/*
* [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.ExceptionWithContext;
import org.jf.dexlib.Util.SparseArray;
import java.util.List;
/**
* This class stores context information that is only needed when reading in a dex file
* Namely, it handles "pre-creating" items when an item needs to resolve some other item
* that it references, and keeps track of those pre-created items, so the corresponding section
* for the pre-created items uses them, instead of creating new items
*/
public class ReadContext {
private SparseArray<TypeListItem> typeListItems = new SparseArray<TypeListItem>(0);
private SparseArray<AnnotationSetRefList> annotationSetRefLists = new SparseArray<AnnotationSetRefList>(0);
private SparseArray<AnnotationSetItem> annotationSetItems = new SparseArray<AnnotationSetItem>(0);
private SparseArray<ClassDataItem> classDataItems = new SparseArray<ClassDataItem>(0);
private SparseArray<CodeItem> codeItems = new SparseArray<CodeItem>(0);
private SparseArray<StringDataItem> stringDataItems = new SparseArray<StringDataItem>(0);
private SparseArray<DebugInfoItem> debugInfoItems = new SparseArray<DebugInfoItem>(0);
private SparseArray<AnnotationItem> annotationItems = new SparseArray<AnnotationItem>(0);
private SparseArray<EncodedArrayItem> encodedArrayItems = new SparseArray<EncodedArrayItem>(0);
private SparseArray<AnnotationDirectoryItem> annotationDirectoryItems = new SparseArray<AnnotationDirectoryItem>(0);
private SparseArray[] itemsByType = new SparseArray[] {
null, //string_id_item
null, //type_id_item
null, //proto_id_item
null, //field_id_item
null, //method_id_item
null, //class_def_item
typeListItems,
annotationSetRefLists,
annotationSetItems,
classDataItems,
codeItems,
stringDataItems,
debugInfoItems,
annotationItems,
encodedArrayItems,
annotationDirectoryItems,
null, //map_list
null //header_item
};
/**
* The section sizes that are passed in while reading HeaderItem/MapItem, via the
* addSection method.
*/
private int[] sectionSizes = new int[18];
/**
* The section offsets that are passed in while reading MapItem/HeaderItem, via the
* addSection method.
*/
private int[] sectionOffsets = new int[18];
/**
* Creates a new ReadContext instance.
*/
public ReadContext() {
for (int i=0; i<18; i++) {
sectionSizes[i] = -1;
sectionOffsets[i] = -1;
}
}
/**
* Gets the offsetted item of the specified type for the given offset. This method does not support retrieving an
* optional item where a value of 0 indicates "not present". Use getOptionalOffsettedItemByOffset instead.
*
* @param itemType The type of item to get
* @param offset The offset of the item
* @return the offsetted item of the specified type at the specified offset
*/
public Item getOffsettedItemByOffset(ItemType itemType, int offset) {
assert !itemType.isIndexedItem();
SparseArray<Item> sa = itemsByType[itemType.SectionIndex];
Item item = sa.get(offset);
if (item == null) {
throw new ExceptionWithContext(String.format("Could not find the %s item at offset %#x",
itemType.TypeName, offset));
}
return item;
}
/**
* Gets the optional offsetted item of the specified type for the given offset
*
* @param itemType The type of item to get
* @param offset The offset of the item
* @return the offsetted item of the specified type at the specified offset, or null if the offset is 0
*/
public Item getOptionalOffsettedItemByOffset(ItemType itemType, int offset) {
assert !itemType.isIndexedItem();
assert !itemType.isIndexedItem();
SparseArray<Item> sa = itemsByType[itemType.SectionIndex];
Item item = sa.get(offset);
if (item == null && offset != 0) {
throw new ExceptionWithContext(String.format("Could not find the %s item at offset %#x",
itemType.TypeName, offset));
}
return item;
}
/**
* Adds the size and offset information for the given offset
* @param itemType the item type of the section
* @param sectionSize the size of the section
* @param sectionOffset the offset of the section
*/
public void addSection(final ItemType itemType, int sectionSize, int sectionOffset) {
int storedSectionSize = sectionSizes[itemType.SectionIndex];
if (storedSectionSize == -1) {
sectionSizes[itemType.SectionIndex] = sectionSize;
} else {
if (storedSectionSize != sectionSize) {
throw new RuntimeException("The section size in the header and map for item type "
+ itemType + " do not match");
}
}
int storedSectionOffset = sectionOffsets[itemType.SectionIndex];
if (storedSectionOffset == -1) {
sectionOffsets[itemType.SectionIndex] = sectionOffset;
} else {
if (storedSectionOffset != sectionOffset) {
throw new RuntimeException("The section offset in the header and map for item type "
+ itemType + " do not match");
}
}
}
/**
* Sets the items for the specified section. This should be called by an offsetted section
* after it is finished reading in all its items.
* @param itemType the item type of the section. This must be an offsetted item type
* @param items the full list of items in the section, ordered by offset
*/
public void setItemsForSection(ItemType itemType, List<? extends Item> items) {
assert !itemType.isIndexedItem();
SparseArray<Item> sa = itemsByType[itemType.SectionIndex];
sa.ensureCapacity(items.size());
for (Item item: items) {
sa.append(item.getOffset(), item);
}
}
/**
* @param itemType the item type of the section
* @return the size of the given section as it was read in from the map item
*/
public int getSectionSize(ItemType itemType) {
return sectionSizes[itemType.SectionIndex];
}
/**
* @param itemType the item type of the section
* @return the offset of the given section as it was read in from the map item
*/
public int getSectionOffset(ItemType itemType) {
return sectionOffsets[itemType.SectionIndex];
}
}