1 files changed, 99 insertions, 0 deletions
diff --git a/src/lockin.h b/src/lockin.h
new file mode 100644
index 0000000..9a6a515
--- /dev/null
+++ b/src/lockin.h
@@ -0,0 +1,99 @@
+#ifndef LOCKIN_H
+#define LOCKIN_H
+#include <limits.h>             /* for INT_MAX */
+#include <valarray>
+#include <cmath>
+#include <string>
+#include "alsa_pcm.h"
+
+// used when converting between syslog and fprintf:
+#define NL "\n"
+
+const double two16(1<<16);
+const double two32(two16*two16);
+const int bPB(8);               // bits per byte
+void exeunt(int signum);
+std::string invent_driverfile(const std::string justcard);
+std::string invent_ctlfile(const std::string justcard);
+
+typedef int32_t datum;          // all internal calculations are 32bit
+
+const double pi(M_PI);
+const double kT(1.38e-23 * (273.15 + 20));
+const double twopi = 2 * pi;
+
+// reference level is saturation minus 15 dB
+const double full_swing(INT_MAX);
+
+// sine wave RMS is sqrt(2) less than peak:
+const double full_swing_2(full_swing/sqrt(2.0));
+
+// some non-constant global variables,
+// for inter-thread communication:
+extern std::string progname;
+extern int verbosity;
+extern timespec prog_start_time;
+extern int xrun_verbosity;       // be verbose about underrun and overrun
+//
+// Note: more globals are found in gui.h
+
+inline double operator-(const timespec a, const timespec b){
+  return (a.tv_sec-b.tv_sec) + (a.tv_nsec - b.tv_nsec)*1e-9;
+}
+
+class Keeper{
+public:
+  const alsa_pcm* pcm;
+  const int fpp;                // frames per period
+  std::valarray<datum> buf;
+  int finbuf;                   // frames in buffer at the moment
+  int nchan;
+  Keeper(const alsa_pcm*, const int fsize);
+};
+
+snd_pcm_sframes_t snd_pcm_writei(Keeper& kk, const datum* buffer,
+        snd_pcm_uframes_t nframes);
+
+
+class snark {
+public:
+  snark();              // constructor
+  std::string card_device;   // principal input, e.g. "0,0"
+  std::string wcheck_fname;  // place to write raw data (checkfile)
+  int nframe;
+  int onepass;          // exit after one pass
+  int desired_rate;
+  int channel_mask;
+  double kout;  // output voltage scale, assuming sine-wave
+                        // ... which has RMS 3dB below full_swing
+  double zref;          // reference resistor
+  double reffreq;
+  double refival;
+  double refamp;
+  std::string mixer_ctlfile;
+
+
+// not commandline options, but derived therefrom:
+  int wcheck_fd;
+  std::string justcard;      // the "card" part of that, before the comman
+  double sps;           // entropy (bits per sample)
+  double snooze;        // time to snooze between actions if not
+                        //   actually writing to output fifo,
+                        //   e.g. during calibration.
+
+//// functions
+  void usage(const int err);
+  void cmdline(int argc, char** argv);
+  void open_aux_io();
+  int read_stuff(alsa_pcm*, datum*);
+  void printx(
+   const int colored,
+   const char* name,
+   const double foo_1,
+   const double foo_2,
+   double plogp,
+   const alsa_pcm* pcm
+  );
+};
+
+#endif