Switch extensions from .c to .cc and fix compile time errors

setup.py

@@ -18,29 +18,30 @@
         "kiss_fft_int16.cc",
         "fft.cc",
         "fft_util.cc",
-        "filterbank.c",
-        "filterbank_util.c",
-        "frontend.c",
-        "frontend_util.c",
-        "log_lut.c",
-        "log_scale.c",
-        "log_scale_util.c",
-        "noise_reduction.c",
-        "noise_reduction_util.c",
-        "pcan_gain_control.c",
-        "pcan_gain_control_util.c",
-        "window.c",
-        "window_util.c",
+        "filterbank.cc",
+        "filterbank_util.cc",
+        "frontend.cc",
+        "frontend_util.cc",
+        "log_lut.cc",
+        "log_scale.cc",
+        "log_scale_util.cc",
+        "noise_reduction.cc",
+        "noise_reduction_util.cc",
+        "pcan_gain_control.cc",
+        "pcan_gain_control_util.cc",
+        "window.cc",
+        "window_util.cc",
     ]
 )
-sources.append(_KISSFFT_DIR / "kiss_fft.c")
-sources.append(_KISSFFT_DIR / "tools" / "kiss_fftr.c")
+sources.append(_KISSFFT_DIR / "kiss_fft.cc")
+sources.append(_KISSFFT_DIR / "tools" / "kiss_fftr.cc")
 
 flags = ["-DFIXED_POINT=16"]
 ext_modules = [
     Pybind11Extension(
         name="micro_features_cpp",
         language="c++",
+        cxx_std=17,
         extra_compile_args=flags,
         sources=sorted([str(p) for p in sources] + [str(_DIR / "python.cpp")]),
         define_macros=[("VERSION_INFO", __version__)],

tensorflow/lite/experimental/microfrontend/lib/filterbank_util.c → tensorflow/lite/experimental/microfrontend/lib/filterbank_util.cc

@@ -66,19 +66,19 @@ int FilterbankPopulateState(const struct FilterbankConfig* config,
            : kFilterbankIndexAlignment / sizeof(int16_t));
 
   state->channel_frequency_starts =
-      malloc(num_channels_plus_1 * sizeof(*state->channel_frequency_starts));
+      (int16_t*)malloc(num_channels_plus_1 * sizeof(*state->channel_frequency_starts));
   state->channel_weight_starts =
-      malloc(num_channels_plus_1 * sizeof(*state->channel_weight_starts));
+      (int16_t*)malloc(num_channels_plus_1 * sizeof(*state->channel_weight_starts));
   state->channel_widths =
-      malloc(num_channels_plus_1 * sizeof(*state->channel_widths));
-  state->work = malloc(num_channels_plus_1 * sizeof(*state->work));
+      (int16_t*)malloc(num_channels_plus_1 * sizeof(*state->channel_widths));
+  state->work = (uint64_t*)malloc(num_channels_plus_1 * sizeof(*state->work));
 
   float* center_mel_freqs =
-      malloc(num_channels_plus_1 * sizeof(*center_mel_freqs));
+      (float*)malloc(num_channels_plus_1 * sizeof(*center_mel_freqs));
   int16_t* actual_channel_starts =
-      malloc(num_channels_plus_1 * sizeof(*actual_channel_starts));
+      (int16_t*)malloc(num_channels_plus_1 * sizeof(*actual_channel_starts));
   int16_t* actual_channel_widths =
-      malloc(num_channels_plus_1 * sizeof(*actual_channel_widths));
+      (int16_t*)malloc(num_channels_plus_1 * sizeof(*actual_channel_widths));
 
   if (state->channel_frequency_starts == NULL ||
       state->channel_weight_starts == NULL || state->channel_widths == NULL ||
@@ -160,8 +160,8 @@ int FilterbankPopulateState(const struct FilterbankConfig* config,
   // Allocate the two arrays to store the weights - weight_index_start contains
   // the index of what would be the next set of weights that we would need to
   // add, so that's how many weights we need to allocate.
-  state->weights = calloc(weight_index_start, sizeof(*state->weights));
-  state->unweights = calloc(weight_index_start, sizeof(*state->unweights));
+  state->weights = (int16_t*)calloc(weight_index_start, sizeof(*state->weights));
+  state->unweights = (int16_t*)calloc(weight_index_start, sizeof(*state->unweights));
 
   // If the alloc failed, we also need to nuke the arrays.
   if (state->weights == NULL || state->unweights == NULL) {

tensorflow/lite/experimental/microfrontend/lib/kiss_fft_int16.cc

@@ -4,7 +4,7 @@
 
 #define FIXED_POINT 16
 namespace kissfft_fixed16 {
-#include "kiss_fft.c"
-#include "tools/kiss_fftr.c"
+#include "kiss_fft.cc"
+#include "tools/kiss_fftr.cc"
 }  // namespace kissfft_fixed16
 #undef FIXED_POINT

tensorflow/lite/experimental/microfrontend/lib/noise_reduction_util.c → tensorflow/lite/experimental/microfrontend/lib/noise_reduction_util.cc

@@ -32,7 +32,7 @@ int NoiseReductionPopulateState(const struct NoiseReductionConfig* config,
   state->min_signal_remaining =
       config->min_signal_remaining * (1 << kNoiseReductionBits);
   state->num_channels = num_channels;
-  state->estimate = calloc(state->num_channels, sizeof(*state->estimate));
+  state->estimate = (uint32_t*)calloc(state->num_channels, sizeof(*state->estimate));
   if (state->estimate == NULL) {
     fprintf(stderr, "Failed to alloc estimate buffer\n");
     return 0;

tensorflow/lite/experimental/microfrontend/lib/pcan_gain_control_util.c → tensorflow/lite/experimental/microfrontend/lib/pcan_gain_control_util.cc

@@ -52,7 +52,7 @@ int PcanGainControlPopulateState(const struct PcanGainControlConfig* config,
   }
   state->noise_estimate = noise_estimate;
   state->num_channels = num_channels;
-  state->gain_lut = malloc(kWideDynamicFunctionLUTSize * sizeof(int16_t));
+  state->gain_lut = (int16_t*)malloc(kWideDynamicFunctionLUTSize * sizeof(int16_t));
   if (state->gain_lut == NULL) {
     fprintf(stderr, "Failed to allocate gain LUT\n");
     return 0;

tensorflow/lite/experimental/microfrontend/lib/window_util.c → tensorflow/lite/experimental/microfrontend/lib/window_util.cc

@@ -34,7 +34,7 @@ int WindowPopulateState(const struct WindowConfig* config,
   state->size = config->size_ms * sample_rate / 1000;
   state->step = config->step_size_ms * sample_rate / 1000;
 
-  state->coefficients = malloc(state->size * sizeof(*state->coefficients));
+  state->coefficients = (int16_t*)malloc(state->size * sizeof(*state->coefficients));
   if (state->coefficients == NULL) {
     fprintf(stderr, "Failed to allocate window coefficients\n");
     return 0;
@@ -51,13 +51,13 @@ int WindowPopulateState(const struct WindowConfig* config,
   }
 
   state->input_used = 0;
-  state->input = malloc(state->size * sizeof(*state->input));
+  state->input = (int16_t*)malloc(state->size * sizeof(*state->input));
   if (state->input == NULL) {
     fprintf(stderr, "Failed to allocate window input\n");
     return 0;
   }
 
-  state->output = malloc(state->size * sizeof(*state->output));
+  state->output = (int16_t*)malloc(state->size * sizeof(*state->output));
   if (state->output == NULL) {
     fprintf(stderr, "Failed to allocate window output\n");
     return 0;