1 /*
   2  * Copyright (c) 1998, 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/systemDictionary.hpp"
  27 #include "classfile/vmSymbols.hpp"
  28 #include "compiler/compileBroker.hpp"
  29 #include "oops/oop.inline.hpp"
  30 #include "runtime/init.hpp"
  31 #include "runtime/java.hpp"
  32 #include "runtime/javaCalls.hpp"
  33 #include "runtime/thread.inline.hpp"
  34 #include "runtime/threadCritical.hpp"
  35 #include "utilities/events.hpp"
  36 #include "utilities/exceptions.hpp"
  37 
  38 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
  39 
  40 // Implementation of ThreadShadow
  41 void check_ThreadShadow() {
  42   const ByteSize offset1 = byte_offset_of(ThreadShadow, _pending_exception);
  43   const ByteSize offset2 = Thread::pending_exception_offset();
  44   if (offset1 != offset2) fatal("ThreadShadow::_pending_exception is not positioned correctly");
  45 }
  46 
  47 
  48 void ThreadShadow::set_pending_exception(oop exception, const char* file, int line) {
  49   assert(exception != NULL && exception->is_oop(), "invalid exception oop");
  50   _pending_exception = exception;
  51   _exception_file    = file;
  52   _exception_line    = line;
  53 }
  54 
  55 void ThreadShadow::clear_pending_exception() {
  56   if (TraceClearedExceptions) {
  57     if (_pending_exception != NULL) {
  58       tty->print_cr("Thread::clear_pending_exception: cleared exception:");
  59       _pending_exception->print();
  60     }
  61   }
  62   _pending_exception = NULL;
  63   _exception_file    = NULL;
  64   _exception_line    = 0;
  65 }
  66 // Implementation of Exceptions
  67 
  68 bool Exceptions::special_exception(Thread* thread, const char* file, int line, Handle h_exception) {
  69   // bootstrapping check
  70   if (!Universe::is_fully_initialized()) {
  71    vm_exit_during_initialization(h_exception);
  72    ShouldNotReachHere();
  73   }
  74 
  75 #ifdef ASSERT
  76   // Check for trying to throw stack overflow before initialization is complete
  77   // to prevent infinite recursion trying to initialize stack overflow without
  78   // adequate stack space.
  79   // This can happen with stress testing a large value of StackShadowPages
  80   if (h_exception()->klass() == SystemDictionary::StackOverflowError_klass()) {
  81     InstanceKlass* ik = InstanceKlass::cast(h_exception->klass());
  82     assert(ik->is_initialized(),
  83            "need to increase min_stack_allowed calculation");
  84   }
  85 #endif // ASSERT
  86 
  87   if (thread->is_VM_thread()
  88       || thread->is_Compiler_thread()
  89       || DumpSharedSpaces ) {
  90     // We do not care what kind of exception we get for the vm-thread or a thread which
  91     // is compiling.  We just install a dummy exception object
  92     //
  93     // We also cannot throw a proper exception when dumping, because we cannot run
  94     // Java bytecodes now. A dummy exception will suffice.
  95     thread->set_pending_exception(Universe::vm_exception(), file, line);
  96     return true;
  97   }
  98 
  99   return false;
 100 }
 101 
 102 bool Exceptions::special_exception(Thread* thread, const char* file, int line, Symbol* h_name, const char* message) {
 103   // bootstrapping check
 104   if (!Universe::is_fully_initialized()) {
 105     if (h_name == NULL) {
 106       // atleast an informative message.
 107       vm_exit_during_initialization("Exception", message);
 108     } else {
 109       vm_exit_during_initialization(h_name, message);
 110     }
 111     ShouldNotReachHere();
 112   }
 113 
 114   if (thread->is_VM_thread()
 115       || thread->is_Compiler_thread()
 116       || DumpSharedSpaces ) {
 117     // We do not care what kind of exception we get for the vm-thread or a thread which
 118     // is compiling.  We just install a dummy exception object
 119     //
 120     // We also cannot throw a proper exception when dumping, because we cannot run
 121     // Java bytecodes now. A dummy exception will suffice.
 122     thread->set_pending_exception(Universe::vm_exception(), file, line);
 123     return true;
 124   }
 125   return false;
 126 }
 127 
 128 // This method should only be called from generated code,
 129 // therefore the exception oop should be in the oopmap.
 130 void Exceptions::_throw_oop(Thread* thread, const char* file, int line, oop exception) {
 131   assert(exception != NULL, "exception should not be NULL");
 132   Handle h_exception = Handle(thread, exception);
 133   _throw(thread, file, line, h_exception);
 134 }
 135 
 136 void Exceptions::_throw(Thread* thread, const char* file, int line, Handle h_exception, const char* message) {
 137   ResourceMark rm;
 138   assert(h_exception() != NULL, "exception should not be NULL");
 139 
 140   // tracing (do this up front - so it works during boot strapping)
 141   if (TraceExceptions) {
 142     ttyLocker ttyl;
 143     tty->print_cr("Exception <%s%s%s> (" INTPTR_FORMAT ") \n"
 144                   "thrown [%s, line %d]\nfor thread " INTPTR_FORMAT,
 145                   h_exception->print_value_string(),
 146                   message ? ": " : "", message ? message : "",
 147                   (address)h_exception(), file, line, thread);
 148   }
 149   // for AbortVMOnException flag
 150   NOT_PRODUCT(Exceptions::debug_check_abort(h_exception, message));
 151 
 152   // Check for special boot-strapping/vm-thread handling
 153   if (special_exception(thread, file, line, h_exception)) {
 154     return;
 155   }
 156 
 157   if (h_exception->is_a(SystemDictionary::OutOfMemoryError_klass())) {
 158     count_out_of_memory_exceptions(h_exception);
 159   }
 160 
 161   assert(h_exception->is_a(SystemDictionary::Throwable_klass()), "exception is not a subclass of java/lang/Throwable");
 162 
 163   // set the pending exception
 164   thread->set_pending_exception(h_exception(), file, line);
 165 
 166   // vm log
 167   Events::log_exception(thread, "Exception <%s%s%s> (" INTPTR_FORMAT ") thrown at [%s, line %d]",
 168                         h_exception->print_value_string(), message ? ": " : "", message ? message : "",
 169                         (address)h_exception(), file, line);
 170 }
 171 
 172 
 173 void Exceptions::_throw_msg(Thread* thread, const char* file, int line, Symbol* name, const char* message,
 174                             Handle h_loader, Handle h_protection_domain) {
 175   // Check for special boot-strapping/vm-thread handling
 176   if (special_exception(thread, file, line, name, message)) return;
 177   // Create and throw exception
 178   Handle h_cause(thread, NULL);
 179   Handle h_exception = new_exception(thread, name, message, h_cause, h_loader, h_protection_domain);
 180   _throw(thread, file, line, h_exception, message);
 181 }
 182 
 183 void Exceptions::_throw_msg_cause(Thread* thread, const char* file, int line, Symbol* name, const char* message, Handle h_cause,
 184                                   Handle h_loader, Handle h_protection_domain) {
 185   // Check for special boot-strapping/vm-thread handling
 186   if (special_exception(thread, file, line, name, message)) return;
 187   // Create and throw exception and init cause
 188   Handle h_exception = new_exception(thread, name, message, h_cause, h_loader, h_protection_domain);
 189   _throw(thread, file, line, h_exception, message);
 190 }
 191 
 192 void Exceptions::_throw_cause(Thread* thread, const char* file, int line, Symbol* name, Handle h_cause,
 193                               Handle h_loader, Handle h_protection_domain) {
 194   // Check for special boot-strapping/vm-thread handling
 195   if (special_exception(thread, file, line, h_cause)) return;
 196   // Create and throw exception
 197   Handle h_exception = new_exception(thread, name, h_cause, h_loader, h_protection_domain);
 198   _throw(thread, file, line, h_exception, NULL);
 199 }
 200 
 201 void Exceptions::_throw_args(Thread* thread, const char* file, int line, Symbol* name, Symbol* signature, JavaCallArguments *args) {
 202   // Check for special boot-strapping/vm-thread handling
 203   if (special_exception(thread, file, line, name, NULL)) return;
 204   // Create and throw exception
 205   Handle h_loader(thread, NULL);
 206   Handle h_prot(thread, NULL);
 207   Handle exception = new_exception(thread, name, signature, args, h_loader, h_prot);
 208   _throw(thread, file, line, exception);
 209 }
 210 
 211 
 212 // Methods for default parameters.
 213 // NOTE: These must be here (and not in the header file) because of include circularities.
 214 void Exceptions::_throw_msg_cause(Thread* thread, const char* file, int line, Symbol* name, const char* message, Handle h_cause) {
 215   _throw_msg_cause(thread, file, line, name, message, h_cause, Handle(thread, NULL), Handle(thread, NULL));
 216 }
 217 void Exceptions::_throw_msg(Thread* thread, const char* file, int line, Symbol* name, const char* message) {
 218   _throw_msg(thread, file, line, name, message, Handle(thread, NULL), Handle(thread, NULL));
 219 }
 220 void Exceptions::_throw_cause(Thread* thread, const char* file, int line, Symbol* name, Handle h_cause) {
 221   _throw_cause(thread, file, line, name, h_cause, Handle(thread, NULL), Handle(thread, NULL));
 222 }
 223 
 224 
 225 void Exceptions::throw_stack_overflow_exception(Thread* THREAD, const char* file, int line, methodHandle method) {
 226   Handle exception;
 227   if (!THREAD->has_pending_exception()) {
 228     Klass* k = SystemDictionary::StackOverflowError_klass();
 229     oop e = InstanceKlass::cast(k)->allocate_instance(CHECK);
 230     exception = Handle(THREAD, e);  // fill_in_stack trace does gc
 231     assert(InstanceKlass::cast(k)->is_initialized(), "need to increase min_stack_allowed calculation");
 232     if (StackTraceInThrowable) {
 233       java_lang_Throwable::fill_in_stack_trace(exception, method());
 234     }
 235     // Increment counter for hs_err file reporting
 236     Atomic::inc(&Exceptions::_stack_overflow_errors);
 237   } else {
 238     // if prior exception, throw that one instead
 239     exception = Handle(THREAD, THREAD->pending_exception());
 240   }
 241   _throw(THREAD, file, line, exception);
 242 }
 243 
 244 void Exceptions::fthrow(Thread* thread, const char* file, int line, Symbol* h_name, const char* format, ...) {
 245   const int max_msg_size = 1024;
 246   va_list ap;
 247   va_start(ap, format);
 248   char msg[max_msg_size];
 249   vsnprintf(msg, max_msg_size, format, ap);
 250   msg[max_msg_size-1] = '\0';
 251   va_end(ap);
 252   _throw_msg(thread, file, line, h_name, msg);
 253 }
 254 
 255 
 256 // Creates an exception oop, calls the <init> method with the given signature.
 257 // and returns a Handle
 258 Handle Exceptions::new_exception(Thread *thread, Symbol* name,
 259                                  Symbol* signature, JavaCallArguments *args,
 260                                  Handle h_loader, Handle h_protection_domain) {
 261   assert(Universe::is_fully_initialized(),
 262     "cannot be called during initialization");
 263   assert(thread->is_Java_thread(), "can only be called by a Java thread");
 264   assert(!thread->has_pending_exception(), "already has exception");
 265 
 266   Handle h_exception;
 267 
 268   // Resolve exception klass
 269   Klass* ik = SystemDictionary::resolve_or_fail(name, h_loader, h_protection_domain, true, thread);
 270   instanceKlassHandle klass(thread, ik);
 271 
 272   if (!thread->has_pending_exception()) {
 273     assert(klass.not_null(), "klass must exist");
 274     // We are about to create an instance - so make sure that klass is initialized
 275     klass->initialize(thread);
 276     if (!thread->has_pending_exception()) {
 277       // Allocate new exception
 278       h_exception = klass->allocate_instance_handle(thread);
 279       if (!thread->has_pending_exception()) {
 280         JavaValue result(T_VOID);
 281         args->set_receiver(h_exception);
 282         // Call constructor
 283         JavaCalls::call_special(&result, klass,
 284                                          vmSymbols::object_initializer_name(),
 285                                          signature,
 286                                          args,
 287                                          thread);
 288       }
 289     }
 290   }
 291 
 292   // Check if another exception was thrown in the process, if so rethrow that one
 293   if (thread->has_pending_exception()) {
 294     h_exception = Handle(thread, thread->pending_exception());
 295     thread->clear_pending_exception();
 296   }
 297   return h_exception;
 298 }
 299 
 300 // Creates an exception oop, calls the <init> method with the given signature.
 301 // and returns a Handle
 302 // Initializes the cause if cause non-null
 303 Handle Exceptions::new_exception(Thread *thread, Symbol* name,
 304                                  Symbol* signature, JavaCallArguments *args,
 305                                  Handle h_cause,
 306                                  Handle h_loader, Handle h_protection_domain) {
 307   Handle h_exception = new_exception(thread, name, signature, args, h_loader, h_protection_domain);
 308 
 309   // Future: object initializer should take a cause argument
 310   if (h_cause.not_null()) {
 311     assert(h_cause->is_a(SystemDictionary::Throwable_klass()),
 312         "exception cause is not a subclass of java/lang/Throwable");
 313     JavaValue result1(T_OBJECT);
 314     JavaCallArguments args1;
 315     args1.set_receiver(h_exception);
 316     args1.push_oop(h_cause);
 317     JavaCalls::call_virtual(&result1, h_exception->klass(),
 318                                       vmSymbols::initCause_name(),
 319                                       vmSymbols::throwable_throwable_signature(),
 320                                       &args1,
 321                                       thread);
 322   }
 323 
 324   // Check if another exception was thrown in the process, if so rethrow that one
 325   if (thread->has_pending_exception()) {
 326     h_exception = Handle(thread, thread->pending_exception());
 327     thread->clear_pending_exception();
 328   }
 329   return h_exception;
 330 }
 331 
 332 // Convenience method. Calls either the <init>() or <init>(Throwable) method when
 333 // creating a new exception
 334 Handle Exceptions::new_exception(Thread* thread, Symbol* name,
 335                                  Handle h_cause,
 336                                  Handle h_loader, Handle h_protection_domain,
 337                                  ExceptionMsgToUtf8Mode to_utf8_safe) {
 338   JavaCallArguments args;
 339   Symbol* signature = NULL;
 340   if (h_cause.is_null()) {
 341     signature = vmSymbols::void_method_signature();
 342   } else {
 343     signature = vmSymbols::throwable_void_signature();
 344     args.push_oop(h_cause);
 345   }
 346   return new_exception(thread, name, signature, &args, h_loader, h_protection_domain);
 347 }
 348 
 349 // Convenience method. Calls either the <init>() or <init>(String) method when
 350 // creating a new exception
 351 Handle Exceptions::new_exception(Thread* thread, Symbol* name,
 352                                  const char* message, Handle h_cause,
 353                                  Handle h_loader, Handle h_protection_domain,
 354                                  ExceptionMsgToUtf8Mode to_utf8_safe) {
 355   JavaCallArguments args;
 356   Symbol* signature = NULL;
 357   if (message == NULL) {
 358     signature = vmSymbols::void_method_signature();
 359   } else {
 360     // We want to allocate storage, but we can't do that if there's
 361     // a pending exception, so we preserve any pending exception
 362     // around the allocation.
 363     // If we get an exception from the allocation, prefer that to
 364     // the exception we are trying to build, or the pending exception.
 365     // This is sort of like what PRESERVE_EXCEPTION_MARK does, except
 366     // for the preferencing and the early returns.
 367     Handle incoming_exception(thread, NULL);
 368     if (thread->has_pending_exception()) {
 369       incoming_exception = Handle(thread, thread->pending_exception());
 370       thread->clear_pending_exception();
 371     }
 372     Handle msg;
 373     if (to_utf8_safe == safe_to_utf8) {
 374       // Make a java UTF8 string.
 375       msg = java_lang_String::create_from_str(message, thread);
 376     } else {
 377       // Make a java string keeping the encoding scheme of the original string.
 378       msg = java_lang_String::create_from_platform_dependent_str(message, thread);
 379     }
 380     if (thread->has_pending_exception()) {
 381       Handle exception(thread, thread->pending_exception());
 382       thread->clear_pending_exception();
 383       return exception;
 384     }
 385     if (incoming_exception.not_null()) {
 386       return incoming_exception;
 387     }
 388     args.push_oop(msg);
 389     signature = vmSymbols::string_void_signature();
 390   }
 391   return new_exception(thread, name, signature, &args, h_cause, h_loader, h_protection_domain);
 392 }
 393 
 394 // Another convenience method that creates handles for null class loaders and
 395 // protection domains and null causes.
 396 // If the last parameter 'to_utf8_mode' is safe_to_utf8,
 397 // it means we can safely ignore the encoding scheme of the message string and
 398 // convert it directly to a java UTF8 string. Otherwise, we need to take the
 399 // encoding scheme of the string into account. One thing we should do at some
 400 // point is to push this flag down to class java_lang_String since other
 401 // classes may need similar functionalities.
 402 Handle Exceptions::new_exception(Thread* thread, Symbol* name,
 403                                  const char* message,
 404                                  ExceptionMsgToUtf8Mode to_utf8_safe) {
 405 
 406   Handle       h_loader(thread, NULL);
 407   Handle       h_prot(thread, NULL);
 408   Handle       h_cause(thread, NULL);
 409   return Exceptions::new_exception(thread, name, message, h_cause, h_loader,
 410                                    h_prot, to_utf8_safe);
 411 }
 412 
 413 
 414 // Exception counting for hs_err file
 415 volatile int Exceptions::_stack_overflow_errors = 0;
 416 volatile int Exceptions::_out_of_memory_error_java_heap_errors = 0;
 417 volatile int Exceptions::_out_of_memory_error_metaspace_errors = 0;
 418 volatile int Exceptions::_out_of_memory_error_class_metaspace_errors = 0;
 419 
 420 void Exceptions::count_out_of_memory_exceptions(Handle exception) {
 421   if (exception() == Universe::out_of_memory_error_metaspace()) {
 422      Atomic::inc(&_out_of_memory_error_metaspace_errors);
 423   } else if (exception() == Universe::out_of_memory_error_class_metaspace()) {
 424      Atomic::inc(&_out_of_memory_error_class_metaspace_errors);
 425   } else {
 426      // everything else reported as java heap OOM
 427      Atomic::inc(&_out_of_memory_error_java_heap_errors);
 428   }
 429 }
 430 
 431 void print_oom_count(outputStream* st, const char *err, int count) {
 432   if (count > 0) {
 433     st->print_cr("OutOfMemoryError %s=%d", err, count);
 434   }
 435 }
 436 
 437 bool Exceptions::has_exception_counts() {
 438   return (_stack_overflow_errors + _out_of_memory_error_java_heap_errors +
 439          _out_of_memory_error_metaspace_errors + _out_of_memory_error_class_metaspace_errors) > 0;
 440 }
 441 
 442 void Exceptions::print_exception_counts_on_error(outputStream* st) {
 443   print_oom_count(st, "java_heap_errors", _out_of_memory_error_java_heap_errors);
 444   print_oom_count(st, "metaspace_errors", _out_of_memory_error_metaspace_errors);
 445   print_oom_count(st, "class_metaspace_errors", _out_of_memory_error_class_metaspace_errors);
 446   if (_stack_overflow_errors > 0) {
 447     st->print_cr("StackOverflowErrors=%d", _stack_overflow_errors);
 448   }
 449 }
 450 
 451 // Implementation of ExceptionMark
 452 
 453 ExceptionMark::ExceptionMark(Thread*& thread) {
 454   thread     = Thread::current();
 455   _thread    = thread;
 456   if (_thread->has_pending_exception()) {
 457     oop exception = _thread->pending_exception();
 458     _thread->clear_pending_exception(); // Needed to avoid infinite recursion
 459     exception->print();
 460     fatal("ExceptionMark constructor expects no pending exceptions");
 461   }
 462 }
 463 
 464 
 465 ExceptionMark::~ExceptionMark() {
 466   if (_thread->has_pending_exception()) {
 467     Handle exception(_thread, _thread->pending_exception());
 468     _thread->clear_pending_exception(); // Needed to avoid infinite recursion
 469     if (is_init_completed()) {
 470       exception->print();
 471       fatal("ExceptionMark destructor expects no pending exceptions");
 472     } else {
 473       vm_exit_during_initialization(exception);
 474     }
 475   }
 476 }
 477 
 478 // ----------------------------------------------------------------------------------------
 479 
 480 #ifndef PRODUCT
 481 // caller frees value_string if necessary
 482 void Exceptions::debug_check_abort(const char *value_string, const char* message) {
 483   if (AbortVMOnException != NULL && value_string != NULL &&
 484       strstr(value_string, AbortVMOnException)) {
 485     if (AbortVMOnExceptionMessage == NULL || message == NULL ||
 486         strcmp(message, AbortVMOnExceptionMessage) == 0) {
 487       fatal(err_msg("Saw %s, aborting", value_string));
 488     }
 489   }
 490 }
 491 
 492 void Exceptions::debug_check_abort(Handle exception, const char* message) {
 493   if (AbortVMOnException != NULL) {
 494     ResourceMark rm;
 495     if (message == NULL && exception->is_a(SystemDictionary::Throwable_klass())) {
 496       oop msg = java_lang_Throwable::message(exception);
 497       if (msg != NULL) {
 498         message = java_lang_String::as_utf8_string(msg);
 499       }
 500     }
 501     debug_check_abort(InstanceKlass::cast(exception()->klass())->external_name(), message);
 502   }
 503 }
 504 #endif