749 //
1750 // Note that this is only used in debug mode.
1751 //
1752 // HotSpot integration note:
1753 // Matches zip_util.h 1.14 99/06/01 from jdk1.3 beta H build
1754 
1755 
1756 // JDK 1.3 version
1757 typedef struct real_jzentry {         /* Zip file entry */
1758     char *name;                 /* entry name */
1759     jint time;                  /* modification time */
1760     jint size;                  /* size of uncompressed data */
1761     jint csize;                 /* size of compressed data (zero if uncompressed) */
1762     jint crc;                   /* crc of uncompressed data */
1763     char *comment;              /* optional zip file comment */
1764     jbyte *extra;               /* optional extra data */
1765     jint pos;                   /* position of LOC header (if negative) or data */
1766 } real_jzentry;
1767 
1768 typedef struct real_jzfile {  /* Zip file */
1769     char *name;                 /* zip file name */
1770     jint refs;                  /* number of active references */
1771     jint fd;                    /* open file descriptor */
1772     void *lock;                 /* read lock */
1773     char *comment;              /* zip file comment */
1774     char *msg;                  /* zip error message */
1775     void *entries;              /* array of hash cells */
1776     jint total;                 /* total number of entries */
1777     unsigned short *table;      /* Hash chain heads: indexes into entries */
1778     jint tablelen;              /* number of hash eads */
1779     real_jzfile *next;        /* next zip file in search list */
1780     jzentry *cache;             /* we cache the most recently freed jzentry */
1781     /* Information on metadata names in META-INF directory */
1782     char **metanames;           /* array of meta names (may have null names) */
1783     jint metacount;             /* number of slots in metanames array */
1784     /* If there are any per-entry comments, they are in the comments array */
1785     char **comments;
1786 } real_jzfile;
1787 
1788 void ClassPathDirEntry::compile_the_world(Handle loader, TRAPS) {
1789   // For now we only compile all methods in all classes in zip/jar files
1790   tty->print_cr("CompileTheWorld : Skipped classes in %s", _dir);
1791   tty->cr();
1792 }
1793 
1794 void ClassPathZipEntry::compile_the_world(Handle loader, TRAPS) {
1795   real_jzfile* zip = (real_jzfile*) _zip;
1796   tty->print_cr("CompileTheWorld : Compiling all classes in %s", zip->name);
1797   tty->cr();
1798   // Iterate over all entries in zip file
1799   for (int n = 0; ; n++) {
1800     real_jzentry * ze = (real_jzentry *)((*GetNextEntry)(_zip, n));
1801     if (ze == NULL) break;
1802     ClassLoader::compile_the_world_in(ze->name, loader, CHECK);
1803   }
1804   if (HAS_PENDING_EXCEPTION) {
1805     if (PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())) {
1806       CLEAR_PENDING_EXCEPTION;
1807       tty->print_cr("\nCompileTheWorld : Ran out of memory\n");
1808       tty->print_cr("Increase class metadata storage if a limit was set");
1809     } else {
1810       tty->print_cr("\nCompileTheWorld : Unexpected exception occurred\n");
1811     }
1812   }
1813 }
1814 
1815 void ClassLoader::compile_the_world() {
1816   EXCEPTION_MARK;
1817   HandleMark hm(THREAD);
1818   ResourceMark rm(THREAD);
1819 
1820   assert(has_jrt_entry(), "Compile The World not supported with exploded module build");
1821 
1822   // Find bootstrap loader
1823   Handle system_class_loader (THREAD, SystemDictionary::java_system_loader());
1824   jlong start = os::javaTimeMillis();
1825 
1826   // Compile the world for the modular java runtime image
1827   _jrt_entry->compile_the_world(system_class_loader, CATCH);
1828 
1829   // Iterate over all bootstrap class path appended entries
1830   ClassPathEntry* e = _first_append_entry;
1831   while (e != NULL) {
1832     assert(!e->is_jrt(), "A modular java runtime image is present on the list of appended entries");
1833     e->compile_the_world(system_class_loader, CATCH);
1834     e = e->next();
1835   }
1836   jlong end = os::javaTimeMillis();
1837   tty->print_cr("CompileTheWorld : Done (%d classes, %d methods, " JLONG_FORMAT " ms)",
1838                 _compile_the_world_class_counter, _compile_the_world_method_counter, (end - start));
1839   {
1840     // Print statistics as if before normal exit:
1841     extern void print_statistics();
1842     print_statistics();
1843   }
1844   vm_exit(0);
1845 }
1846 
1847 int ClassLoader::_compile_the_world_class_counter = 0;
1848 int ClassLoader::_compile_the_world_method_counter = 0;
1849 static int _codecache_sweep_counter = 0;
1850 
1851 // Filter out all exceptions except OOMs
1852 static void clear_pending_exception_if_not_oom(TRAPS) {
1853   if (HAS_PENDING_EXCEPTION &&
1854       !PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())) {
1855     CLEAR_PENDING_EXCEPTION;
1856   }
1857   // The CHECK at the caller will propagate the exception out
1858 }
1859 
1860 /**
1861  * Returns if the given method should be compiled when doing compile-the-world.
1862  *
1863  * TODO:  This should be a private method in a CompileTheWorld class.
1864  */
1865 static bool can_be_compiled(methodHandle m, int comp_level) {
1866   assert(CompileTheWorld, "must be");
1867 
1868   // It's not valid to compile a native wrapper for MethodHandle methods
1869   // that take a MemberName appendix since the bytecode signature is not
1870   // correct.
1871   vmIntrinsics::ID iid = m->intrinsic_id();
1872   if (MethodHandles::is_signature_polymorphic(iid) && MethodHandles::has_member_arg(iid)) {
1873     return false;
1874   }
1875 
1876   // Don't compile methods in __Value if value types are disabled
1877   if (!EnableMVT && !EnableValhalla && m->method_holder()->name() == vmSymbols::java_lang____Value()) {
1878     return false;
1879   }
1880 
1881   return CompilationPolicy::can_be_compiled(m, comp_level);
1882 }
1883 
1884 void ClassLoader::compile_the_world_in(char* name, Handle loader, TRAPS) {
1885   if (string_ends_with(name, ".class")) {
1886     // We have a .class file
1887     int len = (int)strlen(name);
1888     char buffer[2048];
1889     strncpy(buffer, name, len - 6);
1890     buffer[len-6] = 0;
1891     // If the file has a period after removing .class, it's not really a
1892     // valid class file.  The class loader will check everything else.
1893     if (strchr(buffer, '.') == NULL) {
1894       _compile_the_world_class_counter++;
1895       if (_compile_the_world_class_counter > CompileTheWorldStopAt) return;
1896 
1897       // Construct name without extension
1898       TempNewSymbol sym = SymbolTable::new_symbol(buffer, CHECK);
1899       // Use loader to load and initialize class
1900       Klass* k = SystemDictionary::resolve_or_null(sym, loader, Handle(), THREAD);
1901       if (k != NULL && !HAS_PENDING_EXCEPTION) {
1902         k->initialize(THREAD);
1903       }
1904       bool exception_occurred = HAS_PENDING_EXCEPTION;
1905       clear_pending_exception_if_not_oom(CHECK);
1906       if (CompileTheWorldPreloadClasses && k != NULL) {
1907         InstanceKlass* ik = InstanceKlass::cast(k);
1908         ConstantPool::preload_and_initialize_all_classes(ik->constants(), THREAD);
1909         if (HAS_PENDING_EXCEPTION) {
1910           // If something went wrong in preloading we just ignore it
1911           clear_pending_exception_if_not_oom(CHECK);
1912           tty->print_cr("Preloading failed for (%d) %s", _compile_the_world_class_counter, buffer);
1913         }
1914       }
1915 
1916       if (_compile_the_world_class_counter >= CompileTheWorldStartAt) {
1917         if (k == NULL || exception_occurred) {
1918           // If something went wrong (e.g. ExceptionInInitializerError) we skip this class
1919           tty->print_cr("CompileTheWorld (%d) : Skipping %s", _compile_the_world_class_counter, buffer);
1920         } else {
1921           tty->print_cr("CompileTheWorld (%d) : %s", _compile_the_world_class_counter, buffer);
1922           // Preload all classes to get around uncommon traps
1923           // Iterate over all methods in class
1924           int comp_level = CompilationPolicy::policy()->initial_compile_level();
1925           InstanceKlass* ik = InstanceKlass::cast(k);
1926           for (int n = 0; n < ik->methods()->length(); n++) {
1927             methodHandle m (THREAD, ik->methods()->at(n));
1928             if (can_be_compiled(m, comp_level)) {
1929               if (++_codecache_sweep_counter == CompileTheWorldSafepointInterval) {
1930                 // Give sweeper a chance to keep up with CTW
1931                 VM_ForceSafepoint op;
1932                 VMThread::execute(&op);
1933                 _codecache_sweep_counter = 0;
1934               }
1935               // Force compilation
1936               CompileBroker::compile_method(m, InvocationEntryBci, comp_level,
1937                                             methodHandle(), 0, CompileTask::Reason_CTW, THREAD);
1938               if (HAS_PENDING_EXCEPTION) {
1939                 clear_pending_exception_if_not_oom(CHECK);
1940                 tty->print_cr("CompileTheWorld (%d) : Skipping method: %s", _compile_the_world_class_counter, m->name_and_sig_as_C_string());
1941               } else {
1942                 _compile_the_world_method_counter++;
1943               }
1944               if (TieredCompilation && TieredStopAtLevel >= CompLevel_full_optimization) {
1945                 // Clobber the first compile and force second tier compilation
1946                 CompiledMethod* nm = m->code();
1947                 if (nm != NULL && !m->is_method_handle_intrinsic()) {
1948                   // Throw out the code so that the code cache doesn't fill up
1949                   nm->make_not_entrant();
1950                 }
1951                 CompileBroker::compile_method(m, InvocationEntryBci, CompLevel_full_optimization,
1952                                               methodHandle(), 0, CompileTask::Reason_CTW, THREAD);
1953                 if (HAS_PENDING_EXCEPTION) {
1954                   clear_pending_exception_if_not_oom(CHECK);
1955                   tty->print_cr("CompileTheWorld (%d) : Skipping method: %s", _compile_the_world_class_counter, m->name_and_sig_as_C_string());
1956                 } else {
1957                   _compile_the_world_method_counter++;
1958                 }
1959               }
1960             } else {
1961               tty->print_cr("CompileTheWorld (%d) : Skipping method: %s", _compile_the_world_class_counter, m->name_and_sig_as_C_string());
1962             }
1963 
1964             CompiledMethod* nm = m->code();
1965             if (nm != NULL && !m->is_method_handle_intrinsic()) {
1966               // Throw out the code so that the code cache doesn't fill up
1967               nm->make_not_entrant();
1968             }
1969           }
1970         }
1971       }
1972     }
1973   }
1974 }
1975 
1976 #endif //PRODUCT
1977 
1978 // Please keep following two functions at end of this file. With them placed at top or in middle of the file,
1979 // they could get inlined by agressive compiler, an unknown trick, see bug 6966589.
1980 void PerfClassTraceTime::initialize() {
1981   if (!UsePerfData) return;
1982 
1983   if (_eventp != NULL) {
1984     // increment the event counter
1985     _eventp->inc();
1986   }
1987 
1988   // stop the current active thread-local timer to measure inclusive time
1989   _prev_active_event = -1;
1990   for (int i=0; i < EVENT_TYPE_COUNT; i++) {
1991      if (_timers[i].is_active()) {
1992        assert(_prev_active_event == -1, "should have only one active timer");
1993        _prev_active_event = i;
1994        _timers[i].stop();
1995      }
1996   }
1997 
1998   if (_recursion_counters == NULL || (_recursion_counters[_event_type])++ == 0) {
1999     // start the inclusive timer if not recursively called
2000     _t.start();
2001   }
2002 
2003   // start thread-local timer of the given event type
2004    if (!_timers[_event_type].is_active()) {
2005     _timers[_event_type].start();
2006   }
2007 }
2008 
2009 PerfClassTraceTime::~PerfClassTraceTime() {
2010   if (!UsePerfData) return;
2011 
2012   // stop the thread-local timer as the event completes
2013   // and resume the thread-local timer of the event next on the stack
2014   _timers[_event_type].stop();
2015   jlong selftime = _timers[_event_type].ticks();
2016 
2017   if (_prev_active_event >= 0) {
2018     _timers[_prev_active_event].start();
2019   }
2020 
2021   if (_recursion_counters != NULL && --(_recursion_counters[_event_type]) > 0) return;
2022 
2023   // increment the counters only on the leaf call
2024   _t.stop();
2025   _timep->inc(_t.ticks());
2026   if (_selftimep != NULL) {
2027     _selftimep->inc(selftime);
2028   }
2029   // add all class loading related event selftime to the accumulated time counter
2030   ClassLoader::perf_accumulated_time()->inc(selftime);
2031 
2032   // reset the timer
2033   _timers[_event_type].reset();
2034 }