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authorMatthias P. Braendli <matthias.braendli@mpb.li>2014-01-02 21:55:13 +0100
committerMatthias P. Braendli <matthias.braendli@mpb.li>2014-01-02 21:55:13 +0100
commita31630e0d5b9880c716d9004ef4154396ba41ebc (patch)
treeaebbd3b132e5f2dd31bc34750ccded2378fc687a /fec.c
parent9aaac5be9db5e1537badc65242412ef14c5096e3 (diff)
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Extract fec-3.0.1
Diffstat (limited to 'fec.c')
-rw-r--r--fec.c66
1 files changed, 66 insertions, 0 deletions
diff --git a/fec.c b/fec.c
new file mode 100644
index 0000000..35960c3
--- /dev/null
+++ b/fec.c
@@ -0,0 +1,66 @@
+/* Utility routines for FEC support
+ * Copyright 2004, Phil Karn, KA9Q
+ */
+
+#include <stdio.h>
+#include "fec.h"
+
+unsigned char Partab[256];
+int P_init;
+
+/* Create 256-entry odd-parity lookup table
+ * Needed only on non-ia32 machines
+ */
+void partab_init(void){
+ int i,cnt,ti;
+
+ /* Initialize parity lookup table */
+ for(i=0;i<256;i++){
+ cnt = 0;
+ ti = i;
+ while(ti){
+ if(ti & 1)
+ cnt++;
+ ti >>= 1;
+ }
+ Partab[i] = cnt & 1;
+ }
+ P_init=1;
+}
+
+/* Lookup table giving count of 1 bits for integers 0-255 */
+int Bitcnt[] = {
+ 0, 1, 1, 2, 1, 2, 2, 3,
+ 1, 2, 2, 3, 2, 3, 3, 4,
+ 1, 2, 2, 3, 2, 3, 3, 4,
+ 2, 3, 3, 4, 3, 4, 4, 5,
+ 1, 2, 2, 3, 2, 3, 3, 4,
+ 2, 3, 3, 4, 3, 4, 4, 5,
+ 2, 3, 3, 4, 3, 4, 4, 5,
+ 3, 4, 4, 5, 4, 5, 5, 6,
+ 1, 2, 2, 3, 2, 3, 3, 4,
+ 2, 3, 3, 4, 3, 4, 4, 5,
+ 2, 3, 3, 4, 3, 4, 4, 5,
+ 3, 4, 4, 5, 4, 5, 5, 6,
+ 2, 3, 3, 4, 3, 4, 4, 5,
+ 3, 4, 4, 5, 4, 5, 5, 6,
+ 3, 4, 4, 5, 4, 5, 5, 6,
+ 4, 5, 5, 6, 5, 6, 6, 7,
+ 1, 2, 2, 3, 2, 3, 3, 4,
+ 2, 3, 3, 4, 3, 4, 4, 5,
+ 2, 3, 3, 4, 3, 4, 4, 5,
+ 3, 4, 4, 5, 4, 5, 5, 6,
+ 2, 3, 3, 4, 3, 4, 4, 5,
+ 3, 4, 4, 5, 4, 5, 5, 6,
+ 3, 4, 4, 5, 4, 5, 5, 6,
+ 4, 5, 5, 6, 5, 6, 6, 7,
+ 2, 3, 3, 4, 3, 4, 4, 5,
+ 3, 4, 4, 5, 4, 5, 5, 6,
+ 3, 4, 4, 5, 4, 5, 5, 6,
+ 4, 5, 5, 6, 5, 6, 6, 7,
+ 3, 4, 4, 5, 4, 5, 5, 6,
+ 4, 5, 5, 6, 5, 6, 6, 7,
+ 4, 5, 5, 6, 5, 6, 6, 7,
+ 5, 6, 6, 7, 6, 7, 7, 8,
+};
+