1 /*
   2  * Copyright (c) 1997, 2018, 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/systemDictionary.hpp"
  38 #include "classfile/vmSymbols.hpp"
  39 #include "compiler/compileBroker.hpp"
  40 #include "interpreter/bytecodeStream.hpp"
  41 #include "interpreter/oopMapCache.hpp"
  42 #include "logging/log.hpp"
  43 #include "logging/logStream.hpp"
  44 #include "logging/logTag.hpp"
  45 #include "memory/allocation.inline.hpp"
  46 #include "memory/filemap.hpp"
  47 #include "memory/oopFactory.hpp"
  48 #include "memory/resourceArea.hpp"
  49 #include "memory/universe.hpp"
  50 #include "oops/instanceKlass.hpp"
  51 #include "oops/instanceRefKlass.hpp"
  52 #include "oops/method.inline.hpp"
  53 #include "oops/objArrayOop.inline.hpp"
  54 #include "oops/oop.inline.hpp"
  55 #include "oops/symbol.hpp"
  56 #include "prims/jvm_misc.hpp"
  57 #include "runtime/arguments.hpp"
  58 #include "runtime/compilationPolicy.hpp"
  59 #include "runtime/handles.hpp"
  60 #include "runtime/handles.inline.hpp"
  61 #include "runtime/init.hpp"
  62 #include "runtime/interfaceSupport.inline.hpp"
  63 #include "runtime/java.hpp"
  64 #include "runtime/javaCalls.hpp"
  65 #include "runtime/os.inline.hpp"
  66 #include "runtime/threadCritical.hpp"
  67 #include "runtime/timer.hpp"
  68 #include "runtime/vm_version.hpp"
  69 #include "services/management.hpp"
  70 #include "services/threadService.hpp"
  71 #include "utilities/events.hpp"
  72 #include "utilities/hashtable.inline.hpp"
  73 #include "utilities/macros.hpp"
  74 #if INCLUDE_CDS
  75 #include "classfile/sharedPathsMiscInfo.hpp"
  76 #endif
  77 
  78 // Entry points in zip.dll for loading zip/jar file entries
  79 
  80 typedef void * * (*ZipOpen_t)(const char *name, char **pmsg);
  81 typedef void (*ZipClose_t)(jzfile *zip);
  82 typedef jzentry* (*FindEntry_t)(jzfile *zip, const char *name, jint *sizeP, jint *nameLen);
  83 typedef jboolean (*ReadEntry_t)(jzfile *zip, jzentry *entry, unsigned char *buf, char *namebuf);
  84 typedef jzentry* (*GetNextEntry_t)(jzfile *zip, jint n);
  85 typedef jboolean (*ZipInflateFully_t)(void *inBuf, jlong inLen, void *outBuf, jlong outLen, char **pmsg);
  86 typedef jint     (*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::_load_instance_class_failCounter = NULL;
 139 
 140 GrowableArray<ModuleClassPathList*>* ClassLoader::_patch_mod_entries = NULL;
 141 GrowableArray<ModuleClassPathList*>* ClassLoader::_exploded_entries = NULL;
 142 ClassPathEntry* ClassLoader::_jrt_entry = NULL;
 143 ClassPathEntry* ClassLoader::_first_append_entry = NULL;
 144 ClassPathEntry* ClassLoader::_last_append_entry  = NULL;
 145 #if INCLUDE_CDS
 146 ClassPathEntry* ClassLoader::_app_classpath_entries = NULL;
 147 ClassPathEntry* ClassLoader::_last_app_classpath_entry = NULL;
 148 ClassPathEntry* ClassLoader::_module_path_entries = NULL;
 149 ClassPathEntry* ClassLoader::_last_module_path_entry = 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') {
 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 PackageEntry* ClassLoader::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   assert((_dir != NULL) && (name != NULL), "sanity");
 263   size_t path_len = strlen(_dir) + strlen(name) + strlen(os::file_separator()) + 1;
 264   char* path = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, path_len);
 265   int len = jio_snprintf(path, path_len, "%s%s%s", _dir, os::file_separator(), name);
 266   assert(len == (int)(path_len - 1), "sanity");
 267   // check if file exists
 268   struct stat st;
 269   if (os::stat(path, &st) == 0) {
 270     // found file, open it
 271     int file_handle = os::open(path, 0, 0);
 272     if (file_handle != -1) {
 273       // read contents into resource array
 274       u1* buffer = NEW_RESOURCE_ARRAY(u1, st.st_size);
 275       size_t num_read = os::read(file_handle, (char*) buffer, st.st_size);
 276       // close file
 277       os::close(file_handle);
 278       // construct ClassFileStream
 279       if (num_read == (size_t)st.st_size) {
 280         if (UsePerfData) {
 281           ClassLoader::perf_sys_classfile_bytes_read()->inc(num_read);
 282         }
 283         FREE_RESOURCE_ARRAY(char, path, path_len);
 284         // Resource allocated
 285         return new ClassFileStream(buffer,
 286                                    st.st_size,
 287                                    _dir,
 288                                    ClassFileStream::verify);
 289       }
 290     }
 291   }
 292   FREE_RESOURCE_ARRAY(char, path, path_len);
 293   return NULL;
 294 }
 295 
 296 ClassPathZipEntry::ClassPathZipEntry(jzfile* zip, const char* zip_name, bool is_boot_append) : ClassPathEntry() {
 297   _zip = zip;
 298   char *copy = NEW_C_HEAP_ARRAY(char, strlen(zip_name)+1, mtClass);
 299   strcpy(copy, zip_name);
 300   _zip_name = copy;
 301   _is_boot_append = is_boot_append;
 302   _multi_versioned = _unknown;
 303 }
 304 
 305 ClassPathZipEntry::~ClassPathZipEntry() {
 306   if (ZipClose != NULL) {
 307     (*ZipClose)(_zip);
 308   }
 309   FREE_C_HEAP_ARRAY(char, _zip_name);
 310 }
 311 
 312 u1* ClassPathZipEntry::open_entry(const char* name, jint* filesize, bool nul_terminate, TRAPS) {
 313     // enable call to C land
 314   JavaThread* thread = JavaThread::current();
 315   ThreadToNativeFromVM ttn(thread);
 316   // check whether zip archive contains name
 317   jint name_len;
 318   jzentry* entry = (*FindEntry)(_zip, name, filesize, &name_len);
 319   if (entry == NULL) return NULL;
 320   u1* buffer;
 321   char name_buf[128];
 322   char* filename;
 323   if (name_len < 128) {
 324     filename = name_buf;
 325   } else {
 326     filename = NEW_RESOURCE_ARRAY(char, name_len + 1);
 327   }
 328 
 329   // read contents into resource array
 330   int size = (*filesize) + ((nul_terminate) ? 1 : 0);
 331   buffer = NEW_RESOURCE_ARRAY(u1, size);
 332   if (!(*ReadEntry)(_zip, entry, buffer, filename)) return NULL;
 333 
 334   // return result
 335   if (nul_terminate) {
 336     buffer[*filesize] = 0;
 337   }
 338   return buffer;
 339 }
 340 
 341 #if INCLUDE_CDS
 342 u1* ClassPathZipEntry::open_versioned_entry(const char* name, jint* filesize, TRAPS) {
 343   u1* buffer = NULL;
 344   if (DumpSharedSpaces && !_is_boot_append) {
 345     // We presume default is multi-release enabled
 346     const char* multi_ver = Arguments::get_property("jdk.util.jar.enableMultiRelease");
 347     const char* verstr = Arguments::get_property("jdk.util.jar.version");
 348     bool is_multi_ver = (multi_ver == NULL ||
 349                          strcmp(multi_ver, "true") == 0 ||
 350                          strcmp(multi_ver, "force")  == 0) &&
 351                          is_multiple_versioned(THREAD);
 352     // command line version setting
 353     int version = 0;
 354     const int base_version = 8; // JDK8
 355     int cur_ver = JDK_Version::current().major_version();
 356     if (verstr != NULL) {
 357       version = atoi(verstr);
 358       if (version < base_version || version > cur_ver) {
 359         // If the specified version is lower than the base version, the base
 360         // entry will be used; if the version is higher than the current
 361         // jdk version, the highest versioned entry will be used.
 362         if (version < base_version) {
 363           is_multi_ver = false;
 364         }
 365         // print out warning, do not use assertion here since it will continue to look
 366         // for proper version.
 367         warning("JDK%d is not supported in multiple version jars", version);
 368       }
 369     }
 370 
 371     if (is_multi_ver) {
 372       int n;
 373       const char* version_entry = "META-INF/versions/";
 374       // 10 is the max length of a decimal 32-bit non-negative number
 375       // 2 includes the '/' and trailing zero
 376       size_t entry_name_len = strlen(version_entry) + 10 + strlen(name) + 2;
 377       char* entry_name = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, entry_name_len);
 378       if (version > 0) {
 379         n = jio_snprintf(entry_name, entry_name_len, "%s%d/%s", version_entry, version, name);
 380         entry_name[n] = '\0';
 381         buffer = open_entry((const char*)entry_name, filesize, false, CHECK_NULL);
 382         if (buffer == NULL) {
 383           warning("Could not find %s in %s, try to find highest version instead", entry_name, _zip_name);
 384         }
 385       }
 386       if (buffer == NULL) {
 387         for (int i = cur_ver; i >= base_version; i--) {
 388           n = jio_snprintf(entry_name, entry_name_len, "%s%d/%s", version_entry, i, name);
 389           entry_name[n] = '\0';
 390           buffer = open_entry((const char*)entry_name, filesize, false, CHECK_NULL);
 391           if (buffer != NULL) {
 392             break;
 393           }
 394         }
 395       }
 396       FREE_RESOURCE_ARRAY(char, entry_name, entry_name_len);
 397     }
 398   }
 399   return buffer;
 400 }
 401 
 402 bool ClassPathZipEntry::is_multiple_versioned(TRAPS) {
 403   assert(DumpSharedSpaces, "called only at dump time");
 404   if (_multi_versioned != _unknown) {
 405     return (_multi_versioned == _yes) ? true : false;
 406   }
 407   jint size;
 408   char* buffer = (char*)open_entry("META-INF/MANIFEST.MF", &size, true, CHECK_false);
 409   if (buffer != NULL) {
 410     char* p = buffer;
 411     for ( ; *p; ++p) *p = tolower(*p);
 412     if (strstr(buffer, "multi-release: true") != NULL) {
 413       _multi_versioned = _yes;
 414       return true;
 415     }
 416   }
 417   _multi_versioned = _no;
 418   return false;
 419 }
 420 #endif // INCLUDE_CDS
 421 
 422 ClassFileStream* ClassPathZipEntry::open_stream(const char* name, TRAPS) {
 423   jint filesize;
 424   u1* buffer = open_versioned_entry(name, &filesize, CHECK_NULL);
 425   if (buffer == NULL) {
 426     buffer = open_entry(name, &filesize, false, CHECK_NULL);
 427     if (buffer == NULL) {
 428       return NULL;
 429     }
 430   }
 431   if (UsePerfData) {
 432     ClassLoader::perf_sys_classfile_bytes_read()->inc(filesize);
 433   }
 434   // Resource allocated
 435   return new ClassFileStream(buffer,
 436                              filesize,
 437                              _zip_name,
 438                              ClassFileStream::verify);
 439 }
 440 
 441 // invoke function for each entry in the zip file
 442 void ClassPathZipEntry::contents_do(void f(const char* name, void* context), void* context) {
 443   JavaThread* thread = JavaThread::current();
 444   HandleMark  handle_mark(thread);
 445   ThreadToNativeFromVM ttn(thread);
 446   for (int n = 0; ; n++) {
 447     jzentry * ze = ((*GetNextEntry)(_zip, n));
 448     if (ze == NULL) break;
 449     (*f)(ze->name, context);
 450   }
 451 }
 452 
 453 ClassPathImageEntry::ClassPathImageEntry(JImageFile* jimage, const char* name) :
 454   ClassPathEntry(),
 455   _jimage(jimage) {
 456   guarantee(jimage != NULL, "jimage file is null");
 457   guarantee(name != NULL, "jimage file name is null");
 458   size_t len = strlen(name) + 1;
 459   _name = NEW_C_HEAP_ARRAY(const char, len, mtClass);
 460   strncpy((char *)_name, name, len);
 461 }
 462 
 463 ClassPathImageEntry::~ClassPathImageEntry() {
 464   if (_name != NULL) {
 465     FREE_C_HEAP_ARRAY(const char, _name);
 466     _name = NULL;
 467   }
 468   if (_jimage != NULL) {
 469     (*JImageClose)(_jimage);
 470     _jimage = NULL;
 471   }
 472 }
 473 
 474 // For a class in a named module, look it up in the jimage file using this syntax:
 475 //    /<module-name>/<package-name>/<base-class>
 476 //
 477 // Assumptions:
 478 //     1. There are no unnamed modules in the jimage file.
 479 //     2. A package is in at most one module in the jimage file.
 480 //
 481 ClassFileStream* ClassPathImageEntry::open_stream(const char* name, TRAPS) {
 482   jlong size;
 483   JImageLocationRef location = (*JImageFindResource)(_jimage, "", get_jimage_version_string(), name, &size);
 484 
 485   if (location == 0) {
 486     ResourceMark rm;
 487     const char* pkg_name = ClassLoader::package_from_name(name);
 488 
 489     if (pkg_name != NULL) {
 490       if (!Universe::is_module_initialized()) {
 491         location = (*JImageFindResource)(_jimage, JAVA_BASE_NAME, get_jimage_version_string(), name, &size);
 492 #if INCLUDE_CDS
 493         // CDS uses the boot class loader to load classes whose packages are in
 494         // modules defined for other class loaders.  So, for now, get their module
 495         // names from the "modules" jimage file.
 496         if (DumpSharedSpaces && location == 0) {
 497           const char* module_name = (*JImagePackageToModule)(_jimage, pkg_name);
 498           if (module_name != NULL) {
 499             location = (*JImageFindResource)(_jimage, module_name, get_jimage_version_string(), name, &size);
 500           }
 501         }
 502 #endif
 503 
 504       } else {
 505         PackageEntry* package_entry = ClassLoader::get_package_entry(name, ClassLoaderData::the_null_class_loader_data(), CHECK_NULL);
 506         if (package_entry != NULL) {
 507           ResourceMark rm;
 508           // Get the module name
 509           ModuleEntry* module = package_entry->module();
 510           assert(module != NULL, "Boot classLoader package missing module");
 511           assert(module->is_named(), "Boot classLoader package is in unnamed module");
 512           const char* module_name = module->name()->as_C_string();
 513           if (module_name != NULL) {
 514             location = (*JImageFindResource)(_jimage, module_name, get_jimage_version_string(), name, &size);
 515           }
 516         }
 517       }
 518     }
 519   }
 520   if (location != 0) {
 521     if (UsePerfData) {
 522       ClassLoader::perf_sys_classfile_bytes_read()->inc(size);
 523     }
 524     char* data = NEW_RESOURCE_ARRAY(char, size);
 525     (*JImageGetResource)(_jimage, location, data, size);
 526     // Resource allocated
 527     return new ClassFileStream((u1*)data,
 528                                (int)size,
 529                                _name,
 530                                ClassFileStream::verify);
 531   }
 532 
 533   return NULL;
 534 }
 535 
 536 JImageLocationRef ClassLoader::jimage_find_resource(JImageFile* jf,
 537                                                     const char* module_name,
 538                                                     const char* file_name,
 539                                                     jlong &size) {
 540   return ((*JImageFindResource)(jf, module_name, get_jimage_version_string(), file_name, &size));
 541 }
 542 
 543 #ifndef PRODUCT
 544 bool ctw_visitor(JImageFile* jimage,
 545         const char* module_name, const char* version, const char* package,
 546         const char* name, const char* extension, void* arg) {
 547   if (strcmp(extension, "class") == 0) {
 548     Thread* THREAD = Thread::current();
 549     ResourceMark rm(THREAD);
 550     char* path = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, JIMAGE_MAX_PATH);
 551     jio_snprintf(path, JIMAGE_MAX_PATH - 1, "%s/%s.class", package, name);
 552     ClassLoader::compile_the_world_in(path, *(Handle*)arg, THREAD);
 553     return !HAS_PENDING_EXCEPTION;
 554   }
 555   return true;
 556 }
 557 
 558 void ClassPathImageEntry::compile_the_world(Handle loader, TRAPS) {
 559   tty->print_cr("CompileTheWorld : Compiling all classes in %s", name());
 560   tty->cr();
 561   (*JImageResourceIterator)(_jimage, (JImageResourceVisitor_t)ctw_visitor, (void *)&loader);
 562   if (HAS_PENDING_EXCEPTION) {
 563     if (PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())) {
 564       CLEAR_PENDING_EXCEPTION;
 565       tty->print_cr("\nCompileTheWorld : Ran out of memory\n");
 566       tty->print_cr("Increase class metadata storage if a limit was set");
 567     } else {
 568       tty->print_cr("\nCompileTheWorld : Unexpected exception occurred\n");
 569     }
 570   }
 571 }
 572 #endif
 573 
 574 bool ClassPathImageEntry::is_modules_image() const {
 575   return ClassLoader::is_modules_image(name());
 576 }
 577 
 578 #if INCLUDE_CDS
 579 void ClassLoader::exit_with_path_failure(const char* error, const char* message) {
 580   assert(DumpSharedSpaces, "only called at dump time");
 581   tty->print_cr("Hint: enable -Xlog:class+path=info to diagnose the failure");
 582   vm_exit_during_initialization(error, message);
 583 }
 584 #endif
 585 
 586 ModuleClassPathList::ModuleClassPathList(Symbol* module_name) {
 587   _module_name = module_name;
 588   _module_first_entry = NULL;
 589   _module_last_entry = NULL;
 590 }
 591 
 592 ModuleClassPathList::~ModuleClassPathList() {
 593   // Clean out each ClassPathEntry on list
 594   ClassPathEntry* e = _module_first_entry;
 595   while (e != NULL) {
 596     ClassPathEntry* next_entry = e->next();
 597     delete e;
 598     e = next_entry;
 599   }
 600 }
 601 
 602 void ModuleClassPathList::add_to_list(ClassPathEntry* new_entry) {
 603   if (new_entry != NULL) {
 604     if (_module_last_entry == NULL) {
 605       _module_first_entry = _module_last_entry = new_entry;
 606     } else {
 607       _module_last_entry->set_next(new_entry);
 608       _module_last_entry = new_entry;
 609     }
 610   }
 611 }
 612 
 613 void ClassLoader::trace_class_path(const char* msg, const char* name) {
 614   LogTarget(Info, class, path) lt;
 615   if (lt.is_enabled()) {
 616     LogStream ls(lt);
 617     if (msg) {
 618       ls.print("%s", msg);
 619     }
 620     if (name) {
 621       if (strlen(name) < 256) {
 622         ls.print("%s", name);
 623       } else {
 624         // For very long paths, we need to print each character separately,
 625         // as print_cr() has a length limit
 626         while (name[0] != '\0') {
 627           ls.print("%c", name[0]);
 628           name++;
 629         }
 630       }
 631     }
 632     ls.cr();
 633   }
 634 }
 635 
 636 void ClassLoader::setup_bootstrap_search_path() {
 637   const char* sys_class_path = Arguments::get_sysclasspath();
 638   if (PrintSharedArchiveAndExit) {
 639     // Don't print sys_class_path - this is the bootcp of this current VM process, not necessarily
 640     // the same as the bootcp of the shared archive.
 641   } else {
 642     trace_class_path("bootstrap loader class path=", sys_class_path);
 643   }
 644 #if INCLUDE_CDS
 645   if (DumpSharedSpaces) {
 646     _shared_paths_misc_info->add_boot_classpath(sys_class_path);
 647   }
 648 #endif
 649   setup_boot_search_path(sys_class_path);
 650 }
 651 
 652 #if INCLUDE_CDS
 653 int ClassLoader::get_shared_paths_misc_info_size() {
 654   return _shared_paths_misc_info->get_used_bytes();
 655 }
 656 
 657 void* ClassLoader::get_shared_paths_misc_info() {
 658   return _shared_paths_misc_info->buffer();
 659 }
 660 
 661 bool ClassLoader::check_shared_paths_misc_info(void *buf, int size) {
 662   SharedPathsMiscInfo* checker = new SharedPathsMiscInfo((char*)buf, size);
 663   bool result = checker->check();
 664   delete checker;
 665   return result;
 666 }
 667 
 668 void ClassLoader::setup_app_search_path(const char *class_path) {
 669 
 670   assert(DumpSharedSpaces, "Sanity");
 671 
 672   Thread* THREAD = Thread::current();
 673   int len = (int)strlen(class_path);
 674   int end = 0;
 675 
 676   // Iterate over class path entries
 677   for (int start = 0; start < len; start = end) {
 678     while (class_path[end] && class_path[end] != os::path_separator()[0]) {
 679       end++;
 680     }
 681     EXCEPTION_MARK;
 682     ResourceMark rm(THREAD);
 683     char* path = NEW_RESOURCE_ARRAY(char, end - start + 1);
 684     strncpy(path, &class_path[start], end - start);
 685     path[end - start] = '\0';
 686 
 687     update_class_path_entry_list(path, false, false);
 688 
 689     while (class_path[end] == os::path_separator()[0]) {
 690       end++;
 691     }
 692   }
 693 }
 694 
 695 void ClassLoader::add_to_module_path_entries(const char* path,
 696                                              ClassPathEntry* entry) {
 697   assert(entry != NULL, "ClassPathEntry should not be NULL");
 698   assert(DumpSharedSpaces, "dump time only");
 699 
 700   // The entry does not exist, add to the list
 701   if (_module_path_entries == NULL) {
 702     assert(_last_module_path_entry == NULL, "Sanity");
 703     _module_path_entries = _last_module_path_entry = entry;
 704   } else {
 705     _last_module_path_entry->set_next(entry);
 706     _last_module_path_entry = entry;
 707   }
 708 }
 709 
 710 // Add a module path to the _module_path_entries list.
 711 void ClassLoader::update_module_path_entry_list(const char *path, TRAPS) {
 712   assert(DumpSharedSpaces, "dump time only");
 713   struct stat st;
 714   int ret = os::stat(path, &st);
 715   assert(ret == 0, "module path must exist");
 716   // File or directory found
 717   ClassPathEntry* new_entry = NULL;
 718   new_entry = create_class_path_entry(path, &st, true /* throw_exception */,
 719                                       false /*is_boot_append */, CHECK);
 720   if (new_entry == NULL) {
 721     return;
 722   }
 723 
 724   add_to_module_path_entries(path, new_entry);
 725   return;
 726 }
 727 
 728 void ClassLoader::setup_module_search_path(const char* path, TRAPS) {
 729   update_module_path_entry_list(path, THREAD);
 730 }
 731 #endif // INCLUDE_CDS
 732 
 733 // Construct the array of module/path pairs as specified to --patch-module
 734 // for the boot loader to search ahead of the jimage, if the class being
 735 // loaded is defined to a module that has been specified to --patch-module.
 736 void ClassLoader::setup_patch_mod_entries() {
 737   Thread* THREAD = Thread::current();
 738   GrowableArray<ModulePatchPath*>* patch_mod_args = Arguments::get_patch_mod_prefix();
 739   int num_of_entries = patch_mod_args->length();
 740 
 741 
 742   // Set up the boot loader's _patch_mod_entries list
 743   _patch_mod_entries = new (ResourceObj::C_HEAP, mtModule) GrowableArray<ModuleClassPathList*>(num_of_entries, true);
 744 
 745   for (int i = 0; i < num_of_entries; i++) {
 746     const char* module_name = (patch_mod_args->at(i))->module_name();
 747     Symbol* const module_sym = SymbolTable::lookup(module_name, (int)strlen(module_name), CHECK);
 748     assert(module_sym != NULL, "Failed to obtain Symbol for module name");
 749     ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
 750 
 751     char* class_path = (patch_mod_args->at(i))->path_string();
 752     int len = (int)strlen(class_path);
 753     int end = 0;
 754     // Iterate over the module's class path entries
 755     for (int start = 0; start < len; start = end) {
 756       while (class_path[end] && class_path[end] != os::path_separator()[0]) {
 757         end++;
 758       }
 759       EXCEPTION_MARK;
 760       ResourceMark rm(THREAD);
 761       char* path = NEW_RESOURCE_ARRAY(char, end - start + 1);
 762       strncpy(path, &class_path[start], end - start);
 763       path[end - start] = '\0';
 764 
 765       struct stat st;
 766       if (os::stat(path, &st) == 0) {
 767         // File or directory found
 768         ClassPathEntry* new_entry = create_class_path_entry(path, &st, false, false, CHECK);
 769         // If the path specification is valid, enter it into this module's list
 770         if (new_entry != NULL) {
 771           module_cpl->add_to_list(new_entry);
 772         }
 773       }
 774 
 775       while (class_path[end] == os::path_separator()[0]) {
 776         end++;
 777       }
 778     }
 779 
 780     // Record the module into the list of --patch-module entries only if
 781     // valid ClassPathEntrys have been created
 782     if (module_cpl->module_first_entry() != NULL) {
 783       _patch_mod_entries->push(module_cpl);
 784     }
 785   }
 786 }
 787 
 788 // Determine whether the module has been patched via the command-line
 789 // option --patch-module
 790 bool ClassLoader::is_in_patch_mod_entries(Symbol* module_name) {
 791   if (_patch_mod_entries != NULL && _patch_mod_entries->is_nonempty()) {
 792     int table_len = _patch_mod_entries->length();
 793     for (int i = 0; i < table_len; i++) {
 794       ModuleClassPathList* patch_mod = _patch_mod_entries->at(i);
 795       if (module_name->fast_compare(patch_mod->module_name()) == 0) {
 796         return true;
 797       }
 798     }
 799   }
 800   return false;
 801 }
 802 
 803 // Set up the _jrt_entry if present and boot append path
 804 void ClassLoader::setup_boot_search_path(const char *class_path) {
 805   int len = (int)strlen(class_path);
 806   int end = 0;
 807   bool set_base_piece = true;
 808 
 809 #if INCLUDE_CDS
 810   if (DumpSharedSpaces) {
 811     if (!Arguments::has_jimage()) {
 812       vm_exit_during_initialization("CDS is not supported in exploded JDK build", NULL);
 813     }
 814   }
 815 #endif
 816 
 817   // Iterate over class path entries
 818   for (int start = 0; start < len; start = end) {
 819     while (class_path[end] && class_path[end] != os::path_separator()[0]) {
 820       end++;
 821     }
 822     EXCEPTION_MARK;
 823     ResourceMark rm(THREAD);
 824     char* path = NEW_RESOURCE_ARRAY(char, end - start + 1);
 825     strncpy(path, &class_path[start], end - start);
 826     path[end - start] = '\0';
 827 
 828     if (set_base_piece) {
 829       // The first time through the bootstrap_search setup, it must be determined
 830       // what the base or core piece of the boot loader search is.  Either a java runtime
 831       // image is present or this is an exploded module build situation.
 832       assert(string_ends_with(path, MODULES_IMAGE_NAME) || string_ends_with(path, JAVA_BASE_NAME),
 833              "Incorrect boot loader search path, no java runtime image or " JAVA_BASE_NAME " exploded build");
 834       struct stat st;
 835       if (os::stat(path, &st) == 0) {
 836         // Directory found
 837         ClassPathEntry* new_entry = create_class_path_entry(path, &st, false, false, CHECK);
 838 
 839         // Check for a jimage
 840         if (Arguments::has_jimage()) {
 841           assert(_jrt_entry == NULL, "should not setup bootstrap class search path twice");
 842           assert(new_entry != NULL && new_entry->is_modules_image(), "No java runtime image present");
 843           _jrt_entry = new_entry;
 844           assert(_jrt_entry->jimage() != NULL, "No java runtime image");
 845         }
 846       } else {
 847         // If path does not exist, exit
 848         vm_exit_during_initialization("Unable to establish the boot loader search path", path);
 849       }
 850       set_base_piece = false;
 851     } else {
 852       // Every entry on the system boot class path after the initial base piece,
 853       // which is set by os::set_boot_path(), is considered an appended entry.
 854       update_class_path_entry_list(path, false, true);
 855     }
 856 
 857     while (class_path[end] == os::path_separator()[0]) {
 858       end++;
 859     }
 860   }
 861 }
 862 
 863 // During an exploded modules build, each module defined to the boot loader
 864 // will be added to the ClassLoader::_exploded_entries array.
 865 void ClassLoader::add_to_exploded_build_list(Symbol* module_sym, TRAPS) {
 866   assert(!ClassLoader::has_jrt_entry(), "Exploded build not applicable");
 867   assert(_exploded_entries != NULL, "_exploded_entries was not initialized");
 868 
 869   // Find the module's symbol
 870   ResourceMark rm(THREAD);
 871   const char *module_name = module_sym->as_C_string();
 872   const char *home = Arguments::get_java_home();
 873   const char file_sep = os::file_separator()[0];
 874   // 10 represents the length of "modules" + 2 file separators + \0
 875   size_t len = strlen(home) + strlen(module_name) + 10;
 876   char *path = NEW_RESOURCE_ARRAY(char, len);
 877   jio_snprintf(path, len, "%s%cmodules%c%s", home, file_sep, file_sep, module_name);
 878 
 879   struct stat st;
 880   if (os::stat(path, &st) == 0) {
 881     // Directory found
 882     ClassPathEntry* new_entry = create_class_path_entry(path, &st, false, false, CHECK);
 883 
 884     // If the path specification is valid, enter it into this module's list.
 885     // There is no need to check for duplicate modules in the exploded entry list,
 886     // since no two modules with the same name can be defined to the boot loader.
 887     // This is checked at module definition time in Modules::define_module.
 888     if (new_entry != NULL) {
 889       ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
 890       module_cpl->add_to_list(new_entry);
 891       {
 892         MutexLocker ml(Module_lock, THREAD);
 893         _exploded_entries->push(module_cpl);
 894       }
 895       log_info(class, load)("path: %s", path);
 896     }
 897   }
 898 }
 899 
 900 ClassPathEntry* ClassLoader::create_class_path_entry(const char *path, const struct stat* st,
 901                                                      bool throw_exception,
 902                                                      bool is_boot_append, TRAPS) {
 903   JavaThread* thread = JavaThread::current();
 904   ClassPathEntry* new_entry = NULL;
 905   if ((st->st_mode & S_IFMT) == S_IFREG) {
 906     ResourceMark rm(thread);
 907     // Regular file, should be a zip or jimage file
 908     // Canonicalized filename
 909     char* canonical_path = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, JVM_MAXPATHLEN);
 910     if (!get_canonical_path(path, canonical_path, JVM_MAXPATHLEN)) {
 911       // This matches the classic VM
 912       if (throw_exception) {
 913         THROW_MSG_(vmSymbols::java_io_IOException(), "Bad pathname", NULL);
 914       } else {
 915         return NULL;
 916       }
 917     }
 918     jint error;
 919     JImageFile* jimage =(*JImageOpen)(canonical_path, &error);
 920     if (jimage != NULL) {
 921       new_entry = new ClassPathImageEntry(jimage, canonical_path);
 922     } else {
 923       char* error_msg = NULL;
 924       jzfile* zip;
 925       {
 926         // enable call to C land
 927         ThreadToNativeFromVM ttn(thread);
 928         HandleMark hm(thread);
 929         zip = (*ZipOpen)(canonical_path, &error_msg);
 930       }
 931       if (zip != NULL && error_msg == NULL) {
 932         new_entry = new ClassPathZipEntry(zip, path, is_boot_append);
 933       } else {
 934         char *msg;
 935         if (error_msg == NULL) {
 936           msg = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, strlen(path) + 128); ;
 937           jio_snprintf(msg, strlen(path) + 127, "error in opening JAR file %s", path);
 938         } else {
 939           int len = (int)(strlen(path) + strlen(error_msg) + 128);
 940           msg = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, len); ;
 941           jio_snprintf(msg, len - 1, "error in opening JAR file <%s> %s", error_msg, path);
 942         }
 943         // Don't complain about bad jar files added via -Xbootclasspath/a:.
 944         if (throw_exception && is_init_completed()) {
 945           THROW_MSG_(vmSymbols::java_lang_ClassNotFoundException(), msg, NULL);
 946         } else {
 947           return NULL;
 948         }
 949       }
 950     }
 951     log_info(class, path)("opened: %s", path);
 952     log_info(class, load)("opened: %s", path);
 953   } else {
 954     // Directory
 955     new_entry = new ClassPathDirEntry(path);
 956     log_info(class, load)("path: %s", path);
 957   }
 958   return new_entry;
 959 }
 960 
 961 
 962 // Create a class path zip entry for a given path (return NULL if not found
 963 // or zip/JAR file cannot be opened)
 964 ClassPathZipEntry* ClassLoader::create_class_path_zip_entry(const char *path, bool is_boot_append) {
 965   // check for a regular file
 966   struct stat st;
 967   if (os::stat(path, &st) == 0) {
 968     if ((st.st_mode & S_IFMT) == S_IFREG) {
 969       char canonical_path[JVM_MAXPATHLEN];
 970       if (get_canonical_path(path, canonical_path, JVM_MAXPATHLEN)) {
 971         char* error_msg = NULL;
 972         jzfile* zip;
 973         {
 974           // enable call to C land
 975           JavaThread* thread = JavaThread::current();
 976           ThreadToNativeFromVM ttn(thread);
 977           HandleMark hm(thread);
 978           zip = (*ZipOpen)(canonical_path, &error_msg);
 979         }
 980         if (zip != NULL && error_msg == NULL) {
 981           // create using canonical path
 982           return new ClassPathZipEntry(zip, canonical_path, is_boot_append);
 983         }
 984       }
 985     }
 986   }
 987   return NULL;
 988 }
 989 
 990 // returns true if entry already on class path
 991 bool ClassLoader::contains_append_entry(const char* name) {
 992   ClassPathEntry* e = _first_append_entry;
 993   while (e != NULL) {
 994     // assume zip entries have been canonicalized
 995     if (strcmp(name, e->name()) == 0) {
 996       return true;
 997     }
 998     e = e->next();
 999   }
1000   return false;
1001 }
1002 
1003 void ClassLoader::add_to_boot_append_entries(ClassPathEntry *new_entry) {
1004   if (new_entry != NULL) {
1005     if (_last_append_entry == NULL) {
1006       assert(_first_append_entry == NULL, "boot loader's append class path entry list not empty");
1007       _first_append_entry = _last_append_entry = new_entry;
1008     } else {
1009       _last_append_entry->set_next(new_entry);
1010       _last_append_entry = new_entry;
1011     }
1012   }
1013 }
1014 
1015 // Record the path entries specified in -cp during dump time. The recorded
1016 // information will be used at runtime for loading the archived app classes.
1017 //
1018 // Note that at dump time, ClassLoader::_app_classpath_entries are NOT used for
1019 // loading app classes. Instead, the app class are loaded by the
1020 // jdk/internal/loader/ClassLoaders$AppClassLoader instance.
1021 void ClassLoader::add_to_app_classpath_entries(const char* path,
1022                                                ClassPathEntry* entry,
1023                                                bool check_for_duplicates) {
1024 #if INCLUDE_CDS
1025   assert(entry != NULL, "ClassPathEntry should not be NULL");
1026   ClassPathEntry* e = _app_classpath_entries;
1027   if (check_for_duplicates) {
1028     while (e != NULL) {
1029       if (strcmp(e->name(), entry->name()) == 0) {
1030         // entry already exists
1031         return;
1032       }
1033       e = e->next();
1034     }
1035   }
1036 
1037   // The entry does not exist, add to the list
1038   if (_app_classpath_entries == NULL) {
1039     assert(_last_app_classpath_entry == NULL, "Sanity");
1040     _app_classpath_entries = _last_app_classpath_entry = entry;
1041   } else {
1042     _last_app_classpath_entry->set_next(entry);
1043     _last_app_classpath_entry = entry;
1044   }
1045 
1046   if (entry->is_jar_file()) {
1047     ClassLoaderExt::process_jar_manifest(entry, check_for_duplicates);
1048   }
1049 #endif
1050 }
1051 
1052 // Returns true IFF the file/dir exists and the entry was successfully created.
1053 bool ClassLoader::update_class_path_entry_list(const char *path,
1054                                                bool check_for_duplicates,
1055                                                bool is_boot_append,
1056                                                bool throw_exception) {
1057   struct stat st;
1058   if (os::stat(path, &st) == 0) {
1059     // File or directory found
1060     ClassPathEntry* new_entry = NULL;
1061     Thread* THREAD = Thread::current();
1062     new_entry = create_class_path_entry(path, &st, throw_exception, is_boot_append, CHECK_(false));
1063     if (new_entry == NULL) {
1064       return false;
1065     }
1066 
1067     // Do not reorder the bootclasspath which would break get_system_package().
1068     // Add new entry to linked list
1069     if (is_boot_append) {
1070       add_to_boot_append_entries(new_entry);
1071     } else {
1072       add_to_app_classpath_entries(path, new_entry, check_for_duplicates);
1073     }
1074     return true;
1075   } else {
1076 #if INCLUDE_CDS
1077     if (DumpSharedSpaces) {
1078       _shared_paths_misc_info->add_nonexist_path(path);
1079     }
1080 #endif
1081     return false;
1082   }
1083 }
1084 
1085 static void print_module_entry_table(const GrowableArray<ModuleClassPathList*>* const module_list) {
1086   ResourceMark rm;
1087   int num_of_entries = module_list->length();
1088   for (int i = 0; i < num_of_entries; i++) {
1089     ClassPathEntry* e;
1090     ModuleClassPathList* mpl = module_list->at(i);
1091     tty->print("%s=", mpl->module_name()->as_C_string());
1092     e = mpl->module_first_entry();
1093     while (e != NULL) {
1094       tty->print("%s", e->name());
1095       e = e->next();
1096       if (e != NULL) {
1097         tty->print("%s", os::path_separator());
1098       }
1099     }
1100     tty->print(" ;");
1101   }
1102 }
1103 
1104 void ClassLoader::print_bootclasspath() {
1105   ClassPathEntry* e;
1106   tty->print("[bootclasspath= ");
1107 
1108   // Print --patch-module module/path specifications first
1109   if (_patch_mod_entries != NULL) {
1110     print_module_entry_table(_patch_mod_entries);
1111   }
1112 
1113   // [jimage | exploded modules build]
1114   if (has_jrt_entry()) {
1115     // Print the location of the java runtime image
1116     tty->print("%s ;", _jrt_entry->name());
1117   } else {
1118     // Print exploded module build path specifications
1119     if (_exploded_entries != NULL) {
1120       print_module_entry_table(_exploded_entries);
1121     }
1122   }
1123 
1124   // appended entries
1125   e = _first_append_entry;
1126   while (e != NULL) {
1127     tty->print("%s ;", e->name());
1128     e = e->next();
1129   }
1130   tty->print_cr("]");
1131 }
1132 
1133 void ClassLoader::load_zip_library() {
1134   assert(ZipOpen == NULL, "should not load zip library twice");
1135   // First make sure native library is loaded
1136   os::native_java_library();
1137   // Load zip library
1138   char path[JVM_MAXPATHLEN];
1139   char ebuf[1024];
1140   void* handle = NULL;
1141   if (os::dll_locate_lib(path, sizeof(path), Arguments::get_dll_dir(), "zip")) {
1142     handle = os::dll_load(path, ebuf, sizeof ebuf);
1143   }
1144   if (handle == NULL) {
1145     vm_exit_during_initialization("Unable to load ZIP library", path);
1146   }
1147   // Lookup zip entry points
1148   ZipOpen      = CAST_TO_FN_PTR(ZipOpen_t, os::dll_lookup(handle, "ZIP_Open"));
1149   ZipClose     = CAST_TO_FN_PTR(ZipClose_t, os::dll_lookup(handle, "ZIP_Close"));
1150   FindEntry    = CAST_TO_FN_PTR(FindEntry_t, os::dll_lookup(handle, "ZIP_FindEntry"));
1151   ReadEntry    = CAST_TO_FN_PTR(ReadEntry_t, os::dll_lookup(handle, "ZIP_ReadEntry"));
1152   GetNextEntry = CAST_TO_FN_PTR(GetNextEntry_t, os::dll_lookup(handle, "ZIP_GetNextEntry"));
1153   ZipInflateFully = CAST_TO_FN_PTR(ZipInflateFully_t, os::dll_lookup(handle, "ZIP_InflateFully"));
1154   Crc32        = CAST_TO_FN_PTR(Crc32_t, os::dll_lookup(handle, "ZIP_CRC32"));
1155 
1156   // ZIP_Close is not exported on Windows in JDK5.0 so don't abort if ZIP_Close is NULL
1157   if (ZipOpen == NULL || FindEntry == NULL || ReadEntry == NULL ||
1158       GetNextEntry == NULL || Crc32 == NULL) {
1159     vm_exit_during_initialization("Corrupted ZIP library", path);
1160   }
1161 
1162   if (ZipInflateFully == NULL) {
1163     vm_exit_during_initialization("Corrupted ZIP library ZIP_InflateFully missing", path);
1164   }
1165 
1166   // Lookup canonicalize entry in libjava.dll
1167   void *javalib_handle = os::native_java_library();
1168   CanonicalizeEntry = CAST_TO_FN_PTR(canonicalize_fn_t, os::dll_lookup(javalib_handle, "Canonicalize"));
1169   // This lookup only works on 1.3. Do not check for non-null here
1170 }
1171 
1172 void ClassLoader::load_jimage_library() {
1173   // First make sure native library is loaded
1174   os::native_java_library();
1175   // Load jimage library
1176   char path[JVM_MAXPATHLEN];
1177   char ebuf[1024];
1178   void* handle = NULL;
1179   if (os::dll_locate_lib(path, sizeof(path), Arguments::get_dll_dir(), "jimage")) {
1180     handle = os::dll_load(path, ebuf, sizeof ebuf);
1181   }
1182   if (handle == NULL) {
1183     vm_exit_during_initialization("Unable to load jimage library", path);
1184   }
1185 
1186   // Lookup jimage entry points
1187   JImageOpen = CAST_TO_FN_PTR(JImageOpen_t, os::dll_lookup(handle, "JIMAGE_Open"));
1188   guarantee(JImageOpen != NULL, "function JIMAGE_Open not found");
1189   JImageClose = CAST_TO_FN_PTR(JImageClose_t, os::dll_lookup(handle, "JIMAGE_Close"));
1190   guarantee(JImageClose != NULL, "function JIMAGE_Close not found");
1191   JImagePackageToModule = CAST_TO_FN_PTR(JImagePackageToModule_t, os::dll_lookup(handle, "JIMAGE_PackageToModule"));
1192   guarantee(JImagePackageToModule != NULL, "function JIMAGE_PackageToModule not found");
1193   JImageFindResource = CAST_TO_FN_PTR(JImageFindResource_t, os::dll_lookup(handle, "JIMAGE_FindResource"));
1194   guarantee(JImageFindResource != NULL, "function JIMAGE_FindResource not found");
1195   JImageGetResource = CAST_TO_FN_PTR(JImageGetResource_t, os::dll_lookup(handle, "JIMAGE_GetResource"));
1196   guarantee(JImageGetResource != NULL, "function JIMAGE_GetResource not found");
1197   JImageResourceIterator = CAST_TO_FN_PTR(JImageResourceIterator_t, os::dll_lookup(handle, "JIMAGE_ResourceIterator"));
1198   guarantee(JImageResourceIterator != NULL, "function JIMAGE_ResourceIterator not found");
1199   JImageResourcePath = CAST_TO_FN_PTR(JImage_ResourcePath_t, os::dll_lookup(handle, "JIMAGE_ResourcePath"));
1200   guarantee(JImageResourcePath != NULL, "function JIMAGE_ResourcePath not found");
1201 }
1202 
1203 jboolean ClassLoader::decompress(void *in, u8 inSize, void *out, u8 outSize, char **pmsg) {
1204   return (*ZipInflateFully)(in, inSize, out, outSize, pmsg);
1205 }
1206 
1207 int ClassLoader::crc32(int crc, const char* buf, int len) {
1208   assert(Crc32 != NULL, "ZIP_CRC32 is not found");
1209   return (*Crc32)(crc, (const jbyte*)buf, len);
1210 }
1211 
1212 // Function add_package extracts the package from the fully qualified class name
1213 // and checks if the package is in the boot loader's package entry table.  If so,
1214 // then it sets the classpath_index in the package entry record.
1215 //
1216 // The classpath_index field is used to find the entry on the boot loader class
1217 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
1218 // in an unnamed module.  It is also used to indicate (for all packages whose
1219 // classes are loaded by the boot loader) that at least one of the package's
1220 // classes has been loaded.
1221 bool ClassLoader::add_package(const char *fullq_class_name, s2 classpath_index, TRAPS) {
1222   assert(fullq_class_name != NULL, "just checking");
1223 
1224   // Get package name from fully qualified class name.
1225   ResourceMark rm;
1226   const char *cp = package_from_name(fullq_class_name);
1227   if (cp != NULL) {
1228     PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();
1229     TempNewSymbol pkg_symbol = SymbolTable::new_symbol(cp, CHECK_false);
1230     PackageEntry* pkg_entry = pkg_entry_tbl->lookup_only(pkg_symbol);
1231     if (pkg_entry != NULL) {
1232       assert(classpath_index != -1, "Unexpected classpath_index");
1233       pkg_entry->set_classpath_index(classpath_index);
1234     } else {
1235       return false;
1236     }
1237   }
1238   return true;
1239 }
1240 
1241 oop ClassLoader::get_system_package(const char* name, TRAPS) {
1242   // Look up the name in the boot loader's package entry table.
1243   if (name != NULL) {
1244     TempNewSymbol package_sym = SymbolTable::new_symbol(name, (int)strlen(name), CHECK_NULL);
1245     // Look for the package entry in the boot loader's package entry table.
1246     PackageEntry* package =
1247       ClassLoaderData::the_null_class_loader_data()->packages()->lookup_only(package_sym);
1248 
1249     // Return NULL if package does not exist or if no classes in that package
1250     // have been loaded.
1251     if (package != NULL && package->has_loaded_class()) {
1252       ModuleEntry* module = package->module();
1253       if (module->location() != NULL) {
1254         ResourceMark rm(THREAD);
1255         Handle ml = java_lang_String::create_from_str(
1256           module->location()->as_C_string(), THREAD);
1257         return ml();
1258       }
1259       // Return entry on boot loader class path.
1260       Handle cph = java_lang_String::create_from_str(
1261         ClassLoader::classpath_entry(package->classpath_index())->name(), THREAD);
1262       return cph();
1263     }
1264   }
1265   return NULL;
1266 }
1267 
1268 objArrayOop ClassLoader::get_system_packages(TRAPS) {
1269   ResourceMark rm(THREAD);
1270   // List of pointers to PackageEntrys that have loaded classes.
1271   GrowableArray<PackageEntry*>* loaded_class_pkgs = new GrowableArray<PackageEntry*>(50);
1272   {
1273     MutexLocker ml(Module_lock, THREAD);
1274 
1275     PackageEntryTable* pe_table =
1276       ClassLoaderData::the_null_class_loader_data()->packages();
1277 
1278     // Collect the packages that have at least one loaded class.
1279     for (int x = 0; x < pe_table->table_size(); x++) {
1280       for (PackageEntry* package_entry = pe_table->bucket(x);
1281            package_entry != NULL;
1282            package_entry = package_entry->next()) {
1283         if (package_entry->has_loaded_class()) {
1284           loaded_class_pkgs->append(package_entry);
1285         }
1286       }
1287     }
1288   }
1289 
1290 
1291   // Allocate objArray and fill with java.lang.String
1292   objArrayOop r = oopFactory::new_objArray(SystemDictionary::String_klass(),
1293                                            loaded_class_pkgs->length(), CHECK_NULL);
1294   objArrayHandle result(THREAD, r);
1295   for (int x = 0; x < loaded_class_pkgs->length(); x++) {
1296     PackageEntry* package_entry = loaded_class_pkgs->at(x);
1297     Handle str = java_lang_String::create_from_symbol(package_entry->name(), CHECK_NULL);
1298     result->obj_at_put(x, str());
1299   }
1300   return result();
1301 }
1302 
1303 // caller needs ResourceMark
1304 const char* ClassLoader::file_name_for_class_name(const char* class_name,
1305                                                   int class_name_len) {
1306   assert(class_name != NULL, "invariant");
1307   assert((int)strlen(class_name) == class_name_len, "invariant");
1308 
1309   static const char class_suffix[] = ".class";
1310 
1311   char* const file_name = NEW_RESOURCE_ARRAY(char,
1312                                              class_name_len +
1313                                              sizeof(class_suffix)); // includes term NULL
1314 
1315   strncpy(file_name, class_name, class_name_len);
1316   strncpy(&file_name[class_name_len], class_suffix, sizeof(class_suffix));
1317 
1318   return file_name;
1319 }
1320 
1321 ClassPathEntry* find_first_module_cpe(ModuleEntry* mod_entry,
1322                                       const GrowableArray<ModuleClassPathList*>* const module_list) {
1323   int num_of_entries = module_list->length();
1324   const Symbol* class_module_name = mod_entry->name();
1325 
1326   // Loop through all the modules in either the patch-module or exploded entries looking for module
1327   for (int i = 0; i < num_of_entries; i++) {
1328     ModuleClassPathList* module_cpl = module_list->at(i);
1329     Symbol* module_cpl_name = module_cpl->module_name();
1330 
1331     if (module_cpl_name->fast_compare(class_module_name) == 0) {
1332       // Class' module has been located.
1333       return module_cpl->module_first_entry();
1334     }
1335   }
1336   return NULL;
1337 }
1338 
1339 
1340 // Search either the patch-module or exploded build entries for class.
1341 ClassFileStream* ClassLoader::search_module_entries(const GrowableArray<ModuleClassPathList*>* const module_list,
1342                                                     const char* const class_name,
1343                                                     const char* const file_name,
1344                                                     TRAPS) {
1345   ClassFileStream* stream = NULL;
1346 
1347   // Find the class' defining module in the boot loader's module entry table
1348   PackageEntry* pkg_entry = get_package_entry(class_name, ClassLoaderData::the_null_class_loader_data(), CHECK_NULL);
1349   ModuleEntry* mod_entry = (pkg_entry != NULL) ? pkg_entry->module() : NULL;
1350 
1351   // If the module system has not defined java.base yet, then
1352   // classes loaded are assumed to be defined to java.base.
1353   // When java.base is eventually defined by the module system,
1354   // all packages of classes that have been previously loaded
1355   // are verified in ModuleEntryTable::verify_javabase_packages().
1356   if (!Universe::is_module_initialized() &&
1357       !ModuleEntryTable::javabase_defined() &&
1358       mod_entry == NULL) {
1359     mod_entry = ModuleEntryTable::javabase_moduleEntry();
1360   }
1361 
1362   // The module must be a named module
1363   ClassPathEntry* e = NULL;
1364   if (mod_entry != NULL && mod_entry->is_named()) {
1365     if (module_list == _exploded_entries) {
1366       // The exploded build entries can be added to at any time so a lock is
1367       // needed when searching them.
1368       assert(!ClassLoader::has_jrt_entry(), "Must be exploded build");
1369       MutexLocker ml(Module_lock, THREAD);
1370       e = find_first_module_cpe(mod_entry, module_list);
1371     } else {
1372       e = find_first_module_cpe(mod_entry, module_list);
1373     }
1374   }
1375 
1376   // Try to load the class from the module's ClassPathEntry list.
1377   while (e != NULL) {
1378     stream = e->open_stream(file_name, CHECK_NULL);
1379     // No context.check is required since CDS is not supported
1380     // for an exploded modules build or if --patch-module is specified.
1381     if (NULL != stream) {
1382       return stream;
1383     }
1384     e = e->next();
1385   }
1386   // If the module was located, break out even if the class was not
1387   // located successfully from that module's ClassPathEntry list.
1388   // There will not be another valid entry for that module.
1389   return NULL;
1390 }
1391 
1392 // Called by the boot classloader to load classes
1393 InstanceKlass* ClassLoader::load_class(Symbol* name, bool search_append_only, TRAPS) {
1394   assert(name != NULL, "invariant");
1395   assert(THREAD->is_Java_thread(), "must be a JavaThread");
1396 
1397   ResourceMark rm(THREAD);
1398   HandleMark hm(THREAD);
1399 
1400   const char* const class_name = name->as_C_string();
1401 
1402   EventMark m("loading class %s", class_name);
1403 
1404   const char* const file_name = file_name_for_class_name(class_name,
1405                                                          name->utf8_length());
1406   assert(file_name != NULL, "invariant");
1407 
1408   // Lookup stream for parsing .class file
1409   ClassFileStream* stream = NULL;
1410   s2 classpath_index = 0;
1411   ClassPathEntry* e = NULL;
1412 
1413   // If DumpSharedSpaces is true boot loader visibility boundaries are set to:
1414   //   - [jimage] + [_first_append_entry to _last_append_entry] (all path entries).
1415   //
1416   // If search_append_only is true, boot loader visibility boundaries are
1417   // set to be _first_append_entry to the end. This includes:
1418   //   [-Xbootclasspath/a]; [jvmti appended entries]
1419   //
1420   // If both DumpSharedSpaces and search_append_only are false, boot loader
1421   // visibility boundaries are set to be the --patch-module entries plus the base piece.
1422   // This would include:
1423   //   [--patch-module=<module>=<file>(<pathsep><file>)*]; [jimage | exploded module build]
1424   //
1425 
1426   // Load Attempt #1: --patch-module
1427   // Determine the class' defining module.  If it appears in the _patch_mod_entries,
1428   // attempt to load the class from those locations specific to the module.
1429   // Specifications to --patch-module can contain a partial number of classes
1430   // that are part of the overall module definition.  So if a particular class is not
1431   // found within its module specification, the search should continue to Load Attempt #2.
1432   // Note: The --patch-module entries are never searched if the boot loader's
1433   //       visibility boundary is limited to only searching the append entries.
1434   if (_patch_mod_entries != NULL && !search_append_only) {
1435     // At CDS dump time, the --patch-module entries are ignored. That means a
1436     // class is still loaded from the runtime image even if it might
1437     // appear in the _patch_mod_entries. The runtime shared class visibility
1438     // check will determine if a shared class is visible based on the runtime
1439     // environemnt, including the runtime --patch-module setting.
1440     if (!DumpSharedSpaces) {
1441       stream = search_module_entries(_patch_mod_entries, class_name, file_name, CHECK_NULL);
1442     }
1443   }
1444 
1445   // Load Attempt #2: [jimage | exploded build]
1446   if (!search_append_only && (NULL == stream)) {
1447     if (has_jrt_entry()) {
1448       e = _jrt_entry;
1449       stream = _jrt_entry->open_stream(file_name, CHECK_NULL);
1450     } else {
1451       // Exploded build - attempt to locate class in its defining module's location.
1452       assert(_exploded_entries != NULL, "No exploded build entries present");
1453       stream = search_module_entries(_exploded_entries, class_name, file_name, CHECK_NULL);
1454     }
1455   }
1456 
1457   // Load Attempt #3: [-Xbootclasspath/a]; [jvmti appended entries]
1458   if ((search_append_only || DumpSharedSpaces) && (NULL == stream)) {
1459     // For the boot loader append path search, the starting classpath_index
1460     // for the appended piece is always 1 to account for either the
1461     // _jrt_entry or the _exploded_entries.
1462     assert(classpath_index == 0, "The classpath_index has been incremented incorrectly");
1463     classpath_index = 1;
1464 
1465     e = _first_append_entry;
1466     while (e != NULL) {
1467       stream = e->open_stream(file_name, CHECK_NULL);
1468       if (NULL != stream) {
1469         break;
1470       }
1471       e = e->next();
1472       ++classpath_index;
1473     }
1474   }
1475 
1476   if (NULL == stream) {
1477     return NULL;
1478   }
1479 
1480   stream->set_verify(ClassLoaderExt::should_verify(classpath_index));
1481 
1482   ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
1483   Handle protection_domain;
1484 
1485   InstanceKlass* result = KlassFactory::create_from_stream(stream,
1486                                                            name,
1487                                                            loader_data,
1488                                                            protection_domain,
1489                                                            NULL, // host_klass
1490                                                            NULL, // cp_patches
1491                                                            THREAD);
1492   if (HAS_PENDING_EXCEPTION) {
1493     if (DumpSharedSpaces) {
1494       tty->print_cr("Preload Error: Failed to load %s", class_name);
1495     }
1496     return NULL;
1497   }
1498 
1499   if (!add_package(file_name, classpath_index, THREAD)) {
1500     return NULL;
1501   }
1502 
1503   return result;
1504 }
1505 
1506 #if INCLUDE_CDS
1507 char* ClassLoader::skip_uri_protocol(char* source) {
1508   if (strncmp(source, "file:", 5) == 0) {
1509     // file: protocol path could start with file:/ or file:///
1510     // locate the char after all the forward slashes
1511     int offset = 5;
1512     while (*(source + offset) == '/') {
1513         offset++;
1514     }
1515     source += offset;
1516   // for non-windows platforms, move back one char as the path begins with a '/'
1517 #ifndef _WINDOWS
1518     source -= 1;
1519 #endif
1520   } else if (strncmp(source, "jrt:/", 5) == 0) {
1521     source += 5;
1522   }
1523   return source;
1524 }
1525 
1526 // Record the shared classpath index and loader type for classes loaded
1527 // by the builtin loaders at dump time.
1528 void ClassLoader::record_result(InstanceKlass* ik, const ClassFileStream* stream, TRAPS) {
1529   assert(DumpSharedSpaces, "sanity");
1530   assert(stream != NULL, "sanity");
1531 
1532   if (ik->is_anonymous()) {
1533     // We do not archive anonymous classes.
1534     return;
1535   }
1536 
1537   oop loader = ik->class_loader();
1538   char* src = (char*)stream->source();
1539   if (src == NULL) {
1540     if (loader == NULL) {
1541       // JFR classes
1542       ik->set_shared_classpath_index(0);
1543       ik->set_class_loader_type(ClassLoader::BOOT_LOADER);
1544     }
1545     return;
1546   }
1547 
1548   assert(has_jrt_entry(), "CDS dumping does not support exploded JDK build");
1549 
1550   ResourceMark rm(THREAD);
1551   int classpath_index = -1;
1552   PackageEntry* pkg_entry = ik->package();
1553 
1554   if (FileMapInfo::get_number_of_shared_paths() > 0) {
1555     char* canonical_path = NEW_RESOURCE_ARRAY(char, JVM_MAXPATHLEN);
1556 
1557     // save the path from the file: protocol or the module name from the jrt: protocol
1558     // if no protocol prefix is found, path is the same as stream->source()
1559     char* path = skip_uri_protocol(src);
1560     for (int i = 0; i < FileMapInfo::get_number_of_shared_paths(); i++) {
1561       SharedClassPathEntry* ent = FileMapInfo::shared_path(i);
1562       if (get_canonical_path(ent->name(), canonical_path, JVM_MAXPATHLEN)) {
1563         // If the path (from the class stream source) is the same as the shared
1564         // class or module path, then we have a match.
1565         if (strcmp(canonical_path, os::native_path((char*)path)) == 0) {
1566           // NULL pkg_entry and pkg_entry in an unnamed module implies the class
1567           // is from the -cp or boot loader append path which consists of -Xbootclasspath/a
1568           // and jvmti appended entries.
1569           if ((pkg_entry == NULL) || (pkg_entry->in_unnamed_module())) {
1570             // Ensure the index is within the -cp range before assigning
1571             // to the classpath_index.
1572             if (SystemDictionary::is_system_class_loader(loader) &&
1573                 (i >= ClassLoaderExt::app_class_paths_start_index()) &&
1574                 (i < ClassLoaderExt::app_module_paths_start_index())) {
1575               classpath_index = i;
1576               break;
1577             } else {
1578               if ((i >= 1) &&
1579                   (i < ClassLoaderExt::app_class_paths_start_index())) {
1580                 // The class must be from boot loader append path which consists of
1581                 // -Xbootclasspath/a and jvmti appended entries.
1582                 assert(loader == NULL, "sanity");
1583                 classpath_index = i;
1584                 break;
1585               }
1586             }
1587           } else {
1588             // A class from a named module from the --module-path. Ensure the index is
1589             // within the --module-path range before assigning to the classpath_index.
1590             if ((pkg_entry != NULL) && !(pkg_entry->in_unnamed_module()) && (i > 0)) {
1591               if (i >= ClassLoaderExt::app_module_paths_start_index() &&
1592                   i < FileMapInfo::get_number_of_shared_paths()) {
1593                 classpath_index = i;
1594                 break;
1595               }
1596             }
1597           }
1598         }
1599         // for index 0 and the stream->source() is the modules image or has the jrt: protocol.
1600         // The class must be from the runtime modules image.
1601         if (i == 0 && (is_modules_image(src) || string_starts_with(src, "jrt:"))) {
1602           classpath_index = i;
1603           break;
1604         }
1605       }
1606     }
1607 
1608     // No path entry found for this class. Must be a shared class loaded by the
1609     // user defined classloader.
1610     if (classpath_index < 0) {
1611       assert(ik->shared_classpath_index() < 0, "Sanity");
1612       return;
1613     }
1614   } else {
1615     // The shared path table is set up after module system initialization.
1616     // The path table contains no entry before that. Any classes loaded prior
1617     // to the setup of the shared path table must be from the modules image.
1618     assert(is_modules_image(src), "stream must be from modules image");
1619     assert(FileMapInfo::get_number_of_shared_paths() == 0, "shared path table must not have been setup");
1620     classpath_index = 0;
1621   }
1622 
1623   const char* const class_name = ik->name()->as_C_string();
1624   const char* const file_name = file_name_for_class_name(class_name,
1625                                                          ik->name()->utf8_length());
1626   assert(file_name != NULL, "invariant");
1627 
1628   ClassLoaderExt::record_result(classpath_index, ik, THREAD);
1629 }
1630 #endif // INCLUDE_CDS
1631 
1632 // Initialize the class loader's access to methods in libzip.  Parse and
1633 // process the boot classpath into a list ClassPathEntry objects.  Once
1634 // this list has been created, it must not change order (see class PackageInfo)
1635 // it can be appended to and is by jvmti and the kernel vm.
1636 
1637 void ClassLoader::initialize() {
1638   EXCEPTION_MARK;
1639 
1640   if (UsePerfData) {
1641     // jvmstat performance counters
1642     NEWPERFTICKCOUNTER(_perf_accumulated_time, SUN_CLS, "time");
1643     NEWPERFTICKCOUNTER(_perf_class_init_time, SUN_CLS, "classInitTime");
1644     NEWPERFTICKCOUNTER(_perf_class_init_selftime, SUN_CLS, "classInitTime.self");
1645     NEWPERFTICKCOUNTER(_perf_class_verify_time, SUN_CLS, "classVerifyTime");
1646     NEWPERFTICKCOUNTER(_perf_class_verify_selftime, SUN_CLS, "classVerifyTime.self");
1647     NEWPERFTICKCOUNTER(_perf_class_link_time, SUN_CLS, "classLinkedTime");
1648     NEWPERFTICKCOUNTER(_perf_class_link_selftime, SUN_CLS, "classLinkedTime.self");
1649     NEWPERFEVENTCOUNTER(_perf_classes_inited, SUN_CLS, "initializedClasses");
1650     NEWPERFEVENTCOUNTER(_perf_classes_linked, SUN_CLS, "linkedClasses");
1651     NEWPERFEVENTCOUNTER(_perf_classes_verified, SUN_CLS, "verifiedClasses");
1652 
1653     NEWPERFTICKCOUNTER(_perf_class_parse_time, SUN_CLS, "parseClassTime");
1654     NEWPERFTICKCOUNTER(_perf_class_parse_selftime, SUN_CLS, "parseClassTime.self");
1655     NEWPERFTICKCOUNTER(_perf_sys_class_lookup_time, SUN_CLS, "lookupSysClassTime");
1656     NEWPERFTICKCOUNTER(_perf_shared_classload_time, SUN_CLS, "sharedClassLoadTime");
1657     NEWPERFTICKCOUNTER(_perf_sys_classload_time, SUN_CLS, "sysClassLoadTime");
1658     NEWPERFTICKCOUNTER(_perf_app_classload_time, SUN_CLS, "appClassLoadTime");
1659     NEWPERFTICKCOUNTER(_perf_app_classload_selftime, SUN_CLS, "appClassLoadTime.self");
1660     NEWPERFEVENTCOUNTER(_perf_app_classload_count, SUN_CLS, "appClassLoadCount");
1661     NEWPERFTICKCOUNTER(_perf_define_appclasses, SUN_CLS, "defineAppClasses");
1662     NEWPERFTICKCOUNTER(_perf_define_appclass_time, SUN_CLS, "defineAppClassTime");
1663     NEWPERFTICKCOUNTER(_perf_define_appclass_selftime, SUN_CLS, "defineAppClassTime.self");
1664     NEWPERFBYTECOUNTER(_perf_app_classfile_bytes_read, SUN_CLS, "appClassBytes");
1665     NEWPERFBYTECOUNTER(_perf_sys_classfile_bytes_read, SUN_CLS, "sysClassBytes");
1666 
1667 
1668     // The following performance counters are added for measuring the impact
1669     // of the bug fix of 6365597. They are mainly focused on finding out
1670     // the behavior of system & user-defined classloader lock, whether
1671     // ClassLoader.loadClass/findClass is being called synchronized or not.
1672     NEWPERFEVENTCOUNTER(_sync_systemLoaderLockContentionRate, SUN_CLS,
1673                         "systemLoaderLockContentionRate");
1674     NEWPERFEVENTCOUNTER(_sync_nonSystemLoaderLockContentionRate, SUN_CLS,
1675                         "nonSystemLoaderLockContentionRate");
1676     NEWPERFEVENTCOUNTER(_sync_JVMFindLoadedClassLockFreeCounter, SUN_CLS,
1677                         "jvmFindLoadedClassNoLockCalls");
1678     NEWPERFEVENTCOUNTER(_sync_JVMDefineClassLockFreeCounter, SUN_CLS,
1679                         "jvmDefineClassNoLockCalls");
1680 
1681     NEWPERFEVENTCOUNTER(_sync_JNIDefineClassLockFreeCounter, SUN_CLS,
1682                         "jniDefineClassNoLockCalls");
1683 
1684     NEWPERFEVENTCOUNTER(_unsafe_defineClassCallCounter, SUN_CLS,
1685                         "unsafeDefineClassCalls");
1686 
1687     NEWPERFEVENTCOUNTER(_load_instance_class_failCounter, SUN_CLS,
1688                         "loadInstanceClassFailRate");
1689   }
1690 
1691   // lookup zip library entry points
1692   load_zip_library();
1693   // lookup jimage library entry points
1694   load_jimage_library();
1695 #if INCLUDE_CDS
1696   // initialize search path
1697   if (DumpSharedSpaces) {
1698     _shared_paths_misc_info = new SharedPathsMiscInfo();
1699   }
1700 #endif
1701   setup_bootstrap_search_path();
1702 }
1703 
1704 #if INCLUDE_CDS
1705 void ClassLoader::initialize_shared_path() {
1706   if (DumpSharedSpaces) {
1707     ClassLoaderExt::setup_search_paths();
1708     _shared_paths_misc_info->write_jint(0); // see comments in SharedPathsMiscInfo::check()
1709   }
1710 }
1711 
1712 void ClassLoader::initialize_module_path(TRAPS) {
1713   if (DumpSharedSpaces) {
1714     ClassLoaderExt::setup_module_paths(THREAD);
1715     FileMapInfo::allocate_shared_path_table();
1716   }
1717 }
1718 #endif
1719 
1720 jlong ClassLoader::classloader_time_ms() {
1721   return UsePerfData ?
1722     Management::ticks_to_ms(_perf_accumulated_time->get_value()) : -1;
1723 }
1724 
1725 jlong ClassLoader::class_init_count() {
1726   return UsePerfData ? _perf_classes_inited->get_value() : -1;
1727 }
1728 
1729 jlong ClassLoader::class_init_time_ms() {
1730   return UsePerfData ?
1731     Management::ticks_to_ms(_perf_class_init_time->get_value()) : -1;
1732 }
1733 
1734 jlong ClassLoader::class_verify_time_ms() {
1735   return UsePerfData ?
1736     Management::ticks_to_ms(_perf_class_verify_time->get_value()) : -1;
1737 }
1738 
1739 jlong ClassLoader::class_link_count() {
1740   return UsePerfData ? _perf_classes_linked->get_value() : -1;
1741 }
1742 
1743 jlong ClassLoader::class_link_time_ms() {
1744   return UsePerfData ?
1745     Management::ticks_to_ms(_perf_class_link_time->get_value()) : -1;
1746 }
1747 
1748 int ClassLoader::compute_Object_vtable() {
1749   // hardwired for JDK1.2 -- would need to duplicate class file parsing
1750   // code to determine actual value from file
1751   // Would be value '11' if finals were in vtable
1752   int JDK_1_2_Object_vtable_size = 5;
1753   return JDK_1_2_Object_vtable_size * vtableEntry::size();
1754 }
1755 
1756 
1757 void classLoader_init1() {
1758   ClassLoader::initialize();
1759 }
1760 
1761 // Complete the ClassPathEntry setup for the boot loader
1762 void ClassLoader::classLoader_init2(TRAPS) {
1763   // Setup the list of module/path pairs for --patch-module processing
1764   // This must be done after the SymbolTable is created in order
1765   // to use fast_compare on module names instead of a string compare.
1766   if (Arguments::get_patch_mod_prefix() != NULL) {
1767     setup_patch_mod_entries();
1768   }
1769 
1770   // Create the ModuleEntry for java.base (must occur after setup_patch_mod_entries
1771   // to successfully determine if java.base has been patched)
1772   create_javabase();
1773 
1774   // Setup the initial java.base/path pair for the exploded build entries.
1775   // As more modules are defined during module system initialization, more
1776   // entries will be added to the exploded build array.
1777   if (!has_jrt_entry()) {
1778     assert(!DumpSharedSpaces, "DumpSharedSpaces not supported with exploded module builds");
1779     assert(!UseSharedSpaces, "UsedSharedSpaces not supported with exploded module builds");
1780     // Set up the boot loader's _exploded_entries list.  Note that this gets
1781     // done before loading any classes, by the same thread that will
1782     // subsequently do the first class load. So, no lock is needed for this.
1783     assert(_exploded_entries == NULL, "Should only get initialized once");
1784     _exploded_entries = new (ResourceObj::C_HEAP, mtModule)
1785       GrowableArray<ModuleClassPathList*>(EXPLODED_ENTRY_SIZE, true);
1786     add_to_exploded_build_list(vmSymbols::java_base(), CHECK);
1787   }
1788 }
1789 
1790 
1791 bool ClassLoader::get_canonical_path(const char* orig, char* out, int len) {
1792   assert(orig != NULL && out != NULL && len > 0, "bad arguments");
1793   if (CanonicalizeEntry != NULL) {
1794     JavaThread* THREAD = JavaThread::current();
1795     JNIEnv* env = THREAD->jni_environment();
1796     ResourceMark rm(THREAD);
1797 
1798     // os::native_path writes into orig_copy
1799     char* orig_copy = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, strlen(orig)+1);
1800     strcpy(orig_copy, orig);
1801     if ((CanonicalizeEntry)(env, os::native_path(orig_copy), out, len) < 0) {
1802       return false;
1803     }
1804   } else {
1805     // On JDK 1.2.2 the Canonicalize does not exist, so just do nothing
1806     strncpy(out, orig, len);
1807     out[len - 1] = '\0';
1808   }
1809   return true;
1810 }
1811 
1812 void ClassLoader::create_javabase() {
1813   Thread* THREAD = Thread::current();
1814 
1815   // Create java.base's module entry for the boot
1816   // class loader prior to loading j.l.Ojbect.
1817   ClassLoaderData* null_cld = ClassLoaderData::the_null_class_loader_data();
1818 
1819   // Get module entry table
1820   ModuleEntryTable* null_cld_modules = null_cld->modules();
1821   if (null_cld_modules == NULL) {
1822     vm_exit_during_initialization("No ModuleEntryTable for the boot class loader");
1823   }
1824 
1825   {
1826     MutexLocker ml(Module_lock, THREAD);
1827     ModuleEntry* jb_module = null_cld_modules->locked_create_entry_or_null(Handle(),
1828                                false, vmSymbols::java_base(), NULL, NULL, null_cld);
1829     if (jb_module == NULL) {
1830       vm_exit_during_initialization("Unable to create ModuleEntry for " JAVA_BASE_NAME);
1831     }
1832     ModuleEntryTable::set_javabase_moduleEntry(jb_module);
1833   }
1834 }
1835 
1836 #ifndef PRODUCT
1837 
1838 // CompileTheWorld
1839 //
1840 // Iterates over all class path entries and forces compilation of all methods
1841 // in all classes found. Currently, only zip/jar archives are searched.
1842 //
1843 // The classes are loaded by the Java level bootstrap class loader, and the
1844 // initializer is called. If DelayCompilationDuringStartup is true (default),
1845 // the interpreter will run the initialization code. Note that forcing
1846 // initialization in this way could potentially lead to initialization order
1847 // problems, in which case we could just force the initialization bit to be set.
1848 
1849 
1850 // We need to iterate over the contents of a zip/jar file, so we replicate the
1851 // jzcell and jzfile definitions from zip_util.h but rename jzfile to real_jzfile,
1852 // since jzfile already has a void* definition.
1853 //
1854 // Note that this is only used in debug mode.
1855 //
1856 // HotSpot integration note:
1857 // Matches zip_util.h 1.14 99/06/01 from jdk1.3 beta H build
1858 
1859 
1860 // JDK 1.3 version
1861 typedef struct real_jzentry {         /* Zip file entry */
1862     char *name;                 /* entry name */
1863     jint time;                  /* modification time */
1864     jint size;                  /* size of uncompressed data */
1865     jint csize;                 /* size of compressed data (zero if uncompressed) */
1866     jint crc;                   /* crc of uncompressed data */
1867     char *comment;              /* optional zip file comment */
1868     jbyte *extra;               /* optional extra data */
1869     jint pos;                   /* position of LOC header (if negative) or data */
1870 } real_jzentry;
1871 
1872 typedef struct real_jzfile {  /* Zip file */
1873     char *name;                 /* zip file name */
1874     jint refs;                  /* number of active references */
1875     jint fd;                    /* open file descriptor */
1876     void *lock;                 /* read lock */
1877     char *comment;              /* zip file comment */
1878     char *msg;                  /* zip error message */
1879     void *entries;              /* array of hash cells */
1880     jint total;                 /* total number of entries */
1881     unsigned short *table;      /* Hash chain heads: indexes into entries */
1882     jint tablelen;              /* number of hash eads */
1883     real_jzfile *next;        /* next zip file in search list */
1884     jzentry *cache;             /* we cache the most recently freed jzentry */
1885     /* Information on metadata names in META-INF directory */
1886     char **metanames;           /* array of meta names (may have null names) */
1887     jint metacount;             /* number of slots in metanames array */
1888     /* If there are any per-entry comments, they are in the comments array */
1889     char **comments;
1890 } real_jzfile;
1891 
1892 void ClassPathDirEntry::compile_the_world(Handle loader, TRAPS) {
1893   // For now we only compile all methods in all classes in zip/jar files
1894   tty->print_cr("CompileTheWorld : Skipped classes in %s", _dir);
1895   tty->cr();
1896 }
1897 
1898 void ClassPathZipEntry::compile_the_world(Handle loader, TRAPS) {
1899   real_jzfile* zip = (real_jzfile*) _zip;
1900   tty->print_cr("CompileTheWorld : Compiling all classes in %s", zip->name);
1901   tty->cr();
1902   // Iterate over all entries in zip file
1903   for (int n = 0; ; n++) {
1904     real_jzentry * ze = (real_jzentry *)((*GetNextEntry)(_zip, n));
1905     if (ze == NULL) break;
1906     ClassLoader::compile_the_world_in(ze->name, loader, CHECK);
1907   }
1908   if (HAS_PENDING_EXCEPTION) {
1909     if (PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())) {
1910       CLEAR_PENDING_EXCEPTION;
1911       tty->print_cr("\nCompileTheWorld : Ran out of memory\n");
1912       tty->print_cr("Increase class metadata storage if a limit was set");
1913     } else {
1914       tty->print_cr("\nCompileTheWorld : Unexpected exception occurred\n");
1915     }
1916   }
1917 }
1918 
1919 void ClassLoader::compile_the_world() {
1920   EXCEPTION_MARK;
1921   HandleMark hm(THREAD);
1922   ResourceMark rm(THREAD);
1923 
1924   assert(has_jrt_entry(), "Compile The World not supported with exploded module build");
1925 
1926   // Find bootstrap loader
1927   Handle system_class_loader (THREAD, SystemDictionary::java_system_loader());
1928   jlong start = os::javaTimeMillis();
1929 
1930   // Compile the world for the modular java runtime image
1931   _jrt_entry->compile_the_world(system_class_loader, CATCH);
1932 
1933   // Iterate over all bootstrap class path appended entries
1934   ClassPathEntry* e = _first_append_entry;
1935   while (e != NULL) {
1936     assert(!e->is_modules_image(), "A modular java runtime image is present on the list of appended entries");
1937     e->compile_the_world(system_class_loader, CATCH);
1938     e = e->next();
1939   }
1940   jlong end = os::javaTimeMillis();
1941   tty->print_cr("CompileTheWorld : Done (%d classes, %d methods, " JLONG_FORMAT " ms)",
1942                 _compile_the_world_class_counter, _compile_the_world_method_counter, (end - start));
1943   {
1944     // Print statistics as if before normal exit:
1945     extern void print_statistics();
1946     print_statistics();
1947   }
1948   vm_exit(0);
1949 }
1950 
1951 int ClassLoader::_compile_the_world_class_counter = 0;
1952 int ClassLoader::_compile_the_world_method_counter = 0;
1953 static int _codecache_sweep_counter = 0;
1954 
1955 // Filter out all exceptions except OOMs
1956 static void clear_pending_exception_if_not_oom(TRAPS) {
1957   if (HAS_PENDING_EXCEPTION &&
1958       !PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())) {
1959     CLEAR_PENDING_EXCEPTION;
1960   }
1961   // The CHECK at the caller will propagate the exception out
1962 }
1963 
1964 /**
1965  * Returns if the given method should be compiled when doing compile-the-world.
1966  *
1967  * TODO:  This should be a private method in a CompileTheWorld class.
1968  */
1969 static bool can_be_compiled(const methodHandle& m, int comp_level) {
1970   assert(CompileTheWorld, "must be");
1971 
1972   // It's not valid to compile a native wrapper for MethodHandle methods
1973   // that take a MemberName appendix since the bytecode signature is not
1974   // correct.
1975   vmIntrinsics::ID iid = m->intrinsic_id();
1976   if (MethodHandles::is_signature_polymorphic(iid) && MethodHandles::has_member_arg(iid)) {
1977     return false;
1978   }
1979 
1980   return CompilationPolicy::can_be_compiled(m, comp_level);
1981 }
1982 
1983 void ClassLoader::compile_the_world_in(char* name, Handle loader, TRAPS) {
1984   if (string_ends_with(name, ".class")) {
1985     // We have a .class file
1986     int len = (int)strlen(name);
1987     char buffer[2048];
1988     strncpy(buffer, name, len - 6);
1989     buffer[len-6] = 0;
1990     // If the file has a period after removing .class, it's not really a
1991     // valid class file.  The class loader will check everything else.
1992     if (strchr(buffer, '.') == NULL) {
1993       _compile_the_world_class_counter++;
1994       if (_compile_the_world_class_counter > CompileTheWorldStopAt) return;
1995 
1996       // Construct name without extension
1997       TempNewSymbol sym = SymbolTable::new_symbol(buffer, CHECK);
1998       // Use loader to load and initialize class
1999       Klass* k = SystemDictionary::resolve_or_null(sym, loader, Handle(), THREAD);
2000       if (k != NULL && !HAS_PENDING_EXCEPTION) {
2001         k->initialize(THREAD);
2002       }
2003       bool exception_occurred = HAS_PENDING_EXCEPTION;
2004       clear_pending_exception_if_not_oom(CHECK);
2005       if (CompileTheWorldPreloadClasses && k != NULL) {
2006         InstanceKlass* ik = InstanceKlass::cast(k);
2007         ConstantPool::preload_and_initialize_all_classes(ik->constants(), THREAD);
2008         if (HAS_PENDING_EXCEPTION) {
2009           // If something went wrong in preloading we just ignore it
2010           clear_pending_exception_if_not_oom(CHECK);
2011           tty->print_cr("Preloading failed for (%d) %s", _compile_the_world_class_counter, buffer);
2012         }
2013       }
2014 
2015       if (_compile_the_world_class_counter >= CompileTheWorldStartAt) {
2016         if (k == NULL || exception_occurred) {
2017           // If something went wrong (e.g. ExceptionInInitializerError) we skip this class
2018           tty->print_cr("CompileTheWorld (%d) : Skipping %s", _compile_the_world_class_counter, buffer);
2019         } else {
2020           tty->print_cr("CompileTheWorld (%d) : %s", _compile_the_world_class_counter, buffer);
2021           // Preload all classes to get around uncommon traps
2022           // Iterate over all methods in class
2023           int comp_level = CompilationPolicy::policy()->initial_compile_level();
2024           InstanceKlass* ik = InstanceKlass::cast(k);
2025           for (int n = 0; n < ik->methods()->length(); n++) {
2026             methodHandle m (THREAD, ik->methods()->at(n));
2027             if (can_be_compiled(m, comp_level)) {
2028               if (++_codecache_sweep_counter == CompileTheWorldSafepointInterval) {
2029                 // Give sweeper a chance to keep up with CTW
2030                 VM_CTWThreshold op;
2031                 VMThread::execute(&op);
2032                 _codecache_sweep_counter = 0;
2033               }
2034               // Force compilation
2035               CompileBroker::compile_method(m, InvocationEntryBci, comp_level,
2036                                             methodHandle(), 0, CompileTask::Reason_CTW, THREAD);
2037               if (HAS_PENDING_EXCEPTION) {
2038                 clear_pending_exception_if_not_oom(CHECK);
2039                 tty->print_cr("CompileTheWorld (%d) : Skipping method: %s", _compile_the_world_class_counter, m->name_and_sig_as_C_string());
2040               } else {
2041                 _compile_the_world_method_counter++;
2042               }
2043               if (TieredCompilation && TieredStopAtLevel >= CompLevel_full_optimization) {
2044                 // Clobber the first compile and force second tier compilation
2045                 CompiledMethod* nm = m->code();
2046                 if (nm != NULL && !m->is_method_handle_intrinsic()) {
2047                   // Throw out the code so that the code cache doesn't fill up
2048                   nm->make_not_entrant();
2049                 }
2050                 CompileBroker::compile_method(m, InvocationEntryBci, CompLevel_full_optimization,
2051                                               methodHandle(), 0, CompileTask::Reason_CTW, THREAD);
2052                 if (HAS_PENDING_EXCEPTION) {
2053                   clear_pending_exception_if_not_oom(CHECK);
2054                   tty->print_cr("CompileTheWorld (%d) : Skipping method: %s", _compile_the_world_class_counter, m->name_and_sig_as_C_string());
2055                 } else {
2056                   _compile_the_world_method_counter++;
2057                 }
2058               }
2059             } else {
2060               tty->print_cr("CompileTheWorld (%d) : Skipping method: %s", _compile_the_world_class_counter, m->name_and_sig_as_C_string());
2061             }
2062 
2063             CompiledMethod* nm = m->code();
2064             if (nm != NULL && !m->is_method_handle_intrinsic()) {
2065               // Throw out the code so that the code cache doesn't fill up
2066               nm->make_not_entrant();
2067             }
2068           }
2069         }
2070       }
2071     }
2072   }
2073 }
2074 
2075 #endif //PRODUCT
2076 
2077 // Please keep following two functions at end of this file. With them placed at top or in middle of the file,
2078 // they could get inlined by agressive compiler, an unknown trick, see bug 6966589.
2079 void PerfClassTraceTime::initialize() {
2080   if (!UsePerfData) return;
2081 
2082   if (_eventp != NULL) {
2083     // increment the event counter
2084     _eventp->inc();
2085   }
2086 
2087   // stop the current active thread-local timer to measure inclusive time
2088   _prev_active_event = -1;
2089   for (int i=0; i < EVENT_TYPE_COUNT; i++) {
2090      if (_timers[i].is_active()) {
2091        assert(_prev_active_event == -1, "should have only one active timer");
2092        _prev_active_event = i;
2093        _timers[i].stop();
2094      }
2095   }
2096 
2097   if (_recursion_counters == NULL || (_recursion_counters[_event_type])++ == 0) {
2098     // start the inclusive timer if not recursively called
2099     _t.start();
2100   }
2101 
2102   // start thread-local timer of the given event type
2103    if (!_timers[_event_type].is_active()) {
2104     _timers[_event_type].start();
2105   }
2106 }
2107 
2108 PerfClassTraceTime::~PerfClassTraceTime() {
2109   if (!UsePerfData) return;
2110 
2111   // stop the thread-local timer as the event completes
2112   // and resume the thread-local timer of the event next on the stack
2113   _timers[_event_type].stop();
2114   jlong selftime = _timers[_event_type].ticks();
2115 
2116   if (_prev_active_event >= 0) {
2117     _timers[_prev_active_event].start();
2118   }
2119 
2120   if (_recursion_counters != NULL && --(_recursion_counters[_event_type]) > 0) return;
2121 
2122   // increment the counters only on the leaf call
2123   _t.stop();
2124   _timep->inc(_t.ticks());
2125   if (_selftimep != NULL) {
2126     _selftimep->inc(selftime);
2127   }
2128   // add all class loading related event selftime to the accumulated time counter
2129   ClassLoader::perf_accumulated_time()->inc(selftime);
2130 
2131   // reset the timer
2132   _timers[_event_type].reset();
2133 }