1 /*
   2  * Copyright (c) 2003, 2024, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "cds/archiveBuilder.hpp"
  27 #include "cds/archiveHeapLoader.inline.hpp"
  28 #include "cds/archiveHeapWriter.hpp"
  29 #include "cds/archiveUtils.inline.hpp"
  30 #include "cds/cds_globals.hpp"
  31 #include "cds/cdsConfig.hpp"
  32 #include "cds/dynamicArchive.hpp"
  33 #include "cds/filemap.hpp"
  34 #include "cds/heapShared.hpp"
  35 #include "cds/metaspaceShared.hpp"
  36 #include "classfile/altHashing.hpp"
  37 #include "classfile/classFileStream.hpp"
  38 #include "classfile/classLoader.hpp"
  39 #include "classfile/classLoader.inline.hpp"
  40 #include "classfile/classLoaderData.inline.hpp"
  41 #include "classfile/classLoaderExt.hpp"
  42 #include "classfile/symbolTable.hpp"
  43 #include "classfile/systemDictionaryShared.hpp"
  44 #include "classfile/vmClasses.hpp"
  45 #include "classfile/vmSymbols.hpp"
  46 #include "jvm.h"
  47 #include "logging/log.hpp"
  48 #include "logging/logMessage.hpp"
  49 #include "logging/logStream.hpp"
  50 #include "memory/iterator.inline.hpp"
  51 #include "memory/metadataFactory.hpp"
  52 #include "memory/metaspaceClosure.hpp"
  53 #include "memory/oopFactory.hpp"
  54 #include "memory/universe.hpp"
  55 #include "nmt/memTracker.hpp"
  56 #include "oops/compressedOops.hpp"
  57 #include "oops/compressedOops.inline.hpp"
  58 #include "oops/objArrayOop.hpp"
  59 #include "oops/oop.inline.hpp"
  60 #include "prims/jvmtiExport.hpp"
  61 #include "runtime/arguments.hpp"
  62 #include "runtime/globals_extension.hpp"
  63 #include "runtime/java.hpp"
  64 #include "runtime/mutexLocker.hpp"
  65 #include "runtime/os.hpp"
  66 #include "runtime/vm_version.hpp"
  67 #include "utilities/align.hpp"
  68 #include "utilities/bitMap.inline.hpp"
  69 #include "utilities/classpathStream.hpp"
  70 #include "utilities/defaultStream.hpp"
  71 #include "utilities/ostream.hpp"
  72 #if INCLUDE_G1GC
  73 #include "gc/g1/g1CollectedHeap.hpp"
  74 #include "gc/g1/g1HeapRegion.hpp"
  75 #endif
  76 
  77 # include <sys/stat.h>
  78 # include <errno.h>
  79 
  80 #ifndef O_BINARY       // if defined (Win32) use binary files.
  81 #define O_BINARY 0     // otherwise do nothing.
  82 #endif
  83 
  84 // Fill in the fileMapInfo structure with data about this VM instance.
  85 
  86 // This method copies the vm version info into header_version.  If the version is too
  87 // long then a truncated version, which has a hash code appended to it, is copied.
  88 //
  89 // Using a template enables this method to verify that header_version is an array of
  90 // length JVM_IDENT_MAX.  This ensures that the code that writes to the CDS file and
  91 // the code that reads the CDS file will both use the same size buffer.  Hence, will
  92 // use identical truncation.  This is necessary for matching of truncated versions.
  93 template <int N> static void get_header_version(char (&header_version) [N]) {
  94   assert(N == JVM_IDENT_MAX, "Bad header_version size");
  95 
  96   const char *vm_version = VM_Version::internal_vm_info_string();
  97   const int version_len = (int)strlen(vm_version);
  98 
  99   memset(header_version, 0, JVM_IDENT_MAX);
 100 
 101   if (version_len < (JVM_IDENT_MAX-1)) {
 102     strcpy(header_version, vm_version);
 103 
 104   } else {
 105     // Get the hash value.  Use a static seed because the hash needs to return the same
 106     // value over multiple jvm invocations.
 107     uint32_t hash = AltHashing::halfsiphash_32(8191, (const uint8_t*)vm_version, version_len);
 108 
 109     // Truncate the ident, saving room for the 8 hex character hash value.
 110     strncpy(header_version, vm_version, JVM_IDENT_MAX-9);
 111 
 112     // Append the hash code as eight hex digits.
 113     os::snprintf_checked(&header_version[JVM_IDENT_MAX-9], 9, "%08x", hash);
 114     header_version[JVM_IDENT_MAX-1] = 0;  // Null terminate.
 115   }
 116 
 117   assert(header_version[JVM_IDENT_MAX-1] == 0, "must be");
 118 }
 119 
 120 FileMapInfo::FileMapInfo(const char* full_path, bool is_static) :
 121   _is_static(is_static), _file_open(false), _is_mapped(false), _fd(-1), _file_offset(0),
 122   _full_path(full_path), _base_archive_name(nullptr), _header(nullptr) {
 123   if (_is_static) {
 124     assert(_current_info == nullptr, "must be singleton"); // not thread safe
 125     _current_info = this;
 126   } else {
 127     assert(_dynamic_archive_info == nullptr, "must be singleton"); // not thread safe
 128     _dynamic_archive_info = this;
 129   }
 130 }
 131 
 132 FileMapInfo::~FileMapInfo() {
 133   if (_is_static) {
 134     assert(_current_info == this, "must be singleton"); // not thread safe
 135     _current_info = nullptr;
 136   } else {
 137     assert(_dynamic_archive_info == this, "must be singleton"); // not thread safe
 138     _dynamic_archive_info = nullptr;
 139   }
 140 
 141   if (_header != nullptr) {
 142     os::free(_header);
 143   }
 144 
 145   if (_file_open) {
 146     ::close(_fd);
 147   }
 148 }
 149 
 150 void FileMapInfo::populate_header(size_t core_region_alignment) {
 151   assert(_header == nullptr, "Sanity check");
 152   size_t c_header_size;
 153   size_t header_size;
 154   size_t base_archive_name_size = 0;
 155   size_t base_archive_name_offset = 0;
 156   size_t longest_common_prefix_size = 0;
 157   if (is_static()) {
 158     c_header_size = sizeof(FileMapHeader);
 159     header_size = c_header_size;
 160   } else {
 161     // dynamic header including base archive name for non-default base archive
 162     c_header_size = sizeof(DynamicArchiveHeader);
 163     header_size = c_header_size;
 164 
 165     const char* default_base_archive_name = CDSConfig::default_archive_path();
 166     const char* current_base_archive_name = CDSConfig::static_archive_path();
 167     if (!os::same_files(current_base_archive_name, default_base_archive_name)) {
 168       base_archive_name_size = strlen(current_base_archive_name) + 1;
 169       header_size += base_archive_name_size;
 170       base_archive_name_offset = c_header_size;
 171     }
 172   }
 173   ResourceMark rm;
 174   GrowableArray<const char*>* app_cp_array = create_dumptime_app_classpath_array();
 175   int len = app_cp_array->length();
 176   longest_common_prefix_size = longest_common_app_classpath_prefix_len(len, app_cp_array);
 177   _header = (FileMapHeader*)os::malloc(header_size, mtInternal);
 178   memset((void*)_header, 0, header_size);
 179   _header->populate(this,
 180                     core_region_alignment,
 181                     header_size,
 182                     base_archive_name_size,
 183                     base_archive_name_offset,
 184                     longest_common_prefix_size);
 185 }
 186 
 187 void FileMapHeader::populate(FileMapInfo *info, size_t core_region_alignment,
 188                              size_t header_size, size_t base_archive_name_size,
 189                              size_t base_archive_name_offset, size_t common_app_classpath_prefix_size) {
 190   // 1. We require _generic_header._magic to be at the beginning of the file
 191   // 2. FileMapHeader also assumes that _generic_header is at the beginning of the file
 192   assert(offset_of(FileMapHeader, _generic_header) == 0, "must be");
 193   set_header_size((unsigned int)header_size);
 194   set_base_archive_name_offset((unsigned int)base_archive_name_offset);
 195   set_base_archive_name_size((unsigned int)base_archive_name_size);
 196   set_common_app_classpath_prefix_size((unsigned int)common_app_classpath_prefix_size);
 197   set_magic(CDSConfig::is_dumping_dynamic_archive() ? CDS_DYNAMIC_ARCHIVE_MAGIC : CDS_ARCHIVE_MAGIC);
 198   set_version(CURRENT_CDS_ARCHIVE_VERSION);
 199 
 200   if (!info->is_static() && base_archive_name_size != 0) {
 201     // copy base archive name
 202     copy_base_archive_name(CDSConfig::static_archive_path());
 203   }
 204   _core_region_alignment = core_region_alignment;
 205   _obj_alignment = ObjectAlignmentInBytes;
 206   _compact_strings = CompactStrings;
 207   if (CDSConfig::is_dumping_heap()) {
 208     _narrow_oop_mode = CompressedOops::mode();
 209     _narrow_oop_base = CompressedOops::base();
 210     _narrow_oop_shift = CompressedOops::shift();
 211   }
 212   _compressed_oops = UseCompressedOops;
 213   _compressed_class_ptrs = UseCompressedClassPointers;
 214   _use_secondary_supers_table = UseSecondarySupersTable;
 215   _max_heap_size = MaxHeapSize;
 216   _use_optimized_module_handling = CDSConfig::is_using_optimized_module_handling();

 217   _has_full_module_graph = CDSConfig::is_dumping_full_module_graph();





 218 
 219   // The following fields are for sanity checks for whether this archive
 220   // will function correctly with this JVM and the bootclasspath it's
 221   // invoked with.
 222 
 223   // JVM version string ... changes on each build.
 224   get_header_version(_jvm_ident);
 225 
 226   _app_class_paths_start_index = ClassLoaderExt::app_class_paths_start_index();
 227   _app_module_paths_start_index = ClassLoaderExt::app_module_paths_start_index();
 228   _max_used_path_index = ClassLoaderExt::max_used_path_index();
 229   _num_module_paths = ClassLoader::num_module_path_entries();
 230 
 231   _verify_local = BytecodeVerificationLocal;
 232   _verify_remote = BytecodeVerificationRemote;
 233   _has_platform_or_app_classes = ClassLoaderExt::has_platform_or_app_classes();
 234   _has_non_jar_in_classpath = ClassLoaderExt::has_non_jar_in_classpath();
 235   _requested_base_address = (char*)SharedBaseAddress;
 236   _mapped_base_address = (char*)SharedBaseAddress;
 237   _allow_archiving_with_java_agent = AllowArchivingWithJavaAgent;
 238 
 239   if (!CDSConfig::is_dumping_dynamic_archive()) {
 240     set_shared_path_table(info->_shared_path_table);
 241   }
 242 }
 243 
 244 void FileMapHeader::copy_base_archive_name(const char* archive) {
 245   assert(base_archive_name_size() != 0, "_base_archive_name_size not set");
 246   assert(base_archive_name_offset() != 0, "_base_archive_name_offset not set");
 247   assert(header_size() > sizeof(*this), "_base_archive_name_size not included in header size?");
 248   memcpy((char*)this + base_archive_name_offset(), archive, base_archive_name_size());
 249 }
 250 
 251 void FileMapHeader::print(outputStream* st) {
 252   ResourceMark rm;
 253 
 254   st->print_cr("- magic:                          0x%08x", magic());
 255   st->print_cr("- crc:                            0x%08x", crc());
 256   st->print_cr("- version:                        0x%x", version());
 257   st->print_cr("- header_size:                    " UINT32_FORMAT, header_size());
 258   st->print_cr("- common_app_classpath_size:      " UINT32_FORMAT, common_app_classpath_prefix_size());
 259   st->print_cr("- base_archive_name_offset:       " UINT32_FORMAT, base_archive_name_offset());
 260   st->print_cr("- base_archive_name_size:         " UINT32_FORMAT, base_archive_name_size());
 261 
 262   for (int i = 0; i < NUM_CDS_REGIONS; i++) {
 263     FileMapRegion* r = region_at(i);
 264     r->print(st, i);
 265   }
 266   st->print_cr("============ end regions ======== ");
 267 
 268   st->print_cr("- core_region_alignment:          " SIZE_FORMAT, _core_region_alignment);
 269   st->print_cr("- obj_alignment:                  %d", _obj_alignment);
 270   st->print_cr("- narrow_oop_base:                " INTPTR_FORMAT, p2i(_narrow_oop_base));
 271   st->print_cr("- narrow_oop_shift                %d", _narrow_oop_shift);
 272   st->print_cr("- compact_strings:                %d", _compact_strings);
 273   st->print_cr("- max_heap_size:                  " UINTX_FORMAT, _max_heap_size);
 274   st->print_cr("- narrow_oop_mode:                %d", _narrow_oop_mode);
 275   st->print_cr("- compressed_oops:                %d", _compressed_oops);
 276   st->print_cr("- compressed_class_ptrs:          %d", _compressed_class_ptrs);
 277   st->print_cr("- use_secondary_supers_table:     %d", _use_secondary_supers_table);
 278   st->print_cr("- cloned_vtables_offset:          " SIZE_FORMAT_X, _cloned_vtables_offset);
 279   st->print_cr("- serialized_data_offset:         " SIZE_FORMAT_X, _serialized_data_offset);
 280   st->print_cr("- jvm_ident:                      %s", _jvm_ident);
 281   st->print_cr("- shared_path_table_offset:       " SIZE_FORMAT_X, _shared_path_table_offset);
 282   st->print_cr("- app_class_paths_start_index:    %d", _app_class_paths_start_index);
 283   st->print_cr("- app_module_paths_start_index:   %d", _app_module_paths_start_index);
 284   st->print_cr("- num_module_paths:               %d", _num_module_paths);
 285   st->print_cr("- max_used_path_index:            %d", _max_used_path_index);
 286   st->print_cr("- verify_local:                   %d", _verify_local);
 287   st->print_cr("- verify_remote:                  %d", _verify_remote);
 288   st->print_cr("- has_platform_or_app_classes:    %d", _has_platform_or_app_classes);
 289   st->print_cr("- has_non_jar_in_classpath:       %d", _has_non_jar_in_classpath);
 290   st->print_cr("- requested_base_address:         " INTPTR_FORMAT, p2i(_requested_base_address));
 291   st->print_cr("- mapped_base_address:            " INTPTR_FORMAT, p2i(_mapped_base_address));
 292   st->print_cr("- heap_root_segments.roots_count: %d" , _heap_root_segments.roots_count());
 293   st->print_cr("- heap_root_segments.base_offset: " SIZE_FORMAT_X, _heap_root_segments.base_offset());
 294   st->print_cr("- heap_root_segments.count:       " SIZE_FORMAT, _heap_root_segments.count());
 295   st->print_cr("- heap_root_segments.max_size_elems: %d", _heap_root_segments.max_size_in_elems());
 296   st->print_cr("- heap_root_segments.max_size_bytes: %d", _heap_root_segments.max_size_in_bytes());
 297   st->print_cr("- _heap_oopmap_start_pos:         " SIZE_FORMAT, _heap_oopmap_start_pos);
 298   st->print_cr("- _heap_ptrmap_start_pos:         " SIZE_FORMAT, _heap_ptrmap_start_pos);
 299   st->print_cr("- _rw_ptrmap_start_pos:           " SIZE_FORMAT, _rw_ptrmap_start_pos);
 300   st->print_cr("- _ro_ptrmap_start_pos:           " SIZE_FORMAT, _ro_ptrmap_start_pos);
 301   st->print_cr("- allow_archiving_with_java_agent:%d", _allow_archiving_with_java_agent);
 302   st->print_cr("- use_optimized_module_handling:  %d", _use_optimized_module_handling);
 303   st->print_cr("- has_full_module_graph           %d", _has_full_module_graph);





 304 }
 305 
 306 void SharedClassPathEntry::init_as_non_existent(const char* path, TRAPS) {
 307   _type = non_existent_entry;
 308   set_name(path, CHECK);
 309 }
 310 
 311 void SharedClassPathEntry::init(bool is_modules_image,
 312                                 bool is_module_path,
 313                                 ClassPathEntry* cpe, TRAPS) {
 314   assert(CDSConfig::is_dumping_archive(), "sanity");
 315   _timestamp = 0;
 316   _filesize  = 0;
 317   _from_class_path_attr = false;
 318 
 319   struct stat st;
 320   if (os::stat(cpe->name(), &st) == 0) {
 321     if ((st.st_mode & S_IFMT) == S_IFDIR) {
 322       _type = dir_entry;
 323     } else {
 324       // The timestamp of the modules_image is not checked at runtime.
 325       if (is_modules_image) {
 326         _type = modules_image_entry;
 327       } else {
 328         _type = jar_entry;
 329         _timestamp = st.st_mtime;
 330         _from_class_path_attr = cpe->from_class_path_attr();
 331       }
 332       _filesize = st.st_size;
 333       _is_module_path = is_module_path;
 334     }
 335   } else {
 336     // The file/dir must exist, or it would not have been added
 337     // into ClassLoader::classpath_entry().
 338     //
 339     // If we can't access a jar file in the boot path, then we can't
 340     // make assumptions about where classes get loaded from.
 341     log_error(cds)("Unable to open file %s.", cpe->name());
 342     MetaspaceShared::unrecoverable_loading_error();
 343   }
 344 
 345   // No need to save the name of the module file, as it will be computed at run time
 346   // to allow relocation of the JDK directory.
 347   const char* name = is_modules_image  ? "" : cpe->name();
 348   set_name(name, CHECK);
 349 }
 350 
 351 void SharedClassPathEntry::set_name(const char* name, TRAPS) {
 352   size_t len = strlen(name) + 1;
 353   _name = MetadataFactory::new_array<char>(ClassLoaderData::the_null_class_loader_data(), (int)len, CHECK);
 354   strcpy(_name->data(), name);
 355 }
 356 
 357 void SharedClassPathEntry::copy_from(SharedClassPathEntry* ent, ClassLoaderData* loader_data, TRAPS) {
 358   assert(ent != nullptr, "sanity");
 359   _type = ent->_type;
 360   _is_module_path = ent->_is_module_path;
 361   _timestamp = ent->_timestamp;
 362   _filesize = ent->_filesize;
 363   _from_class_path_attr = ent->_from_class_path_attr;
 364   set_name(ent->name(), CHECK);
 365 
 366   if (ent->is_jar() && ent->manifest() != nullptr) {
 367     Array<u1>* buf = MetadataFactory::new_array<u1>(loader_data,
 368                                                     ent->manifest_size(),
 369                                                     CHECK);
 370     char* p = (char*)(buf->data());
 371     memcpy(p, ent->manifest(), ent->manifest_size());
 372     set_manifest(buf);
 373   }
 374 }
 375 
 376 const char* SharedClassPathEntry::name() const {
 377   if (CDSConfig::is_using_archive() && is_modules_image()) {
 378     // In order to validate the runtime modules image file size against the archived
 379     // size information, we need to obtain the runtime modules image path. The recorded
 380     // dump time modules image path in the archive may be different from the runtime path
 381     // if the JDK image has beed moved after generating the archive.
 382     return ClassLoader::get_jrt_entry()->name();
 383   } else {
 384     return _name->data();
 385   }
 386 }
 387 
 388 bool SharedClassPathEntry::validate(bool is_class_path) const {
 389   assert(CDSConfig::is_using_archive(), "runtime only");
 390 
 391   struct stat st;
 392   const char* name = this->name();
 393 
 394   bool ok = true;
 395   log_info(class, path)("checking shared classpath entry: %s", name);
 396   if (os::stat(name, &st) != 0 && is_class_path) {
 397     // If the archived module path entry does not exist at runtime, it is not fatal
 398     // (no need to invalid the shared archive) because the shared runtime visibility check
 399     // filters out any archived module classes that do not have a matching runtime
 400     // module path location.
 401     log_warning(cds)("Required classpath entry does not exist: %s", name);
 402     ok = false;
 403   } else if (is_dir()) {
 404     if (!os::dir_is_empty(name)) {
 405       log_warning(cds)("directory is not empty: %s", name);
 406       ok = false;
 407     }
 408   } else {
 409     bool size_differs = _filesize != st.st_size;
 410     bool time_differs = has_timestamp() && _timestamp != st.st_mtime;
 411     if (time_differs || size_differs) {
 412       ok = false;
 413       if (PrintSharedArchiveAndExit) {
 414         log_warning(cds)(time_differs ? "Timestamp mismatch" : "File size mismatch");
 415       } else {
 416         const char* bad_file_msg = "This file is not the one used while building the shared archive file:";
 417         log_warning(cds)("%s %s", bad_file_msg, name);
 418         if (!log_is_enabled(Info, cds)) {
 419           log_warning(cds)("%s %s", bad_file_msg, name);
 420         }
 421         if (time_differs) {
 422           log_warning(cds)("%s timestamp has changed.", name);
 423         }
 424         if (size_differs) {
 425           log_warning(cds)("%s size has changed.", name);
 426         }
 427       }
 428     }
 429   }
 430 
 431   if (PrintSharedArchiveAndExit && !ok) {
 432     // If PrintSharedArchiveAndExit is enabled, don't report failure to the
 433     // caller. Please see above comments for more details.
 434     ok = true;
 435     MetaspaceShared::set_archive_loading_failed();
 436   }
 437   return ok;
 438 }
 439 
 440 bool SharedClassPathEntry::check_non_existent() const {
 441   assert(_type == non_existent_entry, "must be");
 442   log_info(class, path)("should be non-existent: %s", name());
 443   struct stat st;
 444   if (os::stat(name(), &st) != 0) {
 445     log_info(class, path)("ok");
 446     return true; // file doesn't exist
 447   } else {
 448     return false;
 449   }
 450 }
 451 
 452 void SharedClassPathEntry::metaspace_pointers_do(MetaspaceClosure* it) {
 453   it->push(&_name);
 454   it->push(&_manifest);
 455 }
 456 
 457 void SharedPathTable::metaspace_pointers_do(MetaspaceClosure* it) {
 458   it->push(&_entries);
 459 }
 460 
 461 void SharedPathTable::dumptime_init(ClassLoaderData* loader_data, TRAPS) {
 462   const int num_entries =
 463     ClassLoader::num_boot_classpath_entries() +
 464     ClassLoader::num_app_classpath_entries() +
 465     ClassLoader::num_module_path_entries() +
 466     FileMapInfo::num_non_existent_class_paths();
 467   _entries = MetadataFactory::new_array<SharedClassPathEntry*>(loader_data, num_entries, CHECK);
 468   for (int i = 0; i < num_entries; i++) {
 469     SharedClassPathEntry* ent =
 470       new (loader_data, SharedClassPathEntry::size(), MetaspaceObj::SharedClassPathEntryType, THREAD) SharedClassPathEntry;
 471     _entries->at_put(i, ent);
 472   }
 473 }
 474 
 475 void FileMapInfo::allocate_shared_path_table(TRAPS) {
 476   assert(CDSConfig::is_dumping_archive(), "sanity");
 477 
 478   ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
 479   ClassPathEntry* jrt = ClassLoader::get_jrt_entry();
 480 
 481   assert(jrt != nullptr,
 482          "No modular java runtime image present when allocating the CDS classpath entry table");
 483 
 484   _shared_path_table.dumptime_init(loader_data, CHECK);
 485 
 486   // 1. boot class path
 487   int i = 0;
 488   i = add_shared_classpaths(i, "boot",   jrt, CHECK);
 489   i = add_shared_classpaths(i, "app",    ClassLoader::app_classpath_entries(), CHECK);
 490   i = add_shared_classpaths(i, "module", ClassLoader::module_path_entries(), CHECK);
 491 
 492   for (int x = 0; x < num_non_existent_class_paths(); x++, i++) {
 493     const char* path = _non_existent_class_paths->at(x);
 494     shared_path(i)->init_as_non_existent(path, CHECK);
 495   }
 496 
 497   assert(i == _shared_path_table.size(), "number of shared path entry mismatch");
 498 }
 499 
 500 int FileMapInfo::add_shared_classpaths(int i, const char* which, ClassPathEntry *cpe, TRAPS) {
 501   while (cpe != nullptr) {
 502     bool is_jrt = (cpe == ClassLoader::get_jrt_entry());
 503     bool is_module_path = i >= ClassLoaderExt::app_module_paths_start_index();
 504     const char* type = (is_jrt ? "jrt" : (cpe->is_jar_file() ? "jar" : "dir"));
 505     log_info(class, path)("add %s shared path (%s) %s", which, type, cpe->name());
 506     SharedClassPathEntry* ent = shared_path(i);
 507     ent->init(is_jrt, is_module_path, cpe, CHECK_0);
 508     if (cpe->is_jar_file()) {
 509       update_jar_manifest(cpe, ent, CHECK_0);
 510     }
 511     if (is_jrt) {
 512       cpe = ClassLoader::get_next_boot_classpath_entry(cpe);
 513     } else {
 514       cpe = cpe->next();
 515     }
 516     i++;
 517   }
 518 
 519   return i;
 520 }
 521 
 522 void FileMapInfo::check_nonempty_dir_in_shared_path_table() {
 523   assert(CDSConfig::is_dumping_archive(), "sanity");
 524 
 525   bool has_nonempty_dir = false;
 526 
 527   int last = _shared_path_table.size() - 1;
 528   if (last > ClassLoaderExt::max_used_path_index()) {
 529      // no need to check any path beyond max_used_path_index
 530      last = ClassLoaderExt::max_used_path_index();
 531   }
 532 
 533   for (int i = 0; i <= last; i++) {
 534     SharedClassPathEntry *e = shared_path(i);
 535     if (e->is_dir()) {
 536       const char* path = e->name();
 537       if (!os::dir_is_empty(path)) {
 538         log_error(cds)("Error: non-empty directory '%s'", path);
 539         has_nonempty_dir = true;
 540       }
 541     }
 542   }
 543 
 544   if (has_nonempty_dir) {
 545     ClassLoader::exit_with_path_failure("Cannot have non-empty directory in paths", nullptr);
 546   }
 547 }
 548 
 549 void FileMapInfo::record_non_existent_class_path_entry(const char* path) {
 550   assert(CDSConfig::is_dumping_archive(), "sanity");
 551   log_info(class, path)("non-existent Class-Path entry %s", path);
 552   if (_non_existent_class_paths == nullptr) {
 553     _non_existent_class_paths = new (mtClass) GrowableArray<const char*>(10, mtClass);
 554   }
 555   _non_existent_class_paths->append(os::strdup(path));
 556 }
 557 
 558 int FileMapInfo::num_non_existent_class_paths() {
 559   assert(CDSConfig::is_dumping_archive(), "sanity");
 560   if (_non_existent_class_paths != nullptr) {
 561     return _non_existent_class_paths->length();
 562   } else {
 563     return 0;
 564   }
 565 }
 566 
 567 int FileMapInfo::get_module_shared_path_index(Symbol* location) {



 568   if (location->starts_with("jrt:", 4) && get_number_of_shared_paths() > 0) {
 569     assert(shared_path(0)->is_modules_image(), "first shared_path must be the modules image");
 570     return 0;
 571   }
 572 
 573   if (ClassLoaderExt::app_module_paths_start_index() >= get_number_of_shared_paths()) {
 574     // The archive(s) were created without --module-path option
 575     return -1;
 576   }
 577 
 578   if (!location->starts_with("file:", 5)) {
 579     return -1;
 580   }
 581 
 582   // skip_uri_protocol was also called during dump time -- see ClassLoaderExt::process_module_table()
 583   ResourceMark rm;
 584   const char* file = ClassLoader::uri_to_path(location->as_C_string());
 585   for (int i = ClassLoaderExt::app_module_paths_start_index(); i < get_number_of_shared_paths(); i++) {
 586     SharedClassPathEntry* ent = shared_path(i);
 587     if (!ent->is_non_existent()) {
 588       assert(ent->in_named_module(), "must be");
 589       bool cond = strcmp(file, ent->name()) == 0;
 590       log_debug(class, path)("get_module_shared_path_index (%d) %s : %s = %s", i,
 591                              location->as_C_string(), ent->name(), cond ? "same" : "different");
 592       if (cond) {
 593         return i;
 594       }
 595     }
 596   }
 597 
 598   return -1;
 599 }
 600 
 601 class ManifestStream: public ResourceObj {
 602   private:
 603   u1*   _buffer_start; // Buffer bottom
 604   u1*   _buffer_end;   // Buffer top (one past last element)
 605   u1*   _current;      // Current buffer position
 606 
 607  public:
 608   // Constructor
 609   ManifestStream(u1* buffer, int length) : _buffer_start(buffer),
 610                                            _current(buffer) {
 611     _buffer_end = buffer + length;
 612   }
 613 
 614   static bool is_attr(u1* attr, const char* name) {
 615     return strncmp((const char*)attr, name, strlen(name)) == 0;
 616   }
 617 
 618   static char* copy_attr(u1* value, size_t len) {
 619     char* buf = NEW_RESOURCE_ARRAY(char, len + 1);
 620     strncpy(buf, (char*)value, len);
 621     buf[len] = 0;
 622     return buf;
 623   }
 624 };
 625 
 626 void FileMapInfo::update_jar_manifest(ClassPathEntry *cpe, SharedClassPathEntry* ent, TRAPS) {
 627   ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
 628   ResourceMark rm(THREAD);
 629   jint manifest_size;
 630 
 631   assert(cpe->is_jar_file() && ent->is_jar(), "the shared class path entry is not a JAR file");
 632   char* manifest = ClassLoaderExt::read_manifest(THREAD, cpe, &manifest_size);
 633   if (manifest != nullptr) {
 634     ManifestStream* stream = new ManifestStream((u1*)manifest,
 635                                                 manifest_size);
 636     // Copy the manifest into the shared archive
 637     manifest = ClassLoaderExt::read_raw_manifest(THREAD, cpe, &manifest_size);
 638     Array<u1>* buf = MetadataFactory::new_array<u1>(loader_data,
 639                                                     manifest_size,
 640                                                     CHECK);
 641     char* p = (char*)(buf->data());
 642     memcpy(p, manifest, manifest_size);
 643     ent->set_manifest(buf);
 644   }
 645 }
 646 
 647 char* FileMapInfo::skip_first_path_entry(const char* path) {
 648   size_t path_sep_len = strlen(os::path_separator());
 649   char* p = strstr((char*)path, os::path_separator());
 650   if (p != nullptr) {
 651     debug_only( {
 652       size_t image_name_len = strlen(MODULES_IMAGE_NAME);
 653       assert(strncmp(p - image_name_len, MODULES_IMAGE_NAME, image_name_len) == 0,
 654              "first entry must be the modules image");
 655     } );
 656     p += path_sep_len;
 657   } else {
 658     debug_only( {
 659       assert(ClassLoader::string_ends_with(path, MODULES_IMAGE_NAME),
 660              "first entry must be the modules image");
 661     } );
 662   }
 663   return p;
 664 }
 665 
 666 int FileMapInfo::num_paths(const char* path) {
 667   if (path == nullptr) {
 668     return 0;
 669   }
 670   int npaths = 1;
 671   char* p = (char*)path;
 672   while (p != nullptr) {
 673     char* prev = p;
 674     p = strstr((char*)p, os::path_separator());
 675     if (p != nullptr) {
 676       p++;
 677       // don't count empty path
 678       if ((p - prev) > 1) {
 679        npaths++;
 680       }
 681     }
 682   }
 683   return npaths;
 684 }
 685 
 686 // Returns true if a path within the paths exists and has non-zero size.
 687 bool FileMapInfo::check_paths_existence(const char* paths) {
 688   ClasspathStream cp_stream(paths);
 689   bool exist = false;
 690   struct stat st;
 691   while (cp_stream.has_next()) {
 692     const char* path = cp_stream.get_next();
 693     if (os::stat(path, &st) == 0 && st.st_size > 0) {
 694       exist = true;
 695       break;
 696     }
 697   }
 698   return exist;
 699 }
 700 
 701 GrowableArray<const char*>* FileMapInfo::create_dumptime_app_classpath_array() {
 702   assert(CDSConfig::is_dumping_archive(), "sanity");
 703   GrowableArray<const char*>* path_array = new GrowableArray<const char*>(10);
 704   ClassPathEntry* cpe = ClassLoader::app_classpath_entries();
 705   while (cpe != nullptr) {
 706     path_array->append(cpe->name());
 707     cpe = cpe->next();
 708   }
 709   return path_array;
 710 }
 711 
 712 GrowableArray<const char*>* FileMapInfo::create_path_array(const char* paths) {
 713   GrowableArray<const char*>* path_array = new GrowableArray<const char*>(10);
 714   JavaThread* current = JavaThread::current();
 715   ClasspathStream cp_stream(paths);
 716   bool non_jar_in_cp = header()->has_non_jar_in_classpath();
 717   while (cp_stream.has_next()) {
 718     const char* path = cp_stream.get_next();
 719     if (!non_jar_in_cp) {
 720       struct stat st;
 721       if (os::stat(path, &st) == 0) {
 722         path_array->append(path);
 723       }
 724     } else {
 725       const char* canonical_path = ClassLoader::get_canonical_path(path, current);
 726       if (canonical_path != nullptr) {
 727         char* error_msg = nullptr;
 728         jzfile* zip = ClassLoader::open_zip_file(canonical_path, &error_msg, current);
 729         if (zip != nullptr && error_msg == nullptr) {
 730           path_array->append(path);
 731         }
 732       }
 733     }
 734   }
 735   return path_array;
 736 }
 737 
 738 bool FileMapInfo::classpath_failure(const char* msg, const char* name) {
 739   ClassLoader::trace_class_path(msg, name);
 740   if (PrintSharedArchiveAndExit) {
 741     MetaspaceShared::set_archive_loading_failed();
 742   }
 743   return false;
 744 }
 745 
 746 unsigned int FileMapInfo::longest_common_app_classpath_prefix_len(int num_paths,
 747                                                                   GrowableArray<const char*>* rp_array) {
 748   if (num_paths == 0) {
 749     return 0;
 750   }
 751   unsigned int pos;
 752   for (pos = 0; ; pos++) {
 753     for (int i = 0; i < num_paths; i++) {
 754       if (rp_array->at(i)[pos] != '\0' && rp_array->at(i)[pos] == rp_array->at(0)[pos]) {
 755         continue;
 756       }
 757       // search backward for the pos before the file separator char
 758       while (pos > 0) {
 759         if (rp_array->at(0)[--pos] == *os::file_separator()) {
 760           return pos + 1;
 761         }
 762       }
 763       return 0;
 764     }
 765   }
 766   return 0;
 767 }
 768 
 769 bool FileMapInfo::check_paths(int shared_path_start_idx, int num_paths, GrowableArray<const char*>* rp_array,
 770                               unsigned int dumptime_prefix_len, unsigned int runtime_prefix_len) {
 771   int i = 0;
 772   int j = shared_path_start_idx;
 773   while (i < num_paths) {
 774     while (shared_path(j)->from_class_path_attr()) {
 775       // shared_path(j) was expanded from the JAR file attribute "Class-Path:"
 776       // during dump time. It's not included in the -classpath VM argument.
 777       j++;
 778     }
 779     assert(strlen(shared_path(j)->name()) > (size_t)dumptime_prefix_len, "sanity");
 780     const char* dumptime_path = shared_path(j)->name() + dumptime_prefix_len;
 781     assert(strlen(rp_array->at(i)) > (size_t)runtime_prefix_len, "sanity");
 782     const char* runtime_path = rp_array->at(i)  + runtime_prefix_len;
 783     if (!os::same_files(dumptime_path, runtime_path)) {
 784       return false;
 785     }
 786     i++;
 787     j++;
 788   }
 789   return true;
 790 }
 791 
 792 bool FileMapInfo::validate_boot_class_paths() {
 793   //
 794   // - Archive contains boot classes only - relaxed boot path check:
 795   //   Extra path elements appended to the boot path at runtime are allowed.
 796   //
 797   // - Archive contains application or platform classes - strict boot path check:
 798   //   Validate the entire runtime boot path, which must be compatible
 799   //   with the dump time boot path. Appending boot path at runtime is not
 800   //   allowed.
 801   //
 802 
 803   // The first entry in boot path is the modules_image (guaranteed by
 804   // ClassLoader::setup_boot_search_path()). Skip the first entry. The
 805   // path of the runtime modules_image may be different from the dump
 806   // time path (e.g. the JDK image is copied to a different location
 807   // after generating the shared archive), which is acceptable. For most
 808   // common cases, the dump time boot path might contain modules_image only.
 809   char* runtime_boot_path = Arguments::get_boot_class_path();
 810   char* rp = skip_first_path_entry(runtime_boot_path);
 811   assert(shared_path(0)->is_modules_image(), "first shared_path must be the modules image");
 812   int dp_len = header()->app_class_paths_start_index() - 1; // ignore the first path to the module image
 813   bool match = true;
 814 
 815   bool relaxed_check = !header()->has_platform_or_app_classes();
 816   if (dp_len == 0 && rp == nullptr) {
 817     return true;   // ok, both runtime and dump time boot paths have modules_images only
 818   } else if (dp_len == 0 && rp != nullptr) {
 819     if (relaxed_check) {
 820       return true;   // ok, relaxed check, runtime has extra boot append path entries
 821     } else {
 822       ResourceMark rm;
 823       if (check_paths_existence(rp)) {
 824         // If a path exists in the runtime boot paths, it is considered a mismatch
 825         // since there's no boot path specified during dump time.
 826         match = false;
 827       }
 828     }
 829   } else if (dp_len > 0 && rp != nullptr) {
 830     int num;
 831     ResourceMark rm;
 832     GrowableArray<const char*>* rp_array = create_path_array(rp);
 833     int rp_len = rp_array->length();
 834     if (rp_len >= dp_len) {
 835       if (relaxed_check) {
 836         // only check the leading entries in the runtime boot path, up to
 837         // the length of the dump time boot path
 838         num = dp_len;
 839       } else {
 840         // check the full runtime boot path, must match with dump time
 841         num = rp_len;
 842       }
 843       match = check_paths(1, num, rp_array, 0, 0);
 844     } else {
 845       // create_path_array() ignores non-existing paths. Although the dump time and runtime boot classpath lengths
 846       // are the same initially, after the call to create_path_array(), the runtime boot classpath length could become
 847       // shorter. We consider boot classpath mismatch in this case.
 848       match = false;
 849     }
 850   }
 851 
 852   if (!match) {
 853     // The paths are different
 854     return classpath_failure("[BOOT classpath mismatch, actual =", runtime_boot_path);
 855   }
 856   return true;
 857 }
 858 
 859 bool FileMapInfo::validate_app_class_paths(int shared_app_paths_len) {
 860   const char *appcp = Arguments::get_appclasspath();
 861   assert(appcp != nullptr, "null app classpath");
 862   int rp_len = num_paths(appcp);
 863   bool match = false;
 864   if (rp_len < shared_app_paths_len) {
 865     return classpath_failure("Run time APP classpath is shorter than the one at dump time: ", appcp);
 866   }
 867   if (shared_app_paths_len != 0 && rp_len != 0) {
 868     // Prefix is OK: E.g., dump with -cp foo.jar, but run with -cp foo.jar:bar.jar.
 869     ResourceMark rm;
 870     GrowableArray<const char*>* rp_array = create_path_array(appcp);
 871     if (rp_array->length() == 0) {
 872       // None of the jar file specified in the runtime -cp exists.
 873       return classpath_failure("None of the jar file specified in the runtime -cp exists: -Djava.class.path=", appcp);
 874     }
 875     if (rp_array->length() < shared_app_paths_len) {
 876       // create_path_array() ignores non-existing paths. Although the dump time and runtime app classpath lengths
 877       // are the same initially, after the call to create_path_array(), the runtime app classpath length could become
 878       // shorter. We consider app classpath mismatch in this case.
 879       return classpath_failure("[APP classpath mismatch, actual: -Djava.class.path=", appcp);
 880     }
 881 
 882     // Handling of non-existent entries in the classpath: we eliminate all the non-existent
 883     // entries from both the dump time classpath (ClassLoader::update_class_path_entry_list)
 884     // and the runtime classpath (FileMapInfo::create_path_array), and check the remaining
 885     // entries. E.g.:
 886     //
 887     // dump : -cp a.jar:NE1:NE2:b.jar  -> a.jar:b.jar -> recorded in archive.
 888     // run 1: -cp NE3:a.jar:NE4:b.jar  -> a.jar:b.jar -> matched
 889     // run 2: -cp x.jar:NE4:b.jar      -> x.jar:b.jar -> mismatched
 890 
 891     int j = header()->app_class_paths_start_index();
 892     match = check_paths(j, shared_app_paths_len, rp_array, 0, 0);
 893     if (!match) {
 894       // To facilitate app deployment, we allow the JAR files to be moved *together* to
 895       // a different location, as long as they are still stored under the same directory
 896       // structure. E.g., the following is OK.
 897       //     java -Xshare:dump -cp /a/Foo.jar:/a/b/Bar.jar  ...
 898       //     java -Xshare:auto -cp /x/y/Foo.jar:/x/y/b/Bar.jar  ...
 899       unsigned int dumptime_prefix_len = header()->common_app_classpath_prefix_size();
 900       unsigned int runtime_prefix_len = longest_common_app_classpath_prefix_len(shared_app_paths_len, rp_array);
 901       if (dumptime_prefix_len != 0 || runtime_prefix_len != 0) {
 902         log_info(class, path)("LCP length for app classpath (dumptime: %u, runtime: %u)",
 903                               dumptime_prefix_len, runtime_prefix_len);
 904         match = check_paths(j, shared_app_paths_len, rp_array,
 905                                dumptime_prefix_len, runtime_prefix_len);
 906       }
 907       if (!match) {
 908         return classpath_failure("[APP classpath mismatch, actual: -Djava.class.path=", appcp);
 909       }
 910     }
 911   }
 912   return true;
 913 }
 914 
 915 void FileMapInfo::log_paths(const char* msg, int start_idx, int end_idx) {
 916   LogTarget(Info, class, path) lt;
 917   if (lt.is_enabled()) {
 918     LogStream ls(lt);
 919     ls.print("%s", msg);
 920     const char* prefix = "";
 921     for (int i = start_idx; i < end_idx; i++) {
 922       ls.print("%s%s", prefix, shared_path(i)->name());
 923       prefix = os::path_separator();
 924     }
 925     ls.cr();
 926   }
 927 }
 928 
 929 void FileMapInfo::extract_module_paths(const char* runtime_path, GrowableArray<const char*>* module_paths) {
 930   GrowableArray<const char*>* path_array = create_path_array(runtime_path);
 931   int num_paths = path_array->length();
 932   for (int i = 0; i < num_paths; i++) {
 933     const char* name = path_array->at(i);
 934     ClassLoaderExt::extract_jar_files_from_path(name, module_paths);
 935   }
 936   // module paths are stored in sorted order in the CDS archive.
 937   module_paths->sort(ClassLoaderExt::compare_module_path_by_name);
 938 }
 939 
 940 bool FileMapInfo::check_module_paths() {
 941   const char* runtime_path = Arguments::get_property("jdk.module.path");
 942   int archived_num_module_paths = header()->num_module_paths();
 943   if (runtime_path == nullptr && archived_num_module_paths == 0) {
 944     return true;
 945   }
 946   if ((runtime_path == nullptr && archived_num_module_paths > 0) ||
 947       (runtime_path != nullptr && archived_num_module_paths == 0)) {
 948     return false;
 949   }
 950   ResourceMark rm;
 951   GrowableArray<const char*>* module_paths = new GrowableArray<const char*>(3);
 952   extract_module_paths(runtime_path, module_paths);
 953   int num_paths = module_paths->length();
 954   if (num_paths != archived_num_module_paths) {
 955     return false;
 956   }
 957   return check_paths(header()->app_module_paths_start_index(), num_paths, module_paths, 0, 0);
 958 }
 959 
 960 bool FileMapInfo::validate_shared_path_table() {
 961   assert(CDSConfig::is_using_archive(), "runtime only");
 962 
 963   _validating_shared_path_table = true;
 964 
 965   // Load the shared path table info from the archive header
 966   _shared_path_table = header()->shared_path_table();
 967 
 968   bool matched_module_paths = true;
 969   if (CDSConfig::is_dumping_dynamic_archive() || header()->has_full_module_graph()) {
 970     matched_module_paths = check_module_paths();
 971   }
 972   if (header()->has_full_module_graph() && !matched_module_paths) {
 973     CDSConfig::stop_using_optimized_module_handling();
 974     log_info(cds)("optimized module handling: disabled because of mismatched module paths");
 975   }
 976 
 977   if (CDSConfig::is_dumping_dynamic_archive()) {
 978     // Only support dynamic dumping with the usage of the default CDS archive
 979     // or a simple base archive.
 980     // If the base layer archive contains additional path component besides
 981     // the runtime image and the -cp, dynamic dumping is disabled.
 982     //
 983     // When dynamic archiving is enabled, the _shared_path_table is overwritten
 984     // to include the application path and stored in the top layer archive.
 985     assert(shared_path(0)->is_modules_image(), "first shared_path must be the modules image");
 986     if (header()->app_class_paths_start_index() > 1) {
 987       CDSConfig::disable_dumping_dynamic_archive();
 988       log_warning(cds)(
 989         "Dynamic archiving is disabled because base layer archive has appended boot classpath");
 990     }
 991     if (header()->num_module_paths() > 0) {
 992       if (!matched_module_paths) {
 993         CDSConfig::disable_dumping_dynamic_archive();
 994         log_warning(cds)(
 995           "Dynamic archiving is disabled because base layer archive has a different module path");
 996       }
 997     }
 998   }
 999 
1000   log_paths("Expecting BOOT path=", 0, header()->app_class_paths_start_index());
1001   log_paths("Expecting -Djava.class.path=", header()->app_class_paths_start_index(), header()->app_module_paths_start_index());
1002 
1003   int module_paths_start_index = header()->app_module_paths_start_index();
1004   int shared_app_paths_len = 0;
1005 
1006   // validate the path entries up to the _max_used_path_index
1007   for (int i=0; i < header()->max_used_path_index() + 1; i++) {
1008     if (i < module_paths_start_index) {
1009       if (shared_path(i)->validate()) {
1010         // Only count the app class paths not from the "Class-path" attribute of a jar manifest.
1011         if (!shared_path(i)->from_class_path_attr() && i >= header()->app_class_paths_start_index()) {
1012           shared_app_paths_len++;
1013         }
1014         log_info(class, path)("ok");
1015       } else {
1016         if (_dynamic_archive_info != nullptr && _dynamic_archive_info->_is_static) {
1017           assert(!CDSConfig::is_using_archive(), "UseSharedSpaces should be disabled");
1018         }
1019         return false;
1020       }
1021     } else if (i >= module_paths_start_index) {
1022       if (shared_path(i)->validate(false /* not a class path entry */)) {
1023         log_info(class, path)("ok");
1024       } else {
1025         if (_dynamic_archive_info != nullptr && _dynamic_archive_info->_is_static) {
1026           assert(!CDSConfig::is_using_archive(), "UseSharedSpaces should be disabled");
1027         }
1028         return false;
1029       }
1030     }
1031   }
1032 
1033   if (header()->max_used_path_index() == 0) {
1034     // default archive only contains the module image in the bootclasspath
1035     assert(shared_path(0)->is_modules_image(), "first shared_path must be the modules image");
1036   } else {
1037     if (!validate_boot_class_paths() || !validate_app_class_paths(shared_app_paths_len)) {
1038       const char* mismatch_msg = "shared class paths mismatch";
1039       const char* hint_msg = log_is_enabled(Info, class, path) ?
1040           "" : " (hint: enable -Xlog:class+path=info to diagnose the failure)";
1041       if (RequireSharedSpaces) {
1042         log_error(cds)("%s%s", mismatch_msg, hint_msg);
1043         MetaspaceShared::unrecoverable_loading_error();
1044       } else {
1045         log_warning(cds)("%s%s", mismatch_msg, hint_msg);
1046       }
1047       return false;
1048     }
1049   }
1050 
1051   validate_non_existent_class_paths();


1052 
1053   _validating_shared_path_table = false;
1054 
1055 #if INCLUDE_JVMTI
1056   if (_classpath_entries_for_jvmti != nullptr) {
1057     os::free(_classpath_entries_for_jvmti);
1058   }
1059   size_t sz = sizeof(ClassPathEntry*) * get_number_of_shared_paths();
1060   _classpath_entries_for_jvmti = (ClassPathEntry**)os::malloc(sz, mtClass);
1061   memset((void*)_classpath_entries_for_jvmti, 0, sz);
1062 #endif
1063 
1064   return true;
1065 }
1066 
1067 void FileMapInfo::validate_non_existent_class_paths() {
1068   // All of the recorded non-existent paths came from the Class-Path: attribute from the JAR
1069   // files on the app classpath. If any of these are found to exist during runtime,
1070   // it will change how classes are loading for the app loader. For safety, disable
1071   // loading of archived platform/app classes (currently there's no way to disable just the
1072   // app classes).
1073 
1074   assert(CDSConfig::is_using_archive(), "runtime only");
1075   for (int i = header()->app_module_paths_start_index() + header()->num_module_paths();
1076        i < get_number_of_shared_paths();
1077        i++) {
1078     SharedClassPathEntry* ent = shared_path(i);
1079     if (!ent->check_non_existent()) {
1080       log_warning(cds)("Archived non-system classes are disabled because the "
1081               "file %s exists", ent->name());
1082       header()->set_has_platform_or_app_classes(false);






1083     }
1084   }


1085 }
1086 
1087 // A utility class for reading/validating the GenericCDSFileMapHeader portion of
1088 // a CDS archive's header. The file header of all CDS archives with versions from
1089 // CDS_GENERIC_HEADER_SUPPORTED_MIN_VERSION (12) are guaranteed to always start
1090 // with GenericCDSFileMapHeader. This makes it possible to read important information
1091 // from a CDS archive created by a different version of HotSpot, so that we can
1092 // automatically regenerate the archive as necessary (JDK-8261455).
1093 class FileHeaderHelper {
1094   int _fd;
1095   bool _is_valid;
1096   bool _is_static;
1097   GenericCDSFileMapHeader* _header;
1098   const char* _archive_name;
1099   const char* _base_archive_name;
1100 
1101 public:
1102   FileHeaderHelper(const char* archive_name, bool is_static) {
1103     _fd = -1;
1104     _is_valid = false;
1105     _header = nullptr;
1106     _base_archive_name = nullptr;
1107     _archive_name = archive_name;
1108     _is_static = is_static;
1109   }
1110 
1111   ~FileHeaderHelper() {
1112     if (_header != nullptr) {
1113       FREE_C_HEAP_ARRAY(char, _header);
1114     }
1115     if (_fd != -1) {
1116       ::close(_fd);
1117     }
1118   }
1119 
1120   bool initialize() {
1121     assert(_archive_name != nullptr, "Archive name is null");
1122     _fd = os::open(_archive_name, O_RDONLY | O_BINARY, 0);
1123     if (_fd < 0) {
1124       log_info(cds)("Specified shared archive not found (%s)", _archive_name);
1125       return false;
1126     }
1127     return initialize(_fd);
1128   }
1129 
1130   // for an already opened file, do not set _fd
1131   bool initialize(int fd) {
1132     assert(_archive_name != nullptr, "Archive name is null");
1133     assert(fd != -1, "Archive must be opened already");
1134     // First read the generic header so we know the exact size of the actual header.
1135     GenericCDSFileMapHeader gen_header;
1136     size_t size = sizeof(GenericCDSFileMapHeader);
1137     os::lseek(fd, 0, SEEK_SET);
1138     size_t n = ::read(fd, (void*)&gen_header, (unsigned int)size);
1139     if (n != size) {
1140       log_warning(cds)("Unable to read generic CDS file map header from shared archive");
1141       return false;
1142     }
1143 
1144     if (gen_header._magic != CDS_ARCHIVE_MAGIC &&
1145         gen_header._magic != CDS_DYNAMIC_ARCHIVE_MAGIC) {
1146       log_warning(cds)("The shared archive file has a bad magic number: %#x", gen_header._magic);
1147       return false;
1148     }
1149 
1150     if (gen_header._version < CDS_GENERIC_HEADER_SUPPORTED_MIN_VERSION) {
1151       log_warning(cds)("Cannot handle shared archive file version 0x%x. Must be at least 0x%x.",
1152                                  gen_header._version, CDS_GENERIC_HEADER_SUPPORTED_MIN_VERSION);
1153       return false;
1154     }
1155 
1156     if (gen_header._version !=  CURRENT_CDS_ARCHIVE_VERSION) {
1157       log_warning(cds)("The shared archive file version 0x%x does not match the required version 0x%x.",
1158                                  gen_header._version, CURRENT_CDS_ARCHIVE_VERSION);
1159     }
1160 
1161     size_t filelen = os::lseek(fd, 0, SEEK_END);
1162     if (gen_header._header_size >= filelen) {
1163       log_warning(cds)("Archive file header larger than archive file");
1164       return false;
1165     }
1166 
1167     // Read the actual header and perform more checks
1168     size = gen_header._header_size;
1169     _header = (GenericCDSFileMapHeader*)NEW_C_HEAP_ARRAY(char, size, mtInternal);
1170     os::lseek(fd, 0, SEEK_SET);
1171     n = ::read(fd, (void*)_header, (unsigned int)size);
1172     if (n != size) {
1173       log_warning(cds)("Unable to read actual CDS file map header from shared archive");
1174       return false;
1175     }
1176 
1177     if (!check_header_crc()) {
1178       return false;
1179     }
1180 
1181     if (!check_and_init_base_archive_name()) {
1182       return false;
1183     }
1184 
1185     // All fields in the GenericCDSFileMapHeader has been validated.
1186     _is_valid = true;
1187     return true;
1188   }
1189 
1190   GenericCDSFileMapHeader* get_generic_file_header() {
1191     assert(_header != nullptr && _is_valid, "must be a valid archive file");
1192     return _header;
1193   }
1194 
1195   const char* base_archive_name() {
1196     assert(_header != nullptr && _is_valid, "must be a valid archive file");
1197     return _base_archive_name;
1198   }
1199 
1200  private:
1201   bool check_header_crc() const {
1202     if (VerifySharedSpaces) {
1203       FileMapHeader* header = (FileMapHeader*)_header;
1204       int actual_crc = header->compute_crc();
1205       if (actual_crc != header->crc()) {
1206         log_info(cds)("_crc expected: %d", header->crc());
1207         log_info(cds)("       actual: %d", actual_crc);
1208         log_warning(cds)("Header checksum verification failed.");
1209         return false;
1210       }
1211     }
1212     return true;
1213   }
1214 
1215   bool check_and_init_base_archive_name() {
1216     unsigned int name_offset = _header->_base_archive_name_offset;
1217     unsigned int name_size   = _header->_base_archive_name_size;
1218     unsigned int header_size = _header->_header_size;
1219 
1220     if (name_offset + name_size < name_offset) {
1221       log_warning(cds)("base_archive_name offset/size overflow: " UINT32_FORMAT "/" UINT32_FORMAT,
1222                                  name_offset, name_size);
1223       return false;
1224     }
1225     if (_header->_magic == CDS_ARCHIVE_MAGIC) {
1226       if (name_offset != 0) {
1227         log_warning(cds)("static shared archive must have zero _base_archive_name_offset");
1228         return false;
1229       }
1230       if (name_size != 0) {
1231         log_warning(cds)("static shared archive must have zero _base_archive_name_size");
1232         return false;
1233       }
1234     } else {
1235       assert(_header->_magic == CDS_DYNAMIC_ARCHIVE_MAGIC, "must be");
1236       if ((name_size == 0 && name_offset != 0) ||
1237           (name_size != 0 && name_offset == 0)) {
1238         // If either is zero, both must be zero. This indicates that we are using the default base archive.
1239         log_warning(cds)("Invalid base_archive_name offset/size: " UINT32_FORMAT "/" UINT32_FORMAT,
1240                                    name_offset, name_size);
1241         return false;
1242       }
1243       if (name_size > 0) {
1244         if (name_offset + name_size > header_size) {
1245           log_warning(cds)("Invalid base_archive_name offset/size (out of range): "
1246                                      UINT32_FORMAT " + " UINT32_FORMAT " > " UINT32_FORMAT ,
1247                                      name_offset, name_size, header_size);
1248           return false;
1249         }
1250         const char* name = ((const char*)_header) + _header->_base_archive_name_offset;
1251         if (name[name_size - 1] != '\0' || strlen(name) != name_size - 1) {
1252           log_warning(cds)("Base archive name is damaged");
1253           return false;
1254         }
1255         if (!os::file_exists(name)) {
1256           log_warning(cds)("Base archive %s does not exist", name);
1257           return false;
1258         }
1259         _base_archive_name = name;
1260       }
1261     }
1262 
1263     return true;
1264   }
1265 };
1266 
1267 // Return value:
1268 // false:
1269 //      <archive_name> is not a valid archive. *base_archive_name is set to null.
1270 // true && (*base_archive_name) == nullptr:
1271 //      <archive_name> is a valid static archive.
1272 // true && (*base_archive_name) != nullptr:
1273 //      <archive_name> is a valid dynamic archive.
1274 bool FileMapInfo::get_base_archive_name_from_header(const char* archive_name,
1275                                                     char** base_archive_name) {
1276   FileHeaderHelper file_helper(archive_name, false);
1277   *base_archive_name = nullptr;
1278 
1279   if (!file_helper.initialize()) {
1280     return false;
1281   }
1282   GenericCDSFileMapHeader* header = file_helper.get_generic_file_header();
1283   if (header->_magic != CDS_DYNAMIC_ARCHIVE_MAGIC) {
1284     assert(header->_magic == CDS_ARCHIVE_MAGIC, "must be");
1285     if (AutoCreateSharedArchive) {
1286      log_warning(cds)("AutoCreateSharedArchive is ignored because %s is a static archive", archive_name);
1287     }
1288     return true;
1289   }
1290 
1291   const char* base = file_helper.base_archive_name();
1292   if (base == nullptr) {
1293     *base_archive_name = CDSConfig::default_archive_path();
1294   } else {
1295     *base_archive_name = os::strdup_check_oom(base);
1296   }
1297 
1298   return true;
1299 }
1300 
1301 // Read the FileMapInfo information from the file.
1302 
1303 bool FileMapInfo::init_from_file(int fd) {
1304   FileHeaderHelper file_helper(_full_path, _is_static);
1305   if (!file_helper.initialize(fd)) {
1306     log_warning(cds)("Unable to read the file header.");
1307     return false;
1308   }
1309   GenericCDSFileMapHeader* gen_header = file_helper.get_generic_file_header();
1310 
1311   if (_is_static) {
1312     if (gen_header->_magic != CDS_ARCHIVE_MAGIC) {
1313       log_warning(cds)("Not a base shared archive: %s", _full_path);
1314       return false;
1315     }
1316   } else {
1317     if (gen_header->_magic != CDS_DYNAMIC_ARCHIVE_MAGIC) {
1318       log_warning(cds)("Not a top shared archive: %s", _full_path);
1319       return false;
1320     }
1321   }
1322 
1323   _header = (FileMapHeader*)os::malloc(gen_header->_header_size, mtInternal);
1324   os::lseek(fd, 0, SEEK_SET); // reset to begin of the archive
1325   size_t size = gen_header->_header_size;
1326   size_t n = ::read(fd, (void*)_header, (unsigned int)size);
1327   if (n != size) {
1328     log_warning(cds)("Failed to read file header from the top archive file\n");
1329     return false;
1330   }
1331 
1332   if (header()->version() != CURRENT_CDS_ARCHIVE_VERSION) {
1333     log_info(cds)("_version expected: 0x%x", CURRENT_CDS_ARCHIVE_VERSION);
1334     log_info(cds)("           actual: 0x%x", header()->version());
1335     log_warning(cds)("The shared archive file has the wrong version.");
1336     return false;
1337   }
1338 
1339   int common_path_size = header()->common_app_classpath_prefix_size();
1340   if (common_path_size < 0) {
1341       log_warning(cds)("common app classpath prefix len < 0");
1342       return false;
1343   }
1344 
1345   unsigned int base_offset = header()->base_archive_name_offset();
1346   unsigned int name_size = header()->base_archive_name_size();
1347   unsigned int header_size = header()->header_size();
1348   if (base_offset != 0 && name_size != 0) {
1349     if (header_size != base_offset + name_size) {
1350       log_info(cds)("_header_size: " UINT32_FORMAT, header_size);
1351       log_info(cds)("common_app_classpath_size: " UINT32_FORMAT, header()->common_app_classpath_prefix_size());
1352       log_info(cds)("base_archive_name_size: " UINT32_FORMAT, header()->base_archive_name_size());
1353       log_info(cds)("base_archive_name_offset: " UINT32_FORMAT, header()->base_archive_name_offset());
1354       log_warning(cds)("The shared archive file has an incorrect header size.");
1355       return false;
1356     }
1357   }
1358 
1359   const char* actual_ident = header()->jvm_ident();
1360 
1361   if (actual_ident[JVM_IDENT_MAX-1] != 0) {
1362     log_warning(cds)("JVM version identifier is corrupted.");
1363     return false;
1364   }
1365 
1366   char expected_ident[JVM_IDENT_MAX];
1367   get_header_version(expected_ident);
1368   if (strncmp(actual_ident, expected_ident, JVM_IDENT_MAX-1) != 0) {
1369     log_info(cds)("_jvm_ident expected: %s", expected_ident);
1370     log_info(cds)("             actual: %s", actual_ident);
1371     log_warning(cds)("The shared archive file was created by a different"
1372                   " version or build of HotSpot");
1373     return false;
1374   }
1375 
1376   _file_offset = header()->header_size(); // accounts for the size of _base_archive_name
1377 
1378   size_t len = os::lseek(fd, 0, SEEK_END);
1379 
1380   for (int i = 0; i < MetaspaceShared::n_regions; i++) {
1381     FileMapRegion* r = region_at(i);
1382     if (r->file_offset() > len || len - r->file_offset() < r->used()) {
1383       log_warning(cds)("The shared archive file has been truncated.");
1384       return false;
1385     }
1386   }
1387 
1388   return true;
1389 }
1390 
1391 void FileMapInfo::seek_to_position(size_t pos) {
1392   if (os::lseek(_fd, (long)pos, SEEK_SET) < 0) {
1393     log_error(cds)("Unable to seek to position " SIZE_FORMAT, pos);
1394     MetaspaceShared::unrecoverable_loading_error();
1395   }
1396 }
1397 
1398 // Read the FileMapInfo information from the file.
1399 bool FileMapInfo::open_for_read() {
1400   if (_file_open) {
1401     return true;
1402   }
1403   log_info(cds)("trying to map %s", _full_path);
1404   int fd = os::open(_full_path, O_RDONLY | O_BINARY, 0);
1405   if (fd < 0) {
1406     if (errno == ENOENT) {
1407       log_info(cds)("Specified shared archive not found (%s)", _full_path);
1408     } else {
1409       log_warning(cds)("Failed to open shared archive file (%s)",
1410                     os::strerror(errno));
1411     }
1412     return false;
1413   } else {
1414     log_info(cds)("Opened archive %s.", _full_path);
1415   }
1416 
1417   _fd = fd;
1418   _file_open = true;
1419   return true;
1420 }
1421 
1422 // Write the FileMapInfo information to the file.
1423 
1424 void FileMapInfo::open_for_write() {
1425   LogMessage(cds) msg;
1426   if (msg.is_info()) {
1427     msg.info("Dumping shared data to file: ");
1428     msg.info("   %s", _full_path);
1429   }
1430 
1431 #ifdef _WINDOWS  // On Windows, need WRITE permission to remove the file.
1432     chmod(_full_path, _S_IREAD | _S_IWRITE);
1433 #endif
1434 
1435   // Use remove() to delete the existing file because, on Unix, this will
1436   // allow processes that have it open continued access to the file.
1437   remove(_full_path);
1438   int fd = os::open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444);
1439   if (fd < 0) {
1440     log_error(cds)("Unable to create shared archive file %s: (%s).", _full_path,
1441                    os::strerror(errno));
1442     MetaspaceShared::writing_error();
1443     return;
1444   }
1445   _fd = fd;
1446   _file_open = true;
1447 
1448   // Seek past the header. We will write the header after all regions are written
1449   // and their CRCs computed.
1450   size_t header_bytes = header()->header_size();
1451 
1452   header_bytes = align_up(header_bytes, MetaspaceShared::core_region_alignment());
1453   _file_offset = header_bytes;
1454   seek_to_position(_file_offset);
1455 }
1456 
1457 // Write the header to the file, seek to the next allocation boundary.
1458 
1459 void FileMapInfo::write_header() {
1460   _file_offset = 0;
1461   seek_to_position(_file_offset);
1462   assert(is_file_position_aligned(), "must be");
1463   write_bytes(header(), header()->header_size());
1464 }
1465 
1466 size_t FileMapRegion::used_aligned() const {
1467   return align_up(used(), MetaspaceShared::core_region_alignment());
1468 }
1469 
1470 void FileMapRegion::init(int region_index, size_t mapping_offset, size_t size, bool read_only,
1471                          bool allow_exec, int crc) {
1472   _is_heap_region = HeapShared::is_heap_region(region_index);
1473   _is_bitmap_region = (region_index == MetaspaceShared::bm);
1474   _mapping_offset = mapping_offset;
1475   _used = size;
1476   _read_only = read_only;
1477   _allow_exec = allow_exec;
1478   _crc = crc;
1479   _mapped_from_file = false;
1480   _mapped_base = nullptr;
1481 }
1482 
1483 void FileMapRegion::init_oopmap(size_t offset, size_t size_in_bits) {
1484   _oopmap_offset = offset;
1485   _oopmap_size_in_bits = size_in_bits;
1486 }
1487 
1488 void FileMapRegion::init_ptrmap(size_t offset, size_t size_in_bits) {
1489   _ptrmap_offset = offset;
1490   _ptrmap_size_in_bits = size_in_bits;
1491 }
1492 
1493 bool FileMapRegion::check_region_crc(char* base) const {
1494   // This function should be called after the region has been properly
1495   // loaded into memory via FileMapInfo::map_region() or FileMapInfo::read_region().
1496   // I.e., this->mapped_base() must be valid.
1497   size_t sz = used();
1498   if (sz == 0) {
1499     return true;
1500   }
1501 
1502   assert(base != nullptr, "must be initialized");
1503   int crc = ClassLoader::crc32(0, base, (jint)sz);
1504   if (crc != this->crc()) {
1505     log_warning(cds)("Checksum verification failed.");
1506     return false;
1507   }
1508   return true;
1509 }
1510 
1511 static const char* region_name(int region_index) {
1512   static const char* names[] = {
1513     "rw", "ro", "bm", "hp"
1514   };
1515   const int num_regions = sizeof(names)/sizeof(names[0]);
1516   assert(0 <= region_index && region_index < num_regions, "sanity");
1517 
1518   return names[region_index];
1519 }
1520 
1521 BitMapView FileMapInfo::bitmap_view(int region_index, bool is_oopmap) {
1522   FileMapRegion* r = region_at(region_index);
1523   char* bitmap_base = is_static() ? FileMapInfo::current_info()->map_bitmap_region() : FileMapInfo::dynamic_info()->map_bitmap_region();
1524   bitmap_base += is_oopmap ? r->oopmap_offset() : r->ptrmap_offset();
1525   size_t size_in_bits = is_oopmap ? r->oopmap_size_in_bits() : r->ptrmap_size_in_bits();
1526 
1527   log_debug(cds, reloc)("mapped %s relocation %smap @ " INTPTR_FORMAT " (" SIZE_FORMAT " bits)",
1528                         region_name(region_index), is_oopmap ? "oop" : "ptr",
1529                         p2i(bitmap_base), size_in_bits);
1530 
1531   return BitMapView((BitMap::bm_word_t*)(bitmap_base), size_in_bits);
1532 }
1533 
1534 BitMapView FileMapInfo::oopmap_view(int region_index) {
1535     return bitmap_view(region_index, /*is_oopmap*/true);
1536   }
1537 
1538 BitMapView FileMapInfo::ptrmap_view(int region_index) {
1539   return bitmap_view(region_index, /*is_oopmap*/false);
1540 }
1541 
1542 void FileMapRegion::print(outputStream* st, int region_index) {
1543   st->print_cr("============ region ============= %d \"%s\"", region_index, region_name(region_index));
1544   st->print_cr("- crc:                            0x%08x", _crc);
1545   st->print_cr("- read_only:                      %d", _read_only);
1546   st->print_cr("- allow_exec:                     %d", _allow_exec);
1547   st->print_cr("- is_heap_region:                 %d", _is_heap_region);
1548   st->print_cr("- is_bitmap_region:               %d", _is_bitmap_region);
1549   st->print_cr("- mapped_from_file:               %d", _mapped_from_file);
1550   st->print_cr("- file_offset:                    " SIZE_FORMAT_X, _file_offset);
1551   st->print_cr("- mapping_offset:                 " SIZE_FORMAT_X, _mapping_offset);
1552   st->print_cr("- used:                           " SIZE_FORMAT, _used);
1553   st->print_cr("- oopmap_offset:                  " SIZE_FORMAT_X, _oopmap_offset);
1554   st->print_cr("- oopmap_size_in_bits:            " SIZE_FORMAT, _oopmap_size_in_bits);
1555   st->print_cr("- ptrmap_offset:                  " SIZE_FORMAT_X, _ptrmap_offset);
1556   st->print_cr("- ptrmap_size_in_bits:            " SIZE_FORMAT, _ptrmap_size_in_bits);
1557   st->print_cr("- mapped_base:                    " INTPTR_FORMAT, p2i(_mapped_base));
1558 }
1559 
1560 void FileMapInfo::write_region(int region, char* base, size_t size,
1561                                bool read_only, bool allow_exec) {
1562   assert(CDSConfig::is_dumping_archive(), "sanity");
1563 
1564   FileMapRegion* r = region_at(region);
1565   char* requested_base;
1566   size_t mapping_offset = 0;
1567 
1568   if (region == MetaspaceShared::bm) {
1569     requested_base = nullptr; // always null for bm region
1570   } else if (size == 0) {
1571     // This is an unused region (e.g., a heap region when !INCLUDE_CDS_JAVA_HEAP)
1572     requested_base = nullptr;
1573   } else if (HeapShared::is_heap_region(region)) {
1574     assert(HeapShared::can_write(), "sanity");
1575 #if INCLUDE_CDS_JAVA_HEAP
1576     assert(!CDSConfig::is_dumping_dynamic_archive(), "must be");
1577     requested_base = (char*)ArchiveHeapWriter::requested_address();
1578     if (UseCompressedOops) {
1579       mapping_offset = (size_t)((address)requested_base - CompressedOops::base());
1580       assert((mapping_offset >> CompressedOops::shift()) << CompressedOops::shift() == mapping_offset, "must be");
1581     } else {
1582       mapping_offset = 0; // not used with !UseCompressedOops
1583     }
1584 #endif // INCLUDE_CDS_JAVA_HEAP
1585   } else {
1586     char* requested_SharedBaseAddress = (char*)MetaspaceShared::requested_base_address();
1587     requested_base = ArchiveBuilder::current()->to_requested(base);
1588     assert(requested_base >= requested_SharedBaseAddress, "must be");
1589     mapping_offset = requested_base - requested_SharedBaseAddress;
1590   }
1591 
1592   r->set_file_offset(_file_offset);
1593   int crc = ClassLoader::crc32(0, base, (jint)size);
1594   if (size > 0) {
1595     log_info(cds)("Shared file region (%s) %d: " SIZE_FORMAT_W(8)
1596                    " bytes, addr " INTPTR_FORMAT " file offset 0x%08" PRIxPTR
1597                    " crc 0x%08x",
1598                    region_name(region), region, size, p2i(requested_base), _file_offset, crc);



1599   }
1600 
1601   r->init(region, mapping_offset, size, read_only, allow_exec, crc);
1602 
1603   if (base != nullptr) {
1604     write_bytes_aligned(base, size);
1605   }
1606 }
1607 
1608 static size_t write_bitmap(const CHeapBitMap* map, char* output, size_t offset) {
1609   size_t size_in_bytes = map->size_in_bytes();
1610   map->write_to((BitMap::bm_word_t*)(output + offset), size_in_bytes);
1611   return offset + size_in_bytes;
1612 }
1613 
1614 // The sorting code groups the objects with non-null oop/ptrs together.
1615 // Relevant bitmaps then have lots of leading and trailing zeros, which
1616 // we do not have to store.
1617 size_t FileMapInfo::remove_bitmap_zeros(CHeapBitMap* map) {
1618   BitMap::idx_t first_set = map->find_first_set_bit(0);
1619   BitMap::idx_t last_set  = map->find_last_set_bit(0);
1620   size_t old_size = map->size();
1621 
1622   // Slice and resize bitmap
1623   map->truncate(first_set, last_set + 1);
1624 
1625   assert(map->at(0), "First bit should be set");
1626   assert(map->at(map->size() - 1), "Last bit should be set");
1627   assert(map->size() <= old_size, "sanity");
1628 
1629   return first_set;
1630 }
1631 
1632 char* FileMapInfo::write_bitmap_region(CHeapBitMap* rw_ptrmap, CHeapBitMap* ro_ptrmap, ArchiveHeapInfo* heap_info,


1633                                        size_t &size_in_bytes) {
1634   size_t removed_rw_leading_zeros = remove_bitmap_zeros(rw_ptrmap);
1635   size_t removed_ro_leading_zeros = remove_bitmap_zeros(ro_ptrmap);
1636   header()->set_rw_ptrmap_start_pos(removed_rw_leading_zeros);
1637   header()->set_ro_ptrmap_start_pos(removed_ro_leading_zeros);
1638   size_in_bytes = rw_ptrmap->size_in_bytes() + ro_ptrmap->size_in_bytes();
1639 
1640   if (heap_info->is_used()) {
1641     // Remove leading and trailing zeros
1642     size_t removed_oop_leading_zeros = remove_bitmap_zeros(heap_info->oopmap());
1643     size_t removed_ptr_leading_zeros = remove_bitmap_zeros(heap_info->ptrmap());
1644     header()->set_heap_oopmap_start_pos(removed_oop_leading_zeros);
1645     header()->set_heap_ptrmap_start_pos(removed_ptr_leading_zeros);
1646 
1647     size_in_bytes += heap_info->oopmap()->size_in_bytes();
1648     size_in_bytes += heap_info->ptrmap()->size_in_bytes();
1649   }
1650 
1651   // The bitmap region contains up to 4 parts:
1652   // rw_ptrmap:           metaspace pointers inside the read-write region
1653   // ro_ptrmap:           metaspace pointers inside the read-only region
1654   // heap_info->oopmap(): Java oop pointers in the heap region
1655   // heap_info->ptrmap(): metaspace pointers in the heap region
1656   char* buffer = NEW_C_HEAP_ARRAY(char, size_in_bytes, mtClassShared);
1657   size_t written = 0;
1658 
1659   region_at(MetaspaceShared::rw)->init_ptrmap(0, rw_ptrmap->size());
1660   written = write_bitmap(rw_ptrmap, buffer, written);
1661 
1662   region_at(MetaspaceShared::ro)->init_ptrmap(written, ro_ptrmap->size());
1663   written = write_bitmap(ro_ptrmap, buffer, written);
1664 



1665   if (heap_info->is_used()) {
1666     FileMapRegion* r = region_at(MetaspaceShared::hp);
1667 
1668     r->init_oopmap(written, heap_info->oopmap()->size());
1669     written = write_bitmap(heap_info->oopmap(), buffer, written);
1670 
1671     r->init_ptrmap(written, heap_info->ptrmap()->size());
1672     written = write_bitmap(heap_info->ptrmap(), buffer, written);
1673   }
1674 
1675   write_region(MetaspaceShared::bm, (char*)buffer, size_in_bytes, /*read_only=*/true, /*allow_exec=*/false);
1676   return buffer;
1677 }
1678 
1679 size_t FileMapInfo::write_heap_region(ArchiveHeapInfo* heap_info) {
1680   char* buffer_start = heap_info->buffer_start();
1681   size_t buffer_size = heap_info->buffer_byte_size();
1682   write_region(MetaspaceShared::hp, buffer_start, buffer_size, false, false);
1683   header()->set_heap_root_segments(heap_info->heap_root_segments());
1684   return buffer_size;
1685 }
1686 
1687 // Dump bytes to file -- at the current file position.
1688 
1689 void FileMapInfo::write_bytes(const void* buffer, size_t nbytes) {
1690   assert(_file_open, "must be");
1691   if (!os::write(_fd, buffer, nbytes)) {
1692     // If the shared archive is corrupted, close it and remove it.
1693     close();
1694     remove(_full_path);
1695     MetaspaceShared::writing_error("Unable to write to shared archive file.");
1696   }
1697   _file_offset += nbytes;
1698 }
1699 
1700 bool FileMapInfo::is_file_position_aligned() const {
1701   return _file_offset == align_up(_file_offset,
1702                                   MetaspaceShared::core_region_alignment());
1703 }
1704 
1705 // Align file position to an allocation unit boundary.
1706 
1707 void FileMapInfo::align_file_position() {
1708   assert(_file_open, "must be");
1709   size_t new_file_offset = align_up(_file_offset,
1710                                     MetaspaceShared::core_region_alignment());
1711   if (new_file_offset != _file_offset) {
1712     _file_offset = new_file_offset;
1713     // Seek one byte back from the target and write a byte to insure
1714     // that the written file is the correct length.
1715     _file_offset -= 1;
1716     seek_to_position(_file_offset);
1717     char zero = 0;
1718     write_bytes(&zero, 1);
1719   }
1720 }
1721 
1722 
1723 // Dump bytes to file -- at the current file position.
1724 
1725 void FileMapInfo::write_bytes_aligned(const void* buffer, size_t nbytes) {
1726   align_file_position();
1727   write_bytes(buffer, nbytes);
1728   align_file_position();
1729 }
1730 
1731 // Close the shared archive file.  This does NOT unmap mapped regions.
1732 
1733 void FileMapInfo::close() {
1734   if (_file_open) {
1735     if (::close(_fd) < 0) {
1736       MetaspaceShared::unrecoverable_loading_error("Unable to close the shared archive file.");
1737     }
1738     _file_open = false;
1739     _fd = -1;
1740   }
1741 }
1742 
1743 /*
1744  * Same as os::map_memory() but also pretouches if AlwaysPreTouch is enabled.
1745  */
1746 static char* map_memory(int fd, const char* file_name, size_t file_offset,
1747                         char *addr, size_t bytes, bool read_only,
1748                         bool allow_exec, MemTag mem_tag = mtNone) {
1749   char* mem = os::map_memory(fd, file_name, file_offset, addr, bytes,
1750                              AlwaysPreTouch ? false : read_only,
1751                              allow_exec, mem_tag);
1752   if (mem != nullptr && AlwaysPreTouch) {
1753     os::pretouch_memory(mem, mem + bytes);
1754   }
1755   return mem;
1756 }
1757 
1758 // JVM/TI RedefineClasses() support:
1759 // Remap the shared readonly space to shared readwrite, private.
1760 bool FileMapInfo::remap_shared_readonly_as_readwrite() {
1761   int idx = MetaspaceShared::ro;
1762   FileMapRegion* r = region_at(idx);
1763   if (!r->read_only()) {
1764     // the space is already readwrite so we are done
1765     return true;
1766   }
1767   size_t size = r->used_aligned();
1768   if (!open_for_read()) {
1769     return false;
1770   }
1771   char *addr = r->mapped_base();
1772   // This path should not be reached for Windows; see JDK-8222379.
1773   assert(WINDOWS_ONLY(false) NOT_WINDOWS(true), "Don't call on Windows");
1774   // Replace old mapping with new one that is writable.
1775   char *base = os::map_memory(_fd, _full_path, r->file_offset(),
1776                               addr, size, false /* !read_only */,
1777                               r->allow_exec());
1778   close();
1779   // These have to be errors because the shared region is now unmapped.
1780   if (base == nullptr) {
1781     log_error(cds)("Unable to remap shared readonly space (errno=%d).", errno);
1782     vm_exit(1);
1783   }
1784   if (base != addr) {
1785     log_error(cds)("Unable to remap shared readonly space (errno=%d).", errno);
1786     vm_exit(1);
1787   }
1788   r->set_read_only(false);
1789   return true;
1790 }
1791 
1792 // Memory map a region in the address space.
1793 static const char* shared_region_name[] = { "ReadWrite", "ReadOnly", "Bitmap", "Heap" };
1794 
1795 MapArchiveResult FileMapInfo::map_regions(int regions[], int num_regions, char* mapped_base_address, ReservedSpace rs) {
1796   DEBUG_ONLY(FileMapRegion* last_region = nullptr);
1797   intx addr_delta = mapped_base_address - header()->requested_base_address();
1798 
1799   // Make sure we don't attempt to use header()->mapped_base_address() unless
1800   // it's been successfully mapped.
1801   DEBUG_ONLY(header()->set_mapped_base_address((char*)(uintptr_t)0xdeadbeef);)
1802 
1803   for (int i = 0; i < num_regions; i++) {
1804     int idx = regions[i];
1805     MapArchiveResult result = map_region(idx, addr_delta, mapped_base_address, rs);
1806     if (result != MAP_ARCHIVE_SUCCESS) {
1807       return result;
1808     }
1809     FileMapRegion* r = region_at(idx);
1810     DEBUG_ONLY(if (last_region != nullptr) {
1811         // Ensure that the OS won't be able to allocate new memory spaces between any mapped
1812         // regions, or else it would mess up the simple comparison in MetaspaceObj::is_shared().
1813         assert(r->mapped_base() == last_region->mapped_end(), "must have no gaps");
1814       }
1815       last_region = r;)
1816     log_info(cds)("Mapped %s region #%d at base " INTPTR_FORMAT " top " INTPTR_FORMAT " (%s)", is_static() ? "static " : "dynamic",
1817                   idx, p2i(r->mapped_base()), p2i(r->mapped_end()),
1818                   shared_region_name[idx]);
1819 
1820   }
1821 
1822   header()->set_mapped_base_address(header()->requested_base_address() + addr_delta);
1823   if (addr_delta != 0 && !relocate_pointers_in_core_regions(addr_delta)) {
1824     return MAP_ARCHIVE_OTHER_FAILURE;
1825   }
1826 
1827   return MAP_ARCHIVE_SUCCESS;
1828 }
1829 
1830 bool FileMapInfo::read_region(int i, char* base, size_t size, bool do_commit) {
1831   FileMapRegion* r = region_at(i);
1832   if (do_commit) {
1833     log_info(cds)("Commit %s region #%d at base " INTPTR_FORMAT " top " INTPTR_FORMAT " (%s)%s",
1834                   is_static() ? "static " : "dynamic", i, p2i(base), p2i(base + size),
1835                   shared_region_name[i], r->allow_exec() ? " exec" : "");
1836     if (!os::commit_memory(base, size, r->allow_exec())) {
1837       log_error(cds)("Failed to commit %s region #%d (%s)", is_static() ? "static " : "dynamic",
1838                      i, shared_region_name[i]);
1839       return false;
1840     }
1841   }
1842   if (os::lseek(_fd, (long)r->file_offset(), SEEK_SET) != (int)r->file_offset() ||
1843       read_bytes(base, size) != size) {
1844     return false;
1845   }
1846 
1847   if (VerifySharedSpaces && !r->check_region_crc(base)) {
1848     return false;
1849   }
1850 
1851   r->set_mapped_from_file(false);
1852   r->set_mapped_base(base);
1853 
1854   return true;
1855 }
1856 
1857 MapArchiveResult FileMapInfo::map_region(int i, intx addr_delta, char* mapped_base_address, ReservedSpace rs) {
1858   assert(!HeapShared::is_heap_region(i), "sanity");
1859   FileMapRegion* r = region_at(i);
1860   size_t size = r->used_aligned();
1861   char *requested_addr = mapped_base_address + r->mapping_offset();
1862   assert(r->mapped_base() == nullptr, "must be not mapped yet");
1863   assert(requested_addr != nullptr, "must be specified");
1864 
1865   r->set_mapped_from_file(false);
1866 
1867   if (MetaspaceShared::use_windows_memory_mapping()) {
1868     // Windows cannot remap read-only shared memory to read-write when required for
1869     // RedefineClasses, which is also used by JFR.  Always map windows regions as RW.
1870     r->set_read_only(false);
1871   } else if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space() ||
1872              Arguments::has_jfr_option()) {
1873     // If a tool agent is in use (debugging enabled), or JFR, we must map the address space RW
1874     r->set_read_only(false);
1875   } else if (addr_delta != 0) {
1876     r->set_read_only(false); // Need to patch the pointers
1877   }
1878 
1879   if (MetaspaceShared::use_windows_memory_mapping() && rs.is_reserved()) {
1880     // This is the second time we try to map the archive(s). We have already created a ReservedSpace
1881     // that covers all the FileMapRegions to ensure all regions can be mapped. However, Windows
1882     // can't mmap into a ReservedSpace, so we just ::read() the data. We're going to patch all the
1883     // regions anyway, so there's no benefit for mmap anyway.
1884     if (!read_region(i, requested_addr, size, /* do_commit = */ true)) {
1885       log_info(cds)("Failed to read %s shared space into reserved space at " INTPTR_FORMAT,
1886                     shared_region_name[i], p2i(requested_addr));
1887       return MAP_ARCHIVE_OTHER_FAILURE; // oom or I/O error.
1888     } else {
1889       assert(r->mapped_base() != nullptr, "must be initialized");
1890       return MAP_ARCHIVE_SUCCESS;
1891     }
1892   } else {
1893     // Note that this may either be a "fresh" mapping into unreserved address
1894     // space (Windows, first mapping attempt), or a mapping into pre-reserved
1895     // space (Posix). See also comment in MetaspaceShared::map_archives().

1896     char* base = map_memory(_fd, _full_path, r->file_offset(),
1897                             requested_addr, size, r->read_only(),
1898                             r->allow_exec(), mtClassShared);
1899     if (base != requested_addr) {
1900       log_info(cds)("Unable to map %s shared space at " INTPTR_FORMAT,
1901                     shared_region_name[i], p2i(requested_addr));
1902       _memory_mapping_failed = true;
1903       return MAP_ARCHIVE_MMAP_FAILURE;
1904     }
1905 
1906     if (VerifySharedSpaces && !r->check_region_crc(requested_addr)) {
1907       return MAP_ARCHIVE_OTHER_FAILURE;
1908     }
1909 
1910     r->set_mapped_from_file(true);
1911     r->set_mapped_base(requested_addr);
1912 
1913     return MAP_ARCHIVE_SUCCESS;
1914   }
1915 }
1916 
1917 // The return value is the location of the archive relocation bitmap.
1918 char* FileMapInfo::map_bitmap_region() {
1919   FileMapRegion* r = region_at(MetaspaceShared::bm);
1920   if (r->mapped_base() != nullptr) {
1921     return r->mapped_base();
1922   }
1923   bool read_only = true, allow_exec = false;
1924   char* requested_addr = nullptr; // allow OS to pick any location
1925   char* bitmap_base = map_memory(_fd, _full_path, r->file_offset(),
1926                                  requested_addr, r->used_aligned(), read_only, allow_exec, mtClassShared);
1927   if (bitmap_base == nullptr) {
1928     log_info(cds)("failed to map relocation bitmap");
1929     return nullptr;
1930   }
1931 
1932   if (VerifySharedSpaces && !r->check_region_crc(bitmap_base)) {
1933     log_error(cds)("relocation bitmap CRC error");
1934     if (!os::unmap_memory(bitmap_base, r->used_aligned())) {
1935       fatal("os::unmap_memory of relocation bitmap failed");
1936     }
1937     return nullptr;
1938   }
1939 
1940   r->set_mapped_from_file(true);
1941   r->set_mapped_base(bitmap_base);
1942   log_info(cds)("Mapped %s region #%d at base " INTPTR_FORMAT " top " INTPTR_FORMAT " (%s)",
1943                 is_static() ? "static " : "dynamic",
1944                 MetaspaceShared::bm, p2i(r->mapped_base()), p2i(r->mapped_end()),
1945                 shared_region_name[MetaspaceShared::bm]);
1946   return bitmap_base;
1947 }
1948 








































































1949 // This is called when we cannot map the archive at the requested[ base address (usually 0x800000000).
1950 // We relocate all pointers in the 2 core regions (ro, rw).
1951 bool FileMapInfo::relocate_pointers_in_core_regions(intx addr_delta) {
1952   log_debug(cds, reloc)("runtime archive relocation start");
1953   char* bitmap_base = map_bitmap_region();
1954 
1955   if (bitmap_base == nullptr) {
1956     return false; // OOM, or CRC check failure
1957   } else {
1958     BitMapView rw_ptrmap = ptrmap_view(MetaspaceShared::rw);
1959     BitMapView ro_ptrmap = ptrmap_view(MetaspaceShared::ro);
1960 
1961     FileMapRegion* rw_region = first_core_region();
1962     FileMapRegion* ro_region = last_core_region();
1963 
1964     // Patch all pointers inside the RW region
1965     address rw_patch_base = (address)rw_region->mapped_base();
1966     address rw_patch_end  = (address)rw_region->mapped_end();
1967 
1968     // Patch all pointers inside the RO region
1969     address ro_patch_base = (address)ro_region->mapped_base();
1970     address ro_patch_end  = (address)ro_region->mapped_end();
1971 
1972     // the current value of the pointers to be patched must be within this
1973     // range (i.e., must be between the requested base address and the address of the current archive).
1974     // Note: top archive may point to objects in the base archive, but not the other way around.
1975     address valid_old_base = (address)header()->requested_base_address();
1976     address valid_old_end  = valid_old_base + mapping_end_offset();
1977 
1978     // after patching, the pointers must point inside this range
1979     // (the requested location of the archive, as mapped at runtime).
1980     address valid_new_base = (address)header()->mapped_base_address();
1981     address valid_new_end  = (address)mapped_end();
1982 
1983     SharedDataRelocator rw_patcher((address*)rw_patch_base + header()->rw_ptrmap_start_pos(), (address*)rw_patch_end, valid_old_base, valid_old_end,
1984                                 valid_new_base, valid_new_end, addr_delta);
1985     SharedDataRelocator ro_patcher((address*)ro_patch_base + header()->ro_ptrmap_start_pos(), (address*)ro_patch_end, valid_old_base, valid_old_end,
1986                                 valid_new_base, valid_new_end, addr_delta);
1987     rw_ptrmap.iterate(&rw_patcher);
1988     ro_ptrmap.iterate(&ro_patcher);
1989 
1990     // The MetaspaceShared::bm region will be unmapped in MetaspaceShared::initialize_shared_spaces().
1991 
1992     log_debug(cds, reloc)("runtime archive relocation done");
1993     return true;
1994   }
1995 }
1996 
1997 size_t FileMapInfo::read_bytes(void* buffer, size_t count) {
1998   assert(_file_open, "Archive file is not open");
1999   size_t n = ::read(_fd, buffer, (unsigned int)count);
2000   if (n != count) {
2001     // Close the file if there's a problem reading it.
2002     close();
2003     return 0;
2004   }
2005   _file_offset += count;
2006   return count;
2007 }
2008 
2009 // Get the total size in bytes of a read only region
2010 size_t FileMapInfo::readonly_total() {
2011   size_t total = 0;
2012   if (current_info() != nullptr) {
2013     FileMapRegion* r = FileMapInfo::current_info()->region_at(MetaspaceShared::ro);
2014     if (r->read_only()) total += r->used();
2015   }
2016   if (dynamic_info() != nullptr) {
2017     FileMapRegion* r = FileMapInfo::dynamic_info()->region_at(MetaspaceShared::ro);
2018     if (r->read_only()) total += r->used();
2019   }
2020   return total;
2021 }
2022 
2023 #if INCLUDE_CDS_JAVA_HEAP
2024 MemRegion FileMapInfo::_mapped_heap_memregion;
2025 
2026 bool FileMapInfo::has_heap_region() {
2027   return (region_at(MetaspaceShared::hp)->used() > 0);
2028 }
2029 
2030 // Returns the address range of the archived heap region computed using the
2031 // current oop encoding mode. This range may be different than the one seen at
2032 // dump time due to encoding mode differences. The result is used in determining
2033 // if/how these regions should be relocated at run time.
2034 MemRegion FileMapInfo::get_heap_region_requested_range() {
2035   FileMapRegion* r = region_at(MetaspaceShared::hp);
2036   size_t size = r->used();
2037   assert(size > 0, "must have non-empty heap region");
2038 
2039   address start = heap_region_requested_address();
2040   address end = start + size;
2041   log_info(cds)("Requested heap region [" INTPTR_FORMAT " - " INTPTR_FORMAT "] = "  SIZE_FORMAT_W(8) " bytes",
2042                 p2i(start), p2i(end), size);
2043 
2044   return MemRegion((HeapWord*)start, (HeapWord*)end);
2045 }
2046 
2047 void FileMapInfo::map_or_load_heap_region() {
2048   bool success = false;
2049 
2050   if (can_use_heap_region()) {
2051     if (ArchiveHeapLoader::can_map()) {
2052       success = map_heap_region();
2053     } else if (ArchiveHeapLoader::can_load()) {
2054       success = ArchiveHeapLoader::load_heap_region(this);
2055     } else {
2056       if (!UseCompressedOops && !ArchiveHeapLoader::can_map()) {
2057         // TODO - remove implicit knowledge of G1
2058         log_info(cds)("Cannot use CDS heap data. UseG1GC is required for -XX:-UseCompressedOops");
2059       } else {
2060         log_info(cds)("Cannot use CDS heap data. UseEpsilonGC, UseG1GC, UseSerialGC, UseParallelGC, or UseShenandoahGC are required.");
2061       }
2062     }
2063   }
2064 
2065   if (!success) {
2066     CDSConfig::stop_using_full_module_graph();









2067   }
2068 }
2069 
2070 bool FileMapInfo::can_use_heap_region() {
2071   if (!has_heap_region()) {
2072     return false;
2073   }
2074   if (JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()) {
2075     ShouldNotReachHere(); // CDS should have been disabled.
2076     // The archived objects are mapped at JVM start-up, but we don't know if
2077     // j.l.String or j.l.Class might be replaced by the ClassFileLoadHook,
2078     // which would make the archived String or mirror objects invalid. Let's be safe and not
2079     // use the archived objects. These 2 classes are loaded during the JVMTI "early" stage.
2080     //
2081     // If JvmtiExport::has_early_class_hook_env() is false, the classes of some objects
2082     // in the archived subgraphs may be replaced by the ClassFileLoadHook. But that's OK
2083     // because we won't install an archived object subgraph if the klass of any of the
2084     // referenced objects are replaced. See HeapShared::initialize_from_archived_subgraph().
2085   }
2086 
2087   // We pre-compute narrow Klass IDs with the runtime mapping start intended to be the base, and a shift of
2088   // ArchiveHeapWriter::precomputed_narrow_klass_shift. We enforce this encoding at runtime (see
2089   // CompressedKlassPointers::initialize_for_given_encoding()). Therefore, the following assertions must
2090   // hold:
2091   address archive_narrow_klass_base = (address)header()->mapped_base_address();
2092   const int archive_narrow_klass_shift = ArchiveHeapWriter::precomputed_narrow_klass_shift;
2093 
2094   log_info(cds)("CDS archive was created with max heap size = " SIZE_FORMAT "M, and the following configuration:",
2095                 max_heap_size()/M);
2096   log_info(cds)("    narrow_klass_base at mapping start address, narrow_klass_shift = %d",
2097                 archive_narrow_klass_shift);
2098   log_info(cds)("    narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d",
2099                 narrow_oop_mode(), p2i(narrow_oop_base()), narrow_oop_shift());
2100   log_info(cds)("The current max heap size = " SIZE_FORMAT "M, G1HeapRegion::GrainBytes = " SIZE_FORMAT,
2101                 MaxHeapSize/M, G1HeapRegion::GrainBytes);
2102   log_info(cds)("    narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
2103                 p2i(CompressedKlassPointers::base()), CompressedKlassPointers::shift());
2104   log_info(cds)("    narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d",
2105                 CompressedOops::mode(), p2i(CompressedOops::base()), CompressedOops::shift());
2106   log_info(cds)("    heap range = [" PTR_FORMAT " - "  PTR_FORMAT "]",
2107                 UseCompressedOops ? p2i(CompressedOops::begin()) :
2108                                     UseG1GC ? p2i((address)G1CollectedHeap::heap()->reserved().start()) : 0L,
2109                 UseCompressedOops ? p2i(CompressedOops::end()) :
2110                                     UseG1GC ? p2i((address)G1CollectedHeap::heap()->reserved().end()) : 0L);
2111 
2112   assert(archive_narrow_klass_base == CompressedKlassPointers::base(), "Unexpected encoding base encountered "
2113          "(" PTR_FORMAT ", expected " PTR_FORMAT ")", p2i(CompressedKlassPointers::base()), p2i(archive_narrow_klass_base));
2114   assert(archive_narrow_klass_shift == CompressedKlassPointers::shift(), "Unexpected encoding shift encountered "
2115          "(%d, expected %d)", CompressedKlassPointers::shift(), archive_narrow_klass_shift);
2116 
2117   return true;
2118 }
2119 
2120 // The actual address of this region during dump time.
2121 address FileMapInfo::heap_region_dumptime_address() {
2122   FileMapRegion* r = region_at(MetaspaceShared::hp);
2123   assert(CDSConfig::is_using_archive(), "runtime only");
2124   assert(is_aligned(r->mapping_offset(), sizeof(HeapWord)), "must be");
2125   if (UseCompressedOops) {
2126     return /*dumptime*/ narrow_oop_base() + r->mapping_offset();
2127   } else {
2128     return heap_region_requested_address();
2129   }
2130 }
2131 
2132 // The address where this region can be mapped into the runtime heap without
2133 // patching any of the pointers that are embedded in this region.
2134 address FileMapInfo::heap_region_requested_address() {
2135   assert(CDSConfig::is_using_archive(), "runtime only");
2136   FileMapRegion* r = region_at(MetaspaceShared::hp);
2137   assert(is_aligned(r->mapping_offset(), sizeof(HeapWord)), "must be");
2138   assert(ArchiveHeapLoader::can_map(), "cannot be used by ArchiveHeapLoader::can_load() mode");
2139   if (UseCompressedOops) {
2140     // We can avoid relocation if each region's offset from the runtime CompressedOops::base()
2141     // is the same as its offset from the CompressedOops::base() during dumptime.
2142     // Note that CompressedOops::base() may be different between dumptime and runtime.
2143     //
2144     // Example:
2145     // Dumptime base = 0x1000 and shift is 0. We have a region at address 0x2000. There's a
2146     // narrowOop P stored in this region that points to an object at address 0x2200.
2147     // P's encoded value is 0x1200.
2148     //
2149     // Runtime base = 0x4000 and shift is also 0. If we map this region at 0x5000, then
2150     // the value P can remain 0x1200. The decoded address = (0x4000 + (0x1200 << 0)) = 0x5200,
2151     // which is the runtime location of the referenced object.
2152     return /*runtime*/ CompressedOops::base() + r->mapping_offset();
2153   } else {
2154     // This was the hard-coded requested base address used at dump time. With uncompressed oops,
2155     // the heap range is assigned by the OS so we will most likely have to relocate anyway, no matter
2156     // what base address was picked at duump time.
2157     return (address)ArchiveHeapWriter::NOCOOPS_REQUESTED_BASE;
2158   }
2159 }
2160 
2161 bool FileMapInfo::map_heap_region() {
2162   if (map_heap_region_impl()) {
2163 #ifdef ASSERT
2164     // The "old" regions must be parsable -- we cannot have any unused space
2165     // at the start of the lowest G1 region that contains archived objects.
2166     assert(is_aligned(_mapped_heap_memregion.start(), G1HeapRegion::GrainBytes), "must be");
2167 
2168     // Make sure we map at the very top of the heap - see comments in
2169     // init_heap_region_relocation().
2170     MemRegion heap_range = G1CollectedHeap::heap()->reserved();
2171     assert(heap_range.contains(_mapped_heap_memregion), "must be");
2172 
2173     address heap_end = (address)heap_range.end();
2174     address mapped_heap_region_end = (address)_mapped_heap_memregion.end();
2175     assert(heap_end >= mapped_heap_region_end, "must be");
2176     assert(heap_end - mapped_heap_region_end < (intx)(G1HeapRegion::GrainBytes),
2177            "must be at the top of the heap to avoid fragmentation");
2178 #endif
2179 
2180     ArchiveHeapLoader::set_mapped();
2181     return true;
2182   } else {
2183     return false;
2184   }
2185 }
2186 
2187 bool FileMapInfo::map_heap_region_impl() {
2188   assert(UseG1GC, "the following code assumes G1");
2189 
2190   FileMapRegion* r = region_at(MetaspaceShared::hp);
2191   size_t size = r->used();
2192   if (size == 0) {
2193     return false; // no archived java heap data
2194   }
2195 
2196   size_t word_size = size / HeapWordSize;
2197   address requested_start = heap_region_requested_address();
2198 
2199   log_info(cds)("Preferred address to map heap data (to avoid relocation) is " INTPTR_FORMAT, p2i(requested_start));
2200 
2201   // allocate from java heap
2202   HeapWord* start = G1CollectedHeap::heap()->alloc_archive_region(word_size, (HeapWord*)requested_start);
2203   if (start == nullptr) {
2204     log_info(cds)("UseSharedSpaces: Unable to allocate java heap region for archive heap.");
2205     return false;
2206   }
2207 
2208   _mapped_heap_memregion = MemRegion(start, word_size);
2209 
2210   // Map the archived heap data. No need to call MemTracker::record_virtual_memory_tag()
2211   // for mapped region as it is part of the reserved java heap, which is already recorded.
2212   char* addr = (char*)_mapped_heap_memregion.start();
2213   char* base;
2214 
2215   if (MetaspaceShared::use_windows_memory_mapping()) {
2216     if (!read_region(MetaspaceShared::hp, addr,
2217                      align_up(_mapped_heap_memregion.byte_size(), os::vm_page_size()),
2218                      /* do_commit = */ true)) {
2219       dealloc_heap_region();
2220       log_error(cds)("Failed to read archived heap region into " INTPTR_FORMAT, p2i(addr));
2221       return false;
2222     }
2223     // Checks for VerifySharedSpaces is already done inside read_region()
2224     base = addr;
2225   } else {
2226     base = map_memory(_fd, _full_path, r->file_offset(),
2227                       addr, _mapped_heap_memregion.byte_size(), r->read_only(),
2228                       r->allow_exec());
2229     if (base == nullptr || base != addr) {
2230       dealloc_heap_region();
2231       log_info(cds)("UseSharedSpaces: Unable to map at required address in java heap. "
2232                     INTPTR_FORMAT ", size = " SIZE_FORMAT " bytes",
2233                     p2i(addr), _mapped_heap_memregion.byte_size());
2234       return false;
2235     }
2236 
2237     if (VerifySharedSpaces && !r->check_region_crc(base)) {
2238       dealloc_heap_region();
2239       log_info(cds)("UseSharedSpaces: mapped heap region is corrupt");
2240       return false;
2241     }
2242   }
2243 
2244   r->set_mapped_base(base);
2245 
2246   // If the requested range is different from the range allocated by GC, then
2247   // the pointers need to be patched.
2248   address mapped_start = (address) _mapped_heap_memregion.start();
2249   ptrdiff_t delta = mapped_start - requested_start;
2250   if (UseCompressedOops &&
2251       (narrow_oop_mode() != CompressedOops::mode() ||
2252        narrow_oop_shift() != CompressedOops::shift())) {
2253     _heap_pointers_need_patching = true;
2254   }
2255   if (delta != 0) {
2256     _heap_pointers_need_patching = true;
2257   }
2258   ArchiveHeapLoader::init_mapped_heap_info(mapped_start, delta, narrow_oop_shift());
2259 
2260   if (_heap_pointers_need_patching) {
2261     char* bitmap_base = map_bitmap_region();
2262     if (bitmap_base == nullptr) {
2263       log_info(cds)("CDS heap cannot be used because bitmap region cannot be mapped");
2264       dealloc_heap_region();
2265       unmap_region(MetaspaceShared::hp);
2266       _heap_pointers_need_patching = false;
2267       return false;
2268     }
2269   }
2270   log_info(cds)("Heap data mapped at " INTPTR_FORMAT ", size = " SIZE_FORMAT_W(8) " bytes",
2271                 p2i(mapped_start), _mapped_heap_memregion.byte_size());
2272   log_info(cds)("CDS heap data relocation delta = " INTX_FORMAT " bytes", delta);
2273   return true;
2274 }
2275 
2276 narrowOop FileMapInfo::encoded_heap_region_dumptime_address() {
2277   assert(CDSConfig::is_using_archive(), "runtime only");
2278   assert(UseCompressedOops, "sanity");
2279   FileMapRegion* r = region_at(MetaspaceShared::hp);
2280   return CompressedOops::narrow_oop_cast(r->mapping_offset() >> narrow_oop_shift());
2281 }
2282 
2283 void FileMapInfo::patch_heap_embedded_pointers() {
2284   if (!ArchiveHeapLoader::is_mapped() || !_heap_pointers_need_patching) {
2285     return;
2286   }
2287 
2288   char* bitmap_base = map_bitmap_region();
2289   assert(bitmap_base != nullptr, "must have already been mapped");
2290 
2291   FileMapRegion* r = region_at(MetaspaceShared::hp);
2292   ArchiveHeapLoader::patch_embedded_pointers(
2293       this, _mapped_heap_memregion,
2294       (address)(region_at(MetaspaceShared::bm)->mapped_base()) + r->oopmap_offset(),
2295       r->oopmap_size_in_bits());
2296 }
2297 
2298 void FileMapInfo::fixup_mapped_heap_region() {
2299   if (ArchiveHeapLoader::is_mapped()) {
2300     assert(!_mapped_heap_memregion.is_empty(), "sanity");
2301 
2302     // Populate the archive regions' G1BlockOffsetTables. That ensures
2303     // fast G1BlockOffsetTable::block_start operations for any given address
2304     // within the archive regions when trying to find start of an object
2305     // (e.g. during card table scanning).
2306     G1CollectedHeap::heap()->populate_archive_regions_bot(_mapped_heap_memregion);
2307   }
2308 }
2309 
2310 // dealloc the archive regions from java heap
2311 void FileMapInfo::dealloc_heap_region() {
2312   G1CollectedHeap::heap()->dealloc_archive_regions(_mapped_heap_memregion);
2313 }
2314 #endif // INCLUDE_CDS_JAVA_HEAP
2315 
2316 void FileMapInfo::unmap_regions(int regions[], int num_regions) {
2317   for (int r = 0; r < num_regions; r++) {
2318     int idx = regions[r];
2319     unmap_region(idx);
2320   }
2321 }
2322 
2323 // Unmap a memory region in the address space.
2324 
2325 void FileMapInfo::unmap_region(int i) {
2326   FileMapRegion* r = region_at(i);
2327   char* mapped_base = r->mapped_base();
2328   size_t size = r->used_aligned();
2329 
2330   if (mapped_base != nullptr) {
2331     if (size > 0 && r->mapped_from_file()) {
2332       log_info(cds)("Unmapping region #%d at base " INTPTR_FORMAT " (%s)", i, p2i(mapped_base),
2333                     shared_region_name[i]);
2334       if (!os::unmap_memory(mapped_base, size)) {
2335         fatal("os::unmap_memory failed");
2336       }
2337     }
2338     r->set_mapped_base(nullptr);
2339   }
2340 }
2341 
2342 void FileMapInfo::assert_mark(bool check) {
2343   if (!check) {
2344     MetaspaceShared::unrecoverable_loading_error("Mark mismatch while restoring from shared file.");
2345   }
2346 }
2347 
2348 FileMapInfo* FileMapInfo::_current_info = nullptr;
2349 FileMapInfo* FileMapInfo::_dynamic_archive_info = nullptr;
2350 bool FileMapInfo::_heap_pointers_need_patching = false;
2351 SharedPathTable FileMapInfo::_shared_path_table;
2352 bool FileMapInfo::_validating_shared_path_table = false;
2353 bool FileMapInfo::_memory_mapping_failed = false;
2354 GrowableArray<const char*>* FileMapInfo::_non_existent_class_paths = nullptr;
2355 
2356 // Open the shared archive file, read and validate the header
2357 // information (version, boot classpath, etc.). If initialization
2358 // fails, shared spaces are disabled and the file is closed.
2359 //
2360 // Validation of the archive is done in two steps:
2361 //
2362 // [1] validate_header() - done here.
2363 // [2] validate_shared_path_table - this is done later, because the table is in the RW
2364 //     region of the archive, which is not mapped yet.
2365 bool FileMapInfo::initialize() {
2366   assert(CDSConfig::is_using_archive(), "UseSharedSpaces expected.");
2367   assert(Arguments::has_jimage(), "The shared archive file cannot be used with an exploded module build.");
2368 
2369   if (JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()) {
2370     // CDS assumes that no classes resolved in vmClasses::resolve_all()
2371     // are replaced at runtime by JVMTI ClassFileLoadHook. All of those classes are resolved
2372     // during the JVMTI "early" stage, so we can still use CDS if
2373     // JvmtiExport::has_early_class_hook_env() is false.
2374     log_info(cds)("CDS is disabled because early JVMTI ClassFileLoadHook is in use.");
2375     return false;
2376   }
2377 
2378   if (!open_for_read() || !init_from_file(_fd) || !validate_header()) {
2379     if (_is_static) {
2380       log_info(cds)("Initialize static archive failed.");
2381       return false;
2382     } else {
2383       log_info(cds)("Initialize dynamic archive failed.");
2384       if (AutoCreateSharedArchive) {
2385         CDSConfig::enable_dumping_dynamic_archive();
2386         ArchiveClassesAtExit = CDSConfig::dynamic_archive_path();
2387       }
2388       return false;
2389     }
2390   }
2391 
2392   return true;
2393 }
2394 



























2395 // The 2 core spaces are RW->RO
2396 FileMapRegion* FileMapInfo::first_core_region() const {
2397   return region_at(MetaspaceShared::rw);
2398 }
2399 
2400 FileMapRegion* FileMapInfo::last_core_region() const {
2401   return region_at(MetaspaceShared::ro);
2402 }
2403 
2404 void FileMapInfo::print(outputStream* st) const {
2405   header()->print(st);
2406   if (!is_static()) {
2407     dynamic_header()->print(st);
2408   }
2409 }
2410 
2411 void FileMapHeader::set_as_offset(char* p, size_t *offset) {
2412   *offset = ArchiveBuilder::current()->any_to_offset((address)p);
2413 }
2414 
2415 int FileMapHeader::compute_crc() {
2416   char* start = (char*)this;
2417   // start computing from the field after _header_size to end of base archive name.
2418   char* buf = (char*)&(_generic_header._header_size) + sizeof(_generic_header._header_size);
2419   size_t sz = header_size() - (buf - start);
2420   int crc = ClassLoader::crc32(0, buf, (jint)sz);
2421   return crc;
2422 }
2423 
2424 // This function should only be called during run time with UseSharedSpaces enabled.
2425 bool FileMapHeader::validate() {
2426   if (_obj_alignment != ObjectAlignmentInBytes) {
2427     log_info(cds)("The shared archive file's ObjectAlignmentInBytes of %d"
2428                   " does not equal the current ObjectAlignmentInBytes of %d.",
2429                   _obj_alignment, ObjectAlignmentInBytes);
2430     return false;
2431   }
2432   if (_compact_strings != CompactStrings) {
2433     log_info(cds)("The shared archive file's CompactStrings setting (%s)"
2434                   " does not equal the current CompactStrings setting (%s).",
2435                   _compact_strings ? "enabled" : "disabled",
2436                   CompactStrings   ? "enabled" : "disabled");
2437     return false;
2438   }
2439 
2440   // This must be done after header validation because it might change the
2441   // header data
2442   const char* prop = Arguments::get_property("java.system.class.loader");
2443   if (prop != nullptr) {
2444     log_warning(cds)("Archived non-system classes are disabled because the "
2445             "java.system.class.loader property is specified (value = \"%s\"). "
2446             "To use archived non-system classes, this property must not be set", prop);
2447     _has_platform_or_app_classes = false;
2448   }
2449 
2450 
2451   if (!_verify_local && BytecodeVerificationLocal) {
2452     //  we cannot load boot classes, so there's no point of using the CDS archive
2453     log_info(cds)("The shared archive file's BytecodeVerificationLocal setting (%s)"
2454                                " does not equal the current BytecodeVerificationLocal setting (%s).",
2455                                _verify_local ? "enabled" : "disabled",
2456                                BytecodeVerificationLocal ? "enabled" : "disabled");
2457     return false;
2458   }
2459 
2460   // For backwards compatibility, we don't check the BytecodeVerificationRemote setting
2461   // if the archive only contains system classes.
2462   if (_has_platform_or_app_classes
2463       && !_verify_remote // we didn't verify the archived platform/app classes
2464       && BytecodeVerificationRemote) { // but we want to verify all loaded platform/app classes
2465     log_info(cds)("The shared archive file was created with less restrictive "
2466                                "verification setting than the current setting.");
2467     // Pretend that we didn't have any archived platform/app classes, so they won't be loaded
2468     // by SystemDictionaryShared.
2469     _has_platform_or_app_classes = false;
2470   }
2471 
2472   // Java agents are allowed during run time. Therefore, the following condition is not
2473   // checked: (!_allow_archiving_with_java_agent && AllowArchivingWithJavaAgent)
2474   // Note: _allow_archiving_with_java_agent is set in the shared archive during dump time
2475   // while AllowArchivingWithJavaAgent is set during the current run.
2476   if (_allow_archiving_with_java_agent && !AllowArchivingWithJavaAgent) {
2477     log_warning(cds)("The setting of the AllowArchivingWithJavaAgent is different "
2478                                "from the setting in the shared archive.");
2479     return false;
2480   }
2481 
2482   if (_allow_archiving_with_java_agent) {
2483     log_warning(cds)("This archive was created with AllowArchivingWithJavaAgent. It should be used "
2484             "for testing purposes only and should not be used in a production environment");
2485   }
2486 
2487   log_info(cds)("Archive was created with UseCompressedOops = %d, UseCompressedClassPointers = %d",
2488                           compressed_oops(), compressed_class_pointers());
2489   if (compressed_oops() != UseCompressedOops || compressed_class_pointers() != UseCompressedClassPointers) {
2490     log_info(cds)("Unable to use shared archive.\nThe saved state of UseCompressedOops and UseCompressedClassPointers is "
2491                                "different from runtime, CDS will be disabled.");
2492     return false;
2493   }
2494 
2495   if (! _use_secondary_supers_table && UseSecondarySupersTable) {
2496     log_warning(cds)("The shared archive was created without UseSecondarySupersTable.");
2497     return false;
2498   }
2499 
2500   if (!_use_optimized_module_handling) {
2501     CDSConfig::stop_using_optimized_module_handling();
2502     log_info(cds)("optimized module handling: disabled because archive was created without optimized module handling");
2503   }
2504 
2505   if (is_static() && !_has_full_module_graph) {
2506     // Only the static archive can contain the full module graph.
2507     CDSConfig::stop_using_full_module_graph("archive was created without full module graph");












2508   }
2509 
2510   return true;
2511 }
2512 
2513 bool FileMapInfo::validate_header() {
2514   if (!header()->validate()) {
2515     return false;
2516   }
2517   if (_is_static) {
2518     return true;
2519   } else {
2520     return DynamicArchive::validate(this);
2521   }
2522 }
2523 
2524 #if INCLUDE_JVMTI
2525 ClassPathEntry** FileMapInfo::_classpath_entries_for_jvmti = nullptr;
2526 
2527 ClassPathEntry* FileMapInfo::get_classpath_entry_for_jvmti(int i, TRAPS) {
2528   if (i == 0) {
2529     // index 0 corresponds to the ClassPathImageEntry which is a globally shared object
2530     // and should never be deleted.
2531     return ClassLoader::get_jrt_entry();
2532   }
2533   ClassPathEntry* ent = _classpath_entries_for_jvmti[i];
2534   if (ent == nullptr) {
2535     SharedClassPathEntry* scpe = shared_path(i);
2536     assert(scpe->is_jar(), "must be"); // other types of scpe will not produce archived classes
2537 
2538     const char* path = scpe->name();
2539     struct stat st;
2540     if (os::stat(path, &st) != 0) {
2541       char *msg = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, strlen(path) + 128);
2542       jio_snprintf(msg, strlen(path) + 127, "error in finding JAR file %s", path);
2543       THROW_MSG_(vmSymbols::java_io_IOException(), msg, nullptr);
2544     } else {
2545       ent = ClassLoader::create_class_path_entry(THREAD, path, &st, false, false);
2546       if (ent == nullptr) {
2547         char *msg = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, strlen(path) + 128);
2548         jio_snprintf(msg, strlen(path) + 127, "error in opening JAR file %s", path);
2549         THROW_MSG_(vmSymbols::java_io_IOException(), msg, nullptr);
2550       }
2551     }
2552 
2553     MutexLocker mu(THREAD, CDSClassFileStream_lock);
2554     if (_classpath_entries_for_jvmti[i] == nullptr) {
2555       _classpath_entries_for_jvmti[i] = ent;
2556     } else {
2557       // Another thread has beat me to creating this entry
2558       delete ent;
2559       ent = _classpath_entries_for_jvmti[i];
2560     }
2561   }
2562 
2563   return ent;
2564 }
2565 
2566 ClassFileStream* FileMapInfo::open_stream_for_jvmti(InstanceKlass* ik, Handle class_loader, TRAPS) {
2567   int path_index = ik->shared_classpath_index();
2568   assert(path_index >= 0, "should be called for shared built-in classes only");
2569   assert(path_index < (int)get_number_of_shared_paths(), "sanity");
2570 
2571   ClassPathEntry* cpe = get_classpath_entry_for_jvmti(path_index, CHECK_NULL);
2572   assert(cpe != nullptr, "must be");
2573 
2574   Symbol* name = ik->name();
2575   const char* const class_name = name->as_C_string();
2576   const char* const file_name = ClassLoader::file_name_for_class_name(class_name,
2577                                                                       name->utf8_length());
2578   ClassLoaderData* loader_data = ClassLoaderData::class_loader_data(class_loader());
2579   ClassFileStream* cfs = cpe->open_stream_for_loader(THREAD, file_name, loader_data);
2580   assert(cfs != nullptr, "must be able to read the classfile data of shared classes for built-in loaders.");
2581   log_debug(cds, jvmti)("classfile data for %s [%d: %s] = %d bytes", class_name, path_index,
2582                         cfs->source(), cfs->length());
2583   return cfs;
2584 }
2585 
2586 #endif
--- EOF ---