Enhancements

Fix dependency bug for compiling on some platforms.
Add specifying port via environment variable.
Add BacktoCN.list extracted from ConnersHua's original BakctoCN configuration.

CMakeLists.txt

@@ -10,9 +10,21 @@ ADD_DEFINITIONS(-Wall -Wextra -Wno-unused-parameter -Wno-unused-result)
 OPTION(USING_STD_REGEX "Use std::regex from C++ library instead of PCRECPP." OFF)
 OPTION(USING_MALLOC_TRIM "Call malloc_trim after processing request to lower memory usage (Your system must support malloc_trim)." OFF)
 
-IF(MACOS)
+INCLUDE(CheckCXXSourceCompiles)
+CHECK_CXX_SOURCE_COMPILES(
+"
+#include<string>
+int main(){std::to_string(0);return 0;}
+" HAVE_TO_STRING)
+
+IF(APPLE)
 	ADD_DEFINITIONS(-D_MACOS)
 ENDIF()
+
+IF(HAVE_TO_STRING)
+	ADD_DEFINITIONS(-DHAVE_TO_STRING)
+ENDIF()
+
 IF(USING_MALLOC_TRIM)
 	ADD_DEFINITIONS(-DMALLOC_TRIM)
 ENDIF()