root/usr.bin/fortune/unstr/unstr.c
/*-
 * Copyright (c) 1991, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Ken Arnold.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 *      This program un-does what "strfile" makes, thereby obtaining the
 * original file again.  This can be invoked with the name of the output
 * file, the input file, or both. If invoked with only a single argument
 * ending in ".dat", it is pressumed to be the input file and the output
 * file will be the same stripped of the ".dat".  If the single argument
 * doesn't end in ".dat", then it is presumed to be the output file, and
 * the input file is that name prepended by a ".dat".  If both are given
 * they are treated literally as the input and output files.
 *
 *      Ken Arnold              Aug 13, 1978
 */

#include <sys/param.h>
#include <sys/endian.h>
#include <ctype.h>
#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "strfile.h"

static char     *Infile,                /* name of input file */
                Datafile[MAXPATHLEN],   /* name of data file */
                Delimch;                /* delimiter character */

static FILE     *Inf, *Dataf;

static void order_unstr(STRFILE *);

/* ARGSUSED */
int
main(int argc, char *argv[])
{
        static STRFILE tbl;             /* description table */

        if (argc != 2) {
                fprintf(stderr, "usage: unstr datafile\n");
                exit(1);
        }
        Infile = argv[1];
        if ((size_t)snprintf(Datafile, sizeof(Datafile), "%s.dat", Infile) >=
            sizeof(Datafile)) 
                errx(1, "%s name too long", Infile);
        if ((Inf = fopen(Infile, "r")) == NULL)
                err(1, "%s", Infile);
        if ((Dataf = fopen(Datafile, "r")) == NULL)
                err(1, "%s", Datafile);
        if (fread((char *)&tbl, sizeof(tbl), 1, Dataf) != 1) {
                if (feof(Dataf))
                        errx(1, "%s read EOF", Datafile);
                else
                        err(1, "%s read", Datafile);
        }
        tbl.str_version = be32toh(tbl.str_version);
        tbl.str_numstr = be32toh(tbl.str_numstr);
        tbl.str_longlen = be32toh(tbl.str_longlen);
        tbl.str_shortlen = be32toh(tbl.str_shortlen);
        tbl.str_flags = be32toh(tbl.str_flags);
        if (!(tbl.str_flags & (STR_ORDERED | STR_RANDOM)))
                errx(1, "nothing to do -- table in file order");
        Delimch = tbl.str_delim;
        order_unstr(&tbl);
        fclose(Inf);
        fclose(Dataf);
        exit(0);
}

static void
order_unstr(STRFILE *tbl)
{
        uint32_t i;
        char *sp;
        off_t pos;
        char buf[BUFSIZ];

        for (i = 0; i < tbl->str_numstr; i++) {
                fread(&pos, 1, sizeof(pos), Dataf);
                fseeko(Inf, be64toh(pos), SEEK_SET);
                if (i != 0)
                        printf("%c\n", Delimch);
                for (;;) {
                        sp = fgets(buf, sizeof(buf), Inf);
                        if (sp == NULL || STR_ENDSTRING(sp, *tbl))
                                break;
                        else
                                fputs(sp, stdout);
                }
        }
}