/* mdXhl.c

 * ----------------------------------------------------------------------------

 * "THE BEER-WARE LICENSE" (Revision 42):

 * <phk@freebsd.org> wrote this file.  As long as you retain this notice you</phk@freebsd.org>

 * can do whatever you want with this stuff. If we meet some day, and you think

 * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp

 * ----------------------------------------------------------------------------

 * libjpeg-turbo Modifications:

 * Copyright (C)2016, 2018-2019 D. R. Commander.  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 the libjpeg-turbo 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 HOLDERS 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 <sys types.h=""></sys>

#include <sys stat.h=""></sys>

#include <fcntl.h></fcntl.h>

#ifdef _WIN32

#include <io.h></io.h>

#define close  _close

#define fstat  _fstat

#define lseek  _lseek

#define read  _read

#define stat  _stat

#else

#include <unistd.h></unistd.h>

#endif

#include <errno.h></errno.h>

#include <stdio.h></stdio.h>

#include <stdlib.h></stdlib.h>

#define LENGTH  16

#include "./md5.h"

static char *MD5End(MD5_CTX *ctx, char *buf)

{

  int i;

  unsigned char digest[LENGTH];

  static const char hex[] = "0123456789abcdef";

  if (!buf)

    buf = malloc(2 * LENGTH + 1);

  if (!buf)

    return 0;

  MD5Final(digest, ctx);

  for (i = 0; i < LENGTH; i++) {

    buf[i + i] = hex[digest[i] >> 4];

    buf[i + i + 1] = hex[digest[i] & 0x0f];

  }

  buf[i + i] = '\0';

  return buf;

}

char *MD5File(const char *filename, char *buf)

{

  return (MD5FileChunk(filename, buf, 0, 0));

}

char *MD5FileChunk(const char *filename, char *buf, off_t ofs, off_t len)

{

  unsigned char buffer[BUFSIZ];

  MD5_CTX ctx;

  struct stat stbuf;

  int f, i, e;

  off_t n;

  MD5Init(&ctx);

#ifdef _WIN32

  f = _open(filename, O_RDONLY | O_BINARY);

#else

  f = open(filename, O_RDONLY);

#endif

  if (f < 0)

    return 0;

  if (fstat(f, &stbuf) < 0)

    return 0;

  if (ofs > stbuf.st_size)

    ofs = stbuf.st_size;

  if ((len == 0) || (len > stbuf.st_size - ofs))

    len = stbuf.st_size - ofs;

  if (lseek(f, ofs, SEEK_SET) < 0)

    return 0;

  n = len;

  i = 0;

  while (n > 0) {

    if (n > sizeof(buffer))

      i = read(f, buffer, sizeof(buffer));

    else

      i = read(f, buffer, n);

    if (i < 0)

      break;

    MD5Update(&ctx, buffer, i);

    n -= i;

  }

  e = errno;

  close(f);

  errno = e;

  if (i < 0)

    return 0;

  return (MD5End(&ctx, buf));

}