libs/luanet/src/base64.c

   1 /*
   2  * Base64.c
   3  * Copyright (c) 2006 Ryan Martell. (rdm4@martellventures.com)
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <unistd.h>
  26
  27 #include <lua.h>
  28 #include <lualib.h>
  29 #include <lauxlib.h>
  30
  31
  32 unsigned char map2[] =
  33 {
  34     0x3e, 0xff, 0xff, 0xff, 0x3f, 0x34, 0x35, 0x36,
  35     0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0xff,
  36     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x01,
  37     0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,
  38     0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11,
  39     0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19,
  40     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x1a, 0x1b,
  41     0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21, 0x22, 0x23,
  42     0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b,
  43     0x2c, 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33
  44 };
  45
  46 int b64_decode(lua_State *L)
  47 {
  48     int i, v;
  49         unsigned char out[512];
  50         unsigned char *dst = out;
  51         char *in;
  52         if(lua_gettop(L) != 1)
  53         {
  54                 lua_pushstring(L, "invalid arg list");
  55                 lua_error(L);
  56                 return 0;
  57         }
  58         in = (char *)lua_tostring (L, 1);
  59     v = 0;
  60     for (i = 0; in[i] && in[i] != '='; i++) {
  61         unsigned int index= in[i]-43;
  62         if (index>=(sizeof(map2)/sizeof(map2[0])) || map2[index] == 0xff)
  63             return -1;
  64         v = (v << 6) + map2[index];
  65         if (i & 3) {
  66             if (dst - out < 512) {
  67                 *dst++ = v >> (6 - 2 * (i & 3));
  68             }
  69         }
  70     }
  71         if(!(dst - out))
  72                 return 0;
  73          lua_pushstring(L, (char*)out);
  74     return 1;
  75 }
  76
  77 /*****************************************************************************
  78 * b64_encode: stolen from VLC's http.c
  79 * simplified by michael
  80 * fixed edge cases and made it work from data (vs. strings) by ryan.
  81 *****************************************************************************/
  82
  83 int b64_encode(lua_State *L)
  84 {
  85     static const char b64[] =
  86         "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
  87     char *ret, *dst, *src, tmp[1024];
  88     unsigned i_bits = 0;
  89     int i_shift = 0;
  90     int bytes_remaining, len;
  91         if(lua_gettop(L) != 1)
  92         {
  93                 lua_pushstring(L, "invalid arg list");
  94                 lua_error(L);
  95                 return 0;
  96         }
  97         src = (char *)lua_tostring (L, 1);
  98     bytes_remaining = len = strlen(src);
  99         if (len < 512) {
 100         ret = dst = tmp;
 101     } else
 102         return 0;
 103
 104     if (len) {                  // special edge case, what should we really do here?
 105         while (bytes_remaining) {
 106             i_bits = (i_bits << 8) + *src++;
 107             bytes_remaining--;
 108             i_shift += 8;
 109
 110             do {
 111                 *dst++ = b64[(i_bits << 6 >> i_shift) & 0x3f];
 112                 i_shift -= 6;
 113             } while (i_shift > 6 || (bytes_remaining == 0 && i_shift > 0));
 114         }
 115         while ((dst - ret) & 3)
 116             *dst++ = '=';
 117     }
 118     *dst = '\0';
 119         lua_pushstring(L, tmp);
 120     return 1;
 121 }