added mutex lock on write to fftw input buffers and fftw execute

this will prevent an fftw execute from taking place while data is
beeing written to buffers

cava.c

@@ -63,6 +63,7 @@
 // struct termios oldtio, newtio;
 // int M = 8 * 1024;
 
+pthread_mutex_t lock;
 // used by sig handler
 // needs to know output mode in order to clean up terminal
 int output_mode;
@@ -875,12 +876,14 @@ as of 0.4.0 all options are specified in config file, see in '/home/username/.co
 
                     // process: execute FFT and sort frequency bands
                     if (p.stereo) {
+                        pthread_mutex_lock(&lock);
                         fftw_execute(p_bass_l);
                         fftw_execute(p_bass_r);
                         fftw_execute(p_mid_l);
                         fftw_execute(p_mid_r);
                         fftw_execute(p_treble_l);
                         fftw_execute(p_treble_r);
+                        pthread_mutex_unlock(&lock);
 
                         bars_left = separate_freq_bands(
                             audio.FFTbassbufferSize, out_bass_l, audio.FFTmidbufferSize, out_mid_l,
@@ -895,9 +898,12 @@ as of 0.4.0 all options are specified in config file, see in '/home/username/.co
                             FFTbuffer_upper_cut_off, eq, RIGHT_CHANNEL, p.sens, p.ignore);
 
                     } else {
+                        pthread_mutex_lock(&lock);
                         fftw_execute(p_bass_l);
                         fftw_execute(p_mid_l);
                         fftw_execute(p_treble_l);
+                        pthread_mutex_unlock(&lock);
+
                         bars_mono = separate_freq_bands(
                             audio.FFTbassbufferSize, out_bass_l, audio.FFTmidbufferSize, out_mid_l,
                             audio.FFTtreblebufferSize, out_treble_l, bass_cut_off_bar,

input/alsa.c

@@ -156,7 +156,9 @@ void *input_alsa(void *data) {
             debug("short read, read %d %d frames\n", err, (int)frames);
         }
 
-        write_to_fftw_input_buffers(buf, frames, data);
+        pthread_mutex_lock(&lock);
+        write_to_fftw_input_buffers(frames, buf, data);
+        pthread_mutex_unlock(&lock);
     }
 
     free(buffer);

input/common.c

@@ -11,7 +11,7 @@ void reset_output_buffers(struct audio_data *data) {
     memset(data->in_treble_l, 0, sizeof(double) * 2 * (data->FFTtreblebufferSize / 2 + 1));
 }
 
-int write_to_fftw_input_buffers(int16_t buf[], int16_t frames, void *data) {
+int write_to_fftw_input_buffers(int16_t frames, int16_t buf[frames * 2], void *data) {
     struct audio_data *audio = (struct audio_data *)data;
 
     for (uint16_t i = 0; i < frames * 2; i += 2) {

input/common.h

@@ -33,4 +33,6 @@ struct audio_data {
 
 void reset_output_buffers(struct audio_data *data);
 
-int write_to_fftw_input_buffers(int16_t buf[], int16_t frames, void *data);
+int write_to_fftw_input_buffers(int16_t frames, int16_t buf[frames * 2], void *data);
+
+extern pthread_mutex_t lock;

input/fifo.c

@@ -67,7 +67,9 @@ void *input_fifo(void *data) {
 
         // We worked with unsigned ints up until now to save on sign extension, but the FFT wants
         // signed ints.
-        write_to_fftw_input_buffers((int16_t *)samples, SAMPLES_PER_BUFFER / 2, audio);
+        pthread_mutex_lock(&lock);
+        write_to_fftw_input_buffers(SAMPLES_PER_BUFFER / 2, (int16_t *)samples, audio);
+        pthread_mutex_unlock(&lock);
     }
 
     close(fd);

input/portaudio.c

@@ -41,7 +41,9 @@ static int recordCallback(const void *inputBuffer, void *outputBuffer,
     }
 
     if (inputBuffer == NULL) {
-        write_to_fftw_input_buffers(silence_buffer, framesToCalc, audio);
+        pthread_mutex_lock(&lock);
+        write_to_fftw_input_buffers(framesToCalc, silence_buffer, audio);
+        pthread_mutex_unlock(&lock);
         /*
                         for(i=0; i<framesToCalc; i++) {
                                 if(audio->channels == 1) audio->audio_out_l[n] = SAMPLE_SILENCE;
@@ -53,7 +55,7 @@ static int recordCallback(const void *inputBuffer, void *outputBuffer,
                         }
         */
     } else {
-        write_to_fftw_input_buffers(rptr, framesToCalc, audio);
+        write_to_fftw_input_buffers(framesToCalc, rptr, audio);
         /*
                         for(i=0; i<framesToCalc; i++) {
                                 if(audio->channels == 1) {

input/pulse.c

@@ -131,9 +131,9 @@ void *input_pulse(void *data) {
             audio->terminate = 1;
         }
 
-        // sorting out channels
-
-        write_to_fftw_input_buffers(buf, frames, data);
+        pthread_mutex_lock(&lock);
+        write_to_fftw_input_buffers(frames, buf, data);
+        pthread_mutex_unlock(&lock);
     }
 
     pa_simple_free(s);

input/shmem.c

@@ -65,10 +65,12 @@ void *input_shmem(void *data) {
             // Thus, the starting position only affects the phase spectrum of the
             // fft, and not the power spectrum, so we can just read in the
             // whole buffer.
-            write_to_fftw_input_buffers(mmap_area->buffer, buf_frames, audio);
+            pthread_mutex_lock(&lock);
+            write_to_fftw_input_buffers(buf_frames, mmap_area->buffer, audio);
+            pthread_mutex_unlock(&lock);
             nanosleep(&req, NULL);
         } else {
-            write_to_fftw_input_buffers(silence_buffer, buf_frames, audio);
+            write_to_fftw_input_buffers(buf_frames, silence_buffer, audio);
             nanosleep(&req, NULL);
         }
     }

input/sndio.c

@@ -41,19 +41,9 @@ void *input_sndio(void *data) {
             exit(EXIT_FAILURE);
         }
 
-        write_to_fftw_input_buffers(buf, frames, audio);
-        /*
-                        for (i = 0; i < sizeof(buf)/sizeof(buf[0]); i += 2) {
-                                if (par.rchan == 1) {
-                                        // sndiod has already taken care of averaging the samples
-                                        audio->audio_out_l[n] = buf[i];
-                                } else if (par.rchan == 2) {
-                                        audio->audio_out_l[n] = buf[i];
-                                        audio->audio_out_r[n] = buf[i + 1];
-                                }
-                                n = (n + 1) % audio->FFTbufferSize;
-                        }
-        */
+        pthread_mutex_lock(&lock);
+        write_to_fftw_input_buffers(frames, buf, audio);
+        pthread_mutex_unlock(&lock);
     }
 
     sio_stop(hdl);