Ninja not found by CMake
<p>I'm trying to build some code I got from GitHub using CMake, but keep getting the followings errors:</p>

<pre><code>CMake Error: CMake was unable to find a build program corresponding to "Ninja".  CMAKE_MAKE_PROGRAM is not set.  You probably need to select a different build tool.
CMake Error: Error required internal CMake variable not set, cmake may be not be built correctly.
Missing variable is:
CMAKE_C_COMPILER_ENV_VAR
CMake Error: Error required internal CMake variable not set, cmake may be not be built correctly.
Missing variable is:
CMAKE_C_COMPILER
CMake Error: Could not find cmake module file:/golang/project/src/github.com/devsisters/goquic/libquic/build/debug/CMakeFiles/2.8.11/CMakeCCompiler.cmake
CMake Error: Error required internal CMake variable not set, cmake may be not be built correctly.
Missing variable is:
CMAKE_CXX_COMPILER_ENV_VAR
CMake Error: Error required internal CMake variable not set, cmake may be not be built correctly.
Missing variable is:
CMAKE_CXX_COMPILER
CMake Error: Could not find cmake module file:/golang/project/src/github.com/devsisters/goquic/libquic/build/debug/CMakeFiles/2.8.11/CMakeCXXCompiler.cmake
-- Configuring incomplete, errors occurred!
</code></pre>

<p>How do I set these variables correctly?</p>

<p>I used a <code>./build_libs.sh</code> file that came with the GitHub code to build this.</p>