source: MondoRescue/branches/3.3/mindi-busybox/coreutils/catv.c@ 3865

/* 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 source tree.
 */

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

//usage:#define catv_trivial_usage
//usage:       "[-etv] [FILE]..."
//usage:#define catv_full_usage "\n\n"
//usage:       "Display nonprinting characters as ^x or M-x\n"
//usage:     "\n    -e  End each line with $"
//usage:     "\n    -t  Show tabs as ^I"
//usage:     "\n    -v  Don't use ^x or M-x escapes"

#include "libbb.h"
#include "common_bufsiz.h"

#define CATV_OPT_e (1<<0)
#define CATV_OPT_t (1<<1)
#define CATV_OPT_v (1<<2)
struct BUG_const_mismatch {
    char BUG_const_mismatch[
        CATV_OPT_e == VISIBLE_ENDLINE && CATV_OPT_t == VISIBLE_SHOW_TABS
        ? 1 : -1
    ];
};

int catv_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int catv_main(int argc UNUSED_PARAM, char **argv)
{
    int retval = EXIT_SUCCESS;
    int fd;
    unsigned opts;
    opts = getopt32(argv, "etv");
    argv += optind;
#if 0 /* These consts match, we can just pass "opts" to visible() */
    if (opts & CATV_OPT_e)
        flags |= VISIBLE_ENDLINE;
    if (opts & CATV_OPT_t)
        flags |= VISIBLE_SHOW_TABS;
#endif

    /* Read from stdin if there's nothing else to do. */
    if (!argv[0])
        *--argv = (char*)"-";

#define read_buf bb_common_bufsiz1
    setup_common_bufsiz();
    do {
        fd = open_or_warn_stdin(*argv);
        if (fd < 0) {
            retval = EXIT_FAILURE;
            continue;
        }
        for (;;) {
            int i, res;

            res = read(fd, read_buf, COMMON_BUFSIZE);
            if (res < 0)
                retval = EXIT_FAILURE;
            if (res <= 0)
                break;
            for (i = 0; i < res; i++) {
                unsigned char c = read_buf[i];
                if (opts & CATV_OPT_v) {
                    putchar(c);
                } else {
                    char buf[sizeof("M-^c")];
                    visible(c, buf, opts);
                    fputs(buf, stdout);
                }
            }
        }
        if (ENABLE_FEATURE_CLEAN_UP && fd)
            close(fd);
    } while (*++argv);

    fflush_stdout_and_exit(retval);
}