libjava/prims.cc

   1 // prims.cc - Code for core of runtime environment.
   2
   3 /* Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005  Free Software Foundation
   4
   5    This file is part of libgcj.
   6
   7 This software is copyrighted work licensed under the terms of the
   8 Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
   9 details.  */
  10
  11 #include <config.h>
  12 #include <platform.h>
  13
  14 #include <stdlib.h>
  15 #include <stdarg.h>
  16 #include <stdio.h>
  17 #include <string.h>
  18 #include <signal.h>
  19
  20 #ifdef HAVE_UNISTD_H
  21 #include <unistd.h>
  22 #endif
  23
  24 #include <gcj/cni.h>
  25 #include <jvm.h>
  26 #include <java-signal.h>
  27 #include <java-threads.h>
  28 #include <java-interp.h>
  29
  30 #ifdef ENABLE_JVMPI
  31 #include <jvmpi.h>
  32 #include <java/lang/ThreadGroup.h>
  33 #endif
  34
  35 #ifndef DISABLE_GETENV_PROPERTIES
  36 #include <ctype.h>
  37 #include <java-props.h>
  38 #define PROCESS_GCJ_PROPERTIES process_gcj_properties()
  39 #else
  40 #define PROCESS_GCJ_PROPERTIES
  41 #endif // DISABLE_GETENV_PROPERTIES
  42
  43 #include <java/lang/Class.h>
  44 #include <java/lang/ClassLoader.h>
  45 #include <java/lang/Runtime.h>
  46 #include <java/lang/String.h>
  47 #include <java/lang/Thread.h>
  48 #include <java/lang/ThreadGroup.h>
  49 #include <java/lang/ArrayIndexOutOfBoundsException.h>
  50 #include <java/lang/ArithmeticException.h>
  51 #include <java/lang/ClassFormatError.h>
  52 #include <java/lang/InternalError.h>
  53 #include <java/lang/NegativeArraySizeException.h>
  54 #include <java/lang/NullPointerException.h>
  55 #include <java/lang/OutOfMemoryError.h>
  56 #include <java/lang/System.h>
  57 #include <java/lang/VMThrowable.h>
  58 #include <java/lang/VMClassLoader.h>
  59 #include <java/lang/reflect/Modifier.h>
  60 #include <java/io/PrintStream.h>
  61 #include <java/lang/UnsatisfiedLinkError.h>
  62 #include <java/lang/VirtualMachineError.h>
  63 #include <gnu/gcj/runtime/ExtensionClassLoader.h>
  64 #include <gnu/gcj/runtime/FinalizerThread.h>
  65 #include <execution.h>
  66 #include <gnu/java/lang/MainThread.h>
  67
  68 #ifdef USE_LTDL
  69 #include <ltdl.h>
  70 #endif
  71
  72 // Execution engine for compiled code.
  73 _Jv_CompiledEngine _Jv_soleCompiledEngine;
  74
  75 // We allocate a single OutOfMemoryError exception which we keep
  76 // around for use if we run out of memory.
  77 static java::lang::OutOfMemoryError *no_memory;
  78
  79 // Number of bytes in largest array object we create.  This could be
  80 // increased to the largest size_t value, so long as the appropriate
  81 // functions are changed to take a size_t argument instead of jint.
  82 #define MAX_OBJECT_SIZE ((1<<31) - 1)
  83
  84 // Properties set at compile time.
  85 const char **_Jv_Compiler_Properties = NULL;
  86 int _Jv_Properties_Count = 0;
  87
  88 #ifndef DISABLE_GETENV_PROPERTIES
  89 // Property key/value pairs.
  90 property_pair *_Jv_Environment_Properties;
  91 #endif
  92
  93 // Stash the argv pointer to benefit native libraries that need it.
  94 const char **_Jv_argv;
  95 int _Jv_argc;
  96
  97 // Argument support.
  98 int
  99 _Jv_GetNbArgs (void)
 100 {
 101   // _Jv_argc is 0 if not explicitly initialized.
 102   return _Jv_argc;
 103 }
 104
 105 const char *
 106 _Jv_GetSafeArg (int index)
 107 {
 108   if (index >=0 && index < _Jv_GetNbArgs ())
 109     return _Jv_argv[index];
 110   else
 111     return "";
 112 }
 113
 114 void
 115 _Jv_SetArgs (int argc, const char **argv)
 116 {
 117   _Jv_argc = argc;
 118   _Jv_argv = argv;
 119 }
 120
 121 #ifdef ENABLE_JVMPI
 122 // Pointer to JVMPI notification functions.
 123 void (*_Jv_JVMPI_Notify_OBJECT_ALLOC) (JVMPI_Event *event);
 124 void (*_Jv_JVMPI_Notify_THREAD_START) (JVMPI_Event *event);
 125 void (*_Jv_JVMPI_Notify_THREAD_END) (JVMPI_Event *event);
 126 #endif
 127 \f
 128
 129 #if defined (HANDLE_SEGV) || defined(HANDLE_FPE)
 130 /* Unblock a signal.  Unless we do this, the signal may only be sent
 131    once.  */
 132 static void
 133 unblock_signal (int signum __attribute__ ((__unused__)))
 134 {
 135 #ifdef _POSIX_VERSION
 136   sigset_t sigs;
 137
 138   sigemptyset (&sigs);
 139   sigaddset (&sigs, signum);
 140   sigprocmask (SIG_UNBLOCK, &sigs, NULL);
 141 #endif
 142 }
 143 #endif
 144
 145 #ifdef HANDLE_SEGV
 146 SIGNAL_HANDLER (catch_segv)
 147 {
 148   unblock_signal (SIGSEGV);
 149   MAKE_THROW_FRAME (nullp);
 150   java::lang::NullPointerException *nullp
 151     = new java::lang::NullPointerException;
 152   throw nullp;
 153 }
 154 #endif
 155
 156 #ifdef HANDLE_FPE
 157 SIGNAL_HANDLER (catch_fpe)
 158 {
 159   unblock_signal (SIGFPE);
 160 #ifdef HANDLE_DIVIDE_OVERFLOW
 161   HANDLE_DIVIDE_OVERFLOW;
 162 #else
 163   MAKE_THROW_FRAME (arithexception);
 164 #endif
 165   java::lang::ArithmeticException *arithexception
 166     = new java::lang::ArithmeticException (JvNewStringLatin1 ("/ by zero"));
 167   throw arithexception;
 168 }
 169 #endif
 170
 171 \f
 172
 173 jboolean
 174 _Jv_equalUtf8Consts (const Utf8Const* a, const Utf8Const *b)
 175 {
 176   int len;
 177   const _Jv_ushort *aptr, *bptr;
 178   if (a == b)
 179     return true;
 180   if (a->hash != b->hash)
 181     return false;
 182   len = a->length;
 183   if (b->length != len)
 184     return false;
 185   aptr = (const _Jv_ushort *)a->data;
 186   bptr = (const _Jv_ushort *)b->data;
 187   len = (len + 1) >> 1;
 188   while (--len >= 0)
 189     if (*aptr++ != *bptr++)
 190       return false;
 191   return true;
 192 }
 193
 194 /* True iff A is equal to STR.
 195    HASH is STR->hashCode().
 196 */
 197
 198 jboolean
 199 _Jv_equal (Utf8Const* a, jstring str, jint hash)
 200 {
 201   if (a->hash != (_Jv_ushort) hash)
 202     return false;
 203   jint len = str->length();
 204   jint i = 0;
 205   jchar *sptr = _Jv_GetStringChars (str);
 206   unsigned char* ptr = (unsigned char*) a->data;
 207   unsigned char* limit = ptr + a->length;
 208   for (;; i++, sptr++)
 209     {
 210       int ch = UTF8_GET (ptr, limit);
 211       if (i == len)
 212         return ch < 0;
 213       if (ch != *sptr)
 214         return false;
 215     }
 216   return true;
 217 }
 218
 219 /* Like _Jv_equal, but stop after N characters.  */
 220 jboolean
 221 _Jv_equaln (Utf8Const *a, jstring str, jint n)
 222 {
 223   jint len = str->length();
 224   jint i = 0;
 225   jchar *sptr = _Jv_GetStringChars (str);
 226   unsigned char* ptr = (unsigned char*) a->data;
 227   unsigned char* limit = ptr + a->length;
 228   for (; n-- > 0; i++, sptr++)
 229     {
 230       int ch = UTF8_GET (ptr, limit);
 231       if (i == len)
 232         return ch < 0;
 233       if (ch != *sptr)
 234         return false;
 235     }
 236   return true;
 237 }
 238
 239 /* Count the number of Unicode chars encoded in a given Ut8 string. */
 240 int
 241 _Jv_strLengthUtf8(char* str, int len)
 242 {
 243   unsigned char* ptr;
 244   unsigned char* limit;
 245   int str_length;
 246
 247   ptr = (unsigned char*) str;
 248   limit = ptr + len;
 249   str_length = 0;
 250   for (; ptr < limit; str_length++)
 251     {
 252       if (UTF8_GET (ptr, limit) < 0)
 253         return (-1);
 254     }
 255   return (str_length);
 256 }
 257
 258 /* Calculate a hash value for a string encoded in Utf8 format.
 259  * This returns the same hash value as specified or java.lang.String.hashCode.
 260  */
 261 jint
 262 _Jv_hashUtf8String (char* str, int len)
 263 {
 264   unsigned char* ptr = (unsigned char*) str;
 265   unsigned char* limit = ptr + len;
 266   jint hash = 0;
 267
 268   for (; ptr < limit;)
 269     {
 270       int ch = UTF8_GET (ptr, limit);
 271       /* Updated specification from
 272          http://www.javasoft.com/docs/books/jls/clarify.html. */
 273       hash = (31 * hash) + ch;
 274     }
 275   return hash;
 276 }
 277
 278 void
 279 _Jv_Utf8Const::init(char *s, int len)
 280 {
 281   ::memcpy (data, s, len);
 282   data[len] = 0;
 283   length = len;
 284   hash = _Jv_hashUtf8String (s, len) & 0xFFFF;
 285 }
 286
 287 _Jv_Utf8Const *
 288 _Jv_makeUtf8Const (char* s, int len)
 289 {
 290   if (len < 0)
 291     len = strlen (s);
 292   Utf8Const* m
 293     = (Utf8Const*) _Jv_AllocBytes (_Jv_Utf8Const::space_needed(s, len));
 294   m->init(s, len);
 295   return m;
 296 }
 297
 298 _Jv_Utf8Const *
 299 _Jv_makeUtf8Const (jstring string)
 300 {
 301   jint hash = string->hashCode ();
 302   jint len = _Jv_GetStringUTFLength (string);
 303
 304   Utf8Const* m = (Utf8Const*)
 305     _Jv_AllocBytes (sizeof(Utf8Const) + len + 1);
 306
 307   m->hash = hash;
 308   m->length = len;
 309
 310   _Jv_GetStringUTFRegion (string, 0, string->length (), m->data);
 311   m->data[len] = 0;
 312
 313   return m;
 314 }
 315
 316 \f
 317
 318 #ifdef DEBUG
 319 void
 320 _Jv_Abort (const char *function, const char *file, int line,
 321            const char *message)
 322 #else
 323 void
 324 _Jv_Abort (const char *, const char *, int, const char *message)
 325 #endif
 326 {
 327 #ifdef DEBUG
 328   fprintf (stderr,
 329            "libgcj failure: %s\n   in function %s, file %s, line %d\n",
 330            message, function, file, line);
 331 #else
 332   fprintf (stderr, "libgcj failure: %s\n", message);
 333 #endif
 334   abort ();
 335 }
 336
 337 static void
 338 fail_on_finalization (jobject)
 339 {
 340   JvFail ("object was finalized");
 341 }
 342
 343 void
 344 _Jv_GCWatch (jobject obj)
 345 {
 346   _Jv_RegisterFinalizer (obj, fail_on_finalization);
 347 }
 348
 349 void
 350 _Jv_ThrowBadArrayIndex(jint bad_index)
 351 {
 352   throw new java::lang::ArrayIndexOutOfBoundsException
 353     (java::lang::String::valueOf (bad_index));
 354 }
 355
 356 void
 357 _Jv_ThrowNullPointerException ()
 358 {
 359   throw new java::lang::NullPointerException;
 360 }
 361
 362 // Resolve an entry in the constant pool and return the target
 363 // address.
 364 void *
 365 _Jv_ResolvePoolEntry (jclass this_class, jint index)
 366 {
 367   _Jv_Constants *pool = &this_class->constants;
 368
 369   if ((pool->tags[index] & JV_CONSTANT_ResolvedFlag) != 0)
 370     return pool->data[index].field->u.addr;
 371
 372   JvSynchronize sync (this_class);
 373   return (_Jv_Linker::resolve_pool_entry (this_class, index))
 374     .field->u.addr;
 375 }
 376
 377
 378 // Explicitly throw a no memory exception.
 379 // The collector calls this when it encounters an out-of-memory condition.
 380 void _Jv_ThrowNoMemory()
 381 {
 382   throw no_memory;
 383 }
 384
 385 #ifdef ENABLE_JVMPI
 386 # define JVMPI_NOTIFY_ALLOC(klass,size,obj) \
 387     if (__builtin_expect (_Jv_JVMPI_Notify_OBJECT_ALLOC != 0, false)) \
 388       jvmpi_notify_alloc(klass,size,obj);
 389 static void
 390 jvmpi_notify_alloc(jclass klass, jint size, jobject obj)
 391 {
 392   // Service JVMPI allocation request.
 393   JVMPI_Event event;
 394
 395   event.event_type = JVMPI_EVENT_OBJECT_ALLOC;
 396   event.env_id = NULL;
 397   event.u.obj_alloc.arena_id = 0;
 398   event.u.obj_alloc.class_id = (jobjectID) klass;
 399   event.u.obj_alloc.is_array = 0;
 400   event.u.obj_alloc.size = size;
 401   event.u.obj_alloc.obj_id = (jobjectID) obj;
 402
 403   // FIXME:  This doesn't look right for the Boehm GC.  A GC may
 404   // already be in progress.  _Jv_DisableGC () doesn't wait for it.
 405   // More importantly, I don't see the need for disabling GC, since we
 406   // blatantly have a pointer to obj on our stack, ensuring that the
 407   // object can't be collected.  Even for a nonconservative collector,
 408   // it appears to me that this must be true, since we are about to
 409   // return obj. Isn't this whole approach way too intrusive for
 410   // a useful profiling interface?                      - HB
 411   _Jv_DisableGC ();
 412   (*_Jv_JVMPI_Notify_OBJECT_ALLOC) (&event);
 413   _Jv_EnableGC ();
 414 }
 415 #else /* !ENABLE_JVMPI */
 416 # define JVMPI_NOTIFY_ALLOC(klass,size,obj) /* do nothing */
 417 #endif
 418
 419 // Allocate a new object of class KLASS.
 420 // First a version that assumes that we have no finalizer, and that
 421 // the class is already initialized.
 422 // If we know that JVMPI is disabled, this can be replaced by a direct call
 423 // to the allocator for the appropriate GC.
 424 jobject
 425 _Jv_AllocObjectNoInitNoFinalizer (jclass klass)
 426 {
 427   jint size = klass->size ();
 428   jobject obj = (jobject) _Jv_AllocObj (size, klass);
 429   JVMPI_NOTIFY_ALLOC (klass, size, obj);
 430   return obj;
 431 }
 432
 433 // And now a version that initializes if necessary.
 434 jobject
 435 _Jv_AllocObjectNoFinalizer (jclass klass)
 436 {
 437   _Jv_InitClass (klass);
 438   jint size = klass->size ();
 439   jobject obj = (jobject) _Jv_AllocObj (size, klass);
 440   JVMPI_NOTIFY_ALLOC (klass, size, obj);
 441   return obj;
 442 }
 443
 444 // And now the general version that registers a finalizer if necessary.
 445 jobject
 446 _Jv_AllocObject (jclass klass)
 447 {
 448   jobject obj = _Jv_AllocObjectNoFinalizer (klass);
 449
 450   // We assume that the compiler only generates calls to this routine
 451   // if there really is an interesting finalizer.
 452   // Unfortunately, we still have to the dynamic test, since there may
 453   // be cni calls to this routine.
 454   // Note that on IA64 get_finalizer() returns the starting address of the
 455   // function, not a function pointer.  Thus this still works.
 456   if (klass->vtable->get_finalizer ()
 457       != java::lang::Object::class$.vtable->get_finalizer ())
 458     _Jv_RegisterFinalizer (obj, _Jv_FinalizeObject);
 459   return obj;
 460 }
 461
 462 // Allocate a String, including variable length storage.
 463 jstring
 464 _Jv_AllocString(jsize len)
 465 {
 466   using namespace java::lang;
 467
 468   jsize sz = sizeof(java::lang::String) + len * sizeof(jchar);
 469
 470   // We assert that for strings allocated this way, the data field
 471   // will always point to the object itself.  Thus there is no reason
 472   // for the garbage collector to scan any of it.
 473   // Furthermore, we're about to overwrite the string data, so
 474   // initialization of the object is not an issue.
 475
 476   // String needs no initialization, and there is no finalizer, so
 477   // we can go directly to the collector's allocator interface.
 478   jstring obj = (jstring) _Jv_AllocPtrFreeObj(sz, &String::class$);
 479
 480   obj->data = obj;
 481   obj->boffset = sizeof(java::lang::String);
 482   obj->count = len;
 483   obj->cachedHashCode = 0;
 484
 485   JVMPI_NOTIFY_ALLOC (&String::class$, sz, obj);
 486
 487   return obj;
 488 }
 489
 490 // A version of the above that assumes the object contains no pointers,
 491 // and requires no finalization.  This can't happen if we need pointers
 492 // to locks.
 493 #ifdef JV_HASH_SYNCHRONIZATION
 494 jobject
 495 _Jv_AllocPtrFreeObject (jclass klass)
 496 {
 497   _Jv_InitClass (klass);
 498   jint size = klass->size ();
 499
 500   jobject obj = (jobject) _Jv_AllocPtrFreeObj (size, klass);
 501
 502   JVMPI_NOTIFY_ALLOC (klass, size, obj);
 503
 504   return obj;
 505 }
 506 #endif /* JV_HASH_SYNCHRONIZATION */
 507
 508
 509 // Allocate a new array of Java objects.  Each object is of type
 510 // `elementClass'.  `init' is used to initialize each slot in the
 511 // array.
 512 jobjectArray
 513 _Jv_NewObjectArray (jsize count, jclass elementClass, jobject init)
 514 {
 515   if (__builtin_expect (count < 0, false))
 516     throw new java::lang::NegativeArraySizeException;
 517
 518   JvAssert (! elementClass->isPrimitive ());
 519
 520   // Ensure that elements pointer is properly aligned.
 521   jobjectArray obj = NULL;
 522   size_t size = (size_t) elements (obj);
 523   // Check for overflow.
 524   if (__builtin_expect ((size_t) count >
 525                         (MAX_OBJECT_SIZE - 1 - size) / sizeof (jobject), false))
 526     throw no_memory;
 527
 528   size += count * sizeof (jobject);
 529
 530   jclass klass = _Jv_GetArrayClass (elementClass,
 531                                     elementClass->getClassLoaderInternal());
 532
 533   obj = (jobjectArray) _Jv_AllocArray (size, klass);
 534   // Cast away const.
 535   jsize *lp = const_cast<jsize *> (&obj->length);
 536   *lp = count;
 537   // We know the allocator returns zeroed memory.  So don't bother
 538   // zeroing it again.
 539   if (init)
 540     {
 541       jobject *ptr = elements(obj);
 542       while (--count >= 0)
 543         *ptr++ = init;
 544     }
 545   return obj;
 546 }
 547
 548 // Allocate a new array of primitives.  ELTYPE is the type of the
 549 // element, COUNT is the size of the array.
 550 jobject
 551 _Jv_NewPrimArray (jclass eltype, jint count)
 552 {
 553   int elsize = eltype->size();
 554   if (__builtin_expect (count < 0, false))
 555     throw new java::lang::NegativeArraySizeException;
 556
 557   JvAssert (eltype->isPrimitive ());
 558   jobject dummy = NULL;
 559   size_t size = (size_t) _Jv_GetArrayElementFromElementType (dummy, eltype);
 560
 561   // Check for overflow.
 562   if (__builtin_expect ((size_t) count >
 563                         (MAX_OBJECT_SIZE - size) / elsize, false))
 564     throw no_memory;
 565
 566   jclass klass = _Jv_GetArrayClass (eltype, 0);
 567
 568 # ifdef JV_HASH_SYNCHRONIZATION
 569   // Since the vtable is always statically allocated,
 570   // these are completely pointerfree!  Make sure the GC doesn't touch them.
 571   __JArray *arr =
 572     (__JArray*) _Jv_AllocPtrFreeObj (size + elsize * count, klass);
 573   memset((char *)arr + size, 0, elsize * count);
 574 # else
 575   __JArray *arr = (__JArray*) _Jv_AllocObj (size + elsize * count, klass);
 576   // Note that we assume we are given zeroed memory by the allocator.
 577 # endif
 578   // Cast away const.
 579   jsize *lp = const_cast<jsize *> (&arr->length);
 580   *lp = count;
 581
 582   return arr;
 583 }
 584
 585 jobject
 586 _Jv_NewArray (jint type, jint size)
 587 {
 588   switch (type)
 589     {
 590       case  4:  return JvNewBooleanArray (size);
 591       case  5:  return JvNewCharArray (size);
 592       case  6:  return JvNewFloatArray (size);
 593       case  7:  return JvNewDoubleArray (size);
 594       case  8:  return JvNewByteArray (size);
 595       case  9:  return JvNewShortArray (size);
 596       case 10:  return JvNewIntArray (size);
 597       case 11:  return JvNewLongArray (size);
 598     }
 599   throw new java::lang::InternalError
 600     (JvNewStringLatin1 ("invalid type code in _Jv_NewArray"));
 601 }
 602
 603 // Allocate a possibly multi-dimensional array but don't check that
 604 // any array length is <0.
 605 static jobject
 606 _Jv_NewMultiArrayUnchecked (jclass type, jint dimensions, jint *sizes)
 607 {
 608   JvAssert (type->isArray());
 609   jclass element_type = type->getComponentType();
 610   jobject result;
 611   if (element_type->isPrimitive())
 612     result = _Jv_NewPrimArray (element_type, sizes[0]);
 613   else
 614     result = _Jv_NewObjectArray (sizes[0], element_type, NULL);
 615
 616   if (dimensions > 1)
 617     {
 618       JvAssert (! element_type->isPrimitive());
 619       JvAssert (element_type->isArray());
 620       jobject *contents = elements ((jobjectArray) result);
 621       for (int i = 0; i < sizes[0]; ++i)
 622         contents[i] = _Jv_NewMultiArrayUnchecked (element_type, dimensions - 1,
 623                                                   sizes + 1);
 624     }
 625
 626   return result;
 627 }
 628
 629 jobject
 630 _Jv_NewMultiArray (jclass type, jint dimensions, jint *sizes)
 631 {
 632   for (int i = 0; i < dimensions; ++i)
 633     if (sizes[i] < 0)
 634       throw new java::lang::NegativeArraySizeException;
 635
 636   return _Jv_NewMultiArrayUnchecked (type, dimensions, sizes);
 637 }
 638
 639 jobject
 640 _Jv_NewMultiArray (jclass array_type, jint dimensions, ...)
 641 {
 642   va_list args;
 643   jint sizes[dimensions];
 644   va_start (args, dimensions);
 645   for (int i = 0; i < dimensions; ++i)
 646     {
 647       jint size = va_arg (args, jint);
 648       if (size < 0)
 649         throw new java::lang::NegativeArraySizeException;
 650       sizes[i] = size;
 651     }
 652   va_end (args);
 653
 654   return _Jv_NewMultiArrayUnchecked (array_type, dimensions, sizes);
 655 }
 656
 657 \f
 658
 659 // Ensure 8-byte alignment, for hash synchronization.
 660 #define DECLARE_PRIM_TYPE(NAME)                 \
 661   java::lang::Class _Jv_##NAME##Class __attribute__ ((aligned (8)));
 662
 663 DECLARE_PRIM_TYPE(byte)
 664 DECLARE_PRIM_TYPE(short)
 665 DECLARE_PRIM_TYPE(int)
 666 DECLARE_PRIM_TYPE(long)
 667 DECLARE_PRIM_TYPE(boolean)
 668 DECLARE_PRIM_TYPE(char)
 669 DECLARE_PRIM_TYPE(float)
 670 DECLARE_PRIM_TYPE(double)
 671 DECLARE_PRIM_TYPE(void)
 672
 673 void
 674 _Jv_InitPrimClass (jclass cl, char *cname, char sig, int len)
 675 {
 676   using namespace java::lang::reflect;
 677
 678   // We must set the vtable for the class; the Java constructor
 679   // doesn't do this.
 680   (*(_Jv_VTable **) cl) = java::lang::Class::class$.vtable;
 681
 682   // Initialize the fields we care about.  We do this in the same
 683   // order they are declared in Class.h.
 684   cl->name = _Jv_makeUtf8Const ((char *) cname, -1);
 685   cl->accflags = Modifier::PUBLIC | Modifier::FINAL | Modifier::ABSTRACT;
 686   cl->method_count = sig;
 687   cl->size_in_bytes = len;
 688   cl->vtable = JV_PRIMITIVE_VTABLE;
 689   cl->state = JV_STATE_DONE;
 690   cl->depth = -1;
 691 }
 692
 693 jclass
 694 _Jv_FindClassFromSignature (char *sig, java::lang::ClassLoader *loader,
 695                             char **endp)
 696 {
 697   // First count arrays.
 698   int array_count = 0;
 699   while (*sig == '[')
 700     {
 701       ++sig;
 702       ++array_count;
 703     }
 704
 705   jclass result = NULL;
 706   switch (*sig)
 707     {
 708     case 'B':
 709       result = JvPrimClass (byte);
 710       break;
 711     case 'S':
 712       result = JvPrimClass (short);
 713       break;
 714     case 'I':
 715       result = JvPrimClass (int);
 716       break;
 717     case 'J':
 718       result = JvPrimClass (long);
 719       break;
 720     case 'Z':
 721       result = JvPrimClass (boolean);
 722       break;
 723     case 'C':
 724       result = JvPrimClass (char);
 725       break;
 726     case 'F':
 727       result = JvPrimClass (float);
 728       break;
 729     case 'D':
 730       result = JvPrimClass (double);
 731       break;
 732     case 'V':
 733       result = JvPrimClass (void);
 734       break;
 735     case 'L':
 736       {
 737         char *save = ++sig;
 738         while (*sig && *sig != ';')
 739           ++sig;
 740         // Do nothing if signature appears to be malformed.
 741         if (*sig == ';')
 742           {
 743             _Jv_Utf8Const *name = _Jv_makeUtf8Const (save, sig - save);
 744             result = _Jv_FindClass (name, loader);
 745           }
 746         break;
 747       }
 748     default:
 749       // Do nothing -- bad signature.
 750       break;
 751     }
 752
 753   if (endp)
 754     {
 755       // Not really the "end", but the last valid character that we
 756       // looked at.
 757       *endp = sig;
 758     }
 759
 760   if (! result)
 761     return NULL;
 762
 763   // Find arrays.
 764   while (array_count-- > 0)
 765     result = _Jv_GetArrayClass (result, loader);
 766   return result;
 767 }
 768
 769 \f
 770
 771 JArray<jstring> *
 772 JvConvertArgv (int argc, const char **argv)
 773 {
 774   if (argc < 0)
 775     argc = 0;
 776   jobjectArray ar = JvNewObjectArray(argc, &java::lang::String::class$, NULL);
 777   jobject *ptr = elements(ar);
 778   jbyteArray bytes = NULL;
 779   for (int i = 0;  i < argc;  i++)
 780     {
 781       const char *arg = argv[i];
 782       int len = strlen (arg);
 783       if (bytes == NULL || bytes->length < len)
 784         bytes = JvNewByteArray (len);
 785       jbyte *bytePtr = elements (bytes);
 786       // We assume jbyte == char.
 787       memcpy (bytePtr, arg, len);
 788
 789       // Now convert using the default encoding.
 790       *ptr++ = new java::lang::String (bytes, 0, len);
 791     }
 792   return (JArray<jstring>*) ar;
 793 }
 794
 795 // FIXME: These variables are static so that they will be
 796 // automatically scanned by the Boehm collector.  This is needed
 797 // because with qthreads the collector won't scan the initial stack --
 798 // it will only scan the qthreads stacks.
 799
 800 // Command line arguments.
 801 static JArray<jstring> *arg_vec;
 802
 803 // The primary thread.
 804 static java::lang::Thread *main_thread;
 805
 806 #ifndef DISABLE_GETENV_PROPERTIES
 807
 808 static char *
 809 next_property_key (char *s, size_t *length)
 810 {
 811   size_t l = 0;
 812
 813   JvAssert (s);
 814
 815   // Skip over whitespace
 816   while (isspace (*s))
 817     s++;
 818
 819   // If we've reached the end, return NULL.  Also return NULL if for
 820   // some reason we've come across a malformed property string.
 821   if (*s == 0
 822       || *s == ':'
 823       || *s == '=')
 824     return NULL;
 825
 826   // Determine the length of the property key.
 827   while (s[l] != 0
 828          && ! isspace (s[l])
 829          && s[l] != ':'
 830          && s[l] != '=')
 831     {
 832       if (s[l] == '\\'
 833           && s[l+1] != 0)
 834         l++;
 835       l++;
 836     }
 837
 838   *length = l;
 839
 840   return s;
 841 }
 842
 843 static char *
 844 next_property_value (char *s, size_t *length)
 845 {
 846   size_t l = 0;
 847
 848   JvAssert (s);
 849
 850   while (isspace (*s))
 851     s++;
 852
 853   if (*s == ':'
 854       || *s == '=')
 855     s++;
 856
 857   while (isspace (*s))
 858     s++;
 859
 860   // If we've reached the end, return NULL.
 861   if (*s == 0)
 862     return NULL;
 863
 864   // Determine the length of the property value.
 865   while (s[l] != 0
 866          && ! isspace (s[l])
 867          && s[l] != ':'
 868          && s[l] != '=')
 869     {
 870       if (s[l] == '\\'
 871           && s[l+1] != 0)
 872         l += 2;
 873       else
 874         l++;
 875     }
 876
 877   *length = l;
 878
 879   return s;
 880 }
 881
 882 static void
 883 process_gcj_properties ()
 884 {
 885   char *props = getenv("GCJ_PROPERTIES");
 886   char *p = props;
 887   size_t length;
 888   size_t property_count = 0;
 889
 890   if (NULL == props)
 891     return;
 892
 893   // Whip through props quickly in order to count the number of
 894   // property values.
 895   while (p && (p = next_property_key (p, &length)))
 896     {
 897       // Skip to the end of the key
 898       p += length;
 899
 900       p = next_property_value (p, &length);
 901       if (p)
 902         p += length;
 903
 904       property_count++;
 905     }
 906
 907   // Allocate an array of property value/key pairs.
 908   _Jv_Environment_Properties =
 909     (property_pair *) malloc (sizeof(property_pair)
 910                               * (property_count + 1));
 911
 912   // Go through the properties again, initializing _Jv_Properties
 913   // along the way.
 914   p = props;
 915   property_count = 0;
 916   while (p && (p = next_property_key (p, &length)))
 917     {
 918       _Jv_Environment_Properties[property_count].key = p;
 919       _Jv_Environment_Properties[property_count].key_length = length;
 920
 921       // Skip to the end of the key
 922       p += length;
 923
 924       p = next_property_value (p, &length);
 925
 926       _Jv_Environment_Properties[property_count].value = p;
 927       _Jv_Environment_Properties[property_count].value_length = length;
 928
 929       if (p)
 930         p += length;
 931
 932       property_count++;
 933     }
 934   memset ((void *) &_Jv_Environment_Properties[property_count],
 935           0, sizeof (property_pair));
 936
 937   // Null terminate the strings.
 938   for (property_pair *prop = &_Jv_Environment_Properties[0];
 939        prop->key != NULL;
 940        prop++)
 941     {
 942       prop->key[prop->key_length] = 0;
 943       prop->value[prop->value_length] = 0;
 944     }
 945 }
 946 #endif // DISABLE_GETENV_PROPERTIES
 947
 948 namespace gcj
 949 {
 950   _Jv_Utf8Const *void_signature;
 951   _Jv_Utf8Const *clinit_name;
 952   _Jv_Utf8Const *init_name;
 953   _Jv_Utf8Const *finit_name;
 954
 955   bool runtimeInitialized = false;
 956
 957   // When true, print debugging information about class loading.
 958   bool verbose_class_flag;
 959
 960   // When true, enable the bytecode verifier and BC-ABI type verification.
 961   bool verifyClasses = true;
 962 }
 963
 964 // We accept all non-standard options accepted by Sun's java command,
 965 // for compatibility with existing application launch scripts.
 966 static jint
 967 parse_x_arg (char* option_string)
 968 {
 969   if (strlen (option_string) <= 0)
 970     return -1;
 971
 972   if (! strcmp (option_string, "int"))
 973     {
 974       // FIXME: this should cause the vm to never load shared objects
 975     }
 976   else if (! strcmp (option_string, "mixed"))
 977     {
 978       // FIXME: allow interpreted and native code
 979     }
 980   else if (! strcmp (option_string, "batch"))
 981     {
 982       // FIXME: disable background JIT'ing
 983     }
 984   else if (! strcmp (option_string, "debug"))
 985     {
 986       // FIXME: add JDWP/JVMDI support
 987     }
 988   else if (! strncmp (option_string, "bootclasspath:", 14))
 989     {
 990       // FIXME: add a parse_bootclasspath_arg function
 991     }
 992   else if (! strncmp (option_string, "bootclasspath/a:", 16))
 993     {
 994     }
 995   else if (! strncmp (option_string, "bootclasspath/p:", 16))
 996     {
 997     }
 998   else if (! strcmp (option_string, "check:jni"))
 999     {
1000       // FIXME: enable strict JNI checking
1001     }
1002   else if (! strcmp (option_string, "future"))
1003     {
1004       // FIXME: enable strict class file format checks
1005     }
1006   else if (! strcmp (option_string, "noclassgc"))
1007     {
1008       // FIXME: disable garbage collection for classes
1009     }
1010   else if (! strcmp (option_string, "incgc"))
1011     {
1012       // FIXME: incremental garbage collection
1013     }
1014   else if (! strncmp (option_string, "loggc:", 6))
1015     {
1016       if (option_string[6] == '\0')
1017         {
1018           fprintf (stderr,
1019                    "libgcj: filename argument expected for loggc option\n");
1020           return -1;
1021         }
1022       // FIXME: set gc logging filename
1023     }
1024   else if (! strncmp (option_string, "ms", 2))
1025     {
1026       // FIXME: ignore this option until PR 20699 is fixed.
1027       // _Jv_SetInitialHeapSize (option_string + 2);
1028     }
1029   else if (! strncmp (option_string, "mx", 2))
1030     _Jv_SetMaximumHeapSize (option_string + 2);
1031   else if (! strcmp (option_string, "prof"))
1032     {
1033       // FIXME: enable profiling of program running in vm
1034     }
1035   else if (! strncmp (option_string, "runhprof:", 9))
1036     {
1037       // FIXME: enable specific type of vm profiling.  add a
1038       // parse_runhprof_arg function
1039     }
1040   else if (! strcmp (option_string, "rs"))
1041     {
1042       // FIXME: reduced system signal usage.  disable thread dumps,
1043       // only terminate in response to user-initiated calls,
1044       // e.g. System.exit()
1045     }
1046   else if (! strncmp (option_string, "ss", 2))
1047     {
1048       // FIXME: set thread stack size
1049     }
1050   else if (! strcmp (option_string, "X:+UseAltSigs"))
1051     {
1052       // FIXME: use signals other than SIGUSR1 and SIGUSR2
1053     }
1054   else if (! strcmp (option_string, "share:off"))
1055     {
1056       // FIXME: don't share class data
1057     }
1058   else if (! strcmp (option_string, "share:auto"))
1059     {
1060       // FIXME: share class data where possible
1061     }
1062   else if (! strcmp (option_string, "share:on"))
1063     {
1064       // FIXME: fail if impossible to share class data
1065     }
1066
1067   return 0;
1068 }
1069
1070 static jint
1071 parse_verbose_args (char* option_string,
1072                     bool ignore_unrecognized)
1073 {
1074   size_t len = sizeof ("-verbose") - 1;
1075
1076   if (strlen (option_string) < len)
1077     return -1;
1078
1079   if (option_string[len] == ':'
1080       && option_string[len + 1] != '\0')
1081     {
1082       char* verbose_args = option_string + len + 1;
1083
1084       do
1085         {
1086           if (! strncmp (verbose_args,
1087                          "gc", sizeof ("gc") - 1))
1088             {
1089               if (verbose_args[sizeof ("gc") - 1] == '\0'
1090                   || verbose_args[sizeof ("gc") - 1] == ',')
1091                 {
1092                   // FIXME: we should add functions to boehm-gc that
1093                   // toggle GC_print_stats, GC_PRINT_ADDRESS_MAP and
1094                   // GC_print_back_height.
1095                   verbose_args += sizeof ("gc") - 1;
1096                 }
1097               else
1098                 {
1099                 verbose_arg_err:
1100                   fprintf (stderr, "libgcj: unknown verbose option: %s\n",
1101                            option_string);
1102                   return -1;
1103                 }
1104             }
1105           else if (! strncmp (verbose_args,
1106                               "class",
1107                               sizeof ("class") - 1))
1108             {
1109               if (verbose_args[sizeof ("class") - 1] == '\0'
1110                   || verbose_args[sizeof ("class") - 1] == ',')
1111                 {
1112                   gcj::verbose_class_flag = true;
1113                   verbose_args += sizeof ("class") - 1;
1114                 }
1115               else
1116                 goto verbose_arg_err;
1117             }
1118           else if (! strncmp (verbose_args, "jni",
1119                               sizeof ("jni") - 1))
1120             {
1121               if (verbose_args[sizeof ("jni") - 1] == '\0'
1122                   || verbose_args[sizeof ("jni") - 1] == ',')
1123                 {
1124                   // FIXME: enable JNI messages.
1125                   verbose_args += sizeof ("jni") - 1;
1126                 }
1127               else
1128                 goto verbose_arg_err;
1129             }
1130           else if (ignore_unrecognized
1131                    && verbose_args[0] == 'X')
1132             {
1133               // ignore unrecognized non-standard verbose option
1134               while (verbose_args[0] != '\0'
1135                      && verbose_args[0] != ',')
1136                 verbose_args++;
1137             }
1138           else if (verbose_args[0] == ',')
1139             {
1140               verbose_args++;
1141             }
1142           else
1143             goto verbose_arg_err;
1144
1145           if (verbose_args[0] == ',')
1146             verbose_args++;
1147         }
1148       while (verbose_args[0] != '\0');
1149     }
1150   else if (option_string[len] == 'g'
1151            && option_string[len + 1] == 'c'
1152            && option_string[len + 2] == '\0')
1153     {
1154       // FIXME: we should add functions to boehm-gc that
1155       // toggle GC_print_stats, GC_PRINT_ADDRESS_MAP and
1156       // GC_print_back_height.
1157       return 0;
1158     }
1159   else if (option_string[len] == '\0')
1160     {
1161       gcj::verbose_class_flag = true;
1162       return 0;
1163     }
1164   else
1165     {
1166       // unrecognized option beginning with -verbose
1167       return -1;
1168     }
1169   return 0;
1170 }
1171
1172 static jint
1173 parse_init_args (JvVMInitArgs* vm_args)
1174 {
1175   // if _Jv_Compiler_Properties is non-NULL then it needs to be
1176   // re-allocated dynamically.
1177   if (_Jv_Compiler_Properties)
1178     {
1179       const char** props = _Jv_Compiler_Properties;
1180       _Jv_Compiler_Properties = NULL;
1181
1182       for (int i = 0; props[i]; i++)
1183         {
1184           _Jv_Compiler_Properties = (const char**) _Jv_Realloc
1185             (_Jv_Compiler_Properties,
1186              (_Jv_Properties_Count + 1) * sizeof (const char*));
1187           _Jv_Compiler_Properties[_Jv_Properties_Count++] = props[i];
1188         }
1189     }
1190
1191   if (vm_args == NULL)
1192     return 0;
1193
1194   for (int i = 0; i < vm_args->nOptions; ++i)
1195     {
1196       char* option_string = vm_args->options[i].optionString;
1197       if (! strcmp (option_string, "vfprintf")
1198           || ! strcmp (option_string, "exit")
1199           || ! strcmp (option_string, "abort"))
1200         {
1201           // FIXME: we are required to recognize these, but for
1202           // now we don't handle them in any way.
1203           continue;
1204         }
1205       else if (! strncmp (option_string,
1206                           "-verbose", sizeof ("-verbose") - 1))
1207         {
1208           jint result = parse_verbose_args (option_string,
1209                                             vm_args->ignoreUnrecognized);
1210           if (result < 0)
1211             return result;
1212         }
1213       else if (! strncmp (option_string, "-D", 2))
1214         {
1215           _Jv_Compiler_Properties = (const char**) _Jv_Realloc
1216             (_Jv_Compiler_Properties,
1217              (_Jv_Properties_Count + 1) * sizeof (char*));
1218
1219           _Jv_Compiler_Properties[_Jv_Properties_Count++] =
1220             strdup (option_string + 2);
1221
1222           continue;
1223         }
1224       else if (vm_args->ignoreUnrecognized)
1225         {
1226           if (option_string[0] == '_')
1227             parse_x_arg (option_string + 1);
1228           else if (! strncmp (option_string, "-X", 2))
1229             parse_x_arg (option_string + 2);
1230           else
1231             {
1232             unknown_option:
1233               fprintf (stderr, "libgcj: unknown option: %s\n", option_string);
1234               return -1;
1235             }
1236         }
1237       else
1238         goto unknown_option;
1239     }
1240   return 0;
1241 }
1242
1243 jint
1244 _Jv_CreateJavaVM (JvVMInitArgs* vm_args)
1245 {
1246   using namespace gcj;
1247
1248   if (runtimeInitialized)
1249     return -1;
1250
1251   runtimeInitialized = true;
1252
1253   jint result = parse_init_args (vm_args);
1254   if (result < 0)
1255     return -1;
1256
1257   PROCESS_GCJ_PROPERTIES;
1258
1259   /* Threads must be initialized before the GC, so that it inherits the
1260      signal mask.  */
1261   _Jv_InitThreads ();
1262   _Jv_InitGC ();
1263   _Jv_InitializeSyncMutex ();
1264
1265 #ifdef INTERPRETER
1266   _Jv_InitInterpreter ();
1267 #endif
1268
1269 #ifdef HANDLE_SEGV
1270   INIT_SEGV;
1271 #endif
1272
1273 #ifdef HANDLE_FPE
1274   INIT_FPE;
1275 #endif
1276
1277   /* Initialize Utf8 constants declared in jvm.h. */
1278   void_signature = _Jv_makeUtf8Const ("()V", 3);
1279   clinit_name = _Jv_makeUtf8Const ("<clinit>", 8);
1280   init_name = _Jv_makeUtf8Const ("<init>", 6);
1281   finit_name = _Jv_makeUtf8Const ("finit$", 6);
1282
1283   /* Initialize built-in classes to represent primitive TYPEs. */
1284   _Jv_InitPrimClass (&_Jv_byteClass,    "byte",    'B', 1);
1285   _Jv_InitPrimClass (&_Jv_shortClass,   "short",   'S', 2);
1286   _Jv_InitPrimClass (&_Jv_intClass,     "int",     'I', 4);
1287   _Jv_InitPrimClass (&_Jv_longClass,    "long",    'J', 8);
1288   _Jv_InitPrimClass (&_Jv_booleanClass, "boolean", 'Z', 1);
1289   _Jv_InitPrimClass (&_Jv_charClass,    "char",    'C', 2);
1290   _Jv_InitPrimClass (&_Jv_floatClass,   "float",   'F', 4);
1291   _Jv_InitPrimClass (&_Jv_doubleClass,  "double",  'D', 8);
1292   _Jv_InitPrimClass (&_Jv_voidClass,    "void",    'V', 0);
1293
1294   // Turn stack trace generation off while creating exception objects.
1295   _Jv_InitClass (&java::lang::VMThrowable::class$);
1296   java::lang::VMThrowable::trace_enabled = 0;
1297
1298   // We have to initialize this fairly early, to avoid circular class
1299   // initialization.  In particular we want to start the
1300   // initialization of ClassLoader before we start the initialization
1301   // of VMClassLoader.
1302   _Jv_InitClass (&java::lang::ClassLoader::class$);
1303
1304   // Set up the system class loader and the bootstrap class loader.
1305   gnu::gcj::runtime::ExtensionClassLoader::initialize();
1306   java::lang::VMClassLoader::initialize(JvNewStringLatin1(TOOLEXECLIBDIR));
1307
1308   _Jv_RegisterBootstrapPackages();
1309
1310   no_memory = new java::lang::OutOfMemoryError;
1311
1312   java::lang::VMThrowable::trace_enabled = 1;
1313
1314 #ifdef USE_LTDL
1315   LTDL_SET_PRELOADED_SYMBOLS ();
1316 #endif
1317
1318   _Jv_platform_initialize ();
1319
1320   _Jv_JNI_Init ();
1321
1322   _Jv_GCInitializeFinalizers (&::gnu::gcj::runtime::FinalizerThread::finalizerReady);
1323
1324   // Start the GC finalizer thread.  A VirtualMachineError can be
1325   // thrown by the runtime if, say, threads aren't available.
1326   try
1327     {
1328       using namespace gnu::gcj::runtime;
1329       FinalizerThread *ft = new FinalizerThread ();
1330       ft->start ();
1331     }
1332   catch (java::lang::VirtualMachineError *ignore)
1333     {
1334     }
1335
1336   return 0;
1337 }
1338
1339 void
1340 _Jv_RunMain (JvVMInitArgs *vm_args, jclass klass, const char *name, int argc,
1341              const char **argv, bool is_jar)
1342 {
1343 #ifndef DISABLE_MAIN_ARGS
1344   _Jv_SetArgs (argc, argv);
1345 #endif
1346
1347   java::lang::Runtime *runtime = NULL;
1348
1349   try
1350     {
1351       if (_Jv_CreateJavaVM (vm_args) < 0)
1352         {
1353           fprintf (stderr, "libgcj: couldn't create virtual machine\n");
1354           exit (1);
1355         }
1356
1357       // Get the Runtime here.  We want to initialize it before searching
1358       // for `main'; that way it will be set up if `main' is a JNI method.
1359       runtime = java::lang::Runtime::getRuntime ();
1360
1361 #ifdef DISABLE_MAIN_ARGS
1362       arg_vec = JvConvertArgv (0, 0);
1363 #else
1364       arg_vec = JvConvertArgv (argc - 1, argv + 1);
1365 #endif
1366
1367       using namespace gnu::java::lang;
1368       if (klass)
1369         main_thread = new MainThread (klass, arg_vec);
1370       else
1371         main_thread = new MainThread (JvNewStringLatin1 (name),
1372                                       arg_vec, is_jar);
1373     }
1374   catch (java::lang::Throwable *t)
1375     {
1376       java::lang::System::err->println (JvNewStringLatin1
1377         ("Exception during runtime initialization"));
1378       t->printStackTrace();
1379       if (runtime)
1380         runtime->exit (1);
1381       // In case the runtime creation failed.
1382       ::exit (1);
1383     }
1384
1385   _Jv_AttachCurrentThread (main_thread);
1386   _Jv_ThreadRun (main_thread);
1387   _Jv_ThreadWait ();
1388
1389   int status = (int) java::lang::ThreadGroup::had_uncaught_exception;
1390   runtime->exit (status);
1391 }
1392
1393 void
1394 _Jv_RunMain (jclass klass, const char *name, int argc, const char **argv,
1395              bool is_jar)
1396 {
1397   _Jv_RunMain (NULL, klass, name, argc, argv, is_jar);
1398 }
1399
1400 void
1401 JvRunMain (jclass klass, int argc, const char **argv)
1402 {
1403   _Jv_RunMain (klass, NULL, argc, argv, false);
1404 }
1405
1406 \f
1407
1408 // Parse a string and return a heap size.
1409 static size_t
1410 parse_heap_size (const char *spec)
1411 {
1412   char *end;
1413   unsigned long val = strtoul (spec, &end, 10);
1414   if (*end == 'k' || *end == 'K')
1415     val *= 1024;
1416   else if (*end == 'm' || *end == 'M')
1417     val *= 1048576;
1418   return (size_t) val;
1419 }
1420
1421 // Set the initial heap size.  This might be ignored by the GC layer.
1422 // This must be called before _Jv_RunMain.
1423 void
1424 _Jv_SetInitialHeapSize (const char *arg)
1425 {
1426   size_t size = parse_heap_size (arg);
1427   _Jv_GCSetInitialHeapSize (size);
1428 }
1429
1430 // Set the maximum heap size.  This might be ignored by the GC layer.
1431 // This must be called before _Jv_RunMain.
1432 void
1433 _Jv_SetMaximumHeapSize (const char *arg)
1434 {
1435   size_t size = parse_heap_size (arg);
1436   _Jv_GCSetMaximumHeapSize (size);
1437 }
1438
1439 \f
1440
1441 void *
1442 _Jv_Malloc (jsize size)
1443 {
1444   if (__builtin_expect (size == 0, false))
1445     size = 1;
1446   void *ptr = malloc ((size_t) size);
1447   if (__builtin_expect (ptr == NULL, false))
1448     throw no_memory;
1449   return ptr;
1450 }
1451
1452 void *
1453 _Jv_Realloc (void *ptr, jsize size)
1454 {
1455   if (__builtin_expect (size == 0, false))
1456     size = 1;
1457   ptr = realloc (ptr, (size_t) size);
1458   if (__builtin_expect (ptr == NULL, false))
1459     throw no_memory;
1460   return ptr;
1461 }
1462
1463 void *
1464 _Jv_MallocUnchecked (jsize size)
1465 {
1466   if (__builtin_expect (size == 0, false))
1467     size = 1;
1468   return malloc ((size_t) size);
1469 }
1470
1471 void
1472 _Jv_Free (void* ptr)
1473 {
1474   return free (ptr);
1475 }
1476
1477 \f
1478
1479 // In theory, these routines can be #ifdef'd away on machines which
1480 // support divide overflow signals.  However, we never know if some
1481 // code might have been compiled with "-fuse-divide-subroutine", so we
1482 // always include them in libgcj.
1483
1484 jint
1485 _Jv_divI (jint dividend, jint divisor)
1486 {
1487   if (__builtin_expect (divisor == 0, false))
1488     {
1489       java::lang::ArithmeticException *arithexception
1490         = new java::lang::ArithmeticException (JvNewStringLatin1 ("/ by zero"));
1491       throw arithexception;
1492     }
1493
1494   if (dividend == (jint) 0x80000000L && divisor == -1)
1495     return dividend;
1496
1497   return dividend / divisor;
1498 }
1499
1500 jint
1501 _Jv_remI (jint dividend, jint divisor)
1502 {
1503   if (__builtin_expect (divisor == 0, false))
1504     {
1505       java::lang::ArithmeticException *arithexception
1506         = new java::lang::ArithmeticException (JvNewStringLatin1 ("/ by zero"));
1507       throw arithexception;
1508     }
1509
1510   if (dividend == (jint) 0x80000000L && divisor == -1)
1511     return 0;
1512
1513   return dividend % divisor;
1514 }
1515
1516 jlong
1517 _Jv_divJ (jlong dividend, jlong divisor)
1518 {
1519   if (__builtin_expect (divisor == 0, false))
1520     {
1521       java::lang::ArithmeticException *arithexception
1522         = new java::lang::ArithmeticException (JvNewStringLatin1 ("/ by zero"));
1523       throw arithexception;
1524     }
1525
1526   if (dividend == (jlong) 0x8000000000000000LL && divisor == -1)
1527     return dividend;
1528
1529   return dividend / divisor;
1530 }
1531
1532 jlong
1533 _Jv_remJ (jlong dividend, jlong divisor)
1534 {
1535   if (__builtin_expect (divisor == 0, false))
1536     {
1537       java::lang::ArithmeticException *arithexception
1538         = new java::lang::ArithmeticException (JvNewStringLatin1 ("/ by zero"));
1539       throw arithexception;
1540     }
1541
1542   if (dividend == (jlong) 0x8000000000000000LL && divisor == -1)
1543     return 0;
1544
1545   return dividend % divisor;
1546 }
1547
1548 \f
1549
1550 // Return true if SELF_KLASS can access a field or method in
1551 // OTHER_KLASS.  The field or method's access flags are specified in
1552 // FLAGS.
1553 jboolean
1554 _Jv_CheckAccess (jclass self_klass, jclass other_klass, jint flags)
1555 {
1556   using namespace java::lang::reflect;
1557   return ((self_klass == other_klass)
1558           || ((flags & Modifier::PUBLIC) != 0)
1559           || (((flags & Modifier::PROTECTED) != 0)
1560               && _Jv_IsAssignableFromSlow (other_klass, self_klass))
1561           || (((flags & Modifier::PRIVATE) == 0)
1562               && _Jv_ClassNameSamePackage (self_klass->name,
1563                                            other_klass->name)));
1564 }