Usenet 1994 January/usenetsourcesnewsgroupsinfomagicjanuary1994.iso/sources/unix/volume10/cbw/part02/bdriver.c

C/C++ Source or Header | 1987-06-16 | 3.8 KB | 198 lines

/*
 * Test driver for BIGRAM character guessing stuff.
 */

#include    <stdio.h>
#include    <math.h>
#include    "window.h"
#include    "specs.h"
#include    "cipher.h"


#define NDOBLOCKS    2        /* Number of blocks to do. */
#define    DEBUG        FALSE

ecinfo    myecinfo;

char    plainbuf[BLOCKSIZE+1];
float    accept_level;
float    prob_cutoff;

extern    ec_best(), ec_dplain(), ec_dscipher();
extern    ec_dnext(), ec_dsizetab(), ec_dperm(), ec_dpmap();
extern    ec_init(), ec_best(), ec_cscore();
extern    lp_init(), lp_best_char(), lp_cscore(), lp_accept(), lp_best_pos();
extern    lp_dclasses();

extern    char    mcbuf[];
extern    char    *fname;            /* Used by fillcbuf. */
/* Test routine for equiv class info. */
main(argc, argv)
int        argc;
char    *argv[];
{
    ecinfo    *eci;
    FILE    *inp;
    FILE    *sout, *sin;
    int        i, blknum;
    int        maxblock;
    long    filelength;
    char    infile[100];
    char    inplain[100];
    char    *plain = ".txt";
    char    *code = ".cipher";
    char    *p, *q;

    sout = stdout;        /* For use within debugger, dbx. */
    sin = stdin;

    if (argc != 4)  {
        printf("Usage: %s input_file_root acceptance_level prob_cutoff\n",
                argv[0]);
        exit(0);
        }

    p = inplain;
    q = argv[1];
    while (*p++ = *q++);
    --p;
    q = plain;
    while (*p++ = *q++);

    p = infile;
    q = argv[1];
    while (*p++ = *q++);
    --p;
    q = code;
    while (*p++ = *q++);

    if (sscanf(argv[2], "%f", &accept_level) != 1)  {
        printf("Could not parse the acceptance level from %s.\n", argv[2]);
        exit(0);
        }

    if (sscanf(argv[3], "%f", &prob_cutoff) != 1)  {
        printf("Could not parse the probability cutoff from %s.\n", argv[2]);
        exit(0);
        }

    printf("\t\tEquivalence Class Guessing\n\n");
    printf("Filename = %s.  Acceptance level = %4.2f\n",infile,accept_level);

    printf("Loading statistics ...");
    printf(" 1");
    load_1stats_from("mss.stats");
    printf(" 2");
    load_2stats_from("mss-bigram.stats");
    printf(" done.\n");

    eci = &myecinfo;

    if ((inp = fopen(infile, "r")) == NULL) {
        printf("\nCannot open %s for reading.\n", infile);
        exit(0);
        }
    fseek(inp, 0L, 2);
    filelength = ftell(inp);
    fclose(inp);

    maxblock = filelength / BLOCKSIZE;
    if (maxblock > (NDOBLOCKS-1))  maxblock = (NDOBLOCKS-1);

    for (blknum = 0 ; blknum <= maxblock ; blknum++) {
        do_lp_block(eci, blknum, infile, inplain);
        }
}


/* Do a block using the letter pair statistics.
 */
do_lp_block(eci, blknum, cfile, plainfile)
reg        ecinfo    *eci;
int        blknum;
char    *cfile, *plainfile;
{
    int        i;
reg    int        c;
    int        ntried;
    int        naccepted, nwrong;
reg    int        classpos;
    int        charcount;
    int        *permp, repeat;

    cipherfile = cfile;
    fillcbuf(blknum, mcbuf);
    cipherfile = plainfile;
    fillcbuf(blknum, plainbuf);

    lp_init(mcbuf, refperm(blknum), eci);

for(repeat = 0 ; repeat < 3 ; repeat++)  {
    naccepted = 0;
    nwrong = 0;
    ntried = 0;

    for (ntried = 0 ; ntried < BLOCKSIZE ; ntried++)  {
        classpos = lp_best_pos(eci, 2);
        if (classpos == NONE)
            break;
        c = lp_best_char(eci, classpos,
                        accept_level - ((repeat == 0) ? 0.0 : 0.0),
                        prob_cutoff);
        if (c != NONE) {
            lp_accept(eci, classpos, c);
            naccepted++;
#if DEBUG
            printf("ACCEPTED");
#endif
            if (plainbuf[classpos] != c)  {
                nwrong++;
#if DEBUG
                printf(" -- INCORRECT");
#endif
                }
#if DEBUG
            printf("\n");
#endif
            }
        }

/*    decode(eci->ciphertext, eci->plaintext, eci->perm);
*/

    for (i = 0 ; i < eci->nclasses ; i++)  {
        eci->classlist[i].changed = TRUE;
        }


    charcount = 0;
     for (i = 0 ; i < BLOCKSIZE ; i++)  {
        if (eci->plaintext[i] != NONE)  charcount++;
        }

    printf("\n\nPlaintext for block %d using %d wires", blknum, naccepted);
    printf(" (%d wrong)", nwrong);
    printf(" yields %d characters.", charcount);
    printf("\nThere were %d classes and %d guess tries.",eci->nclasses,ntried);
    printf("\n\n");
    ec_dplain(stdout, eci);
    }

    permp = refperm(blknum);
    for (i = 0 ; i < BLOCKSIZE ; i++)  {
        permp[i] = eci->perm[i];
        }
}


key    u_getkey()
{
}

keyer    topktab[] ={{0, NULL}};


char    *quitcmd()
{
}