DRILL-1353: Fix decimal regressions

3 files changed, 52 insertions, 8 deletions

diff --git a/exec/java-exec/src/main/codegen/templates/Decimal/CastDecimalSimilar.java b/exec/java-exec/src/main/codegen/templates/Decimal/CastDecimalSimilar.java
index 8c46b4959..cd2c39090 100644
--- a/exec/java-exec/src/main/codegen/templates/Decimal/CastDecimalSimilar.java
+++ b/exec/java-exec/src/main/codegen/templates/Decimal/CastDecimalSimilar.java
@@ -83,7 +83,7 @@ public class Cast${type.from}${type.to} implements DrillSimpleFunc{
         if (in.scale != out.scale) {
           org.apache.drill.exec.util.DecimalUtility.roundDecimal(out.buffer, out.start, out.nDecimalDigits, out.scale, in.scale);
         }
-        out.setSign(sign, in.start, in.buffer);
+        out.setSign(sign, out.start, out.buffer);
     }
 }
 </#if> <#-- type.major -->
diff --git a/exec/java-exec/src/main/java/org/apache/drill/exec/expr/fn/impl/ByteFunctionHelpers.java b/exec/java-exec/src/main/java/org/apache/drill/exec/expr/fn/impl/ByteFunctionHelpers.java
index b5241395e..cbb87bbae 100644
--- a/exec/java-exec/src/main/java/org/apache/drill/exec/expr/fn/impl/ByteFunctionHelpers.java
+++ b/exec/java-exec/src/main/java/org/apache/drill/exec/expr/fn/impl/ByteFunctionHelpers.java
@@ -26,6 +26,17 @@ import org.apache.drill.exec.util.DecimalUtility;
 public class ByteFunctionHelpers {
   static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(ByteFunctionHelpers.class);
 
+  /**
+   * Helper function to check for equality of bytes in two DrillBuffers
+   *
+   * @param laddr start address of the DrillBuf
+   * @param lStart start offset in the buffer
+   * @param lEnd end offset in the buffer
+   * @param raddr start address of the DrillBuf
+   * @param rStart start offset in the buffer
+   * @param rEnd end offset in the buffer
+   * @return 1 if left input is greater, -1 if left input is smaller, 0 otherwise
+   */
   public static final int equal(final long laddr, int lStart, int lEnd, final long raddr, int rStart,
       final int rEnd) {
 
@@ -59,6 +70,17 @@ public class ByteFunctionHelpers {
     }
   }
 
+  /**
+   * Helper function to compare a set of bytes in two DrillBuffers
+   *
+   * @param laddr start address of the DrillBuf
+   * @param lStart start offset in the buffer
+   * @param lEnd end offset in the buffer
+   * @param raddr start address of the DrillBuf
+   * @param rStart start offset in the buffer
+   * @param rEnd end offset in the buffer
+   * @return 1 if left input is greater, -1 if left input is smaller, 0 otherwise
+   */
   public static final int compare(final long laddr, int lStart, int lEnd, final long raddr, int rStart, final int rEnd) {
     int lLen = lEnd - lStart;
     int rLen = rEnd - rStart;
@@ -93,6 +115,17 @@ public class ByteFunctionHelpers {
 
   }
 
+  /**
+   * Helper function to compare a set of bytes in DrillBuf to a ByteArray.
+   *
+   * @param laddr start address of the DrillBuf
+   * @param lStart start offset in the buffer
+   * @param lEnd end offset in the buffer
+   * @param right second input to be compared
+   * @param rStart start offset in the byte array
+   * @param rEnd end offset in the byte array
+   * @return 1 if left input is greater, -1 if left input is smaller, 0 otherwise
+   */
   public static final int compare(final long laddr, int lStart, int lEnd, final byte[] right, int rStart, final int rEnd) {
     int lLen = lEnd - lStart;
     int rLen = rEnd - rStart;
@@ -117,11 +150,20 @@ public class ByteFunctionHelpers {
     return lLen > rLen ? 1 : -1;
 
   }
-  // Get the big endian integer
+
+  /*
+   * Following are helper functions to interact with sparse decimal represented in a byte array.
+   */
+
+  // Get the integer ignore the sign
   public static int getInteger(byte[] b, int index) {
+    return getInteger(b, index, true);
+  }
+  // Get the integer, ignore the sign
+  public static int getInteger(byte[] b, int index, boolean ignoreSign) {
     int startIndex = index * DecimalUtility.integerSize;
 
-    if (index == 0) {
+    if (index == 0 && ignoreSign == true) {
       return (b[startIndex + 3] & 0xFF) |
              (b[startIndex + 2] & 0xFF) << 8 |
              (b[startIndex + 1] & 0xFF) << 16 |
@@ -133,9 +175,9 @@ public class ByteFunctionHelpers {
         (b[startIndex + 1] & 0xFF) << 16 |
         (b[startIndex] & 0xFF) << 24);
 
-    }
+  }
 
-  // Set the big endian bytes for the input integer
+  // Set integer in the byte array
   public static void setInteger(byte[] b, int index, int value) {
     int startIndex = index * DecimalUtility.integerSize;
     b[startIndex] = (byte) ((value >> 24) & 0xFF);
@@ -156,6 +198,6 @@ public class ByteFunctionHelpers {
 
   // Get the sign
   public static boolean getSign(byte[] b) {
-    return ((b[0] & 0x80) > 0);
+    return ((getInteger(b, 0, false) & 0x80000000) != 0);
   }
 }
diff --git a/exec/java-exec/src/main/java/org/apache/drill/exec/expr/fn/impl/DrillByteArray.java b/exec/java-exec/src/main/java/org/apache/drill/exec/expr/fn/impl/DrillByteArray.java
index 507db6746..d1c67ef5d 100644
--- a/exec/java-exec/src/main/java/org/apache/drill/exec/expr/fn/impl/DrillByteArray.java
+++ b/exec/java-exec/src/main/java/org/apache/drill/exec/expr/fn/impl/DrillByteArray.java
@@ -17,8 +17,10 @@
  */
 package org.apache.drill.exec.expr.fn.impl;
 
-import io.netty.buffer.ByteBuf;
-
+/**
+ * Thin wrapper around byte array. This class is used by aggregate functions which
+ * consume decimal, variable width vectors as inputs. 
+ */
 public class DrillByteArray {
   private byte[] bytes;
   private int length;