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