Probable fix of memory leak

README.md

@@ -36,20 +36,40 @@ in a sister repository in a later stage.
 If you have any question(s), please feel free to contact us: info@ascee.nl.
 
 
-## Installation
+# Building from source
 
-### Compilation
+## Dependencies
 
-#### Archlinux
+Optional dependencies, which can be turned ON/OFF using CMake:
+
+- Build tools, including [http://cmake.org](CMake).
+- FFTW (For really fast FFT's)
+- libUlDAQ, for the Measurement Computing DT9837A USB DAQ box
+    - GNU Autotools, for compiling libUlDAQ
+- RtAudio, for Audio DAQ backends
+- Cython, for wrapping the C-code to Python.
+- The following Python packages need also be available:
+  - `Scipy` (which includes Numpy). Install with `sudo apt install
+    python3-scipy`, or `pacman -S scipy`.
+  - `appdirs`, which can be grabbed from [https://pypi.org](Pypi)
+
+## Installation of dependencies
+
+
+
+
+## Compilation of LASP
+
+### Archlinux
 
 Compiling the code on Archlinux requires the following packages to be available:
 
 - openblas-lapack (AUR)
-- Python 3.7
+- Python>=3.7
 - Numpy (Python-numpy)
 - Cython
 
-#### Ubuntu / Linux Mint
+### Ubuntu / Linux Mint
 
 *Only tested with Linux Mint 18.04*, we require the following packages for
 compilation:
@@ -62,17 +82,3 @@ compilation:
 - libopenblas-base
 - libopenblas-dev
 
-#### Windows specific
-
-Tested using a Anacond / Miniconda Python environment. Please first run the following command:
-
-`conda install fftw`
-
-in case you want the *FFTW* fft backend. 
-
-### Dependencies
-
-#### Ubuntu / Linux Mint
-
-*Only tested with Linux Mint 18.04*. The following Dependencies are required
-for Ubuntu:

lasp/device/lasp_cppuldaq.cpp

@@ -40,7 +40,7 @@ class DT9837A : public Daq {
 
   us nFramesPerBlock;
 
-public:
+  public:
   DT9837A(const DeviceInfo &devinfo, const DaqConfiguration &config)
     : Daq(devinfo, config) {
 
@@ -203,6 +203,40 @@ public:
   friend void threadfcn(DT9837A *);
 };
 
+/**
+ * @brief Create an empty buffer and fill it with zeros.
+ *
+ * @param size The number of elements in the array
+ *
+ * @return Pointer to the array
+ */
+static double* createZeroBuffer(size_t size) {
+
+  double* buf = static_cast<double *>(
+      malloc(sizeof(double) * size));
+
+  for (us sample = 0; sample < size; sample++) {
+    buf[sample] = 0;
+  }
+  return buf;
+}
+/**
+ * @brief Copy samples from one linear array to the next.
+ *
+ * @param[in] from Buffer to copy from
+ * @param[out] to Buffer to copy to
+ * @param startFrom The position to start in the from-buffer
+ * @param startTo The position to start in the to-buffer
+ * @param N The number of samples to copy.
+ */
+static inline void copySamples(double* from,double* to,
+    const us startFrom,const us startTo,const us N) {
+
+  for (us sample = 0; sample < N; sample++) {
+    to[startTo + sample] = from[startFrom + sample];
+  }
+}
+
 void threadfcn(DT9837A *td) {
 
   std::cerr << "Starting DAQ Thread fcn" << endl;
@@ -362,22 +396,16 @@ void threadfcn(DT9837A *td) {
         if (!botoutenqueued) {
           /* cerr << "Copying output buffer to bottom" << endl; */
           double *bufcpy;
+          assert(nenoutchannels > 0);
           if (!outqueue->empty()) {
             bufcpy = (double *)outqueue->dequeue();
           } else {
             cerr << "******* WARNING: OUTPUTQUEUE UNDERFLOW, FILLING SIGNAL "
               "QUEUE WITH ZEROS ***********"
               << endl;
-            bufcpy = static_cast<double *>(
-                malloc(sizeof(double) * nFramesPerBlock * nenoutchannels));
-            for (us sample = 0; sample < nFramesPerBlock; sample++) {
-              bufcpy[sample] = 0;
-            }
-          }
-          assert(nenoutchannels > 0);
-          for (us sample = 0; sample < nFramesPerBlock; sample++) {
-            outbuffer[buffer_mid_idx_out + sample] = bufcpy[sample];
+            bufcpy = createZeroBuffer(nFramesPerBlock*nenoutchannels);
           }
+          copySamples(bufcpy, outbuffer, 0, buffer_mid_idx_out, nFramesPerBlock);
           free(bufcpy);
           botoutenqueued = true;
         }
@@ -386,22 +414,16 @@ void threadfcn(DT9837A *td) {
         if (!topoutenqueued) {
           /* cerr << "Copying output buffer to top" << endl; */
           double *bufcpy;
+          assert(nenoutchannels > 0);
           if (!outqueue->empty()) {
             bufcpy = (double *)outqueue->dequeue();
           } else {
             cerr << "******* WARNING: OUTPUTQUEUE UNDERFLOW, FILLING SIGNAL "
               "QUEUE WITH ZEROS ***********"
               << endl;
-            bufcpy = static_cast<double *>(
-                malloc(sizeof(double) * nFramesPerBlock * nenoutchannels));
-            for (us sample = 0; sample < nFramesPerBlock; sample++) {
-              bufcpy[sample] = 0;
-            }
-          }
-          assert(nenoutchannels > 0);
-          for (us sample = 0; sample < nFramesPerBlock; sample++) {
-            outbuffer[sample] = bufcpy[sample];
+            bufcpy = createZeroBuffer(nFramesPerBlock*nenoutchannels);
           }
+          copySamples(bufcpy, outbuffer, 0, 0, nFramesPerBlock);
           free(bufcpy);
           topoutenqueued = true;
         }