build: add libsndfile

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "src/ext/libsndfile"]
+	path = src/ext/libsndfile
+	url = https://github.com/libsndfile/libsndfile.git

CMakeLists.txt

@@ -0,0 +1,61 @@
+cmake_minimum_required(VERSION 4.1)
+project(rubberband)
+
+set(CMAKE_CXX_STANDARD 20)
+
+set(CMAKE_CXX_FLAGS "-DNOMINMAX -DUSE_BQRESAMPLER -DHAVE_KISSFFT")
+
+#include_directories(mpg123/lib/x86_64/include)
+include_directories(
+./dotnet/rubberband-dll
+./ladspa-lv2
+./rubberband
+./src/common
+./src/ext/float_cast
+./src/ext/getopt
+./src/ext/kissfft
+./src/ext/pommier
+./src/ext/speex
+./src/faster
+./src/finer
+./vamp
+)
+
+add_executable(rubberband
+./src/ext/getopt/getopt.c
+./src/ext/getopt/getopt_long.c
+./src/ext/kissfft/kiss_fft.c
+./src/ext/kissfft/kiss_fftr.c
+./src/ext/speex/resample.c
+./main/main.cpp
+./src/common/Allocators.cpp
+./src/common/BQResampler.cpp
+./src/common/FFT.cpp
+./src/common/Log.cpp
+./src/common/mathmisc.cpp
+./src/common/Profiler.cpp
+./src/common/Resampler.cpp
+./src/common/StretchCalculator.cpp
+./src/common/sysutils.cpp
+./src/common/Thread.cpp
+./src/common/VectorOpsComplex.cpp
+./src/faster/AudioCurveCalculator.cpp
+./src/faster/CompoundAudioCurve.cpp
+./src/faster/HighFrequencyAudioCurve.cpp
+./src/faster/PercussiveAudioCurve.cpp
+./src/faster/R2Stretcher.cpp
+./src/faster/SilentAudioCurve.cpp
+./src/faster/StretcherChannelData.cpp
+./src/faster/StretcherProcess.cpp
+./src/finer/R3LiveShifter.cpp
+./src/finer/R3Stretcher.cpp
+./src/rubberband-c.cpp
+./src/RubberBandLiveShifter.cpp
+./src/RubberBandStretcher.cpp
+)
+#target_link_directories(rubberband PRIVATE mpg123/lib/x86_64)
+#target_link_libraries(test_lockstep mpg123-0)
+#target_link_libraries(rubberband ${CMAKE_SOURCE_DIR}/mpg123/lib/x86_64/libmpg123.dll.a)
+
+add_subdirectory(src/ext/libsndfile)
+target_link_libraries(rubberband sndfile)