Fixed a few buffer overrun bugs due to having assumed a "char" was just 1 byte (it is 2 bytes in .NET), and fixed a loop index bug that caused GetStringAscii to return a string that was just the first character repeated multiple times.

Author: strangelydim

src/Adaptive.Agrona/Concurrent/UnsafeBuffer.cs

@@ -828,7 +828,7 @@ public int GetStringAscii(int index, int length, StringBuilder appendable)
         {
             for (int i = index + BitUtil.SIZE_OF_INT, limit = index + BitUtil.SIZE_OF_INT + length; i < limit; i++)
             {
-                char c = *(char*)(_pBuffer + index);
+                char c = (char)*(_pBuffer + i);
                 appendable.Append(c > (char)127 ? '?' : c);
             }
 
@@ -879,7 +879,7 @@ public int PutStringWithoutLengthAscii(int index, string value)
                     c = '?';
                 }
 
-                *(char*)(_pBuffer + index + i) = c;
+                *(_pBuffer + index + i) = (byte)c;
             }
 
             return length;
@@ -899,7 +899,7 @@ public int PutStringWithoutLengthAscii(int index, string value, int valueOffset,
                     c = '?';
                 }
 
-                *(char*)(_pBuffer + index + i) = c;
+                *(_pBuffer + index + i) = (byte)c;
             }
 
             return len;

src/Adaptive.Agrona/ExpandableArrayBuffer.cs

@@ -258,7 +258,7 @@ public int GetStringAscii(int index, int length, StringBuilder appendable)
         {
             for (int i = index + BitUtil.SIZE_OF_INT, limit = index + BitUtil.SIZE_OF_INT + length; i < limit; i++)
             {
-                char c = *(char*)(_pBuffer + index);
+                char c = (char)*(_pBuffer + i);
                 appendable.Append(c > (char)127 ? '?' : c);
             }
 
@@ -472,7 +472,7 @@ public int PutStringWithoutLengthAscii(int index, string value)
                     c = '?';
                 }
 
-                *(char*)(_pBuffer + index + i) = c;
+                *(_pBuffer + index + i) = (byte)c;
             }
 
             return length;
@@ -493,7 +493,7 @@ public int PutStringWithoutLengthAscii(int index, string value, int valueOffset,
                     c = '?';
                 }
 
-                *(char*)(_pBuffer + index + i) = c;
+                *(_pBuffer + index + i) = (byte)c;
             }
 
             return len;