1 /*
   2  * Copyright (c) 1997, 2025, 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/aotLogging.hpp"
  26 #include "cds/cds_globals.hpp"
  27 #include "cds/cdsConfig.hpp"
  28 #include "classfile/classLoader.hpp"
  29 #include "classfile/javaAssertions.hpp"
  30 #include "classfile/moduleEntry.hpp"
  31 #include "classfile/stringTable.hpp"
  32 #include "classfile/symbolTable.hpp"
  33 #include "compiler/compilerDefinitions.hpp"
  34 #include "gc/shared/gcArguments.hpp"
  35 #include "gc/shared/gcConfig.hpp"
  36 #include "gc/shared/genArguments.hpp"
  37 #include "gc/shared/stringdedup/stringDedup.hpp"
  38 #include "gc/shared/tlab_globals.hpp"
  39 #include "jvm.h"
  40 #include "logging/log.hpp"
  41 #include "logging/logConfiguration.hpp"
  42 #include "logging/logStream.hpp"
  43 #include "logging/logTag.hpp"
  44 #include "memory/allocation.inline.hpp"
  45 #include "nmt/nmtCommon.hpp"
  46 #include "oops/compressedKlass.hpp"
  47 #include "oops/instanceKlass.hpp"
  48 #include "oops/objLayout.hpp"
  49 #include "oops/oop.inline.hpp"
  50 #include "prims/jvmtiAgentList.hpp"
  51 #include "prims/jvmtiExport.hpp"
  52 #include "runtime/arguments.hpp"
  53 #include "runtime/flags/jvmFlag.hpp"
  54 #include "runtime/flags/jvmFlagAccess.hpp"
  55 #include "runtime/flags/jvmFlagLimit.hpp"
  56 #include "runtime/globals_extension.hpp"
  57 #include "runtime/java.hpp"
  58 #include "runtime/os.hpp"
  59 #include "runtime/safepoint.hpp"
  60 #include "runtime/safepointMechanism.hpp"
  61 #include "runtime/synchronizer.hpp"
  62 #include "runtime/vm_version.hpp"
  63 #include "services/management.hpp"
  64 #include "utilities/align.hpp"
  65 #include "utilities/checkedCast.hpp"
  66 #include "utilities/debug.hpp"
  67 #include "utilities/defaultStream.hpp"
  68 #include "utilities/macros.hpp"
  69 #include "utilities/parseInteger.hpp"
  70 #include "utilities/powerOfTwo.hpp"
  71 #include "utilities/stringUtils.hpp"
  72 #include "utilities/systemMemoryBarrier.hpp"
  73 #if INCLUDE_JFR
  74 #include "jfr/jfr.hpp"
  75 #endif
  76 
  77 #include <limits>
  78 
  79 static const char _default_java_launcher[] = "generic";
  80 
  81 #define DEFAULT_JAVA_LAUNCHER _default_java_launcher
  82 
  83 char*  Arguments::_jvm_flags_file               = nullptr;
  84 char** Arguments::_jvm_flags_array              = nullptr;
  85 int    Arguments::_num_jvm_flags                = 0;
  86 char** Arguments::_jvm_args_array               = nullptr;
  87 int    Arguments::_num_jvm_args                 = 0;
  88 unsigned int Arguments::_addmods_count          = 0;
  89 #if INCLUDE_JVMCI
  90 bool   Arguments::_jvmci_module_added           = false;
  91 #endif
  92 char*  Arguments::_java_command                 = nullptr;
  93 SystemProperty* Arguments::_system_properties   = nullptr;
  94 size_t Arguments::_conservative_max_heap_alignment = 0;
  95 Arguments::Mode Arguments::_mode                = _mixed;
  96 const char*  Arguments::_java_vendor_url_bug    = nullptr;
  97 const char*  Arguments::_sun_java_launcher      = DEFAULT_JAVA_LAUNCHER;
  98 bool   Arguments::_executing_unit_tests         = false;
  99 
 100 // These parameters are reset in method parse_vm_init_args()
 101 bool   Arguments::_AlwaysCompileLoopMethods     = AlwaysCompileLoopMethods;
 102 bool   Arguments::_UseOnStackReplacement        = UseOnStackReplacement;
 103 bool   Arguments::_BackgroundCompilation        = BackgroundCompilation;
 104 bool   Arguments::_ClipInlining                 = ClipInlining;
 105 size_t Arguments::_default_SharedBaseAddress    = SharedBaseAddress;
 106 
 107 bool   Arguments::_enable_preview               = false;
 108 bool   Arguments::_has_jdwp_agent               = false;
 109 
 110 LegacyGCLogging Arguments::_legacyGCLogging     = { nullptr, 0 };
 111 
 112 // These are not set by the JDK's built-in launchers, but they can be set by
 113 // programs that embed the JVM using JNI_CreateJavaVM. See comments around
 114 // JavaVMOption in jni.h.
 115 abort_hook_t     Arguments::_abort_hook         = nullptr;
 116 exit_hook_t      Arguments::_exit_hook          = nullptr;
 117 vfprintf_hook_t  Arguments::_vfprintf_hook      = nullptr;
 118 
 119 
 120 SystemProperty *Arguments::_sun_boot_library_path = nullptr;
 121 SystemProperty *Arguments::_java_library_path = nullptr;
 122 SystemProperty *Arguments::_java_home = nullptr;
 123 SystemProperty *Arguments::_java_class_path = nullptr;
 124 SystemProperty *Arguments::_jdk_boot_class_path_append = nullptr;
 125 SystemProperty *Arguments::_vm_info = nullptr;
 126 
 127 GrowableArray<ModulePatchPath*> *Arguments::_patch_mod_prefix = nullptr;
 128 PathString *Arguments::_boot_class_path = nullptr;
 129 bool Arguments::_has_jimage = false;
 130 
 131 char* Arguments::_ext_dirs = nullptr;
 132 
 133 // True if -Xshare:auto option was specified.
 134 static bool xshare_auto_cmd_line = false;
 135 
 136 // True if -Xint/-Xmixed/-Xcomp were specified
 137 static bool mode_flag_cmd_line = false;
 138 
 139 struct VMInitArgsGroup {
 140   const JavaVMInitArgs* _args;
 141   JVMFlagOrigin _origin;
 142 };
 143 
 144 bool PathString::set_value(const char *value, AllocFailType alloc_failmode) {
 145   char* new_value = AllocateHeap(strlen(value)+1, mtArguments, alloc_failmode);
 146   if (new_value == nullptr) {
 147     assert(alloc_failmode == AllocFailStrategy::RETURN_NULL, "must be");
 148     return false;
 149   }
 150   if (_value != nullptr) {
 151     FreeHeap(_value);
 152   }
 153   _value = new_value;
 154   strcpy(_value, value);
 155   return true;
 156 }
 157 
 158 void PathString::append_value(const char *value) {
 159   char *sp;
 160   size_t len = 0;
 161   if (value != nullptr) {
 162     len = strlen(value);
 163     if (_value != nullptr) {
 164       len += strlen(_value);
 165     }
 166     sp = AllocateHeap(len+2, mtArguments);
 167     assert(sp != nullptr, "Unable to allocate space for new append path value");
 168     if (sp != nullptr) {
 169       if (_value != nullptr) {
 170         strcpy(sp, _value);
 171         strcat(sp, os::path_separator());
 172         strcat(sp, value);
 173         FreeHeap(_value);
 174       } else {
 175         strcpy(sp, value);
 176       }
 177       _value = sp;
 178     }
 179   }
 180 }
 181 
 182 PathString::PathString(const char* value) {
 183   if (value == nullptr) {
 184     _value = nullptr;
 185   } else {
 186     _value = AllocateHeap(strlen(value)+1, mtArguments);
 187     strcpy(_value, value);
 188   }
 189 }
 190 
 191 PathString::~PathString() {
 192   if (_value != nullptr) {
 193     FreeHeap(_value);
 194     _value = nullptr;
 195   }
 196 }
 197 
 198 ModulePatchPath::ModulePatchPath(const char* module_name, const char* path) {
 199   assert(module_name != nullptr && path != nullptr, "Invalid module name or path value");
 200   size_t len = strlen(module_name) + 1;
 201   _module_name = AllocateHeap(len, mtInternal);
 202   strncpy(_module_name, module_name, len); // copy the trailing null
 203   _path =  new PathString(path);
 204 }
 205 
 206 ModulePatchPath::~ModulePatchPath() {
 207   if (_module_name != nullptr) {
 208     FreeHeap(_module_name);
 209     _module_name = nullptr;
 210   }
 211   if (_path != nullptr) {
 212     delete _path;
 213     _path = nullptr;
 214   }
 215 }
 216 
 217 SystemProperty::SystemProperty(const char* key, const char* value, bool writeable, bool internal) : PathString(value) {
 218   if (key == nullptr) {
 219     _key = nullptr;
 220   } else {
 221     _key = AllocateHeap(strlen(key)+1, mtArguments);
 222     strcpy(_key, key);
 223   }
 224   _next = nullptr;
 225   _internal = internal;
 226   _writeable = writeable;
 227 }
 228 
 229 // Check if head of 'option' matches 'name', and sets 'tail' to the remaining
 230 // part of the option string.
 231 static bool match_option(const JavaVMOption *option, const char* name,
 232                          const char** tail) {
 233   size_t len = strlen(name);
 234   if (strncmp(option->optionString, name, len) == 0) {
 235     *tail = option->optionString + len;
 236     return true;
 237   } else {
 238     return false;
 239   }
 240 }
 241 
 242 // Check if 'option' matches 'name'. No "tail" is allowed.
 243 static bool match_option(const JavaVMOption *option, const char* name) {
 244   const char* tail = nullptr;
 245   bool result = match_option(option, name, &tail);
 246   if (tail != nullptr && *tail == '\0') {
 247     return result;
 248   } else {
 249     return false;
 250   }
 251 }
 252 
 253 // Return true if any of the strings in null-terminated array 'names' matches.
 254 // If tail_allowed is true, then the tail must begin with a colon; otherwise,
 255 // the option must match exactly.
 256 static bool match_option(const JavaVMOption* option, const char** names, const char** tail,
 257   bool tail_allowed) {
 258   for (/* empty */; *names != nullptr; ++names) {
 259   if (match_option(option, *names, tail)) {
 260       if (**tail == '\0' || (tail_allowed && **tail == ':')) {
 261         return true;
 262       }
 263     }
 264   }
 265   return false;
 266 }
 267 
 268 #if INCLUDE_JFR
 269 static bool _has_jfr_option = false;  // is using JFR
 270 
 271 // return true on failure
 272 static bool match_jfr_option(const JavaVMOption** option) {
 273   assert((*option)->optionString != nullptr, "invariant");
 274   char* tail = nullptr;
 275   if (match_option(*option, "-XX:StartFlightRecording", (const char**)&tail)) {
 276     _has_jfr_option = true;
 277     return Jfr::on_start_flight_recording_option(option, tail);
 278   } else if (match_option(*option, "-XX:FlightRecorderOptions", (const char**)&tail)) {
 279     _has_jfr_option = true;
 280     return Jfr::on_flight_recorder_option(option, tail);
 281   }
 282   return false;
 283 }
 284 
 285 bool Arguments::has_jfr_option() {
 286   return _has_jfr_option;
 287 }
 288 #endif
 289 
 290 static void logOption(const char* opt) {
 291   if (PrintVMOptions) {
 292     jio_fprintf(defaultStream::output_stream(), "VM option '%s'\n", opt);
 293   }
 294 }
 295 
 296 bool needs_module_property_warning = false;
 297 
 298 #define MODULE_PROPERTY_PREFIX "jdk.module."
 299 #define MODULE_PROPERTY_PREFIX_LEN 11
 300 #define ADDEXPORTS "addexports"
 301 #define ADDEXPORTS_LEN 10
 302 #define ADDREADS "addreads"
 303 #define ADDREADS_LEN 8
 304 #define ADDOPENS "addopens"
 305 #define ADDOPENS_LEN 8
 306 #define PATCH "patch"
 307 #define PATCH_LEN 5
 308 #define ADDMODS "addmods"
 309 #define ADDMODS_LEN 7
 310 #define LIMITMODS "limitmods"
 311 #define LIMITMODS_LEN 9
 312 #define PATH "path"
 313 #define PATH_LEN 4
 314 #define UPGRADE_PATH "upgrade.path"
 315 #define UPGRADE_PATH_LEN 12
 316 #define ENABLE_NATIVE_ACCESS "enable.native.access"
 317 #define ENABLE_NATIVE_ACCESS_LEN 20
 318 #define ILLEGAL_NATIVE_ACCESS "illegal.native.access"
 319 #define ILLEGAL_NATIVE_ACCESS_LEN 21
 320 
 321 // Return TRUE if option matches 'property', or 'property=', or 'property.'.
 322 static bool matches_property_suffix(const char* option, const char* property, size_t len) {
 323   return ((strncmp(option, property, len) == 0) &&
 324           (option[len] == '=' || option[len] == '.' || option[len] == '\0'));
 325 }
 326 
 327 // Return true if property starts with "jdk.module." and its ensuing chars match
 328 // any of the reserved module properties.
 329 // property should be passed without the leading "-D".
 330 bool Arguments::is_internal_module_property(const char* property) {
 331   return internal_module_property_helper(property, false);
 332 }
 333 
 334 // Returns true if property is one of those recognized by is_internal_module_property() but
 335 // is not supported by CDS archived full module graph.
 336 bool Arguments::is_incompatible_cds_internal_module_property(const char* property) {
 337   return internal_module_property_helper(property, true);
 338 }
 339 
 340 bool Arguments::internal_module_property_helper(const char* property, bool check_for_cds) {
 341   if (strncmp(property, MODULE_PROPERTY_PREFIX, MODULE_PROPERTY_PREFIX_LEN) == 0) {
 342     const char* property_suffix = property + MODULE_PROPERTY_PREFIX_LEN;
 343     if (matches_property_suffix(property_suffix, PATCH, PATCH_LEN) ||
 344         matches_property_suffix(property_suffix, LIMITMODS, LIMITMODS_LEN) ||
 345         matches_property_suffix(property_suffix, UPGRADE_PATH, UPGRADE_PATH_LEN) ||
 346         matches_property_suffix(property_suffix, ILLEGAL_NATIVE_ACCESS, ILLEGAL_NATIVE_ACCESS_LEN)) {
 347       return true;
 348     }
 349 
 350     if (!check_for_cds) {
 351       // CDS notes: these properties are supported by CDS archived full module graph.
 352       if (matches_property_suffix(property_suffix, ADDEXPORTS, ADDEXPORTS_LEN) ||
 353           matches_property_suffix(property_suffix, ADDOPENS, ADDOPENS_LEN) ||
 354           matches_property_suffix(property_suffix, ADDREADS, ADDREADS_LEN) ||
 355           matches_property_suffix(property_suffix, PATH, PATH_LEN) ||
 356           matches_property_suffix(property_suffix, ADDMODS, ADDMODS_LEN) ||
 357           matches_property_suffix(property_suffix, ENABLE_NATIVE_ACCESS, ENABLE_NATIVE_ACCESS_LEN)) {
 358         return true;
 359       }
 360     }
 361   }
 362   return false;
 363 }
 364 
 365 // Process java launcher properties.
 366 void Arguments::process_sun_java_launcher_properties(JavaVMInitArgs* args) {
 367   // See if sun.java.launcher is defined.
 368   // Must do this before setting up other system properties,
 369   // as some of them may depend on launcher type.
 370   for (int index = 0; index < args->nOptions; index++) {
 371     const JavaVMOption* option = args->options + index;
 372     const char* tail;
 373 
 374     if (match_option(option, "-Dsun.java.launcher=", &tail)) {
 375       process_java_launcher_argument(tail, option->extraInfo);
 376       continue;
 377     }
 378     if (match_option(option, "-XX:+ExecutingUnitTests")) {
 379       _executing_unit_tests = true;
 380       continue;
 381     }
 382   }
 383 }
 384 
 385 // Initialize system properties key and value.
 386 void Arguments::init_system_properties() {
 387 
 388   // Set up _boot_class_path which is not a property but
 389   // relies heavily on argument processing and the jdk.boot.class.path.append
 390   // property. It is used to store the underlying boot class path.
 391   _boot_class_path = new PathString(nullptr);
 392 
 393   PropertyList_add(&_system_properties, new SystemProperty("java.vm.specification.name",
 394                                                            "Java Virtual Machine Specification",  false));
 395   PropertyList_add(&_system_properties, new SystemProperty("java.vm.version", VM_Version::vm_release(),  false));
 396   PropertyList_add(&_system_properties, new SystemProperty("java.vm.name", VM_Version::vm_name(),  false));
 397   PropertyList_add(&_system_properties, new SystemProperty("jdk.debug", VM_Version::jdk_debug_level(),  false));
 398 
 399   // Initialize the vm.info now, but it will need updating after argument parsing.
 400   _vm_info = new SystemProperty("java.vm.info", VM_Version::vm_info_string(), true);
 401 
 402   // Following are JVMTI agent writable properties.
 403   // Properties values are set to nullptr and they are
 404   // os specific they are initialized in os::init_system_properties_values().
 405   _sun_boot_library_path = new SystemProperty("sun.boot.library.path", nullptr,  true);
 406   _java_library_path = new SystemProperty("java.library.path", nullptr,  true);
 407   _java_home =  new SystemProperty("java.home", nullptr,  true);
 408   _java_class_path = new SystemProperty("java.class.path", "",  true);
 409   // jdk.boot.class.path.append is a non-writeable, internal property.
 410   // It can only be set by either:
 411   //    - -Xbootclasspath/a:
 412   //    - AddToBootstrapClassLoaderSearch during JVMTI OnLoad phase
 413   _jdk_boot_class_path_append = new SystemProperty("jdk.boot.class.path.append", nullptr, false, true);
 414 
 415   // Add to System Property list.
 416   PropertyList_add(&_system_properties, _sun_boot_library_path);
 417   PropertyList_add(&_system_properties, _java_library_path);
 418   PropertyList_add(&_system_properties, _java_home);
 419   PropertyList_add(&_system_properties, _java_class_path);
 420   PropertyList_add(&_system_properties, _jdk_boot_class_path_append);
 421   PropertyList_add(&_system_properties, _vm_info);
 422 
 423   // Set OS specific system properties values
 424   os::init_system_properties_values();
 425 }
 426 
 427 // Update/Initialize System properties after JDK version number is known
 428 void Arguments::init_version_specific_system_properties() {
 429   enum { bufsz = 16 };
 430   char buffer[bufsz];
 431   const char* spec_vendor = "Oracle Corporation";
 432   uint32_t spec_version = JDK_Version::current().major_version();
 433 
 434   jio_snprintf(buffer, bufsz, UINT32_FORMAT, spec_version);
 435 
 436   PropertyList_add(&_system_properties,
 437       new SystemProperty("java.vm.specification.vendor",  spec_vendor, false));
 438   PropertyList_add(&_system_properties,
 439       new SystemProperty("java.vm.specification.version", buffer, false));
 440   PropertyList_add(&_system_properties,
 441       new SystemProperty("java.vm.vendor", VM_Version::vm_vendor(),  false));
 442 }
 443 
 444 /*
 445  *  -XX argument processing:
 446  *
 447  *  -XX arguments are defined in several places, such as:
 448  *      globals.hpp, globals_<cpu>.hpp, globals_<os>.hpp, <compiler>_globals.hpp, or <gc>_globals.hpp.
 449  *  -XX arguments are parsed in parse_argument().
 450  *  -XX argument bounds checking is done in check_vm_args_consistency().
 451  *
 452  * Over time -XX arguments may change. There are mechanisms to handle common cases:
 453  *
 454  *      ALIASED: An option that is simply another name for another option. This is often
 455  *               part of the process of deprecating a flag, but not all aliases need
 456  *               to be deprecated.
 457  *
 458  *               Create an alias for an option by adding the old and new option names to the
 459  *               "aliased_jvm_flags" table. Delete the old variable from globals.hpp (etc).
 460  *
 461  *   DEPRECATED: An option that is supported, but a warning is printed to let the user know that
 462  *               support may be removed in the future. Both regular and aliased options may be
 463  *               deprecated.
 464  *
 465  *               Add a deprecation warning for an option (or alias) by adding an entry in the
 466  *               "special_jvm_flags" table and setting the "deprecated_in" field.
 467  *               Often an option "deprecated" in one major release will
 468  *               be made "obsolete" in the next. In this case the entry should also have its
 469  *               "obsolete_in" field set.
 470  *
 471  *     OBSOLETE: An option that has been removed (and deleted from globals.hpp), but is still accepted
 472  *               on the command line. A warning is printed to let the user know that option might not
 473  *               be accepted in the future.
 474  *
 475  *               Add an obsolete warning for an option by adding an entry in the "special_jvm_flags"
 476  *               table and setting the "obsolete_in" field.
 477  *
 478  *      EXPIRED: A deprecated or obsolete option that has an "accept_until" version less than or equal
 479  *               to the current JDK version. The system will flatly refuse to admit the existence of
 480  *               the flag. This allows a flag to die automatically over JDK releases.
 481  *
 482  *               Note that manual cleanup of expired options should be done at major JDK version upgrades:
 483  *                  - Newly expired options should be removed from the special_jvm_flags and aliased_jvm_flags tables.
 484  *                  - Newly obsolete or expired deprecated options should have their global variable
 485  *                    definitions removed (from globals.hpp, etc) and related implementations removed.
 486  *
 487  * Recommended approach for removing options:
 488  *
 489  * To remove options commonly used by customers (e.g. product -XX options), use
 490  * the 3-step model adding major release numbers to the deprecate, obsolete and expire columns.
 491  *
 492  * To remove internal options (e.g. diagnostic, experimental, develop options), use
 493  * a 2-step model adding major release numbers to the obsolete and expire columns.
 494  *
 495  * To change the name of an option, use the alias table as well as a 2-step
 496  * model adding major release numbers to the deprecate and expire columns.
 497  * Think twice about aliasing commonly used customer options.
 498  *
 499  * There are times when it is appropriate to leave a future release number as undefined.
 500  *
 501  * Tests:  Aliases should be tested in VMAliasOptions.java.
 502  *         Deprecated options should be tested in VMDeprecatedOptions.java.
 503  */
 504 
 505 // The special_jvm_flags table declares options that are being deprecated and/or obsoleted. The
 506 // "deprecated_in" or "obsolete_in" fields may be set to "undefined", but not both.
 507 // When the JDK version reaches 'deprecated_in' limit, the JVM will process this flag on
 508 // the command-line as usual, but will issue a warning.
 509 // When the JDK version reaches 'obsolete_in' limit, the JVM will continue accepting this flag on
 510 // the command-line, while issuing a warning and ignoring the flag value.
 511 // Once the JDK version reaches 'expired_in' limit, the JVM will flatly refuse to admit the
 512 // existence of the flag.
 513 //
 514 // MANUAL CLEANUP ON JDK VERSION UPDATES:
 515 // This table ensures that the handling of options will update automatically when the JDK
 516 // version is incremented, but the source code needs to be cleanup up manually:
 517 // - As "deprecated" options age into "obsolete" or "expired" options, the associated "globals"
 518 //   variable should be removed, as well as users of the variable.
 519 // - As "deprecated" options age into "obsolete" options, move the entry into the
 520 //   "Obsolete Flags" section of the table.
 521 // - All expired options should be removed from the table.
 522 static SpecialFlag const special_jvm_flags[] = {
 523   // -------------- Deprecated Flags --------------
 524   // --- Non-alias flags - sorted by obsolete_in then expired_in:
 525   { "AllowRedefinitionToAddDeleteMethods", JDK_Version::jdk(13), JDK_Version::undefined(), JDK_Version::undefined() },
 526   { "FlightRecorder",               JDK_Version::jdk(13), JDK_Version::undefined(), JDK_Version::undefined() },
 527   { "DumpSharedSpaces",             JDK_Version::jdk(18), JDK_Version::jdk(19), JDK_Version::undefined() },
 528   { "DynamicDumpSharedSpaces",      JDK_Version::jdk(18), JDK_Version::jdk(19), JDK_Version::undefined() },
 529   { "RequireSharedSpaces",          JDK_Version::jdk(18), JDK_Version::jdk(19), JDK_Version::undefined() },
 530   { "UseSharedSpaces",              JDK_Version::jdk(18), JDK_Version::jdk(19), JDK_Version::undefined() },
 531   { "LockingMode",                  JDK_Version::jdk(24), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 532 #ifdef _LP64
 533   { "UseCompressedClassPointers",   JDK_Version::jdk(25),  JDK_Version::jdk(26), JDK_Version::undefined() },
 534 #endif
 535   { "ParallelRefProcEnabled",       JDK_Version::jdk(26),  JDK_Version::jdk(27), JDK_Version::jdk(28) },
 536   { "ParallelRefProcBalancingEnabled", JDK_Version::jdk(26),  JDK_Version::jdk(27), JDK_Version::jdk(28) },
 537   { "PSChunkLargeArrays",           JDK_Version::jdk(26),  JDK_Version::jdk(27), JDK_Version::jdk(28) },
 538   // --- Deprecated alias flags (see also aliased_jvm_flags) - sorted by obsolete_in then expired_in:
 539   { "CreateMinidumpOnCrash",        JDK_Version::jdk(9),  JDK_Version::undefined(), JDK_Version::undefined() },
 540 
 541   // -------------- Obsolete Flags - sorted by expired_in --------------
 542 
 543 #ifdef LINUX
 544   { "UseOprofile",                  JDK_Version::jdk(25), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 545 #endif
 546   { "MetaspaceReclaimPolicy",       JDK_Version::undefined(), JDK_Version::jdk(21), JDK_Version::undefined() },
 547   { "ZGenerational",                JDK_Version::jdk(23), JDK_Version::jdk(24), JDK_Version::undefined() },
 548   { "ZMarkStackSpaceLimit",         JDK_Version::undefined(), JDK_Version::jdk(25), JDK_Version::undefined() },
 549   { "G1UpdateBufferSize",           JDK_Version::undefined(), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 550 #if defined(AARCH64)
 551   { "NearCpool",                    JDK_Version::undefined(), JDK_Version::jdk(25), JDK_Version::undefined() },
 552 #endif
 553 
 554   { "AdaptiveSizeMajorGCDecayTimeScale",                JDK_Version::undefined(), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 555   { "AdaptiveSizePolicyInitializingSteps",              JDK_Version::undefined(), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 556   { "AdaptiveSizePolicyOutputInterval",                 JDK_Version::undefined(), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 557   { "AdaptiveSizeThroughPutPolicy",                     JDK_Version::undefined(), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 558   { "AdaptiveTimeWeight",                               JDK_Version::undefined(), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 559   { "PausePadding",                                     JDK_Version::undefined(), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 560   { "SurvivorPadding",                                  JDK_Version::undefined(), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 561   { "TenuredGenerationSizeIncrement",                   JDK_Version::undefined(), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 562   { "TenuredGenerationSizeSupplement",                  JDK_Version::undefined(), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 563   { "TenuredGenerationSizeSupplementDecay",             JDK_Version::undefined(), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 564   { "UseAdaptiveGenerationSizePolicyAtMajorCollection", JDK_Version::undefined(), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 565   { "UseAdaptiveGenerationSizePolicyAtMinorCollection", JDK_Version::undefined(), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 566   { "UseAdaptiveSizeDecayMajorGCCost",                  JDK_Version::undefined(), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 567   { "UseAdaptiveSizePolicyFootprintGoal",               JDK_Version::undefined(), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 568   { "UseAdaptiveSizePolicyWithSystemGC",                JDK_Version::undefined(), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 569   { "UsePSAdaptiveSurvivorSizePolicy",                  JDK_Version::undefined(), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 570 
 571   { "PretenureSizeThreshold",       JDK_Version::undefined(), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 572   { "HeapMaximumCompactionInterval",JDK_Version::undefined(), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 573 
 574 #ifdef ASSERT
 575   { "DummyObsoleteTestFlag",        JDK_Version::undefined(), JDK_Version::jdk(18), JDK_Version::undefined() },
 576 #endif
 577 
 578 #ifdef TEST_VERIFY_SPECIAL_JVM_FLAGS
 579   // These entries will generate build errors.  Their purpose is to test the macros.
 580   { "dep > obs",                    JDK_Version::jdk(9), JDK_Version::jdk(8), JDK_Version::undefined() },
 581   { "dep > exp ",                   JDK_Version::jdk(9), JDK_Version::undefined(), JDK_Version::jdk(8) },
 582   { "obs > exp ",                   JDK_Version::undefined(), JDK_Version::jdk(9), JDK_Version::jdk(8) },
 583   { "obs > exp",                    JDK_Version::jdk(8), JDK_Version::undefined(), JDK_Version::jdk(10) },
 584   { "not deprecated or obsolete",   JDK_Version::undefined(), JDK_Version::undefined(), JDK_Version::jdk(9) },
 585   { "dup option",                   JDK_Version::jdk(9), JDK_Version::undefined(), JDK_Version::undefined() },
 586   { "dup option",                   JDK_Version::jdk(9), JDK_Version::undefined(), JDK_Version::undefined() },
 587 #endif
 588 
 589   { nullptr, JDK_Version(0), JDK_Version(0) }
 590 };
 591 
 592 // Flags that are aliases for other flags.
 593 typedef struct {
 594   const char* alias_name;
 595   const char* real_name;
 596 } AliasedFlag;
 597 
 598 static AliasedFlag const aliased_jvm_flags[] = {
 599   { "CreateMinidumpOnCrash",    "CreateCoredumpOnCrash" },
 600   { nullptr, nullptr}
 601 };
 602 
 603 // Return true if "v" is less than "other", where "other" may be "undefined".
 604 static bool version_less_than(JDK_Version v, JDK_Version other) {
 605   assert(!v.is_undefined(), "must be defined");
 606   if (!other.is_undefined() && v.compare(other) >= 0) {
 607     return false;
 608   } else {
 609     return true;
 610   }
 611 }
 612 
 613 static bool lookup_special_flag(const char *flag_name, SpecialFlag& flag) {
 614   for (size_t i = 0; special_jvm_flags[i].name != nullptr; i++) {
 615     if ((strcmp(special_jvm_flags[i].name, flag_name) == 0)) {
 616       flag = special_jvm_flags[i];
 617       return true;
 618     }
 619   }
 620   return false;
 621 }
 622 
 623 bool Arguments::is_obsolete_flag(const char *flag_name, JDK_Version* version) {
 624   assert(version != nullptr, "Must provide a version buffer");
 625   SpecialFlag flag;
 626   if (lookup_special_flag(flag_name, flag)) {
 627     if (!flag.obsolete_in.is_undefined()) {
 628       if (!version_less_than(JDK_Version::current(), flag.obsolete_in)) {
 629         *version = flag.obsolete_in;
 630         // This flag may have been marked for obsoletion in this version, but we may not
 631         // have actually removed it yet. Rather than ignoring it as soon as we reach
 632         // this version we allow some time for the removal to happen. So if the flag
 633         // still actually exists we process it as normal, but issue an adjusted warning.
 634         const JVMFlag *real_flag = JVMFlag::find_declared_flag(flag_name);
 635         if (real_flag != nullptr) {
 636           char version_str[256];
 637           version->to_string(version_str, sizeof(version_str));
 638           warning("Temporarily processing option %s; support is scheduled for removal in %s",
 639                   flag_name, version_str);
 640           return false;
 641         }
 642         return true;
 643       }
 644     }
 645   }
 646   return false;
 647 }
 648 
 649 int Arguments::is_deprecated_flag(const char *flag_name, JDK_Version* version) {
 650   assert(version != nullptr, "Must provide a version buffer");
 651   SpecialFlag flag;
 652   if (lookup_special_flag(flag_name, flag)) {
 653     if (!flag.deprecated_in.is_undefined()) {
 654       if (version_less_than(JDK_Version::current(), flag.obsolete_in) &&
 655           version_less_than(JDK_Version::current(), flag.expired_in)) {
 656         *version = flag.deprecated_in;
 657         return 1;
 658       } else {
 659         return -1;
 660       }
 661     }
 662   }
 663   return 0;
 664 }
 665 
 666 const char* Arguments::real_flag_name(const char *flag_name) {
 667   for (size_t i = 0; aliased_jvm_flags[i].alias_name != nullptr; i++) {
 668     const AliasedFlag& flag_status = aliased_jvm_flags[i];
 669     if (strcmp(flag_status.alias_name, flag_name) == 0) {
 670         return flag_status.real_name;
 671     }
 672   }
 673   return flag_name;
 674 }
 675 
 676 #ifdef ASSERT
 677 static bool lookup_special_flag(const char *flag_name, size_t skip_index) {
 678   for (size_t i = 0; special_jvm_flags[i].name != nullptr; i++) {
 679     if ((i != skip_index) && (strcmp(special_jvm_flags[i].name, flag_name) == 0)) {
 680       return true;
 681     }
 682   }
 683   return false;
 684 }
 685 
 686 // Verifies the correctness of the entries in the special_jvm_flags table.
 687 // If there is a semantic error (i.e. a bug in the table) such as the obsoletion
 688 // version being earlier than the deprecation version, then a warning is issued
 689 // and verification fails - by returning false. If it is detected that the table
 690 // is out of date, with respect to the current version, then ideally a warning is
 691 // issued but verification does not fail. This allows the VM to operate when the
 692 // version is first updated, without needing to update all the impacted flags at
 693 // the same time. In practice we can't issue the warning immediately when the version
 694 // is updated as it occurs for every test and some tests are not prepared to handle
 695 // unexpected output - see 8196739. Instead we only check if the table is up-to-date
 696 // if the check_globals flag is true, and in addition allow a grace period and only
 697 // check for stale flags when we hit build 25 (which is far enough into the 6 month
 698 // release cycle that all flag updates should have been processed, whilst still
 699 // leaving time to make the change before RDP2).
 700 // We use a gtest to call this, passing true, so that we can detect stale flags before
 701 // the end of the release cycle.
 702 
 703 static const int SPECIAL_FLAG_VALIDATION_BUILD = 25;
 704 
 705 bool Arguments::verify_special_jvm_flags(bool check_globals) {
 706   bool success = true;
 707   for (size_t i = 0; special_jvm_flags[i].name != nullptr; i++) {
 708     const SpecialFlag& flag = special_jvm_flags[i];
 709     if (lookup_special_flag(flag.name, i)) {
 710       warning("Duplicate special flag declaration \"%s\"", flag.name);
 711       success = false;
 712     }
 713     if (flag.deprecated_in.is_undefined() &&
 714         flag.obsolete_in.is_undefined()) {
 715       warning("Special flag entry \"%s\" must declare version deprecated and/or obsoleted in.", flag.name);
 716       success = false;
 717     }
 718 
 719     if (!flag.deprecated_in.is_undefined()) {
 720       if (!version_less_than(flag.deprecated_in, flag.obsolete_in)) {
 721         warning("Special flag entry \"%s\" must be deprecated before obsoleted.", flag.name);
 722         success = false;
 723       }
 724 
 725       if (!version_less_than(flag.deprecated_in, flag.expired_in)) {
 726         warning("Special flag entry \"%s\" must be deprecated before expired.", flag.name);
 727         success = false;
 728       }
 729     }
 730 
 731     if (!flag.obsolete_in.is_undefined()) {
 732       if (!version_less_than(flag.obsolete_in, flag.expired_in)) {
 733         warning("Special flag entry \"%s\" must be obsoleted before expired.", flag.name);
 734         success = false;
 735       }
 736 
 737       // if flag has become obsolete it should not have a "globals" flag defined anymore.
 738       if (check_globals && VM_Version::vm_build_number() >= SPECIAL_FLAG_VALIDATION_BUILD &&
 739           !version_less_than(JDK_Version::current(), flag.obsolete_in)) {
 740         if (JVMFlag::find_declared_flag(flag.name) != nullptr) {
 741           warning("Global variable for obsolete special flag entry \"%s\" should be removed", flag.name);
 742           success = false;
 743         }
 744       }
 745 
 746     } else if (!flag.expired_in.is_undefined()) {
 747       warning("Special flag entry \"%s\" must be explicitly obsoleted before expired.", flag.name);
 748       success = false;
 749     }
 750 
 751     if (!flag.expired_in.is_undefined()) {
 752       // if flag has become expired it should not have a "globals" flag defined anymore.
 753       if (check_globals && VM_Version::vm_build_number() >= SPECIAL_FLAG_VALIDATION_BUILD &&
 754           !version_less_than(JDK_Version::current(), flag.expired_in)) {
 755         if (JVMFlag::find_declared_flag(flag.name) != nullptr) {
 756           warning("Global variable for expired flag entry \"%s\" should be removed", flag.name);
 757           success = false;
 758         }
 759       }
 760     }
 761   }
 762   return success;
 763 }
 764 #endif
 765 
 766 bool Arguments::atojulong(const char *s, julong* result) {
 767   return parse_integer(s, result);
 768 }
 769 
 770 Arguments::ArgsRange Arguments::check_memory_size(julong size, julong min_size, julong max_size) {
 771   if (size < min_size) return arg_too_small;
 772   if (size > max_size) return arg_too_big;
 773   return arg_in_range;
 774 }
 775 
 776 // Describe an argument out of range error
 777 void Arguments::describe_range_error(ArgsRange errcode) {
 778   switch(errcode) {
 779   case arg_too_big:
 780     jio_fprintf(defaultStream::error_stream(),
 781                 "The specified size exceeds the maximum "
 782                 "representable size.\n");
 783     break;
 784   case arg_too_small:
 785   case arg_unreadable:
 786   case arg_in_range:
 787     // do nothing for now
 788     break;
 789   default:
 790     ShouldNotReachHere();
 791   }
 792 }
 793 
 794 static bool set_bool_flag(JVMFlag* flag, bool value, JVMFlagOrigin origin) {
 795   if (JVMFlagAccess::set_bool(flag, &value, origin) == JVMFlag::SUCCESS) {
 796     return true;
 797   } else {
 798     return false;
 799   }
 800 }
 801 
 802 static bool set_fp_numeric_flag(JVMFlag* flag, const char* value, JVMFlagOrigin origin) {
 803   // strtod allows leading whitespace, but our flag format does not.
 804   if (*value == '\0' || isspace((unsigned char) *value)) {
 805     return false;
 806   }
 807   char* end;
 808   errno = 0;
 809   double v = strtod(value, &end);
 810   if ((errno != 0) || (*end != 0)) {
 811     return false;
 812   }
 813   if (g_isnan(v) || !g_isfinite(v)) {
 814     // Currently we cannot handle these special values.
 815     return false;
 816   }
 817 
 818   if (JVMFlagAccess::set_double(flag, &v, origin) == JVMFlag::SUCCESS) {
 819     return true;
 820   }
 821   return false;
 822 }
 823 
 824 static bool set_numeric_flag(JVMFlag* flag, const char* value, JVMFlagOrigin origin) {
 825   JVMFlag::Error result = JVMFlag::WRONG_FORMAT;
 826 
 827   if (flag->is_int()) {
 828     int v;
 829     if (parse_integer(value, &v)) {
 830       result = JVMFlagAccess::set_int(flag, &v, origin);
 831     }
 832   } else if (flag->is_uint()) {
 833     uint v;
 834     if (parse_integer(value, &v)) {
 835       result = JVMFlagAccess::set_uint(flag, &v, origin);
 836     }
 837   } else if (flag->is_intx()) {
 838     intx v;
 839     if (parse_integer(value, &v)) {
 840       result = JVMFlagAccess::set_intx(flag, &v, origin);
 841     }
 842   } else if (flag->is_uintx()) {
 843     uintx v;
 844     if (parse_integer(value, &v)) {
 845       result = JVMFlagAccess::set_uintx(flag, &v, origin);
 846     }
 847   } else if (flag->is_uint64_t()) {
 848     uint64_t v;
 849     if (parse_integer(value, &v)) {
 850       result = JVMFlagAccess::set_uint64_t(flag, &v, origin);
 851     }
 852   } else if (flag->is_size_t()) {
 853     size_t v;
 854     if (parse_integer(value, &v)) {
 855       result = JVMFlagAccess::set_size_t(flag, &v, origin);
 856     }
 857   }
 858 
 859   return result == JVMFlag::SUCCESS;
 860 }
 861 
 862 static bool set_string_flag(JVMFlag* flag, const char* value, JVMFlagOrigin origin) {
 863   if (value[0] == '\0') {
 864     value = nullptr;
 865   }
 866   if (JVMFlagAccess::set_ccstr(flag, &value, origin) != JVMFlag::SUCCESS) return false;
 867   // Contract:  JVMFlag always returns a pointer that needs freeing.
 868   FREE_C_HEAP_ARRAY(char, value);
 869   return true;
 870 }
 871 
 872 static bool append_to_string_flag(JVMFlag* flag, const char* new_value, JVMFlagOrigin origin) {
 873   const char* old_value = "";
 874   if (JVMFlagAccess::get_ccstr(flag, &old_value) != JVMFlag::SUCCESS) return false;
 875   size_t old_len = old_value != nullptr ? strlen(old_value) : 0;
 876   size_t new_len = strlen(new_value);
 877   const char* value;
 878   char* free_this_too = nullptr;
 879   if (old_len == 0) {
 880     value = new_value;
 881   } else if (new_len == 0) {
 882     value = old_value;
 883   } else {
 884      size_t length = old_len + 1 + new_len + 1;
 885      char* buf = NEW_C_HEAP_ARRAY(char, length, mtArguments);
 886     // each new setting adds another LINE to the switch:
 887     jio_snprintf(buf, length, "%s\n%s", old_value, new_value);
 888     value = buf;
 889     free_this_too = buf;
 890   }
 891   (void) JVMFlagAccess::set_ccstr(flag, &value, origin);
 892   // JVMFlag always returns a pointer that needs freeing.
 893   FREE_C_HEAP_ARRAY(char, value);
 894   // JVMFlag made its own copy, so I must delete my own temp. buffer.
 895   FREE_C_HEAP_ARRAY(char, free_this_too);
 896   return true;
 897 }
 898 
 899 const char* Arguments::handle_aliases_and_deprecation(const char* arg) {
 900   const char* real_name = real_flag_name(arg);
 901   JDK_Version since = JDK_Version();
 902   switch (is_deprecated_flag(arg, &since)) {
 903   case -1: {
 904       // Obsolete or expired, so don't process normally,
 905       // but allow for an obsolete flag we're still
 906       // temporarily allowing.
 907       if (!is_obsolete_flag(arg, &since)) {
 908         return real_name;
 909       }
 910       // Note if we're not considered obsolete then we can't be expired either
 911       // as obsoletion must come first.
 912       return nullptr;
 913     }
 914     case 0:
 915       return real_name;
 916     case 1: {
 917       char version[256];
 918       since.to_string(version, sizeof(version));
 919       if (real_name != arg) {
 920         warning("Option %s was deprecated in version %s and will likely be removed in a future release. Use option %s instead.",
 921                 arg, version, real_name);
 922       } else {
 923         warning("Option %s was deprecated in version %s and will likely be removed in a future release.",
 924                 arg, version);
 925       }
 926       return real_name;
 927     }
 928   }
 929   ShouldNotReachHere();
 930   return nullptr;
 931 }
 932 
 933 #define BUFLEN 255
 934 
 935 JVMFlag* Arguments::find_jvm_flag(const char* name, size_t name_length) {
 936   char name_copied[BUFLEN+1];
 937   if (name[name_length] != 0) {
 938     if (name_length > BUFLEN) {
 939       return nullptr;
 940     } else {
 941       strncpy(name_copied, name, name_length);
 942       name_copied[name_length] = '\0';
 943       name = name_copied;
 944     }
 945   }
 946 
 947   const char* real_name = Arguments::handle_aliases_and_deprecation(name);
 948   if (real_name == nullptr) {
 949     return nullptr;
 950   }
 951   JVMFlag* flag = JVMFlag::find_flag(real_name);
 952   return flag;
 953 }
 954 
 955 bool Arguments::parse_argument(const char* arg, JVMFlagOrigin origin) {
 956   bool is_bool = false;
 957   bool bool_val = false;
 958   char c = *arg;
 959   if (c == '+' || c == '-') {
 960     is_bool = true;
 961     bool_val = (c == '+');
 962     arg++;
 963   }
 964 
 965   const char* name = arg;
 966   while (true) {
 967     c = *arg;
 968     if (isalnum(c) || (c == '_')) {
 969       ++arg;
 970     } else {
 971       break;
 972     }
 973   }
 974 
 975   size_t name_len = size_t(arg - name);
 976   if (name_len == 0) {
 977     return false;
 978   }
 979 
 980   JVMFlag* flag = find_jvm_flag(name, name_len);
 981   if (flag == nullptr) {
 982     return false;
 983   }
 984 
 985   if (is_bool) {
 986     if (*arg != 0) {
 987       // Error -- extra characters such as -XX:+BoolFlag=123
 988       return false;
 989     }
 990     return set_bool_flag(flag, bool_val, origin);
 991   }
 992 
 993   if (arg[0] == '=') {
 994     const char* value = arg + 1;
 995     if (flag->is_ccstr()) {
 996       if (flag->ccstr_accumulates()) {
 997         return append_to_string_flag(flag, value, origin);
 998       } else {
 999         return set_string_flag(flag, value, origin);
1000       }
1001     } else if (flag->is_double()) {
1002       return set_fp_numeric_flag(flag, value, origin);
1003     } else {
1004       return set_numeric_flag(flag, value, origin);
1005     }
1006   }
1007 
1008   if (arg[0] == ':' && arg[1] == '=') {
1009     // -XX:Foo:=xxx will reset the string flag to the given value.
1010     const char* value = arg + 2;
1011     return set_string_flag(flag, value, origin);
1012   }
1013 
1014   return false;
1015 }
1016 
1017 void Arguments::add_string(char*** bldarray, int* count, const char* arg) {
1018   assert(bldarray != nullptr, "illegal argument");
1019 
1020   if (arg == nullptr) {
1021     return;
1022   }
1023 
1024   int new_count = *count + 1;
1025 
1026   // expand the array and add arg to the last element
1027   if (*bldarray == nullptr) {
1028     *bldarray = NEW_C_HEAP_ARRAY(char*, new_count, mtArguments);
1029   } else {
1030     *bldarray = REALLOC_C_HEAP_ARRAY(char*, *bldarray, new_count, mtArguments);
1031   }
1032   (*bldarray)[*count] = os::strdup_check_oom(arg);
1033   *count = new_count;
1034 }
1035 
1036 void Arguments::build_jvm_args(const char* arg) {
1037   add_string(&_jvm_args_array, &_num_jvm_args, arg);
1038 }
1039 
1040 void Arguments::build_jvm_flags(const char* arg) {
1041   add_string(&_jvm_flags_array, &_num_jvm_flags, arg);
1042 }
1043 
1044 // utility function to return a string that concatenates all
1045 // strings in a given char** array
1046 const char* Arguments::build_resource_string(char** args, int count) {
1047   if (args == nullptr || count == 0) {
1048     return nullptr;
1049   }
1050   size_t length = 0;
1051   for (int i = 0; i < count; i++) {
1052     length += strlen(args[i]) + 1; // add 1 for a space or null terminating character
1053   }
1054   char* s = NEW_RESOURCE_ARRAY(char, length);
1055   char* dst = s;
1056   for (int j = 0; j < count; j++) {
1057     size_t offset = strlen(args[j]) + 1; // add 1 for a space or null terminating character
1058     jio_snprintf(dst, length, "%s ", args[j]); // jio_snprintf will replace the last space character with null character
1059     dst += offset;
1060     length -= offset;
1061   }
1062   return (const char*) s;
1063 }
1064 
1065 void Arguments::print_on(outputStream* st) {
1066   st->print_cr("VM Arguments:");
1067   if (num_jvm_flags() > 0) {
1068     st->print("jvm_flags: "); print_jvm_flags_on(st);
1069     st->cr();
1070   }
1071   if (num_jvm_args() > 0) {
1072     st->print("jvm_args: "); print_jvm_args_on(st);
1073     st->cr();
1074   }
1075   st->print_cr("java_command: %s", java_command() ? java_command() : "<unknown>");
1076   if (_java_class_path != nullptr) {
1077     char* path = _java_class_path->value();
1078     size_t len = strlen(path);
1079     st->print("java_class_path (initial): ");
1080     // Avoid using st->print_cr() because path length maybe longer than O_BUFLEN.
1081     if (len == 0) {
1082       st->print_raw_cr("<not set>");
1083     } else {
1084       st->print_raw_cr(path, len);
1085     }
1086   }
1087   st->print_cr("Launcher Type: %s", _sun_java_launcher);
1088 }
1089 
1090 void Arguments::print_summary_on(outputStream* st) {
1091   // Print the command line.  Environment variables that are helpful for
1092   // reproducing the problem are written later in the hs_err file.
1093   // flags are from setting file
1094   if (num_jvm_flags() > 0) {
1095     st->print_raw("Settings File: ");
1096     print_jvm_flags_on(st);
1097     st->cr();
1098   }
1099   // args are the command line and environment variable arguments.
1100   st->print_raw("Command Line: ");
1101   if (num_jvm_args() > 0) {
1102     print_jvm_args_on(st);
1103   }
1104   // this is the classfile and any arguments to the java program
1105   if (java_command() != nullptr) {
1106     st->print("%s", java_command());
1107   }
1108   st->cr();
1109 }
1110 
1111 void Arguments::print_jvm_flags_on(outputStream* st) {
1112   if (_num_jvm_flags > 0) {
1113     for (int i=0; i < _num_jvm_flags; i++) {
1114       st->print("%s ", _jvm_flags_array[i]);
1115     }
1116   }
1117 }
1118 
1119 void Arguments::print_jvm_args_on(outputStream* st) {
1120   if (_num_jvm_args > 0) {
1121     for (int i=0; i < _num_jvm_args; i++) {
1122       st->print("%s ", _jvm_args_array[i]);
1123     }
1124   }
1125 }
1126 
1127 bool Arguments::process_argument(const char* arg,
1128                                  jboolean ignore_unrecognized,
1129                                  JVMFlagOrigin origin) {
1130   JDK_Version since = JDK_Version();
1131 
1132   if (parse_argument(arg, origin)) {
1133     return true;
1134   }
1135 
1136   // Determine if the flag has '+', '-', or '=' characters.
1137   bool has_plus_minus = (*arg == '+' || *arg == '-');
1138   const char* const argname = has_plus_minus ? arg + 1 : arg;
1139 
1140   size_t arg_len;
1141   const char* equal_sign = strchr(argname, '=');
1142   if (equal_sign == nullptr) {
1143     arg_len = strlen(argname);
1144   } else {
1145     arg_len = equal_sign - argname;
1146   }
1147 
1148   // Only make the obsolete check for valid arguments.
1149   if (arg_len <= BUFLEN) {
1150     // Construct a string which consists only of the argument name without '+', '-', or '='.
1151     char stripped_argname[BUFLEN+1]; // +1 for '\0'
1152     jio_snprintf(stripped_argname, arg_len+1, "%s", argname); // +1 for '\0'
1153     if (is_obsolete_flag(stripped_argname, &since)) {
1154       char version[256];
1155       since.to_string(version, sizeof(version));
1156       warning("Ignoring option %s; support was removed in %s", stripped_argname, version);
1157       return true;
1158     }
1159   }
1160 
1161   // For locked flags, report a custom error message if available.
1162   // Otherwise, report the standard unrecognized VM option.
1163   const JVMFlag* found_flag = JVMFlag::find_declared_flag((const char*)argname, arg_len);
1164   if (found_flag != nullptr) {
1165     char locked_message_buf[BUFLEN];
1166     JVMFlag::MsgType msg_type = found_flag->get_locked_message(locked_message_buf, BUFLEN);
1167     if (strlen(locked_message_buf) != 0) {
1168 #ifdef PRODUCT
1169       bool mismatched = msg_type == JVMFlag::DEVELOPER_FLAG_BUT_PRODUCT_BUILD;
1170       if (ignore_unrecognized && mismatched) {
1171         return true;
1172       }
1173 #endif
1174       jio_fprintf(defaultStream::error_stream(), "%s", locked_message_buf);
1175     }
1176     if (found_flag->is_bool() && !has_plus_minus) {
1177       jio_fprintf(defaultStream::error_stream(),
1178         "Missing +/- setting for VM option '%s'\n", argname);
1179     } else if (!found_flag->is_bool() && has_plus_minus) {
1180       jio_fprintf(defaultStream::error_stream(),
1181         "Unexpected +/- setting in VM option '%s'\n", argname);
1182     } else {
1183       jio_fprintf(defaultStream::error_stream(),
1184         "Improperly specified VM option '%s'\n", argname);
1185     }
1186   } else {
1187     if (ignore_unrecognized) {
1188       return true;
1189     }
1190     jio_fprintf(defaultStream::error_stream(),
1191                 "Unrecognized VM option '%s'\n", argname);
1192     JVMFlag* fuzzy_matched = JVMFlag::fuzzy_match((const char*)argname, arg_len, true);
1193     if (fuzzy_matched != nullptr) {
1194       jio_fprintf(defaultStream::error_stream(),
1195                   "Did you mean '%s%s%s'?\n",
1196                   (fuzzy_matched->is_bool()) ? "(+/-)" : "",
1197                   fuzzy_matched->name(),
1198                   (fuzzy_matched->is_bool()) ? "" : "=<value>");
1199     }
1200   }
1201 
1202   // allow for commandline "commenting out" options like -XX:#+Verbose
1203   return arg[0] == '#';
1204 }
1205 
1206 bool Arguments::process_settings_file(const char* file_name, bool should_exist, jboolean ignore_unrecognized) {
1207   FILE* stream = os::fopen(file_name, "rb");
1208   if (stream == nullptr) {
1209     if (should_exist) {
1210       jio_fprintf(defaultStream::error_stream(),
1211                   "Could not open settings file %s\n", file_name);
1212       return false;
1213     } else {
1214       return true;
1215     }
1216   }
1217 
1218   char token[1024];
1219   int  pos = 0;
1220 
1221   bool in_white_space = true;
1222   bool in_comment     = false;
1223   bool in_quote       = false;
1224   int  quote_c        = 0;
1225   bool result         = true;
1226 
1227   int c = getc(stream);
1228   while(c != EOF && pos < (int)(sizeof(token)-1)) {
1229     if (in_white_space) {
1230       if (in_comment) {
1231         if (c == '\n') in_comment = false;
1232       } else {
1233         if (c == '#') in_comment = true;
1234         else if (!isspace((unsigned char) c)) {
1235           in_white_space = false;
1236           token[pos++] = checked_cast<char>(c);
1237         }
1238       }
1239     } else {
1240       if (c == '\n' || (!in_quote && isspace((unsigned char) c))) {
1241         // token ends at newline, or at unquoted whitespace
1242         // this allows a way to include spaces in string-valued options
1243         token[pos] = '\0';
1244         logOption(token);
1245         result &= process_argument(token, ignore_unrecognized, JVMFlagOrigin::CONFIG_FILE);
1246         build_jvm_flags(token);
1247         pos = 0;
1248         in_white_space = true;
1249         in_quote = false;
1250       } else if (!in_quote && (c == '\'' || c == '"')) {
1251         in_quote = true;
1252         quote_c = c;
1253       } else if (in_quote && (c == quote_c)) {
1254         in_quote = false;
1255       } else {
1256         token[pos++] = checked_cast<char>(c);
1257       }
1258     }
1259     c = getc(stream);
1260   }
1261   if (pos > 0) {
1262     token[pos] = '\0';
1263     result &= process_argument(token, ignore_unrecognized, JVMFlagOrigin::CONFIG_FILE);
1264     build_jvm_flags(token);
1265   }
1266   fclose(stream);
1267   return result;
1268 }
1269 
1270 //=============================================================================================================
1271 // Parsing of properties (-D)
1272 
1273 const char* Arguments::get_property(const char* key) {
1274   return PropertyList_get_value(system_properties(), key);
1275 }
1276 
1277 bool Arguments::add_property(const char* prop, PropertyWriteable writeable, PropertyInternal internal) {
1278   const char* eq = strchr(prop, '=');
1279   const char* key;
1280   const char* value = "";
1281 
1282   if (eq == nullptr) {
1283     // property doesn't have a value, thus use passed string
1284     key = prop;
1285   } else {
1286     // property have a value, thus extract it and save to the
1287     // allocated string
1288     size_t key_len = eq - prop;
1289     char* tmp_key = AllocateHeap(key_len + 1, mtArguments);
1290 
1291     jio_snprintf(tmp_key, key_len + 1, "%s", prop);
1292     key = tmp_key;
1293 
1294     value = &prop[key_len + 1];
1295   }
1296 
1297   if (internal == ExternalProperty) {
1298     CDSConfig::check_incompatible_property(key, value);
1299   }
1300 
1301   if (strcmp(key, "java.compiler") == 0) {
1302     // we no longer support java.compiler system property, log a warning and let it get
1303     // passed to Java, like any other system property
1304     if (strlen(value) == 0 || strcasecmp(value, "NONE") == 0) {
1305         // for applications using NONE or empty value, log a more informative message
1306         warning("The java.compiler system property is obsolete and no longer supported, use -Xint");
1307     } else {
1308         warning("The java.compiler system property is obsolete and no longer supported.");
1309     }
1310   } else if (strcmp(key, "sun.boot.library.path") == 0) {
1311     // append is true, writable is true, internal is false
1312     PropertyList_unique_add(&_system_properties, key, value, AppendProperty,
1313                             WriteableProperty, ExternalProperty);
1314   } else {
1315     if (strcmp(key, "sun.java.command") == 0) {
1316       char *old_java_command = _java_command;
1317       _java_command = os::strdup_check_oom(value, mtArguments);
1318       if (old_java_command != nullptr) {
1319         os::free(old_java_command);
1320       }
1321     } else if (strcmp(key, "java.vendor.url.bug") == 0) {
1322       // If this property is set on the command line then its value will be
1323       // displayed in VM error logs as the URL at which to submit such logs.
1324       // Normally the URL displayed in error logs is different from the value
1325       // of this system property, so a different property should have been
1326       // used here, but we leave this as-is in case someone depends upon it.
1327       const char* old_java_vendor_url_bug = _java_vendor_url_bug;
1328       // save it in _java_vendor_url_bug, so JVM fatal error handler can access
1329       // its value without going through the property list or making a Java call.
1330       _java_vendor_url_bug = os::strdup_check_oom(value, mtArguments);
1331       if (old_java_vendor_url_bug != nullptr) {
1332         os::free((void *)old_java_vendor_url_bug);
1333       }
1334     }
1335 
1336     // Create new property and add at the end of the list
1337     PropertyList_unique_add(&_system_properties, key, value, AddProperty, writeable, internal);
1338   }
1339 
1340   if (key != prop) {
1341     // SystemProperty copy passed value, thus free previously allocated
1342     // memory
1343     FreeHeap((void *)key);
1344   }
1345 
1346   return true;
1347 }
1348 
1349 //===========================================================================================================
1350 // Setting int/mixed/comp mode flags
1351 
1352 void Arguments::set_mode_flags(Mode mode) {
1353   // Set up default values for all flags.
1354   // If you add a flag to any of the branches below,
1355   // add a default value for it here.
1356   _mode                      = mode;
1357 
1358   // Ensure Agent_OnLoad has the correct initial values.
1359   // This may not be the final mode; mode may change later in onload phase.
1360   PropertyList_unique_add(&_system_properties, "java.vm.info",
1361                           VM_Version::vm_info_string(), AddProperty, UnwriteableProperty, ExternalProperty);
1362 
1363   UseInterpreter             = true;
1364   UseCompiler                = true;
1365   UseLoopCounter             = true;
1366 
1367   // Default values may be platform/compiler dependent -
1368   // use the saved values
1369   ClipInlining               = Arguments::_ClipInlining;
1370   AlwaysCompileLoopMethods   = Arguments::_AlwaysCompileLoopMethods;
1371   UseOnStackReplacement      = Arguments::_UseOnStackReplacement;
1372   BackgroundCompilation      = Arguments::_BackgroundCompilation;
1373 
1374   // Change from defaults based on mode
1375   switch (mode) {
1376   default:
1377     ShouldNotReachHere();
1378     break;
1379   case _int:
1380     UseCompiler              = false;
1381     UseLoopCounter           = false;
1382     AlwaysCompileLoopMethods = false;
1383     UseOnStackReplacement    = false;
1384     break;
1385   case _mixed:
1386     // same as default
1387     break;
1388   case _comp:
1389     UseInterpreter           = false;
1390     BackgroundCompilation    = false;
1391     ClipInlining             = false;
1392     break;
1393   }
1394 }
1395 
1396 // Conflict: required to use shared spaces (-Xshare:on), but
1397 // incompatible command line options were chosen.
1398 void Arguments::no_shared_spaces(const char* message) {
1399   if (RequireSharedSpaces) {
1400     aot_log_error(aot)("%s is incompatible with other specified options.",
1401                    CDSConfig::new_aot_flags_used() ? "AOT cache" : "CDS");
1402     if (CDSConfig::new_aot_flags_used()) {
1403       vm_exit_during_initialization("Unable to use AOT cache", message);
1404     } else {
1405       vm_exit_during_initialization("Unable to use shared archive", message);
1406     }
1407   } else {
1408     if (CDSConfig::new_aot_flags_used()) {
1409       log_warning(aot)("Unable to use AOT cache: %s", message);
1410     } else {
1411       aot_log_info(aot)("Unable to use shared archive: %s", message);
1412     }
1413     UseSharedSpaces = false;
1414   }
1415 }
1416 
1417 static void set_object_alignment() {
1418   // Object alignment.
1419   assert(is_power_of_2(ObjectAlignmentInBytes), "ObjectAlignmentInBytes must be power of 2");
1420   MinObjAlignmentInBytes     = ObjectAlignmentInBytes;
1421   assert(MinObjAlignmentInBytes >= HeapWordsPerLong * HeapWordSize, "ObjectAlignmentInBytes value is too small");
1422   MinObjAlignment            = MinObjAlignmentInBytes / HeapWordSize;
1423   assert(MinObjAlignmentInBytes == MinObjAlignment * HeapWordSize, "ObjectAlignmentInBytes value is incorrect");
1424   MinObjAlignmentInBytesMask = MinObjAlignmentInBytes - 1;
1425 
1426   LogMinObjAlignmentInBytes  = exact_log2(ObjectAlignmentInBytes);
1427   LogMinObjAlignment         = LogMinObjAlignmentInBytes - LogHeapWordSize;
1428 
1429   // Oop encoding heap max
1430   OopEncodingHeapMax = (uint64_t(max_juint) + 1) << LogMinObjAlignmentInBytes;
1431 }
1432 
1433 size_t Arguments::max_heap_for_compressed_oops() {
1434   // Avoid sign flip.
1435   assert(OopEncodingHeapMax > (uint64_t)os::vm_page_size(), "Unusual page size");
1436   // We need to fit both the null page and the heap into the memory budget, while
1437   // keeping alignment constraints of the heap. To guarantee the latter, as the
1438   // null page is located before the heap, we pad the null page to the conservative
1439   // maximum alignment that the GC may ever impose upon the heap.
1440   size_t displacement_due_to_null_page = align_up(os::vm_page_size(),
1441                                                   _conservative_max_heap_alignment);
1442 
1443   LP64_ONLY(return OopEncodingHeapMax - displacement_due_to_null_page);
1444   NOT_LP64(ShouldNotReachHere(); return 0);
1445 }
1446 
1447 void Arguments::set_use_compressed_oops() {
1448 #ifdef _LP64
1449   // MaxHeapSize is not set up properly at this point, but
1450   // the only value that can override MaxHeapSize if we are
1451   // to use UseCompressedOops are InitialHeapSize and MinHeapSize.
1452   size_t max_heap_size = MAX3(MaxHeapSize, InitialHeapSize, MinHeapSize);
1453 
1454   if (max_heap_size <= max_heap_for_compressed_oops()) {
1455     if (FLAG_IS_DEFAULT(UseCompressedOops)) {
1456       FLAG_SET_ERGO(UseCompressedOops, true);
1457     }
1458   } else {
1459     if (UseCompressedOops && !FLAG_IS_DEFAULT(UseCompressedOops)) {
1460       warning("Max heap size too large for Compressed Oops");
1461       FLAG_SET_DEFAULT(UseCompressedOops, false);
1462     }
1463   }
1464 #endif // _LP64
1465 }
1466 
1467 void Arguments::set_conservative_max_heap_alignment() {
1468   // The conservative maximum required alignment for the heap is the maximum of
1469   // the alignments imposed by several sources: any requirements from the heap
1470   // itself and the maximum page size we may run the VM with.
1471   size_t heap_alignment = GCConfig::arguments()->conservative_max_heap_alignment();
1472   _conservative_max_heap_alignment = MAX4(heap_alignment,
1473                                           os::vm_allocation_granularity(),
1474                                           os::max_page_size(),
1475                                           GCArguments::compute_heap_alignment());
1476 }
1477 
1478 jint Arguments::set_ergonomics_flags() {
1479   GCConfig::initialize();
1480 
1481   set_conservative_max_heap_alignment();
1482 
1483 #ifdef _LP64
1484   set_use_compressed_oops();
1485 
1486   // Also checks that certain machines are slower with compressed oops
1487   // in vm_version initialization code.
1488 #endif // _LP64
1489 
1490   return JNI_OK;
1491 }
1492 
1493 size_t Arguments::limit_heap_by_allocatable_memory(size_t limit) {
1494   // The AggressiveHeap check is a temporary workaround to avoid calling
1495   // GCarguments::heap_virtual_to_physical_ratio() before a GC has been
1496   // selected. This works because AggressiveHeap implies UseParallelGC
1497   // where we know the ratio will be 1. Once the AggressiveHeap option is
1498   // removed, this can be cleaned up.
1499   size_t heap_virtual_to_physical_ratio = (AggressiveHeap ? 1 : GCConfig::arguments()->heap_virtual_to_physical_ratio());
1500   size_t fraction = MaxVirtMemFraction * heap_virtual_to_physical_ratio;
1501   size_t max_allocatable = os::commit_memory_limit();
1502 
1503   return MIN2(limit, max_allocatable / fraction);
1504 }
1505 
1506 // Use static initialization to get the default before parsing
1507 static const size_t DefaultHeapBaseMinAddress = HeapBaseMinAddress;
1508 
1509 void Arguments::set_heap_size() {
1510   julong phys_mem;
1511 
1512   // If the user specified one of these options, they
1513   // want specific memory sizing so do not limit memory
1514   // based on compressed oops addressability.
1515   // Also, memory limits will be calculated based on
1516   // available os physical memory, not our MaxRAM limit,
1517   // unless MaxRAM is also specified.
1518   bool override_coop_limit = (!FLAG_IS_DEFAULT(MaxRAMPercentage) ||
1519                            !FLAG_IS_DEFAULT(MinRAMPercentage) ||
1520                            !FLAG_IS_DEFAULT(InitialRAMPercentage) ||
1521                            !FLAG_IS_DEFAULT(MaxRAM));
1522   if (override_coop_limit) {
1523     if (FLAG_IS_DEFAULT(MaxRAM)) {
1524       phys_mem = static_cast<julong>(os::physical_memory());
1525       FLAG_SET_ERGO(MaxRAM, (uint64_t)phys_mem);
1526     } else {
1527       phys_mem = (julong)MaxRAM;
1528     }
1529   } else {
1530     phys_mem = FLAG_IS_DEFAULT(MaxRAM) ? MIN2(static_cast<julong>(os::physical_memory()), (julong)MaxRAM)
1531                                        : (julong)MaxRAM;
1532   }
1533 
1534   // If the maximum heap size has not been set with -Xmx,
1535   // then set it as fraction of the size of physical memory,
1536   // respecting the maximum and minimum sizes of the heap.
1537   if (FLAG_IS_DEFAULT(MaxHeapSize)) {
1538     julong reasonable_max = (julong)(((double)phys_mem * MaxRAMPercentage) / 100);
1539     const julong reasonable_min = (julong)(((double)phys_mem * MinRAMPercentage) / 100);
1540     if (reasonable_min < MaxHeapSize) {
1541       // Small physical memory, so use a minimum fraction of it for the heap
1542       reasonable_max = reasonable_min;
1543     } else {
1544       // Not-small physical memory, so require a heap at least
1545       // as large as MaxHeapSize
1546       reasonable_max = MAX2(reasonable_max, (julong)MaxHeapSize);
1547     }
1548 
1549     if (!FLAG_IS_DEFAULT(ErgoHeapSizeLimit) && ErgoHeapSizeLimit != 0) {
1550       // Limit the heap size to ErgoHeapSizeLimit
1551       reasonable_max = MIN2(reasonable_max, (julong)ErgoHeapSizeLimit);
1552     }
1553 
1554     reasonable_max = limit_heap_by_allocatable_memory(reasonable_max);
1555 
1556     if (!FLAG_IS_DEFAULT(InitialHeapSize)) {
1557       // An initial heap size was specified on the command line,
1558       // so be sure that the maximum size is consistent.  Done
1559       // after call to limit_heap_by_allocatable_memory because that
1560       // method might reduce the allocation size.
1561       reasonable_max = MAX2(reasonable_max, (julong)InitialHeapSize);
1562     } else if (!FLAG_IS_DEFAULT(MinHeapSize)) {
1563       reasonable_max = MAX2(reasonable_max, (julong)MinHeapSize);
1564     }
1565 
1566 #ifdef _LP64
1567     if (UseCompressedOops || UseCompressedClassPointers) {
1568       // HeapBaseMinAddress can be greater than default but not less than.
1569       if (!FLAG_IS_DEFAULT(HeapBaseMinAddress)) {
1570         if (HeapBaseMinAddress < DefaultHeapBaseMinAddress) {
1571           // matches compressed oops printing flags
1572           log_debug(gc, heap, coops)("HeapBaseMinAddress must be at least %zu"
1573                                      " (%zuG) which is greater than value given %zu",
1574                                      DefaultHeapBaseMinAddress,
1575                                      DefaultHeapBaseMinAddress/G,
1576                                      HeapBaseMinAddress);
1577           FLAG_SET_ERGO(HeapBaseMinAddress, DefaultHeapBaseMinAddress);
1578         }
1579       }
1580     }
1581     if (UseCompressedOops) {
1582       // Limit the heap size to the maximum possible when using compressed oops
1583       julong max_coop_heap = (julong)max_heap_for_compressed_oops();
1584 
1585       if (HeapBaseMinAddress + MaxHeapSize < max_coop_heap) {
1586         // Heap should be above HeapBaseMinAddress to get zero based compressed oops
1587         // but it should be not less than default MaxHeapSize.
1588         max_coop_heap -= HeapBaseMinAddress;
1589       }
1590 
1591       // If user specified flags prioritizing os physical
1592       // memory limits, then disable compressed oops if
1593       // limits exceed max_coop_heap and UseCompressedOops
1594       // was not specified.
1595       if (reasonable_max > max_coop_heap) {
1596         if (FLAG_IS_ERGO(UseCompressedOops) && override_coop_limit) {
1597           aot_log_info(aot)("UseCompressedOops disabled due to"
1598             " max heap %zu > compressed oop heap %zu. "
1599             "Please check the setting of MaxRAMPercentage %5.2f."
1600             ,(size_t)reasonable_max, (size_t)max_coop_heap, MaxRAMPercentage);
1601           FLAG_SET_ERGO(UseCompressedOops, false);
1602         } else {
1603           reasonable_max = MIN2(reasonable_max, max_coop_heap);
1604         }
1605       }
1606     }
1607 #endif // _LP64
1608 
1609     log_trace(gc, heap)("  Maximum heap size %zu", (size_t) reasonable_max);
1610     FLAG_SET_ERGO(MaxHeapSize, (size_t)reasonable_max);
1611   }
1612 
1613   // If the minimum or initial heap_size have not been set or requested to be set
1614   // ergonomically, set them accordingly.
1615   if (InitialHeapSize == 0 || MinHeapSize == 0) {
1616     julong reasonable_minimum = (julong)(OldSize + NewSize);
1617 
1618     reasonable_minimum = MIN2(reasonable_minimum, (julong)MaxHeapSize);
1619 
1620     reasonable_minimum = limit_heap_by_allocatable_memory(reasonable_minimum);
1621 
1622     if (InitialHeapSize == 0) {
1623       julong reasonable_initial = (julong)(((double)phys_mem * InitialRAMPercentage) / 100);
1624       reasonable_initial = limit_heap_by_allocatable_memory(reasonable_initial);
1625 
1626       reasonable_initial = MAX3(reasonable_initial, reasonable_minimum, (julong)MinHeapSize);
1627       reasonable_initial = MIN2(reasonable_initial, (julong)MaxHeapSize);
1628 
1629       FLAG_SET_ERGO(InitialHeapSize, (size_t)reasonable_initial);
1630       log_trace(gc, heap)("  Initial heap size %zu", InitialHeapSize);
1631     }
1632     // If the minimum heap size has not been set (via -Xms or -XX:MinHeapSize),
1633     // synchronize with InitialHeapSize to avoid errors with the default value.
1634     if (MinHeapSize == 0) {
1635       FLAG_SET_ERGO(MinHeapSize, MIN2((size_t)reasonable_minimum, InitialHeapSize));
1636       log_trace(gc, heap)("  Minimum heap size %zu", MinHeapSize);
1637     }
1638   }
1639 }
1640 
1641 // This option inspects the machine and attempts to set various
1642 // parameters to be optimal for long-running, memory allocation
1643 // intensive jobs.  It is intended for machines with large
1644 // amounts of cpu and memory.
1645 jint Arguments::set_aggressive_heap_flags() {
1646   // initHeapSize is needed since _initial_heap_size is 4 bytes on a 32 bit
1647   // VM, but we may not be able to represent the total physical memory
1648   // available (like having 8gb of memory on a box but using a 32bit VM).
1649   // Thus, we need to make sure we're using a julong for intermediate
1650   // calculations.
1651   julong initHeapSize;
1652   size_t phys_mem = os::physical_memory();
1653   julong total_memory = static_cast<julong>(phys_mem);
1654 
1655   if (total_memory < (julong) 256 * M) {
1656     jio_fprintf(defaultStream::error_stream(),
1657             "You need at least 256mb of memory to use -XX:+AggressiveHeap\n");
1658     vm_exit(1);
1659   }
1660 
1661   // The heap size is half of available memory, or (at most)
1662   // all of possible memory less 160mb (leaving room for the OS
1663   // when using ISM).  This is the maximum; because adaptive sizing
1664   // is turned on below, the actual space used may be smaller.
1665 
1666   initHeapSize = MIN2(total_memory / (julong) 2,
1667           total_memory - (julong) 160 * M);
1668 
1669   initHeapSize = limit_heap_by_allocatable_memory(initHeapSize);
1670 
1671   if (FLAG_IS_DEFAULT(MaxHeapSize)) {
1672     if (FLAG_SET_CMDLINE(MaxHeapSize, initHeapSize) != JVMFlag::SUCCESS) {
1673       return JNI_EINVAL;
1674     }
1675     if (FLAG_SET_CMDLINE(InitialHeapSize, initHeapSize) != JVMFlag::SUCCESS) {
1676       return JNI_EINVAL;
1677     }
1678     if (FLAG_SET_CMDLINE(MinHeapSize, initHeapSize) != JVMFlag::SUCCESS) {
1679       return JNI_EINVAL;
1680     }
1681   }
1682   if (FLAG_IS_DEFAULT(NewSize)) {
1683     // Make the young generation 3/8ths of the total heap.
1684     if (FLAG_SET_CMDLINE(NewSize,
1685             ((julong) MaxHeapSize / (julong) 8) * (julong) 3) != JVMFlag::SUCCESS) {
1686       return JNI_EINVAL;
1687     }
1688     if (FLAG_SET_CMDLINE(MaxNewSize, NewSize) != JVMFlag::SUCCESS) {
1689       return JNI_EINVAL;
1690     }
1691   }
1692 
1693 #if !defined(_ALLBSD_SOURCE) && !defined(AIX)  // UseLargePages is not yet supported on BSD and AIX.
1694   FLAG_SET_DEFAULT(UseLargePages, true);
1695 #endif
1696 
1697   // Increase some data structure sizes for efficiency
1698   if (FLAG_SET_CMDLINE(ResizeTLAB, false) != JVMFlag::SUCCESS) {
1699     return JNI_EINVAL;
1700   }
1701   if (FLAG_SET_CMDLINE(TLABSize, 256 * K) != JVMFlag::SUCCESS) {
1702     return JNI_EINVAL;
1703   }
1704 
1705   // See the OldPLABSize comment below, but replace 'after promotion'
1706   // with 'after copying'.  YoungPLABSize is the size of the survivor
1707   // space per-gc-thread buffers.  The default is 4kw.
1708   if (FLAG_SET_CMDLINE(YoungPLABSize, 256 * K) != JVMFlag::SUCCESS) { // Note: this is in words
1709     return JNI_EINVAL;
1710   }
1711 
1712   // OldPLABSize is the size of the buffers in the old gen that
1713   // UseParallelGC uses to promote live data that doesn't fit in the
1714   // survivor spaces.  At any given time, there's one for each gc thread.
1715   // The default size is 1kw. These buffers are rarely used, since the
1716   // survivor spaces are usually big enough.  For specjbb, however, there
1717   // are occasions when there's lots of live data in the young gen
1718   // and we end up promoting some of it.  We don't have a definite
1719   // explanation for why bumping OldPLABSize helps, but the theory
1720   // is that a bigger PLAB results in retaining something like the
1721   // original allocation order after promotion, which improves mutator
1722   // locality.  A minor effect may be that larger PLABs reduce the
1723   // number of PLAB allocation events during gc.  The value of 8kw
1724   // was arrived at by experimenting with specjbb.
1725   if (FLAG_SET_CMDLINE(OldPLABSize, 8 * K) != JVMFlag::SUCCESS) { // Note: this is in words
1726     return JNI_EINVAL;
1727   }
1728 
1729   // Enable parallel GC and adaptive generation sizing
1730   if (FLAG_SET_CMDLINE(UseParallelGC, true) != JVMFlag::SUCCESS) {
1731     return JNI_EINVAL;
1732   }
1733 
1734   // Encourage steady state memory management
1735   if (FLAG_SET_CMDLINE(ThresholdTolerance, 100) != JVMFlag::SUCCESS) {
1736     return JNI_EINVAL;
1737   }
1738 
1739   return JNI_OK;
1740 }
1741 
1742 // This must be called after ergonomics.
1743 void Arguments::set_bytecode_flags() {
1744   if (!RewriteBytecodes) {
1745     FLAG_SET_DEFAULT(RewriteFrequentPairs, false);
1746   }
1747 }
1748 
1749 // Aggressive optimization flags
1750 jint Arguments::set_aggressive_opts_flags() {
1751 #ifdef COMPILER2
1752   if (AggressiveUnboxing) {
1753     if (FLAG_IS_DEFAULT(EliminateAutoBox)) {
1754       FLAG_SET_DEFAULT(EliminateAutoBox, true);
1755     } else if (!EliminateAutoBox) {
1756       // warning("AggressiveUnboxing is disabled because EliminateAutoBox is disabled");
1757       AggressiveUnboxing = false;
1758     }
1759     if (FLAG_IS_DEFAULT(DoEscapeAnalysis)) {
1760       FLAG_SET_DEFAULT(DoEscapeAnalysis, true);
1761     } else if (!DoEscapeAnalysis) {
1762       // warning("AggressiveUnboxing is disabled because DoEscapeAnalysis is disabled");
1763       AggressiveUnboxing = false;
1764     }
1765   }
1766   if (!FLAG_IS_DEFAULT(AutoBoxCacheMax)) {
1767     if (FLAG_IS_DEFAULT(EliminateAutoBox)) {
1768       FLAG_SET_DEFAULT(EliminateAutoBox, true);
1769     }
1770     // Feed the cache size setting into the JDK
1771     char buffer[1024];
1772     jio_snprintf(buffer, 1024, "java.lang.Integer.IntegerCache.high=%zd", AutoBoxCacheMax);
1773     if (!add_property(buffer)) {
1774       return JNI_ENOMEM;
1775     }
1776   }
1777 #endif
1778 
1779   return JNI_OK;
1780 }
1781 
1782 //===========================================================================================================
1783 
1784 void Arguments::process_java_launcher_argument(const char* launcher, void* extra_info) {
1785   if (_sun_java_launcher != _default_java_launcher) {
1786     os::free(const_cast<char*>(_sun_java_launcher));
1787   }
1788   _sun_java_launcher = os::strdup_check_oom(launcher);
1789 }
1790 
1791 bool Arguments::created_by_java_launcher() {
1792   assert(_sun_java_launcher != nullptr, "property must have value");
1793   return strcmp(DEFAULT_JAVA_LAUNCHER, _sun_java_launcher) != 0;
1794 }
1795 
1796 bool Arguments::executing_unit_tests() {
1797   return _executing_unit_tests;
1798 }
1799 
1800 //===========================================================================================================
1801 // Parsing of main arguments
1802 
1803 static unsigned int addreads_count = 0;
1804 static unsigned int addexports_count = 0;
1805 static unsigned int addopens_count = 0;
1806 static unsigned int patch_mod_count = 0;
1807 static unsigned int enable_native_access_count = 0;
1808 static bool patch_mod_javabase = false;
1809 
1810 // Check the consistency of vm_init_args
1811 bool Arguments::check_vm_args_consistency() {
1812   // This may modify compiler flags. Must be called before CompilerConfig::check_args_consistency()
1813   if (!CDSConfig::check_vm_args_consistency(patch_mod_javabase, mode_flag_cmd_line)) {
1814     return false;
1815   }
1816 
1817   // Method for adding checks for flag consistency.
1818   // The intent is to warn the user of all possible conflicts,
1819   // before returning an error.
1820   // Note: Needs platform-dependent factoring.
1821   bool status = true;
1822 
1823   if (TLABRefillWasteFraction == 0) {
1824     jio_fprintf(defaultStream::error_stream(),
1825                 "TLABRefillWasteFraction should be a denominator, "
1826                 "not %zu\n",
1827                 TLABRefillWasteFraction);
1828     status = false;
1829   }
1830 
1831   status = CompilerConfig::check_args_consistency(status);
1832 #if INCLUDE_JVMCI
1833   if (status && EnableJVMCI) {
1834     // Add the JVMCI module if not using libjvmci or EnableJVMCI
1835     // was explicitly set on the command line or in the jimage.
1836     if ((!UseJVMCINativeLibrary || FLAG_IS_CMDLINE(EnableJVMCI) || FLAG_IS_JIMAGE_RESOURCE(EnableJVMCI)) && ClassLoader::is_module_observable("jdk.internal.vm.ci") && !_jvmci_module_added) {
1837       if (!create_numbered_module_property("jdk.module.addmods", "jdk.internal.vm.ci", _addmods_count++)) {
1838         return false;
1839       }
1840     }
1841   }
1842 #endif
1843 
1844 #if INCLUDE_JFR
1845   if (status && (FlightRecorderOptions || StartFlightRecording)) {
1846     if (!create_numbered_module_property("jdk.module.addmods", "jdk.jfr", _addmods_count++)) {
1847       return false;
1848     }
1849   }
1850 #endif
1851 
1852 #ifndef SUPPORT_RESERVED_STACK_AREA
1853   if (StackReservedPages != 0) {
1854     FLAG_SET_CMDLINE(StackReservedPages, 0);
1855     warning("Reserved Stack Area not supported on this platform");
1856   }
1857 #endif
1858 
1859   return status;
1860 }
1861 
1862 bool Arguments::is_bad_option(const JavaVMOption* option, jboolean ignore,
1863   const char* option_type) {
1864   if (ignore) return false;
1865 
1866   const char* spacer = " ";
1867   if (option_type == nullptr) {
1868     option_type = ++spacer; // Set both to the empty string.
1869   }
1870 
1871   jio_fprintf(defaultStream::error_stream(),
1872               "Unrecognized %s%soption: %s\n", option_type, spacer,
1873               option->optionString);
1874   return true;
1875 }
1876 
1877 static const char* user_assertion_options[] = {
1878   "-da", "-ea", "-disableassertions", "-enableassertions", nullptr
1879 };
1880 
1881 static const char* system_assertion_options[] = {
1882   "-dsa", "-esa", "-disablesystemassertions", "-enablesystemassertions", nullptr
1883 };
1884 
1885 bool Arguments::parse_uint(const char* value,
1886                            uint* uint_arg,
1887                            uint min_size) {
1888   uint n;
1889   if (!parse_integer(value, &n)) {
1890     return false;
1891   }
1892   if (n >= min_size) {
1893     *uint_arg = n;
1894     return true;
1895   } else {
1896     return false;
1897   }
1898 }
1899 
1900 bool Arguments::create_module_property(const char* prop_name, const char* prop_value, PropertyInternal internal) {
1901   assert(is_internal_module_property(prop_name), "unknown module property: '%s'", prop_name);
1902   CDSConfig::check_internal_module_property(prop_name, prop_value);
1903   size_t prop_len = strlen(prop_name) + strlen(prop_value) + 2;
1904   char* property = AllocateHeap(prop_len, mtArguments);
1905   int ret = jio_snprintf(property, prop_len, "%s=%s", prop_name, prop_value);
1906   if (ret < 0 || ret >= (int)prop_len) {
1907     FreeHeap(property);
1908     return false;
1909   }
1910   // These are not strictly writeable properties as they cannot be set via -Dprop=val. But that
1911   // is enforced by checking is_internal_module_property(). We need the property to be writeable so
1912   // that multiple occurrences of the associated flag just causes the existing property value to be
1913   // replaced ("last option wins"). Otherwise we would need to keep track of the flags and only convert
1914   // to a property after we have finished flag processing.
1915   bool added = add_property(property, WriteableProperty, internal);
1916   FreeHeap(property);
1917   return added;
1918 }
1919 
1920 bool Arguments::create_numbered_module_property(const char* prop_base_name, const char* prop_value, unsigned int count) {
1921   assert(is_internal_module_property(prop_base_name), "unknown module property: '%s'", prop_base_name);
1922   CDSConfig::check_internal_module_property(prop_base_name, prop_value);
1923   const unsigned int props_count_limit = 1000;
1924   const int max_digits = 3;
1925   const int extra_symbols_count = 3; // includes '.', '=', '\0'
1926 
1927   // Make sure count is < props_count_limit. Otherwise, memory allocation will be too small.
1928   if (count < props_count_limit) {
1929     size_t prop_len = strlen(prop_base_name) + strlen(prop_value) + max_digits + extra_symbols_count;
1930     char* property = AllocateHeap(prop_len, mtArguments);
1931     int ret = jio_snprintf(property, prop_len, "%s.%d=%s", prop_base_name, count, prop_value);
1932     if (ret < 0 || ret >= (int)prop_len) {
1933       FreeHeap(property);
1934       jio_fprintf(defaultStream::error_stream(), "Failed to create property %s.%d=%s\n", prop_base_name, count, prop_value);
1935       return false;
1936     }
1937     bool added = add_property(property, UnwriteableProperty, InternalProperty);
1938     FreeHeap(property);
1939     return added;
1940   }
1941 
1942   jio_fprintf(defaultStream::error_stream(), "Property count limit exceeded: %s, limit=%d\n", prop_base_name, props_count_limit);
1943   return false;
1944 }
1945 
1946 Arguments::ArgsRange Arguments::parse_memory_size(const char* s,
1947                                                   julong* long_arg,
1948                                                   julong min_size,
1949                                                   julong max_size) {
1950   if (!parse_integer(s, long_arg)) return arg_unreadable;
1951   return check_memory_size(*long_arg, min_size, max_size);
1952 }
1953 
1954 jint Arguments::parse_vm_init_args(GrowableArrayCHeap<VMInitArgsGroup, mtArguments>* all_args) {
1955   // Save default settings for some mode flags
1956   Arguments::_AlwaysCompileLoopMethods = AlwaysCompileLoopMethods;
1957   Arguments::_UseOnStackReplacement    = UseOnStackReplacement;
1958   Arguments::_ClipInlining             = ClipInlining;
1959   Arguments::_BackgroundCompilation    = BackgroundCompilation;
1960 
1961   // Remember the default value of SharedBaseAddress.
1962   Arguments::_default_SharedBaseAddress = SharedBaseAddress;
1963 
1964   // Setup flags for mixed which is the default
1965   set_mode_flags(_mixed);
1966 
1967   jint result;
1968   for (int i = 0; i < all_args->length(); i++) {
1969     result = parse_each_vm_init_arg(all_args->at(i)._args, all_args->at(i)._origin);
1970     if (result != JNI_OK) {
1971       return result;
1972     }
1973   }
1974 
1975   // Disable CDS for exploded image
1976   if (!has_jimage()) {
1977     no_shared_spaces("CDS disabled on exploded JDK");
1978   }
1979 
1980   // We need to ensure processor and memory resources have been properly
1981   // configured - which may rely on arguments we just processed - before
1982   // doing the final argument processing. Any argument processing that
1983   // needs to know about processor and memory resources must occur after
1984   // this point.
1985 
1986   os::init_container_support();
1987 
1988   SystemMemoryBarrier::initialize();
1989 
1990   // Do final processing now that all arguments have been parsed
1991   result = finalize_vm_init_args();
1992   if (result != JNI_OK) {
1993     return result;
1994   }
1995 
1996   return JNI_OK;
1997 }
1998 
1999 #if !INCLUDE_JVMTI || INCLUDE_CDS
2000 // Checks if name in command-line argument -agent{lib,path}:name[=options]
2001 // represents a valid JDWP agent.  is_path==true denotes that we
2002 // are dealing with -agentpath (case where name is a path), otherwise with
2003 // -agentlib
2004 static bool valid_jdwp_agent(char *name, bool is_path) {
2005   char *_name;
2006   const char *_jdwp = "jdwp";
2007   size_t _len_jdwp, _len_prefix;
2008 
2009   if (is_path) {
2010     if ((_name = strrchr(name, (int) *os::file_separator())) == nullptr) {
2011       return false;
2012     }
2013 
2014     _name++;  // skip past last path separator
2015     _len_prefix = strlen(JNI_LIB_PREFIX);
2016 
2017     if (strncmp(_name, JNI_LIB_PREFIX, _len_prefix) != 0) {
2018       return false;
2019     }
2020 
2021     _name += _len_prefix;
2022     _len_jdwp = strlen(_jdwp);
2023 
2024     if (strncmp(_name, _jdwp, _len_jdwp) == 0) {
2025       _name += _len_jdwp;
2026     }
2027     else {
2028       return false;
2029     }
2030 
2031     if (strcmp(_name, JNI_LIB_SUFFIX) != 0) {
2032       return false;
2033     }
2034 
2035     return true;
2036   }
2037 
2038   if (strcmp(name, _jdwp) == 0) {
2039     return true;
2040   }
2041 
2042   return false;
2043 }
2044 #endif
2045 
2046 int Arguments::process_patch_mod_option(const char* patch_mod_tail) {
2047   // --patch-module=<module>=<file>(<pathsep><file>)*
2048   assert(patch_mod_tail != nullptr, "Unexpected null patch-module value");
2049   // Find the equal sign between the module name and the path specification
2050   const char* module_equal = strchr(patch_mod_tail, '=');
2051   if (module_equal == nullptr) {
2052     jio_fprintf(defaultStream::output_stream(), "Missing '=' in --patch-module specification\n");
2053     return JNI_ERR;
2054   } else {
2055     // Pick out the module name
2056     size_t module_len = module_equal - patch_mod_tail;
2057     char* module_name = NEW_C_HEAP_ARRAY_RETURN_NULL(char, module_len+1, mtArguments);
2058     if (module_name != nullptr) {
2059       memcpy(module_name, patch_mod_tail, module_len);
2060       *(module_name + module_len) = '\0';
2061       // The path piece begins one past the module_equal sign
2062       add_patch_mod_prefix(module_name, module_equal + 1);
2063       FREE_C_HEAP_ARRAY(char, module_name);
2064       if (!create_numbered_module_property("jdk.module.patch", patch_mod_tail, patch_mod_count++)) {
2065         return JNI_ENOMEM;
2066       }
2067     } else {
2068       return JNI_ENOMEM;
2069     }
2070   }
2071   return JNI_OK;
2072 }
2073 
2074 // Parse -Xss memory string parameter and convert to ThreadStackSize in K.
2075 jint Arguments::parse_xss(const JavaVMOption* option, const char* tail, intx* out_ThreadStackSize) {
2076   // The min and max sizes match the values in globals.hpp, but scaled
2077   // with K. The values have been chosen so that alignment with page
2078   // size doesn't change the max value, which makes the conversions
2079   // back and forth between Xss value and ThreadStackSize value easier.
2080   // The values have also been chosen to fit inside a 32-bit signed type.
2081   const julong min_ThreadStackSize = 0;
2082   const julong max_ThreadStackSize = 1 * M;
2083 
2084   // Make sure the above values match the range set in globals.hpp
2085   const JVMTypedFlagLimit<intx>* limit = JVMFlagLimit::get_range_at(FLAG_MEMBER_ENUM(ThreadStackSize))->cast<intx>();
2086   assert(min_ThreadStackSize == static_cast<julong>(limit->min()), "must be");
2087   assert(max_ThreadStackSize == static_cast<julong>(limit->max()), "must be");
2088 
2089   const julong min_size = min_ThreadStackSize * K;
2090   const julong max_size = max_ThreadStackSize * K;
2091 
2092   assert(is_aligned(max_size, os::vm_page_size()), "Implementation assumption");
2093 
2094   julong size = 0;
2095   ArgsRange errcode = parse_memory_size(tail, &size, min_size, max_size);
2096   if (errcode != arg_in_range) {
2097     bool silent = (option == nullptr); // Allow testing to silence error messages
2098     if (!silent) {
2099       jio_fprintf(defaultStream::error_stream(),
2100                   "Invalid thread stack size: %s\n", option->optionString);
2101       describe_range_error(errcode);
2102     }
2103     return JNI_EINVAL;
2104   }
2105 
2106   // Internally track ThreadStackSize in units of 1024 bytes.
2107   const julong size_aligned = align_up(size, K);
2108   assert(size <= size_aligned,
2109          "Overflow: " JULONG_FORMAT " " JULONG_FORMAT,
2110          size, size_aligned);
2111 
2112   const julong size_in_K = size_aligned / K;
2113   assert(size_in_K < (julong)max_intx,
2114          "size_in_K doesn't fit in the type of ThreadStackSize: " JULONG_FORMAT,
2115          size_in_K);
2116 
2117   // Check that code expanding ThreadStackSize to a page aligned number of bytes won't overflow.
2118   const julong max_expanded = align_up(size_in_K * K, os::vm_page_size());
2119   assert(max_expanded < max_uintx && max_expanded >= size_in_K,
2120          "Expansion overflowed: " JULONG_FORMAT " " JULONG_FORMAT,
2121          max_expanded, size_in_K);
2122 
2123   *out_ThreadStackSize = (intx)size_in_K;
2124 
2125   return JNI_OK;
2126 }
2127 
2128 jint Arguments::parse_each_vm_init_arg(const JavaVMInitArgs* args, JVMFlagOrigin origin) {
2129   // For match_option to return remaining or value part of option string
2130   const char* tail;
2131 
2132   // iterate over arguments
2133   for (int index = 0; index < args->nOptions; index++) {
2134     bool is_absolute_path = false;  // for -agentpath vs -agentlib
2135 
2136     const JavaVMOption* option = args->options + index;
2137 
2138     if (!match_option(option, "-Djava.class.path", &tail) &&
2139         !match_option(option, "-Dsun.java.command", &tail) &&
2140         !match_option(option, "-Dsun.java.launcher", &tail)) {
2141 
2142         // add all jvm options to the jvm_args string. This string
2143         // is used later to set the java.vm.args PerfData string constant.
2144         // the -Djava.class.path and the -Dsun.java.command options are
2145         // omitted from jvm_args string as each have their own PerfData
2146         // string constant object.
2147         build_jvm_args(option->optionString);
2148     }
2149 
2150     // -verbose:[class/module/gc/jni]
2151     if (match_option(option, "-verbose", &tail)) {
2152       if (!strcmp(tail, ":class") || !strcmp(tail, "")) {
2153         LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(class, load));
2154         LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(class, unload));
2155       } else if (!strcmp(tail, ":module")) {
2156         LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(module, load));
2157         LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(module, unload));
2158       } else if (!strcmp(tail, ":gc")) {
2159         if (_legacyGCLogging.lastFlag == 0) {
2160           _legacyGCLogging.lastFlag = 1;
2161         }
2162       } else if (!strcmp(tail, ":jni")) {
2163         LogConfiguration::configure_stdout(LogLevel::Debug, true, LOG_TAGS(jni, resolve));
2164       }
2165     // -da / -ea / -disableassertions / -enableassertions
2166     // These accept an optional class/package name separated by a colon, e.g.,
2167     // -da:java.lang.Thread.
2168     } else if (match_option(option, user_assertion_options, &tail, true)) {
2169       bool enable = option->optionString[1] == 'e';     // char after '-' is 'e'
2170       if (*tail == '\0') {
2171         JavaAssertions::setUserClassDefault(enable);
2172       } else {
2173         assert(*tail == ':', "bogus match by match_option()");
2174         JavaAssertions::addOption(tail + 1, enable);
2175       }
2176     // -dsa / -esa / -disablesystemassertions / -enablesystemassertions
2177     } else if (match_option(option, system_assertion_options, &tail, false)) {
2178       bool enable = option->optionString[1] == 'e';     // char after '-' is 'e'
2179       JavaAssertions::setSystemClassDefault(enable);
2180     // -bootclasspath:
2181     } else if (match_option(option, "-Xbootclasspath:", &tail)) {
2182         jio_fprintf(defaultStream::output_stream(),
2183           "-Xbootclasspath is no longer a supported option.\n");
2184         return JNI_EINVAL;
2185     // -bootclasspath/a:
2186     } else if (match_option(option, "-Xbootclasspath/a:", &tail)) {
2187       Arguments::append_sysclasspath(tail);
2188     // -bootclasspath/p:
2189     } else if (match_option(option, "-Xbootclasspath/p:", &tail)) {
2190         jio_fprintf(defaultStream::output_stream(),
2191           "-Xbootclasspath/p is no longer a supported option.\n");
2192         return JNI_EINVAL;
2193     // -Xrun
2194     } else if (match_option(option, "-Xrun", &tail)) {
2195       if (tail != nullptr) {
2196         const char* pos = strchr(tail, ':');
2197         size_t len = (pos == nullptr) ? strlen(tail) : pos - tail;
2198         char* name = NEW_C_HEAP_ARRAY(char, len + 1, mtArguments);
2199         jio_snprintf(name, len + 1, "%s", tail);
2200 
2201         char *options = nullptr;
2202         if(pos != nullptr) {
2203           size_t len2 = strlen(pos+1) + 1; // options start after ':'.  Final zero must be copied.
2204           options = (char*)memcpy(NEW_C_HEAP_ARRAY(char, len2, mtArguments), pos+1, len2);
2205         }
2206 #if !INCLUDE_JVMTI
2207         if (strcmp(name, "jdwp") == 0) {
2208           jio_fprintf(defaultStream::error_stream(),
2209             "Debugging agents are not supported in this VM\n");
2210           return JNI_ERR;
2211         }
2212 #endif // !INCLUDE_JVMTI
2213         JvmtiAgentList::add_xrun(name, options, false);
2214         FREE_C_HEAP_ARRAY(char, name);
2215         FREE_C_HEAP_ARRAY(char, options);
2216       }
2217     } else if (match_option(option, "--add-reads=", &tail)) {
2218       if (!create_numbered_module_property("jdk.module.addreads", tail, addreads_count++)) {
2219         return JNI_ENOMEM;
2220       }
2221     } else if (match_option(option, "--add-exports=", &tail)) {
2222       if (!create_numbered_module_property("jdk.module.addexports", tail, addexports_count++)) {
2223         return JNI_ENOMEM;
2224       }
2225     } else if (match_option(option, "--add-opens=", &tail)) {
2226       if (!create_numbered_module_property("jdk.module.addopens", tail, addopens_count++)) {
2227         return JNI_ENOMEM;
2228       }
2229     } else if (match_option(option, "--add-modules=", &tail)) {
2230       if (!create_numbered_module_property("jdk.module.addmods", tail, _addmods_count++)) {
2231         return JNI_ENOMEM;
2232       }
2233 #if INCLUDE_JVMCI
2234       if (!_jvmci_module_added) {
2235         const char *jvmci_module = strstr(tail, "jdk.internal.vm.ci");
2236         if (jvmci_module != nullptr) {
2237           char before = *(jvmci_module - 1);
2238           char after  = *(jvmci_module + strlen("jdk.internal.vm.ci"));
2239           if ((before == '=' || before == ',') && (after == '\0' || after == ',')) {
2240             FLAG_SET_DEFAULT(EnableJVMCI, true);
2241             _jvmci_module_added = true;
2242           }
2243         }
2244       }
2245 #endif
2246     } else if (match_option(option, "--enable-native-access=", &tail)) {
2247       if (!create_numbered_module_property("jdk.module.enable.native.access", tail, enable_native_access_count++)) {
2248         return JNI_ENOMEM;
2249       }
2250     } else if (match_option(option, "--illegal-native-access=", &tail)) {
2251       if (!create_module_property("jdk.module.illegal.native.access", tail, InternalProperty)) {
2252         return JNI_ENOMEM;
2253       }
2254     } else if (match_option(option, "--limit-modules=", &tail)) {
2255       if (!create_module_property("jdk.module.limitmods", tail, InternalProperty)) {
2256         return JNI_ENOMEM;
2257       }
2258     } else if (match_option(option, "--module-path=", &tail)) {
2259       if (!create_module_property("jdk.module.path", tail, ExternalProperty)) {
2260         return JNI_ENOMEM;
2261       }
2262     } else if (match_option(option, "--upgrade-module-path=", &tail)) {
2263       if (!create_module_property("jdk.module.upgrade.path", tail, ExternalProperty)) {
2264         return JNI_ENOMEM;
2265       }
2266     } else if (match_option(option, "--patch-module=", &tail)) {
2267       // --patch-module=<module>=<file>(<pathsep><file>)*
2268       int res = process_patch_mod_option(tail);
2269       if (res != JNI_OK) {
2270         return res;
2271       }
2272     } else if (match_option(option, "--sun-misc-unsafe-memory-access=", &tail)) {
2273       if (strcmp(tail, "allow") == 0 || strcmp(tail, "warn") == 0 || strcmp(tail, "debug") == 0 || strcmp(tail, "deny") == 0) {
2274         PropertyList_unique_add(&_system_properties, "sun.misc.unsafe.memory.access", tail,
2275                                 AddProperty, WriteableProperty, InternalProperty);
2276       } else {
2277         jio_fprintf(defaultStream::error_stream(),
2278                     "Value specified to --sun-misc-unsafe-memory-access not recognized: '%s'\n", tail);
2279         return JNI_ERR;
2280       }
2281     } else if (match_option(option, "--illegal-access=", &tail)) {
2282       char version[256];
2283       JDK_Version::jdk(17).to_string(version, sizeof(version));
2284       warning("Ignoring option %s; support was removed in %s", option->optionString, version);
2285     // -agentlib and -agentpath
2286     } else if (match_option(option, "-agentlib:", &tail) ||
2287           (is_absolute_path = match_option(option, "-agentpath:", &tail))) {
2288       if(tail != nullptr) {
2289         const char* pos = strchr(tail, '=');
2290         char* name;
2291         if (pos == nullptr) {
2292           name = os::strdup_check_oom(tail, mtArguments);
2293         } else {
2294           size_t len = pos - tail;
2295           name = NEW_C_HEAP_ARRAY(char, len + 1, mtArguments);
2296           memcpy(name, tail, len);
2297           name[len] = '\0';
2298         }
2299 
2300         char *options = nullptr;
2301         if(pos != nullptr) {
2302           options = os::strdup_check_oom(pos + 1, mtArguments);
2303         }
2304 #if !INCLUDE_JVMTI
2305         if (valid_jdwp_agent(name, is_absolute_path)) {
2306           jio_fprintf(defaultStream::error_stream(),
2307             "Debugging agents are not supported in this VM\n");
2308           return JNI_ERR;
2309         }
2310 #elif INCLUDE_CDS
2311         if (valid_jdwp_agent(name, is_absolute_path)) {
2312           _has_jdwp_agent = true;
2313         }
2314 #endif // !INCLUDE_JVMTI
2315         JvmtiAgentList::add(name, options, is_absolute_path);
2316         os::free(name);
2317         os::free(options);
2318       }
2319     // -javaagent
2320     } else if (match_option(option, "-javaagent:", &tail)) {
2321 #if !INCLUDE_JVMTI
2322       jio_fprintf(defaultStream::error_stream(),
2323         "Instrumentation agents are not supported in this VM\n");
2324       return JNI_ERR;
2325 #else
2326       if (tail != nullptr) {
2327         size_t length = strlen(tail) + 1;
2328         char *options = NEW_C_HEAP_ARRAY(char, length, mtArguments);
2329         jio_snprintf(options, length, "%s", tail);
2330         JvmtiAgentList::add("instrument", options, false);
2331         FREE_C_HEAP_ARRAY(char, options);
2332 
2333         // java agents need module java.instrument
2334         if (!create_numbered_module_property("jdk.module.addmods", "java.instrument", _addmods_count++)) {
2335           return JNI_ENOMEM;
2336         }
2337       }
2338 #endif // !INCLUDE_JVMTI
2339     // --enable_preview
2340     } else if (match_option(option, "--enable-preview")) {
2341       set_enable_preview();
2342     // -Xnoclassgc
2343     } else if (match_option(option, "-Xnoclassgc")) {
2344       if (FLAG_SET_CMDLINE(ClassUnloading, false) != JVMFlag::SUCCESS) {
2345         return JNI_EINVAL;
2346       }
2347     // -Xbatch
2348     } else if (match_option(option, "-Xbatch")) {
2349       if (FLAG_SET_CMDLINE(BackgroundCompilation, false) != JVMFlag::SUCCESS) {
2350         return JNI_EINVAL;
2351       }
2352     // -Xmn for compatibility with other JVM vendors
2353     } else if (match_option(option, "-Xmn", &tail)) {
2354       julong long_initial_young_size = 0;
2355       ArgsRange errcode = parse_memory_size(tail, &long_initial_young_size, 1);
2356       if (errcode != arg_in_range) {
2357         jio_fprintf(defaultStream::error_stream(),
2358                     "Invalid initial young generation size: %s\n", option->optionString);
2359         describe_range_error(errcode);
2360         return JNI_EINVAL;
2361       }
2362       if (FLAG_SET_CMDLINE(MaxNewSize, (size_t)long_initial_young_size) != JVMFlag::SUCCESS) {
2363         return JNI_EINVAL;
2364       }
2365       if (FLAG_SET_CMDLINE(NewSize, (size_t)long_initial_young_size) != JVMFlag::SUCCESS) {
2366         return JNI_EINVAL;
2367       }
2368     // -Xms
2369     } else if (match_option(option, "-Xms", &tail)) {
2370       julong size = 0;
2371       // an initial heap size of 0 means automatically determine
2372       ArgsRange errcode = parse_memory_size(tail, &size, 0);
2373       if (errcode != arg_in_range) {
2374         jio_fprintf(defaultStream::error_stream(),
2375                     "Invalid initial heap size: %s\n", option->optionString);
2376         describe_range_error(errcode);
2377         return JNI_EINVAL;
2378       }
2379       if (FLAG_SET_CMDLINE(MinHeapSize, (size_t)size) != JVMFlag::SUCCESS) {
2380         return JNI_EINVAL;
2381       }
2382       if (FLAG_SET_CMDLINE(InitialHeapSize, (size_t)size) != JVMFlag::SUCCESS) {
2383         return JNI_EINVAL;
2384       }
2385     // -Xmx
2386     } else if (match_option(option, "-Xmx", &tail) || match_option(option, "-XX:MaxHeapSize=", &tail)) {
2387       julong long_max_heap_size = 0;
2388       ArgsRange errcode = parse_memory_size(tail, &long_max_heap_size, 1);
2389       if (errcode != arg_in_range) {
2390         jio_fprintf(defaultStream::error_stream(),
2391                     "Invalid maximum heap size: %s\n", option->optionString);
2392         describe_range_error(errcode);
2393         return JNI_EINVAL;
2394       }
2395       if (FLAG_SET_CMDLINE(MaxHeapSize, (size_t)long_max_heap_size) != JVMFlag::SUCCESS) {
2396         return JNI_EINVAL;
2397       }
2398     // Xmaxf
2399     } else if (match_option(option, "-Xmaxf", &tail)) {
2400       char* err;
2401       double dmaxf = strtod(tail, &err);
2402       if (*err != '\0' || *tail == '\0') {
2403         jio_fprintf(defaultStream::error_stream(),
2404                     "Bad max heap free ratio: %s\n",
2405                     option->optionString);
2406         return JNI_EINVAL;
2407       }
2408       if (dmaxf < 0.0 || dmaxf > 1.0) {
2409         jio_fprintf(defaultStream::error_stream(),
2410                     "-Xmaxf value (%s) is outside the allowed range [ 0.0 ... 1.0 ]\n",
2411                     option->optionString);
2412         return JNI_EINVAL;
2413       }
2414       const uintx umaxf = (uintx)(dmaxf * 100);
2415       if (MinHeapFreeRatio > umaxf) {
2416         jio_fprintf(defaultStream::error_stream(),
2417                     "-Xmaxf value (%s) must be greater than or equal to the implicit -Xminf value (%.2f)\n",
2418                     tail, MinHeapFreeRatio / 100.0f);
2419         return JNI_EINVAL;
2420       }
2421       if (FLAG_SET_CMDLINE(MaxHeapFreeRatio, umaxf) != JVMFlag::SUCCESS) {
2422         return JNI_EINVAL;
2423       }
2424     // Xminf
2425     } else if (match_option(option, "-Xminf", &tail)) {
2426       char* err;
2427       double dminf = strtod(tail, &err);
2428       if (*err != '\0' || *tail == '\0') {
2429         jio_fprintf(defaultStream::error_stream(),
2430                     "Bad min heap free ratio: %s\n",
2431                     option->optionString);
2432         return JNI_EINVAL;
2433       }
2434       if (dminf < 0.0 || dminf > 1.0) {
2435         jio_fprintf(defaultStream::error_stream(),
2436                     "-Xminf value (%s) is outside the allowed range [ 0.0 ... 1.0 ]\n",
2437                     tail);
2438         return JNI_EINVAL;
2439       }
2440       const uintx uminf = (uintx)(dminf * 100);
2441       if (MaxHeapFreeRatio < uminf) {
2442         jio_fprintf(defaultStream::error_stream(),
2443                     "-Xminf value (%s) must be less than or equal to the implicit -Xmaxf value (%.2f)\n",
2444                     tail, MaxHeapFreeRatio / 100.0f);
2445         return JNI_EINVAL;
2446       }
2447       if (FLAG_SET_CMDLINE(MinHeapFreeRatio, uminf) != JVMFlag::SUCCESS) {
2448         return JNI_EINVAL;
2449       }
2450     // -Xss
2451     } else if (match_option(option, "-Xss", &tail)) {
2452       intx value = 0;
2453       jint err = parse_xss(option, tail, &value);
2454       if (err != JNI_OK) {
2455         return err;
2456       }
2457       if (FLAG_SET_CMDLINE(ThreadStackSize, value) != JVMFlag::SUCCESS) {
2458         return JNI_EINVAL;
2459       }
2460     } else if (match_option(option, "-Xmaxjitcodesize", &tail) ||
2461                match_option(option, "-XX:ReservedCodeCacheSize=", &tail)) {
2462       julong long_ReservedCodeCacheSize = 0;
2463 
2464       ArgsRange errcode = parse_memory_size(tail, &long_ReservedCodeCacheSize, 1);
2465       if (errcode != arg_in_range) {
2466         jio_fprintf(defaultStream::error_stream(),
2467                     "Invalid maximum code cache size: %s.\n", option->optionString);
2468         return JNI_EINVAL;
2469       }
2470       if (FLAG_SET_CMDLINE(ReservedCodeCacheSize, (size_t)long_ReservedCodeCacheSize) != JVMFlag::SUCCESS) {
2471         return JNI_EINVAL;
2472       }
2473     // -green
2474     } else if (match_option(option, "-green")) {
2475       jio_fprintf(defaultStream::error_stream(),
2476                   "Green threads support not available\n");
2477           return JNI_EINVAL;
2478     // -native
2479     } else if (match_option(option, "-native")) {
2480           // HotSpot always uses native threads, ignore silently for compatibility
2481     // -Xrs
2482     } else if (match_option(option, "-Xrs")) {
2483           // Classic/EVM option, new functionality
2484       if (FLAG_SET_CMDLINE(ReduceSignalUsage, true) != JVMFlag::SUCCESS) {
2485         return JNI_EINVAL;
2486       }
2487       // -Xprof
2488     } else if (match_option(option, "-Xprof")) {
2489       char version[256];
2490       // Obsolete in JDK 10
2491       JDK_Version::jdk(10).to_string(version, sizeof(version));
2492       warning("Ignoring option %s; support was removed in %s", option->optionString, version);
2493     // -Xinternalversion
2494     } else if (match_option(option, "-Xinternalversion")) {
2495       jio_fprintf(defaultStream::output_stream(), "%s\n",
2496                   VM_Version::internal_vm_info_string());
2497       vm_exit(0);
2498 #ifndef PRODUCT
2499     // -Xprintflags
2500     } else if (match_option(option, "-Xprintflags")) {
2501       JVMFlag::printFlags(tty, false);
2502       vm_exit(0);
2503 #endif
2504     // -D
2505     } else if (match_option(option, "-D", &tail)) {
2506       const char* value;
2507       if (match_option(option, "-Djava.endorsed.dirs=", &value) &&
2508             *value!= '\0' && strcmp(value, "\"\"") != 0) {
2509         // abort if -Djava.endorsed.dirs is set
2510         jio_fprintf(defaultStream::output_stream(),
2511           "-Djava.endorsed.dirs=%s is not supported. Endorsed standards and standalone APIs\n"
2512           "in modular form will be supported via the concept of upgradeable modules.\n", value);
2513         return JNI_EINVAL;
2514       }
2515       if (match_option(option, "-Djava.ext.dirs=", &value) &&
2516             *value != '\0' && strcmp(value, "\"\"") != 0) {
2517         // abort if -Djava.ext.dirs is set
2518         jio_fprintf(defaultStream::output_stream(),
2519           "-Djava.ext.dirs=%s is not supported.  Use -classpath instead.\n", value);
2520         return JNI_EINVAL;
2521       }
2522       // Check for module related properties.  They must be set using the modules
2523       // options. For example: use "--add-modules=java.sql", not
2524       // "-Djdk.module.addmods=java.sql"
2525       if (is_internal_module_property(option->optionString + 2)) {
2526         needs_module_property_warning = true;
2527         continue;
2528       }
2529       if (!add_property(tail)) {
2530         return JNI_ENOMEM;
2531       }
2532       // Out of the box management support
2533       if (match_option(option, "-Dcom.sun.management", &tail)) {
2534 #if INCLUDE_MANAGEMENT
2535         if (FLAG_SET_CMDLINE(ManagementServer, true) != JVMFlag::SUCCESS) {
2536           return JNI_EINVAL;
2537         }
2538         // management agent in module jdk.management.agent
2539         if (!create_numbered_module_property("jdk.module.addmods", "jdk.management.agent", _addmods_count++)) {
2540           return JNI_ENOMEM;
2541         }
2542 #else
2543         jio_fprintf(defaultStream::output_stream(),
2544           "-Dcom.sun.management is not supported in this VM.\n");
2545         return JNI_ERR;
2546 #endif
2547       }
2548     // -Xint
2549     } else if (match_option(option, "-Xint")) {
2550           set_mode_flags(_int);
2551           mode_flag_cmd_line = true;
2552     // -Xmixed
2553     } else if (match_option(option, "-Xmixed")) {
2554           set_mode_flags(_mixed);
2555           mode_flag_cmd_line = true;
2556     // -Xcomp
2557     } else if (match_option(option, "-Xcomp")) {
2558       // for testing the compiler; turn off all flags that inhibit compilation
2559           set_mode_flags(_comp);
2560           mode_flag_cmd_line = true;
2561     // -Xshare:dump
2562     } else if (match_option(option, "-Xshare:dump")) {
2563       CDSConfig::enable_dumping_static_archive();
2564       CDSConfig::set_old_cds_flags_used();
2565     // -Xshare:on
2566     } else if (match_option(option, "-Xshare:on")) {
2567       UseSharedSpaces = true;
2568       RequireSharedSpaces = true;
2569       CDSConfig::set_old_cds_flags_used();
2570     // -Xshare:auto || -XX:ArchiveClassesAtExit=<archive file>
2571     } else if (match_option(option, "-Xshare:auto")) {
2572       UseSharedSpaces = true;
2573       RequireSharedSpaces = false;
2574       xshare_auto_cmd_line = true;
2575       CDSConfig::set_old_cds_flags_used();
2576     // -Xshare:off
2577     } else if (match_option(option, "-Xshare:off")) {
2578       UseSharedSpaces = false;
2579       RequireSharedSpaces = false;
2580       CDSConfig::set_old_cds_flags_used();
2581     // -Xverify
2582     } else if (match_option(option, "-Xverify", &tail)) {
2583       if (strcmp(tail, ":all") == 0 || strcmp(tail, "") == 0) {
2584         if (FLAG_SET_CMDLINE(BytecodeVerificationLocal, true) != JVMFlag::SUCCESS) {
2585           return JNI_EINVAL;
2586         }
2587         if (FLAG_SET_CMDLINE(BytecodeVerificationRemote, true) != JVMFlag::SUCCESS) {
2588           return JNI_EINVAL;
2589         }
2590       } else if (strcmp(tail, ":remote") == 0) {
2591         if (FLAG_SET_CMDLINE(BytecodeVerificationLocal, false) != JVMFlag::SUCCESS) {
2592           return JNI_EINVAL;
2593         }
2594         if (FLAG_SET_CMDLINE(BytecodeVerificationRemote, true) != JVMFlag::SUCCESS) {
2595           return JNI_EINVAL;
2596         }
2597       } else if (strcmp(tail, ":none") == 0) {
2598         if (FLAG_SET_CMDLINE(BytecodeVerificationLocal, false) != JVMFlag::SUCCESS) {
2599           return JNI_EINVAL;
2600         }
2601         if (FLAG_SET_CMDLINE(BytecodeVerificationRemote, false) != JVMFlag::SUCCESS) {
2602           return JNI_EINVAL;
2603         }
2604         warning("Options -Xverify:none and -noverify were deprecated in JDK 13 and will likely be removed in a future release.");
2605       } else if (is_bad_option(option, args->ignoreUnrecognized, "verification")) {
2606         return JNI_EINVAL;
2607       }
2608     // -Xdebug
2609     } else if (match_option(option, "-Xdebug")) {
2610       warning("Option -Xdebug was deprecated in JDK 22 and will likely be removed in a future release.");
2611     } else if (match_option(option, "-Xloggc:", &tail)) {
2612       // Deprecated flag to redirect GC output to a file. -Xloggc:<filename>
2613       log_warning(gc)("-Xloggc is deprecated. Will use -Xlog:gc:%s instead.", tail);
2614       _legacyGCLogging.lastFlag = 2;
2615       _legacyGCLogging.file = os::strdup_check_oom(tail);
2616     } else if (match_option(option, "-Xlog", &tail)) {
2617       bool ret = false;
2618       if (strcmp(tail, ":help") == 0) {
2619         fileStream stream(defaultStream::output_stream());
2620         LogConfiguration::print_command_line_help(&stream);
2621         vm_exit(0);
2622       } else if (strcmp(tail, ":disable") == 0) {
2623         LogConfiguration::disable_logging();
2624         ret = true;
2625       } else if (strncmp(tail, ":async", strlen(":async")) == 0) {
2626         const char* async_tail = tail + strlen(":async");
2627         ret = LogConfiguration::parse_async_argument(async_tail);
2628       } else if (*tail == '\0') {
2629         ret = LogConfiguration::parse_command_line_arguments();
2630         assert(ret, "-Xlog without arguments should never fail to parse");
2631       } else if (*tail == ':') {
2632         ret = LogConfiguration::parse_command_line_arguments(tail + 1);
2633       }
2634       if (ret == false) {
2635         jio_fprintf(defaultStream::error_stream(),
2636                     "Invalid -Xlog option '-Xlog%s', see error log for details.\n",
2637                     tail);
2638         return JNI_EINVAL;
2639       }
2640     // JNI hooks
2641     } else if (match_option(option, "-Xcheck", &tail)) {
2642       if (!strcmp(tail, ":jni")) {
2643 #if !INCLUDE_JNI_CHECK
2644         warning("JNI CHECKING is not supported in this VM");
2645 #else
2646         CheckJNICalls = true;
2647 #endif // INCLUDE_JNI_CHECK
2648       } else if (is_bad_option(option, args->ignoreUnrecognized,
2649                                      "check")) {
2650         return JNI_EINVAL;
2651       }
2652     } else if (match_option(option, "vfprintf")) {
2653       _vfprintf_hook = CAST_TO_FN_PTR(vfprintf_hook_t, option->extraInfo);
2654     } else if (match_option(option, "exit")) {
2655       _exit_hook = CAST_TO_FN_PTR(exit_hook_t, option->extraInfo);
2656     } else if (match_option(option, "abort")) {
2657       _abort_hook = CAST_TO_FN_PTR(abort_hook_t, option->extraInfo);
2658     // Need to keep consistency of MaxTenuringThreshold and AlwaysTenure/NeverTenure;
2659     // and the last option wins.
2660     } else if (match_option(option, "-XX:+NeverTenure")) {
2661       if (FLAG_SET_CMDLINE(NeverTenure, true) != JVMFlag::SUCCESS) {
2662         return JNI_EINVAL;
2663       }
2664       if (FLAG_SET_CMDLINE(AlwaysTenure, false) != JVMFlag::SUCCESS) {
2665         return JNI_EINVAL;
2666       }
2667       if (FLAG_SET_CMDLINE(MaxTenuringThreshold, markWord::max_age + 1) != JVMFlag::SUCCESS) {
2668         return JNI_EINVAL;
2669       }
2670     } else if (match_option(option, "-XX:+AlwaysTenure")) {
2671       if (FLAG_SET_CMDLINE(NeverTenure, false) != JVMFlag::SUCCESS) {
2672         return JNI_EINVAL;
2673       }
2674       if (FLAG_SET_CMDLINE(AlwaysTenure, true) != JVMFlag::SUCCESS) {
2675         return JNI_EINVAL;
2676       }
2677       if (FLAG_SET_CMDLINE(MaxTenuringThreshold, 0) != JVMFlag::SUCCESS) {
2678         return JNI_EINVAL;
2679       }
2680     } else if (match_option(option, "-XX:MaxTenuringThreshold=", &tail)) {
2681       uint max_tenuring_thresh = 0;
2682       if (!parse_uint(tail, &max_tenuring_thresh, 0)) {
2683         jio_fprintf(defaultStream::error_stream(),
2684                     "Improperly specified VM option \'MaxTenuringThreshold=%s\'\n", tail);
2685         return JNI_EINVAL;
2686       }
2687 
2688       if (FLAG_SET_CMDLINE(MaxTenuringThreshold, max_tenuring_thresh) != JVMFlag::SUCCESS) {
2689         return JNI_EINVAL;
2690       }
2691 
2692       if (MaxTenuringThreshold == 0) {
2693         if (FLAG_SET_CMDLINE(NeverTenure, false) != JVMFlag::SUCCESS) {
2694           return JNI_EINVAL;
2695         }
2696         if (FLAG_SET_CMDLINE(AlwaysTenure, true) != JVMFlag::SUCCESS) {
2697           return JNI_EINVAL;
2698         }
2699       } else {
2700         if (FLAG_SET_CMDLINE(NeverTenure, false) != JVMFlag::SUCCESS) {
2701           return JNI_EINVAL;
2702         }
2703         if (FLAG_SET_CMDLINE(AlwaysTenure, false) != JVMFlag::SUCCESS) {
2704           return JNI_EINVAL;
2705         }
2706       }
2707     } else if (match_option(option, "-XX:+DisplayVMOutputToStderr")) {
2708       if (FLAG_SET_CMDLINE(DisplayVMOutputToStdout, false) != JVMFlag::SUCCESS) {
2709         return JNI_EINVAL;
2710       }
2711       if (FLAG_SET_CMDLINE(DisplayVMOutputToStderr, true) != JVMFlag::SUCCESS) {
2712         return JNI_EINVAL;
2713       }
2714     } else if (match_option(option, "-XX:+DisplayVMOutputToStdout")) {
2715       if (FLAG_SET_CMDLINE(DisplayVMOutputToStderr, false) != JVMFlag::SUCCESS) {
2716         return JNI_EINVAL;
2717       }
2718       if (FLAG_SET_CMDLINE(DisplayVMOutputToStdout, true) != JVMFlag::SUCCESS) {
2719         return JNI_EINVAL;
2720       }
2721     } else if (match_option(option, "-XX:+ErrorFileToStderr")) {
2722       if (FLAG_SET_CMDLINE(ErrorFileToStdout, false) != JVMFlag::SUCCESS) {
2723         return JNI_EINVAL;
2724       }
2725       if (FLAG_SET_CMDLINE(ErrorFileToStderr, true) != JVMFlag::SUCCESS) {
2726         return JNI_EINVAL;
2727       }
2728     } else if (match_option(option, "-XX:+ErrorFileToStdout")) {
2729       if (FLAG_SET_CMDLINE(ErrorFileToStderr, false) != JVMFlag::SUCCESS) {
2730         return JNI_EINVAL;
2731       }
2732       if (FLAG_SET_CMDLINE(ErrorFileToStdout, true) != JVMFlag::SUCCESS) {
2733         return JNI_EINVAL;
2734       }
2735     } else if (match_option(option, "--finalization=", &tail)) {
2736       if (strcmp(tail, "enabled") == 0) {
2737         InstanceKlass::set_finalization_enabled(true);
2738       } else if (strcmp(tail, "disabled") == 0) {
2739         InstanceKlass::set_finalization_enabled(false);
2740       } else {
2741         jio_fprintf(defaultStream::error_stream(),
2742                     "Invalid finalization value '%s', must be 'disabled' or 'enabled'.\n",
2743                     tail);
2744         return JNI_EINVAL;
2745       }
2746 #if !defined(DTRACE_ENABLED)
2747     } else if (match_option(option, "-XX:+DTraceMethodProbes")) {
2748       jio_fprintf(defaultStream::error_stream(),
2749                   "DTraceMethodProbes flag is not applicable for this configuration\n");
2750       return JNI_EINVAL;
2751     } else if (match_option(option, "-XX:+DTraceAllocProbes")) {
2752       jio_fprintf(defaultStream::error_stream(),
2753                   "DTraceAllocProbes flag is not applicable for this configuration\n");
2754       return JNI_EINVAL;
2755     } else if (match_option(option, "-XX:+DTraceMonitorProbes")) {
2756       jio_fprintf(defaultStream::error_stream(),
2757                   "DTraceMonitorProbes flag is not applicable for this configuration\n");
2758       return JNI_EINVAL;
2759 #endif // !defined(DTRACE_ENABLED)
2760 #ifdef ASSERT
2761     } else if (match_option(option, "-XX:+FullGCALot")) {
2762       if (FLAG_SET_CMDLINE(FullGCALot, true) != JVMFlag::SUCCESS) {
2763         return JNI_EINVAL;
2764       }
2765 #endif
2766 #if !INCLUDE_MANAGEMENT
2767     } else if (match_option(option, "-XX:+ManagementServer")) {
2768         jio_fprintf(defaultStream::error_stream(),
2769           "ManagementServer is not supported in this VM.\n");
2770         return JNI_ERR;
2771 #endif // INCLUDE_MANAGEMENT
2772 #if INCLUDE_JVMCI
2773     } else if (match_option(option, "-XX:-EnableJVMCIProduct") || match_option(option, "-XX:-UseGraalJIT")) {
2774       if (EnableJVMCIProduct) {
2775         jio_fprintf(defaultStream::error_stream(),
2776                   "-XX:-EnableJVMCIProduct or -XX:-UseGraalJIT cannot come after -XX:+EnableJVMCIProduct or -XX:+UseGraalJIT\n");
2777         return JNI_EINVAL;
2778       }
2779     } else if (match_option(option, "-XX:+EnableJVMCIProduct") || match_option(option, "-XX:+UseGraalJIT")) {
2780       bool use_graal_jit = match_option(option, "-XX:+UseGraalJIT");
2781       if (use_graal_jit) {
2782         const char* jvmci_compiler = get_property("jvmci.Compiler");
2783         if (jvmci_compiler != nullptr) {
2784           if (strncmp(jvmci_compiler, "graal", strlen("graal")) != 0) {
2785             jio_fprintf(defaultStream::error_stream(),
2786               "Value of jvmci.Compiler incompatible with +UseGraalJIT: %s\n", jvmci_compiler);
2787             return JNI_ERR;
2788           }
2789         } else if (!add_property("jvmci.Compiler=graal")) {
2790             return JNI_ENOMEM;
2791         }
2792       }
2793 
2794       // Just continue, since "-XX:+EnableJVMCIProduct" or "-XX:+UseGraalJIT" has been specified before
2795       if (EnableJVMCIProduct) {
2796         continue;
2797       }
2798       JVMFlag *jvmciFlag = JVMFlag::find_flag("EnableJVMCIProduct");
2799       // Allow this flag if it has been unlocked.
2800       if (jvmciFlag != nullptr && jvmciFlag->is_unlocked()) {
2801         if (!JVMCIGlobals::enable_jvmci_product_mode(origin, use_graal_jit)) {
2802           jio_fprintf(defaultStream::error_stream(),
2803             "Unable to enable JVMCI in product mode\n");
2804           return JNI_ERR;
2805         }
2806       }
2807       // The flag was locked so process normally to report that error
2808       else if (!process_argument(use_graal_jit ? "UseGraalJIT" : "EnableJVMCIProduct", args->ignoreUnrecognized, origin)) {
2809         return JNI_EINVAL;
2810       }
2811 #endif // INCLUDE_JVMCI
2812 #if INCLUDE_JFR
2813     } else if (match_jfr_option(&option)) {
2814       return JNI_EINVAL;
2815 #endif
2816     } else if (match_option(option, "-XX:", &tail)) { // -XX:xxxx
2817       // Skip -XX:Flags= and -XX:VMOptionsFile= since those cases have
2818       // already been handled
2819       if ((strncmp(tail, "Flags=", strlen("Flags=")) != 0) &&
2820           (strncmp(tail, "VMOptionsFile=", strlen("VMOptionsFile=")) != 0)) {
2821         if (!process_argument(tail, args->ignoreUnrecognized, origin)) {
2822           return JNI_EINVAL;
2823         }
2824       }
2825     // Unknown option
2826     } else if (is_bad_option(option, args->ignoreUnrecognized)) {
2827       return JNI_ERR;
2828     }
2829   }
2830 
2831   // PrintSharedArchiveAndExit will turn on
2832   //   -Xshare:on
2833   //   -Xlog:class+path=info
2834   if (PrintSharedArchiveAndExit) {
2835     UseSharedSpaces = true;
2836     RequireSharedSpaces = true;
2837     LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(class, path));
2838   }
2839 
2840   fix_appclasspath();
2841 
2842   return JNI_OK;
2843 }
2844 
2845 void Arguments::add_patch_mod_prefix(const char* module_name, const char* path) {
2846   // For java.base check for duplicate --patch-module options being specified on the command line.
2847   // This check is only required for java.base, all other duplicate module specifications
2848   // will be checked during module system initialization.  The module system initialization
2849   // will throw an ExceptionInInitializerError if this situation occurs.
2850   if (strcmp(module_name, JAVA_BASE_NAME) == 0) {
2851     if (patch_mod_javabase) {
2852       vm_exit_during_initialization("Cannot specify " JAVA_BASE_NAME " more than once to --patch-module");
2853     } else {
2854       patch_mod_javabase = true;
2855     }
2856   }
2857 
2858   // Create GrowableArray lazily, only if --patch-module has been specified
2859   if (_patch_mod_prefix == nullptr) {
2860     _patch_mod_prefix = new (mtArguments) GrowableArray<ModulePatchPath*>(10, mtArguments);
2861   }
2862 
2863   _patch_mod_prefix->push(new ModulePatchPath(module_name, path));
2864 }
2865 
2866 // Remove all empty paths from the app classpath (if IgnoreEmptyClassPaths is enabled)
2867 //
2868 // This is necessary because some apps like to specify classpath like -cp foo.jar:${XYZ}:bar.jar
2869 // in their start-up scripts. If XYZ is empty, the classpath will look like "-cp foo.jar::bar.jar".
2870 // Java treats such empty paths as if the user specified "-cp foo.jar:.:bar.jar". I.e., an empty
2871 // path is treated as the current directory.
2872 //
2873 // This causes problems with CDS, which requires that all directories specified in the classpath
2874 // must be empty. In most cases, applications do NOT want to load classes from the current
2875 // directory anyway. Adding -XX:+IgnoreEmptyClassPaths will make these applications' start-up
2876 // scripts compatible with CDS.
2877 void Arguments::fix_appclasspath() {
2878   if (IgnoreEmptyClassPaths) {
2879     const char separator = *os::path_separator();
2880     const char* src = _java_class_path->value();
2881 
2882     // skip over all the leading empty paths
2883     while (*src == separator) {
2884       src ++;
2885     }
2886 
2887     char* copy = os::strdup_check_oom(src, mtArguments);
2888 
2889     // trim all trailing empty paths
2890     for (char* tail = copy + strlen(copy) - 1; tail >= copy && *tail == separator; tail--) {
2891       *tail = '\0';
2892     }
2893 
2894     char from[3] = {separator, separator, '\0'};
2895     char to  [2] = {separator, '\0'};
2896     while (StringUtils::replace_no_expand(copy, from, to) > 0) {
2897       // Keep replacing "::" -> ":" until we have no more "::" (non-windows)
2898       // Keep replacing ";;" -> ";" until we have no more ";;" (windows)
2899     }
2900 
2901     _java_class_path->set_writeable_value(copy);
2902     FreeHeap(copy); // a copy was made by set_value, so don't need this anymore
2903   }
2904 }
2905 
2906 jint Arguments::finalize_vm_init_args() {
2907   // check if the default lib/endorsed directory exists; if so, error
2908   char path[JVM_MAXPATHLEN];
2909   const char* fileSep = os::file_separator();
2910   jio_snprintf(path, JVM_MAXPATHLEN, "%s%slib%sendorsed", Arguments::get_java_home(), fileSep, fileSep);
2911 
2912   DIR* dir = os::opendir(path);
2913   if (dir != nullptr) {
2914     jio_fprintf(defaultStream::output_stream(),
2915       "<JAVA_HOME>/lib/endorsed is not supported. Endorsed standards and standalone APIs\n"
2916       "in modular form will be supported via the concept of upgradeable modules.\n");
2917     os::closedir(dir);
2918     return JNI_ERR;
2919   }
2920 
2921   jio_snprintf(path, JVM_MAXPATHLEN, "%s%slib%sext", Arguments::get_java_home(), fileSep, fileSep);
2922   dir = os::opendir(path);
2923   if (dir != nullptr) {
2924     jio_fprintf(defaultStream::output_stream(),
2925       "<JAVA_HOME>/lib/ext exists, extensions mechanism no longer supported; "
2926       "Use -classpath instead.\n.");
2927     os::closedir(dir);
2928     return JNI_ERR;
2929   }
2930 
2931   // This must be done after all arguments have been processed
2932   // and the container support has been initialized since AggressiveHeap
2933   // relies on the amount of total memory available.
2934   if (AggressiveHeap) {
2935     jint result = set_aggressive_heap_flags();
2936     if (result != JNI_OK) {
2937       return result;
2938     }
2939   }
2940 
2941   // CompileThresholdScaling == 0.0 is same as -Xint: Disable compilation (enable interpreter-only mode),
2942   // but like -Xint, leave compilation thresholds unaffected.
2943   // With tiered compilation disabled, setting CompileThreshold to 0 disables compilation as well.
2944   if ((CompileThresholdScaling == 0.0) || (!TieredCompilation && CompileThreshold == 0)) {
2945     set_mode_flags(_int);
2946   }
2947 
2948 #ifdef ZERO
2949   // Zero always runs in interpreted mode
2950   set_mode_flags(_int);
2951 #endif
2952 
2953   // eventually fix up InitialTenuringThreshold if only MaxTenuringThreshold is set
2954   if (FLAG_IS_DEFAULT(InitialTenuringThreshold) && (InitialTenuringThreshold > MaxTenuringThreshold)) {
2955     FLAG_SET_ERGO(InitialTenuringThreshold, MaxTenuringThreshold);
2956   }
2957 
2958 #if !COMPILER2_OR_JVMCI
2959   // Don't degrade server performance for footprint
2960   if (FLAG_IS_DEFAULT(UseLargePages) &&
2961       MaxHeapSize < LargePageHeapSizeThreshold) {
2962     // No need for large granularity pages w/small heaps.
2963     // Note that large pages are enabled/disabled for both the
2964     // Java heap and the code cache.
2965     FLAG_SET_DEFAULT(UseLargePages, false);
2966   }
2967 
2968   UNSUPPORTED_OPTION(ProfileInterpreter);
2969 #endif
2970 
2971   // Parse the CompilationMode flag
2972   if (!CompilationModeFlag::initialize()) {
2973     return JNI_ERR;
2974   }
2975 
2976   if (!check_vm_args_consistency()) {
2977     return JNI_ERR;
2978   }
2979 
2980 
2981 #ifndef CAN_SHOW_REGISTERS_ON_ASSERT
2982   UNSUPPORTED_OPTION(ShowRegistersOnAssert);
2983 #endif // CAN_SHOW_REGISTERS_ON_ASSERT
2984 
2985   return JNI_OK;
2986 }
2987 
2988 // Helper class for controlling the lifetime of JavaVMInitArgs
2989 // objects.  The contents of the JavaVMInitArgs are guaranteed to be
2990 // deleted on the destruction of the ScopedVMInitArgs object.
2991 class ScopedVMInitArgs : public StackObj {
2992  private:
2993   JavaVMInitArgs _args;
2994   char*          _container_name;
2995   bool           _is_set;
2996   char*          _vm_options_file_arg;
2997 
2998  public:
2999   ScopedVMInitArgs(const char *container_name) {
3000     _args.version = JNI_VERSION_1_2;
3001     _args.nOptions = 0;
3002     _args.options = nullptr;
3003     _args.ignoreUnrecognized = false;
3004     _container_name = (char *)container_name;
3005     _is_set = false;
3006     _vm_options_file_arg = nullptr;
3007   }
3008 
3009   // Populates the JavaVMInitArgs object represented by this
3010   // ScopedVMInitArgs object with the arguments in options.  The
3011   // allocated memory is deleted by the destructor.  If this method
3012   // returns anything other than JNI_OK, then this object is in a
3013   // partially constructed state, and should be abandoned.
3014   jint set_args(const GrowableArrayView<JavaVMOption>* options) {
3015     _is_set = true;
3016     JavaVMOption* options_arr = NEW_C_HEAP_ARRAY_RETURN_NULL(
3017         JavaVMOption, options->length(), mtArguments);
3018     if (options_arr == nullptr) {
3019       return JNI_ENOMEM;
3020     }
3021     _args.options = options_arr;
3022 
3023     for (int i = 0; i < options->length(); i++) {
3024       options_arr[i] = options->at(i);
3025       options_arr[i].optionString = os::strdup(options_arr[i].optionString);
3026       if (options_arr[i].optionString == nullptr) {
3027         // Rely on the destructor to do cleanup.
3028         _args.nOptions = i;
3029         return JNI_ENOMEM;
3030       }
3031     }
3032 
3033     _args.nOptions = options->length();
3034     _args.ignoreUnrecognized = IgnoreUnrecognizedVMOptions;
3035     return JNI_OK;
3036   }
3037 
3038   JavaVMInitArgs* get()             { return &_args; }
3039   char* container_name()            { return _container_name; }
3040   bool  is_set()                    { return _is_set; }
3041   bool  found_vm_options_file_arg() { return _vm_options_file_arg != nullptr; }
3042   char* vm_options_file_arg()       { return _vm_options_file_arg; }
3043 
3044   void set_vm_options_file_arg(const char *vm_options_file_arg) {
3045     if (_vm_options_file_arg != nullptr) {
3046       os::free(_vm_options_file_arg);
3047     }
3048     _vm_options_file_arg = os::strdup_check_oom(vm_options_file_arg);
3049   }
3050 
3051   ~ScopedVMInitArgs() {
3052     if (_vm_options_file_arg != nullptr) {
3053       os::free(_vm_options_file_arg);
3054     }
3055     if (_args.options == nullptr) return;
3056     for (int i = 0; i < _args.nOptions; i++) {
3057       os::free(_args.options[i].optionString);
3058     }
3059     FREE_C_HEAP_ARRAY(JavaVMOption, _args.options);
3060   }
3061 
3062   // Insert options into this option list, to replace option at
3063   // vm_options_file_pos (-XX:VMOptionsFile)
3064   jint insert(const JavaVMInitArgs* args,
3065               const JavaVMInitArgs* args_to_insert,
3066               const int vm_options_file_pos) {
3067     assert(_args.options == nullptr, "shouldn't be set yet");
3068     assert(args_to_insert->nOptions != 0, "there should be args to insert");
3069     assert(vm_options_file_pos != -1, "vm_options_file_pos should be set");
3070 
3071     int length = args->nOptions + args_to_insert->nOptions - 1;
3072     // Construct new option array
3073     GrowableArrayCHeap<JavaVMOption, mtArguments> options(length);
3074     for (int i = 0; i < args->nOptions; i++) {
3075       if (i == vm_options_file_pos) {
3076         // insert the new options starting at the same place as the
3077         // -XX:VMOptionsFile option
3078         for (int j = 0; j < args_to_insert->nOptions; j++) {
3079           options.push(args_to_insert->options[j]);
3080         }
3081       } else {
3082         options.push(args->options[i]);
3083       }
3084     }
3085     // make into options array
3086     return set_args(&options);
3087   }
3088 };
3089 
3090 jint Arguments::parse_java_options_environment_variable(ScopedVMInitArgs* args) {
3091   return parse_options_environment_variable("_JAVA_OPTIONS", args);
3092 }
3093 
3094 jint Arguments::parse_java_tool_options_environment_variable(ScopedVMInitArgs* args) {
3095   return parse_options_environment_variable("JAVA_TOOL_OPTIONS", args);
3096 }
3097 
3098 static JavaVMOption* get_last_aotmode_arg(const JavaVMInitArgs* args) {
3099   for (int index = args->nOptions - 1; index >= 0; index--) {
3100     JavaVMOption* option = args->options + index;
3101     if (strstr(option->optionString, "-XX:AOTMode=") == option->optionString) {
3102       return option;
3103     }
3104   }
3105 
3106   return nullptr;
3107 }
3108 
3109 jint Arguments::parse_jdk_aot_vm_options_environment_variable(GrowableArrayCHeap<VMInitArgsGroup, mtArguments>* all_args,
3110                                                             ScopedVMInitArgs* jdk_aot_vm_options_args) {
3111   // Don't bother scanning all the args if this env variable is not set
3112   if (::getenv("JDK_AOT_VM_OPTIONS") == nullptr) {
3113     return JNI_OK;
3114   }
3115 
3116   // Scan backwards and find the last occurrence of -XX:AOTMode=xxx, which will decide the value
3117   // of AOTMode.
3118   JavaVMOption* option = nullptr;
3119   for (int i = all_args->length() - 1; i >= 0; i--) {
3120     if ((option = get_last_aotmode_arg(all_args->at(i)._args)) != nullptr) {
3121       break;
3122     }
3123   }
3124 
3125   if (option != nullptr) {
3126     // We have found the last -XX:AOTMode=xxx. At this point <option> has NOT been parsed yet,
3127     // so its value is not reflected inside the global variable AOTMode.
3128     if (strcmp(option->optionString, "-XX:AOTMode=create") != 0) {
3129       return JNI_OK; // Do not parse JDK_AOT_VM_OPTIONS
3130     }
3131   } else {
3132     // -XX:AOTMode is not specified in any of 4 options_args, let's check AOTMode,
3133     // which would have been set inside process_settings_file();
3134     if (AOTMode == nullptr || strcmp(AOTMode, "create") != 0) {
3135       return JNI_OK; // Do not parse JDK_AOT_VM_OPTIONS
3136     }
3137   }
3138 
3139   return parse_options_environment_variable("JDK_AOT_VM_OPTIONS", jdk_aot_vm_options_args);
3140 }
3141 
3142 jint Arguments::parse_options_environment_variable(const char* name,
3143                                                    ScopedVMInitArgs* vm_args) {
3144   char *buffer = ::getenv(name);
3145 
3146   // Don't check this environment variable if user has special privileges
3147   // (e.g. unix su command).
3148   if (buffer == nullptr || os::have_special_privileges()) {
3149     return JNI_OK;
3150   }
3151 
3152   if ((buffer = os::strdup(buffer)) == nullptr) {
3153     return JNI_ENOMEM;
3154   }
3155 
3156   jio_fprintf(defaultStream::error_stream(),
3157               "Picked up %s: %s\n", name, buffer);
3158 
3159   int retcode = parse_options_buffer(name, buffer, strlen(buffer), vm_args);
3160 
3161   os::free(buffer);
3162   return retcode;
3163 }
3164 
3165 jint Arguments::parse_vm_options_file(const char* file_name, ScopedVMInitArgs* vm_args) {
3166   // read file into buffer
3167   int fd = ::open(file_name, O_RDONLY);
3168   if (fd < 0) {
3169     jio_fprintf(defaultStream::error_stream(),
3170                 "Could not open options file '%s'\n",
3171                 file_name);
3172     return JNI_ERR;
3173   }
3174 
3175   struct stat stbuf;
3176   int retcode = os::stat(file_name, &stbuf);
3177   if (retcode != 0) {
3178     jio_fprintf(defaultStream::error_stream(),
3179                 "Could not stat options file '%s'\n",
3180                 file_name);
3181     ::close(fd);
3182     return JNI_ERR;
3183   }
3184 
3185   if (stbuf.st_size == 0) {
3186     // tell caller there is no option data and that is ok
3187     ::close(fd);
3188     return JNI_OK;
3189   }
3190 
3191   // '+ 1' for null termination even with max bytes
3192   size_t bytes_alloc = stbuf.st_size + 1;
3193 
3194   char *buf = NEW_C_HEAP_ARRAY_RETURN_NULL(char, bytes_alloc, mtArguments);
3195   if (nullptr == buf) {
3196     jio_fprintf(defaultStream::error_stream(),
3197                 "Could not allocate read buffer for options file parse\n");
3198     ::close(fd);
3199     return JNI_ENOMEM;
3200   }
3201 
3202   memset(buf, 0, bytes_alloc);
3203 
3204   // Fill buffer
3205   ssize_t bytes_read = ::read(fd, (void *)buf, (unsigned)bytes_alloc);
3206   ::close(fd);
3207   if (bytes_read < 0) {
3208     FREE_C_HEAP_ARRAY(char, buf);
3209     jio_fprintf(defaultStream::error_stream(),
3210                 "Could not read options file '%s'\n", file_name);
3211     return JNI_ERR;
3212   }
3213 
3214   if (bytes_read == 0) {
3215     // tell caller there is no option data and that is ok
3216     FREE_C_HEAP_ARRAY(char, buf);
3217     return JNI_OK;
3218   }
3219 
3220   retcode = parse_options_buffer(file_name, buf, bytes_read, vm_args);
3221 
3222   FREE_C_HEAP_ARRAY(char, buf);
3223   return retcode;
3224 }
3225 
3226 jint Arguments::parse_options_buffer(const char* name, char* buffer, const size_t buf_len, ScopedVMInitArgs* vm_args) {
3227   // Construct option array
3228   GrowableArrayCHeap<JavaVMOption, mtArguments> options(2);
3229 
3230   // some pointers to help with parsing
3231   char *buffer_end = buffer + buf_len;
3232   char *opt_hd = buffer;
3233   char *wrt = buffer;
3234   char *rd = buffer;
3235 
3236   // parse all options
3237   while (rd < buffer_end) {
3238     // skip leading white space from the input string
3239     while (rd < buffer_end && isspace((unsigned char) *rd)) {
3240       rd++;
3241     }
3242 
3243     if (rd >= buffer_end) {
3244       break;
3245     }
3246 
3247     // Remember this is where we found the head of the token.
3248     opt_hd = wrt;
3249 
3250     // Tokens are strings of non white space characters separated
3251     // by one or more white spaces.
3252     while (rd < buffer_end && !isspace((unsigned char) *rd)) {
3253       if (*rd == '\'' || *rd == '"') {      // handle a quoted string
3254         int quote = *rd;                    // matching quote to look for
3255         rd++;                               // don't copy open quote
3256         while (rd < buffer_end && *rd != quote) {
3257                                             // include everything (even spaces)
3258                                             // up until the close quote
3259           *wrt++ = *rd++;                   // copy to option string
3260         }
3261 
3262         if (rd < buffer_end) {
3263           rd++;                             // don't copy close quote
3264         } else {
3265                                             // did not see closing quote
3266           jio_fprintf(defaultStream::error_stream(),
3267                       "Unmatched quote in %s\n", name);
3268           return JNI_ERR;
3269         }
3270       } else {
3271         *wrt++ = *rd++;                     // copy to option string
3272       }
3273     }
3274 
3275     // steal a white space character and set it to null
3276     *wrt++ = '\0';
3277     // We now have a complete token
3278 
3279     JavaVMOption option;
3280     option.optionString = opt_hd;
3281     option.extraInfo = nullptr;
3282 
3283     options.append(option);                // Fill in option
3284 
3285     rd++;  // Advance to next character
3286   }
3287 
3288   // Fill out JavaVMInitArgs structure.
3289   return vm_args->set_args(&options);
3290 }
3291 
3292 #ifndef PRODUCT
3293 // Determine whether LogVMOutput should be implicitly turned on.
3294 static bool use_vm_log() {
3295   if (LogCompilation || !FLAG_IS_DEFAULT(LogFile) ||
3296       PrintCompilation || PrintInlining || PrintDependencies || PrintNativeNMethods ||
3297       PrintDebugInfo || PrintRelocations || PrintNMethods || PrintExceptionHandlers ||
3298       PrintAssembly || TraceDeoptimization ||
3299       (VerifyDependencies && FLAG_IS_CMDLINE(VerifyDependencies))) {
3300     return true;
3301   }
3302 
3303 #ifdef COMPILER1
3304   if (PrintC1Statistics) {
3305     return true;
3306   }
3307 #endif // COMPILER1
3308 
3309 #ifdef COMPILER2
3310   if (PrintOptoAssembly || PrintOptoStatistics) {
3311     return true;
3312   }
3313 #endif // COMPILER2
3314 
3315   return false;
3316 }
3317 
3318 #endif // PRODUCT
3319 
3320 bool Arguments::args_contains_vm_options_file_arg(const JavaVMInitArgs* args) {
3321   for (int index = 0; index < args->nOptions; index++) {
3322     const JavaVMOption* option = args->options + index;
3323     const char* tail;
3324     if (match_option(option, "-XX:VMOptionsFile=", &tail)) {
3325       return true;
3326     }
3327   }
3328   return false;
3329 }
3330 
3331 jint Arguments::insert_vm_options_file(const JavaVMInitArgs* args,
3332                                        const char* vm_options_file,
3333                                        const int vm_options_file_pos,
3334                                        ScopedVMInitArgs* vm_options_file_args,
3335                                        ScopedVMInitArgs* args_out) {
3336   jint code = parse_vm_options_file(vm_options_file, vm_options_file_args);
3337   if (code != JNI_OK) {
3338     return code;
3339   }
3340 
3341   if (vm_options_file_args->get()->nOptions < 1) {
3342     return JNI_OK;
3343   }
3344 
3345   if (args_contains_vm_options_file_arg(vm_options_file_args->get())) {
3346     jio_fprintf(defaultStream::error_stream(),
3347                 "A VM options file may not refer to a VM options file. "
3348                 "Specification of '-XX:VMOptionsFile=<file-name>' in the "
3349                 "options file '%s' in options container '%s' is an error.\n",
3350                 vm_options_file_args->vm_options_file_arg(),
3351                 vm_options_file_args->container_name());
3352     return JNI_EINVAL;
3353   }
3354 
3355   return args_out->insert(args, vm_options_file_args->get(),
3356                           vm_options_file_pos);
3357 }
3358 
3359 // Expand -XX:VMOptionsFile found in args_in as needed.
3360 // mod_args and args_out parameters may return values as needed.
3361 jint Arguments::expand_vm_options_as_needed(const JavaVMInitArgs* args_in,
3362                                             ScopedVMInitArgs* mod_args,
3363                                             JavaVMInitArgs** args_out) {
3364   jint code = match_special_option_and_act(args_in, mod_args);
3365   if (code != JNI_OK) {
3366     return code;
3367   }
3368 
3369   if (mod_args->is_set()) {
3370     // args_in contains -XX:VMOptionsFile and mod_args contains the
3371     // original options from args_in along with the options expanded
3372     // from the VMOptionsFile. Return a short-hand to the caller.
3373     *args_out = mod_args->get();
3374   } else {
3375     *args_out = (JavaVMInitArgs *)args_in;  // no changes so use args_in
3376   }
3377   return JNI_OK;
3378 }
3379 
3380 jint Arguments::match_special_option_and_act(const JavaVMInitArgs* args,
3381                                              ScopedVMInitArgs* args_out) {
3382   // Remaining part of option string
3383   const char* tail;
3384   ScopedVMInitArgs vm_options_file_args(args_out->container_name());
3385 
3386   for (int index = 0; index < args->nOptions; index++) {
3387     const JavaVMOption* option = args->options + index;
3388     if (match_option(option, "-XX:Flags=", &tail)) {
3389       Arguments::set_jvm_flags_file(tail);
3390       continue;
3391     }
3392     if (match_option(option, "-XX:VMOptionsFile=", &tail)) {
3393       if (vm_options_file_args.found_vm_options_file_arg()) {
3394         jio_fprintf(defaultStream::error_stream(),
3395                     "The option '%s' is already specified in the options "
3396                     "container '%s' so the specification of '%s' in the "
3397                     "same options container is an error.\n",
3398                     vm_options_file_args.vm_options_file_arg(),
3399                     vm_options_file_args.container_name(),
3400                     option->optionString);
3401         return JNI_EINVAL;
3402       }
3403       vm_options_file_args.set_vm_options_file_arg(option->optionString);
3404       // If there's a VMOptionsFile, parse that
3405       jint code = insert_vm_options_file(args, tail, index,
3406                                          &vm_options_file_args, args_out);
3407       if (code != JNI_OK) {
3408         return code;
3409       }
3410       args_out->set_vm_options_file_arg(vm_options_file_args.vm_options_file_arg());
3411       if (args_out->is_set()) {
3412         // The VMOptions file inserted some options so switch 'args'
3413         // to the new set of options, and continue processing which
3414         // preserves "last option wins" semantics.
3415         args = args_out->get();
3416         // The first option from the VMOptionsFile replaces the
3417         // current option.  So we back track to process the
3418         // replacement option.
3419         index--;
3420       }
3421       continue;
3422     }
3423     if (match_option(option, "-XX:+PrintVMOptions")) {
3424       PrintVMOptions = true;
3425       continue;
3426     }
3427     if (match_option(option, "-XX:-PrintVMOptions")) {
3428       PrintVMOptions = false;
3429       continue;
3430     }
3431     if (match_option(option, "-XX:+IgnoreUnrecognizedVMOptions")) {
3432       IgnoreUnrecognizedVMOptions = true;
3433       continue;
3434     }
3435     if (match_option(option, "-XX:-IgnoreUnrecognizedVMOptions")) {
3436       IgnoreUnrecognizedVMOptions = false;
3437       continue;
3438     }
3439     if (match_option(option, "-XX:+PrintFlagsInitial")) {
3440       JVMFlag::printFlags(tty, false);
3441       vm_exit(0);
3442     }
3443 
3444 #ifndef PRODUCT
3445     if (match_option(option, "-XX:+PrintFlagsWithComments")) {
3446       JVMFlag::printFlags(tty, true);
3447       vm_exit(0);
3448     }
3449 #endif
3450   }
3451   return JNI_OK;
3452 }
3453 
3454 static void print_options(const JavaVMInitArgs *args) {
3455   const char* tail;
3456   for (int index = 0; index < args->nOptions; index++) {
3457     const JavaVMOption *option = args->options + index;
3458     if (match_option(option, "-XX:", &tail)) {
3459       logOption(tail);
3460     }
3461   }
3462 }
3463 
3464 bool Arguments::handle_deprecated_print_gc_flags() {
3465   if (PrintGC) {
3466     log_warning(gc)("-XX:+PrintGC is deprecated. Will use -Xlog:gc instead.");
3467   }
3468   if (PrintGCDetails) {
3469     log_warning(gc)("-XX:+PrintGCDetails is deprecated. Will use -Xlog:gc* instead.");
3470   }
3471 
3472   if (_legacyGCLogging.lastFlag == 2) {
3473     // -Xloggc was used to specify a filename
3474     const char* gc_conf = PrintGCDetails ? "gc*" : "gc";
3475 
3476     LogTarget(Error, logging) target;
3477     LogStream errstream(target);
3478     return LogConfiguration::parse_log_arguments(_legacyGCLogging.file, gc_conf, nullptr, nullptr, &errstream);
3479   } else if (PrintGC || PrintGCDetails || (_legacyGCLogging.lastFlag == 1)) {
3480     LogConfiguration::configure_stdout(LogLevel::Info, !PrintGCDetails, LOG_TAGS(gc));
3481   }
3482   return true;
3483 }
3484 
3485 static void apply_debugger_ergo() {
3486 #ifdef ASSERT
3487   if (ReplayCompiles) {
3488     FLAG_SET_ERGO_IF_DEFAULT(UseDebuggerErgo, true);
3489   }
3490 
3491   if (UseDebuggerErgo) {
3492     // Turn on sub-flags
3493     FLAG_SET_ERGO_IF_DEFAULT(UseDebuggerErgo1, true);
3494     FLAG_SET_ERGO_IF_DEFAULT(UseDebuggerErgo2, true);
3495   }
3496 
3497   if (UseDebuggerErgo2) {
3498     // Debugging with limited number of CPUs
3499     FLAG_SET_ERGO_IF_DEFAULT(UseNUMA, false);
3500     FLAG_SET_ERGO_IF_DEFAULT(ConcGCThreads, 1);
3501     FLAG_SET_ERGO_IF_DEFAULT(ParallelGCThreads, 1);
3502     FLAG_SET_ERGO_IF_DEFAULT(CICompilerCount, 2);
3503   }
3504 #endif // ASSERT
3505 }
3506 
3507 // Parse entry point called from JNI_CreateJavaVM
3508 
3509 jint Arguments::parse(const JavaVMInitArgs* initial_cmd_args) {
3510   assert(verify_special_jvm_flags(false), "deprecated and obsolete flag table inconsistent");
3511   JVMFlag::check_all_flag_declarations();
3512 
3513   // If flag "-XX:Flags=flags-file" is used it will be the first option to be processed.
3514   const char* hotspotrc = ".hotspotrc";
3515   bool settings_file_specified = false;
3516   bool needs_hotspotrc_warning = false;
3517   ScopedVMInitArgs initial_vm_options_args("");
3518   ScopedVMInitArgs initial_java_tool_options_args("env_var='JAVA_TOOL_OPTIONS'");
3519   ScopedVMInitArgs initial_java_options_args("env_var='_JAVA_OPTIONS'");
3520   ScopedVMInitArgs initial_jdk_aot_vm_options_args("env_var='JDK_AOT_VM_OPTIONS'");
3521 
3522   // Pointers to current working set of containers
3523   JavaVMInitArgs* cur_cmd_args;
3524   JavaVMInitArgs* cur_vm_options_args;
3525   JavaVMInitArgs* cur_java_options_args;
3526   JavaVMInitArgs* cur_java_tool_options_args;
3527   JavaVMInitArgs* cur_jdk_aot_vm_options_args;
3528 
3529   // Containers for modified/expanded options
3530   ScopedVMInitArgs mod_cmd_args("cmd_line_args");
3531   ScopedVMInitArgs mod_vm_options_args("vm_options_args");
3532   ScopedVMInitArgs mod_java_tool_options_args("env_var='JAVA_TOOL_OPTIONS'");
3533   ScopedVMInitArgs mod_java_options_args("env_var='_JAVA_OPTIONS'");
3534   ScopedVMInitArgs mod_jdk_aot_vm_options_args("env_var='_JDK_AOT_VM_OPTIONS'");
3535 
3536   GrowableArrayCHeap<VMInitArgsGroup, mtArguments> all_args;
3537 
3538   jint code =
3539       parse_java_tool_options_environment_variable(&initial_java_tool_options_args);
3540   if (code != JNI_OK) {
3541     return code;
3542   }
3543 
3544   // Yet another environment variable: _JAVA_OPTIONS. This mimics the classic VM.
3545   // This is an undocumented feature.
3546   code = parse_java_options_environment_variable(&initial_java_options_args);
3547   if (code != JNI_OK) {
3548     return code;
3549   }
3550 
3551   // Parse the options in the /java.base/jdk/internal/vm/options resource, if present
3552   char *vmoptions = ClassLoader::lookup_vm_options();
3553   if (vmoptions != nullptr) {
3554     code = parse_options_buffer("vm options resource", vmoptions, strlen(vmoptions), &initial_vm_options_args);
3555     FREE_C_HEAP_ARRAY(char, vmoptions);
3556     if (code != JNI_OK) {
3557       return code;
3558     }
3559   }
3560 
3561   code = expand_vm_options_as_needed(initial_java_tool_options_args.get(),
3562                                      &mod_java_tool_options_args,
3563                                      &cur_java_tool_options_args);
3564   if (code != JNI_OK) {
3565     return code;
3566   }
3567 
3568   code = expand_vm_options_as_needed(initial_cmd_args,
3569                                      &mod_cmd_args,
3570                                      &cur_cmd_args);
3571   if (code != JNI_OK) {
3572     return code;
3573   }
3574 
3575   code = expand_vm_options_as_needed(initial_java_options_args.get(),
3576                                      &mod_java_options_args,
3577                                      &cur_java_options_args);
3578   if (code != JNI_OK) {
3579     return code;
3580   }
3581 
3582   code = expand_vm_options_as_needed(initial_vm_options_args.get(),
3583                                      &mod_vm_options_args,
3584                                      &cur_vm_options_args);
3585   if (code != JNI_OK) {
3586     return code;
3587   }
3588 
3589   const char* flags_file = Arguments::get_jvm_flags_file();
3590   settings_file_specified = (flags_file != nullptr);
3591 
3592   // Parse specified settings file (s) -- the effects are applied immediately into the JVM global flags.
3593   if (settings_file_specified) {
3594     if (!process_settings_file(flags_file, true,
3595                                IgnoreUnrecognizedVMOptions)) {
3596       return JNI_EINVAL;
3597     }
3598   } else {
3599 #ifdef ASSERT
3600     // Parse default .hotspotrc settings file
3601     if (!process_settings_file(".hotspotrc", false,
3602                                IgnoreUnrecognizedVMOptions)) {
3603       return JNI_EINVAL;
3604     }
3605 #else
3606     struct stat buf;
3607     if (os::stat(hotspotrc, &buf) == 0) {
3608       needs_hotspotrc_warning = true;
3609     }
3610 #endif
3611   }
3612 
3613   // The settings in the args are applied in this order to the the JVM global flags.
3614   // For historical reasons, the order is DIFFERENT than the scanning order of
3615   // the above expand_vm_options_as_needed() calls.
3616   all_args.append({cur_vm_options_args, JVMFlagOrigin::JIMAGE_RESOURCE});
3617   all_args.append({cur_java_tool_options_args, JVMFlagOrigin::ENVIRON_VAR});
3618   all_args.append({cur_cmd_args, JVMFlagOrigin::COMMAND_LINE});
3619   all_args.append({cur_java_options_args, JVMFlagOrigin::ENVIRON_VAR});
3620 
3621   // JDK_AOT_VM_OPTIONS are parsed only if -XX:AOTMode=create has been detected from all
3622   // the options that have been gathered above.
3623   code = parse_jdk_aot_vm_options_environment_variable(&all_args, &initial_jdk_aot_vm_options_args);
3624   if (code != JNI_OK) {
3625     return code;
3626   }
3627   code = expand_vm_options_as_needed(initial_jdk_aot_vm_options_args.get(),
3628                                      &mod_jdk_aot_vm_options_args,
3629                                      &cur_jdk_aot_vm_options_args);
3630   if (code != JNI_OK) {
3631     return code;
3632   }
3633 
3634   for (int index = 0; index < cur_jdk_aot_vm_options_args->nOptions; index++) {
3635     JavaVMOption* option = cur_jdk_aot_vm_options_args->options + index;
3636     const char* optionString = option->optionString;
3637     if (strstr(optionString, "-XX:AOTMode=") == optionString &&
3638         strcmp(optionString, "-XX:AOTMode=create") != 0) {
3639       jio_fprintf(defaultStream::error_stream(),
3640                   "Option %s cannot be specified in JDK_AOT_VM_OPTIONS\n", optionString);
3641       return JNI_ERR;
3642     }
3643   }
3644 
3645   all_args.append({cur_jdk_aot_vm_options_args, JVMFlagOrigin::ENVIRON_VAR});
3646 
3647   if (IgnoreUnrecognizedVMOptions) {
3648     // Note: unrecognized options in cur_vm_options_arg cannot be ignored. They are part of
3649     // the JDK so it shouldn't have bad options.
3650     cur_cmd_args->ignoreUnrecognized = true;
3651     cur_java_tool_options_args->ignoreUnrecognized = true;
3652     cur_java_options_args->ignoreUnrecognized = true;
3653     cur_jdk_aot_vm_options_args->ignoreUnrecognized = true;
3654   }
3655 
3656   if (PrintVMOptions) {
3657     // For historical reasons, options specified in cur_vm_options_arg and -XX:Flags are not printed.
3658     print_options(cur_java_tool_options_args);
3659     print_options(cur_cmd_args);
3660     print_options(cur_java_options_args);
3661     print_options(cur_jdk_aot_vm_options_args);
3662   }
3663 
3664   // Apply the settings in these args to the JVM global flags.
3665   jint result = parse_vm_init_args(&all_args);
3666 
3667   if (result != JNI_OK) {
3668     return result;
3669   }
3670 
3671   // Delay warning until here so that we've had a chance to process
3672   // the -XX:-PrintWarnings flag
3673   if (needs_hotspotrc_warning) {
3674     warning("%s file is present but has been ignored.  "
3675             "Run with -XX:Flags=%s to load the file.",
3676             hotspotrc, hotspotrc);
3677   }
3678 
3679   if (needs_module_property_warning) {
3680     warning("Ignoring system property options whose names match the '-Djdk.module.*'."
3681             " names that are reserved for internal use.");
3682   }
3683 
3684 #if defined(_ALLBSD_SOURCE) || defined(AIX)  // UseLargePages is not yet supported on BSD and AIX.
3685   UNSUPPORTED_OPTION(UseLargePages);
3686 #endif
3687 
3688 #if defined(AIX)
3689   UNSUPPORTED_OPTION_NULL(AllocateHeapAt);
3690 #endif
3691 
3692 #ifndef PRODUCT
3693   if (TraceBytecodesAt != 0) {
3694     TraceBytecodes = true;
3695   }
3696 #endif // PRODUCT
3697 
3698   if (ScavengeRootsInCode == 0) {
3699     if (!FLAG_IS_DEFAULT(ScavengeRootsInCode)) {
3700       warning("Forcing ScavengeRootsInCode non-zero");
3701     }
3702     ScavengeRootsInCode = 1;
3703   }
3704 
3705   if (!handle_deprecated_print_gc_flags()) {
3706     return JNI_EINVAL;
3707   }
3708 
3709   // Set object alignment values.
3710   set_object_alignment();
3711 
3712 #if !INCLUDE_CDS
3713   if (CDSConfig::is_dumping_static_archive() || RequireSharedSpaces) {
3714     jio_fprintf(defaultStream::error_stream(),
3715       "Shared spaces are not supported in this VM\n");
3716     return JNI_ERR;
3717   }
3718   if (DumpLoadedClassList != nullptr) {
3719     jio_fprintf(defaultStream::error_stream(),
3720       "DumpLoadedClassList is not supported in this VM\n");
3721     return JNI_ERR;
3722   }
3723   if ((CDSConfig::is_using_archive() && xshare_auto_cmd_line) ||
3724       log_is_enabled(Info, cds) || log_is_enabled(Info, aot)) {
3725     warning("Shared spaces are not supported in this VM");
3726     UseSharedSpaces = false;
3727     LogConfiguration::configure_stdout(LogLevel::Off, true, LOG_TAGS(cds));
3728     LogConfiguration::configure_stdout(LogLevel::Off, true, LOG_TAGS(aot));
3729   }
3730   no_shared_spaces("CDS Disabled");
3731 #endif // INCLUDE_CDS
3732 
3733   // Verify NMT arguments
3734   const NMT_TrackingLevel lvl = NMTUtil::parse_tracking_level(NativeMemoryTracking);
3735   if (lvl == NMT_unknown) {
3736     jio_fprintf(defaultStream::error_stream(),
3737                 "Syntax error, expecting -XX:NativeMemoryTracking=[off|summary|detail]\n");
3738     return JNI_ERR;
3739   }
3740   if (PrintNMTStatistics && lvl == NMT_off) {
3741     warning("PrintNMTStatistics is disabled, because native memory tracking is not enabled");
3742     FLAG_SET_DEFAULT(PrintNMTStatistics, false);
3743   }
3744 
3745   bool trace_dependencies = log_is_enabled(Debug, dependencies);
3746   if (trace_dependencies && VerifyDependencies) {
3747     warning("dependency logging results may be inflated by VerifyDependencies");
3748   }
3749 
3750   bool log_class_load_cause = log_is_enabled(Info, class, load, cause, native) ||
3751                               log_is_enabled(Info, class, load, cause);
3752   if (log_class_load_cause && LogClassLoadingCauseFor == nullptr) {
3753     warning("class load cause logging will not produce output without LogClassLoadingCauseFor");
3754   }
3755 
3756   apply_debugger_ergo();
3757 
3758   // The VMThread needs to stop now and then to execute these debug options.
3759   if ((HandshakeALot || SafepointALot) && FLAG_IS_DEFAULT(GuaranteedSafepointInterval)) {
3760     FLAG_SET_DEFAULT(GuaranteedSafepointInterval, 1000);
3761   }
3762 
3763   if (log_is_enabled(Info, arguments)) {
3764     LogStream st(Log(arguments)::info());
3765     Arguments::print_on(&st);
3766   }
3767 
3768   return JNI_OK;
3769 }
3770 
3771 void Arguments::set_compact_headers_flags() {
3772 #ifdef _LP64
3773   if (UseCompactObjectHeaders && FLAG_IS_CMDLINE(UseCompressedClassPointers) && !UseCompressedClassPointers) {
3774     warning("Compact object headers require compressed class pointers. Disabling compact object headers.");
3775     FLAG_SET_DEFAULT(UseCompactObjectHeaders, false);
3776   }
3777   if (UseCompactObjectHeaders && !UseObjectMonitorTable) {
3778     // If UseCompactObjectHeaders is on the command line, turn on UseObjectMonitorTable.
3779     if (FLAG_IS_CMDLINE(UseCompactObjectHeaders)) {
3780       FLAG_SET_DEFAULT(UseObjectMonitorTable, true);
3781 
3782       // If UseObjectMonitorTable is on the command line, turn off UseCompactObjectHeaders.
3783     } else if (FLAG_IS_CMDLINE(UseObjectMonitorTable)) {
3784       FLAG_SET_DEFAULT(UseCompactObjectHeaders, false);
3785       // If neither on the command line, the defaults are incompatible, but turn on UseObjectMonitorTable.
3786     } else {
3787       FLAG_SET_DEFAULT(UseObjectMonitorTable, true);
3788     }
3789   }
3790   if (UseCompactObjectHeaders && !UseCompressedClassPointers) {
3791     FLAG_SET_DEFAULT(UseCompressedClassPointers, true);
3792   }
3793 #endif
3794 }
3795 
3796 jint Arguments::apply_ergo() {
3797   // Set flags based on ergonomics.
3798   jint result = set_ergonomics_flags();
3799   if (result != JNI_OK) return result;
3800 
3801   // Set heap size based on available physical memory
3802   set_heap_size();
3803 
3804   GCConfig::arguments()->initialize();
3805 
3806   set_compact_headers_flags();
3807 
3808   if (UseCompressedClassPointers) {
3809     CompressedKlassPointers::pre_initialize();
3810   }
3811 
3812   CDSConfig::ergo_initialize();
3813 
3814   // Initialize Metaspace flags and alignments
3815   Metaspace::ergo_initialize();
3816 
3817   if (!StringDedup::ergo_initialize()) {
3818     return JNI_EINVAL;
3819   }
3820 
3821   // Set compiler flags after GC is selected and GC specific
3822   // flags (LoopStripMiningIter) are set.
3823   CompilerConfig::ergo_initialize();
3824 
3825   // Set bytecode rewriting flags
3826   set_bytecode_flags();
3827 
3828   // Set flags if aggressive optimization flags are enabled
3829   jint code = set_aggressive_opts_flags();
3830   if (code != JNI_OK) {
3831     return code;
3832   }
3833 
3834   if (FLAG_IS_DEFAULT(UseSecondarySupersTable)) {
3835     FLAG_SET_DEFAULT(UseSecondarySupersTable, VM_Version::supports_secondary_supers_table());
3836   } else if (UseSecondarySupersTable && !VM_Version::supports_secondary_supers_table()) {
3837     warning("UseSecondarySupersTable is not supported");
3838     FLAG_SET_DEFAULT(UseSecondarySupersTable, false);
3839   }
3840   if (!UseSecondarySupersTable) {
3841     FLAG_SET_DEFAULT(StressSecondarySupers, false);
3842     FLAG_SET_DEFAULT(VerifySecondarySupers, false);
3843   }
3844 
3845 #ifdef ZERO
3846   // Clear flags not supported on zero.
3847   FLAG_SET_DEFAULT(ProfileInterpreter, false);
3848 #endif // ZERO
3849 
3850   if (PrintAssembly && FLAG_IS_DEFAULT(DebugNonSafepoints)) {
3851     warning("PrintAssembly is enabled; turning on DebugNonSafepoints to gain additional output");
3852     DebugNonSafepoints = true;
3853   }
3854 
3855   if (FLAG_IS_CMDLINE(CompressedClassSpaceSize) && !UseCompressedClassPointers) {
3856     warning("Setting CompressedClassSpaceSize has no effect when compressed class pointers are not used");
3857   }
3858 
3859   // Treat the odd case where local verification is enabled but remote
3860   // verification is not as if both were enabled.
3861   if (BytecodeVerificationLocal && !BytecodeVerificationRemote) {
3862     log_info(verification)("Turning on remote verification because local verification is on");
3863     FLAG_SET_DEFAULT(BytecodeVerificationRemote, true);
3864   }
3865 
3866 #ifndef PRODUCT
3867   if (!LogVMOutput && FLAG_IS_DEFAULT(LogVMOutput)) {
3868     if (use_vm_log()) {
3869       LogVMOutput = true;
3870     }
3871   }
3872 #endif // PRODUCT
3873 
3874   if (PrintCommandLineFlags) {
3875     JVMFlag::printSetFlags(tty);
3876   }
3877 
3878 #if COMPILER2_OR_JVMCI
3879   if (!FLAG_IS_DEFAULT(EnableVectorSupport) && !EnableVectorSupport) {
3880     if (!FLAG_IS_DEFAULT(EnableVectorReboxing) && EnableVectorReboxing) {
3881       warning("Disabling EnableVectorReboxing since EnableVectorSupport is turned off.");
3882     }
3883     FLAG_SET_DEFAULT(EnableVectorReboxing, false);
3884 
3885     if (!FLAG_IS_DEFAULT(EnableVectorAggressiveReboxing) && EnableVectorAggressiveReboxing) {
3886       if (!EnableVectorReboxing) {
3887         warning("Disabling EnableVectorAggressiveReboxing since EnableVectorReboxing is turned off.");
3888       } else {
3889         warning("Disabling EnableVectorAggressiveReboxing since EnableVectorSupport is turned off.");
3890       }
3891     }
3892     FLAG_SET_DEFAULT(EnableVectorAggressiveReboxing, false);
3893   }
3894 #endif // COMPILER2_OR_JVMCI
3895 
3896 #ifdef COMPILER2
3897   if (!FLAG_IS_DEFAULT(UseLoopPredicate) && !UseLoopPredicate && UseProfiledLoopPredicate) {
3898     warning("Disabling UseProfiledLoopPredicate since UseLoopPredicate is turned off.");
3899     FLAG_SET_ERGO(UseProfiledLoopPredicate, false);
3900   }
3901 #endif // COMPILER2
3902 
3903   if (log_is_enabled(Info, perf, class, link)) {
3904     if (!UsePerfData) {
3905       warning("Disabling -Xlog:perf+class+link since UsePerfData is turned off.");
3906       LogConfiguration::disable_tags(false, LOG_TAGS(perf, class, link));
3907       assert(!log_is_enabled(Info, perf, class, link), "sanity");
3908     }
3909   }
3910 
3911   if (FLAG_IS_CMDLINE(DiagnoseSyncOnValueBasedClasses)) {
3912     if (DiagnoseSyncOnValueBasedClasses == ObjectSynchronizer::LOG_WARNING && !log_is_enabled(Info, valuebasedclasses)) {
3913       LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(valuebasedclasses));
3914     }
3915   }
3916   return JNI_OK;
3917 }
3918 
3919 jint Arguments::adjust_after_os() {
3920   if (UseNUMA) {
3921     if (UseParallelGC) {
3922       if (FLAG_IS_DEFAULT(MinHeapDeltaBytes)) {
3923          FLAG_SET_DEFAULT(MinHeapDeltaBytes, 64*M);
3924       }
3925     }
3926   }
3927   return JNI_OK;
3928 }
3929 
3930 int Arguments::PropertyList_count(SystemProperty* pl) {
3931   int count = 0;
3932   while(pl != nullptr) {
3933     count++;
3934     pl = pl->next();
3935   }
3936   return count;
3937 }
3938 
3939 // Return the number of readable properties.
3940 int Arguments::PropertyList_readable_count(SystemProperty* pl) {
3941   int count = 0;
3942   while(pl != nullptr) {
3943     if (pl->readable()) {
3944       count++;
3945     }
3946     pl = pl->next();
3947   }
3948   return count;
3949 }
3950 
3951 const char* Arguments::PropertyList_get_value(SystemProperty *pl, const char* key) {
3952   assert(key != nullptr, "just checking");
3953   SystemProperty* prop;
3954   for (prop = pl; prop != nullptr; prop = prop->next()) {
3955     if (strcmp(key, prop->key()) == 0) return prop->value();
3956   }
3957   return nullptr;
3958 }
3959 
3960 // Return the value of the requested property provided that it is a readable property.
3961 const char* Arguments::PropertyList_get_readable_value(SystemProperty *pl, const char* key) {
3962   assert(key != nullptr, "just checking");
3963   SystemProperty* prop;
3964   // Return the property value if the keys match and the property is not internal or
3965   // it's the special internal property "jdk.boot.class.path.append".
3966   for (prop = pl; prop != nullptr; prop = prop->next()) {
3967     if (strcmp(key, prop->key()) == 0) {
3968       if (!prop->internal()) {
3969         return prop->value();
3970       } else if (strcmp(key, "jdk.boot.class.path.append") == 0) {
3971         return prop->value();
3972       } else {
3973         // Property is internal and not jdk.boot.class.path.append so return null.
3974         return nullptr;
3975       }
3976     }
3977   }
3978   return nullptr;
3979 }
3980 
3981 void Arguments::PropertyList_add(SystemProperty** plist, SystemProperty *new_p) {
3982   SystemProperty* p = *plist;
3983   if (p == nullptr) {
3984     *plist = new_p;
3985   } else {
3986     while (p->next() != nullptr) {
3987       p = p->next();
3988     }
3989     p->set_next(new_p);
3990   }
3991 }
3992 
3993 void Arguments::PropertyList_add(SystemProperty** plist, const char* k, const char* v,
3994                                  bool writeable, bool internal) {
3995   if (plist == nullptr)
3996     return;
3997 
3998   SystemProperty* new_p = new SystemProperty(k, v, writeable, internal);
3999   PropertyList_add(plist, new_p);
4000 }
4001 
4002 void Arguments::PropertyList_add(SystemProperty *element) {
4003   PropertyList_add(&_system_properties, element);
4004 }
4005 
4006 // This add maintains unique property key in the list.
4007 void Arguments::PropertyList_unique_add(SystemProperty** plist, const char* k, const char* v,
4008                                         PropertyAppendable append, PropertyWriteable writeable,
4009                                         PropertyInternal internal) {
4010   if (plist == nullptr)
4011     return;
4012 
4013   // If property key exists and is writeable, then update with new value.
4014   // Trying to update a non-writeable property is silently ignored.
4015   SystemProperty* prop;
4016   for (prop = *plist; prop != nullptr; prop = prop->next()) {
4017     if (strcmp(k, prop->key()) == 0) {
4018       if (append == AppendProperty) {
4019         prop->append_writeable_value(v);
4020       } else {
4021         prop->set_writeable_value(v);
4022       }
4023       return;
4024     }
4025   }
4026 
4027   PropertyList_add(plist, k, v, writeable == WriteableProperty, internal == InternalProperty);
4028 }
4029 
4030 // Copies src into buf, replacing "%%" with "%" and "%p" with pid
4031 // Returns true if all of the source pointed by src has been copied over to
4032 // the destination buffer pointed by buf. Otherwise, returns false.
4033 // Notes:
4034 // 1. If the length (buflen) of the destination buffer excluding the
4035 // null terminator character is not long enough for holding the expanded
4036 // pid characters, it also returns false instead of returning the partially
4037 // expanded one.
4038 // 2. The passed in "buflen" should be large enough to hold the null terminator.
4039 bool Arguments::copy_expand_pid(const char* src, size_t srclen,
4040                                 char* buf, size_t buflen) {
4041   const char* p = src;
4042   char* b = buf;
4043   const char* src_end = &src[srclen];
4044   char* buf_end = &buf[buflen - 1];
4045 
4046   while (p < src_end && b < buf_end) {
4047     if (*p == '%') {
4048       switch (*(++p)) {
4049       case '%':         // "%%" ==> "%"
4050         *b++ = *p++;
4051         break;
4052       case 'p':  {       //  "%p" ==> current process id
4053         // buf_end points to the character before the last character so
4054         // that we could write '\0' to the end of the buffer.
4055         size_t buf_sz = buf_end - b + 1;
4056         int ret = jio_snprintf(b, buf_sz, "%d", os::current_process_id());
4057 
4058         // if jio_snprintf fails or the buffer is not long enough to hold
4059         // the expanded pid, returns false.
4060         if (ret < 0 || ret >= (int)buf_sz) {
4061           return false;
4062         } else {
4063           b += ret;
4064           assert(*b == '\0', "fail in copy_expand_pid");
4065           if (p == src_end && b == buf_end + 1) {
4066             // reach the end of the buffer.
4067             return true;
4068           }
4069         }
4070         p++;
4071         break;
4072       }
4073       default :
4074         *b++ = '%';
4075       }
4076     } else {
4077       *b++ = *p++;
4078     }
4079   }
4080   *b = '\0';
4081   return (p == src_end); // return false if not all of the source was copied
4082 }