1 /*
   2  * Copyright (c) 2003, 2026, 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 "cds/aotClassLocation.hpp"
  26 #include "cds/aotLogging.hpp"
  27 #include "cds/aotMappedHeapLoader.hpp"
  28 #include "cds/aotMappedHeapWriter.hpp"
  29 #include "cds/aotMetaspace.hpp"
  30 #include "cds/archiveBuilder.hpp"
  31 #include "cds/archiveUtils.inline.hpp"
  32 #include "cds/cds_globals.hpp"
  33 #include "cds/cdsConfig.hpp"
  34 #include "cds/dynamicArchive.hpp"
  35 #include "cds/filemap.hpp"
  36 #include "cds/heapShared.inline.hpp"
  37 #include "classfile/altHashing.hpp"
  38 #include "classfile/classFileStream.hpp"
  39 #include "classfile/classLoader.hpp"
  40 #include "classfile/classLoader.inline.hpp"
  41 #include "classfile/classLoaderData.inline.hpp"
  42 #include "classfile/symbolTable.hpp"
  43 #include "classfile/systemDictionaryShared.hpp"
  44 #include "classfile/vmClasses.hpp"
  45 #include "classfile/vmSymbols.hpp"
  46 #include "compiler/compilerDefinitions.inline.hpp"
  47 #include "jvm.h"
  48 #include "logging/log.hpp"
  49 #include "logging/logMessage.hpp"
  50 #include "logging/logStream.hpp"
  51 #include "memory/iterator.inline.hpp"
  52 #include "memory/metadataFactory.hpp"
  53 #include "memory/metaspaceClosure.hpp"
  54 #include "memory/oopFactory.hpp"
  55 #include "memory/universe.hpp"
  56 #include "nmt/memTracker.hpp"
  57 #include "oops/access.hpp"
  58 #include "oops/compressedKlass.hpp"
  59 #include "oops/compressedOops.hpp"
  60 #include "oops/compressedOops.inline.hpp"
  61 #include "oops/objArrayOop.hpp"
  62 #include "oops/oop.inline.hpp"
  63 #include "oops/trainingData.hpp"
  64 #include "oops/typeArrayKlass.hpp"
  65 #include "prims/jvmtiExport.hpp"
  66 #include "runtime/arguments.hpp"
  67 #include "runtime/globals_extension.hpp"
  68 #include "runtime/java.hpp"
  69 #include "runtime/javaCalls.hpp"
  70 #include "runtime/mutexLocker.hpp"
  71 #include "runtime/os.hpp"
  72 #include "runtime/vm_version.hpp"
  73 #include "utilities/align.hpp"
  74 #include "utilities/bitMap.inline.hpp"
  75 #include "utilities/classpathStream.hpp"
  76 #include "utilities/defaultStream.hpp"
  77 #include "utilities/ostream.hpp"
  78 #if INCLUDE_G1GC
  79 #include "gc/g1/g1CollectedHeap.hpp"
  80 #include "gc/g1/g1HeapRegion.hpp"
  81 #endif
  82 
  83 #include <errno.h>
  84 #include <sys/stat.h>
  85 
  86 #ifndef O_BINARY       // if defined (Win32) use binary files.
  87 #define O_BINARY 0     // otherwise do nothing.
  88 #endif
  89 
  90 inline void CDSMustMatchFlags::do_print(outputStream* st, bool v) {
  91   st->print("%s", v ? "true" : "false");
  92 }
  93 
  94 #ifdef _LP64
  95 inline void CDSMustMatchFlags::do_print(outputStream* st, uint v) {
  96   st->print("%u", v);
  97 }
  98 #endif
  99 
 100 inline void CDSMustMatchFlags::do_print(outputStream* st, intx v) {
 101   st->print("%zd", v);
 102 }
 103 
 104 inline void CDSMustMatchFlags::do_print(outputStream* st, uintx v) {
 105   st->print("%zu", v);
 106 }
 107 
 108 inline void CDSMustMatchFlags::do_print(outputStream* st, double v) {
 109   st->print("%f", v);
 110 }
 111 
 112 void CDSMustMatchFlags::init() {
 113   assert(CDSConfig::is_dumping_archive(), "sanity");
 114   _max_name_width = 0;
 115 
 116 #define INIT_CDS_MUST_MATCH_FLAG(n) \
 117   _v_##n = n; \
 118   _max_name_width = MAX2(_max_name_width,strlen(#n));
 119   CDS_MUST_MATCH_FLAGS_DO(INIT_CDS_MUST_MATCH_FLAG);
 120 #undef INIT_CDS_MUST_MATCH_FLAG
 121 }
 122 
 123 bool CDSMustMatchFlags::runtime_check() const {
 124 #define CHECK_CDS_MUST_MATCH_FLAG(n) \
 125   if (_v_##n != n) { \
 126     ResourceMark rm; \
 127     stringStream ss; \
 128     ss.print("VM option %s is different between dumptime (", #n);  \
 129     do_print(&ss, _v_ ## n); \
 130     ss.print(") and runtime ("); \
 131     do_print(&ss, n); \
 132     ss.print(")"); \
 133     log_info(cds)("%s", ss.as_string()); \
 134     return false; \
 135   }
 136   CDS_MUST_MATCH_FLAGS_DO(CHECK_CDS_MUST_MATCH_FLAG);
 137 #undef CHECK_CDS_MUST_MATCH_FLAG
 138 
 139   return true;
 140 }
 141 
 142 void CDSMustMatchFlags::print_info() const {
 143   LogTarget(Info, cds) lt;
 144   if (lt.is_enabled()) {
 145     LogStream ls(lt);
 146     ls.print_cr("Recorded VM flags during dumptime:");
 147     print(&ls);
 148   }
 149 }
 150 
 151 void CDSMustMatchFlags::print(outputStream* st) const {
 152 #define PRINT_CDS_MUST_MATCH_FLAG(n) \
 153   st->print("- %-s ", #n);                   \
 154   st->sp(int(_max_name_width - strlen(#n))); \
 155   do_print(st, _v_##n);                      \
 156   st->cr();
 157   CDS_MUST_MATCH_FLAGS_DO(PRINT_CDS_MUST_MATCH_FLAG);
 158 #undef PRINT_CDS_MUST_MATCH_FLAG
 159 }
 160 
 161 // Fill in the fileMapInfo structure with data about this VM instance.
 162 
 163 // This method copies the vm version info into header_version.  If the version is too
 164 // long then a truncated version, which has a hash code appended to it, is copied.
 165 //
 166 // Using a template enables this method to verify that header_version is an array of
 167 // length JVM_IDENT_MAX.  This ensures that the code that writes to the CDS file and
 168 // the code that reads the CDS file will both use the same size buffer.  Hence, will
 169 // use identical truncation.  This is necessary for matching of truncated versions.
 170 template <int N> static void get_header_version(char (&header_version) [N]) {
 171   assert(N == JVM_IDENT_MAX, "Bad header_version size");
 172 
 173   const char *vm_version = VM_Version::internal_vm_info_string();
 174   const int version_len = (int)strlen(vm_version);
 175 
 176   memset(header_version, 0, JVM_IDENT_MAX);
 177 
 178   if (version_len < (JVM_IDENT_MAX-1)) {
 179     strcpy(header_version, vm_version);
 180 
 181   } else {
 182     // Get the hash value.  Use a static seed because the hash needs to return the same
 183     // value over multiple jvm invocations.
 184     uint32_t hash = AltHashing::halfsiphash_32(8191, (const uint8_t*)vm_version, version_len);
 185 
 186     // Truncate the ident, saving room for the 8 hex character hash value.
 187     strncpy(header_version, vm_version, JVM_IDENT_MAX-9);
 188 
 189     // Append the hash code as eight hex digits.
 190     os::snprintf_checked(&header_version[JVM_IDENT_MAX-9], 9, "%08x", hash);
 191   }
 192 
 193   assert(header_version[JVM_IDENT_MAX-1] == 0, "must be");
 194 }
 195 
 196 FileMapInfo::FileMapInfo(const char* full_path, bool is_static) :
 197   _is_static(is_static), _file_open(false), _is_mapped(false), _fd(-1), _file_offset(0),
 198   _full_path(full_path), _base_archive_name(nullptr), _header(nullptr) {
 199   if (_is_static) {
 200     assert(_current_info == nullptr, "must be singleton"); // not thread safe
 201     _current_info = this;
 202   } else {
 203     assert(_dynamic_archive_info == nullptr, "must be singleton"); // not thread safe
 204     _dynamic_archive_info = this;
 205   }
 206 }
 207 
 208 FileMapInfo::~FileMapInfo() {
 209   if (_is_static) {
 210     assert(_current_info == this, "must be singleton"); // not thread safe
 211     _current_info = nullptr;
 212   } else {
 213     assert(_dynamic_archive_info == this, "must be singleton"); // not thread safe
 214     _dynamic_archive_info = nullptr;
 215   }
 216 
 217   if (_header != nullptr) {
 218     os::free(_header);
 219   }
 220 
 221   if (_file_open) {
 222     ::close(_fd);
 223   }
 224 }
 225 
 226 void FileMapInfo::free_current_info() {
 227   assert(CDSConfig::is_dumping_final_static_archive(), "only supported in this mode");
 228   assert(_current_info != nullptr, "sanity");
 229   delete _current_info;
 230   assert(_current_info == nullptr, "sanity"); // Side effect expected from the above "delete" operator.
 231 }
 232 
 233 void FileMapInfo::populate_header(size_t core_region_alignment) {
 234   assert(_header == nullptr, "Sanity check");
 235   size_t c_header_size;
 236   size_t header_size;
 237   size_t base_archive_name_size = 0;
 238   size_t base_archive_name_offset = 0;
 239   if (is_static()) {
 240     c_header_size = sizeof(FileMapHeader);
 241     header_size = c_header_size;
 242   } else {
 243     // dynamic header including base archive name for non-default base archive
 244     c_header_size = sizeof(DynamicArchiveHeader);
 245     header_size = c_header_size;
 246 
 247     const char* default_base_archive_name = CDSConfig::default_archive_path();
 248     const char* current_base_archive_name = CDSConfig::input_static_archive_path();
 249     if (!os::same_files(current_base_archive_name, default_base_archive_name)) {
 250       base_archive_name_size = strlen(current_base_archive_name) + 1;
 251       header_size += base_archive_name_size;
 252       base_archive_name_offset = c_header_size;
 253     }
 254   }
 255   _header = (FileMapHeader*)os::malloc(header_size, mtInternal);
 256   memset((void*)_header, 0, header_size);
 257   _header->populate(this,
 258                     core_region_alignment,
 259                     header_size,
 260                     base_archive_name_size,
 261                     base_archive_name_offset);
 262 }
 263 
 264 void FileMapHeader::populate(FileMapInfo *info, size_t core_region_alignment,
 265                              size_t header_size, size_t base_archive_name_size,
 266                              size_t base_archive_name_offset) {
 267   // 1. We require _generic_header._magic to be at the beginning of the file
 268   // 2. FileMapHeader also assumes that _generic_header is at the beginning of the file
 269   assert(offset_of(FileMapHeader, _generic_header) == 0, "must be");
 270   set_header_size((unsigned int)header_size);
 271   set_base_archive_name_offset((unsigned int)base_archive_name_offset);
 272   set_base_archive_name_size((unsigned int)base_archive_name_size);
 273   if (CDSConfig::is_dumping_dynamic_archive()) {
 274     set_magic(CDS_DYNAMIC_ARCHIVE_MAGIC);
 275   } else if (CDSConfig::is_dumping_preimage_static_archive()) {
 276     set_magic(CDS_PREIMAGE_ARCHIVE_MAGIC);
 277   } else {
 278     set_magic(CDS_ARCHIVE_MAGIC);
 279   }
 280   set_version(CURRENT_CDS_ARCHIVE_VERSION);
 281 
 282   if (!info->is_static() && base_archive_name_size != 0) {
 283     // copy base archive name
 284     copy_base_archive_name(CDSConfig::input_static_archive_path());
 285   }
 286   _core_region_alignment = core_region_alignment;
 287   _obj_alignment = ObjectAlignmentInBytes;
 288   _compact_strings = CompactStrings;
 289   _compact_headers = UseCompactObjectHeaders;
 290 #if INCLUDE_CDS_JAVA_HEAP
 291   if (CDSConfig::is_dumping_heap()) {
 292     _object_streaming_mode = HeapShared::is_writing_streaming_mode();
 293     _narrow_oop_mode = AOTMappedHeapWriter::narrow_oop_mode();
 294     _narrow_oop_base = AOTMappedHeapWriter::narrow_oop_base();
 295     _narrow_oop_shift = AOTMappedHeapWriter::narrow_oop_shift();
 296   }
 297 #endif
 298   _compressed_oops = UseCompressedOops;
 299   _compatible_oop_compression = AOTCompatibleOopCompression;
 300   _narrow_klass_pointer_bits = CompressedKlassPointers::narrow_klass_pointer_bits();
 301   _narrow_klass_shift = ArchiveBuilder::precomputed_narrow_klass_shift();
 302 
 303   // Which JIT compier is used
 304   _compiler_type = (u1)CompilerConfig::compiler_type();
 305   _type_profile_level = TypeProfileLevel;
 306   _type_profile_args_limit = TypeProfileArgsLimit;
 307   _type_profile_parms_limit = TypeProfileParmsLimit;
 308   _type_profile_width = TypeProfileWidth;
 309   _bci_profile_width = BciProfileWidth;
 310   _profile_traps = ProfileTraps;
 311   _type_profile_casts = TypeProfileCasts;
 312   _spec_trap_limit_extra_entries = SpecTrapLimitExtraEntries;
 313   _max_heap_size = MaxHeapSize;
 314   _use_optimized_module_handling = CDSConfig::is_using_optimized_module_handling();
 315   _has_aot_linked_classes = CDSConfig::is_dumping_aot_linked_classes();
 316   _has_full_module_graph = CDSConfig::is_dumping_full_module_graph();
 317   _has_valhalla_patched_classes = Arguments::is_valhalla_enabled();
 318 
 319   // The following fields are for sanity checks for whether this archive
 320   // will function correctly with this JVM and the bootclasspath it's
 321   // invoked with.
 322 
 323   // JVM version string ... changes on each build.
 324   get_header_version(_jvm_ident);
 325 
 326   _verify_local = BytecodeVerificationLocal;
 327   _verify_remote = BytecodeVerificationRemote;
 328   _has_platform_or_app_classes = AOTClassLocationConfig::dumptime()->has_platform_or_app_classes();
 329   _requested_base_address = (char*)SharedBaseAddress;
 330   _mapped_base_address = (char*)SharedBaseAddress;
 331   _must_match.init();
 332 }
 333 
 334 void FileMapHeader::copy_base_archive_name(const char* archive) {
 335   assert(base_archive_name_size() != 0, "_base_archive_name_size not set");
 336   assert(base_archive_name_offset() != 0, "_base_archive_name_offset not set");
 337   assert(header_size() > sizeof(*this), "_base_archive_name_size not included in header size?");
 338   memcpy((char*)this + base_archive_name_offset(), archive, base_archive_name_size());
 339 }
 340 
 341 void FileMapHeader::print(outputStream* st) {
 342   ResourceMark rm;
 343 
 344   st->print_cr("- magic:                          0x%08x", magic());
 345   st->print_cr("- crc:                            0x%08x", crc());
 346   st->print_cr("- version:                        0x%x", version());
 347   st->print_cr("- header_size:                    " UINT32_FORMAT, header_size());
 348   st->print_cr("- base_archive_name_offset:       " UINT32_FORMAT, base_archive_name_offset());
 349   st->print_cr("- base_archive_name_size:         " UINT32_FORMAT, base_archive_name_size());
 350 
 351   for (int i = 0; i < NUM_CDS_REGIONS; i++) {
 352     FileMapRegion* r = region_at(i);
 353     r->print(st, i);
 354   }
 355   st->print_cr("============ end regions ======== ");
 356 
 357   st->print_cr("- core_region_alignment:                    %zu", _core_region_alignment);
 358   st->print_cr("- obj_alignment:                            %d", _obj_alignment);
 359   st->print_cr("- narrow_oop_base:                          " INTPTR_FORMAT, p2i(_narrow_oop_base));
 360   st->print_cr("- narrow_oop_shift                          %d", _narrow_oop_shift);
 361   st->print_cr("- compact_strings:                          %d", _compact_strings);
 362   st->print_cr("- compact_headers:                          %d", _compact_headers);
 363   st->print_cr("- max_heap_size:                            %zu", _max_heap_size);
 364   st->print_cr("- narrow_oop_mode:                          %d", _narrow_oop_mode);
 365   st->print_cr("- compressed_oops:                          %d", _compressed_oops);
 366   st->print_cr("- narrow_klass_pointer_bits:                %d", _narrow_klass_pointer_bits);
 367   st->print_cr("- narrow_klass_shift:                       %d", _narrow_klass_shift);
 368   st->print_cr("- cloned_vtables:                           %u", cast_to_u4(_cloned_vtables));
 369   st->print_cr("- early_serialized_data:                    %u", cast_to_u4(_early_serialized_data));
 370   st->print_cr("- serialized_data:                          %u", cast_to_u4(_serialized_data));
 371   st->print_cr("- jvm_ident:                                %s", _jvm_ident);
 372   st->print_cr("- class_location_config:                    %d", cast_to_u4(_class_location_config));
 373   st->print_cr("- verify_local:                             %d", _verify_local);
 374   st->print_cr("- verify_remote:                            %d", _verify_remote);
 375   st->print_cr("- has_platform_or_app_classes:              %d", _has_platform_or_app_classes);
 376   st->print_cr("- requested_base_address:                   " INTPTR_FORMAT, p2i(_requested_base_address));
 377   st->print_cr("- mapped_base_address:                      " INTPTR_FORMAT, p2i(_mapped_base_address));
 378 
 379   st->print_cr("- object_streaming_mode:                    %d", _object_streaming_mode);
 380   st->print_cr("- mapped_heap_header");
 381   st->print_cr("  - root_segments");
 382   st->print_cr("    - roots_count:                          %d", _mapped_heap_header.root_segments().roots_count());
 383   st->print_cr("    - base_offset:                          0x%zx", _mapped_heap_header.root_segments().base_offset());
 384   st->print_cr("    - count:                                %zu", _mapped_heap_header.root_segments().count());
 385   st->print_cr("    - max_size_elems:                       %d", _mapped_heap_header.root_segments().max_size_in_elems());
 386   st->print_cr("    - max_size_bytes:                       %zu", _mapped_heap_header.root_segments().max_size_in_bytes());
 387   st->print_cr("  - oopmap_start_pos:                       %zu", _mapped_heap_header.oopmap_start_pos());
 388   st->print_cr("  - oopmap_ptrmap_pos:                      %zu", _mapped_heap_header.ptrmap_start_pos());
 389   st->print_cr("- streamed_heap_header");
 390   st->print_cr("  - forwarding_offset:                      %zu", _streamed_heap_header.forwarding_offset());
 391   st->print_cr("  - roots_offset:                           %zu", _streamed_heap_header.roots_offset());
 392   st->print_cr("  - num_roots:                              %zu", _streamed_heap_header.num_roots());
 393   st->print_cr("  - root_highest_object_index_table_offset: %zu", _streamed_heap_header.root_highest_object_index_table_offset());
 394   st->print_cr("  - num_archived_objects:                   %zu", _streamed_heap_header.num_archived_objects());
 395 
 396   st->print_cr("- _rw_ptrmap_start_pos:                     %zu", _rw_ptrmap_start_pos);
 397   st->print_cr("- _ro_ptrmap_start_pos:                     %zu", _ro_ptrmap_start_pos);
 398   st->print_cr("- use_optimized_module_handling:            %d", _use_optimized_module_handling);
 399   st->print_cr("- has_full_module_graph                     %d", _has_full_module_graph);
 400   st->print_cr("- has_valhalla_patched_classes              %d", _has_valhalla_patched_classes);
 401   _must_match.print(st);
 402   st->print_cr("- has_aot_linked_classes                    %d", _has_aot_linked_classes);
 403 }
 404 
 405 bool FileMapInfo::validate_class_location() {
 406   assert(CDSConfig::is_using_archive(), "runtime only");
 407 
 408   AOTClassLocationConfig* config = header()->class_location_config();
 409   bool has_extra_module_paths = false;
 410   if (!config->validate(full_path(), header()->has_aot_linked_classes(), &has_extra_module_paths)) {
 411     if (PrintSharedArchiveAndExit) {
 412       AOTMetaspace::set_archive_loading_failed();
 413       return true;
 414     } else {
 415       return false;
 416     }
 417   }
 418 
 419   if (header()->has_full_module_graph() && has_extra_module_paths) {
 420     CDSConfig::stop_using_optimized_module_handling();
 421     AOTMetaspace::report_loading_error("optimized module handling: disabled because extra module path(s) are specified");
 422   }
 423 
 424   if (CDSConfig::is_dumping_dynamic_archive()) {
 425     // Only support dynamic dumping with the usage of the default CDS archive
 426     // or a simple base archive.
 427     // If the base layer archive contains additional path component besides
 428     // the runtime image and the -cp, dynamic dumping is disabled.
 429     if (config->num_boot_classpaths() > 0) {
 430       CDSConfig::disable_dumping_dynamic_archive();
 431       aot_log_warning(aot)(
 432         "Dynamic archiving is disabled because base layer archive has appended boot classpath");
 433     }
 434     if (config->num_module_paths() > 0) {
 435       if (has_extra_module_paths) {
 436         CDSConfig::disable_dumping_dynamic_archive();
 437         aot_log_warning(aot)(
 438           "Dynamic archiving is disabled because base layer archive has a different module path");
 439       }
 440     }
 441   }
 442 
 443 #if INCLUDE_JVMTI
 444   if (_classpath_entries_for_jvmti != nullptr) {
 445     os::free(_classpath_entries_for_jvmti);
 446   }
 447   size_t sz = sizeof(ClassPathEntry*) * AOTClassLocationConfig::runtime()->length();
 448   _classpath_entries_for_jvmti = (ClassPathEntry**)os::malloc(sz, mtClass);
 449   memset((void*)_classpath_entries_for_jvmti, 0, sz);
 450 #endif
 451 
 452   return true;
 453 }
 454 
 455 // A utility class for reading/validating the GenericCDSFileMapHeader portion of
 456 // a CDS archive's header. The file header of all CDS archives with versions from
 457 // CDS_GENERIC_HEADER_SUPPORTED_MIN_VERSION (12) are guaranteed to always start
 458 // with GenericCDSFileMapHeader. This makes it possible to read important information
 459 // from a CDS archive created by a different version of HotSpot, so that we can
 460 // automatically regenerate the archive as necessary (JDK-8261455).
 461 class FileHeaderHelper {
 462   int _fd;
 463   bool _is_valid;
 464   bool _is_static;
 465   GenericCDSFileMapHeader* _header;
 466   const char* _archive_name;
 467   const char* _base_archive_name;
 468 
 469 public:
 470   FileHeaderHelper(const char* archive_name, bool is_static) {
 471     _fd = -1;
 472     _is_valid = false;
 473     _header = nullptr;
 474     _base_archive_name = nullptr;
 475     _archive_name = archive_name;
 476     _is_static = is_static;
 477   }
 478 
 479   ~FileHeaderHelper() {
 480     if (_header != nullptr) {
 481       FREE_C_HEAP_ARRAY(_header);
 482     }
 483     if (_fd != -1) {
 484       ::close(_fd);
 485     }
 486   }
 487 
 488   bool initialize() {
 489     assert(_archive_name != nullptr, "Archive name is null");
 490     _fd = os::open(_archive_name, O_RDONLY | O_BINARY, 0);
 491     if (_fd < 0) {
 492       AOTMetaspace::report_loading_error("Specified %s not found (%s)", CDSConfig::type_of_archive_being_loaded(), _archive_name);
 493       return false;
 494     }
 495     return initialize(_fd);
 496   }
 497 
 498   // for an already opened file, do not set _fd
 499   bool initialize(int fd) {
 500     assert(_archive_name != nullptr, "Archive name is null");
 501     assert(fd != -1, "Archive must be opened already");
 502     // First read the generic header so we know the exact size of the actual header.
 503     const char* file_type = CDSConfig::type_of_archive_being_loaded();
 504     GenericCDSFileMapHeader gen_header;
 505     size_t size = sizeof(GenericCDSFileMapHeader);
 506     os::lseek(fd, 0, SEEK_SET);
 507     size_t n = ::read(fd, (void*)&gen_header, (unsigned int)size);
 508     if (n != size) {
 509       aot_log_warning(aot)("Unable to read generic CDS file map header from %s", file_type);
 510       return false;
 511     }
 512 
 513     if (gen_header._magic != CDS_ARCHIVE_MAGIC &&
 514         gen_header._magic != CDS_DYNAMIC_ARCHIVE_MAGIC &&
 515         gen_header._magic != CDS_PREIMAGE_ARCHIVE_MAGIC) {
 516       aot_log_warning(aot)("The %s has a bad magic number: %#x", file_type, gen_header._magic);
 517       return false;
 518     }
 519 
 520     if (gen_header._version < CDS_GENERIC_HEADER_SUPPORTED_MIN_VERSION) {
 521       aot_log_warning(aot)("Cannot handle %s version 0x%x. Must be at least 0x%x.",
 522                        file_type, gen_header._version, CDS_GENERIC_HEADER_SUPPORTED_MIN_VERSION);
 523       return false;
 524     }
 525 
 526     if (gen_header._version !=  CURRENT_CDS_ARCHIVE_VERSION) {
 527       aot_log_warning(aot)("The %s version 0x%x does not match the required version 0x%x.",
 528                        file_type, gen_header._version, CURRENT_CDS_ARCHIVE_VERSION);
 529     }
 530 
 531     size_t filelen = os::lseek(fd, 0, SEEK_END);
 532     if (gen_header._header_size >= filelen) {
 533       aot_log_warning(aot)("Archive file header larger than archive file");
 534       return false;
 535     }
 536 
 537     // Read the actual header and perform more checks
 538     size = gen_header._header_size;
 539     _header = (GenericCDSFileMapHeader*)NEW_C_HEAP_ARRAY(char, size, mtInternal);
 540     os::lseek(fd, 0, SEEK_SET);
 541     n = ::read(fd, (void*)_header, (unsigned int)size);
 542     if (n != size) {
 543       aot_log_warning(aot)("Unable to read file map header from %s", file_type);
 544       return false;
 545     }
 546 
 547     if (!check_header_crc()) {
 548       return false;
 549     }
 550 
 551     if (!check_and_init_base_archive_name()) {
 552       return false;
 553     }
 554 
 555     // All fields in the GenericCDSFileMapHeader has been validated.
 556     _is_valid = true;
 557     return true;
 558   }
 559 
 560   GenericCDSFileMapHeader* get_generic_file_header() {
 561     assert(_header != nullptr && _is_valid, "must be a valid archive file");
 562     return _header;
 563   }
 564 
 565   const char* base_archive_name() {
 566     assert(_header != nullptr && _is_valid, "must be a valid archive file");
 567     return _base_archive_name;
 568   }
 569 
 570   bool is_static_archive() const {
 571     return _header->_magic == CDS_ARCHIVE_MAGIC;
 572   }
 573 
 574   bool is_dynamic_archive() const {
 575     return _header->_magic == CDS_DYNAMIC_ARCHIVE_MAGIC;
 576   }
 577 
 578   bool is_preimage_static_archive() const {
 579     return _header->_magic == CDS_PREIMAGE_ARCHIVE_MAGIC;
 580   }
 581 
 582  private:
 583   bool check_header_crc() const {
 584     if (VerifySharedSpaces) {
 585       FileMapHeader* header = (FileMapHeader*)_header;
 586       int actual_crc = header->compute_crc();
 587       if (actual_crc != header->crc()) {
 588         aot_log_info(aot)("_crc expected: %d", header->crc());
 589         aot_log_info(aot)("       actual: %d", actual_crc);
 590         aot_log_warning(aot)("Header checksum verification failed.");
 591         return false;
 592       }
 593     }
 594     return true;
 595   }
 596 
 597   bool check_and_init_base_archive_name() {
 598     unsigned int name_offset = _header->_base_archive_name_offset;
 599     unsigned int name_size   = _header->_base_archive_name_size;
 600     unsigned int header_size = _header->_header_size;
 601 
 602     if (name_offset + name_size < name_offset) {
 603       aot_log_warning(aot)("base_archive_name offset/size overflow: " UINT32_FORMAT "/" UINT32_FORMAT,
 604                                  name_offset, name_size);
 605       return false;
 606     }
 607 
 608     if (is_static_archive() || is_preimage_static_archive()) {
 609       if (name_offset != 0) {
 610         aot_log_warning(aot)("static shared archive must have zero _base_archive_name_offset");
 611         return false;
 612       }
 613       if (name_size != 0) {
 614         aot_log_warning(aot)("static shared archive must have zero _base_archive_name_size");
 615         return false;
 616       }
 617     } else {
 618       assert(is_dynamic_archive(), "must be");
 619       if ((name_size == 0 && name_offset != 0) ||
 620           (name_size != 0 && name_offset == 0)) {
 621         // If either is zero, both must be zero. This indicates that we are using the default base archive.
 622         aot_log_warning(aot)("Invalid base_archive_name offset/size: " UINT32_FORMAT "/" UINT32_FORMAT,
 623                                    name_offset, name_size);
 624         return false;
 625       }
 626       if (name_size > 0) {
 627         if (name_offset + name_size > header_size) {
 628           aot_log_warning(aot)("Invalid base_archive_name offset/size (out of range): "
 629                                      UINT32_FORMAT " + " UINT32_FORMAT " > " UINT32_FORMAT ,
 630                                      name_offset, name_size, header_size);
 631           return false;
 632         }
 633         const char* name = ((const char*)_header) + _header->_base_archive_name_offset;
 634         if (name[name_size - 1] != '\0' || strlen(name) != name_size - 1) {
 635           aot_log_warning(aot)("Base archive name is damaged");
 636           return false;
 637         }
 638         if (!os::file_exists(name)) {
 639           aot_log_warning(aot)("Base archive %s does not exist", name);
 640           return false;
 641         }
 642         _base_archive_name = name;
 643       }
 644     }
 645 
 646     return true;
 647   }
 648 };
 649 
 650 // Return value:
 651 // false:
 652 //      <archive_name> is not a valid archive. *base_archive_name is set to null.
 653 // true && (*base_archive_name) == nullptr:
 654 //      <archive_name> is a valid static archive.
 655 // true && (*base_archive_name) != nullptr:
 656 //      <archive_name> is a valid dynamic archive.
 657 bool FileMapInfo::get_base_archive_name_from_header(const char* archive_name,
 658                                                     const char** base_archive_name) {
 659   FileHeaderHelper file_helper(archive_name, false);
 660   *base_archive_name = nullptr;
 661 
 662   if (!file_helper.initialize()) {
 663     return false;
 664   }
 665   GenericCDSFileMapHeader* header = file_helper.get_generic_file_header();
 666   switch (header->_magic) {
 667   case CDS_PREIMAGE_ARCHIVE_MAGIC:
 668     return false; // This is a binary config file, not a proper archive
 669   case CDS_DYNAMIC_ARCHIVE_MAGIC:
 670     break;
 671   default:
 672     assert(header->_magic == CDS_ARCHIVE_MAGIC, "must be");
 673     if (AutoCreateSharedArchive) {
 674      aot_log_warning(aot)("AutoCreateSharedArchive is ignored because %s is a static archive", archive_name);
 675     }
 676     return true;
 677   }
 678 
 679   const char* base = file_helper.base_archive_name();
 680   if (base == nullptr) {
 681     *base_archive_name = CDSConfig::default_archive_path();
 682   } else {
 683     *base_archive_name = os::strdup_check_oom(base);
 684   }
 685 
 686   return true;
 687 }
 688 
 689 bool FileMapInfo::is_preimage_static_archive(const char* file) {
 690   FileHeaderHelper file_helper(file, false);
 691   if (!file_helper.initialize()) {
 692     return false;
 693   }
 694   return file_helper.is_preimage_static_archive();
 695 }
 696 
 697 // Read the FileMapInfo information from the file.
 698 
 699 bool FileMapInfo::init_from_file(int fd) {
 700   FileHeaderHelper file_helper(_full_path, _is_static);
 701   if (!file_helper.initialize(fd)) {
 702     aot_log_warning(aot)("Unable to read the file header.");
 703     return false;
 704   }
 705   GenericCDSFileMapHeader* gen_header = file_helper.get_generic_file_header();
 706 
 707   const char* file_type = CDSConfig::type_of_archive_being_loaded();
 708   if (_is_static) {
 709     if ((gen_header->_magic == CDS_ARCHIVE_MAGIC) ||
 710         (gen_header->_magic == CDS_PREIMAGE_ARCHIVE_MAGIC && CDSConfig::is_dumping_final_static_archive())) {
 711       // Good
 712     } else {
 713       if (CDSConfig::new_aot_flags_used()) {
 714         aot_log_warning(aot)("Not a valid %s (%s)", file_type, _full_path);
 715       } else {
 716         aot_log_warning(aot)("Not a base shared archive: %s", _full_path);
 717       }
 718       return false;
 719     }
 720   } else {
 721     if (gen_header->_magic != CDS_DYNAMIC_ARCHIVE_MAGIC) {
 722       aot_log_warning(aot)("Not a top shared archive: %s", _full_path);
 723       return false;
 724     }
 725   }
 726 
 727   _header = (FileMapHeader*)os::malloc(gen_header->_header_size, mtInternal);
 728   os::lseek(fd, 0, SEEK_SET); // reset to begin of the archive
 729   size_t size = gen_header->_header_size;
 730   size_t n = ::read(fd, (void*)_header, (unsigned int)size);
 731   if (n != size) {
 732     aot_log_warning(aot)("Failed to read file header from the top archive file\n");
 733     return false;
 734   }
 735 
 736   if (header()->version() != CURRENT_CDS_ARCHIVE_VERSION) {
 737     aot_log_info(aot)("_version expected: 0x%x", CURRENT_CDS_ARCHIVE_VERSION);
 738     aot_log_info(aot)("           actual: 0x%x", header()->version());
 739     aot_log_warning(aot)("The %s has the wrong version.", file_type);
 740     return false;
 741   }
 742 
 743   unsigned int base_offset = header()->base_archive_name_offset();
 744   unsigned int name_size = header()->base_archive_name_size();
 745   unsigned int header_size = header()->header_size();
 746   if (base_offset != 0 && name_size != 0) {
 747     if (header_size != base_offset + name_size) {
 748       aot_log_info(aot)("_header_size: " UINT32_FORMAT, header_size);
 749       aot_log_info(aot)("base_archive_name_size: " UINT32_FORMAT, header()->base_archive_name_size());
 750       aot_log_info(aot)("base_archive_name_offset: " UINT32_FORMAT, header()->base_archive_name_offset());
 751       aot_log_warning(aot)("The %s has an incorrect header size.", file_type);
 752       return false;
 753     }
 754   }
 755 
 756   const char* actual_ident = header()->jvm_ident();
 757 
 758   if (actual_ident[JVM_IDENT_MAX-1] != 0) {
 759     aot_log_warning(aot)("JVM version identifier is corrupted.");
 760     return false;
 761   }
 762 
 763   char expected_ident[JVM_IDENT_MAX];
 764   get_header_version(expected_ident);
 765   if (strncmp(actual_ident, expected_ident, JVM_IDENT_MAX-1) != 0) {
 766     aot_log_info(aot)("_jvm_ident expected: %s", expected_ident);
 767     aot_log_info(aot)("             actual: %s", actual_ident);
 768     aot_log_warning(aot)("The %s was created by a different"
 769                   " version or build of HotSpot", file_type);
 770     return false;
 771   }
 772 
 773   _file_offset = header()->header_size(); // accounts for the size of _base_archive_name
 774 
 775   size_t len = os::lseek(fd, 0, SEEK_END);
 776 
 777   for (int i = 0; i < AOTMetaspace::n_regions; i++) {
 778     FileMapRegion* r = region_at(i);
 779     if (r->file_offset() > len || len - r->file_offset() < r->used()) {
 780       aot_log_warning(aot)("The %s has been truncated.", file_type);
 781       return false;
 782     }
 783   }
 784 
 785   if (!header()->check_must_match_flags()) {
 786     return false;
 787   }
 788 
 789   return true;
 790 }
 791 
 792 void FileMapInfo::seek_to_position(size_t pos) {
 793   if (os::lseek(_fd, (jlong)pos, SEEK_SET) < 0) {
 794     aot_log_error(aot)("Unable to seek to position %zu (errno=%d: %s)", pos, errno, os::strerror(errno));
 795     AOTMetaspace::unrecoverable_loading_error();
 796   }
 797 }
 798 
 799 // Read the FileMapInfo information from the file.
 800 bool FileMapInfo::open_for_read() {
 801   if (_file_open) {
 802     return true;
 803   }
 804   const char* file_type = CDSConfig::type_of_archive_being_loaded();
 805   const char* info = CDSConfig::is_dumping_final_static_archive() ?
 806     "AOTConfiguration file " : "";
 807   aot_log_info(aot)("trying to map %s%s", info, _full_path);
 808   int fd = os::open(_full_path, O_RDONLY | O_BINARY, 0);
 809   if (fd < 0) {
 810     if (errno == ENOENT) {
 811       aot_log_info(aot)("Specified %s not found (%s)", file_type, _full_path);
 812     } else {
 813       aot_log_warning(aot)("Failed to open %s (%s)", file_type,
 814                     os::strerror(errno));
 815     }
 816     return false;
 817   } else {
 818     aot_log_info(aot)("Opened %s %s.", file_type, _full_path);
 819   }
 820 
 821   _fd = fd;
 822   _file_open = true;
 823   return true;
 824 }
 825 
 826 // Write the FileMapInfo information to the file.
 827 
 828 void FileMapInfo::open_as_output() {
 829   if (CDSConfig::new_aot_flags_used()) {
 830     if (CDSConfig::is_dumping_preimage_static_archive()) {
 831       log_info(aot)("Writing binary AOTConfiguration file: %s",  _full_path);
 832     } else {
 833       log_info(aot)("Writing AOTCache file: %s",  _full_path);
 834     }
 835   } else {
 836     aot_log_info(aot)("Dumping shared data to file: %s", _full_path);
 837   }
 838 
 839 #ifdef _WINDOWS  // On Windows, need WRITE permission to remove the file.
 840   chmod(_full_path, _S_IREAD | _S_IWRITE);
 841 #endif
 842 
 843   // Use remove() to delete the existing file because, on Unix, this will
 844   // allow processes that have it open continued access to the file.
 845   remove(_full_path);
 846   int fd = os::open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0666);
 847   if (fd < 0) {
 848     aot_log_error(aot)("Unable to create %s %s: (%s).", CDSConfig::type_of_archive_being_written(), _full_path,
 849                    os::strerror(errno));
 850     AOTMetaspace::writing_error();
 851     return;
 852   }
 853   _fd = fd;
 854   _file_open = true;
 855 }
 856 
 857 void FileMapInfo::prepare_for_writing() {
 858   // Seek past the header. We will write the header after all regions are written
 859   // and their CRCs computed.
 860   size_t header_bytes = header()->header_size();
 861 
 862   header_bytes = align_up(header_bytes, AOTMetaspace::core_region_alignment());
 863   _file_offset = header_bytes;
 864   seek_to_position(_file_offset);
 865 }
 866 
 867 // Write the header to the file, seek to the next allocation boundary.
 868 
 869 void FileMapInfo::write_header() {
 870   _file_offset = 0;
 871   seek_to_position(_file_offset);
 872   assert(is_file_position_aligned(), "must be");
 873   write_bytes(header(), header()->header_size());
 874 }
 875 
 876 size_t FileMapRegion::used_aligned() const {
 877   return align_up(used(), AOTMetaspace::core_region_alignment());
 878 }
 879 
 880 void FileMapRegion::init(int region_index, size_t mapping_offset, size_t size, bool read_only,
 881                          bool allow_exec, int crc) {
 882   _is_heap_region = HeapShared::is_heap_region(region_index);
 883   _is_bitmap_region = (region_index == AOTMetaspace::bm);
 884   _mapping_offset = mapping_offset;
 885   _used = size;
 886   _read_only = read_only;
 887   _allow_exec = allow_exec;
 888   _crc = crc;
 889   _mapped_from_file = false;
 890   _mapped_base = nullptr;
 891   _in_reserved_space = false;
 892 }
 893 
 894 void FileMapRegion::init_oopmap(size_t offset, size_t size_in_bits) {
 895   _oopmap_offset = offset;
 896   _oopmap_size_in_bits = size_in_bits;
 897 }
 898 
 899 void FileMapRegion::init_ptrmap(size_t offset, size_t size_in_bits) {
 900   _ptrmap_offset = offset;
 901   _ptrmap_size_in_bits = size_in_bits;
 902 }
 903 
 904 bool FileMapRegion::check_region_crc(char* base) const {
 905   // This function should be called after the region has been properly
 906   // loaded into memory via FileMapInfo::map_region() or FileMapInfo::read_region().
 907   // I.e., this->mapped_base() must be valid.
 908   size_t sz = used();
 909   if (sz == 0) {
 910     return true;
 911   }
 912 
 913   assert(base != nullptr, "must be initialized");
 914   int crc = ClassLoader::crc32(0, base, (jint)sz);
 915   if (crc != this->crc()) {
 916     aot_log_warning(aot)("Checksum verification failed.");
 917     return false;
 918   }
 919   return true;
 920 }
 921 
 922 static const char* region_name(int region_index) {
 923   static const char* names[] = {
 924     "rw", "ro", "bm", "hp", "ac"
 925   };
 926   const int num_regions = sizeof(names)/sizeof(names[0]);
 927   assert(0 <= region_index && region_index < num_regions, "sanity");
 928 
 929   return names[region_index];
 930 }
 931 
 932 BitMapView FileMapInfo::bitmap_view(int region_index, bool is_oopmap) {
 933   FileMapRegion* r = region_at(region_index);
 934   char* bitmap_base = is_static() ? FileMapInfo::current_info()->map_bitmap_region() : FileMapInfo::dynamic_info()->map_bitmap_region();
 935   bitmap_base += is_oopmap ? r->oopmap_offset() : r->ptrmap_offset();
 936   size_t size_in_bits = is_oopmap ? r->oopmap_size_in_bits() : r->ptrmap_size_in_bits();
 937 
 938   aot_log_debug(aot, reloc)("mapped %s relocation %smap @ " INTPTR_FORMAT " (%zu bits)",
 939                         region_name(region_index), is_oopmap ? "oop" : "ptr",
 940                         p2i(bitmap_base), size_in_bits);
 941 
 942   return BitMapView((BitMap::bm_word_t*)(bitmap_base), size_in_bits);
 943 }
 944 
 945 BitMapView FileMapInfo::oopmap_view(int region_index) {
 946     return bitmap_view(region_index, /*is_oopmap*/true);
 947   }
 948 
 949 BitMapView FileMapInfo::ptrmap_view(int region_index) {
 950   return bitmap_view(region_index, /*is_oopmap*/false);
 951 }
 952 
 953 void FileMapRegion::print(outputStream* st, int region_index) {
 954   st->print_cr("============ region ============= %d \"%s\"", region_index, region_name(region_index));
 955   st->print_cr("- crc:                            0x%08x", _crc);
 956   st->print_cr("- read_only:                      %d", _read_only);
 957   st->print_cr("- allow_exec:                     %d", _allow_exec);
 958   st->print_cr("- is_heap_region:                 %d", _is_heap_region);
 959   st->print_cr("- is_bitmap_region:               %d", _is_bitmap_region);
 960   st->print_cr("- mapped_from_file:               %d", _mapped_from_file);
 961   st->print_cr("- file_offset:                    0x%zx", _file_offset);
 962   st->print_cr("- mapping_offset:                 0x%zx", _mapping_offset);
 963   st->print_cr("- used:                           %zu", _used);
 964   st->print_cr("- oopmap_offset:                  0x%zx", _oopmap_offset);
 965   st->print_cr("- oopmap_size_in_bits:            %zu", _oopmap_size_in_bits);
 966   st->print_cr("- ptrmap_offset:                  0x%zx", _ptrmap_offset);
 967   st->print_cr("- ptrmap_size_in_bits:            %zu", _ptrmap_size_in_bits);
 968   st->print_cr("- mapped_base:                    " INTPTR_FORMAT, p2i(_mapped_base));
 969 }
 970 
 971 void FileMapInfo::write_region(int region, char* base, size_t size,
 972                                bool read_only, bool allow_exec) {
 973   assert(CDSConfig::is_dumping_archive(), "sanity");
 974 
 975   FileMapRegion* r = region_at(region);
 976   char* requested_base;
 977   size_t mapping_offset = 0;
 978 
 979   if (region == AOTMetaspace::bm) {
 980     requested_base = nullptr; // always null for bm region
 981   } else if (size == 0) {
 982     // This is an unused region (e.g., a heap region when !INCLUDE_CDS_JAVA_HEAP)
 983     requested_base = nullptr;
 984   } else if (HeapShared::is_heap_region(region)) {
 985     assert(CDSConfig::is_dumping_heap(), "sanity");
 986 #if INCLUDE_CDS_JAVA_HEAP
 987     assert(!CDSConfig::is_dumping_dynamic_archive(), "must be");
 988     if (HeapShared::is_writing_mapping_mode()) {
 989       requested_base = (char*)AOTMappedHeapWriter::requested_address();
 990       if (UseCompressedOops) {
 991         mapping_offset = (size_t)((address)requested_base - AOTMappedHeapWriter::narrow_oop_base());
 992         assert((mapping_offset >> CompressedOops::shift()) << CompressedOops::shift() == mapping_offset, "must be");
 993       }
 994     } else {
 995       requested_base = nullptr;
 996     }
 997 #endif // INCLUDE_CDS_JAVA_HEAP
 998   } else {
 999     char* requested_SharedBaseAddress = (char*)AOTMetaspace::requested_base_address();
1000     requested_base = ArchiveBuilder::current()->to_requested(base);
1001     assert(requested_base >= requested_SharedBaseAddress, "must be");
1002     mapping_offset = requested_base - requested_SharedBaseAddress;
1003   }
1004 
1005   r->set_file_offset(_file_offset);
1006   int crc = ClassLoader::crc32(0, base, (jint)size);
1007   if (size > 0) {
1008     aot_log_info(aot)("Shared file region (%s) %d: %8zu"
1009                    " bytes, addr " INTPTR_FORMAT " file offset 0x%08" PRIxPTR
1010                    " crc 0x%08x",
1011                    region_name(region), region, size, p2i(requested_base), _file_offset, crc);
1012   } else {
1013     aot_log_info(aot)("Shared file region (%s) %d: %8zu"
1014                    " bytes", region_name(region), region, size);
1015   }
1016 
1017   r->init(region, mapping_offset, size, read_only, allow_exec, crc);
1018 
1019   if (base != nullptr) {
1020     write_bytes_aligned(base, size);
1021   }
1022 }
1023 
1024 static size_t write_bitmap(const CHeapBitMap* map, char* output, size_t offset) {
1025   size_t size_in_bytes = map->size_in_bytes();
1026   map->write_to((BitMap::bm_word_t*)(output + offset), size_in_bytes);
1027   return offset + size_in_bytes;
1028 }
1029 
1030 // The sorting code groups the objects with non-null oop/ptrs together.
1031 // Relevant bitmaps then have lots of leading and trailing zeros, which
1032 // we do not have to store.
1033 size_t FileMapInfo::remove_bitmap_zeros(CHeapBitMap* map) {
1034   BitMap::idx_t first_set = map->find_first_set_bit(0);
1035   BitMap::idx_t last_set  = map->find_last_set_bit(0);
1036   size_t old_size = map->size();
1037 
1038   // Slice and resize bitmap
1039   map->truncate(first_set, last_set + 1);
1040 
1041   assert(map->at(0), "First bit should be set");
1042   assert(map->at(map->size() - 1), "Last bit should be set");
1043   assert(map->size() <= old_size, "sanity");
1044 
1045   return first_set;
1046 }
1047 
1048 char* FileMapInfo::write_bitmap_region(CHeapBitMap* rw_ptrmap,
1049                                        CHeapBitMap* ro_ptrmap,
1050                                        AOTMappedHeapInfo* mapped_heap_info,
1051                                        AOTStreamedHeapInfo* streamed_heap_info,
1052                                        size_t &size_in_bytes) {
1053   size_t removed_rw_leading_zeros = remove_bitmap_zeros(rw_ptrmap);
1054   size_t removed_ro_leading_zeros = remove_bitmap_zeros(ro_ptrmap);
1055   header()->set_rw_ptrmap_start_pos(removed_rw_leading_zeros);
1056   header()->set_ro_ptrmap_start_pos(removed_ro_leading_zeros);
1057   size_in_bytes = rw_ptrmap->size_in_bytes() + ro_ptrmap->size_in_bytes();
1058 
1059   if (mapped_heap_info != nullptr && mapped_heap_info->is_used()) {
1060     // Remove leading and trailing zeros
1061     assert(HeapShared::is_writing_mapping_mode(), "unexpected dumping mode");
1062     size_t removed_oop_leading_zeros = remove_bitmap_zeros(mapped_heap_info->oopmap());
1063     size_t removed_ptr_leading_zeros = remove_bitmap_zeros(mapped_heap_info->ptrmap());
1064     mapped_heap_info->set_oopmap_start_pos(removed_oop_leading_zeros);
1065     mapped_heap_info->set_ptrmap_start_pos(removed_ptr_leading_zeros);
1066 
1067     size_in_bytes += mapped_heap_info->oopmap()->size_in_bytes();
1068     size_in_bytes += mapped_heap_info->ptrmap()->size_in_bytes();
1069   } else if (streamed_heap_info != nullptr && streamed_heap_info->is_used()) {
1070     assert(HeapShared::is_writing_streaming_mode(), "unexpected dumping mode");
1071 
1072     size_in_bytes += streamed_heap_info->oopmap()->size_in_bytes();
1073   }
1074 
1075   // The bitmap region contains up to 4 parts:
1076   // rw_ptrmap:                  metaspace pointers inside the read-write region
1077   // ro_ptrmap:                  metaspace pointers inside the read-only region
1078   // *_heap_info->oopmap():      Java oop pointers in the heap region
1079   // mapped_heap_info->ptrmap(): metaspace pointers in the heap region
1080   char* buffer = NEW_C_HEAP_ARRAY(char, size_in_bytes, mtClassShared);
1081   size_t written = 0;
1082 
1083   region_at(AOTMetaspace::rw)->init_ptrmap(0, rw_ptrmap->size());
1084   written = write_bitmap(rw_ptrmap, buffer, written);
1085 
1086   region_at(AOTMetaspace::ro)->init_ptrmap(written, ro_ptrmap->size());
1087   written = write_bitmap(ro_ptrmap, buffer, written);
1088 
1089   if (mapped_heap_info != nullptr && mapped_heap_info->is_used()) {
1090     assert(HeapShared::is_writing_mapping_mode(), "unexpected dumping mode");
1091     FileMapRegion* r = region_at(AOTMetaspace::hp);
1092 
1093     r->init_oopmap(written, mapped_heap_info->oopmap()->size());
1094     written = write_bitmap(mapped_heap_info->oopmap(), buffer, written);
1095 
1096     r->init_ptrmap(written, mapped_heap_info->ptrmap()->size());
1097     written = write_bitmap(mapped_heap_info->ptrmap(), buffer, written);
1098   } else if (streamed_heap_info != nullptr && streamed_heap_info->is_used()) {
1099     assert(HeapShared::is_writing_streaming_mode(), "unexpected dumping mode");
1100     FileMapRegion* r = region_at(AOTMetaspace::hp);
1101 
1102     r->init_oopmap(written, streamed_heap_info->oopmap()->size());
1103     written = write_bitmap(streamed_heap_info->oopmap(), buffer, written);
1104   }
1105 
1106   write_region(AOTMetaspace::bm, (char*)buffer, size_in_bytes, /*read_only=*/true, /*allow_exec=*/false);
1107   return buffer;
1108 }
1109 
1110 #if INCLUDE_CDS_JAVA_HEAP
1111 size_t FileMapInfo::write_mapped_heap_region(AOTMappedHeapInfo* heap_info) {
1112   char* buffer_start = heap_info->buffer_start();
1113   size_t buffer_size = heap_info->buffer_byte_size();
1114   write_region(AOTMetaspace::hp, buffer_start, buffer_size, false, false);
1115   header()->set_mapped_heap_header(heap_info->create_header());
1116   return buffer_size;
1117 }
1118 
1119 size_t FileMapInfo::write_streamed_heap_region(AOTStreamedHeapInfo* heap_info) {
1120   char* buffer_start = heap_info->buffer_start();
1121   size_t buffer_size = heap_info->buffer_byte_size();
1122   write_region(AOTMetaspace::hp, buffer_start, buffer_size, true, false);
1123   header()->set_streamed_heap_header(heap_info->create_header());
1124   return buffer_size;
1125 }
1126 #endif // INCLUDE_CDS_JAVA_HEAP
1127 
1128 // Dump bytes to file -- at the current file position.
1129 
1130 void FileMapInfo::write_bytes(const void* buffer, size_t nbytes) {
1131   assert(_file_open, "must be");
1132   if (!os::write(_fd, buffer, nbytes)) {
1133     // If the shared archive is corrupted, close it and remove it.
1134     close();
1135     remove(_full_path);
1136 
1137     if (CDSConfig::is_dumping_preimage_static_archive()) {
1138       AOTMetaspace::writing_error("Unable to write to AOT configuration file.");
1139     } else if (CDSConfig::new_aot_flags_used()) {
1140       AOTMetaspace::writing_error("Unable to write to AOT cache.");
1141     } else {
1142       AOTMetaspace::writing_error("Unable to write to shared archive.");
1143     }
1144   }
1145   _file_offset += nbytes;
1146 }
1147 
1148 bool FileMapInfo::is_file_position_aligned() const {
1149   return _file_offset == align_up(_file_offset,
1150                                   AOTMetaspace::core_region_alignment());
1151 }
1152 
1153 // Align file position to an allocation unit boundary.
1154 
1155 void FileMapInfo::align_file_position() {
1156   assert(_file_open, "must be");
1157   size_t new_file_offset = align_up(_file_offset,
1158                                     AOTMetaspace::core_region_alignment());
1159   if (new_file_offset != _file_offset) {
1160     _file_offset = new_file_offset;
1161     // Seek one byte back from the target and write a byte to insure
1162     // that the written file is the correct length.
1163     _file_offset -= 1;
1164     seek_to_position(_file_offset);
1165     char zero = 0;
1166     write_bytes(&zero, 1);
1167   }
1168 }
1169 
1170 
1171 // Dump bytes to file -- at the current file position.
1172 
1173 void FileMapInfo::write_bytes_aligned(const void* buffer, size_t nbytes) {
1174   align_file_position();
1175   write_bytes(buffer, nbytes);
1176   align_file_position();
1177 }
1178 
1179 // Close the shared archive file.  This does NOT unmap mapped regions.
1180 
1181 void FileMapInfo::close() {
1182   if (_file_open) {
1183     if (::close(_fd) < 0) {
1184       AOTMetaspace::unrecoverable_loading_error("Unable to close the shared archive file.");
1185     }
1186     _file_open = false;
1187     _fd = -1;
1188   }
1189 }
1190 
1191 /*
1192  * Same as os::map_memory() but also pretouches if AlwaysPreTouch is enabled.
1193  */
1194 static char* map_memory(int fd, const char* file_name, size_t file_offset,
1195                         char* addr, size_t bytes, bool read_only,
1196                         bool allow_exec, MemTag mem_tag) {
1197   char* mem = os::map_memory(fd, file_name, file_offset, addr, bytes,
1198                              mem_tag, AlwaysPreTouch ? false : read_only,
1199                              allow_exec);
1200   if (mem != nullptr && AlwaysPreTouch) {
1201     os::pretouch_memory(mem, mem + bytes);
1202   }
1203   return mem;
1204 }
1205 
1206 char* FileMapInfo::map_heap_region(FileMapRegion* r, char* addr, size_t bytes) {
1207   return ::map_memory(_fd,
1208                     _full_path,
1209                     r->file_offset(),
1210                     addr,
1211                     bytes,
1212                     r->read_only(),
1213                     r->allow_exec(),
1214                     mtJavaHeap);
1215 }
1216 
1217 // JVM/TI RedefineClasses() support:
1218 // Remap the shared readonly space to shared readwrite, private.
1219 bool FileMapInfo::remap_shared_readonly_as_readwrite() {
1220   int idx = AOTMetaspace::ro;
1221   FileMapRegion* r = region_at(idx);
1222   if (!r->read_only()) {
1223     // the space is already readwrite so we are done
1224     return true;
1225   }
1226   size_t size = r->used_aligned();
1227   if (!open_for_read()) {
1228     return false;
1229   }
1230   char *addr = r->mapped_base();
1231   // This path should not be reached for Windows; see JDK-8222379.
1232   assert(WINDOWS_ONLY(false) NOT_WINDOWS(true), "Don't call on Windows");
1233   // Replace old mapping with new one that is writable.
1234   char *base = os::map_memory(_fd, _full_path, r->file_offset(),
1235                               addr, size, mtNone, false /* !read_only */,
1236                               r->allow_exec());
1237   close();
1238   // These have to be errors because the shared region is now unmapped.
1239   if (base == nullptr) {
1240     aot_log_error(aot)("Unable to remap shared readonly space (errno=%d).", errno);
1241     vm_exit(1);
1242   }
1243   if (base != addr) {
1244     aot_log_error(aot)("Unable to remap shared readonly space (errno=%d).", errno);
1245     vm_exit(1);
1246   }
1247   r->set_read_only(false);
1248   return true;
1249 }
1250 
1251 // Memory map a region in the address space.
1252 static const char* shared_region_name[] = { "ReadWrite", "ReadOnly", "Bitmap", "Heap", "Code" };
1253 
1254 MapArchiveResult FileMapInfo::map_regions(int regions[], int num_regions, char* mapped_base_address, ReservedSpace rs) {
1255   DEBUG_ONLY(FileMapRegion* last_region = nullptr);
1256   intx addr_delta = mapped_base_address - header()->requested_base_address();
1257 
1258   // Make sure we don't attempt to use header()->mapped_base_address() unless
1259   // it's been successfully mapped.
1260   DEBUG_ONLY(header()->set_mapped_base_address((char*)(uintptr_t)0xdeadbeef);)
1261 
1262   for (int i = 0; i < num_regions; i++) {
1263     int idx = regions[i];
1264     MapArchiveResult result = map_region(idx, addr_delta, mapped_base_address, rs);
1265     if (result != MAP_ARCHIVE_SUCCESS) {
1266       return result;
1267     }
1268     FileMapRegion* r = region_at(idx);
1269     DEBUG_ONLY(if (last_region != nullptr) {
1270         // Ensure that the OS won't be able to allocate new memory spaces between any mapped
1271         // regions, or else it would mess up the simple comparison in MetaspaceObj::in_aot_cache().
1272         assert(r->mapped_base() == last_region->mapped_end(), "must have no gaps");
1273       }
1274       last_region = r;)
1275     aot_log_info(aot)("Mapped %s region #%d at base " INTPTR_FORMAT " top " INTPTR_FORMAT " (%s)", is_static() ? "static " : "dynamic",
1276                   idx, p2i(r->mapped_base()), p2i(r->mapped_end()),
1277                   shared_region_name[idx]);
1278 
1279   }
1280 
1281   header()->set_mapped_base_address(header()->requested_base_address() + addr_delta);
1282   if (addr_delta != 0 && !relocate_pointers_in_core_regions(addr_delta)) {
1283     return MAP_ARCHIVE_OTHER_FAILURE;
1284   }
1285 
1286   return MAP_ARCHIVE_SUCCESS;
1287 }
1288 
1289 bool FileMapInfo::read_region(int i, char* base, size_t size, bool do_commit) {
1290   FileMapRegion* r = region_at(i);
1291   if (do_commit) {
1292     aot_log_info(aot)("Commit %s region #%d at base " INTPTR_FORMAT " top " INTPTR_FORMAT " (%s)%s",
1293                   is_static() ? "static " : "dynamic", i, p2i(base), p2i(base + size),
1294                   shared_region_name[i], r->allow_exec() ? " exec" : "");
1295     if (!os::commit_memory(base, size, r->allow_exec())) {
1296       aot_log_error(aot)("Failed to commit %s region #%d (%s)", is_static() ? "static " : "dynamic",
1297                      i, shared_region_name[i]);
1298       return false;
1299     }
1300   }
1301   if (os::lseek(_fd, (long)r->file_offset(), SEEK_SET) != (int)r->file_offset() ||
1302       read_bytes(base, size) != size) {
1303     return false;
1304   }
1305 
1306   if (VerifySharedSpaces && !r->check_region_crc(base)) {
1307     return false;
1308   }
1309 
1310   r->set_mapped_from_file(false);
1311   r->set_mapped_base(base);
1312 
1313   return true;
1314 }
1315 
1316 MapArchiveResult FileMapInfo::map_region(int i, intx addr_delta, char* mapped_base_address, ReservedSpace rs) {
1317   assert(!HeapShared::is_heap_region(i), "sanity");
1318   FileMapRegion* r = region_at(i);
1319   size_t size = r->used_aligned();
1320   char *requested_addr = mapped_base_address + r->mapping_offset();
1321   assert(!is_mapped(), "must be not mapped yet");
1322   assert(requested_addr != nullptr, "must be specified");
1323 
1324   r->set_mapped_from_file(false);
1325   r->set_in_reserved_space(false);
1326 
1327   if (AOTMetaspace::use_windows_memory_mapping()) {
1328     // Windows cannot remap read-only shared memory to read-write when required for
1329     // RedefineClasses, which is also used by JFR.  Always map windows regions as RW.
1330     r->set_read_only(false);
1331   } else if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space() ||
1332              Arguments::has_jfr_option()) {
1333     // If a tool agent is in use (debugging enabled), or JFR, we must map the address space RW
1334     r->set_read_only(false);
1335   } else if (addr_delta != 0) {
1336     r->set_read_only(false); // Need to patch the pointers
1337   }
1338 
1339   if (AOTMetaspace::use_windows_memory_mapping() && rs.is_reserved()) {
1340     // This is the second time we try to map the archive(s). We have already created a ReservedSpace
1341     // that covers all the FileMapRegions to ensure all regions can be mapped. However, Windows
1342     // can't mmap into a ReservedSpace, so we just ::read() the data. We're going to patch all the
1343     // regions anyway, so there's no benefit for mmap anyway.
1344     if (!read_region(i, requested_addr, size, /* do_commit = */ true)) {
1345       AOTMetaspace::report_loading_error("Failed to read %s shared space into reserved space at " INTPTR_FORMAT,
1346                                             shared_region_name[i], p2i(requested_addr));
1347       return MAP_ARCHIVE_OTHER_FAILURE; // oom or I/O error.
1348     } else {
1349       assert(r->mapped_base() != nullptr, "must be initialized");
1350     }
1351   } else {
1352     // Note that this may either be a "fresh" mapping into unreserved address
1353     // space (Windows, first mapping attempt), or a mapping into pre-reserved
1354     // space (Posix). See also comment in AOTMetaspace::map_archives().
1355     char* base = map_memory(_fd, _full_path, r->file_offset(),
1356                             requested_addr, size, r->read_only(),
1357                             r->allow_exec(), mtClassShared);
1358     if (base != requested_addr) {
1359       AOTMetaspace::report_loading_error("Unable to map %s shared space at " INTPTR_FORMAT,
1360                                             shared_region_name[i], p2i(requested_addr));
1361       _memory_mapping_failed = true;
1362       return MAP_ARCHIVE_MMAP_FAILURE;
1363     }
1364 
1365     if (VerifySharedSpaces && !r->check_region_crc(requested_addr)) {
1366       return MAP_ARCHIVE_OTHER_FAILURE;
1367     }
1368 
1369     r->set_mapped_from_file(true);
1370     r->set_mapped_base(requested_addr);
1371   }
1372 
1373   if (rs.is_reserved()) {
1374     char* mapped_base = r->mapped_base();
1375     assert(rs.base() <= mapped_base && mapped_base + size <= rs.end(),
1376            PTR_FORMAT " <= " PTR_FORMAT " < " PTR_FORMAT " <= " PTR_FORMAT,
1377            p2i(rs.base()), p2i(mapped_base), p2i(mapped_base + size), p2i(rs.end()));
1378     r->set_in_reserved_space(rs.is_reserved());
1379   }
1380   return MAP_ARCHIVE_SUCCESS;
1381 }
1382 
1383 // The return value is the location of the archive relocation bitmap.
1384 char* FileMapInfo::map_auxiliary_region(int region_index, bool read_only) {
1385   FileMapRegion* r = region_at(region_index);
1386   if (r->mapped_base() != nullptr) {
1387     return r->mapped_base();
1388   }
1389   const char* region_name = shared_region_name[region_index];
1390   bool allow_exec = false;
1391   char* requested_addr = nullptr; // allow OS to pick any location
1392   char* mapped_base = map_memory(_fd, _full_path, r->file_offset(),
1393                                  requested_addr, r->used_aligned(), read_only, allow_exec, mtClassShared);
1394   if (mapped_base == nullptr) {
1395     AOTMetaspace::report_loading_error("failed to map %d region", region_index);
1396     return nullptr;
1397   }
1398 
1399   if (VerifySharedSpaces && !r->check_region_crc(mapped_base)) {
1400     aot_log_error(aot)("region %d CRC error", region_index);
1401     os::unmap_memory(mapped_base, r->used_aligned());
1402     return nullptr;
1403   }
1404 
1405   r->set_mapped_from_file(true);
1406   r->set_mapped_base(mapped_base);
1407   aot_log_info(aot)("Mapped %s region #%d at base %zu top %zu (%s)",
1408                 is_static() ? "static " : "dynamic",
1409                 region_index, p2i(r->mapped_base()), p2i(r->mapped_end()),
1410                 region_name);
1411   return mapped_base;
1412 }
1413 
1414 char* FileMapInfo::map_bitmap_region() {
1415   return map_auxiliary_region(AOTMetaspace::bm, false);
1416 }
1417 
1418 bool FileMapInfo::map_aot_code_region(ReservedSpace rs) {
1419   FileMapRegion* r = region_at(AOTMetaspace::ac);
1420   assert(r->used() > 0 && r->used_aligned() == rs.size(), "must be");
1421 
1422   if (UseCompressedOops) {
1423     precond(header()->compatible_oop_compression() == AOTCompatibleOopCompression);
1424   }
1425 
1426   char* requested_base = rs.base();
1427   assert(requested_base != nullptr, "should be inside code cache");
1428 
1429   char* mapped_base;
1430   if (AOTMetaspace::use_windows_memory_mapping()) {
1431     if (!read_region(AOTMetaspace::ac, requested_base, r->used_aligned(), /* do_commit = */ true)) {
1432       AOTMetaspace::report_loading_error("Failed to read aot code shared space into reserved space at " INTPTR_FORMAT,
1433                                             p2i(requested_base));
1434       return false;
1435     }
1436     mapped_base = requested_base;
1437   } else {
1438     // We do not execute in-place in the AOT code region.
1439     // AOT code is copied to the CodeCache for execution.
1440     bool read_only = false, allow_exec = false;
1441     mapped_base = map_memory(_fd, _full_path, r->file_offset(),
1442                              requested_base, r->used_aligned(), read_only, allow_exec, mtClassShared);
1443   }
1444   if (mapped_base == nullptr) {
1445     AOTMetaspace::report_loading_error("failed to map aot code region");
1446     return false;
1447   } else {
1448     assert(mapped_base == requested_base, "must be");
1449 
1450     if (VerifySharedSpaces && !r->check_region_crc(mapped_base)) {
1451       aot_log_error(aot)("region %d CRC error", AOTMetaspace::ac);
1452       os::unmap_memory(mapped_base, r->used_aligned());
1453       return false;
1454     }
1455 
1456     r->set_mapped_from_file(true);
1457     r->set_mapped_base(mapped_base);
1458     aot_log_info(aot)("Mapped static  region #%d at base " INTPTR_FORMAT " top " INTPTR_FORMAT " (%s)",
1459                   AOTMetaspace::ac, p2i(r->mapped_base()), p2i(r->mapped_end()),
1460                   shared_region_name[AOTMetaspace::ac]);
1461     return true;
1462   }
1463 }
1464 
1465 class SharedDataRelocationTask : public ArchiveWorkerTask {
1466 private:
1467   BitMapView* const _rw_bm;
1468   BitMapView* const _ro_bm;
1469   SharedDataRelocator* const _rw_reloc;
1470   SharedDataRelocator* const _ro_reloc;
1471 
1472 public:
1473   SharedDataRelocationTask(BitMapView* rw_bm, BitMapView* ro_bm, SharedDataRelocator* rw_reloc, SharedDataRelocator* ro_reloc) :
1474                            ArchiveWorkerTask("Shared Data Relocation"),
1475                            _rw_bm(rw_bm), _ro_bm(ro_bm), _rw_reloc(rw_reloc), _ro_reloc(ro_reloc) {}
1476 
1477   void work(int chunk, int max_chunks) override {
1478     work_on(chunk, max_chunks, _rw_bm, _rw_reloc);
1479     work_on(chunk, max_chunks, _ro_bm, _ro_reloc);
1480   }
1481 
1482   void work_on(int chunk, int max_chunks, BitMapView* bm, SharedDataRelocator* reloc) {
1483     BitMap::idx_t size  = bm->size();
1484     BitMap::idx_t start = MIN2(size, size * chunk / max_chunks);
1485     BitMap::idx_t end   = MIN2(size, size * (chunk + 1) / max_chunks);
1486     assert(end > start, "Sanity: no empty slices");
1487     bm->iterate(reloc, start, end);
1488   }
1489 };
1490 
1491 // This is called when we cannot map the archive at the requested[ base address (usually 0x800000000).
1492 // We relocate all pointers in the 2 core regions (ro, rw).
1493 bool FileMapInfo::relocate_pointers_in_core_regions(intx addr_delta) {
1494   aot_log_debug(aot, reloc)("runtime archive relocation start");
1495   char* bitmap_base = map_bitmap_region();
1496 
1497   if (bitmap_base == nullptr) {
1498     return false; // OOM, or CRC check failure
1499   } else {
1500     BitMapView rw_ptrmap = ptrmap_view(AOTMetaspace::rw);
1501     BitMapView ro_ptrmap = ptrmap_view(AOTMetaspace::ro);
1502 
1503     FileMapRegion* rw_region = first_core_region();
1504     FileMapRegion* ro_region = last_core_region();
1505 
1506     // Patch all pointers inside the RW region
1507     address rw_patch_base = (address)rw_region->mapped_base();
1508     address rw_patch_end  = (address)rw_region->mapped_end();
1509 
1510     // Patch all pointers inside the RO region
1511     address ro_patch_base = (address)ro_region->mapped_base();
1512     address ro_patch_end  = (address)ro_region->mapped_end();
1513 
1514     // the current value of the pointers to be patched must be within this
1515     // range (i.e., must be between the requested base address and the address of the current archive).
1516     // Note: top archive may point to objects in the base archive, but not the other way around.
1517     address valid_old_base = (address)header()->requested_base_address();
1518     address valid_old_end  = valid_old_base + mapping_end_offset();
1519 
1520     // after patching, the pointers must point inside this range
1521     // (the requested location of the archive, as mapped at runtime).
1522     address valid_new_base = (address)header()->mapped_base_address();
1523     address valid_new_end  = (address)mapped_end();
1524 
1525     SharedDataRelocator rw_patcher((address*)rw_patch_base + header()->rw_ptrmap_start_pos(), (address*)rw_patch_end, valid_old_base, valid_old_end,
1526                                 valid_new_base, valid_new_end, addr_delta);
1527     SharedDataRelocator ro_patcher((address*)ro_patch_base + header()->ro_ptrmap_start_pos(), (address*)ro_patch_end, valid_old_base, valid_old_end,
1528                                 valid_new_base, valid_new_end, addr_delta);
1529 
1530     if (AOTCacheParallelRelocation) {
1531       ArchiveWorkers workers;
1532       SharedDataRelocationTask task(&rw_ptrmap, &ro_ptrmap, &rw_patcher, &ro_patcher);
1533       workers.run_task(&task);
1534     } else {
1535       rw_ptrmap.iterate(&rw_patcher);
1536       ro_ptrmap.iterate(&ro_patcher);
1537     }
1538 
1539     // The AOTMetaspace::bm region will be unmapped in AOTMetaspace::initialize_shared_spaces().
1540 
1541     aot_log_debug(aot, reloc)("runtime archive relocation done");
1542     return true;
1543   }
1544 }
1545 
1546 size_t FileMapInfo::read_bytes(void* buffer, size_t count) {
1547   assert(_file_open, "Archive file is not open");
1548   size_t n = ::read(_fd, buffer, (unsigned int)count);
1549   if (n != count) {
1550     // Close the file if there's a problem reading it.
1551     close();
1552     return 0;
1553   }
1554   _file_offset += count;
1555   return count;
1556 }
1557 
1558 // Get the total size in bytes of all mapped read only region
1559 size_t FileMapInfo::readonly_total() {
1560   size_t total = 0;
1561   if (current_info() != nullptr && current_info()->is_mapped()) {
1562     FileMapRegion* r = FileMapInfo::current_info()->region_at(AOTMetaspace::ro);
1563     if (r->read_only()) total += r->used();
1564   }
1565   if (dynamic_info() != nullptr && current_info()->is_mapped()) {
1566     FileMapRegion* r = FileMapInfo::dynamic_info()->region_at(AOTMetaspace::ro);
1567     if (r->read_only()) total += r->used();
1568   }
1569   return total;
1570 }
1571 
1572 #if INCLUDE_CDS_JAVA_HEAP
1573 
1574 bool FileMapInfo::has_heap_region() {
1575   return (region_at(AOTMetaspace::hp)->used() > 0);
1576 }
1577 
1578 static void on_heap_region_loading_error() {
1579   if (CDSConfig::is_using_aot_linked_classes()) {
1580     // It's too late to recover -- we have already committed to use the archived metaspace objects, but
1581     // the archived heap objects cannot be loaded, so we don't have the archived FMG to guarantee that
1582     // all AOT-linked classes are visible.
1583     //
1584     // We get here because the heap is too small. The app will fail anyway. So let's quit.
1585     aot_log_error(aot)("%s has aot-linked classes but the archived "
1586                        "heap objects cannot be loaded. Try increasing your heap size.",
1587                        CDSConfig::type_of_archive_being_loaded());
1588     AOTMetaspace::unrecoverable_loading_error();
1589   }
1590   CDSConfig::stop_using_full_module_graph();
1591 }
1592 
1593 void FileMapInfo::stream_heap_region() {
1594   assert(object_streaming_mode(), "This should only be done for the streaming approach");
1595 
1596   if (map_auxiliary_region(AOTMetaspace::hp, /*readonly=*/true) != nullptr) {
1597     HeapShared::initialize_streaming();
1598   } else {
1599     on_heap_region_loading_error();
1600   }
1601 }
1602 
1603 void FileMapInfo::map_or_load_heap_region() {
1604   assert(!object_streaming_mode(), "This should only be done for the mapping approach");
1605   bool success = false;
1606 
1607   if (AOTMappedHeapLoader::can_map()) {
1608     success = AOTMappedHeapLoader::map_heap_region(this);
1609   } else if (AOTMappedHeapLoader::can_load()) {
1610     success = AOTMappedHeapLoader::load_heap_region(this);
1611   }
1612 
1613   if (!success) {
1614     on_heap_region_loading_error();
1615   }
1616 }
1617 
1618 bool FileMapInfo::can_use_heap_region() {
1619   if (!has_heap_region()) {
1620     return false;
1621   }
1622 
1623   if (!object_streaming_mode() && !AOTMappedHeapLoader::can_use()) {
1624     // Currently this happens only when using ZGC with an AOT cache generated with -XX:-AOTStreamableObjects
1625     AOTMetaspace::report_loading_error("CDS heap data cannot be used by the selected GC. "
1626                                        "Please choose a different GC or rebuild AOT cache "
1627                                        "with -XX:+AOTStreamableObjects");
1628     return false;
1629   }
1630 
1631   if (CDSConfig::is_using_aot_linked_classes()) {
1632     assert(!JvmtiExport::should_post_class_file_load_hook(), "already checked");
1633     assert(CDSConfig::is_using_full_module_graph(), "already checked");
1634   } else {
1635     if (JvmtiExport::should_post_class_file_load_hook()) {
1636       AOTMetaspace::report_loading_error("CDS heap data is disabled because JVMTI ClassFileLoadHook is in use.");
1637       return false;
1638     }
1639     if (!CDSConfig::is_using_full_module_graph()) {
1640       if (CDSConfig::is_dumping_final_static_archive()) {
1641         // We are loading the preimage static archive, which has no KlassSubGraphs.
1642         // See CDSConfig::is_dumping_klass_subgraphs()
1643       } else {
1644         AOTMetaspace::report_loading_error("CDS heap data is disabled because archived full module graph is not used.");
1645         return false;
1646       }
1647     }
1648   }
1649 
1650   if (JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()) {
1651     ShouldNotReachHere(); // CDS should have been disabled.
1652     // The archived objects are mapped at JVM start-up, but we don't know if
1653     // j.l.String or j.l.Class might be replaced by the ClassFileLoadHook,
1654     // which would make the archived String or mirror objects invalid. Let's be safe and not
1655     // use the archived objects. These 2 classes are loaded during the JVMTI "early" stage.
1656     //
1657     // If JvmtiExport::has_early_class_hook_env() is false, the classes of some objects
1658     // in the archived subgraphs may be replaced by the ClassFileLoadHook. But that's OK
1659     // because we won't install an archived object subgraph if the klass of any of the
1660     // referenced objects are replaced. See HeapShared::initialize_from_archived_subgraph().
1661   }
1662 
1663   // We pre-compute narrow Klass IDs with the runtime mapping start intended to be the base, and a shift of
1664   // HeapShared::precomputed_narrow_klass_shift. We enforce this encoding at runtime (see
1665   // CompressedKlassPointers::initialize_for_given_encoding()). Therefore, the following assertions must
1666   // hold:
1667   address archive_narrow_klass_base = (address)header()->mapped_base_address();
1668   const int archive_narrow_klass_pointer_bits = header()->narrow_klass_pointer_bits();
1669   const int archive_narrow_klass_shift = header()->narrow_klass_shift();
1670 
1671   aot_log_info(aot)("CDS archive was created with max heap size = %zuM, and the following configuration:",
1672                 max_heap_size()/M);
1673 
1674   aot_log_info(aot)("    narrow_klass_base at mapping start address, narrow_klass_pointer_bits = %d, narrow_klass_shift = %d",
1675                 archive_narrow_klass_pointer_bits, archive_narrow_klass_shift);
1676   if (UseCompressedOops) {
1677     aot_log_info(aot)("    narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d",
1678                       narrow_oop_mode(), p2i(narrow_oop_base()), narrow_oop_shift());
1679     aot_log_info(aot)("    AOTCompatibleOopCompression = %s", header()->compatible_oop_compression() ? "true" : "false");
1680   }
1681   aot_log_info(aot)("The current max heap size = %zuM, G1HeapRegion::GrainBytes = %zu",
1682                 MaxHeapSize/M, G1HeapRegion::GrainBytes);
1683   aot_log_info(aot)("    narrow_klass_base = " PTR_FORMAT ", arrow_klass_pointer_bits = %d, narrow_klass_shift = %d",
1684                 p2i(CompressedKlassPointers::base()), CompressedKlassPointers::narrow_klass_pointer_bits(), CompressedKlassPointers::shift());
1685   if (UseCompressedOops) {
1686     aot_log_info(aot)("    narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d",
1687                       CompressedOops::mode(), p2i(CompressedOops::base()), CompressedOops::shift());
1688     aot_log_info(aot)("    AOTCompatibleOopCompression = %s", AOTCompatibleOopCompression ? "true" : "false");
1689   }
1690   if (!object_streaming_mode()) {
1691     aot_log_info(aot)("    heap range = [" PTR_FORMAT " - "  PTR_FORMAT "]",
1692                       UseCompressedOops ? p2i(CompressedOops::begin()) :
1693                       UseG1GC ? p2i((address)G1CollectedHeap::heap()->reserved().start()) : 0L,
1694                       UseCompressedOops ? p2i(CompressedOops::end()) :
1695                       UseG1GC ? p2i((address)G1CollectedHeap::heap()->reserved().end()) : 0L);
1696   }
1697 
1698   int err = 0;
1699   if ( archive_narrow_klass_base != CompressedKlassPointers::base() ||
1700        (err = 1, archive_narrow_klass_pointer_bits != CompressedKlassPointers::narrow_klass_pointer_bits()) ||
1701        (err = 2, archive_narrow_klass_shift != CompressedKlassPointers::shift()) ) {
1702     stringStream ss;
1703     switch (err) {
1704     case 0:
1705       ss.print("Unexpected encoding base encountered (" PTR_FORMAT ", expected " PTR_FORMAT ")",
1706                p2i(CompressedKlassPointers::base()), p2i(archive_narrow_klass_base));
1707       break;
1708     case 1:
1709       ss.print("Unexpected narrow Klass bit length encountered (%d, expected %d)",
1710                CompressedKlassPointers::narrow_klass_pointer_bits(), archive_narrow_klass_pointer_bits);
1711       break;
1712     case 2:
1713       ss.print("Unexpected narrow Klass shift encountered (%d, expected %d)",
1714                CompressedKlassPointers::shift(), archive_narrow_klass_shift);
1715       break;
1716     default:
1717       ShouldNotReachHere();
1718     };
1719     if (CDSConfig::new_aot_flags_used()) {
1720       LogTarget(Info, aot) lt;
1721       if (lt.is_enabled()) {
1722         LogStream ls(lt);
1723         ls.print_raw(ss.base());
1724         header()->print(&ls);
1725       }
1726     } else {
1727       LogTarget(Info, cds) lt;
1728       if (lt.is_enabled()) {
1729         LogStream ls(lt);
1730         ls.print_raw(ss.base());
1731         header()->print(&ls);
1732       }
1733     }
1734     assert(false, "%s", ss.base());
1735   }
1736 
1737   return true;
1738 }
1739 
1740 #endif // INCLUDE_CDS_JAVA_HEAP
1741 
1742 // Unmap a memory region in the address space.
1743 
1744 void FileMapInfo::unmap_regions(int regions[], int num_regions) {
1745   for (int r = 0; r < num_regions; r++) {
1746     int idx = regions[r];
1747     unmap_region(idx);
1748   }
1749 }
1750 
1751 void FileMapInfo::unmap_region(int i) {
1752   FileMapRegion* r = region_at(i);
1753   char* mapped_base = r->mapped_base();
1754   size_t size = r->used_aligned();
1755 
1756   if (mapped_base != nullptr) {
1757     if (size > 0 && r->mapped_from_file()) {
1758       aot_log_info(aot)("Unmapping region #%d at base " INTPTR_FORMAT " (%s)", i, p2i(mapped_base),
1759                     shared_region_name[i]);
1760       if (r->in_reserved_space()) {
1761         // This region was mapped inside a ReservedSpace. Its memory will be freed when the ReservedSpace
1762         // is released. Zero it so that we don't accidentally read its content.
1763         aot_log_info(aot)("Region #%d (%s) is in a reserved space, it will be freed when the space is released", i, shared_region_name[i]);
1764       } else {
1765         os::unmap_memory(mapped_base, size);
1766       }
1767     }
1768     r->set_mapped_base(nullptr);
1769   }
1770 }
1771 
1772 void FileMapInfo::assert_mark(bool check) {
1773   if (!check) {
1774     AOTMetaspace::unrecoverable_loading_error("Mark mismatch while restoring from shared file.");
1775   }
1776 }
1777 
1778 FileMapInfo* FileMapInfo::_current_info = nullptr;
1779 FileMapInfo* FileMapInfo::_dynamic_archive_info = nullptr;
1780 bool FileMapInfo::_memory_mapping_failed = false;
1781 
1782 // Open the shared archive file, read and validate the header
1783 // information (version, boot classpath, etc.). If initialization
1784 // fails, shared spaces are disabled and the file is closed.
1785 //
1786 // Validation of the archive is done in two steps:
1787 //
1788 // [1] validate_header() - done here.
1789 // [2] validate_shared_path_table - this is done later, because the table is in the RO
1790 //     region of the archive, which is not mapped yet.
1791 bool FileMapInfo::open_as_input() {
1792   assert(CDSConfig::is_using_archive(), "UseSharedSpaces expected.");
1793   assert(Arguments::has_jimage(), "The shared archive file cannot be used with an exploded module build.");
1794 
1795   if (JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()) {
1796     // CDS assumes that no classes resolved in vmClasses::resolve_all()
1797     // are replaced at runtime by JVMTI ClassFileLoadHook. All of those classes are resolved
1798     // during the JVMTI "early" stage, so we can still use CDS if
1799     // JvmtiExport::has_early_class_hook_env() is false.
1800     AOTMetaspace::report_loading_error("CDS is disabled because early JVMTI ClassFileLoadHook is in use.");
1801     return false;
1802   }
1803 
1804   if (!open_for_read() || !init_from_file(_fd) || !validate_header()) {
1805     if (_is_static) {
1806       AOTMetaspace::report_loading_error("Loading static archive failed.");
1807       return false;
1808     } else {
1809       AOTMetaspace::report_loading_error("Loading dynamic archive failed.");
1810       if (AutoCreateSharedArchive) {
1811         CDSConfig::enable_dumping_dynamic_archive(_full_path);
1812       }
1813       return false;
1814     }
1815   }
1816 
1817   return true;
1818 }
1819 
1820 bool FileMapInfo::validate_aot_class_linking() {
1821   // These checks need to be done after FileMapInfo::initialize(), which gets called before Universe::heap()
1822   // is available.
1823   if (header()->has_aot_linked_classes()) {
1824     const char* archive_type = CDSConfig::type_of_archive_being_loaded();
1825     CDSConfig::set_has_aot_linked_classes(true);
1826     if (JvmtiExport::should_post_class_file_load_hook()) {
1827       aot_log_error(aot)("%s has aot-linked classes. It cannot be used when JVMTI ClassFileLoadHook is in use.",
1828                      archive_type);
1829       return false;
1830     }
1831     if (JvmtiExport::has_early_vmstart_env()) {
1832       aot_log_error(aot)("%s has aot-linked classes. It cannot be used when JVMTI early vm start is in use.",
1833                      archive_type);
1834       return false;
1835     }
1836     if (!CDSConfig::is_using_full_module_graph()) {
1837       aot_log_error(aot)("%s has aot-linked classes. It cannot be used when archived full module graph is not used.",
1838                      archive_type);
1839       return false;
1840     }
1841 
1842     const char* prop = Arguments::get_property("java.security.manager");
1843     if (prop != nullptr && strcmp(prop, "disallow") != 0) {
1844       aot_log_error(aot)("%s has aot-linked classes. It cannot be used with -Djava.security.manager=%s.",
1845                      archive_type, prop);
1846       return false;
1847     }
1848 
1849 #if INCLUDE_JVMTI
1850     if (Arguments::has_jdwp_agent()) {
1851       aot_log_error(aot)("%s has aot-linked classes. It cannot be used with JDWP agent", archive_type);
1852       return false;
1853     }
1854 #endif
1855   }
1856 
1857   return true;
1858 }
1859 
1860 // The 2 core spaces are RW->RO
1861 FileMapRegion* FileMapInfo::first_core_region() const {
1862   return region_at(AOTMetaspace::rw);
1863 }
1864 
1865 FileMapRegion* FileMapInfo::last_core_region() const {
1866   return region_at(AOTMetaspace::ro);
1867 }
1868 
1869 void FileMapInfo::print(outputStream* st) const {
1870   header()->print(st);
1871   if (!is_static()) {
1872     dynamic_header()->print(st);
1873   }
1874 }
1875 
1876 int FileMapHeader::compute_crc() {
1877   char* start = (char*)this;
1878   // start computing from the field after _header_size to end of base archive name.
1879   char* buf = (char*)&(_generic_header._header_size) + sizeof(_generic_header._header_size);
1880   size_t sz = header_size() - (buf - start);
1881   int crc = ClassLoader::crc32(0, buf, (jint)sz);
1882   return crc;
1883 }
1884 
1885 // This function should only be called during run time with UseSharedSpaces enabled.
1886 bool FileMapHeader::validate() {
1887   const char* file_type = CDSConfig::type_of_archive_being_loaded();
1888   if (_obj_alignment != ObjectAlignmentInBytes) {
1889     AOTMetaspace::report_loading_error("The %s's ObjectAlignmentInBytes of %d"
1890                                           " does not equal the current ObjectAlignmentInBytes of %d.",
1891                                           file_type, _obj_alignment, ObjectAlignmentInBytes);
1892     return false;
1893   }
1894   if (_compact_strings != CompactStrings) {
1895     AOTMetaspace::report_loading_error("The %s's CompactStrings setting (%s)"
1896                                           " does not equal the current CompactStrings setting (%s).", file_type,
1897                                           _compact_strings ? "enabled" : "disabled",
1898                                           CompactStrings   ? "enabled" : "disabled");
1899     return false;
1900   }
1901   bool jvmci_compiler_is_enabled = CompilerConfig::is_jvmci_compiler_enabled();
1902   CompilerType compiler_type = CompilerConfig::compiler_type();
1903   CompilerType archive_compiler_type = CompilerType(_compiler_type);
1904   // JVMCI compiler does different type profiling settigns and generate
1905   // different code. We can't use archive which was produced
1906   // without it and reverse.
1907   // Only allow mix when JIT compilation is disabled.
1908   // Interpreter is used by default when dumping archive.
1909   bool intepreter_is_used = (archive_compiler_type == CompilerType::compiler_none) ||
1910                             (compiler_type == CompilerType::compiler_none);
1911   if (!intepreter_is_used &&
1912       jvmci_compiler_is_enabled != (archive_compiler_type == CompilerType::compiler_jvmci)) {
1913     AOTMetaspace::report_loading_error("The %s's JIT compiler setting (%s)"
1914                                           " does not equal the current setting (%s).", file_type,
1915                                           compilertype2name(archive_compiler_type), compilertype2name(compiler_type));
1916     return false;
1917   }
1918   if (TrainingData::have_data()) {
1919     if (_type_profile_level != TypeProfileLevel) {
1920       AOTMetaspace::report_loading_error("The %s's TypeProfileLevel setting (%d)"
1921                                             " does not equal the current TypeProfileLevel setting (%d).", file_type,
1922                                             _type_profile_level, TypeProfileLevel);
1923       return false;
1924     }
1925     if (_type_profile_args_limit != TypeProfileArgsLimit) {
1926       AOTMetaspace::report_loading_error("The %s's TypeProfileArgsLimit setting (%d)"
1927                                             " does not equal the current TypeProfileArgsLimit setting (%d).", file_type,
1928                                             _type_profile_args_limit, TypeProfileArgsLimit);
1929       return false;
1930     }
1931     if (_type_profile_parms_limit != TypeProfileParmsLimit) {
1932       AOTMetaspace::report_loading_error("The %s's TypeProfileParamsLimit setting (%d)"
1933                                             " does not equal the current TypeProfileParamsLimit setting (%d).", file_type,
1934                                             _type_profile_args_limit, TypeProfileArgsLimit);
1935       return false;
1936 
1937     }
1938     if (_type_profile_width != TypeProfileWidth) {
1939       AOTMetaspace::report_loading_error("The %s's TypeProfileWidth setting (%d)"
1940                                             " does not equal the current TypeProfileWidth setting (%d).", file_type,
1941                                             (int)_type_profile_width, (int)TypeProfileWidth);
1942       return false;
1943 
1944     }
1945     if (_bci_profile_width != BciProfileWidth) {
1946       AOTMetaspace::report_loading_error("The %s's BciProfileWidth setting (%d)"
1947                                             " does not equal the current BciProfileWidth setting (%d).", file_type,
1948                                             (int)_bci_profile_width, (int)BciProfileWidth);
1949       return false;
1950     }
1951     if (_type_profile_casts != TypeProfileCasts) {
1952       AOTMetaspace::report_loading_error("The %s's TypeProfileCasts setting (%s)"
1953                                             " does not equal the current TypeProfileCasts setting (%s).", file_type,
1954                                             _type_profile_casts ? "enabled" : "disabled",
1955                                             TypeProfileCasts    ? "enabled" : "disabled");
1956 
1957       return false;
1958 
1959     }
1960     if (_profile_traps != ProfileTraps) {
1961       AOTMetaspace::report_loading_error("The %s's ProfileTraps setting (%s)"
1962                                             " does not equal the current ProfileTraps setting (%s).", file_type,
1963                                             _profile_traps ? "enabled" : "disabled",
1964                                             ProfileTraps   ? "enabled" : "disabled");
1965 
1966       return false;
1967     }
1968     if (_spec_trap_limit_extra_entries != SpecTrapLimitExtraEntries) {
1969       AOTMetaspace::report_loading_error("The %s's SpecTrapLimitExtraEntries setting (%d)"
1970                                             " does not equal the current SpecTrapLimitExtraEntries setting (%d).", file_type,
1971                                             _spec_trap_limit_extra_entries, SpecTrapLimitExtraEntries);
1972       return false;
1973 
1974     }
1975   }
1976 
1977   // This must be done after header validation because it might change the
1978   // header data
1979   const char* prop = Arguments::get_property("java.system.class.loader");
1980   if (prop != nullptr) {
1981     if (has_aot_linked_classes()) {
1982       AOTMetaspace::report_loading_error("%s has aot-linked classes. It cannot be used when the "
1983                                             "java.system.class.loader property is specified.",
1984                                             CDSConfig::type_of_archive_being_loaded());
1985       return false;
1986     }
1987     aot_log_warning(aot)("Archived non-system classes are disabled because the "
1988             "java.system.class.loader property is specified (value = \"%s\"). "
1989             "To use archived non-system classes, this property must not be set", prop);
1990     _has_platform_or_app_classes = false;
1991   }
1992 
1993 
1994   if (!_verify_local && BytecodeVerificationLocal) {
1995     //  we cannot load boot classes, so there's no point of using the CDS archive
1996     AOTMetaspace::report_loading_error("The %s's BytecodeVerificationLocal setting (%s)"
1997                                           " does not equal the current BytecodeVerificationLocal setting (%s).", file_type,
1998                                           _verify_local ? "enabled" : "disabled",
1999                                           BytecodeVerificationLocal ? "enabled" : "disabled");
2000     return false;
2001   }
2002 
2003   // For backwards compatibility, we don't check the BytecodeVerificationRemote setting
2004   // if the archive only contains system classes.
2005   if (_has_platform_or_app_classes
2006       && !_verify_remote // we didn't verify the archived platform/app classes
2007       && BytecodeVerificationRemote) { // but we want to verify all loaded platform/app classes
2008     aot_log_info(aot)("The %s was created with less restrictive "
2009                                "verification setting than the current setting.", file_type);
2010     // Pretend that we didn't have any archived platform/app classes, so they won't be loaded
2011     // by SystemDictionaryShared.
2012     _has_platform_or_app_classes = false;
2013   }
2014 
2015   aot_log_info(aot)("The %s was created with UseCompressedOops = %d, UseCompactObjectHeaders = %d",
2016                           file_type, compressed_oops(), compact_headers());
2017   if (compressed_oops() != UseCompressedOops) {
2018     aot_log_warning(aot)("Unable to use %s.\nThe saved state of UseCompressedOops (%d) is "
2019                                "different from runtime (%d), CDS will be disabled.", file_type,
2020                                compressed_oops(), UseCompressedOops);
2021     return false;
2022   }
2023 
2024   if (is_static()) {
2025     const char* err = nullptr;
2026     if (Arguments::is_valhalla_enabled()) {
2027       if (!_has_valhalla_patched_classes) {
2028         err = "not created";
2029       }
2030     } else {
2031       if (_has_valhalla_patched_classes) {
2032         err = "created";
2033       }
2034     }
2035     if (err != nullptr) {
2036       log_warning(cds)("This archive was %s with --enable-preview. It is "
2037                          "incompatible with the current JVM setting", err);
2038       return false;
2039     }
2040   }
2041 
2042   if (compact_headers() != UseCompactObjectHeaders) {
2043     aot_log_warning(aot)("Unable to use %s.\nThe %s's UseCompactObjectHeaders setting (%s)"
2044                      " does not equal the current UseCompactObjectHeaders setting (%s).", file_type, file_type,
2045                      _compact_headers          ? "enabled" : "disabled",
2046                      UseCompactObjectHeaders   ? "enabled" : "disabled");
2047     return false;
2048   }
2049 
2050   if (!_use_optimized_module_handling && !CDSConfig::is_dumping_final_static_archive()) {
2051     CDSConfig::stop_using_optimized_module_handling();
2052     aot_log_info(aot)("optimized module handling: disabled because archive was created without optimized module handling");
2053   }
2054 
2055   if (is_static()) {
2056     // Only the static archive can contain the full module graph.
2057     if (!_has_full_module_graph) {
2058       CDSConfig::stop_using_full_module_graph("archive was created without full module graph");
2059     }
2060   }
2061 
2062   return true;
2063 }
2064 
2065 bool FileMapInfo::validate_header() {
2066   if (!header()->validate()) {
2067     return false;
2068   }
2069   if (_is_static) {
2070     return true;
2071   } else {
2072     return DynamicArchive::validate(this);
2073   }
2074 }
2075 
2076 #if INCLUDE_JVMTI
2077 ClassPathEntry** FileMapInfo::_classpath_entries_for_jvmti = nullptr;
2078 
2079 ClassPathEntry* FileMapInfo::get_classpath_entry_for_jvmti(int i, TRAPS) {
2080   if (i == 0) {
2081     // index 0 corresponds to the ClassPathImageEntry which is a globally shared object
2082     // and should never be deleted.
2083     return ClassLoader::get_jrt_entry();
2084   }
2085   ClassPathEntry* ent = _classpath_entries_for_jvmti[i];
2086   if (ent == nullptr) {
2087     const AOTClassLocation* cl = AOTClassLocationConfig::runtime()->class_location_at(i);
2088     const char* path = cl->path();
2089     struct stat st;
2090     if (os::stat(path, &st) != 0) {
2091       char *msg = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, strlen(path) + 128);
2092       jio_snprintf(msg, strlen(path) + 127, "error in finding JAR file %s", path);
2093       THROW_MSG_(vmSymbols::java_io_IOException(), msg, nullptr);
2094     } else {
2095       ent = ClassLoader::create_class_path_entry(THREAD, path, &st);
2096       if (ent == nullptr) {
2097         char *msg = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, strlen(path) + 128);
2098         jio_snprintf(msg, strlen(path) + 127, "error in opening JAR file %s", path);
2099         THROW_MSG_(vmSymbols::java_io_IOException(), msg, nullptr);
2100       }
2101     }
2102 
2103     MutexLocker mu(THREAD, CDSClassFileStream_lock);
2104     if (_classpath_entries_for_jvmti[i] == nullptr) {
2105       _classpath_entries_for_jvmti[i] = ent;
2106     } else {
2107       // Another thread has beat me to creating this entry
2108       delete ent;
2109       ent = _classpath_entries_for_jvmti[i];
2110     }
2111   }
2112 
2113   return ent;
2114 }
2115 
2116 ClassFileStream* FileMapInfo::open_stream_for_jvmti(InstanceKlass* ik, Handle class_loader, TRAPS) {
2117   int path_index = ik->shared_classpath_index();
2118   assert(path_index >= 0, "should be called for shared built-in classes only");
2119   assert(path_index < AOTClassLocationConfig::runtime()->length(), "sanity");
2120 
2121   ClassPathEntry* cpe = get_classpath_entry_for_jvmti(path_index, CHECK_NULL);
2122   assert(cpe != nullptr, "must be");
2123 
2124   Symbol* name = ik->name();
2125   const char* const class_name = name->as_C_string();
2126   const char* const file_name = ClassLoader::file_name_for_class_name(class_name,
2127                                                                       name->utf8_length());
2128   ClassLoaderData* loader_data = ClassLoaderData::class_loader_data(class_loader());
2129   const AOTClassLocation* cl = AOTClassLocationConfig::runtime()->class_location_at(path_index);
2130   ClassFileStream* cfs;
2131   if (class_loader() != nullptr && cl->is_multi_release_jar()) {
2132     // This class was loaded from a multi-release JAR file during dump time. The
2133     // process for finding its classfile is complex. Let's defer to the Java code
2134     // in java.lang.ClassLoader.
2135     cfs = get_stream_from_class_loader(class_loader, cpe, file_name, CHECK_NULL);
2136   } else {
2137     cfs = cpe->open_stream_for_loader(THREAD, file_name, loader_data);
2138   }
2139   assert(cfs != nullptr, "must be able to read the classfile data of shared classes for built-in loaders.");
2140   log_debug(aot, jvmti)("classfile data for %s [%d: %s] = %d bytes", class_name, path_index,
2141                         cfs->source(), cfs->length());
2142   return cfs;
2143 }
2144 
2145 ClassFileStream* FileMapInfo::get_stream_from_class_loader(Handle class_loader,
2146                                                            ClassPathEntry* cpe,
2147                                                            const char* file_name,
2148                                                            TRAPS) {
2149   JavaValue result(T_OBJECT);
2150   oop class_name = java_lang_String::create_oop_from_str(file_name, THREAD);
2151   Handle h_class_name = Handle(THREAD, class_name);
2152 
2153   // byte[] ClassLoader.getResourceAsByteArray(String name)
2154   JavaCalls::call_virtual(&result,
2155                           class_loader,
2156                           vmClasses::ClassLoader_klass(),
2157                           vmSymbols::getResourceAsByteArray_name(),
2158                           vmSymbols::getResourceAsByteArray_signature(),
2159                           h_class_name,
2160                           CHECK_NULL);
2161   assert(result.get_type() == T_OBJECT, "just checking");
2162   oop obj = result.get_oop();
2163   assert(obj != nullptr, "ClassLoader.getResourceAsByteArray should not return null");
2164 
2165   // copy from byte[] to a buffer
2166   typeArrayOop ba = typeArrayOop(obj);
2167   jint len = ba->length();
2168   u1* buffer = NEW_RESOURCE_ARRAY(u1, len);
2169   ArrayAccess<>::arraycopy_to_native<>(ba, typeArrayOopDesc::element_offset<jbyte>(0), buffer, len);
2170 
2171   return new ClassFileStream(buffer, len, cpe->name());
2172 }
2173 #endif