libjava/prims.cc

   1 // prims.cc - Code for core of runtime environment.
   2
   3 /* Copyright (C) 1998, 1999  Cygnus Solutions
   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
  13 #include <stdlib.h>
  14 #include <stdarg.h>
  15 #include <stdio.h>
  16 #include <string.h>
  17 #include <signal.h>
  18
  19 #pragma implementation "gcj/array.h"
  20
  21 #include <gcj/cni.h>
  22 #include <jvm.h>
  23 #include <java-signal.h>
  24 #include <java-threads.h>
  25
  26 #include <java/lang/Class.h>
  27 #include <java/lang/Runtime.h>
  28 #include <java/lang/String.h>
  29 #include <java/lang/Thread.h>
  30 #include <java/lang/ThreadGroup.h>
  31 #include <java/lang/FirstThread.h>
  32 #include <java/lang/ArrayIndexOutOfBoundsException.h>
  33 #include <java/lang/ArithmeticException.h>
  34 #include <java/lang/ClassFormatError.h>
  35 #include <java/lang/ClassCastException.h>
  36 #include <java/lang/NegativeArraySizeException.h>
  37 #include <java/lang/NullPointerException.h>
  38 #include <java/lang/OutOfMemoryError.h>
  39 #include <java/lang/ArrayStoreException.h>
  40 #include <java/lang/System.h>
  41 #include <java/lang/reflect/Modifier.h>
  42 #include <java/io/PrintStream.h>
  43
  44 #ifdef USE_LTDL
  45 #include <ltdl.h>
  46 #endif
  47
  48 #define ObjectClass _CL_Q34java4lang6Object
  49 extern java::lang::Class ObjectClass;
  50
  51 // We allocate a single OutOfMemoryError exception which we keep
  52 // around for use if we run out of memory.
  53 static java::lang::OutOfMemoryError *no_memory;
  54
  55 // Largest representable size_t.
  56 #define SIZE_T_MAX ((size_t) (~ (size_t) 0))
  57
  58 \f
  59
  60 #ifdef HANDLE_SEGV
  61 static java::lang::NullPointerException *nullp;
  62 SIGNAL_HANDLER (catch_segv)
  63 {
  64   MAKE_THROW_FRAME;
  65   _Jv_Throw (nullp);
  66 }
  67 #endif
  68
  69 static java::lang::ArithmeticException *arithexception;
  70
  71 #ifdef HANDLE_FPE
  72 SIGNAL_HANDLER (catch_fpe)
  73 {
  74 #ifdef HANDLE_DIVIDE_OVERFLOW
  75   HANDLE_DIVIDE_OVERFLOW;
  76 #else
  77   MAKE_THROW_FRAME;
  78 #endif
  79   _Jv_Throw (arithexception);
  80 }
  81 #endif
  82
  83 \f
  84
  85 jboolean
  86 _Jv_equalUtf8Consts (Utf8Const* a, Utf8Const *b)
  87 {
  88   register int len;
  89   register _Jv_ushort *aptr, *bptr;
  90   if (a == b)
  91     return true;
  92   if (a->hash != b->hash)
  93     return false;
  94   len = a->length;
  95   if (b->length != len)
  96     return false;
  97   aptr = (_Jv_ushort *)a->data;
  98   bptr = (_Jv_ushort *)b->data;
  99   len = (len + 1) >> 1;
 100   while (--len >= 0)
 101     if (*aptr++ != *bptr++)
 102       return false;
 103   return true;
 104 }
 105
 106 /* True iff A is equal to STR.
 107    HASH is STR->hashCode().
 108 */
 109
 110 jboolean
 111 _Jv_equal (Utf8Const* a, jstring str, jint hash)
 112 {
 113   if (a->hash != (_Jv_ushort) hash)
 114     return false;
 115   jint len = str->length();
 116   jint i = 0;
 117   jchar *sptr = _Jv_GetStringChars (str);
 118   register unsigned char* ptr = (unsigned char*) a->data;
 119   register unsigned char* limit = ptr + a->length;
 120   for (;; i++, sptr++)
 121     {
 122       int ch = UTF8_GET (ptr, limit);
 123       if (i == len)
 124         return ch < 0;
 125       if (ch != *sptr)
 126         return false;
 127     }
 128   return true;
 129 }
 130
 131 /* Count the number of Unicode chars encoded in a given Ut8 string. */
 132 int
 133 _Jv_strLengthUtf8(char* str, int len)
 134 {
 135   register unsigned char* ptr;
 136   register unsigned char* limit;
 137   int str_length;
 138
 139   ptr = (unsigned char*) str;
 140   limit = ptr + len;
 141   str_length = 0;
 142   for (; ptr < limit; str_length++) {
 143     if (UTF8_GET (ptr, limit) < 0) {
 144       return (-1);
 145     }
 146   }
 147   return (str_length);
 148 }
 149
 150 /* Calculate a hash value for a string encoded in Utf8 format.
 151  * This returns the same hash value as specified or java.lang.String.hashCode.
 152  */
 153 static jint
 154 hashUtf8String (char* str, int len)
 155 {
 156   register unsigned char* ptr = (unsigned char*) str;
 157   register unsigned char* limit = ptr + len;
 158   jint hash = 0;
 159
 160   for (; ptr < limit;)
 161     {
 162       int ch = UTF8_GET (ptr, limit);
 163       /* Updated specification from
 164          http://www.javasoft.com/docs/books/jls/clarify.html. */
 165       hash = (31 * hash) + ch;
 166     }
 167   return hash;
 168 }
 169
 170 _Jv_Utf8Const *
 171 _Jv_makeUtf8Const (char* s, int len)
 172 {
 173   if (len < 0)
 174     len = strlen (s);
 175   Utf8Const* m = (Utf8Const*) _Jv_AllocBytes (sizeof(Utf8Const) + len + 1);
 176   if (! m)
 177     JvThrow (no_memory);
 178   memcpy (m->data, s, len);
 179   m->data[len] = 0;
 180   m->length = len;
 181   m->hash = hashUtf8String (s, len) & 0xFFFF;
 182   return (m);
 183 }
 184
 185 _Jv_Utf8Const *
 186 _Jv_makeUtf8Const (jstring string)
 187 {
 188   jint hash = string->hashCode ();
 189   jint len = _Jv_GetStringUTFLength (string);
 190
 191   Utf8Const* m = (Utf8Const*)
 192     _Jv_AllocBytesChecked (sizeof(Utf8Const) + len + 1);
 193
 194   m->hash = hash;
 195   m->length = len;
 196
 197   _Jv_GetStringUTFRegion (string, 0, string->length (), m->data);
 198   m->data[len] = 0;
 199
 200   return m;
 201 }
 202
 203 \f
 204
 205 #ifdef DEBUG
 206 void
 207 _Jv_Abort (const char *function, const char *file, int line,
 208            const char *message)
 209 #else
 210 void
 211 _Jv_Abort (const char *, const char *, int, const char *message)
 212 #endif
 213 {
 214 #ifdef DEBUG
 215   fprintf (stderr,
 216            "libgcj failure: %s\n   in function %s, file %s, line %d\n",
 217            message, function, file, line);
 218 #else
 219   java::io::PrintStream *err = java::lang::System::err;
 220   err->print(JvNewStringLatin1 ("libgcj failure: "));
 221   err->println(JvNewStringLatin1 (message));
 222   err->flush();
 223 #endif
 224   abort ();
 225 }
 226
 227 static void
 228 fail_on_finalization (jobject)
 229 {
 230   JvFail ("object was finalized");
 231 }
 232
 233 void
 234 _Jv_GCWatch (jobject obj)
 235 {
 236   _Jv_RegisterFinalizer (obj, fail_on_finalization);
 237 }
 238
 239 void
 240 _Jv_ThrowBadArrayIndex(jint bad_index)
 241 {
 242   JvThrow (new java::lang::ArrayIndexOutOfBoundsException
 243            (java::lang::String::valueOf(bad_index)));
 244 }
 245
 246 void*
 247 _Jv_CheckCast (jclass c, jobject obj)
 248 {
 249   if (obj != NULL && ! c->isAssignableFrom(obj->getClass()))
 250     JvThrow (new java::lang::ClassCastException);
 251   return obj;
 252 }
 253
 254 void
 255 _Jv_CheckArrayStore (jobject arr, jobject obj)
 256 {
 257   if (obj)
 258     {
 259       JvAssert (arr != NULL);
 260       jclass arr_class = arr->getClass();
 261       JvAssert (arr_class->isArray());
 262       jclass elt_class = arr_class->getComponentType();
 263       jclass obj_class = obj->getClass();
 264       if (! elt_class->isAssignableFrom(obj_class))
 265         JvThrow (new java::lang::ArrayStoreException);
 266     }
 267 }
 268
 269 \f
 270
 271 // Allocate some unscanned memory and throw an exception if no memory.
 272 void *
 273 _Jv_AllocBytesChecked (jsize size)
 274 {
 275   void *r = _Jv_AllocBytes (size);
 276   if (! r)
 277     _Jv_Throw (no_memory);
 278   return r;
 279 }
 280
 281 // Allocate a new object of class C.  SIZE is the size of the object
 282 // to allocate.  You might think this is redundant, but it isn't; some
 283 // classes, such as String, aren't of fixed size.
 284 jobject
 285 _Jv_AllocObject (jclass c, jint size)
 286 {
 287   _Jv_InitClass (c);
 288
 289   jobject obj = (jobject) _Jv_AllocObj (size);
 290   if (! obj)
 291     JvThrow (no_memory);
 292   *((_Jv_VTable **) obj) = c->vtable;
 293
 294   // If this class has inherited finalize from Object, then don't
 295   // bother registering a finalizer.  We know that finalize() is the
 296   // very first method after the dummy entry.  If this turns out to be
 297   // unreliable, a more robust implementation can be written.  Such an
 298   // implementation would look for Object.finalize in Object's method
 299   // table at startup, and then use that information to find the
 300   // appropriate index in the method vector.
 301   if (c->vtable->method[1] != ObjectClass.vtable->method[1])
 302     _Jv_RegisterFinalizer (obj, _Jv_FinalizeObject);
 303
 304   return obj;
 305 }
 306
 307 // Allocate a new array of Java objects.  Each object is of type
 308 // `elementClass'.  `init' is used to initialize each slot in the
 309 // array.
 310 jobjectArray
 311 _Jv_NewObjectArray (jsize count, jclass elementClass, jobject init)
 312 {
 313   if (count < 0)
 314     JvThrow (new java::lang::NegativeArraySizeException);
 315
 316   // Check for overflow.
 317   if ((size_t) count > (SIZE_T_MAX - sizeof (__JArray)) / sizeof (jobject))
 318     JvThrow (no_memory);
 319
 320   size_t size = count * sizeof (jobject) + sizeof (__JArray);
 321
 322   // FIXME: second argument should be "current loader" //
 323   jclass clas = _Jv_FindArrayClass (elementClass, 0);
 324
 325   jobjectArray obj = (jobjectArray) _Jv_AllocArray (size);
 326   if (! obj)
 327     JvThrow (no_memory);
 328   obj->length = count;
 329   jobject* ptr = elements(obj);
 330   // We know the allocator returns zeroed memory.  So don't bother
 331   // zeroing it again.
 332   if (init)
 333     {
 334       while (--count >= 0)
 335         *ptr++ = init;
 336     }
 337   // Set the vtbl last to avoid problems if the GC happens during the
 338   // window in this function between the allocation and this
 339   // assignment.
 340   *((_Jv_VTable **) obj) = clas->vtable;
 341   return obj;
 342 }
 343
 344 // Allocate a new array of primitives.  ELTYPE is the type of the
 345 // element, COUNT is the size of the array.
 346 jobject
 347 _Jv_NewPrimArray (jclass eltype, jint count)
 348 {
 349   int elsize = eltype->size();
 350   if (count < 0)
 351     JvThrow (new java::lang::NegativeArraySizeException ());
 352
 353   // Check for overflow.
 354   if ((size_t) count > (SIZE_T_MAX - sizeof (__JArray)) / elsize)
 355     JvThrow (no_memory);
 356
 357   __JArray *arr = (__JArray*) _Jv_AllocObj (sizeof (__JArray)
 358                                             + elsize * count);
 359   if (! arr)
 360     JvThrow (no_memory);
 361   arr->length = count;
 362   // Note that we assume we are given zeroed memory by the allocator.
 363
 364   jclass klass = _Jv_FindArrayClass (eltype, 0);
 365   // Set the vtbl last to avoid problems if the GC happens during the
 366   // window in this function between the allocation and this
 367   // assignment.
 368   *((_Jv_VTable **) arr) = klass->vtable;
 369   return arr;
 370 }
 371
 372 jcharArray
 373 JvNewCharArray (jint length)
 374 {
 375   return (jcharArray) _Jv_NewPrimArray (JvPrimClass (char), length);
 376 }
 377
 378 jbooleanArray
 379 JvNewBooleanArray (jint length)
 380 {
 381   return (jbooleanArray) _Jv_NewPrimArray (JvPrimClass (boolean), length);
 382 }
 383
 384 jbyteArray
 385 JvNewByteArray (jint length)
 386 {
 387   return (jbyteArray) _Jv_NewPrimArray (JvPrimClass (byte), length);
 388 }
 389
 390 jshortArray
 391 JvNewShortArray (jint length)
 392 {
 393   return (jshortArray) _Jv_NewPrimArray (JvPrimClass (short), length);
 394 }
 395
 396 jintArray
 397 JvNewIntArray (jint length)
 398 {
 399   return (jintArray) _Jv_NewPrimArray (JvPrimClass (int), length);
 400 }
 401
 402 jlongArray
 403 JvNewLongArray (jint length)
 404 {
 405   return (jlongArray) _Jv_NewPrimArray (JvPrimClass (long), length);
 406 }
 407
 408 jfloatArray
 409 JvNewFloatArray (jint length)
 410 {
 411   return (jfloatArray) _Jv_NewPrimArray (JvPrimClass (float), length);
 412 }
 413
 414 jdoubleArray
 415 JvNewDoubleArray (jint length)
 416 {
 417   return (jdoubleArray) _Jv_NewPrimArray (JvPrimClass (double), length);
 418 }
 419
 420 jobject
 421 _Jv_NewArray (jint type, jint size)
 422 {
 423   switch (type)
 424     {
 425       case  4:  return JvNewBooleanArray (size);
 426       case  5:  return JvNewCharArray (size);
 427       case  6:  return JvNewFloatArray (size);
 428       case  7:  return JvNewDoubleArray (size);
 429       case  8:  return JvNewByteArray (size);
 430       case  9:  return JvNewShortArray (size);
 431       case 10:  return JvNewIntArray (size);
 432       case 11:  return JvNewLongArray (size);
 433     }
 434   JvFail ("newarray - bad type code");
 435   return NULL;                  // Placate compiler.
 436 }
 437
 438 jobject
 439 _Jv_NewMultiArray (jclass type, jint dimensions, jint *sizes)
 440 {
 441   JvAssert (type->isArray());
 442   jclass element_type = type->getComponentType();
 443   jobject result;
 444   if (element_type->isPrimitive())
 445     result = _Jv_NewPrimArray (element_type, sizes[0]);
 446   else
 447     result = _Jv_NewObjectArray (sizes[0], element_type, NULL);
 448
 449   if (dimensions > 1)
 450     {
 451       JvAssert (! element_type->isPrimitive());
 452       JvAssert (element_type->isArray());
 453       jobject *contents = elements ((jobjectArray) result);
 454       for (int i = 0; i < sizes[0]; ++i)
 455         contents[i] = _Jv_NewMultiArray (element_type, dimensions - 1,
 456                                          sizes + 1);
 457     }
 458
 459   return result;
 460 }
 461
 462 jobject
 463 _Jv_NewMultiArray (jclass array_type, jint dimensions, ...)
 464 {
 465   va_list args;
 466   jint sizes[dimensions];
 467   va_start (args, dimensions);
 468   for (int i = 0; i < dimensions; ++i)
 469     {
 470       jint size = va_arg (args, jint);
 471       sizes[i] = size;
 472     }
 473   va_end (args);
 474
 475   return _Jv_NewMultiArray (array_type, dimensions, sizes);
 476 }
 477
 478 \f
 479
 480 class _Jv_PrimClass : public java::lang::Class
 481 {
 482 public:
 483   // FIXME: calling convention is weird.  If we use the natural types
 484   // then the compiler will complain because they aren't Java types.
 485   _Jv_PrimClass (jobject cname, jbyte sig, jint len)
 486     {
 487       using namespace java::lang::reflect;
 488
 489       // We must initialize every field of the class.  We do this in
 490       // the same order they are declared in Class.h.
 491       next = NULL;
 492       name = _Jv_makeUtf8Const ((char *) cname, -1);
 493       accflags = Modifier::PUBLIC | Modifier::FINAL;
 494       superclass = NULL;
 495       constants.size = 0;
 496       constants.tags = NULL;
 497       constants.data = NULL;
 498       methods = NULL;
 499       method_count = sig;
 500       vtable_method_count = 0;
 501       fields = NULL;
 502       size_in_bytes = len;
 503       field_count = 0;
 504       static_field_count = 0;
 505       vtable = JV_PRIMITIVE_VTABLE;
 506       interfaces = NULL;
 507       loader = NULL;
 508       interface_count = 0;
 509       state = 0;                // FIXME.
 510       thread = NULL;
 511     }
 512 };
 513
 514 #define DECLARE_PRIM_TYPE(NAME, SIG, LEN) \
 515   _Jv_PrimClass _Jv_##NAME##Class((jobject) #NAME, (jbyte) SIG, (jint) LEN)
 516
 517 DECLARE_PRIM_TYPE(byte, 'B', 1);
 518 DECLARE_PRIM_TYPE(short, 'S', 2);
 519 DECLARE_PRIM_TYPE(int, 'I', 4);
 520 DECLARE_PRIM_TYPE(long, 'J', 8);
 521 DECLARE_PRIM_TYPE(boolean, 'Z', 1);
 522 DECLARE_PRIM_TYPE(char, 'C', 2);
 523 DECLARE_PRIM_TYPE(float, 'F', 4);
 524 DECLARE_PRIM_TYPE(double, 'D', 8);
 525 DECLARE_PRIM_TYPE(void, 'V', 0);
 526
 527 jclass
 528 _Jv_FindClassFromSignature (char *sig, java::lang::ClassLoader *loader)
 529 {
 530   switch (*sig)
 531     {
 532     case 'B':
 533       return JvPrimClass (byte);
 534     case 'S':
 535       return JvPrimClass (short);
 536     case 'I':
 537       return JvPrimClass (int);
 538     case 'J':
 539       return JvPrimClass (long);
 540     case 'Z':
 541       return JvPrimClass (boolean);
 542     case 'C':
 543       return JvPrimClass (char);
 544     case 'F':
 545       return JvPrimClass (float);
 546     case 'D':
 547       return JvPrimClass (double);
 548     case 'V':
 549       return JvPrimClass (void);
 550     case 'L':
 551       {
 552         int i;
 553         for (i = 1; sig[i] && sig[i] != ';'; ++i)
 554           ;
 555         _Jv_Utf8Const *name = _Jv_makeUtf8Const (&sig[1], i - 1);
 556         return _Jv_FindClass (name, loader);
 557
 558       }
 559     case '[':
 560       return _Jv_FindArrayClass (_Jv_FindClassFromSignature (&sig[1], loader),
 561                                  loader);
 562     }
 563   JvFail ("couldn't understand class signature");
 564   return NULL;                  // Placate compiler.
 565 }
 566
 567 \f
 568
 569 JArray<jstring> *
 570 JvConvertArgv (int argc, const char **argv)
 571 {
 572   if (argc < 0)
 573     argc = 0;
 574   jobjectArray ar = JvNewObjectArray(argc, &StringClass, NULL);
 575   jobject* ptr = elements(ar);
 576   for (int i = 0;  i < argc;  i++)
 577     {
 578       const char *arg = argv[i];
 579       // FIXME - should probably use JvNewStringUTF.
 580       *ptr++ = JvNewStringLatin1(arg, strlen(arg));
 581     }
 582   return (JArray<jstring>*) ar;
 583 }
 584
 585 // FIXME: These variables are static so that they will be
 586 // automatically scanned by the Boehm collector.  This is needed
 587 // because with qthreads the collector won't scan the initial stack --
 588 // it will only scan the qthreads stacks.
 589
 590 // Command line arguments.
 591 static jobject arg_vec;
 592
 593 // The primary threadgroup.
 594 static java::lang::ThreadGroup *main_group;
 595
 596 // The primary thread.
 597 static java::lang::Thread *main_thread;
 598
 599 static void
 600 main_init (void)
 601 {
 602   INIT_SEGV;
 603 #ifdef HANDLE_FPE
 604   INIT_FPE;
 605 #else
 606   arithexception = new java::lang::ArithmeticException
 607     (JvNewStringLatin1 ("/ by zero"));
 608 #endif
 609
 610   no_memory = new java::lang::OutOfMemoryError;
 611
 612 #ifdef USE_LTDL
 613   LTDL_SET_PRELOADED_SYMBOLS ();
 614 #endif
 615
 616   // FIXME: we only want this on POSIX systems.
 617   struct sigaction act;
 618   act.sa_handler = SIG_IGN;
 619   sigemptyset (&act.sa_mask);
 620   act.sa_flags = 0;
 621   sigaction (SIGPIPE, &act, NULL);
 622 }
 623
 624 void
 625 JvRunMain (jclass klass, int argc, const char **argv)
 626 {
 627   main_init ();
 628
 629   arg_vec = JvConvertArgv (argc - 1, argv + 1);
 630   main_group = new java::lang::ThreadGroup (23);
 631   main_thread = new java::lang::FirstThread (main_group, klass, arg_vec);
 632
 633   main_thread->start();
 634   _Jv_ThreadWait ();
 635
 636   java::lang::Runtime::getRuntime ()->exit (0);
 637 }
 638
 639 void
 640 _Jv_RunMain (const char *class_name, int argc, const char **argv)
 641 {
 642   main_init ();
 643
 644   arg_vec = JvConvertArgv (argc - 1, argv + 1);
 645   main_group = new java::lang::ThreadGroup (23);
 646   main_thread = new java::lang::FirstThread (main_group,
 647                                              JvNewStringLatin1 (class_name),
 648                                              arg_vec);
 649   main_thread->start();
 650   _Jv_ThreadWait ();
 651
 652   java::lang::Runtime::getRuntime ()->exit (0);
 653 }
 654
 655
 656 \f
 657
 658 void *
 659 _Jv_Malloc (jsize size)
 660 {
 661   if (size == 0)
 662     size = 1;
 663   void *ptr = malloc ((size_t) size);
 664   if (ptr == NULL)
 665     JvThrow (no_memory);
 666   return ptr;
 667 }
 668
 669 void
 670 _Jv_Free (void* ptr)
 671 {
 672   return free (ptr);
 673 }
 674
 675 \f
 676
 677 // In theory, these routines can be #ifdef'd away on machines which
 678 // support divide overflow signals.  However, we never know if some
 679 // code might have been compiled with "-fuse-divide-subroutine", so we
 680 // always include them in libgcj.
 681
 682 jint
 683 _Jv_divI (jint dividend, jint divisor)
 684 {
 685   if (divisor == 0)
 686     _Jv_Throw (arithexception);
 687
 688   if (dividend == (jint) 0x80000000L && divisor == -1)
 689     return dividend;
 690
 691   return dividend / divisor;
 692 }
 693
 694 jint
 695 _Jv_remI (jint dividend, jint divisor)
 696 {
 697   if (divisor == 0)
 698     _Jv_Throw (arithexception);
 699
 700   if (dividend == (jint) 0x80000000L && divisor == -1)
 701     return 0;
 702
 703   return dividend % divisor;
 704 }
 705
 706 jlong
 707 _Jv_divJ (jlong dividend, jlong divisor)
 708 {
 709   if (divisor == 0)
 710     _Jv_Throw (arithexception);
 711
 712   if (dividend == (jlong) 0x8000000000000000LL && divisor == -1)
 713     return dividend;
 714
 715   return dividend / divisor;
 716 }
 717
 718 jlong
 719 _Jv_remJ (jlong dividend, jlong divisor)
 720 {
 721   if (divisor == 0)
 722     _Jv_Throw (arithexception);
 723
 724   if (dividend == (jlong) 0x8000000000000000LL && divisor == -1)
 725     return 0;
 726
 727   return dividend % divisor;
 728 }
 729
 730
 731
 732
 733
 734
 735