gcc/java/jcf-reader.c

   1 /* This file read a Java(TM) .class file.
   2    It is not stand-alone:  It depends on tons of macros, and the
   3    intent is you #include this file after you've defined the macros.
   4    Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003
   5    Free Software Foundation, Inc.
   6
   7 This file is part of GCC.
   8
   9 GCC is free software; you can redistribute it and/or modify
  10 it under the terms of the GNU General Public License as published by
  11 the Free Software Foundation; either version 2, or (at your option)
  12 any later version.
  13
  14 GCC is distributed in the hope that it will be useful,
  15 but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 GNU General Public License for more details.
  18
  19 You should have received a copy of the GNU General Public License
  20 along with GCC; see the file COPYING.  If not, write to
  21 the Free Software Foundation, 59 Temple Place - Suite 330,
  22 Boston, MA 02111-1307, USA.
  23
  24 Java and all Java-based marks are trademarks or registered trademarks
  25 of Sun Microsystems, Inc. in the United States and other countries.
  26 The Free Software Foundation is independent of Sun Microsystems, Inc.  */
  27
  28 #include "jcf.h"
  29 #include "zipfile.h"
  30
  31 static int get_attribute (JCF *);
  32 static int jcf_parse_preamble (JCF *);
  33 static int jcf_parse_constant_pool (JCF *);
  34 static void jcf_parse_class (JCF *);
  35 static int jcf_parse_fields (JCF *);
  36 static int jcf_parse_one_method (JCF *);
  37 static int jcf_parse_methods (JCF *);
  38 static int jcf_parse_final_attributes (JCF *);
  39 #ifdef NEED_PEEK_ATTRIBUTE
  40 static int peek_attribute (JCF *, int, const char *, int);
  41 #endif
  42 #ifdef NEED_SKIP_ATTRIBUTE
  43 static void skip_attribute (JCF *, int);
  44 #endif
  45
  46 /* Go through all available attribute (ATTRIBUTE_NUMER) and try to
  47    identify PEEKED_NAME.  Return 1 if PEEKED_NAME was found, 0
  48    otherwise. JCF is restored to its initial position before
  49    returning.  */
  50
  51 #ifdef NEED_PEEK_ATTRIBUTE      /* Not everyone uses this function */
  52 static int
  53 peek_attribute (JCF *jcf, int attribute_number, const char *peeked_name,
  54                 int peeked_name_length)
  55 {
  56   int to_return = 0;
  57   long absolute_offset = (long)JCF_TELL (jcf);
  58   int i;
  59
  60   for (i = 0; !to_return && i < attribute_number; i++)
  61     {
  62       uint16 attribute_name = (JCF_FILL (jcf, 6), JCF_readu2 (jcf));
  63       uint32 attribute_length = JCF_readu4 (jcf);
  64       int name_length;
  65       const unsigned char *name_data;
  66
  67       JCF_FILL (jcf, (long) attribute_length);
  68       if (attribute_name <= 0 || attribute_name >= JPOOL_SIZE(jcf)
  69           || JPOOL_TAG (jcf, attribute_name) != CONSTANT_Utf8)
  70         continue;
  71
  72       name_length = JPOOL_UTF_LENGTH (jcf, attribute_name);
  73       name_data = JPOOL_UTF_DATA (jcf, attribute_name);
  74
  75       if (name_length == peeked_name_length
  76           && ! memcmp (name_data, peeked_name, peeked_name_length))
  77         {
  78           to_return = 1;
  79           break;
  80         }
  81
  82       JCF_SKIP (jcf, attribute_length);
  83     }
  84
  85   JCF_SEEK (jcf, absolute_offset);
  86   return to_return;
  87 }
  88 #endif
  89
  90 #ifdef NEED_SKIP_ATTRIBUTE      /* Not everyone uses this function */
  91 static void
  92 skip_attribute (JCF *jcf, int number_of_attribute)
  93 {
  94   while (number_of_attribute--)
  95     {
  96       JCF_u4 N;
  97       JCF_FILL (jcf, 6);
  98       (void) JCF_readu2 (jcf);
  99       N = JCF_readu4 (jcf);
 100       JCF_SKIP (jcf, N);
 101     }
 102 }
 103 #endif
 104
 105 static int
 106 get_attribute (JCF *jcf)
 107 {
 108   uint16 attribute_name = (JCF_FILL (jcf, 6), JCF_readu2 (jcf));
 109   uint32 attribute_length = JCF_readu4 (jcf);
 110   uint32 start_pos = JCF_TELL(jcf);
 111   int name_length;
 112   const unsigned char *name_data;
 113   JCF_FILL (jcf, (long) attribute_length);
 114   if (attribute_name <= 0 || attribute_name >= JPOOL_SIZE(jcf))
 115     return -2;
 116   if (JPOOL_TAG (jcf, attribute_name) != CONSTANT_Utf8)
 117     return -2;
 118   name_length = JPOOL_UTF_LENGTH (jcf, attribute_name);
 119   name_data = JPOOL_UTF_DATA (jcf, attribute_name);
 120
 121 #define MATCH_ATTRIBUTE(S) \
 122   (name_length == sizeof (S)-1 && memcmp (name_data, S, sizeof (S)-1) == 0)
 123
 124 #ifdef IGNORE_ATTRIBUTE
 125    if (IGNORE_ATTRIBUTE (jcf, attribute_name, attribute_length))
 126      {
 127        JCF_SKIP (jcf, attribute_length);
 128      }
 129    else
 130 #endif
 131 #ifdef HANDLE_SOURCEFILE
 132   if (MATCH_ATTRIBUTE ("SourceFile"))
 133     {
 134       uint16 sourcefile_index = JCF_readu2 (jcf);
 135       HANDLE_SOURCEFILE(sourcefile_index);
 136     }
 137   else
 138 #endif
 139 #ifdef HANDLE_CONSTANTVALUE
 140   if (MATCH_ATTRIBUTE ("ConstantValue"))
 141     {
 142       uint16 constantvalue_index = JCF_readu2 (jcf);
 143       if (constantvalue_index <= 0 || constantvalue_index >= JPOOL_SIZE(jcf))
 144         return -2;
 145       HANDLE_CONSTANTVALUE(constantvalue_index);
 146     }
 147   else
 148 #endif
 149 #ifdef HANDLE_CODE_ATTRIBUTE
 150   if (MATCH_ATTRIBUTE ("Code"))
 151     {
 152       uint16 j;
 153       uint16 max_stack ATTRIBUTE_UNUSED = JCF_readu2 (jcf);
 154       uint16 max_locals ATTRIBUTE_UNUSED = JCF_readu2 (jcf);
 155       uint32 code_length = JCF_readu4 (jcf);
 156       uint16 exception_table_length, attributes_count;
 157       if (code_length + 12 > attribute_length)
 158         return -1;
 159       HANDLE_CODE_ATTRIBUTE(max_stack, max_locals, code_length);
 160       JCF_SKIP (jcf, code_length);
 161       exception_table_length = JCF_readu2 (jcf);
 162       if (code_length + 8 * exception_table_length + 12 > attribute_length)
 163         return -1;
 164 #ifdef HANDLE_EXCEPTION_TABLE
 165       HANDLE_EXCEPTION_TABLE (jcf->read_ptr, exception_table_length);
 166 #endif
 167       JCF_SKIP (jcf, 2 * 4 * exception_table_length);
 168       attributes_count = JCF_readu2 (jcf);
 169       for (j = 0; j < attributes_count; j++)
 170         {
 171           int code = get_attribute (jcf);
 172           if (code != 0)
 173             return code;
 174         }
 175     }
 176   else
 177 #endif /* HANDLE_CODE_ATTRIBUTE */
 178 #ifdef HANDLE_EXCEPTIONS_ATTRIBUTE
 179   if (MATCH_ATTRIBUTE ("Exceptions"))
 180     {
 181       uint16 count = JCF_readu2 (jcf);
 182       HANDLE_EXCEPTIONS_ATTRIBUTE (count);
 183     }
 184   else
 185 #endif
 186 #ifdef HANDLE_LINENUMBERTABLE_ATTRIBUTE
 187   if (MATCH_ATTRIBUTE ("LineNumberTable"))
 188     {
 189       uint16 count = JCF_readu2 (jcf);
 190       HANDLE_LINENUMBERTABLE_ATTRIBUTE (count);
 191     }
 192   else
 193 #endif
 194 #ifdef HANDLE_LOCALVARIABLETABLE_ATTRIBUTE
 195   if (MATCH_ATTRIBUTE ("LocalVariableTable"))
 196     {
 197       uint16 count = JCF_readu2 (jcf);
 198       HANDLE_LOCALVARIABLETABLE_ATTRIBUTE (count);
 199     }
 200   else
 201 #endif
 202 #ifdef HANDLE_INNERCLASSES_ATTRIBUTE
 203   if (MATCH_ATTRIBUTE ("InnerClasses"))
 204     {
 205       uint16 count = JCF_readu2 (jcf);
 206       HANDLE_INNERCLASSES_ATTRIBUTE (count);
 207     }
 208   else
 209 #endif
 210 #ifdef HANDLE_SYNTHETIC_ATTRIBUTE
 211   if (MATCH_ATTRIBUTE ("Synthetic"))
 212     {
 213       HANDLE_SYNTHETIC_ATTRIBUTE ();
 214     }
 215   else
 216 #endif
 217 #ifdef HANDLE_GCJCOMPILED_ATTRIBUTE
 218   if (MATCH_ATTRIBUTE ("gnu.gcj.gcj-compiled"))
 219     {
 220       HANDLE_GCJCOMPILED_ATTRIBUTE ();
 221     }
 222   else
 223 #endif
 224     {
 225 #ifdef PROCESS_OTHER_ATTRIBUTE
 226       PROCESS_OTHER_ATTRIBUTE(jcf, attribute_name, attribute_length);
 227 #else
 228       JCF_SKIP (jcf, attribute_length);
 229 #endif
 230     }
 231   if ((long) (start_pos + attribute_length) != JCF_TELL(jcf))
 232     return -1;
 233   return 0;
 234 }
 235
 236 /* Read and handle the pre-amble. */
 237 static int
 238 jcf_parse_preamble (JCF* jcf)
 239 {
 240   uint32 magic = (JCF_FILL (jcf, 8), JCF_readu4 (jcf));
 241   uint16 minor_version ATTRIBUTE_UNUSED = JCF_readu2 (jcf);
 242   uint16 major_version ATTRIBUTE_UNUSED = JCF_readu2 (jcf);
 243 #ifdef HANDLE_MAGIC
 244   HANDLE_MAGIC (magic, minor_version, major_version);
 245 #endif
 246   if (magic != 0xcafebabe)
 247     return -1;
 248   else
 249     return 0;
 250 }
 251
 252 /* Read and handle the constant pool.
 253
 254    Return 0 if OK.
 255    Return -2 if a bad cross-reference (index of other constant) was seen.
 256 */
 257 static int
 258 jcf_parse_constant_pool (JCF* jcf)
 259 {
 260   int i, n;
 261   JPOOL_SIZE (jcf) = (JCF_FILL (jcf, 2), JCF_readu2 (jcf));
 262   jcf->cpool.tags = ggc_alloc (JPOOL_SIZE (jcf));
 263   jcf->cpool.data = ggc_alloc (sizeof (jword) * JPOOL_SIZE (jcf));
 264   jcf->cpool.tags[0] = 0;
 265 #ifdef HANDLE_START_CONSTANT_POOL
 266   HANDLE_START_CONSTANT_POOL (JPOOL_SIZE (jcf));
 267 #endif
 268   for (i = 1; i < (int) JPOOL_SIZE (jcf); i++)
 269     {
 270       int constant_kind;
 271
 272       /* Make sure at least 9 bytes are available.  This is enough
 273          for all fixed-sized constant pool entries (so we don't need many
 274          more JCF_FILL calls below), but is is small enough that
 275          we are guaranteed to not hit EOF (in a valid .class file). */
 276       JCF_FILL (jcf, 9);
 277       constant_kind = JCF_readu (jcf);
 278       jcf->cpool.tags[i] = constant_kind;
 279       switch (constant_kind)
 280         {
 281         case CONSTANT_String:
 282         case CONSTANT_Class:
 283           jcf->cpool.data[i].w = JCF_readu2 (jcf);
 284           break;
 285         case CONSTANT_Fieldref:
 286         case CONSTANT_Methodref:
 287         case CONSTANT_InterfaceMethodref:
 288         case CONSTANT_NameAndType:
 289           jcf->cpool.data[i].w = JCF_readu2 (jcf);
 290           jcf->cpool.data[i].w |= JCF_readu2 (jcf) << 16;
 291           break;
 292         case CONSTANT_Integer:
 293         case CONSTANT_Float:
 294           jcf->cpool.data[i].w = JCF_readu4 (jcf);
 295           break;
 296         case CONSTANT_Long:
 297         case CONSTANT_Double:
 298           jcf->cpool.data[i].w = JCF_readu4 (jcf);
 299           i++; /* These take up two spots in the constant pool */
 300           jcf->cpool.tags[i] = 0;
 301           jcf->cpool.data[i].w = JCF_readu4 (jcf);
 302           break;
 303         case CONSTANT_Utf8:
 304           n = JCF_readu2 (jcf);
 305           JCF_FILL (jcf, n);
 306 #ifdef HANDLE_CONSTANT_Utf8
 307           HANDLE_CONSTANT_Utf8(jcf, i, n);
 308 #else
 309           jcf->cpool.data[i].w = JCF_TELL(jcf) - 2;
 310           JCF_SKIP (jcf, n);
 311 #endif
 312           break;
 313         default:
 314           return i;
 315         }
 316     }
 317   return 0;
 318 }
 319
 320 /* Read various class flags and numbers. */
 321
 322 static void
 323 jcf_parse_class (JCF* jcf)
 324 {
 325   int i;
 326   uint16 interfaces_count;
 327   JCF_FILL (jcf, 8);
 328   jcf->access_flags = JCF_readu2 (jcf);
 329   jcf->this_class = JCF_readu2 (jcf);
 330   jcf->super_class = JCF_readu2 (jcf);
 331   interfaces_count = JCF_readu2 (jcf);
 332
 333 #ifdef HANDLE_CLASS_INFO
 334   HANDLE_CLASS_INFO(jcf->access_flags, jcf->this_class, jcf->super_class, interfaces_count);
 335 #endif
 336
 337   JCF_FILL (jcf, 2 * interfaces_count);
 338
 339   /* Read interfaces. */
 340   for (i = 0; i < interfaces_count; i++)
 341     {
 342       uint16 index ATTRIBUTE_UNUSED = JCF_readu2 (jcf);
 343 #ifdef HANDLE_CLASS_INTERFACE
 344       HANDLE_CLASS_INTERFACE (index);
 345 #endif
 346     }
 347 }
 348
 349 /* Read fields. */
 350 static int
 351 jcf_parse_fields (JCF* jcf)
 352 {
 353   int i, j;
 354   uint16 fields_count;
 355   JCF_FILL (jcf, 2);
 356   fields_count = JCF_readu2 (jcf);
 357
 358 #ifdef HANDLE_START_FIELDS
 359   HANDLE_START_FIELDS (fields_count);
 360 #endif
 361   for (i = 0; i < fields_count; i++)
 362     {
 363       uint16 access_flags = (JCF_FILL (jcf, 8), JCF_readu2 (jcf));
 364       uint16 name_index = JCF_readu2 (jcf);
 365       uint16 signature_index = JCF_readu2 (jcf);
 366       uint16 attribute_count = JCF_readu2 (jcf);
 367 #ifdef HANDLE_START_FIELD
 368       HANDLE_START_FIELD (access_flags, name_index, signature_index,
 369                           attribute_count);
 370 #endif
 371       for (j = 0; j < attribute_count; j++)
 372         {
 373           int code = get_attribute (jcf);
 374           if (code != 0)
 375             return code;
 376         }
 377 #ifdef HANDLE_END_FIELD
 378       HANDLE_END_FIELD ();
 379 #endif
 380     }
 381 #ifdef HANDLE_END_FIELDS
 382   HANDLE_END_FIELDS ();
 383 #endif
 384   return 0;
 385 }
 386
 387 /* Read methods. */
 388
 389 static int
 390 jcf_parse_one_method (JCF* jcf)
 391 {
 392   int i;
 393   uint16 access_flags = (JCF_FILL (jcf, 8), JCF_readu2 (jcf));
 394   uint16 name_index = JCF_readu2 (jcf);
 395   uint16 signature_index = JCF_readu2 (jcf);
 396   uint16 attribute_count = JCF_readu2 (jcf);
 397 #ifdef HANDLE_METHOD
 398   HANDLE_METHOD(access_flags, name_index, signature_index, attribute_count);
 399 #endif
 400   for (i = 0; i < attribute_count; i++)
 401     {
 402       int code = get_attribute (jcf);
 403       if (code != 0)
 404         return code;
 405     }
 406 #ifdef HANDLE_END_METHOD
 407   HANDLE_END_METHOD ();
 408 #endif
 409   return 0;
 410 }
 411
 412 static int
 413 jcf_parse_methods (JCF* jcf)
 414 {
 415   int i;
 416   uint16 methods_count;
 417   JCF_FILL (jcf, 2);
 418   methods_count = JCF_readu2 (jcf);
 419 #ifdef HANDLE_START_METHODS
 420   HANDLE_START_METHODS (methods_count);
 421 #endif
 422   for (i = 0; i < methods_count; i++)
 423     {
 424       int code = jcf_parse_one_method (jcf);
 425       if (code != 0)
 426         return code;
 427     }
 428 #ifdef HANDLE_END_METHODS
 429   HANDLE_END_METHODS ();
 430 #endif
 431   return 0;
 432 }
 433
 434 /* Read attributes. */
 435 static int
 436 jcf_parse_final_attributes (JCF *jcf)
 437 {
 438   int i;
 439   uint16 attributes_count = (JCF_FILL (jcf, 2), JCF_readu2 (jcf));
 440 #ifdef START_FINAL_ATTRIBUTES
 441   START_FINAL_ATTRIBUTES (attributes_count)
 442 #endif
 443   for (i = 0; i < attributes_count; i++)
 444     {
 445       int code = get_attribute (jcf);
 446       if (code != 0)
 447         return code;
 448     }
 449   return 0;
 450 }
 451