source: MondoRescue/trunk/mindi-busybox/coreutils/catv.c@ 863

/* vi: set sw=4 ts=4: */
/*
 * cat -v implementation for busybox
 *
 * Copyright (C) 2006 Rob Landley <rob@landley.net>
 *
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 */

/* See "Cat -v considered harmful" at
 * http://cm.bell-labs.com/cm/cs/doc/84/kp.ps.gz */

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

int catv_main(int argc, char **argv)
{
    int retval = EXIT_SUCCESS, fd, flags;

    flags = bb_getopt_ulflags(argc, argv, "etv");
    flags ^= 4;

    // Loop through files.

    argv += optind;
    do {
        // Read from stdin if there's nothing else to do.

        fd = 0;
        if (*argv && 0>(fd = bb_xopen(*argv, O_RDONLY))) retval = EXIT_FAILURE;
        else for(;;) {
            int i, res;

            res = read(fd, bb_common_bufsiz1, sizeof(bb_common_bufsiz1));
            if (res < 0) retval = EXIT_FAILURE;
            if (res <1) break;
            for (i=0; i<res; i++) {
                char c=bb_common_bufsiz1[i];

                if (c > 126 && (flags & 4)) {
                    if (c == 127) {
                        printf("^?");
                        continue;
                    } else {
                        printf("M-");
                        c -= 128;
                    }
                }
                if (c < 32) {
                    if (c == 10) {
                       if (flags & 1) putchar('$');
                    } else if (flags & (c==9 ? 2 : 4)) {
                        printf("^%c", c+'@');
                        continue;
                    }
                }
                putchar(c);
            }
        }
        if (ENABLE_FEATURE_CLEAN_UP && fd) close(fd);
    } while (*++argv);

    return retval;
}