slice.h

/* Copyright (c) 2016, Robert Escriva
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *     * Redistributions of source code must retain the above copyright notice,
 *       this list of conditions and the following disclaimer.
 *     * 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.
 *     * Neither the name of this project nor the names of its contributors may
 *       be used to endorse or promote products derived from this software
 *       without specific prior written permission.
 *
 * 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 OWNER 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.
 */

#ifndef macaroons_slice_h_
#define macaroons_slice_h_

/* c */
#include <stddef.h>

#define EMPTY_SLICE {NULL, 0};

struct slice
{
    const unsigned char* data;
    size_t size;
};

/* copy data_sz bytes from data to ptr, and set sl to point to the copied bytes;
 * return a pointer to the first unused byte after the slice
 */
unsigned char*
copy_to_slice(const unsigned char* data, size_t data_sz,
              struct slice* sl, unsigned char* ptr);
/* unpack a slice into its parts, result points to same memory
 */
void
unstruct_slice(const struct slice* sl, const unsigned char** data, size_t* data_sz);
/* copy slice from to ptr, and set to to point to the copied bytes; return a
 * pointer to the first unused byte after to
 */
unsigned char*
copy_slice(const struct slice* from,
           struct slice* to,
           unsigned char* ptr);
/* 0 if equal; !0 if non-equal; no other comparison implied */
int
slice_cmp(const struct slice* lhs,
          const struct slice* rhs);

#endif /* macaroons_slice_h_ */