add install target and libm dependency

CMakeLists.txt

@@ -1,11 +1,9 @@
 cmake_minimum_required(VERSION 3.1)
-project(rnnoise)
+include(CheckLibraryExists)
 
-option(RNNOISE_COMPILE_OPUS ON)
+project(rnnoise LANGUAGES C)
 
-if(RNNOISE_COMPILE_OPUS)
-	add_definitions(-DCOMPILE_OPUS)
-endif()
+add_definitions(-DCOMPILE_OPUS)
 
 # Ignore CRT warnings
 add_definitions(-D_CRT_SECURE_NO_WARNINGS)
@@ -36,4 +34,35 @@ endif()
 target_include_directories(rnnoise PUBLIC
         $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
         $<INSTALL_INTERFACE:include>
-        PRIVATE src)
+        PRIVATE src)
+
+# dependencies
+if(NOT WIN32)
+	check_library_exists(m cos "" HAVE_LIBM)
+	if(HAVE_LIBM)
+		#find_library(LIBM m)
+		set(LIBM m)
+	endif()
+endif()
+if(HAVE_LIBM)
+	if(BUILD_SHARED_LIBS)
+		target_link_libraries(rnnoise PRIVATE ${LIBM})
+	else()
+		target_link_libraries(rnnoise PUBLIC ${LIBM})
+	endif()
+endif()
+
+install(TARGETS rnnoise
+	EXPORT ${CMAKE_PROJECT_NAME}Config
+	LIBRARY DESTINATION lib COMPONENT lib
+	ARCHIVE DESTINATION lib COMPONENT lib
+	RUNTIME DESTINATION bin COMPONENT bin)
+
+install(DIRECTORY "include"
+	DESTINATION . COMPONENT dev
+	FILES_MATCHING
+	PATTERN "*.h")
+
+install(EXPORT ${CMAKE_PROJECT_NAME}Config
+	DESTINATION cmake)
+

src/kiss_fft.c

@@ -600,4 +600,4 @@ void opus_ifft_c(const kiss_fft_state *st,const kiss_fft_cpx *fin,kiss_fft_cpx *
    for (i=0;i<st->nfft;i++)
       fout[i].i = -fout[i].i;
 }
-#endif
+#endif