Annotation of 43BSDReno/kerberosIV/make_fp/make_fp.c, revision 1.1.1.1

1.1       root        1: /*
                      2:  * $Source: /mit/kerberos/src/lib/des/RCS/make_fp.c,v $
                      3:  * $Author: jtkohl $
                      4:  *
                      5:  * Copyright 1988 by the Massachusetts Institute of Technology.
                      6:  *
                      7:  * For copying and distribution information,
                      8:  * please see the file <mit-copyright.h>.
                      9:  *
                     10:  * This file contains a generation routine for source code
                     11:  * implementing the final permutation of the DES.
                     12:  */
                     13: 
                     14: #include <mit-copyright.h>
                     15: #include <stdio.h>
                     16: #include "des_internal.h"
                     17: #include "tables.h"
                     18: 
                     19: extern unsigned int swap_bit_pos_0_to_ansi PROTOTYPE((unsigned int));
                     20: extern long swap_long_bytes();
                     21: extern void test_set PROTOTYPE((FILE *, char const *, int,
                     22:                                char const *, int));
                     23: 
                     24: void gen (stream)
                     25:     FILE * stream;
                     26: {
                     27:     register    i;
                     28: 
                     29:     /* clear the output */
                     30:     fprintf(stream,"    L2 = 0; R2 = 0;\n");
                     31: 
                     32:     /*
                     33:      *  NOTE: As part of the final permutation, we also have to adjust
                     34:      *  for host bit order via "swap_bit_pos_0()".  Since L2,R2 are
                     35:      *  the output from this, we adjust the bit positions written into
                     36:      *  L2,R2.
                     37:      */
                     38: 
                     39: #define SWAP(i,j) \
                     40:     swap_long_bytes_bit_number(swap_bit_pos_0_to_ansi((unsigned)i)-j)
                     41: 
                     42:     /* first setup FP */
                     43:     fprintf(stream,
                     44:             "/* FP operations */\n/* first left to left */\n");
                     45: 
                     46:     /* first list mapping from left to left */
                     47:     for (i = 0; i <= 31; i++)
                     48:         if (FP[i] < 32)
                     49:             test_set(stream, "L1", FP[i], "L2", SWAP(i,0));
                     50: 
                     51:     /* now mapping from right to left */
                     52:     fprintf(stream,"\n\n/* now from right to left */\n");
                     53:     for (i = 0; i <= 31; i++)
                     54:         if (FP[i] >= 32)
                     55:             test_set(stream, "R1", FP[i]-32, "L2", SWAP(i,0));
                     56: 
                     57:     fprintf(stream,"\n/* now from left to right */\n");
                     58: 
                     59:     /*  list mapping from left to right */
                     60:     for (i = 32; i <= 63; i++)
                     61:         if (FP[i] <32)
                     62:             test_set(stream, "L1", FP[i], "R2", SWAP(i,32));
                     63: 
                     64:     /* now mapping from right to right */
                     65:     fprintf(stream,"\n/* last from right to right */\n");
                     66:     for (i = 32; i <= 63; i++)
                     67:         if (FP[i] >= 32)
                     68:             test_set(stream, "R1", FP[i]-32, "R2", SWAP(i,32));
                     69: }

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