From da9cf2d8c9a49e3bf353dde0607d056d3c6c7b5d Mon Sep 17 00:00:00 2001
From: "Taro L. Saito" <leo@xerial.org>
Date: Sat, 4 Jun 2011 11:36:52 +0900
Subject: [PATCH] Add a pure-java code for GetUncompressedLength()

---
 src/main/java/org/xerial/snappy/Snappy.java   |  59 ++++++++++++++++++
 .../native/Windows/amd64/snappyjava.dll       | Bin 644608 -> 644608 bytes
 .../snappy/native/Windows/x86/snappyjava.dll  | Bin 598528 -> 598528 bytes
 3 files changed, 59 insertions(+)

diff --git a/src/main/java/org/xerial/snappy/Snappy.java b/src/main/java/org/xerial/snappy/Snappy.java
index ea6b41e..256a5b4 100755
--- a/src/main/java/org/xerial/snappy/Snappy.java
+++ b/src/main/java/org/xerial/snappy/Snappy.java
@@ -384,9 +384,68 @@ public class Snappy
     public static int uncompressedLength(byte[] input, int offset, int length) throws SnappyException {
         if (input == null)
             throw new NullPointerException("input is null");
+
         return SnappyNative.uncompressedLength(input, offset, length);
     }
 
+    public static class CompressedDataLength
+    {
+        public final int cursor;
+        public final int uncompressedLength;
+
+        public CompressedDataLength(int cursor, int uncompressedLength) {
+            this.cursor = cursor;
+            this.uncompressedLength = uncompressedLength;
+        }
+    }
+
+    public static CompressedDataLength getUncompressedLength(byte[] input, int offset, int limit)
+            throws SnappyException {
+        if (input == null)
+            throw new NullPointerException("input is null");
+
+        long b = 0;
+        long result = 0;
+        int cursor = offset;
+        if (cursor >= limit)
+            return null;
+        for (;;) {
+            b = input[cursor++];
+            result = b & 127;
+            if (b < 128)
+                break;
+            if (cursor >= limit)
+                return null;
+            b = input[cursor++];
+            result |= (b & 127) << 7;
+            if (b < 128)
+                break;
+            if (cursor >= limit)
+                return null;
+            b = input[cursor++];
+            result |= (b & 127) << 14;
+            if (b < 128)
+                break;
+            if (cursor >= limit)
+                return null;
+            b = input[cursor++];
+            result |= (b & 127) << 21;
+            if (b < 128)
+                break;
+            if (cursor >= limit)
+                return null;
+            b = input[cursor++];
+            result |= (b & 127) << 28;
+            if (b < 16)
+                break;
+            return null; // Value is too long to be a varint32
+        }
+        if (result > Integer.MAX_VALUE)
+            throw new IllegalStateException("cannot uncompress byte array longer than 2^31-1: " + result);
+
+        return new CompressedDataLength(cursor, (int) result);
+    }
+
     /**
      * Get the uncompressed byte size of the given compressed input. This
      * operation taks O(1) time.
diff --git a/src/main/resources/org/xerial/snappy/native/Windows/amd64/snappyjava.dll b/src/main/resources/org/xerial/snappy/native/Windows/amd64/snappyjava.dll
index c4da58e2139b75baf38175ba8211f4a6a07540f0..ab4dad2c99fcb360d5ad3b4ffa311f271efa624f 100755
GIT binary patch
delta 59
zcmV-B0L1@*tS5l1Cy<B(hLh=$i%kOk>w(&Z+5v^y0)^TGh1vv#+69H$28G%Oh1v+U
R+6gMJ1BH|6w+FBZ`6X(n9GCzA

delta 59
zcmV-B0L1@*tS5l1Cy<B(B%0`vi%kMI`GMMn+5v^y0)^TGh1vv#+69H$28G%Oh1v+U
R+6gMJ10$N~w+FBZ`6V`U8z=w(

diff --git a/src/main/resources/org/xerial/snappy/native/Windows/x86/snappyjava.dll b/src/main/resources/org/xerial/snappy/native/Windows/x86/snappyjava.dll
index 7a0a7b4b6ea0bb18f5885f4e54ad4b69e3e86b8d..8a87909566125569c0a8ee837caefea07d26865d 100755
GIT binary patch
delta 55
zcmZoTqSA0gWkLtD+^m-qyL}n|H{NW$$=G_6sr4pv>rIx{o2;!j*;;S1Z@tN(y&t4#
KJNp5SpNRn80vZAU

delta 55
zcmZoTqSA0gWkLrt>#P?OyL}l?H{NW$$=G_6sr4pv>rIx{o2;!j*;;S1Z@tN(y&t4#
KJNp5SpNRm_gc+Iu