jcf-parse.c

gcc-2.95.3 Linux下最常用的C编译器

   - and then perhaps rename read_class to load_class.  FIXME */

void
load_class (class_or_name, verbose)
     tree class_or_name;
     int verbose;
{
  tree name;

  /* class_or_name can be the name of the class we want to load */
  if (TREE_CODE (class_or_name) == IDENTIFIER_NODE)
    name = class_or_name;
  /* In some cases, it's a dependency that we process earlier that
     we though */
  else if (TREE_CODE (class_or_name) == TREE_LIST)
    name = TYPE_NAME (TREE_PURPOSE (class_or_name));
  /* Or it's a type in the making */
  else
    name = DECL_NAME (TYPE_NAME (class_or_name));

  if (read_class (name) == 0 && verbose)
    {
      error ("Cannot find file for class %s.",
	     IDENTIFIER_POINTER (name));
      if (TREE_CODE (class_or_name) == RECORD_TYPE)
	TYPE_SIZE (class_or_name) = error_mark_node;
#if 0
      /* FIXME: what to do here?  */
      if (!strcmp (classpath, DEFAULT_CLASS_PATH))
	fatal ("giving up");
#endif
      return;
    }
}

/* Parse a source file when JCF refers to a source file.  */

static void
jcf_parse_source ()
{
  tree file;

  java_parser_context_save_global ();
  java_push_parser_context ();
  input_filename = current_jcf->filename;
  file = get_identifier (input_filename);
  if (!HAS_BEEN_ALREADY_PARSED_P (file))
    {
      if (!(finput = fopen (input_filename, "r")))
	fatal ("input file `%s' just disappeared - jcf_parse_source",
	       input_filename);
      parse_source_file (file);
      if (fclose (finput))
	fatal ("can't close input file `%s' stream - jcf_parse_source",
	       input_filename);
    }
  java_pop_parser_context (IS_A_COMMAND_LINE_FILENAME_P (file));
  java_parser_context_restore_global ();
}

/* Parse the .class file JCF. */

void
jcf_parse (jcf)
     JCF* jcf;
{
  int i, code;

  if (jcf_parse_preamble (jcf) != 0)
    fatal ("Not a valid Java .class file.\n");
  code = jcf_parse_constant_pool (jcf);
  if (code != 0)
    fatal ("error while parsing constant pool");
  code = verify_constant_pool (jcf);
  if (code > 0)
    fatal ("error in constant pool entry #%d\n", code);

  jcf_parse_class (jcf);
  if (main_class == NULL_TREE)
    main_class = current_class;
  if (! quiet_flag && TYPE_NAME (current_class))
    fprintf (stderr, " class %s",
	     IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (current_class))));
  if (CLASS_LOADED_P (current_class))
    return;
  CLASS_LOADED_P (current_class) = 1;

  for (i = 1; i < JPOOL_SIZE(jcf); i++)
    {
      switch (JPOOL_TAG (jcf, i))
	{
	case CONSTANT_Class:
	  get_class_constant (jcf, i);
	  break;
	}
    }
  
  code = jcf_parse_fields (jcf);
  if (code != 0)
    fatal ("error while parsing fields");
  code = jcf_parse_methods (jcf);
  if (code != 0)
    fatal ("error while parsing methods");
  code = jcf_parse_final_attributes (jcf);
  if (code != 0)
    fatal ("error while parsing final attributes");

  /* The fields of class_type_node are already in correct order. */
  if (current_class != class_type_node && current_class != object_type_node)
    TYPE_FIELDS (current_class) = nreverse (TYPE_FIELDS (current_class));

  push_obstacks (&permanent_obstack, &permanent_obstack);
  layout_class (current_class);
  if (current_class == object_type_node)
    layout_class_methods (object_type_node);
  else
    all_class_list = tree_cons (NULL_TREE, 
				TYPE_NAME (current_class), all_class_list );
  pop_obstacks ();
}

void
init_outgoing_cpool ()
{
  current_constant_pool_data_ref = NULL_TREE; 
  if (outgoing_cpool == NULL)
    {
      static CPool outgoing_cpool_buffer;
      outgoing_cpool = &outgoing_cpool_buffer;
      CPOOL_INIT(outgoing_cpool);
    }
  else
    {
      CPOOL_REINIT(outgoing_cpool);
    }
}

static void
parse_class_file ()
{
  tree method;
  char *save_input_filename = input_filename;
  int save_lineno = lineno;

  java_layout_seen_class_methods ();

  input_filename = DECL_SOURCE_FILE (TYPE_NAME (current_class));
  lineno = 0;
  debug_start_source_file (input_filename);
  init_outgoing_cpool ();

  for ( method = TYPE_METHODS (CLASS_TO_HANDLE_TYPE (current_class));
	method != NULL_TREE; method = TREE_CHAIN (method))
    {
      JCF *jcf = current_jcf;

      if (METHOD_NATIVE (method) || METHOD_ABSTRACT (method))
	continue;

      if (DECL_CODE_OFFSET (method) == 0)
	{
	  error ("missing Code attribute");
	  continue;
	}

      lineno = 0;
      if (DECL_LINENUMBERS_OFFSET (method))
	{
	  register int i;
	  register unsigned char *ptr;
	  JCF_SEEK (jcf, DECL_LINENUMBERS_OFFSET (method));
	  linenumber_count = i = JCF_readu2 (jcf);
	  linenumber_table = ptr = jcf->read_ptr;

	  for (ptr += 2; --i >= 0; ptr += 4)
	    {
	      int line = GET_u2 (ptr);
	      /* Set initial lineno lineno to smallest linenumber.
	       * Needs to be set before init_function_start. */
	      if (lineno == 0 || line < lineno)
		lineno = line;
	    }  
	}
      else
	{
	  linenumber_table = NULL;
	  linenumber_count = 0;
	}

      start_java_method (method);

      give_name_to_locals (jcf);

      /* Actually generate code. */
      expand_byte_code (jcf, method);

      end_java_method ();
    }

  if (flag_emit_class_files)
    write_classfile (current_class);

  finish_class (current_class);

  debug_end_source_file (save_lineno);
  input_filename = save_input_filename;
  lineno = save_lineno;
}

/* Parse a source file, as pointed by the current value of INPUT_FILENAME. */

static void
parse_source_file (file)
     tree file;
{
  int save_error_count = java_error_count;
  /* Mark the file as parsed */
  HAS_BEEN_ALREADY_PARSED_P (file) = 1;

  lang_init_source (1);		    /* Error msgs have no method prototypes */

  java_init_lex ();		    /* Initialize the parser */
  java_parse_abort_on_error ();

  java_parse ();		    /* Parse and build partial tree nodes. */
  java_parse_abort_on_error ();
  java_complete_class ();	    /* Parse unsatisfied class decl. */
  java_parse_abort_on_error ();
  java_check_circular_reference (); /* Check on circular references */
  java_parse_abort_on_error ();
}

static int
predefined_filename_p (node)
     tree node;
{
  int i;
  for (i = 0; i < predef_filenames_size; i++)
    if (predef_filenames [i] == node)
      return 1;
  return 0;
}

int
yyparse ()
{
  int several_files = 0;
  char *list = strdup (input_filename), *next;
  tree node, current_file_list = NULL_TREE;

  do 
    {
      next = strchr (list, '&');
      if (next)
	{
	  *next++ = '\0';
	  several_files = 1;
	}

      if (list[0]) 
	{
	  char *value;
	  tree id;
	  int twice = 0;

	  int len = strlen (list);
	  /* FIXME: this test is only needed until our .java parser is
	     fully capable.  */
	  if (len > 5 && ! strcmp (&list[len - 5], ".java"))
	    saw_java_source = 1;

	  if (*list != '/' && several_files)
	    obstack_grow (&temporary_obstack, "./", 2);

	  obstack_grow0 (&temporary_obstack, list, len);
	  value = obstack_finish (&temporary_obstack);

	  /* Exclude file that we see twice on the command line. For
	     all files except {Class,Error,Object,RuntimeException,String,
	     Throwable}.java we can rely on maybe_get_identifier. For
	     these files, we need to do a linear search of
	     current_file_list. This search happens only for these
	     files, presumably only when we're recompiling libgcj. */
	     
	  if ((id = maybe_get_identifier (value)))
	    {
	      if (predefined_filename_p (id))
		{
		  tree c;
		  for (c = current_file_list; c; c = TREE_CHAIN (c))
		    if (TREE_VALUE (c) == id)
		      twice = 1;
		}
	      else
		twice = 1;
	    }

	  if (twice)
	    {
	      char *saved_input_filename = input_filename;
	      input_filename = value;
	      warning ("source file seen twice on command line and will be "
		       "compiled only once.");
	      input_filename = saved_input_filename;
	    }
	  else
	    {
	      node = get_identifier (value);
	      IS_A_COMMAND_LINE_FILENAME_P (node) = 1;
	      current_file_list = tree_cons (NULL_TREE, node, 
					     current_file_list);
	    }
	}
      list = next;
    }
  while (next);

  current_jcf = main_jcf;
  current_file_list = nreverse (current_file_list);
  for (node = current_file_list; node; node = TREE_CHAIN (node))
    {
      tree name = TREE_VALUE (node);

      /* Skip already parsed files */
      if (HAS_BEEN_ALREADY_PARSED_P (name))
	continue;
      
      /* Close previous descriptor, if any */
      if (main_jcf->read_state && fclose (main_jcf->read_state))
	fatal ("failed to close input file `%s' - yyparse",
	       (main_jcf->filename ? main_jcf->filename : "<unknown>"));
      
      /* Set jcf up and open a new file */
      JCF_ZERO (main_jcf);
      main_jcf->read_state = fopen (IDENTIFIER_POINTER (name), "rb");
      if (main_jcf->read_state == NULL)
	pfatal_with_name (IDENTIFIER_POINTER (name));
      
      /* Set new input_filename and finput */
      finput = main_jcf->read_state;
#ifdef IO_BUFFER_SIZE
      setvbuf (finput, (char *) xmalloc (IO_BUFFER_SIZE),
	       _IOFBF, IO_BUFFER_SIZE);
#endif
      input_filename = IDENTIFIER_POINTER (name);
      main_jcf->filbuf = jcf_filbuf_from_stdio;

      switch (jcf_figure_file_type (current_jcf))
	{
	case JCF_ZIP:
	  parse_zip_file_entries ();
	  break;
	case JCF_CLASS:
	  jcf_parse (current_jcf);
	  parse_class_file ();
	  break;
	case JCF_SOURCE:
	  java_push_parser_context ();
	  java_parser_context_save_global ();
	  parse_source_file (name);
	  java_parser_context_restore_global ();
	  java_pop_parser_context (1);
	  break;
	}
    }

  java_expand_classes ();
  if (!java_report_errors () && !flag_syntax_only)
    emit_register_classes ();
  return 0;
}

static struct ZipFileCache *localToFile;

/* Process all class entries found in the zip file.  */
static void
parse_zip_file_entries (void)
{
  struct ZipDirectory *zdir;
  int i;

  for (i = 0, zdir = (ZipDirectory *)localToFile->z.central_directory;
       i < localToFile->z.count; i++, zdir = ZIPDIR_NEXT (zdir))
    {
      tree class;
      
      /* We don't need to consider those files.  */
      if (!zdir->size || !zdir->filename_offset)
	continue;

      class = lookup_class (get_identifier (ZIPDIR_FILENAME (zdir)));
      current_jcf = TYPE_LANG_SPECIFIC (class)->jcf;
      current_class = class;

      if ( !CLASS_LOADED_P (class))
	{
          fseek (current_jcf->read_state, current_jcf->zip_offset, SEEK_SET);
	  jcf_parse (current_jcf);
	}

      if (TYPE_SIZE (current_class) != error_mark_node)
	{
	  input_filename = current_jcf->filename;
	  parse_class_file ();
	  FREE (current_jcf->buffer); /* No longer necessary */
	  /* Note: there is a way to free this buffer right after a
	     class seen in a zip file has been parsed. The idea is the
	     set its jcf in such a way that buffer will be reallocated
	     the time the code for the class will be generated. FIXME. */
	}
    }
}

/* Read all the entries of the zip file, creates a class and a JCF. Sets the
   jcf up for further processing and link it to the created class.  */

static void process_zip_dir()
{
  int i;
  ZipDirectory *zdir;

  for (i = 0, zdir = (ZipDirectory *)localToFile->z.central_directory;
       i < localToFile->z.count; i++, zdir = ZIPDIR_NEXT (zdir))
    {
      char *class_name, *file_name, *class_name_in_zip_dir;
      tree class;
      JCF  *jcf;
      int   j;

      class_name_in_zip_dir = ZIPDIR_FILENAME (zdir);

      /* We choose to not to process entries with a zero size or entries
	 not bearing the .class extention.  */
      if (!zdir->size || !zdir->filename_offset ||
	  strncmp (&class_name_in_zip_dir[zdir->filename_length-6], 
		   ".class", 6))
	{
	  /* So it will be skipped in parse_zip_file_entries  */
	  zdir->size = 0;  
	  continue;
	}

      class_name = ALLOC (zdir->filename_length+1-6);
      file_name  = ALLOC (zdir->filename_length+1);
      jcf = ALLOC (sizeof (JCF));
      JCF_ZERO (jcf);

      strncpy (class_name, class_name_in_zip_dir, zdir->filename_length-6);
      class_name [zdir->filename_length-6] = '\0';
      strncpy (file_name, class_name_in_zip_dir, zdir->filename_length);
      file_name [zdir->filename_length] = '\0';

      for (j=0; class_name[j]; j++)
        class_name [j] = (class_name [j] == '/' ? '.' : class_name [j]);

      /* Yes, we write back the true class name into the zip directory.  */
      strcpy (class_name_in_zip_dir, class_name);
      zdir->filename_length = j;
      class = lookup_class (get_identifier (class_name));

      jcf->read_state  = finput;
      jcf->filbuf      = jcf_filbuf_from_stdio;
      jcf->seen_in_zip = 1;
      jcf->java_source = 0;
      jcf->zip_offset  = zdir->filestart;
      jcf->classname   = class_name;
      jcf->filename    = file_name;

      TYPE_LANG_SPECIFIC (class) = 
        (struct lang_type *) perm_calloc (1, sizeof (struct lang_type));
      TYPE_LANG_SPECIFIC (class)->jcf = jcf;
    }
}

/* Lookup class NAME and figure whether is a class already found in the current
   zip file.  */
static int
DEFUN(find_in_current_zip, (name, length, jcf),
      char *name AND JCF **jcf)
{
  JCF *local_jcf;
  tree class_name = maybe_get_identifier (name), class, icv;

  if (!class_name)
    return 0;

  if (!(icv = IDENTIFIER_CLASS_VALUE (class_name)))
    return 0;

  class = TREE_TYPE (icv);

  /* Doesn't have jcf specific info ? It's not ours */
  if (!TYPE_LANG_SPECIFIC (class) || !TYPE_LANG_SPECIFIC (class)->jcf)
    return 0;

  *jcf = local_jcf = TYPE_LANG_SPECIFIC (class)->jcf;
  fseek (local_jcf->read_state, local_jcf->zip_offset, SEEK_SET);
  return 1;
}

/* Figure what kind of file we're dealing with */
static int
DEFUN(jcf_figure_file_type, (jcf),
      JCF *jcf)
{
  unsigned char magic_string[4];
  uint32 magic;

  if (fread (magic_string, 1, 4, jcf->read_state) != 4)
    jcf_unexpected_eof (jcf, 4);

  fseek (jcf->read_state, 0L, SEEK_SET);
  magic = GET_u4 (magic_string);

  if (magic == 0xcafebabe)
    return JCF_CLASS;

  /* FIXME: is it a system file?  */
  if (magic ==  (JCF_u4)ZIPMAGIC
      && !open_in_zip (jcf, input_filename, NULL, 0))
    {
      localToFile = ALLOC (sizeof (struct ZipFileCache));
      bcopy ((PTR) SeenZipFiles, (PTR) localToFile, sizeof (struct ZipFileCache));
      process_zip_dir ();	/* Register all the class defined there */
      return JCF_ZIP;
    }

  return JCF_SOURCE;
}