Fixed sizing logic error in ensureSpaceFor()

lib/redis-client.js

@@ -691,7 +691,7 @@ Client.prototype.sendCommand = function () {
         // If we know how much space we need, use that + 10%.
         // Else double the size of the buffer.
 
-        var bufferLength = Math.max(currentLength * 2, atLeast * 1.1);
+        var bufferLength = Math.max(currentLength * 2, offset + atLeast * 1.1);
         var newBuffer = new Buffer(Math.round(bufferLength));
         self.requestBuffer.copy(newBuffer, 0, 0, offset); // target, targetStart, srcStart, srcEnd
         self.requestBuffer = newBuffer;
@@ -708,14 +708,14 @@ Client.prototype.sendCommand = function () {
     for (var i=1; i < argCount; ++i) {
         var arg = arguments[i];
         if (arg instanceof Buffer) {
-            ensureSpaceFor(arg.length + arg.length.toString().length + extrasLength + offset);
+            ensureSpaceFor(arg.length + arg.length.toString().length + extrasLength);
             offset += this.requestBuffer.asciiWrite('$' + arg.length + CRLF, offset);
             offset += arg.copy(this.requestBuffer, offset, 0);  // target, targetStart, srcStart
             offset += this.requestBuffer.asciiWrite(CRLF, offset);
         } else if (arg.toString) {
             var asString = arg.toString();
             var serialized = '$' + Buffer.byteLength(asString, "binary") + CRLF + asString + CRLF;
-            ensureSpaceFor(Buffer.byteLength(serialized, "binary") + offset);
+            ensureSpaceFor(Buffer.byteLength(serialized, "binary"));
             offset += this.requestBuffer.binaryWrite(serialized, offset);
         }
     }