Merge pull request #37 from RUB-NDS/numberConverterFixes

intToBytes and longToBytes had errors when working with arrays larger…

Author: ic0ns

src/main/java/de/rub/nds/modifiablevariable/util/ArrayConverter.java

@@ -72,7 +72,8 @@ public static byte[] intToBytes(int value, int size) {
         }
         byte[] result = new byte[size];
         int shift = 0;
-        for (int i = size - 1; i >= 0; i--) {
+        int finalPosition = ((size > Integer.BYTES) ? (size - Integer.BYTES) : 0);
+        for (int i = size - 1; i >= finalPosition; i--) {
             result[i] = (byte) (value >>> shift);
             shift += 8;
         }
@@ -96,7 +97,8 @@ public static byte[] longToBytes(long value, int size) {
         }
         byte[] result = new byte[size];
         int shift = 0;
-        for (int i = size - 1; i >= 0; i--) {
+        int finalPosition = ((size > Long.BYTES) ? (size - Long.BYTES) : 0);
+        for (int i = size - 1; i >= finalPosition; i--) {
             result[i] = (byte) (value >>> shift);
             shift += 8;
         }

src/test/java/de/rub/nds/modifiablevariable/util/ArrayConverterTest.java

@@ -44,6 +44,34 @@ public void testIntToBytes() {
         assertArrayEquals("The conversion result of 5717 should be {0x16} {0x55}", new byte[] { 0x16, 0x55 }, result);
     }
 
+    @Test
+    public void testIntToBytesOverflow() {
+        int toParse = 5717;
+        byte[] result = ArrayConverter.intToBytes(toParse, 5);
+        assertArrayEquals("The conversion result of 5717 should be {0x00} {0x00} {0x00} {0x16} {0x55}", new byte[] {
+                0x00, 0x00, 0x00, 0x16, 0x55 }, result);
+    }
+
+    /**
+     * Test of intToBytes method, of class ArrayConverter.
+     */
+    @Test
+    public void testLongToBytes() {
+        long toParse = 5717;
+        byte[] result = ArrayConverter.longToBytes(toParse, 2);
+        assertArrayEquals("The conversion result of 5717 should be {0x16} {0x55}", new byte[] { 0x16, 0x55 }, result);
+    }
+
+    @Test
+    public void testLongToBytesOverflow() {
+        int toParse = 5717;
+        byte[] result = ArrayConverter.longToBytes(toParse, 10);
+        assertArrayEquals(
+                "The conversion result of 5717 should be {0x00} {0x00} {0x00} {0x00} {0x00} {0x00} {0x00} {0x00} "
+                        + "{0x16} {0x55}", new byte[] { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x16, 0x55 },
+                result);
+    }
+
     /**
      * Test of bytesToInt method, of class ArrayConverter.
      */