Initial Commit

2018-02-08 21:28:33 -05:00
commit 678c1d3966
14352 changed files with 3176737 additions and 0 deletions
@@ -0,0 +1,51 @@
+subroutine extractmessage144(decoded,msgreceived,nhashflag,recent_calls,nrecent)
+  use iso_c_binding, only: c_loc,c_size_t
+  use packjt
+  use hashing
+
+  character*22 msgreceived
+  character*12 call1,call2
+  character*12 recent_calls(nrecent)
+  integer*1 decoded(80)
+  integer*1, target::  i1Dec8BitBytes(10)
+  integer*1 i1hashdec
+  integer*4 i4Dec6BitWords(12)
+
+! Collapse 80 decoded bits to 10 bytes. Bytes 1-9 are the message, byte 10 is the hash
+  do ibyte=1,10
+      itmp=0
+    do ibit=1,8
+      itmp=ishft(itmp,1)+iand(1,decoded((ibyte-1)*8+ibit))
+    enddo
+    i1Dec8BitBytes(ibyte)=itmp
+  enddo
+
+! Calculate the hash using the first 9 bytes.
+  ihashdec=nhash(c_loc(i1Dec8BitBytes),int(9,c_size_t),146)
+  ihashdec=2*iand(ihashdec,255)
+
+! Compare calculated hash with received byte 10 - if they agree, keep the message.
+  i1hashdec=ihashdec
+  if( i1hashdec .eq. i1Dec8BitBytes(10) ) then
+! Good hash --- unpack 72-bit message
+    do ibyte=1,12
+      itmp=0
+      do ibit=1,6
+        itmp=ishft(itmp,1)+iand(1,decoded((ibyte-1)*6+ibit))
+      enddo
+      i4Dec6BitWords(ibyte)=itmp
+    enddo
+    call unpackmsg144(i4Dec6BitWords,msgreceived,call1,call2)
+    nhashflag=1
+    if( call1(1:2) .ne. 'CQ' .and. call1(1:2) .ne. '  ' ) then
+      call update_recent_calls(call1,recent_calls,nrecent)
+    endif
+    if( call2(1:2) .ne. '  ' ) then
+      call update_recent_calls(call2,recent_calls,nrecent)
+    endif
+  else
+    msgreceived=' '
+    nhashflag=-1
+  endif 
+  return
+  end subroutine extractmessage144