source: MondoRescue/trunk/mindi-busybox/libbb/xgetularg.c@ 954

/* vi: set sw=4 ts=4: */
/*
 * xgetularg* implementations for busybox
 *
 * Copyright (C) 2003  Manuel Novoa III  <mjn3@codepoet.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 */

#include <stdlib.h>
#include <string.h>
#include <limits.h>
#include <ctype.h>
#include <errno.h>
#include <assert.h>
#include "libbb.h"

#ifdef L_xgetularg_bnd_sfx
unsigned long bb_xgetularg_bnd_sfx(const char *arg, int base,
                                   unsigned long lower,
                                   unsigned long upper,
                                   const struct suffix_mult *suffixes)
{
    unsigned long r;
    int old_errno;
    char *e;

    assert(arg);

    /* Disallow '-' and any leading whitespace.  Speed isn't critical here
     * since we're parsing commandline args.  So make sure we get the
     * actual isspace function rather than a larger macro implementaion. */
    if ((*arg == '-') || (isspace)(*arg)) {
        bb_show_usage();
    }

    /* Since this is a lib function, we're not allowed to reset errno to 0.
     * Doing so could break an app that is deferring checking of errno.
     * So, save the old value so that we can restore it if successful. */
    old_errno = errno;
    errno = 0;
    r = strtoul(arg, &e, base);
    /* Do the initial validity check.  Note: The standards do not
     * guarantee that errno is set if no digits were found.  So we
     * must test for this explicitly. */
    if (errno || (arg == e)) {  /* error or no digits */
        bb_show_usage();
    }
    errno = old_errno;  /* Ok.  So restore errno. */

    /* Do optional suffix parsing.  Allow 'empty' suffix tables.
     * Note that we also all nul suffixes with associated multipliers,
     * to allow for scaling of the arg by some default multiplier. */

    if (suffixes) {
        while (suffixes->suffix) {
            if (strcmp(suffixes->suffix, e) == 0) {
                if (ULONG_MAX / suffixes->mult < r) {   /* Overflow! */
                    bb_show_usage();
                }
                ++e;
                r *= suffixes->mult;
                break;
            }
            ++suffixes;
        }
    }

    /* Finally, check for illegal trailing chars and range limits. */
    /* Note: although we allow leading space (via stroul), trailing space
     * is an error.  It would be easy enough to allow though if desired. */
    if (*e || (r < lower) || (r > upper)) {
        bb_show_usage();
    }

    return r;
}
#endif

#ifdef L_xgetlarg_bnd_sfx
long bb_xgetlarg_bnd_sfx(const char *arg, int base,
                         long lower,
                         long upper,
                         const struct suffix_mult *suffixes)
{
    unsigned long u = LONG_MAX;
    long r;
    const char *p = arg;

    if ((*p == '-') && (p[1] != '+')) {
        ++p;
#if LONG_MAX == (-(LONG_MIN + 1))
        ++u;    /* two's complement */
#endif
    }

    r = bb_xgetularg_bnd_sfx(p, base, 0, u, suffixes);

    if (*arg == '-') {
        r = -r;
    }

    if ((r < lower) || (r > upper)) {
        bb_show_usage();
    }

    return r;
}
#endif

#ifdef L_getlarg10_sfx
long bb_xgetlarg10_sfx(const char *arg, const struct suffix_mult *suffixes)
{
    return bb_xgetlarg_bnd_sfx(arg, 10, LONG_MIN, LONG_MAX, suffixes);
}
#endif

#ifdef L_xgetularg_bnd
unsigned long bb_xgetularg_bnd(const char *arg, int base,
                               unsigned long lower,
                               unsigned long upper)
{
    return bb_xgetularg_bnd_sfx(arg, base, lower, upper, NULL);
}
#endif

#ifdef L_xgetularg10_bnd
unsigned long bb_xgetularg10_bnd(const char *arg,
                                 unsigned long lower,
                                 unsigned long upper)
{
    return bb_xgetularg_bnd(arg, 10, lower, upper);
}
#endif

#ifdef L_xgetularg10
unsigned long bb_xgetularg10(const char *arg)
{
    return bb_xgetularg10_bnd(arg, 0, ULONG_MAX);
}
#endif