From 4080fe659d63703974560020c549dc26da5a2f49 Mon Sep 17 00:00:00 2001
From: "JesusFreke@JesusFreke.com"
 <JesusFreke@JesusFreke.com@55b6fa8a-2a1e-11de-a435-ffa8d773f76a>
Date: Sun, 13 Sep 2009 19:57:25 +0000
Subject: [PATCH] Improve handling of the dex and odex magic values

git-svn-id: https://smali.googlecode.com/svn/trunk@469 55b6fa8a-2a1e-11de-a435-ffa8d773f76a
---
 .../src/main/java/org/jf/dexlib/DexFile.java  |  9 +++----
 .../main/java/org/jf/dexlib/HeaderItem.java   | 24 +++++++------------
 .../java/org/jf/dexlib/OdexHeaderItem.java    | 11 ++-------
 3 files changed, 13 insertions(+), 31 deletions(-)

diff --git a/dexlib/src/main/java/org/jf/dexlib/DexFile.java b/dexlib/src/main/java/org/jf/dexlib/DexFile.java
index 642be598..bd9731b0 100644
--- a/dexlib/src/main/java/org/jf/dexlib/DexFile.java
+++ b/dexlib/src/main/java/org/jf/dexlib/DexFile.java
@@ -277,12 +277,8 @@ public class DexFile
         byte[] magic = FileUtils.readFile(file, 0, 8);
         byte[] dexMagic, odexMagic;
 
-        try {
-            dexMagic = HeaderItem.MAGIC.getBytes("US-ASCII");
-            odexMagic = OdexHeaderItem.MAGIC.getBytes("US-ASCII");
-        } catch (UnsupportedEncodingException ex) {
-            throw new RuntimeException(ex);
-        }
+        dexMagic = HeaderItem.MAGIC;
+        odexMagic = OdexHeaderItem.MAGIC;
 
         boolean isDex = true;
         this.isOdex = true;
@@ -306,6 +302,7 @@ public class DexFile
         } else if (isDex) {
             in = new ByteArrayInput(FileUtils.readFile(file));
         } else {
+            
             StringBuilder sb = new StringBuilder();
             sb.append("bad magic value:");
             for (int i=0; i<8; i++) {
diff --git a/dexlib/src/main/java/org/jf/dexlib/HeaderItem.java b/dexlib/src/main/java/org/jf/dexlib/HeaderItem.java
index 31e2a1a1..9d30f0ba 100644
--- a/dexlib/src/main/java/org/jf/dexlib/HeaderItem.java
+++ b/dexlib/src/main/java/org/jf/dexlib/HeaderItem.java
@@ -39,7 +39,8 @@ public class HeaderItem extends Item<HeaderItem> {
      * the file format magic number, represented as the
      * low-order bytes of a string
      */
-    public static final String MAGIC = "dex\n035" + '\0';
+    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;
@@ -58,17 +59,10 @@ public class HeaderItem extends Item<HeaderItem> {
 
     /** {@inheritDoc} */
     protected void readItem(Input in, ReadContext readContext) {
-        byte[] expectedMagic;
-        try {
-            expectedMagic = MAGIC.getBytes("US-ASCII");
-        } catch (UnsupportedEncodingException ex) {
-            throw new RuntimeException(ex);
-        }
-        
         byte[] readMagic = in.readBytes(8);
 
         for (int i=0; i<8; i++) {
-            if (expectedMagic[i] != readMagic[i]) {
+            if (MAGIC[i] != readMagic[i]) {
                 throw new RuntimeException("The magic value is not the expected value");
             }
         }
@@ -145,15 +139,13 @@ public class HeaderItem extends Item<HeaderItem> {
 
     /** {@inheritDoc} */
     protected void writeItem(AnnotatedOutput out) {
-        byte[] magic;
-        try {
-            magic = MAGIC.getBytes("US-ASCII");
-        } catch (UnsupportedEncodingException ex) {
-            throw new RuntimeException(ex);
+        StringBuilder magicBuilder = new StringBuilder();
+        for (int i=0; i<8; i++) {
+            magicBuilder.append((char)MAGIC[i]);
         }
 
-        out.annotate("magic: " + Utf8Utils.escapeString(MAGIC));
-        out.write(magic);
+        out.annotate("magic: " + Utf8Utils.escapeString(magicBuilder.toString()));
+        out.write(MAGIC);
 
         out.annotate("checksum");
         out.writeInt(0);
diff --git a/dexlib/src/main/java/org/jf/dexlib/OdexHeaderItem.java b/dexlib/src/main/java/org/jf/dexlib/OdexHeaderItem.java
index 19592a4f..b20a8ec5 100644
--- a/dexlib/src/main/java/org/jf/dexlib/OdexHeaderItem.java
+++ b/dexlib/src/main/java/org/jf/dexlib/OdexHeaderItem.java
@@ -38,7 +38,7 @@ public class OdexHeaderItem {
      * the file format magic number, represented as the
      * low-order bytes of a string
      */
-    public static final String MAGIC = "dey\n035" + '\0';
+    public static final byte[] MAGIC = new byte[] {0x64, 0x65, 0x79, 0x0A, 0x30, 0x33, 0x35, 0x00};//"dey\n035" + '\0';
 
     public final byte[] magic;
     public final int dexOffset;
@@ -52,15 +52,8 @@ public class OdexHeaderItem {
     public OdexHeaderItem(Input in) {
         magic = in.readBytes(8);
 
-        byte[] expectedMagic;
-        try {
-            expectedMagic = MAGIC.getBytes("US-ASCII");
-        } catch (UnsupportedEncodingException ex) {
-            throw new RuntimeException(ex);
-        }
-
         for (int i=0; i<8; i++) {
-            if (expectedMagic[i] != magic[i]) {
+            if (MAGIC[i] != magic[i]) {
                 throw new RuntimeException("The magic value is not the expected value");
             }
         }