src/ucx.c

/**
 * @mainpage UAP Common Extensions
 * Library with common and useful functions, macros and data structures.
 * <p>
 * Latest available source:<br>
 * <a href="https://sourceforge.net/projects/ucx/files/">
 * https://sourceforge.net/projects/ucx/files/</a>
 * </p>
 * 
 * <p>
 * Repositories:<br>
 * <a href="https://sourceforge.net/p/ucx/code">
 * https://sourceforge.net/p/ucx/code</a>
 * -&nbsp;or&nbsp;-
 * <a href="https://develop.uap-core.de/hg/ucx">
 * https://develop.uap-core.de/hg/ucx</a>
 * </p>
 * 
 * <h2>LICENCE</h2>
 * 
 * Copyright 2017 Mike Becker, Olaf Wintermann All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *
 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "ucx/ucx.h"

#ifndef UCX_MUL_BUILTIN
int ucx_szmul(size_t a, size_t b, size_t *result) {
    if(a == 0 || b == 0) {
        *result = 0;
        return 0;
    }
    size_t r = a * b;
    if(r / b == a) {
        *result = r;
        return 0;
    } else {
        *result = 0;
        return 1;
    }
}
#endif