Initial Commit

2018-02-08 21:28:33 -05:00
commit 678c1d3966
14352 changed files with 3176737 additions and 0 deletions
@@ -0,0 +1,47 @@
+/* Reed-Solomon encoder
+ * Copyright 2002, Phil Karn, KA9Q
+ * May be used under the terms of the GNU General Public License (GPL)
+ */
+#include <string.h>
+
+#ifdef FIXED
+#include "fixed.h"
+#elif defined(BIGSYM)
+#include "int.h"
+#else
+#include "char.h"
+#endif
+
+void ENCODE_RS(
+#ifndef FIXED
+void *p,
+#endif
+DTYPE *data, DTYPE *bb){
+#ifndef FIXED
+  struct rs *rs = (struct rs *)p;
+#endif
+  int i, j;
+  DTYPE feedback;
+
+  memset(bb,0,NROOTS*sizeof(DTYPE));
+
+  for(i=0;i<NN-NROOTS;i++){
+    feedback = INDEX_OF[data[i] ^ bb[0]];
+    if(feedback != A0){      /* feedback term is non-zero */
+#ifdef UNNORMALIZED
+      /* This line is unnecessary when GENPOLY[NROOTS] is unity, as it must
+       * always be for the polynomials constructed by init_rs()
+       */
+      feedback = MODNN(NN - GENPOLY[NROOTS] + feedback);
+#endif
+      for(j=1;j<NROOTS;j++)
+	bb[j] ^= ALPHA_TO[MODNN(feedback + GENPOLY[NROOTS-j])];
+    }
+    /* Shift */
+    memmove(&bb[0],&bb[1],sizeof(DTYPE)*(NROOTS-1));
+    if(feedback != A0)
+      bb[NROOTS-1] = ALPHA_TO[MODNN(feedback + GENPOLY[0])];
+    else
+      bb[NROOTS-1] = 0;
+  }
+}