There are no "nice" functions with such properties. Every solution is discontinuesdiscontinuous at a dense subset of $\mathbb{R}$. Just look on poles of $\tan x$. Let $x=\pi/2+\pi m$, $m\in\mathbb{Z}$. Clearly either $T$ is discontinuesdiscontinuous at $x$ or at $x+1$. In the latter case it is also discontinuesdiscontinuous at $x+k$ for every positive integer $k$. In the former case, $T$ is discontinuesdiscontinuous at $x+k$ for every non-positive integer $k$.