From 5c708d85dbddbf7dc92f34fb1eda0c8eb10ce9a1 Mon Sep 17 00:00:00 2001
From: Anonymous Maarten <anonymous.maarten@gmail.com>
Date: Thu, 29 Oct 2020 21:36:08 +0100
Subject: [PATCH] Add cmake install + MSVC dll support

---
 CMakeLists.txt | 22 ++++++++++++++++++++++
 kiss_fft.h     | 25 ++++++++++++++++++++-----
 2 files changed, 42 insertions(+), 5 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7667d0f..6a09110 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -3,7 +3,29 @@ project(kissfft)
 
 add_library(kissfft
   kiss_fft.c)
+add_library(kissfft::kissfft ALIAS kissfft)
 
 target_include_directories(kissfft PUBLIC
     $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>
     $<INSTALL_INTERFACE:.>)
+
+set_target_properties(kissfft PROPERTIES
+    DEFINE_SYMBOL KISS_FFT_BUILD)
+if(BUILD_SHARED_LIBS)
+    target_compile_definitions(kissfft PUBLIC KISS_FFT_SHARED)
+    set_target_properties(kissfft PROPERTIES
+        C_VISIBILITY_PRESET hidden)
+endif()
+
+option(KISSFFT_INSTALL "Enable kissfft install" ON)
+if (KISSFFT_INSTALL)
+    include(GNUInstallDirs)
+    install(TARGETS kissfft EXPORT kissfft
+        ARCHIVE DESTINATION "${CMAKE_INSTALL_BINDIR}"
+        LIBRARY DESTINATION "${CMAKE_INSTALL_BINDIR}"
+        RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}")
+    install(FILES "kiss_fft.h" DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}")
+    install(EXPORT kissfft DESTINATION "${CMAKE_INSTALL_LIBDIR}/cmake/${PROJECT_NAME}"
+        NAMESPACE "kissfft::"
+        FILE "${PROJECT_NAME}-config.cmake")
+endif()
diff --git a/kiss_fft.h b/kiss_fft.h
index 25bb720..dce1034 100644
--- a/kiss_fft.h
+++ b/kiss_fft.h
@@ -14,6 +14,21 @@
 #include <math.h>
 #include <string.h>
 
+// Define KISS_FFT_SHARED macro to properly export symbols
+#ifdef KISS_FFT_SHARED
+# ifdef _WIN32
+#  ifdef KISS_FFT_BUILD
+#   define KISS_FFT_API __declspec(dllexport)
+#  else
+#   define KISS_FFT_API __declspec(dllimport)
+#  endif
+# else
+#  define KISS_FFT_API __attribute__ ((visibility ("default")))
+# endif
+#else
+# define KISS_FFT_API
+#endif
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -99,7 +114,7 @@ typedef struct kiss_fft_state* kiss_fft_cfg;
  *      buffer size in *lenmem.
  * */
 
-kiss_fft_cfg kiss_fft_alloc(int nfft,int inverse_fft,void * mem,size_t * lenmem); 
+kiss_fft_cfg KISS_FFT_API kiss_fft_alloc(int nfft,int inverse_fft,void * mem,size_t * lenmem);
 
 /*
  * kiss_fft(cfg,in_out_buf)
@@ -111,12 +126,12 @@ kiss_fft_cfg kiss_fft_alloc(int nfft,int inverse_fft,void * mem,size_t * lenmem)
  * Note that each element is complex and can be accessed like
     f[k].r and f[k].i
  * */
-void kiss_fft(kiss_fft_cfg cfg,const kiss_fft_cpx *fin,kiss_fft_cpx *fout);
+void KISS_FFT_API kiss_fft(kiss_fft_cfg cfg,const kiss_fft_cpx *fin,kiss_fft_cpx *fout);
 
 /*
  A more generic version of the above function. It reads its input from every Nth sample.
  * */
-void kiss_fft_stride(kiss_fft_cfg cfg,const kiss_fft_cpx *fin,kiss_fft_cpx *fout,int fin_stride);
+void KISS_FFT_API kiss_fft_stride(kiss_fft_cfg cfg,const kiss_fft_cpx *fin,kiss_fft_cpx *fout,int fin_stride);
 
 /* If kiss_fft_alloc allocated a buffer, it is one contiguous 
    buffer and can be simply free()d when no longer needed*/
@@ -126,13 +141,13 @@ void kiss_fft_stride(kiss_fft_cfg cfg,const kiss_fft_cpx *fin,kiss_fft_cpx *fout
  Cleans up some memory that gets managed internally. Not necessary to call, but it might clean up 
  your compiler output to call this before you exit.
 */
-void kiss_fft_cleanup(void);
+void KISS_FFT_API kiss_fft_cleanup(void);
 	
 
 /*
  * Returns the smallest integer k, such that k>=n and k has only "fast" factors (2,3,5)
  */
-int kiss_fft_next_fast_size(int n);
+int KISS_FFT_API kiss_fft_next_fast_size(int n);
 
 /* for real ffts, we need an even size */
 #define kiss_fftr_next_fast_size_real(n) \