content: /*
   * [The "BSD licence"]
   * Copyright (c) 2010 Ben Gruver (JesusFreke)
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. The name of the author may not be used to endorse or promote products
   *    derived from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
   * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
   * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
   * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
   * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
   * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  package org.jf.dexlib;
  
  import org.jf.dexlib.Util.AnnotatedOutput;
  import org.jf.dexlib.Util.Input;
  import org.jf.dexlib.Util.Utf8Utils;
  
  public class HeaderItem extends Item<HeaderItem> {
      /**
       * the file format magic number, represented as the
       * low-order bytes of a string
       */
      public static final byte[] MAGIC = new byte[] {0x64, 0x65, 0x78, 0x0A, 0x30, 0x33, 0x35, 0x00};//"dex\n035" + '\0';
  
  
      /** size of this section, in bytes */
      private static final int HEADER_SIZE = 0x70;
  
      /** the endianness constants */
      private static final int LITTLE_ENDIAN = 0x12345678;
      private static final int BIG_ENDIAN = 0x78562312;
  
      /**
       * Create a new uninitialized <code>HeaderItem</code>
       * @param dexFile The <code>DexFile</code> containing this <code>HeaderItem</code>
       */
      protected HeaderItem(final DexFile dexFile) {
          super(dexFile);
      }
  
      /** {@inheritDoc} */
      protected void readItem(Input in, ReadContext readContext) {
          byte[] readMagic = in.readBytes(8);
  
          for (int i=0; i<8; i++) {
              if (MAGIC[i] != readMagic[i]) {
                  throw new RuntimeException("The magic value is not the expected value");
              }
          }
  
          in.readBytes(20); //checksum
          in.readInt(); //signature
          in.readInt(); //filesize
          if (in.readInt() != HEADER_SIZE) {
              throw new RuntimeException("The header size is not the expected value (0x70)");
          }
  
          int endianTag = in.readInt();
          if (endianTag == BIG_ENDIAN) {
              throw new RuntimeException("This dex file is big endian. Only little endian is currently supported.");
          } else if (endianTag != LITTLE_ENDIAN) {
              throw new RuntimeException("The endian tag is not 0x12345678 or 0x78563412");
          }
  
          //link_size + link_off
          if ((in.readInt() | in.readInt()) != 0) {
              System.err.println("This dex file has a link section, which is not supported. Ignoring.");
          }
  
          int sectionSize;
          int sectionOffset;
  
          //map_offset
          sectionOffset = in.readInt();
          readContext.addSection(ItemType.TYPE_MAP_LIST, 1, sectionOffset);
  
          //string_id_item
          sectionSize = in.readInt();
          sectionOffset = in.readInt();
          readContext.addSection(ItemType.TYPE_STRING_ID_ITEM, sectionSize, sectionOffset);
  
          //type_id_item
          sectionSize = in.readInt();
          sectionOffset = in.readInt();
          readContext.addSection(ItemType.TYPE_TYPE_ID_ITEM, sectionSize, sectionOffset);
  
          //proto_id_item
          sectionSize = in.readInt();
          sectionOffset = in.readInt();
          readContext.addSection(ItemType.TYPE_PROTO_ID_ITEM, sectionSize, sectionOffset);
  
          //field_id_item
          sectionSize = in.readInt();
          sectionOffset = in.readInt();
          readContext.addSection(ItemType.TYPE_FIELD_ID_ITEM, sectionSize, sectionOffset);
  
          //method_id_item
          sectionSize = in.readInt();
          sectionOffset = in.readInt();
          readContext.addSection(ItemType.TYPE_METHOD_ID_ITEM, sectionSize, sectionOffset);
  
          //class_data_item
          sectionSize = in.readInt();
          sectionOffset = in.readInt();
          readContext.addSection(ItemType.TYPE_CLASS_DEF_ITEM, sectionSize, sectionOffset);
  
          in.readInt(); //data_size
          in.readInt(); //data_off
      }
  
      /** {@inheritDoc} */
      protected int placeItem(int offset) {
          return HEADER_SIZE;
      }
  
      /** {@inheritDoc} */
      protected void writeItem(AnnotatedOutput out) {
          StringBuilder magicBuilder = new StringBuilder();
          for (int i=0; i<8; i++) {
              magicBuilder.append((char)MAGIC[i]);
          }
  
          out.annotate("magic: " + Utf8Utils.escapeString(magicBuilder.toString()));
          out.write(MAGIC);
  
          out.annotate("checksum");
          out.writeInt(0);
  
          out.annotate("signature");
          out.write(new byte[20]);
  
          out.annotate("file_size: 0x" + Integer.toHexString(dexFile.getFileSize()) + " (" + dexFile.getFileSize() +
                  " bytes)");
          out.writeInt(dexFile.getFileSize());
  
          out.annotate("header_size: 0x" + Integer.toHexString(HEADER_SIZE));
          out.writeInt(HEADER_SIZE);
  
          out.annotate("endian_tag: 0x" + Integer.toHexString(LITTLE_ENDIAN));
          out.writeInt(LITTLE_ENDIAN);
  
          out.annotate("link_size: 0");
          out.writeInt(0);
  
          out.annotate("link_off: 0");
          out.writeInt(0);
  
          out.annotate("map_off: 0x" + Integer.toHexString(dexFile.MapItem.getOffset()));
          out.writeInt(dexFile.MapItem.getOffset());
  
          out.annotate("string_ids_size: " + dexFile.StringIdsSection.getItems().size());
          out.writeInt(dexFile.StringIdsSection.getItems().size());
  
          out.annotate("string_ids_off: 0x" + Integer.toHexString(dexFile.StringIdsSection.getOffset()));
          out.writeInt(dexFile.StringIdsSection.getOffset());
  
          out.annotate("type_ids_size: " + dexFile.TypeIdsSection.getItems().size());
          out.writeInt(dexFile.TypeIdsSection.getItems().size());
  
          out.annotate("type_ids_off: 0x" + Integer.toHexString(dexFile.TypeIdsSection.getOffset()));
          out.writeInt(dexFile.TypeIdsSection.getOffset());
  
          out.annotate("proto_ids_size: " + dexFile.ProtoIdsSection.getItems().size());
          out.writeInt(dexFile.ProtoIdsSection.getItems().size());
  
          out.annotate("proto_ids_off: 0x" + Integer.toHexString(dexFile.ProtoIdsSection.getOffset()));
          out.writeInt(dexFile.ProtoIdsSection.getOffset());
  
          out.annotate("field_ids_size: " + dexFile.FieldIdsSection.getItems().size());
          out.writeInt(dexFile.FieldIdsSection.getItems().size());
  
          out.annotate("field_ids_off: 0x" + Integer.toHexString(dexFile.FieldIdsSection.getOffset()));
          out.writeInt(dexFile.FieldIdsSection.getOffset());
  
          out.annotate("method_ids_size: " + dexFile.MethodIdsSection.getItems().size());
          out.writeInt(dexFile.MethodIdsSection.getItems().size());
  
          out.annotate("method_ids_off: 0x" + Integer.toHexString(dexFile.MethodIdsSection.getOffset()));
          out.writeInt(dexFile.MethodIdsSection.getOffset());
  
          out.annotate("class_defs_size: " + dexFile.ClassDefsSection.getItems().size());
          out.writeInt(dexFile.ClassDefsSection.getItems().size());
  
          out.annotate("class_defs_off: 0x" + Integer.toHexString(dexFile.ClassDefsSection.getOffset()));
          out.writeInt(dexFile.ClassDefsSection.getOffset());
  
          out.annotate("data_size: 0x" + Integer.toHexString(dexFile.getDataSize()) + " (" + dexFile.getDataSize() +
                  " bytes)");
          out.writeInt(dexFile.getDataSize());
  
          out.annotate("data_off: 0x" + Integer.toHexString(dexFile.getDataOffset()));
          out.writeInt(dexFile.getDataOffset());
      }
  
      /** {@inheritDoc} */
      public ItemType getItemType() {
          return ItemType.TYPE_HEADER_ITEM;
      }
  
      /** {@inheritDoc} */
      public String getConciseIdentity() {
          return "header_item";
      }
  
      /** {@inheritDoc} */
      public int compareTo(HeaderItem o) {
          //there is only 1 header item
          return 0;
      }
  }
  