Home | History | Annotate | Download | only in dexlib 
      1 /*
      2  * [The "BSD licence"]
      3  * Copyright (c) 2010 Ben Gruver (JesusFreke)
      4  * All rights reserved.
      5  *
      6  * Redistribution and use in source and binary forms, with or without
      7  * modification, are permitted provided that the following conditions
      8  * are met:
      9  * 1. Redistributions of source code must retain the above copyright
     10  *    notice, this list of conditions and the following disclaimer.
     11  * 2. Redistributions in binary form must reproduce the above copyright
     12  *    notice, this list of conditions and the following disclaimer in the
     13  *    documentation and/or other materials provided with the distribution.
     14  * 3. The name of the author may not be used to endorse or promote products
     15  *    derived from this software without specific prior written permission.
     16  *
     17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     25  * INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     27  */
     28 
     29 package org.jf.dexlib;
     30 
     31 import org.jf.dexlib.Util.AnnotatedOutput;
     32 import org.jf.dexlib.Util.Input;
     33 
     34 /**
     35  * This item represents a map_list item from the dex specification. It contains a
     36  * SectionInfo instance for every section in the DexFile, with the number of items
     37  * in and offset of that section.
     38  */
     39 public class MapItem extends Item<MapItem> {
     40     /**
     41      * This item is read in immediately after the HeaderItem, and the section info contained
     42      * by this item is added to the ReadContext object, which is used when reading in the other
     43      * sections in the dex file.
     44      *
     45      * This item should be placed last. It depends on the fact that the other sections
     46      * in the file have been placed.
     47      */
     48 
     49     /**
     50      * Create a new uninitialized <code>MapItem</code>
     51      * @param dexFile The <code>DexFile</code> that this item belongs to
     52      */
     53     protected MapItem(final DexFile dexFile) {
     54         super(dexFile);
     55     }
     56 
     57     /** {@inheritDoc} */
     58     protected int placeItem(int offset) {
     59         Section[] sections = dexFile.getOrderedSections();
     60         //the list returned by getOrderedSections doesn't contain the header
     61         //or map section, so add 2 to the length
     62         return offset + 4 + (sections.length + 2) * 12;
     63     }
     64 
     65     /** {@inheritDoc} */
     66     protected void readItem(Input in, ReadContext readContext) {
     67         int size = in.readInt();
     68 
     69         for (int i=0; i<size; i++) {
     70             ItemType itemType = ItemType.fromInt(in.readShort());
     71 
     72             //unused
     73             in.readShort();
     74 
     75             int sectionSize = in.readInt();
     76             int sectionOffset = in.readInt();
     77 
     78             readContext.addSection(itemType, sectionSize, sectionOffset);
     79         }
     80     }
     81 
     82     /** {@inheritDoc} */
     83     protected void writeItem(AnnotatedOutput out) {
     84         assert getOffset() > 0;
     85         Section[] sections = dexFile.getOrderedSections();
     86 
     87         out.annotate("map_size: 0x" + Integer.toHexString(sections.length + 2) + " (" +
     88                 Integer.toString(sections.length + 2) + ")");
     89         out.writeInt(sections.length + 2);
     90 
     91         int index = 0;
     92         out.annotate(0, "[" + index++ + "]");
     93         out.indent();
     94         writeSectionInfo(out, ItemType.TYPE_HEADER_ITEM, 1, 0);
     95         out.deindent();
     96 
     97         for (Section section: dexFile.getOrderedSections()) {
     98             out.annotate(0, "[" + index++ + "]");
     99             out.indent();
    100             writeSectionInfo(out, section.ItemType, section.getItems().size(), section.getOffset());
    101             out.deindent();
    102         }
    103 
    104         out.annotate(0, "[" + index++ + "]");
    105         out.indent();
    106         writeSectionInfo(out, ItemType.TYPE_MAP_LIST, 1, dexFile.MapItem.getOffset());
    107         out.deindent();
    108     }
    109 
    110     private void writeSectionInfo(AnnotatedOutput out, ItemType itemType, int sectionSize, int sectionOffset) {
    111         if (out.annotates()) {
    112             out.annotate(2, "item_type: " + itemType);
    113             out.annotate(2, "unused");
    114             out.annotate(4, "section_size: 0x" + Integer.toHexString(sectionSize) + " (" + sectionSize + ")");
    115             out.annotate(4, "section_off: 0x" + Integer.toHexString(sectionOffset));
    116         }
    117 
    118         out.writeShort(itemType.MapValue);
    119         out.writeShort(0);
    120         out.writeInt(sectionSize);
    121         out.writeInt(sectionOffset);
    122     }
    123 
    124     /** {@inheritDoc} */
    125     public ItemType getItemType() {
    126         return ItemType.TYPE_MAP_LIST;
    127     }
    128 
    129     /** {@inheritDoc} */
    130     public int compareTo(MapItem o) {
    131         return 0;
    132     }
    133 
    134     /** {@inheritDoc} */
    135     public String getConciseIdentity() {
    136         return "map_item";
    137     }
    138 }
    139