source: MondoRescue/branches/3.3/mindi-busybox/coreutils/dos2unix.c@ 3621

/* 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 GPLv2 or later, see file LICENSE in this source tree.
*/

//usage:#define dos2unix_trivial_usage
//usage:       "[-ud] [FILE]"
//usage:#define dos2unix_full_usage "\n\n"
//usage:       "Convert FILE in-place from DOS to Unix format.\n"
//usage:       "When no file is given, use stdin/stdout.\n"
//usage:     "\n    -u  dos2unix"
//usage:     "\n    -d  unix2dos"
//usage:
//usage:#define unix2dos_trivial_usage
//usage:       "[-ud] [FILE]"
//usage:#define unix2dos_full_usage "\n\n"
//usage:       "Convert FILE in-place from Unix to DOS format.\n"
//usage:       "When no file is given, use stdin/stdout.\n"
//usage:     "\n    -u  dos2unix"
//usage:     "\n    -d  unix2dos"

#include "libbb.h"

/* This is a NOEXEC applet. Be very careful! */

enum {
    CT_UNIX2DOS = 1,
    CT_DOS2UNIX
};

/* if fn is NULL then input is stdin and output is stdout */
static void convert(char *fn, int conv_type)
{
    FILE *in, *out;
    int ch;
    char *temp_fn = temp_fn; /* for compiler */
    char *resolved_fn = resolved_fn;

    in = stdin;
    out = stdout;
    if (fn != NULL) {
        struct stat st;
        int fd;

        resolved_fn = xmalloc_follow_symlinks(fn);
        if (resolved_fn == NULL)
            bb_simple_perror_msg_and_die(fn);
        in = xfopen_for_read(resolved_fn);
        xfstat(fileno(in), &st, resolved_fn);

        temp_fn = xasprintf("%sXXXXXX", resolved_fn);
        fd = xmkstemp(temp_fn);
        if (fchmod(fd, st.st_mode) == -1)
            bb_simple_perror_msg_and_die(temp_fn);
        fchown(fd, st.st_uid, st.st_gid);

        out = xfdopen_for_write(fd);
    }

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

    if (fn != NULL) {
        if (fclose(in) < 0 || fclose(out) < 0) {
            unlink(temp_fn);
            bb_perror_nomsg_and_die();
        }
        xrename(temp_fn, resolved_fn);
        free(temp_fn);
        free(resolved_fn);
    }
}

int dos2unix_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int dos2unix_main(int argc UNUSED_PARAM, char **argv)
{
    int o, conv_type;

    /* See if we are supposed to be doing dos2unix or unix2dos */
    conv_type = CT_UNIX2DOS;
    if (applet_name[0] == 'd') {
        conv_type = CT_DOS2UNIX;
    }

    /* -u convert to unix, -d convert to dos */
    opt_complementary = "u--d:d--u"; /* mutually exclusive */
    o = getopt32(argv, "du");

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

    argv += optind;
    do {
        /* might be convert(NULL) if there is no filename given */
        convert(*argv, conv_type);
    } while (*argv && *++argv);

    return 0;
}