www.pudn.com > cryptfs030905.rar > sca_read.c

/*
 * Copyright (c) 1997-2003 Erez Zadok
 * Copyright (c) 2001-2003 Stony Brook University
 *
 * For specific licensing information, see the COPYING file distributed with
 * this package, or get one from ftp://ftp.filesystems.org/pub/fist/COPYING.
 *
 * This Copyright notice must be kept intact and distributed with all
 * fistgen sources INCLUDING sources generated by fistgen.
 */
/*
 *  $Id: sca_read.c,v 1.8 2003/07/29 18:17:21 ezk Exp $
 */
#include 
#include 
#include 
#include 
#include 
#include 
#include 

#include "sca_aux.h"
#include "sca_code.h"	/* replace with your definitions of en/decode _page */


int
decode_file(char *name)
{
    char idx[MAXPATHLEN];
    int srcfd;
    struct fistfs_header hdr;
    int i, len;
    unsigned char *out;

    if (name == NULL)
	return(-1);

    if ((srcfd = open(name, O_RDONLY)) < 0)
	return(-1);

    sprintf(idx, "%s.idx", name);
    if ((read_idx(idx, &hdr)) < 0)
	return(-1); /* read the header */

    for (i = 0; i < hdr.num_pages; i++) {
	if ((get_page(srcfd, &hdr, i, &out, &len)) < 0) {
	    fprintf(stderr, "get_page returns error!\n");
	    return(-1);
	}

	if (len > chunksize) {
	    fprintf(stderr, "***decode returned %d bytes\n", len);
	}
	write(1, out, len);
	free(out);
    }

    if (do_fast_tails) {	/* See if there unencoded data at the end */
	/* This get_page will return 0 if there is no unencoded tail */
	if ((get_page(srcfd, &hdr, i, &out, &len)) < 0) {
	    fprintf(stderr,"get_page returns error!\n");
	    return(-1);
	}
	write(1, out, len);
	free(out);
    }
    return(0);
}


void
usage(const char *progname)
{
    fprintf(stderr,
	    "Usage: %s [-c chunksize] [-d] [-f] file1 [file2 file3 ...]\n",
	    progname);
}


int
main(int argc, char **argv)
{
    int i, rc, cnt = 0;
    int debug = 0;
    char *name;

    if (argc < 2) {
	usage(argv[0]);
	exit(1);
    }

    while ((i = getopt(argc, argv, "c:df")) != EOF) {
	switch(i) {
	case 'c':
	    chunksize = atoi(optarg);
	    if (chunksize < 0) {
		fprintf(stderr, "Please use a positive chunk size\n");
		exit(1);
	    }
	    break;
	case 'f':
	    do_fast_tails = 1;
	    break;
	case 'd':
	    debug = 1;
	    break;
	default:
	    usage(argv[0]);
	    exit(1);
	}
    }

    for (i = optind; i < argc; i++) {
	name = strdup(argv[i]);
	if ((rc = decode_file(argv[i])) < 0) {
	    fprintf(stderr, "\tError decoding %s (%d)\n", argv[i], rc);
	    cnt++;
	}
	free(name);
    }

    if (debug) {
	fprintf(stderr,"encodes: %d\n", encode_counter);
	fprintf(stderr,"decodes: %d\n", decode_counter);
	fprintf(stderr,"writes:  %d\n", write_counter);
    }
    exit(cnt);
}

/*
 * Local variables:
 * c-basic-offset: 4
 * End:
 */