source: MondoRescue/trunk/mindi-busybox/coreutils/dos2unix.c@ 929

/* vi: set sw=4 ts=4: */
/*
 * dos2unix for BusyBox
 *
 * dos2unix '\n' convertor 0.5.0
 * based on Unix2Dos 0.9.0 by Peter Hanecak (made 19.2.1997)
 * Copyright 1997,.. by Peter Hanecak <hanecak@megaloman.sk>.
 * All rights reserved.
 *
 * dos2unix filters reading input from stdin and writing output to stdout.
 *
 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
*/

#include <string.h>
#include <unistd.h>
#include <stdint.h>
#include <fcntl.h>
#include "busybox.h"

enum ConvType {
    CT_UNIX2DOS = 1,
    CT_DOS2UNIX
} ConvType;

/* if fn is NULL then input is stdin and output is stdout */
static int convert(char *fn)
{
    FILE *in, *out;
    int i;

    if (fn != NULL) {
        in = bb_xfopen(fn, "rw");
        /*
           The file is then created with mode read/write and
           permissions 0666 for glibc 2.0.6 and earlier or
           0600  for glibc  2.0.7 and  later.
         */
        snprintf(bb_common_bufsiz1, sizeof(bb_common_bufsiz1), "%sXXXXXX", fn);
        /*
           sizeof bb_common_bufsiz1 is 4096, so it should be big enough to
           hold the full path.  However if the output is truncated the
           subsequent call to mkstemp would fail.
         */
        if ((i = mkstemp(&bb_common_bufsiz1[0])) == -1
            || chmod(bb_common_bufsiz1, 0600) == -1) {
            bb_perror_nomsg_and_die();
        }
        out = fdopen(i, "w+");
        if (!out) {
            close(i);
            remove(bb_common_bufsiz1);
        }
    } else {
        in = stdin;
        out = stdout;
    }

    while ((i = fgetc(in)) != EOF) {
        if (i == '\r')
            continue;
        if (i == '\n') {
            if (ConvType == CT_UNIX2DOS)
                fputc('\r', out);
            fputc('\n', out);
            continue;
        }
        fputc(i, out);
    }

    if (fn != NULL) {
        if (fclose(in) < 0 || fclose(out) < 0) {
            bb_perror_nomsg();
            remove(bb_common_bufsiz1);
            return -2;
        }
        /* Assume they are both on the same filesystem (which
         * should be true since we put them into the same directory
         * so we _should_ be ok, but you never know... */
        if (rename(bb_common_bufsiz1, fn) < 0) {
            bb_perror_msg("cannot rename '%s' as '%s'", bb_common_bufsiz1, fn);
            return -1;
        }
    }

    return 0;
}

int dos2unix_main(int argc, char *argv[])
{
    int o;

    /* See if we are supposed to be doing dos2unix or unix2dos */
    if (bb_applet_name[0] == 'd') {
        ConvType = CT_DOS2UNIX; /*2 */
    } else {
        ConvType = CT_UNIX2DOS; /*1 */
    }
    /* -u and -d are mutally exclusive */
    bb_opt_complementally = "?:u--d:d--u";
    /* process parameters */
    /* -u convert to unix */
    /* -d convert to dos  */
    o = bb_getopt_ulflags(argc, argv, "du");

    /* Do the conversion requested by an argument else do the default
     * conversion depending on our name.  */
    if (o)
        ConvType = o;

    if (optind < argc) {
        while (optind < argc)
            if ((o = convert(argv[optind++])) < 0)
                break;
    } else
        o = convert(NULL);

    return o;
}