add support for extraction of IMPLODED flagged blocks

inwc3 · Jul 15, 2018 · 51231ce · 51231ce
1 parent d7402d8
commit 51231ce
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Showing 3 changed files with 79 additions and 11 deletions.
diff --git a/src/main/java/systems/crigges/jmpq3/MpqFile.java b/src/main/java/systems/crigges/jmpq3/MpqFile.java
@@ -20,6 +20,7 @@ public class MpqFile {
     public static final int ADJUSTED_ENCRYPTED = 0x00020000;
     public static final int EXISTS = 0x80000000;
     public static final int DELETED = 0x02000000;
+    public static final int IMPLODED = 0x00000100;
 
     private ByteBuffer buf;
     private Block block;
@@ -83,6 +84,52 @@ public void extractToOutputStream(OutputStream writer) throws IOException {
             writer.close();
             return;
         }
+        if (extractImplodedBlock(writer)) return;
+        if (extractSingleUnitBlock(writer)) return;
+        if (block.hasFlag(COMPRESSED)) {
+            extractCompressedBlock(writer);
+        } else {
+            check(writer);
+        }
+    }
+
+    private void extractCompressedBlock(OutputStream writer) throws IOException {
+        buf.position(0);
+        byte[] sot = new byte[sectorCount * 4];
+        buf.get(sot);
+        if (isEncrypted) {
+            new MPQEncryption(baseKey - 1, true).processSingle(ByteBuffer.wrap(sot));
+        }
+        ByteBuffer sotBuffer = ByteBuffer.wrap(sot).order(ByteOrder.LITTLE_ENDIAN);
+        int start = sotBuffer.getInt();
+        int end = sotBuffer.getInt();
+        int finalSize = 0;
+        for (int i = 0; i < sectorCount - 1; i++) {
+            buf.position(0 + start);
+            byte[] arr = getSectorAsByteArray(buf, end - start);
+            if (isEncrypted) {
+                new MPQEncryption(baseKey + i, true).processSingle(ByteBuffer.wrap(arr));
+            }
+            if (block.getNormalSize() - finalSize <= sectorSize) {
+                arr = decompressSector(arr, end - start, block.getNormalSize() - finalSize);
+            } else {
+                arr = decompressSector(arr, end - start, sectorSize);
+            }
+            writer.write(arr);
+
+            finalSize += sectorSize;
+            start = end;
+            try {
+                end = sotBuffer.getInt();
+            } catch (BufferUnderflowException e) {
+                break;
+            }
+        }
+        writer.flush();
+        writer.close();
+    }
+
+    private boolean extractSingleUnitBlock(OutputStream writer) throws IOException {
         if (block.hasFlag(SINGLE_UNIT)) {
             if (block.hasFlag(COMPRESSED)) {
                 buf.position(0);
@@ -97,17 +144,20 @@ public void extractToOutputStream(OutputStream writer) throws IOException {
             } else {
                 check(writer);
             }
-            return;
+            return true;
         }
-        if (block.hasFlag(COMPRESSED)) {
-            ByteBuffer sotBuffer = null;
+        return false;
+    }
+
+    private boolean extractImplodedBlock(OutputStream writer) throws IOException {
+        if (block.hasFlag(IMPLODED)) {
             buf.position(0);
             byte[] sot = new byte[sectorCount * 4];
             buf.get(sot);
             if (isEncrypted) {
                 new MPQEncryption(baseKey - 1, true).processSingle(ByteBuffer.wrap(sot));
             }
-            sotBuffer = ByteBuffer.wrap(sot).order(ByteOrder.LITTLE_ENDIAN);
+            ByteBuffer sotBuffer = ByteBuffer.wrap(sot).order(ByteOrder.LITTLE_ENDIAN);
             int start = sotBuffer.getInt();
             int end = sotBuffer.getInt();
             int finalSize = 0;
@@ -118,9 +168,9 @@ public void extractToOutputStream(OutputStream writer) throws IOException {
                     new MPQEncryption(baseKey + i, true).processSingle(ByteBuffer.wrap(arr));
                 }
                 if (block.getNormalSize() - finalSize <= sectorSize) {
-                    arr = decompressSector(arr, end - start, block.getNormalSize() - finalSize);
+                    arr = decompressImplodedSector(arr, end - start, block.getNormalSize() - finalSize);
                 } else {
-                    arr = decompressSector(arr, end - start, sectorSize);
+                    arr = decompressImplodedSector(arr, end - start, sectorSize);
                 }
                 writer.write(arr);
 
@@ -134,9 +184,9 @@ public void extractToOutputStream(OutputStream writer) throws IOException {
             }
             writer.flush();
             writer.close();
-        } else {
-            check(writer);
+            return true;
         }
+        return false;
     }
 
     private void check(OutputStream writer) throws IOException {
@@ -348,6 +398,10 @@ private byte[] decompressSector(byte[] sector, int normalSize, int uncompressedS
         return CompressionUtil.decompress(sector, normalSize, uncompressedSize);
     }
 
+    private byte[] decompressImplodedSector(byte[] sector, int normalSize, int uncompressedSize) throws JMpqException {
+        return CompressionUtil.explode(sector, normalSize, uncompressedSize);
+    }
+
     @Override
     public String toString() {
         return "MpqFile [sectorSize=" + sectorSize + ", compressedSize=" + compressedSize + ", normalSize=" + normalSize + ", flags=" + flags + ", name=" + name

diff --git a/src/main/java/systems/crigges/jmpq3/compression/CompressionUtil.java b/src/main/java/systems/crigges/jmpq3/compression/CompressionUtil.java
@@ -56,7 +56,7 @@ public static byte[] decompress(byte[] sector, int compressedSize, int uncompres
                 throw new JMpqException("Unsupported compression Bzip2");
             } else if (isImploded) {
                 byte[] output = new byte[uncompressedSize];
-                Exploder.pkexplode(sector, output);
+                Exploder.pkexplode(sector, output, 1);
                 out.put(output);
                 out.position(0);
                 flip = !flip;
@@ -97,4 +97,18 @@ public static byte[] decompress(byte[] sector, int compressedSize, int uncompres
             return (flip ? out : in).array();
         }
     }
+
+    public static byte[] explode(byte[] sector, int compressedSize, int uncompressedSize) throws JMpqException {
+        if (compressedSize == uncompressedSize) {
+            return sector;
+        } else {
+            ByteBuffer out = ByteBuffer.wrap(new byte[uncompressedSize]);
+
+            byte[] output = new byte[uncompressedSize];
+            Exploder.pkexplode(sector, output, 0);
+            out.put(output);
+            out.position(0);
+            return out.array();
+        }
+    }
 }
diff --git a/src/main/java/systems/crigges/jmpq3/compression/Exploder.java b/src/main/java/systems/crigges/jmpq3/compression/Exploder.java
@@ -150,15 +150,15 @@ private static long TRUNCATE_VALUE(long value, int bits)  {
                     0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08
             };
 
-    public static int pkexplode(byte[] pInBuffer, byte[] pOutBuffer) {
+    public static int pkexplode(byte[] pInBuffer, byte[] pOutBuffer, int inPos) {
         // Compressed data cannot be less than 4 bytes;
         // this is not possible in any case whatsoever
         if (pInBuffer.length < 4)
             throw new IllegalArgumentException("PK_ERR_INCOMPLETE_INPUT: Incomplete input");
 
         int pOutPos = 0;
         // This is 1 because in an mpq-sector, the first byte is the compression type flag
-        int pInPos = 1;
+        int pInPos = inPos;
 
         // Get header from compressed data
         byte nLitSize = pInBuffer[pInPos++];