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, 2005
   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, 51 Franklin Street, Fifth Floor,
  22 Boston, MA 02110-1301, 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 #ifdef HANDLE_DEPRECATED_ATTRIBUTE
 225   if (MATCH_ATTRIBUTE ("Deprecated"))
 226     {
 227       HANDLE_DEPRECATED_ATTRIBUTE ();
 228     }
 229   else
 230 #endif
 231 #ifdef HANDLE_SOURCEDEBUGEXTENSION_ATTRIBUTE
 232   if (MATCH_ATTRIBUTE ("SourceDebugExtension")) /* JSR 45 */
 233     {
 234       HANDLE_SOURCEDEBUGEXTENSION_ATTRIBUTE (attribute_length);
 235     }
 236   else
 237 #endif
 238     {
 239 #ifdef PROCESS_OTHER_ATTRIBUTE
 240       PROCESS_OTHER_ATTRIBUTE(jcf, attribute_name, attribute_length);
 241 #else
 242       JCF_SKIP (jcf, attribute_length);
 243 #endif
 244     }
 245   if ((long) (start_pos + attribute_length) != JCF_TELL(jcf))
 246     return -1;
 247   return 0;
 248 }
 249
 250 /* Read and handle the pre-amble. */
 251 static int
 252 jcf_parse_preamble (JCF* jcf)
 253 {
 254   uint32 magic = (JCF_FILL (jcf, 8), JCF_readu4 (jcf));
 255   uint16 minor_version ATTRIBUTE_UNUSED = JCF_readu2 (jcf);
 256   uint16 major_version ATTRIBUTE_UNUSED = JCF_readu2 (jcf);
 257 #ifdef HANDLE_MAGIC
 258   HANDLE_MAGIC (magic, minor_version, major_version);
 259 #endif
 260   if (magic != 0xcafebabe)
 261     return -1;
 262   else
 263     return 0;
 264 }
 265
 266 /* Read and handle the constant pool.
 267
 268    Return 0 if OK.
 269    Return -2 if a bad cross-reference (index of other constant) was seen.
 270 */
 271 static int
 272 jcf_parse_constant_pool (JCF* jcf)
 273 {
 274   int i, n;
 275   JPOOL_SIZE (jcf) = (JCF_FILL (jcf, 2), JCF_readu2 (jcf));
 276   jcf->cpool.tags = ggc_alloc (JPOOL_SIZE (jcf));
 277   jcf->cpool.data = ggc_alloc (sizeof (jword) * JPOOL_SIZE (jcf));
 278   jcf->cpool.tags[0] = 0;
 279 #ifdef HANDLE_START_CONSTANT_POOL
 280   HANDLE_START_CONSTANT_POOL (JPOOL_SIZE (jcf));
 281 #endif
 282   for (i = 1; i < (int) JPOOL_SIZE (jcf); i++)
 283     {
 284       int constant_kind;
 285
 286       /* Make sure at least 9 bytes are available.  This is enough
 287          for all fixed-sized constant pool entries (so we don't need many
 288          more JCF_FILL calls below), but is is small enough that
 289          we are guaranteed to not hit EOF (in a valid .class file). */
 290       JCF_FILL (jcf, 9);
 291       constant_kind = JCF_readu (jcf);
 292       jcf->cpool.tags[i] = constant_kind;
 293       switch (constant_kind)
 294         {
 295         case CONSTANT_String:
 296         case CONSTANT_Class:
 297           jcf->cpool.data[i].w = JCF_readu2 (jcf);
 298           break;
 299         case CONSTANT_Fieldref:
 300         case CONSTANT_Methodref:
 301         case CONSTANT_InterfaceMethodref:
 302         case CONSTANT_NameAndType:
 303           jcf->cpool.data[i].w = JCF_readu2 (jcf);
 304           jcf->cpool.data[i].w |= JCF_readu2 (jcf) << 16;
 305           break;
 306         case CONSTANT_Integer:
 307         case CONSTANT_Float:
 308           jcf->cpool.data[i].w = JCF_readu4 (jcf);
 309           break;
 310         case CONSTANT_Long:
 311         case CONSTANT_Double:
 312           jcf->cpool.data[i].w = JCF_readu4 (jcf);
 313           i++; /* These take up two spots in the constant pool */
 314           jcf->cpool.tags[i] = 0;
 315           jcf->cpool.data[i].w = JCF_readu4 (jcf);
 316           break;
 317         case CONSTANT_Utf8:
 318           n = JCF_readu2 (jcf);
 319           JCF_FILL (jcf, n);
 320 #ifdef HANDLE_CONSTANT_Utf8
 321           HANDLE_CONSTANT_Utf8(jcf, i, n);
 322 #else
 323           jcf->cpool.data[i].w = JCF_TELL(jcf) - 2;
 324           JCF_SKIP (jcf, n);
 325 #endif
 326           break;
 327         default:
 328           return i;
 329         }
 330     }
 331   return 0;
 332 }
 333
 334 /* Read various class flags and numbers. */
 335
 336 static void
 337 jcf_parse_class (JCF* jcf)
 338 {
 339   int i;
 340   uint16 interfaces_count;
 341   JCF_FILL (jcf, 8);
 342   jcf->access_flags = JCF_readu2 (jcf);
 343   jcf->this_class = JCF_readu2 (jcf);
 344   jcf->super_class = JCF_readu2 (jcf);
 345   interfaces_count = JCF_readu2 (jcf);
 346
 347 #ifdef HANDLE_CLASS_INFO
 348   HANDLE_CLASS_INFO(jcf->access_flags, jcf->this_class, jcf->super_class, interfaces_count);
 349 #endif
 350
 351   JCF_FILL (jcf, 2 * interfaces_count);
 352
 353   /* Read interfaces. */
 354   for (i = 0; i < interfaces_count; i++)
 355     {
 356       uint16 index ATTRIBUTE_UNUSED = JCF_readu2 (jcf);
 357 #ifdef HANDLE_CLASS_INTERFACE
 358       HANDLE_CLASS_INTERFACE (index);
 359 #endif
 360     }
 361 }
 362
 363 /* Read fields. */
 364 static int
 365 jcf_parse_fields (JCF* jcf)
 366 {
 367   int i, j;
 368   uint16 fields_count;
 369   JCF_FILL (jcf, 2);
 370   fields_count = JCF_readu2 (jcf);
 371
 372 #ifdef HANDLE_START_FIELDS
 373   HANDLE_START_FIELDS (fields_count);
 374 #endif
 375   for (i = 0; i < fields_count; i++)
 376     {
 377       uint16 access_flags = (JCF_FILL (jcf, 8), JCF_readu2 (jcf));
 378       uint16 name_index = JCF_readu2 (jcf);
 379       uint16 signature_index = JCF_readu2 (jcf);
 380       uint16 attribute_count = JCF_readu2 (jcf);
 381 #ifdef HANDLE_START_FIELD
 382       HANDLE_START_FIELD (access_flags, name_index, signature_index,
 383                           attribute_count);
 384 #endif
 385       for (j = 0; j < attribute_count; j++)
 386         {
 387           int code = get_attribute (jcf);
 388           if (code != 0)
 389             return code;
 390         }
 391 #ifdef HANDLE_END_FIELD
 392       HANDLE_END_FIELD ();
 393 #endif
 394     }
 395 #ifdef HANDLE_END_FIELDS
 396   HANDLE_END_FIELDS ();
 397 #endif
 398   return 0;
 399 }
 400
 401 /* Read methods. */
 402
 403 static int
 404 jcf_parse_one_method (JCF* jcf)
 405 {
 406   int i;
 407   uint16 access_flags = (JCF_FILL (jcf, 8), JCF_readu2 (jcf));
 408   uint16 name_index = JCF_readu2 (jcf);
 409   uint16 signature_index = JCF_readu2 (jcf);
 410   uint16 attribute_count = JCF_readu2 (jcf);
 411 #ifdef HANDLE_METHOD
 412   HANDLE_METHOD(access_flags, name_index, signature_index, attribute_count);
 413 #endif
 414   for (i = 0; i < attribute_count; i++)
 415     {
 416       int code = get_attribute (jcf);
 417       if (code != 0)
 418         return code;
 419     }
 420 #ifdef HANDLE_END_METHOD
 421   HANDLE_END_METHOD ();
 422 #endif
 423   return 0;
 424 }
 425
 426 static int
 427 jcf_parse_methods (JCF* jcf)
 428 {
 429   int i;
 430   uint16 methods_count;
 431   JCF_FILL (jcf, 2);
 432   methods_count = JCF_readu2 (jcf);
 433 #ifdef HANDLE_START_METHODS
 434   HANDLE_START_METHODS (methods_count);
 435 #endif
 436   for (i = 0; i < methods_count; i++)
 437     {
 438       int code = jcf_parse_one_method (jcf);
 439       if (code != 0)
 440         return code;
 441     }
 442 #ifdef HANDLE_END_METHODS
 443   HANDLE_END_METHODS ();
 444 #endif
 445   return 0;
 446 }
 447
 448 /* Read attributes. */
 449 static int
 450 jcf_parse_final_attributes (JCF *jcf)
 451 {
 452   int i;
 453   uint16 attributes_count = (JCF_FILL (jcf, 2), JCF_readu2 (jcf));
 454 #ifdef START_FINAL_ATTRIBUTES
 455   START_FINAL_ATTRIBUTES (attributes_count)
 456 #endif
 457   for (i = 0; i < attributes_count; i++)
 458     {
 459       int code = get_attribute (jcf);
 460       if (code != 0)
 461         return code;
 462     }
 463   return 0;
 464 }
 465