~drizzle-trunk/drizzle/development

/* Copyright (C) 2003 MySQL AB

   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; version 2 of the License.

   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 <mystrings/m_string.h>  /* strchr() */

#include <mystrings/m_ctype.h>  /* my_isspace() */

#include <mysys/base64.h>

#ifndef MAIN

static char base64_table[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

                             "abcdefghijklmnopqrstuvwxyz"

                             "0123456789+/";

int

base64_needed_encoded_length(int length_of_data)

{

  int nb_base64_chars;

  nb_base64_chars= (length_of_data + 2) / 3 * 4;

  return

    nb_base64_chars +            /* base64 char incl padding */

    (nb_base64_chars - 1)/ 76 +  /* newlines */

    1;                           /* NUL termination of string */

}

int

base64_needed_decoded_length(int length_of_encoded_data)

{

  return (int) ceil(length_of_encoded_data * 3 / 4);

}

/*

  Encode a data as base64.

  Note: We require that dst is pre-allocated to correct size.

        See base64_needed_encoded_length().

*/

int

base64_encode(const void *src, size_t src_len, char *dst)

{

  const unsigned char *s= (const unsigned char*)src;

  size_t i= 0;

  size_t len= 0;

  for (; i < src_len; len += 4)

  {

    unsigned c;

    if (len == 76)

    {

      len= 0;

      *dst++= '\n';

    }

    c= s[i++];

    c <<= 8;

    if (i < src_len)

      c += s[i];

    c <<= 8;

    i++;

    if (i < src_len)

      c += s[i];

    i++;

    *dst++= base64_table[(c >> 18) & 0x3f];

    *dst++= base64_table[(c >> 12) & 0x3f];

    if (i > (src_len + 1))

      *dst++= '=';

    else

      *dst++= base64_table[(c >> 6) & 0x3f];

    if (i > src_len)

      *dst++= '=';

    else

      *dst++= base64_table[(c >> 0) & 0x3f];

  }

  *dst= '\0';

  return 0;

}

static inline uint

pos(unsigned char c)

{

  return (uint) (strchr(base64_table, c) - base64_table);

}

#define SKIP_SPACE(src, i, size)                                \

{                                                               \

  while (i < size && my_isspace(&my_charset_latin1, * src))     \

  {                                                             \

    i++;                                                        \

    src++;                                                      \

  }                                                             \

  if (i == size)                                                \

  {                                                             \

    break;                                                      \

  }                                                             \

}

/*

  Decode a base64 string

  SYNOPSIS

    base64_decode()

    src      Pointer to base64-encoded string

    len      Length of string at 'src'

    dst      Pointer to location where decoded data will be stored

    end_ptr  Pointer to variable that will refer to the character

             after the end of the encoded data that were decoded. Can

             be NULL.

  DESCRIPTION

    The base64-encoded data in the range ['src','*end_ptr') will be

    decoded and stored starting at 'dst'.  The decoding will stop

    after 'len' characters have been read from 'src', or when padding

    occurs in the base64-encoded data. In either case: if 'end_ptr' is

    non-null, '*end_ptr' will be set to point to the character after

    the last read character, even in the presence of error.

  NOTE

    We require that 'dst' is pre-allocated to correct size.

  SEE ALSO

    base64_needed_decoded_length().

  RETURN VALUE

    Number of bytes written at 'dst' or -1 in case of failure

*/

int

base64_decode(const char *src_base, size_t len,

              void *dst, const char **end_ptr)

{

  char b[3];

  size_t i= 0;

  char *dst_base= (char *)dst;

  char const *src= src_base;

  char *d= dst_base;

  size_t j;

  while (i < len)

  {

    unsigned c= 0;

    size_t mark= 0;

    SKIP_SPACE(src, i, len);

    c += pos(*src++);

    c <<= 6;

    i++;

    SKIP_SPACE(src, i, len);

    c += pos(*src++);

    c <<= 6;

    i++;

    SKIP_SPACE(src, i, len);

    if (*src != '=')

      c += pos(*src++);

    else

    {

      src += 2;                /* There should be two bytes padding */

      i= len;

      mark= 2;

      c <<= 6;

      goto end;

    }

    c <<= 6;

    i++;

    SKIP_SPACE(src, i, len);

    if (*src != '=')

      c += pos(*src++);

    else

    {

      src += 1;                 /* There should be one byte padding */

      i= len;

      mark= 1;

      goto end;

    }

    i++;

  end:

    b[0]= (c >> 16) & 0xff;

    b[1]= (c >>  8) & 0xff;

    b[2]= (c >>  0) & 0xff;

    for (j=0; j<3-mark; j++)

      *d++= b[j];

  }

  if (end_ptr != NULL)

    *end_ptr= src;

  /*

    The variable 'i' is set to 'len' when padding has been read, so it

    does not actually reflect the number of bytes read from 'src'.

   */

  return i != len ? -1 : d - dst_base;

}

#else /* MAIN */

#define require(b) { \

  if (!(b)) { \

    printf("Require failed at %s:%d\n", __FILE__, __LINE__); \

    abort(); \

  } \

}

int

main(void)

{

  int i;

  size_t j;

  size_t k, l;

  size_t dst_len;

  size_t needed_length;

  for (i= 0; i < 500; i++)

  {

    /* Create source data */

    const size_t src_len= rand() % 1000 + 1;

    char * src= (char *) malloc(src_len);

    char * s= src;

    char * str;

    char * dst;

    require(src);

    for (j= 0; j<src_len; j++)

    {

      char c= rand();

      *s++= c;

    }

    /* Encode */

    needed_length= base64_needed_encoded_length(src_len);

    str= (char *) malloc(needed_length);

    require(str);

    for (k= 0; k < needed_length; k++)

      str[k]= 0xff; /* Fill memory to check correct NUL termination */

    require(base64_encode(src, src_len, str) == 0);

    require(needed_length == strlen(str) + 1);

    /* Decode */

    dst= (char *) malloc(base64_needed_decoded_length(strlen(str)));

    require(dst);

    dst_len= base64_decode(str, strlen(str), dst, NULL);

    require(dst_len == src_len);

    if (memcmp(src, dst, src_len) != 0)

    {

      printf("       --------- src ---------   --------- dst ---------\n");

      for (k= 0; k<src_len; k+=8)

      {

        printf("%.4x   ", (uint) k);

        for (l=0; l<8 && k+l<src_len; l++)

        {

          unsigned char c= src[k+l];

          printf("%.2x ", (unsigned)c);

        }

        printf("  ");

        for (l=0; l<8 && k+l<dst_len; l++)

        {

          unsigned char c= dst[k+l];

          printf("%.2x ", (unsigned)c);

        }

        printf("\n");

      }

      printf("src length: %.8x, dst length: %.8x\n",

             (uint) src_len, (uint) dst_len);

      require(0);

    }

  }

  printf("Test succeeded.\n");

  return 0;

}

#endif