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